International Nuclear Information System (INIS)

Naturally occurring radioactive materials (NORM) in seven new type wall materials were surveyed. The radioactivity was determined with HPGe-#gamma# spectrometer. The red mud has the highest radioactivity concentration, followed by slag building blocks, fly-ash building blocks (bricks), gangue bricks and light weight board materials, gypsum blocks. Fly-ash and slag contain higher NORM, which contributes the major part of the radioactivity in new wall materials. (authors)

International Nuclear Information System (INIS)

A few industry-derived and conventional building materials have above acceptable radioactivity. An examination of some materials presently used, or with a potential for use, has shown that in phosphogypsum, fly ash, zircon kyanite tailings, red mud and brickmaking clay, the radium equivalent activities of the finer fractions (<53 #mu#) are higher than those of the larger fractions. Consequently, the radioactivity of these materials could be reduced by dry-sieving and discarding the fines. In blast furnace slag and dissociated zircon, no such reduction would occur since the radioactivity is evenly distributed in all sized fractions.

International Nuclear Information System (INIS)

Oil and gas production and processing operations sometimes cause naturally occurring radioactive materials (NORM) to accumulate at elevated concentrations in by-product waste streams. The sources of most of the radioactivity are isotopes of "2"3"8U and "2"3"2Th series, which are naturally present in the subsurface formations from which oil and gas are produced. NORM waste may cause problems in the operations of installations by plugging perforations, clogging tubular and valves then restricting flow. Therefore, plants or equipment have to be refurbished and decontaminated before reuse to avoid radioactive waste or surface contaminated object. There are two options for safe disposal of scale and sludge produced from NORM Descaling Facility : 1- Injection into an abandoned production well. 2- The construction of a near surface depository. These options are assumed to be environmental ...

Energy Technology Data Exchange (ETDEWEB)

The Department of Toxic Substance Control (DTSC) requested that Lawrence Livermore National Laboratory (LLNL) evaluate the treatment process currently employed at the Department's Stringfellow Superfund Site Pretreatment Plant (PTP) site to determine if wastes originating from the site were properly managed with regards to their radioactivity. In order to evaluate the current management strategy, LLNL suggested that DTSC characterize the effluents from the waste treatment system for radionuclide content. A sampling plan was developed; samples were collected and analyzed for radioactive constituents. Following is brief summary of those results and what implications for waste characterization may be made. (1) The sampling and analysis provides strong evidence that the radionuclides present are Naturally Occurring Radioactive Material (NORM). (2) The greatest source of ...

Energy Technology Data Exchange (ETDEWEB)

The Environmental Protection Agency (EPA) is developing generally applicable environmental standards for land disposal of Atomic Energy Act (AEA) low-level radioactive wastes (LLW) and certain naturally occurring and accelerator-produced radioactive material (NARM) wastes. It is EPA's intention that the LLW standards will protect public health and the environment. The LLW standards would cover disposal of all AEA materials not controlled by other EPA standards and some natural radioactive materials. Coverage of federal waste is significant, because the federal government generates and disposes of >40% of all LLW nationwide, and a uniform standard for all LLW disposal is both a desirable and an achievable goal. Publication of a proposed LLW standard is planned in 1988, and a final standard a year later. This standard will have ...

International Nuclear Information System (INIS)

Processing certain raw materials containing natural radioactive isotopes (e.g. U-238, Th-232 or K- 40) into products such as glas, abrasives, grinding materials or electrodes used for gasshielded tungsten-arc welding also leads to certain concentrations of industrial waste containing natural radioactive materials. Such industrial waste does not necessarily contain natural radioactive substances in concentrations exceeding the highest possible levels but nevertheless in significantly measurable quantities. This, however, frequently leads to confusion bordering on irritation by entities processing such substances as well as the general public, since they tend to believe natural radioactive substances in unobjectable concentration to cause similar or identical - health - consequences as man made radioactive substances in ...

International Nuclear Information System (INIS)

... NUCLEAR FUEL CYCLE AND FUEL MATERIALS borophosphate glass

Energy Technology Data Exchange (ETDEWEB)

In the corrosion aspect of container for the deep geological disposal of high-level radioactive waste, disposal concepts and the related container materials, which have been developed by advanced countries, have been reviewed. The disposal circumstances could be divided into the saturated and the unsaturated zones. The candidate materials in the countries, which consider the disposal in the unsaturated zone, are the corrosion resistant materials such as supper alloys and stainless steels, but those in the saturated zone is cupper, one of the corrosion allowable materials. By the results of the pitting corrosion test of sensitized stainless steels (such as 304, 304L, 316 and 316L), pitting potential is decreased with the degree of sensitization and the pitting corrosion resistance of 316L is higher than others. And so, the long-term corrosion experiment with 316L stainless steel ...

International Nuclear Information System (INIS)

Naturally occurring radionuclides are present in most material. The most common naturally occurring radionuclides in material are those of the uranium and thorium series and potassium-40. This material is commonly referred to as Naturally Occurring Radioactive Material (NORM). In some material the levels of naturally occurring radionuclides are significantly higher, to the extent that regulatory control may be required for radiation protection purposes. Regulation of NORM presents a range of new challenges for both regulators and operators. Unlike more traditional industries dealing with radionuclides, NORM industries have generally not had any radiological oversight and, for example, are not equipped for radiological monitoring. Some consumer goods containing NORM, which have ...

International Nuclear Information System (INIS)

Up to now the retention of radioactive material for nuclear facilities has been based on the maximum individual dose. The maximum individual dose can locally be lowered considerably by higher dissolution. In general, the collective doses are not lowered by this. In order to set up regulations concerning collective doses, the new recommmendations of the ICRP are very welcome. However, the costs of detriment and the period to be considered have not yet been defined. Therefore there are no fixed methods for carrying out a cost-benefit analysis. Furthermore, for nuclear technology the costs and the effectiveness of the retention of radioactive material for non-realized facilities can only be quoted roughly, which makes a cost-benefit analysis more difficult. A cost-benefit analysis for the retention of radioactive material in nuclear power plants with LWRs and ...

International Nuclear Information System (INIS)

Lanthanum halide (LaBr_3:Ce) scintillators offer significantly better resolution (< 3% at 662 keV) relative to NaI(Tl) and have recently become commercially available in sizes large enough for the handheld, Radio-Isotope Identification Device (RIID) market. Drawbacks to lanthanum halide detectors, however, include internal radioactivity contributing to spectral counts, and a low-energy response which can cause detector resolution to be worse than that of NaI(Tl) below 100 keV. To study the potential of this new material for RIIDs we performed a series of measurements comparing a 1.5 x 1.5-inch LaBr_3:Ce detector with an Exploranium GR-135 RIID, which contains a 1.5 x 2.2-inch NaI(Tl) detector. Measurements were taken for short timeframes, as typifies RIID usage. Measurements included examples of naturally occurring radioactive material (NORM), typically found in cargo, and ...

Energy Technology Data Exchange (ETDEWEB)

An easy and simple method for gamma assay of large multi-gamma lines samples was introduced in this work. This method performs the assay using point source calibration. The correction factors for volume and self-attenuation are experimentally deduced from the spectra of different thicknesses samples utilizing the following two simple well known facts: large and small samples of the same homogenous material have identical specific activities; the self-attenuation of gamma line decreases as its energy increases. The method was successfully applied to naturally occurring radioactive material (NORM) large samples. This method does not require complicated mathematical procedures. Neither sample matrix data nor detector unit composition is needed.

International Nuclear Information System (INIS)

An easy and simple method for gamma assay of large multi gamma lines samples was introduced in this work. This method performs the assay using point source calibration. The correction factors for volume and self-attenuation are experimentally deduced from the spectra of different thicknesses samples utilizing the following tow simple well known facts: Large and small samples of the same homogenous material have identical activities; the self attenuation of gamma line decreases as its energy increases. The method was successfully applied to NORM (Naturally Occurring Radioactive Material) large samples. This method doesn't require complicated mathematical procedures. Neither sample matrix data nor detector unit composition is needed. (author)

Energy Technology Data Exchange (ETDEWEB)

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. This practice results in the commingling and disposal of clean and contaminated material as low-level waste (LLW), or possibly low-level mixed waste (LLMW). Until recently, volume reduction of radioactively contaminated soil depended on manual screening and analysis of samples, which is a costly and impractical approach and does not uphold As Low As Reasonably Achievable (ALARA) principles. To reduce the amount ...

International Nuclear Information System (INIS)

An IAEA databank lists a number of reported cases of illicitly trafficked nuclear or other radioactive materials. Apart from the traditional concern with nuclear proliferation, the post September 11th public is now wary of a possible attack by terrorists with a nuclear or radiation dispersion device (RDD). Until now, the seized quantities have not been sufficient to manufacture a nuclear explosive device, but they might be enough to construct an RDD. Recognizing the latent global challenge to public health and safety, the G8 States (Japan, USA, Germany, France, UK, Italy, Canada, and Russia) have called for 'joint international efforts to identify and suppress illicit supply' of, and demand for, nuclear material and to deter potential traffickers. One measure gaining in significance is to identify seized material and trace it back to its origin the objective of an emerging science known as nuclear ...

Energy Technology Data Exchange (ETDEWEB)

The present review focuses on the isotropic composition in extra-terrestrial materials. There are many different factors in the variation in isotopic abundance between terrestrial and extra-terrestrial materials. Major factors in unusual isotopic composition are roughly grouped into three categories: factors associated with fractionation of isotopes, nuclear reaction or radioactive disintegration. Fractionation takes place due to differences in mass among various isotopes. There are physical and chemical factors. Physical ones include vaporization and condensation which meteorites may experience during their formation while the chemical ones include chemical reactions and chemical equilibration. There phenomena are mentioned as factors in the variation in isotopic ratio which is associated with nuclear reactions. An important nuclear reaction is the formation of elements that has been occurring ...

Energy Technology Data Exchange (ETDEWEB)

A general criterion has been suggested for deep geological repositories containing spent fuel - the repositories should impose no greater radiological risk than due to naturally occurring uranium deposits. The following analysis investigates the rationale of that suggestion and determines whether current expectations of spent-fuel repository performance are consistent with such a criterion. In this study, reference spent-fuel repositories were compared to natural uranium-ore deposits. Comparisons were based on intrinsic characteristics, such as radionuclide inventory, depth, proximity to aquifers, and regional distribution, and actual and potential radiological consequences that are now occurring from some ore deposits and that may eventually occur from repositories and other ore deposits. The comparison results show that the repositories are quite comparable to the natural ore deposits and, in some cases, present less ...

International Nuclear Information System (INIS)

Full text: In Hungary, the main goal is that the Hungarian regulations should meet with the EU Directive No. 96/29. For this aim, a surveying project has been launched in order to collect all relevant information about the Hungarian TENORM situation. This surveying programme covers a lot of data collection (work activities, disposal places, residue quantities) and radiological measurements on the TENORM site. The Hungarian situation of TENORM definitely differs from other countries in the aspect of occurrence forms of natural sources (or in the imported raw materials), in the quantities of exploitation, in the level of the radioactivity and in the applied technological processes. Firstly, those work activities have been choosen where the huge amount of residues have been produced. The other criteria is that the activity concentration in a great portion of the given residues is much higher than the average activity concentration of the typical ...

Energy Technology Data Exchange (ETDEWEB)

Grout has been evaluated as a means of containing low-level radioactive waste for long-term disposal. Concerns about hydrogen and reactive gas generation in the Hanford Site grout disposal facility lead to the development of the G3 model, which has predicted buildup of radiolytically formed gases in the grout region and their migration to air-filled regions. The G3 model is a one-dimensional code that couples models of gas diffusion with two-phase gas and liquid flow. It was coupled to a compartment diffusion model and these models predicted the concentrations of hydrogen I nitrous oxide, and other gases in air-filled regions of the grout disposal facility. The results have served as the technical basis for safety studies. A unique finding of the G3 model was that a liquid return, or expulsion of unbound liquid from the grout region, could occur. This liquid return is driven by displacement caused by gas bubbles that form within the grout`s ...

Energy Technology Data Exchange (ETDEWEB)

The transport-relevant basic data recorded within the framework of a federation-wide transport data survey made in 1986 are the best-founded source at present for determining the transport volume of other radioactive materials in different economic areas of the Federal Republic of Germany. Due to the high recording rates, a sufficiently complete survey can be provided in particular with regard to the transport volume (e.g.transports/consignments/cargos, transport distance) - with the exception of transport by ship - for the ranges of application in reserach, medicine and technology. However, as regards the radiologically relevant basic data and transport modalities, the information supplied by the transporting agencies is incomplete. A table gives a comprehensive survey of type and scope of the transport volume of other radioactive materials in the Federal Republic of Germany (excluding the GDR) for ...

Science.gov (United States)

The calculated radioactive waste inventories of the Turkey Point pressurized water fission reactor (PWR) and the Starfire conceptual fusion tokamak are compared as a function of time from initial start-up to 10,000 years after decommissioning. Only materi...

Wastenet

... Top of page Testing Radiation coming from granite countertops results from natural radioactive material in the granite. Identifying the presence and concentration of radioactive elements in granite requires expensive and sophisticated portable instruments or laboratory equipment. These instruments and equipment require proper calibration, and interpretation of ...

Energy Technology Data Exchange (ETDEWEB)

On July 18, 2001, a freight train carrying hazardous (non-nuclear) materials derailed and caught fire while passing through the Howard Street railroad tunnel in downtown Baltimore, Maryland. The United States Nuclear Regulatory Commission (USNRC), one of the agencies responsible for ensuring the safe transportation of radioactive materials in the United States, undertook an investigation of the train derailment and fire to determine the possible regulatory implications of this particular event for the transportation of spent nuclear fuel by railroad. Shortly after the accident occurred, the USNRC met with the National Transportation Safety Board (NTSB), the U.S. agency responsible for determining the cause of transportation accidents, to discuss the details of the accident and the ensuing fire. Following these discussions, the USNRC assembled a team of experts from the National Institute of Standards ...

International Nuclear Information System (INIS)

Natural radioactive materials were used for detector calibration. We found that KCl is a very suitable material for this purpose. The efficiency curve shape was derived by using #gamma# ray lines of "2"1"4Bi normalised using a known quantity of KCl in the same geometry. The best fit was found by the least squares method. The summing correction coefficients for "2"1"4Bi are determined. (orig.).

International Nuclear Information System (INIS)

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

Energy Technology Data Exchange (ETDEWEB)

The paper deals with the disposal of radioactive waste and the plans for dealing with solid wastes of intermediate and low levels of activity, which are the responsibility of NIREX. NIREX is an executive body which co-ordinates the waste-disposal plans of the main radioactive waste producers. The disposal routes for the active wastes are described including the deep disposal of wastes containing material that will remain active for thousands of years. Requirements for deep burial are outlined with reference to the geology and hydrogeology of the site. Monitoring, maintenance and surveillance are mentioned for the protection of the public.

International Nuclear Information System (INIS)

This report describes a field-test program to determine the effectiveness of a polymeric wall sealant to reduce the escape of naturally occurring radioactive gas radon from the walls of an underground uranium mine into the ventilation air.

International Nuclear Information System (INIS)

A nation-wide survey of natural radioactivity in building materials was conducted during 1982-1984. Samples including industrial wastes, by-products and common building materials were collected from main building material manufactories in 29 provinces except Taiwan. The results of exposure rates, specific activities and release rate for "2"2"2Rn are presented. The specific activities of common materials are listed in declining order as follows: clay bricks > common concrete and sandstones > limes and ordinary cement. The highest level was found in breeze bricks made of stone coal, phosphogypsum and red mud with high intrinsic radioactivity. Therefore, these raw materials should be strictly controlled in manufacturing building materials. The measurement results also showed that the typical specific activities of ...

International Nuclear Information System (INIS)

The Nuclear Regulatory Commission (NRC), working with the National Institute of Standards and Technology (NIST), Pacific Northwest National Laboratory (PNNL), and the National Transportation Safety Board (NTSB), performed analyses to predict the response of various spent fuel transportation cask designs when exposed to a fire similar to that which occurred in the Howard Street railroad tunnel in downtown Baltimore, Maryland on July 18, 2001. The thermal performance of three different spent fuel cask designs (HOLTEC HI-STAR 100, TransNuclear TN-68, and NAC-LWT) was evaluated with the ANSYSR and COBRA-SFS analysis codes, utilizing boundary conditions for the tunnel fire obtained using NIST's Fire Dynamics Simulator (FDS) code. NRC Staff evaluated the potential for a release of radioactive material from each of the three transportation casks analyzed for the Baltimore tunnel fire scenario. The results of these analyses are ...

International Nuclear Information System (INIS)

When a nuclear power station was installed on the Meuse in central Belgium, the impact of thermal, radioactive, and chemical waste on the water of the Neuse and on its biocenoses was studied. Three successive periods of development of the channel bed and the flood plain in Belgium have occurred, and their hydrological, physicochemical, and ecological consequences have been examined. Since the last century, the ecosystem of the Meuse has undergone, due to the increasing activity of man, modifications of increasing importance: marked reduction of the water flow, a drastic increase in the suspended material being transported, a degree of eutrophication of the water, and the disturbance of the original floral and faunal communities. The causes of this evolution of the Meuse can be itemized as different types of human interference in descending order of importance: (1) occupation of the catchment area; (2) encroachment on the ...

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 is an austenitic Fe-Ni-Cr steel containing relatively minor but important amounts of carbon, aluminium and titanium. Special grades of alloy 800 known as 800H, 800HT and 800LC differ in the concentrations of these elements. In addition to these industrial specifications, further melts were prepared containing phosphorous or sulphur. Using a radioactive tracer method the bulk and grain-boundary diffusion of {sup 59}Fe was investigated in these alloys in the temperature range 800 to 1000 C. For evaluation of the diffusion profiles the approximation of Suzuoka was used, which considers the depletion of the tracer on the surface. By autoradiography it was confirmed that such depletion occurs. In alloy 800H the activation energy of grain-boundary diffusion of {sup 59}Fe was found to be (209{+-}17) kJ/mol; dissolved elements, especially phosphorous, increase the activation energy. The same materials - aged at 800 C for ...

International Nuclear Information System (INIS)

The leak before break (LBB) concept is difficult to apply to a structure with a thin tube that is immersed in a water environment. A heat exchanger in a nuclear power plant is such a structure. The present paper addresses an application of the LBB concept to a heat exchanger in a nuclear power plant. The minimum leaked coolant amount containing the radioactive material which can activate the radiation detector device installed near the heat exchanger is assumed. The postulated initial flaw size that cannot grow to the critical flaw size within the time period to activate the radiation detector is justified. In this case, the radiation detector can activate the warning signal caused by coolant leakage from initially postulated flaws of the heat exchanger. The nuclear plant can safely shutdown when this occurs. Since the postulated initial flaw size can not grow to the critical flaw size, the structural integrity of the heat ...

Energy Technology Data Exchange (ETDEWEB)

This text presents the annotations of all different articles of the law text concerning the sustainable development of radioactive materials and wastes. (A.L.B.)

CERN Document Server

Radioactive Waste

International Nuclear Information System (INIS)

Illicit trafficking of nuclear and other radioactive material has been an issue of concern since the first seizures in the early 1990s. By the end of 2004 Member States had confirmed 540 cases, while about another 500 remain unconfirmed. Most of the confirmed cases have a criminal dimension, even if they were not for known terrorist purposes. The attacks of September 2001 in the USA dramatically emphasized the requirement for the enhanced control and security of nuclear and other radioactive material. In response to a resolution by the IAEA General Conference in September 2002 the IAEA has adopted an integrated approach to protection against nuclear terrorism. This brings together IAEA activities concerned with the physical protection of nuclear material and nuclear installations, nuclear material accountancy, detection and response to illicit nuclear ...

International Nuclear Information System (INIS)

With the exception of some minerals, the specific activity of natural radioactive material is below 370 Bq/g, their handling thus not being subject to authorization or the duty of reporting according to section 4 para. 2 of the Radiological Protection Ordinance. Moreover, there is required no handling license for prospecting, mining and processing of radioactive minerals; they are subject to the procedures for the plans of operation of the mining laws of the Federal States. License-free handling of natural radioactive material may result in the production of radioactive waste, the disposal of which must be authorized according to sect. 47 of the Radiological Protection Ordinance if the specific activity exceeds the free amounts of column 4 in Table IV of Appendix IV by a factor of 10"-"4/g. This inconsistency is discussed by means of the following examples: (1) ...

International Nuclear Information System (INIS)

The characteristics of per-fluorocarbon compounds (PFC) are colorless, non-toxic, easily vaporized and nonflammable. Also, some of them are liquids of a high density, low surface tension, low latent heat and low specific heat. These particular chemical and physical properties of fluoro-organic compounds permit their use in very different fields such as electronics, medicine, tribology, nuclear and material science. The Sonatol process was developed under a contract with the DOE. The Sonatol process uses an ultrasonic agitation in a PFC solution that contains a fluorinated surfactant to remove radioactive particles from surfaces. Filtering the suspended particles allows the solutions to be reused indefinitely. They applied the Sonatol process to the decontamination of a heterogeneous legacy Pu-238 waste that exhibited an excessive hydrogen gas generation, which prevents a transportation of such a waste to a Waste Isolation Pilot Plant. Korea ...

International Nuclear Information System (INIS)

The use of finely powdered ion exchange resins improve loading of specific ion exchange materials with better performance but as such these materials are not suitable for column operation. However, by proper selection of ion exchange support medium, it is possible to get better product. The radioactive solution can be treated by suspending this material, stirring and allowing to settle. The present method gives DF in the range of 70 - 80 even after repeated use as compared to DF in the range of 5 to 10 by single conventional chemical treatment process. (author)

International Nuclear Information System (INIS)

Using high-resolution y-rays spectrometry, the natural radioactivity of 14 samples of natural and o manufactured Egyptian building materials have been investigated. The samples were collected from local market and construction sites. From the measured gamma-ray spectra, specific activities were determined. The radium equivalent activity in each sample was estimated. Radiological evaluations of these materials indicate that all materials meet the external gamma-ray dose limitation. Calculation of concentration indices by assuming a Markkanen room model is constructed from these materials, to find the excess gamma-ray dose taken over that received from the outdoors. The Austrian Standard ONORM S 5200 is used in testing the building materials.

Energy Technology Data Exchange (ETDEWEB)

A method is described for converting radioactive alkali metal into a low level disposable solid waste material. The radioactive alkali metal is atomized and introduced into an aqueous caustic solution having caustic present in the range of from about 20 wt % to about 70 wt % to convert the radioactive alkali metal to a radioactive alkali metal hydroxide. The aqueous caustic containing radioactive alkali metal hydroxide and CO{sub 2} are introduced into a thin film evaporator with the CO{sub 2} present in an amount greater than required to convert the alkali metal hydroxide to a radioactive alkali metal carbonate, and thereafter the radioactive alkali metal carbonate is separated from the thin film evaporator as a dry powder. Hydroxide solutions containing toxic metal hydroxide including one or more metal ions of Sb, As, ...

Science.gov (United States)

Testing was performed to determine the feasibility and processing characteristics of evaporation of actual Defense Waste Processing Facility (DWPF) recycle material. Samples of the Off Gas Condensate Tank (OGCT) and Slurry Mix Evaporator Condensate Tank (SMECT) were transferred from DWPF to the Savannah River National Lab (SRNL) Shielded Cells and blended with De-Ionized (DI) water and a small amount of Slurry Mix Evaporator (SME) product. A total of 3000 mL of this feed was concentrated to approximately 90 mL during a semi-batch evaporation test of approximately 17 hours. One interruption occurred during the run when the feed tube developed a split and was replaced. Samples of the resulting condensate and concentrate were collected and analyzed. The resulting analysis of the condensate was compared to the Waste Acceptance Criteria (WAC) limits for the F/H Effluent Treatment Plant (ETP). Results from the test were compared to previous testing ...

Science.gov (United States)

Several years ago, the AGARD Structures and Materials Panel selected ... flow separation appears to have occurred during the tests, and the angles of attack ...

Energy Technology Data Exchange (ETDEWEB)

Cementitious materials have physical and chemical properties that are well suited for the requirements of radioactive waste management. Namely, the materials have low permeability and durability that is consistent with the time frame required for short-lived radionuclides to decay. Furthermore, cementitious materials can provide a long-term chemical environment that substantially reduces the mobility of some long-lived radionuclides of concern for decommissioning (e.g., C-14, Ni-63, Ni-59). Because of these properties, cementitious materials are common in low-level radioactive waste disposal facilities throughout the world and are an attractive option for entombment of nuclear facilities. This paper describes design considerations for cementitious barriers in the context of performance over time frames of a few hundreds of years (directed toward short-lived ...

International Nuclear Information System (INIS)

The 5-th International conference 'Nuclear and Radiation Physics' was held in Almaty (Kazakhstan) 26-29 September 2005. Besides basic problems of nuclear and solid state physics the conference paid considerable attention to applied topics important for industry and science in Kazakhstan; they include fuel and construction materials for nuclear power production, new technologies and materials for their production, materials for hydrogen power production, handling and utilization of radioactive waste, analytical methods for combating with illicit trafficking of nuclear and radioactive materials, technologies for reduction and assessment of environmental risk from radiation-hazardous materials and sites, production and application of isotopes, application of nuclear technologies in medicine and industry. On the conference more than 300 papers ...

UK PubMed Central (United Kingdom)

From the gross conservation laws of thermodynamics in a convecting material we derive a bound on the ratio of the rate of production of mechanical or magnetic energy to the rate of internal radioactive...Full Text Available

International Nuclear Information System (INIS)

The document represents a guide for the external decontamination of persons accidentally radio contaminated due to the use, production or transport of radioactive materials. The general conditions, from the medical point of view, to be kept in mind, in the event of accidental overexposures as decontamination treatment and the handling of samples are detailed throughout report. The external contamination without injury in skin or with wound its considered. The distribution of measures and responsibilities for the therapy of the irradiated patients with radioactive materials are enumerated. The preparations of decontaminate solutions are detailed in this work. Moreover, forms for the reception, physical evaluation of the patient and external contamination are presented. (author)

International Nuclear Information System (INIS)

During a hypothetical severe incident in a nuclear power plant with core meltdown a large part of radioactive material is present as aerosol particles in the reactor containment. In current severe accident containment codes the potential influences of hydrogen combustions on the behaviour of aerosols are not considered. Among other effects dry resuspension can increase the aerosol concentration in the atmosphere. Already deposited aerosol material can be re-released into the containment atmosphere by atmospheric currents induced by hydrogen deflagrations or by other phenomena like steam explosions. The objective is to assess the possible influence of this dry resuspension effect on the radioactive source term. (author)

International Nuclear Information System (INIS)

For the interests of national security, many scientists who work in the field of nuclear forensic analysis have carried out extensive work in the past on the detection of radioactive material and attributions study, developed a series of scientific and technical means to trace and detect illicit circulation of nuclear materials used to weapons and other radioactive materials which impair public security. All these questions relate to physical, chemical, biological attribution of materials. The nuclear forensic analysis has already become a special, up-to-date sphere of learning. The goal of the study of nuclear forensics is to prevent terrorists from acquiring not only nuclear weapons but also mate- rials that can be used to make such weapons, including radioactive materials for nuclear power plants, and medical ...

Energy Technology Data Exchange (ETDEWEB)

A program is currently in progress at Argonne National Laboratory to evaluate and develop evaporator technology for concentrating radioactive waste streams. By concentrating radioactive waste streams, disposal costs can be significantly reduced. To effectively reduce the volume of waste, the evaporator must achieve high decontamination factors so that the distillate is sufficiently free of radioactive material. One technology that shows a great deal of potential for this application is being developed by LICON, Inc. In this program, Argonne plans to apply LICON`s evaporator designs to the processing of radioactive solutions. Concepts that need to be incorporated into the design of the evaporator include, criticality safety, remote operation and maintenance, and materials of construction. To design an effective process for concentrating waste streams, both ...

Energy Technology Data Exchange (ETDEWEB)

The US investigated the use of {sup 233}U for weapons, reactors, and other purposes from the 1950s into the 1970s. Based on the results of these investigations, it was decided not to use {sup 233}U on a large scale. Most of the {sup 233}U-containing materials were placed in long-term storage. At the end of the cold war, the US initiated, as part of its arms control policies, a disposition program for excess fissile materials. Other programs were accelerated for disposal of radioactive wastes placed in storage during the cold war. Last, potential safety issues were identified related to the storage of some {sup 233}U-containing materials. Because of these changes, significant activities associated with {sup 233}U-containing materials are expected. This report is one of a series of reports to provide the technical bases for future decisions on how to manage this ...

Energy Technology Data Exchange (ETDEWEB)

An inorganic particulate adsorbent of a titania-alumina is described for treating a superheated water containing radioactive materials such as cobalt ions, which is free from release of corrosive impruities, and which has a high adsorption capacity of radioactive materials and a high mechanical strength is prepared by hydrolyzing a titanium alkoxide and an aluminum alkoxide, thereby forming a hydrous titanium oxide and a hydrous aluminum oxide, respectively; precalcining the hydrous titanium oxide and aluminum oxide, mixing and molding the resulting titania and alumina into a particulate mixture thereof having a titania mole fraction of 0.2 to 0.9, and calcining the particulate mixture at 500/sup 0/-700/sup 0/C. This absorbent is effectively used in treat boiling water-type nuclear reactor core-circulating water to remove radioactive substances therefrom.

Energy Technology Data Exchange (ETDEWEB)

The research carried out in Canada in the design of containers for the disposal of radioactive waste has focussed on spent nuclear fuel, even though the quantities of other currently stored radioactive wastes are substantially greater. Research carried out at the Royal Military College of Canada on the effects of mixed fields of radiation on high polymer adhesives and composite materials has shown that some polymers are quite resistant to radiation and could well serve in the fabrication of radioactive waste disposal containers. The purpose of this research was to determine if thermoplastic polymers could be used as superior materials to replace metals in the application of low and intermediate level radioactive waste disposal containers. Polymers have the advantage that they do not corrode like metals. The experimental methods, used in this research, focused on ...

CERN Document Server

The Principles of Radioactive Waste Management

International Nuclear Information System (INIS)

Large-scale decommissioning of Russian nuclear-powered submarines (NPS) and their utilization prospects gave rise to numerous complicated scientific and technical, as well as economic, problems. Problems of handling of radioactive equipment from the reactor compartments (RC) are among the vital ones, arousing a growing concern with the public. Without solution of the problems the processes of NPS utilization can not be considered completed. It involves potential hazard, for the environment both from NPS being paid up (temporal on-float storage) with unloaded spent nuclear fuel (SNF), and RC, cut from submarine hull, containing highly radioactive equipment and materials but no SNF. Diverse variations of the concept of reactor compartment handling of NPS subject to, utilization are possible, but, in principle, there are essentially two variants: (1) RC utilization directly in the course of NPS utilization, envisaging removal ...

International Nuclear Information System (INIS)

Those who for a long time have been performed studies with relation by affinity with radioactivity, have in mind that several basic concept to nuclear sciences are of public or general knowledge assuming that in the market there exist a wide stock of diffusion material. Nevertheless, for the attained results in this work, we have seen that there exist great disinformation about to radioactivity its peaceful uses and particularly with a logotype which indicate the presence of radioactive material. The study was carried out in the considering that a probabilistic sampling in the Mexico city will permit to estimate the proportion of the population who knows the International symbol which we are talking about and will give a representative opinion on radioactivity and will indicate the information means with a better acceptation. First of all we proceeded to the ...

International Nuclear Information System (INIS)

Liquid radioactive raffinates from nuclear fuel reprocessing at the Idaho National Engineering and Environmental Laboratory were solidified, or calcines, in a fluidized bed reactor at approximately 500 C to form a dry granular material. This calcine has been provisionally stored near-surface in concrete-encased stainless steel bins at the Idaho Nuclear Technology Engineering Center. Research addressing the permanent immobilization of radioactive waste has been ongoing. One option is to separate the radioactive constituents from the calcine, thereby reducing the radioactive waste volume to be ultimately stored at a national nuclear waste repository. Nitric acid dissolution of the calcine is a key front-end unit operation in the separations option. In order to design calcine dissolution equipment, quantification of dissolution reaction rate parameters is required. A ...

Energy Technology Data Exchange (ETDEWEB)

Areas with elevated levels of radioactivity were found throughout both residences, as well as on the surrounding property. Contamination was also found in the garage behind the 105 East structure. The 105 East residence had substantially more contamination than the 107 East residence, as was expected. The chimneys, particularly the rear chimney, from the 105 East residence had extensive contamination, indicating that contaminated materials may have been burned at the site. The high background radiation emanating from this residence made it difficult to establish the relatively lower levels of contamination in the 107 East residence. The property surrounding the 105 East residence was found to have substantial contamination scattered throughout, with the highest level occurring in the backyard. The soil surface contamination seemed to drop markedly (but not entirely) at the property lines. The property surrounding 107 East ...

International Nuclear Information System (INIS)

Concentrations of 226Ra, 232Th, and 40K measured in bauxite waste, local building materials, and soils are presented and used in model equations to estimate the effective gamma dose-equivalent increments over background in the center of a standard-sized room in a prototype house. Calculated and measured values compare reasonably well.

Science.gov (United States)

To estimate the waste management needs of a fusion power reactor, a scheme for handling radioactive waste from a fusion plant has been devised. The handling scheme proceeds with radioactive waste, primarily from blanket replacement, being stored on-site; waste in cooled and shielded casks is then isolated off-site; finally, the materials are recycled. Using activities and component lifetimes supplied by designers, several conceptual fusion power reactors have been analyzed and their waste streams compared to fission reactors with regard to total activity, specific activity, and lifetimes of activity.

International Nuclear Information System (INIS)

Selection of detailed-items for Periodic Safety Review on PWR radwaste management system, the main component could be faithfully clarified according to the purpose of establishment on each system and basic purpose. It is proper to select detailed-items those of radioactivities in the reactor coolant activity levels and the released volume of liquid and gaseous radioactive material on safety performance. It's also proper to select solid radwaste production quantities as detailed-item that it would be predict the next ten years trends after PSR.

International Nuclear Information System (INIS)

This feature articles described a concept and technical problems of geological disposal of high-level radioactive waste in the civil engineering. It consists of six papers such as the present statues and subjects of geological disposal by KITAYAMA Kazumi, the diastrophism, igneous activity, and upheaval and erosion by YAMAZAKI Haruo, the groundwater flow and evaluation of nuclear transfer by IJIRI Yuji, evaluation of alteration of cement materials in the ultra-long period by HAGA Kazuko, The Mizunami Underground Research Laboratory in course of construction by SAKAMAKI Masanori, and interview of the ninetieth president of JSCE (Japan Society of Civil Engineers), he places his hope on JSCE and civil engineers by KISHI Kiyoshi. (S.Y.)

International Nuclear Information System (INIS)

A quantitative comparison of tissue distribution and excretion of an orally administered sublethal dose of [3H]diacetoxyscirpenol (anguidine) was made in rats and mice 90 min, 24 hr, and 7 days after treatment. Total recoveries of 95-100% were obtained. Approximately 90% of the dose was excreted in urine and feces during the first 24 hr with a feces:urine ratio of about 1:4.5 in both species. Carcass and tissue radioactivity dropped rapidly during the first 24 hr but remained relatively constant at low, but detectable, levels over the course of the experiment. Few substantive interspecies differences were noted in tissue distribution. At 90 min the highest percentage of dose was in tissues involved in sequestering diacetoxyscirpenol because of high body water/lipid content or the absorption, metabolism, or excretion of the toxin. The rank order of these tissues was generally stable over the course of the experiment. When data were expressed as specific ...

Energy Technology Data Exchange (ETDEWEB)

The macroscopic behavior of magnetostrictive materials results from domain evolutions occurring at a microscopic scale. The author shows how to compute magnetization and magnetostriction curves by appraising the behavior of the underlying microstructures. The method hinges on an averaging device (Young measures), which allows one to pass from the microscopic to the macroscopic scale. He takes into account the kinematical constraints on the accommodation of elastic effects, and he highlights the role of material symmetry in the selection of energetically optimal microstructures.

International Nuclear Information System (INIS)

Radioactive waste shipping and receiving facilities presently planned for commercial and defense high-level nuclear waste will handle waste packages at frequencies far in excess of those in common practice today. If current limits for radiation levels at the cask surface and current handling methods are used, high cumulative personnel exposure to ionizing radiation is projected to occur. To reduce these exposure levels, alternate handling methods are being developed and demonstrated. The production nature of cask receiving operations, suggests commercial robotics be incorporated into a remote handling system to reduce predicted worker exposure to acceptable levels while maintaining or increasing throughput. The first phase of cask handling system development culminated in a proof-of-principle test demonstrating the feasibility of performing cask receiving and unloading operations in a remote and partially automated manner.

Energy Technology Data Exchange (ETDEWEB)

The estimation of radiation dose to man from either external or internal exposure to radionuclides requires a knowledge of the energies and intensities of the atomic and nuclear radiations emitted during the radioactive decay process. The availability of evaluated decay data for the large number of radionuclides of interest is thus of fundamental importance for radiation dosimetry. This handbook contains a compilation of decay data for approximately 500 radionuclides. These data constitute an evaluated data file constructed for use in the radiological assessment activities of the Technology Assessments Section of the Health and Safety Research Division at Oak Ridge National Laboratory. The radionuclides selected for this handbook include those occurring naturally in the environment, those of potential importance in routine or accidental releases from the nuclear fuel cycle, those of current interest in nuclear medicine and fusion reactor ...

International Nuclear Information System (INIS)

On July 18, 2001, a freight train carrying hazardous (non-nuclear) materials derailed and caught fire while passing through the Howard Street railroad tunnel in downtown Baltimore, Maryland. The United States Nuclear Regulatory Commission (USNRC), one of the agencies responsible for ensuring the safe transportation of radioactive materials in the United States, undertook an investigation of the train derailment and fire to determine the possible regulatory implications of this particular event for the transportation of spent nuclear fuel by railroad. Shortly after the accident occurred, the USNRC met with the National Transportation Safety Board (NTSB, the U.S. agency responsible for determining the cause of transportation accidents), to discuss the details of the accident and the ensuing fire. Following these discussions, the USNRC assembled a team of experts from the National Institute of Standards ...

International Nuclear Information System (INIS)

The Chuetsu-oki Earthquake strongly shook the Kashiwazaki-Kariwa Nuclear Power Station with the ground motions exceeding the design values. The incidents include a fire breakout of the Unit 3 transformer, a release of spilled water containing small amount of radioactive materials to the non-radiation control area and subsequently to the environment at Unit 6, and a release of radioactive material from the main turbine condenser through the main stack of Unit 7 due to the delay stooping the turbine gland steam ventilator by the operator in manually, while every unit in operation was safety shutdown in the automatic mode ensuring the three fundamental safety functions of (a) reactivity control, (b) removal of heat from the core and (c) confinement of radioactive materials. Following integrity evaluation and performance testing of the overall plant, seismic safety ...

UK PubMed Central (United Kingdom)

Social support is a critical, yet underutilized resource when undergoing cancer care. Underutilization occurs in two conditions: (a) when patients fail to seek out information, material assistance,...Full Text Available

International Nuclear Information System (INIS)

Nuclear forensics can provide information about the history, intended use and potentially the origin of nuclear or radioactive material. For these reasons, it is an important tool for improving nuclear security and combating illicit trafficking of nuclear and other radioactive materials. The IAEA is currently working on enhancing knowledge, techniques, procedures and cooperation in the field of nuclear forensics. Some of the work currently being undertaken by the IAEA includes the development of a five day training workshop on basic methods for radiological crime scene activities, to ensure adequate control of evidence, including for nuclear forensics purposes, a coordinated research project on the application of nuclear forensics in illicit trafficking, and a proposal for international cooperation with nuclear forensics databases and the development of guidelines for establishing databases. Nuclear ...

Energy Technology Data Exchange (ETDEWEB)

This paper reviews different helium-cooled first wall and blanket designs; and compares the selection of structural materials. The authors found that the solid breeder, SiC-composite material option generates the lowest amount of induced radioactivity and afterheat and has the highest temperature capability. When combined with the direct cycle gas turbine system, it has the potential to be the most economical fusion system and can compete with advanced fission reactors. When compared to martensitic steel and V-alloy, SiC-composite is the least developed of these three structural materials, a focused development effort will be needed. Fundamental research has begun in addressing the issues of optimized composite materials, irradiation effects, leak tightness and low activation braze materials. Development of helium-cooled high heat flux components and further ...

International Nuclear Information System (INIS)

Following the 1986 Chernobyl accident there was an understandable increase in public interest in nuclear accidents and emergency planning for them. It became clear that the broad nature, timing and scale of the radiological hazard presented by such accidents was, however, little understood. This Paper sets out in simple terms the basic features of the radiological hazard to persons in the vicinity of a nuclear power plant should a serious accident occur. The Paper starts by stressing the difference between faults -events that may occur relatively frequently - and accidents -unplanned releases of radioactivity that are by design extremely unlikely events. The Paper examines the significance of different exposure pathways and relates them to the protective measures (countermeasures) that may be taken. These countermeasures include sheltering, evacuation and the consumption of stable iodine tablets. The Paper illustrates the ...

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the work that was completed in FY 1992 on the program {open_quotes}Technology Development for Concentrating Process Streams.{close_quotes} The purpose of this program is to evaluate and develop evaporator technology for concentrating radioactive waste and product streams such as those generated by the TRUEX process. Concentrating these streams and minimizing the volume of waste generated can significantly reduce disposal costs; however, equipment to concentrate the streams and recycle the decontaminated condensates must be installed. LICON, Inc., is developing an evaporator that shows a great deal of potential for this application. In this report, concepts that need to be incorporated into the design of an evaporator operated in a radioactive environment are discussed. These concepts include criticality safety, remote operation and maintenance, and materials of construction. Both solubility and ...

International Nuclear Information System (INIS)

It is becoming increasingly evident that a linkage needs to exist between the siting of emergency response units and the routing of high level radioactive waste shipments. It is important to position the response teams so that the most efficient and effective emergency response can be provided. But the data needed to solve the siting problem are fragmented. This paper identifies the weak points in the data already available and suggests ways in which the data can be strengthened in a cost-effective manner. Among the weakest areas are estimates of the time required for various response events to occur, such as notification time, mobilization time, travel time, and containment time.

International Nuclear Information System (INIS)

Population distribution, atmospheric change, X/Q, characteristics of terrestrial ecosystem around Seoul site were surveyed. Environmental radiation and radioactivities such as gross#alpha#, gross#beta#, Cs-137, Sr-90 and H-3 of various environmental samples were analyzed. The values of environmental radiation dose tended to increase gradually in the light of the recent five years' results of environmental radiation monitoring around the nuclear power plants from 1980 to 1984, however, the changes were not significant. In addition, continuous assessment of environmental radiation monitoring on the roofs of main building and life science building at KAERI showed that the environmental radiation dose tended to increase a little during the night time. Judging from the above results, it is concluded that environmental contamination level by radioactive materials could be ignored in the case of radioisotope production or ...

International Nuclear Information System (INIS)

Natural minerals and some industrial wastes are used as low cost sorbents for removal of metal ions from effluent streams. Apatite as natural mineral and red mud as an industrial waste have been tested for their sorption properties with respect to two important fission products "1"3"7Cs and "9"0Sr. Their ion exchanging capacity was tested after every 4 hours till 24 hours. The material gets saturated after 4-8 hours. Hence these materials can be considered for treating in treating LLW before discharge, industrial waste treatment and as backfill or admixture material for shallow land repository. (author)

Energy Technology Data Exchange (ETDEWEB)

An indoor survey in order to estimate the population exposure in five towns of an Italian Region is presented. A particular methodology for the campaign was planned and is being applied. Gamma spectrometry of building materials, exposure rate measurements indoors and outdoors and radon concentration measurements indoors were taken with different techniques. A correlation was found between mean gamma exposure rate and mean radon concentration in the houses investigated. An evaluation of mean effective dose equivalents for the inhabitants of the five towns is reported.

Energy Technology Data Exchange (ETDEWEB)

The Formerly Utilized Sites Remedial Action Program (FUSRAP) is to evaluate the radiological conditions at former MED-US AEC sites. Purpose of the Ocean FUSRAP program is to assess the feasibility of ocean disposal of FUSRAP waste which contains trace natural radioactive materials. This paper presents soil characterization information on the Middlesex, NJ, Sampling Plant site, and reports preliminary ocean dispersion calculations. (DLC)

Energy Technology Data Exchange (ETDEWEB)

Guidelines for uranium residual radioactive material in soil were derived for the B&T Metals Company site in Columbus, Ohio. This site has been identified for remedial action under the US Department of Energy`s (DOE`s) Formerly Utilized Sites Remedial Action Program (FUSRAP). Single-nuclide and total-uranium guidelines were derived on the basis of the requirement that following remedial action, the 50-year committed effective dose equivalent to a hypothetical individual living or working in the immediate vicinity of the site should not exceed a dose constraint of 30 mrem/yr for the current use and likely future use scenarios or a dose limit of 100 n-mrem/yr for less likely future use scenarios. The DOE residual radioactive material guideline computer code, RESRAD, was used in this evaluation. RESRAD implements the methodology described in the DOE manual for establishing residual ...

International Nuclear Information System (INIS)

The invention concerns a container for the long term storage of irradiated nuclear reactor fuel elements, which consists mainly of a basic body, at least one lid and an outside ring shaped lid tightening device, which acts on the basic body and the lid and holds the contact surface of the lid tight against the contact surface of the basic body, where the basic body, lid and the lid tightening device consist of corrosion-proof materials. (orig./HP).

International Nuclear Information System (INIS)

Theft, illegal possession, smuggling, or attempted unauthorized sale of nuclear and radiological materials remains a worldwide problem. The Nuclear Smuggling International Technical Working Group (ITWG) has adopted a model action plan to guide investigation of these cases through a systematic approach to nuclear forensics. The model action plan was recently documented and provides recommendations concerning incident response, collection of evidence in conformance with required legal standards, laboratory sampling and distribution of samples, radioactive materials analysis, including categorization and characterization of samples, forensics analysis of conventional evidence, and case development including interpretation of forensic signatures. (author)

International Nuclear Information System (INIS)

Radiation exposure of members of the public can be increased appreciably by the use of building materials containing above-normal levels of natural radioactivity. This phenomenon has attracted attention in recent years, and in this review, an attempt is made to the quantify exposures incurred under various circumstances. The second section of the review is a general survey of those building materials, mostly industrial wastes, that have aroused interest in Member countries. The probability that environmental pressures may cause such wastes to be used more and more by building industries may lead to similar situations in the future. Other review material of a relevant nature is described in the third section. Primordial radionuclides only are considered here. They are: potassium-40 (K-40); radium-226 (Ra-226) and its decay products; the series headed by thorium-232 (Th-232). The important radiological ...

Energy Technology Data Exchange (ETDEWEB)

The Savannah River Site (SRS) is currently developing a new facility, the Actinide Packaging and Storage Facility (APSF), to process and store legacy materials from the United States nuclear stockpile. A variety of materials, with a variety of properties, packaging and handling/storage requirements, will be processed and stored at the facility. Since these materials are hazardous and radioactive, automation will be used to minimize worker exposure. Other benefits derived from automation of the facility include increased throughput capacity and enhanced security. The diversity of materials and packaging geometries to be handled poses challenges to the automation of facility processes. In addition, the nature of the materials to be processed underscores the need for safety, reliability and serviceability. The application of automation in this facility must, ...

Energy Technology Data Exchange (ETDEWEB)

The Savannah River Site (SRS) is a key installation for the production and research of nuclear materials for national defense and peace time applications and has been operating a full nuclear fuel cycle since the early 1950s. Wastes generated include high level radioactive, transuranic, low level radioactive, hazardous, mixed, sanitary, and aqueous wastes. Much progress has been made during the last several years to reduce these wastes including management systems, characterization, and technology programs. The reduction of wastes generated and the proper handling of the wastes have always been a part of the Site's operation. This paper summarizes the current status and future plans with respect to waste reduction to waste reduction and reviews some specific examples of successful activities.

British Library Electronic Table of Contents (United Kingdom)

Crystalline silicotitanate inorganic ion exchanger, with a sitinakite structure is candidate material for remediation of aqueous nuclear waste streams. The syntheses of crystalline silicotitanate (CST) and Nb-substituted crystalline silcotitanate (Nb-CST) were carried out under hydrothermal conditions and the products were characterized using techniques viz., XRD, SEM/EDS, DTA/TGA, surface area respectively. Batch experiments were carried out to study the kinetics of uptake of 137Cs and 90Sr, to estimate the decontamination factor (DF) values and distribution coefficients (K d) for the above synthesized CST and Nb-CST samples from actual radioactive waste solutions. The DF values for uptake of Cs and Sr by Nb-CST after 24?h of equilibration was 355 and 136 whereas for CST it was found to b...

Energy Technology Data Exchange (ETDEWEB)

Natural radioactive materials are present in all geological rocks in varying amounts, they are easily mobilized in the environment, and can reach hazardous radiological levels under certain conditions, requiring precautions to be taken. The present study deals with 50 geological samples of local (Tushki and Kalabsha in upper Egypt) and imported (southeast Asia and Turkey) kaolin types. The samples were analyzed by gamma-ray spectroscopy using a HPGe detector. The activity concentrations of {sup 232}Th and {sup 238}U series and {sup 40}K and the contents (in ppm) are given. The radium equivalent activity varied from 187.8 to 10185.19 Bq/kg. {sup 137}Cs was found in a range of 0.23-8.53 Bq/kg, for the local samples. The kaolin in Tushki area was suitable for industrial use.

International Nuclear Information System (INIS)

The Hanford Waste Vitrification Plant Project has been established to convert the high-level radioactive waste associated with nuclear defense production at the Hanford Site into a waste form suitable for disposal in a deep geologic repository. The Hanford Waste Vitrification Plant will mix processed radioactive waste with borosilicate material, then heat the mixture to its melting point (vitrification) to forin a glass-like substance that traps the radionuclides in the glass matrix upon cooling. The Hanford Waste Vitrification Plant Quality Assurance Program has been established to support the mission of the Hanford Waste Vitrification Plant. This Quality Assurance Program Description has been written to document the Hanford Waste Vitrification Plant Quality Assurance Program.

Energy Technology Data Exchange (ETDEWEB)

A review of the various solidification agents and techniques that are currently available or potentially applicable for the solidification of low-level radioactive wastes is presented. An overview of the types and quantities of low-level wastes produced is presented. Descriptions of waste form matrix materials, the wastes types for which they have been or may be applied and available information concerning relevant waste form properties and characteristics follow. Also included are descriptions of the processing techniques themselves with an emphasis on those operating parameters which impact upon waste form properties. The solidification agents considered in this survey include: hydraulic cements, thermoplastic materials, thermosetting polymers, glasses, synthetic minerals and composite materials. This survey is part of a program supported by the United States Department of Energy's Low-Level ...

International Nuclear Information System (INIS)

Thermoluminescence (TL) dosimetry was used to measure dose effects on the raw stock material of borosilicate container glass from different geographical locations. Effects were studied at times up to 60 days post-irradiation at doses from 0.15 to 20 Gy. The minimum detectable dose using this technique was estimated to be 0.15 Gy which is roughly equivalent to a 24 hr irradiation 1 cm from a 50 ng source of 60Co. Two peaks were identified in the TL glow curve, a relatively unstable peak around 125 C and a more stable peak around 225 C. Differences in TL glow curve shape and intensity were also observed for the glasses from different geographical origins. We investigate radiation induced defects in glass to further develop the technique of intrinsic dosimetry - the measurement of the total absorbed dose received by the walls of a container holding radioactive material. Intrinsic dosimetry is intended to be used as an ...

International Nuclear Information System (INIS)

The Transportation Legislative Database (TLDB) is an on-line information service containing detailed information on legislation and regulations regarding the transportation of radioactive materials in the United States. The system is dedicated to serving the legislative and regulatory information needs of the US Department of Energy and other federal agencies; state, tribal, and local governments; the hazardous materials transportation industry; and interested members of the general public. In addition to the on-line information service, quarterly and annual Legal Developments Reports are produced using information from the TLDB. These reports summarize important changes in federal and state legislation, regulations, administrative agency rulings, and judicial decisions over the reporting period. Information on significant legal developments at the tribal and local levels is also included on an as-available basis. ...

Energy Technology Data Exchange (ETDEWEB)

The characterization data obtained to date are described for Approved Testing Material 104 (ATM-104), which is spent fuel from Assembly DO47 of the Calvert Cliffs Nuclear Power Plant (Unit 1), a pressurized-water reactor. This report is one in a series being prepared by the Materials Characterization Center at Pacific Northwest Laboratory (PNL) on spent fuel ATMs. The ATMs are receiving extensive examinations to provide a source of well-characterized spent fuel for testing in the US Department of Energy Office of Civilian Radioactive Waste Management (OCRWM) Program. ATM-104 consists of 128 full-length irradiated fuel rods with rod-average burnups of about 42 MWd/kgM and expected fission gas release of about 1%. A variety of analyses were performed to investigate cladding characteristics, radionuclide inventory, and redistribution of fission products. Characterization data include (1) fabricated fuel design, irradiation ...

CERN Document Server

Regulatory Control of Radioactive Waste Management

International Science & Technology Center (ISTC)

Methods of Decontamination, Utilization, and Deactivation of Liquid Radioactive Wastes

International Nuclear Information System (INIS)

Radioactive iron is used to follow up some haematologic indices in birds infected with irradiated spirochetes of the Borrelia anderina species. Use is made of a total of 90 cockerels, aged two months, divided into three groups: 1st group - cockerels inoculated with spirochetes that had been gamma-irradiated at the rate of 40000 R; 2nd group - cockerels inoculated with untreated spirochetes; and 3rd group - normal cockerels. The infective material consisted of strain Rouen spirochetes of the Pamoukchii serotype. Radiometric studies were also carried out for establishing to what extent radioactive iron is incorporated in the erythrocytes and is deposited in the liver, spleen, and marrow of the investigated birds. Classical methods of investigation were employed to determine the erythrocyte, leukocyte, and thrombocyte counts, the haemoglobin content (after Sahli) as well as the erythrocyte pack after the method of Todorov. It ...

Energy Technology Data Exchange (ETDEWEB)

Natural radioactive materials under certain conditions can reach hazardous radiological levels. The natural radionuclide ({sup 238}U, {sup 232}Th, {sup 40}K) contents of rock samples at various locations in the North Tushki area were investigated using gamma-spectrometric analysis. Estimates of the measured radionuclide content have been made for the absorbed dose rate of gamma radiation. The equivalent radium (R{sub eq}) and the external hazard index (H{sub ex}) which resulted from the natural radionuclides in soil are also calculated and tabulated. The studied samples have been collected from various rock exposures in the North Tushki area. The distribution of major oxides, U and Th were studied. It is found that the enrichment and depletion of the major oxides are mainly due to the effect of hydrothermal alteration, which caused mobility of some major oxides, which increases some elements and decreases others. It is important to mention that ...

Energy Technology Data Exchange (ETDEWEB)

Because of past military operations, lack of upkeep and looting there are now enormous radioactive waste problems in Iraq. These waste problems include destroyed nuclear facilities, uncharacterized radioactive wastes, liquid radioactive waste in underground tanks, wastes related to the production of yellow cake, sealed radioactive sources, activated metals and contaminated metals that must be constantly guarded. Iraq currently lacks the trained personnel, regulatory and physical infrastructure to safely and securely manage these facilities and wastes. In 2005 the International Atomic Energy Agency (IAEA) agreed to organize an international cooperative program to assist Iraq with these issues. Soon after, the Iraq Nuclear Facility Dismantlement and Disposal Program (the NDs Program) was initiated by the U.S. Department of State (DOS) to support the IAEA and assist the Government of Iraq (GOI) in ...

Energy Technology Data Exchange (ETDEWEB)

The Formerly Utilized Sites Remedial Action Program (FUSRAP) of the Department of Energy is designed to identify and evaluate the radiological conditions at sites formerly used by the Corps of Engineers Manhattan Engineer District and the US Atomic Energy Commission. Where required, remedial action will be instituted to remove potential restrictions on the use of the sites due to residual low-level radioactive contamination. A total of 31 sites that may require remedial action has been identified. The purpose of the Ocean FUSRAP Program, which began in March 1981, is to assess the technical, environmental, and institutional feasibility of disposing, in the ocean and on the ocean floor, of FUSRAP soil and rubble which contains traces of natural radioactive materials. The initial focus has been on the Middlesex, New Jersey, Sampling Plant site and surrounding properties, which contain on the order of 100,000 metric tons of ...

Energy Technology Data Exchange (ETDEWEB)

It is the Office of protection against the ionizing radiations (O.P.R.I.) who alerted the A.C.R.O. that a new ruthenium incident had arisen to the factory Cogema - La Hague on October 31., 2001. The A.C.R.O. immediately made a campaign of analyses the results of which are presented in this note. The previous similar incident dates May 18., 2001. A loss of depression in the workshop R7 of the factory UP2-800 specialized in the vitrification had brought an unchecked release, by one of the smokestacks, composed essentially of radioactive ruthenium and rhodium; the evacuated activity was estimated by the operator at approximately 11 MBq. The measures in environment made by the A.C.R.O. had led the association to question the Authority of Nuclear Safety about the total quantity of release announced by the operator. Having presented the results of the measures of radioactivity in the environment made following the incident of 31. october 2001, an ...

International Nuclear Information System (INIS)

The authors present arguments against nuclear energy and pro renewable energy sources. Thus, the water used in Uranium mining and primary ore processing becomes contaminated in long lived radioisotopes and so a threat for local ecosystems and communities. Then, during the fabrication, enrichment, and handling of nuclear fuel the workers are exposed to radiations and dangerous accidental radioactive leaks can occur. But, by far, the most menacing aspect of nuclear power exploitation remains the human errors in operating the nuclear plants which can result in major accidents like that from Chernobyl which spread radioactivity all over the Europe. The equipment used in nuclear facilities which is highly contaminated as well as the burned fuel implies transportation and long term storage which also present high risks. The major advantage of the nuclear energy consists in its very low environment impact and its null contribution ...

International Nuclear Information System (INIS)

Red mud is a waste and tail material from primary aluminum production, and is named for its color, coming from its iron oxide content. The quantity of red mud is almost equal to the primary aluminum production and leads to a considerable environmental issue. Red mud of the ETI Seydisehir Aluminum Plant is considered as detrimental waste for storage due to its content of various metal oxides, elements and caustics. This detrimental effect is classified into two groups: first, environmental health and second, the cost of storage. In order to minimize the negative effect of red mud, there have been or are presently many investigations carried out on usage of red mud in building materials. However, no effective way of utilizing red mud has yet been found. In this study domestic red mud was investigated and chemical analyses were performed by EDAX and XRF techniques. Radioactivity of the samples was also measured with gamma ...

Science.gov (United States)

This paper focuses on a factorial-based design strategy. The approach provides an efficient and statistically reliable means for assessing the influence of multivariable effects. It is applied to the detection and evaluation of damage in impacted composite sandwich panels. The experimental results obtained from this test strategy are utilized to form an empirical response function. The resulting polynomial relates damage area to residual compression strength at values of independent variables for which testing did not occur. The response function also identifies nonlinear interaction effects of key variabes that cannot be easily ascertained by traditional single-variable test strategies. Independent variables evaluated include core thickness, number of face sheet plys and impact energy. The methodology presented allows the designer to predict with more confidence the damage tolerance of a composite material component, and the analyst to more ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Under eons of evolutionary and environmental pressure, biological systems have developed strong and lightweight peptide-based polymeric materials by using the 20 naturally occurring amino acids as principal monomeric units. These materials outperform their man-made counterparts in the following ways: 1)-multifunctionality/tunability, 2)-adaptability/stimuli-responsiveness, 3)-synthesis and processing under ambient and aqueous conditions, and 4)-recyclability and biodegradability. The universal design strategy that affords these advanced properties involves -bottom-up- synthesis and modular, hierarchical organization both within and across multiple length-scales. The field of -biomimicry--elucidating and co-opting nature-s basic material design principles and molecular building blo...

International Nuclear Information System (INIS)

A review is presented of the literature through 1977 on the uses of radioactive lead isotopes in metabolic studies in man, animals, and plants. These studies have been done mainly with the naturally-occurring, long-lived (22-yr half life) "2"1"0Pb, but a few were with 53-hr "2"0"3Pb or 10.6-hr "2"1"2Pb. Such studies have made possible estimates of the metabolic parameters of lead in man and animals, such as intestinal absorption, the ratio of fecal-to-urinary excretion of endogenous lead, residence time of lead in the body and in various organs, and the distribution in the body (skeleton, liver, kidney, and blood). Subsequently, these parameters and data have been used to trace the sources of lead for man, such as those from the atmosphere, food, cigarette smoke, and automobile exhaust.

Energy Technology Data Exchange (ETDEWEB)

A process and apparatus for solidifying radioactive waste liquid containing dissolved and/or suspended solids is disclosed. The process includes chemically treating for pH adjustement and precipitation of solids, concentrating solids with a thin-film evaporator to provide liquid concentrate containing about 50% solids, and drying the concentrate with heated mixing apparatus. The heated mixing apparatus includes a heated wall and working means for shearing dried concentrate from internal surfaces and subdividing dry concentrate into dry, powdery particles. The working means includes a rotor and helical means for positively advancing the concentrate and resulting dry particles from inlet to outlet of the mixing apparatus. The dry particles may also be encapsulated in a matrix material. Entrained particles in the vapor stream from the evaporator and mixer are removed in an integral particle separator and the vapor is subsequently condensed and may ...

Energy Technology Data Exchange (ETDEWEB)

With the recent advance of the utilization of nuclear energy in a large scale, social interest is being focussed in the potential risk which the nuclear technology will accompany. Especially after the accidents in Chernobyl and other nuclear facilities, serious anxiety to the utilization of nuclear energy is prevailing among the general public. In order to meet the anxiety and distrust of the population in the use of the nuclear power, the health effect or risk which radioactive materials released into the environment will bring about should be comprehensively and properly evaluated, and then should be widely reported to the population. The development of HESANS code system (Health and Environmental Safety Assessment Network System) was planned to set up such a comprehensive computer code that covers a whole pathway of radioactive material from its release to estimates of derived health effects in the ...

Energy Technology Data Exchange (ETDEWEB)

A method for encapsulating and immobilizing waste for disposal. Waste, preferably, biologically, chemically and radioactively hazardous, and especially electronic wastes, such as circuit boards, are placed in a crucible and heated by microwaves to a temperature in the range of approximately 300{degrees}C to 800{degrees}C to incinerate organic materials, then heated further to a temperature in the range of approximately 1100{degrees}C to 1400{degrees}C at which temperature glass formers present in the waste will cause it to vitrify. Glass formers, such as borosilicate glass, quartz or fiberglass can be added at the start of the process to increase the silicate concentration sufficiently for vitrification.

International Nuclear Information System (INIS)

This paper presents a rationale for and a summary of tasks and missions to which mobile and stationary robots and other teleoperator-controlled devices could be assigned in response to the accidental release of radioactive and other hazardous/toxic materials to the environment. Many of these vehicles and devices currently support operation and maintenance of nuclear power plants and other nuclear industry facilities. This paper also discusses specific missions for these devices at the Three Mile Island and Chernobyl nuclear power plant sites at the time of the accidents. Also discussed is the status of devices under development for future applications, as well as research on robotics.

Energy Technology Data Exchange (ETDEWEB)

Scientists at JPL have developed chemical and biological techniques using microspheres filled with drugs, electron-opaque metals, or radioactive, fluorescent, magnetic or electrically charged materials to label specific groups of cells. Synthetic polymeric microspheres are coupled with specific antibodies to form reagents called immunomicrospheres, which can seek out and attach themselves to any specific group of cells. These cell-labeling techniques, therefore, open new avenues not only to the basic study of cells but also to the diagnosis and treatment of many diseases, including cancer.

Energy Technology Data Exchange (ETDEWEB)

This report summarizes evaluations by the National Institute of Standards and Technology (NIST) of Department of Energy (DOE) activities on waste packages designed for containment of radioactive high-level nuclear waste (HLW) for the six month period February 1988 through July 1988. Activities for the DOE Materials Characterization Center are reviewed for the period January 1988 through June 1988. A summary is given of the Yucca Mountain, Nevada disposal site activities. Short discussions relating to the reviewed publications are given and complete reviews and evaluations are included. 20 refs., 1 fig., 1 tab.

Energy Technology Data Exchange (ETDEWEB)

This executive summary presents the motivation, structure, objectives, methodologies and results of the first stage of the international DECOVALEX project - DECOVALEX I (1992-1995). The acronym stands for Development of Coupled Models and their Validation against Experiment in Nuclear Waste Isolation, and the project is an international effort to develop mathematical models, numerical methods and computer codes for coupled thermo-hydro-mechanical processes in fractured rocks and buffer materials for geological isolation of spent nuclear fuel and other radioactive wastes, and validate them against laboratory and field experiments. 24 refs.

Energy Technology Data Exchange (ETDEWEB)

A useful method for preparing radioiodinated photoaffinity labels from alkyl anilines which offer significant advantages over present methods is described. The one-pot synthesis gives good radiochemical yields (40-64%) of pure, high specific activity (350-1500 mCi/{mu}mol) {sup 124}I labelled iodaryl azides while minimising manipulation of radioactive materials. Purification of the ({sup 125}I)iodoazido photoaffinity labels is achieved by high performance liquid chromatography. (author).

International Nuclear Information System (INIS)

Throughout the DOE complex there are numerous facilities that handle hazardous and radioactive waste solutions. Due to the hazardous constituents of the mixed waste, secondary containment of tank systems and their ancillary piping, in accordance with Resource Conservation and Recovery Act, is a concern for such existing facilities. The Idaho Division of Environmental Quality was petitioned in 1990 for an Equivalent Device determination regarding secondary containment of waste lines embedded in interior concrete walls. The petition was granted; however, it expires in 1996. To address the secondary containment issue, additional studies were undertaken. One study verified the hypothesis that an interior wall pipe leak would follow the path of least resistance through the naturally occurring void found below a rigidly supported pipe and pass into an adjacent room where detection could occur, before any significant deterioration ...

Science.gov (United States)

Surgical fires--fires that occur on or in a surgical patient--are a rare but devastating complication of surgical procedures. They can happen during almost any kind of operation and can have dire consequences for both the patient and the hospital. The risk of surgical fires can be minimized as long as everyone on the surgical team understands how fires start and what to do when they occur. It's important to recognize the interaction among ignition sources, oxidizers, and fuels--the three sides of the classic fire triangle. What's more, staff members need to be alert to "hidden" fire risks, such as unsuspected oxygen-enriched atmospheres and less-than-obvious fuels. They also need to be drilled in the correct steps for responding to fires. In this guide, we describe the elements of surgical fires, including the types of equipment and materials that make up each side of the fire triangle. Through a series of case histories, ...

International Nuclear Information System (INIS)

Water chemistry of nuclear power plants has played an important role in reduction of personnel doses, structural materials and fuel integrity assurance, and reduction of radioactive wastes production. Further contributions are requested for advanced utilization of the LWR, advanced fuels and aging management of plants. Since water chemistry has an effect on all structure and materials immersed and at the same time affected by them, the optimum control not sticking to specific issues and covering the whole plant is required for these requests. Taking account of roles and activities of the industry, governmental institutes and academia, road maps on research and development plans for water chemistry were compiled into identified eleven items with targets and counter measures taken, such as common basic technologies, dose reduction, SCC mitigation, fuel cans corrosion/hydrogen absorption mitigation, condition based maintenance ...

Energy Technology Data Exchange (ETDEWEB)

Low level radioactive wastes (concrete pieces) or materials to be melted such as burnt ashes of wastes are charged into a melting furnace. Then, gyrotron of a microwave generator is oscillated, and generated microwaves of a large power are introduced to a melting furnace by a waveguide. The microwaves are irradiated from an irradiator to a beam converging-type reflecting mirror antenna disposed opposite to the irradiator. Then, an antenna driving portion is operated to rotate and move the antenna in parallel. With such procedures, the microwaves of a large power are converged acutely in a beam-like manner to a predetermined range in the melting furnace, and the converged beams of the microwaves are scanned. This can generate heat from the inner side of the materials to be melted charged to the melting furnace by the induction loss and they are melted. (I.N.)

Energy Technology Data Exchange (ETDEWEB)

Possible accident scenarios for a fusion reactor include breaches in the vacuum or cooling system. Intruding air or steam could react with structural or plasma facing materials, possibly mobilizing radioactive isotopes. Safety assessments must consider the early dose at the site boundary from the release of these activated materials. Previous calculations have indicated that cobalt isotopes dominate dose calculations for designs using stainless steel. Values used in these calculations, however, had been largely determined by the measurement limits of the chemical analysis methodology instead of measured releases. The purpose of the current study was to refine the analytical method to reduce the limit for detecting cobalt, and then test PCA steel in air and steam between 973 and 1473 K. Goals were to obtain more accurate measurements of cobalt mobilization in terms of g/m{sup 2}{center_dot}h and insight into the mobilization ...

International Nuclear Information System (INIS)

The principal types of corrosion are presented which can occur in CANDU steam generator. There are also presented the operation conditions, the specifications referring to the water chemistry and the construction materials of Steam Generator, the factors that have a great influence on the corrosion behaviour during the whole exploitation period of this equipment. The most important elements of CANDU Steam Generator ageing management program are also discussed. (R. P.)

Science.gov (United States)

The phytomanagement of Se-polluted soil and water is one strategy that may be environmentally sustainable and cost-effective for soils and waters enriched with natural-occurring Se. Several plant species, including Indian mustard (Brassica juncea), pickleweed (Salicornia bigelovii), and other salt/S...

Energy Technology Data Exchange (ETDEWEB)

Carbide reactions occurring in a precipitation-hardening gamma/gamma-prime Ni-Cr alloy during prolonged high-temperature aging are investigated experimentally. It is found that the decomposition of primary MC carbides, which is accompanied by the precipitation of M23C6 particles, may lead to void nucleation and growth. The effect of carbide transformations on the residual properties of the material at temperatures above the equicohesion temperature is observed at the late stages of aging only. 6 references.

International Nuclear Information System (INIS)

In the safety assessment of a high-level radioactive waste (HLW) disposal system, it is required to estimate radiological impacts on future human beings arising from potential radionuclide releases from a deep repository into the surface environment. In order to estimate the impacts, a biosphere model is developed by reasonably assuming radionuclide migration processes in the surface environment and relevant human lifestyles. Releases from the repository might not occur for many thousands of years after disposal. Over such timescales, it is anticipated that the considerable climatic change, for example, induced by the next glaciation period expected to occur in around ten thousand years from now, will have a significant influence on the near surface environment and associated human lifestyles. In case of taking these evolution effects into account in modeling, it is reasonable to develop several alternative models on ...

International Nuclear Information System (INIS)

Neutron radiography (NR) is a useful non-destructive method for determination of hydrogen content in various building and technical materials. Monitoring of transport processes of moisture and hydrogenous liquids in porous building materials is enabled by fast, quasi-real-time NR methods based on novel imaging plate neutron detectors (IP-NDs). Hydrogen content in the samples is determined by quantitative analysis of measured profiles of neutron attenuation in the samples. Detailed description of quantitative NR method is presented by the authors in another accompanying contribution at this conference. Deterioration of building materials is originated by different processes that all require presence of water therefore it is essential to limit or prevent the transport of water through the porous material. In this presentation, results of a study of clay brick impregnation by silicone based hydrophobic ...

Energy Technology Data Exchange (ETDEWEB)

The national remediation program in Croatia consists of three stages: (1) identification and characterization of radioactively contaminated sites; (2) preparing activities for restoration; and (3) physical restoration at selected (high-prioritized) sites. The program is coordinated by the APO and, in the first stage, performed by both national research institutes of Ruder Boskovi and Institute for Medical Research and Occupational Health. The program supervisors are Ministry of Health, Ministry of Economy (Department of Energy) and State Administration for Environmental Protection. There were more than thirty sites suspected to be radioactively contaminated in Croatia. They were classified into four contamination type groups: (1) dumps containing contaminated coal slag and ash; (2) dumps containing contaminated phosphates and phospho-gypsum resulting from fertilizers industry; (3) geothermal springs and gas/oil wells; and (4) sites containing ...

Energy Technology Data Exchange (ETDEWEB)

The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects are calculated, with reference to ITER/NET (International ...

Energy Technology Data Exchange (ETDEWEB)

Gamma scanning measurements are used to determine the radioactive nuclides from an irradiated fuel rod in a hot cell which is a routine task in the Irradiated Materials Examination Facility (IMEF) of the Korea Atomic Energy Research Institute (KAERI), Total gamma spectra of radioactive nuclides and the atomic ratio of {sup 134}Cs to {sup 137}Cs in a few segments of a single fuel rod are measured by the present gamma scanning system. For the purpose of determining the radioactive nuclide's distribution in detail within a fuel rod quantitatively, we attempt to upgrade the present gamma scanning system in this paper, therefore, an investigation of the feasibility of the tomographic gamma scanning (TGS) technique, which is one of the promising nondestructive assay (NDA) methods is proposed. The TGS technique is an efficient method and it has an accurate precision for the characterization of several ...

International Science & Technology Center (ISTC)

Production of Radioactive Isotopes in Republic of Kasakhstan.

Energy Technology Data Exchange (ETDEWEB)

Dissimilar metal welds between ferritic low-alloy and austenitic stainless steels commonly occur in power plant application. In order to overcome some of the problems encountered here, a trimetallic configuration using an intermediate piece (such as Alloy 800) between the austenitic and ferritic steels has been suggested. This paper describes some features of the joints between modified 9Cr-1Mo steel and Alloy 800, produced with Inconel 82/182 filler material. The joints require heat-treatment after welding and the results have shown that a treatment at 760 C for 2 h would be optimal. Although most tensile failures occurred in the weld metal the welds were found to exhibit strength properties that are at least equal to those of Alloy 800, with a tensile elongation lying between those of the two base materials. Similarly, while the weld metals are slightly less tough than the two base ...

International Nuclear Information System (INIS)

Wind tunnel tests were performed of three fugitive dust control agents derived from potato and sugar beet products. These materials are being considered for use as dust suppressants to reduce the potential for transport of radioactive materials by wind from radioactive waste construction and remediation sites. Soil and dust control agent type, solution concentrations, application quantities, aging (or drying) conditions, surface disturbance, and wind and saltating sand eolian erosive stresses were selected and controlled to simulate application and exposure of excavated soil surfaces in the field. A description of the tests, results, conclusions, and recommendations are presented in this report. The results of this study indicate that all three dust control agents can protect exposed soil surfaces from extreme eolian stresses. It is also clear that the interaction and performance of each agent with ...

British Library Electronic Table of Contents (United Kingdom)

The erosion of rocks rich in organic matter typically leads to the complete mineralization of the organic material. However, in some cases, it is re-deposited to become a part of sediments once more. This process should be considered to be a part of global carbon cycle, possibly much more significant than assumed to-date. The research presented here aims to characterize re-worked organic matter occurring in post-glacial sediments of southern part of Poland, in the Oder river valley (the Racib?rz town region, Miocene, Pleistocene and Holocene age). Organic substances extracted from the sediments originated from organic matter that had resided in rocks eroded by glaciers. Sediments were sampled in two boreholes which sediments were correlated. Sediments were extracted and extracts analyzed w...

International Nuclear Information System (INIS)

We obtained the ratios of "1"3"4Cs/"1"3"7Cs and "1"5"4Eu/"1"3"7Cs in spent PWR fuels with gamma scanning equipment of irradiated material examination facility. The fuel segments, of which the burn-up is about 40 GWD/MTU and its cooling time is 8.4 years, are prepared in Post Irradiated Examination Facility and transported to IMEF. By considering of multi-peaks of "1"3"4Cs and "1"5"4Eu, we obtained the relative efficiency of the gamma scanning system as a function of energy. And finally we obtained the number ratios of radioactive nuclides in 72 fuel pellets, radioactive "1"3"4Cs/"1"3"7Cs and "1"5"4Eu/"1"3"7Cs. (author). 4 refs., 27 tabs., 28 figs.

Energy Technology Data Exchange (ETDEWEB)

The document describes the outcome of the CSN/CIEMAT-00 interlaboratory test comparison among environmental radioactivity laboratories. the exercise was organised according to the ISO-43 and the ISO/IUPAC/AOAC Harmonized Protocol for the proficiency testing of analytical laboratories. the test sample was a soil containing environmental levels of K-40, Ra-226, Ac-228, Sr-90, Cs-137, Cs-134, Pu (239-240) y Am-241. the Universidad Autonoma de Barcelona prepared the material and reported adequate statistical studies of homogeneity. The results of the exercise were computed for 30 participating laboratories, and their analytical performance was assessed using the u-score approach. A raised percentage of satisfactory laboratory performance has been obtained for all the analysis, being the best performance in gamma measurements. The exercise has drawn that several laboratories have difficulties in the evaluation of combined uncertainty, mainly in ...

International Nuclear Information System (INIS)

Technical developments in the construction of high power accelerators have created new research activities on accelerator-driven transmutation technologies (ADTT) with main applications for energy production and nuclear waste transmutation. The on-going research was reported and discussed at the conference. The studies of energy production based on ADTT indicate possible important advantages compared to the present nuclear power reactors. Natural Uranium or Thorium is burned in a subcritical reactor with or without simultaneous incineration and transmutation of nuclear waste. High level radioactive wastes and weapons Plutonium constitute an environmental and proliferation problem. Studies were reported on the possibilities to use ADTT to considerably shorten the life-time and reduce the amount of long-lived radioactive waste in order to decrease the volumes needed for long-term geologic deposition. A panel discussed the ADTT impact on nuclear ...

International Nuclear Information System (INIS)

Type 304 stainless steels (solution annealed material, cold worked material and fine grain material) were neutron irradiated to 3 x 10"2"5n/m"2 at 290degC and at 50degC. Each specimen was examined by SSRT test in high temperature water with 8 ppm dissolved oxygen and Ar gas environments. Results were as follows: (1) IASCC susceptibility of each material can be classified by 0.2% proof stress (PS) obtained from SSRT test in Ar gas: No IASCC susceptibility was observed in the PS range 850 MPa. (2) The uniform elongation (UE) in Ar gas environment decreased with increasing PS up to 800 MPa, and became about 0% in the PS range >800 MPa. (3) It was suggested that IASCC did not occur even if material had IASCC susceptibility, when under a condition that brittle fracture mechanism controls a specimen failure. (author)

International Nuclear Information System (INIS)

In an HTR plant high temperature components of Alloy 800 materials are subjected to temperatures from about 550 to 850degC in the long term; higher temperatures may occur in the short term. Thus the creep and stress-rupture parameters govern the design of these components. Since in recent years the scope of experimental data available for Alloy 800 materials has considerably increased, a new evaluation of the creep and creep-rupture properties was performed using a data bank computer. The relationships between the characteristics of the creep and creep-rupture behaviour and the metallurgical parameters were investigated by multilinear regression analyses. On the basis of the results of these analyses and after discussion in material expert committees new material specifications were determined for different types of Alloy 800. They were included into the draft standards DIN 17459 ...

Science.gov (United States)

Environmental characteristics of conceptual fusion-reactor systems based on magnetic confinement are examined quantitatively, and some comparisons with fission systems are made. Fusion, like all other energy sources, will not be completely free of environmental liabilities, but the most obvious of these-- tritium leakage and activation of structural materials by neutron bombardment-- are susceptible to significant reduction by ingenuity in choice of materials and design. Large fusion reactors can probably be designed so that worst-case releases of radioactivity owing to accident or sabotage would produce no prompt fatalities in the public. A world energy economy relying heavily on fusion could make heavy demands on scarce nonfuel materials, a topic deserving further attention. Fusion's potential environmental advantages are not entirely ...

Energy Technology Data Exchange (ETDEWEB)

A series of experiments involving high explosives and radioactive materials were conducted at Los Alamos, New Mexico, primarily to understand certain safety aspects of operational nuclear weapons. The experiments were conducted underground in large diameter holes as deep as 120 ft. The location was selected because it had geologic and hydrologic characteristics that assured complete containment of the experiments and precluded any possible contamination of groundwater. Important features verified by the USGS included the absence of any recharge and about 1200 feet of dry rock above the groundwater aquifer. Residual materials dispersed by detonation of the high explosives remain at the bottom of the experimental holes. The materials of significance from an environmental standpoint include about 40 kg of plutonium, 93 kg of enriched uranium, at least 82 kg of depleted uranium, 13 kg of beryllium, and an ...

International Nuclear Information System (INIS)

Determination of americium (Am) is one of the requirements of chemical quality assurance of plutonium (Pu) bearing fuel materials. Though many methods are published for determining Am at picogram to femtogram levels in environmental and biological matrices, yet a few of them are used routinely for Pu based nuclear fuel samples. This paper gives a brief summary of the different analytical methods available and presents results of our experiments on the determination of Am in Pu bearing fuels using gamma spectroscopy. The methods utilizing gamma emissions from "2"4"1Am and Pu isotopes are fast as they do not involve chemical separation of Pu and Am, do not require an accurate knowledge of the efficiency values of the detector systems and are not dependent on the availability of a radiometric standard for "2"4"1Am. In addition, for aged Pu samples containing large amounts of "2"4"1Am, there is no need for dilution and this reduces the volume of analytical ...

Energy Technology Data Exchange (ETDEWEB)

The design of high level radioactive waste (HLW) repositories in deep geological media in which bentonite clay is proposed as a sealing material leads to the need of further studying the behaviour of highly compacted expansive soils when subjected to mechanical, hydraulic and thermal changes. Laboratory tests may help to understand the processes that take place in the clay barrier under simple and controlled conditions and to develop the governing equations. The laboratory tests enable to isolate the different processes, making their interpretation easier, and provide with fundamental data concerning the parameters to be used in the models. The extremely low permeability of these materials, their avidity for water (high suction) and their high swelling capacity make necessary the modification of the conventional laboratory techniques and procedures to determine basic physical parameters. The main hydraulic properties of the ...

International Nuclear Information System (INIS)

Full text: There have been many recent calls for increased international cooperation in the field of nuclear forensics. While much is already being done, for example by the International Technical Working Group on Nuclear Smuggling and International Atomic Energy Agency, more effort is needed as cooperation on real-world incidents is often ad hoc. As a result, incidents - particularly diversions of nuclear material - are not effectively investigated, and opportunities to keep dangerous materials out of the hands of terrorists or proliferators are missed. Forensics techniques can be used to investigate many types of incidents involving illicit uses of nuclear or radiological material, but the need for cooperation can be seen most clearly in the area of illicit trafficking where collaboration is needed now. Here governments have had some success interdicting smuggled material but diversions are not ...

Energy Technology Data Exchange (ETDEWEB)

The security of ports and transportation is of utmost importance for the development of economy and the security of a nation. Among the necessary actions to ensure the security of ports and borders, the inspection of containers is one of the most time consuming and expensive procedures. Potential threats are the illegal traffic of radioactive materials that could be employed for the construction of weapons, as uranium and plutonium. New techniques for the inspections of containers should be fast, allow the detection and identification of dangerous materials, and be non-invasive, to reduce costs and delays. We propose to build a large surface photon and neutron detector based on plastic scintillator to identify the presence of fissile or fertile material inside a container. The detector consists of scintillator bars, wrapped in thin foils of reflecting material containing gadolinium ...

Energy Technology Data Exchange (ETDEWEB)

The WAND (Waste Assay for Nonradioactive Disposal) system can scan thought-to-be-clean, low-density waste (mostly paper and plastics) to determine whether the levels of any contaminant radioactivity are low enough to justify their disposal in normal public landfills or similar facilities. Such a screening would allow probably at least half of the large volume of low-density waste now buried at high cost in LANL`s Rad Waste Landfill (Area G at Technical Area 54) to be disposed of elsewhere at a much lower cost. The WAND System consists of a well-shielded bank of six 5-in.-diam. phoswich scintillation detectors; a mechanical conveyor system that carries a 12-in.-wide layer of either shredded material or packets of paper sheets beneath the bank of detectors; the electronics needed to process the outputs of the detectors; and a small computer to control the whole system and to perform the data analysis. WAND system minimum detectable activities ...

Energy Technology Data Exchange (ETDEWEB)

During rolling contact fatigue of the inner rings of ball bearings three stages of material response can be distinguished, in terms of the volume that is plastically deformed upon overrolling. After a first stage of material strengthening during which a decrease occurs for the volume that is deformed plastically, an effectively stationary, second stage is entered which is eventually succeeded by a third stage exhibiting a pronounced increase of the volume that is deformed plastically upon overrolling, which leads to failure. It is suggested that carbon diffusion induced by local temperature peaks occurring at the moment of overrolling is the key mechanism leading to fatigue damage. The amount of decomposed retained austenite is a useful, practical parameter to assess fatigue life. It is shown that published ideas about the role of certain components of residual stress in enhancing fatigue life are not ...

International Nuclear Information System (INIS)

Bituminization has to be selected as the process for conditioning radioactive liquid wastes arising from the two VVER V-230 reactors being built at Temelin in the Czech Republic. In the process, a thin-film evaporator, operating at a waste-product temperature of 160"oC, evaporates all free water from the waste effluents. Remaining solids are homogeneously dispersed in a bitumen matrix which solidifies through natural cooling of the binder. The relative simplicity of the process reduces construction costs for on-line waste facilities and operating costs are less given the cheap basic material and simple maintenance. The reliability of the process has been demonstrated at Western reactors and reprocessing plants though adaptations have had to be made to accept VVER effluents. (UK).

British Library Electronic Table of Contents (United Kingdom)

Polymer insulating materials used in radioactive environments are subjected to a risk of surface degradation caused by tracking. The tracking behavior becomes more complex with the presence of magnetic field. This paper presents investigation of tracking failure of gamma-ray irradiated polybutylene naphthalate (PBN) and polybutylene terephthalate (PBT) under magnetic field. The samples were irradiated in air up to 100 kGy and then up to 1000 kGy with dose rate of 10 kGy/h by using a 60Co gamma-source. Magnetic field Formula Not Shown with flux density of 250 mT was assembled perpendicularly to electric field Formula Not Shown , which gave rise to relative angle between Formula Not Shown and surface normal vector Formula Not Shown of 0degree, 90degree and 180degree, respectively. The experi...

International Nuclear Information System (INIS)

The transport of air pollutants in coastal regions has been known to be strongly affected by the mesoscale atmospheric circulations such as sea-land breezes. These mesoscale atmospheric circulations depend on synoptic weather conditions. In this study, a three-dimensional sea-land breeze model was developed to evaluate the effects of the sea and land breezes on the atmospheric dispersion of radioactive materials released from nuclear power plants in Korea. In the model, the hydrostatic primitive equations in the terrain-following coordinate system were used. The mesoscale atmospheric circulation simulation were carried out under various synoptic weather conditions for all seasons around the Wolsung nuclear power plant site.

International Nuclear Information System (INIS)

Corrosion is a materials degradation process that engineering personnel in the pulp and paper industry have had to accept as unavoidable to some degree, due to aggressive processing conditions prevalent in paper mills. The increasing incidence of corrosion-related failures in plant and equipment has resulted in the introduction of new techniques to monitor corrosion rates, since many of the more traditional methods do not provide data that is either recent or accurate enough. Thin layer activation (TLA) is a new corrosion monitoring technique which has recently been employed to measure corrosion trends inside a continuous pulp digester. With TLA a surface is irradiated by a particle beam from a nuclear accelerator, causing it to be labelled with an accurate depth profile and low level radioactivity. By monitoring this activity, it is possible to calculate how much of the surface has been removed by corrosion. 14 refs., 7 figs., 4 tabs.

Energy Technology Data Exchange (ETDEWEB)

Surveillance and maintenance (S M) of 75 sites were conductd by the Remedial Action Section for the Environmental Restoration Program for surplus facilities and sites contaminated with radioactive materials and/or hazardous chemicals. S M activities on these sites were conducted from the end of their operating life until final facility disposal or site stabilization. The objectives of the Waste Area Grouping S M Program are met by maintaining a program of routine S M as well as by implementing interim corrective maintenance when deemed necessary as a result of site surveillance. This report briefly presents this program's activities and includes tables indicating tank levels and dry well data for FY 1991.

International Nuclear Information System (INIS)

Korea Atomic Energy Research Institute (KAERI) has many R and D facilities in operation, including HANARO research reactor, radioactive waste treatment facility (RWTF), post-irradiation examination facility (PIEF) and irradiated material test facility (IMEF). Recently, nation-wide interest is focused on the safety and security of major industrial facilities. Safe operation of nuclear facilities is imperative because of the consequence of public disaster by radiological release/ contamination, in case of an accident. Recently, Ministry of Science and Technology (MOST) of the Korean government announced amendments of Atomic Energy laws to enforce requirements of the physical protection and radiological emergency. In this paper, the context of amended Atomic Energy laws were reviewed to confirm quality assurance measures and identify additional QA activities, if any, that is required by the amendment

International Nuclear Information System (INIS)

By the department Radio-ecology of the Laboratory for Radiation Research, in the period 1981 up to 1989 inclusive, the transfer has been studied, from soil to plant, of a number of important activation and fission products, originating in the nuclear-power production in nuclear power plants. The purpose of this study was twofold: on the one side the quantification of this transfer for various agrarian systems and on the other side to find out in how far, after an accidental contamination, certain agriculture activities can influence essentially the transfer and subsequently the radiation burden for the population. Emphasis lay, the last years, in particular upon this second aspect. The results of this study form essential basic data for diffusion models for radioactive materials which, in turn, are important in estimating the effects of measures. (author). 6 refs.; 4 figs.

Energy Technology Data Exchange (ETDEWEB)

Sheltering, evacuation and distribution of stable iodine tablets are considered to be major early emergency actions aiming at diminishing the consequences after a release of radioactive materials from nuclear power plants into the air. Whether in real situations emergency managers will act accordingly is hard to predict. Uncertainties associated with these decisions are termed 'volitional' uncertainties. These uncertainties, however, cannot be assessed by expert judgements as they express the decision at stake in an emergency situation. Uncertainties on the times to implement countermeasures and on the times for the general population to respond to these measures can be assessed by experts, as they represent 'lack-of-knowledge' uncertainties. This paper describes the difference in approach of both types of uncertainties and shows the results of expert judgements on the latter type of uncertainties in early ...

Energy Technology Data Exchange (ETDEWEB)

Radon proof barriers are used for lowering of radon transport from the soil into the house and the determination of the radon diffusion coefficient is an important parameter to be determined in order to design the minimal thickness of the radon proof insulation. A method has been developed in our laboratory by using modified Lucas cells connected to a radon source and tightly closed onto the top by the tested membranes whose radon diffusion coefficients are being measured. Solving the time-dependent differential equation for radon diffusion in the membrane for well-defined experimental conditions the effective radon diffusion coefficient of the insulating material can be evaluated by comparing the radon concentration decrease in the cell for the first hours with the well-known radioactive decay. First results obtained in several preliminary tests carried out with a parafilm M barrier and two polyethylene membranes are shown in this paper.

Energy Technology Data Exchange (ETDEWEB)

We have conducted an investigation to determine the occurrence and distribution of erionite, a potential carcinogen, at Yucca Mountain, Nevada. Using x-ray powder diffraction techniques yielding detection limits to below 0.05 wt %, we positively identified erionite in only 3 out of 76 bulk and 12 fracture samples investigated. The three erionite-bearing samples (J12-620/630, UE-25aNo.1-1296.2, and USW G4-1314) all occur above the static water level in clay/zeolite-rich horizons near the top of vitrophyres. Erionite occurs as trace amounts of less than 1 wt % in the whole rock, although it may occur locally in significant amounts as fracture fillings (e.g., UE-25aNo.1-1296.2 where it comprises approximately 45 wt % of the fracture filling material). All three occurrences appear to be extremely isolated cases since erionite was not detected in neighboring samples. Erionite at Yucca Mountain apparently ...

Energy Technology Data Exchange (ETDEWEB)

A prototype hydride storage bed, using LaNi{sub 4.25}Al{sub 0.75} as the storage material, was fitted with strain gages to measure strains occurring in the stainless steel bed vessel caused by expansion of the storage powder upon uptake of hydrogen. The strain remained low in the bed as hydrogen was added, up to a bed loading of about 0.5 hydrogen to metal atom ratio (H/M). The strain then increased with increasing hydrogen loading ({approximately} 0.8 H/M). Different locations exhibited greatly different levels of maximum strain. In no case was the design stress of the vessel exceeded.

Energy Technology Data Exchange (ETDEWEB)

The operation of buildings can be temporarily modified to use much less electricity. These actions may be necessary during regional electricity shortages lasting anywhere from days to months. The electricity conservation measures typically involve a combination of technical modifications, temporary changes in occupant behavior, and greatly increased vigilance. At the same time, attempts to drastically reduce a building's electricity use may have unexpected consequences affecting energy use, the indoor environment, and the performance of building materials and equipment. Electricity shortfalls such as those described in this paper may occur more often as a result of climate change and liberalized electricity markets. (author)

Energy Technology Data Exchange (ETDEWEB)

Directionally solidified nickel-based superalloy DZ4 is an important structural material. However, the grinding burn occurs in grinding processes has hindered the grinding efficiency and dimensional accuracy. This paper investigates the grinding mechanism of this new type of superalloy based on the systematical analyses of variable characteristics of the grinding force, grinding temperature, topography of ground surface, hardness distribution of surface layer, as well as morphology of surface layer from a metallographical point of view. The results will be beneficial to grinding the superalloy with high efficiency and high precision. (orig.)

International Nuclear Information System (INIS)

Nonparabolicity of the heavy hole band in diamond-like semiconductors, which occurs within the framework of the three band model with the perturbation from the other bands taken into account according to the Loewdin procedure, is studied. A direct dependence of nonparabolicity on the band anisotropy (caused by the different effect of Gamma/sub 15c/ and Gamma/sub 12c/ bands) and the inverse dependence on the magnitude of the spin-orbit splittiing is established. A connection between the effective mass of heavy holes and their energy is obtained, which is valid for the majority of diamond-like semiconductors, except for materials with a very strong nonparabolicity of the band of silicon type.

International Nuclear Information System (INIS)

Although there is service experience of Alloy 800 as tubing for superheaters in conventional and nuclear (HTR) power stations and in PWR heat exchangers, there is no corresponding service experience in sodium-cooled fast reactor steam generators. However, some limited experimental studies have been made of corrosion behaviour, and of possible structure modifications and effects on mechanical properties which occur during exposure of this material to a high temperature sodium environment, and these are summarised in the paper. It is concluded that further work needs to be done before Alloy 800 can be confidently endorsed for use as tubing in fast reactor steam generators. (author).

Energy Technology Data Exchange (ETDEWEB)

This report provides a chronological history of policies and practices relating to the management of radioactive waste for which the US Atomic Energy Commission and its successor agencies, the Energy Research and Development Administration and the Department of Energy, have been responsible since the enactment of the Atomic Energy Act in 1946. The defense programs and capabilities that the Commission inherited in 1947 are briefly described. The Commission undertook a dramatic expansion nationwide of its physical facilities and program capabilities over the five years beginning in 1947. While the nuclear defense activities continued to be a major portion of the Atomic Energy Commission`s program, there was added in 1955 the Atoms for Peace program that spawned a multiplicity of peaceful use applications for nuclear energy, e.g., the civilian nuclear power program and its associated nuclear fuel cycle; a variety of industrial applications; and medical research, ...

Energy Technology Data Exchange (ETDEWEB)

Based on the CFD-code FLUENT trademark, theoretical studies were conducted of the influences of incineration chamber geometry (direct, countercurrent and center flow) on the combustion process. The boundary conditions, e.g., the thermal input and the waste grate, were kept constant. Close attention was paid to the distribution of flow, spe-cies, and temperatures. In addition, the influence of a dis-placement body at the end of the combustion chamber was tested. The variation of different wall materials and the prediction of problem areas concerning corrosion, slagging, and contamination completed the studies. Close to the chamber walls, high CO-concentrations may indi-cate corrosion; particle flow may indicate where contami-nation, slagging or erosion could occur. (orig.)

International Nuclear Information System (INIS)

The synthesis of dense sintered sialon with external additives selected from the system Y_2O_3-AlN-SiO_2 is reported. The highest density (3.21 g/cm"3) was achieved at 1750 degrees C at 90 min of sintering with 5 wt% additive. The degree of sialon substitution increased with the amount of liquid; the YSiO_2N crystalline phase formed concurrently. Strength degradation occurred above 1000 degrees C. The fracture toughness of the material sintered with a lower amount of sintering aid remained relatively unchanged to 1200 degrees C. The material with more additive exhibited decreased toughness above 1000 degrees C.

British Library Electronic Table of Contents (United Kingdom)

Porous flow occurs in a wide range of materials and applies to many commercially relevant applications such as oil recovery, chemical reactors and contaminant transport in soils. Typically, breakthrough and pressure curves of column floods are used in the laboratory characterization of these materials. These characterization methods lack the detail to easily and unambiguously resolve flow mechanisms with similar effects at the core scale that can dominate at the aquifer or oil field scale, as well as the effects of geometry that control the flow at interfaces as in a perforated well or the inlet of an improperly designed column. Non-invasive imaging techniques such as MRI have been shown to provide a far more detailed characterization of the properties of the solid matrix and flow, but usu...

International Nuclear Information System (INIS)

Increasing threat by terrorists for a possible nuclear attack is particularly alarming in recent years. The likelihood of such an event is highly uncertain but cannot be ruled out. The consequence of such an event would be highly disastrous and the implications could be far-reaching both socially and politically. It is feared that significant amount of nuclear weapons materials may be kept under poor security. Therefore, there is a greater demand with utmost priority to curb nuclear terrorism by adapting proper security measures. One of the most important measures is to stop illicit trafficking of nuclear materials which are the source of building nuclear explosive devices. According to the IAEA illicit trafficking database (ITDB) report, a total number of 252 incidents were reported in 2006, of which 150 occurred in 2006 and the remaining 102 had taken place prior to that year, mainly in 2005

British Library Electronic Table of Contents (United Kingdom)

The static corrosion tests in lead-bismuth eutectic (LBE) were conducted from 450degreeC to 600degreeC to understand corrosion behavior and develop corrosion resistant materials for heavy liquid metal systems. While increase of Cr content in steels enhances corrosion resistance in LBE, the effect approaches a constant value above 12wt% of Cr. Corrosion depth in LBE increases with increasing temperature and corrosion attack becomes severe above 550degreeC even under the condition of high oxygen concentration. Nickel dissolution and Pb-Bi penetration occur in 316SS and JPCA above 550degreeC under the condition of high oxygen concentration. When oxygen concentration decreases below the level of Fe oxide formation, corrosion attack on these steels also becomes violent due to dissolution of var...

International Nuclear Information System (INIS)

Composite nitrides (such as BN, TiN) are widely used in various industrial applications because of their extreme wear and corrosion resistance, thermal and electrical properties. in order to obtain composite materials with these optimal properties, it is important to elucidate whether any chemical reactions occur at nitride/metal interfaces, e.g., those involving BN-Ti/TiN. Materials of interest include the deposition by PVD of Ti and TiN on BN substrates. Some of these systems were then subjected to varying degrees of physical and thermal alteration. Detailed X-ray photoelectron spectroscopy (XPS) has therefore been rendered of these interfaces using cross-sectional display and sputter etching. Resulting structural and morphological features have been investigated with transmission electron microscopy (TEM) and X-ray diffraction (XRD). Diffusion of the nitridation, oxynitride formation and interfacial growth are of general ...

International Nuclear Information System (INIS)

Research is in progress to obtain a satisfactory creep ductility for alloy 800 when used as heat exchanger material in sodium-cooled fast reactors (LMFBR). The creep test characteristics at present available show that a pronounced tendency to reduced elongation by creep failure may arise after prolonged testing in the 500-700 deg C temperature range. This phenomenon is now agreed to be primarily inherent to the conditions for Ni_3(Ti,Al) precipitation in the material and hence to the Ti and Al concentrations. By structural studies and hardness measurements on material subjected to creep tests and taken from a large number of castings, the relationship was established between the (Ti+Al) content and the structural hardness effect of Ni_3(Ti,Al) at 600 deg C. Below a certain Ti+Al concentration, no precipitation occurs and hence the creep ductility to failure can be improved considerably by limiting the ...

Energy Technology Data Exchange (ETDEWEB)

Preliminary results are presented from a field study to evaluate the relative hydrologic performance of various landfill capping technologies installed by the Los Alamos National Laboratory at Hill Air Force Base, Utah. Four cover designs (two Los Alamos capillary barrier designs, one modified EPA RCRA design, and one conventional design) were installed in large lysimeters instrumented to monitor the fate of natural precipitation between 01 January 1990 and 20 September 1993. After 45 months of study, results showed that the cover designs containing barrier layers were effective in reducing deep percolation as compared to a simple soil cap design. The RCRA cover, incorporating a clay hydraulic barrier, was the most effective of all cover designs in controlling percolation but was not 100% effective. Over 90% of all percolation and barrier lateral flow occurred during the months of February through May of each year, primarily as a result of snow melt, early spring ...

International Nuclear Information System (INIS)

Radon concentration measurements were carried out using solid-state nuclear track-etch detectors (SSNTDs) type CA 80-15 cellulose nitrate films, in a Pleistocenic cave at Petralona, in Halkidiki, Northern Greece, at 55 km from the city of Thessaloniki. Radon levels as high as 88 kBqxm"-"3 (2.38 nCi x l"-"1) have been recorded inside the cave equivalent to 11.90 WL in terms of occupational exposure to radon and its decay products. Absorbed dose rates were performed using TL dosimeters, type TLD-200 (CaF_2-Dy) in a continuous monitoring program (integrated measurements). Dose rate levels as high as 110 nGy x h"-"1 were recorded inside the cave. In interpreting the high levels of radiation doses, radioactivity measurements regarding the naturally occurring "2"3"8U, "2"3"2Th and "4"0K radionuclides were carried out in various speleothems found at different sites in the cave. (author)

Energy Technology Data Exchange (ETDEWEB)

In isolated rat adipocytes, insulin inhibits lipolysis to a greater extent than would be predicted by the decrease in (-/+)cAMP activity ratio of cAMP-dependent protein kinase (A-kinase), from which it was speculated that insulin promotes the dephosphorylation of hormone-sensitive lipase. They have examined the phosphorylation state of cellular proteins under conditions of varying A-kinase activities in the presence and absence of insulin. Protein phosphorylation was determined by SDS-PAGE electrophoresis of extracts from /sup 32/P-loaded cells; glycerol and A-kinase activity ratios were measured in the cytosolic extracts from control, non-radioactive cells. Increased protein phosphorylation in general occurred over the same range of A-kinase activity ratios, 0.1-0.3, associated with increased glycerol release. The insulin-induced decrease in lipolysis was associated with a decrease in the /sup 32/P content of several proteins, an effect not ...

Energy Technology Data Exchange (ETDEWEB)

Trace elements, including manganese may afford protection from deleterious effects of aflatoxin. Young male Fischer rats received ip injections of aflatoxin B1 (AFB1) in dimethyl sulfoxide (DMSO), 1 mg/kg, 2 mg/kg or 4 mg/kg. Control groups received DMSO ip or no injection. All animals were intubated with 3 microCi of (/sup 54/Mn)-MnCl/sub 2/ 12 hr post-injection. Sacrifice occurred 72 hr after gavage of the radiolabel. All tested levels of AFB1 affected the loss of total body radioactivity. This response was observed within 12 hr when toxin-treated groups excreted almost 4 times more counts than controls. From 12-36 hr following radiolabel administration, AFB1 appeared to enhance excretion; by 72 hr, toxin-treated animals (especially those receiving higher doses) appeared to conserve the metal. Aflatoxicosis manifested itself through reduced body weight gain. The data provide support evidence that Mn and AFB1 biointeract.

International Nuclear Information System (INIS)

In order to qualify corrosion resistant materials for high level waste (HLW) packagings acting as a long-term barrier in a rock salt repository, the corrosion behaviour of the preselected materials Ti 99.8-Pd, Hastelloy C4 and two unalloyed steels was investigated. The resistance of the materials to general corrosion, local corrosion and stress corrosion cracking was examined under postulated accident conditions in the repository by long-term immersion tests of up to 4 years duration and electrochemical methods. The parameters investigated were different salt brines, temperatures of 90 deg. C, 170 deg. C and 200 deg. C as well as a gamma radiation field of 10"3Gy/h (10"5rad/h). Among the materials studied, Ti 99.8-Pd exhibited the highest corrosion resistance. This material corroded at a very low rate (

Science.gov (United States)

Structural complexities reduce the homogeneity necessary for a site characterization model to an unacceptable level for performance assessment for radioactive waste disposal sites. The proposed site lies between the northern, stable Diablo platform and the southern, mobile Mesozoic Chihuahua tectonic belt. Structural movement along this interface has been active for the past 14,000 years. In addition, the area lies along the northern margin of the Permian Marfa basin and the northeastern margin of the deeply faulted Hueco bolson segment of the late Cenozoic Rio Grande rift system. Recent seismic activity with extensive surface rupture in Quitman Canyon (30 mi southeast of the site) is also documented from the 1931 Valentine, Texas, earthquake (6.4 Richter scale). The site is underlain by either a thrust fault or the complex terminus of a Mesozoic thrust fault. This fault is a segment of the continuous thrust sheet extending from exposures in the Sierra Blanc area, ...

International Nuclear Information System (INIS)

Borosilicate based glass formulations have been found suitable for fixing the HLW (high level radioactive liquid waste) generated after reprocessing of the spent nuclear fuel. As the glass experiences continuous irradiation by #alpha#, #beta#a, and #gamma# radiations from the radioactive components of HLW, alteration in the glass structure may occur. Understanding of these structural evolutions of the nuclear waste glasses under irradiation is crucial to secure long term disposal and predict their behavior. In the present work, alkali based barium borosilicate glasses, having composition similar to that of Trombay Research Reactor waste glass were irradiated with high energy "1"2C beam and the radiation induced changes were monitored by micro Raman experiment. Since a "1"2C atom can be considered as a cluster of alphas, this beam was chosen to yield linear energy losses (LET) comparable to that in case of a particles. The ...

Energy Technology Data Exchange (ETDEWEB)

Corrosion is a primary determinant of waste package performance at the proposed Yucca Mountain Repository and will control the delay time for radionuclide transport from the waste package. Corrosion is the most probable and most likely degradation process that will determine when packages will be penetrated and the shape, size, and distribution of those penetrations. The general issues in corrosion science, materials science and electrochemistry are well defined, and the knowledge base is substantial for understanding corrosion processes. In this paper, the Yucca Mountain Repository is viewed from a corrosion perspective. A major component of the long-term strategy for safe disposal of nuclear waste at the Yucca Mountain Repository is first to completely isolate the radionuclides in the waste packages for long times and to greatly retard the egress and transport of radionuclides from penetrated packages. Therefore, long-lived waste packages are important. The ...

Energy Technology Data Exchange (ETDEWEB)

In principle four different methods (ultrasound, microwaves, {gamma}-radiation and x-rays) are available for the non-destructive testing of refractories. Three of these methods, i.e. ultrasound, microwaves and {gamma}-radiation, are in use by different producers of AZS materials to carry out the quality control of their products. This paper will compare the three methods on the basis of the physical properties, present the existing devices, and show the advantages as well as the limits of the different methods. {gamma}-radiography, the oldest method in use, has one main disadvantage, which is the requirement of protection against radioactive radiation. Furthermore, while cracks and cavities can be detected with this method, structural changes can not be monitored. Therefore, the ultrasonic method was developed that allows to detect variations of porosity and grain size as well as cracks and voids when the ultrasonic parameters are tuned as well ...

Energy Technology Data Exchange (ETDEWEB)

We provide a detailed overview of an on-going, multinational test programme that is developing aerosol data for some spent fuel sabotage scenarios on spent fuel transport and storage casks. Experiments are being performed to quantify the aerosolised materials plus volatilised fission products generated from actual spent fuel and surrogate material test rods, due to impact by a high-energy/density device. The programme participants in the United States plus Germany, France and the United Kingdom, part of the international Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC) have strongly supported and coordinated this research programme. Sandia National Laboratories has the lead role for conducting this research programme; test programme support is provided by both the US Department of Energy and the US Nuclear Regulatory Commission. We provide a summary of the overall, multiphase test design and a description of all ...

Energy Technology Data Exchange (ETDEWEB)

The authors provide a detailed overview of an on-going, multinational test program that is developing aerosol data for some spent fuel sabotage scenarios on spent fuel transport and storage casks. Experiments are being performed to quantify the aerosolized materials plus volatilized fission products generated from actual spent fuel and surrogate material test rods, due to impact by a high-energy-density device. The program participants in the United States plus Germany, France and the United Kingdom, part of the international Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC) have strongly supported and coordinated this research program. Sandia National Laboratories has the lead role for conducting this research program; test program support is provided by both the US Department of Energy and the US Nuclear Regulatory Commission. The authors provide a summary of the overall, multiphase test design and a description of ...

Energy Technology Data Exchange (ETDEWEB)

As nuclear research has become more prevalent, environmental contamination from the disposal of radioactive waste has become a prominent issue. At Los Alamos National Laboratory (LANL) in northern New Mexico, radioactive contamination from disposal operations has raised some very specific concerns. Material Disposal Area G (Area G) is the primary low-level radioactive waste disposal site at LANL and occupies an area adjacent to land belonging to the Native American community of the Pueblo of San Ildefonso. Analyses of soil and vegetation collected from the perimeter of Area G have shown concentrations of radionuclides greater than background concentrations established for northern New Mexico. As a result, Pueblo residents had become concerned that contaminants from Area G could enter tribal lands through various ecological pathways. The residents specifically questioned the safety of consuming meat from ...

Energy Technology Data Exchange (ETDEWEB)

Potential maximum radiation dose rates were calculated for the former Alba Craft Laboratory site in Oxford, Ohio, which was involved in machining of uranium metal in the 1950s for the U.S. atomic energy program. The site is not currently being used. The residual radioactive material guidelines (RESRAD) computer code, which implements the methodology described in the US Department of Energy`s (DOE`s) manual for establishing residual radioactive material guidelines, was sued in this evaluation. Three potential land use scenarios were considered for the former Alba Craft site; the scenarios vary with regard to the type of site use, time spent at the site by the exposed individual, and sources of food consumed. Scenario A (a possible land use scenario) assumed industrial use of the site; Scenario B (a likely future land use scenario) assumed residential use of the site; and Scenario C (a possible but ...

International Nuclear Information System (INIS)

Black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electrons from a linear accelerator to a dose of 100 kGy and radioactivity was measured in order to estimate induced radioactivity in the irradiated foods. Induced radioactivity could not be detected significantly by #gamma#-ray spectrometry in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list of photonuclear reactions which could produce radioactivity below 10 MeV. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H_5_0 according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural ...

Energy Technology Data Exchange (ETDEWEB)

Preshocking delays initiation of PBX-9404 and PBX-9501, relative to unshocked material. In PBX-9404 preshock experiments, a first shock of 2.3 GPa was followed 0.65 {mu}s later by a second shock of 5.6 GPa. In PBX-9501, a preshock of 2.8 GPa and 0.32 us duration was followed by an initiating shock of 6.0 GPA. Both PBX explosives show clear desensitization while the preshock persists. In PBX-9404, initiation of detonation occurs nearly as anticipated for the material, after coalescence of the preshock and main shock into a single wave. Multiple embedded magnetic gauges were used to measure the shock histories. Our data indicates a slightly longer run to detonation than expected, even though a single wave is initiating the material. A slight stress reduction at coalescence, as required by the shock dynamics, may be responsible for the overrun. A reactive waste is clearly evident while the preshock ...

International Nuclear Information System (INIS)

Nanodimensional powders of cubic copper ferrite are synthesized by two-steps procedure of co-precipitation of copper and iron hydroxide carbonates, followed by mechanochemical treatment. X-ray powder diffraction, Moessbauer spectroscopy and temperature-programmed reduction are used for the characterization of the obtained materials. Their catalytic behavior is tested in methanol decomposition to hydrogen and CO and total oxidation of toluene. Formation of nanosized ferrite material is registered even after one hour of milling time. It is established that the prolonging of treatment procedure decreases the dispersion of the obtained product with the appearance of Fe2O3. It is demonstrated that the catalytic behavior of the samples depends not only on their initial phase composition, but on the concomitant ferrite phase transformations by the influence of the reaction medium. -- Graphical abstract: It is demonstrated that the catalytic behavior ...

Energy Technology Data Exchange (ETDEWEB)

An experiment was conducted on the structure of mesoscopic calculating method for cement-based composite materials. The purpose was utilization for the simulation of mesoscale failure processes and the development of new composite materials. Mesh split based on Voronoi polygons was applied as the discrete limit analysis of the cement-based composite materials containing aggregate particles taking the arrangement of random particles into consideration, and a two-dimensional rigid-body/spring model was employed as the model. The nonhomogeneity of concrete was represented by three kinds of different spring parameters which were aggregate, mortar matrix and their interfaces. The simulation results were summarized as follows: The stress-strain curve went into a non-linear state from the 30% of the maximum stress. The generation of interfacial crack started on the side of the aggregate, but the propagation of the crack was ...