WorldWideScience

Sample records for intermediate moessbauer levels

  1. Moessbauer spectroscopy

    Zemcik, T.

    1984-01-01

    The emission and absorption of photons taking place without changes in the frequency spectrum of the crystal lattice are known as the Moessbauer effect. It takes place in the low energy levels of heavy nuclei in solid lattices at low temperatures. On the basis of the hyperfine structure of Moessbauer spectra the notions are explained of isomer shift, quadrupole splitting and magnetic splitting. The principle and function are explained of Moessbauer spectrometers and the methods of graphical processing of spectra, also the use of the least square fit. Moessbauer spectroscopy is nondestructive, highly sensitive and selective and makes structural resolution possible. It is used for quantitative and qualitative analysis of compounds. Examples are given of the use of this method for mineralogical and crystallo-chemical analysis of lunar minerals and rocks, for analysis of corrosion products of iron and for phase analysis of alloys. (M.D.)

  2. Intermediate Levels of Visual Processing

    Nakayama, Ken

    1998-01-01

    ...) surface representation, here we have shown that there is an intermediate level of visual processing, between the analysis of the image and higher order representations related to specific objects; (2...

  3. Moessbauer spectroscopy. Tutorial book

    Yoshida, Yutaka; Langouche, Guido

    2013-01-01

    First textbook on Moessbauer Spectroscopy covering the complete field. Offers a concise introduction to all aspects of Moessbauer spectroscopy by the leading experts in the field. Tutorials on Moessbauer Spectroscopy. Since the discovery of the Moessbauer Effect many excellent books have been published for researchers and for doctoral and master level students. However, there appears to be no textbook available for final year bachelor students, nor for people working in industry who have received only basic courses in classical mechanics, electromagnetism, quantum mechanics, chemistry and materials science. The challenge of this book is to give an introduction to Moessbauer Spectroscopy for this level. The ultimate goal of this book is to give this audience not only a scientific introduction to the technique, but also to demonstrate in an attractive way the power of Moessbauer Spectroscopy in many fields of science, in order to create interest among the readers in joining the community of Moessbauer spectroscopists. This is particularly important at times where in many Moessbauer laboratories succession is at stake.

  4. Some Intermediate-Level Violin Concertos.

    Abramson, Michael

    1997-01-01

    Contends that many violin students attempt difficult concertos before they are technically or musically prepared. Identifies a variety of concertos at the intermediate and advanced intermediate-level for students to study and master before attempting the advanced works by Bach and Mozart. Includes concertos by Vivaldi, Leclair, Viotti, Haydn,…

  5. MNE Entrepreneurial Capabilities at Intermediate Levels

    Hoenen, Anne K.; Nell, Phillip Christopher; Ambos, Björn

    2014-01-01

    at intermediate geographical levels differ from local subsidiaries and global corporate headquarters, and why those differences are important. We illustrate our arguments using data on European regional headquarters (RHQs). We find that RHQs' entrepreneurial capabilities depend on their external embeddedness...... and on the heterogeneous information that is generated through dissimilar markets within the region. Our study opens up for an interesting discussion of the independence of these mechanisms. In sum, we contribute to the understanding of the entrepreneurial role of intermediate units in general and RHQs in particular....

  6. The ARES High-level Intermediate Representation

    Moss, Nicholas David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-03

    The LLVM intermediate representation (IR) lacks semantic constructs for depicting common high-performance operations such as parallel and concurrent execution, communication and synchronization. Currently, representing such semantics in LLVM requires either extending the intermediate form (a signi cant undertaking) or the use of ad hoc indirect means such as encoding them as intrinsics and/or the use of metadata constructs. In this paper we discuss a work in progress to explore the design and implementation of a new compilation stage and associated high-level intermediate form that is placed between the abstract syntax tree and when it is lowered to LLVM's IR. This highlevel representation is a superset of LLVM IR and supports the direct representation of these common parallel computing constructs along with the infrastructure for supporting analysis and transformation passes on this representation.

  7. Moessbauer spectroscopy

    Gonser, U.

    1975-01-01

    This book is addressed to persons interested in learning about what has been done and what can be done with Moessbauer spectroscopy. In an introductory chapter the basic principle is explained and the general parameters governing Moessbauer spectroscopy are tabulated. For the following chapters various disciplines are chosen and the wide applicability of this measuring technique is demonstrated. The second chapter discusses a few representative examples of chemical interesting information being reflected by isomer shifts and quadrupole splittings, particularly with respect to bonding and structural properties. The third chapter deals with some applications of Moessbauer spectroscopy for characterizing magnetic compounds and its use for magnetic structure investigations, particularly by making use of polarized radiation. The fourth chapter describes the use of the Moessbauer spectroscopy for studying iron in biological molecules. As an example of recent applications to mineralogy and geology the results of the studies of lunar samples are reviewed in the fifth chapter. Finally, in the last chapter, work is described on the use of Moessbauer spectroscopy in physical metallurgy, particularly quantitative analyses which have enabled metallurgists to solve many old problems. (orig./FW) [de

  8. Melting of metallic intermediate level waste

    Huutoniemi, Tommi; Larsson, Arne; Blank, Eva [Studsvik Nuclear AB, Nykoeping (Sweden)

    2013-08-15

    This report presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the authors' experience in operating a low level waste melting facility, their conclusion is that without technical improvements such a facility is not feasible today. This is based on the cost of constructing and operating such a facility, in conjunction with the radiological risks associated with operation and the uncertain benefits to disposal and long term safety.

  9. Melting of metallic intermediate level waste

    Huutoniemi, Tommi; Larsson, Arne; Blank, Eva

    2013-08-01

    This report presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the authors' experience in operating a low level waste melting facility, their conclusion is that without technical improvements such a facility is not feasible today. This is based on the cost of constructing and operating such a facility, in conjunction with the radiological risks associated with operation and the uncertain benefits to disposal and long term safety

  10. Treatment of low and intermediate level wastes

    Hoehlein, G.

    1978-05-01

    The methods described of low and intermediate level waste treatment are based exclusively on operating experience gathered with the KfK facilities for waste management, the Karlsruhe Reprocessing Plant (WAK), the ALKEM fuel element fabrication plant, the MZFR, KNK and FR 2 reactors as well as at the Karlsruhe Nuclear Research Center and at the state collecting depot of Baden-Wuerttemberg. The processing capacities and technical status are similar to that in 1976. With an annual throughput of 10000 m 3 of solid and liquid raw wastes, an aggregate activity of 85000 Ci, 500 kg of U and 2 kg of Pu, final waste in the amount of 500 m 3 was produced which was stored in the ASSE II salt mine. (orig.) [de

  11. Colloids related to low level and intermediate level waste

    Ramsay, J.D.F.; Russell, P.J.; Avery, R.G.

    1991-01-01

    A comprehensive research investigation has been undertaken to improve the understanding of the potential role of colloids in the context of disposal and storage of low level and intermediate level waste immobilized in cement. Several topics have been investigated which include: (a) the study of the formation and characteristics of colloids in cement leachates; (b) the effects of the near-field aqueous chemistry on the characteristics of colloids in repository environments; (c) colloid sorption behaviour; (d) interactions of near-field materials with leachates; (e) characteristics of near-field materials in EC repository simulation tests; and (f) colloid migration behaviour. These experimental investigations should provide data and a basis for the development of transport models and leaching mechanisms, and thus relate directly to the part of the Task 3 programme concerned with migration and retention of radionuclides in the near field. 114 Figs.; 39 Tabs.; 12 Refs

  12. Quantitative Moessbauer analysis

    Collins, R.L.

    1978-01-01

    The quantitative analysis of Moessbauer data, as in the measurement of Fe 3+ /Fe 2+ concentration, has not been possible because of the different mean square velocities (x 2 ) of Moessbauer nuclei at chemically different sites. A method is now described which, based on Moessbauer data at several temperatures, permits the comparison of absorption areas at (x 2 )=0. (Auth.)

  13. The management of intermediate level wastes in Sweden

    Hultgren, Aa.; Thegerstroem, C.

    1980-01-01

    A brief overview of current practices and research in Sweden on the management of intermediate level wastes is given. Intermediate level wastes include spent resins, filters and core components from the six power reactors in operation; radioactive wastes from nuclear fuel development at Studsvik and from non-nuclear applications are a minor contribution. (Auth.)

  14. Implication of the level mixing concept on the possibility of Moessbauer absorption on isotopes with a long lived excited state

    Coussement, R.; Scheveneels, G.; Hardeman, F.; Boolchand, P.

    1988-01-01

    In proposals and designs of possible γ-lasers, called grasers, the resonant absorption of γ-rays, called Moessbauer absorption, plays a dominant role. However two conflicting requirements on the lifetime of the isomeric state result in poor perspectives. In order to achieve the inversion of population that is necessary for the laser working, a long lived state is preferred so that the inverted system could be prepared by radiochemical means. However a long lived state implies a very small natural linewidth. At the other hand one needs a linewidth that is at least of the same order of magnitude as the inhomogeneous energy spread due to imperfections in the crystalline surrounding or due to dipole-dipole interactions with the nearest neighbours. One can circumvent the stringent requirement on the natural linewidth, when the effective lifetime is much shorter than the radiative one. The effective lifetime is in fact nothing else than the coherence time of the quantum state. If this coherence is only broke by the radiative decay, one obtains the natural linewidth. If, however, the nucleus is strongly coupled to the reservoir of its surrounding, it makes frequent phase and energy jumps. Its correlation time becomes very short and the associated linewidth becomes strongly but homogeneously broadened. To couple the nucleus with its neighbours and with the reservoir we use the principles of resonant level mixing. We will describe and illustrate this method with the case of 109m Ag. (orig./BHO)

  15. Acceptance criteria for deposition of low-level and intermediate-level radiation levels radioactive wastes

    2002-09-01

    This norm establishes the criteria for acceptance low and intermediate radiation level for safe deposition in repositories, for assuring the protection of workers, population and environment against the hazardous effects of the ionizing radiations. The criteria of this norm applies to the low and intermediate radiation levels

  16. Disposal of high level and intermediate level radioactive wastes

    Flowers, R.H.

    1991-01-01

    The waste products from the nuclear industry are relatively small in volume. Apart from a few minor gaseous and liquid waste streams, containing readily dispersible elements of low radiotoxicity, all these products are processed into stable solid packages for disposal in underground repositories. Because the volumes are small, and because radioactive wastes are latecomers on the industrial scene, a whole new industry with a world-wide technological infrastructure has grown up alongside the nuclear power industry to carry out the waste processing and disposal to very high standards. Some of the technical approaches used, and the Regulatory controls which have been developed, will undoubtedly find application in the future to the management of non-radioactive toxic wastes. The repository site outlined would contain even high-level radioactive wastes and spent fuels being contained without significant radiation dose rates to the public. Water pathway dose rates are likely to be lowest for vitrified high-level wastes with spent PWR fuel and intermediate level wastes being somewhat higher. (author)

  17. Colloids related to low level and intermediate level waste

    Ramsay, J.D.F.; Russell, P.J.; Avery, R.G.

    1991-03-01

    A comprehensive investigation has been undertaken to improve the understanding of the potential role of colloids in the context of disposal and storage of low and intermediate level waste immobilised in cement. Several topics have been investigated using a wide range of advanced physico-chemical and analytical techniques. These include: (a) the study of formation and characteristics of colloids in cement leachates, (b) the effects of the near-field aqueous chemistry on the characteristics of colloids in repository environments, (c) colloid sorption behaviour, (d) interactions of near-field materials with leachates, and (e) preliminary assessment of colloid migration behaviour. It has been shown that the generation of colloids in cement leachates can arise from a process of nucleation and growth leading to an amorphous phase which is predominantly calcium silicate hydrate. Such colloidal material has a capacity for association with polyvalent rare earths and actinides and these may be significant in the source term and processes involving radionuclide retention in the near field. It has also been shown that the near-field aqueous chemistry (pH, Ca 2+ concentration) has a marked effect on colloid behaviour (deposition and stability). A mechanistic approach to predict colloid sorption affinity has been developed which highlights the importance of colloid characteristics and the nature of the ionic species. (author)

  18. Packaging and transport of low and intermediate level radioactive waste

    Smith, M.J.S.; Streatfield, R.E.

    1987-02-01

    The paper presents an overview of Nirex proposals for the packaging and transport of low and intermediate-level radioactive waste, as well as the regulatory requirements which must be met in such operations. (author)

  19. A driving system for Moessbauer spectrometer

    Maslan, M.; Cholmeckij, A.; Evdokimov, V.; Misevic, O.; Fedorov, A.; Zak, D.

    1993-01-01

    The driving system of a Moessbauer spectrometer is described. The system comprises a minivibrator, a digital generator of the reference velocity signal, and circuits for controlling the vibrator. The reference velocity signal is stored by the control computer in an intermediate storage. The feedback in the control circuits includes correction for nonlinearity of the driving facility. A Moessbauer spectrometer which is equipped with this driving system exhibits a velocity scale nonlinearity below 0.1%. The resonance line width for sodium nitroprusside is 0.27 ± 0.01 mm/s. (author). 6 figs., 8 refs

  20. CONDITIONING OF INTERMEDIATE-LEVEL WASTE AT FORSCHUNGSZENTRUM JUELICH GMBH

    Krumbach, H.

    2003-01-01

    This contribution to the group of low-level, intermediate, mixed and hazardous waste describes the conditioning of intermediate-level mixed waste (dose rate above 10 mSv/h at the surface) from Research Centre Juelich (FZJ). Conditioning of the waste by supercompaction is performed at Research Centre Karlsruhe (FZK). The waste described is radioactive waste arising from research at Juelich. This waste includes specimens and objects from irradiation experiments in the research reactors Merlin (FRJ-1) and Dido (FRJ-2) at FZJ. In principle, radioactive waste at Forschungszentrum Juelich GmbH is differentiated by the surface dose rate at the waste package. Up to a surface dose rate of 10 mSv/h, the waste is regarded as low-level. The radioactive waste described here has a surface dose rate above 10 mSv/h. Waste up to 10 mSv/h is conditioned at the Juelich site according to different conditioning methods. The intermediate-level waste can only be conditioned by supercompaction in the processing facility for intermediate-level waste from plant operation at Research Centre Karlsruhe. Research Centre Juelich also uses this waste cell to condition its intermediate-level waste from plant operation

  1. PNGMDR - Characterisation of intermediate-level long-lived wastes

    2014-12-01

    This document presents the status of the characterization of intermediate-level long-lived wastes which are warehoused on exploited EDF sites or which will be produced during the deconstruction of first-generation reactors. It addresses aspects related to characterisation and packaging of wastes produced before 2015. More specifically, it addresses aspects related to contamination and to activation. Contamination is assessed by measurements whereas activation assessment is based on numerical simulations associated with measurements performed during parcel production. After having mentioned the concerned reactors, the document presents the methodology adopted for these assessments, and reports the progress status of the characterization process for these intermediate-level long-lived wastes

  2. Vertical Integration at Junior and Intermediate Levels. School Research Newsletter.

    Marklund, Inger, Ed.; Hanse, Mona-Britt, Ed.

    1984-01-01

    In recent years, there has been a rapid growth of interest in Sweden in vertically integrated classes in compulsory schools, especially at junior high school and intermediate grade levels. This development is supported in various ways by the curriculum, partly because it puts more emphasis than previous curricula on the occurrence of teaching…

  3. Intermediate-Level Knowledge in Child-Computer Interaction

    Barendregt, Wolmet; Torgersson, Olof; Eriksson, Eva

    2017-01-01

    Based on an analysis of all papers at IDC from 2003 to 2016 this paper urges the Child-Computer Interaction (CCI) field to start formulating intermediate-level knowledge, in the form of e.g. strong concepts. Our analysis showed that 40% of all papers at the Interaction Design and Children...... conference presents the design of an artefact accompanied by an evaluation (to which we will refer as 'artefact-centered' papers). While exploring the design space in the form of artefacts is important and valuable, it can be argued that those artefact-centered papers generally make a smaller contribution...... to the field as a whole, which is also visible in the number of citations to such papers in comparison to the number of citations to other kinds of papers. As a first step towards more intermediate-level knowledge, we have thus attempted to formulate and ground three suggestions for strong concepts in CCI...

  4. DISPOSAL OF LOW AND INTERMEDIATE LEVEL WASTE IN HUNGARY

    Bálint Nős

    2012-07-01

    Full Text Available There are two operating facilities for management of low and intermediate level radioactive waste in Hungary. Experience with radioactive waste has a relatively long history and from its legacy some problems are to be solved, like the question of the historical waste in the Radioactive Waste Treatment and Disposal Facility (RWTDF. Beside the legacy problems the current waste arising from the Nuclear Power Plant (NPP has to be dealt with a safe and economically optimized way.

  5. Containers for packaging of solid and intermediate level radioactive wastes

    1993-01-01

    Low and intermediate level radioactive wastes are generated at all stages in the nuclear fuel cycle and also from the medical, industrial and research applications of radiation. These wastes can potentially present risks to health and the environment if they are not managed adequately. Their effective management will require the wastes to be safely stored, transported and ultimately disposed of. The waste container, which may be defined as any vessel, drum or box, made from metals, concrete, polymers or composite materials, in which the waste form is placed for interim storage, for transport and/or for final disposal, is an integral part of the whole package for the management of low and intermediate level wastes. It has key roles to play in several stages of the waste management process, starting from the storage of raw wastes and ending with the disposal of conditioned wastes. This report provides an overview of the various roles that a container may play and the factors that are important in each of these roles. This report has two main objectives. The first is to review the main requirements for the design of waste containers. The second is to provide advice on the design, fabrication and handling of different types of containers used in the management of low and intermediate level radioactive solid wastes. Recommendations for design and testing are given, based on the extensive experience available worldwide in waste management. This report is not intended to have any regulatory status or objectives. 56 refs, 16 figs, 10 tabs

  6. Moessbauer studies of Inca ceramics

    Wagner, U.; Wagner, F.E.; Marticorena, B.; Salazar, R.; Schwabe, R.; Riederer, J.

    1986-01-01

    To obtain information on the firing of Inca ceramics, 7 samples from different locations were studied by Moessbauer spectroscopy including a detailed laboratory refiring procedure. The glaze typical for the surface of this ware was studied by Moessbauer scattering. (Auth.)

  7. Treatment of low- and intermediate-level solid radioactive wastes

    1983-01-01

    One of the essential aims in the waste management is to reduce as much as possible the waste volumes to be stored or disposed of, and to concentrate and immobilize as much as possible the radioactivity contained in the waste. This document describes the treatment of low- and intermediate-level solid waste prior to its conditioning for storage and disposal. This report aims primarily at compiling the experience gained in treating low- and intermediate-active solid wastes, one of the major waste sources in nuclear technology. Apart from the description of existing facilities and demonstrated handling schemes, this report provides the reader with the basis for a judgement that facilitates the selection of appropriate solutions for a given solid-waste management problem. It thus aims at providing guidelines in the particular field and indicates new promising approaches that are actually under investigation and development

  8. Low- and intermediate-level waste management practices in Canada

    Charlesworth, D.H.

    1982-05-01

    Low- and intermediate-level wastes arise in Canada from the operation of nuclear power stations, nuclear research establishments, nuclear fuel and radioisotope production facilities, as well as from many medical, research and industrial organizations. Essentially all of the solid radioactive wastas are stored in a retrievable fashion at five waste management areas from which a portion is expected to be transferred to future disposal facilities. Waste processing for volume reduction and stabilization is becoming an increasingly important part of low-level waste management because of the advantages it provides for both interim storage currently, and permanent disposal in the future

  9. Treatment of low- and intermediate-level liquid radioactive wastes

    1984-01-01

    This report aims at giving the reader details of the experience gained in the treatment of both low- and intermediate-level radioactive liquid wastes. The treatment comprises those operations to remove radioactivity from the wastes and those that change only its chemical composition, so as to permit its discharge. Considerable experience has been accumulated in the satisfactory treatment of such wastes. Although there are no universally accepted definitions for low- and intermediate-level liquid radioactive wastes, the IAEA classification (see section 3.2) is used in this report. The two categories differ from one another in the fact that for low-level liquids the actual radiation does not require shielding during normal handling of the wastes. Liquid wastes which are not considered in this report are those from mining and milling operations and the high-level liquid wastes resulting from fuel reprocessing. These are referred to in separate IAEA reports. Likewise, wastes from decommissioning operations are not within the scope of this report. Apart from the description of existing methods and facilities, this report is intended to provide advice to the reader for the selection of appropriate solutions to waste management problems. In addition, new and promising techniques which are either being investigated or being considered for the future are discussed

  10. Operating safety requirements for the intermediate level liquid waste system

    1980-07-01

    The operation of the Intermediate Level Liquid Waste (ILW) System, which is described in the Final Safety Analysis, consists of two types of operations, namely: (1) the operation of a tank farm which involves the storage and transportation through pipelines of various radioactive liquids; and (2) concentration of the radioactive liquids by evaporation including rejection of the decontaminated condensate to the Waste Treatment Plant and retention of the concentrate. The following safety requirements in regard to these operations are presented: safety limits and limiting control settings; limiting conditions for operation; and surveillance requirements. Staffing requirements, reporting requirements, and steps to be taken in the event of an abnormal occurrence are also described

  11. Design of a store for encapsulated intermediate level radioactive waste

    Lloyd, A.I.; Robinson, G.; Price, M.S.T.

    1989-01-01

    The design of a new store for cemented intermediate level radioactive waste produced in unshielded 500 litre drums from the Winfrith Radwaste Treatment Plant is described. The store design has had to take account of local site constraints and disposal uncertainties. As a result, an innovative above ground storage tube design using interlocking, commercially available, concrete pipe rings has been selected. Other special features are that the store is easily capable of being extended whilst in service and is simple and cheap to decommission. A quality assessment facility for the drummed waste is an integral part of the store complex. (author)

  12. Low and intermediate level waste repositories: public involvement aspects

    Ferreira, Vinicius V.M.; Mourao, Rogerio P.; Fleming, Peter M.; Soares, Wellington A.; Braga, Leticia T.P.; Santos, Rosana A.M.

    2009-01-01

    The nuclear energy acceptance creates several problems, and one of the most important is the disposal of the radioactive waste. International experiences show that not only environmental, radiological and technical questions have to be analyzed, but the public opinion about the project must be considered. The objective of this article is to summarize some public involvement aspects associated with low and intermediate level waste repositories. Experiences from USA, Canada, South Africa, Ukraine and other countries are studied and show the importance of the population in the site selection process for a repository. (author)

  13. Moessbauer spectroscopy in space

    Klingelhoefer, G [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Held, P [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Teucher, R [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Schlichting, F [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Foh, J [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Kankeleit, E [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik

    1995-03-01

    Nearly 40 years after the discovery of the Moessbauer effect for the first time a Moessbauer spectrometer will leave our planet to explore in situ the surface of another solar system body: the red planet Mars [1]. We are currently developing a miniaturized Moessbauer spectrometer (MIMOS) which is part of the scientific payload of the Russian Mars96 mission, to be launched within the next 2-4 years [2,3]. To fulfill the requirements for a space mission to the planet Mars, all parts of the spectrometer had to be extremely miniaturized and ruggedized to withstand the space flight and Mars environmental conditions. The relevant parts (e.g. drive, detector system, electronics etc.) will be described in more detail and its characteristics compared to standard systems. Because of this new development there now is a growing interest to include a Moessbauer (MB) instrument in future space missions to other solar system bodies as for instance Venus, the terrestrial Moon, and a comet nucleus. Because of extremely different environmental conditions (e.g. nearly zero gravity on the surface of a comet nucleus, high pressure and temperature on the surface of Venus, etc.) different instrument designs and concepts are required for different missions. We will present some ideas for various types of missions, as well as the motivation for using Moessbauer spectroscopy in these cases. (orig.)

  14. Experimental study on intermediate level radioactive waste processing

    Nagakura, Tadashi; Abe, Hirotoshi; Okazawa, Takao; Hattori, Seiichi; Maki, Yasuro

    1977-01-01

    In the disposal of intermediate level radioactive wastes, multilayer package will be adopted. The multilayer package consists of cement-solidified waste and a container such as a drum - can with concrete liner or a concrete container. So, on the waste to be cement-solidified in such container, experimental study was carried out as follows. (1) Cement-solidification method. (2) Mechanical behaviour of cement-solidified waste. The mechanical behaviour of the containers was studied by the finite element method and experiment, and the function of pressure-balancing valves was also studied. The following data on processing intermediate level radioactive wastes were obtained. (1) In the case of cement-solidified waste, the data to select the suitable solidifying material and the standard mixing proportion were determined. (2) The basic data concerning the uniaxial compressive strength of cement-solidified waste, the mechanical behaviour of cement-solidified waste packed in a drum under high hydrostatic pressure, the shock response of cement-solidified waste at the time of falling and so on were obtained. (3) The pressure-balancing valves worked at about 0.5 Kg/cm 2 pressure difference inside and outside a container, and the deformation of a drum cover was 10 to 13 mm. In case of the pressure difference less than 0,5 Kg/cm 2 , the valves shut, and water flow did occur. (auth.)

  15. Low and intermediate level radioactive waste processing in plasma reactor

    Sauchyn, V.; Khvedchyn, I.; Van Oost, G.

    2013-01-01

    Methods of low and intermediate level radioactive waste processing comprise: cementation, bituminization, curing in polymer matrices, combustion and pyrolysis. All these methods are limited in their application in the field of chemical, morphological, and aggregate composition of material to be processed. The thermal plasma method is one of the universal methods of RAW processing. The use of electric-arc plasma with mean temperatures 2000 - 8000 K can effectively carry out the destruction of organic compounds into atoms and ions with very high speeds and high degree of conversion. Destruction of complex substances without oxygen leads to a decrease of the volume of exhaust gases and dimension of gas cleaning system. This paper presents the plasma reactor for thermal processing of low and intermediate level radioactive waste of mixed morphology. The equipment realizes plasma-pyrolytic conversion of wastes and results in a conditioned product in a single stage. As a result, the volume of conditioned waste is significantly reduced (more than 10 times). Waste is converted into an environmentally friendly form that suits long-term storage. The leaching rate of macro-components from the vitrified compound is less than 1.10 -7 g/(cm 2 .day). (authors)

  16. Low and intermediate level radioactive waste in Mexico

    Paredes, L.C.; Ortiz, J.R.; Sanchez, S.

    2002-01-01

    Currently, it is necessary to establish, in a few years, a definitive repository for low and intermediate level radioactive waste in order to satisfy the necessities of Mexico for the next 50 years. Consequently, it is required to estimate the volumes of the radioactive waste generated annually, the stored volumes to-date and their projection to medium-term. On this subject, the annual average production of low and intermediate level radioactive waste from the electricity production by means of nuclear power reactors is 250 m 3 /y which consist of humid and dry solid waste from the 2 units of the Laguna Verde Nuclear Power plant having a re-use efficiency of effluents of 95%. On the other hand, the applications in medicine, industry and research generate 20 m 3 /y of solid waste, 280 m 3 /y of liquid waste and approximately 10 m 3 /y from 300 spent sealed radioactive sources. The estimation of the total volume of these waste to the year 2035 is 17500 m 3 corresponding to the 46% of the volume generated by the operation and maintenance of the 2 units of the Laguna Verde Nuclear Power plant, 34% to the decommissioning of these 2 units at the end of their useful life and 20% to the waste generated by applications in medicine, industry and research. (author)

  17. Moessbauer investigations of itmid

    Mrayed, Y.S.; Ellid, M.S.; Fallagh, F.A.

    1996-01-01

    A sample of itmid available commercially was obtained and investigated using 57 Fe Moessbauer spectroscopy, atomic absorption, X-ray fluorescence. The Moessbauer spectra showed the presence hematite (alpha-Fe 2 O 3 ), goethite (alpha-FeOOH), and a third phase which has a six-line spectrum with the following parameters : Isomer shift (gamma= 0.52 mm/s), magnetic field (H=290 kOe). After conducting a series of reduction and calcination to the itmid sample and with the aid of atomic absorption and X-ray fluorescence results the third phase was identified as the iron sulfide compound FeS. 3 figs., 3 tabs

  18. Concrete conditioners for low-intermediate level nuclear wastes

    Roehl, J.L.; Lorentz, R.G.; Franzen, H.R.

    1986-01-01

    The conditioning of low-intermediate level radioactive waste disposal, in Brazil, with concrete packages designed in such way that, in spite of being destined to receive compacted materials in long term sub-surface disposal, they may also be able to attend other storage or disposal necessities, is analysed. A design of a reinforced concrete package with a net volume of 360 l and, with compatible diameter to contain compacted 200 l drums, was developed. A study on compactation of 200 l steel packages is done. A pressure of 30.000 KN for compacting these 200 l drums was adapted, and two series of tests to verify the pressure volume reduction ratio and, the final dimensions and density of the compacted elements, was executed. (Author) [pt

  19. Nirex plans for low and intermediate level waste

    Mathieson, J.

    1995-01-01

    Two main events have dominated Nirex's recent history: the Radioactive Waste Review and the Company's plans to build a Rock Characterisation facility at its investigation site near Sellafield in Cumbria. The outcome of the former was announced in a White Paper in July 1995. Decisions on the RCF are subject to a public inquiry starting in September 1995. Given a successful result and confirmation that the site could meet the safety target, a deep repository for intermediate and some low level waste could be available by 2011 or thereabouts. As financing of Nirex's activities is in line with the ''polluter pays'' principle, the Company is aiming to deliver a cost-effective disposal system which complies fully with the stringent safety requirements placed on it. (author)

  20. Conditioning of low- and intermediate-level radioactive wastes

    1983-01-01

    The nuclear fuel cycle, together with the use of separated radioisotopes, in many endeavours generates a variety of low- and intermediate-level radioactive wastes. These waste materials contain quantities of radionuclides sufficient to present potential health risks to people if the wastes are not adequately managed, but usually insufficient quantities to require heat removal. Adequate management involves a series of steps which lead from the arising of the wastes to their safe disposal, steps which may include collection, segregation, treatment, volume reduction, conditioning, transport, interim storage and disposal. Each step is defined by the need to accommodate to the preceding one and to facilitate the ones that follow. This technical report describes primarily the technologies available for the conditioning steps (i.e., immobilization and packaging) and relates them to the other steps. In broad terms, the purpose of conditioning is to convert the wastes into packages that are suitable for transport, storage and disposal

  1. Management for low and intermediate level wastes in Brazil

    Franzen, H.R.

    1986-01-01

    A research and demonstration project was developed, to offer management options for low and intermediate level radioactive wastes. The project considered: the experience of other countries; the laws and regulations according to internationally accepted standards; criteria and recommendations; the technical, socio-political realities, and the expectation of our countrie related to the nuclear power plants. Preliminary guidelines for waste acceptance critetia were established. The solution for shallow land burial was a multibarrier system. Since, there is no final decision about the repository localization it was decided that the waste produced by nuclear power plants will be kept on-site and those from medicine, agriculture, industry and research are sent to the IPEN/CNEN-SP for treatment and temporary storage. (Author/M.C.K.) [pt

  2. Treatment and immobilization of intermediate level radioactive wastes

    Lerch, R.E.; Greenhalgh, W.O.; Partridge, J.A.; Richardson, G.L.

    1977-01-01

    This paper discusses a new program underway to develop and demonstrate treatment and immobilization technologies for intermediate level wastes (ILW) generated in the nuclear fuel cycle. Initial work has defined the sources, quantities and types of wastes which comprise ILW. Laboratory studies are underway to define treatment technologies for liquid ILW which contains volatile contaminants and to define immobilization parameters for the residues resulting from treatment of ILW. Immobilization agents initially being evaluated for the various residues include cement, urea-formaldehyde, and bitumen although other immobilization agents will be studied. The program also includes development of acceptable test procedures for the final immobilized products as well as development of proposed criteria for storage, transportation, and disposal of the immobilized ILW. 20 figures, 10 tables

  3. Some analytical aspects of the Moessbauer spectrometry

    Meisel, W.

    1975-01-01

    Analytical applications of Moessbauer spectrometry are reviewed. Various methods of analysis (qualitative, semiquantitative and quantitative) using the Moessbauer effect are dealt with. Sensitivity and accuracy of Moessbauer spectrometry in analytical applications are discussed. (Z.S.)

  4. Reinforced concrete in the intermediable-level nuclear waste repository

    Duffo, Gustavo

    2009-01-01

    The National Atomic Energy Commission (CNEA) is responsible for developing the nuclear waste disposal management programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The proposed model is a near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers and the model foresees a period of 300 years of institutional post-closure control. Since the vault and cover are major components of the engineered barriers, the durability of these concrete structures is an important aspect for the facility integrity. This work presents laboratory investigations performed on the corrosion susceptibility of steel rebars embedded in two different types of high performance reinforced concretes, recently developed by the National Institute of Industrial Technology (Argentine). Concretes were made with cement with Blast Furnace Slag (CAH) and Silica Fume cement (CAH + SF). The aim of this work is to predict the service life of the intermediate level radioactive waste disposal vaults from data obtained from electrochemical techniques. Besides, the diffusion coefficients of aggressive species, such as chloride and carbon dioxide, were also determined. On the other hand, data obtained with corrosion sensors embedded in a vault prototype is also included. These sensors allow on-line measurements of several parameters related to the corrosion process such as rebar corrosion potential and corrosion current density; incoming oxygen flow that reaches the metal surface; concrete electrical resistivity; chloride concentration and internal concrete temperature. All the information obtained from both, laboratory tests and sensors will be used for the final design of the container in order to achieve a service life more or equal than the foreseen durability for this type of

  5. Polarized Moessbauer transitions

    Barb, D.

    1975-01-01

    Theoretical aspects of the emission, absorption and scattering of polarized gamma rays are reviewed for a general case of combined magnetic and electric hyperfine interactions; various possibilities of obtaining polarized gamma sources are described and examples are given of the applications of Moessbauer spectroscopy with polarized gamma rays in solving problems of solid state physics. (A.K.)

  6. Moessbauer characteristics of glauconitisation

    Kuzmann, E.; Weiszburg, T. G.; Toth, E.; Garg, V. K.

    2008-01-01

    57 Fe Moessbauer spectroscopy, X-ray diffraction and local (WDX, EDX) and bulk chemical methods (ICP-AES complemented with Fe 2+ titration) were used to study glauconites originating from three sandstone samples (NY1, NY3 and EWT) of the Upper Oligocene Eger Formation (Northern Hungary). The, during glauconitisation, increasing aggregate density and magnetic susceptibility offered a unique possibility to separate grains of different evolutionary stage from the same glauconite population. 57 Fe Moessbauer spectra of both structurally and chemically well characterised glauconite fractions were decomposed into four doublets. Two-two of the doublets were assigned to octahedral Fe 2+ and octahedral Fe 3+ . Fe 2+ /Fe values determined by Moessbauer measurements were used for the calculation of the chemical formula of glauconite samples [including octahedral occupancy (B O ) and octahedral charge (X O ) as well]. The gradual increase of Fe 2+ /Fe was documented with the increase of aggregate density in correlation with the foregoing of glauconitisation. Our results give a quantitative demonstration that octahedral occupancy (B O ) decrease and the substitution of octahedral Al by Fe 2+ are the major processes allowing the interlayer K incorporation during glauconitisation. The systematic crystalchemical evolution as reflected in the systematic changes of the Moessbauer data are discussed in terms of the subsequent steps of glauconitisation.

  7. Treatment and immobilization of intermediate-level radioactive wastes

    Lerch, R.E.; Greenhalgh, W.O.; Partridge, J.A.; Richardson, G.L.

    1979-01-01

    A new program underway at the Hanford Engineering Development Laboratory (HEDL) to develop and demonstrate treatment and immobilization technologies for intermediate-level wastes (ILW) generated in the nuclear fuel cycle is discussed. ILW are defined as those liquid and solid radioactive wastes, other than high-level wastes and fuel cladding hulls, that in packaged form have radiation dose readings greater than 200 millirem/hr at the packaged surface and 10 millirem/hr at three feet from the surface. The IAEA value of 10 4 Ci/m 3 for ILW defines the upper limit. For comparative purposes, reference is also made to certain aspects of low-level radioactive wastes (LLW). Initial work has defined the sources, quantities and types of wastes which comprise ILW. Because of the wide differences in composition (e.g., acids, salt solutions, resins and zeolites, HEPA filters, etc.) the wastes may require different treatments, particularly those wastes containing volatile contaminants. The various types of ILW have been grouped into categories amenable to similar treatment. Laboratory studies are underway to define treatment technologies for liquid ILW which contain volatile contaminants and to define immobilization parameters for the residues resulting from treatment of ILW. Immobilization agents initially being evaluated for the various residues include cement, urea-formaldehyde, and bitumen although other immobilization agents will be studied. The program also includes development of acceptable test procedures for the final immobilized products as well as development of proposed criteria for storage, transportation, and disposal of the immobilized ILW

  8. STUTTERING THERAPY FOR A CHILD AT INTERMEDIATE STUTTERING LEVEL

    Nevzeta SALIHOVIKJ

    2009-11-01

    Full Text Available Stuttering therapy very often demands combination of various approaches or its modification. The main purpose of this study was to present an integrated approach to stuttering modification therapy and fluency shaping therapy for an intermediate school-age male stutterer (11 years old.The therapy for the child lasted for 12 months, sessions have been carried out twice a week, each session lasted for 45 minutes. The child still attends the therapy. The therapy uses integration of stuttering modification therapy and fluency shaping therapy. For the purpose of the fluency shaping therapy, delayed auditory feedback program is applied. During the stuttering modification therapy the child has been taught how to stutter more easily which implies prolongation of all sounds in words on which child stutters, with easy and soft transition from one sound to another. It is continuously being worked with the child on reducing negative feelings and attitudes as well as elimination of avoidance of words and speaking situations. We explained to the parents the treatment program and their role in the program realization. We also explained the possible causes of stuttering, and tried to identify and reduce fluency distractors, and engage the child in as many situations as possible which improved speech fluency.After the application of this program the child has improved fluency during the conversation in clinical and nonclinical conditions (environment. This fluency consists of spontaneous and controlled fluency. Furthermore, fear of speaking and avoidance of speech situations are significantly reduced. On the basis of the applied therapy on the child at intermediate stuttering level it can be concluded that it is possible to integrate successfully both approaches: stuttering modification therapy and fluency shaping therapy.

  9. Policy and technical considerations for intermediate-level and low-level radioactive waste

    Anon.

    1977-01-01

    This section has addressed issues, topics, and considerations related to low-level and intermediate-level wastes that are basic to developing and establishing environmental radiation protection criteria for radioactive wastes. Applicability of criteria, criteria considerations for sites, control of radiological impact to the population, and long-term considerations are discussed

  10. Resonance detection of Moessbauer radiation

    Morozov, V.V.

    1985-01-01

    The resonance detection method as compared with the usual method of registering Moessbauer spectra has a number of advantages, one of which is the increase of resolution of the Moessbauer spectrum. The method is based on the modulation of a secondary radiation of a converter tuned in the resonance with the Moessbauer gamma-quantum source. The resonance detection method with account of supression, secondary radiation outgoing from the converter is investigated. The converter represents a substrate enriched by the Moessbauer isotope placed either inside the gas counter, or coupled with any other detecting device. Analytical expressions for Moessbauer spectrum parameters: effect, area and width of the spectral line are derived. It is shown that the joint application of usual and resonance detection methods for registering the Moessbauer spectrum allows one to determine parameters of the source, converter and the investigated absorber

  11. Bituminization of low- and intermediate-level radioactive concentrates

    Breza, M.; Krejci, F.; Timulak, J.; Tibensky, L.

    1985-01-01

    The results and experiences are summed up from the research and development of the technology of bituminization of low- and intermediate-level radioactive concentrates generated in the operation of nuclear power plants with WWER-440 reactors. The experiments took place on a pilot plant bituminization line with various model solutions at an evaporator capacity of 70, 100 and 140 litres per hour. The composition of the solutions changed in dependence on the knowledge of the composition of actual concentrates in the V-1 nuclear power plant at Jaslovske Bohunice. The following factors were studied in the concentrate: the effect of its pH, its borate content and content of metal carbonates, the content of organic acid salts, the content of detergents, etc., on the process of bituminization. Physico-chemical conditions are described under which the operation of the evaporator was fail-safe and filling of the bituminization product with salts homogeneous. A low water content of up to 1% was achieved. The properties of the bituminization product were negatively affected by a high level of heavy metal oxides, surfactants, oxalates and citrates. In order to improve the properties of the product it will be necessary to replace bitumen emulsion Silembit-60 used as reinforcement matrix, by a different type of bitumen. (Z.M.)

  12. Progress on the national low level radioactive waste repository and national intermediate level waste store

    Perkins, C.

    2003-01-01

    The Australian Government is committed to establishing two purpose-built facilities for the management of Australia's radioactive waste; the national repository for disposal of low level and short-lived intermediate level ('low level') waste, and the national store for storage of long-lived intermediate level ('intermediate level') waste. It is strongly in the interests of public security and safety to secure radioactive waste by disposal or storage in facilities specially designed for this purpose. The current arrangements where waste is stored under ad hoc arrangements at hundreds of sites around Australia does not represent international best practice in radioactive waste management. Environmental approval has been obtained for the national repository to be located at Site 40a, 20 km east of Woomera in South Australia, and licences are currently being sought from the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) to site, construct and operate the facility. The national repository may be operating in 2004 subject to obtaining the required licences. The national store will be located on Australian Government land and house intermediate level waste produced by Australian Government departments and agencies. The national store will not be located in South Australia. Short-listing of potentially suitable sites is expected to be completed soon

  13. Management of low- and intermediate level waste in Sweden

    Carlsson, Jan

    1999-01-01

    This presentation describes how the management of radioactive waste is organised in Sweden, where Swedish law places the responsibility for such management with the waste generators. The four nuclear utilities have formed a joint company, the Swedish Nuclear Fuel and Waste Management Co., SKB, to handle the nuclear waste. The Swedish waste management system includes a final repository for short-lived low level waste (LLW) and intermediate level waste (ILW) and an interim storage facility for spent nuclear fuel and long-lived waste. Some very low-level, short-lived waste is disposed of in shallow-land repositories at the nuclear power stations. The final repository is situated in underground rock caverns close to the Forsmark nuclear power plant. The rock caverns have been excavated to a depth of more than 50 m beneath the Baltic Sea floor. LLW is compacted into bales or packaged in metal drums or cases that can be transported in standard freight containers. Radioactive materials used in other sectors such as hospitals are collected and packaged at Studsvik and later deposited in the deep repository. ILW is mixed with cement or bitumen and cast in cement or steel boxes or metal drums. The final repository has different chambers for different kinds of waste. The environmental impact of the repository is negligible. Because Sweden's nuclear power plants and the SKB facilities all are located on the coast, all the waste transport can be conducted by sea. The costs of managing and disposing of Sweden's nuclear waste are small compared to the price of electricity

  14. Korean working towards low and intermediate level waste volume reduction

    Myung-Jae Song; Jong-Kil Park

    2001-01-01

    The safe management of radioactive waste is a national task required for sustainable generation of nuclear power and for energy self-reliance. This paper describes the results, efforts, and prospects for the safe management of radioactive wastes having been performed by the Nuclear Environment Technology Institute (NETEC) of the Korean Electric Power Corporation (KEPCO). Firstly, KEPCO's efforts and results for waste volume reduction are summarized to show how the number of waste drums generated per reactor-year could be reduced by about 60% during the last 10 years. Secondly, a new treatment technology, a technology for low and intermediate level waste (LILW) vitrification, was introduced to prospect how the technology reduces the waste volume and increases the inherent safety for LILW disposal. It is expected that the vitrification technology will contribute not only to reduce LILW volume to around 1/14 ∼ 1/32 but also to change the 'Not In My Back Yard' (NIMBY) syndrome to the 'Please In My Front Yard' (PIMFY) attitude of local communities/residents for LILW disposal. (author)

  15. Improved cement solidification of low and intermediate level radioactive wastes

    1993-01-01

    Cementation was the first and is still the most widely applied technique for the conditioning of low and intermediate level radioactive wastes. Compared with other solidification techniques, cementation is relatively simple and inexpensive. However, the quality of the final cemented waste forms depends very much on the composition of the waste and the type of cement used. Different kinds of cement are used for different kinds of waste and the compatibility of a specific waste with a specific cement type should always be carefully evaluated. Cementation technology is continuously being developed in order to improve the characteristics of cemented waste in accordance with the increasing requirements for quality of the final solidified waste. Various kinds of additives and chemicals are used to improve the cemented waste forms in order to meet all safety requirements. This report is meant mainly for engineers and designers, to provide an explanation of the chemistry of cementation systems and to facilitate the choice of solidification agents and processing equipment. It reviews recent developments in cementation technology for improving the quality of cemented waste forms and provides a brief description of the various cement solidification processes in use. Refs, figs and tabs

  16. Low and intermediate level disposal in Spain (El Cabril Facility)

    Zuloaga, P.

    1997-01-01

    El Cabril disposal facility is located in Southern Spain and was commissioned in October 1992. The main objective of this facility is the disposal of all low- and intermediate-level waste produced in Spain in a disposal system (Figure 1) consisting of concrete overpacks placed in concrete vaults. A drain control system exists in inspection galleries constructed beneath the disposal vaults. The facility also includes : 1) A treatment and conditioning shop (with incineration, non-NPP wastes segregation and conditioning, drum transfer into overpacks, supercompaction, liquid waste collection, and grout preparation and injection) 2) A waste form characterisation laboratory with means for non-destructive radiological characterisation and for destructive tests on the waste forms (specimens extractions, unskinning of drums, mechanical strength, leaching tests on specimens and full size packages) 3) A fabrication shop for overpacks construction 4) Auxiliary systems and buildings in support of operation, maintenance and surveillance of the facility. The paper deals with the design, the operating experience of the facility, the waste packages characterisation and acceptance practice and the reception and transport of the wastes from the producers to facilities. (author). 11 figs

  17. Acceptability of a low and intermediate level radioactive waste repository

    Zeleznik, N.; Polic, M.

    2000-01-01

    Siting of a radioactive waste repository, even for the waste of low and intermediate level (LILW) radioactivity, presents a great problem in almost every country that produces such waste. The main problem is not a technical one, but socio-psychological, namely the acceptability of this kind of repository. In general, people are opposed to any such kind of facility in their vicinity (NIMBY). In this study we try to establish the factors that influence people's behavior regarding the construction of a radioactive waste repository in their local community, with the use of Ajzen's model of planned behavior. Two different scenarios about the construction of a radioactive waste repository in their community, together with a set of questions were presented to participants from different schools. Data from the survey were analysed by multivariate methods, and a model of relevant behaviour was proposed. From the results it can be seen that different approaches to local community participation in site selection process slightly influence people's attitudes towards the LILW repository, while significant differences in answers were found in the responses which depend on participants' knowledge. Therefore the RAO Agency will further intensify preparation of the relevant communication plan and start with its implementation to support LILW repository site selection process, which will also include educational programme. (author)

  18. Moessbauer investigations of itmid

    Mrayed, Y S; Ellid, M S; Fallagh, F A [Physics and material Science Department, Tajoura Nuclear Research Center, Tripoli, (Libyan Arab Jamahiriya)

    1997-12-31

    A sample of itmid available commercially was obtained and investigated using{sup 57} Fe Moessbauer spectroscopy, atomic absorption, X-ray fluorescence. The Moessbauer spectra showed the presence hematite (alpha-Fe{sub 2} O{sub 3}), goethite (alpha-FeOOH), and a third phase which has a six-line spectrum with the following parameters : Isomer shift (gamma= 0.52 mm/s), magnetic field (H=290 kOe). After conducting a series of reduction and calcination to the itmid sample and with the aid of atomic absorption and X-ray fluorescence results the third phase was identified as the iron sulfide compound FeS. 3 figs., 3 tabs.

  19. A Moessbauer effect spectrometer

    Fayek, M.K.; Abbas, Y.M.; Bahgat, A.A.

    1983-01-01

    A Moessbauer effect spectrometer of Harwell type is installed and put in operation. The driving system is of a constant acceleration mode with a velocity range 40mm/sec. and associated to a 1024 multichannel analyser working in a multiscalar time mode. The gamma ray sources are 50 mCi Co 57 in Pd and 20 mCi Snsup(119m) in Ba Sn(O) 3 . Measurements are taken with the source kept at room temperature, while the absorber can be maintained at various temperatures. Gamma ray resonance spectra of different standard samples are obtained. Zero velocity and magnetic field calibration curves are deduced. Examples of some Moessbauer spectra for running investigated materials with a comprehensive general description are also given

  20. Moessbauer studies of malaria

    Bauminger, E.R.; Ofer, S.; Ginsburg, H.; Yayon, A.

    1983-01-01

    Moessbauer studies of rat and human erythrocytes infected by malarial parasites have been carried out. Different parameters of the pigment iron were obtained in human and rat infected red blood cells. No difference was found between the parameters obtained in rat erythrocytes infected by drug sensitive and drug resistant strains of P. berghei, both before and after the treatment with chloroquine. The pigment was shown to contain a trivalent, high spin iron compound, which is different from hematin. (Auth.)

  1. Safe dry storage of intermediate-level waste at CRL

    Chiu, A.; Sanderson, T.; Lian, J.

    2011-01-01

    Ongoing operations at Atomic Energy of Canada Limited's (AECL) Chalk River Laboratories (CRL) generate High-, Intermediate- and Low-Level Waste (HLW, ILW and LLW) that will require safe storage for several decades until a long-term management facility is available. This waste is stored in below grade concrete structures (i.e. tile holes or bunkers) or the above-ground Shielded Modular Above Ground Storage (SMAGS) facility depending on the thermal and shielding requirements of the particular waste package. Existing facilities are reaching their capacity and alternate storage is required for the future storage of this radioactive material. To this end, work has been undertaken at CRL to design, license, construct and commission the next generation of waste management facilities. This paper provides a brief overview of the existing radioactive-waste management facilities used at CRL and focuses on the essential requirements and issues to be considered in designing a new waste storage facility. Fundamentally, there are four general requirements for a new storage facility to dry store dry non-fissile ILW. They are the need to provide: (1) containment, (2) shielding, (3) decay heat removal, and (4) ability to retrieve the waste for eventual placement in an appropriate long-term management facility. Additionally, consideration must be given to interfacing existing waste generating facilities with the new storage facility. The new facilities will be designed to accept waste for 40 years followed by 60 years of passive storage for a facility lifespan of 100 years. The design should be modular and constructed in phases, each designed to accept ten years of waste. This strategy will allow for modifications to subsequent modules to account for changes in waste characteristics and generation rates. Two design concepts currently under consideration are discussed. (author)

  2. Treatment and conditioning of metallic intermediate level waste

    Lidar, Per; Larsson, Arne; Huutoniemi, Tommi; Blank, Eva; Elfwing, Mattias

    2014-01-01

    In 2011 SKB started an R and D program for evaluating different disposal concepts for LL-LILW. The purpose was to develop alternative repository concepts and conditioning methods for LL-LILW and to evaluate and compare them from a range of parameters. The goal is to present a comparison between identified repository concepts by 2013. The material should be of such a quality that SKB can make decisions of which concepts that are to be further investigated in a safety analysis. As a part of the R and D program for the LL-LILW disposal facility, Studsvik was assigned to investigate whether melting of metallic LL-LILW is technically feasible and, if so, what the requirements are to build and operate such a facility. Specific concern was given to the following metallic components: - Core components and reactor internals from both boiling water reactors (BWRs) and pressurized water reactors (PWRs). - Reactor pressure vessels from PWRs. The paper presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the Studsvik authors' experience in operating a low level waste melting facility, their conclusion is presented in the paper, considering cost of constructing and operating such a facility, in conjunction with the radio-logical risks associated with operation and the benefits to disposal and long term safety. Studsvik also investigated alternative techniques for embedding of metallic ILW components. Embedding of radioactive metallic ILW components protects the component from corrosion and leakage of radionuclides from repository to biosphere can thereby be both delayed and decreased. Conditioning by embedding has

  3. Storage for low-level and intermediate-level radioactive wastes

    1992-11-01

    The objective of this report was to assess whether three nominated sites in Norway for underground storage of low-level and intermediate-level radioactive wastes would comply with safety standards and applicable laws and regulations. The site selection criteria are described and the report evaluates the technical, environmental and socio-economic suitability of the different sites. The site selection process eliminated two of the nominated sites, whereas one site was singled out. 28 refs., 14 figs., 10 tabs

  4. Advances in Moessbauer data analysis

    Souza, Paulo A. de

    1998-01-01

    The whole Moessbauer community generates a huge amount of data in several fields of human knowledge since the first publication of Rudolf Moessbauer. Interlaboratory measurements of the same substance may result in minor differences in the Moessbauer Parameters (MP) of isomer shift, quadrupole splitting and internal magnetic field. Therefore, a conventional data bank of published MP will be of limited help in identification of substances. Data bank search for exact information became incapable to differentiate the values of Moessbauer parameters within the experimental errors (e.g., IS = 0.22 mm/s from IS = 0.23 mm/s), but physically both values may be considered the same. An artificial neural network (ANN) is able to identify a substance and its crystalline structure from measured MP, and its slight variations do not represent an obstacle for the ANN identification. A barrier to the popularization of Moessbauer spectroscopy as an analytical technique is the absence of a full automated equipment, since the analysis of a Moessbauer spectrum normally is time-consuming and requires a specialist. In this work, the fitting process of a Moessbauer spectrum was completely automated through the use of genetic algorithms and fuzzy logic. Both software and hardware systems were implemented turning out to be a fully automated Moessbauer data analysis system. The developed system will be presented

  5. Teaching New Keynesian Open Economy Macroeconomics at the Intermediate Level

    Bofinger, Peter; Mayer, Eric; Wollmershauser, Timo

    2009-01-01

    For the open economy, the workhorse model in intermediate textbooks still is the Mundell-Fleming model, which basically extends the investment and savings, liquidity preference and money supply (IS-LM) model to open economy problems. The authors present a simple New Keynesian model of the open economy that introduces open economy considerations…

  6. A Moessbauer study on the photolysis of potassium trisoxalatoferrate(III) in solid and solutions

    Sato, H.; Tominaga, T.

    1977-01-01

    The photolysis of potassium trisoxalatoferrate(III) in solid and aqueous solutions was studied by Moessbauer spectroscopy. A ferrous species was mainly detected as an intermediate product in the photoirradiated solutions. A tentative mechanism was proposed for the overall reactions in and after the photolysis of this compound. The Moessbauer spectra were measured with a Hitachi AA-40 or Shimadzu MEG-2 Moessbauer spectrometer against Co-57 in copper foil. Acrylic holders (32 mm in diameter) were used for measurements of solutions: the irradiated solution was quickly frozen before measurement by adding it dropwise into the acrylic holder which had been cooled with liquid nitrogen or dry-ice. (T.I.)

  7. Progress on the national low level radioactive waste repository and national intermediate level waste store

    Perkins, C.

    2001-01-01

    Over the last few years, significant progress has been made towards siting national, purpose-built facilities for Australian radioactive waste. In 2001, after an eight year search, a preferred site and two alternatives were identified in central-north South Australia for a near-surface repository for Australian low level (low level and short-lived intermediate level) radioactive waste. Site 52a at Everts Field West on the Woomera Prohibited Area was selected as the preferred site as it performs best against the selection criteria, particularly with respect to geology, ground water, transport and security. Two alternative sites, Site 45a and Site 40a, east of the Woomera-Roxby Downs Road, were also found to be highly suitable for the siting of the national repository. A project has commenced to site a national store for intermediate (long-lived intermediate level) radioactive waste on Commonwealth land for waste produced by Commonwealth agencies. Public input has been sought on relevant selection criteria

  8. Deep geologic repository for low and intermediate radioactive level waste in Canada

    Liu Jianqin; Li Honghui; Sun Qinghong; Yang Zhongtian

    2012-01-01

    Ontario Power Generation (OPG) is undergoing a project for the long-term management of low and intermediate level waste (LILW)-a deep geologic repository (DGR) project for low and intermediate level waste. The waste source term disposed, geologic setting, repository layout and operation, and safety assessment are discussed. It is expected to provide reference for disposal of low and intermediate level waste that contain the higher concentration of long-lived radionuclides in China. (authors)

  9. Ghost lines in Moessbauer relaxation spectra

    Price, D.C.

    1985-01-01

    The appearance in Moessbauer relaxation spectra of 'ghost' lines, which are narrow lines that do not correspond to transitions between real hyperfine energy levels of the resonant system, is examined. It is shown that in many cases of interest, the appearance of these 'ghost' lines can be interpreted in terms of the relaxational averaging of one or more of the static interactions of the ion. (orig.)

  10. Moessbauer Studies of Implanted Impurities in Solids

    2002-01-01

    Moessbauer studies were performed on implanted radioactive impurities in semiconductors and metals. Radioactive isotopes (from the ISOLDE facility) decaying to a Moessbauer isotope were utilized to investigate electronic and vibrational properties of impurities and impurity-defect structures. This information is inferred from the measured impurity hyperfine interactions and Debye-Waller factor. In semiconductors isoelectronic, shallow and deep level impurities have been implanted. Complex impurity defects have been produced by the implantation process (correlated damage) or by recoil effects from the nuclear decay in both semiconductors and metals. Annealing mechanisms of the defects have been studied. \\\\ \\\\ In silicon amorphised implanted layers have been recrystallized epitaxially by rapid-thermal-annealing techniques yielding highly supersaturated, electrically-active donor concentrations. Their dissolution and migration mechanisms have been investigated in detail. The electronic configuration of Sb donors...

  11. Moessbauer effect and vacancy diffusion

    Gunther, L.

    1976-01-01

    A dynamical theory of vacancy diffusion which was motivated by the need to explain recent experimental results for the Moessbauer spectra of Fe in Cu, Fe in Au and Fe in Al is presented. Diffusion in these systems is dominated by the vacancy mechanism, which involves strong correlations between successive jumps. The theory developed by Singwi and Sjoelander for the Moessbauer spectrum of a diffusing nucleus is therefore not applicable. The inverse of the normalized Moessbauer spectrum evaluated at zero frequency is introduced as a useful means of comparing experimental with theoretical spectral widths

  12. Intermediate-level crossings of a first-passage path

    Bhat, Uttam; Redner, S

    2015-01-01

    We investigate some simple and surprising properties of a one-dimensional Brownian trajectory with diffusion coefficient D that starts at the origin and: (i) is at X at time T, or (ii) first reaches X at time T. We determine the most likely location of the first-passage trajectory from (0, 0) to (X, T) and its distribution at any intermediate time t < T. A first-passage path typically starts out by being repelled from its final location when X 2 /DT ≪ 1. We also determine the distribution of times when the trajectory first crosses and last crosses an arbitrary intermediate position x < X. The distribution of first-crossing times may be unimodal or bimodal, depending on whether X 2 /DT ≪ 1 or X 2 /DT ≫ 1. The form of the first-crossing probability in the bimodal regime is qualitatively similar to, but more singular than, the well-known arcsine law. (paper)

  13. Low- and intermediate-level waste repository-induced effects

    Leupin, O.X.; Marschall, P.; Johnson, L.; Cloet, V.; Schneider, J. [National Cooperative for the Disposal of Radioactive Waste (NAGRA), Wettingen (Switzerland); Smith, P. [Safety Assessment Management Ltd, Henley-On-Thames, Oxfordshire (United Kingdom); Savage, D. [Savage Earth Associates Ltd, Bournemouth, Dorset (United Kingdom); Senger, R. [Intera Inc., Ennetbaden (Switzerland)

    2016-10-15

    This status report aims at describing and assessing the interactions of the radioactive waste emplaced in a low- and intermediate level waste (L/ILW) repository with the engineered materials and the Opalinus Clay host rock. The Opalinus Clay has a thickness of about 100 m in the proposed siting regions. Among other things the results are used to steer the RD and D programme of NAGRA. The repository-induced effects considered in this report are of the following broad types: - Thermal effects: i.e. effects arising principally from the heat generated by the waste and the setting of cement. - Rock-mechanical effects: i.e. effects arising from the mechanical disturbance to the rock caused by the excavation of the emplacement caverns and other underground structures. - Hydraulic and gas-related effects: i.e. the effects of repository resaturation and of gas generation, e.g. due to the corrosion of metals within the repository, on the host rock and engineered barriers. - Chemical effects: i.e. chemical interactions between the waste, the engineered materials and the host rock. Deep geological repositories are designed to avoid or mitigate the impact of potentially detrimental repository-induced effects on long-term safety. For the repository under consideration in the present report, an assessment of those repository-induced effects that remain shows that detrimental chemical and mechanical impacts are largely confined to the rock adjacent to the excavations, thermal impacts are minimal and gas effects can be mitigated by appropriate design measures to reduce gas production and provide pathways for gas transport that limit gas pressure build-up (engineered gas transport system, or EGTS). Specific measures that are part of the current reference design are discussed in relation to their significance with respect to repository-induced effects. The disposal system described in this report provides a system of passive barriers with multiple safety functions. The disposal

  14. Low- and intermediate-level waste repository-induced effects

    Leupin, O.X.; Marschall, P.; Johnson, L.; Cloet, V.; Schneider, J.; Smith, P.; Savage, D.; Senger, R.

    2016-10-01

    This status report aims at describing and assessing the interactions of the radioactive waste emplaced in a low- and intermediate level waste (L/ILW) repository with the engineered materials and the Opalinus Clay host rock. The Opalinus Clay has a thickness of about 100 m in the proposed siting regions. Among other things the results are used to steer the RD and D programme of NAGRA. The repository-induced effects considered in this report are of the following broad types: - Thermal effects: i.e. effects arising principally from the heat generated by the waste and the setting of cement. - Rock-mechanical effects: i.e. effects arising from the mechanical disturbance to the rock caused by the excavation of the emplacement caverns and other underground structures. - Hydraulic and gas-related effects: i.e. the effects of repository resaturation and of gas generation, e.g. due to the corrosion of metals within the repository, on the host rock and engineered barriers. - Chemical effects: i.e. chemical interactions between the waste, the engineered materials and the host rock. Deep geological repositories are designed to avoid or mitigate the impact of potentially detrimental repository-induced effects on long-term safety. For the repository under consideration in the present report, an assessment of those repository-induced effects that remain shows that detrimental chemical and mechanical impacts are largely confined to the rock adjacent to the excavations, thermal impacts are minimal and gas effects can be mitigated by appropriate design measures to reduce gas production and provide pathways for gas transport that limit gas pressure build-up (engineered gas transport system, or EGTS). Specific measures that are part of the current reference design are discussed in relation to their significance with respect to repository-induced effects. The disposal system described in this report provides a system of passive barriers with multiple safety functions. The disposal

  15. Radiological protection and the selection of management strategies for intermediate level wastes

    Hill, M.D.; Webb, G.A.M.

    1982-01-01

    This paper describes the steps involved in selecting management systems and an overall management strategy for intermediate level solid radioactive wastes. The radiological protection inputs to intermediate level waste management decisions are discussed, together with the results of preliminary radiological assessments of disposal options. Areas where further work is required are identified. (author)

  16. Moessbauer Spectroscopy in Materials Science

    2006-01-01

    The publication in electronic form has been set up as proceedings of the conference dealing with applications of the Moessbauer spectroscopy in material science. Twenty-three abstracts and twenty-two presentations are included.

  17. A versatile Moessbauer analysis program

    Jernberg, P.; Sundqvist, T.

    1983-06-01

    MDA - Moessbauer Data Analysis, is a user oriented computer program, aiming to simulate a Moessbauer transmission spectrum, given by a set of parameters, and compare it with experimental data. The calculation considers a number of experimental situations and the comparisons can be made by least squares sums or by plotting the simulated and the measured spectrum. A fitting routine, minimizing the least squares sum, can be used to find the parameters characterizing the measured spectrum.(author)

  18. Moessbauer experiments, ch. 1

    Maring, K.W.

    1977-01-01

    The magnetic properties of iron base alloys have been investigated as a function of the concentrations of the sp-elements Al, Si, Ga, Ge, As, Sn, and Sb. An extensive description of the Moessbauer Effect Spectroscopy (MES) technique is given. The results of MES experiments at room temperature for FeX alloys (X stands for one of the sp-elements) and impurity concentrations of 1, 3 and 5 a/o are presented. Through temperature dependant measurements the hyperfine fields H ((m,n)T) at iron nuclei in different surroundings are obtained. The change of the Curie temperature of the various dilute iron-base alloys, with respect to pure iron, as a function of the impurity concentration is investigated. Average magnetic hyperfine fields and isomer shifts measured at 119 Sn nuclei in Fe 119 Sn are discussed

  19. Intermediate bands versus levels in non-radiative recombination

    Luque, Antonio; Marti, Antonio; Antolin, Elisa; Tablero, Cesar

    2006-01-01

    There is a practical interest in developing semiconductors with levels situated within their band gap while preventing the non-radiative recombination that these levels promote. In this paper, the physical causes of this non-radiative recombination are analyzed and the increase in the density of the impurities responsible for the mid-gap levels to the point of forming bands is suggested as the means of suppressing the recombination. Simple models supporting this recommendation and helping in its quantification are presented

  20. The history of the Moessbauer effect

    Miglierini, M

    2003-01-01

    The background of the discovery of the Moessbauer effect and the development of Moessbauer spectrometry as an analytical technique are highlighted. The basic principles and instrumentation, application fields, and trends of future progress and outlined and discussed

  1. Moessbauer effect technique in mineral science

    Raclavsky, K.; Egiazarov, B.G.

    1975-01-01

    A survey is presented of literature devoted to the application of the Moessbauer effect in practical work. Significant problems are pointed to of applying Moessbauer spectroscopy in specific fields. An extensive list of references is annexed. (L.O.)

  2. An intermediate level of abstraction for computational systems chemistry

    Andersen, Jakob L.; Flamm, Christoph; Merkle, Daniel

    2017-01-01

    system, well grounded in category theory, at the right level of abstraction for the analysis of large and complex reaction networks. An extension of the basic formalism into the realm of integer hyperflows allows for the identification of complex reaction patterns, such as autocatalysis, in large...

  3. Intermediate-Level Foreign Language Courses for BBA Students.

    Ortuno, Manuel J.; Uber, David M.

    Following the early success of its inclusion of languages in the master's-level business administration curriculum, Baylor University began to emphasize foreign language study more heavily in its undergraduate business administration program. The revised program, to be fully implemented in 1989, encourages students to choose 11 hours of language…

  4. Low- and intermediate-level waste management practices in Japan

    Tsuchiya, M.

    1982-01-01

    At present, disposal of low-level radioactive wastes is yet to be carried out in Japan. Liquid wastes, except for the diluted discharge of very low-level waste into the environment, are mostly solidified with cement or bitumen to be packed in 200 litre drums and put in storage. Solid wastes, on the other hand, are mostly put into in 200 litre drums, some of them being incinerated beforehand. Efforts are being made to develop technology for reducing the production of wastes. Regarding sea disposal, a test dumping program has been forestalled by the opposition of South Pacific islanders, but we are endeavoring to promote their understandings on this matter. Regarding land disposal, first we are going to start centralized storage, then shift to underground disposal

  5. Status and advice of the low and intermediate level radioactive waste disposal sites in China

    Teng Keyan; Lu Caixia

    2012-01-01

    With the rapid development of nuclear power industry in China, as well as the decommissioning of the nuclear facilities, and the process of radioactive waste management, a mount of the low and intermediate level radioactive solid wastes will increase rapidly. How to dispose the low and intermediate level radioactive solid wastes, that not only related to Chinese nuclear energy and nuclear technology with sustainable development, but also related to the public health, environment safety. According to Chinese « long-term development plan of nuclear power (2005- 2020) », when construct the nuclear power, should simultaneous consider the sites that dispose the low and intermediate level radioactive waste, In order to adapt to the needs that dispose the increasing low and intermediate level radioactive waste with development of nuclear power. In the future, all countries are facing the enormous challenge of nuclear waste disposal. (authors)

  6. Portable and Automatic Moessbauer Analysis

    Souza, P. A. de; Garg, V. K.; Klingelhoefer, G.; Gellert, R.; Guetlich, P.

    2002-01-01

    A portable Moessbauer spectrometer, developed for extraterrestrial applications, opens up new industrial applications of MBS. But for industrial applications, an available tool for fast data analysis is also required, and it should be easy to handle. The analysis of Moessbauer spectra and their parameters is a barrier for the popularity of this wide-applicable spectroscopic technique in industry. Based on experience, the analysis of a Moessbauer spectrum is time-consuming and requires the dedication of a specialist. However, the analysis of Moessbauer spectra, from the fitting to the identification of the sample phases, can be faster using by genetic algorithms, fuzzy logic and artificial neural networks. Industrial applications are very specific ones and the data analysis can be performed using these algorithms. In combination with an automatic analysis, the Moessbauer spectrometer can be used as a probe instrument which covers the main industrial needs for an on-line monitoring of its products, processes and case studies. Some of these real industrial applications will be discussed.

  7. Hyperfine interactions by Moessbauer effect

    Constantinescu, S.

    1980-01-01

    Moessbauer spectroscopy has been used to investigate hyperfine interactions in materials endowed with complex electromagnetic crystallographic structures. Such structures (Me 3 B 7 O 13 X boracite-type systems, for instance), equally interesting from both scientific and applications viewpoint, are drawing a special attention lately on account of their being examined by means of increasingly refined experimental techniques. In view of the wide prospects of using these materials in various practical fields, this thesis counts among the studies aiming to ameliorate the methods of processing and determining the Moessbauer spectra parameters, characterized by complex hyperfine interactions, as well as among the studies of electric, magnetic and crystallographic investigation of the Moessbauer nucleus neighbourhood, in boracite-type structures. (author)

  8. The Moessbauer community in the USA

    Stevens, J. G.; Khasanov, A. M.; Hall, N. F.; Khasanova, I. A.

    2006-01-01

    Scientists in the United States assumed major roles in developing the Moessbauer community during its early years. However, since the termination of the Moessbauer Effect Methodology meetings in 1976, there has been little in the way of regular Moessbauer meetings in the United States. Nevertheless, there is an active United States Moessbauer community, as noted by the number of annual publications - 156 in 2004. In recent decades, attendance of Moessbauer researchers from the United States at the International Conferences on the Applications of the Moessbauer Effect (ICAME) has been far below what would be expected from the number of contributions in the Moessbauer literature. Attempts have been made, unsuccessfully, to arrange for regular Moessbauer meetings. Models for possible future Moessbauer meetings of US scientists are discussed, including a regular biannual meeting, and another being a virtual Moessbauer conference. Also discussed are other models to maintaining an active Moessbauer community in the United States, making use of information technologies that are available to us along with other resources we can use.

  9. Moessbauer effect and its applications

    Butt, N.M.; Arshad, M.

    1995-01-01

    This paper presents the basic concepts of Moessbauer effect. The provision of extremely high energy resolution, 1 part in 10/sp 12/, is the remarkable feature of this effects. This feature can be used to solve various problems where small changes in energy are involved. This effect has been applied in various disciplines of science like astrophysics, archaeology, biology, corrosion, amorphous alloys, chemistry, metallurgy, solid state physics, magnetism, superconductivity etc. A brief description of Moessbauer effect along with some typical examples are presented to demonstrate the importance and power of this effect in solving problems in these areas. (author)

  10. Canadian experiences in characterizing two low-level and intermediate-level radioactive waste management sites

    Heystee, R.J.; Rao, P.K.M.

    1984-02-01

    Low-level waste (LLW) and intermediate-level reactor waste (ILW) arise in Canada from the operation of nuclear power reactors for the generation of electricity and from the operation of reactors for nuclear research and development as well as for the production of separated radioisotopes. The majority of this waste is currently being safely managed at two sites in the Province of Ontario: (1) Chalk River Nuclear Laboratories, and (2) Ontario Hydro's Bruce Nuclear Power Development Radioactive Waste Operations Site 2. Although these storage facilities can safely manage the waste for a long period of time, there are advantages in disposal of the LLW and ILW. The design of the disposal facilities and the assessment of long-term performance will require that the hydrologic and geologic data be gathered for a potential disposal site. Past site characterization programs at the two aforementioned waste storage sites have produced information which will be useful to future disposal studies in similar geologic materials. The assessment of long-term performance will require that predictions be made regarding the potential subsurface migration of radionuclides. However there still remain many uncertainties regarding the chemical and physical processes which affect radionuclide mobility and concentrations, in particular hydrodynamic dispersion, geochemical reactions, and transport through fractured media. These uncertainties have to be borne in mind when conducting the performance assessments and adequate conservatism must be included to account for the uncertainties. (author)

  11. Conditioning of intermediate-level waste at Forschungszentrum Juelich GmbH

    Krumbach, H.

    2003-01-01

    This contribution to the group of low-level, intermediate, mixed and hazardous waste describes the conditioning of intermediate-level mixed waste (dose rate above 10 mSv/h at the surface) from Research Centre Juelich (FZJ). Conditioning of the waste by supercompaction is performed at Research Centre Karlsruhe (FZK). The waste described is radioactive waste arising from research at Juelich. This waste includes specimens and objects from irradiation experiments in the research reactors Merlin (FRJ-1) and Dido (FRJ-2) at FZJ. In principle, radioactive waste at Forschungszentrum Juelich GmbH is differentiated by the surface dose rate at the waste package. Up to a surface dose rate of 10 mSv/h, the waste is regarded as low-level. The radioactive waste described here has a surface dose rate above 10 mSv/h. Waste up to 10 mSv/h is conditioned at the Juelich site according to different conditioning methods. The intermediate-level waste can only be conditioned by supercompaction in the processing facility for intermediate-level waste from plant operation at Research Centre Karlsruhe. Research Centre Juelich also uses this waste cell to condition its intermediate-level waste from plant operation. (orig.)

  12. AERE contracts with DoE on the treatment and disposal of intermediate level wastes

    Partridge, B.A.

    1984-06-01

    This document reports work carried out in 1983/84 under 10 contracts between DoE and AERE on the treatment and disposal of intermediate level wastes. Individual summaries are provided for each contract report within the document, under the headings: comparative evaluation of α and βγ irradiated medium level waste forms; modelling and characterisation of intermediate level waste forms based on polymers; optimisation of processing parameters for polymer and bitumen modified cements; ceramic waste forms; radionuclide release during leaching; ion exchange processes; electrical processes for the treatment of medium active liquid wastes; fast reactor fuel element cladding; dissolver residues; flowsheeting/systems study. (U.K.)

  13. Moessbauer effect studies with actinides

    Stone, J.A.

    1966-01-01

    Moessbauer resonance studies in the actinide elements offer a new technique for measuring solid-state properties to a region of the periodic chart where such information is relatively sparse. It is well known that the actinides, the elements with atomic numbers from 90 to 103, form a transition series due to filling of the 5f electron shell, analogous to the rare-earth series in which the 4f shell is filled. Like the rare earths, the actinide metals and compounds are expected to exhibit a variety of interesting magnetic properties, but, unlike the rare earths, there have been few studies of the magnetic behaviour of actinides, and these properties are largely unknown. The chemical properties of the actinides have been studied somewhat more extensively, and, in contrast to the rare earths, form a multiplicity of stable valence states, especially in the lighter members of the series. It is just these properties, magnetic and chemical, for which the Moessbauer effect is a valuable probe, sensitive to the magnetic and electric environment of an atom. The rare-earth series has been a particularly fruitful region in terms of the number of elements which have been shown to exhibit the Moessbauer effect, and for this reason the exploitation of the Moessbauer effect to yield new solid-state and chemical information on the rare earths is a highly active field of research today. There is every reason to believe that the actinides can be similarly studied by the Moessbauer effect. 43 refs, 6 figs, 4 tabs

  14. Feasibility of large volume casting cementation process for intermediate level radioactive waste

    Chen Zhuying; Chen Baisong; Zeng Jishu; Yu Chengze

    1988-01-01

    The recent tendency of radioactive waste treatment and disposal both in China and abroad is reviewed. The feasibility of the large volume casting cementation process for treating and disposing the intermediate level radioactive waste from spent fuel reprocessing plant in shallow land is assessed on the basis of the analyses of the experimental results (such as formulation study, solidified radioactive waste properties measurement ect.). It can be concluded large volume casting cementation process is a promising, safe and economic process. It is feasible to dispose the intermediate level radioactive waste from reprocessing plant it the disposal site chosen has resonable geological and geographical conditions and some additional effective protection means are taken

  15. Application of remote sensing technique to site selection for low and intermediate level radioactive waste

    Chen Zhangru; Jin Yuanxin; Liu Yuemiao; Hou Dewen

    2001-01-01

    Based on the relative criteria of selection of disposal site for low and intermediate level radioactive waste, the social-economic conditions, landform, morphologic properties, regional geological stability, hydrogeological and engineering geological characters of adjacent area of Anhui, Zhejiang and Jiangsu provinces were investigated. The geological interpretation of thematic mapper images, field reconnaissance and data analysis were conducted during the research work. The results show that three areas in the west part of Zhejiang Province were recommended as potential site for disposal of low and intermediate level radioactive waste. They are Bajiaotang area, Tiebanchong area and Changxing-Guangde-Anji nabes

  16. Brazilian low and intermediate level radioactive waste disposal and environmental conservation areas

    Uemura, George; Cuccia, Valeria

    2013-01-01

    Low and intermediate level radioactive waste should be disposed off in proper disposal facilities. These facilities must include unoccupied areas as protection barriers, also called buffer zone. Besides that, Brazilian environmental laws require that certain enterprises must preserve part of their area for environmental conservation. The future Brazilian low and intermediate level waste repository (RBMN) might be classified as such enterprise. This paper presents and discusses the main Brazilian legal framework concerning different types of conservation areas that are allowed and which of them could be applied to the buffer zones of RBMN. The possibility of creating a plant repository in the buffer zone is also discussed. (author)

  17. The Moessbauer effect data center: A report

    Stevens, J.G.

    1990-01-01

    The Moessbauer Effect Data Center is unique in its operation and the kind of information services that it provides. It is probably the only user-supported information center in the basic sciences. This has been primarily possible due to the broad support and encouragement the center receives from the international Moessbauer community. This report also discusses the demographics of the Moessbauer community: identifying such items as the most active areas of research in Moessbauer Spectroscopy, where is this research being done and who is doing it. Also, examined is where Moessbauer research investigations are being published. BITNET and other forms of electronic mail are being widely used in the scientific community. This is also the case in the Moessbauer community. Directories and list-servers are being established. (orig.)

  18. Moessbauer neutrinos in quantum mechanics and quantum field theory

    Kopp, Joachim

    2009-01-01

    We demonstrate the correspondence between quantum mechanical and quantum field theoretical descriptions of Moessbauer neutrino oscillations. First, we compute the combined rate Γ of Moessbauer neutrino emission, propagation, and detection in quantum field theory, treating the neutrino as an internal line of a tree level Feynman diagram. We include explicitly the effect of homogeneous line broadening due to fluctuating electromagnetic fields in the source and detector crystals and show that the resulting formula for Γ is identical to the one obtained previously [1] for the case of inhomogeneous line broadening. We then proceed to a quantum mechanical treatment of Moessbauer neutrinos and show that the oscillation, coherence, and resonance terms from the field theoretical result can be reproduced if the neutrino is described as a superposition of Lorentz-shaped wave packet with appropriately chosen energies and widths. On the other hand, the emission rate and the detection cross section, including localization and Lamb-Moessbauer terms, cannot be predicted in quantum mechanics and have to be put in by hand.

  19. Metallurgical applications of the Moessbauer effect

    Flinn, P.A.

    1975-01-01

    Recent developments and practical applications of the Moessbauer effect are reviewed. Moessbauer studies into solid solutions, phase transformations in certain alloy systems and steels, deformation-induced transformations in and corrosion of steels are discussed. Also discussed are the applications of Moessbauer spectroscopy in process metallurgy for diffusion measurements in solids and in an accurate quantitative analysis. The use of backscatter geometry is dealt with. (Z.S.)

  20. The Latin American Moessbauer research community

    Stevens, J.G.

    1994-01-01

    Interest in Moessbauer spectroscopy among the Latin American countries has increased in the last five years. Two-thirds of the published research is coming from the Moessbauer research groups in Brazil. Other Latin American countries with active Moessbauer research include Argentina, Chile, Columbia, Cuba, Mexico, Peru, and Venezuela. In recent years, the area having the most interest has been the investigation of minerals and high temperature superconductors. (orig.)

  1. Advice concerning the advantages of a reference incinerator for low-level and intermediate-level radioactive waste processing

    Luyten, G.B.

    1985-05-01

    In this report, an inventory is presented of new incinerators and flue gas filters used in low and intermediate-level radioactive waste combustion. It is argued that a 'reference equipment' for the combustion of solid and liquid low- and intermediate-level wastes best meets existing Dutch radiation protection standards. A cost-benefit analysis of such an equipment is given including annual costs of investment, capital and exploration. A separate combustion process of organic liquids and carrions is considered finally. (G.J.P.)

  2. Moessbauer effect in superconducting organosol of tin

    Dekhtyar, I.Ya.; Zhelibo, E.P.; Kushnir, B.G.; Nishchenko, M.M.; Pan, V.M.; Popov, A.G.; Khvorov, M.M.; AN Ukrainskoj SSR, Kiev. Inst. Kolloidnoj Khimii i Khimii Vody)

    1977-01-01

    Structure of disperse particles (approximately 1 μm) of tin organosols have been investigated by means of the Moessbauer effect. A considerable amount of oxides (up to 20%) in amorphous (SnO 2 ) or in metastable crystalline (SnO) states has been discovered. The observed properties of the Moessbauer spectrum of organosols are compared with measurements of their critical temperature. The effect of impurities and of other structural defects on the dynamic and superconducting properties of organosols is observed. Temperature broadening of lines and temperature variation of the Moessbauer effect value for the particle of different dimensions are in a qualitative agreement with the theory of the granular Moessbauer absorbers

  3. Probing the Natural World, Level III, Teacher's Edition: Investigating Variation. Intermediate Science Curriculum Study.

    Bonar, John R., Ed.; Hathway, James A., Ed.

    This is the teacher's edition of one of the eight units of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). This unit focuses on diversity in human populations, measurement, and data collection. Optional excursions are described for students who wish to study a topic in greater depth. An introduction describes…

  4. Probing the Natural World, Level III, Student Guide: Investigating Variation. Intermediate Science Curriculum Study.

    Bonar, John R., Ed.; Hathway, James A., Ed.

    This is the student's text of one unit of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). This unit focuses on diversity in human populations, measurement, and data collection. Numerous activities are given and optional excursions encourage students to pursue a topic in greater depth. Data tables within the…

  5. Natural analogue study for low-and-intermediate level radioactive waste shallow burial disposal

    Gu Cunli; Fan Zhiwen; Huang Yawen; Cui Anxi; Liu Xiuzheng; Zhang Jinshen

    1995-01-01

    The paper makes a comparison of low-and-intermediate level radioactive waste shallow burial disposal with Chinese ancient tombs in respects of siting, engineering structures, design principle and construction procedures. Results showed that Chinese ancient tombs are very good analogue for low-and-intermediate level radioactive waste shallow burial disposal. Long-term preservation of ancient tombs and buried objects demonstrated that low-and-intermediate level radioactive waste shallow burial disposal would be safe if suitable sites were selected, reasonable engineering structures and good backfill materials were adopted, and scientific construction procedures were followed. The paper reports for the first time the testing results of certain ancient tomb backfill materials. The results indicated that the materials have so low a permeability as 1.5 x 10 -8 cm/s , and strong adsorption to radionuclides Co and Cs with the distribution coefficients of 1.4 x 10 4 mL/g and 2.1 x 10 4 mL/g, and the retardation factors of 4.4 x 10 4 and 7.7 x 10 4 respectively. Good performance of these materials is important assurance of long-term preservation of the ancient tombs. These materials may be considered to be used as backfill materials in low-and-intermediate level radioactive shallow burial disposal. (4 figs., 10 tabs.)

  6. Norwegian work on establishing a combined storage and disposal facility for low and intermediate level waste

    International Atomic Energy Agency WATRP Review Team.

    1995-12-01

    The IAEA has, through its Waste Management Assessment and Technical Review Programme (WATRP), evaluated policies and facilities related to management of radioactive waste in Norway. It is concluded that the Himdalen site, in combination with the chosen engineering concept, can be suitable for the storage and disposal of the relatively small amounts of Norwegian low and intermediate level waste

  7. Central repository for low- and intermediate-level waste (ALMA) conceptual design, siting and safety study

    Kjellbert, N.; Haeggblom, H.; Cederstroem, M.; Lundgren, T.

    1980-07-01

    A generic design, siting and safety study of a proposed repository for low- and intermediate-level waste has been made. Special emphasis has been placed on safety characterostics. The conceptual design and the generic site, on which the study is based, are realistically chosen in accordance with present construction techniques and the existing geohydrological conditions in Sweden. (Auth.)

  8. A strategy for the improvement of the intermediate and low level radioactive waste management

    Benitez, J.C.; Salgado, M.; Jova, L.

    1996-01-01

    The work describes the surrent situation with regard to the management of intermediate and low level radioactive wastes that are generated in the country. Updated information is reffered on the quantities of stored wastes that are to be treated and conditioned at the facilities of the CPHR

  9. Establishing managerial requirements for low-and intermediate-level waste repository

    Chung, C. W.; Lee, Y. K.; Kim, H. T.; Park, W. J.; Suk, T. W.; Park, S. H.

    2004-01-01

    This paper reviews basic considerations for establishing managerial requirements on the domestic low-and intermediate-level radioactive waste repository and presents the corresponding draft requirements. The draft emphasizes their close linking with the related regulations, standards and safety assessment for the repository. It also proposes a desirable direction towards harmonizing together with the existing waste acceptance requirements for the repository

  10. Assessment of Student Achievement: Evaluation of Student Achievement at the Intermediate Level. Final Report.

    Wahlstrom, M.; And Others

    Evaluation and assessment procedures of Ontario, Canada principals and teachers at the Intermediate level (grades 7 and 8) were examined. Extensive questionnaires were returned by 134 principals and 225 teachers divided across the subject areas of English, Mathematics, Science, Languages, History, Home Economics or Shop, Arts, and Physical…

  11. Survey of stores for conditioned intermediate and low level wastes in Europe

    1985-10-01

    A survey has been conducted of eleven waste storage facilities in six countries. Wastes considered are intermediate and low level, conditioned for disposal. Civil engineering, handling facilities, container type, waste activities, doses to the public and to operators are considered. (author)

  12. The influence of organic materials on the near field of an intermediate level radioactive waste repository

    Wilkins, J.D.

    1988-01-01

    The influence of organic materials which are present in some intermediate level wastes on the chemistry of the near field of a radioactive waste repository is discussed. Particular attention is given to the possible formation of water soluble complexing agents as a result of the radiation field and chemical conditions. The present state of the research is reviewed. (author)

  13. Comparative estimates of risks arising from storage of intermediate level radioactive wastes

    Moore, D.

    1986-04-01

    Estimates are presented of risks arising from accidents occuring during storage of nine types of conditioned intermediate level waste. Additional data are introduced relating to the risks from accidents affecting raw waste, and to risks associated with the occupational doses received during normal operation of a waste store. Risks in all three categories are shown to be extremely small. (author)

  14. ESL for Hotel/Hospitality Industry. Level: Advanced Beginner/Intermediate.

    Western Suffolk County Board of Cooperative Educational Services, Northport, NY.

    This document contains 16 lesson plans for an advanced beginning and intermediate course in work-related English for non-English- or limited-English-speaking entry-level employees in the hotel and hospitality industry. Course objectives are as follows: helping participants understand and use job-specific vocabulary; receive and understand…

  15. Probing the Natural World, Level III, Student Guide: What's Up? Intermediate Science Curriculum Study.

    Bonar, John R., Ed.; Hathway, James A., Ed.

    This is the student's text of one unit of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). The chapters contain basic information about rockets, space, and principles of physics, as well as activities related to the subject and optional excursions. A section of introductory notes to the student discusses how the…

  16. Assessment of studies and researches on warehousing - High-level and intermediate-level-long-lived radioactive wastes - December 2012

    2013-01-01

    This large report first presents the approach adopted for the study and research on the warehousing of high-level and intermediate-level-long-lived radioactive wastes. It outlines how reversible storage and warehousing are complementary, discusses the lessons learned from researches performed by the CEA on long duration warehousing, presents the framework of studies and researches performed since 2006, and presents the scientific and technical content of studies and researches (warehousing need analysis, search for technical options providing complementarity with storage, extension or creation of warehousing installations). The second part addresses high-level and intermediate-level-long-lived radioactive waste parcels, indicates their origins and quantities. The third part proposes an analysis of warehousing capacities: existing capacities, French industrial experience in waste parcel warehousing, foreign experience in waste warehousing. The fourth part addresses reversible storage in deep geological formation: storage safety functions, storage reversibility, storage parcels, storage architecture, chronicle draft. The fifth part proposes an inventory of warehousing needs in terms of additional capacities for the both types of wastes (high-level, and intermediate-level-long-lived), and discusses warehousing functionalities and safety objectives. The sixth and seventh parts propose a detailed overview of design options for warehousing installations, respectively for high-level and for intermediate-level-long-lived waste parcels: main technical issues, feasibility studies of different concepts or architecture shapes, results of previous studies and introduction to studies performed since 2011, possible evolutions of the HA1, HA2 and MAVL concepts. The eighth chapter reports a phenomenological analysis of warehousing and the optimisation of material selection and construction arrangements. The last part discusses the application of researches to the extension of the

  17. Practices and developments in the management of low and intermediate level radioactive waste in Sweden

    Hultgren, Aa.

    1983-06-01

    In the Swedish nuclear power program ten reactors are in operation and two more under construction. About 100000 m 3 of low and intermediate level radioactive waste will be produced from the operation of these reactors until the year 2010 and about 150000 m 3 from their decommissioning. All burnable radioactive wastes are sent to the Studsvik incineration plant for incineration. Spent resins are incorporated into cement or bitumen. The volume of non-combustible solid waste is reduced by compaction where possible. At the Studsvik research centre a substantial program for improved management of accumulated and future radioactive waste is at the beginning of its implementation. This includes advanced treatment and intermediate storage in a rock cavity. An R and D program on volume reduction of spent resins has reached the point of process verification and equipment design. All low and intermediate radioactive waste will be disposed in a rock cavity planned for commissioning by 1988. The paper reviews actual management experience and development efforts for low and intermediate level radioactive waste in Sweden. Contribution to the Seminar on the Management of Radioactive Waste, Taipei, Taiwan, 25-26 June, 1983. (Author)

  18. AERE contracts with DoE on the treatment and disposal of intermediate level wastes

    Partridge, B.A.

    1984-11-01

    Reports are presented on work on the following topics concerned with the treatment and disposal of intermediate-level radioactive wastes: comparative evaluation of α and β γ irradiated medium level waste forms; modelling and characterisation of intermediate level waste forms based on polymers; optimisation of processing parameters for polymer and bitumen modified cements; α damage in non-reference waste form matrix materials; leaching mechanisms and modelling; inorganic ion exchange treatment of medium active effluents; electrical processes for the treatment of medium active liquid waste; fast reactor fuel element cladding; dissolver residues; effects of radiation on the properties of cemented MTR waste forms; equilibrium leach testing of cemented MTR waste forms; radiolytic oxidation of radionuclides; immobilisation of liquid organic waste; quality control, non-conformances and corrective action. (U.K.)

  19. Aube storage centre for short-lived low- and intermediate-level wastes. Annual report 2009

    2010-06-01

    The National Radioactive Waste Management Agency (Andra), was established by the December 1991 Waste Act as a public body in charge of the long-term management of all radioactive waste, under the supervision of the Ministry of Ecology, Energy, Sustainable Development and the Sea (formerly the Ministry of Industry and the Ministry of Environment), and the Ministry of Research. The Andra operates two storage centers in the Aube region (France): the center for short-lived low- and intermediate-level wastes, and the center for very-low-level radioactive wastes. This document is the 2009 activity report of the center for short-lived low- and intermediate-level wastes. It presents a review of the activities of the center: presentation of the installations, safety and radiation protection, events or incidents, environmental monitoring, wastes management, public information, opinion of the Health and safety Committee (CHSCT)

  20. Aube storage center for short-lived low- and intermediate-level wastes. Annual report 2008

    2009-06-01

    The National Radioactive Waste Management Agency (Andra), was established by the December 1991 Waste Act as a public body in charge of the long-term management of all radioactive waste, under the supervision of the Ministry of Ecology, Energy, Sustainable Development and the Sea (formerly the Ministry of Industry and the Ministry of Environment), and the Ministry of Research. The Andra operates two storage centers in the Aube region (France): the center for short-lived low- and intermediate-level wastes, and the center for very-low-level radioactive wastes. This document is the 2008 activity report of the center for short-lived low- and intermediate-level wastes. It presents a review of the activities of the center: presentation of the installations, safety and radiation protection, events or incidents, environmental monitoring, wastes management, public information

  1. Aube storage center for short-lived low- and intermediate-level wastes. Annual report 2010

    2011-06-01

    The National Radioactive Waste Management Agency (Andra), was established by the December 1991 Waste Act as a public body in charge of the long-term management of all radioactive waste, under the supervision of the Ministry of Ecology, Energy, Sustainable Development and the Sea (formerly the Ministry of Industry and the Ministry of Environment), and the Ministry of Research. The Andra operates two storage centers in the Aube region (France): the center for short-lived low- and intermediate-level wastes, and the center for very-low-level radioactive wastes. This document is the 2010 activity report of the center for short-lived low- and intermediate-level wastes. It presents a review of the activities of the center: presentation of the installations, safety and radiation protection, events or incidents, environmental monitoring, wastes management, public information, recommendations of the Health and safety Committee (CHSCT)

  2. Autonomous System Design for Moessbauer Spectra Acquisition

    Morales, A. L.; Zuluaga, J.; Cely, A.; Tobon, J.

    2001-01-01

    An autonomous system for Moessbauer spectroscopy based in a microcontroller has been designed. A timer of the microcontroller was used to generate the control signal for the Moessbauer linear motor, and a counter for the spectra acquisition. Additionally, the system has its own memory for data storage and a serial port to transmit the data to a computer for its later processing and display

  3. An updated overview of low and intermediate level waste disposal facilities around the world

    Cuccia, Valeria; Uemura, George; Ferreira, Vinicius Verna M.; Tello, Cledola Cassia O. de; Malta, Ricardo Scott V.

    2011-01-01

    Low and intermediate level radioactive waste should be disposed off in proper disposal facilities. Some countries already have these facilities and others are planning theirs. Information about disposal facilities around the world is useful and necessary; however, data on this matter are usually scattered in official reports per country. In order to allow an easier access to this information, this paper aims to provide an overview of disposal facilities for low and intermediate level radioactive waste around the world, as updated as possible. Also, characteristics of the facilities are provided, when possible. Considering that the main source of radioactive waste are the activities of nuclear reactors in research or power generation, the paper will also provide a summarized overview of these reactors around the world, updated until April, 2011. This data collection may be an important tool for researchers, and other professionals in this field. Also, it might provide an overview about the final disposal of radioactive waste. (author)

  4. Disposal Options for Low and Intermediate-Level Radioactive Waste: Comparative Study

    Abdellatif, M.M.

    2013-01-01

    This study presents the status of current disposal options for Low and Intermediate- Level Radioactive Waste (LILRW) generated in different countries and outlines the potential for future disposal option/s of these wastes in Egypt. Since approaches used in other countries may provide useful lessons for managing Egyptian radioactive wastes. This study was based on data for19 countries repositories and we focused on 6 countries, which considered as leaders in the field of disposal of rad waste. Several countries have plans for repositories which are sufficiently advanced that it was based on their own of their extensive experience with nuclear power generation and with constructing and operating LLRW disposal facilities. On the other hand, our programme for site selection and host rock characterization for low and intermediate level radioactive waste disposal is under study. We are preparing our criteria for selecting a national repository for LIL rad waste.

  5. International co-ordinated research project on low and intermediate level waste package performance

    Dayal, R.

    2001-01-01

    As part of IAEA's mandate to facilitate the transfer and exchange of information amongst Member States, the Agency is currently coordinating an international R and D project, involving 12 developed and developing countries, on Performance of Low and Intermediate Level Waste Packages under Disposal Conditions. This paper will review the current status of the Coordinated Research Project (CRP) and summarize the key findings of the work completed to date within the context of the CRP in the participating Member States. (author)

  6. Types of organic materials present in BNFL intermediate level waste streams

    Barlow, P.

    1988-01-01

    This presentation lists the constituents present in BNFL intermediate-level radioactive wastes. The inorganic and organic components are listed and there is a detailed analysis of the plutonium contaminated materials in terms of proportion of combustible and non-combustible content, up to the year 2000. A description of the Waste Treatment Complex at Sellafield is presented. The research programme for leach testing, sorption and solubility testing and decomposition of organic matter was outlined. (U.K.)

  7. Characterisation of long-lived low and intermediate-level radioactive wastes in the Nordic Countries

    Broden, K.; Carugati, S.; Brodersen, K.; Carlsson, T.; Viitanen, P.; Walderhaug, T.; Sneve, M.; Hornkjoel, S.; Backe, S.

    1997-11-01

    The present report is final report from a study on characterisation of radioactive waters in the Nordic countries. The study has mainly been focused on long-lived low and intermediate level radioactive waste. Methods to measure or estimate the activity content and the general composition are discussed. Recommendations are given regarding characterisation of waste under treatment and characterisation of already produced waste packages. (au)

  8. Characterisation of long-lived low and intermediate-level radioactive wastes in the Nordic Countries

    Broden, K. [Studsvik RadWaste AB, (El Salvador); Carugati, S.; Brodersen, K. [Forskningscenter Risoe, (Denmark); Carlsson, T.; Viitanen, P. [VVT, (Finland); Walderhaug, T. [Icelandic Radiation Protection Institute (Iceland); Sneve, M.; Hornkjoel, S. [Norwegian Radiation Protection Authority (Norway); Backe, S. [Institute for Energy Technology (Norway)

    1997-11-01

    The present report is final report from a study on characterisation of radioactive waters in the Nordic countries. The study has mainly been focused on long-lived low and intermediate level radioactive waste. Methods to measure or estimate the activity content and the general composition are discussed. Recommendations are given regarding characterisation of waste under treatment and characterisation of already produced waste packages. (au).

  9. Disposal approach for long-lived low and intermediate-level radioactive waste

    Park, Jin Beak; Park, Joo Wan; Kim, Chang Lak

    2005-01-01

    There certainly exists the radioactive inventory that exceeds the waste acceptance criteria for final disposal of the low and intermediate-level radioactive waste. In this paper, current disposal status of the long-lived radioactive waste in several nations are summarized and the basic procedures for disposal approach are suggested. With this suggestion, intensive discussion and research activities can hopefully be launched to set down the possible resolutions to dispose of the long-lived radioactive waste

  10. The duration of the institutional controls on the low and intermediate level waste repositories

    Yang Jie; Li Yang; Liu Yafang; Lian Bing; Zhao Yangjun; Chen Hailong; Gu Zhijie

    2014-01-01

    Appropriate institutional controls are put in place prior to repository closure. Such controls can guarantee the long term safety of the repository. Today there is no clear standard on how to determine the institutional control period. This paper tries to give possible factors and activities of the institutional controls on the low and intermediate level waste repositories, and makes some suggestions on the institutional controls in our country. (authors)

  11. Removal of radioruthenium from alkaline intermediate level radioactive waste solution : a laboratory investigation

    Samanta, S.K.; Theyyunni, T.K.

    1994-01-01

    Various methods were investigated in the laboratory for the removal of radioruthenium from alkaline intermediate level radioactive waste solutions of reprocessing plant origin. The methods included batch equilibration with different ion exchangers and sorbents, column testing and chemical precipitation. A column method using zinc-activated carbon mixture and a chemical precipitation method using ferrous salt along with sodium sulphite were found to be promising for plant scale application. (author). 10 refs., 3 figs., 7 tabs

  12. Estimation of the conditioning and storage costs of low- and intermediate-level solid radioactive wastes

    Lo Moro, A.; Panciatici, G.

    1977-01-01

    The conditioning and storage costs of low- and intermediate-level solid radioactive wastes are analyzed. The cost of direct labour is assumed as the reference cost for their computation and the storage cost is considered as resulting from the contract cost ''una tantum'' and from the leasing cost. As an example, the cost trends are reported, relevant to the solution adopted at CAMEN (conditioning in concrete containers and storage on concrete open-air bed)

  13. Cement-based processes for the immobilization of intermediate level radioactive waste

    Brown, D.J.; Lee, D.J.; Price, M.S.T.; Smith, D.L.G.

    1985-01-01

    Increasing attention is being paid to the use of cement-based materials for the immobilisation of intermediate level wastes. Various cementitious materials are surveyed and the use of blast furnace slag is shown to be advantageous. The properties of cemented wastes are surveyed both during processing and as solid products. The application of Winfrith Cementation Laboratory technology to plant and flowsheet development for Winfrith Reactor sludge immobilisation is described. (author)

  14. Engineering design study for storage and disposal of intermediate level waste

    Griffin, J R; Hackney, S; Richardson, J A; Heafield, W

    1982-11-01

    A conceptual design study is presented which covers both the storage and disposal of intermediate level waste; repositories in several rock formations are considered at a 300m depth. A total system is proposed including an engineered trench for ..beta gamma.. waste, emplacement systems and off site transportation. Safety during the emplacement phase and the radiological effects of human intrusion and geological catastrophies are considered.

  15. Transport, handling, and interim storage of intermediate-level transuranic waste at the INEL

    Metzger, J.C.; Snyder, A.M.

    1977-09-01

    The Idaho National Engineering Laboratory stores transuranic (TRU)-contaminated waste emitting significant amounts of beta-gamma radiation. This material is referred to as intermediate-level TRU waste. The Energy Research and Development Administration requires that this waste be stored retrievably during the interim before a Federal repository becomes operational. Waste form and packaging criteria for the eventual storage of this waste at a Federal repository, i.e., the Waste Isolation Pilot Plant (WIPP), have been tentatively established. The packaging and storage techniques now in use at the Idaho National Engineering Laboratory are compatible with these criteria and also meet the requirement that the waste containers remain in a readily-retrievable, contamination-free condition during the interim storage period. The Intermediate Level Transuranic Storage Facility (ILTSF) provides below-grade storage in steel pipe vaults for intermediate-level TRU waste prior to shipment to the WIPP. Designated waste generating facilities, operated for the Energy Research and Development Administration, use a variety of packaging and transportation methods to deliver this waste to the ILTSF. Transfer of the waste containers to the ILTSF storage vaults is accomplished using handling methods compatible with these waste packaging and transport methods

  16. Conceptual designs for waste quality checking facilities for low level and intermediate level radioactive wastes and hazardous waste

    Driver, S.; Griffiths, M.; Leonard, C.D.; Smith, D.L.G.

    1992-01-01

    This report summarises work carried out on the design of facilities for the quality checking of Intermediate and Low Level Radioactive Waste and Hazardous Waste. The procedures used for the quality checking of these categories of waste are summarised. Three building options are considered: a separate LLW facility, a combined facility for LLW and HW and a Waste Quality Checking Facility for the three categories of waste. Budget Cost Estimates for the three facilities are given based on 1991 prices. (author)

  17. Impact of low-level BK polyomavirus viremia on intermediate-term renal allograft function.

    Korth, Johannes; Widera, Marek; Dolff, Sebastian; Guberina, Hana; Bienholz, Anja; Brinkhoff, Alexandra; Anastasiou, Olympia Evdoxia; Kribben, Andreas; Dittmer, Ulf; Verheyen, Jens; Wilde, Benjamin; Witzke, Oliver

    2018-02-01

    BK polyomavirus (BKPyV)-associated nephropathy (PyVAN) is a significant cause of premature renal transplant failure. High-level BKPyV viremia is predictive for PyVAN; however, low-level BKPyV viremia does not necessarily exclude the presence of PyVAN. As data are limited regarding whether or not low-level BKPyV viremia has an effect on intermediate-term graft outcome, this study analyzes the impact of low-level BKPyV viremia on intermediate-term graft function and outcome compared with high-level viremia and non-viremic patients. All renal transplant patients received follow-up examinations at the Department of Nephrology, University Hospital Essen. Patients were screened for BKPyV viremia and stratified into three groups according to their maximum BKPyV load in serum (low-level viremia, high-level viremia, and no viremia). In 142 of 213 (67%) patients, BKPyV was never detected in serum; 42 of 213 (20%) patients were found positive for low-level viremia (≤10 4 copies/mL); and 29 of 213 (13%) patients showed high-level viremia (>10 4 copies/mL). No significant differences regarding transplant function and graft failure were observed between patients without BKPyV viremia (delta estimated glomerular filtration rate [eGFR] +0.1 mL/min [month 1 vs last visit at month 44]) and patients with low-level BKPyV viremia (delta eGFR -1.7 mL/min). In patients with high-level viremia, transplant function was significantly restricted (delta eGFR -6.5 mL/min) compared with low-level viremia until the last visit at 44 ± 9.7 months after transplantation. Although the graft function and graft loss were worse in the high-level viremia group compared with no viremia (eGFR 37 vs 45 mL/min), the difference was not significant. High-level viremia was associated with impaired graft function. In contrast, low-level BKPyV viremia had no significant impact on intermediate-term graft function. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Region based route planning - Multi-abstraction route planning based on intermediate level vision processing

    Doshi, Rajkumar S.; Lam, Raymond; White, James E.

    1989-01-01

    Intermediate and high level processing operations are performed on vision data for the organization of images into more meaningful, higher-level topological representations by means of a region-based route planner (RBRP). The RBRP operates in terrain scenarios where some or most of the terrain is occluded, proceeding without a priori maps on the basis of two-dimensional representations and gradient-and-roughness information. Route planning is accomplished by three successive abstractions and yields a detailed point-by-point path by searching only within the boundaries of relatively small regions.

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

    2002-12-01

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

  20. Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

    Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B.

    2017-01-01

    The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, 3 H, 14 C, 55 Fe, 59 Ni, 63 Ni, 90 Sr, 93 Zr, 94 Nb, 99 Tc, 129 I, 235 U, 238 U, 238 Pu, 239 + 240 Pu, 241 Pu, 242 Pu, 241 Am, 242 Cm e 243 + 244 Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

  1. Moessbauer lineshape analysis by the DISPA method

    Miglierini, M.; Sitek, J.

    1986-01-01

    To evaluate the Moessbauer spectral parameters and hence, the structural and magnetic properties the lineshape should be known. A plot of dispersion versus absorption (DISPA plot) for a pure Lorentzian gives a perfect circle. Directions and magnitudes of DISPA distortions from this reference circle point out the kind of line-broadening mechanism observed. A possibility of the application of the DISPA technique in the Moessbauer lineshape analysis is dealt with in this paper. The method is verified on Moessbauer spectra of sodium nitroprusside, natural iron, and stainless steel. The lineshape of an amorphous metallic alloy Fe 40 Ni 40 B 20 is studied by means of the DISPA plots. (author)

  2. Various applications of the Moessbauer effect

    Legrand, Janine

    1961-06-01

    After having briefly recalled the experiments of resonant absorption of γ photons performed by Moessbauer in 1958 and the interpretation of the results, the author briefly recalls some generalities about the Moessbauer Effect: recoil and thermal agitation, possibility of recoil-free emission, example on tin. The second part addresses the phenomenon of resonant scattering: definition and calculation of atomic scattering, definition of resonant scattering, and experimental measurement of the proportion of Moessbauer photons. The last part reports the study of various bronze samples (the interest of these materials is outlined) [fr

  3. Moessbauer spectroscopy in neptunium compounds

    Nakamoto, Tadahiro; Nakada, Masami; Masaki, Nobuyuki; Saeki, Masakatsu [Japan Atomic Energy Research Inst., Tokyo (Japan)

    1997-03-01

    Moessbauer effects are observable in seven elements of actinides from {sup 232}Th to {sup 247}Cm and Moesbauer spectra have been investigated mainly with {sup 237}Np and {sup 238}U for the reasons of availability and cost of materials. This report describes the fundamental characteristics of Moessbauer spectra of {sup 237}Np and the correlation between the isomer shift and the coordination number of Np(V) compounds. The isomer shifts of Np(V) compounds had a tendency to increase as an increase of coordination number and the isomer shifts of Np(V) compounds showed broad distribution as well as those of Np(VI) but {delta} values of the compounds with the same coordination number were distributed in a narrow range. The {delta} values of Np(VI) complexes with O{sub x} donor set suggest that the Np atom in its hydroxide (NpO{sub 2}(OH){center_dot}4H{sub 2}O)might have pentagonal bipyramidal structure and at least, pentagonal and hexagonal bipyramidal structures might coexist in its acetate and benzoate. Really, such coexistence has been demonstrated in its nitrate, (NpO{sub 2}){sub 2}(NO{sub 3}){sub 2}{center_dot}5H{sub 2}O. (M.N.)

  4. Moessbauer study of Slovak meteorites

    Lipka, J.; Sitek, J.; Dekan, J., E-mail: julius.dekan@stuba.sk; Degmova, J. [Slovak University of Technology, Institute of Nuclear and Physical Engineering, Faculty of Electrical Engineering and Information Technology (Slovakia); Porubcan, V. [Comenius University, Faculty of Mathematics and Physics (Slovakia)

    2013-04-15

    {sup 57}Fe Moessbauer spectroscopy was used as an analytical tool in the investigation of iron containing compounds of two meteorites (Rumanova and Kosice) out of total of six which had fallen on Slovak territory. In the magnetic fraction of the iron bearing compounds in the Rumanova meteorite, maghemite, troilite and Fe-Ni alloy were identified. In the non-magnetic fraction silicate phases were found, such as olivine and pyroxene. The paramagnetic component containing Fe{sup 3 + } ions corresponds probably to small superparamagnetic particles. The Kosice meteorite was found near the town of Kosice in February 2010. Its magnetic fraction consists of a Fe-Ni alloy with the Moessbauer parameters of the magnetic field corresponding to kamacite {alpha}-Fe(Ni, Co) and troilite. The non-magnetic part consists of Fe{sup 2 + } phases such as olivine and pyroxene and traces of a Fe{sup 3 + } phase. The main difference between these meteorites is their iron oxide content. These kinds of analyses can bring important knowledge about phases and compounds formed in extraterrestrial conditions, which have other features than their terrestrial analogues.

  5. Generation, transport and conduct of radioactive wastes of low and intermediate level

    Lizcano, D.; Jimenez, J.

    2005-01-01

    The technological development of the last decades produced an increment in the application of the radiations in different human activities. The effect of it has been it the production of radioactive wastes of all the levels. In Mexico, some of the stages of the administration of the waste of low and intermediate level have not been completely resolved, as the case of the treatment and the final storage. In this work aspects of the generation, the transport and the administration of radioactive waste of low and intermediate level produced in the non energy applications from the radioactive materials to national level, indicating the generated average quantities, transported and tried annually by the National Institute of Nuclear Research (ININ). The main generators of wastes in Mexico, classified according to the activity in which the radioactive materials are used its are listed. Some of the main processes of treatment of radioactive wastes broadly applied in the world and those that are used at the moment in our country are also presented. (Author)

  6. Project Guarantee 1985. Repository for low- and intermediate-level radioactive waste: construction and operation

    Anon.

    1985-01-01

    A constructional engineering project study aimed at clarification of the feasibility of a repository for low- and intermediate-level radioactive waste (type B repository) has been carried out; the study is based on a model data-set derived from the geological, rock mechanical and topographical characterictics of one of Nagra's planned exploration areas. Final storage is effected in subterranean rock caverns accessed by horizontal tunnel. The reception area also is sited below the surface. Storage is conceived in such a way that, after closure of the repository, maintenance and supervision can be dispensed with and a guarantee of high long-term safety can nevertheless be provided. The envisaged repository consists of an entry tunnel for road vehicles and a reception area with a series of caverns for receiving waste, for additional technical facilities and for the production of the concrete back-fill material. The connecting tunnel is serviced by a tunnel railway and the actual repository area consists of several storage caverns. The repository is intended to accomodate a total of 200'000 m3 of solidified low- and intermediate-level waste. Valanginian marl is assumed as the host rock, although it would also be basically possible to house the proposed installations in other host rocks. The excavated material will total around 1'000'000 m3. The construction time for the whole installation is estimated as about 7 years and a working team of around 30 people will be required for the estimated 60-year operational duration. The project described in the present report justifies the conclusion that construction of a repository for low-and intermediate-level radioactive waste is feasible with present-day technology. This conclusion takes into consideration quantitative and operational constraints as well as geological and hydrogeological data relevant to constructional engineering. The latter are derived from a model data-set based on a specific locality

  7. Neuroscience Intermediate-Level Care Units Staffed by Intensivists: Clinical Outcomes and Cost Analysis.

    Kyeremanteng, Kwadwo; Hendin, Ariel; Bhardwaj, Kalpana; Thavorn, Kednapa; Neilipovitz, Dave; Kubelik, Dalibour; D'Egidio, Gianni; Stotts, Grant; Rosenberg, Erin

    2017-01-01

    With an aging population and increasing numbers of intensive care unit admissions, novel ways of providing quality care at reduced cost are required. Closed neurointensive care units improve outcomes for patients with critical neurological conditions, including decreased mortality and length of stay (LOS). Small studies have demonstrated the safety of intermediate-level units for selected patient populations. However, few studies analyze both cost and safety outcomes of these units. This retrospective study assessed clinical and cost-related outcomes in an intermediate-level neurosciences acute care unit (NACU) before and after the addition of an intensivist to the unit's care team. Starting in October 2011, an intensivist-led model was adopted in a 16-bed NACU unit, including daytime coverage by a dedicated intensivist. Data were obtained from all patients admitted 1 year prior to and 2 years after this intervention. Primary outcomes were LOS and hospital costs. Safety outcomes included mortality and readmissions. Descriptive and analytic statistics were calculated. Individual and total patient costs were calculated based on per-day NACU and ward cost estimates and significance measured using bootstrapping. A total of 2931 patients were included over the study period. Patients were on average 59.5 years and 53% male. The most common reasons for admission were central nervous system (CNS) tumor (27.6%), ischemic stroke (27%), and subarachnoid hemorrhage (11%). Following the introduction of an intensivist, there was a significant reduction in NACU and hospital LOS, by 1 day and 3 days, respectively. There were no differences in readmissions or mortality. Adding an intensivist produced an individual cost savings of US$963 in NACU and US$2687 per patient total hospital stay. An intensivist-led model of intermediate-level neurointensive care staffed by intensivists is safe, decreases LOS, and produces cost savings in a system increasingly strained to provide quality

  8. Modeling and Analysis on Radiological Safety Assessment of Low- and Intermediate Level Radioactive Waste Repository

    Lee, Youn Myoung; Jung, Jong Tae; Kang, Chul Hyung (and others)

    2008-04-15

    Modeling study and analysis for technical support for the safety and performance assessment of the low- and intermediate level (LILW) repository partially needed for radiological environmental impact reporting which is essential for the licenses for construction and operation of LILW has been fulfilled. Throughout this study such essential area for technical support for safety and performance assessment of the LILW repository and its licensing as gas generation and migration in and around the repository, risk analysis and environmental impact during transportation of LILW, biosphere modeling and assessment for the flux-to-dose conversion factors for human exposure as well as regional and global groundwater modeling and analysis has been carried out.

  9. Environmental effects of disposal of intermediate-level wastes by shale fracturing

    Weeren, H.O.

    1978-01-01

    Shale fracturing is a process currently being used at the Oak Ridge National Laboratory for the permanent disposal of locally generated, intermediate-level waste solutions. In this process, the waste is mixed with a solids blend of cement and other additives; the resulting grout is then injected into an impermeable shale formation at a depth of 700 to 1000 ft. A few hours after completion of the injection, the grout sets and the radioactive waste are fixed in the shale formation. An analysis of environmental effects of normal operation and possible accident situations is discussed

  10. Modeling and Analysis on Radiological Safety Assessment of Low- and Intermediate Level Radioactive Waste Repository

    Lee, Youn Myoung; Jung, Jong Tae; Kang, Chul Hyung

    2008-04-01

    Modeling study and analysis for technical support for the safety and performance assessment of the low- and intermediate level (LILW) repository partially needed for radiological environmental impact reporting which is essential for the licenses for construction and operation of LILW has been fulfilled. Throughout this study such essential area for technical support for safety and performance assessment of the LILW repository and its licensing as gas generation and migration in and around the repository, risk analysis and environmental impact during transportation of LILW, biosphere modeling and assessment for the flux-to-dose conversion factors for human exposure as well as regional and global groundwater modeling and analysis has been carried out

  11. Study of Radiation Shielding Analysis for Low-Intermediate Level Waste Transport Ship

    Kim, Dohyung; Lee, Unjang; Song, Yangsoo; Kim, Sukhoon; Ko, Jaehoon [Korea Nuclear Engineering and Service Corporation, Seoul (Korea, Republic of)

    2007-07-01

    In Korea, it is planed to transport Low-Intermediate Level Radioactive Waste (LILW) from each nuclear power plant site to Kyongju LILW repository after 2009. Transport through the sea using ship is one of the most prospective ways of LILW transport for current situation in Korea. There are domestic and international regulations for radiation dose limit for radioactive material transport. In this article, radiation shielding analysis for LILW transport ship is performed using 3-D computer simulation code, MCNP. As a result, the thickness and materials for radiation shielding walls next to cargo in the LILW transport ship are determined.

  12. International co-ordinated research project on low and intermediate level waste package performance

    Dayal, R. [International Atomic Energy Agency IAEA, Vienna (Austria)

    2001-07-01

    As part of IAEA's mandate to facilitate the transfer and exchange of information amongst Member States, the Agency is currently coordinating an international R and D project, involving 12 developed and developing countries, on Performance of Low and Intermediate Level Waste Packages under Disposal Conditions. This paper will review the current status of the Coordinated Research Project (CRP) and summarize the key findings of the work completed to date within the context of the CRP in the participating Member States. (author)

  13. Good Old-Fashioned Artificial Consciousness and the Intermediate Level Fallacy

    Riccardo Manzotti

    2018-04-01

    Full Text Available Recently, there has been considerable interest and effort to the possibility to design and implement conscious robots, i.e., the chance that robots may have subjective experiences. Typical approaches as the global workspace, information integration, enaction, cognitive mechanisms, embodiment, i.e., the Good Old-Fashioned Artificial Consciousness, henceforth, GOFAC, share the same conceptual framework. In this paper, we discuss GOFAC's basic tenets and their implication for AI and Robotics. In particular, we point out the intermediate level fallacy as the central issue affecting GOFAC. Finally, we outline a possible alternative conceptual framework toward robot consciousness.

  14. Investigations on cement/polymer Waste packages containing intermediate level waste and organic exchange resins

    ELsourougy, M R; Zaki, A A; Aly, H F [Atomic energy authority, hot laboratory center, Cairo, (Egypt); Khalil, M Y [Nuclear engineering department, Alexandria university. Alexandria, (Egypt)

    1995-10-01

    Polymers can be added to cements to improve its nuclear waste immobilization properties. This trend in cementation processes is attracting attention and requiring through investigations. In this work, polymers of different kinds were added to ordinary portland cement for the purpose of solidifying intermediate level liquid wastes and organic ion exchange resins. Epoxy polymer such as Kemapoxy-150 reduced the leaching rate of cesium compared to cement alone. Latex to cement ratio less than 4% caused an increase in leaching rate of cesium. When cesium was absorbed to an organic resin its leachability was improved. 5 figs., 4 tabs.

  15. Influence of time dependent effects on the disposal environments of low and intermediate level radioactive wastes

    1984-12-01

    Reviews are presented firstly of potential events and processes which may affect the evolution of the disposal environments of low and intermediate level radioactive wastes in Britain and secondly of previous studies carried out worldwide in the field of time dependent effects. From the latter review available methodologies for incorporating time dependence into radiological assessments are identified. Finally, proposals are presented for the design and development of a time dependent effects model, based on the existing far field state model (FFSM) developed for ONWI in USA. (author)

  16. Comparison of bitumen and cement immobilization of intermediate- and low-level radioactive waste

    Voss, J.W.

    1979-01-01

    This paper discusses a systems comparison of two available immobilization processes for intermediate- and low-level radioactive wastes -- bitumen and cement. This study examines a conceptual coprocessed UO 2 - PuO 2 fuel cycle. Radioactive wastes are generated at each stage of this fuel cycle. This study focuses on these transuranic (TRU) wastes generated at a conceptual Fuel Coprocessing Facility. In this report, these wastes are quantified, the immobilization systems conceptualized to process these wastes are presented, and a comparison of the systems is made

  17. Investigations on cement/polymer Waste packages containing intermediate level waste and organic exchange resins

    ELsourougy, M.R.; Zaki, A.A.; Aly, H.F.; Khalil, M.Y.

    1995-01-01

    Polymers can be added to cements to improve its nuclear waste immobilization properties. This trend in cementation processes is attracting attention and requiring through investigations. In this work, polymers of different kinds were added to ordinary portland cement for the purpose of solidifying intermediate level liquid wastes and organic ion exchange resins. Epoxy polymer such as Kemapoxy-150 reduced the leaching rate of cesium compared to cement alone. Latex to cement ratio less than 4% caused an increase in leaching rate of cesium. When cesium was absorbed to an organic resin its leachability was improved. 5 figs., 4 tabs

  18. Digital low level rf control system with four different intermediate frequencies for the International Linear Collider

    Wibowo, Sigit Basuki; Matsumoto, Toshihiro; Michizono, Shinichiro; Miura, Takako; Qiu, Feng; Liu, Na

    2017-09-01

    A field programmable gate array-based digital low level rf (LLRF) control system will be used in the International Linear Collider (ILC) in order to satisfy the rf stability requirements. The digital LLRF control system with four different intermediate frequencies has been developed to decrease the required number of analog-to-digital converters in this system. The proof of concept of this technique was demonstrated at the Superconducting RF Test Facility in the High Energy Accelerator Research Organization, Japan. The amplitude and phase stability has fulfilled the ILC requirements.

  19. The principles of design of a shallow disposal site for low and intermediate level radioactive wastes

    Holmes, R.E.

    1985-01-01

    This paper addresses the principles of design of a shallow disposal site for low and intermediate level radioactive wastes. The objective of the author is to review the need for shallow land disposal facilities in the UK and to propose design principles which will protect the public and operatives from excessive risk. It is not the intent of the author to present a detailed design of facility which will meet the design standards proposed although such a design is feasible and within the scope of currently available technology. The principles and standards proposed in this paper are not necessarily those of PPC Consultant Services Ltd. or NEI Waste Technologies Ltd. (author)

  20. Technical factors in the site selection for a radioactive wastes storage of low and intermediate level

    Badillo A, V. E.; Ramirez S, J. R.; Palacios H, J. C.

    2009-10-01

    The storage on surface or near surface it is viable for wastes of low and intermediate level which contain radio nuclides of short half life that would decay at insignificant levels of radioactivity in some decades and also radio nuclides of long half life but in very low concentrations. The sites selection, for the construction of radioactive waste storages, that present an appropriate stability at long term, a foreseeable behavior to future and a capacity to fulfill other operational requirements, is one of the great tasks that confront the waste disposal agencies. In the selection of potential sites for the construction of a radioactive wastes storage of low and intermediate level, several basic judgments should be satisfied that concern to physiography, climatology, geologic, geo-hydrology, tectonic and seismic aspects; as well as factors like the population density, socioeconomic develops and existent infrastructure. the necessary technician-scientific investigations for the selection of a site for the construction of radioactive waste storages are presented in this work and they are compared with the pre-selection factors realized in specify areas in previous studies in different regions of the Mexican Republic. (Author)

  1. The packaging and transport of low and intermediate level radioactive wastes

    Grover, J.R.; Price, M.S.T.

    1985-01-01

    Up to the present time, the majority of the radioactive waste which has been transported in the United Kingdom has been low level waste for disposal in the trenches of the shallow burial site operated by British Nuclear Fuels plc at Drigg and also the packaged waste destined for sea disposal in the annual operation. However, the main bulk of the low and intermediate level wastes which have been generated over the last quarter century remain in store at the various nuclear sites where it originated. Before significant packaging and transport of intermediate level wastes takes place it is desirable to examine the sources and types of wastes, the immobilisation and packaging processes and plants, the transport, and the problems of handling of packages at future land repositories. Optimisation of the packaging and transport must take account of both the upstream and downstream con=straints as well as the implications of complying with both the IAEA Transport Regulations and radiological protection guidelines. Packages for sea disposal must in addition comply with the requirements of the London Dumping Convention and the NEA guidelines. (author)

  2. Immobilization of low and intermediate level radioactive liquid wastes using some industrial by-product materials

    Sami, N.M.; EI-Dessouky, M.I.; Abou EI-Nour, F.H.; Abdel-Khalik, M.

    2006-01-01

    Immobilization of low and intermediate level.radioactive liquid wastes in different matrices: ordinary Portland cement and cement mixed with some industrial byproduct: by-pass kiln cement dust, blast furnace slag and ceramic sludge was studied. The effect of these industrial by-product materials on the compressive strength, water immersion, radiation effect and teachability were investigated. The obtained results showed that, these industrial by-product improve the cement pastes where they increase the compressive strength, decrease the leaching rate for radioactive cesium-137 and cobalt-60 ions through the solidified waste forms and increase resistance for y-radiation. It is found that, solidified waste forms of intermediate level liquid waste (ILLW) had high compressive strength values more than those obtained from low level liquid waste (LLLW). The compressive strength increased after immersion in different leachant for one and three months for samples with LLLW higher than those obtained for ILLW. The cumulative fractions released of cesium-137 and cobalt-60 of solidified waste forms of LLLW was lower than those obtained for ILLW

  3. Moessbauer Spectroscopy study of Quimsachata Volcano materials

    Dominguez, A.G.B.

    1988-01-01

    It has been studied volcanic lava from Quimsachata Volcano in Pem. Moessbauer Spectroscopy, X-ray diffraction, electronic and optical microscopy allowed the identification of different mineralogical phases. (A.C.AS.) [pt

  4. Surface-type repository for low and intermediate level radioactive waste in the Republic of Croatia

    Kucar-Dragicevic, S.; Zarkovic, V.; Subasic, D.

    1995-01-01

    The low-level intermediate-level (LL/IL) radioactive waste repository siting and construction project is one of the activities related to establishing the rad waste management system in the Republic of Croatia. The repository project design is one in an array of project activities which also include the site selection procedure and public attitude issues. The prepared design documentation gives technical, safety and financial background relevant for making a final decision on the waste disposal type, and it includes the technological, mechanical, civil and financial documentation on the preliminary/basic design level. During the last few years, the preliminary design has been prepared and safety assessment conducted for the tunnel-type LL/IL rad waste repository. As the surface-type repository is one of alternatives for final disposal the design documentation for that repository type was prepared during 1994. (author)

  5. Deconvolution of Moessbauer spectra using Voigt functions

    Flores Ll, H.J.

    1990-08-01

    The form of the resonance line in Moessbauer spectroscopy is a form of Lorentzian line, but this form of line it enlarges due to several effects: finite thickness of the absorber, instrumental instability, diffusion of Co 57 in crystals and fluctuations in the environment of the emitting nucleus. To take into account this effects it has been used as form of line in Moessbauer spectroscopy the Voigt function that is the convolution of a Lorentzian and a Gaussian. (Author)

  6. A Moessbauer study of deep sea sediments

    Minai, Y.; Tominaga, T.; Furuta, T.; Kobayashi, K.

    1981-01-01

    In order to determine the chemical states of iron in deep sea sediments, Moessbauer spectra of the sediments collected from various areas of the Pacific have been measured. The Moessbauer spectra were composed of paramagnetic ferric, high-spin ferrous, and magnetic components. The correlation of their relative abundance to the sampling location and the kind of sediments may afford clues to infer the origin of each iron-bearing phase. (author)

  7. Moessbauer spectroscopy of iron in clay minerals

    Raclavsky, K.; Sitek, J.; Lipka, J.

    1975-01-01

    Selected pure clay minerals predominantly of Czechoslovak origin were studied, such as montmorillonite, nontronite, beidellite, glauconite, seladonite, illite, vermiculite, saponite, palygorskite, goethite. Moessbauer measurements were performed at room temperature with a 57 Co in Pd source. The spectra were fitted by the least square method. The parameters of the measured Moessbauer spectra are given. The values of isomer shifts, quadrupole splittings and line widths were obtained with an error of +- 0.03 mm/sec. (Z.S.)

  8. Moessbauer study of iron-sugar complexes

    Tonkovic, M.; Music, S.; Hadzija, O.; Nagy-Czako, I.; Vertes, A.

    1982-01-01

    Ferric-fructose complex has been prepared using FeCl 3 and Fe(NO 3 ) 3 solutions. Molecular weight determination and Moessbauer spectroscopic measurements proved that the ferric-fructose complex is polymeric in solid state and also in aqueous solution. The synthesis of a new iron-sorbose complex has been performed. Its Moessbauer spectra indicate a structure similar to that of the iron-fructose complex. (author)

  9. 57Fe Moessbauer studies on natural chromites

    Das, D.; Sudarshan, M.; Chintalapudi, S.N.; Chakravorty, K.L.

    1996-01-01

    Five chromite samples procured from two different belts of India have been studied by 57 Fe Moessbauer spectroscopy. It is shown that four symmetric doublets are sufficient to fit the chromite spectrum; the Moessbauer parameters and Fe 3+ /Fe 2+ ratio are computed. For fully oxidized chromite with only Fe 3+ , two doublets are needed and the parameters are computed. (author). 19 refs., 4 figs., 4 tabs

  10. Automation of the Analysis of Moessbauer Spectra

    Souza, Paulo A. de Jr.; Garg, R.; Garg, V. K.

    1998-01-01

    In the present report we propose the automation of least square fitting of Moessbauer spectra, the identification of the substance, its crystal structure and the access to the references with the help of a genetic algorith, Fuzzy logic, and the artificial neural network associated with a databank of Moessbauer parameters and references. This system could be useful for specialists and non-specialists, in industry as well as in research laboratories

  11. Formation of the 1:2:3 structure in Y-Ba-Cu(Fe)-O system studied by Moessbauer spectroscopy

    Valko, P.; Miglierini, M.; Sitek, J.; Hucl, M.; Gruskova, A.

    1990-01-01

    Annealing time and temperature dependence of Y, Ba, Cu, Fe nitrade mixture towards new phases creation was revealed by Moessbauer spectroscopy. The observed changes can be assigned to chemical decomposition of corresponding nitrades and creation of intermedial and final Y 1 Ba 2 (Cu 0.95 Fe 0.05 ) 3 O x phase. (orig.)

  12. Questionnaire established for the Brazilian inventory of low and intermediate level radioactive waste

    Marumo, Julio T.; Silva, Fabio; Pinto, Antonio Juscelino; Taveira, Gerson L.S.

    2015-01-01

    The Nuclear Technology Development Center (CDTN), an institute of Brazilian National Commission of Nuclear Energy (CNEN), is responsible for the technical coordination of the Brazilian Repository Project (RBMN), for Low and Intermediate Level Radioactive Wastes. To establish the inventory of the low and intermediate radioactive level waste to be disposed in the national Repository, a questionnaire was elaborated to be filled on line, via WEB, exclusively to registered users, which involved CNEN's institutes, ELETRONUCLEAR, INB and CTMSP. Based on all standardized information received from questionnaires, an easy use database to inventory the radioactive waste was created in Microsoft Access® that supported the calculation of the volume of radioactive waste treated and non-treated, stored and generated presently in Brazil. In addition, from this database it will be possible to establish some disposal procedures and the necessary area of construction. The objective of this work is to present this database and some general information about the radwastes in Brazil. (author)

  13. Questionnaire established for the Brazilian inventory of low and intermediate level radioactive waste

    Marumo, Julio T., E-mail: jtmarumo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Silva, Fabio; Pinto, Antonio Juscelino, E-mail: silvaf@cdtn.br, E-mail: ajp@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Taveira, Gerson L.S., E-mail: gersonluizst@gmail.com [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Engenharia de Producao Civil

    2015-07-01

    The Nuclear Technology Development Center (CDTN), an institute of Brazilian National Commission of Nuclear Energy (CNEN), is responsible for the technical coordination of the Brazilian Repository Project (RBMN), for Low and Intermediate Level Radioactive Wastes. To establish the inventory of the low and intermediate radioactive level waste to be disposed in the national Repository, a questionnaire was elaborated to be filled on line, via WEB, exclusively to registered users, which involved CNEN's institutes, ELETRONUCLEAR, INB and CTMSP. Based on all standardized information received from questionnaires, an easy use database to inventory the radioactive waste was created in Microsoft Access® that supported the calculation of the volume of radioactive waste treated and non-treated, stored and generated presently in Brazil. In addition, from this database it will be possible to establish some disposal procedures and the necessary area of construction. The objective of this work is to present this database and some general information about the radwastes in Brazil. (author)

  14. Licence applications for low and intermediate level waste predisposal facilities: A manual for operators

    2009-07-01

    This publication covers all predisposal waste management facilities and practices for receipt, pretreatment (sorting, segregation, characterization), treatment, conditioning, internal relocation and storage of low and intermediate level radioactive waste, including disused sealed radioactive sources. The publication contains an Annex presenting the example of a safety assessment for a small radioactive waste storage facility. Facilities dealing with both short lived and long lived low and intermediate level waste generated from nuclear applications and from operation of small nuclear research reactors are included in the scope. Processing and storage facilities for high activity disused sealed sources and sealed sources containing long lived radionuclides are also covered. The publication does not cover facilities processing or storing radioactive waste from nuclear power plants or any other industrial scale nuclear fuel cycle facilities. Disposal facilities are excluded from the scope of this publication. Authorization process can be implemented in several stages, which may start at the site planning and the feasibility study stage and will continue through preliminary design, final design, commissioning, operation and decommissioning stages. This publication covers primarily the authorization needed to take the facility into operation

  15. Corrosion of steel drums containing simulated radioactive waste of low and intermediate level

    Farina, S.B.; Schulz Rodríguez, F.; Duffó, G.S.

    2013-01-01

    Ion-exchange resins are frequently used during the operation of nuclear power plants and constitute radioactive waste of low and intermediate level. For the final disposal inside the repository the resins are immobilized by cementation and placed inside steel drums. The eventful contamination of the resins with aggressive species may cause corrosion problems to the drums. In order to assess the incidence of this phenomenon and to estimate the lifespan of the steel drums, in the present work, the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins contaminated with different aggressive species was studied. The aggressive species studied were chloride ions (main ionic species of concern) and sulphate ions (produced during radiolysis of the cationic exchange-resins after cementation). The corrosion rate of the steel was monitored over a time period of 900 days and a chemical and morphological analysis of the corrosion products formed on the steel in each condition was performed. When applying the results obtained in the present work to estimate the corrosion depth of the drums containing the cemented radioactive waste after a period of 300 years (foreseen durability of the Low and Intermediate Level Radioactive Waste facility in Argentina), it was found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. (author)

  16. Projection to 2035 for the radioactive wastes of low and intermediate level in Mexico

    Paredes G, L.C.; Sanchez U, S.

    2004-01-01

    It is necessary to establish in few years a definitive warehouse for the radioactive waste of low and intermediate level, generated in the country and to satisfy the necessities of their confinement in the next ones 50 to 80 years. Therefore, it is required to be considered those volumes produced annually, those stored at the present and those estimated to medium and long term. The results of the simulation of 4 cases are presented, considering the operation from the 2 nuclear power reactors to 40 and 60 years, the use of the technology of current treatment and the use of super compaction of solids, as well as the importance in the taking of decision of the methodology for the dismantlement of each reactor to the finish of their useful life. At the moment the Nuclear Power Plant of Laguna Verde, produces an average of 250 m 3 /year of radioactive waste of low and intermediate level, constituted by solid dry wastes, humid solids and liquids. In the last 3 years, the power plant has reached an effectiveness of re utilization of effluents of 95%. On the other hand, in Mexico the non energetic applications of the radioisotopes, produce annually of the order of 20 m 3 /year of solid wastes, 280 m 3 /year of liquid wastes and 300 worn out radioactive sources. (Author)

  17. Advances in technologies for the treatment of low and intermediate level radioactive liquid wastes

    1994-01-01

    In recent years the authorized maximum limits for radioactive discharges into the environment have been reduced considerably, and this, together with the requirement to minimize the volume of waste for storage or disposal and to declassify some wastes from intermediate to low level or to non-radioactive wastes, has initiated studies of ways in which improvements can be made to existing decontamination processes and also to the development of new processes. This work has led to the use of more specific precipitants and to the establishment of ion exchange treatment and evaporation techniques. Additionally, the use of combinations of some existing processes or of an existing process with a new technique such as membrane filtration is becoming current practice. New biotechnological, solvent extraction and electrochemical methods are being examined and have been proven at laboratory scale to be useful for radioactive liquid waste treatment. In this report an attempt has been made to review the current research and development of mature and advanced technologies for the treatment of low and intermediate level radioactive liquid wastes, both aqueous and non-aqueous. Non-aqueous radioactive liquid wastes or organic liquid wastes typically consist of oils, reprocessing solvents, scintillation liquids and organic cleaning products. A brief state of the art of existing processes and their application is followed by the review of advances in technologies, covering chemical, physical and biological processes. 213 refs, 33 figs, 3 tabs

  18. PIC-container for containment and disposal of low and intermediate level radioactive wastes

    Araki, Kunio; Shinji, Yoshimasa; Maki, Yasuro; Ishizaki, Kanjiro; Minegishi, Keiichi; Sudoh, Giichi.

    1981-03-01

    Steel fiber reinforced polymer-impregnated concrete (SFPIC) has been investigated for low and intermediate level radioactive waste containers. The present study has been carried out by the following stages. A) Preliminary evaluation: 60 L size container for cold and hot tests. B) Evaluation of size effect: 200 L size container for cold tests. The 60 L and 200 L containers were designed as pressure-container (without equalizer) for 500 kg/cm 2 and 700 kg/cm 2 . Polymerization of impregnated methylmethacrylate monomer for stage-A and B were performed by 60 Co-γ ray radiation and thermal catalytic polymerization, respectively. Under the loading of 500 kg/cm 2 and 700 kg/cm 2 -outside hydraulic pressure, these containers were kept in their good condition. The observed maximum strains were about 1380 x 10 -6 and 3950 x 10 -6 at the outside central position of container body for circumferential direction of the 60 L and 200 L container, respectively. An accelerated leaching test was performed by charging the concentrate of the liquid radioactive waste from JMTR in JAERI into the container. Although they were immersed in deionized water for 400 days, nuclides were not leached from the container. From results of various tests, it was evaluated that the SFPIC-container was suitable for containment and disposal of low and intermediate level radioactive wastes. There was not any great difference between the two size containers for the physical and chemical properties except in their preparation process. (author)

  19. Progress in Low and Intermediate Level Operational Waste Characterization and Preparation for Disposal at Ignalina NPP

    Poskas, P.; Adomaitis, J. E.; Ragaisis, V.

    2003-01-01

    In Lithuania about 70-80% of all electricity is generated at a single power station, Ignalina NPP, which has two RBMK-1500 type reactors. Units 1 and 2 will be closed by 2005 and 2010, respectively, taking into account the conditions of the long-term substantial financial assistance rendered by the European Union, G-7 countries and other states as well as international institutions. The Government approved the Strategy on Radioactive Waste Management. Objectives of this strategy are to develop the radioactive waste management infrastructure based on modern technologies and provide for the set of practical actions that shall bring management of radioactive waste in Lithuania in compliance with radioactive waste management principles of IAEA and with good practices in force in European Union Member States. SKB-SWECO International-Westinghouse Atom Joint Venture with participation of Lithuanian Energy Institute has prepared a reference design of a near surface repository for short-lived low and intermediate level waste. This reference design is applicable to the needs in Lithuania, considering its hydro-geological, climatic and other environmental conditions and is able to cover the expected needs in Lithuania for at least thirty years ahead. Development of waste acceptance criteria is in practice an iterative process concerning characterization of existing waste, repository development, safety and environmental impact assessment etc. This paper describes the position in Lithuania with regard to the long-term management of low and intermediate level waste in the absence of finalized waste acceptance criteria and a near surface repository

  20. Studies concerning the degradation of concrete vaults for intermediate-level radioactive waste disposal

    Duffo, Gustavo S.; Arva, Esteban A; Giordano, Celia M.; Lafont, Claudio J.

    2007-01-01

    The National Atomic Energy Commission (CNEA) is the responsible for developing a management nuclear waste disposal programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The proposed model is the near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers. Since the vault and cover are major components of the engineered barriers, the durability of this concrete structures is an important aspect for the facilities integrity. This work presents a laboratory and field investigation performed for the last 6 years on reinforced concrete specimens, in order to predict the service life of the intermediate level radioactive waste disposal vaults from data obtained from electrochemical techniques. On the other hand, the development of sensors that allow on-line measurements of rebar corrosion potential and corrosion current density; incoming oxygen flow that reaches the metal surface; concrete electrical resistivity and chloride concentration is shown. Those sensors, properly embedded in a new full scale vault (nowadays in construction), will allow the monitoring of the corrosion process of the steel rebars embedded in the structure. All the information obtained from the sensors will be used for the final design of the container in order to achieve a service life more or equal than the foreseen durability for this type of facilities. (author) [es

  1. Development of agency guidance for nuclear industry submissions for conditioning intermediate level waste

    2001-01-01

    The project was carried out by RM Consultants with the overall intention of providing the Environment Agency with a sound basis on which to develop guidance on the conditioning of intermediate level waste (ILW). Waste producers are currently in the process of retrieving and conditioning many of its ILW waste streams. This is at a time where the nature and timing of any future disposal route for these wastes is uncertain. The Agency is concerned that decisions taken on how ILW should be conditioned take into account matters of interest to the Agency, such as the future disposability of wastes, the production of secondary wastes and releases to the environment. This study provides information on the arrangements by which waste producers' proposals for the conditioning of intermediate level waste are assessed, and on the Agency's role in liaising with the Nuclear Installations Inspectorate, waste producers and Nirex. The report makes recommendations on the content and handling of waste producers' proposals in order that the Agency can satisfy itself that the environmental impact of waste conditioning and the disposability of the resultant waste packages is addressed in a timely and consistent manner

  2. Strategy for the disposal of low- and intermediate-level radwastes in Canada

    Dixon, D.F.

    The intent of the strategy described is to optimize both safety and cost of disposal by classifying waste segments according to hazardous lifetime and to match these to two or more selected disposl concepts graded according to containment and isolation capabilities. The bulk of low- and intermediate-level radwastes arising in Canada are a relatively short-lived hazard requiring isolation for no more than a few hundred years. Burial of this segment at tens-of-metres in quatenary deposits has been proposed as a concept worth evaluating. It is expected that part of the low- and intermediate-level radwastes will be potentially hazardous for geological time periods. Once methods of isolation for long-lived fuel wastes have been identified, these could be utilized for wastes requiring isolation for longer than a few hundred years. Disposal of a hard-rock vault is being evaluated as a reference concept and costs are presented. It is proposed that waste classification may consider more than two categories to further reduce costs and to better accommodate the radiological character of wastes. The overall disposal strategy should be flexible enough to account for present waste management practices and anticipated future needs

  3. Trauma surgeon becomes consultant: evaluation of a protocol for management of intermediate-level trauma patients.

    Fallon, Sara C; Delemos, David; Christopher, Daniel; Frost, Mary; Wesson, David E; Naik-Mathuria, Bindi

    2014-01-01

    At our level 1 pediatric trauma center, 9-54 intermediate-level ("level 2") trauma activations are received per month. Previously, the surgery team was required to respond to and assume responsibility for all patients who had "level 2" trauma activations. In 8/2011, we implemented a protocol where the emergency room (ER) physician primarily manages these patients with trauma consultation for surgical evaluation or admission. The purpose of this study was to prospectively evaluate the effects of the new protocol to ensure that patient safety and quality of care were maintained. We compared outcomes of patients treated PRE-implementation (10/2010-7/2011) and POST-implementation (9/2011-5/2012), including surgeon consultation rate, utilization of imaging and laboratory testing, ER length of stay, admission rate, and missed injuries or readmissions. Statistical analysis included chi-square and Student's t-test. We identified 472 patients: 179 in the PRE and 293 in the POST period. The populations had similar baseline clinical characteristics. The surgical consultation rate in the POST period was only 42%, with no missed injuries or readmissions. The ER length of stay did not change. However, in the POST period there were significant decreases in the admission rate (73% to 44%) and the mean number of CT scans (1.4 to 1), radiographs (2.4 to 1.7), and laboratory tests (5.1 to 3.3) ordered in the emergency room (all p<0.001). Intermediate-level pediatric trauma patients can be efficiently and safely managed by pediatric emergency room physicians, with surgical consultation only as needed. The protocol change improved resource utilization by decreasing testing and admissions and streamlining resident utilization in an era of reduced duty hours. © 2014.

  4. Project study for the final disposal of intermediate toxicity radioactive wastes (low- and intermediate-level radioactive wastes) in geological formations

    1980-08-01

    The present report aimed to show variations in the construction- and operation-technical feasibility of a final repository for low- and intermediate-level radioactive wastes. This report represents the summary of a project study given under contract by Nagra with a view to informing a broader public of the technical conception of a final repository. Particular stress was laid on the treatment of the individual system elements of a repository concept during the construction, operation and sealing phases. The essential basis for the project study is the origin, composition and quantity of the wastes to be disposed. The final repository described in this report is foreseen for the reception of the following low- and intermediate-level solid radioactive wastes: wastes from the nuclear power plant operation; secondary wastes from the reprocessing of nuclear fuels; wastes from the decommissioning of nuclear power plants; wastes from research, medicine and industry

  5. Moessbauer spectroscopy with synchrotron radiation

    Bergmann, U.

    1994-01-01

    The short pulse nature of synchrotron radiation makes it possible to perform Moessbauer spectroscopy in the time domain, i.e. instead of measuring the transmitted intensity time integrated as a function of source/absorber velocity, the intensity of the scattered radiation is measured time differential. The resulting time spectrum is essentially source independent and complications in the data analysis which are related to the radioactive source are completely removed. Furthermore, the large brightness and well defined polarization of the synchrotron radiation can, e.g., speed up the data collection and facilitate studies of polarization phenomena. To illustrate these new spectroscopic possibilities, measurements of the temperature dependence and polarization dependence of forward scattering from alpha - sup 5 sup 7 Fe nuclei are presented and discussed 26 refs., 5 figs. (author)

  6. Radiochemical methodologies applied to analytical characterization of low and intermediate level wastes from nuclear power plants

    Monteiro, Roberto Pellacani G.; Júnior, Aluísio Souza R.; Kastner, Geraldo F.; Temba, Eliane S.C.; Oliveira, Thiago C. de; Amaral, Ângela M.; Franco, Milton B., E-mail: rpgm@cdtn.br, E-mail: reisas@cdtn.br, E-mail: gfk@cdtn.br, E-mail: esct@cdtn.br, E-mail: tco@cdtn.br, E-mail: ama@cdtn.br, E-mail: francom@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    The aim of this work is to present radiochemical methodologies developed at CDTN/CNEN in order to answer a program for isotopic inventory of radioactive wastes from Brazilian Nuclear Power Plants. In this program some radionuclides, {sup 3}H, {sup 14}C, {sup 55}Fe, {sup 59}Ni, {sup 63}Ni, {sup 90}Sr, {sup 93}Zr, {sup 94}Nb, {sup 99}Tc, {sup 129}I, {sup 235}U, {sup 238}U, {sup 238}Pu, {sup 239}+{sup 240}Pu, {sup 241}Pu, {sup 242}Pu, {sup 241}Am, {sup 242}Cm e {sup 243}+{sup 244}Cm, were determined in Low Level Wastes (LLW) and Intermediate Level Wastes (ILW) and a protocol of analytical methodologies based on radiochemical separation steps and spectrometric and nuclear techniques was established. (author)

  7. The transport implications of regional policies for the disposal of intermediate level radioactive wastes

    James, I.A.

    1985-09-01

    This report aims to evaluate transport parameters and logistics associated with the disposal of intermediate-level radioactive wastes, as generated by CEGB, SSEB, UKAEA and BNFL. The assumed power scenario is DoE Scheme 3, which approximates to a moderate power generation scenario, with a 15 GWe PWR programme commissioned between 1991 and 2010, existing Magnox and AGR stations are assumed to have a 30 year lifespan. Three transport options are again assumed, namely; road, rail and a hybrid system, as is consistent with previous studies. These three options will be used in investigating regional policies of disposal, initially at the national level and then progressively disaggregating to a system of three regional depositories serving their respective catchment areas. (author)

  8. AERE contracts with DOE on the treatment and disposal of Intermediate Level Wastes

    Partridge, B.A.

    1985-07-01

    Individual summaries are provided for each contract report, under the titles: comparative evaluation of α and βγ irradiated medium level waste forms; modelling and characterisation of intermediate level waste forms based on polymers; optimisation of processing parameters for polymer and bitumen modified cements; α damage in non-reference matrix materials; leaching mechanisms and modelling; inorganic ion exchange treatment of medium active effluents; electrical processes for the treatment of medium active liquid waste; fast reactor fuel element cladding; dissolver residues; effects of radiation on the properties of cemented MTR waste forms; equilibrium leach testing of cemented MTR waste forms; radiolytic oxidation of radionuclides; immobilisation of liquid organic wastes; quality control, non-conformances and corrective action; application of gel processes in the treatment of actinide-containing liquid wastes; the role of colloids in the release of radionuclides from nuclear waste. (author)

  9. A methodology for assessing social considerations in transport of low and intermediate level radioactive waste

    Allsop, R.E.; Banister, D.J.; Holden, D.J.; Bird, J.; Downe, H.E.

    1986-05-01

    A methodology is proposed for taking into account non-radiological social aspects of the transport of low and intermediate level radioactive waste when considering the location of disposal facilities and the transport of waste to such facilities from the sites where it arises. As part of a data acquisition programme, an attitudinal survey of a sample of people unconnected with any suggested site or transport route is proposed in order to estimate levels of concern felt by people of different kinds about waste transport. Probabilities of accident occurrence during transport by road and rail are also discussed, and the limited extent of quantified information about consequences of accidents is reviewed. The scope for malicious interference with consignments of waste in transit is considered. (author)

  10. 49 CFR Figure 2b to Subpart B of... - Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location...

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements-§§ 238.113 and 238.114 2B Figure 2B to... Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements—§§ 238.113 and...

  11. 49 CFR Figure 2a to Subpart B of... - Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location...

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements-§§ 238.113 and 238.114 2A Figure 2A to... Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements—§§ 238.113 and...

  12. Moessbauer spectroscopy study on the hydrothermal transformation α-FeOOH → α-Fe2O3

    Barb, D.; Diamandescu, L.; Mihaila-Tarabsanu, D.; Rusi, A.; Moraria, M.

    1990-01-01

    The reaction kinetics of the hydrothermal transformation α-FeOOH→α-Fe 2 O 3 was studied by means of Moessbauer spectroscopy. From the reaction isotherms, a monomolecular, first order reaction was found to characterise the hydrothermal transformation of alpha oxihydroxide to the alpha iron oxide. The rate constant as well as the activation energy of this process were determined. No intermediate phases were identified in the hydrothermal samples. The thermodynamic properties of the hydrothermal system α-FeOOH→α-Fe 2 O 3 in correlation with Moessbauer spectroscopy data are discussed. (orig.)

  13. An assessment of filter aids and filter cloths in the dewatering of intermediate level wastes

    Knibbs, R.H.; Hudson, B.C.; Blackwell, J.C.W.

    1984-12-01

    This report considers a range of filter cloths and precoat materials intended for use in dewatering intermediate level radioactive wastes, and their interaction when used on a rotary drum vacuum filter. The report outlines the advantages and disadvantages of various grades and types of precoat and shows that grades with permeabilities in the intermediate range, 3 to 4 x 10 -12 m 2 , give satisfactory filtrate quality together with ease of operation. The work on filter cloths shows that: radiation damage is not a limiting factor as regards operational life for any of the cloths examined; polyester-based cloths are unsuitable due to their poor resistance to alkali attack; polyamide cloths are satisfactory; and stainless steel Dutch weave cloths are satisfactory and have the added advantage of high strength. The report also briefly considers the radiation resistance of two elastomeric membranes used on the 'epidermal' filter and shows that the natural latex rubber membrane is considerably more resistant to radiation than the silicone rubber membrane and has an estimated operational life of at least 1200 hours when dewatering Magnox silo sludge or α-contaminated alumino ferric flocs. (author)

  14. Investigation of students’ intermediate conceptual understanding levels: the case of direct current electricity concepts

    Aktan, D Cobanoglu

    2013-01-01

    Conceptual understanding is one of the main topics in science and physics education research. In the majority of conceptual understanding studies, students’ understanding levels were categorized dichotomously, either as alternative or scientific understanding. Although they are invaluable in many ways, namely developing new instructional materials and assessment instruments, students’ alternative understandings alone are not sufficient to describe students’ conceptual understanding in detail. This paper introduces an example of a study in which a method was developed to assess and describe students’ conceptual understanding beyond alternative and scientific understanding levels. In this study, six undergraduate students’ conceptual understanding levels of direct current electricity concepts were assessed and described in detail by using their answers to qualitative problems. In order to do this, conceptual understanding indicators are described based on science and mathematics education literature. The students’ understanding levels were analysed by assertion analysis based on the conceptual understanding indicators. The results indicated that the participants demonstrated three intermediate understanding levels in addition to alternative and scientific understanding. This paper presents the method and its application to direct current electricity concepts. (paper)

  15. Assessment of the radiological impact of disposal of low and intermediate level wastes on the seabed

    Mobbs, S.F.; Delow, C.E.; Hill, M.D.

    1984-03-01

    This report describes progress in the development of models for use in a radiological assessment of the disposal of low and intermediate level waste on the ocean floor. In particular the report describes the waste package model, the ocean dispersion model and the sedimentation model. Five types of waste package have been identified and models have been developed for them. A flow pattern for the Atlantic Ocean has been derived from the existing distribution of temperature and salinity in the Atlantic Ocean. However a number of discrepancies between the calculated and predicted pattern were found; the model has been extended to include all the world's oceans to correct this. The sedimentation model describes two types of scavenging particles in the water column, a well mixed benthic boundary layer and the top two metres of the bed sediments. Good agreement with the GESAMP ocean model results has been found. (author)

  16. Low- and Intermediate Level Radioactive Waste Disposal Environmental and Safety Assessment Activities in Slovenia

    Marc, D.; Loose, A.; Urbanc, J.

    1998-01-01

    The protection of the environment is one of the main concerns in the management of radioactive waste, especially in repository planning. In different stages of repository lifetime the environmental assessment has different functions: it can be used as a decision making process and as a planning, communication and management tool. Safety assessment as a procedure for evaluating the performance of a disposal system, and its potential radiological impact on human health and environment, is also required. Following the international recommendations and Slovene legislation, a presentation is given of the role and importance of the environmental and safety assessment activities in the early stages following concept development and site selection for a low- and intermediate level radioactive waste (LILW) repository in Slovenia. As a case study, a short overview is also given of the preliminary safety assessment that has been carried out in the analysis of possibilities for long-lived LILW disposal in Slovenia. (author)

  17. The disposal of intermediate-level radioactive liquid waste by hydraulic fracturing process

    Ruilin, Chen; Hanchen, Zhou; Yuzhu, Gao; Wen, Qiao; Wentao, Wang [Beijing Inst. of Nuclear Engineering (China)

    1994-12-31

    The hydraulic fracturing process is characterized by combination of the treatment with the disposal of ILLW (intermediate-level liquid waste). It is of cement solidification in deep geology stratum. First of all, it is necessary to select a suitable disposal site with detailed information on geology and hydrogeology. The process has such advantages as simple, low cost, large capacity of disposal, safe and reliable in technology. It is an attractive process of ILLW. Since 1980`s, the research and the concept design of the hydraulic fracturing process have been initiated for disposal of ILLW. It is demonstrated by the field tests. The authors considered that the geological structure near Sichuan Nuclear Fuel Plant fits the disposal of ILLW by the hydraulic fracturing process.

  18. Feasibility study for the disposal of low and intermediate level radioactive waste in Cuba

    Chales Suarez, G.; Peralta Vital, J.L.; Gil Castillo, R.; Franklin Saburido, R.; Rodriquez Reyes, A.; Castillo Gomez, R.

    1998-01-01

    The perspective of completing and operating the Juragua Nuclear Power Station and the development of nuclear applications justifies the need to establish an appropriate low and intermediate level radioactive waste disposal system in Cuba. The design of one option which is consonant with the characteristics of this country is presented in the form of a feasibility study. The study discusses the characteristics of the wastes, the design of the repository, the packaging of the radioactive wastes as well as the siting, conditioning and performance assessment in a preliminary stage. International practice and experience have been considered, as well as the recommendations of the International Atomic Energy Agency [1-4] in the preparation of this study. (author)

  19. The management of intermediate-level radioactive wastes arising from reprocessing operations

    Elsden, A.D.

    1984-01-01

    The reprocessing of spent nuclear fuel results in the generation of radioactive wastes in the form of liquids, gases and solids. This paper outlines the principles and major elements of the waste management systems currently in use or under development for the category of waste known as intermediate-level wastes. To enable implementation of an optimized waste management system, engineering process evaluations, development and design in the following areas are required: The definition of cost effective options taking account of constraints which may arise from other operations in the overall system, e.g. from transport requirements or from criteria derived from environmental impact assessments of alternative disposal routes; Plant and equipment development to enable acceptable system and active plant operations on an industrial scale; Safety and reliability studies to ensure adequate protection of both the general public and plant operators during all stages of the waste management system including disposal

  20. The disposal of intermediate-level radioactive liquid waste by hydraulic fracturing process

    Chen Ruilin; Zhou Hanchen; Gao Yuzhu; Qiao Wen; Wang Wentao

    1993-01-01

    The hydraulic fracturing process is characterized by combination of the treatment with the disposal of ILLW (intermediate-level liquid waste). It is of cement solidification in deep geology stratum. First of all, it is necessary to select a suitable disposal site with detailed information on geology and hydrogeology. The process has such advantages as simple, low cost, large capacity of disposal, safe and reliable in technology. It is an attractive process of ILLW. Since 1980's, the research and the concept design of the hydraulic fracturing process have been initiated for disposal of ILLW. It is demonstrated by the field tests. The authors considered that the geological structure near Sichuan Nuclear Fuel Plant fits the disposal of ILLW by the hydraulic fracturing process

  1. Mechanical properties of ductile cast iron and cast steel for intermediate level waste transport containers

    Gray, I.L.S.; Sievwright, R.W.T.; Egid, B.; Ajayi, F.; Donelan, P.

    1994-01-01

    UK Nirex Ltd is developing Type B re-usable shielded transport containers (RSTCs) in a range of shielding thicknesses to transport intermediate level radioactive waste (ILW) to a deep repository. The designs are of an essentially monolithic construction and rely principally on the plastic flow of their material to absorb the energies involved in impact events. Nirex has investigated the feasibility of manufacturing the RSTCs from ductile cast iron (DCI) or cast steel instead of from forgings, since this would bring advantages of reduced manufacturing time and costs. However, cast materials are perceived to lack toughness and ductility and it is necessary to show that sufficient fracture toughness can be obtained to preclude brittle failure modes, particularly at low temperatures. The mechanical testing carried out as part of that programme is described. It shows how the measured properties have been used to demonstrate avoidance of brittle fracture and provide input to computer modelling of the drop tests. (author)

  2. Strategic review on management and disposal of low- and intermediate-level solid radwastes

    Li Xuequn

    1993-01-01

    An overview on the actual status of solid low- and intermediate-level wastes (L/ILW) management in China is described. Some of the main problems at present are analysed. The strategies on management and disposal of the wastes are discussed in light of systematology. A large amount of solid L/ILW and distilled residual solution to be solidified have been accumulated during the past 30 years development of nuclear industry in China. These wastes, containing fission products, activated products, and uranium and transuranium elements respectively, mainly come from nuclear reactors, spent fuel reprocessing plants, and nuclear fuel fabrication plants. In the century, solid L/ILW and solidified wastes are produced mainly by nuclear industry; but in the next century, solid wastes will be steadily produced mainly from nuclear power plants

  3. OPG's deep geologic repository for low and intermediate level waste - recent progress

    King, F.K.

    2006-01-01

    This paper provides a status report on Canada's first project to build a permanent repository for the long-term management of radioactive waste. Ontario Power Generation has initiated a project to construct a deep geologic repository for low- and intermediate-level waste at the Bruce Nuclear Site, at a depth in the range of 600 to 800 m in an Ordovician-age argillaceous limestone formation. The project is currently undergoing an Environmental Assessment and consulting companies in the areas of environmental assessment, geoscientific site characterization, engineering and safety assessment have been hired and technical studies are underway. Seismic surveys and borehole drilling will be initiated in the fall of 2006. The next major milestone for the project is the submission of the Environmental Assessment report, currently scheduled for December 2008. (author)

  4. Future extension of the Swedish repository for low and intermediate level waste (SFR)

    Carlsson, Jan

    2006-01-01

    The existing Swedish repository for low and intermediate level waste (SFR) is licensed for disposal of short-lived waste originated from operation and maintenance of Swedish nuclear power plants. The repository is foreseen to be extended to accommodate short-lived waste from the future decommissioning of the Nuclear Power Plants. Long-lived waste from operation, maintenance and eventually decommissioning will be stored some years before disposal in a geological repository. This repository can be build either as a further extension of the SFR facility or as a separate repository. This paper discusses the strategy of a step-wise extended repository where the extensions are performed during operation of the existing parts of the repository. It describes the process for licensing new parts of the repository (and re-license of the existing parts). (author)

  5. Experience from developed and licensing an underground repository for low and intermediate level radioactive wastes

    Ebel, K.; Richter, D.

    1988-01-01

    In the German Democratic Republic an abandoned salt mine was selected and reconstructed to serve as a central repository for low and intermediate level wastes from nuclear power plants and radioisotope production and application from all over the country. The decision to establish such a repository was based on safety and technical-economic studies performed in the 1960s. The repository is owned by the main waste producer, the nuclear plant utility. It was designed, constructed and commissioned during 1972-1978. The licensing steps included a site licence (1972), a construction licence (1974), a comissioning licence and a continuous operation licence (1979). The paper reviews the overall choice of the disposal option, the responsibilities in radioactive waste management, the licensing and surveillance activities, the methods for transport and disposal, and the waste acceptance criteria established for the repository. (author)

  6. Performance analysis of a repository for low and intermediate level reactor waste

    Vieno, T.; Nordman, H.; Vuori, S.; Peltonen, E.

    1987-01-01

    In Finland, utilities producing nuclear energy are responsible for the management of the radioactive waste, including final disposal. As regards low and intermediate level waste, the approach has been adopted to employ the power plant sites for locations of repositories. The repositories will be excavated at the depth of about 50 to 125 m in the bedrock of the two Finnish nuclear power plant sites, Loviisa and Olkiluoto. The performance analysis presented in this paper has been carried out for the Preliminary Safety Analysis Report (PSAR) of the Olkiluoto repository. A flexible model has been developed to estimate the release of radionuclides from waste packages and their subsequent transport through the engineered barriers in the repository. Gradual degradation of the engineered barriers is accounted for by altering parameters at fixed time points. Safety margins of the disposal concept have been evaluated by including disturbed evolution scenarios in the analysis. 13 references, 10 figures, 2 tables

  7. Chemical conditions in the repository for low- and intermediate-level reactor waste

    Snellman, M.; Uotila, H.

    1984-01-01

    The chemical conditions in the proposed repositories for low- and intermediate-level reactor waste at Haestholmen (IVO) and Olkiluoto (TVO) have been discussed with respect to materials introduced into the repository, their possible long-term changes and interaction with groundwater flowing into the repository. The main possible groundwater-rock interactions have been discussed, as well as the role of micro-organisms, organic acids and colloids in the estimation of the barrier integrity. Experimental and theoretical studies have been performed on the basis of the natural groundwater compositions expected at the repository sites. Main emphasis is put on the chemical parameters which might influence the integrity of the different barriers in the repository as well as on the parameters which might effect the release and transport of radionuclides from the repository

  8. Predisposal Management of Low and Intermediate Level Radioactive Waste. Safety Guide

    2009-01-01

    The objective of this Safety Guide is to provide regulatory bodies and the operators that generate and manage radioactive waste with recommendations on how to meet the principles and requirements established for the predisposal management of low and intermediate level waste. Contents: 1. Introduction; 2. Protection of human health and the environment; 3. Roles and responsibilities; 4. General safety considerations; 5. Safety features for the predisposal management of LILW; 6. Record keeping and reporting; 7. Safety assessment; 8. Quality assurance; Annex I: Nature and sources of LILW from nuclear facilities; Annex II: Development of specifications for waste packages; Annex III: Site conditions, processes and events for consideration in a safety assessment (external natural phenomena); Annex IV: Site conditions, processes and events for consideration in a safety assessment (external human induced phenomena); Annex V: Postulated initiating events for consideration in a safety assessment (internal phenomena).

  9. Intermediate storage facility for vitrified high level waste from the reprocessing of spent nuclear fuel

    1978-04-01

    An intermediate storage facility for vitrified high level waste is described. The design was made specifically for Swedish conditions but can due to modular design be applied also for other conditions. Most of the plant is located underground with a rock cover of about 30 m in order to provide protection against external forces such as acts of war and sabotage. The storage area consists of four caverns each with 150 pits. Each pit can take 10 waste cylinders of 0.4 m diameter and 1.5 m length containing 150 liters of glass. The capacity can be increased by adding additional caverns. Cooling is obtained by forced air convection. Reception areas, auxiliary systems and operation of the plant are also described

  10. Scientific and technical basis for the near surface disposal of low and intermediate level waste

    2002-01-01

    This report presents an overview of the scientific and technical basis for the disposal of low- and intermediate-level radioactive waste in near surface repositories. The focus is on basic principles, approaches, methodologies and technical criteria that can be used to develop and assess the performance of a disposal facility, and for building confidence in repository safety. This includes consideration of the multiple barrier concept, the performance of engineered barriers, the role of natural barriers and the development of a safety case. The emphasis is on defining the conditions relevant to the containment of the radionuclides in the repository and the processes that may affect the integrity of the engineered barriers. Both generic and specific data requirements for repository development and the assurance of safety are addressed. A large number of bibliographical references are given to support the information provided in this report

  11. Cost Considerations and Financing Mechanisms for the Disposal of Low and Intermediate Level Radioactive Waste

    2007-06-01

    The overall objective of this publication is to provide Member States who are currently planning or preparing new near surface repositories for low and intermediate level radioactive waste (LILW), guidance on cost considerations and funding mechanisms for the repositories' entire life cycle. The report focuses on both technical and non-technical factors affecting repository costs. It considers the major cost elements that comprise a cost evaluation for a disposal facility for LILW and identifies those factors which may result in major uncertainties in an overall cost estimate. In particular, the report lists the basic disposal options and summarizes the legal basis and infrastructure requirements for establishing an effective financing system. It further includes the cost estimation methodology, considers the major cost categories and discusses factors to be considered when planning the financing mechanism, and describes relevant financing schemes

  12. The European Communities' research programme on management of low and intermediate level wastes

    Simon, R.; Cecille, L.

    1989-01-01

    In the European Communities' third R and D programme on Management and Disposal of Radioactive Wastes a large number of projects have been commissioned to develop treatment and conditioning processes for low and intermediate level wastes and to qualify the conditioned waste forms. The paper presents the main objectives of this research and summarizes some of the more important studies. In liquid waste treatment, the research includes processes to separate actinides by new extractive methods and application of selective inorganic ion exchangers as well as electrochemically controlled ion exchange processes and a series of purification methods involving membrane techniques. The most important issue of solid waste management in the programme is the treatment and conditioning of plutonium containing wastes, for which a strategic study had been commissioned to optimize the choice between different treatment and conditioning options. Processes being studied include two advanced decontamination techniques and a variety of conditioning methods for incinerator ash and fuel element hulls. Another task of the programme is devoted to the qualification of waste forms. This comprises the characterization of the most common low and intermediate level waste products with respect to leaching, waste form stability, radiation resistance and compatibility with the respective disposal environments. In the course of the programme, the development of methods for quality assurance and in particular quality control has become an important issue: the control of the nuclide inventory, of the chemical composition of the wastes and of the correct operation of treatment and conditioning processes is being investigated in special laboratories. (author). 21 refs, 4 tabs

  13. Divide and conquer: intermediate levels of population fragmentation maximize cultural accumulation.

    Derex, Maxime; Perreault, Charles; Boyd, Robert

    2018-04-05

    Identifying the determinants of cumulative cultural evolution is a key issue in the interdisciplinary field of cultural evolution. A widely held view is that large and well-connected social networks facilitate cumulative cultural evolution because they promote the spread of useful cultural traits and prevent the loss of cultural knowledge through factors such as drift. This view stems from models that focus on the transmission of cultural information, without considering how new cultural traits actually arise. In this paper, we review the literature from various fields that suggest that, under some circumstances, increased connectedness can decrease cultural diversity and reduce innovation rates. Incorporating this idea into an agent-based model, we explore the effect of population fragmentation on cumulative culture and show that, for a given population size, there exists an intermediate level of population fragmentation that maximizes the rate of cumulative cultural evolution. This result is explained by the fact that fully connected, non-fragmented populations are able to maintain complex cultural traits but produce insufficient variation and so lack the cultural diversity required to produce highly complex cultural traits. Conversely, highly fragmented populations produce a variety of cultural traits but cannot maintain complex ones. In populations with intermediate levels of fragmentation, cultural loss and cultural diversity are balanced in a way that maximizes cultural complexity. Our results suggest that population structure needs to be taken into account when investigating the relationship between demography and cumulative culture.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'. © 2018 The Author(s).

  14. Intermediate levels of hippocampal activity appear optimal for associative memory formation.

    Xiao Liu

    Full Text Available BACKGROUND: It is well established that hippocampal activity is positively related to effective associative memory formation. However, in biological systems often optimal levels of activity are contrasted by both sub- and supra-optimal levels. Sub-optimal levels of hippocampal activity are commonly attributed to unsuccessful memory formation, whereas the supra-optimal levels of hippocampal activity related to unsuccessful memory formation have been rarely studied. It is still unclear under what circumstances such supra-optimal levels of hippocampal activity occur. To clarify this issue, we aimed at creating a condition, in which supra-optimal hippocampal activity is associated with encoding failure. We assumed that such supra-optimal activity occurs when task-relevant information is embedded in task-irrelevant, distracting information, which can be considered as noise. METHODOLOGY/PRINCIPAL FINDINGS: In the present fMRI study, we probed neural correlates of associative memory formation in a full-factorial design with associative memory (subsequently remembered versus forgotten and noise (induced by high versus low distraction as factors. Results showed that encoding failure was associated with supra-optimal activity in the high-distraction condition and with sub-optimal activity in the low distraction condition. Thus, we revealed evidence for a bell-shape function relating hippocampal activity with associative encoding success. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that intermediate levels of hippocampal activity are optimal while both too low and too high levels appear detrimental for associative memory formation. Supra-optimal levels of hippocampal activity seem to occur when task-irrelevant information is added to task-relevant signal. If such task-irrelevant noise is reduced adequately, hippocampal activity is lower and thus optimal for associative memory formation.

  15. Transport of Spent Nuclear Fuels, High and Intermediate Level Wastes: A Continuous Challenge

    Otton, C.; Blachet, L.

    2009-01-01

    For more than 45 years TN International has been involved in the radioactive materials transportation field. Since the beginning the used nuclear fuel transportation has been its core business. During all these years TN International, now part of AREVA, has been able to anticipate and fulfil the needs for new transport or storage casks design to fit the nuclear industry evolutions. A whole fleet of casks able to transport all the materials of the nuclear fuel cycle has been developed. In this presentation we will focus on the casks for the spent fuel, high level waste and intermediate level waste transportation. Answering to the constant evolution of the nuclear industry transport needs is a challenge that TN International faces routinely. Concerning the spent nuclear fuel transportation, TN International has developed in the early 80's a fleet of TN12 type casks fitted with several types of baskets able to safely transport all the spent fuel from the nuclear power plant or the research laboratories to AREVA La Hague plant. The current challenge is the design of a new transport cask generation taking into account the needs of the industry for the next 30 years. The replacement of the TN12 cask generation is to be scheduled as the regulations have changed and the fuel characteristics have evolved. The new generation of casks will take into account all the technical evolutions made during the TN12 thirty years of use. MOX spent fuel has now its dedicated cask: the TN112 which certificate of approval has been obtained in July 2008. This cask is able to transport 12 MOX spent fuel elements with a short cooling time. The first loading of the cask has been performed in 2008 in the EDF nuclear power plant of Saint-Laurent-des-Eaux. Concerning the high level waste such as the La Hague vitrified residues a whole fleet of casks has been developed such as the TN 28 VT dedicated to transport, the TN81 and TN85 dedicated to transport and storage. These casks have permitted the

  16. A Moessbauer study of doped magnetite

    Nistor, C.I.; Boekema, C.; Woude, F. van der; Sawatzky, G.A.

    1975-01-01

    Doped magnetite was investigated by means of the Moessbauer effect to ascertain the behaviour of conduction electrons in magnetite. The Moessbauer spectrum of Fe 3 O 4 recorded at room temperature consisted of two patterns: one corresponding to the Fe 3+ (A) ions and another corresponding to the Fe(B) ions. The first A and B lines of the room temperature Moessbauer spectra of Msub(0.1)Fesub(2.9)O 4 with M = Li, Ni and Sn are presented. The B site lines of the spectra were asymmetrically broadened and showed a certain structure whereas the A site lines were narrow. In the Moessbauer spectrum of Lisub(0.2)Fesub(2.8)O 4 recorded at 407 0 C even separate lines between the A and B patterns were observed. It was found that the symmetry and line broadening were only slightly temperature dependent and were still present at higher temperatures. The application of a charge oscillation model was found to be valid only for lower impurity concentrations. The Moessbauer study of doped magnetite revealed the occurrence of spin and charge density oscillations in the B sublattice. (Z.S.)

  17. Resistance of Feather-Associated Bacteria to Intermediate Levels of Ionizing Radiation near Chernobyl.

    Ruiz-González, Mario Xavier; Czirják, Gábor Árpád; Genevaux, Pierre; Møller, Anders Pape; Mousseau, Timothy Alexander; Heeb, Philipp

    2016-03-15

    Ionizing radiation has been shown to produce negative effects on organisms, although little is known about its ecological and evolutionary effects. As a study model, we isolated bacteria associated with feathers from barn swallows Hirundo rustica from three study areas around Chernobyl differing in background ionizing radiation levels and one control study site in Denmark. Each bacterial community was exposed to four different γ radiation doses ranging from 0.46 to 3.96 kGy to test whether chronic exposure to radiation had selected for resistant bacterial strains. Experimental radiation duration had an increasingly overall negative effect on the survival of all bacterial communities. After exposure to γ radiation, bacteria isolated from the site with intermediate background radiation levels survived better and produced more colonies than the bacterial communities from other study sites with higher or lower background radiation levels. Long-term effects of radiation in natural populations might be an important selective pressure on traits of bacteria that facilitate survival in certain environments. Our findings indicate the importance of further studies to understand the proximate mechanisms acting to buffer the negative effects of ionizing radiation in natural populations.

  18. Moessbauer study of corrosion induced by acid rain

    Arshed, M.; Hussain, N.; Siddiqui, M.; Anwar-ul-Islam, M.; Rehman, S.; Butt, N.M.

    1997-01-01

    Strictly speaking acid rain refers to wet precipitation of pollutants S0/sub 2/SO/sub 3/ and NO/sub x/HNO/sub 3/ which have dissolved in cloud and rain droplets to from sulphuric and nitric acids. Acid rain has seriously damaged pine and spruce forests in Canada, USA and Europe. In these areas it has caused damage to buildings, reduced fish population due to acidification of lakes and rivers, and affected health of human beings as a result of poor water quality. The corrosion products formed in a simulated acid rain environment have been identified with transmission Moessbauer spectroscopy using a /sup 57/Co source. They were found to be gamma-FeOOH, alpha-FeOOH, gamma-Fe/sub 2/O/sub 3/ and a phase with unfamiliar parameters which seems to be amorphous in nature and can be considered as an intermediate phase. (author)

  19. An Applied Study of the Storage for Old Intermediate Level Waste at the Studsvik Site

    Sjoeblom, Rolf; Lindskog, Staffan

    2004-02-01

    The Storage for Old Intermediate Level Waste (SOILW) at Studsvik has been used for interim storage of intermediate and high level radioactive waste from various activities at the Studsvik site including post irradiation investigations. The SOILW facility was in operation during the years 1961 - 1984. The waste was stored in tube positions in concrete blocks and in concrete vaults. In some instances, radioactive debris and liquid has contaminated the storage positions as well as the underlying ventilation space. The primary purpose of the present work is to improve and extend the present knowledge basis for cost estimates for decommissioning, with the ACSF facility as an example. The main objective has been to explore the possibilities to improve the reliability and accuracy of capital budgeting for decommissioning costs at SOILW. In this study, the present international status of decommissioning, planning and cost estimation has been compiled. The various relevant guidance documents of the IAEA are also compiled, and their emphasis on the necessity of radiological and other surveying as well as technical planning and method selection is reiterated. Cost calculation schemes for new plants and for decommissioning are compiled. It is emphasized that the calculations should be carried out differently at different stages. At the early stages of decommissioning, there should be more emphasis on comparison, and at later stages the emphasis should be more oriented towards summation. The error/uncertainty in a cost calculation is strongly dependent on the selection of methodology, which, in turn, is strongly dependent on the radiological condition. The magnitude of the level of uncertainty has been illustrated by the example of concrete surface removal, and advice is provided on how to identify alternative measures that will enable more sure decisions. An example is also given on a rather similar decontamination and dismantling involving highly contaminated tubes in a

  20. Moessbauer study of hydrated iron sulfates

    Araujo, S.I.; Danon, J.; Iannarella, L.

    1991-01-01

    The hydrated iron sulfates amarantite Fe(SO sub(4))(OH).3H sub(2)O, copiapite (Mg,Al)Fe sup(3+) sub(4)(SO sub(4)) sub(6)(OH) sub(2).20H sub(2)O and ungemachite K sub(3)Na sub(9)Fe(SO sub(4)) sub(6)(OH) sub(3).9H sub(2)O were studied by Moessbauer Spectroscopy (MS) in connection with Differential Scanning Calorimetry (DSC). The effect of the dehydration on the hyperfine parameters at the Fe sites was investigated. For amarantite, the Moessbauer spectrum remained practically unchanged, while the Fe sup(3+) quadrupole splittings for copiapite and ungemachite increased. The Fe sup(2+) quadrupole splitting of ungemachite was also unchanged. We have found out the anisotropy of the recoiless absorption probability for the sup(57)Fe Moessbauer gamma ray in amarantite. The three minerals were found to be highly hygroscopic after the dehydration consequent of the DSC measurements. (author)

  1. Analysis of biological tissues by Moessbauer spectroscopy

    Bonkova, I.; Bujdos, M.; Miglierini, M.

    2016-01-01

    The aim of this work was to analyze of biological tissues by Moessbauer spectroscopy in terms of demonstration of the magnetic properties of iron and its structural positions. Lyophilized samples of the human brain, human and equine spleen were used for the analysis. The samples were measured with 57 Fe Moessbauer spectroscopy in transmission arrangement at room temperature (∼ 300 K) and at a temperature of liquid helium (4.2 K). The resulting Moessbauer spectra measured at room temperature had doublet character, which confirms the presence of non-magnetic particles. On the contrary, low-temperature measurements are a superposition of several sextet and one duplicate. Hyperfine parameters obtained are similar to those reported hematite, ferrihydrite or magnetite. (authors)

  2. Moessbauer Studies of Volhynian Basalts

    Bakun-Czubarow, N.; Milczarski, J.; Galazka-Friedman, J.; Szlachta, K.; Forder, S.

    2011-01-01

    The Volhynian basalts studied belong to the effusive-tuffogenic Volhynian Series (Slawatycze Series in Poland), being the large Ediacaran continental igneous province, that covers an area of 200 000 km 2 in the western margin of East European Craton. The series is underlain by the Cryogenian terrigenous Polesie Series with doleritic sills and dikes. The Volhynian Series consists of the rock beds belonging to the three volcanic cycles with different ratios of flood basalts to pyroclastics. The aim of the study was recognition of primary and secondary Fe-bearing minerals, particularly Fe- and Fe-Ti oxides as well as determination of iron oxidation state, that is an important tool in the search for native copper deposits in these rocks. For Moessbauer studies the following rock samples were chosen: the Polesie Series dolerites, the Volhynian Series basalts from the Ukrainian quarries and drill-holes, e.g. from the Volodymir Volhynskaya drilling hole; the Slawatycze Series basalts from Kaplonosy drill-hole in Poland. In the Kaplonosy basalts the content of magnetite decreases with depth, which may be caused by magma differentiation due to fractional crystallization, when Mg content decreases as Ti and Fe - increases in basic magma. In the Kaplonosy basalts the Fe 2+ /Fe 3+ ratio increases with depth, which points to the increase of iron oxidation with the progress of basaltic magma differentiation. (authors)

  3. Clinical impact of body mass index on prostate biopsy in patients with intermediate PSA levels

    Sekita, Nobuyuki; Chin, Kensei; Fujimura, Masaaki; Mikami, Kazuo; Suzuki, Hiroyoshi; Kamijima, Shuichi

    2008-01-01

    From April 2005 to September 2007, 480 patients underwent transrectal prostate biopsy at our institution. The clinical data including age, serum prostate specific antigen (PSA) level, prostate volume and body mass index (BMI) were obtained, and the cancer detection rates and pathological findings were evaluated in 305 cases with a PSA concentration of 4.0 to 10.0 ng/ml. Prostate volume was calculated from magnetic resonance imaging (MRI) findings. The 305 patients were categorized according to their BMI into three groups (normal, less than 22 kg/m 2 ; overweight, 22-25 kg/m 2 ; and obese, more than 25 kg/m 2 ). Cancer detection rates and histopathologic findings were compared between the groups. Multivariate logistic regression analysis was also performed. Prostate cancer was detected in 127 patients. No significant differences in BMI were observed between biopsy-positive and biopsy-negative cases (p=0.965), and the detection rates of prostate cancer observed in the three groups were not significantly different. There was a significant association between BMI and the findings of high Gleason score (more than 4+3) (p=0.048). BMI was not a contributory factor of prostate cancer detection for cases with intermediate PSA levels; however, patients with high BMI may have high-grade malignancy features. (author)

  4. Development of the remediation strategy for the Dounreay intermediate level waste shaft

    McWhirter, A.F.

    1998-01-01

    The development of Fast Reactor Technology within the United Kingdom began in the mid 1950's and continued until 1994. It was concentrated at the United Kingdom Atomic Energy Authority site at Dounreay on the north coast of Scotland. During the construction of the site's low level liquid effluent discharge facility, a vertical access shaft was constructed which, when the discharge facility was completed, was sealed at the seaward end and allowed to fill naturally with water. It was then licensed by the Scottish Office Environmental Department as a disposal facility for what is now categorized as Intermediate Level Waste (ILW). Waste was disposed of to this facility from 1959 until 1977 when a hydrogen explosion in the air space above the shaft took place causing damage to the head works. Since that time UKAEA has maintained the shaft in a state of care and maintenance pending a decision on its long term future. During 1996 and 1997 detailed option studies were carried out which demonstrated that retrieval of the waste from the shaft and its subsequent above ground repackaging, conditioning and storage, represented the Best Practicable Environmental Option and UKAEA made this recommendation to the UK Government in November 1997. This recommendation was accepted by Government and, as a result, the present project to retrieve material has now begun. This paper describes the history of the facility, the options explored and the decision process by which the final strategy was determined. (author)

  5. Siting Criteria for Low and Intermediate Level Radioactive Waste Disposal in Egypt (Proposal approach)

    Abdellatif, M.M.

    2012-01-01

    The objective of radioactive waste disposal is to isolate waste from the surrounding media so that it does not result in undue radiation exposure to humans and the environment. The required degree of isolation can be obtained by implementing various disposal methods and suitable criteria. Near surface disposal method has been practiced for some decades, with a wide variation in sites, types and amounts of wastes, and facility designs employed. Experience has shown that the effective and safe isolation of waste depends on the performance of the overall disposal system, which is formed by three major components or barriers: the site, the disposal facility and the waste form. The site selection process for low-level and intermediate level radioactive waste disposal facility addressed a wide range of public health, safety, environmental, social and economic factors. Establishing site criteria is the first step in the sitting process to identify a site that is capable of protecting public health, safety and the environment. This paper is concerning a proposal approach for the primary criteria for near surface disposal facility that could be applicable in Egypt.

  6. Solidification of intermediate level liquid waste - ILLW, CEMEX waste form qualification

    D'Andrea, V.; Guerra, M.; Pancotti, F.; Maio, V.

    2015-01-01

    In the Sogin EUREX Facility about 125 m 3 of intermediate level radioactive waste and about 113 m 3 of low level radioactive waste, produced during the re-processing of MTR and CANDU fuel, are stored. Solidification of these wastes is planned in order to fulfill the specific requirements established by the Safety Authority, taking into account the criteria set up in a Technical Guide on the issue of radioactive waste management. The design of a cementation plant (CEMEX) of all liquid radioactive wastes is currently ongoing. The process requires that the liquid waste is neutralized with NaOH (NaOH 19 M) and metered into 440 liter drum together with the cement, while the mixture is stirred by a lost paddle ('in drum mixing process'). The qualification of the Waste Form consists of all the activities demonstrating that the final cemented product has the minimum requirements (mechanical, chemical and physical characteristics) compliant with all the subsequent management phases: long-term interim storage, transport and long-term disposal of the waste. All tests performed to qualify the conditioning process for immobilizing first extraction cycle (MTR and CANDU) and second extraction cycle liquid wastes, gave results in compliance with the minimum requirements established for disposal

  7. Design perspectives for the low and intermediate level radioactive waste repository in Korea

    Kim, Young Ki; Koh, Kwang Hoon; Lee, Sang Sun; Lee, Byung Sik; Choi, Gi Won

    2007-01-01

    The underground waste repository is located at Gyeongju and is designed for the disposal of all the Low- and Intermediate Level Radioactive Waste(LILW). It is scheduled to commence operations in the beginning of 2009. The repository, with a disposal capacity of 800,000 drums, will be constructed in granite rock near the seashore at the Gyeongju site. The repository will be designed to be constructed in phases to reach its final capacity 800,000 drums. In the first phase of construction, the repository will have a capacity to store 100,000 drums. The repository will house all LILW generated in the Republic of Korea. The first phase of the repository design consists of an assess shaft, a construction tunnel, an operating tunnel, an unloading tunnel, and six(6) silos. The silos are located at 80 to 130 meters below Mean Sea level (MSL), in bedrock. Each silo is 24.8m in diameter and 52.4m in height. The silo will be reinforced with concrete lining for rock supports which will also act aas an engineered barrier in limiting radioactive nuclide release aft closure. After serving its intended function the repository will be filled and sealed. The primary objective of filling and sealing is to prevent ground water flow into the silo through the tunnel system and to prevent inadvertent intrusion into the repository after closure

  8. Interstitial diffusion in crystal and the Moessbauer effect

    Dzyublik, A.Ya.

    1976-01-01

    The role of different vibrational states of a crystal is taken into account in the model of interstitial uncorrelated jumps. The relation of the diffusion coefficient for an interstitial with probabilities of jumps is found. The cross section for resonant absorption of γ-quanta by a nucleus of a diffusing atom in a crystal is calculated. The existence of vibrational levels is shown to lead to less broadening and intensity of the Moessbauer line than those predicted by the simple model of jumps. The absorption line shape for atom jumping through octahedral sites in bcc lattice is investigated [ru

  9. Prestudy of final disposal of long-lived low and intermediate level waste

    Wiborgh, M [ed.; Kemakta Konsult AB., Stockholm (Sweden)

    1995-01-01

    The repository for long-lived low and intermediate level waste, SFL 3-5, is foreseen to be located adjacent to the deep repository for spent encapsulated fuel, SFL 2. The SFL 3-5 repository comprises of three repository parts which will be used for the different categories of waste. In this report the work performed within a pre-study of the SFL 3-5 repository concept is summarised. The aim was to make a first preliminary and simplified assessment of the near-field as a barrier to radionuclide dispersion. A major task has been to compile information on the waste foreseen to be disposed of in SFL 3-5. The waste comprises of; low and intermediate level waste from Studsvik, operational waste from the central interim storage for spent fuel, CLAB, and the encapsulation plant, decommissioning waste from these facilities, and core components and internal parts from the reactors. The total waste volume has been estimated to about 25000 m{sup 3}. The total activity content at repository closure is estimated to be about 1 {center_dot}10{sup 17} Bq in SFL 3-5. At repository closure the short-lived radionuclides, for example Co-60 and Fe-55, have decayed considerably and the activity is dominated by nickel isotopes in the metallic waste from the reactors, to be disposed of in SFL 5. However, other radionuclides may be more or equally important from a safety point of view, e.g cesium-isotopes and actinides which are found in largest amounts in the SFL 3 waste. A first evaluation of the long term performance or the SFL 3-5 repository has been made. A systematic methodology for scenario formulation was tested. The near-field release of contaminants was calculated for a selected number of radionuclides and chemo-toxic elements. The radionuclide release calculations revealed that Cs-137 and Ni-63 would dominate the annual release from all repository parts during the first 1000 years after repository closure and that Ni-59 would dominate at longer times.

  10. Prestudy of final disposal of long-lived low and intermediate level waste

    Wiborgh, M.

    1995-01-01

    The repository for long-lived low and intermediate level waste, SFL 3-5, is foreseen to be located adjacent to the deep repository for spent encapsulated fuel, SFL 2. The SFL 3-5 repository comprises of three repository parts which will be used for the different categories of waste. In this report the work performed within a pre-study of the SFL 3-5 repository concept is summarised. The aim was to make a first preliminary and simplified assessment of the near-field as a barrier to radionuclide dispersion. A major task has been to compile information on the waste foreseen to be disposed of in SFL 3-5. The waste comprises of; low and intermediate level waste from Studsvik, operational waste from the central interim storage for spent fuel, CLAB, and the encapsulation plant, decommissioning waste from these facilities, and core components and internal parts from the reactors. The total waste volume has been estimated to about 25000 m 3 . The total activity content at repository closure is estimated to be about 1 ·10 17 Bq in SFL 3-5. At repository closure the short-lived radionuclides, for example Co-60 and Fe-55, have decayed considerably and the activity is dominated by nickel isotopes in the metallic waste from the reactors, to be disposed of in SFL 5. However, other radionuclides may be more or equally important from a safety point of view, e.g cesium-isotopes and actinides which are found in largest amounts in the SFL 3 waste. A first evaluation of the long term performance or the SFL 3-5 repository has been made. A systematic methodology for scenario formulation was tested. The near-field release of contaminants was calculated for a selected number of radionuclides and chemo-toxic elements. The radionuclide release calculations revealed that Cs-137 and Ni-63 would dominate the annual release from all repository parts during the first 1000 years after repository closure and that Ni-59 would dominate at longer times

  11. Millennial total sea-level commitments projected with the Earth system model of intermediate complexity LOVECLIM

    Goelzer, H; Huybrechts, P; Raper, S C B; Loutre, M-F; Goosse, H; Fichefet, T

    2012-01-01

    Sea-level is expected to rise for a long time to come, even after stabilization of human-induced climatic warming. Here we use simulations with the Earth system model of intermediate complexity LOVECLIM to project sea-level changes over the third millennium forced with atmospheric greenhouse gas concentrations that stabilize by either 2000 or 2100 AD. The model includes 3D thermomechanical models of the Greenland and Antarctic ice sheets coupled to an atmosphere and an ocean model, a global glacier melt algorithm to account for the response of mountain glaciers and ice caps, and a procedure for assessing oceanic thermal expansion from oceanic heat uptake. Four climate change scenarios are considered to determine sea-level commitments. These assume a 21st century increase in greenhouse gases according to SRES scenarios B1, A1B and A2 with a stabilization of the atmospheric composition after the year 2100. One additional scenario assumes 1000 years of constant atmospheric composition from the year 2000 onwards. For our preferred model version, we find an already committed total sea-level rise of 1.1 m by 3000 AD. In experiments with greenhouse gas concentration stabilization at 2100 AD, the total sea-level rise ranges between 2.1 m (B1), 4.1 m (A1B) and 6.8 m (A2). In all scenarios, more than half of this amount arises from the Greenland ice sheet, thermal expansion is the second largest contributor, and the contribution of glaciers and ice caps is small as it is limited by the available ice volume of maximally 25 cm of sea-level equivalent. Additionally, we analysed the sensitivity of the sea-level contributions from an ensemble of nine different model versions that cover a large range of climate sensitivity realized by model parameter variations of the atmosphere–ocean model. Selected temperature indices are found to be good predictors for sea-level contributions from the different components of land ice and oceanic thermal expansion after 1000 years. (letter)

  12. Approximation of Moessbauer spectra of metallic glasses

    Miglierini, M.; Sitek, J.

    1988-01-01

    Moessbauer spectra of iron-rich metallic glasses are approximated by means of six broadened lines which have line position relations similar to those of α-Fe. It is shown via the results of the DISPA (dispersion mode vs. absorption mode) line shape analysis that each spectral peak is broadened owing to a sum of Lorentzian lines weighted by a Gaussian distribution in the peak position. Moessbauer parameters of amorphous metallic Fe 83 B 17 and Fe 40 Ni 40 B 20 alloys are presented, derived from the fitted spectra. (author). 2 figs., 2 tabs., 21 refs

  13. Moessbauer study of iron(III) salicylates

    Mahesh, K; Sharma, N D; Gupta, D C [Kurukshetra Univ. (India). Dept. of Physics; Puri, D M [Kurukshetra Univ. (India). Dept. of Chemistry

    1979-07-01

    Moessbauer infrared and magnetic studies of different basic salicylates of iron(III) are reported. Comparison of observed isomer shift and quadrupole splitting with the earlier work allows to assign the trinuclear chain structure to the complexes wherein the central iron atom in the chain is considered to be octahedrally coordinated in case of salicylate and 4-aminosalicylate derivatives, and pentacoordinated for the thiosalicylate with the terminal iron atom in tetrahedral symmetry. The Moessbauer parameters and ..mu..sub(eff)-value indicate the high spin state of the central iron atom and low spin state for the terminal ones.

  14. Moessbauer firing study of Peruvian clays

    Salazar, R.; Wagner, U.; Wagner, F.E.

    1983-01-01

    In connection with work on ancient ceramics Moessbauer studies of the firing behaviour of six Peruvian clays have been performed in oxidizing and reducing atmospheres. For two clays, one of them is poor, the other one is rich in oxides, the change of the Moessbauer parameters on firing between 100 and 1350 0 C was measured in detail, both with and without preceding reduction. The minerals present at characteristic temperatures are determined by X-ray diffraction and an attempt is made to discuss the physical and chemical processes occurring in the different temperature ranges. (author)

  15. Chemical aspects of 237 Np Moessbauer spectroscopy

    Karraker, D.G.

    1984-01-01

    The 237 Np Moessbauer effect has been especially useful in studies of neptunium chemistry, by virtue of its excellent resolution and straightforward experimental techniques. Neptunium can have valences from +3 to +7, and a broad range of compounds can be prepared that are analogous to those of other actinide elements. Studies on neptunium compounds, for example, have a ready application to the analogous compounds of uranium and plutonium. The emphasis in this paper will be on the application of the 237 Np Moessbauer effect to problems in neptunium chemistry

  16. Evaluation of low and intermediate level radioactive solidified waste forms and packages

    1990-10-01

    Evaluation of low and intermediate level radioactive waste forms and packages with respect to compliance with quality and safety requirements for transport, interim storage and disposal has become a very important part of the radioactive waste management strategy in many countries. The evaluation of waste forms and packages provides precise basic data for regulatory bodies to establish safety requirements, and implement quality control and quality assurance procedures for radioactive waste management programmes. The requirements depend very much upon the disposal option selected, treatment technology used, waste form characteristics, package quality and other factors. The regulatory requirements can also influence the methodology of waste form/package evaluation together with selection and analysis of data for quality control and safety assurance. A coordinated research programme started at the end of 1985 and brought together 12 participants from 11 countries. The results of the programme and each particular project were discussed at three Research Coordination Meetings held in Cairo, Egypt, in May, 1986; in Beijing, China, in April, 1998; and at Harwell Laboratory, United Kingdom, in November, 1989. This document summarises the salient features and results achieved during the four year investigation and a recommendation for future work in this area. Refs, figs and tabs

  17. Corrosion susceptibility of steel drums containing cemented intermediate level nuclear wastes

    Duffó, Gustavo S.; Farina, Silvia B.; Schulz, Fátima M.; Marotta, Francesca

    2010-10-01

    Cementation processes are used as immobilization techniques for low or intermediate level radioactive waste for economical and safety reasons and for being a simple operation. In particular, ion-exchange resins commonly used for purification of radioactive liquid waste from nuclear reactors are immobilized before being stored to improve the leach resistance of the waste matrix and to maintain mechanical stability. Combustible solid radioactive waste can be incinerated and the resulting ashes can also be immobilized before storage. The immobilized resins and ashes are then contained in steel drums that may undergo corrosion depending on the presence of certain contaminants. The work described in this paper was aimed at evaluating the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins and incineration ashes containing different concentrations of aggressive species (mostly chloride and sulphate ions). A special type of specimen was designed to simulate the cemented waste in the drum. The evolution of the corrosion potential and the corrosion current density of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 1 year. The results show the deleterious effect of chloride on the expected lifespan of the waste containers.

  18. Corrosion susceptibility of steel drums to be used as containers for intermediate level nuclear waste

    Farina, S.; Schulz Rodriguez, F.; Duffó, G.

    2013-07-01

    The present work is a study of the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins contaminated with different types and concentrations of aggressive species. A special type of specimen was manufactured to simulate the cemented ion-exchange resins in the drum. The evolution of the corrosion potential and the corrosion rate of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 900 days. The aggressive species studied were chloride ions (the main ionic species of concern) and sulphate ions (produced during radiolysis of the cationic exchange-resins after cementation). The work was complemented with an analysis of the corrosion products formed on the steel in each condition, as well as the morphology of the corrosion products. When applying the results obtained in the present work to estimate the corrosion depth of the steel drumscontaining the cemented radioactive waste after a period of 300 years (foreseen durability of the Intermediate Level Radioactive Waste facility in Argentina) , it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums.

  19. Corrosion susceptibility of steel drums containing cemented intermediate level nuclear wastes

    Duffo, Gustavo S.; Farina, Silvia B.; Schulz, Fatima M.; Marotta, Francesca

    2010-01-01

    Cementation processes are used as immobilization techniques for low or intermediate level radioactive waste for economical and safety reasons and for being a simple operation. In particular, ion-exchange resins commonly used for purification of radioactive liquid waste from nuclear reactors are immobilized before being stored to improve the leach resistance of the waste matrix and to maintain mechanical stability. Combustible solid radioactive waste can be incinerated and the resulting ashes can also be immobilized before storage. The immobilized resins and ashes are then contained in steel drums that may undergo corrosion depending on the presence of certain contaminants. The work described in this paper was aimed at evaluating the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins and incineration ashes containing different concentrations of aggressive species (mostly chloride and sulphate ions). A special type of specimen was designed to simulate the cemented waste in the drum. The evolution of the corrosion potential and the corrosion current density of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 1 year. The results show the deleterious effect of chloride on the expected lifespan of the waste containers.

  20. Long-lived high and intermediate level radioactive wastes: defining the context, stakes and perspectives

    2006-01-01

    The French law from December 30, 1991 has defined an ambitious 15 years program of researches in order to explore the different possible paths for the long-term management of long-lived high and intermediate level radioactive wastes. The law foresees also that at the end of the 15 years research program, a project of law will be prepared by the French government and transmitted to the European parliament in 2006. A public debate has been organized and emceed in 2005 in order dialogue with the general public and to gather its questions, remarks and fears. In the framework of their contribution to this debate, the ministries of industry and environment have prepared this document which answers some key questions about radioactive waste management: where do wastes come from, what are the risks, how are they managed today in France and in foreign countries, what are the results of the researches carried out during 15 years, what are the advantages and drawbacks of each waste management solution considered, what is the perspective of application of each solution, what is the position of experts, what will be the decision process. This synthetic document supplies some reference marks to better understand these different points. Some pedagogical files about radioactivity, fuel cycle, and nuclear industry activities are attached to the document. (J.S.)

  1. Environmental assessment for OPG's deep geologic repository for low and intermediate level waste

    Barker, D.; Rawlings, M.; Beal, A.

    2011-01-01

    The environmental assessment process for the Deep Geologic Repository (DGR) Project was initiated very early in the planning stages. Feasibility studies were initiated in 2003, after Ontario Power Generation (OPG) and the Municipality of Kincardine signed a Memorandum of Understanding agreeing to assess options for long-term management of low and intermediate level waste (L and ILW) options at the Bruce nuclear site. The location of the DGR, in the Municipality of Kincardine, is based on a willing and informed host community. The preferred approach, the DGR at the Bruce nuclear site, was advanced based on results of feasibility studies which looked at a number of options for long-term management of L&ILW and support from the local community and their elected representatives. The federal environmental assessment of the project was initiated following the signing of a Host Community Agreement and completion of a telephone poll, the results of which indicated that the majority of Municipality of Kincardine residents support the project. The environmental assessment began in 2006 as a comprehensive study and was ultimately referred to a joint review panel process in 2009. The environmental assessment considers the potential near-term effects of the construction and operations of the proposed project. Because of the nature of the project, the assessment of effects also considers long-term effects extending out to the million year time-frame, including effects of climate change, glaciations and seismic activity. (author)

  2. Corrosion susceptibility of steel drums to be used as containers for intermediate level nuclear waste

    Farina, S.; Schulz Rodriguez, F.; Duffo, G.

    2013-01-01

    The present work is a study of the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins contaminated with different types and concentrations of aggressive species. A special type of specimen was manufactured to simulate the cemented ion-exchange resins in the drum. The evolution of the corrosion potential and the corrosion rate of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 900 days. The aggressive species studied were chloride ions (the main ionic species of concern) and sulphate ions (produced during radiolysis of the cationic exchange-resins after cementation). The work was complemented with an analysis of the corrosion products formed on the steel in each condition, as well as the morphology of the corrosion products. When applying the results obtained in the present work to estimate the corrosion depth of the steel drums containing the cemented radioactive waste after a period of 300 years (foreseen durability of the Intermediate Level Radioactive Waste facility in Argentina), it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. (authors)

  3. The disposal of low and intermediate-level radioactive wastes: the Billingham anhydrite mine

    1983-10-01

    This document explains the role of NIREX (Nuclear Industry Radioactive Waste Executive) in planning for the safe disposal of low and intermediate-level radioactive wastes and outlines the plans for the investigation and possible development of a deep repository at ICI's disused anhydrite mine, Billingham. The site is conveniently located and the geology is well understood. The existing workings are known to have a long history of stability and of particular importance, very little water is present. The next step is for NIREX to undertake site investigations and assess in detail the site's suitability. On the basis of this assessment NIREX will either confirm its interest in the site or reject it as unsuitable. If the site proves to be adequate for the development of a deep repository then NIREX will seek the necessary planning approvals and authorisations for such a development. Converting the mine into a repository would involve construction of some new buildings at the surface although little or no new excavation work would be necessary. As far as possible existing road and rail networks would be used. In designing and operating any repository the safety of the public and the work-force will be of paramount importance. (author)

  4. Disposal of low- and intermediate-level solid radioactive wastes in rock cavities

    1983-01-01

    This Guidebook summarizes the factors to be considered and the activities to be undertaken in the overall planning and development of a disposal system for solid or solidified low- and intermediate-level wastes in rock cavities. Aspects related to repository site selection, design, construction, operation, shutdown, surveillance, regulation and safety assessment are discussed here in general terms. They will be covered in greater technical detail in a separate document. This report considers the emplacement of wastes in categories II, III, IV and V, as defined in Table 3.1, in different kinds of cavities located at various depths from just below the surface to deep continental rock. The choice of the type of cavity and its depth and of the disposal site itself is related to the radiological protection requirements for the wastes concerned. The repositories considered include natural caves and abandoned mines as well as specially excavated cavities in various geological formations. Consideration is also given to hydrogeological, environmental and societal factors. The guidelines given in the report are made sufficiently general to cover a broad variety of different circumstances. Consequently, the practical application of these guidelines needs a case-by-case consideration which takes into account the local conditions, e.g. natural circumstances, the characteristics of the wastes and national and international regulations and practices

  5. Study of the impact behaviour of packages containing intermediate level radioactive waste coming from nuclear installations

    Davis, D.; Lund, J.S.; Meredith, P.; Walker, P.; Wells, D.A.; Jowett, J.; Kinsella, K.

    1989-01-01

    The following describes primarily an experimental study into the benefits, for impact resistance, to be gained by incorporating a welded lid into the design of the cement filled drum type of intermediate level waste package. Tests on packages which were not provided with a lid showed that matrix material began to be expelled from drop heights of about 16m. This damage threshold was similar for packages composed of both high and low strength matrix. Above the damage threshold, however, the rate of increase of expelled mass with drop height was greater for the packages filled with a low strength matrix. Similar tests were conducted with specimens to which a lid had been attached by welding. Even from the greatest drop height available at the test facility (28m) only one package showed a significant amount of drum tearing but even then little matrix was lost. The benefits of incorporating a welded lid into package design were thus clearly established. Simple calculations were performed to predict the local deformations and deceleration/time histories of the packages. By optimisation of the impact resistive stress used in the computer model, final knockback areas were predicted to an accuracy of 30%. The average deceleration predicted for four of the six tests for which deceleration histories were available were also within 30% of measured values

  6. Feasibility study on vitrification of low- and intermediate-level radioactive waste from pressurized water reactors

    Park, J.K.; Song, M.J.

    1998-01-01

    In order to obtain annual generation volume and composition data for low- and intermediate-level radioactive waste (LILW), characteristics and generation trends for each waste which was produced at nuclear power plants (NPPs) in Korea were investigated. Of the three different types of melters, the platinum crucible was found to be most suitable for the performance of vitrification experiments and hence, was used to help better understand the optimal waste contents in borosilicate glass waste forms with respect to waste types. After the performance of vitrification experiments, compressive strength tests showed that the final waste glass product, containing up to 40 vol% of ashy pyrolyzed/oxidized at 400--800 C, showed good mechanical stability and homogeneity in the glass matrix. Economical assessment was performed with some considerations given for equipment having already been adopted for LILW treatment in Korea for four treatment strategies with melters selected from a technical assessment. For each strategy, the capital and the operation cost were estimated, and the disposal volume was calculated with reasonably estimated volume reduction factors with regard to waste type and treatment concept

  7. Storage and final disposal of low and intermediate level radioactive waste materials in Europe

    Plecas, I.

    1997-01-01

    As of the end of 1995, 18 countries in Europe had electricity-generating nuclear power reactors in operation or under construction. There are currently 217 operating units, with a total capacity of about 165 GW e. In addition, there are 26 units under construction, which would bring the total electrical generating capacity to about 190 GW e.The management of radioactive waste is not a new concept. It has been safely practised for low and intermediate level wastes for almost 40 years. Today, after decades of research, development and industrial applications, it can be stated confidently that safe technological solutions for radioactive waste management exist. However, waste disposal as a whole waste management system is no longer a matter for scientists but requires co-operation with politicians, licensing authorities, industry and ultimately general public. The goal is unique: the protection of human health and the global environment against possible short term and (very) long term effects of radioactive materials. Disposal of waste materials in a repository without the intention of retrieval, whereas storage, as previously discussed, is done with the intention that the waste will be retrieved at a later time. If disposed waste is abandoned, the repository site is not abandoned, but surveillance should not be necessary beyond some expected period of institutional control. (author)

  8. Iranian Language Teachers’ and Students’ Perspectives on Top Notch Series (2nd edition at Intermediate Level

    Mehdi Azadsarv

    2014-12-01

    Full Text Available As the means of transferring knowledge between teachers and students, coursebooks play a significant role in educational practices all over the world. Evaluation of coursebooks is also of great significance as it manages to a better understanding of the nature of a specific teaching/learning situation. The present study is an attempt to evaluateTop Notch coursebook from both Iranian EFL learners’ and teachers’ perspectives. One hundred students and 20 teachers participated in this study. Sixty four of the students and nine of the teachers were male and 36 of the students and 11 of the teachers were female. The range of teachers' experience of teaching the coursebook was between 2-4 years and the range of students' experience of studying the coursebook was between 1-3 years. The data collection took place in three language institutes of Gilan and Mazandaran provinces. The coursebook, evaluated based on modified version of Cunningsworth's (1995 checklist, was the intermediate level of Top Notch. It was evaluated by both students and teachers based on administering written questionnaires. In order to triangulate the gathered data, 25 percent of the teachers and 10 percent of the students attended an interview session. Data analysis indicated that strengths of Top Notch from teachers' perspective are grammar, visuals, supplementary materials and culture and from students' point of view are content, grammar, phonology and visuals.

  9. Longterm performance of structural component of intermediate- and low-level radioactive waste disposal facility

    Whang, J. H.; Kim, S. S.; Chun, T. H.; Lee, J. M.; Yum, M. O.; Kim, J. H.; Kim, M. S.

    1997-03-01

    Underground repository for intermediate- and low-level radioactive waste is to be sealed and closed after operation. Structural components, which are generally made of cement concrete, are designed and accommodated in the repository for the purpose of operational convenience and stability after closure. To forecast the change of long-term integrity of the structural components, experimental verification, using in-situ or near in-situ conditions, is necessary. Domestic and foreign requirements with regard to the selection criteria and the performance criteria for structural components in disposal facility were surveyed. Characteristics of various types of cement were studied. Materials and construction methods of structural components similar to those of disposal facility was investigated and test items and methods for integrity of cement concrete were included. Literature survey for domestic groundwater characteristics was performed together with Ca-type bentonite ore which is a potential backfill material. Causes or factors affecting the durability of the cement structures were summarized. Experiments to figure out the ions leaching out from and migrating into cement soaked in distilled water and synthetic groundwater, respectively, were carried out. And finally, diffusion of chloride ion through cement was experimentally measured

  10. The disposal of low and intermediate-level radioactive wastes: the Elstow Storage Depot

    1983-10-01

    This document explains the role of NIREX (Nuclear Industry Radioactive Waste Executive) in planning for the safe disposal of low and intermediate-level radioactive wastes and outlines the plans for the investigation and possible development of a new shallow repository at the CEGB's Elstow Storage Depot, Bedfordshire. The site is conveniently located and is situated on a suitable geologic formation, the Oxford Clay. The next step is for NIREX to undertake site investigations and assess in detail the site's suitability. On the basis of this assessment NIREX will either confirm its interest in the site or reject it as unsuitable. If the site proves to be adequate for the development of a shallow repository then NIREX will seek the necessary planning approvals and authorisations for such a development. The development would involve the construction of new buildings and a programme of trench excavation, waste positioning and trench closure. Existing tenants at the Depot will be accommodated as far as possible. The existing road and rail networks would be used for delivering the packaged wastes. In designing and operating any repository the safety of the public and workforce, both now and in the future, will be of paramount importance. (author)

  11. An evaluation on the disposal alternatives for low- and intermediate- level radwaste (II)

    Park, Hun Hwee; Han, Kyung Won; Hahn, Pil Soo; Lee, Han Soo; Cho, Won Jin; Lee, Jae Dwan; Park, Chung Kyun; Lee, Myung Joo; Choi, Heui Joo; Lee, Youn Myoung

    1988-02-01

    An evaluation on the radioactive waste disposal alternatives for the low-and intermediate level wastes being produced from nuclear power generation and radioisotope application was carried out in view of the radiological safety, socio-political aspects and repository construction economics. Three types of possible alternatives-sample shallow land disposal method, engineered shallow land disposal method and engineered rock cavern disposal method are investigated. The safety assessment consists of radiological dose calculation and nonradiological impacts which is expressed as total number of injuries and fatalities during construction, operation and transportation. The sociopolitical assessment is done in terms of site conditions including easiness for land acquisition, technical feasibility and public acceptance. The economic assessment is performed by cost comparison regarding land acquisition, construction, operation and closure for each alternatives. The evaluation shows that engineered rock cavern disposal method has remarkable favour in safety than others. And also an integrated evaluation using AHP results the engineered rock cavern disposal method as the most favorable option

  12. Aube's storage centre for low and intermediate level wastes: Annual report 2008

    2008-01-01

    After a presentation of the ANDRA (the French national Agency for radioactive waste management), its missions, its facilities, and its financing, this report reviews the activity of its storage centre for low and intermediate level wastes located on the territory of three towns in the Aube district. It briefly describes the facilities, the different categories of liquid effluents and their associated networks. It indicates some important figures characterizing the centre's operation. It describes the main safety objectives, technical measures and results in terms of radioprotection. It reports the main events in the relationship with the safety authority. It also briefly describes the incidents and accidents which occurred in 2008. It presents and specifies some results of the numerous environmental analyses performed around the centre (radioactivity measurements in air, water, milk, mushrooms, fishes, and so on), comments the radiologic impact of releases, and actions to improve these results. It gives assessments of the amount of produced wastes and describes their processing and management. Information actions are presented and the CHSCT (Committee of hygiene, safety, and working conditions) are reported

  13. Prototype of thermal degradation for radioactive wastes of low and intermediate level

    Diaz A, L.V.; Pacheco S, J.O.; Pacheco P, M.; Monroy G, F.; Emeterio H, M.

    2005-01-01

    At the present time, the scientific, academic, industrial and technological activities, generate great quantity of radioactive wastes of low and intermediate level (DRNBI). For to assure an appropriate final disposal of these, it is intended their treatment and vitrification by means of thermal plasma. This alternative offers multiple advantages in an only process: elevated energy density (105W/cm 3 ), high enthalpy (1400 kJ/mol), elevated chemical reactivity, quick quenching (106K/s) and operation temperatures of 4000 to 15000K; this allows the treatment of a great diversity of waste. Those reactors are compact and they work to atmospheric pressure and reduced thermal inertia. This technology allows to degrade DRNBI and to contain them in a vitreous matrix by means of a system made up of a reactor, canyon of plasma, of monitoring, of washing of gases and of control. Besides the design and general characteristics of the Prototype of Thermal Degradation of DRNBI, they are reported in this work the advances achieved in the selection of the ceramic material for the vitrification. Their characterization was carried out by means of SEM and XRD. With the preliminary results it can discern that the material but appropriate to be used as vitreous matrix is a ceramic clay. With the development of the proposed technology and the material for the vitreous matrix, it will be to treat DRNBI. (Author)

  14. A successful case site selection for low-and intermediate-level radioactive waste disposal facility

    Lee, Bongwoo

    2007-01-01

    Korea decided on Gyeongju-si as the site of low-and intermediate-level radioactive waste disposal facility by referendum in November, 2005. Five success factors are considered; 1) the mayor and municipal assembly leaded the public opinion of inhabitants, 2) an invitation group was formed by citizen, social and religious group, 3) Gyeongju-si has operated the nuclear power plant since 20 years ago, and this radioactive waste disposal facility brings large financial support, 4) many kinds of public information means were used for invitation agreement and 5) the preconception, a nuclear facility is danger, was removed by visiting citizen, social group and local inhabitants at the nuclear power plant facility. Promotion process of the project, invitation process of Gyeongju-si and success factors, construction of an invitation promotion group and development of public information activities, publicity of financial effects and safety of radioactive waste disposal facility, increase of general acceptance among inhabitants by many kinds of public information means, and P.R. of safety of nuclear power plant facility by visiting leadership layers are reported. (S.Y.)

  15. Corrosion on reinforced concrete structures. An application for the intermediate level radioactive waste container

    Arva, Alejandro; Alvarez, Marta G.; Duffo, Gustavo S.

    2003-01-01

    The behavior of steel reinforcement bars (rebars) for a high performance reinforced concrete made of sulfate resistant portland cement was evaluated from the rebars corrosion point of view. The results from the present work will be used to evaluate the materials properties to be used in the construction of the intermediate level radioactive waste disposal containers. The study is carried out evaluating the incidence of chloride and sulfate ions, as well as, concrete carbonation in the rebar corrosion process. The electrochemical parameters that characterize the corrosion process (corrosion potential [E corr ], polarisation resistance [Rp] and concrete electrical resistivity [ρ]) were monitored on specially designed reinforced concrete specimens. The results up to date (about 1000 days of exposure) reveal that the concrete under study provides to the steel reinforcement bars of a passive state against corrosion under the test conditions. An increasing tendency as a function of time of ρ is observed that corroborates the continuous curing process of concrete. The chloride and carbonation diffusion coefficients were also determined, and their values are comparable with those of high quality concrete. (author)

  16. Disposal of low- and intermediate-level solid radioactive wastes in rock cavities. A guidebook

    1983-01-01

    This Guidebook summarizes the factors to be considered and the activities to be undertaken in the overall planning and development of a disposal system for solid or solidified low- and intermediate-level wastes in rock cavities. Aspects related to repository site selection, design, construction, operation, shutdown, surveillance, regulation and safety assessment are discussed here in general terms. They will be covered in greater technical detail in a separate document. This report considers the emplacement of wastes in categories II, III, IV and V, as defined in Table 3.1, in different kinds of cavities located at various depths from just below the surface to deep continental rock. The choice of the type of cavity and its depth and of the disposal site itself is related to the radiological protection requirements for the wastes concerned. The repositories considered include natural caves and abandoned mines as well as specially excavated cavities in various geological formations. Consideration is also given to hydrogeological, environmental and societal factors. The guidelines given in the report are made sufficiently general to cover a broad variety of different circumstances. Consequently, the practical application of these guidelines needs a case-by-case consideration which takes into account the local conditions, e.g. natural circumstances, the characteristics of the wastes and national and international regulations and practices.

  17. Deconvolution of Moessbauer spectra using Voigt functions; Deconvolucion de espectros Moessbauer empleando funciones Voigt

    Flores Ll, H J

    1990-08-15

    The form of the resonance line in Moessbauer spectroscopy is a form of Lorentzian line, but this form of line it enlarges due to several effects: finite thickness of the absorber, instrumental instability, diffusion of Co{sup 57} in crystals and fluctuations in the environment of the emitting nucleus. To take into account this effects it has been used as form of line in Moessbauer spectroscopy the Voigt function that is the convolution of a Lorentzian and a Gaussian. (Author)

  18. Project Guarantee 1985. Final repository for low- and intermediate level radioactive wastes: Safety report

    Anon.

    1985-01-01

    Storage of radioactive waste must delay the return of radionuclides to the biosphere for a long period of time and must maintain the release rates at a sufficiently low level for all time. This is achieved with the aid of a series of safety barriers which consist, on the one hand, of technical barriers in the repository and, on the other hand , of natural geological barriers as they occur at the repository location. In order to assess the efficiency of the barriers, the working methods of the technical barriers and the host rock must be understood. This understanding is transferred into quantitative models in order to calculate the safety of the repository. The individual barriers and the methods used to modelling their functions were described in volume NGB 85-07 of the Project Guarantee 1985 report series and the data necessary for modelling were given. The models and data are used in the safety analysis, the results of which are contained in the present report. Safety considerations show that models are available in Switzerland which allow, in principle, an assessment of the long-term behaviour of a repository for low- and intermediate-level waste. The evaluation of earlier studies and experimental work, suitable laboratory measurements and results from field research enable compilation of a representative data-set so that the requirements for quantitative statements on safety of final disposal are met from this side also. The safety calculations show that the radiation doses calculated for a base case scenario with realistic/conservative parameter values are negligibly low. Also, radiation doses which are clearly under the protection standard of 10 mrem per year result for conservative values and the cumulation of several conservative assumptions. Even assuming exposure of the repository by erosion, a radiotoxicity of the soil formed results which is under natural values

  19. Development and evaluation of an intermediate-level elective course on medical Spanish for pharmacy students.

    Mueller, Robert

    The Spanish-speaking population in the United States is increasing rapidly, and there is a need for additional educational efforts, beyond teaching basic medical Spanish terminology, to increase the number of Spanish-speaking pharmacists able to provide culturally appropriate care to this patient population. This article describes the development and evaluation of an intermediate-level elective course where students integrated pharmacy practice skills with Spanish-language skills and cultural competency. Educational Activity and Setting: Medical Spanish for Pharmacists was developed as a two-credit elective course for pharmacy students in their third-professional-year who possessed a certain level of Spanish language competence. The course was designed so that students would combine patient care skills such as obtaining a medication list and providing patient education, and pharmacotherapy knowledge previously learned in the curriculum, along with Spanish-language skills, and apply them to simulated Spanish-speaking patients. Elements to promote cultural competency were integrated throughout the course through a variety of methods, including a service learning activity. Successful attainment of course goals and objectives were demonstrated through quizzes, assignments, examinations, and an objective structured clinical examination (OSCE). Based on these course assessments, students performed well during both offerings of the course. While the class cohort size was small in the two offerings of the course, the Medical Spanish for Pharmacists elective may still serve as an example for other pharmacy programs as an innovative approach in combining Spanish language, specific pharmacy skills, cultural competency, and service learning. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Development of geopolymers as candidate materials for low/intermediate level highly alkaline nuclear waste

    Perera, D.S.; Vance, E.R.; Kiyama, S.; Aly, Z.; Yee, P.

    2006-01-01

    Full text: Geopolymers have been studied for many years as a possible improvement on cement in respect of compressive strength, resistance to fire, heat and acidity, and as a medium for the encapsulation of hazardous or low/ intermediate level radioactive waste. They are made by adding aluminosilicates to concentrated alkali solutions and the application of heat at 0 Cfor subsequent polymerisation. In this work we studied them as suitable candidate materials to incorporate NaOH/NaA10 2 containing waste with low levels of Cs, Sr and Nd. Geopolymers were produced by incorporating the highly alkaline solution as part of the composition with added metakaolinite, fumed silica and extra NaOH, such that the overall geopolymer composition was of molar ratios Si/Al = 2 and Na/Al = 1. The simulated waste contained Na2SO 4 , therefore Ba(OH) 2 was also added to precipitate the SO 4 x 2 as BaSO 4 . Three geoplymers of the same composition containing simulated wastes were leach tested in triplicate after heating at 400 0 Cfor 1 h (to remove -98% of free and interstitial water) under the PCT-B test protocol at 90 0 Cfor 7 days and their results are listed in Table 1. The Cs, Sr and Nd normalised leach rates were low. The Na leach rate was ∼ 4 g/L thus passing the PCT-B test protocol value of 13.5 g/L for EA glass. The X-ray diffraction and scanning electron microscopy showed that BaS04 did precipitate, however all the S did not appear to have precipitated. The ANSI/ANS-16.1-2003 test was carried out on the above geopolymer composition for 5 days. The ANSI Leachability Index D (diffusivity of 10''cm sec'') for the elements released are listed in Table 2. A Portland cement was also tested for comparison and the Leachability index values are 11, 8 and 10 for Al, Na and Ca respectively. Both passed the test protocol insofar as they were > 6. Geopolymers thus passing the tests for high level nuclear waste glass (PCT-B) and for low level nuclear waste (ANSI) show promising potential

  1. Polarized Moessbauer transitions in mixed hyperfine interactions

    Barb, D.; Tarina, D.

    1975-01-01

    A contribution to the theory of elliptical polarization in the Moessbauer effect for transitions between mixed nuclear states is reported. A relation between the two-dimensional complex vector parameterization and the photon polarization density matrix was used in describing changes in the polarization of the gamma-ray involved. (A.K.)

  2. A Moessbauer spectrometer for difficult isotopes

    Cranshaw, T.E.

    1981-06-01

    The parameters of some Moessbauer isotopes present experimental difficulties either because high velocities, low frequencies, low temperatures, or any combination of these conditions, are needed. A simple approach to easing these difficulties is described, using a mechanical resonant system and a phase locked loop. (author)

  3. Moessbauer Studies in Chinese Archaeology: A Review

    Hsia Yuanfu; Huang Hongbo

    2003-01-01

    The Moessbauer effect has been applied to a wide variety of objects related to Chinese archaeology. Besides ceramic artifacts, materials like porcelain, glazes, bronzes, ancient coins, ancient mineral drugs, and even fossils were studied. This article reviews these applications with particular emphasis on the study of the famous terracotta warriors and horses of the Qin Dynasty.

  4. Absorber transmissivities in 57Fe Moessbauer spectroscopy

    Ballet, O.

    1985-01-01

    Some useful relations are derived for the polarization dependent optical index of 57 Fe Moessbauer absorbers. Real rotation matrices are extensively used and, besides wave-direction dependence, their properties simplify also the treatment of texture and f-anisotropy. The derivation of absorber transmissivities from the optical index is discussed with a special emphasis on line overlapping. (Auth.)

  5. Moessbauer Studies in Chinese Archaeology: A Review

    Hsia Yuanfu; Huang Hongbo [Nanjing University, Department of Physics (China)

    2003-09-15

    The Moessbauer effect has been applied to a wide variety of objects related to Chinese archaeology. Besides ceramic artifacts, materials like porcelain, glazes, bronzes, ancient coins, ancient mineral drugs, and even fossils were studied. This article reviews these applications with particular emphasis on the study of the famous terracotta warriors and horses of the Qin Dynasty.

  6. An Object-Oriented Python Implementation of an Intermediate-Level Atmospheric Model

    Lin, J. W.

    2008-12-01

    The Neelin-Zeng Quasi-equilibrium Tropical Circulation Model (QTCM1) is a Fortran-based intermediate-level atmospheric model that includes simplified treatments of several physical processes, including a GCM-like convective scheme and a land-surface scheme with representations of different surface types, evaporation, and soil moisture. This model has been used in studies of the Madden-Julian oscillation, ENSO, and vegetation-atmosphere interaction effects on climate. Through the assumption of convective quasi-equilibrium in the troposphere, the QTCM1 is able to include full nonlinearity, resolve baroclinic disturbances, and generate a reasonable climatology, all at low computational cost. One year of simulation on a PC at 5.625 × 3.75 degree longitude-latitude resolution takes under three minutes of wall-clock time. The Python package qtcm implements the QTCM1 in a mixed-language environment that retains the speed of compiled Fortran while providing the benefits of Python's object-oriented framework and robust suite of utilities and datatypes. We describe key programming constructs used to create this modeling environment: the decomposition of model runs into Python objects, providing methods so visualization tools are attached to model runs, and the use of Python's mutable datatypes (lists and dictionaries) to implement the "run list" entity, which enables total runtime control of subroutine execution order and content. The result is an interactive modeling environment where the traditional sequence of "hypothesis → modeling → visualization and analysis" is opened up and made nonlinear and flexible. In this environment, science tasks such as parameter-space exploration and testing alternative parameterizations can be easily automated, without the need for multiple versions of the model code interacting with a bevy of makefiles and shell scripts. The environment also simplifies interfacing of the atmospheric model to other models (e.g., hydrologic models

  7. Current construction status of Korea Wolsong Nuclear Environment Management Center (low and intermediate level radioactive waste disposal facility)

    Suzuki, Yasuo

    2010-01-01

    Through the RANDEC delegation tour to Korea in Nov. 2009, we have earned new information on recent development of the radioactive waste management in Korea. In this report, we will introduce such development in Korea, focusing on the current construction status of Korean LILW (low and intermediate level radioactive waste) disposal site, now called, Wolsong Nuclear Environment Management Center. (author)

  8. A review of DOE chemical and geochemical research programmes (for disposal of low and intermediate level waste)

    May, R.

    1987-01-01

    A study of 26 DOE sponsored research programmes has been carried out with respect to their coverage of various chemical and geochemical issues posed by the proposed disposal of low and intermediate level wastes in a land repository. The study also took into account various experimental programmes sponsored by NIREX and abroad. The findings of the study are reported here. (author)

  9. Action taken by ENRESA and the NPPs with a view to reducing the production of low and intermediate level wastes

    Morales, A.; Rojo, F.

    1996-01-01

    In those countries in which the responsibilities of the different organizations involved in the management of low and intermediate level radioactive wastes (Regulatory Body, Agency, Facility Operators and Producers) are perfectly defined and a definitive Waste Disposal Facility is in operation, the next phase in order of importance consists of addressing a waste volume reduction policy aimed at optimizing storage capacity

  10. The influence of organic materials on the near field of an intermediate level waste radioactive waste repository

    Wilkins, J.D.

    1988-02-01

    The influence of organic materials, which are present in some intermediate level wastes, on the chemistry of the near field of a radioactive waste repository is discussed. Particular attention is given to the possible formation of water soluble complexing agents formed as a result of the radiation field and chemical conditions. The present state of the research is reviewed. (author)

  11. Leaf Potential Productivity at Different Canopy Levels in Densely-planted and Intermediately-thinned Apple Orchards

    Ying SUN

    2016-07-01

    Full Text Available Most apple orchards in the apple production districts in China were densely planted with vigorous rootstocks during the 1980s. These orchards have suffered micro-environmental deterioration and loss of fruit quality because of the closed canopy. Modification of the densely-planted orchards is a priority in current apple production. Intermediate thinning is a basic technique used to transform densely-planted apple orchards in China. Our goal was to provide theoretical basis for studying the effect of thinning on the efficiency of photosynthetically active radiation (PAR, fruit quality, and yield. We measured leaf area, solar radiation, and leaf air exchange at different tree canopy levels and by fitting relevant photosynthetic models, vertical distribution characteristics of leaf photosynthetic potentials and PAR were analyzed in various levels within canopies in densely-planted and intermediately-thinned orchards. Intermediate thinning significantly improved the radiant environment inside the canopies. PAR distribution within the canopies in the intermediately-thinned orchard was better distributed than in the densely-planted orchards. The invalid space under 30.0% of relative photosynthetically active radiation (PARr was nearly zero in the intermediately-thinned orchard; but minimum PARr was 17.0% and the space under 0.30 of the relative height of the canopy was invalid for photosynthesis in the densely-planted orchard. The leaf photosynthetic efficiency in the intermediately-thinned orchard was improved. Photosynthetic rates (Pn at the middle and bottom levels of the canopy, respectively, were increased by 7.80% and 10.20% in the intermediately-thinned orchard. Leaf development, which influences photosynthetic potential, was closely related to the surrounding micro-environment, especially light. Leaf photosynthetic potentials were correlated with leaf nitrogen content (Nl and specific leaf weight (Ml at various levels of canopies. Compared

  12. Holistic oil field value management: using system dynamics for 'intermediate level' and 'value-based' modelling in the oil industry

    Corben, D.; Stevenson, R.; Wolstenholme, E.F.

    1999-01-01

    System dynamics has been seen primarily as a strategic tool, most effectively used at the highest level of strategy to identify robust policy interventions under a wide range of scenarios. However, an alternative, complementary and powerful role is emerging. This is at an 'intermediate level' in organisations to coordinate and integrate policies across the value chain. It is at this level where business value, as defined by the discounted value of future free cash flow, is both created and destroyed. This paper introduces the need for 'intermediate-level' and 'value-based' modelling and emphasises the natural role of system dynamics in supporting a methodology to fulfil the need. It describes the development of an approach and its application in the oil industry to coordinate the response of people and tools within operational, financial and commercial functions across the value chain to address a variety of problems and issues. (author)

  13. The project for national disposal facility for low and intermediate level radioactive waste in Bulgaria

    Alexandrov, A.; Boyanov, S.; Christoskova, M.; Ivanov, A.

    2006-01-01

    The State Enterprise Radioactive Waste is the responsible organisation in Bulgaria for the radioactive waste management and, in particular, for the establishment of the national disposal facility (NDF) for low and intermediate level short-lived radioactive waste (LIL RAW SL). According to the national strategy for the safe management of spent fuel and radioactive waste the NDF should be commissioned in 2015. NDF will accept two main waste streams - for disposal and for storage if the waste is not disposable. The major part of disposable waste is generated by Kozloduy NPP. The disposal facility will be a near surface module type engineered facility. Consecutive erection of new modules will be available in order to increase the capacity of the facility. The corrective measures are previewed to be applied if needed - upgrading of engineered barriers and/or retrieval of the waste. The active control after the facility is closed should be not more than 300 years. The safety of the facility is supposed to be based on the passive measures based on defense in deep consisting of physical barriers and administrative measures. A multi barrier approach will be applied. Presently the NDF project is at the first stage of the facility life cycle - the site selection. The siting process itself consists of four stages - elaboration of a concept for waste disposal and site selection planning, data collection and region analyses, characterization of the preferred sites-candidates and site confirmation. Up till now the work on the first two stages of the siting process had been done by the SE RAW. Geological site investigations have been carried out for more than two decades all over the territory of the country. The results of the investigations have been summarized and analysed thoroughly. More than 40 potential sites have been considered, after the preselection 12 sites have been selected as favourable and among them 5 are pointed out as acceptable. The ultimate decision for a site

  14. Deep repository for long-lived low- and intermediate-level waste. Preliminary safety assessment

    1999-11-01

    A preliminary safety assessment has been performed of a deep repository for long-lived low- and intermediate-level waste, SFL 3-5. The purpose of the study is to investigate the capacity of the facility to act as a barrier to the release of radionuclides and toxic pollutants, and to shed light on the importance of the location of the repository site. A safety assessment (SR 97) of a deep repository for spent fuel has been carried out at the same time. In SR 97, three hypothetical repository sites have been selected for study. These sites exhibit fairly different conditions in terms of hydrogeology, hydrochemistry and ecosystems. To make use of information and data from the SR 97 study, we have assumed that SFL 3-5 is co-sited with the deep repository for spent fuel. A conceivable alternative is to site SFL 3-5 as a completely separate repository. The focus of the SFL 3-5 study is a quantitative analysis of the environmental impact for a reference scenario, while other scenarios are discussed and analyzed in more general terms. Migration in the repository's near- and far-field has been taken into account in the reference scenario. Environmental impact on the three sites has also been calculated. The calculations are based on an updated forecast of the waste to be disposed of in SFL 3-5. The forecast includes radionuclide content, toxic metals and other substances that have a bearing on a safety assessment. The safety assessment shows how important the site is for safety. Two factors stand out as being particularly important: the water flow at the depth in the rock where the repository is built, and the ecosystem in the areas on the ground surface where releases may take place in the future. Another conclusion is that radionuclides that are highly mobile and long-lived, such as 36 Cl and 93 Mo , are important to take into consideration. Their being long-lived means that barriers and the ecosystems must be regarded with a very long time horizon

  15. Derivation of Waste Acceptance Criteria for Low and Intermediate Level Waste in Surface Disposal Facility

    Gagner, L.; Voinis, S.

    2000-01-01

    In France, low- and intermediate-level radioactive wastes are disposed in a near-surface facility, at Centre de l'Aube disposal facility. This facility, which was commissioned in 1992, has a disposal capacity of one million cubic meters, and will be operated up to about 2050. It took over the job from Centre de la Manche, which was commissioned in 1969 and shut down in 1994, after having received about 520,000 cubic meters of wastes. The Centre de l'Aube disposal facility is designed to receive a many types of waste produced by nuclear power plants, reprocessing, decommissioning, as well as by the industry, hospitals and armed forces. The limitation of radioactive transfer to man and the limitation of personnel exposure in all situations considered plausible require limiting the total activity of the waste disposed in the facility as well as the activity of each package. The paper presents how ANDRA has derived the activity-related acceptance criteria, based on the safety analysis. In the French methodology, activity is considered as end-point for deriving the concentration limits per package, whereas it is the starting point for deriving the total activity limits. For the concentration limits (called here LMA) the approach consists of five steps: the determination of radionuclides important for safety with regards to operational and long-term safety, the use of relevant safety scenarios as a tool to derive quantitative limits, the setting of dose constraint per situation associated with scenarios, the setting of contribution factor per radionuclide, and the calculation of concentration activity limits. An exhaustive survey has been performed and has shown that the totality of waste packages which should be delivered by waste generators are acceptable in terms of activity limits in the Centre de l'Aube. Examples of concentration activity limits derived from this methodology are presented. Furthermore those limits have been accepted by the French regulatory body and

  16. Alternative systems of covering the low- and intermediate-level radioactive waste storage at Sallying

    Diaconu, Daniela

    2003-01-01

    The current concept of managing the low- and intermediate-level radioactive wastes produced during the operation of Cernavoda NPP provides their final disposal underground in the Sallying repository located within the NPP exclusion area. The safety requirements of the disposal imposed adopting of efficient natural and engineered systems to prevent population and environment exposure for at least 300 years time. Preliminary studies on the Sallying site showed that geological formations can prevent release radioisotopes in Eocene and Baramine aquifers both by their composition and structures. On the other hand investigation of the potential factors which could affect the long term stability of the repository showed that soil erosion due to climatic factors and soil degradation produced by animals burrowing underground drifts could rise the probability of environment contamination. These factors could enhance the escape of 14 C and 3 H radionuclides in the environment and a rise of water infiltration rate into the repository. A technical solution aiming at diminishing these effects specific to superficial or low-depth repositories appear to be a system of covering technical barriers as well as minimizing the effects of biointrusion. The paper analyses several geo textile membranes (polyesters and rubber) as well as soils compositions (loess, clay, sand, gravel) as technical a natural covering solutions. The studies and the experiments carried out led to the following four conclusions. 1. Without a multilayer covering system the saturation degree of the loess above the repository keeps low values varying between 20% and 25%. Although, the humidity increases considerably at the interface with the repository's concrete, so that within 0.5 m it reaches a saturation degree of 96%. The concrete block having a compact and fine structure directs laterally the water flow what entails a slight increase of humidity. 2. The capillary barriers keep the humidity in the upper part

  17. Assessment of the Biodegradability of Containers for Low and Intermediate Level Nuclear Waste

    Zlobenko, B.P.

    2013-01-01

    Concrete and reinforced concrete are widely used as engineered barriers (containers) for radioactive waste disposal facilities due to their isolating ability, mechanical stability and low cost. Several types of protective reinforced concrete containers for low and intermediate level waste have been designed in Ukraine. Evaluation of these containers for microbial stability is required according to NRC of Ukraine Regulation No.306.608-96. The research was therefore aimed at studying the degradation of the cement material due to microbiological interaction and the possibility of biodegraded cement as an ideal environment for the growth of other microorganisms under waste disposal conditions to satisfy the regulatory requirements. Results from this study indicated that Aspergillus niger induced gluconic and oxalic acids that dissolve portlandite (with a low leaching of calcium) after one year of contact time. This resulted in an increase in porosity, loss in tensile strength biomechanically deteriorated and cracking. XRD analysis identified crystalline precipitates within the biomass on the concrete surface as calcium oxalate dehydrate (weddellite) and calcium oxalate monohydrate (whewellite). The mechanism regarding of the microbiological interaction on the concrete surface can be summarized as follows: Phase 1: Fungi accumulate on the surface of the concrete, thereby degrading the concrete surface by biochemical and biomechanical interactions. When this effect is in the presence of air with available carbon dioxide, the micro fungi reduces the pH of the concrete from >13 to 8.5. During this phase no accumulation were observed in sections where granite aggregates are present. Phase 2: After reducing the pH of the concrete paste during phase 1, and provided that sufficient nutrients, moisture and oxygen are present sulphur oxidizing bacteria start to accumulate on the concrete surface. The result form this study therefore concluded that fungal biogeochemical activity

  18. Deep repository for long-lived low- and intermediate-level waste. Preliminary safety assessment

    NONE

    1999-11-01

    A preliminary safety assessment has been performed of a deep repository for long-lived low- and intermediate-level waste, SFL 3-5. The purpose of the study is to investigate the capacity of the facility to act as a barrier to the release of radionuclides and toxic pollutants, and to shed light on the importance of the location of the repository site. A safety assessment (SR 97) of a deep repository for spent fuel has been carried out at the same time. In SR 97, three hypothetical repository sites have been selected for study. These sites exhibit fairly different conditions in terms of hydrogeology, hydrochemistry and ecosystems. To make use of information and data from the SR 97 study, we have assumed that SFL 3-5 is co-sited with the deep repository for spent fuel. A conceivable alternative is to site SFL 3-5 as a completely separate repository. The focus of the SFL 3-5 study is a quantitative analysis of the environmental impact for a reference scenario, while other scenarios are discussed and analyzed in more general terms. Migration in the repository's near- and far-field has been taken into account in the reference scenario. Environmental impact on the three sites has also been calculated. The calculations are based on an updated forecast of the waste to be disposed of in SFL 3-5. The forecast includes radionuclide content, toxic metals and other substances that have a bearing on a safety assessment. The safety assessment shows how important the site is for safety. Two factors stand out as being particularly important: the water flow at the depth in the rock where the repository is built, and the ecosystem in the areas on the ground surface where releases may take place in the future. Another conclusion is that radionuclides that are highly mobile and long-lived, such as {sup 36}Cl and {sup 93}Mo , are important to take into consideration. Their being long-lived means that barriers and the ecosystems must be regarded with a very long time horizon.

  19. Theory of Moessbauer line broadening due to diffusion

    Schroeder, K.; Wolf, D.; Dederichs, P.H.

    1981-12-01

    We have calculated the line broadening of the Moessbauer line due to diffusion of Moessbauer atoms via single vacanices. We take into account the perturbation of vacancy jumps in the neighbourhood of an impurity Moessbauer atom (e.g. Fe in Al) using the 5-frequency model. The anisotropy of the line width is given by the Fourier transform of the final distribution of a Moessbauer atom after an encounter with a vacancy. This distribution is calculated by Monte Carlo computer simulation. 3 figures, 1 tables

  20. Moessbauer spectroscopic characterization of ferrite ceramics

    Music, S.; Ristic, M.

    1999-01-01

    The principle of Moessbauer effect and the nature of hyperfine interactions were presented. The discovery of the Moessbauer effect was the basis of a new spectroscopic technique, called Moessbauer spectroscopy, which has already made important contribution to research in physics, chemistry, metallurgy, mineralogy and biochemistry. In the present work the selected ferrites such as spinel ferrite, NiFe 2 O 4 , and some rare earth orthoferrites and garnets were investigated using Moessbauer spectroscopy. X-ray powder diffraction and Fourier transform infrared spectroscopy were used as complementary techniques. The formation of NiFe 2 O 4 was monitored during the thermal decomposition of mixed salt (Ni(NO 3 ) 2 +2Fe(NO 3 ) 3 )nH 2 O. The ferritization of Ni 2+ ions was observed at 500 deg. C and after heating at 1300 deg. C the stoichiometric NiFe 2 O 4 was produced. The Moessbauer parameters obtained for NiFe 2 O 4 , d Fe = 0.36 mm s -1 and HMF = 528 kOe, can be ascribed to Fe 3+ ions in the octahedral sublattice, while parameters d Fe = 0.28 mm s -1 and HMF = 494 kOe can be ascribed to Fe 3+ ions in the tetrahedral lattice. The effect of ball-milling of NiFe 2 O 4 was monitored. The formation of oxide phases and their properties in the systems Nd 2 O 3 -Fe 2 O 3 , Sm 2 O 3 -Fe 2 O 3 , Gd 2 O 3 -Fe 2 O 3 , Eu 2 O 3 -Fe 2 O 3 and Er 2 O 3 -Fe 2 O 3 were also investigated. Quantitative distributions of oxide phases, a-Fe 2 O 3 , R 2 O 3 , R 3 Fe 5 O 12 and RFeO 3 , R = Gd or Eu, were determined for the systems xGd 2 O 3 +(1-x)Fe 2 O 3 and xEu 2 O 3 +(1-x)Fe 2 O 3 . The samples, prepared by chemical coprecipitation in the system xEu 2 O 3 +(1-x)Fe 2 O 3 , 0≤x≤1, were completely amorphous as observed by XRD, even at the relatively high temperature of the sample preparation (600 deg. C). Similar behavior was observed during the formation of Er 3 Fe 5 O 12 . Moessbauer spectroscopy indicated that this 'amorphous' phase is actually composed of very small and/or poor

  1. Moessbauer spectroscopy of locally inhomogeneous systems

    Rusakov, V. S.; Kadyrzhanov, K. K.

    2004-01-01

    Substances with characteristic local inhomogeneities - with different from position to position neighborhood and properties of like atoms - gain recently increased scientific attention and wide practical application. We would call a system locally inhomogeneous if atoms in the system are in non-equivalent atomic locations and reveal different properties. Such systems are, first of all, variable composition phases, amorphous, multi-phase, admixture, defect and other systems. LIS are most convenient model objects for studies of structure, charge, and spin atomic states, interatomic interactions, relations between matter properties and its local characteristics as well as for studies of diffusion kinetics, phase formation, crystallization and atomic ordering; all that explains considerable scientific interest in such LIS. Such systems find their practical application due to wide spectrum of useful, and sometimes unique, properties that can be controlled varying character and degree of local inhomogeneity. Moessbauer spectroscopy is one of the most effective methods for investigation of LIS. Local character of obtained information combined with information on cooperative phenomena makes it possible to run investigations impossible for other methods. Moessbauer spectroscopy may provide with abundant information on peculiarities of macro- and microscopic state of matter including that for materials without regular structure. At the same time, analysis, processing and interpretation of Moessbauer spectra for LIS (that are sets of a large amount of partial spectra) face considerable difficulties. Development of computer technique is accompanied with development of mathematical methods used for obtaining physical information from experimental data. The methods make it possible to improve considerably, with some available a priori information, effectiveness of the research. Utilization of up-to-date mathematical methods in Moessbauer spectroscopy requires not only adaptation

  2. Geological factors of disposal site selection for low-and intermediate-level solid radwastes in China

    Chen Zhangru

    1993-01-01

    For disposal of low- and intermediate-level solid radioactive wastes, shallow-ground disposal can provide adequate isolation of waste from human for a fairly long period of time. The objective of disposal site selection is to ensure that the natural properties of the site together with the engineered barrier site shall provide adequate isolation of radionuclides from the human beings and environment, so the whole disposal system can keep the radiological impact within an acceptable level. Since the early 1980's, complying with the national standards and the expert's conception as well as the related IAEA Criteria, geological selection of disposal sites for low-and intermediate-level solid radwastes has been carried out in East China, South China, Northwest China and Southwest China separately. Finally, 5 candidate sites were recommended to the CNNC

  3. Moessbauer study of hemoglobin of diabetes

    Li Aiguo; Ni Xinbo; Cai Yingwen; Zhang Guilin; Zhang Hongde; Ge Yongxin

    2000-01-01

    The hemoglobins from normal adults (Gly-Hb 5%), people infected with diabetes (Gly-Hb 10%) and serious diabetics (Gly-Hb 15%) were investigated by Moessbauer spectroscopy at liquid nitrogen temperature. All the experimental spectra of hemoglobin are composed of three doublets corresponding to oxy-hemoglobin (Oxy-Hb), deoxy-hemoglobin (Deoxy-Hb) and low-spin hemo-chrome (Ls-Hemo) respectively. It is found that Oxy-Hb is decreasing but Deoxy-hb increasing for diabetes. Experimental results also indicate that the line-width of Moessbauer spectra of Oxy-Hb for diabetics is narrower than that for normal adults, showing that while Fe on Oxy-Hb exists in pile-up of some similar states for normal adults, but it becomes in single state for serious diabetes

  4. Moessbauer spectrometric data acquisition based on FPGA

    Zhang Yuan; Li Shimin; Chen Nan; Zhu Jingbo; Xia Yuanfu

    2008-01-01

    FPGA(Field Programmable Gate Array) is a programmable device with strong logical function and timing control ability. It is extremely potent in acquiring and processing timing signals. By replacing the traditional used SCM (Single-Chip Microcomputer) with FPGA, counting speed of Moessbauer spectrometric data acquisition can be improved markedly with significantly decreased size of the spectrometer. The counter, RAM and RS-232 communication of the module are developed on Altera Cyclone series chip EP1C6T144C8 with Quartus II. EP1C6T144C8 has 5980 logical units accompanied by 92160 bits of memory space. It is so powerful that all needs in data acquisition of the Moessbauer spectrometer can be perfectly satisfied while allowing modifications in functions and parameters. (authors)

  5. Fourier evaluation of broad Moessbauer spectra

    Vincze, I.

    1981-01-01

    It is shown by the Fourier analysis of broad Moessbauer spectra that the even part of the distribution of the dominant hyperfine interaction (hyperfine field or quadrupole splitting) can be obtained directly without using least-square fitting procedures. Also the odd part of this distribution correlated with other hyperfine parameters (e.g. isomer shift) can be directly determined. Examples for amorphous magnetic and paramagnetic iron-based alloys are presented. (author)

  6. Fourier evaluation of broad Moessbauer spectra

    Vincze, I.

    1981-09-01

    It is shown by the Fourier analysis of broad Moessbauer spectra that the even part of the distribution of the dominant hyperfine interaction (hyperfine field or quadrupole splitting) can be obtained directly without using least-square fitting procedures. Also the odd part of this distribution correlated with other hyperfine parameters (e.g. isomer shift) can be directly determined. Examples covering the case of amorphous magnetic and paramagnetic iron-based alloys are presented. (author)

  7. Fast-response personal Moessbauer spectrometer

    Kholmetskij, A.L.; Mashlan, M.; Misevich, O.V.; Evdokimov, V.A.; Lopatik, A.R.; Zhak, D.; Fedorov, A.A.; Snashel, V.

    1995-01-01

    Spectrometer design to record transmission Moessbauer spectra is described. The spectrometer consists of PC/AT computer with 1 mb memory and 40 mb hard disk, of EPSON LX 850 printer, of color monitor with VGA graphical adapter, of data accumulation system, of speed generator, of motion system with minivibrator, of scintillation detector with YA10 3 :Ce scintillator, of single-channel amplitude analyzer, of measuring bench and of 57 Co(Rh) source. 1 ref.; 1 fig

  8. Biological applications of the Moessbauer effect

    Boulay, P.

    1968-12-01

    The applications of Moessbauer spectrometry in the fields of physics and chemistry have been increasing steadily since its discovery in 1958. Attempts have been made to find applications in biology. Two possibilities of investigation exist in this field: the study of mechanical or vibrational movements in certain animal organs, and the determination of the organic molecular structure in a biological context. An example is given of each of these possibilities. (author) [fr

  9. Recent Developments in Synchrotron Moessbauer Reflectometry

    Deak, L.; Bottyan, L.; Major, M.; Nagy, D. L. [KFKI Research Institute for Particle and Nuclear Physics (Hungary); Spiering, H. [Johannes Gutenberg Universitaet, Mainz, Institute fuer Anorganische und Analytische Chemie (Germany); Szilagyi, E.; Tancziko, F. [KFKI Research Institute for Particle and Nuclear Physics (Hungary)

    2002-12-15

    Synchrotron Moessbauer Reflectometry (SMR), the grazing incidence nuclear resonant scattering of synchrotron radiation, can be applied to perform depth-selective phase analysis and to determine the isotopic and magnetic structure of thin films and multilayers. Principles and methodological aspects of SMR are briefly reviewed. Off-specular SMR provides information from the lateral structure of multilayers. In anti-ferromagneticly coupled systems the size of magnetic domains can be measured.

  10. Detectability in a derivative Moessbauer spectroscopy

    Yoshimura, Takeaki; Miyamoto, Masashi; Wakabayashi, Nobuo

    1978-01-01

    In Moessbauer spectrometry, a criterion for detecting a faint peak under the condition that the peak is superimposed onto a tail of a large and broad peak is discussed. By adopting a derivative method, it is found that the criterion is improved in comparison with a usual method, and that the condition for determining the modulation amplitude W/2 is 1.5 GAMMA 1 1 where GAMMA 1 is the spectral linewidth of the faint peak. (auth.)

  11. Application of Moessbauer spectroscopy to study corrosion

    Ramshesh, V.; Ravichandran, K.; Venkateswarlu, K.S.

    1976-01-01

    The system components in a nuclear power station include steel, stainless steel and various alloys such as Monel, Inconel, Stellite etc. Usually water/heavy water used as the coolant flows at high temperatures and pressures. Under such conditions the interaction of system components with the coolant produces a host of corrosion products. The deposition of such products is essential. This report attempts to review the salient features of identification of such corrosion products using Moessbauer spectroscopy. (author)

  12. Low and intermediate level waste repositories: Socioeconomic aspects and public involvement. Proceedings of a workshop

    2007-06-01

    Waste management facilities are needed to protect the environment and improve public health for the long term future. One significant challenge is to inform the public on the relative hazards of radioactive waste compared to other hazards in our modern society and to get the acceptance of the appropriate members of the public for these necessary facilities. Over the entire life cycle of these facilities, the projects must be managed without expending a disproportionate share of the collective resources. Public involvement plays a key role and the sophisticated and extensive public education systems that exist provide a vital service to gain public acceptance. There is a full range of compensation and benefit programmes used as incentives for hosting a LILW facility. Even if exemptions exist the experience in most countries indicate the direct/indirect incentives as a necessary part of gaining public acceptance. The countries, regions and local communities have their own established processes to make public decisions. Each organization developing a site must select and implement the methods that are acceptable within their framework of laws and regulations. A three day workshop on socio-economic issues and public involvement practices and approaches for developing and operating repositories for low and intermediate level waste took place in the IAEA headquarters on 9-11 November 2005. The workshop provided a forum where experts from Member States shared their experiences in non-technical aspects of planning, licensing and operating LILW disposal facilities. Description of both principles and practices applied in particular countries provides a useful overview of potential approaches in application of non-technical issues during a repository lifecycle. Participants presented approaches and practices applied in their countries, established new contacts and were able to take advantage of activities and experiences from abroad. There were 25 interesting presentations

  13. Geological evaluation of spent fuel storage and low-intermediate level radwaste disposal in the site of NPP candidate

    Sucipta; Yatim, S.; Martono, H.; Pudyo, A.

    1997-01-01

    Based on the consideration of techno-economy and environmental safety, the radioactive waste treatment installation (RWI), interim storage of spen fuel (ISSF) and low-intermediate level disposal shall be sited in the surrounding of NPP area. The land suitability of NPP's site candidate at Muria Peninsula as spent fuel storage and low-intermediate level radwaste disposal need to be studied. Site selection was conducted by overlay method and scoring method, and based on safety criteria which include geological and environmental aspects. Land evaluation by overlay method has given result a potential site which have highest suitable land at surrounding of borehole L-15 about 17.5 hectares. Land evaluation by scoring method has given result two land suitability classes, i.e. moderate suitability class (includes 14 borehole) and high suitability class, include borehole L-2, L-14 and L-15 (author)

  14. [Supporting the intermediate level of health care in urban health areas in Kinshasa (1995-2005), DR Congo].

    Mbeva, Jean-Bosco Kahindo; Schirvel, Carole; Karemere, Hermès; Porignon, Denis

    2012-06-08

    As a result of the decentralization of health systems, some countries have introduced intermediate (provincial) levels in their public health system. This paper presents the results of a case study conducted in Kinshasa on health system decentralization. The study identified a shift from a focus on regulation compliance assessment to an emphasis on health system coordination and health district support. It also highlighted the emergence of a?managerial (as opposed to a bureaucratic) approach to health district support. The performance of health districts in terms of health care coverage and health service use were also found to have improved. The results highlight the importance of intermediate levels in?the health care system and the value of a more organic and managerial rationality in supporting health districts faced with the complexity of urban environments and the integration of specialized multi-partner programs and interventions.

  15. Moessbauer spectroscopy as a tool in astrobiology

    Schroeder, Christian, E-mail: schroedc@uni-mainz.de; Klingelhoefer, Goestar, E-mail: klingel@mail.uni-mainz.de [Johannes Gutenberg-Universitaet, Institut fuer Anorganische Chemie und Analytische Chemie (Germany); Bailey, Brad E., E-mail: bebailey@ucsd.edu; Staudigel, Hubert, E-mail: hstaudigel@ucsd.edu [University of California San Diego, Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography (United States)

    2005-11-15

    Two miniaturized Moessbauer spectrometers are part of the Athena instrument package of the NASA Mars Exploration Rovers, Spirit and Opportunity. The primary objectives of their science investigation are to explore two sites on the surface of Mars where water may once have been present, and to assess past environmental conditions at those sites and their suitability for life. Aqueous minerals - jarosite at Meridiani Planum, Opportunity's landing site, and goethite in the Columbia Hills in Gusev Crater, Spirit's landing site - were identified by Moessbauer spectroscopy, thus providing in situ proof of water being present at those sites in the past. The formation of jarosite in particular puts strong constraints on environmental conditions during the time of formation and hence on the evaluation of potential habitability. On Earth Moessbauer spectroscopy was used to investigate microbially induced changes in Fe oxidation states and mineralogy at the Loihi deep sea mount, a hydrothermal vent system, which might serve as an analogue for potential habitats in the Martian subsurface and the sub-ice ocean of Jupiter's icy moon Europa.

  16. Moessbauer spectroscopy as a tool in astrobiology

    Schroeder, Christian; Klingelhoefer, Goestar; Bailey, Brad E.; Staudigel, Hubert

    2005-01-01

    Two miniaturized Moessbauer spectrometers are part of the Athena instrument package of the NASA Mars Exploration Rovers, Spirit and Opportunity. The primary objectives of their science investigation are to explore two sites on the surface of Mars where water may once have been present, and to assess past environmental conditions at those sites and their suitability for life. Aqueous minerals - jarosite at Meridiani Planum, Opportunity's landing site, and goethite in the Columbia Hills in Gusev Crater, Spirit's landing site - were identified by Moessbauer spectroscopy, thus providing in situ proof of water being present at those sites in the past. The formation of jarosite in particular puts strong constraints on environmental conditions during the time of formation and hence on the evaluation of potential habitability. On Earth Moessbauer spectroscopy was used to investigate microbially induced changes in Fe oxidation states and mineralogy at the Loihi deep sea mount, a hydrothermal vent system, which might serve as an analogue for potential habitats in the Martian subsurface and the sub-ice ocean of Jupiter's icy moon Europa.

  17. Moessbauer study of El-Bahrain meteorite

    Bahgat, A.A.; Ahmed, M.A.; Ramadan, T.M.

    2000-01-01

    A stone of brick-like shape, measuring roughly 25 x 12.5 x 10.5 cm 3 and weighing 14 kg was found in 1983, in the western desert of Egypt. The meteorite was named El-Bahrain meteorite and classified as L-chondrite. Principal constituents of El-Bahrain meteorite have been studied by means of Moessbauer spectroscopy. The chemical composition as obtained by the conventional wet analyses of L-chondritic meteorites showed that the meteorite contains 23,38% Fe and 1.23% Ni. While the analysis of the atomic absorption showed the presence of 27.03% as a total iron. The Moessbauer analysis of El-Bahrain meteorite showed that the iron constituent minerals were determined to be olivine, metallic iron-nickel alloys (kamacite, taenite and tetrataenite), ferrous sulfide (troilite) and weathering products such as maghemite and nanocrystalline hematite. The structure of meteoritic iron obtained by the Moessbauer analysis has been discussed on the basis of these constituents. (author)

  18. Moessbauer investigation of iron uptake in wheat

    Kovacs, K., E-mail: kkriszti@bolyai.elte.hu [Eoetvoes Lorand University, Laboratory of Nuclear Chemistry, Institute of Chemistry (Hungary); Kuzmann, E. [Hungarian Academy of Sciences, Laboratory of Nuclear Chemistry, Chemical Research Center (Hungary); Fodor, F.; Cseh, E. [Eoetvoes Lorand University, Department of Plant Physiology (Hungary); Homonnay, Z.; Vertes, A. [Eoetvoes Lorand University, Laboratory of Nuclear Chemistry, Institute of Chemistry (Hungary)

    2008-07-15

    Iron uptake and distribution in wheat roots were studied with {sup 57}Fe Moessbauer spectroscopy. Plants were grown both in iron sufficient and in iron deficient nutrient solutions. Moessbauer spectra of the frozen iron sufficient roots exhibited three iron(III) components with the typical average Moessbauer parameters of {delta} = 0.50 mm s{sup -1}, {Delta} = 0.43 mm s{sup -1}, {delta} = 0.50 mm s{sup -1}, {Delta} = 0.75 mm s{sup -1} and {delta} = 0.50 mm s{sup -1}, {Delta} = 1.20 mm s{sup -1} at 80 K. These doublets are very similar to those obtained earlier for cucumber [0], which allows us to suppose that iron is stored in a very similar way in different plants. No ferrous iron could be identified in any case, not even in the iron deficient roots, which confirms the mechanism proposed for iron uptake in the graminaceous plants.

  19. 40 Years of Experience of NIRAS / Belgoprocess on the Interim Storage of Low, Intermediate and High Level Waste

    Braeckeveldt, Marnix; Ghys, Bart

    2016-01-01

    Conclusion: • ONDRAF/NIRAS and Belgoprocess have gained over time an extended experience on the interim storage of Low-Intermediate and High level waste. • An systematic inspection strategy was developed in order the verify the conformity of the different waste-packages and corrective measures were taken to guarantee safe storage conditions. • From 2022 , ONDRAF/NIRAS will operate a surface disposal facility for LLW

  20. Summary report of a seminar on geosphere modelling requirements of deep disposal of low and intermediate level radioactive wastes

    Piper, D.; Paige, R.W.; Broyd, T.W.

    1989-02-01

    A seminar on the geosphere modelling requirements of deep disposal of low and intermediate level radioactive wastes was organised by WS Atkins Engineering Sciences as part of Her Majesty's Inspectorate of Pollution's Radioactive Waste Assessment Programme. The objectives of the seminar were to review geosphere modelling capabilities and prioritise, if possible, any requirements for model development. Summaries of the presentations and subsequent discussions are given in this report. (author)

  1. Comprehensive development plans for the low- and intermediate-level radioactive waste disposal facility in Korea and preliminary safety assessment

    Jung, Kang Il; Kim, Jin Hyeong; Kwon, Mi Jin; Jeong, Mi Seon; Hong, Sung Wook; Park, Jin Beak [Korea Radioactive Waste Agency, Daejeon (Korea, Republic of)

    2016-12-15

    The disposal facility in Gyeongju is planning to dispose of 800,000 packages of low- and intermediate- level radioactive waste. This facility will be developed as a complex disposal facility that has various types of disposal facilities and accompanying management. In this study, based on the comprehensive development plan of the disposal facility, a preliminary post-closure safety assessment is performed to predict the phase development of the total capacity for the 800,000 packages to be disposed of at the site. The results for each scenario meet the performance target of the disposal facility. The assessment revealed that there is a significant impact of the inventory of intermediate-level radionuclide waste on the safety evaluation. Due to this finding, we introduce a disposal limit value for intermediate-level radioactive waste. With stepwise development of safety case, this development plan will increase the safety of disposal facilities by reducing uncertainties within the future development of the underground silo disposal facilities.

  2. Moessbauer- and EPR-Snapshots of an Enzymatic Reaction: The Cytochrome P450 Reaction Cycle

    Schuenemann, V. [University of Luebeck, Institute of Physics (Germany); Jung, C. [Max-Delbrueck-Center for Molecular Medicine (Germany); Lendzian, F. [Technical University, PC 14, Max-Volmer Laboratory for Biophysical Chemistry (Germany); Barra, A.-L. [Grenoble High Magnetic Field Laboratory (France); Teschner, T.; Trautwein, A. X. [University of Luebeck, Institute of Physics (Germany)

    2004-12-15

    In this communication we present a complimentary Moessbauer- and EPR-study of the time dependance of the reaction of substrate free P450cam with peracetic acid within a time region ranging from 8 ms up to 5 min. An Fe(IV) species as well as a tyrosyl radical residing on the amino acid residue Tyr96 have been identified as reaction intermediates. These species possibly are formed by the reduction of compound I by means of transferring an electron from Tyr 96 to the heme moiety.

  3. Moessbauer- and EPR-Snapshots of an Enzymatic Reaction: The Cytochrome P450 Reaction Cycle

    Schuenemann, V.; Jung, C.; Lendzian, F.; Barra, A.-L.; Teschner, T.; Trautwein, A. X.

    2004-01-01

    In this communication we present a complimentary Moessbauer- and EPR-study of the time dependance of the reaction of substrate free P450cam with peracetic acid within a time region ranging from 8 ms up to 5 min. An Fe(IV) species as well as a tyrosyl radical residing on the amino acid residue Tyr96 have been identified as reaction intermediates. These species possibly are formed by the reduction of compound I by means of transferring an electron from Tyr 96 to the heme moiety.

  4. Studies on corrosion of mild steel by water using Moessbauer spectroscopy

    Nigam, A.N.; Tripathi, R.P.; Jangid, M.L.

    1987-01-01

    The corrosion of mild steel as a result of interaction with various types of local natural water samples and distilled water is studied with the help of Moessbauer spectroscopy. The data are supplemented with the studies on IR and magnetic properties as and when required. Distilled water and potable water behave in almost similar fashion wherein ferrihydrite and FeOOH are observed to be the precursors of magnetite, the end corrosion product. In case of brakish water, the additional species, viz., FeCl 2 , βFeOOH and an intermediate possibly FeOCl are accounted, and possible mechanisms are suggested. (author)

  5. Fuzzy multi-objective decision making on a low and intermediate level waste repository safety assessment

    Lemos, Francisco Luiz de; Deshpande, Ashok; Guimaraes, Lamartine

    2002-01-01

    Low and intermediate waste disposal facilities safety assessment is comprised of several steps from site selection , construction and operation to post-closure performance assessment. This is a multidisciplinary and complex task , and can not be analyzed by one expert only. This high complexity can lead to ambiguity and vagueness in information and consequently in the decision making process. In order to make the decision process clear and objective, there is the need to provide the decision makers with a clear and comprehensive picture of the whole process and, at the same time, simple and easily understandable by the public. This paper suggests the development of an inference system based on fuzzy decision making methodology. Fuzzy logic tools are specially suited to deal with ambiguous data by using language expressions. This process would be capable of integrating knowledge from various fields of environmental sciences. It has an advantage of keeping record of reasoning for each intermediate decision that lead to the final results which makes it more dependable and defensible as well. (author)

  6. Review of the microbiological, chemical and radiolytic degradation of organic material likely to be present in intermediate level and low level radioactive wastes

    Greenfield, B.F.; Rosevear, A.; Williams, S.J.

    1990-11-01

    A review has been made of the microbiological, chemical and radiolytic degradation of the solid organic materials likely to be present in intermediate-level and low-level radioactive wastes. Possible interactions between the three routes for degradation are also discussed. Attention is focussed on the generation of water-soluble degradation products which may form complexes with radioelements. The effects of complexation on radioelement solubility and sorption are considered. Recommendations are made for areas of further research. (author)

  7. Irradiation effects detected by Moessbauer spectroscopy in iron complexes

    Ladriere, J.

    1998-01-01

    The nature and the extent of the 60 Co gamma radiolysis of several iron coordination compounds have been analysed by Moessbauer absorption spectroscopy. The comparison of the radiolytic yields with the after effects observed by Moessbauer emission spectroscopy in similar 57 Co-doped compounds, supports the self-radiolysis model

  8. 57Fe Moessbauer spectroscopic studies on photosensitive nitrile hydratase (NHase)

    Kobayashi, Yoshio; Odaka, Masafumi

    2001-01-01

    57 Fe Moessbauer spectroscopy is a very useful technique for elucidating the chemical properties and biological changes of Fe species located at the reaction centers in various biological systems. We have applied 57 Fe Moessbauer spectroscopy to study the mechanism of photoactivation and the structural change caused by light irradiation of nitrile hydratase (NHase). (author)

  9. Moessbauer studies of superparamagnetic ferrite nanoparticles for functional application

    Mazeika, K., E-mail: kestas@ar.fi.lt; Jagminas, A.; Kurtinaitiene, M. [SSRI Center for Physical Sciences and Technology (Lithuania)

    2013-04-15

    Nanoparticles of CoFe{sub 2}O{sub 4} and MnFe{sub 2}O{sub 4} prepared for functional applications in nanomedicine were studied using Moessbauer spectrometry. Superparamagnetic properties of nanoparticles of different size and composition were compared applying collective excitations and multilevel models for the description of the Moessbauer spectra.

  10. Moessbauer study of Fe(III)-reducing sugar complexes

    Wolowiec, S.; Drabent, K.

    1985-01-01

    Iron(III) complexes with glucose, galactose, mannose and lactose were prepared. The Moessbauer and magnetic susceptibility data demonstrate the polymeric structure of the complexes. The thermal behaviour of the Fe(III)-glucose complex was monitored by Moessbauer spectroscopy. (author)

  11. Moessbauer study of magnetic properties of KFeF3

    Ito, A.; Morimoto, S.

    1975-01-01

    The results of the Moessbauer study of magnetic properties of KFeF 3 in a temperature range of 4.2 to 300 K are reported. Powdered and single crystal samples were used as absobers. Moessbauer spectra obtained for the powdered samples at various temperatures, for the single crystal with axial stress along the [111] direction obtained at 77 and 4.2 K and temperature dependences of the Moessbauer parameters are presented. The magnetic properties of KFeF 3 were found to be very sensitive to strain. The effect of strain was found to be significant near the Neel temperature and 40 K. Tsub(N) was determined by the Moessbauer study to be 112 K for the single-crystal-free and 117 K for the single-crystal-(111)-fixed sample. The Moessbauer spectra near Tsub(N) are given. (Z.S.)

  12. Moessbauer Effect applications using intense radioactive ion beams

    Taylor, R.D.

    1990-01-01

    The Moessbauer Effect is reviewed as a promising tool for a number of new solid state studies when used in combination with radioactive beam/implantation facilities. The usual Moessbauer Effect involves long-lived radioactive parents (days to years) that populate low-lying nuclear excited states that subsequently decay to the ground state. Resonant emission/absorption of recoil-free gamma rays from these states provide information on a number of properties of the host materials. Radioactive ion beams (RIB) produced on-line allow new Moessbauer nuclei to be studied where there is no suitable parent. The technique allows useful sources to be made having extremely low local concentrations. The ability to separate the beams in both Z and A should provide high specific activity ''conventional'' sources, a feature important in some applications such as Moessbauer studies in diamond anvil high pressure cells. Exotic chemistry is proposed using RIB and certain Krypton and Xenon Moessbauer isotopes

  13. A survey of possible microbiological effects within shallow land disposal sites designed to accept intermediate-level radioactive wastes

    Rushbrook, P.E.

    1985-01-01

    A literature survey was conducted to assess the current knowledge on microbial activity that may occur within a shallow intermediate-level waste disposal trench. Relatively little published information exists that is directly based on intermediate radioactive wasteforms, but relevant work was identified from other scientific fields. The likely environmental conditions within a disposal trench and their influence on microbial activity are considered. Also discussed are specific microbiological effects on waste packagings, backfill materials and concrete structures. Overall, it is unlikely that there will be extensive activity within the trenches and little evidence exists to suggest microbiologically-enhanced radionuclide migration,. The quantitative effect of microbial action is not possible to ascertain from the literature, but the general impression is that it will be low. Physical or chemical degradation processes are likely to predominate over those of a microbiological nature. Areas where further research would be valuable are also recommended. (author)

  14. Conditions for the test emplacement of intermediate-level radioactive wastes in chamber 8a of the 511 m level of the Asse Salt Mine

    1984-01-01

    The Gesellschaft fuer Strahlen- und Umweltforschung mbH (GSF) emplaces intermediate-level radioactive wastes which accumulate in an activity involving the use of radioactive materials that is licensed or reported in the Federal Republic of Germany or which are stored on an interim basis by the appropriate licensing or inspection agencies in chamber 8a of the 511 m level of the Asse Salt Mine in Remlingen near Wolfenbuettel in conjunction with an engineering test program. The type and form of the intermediate-level wastes must conform to certain conditions so that there are no hazards to personnel and the repository during transfer and subsequent storage. It is therefore necessary for the radioactive wastes to be treated and packaged before delivery in such a way that they satisfy the conditions presented in this document. The GSF shall inform the companies and organizations delivering wastes about its experiences with emplacement operations. The Conditions for the Test Emplacement of Intermediate-Level Radioactive Wastes in Chamber 8a of the 511 m Level of the Asse Salt Mine must be adapted to conform to the latest state of science and the art. The GSF must therefore reserve the right to modify the conditions, allowing for an appropriate transition period

  15. Interference effects in Moessbauer spectra of M1-transitions

    Peregudov, V.N.

    1980-01-01

    The purpose of the study is the calculation of interference effects in Moessbauer spectra of the (γ, e) reaction. Two channels of the inelastic (γ, e) reaction are considered: resonance gamma radiation absorption by nucleus accompanied by internal conversion and photo absorption by atomic electrons. The case of M1 nuclear transition multipolarity is considered. The expression for angular dependence coefficients of interference member is obtained. General expression for (γ, e) reaction cross section is obtained in a long-wave approximation for the case when the specimen is placed in longitudinal magnetic field involving superfine nuclear level splitting. The results of disperse amplitudes calculation for 93 Kr, 119 Sn, 129 I, 149 Sm, 151 Eu, 169 Tm, 183 W, 193 Ir, 197 Au nuclei are verified. The calculations show that maximum interference effect in the (γ, e) reaction should be expected for 169 Tm isotope [ru

  16. The Moessbauer spectroscopy in the characterization of atmospheric corrosion products

    Hernandez Torres, D.; Leiva Ronda, P.; Gomez, J.; Ronda, M.

    1996-01-01

    A study of corrosion products on mild steel formed after 1 and 5 years exposure in two industrial coastal weathering stations in the Bay from Matanzas City, Cuba, has been carried out. Structural analysis was conducted using mainly transmission Moessbauer Spectroscopy and the X-ray diffraction as complementary technique. The main phases found in the specimen exposed to high chloride containing environment were: lepidocrocite (γ- FeOOH), goethite (α- FeOOH) and magnetite concentration was the lowest, the phases found were γ- FeOOH and α- FeOOH, and the phase transformation proposed was γ- FeOOh -> α- Fe-OOH. In this station were found also amorphous corrosion products. There amorphous phases could be responsible for the lowest levels of corrosion on steel in this station

  17. Application of Moessbauer spectroscopy on corrosion products of NPP

    Dekan, J., E-mail: julius.dekan@stuba.sk; Lipka, J.; Slugen, V. [Institute of Nuclear and Physical Engineering, Faculty of Electrical Engineering and Information Technology, SUT (Slovakia)

    2013-04-15

    Steam generator (SG) is generally one of the most important components at all nuclear power plants (NPP) with close impact to safe and long-term operation. Material degradation and corrosion/erosion processes are serious risks for long-term reliable operation. Steam generators of four VVER-440 units at nuclear power plants V-1 and V-2 in Jaslovske Bohunice (Slovakia) were gradually changed by new original 'Bohunice' design in period 1994-1998, in order to improve corrosion resistance of SGs. Corrosion processes before and after these design and material changes in Bohunice secondary circuit were studied using Moessbauer spectroscopy during last 25 years. Innovations in the feed water pipeline design as well as material composition improvements were evaluated positively. Moessbauer spectroscopy studies of phase composition of corrosion products were performed on real specimens scrapped from water pipelines or in form of filters deposits. Newest results in our long-term corrosion study confirm good operational experiences and suitable chemical regimes (reduction environment) which results mostly in creation of magnetite (on the level 70 % or higher) and small portions of hematite, goethite or hydrooxides. Regular observation of corrosion/erosion processes is essential for keeping NPP operation on high safety level. The output from performed material analyses influences the optimisation of operating chemical regimes and it can be used in optimisation of regimes at decontamination and passivation of pipelines or secondary circuit components. It can be concluded that a longer passivation time leads more to magnetite fraction in the corrosion products composition.

  18. Altered dopamine levels induced by the parasite Profilicollis antarcticus on its intermediate host, the crab Hemigrapsus crenulatus

    JOSÉ MIGUEL ROJAS

    2005-01-01

    Full Text Available A serotonergic pathway is apparently involved in parasite-host interactions. Previous studies conducted in our laboratory showed increased rates in oxygen consumption and alterations in body posture in the crab Hemigrapsus crenulatus parasitized by the acanthocephalan, Profilicollis antarcticus. Such changes may be related to the functions described for biogenic amines in crustaceans. During the infective stage the acanthocephalans live freely in the hemocelomic cavity, suggesting that the possible alteration induced by biogenic amines may be related to their neurohormonal function in crustaceans. To test whether the presence of P. antarcticus produced neurohormonal changes in its intermediate host, H. crenulatus, we analyzed serotonin and dopamine levels in the host using HPLC with electrochemical detection. Two groups of 11 female crabs were studied; one group was artificially inoculated with two cystacanths while the other was used as the control. Our results show a dramatic increase in hemolymph dopamine, but not serotonin in H. crenulatus parasitized by the acanthocephalan P. antarcticus. Our results, along with those reported by Maynard (1996, suggest a parasite-specific strategy involved in the behavior alteration caused by the acanthocephalans on their intermediate host. The use of a biogenic amine as a mechanism of interaction by the parasites gives them an endless number of alternative potential actions on their intermediate hosts

  19. Altered dopamine levels induced by the parasite Profilicollis antarcticus on its intermediate host, the crab Hemigrapsus crenulatus.

    Rojas, José Miguel; Ojeda, F Patricio

    2005-01-01

    A serotonergic pathway is apparently involved in parasite-host interactions. Previous studies conducted in our laboratory showed increased rates in oxygen consumption and alterations in body posture in the crab Hemigrapsus crenulatus parasitized by the acanthocephalan, Profilicollis antarcticus. Such changes may be related to the functions described for biogenic amines in crustaceans. During the infective stage the acanthocephalans live freely in the hemocelomic cavity, suggesting that the possible alteration induced by biogenic amines may be related to their neurohormonal function in crustaceans. To test whether the presence of P. antarcticus produced neurohormonal changes in its intermediate host, H. crenulatus, we analyzed serotonin and dopamine levels in the host using HPLC with electrochemical detection. Two groups of 11 female crabs were studied; one group was artificially inoculated with two cystacanths while the other was used as the control. Our results show a dramatic increase in hemolymph dopamine, but not serotonin in H. crenulatus parasitized by the acanthocephalan P. antarcticus. Our results, along with those reported by Maynard (1996), suggest a parasite-specific strategy involved in the behavior alteration caused by the acanthocephalans on their intermediate host. The use of a biogenic amine as a mechanism of interaction by the parasites gives them an endless number of alternative potential actions on their intermediate hosts.

  20. Investigation of activity release from bituminized intermediate-level waste forms under thermal stresses

    Kluger, W.; Vejmelka, P.; Koester, R.

    1983-01-01

    To determine the consequences of a fire during fabrication, intermediate storage and transport of bituminized NaNO 3 waste forms, the fractions of plutonium released from the waste forms were assessed. For this purpose, laboratory tests were made with PuO 2 -containing specimens as well as a field test with specimens containing Eu 2 O 3 . By the evaluation of plutonium release in the laboratory and by the determination of the total sodium release and the relative Eu/Na release in the field tests the plutonium release can be deduced from full-scale specimens. The results show that for bituminized waste forms with high NaNO 3 contents (approx. 36 wt%) the average plutonium release obtained in laboratory testing is 15%. In the field tests (IAEA fire test conditions) an average Eu release of 8% was found. These results justify the statement that also for waste forms in open 175 L drum inserts a maximum plutonium release of about 15% can be expected. From the time-dependence of Eu/Na release in the field tests an induction period of 15-20 minutes between the start of testing and the first Na/Eu release can be derived. The maximum differential Na/Eu release occurs after a test period of 45 to 60 minutes duration and after 90 to 105 minutes (tests K2 and K4, respectively); after that time also the highest temperatures in the products are measured. The release values were determined for products in open 175 L drum inserts which in this form are not eligible for intermediate and ultimate storage. For bituminized waste forms in concrete packages (lost concrete shieldings) a delayed increase in temperature to only 70-80 deg. C takes place (4-5 hours after extinction of the fire) if the fire lasts 45 minutes. The concrete package remains intact under test conditions. This means that activity release from bituminized waste forms packaged in this way can be ruled out in the case under consideration. (author)

  1. Intermediate levels of hippocampal activity appear optimal for associative memory formation.

    Liu, X.; Qin, S.; Rijpkema, M.J.P.; Luo, J.; Fernandez, G.S.E.

    2010-01-01

    BACKGROUND: It is well established that hippocampal activity is positively related to effective associative memory formation. However, in biological systems often optimal levels of activity are contrasted by both sub- and supra-optimal levels. Sub-optimal levels of hippocampal activity are commonly

  2. Resolving the limitations of using glycine as EPR dosimeter in the intermediate level of gamma dose

    Aboelezz, E.; Hassan, G. M.

    2018-04-01

    The dosimetric properties of the simplest amino acid "glycine"- using EPR technique- were investigated in comparison to reference standard alanine dosimeter. The EPR spectrum of glycine at room temperature is complex, but immediately after irradiation, it appears as a triplet hyperfine structure probably due to the dominant contribution of the (•CH2COO-) radical. The dosimetric peak of glycine is at g-factor 2.0026 ± 0.0015 and its line width is 9 G at large modulation amplitude (7 G). The optimum microwave was studied and was found to be as alanine 8 mW; the post-irradiation as well as the dose rate effects were discussed. Dosimetric peak intensity of glycine fades rapidly to be about one quarter of its original value during 20 days for dried samples and it stabilizes after that. The dose response study in an intermediate range (2-1000 Gy) reveals that the glycine SNR is about 2 times more than that of alanine pellets when measured immediately after irradiation and 4 times more than that of glycine itself after 22 days of irradiation. The effect of energy dependence was studied and interpreted theoretically by calculation of mass energy absorption coefficient. The calculated combined uncertainties for glycine and alanine are nearly the same and were found to be 2.42% and 2.33%, respectively. Glycine shows interesting dosimetric properties in the range of ionizing radiation doses investigated.

  3. Intermediate and high energy nuclear reactions at the hadronic structural level

    Slowinski, B [Institute of Physics, Warsaw, University of Technology, Poland, Institute of Atomic Energy, Swierk, (Poland)

    1997-12-31

    Form tens of MeV to several hundred of GeV is stretched out quite a large interval of energy when the interaction between hadrons (for instance, pion/nucleon-nucleus and nucleus-nucleus reactions) can be described by the considerably simplified way with still acceptable accuracy. This happens because in this energy region hadrons (i.e. pions, nucleons etc.) remain quasiparticles of nuclear matter mostly without revealing any internal structure, their de Broglie`s wavelength is much shorter as compared to the average intranuclear nucleon`s distance, and the energy transfers in the reaction are, on the average, significantly greater than the binding energy of nucleons inside nuclei. Consequently an approach to the analysis of these phenomena based on simple geometric and probabilistic considerations is justifiable, especially for many practical purposes, in particular, for shielding and dosimetric estimations, material behaviour prediction, as well as for the approximate evaluation of electronuclear breeding effects in different composites of target materials, for nuclear passivation problems and so on. In this work basic physical reasons of such a simplified picture of intermediate and high energy nuclear reactions are presented. The most usual phenomenological models of hadronic multiple emission/production and recent results of the cascade evaporation type models, are also discussed. 2 figs.

  4. Special Analysis for Disposal of High-Concentration I-129 Waste in the Intermediate-Level Vaults at the E-Area Low-Level Waste Facility

    Collard, L.B.

    2000-01-01

    This revision was prepared to address comments from DOE-SR that arose following publication of revision 0. This Special Analysis (SA) addresses disposal of wastes with high concentrations of I-129 in the Intermediate-Level (IL) Vaults at the operating, low-level radioactive waste disposal facility (the E-Area Low-Level Waste Facility or LLWF) on the Savannah River Site (SRS). This SA provides limits for disposal in the IL Vaults of high-concentration I-129 wastes, including activated carbon beds from the Effluent Treatment Facility (ETF), based on their measured, waste-specific Kds

  5. Special Analysis for Disposal of High-Concentration I-129 Waste in the Intermediate-Level Vaults at the E-Area Low-Level Waste Facility

    Collard, L.B.

    2000-09-26

    This revision was prepared to address comments from DOE-SR that arose following publication of revision 0. This Special Analysis (SA) addresses disposal of wastes with high concentrations of I-129 in the Intermediate-Level (IL) Vaults at the operating, low-level radioactive waste disposal facility (the E-Area Low-Level Waste Facility or LLWF) on the Savannah River Site (SRS). This SA provides limits for disposal in the IL Vaults of high-concentration I-129 wastes, including activated carbon beds from the Effluent Treatment Facility (ETF), based on their measured, waste-specific Kds.

  6. Moessbauer study of iron diffusion in beryllium

    Sepiol, B.; Ruebenbauer, K.; Miczko, B.; Birchall, T.

    1991-01-01

    The broadening of the 14.41 keV Moessbauer line of 57 Fe dure to diffusion of iron atoms in polycrystalline beryllium has been investigated in the temperature range 1123 to 1423 K. The observed broadenings obey the Arrhenius law with activation energy 1.66(10) eV, i.e., lower than that obtained from the corresponding polycrystalline tracer data. The variations of the resonant fraction, second order Doppler shift and quadrupole splitting versus temperature are reported. An average diffusion coefficient has been calculated from the obtained broadenings and compared with the tracer results. (orig.)

  7. Optimal configuration for programmable Moessbauer experiments

    Pasquevich, Gustavo A; Veiga, Alejandro L; Zelis, Pedro Mendoza; Sanchez, Francisco H, E-mail: gpasquev@fisica.unlp.edu.a [Departamento de Fisica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (Argentina)

    2010-03-01

    Based on channel independency of recently developed Moessbauer instrumentation an approximation to optimal configuration of experiments is presented. The analysis relies on the presumption that all the available channels of the spectrum are not equally efficient for a given experimental application. A quantification of this concept is presented and a method for different channel layout comparison is proposed. The optimization of recorded spectra is important in dynamic experiments where efficiency in data taking imposes feasibility limits as well as in static applications as a way of reducing experimental time.

  8. Study Moessbauer of chromites of South Africa

    Lopez, Ada; Velazquez, R.

    1997-01-01

    Coming natural chromites from South Africa they were studied by spectroscopy Moessbauer and X-rays diffraction. The ionic distribution of the ions of iron is reported in the area tetrahedral and octahedral in the structure showing that the pattern an orderly distribution, the chromites nearby to an inverse spinel. The microanalysis shows a certain variability in the composition in the coming specimen of the same area and could be the cause the apparent evolution of the chromite in the laterization process. We try to compare these results with a similar study coming f rom basaltic rocks of the Nemby Hill in oriental region of Paraguay [es

  9. Iron oxides characterization by Moessbauer spectroscopy

    Basurto Sanchez, R.

    1993-01-01

    In this work rust development on low carbon wire surface after the conformation process at different temperatures was studied by Moessbauer spectroscopy. The characterization was made by determining the following spectral parameters; 1) Quadrupole splitting, 2) Isomer shift, and 3) Magnetic splitting. The area quantification determined the percentage amount of three different iron oxides. These iron oxides were: a) Wustite (Fe O), b) Hematite (Fe 2 O 3 ), and c) Magnetite (Fe 3 O 4 ) which were present in the rust studied. With the results it was possible to establish the best temperature to favor the development of each of these iron oxides. (Author)

  10. Implementation of the Electron conversion Moessbauer spectroscopy

    Hernandez, Torres, D.; Noriega Scull, C.

    1996-01-01

    In the present work has been exposed the principles of the Conversion Moessbauer Electron Spectroscopy and its possibilities of application. Is also described the operation of the parallel plate avalanche detector made at the CEADEN starting from modifications done to the Gancedo's model and is exposed examples of the use of this detector in the characterization of corroded surfaces, with chemical cleaning and in samples of welded joints. The experiences obtained of this work were extended to the National Polytechnic Institute of Mexico where a similar detector, made in our center, was installed there

  11. Backscattering Moessbauer spectroscopy of Martian dust

    Bertelsen, P.; Madsen, M. B.; Binau, C. S.; Goetz, W.; Gunnlaugsson, H. P.; Hviid, S. F.; Kinch, K. M.; Klingelhoefer, G.; Leer, K.; Madsen, D. E.; Merrison, J.; Olsen, M.; Squyres, S. W.

    2005-01-01

    We report on the determination of the mineralogy of the atmospherically suspended Martian dust particles using backscattering 57 Fe Moessbauer spectroscopy on dust accumulated onto the magnets onboard the Mars Exploration Rovers. The spectra can be interpreted in terms of minerals of igneous origin, and shows only limited, if any, amounts of secondary minerals that may have formed in the presence of liquid water. These findings suggest that the dust has formed in a dry environment over long time in the history of the planet.

  12. Prediction of radionuclide inventory for the low-and intermediated-level radioactive waste disposal facility the radioactive waste classification

    Jung, Kang Il; Jeong, Noh Gyeom; Moon, Young Pyo; Jeong, Mi Seon; Park, Jin Beak

    2016-01-01

    To meet nuclear regulatory requirements, more than 95% individual radionuclides in the low- and intermediate-level radioactive waste inventory have to be identified. In this study, the radionuclide inventory has been estimated by taking the long-term radioactive waste generation, the development plan of disposal facility, and the new radioactive waste classification into account. The state of radioactive waste cumulated from 2014 was analyzed for various radioactive sources and future prospects for predicting the long-term radioactive waste generation. The predicted radionuclide inventory results are expected to contribute to secure the development of waste disposal facility and to deploy the safety case for its long-term safety assessment

  13. Performance of backfill materials in near surface disposal facilities for low and intermediate level radwaste. Appendix 4: China (a)

    Cunli, G.; Yawen, H.; Zhiwen, F.; Anxi, C.; Xiuzhen, L.; Jinsheng, Z.

    2001-01-01

    Full text: Backfill material is an important component of a multi-barriered disposal facility for low and intermediate level radioactive waste. This appendix describes the work concerning 'performance study on engineering materials of shallow land disposal of low and intermediate level radwaste'. At the time of the CRP, China had planned to establish five regional disposal sites for low-and-intermediate level radioactive waste. According to the potential distribution of these sites, forty-three sampling points were selected through information survey and table discussion. After field survey and screening, eight of them were selected for further studies in laboratory. Basic physical and chemical properties of each sample were measured in laboratory. The results indicate that no one of the samples can individually function as the backfill material in a multi-barriered near surface facility. Then nine additives for adsorption modification were tested using a static method. Further adsorption tests were conducted: three additives screened out in previous experiment were evaluated using the static method. Results obtained show that the Kd values of mixtures of 90% NW-3 and 10% BC for Co-60, Cs-134 and Sr-85, compared with those of 100% NW-3, are 4.8, 4.6 and 4.7 times higher, respectively. Effects of contact time, pH of tracer solutions and radionuclide concentrations of tracer solutions on Kd values of three samples, NW-3, BC and 90% NW-3 with 10% BC, were also be evaluated using the static method. Column tests were performed to evaluate migration of Co-60, Cs-134 and Sr-85 in NW-3 columns with different densities. The column tests were carried out for 210 days. However, no breakthrough was obtained. Long term performance of backfill materials was assessed through natural analogue. We compared Chinese ancient tombs with near-surface low and intermediate level radioactive waste (LILW) disposal facilities. Both were designed based upon multi-barrier principle. Then three

  14. Radioactive Operations Committee Review of the Intermediate-Level Waste Evaporator Facility, Building 2531 February 17, 1972

    Liberman, B.; Brooksbank, R.E.

    1972-01-01

    A subcommittee of the Radioactive Operations Committee met with the Operators of the Intermediate Level Waste Evaporator Facility on February 17, 1972, to discuss the status of the facility and its operations since the review of October 7, 1970, and reported in ORNL-CF-70-11-12. This review was made to determine the status of the ILWEF since the last review, to discuss compliance with previously recommended changes, and to review any new items of safety significance. Several recommendations were made.

  15. Characterization of decontamination factors for evaporators used in the treatment of low and intermediate level liquid radioactive wastes

    Rood, L.B.; Law, C.G. Jr.

    1972-01-01

    Evaporator decontamination factors were studied as functions of boiloff rate, volume reduction, and feed pH. A bench-scale vertical tube evaporator operating on simulated intermediate level nuclear wastes was used. Decontamination factors were not found to be strong functions of volume reduction or boiloff below vapor velocities of 25 lb/ft 2 -hr. At higher vapor fluxes, splashing was encountered. Foaming occurred at a feed pH of 6 but not at higher values. The presence of radioisotopes in the feed had no effect on evaporator performance

  16. Resource Conservation and Recovery Act closure plan for the Intermediate-Level Transuranic Storage Facility mixed waste container storage units

    Nolte, E.P.; Spry, M.J.; Stanisich, S.N.

    1992-11-01

    This document describes the proposed plan for clean closure of the Intermediate-Level Transuranic Storage Facility mixed waste container storage units at the Idaho National Engineering Laboratory in accordance with the Resource Conservation and Recovery Act closure requirements. Descriptions of the location, size, capacity, history, and current status of the units are included. The units will be closed by removing waste containers in storage, and decontamination structures and equipment that may have contacted waste. Sufficient sampling and documentation of all activities will be performed to demonstrate clean closure. A tentative schedule is provided in the form of a milestone chart

  17. A comparative study using liquid scintillation counting to determine 63Ni in low and intermediate level radioactive waste

    Gautier, Celine; Colin, Christele; Garcia, Cecile

    2016-01-01

    A comparative study using liquid scintillation counting was performed to measure 63 Ni in low and intermediate level radioactive waste. Three dimethylglyoxime (DMG)-based radiochemical procedures (solvent extraction, precipitation, extraction chromatography) were investigated, the solvent extraction method being considered as the reference method. Theoretical speciation calculations enabled to better understand the chemical reactions involved in the three protocols and to optimize them. In comparison to the method based on DMG precipitation, the method based on extraction chromatography allowed to achieve the best results in one single step in term of recovery yield and accuracy for various samples. (author)

  18. Reconnaissance survey of the intermediate-level liquid waste transfer line between X-10 and the hydrofracture site

    Duguid, J.O.; Sealand, O.M.

    1975-08-01

    Two leakage points on an intermediate-level liquid waste line were located. The waste line is used periodically to transfer waste between X-10 and the hydrofracture site. The first leak occurred prior to this survey and had been repaired, but no contaminated soil had been removed. The second leak resulted in soil contamination that was more intense than at the first leak. Analyses of soil samples taken from both locations are given in this report. Groundwater data indicate the effectiveness of the removal of the contaminated material from leak two. 1 ref., 5 figs., 3 tabs

  19. Reconnaissance survey of the intermediate level liquid waste transfer line between X-10 and the hydrofracture site

    Duguid, J.O.; Sealand, O.M.

    1975-08-01

    Two leakage points on an intermediate-level liquid waste line were located. The waste line is used periodically to transfer waste between X-10 and the hydrofracture site. The first leak had occurred prior to this survey and had been repaired. However, no contaminated soil had been removed. The second leak had not been discovered previously and soil contamination in this area was more intense than at the first leak. Analyses of soil samples taken from both locations are given in this report. Groundwater data that indicate the effectiveness of the removal of the contaminated material from leak two are presented. (U.S.)

  20. Intermediate, low, and very low level waste management at ANDRA (agence nationale pour la gestion des dechets radioactifs) in France

    Senoo, Muneaki

    2005-01-01

    On 28th September in 2004, RANDEC invited Mr. Jean-Louis Tison from ANDRA as a lecturer of the special session of the 16th RANDEC Annual Symposium. An ANDRA-RANDEC technical meeting was held on the next day, where Mr. Vincent Carlier invited from ANDRA, too participated. Here, present status of intermediate, low, and very low level waste management in France is reviewed based on the information which were obtained from the special session of the 16th RANDEC Annual Symposium and the ANDRA-RANDEC technical meeting. In France, ANDRA is implementing radioactive waste management under the following policy; 'Intermediate, low, and very-low-level (ILVLL) waste is managed in order to establish as soon as possible a final disposal system, the temporary or long term storage option being considered only for the high-level waste (HLW) such as the vitrified fission products or particular materials such as some sealed sources for which no final disposal solution still exists.' The Agency is financed on the basis of the 'polluter-pays' principle and contracts its services directly with waste owners. (author)

  1. Current issues in the management of low- and intermediate-level radioactive wastes from Ontario Hydro's CANDU reactors

    Krasznai, J.P.; Vaughan, B.R.; Williamson, A.S.

    1990-01-01

    Nuclear generating stations (NGSs) in Canada are operated by utilities in Ontario, Quebec, and New Brunswick. Ontario Hydro, with a committed nuclear program of 13,600 MW(electric) is the major producer of CANDU pressurized heavy-water reactor (PHWR) low- and intermediate-level radioactive wastes. All radioactive wastes with the exception of irradiated fuel are processed and retrievably stored at a centralized facility at the Bruce Nuclear Power Development site. Solid-waste classifications and annual production levels are given. Solid-waste management practices at the site as well as the physical, chemical, and radiochemical characteristics of the wastes are well documented. The paper summarizes types, current inventory, and estimated annual production rate of liquid waste. Operation of the tritium recovery facility at Darlington NGS, which removes tritium from heavy water and produces tritium gas in the process, gives rise to secondary streams of tritiated solid and liquid wastes, which will receive special treatment and packaging. In addition to the treatment of radioactive liquid wastes, there are a number of other important issues in low- and intermediate-level radioactive waste management that Ontario Hydro will be addressing over the next few years. The most pressing of these is the reduction of radioactive wastes through in-station material control, employee awareness, and improved waste characterization and segregation programs. Since Ontario Hydro intends to store retrievable wastes for > 50 yr, it is necessary to determine the behavior of wastes under long-term storage conditions

  2. The chemical, microbial, sensory and technological effects of intermediate salt levels as a sodium reduction strategy in fresh pork sausages.

    Cluff, MacDonald; Steyn, Hannes; Charimba, George; Bothma, Carina; Hugo, Celia J; Hugo, Arno

    2016-09-01

    The reduction of sodium in processed meat products is synonymous with the use of salt replacers. Rarely has there been an assessment of the use of intermediate salt levels as a sodium reduction strategy in itself. In this study, 1 and 1.5% salt levels were compared with 0 and 2% controls in fresh pork sausages for effects on chemical, microbial, sensory and technological stability. Although significant (P sausages stored at 4 °C on days 6 and 9 and stored at -18 °C on days 90 and 180; taste, texture and overall liking during sensory evaluation; and % cooking loss, % total loss and % refrigeration loss. Consumers were able to differentiate between the 2 and 1% added NaCl treatments in terms of saltiness. This study indicated that salt reduction to intermediate levels can be considered a sodium reduction strategy in itself but that further research with regards to product safety is needed. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  3. Moessbauer spectroscopy of metals from birth to death

    Fujita, Francisco Eiichi

    1998-01-01

    In today's metallurgy, precision techniques, such as X-ray and electron diffraction, electron microscopy, infrared spectroscopy and electron probe micro-analyzer, are being indispensably used, and, comparing to them, Moessbauer spectroscopy is not inferior at all in usefulness, convenience and cost benefit. Actually, however, it is not yet popular among the metallurgists probably because people believe that the Moessbauer effect is a difficult physics, radioactive sources are difficult to handle, and spectral analyses are complicated. These beliefs are in fact groundless and must be dissolved for further diffusion of this useful Moessbauer technique in metals and other industries.The present introductory talk intends to help people's better understanding and no anxiety for using the Moessbauer spectroscopy by showing how it can be applied to various problems of metals and alloys from their birth to the end, that is, from the study of minerals and ores before smelting to that of corrosion and other failures.Firstly, the principle of Moessbauer spectroscopy will be explained with simplest illustrations together with simple pictures of apparatuses including the high temperature furnace and the high pressure cell.In the second will be shown typical examples of Moessbauer patterns of magnetite, carbon steel and other alloys, with indications of how to analyze the seemingly complicated spectra. Some other examples will be shown with special apparatuses easy to measure. The usefulness and convenience of Moessbauer spectroscopy will be understood again from these examples. More examples will be on amorphous alloys and other advanced materials

  4. Measurement methodology for fulfilling of waste acceptance criteria for low and intermediate level radioactive waste in storages - 59016

    Sokcic-Kostic, M.; Langer, F.; Schultheis, R.

    2012-01-01

    Low and intermediate level radioactive waste must be sorted and treated before it can be sent to radioactive waste storage. The waste must fulfil an extensive amount of acceptance criteria (WAC) to guarantee a safe storage period. NUKEM Technologies has a broad experience with the building and management of radioactive waste treatment facilities and has developed methods and equipment to produce the waste packages and to gather all the required information. In this article we consider low and intermediate level radioactive waste excluding nuclear fuel material, even fresh fuel with low radiation. Only solid radioactive waste (RAW) will be considered. (Liquid RAW is usually processed and solidified before storage. Exception is the reprocessing of nuclear fuel.) Low and intermediate level radioactive waste has to be kept in storage facilities until isotopes are decayed sufficiently and the waste can be released. The storage has to fulfil certain conditions regarding the possible radiological impact and the possible chemical impact on the environment. With the inventory of nuclear waste characterised, the radiological impact can be estimated. RAW mainly originates from the operation of nuclear power plants. A small amount comes from reprocessing installations or from research entities. Chemical safety aspects are of qualitative nature, excluding substances in whole but not compared to limit values. Therefore they have minor influence on the storage conditions. Hereby corrosion and immobilisation of the waste play important roles. The storage concept assumes that the waste will be released if the radioactivity has decreased to an acceptable level. NUKEM Technologies has been specialised on collecting all data needed for the fulfilling of waste acceptance criteria (WAC). The classification as low or intermediate level waste is made on base of surface dose rate of the waste package as well as on the mass specific beta activity. Low level waste must not include isotopes

  5. A preliminary assessment of the assignment of Intermediate Level Waste streams to designs of transport containers

    Mairs, J.H.

    1984-08-01

    This paper considers the assignment of ILW to designs of transport container. Estimates are made of the radiation levels penetrating the transport containers and assesses the duration of any storage required prior to transportation. (author)

  6. Moessbauer and NMR study of novel Tin(IV)-lactames

    Kuzmann, Erno; Szalay, Roland; Homonnay, Zoltan, E-mail: homonnay@ludens.elte.hu; Nagy, Sandor [Eoetvoes Lorand University, Institute of Chemistry (Hungary)

    2012-03-15

    N-tributylstannylated 2-pyrrolidinone was reacted with tributyltin triflate in different molar ratios and the complex formation monitored using {sup 1}H-NMR, {sup 13}C-NMR and {sup 119}Sn Moessbauer spectroscopy. Comparing the carbon NMR and tin Moessbauer results, a reaction scheme is suggested for the complexation which assumes the formation of a simultaneously O- and N-tributylstannylated pyrrolidinone cation. The formation of the only O-stannylated pyrrolidinone is also assumed to account for the non-constant Moessbauer parameters of the two tin environments in the distannylated pyrrolidinone cation when the ratio of tributyltin triflate is increased in the reaction.

  7. Moessbauer sum rules for use with synchrotron sources

    Lipkin, Harry J.

    1999-01-01

    The availability of tunable synchrotron radiation sources with millivolt resolution has opened new prospects for exploring dynamics of complex systems with Moessbauer spectroscopy. Early Moessbauer treatments and moment sum rules are extended to treat inelastic excitations measured in synchrotron experiments, with emphasis on the unique new conditions absent in neutron scattering and arising in resonance scattering: prompt absorption, delayed emission, recoil-free transitions and coherent forward scattering. The first moment sum rule normalizes the inelastic spectrum. New sum rules obtained for higher moments include the third moment proportional to the second derivative of the potential acting on the Moessbauer nucleus and independent of temperature in the the harmonic approximation

  8. Multiwire proportional chamber for Moessbauer spectroscopy: development and results

    Costa, M.S. da.

    1985-12-01

    A new Multiwere proportional Chamber designed for Moessbauer Spectroscopy is presented. This detector allows transmission backscattering experiments using either photons or electrons. The Moessbauer data acquisition system, partially developed for this work is described. A simple method for determining the frontier between true proportional and semi-proportional regions of operation in gaseous detectors is proposed. The study of the tertiary gas mixture He-Ar-CH 4 leads to a straight forward way of energy calibration of the electron spectra. Moessbauer spectra using Fe-57 source are presented. In particular those obtained with backsattered electrons show the feasibility of depth selective analysis with gaseous proportional counters. (author) [pt

  9. Adapting the notion of natural (geological) barrier for final disposal of low- and intermediate-level radioactive wastes in Romania

    Durdun, I.; Marunteanu, C.; Andrei, V.

    2001-01-01

    According to the Minimum Disturbances Design (MDD) notion by Carl-Olof Morfeldt of Mineconsult, Sweden, any site selection, design and construction of low- and intermediate-level radioactive waste repository should be based on a thorough knowledge of the geological environmental so that the implantation of the disposal facility induce no significant harmful consequences. This work presents the way in which the Romanian program of radioactive waste management was implemented for disposal of low- and intermediate-level radioactive wastes from Cernavoda NPP. Based on geological criteria of selection of lithologic, petrographic, tectonic, seismologic, hydrologic and geo-technic nature, 37 sites were analyzed from which 2 were retained and finally one, Saligny site, was chosen, as the most close to Cernavoda NPP. Also, public acceptance and transport connections were taken into consideration. SUTRA, SWMS-2D and CHAIN-2D codes were applied to analyze the safety and the geological barrier effects. The barrier consists in red clay, a smectitic mineralogic compound. The computation showed that in Saligny vault the maximal tritium extension is kept inside due to the red clay barrier. Geo-technical engineering works were conducted to improve the properties of the loess upper layer which resulted in lowering its sensitivity to moistening and erosion

  10. Project Guarantee 1985. Final repository for low- and intermediate-level radioactive wastes: The system of safety barriers

    Anon.

    1985-01-01

    The safety barrier system for the type B repository for low- and intermediate-level waste is described. The barrier parameters which are relevant for safety analysis are quantified and associated error limits and data scatter are given. The aim of the report is to give a summary documentation of the safety analysis input data and their scientific background. For secure containment of radioactive waste safety barriers are used which effectively limit the release of radioactive material from the repository (release barriers) and effectively retard the entry of the original radioactive material into the biosphere (time barriers). In the case of low- and intermediate-level waste the technical safety barrier system comprises: waste solidification matrix (cement, bitumen and resin), immobilisation of the waste packages in containers using liquid cement, concrete repository containers, backfilling of remaining vacant storage space with special concrete, concrete lining of the repository caverns, sealing of access tunnels on final closure of the repository. Natural geological safety barriers - host rock and overlying formations - have the following important functions. Because of its stability, the host rock in the repository zone protects the technical safety barrier system from destruction caused by climatic effects and erosion for a sufficient length of time. It also provides for low water flow and favourable chemistry (reducing conditions)

  11. Advances in constant-velocity Moessbauer instrumentation

    Veiga, A.; Martinez, N.; Zelis, P. Mendoza; Pasquevich, G. A.; Sanchez, F. H.

    2006-01-01

    A prototype of a programmable constant-velocity scaler is presented. This instrument allows the acquisition of partial Moessbauer spectra in selected energy regions using standard drivers and transducers. It can be fully operated by a remote application, thus data acquisition can be automated. The instrument consists of a programmable counter and a constant-velocity reference. The reference waveform generator is amplitude modulated with 13-bit resolution, and is programmable in a wide range of frequencies and waveforms in order to optimize the performance of the transducer. The counter is compatible with most standard SCA, and is configured as a rate-meter that provides counts per selectable time slice at the programmed velocity. As a demonstration of the instrument applications, a partial Moessbauer spectrum of a natural iron foil was taken. Only positive energies were studied in 512 channels, accumulating 20 s per channel. A line width of 0.20 mm/s was achieved, performing with an efficiency of 80%.

  12. The Unusual Moessbauer Spectrum of Beryl

    Viana, R. R.; Costa, G. M. da; Grave, E. de; Evangelista, H. J.; Stern, W. B.

    2001-01-01

    The Moessbauer spectra of several aquamarine samples have been obtained in the temperature range of 4.2-500 K. A common feature observed in all room-temperature spectra is the presence of an asymmetric Fe 2+ doublet (ΔE Q ∼2.7 mm/s, δ∼1.1 mm/s), with a very broad low-velocity peak. This asymmetry is not caused by preferred orientation since the spectrum collected under the magic angle did not show any difference in the line intensities, nor is it caused by the superposition of a Fe 3+ doublet. At 4.2 K the spectrum of a deep-blue beryl could be well fitted with three symmetrical doublets, with the major Fe 2+ doublet accounting for 87% of the total spectral area. At 14 K the symmetry remains, but at 30 K the low-velocity peak is again broad. Surprisingly, the spectrum at 500 K also shows a broad, but symmetrical doublet, with a clear splitting of the lines indicating the presence of at least two Fe 2+ components. The room-temperature spectrum obtained after the 500 K run shows the same features as before the heating. A meaningful fit for the room-temperature spectrum, as well as an explanation for the temperature dependence of the Moessbauer spectra, are discussed

  13. Clinical and Insurance Perspectives on Intermediate Levels of Care in Psychiatry.

    Plakun, Eric M

    2018-03-01

    This column compares a clinical perspective on the continuum of care for mental health and substance use disorders with a different perspective derived from publicly available insurance company documents and experience dealing with managed care utilization reviewers. The latter perspective tends to determine the need for access to levels of care based on the need for crisis stabilization, whereas the generally accepted clinical standard is more nuanced than the need for crisis stabilization alone. The column proposes that this discrepancy in perspectives makes a substantial contribution to disagreements between treating clinicians, such as therapists, and insurance utilization reviewers concerning the medical necessity of various requested levels of care.

  14. Teacher cognition and the teaching of EFL reading at the Norwegian intermediate level

    Gilje, Trine Mathiesen

    2011-01-01

    Master's thesis in Literacy studies The development of reading skills in English as a Foreign Language classrooms at the elementary level, the way in which teachers of English implement the LK06 learning objectives in reading, and the influence of teachers´attitudes, beliefs, and knowledge on their classroom practices and decisions.

  15. Resistance of Feather-Associated Bacteria to Intermediate Levels of Ionizing Radiation near Chernobyl

    Ruiz-Gonz?lez, Mario Xavier; Czirj?k, G?bor ?rp?d; Genevaux, Pierre; M?ller, Anders Pape; Mousseau, Timothy Alexander; Heeb, Philipp

    2016-01-01

    Ionizing radiation has been shown to produce negative effects on organisms, although little is known about its ecological and evolutionary effects. As a study model, we isolated bacteria associated with feathers from barn swallows Hirundo rustica from three study areas around Chernobyl differing in background ionizing radiation levels and one control study site in Denmark. Each bacterial community was exposed to four different ? radiation doses ranging from 0.46 to 3.96 kGy to test whether ch...

  16. Restoring NAD(+) Levels with NAD(+) Intermediates, the Second Law of Thermodynamics and Aging Delay.

    Poljsak, Borut; Milisav, Irina

    2018-04-26

    The hypothesis regarding the role of increased nicotinamide adenine dinucleotide (NAD+) levels with reference to the fundamental concepts of ageing and entropy is presented. Considering the second law of thermodynamics, NAD+ seems the appropriate candidate for reversing many aging-associated pathologies. NAD+ is presented as an essential compound that enables organisms to stay highly organized and well-maintained, with a lower entropy state.

  17. Passive Avoidance Training and Recall are Associated With Increased Glutamate Levels in the Intermediate Medial Hyperstriatum Ventrale of the Day-Old Chick

    Jonathan N. Daisley

    1998-01-01

    glutamate levels in the intermediate medial hyperstriatum ventrale accompany pecking at either the water- or the methylanthranylate-bead. The taste of the aversant may be responsible for the greater increases found in methylanthranylate-trained birds.

  18. Reflections of Turkish accounting and financial reporting standards on vocational school students: A research on comparing perceptions of intermediate and mid-level accounting professional candidates

    Seldüz Hakan; Seldüz Emine

    2016-01-01

    This research aims to compare the perceptions of intermediate and mid-level accounting professional candidates on accounting and financial reporting standards. A significant part of accounting process is carried out by vocational school graduate intermediate and mid-level accounting professionals. However, it can be claimed that adequate education about accounting and financial reporting standards isn’t given in vocational schools although these standards structure the whole accounting proces...

  19. Risks assessment associated with the possibility of intrusion into the low and intermediate level waste disposal facility

    Didita, L.; Ilie, P.; Pavelescu, M.

    1997-01-01

    In post-closure performance assessment of low and intermediate level waste disposal facilities it is necessary to assess the individual risks associated with the possibility of intrusion into repository. Intruder induced disruptive events can potentially compromise the integrity of the disposal unit and result in exhumation of the waste and radionuclides migration into environment. In this way, the main routes of exposure are: -inhalation of radioactive materials by the intruder; - external gamma irradiation of the intruder, - long-term pathways resulting from the transfer of radioactive materials to the surface of the site. This paper describes the evaluation of conditional and absolute risks associated with each route of exposure as a function of time. To evaluate the risks, it is necessary to calculate the time-dependent activities of each nuclide considered. This is achieved by employing an analytic solution to the Bateman equation at specified times of evaluation. Conditional risks by inhalation, external exposure and long-term pathways and different modes of intrusion are evaluated on the basis of an annual probability of intrusion of unity. Absolute risks are calculated by scaling the user-supplied probabilities of intrusion at various times of evaluation. The evaluation of absolute risks by long-term exposure pathways involves an interpolation procedure in time. The calculations have been performed for the most important radionuclides present in low and intermediate wastes. (authors)

  20. Policy considerations of low-level and intermediate-level radioactive wastes from a public interest perspective

    Rodgers, S.

    1977-01-01

    A critical, environmentalist view is taken of the problem of low-level radioactive waste disposal. Policy questions and needs for additional data are listed. The lack of a requirement for environmental impact statements prior to site licensing is pointed out. Some of New Mexico's experiences are briefly recounted. The need for definitions for radioactive wastes is pointed out

  1. Crystal structures and Moessbauer spectra of spin-crossover iron(III) complexes of quinquedentate ligands

    Maeda, Yonezo; Noda, Yosuke; Oshio, Hiroki; Takashima, Yoshimasa; Matsumoto, Naohide

    1994-01-01

    Magnetic properties, Moessbauer spectra and crystal structures of spin-crossover iron(III) complexes with a quinquedentate ligand [FeLX]BPh 4 are reported. X and L denote a unidentate ligand and a quinquedentate ligand, respectively. [Fe(mbpN)(im)]BPh 4 shows spin-crossover behavior in an appropriate organic solvent, and [Fe(mbpN)(lut)]BPh 4 , [Fe(bpN)(py)]BPh 4 and [Fe(salten)X]BPh 4 (X = 4me-py or 2me-im) show spin-crossover behavior in a solid and in an organic solvent. It was found that the ligand field strength of salten was stronger than that of mbpN. The rates of spin-state interexchange in the complexes are as fast as the inverse of the lifetime (1 x 10 -7 s) of the Moessbauer nuclear level. The Moessbauer spectroscopic behavior of [Fe(mbpN)(lut)]BPh 4 and [Fe(bpN)(py)]BPh 4 is different to that of [Fe(salten)X]BPh 4 (X = 4me-py or 2me-im). The difference was ascribed to the different geometrical positions of the corresponding anions. (orig.)

  2. Moessbauer effects on oriented nuclei

    Sayouti, E.H.

    1984-01-01

    Standard nuclear orientation methods (not sensitive to the polarization) do not give information on the sign of the magnetic moment. Mossbauer effect separates right-hand and left-hand circularly polarized components, thus its detection on oriented nuclei (T approximately 10 mK) gives the sign of the magnetic moment of oriented state. In this thesis we applied this method to study the 3/2 - ground states of 191 Pt and 193 Os, which are in the prolate-oblate transition region, where assignement of experimental levels to theoretical states is often umbiguous. We show that for those nuclei the sign of the magnetic moment is the signature of the configuration, and its determination establishes the correspondance between experimental and theoretical levels [fr

  3. Moessbauer backscatter spectrometer with full data processing capability

    1976-01-01

    The design and operation of a Moessbauer backscatter spectrometer with full data processing capability is described, and the investigation of the applicability of this technique to a variety of practical metallurgical problems is discussed

  4. Latin American conference on the applications of the Moessbauer effect

    1992-01-01

    This work includes all the papers presented at the LACAME'92 Latin American conference on the applications of the Moessbauer effect, held in Buenos Aires (Argentine Republic), from 5th. through 9th., 1992

  5. Moessbauer studies on ancient Jizhon plain Temmoku porcelains

    Yu Zhengfang; Zheng Yufang; Lin Yongqiang

    1994-01-01

    Three kinds of ancient Jizhou plain Temmoku wares and their several ware-making raw materials were studied by means of X-ray diffraction (XRD) and Moessbauer spectroscopy. The firing technique of ancient Jizhou Temmoku porcelains is discussed. (orig.)

  6. An electrostatic RF modulator for Moessbauer gamma-rays

    Ognjanov, N.I.; Tsankov, L.T.; Ivanov, P.V.

    1983-01-01

    A new device is proposed for rf acoustic modulation of Moessbauer gamma-radiation, based on the principle of the electrostatic speaker. Certain features of the construction are discussed and results from tests are presented. (orig.)

  7. Proceedings of the 1. National Meeting of Moessbauer Spectroscopy

    1982-01-01

    Several works, both theoretical and experimental, on Moessbauer effect which have been done by Brazilian physical groups are presented in this meeting. The historical evolution of this field in Brazil is also approached. (L.C.) [pt

  8. Moessbauer study of amorphous Fe-P alloys

    Takacs, L.; Toth-Kadar, E.

    1981-01-01

    Preliminary Moessbauer results are represented on electrodeposited Fe-P amorphous alloys. Very broad hyperfine field distributions and relatively large isomer shifts have been found. Problems worth of further investigation are discussed in details. (author)

  9. Application of Moessbauer effect in identification of minerals

    Gajdosova, M.

    1979-01-01

    An analysis is made of the Moessbauer spectra of magnetites from the Ocna de Fier deposit in Romania, from the deposits of Kiruna and Taberg in Sweden and from the deposit in the Ural in the USSR. (H.S.)

  10. Study on Moessbauer spectra of hemoglobin in thalassemia

    Guo Xuanhui; Zhao Nanming; Zhang Xiufang

    1988-01-01

    The 57 Fe Moessbauer spectra of erythrocytes in normal subjects and nine patients of different thalassemias were studied. Together with clinical analysis, the correlation between the components in the spectra and different types of anemias was discussed. (orig.)

  11. The design of a servo system for a Moessbauer spectrometer

    Cranshaw, T.E.

    1981-06-01

    This report describes the design of a transducer system and servo drive amplifier suitable for Moessbauer spectrometers. Particular attention is paid to low and zero frequency drift. Measurements of the loop gain of a practical system are presented. (author)

  12. Radiocarbon signal of a low and intermediate level radioactive waste disposal facility in nearby trees.

    Janovics, R; Kelemen, D I; Kern, Z; Kapitány, S; Veres, M; Jull, A J T; Molnár, M

    2016-03-01

    Tree ring series were collected from the vicinity of a Hungarian radioactive waste treatment and disposal facility and from a distant control background site, which is not influenced by the radiocarbon discharge of the disposal facility but it represents the natural regional (14)C level. The (14)C concentration of the cellulose content of tree rings was measured by AMS. Data of the tree ring series from the disposal facility was compared to the control site for each year. The results were also compared to the (14)C data of the atmospheric (14)C monitoring stations at the disposal facility and to international background measurements. On the basis of the results, the excess radiocarbon of the disposal facility can unambiguously be detected in the tree from the repository site. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. A product designed for final disposal of low and intermediate level radioactive wastes

    Baboescu, E.; Popescu, I. V.

    2001-01-01

    The product 'metallic barrel - concrete - low level radioactive wastes - 1' (ABBD - 1) was certified according to the company's standard SF ICN/1994, updated 1. The product ABBD -1 is produced according to the following certified technologies: - technology for processing and conditioning of low level radioactive solid wastes; - technology for processing and conditioning of waste ion exchangers from the TRIGA reactor; - technology for conditioning the β - γ radioactive compacts. The product is constituted of a protection shield, the concrete block - radioactive waste, securing high mechanical strength and a high degree of radionuclides retaining, thus ensuring the necessary condition for long time disposal and, finally, the metallic container fulfilling the National Standards of Nuclear Safety for Radioactive Materials Transportation. The metallic container is made of pickled slab, with a 220 l capacity, according to STAS 7683/88 standards. The main characteristics of the product 'ABBD - 1' are: - size: height, 915 ± 10 mm, diameter, 600 ± 5 mm; - mass, 300 - 600 kg; - maximum permissible activity, 6 x 10 9 Bq/ barrel (0.164 Ci/barrel); - equivalent dose rate for gamma radiation at barrel's wall, max. 1 mSv/h (200 mrem/h); - unfixed external contamination, 2 ; - compression strength of concrete block alone, > 5 x 10 6 N/m 2 ; - lixiviation rate, -3 cm/day; - the compact concrete block-radioactive waste is leak-proof and crack-free. The final product is transferred from INR Pitesti to National Repository for Radioactive Waste by railway and road transportation according to the provisions of the National Commission for Nuclear Activity Control as stipulated in the National Standards of Nuclear Safety of Radioactive Materials Transportation

  14. Intermediate and high level earthquakes testing at the HDR - overview, objectives, results

    Jehlicka, P.; Malcher, L.

    1981-01-01

    The main objective of these earthquake investigations is the verification of calculation methods relating to structure dynamics which are used for the seismic design of nuclear power plants. Structures analyzed by tests and precalculations were the reactor building, the reactor pressure vessel, two large-diameter piping systems and one of the flood water tanks. Excitation methods used were eccentric mass shakers, snapback devices, explosives and solid propellant rockets. Some of the tests involving excitation of the building by shakers and two of the blast tests were carried out with the reactor pressure vessel and the pipes under operating conditions. The precalculations using both linear and nonlinear methods were made by German industry groups, independent experts groups and international partners. Soil-structure interaction can be determined accurately by means of simplified methods using frequency dependent soil springs. The reduction in the eigenfrequencies of the building when the load was increased by a factor of 25 could be predicted. Comparison of the results obtained for the vibrational behaviour of the building show that a simplification to the rotationally symmetric shell model appears to be a reasonable compromise between simple beam models and sophisticated 3D-shell models. The strong decrease in eigenfrequencies observed in the experiments during the transition from empty to partly filled reactor pressure vessel, and the resultant change of the mode shapes was perfectly reflected if the virtual mass of water was introduced in the calculation. Damping values evaluated from the measurements demonstrate that for some structures damping can remain low, even at levels of response leading to local yielding, while for other structures damping was very high at a rather low level of response. It appears that the use of generalized damping values for the seismic analysis of mechanical and structural systems is not appropriate. (orig./HP)

  15. Quantitative analysis of Moessbauer backscatter spectra from multilayer films

    Bainbridge, J.

    1975-01-01

    The quantitative interpretation of Moessbauer backscatter spectra with particular reference to internal conversion electrons has been treated assuming that electron attenuation in a surface film can be satisfactorily described by a simple exponential law. The theory of Krakowski and Miller has been extended to include multi-layer samples, and a relation between the Moessbauer spectrum area and an individual layer thickness derived. As an example, numerical results are obtained for a duplex oxide film grown on pure iron. (Auth.)

  16. Compact cryogenic attachment for Moessbauer spectroscopy with microwave excitation

    Didenko, N.P.; Amelin, G.P.; Zelentsov, V.I.; Kaminskii, V.L.; Fedorov, N.P.; Fal'kovich, V.M.

    1989-01-01

    A compact cryogenic attachment is described that is placed on a standard helium Dewar flask and permits recording of Moessbauer spectra with excitation by millimeter-band radiation in the temperature range of 4.3-300 K. The design of the attachment allows operation with various gamma-radiation detectors in both horizontal and vertical Moessbauer measurement geometries and its placement in superconducting magnets with a large warm zone

  17. Moessbauer Study of Discoloration of Synthetic Resin Covered Electric Switches

    Kuzmann, E.; Muzsay, I.; Homonnay, Z.; Vertes, A.

    2002-01-01

    57 Fe Moessbauer spectroscopy and X-ray diffractometry were used to investigate brown discoloration and sediments formed on the surface of synthetic resin product covered electronic switches. The Moessbauer measurement revealed that alloyed steels and iron-containing corrosion products are associated with the discolored layers. Iron, and iron corrosion products were shown by both MS and XRD in the sediments formed eventually during the finishing of the synthetic resin products after machining and washing with water solution.

  18. Moessbauer analysis of recent ceramic finds from Chavin

    Wagner, U.; Wagner, F.E.; Stockklauser, A.; Salazar, R.; Riederer, J.; Kauffmann-Doig, F.

    1986-01-01

    A large number of ceramic sherds from Chavin, Peru, as well as recent clay samples from the same region have been studied by Moessbauer spectroscopy. The changes of the Moessbauer spectra of the clay were studied as a function of firing temperature and atmosphere. From a comparison of these data with those from the sherds one can make estimates of the precolumbian firing conditions. (Auth.)

  19. Moessbauer study of sediment alteration produced by heat treatment

    Labenski de Kanter, F.; Duhalde, S.; Saragovi, C.; March, R.J.

    1994-01-01

    Pincenvent (France) cooking-place silt-like sediments have been studied by using Moessbauer spectroscopy and characterized by using X-ray diffraction (XRD). The sediments were treated at 400, 600, 800 and 1000 C under oxidizing conditions. We discuss the results and we suggest a ''Moessbauer thermometer'' to be used to recognize the temperatures and atmosphere ancient people used in their cooking-places. (orig.)

  20. The Moessbauer effect in binary tin chalcogenides of tin 119

    Ortalli, I.; Fano, V.

    1975-01-01

    The values of the isomer shift, quadrupole splitting, Moessbauer coefficient, Debye temperature for the tin chalcogenides SnS. SnSe, SnTe are tabulated for the temperatures 80 and 300 K. Temperature dependences of the Moessbauer coefficient and of the effective Debye temperature for SnS, SnSe and SnTe in a temperature range of 78 to 300 K are presented. (Z.S.)

  1. Moessbauer investigation of maghemite-based glycolic acid nanocomposite

    Santos, J. G.; Silveira, L. B.; Oliveira, A. C.; Garg, V. K.; Lacava, B. M.; Tedesco, A. C.; Morais, P. C.

    2007-01-01

    Transmission electron microscopy, X-ray diffraction and Moessbauer spectroscopy were used in the characterization of a nanocomposite containing magnetic nanoparticles dispersed in a glycolic acid-based template. Maghemite nanoparticles were identified as the iron oxide phase dispersed in the polymeric template. From the low-temperature Moessbauer data the amount of the iron-based, non-magnetic material at the nanoparticle surface was estimated as roughly one monolayer in thickness.

  2. Predisposal management of low and intermediate level radioactive waste. Safety guide

    2003-01-01

    considered in this publication begins with the refining and conversion of uranium concentrates. Recommendations on the management of radioactive waste from the mining and milling of uranium and thorium ores are provided. Some parts of the nuclear fuel cycle generate both high level waste and LLW. The management of high level waste itself generates LLW. The predisposal management of this LLW is included in the scope of this Safety Guide. Recommendations on the predisposal management of high level waste are provided. The recommendations in this Safety Guide primarily concern complex management activities for LLW. The regulatory body should decide which parts of this Safety Guide are relevant and appropriate for particular circumstances, and the extent to which the recommendations and guidance apply. This Safety Guide provides only introductory material on the transport and storage of LLW. Requirements and recommendations are provided in Refs. There may be non-radiological hazards associated with the predisposal management of LLW. Some guidance is given on the safety measures to be taken against non-radiological hazards if they have potential consequences for radiation safety. However, detailed recommendations are beyond the scope of this Safety Guide. The user should seek guidance from the regulatory body in the areas of health and safety and environmental protection

  3. Striatal response to reward anticipation: evidence for a systems-level intermediate phenotype for schizophrenia.

    Grimm, Oliver; Heinz, Andreas; Walter, Henrik; Kirsch, Peter; Erk, Susanne; Haddad, Leila; Plichta, Michael M; Romanczuk-Seiferth, Nina; Pöhland, Lydia; Mohnke, Sebastian; Mühleisen, Thomas W; Mattheisen, Manuel; Witt, Stephanie H; Schäfer, Axel; Cichon, Sven; Nöthen, Markus; Rietschel, Marcella; Tost, Heike; Meyer-Lindenberg, Andreas

    2014-05-01

    Attenuated ventral striatal response during reward anticipation is a core feature of schizophrenia that is seen in prodromal, drug-naive, and chronic schizophrenic patients. Schizophrenia is highly heritable, raising the possibility that this phenotype is related to the genetic risk for the disorder. To examine a large sample of healthy first-degree relatives of schizophrenic patients and compare their neural responses to reward anticipation with those of carefully matched controls without a family psychiatric history. To further support the utility of this phenotype, we studied its test-retest reliability, its potential brain structural contributions, and the effects of a protective missense variant in neuregulin 1 (NRG1) linked to schizophrenia by meta-analysis (ie, rs10503929). Examination of a well-established monetary reward anticipation paradigm during functional magnetic resonance imaging at a university hospital; voxel-based morphometry; test-retest reliability analysis of striatal activations in an independent sample of 25 healthy participants scanned twice with the same task; and imaging genetics analysis of the control group. A total of 54 healthy first-degree relatives of schizophrenic patients and 80 controls matched for demographic, psychological, clinical, and task performance characteristics were studied. Blood oxygen level-dependent response during reward anticipation, analysis of intraclass correlations of functional contrasts, and associations between striatal gray matter volume and NRG1 genotype. Compared with controls, healthy first-degree relatives showed a highly significant decrease in ventral striatal activation during reward anticipation (familywise error-corrected P systems-level functional phenotype is reliable (with intraclass correlation coefficients of 0.59-0.73), independent of local gray matter volume (with no corresponding group differences and no correlation to function, and with all uncorrected P values >.05), and affected by

  4. Moessbauer Spectroscopy: Elegance and versatility in chemical diagnostics

    Guetlich, Philipp; Garcia, Yann, E-mail: guetlich@uni-mainz.d [Unite de Chimie des Materiaux Inorganiques et Organiques, Departement de Chimie, Universite Catholique de Louvain, Place L. Pasteur 1, 1348 Louvain la Neuve (Belgium)

    2010-03-01

    Dedicated to Professor Rudolf Ludwig Moessbauer on the occasion of his 80th birthday. Soon after the discovery of the recoilless nuclear resonance fluorescence by Rudolf L. Moessbauer some fifty years ago a new spectroscopic technique developed quickly on the basis of this resonance phenomenon as an excellent tool for the investigation of materials through electric and magnetic hyperfine interactions between electrons and suitable Moessbauer nu-clides. Many disciplines of solid state research have benefited from applications of the new tool for non-destructive phase analysis. Chemists in particular have recognized the information that can be derived from Moessbauer spectra regarding oxidation and spin state, molecular symmetry, bonding properties, magnetism, dynamic phenomena such as spin state switching, electronic transfer processes and other phase fluctuations to name a few. This Keynote Lecture presents highlights of chemical applications of Moessbauer spectroscopy selected from work during the past five decades which will demonstrate the elegance and versatility of the technique in the hands of (not only) chemists, but materials scientists in the broadest sense. The retrospect begins with studies in the early sixties on simple oxides and coordination compounds, where Moessbauer spectroscopy played a decisive role in solving unanswered questions, and concludes with fascinating current discoveries on the Planet Mars and most recent developments in the use of synchrotron radiation for nuclear resonance scattering (NFS, NIS).

  5. Mechanisms and Kinetics of Organic Aging and Characterization of Intermediates in High-Level Waste

    Camaioni, Donald M.; Autrey, S. Tom; Dupuis, Michel; Shaw, Wendy

    2002-01-01

    The objective of this project is to characterize significant chemical degradation pathways of organic chemicals in nuclear waste storage and treatment streams. The effort at Pacific Northwest National Laboratory (PNNL) is closely coordinated with a Notre Dame Radiation Laboratory project (EMSP No. 73832, ''The NOx System in Nuclear Waste'', D. Meisel, Principal Investigator) that focuses on radiolytically induced degradation of organic complexants. An understanding of the chemistry of the organic chemicals present in tank wastes is needed to manage the wastes and related site cleanup activities. The underlying chemistries of high-level waste are (1) the chemistry initiated by radioactive decay and the reactions initiated by heat from radioactive decay and (2) the chemistry resulting from waste management activities (waste transfers between tanks, concentration through evaporators, caustic and other chemical additions). Recognizing that experiments cannot reproduce every conceivable scenario, the PNNL and Notre Dame projects work to develop predictive computational models of these chemistries. Participants in both projects combine experimental observations, electronic structure computations, and theoretical methods developed to achieve this goal. The resulting model will provide an accurate evaluation of the hazardous material generated, including flammable gases, and will support decision-making processes regarding safety, retrieval, and treatment issues. The utility of developing an understanding of tank chemistry has been demonstrated in earlier work. None of the Hanford tanks is currently on a watch list, partially due to predictive understanding of organic aging and flammable gas generation that resulted from previous research. Furthermore, concerns that arise from pretreatment and tank closure issues (e.g., Tc speciation) may be rationalized with the mechanistic knowledge provided by these projects

  6. Prediction and assessment of environmental impacts of Guangdong low-and-intermediate level radioactive waste disposal site

    Huang Yawen

    1996-01-01

    Guangdong Low-and Intermediate Level Radioactive Waste Disposal Site is located 5-7 km northeast to the Daya Bay Nuclear Power Plant. It is in a hilly area with strongly weathered light metamorphic quartz siltstone. The groundwater is 2 m below the repository bottom. The disposal unit is a U-shape concrete structure with drainage and water collecting system at the bottom. The designed cover is a multi-layer structure with functions of preventing from water infiltration, animal and plant intrusion. It is assumed that the engineered barriers would be effective to avoid waste immersion by surface water and groundwater within the first 100 years after closure. After 100 years, the engineered barriers would fail gradually. Radionuclides may release from the disposal unite. Some will enter the nearby stream, some will flow into the Daya Bay, and some will transport to groundwater through geologic media

  7. A preliminary assessment of polymer-modified cements for use in immobilisation of intermediate level radioactive waste

    Burnay, S.G.; Dyson, J.R.

    1982-11-01

    A range of polymer-modified cements has been examined as candidate materials for the immobilisation of intermediate level radioactive waste. The waste streams studied were inactive simulates of real wastes and included ion-exchange resins, Magnox debris and dilute sludges. Preliminary experiments on the compatibility of the polymer-cement-waste combinations have been carried out and measurements of flexural strength before and after #betta#-irradiation to 10 9 rad and water immersion have been made. Soxhlet leach tests have been used to compare the leach rates of the different materials. From the results of these preliminary experiments, a limited number of polymer-modified cements have been suggested as suitable for more detailed study. (author)

  8. Inventories of organic materials and complexing agents in intermediate-level long-lived parcels (Report PNGMDR 2013-2015)

    2014-01-01

    This report presents an inventory of organic materials and of complexing agents they may produce within parcels of alpha wastes which are to be produced or are being currently produced. The report proposes the results of campaigns of measurements of degassing, and comparison with results of modelling studies. The assessment of degassing rates of parcels of alpha wastes is completed by an assessment of hydrogen produced by radiolysis of interstitial water within the concrete container. Thus, after a presentation of the main parcels used by the CEA for intermediate-level long-lived wastes, and of an inventory of wastes containing organic materials, this report describes the consequences of radiolysis on polymers, and describes the objectives of R and D studies. It reports measurements and presents simulation tools for heterogeneous wastes, homogeneous wastes, production of water-soluble degradation products, and transfer and adsorption of these products in the storage site argillite

  9. A Study on Optimized Management Options for the Wolsong Low- and Intermediate - Level Waste Disposal Center in Korea - 13479

    Park, JooWan; Kim, DongSun; Choi, DongEun [Korea Radioactive Waste Management Corporation, Korea 89, Bukseongno, Gyeongju, 780-050 (Korea, Republic of)

    2013-07-01

    The safe and effective management of radioactive waste is a national task required for sustainable generation of nuclear power and for energy self-reliance in Korea. Currently, for permanent disposal of low- and intermediate-level waste (LILW), the Wolsong LILW Disposal Center (WLDC) is under construction. It will accommodate a total of 800,000 drums at the final stage after stepwise expansion. As an implementing strategy for cost-effective development of the WLDC, various disposal options suitable for waste classification schemes would be considered. It is also needed an optimized management of the WLDC by taking a countermeasure of volume reduction treatment. In this study, various management options to be applied to each waste class are analyzed in terms of its inventory and disposal cost. For the volume reduction and stabilization of waste, the vitrification and plasma melting methods are considered for combustible and incombustible waste, respectively. (authors)

  10. Hydration products and mechanical properties of hydroceramics solidified waste for simulated Non-alpha low and intermediate level radioactive wastes

    Wang Jin; Hong Ming; Wang Junxia; Li Yuxiang; Teng Yuancheng; Wu Xiuling

    2011-01-01

    In this paper, simulated non-alpha low and intermediate level radioactive wastes was handled as curing object and that of 'alkali-slag-coal fly ash-metakaolin' hydroceramics waste forms were prepared by hydrothermal synthesis method. The hydration products were analyzed by X ray diffraction. The composition of hydrates and the compressive strength of waste forms were determined and measured. The results indicate that the main crystalline phase of hydration products were analcite when the temperature was 150 to 180 degree C and the salt content ratio was 0.10 to 0.30. Analcite diffraction peaks in hydration products is increasing when the temperature was raised and the reaction time prolonged. Strength test results show that the solidified waste forms have superior compressive strength. The compressive strength gradually decreased with the increase in salt content ratio in waste forms. (authors)

  11. Low- and intermediate level radioactive waste from Risoe, Denmark. Site studies. Report no. 5. Thise, Skive Municipality

    Gravesen, P.; Nilsson, B.; Binderup, M.; Larsen, Tine; Schack Pedersen, S.A.

    2012-01-01

    The low- and intermediate-level radioactive wastes from Risoe (the nuclear reactor buildings, different types of material from the research periods and waste from hospitals and research institutes) have to be stored in a final disposal in Denmark for at least 300 years. In 2011, the results of the first analyses of 20 potential areas for siting a waste disposal were published. Of these potential areas, 6 specific sites were selected for further detailed studies. The site studies include information about geology, land use, nature preservation, archaeology, drinking water supply etc. The 5 municipalities with the 6 selected sites have been visited to obtain as much information about local conditions as possible. The present report describes the results for the area Thise, in the Municipality of Skive, northern Jutland. (LN)

  12. Low- and intermediate level radioactive waste from Risoe, Denmark. Site studies. Report no. 2. Roedbyhavn, Lolland Municipality

    Gravesen, P.; Nilsson, B.; Binderup, M.; Larsen, Tine; Schack Pedersen, S.A.

    2012-01-01

    The low- and intermediate-level radioactive wastes from Risoe (the nuclear reactor buildings, different types of material from the research periods and waste from hospitals and research institutes) have to be stored in a final disposal in Denmark for at least 300 years. In 2011, the results of the first analyses of 20 potential areas for siting a waste disposal were published. Of these potential areas, 6 specific sites were selected for further detailed studies. The site studies include information about geology, land use, nature preservation, archaeology, drinking water supply etc. The 5 municipalities with the 6 selected sites have been visited to obtain as much information about local conditions as possible. The present report describes the results for the area at Roedbyhavn in the Municipality of Lolland, southern Denmark. (LN)

  13. Low- and intermediate level radioactive waste from Risoe, Denmark. Site studies. Report no. 3. Kertinge Mark, Kerteminde Municipality

    Gravesen, P.; Nilsson, B.; Binderup, M.; Larsen, Tine; Schack Pedersen, S.A.

    2012-01-01

    The low- and intermediate-level radioactive wastes from Risoe (the nuclear reactor buildings, different types of material from the research periods and waste from hospitals and research institutes) have to be stored in a final disposal in Denmark for at least 300 years. In 2011, the results of the first analyses of 20 potential areas for siting a waste disposal were published. Of these potential areas, 6 specific sites were selected for further detailed studies. The site studies include information about geology, land use, nature preservation, archaeology, drinking water supply etc. The 5 municipalities with the 6 selected sites have been visited to obtain as much information about local conditions as possible. The present report describes the results for the area Kertinge Mark in the Municipality of Kerteminde, the island Funen. (LN)

  14. Low- and intermediate level radioactive waste from Risoe, Denmark. Site studies. Report no. 4. Hvidbjerg, Thyholm, Struer Municipality

    Gravesen, P.; Nilsson, B.; Binderup, M.; Larsen, Tine; Schack Pedersen, S.A.

    2012-01-01

    The low- and intermediate-level radioactive wastes from Risoe (the nuclear reactor buildings, different types of material from the research periods and waste from hospitals and research institutes) have to be stored in a final disposal in Denmark for at least 300 years. In 2011, the results of the first analyses of 20 potential areas for siting a waste disposal were published. Of these potential areas, 6 specific sites were selected for further detailed studies. The site studies include information about geology, land use, nature preservation, archaeology, drinking water supply etc. The 5 municipalities with the 6 selected sites have been visited to obtain as much information about local conditions as possible. The present report describes the results for the area Hvidbjerg, Thyholm, in the Municipality of Struer, northern Jutland. (LN)

  15. Low- and intermediate level radioactive waste from Risoe, Denmark. Site studies. Report no. 6. Skive Vest, Skive Municipality

    Gravesen, P.; Nilsson, B.; Binderup, M.; Larsen, Tine; Schack Pedersen, S.A.

    2012-01-01

    The low- and intermediate-level radioactive wastes from Risoe (the nuclear reactor buildings, different types of material from the research periods and waste from hospitals and research institutes) have to be stored in a final disposal in Denmark for at least 300 years. In 2011, the results of the first analyses of 20 potential areas for siting a waste disposal were published. Of these potential areas, 6 specific sites were selected for further detailed studies. The site studies include information about geology, land use, nature preservation, archaeology, drinking water supply etc. The 5 municipalities with the 6 selected sites have been visited to obtain as much information about local conditions as possible. The present report describes the results for the area Skive Vest, in the Municipality of Skive, northern Jutland. (LN)

  16. Low- and intermediate level radioactive waste from Risoe, Denmark. Site studies. Report no. 1. Oestermarie - Paradisbakkerne, Bornholm Region

    Gravesen, P.; Nilsson, B.; Binderup, M.; Larsen, Tine; Schack Pedersen, S.A.

    2012-01-01

    The low- and intermediate-level radioactive wastes from Risoe (the nuclear reactor buildings, different types of material from the research periods and waste from hospitals and research institutes) have to be stored in a final disposal in Denmark for at least 300 years. In 2011, the results of the first analyses of 20 potential areas for siting a waste disposal were published. Of these potential areas, 6 specific sites were selected for further detailed studies. The site studies include information about geology, land use, nature preservation, archaeology, drinking water supply etc. The 5 municipalities with the 6 selected sites have been visited to obtain as much information about local conditions as possible. The present report describes the results for the area at Oestermarie-Paradisbakkerne in the region of Bornholm, East Denmark. (LN)

  17. Smooth driving of Moessbauer electromechanical transducers

    Veiga, A., E-mail: veiga@fisica.unlp.edu.ar; Mayosky, M. A. [Universidad Nacional de La Plata, Facultad de Ingenieria (Argentina); Martinez, N.; Mendoza Zelis, P.; Pasquevich, G. A.; Sanchez, F. H. [Instituto de Fisica La Plata, CONICET (Argentina)

    2011-11-15

    Quality of Moessbauer spectra is strongly related to the performance of source velocity modulator. Traditional electromechanical driving techniques demand hard-edged square or triangular velocity waveforms that introduce long settling times and demand careful driver tuning. For this work, the behavior of commercial velocity transducers and drive units was studied under different working conditions. Different velocity reference waveforms in constant-acceleration, constant-velocity and programmable-velocity techniques were tested. Significant improvement in spectrometer efficiency and accuracy was achieved by replacing triangular and square hard edges with continuous smooth-shaped transitions. A criterion for best waveform selection and synchronization is presented and attainable enhancements are evaluated. In order to fully exploit this driving technique, a compact microprocessor-based architecture is proposed and a suitable data acquisition system implementation is presented. System linearity and efficiency characterization are also shown.

  18. Moessbauer spectroscopy in studies of photosynthesis

    Burda, Kvetoslava

    2008-01-01

    Photosynthesis is a process occurring in certain species of bacteria, algae and higher plants. It transforms solar energy into various forms of energy-rich organic molecules. Photosystem II (PSII) is the 'heart' of the photosynthetic apparatus because it delivers electrons and protons for further steps of the light-driven phases of photosynthesis. There are two enigmatic iron binding structures within the core of photosynthetic apparatus, which play an important role in the electron transfer within PSII. Many investigations focus on the determination of their function which is the key to the understanding of the molecular mechanism of the energy and electron transfer within PSII. Among many methods used in this research field, the Moessbauer spectroscopy is a unique one, which gives the possibility to study changes of the valence and spin states of those two iron sites and the dynamical properties of their protein matrix in the presence of various physiological and stress conditions.

  19. Moessbauer investigations of palygorskite from Xuyi, China

    Huang Yanjun; Li Zhen; Li Shuzhen; Shi Ziliang; Yin Lin; Hsia Yuanfu

    2007-01-01

    The original palygorskite clay mineral has been collected from Longwangshan, Xuyi, Jiangsu Province, China. XRF analysis was performed to study its chemical compositions. Thermogravimetric analysis and differential thermogravimetric analysis (TGA/DTA) were used to study the weight loss due to dehydration and dehydroxylation. Then eight samples were prepared by heating at various temperatures. X-ray diffraction (XRD) patterns and Moessbauer spectra were measured to study the crystal evolvement and the occupation of iron cations. It revealed that the iron ions occupied the M1 and M2 with the ratio closed to 3:1. Hematite has been observed when heated at 650 deg. C, which indicated that iron cations mainly occupy M1 sites. An unknown silicate was identified when heated at 750 deg. C and dominated at 850 deg. C

  20. Moessbauer effect and TEM in mineralogy

    Ferrow, E.A.

    1994-01-01

    Moessbauer effect (ME) provides useful information on oxidation state, co-ordination number, co-ordination state, site occupancies, and magnetic properties of Fe-bearing phases. The information gained by ME together with the information provided by other conventional techniques is used to extract temperature, pressure, and kinetics of rock-forming processes. Nevertheless, ME requires that the phases studied are homogeneous over an extremely large volume and that Fe is a major component of the system. Transmission electron microscopy (TEM), on the other hand, provides similar information over a very small volume for a system of any component. However, present TEM spectrometers do not provide sufficient resolution to detect the mixed oxidation state. A complete characterisation of phases in rocks requires, therefore, that conventional techniques be combined with TEM. (orig.)

  1. Birth experience in women with low, intermediate or high levels of fear: findings from the first baby study.

    Elvander, Charlotte; Cnattingius, Sven; Kjerulff, Kristen H

    2013-12-01

    Fear of childbirth and mode of delivery are two known factors that affect birth experience. The interactions between these two factors are unknown. The aim of this study was to estimate the effects of different levels of fear of birth and mode of delivery on birth experience 1 month after birth. As part of an ongoing prospective study, we interviewed 3,006 women in their third trimester and 1 month after first childbirth to assess fear of birth and birth experience. Logistic regression was performed to examine the interactions and associations between fear of birth, mode of delivery and birth experience. Compared with women with low levels of fear of birth, women with intermediate levels of fear, and women with high levels of fear had a more negative birth experience and were more affected by an unplanned cesarean section or instrumental vaginal delivery. Compared with women with low levels of fears with a noninstrumental vaginal delivery, women with high levels of fear who were delivered by unplanned cesarean section had a 12-fold increased risk of reporting a negative birth experience (OR 12.25; 95% CI 7.19-20.86). A noninstrumental vaginal delivery was associated with the most positive birth experience among the women in this study. This study shows that both levels of prenatal fear of childbirth and mode of delivery are important for birth experience. Women with low fear of childbirth who had a noninstrumental vaginal delivery reported the most positive birth experience. © 2013, Copyright the Authors Journal compilation © 2013, Wiley Periodicals, Inc.

  2. Current status of application of Moessbauer effect in geology and mineralogy

    Xu Binfu

    1995-01-01

    The paper briefly introduces the current status of the application of Moessbauer effect in geology and mineralogy. It shows that geology and mineralogy are very active fields in the application of Moessbauer effect

  3. Moessbauer spectroscopy and X-ray diffraction studies of Fe-Ni order-disorder processes in a 35% Ni meteorite (Santa Catharina)

    Scorzelli, R.B.; Danon, J.

    1985-01-01

    The composition and structure of iron-nickel alloys in the Santa Catharina iron meteorite were investigated by metallographic techniques, electron microprobe analysis, Moessbauer spectroscopy and X-ray diffraction. The occurence of an ordered Fe-Ni phase with non-cubic symmetry is demonstrated. This phase is present in large proportions in the Santa Catharina meteorite, and has been identified by its asymmetric Moessbauer spectrum, arising from the presence of a quadrupolar splitting superposed on the magnetic hyperfine splitting. The other major Fe-Ni phase in Santa Catharina gives rise to a single line Moessbauer spectrum with no hyperfine components. X-ray diffraction confirms the presence of the Fe-Ni Llo superstructure in this meteorite. Lattice parameter variations with temperature were found to be identical for the meteorite and for electron irradiated Fe-Ni alloys of the sample composition. Detailed Moessbauer spectroscopy studies from room temperature to liquid helium, and in the presence of external magnetic field show the presence of a smaller amount of another ferromagnetic Fe-Ni phase, probably with disordered structure. The destruction of the superstructure in the Santa Catharina meteorite was investigated after heating the samples. Partial ordering seems to coexist with the disordered phase at intermediate annealing temperatures. At higher temperatures the samples are homogeneous and similar to laboratory produced Fe-Ni alloys with 35% Ni. Order-disorder transformations produced by shock waves and by mechanical treatment are also described. (orig.)

  4. Ageing management program for the Spanish low and intermediate level waste disposal and spent fuel and high-level waste centralised storage facilities

    Zuloaga, P.; Ordoñez, M.; Andrade, C.; Castellote, M.

    2011-04-01

    The generic design of the centralised spent fuel storage facility was approved by the Spanish Safety Authority in 2006. The planned operational life is 60 years, while the design service life is 100 years. Durability studies and surveillance of the behaviour have been considered from the initial design steps, taking into account the accessibility limitations and temperatures involved. The paper presents an overview of the ageing management program set in support of the Performance Assessment and Safety Review of El Cabril low and intermediate level waste (LILW) disposal facility. Based on the experience gained for LILW, ENRESA has developed a preliminary definition of the Ageing Management Plan for the Centralised Interim Storage Facility of spent Fuel and High Level Waste (HLW), which addresses the behaviour of spent fuel, its retrievability, the confinement system and the reinforced concrete structure. It includes tests plans and surveillance design considerations, based on the El Cabril LILW disposal facility.

  5. Ageing management program for the Spanish low and intermediate level waste disposal and spent fuel and high-level waste centralised storage facilities

    Andrade C.

    2011-04-01

    Full Text Available The generic design of the centralised spent fuel storage facility was approved by the Spanish Safety Authority in 2006. The planned operational life is 60 years, while the design service life is 100 years. Durability studies and surveillance of the behaviour have been considered from the initial design steps, taking into account the accessibility limitations and temperatures involved. The paper presents an overview of the ageing management program set in support of the Performance Assessment and Safety Review of El Cabril low and intermediate level waste (LILW disposal facility. Based on the experience gained for LILW, ENRESA has developed a preliminary definition of the Ageing Management Plan for the Centralised Interim Storage Facility of spent Fuel and High Level Waste (HLW, which addresses the behaviour of spent fuel, its retrievability, the confinement system and the reinforced concrete structure. It includes tests plans and surveillance design considerations, based on the El Cabril LILW disposal facility.

  6. Moessbauer effect studies of the recovery of iron after heavy-ion implantation at 7 K

    Reintsema, S.R.; Drentje, S.A.; Waard, H. de

    1978-01-01

    Moessbauer effect measurements were performed with sources of 133 Xe implanted at 7 K in polycrystalline iron foils by means of an isotope separator. Information about the direct environment of an implanted radioactive probe atom is obtained through the hyperfine interaction of the daughter nucleus ( 133 Cs) with its surroundings. The Moessbauer spectra were analyzed on the basis of an earlier model, assuming three visible spectral components with high, intermediate and low hyperfine fields and recoilless fractions, respectively, and a fourth, invisible component with a recoilless fraction very close to zero. Annealing experiments showed no evidence for post-implantation recovery stage I in the iron foils, while recovery stage II only gave rise to small changes in the site occupations. These results can be explained in terms of the high energy density locally deposited in the lattice by each implanted atom, leading to stage I recovery during the very short time that is necessary for the thermal dissipation of this energy. Quantitatively, these results are confirmed by calculations of Sigmund on heavy-ion induced elastic-collision spikes in solids. After annealing at room temperature the site occupations agree with those obtained directly with room temperature implanted sources. In previous experiments it has been shown that different results are obtained for annealing and for implantation at 200 0 C. From these results the authors estimate the migration energy of vacancies in iron at 1.27 +- 0.09 eV. (Auth.)

  7. Investigation of the chemical effects of nuclear transformations by Moessbauer spectroscopy

    Nagy, G.A.

    1978-01-01

    Moessbauer spectroscopy proved to be a very successful method for the investigation of the effect of nuclear transformations in solid matrixes. This method makes possible the observation of the atoms to be investigated without the dissolution of the sample i.e. without interfering with the eventual intermediates or their environment, ensuring thus ''in situ'' analysis. The method besides the informations concerning the chemical state of the derivative gives data concerning its immediate environment and its site in the crystal lattice. Products having a very short lifetime can be observed, too. Though the method is suitable only for the investigation of such nucleogenetic nuclei which are at the same time also Moessbauer atoms, the method has several times given fundamental information on the chemical and crystal-structural effects of transformations in solid compounds. Isotopes from nuclear reactions are in general pushed back at a high kinetical energy during their formation, and the method makes possible to deduce the consequences of this push-back effect and of radioactive decays and nuclear reactions. A separate chapter summarizes the recent statements concerning the consequences of the electron capture in solid cobalt compounds, the consequences of the isomer transition of Sn-119 in solid tin compounds etc. (P.J.)

  8. Moessbauer spectroscopy of metals from birth to death

    Fujita, Francisco Eiichi [Osaka University (Japan)

    1998-12-15

    In today's metallurgy, precision techniques, such as X-ray and electron diffraction, electron microscopy, infrared spectroscopy and electron probe micro-analyzer, are being indispensably used, and, comparing to them, Moessbauer spectroscopy is not inferior at all in usefulness, convenience and cost benefit. Actually, however, it is not yet popular among the metallurgists probably because people believe that the Moessbauer effect is a difficult physics, radioactive sources are difficult to handle, and spectral analyses are complicated. These beliefs are in fact groundless and must be dissolved for further diffusion of this useful Moessbauer technique in metals and other industries.The present introductory talk intends to help people's better understanding and no anxiety for using the Moessbauer spectroscopy by showing how it can be applied to various problems of metals and alloys from their birth to the end, that is, from the study of minerals and ores before smelting to that of corrosion and other failures.Firstly, the principle of Moessbauer spectroscopy will be explained with simplest illustrations together with simple pictures of apparatuses including the high temperature furnace and the high pressure cell.In the second will be shown typical examples of Moessbauer patterns of magnetite, carbon steel and other alloys, with indications of how to analyze the seemingly complicated spectra. Some other examples will be shown with special apparatuses easy to measure. The usefulness and convenience of Moessbauer spectroscopy will be understood again from these examples. More examples will be on amorphous alloys and other advanced materials.

  9. The effect of decaying atomic states on integral and time differential Moessbauer spectra

    Kankeleit, E.

    1975-01-01

    Moessbauer spectra for time dependent monopole interaction have been calculated for the case that the nuclear transition feeding the Moessbauer state excites an electric state of the atom. This is assumed to decay in a time comparable with the lifetime of the Moessbauer state. Spectra have been calculated for both time differential and integral experiments. (orig.) [de

  10. Moessbauer study of the lattice dynamics of tin atoms in antimony

    Sitek, J.

    1975-01-01

    The Moessbauer effect probability f was investigated for tin impurity atoms in the SnSb solution (the impurity varied from 3 at% to 15 at%). The absolute value of the Moessbauer effect probability was determined from Moessbauer absorption spectra by the area method using a calibration absorber of a β-tin foil with known f. (Z.S.)

  11. OSSM2008 Polish Moessbauer Community Meeting: Program, Abstracts and List of Participants

    2008-01-01

    The Polish Moessbauer Community Meeting - OSSM2008 has been organized by Polish scientists using the Moessbauer spectroscopy in their research. Main subjects of the meeting are investigations of modern materials electronic structure by means of Moessbauer effect (ME), using ME in biological test of tissue diseases and ME investigation of physical properties of different steels

  12. Siting history and current construction status of disposal facility for low and intermediate level radioactive waste in Korea

    Sakai, Akihiro; Kikuchi, Saburo; Maruyama, Masakatsu

    2008-01-01

    Korean government decided disposal site for low and intermediate level radioactive waste (LILW), which is located at coastal area near the Wolsong nuclear power plants in Gyeong-Ju city in December. 2005, based on the result of votes of residents in four candidate sites. Since then, Korea Hydro and Nuclear Power Co., Ltd (KHNP), which is the management company of the LILW disposal facility, has carried out the preparation for construction of disposal facility and its licensing process. At the first phase, 100 thousand drums in 200 liter are planned to be disposed of in the rock cavern type disposal facility located at the depth from 80m to 130m below the sea level, and finally 800 thousand drums in 200 liter are planned to be disposed of in the site. This report shows the history of siting for the LILW disposal, the outline of design of disposal facility and current status of its construction, based on the information which was obtained mainly during our visit to the disposal site in Korea. (author)

  13. A solubility-limited-source-term model for the geological disposal of cemented intermediate-level waste

    Robinson, P.C.; Hodgkinson, D.P.; Tasker, P.W.; Lever, D.A.; Windsor, M.E.; Grime, P.W.; Herbert, A.W.

    1988-01-01

    This paper presents and illustrates the use of a source-team model for an intermediate-level radioactive-waste repository. The model deals with the behaviour of long-lived nuclides after the initial containment period. The major processes occurring in the near-field are included, namely sorption, elemental solubility limits, chain decay and transport due to groundwater flow. The model is applied to a realistic example of ILW disposal. From this it is clear that some nuclides are present in sufficient quantities to reach their solubility limit even when the assumed sorption coefficients are large. For these nuclides the precise sorption coefficient is unimportant. It is also clear that some daughter products, in particular Pb-210, become significant. The toxicity of the repository porewater is calculated and it is shown that, although this toxicity is high compared to levels acceptable in drinking water, it is much lower than the toxicity of the waste itself. However, the near-field chemical environment is only one of a number of containment barriers. In addition, it has been shown that the rate at which radionuclides enter the rock surrounding the repository is very low. (author)

  14. Development of a computer code for low-and intermediate-level radioactive waste disposal safety assessment

    Park, J. W.; Kim, C. L.; Lee, E. Y.; Lee, Y. M.; Kang, C. H.; Zhou, W.; Kozak, M. W.

    2002-01-01

    A safety assessment code, called SAGE (Safety Assessment Groundwater Evaluation), has been developed to describe post-closure radionuclide releases and potential radiological doses for low- and intermediate-level radioactive waste (LILW) disposal in an engineered vault facility in Korea. The conceptual model implemented in the code is focused on the release of radionuclide from a gradually degrading engineered barrier system to an underlying unsaturated zone, thence to a saturated groundwater zone. The radionuclide transport equations are solved by spatially discretizing the disposal system into a series of compartments. Mass transfer between compartments is by diffusion/dispersion and advection. In all compartments, radionuclides are decayed either as a single-member chain or as multi-member chains. The biosphere is represented as a set of steady-state, radionuclide-specific pathway dose conversion factors that are multiplied by the appropriate release rate from the far field for each pathway. The code has the capability to treat input parameters either deterministically or probabilistically. Parameter input is achieved through a user-friendly Graphical User Interface. An application is presented, which is compared against safety assessment results from the other computer codes, to benchmark the reliability of system-level conceptual modeling of the code

  15. Use of the mixture of clay and crushed rock as a backfill material for low and intermediate level radioactive waste repository. Appendix 10: Republic of Korea

    Cho, W.J.; Lee, J.O.; Hahn, P.S.; Chun, K.S.

    2001-01-01

    At the time of the CRP, a repository for low and intermediate level radioactive wastes arising from nuclear power plant operation and radioisotope application in the Republic of Korea was to be constructed in the bedrock below ground surface. As the intermediate level waste cavern would contain the major part of radionuclide inventory in the cavern, the radionuclide release from the intermediate level waste cavern was therefore important from the viewpoint of disposal facility performance. The then current design concept suggested that the intermediate level waste would be emplaced into the compartment made of reinforced concrete, and the space between the concrete wall and cavern surface would be backfilled with a clay-based material. As compacted clay-based materials have a low hydraulic conductivity and the hydraulic gradient in a disposal cavern was expected to be relatively low, molecular diffusion was considered to be the principal mechanism by which radionuclides would migrate through the backfill. The mixture of calcium bentonite and crushed rock was being suggested as a candidate backfill material. This appendix summarises the KAERI research activities on the evaluation of hydraulic conductivity, radionuclide diffusion coefficient, and mechanical properties of the candidate clay-based backfill material for the intermediate level waste cavern

  16. Intermediate treatments

    John R. Jones; Wayne D. Shepperd

    1985-01-01

    Intermediate treatments are those applied after a new stand is successfully established and before the final harvest. These include not only intermediate cuttings - primarily thinning - but also fertilization, irrigation, and protection of the stand from damaging agents.

  17. Moessbauer effect in lattice dynamics. Experimental techniques and applications

    Chen, Yi-Long; Yang, De-Ping

    2007-01-01

    This up-to-date review closes an important gap in the existing literature by providing a comprehensive description of the applications of Moessbauer effect in lattice dynamics, along with a collection of applications in metals, alloys, amorphous solids, molecular crystals, thin films, and nanocrystals. It is the first book to systematically compare Moessbauer spectroscopy using synchrotron radiation to conventional Moessbauer spectroscopy, discussing in detail its advantages and capabilities, backed by the latest theoretical developments and experimental examples. Intended as a self-contained volume that may be used as a complete reference or textbook, 'Moessbauer Effect in Lattice Dynamics' adopts new pedagogical approaches with several non-traditional and refreshing theoretical expositions, while all quantitative relations are derived with the necessary details so as to be easily followed by the reader. Two entire chapters are devoted to the study of the dynamics of impurity atoms in solids, while a thorough description of the Mannheim model as a theoretical method is presented and its predictions compared to experimental results. Finally, an in-depth analysis of absorption of Moessbauer radiation is presented, based on recent research by one of the authors, resulting in an exact expression of fractional absorption and a method to determine the optimal thickness of an absorber. Supplemented by elaborate appendices containing constants and parameters. (orig.)

  18. Inelastic scattering in condensed matter with high intensity Moessbauer radiation

    Yelon, W.B.; Schupp, G.

    1993-02-01

    The QUEGS facility at MURR has produced a number of new results and demonstrated the range of potential applications of high resolution, high intensity Moessbauer scattering. This work has been carried out by both MU and Purdue researchers and includes published results on Na, W, pentadecane, polydimethylsiloxane and other systems, manuscripts submitted on alkali halides (Phys. Rev. B) and accurate Moessbauer lineshape measurements (Phys. Rev. C), and manuscripts in preparation on glycerol, NiAl and Moessbauer spectra obtained by modulating a scattering crystal. Recently, new collaborations have been initiated which will substantially enhance our efforts. These are with W. Steiner (Vienna), G. Coddens (Saclay), and R. D. Taylor (Los Alamos). Steiner is experienced with Fe-57 Moessbauer scattering, while Coddens specializes in quasielastic neutron scattering; both of these areas naturally complement our work. R. D. Taylor has pioneered Moessbauer spectroscopy from the time of its discovery and has already made important contributions to our study of lattice dynamics and superconductivity for lead alloyed with small quantities of tin. At the same time, a significant instrument upgrade is underway, funded in part by the DOE-URIP program

  19. Prediction of radionuclide invention for low-and intermediate-level radioactive waste by considering concentration limit of waste package

    Jung, Kang Il; Kim, Min Seong; Jeong, Noh Gyeon; Park, Jin Beak [Korea Radioactive Waste Agency(KORAD), Daejeon (Korea, Republic of)

    2017-03-15

    The result of a preliminary safety assessment that was completed by applying the radionuclide inventory calculated on the basis of available data from radioactive waste generation agencies suggested that many difficulties are to be expected with regard to disposal safety and operation. Based on the results of the preliminary safety assessment of the entire disposal system, in this paper, a unit package exceeding the safety goal is selected that occupies a large proportion of radionuclides in intermediate-level radioactive waste. We introduce restrictions on the amount of radioactivity in a way that excludes the high surface dose rate of the package. The radioactivity limit for disposal will be used as the baseline data for establishing the acceptance criteria and the disposal criteria for each disposal facility to meet the safety standards. It is necessary to draw up a comprehensive safety development plan for the Gyeongju waste disposal facility that will contribute to the construction of a Safety Case for the safety optimization of radioactive waste disposal facilities.

  20. Elaboration of a questionnaire for establishment of the Brazilian inventory of low and intermediate level radioactive waste

    Calabria, Jaqueline A.A.; Silva, Fabio; Taddei, Maria Helena T.

    2013-01-01

    Since 2008, Brazilian Commission for Nuclear Energy, CNEN, has been working in the Project of Repository for Low and Intermediate Level Radioactive Wastes, (RBMN Project) and the Centre for Development of Nuclear Technology (CDTN) is responsible for the technical coordination of this project. Among activities under development, the survey of National radwaste inventory must be firstly concluded since it is a requirement for the project cost estimation. Hence, an electronic questionnaire was created to collect all information necessary to obtain the volume of the treated and non-treated waste, presently stored in Brazil. This questionnaire was elaborated after survey of the possible characteristics of radioactive waste generated in nuclear and radioactive facilities and it will be available online only for registered users. The information gathered with this questionnaire was related only with the amount of radioactive waste and some generic characteristics, the isotopic inventory will be performed in future. The objective of this work is to present this form and its creation process. (author)

  1. OPG's long term management proposal for low and intermediate level radioactive waste: project description, operations

    Witzke, P.

    2011-01-01

    Although the Deep Geologic Repository (DGR) is approximately 8 years away from being placed into service, it is time to start planning for operations. Ontario Power Generation's (OPG) Nuclear Waste Management Division (NWMD) has a systematic approach to preparing for operation of any new facility that is readily applicable to the DGR. The DGR Operational Readiness Plan has been benchmarked at similar facilities in North America and Europe. The operating vision is a living model, and is constantly being reviewed and refined to align with the detailed design of the DGR as it proceeds through its phases of development. Combined with 40 years of operating surface storage facilities for the storage of Low and Intermediate Level Waste (LILW), the DGR operating vision will enable NWMD to provide meaningful input during COMS (Constructability, Operability, Maintainability, and Safety) review in the DGR project detailed-design phase in 2011/2012. A Work Breakdown Structure has been used to communicate the detail of the operating vision, and also to estimate the costs of Operational Readiness and Operations during the lifetime of the facility. (author)

  2. Concept and Idea-Project for Yugoslav Low and Intermediate level Radioactive Waste Materials Final Disposal Facility

    Peric, A.

    1997-01-01

    Encapsulation of rad waste in a mortar matrix and displacement of such solidified waste forms into the shallow land burial system, engineered trench system type is suggested concept for the final disposal of low and intermediate level rad waste. The mortar-rad waste mixtures are cured in containers of either concrete or metal for an appropriate period of time, after which solidified rad waste-mortar monoliths are then placed in the engineered trench system, parallelepiped honeycomb structure. Trench consists of vertical barrier-walls, bottom barrier-floors, surface barrier-caps and permeable-reactive walls. Surroundings of the trench consists of buffer barrier materials, mainly clay. Each segment of the trench is equipped with the independent drainage system, as a part of the main drainage. Encapsulation of each filled trench honeycomb segment is performed with concrete cap. Completed trench is covered with impermeable plastic foil and soil leaner, preferably clay. Paper presents an overview of the final disposal facility engineered trench system type. Advantages in comparison with other types of final disposal system are given. (author)

  3. A Python Implementation of an Intermediate-Level Tropical Circulation Model and Implications for How Modeling Science is Done

    Lin, J. W. B.

    2015-12-01

    Historically, climate models have been developed incrementally and in compiled languages like Fortran. While the use of legacy compiledlanguages results in fast, time-tested code, the resulting model is limited in its modularity and cannot take advantage of functionalityavailable with modern computer languages. Here we describe an effort at using the open-source, object-oriented language Pythonto create more flexible climate models: the package qtcm, a Python implementation of the intermediate-level Neelin-Zeng Quasi-Equilibrium Tropical Circulation model (QTCM1) of the atmosphere. The qtcm package retains the core numerics of QTCM1, written in Fortran, to optimize model performance but uses Python structures and utilities to wrap the QTCM1 Fortran routines and manage model execution. The resulting "mixed language" modeling package allows order and choice of subroutine execution to be altered at run time, and model analysis and visualization to be integrated in interactively with model execution at run time. This flexibility facilitates more complex scientific analysis using less complex code than would be possible using traditional languages alone and provides tools to transform the traditional "formulate hypothesis → write and test code → run model → analyze results" sequence into a feedback loop that can be executed automatically by the computer.

  4. Monitoring Programme of Radionuclide Migration Through Food Chains at Low and Intermediate Level Radioactive Waste Repository in Trgoska Gora Mountain

    Schaller, A.; Lokner, V.; Kucar Dragicevic, S.; Subasic, D.; Barisic, D.

    2001-01-01

    Full text: Basic objective of the paper is to prepare a comprehensive programme of monitoring at the preferred site for low and intermediate level radioactive waste repository in the region of Trgovska Gora mountain. The programme is based on available information regarding hydrogeology, lithostratigraphy, tectonics, seismotectonics, geomorphology, meteorology, bioecology, demography and other site relevant disciplines. It is supposed to ensure (1) identification of the zero state at the broader region of the Trgovska gora mountain, and (2) to underline activities needed for monitoring of concentrations of expected radionuclides throughout possible pathways (particularly through food chains) that would migrate to the biosphere in the period after start of radioactive waste repository operation. Inventory of radionuclides contained in the radioactive waste to be disposed of at the site is naturally an important element of the programme structure. There should be identified those radionuclides which concentrations require to be monitored. Concentration measuring methods are proposed in the article. In addition, relevant aquatic and terrestrial organisms, serving as bioindicators, are identified. Types, quantities, frequency and methodology of sampling present an important part of the monitoring programme. Determination of monitoring sites for undertaking particular types of sampling (e.g. stream waters, stream sediment, detritus, ichtiofauna, groundwater, terrestrial organisms, honey, etc.), presenting an important aspect of a well-organised monitoring programme, is also included into this presentation. (author)

  5. Risk management in the project of implantation of the repository for low and intermediate level radioactive waste

    Borssatto, Maria de Fatima B.; Tello, Cledola Cassia O. de; Uemura, George

    2011-01-01

    Project RBMN is part of the Brazilian solution for the storage of radioactive waste generated by the activities of nuclear energy in Brazil. The aim of RBMN is to implement the National Repository to dispose the low and intermediate-level radioactive waste. Risk is a characteristic of all projects, and it is originated from uncertainties, assumptions and the environment of execution of the project. Risk management is the way to monitor systematically these uncertainties and a guaranty that the goals of the project will be attained. A specific methodology for the risk management of the Project RBMN is under development, which integrates models and processes for identification and analysis of risks, reactions, monitoring, control and planning of risk management. This methodology is fundamental and will be of primordial importance for future generations who will be responsible for the operation at final stages, closure and institutional control during the post-closure of the repository. It will provide greater safety to executed processes and safeguarding risks and specific solutions for this enterprise, guaranteeing the safety of the repository in its life cycle, which has a foreseen duration of at least three hundred years. The aim of this paper is to present the preliminary analysis of the opportunities, threats, strong points and weak points identified up to now, that will provide support to implement risk management procedures. The methodology will be based on the PMBOK R - Project Management Board of Knowledge - and will take into consideration the best practices for project management.(author)

  6. Elaboration of a questionnaire for establishment of the Brazilian inventory of low and intermediate level radioactive waste

    Calabria, Jaqueline A.A.; Silva, Fabio, E-mail: jaalmeida@cdtn.br, E-mail: silvaf@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Taddei, Maria Helena T., E-mail: mhtaddei@cnen.gov.br [Comissao Nacional de Energia Nuclear (LAPOC/CNEN), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas; Marumo, Julio T., E-mail: jtmarumo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Since 2008, Brazilian Commission for Nuclear Energy, CNEN, has been working in the Project of Repository for Low and Intermediate Level Radioactive Wastes, (RBMN Project) and the Centre for Development of Nuclear Technology (CDTN) is responsible for the technical coordination of this project. Among activities under development, the survey of National radwaste inventory must be firstly concluded since it is a requirement for the project cost estimation. Hence, an electronic questionnaire was created to collect all information necessary to obtain the volume of the treated and non-treated waste, presently stored in Brazil. This questionnaire was elaborated after survey of the possible characteristics of radioactive waste generated in nuclear and radioactive facilities and it will be available online only for registered users. The information gathered with this questionnaire was related only with the amount of radioactive waste and some generic characteristics, the isotopic inventory will be performed in future. The objective of this work is to present this form and its creation process. (author)

  7. Development of low-pH cements for immobilisation of intermediate level radioactive waste: achievements and challenges

    Martins de Freitas, Regeane; Al-Tabbaa, Abir [Engineering Department, University of Cambridge, Cambridge (United Kingdom)

    2013-07-01

    Although cementation is a widely recognized solidification/ stabilization process for immobilisation of Intermediate Level Radioactive Waste (ILRW), the low resistance to hyper-alkaline pore waters compromises the effectiveness of the process when Portland Cement (PC) is employed. Moreover the manufacture of PC is responsible for significant CO{sub 2} emissions. In this context, low pH cements are environmentally more suitable and have emerged as a potential alternative for obtaining secure waste forms. This paper summarises the achievements on development of low-pH cements and the challenges of using these new materials for the ILRW immobilisation. The performance of waste forms is also discussed in terms of radionuclides release. Reactive magnesium oxide and magnesium phosphate cements are emphasised as they feature important advantages such as consumption of available constituents for controlling acid-base reactions, reduced permeability and higher density. Additionally, in order to identify new opportunities for study, the long-term modelling approach is also briefly discussed. (authors)

  8. Community dynamics in the siting process for a low to intermediate level nuclear waste facility in Kincardine, Ontario

    Al-Haydari, D.

    2007-01-01

    The use of nuclear technology to generate electricity inevitably produces waste that is detrimental to the environment and human health. Finding communities that will accept nuclear waste disposal facilities is extremely challenging. Furthermore, the siting of a nuclear waste disposal facility is more than a technological analysis, but a matter that includes a variety of social, ethical and political considerations. This study is aimed to assess the role of the place-based community, communities of interest and communities of identity involved in the voluntary siting process for a low to intermediate level nuclear waste disposal facility in Ontario. To accomplish this, a framework was developed and applied though a case study evaluation of the siting process for the Deep Geologic Repository in Kincardine, Ontario. The framework highlights four key procedural principles that were used to analyze the siting process: trust, public participation, equity and risk. The data revealed that the positions of the communities involved in the siting process varied depending on the meaningful fulfillment the four key procedural principles. (author)

  9. Experiments relating to hydrogen generated by corrosion processes associated with repositories for intermediate-level radioactive wastes

    Schenk, R.

    1983-12-01

    Organic components in an intermediate level waste repository decompose under both aerobic and anaerobic conditions to produce carbon dioxide, which may lead to acid corrosion of metallic containers and hence to hydrogen production. The possibility of hydrogen production within the repository must be considered in determining the long term safety. Thermodynamic calculations show that only pure water is required to produce hydrogen with iron in a repository. The hydrogen evolution rate is thus the important parameter. However, the available kinetic data is insufficient and needs to be supplemented experimentally. Carbon steel specimens were immersed in water over which several gas mixtures containing nitrogen, oxygen and carbon dioxide were passed; the amount of hydrogen picked up by the gas stream was measured. 1.4 - 28 ml hydrogen per square meter per hour was evolved when the gas mixture contained 1 and 20 volume per cent carbon dioxide respectively. Hydrogen was also detected in natural CO 2 -free water when oxygen concentration cells are present. No hydrogen could be detected at pH 8.5 and above. The experiments were all carried out at 25 degrees C and atmospheric pressure and restricted to the carbonate system. Natural waters contain a mixture of salts; this may increase or reduce the hydrogen evolution rate. Higher temperatures and pressures, in particular a higher partial pressure of carbon dioxide, will probably lead to an increase in the hydrogen evolution rate. (author)

  10. OPG's deep geologic repository for low and intermediate level waste - public participation and aboriginal engagement

    Wilson, M.

    2011-01-01

    Ontario Power Generation (OPG)'s Public Participation and Aboriginal Engagement Program for the proposed Deep Geologic Repository (DGR) for low and intermediate level waste (L and ILW) began with the signing of a Memorandum of Understanding (MOU) in 2002 between OPG and the Municipality of Kincardine. The MOU set out the terms under which the two parties would jointly study the feasibility of different options for the long-term management of L and ILW at the Bruce nuclear site. A consultant, independent from both the Municipality of Kincardine and OPG, was retained to manage the assessment of options as well as a communication plan to ensure the public and Aboriginal peoples were kept apprised of all activities associated with the MOU. This early commitment to transparency and openness, with its ensuing opportunities for the public and Aboriginal peoples to become informed, ask questions, and engage in meaningful two-way dialogue about the early assessment of options, established the foundation and later became the hallmark of the DGR Project's Public Participation and Aboriginal Engagement program. This paper provides an overview of the development, nature and results of that program as it has evolved through the early investigative stages of options and through the environmental assessment and licencing process for the proposed DGR Project. (author)

  11. The OPG/Kincardine hosting agreement for a deep geologic repository for OPG's low- and intermediate-level waste

    Castellan, A.G.; Barker, D.E.

    2006-01-01

    A Hosting Agreement has been reached between Ontario Power Generation and the Municipality of Kincardine for the purpose of siting a long-term management facility for low- and intermediate-level radioactive waste at the Western Waste Management Facility. Following an independent review of the feasibility of three options for a long-term facility at the site, including a review of the safety, geotechnical feasibility, social and economic effects and potential environmental effects, Kincardine passed a resolution indicating their preference for a Deep Geologic Repository. A Host Community Agreement has been negotiated based on this preference, and on information that had been gathered from municipal authorities at other locations that have hosted similar facilities. The Hosting Agreement includes financial compensation, totalling $35.7 million (Canadian 2004) to the Municipality of Kincardine and to four surrounding municipalities. The financial aspects include lump sum payments based on achieving specific project milestones as well as annual payments to each of the municipalities. The payments are indexed to inflation, and are also contingent on the municipalities acting reasonably and in good faith during the licencing process of the proposed facility. In addition to the fees, the Agreement includes provision for a Property Value Protection Plan that would provide residents with compensation in the event that there is depreciation in property value shown to directly result from a release from the proposed facility. New permanent OPG jobs supporting the project would be located at the site. OPG and Kincardine will support a centre of nuclear excellence. (author)

  12. Applying multi-criteria analysis to radiation protection optimisation of low and intermediate level radioactive waste disposal

    Pages, P.; Schneider, T.; Lombard, J.

    1991-01-01

    Introduction of ALARA principles in the field of radioactive waste management implies a definition of the main characteristics of the decisional framework. Specific aspects should be taken into account: long term effects, large uncertainties and/or probabilistic events, with particular attention to the public and the political authorities. Traditional cost-benefit analysis is not qualified to deal with these different dimensions of the risk. The aim of this paper is to describe the principles of multi-criteria analysis applied to low and intermediate level radioactive waste disposal. Three categories of barriers can be distinguished acting at different protection levels: site characteristics, waste package and disposal system. A set of possible solutions can be identified, but the selection of the 'optimum' is not easy because of the diversity of the factors to be allowed for. For example, the following problem needs to be addressed: is it preferable to limit public radiation exposure several hundred years ahead or to reduce occupational exposure during the monitoring period of the disposal facility? An optimisation study is currently being performed on the various components of the structure, assuming given site and waste package characteristics. Four steps are distinguished: identification and analysis of options for the structure; selection and estimation of the qualitative and quantitative criteria; determination of the 'most interesting' solutions using multi-criteria analysis; sensitivity analysis and discussion on uncertainties related to the various assumptions. Based on the preliminary findings, the paper focuses on practical solutions to address the methodological issues raised in applying the optimisation procedures to radioactive waste management. (au)

  13. Maximum flood hazard assessment for OPG's deep geologic repository for low and intermediate level waste

    Nimmrichter, P.; McClintock, J.; Peng, J.; Leung, H.

    2011-01-01

    Ontario Power Generation (OPG) has entered a process to seek Environmental Assessment and licensing approvals to construct a Deep Geologic Repository (DGR) for Low and Intermediate Level Radioactive Waste (L&ILW) near the existing Western Waste Management Facility (WWMF) at the Bruce nuclear site in the Municipality of Kincardine, Ontario. In support of the design of the proposed DGR project, maximum flood stages were estimated for potential flood hazard risks associated with coastal, riverine and direct precipitation flooding. The estimation of lake/coastal flooding for the Bruce nuclear site considered potential extreme water levels in Lake Huron, storm surge and seiche, wind waves, and tsunamis. The riverine flood hazard assessment considered the Probable Maximum Flood (PMF) within the local watersheds, and within local drainage areas that will be directly impacted by the site development. A series of hydraulic models were developed, based on DGR project site grading and ditching, to assess the impact of a Probable Maximum Precipitation (PMP) occurring directly at the DGR site. Overall, this flood assessment concluded there is no potential for lake or riverine based flooding and the DGR area is not affected by tsunamis. However, it was also concluded from the results of this analysis that the PMF in proximity to the critical DGR operational areas and infrastructure would be higher than the proposed elevation of the entrance to the underground works. This paper provides an overview of the assessment of potential flood hazard risks associated with coastal, riverine and direct precipitation flooding that was completed for the DGR development. (author)

  14. High pressure Moessbauer spectroscopy of perovskite iron oxide

    Nasu, S; Morimoto, S; Kawakami, T; Kuzushita, K; Takano, M

    2003-01-01

    High-pressure sup 5 sup 7 Fe Moessbauer spectroscopy using a diamond anvil cell has been performed for perovskite iron oxides SrFeO sub 3 , CaFeO sub 3 and La sub 1 sub / sub 3 Sr sub 2 sub / sub 3 O sub 3. The charge states and the magnetic dependency to pressure were determined. Pressure magnetic phase diagrams of these perovskite iron oxides are determined up to about 70 GPa. To be clear the magnetic ordered state, they are measured up to 7.8 T external magnetic fields at 4.5K. The phase transition of these perovskite oxides to ferromagnetisms with high magnetic ordered temperature is observed. In higher pressure, high spin-low spin transition of oxides besides CaFeO sub 3 is generated. The feature of Moessbauer spectroscopy, perovskite iron oxide and Moessbauer spectroscopy under high pressure are explained. (S.Y.)

  15. Molecular Sensors for Moisture Detection by Moessbauer Spectroscopy

    Renz, F.; Souza, P. A. de; Klingelhoefer, G.; Goodwin, H. A.

    2002-01-01

    A parameter of importance in various industrial and commercial applications is sensitivity to moisture. A new class of molecular sensors which enable the qualitative and quantitative determination of air moisture (high selectivity and sensitivity) by application of Moessbauer spectroscopy as the probe technique has been investigated. The electronic properties of the iron-containing sensor depend upon the presence of moisture which is taken up by it and this process is accompanied by a change in electronic spin ground state which can be detected by Moessbauer spectroscopy. The sensor is suitable for in-field and industrial application using the recently developed Moessbauer spectrometer MIMOS II. Possible suitability for the detection of moisture in extraterrestrial environments is considered.

  16. Low temperature {sup 57}Fe Moessbauer study of cucumber root

    Kovacs, K; Kuzmann, E; Homonnay, Z; Vertes, A [Institute of Chemistry, Eoetvoes Lorand University, PO Box 32, 1512 Budapest (Hungary); Fodor, F [Department of Plant Physiology and Molecular Plant Biology, Eoetvoes Lorand University, PO Box 32, 1512 Budapest (Hungary); Machala, L, E-mail: kkriszti@chem.elte.h [Centre for Nanomaterial Research, Palacky University, Svobody 26, Olomouc 771 46 (Czech Republic)

    2010-03-01

    Iron uptake and distribution in cucumber root were studied with the help of {sup 57}Fe Moessbauer spectroscopy at low temperature applying external magnetic field. Cucumber was grown in iron sufficient modified Hoagland nutrient solution. Moessbauer spectra of the frozen roots taken at 4.2 and 1.5 K, at 5 T external magnetic field support the identification of the main iron species (Fe{sup III}-carboxylates, hydrous ferric oxides, Fe{sup III}-sulfate-hydroxide) suggested according to its Moessbauer spectra taken between 35-200 K [1]. The magnetic ordering temperature of the hydrous ferric oxide and Fe{sup III}-sulfate-hydroxide was found to be in the range of 4.2-1.5 K, which suggests the incorporation of H{sub 3}O{sup +}, PO{sub 4}{sup 3-} and citrate into these minerals.

  17. Dedicated detectors for surface studies by Moessbauer spectroscopy

    Bibicu, I.; Rogalski, M.S.; Nicolescu, G.

    2001-01-01

    Moessbauer spectroscopy is a nuclear resonance method largely utilized in solid state studies. Following resonant nuclear absorption, gamma radiations, conversion X-rays, conversion or Auger electrons are emitted. By detection of gamma radiations information about the sample as a whole are obtained while by detection of electrons or X radiation one obtains data on the surface layer. Our laboratory was among the firsts to produce and use flow gas proportional detectors for surface studies by Moessbauer spectroscopy. Four types of detectors were devised: - detectors for electron detection (90% He + 10% CH 4 ); - detectors for conversion X-ray detection (90% Ar + 10% CH 4 ); - detectors for electrons or internal conversion X rays; - detectors for simultaneous detection of electrons and conversion X rays emitted from the same source. All detectors allow simultaneous Moessbauer measurements both for surface and volume for a given sample. Details of construction are presented for the four types of detectors

  18. Moessbauer sum rules for use with synchrotron sources

    Lipkin, H.J.

    1995-01-01

    The availability of tunable synchrotron radiation sources with millivolt resolution has opened prospects for exploring dynamics of complex systems with Moessbauer spectroscopy. Early Moessbauer treatments and moment sum rules are extended to treat inelastic excitations measured in synchrotron experiments, with emphasis on the unique conditions absent in neutron scattering and arising in resonance scattering: prompt absorption, delayed emission, recoilfree transitions, and coherent forward scattering. The first moment sum rule normalizes the inelastic spectrum. Sum rules obtained for higher moments include the third moment proportional to the second derivative of the potential acting on the Moessbauer nucleus and independent of temperature in the harmonic approximation. Interesting information may be obtained on the behavior of the potential acting on this nucleus in samples not easily investigated with neutron scattering, e.g., small samples, thin films, time-dependent structures, and amorphous-metallic high pressure phases

  19. Moessbauer Study of Iron-Containing Carbon Nanotubes

    Marco, J. F.; Gancedo, J. R. [CSIC, Instituto de Quimica-Fisica ' Rocasolano' (Spain); Hernando, A.; Crespo, P.; Prados, C.; Gonzalez, J. M. [Instituto de Magnetismo Aplicado (Spain); Grobert, N.; Terrones, M.; Walton, D. R. M.; Kroto, H. W. [University of Sussex, Fullerene Science Centre, School of Chemistry, Physics and Environmental Science (United Kingdom)

    2002-03-15

    {sup 57}Fe transmission Moessbauer at temperatures between 18 and 298 K and magnetic measurements have been used to characterize Fe-filled carbon nanotubes which were prepared by pyrolisis of Ferrocene + C{sub 60} at atmospheric pressure under an Ar atmosphere at 1050{sup o}C. The Moessbauer data have shown that the Fe phases encapsulated within the carbon nanotubes are {alpha}-Fe, Fe{sub 3}C and {gamma}-Fe. The magnetic results are compatible with the Moessbauer data. Taken together the results allow us to propose a simple picture of the distribution of iron phases within the carbon nanotubes which would consist of an {alpha}-Fe core surrounded by an {gamma}-Fe shell, finally covered by an Fe{sub 3}C layer.

  20. Iron chelates: a challenge to chemists and Moessbauer spectroscopists

    Homonnay, Z., E-mail: homonnay@chem.elte.hu; Szilagyi, P. A.; Vertes, A. [Eoetvoes Lorand University, Laboratory of Nuclear Chemistry, Institute of Chemistry (Hungary); Kuzmann, E. [Hungarian Academy of Sciences, Department of Nuclear Chemistry, Chemical Research Center (Hungary); Sharma, V. K. [Florida Institute of Technology (United States); Molnar, G.; Bousseksou, A. [CNRS UPR-8241, Laboratoire de Chimie de Coordination (France); Greneche, J.-M. [Universite du Maine, Laboratoire de Physique de l' Etat Condense, CNRS UMR 6087 (France); Brausam, A.; Meier, R.; Eldik, R. van [University of Erlangen-Nuernberg, Institute for Inorganic Chemistry (Germany)

    2008-02-15

    The speciation of iron in aqueous solutions containing Fe{sup 3+} and selected chelates such as EDTA, EDDA, CDTA and HEDTA has been studied using transmission {sup 57}Fe Moessbauer spectrometry in frozen solutions. The protonation of various complexes as well as binuclear complex formation could be detected as a function of pH. Autoreduction of Fe{sup 3+} to Fe{sup 2+} was observed in several cases. Reaction with hydrogen peroxide proved to be rather different for the four ligands, while the dihapto complex [XFe({eta}{sup 2}-O{sub 2})]{sup 3-} had surprisingly identical Moessbauer parameters for X = EDTA, CDTA or HEDTA. Paramagnetic spin relaxation observed in the Moessbauer spectra was found to be strongly influenced by the identity of the chelating ligand, despite the basically spin-spin origin of the phenomenon.

  1. Moessbauer study of phase transitions under high hydrostatic pressures. 1

    Kapitanov, E.V.; Yakovlev, E.N.

    1979-01-01

    Experimental results of the hydrostatic pressure influence on Moessbauer spectrum parameters are obtained over the pressure range including the area of structural phase transition. A linear increase of the Moessbauer effect probability (recoilless fraction) is accompanied by a linear decrease of the electron density at tin nuclei within the pressure range foregoing the phase transition. The electric resistance and the recoilless fraction of the new phase of Mg 2 Sn are lower, but the electron density at tin nuclei is greater than the initial phase ones. Hydrostatic conditions allow to fix clearly the diphasic transition area and to determine the influence of the pressure on the Moessbauer line position and on the recoilless fraction of the high pressure phase. The phase transition heat Q = 415 cal mol -1 is calculated using recoilless fractions of the high and low pressure phases at 25 kbar. The present results are qualitatively and quantitatively different from the results, obtained at nonhydrostatic conditions. (author)

  2. High pressure Moessbauer spectroscopy of perovskite iron oxide

    Nasu, Saburo; Suenaga, Tomoya; Morimoto, Shotaro; Kawakami, Takateru; Kuzushita, Kaori; Takano, Mikio

    2003-01-01

    High-pressure 57 Fe Moessbauer spectroscopy using a diamond anvil cell has been performed for perovskite iron oxides SrFeO 3 , CaFeO 3 and La 1/3 Sr 2/3 O 3 . The charge states and the magnetic dependency to pressure were determined. Pressure magnetic phase diagrams of these perovskite iron oxides are determined up to about 70 GPa. To be clear the magnetic ordered state, they are measured up to 7.8 T external magnetic fields at 4.5K. The phase transition of these perovskite oxides to ferromagnetisms with high magnetic ordered temperature is observed. In higher pressure, high spin-low spin transition of oxides besides CaFeO 3 is generated. The feature of Moessbauer spectroscopy, perovskite iron oxide and Moessbauer spectroscopy under high pressure are explained. (S.Y.)

  3. Moessbauer study of Fe-Co nanowires

    Chen Ziyu [Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou (China)]. E-mail: chenzy@lzu.edu.cn; Zhan Qingfeng; Xue Desheng; Li Fashen [Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou (China); Zhou Xuezhi; Kunkel, Henry; Williams, Gwyn [Department of Physics and Astronomy, the University of Manitoba (Canada)

    2002-01-28

    Arrays of Fe{sub 1-x}Co{sub x} (0.0{<=}x{<=}0.92) nanowires have been prepared by an electrochemical process, co-depositing Fe and Co atoms into the pores of anodic aluminium; their compositions were determined by atomic absorption spectroscopy. Transmission electron microscope results show that the nanowires are regularly spaced and uniform in shape with lengths of about 7.5 {mu}m and diameters of 20 nm. The x-ray diffraction indicates a texture in the deposited nanowires. For the composition below 82 at.% cobalt, the nanowires had a body-centred-cubic structure with a [110] preferred orientation. For the 92 at.% cobalt sample, the alloy exhibited a mixture of bcc and face-centred-cubic structure. The room temperature {sup 57}Fe Moessbauer spectra of the arrays of Fe{sub 1-x}Co{sub x} nanowires have second and fifth absorption lines of the six-line pattern with almost zero intensity, indicating that the internal magnetic field in the nanowires lies along the long axis of the nanowire. The maximum values of the hyperfine field (B{sub hf} 36.6{+-}0.1 T) and isomer shift (IS=0.06{+-}0.01 mm s-1) occur for 44 at.% cobalt. The variations of the isomer shift and the linewidths with composition indicate that the Fe{sub 1-x}Co{sub x} alloy nanowires around the equiatomic composition are in an atomistic disordered state. (author)

  4. Moessbauer spectroscopy of the Soledade meteorite

    Paduani, Clederson; Peres, Carlos Ariel Samudio

    2004-01-01

    Full text: Since the early studies of the microstructure and chemical composition of meteorites the formation of magnetic phases have attracted the attention of metallurgists. Mostly metallic specimens presented high contents of nickel and iron as major constituents, and thus the Fe-Ni alloys formed under such special conditions have been the subject of several investigations with a variety of experimental techniques. This is not an easy task considering the weathering process and the distribution of oxides in the metallic matrix, which in some cases varies in composition from one region to another. In this work we applied the Moessbauer spectroscopy to study the iron-bearing phases detected in the meteorite called Soledade. Although no one knows precisely who and when this specimen was found, it received the name of the locality from where it proceeded near the city of Passo Fundo in the state of Rio Grande do Sul in Brazil. The first studies indicate that this metallic meteorite is an octahedrite, with polycrystalline troilite, cohenite, schreibersite and rhabdites as major constituents. It consists of a solid block weighing 68 kg, with an irregular form measuring about 36x22x16 cm. (author)

  5. Distribution of iron cations in natural chromites at different stages of oxidation: a {sup 57}Fe Moessbauer investigation

    Pal, Tapan; Mitra, Sachinath [Jadavpur Univ., Calcutta (India). Dept. of Geological Sciences; Moon, Hi-Soo [Yonsei Univ., Seoul (Korea, Republic of). Dept. of Geology

    1994-07-01

    {sup 57}Fe Moessbauer spectroscopic investigation of natural chromites from two chromite deposits of India (Sukinda and Byrapur) documents partly inverse spinel structure arising out of oxidation. The spectral fitting was based on allowing a disordering distribution of Fe{sup 2+} and Fe{sup 3+} ions at tetrahedral (A) and octahedral (B) sites. Moessbauer investigation of the samples taken from the physico-chemically distinct two horizons of Sukinda viz. brown ore and grey ores, and Byrapur area revealed three types of iron ion distribution as: Fe{sup 2+}(A), Fe{sup 3+}(A) and Fe{sup 2+}(B) (GC-group); (b)Fe{sup 3+}(A{sub 1}), Fe{sup 3+}(A{sub 2}) and Fe{sup 2+}(B) (BC-2 group), and (c) Fe{sup 3+}(A{sub 1}), Fe{sup 3+}(B) (BC-1 group). The distribution pattern of iron cations at A and B sites was linked to the degree of oxidation. These stages of oxidation could be modelled from normal to inverse form. A model suggesting `electron localisation` at the B-sites makes the intermediate stage. Iron site occupancy determined by Moessbauer spectroscopy of the presently studied samples indicates that these fall under three groups of oxidation stages. An early stage of oxidation is shown by samples of group GC, intermediate stage by group BC-2 and final stage by BC-1 group of chromite samples. The imprint of progressive oxidation manifested by Fe cation site occupancy has been correlated with the Fe{sup 2+}/{Sigma}Fe ratios, obtained for each group of samples. (author). 39 refs., 2 figs., 3 tabs.

  6. Moessbauer study of tetramethylene bridged ferrocene derivatives Pt. 2

    Nagy, A.G.; Hillman, M.

    1978-01-01

    Suppositions for the molecular structure of trimethylene bridged ferrocene derivatives, i.e. for the tilt of cyclopentadienyl-rings and shortening of iron-ring distance, were supported by Moessbauer spectroscopic studies. The Moessbauer spectra of 1,1'-tetramethyleneferrocene and 1,1',3,3'-bis(tetramethylene)ferrocene were recorded by means of a constant acceleration type spectrometer using a 57 Co source in a chromium matrix. Simultaneous X-ray analysis of 1,1',3,3'-bis(trimethylene)ferrocene and 1,1',2,2',4,4'-tris(trimethylene)ferrocene confirmed the suppositions. (D.P.)

  7. Moessbauer effect and electron paramagnetic resonance studies on yeast aconitase

    Suzuki, Takashi; Maeda, Yutaka; Sakai, Hiroshi; Fujimoto, Shigeru; Morita, Yuhei.

    1975-01-01

    The Moessbauer effect and electron paramagnetic resonance (EPR) of yeast aconitase [EC 4.2.1.3] purified from the cells of Candida lipolytica (ATCC 20114) were measured. Moessbauer spectra suggested that yeast acontitase mostly contained two high-spin Fe(III) ions in an antiferromagnetically coupled binuclear complex that resembled oxidized 2 Fe ferredoxins, together with a small amount of high-spin Fe(II). EPR spectra recorded no signal at 77 0 K, but showed a slightly asymmetric signal centered at g=2.0 at 4.2 0 K, presumably due to the small amount of Fe(II) Fe(III) pairs. (auth.)

  8. Moessbauer spectroscopic characterization of macromolecule-metallochlorophyll complexes

    Inoue, H.; Fukuda, K.; Nonomura, Y.; Fluck, E.

    1993-01-01

    The bis-adducts of iron chlorophylls with poly(4-vinylpyridine-costyrene) (PVP) have been prepared and characterized by 57 Fe Moessbauer spectroscopy. The Moessbauer parameters of the PVP-adducts of iron chlorophylls are typical of low-spin iron(II) complexes. The central iron(III) ion is spontaneously reduced upon the axial coordination of PVP to iron(III) chlorophylls. The general tendency in the spontaneous reduction of the iron(III) chlorophylls has been interpreted in terms of the σ-donor and π-acceptor power of the axial macromolecular ligand. (orig.)

  9. High resolution Moessbauer spectroscopy with 67Zn in metallic systems

    Potzel, W.

    1985-01-01

    Moessbauer experiments on metallic systems are described where the high resolution 93.3 keV resonance in 67 Zn is used. In the first part, the Cu-Zn alloy system is investigated and the high energy resolution of this Moessbauer transition is employed to determine small changes of the s-electron density at the 67 Zn nucleus when the Zn concentration is changed. In the second part, Zn metal is taken as an example to demonstrate that the 93.3 keV transition is also extremely sensitive to small changes of lattice dynamical effects. 7 refs., 18 figs. (author)

  10. Moessbauer spectroscopy of the cephalin+SnCl4 system

    Rochev, Ya.V.; Kevdin, O.P.; Kivrina, N.K.; Gilbukh, E.A.; May, L.

    1981-01-01

    A technique is developed for introducing Moessbauer labels into lipid systems. With the use of stannic chloride as a label the temperature dependences are studied for parameters of Moessbauer spectra of the cephalin+stannic chloride lipid system and of the corresponding model lipid-free system. Conclusions are made on the structure of tin complexes in the systems under study; for lipid system a line broadening is observed at temperatures above -64 deg C, that is probably due to conformational change in the lipid matrix. On the assumption of different diffusion models, the diffusion characteristics of the system studied are estimated at various temperatures. (author)

  11. Study of clays by means of Moessbauer spectoscopy

    Marticorena, B.

    1982-01-01

    A Moessbauer spectroscopic method has been applied to study layers of clays originating from different places and ceramic from Pachacamac, an archeological site near Lima. We have performed a Moessbauer analysis of the samples mentioned above, submitting them to a thermal treatment in order to determine the influcence on the mineral ferrous compounds of the time and the baking atmoshere. The results obtained do not allow us to conclude that such a method is useful either in the case of clays and/or ceramics which are coming from different places or of archeological

  12. Moessbauer study of amorphous alloys irradiated with energetic heavy ions

    Kuzmann, E.; Spirov, I.N.

    1984-01-01

    The Moessbauer spectroscopy was applied to study radiation damages in amorphous alloys irradiated with 40 Ar (E=225 MeV) or 132 Xe (E=120 MeV) ions at room temperature. In the magnetically splitted Moessbauer spectra the dose-dependent decreases of the intensity of the 2nd and 5th lines as well as of the average hyperfine magnetic field were observed. The changes weAe also analysed using the hyperfine field distribution obtained from the spectra. The results are interpreted in terms of defect creation and structural changes of shortrange order of irradiated amorphoys alloys

  13. A study on radiation shield design of storage facility for low and intermediate level radioactive waste in Bangladesh

    Khan, JJahirul Haque

    2005-02-01

    Bangladesh has no nuclear power reactor but has only one 3 MW TRIGA Mark-II Research Reactor. The Bangladesh Atomic Energy commission (BAEC) operates a 3 MW TRIGA Mark-II Research Reactor and maintains not only the nuclear facilities at its Atomic Energy Research Establishment (AERE) at Savar (near Dhaka) but also the related radiation facilities the whole country. The main sources of radioactive wastes result from the use of sealed and unsealed radiation sources in medicine industry, research, agriculture, etc as well as from operation and maintenance of the nuclear facilities the whole country. As a result radioactive wastes are increasing day by day and these wastes are classified as low and intermediate level radioactive waste (LILW) following the radiation safety philosophy of IAEA recommendations in Bangladesh. Radioactive waste is very sensitive issue to public and environment from the hazardous standpoint of ionizing radiation. Therefore, storage facility of LILW is very essential for safe radioactive waste management in Bangladesh and in parallel: this study is of a great importance due to new installation of this storage facility in future. The basic objective of this study is to recommend the radiation shield design parameters of the installation of storage facility for low and intermediate level radioactive waste from the points of view of radiation safety and sensitivity analysis. The shield design of this installation has been carried out with the Monte Carlo Code MCNP4C and the point Kernel Code Micro Shield 5.05 respectively considering the ICRP-60 (1990) recommendations for occupational exposure limit (10 μ Sv/hr). For more safety purpose every equivalent dose rate at different positions of this installation is considered below 9 μ Sv/hr in this study. The radiation shield design parameters are recommended based on MCNP4C calculated results than those of Micro Shield due to more credible results and these parameters are: (I) 51 cm thickness of

  14. Effects of post-disposal gas generation in a repository for spent fuel, high-level waste and long-lived intermediate level waste sited in opalinus clay

    Johnson, L.; Marschall, P.; Zuidema, P.; Gribi, P.

    2004-07-01

    This comprehensive report issued by the Swiss National Cooperative for the Disposal of Radioactive Waste NAGRA takes a look at post-disposal gas generation in a repository for spent fuel and highly radioactive wastes in Opalinus clay strata. This study provides a comprehensive treatment of the issue of gas generation in a repository for spent fuel (SF), vitrified high-level waste (HLW) and long-lived intermediate-level waste (ILW), sited in the Opalinus clay of the Zuercher Weinland in northern Switzerland. The issue of how gas generation in and transport from waste repositories may influence disposal system performance has been under study for many years, both at Nagra and internationally. The report consists of three main parts: (i) A synthesis of basic information on the host rock and on details of repository construction; (ii) A discussion on gas transport characteristics of the engineered barrier system and the geosphere; (iii) A discussion on the effects of gas on system performance, based on the available information on gas generation, gas transport properties and gas pathways provided in the previous parts of the report. Simplified model calculations based on a mass balance approach for the gas generated within the repository are presented and discussed

  15. France's State of the Art Distributed Optical Fibre Sensors Qualified for the Monitoring of the French Underground Repository for High Level and Intermediate Level Long Lived Radioactive Wastes.

    Delepine-Lesoille, Sylvie; Girard, Sylvain; Landolt, Marcel; Bertrand, Johan; Planes, Isabelle; Boukenter, Aziz; Marin, Emmanuel; Humbert, Georges; Leparmentier, Stéphanie; Auguste, Jean-Louis; Ouerdane, Youcef

    2017-06-13

    This paper presents the state of the art distributed sensing systems, based on optical fibres, developed and qualified for the French Cigéo project, the underground repository for high level and intermediate level long-lived radioactive wastes. Four main parameters, namely strain, temperature, radiation and hydrogen concentration are currently investigated by optical fibre sensors, as well as the tolerances of selected technologies to the unique constraints of the Cigéo's severe environment. Using fluorine-doped silica optical fibre surrounded by a carbon layer and polyimide coating, it is possible to exploit its Raman, Brillouin and Rayleigh scattering signatures to achieve the distributed sensing of the temperature and the strain inside the repository cells of radioactive wastes. Regarding the dose measurement, promising solutions are proposed based on Radiation Induced Attenuation (RIA) responses of sensitive fibres such as the P-doped ones. While for hydrogen measurements, the potential of specialty optical fibres with Pd particles embedded in their silica matrix is currently studied for this gas monitoring through its impact on the fibre Brillouin signature evolution.

  16. Estimation of expenses for low and intermediate level radioactive waste repository project in Croatia up to site license acquisition

    Schaller, A.; Lokner, V.; Subasic, D.

    2003-01-01

    The expenses needed for development of low- and intermediate level radioactive waste (LILW) repository project in Croatia include: (a) preliminary activities, (b) preparatory activities, and (c) preparing of environmental impact study. The first group of expenses are referring to the project leading activities, project plan updating, build-up of required infrastructure, preparing of licensing documentation, site investigations, data acquisition programme, pre-operational radio-ecological monitoring, modelling, safety analysis (first iteration) and public related activities. Preparatory activities are referring to purchasing of land for repository and preparatory activities for carrying out of on-site investigations, while third group of expenses are related to preparation and validation of Environmental impact study. It was found out that about 50 % of total expenses refer to build-up of infrastructure. Additional 25 % finances are related to radio-ecological monitoring, site investigations and development of calculations and models, while remaining 25 % of total estimated sum is expected to be spent for repository safety assessment, public relations, purchasing and preparing the on-site terrain for construction, etc. It was calculated 607 EUR per m3 of LILW to be needed up to site license acquisition. According to the world-wide practice, by extrapolating of additional expenses necessary for construction of the repository and acquisition of operational license, it comes out the cost of 1.723 EUR per m3 of LILW for shallow-ground and 2.412 EUR per m3 of LILW for tunnel repository. The estimated expenses for Croatia are within the span of expenses for the same purpose in the countries considered. Expected duration of the project performance up to acquisition of the site license is 4 years and 3 months. (author)

  17. Long-Term Performance of Silo Concrete in Low- and Intermediate-Level Waste (LILW) Disposal Facility

    Jung, Hae Ryong; Kwon, Ki Jung; Lee, Seung Hyun; Lee, Sung Bok; Jeong, Yi Yeong; Yoon, Eui Sik; Kim, Do Gyeum

    2012-01-01

    Concrete has been considered one of the engineered barriers in the geological disposal facility for low- and intermediate-level wastes (LILW). The concrete plays major role as structural support, groundwater infiltration barrier, and transport barrier of radionuclides dissolved from radioactive wastes. It also works as a chemical barrier due to its high pH condition. However, the performance of the concrete structure decrease over a period of time because of several physical and chemical processes. After a long period of time in the future, the concrete would lose its effectiveness as a barrier against groundwater inflow and the release of radionuclides. An subsurface environment below the frost depth should be favorable for concrete longevity as temperature and moisture variation should be minimal, significantly reducing the potential of cracking due to drying shrinkage and thermal expansion and contraction. Therefore, the concrete structures of LILW disposal facilities below groundwater table are expected to have relatively longer service life than those of near-surface or surface concrete structures. LILW in Korea is considered to be disposed of in the Wolsong LILW Disposal Center which is under construction in geological formation. 100,000 waste packages are expected to be disposed in the 6 concrete silos below EL -80m in the Wolsong LILW Disposal Center as first stage. The concrete silo has been considered the main engineered barrier which plays a role to inhibit water inflow and the release of radionuclides to the environments. Although a number of processes are responsible for the degradation of the silo concrete, it is concluded that a reinforcing steel corrosion cause the failure of the silo concrete. Therefore, a concrete silo failure time is calculated based on a corrosion initiation time which takes for chloride ions to penetrate through the concrete cover, and a corrosion propagation time. This paper aims to analyze the concrete failure time in the

  18. Hydrogeologic modelling in support of a proposed Deep Geologic Repository in Canada for low and intermediate level radioactive waste

    Sykes, J.F.; Normani, S.D.; Yin, Y. [Waterloo Univ., ON (Canada). Dept. of Civil and Environmental Engineering; Sykes, E.A.; Jensen, M.R. [Nuclear Waste Management Organization, Toronto, ON (Canada)

    2009-07-01

    Ontario Power Generation (OPG) has proposed the construction of a Deep Geologic Repository (DGR) for low and intermediate level radioactive waste at the Bruce site on the shore of Lake Huron near Tiverton, Ontario. The DGR is to be excavated at a depth of about 680 m within argillaceous limestones of Ordovician age. A saturated regional-scale and site-scale numerical modelling study has been completed in order to evaluate the safety of storing radioactive waste at the site and to better understand the geochemistry and hydrogeology of the formations surrounding the proposed DGR. This paper reported on the regional-scale base-case modelling and analysis of the measured pressure profile in deep boreholes at the DGR site. The numerical modelling study provided a framework to investigate the groundwater flow system as it relates to, and potentially affects, the safety and long-term performance of the DGR. A saturated groundwater flow model was also developed using FRAC3DVS-OPG. The objective of regional-scale groundwater modelling of the Paleozoic sedimentary sequence underlying southwestern Ontario was to provide a basis for the assembly and integration of site-specific geoscientific data and to explain the influence of parameter and scenario uncertainty on predicted long-term geosphere barrier performance. The base-case analysis showed that solute transport in the Ordovician and lower Silurian is diffusion dominant. For the base-case parameters, the estimated mean life expectancy for the proposed DGR is more than 8 million years. The possible presence of a gas phase in the rock between the Cambrian and the Niagaran was not considered in the analyses of this paper. 9 refs., 2 tabs., 10 figs.

  19. Treatment, conditioning and packaging for final disposal of low and intermediate level waste from Cernavoda: a techno-economic assessment

    Suryanarayan, S.; Husain, A. [Kinectrics Inc., Toronto, ON (Canada); Fellingham, L.; Nesbitt, V. [Nuvia Ltd., Didcot, Oxfordshire (United Kingdom); Toro, L. [Mate-fin, Bucharest (Romania); Simionov, V.; Dumitrescu, D. [Cernavoda Nuclear Power Plant, Cernavoda (Romania)

    2011-07-01

    National Nuclearelectrica Society (SNN) owns and operates two CANDU-6 plants at Cernavoda in Romania. Two additional units are expected to be built on the site in the future. Low and intermediate level short-lived radioactive wastes from Cernavoda are planned to be disposed off in a near-surface repository to be built at Saligny. The principal waste streams are IX resins, filters, compactable wastes, non-compactables, organic liquids and oil-solid mixtures. Their volumetric generation rates per reactor unit are estimated to be: IX resins (6 m{sup 3}/y), filters (2 m{sup 3}/y), compactables (23 m{sup 3}/y) and non-compactables (15 m{sup 3}/y). A techno-economic assessment of the available options for a facility to treat and condition Cernavoda's wastes for disposal was carried out in 2009 based on projected waste volumes from all four units. A large number of processes were first screened to identify viable options. They were further considered to develop overall processing options for each waste stream. These were then consolidated to obtain options for the entire plant by minimizing the number of unit operations required to process the various waste streams. A total of 9 plant options were developed for which detailed costing was undertaken. Based on a techno-economic assessment, two top ranking plant options were identified. Several scenarios were considered for implementing these options. Amongst them, a contractor run operation of a facility located on the Cernavoda site was considered to be more cost effective than operating the facility using SNN personnel. (author)

  20. The intermediates take it all: asymptotics of higher criticism statistics and a powerful alternative based on equal local levels.

    Gontscharuk, Veronika; Landwehr, Sandra; Finner, Helmut

    2015-01-01

    The higher criticism (HC) statistic, which can be seen as a normalized version of the famous Kolmogorov-Smirnov statistic, has a long history, dating back to the mid seventies. Originally, HC statistics were used in connection with goodness of fit (GOF) tests but they recently gained some attention in the context of testing the global null hypothesis in high dimensional data. The continuing interest for HC seems to be inspired by a series of nice asymptotic properties related to this statistic. For example, unlike Kolmogorov-Smirnov tests, GOF tests based on the HC statistic are known to be asymptotically sensitive in the moderate tails, hence it is favorably applied for detecting the presence of signals in sparse mixture models. However, some questions around the asymptotic behavior of the HC statistic are still open. We focus on two of them, namely, why a specific intermediate range is crucial for GOF tests based on the HC statistic and why the convergence of the HC distribution to the limiting one is extremely slow. Moreover, the inconsistency in the asymptotic and finite behavior of the HC statistic prompts us to provide a new HC test that has better finite properties than the original HC test while showing the same asymptotics. This test is motivated by the asymptotic behavior of the so-called local levels related to the original HC test. By means of numerical calculations and simulations we show that the new HC test is typically more powerful than the original HC test in normal mixture models. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Long-Term Performance of Silo Concrete in Low- and Intermediate-Level Waste (LILW) Disposal Facility

    Jung, Hae Ryong; Kwon, Ki Jung; Lee, Seung Hyun; Lee, Sung Bok; Jeong, Yi Yeong [Korea Radioactive-waste Management Corporation, Daejeon (Korea, Republic of); Yoon, Eui Sik [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Kim, Do Gyeum [Korea Institute of Construction Technology, Goyang (Korea, Republic of)

    2012-05-15

    Concrete has been considered one of the engineered barriers in the geological disposal facility for low- and intermediate-level wastes (LILW). The concrete plays major role as structural support, groundwater infiltration barrier, and transport barrier of radionuclides dissolved from radioactive wastes. It also works as a chemical barrier due to its high pH condition. However, the performance of the concrete structure decrease over a period of time because of several physical and chemical processes. After a long period of time in the future, the concrete would lose its effectiveness as a barrier against groundwater inflow and the release of radionuclides. An subsurface environment below the frost depth should be favorable for concrete longevity as temperature and moisture variation should be minimal, significantly reducing the potential of cracking due to drying shrinkage and thermal expansion and contraction. Therefore, the concrete structures of LILW disposal facilities below groundwater table are expected to have relatively longer service life than those of near-surface or surface concrete structures. LILW in Korea is considered to be disposed of in the Wolsong LILW Disposal Center which is under construction in geological formation. 100,000 waste packages are expected to be disposed in the 6 concrete silos below EL -80m in the Wolsong LILW Disposal Center as first stage. The concrete silo has been considered the main engineered barrier which plays a role to inhibit water inflow and the release of radionuclides to the environments. Although a number of processes are responsible for the degradation of the silo concrete, it is concluded that a reinforcing steel corrosion cause the failure of the silo concrete. Therefore, a concrete silo failure time is calculated based on a corrosion initiation time which takes for chloride ions to penetrate through the concrete cover, and a corrosion propagation time. This paper aims to analyze the concrete failure time in the

  2. Immobilization of simulated low and intermediate level waste in alkali-activated slag-fly ash-metakaolin hydroceramics

    Wang, Jin, E-mail: wjin761026@163.com [State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials, Southwest University of Science and Technology, Mianyang 621010, Sichuan (China); School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, Sichuan (China); Wang, Jun-xia; Zhang, Qin [School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, Sichuan (China); Li, Yu-xiang [State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials, Southwest University of Science and Technology, Mianyang 621010, Sichuan (China); School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, Sichuan (China)

    2016-04-15

    Highlights: • Evaluation of the suitability of ASFMH for solidifying simulated S-LILW. • The introduction of S-LILW avails forming zeolitic phases of ASFMH waste forms. • The ASFMH waste forms have low leachability and high compressive strength. - Abstract: In the current study, the alkali-activated slag-fly ash-metakaolin hydroceramic (ASFMH) waste forms for immobilizing simulated low and intermediate level waste (S-LILW) were prepared by hydrothermal process. The crystalline phase compositions, morphology, compressive strength and aqueous stability of S-LILW ASFMH waste forms were investigated. The results showed that the main crystalline phases of S-LILW ASFMH waste forms were analcime and zeolite NaP1. The changes of Si/Al molar ratio (from 1.7 to 2.2) and Ca/Al molar ratio (from 0.15 to 0.35) had little effect on the phase compositions of S-LILW ASFMH waste forms. However, the hydrothermal temperature, time as well as the content of S-LILW (from 12.5 to 37.5 wt%) had a major impact on the phase compositions. The compressive strength of S-LILW ASFMH waste forms was not less than 20 MPa when the content of S-LILW reached 37.5 wt%. In addition, the aqueous stability testing was carried out using the standard MCC-1 static leach test method; the normalized elemental leach rates of Sr and Cs were fairly constant in a low value below 5 × 10{sup −4} g m{sup −2} d{sup −1} and 3 × 10{sup −4} g m{sup −2} d{sup −1} after 28 days, respectively. It is indicated that ASFMH waste form could be a potential host for safely immobilizing LILW.

  3. Use of tactual materials on the achievement of content specific vocabulary and terminology acquisition within an intermediate level science curriculum

    Terry, Brian H.

    In this quasi-experimental study, the researcher investigated the effectiveness of three tactual strategies and one non-tactual strategy of content specific vocabulary acquisition. Flash cards, task cards, and learning wheels served as the tactual strategies, and vocabulary review sheets served as a non-tactual strategy. The sample (n=85) consisted of all middle school students in a small high performing middle school located in the northern suburbs of New York City. All of the vocabulary words and terms came from the New York State Intermediate Level Science Core Curriculum. Pre-tests and post-tests were used to collect the data. A repeated measures ANOVA was conducted on the gain scores from each of the treatments. Multiple paired sample t-tests were conducted to analyze the results. Repeated measures ANOVAs were used to determine if there was a variance between the academic achievement levels of the students, gender, and grade level for each of the treatments. All of the treatments significantly improved the science achievement of the students, but significance was found between them. Significance was found between the achievement groups with the above average students attaining a higher mean on the pre-test and post-test for each treatment, whereas the below average students had the lowest mean on both assessments. The sixth grade students showed significant improvement over the seventh grade students while using the flash cards (p=.004) and learning wheel (p=.007). During the learning wheel treatment, the males scored significantly better (p=.021) than the females on the pre-test and post-test. During the worksheet treatment, significance (p=.034) was found between gender and achievement group. The below average male students had the greatest gain from the pre-test to the post-test, but the post-test mean was still the lowest of the groups. Limitations, implications for future research and current practice are discussed. Key words are: flash cards, task cards

  4. Localization of the antimony impurity atoms in the PbTe lattice determined by the Moessbauer emission spectroscopy

    Masterov, V.F.; Nasredinov, F.S.; Nemov, S.A.; Seregin, P.P.; Troitskaya, N.N.; Bondarevskij, S.I.

    1997-01-01

    The 119 Sb ( 119m Sn) emission Moessbauer spectroscopy has shown that a localization of the antimony impurity atoms in the PbTe lattice is affected by the conductivity type of the host material, the antimony atoms occupied mainly anion and cation sites in n-type and p-type samples, respectively. The 119 Sn impurity in the anion sublattice of PbTe formed an decay. Its charge state was shown to be independent of the Fermi level position

  5. Cu(2) dynamical correlations in YBa2Cu3Ox studied by Moessbauer spectroscopy on substituted 170Yb3+

    Hodges, J.A.; Bonville, P.; Imbert, P.; Jehanno, G.

    1990-01-01

    Using Moessbauer spectroscopy, we follow the thermal dependence of the fluctuation rate of the Cu(2) internal (molecular) field acting on a 170 Yb 3+ probe diluted at the Y 3+ sites. We use the fluctuations of this field to track the collective fluctuations of the nearest neighbour correlated Cu(2) moments. Results are presented for oxygen levels x = 6.0 and 6.35 and for T ≤ 80K

  6. A Western Blot-based Investigation of the Yeast Secretory Pathway Designed for an Intermediate-Level Undergraduate Cell Biology Laboratory

    Hood-DeGrenier, Jennifer K.

    2008-01-01

    The movement of newly synthesized proteins through the endomembrane system of eukaryotic cells, often referred to generally as the secretory pathway, is a topic covered in most intermediate-level undergraduate cell biology courses. An article previously published in this journal described a laboratory exercise in which yeast mutants defective in…

  7. The storage center of short life low and intermediate level radioactive wastes; Le centre de stockage des dechets de faible et moyenne activite a vie courte

    NONE

    2008-07-01

    Situated at 50 km of Troyes, the Aube Center was opened in 1992 in order to take over from the Manche Center, for the surface storage of low life low and intermediate level radioactive wastes. It offers an answer to manage safely theses wastes at an industrial scale during 50 years. (A.L.B.)

  8. Comparison of three-phase three-level voltage source inverter with intermediate dc–dc boost converter and quasi-Z-source inverter

    Panfilov, Dmitry; Husev, Oleksandr; Blaabjerg, Frede

    2016-01-01

    This study compares a three-phase three-level voltage source inverter with an intermediate dc-dc boost converter and a quasi-Z-source inverter in terms of passive elements values and dimensions, semiconductor stresses, and overall efficiency. A comparative analysis was conducted with relative...

  9. The partnership experience on the disposal of low- and intermediate-level short-lived waste in Belgium

    Preter, P. de; Cool, W.; Hooft, E.; Waffelaert, A.; Blommaert, J.; Draulans, J.

    2008-01-01

    With the governmental decision of January 16, 1998, the long-term storage option for the low- and intermediate-level short-lived waste (category A waste) was abandoned and ONDRAF/NIRAS was given the mission to further examine the options of deep and surface disposal, in order to prepare a federal decision on the technical option to be developed. ONDRAF/NIRAS was also asked to develop the methods and structures of interaction with the local stakeholders, and to limit its siting activities to nuclear and candidate municipalities. This brought ONDRAF/NIRAS to the concept of local partnerships with interested municipalities, and during the pre-project phase 1998-2006 partnerships were created with the municipalities of Dessel (STOLA-Dessel, 1999), Mol (MONA, 2000) and Fleurus-Farciennes (PaLoFF, 2003). On 23 June, 2006 the Belgian Government decided that category A waste will be disposed of in a near-surface repository on the territory of the Dessel municipality. This decision implies that ONDRAF/NIRAS, in further interaction with the local stakeholders, can start the preparation of a licence application. This decision was the endpoint of the pre-project phase (1998-2006) and was based on the final reports of the partnerships of Dessel (STOLA-Dessel, now STORA) and Mol (MONA), approved by their municipality councils, and on ONDRAF/NIRAS final report, confirming the feasibility of the proposed disposal systems. As the municipality council of Fleurus did not approve the final report of the partnership PaLoFF, ONDRAF/NIRAS did not submit this report to the responsible minister. The preceding positive local decision in both Dessel (May 2005) and Mol (July 2005), and both on the partnership and municipality council level, to accept, under certain conditions, a disposal facility on their territory was the result of a 6 years long process of discussions within the partnership of all aspects of the disposal system and its integration in the municipality. During these

  10. Concentration Limits in the Cement Based Swiss Repository for Long-lived, Intermediate-level Radioactive Wastes (LMA)

    Berner, Urs

    1999-12-01

    The Swiss repository concept for long-lived, intermediate-level radioactive wastes (LMA), in Swiss terminology) foresees cylindrical concrete silos surrounded by a ring of granulated bentonite to deposit the waste. As one of the possible options and similar to the repository for high level wastes, the silos will be located in a deep crystalline host rock. Solidified with concrete in steel drums, the waste is stacked into a silo and the silo is then backfilled with a porous mortar. To characterize the release of radionuclides from the repository, the safety assessment considers first the dissolution into the pore water of the concrete, and then diffusion through the outer bentonite ring into the deep crystalline groundwater. For 19 safety relevant radionuclides (isotopes of U, Th, Pa, Np, Pu, Am, Ni, Zr, Mo, Nb, Se, Sr, Ra, Tc, Sn, I, C, Cs, Cl) the report recommends maximum elemental concentrations to be expected in the cement pore water of the particularly considered repository. These limits will form the parameter base for subsequent release model chains. Concentration limits in a geochemical environment are usually obtained from thermodynamic equilibrium calculations performed with geochemical speciation codes. However, earlier studies revealed that this procedure does not always lead to reliable results. Main reasons for this are the complexity of the systems considered, as well as the lacking completeness of, and the uncertainty associated with the thermodynamic data. To improve the recommended maximum concentrations for a distinct repository design, this work includes additional design- and system-dependent criteria. The following processes, inventories and properties are considered in particular: a) recent experimental investigations, particularly from cement systems, b) thermodynamic model calculations when reliable data are available, c) total inventories of radionuclides, d) sorption- and co-precipitation processes, e) dilution with stable isotopes, f

  11. Multi-shell spherical GaAs /AlxGa1-x As quantum dot shells-size distribution as a mechanism to generate intermediate band energy levels

    Rodríguez-Magdaleno, K. A.; Pérez-Álvarez, R.; Martínez-Orozco, J. C.; Pernas-Salomón, R.

    2017-04-01

    In this work the generation of an intermediate band of energy levels from multi-shell spherical GaAs /AlxGa1-x As quantum dot shells-size distribution is reported. Within the effective mass approximation the electronic structure of a GaAs spherical quantum-dot surrounded by one, two and three shells is studied in detail using a numerically stable transfer matrix method. We found that a shells-size distribution characterized by continuously wider GaAs domains is a suitable mechanism to generate the intermediate band whose width is also dependent on the Aluminium concentration x. Our results suggest that this effective mechanism can be used for the design of wider intermediate band than reported in other quantum systems with possible solar cells enhanced performance.

  12. Moessbauer effect study on the corrosion of an oil refinery

    Da Costa, M.I. Jr.; Kunrath, J.I.; Moro, J.T.; Englert, G.; Comparsi, L.U.; Mueller, I.L.

    1994-01-01

    Metallic coupons are placed in strategical points of an oil refining plant in order to control the amount of corrosion produced by amine stripping of H 2 S from liquefied oil and combustible gases. This paper reports some of the results obtained by CEMS and transmission Moessbauer spectroscopy for the corrosion products formed on such coupons. (orig.)

  13. Moessbauer spectroscopic studies of magnetically ordered biological materials

    Dickson, D.P.E.

    1987-01-01

    This paper discusses recent work showing the application of Moessbauer spectroscopy to the study of the properties of the magnetically ordered materials which occur in a variety of biological systems. These materials display a diversity of behaviour which provides good examples of the various possibilities which can arise with iron-containing particles of different compositions and sizes. (orig.)

  14. Magnetic and thermal Moessbauer effect scans: a new approach

    Pasquevich, G. A.; Zelis, P. Mendoza; Sanchez, F. H.; Fernandez van Raap, M. B.; Veiga, A.; Martinez, N.

    2006-01-01

    Moessbauer transmission recorded at fixed photon energies as a function of a given physical parameter such as temperature, external field, etc. (Moessbauer scan), is being developed as a useful quantitative tool, complementary of Moessbauer spectroscopy. Scans are performed at selected energies, suitable for the observation of a given physical property or process. It is shown that one of main advantages of this approach is the higher speed at which the external physical parameter can be swept, which allows the recording of quasi-continuous experimental response functions as well as the study of processes which occur too fast to be followed by Moessbauer spectroscopy. The applications presented here are the determination of the temperature dependence of the 57 Fe hyperfine field in FeSn 2 , the thermal evolution and nanocrystallization kinetics of amorphous Fe 73.5 Si 13.5 Cu 1 Nb 3 B 9 and the measurement of the dynamic response of Fe magnetic moments in nanocrystalline Fe 90 Zr 7 B 3 to an external ac field.

  15. Moessbauer thermal scan study of a spin crossover system

    Zelis, P Mendoza; Pasquevich, G A; Sanchez, F H; Veiga, A; Cabrera, A F [Departamento de Fisica, FCE-UNLP, La Plata (Argentina); Ceolin, M [Instituto de Investigaciones FIsico-Quimicas Teoricas y Aplicadas (UNLP-CONICET), La Plata (Argentina); Coronado-Miralles, E; Monrabal-Capilla, M; Galan-Mascaros, J R, E-mail: pmendoza@fisica.unlp.edu.a [Instituto de Ciencias Moleculares, Universidad de Valencia, Valencia (Spain)

    2010-03-01

    Programmable Velocity equipment was used to perform a Moessbauer Thermal Scans to allow a quasi-continuous temperature study of the magnetic transition between the low-spin and a high-spin configurations in [Fe(Htrz){sub 2}(trz)](BF4) system. The material was studied both in bulk as in nanoparticles sample forms.

  16. Study of chicken liver and spleen by Moessbauer spectroscopy

    Oshtrakh, M. I., E-mail: oshtrakh@mail.utnet.ru [Ural State Technical University-UPI, Division of Applied Biophysics, Faculty of Physical Techniques and Devices for Quality Control (Russian Federation); Milder, O. B.; Semionkin, V. A. [Ural State Technical University-UPI, Faculty of Experimental Physics (Russian Federation); Malakheeva, L. I. [Simbio Holding, Science Consultation Department (Russian Federation); Prokopenko, P. G. [Russian State Medical University, Faculty of Biochemistry (Russian Federation)

    2005-09-15

    A preliminary study of purified normal human liver ferritin, normal chicken liver and spleen tissues in lyophilized form showed differences in room temperature Moessbauer hyperfine parameters. An additional study of liver and spleen tissues with lower iron content from chicken with lymphoid leukemia indicated small differences between the quadrupole splittings in these samples compared with those in normal tissues.

  17. Recent development in the evaluation of Moessbauer line intensities

    Spiering, H.

    1985-01-01

    The angular dependence of the intensities of pure or mixed multipole transitions is formulated in a new fashion, which takes into account arbitrary texture of the Moessbauer absorber ranging from complete orientation (single crystals) over preferred orientation to random powders and an anisotropic absorption fraction of the nuclei. The application of the theory is demonstrated by means of typical examples from the literature. (orig.)

  18. Study of chicken liver and spleen by Moessbauer spectroscopy

    Oshtrakh, M. I.; Milder, O. B.; Semionkin, V. A.; Malakheeva, L. I.; Prokopenko, P. G.

    2005-01-01

    A preliminary study of purified normal human liver ferritin, normal chicken liver and spleen tissues in lyophilized form showed differences in room temperature Moessbauer hyperfine parameters. An additional study of liver and spleen tissues with lower iron content from chicken with lymphoid leukemia indicated small differences between the quadrupole splittings in these samples compared with those in normal tissues.

  19. Moessbauer study of iron uptake in cucumber root

    Kovacs, K.; Kuzmann, E., E-mail: kuzmann@para.chem.elte.hu [Eoetvoes Lorand University, Research Group for Nuclear Methods in Structural Chemistry, Hungarian Academy of Sciences, Department of Nuclear Chemistry (Hungary); Fodor, F. [Eoetvoes Lorand University, Department of Plant Physiology and Molecular Plant Biology (Hungary); Vertes, A. [Eoetvoes Lorand University, Research Group for Nuclear Methods in Structural Chemistry, Hungarian Academy of Sciences, Department of Nuclear Chemistry (Hungary); Kamnev, A. A. [Russian Academy of Sciences, Institute of Biochemistry and Physiology of Plants and Microorganisms (Russian Federation)

    2005-09-15

    {sup 57}Fe Moessbauer spectroscopy was used to study the uptake and distribution of iron in the root of cucumber plants grown in iron-deficient modified Hoagland nutrient solution and put into iron-containing solution with 10 {mu}M Fe citrate enriched with {sup 57}Fe (90%) only before harvesting. The Moessbauer spectra of the frozen roots exhibited two Fe{sup 3+} components with typical average Moessbauer parameters of {delta} = 0.5 mm s{sup -1}, {Delta} = 0.46 mm s{sup -1} and {delta} = 0.5 mm s{sup -1}, {Delta} = 1.2 mm s{sup -1} at 78 K and the presence of an Fe{sup 2+} doublet, assigned to the ferrous hexaaqua complex. This finding gives a direct evidence for the existence of Fe{sup 2+} ions produced via root-associated reduction according to the mechanism proposed for iron uptake for dicotyledonous plants. Monotonous changes in the relative content of the components were found with the time period of iron supply. The Moessbauer results are interpreted in terms of iron uptake and transport through the cell wall and membranes.

  20. High field Moessbauer spectroscopy using water-cooled magnets

    Chappert, J.; Regnard, J. R.

    1974-07-01

    A high field Moessbauer spectrometer using a Bitter coil producing fields of up to 155 kOe is described. Problems encountered in the design of this type of equipment are discussed and preliminary results demonstrating the performance of the spectrometer are presented.

  1. Application of Moessbauer spectroscopy to study archaeological Egyptian pottery

    Eissa, N.A.

    1988-01-01

    Moessbauer spectra have been used as ''fingerprints'' in obtaining information an ancient Egyptian pottery and in fine art. An empirical relation has been found that connects the natural radiation dose with the intensity ratio of the two non-magnetic central peaks. It was suggested that this relation be used for dating ancient pottery. 8 refs, 13 figs, 2 tabs

  2. Application of Moessbauer effect in the study of silicon steels

    Lonsky, B.; Wiglasz, V.; Prejsa, M.

    1975-11-01

    The results for 1975 are presented of the research task: Application of the Moessbauer effect in the study of silicon steels. Moessbauer spectra were measured on Czechoslovak made materials of Eo 10 quality and of foreign made material of M2H quality in dependence on tensile stress. Moessbauer spectra were measured on identical samples with electrotechnical insulation and after the removal thereof, with the aim of ascertaining the effect of this insulation. All measurements were evaluated on the basis of changes in the intensity ratios of the first and second lines of the spectrum which characterize the domain structure. These measurements have confirmed that electrotechnical insulation forms in the basic material small tensile stresses which improve the magnetic properties of the material. Moessbauer spectra were measured using the absorption method on identical materials in thin foils with the aim of investigating the configuration of Si atoms in the Fe3%Si alloy. It was found that both materials contain Si atoms in both the first and the second coordination spheres. (author)

  3. Moessbauer study of rock paintings from Minas Gerais (Brazil)

    Costa, G.M. da; Jesus Filho, M.F. de; Cruz Souza, L.A.

    1991-01-01

    Four samples of a wall containing rock paintings have been studied by Moessbauer spectroscopy in combination with optical microscopy analysis and X-ray diffraction. Hematite and goethite were identified as the pigments responsible for the colors and the mineral tinsleyite, as the principal component of a light pink layer that is present in some parts of the wall. (orig.)

  4. Current opinion about maximum entropy methods in Moessbauer spectroscopy

    Szymanski, K

    2009-01-01

    Current opinion about Maximum Entropy Methods in Moessbauer Spectroscopy is presented. The most important advantage offered by the method is the correct data processing under circumstances of incomplete information. Disadvantage is the sophisticated algorithm and its application to the specific problems.

  5. SEM, optical, and Moessbauer studies of submicrometer chromite in Allende

    Housley, R. M.

    1982-01-01

    New scanning electron and optical microscope results are presented showing that sub-micrometer chromite is abundant along healed cracks and grain boundaries in Allende chondrule olivine. Some wider healed cracks also contain pentlandite and euhedral Ni3Fe grains. Also reported are Moessbauer measurements on Allende HF-HCl residues confirming a high Fe(+++)/Fe(++) ratio.

  6. The Moessbauer effect and Rudolf enter the Khrushchev thaw

    Gol`danskii, V.I. [Russian Acad. of Sci., Moscow (Russian Federation). N.N. Semenov Inst. of Chem. Phys.

    1994-11-01

    In this article, the earliest works of Soviet scientists on the recoilless resonance scattering of gamma-rays, the first visit of Rudolf Moessbauer to Moscow (1960) and the reciprocal visit of the present author to Los Angeles (1963) are recounted. (orig.)

  7. Italian money tested for forgery by moessbauer spectroscopy

    Ortalli, I.; Pedrazzi, G.; Jiang Keyu; Zhang Xiufang

    1993-01-01

    Italian money has been investigated by Moessbauer spectroscopy. The results indicated that the spectrum of a 10000 lire bank-note consisted of three magnetic sextets and two quadrupole doublets, the spectrum of a 5000 lire note consisted of two Zeeman sextets, but in the 'false' money there are two quadrupole doublets only

  8. A microprocessor based multiscaling data acquisition system for moessbauer spectroscopy

    Bohm, C.; Ekdahl, T.

    1985-01-01

    A microprocessor based data acquisition system is described, which was developed for use in Moessbauer spectroscopy. It is designed to record two spectra simultaneously, one of which could be a calibration spectrum. It is autonomous, but uses a host computer for initialization and permanent storage of data. The host communication software is also described. (Author)

  9. [Gamma scattering in condensed matter with high intensity Moessbauer radiation

    1992-01-01

    This report discusses: quasielastic scattering studies on glycerol; gamma-ray scattering from alkali halides; lattice dynamics in metals; Moessbauer neutron scattering, x-ray diffraction, and macroscopic studies of high T c superconductors containing tungsten; NiAl scattering studies; and atomic interference factors and nuclear Casimir effect

  10. A proportional counter for efficient backscatter Moessbauer effect spectroscopy

    Pawlowski, Z.; Marzec, J.; Cudny, W.; Holnicka, J.; Walentek, J.

    1979-01-01

    The authors present a novel gas-tight proportional counter with flat beryllium windows for backscatter Moessbauer spectroscopy. The krypton-filled counter has a geometry that approaches 2π and a resolution of 12% fwhm for the 14.4 keV line of 57 Fe, and is easy to manufacture. (Auth.)

  11. An assessment of the possible fate of gas generated in a repository for low- and intermediate-level waste

    Leupin, O.X.; Cloet, V.; Marschall, P.; Schwyn, B.; Smith, P.; Zeyer, J.; Bernier-Latmani, R.; Papafotiou, A.; Stroes-Gascoyne, S.

    2016-12-01

    The present study provides an assessment of reactions that result in a gas pressure reduction - also called gas sinks - in a generic deep geological repository for low- and intermediate-level waste in Opalinus Clay. Both chemical reactions and microbial activity may contribute to or reduce gas pressure build-up. A complete synopsis is given, comprising the current state of chemical, microbial and geoscientific understanding of gas generation and consumption in a L/ILW repository. The degradation of organic materials (by both microbial and chemical reactions) and the anoxic corrosion of metals will generate various gaseous products such as hydrogen, carbon dioxide, methane, hydrogen sulphide and ammonia. Some of these gas species are expected to further react with materials present at the point of origin. More particularly, carbon dioxide and hydrogen sulphide are expected to react entirely with e.g. cement, water or iron. Thus, they do not contribute to a gas pressure build-up in the repository. The remaining gas species - mainly hydrogen, methane and small amounts of ammonia - are assumed not to react at the point of origin and can thus contribute to gas pressure build-up. Gas pressure build-up in the L/ILW emplacement caverns will result in gas migrating through the gas permeable seals and through the excavation-damaged zone to reach the operational and construction tunnels where microorganisms may utilise the gas and thus reduce gas pressure build-up. In order to allow bacteria to thrive over longer periods, the backfill material of the operational tunnel needs to have sufficient porosity and a pore water composition for favourable living conditions. Experimental findings at the Mont Terri underground rock laboratory show that bacteria found in borehole water are efficient at oxidising hydrogen as long as sulphate is present in the borehole water. Examples from nature and engineered underground structures provide supporting evidence that these assumptions are

  12. Hydrogeologic modelling in support of a proposed deep geologic repository in Canada for low and intermediate level radioactive waste - 16264

    Sykes, Jonathan F.; Normani, Stefano D.; Yin, Yong; Sykes, Eric A.; Jensen, Mark R.

    2009-01-01

    A Deep Geologic Repository (DGR) for Low and Intermediate Level radioactive waste has been proposed by Ontario Power Generation for the Bruce Nuclear Power Development site in Ontario, Canada. The DGR is to be constructed at a depth of about 680 m below ground surface within the argillaceous Ordovician limestone of the Cobourg Formation. This paper describes a regional-scale geologic conceptual model for the DGR site and analyzes flow system evolution using the FRAC3DVSOPG flow and transport model. This provides a framework for the assembly and integration of site-specific geo-scientific data that explains and illustrates the factors that influence the predicted long-term performance of the geosphere barrier. In the geologic framework of the Province of Ontario, the Bruce DGR is located at the eastern edge of the Michigan Basin. Borehole logs covering Southern Ontario combined with site specific data have been used to define the structural contours at the regional and site scale of the 31 sedimentary strata that may be present above the Precambrian crystalline basement rock. The regional-scale domain encompasses an 18.500 km 2 region extending from Lake Huron to Georgian Bay. The groundwater zone below the Devonian is characterized by units containing stagnant water having high concentrations of total dissolved solids that can exceed 300 g/l. The computational sequence involves the calculation of steady-state density independent flow that is used as the initial condition for the determination of pseudo-equilibrium for a density dependent flow system that has an initial TDS distribution developed from observed data. Long-term simulations that consider future glaciation scenarios include the impact of ice thickness and permafrost. The selection of the performance measure used to evaluate a groundwater system is important. The traditional metric of average water particle travel time is inappropriate for geologic units such as the Ordovician where solute transport is

  13. The hydrogeologic environment for a proposed deep geologic repository in Canada for low and intermediate level radioactive waste - 59285

    Sykes, Jonathan F.; Normani, Stefano D.; Yin, Yong; Jensen, Mark R.

    2012-01-01

    A Deep Geologic Repository (DGR) for low and intermediate level radioactive waste has been proposed by Ontario Power Generation for the Bruce nuclear site in Ontario, Canada. As proposed the DGR would be constructed at a depth of about 680 m below ground surface within the argillaceous Ordovician limestone of the Cobourg Formation. This paper describes the hydrogeology of the DGR site developed through both site characterization studies and regional-scale numerical modelling analysis. The analysis provides a framework for the assembly and integration of the site-specific geo-scientific data and examines the factors that influence the predicted long-term performance of the geosphere barrier. Flow system evolution was accomplished using both the density-dependent FRAC3DVS-OPG flow and transport model and the two-phase gas and water flow computational model TOUGH2-MP. In the geologic framework of the Province of Ontario, the DGR is located on the eastern flank of the Michigan Basin. Borehole logs covering Southern Ontario combined with site-specific data from 6 deep boreholes have been used to define the structural contours and hydrogeologic properties at the regional-scale of the modelled 31 sedimentary strata that may be partially present above the Precambrian crystalline basement rock. The regional-scale domain encompasses an approximately 18500 km 2 region extending from Lake Huron to Georgian Bay. The groundwater zone below the Devonian includes units containing stagnant water having high concentrations of total dissolved solids that can exceed 300 g/L. The Ordovician sediments are significantly under-pressured. The horizontal hydraulic conductivity for the Cobourg limestone is estimated to be 2x10 -14 m/s based on straddle-packer hydraulic tests. The low advective velocities in the Cobourg and other Ordovician units result in solute transport that is diffusion dominant with Peclet numbers less than 0:003 for a characteristic length of unity. Long

  14. An assessment of the possible fate of gas generated in a repository for low- and intermediate-level waste

    Leupin, O.X.; Cloet, V.; Marschall, P.; Schwyn, B. [National Cooperative for the Disposal of Radioactive Waste (NAGRA), Wettingen (Switzerland); Smith, P. [Safety Assessment Management Ltd, Henley-On-Thames, Oxfordshire (United Kingdom); Zeyer, J. [Swiss federal institute of technology (ETH), Zürich (Switzerland); Bernier-Latmani, R. [Swiss federal institute of technology (EPFL), Lausanne (Switzerland); Papafotiou, A. [Intera Inc., Ennetbaden (Switzerland); Stroes-Gascoyne, S. [University of Saskatchewan, Saskatoon, SK S7N 5C5 (Canada)

    2016-12-15

    The present study provides an assessment of reactions that result in a gas pressure reduction - also called gas sinks - in a generic deep geological repository for low- and intermediate-level waste in Opalinus Clay. Both chemical reactions and microbial activity may contribute to or reduce gas pressure build-up. A complete synopsis is given, comprising the current state of chemical, microbial and geoscientific understanding of gas generation and consumption in a L/ILW repository. The degradation of organic materials (by both microbial and chemical reactions) and the anoxic corrosion of metals will generate various gaseous products such as hydrogen, carbon dioxide, methane, hydrogen sulphide and ammonia. Some of these gas species are expected to further react with materials present at the point of origin. More particularly, carbon dioxide and hydrogen sulphide are expected to react entirely with e.g. cement, water or iron. Thus, they do not contribute to a gas pressure build-up in the repository. The remaining gas species - mainly hydrogen, methane and small amounts of ammonia - are assumed not to react at the point of origin and can thus contribute to gas pressure build-up. Gas pressure build-up in the L/ILW emplacement caverns will result in gas migrating through the gas permeable seals and through the excavation-damaged zone to reach the operational and construction tunnels where microorganisms may utilise the gas and thus reduce gas pressure build-up. In order to allow bacteria to thrive over longer periods, the backfill material of the operational tunnel needs to have sufficient porosity and a pore water composition for favourable living conditions. Experimental findings at the Mont Terri underground rock laboratory show that bacteria found in borehole water are efficient at oxidising hydrogen as long as sulphate is present in the borehole water. Examples from nature and engineered underground structures provide supporting evidence that these assumptions are

  15. Long-term degradation of organic polymers under conditions found in deep repositories for low and intermediate-level wastes

    Warthmann, R.; Mosberger, L.; Baier, U.

    2013-06-01

    On behalf of Nagra, the Environmental Biotechnology Section of the Zürich University of Applied Sciences in Wädenswil investigated the potential for microbiological degradation of organic polymers under the conditions found in a deep geological repository for low- and intermediate-level waste (L/ILW). The existing scientific literature on the topic was analysed, some thermodynamic calculations carried out and input was elicited from internationally recognised experts in the field. The study was restricted to a few substances which, in terms of mass, are most significant in the Swiss L/ILW inventory; these are polystyrene (PS), polyvinyl chloride (PVC), other plastics and bitumen. There were no clear indications in the literature that the polymer structure of synthetic polymers is biodegraded under anoxic conditions. However, functional groups of ion exchangers and plasticizers in plastics are considered to be readily available and biodegradable. The greatest obstacle to biological degradation of synthetic polymers is depolymerisation to produce labile monomers. As energy is generally required for such breakdown, the chances of this process taking place outside the cells are very low. In so far as they are present, monomers are, in principle, anaerobically biodegradable. Thermodynamic considerations indicate that degradation of synthetic polymers under repository conditions is theoretically possible. However, the degradation of polystyrene is very close to thermodynamic equilibrium and the usable energy for microorganisms would barely be sufficient. Under high H2 partial pressures, it is predicted that there will be a thermodynamic inhibition of anaerobic degradation, as certain interim steps in degradation are endergonic. The starting conditions for microbial growth in a deep repository are unfavourable in terms of availability of water and prevailing pH values. Practically no known microorganisms can tolerate the combination of these conditions; most known

  16. Krebs Cycle Intermediates Protective against Oxidative Stress by Modulating the Level of Reactive Oxygen Species in Neuronal HT22 Cells

    Kenta Sawa

    2017-03-01

    Full Text Available Krebs cycle intermediates (KCIs are reported to function as energy substrates in mitochondria and to exert antioxidants effects on the brain. The present study was designed to identify which KCIs are effective neuroprotective compounds against oxidative stress in neuronal cells. Here we found that pyruvate, oxaloacetate, and α-ketoglutarate, but not lactate, citrate, iso-citrate, succinate, fumarate, or malate, protected HT22 cells against hydrogen peroxide-mediated toxicity. These three intermediates reduced the production of hydrogen peroxide-activated reactive oxygen species, measured in terms of 2′,7′-dichlorofluorescein diacetate fluorescence. In contrast, none of the KCIs—used at 1 mM—protected against cell death induced by high concentrations of glutamate—another type of oxidative stress-induced neuronal cell death. Because these protective KCIs did not have any toxic effects (at least up to 10 mM, they have potential use for therapeutic intervention against chronic neurodegenerative diseases.

  17. Experimental and modelling investigations of the biogeochemistry of gas production from low and intermediate level radioactive waste

    Small, Joe; Nykyri, Mikko; Helin, Mika; Hovi, Ulla; Sarlin, Tuija; Itaevaara, Merja

    2008-01-01

    The degradation of organic wastes and the corrosion of metallic wastes and steel containers in low and intermediate level radioactive waste (LLW/ILW) repositories are important processes that affect repository geochemistry and the speciation and transport of radionuclides. Gas is generated in association with these degradation processes and this has the potential to overpressure the repository, which can promote transport of groundwater and gas, and consequently radionuclide transport. Microbial activity plays an important role in organic degradation, corrosion and gas generation through the mediation of reduction-oxidation reactions. A large-scale gas generation experiment has been established at the LLW/ILW repository, Olkiluoto, Finland to examine gas generation from LLW in waste drums disposed of in the operational VLJ Repository (VLJ is a Finnish acronym which translates to 'reactor operating waste'). The experiment has monitored, for a period of 9 a, the rate and composition of gas generated, and the aqueous geochemistry and microbe populations present at various locations within the experiment. There is considerable heterogeneity within the experiment, such that pH is observed to vary from pH 5.5 to pH 10 between organic-rich waste and water associated with concrete. The heterogeneity results in competing anaerobic processes occurring together in the experiment but within different niches. Microbial activity initially dominant in organic waste has after 7 a reduced the alkalinity of the concrete influenced regions. The experiment has been modelled using a biogeochemical reaction-transport code (GRM) using a blind testing approach. Using independent data, the model was able to reproduce, within a factor of two, the rate of gas production. In addition, the model represented the main anaerobic microbial processes leading to methanogenesis and the observed spatial and temporal variations in aqueous and gaseous species. In order to model the experiment, its

  18. Use of low density lipoprotein particle number levels as an aid in statin treatment decisions for intermediate risk patients: a cost-effectiveness analysis.

    Shiffman, Dov; Arellano, Andre R; Caulfield, Michael P; Louie, Judy Z; Bare, Lance A; Devlin, James J; Melander, Olle

    2016-12-07

    The 2013 ACC/AHA guideline recommended either no statin therapy or moderate-intensity statin therapy (MST) for intermediate risk patients-those with 5-7.5% 10-year risk and without cardiovascular disease (CVD), hypercholesterolemia or diabetes. The guideline further suggested that the therapy choice be based on patient-clinician discussions of risks and benefits. Since low-density lipoprotein particle (LDL-P) levels were reported to be associated with CVD independently of traditional risk factors in intermediate and low risk patients, we investigated the cost-effectiveness of using LDL-P levels to identify intermediate risk patients likely to benefit from initiating or intensifying statin therapy. We evaluated 5 care strategies for intermediate risk patients. These included the strategies suggested by the guideline: no-statin therapy and MST. We compared each of these strategies to a related strategy that incorporated LDL-P testing. No-statin therapy was compared with the strategy of MST for those with high LDL-P levels and no statin therapy for all other patients (test-and-MST). MST was compared with the strategy of high-intensity statin therapy (HST) for those with high LDL-P levels and MST for all other patients (test-and-HST). We also evaluated the strategy of HST for all. Costs (payer perspective) and utilities were assessed over a 5-year time horizon in a Markov model of 100,000 hypothetical intermediate risk patients. HST dominated all other strategies, costing less and-despite causing 739 more cases of diabetes than did MST-resulting in more quality adjusted life-years (QALYs). For patient-clinician discussions that would otherwise lead to the MST strategy, we found the test-and-HST strategy reduced costs by $4.67 MM and resulted in 134 fewer CVD events and 115 additional QALYs. For patient-clinician discussions that would otherwise lead to no statin therapy, we found that the test-and-MST strategy reduced costs by $3.25 MM, resulted in 97 fewer CVD events

  19. Corrosion behaviour of steel rebars embedded in a concrete designed for the construction of an intermediate-level radioactive waste disposal facility

    Schulz F.M.

    2013-07-01

    Full Text Available The National Atomic Energy Commission of the Argentine Republic is developing a nuclear waste disposal management programme that contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The repository is based on the use of multiple, independent and redundant barriers. The major components are made in reinforced concrete so, the durability of these structures is an important aspect for the facility integrity. This work presents an investigation performed on an instrumented reinforced concrete prototype specifically designed for this purpose, to study the behaviour of an intermediate level radioactive waste disposal facility from the rebar corrosion point of view. The information obtained will be used for the final design of the facility in order to guarantee a service life more or equal than the foreseen durability for this type of facilities.

  20. Implications of long-term surface or near-surface storage of intermediate and low-level wastes in the UK

    Murray, N.; Vande Putte, D.; Ware, R.J.

    1986-02-01

    Various options for 200 year-long storage of all Low- and Intermediate-Level wastes generated to the year 2030 are considered. On-site storage and centralised storage have been examined and compared. The feasibility of storing some of the wastes in underground facilities that are convertible to repositories has been demonstrated, but it is shown that centralised, surface storage of wastes would be more economical. There appears to be little merit in storing Intermediate Level wastes in separate facilities that could be converted to repositories. Storage is shown to be more expensive than direct disposal, except if future costs are discounted by more than about 10%. With carefully designed stores and remote handling, the collective dose to operators could be limited to about 20-40 man Sv over the whole period of storage. (author)