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Sample records for chemical effects of nuclear transformations

  1. Chemical effects of nuclear transformations

    Energy Technology Data Exchange (ETDEWEB)

    Bulbulian, S

    1982-06-01

    A brief survey of the present state of knowledge on the chemical effects of nuclear transformations is presented. The recoil energy produced by these transformations in the nuclide is often sufficiently high to disrupt the chemical ligands between these particular atoms affected by the nuclear transformations, while the rest of their molecules. It also contains a discussion of the different annealing processes that produce the cancellation of the chemical change produced by the nuclear transformation.

  2. Chemical effects of nuclear transformations symposium in Prague

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1961-01-15

    The Symposium on Chemical Effects of Nuclear Transformations showed that interest in the subject matter is far from being exclusively academic. Though a large number of the papers dealt with theoretical aspects, it was felt that hot atom reactions provided a valuable means by which a large number of radioactive isotopes and labelled compounds could be prepared practically free from their inactive counterparts. Such so-called carrier-free preparations are in great demand for industrial, medical and scientific applications. Discussions showed that a detailed knowledge o: the characteristics of radiation damage was essential to the successful development of nuclear power Nuclear transformations in solids provide a method of generating such damage and at the same time leave radioactive products that permit the study of the subsequent repair. This technique permits studies a' levels of damage much below those that are necessary with the less sensitive purely physical procedures. A number of papers emphasized the theoretical importance of the insight which hot atom chemistry gives into the mechanism of reactions occurring at abnormal temperatures.

  3. Investigation of the chemical effects of nuclear transformations by Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    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.)

  4. Chemical Effects of Nuclear Transformations Vol. I. Proceedings of the Symposium on Chemical Effects Associated with Nuclear Reactions and Radioactive Transformations

    International Nuclear Information System (INIS)

    1965-01-01

    The study of the chemical changes consequent upon the nuclear transformation of an atom that is linked with other atoms in a molecule and surrounded by other similar or dissimilar molecules has intrigued chemists for a number of years. This interest is certainly not static but if anything is increasing. The main theme of this meeting was a discussion of the suggestions and theories that have been advanced to explain the wealth of experimental observations on the behaviour of atoms at energies and in situations not normally accessible in the laboratory. Though the subject has some practical implications in the preparation of radioisotopes, this was not an important consideration at this Symposium. The first Symposium on hot-atom chemistry organized by the Agency was held in Prague in October 1960. Comparison of the past and the present state of the subject shows that a greater variety and sophistication of techniques are now being applied as the simpler approaches used in the past have been shown to be inadequate. Progress has been made in the understanding of the simpler gas system, but in liquids and solids there is still much to clarify. It is also of interest that for the majority of the work reported in these Proceedings a reactor was the radiation source, and in this field much experimental work still remains to be done. The Symposium on Chemical Effects Associated with Nuclear Reactions and Radioactive Transformations was held from 7 to 11 December 1964 in Vienna, and was attended by 136 participants from 29 countries and 4 international organizations. It was organized by the International Atomic Energy Agency in co-operation with the Joint Commission on Applied Radioactivity. The publication of these Proceedings makes the content of the papers and discussion available to a wider audience than was possible at the meeting in Vienna

  5. Chemical consequences of nuclear transformations

    International Nuclear Information System (INIS)

    Collins, C.H.; Lancas, F.M.; Andrade, J.C. de; Collins, K.E.

    1979-01-01

    The recombination processes of chemical bonds in liquid phase, after being split by nuclear transformations, include hot and diffuse reactions. Both processes probably occur by different mechanisms. The direct substitution process as well as processes which involve atoms, ions or other fragments retained in 'cages' formed by surrounding molecules, are processes not sensitive to the presence of a sequestering agent. The diffuse reactions whose fragments escaped from the 'cage' involve reactions with any reactive species found in the medium. (Author) [pt

  6. Transformation of highly toxic chemicals factory for Fuqing nuclear power plant

    International Nuclear Information System (INIS)

    Wang Hongkai; Gao Yuan; Li Hua

    2014-01-01

    For the iodine adsorption tests of current M310 nuclear power plant, dimethyl sulfate is one of highly toxic chemical of national strict standard management, and the nation make strict control over toxic chemicals procurement, transportation, storage, management requirements. Since the appropriate toxic chemicals storage place was not considered in the design of M310 nuclear power plant, Fuqing nuclear power sites for storage of dimethyl sulfate implement technical transformation to meet and regulate the storage requirements for highly toxic chemical. This will lay the foundation for carrying out smoothly the relevant tests of nuclear power plant, and provide the reference for the use and construction of toxic chemicals reactor in the same type nuclear power plant. (authors)

  7. Nuclear transformations studies in selenium isotopes

    International Nuclear Information System (INIS)

    Lopez M, B.E.

    1976-01-01

    A compilation is made with regard to the chemical effects produced by nuclear transformations, such as the chemical effects of the beta decay and the chemical effects of the reaction (n,γ) in selenium radioisotopes. As a particular case the chemical effect of the isomeric transition of sup(81m)Se(VI) in potassium selenate crystals marked with radioactive selenium is studied experimentally and the method of adsorption in activated carbon is applied for the analytical separation of the traces of the nuclear isomer tetravalent sup(81b)Se(IV) of one fraction which contains the mixture of the selenium radioisotopes. (author)

  8. Primary processes initiated by nuclear transformations in solids

    International Nuclear Information System (INIS)

    Sano, Hirotoshi

    1975-01-01

    Primary processes of hot atom production initiated by nuclear transformation were discussed from past studies using Moessbauer spectroscopy. Many insulators (dielectric substances) showed various effect, such as abnormaly oxdized condition, following nuclear disintegration within the time duration of the life of Moessbauer nuclear excited state. Supposing these hot atom processes belonged to radiochemical processes, radiochemical characteristics of a certain chemical substance could be clarified by placing Moessbauer nuclide in the neighbourhood of the chemical substance to be studied. Chemical effects of disintegrated atom in the first and second composition, chemical substances produced in the surroundings of disintegrated atom, and environmental disturbance of disintegrated atom were studied and discussed. (Tsukamoto, Y.)

  9. Sustainable Transformation & Effective Competency Management Practices in Nuclear Organizations

    International Nuclear Information System (INIS)

    Gardelliano, S.

    2016-01-01

    Full text: Managing essential knowledge as a strategic organizational asset is a factor of upmost relevance in today’s nuclear organizations. The author considers evident that competencies are critical carriers of knowledge. As such the use of an appropriate competency model could be the most effective way to capture the present reservoir of explicit and tacit Knowledge of specific functions or organizational areas. Besides, we could use them for new or other redesigned functions or determine the needs of specific competencies for future positions. Therefore, appropriate competency models or systems have to be developed or updated in each nuclear organization since these are fundamental for managing more effectively and efficiently the present nuclear human capital and to forecast the evolving competence required in management, technical, scientific and safety areas to continuously ensure a highly competent nuclear workforce. On the other hand, competency based management models or systems would not achieve the expected results if they are not fully designed and integrated within the strategic organizational infrastructure of the related nuclear organization. This paper is expected to provide a wider view and practical reflections on organizational transformation issues and the benefits of using an integrative competency model in the nuclear industry. Particularly, the paper give an insight of an empiric model for strategic organizational transformation processes and integrative management practices, and on how to realign strategic issues with top management processes and build organizational capacity through effective competency based management for the sustainable transformation of nuclear organizations. (author

  10. Chemical effects associated to (n, γ) nuclear reactions in diluted aqueous solutions of liquid or frozen organic halogenides

    International Nuclear Information System (INIS)

    Bermudez Rodriguez, I.M.

    1985-09-01

    Chemical effects associated to nuclear transformation 37 Cl (n, γ) 38 Cl or 127 I (n, γ) 128 I in solid or liquid aqueous solutions of ethyl iodide, trichloro-ethylene, thyroxine or DDT irradiated in a nuclear reactor are studied. The retention of radiohalogen under its initial chemical shape decrease with solute concentration in liquid phase but is almost constant with solute dilution in the solid phase. Potential applications in neutron activation analysis evidencing halogenated molecules in irradiated media are discussed. 57 refs [fr

  11. Acquired experience resulting from transforming a chemical installation into a nuclear one

    Energy Technology Data Exchange (ETDEWEB)

    Zamfirache, M.; Stefan, L.; Bornea, A.; Stefanescu, I. [National Research and Development Institute for Cryogenics and Isotopic Technologies - ICIT, Uzinei (Romania)

    2015-03-15

    ICIT-Valcea has developed an experimental pilot-scale installation for tritium and deuterium separation. The main objective of this pilot was to demonstrate the water detritiation technology and to transfer this technology to the CANDU reactors of the Cernavoda nuclear power plant. The pilot-scale installation was initiated in 1992. The initial design and construction were performed similarly to chemical plants as the separation of isotopes was focused on only hydrogen and deuterium to assess feasibility. In a second phase we have begun to transform it into a nuclear facility with the aim of separating tritium. Moving to tritium separation has imposed a lot of changes. Changes consisted mainly of: -) re-design of the technological systems for nuclear material processing, applying specific codes and standards (ASME, Romanian nuclear specific pressure boundary prescriptions for code classification); -) design and implementation of new systems, classified as safety systems; -) re-design and implementation of command and control systems, complying with the requirements of reliability and maintenance required for the project promoted; -) revaluation of auxiliary systems (utilities, power supply); -) implementing radiation protection systems, including secondary barriers; -) implementing and maintaining environment operational program specific to the new nuclear plant; -) developing and conducting safety analyzes; and -) the production of specific documentation to obtain the necessary permits for construction, commissioning and operation of the plant.

  12. Chemical effects of nuclear transformations in metal permanganates

    International Nuclear Information System (INIS)

    Lee, Byung Hun; Kim, Bong Whan

    1986-01-01

    The chemical effects resulting from the capture of the thermal neutrons by manganese in different crystalline permanganates, that is, potassium permanganate,sodium permanganate, silver permanganate, barium permanganate and ammonium permanganate, have been investigated. The distribution of radioactive manganese formed has been determined by using different absorbents and ion-exchangers, that is,manganese dioxide, alumina, Zeolite A-3, Kaolinite and Dowex-50. The distribution of radioactive manganese in various adsorbents and ion-exchangers has almost similar result for each permanganate. The affinity for radioactive manganous ion is greatest for Dewex-50. A significant increase of retention is shown through the thermal annealing and the retention depends on the first ionization potential of metal ion in permanganates. (Author)

  13. Spin coherence transfer in chemical transformations monitoredNMR

    Energy Technology Data Exchange (ETDEWEB)

    Anwar, Sabieh M.; Hilty, Christian; Chu, Chester; Bouchard,Louis-S.; Pierce, Kimberly L.; Pines, Alexander

    2006-07-31

    We demonstrate the use of micro-scale nuclear magneticresonance (NMR) for studying the transfer of spin coherence innon-equilibrium chemical processes, using spatially separated NMRencoding and detection coils. As an example, we provide the map ofchemical shift correlations for the amino acid alanine as it transitionsfrom the zwitterionic to the anionic form. Our method is unique in thesense that it allows us to track the chemical migration of encodednuclear spins during the course of chemical transformations.

  14. Chemical Transformation Simulator

    Science.gov (United States)

    The Chemical Transformation Simulator (CTS) is a web-based, high-throughput screening tool that automates the calculation and collection of physicochemical properties for an organic chemical of interest and its predicted products resulting from transformations in environmental sy...

  15. In vitro transformation: interactions of chemical carcinogens and radiation

    International Nuclear Information System (INIS)

    DiPaolo, J.A.

    1976-01-01

    The development of reproducible quantitative in vitro procedures resulting in neoplastic transformation of mammalian cells has made possible the separation of events related to the process leading to transformation from secondary events that interfere with the early recognition of transformation. The use of chemical carcinogens on Syrian hamster cell strains results in a dose-response relation consistent with a Poisson distribution, indicating that the transformation phenomenon is inductive. In some circumstances, the joint action or interaction of chemical carcinogens with other agents results in an increased incidence of transformation. The pretreatment of Syrian hamster cells with ionizing radiation (250 R) or alkylating chemicals enhances the frequency of transformation on a cell or colony basis ordinarily obtained with known chemical carcinogens. Pretreatment with non-ionizing irradiation (uv, 254 nm) did not have a similar effect. The two types of irradiation and the alkylating agents reduced the cloning efficiency of the cells. X ray alone produced no transformation; the alkylating chemicals produced transformations infrequently, whereas uv produced a significant number of transformations. The number of transformations associated with uv is increased by pretreatment of the cells by x-irradiation. The enhancement of transformation by x-ray or x-ray-type agents appears to be independent of the type of second carcinogen used

  16. Delayed effects of nuclear and chemical weapons in man

    International Nuclear Information System (INIS)

    Dienstbier, Z.

    1984-01-01

    Delayed radiation effects are discussed of the use of nuclear and chemical weapons (defoliants and herbicides). Attention is drawn to the development of delayed malignities in exposed subjects and their pathophysiologic causes are explained. The only prevention of these effects is to prohibit the use of weapons of mass destruction. (author)

  17. Fourier transform nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Geick, R.

    1981-01-01

    This review starts with the basic principles of resonance phenomena in physical systems. Especially, the connection is shown between the properties of these systems and Fourier transforms. Next, we discuss the principles of nuclear magnetic resonance. Starting from the general properties of physical systems showing resonance phenomena and from the special properties of nuclear spin systems, the main part of this paper reviews pulse and Fourier methods in nuclear magnetic resonance. Among pulse methods, an introduction will be given to spin echoes, and, apart from the principle of Fourier transform nuclear magnetic resonance, an introduction to the technical problems of this method, e.g. resolution in the frequency domain, aliasing, phase and intensity errors, stationary state of the spin systems for repetitive measurements, proton decoupling, and application of Fourier methods to systems in a nonequilibrium state. The last section is devoted to special applications of Fourier methods and recent developments, e.g. measurement of relaxation times, solvent peak suppression, 'rapid scan'-method, methods for suppressing the effects of dipolar coupling in solids, two-dimensional Fourier transform nuclear magnetic resonance, and spin mapping or zeugmatography. (author)

  18. Aging of safety class 1E transformers in safety systems of nuclear power plants

    International Nuclear Information System (INIS)

    Roberts, E.W.; Edson, J.L.; Udy, A.C.

    1996-02-01

    This report discusses aging effects on safety-related power transformers in nuclear power plants. It also evaluates maintenance, testing, and monitoring practices with respect to their effectiveness in detecting and mitigating the effects of aging. The study follows the US Nuclear Regulatory Commission's (NRC's) Nuclear Plant-Aging Research approach. It investigates the materials used in transformer construction, identifies stressors and aging mechanisms, presents operating and testing experience with aging effects, analyzes transformer failure events reported in various databases, and evaluates maintenance practices. Databases maintained by the nuclear industry were analyzed to evaluate the effects of aging on the operation of nuclear power plants

  19. Aging of safety class 1E transformers in safety systems of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, E.W.; Edson, J.L.; Udy, A.C. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)

    1996-02-01

    This report discusses aging effects on safety-related power transformers in nuclear power plants. It also evaluates maintenance, testing, and monitoring practices with respect to their effectiveness in detecting and mitigating the effects of aging. The study follows the US Nuclear Regulatory Commission`s (NRC`s) Nuclear Plant-Aging Research approach. It investigates the materials used in transformer construction, identifies stressors and aging mechanisms, presents operating and testing experience with aging effects, analyzes transformer failure events reported in various databases, and evaluates maintenance practices. Databases maintained by the nuclear industry were analyzed to evaluate the effects of aging on the operation of nuclear power plants.

  20. Microbial transformations of radionuclides released from nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    Francis, A.J.

    2007-01-01

    Microorganisms can affect the stability and mobility of the actinides U, Pu, Cm, Am, Np, and the fission products Tc, I, Cs, Sr, released from nuclear fuel reprocessing plants. Under appropriate conditions, microorganisms can alter the chemical speciation, solubility and sorption properties and thus could increase or decrease the concentrations of radionuclides in solution and the bioavailability. Dissolution or immobilization of radionuclides is brought about by direct enzymatic action or indirect non-enzymatic action of microorganisms. Although the physical, chemical, and geochemical processes affecting dissolution, precipitation, and mobilization of radionuclides have been investigated, we have only limited information on the effects of microbial processes. The mechanisms of microbial transformations of the major and minor actinides and the fission products under aerobic and anaerobic conditions in the presence of electron donors and acceptors are reviewed. (author)

  1. Some radiation chemical aspects of nuclear engineering

    International Nuclear Information System (INIS)

    Pikaev, A.K.; Kabakchi, S.A.; Egorov, G.F.

    1988-01-01

    Some radiation chemical aspects of nuclear engineering are discussed (predominantly on the base of the works performed in the Soviet Union). The data on the influence of temperature within the range of 0-300 0 C on the yields of water radiolysis products are considered. The results obtained from the study of reactivity of actinide ions towards inorganic free radicals in acid aqueous solutions are summarized. The information on composition and properties of the products of radiolytic transformations of different extragents and diluents and on their influence on the behaviour of extraction systems during processing of irradiated nuclear fuel is presented. (author)

  2. Chemical effects of /sup 32/P recoil atom

    Energy Technology Data Exchange (ETDEWEB)

    Matsuura, N [Tokyo Univ. (Japan). Coll. of General Education

    1975-06-01

    Szilard-Chalmers' effect of /sup 32/P were reviewed. The concentration method using Szilard-Chalmers' effect in production of radioisotope, circumstances such as exposure time in an atomic pile, states of target substances and the yields by them were discussed. Many kinds of chemical effects, such as chemical effects of /sup 32/P recoil atom in phosphorated glass, studies of the effect of adducts, the threshold of ..gamma..-ray effect, the oxidation number of /sup 32/P in phosphorated glass by exposure time in the pile and the labelling position of /sup 32/P, are associated with caryotransformation (nuclear transformation) by environmental factors. The abovementioned articles were explained concerning /sup 32/P.

  3. Chemical Graph Transformation with Stereo-Information

    DEFF Research Database (Denmark)

    Andersen, Jakob Lykke; Flamm, Christoph; Merkle, Daniel

    2017-01-01

    Double Pushout graph transformation naturally facilitates the modelling of chemical reactions: labelled undirected graphs model molecules and direct derivations model chemical reactions. However, the most straightforward modelling approach ignores the relative placement of atoms and their neighbo......Double Pushout graph transformation naturally facilitates the modelling of chemical reactions: labelled undirected graphs model molecules and direct derivations model chemical reactions. However, the most straightforward modelling approach ignores the relative placement of atoms...... and their neighbours in space. Stereoisomers of chemical compounds thus cannot be distinguished, even though their chemical activity may differ substantially. In this contribution we propose an extended chemical graph transformation system with attributes that encode information about local geometry. The modelling...... of graph transformation, but we here propose a framework that also allows for partially specified stereoinformation. While there are several stereochemical configurations to be considered, we focus here on the tetrahedral molecular shape, and suggest general principles for how to treat all other chemically...

  4. Nuclear, biological and chemical warfare. Part I: Medical aspects of nuclear warfare.

    Science.gov (United States)

    Kasthuri, A S; Pradhan, A B; Dham, S K; Bhalla, I P; Paul, J S

    1990-04-01

    Casualties in earlier wars were due much more to diseases than to weapons. Mention has been made in history of the use of biological agents in warfare, to deny the enemy food and water and to cause disease. In the first world war chemical agents were used to cause mass casualties. Nuclear weapons were introduced in the second world war. Several countries are now involved in developing nuclear, biological and chemical weapon systems, for the mass annihilation of human beings, animals and plants, and to destroy the economy of their enemies. Recently, natural calamities and accidents in nuclear, chemical and biological laboratories and industries have caused mass instantaneous deaths in civilian population. The effects of future wars will not be restricted to uniformed persons. It is time that physicians become aware of the destructive potential of these weapons. Awareness, immediate protective measures and first aid will save a large number of persons. This series of articles will outline the medical aspects of nuclear, biological and chemical weapon systems in three parts. Part I will deal with the biological effects of a nuclear explosion. The short and long term effects due to blast, heat and associated radiation are highlighted. In Part II, the role of biological agents which cause commoner or new disease patterns is mentioned. Some of the accidents from biological warfare laboratories are a testimony to its potential deleterious effects. Part III deals with medical aspects of chemical warfare agents, which in view of their mass effects can overwhelm the existing medical resources, both civilian and military.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Bonding pathways of high-pressure chemical transformations

    International Nuclear Information System (INIS)

    Hu Anguang; Zhang Fan

    2013-01-01

    A three-stage bonding pathway towards high-pressure chemical transformations from molecular precursors or intermediate states has been identified by first-principles simulations. With the evolution of principal stress tensor components in the response of chemical bonding to compressive loading, the three stages can be defined as the van der Waals bonding destruction, a bond breaking and forming reaction, and equilibrium of new bonds. The three-stage bonding pathway leads to the establishment of a fundamental principle of chemical bonding under compression. It reveals that during high-pressure chemical transformation, electrons moving away from functional groups follow anti-addition, collision-free paths to form new bonds in counteracting the local stress confinement. In applying this principle, a large number of molecular precursors were identified for high-pressure chemical transformations, resulting in new materials. (fast track communication)

  6. Nuclear chemical engineering

    International Nuclear Information System (INIS)

    Lee, Geon Jae; Shin, Young Jun

    1989-08-01

    The contents of this book are introduction of chemical engineering and related chemistry on an atomic reactor, foundation of the chemistry nuclear chemical engineering, theory on nuclear engineering, the cycle of uranium and nuclear fuel, a product of nuclear division, nuclear reprocessing, management of spent fuel separation of radioisotope, materials of an atomic reactor, technology and chemistry related water in atomic reactors and utilization of radioisotope and radiation. This book has the exercises and reference books for the each chapter.

  7. Effect of chemical ordering annealing on martensitic transformation and superelasticity in polycrystalline Ni–Mn–Ga microwires

    Energy Technology Data Exchange (ETDEWEB)

    Qian, M.F. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Advanced Composites Centre for Innovation and Science (ACCIS), University of Bristol, Queen’s Building, University Walk, Bristol BS8 1TR (United Kingdom); Zhang, X.X., E-mail: xxzhang@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Wei, L.S.; Geng, L. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Peng, H.X., E-mail: hxpengwork@zju.edu.cn [Institute for Composites Science Innovation (InCSI), School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China)

    2015-10-05

    Highlights: • Chemical ordering annealing on Ni–Mn–Ga microwires was found to reduce the defect density and internal stress. • Chemical ordering annealing on Ni–Mn–Ga microwires was found to increase the MT temperatures, Curie point and saturation magnetization. • Chemical ordering annealing on Ni–Mn–Ga microwires was found to decrease the SIM stress and improve the superelastic reversibility. • Chemical ordering annealing on Ni–Mn–Ga microwires was found to weaken the temperature dependences of the superelastic stresses. - Abstract: Polycrystalline Ni–Mn–Ga microwires of diameter 30–80 μm were prepared by melt-extraction technique on a large scale. The rapidly solidified microwires exhibit a fairly high ductility and excellent shape memory property. Here, with the aim to reduce the defect density, internal stress and compositional inhomogeneity in the as-extracted microwires, a stepwise chemical ordering annealing heat treatment was carried out and the effect of annealing on martensitic transformation, magnetic properties and superelastic behavior were investigated. The results indicate that annealing increase the transformation temperature and decrease the transformation hysteresis. These are related to composition homogenization, increase of atomic ordering and decrease in internal stress and defects. During mechanical tests, the stress-induced martensite (SIM) formation took place at a much lower stress after annealing treatment. The annealed microwires also demonstrate a lower superelastic hysteresis and a higher recovery rate compared to the as-extracted microwires. The temperature dependence of SIM stress is weaker after annealing, which is related to the enthalpy change (ΔH) and phase transformation temperature change according to the Clausius–Clapeyron relation.

  8. Understanding mechanisms of solid-state phase transformations by probing nuclear materials

    Science.gov (United States)

    Banerjee, Srikumar; Donthula, Harish

    2018-04-01

    In this review a few examples will be cited to illustrate that a study on a specific nuclear material sometimes lead to a better understanding of scientific phenomena of broader interests. Zirconium alloys offer some unique opportunities in addressing fundamental issues such as (i) distinctive features between displacive and diffusional transformations, (ii) characteristics of shuffle and shear dominated displacive transformations and (iii) nature of mixed-mode transformations. Whether a transformation is of first or higher order?" is often raised while classifying it. There are rare examples, such as Ni-Mo alloys, in which during early stages of ordering the system experiences tendencies for both first order and second order transitions. Studies on the order-disorder transitions under a radiation environment have established the pathway for the evolution of ordering. These studies have also identified the temperature range over which the chemically ordered state remains stable in steady state under radiation.

  9. Chemical effects of nuclear transformations in molybdenum complexes

    International Nuclear Information System (INIS)

    Millan S, S.A.

    1977-01-01

    The Szilard-Chalmers effect was studied in the complexes: tetraacetatedimolybdenum(II), tetrabenzoatedimolybdenum(II), benzenetricarbonylmolybdenym(0). The results we obtained in the measurement of the Szilard-Chalmers effect on the studied complexes imply some influence of the structure in the molecular fragmentation, or the conservation of the links molybdenum-ligands. (author)

  10. Allocation of fossil and nuclear fuels. Heat production from chemically and physically bound energy

    International Nuclear Information System (INIS)

    Wagner, U.

    2008-01-01

    The first part of the book presents the broad field of allocation, transformation, transport and distribution of the most important energy carriers in the modern power industry. The following chapters cover solid fossil fuel, liquid fuel, gaseous fuel and nuclear fuel. The final chapters concern the heat production from chemically and physically bound energy, including elementary analysis, combustion calculations, energy balance considerations in fossil fuel fired systems, and fundamentals of nuclear physics

  11. Comparison of the effects in the rock mass of large-scale chemical and nuclear explosions. Final technical report, June 9, 1994--October 9, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Spivak, A.A.

    1995-04-01

    It was found that in the first approximation the mechanical effect of underground nuclear explosion is analogous to the effect of chemical explosion. Really qualitative analysis shows that accompanying mechanical effects of nuclear and chemical explosions are the same: in the both cases explosion consequences are characterized by formation of the camouplet cavity (crater after explosion near free surface), destruction of the rock massif near explosion centre, creation of the stress wave, which forms seismoexplosive effect a long distance from explosion epicentre. Qualitative likeness of underground nuclear explosions and chemical explosions is the base of modelling the mechanical effects of the underground nuclear explosion. In this paper we`ll compare two explosions: nuclear (15-04-84) and chemical (27.06.95) with large power. These explosions were realized at the same geological conditions at Degelen test area, which is a part of the Semipalatinsk Test Site. In the case of the nuclear explosion, the charge was disposed in the face of the deep horizontal gallery. The charge of the chemical explosion was a semisphere from explosives at the rock massif surface. In the both case rock massif behavior after explosions was investigated at underground conditions (in the case of chemical explosion -- in the long underground excavation from explosion epicentre). Mechanical effects from the nuclear and chemical explosions were investigated with the same methods. The changes in geological medium after a large-scale explosive actions will be analyzed in detail too. Investigations of the influence of tectonic energy on the mechanical effects after underground nuclear, explosions represents the main interest. In this paper we`ll discuss this question on the data from underground nuclear explosion, realized 08.09.89 in the deep well at the Balapan test area, at the Semipalatinsk Test Site.

  12. Transport of chemically bonded nuclear energy in a closed cycle with special consideration to energy disconnection

    International Nuclear Information System (INIS)

    Ossami, S.

    1976-01-01

    The article describes the utilisation of nuclear energy in the form of 'nuclear long-distance energy'. Heat produced by nuclear fission is bonded to a reversible chemical reaction (cracking gas) which release the heat again at the place of comsumption by catalytic transformation. The article deals in particular with the process of methane cracking/methanisation, the disconnection of the energy (heat) by the methanisation process and the decisive role of the methanisation catalyzers. (orig.) [de

  13. Applications of wavelet transforms for nuclear power plant signal analysis

    International Nuclear Information System (INIS)

    Seker, S.; Turkcan, E.; Upadhyaya, B.R.; Erbay, A.S.

    1998-01-01

    The safety of Nuclear Power Plants (NPPs) may be enhanced by the timely processing of information derived from multiple process signals from NPPs. The most widely used technique in signal analysis applications is the Fourier transform in the frequency domain to generate power spectral densities (PSD). However, the Fourier transform is global in nature and will obscure any non-stationary signal feature. Lately, a powerful technique called the Wavelet Transform, has been developed. This transform uses certain basis functions for representing the data in an effective manner, with capability for sub-band analysis and providing time-frequency localization as needed. This paper presents a brief overview of wavelets applied to the nuclear industry for signal processing and plant monitoring. The basic theory of Wavelets is also summarized. In order to illustrate the application of wavelet transforms data were acquired from the operating nuclear power plant Borssele in the Netherlands. The experimental data consist of various signals in the power plant and are selected from a stationary power operation. Their frequency characteristics and the mutual relations were investigated using MATLAB signal processing and wavelet toolbox for computing their PSDs and coherence functions by multi-resolution analysis. The results indicate that the sub-band PSD matches with the original signal PSD and enhances the estimation of coherence functions. The Wavelet analysis demonstrates the feasibility of application to stationary signals to provide better estimates in the frequency band of interest as compared to the classical FFT approach. (author)

  14. Development of stable marker-free nuclear transformation strategy ...

    African Journals Online (AJOL)

    Development of stable marker-free nuclear transformation strategy in the green microalga Chlorella vulgaris. ... into Chlorella by electroporation has very low stability and it is hard to screen the transformants without antibiotic marker genes.

  15. Chemical risks from nuclear waste repositories

    International Nuclear Information System (INIS)

    Persson, L.

    1988-01-01

    Studies concerning the chemical risks of nuclear waste are reviewed. The radiological toxicity of the material is of primary concern but the potential nonradiological toxicity should not be overlooked as the chemotoxic substances may reach the biosphere from a nuclear waste repository. In the report is concluded that the possible chemotoxic effects of a repository for nuclear waste should be studied as a part of the formal risk assessment of the disposal concept. (author)

  16. Effect of nuclear radiation on the electrical properties of chemical double layer capacitors

    International Nuclear Information System (INIS)

    Laghari, J.R.; Hammoud, A.N.

    1990-01-01

    The effects of nuclear radiation on the electrical properties of chemical double layer capacitors are determined. The capacitors were irradiated in a 2-MW nuclear reactor to different fluence levels. The exposure rate was 2.2 x 10 10 n/cm 2 · s of thermal neutrons, 9.52 x 10 8 n/cm 2 · s of fast neutrons (> 2 MeV), and 1.47 x 10 6 rad/h of gamma radiation. The properties measured during and after irradiation included the capacitance, equivalent series resistance, and open-circuit voltage. The post-irradiation effect on the leakage current was also determined. It was found that while the capacitance increased during irradiation, the equivalent series resistance and the open-circuit voltage decreased slightly during irradiation. Changes in these properties were not permanent s was evident from post-irradiation measurements. The leakage current did not show any significant change with radiation. The results indicate that chemical double layer capacitors can be suitably used as backup power source in electronic equipment operating in a radiation environment with total fluences up to 4.05 x 10 14 n/cm 2

  17. Nuclear industry - challenges in chemical engineering

    International Nuclear Information System (INIS)

    Sen, S.; Sunder Rajan, N.S.; Balu, K.; Garg, R.K.; Murthy, L.G.K.; Ramani, M.P.S.; Rao, M.K.; Sadhukhan, H.K.; Venkat Raj, V.

    1978-01-01

    As chemical engineering processes and operations are closely involved in many areas of nuclear industry, the chemical engineer has a vital role to play in its growth and development. An account of the major achievements of the Indian chemical engineers in this field is given with view of impressing upon the faculty members of the Indian universities the need for taking appropriate steps to prepare chemical engineers suitable for nuclear industry. Some of the major achievements of the Indian chemical engineers in this field are : (1) separation of useful minerals from beach sand, (2) preparation of thorium nitrate of nuclear purity from monazite, (3) processing of zircon sand to obtain nuclear grade zirconium and its separation from hafnium to obtain zirconium metal sponge, (4) recovery of uranium from copper tailings, (5) economic recovery of nuclear grade uranium from low grade uranium ores found in India, (6) fuel reprocessing, (7) chemical processing of both low and high level radioactive wastes. (M.G.B.)

  18. Nuclear Weapons Enterprise Transformation - A Sustainable Approach

    International Nuclear Information System (INIS)

    O'Brien, K H

    2005-01-01

    Nuclear weapons play an essential role in United States (U.S.) National Security Policy and a succession of official reviews has concluded that nuclear weapons will continue to have a role for the foreseeable future. Under the evolving U.S. government policy, it is clear that role will be quite different from what it was during the Cold War. The nuclear-weapons stockpile as well as the nuclear-weapons enterprise needs to continue to change to reflect this evolving role. Stockpile reductions in the early 1990s and the Stockpile Stewardship Program (SSP), established after the cessation of nuclear testing in 1992, began this process of change. Further evolution is needed to address changing security environments, to enable further reductions in the number of stockpiled weapons, and to create a nuclear enterprise that is cost effective and sustainable for the long term. The SSP has successfully maintained the U.S. nuclear stockpile for more than a decade, since the end of nuclear testing. Current plans foresee maintaining warheads produced in the 1980s until about 2040. These warheads continue to age and they are expensive to refurbish. The current Life Extension Program plans for these legacy warheads are straining both the nuclear-weapons production and certification infrastructure making it difficult to respond rapidly to problems or changes in requirements. Furthermore, refurbishing and preserving Cold-War-era nuclear weapons requires refurbishing and preserving an infrastructure geared to support old technology. Stockpile Stewardship could continue this refurbishment approach, but an alternative approach could be considered that is more focused on sustainable technologies, and developing a more responsive nuclear weapons infrastructure. Guided by what we have learned from SSP during the last decade, the stewardship program can be evolved to address this increasing challenge using its computational and experimental tools and capabilities. This approach must start

  19. Application of Rader transforms to the analysis of nuclear spectral data

    International Nuclear Information System (INIS)

    Kekre, H.B.; Madan, V.K.; Bairi, B.R.

    1988-01-01

    This paper describes a Rader transform method using a special arithmetic for the processing of nuclear spectral data. Rader transforms offer impressive computational savings vis-a-vis Fourier transform methods. Rader transforms require only integer additions and word shifts but no multiplications while Fourier transforms require complex arithmetic operations. Moreover, use of Rader transforms gives exact computations without any roundoff errors and does not require storage of basis functions. They are 'the best transforms' for computer processing of nuclear spectral data. Rader transforms using a Fermat prime 65 537 have been applied to deconvolve observed spectral data using a special filter function. A uniform improvement in resolution of 45% has been observed both in single and double spectrallines. A FORTRAN program GAMRAD is written to deconvolve spectral data using the special filter function. (orig.)

  20. Nuclear weapons and conflict transformation: the case of India-Pakistan. - Pbk ed.

    NARCIS (Netherlands)

    Khan, S.

    2010-01-01

    Introduction Part 1: Theory 1. Studies on Conflict Transformation 2. Scholarship on Ramifications of Nuclear Weapons Acquisition 3. Elucidating Conflict Transformation with Nuclear Weapons Part 2: The India-Pakistan Protracted Conflict 4. Life of the Protracted Conflict 5. Introduction of Nuclear

  1. Thermodynamics of nuclear track chemical etching

    Science.gov (United States)

    Rana, Mukhtar Ahmed

    2018-05-01

    This is a brief paper with new and useful scientific information on nuclear track chemical etching. Nuclear track etching is described here by using basic concepts of thermodynamics. Enthalpy, entropy and free energy parameters are considered for the nuclear track etching. The free energy of etching is determined using etching experiments of fission fragment tracks in CR-39. Relationship between the free energy and the etching temperature is explored and is found to be approximately linear. The above relationship is discussed. A simple enthalpy-entropy model of chemical etching is presented. Experimental and computational results presented here are of fundamental interest in nuclear track detection methodology.

  2. Trend analyses of transformer problems in the U.S. nuclear power plants

    International Nuclear Information System (INIS)

    Shimada, Yoshio

    2009-01-01

    Up to 2007, the authors have conducted the trend analyses of trouble events related to main generators, emergency diesel generators, breakers and motors, which are more likely to cause problems than other electric equipments in nuclear power plants. The frequency of trouble events in transformers in domestic nuclear power plants at present is approximately one third of the publicly reported cases in the U.S. However, as the situation of maintenance in Japan in the future will become similar to those in the U.S. if the operating period is extended or the maintenance method is to be shifted from preventive maintenance to condition based maintenance, there is a concern that the frequency of transformer events in Japan will increase in Japan, also. Thus, trend analyses were conducted on transformers events which had not been subject to such analyses, from among electrical equipments which are likely to cause problems. The trend analyses were performed on 23 transformer events which had occurred in the U.S. nuclear power plants in five years from 2003 through 2007 among events reported in the Licensee Event Reports (LERs: event reports submitted to NRC by U.S. nuclear power plants) which have been registered in the nuclear information database of the Institute of Nuclear Safety System, Incorporated's (INSS), as well as 8 events registered in the Nuclear Information Archives (NUCIA), which had occurred in domestic nuclear power plants in five from 2003 through 2007. Lessons learned from the trend analyses of the transformer trouble events in the U.S. revealed that for transformers in general, the maintenance management of tap changers is important, while for the main transformers which are most likely to cause problems, it is vital to prevent the deterioration of insulation and insulating oil. (author)

  3. Cumulative and competitive effects of chemical elements on nuclear glass alteration

    International Nuclear Information System (INIS)

    Arena, Helene

    2016-01-01

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

  4. Nuclear research center transformation experience

    International Nuclear Information System (INIS)

    Diaz, J. L.; Jimenez, J. M.

    2001-01-01

    As consequence of the changes in the energy polities of each countries in the 80th. many of the Nuclear Research Centres suffered a transformation (more of less deep) in other Research and Development Centres with a wider spectrum that the exclusively nuclear one. This year is the 50 anniversary of the Spanish Centre of Nuclear Research-Junta de Energia Nuclear.The JEN the same as other suffered a deep renovation to become the CIEMAT Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (Research Centre for Energy, Environment and Technology). This paper is focussed on the evolution of JEN to CIEMAT besides analysing the reach of this re-foundation considering the political reasons and technical aspect that justified it and the laws in those it is based on. (Author)

  5. Study of kinetics and mechanism of diazo compound reactions using nuclear chemical polarization

    International Nuclear Information System (INIS)

    Gragerov, I.P.; Levit, A.F.; Kiprianova, L.A.; Buchachenko, A.L.; Sterleva, T.G.

    1975-01-01

    It has been established that at the rate-determining steps of the radical reactions in which aniline interacts with isoamyl nitrite and substituted diazo salts interact with sodium methylate, tertiary fatty amines, or phosphinic acid, no transfer of a single electron occurs. The processes of single electron transfer do not seem to play a decisive role in the kinetics of most transformations of diazo compounds. Chemical nuclear polarization is shown to be suitable for kinetic studies of fast radical processes

  6. Aerosol simulation including chemical and nuclear reactions

    International Nuclear Information System (INIS)

    Marwil, E.S.; Lemmon, E.C.

    1985-01-01

    The numerical simulation of aerosol transport, including the effects of chemical and nuclear reactions presents a challenging dynamic accounting problem. Particles of different sizes agglomerate and settle out due to various mechanisms, such as diffusion, diffusiophoresis, thermophoresis, gravitational settling, turbulent acceleration, and centrifugal acceleration. Particles also change size, due to the condensation and evaporation of materials on the particle. Heterogeneous chemical reactions occur at the interface between a particle and the suspending medium, or a surface and the gas in the aerosol. Homogeneous chemical reactions occur within the aersol suspending medium, within a particle, and on a surface. These reactions may include a phase change. Nuclear reactions occur in all locations. These spontaneous transmutations from one element form to another occur at greatly varying rates and may result in phase or chemical changes which complicate the accounting process. This paper presents an approach for inclusion of these effects on the transport of aerosols. The accounting system is very complex and results in a large set of stiff ordinary differential equations (ODEs). The techniques for numerical solution of these ODEs require special attention to achieve their solution in an efficient and affordable manner. 4 refs

  7. Chemical nuclear polarization effects in photoreactions of 1,4-diazabicyclo[2.2.2]octane with carbonyl-containing compounds

    Science.gov (United States)

    Porkhun, V. I.; Rakhimov, A. I.

    2012-11-01

    Elementary acts of the photoreaction of diamine with 2,6-diphenyl- p-benzoquinone are determined from the effects of chemical nuclear polarization effects. Hydrogen atom transfer is shown to occur in two stages with the participation of a radical ion pair.

  8. Fourier transform infrared spectra applications to chemical systems

    CERN Document Server

    Ferraro, John R

    1978-01-01

    Fourier Transform Infrared Spectroscopy: Applications to Chemical Systems presents the chemical applications of the Fourier transform interferometry (FT-IR).The book contains discussions on the applications of FT-IR in the fields of chromatography FT-IR, polymers and biological macromolecules, emission spectroscopy, matrix isolation, high-pressure interferometry, and far infrared interferometry. The final chapter is devoted to the presentation of the use of FT-IR in solving national technical problems such as air pollution, space exploration, and energy related subjects.Researc

  9. PCB transformer fires: the risk in nuclear power plants

    International Nuclear Information System (INIS)

    Blackmon, K.

    1988-01-01

    It is estimated that 1/2 of the present nuclear power plants operate with PCB-filled transformer equipment. In an attempt to obtain better estimates of clean-up costs in a nuclear power plant under reasonable-loss scenarios, a study was commissioned. This study was a joint venture between Blackmon-Mooring Steamatic Technologies, Inc., (BMS-TECH) and M and M Protection Consultants. This joint study was conducted at a typical pressurized-water reactor plant consisting of two 1000-MW units. Three specific scenarios were selected and analyzed for this typical power plant. These scenarios were: (1) an electrical failure of a transformer in an isolated switch gear room; (2) a transformer exposed to a 55-gallon transient combustion oil fire in the auxiliary building; and (3) a PCB transformer involved in a major turbine lube fire in the turbine building. Based on results of this study, the insurance carriers for this industry implemented an adjustment in their rate structures for nuclear power plants that have PCB equipment

  10. Chemical characterization of nuclear fuel materials

    International Nuclear Information System (INIS)

    Ramakumar, K.L.

    2011-01-01

    India is fabricating nuclear fuels for various types of reactors, for example, (U-Pu) MOX fuel of varying Pu content for boiling water reactors (BWRs), pressurized heavy water reactors (PHWRs), prototype fast breeder reactors (PFBRs), (U-Pu) carbide fuel fast breeder test reactor (FBTR), and U-based fuels for research reactors. Nuclear fuel being the heart of the reactor, its chemical and physical characterisation is an important component of this design. Both the fuel materials and finished fuel products are to be characterised for this purpose. Quality control (both chemical and physical) provides a means to ensure that the quality of the fabricated fuel conforms to the specifications for the fuel laid down by the fuel designer. Chemical specifications are worked out for the major and minor constituents which affect the fuel properties and hence its performance under conditions prevailing in an operating reactor. Each fuel batch has to be subjected to comprehensive chemical quality control for trace constituents, stoichiometry and isotopic composition. A number of advanced process and quality control steps are required to ensure the quality of the fuels. Further more, in the case of Pu-based fuels, it is necessary to extract maximum quality data by employing different evaluation techniques which would result in minimum scrap/waste generation of valuable plutonium. The task of quality control during fabrication of nuclear fuels of various types is both challenging and difficult. The underlying philosophy is total quality control of the fuel by proper mix of process and quality control steps at various stages of fuel manufacture starting from the feed materials. It is also desirable to adapt more than one analytical technique to increase the confidence and reliability of the quality data generated. This is all the most required when certified reference materials are not available. In addition, the adaptation of non-destructive techniques in the chemical quality

  11. Nuclear and conventional energy transformation

    International Nuclear Information System (INIS)

    Schikarski, W.

    1979-03-01

    Atmospheric pollution from fossil fuel- and nuclear power plants have been compared. SO 2 is the substance chosen from coal- and oil fuel power plants. Measured values for chemical pollution are at levels 10 times, and radioactive pollution near to nuclear power plants, 10.000 times, below that which would cause damage to health. (A.R.H.) [pt

  12. Nuclear and chemical data

    Energy Technology Data Exchange (ETDEWEB)

    De Regge, P.

    1978-12-15

    The neutron fission yield and other nuclear and chemical data of interest to the nuclear applications of mass spectrometry (mainly in the field of burnup determination) are examined. The performance of those determinations and the achievable accuracy should match the needs of the users of the data produced. 3 figures, 2 tables. (RWR)

  13. Neutron albedo effects of underground nuclear explosion

    International Nuclear Information System (INIS)

    Yang Bo; Ying Yangjun; Li Jinhong; Bai Yun

    2013-01-01

    The neutron field distribution is affected by the surrounding medium in the underground nuclear explosion. It will influence the radiation chemical diagnosis. By Monte Carlo simulation, the fuel burnup induced by device and neutron albedo was calculated. The analysis method of albedo effect on radiation chemical diagnosis result under special environment was proposed. Neutron albedo should be considered when capture reaction burnup fraction is used, and then correct analysis can be carried out on the nuclear device.The neutron field distribution is affected by the surrounding medium in the underground nuclear explosion. It will influence the radiation chemical diagnosis. By Monte Carlo simulation, the fuel burnup induced by device and neutron albedo was calculated. The analysis method of albedo effect on radiation chemical diagnosis result under special environment was proposed. Neutron albedo should be considered when capture reaction burnup fraction is used, and then correct analysis can be carried out on the nuclear device. (authors)

  14. The Influence of Supervisor's Transformational Leadership on Learning Culture and Learning Transfer of Nuclear R and D Personnel

    International Nuclear Information System (INIS)

    Min, Sang-Ki; Hwang, Hye-Seon; Jin, You-Rim; Lee, Eui-Jin; Lee, Soo-Jin

    2017-01-01

    Transformational leadership means that supervisors try to support the members individually, and encourage them to find new methods and approaches. In this study, it was identified empirically that a supervisor's transformational leadership has a strong influence on the learning culture and learning transfer of nuclear R and D personnel. To develop the competency of R and D personnel, not only formal education programs but also informal learning such as workplace learning have been carried out in the nuclear R and D organization. In this situation, transformational leadership has an effect on willingness and behavior of nuclear R and D personnel on the formal and informal learning. Therefore, transformational leadership is crucial factor in the human resource development system. The leadership required by them is not a one-sided order, but rather individual consideration, charisma, and intellectual stimulation for their nuclear R and D members. As a point of nuclear training and education, it is necessary to consider the operation of leadership programs that strengthen the transformational leadership of the project managers.

  15. RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS

    International Nuclear Information System (INIS)

    Weber, William J.

    2000-01-01

    The objective of this research was to develop fundamental understanding and predictive models of radiation effects in glasses and ceramics at the atomic, microscopic, and macroscopic levels, as well as an understanding of the effects of these radiation-induced solid-state changes on dissolution kinetics (i.e., radionuclide release). The research performed during the duration of this project has addressed many of the scientific issues identified in the reports of two DOE panels [1,2], particularly those related to radiation effects on the structure of glasses and ceramics. The research approach taken by this project integrated experimental studies and computer simulations to develop comprehensive fundamental understanding and capabilities for predictive modeling of radiation effects and dissolution kinetics in both glasses and ceramics designed for the stabilization and immobilization of high-level tank waste (HLW), plutonium residues and scraps, surplus weapons plutonium, other actinides, and other highly radioactive waste streams. Such fundamental understanding is necessary in the development of predictive models because all experimental irradiation studies on nuclear waste materials are ''accelerated tests'' that add a great deal of uncertainty to predicted behavior because the damage rates are orders of magnitude higher than the actual damage rates expected in nuclear waste materials. Degradation and dissolution processes will change with damage rate and temperature. Only a fundamental understanding of the kinetics of all the physical and chemical processes induced or affected by radiation will lead to truly predictive models of long-term behavior and performance for nuclear waste materials. Predictive models of performance of nuclear waste materials must be scientifically based and address both radiation effects on structure (i.e., solid-state effects) and the effects of these solid-state structural changes on dissolution kinetics. The ultimate goal of this

  16. Degradative crystal–chemical transformations of clay minerals under the influence of cyanobacterium-actinomycetal symbiotic associations

    Directory of Open Access Journals (Sweden)

    Ekaterina Ivanova

    2014-04-01

    Full Text Available Cyanobacteria and actinomycetes are essential components of soil microbial community and play an active role in ash elements leaching from minerals of the parent rock. Content and composition of clay minerals in soil determine the sorption properties of the soil horizons, water-holding capacity of the soil, stickiness, plasticity, etc. The transformative effect of cyanobacterial–actinomycetes associations on the structure of clay minerals – kaolinite, vermiculite, montmorillonite, biotite and muscovite – was observed, with the greatest structural lattice transformation revealed under the influence of association in comparison with monocultures of cyanobacterium and actinomycete. The range of the transformative effect depended both on the type of biota (component composition of association and on the crystal–chemical parameters of the mineral itself (trioctahedral mica – biotite, was more prone to microbial degradation than the dioctahedral – muscovite. The formation of the swelling phase – the product of biotite transformation into the mica–vermicullite mixed-layered formation was revealed as a result of association cultivation. Crystal chemical transformation of vermiculite was accompanied by the removal of potassium (К, magnesium (Mg and aluminum (Al from the crystal lattice. The study of such prokaryotic communities existed even in the early stages of the Earth's history helps to understand the causes and nature of the transformations undergone by the atmosphere, hydrosphere and lithosphere of the planet.contribution of treatments on structure induces and model parameters are discussed in the paper.

  17. Mechanisms of chemical modification of neoplastic cell transformation by ionizing radiation

    International Nuclear Information System (INIS)

    Yang, T.C.; Tobias, C.A.

    1985-01-01

    During space travel, astronauts will be continuously exposed to ionizing radiation; therefore, it is necessary to minimize the radiation damage by all possible means. The authors' studies show that DMSO (when present during irradiation) can protect cells from being killed and transformed by X rays and that low concentration of DMSO can reduce the transformation frequency significantly when it is applied to cells, even many days after irradiation. The process of neoplastic cell transformation is a complicated one and includes at least two different stages: induction and expression. DMSO apparently can modify the radiation damage during both stages. There are several possible mechanisms for the DMSO effect: (1) changing the cell membrane structure and properties; (2) inducing cell differentiation by acting on DNA; and (3) scavanging free radicals in the cell. Recent studies with various chemical agents, e.g., 5-azacytidine, dexamethane, rhodamin-123, etc., indicate that the induction of cell differentiation by acting on DNA may be an important mechanism for the suppression of expression of neoplastic cell transformation by DMSO

  18. Effect of Organic Solvents in Preparation of Silica-Based Chemical Gel Decontaminates for Decontamination of Nuclear Facilities

    International Nuclear Information System (INIS)

    Yoon, Suk Bon; Jung, Chong Hun; Kim, Chang Ki; Choi, Byung Seon; Lee, Kune Woo; Moon, Jei Kwon

    2011-01-01

    Decontamination of nuclear facilities is necessary to reduce the radiation field during normal operations and decommissioning of complex equipment such as stainless steel components, other iron-based steel and alloys, metal surfaces, structural materials and so on. Chemical decontamination technology in particular is a highly effective method to remove the radioactive contamination through a chemical dissolution or a redox reaction. However, this method has the serious drawback due to the generation of large amounts of the radioactive liquid wastes. Recently, a few literatures have been reported for the preparation of the chemical gel decontaminants to reduce the amount of the radioactive liquid wastes and to enhance the decontamination efficiency through increasing the contact time between the gels and the radioactive contaminants. In the preparation of the chemical gels, the control of the viscosity highly depends on the amount of a coviscosifier used among the components of the chemical gels consisted of a viscosifier, a coviscosifier, and a chemical decontaminant. In this works, a new effective method for the preparation of the chemical gel was investigated by introducing the organic solvents. The mixture solution of the coviscosifier and organic solvent was more effective in the control of the viscosity compared with that of the coviscosifier only in gels. Furthermore, the decontamination efficiency of the chemical gels measured by using the multi-channel analyzer (MCA) showed the high decontamination factor for Co-60 and Cs-137 contaminated on the surface of the stainless steel 304

  19. Weapons of mass destruction: Overview of the CBRNEs (Chemical, Biological, Radiological, Nuclear, and Explosives).

    Science.gov (United States)

    Prockop, Leon D

    2006-11-01

    The events of September 11, 2001, made citizens of the world acutely aware of disasters consequent to present-day terrorism. This is a war being waged for reasons obscure to many of its potential victims. The term "NBCs" was coined in reference to terrorist weapons of mass destruction, i.e., nuclear, biological and chemical. The currently accepted acronym is "CBRNE" which includes Chemical, Biological, Radiological, Nuclear, and Explosive weapons. Non-nuclear explosives are the most common terrorist weapon now in use. Nuclear and radiological weapons are beyond the scope of this publication, which focuses on the "CBEs", i.e. chemical, biological and explosive weapons. Although neurologists will not be the first responders to CBEs, they must know about the neurological effects in order to provide diagnosis and treatment to survivors. Neurological complications of chemical, biological and explosive weapons which have or may be used by terrorists are reviewed by international experts in this publication. Management and treatment profiles are outlined.

  20. Impact of TiO2 on the chemical and biological transformation of formulated chiral-metalaxyl in agricultural soils.

    Science.gov (United States)

    Huang, Junxing; Zhang, Xu; Liang, Chuanzhou; Hu, Jun

    2018-04-15

    The impacts of TiO 2 on the chemical and biological transformation of racemic metalaxyl wettable powder (rac-metalaxyl WP) in agricultural soils, and soil microorganisms were investigated. Under simulated solar irradiation, TiO 2 highly promoted the transformation of rac-metalaxyl WP without changing the enantiomer fraction, with the promotion amplitude (60-1280%) being dependent on TiO 2 characteristics. TiO 2 characteristics showed different influence on the transformation of rac-metalaxyl WP in soils and aqueous solutions because their characteristics changed differently in soils. The impact of the mancozeb and other co-constituents on the transformation of rac-metalaxyl WP was smaller in soil media than in aqueous solution. Autoclave sterilization changed soil properties and subsequently weakened the promotion effects of TiO 2 on the chemical transformations of rac-metalaxyl WP to 0-233%. Microorganism biomass and bacterial community were not statistically significant changed by TiO 2 exposure regardless of rac-metalaxyl WP, suggesting that the promotional effects occurred mainly through chemical processes. The results also showed TiO 2 -soil interactions may be strengthened with TiO 2 (Degussa P25) aging time in soils, which decreased its promotion amplitude from 1060% (without aging) to 880% (aging for 20 days). Intermediate formed in soil biological transformation process was different from that in TiO 2 photocatalysis process. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Chemical characterization of nuclear materials: recent trends

    International Nuclear Information System (INIS)

    Prakash, Amrit; Nandi, C.; Patil, A.B.; Khan, K.B.

    2013-01-01

    Analytical chemistry plays a very important role for nuclear fuel activities be it fuel fabrication, waste management or reprocessing. Nuclear fuels are selected based on the type of reactor. The nuclear fuel has to conform to stringent chemical specifications like boron, cadmium, rare earths, hydrogen, oxygen to metal ratio, total gas, heavy metal content, chlorine and fluorine etc. Selection of technique is very important to evaluate the true specification. This is important particularly when the analyses have to perform inside leak tight enclosure. The present paper describes the details of advanced analytical techniques being developed and used in chemical characterization of nuclear materials specially fuels during their fabrication. Nuclear fuels comprise of fuels based on UO 2 , PUO 2 , ThO 2 and combination of (U+Pu)O 2 , (Th+U)O 2 , (Th+Pu)O 2 , (U+Pu)C, (U+Pu)N etc depending on the type of reactors chosen Viz. Pressurized Heavy water Reactor (PHWR), Boiling Water Reactor (BWR), Fast Breeder Test Reactor and Prototype Fast Breeder Reactor (PFBR). Chemical characterization of these fuels is very important for performance of fuel in the reactor. It provides means to ascertain that the quality of the fabricated fuel conforms to the chemical specifications for the fuel laid down by the designer. The batches of sintered/degassed pellets are subjected to comprehensive chemical quality control for trace constituents, stoichiometry and isotopic composition. Chemical Quality Control of fuel is carried out at different stages of manufacture namely feed materials, sintering, vacuum degassing and fuel element welding. Advanced analytical technique based on titrimetry, spectroscopy, thermogravimetry, XRF and XRD have largely been used for this purpose. Since they have to be handled inside special enclosures, extreme care are being taken during handling. Instruments are being developed/modified for ease of handling and maintenance. The method should be fast to reduce

  2. Effects of Irradiation on Albite's Chemical Durability.

    Science.gov (United States)

    Hsiao, Yi-Hsuan; La Plante, Erika Callagon; Krishnan, N M Anoop; Le Pape, Yann; Neithalath, Narayanan; Bauchy, Mathieu; Sant, Gaurav

    2017-10-19

    Albite (NaAlSi 3 O 8 ), a framework silicate of the plagioclase feldspar family and a common constituent of felsic rocks, is often present in the siliceous mineral aggregates that compose concrete. When exposed to radiation (e.g., in the form of neutrons) in nuclear power plants, the crystal structure of albite can undergo significant alterations. These alterations may degrade its chemical durability. Indeed, careful examinations of Ar + -implanted albite carried out using Fourier transform infrared spectroscopy (FTIR) and molecular dynamics simulations show that albite's crystal structure, upon irradiation, undergoes progressive disordering, resulting in an expansion in its molar volume (i.e., a reduction of density) and a reduction in the connectivity of its atomic network. This loss of network connectivity (i.e., rigidity) results in an enhancement of the aqueous dissolution rate of albite-measured using vertical scanning interferometry (VSI) in alkaline environments-by a factor of 20. This enhancement in the dissolution rate (i.e., reduction in chemical durability) of albite following irradiation has significant impacts on the durability of felsic rocks and of concrete containing them upon their exposure to radiation in nuclear power plant (NPP) environments.

  3. Chemical history with a nuclear microprobe

    International Nuclear Information System (INIS)

    Maggiore, C.J.; Benjamin, T.M.; Burnett, D.S.; Hyde, P.J.; Rogers, P.S.Z.; Srinivasan, S.; Tesmer, T.; Woolum, D.S.

    1983-01-01

    A nuclear microprobe cannot give direct information on the chemical state of an element, but the spatial distribution of elements in a specimen is often determined by the chemical history of the sample. Fuel cells and minerals are examples of complex systems whose elemental distributions are determined by past chemical history. The distribution of catalyst in used fuel cell electrodes provides direct information on the chemical stability of dispersed catalysts under operating conditions. The authors have used spatially resolved Rutherford backscattering to measure the migration of platinum and vanadium from intermetallic catalysts and to determine their suitability for use under the extreme operating conditions found in phosphoric acid fuel cells. Geologic materials are complex, heterogeneous samples with small mineral grains. The trace element distribution within the individual mineral grains and between different mineral phases is sensitive to the details of the mineral formation and history. The spatial resolution and sub-100-ppm sensitivity available with a nuclear microprobe open up several new classes of experiments to the geochemist. Geochemistry and electrochemistry are two areas proving particularly fruitful for application of the nuclear microprobe

  4. Factors influencing chemical durability of nuclear waste glasses

    International Nuclear Information System (INIS)

    Feng, Xiangdong; Bates, J.K.

    1993-01-01

    A short summary is given of our studies on the major factors that affect the chemical durability of nuclear waste glasses. These factors include glass composition, solution composition, SA/V (ratio of glass surface area to the volume of solution), radiation, and colloidal formation. These investigations have enabled us to gain a better understanding of the chemical durability of nuclear waste glasses and to accumulate.a data base for modeling the long-term durability of waste glass, which will be used in the risk assessment of nuclear waste disposal. This knowledge gained also enhances our ability to formulate optimal waste glass compositions

  5. Uranium for Nuclear Power: Resources, Mining and Transformation to Fuel

    International Nuclear Information System (INIS)

    Hore-Lacy, Ian

    2016-01-01

    Uranium for Nuclear Power: Resources, Mining and Transformation to Fuel discusses the nuclear industry and its dependence on a steady supply of competitively priced uranium as a key factor in its long-term sustainability. A better understanding of uranium ore geology and advances in exploration and mining methods will facilitate the discovery and exploitation of new uranium deposits. The practice of efficient, safe, environmentally-benign exploration, mining and milling technologies, and effective site decommissioning and remediation are also fundamental to the public image of nuclear power. This book provides a comprehensive review of developments in these areas: • Provides researchers in academia and industry with an authoritative overview of the front end of the nuclear fuel cycle • Presents a comprehensive and systematic coverage of geology, mining, and conversion to fuel, alternative fuel sources, and the environmental and social aspects • Written by leading experts in the field of nuclear power, uranium mining, milling, and geological exploration who highlight the best practices needed to ensure environmental safety

  6. Chemically Induced Phase Transformation in Austenite by Focused Ion Beam

    Science.gov (United States)

    Basa, Adina; Thaulow, Christian; Barnoush, Afrooz

    2014-03-01

    A highly stable austenite phase in a super duplex stainless steel was subjected to a combination of different gallium ion doses at different acceleration voltages. It was shown that contrary to what is expected, an austenite to ferrite phase transformation occurred within the focused ion beam (FIB) milled regions. Chemical analysis of the FIB milled region proved that the gallium implantation preceded the FIB milling. High resolution electron backscatter diffraction analysis also showed that the phase transformation was not followed by the typical shear and plastic deformation expected from the martensitic transformation. On the basis of these observations, it was concluded that the change in the chemical composition of the austenite and the local increase in gallium, which is a ferrite stabilizer, results in the local selective transformation of austenite to ferrite.

  7. UK Chemical Nuclear Data Committee: progress report

    International Nuclear Information System (INIS)

    Nichols, A.L.

    1992-02-01

    Studies of the basic nuclear data for commercial and industrial application are monitored by the UK Chemical Nuclear Data Committee (UKCNDC). Such data are defined on the basis of chemical methods of analysis, and include half-lives, decay parameters and fission yields. Work undertaken within this area is described in this document for information. (author)

  8. Inherently safe technologies-chemical and nuclear

    International Nuclear Information System (INIS)

    Weinberg, A.M.

    1984-01-01

    Probabilistic risk assessments show an inverse relationship between the likelihood and the consequences of nuclear and chemical plant accidents, but the Bhopal accident has change public complacency about the safety of chemical plants to such an extent that public confidence is now at the same low level as with nuclear plants. The nuclear industry's response was to strengthen its institutions and improve its technologies, but the public may not be convinced. One solution is to develop reactors which do not depend upon the active intervention of humans of electromechanical devices to deal with emergencies, but which have physical properties that limit the possible temperature and power of a reactor. The Process Inherent Ultimately Safe and the modular High-Temperature Gas-Cooled reactors are two possibilities. the chemical industry needs to develop its own inherently safe design precepts that incorporate smallness, safe processes, and hardening against sabotage. 5 references

  9. Dismantlement and destruction of chemical, nuclear and conventional weapons

    International Nuclear Information System (INIS)

    Schulte, N.T.

    1997-01-01

    The safe destruction and dismantling of chemical, nuclear and conventional weapons is of fundamental importance to the security of all countries represented in this volume. Expertise in the field is not confined to one country or organisation: all can benefit from each other. There is an ever present danger of proliferation of weapons of mass destruction: approximately two dozen countries have ongoing programmes to develop or acquire such weapons, and many are also gaining the capability to build air-surface delivery systems. But much can be done to prevent proliferation by reducing leakage of materials and know-how and by solving the problems of the destruction of surplus weapons systems, which has now come to be a key issue. In 13 sessions of the workshop attention was paid to (1) Dismantlement and Destruction of Chemical, Nuclear and Conventional Weapons; (2) Status of Implementation of Arms Control Treaties and Voluntary Commitments; (3) National Perspectives on Cooperation in Disarmament; (4) Stocktaking of National and Bilateral Disposal/Destruction Programmes: Chemical Weapons; (5) Stocktaking of National and Bilateral Disposal/Destruction Programmes: Nuclear Weapons; (6) Stocktaking of National and Bilateral Disposal/Destruction Programmes: Conventional Weapons. Session; (7) Experience with Currently Employed Chemical Destruction Technologies; (8) Alternative Chemical Destruction Technologies; (9) Deactivation, Dismantlement and Destruction of Delivery Systems and Infrastructure for Nuclear Weapons; (10) Storage, Safeguarding and Disposition of Fissile Materials; (11) Technologies for Conversion and Civil Use of Demilitarized Materials; (12) International Organizations; and (13) Environmental Challenges Posed by Chemical and Nuclear Disarmament

  10. Nuclear industry - challenges in chemical engineering

    International Nuclear Information System (INIS)

    Sen, S.; Sunder Rajan, N.S.; Balu, K.; Garg, R.K.; Murthy, L.G.K.; Ramani, M.P.S.; Rao, M.K.; Sadhukhan, H.K.; Venkat Raj, V.

    1978-01-01

    Chemical engineering processes and operations are closely involved in every step of the nuclear fuel cycle. Starting from mining and milling of the ore through the production of fuel and other materials and their use in nuclear reactors, fuel reprocessing, fissile material recycle and treatment and disposal of fission product wastes, each step presents a challenge to the chemical engineer to evolve and innovate processes and techniques for more efficient utilization of the energy in the atom. The requirement of high recovery of the desired components at high purity levels is in itself a challenge. ''Nuclear Grade'' specifications for materials put a requirement which very few industries can satisfy. Recovery of uranium and thorium from low grade ores, of heavy water from raw water, etc. are examples. Economical and large scale separation of isotopes particularly those of heavy elements is a task for which processess are under various stages of development. Further design of chemical plants such as fuel reprocessing plants and high level waste treatment plants, which are to be operated and maintained remotely due to the high levels of radio-activity call for engineering skills which are being continually evolved. In the reactor, analysis of the fluid mechanics and optimum design of heat removal system are other examples where a chemical engineer can play a useful role. In addition to the above, the activities in the nuclear industry cover a very wide range of chemical engineering applications, such as desalination and other energy intensive processes, radioisotope and radiation applications in industry, medicine and agriculture. (auth.)

  11. Stable nuclear transformation of Eudorina elegans

    Directory of Open Access Journals (Sweden)

    Lerche Kai

    2013-02-01

    Full Text Available Abstract Background A fundamental step in evolution was the transition from unicellular to differentiated, multicellular organisms. Volvocine algae have been used for several decades as a model lineage to investigate the evolutionary aspects of multicellularity and cellular differentiation. There are two well-studied volvocine species, a unicellular alga (Chlamydomonas reinhardtii and a multicellular alga with differentiated cell types (Volvox carteri. Species with intermediate characteristics also exist, which blur the boundaries between unicellularity and differentiated multicellularity. These species include the globular alga Eudorina elegans, which is composed of 16–32 cells. However, detailed molecular analyses of E. elegans require genetic manipulation. Unfortunately, genetic engineering has not yet been established for Eudorina, and only limited DNA and/or protein sequence information is available. Results Here, we describe the stable nuclear transformation of E. elegans by particle bombardment using both a chimeric selectable marker and reporter genes from different heterologous sources. Transgenic algae resistant to paromomycin were achieved using the aminoglycoside 3′-phosphotransferase VIII (aphVIII gene of Streptomyces rimosus, an actinobacterium, under the control of an artificial promoter consisting of two V. carteri promoters in tandem. Transformants exhibited an increase in resistance to paromomycin by up to 333-fold. Co-transformation with non-selectable plasmids was achieved with a rate of 50 - 100%. The luciferase (gluc gene from the marine copepod Gaussia princeps, which previously was engineered to match the codon usage of C. reinhardtii, was used as a reporter gene. The expression of gluc was mediated by promoters from C. reinhardtii and V. carteri. Heterologous heat shock promoters induced an increase in luciferase activity (up to 600-fold at elevated temperatures. Long-term stability and both constitutive and

  12. Chemical process measurements in PWR-type nuclear power plants

    International Nuclear Information System (INIS)

    Glaeser, E.

    1978-01-01

    In order to achieve high levels of availability of nuclear power plants equipped with pressurized water reactors, strict standards have to be applied to the purity of coolant and of other media. Chemical process measurements can meet these requirements only if programmes are established giving maximum information with minimum expenditure and if these programmes are realized with effective analytical methods. Analysis programmes known from literature are proved for their usefulness, and hints are given for establishing rational programmes. Analytical techniques are compared with each other taking into consideration both methods which have already been introduced into nuclear power plant practice and methods not yet generally used in practice, such as atomic absorption spectrophotometry, gas chromatography, etc. Finally, based on the state of the art of chemical process measurements in nuclear power plants, the trends of future development are pointed out. (author)

  13. Nuclear chemical method for preparation of free carbenium ions and radiochemical investigation of reactions of these particles

    International Nuclear Information System (INIS)

    Nefedov, V.D.; Sinotova, E.N.; Toropova, M.A.

    1980-01-01

    Tritium nuclear transformation (β-decay) in the composition of the molecules of hydrocarbons, appearance of primary molecular ions and formation of free carbenium ion are the main items of nuclear-chemical method of preparation of free carbenium ions. The method permits to prepare carbenium ions present in free state, i.e. without counterion and without solvate sheath of variou nitial localization of the charge. The rate of carbenium ion generation is strictly definite and does not depend upon outer conditions. The method suggested permits to prepare carbenium ions in all phases, study their reactions with individual substances in gaseous, liquid and solid states. The study of ion-molecular reactions is carried out using radiochemical method. The analysis of the products is made using the method of gaseous radiochromatography. Development of preparation techniques of carbenium ions and their analogues, study of the reactions of these particles with different classes of compounds, investigation of the effect of different factors upon procedure of ion-molecular reactions are the main directions of the investigations

  14. Management of risks in the chemical and nuclear areas

    International Nuclear Information System (INIS)

    Venuti, G.C.; Frullani, S.; Pocchiari, F.; Rogani, A.; Silano, V.; Tabet, E.; Zapponi, G.

    1984-01-01

    A comparative overview is provided of some major aspects concerning assessment and management of chemical and nuclear risks arising as a consequence of accidents. Statutory procedures for constructing and running nuclear and chemical plants in Italy are discussed in detail. Special attention is given to the major changes that are likely to occur after the adoption of the EEC Council Directive 82/501, designed to prevent major accidents which might result from certain industrial activities and to limit their consequences for humans and their environment. Present status and future trends of accident analysis and risk assessment are also dealt with, and special emphasis is placed on aspects common to both nuclear and chemical plants. Lastly, managerial aspects of contingency planning for, and response to, emergencies and accidents involving toxic chemical and/or ionizing radiations are examined with the aim of identifying more critical steps. (author)

  15. Cutaneous reactions in nuclear, biological and chemical warfare

    Directory of Open Access Journals (Sweden)

    Arora Sandeep

    2005-03-01

    Full Text Available Nuclear, biological and chemical warfare have in recent times been responsible for an increasing number of otherwise rare dermatoses. Many nations are now maintaining overt and clandestine stockpiles of such arsenal. With increasing terrorist threats, these agents of mass destruction pose a risk to the civilian population. Nuclear and chemical attacks manifest immediately while biological attacks manifest later. Chemical and biological attacks pose a significant risk to the attending medical personnel. The large scale of anticipated casualties in the event of such an occurrence would need the expertise of all physicians, including dermatologists, both military and civilian. Dermatologists are uniquely qualified in this respect. This article aims at presenting a review of the cutaneous manifestations in nuclear, chemical and biological warfare and their management.

  16. Study of the mechanism of radiation-chemical transformations in rubber-resinous materials

    International Nuclear Information System (INIS)

    Sharova, L.B.; Astakhova, L.G. Trufanova, N.D.; Persinen, A.A.; Vasil'ev, I.A.

    1993-01-01

    Materials based on butadiene-nitrile rubbers reinforced by phenol-formaldehyde resins presently find wide application as reliable heat-insulating coatings for various metallic constructions and are utilized under exposure to ionizing radiation. In this connection, when estimating the assured lifetime of heat-insulating coatings, it is necessary to take into account the character and degree of their radiation-chemical transformations. The aim of the present work was to study the radiation-chemical transformations of materials based on a composite of butadiene-nitrile rubber and phenol-formaldehyde resin. The investigations were carried out on model materials S-O, S-25, S-100, S-130, and S-150 based on the SKN-40M rubber with a varied content of SF-010A brand phenol-formaldehyde resin, the content of which in parts by weight per 100 parts by weight of rubber is indicated in the specifications of the materials. The possible directions of the radiation-chemical transformations in the rubber-resinous vulcanizates were studied by the method of disrupted total internal reflection (MDTIR) IR spectroscopy

  17. Speeding through cell cycle roadblocks: Nuclear cyclin D1-dependent kinase and neoplastic transformation

    Directory of Open Access Journals (Sweden)

    Diehl J Alan

    2008-09-01

    Full Text Available Abstract Mitogenic induction of cyclin D1, the allosteric regulator of CDK4/6, is a key regulatory event contributing to G1 phase progression. Following the G1/S transition, cyclin D1 activation is antagonized by GSK3β-dependent threonine-286 (Thr-286 phosphorylation, triggering nuclear export and subsequent cytoplasmic degradation mediated by the SCFFbx4-αBcrystallin E3 ubiquitin ligase. Although cyclin D1 overexpression occurs in numerous malignancies, overexpression of cyclin D1 alone is insufficient to drive transformation. In contrast, cyclin D1 mutants refractory to phosphorylation-dependent nuclear export and degradation are acutely transforming. This raises the question of whether overexpression of cyclin D1 is a significant contributor to tumorigenesis or an effect of neoplastic transformation. Significantly, recent work strongly supports a model wherein nuclear accumulation of cyclin D1-dependent kinase during S-phase is a critical event with regard to transformation. The identification of mutations within SCFFbx4-αBcrystallin ligase in primary tumors provides mechanistic insight into cyclin D1 accumulation in human cancer. Furthermore, analysis of mouse models expressing cyclin D1 mutants refractory to degradation indicate that nuclear cyclin D1/CDK4 kinase triggers DNA re-replication and genomic instability. Collectively, these new findings provide a mechanism whereby aberrations in post-translational regulation of cyclin D1 establish a cellular environment conducive to mutations that favor neoplastic growth.

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

    International Nuclear Information System (INIS)

    Hoffman, D.C.

    1990-08-01

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

  19. Advances in chemical engineering in nuclear and process industries

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-06-01

    Symposium on Advances in Chemical Engineering in Nuclear and Process Industries dealt with a wide spectrum of areas encompassing various industries such as nuclear, fertilizer, petrochemical, refinery and cement. The topics covered in the symposium dealt with the advancements in the existing fields of science and technologies as well as in some of the emerging technologies such as membrane technology, bio-chemical and photo-chemical engineering etc. with a special emphasis on nuclear related aspects. Papers relevant to INIS are indexed separately.

  20. Advances in chemical engineering in nuclear and process industries

    International Nuclear Information System (INIS)

    1994-06-01

    Symposium on Advances in Chemical Engineering in Nuclear and Process Industries dealt with a wide spectrum of areas encompassing various industries such as nuclear, fertilizer, petrochemical, refinery and cement. The topics covered in the symposium dealt with the advancements in the existing fields of science and technologies as well as in some of the emerging technologies such as membrane technology, bio-chemical and photo-chemical engineering etc. with a special emphasis on nuclear related aspects. Papers relevant to INIS are indexed separately

  1. Safety criteria for nuclear chemical plants

    International Nuclear Information System (INIS)

    Ball, P.W.; Curtis, L.M.

    1983-01-01

    Safety measures have always been required to limit the hazards due to accidental release of radioactive substances from nuclear power plants and chemical plants. The risk associated with the discharge of radioactive substances during normal operation has also to be kept acceptably low. BNFL (British Nuclear Fuels Ltd.) are developing risk criteria as targets for safe plant design and operation. The numerical values derived are compared with these criteria to see if plants are 'acceptably safe'. However, the criteria are not mandatory and may be exceeded if this can be justified. The risk assessments are subject to independent review and audit. The Nuclear Installations Inspectorate also has to pass the plants as safe. The assessment principles it uses are stated. The development of risk criteria for a multiplant site (nuclear chemical plants tend to be sited with many others which are related functionally) is discussed. This covers individual members of the general public, societal risks, risks to the workforce and external hazards. (U.K.)

  2. Monitoring systems online of oil for transformers of nuclear power plants

    International Nuclear Information System (INIS)

    Sarandeses, S.

    2014-01-01

    The nuclear power plants are showing their concern due to the existence of recent failures related to the bulky transformers of power. These transformers are not security, but are important for the production of power as its failure can cause transient on the floor, reactor scram or shooting, that can cause interruptions in the production of energy or might force us to reduce the power of production The analysis of gases dissolved in transformer oil is recognized as a trial key to identify a submerged transformer failure in oil. With this analysis it is not possible to ensure that there is no damage in the transformer, but the probability of risk of this type of failure can be reduced. The industry recommended to equip the new large power transformers with oil online monitoring systems and in some cases also be It recommended its use in existing transformers. (Author)

  3. American Chemical Society. Division of Nuclear Chemistry and Technology

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The meeting of the 201st American Chemical Society Division of Nuclear Chemistry and Technology was comprised from a variety of topics in this field including: nuclear chemistry, nuclear physics, and nuclear techniques for environmental studies. Particular emphasis was given to fundamental research concerning nuclear structure (seven of the nineteen symposia) and studies of airborne particle monitoring and transport (five symposia). 105 papers were presented

  4. Temperature effects on chemical structure and motion in coal. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Maciel, G.E.

    1996-09-30

    The objective of this project was to apply recently developed, state-of-the-art nuclear magnetic resonance (NMR) techniques to examine in situ changes in the chemical structure and molecular/macromolecular motion in coal as the temperature is increased above room temperature. Although alterations in the chemical structure of coal have been studied previously by {sup 13}C NMR, using quenched samples, the goal of this project was to examine these chemical structural changes, and changes in molecular/macromolecular mobility that may precede or accompany the chemical changes, at elevated temperatures, using modern {sup 13}C and {sup 1}H NMR techniques, especially {sup 1}H dipolar-dephasing techniques and related experiments pioneered in the laboratory for examining pyridine-saturated coals. This project consisted of the following four primary segments and related efforts on matters relevant to the first four tasks. (1) {sup 1}H NMR characterization of coal structure and mobility as a function of temperature variation over a temperature range (30--240 C) for which substantial chemical transformations were not anticipated. (2) {sup 1}H NMR characterization of coal structure, mobility and conversion as a function of temperature variation over a temperature range (240--500 C) for which chemical transformations of coal are known to occur. (3) {sup 13}C NMR investigation of coal structure/mobility as a function of temperature over a temperature range (30--240 C) for which substantial chemical transformations were not anticipated. (4) {sup 13}C NMR investigation of coal structure, dynamics and conversion as a function of temperature variation over a range (240--500 C) for which chemical transformations of coal are known to occur. (5) Related matters relevant to the first four tasks: (a) {sup 1}H CRAMPS NMR characterization of oil shales and their kerogen concentrates; and (b) improved quantitation in {sup 13}C MAS characterization of coals.

  5. Survey of Nuclear Methods in Chemical Technology

    International Nuclear Information System (INIS)

    Broda, E.

    1966-01-01

    An attempt is made to classify nuclear methods on a logical basis to facilitate assimilation by the technologist. The three main groups are: (I) Tracer methods, (II) Methods based on the influence of absorbers on radiations to be measured, and (III) Radiation chemical methods. The variants of the first two groups are discussed in some detail, and typical examples are given. Group I can be subdivided into (1) Indicator methods, (2) Emanation methods, (3) Radioreagent methods, and (4) Isotope dilution methods, Group II into (5) Activation methods, (6) Absorption methods, (7) Induced Nuclear Reaction methods, (8) Scattering methods, and (9) Fluorescence methods. While the economic benefits due to nuclear methods already run into hundreds of millions of dollars annually, owing to radiation protection problems radiochemical methods in the strict sense are not widely used in actual production. It is suggested that more use should be made of pilot plant tracer studies of chemical processes as used in industry. (author)

  6. Chemical aspects of nuclear waste treatment

    International Nuclear Information System (INIS)

    Bond, W.D.

    1980-01-01

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

  7. Structural changes in amorphous organic compounds and their role during chemical transformations

    International Nuclear Information System (INIS)

    Gusakovskaya, I.G.

    1994-01-01

    Using butanediol vinylacetate and dimetacrylate as an example, it can be shown that structural changes of amorphous-liquid substance play an important part at chemical transformations of amorphous compounds and chemical reaction rate provides an function of local order. When the amorphous polymer is viewed as an system of multiple transformations, each gives birth to the definite local order, the calculation of recombination reaction of active centers accumulated during irradiation of polymer at 77 K is carried out. Concentration of recombinated centers rises steeply near each transformation T k

  8. Final report on 'biological effects of tritium as a basis of research and development in nuclear fusion'

    International Nuclear Information System (INIS)

    1987-12-01

    The National Institute of Radiological Sciences, Japan, has undertaken a special study of ''biological effects of tritium as a basis of research and development in nuclear fusion'' over a 5-year period from April 1981 through March 1986. This is a final report, covering incorporation and metabolism of tritium, physical, chemical, and cellular effects of tritium, tritium damage to the mammalian tissue, and human exposure to tritium. The report is organized into five chapters, including ''Study of incorporation of tritium into the living body and its in vivo behavior''; ''Physical and chemical studies for the determination of relative biological effectiveness''; ''Analytical study on biological effects of tritium in cultured mammalian cells''; ''Study of tritium effects on the mammalian tissue, germ cells, and cell transformation''; and ''Changes in the hemopoietic stem cells and lymphocyte subsets in humans after exposure to some internal emitters''. (Namekawa, K.)

  9. Study of the mineralogical transformations of granite by underground nuclear explosions

    International Nuclear Information System (INIS)

    Faure, Jean

    1970-01-01

    The object of the following communication is to prove new data about the petrographic effects of the underground nuclear explosions. It is founded on the results of trench tests in granite rock. The samples are collected by drilling and the temperature of the rock was measured in the hole. Four types of melted rocks can be sorted, grey-green glass and pumices, beige to red-brown pumices, dark lavas, dark veinlets and crushed granite. The distribution of these rocks is studied. Optical microscopy, X-rays and chemical analysis, study by electron probe, are made. The results complete previously published data. They are interesting as far as the use of nuclear explosions for industrial applications is concerned. (author)

  10. Study of the mineralogical transformations of granite by underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Faure, Jean [Commissariat a I' Energie Atomique, Centre d' Etudes de Bruyeres-le-Chatel (France)

    1970-05-15

    The object of the following communication is to prove new data about the petrographic effects of the underground nuclear explosions. It is founded on the results of trench tests in granite rock. The samples are collected by drilling and the temperature of the rock was measured in the hole. Four types of melted rocks can be sorted, grey-green glass and pumices, beige to red-brown pumices, dark lavas, dark veinlets and crushed granite. The distribution of these rocks is studied. Optical microscopy, X-rays and chemical analysis, study by electron probe, are made. The results complete previously published data. They are interesting as far as the use of nuclear explosions for industrial applications is concerned. (author)

  11. Escalation of terrorism? On the risk of attacks with chemical, biological, radiological and nuclear weapons or materials

    International Nuclear Information System (INIS)

    Nass, Jens

    2010-01-01

    The report on the risk of attacks with chemical, biological, radiological and nuclear weapons or materials covers the following topics: the variety of terrorism: ethnic-nationalistic, politically motivated, social revolutionary, political extremism, religious fanaticism, governmental terrorism; CBRN (chemical, biological, radiological, nuclear) weapons and materials: their availability and effectiveness in case of use; potential actor groups; prevention and counter measures, emergency and mitigating measures.

  12. Continuous-Flow Processes in Heterogeneously Catalyzed Transformations of Biomass Derivatives into Fuels and Chemicals

    Directory of Open Access Journals (Sweden)

    Antonio A. Romero

    2012-07-01

    Full Text Available Continuous flow chemical processes offer several advantages as compared to batch chemistries. These are particularly relevant in the case of heterogeneously catalyzed transformations of biomass-derived platform molecules into valuable chemicals and fuels. This work is aimed to provide an overview of key continuous flow processes developed to date dealing with a series of transformations of platform chemicals including alcohols, furanics, organic acids and polyols using a wide range of heterogeneous catalysts based on supported metals, solid acids and bifunctional (metal + acidic materials.

  13. UK Chemical Nuclear Data Committee request list - 1990

    International Nuclear Information System (INIS)

    Nichols, A.L.

    1990-03-01

    The 1986 UK request list for chemical nuclear data has been reviewed in detail by members of the UK Chemical Nuclear Data Committee. New requirements for data measurements and evaluations have been identified, and specific requests have been withdrawn. A new UK request list has evolved, and is given in the form of tabulations covering measurements and evaluations. (author)

  14. Radiation-chemical transformations of antioxidants of alkylated phenols class. 3. 2.2'-methylene-bis-4-methyl-6-tret-butylphenol bis-phenol transformations in the absence of oxygen

    International Nuclear Information System (INIS)

    Antonova, E.A.; Zhirkova, O.A.

    1993-01-01

    Experimental results on radiation-chemical yields of products in the course of bisphenol-agidol transformations in n-decane in the absence of oxygen are presented. It is ascertained that monophenols of different structure are the main stable products of radiation-chemical transformations of agidol. Radiation-chemical mechanism of required product formation is discussed

  15. Imaging properties of the mesooptical Fourier transform microscope for nuclear research emulsion

    International Nuclear Information System (INIS)

    Bencze, Gy.L.; Soroko, L.M.

    1987-01-01

    The optical signal transformation in the Mesooptical Fourier Transform Microscope (MFTM) for nuclear emulsion is treated in terms of Fourier Optics. A continuous conversion of the traditional optical microscope into the MFTM is followed. The images of dot-like and straight line objects given by the MFTM are discussed

  16. A systematic model identification method for chemical transformation pathways – the case of heroin biomarkers in wastewater

    DEFF Research Database (Denmark)

    Ramin, Pedram; Valverde Pérez, Borja; Polesel, Fabio

    2017-01-01

    This study presents a novel statistical approach for identifying sequenced chemical transformation pathways in combination with reaction kinetics models. The proposed method relies on sound uncertainty propagation by considering parameter ranges and associated probability distribution obtained...... at any given transformation pathway levels as priors for parameter estimation at any subsequent transformation levels. The method was applied to calibrate a model predicting the transformation in untreated wastewater of six biomarkers, excreted following human metabolism of heroin and codeine. The method....... Results obtained suggest that the method developed has the potential to outperform conventional approaches in terms of prediction accuracy, transformation pathway identification and parameter identifiability. This method can be used in conjunction with optimal experimental designs to effectively identify...

  17. Transformation strain by chemical disordering in silicon carbide

    International Nuclear Information System (INIS)

    Li Ju

    2004-01-01

    Swelling is observed in radiation-induced amorphization of SiC, which can be attributed to both structural and chemical disordering. By first-principles calculations, an attempt is made to separate the two factors by creating complete chemical disorder with no initial structural disorder in a 64-atom supercell. By relaxing all stresses and internal forces, significant transformation strains, both hydrostatic and shear, are observed. The relaxed configurations are found to be metallic. Softening of the bulk modulus is found to correlate closely with volume expansion, regardless of whether the expansion is caused by structural or chemical disordering, or with no disorder at all. It is postulated that partial chemical disordering contributes significantly to the internal residual stresses and macroscopic swelling of amorphous SiC

  18. Nuclear DNA synthesis rate and labelling index: effects of carcinogenic and non-carcinogenic chemicals on its behaviour in the organism of growing CBA mice

    International Nuclear Information System (INIS)

    Amlacher, E.; Rudolph, C.

    1978-01-01

    Well known bioassays have been compared with the author's thymidine incorporation-screening system and other assays based on biochemical quantification of DNA synthesis as a possibility of identification of carcinogens. The partial inhibition of the whole DNA synthesis in a proliferating cell population after treatment with toxic and carcinogenic chemicals is an early common response especially in hepatectomized animal, livers caused by the effects of those substances. However, by quantitative evaluation of the nuclear DNA synthesis rate as a basic parameter, using autoradiographs of kidney and liver of juvenile growing CBA mice, it is possible to differentiate carcinogenic from non-carcinogenic chemicals by means of silver grain counting after 3 H-TdR incorporation. On the contrary, the whole DNA synthesis, expressed by the 3 H-labelling index (in per cent) of kidney and liver, did not permit such a differentiation in the experimental arrangement used. It could be demonstrated that carcinogenic compounds of different chemical classes partially inhibit the nuclear DNA synthesis rate significantly over a period of more than 24 hours. The tested non-carcinogenic compounds did not show this suppressive effect on the nuclear DNA synthesis rate. (author)

  19. The main chemical safety problems in main process of nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

    Song Fengli; Zhao Shangui; Liu Xinhua; Zhang Chunlong; Lu Dan; Liu Yuntao; Yang Xiaowei; Wang Shijun

    2014-01-01

    There are many chemical reactions in the aqueous process of nuclear fuel reprocessing. The reaction conditions and the products are different so that the chemical safety problems are different. In the paper the chemical reactions in the aqueous process of nuclear fuel reprocessing are described and the main chemical safety problems are analyzed. The reference is offered to the design and accident analysis of the nuclear fuel reprocessing plant. (authors)

  20. The Characteristics of an Effective Nuclear Regulator

    International Nuclear Information System (INIS)

    Cheok, Michael; Wertelaers, An; Lojk, Robert; Santini, Miguel; Alm-Lytz, Kirsi; Rigail, Anne-Cecile; Weidenbruck, Kai-Jochen; Stoppa, Gisela; Rainieri, Roberto; Aoki, Masahiro; Gonzalez-Mercado; Miroshnichenko, Mikhail; Kuznetsov, Nikolay; Kudryavtsev, Evgeny; Cid, Rafael; Franzen, Anna; Skanberg, Lars; Gibson, Steve; Golshan, Mina; Cheok, Michael; Nicic, Adriana; Salgado, Nancy; Creswell, Len

    2014-01-01

    Both national and international organisations agree that the fundamental objective of all nuclear safety regulatory bodies - the regulator's prime purpose - is to ensure that nuclear licensees operate their facilities at all times in a safe manner. Much has been written about ways to improve regulatory processes or to improve the effectiveness of a regulatory body, including in previous OECD/NEA regulatory guidance booklets. But until now, none have focused on the characteristics of an effective nuclear safety regulator. Effective organisations are those that have good leadership and are able to transform strategic direction into operational programmes. Effectiveness is about how well the organisation is achieving its fundamental purpose - in the case of a nuclear safety regulator, ensuring that licensees operate their facilities and discharge their obligations in a safe manner. This regulatory guidance booklet describes the characteristics of an effective nuclear safety regulator in terms of roles and responsibilities, principles and attributes. Each of the characteristics discussed in this report is a necessary feature of an effective nuclear safety regulator but no one characteristic is sufficient on its own. It is the combination of these characteristics that leads to the effectiveness of a nuclear regulatory body. The report provides a unique resource to countries with existing, mature regulators and can be used for benchmarking as well as training and developing staff. It will also be useful for new entrant countries in the process of developing and maintaining an effective nuclear safety regulator. (authors)

  1. System for chemical decontamination of nuclear reactor primary systems

    International Nuclear Information System (INIS)

    Schlonski, J.S.; McGiure, M.F.; Corpora, G.J.

    1992-01-01

    This patent describes a method of chemically decontaminating a nuclear reactor primary system, having a residual heat removal system with one or more residual heat removal heat exchangers, each having an upstream and a downstream side, at or above ambient pressure. It comprises: injecting decontamination chemicals using an injection means; circulating the injected decontamination chemicals throughout the primary system; directing the circulated decontamination chemicals and process fluids to a means for removing suspended solids and dissolved materials after the circulated chemicals and process fluids have passed through the residual heat removal heat exchanger; decontaminating the process fluids; and feeding the decontaminated process fluids to the injection means. This patent also describes a chemical decontamination system for use at, or above, ambient pressure in a nuclear reactor primary system having a residual heat removal system. It comprises: means for injecting decontamination chemicals into the primary system; means for removing dissolved and suspended materials and decontamination chemicals from the primary system; one or more residual heat removal pumps; means located downstream of one of the residual heat removal heat exchangers; and a return line connecting the means

  2. Chemical engineering side of nuclear fusion power

    International Nuclear Information System (INIS)

    Johnson, E.F.

    1976-10-01

    It is widely recognized that chemical engineering has important roles to play in the development of national and world wide energy resources through optimal utilization of fossil fuel reserves. It is much less appreciated that there are crucial chemical engineering problems in the development of energy production from other sources. In particular the successful development of nuclear fusion power generating systems will require the solution of many problems that are uniquely suited to chemical engineers. This article presents a brief overview of the fusion development program and an identification of the major technological problems remaining to be solved

  3. Structure and behavior as determinants: United States nuclear test ban and chemical and biological arms control policy

    International Nuclear Information System (INIS)

    Reich, J.C.

    1991-01-01

    US efforts to control chemical and biological warfare and nuclear testing are examined with the aim of explaining the paucity of US backed agreements in these areas. Two theoretical perspectives, the behavioral and structural approaches, are used to explore US arms control outcomes. In the behavioral approach, the effects of governmental organization and the bargaining dynamics of policy-making elites with different cognitive styles are posited as important influences on US nuclear test ban and chemical and biological arms control policy outcomes. The behavioral perspective accounts for the timing of all US failed and successful entries (with one exception) into nuclear test bans and chemical and biological warfare restraints. A shortcoming of the behavior approach, however, is that it tends to overemphasize the chances for successful US entry into nuclear test and chemical and biological warfare limitations. Analysis of the same events from the structural perspective helps to correct for expectations generated by behavioral variables for a higher success rate than ultimately resulted. In the structural approach, the focus is on the effect of the organization of international politics on US nuclear test ban and chemical and biological arms control policy outcomes

  4. Lectures notes on phase transformations in nuclear matter

    CERN Document Server

    López, Jorge A

    2000-01-01

    The atomic nucleus, despite of being one of the smallest objects found in nature, appears to be large enough to experience phase transitions. The book deals with the liquid and gaseous phases of nuclear matter, as well as with the experimental routes to achieve transformation between them.Theoretical models are introduced from the ground up and with increasing complexity to describe nuclear matter from a statistical and thermodynamical point of view. Modern critical phenomena, heavy ion collisions and computational techniques are presented while establishing a linkage to experimental data.The

  5. Challenge towards plant recombinant protein expression: instability in nuclear and chloroplast transformation

    Energy Technology Data Exchange (ETDEWEB)

    Amiri, M.; Jalali-Javaran, M.; Ehsani, P.; Haddad, R.

    2016-07-01

    It is crucial to maintain the stability of transgene and its expression level. It seems the transformation method and the target organ can influence this instability. To this aim, two transformation systems, Agrobacterium-mediated and particle bombardment systems which have been applied to introduce tissue plasminogen activator (tPA) into nuclear and chloroplast respectively, have been compared to determine transformation efficiency and tPA expression and stability. The presence of tPA gene in transformants has been confirmed by PCR analysis. The gene expression in nuclear transformants and homoplasmy in transplastomic plants have been assayed by ELISA and southern blot, respectively. Some of the Agrobacterium-derived transformants have shown the heritability and stability of the integrated T-DNA harboring the transgene which encodes the tissue plasminogen activator and instability of its expression in T1 generation. Using Southern blot analysis of bombardment-mediated transformants has surprisingly led to detecting the inheritability of tPA. There are several factors lead to silencing of transgene in transgenic plants which should be considered. Possible reasons for these silencing are like vector designing, methylation, copy number, and genome rearrangement.

  6. Challenge towards plant recombinant protein expression: instability in nuclear and chloroplast transformation

    International Nuclear Information System (INIS)

    Amiri, M.; Jalali-Javaran, M.; Ehsani, P.; Haddad, R.

    2016-01-01

    It is crucial to maintain the stability of transgene and its expression level. It seems the transformation method and the target organ can influence this instability. To this aim, two transformation systems, Agrobacterium-mediated and particle bombardment systems which have been applied to introduce tissue plasminogen activator (tPA) into nuclear and chloroplast respectively, have been compared to determine transformation efficiency and tPA expression and stability. The presence of tPA gene in transformants has been confirmed by PCR analysis. The gene expression in nuclear transformants and homoplasmy in transplastomic plants have been assayed by ELISA and southern blot, respectively. Some of the Agrobacterium-derived transformants have shown the heritability and stability of the integrated T-DNA harboring the transgene which encodes the tissue plasminogen activator and instability of its expression in T1 generation. Using Southern blot analysis of bombardment-mediated transformants has surprisingly led to detecting the inheritability of tPA. There are several factors lead to silencing of transgene in transgenic plants which should be considered. Possible reasons for these silencing are like vector designing, methylation, copy number, and genome rearrangement.

  7. Chemical analysis by nuclear methods. v. 2

    International Nuclear Information System (INIS)

    Alfassi, Z.B.

    1998-01-01

    'Chemical analysis by Nuclear Methods' is an effort of some renowned authors in field of nuclear chemistry and radiochemistry which is compiled by Alfassi, Z.B. and translated into Farsi version collected in two volumes. The second volume consists of the following chapters: Detecting ion recoil scattering and elastic scattering are dealt in the eleventh chapter, the twelfth chapter is devoted to nuclear reaction analysis using charged particles, X-ray emission is discussed at thirteenth chapter, the fourteenth chapter is about using ion microprobes, X-ray fluorescence analysis is discussed in the fifteenth chapter, alpha, beta and gamma ray scattering in chemical analysis are dealt in chapter sixteen, Moessbauer spectroscopy and positron annihilation are discussed in chapter seventeen and eighteen; The last two chapters are about isotope dilution analysis and radioimmunoassay

  8. The nuclear terrorist, radiological, biological, chemical threat. Medical approach

    International Nuclear Information System (INIS)

    Gourmelon, P.; Vidal, D.; Renaudeau, C.

    2005-01-01

    This book illustrates the cooperation of the civil and the military experts in the domain of the NBRC (nuclear, biological, radiological and chemical threat). The different aspects bond to the use of nuclear, biological and chemical weapons, are discussed. Al topics of each domains (NRBC) are presented: historical and fundamental aspects, diagnostic, therapeutic and prevention. (A.L.B.)

  9. Qualification test of chemical cleaning for secondary side of steam generator in Qinshan Nuclear Power Plant

    International Nuclear Information System (INIS)

    Zhang Mengqin; Zhang Shufeng; Yu Jinghua; Hou Shufeng

    1997-07-01

    The chemical cleaning technique for removing sludge on the secondary side in Qinshan Nuclear Power Plant has been qualified. The chemical cleaning process will carry out during shutdown refuelling. The qualification test has studied the effect of chemical cleaning agent component, cleaning time on dissolution effectiveness of sludge (Fe 3 O 4 ) and to evaluate corrosion situation of main materials of SG in the cleaning process. The main component of cleaning agent is EDTA. The cleaning temperature is 20∼30 degree C. It is determined that allowable remains amount of cleaning agent (EDTA). The technique of cleaning, rinse, passivation for the chemical cleaning in Qinshan Nuclear Power Plant has been made. The qualification test shown that the technique can dissolve Fe 3 O 4 >1 g/L, the corrosion of materials is in allowable value, the allowable remains of EDTA is <0.01%. The technique character is static, ambient temperature. (9 refs., 12 tabs.)

  10. Investigations on the optimum design of chemical addition system for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Byong Hoon [Junior College of Inchon, Inchon (Korea, Republic of); Chung, Chang Kyu; Choi, Han Rim; Kim, Eun Kee; Ro, Tae Sun [Korea Power Engineering Company, Inc. Taejon (Korea, Republic of)

    1998-12-31

    Mixing characteristics of the chemical additives in the chemical injection tank of the chemical and volume control system(CVCS) were investigated for the Yonggwang Nuclear units 5 and 6. Numerical calculations were performed with a low-Reynolds number turbulence model. Studies were also conducted for the injection tank with a disk located at 1/4H, 2/4H, and 3/4H from the inlet in order to see the effect in the enhancement of chemical mixing. Results show that the optimum arrangement is to locate a disk close to the inlet. 10 refs., 4 figs. (Author)

  11. Investigations on the optimum design of chemical addition system for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Byong Hoon [Junior College of Inchon, Inchon (Korea, Republic of); Chung, Chang Kyu; Choi, Han Rim; Kim, Eun Kee; Ro, Tae Sun [Korea Power Engineering Company, Inc. Taejon (Korea, Republic of)

    1997-12-31

    Mixing characteristics of the chemical additives in the chemical injection tank of the chemical and volume control system(CVCS) were investigated for the Yonggwang Nuclear units 5 and 6. Numerical calculations were performed with a low-Reynolds number turbulence model. Studies were also conducted for the injection tank with a disk located at 1/4H, 2/4H, and 3/4H from the inlet in order to see the effect in the enhancement of chemical mixing. Results show that the optimum arrangement is to locate a disk close to the inlet. 10 refs., 4 figs. (Author)

  12. Combining chemical and electric-nuclear propulsion for high speed flight

    International Nuclear Information System (INIS)

    Murthy, S.N.B.; Froning, H.D.

    1991-01-01

    In the development of propulsion for the high speed (greater than Mach 8) regime of a SSTO vehicle, an alternative to a combination of scramjets and conventional chemical rockets is a nuclear system such as the dense plasma fusion engine operated with aneutronic fuels. Several variants are then possible in the manner of energizing the working fluid. An attempt has been made to compare the effectiveness of nuclear and scramjet engines with respect to weights and utilization of energy availability. It is shown that nuclear engines can be as effective as the optimized combustion engines, and will yield a considerable reduction in GTOW in earth-based missions, and have a special use in other planetary atmospheres in which combustion may be difficult but collection and processing of working fluid is feasible. 9 refs

  13. Understanding the chemical and structural transformations of lignin macromolecule during torrefaction

    International Nuclear Information System (INIS)

    Wen, Jia-Long; Sun, Shao-Long; Yuan, Tong-Qi; Xu, Feng; Sun, Run-Cang

    2014-01-01

    Highlights: • The terrified bamboo has a high energy yield of 85.7% and a HHV of 20.13 MJ/kg. • The structural changes of hemicelluloses, cellulose, and lignin were investigated. • First study on the structural transformations of lignin during torrefaction. • The mechanism of structural changes of lignin has been proposed. - Abstract: Torrefaction is an efficient method to recover energy from biomass. Herein, the characteristics (mass yield, energy yield, physical, and chemical characteristics) of torrefied bamboo at diverse temperatures (200–300 °C) were firstly evaluated by elemental analysis, XRD, and CP–MAS 13 C NMR methodologies. Under an optimal condition the terrified bamboo has a relative high energy yield of 85.7% and a HHV of 20.13 MJ/kg. The chemical and structural transformations of lignin induced by thermal treatment were thoroughly investigated by FT-IR and solution-state NMR techniques (quantitative 13 C NMR, 2D-HSQC, and 31 P-NMR methodologies). The results highlighted the chemical reactions of the native bamboo lignins towards severe torrefaction treatments occurred, such as depolymerization, demethoxylation, bond cleavage, and condensation reactions. NMR results indicated that aryl-ether bonds (β-O-4) and p-coumaric ester in lignin were cleaved during the torrefaction process at mild conditions. The severe treatments of bamboo (275 °C and 300 °C) induced a dramatic enrichment in lignin content together with the almost complete disappearance of β-O-4, β-β, and β-5 linkages. Further analysis of the molecular weight of milled wood lignin (MWL) indicated that the average molecular weights of “torrefied MWL” were lower than those of control MWL. It is believed that understanding of the reactivity and chemical transformations of lignin during torrefaction will contribute to the integrated torrefaction mechanism

  14. The application of nuclear energy to the Canadian chemical process industry

    International Nuclear Information System (INIS)

    Robertson, R.F.S.

    1976-03-01

    A study has been made to determine what role nuclear energy, either electrical or thermal, could play in the Canadian chemical process industry. The study was restricted to current-scale CANDU type power reactors. It is concluded that the scale of operation of the chemical industry is rarely large enough to use blocks of electrical power (e) of 500 MW or thermal power (t) of 1500 MW. Thus, with a few predictable exceptions, the role of nuclear energy in the Canadian chemical industry will be as a general thermal/electrical utility supplier, serving a variety of customers in a particular geographic area. This picture would change if nuclear steam generators of 20 to 50 MW(t) become available and are economically competitive. (author)

  15. Contaminated site investigation using nuclear technique: a case study of temporary transformer storage sites in Ghana

    International Nuclear Information System (INIS)

    Sanu, J. K.

    2013-07-01

    Recent introduction of man-made toxic chemicals, and the massive relocation of natural materials to different environmental compartment like soil, ground water and atmosphere, has resulted in severe pressure on the self- cleansing capacity of recipient ecosystems. Various accomulated pollutants and contaminants such as polychlorinated biphenyls (PCBs) are of much concern relative to both human and ecosystemm exposure and potential health impact. PCBs which are resistant to degradation and bioremediation accumulated in different niches of the biosphere. This significantly affects the ecological balances and cause adverse health effect on both human and the environment. Temporal transformer storage sites at four locations in Ghana (Tema, Temale, Bolgatanga and Wa) were investigated for PCB contamination using nuclear techniques. Analysis of soil samples from four temporal transformer storage sites revealed that the soil samples from Tema, Tamale, Bolgatanga and Wa were generally sandy with pH and EC ranging between 6.24 - 7.29 and 44.60 - 188.30 respectively. The PCB levels detected in the soil samples from the various locations varied considerably with mean ranging between 7.69 and 51.92 mg/kg. The highest mean PCB level was recorded at the Tema temporal transformer storage site (51.92 mg/kg), whilst the least mean level of 7.69 mg/kg was recorded at Wa storage site. At Tamale the individual levels range between 3.57 mg/kg and 38.70 mg/kg while at Bolgatanga it was 6.85 - 16.30 mg/kg and Wa, 6.08 - 14.70mg/kg. About 9% of soil samples from temporal transformer storage sites analysed had total PCBs concentrations above the 25mg/kg and 33 mg/kg level recommended by the Canadian Council of Ministers of environment (CCME) and EPA Ghana respectively for the protection of environment and human health. Generally, the Levels of PCBs in soil samples were found to decrease with increasing depth at all the temporal transformer storage sites. Results obtained using the EPA's L

  16. A simple and non-invasive method for nuclear transformation of intact-walled Chlamydomonas reinhardtii.

    Directory of Open Access Journals (Sweden)

    Sora Kim

    Full Text Available Genetic engineering in microalgae is gaining attraction but nuclear transformation methods available so far are either inefficient or require special equipment. In this study, we employ positively charged nanoparticles, 3-aminopropyl-functionalized magnesium phyllosilicate (aminoclay, approximate unit cell composition of [H2N(CH23]8Si8Mg6O12(OH4, for nuclear transformation into eukaryotic microalgae. TEM and EDX analysis of the process of transformation reveals that aminoclay coats negatively-charged DNA biomolecules and forms a self-assembled hybrid nanostructure. Subsequently, when this nanostructure is mixed with microalgal cells and plated onto selective agar plates with high friction force, cell wall is disrupted facilitating delivery of plasmid DNA into the cell and ultimately to the nucleus. This method is not only simple, inexpensive, and non-toxic to cells but also provides efficient transformation (5.03×10(2 transformants/µg DNA, second only to electroporation which needs advanced instrumentation. We present optimized parameters for efficient transformation including pre-treatment, friction force, concentration of foreign DNA/aminoclay, and plasticity of agar plates. It is also confirmed the successful integration and stable expression of foreign gene in Chlamydomonas reinhardtii through molecular methods.

  17. UK Chemical Nuclear Data Committee progress report

    International Nuclear Information System (INIS)

    Nichols, A.L.

    1990-01-01

    Basic nuclear data requirements for industrial application are monitored by the UK Chemical Nuclear Data Committee (UKCNDC), covering half-lives, decay data, fission yields and the content of computerised data files. While the UKCNDC Request list was reviewed at the end of 1989 to reveal new and continued requirements, funding problems have increased during the year. Difficulties in the UK nuclear power industry are reflected in the decline in experimental studies, although evaluation efforts have been maintained. (author)

  18. Inventory of chemical releases of nuclear installations in the North-Cotentin

    International Nuclear Information System (INIS)

    2002-05-01

    The nuclear installations concerned by this study are Cogema La Hague, the Flamanville nuclear power plant, the Manche plant and the National Navy of Cherbourg.The objective followed by the ' source term ' work group has consisted in counting and examining the whole of existing measures relative to the releases of chemical substances in the liquid and gaseous effluents. Then because of the lack of measures for the operation first years of installations, the work group has estimated the order of magnitude of these chemical releases (essentially for Cogema La Hague). This report presents a review of the literature looking at the background levels of chemicals in different environmental compartments: air, soil, plants and animals products. these values have been summarized here to be available for comparisons with concentrations input by the North Cotentin nuclear installations, calculated by the G.R.N.C. (radioecology group of Nord Cotentin)

  19. Environmental transformations and ecological effects of iron-based nanoparticles.

    Science.gov (United States)

    Lei, Cheng; Sun, Yuqing; Tsang, Daniel C W; Lin, Daohui

    2018-01-01

    The increasing application of iron-based nanoparticles (NPs), especially high concentrations of zero-valent iron nanoparticles (nZVI), has raised concerns regarding their environmental behavior and potential ecological effects. In the environment, iron-based NPs undergo physical, chemical, and/or biological transformations as influenced by environmental factors such as pH, ions, dissolved oxygen, natural organic matter (NOM), and biotas. This review presents recent research advances on environmental transformations of iron-based NPs, and articulates their relationships with the observed toxicities. The type and extent of physical, chemical, and biological transformations, including aggregation, oxidation, and bio-reduction, depend on the properties of NPs and the receiving environment. Toxicities of iron-based NPs to bacteria, algae, fish, and plants are increasingly observed, which are evaluated with a particular focus on the underlying mechanisms. The toxicity of iron-based NPs is a function of their properties, tolerance of test organisms, and environmental conditions. Oxidative stress induced by reactive oxygen species is considered as the primary toxic mechanism of iron-based NPs. Factors influencing the toxicity of iron-based NPs are addressed and environmental transformations play a significant role, for example, surface oxidation or coating by NOM generally lowers the toxicity of nZVI. Research gaps and future directions are suggested with an aim to boost concerted research efforts on environmental transformations and toxicity of iron-based NPs, e.g., toxicity studies of transformed NPs in field, expansion of toxicity endpoints, and roles of laden contaminants and surface coating. This review will enhance our understanding of potential risks of iron-based NPs and proper uses of environmentally benign NPs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Cell-mediated mutagenesis and cell transformation of mammalian cells by chemical carcinogens

    International Nuclear Information System (INIS)

    Huberman, E.; Langenbach, R.

    1977-01-01

    We have developed a cell-mediated mutagenesis assay in which cells with the appropriate markers for mutagenesis are co-cultivated with either lethally irradiated rodent embryonic cells that can metabolize carcinogenic hydrocarbons or with primary rat liver cells that can metabolize chemicals carcinogenic to the liver. During co-cultivation, the reactive metabolites of the procarcinogen appear to be transmitted to the mutable cells and induce mutations in them. Assays of this type make it possible to demonstrate a relationship between carcinogenic potency of the chemicals and their ability to induce mutations in mammalian cells. In addition, by simultaneously comparing the frequencies of transformation and mutation induced in normal diploid hamster cells by benzo(a)pyrene (BP) and one of its metabolites, it is possible to estimate the genetic target size for cell transformation in vitro

  1. Immunogenicity of guinea pig cells transformed in culture by chemical carcinogens.

    Science.gov (United States)

    Ohanian, S H; McCabe, R P; Evans, C H

    1981-12-01

    The immunogenicity of inbred strain 2/N guinea pig fibroblasts transformed to the malignant state in vitro by chemical carcinogens was evaluated with the use of a variety of in vivo and in vitro methods including delayed-type hypersensitivity skin and tumor transplantation tests and analysis of antibody production by immunofluorescence, complement fixation, and staphylococcal protein A binding tests. Neoplastic transformation was induced by direct treatment of cells in culture with benzo[a]pyrene, 3-methylcholanthrene, or N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) or by the host-mediated method by which fetuses were exposed to diethylnitrosamine or MNNG in vivo prior to cell culture. Rabbits and syngeneic guinea pigs were inoculated with unirradiated and X-irradiated clonally derived cells. Delayed hypersensitivity skin reactions to immunizing or other cells were equivalent in immunized or control guinea pigs, and no protection to tumor outgrowth from a challenge inoculum of immunizing cells was observed. Antibody activity induced in the sera of immunized guinea pigs was cross-reactive and removed by absorption with nontumorigenic cells. Rabbit antisera after absorption with fetal guinea pig cells were nonreactive with the specific immunizing or other culture cells. Chemical carcinogen-induced neoplastic transformation of guinea pig cells can, therefore, occur without formation of detectable, individually distinct cell surface tumor-specific neoantigens.

  2. Immunogenicity of guinea pig cells transformed in culture by chemical carcinogens

    International Nuclear Information System (INIS)

    Ohanian, S.H.; McCabe, R.P.; Evans, C.H.

    1981-01-01

    The immunogenicity of inbred strain 2/N guinea pig fibroblasts transformed to the malignant state in vitro by chemical carcinogens was evaluated with the use of a variety of in vivo and in vitro methods including delayed-type hypersensitivity skin and tumor transplantation tests and analysis of antibody production by immunofluorescence, complement fixation, and staphylococcal protein A binding tests. Neoplastic transformation was induced by direct treatment of cells in culture with benzo[a]pyrene, 3-methylcholanthrene, or N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) or by the host-mediated method by which fetuses were exposed to diethylnitrosamine or MNNG in vivo prior to cell culture. Rabbits and syngeneic guinea pigs were inoculated with unirradiated and X-irradiated clonally derived cells. Delayed hypersensitivity skin reactions to immunizing or other cells were equivalent in immunized or control guinea pigs, and no protection to tumor outgrowth from a challenge inoculum of immunizing cells was observed. Antibody activity induced in the sera of immunized guinea pigs was cross-reactive and removed by absorption with nontumorigenic cells. Rabbit anitsera after absorption with fetal guinea pig cells were nonreactive with the specific immunizing or other cultured cells. Chemical carcinogen-induced neoplastic transformation of guinea pig cells can, therefore, occur without formation of detectable, individually distinct cell surface tumor-specific neoantigens

  3. Chemical aspects of nuclear fuel fabrication processes

    Energy Technology Data Exchange (ETDEWEB)

    Naylor, A; Ellis, J F; Watson, R H

    1986-04-01

    Processes used by British Nuclear Fuels plc for the conversion of uranium ore concentrates to uranium metal and uranium hexafluoride, are reviewed. Means of converting the latter compound, after enrichment, to sintered UO/sub 2/ fuel bodies are also described. An overview is given of the associated chemical engineering technology.

  4. Laser-enhanced chemical reactions and the liquid state. II. Possible applications to nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    DePoorter, G.L.; Rofer-DePoorter, C.K.

    1976-01-01

    Laser photochemistry is surveyed as a possible improvement upon the Purex process for reprocessing spent nuclear fuel. Most of the components of spent nuclear fuel are photochemically active, and lasers can be used to selectively excite individual chemical species. The great variety of chemical species present and the degree of separation that must be achieved present difficulties in reprocessing. Lasers may be able to improve the necessary separations by photochemical reaction or effects on rates and equilibria of reactions

  5. Taking into account chemical safety for French basic nuclear installations

    International Nuclear Information System (INIS)

    Tabard, Laurence; Conte, Dorothee

    2013-01-01

    Among nuclear installations, some fuel cycle facilities present a high level of chemical hazards. In France, the TSN law of the 13 June 2006 requires taking into account all the risks generated by a basic nuclear installation (BNI). But, as most of the implementing regulatory texts are under development at this time, part of the previous regulation settled down in the 1990's is still applying: the order of the 31 December 1999 concerning technical regulation in order to prevent and to limit hazards generated by nuclear facilities; the decree of the 4 May 1995 and the order of the 26 November 1999 that deal with BNI discharges. Moreover, some parts of BNI or of nuclear sites can be submitted to the general regulation concerning chemical hazards, which is part of the environment code. As a result, even if the TSN law and its implementing decree Nr 2007-1557 of the 2 November 2007 settle clearly that safety of BNI is not only radiological, but must take into account chemical hazards, the latter aspects are still under development. Moreover the application of the existing regulation, even if complex, has helped to assess chemical risks inside BNI and nuclear sites. (authors)

  6. Characterization of the Environmentally Induced Chemical Transformations of Uranium Tetrafluoride

    Energy Technology Data Exchange (ETDEWEB)

    Wellons, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-29

    A key challenge with nuclear safeguards environmental sampling is identification of the materials post release due to subsequent chemical reactions with ambient water and oxygen. Uranium Tetrafluoride (UF4) is of interest as an intermediate in both the upstream and downstream portions of uranium feedstock and metal production processes used in nuclear fuel production; however minimal published research exists relating to UF4 hydrolysis. FY16 efforts were dedicated to in-situ Raman spectroscopy and X-ray diffraction characterization of UF4 during exposure to various relative humidity conditions. This effort mapped several hydrolysis reaction pathways and identified both intermediate, and terminal progeny species.

  7. Denaturation of collagen structures and their transformation under the physical and chemical effects

    Science.gov (United States)

    Ivankin, A.; Boldirev, V.; Fadeev, G.; Baburina, M.; Kulikovskii, A.; Vostrikova, N.

    2017-11-01

    The process of denaturation of collagen structures under the influence of physical and chemical factors play an important role in the manufacture of food technology and the production of drugs for medicine and cosmetology. The paper discussed the problem of the combined effects of heat treatment, mechanical dispersion and ultrasonic action on the structural changes of the animal collagen in the presence of weak protonated organic acids. Algorithm combined effects of physical and chemical factors as a result of the formation of the technological properties of products containing collagen has been shown.

  8. Mathematical model of phase transformations in thermo-chemical cathodes with zirconium insertion

    International Nuclear Information System (INIS)

    Kavokin, A.A.; Kazmi, I.H.

    2007-01-01

    The mathematical model of thermo-chemical processes in the cathode of plasmatron working in the gas environment is investigated. The model describes electromagnetic, temperature and concentration fields taking into account kinetic of phase transformation and chemical reaction in accordance with a state diagram. The offered approach is simpler than the Stefan's approach of describing an analogical phase transformation. As an example the case of copper cathodes with the zirconium insertion in the environment of oxygen is considered. The influence of separate parts of process on distribution of temperature inside of the insertion is estimated. On the basis of this analysis the opportunity of use of stationary approach for electric and temperature fields is shown and analytical formulas for temperature are received. After that a numerical solution for gas concentration distribution is obtained. The calculations on the specified model show that the size of area of a phase zirconium oxides depends mainly upon coefficient of diffusion of oxygen. The calculations for various types of dependencies of gas diffusion coefficient from temperature are concluded. The results of calculations develop understanding of some features of oxidation process of a zirconium insertion. Typical example of multi phase process model is the mathematical description of a heat and mass transfer occurring in metal which is being heated by an electric arch in the gas medium (1, 2, 4). The macroscopic model of physical and chemical transformations can be described as follows (3). As a metal is heated on the surface of an electrode as a function of rising results in the border dividing solid and liquid phases moves ahead deep into the electrode. At the same time there is a diffusion of gas in electrode and formation of new chemical compounds which can noticeably differ in the physical and chemical properties from each other and metal of the electrode. Moreover we shall name a phase of substance not

  9. Development of Chemical Technology in Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    Jee, Kwang Yong; Kim, W. H.; Kim, J. S.

    2007-06-01

    This project mainly concentrates on the development of technologies related to elemental analysis for the mass balance of pyro-chemical process, on the development of in-line measurement system for high temperature molten salt, and on the development of radiation shielded LA-ICP-MS and micro-XRD system to evaluate the integrity of nuclear fuel. Chemical analysis methods for the quantitative determination of fissile elements, minor actinide elements, fission products, chemical additive and corrosion products in Uranium Metal Ingots are established. It will be applied to the evaluation of mass balance in electrolytic reduction process for the optimization of the process. Optical fiber based UV-VIS spectrophotometer combined with reaction cell was developed for the measurement of reactions in high temperature molten salt. This system is applicable to in-line monitoring of electro-refining process and contribute to clarify the chemical reactions. Radiation shielded LA-ICP-MS and micro-XRD systems are planned to be used for the analysis of isotopic distribution and structural changes from core to rim of spent nuclear fuel pellet, respectively. The developed techniques can contribute to produce database needed for authorization and practical use of ultra high burn-up fuel. In addition, it can be applicable to the other industries such as microelectronics, nano material science and semiconductor to analyze micro region

  10. Chemical speciation and transformation of mercury in contaminated sediments

    OpenAIRE

    Drott, Andreas

    2009-01-01

    Biomagnification of mercury (Hg) in aquatic food webs occurs almost exclusively as mono-methyl Hg (MeHg). In this thesis, the influence of chemical speciation and environmental conditions on transformations of inorganic Hg (HgII) and MeHg was studied at eight sites in Sweden with Hg contaminated sediments. The source of contamination was either Hg0(l) or phenyl-Hg, and total Hg concentrations ranged between 1.0-1100 nmol g-1. The environmental conditions, e.g. salinity, temperature climate, p...

  11. Synergies across verification regimes: Nuclear safeguards and chemical weapons convention compliance

    International Nuclear Information System (INIS)

    Kadner, Steven P.; Turpen, Elizabeth

    2001-01-01

    In the implementation of all arms control agreements, accurate verification is essential. In setting a course for verifying compliance with a given treaty - whether the NPT or the CWC, one must make a technical comparison of existing information-gathering capabilities against the constraints in an agreement. Then it must be decided whether this level of verifiability is good enough. Generally, the policy standard of 'effective verification' includes the ability to detect significant violations, with high confidence, in sufficient time to respond effectively with policy adjustments or other responses, as needed. It is at this juncture where verification approaches have traditionally diverged. Nuclear safeguards requirements have taken one path while chemical verification methods have pursued another. However, recent technological advances have brought a number of changes affecting verification, and lately their pace has been accelerating. First, all verification regimes have more and better information as a result of new kinds of sensors, imagery, and other technologies. Second, the verification provisions in agreements have also advanced, to include on-site inspections, portal monitoring, data exchanges, and a variety of transparency, confidence-building, and other cooperative measures, Together these developments translate into a technological overlap of certain institutional verification measures such as the NPT's safeguards requirements and the IAEA and the CWC's verification visions and the OPCW. Hence, a priority of international treaty-implementing organizations is exploring the development of a synergistic and coordinated approach to WMD policy making that takes into account existing inter-linkages between nuclear, chemical, and biological weapons issues. Specific areas of coordination include harmonizing information systems and information exchanges and the shared application of scientific mechanisms, as well as collaboration on technological developments

  12. Immunofluorescent staining of nuclear antigen in lymphoid cells transformed by Herpesvirus papio (HVP).

    Science.gov (United States)

    Schmitz, H

    1981-01-01

    An improved fixation method for antigen detection in lymphoblastoid cells is described. Herpesvirus papio nuclear antigen (HUPNA) could be stained in several transformed lymphoid cell lines by anti-complement immunofluorescence (ACIF). Antibody to HUPNA was detected in many human sera containing antibodies to Epstein-Barr virus capsid and nuclear antigen (EBNA). Rheumatoid arthritis sera showed a high incidence of both anti-EBNA and anti-HUPNA antibodies.

  13. Quantum-chemical study of hydride transfer in catalytic transformation of paraffins on zeolites

    NARCIS (Netherlands)

    Kazansky, V.B.; Frash, M.V.; Santen, van R.A.; Chon, H.; Ihm, S.-K.; Uh, Y.S.

    1997-01-01

    Ab initio quantum-chemical cluster calculations demonstrate that the activated complexes of hydride transfer reaction in catalytic transformation of paraffins on zeolites very much resembles adsorbed nonclassical carbonium ions. The calculated activation energies for reactions involving propane and

  14. Interaction mechanisms of radioactive, chemical and thermal releases from the nuclear industry: Methodology for considering co-operative effects

    International Nuclear Information System (INIS)

    Streffer, C.

    1975-01-01

    A number of chemicals are known which can modify radiation effects on cell killing, carcinogenesis and mutagenesis. In this paper data are reported for radiosensitizing agents. In order to discuss the interaction mechanisms of these synergistic effects, the action of radiation on DNA, on its biological functions and on its metabolism are explained briefly. Also it is indicated that part of the radiation effects in the DNA can be 'repaired' and that living cells can recover from radiation damage. One group of radiosensitizers interacts with cellular DNA or with the DNP-complex. These reactions change the configurational structure or metabolism of DNA and DNP. In this connection the action of antibiotics such as actinomycin D, and the action of SH-blocking agents such as iodoacetamide and NEM, as well as the action of alkylating agents, are discussed. A second group of radiosensitizers, especially with hypoxic cells, are the electron affinic chemicals like nitro-compounds, ketones and others. Data are also given on the modification of radiation effects by changes in temperature. Further, the problem of whether synergistic effects are to be expected arising from the chemicals and radiation originating in the nuclear industry is considered. Data show that repair and recovery processes especially are modified by radiosensitizers. The implications of this fact on sensitization at low radiation doses and at low dose rates, as well as the effect of high LET radiation, are considered. It is of interest that the dose modifying factor of some sensitizers can reach a magnitude of a factor of two to three. (author)

  15. Digital transformation and nuclear knowledge management

    International Nuclear Information System (INIS)

    Ruiz M, F. J.

    2017-09-01

    The digital transformations that shape and condition the context in which we move are based on an apparent dichotomy between autonomy and collaboration. From this base and taking advantage of hyper connectivity phenomena, the consequences for the knowledge management in its broadest sense, and its involvement in concepts such as smart planet, are analyzed. This concept determines the evolution of organizations towards intelligent (smart) and opens conceptions that influence, in turn, a redesign of teaching-learning processes in the framework of organizations in accordance with these demands. The future bet of Tecnatom is to respond to the challenges that this situation poses in the nuclear and technological sector. (Author)

  16. Chemical cleaning the service water system at a nuclear power plant

    International Nuclear Information System (INIS)

    Brice, T.O.; Glover, W.A.

    1994-01-01

    Chemical cleaning a large cooling water system in a nuclear power plant presented many unique problems. The selection, qualification, and performance of the cleaning process were done using a phased approach. The piping was inspected to determine the extent of the problem. Deposit samples were removed from the service water system pipe and tested in the laboratory to determine the most effective cleaning solvent for deposit removal. An engineering study was performed to define the design parameters required to implement the system-wide chemical cleaning

  17. Chemical and nuclear emergencies: Interchanging lessons learned from planning and accident experience

    International Nuclear Information System (INIS)

    Adler, V.; Sorensen, J.H.; Rogers, G.O.

    1989-01-01

    Because the goal of emergency preparedness for both chemical and nuclear hazards is to reduce human exposure to hazardous materials, this paper examines the interchange of lessons learned from emergency planning and accident experience in both industries. While the concerns are slightly different, sufficient similarity is found for each to draw implications from the others experience. Principally the chemical industry can learn from the dominant planning experience associated with nuclear power plants, while the nuclear industry can chiefly learn from the chemical industry's accident experience. 23 refs

  18. Two-dimensional wavelet transform feature extraction for porous silicon chemical sensors.

    Science.gov (United States)

    Murguía, José S; Vergara, Alexander; Vargas-Olmos, Cecilia; Wong, Travis J; Fonollosa, Jordi; Huerta, Ramón

    2013-06-27

    Designing reliable, fast responding, highly sensitive, and low-power consuming chemo-sensory systems has long been a major goal in chemo-sensing. This goal, however, presents a difficult challenge because having a set of chemo-sensory detectors exhibiting all these aforementioned ideal conditions are still largely un-realizable to-date. This paper presents a unique perspective on capturing more in-depth insights into the physicochemical interactions of two distinct, selectively chemically modified porous silicon (pSi) film-based optical gas sensors by implementing an innovative, based on signal processing methodology, namely the two-dimensional discrete wavelet transform. Specifically, the method consists of using the two-dimensional discrete wavelet transform as a feature extraction method to capture the non-stationary behavior from the bi-dimensional pSi rugate sensor response. Utilizing a comprehensive set of measurements collected from each of the aforementioned optically based chemical sensors, we evaluate the significance of our approach on a complex, six-dimensional chemical analyte discrimination/quantification task problem. Due to the bi-dimensional aspects naturally governing the optical sensor response to chemical analytes, our findings provide evidence that the proposed feature extractor strategy may be a valuable tool to deepen our understanding of the performance of optically based chemical sensors as well as an important step toward attaining their implementation in more realistic chemo-sensing applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Rapid, portable detection of endocrine disrupting chemicals through ligand-nuclear hormone receptor interactions.

    Science.gov (United States)

    Hunt, J Porter; Schinn, Song-Min; Jones, Matthew D; Bundy, Bradley C

    2017-12-04

    Endocrine disrupting chemicals (EDC) are structurally diverse compounds that can interact with nuclear hormone receptors, posing significant risk to human and ecological health. Unfortunately, many conventional biosensors have been too structure-specific, labor-intensive or laboratory-oriented to detect broad ranges of EDC effectively. Recently, several technological advances are providing more rapid, portable, and affordable detection of endocrine-disrupting activity through ligand-nuclear hormone receptor interactions. Here, we overview these recent advances applied to EDC biosensors - including cell lyophilization, cell immobilization, cell-free systems, smartphone-based signal detection, and improved competitive binding assays.

  20. Fourier Transform Near Infrared Microspectroscopy, Infrared Chemical Imaging, High-Resolution Nuclear Magnetic Resonance and Fluorescence Microspectroscopy Detection of Single Cancer Cells and Single Viral Particles

    CERN Document Server

    Baianu,I C; Hofmann, N E; Korban, S S; Lozano, P; You, T

    2004-01-01

    Single Cancer Cells from Human tumors are being detected and imaged by Fourier Transform Infrared (FT-IR), Fourier Transform Near Infrared (FT-NIR)Hyperspectral Imaging and Fluorescence Correlation Microspectroscopy. The first FT-NIR chemical, microscopic images of biological systems approaching one micron resolution are here reported. Chemical images obtained by FT-NIR and FT-IR Microspectroscopy are also presented for oil in soybean seeds and somatic embryos under physiological conditions. FT-NIR spectra of oil and proteins were obtained for volumes as small as two cubic microns. Related, HR-NMR analyses of oil contents in somatic embryos as well as 99% accurate calibrations are also presented here with nanoliter precision. Such high-resolution, 400 MHz H-1 NMR analyses allowed the selection of mutagenized embryos with higher oil content (e.g. >~20%) compared to the average levels in non-mutagenized control embryos. Moreover, developmental changes in single soybean seeds and/or somatic embryos may be monito...

  1. Suppression of SOS-inducing activity of chemical mutagens by metabolites from microbial transformation of (-)-isolongifolene.

    Science.gov (United States)

    Sakata, Kazuki; Oda, Yoshimitsu; Miyazawa, Mitsuo

    2010-02-24

    In this study, biotransformation of (-)-isolongifolene (1) by Glomerella cingulata and suppressive effect on umuC gene expression by chemical mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide) and aflatoxin B(1) (AFB(1)) of the SOS response in Salmonella typhimurium TA1535/pSK1002 were investigated. Initially, 1 was carried out the microbial transformation by G. cingulata. The result found that 1 was converted into (-)-isolongifolen-9-one (2), (-)-(2S)-13-hydroxy-isolongifolen-9-one (3), and (-)-(4R)-4-hydroxy-isolongifolen-9-one (4) by G. cingulata, and their conversion rates were 60, 25, and 15%, respectively. The metabolites suppressed the SOS-inducing activity of furylfuramid and AFB(1) in the umu test. Comound 2 showed gene expression by chemical mutagens furylfuramide and AFB(1) was suppressed 54 and 50% at <0.5 mM, respectively. Compound 2 is the most effective compound in this experiment.

  2. Complete chemical transformation of a molecular film by subexcitation electrons (<3 eV).

    Science.gov (United States)

    Balog, Richard; Illenberger, Eugen

    2003-11-21

    The potential of slow electrons to act as a soft tool to control a chemical reaction in the condensed phase is demonstrated. By setting the energy of a well defined electron beam to values below 3 eV, the surface of a thin film of 1,2-C(2)F(4)C(l2) molecules can completely be transformed into molecular chlorine (and by-products, possibly perfluorinated polymers). At higher energies (>6 eV) some equilibrium state between product and educt composition can be achieved, however, accompanied by a gradual overall degradation of the film. The effect of complete transformation is based on both the selectivity and particular energy dependence of the initial step of the reaction which is dissociative electron attachment to C(2)F(4)C(l2), but also the fact that the initial molecule is efficiently decomposed by subexcitation electrons while the product C(l2) is virtually unaffected.

  3. The terrorist threat nuclear, radiological, biological, chemical - a medical approach

    International Nuclear Information System (INIS)

    Revel, M.C. de; Gourmelon, M.C.S.; Vidal, P.C.; Renaudeau, P.C.S.

    2005-01-01

    Since September 11, 2001, the fear of a large scale nuclear, biological and/or chemical terrorism is taken again into consideration at the highest level of national policies of risk prevention. The advent of international terrorism implies a cooperation between the military defense and the civil defense. The nuclear, radiological, biological and chemical (NRBC) experts of the health service of army and of civil defense will have to work together in case of major terror attack. This book presents this cooperation between civil and military experts in the NRBC domain: risk analysis, national defense plans, crisis management, syndromes and treatments. The different aspects linked with the use of nuclear, biological and chemical weapons are analyzed by the best experts from French medical and research institutes. All topics of each NRBC domain are approached: historical, basic, diagnostic, therapeutic and preventive. (J.S.)

  4. High-content image informatics of the structural nuclear protein NuMA parses trajectories for stem/progenitor cell lineages and oncogenic transformation.

    Science.gov (United States)

    Vega, Sebastián L; Liu, Er; Arvind, Varun; Bushman, Jared; Sung, Hak-Joon; Becker, Matthew L; Lelièvre, Sophie; Kohn, Joachim; Vidi, Pierre-Alexandre; Moghe, Prabhas V

    2017-02-01

    Stem and progenitor cells that exhibit significant regenerative potential and critical roles in cancer initiation and progression remain difficult to characterize. Cell fates are determined by reciprocal signaling between the cell microenvironment and the nucleus; hence parameters derived from nuclear remodeling are ideal candidates for stem/progenitor cell characterization. Here we applied high-content, single cell analysis of nuclear shape and organization to examine stem and progenitor cells destined to distinct differentiation endpoints, yet undistinguishable by conventional methods. Nuclear descriptors defined through image informatics classified mesenchymal stem cells poised to either adipogenic or osteogenic differentiation, and oligodendrocyte precursors isolated from different regions of the brain and destined to distinct astrocyte subtypes. Nuclear descriptors also revealed early changes in stem cells after chemical oncogenesis, allowing the identification of a class of cancer-mitigating biomaterials. To capture the metrology of nuclear changes, we developed a simple and quantitative "imaging-derived" parsing index, which reflects the dynamic evolution of the high-dimensional space of nuclear organizational features. A comparative analysis of parsing outcomes via either nuclear shape or textural metrics of the nuclear structural protein NuMA indicates the nuclear shape alone is a weak phenotypic predictor. In contrast, variations in the NuMA organization parsed emergent cell phenotypes and discerned emergent stages of stem cell transformation, supporting a prognosticating role for this protein in the outcomes of nuclear functions. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Nuclear magnetic resonance in pulse radiolysis. Chemically induced dynamic nuclear polarization

    International Nuclear Information System (INIS)

    Trifunac, A.D.; Johnson, K.W.; Lowers, R.H.

    1976-01-01

    Nuclear magnetic resonance and chemically induced dynamic nuclear polarization (CIDNP) were applied to the study of pulse radiolysis. Samples were irradiated with a 3-MeV electron beam from the Argonne Van de Graaff accelerator in an EPR magnet (approximately 4000 G) which had axial holes for beam access. A fast flow system transferred the irradiated solution to the rotating 5-mm NMR sample tube. The NMR spectra of mixtures of sodium acetate and methanol were presented to demonstrate the features of the CIDNP in pulse radiolysis

  6. Chemical oxidation of unsymmetrical dimethylhydrazine transformation products in water

    Directory of Open Access Journals (Sweden)

    Madi Abilev

    2015-03-01

    Full Text Available Oxidation of unsymmetrical dimethylhydrazine (UDMH during a water treatment has several disadvantages including formation of stable toxic byproducts. Effectiveness of treatment methods in relation to UDMH transformation products is currently poorly studied. This work considers the effectiveness of chemical oxidants in respect to main metabolites of UDMH – 1-formyl-2,2-dimethylhydrazine, dimethylaminoacetontrile, N-nitrosodimethylamine and 1-methyl-1H-1,2,4-triazole. Experiments on chemical oxidation by Fenton's reagent, potassium permanganate and sodium nitrite were conducted. Quantitative determination was performed by HPLC. Oxidation products were identified by gas chromatography-mass spectrometry in combination with solid-phase microextraction. 1-Formyl-2,2-dimethylhydrazine was completely oxidized by Fenton's reagent with formation of formaldehyde N-formyl-N-methyl-hydrazone, 1,4-dihydro-1,4-dimethyl-5H-tetrazol-5-one by the action of potassium permanganate and N-methyl-N-nitro-methanamine in the presence of sodium nitrite. Oxidation of 1-formyl-2,2-dimethylhydrazine also resulted in formation of N-nitrosodimethylamine. Oxidation of dimethylaminoacetontrile proceeded with formation of hydroxyacetonitrile, dimethylformamide and 1,2,5-trimethylpyrrole. After 30 days, dimethylaminoacetontrile was not detected in the presence of Fenton’s reagent and potassium permanganate, but it’s concentration in samples with sodium nitrite was 77.3 mg/L. In the presence of Fenton’s reagent, potassium permanganate and sodium nitrite after 30 days, N-nitrosodimethylamine concentration decreased by 85, 80 and 50%, respectively. In control sample, N-nitrosodimethylamine concentration decreased by 50%, indicating that sodium nitrite has no effect of on N-nitrosodimethylamine concentration. Only Fenton's reagent allowed to reduce the concentration of 1-methyl-1H-1,2,4-triazole to 50% in 30 days. In the presence of other oxidants, 1-methyl-1H-1,2,4-triazole

  7. Transformation of Nuclear Malaysia into Research and Development Organisation and Technical Support Organisation (TSO++): Restructuring Study

    International Nuclear Information System (INIS)

    Muhd Noor Muhd Yunus; Ariff Shah Ismail; Prak Tom, P.P.

    2011-01-01

    Malaysian Nuclear Agency (Nuklear Malaysia), formerly known as Malaysian Institute for Nuclear Technology Research (MINT) was established on September 1972. As an agency under the purview of Ministry of Science, Technology and Innovation (MOSTI), Nuklear Malaysia has a role to introduce and promote the application of nuclear science and technology for national development. Besides that, Nuklear Malaysia plays important role in providing quality and best-in-class research towards comprehensively generating new technologies in nuclear field. For the past few years, the government has been studying the possibility of deploying nuclear energy for electricity generation. On 11th January 2011, Y.A.B Prime Minister announced the establishment of Malaysian Nuclear Power Cooperation (MNPC) that is responsible to plan, spearhead and coordinate the implementation of nuclear energy development program for Malaysia and to take the necessary action to realize the development of the first nuclear power plant (NPP) in Malaysia. This is a strong and significant indication that Malaysia is seriously considering to embark into nuclear power program. As an agency that has been involve in nuclear field for the past few decades, Nuklear Malaysia has been identified as Technical Support Organisation (TSO) for the NPP project. Since then, preparation for transforming Nuklear Malaysia into TSO has been started. One of the areas that have been studied is the preparedness of organizations structure to effectively uphold the responsibilities of TSO. This paper briefly describes attributes of TSO, example of effective TSO organizations and study that has been conducted in preparation of Nuklear Malaysia to be Research and Development and Technical Support Organization (TSO++). (author)

  8. Quinones from plants of northeastern Brazil: structural diversity, chemical transformations, NMR data and biological activities.

    Science.gov (United States)

    Lemos, Telma L G; Monte, Francisco J Q; Santos, Allana Kellen L; Fonseca, Aluisio M; Santos, Hélcio S; Oliveira, Mailcar F; Costa, Sonia M O; Pessoa, Otilia D L; Braz-Filho, Raimundo

    2007-05-20

    The present review focus in quinones found in species of Brazilian northeastern Capraria biflora, Lippia sidoides, Lippia microphylla and Tabebuia serratifolia. The review cover ethnopharmacological aspects including photography of species, chemical structure feature, NMR datea and biological properties. Chemical transformations of lapachol to form enamine derivatives and biological activities are discussed.

  9. The Potential Pathways of Radionuclide Transformations On The Location Candidate of Nuclear Power Plants in Muria Peninsula

    International Nuclear Information System (INIS)

    Simandjuntak, A.G.; Syahrir

    1998-01-01

    The potential pathways of radionuclide transformations on the location candidate of nuclear power plants in Muria peninsula proposed to explain the potential of radionuclide pathways in the ecosystem to human based on annual effective dose calculations with elimination factor ≥ 1 of dose limit 50 mSv per year. The effective dose equivalent calculations used the program package Genll. The datum found from Bureau of Statistic Centre and NEWJEC was taken into calculations. The result of this study is very useful for radiological impact and environmental impact analysis. (author)

  10. Chemical, physical and isotopic characterization of U3Si2, for nuclear forensics purposes

    International Nuclear Information System (INIS)

    Rosa, Daniele Scarpim

    2011-01-01

    In the early 1990's, the first illicit trafficking of nuclear and radioactive materials was observed mainly in Europe. A decade marked by numerous cases of seizures of these materials. As a result, these events have become the subject of criminal forensic investigations and develop from there, nuclear forensics. In Brazil there are no illicit trafficking official records of nuclear material, however, is widely known the extraction and illegal transportation of radioactive geological materials, and the materials pieces attachment used as shielding for radioactive sources. One of the main tools used in nuclear forensics is the nuclear materials databases establishment. These documents must contain the most information as possible about the physical, chemical and nuclear material seized, allowing the identification of their origin, manufacturing process or age. Thus, it sets characteristic composition standards of each material, called 'chemical signatures' (chemical finger print). In this work nuclear forensic protocol was adopted as well as the three stages of assessment suggested by International Atomic Energy Agency (IAEA) in identifying the origin of uranium silicide (U 3 Si 2 ). Assays were performed in order to make physical, chemical and isotopic characterization of the studied materials and compared the data with those obtained for other uranium compounds (Uranium tetrafluoride, UF 4 ; uranium oxide, UO 2 and U 3 O 8 ; Yellow cake) by establishing a characteristic signature for each one. Through the assays the uranium compounds were classify by origin groups, as far as they are from different manufactured process and/ or origin. It was also possible to show the importance of a nuclear forensic database during an investigation of a nuclear forensic event. (author)

  11. Aging Management Guideline for commercial nuclear power plants: Power and distribution transformers

    International Nuclear Information System (INIS)

    Toman, G.; Gazdzinski, R.

    1994-05-01

    This Aging Management Guideline (AMG) provides recommended methods for effective detection and mitigation of age-related degradation mechanisms in power and distribution transformers important to license renewal in commercial nuclear power plants. The intent of this AMG to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner which allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein

  12. Chemical fingerprinting of Arabidopsis using Fourier transform infrared (FT-IR) spectroscopic approaches.

    Science.gov (United States)

    Gorzsás, András; Sundberg, Björn

    2014-01-01

    Fourier transform infrared (FT-IR) spectroscopy is a fast, sensitive, inexpensive, and nondestructive technique for chemical profiling of plant materials. In this chapter we discuss the instrumental setup, the basic principles of analysis, and the possibilities for and limitations of obtaining qualitative and semiquantitative information by FT-IR spectroscopy. We provide detailed protocols for four fully customizable techniques: (1) Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS): a sensitive and high-throughput technique for powders; (2) attenuated total reflectance (ATR) spectroscopy: a technique that requires no sample preparation and can be used for solid samples as well as for cell cultures; (3) microspectroscopy using a single element (SE) detector: a technique used for analyzing sections at low spatial resolution; and (4) microspectroscopy using a focal plane array (FPA) detector: a technique for rapid chemical profiling of plant sections at cellular resolution. Sample preparation, measurement, and data analysis steps are listed for each of the techniques to help the user collect the best quality spectra and prepare them for subsequent multivariate analysis.

  13. The chemical industry - a danger to nuclear power plants

    International Nuclear Information System (INIS)

    Voigtsberger, P.

    1976-01-01

    Nuclear power stations could contaminate large areas with radioactivity when destroyed by strong external influences. In Germany, authorities try to cope with this danger firstly by making certain demands on the strength of the reactor shell and secondly by imposing strict safety regulations on dangerous industrial plants in the surroundings of the reactor. In the case of chemical industry, this means: If a chemical plant and a nuclear reactor lie closely together, special stress is given to explosion pretection measures in the form of primary explosion protection, e.g. strong sealing of inflammable gases and liquids handled in the immediate neighbourhood of the reactor. (orig.) [de

  14. Chemical digestion of low level nuclear solid waste material

    International Nuclear Information System (INIS)

    Cooley, C.R.; Lerch, R.E.

    1976-01-01

    A chemical digestion for treatment of low level combustible nuclear solid waste material is provided and comprises reacting the solid waste material with concentrated sulfuric acid at a temperature within the range of 230 0 --300 0 C and simultaneously and/or thereafter contacting the reacting mixture with concentrated nitric acid or nitrogen dioxide. In a special embodiment spent ion exchange resins are converted by this chemical digestion to noncombustible gases and a low volume noncombustible residue. 6 claims, no drawings

  15. Inhibition of Neoplastic Transformation and Chemically-Induced Skin Hyperplasia in Mice by Traditional Chinese Medicinal Formula Si-Wu-Tang

    Directory of Open Access Journals (Sweden)

    Mandy M. Liu

    2017-03-01

    Full Text Available Exploring traditional medicines may lead to the development of low-cost and non-toxic cancer preventive agents. Si-Wu-Tang (SWT, comprising the combination of four herbs, Rehmanniae, Angelica, Chuanxiong, and Paeoniae, is one of the most popular traditional Chinese medicines for women’s diseases. In our previous studies, the antioxidant Nrf2 pathways were strongly induced by SWT in vitro and in vivo. Since Nrf2 activation has been associated with anticarcinogenic effects, the purpose of this study is to evaluate SWT’s activity of cancer prevention. In the Ames test, SWT demonstrated an antimutagenic activity against mutagenicity induced by the chemical carcinogen 7,12-dimethylbenz(aanthracene (DMBA. In JB6 P+ cells, a non-cancerous murine epidermal model for studying tumor promotion, SWT inhibited epidermal growth factor (EGF-induced neoplastic transformation. The luciferase reporter gene assays demonstrated that SWT suppressed EGF-induced AP-1 and TNF-α-induced NF-κB activation, which are essential factors involved in skin carcinogenesis. In a DMBA-induced skin hyperplasia assay in ‘Sensitivity to Carcinogenesis’ (SENCAR mice, both topical and oral SWT inhibited DMBA-induced epidermal hyperplasia, expression of the proliferation marker Proliferating cell nuclear antigen (PCNA, and H-ras mutations. These findings demonstrate, for the first time, that SWT prevents tumor promoter and chemical-induced carcinogenesis in vitro and in vivo, partly by inhibiting DNA damage and blocking the activation of AP-1 and NF-κB.

  16. Health and environmental effects of complex chemical mixtures: proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    The Office of Health and Environmental Research (OHER) of the Department of Energy supports a broad long-term research program on human health and environmental effects from potential exposure to energy-related complex chemical mixtures. The program seeks basic mechanistic data on the effects of complex mixtures at the cellular, molecular, and whole animal levels to aid in predicting human health effects and seeks ecological data on biological and physical transformations in the mixtures, concentrations of the mixtures in various compartments of the environment, and potential routes for human exposure to these mixtures (e.g., food chain). On June 17-18, 1985, OHER held its First Annual Technical Meeting on the Complex Chemical Mixtures Program in Chicago, IL. The primary purpose of the meeting was to enable principal investigators to report the research status and accomplishments of ongoing complex chemical mixture studies supported by OHER. To help focus future research directions round table discussions were conducted.

  17. A review of chemical decontamination systems for nuclear facilities

    International Nuclear Information System (INIS)

    Chen, L.; Chamberlain, D.B.; Conner, C.; Vandegrift, G.F.

    1996-01-01

    With the downsizing of the Department of Energy (DOE) complex, many of its buildings and facilities will be decommissioned and dismantled. As part of this decommissioning, some form of decontamination will be required. To develop an appropriate technology for in situ chemical decontamination of equipment interiors in the decommissioning of DOE nuclear facilities, knowledge of the existing chemical decontamination methods is needed. This paper attempts to give an up-to-date review of chemical decontamination methods. This survey revealed that aqueous systems are the most widely used for the decontamination and cleaning of metal surfaces. We have subdivided the aqueous systems by types of chemical solvent: acid, alkaline permanganate, highly oxidizing, peroxide, and proprietary. Two other systems, electropolishing and foams and gels, are also described in this paper

  18. Nuclear techniques in coal and chemical industries

    International Nuclear Information System (INIS)

    Elbern, A.W.; Leal, C.A.

    1980-01-01

    The use of nuclear techniques for the determination of important parameters in industrial installations is exemplified; advantages of these techniques over other methods conventionally used are pointed out. The use of radiotracers in the study of physical and chemical phenomena occurring in the chemical industry is discussed. It is also shown that, using certain radioisotopes, it is possible to construct devices which enable, for example, the determination of the ash content in coal samples. These devices are economical and easy to be installed for the on-line control during coal transportation. (C.L.B.) [pt

  19. Evaluation of thorium based nuclear fuel. Chemical aspects

    International Nuclear Information System (INIS)

    Konings, R.J.M.; Blankenvoorde, P.J.A.M.; Cordfunke, E.H.P.; Bakker, K.

    1995-07-01

    This report describes the chemical aspects of a thorium-based fuel cycle. It is part of a series devoted to the study of thorium-based fuel as a means to achieve a considerable reduction of the radiotoxicity of the waste from nuclear power production. Therefore special emphasis is placed on fuel (re-)fabrication and fuel reprocessing in the present work. (orig.)

  20. Evaluation of thorium based nuclear fuel. Chemical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Konings, R.J.M.; Blankenvoorde, P.J.A.M.; Cordfunke, E.H.P.; Bakker, K.

    1995-07-01

    This report describes the chemical aspects of a thorium-based fuel cycle. It is part of a series devoted to the study of thorium-based fuel as a means to achieve a considerable reduction of the radiotoxicity of the waste from nuclear power production. Therefore special emphasis is placed on fuel (re-)fabrication and fuel reprocessing in the present work. (orig.).

  1. Chemical metrology, strategic job for the Chilean Nuclear Energy Commission

    International Nuclear Information System (INIS)

    Gras, Nuri; Munoz, Luis; Cortes, Eduardo

    2001-01-01

    The National Standardization Institute's (INN) Metrology unit prepared a study in 1996 to evaluate the impact of metrological activity in Chile. This study was based on a survey of the supply and demand of metrological services and on studies of the behavior of the production system and technological services in Chile during the period 1990-1996. With the information obtained in this study the economic impact resulting from the lack of a national metrology system could be evaluated. This impact was estimated to be a 5% loss in gross national product equal to 125-500 million dollars because of direct product rejection in the mining, fisheries, agricultural and manufacturing sectors. Chemical measurements are responsible for 50% of these losses. In response to this need and coordinated by the INN, a metrological network of reference laboratories began to operate in 1997 for the principal physical magnitudes (mass, temperature, longitude and force) and a CORFO-FDI project began in 2001 that includes the chemical magnitudes. The Chilean Nuclear Energy Commission, aware of the problem's importance and the amount of economic damage that the country may suffer, as a result of these deficiencies, has formed a Chemical Metrology Unit to provide technical support. It aims to raise the standards of local analytical laboratories by providing international recognition to the export sector. Nuclear analytical techniques are used as reference methods. This work describes the laboratories that are included in this Chemical Metrology Unit and the historical contribution to the development of local analytical chemistry. The national and international projects are described together with the publications they have generated. The quality assurance program applied to the laboratories is described as well, which has led to the accreditation of the analytical chemical assays. The procedures used for validation and calculation of uncertain nuclear methodologies are described together with

  2. Changes of chemical properties of humic acids from crude and fungal transformed lignite

    Energy Technology Data Exchange (ETDEWEB)

    LianHua Dong; Quan Yuan; HongLi Yuan [China Agricultural University, Beijing (China). College of Biological Science

    2006-12-15

    The development of biological processes for fossil energy utilization has received increasing attention in recent years. There are abundance of lignite resources in China and the lignite, a low-grade coal, can be transformed by a Penicillium sp. After fungal transformation, the contents of humic acid and water-soluble humic material increased from 38.6% to 55.1%, and from less than 4.0% to 28.2%, respectively. The differences in chemical properties of crude lignite humic acid (aHA), fungal transformed lignite humic acid (bHA) and water-soluble humic material from fungal transformed lignite (WS) were studied. Elemental analysis and size exclusion chromatography showed that the N content of bHA increased by 47.36% compared with aHA, and the molecular mass of bHA was smaller than aHA. And the WS with the smallest molecular mass contained most content of N. The {sup 13}C NMR and FT-IR spectra of aHA and bHA showed that aHA contained more aromatic structure than bHA. 44 refs., 3 figs., 2 tabs.

  3. Sorption, Photodegradation, and Chemical Transformation of Naproxen and Ibuprofen in Soils and Water

    Science.gov (United States)

    Vulava, V. M.; Cory, W. C.; Murphey, V.; Ulmer, C.

    2015-12-01

    Trace levels of pharmaceutically active compounds (PhACs) are increasingly being found in municipal drinking water and natural streams around the world. PhACs enter natural water systems after passing through wastewater treatment plants that have proven to be relatively inefficient at removing them. Once they are released into the environment, they can undergo (1) soil sorption, (2) photodegradation, and/or (3) chemical transformation into structurally similar compounds. The overarching goal of this study is to understand the geochemical fate of common PhACs in the environment. Here we report on our studies with naproxen (NAP) and ibuprofen (IBP) in soils and water. Both compounds are complex nonpolar (aromatic) organic molecules with polar (carboxylic acid) functional groups. The carboxylic functional groups are likely to be deprotonated at environmentally relevant pHs (~4-8). Sorption studies of both compounds were conducted in clean and relatively acidic (soil pH ~4.5-6.5) natural soils that contained varying levels of organic matter (OM), clay minerals, and Fe oxides. OM was observed to play an important role in each of the above three processes. Sorption was observed to be stronger and nonlinear in higher OM soils, while weaker but still significant in lower OM, higher clay soils; the amphiphilic nature of NAP and IBP combined with the complex charged and nonpolar surfaces available in the soil was observed to control the sorption behavior. Both NAP and IBP underwent rapid photodegradation in aqueous suspensions when exposed to simulated sunlight. The degradation rates were observed to change in the presence of humic acid or fulvic acid. During sorption and photodegradation experiments, common transformation products were observed for both NAP and IBP. The transformation products produced were indicative of chemical transformation and not biological factors. Concentrations of the transformation products were significantly higher in the photoexposed aqueous

  4. Production of radionuclides and preparation of labelled compounds. Nuclear chemical technology

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    A general review is presented of methods of producing radionuclide preparations and labelled compounds, such as their production from natural raw materials, from a nuclear reactor, a particle accelerator, and using radioisotope generators. Also described are the fundamental kinetic relations of nuclear reactions. Basic methods are surveyed of obtaining labelled compounds by chemical synthesis, biosynthesis, exchange reactions, recoil reactions, by the Wilzbach method and the Szillard-Chalmers reaction. (L.K.)

  5. Isospin effects on collective nuclear dynamics

    CERN Document Server

    Di Toro, M; Baran, V; Larionov, A B

    1999-01-01

    We suggest several ways to study properties of the symmetry term in the nuclear equation of state, EOS, from collective modes in beta-unstable nuclei. After a general discussion on compressibility and saturation density in asymmetric nuclear matter we show some predictions on the collective response based on the solution of generalized Landau dispersion relations. Isoscalar-isovector coupling, disappearance of collectivity and possibility of new instabilities in low and high density regions are discussed with accent on their relation to the symmetry term of effective forces. The onset of chemical plus mechanical instabilities in a dilute asymmetric nuclear matter is discussed with reference to new features in fragmentation reactions.

  6. Differences in coupling between chemical and nuclear explosions

    International Nuclear Information System (INIS)

    Glenn, L.A.

    1992-01-01

    The teleseismic amplitude resulting from an underground explosion is proportional to the asymptotic value of the reduced displacement potential (φ∞) or, in physical terms, to the permanent change in volume measured anywhere beyond the range at which the outgoing wave has become elastic. φ∞ decreases with increasing initial cavity size (r o ) until the cavity is large enough to preclude inelastic behavior in the surrounding rock, at which point no further decrease occurs. With nuclear explosions, φ∞ can also be reduced by decreasing the initial cavity size over a certain range. This occurs because, in this range of r 0 W -1/3 (where W is the yield) the thermal pressure in the surrounding medium increases much more slowly than does the thermal energy. With chemical explosions, by contrast, r 0 W -1/3 cannot be decreased below the fully tamped limit because the energy density is bounded above. Moreover, for the most of the cavity expansion period the ratio of specific heats of the chemical explosion products is substantially higher than the equivalent ratio in a nuclear explosion, so that the cavity pressure in the former case is higher as well and this further amplifies the differences between the two. Calculations show that the teleseismic amplitude could be as much as 50% higher for an equivalent tamped chemical explosion in salt than was observed in the SALMON nuclear event

  7. Chemical Transformation System: Cloud Based Cheminformatic Services to Support Integrated Environmental Modeling

    Science.gov (United States)

    Integrated Environmental Modeling (IEM) systems that account for the fate/transport of organics frequently require physicochemical properties as well as transformation products. A myriad of chemical property databases exist but these can be difficult to access and often do not co...

  8. Effects of chemical contamination on HDPE - thermo-mechanical and characterisation properties

    International Nuclear Information System (INIS)

    Ashraf, G.

    2002-01-01

    Studying the effects of chemical contamination on HDPE is an important precursor in recycling of plastic packaging and polymer reprocessing. This research involves and discusses the results of an in-depth investigation into the effects of chemically contaminating, using various acids, commercial grade high density polyethylene (HDPE) used commonly in packaging applications. An extensive formulation study was conducted and it became obvious that in some cases degradation had occurred to HDPE when chemically contaminated with particular functional group types. The functional groups in contaminated HDPE were successfully identified. A variety of analytical techniques such as Fourier transform Infra-red spectroscopy, X-ray Florescence, x-ray photo electron spectroscopy could identify compounds such as HCl acid, HNO/sub 3/ acid and other related contaminants. Some chemical additives had effects on the mechanical and thermal properties when added in the most appropriate concentration. The results have shown lower tensile modulus and strength tensile elongation, lower modular weight, melt flow index and crystallinity. The amount of contaminant concentration, the type of chemical functional groups used and the type of test selected to affect degradation are important factors in proving the effects of chemical contamination on HDPE in the melt state. (author)

  9. The effects of climate and landscape position on chemical denudation and mineral transformation in the Santa Catalina mountain critical zone observatory

    International Nuclear Information System (INIS)

    Lybrand, Rebecca; Rasmussen, Craig; Jardine, Angie; Troch, Peter; Chorover, Jon

    2011-01-01

    Highlights: → Depth to paralithic contact generally increased with elevation. → Q/P ratios were higher in divergent landscape positions compared to adjacent convergent hollows. → Clay mineral assemblages changed as a function of elevation. → Climate, landscape position and erosion interactively control soil and regolith development. - Abstract: Understanding the interactions of climate, physical erosion, chemical weathering and pedogenic processes is essential when considering the evolution of critical zone systems. Interactions among these components are particularly important to predicting how semiarid landscapes will respond to forecasted changes in precipitation and temperature under future climate change. The primary goal of this study was to understand how climate and landscape structure interact to control chemical denudation and mineral transformation across a range of semiarid ecosystems in southern Arizona. The research was conducted along the steep environmental gradient encompassed by the Santa Catalina Mountains Critical Zone Observatory (SCM-CZO). The gradient is dominated by granitic parent materials and spans significant range in both mean annual temperature (>10 deg. C) and precipitation (>50 cm a -1 ), with concomitant shift in vegetation communities from desert scrub to mixed conifer forest. Regolith profiles were sampled from divergent and convergent landscape positions in five different ecosystems to quantify how climate-landscape position interactions control regolith development. Regolith development was quantified as depth to paralithic contact and degree of chemical weathering and mineral transformation using a combination of quantitative and semi-quantitative X-ray diffraction (XRD) analyses of bulk soils and specific particle size classes. Depth to paralithic contact was found to increase systematically with elevation for divergent positions at approximately 28 cm per 1000 m elevation, but varied inconsistently for convergent

  10. The effects of climate and landscape position on chemical denudation and mineral transformation in the Santa Catalina mountain critical zone observatory

    Energy Technology Data Exchange (ETDEWEB)

    Lybrand, Rebecca, E-mail: rlybrand@email.arizona.edu [Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 (United States); Rasmussen, Craig [Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 (United States); Jardine, Angie; Troch, Peter [Department of Hydrology and Water Resources, University of Arizona, Tucson, AZ 85721 (United States); Chorover, Jon [Department of Soil, Water and Environmental Science, University of Arizona, Tucson, AZ 85721 (United States)

    2011-06-15

    Highlights: > Depth to paralithic contact generally increased with elevation. > Q/P ratios were higher in divergent landscape positions compared to adjacent convergent hollows. > Clay mineral assemblages changed as a function of elevation. > Climate, landscape position and erosion interactively control soil and regolith development. - Abstract: Understanding the interactions of climate, physical erosion, chemical weathering and pedogenic processes is essential when considering the evolution of critical zone systems. Interactions among these components are particularly important to predicting how semiarid landscapes will respond to forecasted changes in precipitation and temperature under future climate change. The primary goal of this study was to understand how climate and landscape structure interact to control chemical denudation and mineral transformation across a range of semiarid ecosystems in southern Arizona. The research was conducted along the steep environmental gradient encompassed by the Santa Catalina Mountains Critical Zone Observatory (SCM-CZO). The gradient is dominated by granitic parent materials and spans significant range in both mean annual temperature (>10 deg. C) and precipitation (>50 cm a{sup -1}), with concomitant shift in vegetation communities from desert scrub to mixed conifer forest. Regolith profiles were sampled from divergent and convergent landscape positions in five different ecosystems to quantify how climate-landscape position interactions control regolith development. Regolith development was quantified as depth to paralithic contact and degree of chemical weathering and mineral transformation using a combination of quantitative and semi-quantitative X-ray diffraction (XRD) analyses of bulk soils and specific particle size classes. Depth to paralithic contact was found to increase systematically with elevation for divergent positions at approximately 28 cm per 1000 m elevation, but varied inconsistently for convergent

  11. A portable system for nuclear, chemical agent, and explosives identification

    International Nuclear Information System (INIS)

    Parker, W.E.; Buckley, W.M.; Kreek, S.A.; Mauger, G.J.; Lavietes, A.D.; Dougan, A.D.; Caffrey, A.J.

    2001-01-01

    The FRIS/PINS hybrid integrates the LLNL-developed Field Radionuclide Identification System (FRIS) with the INEEL-developed Portable Isotopic Neutron Spectroscopy (PINS) chemical assay system to yield a combined general radioisotope, special nuclear material, and chemical weapons/explosives detection and identification system. The PINS system uses a neutron source and a high-purity germanium γ-ray detector. The FRIS system uses an electromechanically cooled germanium detector and its own analysis software to detect and identify special nuclear material and other radioisotopes. The FRIS/PINS combined system also uses the electromechanically-cooled germanium detector. There is no other currently available integrated technology that can combine a prompt-gamma neutron-activation analysis capability for CWE with a passive radioisotope measurement and identification capability for special nuclear material

  12. A Portable System for Nuclear, Chemical Agent and Explosives Identification

    International Nuclear Information System (INIS)

    Parker, W.E.; Buckley, W.M.; Kreek, S.A.; Caffrey, A.J.; Mauger, G.J.; Lavietes, A.D.; Dougan, A.D.

    2000-01-01

    The FRIS/PINS hybrid integrates the LLNL-developed Field Radionuclide Identification System (FRIS) with the INEEL-developed Portable Isotopic Neutron Spectroscopy (PINS) chemical assay system to yield a combined general radioisotope, special nuclear material, and chemical weapons/explosives detection and identification system. The PINS system uses a neutron source and a high-purity germanium γ-ray detector. The FRIS system uses an electrochemically cooled germanium detector and its own analysis software to detect and identify special nuclear material and other radioisotopes. The FRIS/PINS combined system also uses the electromechanically-cooled germanium detector. There is no other currently available integrated technology that can combine an active neutron interrogation and analysis capability for CWE with a passive radioisotope measurement and identification capability for special nuclear material

  13. Chemical synthesis, phase transformation and magnetic proprieties of FePt and FePd nanoparticles

    International Nuclear Information System (INIS)

    Delattre, Anastasia

    2010-01-01

    This work aims at understanding the chemical synthesis of FePt and FePd nanoparticles (NPs), and at exploring how to implement the phase transformation from the chemically disordered to the L10 phase, without coalescence. Using hexadecanenitrile instead of oleylamine, we obtain NPs with a more homogenous internal composition, instead of core-shell NPs. Through a systematic study (designed experiment relying on Taguchi tables), we developed the FePd synthesis, while evidencing the role of each ligand and of the reductor. To induce the crystalline phase transformation while avoiding coalescence, we explored two ways. In the first one, atomic vacancies are introduced in the NPs through light ion irradiation, atomic mobility being ensured by annealing at moderate temperature (300 C). As a result, the blocking temperature is multiplied by 4, due to anisotropy enhancement. However, strong chemical ordering in the L10 phase cannot be achieved. The second approach relies on the dispersion of the NPs in a salt (NaCl) matrix, prior to annealing at 700 C: high chemical ordering is achieved, and the blocking temperature is beyond 400 C. We then developed a single-step process to remove the salt by dissolution in water and to re-disperse NPs in stable aqueous or organics solutions. These high magnetic anisotropy NPs are then readily available for further chemical or manipulation steps, with applied perspectives in areas such as data storage, or biology. (author)

  14. High-content image informatics of the structural nuclear protein NuMA parses trajectories for stem/progenitor cell lineages and oncogenic transformation

    International Nuclear Information System (INIS)

    Vega, Sebastián L.; Liu, Er; Arvind, Varun; Bushman, Jared; Sung, Hak-Joon; Becker, Matthew L.; Lelièvre, Sophie; Kohn, Joachim; Vidi, Pierre-Alexandre; Moghe, Prabhas V.

    2017-01-01

    Stem and progenitor cells that exhibit significant regenerative potential and critical roles in cancer initiation and progression remain difficult to characterize. Cell fates are determined by reciprocal signaling between the cell microenvironment and the nucleus; hence parameters derived from nuclear remodeling are ideal candidates for stem/progenitor cell characterization. Here we applied high-content, single cell analysis of nuclear shape and organization to examine stem and progenitor cells destined to distinct differentiation endpoints, yet undistinguishable by conventional methods. Nuclear descriptors defined through image informatics classified mesenchymal stem cells poised to either adipogenic or osteogenic differentiation, and oligodendrocyte precursors isolated from different regions of the brain and destined to distinct astrocyte subtypes. Nuclear descriptors also revealed early changes in stem cells after chemical oncogenesis, allowing the identification of a class of cancer-mitigating biomaterials. To capture the metrology of nuclear changes, we developed a simple and quantitative “imaging-derived” parsing index, which reflects the dynamic evolution of the high-dimensional space of nuclear organizational features. A comparative analysis of parsing outcomes via either nuclear shape or textural metrics of the nuclear structural protein NuMA indicates the nuclear shape alone is a weak phenotypic predictor. In contrast, variations in the NuMA organization parsed emergent cell phenotypes and discerned emergent stages of stem cell transformation, supporting a prognosticating role for this protein in the outcomes of nuclear functions. - Highlights: • High-content analysis of nuclear shape and organization classify stem and progenitor cells poised for distinct lineages. • Early oncogenic changes in mesenchymal stem cells (MSCs) are also detected with nuclear descriptors. • A new class of cancer-mitigating biomaterials was identified based on image

  15. High-content image informatics of the structural nuclear protein NuMA parses trajectories for stem/progenitor cell lineages and oncogenic transformation

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Sebastián L. [Department of Chemical and Biochemical Engineering, Rutgers University, Piscataway, NJ (United States); Liu, Er; Arvind, Varun [Department of Biomedical Engineering, Rutgers University, Piscataway, NJ (United States); Bushman, Jared [Department of Chemistry and Chemical Biology, New Jersey Center for Biomaterials, Piscataway, NJ (United States); School of Pharmacy, University of Wyoming, Laramie, WY (United States); Sung, Hak-Joon [Department of Chemistry and Chemical Biology, New Jersey Center for Biomaterials, Piscataway, NJ (United States); Department of Biomedical Engineering, Vanderbilt University, Nashville, TN (United States); Becker, Matthew L. [Department of Polymer Science and Engineering, University of Akron, Akron, OH (United States); Lelièvre, Sophie [Department of Basic Medical Sciences, Purdue University, West Lafayette, IN (United States); Kohn, Joachim [Department of Chemistry and Chemical Biology, New Jersey Center for Biomaterials, Piscataway, NJ (United States); Vidi, Pierre-Alexandre, E-mail: pvidi@wakehealth.edu [Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC (United States); Moghe, Prabhas V., E-mail: moghe@rutgers.edu [Department of Chemical and Biochemical Engineering, Rutgers University, Piscataway, NJ (United States); Department of Biomedical Engineering, Rutgers University, Piscataway, NJ (United States)

    2017-02-01

    Stem and progenitor cells that exhibit significant regenerative potential and critical roles in cancer initiation and progression remain difficult to characterize. Cell fates are determined by reciprocal signaling between the cell microenvironment and the nucleus; hence parameters derived from nuclear remodeling are ideal candidates for stem/progenitor cell characterization. Here we applied high-content, single cell analysis of nuclear shape and organization to examine stem and progenitor cells destined to distinct differentiation endpoints, yet undistinguishable by conventional methods. Nuclear descriptors defined through image informatics classified mesenchymal stem cells poised to either adipogenic or osteogenic differentiation, and oligodendrocyte precursors isolated from different regions of the brain and destined to distinct astrocyte subtypes. Nuclear descriptors also revealed early changes in stem cells after chemical oncogenesis, allowing the identification of a class of cancer-mitigating biomaterials. To capture the metrology of nuclear changes, we developed a simple and quantitative “imaging-derived” parsing index, which reflects the dynamic evolution of the high-dimensional space of nuclear organizational features. A comparative analysis of parsing outcomes via either nuclear shape or textural metrics of the nuclear structural protein NuMA indicates the nuclear shape alone is a weak phenotypic predictor. In contrast, variations in the NuMA organization parsed emergent cell phenotypes and discerned emergent stages of stem cell transformation, supporting a prognosticating role for this protein in the outcomes of nuclear functions. - Highlights: • High-content analysis of nuclear shape and organization classify stem and progenitor cells poised for distinct lineages. • Early oncogenic changes in mesenchymal stem cells (MSCs) are also detected with nuclear descriptors. • A new class of cancer-mitigating biomaterials was identified based on image

  16. Chemical durability of simulated nuclear glasses containing water

    International Nuclear Information System (INIS)

    Li, H.; Tomozawa, M.

    1995-04-01

    The chemical durability of simulated nuclear waste glasses having different water contents was studied. Results from the product consistency test (PCT) showed that glass dissolution increased with water content in the glass. This trend was not observed during MCC-1 testing. This difference was attributed to the differences in reactions between glass and water. In the PCT, the glass network dissolution controlled the elemental releases, and water in the glass accelerated the reaction rate. On the other hand, alkali ion exchange with hydronium played an important role in the MCC-1. For the latter, the amount of water introduced into a leached layer from ion-exchange was found to be much greater than that of initially incorporated water in the glass. Hence, the initial water content has no effect on glass dissolution as measured by the MCC-1 test

  17. Chemicals as the Sole Transformers of Cell Fate.

    Science.gov (United States)

    Ebrahimi, Behnam

    2016-05-30

    Forced expression of lineage-specific transcription factors in somatic cells can result in the generation of different cell types in a process named direct reprogramming, bypassing the pluripotent state. However, the introduction of transgenes limits the therapeutic applications of the produced cells. Numerous small-molecules have been introduced in the field of stem cell biology capable of governing self-renewal, reprogramming, transdifferentiation and regeneration. These chemical compounds are versatile tools for cell fate conversion toward desired outcomes. Cell fate conversion using small-molecules alone (chemical reprogramming) has superiority over arduous traditional genetic techniques in several aspects. For instance, rapid, transient, and reversible effects in activation and inhibition of functions of specific proteins are of the profits of small-molecules. They are cost-effective, have a long half-life, diversity on structure and function, and allow for temporal and flexible regulation of signaling pathways. Additionally, their effects could be adjusted by fine-tuning concentrations and combinations of different small-molecules. Therefore, chemicals are powerful tools in cell fate conversion and study of stem cell and chemical biology in vitro and in vivo. Moreover, transgene-free and chemical-only transdifferentiation approaches provide alternative strategies for the generation of various cell types, disease modeling, drug screening, and regenerative medicine. The current review gives an overview of the recent findings concerning transdifferentiation by only small-molecules without the use of transgenes.

  18. Scientific and technical conference. Problems and horizons of development of chemical and radiochemical control in nuclear energetics. Collection of summaries of reports

    International Nuclear Information System (INIS)

    2001-01-01

    During scientific and technical conference on problems of development of chemical and radiochemical control in nuclear energetics following themes were considered: the problems of methodological and instrumental assurance of chemical and radiochemical control at working nuclear power plants and nuclear energetic units; modern conceptions of automation systems construction of chemical and radiochemical control on the basis of intellectual measuring channels; the ways of decision of generally system problems of organization and management of chemical and radiochemical control using computed technologies; the problems of certification of chemical and radiochemical methods of measuring in nuclear energetics [ru

  19. Chemical, Biological, Radiological, Nuclear, and High-Yield Explosives Consequences Management

    Science.gov (United States)

    2006-10-02

    protective measures associated with such offensive operations. Since riot control agents and herbicides are not considered to be chemical warfare agents...control. Procedures to avoid, reduce, remove, or render harmless (temporarily or permanently) nuclear, radiological, biological, and chemical...destroying, neutralizing, making harmless , or removing chemical or biological agents, or by removing radioactive material clinging to or around it. (JP 1

  20. A new general methodology for incorporating physico-chemical transformations into multi-phase wastewater treatment process models.

    Science.gov (United States)

    Lizarralde, I; Fernández-Arévalo, T; Brouckaert, C; Vanrolleghem, P; Ikumi, D S; Ekama, G A; Ayesa, E; Grau, P

    2015-05-01

    This paper introduces a new general methodology for incorporating physico-chemical and chemical transformations into multi-phase wastewater treatment process models in a systematic and rigorous way under a Plant-Wide modelling (PWM) framework. The methodology presented in this paper requires the selection of the relevant biochemical, chemical and physico-chemical transformations taking place and the definition of the mass transport for the co-existing phases. As an example a mathematical model has been constructed to describe a system for biological COD, nitrogen and phosphorus removal, liquid-gas transfer, precipitation processes, and chemical reactions. The capability of the model has been tested by comparing simulated and experimental results for a nutrient removal system with sludge digestion. Finally, a scenario analysis has been undertaken to show the potential of the obtained mathematical model to study phosphorus recovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Properties of colloidal corrosion products and their effects on nuclear plants. Volume 1. Executive summary. Final report

    International Nuclear Information System (INIS)

    Matijevic, E.

    1982-10-01

    The properties of aqueous dispersions of finely divided oxides of iron, nickel, cobalt, chromium, and copper are described in overview fashion. More detailed aspects of this work will be found in a separate, larger report, NP-2606, Volume 2. The properties of these oxide corrosion products of importance to nuclear reactor water system technology are emphasized: adhesion, desorption, dissolution, transformation, and adsorption of dissolved species such as Co 60 ions. The work is fundamental to many LWR problems - radiation transport to piping surfaces, avoidance of crud buildup on nuclear fuel rods, decontamination and chemical cleaning of heat exchangers, and control of corrosion of piping

  2. Review and evaluation of the effects of xenobiotic chemicals on microorganisms in soil. [139 references

    Energy Technology Data Exchange (ETDEWEB)

    Hicks, R.J.; Van Voris, P.

    1988-02-01

    The primary objective was to review and evaluate the relevance and quality of existing xenobiotic data bases and test methods for evaluating direct and indirect effects (both adverse and beneficial) of xenobiotics on the soil microbial community; direct and indirect effects of the soil microbial community on xenobiotics; and adequacy of test methods used to evaluate these effects and interactions. Xenobiotic chemicals are defined here as those compounds, both organic and inorganic, produced by man and introduced into the environment at concentrations that cause undesirable effects. Because soil serves as the main repository for many of these chemicals, it therefore has a major role in determining their ultimate fate. Once released, the distribution of xenobiotics between environmental compartments depends on the chemodynamic properties of the compounds, the physicochemical properties of the soils, and the transfer between soil-water and soil-air interfaces and across biological membranes. Abiotic and biotic processes can transform the chemical compound, thus altering its chemical state and, subsequently, its toxicity and reactivity. Ideally, the conversion is to carbon dioxide, water, and mineral elements, or at least, to some harmless substance. However, intermediate transformation products, which can become toxic pollutants in their own right, can sometimes be formed. 139 refs., 6 figs., 11 tabs.

  3. Terrorist threat, chemical, biological, radiological, nuclear medical approach

    International Nuclear Information System (INIS)

    Revel, Th. de; Gourmelon, P.; Vidal, D.; Renaudeau, C.

    2005-01-01

    The different aspects linked to the use of nuclear, radiological, biological and or chemical weapons are gathered in this work. They concern history, fundamental aspect, diagnosis, therapy and prevention. The part devoted to the nuclear aspect concern the accidents in relation with ionizing radiations, the radiation syndrome, the contribution and limits of dosimetry, the treatment of medullary aplasia, the evaluation and treatment of an internal contamination, new perspectives on the use of cytokine for the treatment of accidental irradiated persons, alternative to the blood transfusion. (N.C.)

  4. Laboratory and Field Testing of Commercially Available Detectors for the Identification of Chemicals of Interest in the Nuclear Fuel Cycle for the Detection of Undeclared Activities

    Energy Technology Data Exchange (ETDEWEB)

    Carla Miller; Mary Adamic; Stacey Barker; Barry Siskind; Joe Brady; Warren Stern; Heidi Smartt; Mike McDaniel; Mike Stern; Rollin Lakis

    2014-07-01

    Traditionally, IAEA inspectors have focused on the detection of nuclear indicators as part of infield inspection activities. The ability to rapidly detect and identify chemical as well as nuclear signatures can increase the ability of IAEA inspectors to detect undeclared activities at a site. Identification of chemical indicators have been limited to use in the analysis of environmental samples. Although IAEA analytical laboratories are highly effective, environmental sample processing does not allow for immediate or real-time results to an IAEA inspector at a facility. During a complementary access inspection, under the Additional Protocol, the use of fieldable technologies that can quickly provide accurate information on chemicals that may be indicative of undeclared activities can increase the ability of IAEA to effectively and efficiently complete their mission. The Complementary Access Working Group (CAWG) is a multi-laboratory team with members from Brookhaven National Laboratory, Idaho National Laboratory, Los Alamos National Laboratory, and Sandia National Laboratory. The team identified chemicals at each stage of the nuclear fuel cycle that may provide IAEA inspectors with indications that proliferation activities may be occurring. The group eliminated all indicators related to equipment, technology and training, developing a list of by-products/effluents, non-nuclear materials, nuclear materials, and other observables. These proliferation indicators were prioritized based on detectability from a conduct of operations (CONOPS) perspective of a CA inspection (for example, whether an inspector actually can access the S&O or whether it is in process with no physical access), and the IAEA’s interest in the detection technology in conjunction with radiation detectors. The list was consolidated to general categories (nuclear materials from a chemical detection technique, inorganic chemicals, organic chemicals, halogens, and miscellaneous materials). The team

  5. Chemical oxidation of unsymmetrical dimethylhydrazine transformation products in water

    NARCIS (Netherlands)

    Abilev, M.; Kenessov, B.N.; Batyrbekova, S.; Grotenhuis, J.T.C.

    2015-01-01

    Oxidation of unsymmetrical dimethylhydrazine (UDMH) during a water treatment has several disadvantages including formation of stable toxic byproducts. Effectiveness of treatment methods in relation to UDMH transformation products is currently poorly studied. This work considers the effectiveness of

  6. Radiation effects in nuclear materials: Role of nuclear and electronic energy losses and their synergy

    Energy Technology Data Exchange (ETDEWEB)

    Thomé, Lionel [Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, CNRS-IN2P3-Université Paris-Sud; Debelle, Aurelien [Universite Paris Sud, Orsay, France; Garrido, Frederico [Universite Paris Sud, Orsay, France; Mylonas, Stamatis [Universite Paris Sud, Orsay, France; Décamps, B. [Universite Paris Sud, Orsay, France; Bachelet, C. [Universite Paris Sud, Orsay, France; Sattonnay, G. [LEMHE/ICMMO, Université Paris-Sud, Bât. Orsay, France; Moll, Sandra [French Atomic Energy Commission (CEA), Centre de Saclay, Gif sur Yvette; Pellegrino, S. [French Atomic Energy Commission (CEA); Miro, S. [French Atomic Energy Commission (CEA); Trocellier, P. [French Atomic Energy Commission (CEA); Serruys, Y. [French Atomic Energy Commission (CEA); Velisa, G. [French Atomic Energy Commission (CEA); Grygiel, C. [CNRS, France; Monnet, I. [CIMAP, CEA-CNRS-Université de Caen, France; Toulemonde, Marcel [French Atomic Energy Commission (CEA), French National Centre for Scientific Research (CNRS)-ENSICAE; Simon, P. [CEMHTI, CNRS, France; Jagielski, Jacek [Institute for Electronic Materials Technology; Jozwik-Biala, Iwona [Institute for Electronic Materials Technology; Nowicki, Lech [Soltan Institute for Nuclear Studies, Swierk, Poland; Behar, M. [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Porto Alegre,; Weber, William J [ORNL; Zhang, Yanwen [ORNL; Backman, Marie [University of Tennessee, Knoxville (UTK); Nordlund, Kai [University of Helsinki; Djurabekova, Flyura [University of Helsinki

    2013-01-01

    Ceramic oxides and carbides are promising matrices for the immobilization and/or transmutation of nuclear wastes, cladding materials for gas-cooled fission reactors and structural components for fusion reactors. For these applications there is a need of fundamental data concerning the behavior of nuclear ceramics upon irradiation. This article is focused on the presentation of a few remarkable examples regarding ion-beam modifications of nuclear ceramics with an emphasis on the mechanisms leading to damage creation and phase transformations. Results obtained by combining advanced techniques (Rutherford backscattering spectrometry and channeling, X-ray diffraction, transmission electron microscopy, Raman spectroscopy) concern irradiations in a broad energy range (from keV to GeV) with the aim of exploring both nuclear collision (Sn) and electronic excitation (Se) regimes. Finally, the daunting challenge of the demonstration of the existence of synergistic effects between Sn and Se is tackled by discussing the healing due to intense electronic energy deposition (SHIBIEC) and by reporting results recently obtained in dual-beam irradiation (DBI) experiments.

  7. Control and management of the chemical risk linked with hydrazine hydrate storage, unloading and injection across French nuclear fleet

    International Nuclear Information System (INIS)

    Spahic, Mersiha; Dzemidzic Aida; Dijoux, Michel; Pages, Danielle; Rigal, Jean-Francois; Boize, Magali

    2012-09-01

    Across the EDF nuclear fleet, the chemical risk linked with hydrazine hydrate storage, unloading and injection has received much attention in the past decades. Since 1997, continuous investigation into the substitution of dangerous and carcinogenic chemicals has been conducted and regularly updated by EDF. As a downstream user of hydrazine hydrate, EDF is concerned by REACH legislation, in force since 1 June 2007. As part of the compliance process with REACH, EDF provided its hydrazine hydrate suppliers with information regarding the uses of the chemical. This was done by the end of 2008, as per REACH deadline. On the other hand, EDF contributed throughout European Chemicals Agency consultation phase by submitting data relating to hydrazine hydrate uses across nuclear sites. The absence of a suitable hydrazine hydrate replacement product, able to satisfy the entirety of technical requirements, entails rigorous arrangements to be implemented in order to segregate the zones where use of hydrazine is made and therefore eradicate the risk to personnel regarding hydrazine effects. Consequently, a number of engineering changes and modifications are to be carried out on the chemical injection systems of 58 French nuclear power plants over the next few years as part of the EDF Hydrazine Fleet Programme. (authors)

  8. Improved biomass utilization through the use of nuclear techniques

    International Nuclear Information System (INIS)

    1988-10-01

    Biomass is a major by-product resource of agriculture and food manufacturing, but it is under-utilized as a source of food, fibre, and chemicals. Nuclear techniques provide unique tools for studies of the capabilities of micro-organisms in methane digestor operation and in the transformation of lignocellulosic materials to useful products. Nuclear techniques have also been effectively employed as mutagenic agents in the preparation of more efficient microbial strains for the conversion of biomass. This report reviews the variety and diversity of such applications with focus on the development of microbial processes to utilize agricultural wastes and by-products. The value of nuclear techniques is manifestly demonstrated in the production of efficient microbial mutant strains, in the tracing of metabolic pathways, in the monitoring of lignin degradation and also of fermenter operation. Refs, figs and tabs

  9. Study of phase transformation of U-2,5Zr-7,5Nb e U-3Zr-9Nb alloys for application in advanced nuclear fuel

    International Nuclear Information System (INIS)

    Pais, Rafael Witter Dias

    2015-01-01

    Metal fuels are relevant in the nuclear area due to the versatility of its use in the nuclear fuel cycle. Among the alloys of uranium investigated with high potential for use in nuclear power reactors, U-Zr-Nb alloys appear as an important alternative because of their superior physico-chemical and metallurgical properties. These alloys have also potential for use in nuclear testing, research and production radioisotopes of high performance nuclear reactors. Therefore, the development of these alloys is strategic since they are planned to be used in national reactors as RMB (Brazilian Multipurpose Reactor) and LABGENE (Electrical Generation Core Laboratory), currently under development in Brazil. In this work it was realized a extensive study in the scope of the manufacturing, heat treatment and phase transformations of U-2,5Zr-7,5Nb (m/m%) and U-3ZR-9NB (m/m%) fuel alloys. Ingots of both alloys were produced employing a specific methodology developed in this study. This methodology comprised the melting process in a vacuum induction furnace at high temperatures (1500 °C) and thermal-mechanical processing to break the as-cast structure. Samples with typical dimensions (17 x 7 x 2.5 mm) free from macrostructural defects were homogenized at 1000 °C in vacuum of 10 -5 torr for 17.5 hours with a 10°C/min cooling rate until to 820 °C and, subsequently, quenched in water. The samples, randomly selected, were subjected to isothermal treatment tests under different conditions of time and temperature. Isothermal treatments for transformation and retention phases were carried out in a special assembly designed for this work. After the tests, the samples were characterized by the usual phase characterization techniques with particular emphasis for the X-ray diffraction technique. In this way, the Rietveld refinement method was applied. In the case of uranium based alloys it is quite challenging due to the lack of data in the literature. In this work a strategy for the

  10. Valorization of Renewable Carbon Resources for Chemicals.

    Science.gov (United States)

    Chen, Xi; Zhang, Bin; Wang, Yunzhu; Yan, Ning

    2015-01-01

    The overuse of fossil fuels has caused an energy crisis and associated environment issues. It is desirable to utilize renewable resources for the production of chemicals. This review mainly introduces our recent work on the transformation of renewable carbon resources including the conversion of cellulose, lignin, and chitin into sustainable chemicals. Various transformation routes have been established to form value-added chemicals, and accordingly a variety of effective catalytic systems have been developed, either based on metal catalysis and/or acid-base catalysis, to enable the desired transformation.

  11. Nuclear, biological and chemical contamination survivability of Army material

    International Nuclear Information System (INIS)

    Feeney, J.J.

    1987-01-01

    Army Regulation (AR) 70-71, Nuclear, Biological and Chemical (NBC) Contamination Survivability of Army Material, published during 1984, establishes Army policy and procedures for the development and acquisition of material to ensure its survivablility and sustainability on the NBC-contaminated battlefield. This regulation defines NBC contamination as a term that includes both the individual and collective effects of residual radiological, biological, and chemical contamination. AR 70-71 applies to all mission-essential equipment within the Army. NBC contamination survivability is the capability of a system and its crew to withstand an NBC-contaminated environment, including decontamination, without losing the ability to accomplish the assigned mission. Characteristics of NBC contamination survivability are decontaminability, hardness, and compatability. These characteristics are engineering design criteria which are intended for use only in a developmental setting. To comply with AR 70-71, each mission-essential item must address all three criteria. The Department of Defense (DOD) has published a draft instruction addressing acquisition of NBC contamination survivable systems. This instruction will apply throughout DOD to those programs, systems and subsystems designated by the Secretary of Defense as major systems acquisition programs and to those non-major systems that have potential impact on critical functions

  12. Climate risks by radioactive krypton-85 from nuclear fission. Atmospheric-electrical and air-chemical effects of ionizing radiation in the atmosphere

    International Nuclear Information System (INIS)

    Kollert, R.

    1994-01-01

    The study shows that krypton-85 from nuclear fission enhances air ionization and, thus, interferes with the atmospheric-electrical system and the water balance of the earth atmosphere. This is reason for concern: There are unforeseeable effects for weather and climate if the krypton-85 content of the earth atmosphere continues to rise. There may be a krypton-specific greenhouse effect and a collapse of the natural atmospheric-electrical field. In addition, human well-being may be expected to be impaired as a result of the diminished atmospheric-electrical field. There is also the risk of radiochemical actions and effects caused-by krypton-85-containing plumes in other air-borne pollutants like the latters' transformation to aggressive oxidants. This implies radiation smog and more acid rain in the countries exposed. This study summarizes findings gained in these issues by various sciences, analyses them and elaborates hypotheses on the actions and effects of krypton-85 on the air, the atmosphere and the climate. (orig./HP) [de

  13. Thermochemical modeling of nuclear fuel and the effects of oxygen potential buffers

    Energy Technology Data Exchange (ETDEWEB)

    Loukusa, Henri, E-mail: henri.loukusa@vtt.fi; Ikonen, Timo; Valtavirta, Ville; Tulkki, Ville

    2016-12-01

    The elemental and chemical composition of nuclear fuel pellets are key factors influencing the material properties of the pellets. The oxidation state of the fuel is one of the most important chemical properties influencing the material properties of the fuel, and it can only be determined with the knowledge of the chemical composition. A measure of the oxidation state is the oxygen chemical potential of the fuel. It can be buffered by redox pairs, such as the well-known Mo/MoO{sub 2} pair. In this work, the elemental composition of the fuel is obtained from a burnup calculation and the temperature and pressure calculated with a fuel performance code. An estimate of the oxygen potential of fuel is calculated with Gibbs energy minimization. The results are compared against experimental data from the literature. The significance of the UMoO{sub 6} compound and its buffering effect on the oxygen potential is emphasized. - Highlights: • A Gibbs energy minimization routine has been developed for nuclear fuel modeling. • The initial stoichiometry affects the development of the oxygen potential of fuel. • UMoO{sub 6} is found to buffer the oxygen potential of nuclear fuel.

  14. Environmental parameters of the Tennessee River in Alabama. 2: Physical, chemical, and biological parameters. [biological and chemical effects of thermal pollution from nuclear power plants on water quality

    Science.gov (United States)

    Rosing, L. M.

    1976-01-01

    Physical, chemical and biological water quality data from five sites in the Tennessee River, two in Guntersville Reservoir and three in Wheeler Reservoir were correlated with climatological data for three annual cycles. Two of the annual cycles are for the years prior to the Browns Ferry Nuclear Power Plant operations and one is for the first 14 months of Plant operations. A comparison of the results of the annual cycles indicates that two distinct physical conditions in the reservoirs occur, one during the warm months when the reservoirs are at capacity and one during the colder winter months when the reservoirs have been drawn-down for water storage during the rainy months and for weed control. The wide variations of physical and chemical parameters to which the biological organisms are subjected on an annual basis control the biological organisms and their population levels. A comparison of the parameters of the site below the Power plant indicates that the heated effluent from the plant operating with two of the three reactors has not had any effect on the organisms at this site. Recommendations given include the development of prediction mathematical models (statistical analysis) for the physical and chemical parameters under specific climatological conditions which affect biological organisms. Tabulated data of chemical analysis of water and organism populations studied is given.

  15. Chemical Plant Accidents in a Nuclear Hydrogen Generation Scheme

    International Nuclear Information System (INIS)

    Brown, Nicholas R.; Revankar, Shripad T.

    2011-01-01

    A high temperature nuclear reactor (HTR) could be used to drive a steam reformation plant, a coal gasification facility, an electrolysis plant, or a thermochemical hydrogen production cycle. Most thermochemical cycles are purely thermodynamic, and thus achieve high thermodynamic efficiency. HTRs produce large amounts of heat at high temperature (1100 K). Helium-cooled HTRs have many passive, or inherent, safety characteristics. This inherent safety is due to the high design basis limit of the maximum fuel temperature. Due to the severity of a potential release, containment of fission products is the single most important safety issue in any nuclear reactor facility. A HTR coupled to a chemical plant presents a complex system, due primarily to the interactive nature of both plants. Since the chemical plant acts as the heat sink for the nuclear reactor, it important to understand the interaction and feedback between the two systems. Process heat plants and HTRs are generally very different. Some of the major differences include: time constants of plants, safety standards, failure probability, and transient response. While both the chemical plant and the HTR are at advanced stages of testing individually, no serious effort has been made to understand the operation of the integrated system, especially during accident events that are initiated in the chemical plant. There is a significant lack of knowledge base regarding scaling and system integration for large scale process heat plants coupled to HTRs. Consideration of feedback between the two plants during time-dependent scenarios is absent from literature. Additionally, no conceptual studies of the accidents that could occur in either plant and impact the entire coupled system are present in literature

  16. Radiation Effects in Nuclear Waste Materials

    International Nuclear Information System (INIS)

    Weber, William J.; Wang, Lumin; Hess, Nancy J.; Icenhower, Jonathan P.; Thevuthasan, Suntharampillai

    2003-01-01

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials. This work provides the underpinning science to develop improved glass and ceramic waste forms for the immobilization and disposition of high-level tank waste, excess plutonium, plutonium residues and scrap, other actinides, and other nuclear waste streams. Furthermore, this work is developing develop predictive models for the performance of nuclear waste forms and stabilized nuclear materials. Thus, the research performed under this project has significant implications for the immobilization of High-Level Waste (HLW) and Nuclear Materials, two mission areas within the Office of Environmental Management (EM). With regard to the HLW mission, this research will lead to improved understanding of radiation-induced degradation mechanisms and their effects on dissolution kinetics, as well as development of predictive models for waste form performance. In the Nuclear Materials mission, this research will lead to improvements in the understanding of radiation effects on the chemical and structural properties of materials for the stabilization and long-term storage of plutonium, highly-enriched uranium, and other actinides. The research uses plutonium incorporation, ion-beam irradiation, and electron-beam irradiation to simulate the effects of alpha decay and beta decay on relevant glasses and ceramics. The research under this project has the potential to result in improved glass and ceramic materials for the stabilization and immobilization of high-level tank waste, plutonium residues and scraps, surplus weapons plutonium, highly-enriched uranium, other actinides, and other radioactive materials

  17. Radiation Effects in Nuclear Waste Materials

    International Nuclear Information System (INIS)

    Weber, William J.

    2005-01-01

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials. This work provides the underpinning science to develop improved glass and ceramic waste forms for the immobilization and disposition of high-level tank waste, excess plutonium, plutonium residues and scrap, other actinides, and other nuclear waste streams. Furthermore, this work is developing develop predictive models for the performance of nuclear waste forms and stabilized nuclear materials. Thus, the research performed under this project has significant implications for the immobilization of High-Level Waste (HLW) and Nuclear Materials, two mission areas within the Office of Environmental Management (EM). With regard to the HLW mission, this research will lead to improved understanding of radiation-induced degradation mechanisms and their effects on dissolution kinetics, as well as development of predictive models for waste form performance. In the Nuclear Materials mission, this research will lead to improvements in the understanding of radiation effects on the chemical and structural properties of materials for the stabilization and long-term storage of plutonium, highly-enriched uranium, and other actinides. The research uses plutonium incorporation, ion-beam irradiation, and electron-beam irradiation to simulate the effects of alpha decay and beta decay on relevant glasses and ceramics. The research under this project has the potential to result in improved glass and ceramic materials for the stabilization and immobilization of high-level tank waste, plutonium residues and scraps, surplus weapons plutonium, highly-enriched uranium, other actinides, and other radioactive materials

  18. Valuation of the safety concept of the combined nuclear/chemical complex for hydrogen production with HTTR

    International Nuclear Information System (INIS)

    Verfondern, K.; Nishihara, T.

    2004-06-01

    The high-temperature engineering test reactor (HTTR) in Oarai, Japan, will be worldwide the first plant to demonstrate the production of hydrogen by applying the steam reforming process and using nuclear process heat as primary energy. Particular safety aspects for such a combined nuclear/chemical complex have to be investigated to further detail. One of these special aspects is the fire and explosion hazard associated with the presence of flammable gases including a large LNG storage tank in close vicinity to the reactor building. A special focus is laid upon the conceivable development of a detonation pressure wave and its damaging effect on the reactor building. A literature study has shown that methane is a comparatively slow reacting gas and that a methane vapor cloud in the open atmosphere or partially obstructed areas is highly unlikely to result in a detonation if inadvertently released and ignited. Various theoretical assessments and experimental studies, which have been conducted in the past and which are of significance for the HTTR-steam reforming system, include the spreading and combustion behavior of cryogenic liquids and flammable gas mixtures providing the basis of a comprehensive safety analysis of the combined nuclear/chemical facility. (orig.)

  19. Mass-independent isotope effects in chemical exchange reaction

    International Nuclear Information System (INIS)

    Nishizawa, Kazushige

    2000-01-01

    Isotope effects of some elements in chemical exchange reaction were investigated by use of liquid-liquid extraction, liquid membrane or chromatographic separation. Cyclic polyether was used for every method. All polyethers used in a series of the studies were made clear that they distinguished the isotopes not only by their nuclear masses but also by their nuclear sizes and shapes. Chromium isotopes, for example, were recognized to have enrichment factors being proportional to δ 2 > which is a parameter to show field shift or the nuclear size and shape of the isotope. It follows that the chromium isotopes are separated not by their masses but by their field shift effects. Nuclear spin also played a great role to separate odd mass number isotopes from even mass number isotopes in even atomic number elements. Contribution of the nuclear spin (I=3/2) of 53 Cr to total enrichment factor, ε 53/52 = -0.00028, for 53 Cr to 52 Cr was observed to be, ε spin = -0.0025. (author)

  20. Chemical Transformation System: Cloud Based Cheminformatic Services to Support Integrated Environmental Modeling (proceedings)

    Science.gov (United States)

    Integrated Environmental Modeling (IEM) systems that account for the fate/transport of organics frequently require physicochemical properties as well as transformation products. A myriad of chemical property databases exist but these can be difficult to access and often do not co...

  1. The plutonium: brief presentation of its nuclear, physical and chemical properties

    International Nuclear Information System (INIS)

    Madic, C.

    1993-01-01

    In this text we give a brief presentation of the nuclear properties (isotopes, isotopic composition of spent fuels, decay), of the physical properties (phase diagrams, alloys) and of the chemical properties (complexes, solvent extraction) of the plutonium

  2. Nuclear reactions and self-shielding effects of gamma-ray database for nuclear materials

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Mitsutane; Noda, Tetsuji [National Research Institute for Metals, Tsukuba, Ibaraki (Japan)

    2001-03-01

    A database for transmutation and radioactivity of nuclear materials is required for selection and design of materials used in various nuclear reactors. The database based on the FENDL/A-2.0 on the Internet and the additional data collected from several references has been developed in NRIM site of 'Data-Free-Way' on the Internet. Recently, the function predicted self-shielding effect of materials for {gamma}-ray was added to this database. The user interface for this database has been constructed for retrieval of necessary data and for graphical presentation of the relation between the energy spectrum of neutron and neutron capture cross section. It is demonstrated that the possibility of chemical compositional change and radioactivity in a material caused by nuclear reactions can be easily retrieved using a browser such as Netscape or Explorer. (author)

  3. Nuclear reactions and self-shielding effects of gamma-ray database for nuclear materials

    International Nuclear Information System (INIS)

    Fujita, Mitsutane; Noda, Tetsuji

    2001-01-01

    A database for transmutation and radioactivity of nuclear materials is required for selection and design of materials used in various nuclear reactors. The database based on the FENDL/A-2.0 on the Internet and the additional data collected from several references has been developed in NRIM site of 'Data-Free-Way' on the Internet. Recently, the function predicted self-shielding effect of materials for γ-ray was added to this database. The user interface for this database has been constructed for retrieval of necessary data and for graphical presentation of the relation between the energy spectrum of neutron and neutron capture cross section. It is demonstrated that the possibility of chemical compositional change and radioactivity in a material caused by nuclear reactions can be easily retrieved using a browser such as Netscape or Explorer. (author)

  4. Effects of radiation and chemicals on SV40 oncogenesis. Final progress report

    International Nuclear Information System (INIS)

    Coggin, J.H. Jr.

    1982-05-01

    This project is directed toward developing rapid, quantitative methods and immunologic markers which will permit the early detection of newly forming tumors induced or enhanced by x-irradiation, chemical carcinogens, viruses or combinations of the three. The projects under study in our ongoing collaborative program seek to develop the detailed understanding and precise methodology required for the early detection of embryonic antigens in transformed cells induced by the co-carcinogenic effects of viruses and low-level radiation. A new technique for assaying the earliest transformed cells appearing in a carcinogen treated population affords a unique tool for this study. Present plans involve efforts to purify embryonic determinants from fetal and transformed cells of hamsters and mice in order to define their role in the transformation process and in tumor development

  5. Reactions of charged and neutral recoil particles following nuclear transformations. Final report

    International Nuclear Information System (INIS)

    Ache, H.J.

    1980-12-01

    A summary is given of the various activities conducted as part of the research on the chemical reactions of energetic particles generated in nuclear reactions. Emphasis was on hot atom chemistry in gases and liquids. A bibliography of 110 publications published as part of the program is included

  6. High-risk facilities. Emergency management in nuclear, chemical and hazardous waste facilities

    International Nuclear Information System (INIS)

    Kloepfer, Michael

    2012-01-01

    The book on emergency management in high-risk facilities covers the following topics: Change in the nuclear policy, risk management of high-risk facilities as a constitutional problem - emergency management in nuclear facilities, operational mechanisms of risk control in nuclear facilities, regulatory surveillance responsibilities for nuclear facilities, operational mechanism of the risk control in chemical plants, regulatory surveillance responsibilities for chemical facilities, operational mechanisms of the risk control in hazardous waste facilities, regulatory surveillance responsibilities for hazardous waste facilities, civil law consequences in case of accidents in high-risk facilities, criminal prosecution in case of accidents in high-risk facilities, safety margins as site risk for emission protection facilities, national emergency management - strategic emergency management structures, warning and self-protection of the public in case of CBRN hazards including aspects of the psych-social emergency management.

  7. Selenium and vitamin E inhibit radiogenic and chemically induced transformation in vitro via different mechanisms

    International Nuclear Information System (INIS)

    Borek, C.; Ong, A.; Mason, H.; Donahue, L.; Biaglow, J.E.

    1986-01-01

    Results from in vivo and in vitro studies showing that antioxidants may act as anticarcinogens support the role of active oxygen in carcinogenesis and provide impetus for exploring the functions of dietary antioxidants in cancer prevention by using in vitro models. The authors examined the single and combined effects of selenium, a component of glutathione peroxidase, and vitamin E, a known antioxidant, on cell transformation induced in C3H/10T-1/2 cells by x-rays, benzo[a]pyrene, or tryptophan pyrolysate and on the levels of cellular scavenging systems peroxide destruction. Incubation of C3H/10T-1/2 cells with 2.5 μM Na 2 SeO 3 (selenium) or with 7 μM α-tocopherol succinate (vitamin E) 24 hr prior to exposure to x-rays or the chemical carcinogens resulted in an inhibition of transformation by each of the antioxidants with an additive-inhibitory action when the two nutrients were combined. Cellular pretreatment with selenium resulted in increased levels of cellular glutathione peroxidase, catalase, and nonprotein thiols (glutathione) and in an enhanced destruction of peroxide. The results support our earlier studies showing that free radical-mediated events play a role in radiation and chemically induced transformation. They indicate that selenium and vitamin E act alone and in additive fashion as radioprotecting and chemopreventing agents. The results further suggest that selenium confers protection in part by inducing or activating cellular free-radical scavenging systems and by enhancing peroxide breakdown while vitamin E appears to confer its protection by and alternate complementary mechanism

  8. Prospects for improved detection of chemical, biological, radiological, and nuclear threats

    Energy Technology Data Exchange (ETDEWEB)

    Wuest, Craig R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hart, Brad [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Slezak, Thomas R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2012-07-31

    Acquisition and use of Chemical, Biological, Radiological, and Nuclear (CBRN) weapons continue to be a major focus of concern form the security apparatus of nation states because of their potential for mass casualties when used by a determined adversary.

  9. Role of alkyl alcohol on viscosity of silica-based chemical gels for decontamination of highly radioactive nuclear facilities

    International Nuclear Information System (INIS)

    Choi, B. S.; Yoon, S. B.; Jung, C. H.; Lee, K. W.; Moon, J. K.

    2012-01-01

    Silica-based chemical gel for the decontamination of nuclear facilities was prepared by using fumed silica as a viscosifier, a 0.5 M Ce (IV) solution dissolved in concentrated nitric acid as a chemical decontamination agent, and tripropylene glycol butyl ether (TPGBE) as a co-viscosifier. A new effective strategy for the preparation of the chemical gel was investigated by introducing the alkyl alcohols as organic solvents to effectively dissolve the co-viscosifier. The mixture solution of the co-viscosifier and alkyl alcohols was more effective in the control of viscosity than that of the co-viscosifier only in gel. Here, the alkyl alcohols played a key role as an effective dissolution solvent for the co-viscosifier in the preparation of the chemical gel, resulting in a reducing of the amount of the co-viscosifier and gel time compared with that of the chemical gel prepared without the alkyl alcohols. It was considered that the alkyl alcohols contributed to the effective dissolution of the co-viscosifier as well as the homogeneous mixing in the formation of the gel, while the co-viscosifier in an aqueous media of the chemical decontamination agent solution showed a lower solubility. The decontamination efficiency of the chemical gels prepared in this work using a multi-channel analyzer (MCA) showed a high decontamination efficiency of over ca. 94% and ca. 92% for Co-60 and Cs-137 contaminated on surface of the stainless steel 304, respectively. (authors)

  10. Chemical sensors for nuclear industry

    International Nuclear Information System (INIS)

    Gnanasekaran, K.I.

    2012-01-01

    Development of chemical sensors for detection of gases at trace levels for applications in nuclear industry will be highlighted. The sensors have to be highly sensitive, reliable and rugged with long term stability to operate in harsh industrial environment. Semiconductor and solid electrolyte based electrochemical sensors satisfy the requirements. Physico-chemical aspects underlying the development of H 2 sensors in sodium and in cover gas circuit of the Fast breeder reactors for its smooth functioning, NH 3 and H 2 S sensors for use in Heavy water production industries and NO x sensors for spent fuel reprocessing plants will be presented. Development of oxygen sensors to monitor the oxygen level in the reactor containments and sodium sensors for detection of sodium leakages will also be discussed. The talk will focus the general aspects of identification of the sensing material for the respective analyte species, development of suitable chemical route for preparing them as fine powders, the need for configuring them in thick film or thin film geometries and their performance. Pulsed laser deposition method, an elegant technique to prepare the high quality thin films of multicomponent oxides is demonstrated for preparation of nanostructured thin films of complex oxides and its use in tailoring the morphology of the complex sensing material in the desired form by optimizing the in-situ growth conditions. (author)

  11. Identification of the chemical inventory of different paint types applied in nuclear facilities

    International Nuclear Information System (INIS)

    Sabrina Tietze; Foreman, M.R.St.J.; Ekberg, CH.H.; Chalmers University of Technology, Chemical and Biological Engineering, Goeteborg; Dongen van, B.E.

    2013-01-01

    The floors, concrete walls and many of the metal surfaces in nuclear power plant containments are coated with zinc primers or paint films to preserve the metal surfaces and simplify decontamination in the containment after the occurrence of a severe nuclear incident or accident. A chemical examination of paint films from different nuclear installations out of operation, as well as current operating ones, reveals that different types of paints are used whose composition can vary significantly. Results obtained for one type of paint at a certain nuclear site are in most cases unlikely to be comparable with sites painted with another type of paint. During normal operation and particularly during nuclear accidents, the paints will degrade under the high temperature, steam and irradiation influence. As paint and its degradation products can act as sources and depots for volatile iodine compounds, the type and aging conditions of the paint films will have a significant impact on the source term of the volatile fission product iodine. Thus, great care should be taken when extrapolating any results obtained for the interaction of radioactive iodine with one paint product to a different paint product. The main focus of the study is a comparison of the chemical profile of paint films applied in Swedish nuclear power plants. Teknopox Aqua V A, an epoxy paint recently used at Ringhals 2, and an emulsion paint used in the scrubber buildings of Ringhals 1-4 are compared with a paint film from Barsebaeck nuclear power plant unit 1 that had been aged under real reactor conditions for 20 years. In addition, two paint films, an emulsion and a gloss paint, used in an international nuclear fuel reprocessing facility, are compared with the paints from the Swedish nuclear power plants. (author)

  12. Laplace transform method in analysing the effect of amplifier parameter on identification of light charged particles with CsI(Tl) + PD (photodiodes) detector

    International Nuclear Information System (INIS)

    Wang Jinchuan; Xi Hongfei; Guo Zhongyan; Zhan Wenlong; Zhu Yongtai; Zhou Jianqun; Liu Guanhua; Su Hong

    1992-01-01

    Laplace transform method is applied to investigate the effect of the choice of amplifier parameter on identification of the light charged particles emitted from 12 C(46.7 MeV/u) + 58 Ni reaction. The significance of application of Laplace transformation method in heavy ion experimental nuclear physics is discussed as well

  13. Resonant transformation of electrostatic energy in ExB field system

    International Nuclear Information System (INIS)

    Tanizuka, Noboru

    1986-01-01

    A theoretical consideration on an effective transformation of electrostatic potential energy is given. A transformator particle is introduced with the transformation in an ExB field system. A device constant of the system is introduced comparing with some empirical, practical examples and an experimental proof of the transformation is given. Finally a nuclear fusion device plan is proposed based on the idea of the consideration. (author)

  14. Digital transformation and nuclear knowledge management; Transformacion digital y gestion del conocimiento nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz M, F. J., E-mail: fjruiz@tecnatom.es [Grupo Tecnatom, Av. Montes de Oca, 1, 28703 San Sebastian de los Reyes, Madrid (Spain)

    2017-09-15

    The digital transformations that shape and condition the context in which we move are based on an apparent dichotomy between autonomy and collaboration. From this base and taking advantage of hyper connectivity phenomena, the consequences for the knowledge management in its broadest sense, and its involvement in concepts such as smart planet, are analyzed. This concept determines the evolution of organizations towards intelligent (smart) and opens conceptions that influence, in turn, a redesign of teaching-learning processes in the framework of organizations in accordance with these demands. The future bet of Tecnatom is to respond to the challenges that this situation poses in the nuclear and technological sector. (Author)

  15. Nuclear structure with unitarily transformed two-body plus phenomenological three-body interactions

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, Anneke

    2011-02-02

    The importance of three-nucleon forces for a variety of nuclear structure phenomena is apparent in various investigations. This thesis provides a first step towards the inclusion of realistic three-nucleon forces by studying simple phenomenological threebody interactions. The Unitary Correlation Operator Method (UCOM) and the Similarity Renormalization Group (SRG) provide two different approaches to derive soft phase-shift equivalent nucleon-nucleon (NN) interactions via unitary transformations. Although their motivations are quite different the NN interactions obtained with the two methods exhibit some similarities. The application of the UCOM- or SRG-transformed Argonne V18 potential in the Hartree-Fock (HF) approximation and including the second-order energy corrections emerging from many-body perturbation theory (MBPT) reveals that the systematics of experimental ground-state energies can be reproduced by some of the interactions considering a series of closed-shell nuclei across the whole nuclear chart. However, charge radii are systematically underestimated, especially for intermediate and heavy nuclei. This discrepancy to experimental data is expected to result from neglected three-nucleon interactions. As first ansatz for a three-nucleon force, we consider a finite-range three-body interaction of Gaussian shape. Its influence on ground-state energies and charge radii is discussed in detail on the basis of HF plus MBPT calculations and shows a significant improvement in the description of experimental data. As the handling of the Gaussian three-body interaction is time-extensive, we show that it can be replaced by a regularized three-body contact interaction exhibiting a very similar behavior. An extensive study characterizes its properties in detail and confirms the improvements with respect to nuclear properties. To take into account information of an exact numerical solution of the nuclear eigenvalue problem, the No-Core Shell Model is applied to

  16. Mechanisms of radiation-induced neoplastic cell transformation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, T.C.H.; Tobias, C.A.

    1984-04-01

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table.

  17. Mechanisms of radiation-induced neoplastic cell transformation

    International Nuclear Information System (INIS)

    Yang, T.C.H.; Tobias, C.A.

    1984-04-01

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table

  18. Completion of a high efficiency ultralarge capacity three-phase transformer

    International Nuclear Information System (INIS)

    Maejima, Masaaki; Maruyama, Katsuya; Fukuda, Teruo.

    1986-01-01

    As for the boosting transformers for thermal and nuclear power stations, at present the ultralarge capacity transformers of 1000 - 1200 MVA class are the main, and particularly in nuclear power, accompanying the development of improved type BWRs and the rise of system stability, there is the tendency toward further large capacity and large size. Consequently, reflecting the recent rise of energy cost, the demand of energy conservation and the reduction of required sites heightened largely as well as the high reliability. In order to meet these demands, Hitachi Ltd. has established the technology of changing to iron machines such as ultralarge iron cores and ultralarge capacity undivided disk windings using the latest design and manufacture techniques were applied to the 525 kV, 1200 MVA transformer for No.4 plant in Fukushima No.2 Nuclear Power Station, Tokyo Electric Power Co., Inc., thus a three-phase transformer of the highest level, high efficiency and ultralarge capacity was completed. In this paper, the outline of this transformer and the test for verifying its reliability are described. The technical change of large capacity three-phase transformers, the specifications, construction, manufacture, reliability test and the effect of modification of this transformer, and the expansion of application to the next generation ultralarge capacity transformers are reported. (Kako, I.)

  19. Probabilistic safety assessment in the chemical and nuclear industries

    CERN Document Server

    Fullwood, Ralph R

    2000-01-01

    Probabilistic Safety Analysis (PSA) determines the probability and consequences of accidents, hence, the risk. This subject concerns policy makers, regulators, designers, educators and engineers working to achieve maximum safety with operational efficiency. Risk is analyzed using methods for achieving reliability in the space program. The first major application was to the nuclear power industry, followed by applications to the chemical industry. It has also been applied to space, aviation, defense, ground, and water transportation. This book is unique in its treatment of chemical and nuclear risk. Problems are included at the end of many chapters, and answers are in the back of the book. Computer files are provided (via the internet), containing reliability data, a calculator that determines failure rate and uncertainty based on field experience, pipe break calculator, event tree calculator, FTAP and associated programs for fault tree analysis, and a units conversion code. It contains 540 references and many...

  20. Probabilistic risk criteria and their application to nuclear chemical plant design

    International Nuclear Information System (INIS)

    Arthur, T.; Barnes, D.S.; Brown, M.L.; Taig, A.R.; Johnston, B.D.; Hayns, M.

    1989-01-01

    A nuclear chemical plant safety strategy is presented. The use of risk criteria in design is demonstrated by reference to a particular area of the plant. This involves the application of Probabilistic Risk Assessment (PRA) techniques. Computer programs developed by the UK Atomic Energy Authority (UKAEA) at its Safety and Reliability Directorate (SRD) are used toe valuate and analyze the resultant fault trees. the magnitude of releases are estimated and individual and societal risks determined. The paper concludes that the application of PRA to a nuclear chemical plant can be structured in such a way as to allow a designer to work to quantitative risk targets

  1. Three Mile Island Nuclear Station steam generator chemical cleaning

    International Nuclear Information System (INIS)

    Hansen, C.A.

    1992-01-01

    The Three Mile Island-1 steam generators were chemically cleaned in 1991 by the B and W Nuclear Service Co. (BWNS). This secondary side cleaning was accomplished through application of the EPRI/SGOG (Electric Power Research Institute - Steam Generator Owners Group) chemical cleaning iron removal process, followed by sludge lancing. BWNS also performed on-line corrosion monitoring. Corrosion of key steam generator materials was low, and well within established limits. Liquid waste, subsequently processed by BWNS was less than expected. 7 tabs

  2. UK chemical nuclear data committee progress report: data studies during 1989

    International Nuclear Information System (INIS)

    Nichols, A.L.

    1990-01-01

    Basic nuclear data requirements for industrial application are monitored by the UK Chemical Nuclear Data Committee (UKCNDC), covering half-lives, decay data, fission yields and the content of computerised data files. While the UKCNDC Request List was reviewed at the end of 1989 to reveal new and continued requirements, funding problems have increased during the year. Difficulties in the UK nuclear power industry are reflected in the decline in experimental studies, although evaluation efforts have been maintained. (author)

  3. The Fourier transform as a signature for chaos in nuclear energy levels

    International Nuclear Information System (INIS)

    Bybee, C.R.; Mitchell, G.E.; Shriner, J.F. Jr.

    1996-01-01

    The Fourier transform of the autocorrelation function is an alternative test to characterize level statistics. For GOE statistics there is a suppression of the Fourier transform near the origin; this correlation hole is absent for Poisson statistics. Numerical modeling has been used to quantify the method and determine the dependence of the correlation-hole area on number, density, sampling interval, and fraction of missing or spurious levels. For large N the normalized correlation-hole area is a nearly universal constant and insensitive to missing and spurious levels. However, for the smaller sample sizes typical of nuclear data, application of the FT method yields ambiguous results. (orig.)

  4. The Fourier transform as a signature for chaos in nuclear energy levels

    Energy Technology Data Exchange (ETDEWEB)

    Bybee, C.R. [North Carolina State Univ., Raleigh, NC (United States)]|[Triangle Universities Nuclear Lab., Durham, NC (United States); Mitchell, G.E. [North Carolina State Univ., Raleigh, NC (United States)]|[Triangle Universities Nuclear Lab., Durham, NC (United States); Shriner, J.F. Jr. [Tennessee Technological Univ., Cookeville (United States)

    1996-08-01

    The Fourier transform of the autocorrelation function is an alternative test to characterize level statistics. For GOE statistics there is a suppression of the Fourier transform near the origin; this correlation hole is absent for Poisson statistics. Numerical modeling has been used to quantify the method and determine the dependence of the correlation-hole area on number, density, sampling interval, and fraction of missing or spurious levels. For large N the normalized correlation-hole area is a nearly universal constant and insensitive to missing and spurious levels. However, for the smaller sample sizes typical of nuclear data, application of the FT method yields ambiguous results. (orig.)

  5. Nuclear and chemical data for life sciences

    International Nuclear Information System (INIS)

    Moumita Maiti; Indian Institute of Technology Roorkee, Roorkee, Uttarakhand

    2013-01-01

    Use of reactor produced radionuclides is popular in life sciences. However, cyclotron production of proton rich radionuclides are being more focused in recent times. These radionuclides have already gained attention in various fields, including life sciences, provided they are obtained in pure form. This article is a representative brief of our contributions in generating nuclear data for the production of proton rich radionuclides of terbium, astatine, technetium, ruthenium, cadmium, niobium, zirconium, rhenium, etc., which may have application in clinical, biological, agriculture studies or in basic research. The chemical data required to separate the product isotopes from the corresponding target matrix have been presented along with a few propositions of radiopharmaceuticals. It also emphasizes on the development of simple empirical technique, based on the nuclear reaction model analysis, to generate reliable nuclear data for the estimation of yield and angular distribution of emitted neutrons and light charged particles from light as well as heavy ion induced reactions on thick stopping targets. These data bear utmost important in radiation dosimetry. (author)

  6. Effect of Containment Spray Additives on the Chemical Effect after a Loss of Coolant Accident in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Chan; Park, Jong Woon; Lee, Guen Sung [KOREA HYDRO and NUCLEAR POWER Co., Daejeon (Korea, Republic of)

    2007-10-15

    As a part of USNRC GSI-191, evaluation of Kori Unit 1 ECCS recirculation sump performance has been carried out in 2006. The work is derived from the result of first PSR(Periodic Safety Review) of Kori Unit1. In this work, we have considered the replacement of spray additive in containment building to solve issues of GSI-191 and GL2004-02. We estimated the chemical effect of changing NaOH into TSP(Trisodium Phosphate) based on SRP(Standard Review Plan) 6.5.2. Rev.02. WCAP-16530 methodology is used to compare chemical effects of spray additive(or buffering agents). In the other side, chemical thermodynamic simulation can be utilized. Herein, the results using WCAP-16530 methodology and chemical simulation are presented.

  7. Tritium dispersion around the Angra Nuclear Power Plant: boundary simplification by Diffeomorph Conformal Transformations

    Energy Technology Data Exchange (ETDEWEB)

    Meneghetti, Andre; Bodmann, Bardo E.J.; Vilhena, Marco T. de, E-mail: andre.imef@gmail.com, E-mail: bardo.bodmann@ufrgs.br, E-mail: mtmbvilhena@gmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil)

    2017-07-01

    We present progress on research concerning dispersion of tritium around the Angra Nuclear Power Plant (Angra dos Reis, Rio de Janeiro state, Brazil). In particular, we are interested in studying how dispersion behaves in scenarios with complex orography. Our proposal is to transform a problem with curvilinear boundaries into an equivalent problem with plane parallel boundaries. We modify the coordinate system through a diffeomorph conformal transformation. Consequently, the operators of the dynamical equations change according to the additional terms from the affine connection. To de ne the transformation it is necessary to satisfy strong constraints, i.e., boundaries shall be 'smooth'. Our main purpose is to solve problems using a semi-analytical resolution. Currently, semi-analytic resolutions are applied only in problems that have domain with parallel planes. As a rst step into this direction in this work we present a numerical resolution. Even with restrictions, our model can be implemented in several situations. A at region is a particular case of a curvilinear domain and can be studied, where the height of the boundary layer above rivers, lakes, basins is typically smaller and thus implies a varying boundary layer height, for instance. Thus, even in at regions variations in the boundary layer occur, which characterizes a case of a curvilinear domain. Our specific interest is the region around the Angra Nuclear Power Plant that need a large source of water for their operation. There are several nuclear power plants worldwide, that are located in mountainous regions, as for example in Japan and Brazil. As one step into a new direction we focus in this work on complex relieves. We present a simulation of tritium dispersion specifically in the area where the Angra 2 Nuclear Power Plant of is located and where the relief is characterized by a considerable complexity. (author)

  8. Tritium dispersion around the Angra Nuclear Power Plant: boundary simplification by Diffeomorph Conformal Transformations

    International Nuclear Information System (INIS)

    Meneghetti, Andre; Bodmann, Bardo E.J.; Vilhena, Marco T. de

    2017-01-01

    We present progress on research concerning dispersion of tritium around the Angra Nuclear Power Plant (Angra dos Reis, Rio de Janeiro state, Brazil). In particular, we are interested in studying how dispersion behaves in scenarios with complex orography. Our proposal is to transform a problem with curvilinear boundaries into an equivalent problem with plane parallel boundaries. We modify the coordinate system through a diffeomorph conformal transformation. Consequently, the operators of the dynamical equations change according to the additional terms from the affine connection. To de ne the transformation it is necessary to satisfy strong constraints, i.e., boundaries shall be 'smooth'. Our main purpose is to solve problems using a semi-analytical resolution. Currently, semi-analytic resolutions are applied only in problems that have domain with parallel planes. As a rst step into this direction in this work we present a numerical resolution. Even with restrictions, our model can be implemented in several situations. A at region is a particular case of a curvilinear domain and can be studied, where the height of the boundary layer above rivers, lakes, basins is typically smaller and thus implies a varying boundary layer height, for instance. Thus, even in at regions variations in the boundary layer occur, which characterizes a case of a curvilinear domain. Our specific interest is the region around the Angra Nuclear Power Plant that need a large source of water for their operation. There are several nuclear power plants worldwide, that are located in mountainous regions, as for example in Japan and Brazil. As one step into a new direction we focus in this work on complex relieves. We present a simulation of tritium dispersion specifically in the area where the Angra 2 Nuclear Power Plant of is located and where the relief is characterized by a considerable complexity. (author)

  9. Climatic effects of nuclear war

    International Nuclear Information System (INIS)

    Crutzen, P.J.

    1987-01-01

    Although considerable further research has been conducted since the writing of the Scientific Committee on Problems of the Environment (SCOPE) study, the main conclusions reached in early 1986 about the potential climatic, atmospheric, chemical, ecological, and agricultural consequences of a nuclear war are still valid, also taking into account the latest research results by Thompson and Schneider (1986). The main finding of the SCOPE study is that severe, large-scale, possibly global, climatic disturbances could result from a nuclear war in which a substantial fraction (10% or more) of the combustible materials in the NATO and Warsaw Pact nations would burn, producing several tens of million tonnes of soot. This could be caused by nuclear attacks on less than a hundred of the most important urban and industrial centres of these nations. As a consequence, it is estimated that surface temperatures might drop by more than 10 deg. C over a large fraction of the continents in the northern hemisphere and that rainfall could also be strongly reduced. These effects could last for weeks, maybe years. In many parts of the northern hemisphere agricultural productivity would be severely reduced, contributing to serious food shortages. 37 refs, 5 figs, 4 tabs

  10. Research on the chemical speciation of actinides

    International Nuclear Information System (INIS)

    Jung, Euo Chang; Park, K. K.; Cho, H. R.

    2010-04-01

    A demand for the safe and effective management of spent nuclear fuel and radioactive waste generated from nuclear power plant draws increasing attention with the growth of nuclear power industry. The objective of this project is to establish the basis of research on the actinide chemistry by using advanced laser-based highly sensitive spectroscopic systems. Researches on the chemical speciation of actinides are prerequisite for the development of technologies related to nuclear fuel cycles, especially, such as the safe management of high level radioactive wastes and the chemical examination of irradiated nuclear fuels. For supporting these technologies, laser-based spectroscopies have been performed for the chemical speciation of actinide in an aqueous solutions and the quantitative analysis of actinide isotopes in spent nuclear fuels. In this report, results on the following subjects have been summarized. (1) Development of TRLFS technology for chemical speciation of actinides, (2) Development of LIBD technology for measuring solubility of actinides, (3) Chemical speciation of plutonium complexes by using a LWCC system, (4) Development of LIBS technology for the quantitative analysis of actinides, (5) Development of technology for the chemical speciation of actinides by CE, (6) Evaluation on the chemical reactions between actinides and humic substances, (7) Chemical speciation of actinides adsorbed on metal oxides surfaces, (8) Determination of actinide source terms of spent nuclear fuel

  11. Method for the chemical reprocessing of irradiated nuclear fuels, in particular nuclear fuels containing uranium

    International Nuclear Information System (INIS)

    Koch, G.

    1976-01-01

    In the chemical processing of irradiated uranium-containing nuclear fuels which are hydrolyzed with aqueous nitric acid, a suggestion is made to use as quaternary ammonium nitrate trialkyl-methyl ammonium nitrates as extracting agent, in which the sum of C atoms is greater than 16. In the illustrated examples, tricaprylmethylammonium nitrate, trilaurylmethylammonium nitrate and tridecylmethylammonium nitrate are named. (HPH/LH) [de

  12. Chemical synthesis, redox transformation, and identification of sonnerphenolic C, an antioxidant in Acer nikoense.

    Science.gov (United States)

    Iwadate, Takehiro; Nihei, Ken-Ichi

    2017-04-15

    Sonnerphenolic C (3), which was predicted in a redox product of epirhododendrin (1) isolated from Acer nikoense, was synthesized for the first time via the epimeric separation of benzylidene acetal intermediates as a key step. From a similar synthetic route, 1 was obtained concisely. As a result of their antioxidative evaluation, only 3 revealed potent activity. The redox transformation of 1 into 3 was achieved in the presence of tyrosinase and vitamin C. Moreover, 3 was identified in the decoction of A. nikoense by HPLC analysis with the effective use of synthesized 3. Thus, a novel naturally occurring antioxidant 3 was developed through the sequential flow including redox prediction, chemical synthesis, evaluation of the activity, and identification as the natural product. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Chemical correlations in Caetite (BA) region, Brazil

    International Nuclear Information System (INIS)

    Gennari, R.F.; Almeida, Geangela M.; Souza, S.O.

    2013-01-01

    Brazil's economic situation is responsible for an urgent demand for energy. There are several ways to generate energy, in some localities of our country, energy generation occurs almost exclusively by nuclear route, as in Rio de Janeiro state. Brazil has the sixth largest reserve of the uranium ore in the world. Nowadays there is only one mine under exploration (Uraniferous District of Lagoa Real - Caetite-BA). Unfortunately, nuclear power generation is better known, by common citizen, more for its unwanted effects than for its benefits. This fact is also powered by some Non-Governmental Organizations (NGOs), such as Greenpeace, who claim the uranium mine is dangerous since it causes environmental contamination. However, Industrias Nucleares do Brasil (INB) rejected these accusations. In a previous study, we demonstrated that doses of the Caetite (BA) population are consistent with those usually found in other countries. We stated also the higher concentration of 238 U determined, in only one water sample, is probably due to natural processes, as soil leaching. In order to verify the existing natural processes, macro and micro chemical elements present in water and soil samples collected in the Caetite (BA) region were determined by ICP-MS. The results were transformed into dendrograms where chemical correlations are evidenced and they are consistent with existing natural chemical processes. It was also possible to observe a correlation between samples corroborating with the Geographic Information Systems data to be presented in this same scientific event. (author)

  14. Chemical correlations in Caetite (BA) region, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Gennari, R.F., E-mail: rgennari@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Inst. de Fisica. Dept. de Fisica Nuclear; Campos, S.S., E-mail: simaracampos@gmail.com [Universidade Estadual do Sudoeste da Bahia (UESB), Itapetinga, BA, (Brazil); Almeida, Geangela M.; Souza, S.O., E-mail: susanasouzalalic@gmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Dept. de Fisica

    2013-07-01

    Brazil's economic situation is responsible for an urgent demand for energy. There are several ways to generate energy, in some localities of our country, energy generation occurs almost exclusively by nuclear route, as in Rio de Janeiro state. Brazil has the sixth largest reserve of the uranium ore in the world. Nowadays there is only one mine under exploration (Uraniferous District of Lagoa Real - Caetite-BA). Unfortunately, nuclear power generation is better known, by common citizen, more for its unwanted effects than for its benefits. This fact is also powered by some Non-Governmental Organizations (NGOs), such as Greenpeace, who claim the uranium mine is dangerous since it causes environmental contamination. However, Industrias Nucleares do Brasil (INB) rejected these accusations. In a previous study, we demonstrated that doses of the Caetite (BA) population are consistent with those usually found in other countries. We stated also the higher concentration of {sup 238}U determined, in only one water sample, is probably due to natural processes, as soil leaching. In order to verify the existing natural processes, macro and micro chemical elements present in water and soil samples collected in the Caetite (BA) region were determined by ICP-MS. The results were transformed into dendrograms where chemical correlations are evidenced and they are consistent with existing natural chemical processes. It was also possible to observe a correlation between samples corroborating with the Geographic Information Systems data to be presented in this same scientific event. (author)

  15. Will Iran Nuclear Deal Be Effectively Implemented?

    Institute of Scientific and Technical Information of China (English)

    Li Guofu

    2016-01-01

    The fourth Nuclear Security Summit is convened in Washington DC of the US on March 31st,2016.The development and utilization of nuclear energy has brought new power for the development of human society and significantly enhanced human capability of knowing and transforming the world.However,it also brought about nuclear security risks and challenge.Particularly in today’s international political struggle,some states are making use

  16. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors

  17. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors. (Auth.)

  18. Natural radiation, nuclear wastes and chemical pollutants

    International Nuclear Information System (INIS)

    Christensen, T.; Ehdwall, H.; Stranden, E.

    1990-01-01

    Doses from natural radiation to the population in the Nordic Countries are summarized and man made modifications of the natural radiation environment are discussed. An account is given of the radiological consequences of energy conservation by reduced ventilation. Risks from possible future releases of radioactivity from final repositories of spent nuclear fuel are compared to the risks from present natural radioactivity in the environment. The possibilities for comparison between chemical and radiological risks are discussed. (author) 13 refs

  19. Investigating the Non-Covalent Functionalization and Chemical Transformation of Graphene

    Science.gov (United States)

    Sham, Chun-Hong

    Trend in device miniatures demands capabilities to produce rationally designed patterns in ever-shrinking length scale. The research community has examined various techniques to push the current lithography resolution to sub-10nm scale. One of the ideas is to utilize the natural nanoscale patterns of molecular assemblies. In this thesis, the self-assembling phenomenon of a photoactive molecule on epitaxial graphene (EG) grown on SiC was discussed. This molecular assembly enables manipulation of chemical contrast in nanoscale through UV exposure or atomic layer deposition. Future development of nanoelectronics industry will be fueled by innovations in electronics materials, which could be discovered through covalent modification of graphene. In a study reported in this thesis, silicon is deposited onto EG. After annealing, a new surface reconstruction, identified to be (3x3)-SiC, was formed. Raman spectroscopy finds no signature of graphene after annealing, indicating a complete chemical transformation of graphene. DFT calculations reveal a possible conversion mechanism. Overall, these studies provide insights for future device miniaturization; contribute to the search of novel materials and help bridging the gap between graphene and current silicon-based industrial infrastructures.

  20. Fourier transform IR studies on the interaction of selected chemicals with isolated cuticles

    International Nuclear Information System (INIS)

    Luque, P.; Ramirez, F.J.; Heredia, A.; Bukovac, M.J.

    1994-01-01

    It is known that the plant cuticle represents the first barrier that must be overcome by any chemical reaching the plant surface from the atmosphere before entering the plant. Because of the importance of the cuticle as a barrier to penetration of a wide variety of compounds, its morphology, chemistry, and permeability have been extensively studied. However, only limited information is available on the nature of functional chemical groups present and their interaction and role during the penetration process. The usefulness of in situ Fourier transform infrared spectroscopy studies in identifying functional groups present in isolated cuticles is described and their relationships to the structure of the cuticular membrane are discussed. Applications of infrared spectroscopy on the presence and role of phenolics in the cuticle structure and during the cuticle development, nitrogen oxide binding to isolated cuticles, and the interactions between selected chemical probes during sorption by the cuticle are also described. (orig.)

  1. Induction of cellular transformation by irradiation from artificial light sources

    International Nuclear Information System (INIS)

    Withrow, T.J.

    1981-01-01

    Cellular transformation in vitro has been used to test for the carcinogenic potential of chemical and physical insults including light. This report discusses the measurement of transformation, and reviews studies done on the effects of exposure to artificial light on cellular transformation or on cellular transformation by a virus. To date, cool-white lamps have been found to cause cellular transformation, while germicidal lamps and sunlamps have been found to cause cellular transformation and to enhance virally produced transformation

  2. Organic Acids Regulation of Chemical-Microbial Phosphorus Transformations in Soils.

    Science.gov (United States)

    Menezes-Blackburn, Daniel; Paredes, Cecilia; Zhang, Hao; Giles, Courtney D; Darch, Tegan; Stutter, Marc; George, Timothy S; Shand, Charles; Lumsdon, David; Cooper, Patricia; Wendler, Renate; Brown, Lawrie; Blackwell, Martin; Wearing, Catherine; Haygarth, Philip M

    2016-11-01

    We have used an integrated approach to study the mobility of inorganic phosphorus (P) from soil solid phase as well as the microbial biomass P and respiration at increasing doses of citric and oxalic acid in two different soils with contrasting agronomic P status. Citric or oxalic acids significantly increased soil solution P concentrations for doses over 2 mmol kg -1 . However, low organic acid doses (<2 mmol kg -1 ) were associated with a steep increase in microbial biomass P, which was not seen for higher doses. In both soils, treatment with the tribasic citric acid led to a greater increase in soil solution P than the dibasic oxalic acid, likely due to the rapid degrading of oxalic acids in soils. After equilibration of soils with citric or oxalic acids, the adsorbed-to-solution distribution coefficient (K d ) and desorption rate constants (k -1 ) decreased whereas an increase in the response time of solution P equilibration (T c ) was observed. The extent of this effect was shown to be both soil and organic acid specific. Our results illustrate the critical thresholds of organic acid concentration necessary to mobilize sorbed and precipitated P, bringing new insight on how the exudation of organic acids regulate chemical-microbial soil phosphorus transformations.

  3. Lunasin-aspirin combination against NIH/3T3 cells transformation induced by chemical carcinogens.

    Science.gov (United States)

    Hsieh, Chia-Chien; Hernández-Ledesma, Blanca; de Lumen, Ben O

    2011-06-01

    Carcinogenesis is a multistage process involving a number of molecular pathways sensitive to intervention. Chemoprevention is defined as the use of natural and/or synthetic substances to block, reverse, or retard the process of carcinogenesis. To achieve greater inhibitory effects on cancer cells, combination of two or more chemopreventive agents is commonly considered as a better preventive and/or therapeutic strategy. Lunasin is a promising cancer preventive peptide identified in soybean and other seeds. Its efficacy has been demonstrated by both in vitro and in vivo models. This peptide has been found to inhibit human breast cancer MDA-MB-231 cells proliferation, suppressing cell cycle progress and inducing cell apoptosis. Moreover, lunasin potentiates the effects on these cells of different synthetic and natural compounds, such as aspirin and anacardic acid. This study explored the role of lunasin, alone and in combination with aspirin and anacardic acid on cell proliferation and foci formation of transformed NIH/3T3 cells induced by chemical carcinogens 7,12-dimethylbenz[a]anthracene or 3-methylcholanthrene. The results revealed that lunasin, acting as a single agent, inhibits cell proliferation and foci formation. When combined with aspirin, these effects were significantly increased, indicating that this combination might be a promising strategy to prevent/treat cancer induced by chemical carcinogens.

  4. A nonlinear isobologram model with Box-Cox transformation to both sides for chemical mixtures.

    Science.gov (United States)

    Chen, D G; Pounds, J G

    1998-12-01

    The linear logistical isobologram is a commonly used and powerful graphical and statistical tool for analyzing the combined effects of simple chemical mixtures. In this paper a nonlinear isobologram model is proposed to analyze the joint action of chemical mixtures for quantitative dose-response relationships. This nonlinear isobologram model incorporates two additional new parameters, Ymin and Ymax, to facilitate analysis of response data that are not constrained between 0 and 1, where parameters Ymin and Ymax represent the minimal and the maximal observed toxic response. This nonlinear isobologram model for binary mixtures can be expressed as [formula: see text] In addition, a Box-Cox transformation to both sides is introduced to improve the goodness of fit and to provide a more robust model for achieving homogeneity and normality of the residuals. Finally, a confidence band is proposed for selected isobols, e.g., the median effective dose, to facilitate graphical and statistical analysis of the isobologram. The versatility of this approach is demonstrated using published data describing the toxicity of the binary mixtures of citrinin and ochratoxin as well as a new experimental data from our laboratory for mixtures of mercury and cadmium.

  5. Chemical stability of insulin. 5. Isolation, characterization and identification of insulin transformation products.

    Science.gov (United States)

    Brange, J; Hallund, O; Sørensen, E

    1992-01-01

    During storage of insulin formulated for therapy, minor amounts of various degradation and covalent di- and polymerization products are formed [1-3]. The main chemical transformation products were isolated from aged preparations and characterized chemically and biologically. The most prominent products formed in neutral medium were identified as a mixture of deamidation products hydrolyzed at residue B3, namely isoAsp B3 and Asp B3 derivatives. A hydrolysis product formed only in crystals of insulin zinc suspensions containing a surplus of zinc ions in the supernatant was identified as an A8-A9 cleavage product. The small amounts of covalent insulin dimers (CID) formed in all formulations were shown to be a heterogenous mixture of 5-6 different CIDs with a composition dependent on the pharmaceutical formulation. The chemical characteristics of the CIDs indicate that they are formed through a transamidation reaction mainly between the B-chain N-terminal and one of the four amide side-chains of the A chain. GlnA15, AsnA18 and, in particular, AsnA21 participate in the formation of such isopeptide links between two insulin molecules. The covalent insulin-protamine products (CIPP) formed during storage of NPH preparations presumably originate from a similar reaction between the protamine N-terminal with an amide in insulin. Covalent polymerization products, mainly formed during storage of amorphously suspended insulin at higher temperature, were shown to be due to disulfide interactions. Biological in vivo potencies relative to native insulin were less than 2% for the split-(A8-A9)-product and for the covalent disulfide exchange polymers, 4% for the CIPP, approximately 15% for the CIDs, whereas the B3 derivatives exhibited full potency. Rabbit immunization experiments revealed that none of the insulin transformation products had significantly increased immunogenicity in rabbits.

  6. Full system chemical decontamination used in nuclear decommissioning

    International Nuclear Information System (INIS)

    Elder, George; Rottner, Bernard; Braehler, Georg

    2012-01-01

    The decommissioning of nuclear power stations at the end of the operational period of electricity generation offers technical challenges in the safe dismantling of the facility and the minimization of radioactive waste arising from the decommissioning activities. These challenges have been successfully overcome as demonstrated by decommissioning of the first generation of nuclear power plants. One of the techniques used in decommissioning is that of chemical decontamination which has a number of functions and advantages as given here: 1. Removal of contamination from metal surfaces in the reactors cooling systems. 2. Reduction of radioactive exposure to decommissioning workers 3. Minimization of metal waste by decontamination and recycling of metal components 4. Control of contamination when dismantling reactor and waste systems 5. Reduction in costs due to lower radiation fields, lower contamination levels and minimal metal waste volume for disposal. One such chemical decontamination technology was developed for the Electric Power Research Institute (EPRI) by Bradtec (Bradtec is an ONET Technologies subsidiary) and is known as the EPRI DFD system. This paper gives a description of the EPRI DFD system, and highlights the experience using the system. (orig.)

  7. Chemical and physical transformations of organic aerosol from the photo-oxidation of open biomass burning emissions in an environmental chamber

    Directory of Open Access Journals (Sweden)

    C. J. Hennigan

    2011-08-01

    Full Text Available Smog chamber experiments were conducted to investigate the chemical and physical transformations of organic aerosol (OA during photo-oxidation of open biomass burning emissions. The experiments were carried out at the US Forest Service Fire Science Laboratory as part of the third Fire Lab at Missoula Experiment (FLAME III. We investigated emissions from 12 different fuels commonly burned in North American wildfires. The experiments feature atmospheric and plume aerosol and oxidant concentrations; aging times ranged from 3 to 4.5 h. OA production, expressed as a mass enhancement ratio (ratio of OA to primary OA (POA mass, was highly variable. OA mass enhancement ratios ranged from 2.9 in experiments where secondary OA (SOA production nearly tripled the POA concentration to 0.7 in experiments where photo-oxidation resulted in a 30 % loss of the OA mass. The campaign-average OA mass enhancement ratio was 1.7 ± 0.7 (mean ± 1σ; therefore, on average, there was substantial SOA production. In every experiment, the OA was chemically transformed. Even in experiments with net loss of OA mass, the OA became increasingly oxygenated and less volatile with aging, indicating that photo-oxidation transformed the POA emissions. Levoglucosan concentrations were also substantially reduced with photo-oxidation. The transformations of POA were extensive; using levoglucosan as a tracer for POA, unreacted POA only contributed 17 % of the campaign-average OA mass after 3.5 h of exposure to typical atmospheric hydroxyl radical (OH levels. Heterogeneous reactions with OH could account for less than half of this transformation, implying that the coupled gas-particle partitioning and reaction of semi-volatile vapors is an important and potentially dominant mechanism for POA processing. Overall, the results illustrate that biomass burning emissions are subject to extensive chemical processing in the atmosphere, and the timescale for these transformations is rapid.

  8. Proceedings of 26. annual academic conference of China Chemical Society--modern nuclear chemistry and radiochemistry

    International Nuclear Information System (INIS)

    2008-08-01

    26. annual academic conference of China Chemical Society was held in Tianjing, 13-16 July, 2008. This proceedings is about modern nuclear chemistry and radiochemistry, the contents include: new elements and new nuclides; advanced nuclear chemistry; radiochemistry and national security; new radiopharmaceutical chemistry; modern radiological analytical chemistry and large scientific facilities; radiological environmental chemistry and nuclear radioactive waste; actinide chemistry and transactinide chemistry; radiochemistry and cross discipline, etc.

  9. High energy halogen atom reactions activated by nuclear transformations

    International Nuclear Information System (INIS)

    Rack, E.P.

    1990-05-01

    This program, which has been supported for twenty-four years by the Us Atomic Energy Commission and its successor agencies, has produced significant advances in the understanding of the mechanisms of chemical activation by nuclear processes; the stereochemistry of radioactivity for solution of specific problems. This program was contributed to the training of approximately seventy scientists at various levels. This final report includes a review of the areas of research and chronological tabulation of the publications

  10. Upper Secondary French Students, Chemical Transformations and the "Register of Models": A Cross-Sectional Study

    Science.gov (United States)

    Cokelez, Aytekin; Dumon, Alain; Taber, Keith S.

    2008-01-01

    The purpose of this study is to identify how upper secondary school French students (Grade 10-12) interpret chemical transformation with regards to the changes within molecules and atoms, and in terms of intramolecular and/or intermolecular bond breaking. In order to identify and describe the students' assimilated knowledge, four questions were…

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

    International Nuclear Information System (INIS)

    Meshkov, N.A.

    1995-01-01

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

  12. Instrumentation for chemical and radiochemical monitoring in nuclear power plants

    International Nuclear Information System (INIS)

    Nordmann, F.; Ballard, G.

    2009-01-01

    This article details the instrumentation implemented in French nuclear power plants for the monitoring of chemical and radiochemical effluents with the aim of limiting their environmental impact. It describes the controls performed with chemical automata for the search for drifts, anomalies or pollution in a given circuit. The operation principles of the different types of chemical automata are explained as well as the manual controls performed on samples manually collected. Content: 1 - general considerations; 2 - objectives of the chemical monitoring: usefulness of continuous monitoring with automata, transmission to control rooms and related actions, redundancy of automata; 3 - instrumentation and explanations for the main circuits: principle of chemical automata monitoring, instrumentation of the main primary circuit, instrumentation of the main secondary circuit, instrumentation of the tertiary circuit, preparation of water makeup (demineralized water), other loops, instrumentation for effluents and environment monitoring, measurement principles of chemical automata, control and maintenance of chemical automata; 4 - manual controls after sampling; 5 - radiochemical monitoring: automatized radiochemical measurements, manual radiochemical measurements; 6 - conclusion

  13. Transformation of Library Services in Nuclear Malaysia: e-SDI

    International Nuclear Information System (INIS)

    Mohd Hafizal Yusof; Nasaruddin Ahmad; Habibah Adnan

    2015-01-01

    In order to deliver its services to the public, library must have initiatives to attract the public on using their services. One of the services offered by the library is information packaging or Selective Dissemination of Information (SDI). SDI is services that enable the librarian to serve the user on upcoming information according to the users interest. Before this, librarian will package new publication or information regarding certain topics of the user need and deliver it to the target user frequently. Theorically, this service is connection between library and user and back to library again. Nuclear Malaysia Library has used Integrated Library Management Utilities (ILMU) since 2005. Through this system, there is one module known as Article Browsing where its function same with SDI. This paper will elaborate on transformation of SDI services from conventional to the electronic form. (author)

  14. Influence of various parameters on effectiveness of seismic base isolation of nuclear equipment

    International Nuclear Information System (INIS)

    Ebisawa, K.; Kameoka, H.; Takenouchi, I.; Kajiki, S.

    1995-01-01

    Authors developed a methodology and EBISA code for evaluating the applicability and the effectiveness of seismic base isolation of nuclear equipment. In order to investigate the influence of various parameters on the effectiveness of seismic base isolation, a sensitivity analysis was carried out for an emergency transformer with the base isolation devices. It was proved that seismic base isolation of equipment is very effective. This effectiveness can be influenced by the differences of the base isolation devices and the direction of the input seismic wave. (author). 7 refs., 3 figs., 3 tabs

  15. Molten salt fueled nuclear facility with steam-and gas turbine cycles of heat transformation

    International Nuclear Information System (INIS)

    Ananich, P.I.; Bunin, E.N.; Kazazyan, V.T.; Nemtsev, V.A.; Sikorin, S.N.

    2001-01-01

    The molten salt fueled nuclear facilities with fuel circulating in the primary circuit have a series of the potential advantages in comparison with the traditional thermal and fast reactors with solid fuel elements. These advantages are ensured by the possibility to receive effective neutron balance in the core, minimum margin reactivity, more deep fuel burnup, unbroken correctness of the fuel physical and chemical properties and by low prices of the fuel cycle. The neutron and thermal-physical calculations of the various variants of the MSFNF with steam-water and gas turbine power circuits and their technical and economical comparison are carried out in this article. Calculations of molten salt nuclear power plant with gas turbine power circuit have been carried out using chemically reacting working body ''nitrin'' (N304 + 1%NO). The molten salt fueled reactors with the thermal power near of 2300 MW with two fuel compositions have been considered. The base variant has been taken the design of NPP with VVER NP-1000 when comparing the results of the calculations. Its economical performances are presented in prices of 1990. The results of the calculations show that it is difficult to determine the advantages of any one of the variants considered in a unique fashion. But NPP with MSR possesses large reserves in the process of optimization of cycle and energy equipment parameters that can improve its technical and economical performances sufficiently. (author)

  16. Synthesis of iron oxide nanorods via chemical scavenging and phase transformations of intermediates at ambient conditions

    Energy Technology Data Exchange (ETDEWEB)

    Deshmukh, Ruchi; Mehra, Anurag; Thaokar, Rochish, E-mail: rochish@che.iitb.ac.in [Indian Institute of Technology-Bombay, Department of Chemical Engineering (India)

    2017-01-15

    Chemically induced shape transformations of isotropic seeds, comprised of iron oxyhydroxides and iron oxide borate into nanorods, is reported. Transient growth studies show that the nanorods are formed via phase transformation and aggregation of various metastable species. Addition of tetra-methyl-ammonium hydroxide (TMAH) to the in situ synthesized seeds ensures a typical reaction pathway that favors formation of magnetite (Fe {sub 3}O{sub 4}) via the steps of chemical etching, phase transformation of intermediates, and crystal consolidation. Whereas, with addition of sodium hydroxide (NaOH), either magnetite (Fe {sub 3}O{sub 4}) or a mixture of (γ-Fe {sub 2}O{sub 3} + α-FeOOH) is obtained. The shape with both the additives is always that of nanorods. When the seeds treated with TMAH were aged in an ultrasonication bath, rods with almost twice the length and diameter (length = 2800 nm, diameter = 345 nm) are obtained as compared to the sample aged without ultrasonication (length = 1535 nm, diameter = 172 nm). The morphology of nanostructures depending upon other experimental conditions such as, aging the sample at 60 {sup ∘}C, seeds synthesized under ultrasonication/ stirring or externally added are also examined and discussed in detail. All the samples show high coercivity and strong ferromagnetic behavior at room temperature and should be promising candidates as ferro-fluids for various applications.

  17. Development of chemical technology in nuclear fuel cycle

    International Nuclear Information System (INIS)

    Kim, Won Ho; Kim, J. S.; Kim, J. G.

    2004-04-01

    The objectives of this study are to develop the technology for both chemical analysis of fissile materials and fission products and chemical characterization in dry process, and also to compose LA/ICP-MS and micro-XRD systems. Chemical techniques for quantitative analysis of Cs, Tc, Np, Am, Cm in LiCl molten salts and Am, Cm, Tc, 3 H, 14 C in oxidized PWR spent fuel powders were developed for the evaluation of its material balance in the dry process. In particular, the rate of uranium oxide reduction was measured by the determination of concentrations of lithium metal and lithium oxide in LiCl molten salts. The solubility data of the reactants in LiCl molten salt were acquired, the oxide ion selective electrode to determine the oxide contents in the medium being fabricated, and a chronoamperometric technique applicable to in-line and real time monitoring of lithium metal reduction process was developed. On the other side, the electrochemical reduction of uranium oxides was studied, which has contributed to better understand the reduction behavior and thus lead to modify processes involved. Laser ablation ICP-MS system was developed by coupling laser ablation system with ICP-MS system, which was supposed to measure the isotope distribution from core to rim of irradiated fuel. The micro-XRD was developed with a micro beam, two hundreds times as narrow as conventional XRD, to measure structural changes of solid samples by 50μm interval in the radial direction. The performance of the two systems developed was confirmed by means of the examinations on precision, spatial resolution, and reproducibility. The development of LA/ICP-MS and micro-XRD system led to an establishment of techniques for the evaluation of its long-term integrity of high burn-up spent nuclear fuel and these techniques will be applied to the development of new nuclear fuels. Especially, the micro-XRD system will be useful to develop new materials and to control the quality in the various industrial

  18. Nuclear war: short-term chemical and radiative effects of stratospheric injections

    International Nuclear Information System (INIS)

    Luther, F.M.

    1983-10-01

    Earlier investigations of the atmospheric effects of a nuclear war focused primarily on the potential reduction in stratospheric ozone. The numerical models used in those assessments were one-dimensional and calculated the average ozone reduction over the Northern Hemisphere. The results presented here are the first assessment of the potential reduction in total ozone on a subcontinental scale. The purpose is to determine whether regions of large ozone reduction (sometimes called ozone holes) are possible, and to identify the important parameters affecting the magnitude of the ozone reduction and rate of recovery

  19. Nuclear data compression and reconstruction via discrete wavelet transform

    Energy Technology Data Exchange (ETDEWEB)

    Park, Young Ryong; Cho, Nam Zin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-12-31

    Discrete Wavelet Transforms (DWTs) are recent mathematics, and begin to be used in various fields. The wavelet transform can be used to compress the signal and image due to its inherent properties. We applied the wavelet transform compression and reconstruction to the neutron cross section data. Numerical tests illustrate that the signal compression using wavelet is very effective to reduce the data saving spaces. 7 refs., 4 figs., 3 tabs. (Author)

  20. Nuclear data compression and reconstruction via discrete wavelet transform

    Energy Technology Data Exchange (ETDEWEB)

    Park, Young Ryong; Cho, Nam Zin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    Discrete Wavelet Transforms (DWTs) are recent mathematics, and begin to be used in various fields. The wavelet transform can be used to compress the signal and image due to its inherent properties. We applied the wavelet transform compression and reconstruction to the neutron cross section data. Numerical tests illustrate that the signal compression using wavelet is very effective to reduce the data saving spaces. 7 refs., 4 figs., 3 tabs. (Author)

  1. Cocoa Procyanidins Suppress Transformation by Inhibiting Mitogen-activated Protein Kinase Kinase*S⃞

    Science.gov (United States)

    Kang, Nam Joo; Lee, Ki Won; Lee, Dong Eun; Rogozin, Evgeny A.; Bode, Ann M.; Lee, Hyong Joo; Dong, Zigang

    2008-01-01

    Cocoa was shown to inhibit chemically induced carcinogenesis in animals and exert antioxidant activity in humans. However, the molecular mechanisms of the chemopreventive potential of cocoa and its active ingredient(s) remain unknown. Here we report that cocoa procyanidins inhibit neoplastic cell transformation by suppressing the kinase activity of mitogen-activated protein kinase kinase (MEK). A cocoa procyanidin fraction (CPF) and procyanidin B2 at 5 μg/ml and 40 μm, respectively, inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced neoplastic transformation of JB6 P+ mouse epidermal (JB6 P+) cells by 47 and 93%, respectively. The TPA-induced promoter activity and expression of cyclooxygenase-2, which is involved in tumor promotion and inflammation, were dose-dependently inhibited by CPF or procyanidin B2. The activation of activator protein-1 and nuclear factor-κB induced by TPA was also attenuated by CPF or procyanidin B2. The TPA-induced phosphorylation of MEK, extracellular signal-regulated kinase, and p90 ribosomal s6 kinase was suppressed by CPF or procyanidin B2. In vitro and ex vivo kinase assay data demonstrated that CPF or procyanidin B2 inhibited the kinase activity of MEK1 and directly bound with MEK1. CPF or procyanidin B2 suppressed JB6 P+ cell transformation induced by epidermal growth factor or H-Ras, both of which are known to be involved in MEK/ERK signal activation. In contrast, theobromine (up to 80 μm) had no effect on TPA-induced transformation, cyclooxygenase-2 expression, the transactivation of activator protein-1 or nuclear factor-κB, or MEK. Notably, procyanidin B2 exerted stronger inhibitory effects compared with PD098059 (a well known pharmacological inhibitor of MEK) on MEK1 activity and neoplastic cell transformation. PMID:18519570

  2. Determination of air pollutants by nuclear chemical analysis

    International Nuclear Information System (INIS)

    Lesny, J.; Toelgyessy, J.

    1975-01-01

    Nuclear analytical methods are discussed with a view to their applicability in the determination of air pollutants. It is shown that some methods (use of radioactive kryptonates in automatic analyzers, application of activation analysis, X-ray fluorescence methods) are developed in theory and proven in practice in such an extent to be widely used in the near future in the control of the environment. Many other methods are becoming increasingly important for the solution of specific problems of environmental protection (such as the control of sudden environmental contamination in the proximity of chemical plants and industrial centers). (author)

  3. Organization of the lamin scaffold in the internal nuclear matrix of normal and transformed hepatocytes

    International Nuclear Information System (INIS)

    Barboro, Paola; D'Arrigo, Cristina; Repaci, Erica; Patrone, Eligio; Balbi, Cecilia

    2010-01-01

    Nuclear lamins are among the more abundant proteins making up the internal nuclear matrix, but very little is known about their structure in the nucleoplasm. Using immunoelectron microscopy, we demonstrate the organization of lamins in the nuclear matrix isolated from rat hepatocytes for the first time. Lamin epitopes are arrayed both in locally ordered clusters and in quasi-regular rows. Fourier filtering of the images demonstrates that the epitopes are placed at the nodes and halfway between the nodes of square or rhombic lattices that are about 50 nm on each side, as well as along rows at regular ∼25-nm intervals. In addition, we have compared this structure with that of the internal nuclear matrix isolated from persistent hepatocyte nodules. In transformed hepatocytes, the islands of lamin lattice are lost, and only a partial regularity in the rows of gold particles remains. We suggest that orthogonal lattice assembly might be an intrinsic property of lamin molecules, and that the disassembly may be triggered by simple molecular events such as phosphorylation.

  4. Analysis of chemical factors affecting marine ecosystem around nuclear power plant

    International Nuclear Information System (INIS)

    Chun, Kwan Sik; Choi, Yoon Dong; Chun, Ki Jeong; Kim, Jin Kyu; Jung, Kyeong Chai; Lee, Yeong Keun; Park, Hyo Kook

    1994-06-01

    The ecological data of the coastal area of Youngkwang nuclear power plant from 1987 to 1993 were comprehensively analyzed, and various physical and chemical properties of sea water and sediments were measured. Major factors affecting phytoplankton standing crops were suspended substances, nitrate, and silicate. The contents of iron, chromium, copper, and sulfur in sediments sampled from the discharge channel were slightly higher than those in the other areas. In order to qantify the chemical impacts on marine ecosystem, it is desirable that a systematic survey be made through the whole year cycle to assure the consistency and confidence of the related data. (Author)

  5. Chemical transformations associated with neutronic irradiation of telluric acid

    International Nuclear Information System (INIS)

    Bertet, M.

    1963-01-01

    The chemical transformations which arise from irradiation of telluric acid with neutrons have been studied under several experimental conditions. The effects of the reaction (n, γ ) on Te VI and of the isomeric transitions 131m Te VI → 131 Te and 129m Te VI → 129 Te, and the oxidation states of 131 I formed by β decay of 131 Te have been investigated in detail. The Szilard-Chalmers effect has been put in evidence. Retention (R) depends on the isomeric state of Rd-Te and is higher for the metastable isotopes. R increases with the time of irradiation. R seems to be independent of the medium which is used for dissolving telluric acid irradiated in the solid state. Higher values of R are found if the acid is irradiated in neutral or alkaline solution; irradiation in acid solution leads to lower values for R. Retention for 131 Te VI and 129 Te VI formed by isomeric transition depends on the pH of the solution where this disintegration occurs. For instance, with 129 Te, R is greater in 6 M NaOH (80 per cent) than in 3 M HCI (40 per cent). The relative amounts of the oxidation states of 131 I (reduced fraction (I - , IO - , I 2 ), iodate and periodate) depend on the medium, both if the acid is irradiated in the solid state and it is irradiated in solution. In the first case, the reduced fraction increases from 12 to 89 per cent when the dissolving medium is changed from neutral to 0.8 M HNO 3 . In the second case, the reduced fraction is 90 per cent in neutral or acid solution and 64 per cent in 0.5 M KOH. It has been shown, furthermore, that microamounts of Te VI are formed in certain cases. (author) [fr

  6. Research on the chemical speciation of actinides

    International Nuclear Information System (INIS)

    Jung, Euo Chang; Park, K. K.; Cho, H. R.

    2012-04-01

    A demand for the safe and effective management of spent nuclear fuel and radioactive waste generated from nuclear power plant draws increasing attention with the growth of nuclear power industry. The objective of this project is to establish the basis of research on the actinide chemistry by using highly sensitive and advanced laser-based spectroscopic systems. Researches on the chemical speciation of actinides are prerequisite for the development of technologies related to nuclear fuel cycles, especially, such as the safe management of high level radioactive wastes and the chemical examination of irradiated nuclear fuels. For supporting these technologies, laser-based spectroscopies have been applied for the chemical speciation of actinide in aqueous solutions and the quantitative analysis of actinide isotopes in spent nuclear fuels. In this report, results on the following subjects have been summarized. Development of TRLFS technology for the chemical speciation of actinides, Development of laser-induced photo-acoustic spectroscopy (LPAS) system, Application of LIBD technology to investigate dynamic behaviors of actinides dissolution reactions, Development of nanoparticle analysis technology in groundwater using LIBD, Chemical speciation of plutonium complexes by using a LWCC system, Development of LIBS technology for the quantitative analysis of actinides, Evaluation on the chemical reactions between actinides and humic substances, Spectroscopic speciation of uranium-ligand complexes in aqueous solution, Chemical speciation of actinides adsorbed on metal oxides surfaces

  7. Effects of protease inhibitors on radiation transformation in vitro

    International Nuclear Information System (INIS)

    Kennedy, A.R.; Little, J.B.

    1981-01-01

    We have investigated the effects of three protease inhibitors, antipain, leupeptin, and soybean trypsin inhibitor, on the induction of oncogenic transformation in mouse C3H10T 1/2 cells by X-rays. The patterns of inhibition by the three protease inhibitors were different. Antipain was the most effective, having the ability to suppress completely radiation transformation as well as radiation transformation enhanced by the phorbol ester promoting agent 12-O-tetradecanoylphorbol-13-acetate. The fact that antipain could suppress transformation when present for only 1 day following irradiation suggests that an effect on a DNA repair process might be important in its action. Leupeptin was less effective than antipain in its inhibition of radiation transformation. Soybean trypsin inhibitor suppressed only the promotional effects of 12-O-tetradecanoylphorbol-13-acetate on transformation. Our results suggest that there may be more than one protease involved in carcinogenesis

  8. Disposal and handling of nuclear steam generator chemical cleaning wastes

    International Nuclear Information System (INIS)

    Larrick, A.P.; Schneidmiller, D.

    1978-01-01

    A large number of pressurized water nuclear reactor electrical generating plants have experienced a corrosion-related problem with their steam generators known as denting. Denting is a mechanical deformation of the steam generator tubes that occurs at the tube support plates. Corrosion of the tube support plates occurs within the annuli through which the tubes pass and the resulting corrosion oxides, which are larger in volume than the original metal, compress and deform the tubes. In some cases, the induced stresses have been severe enough to cause tube and/or support cracking. The problem was so severe at the Turkey Point and Surrey plants that the tubing is being replaced. For less severe cases, chemical cleaning of the oxides, and other materials which deposit in the annuli from the water, is being considered. A Department of Energy-sponsored program was conducted by Consolidated Edison Co. of New York which identified several suitable cleaning solvents and led to in-plant chemical cleaning pilot demonstrations in the Indian Point Unit 1 steam generators. Current programs to improve the technology are being conducted by the Electric Power Research Institute, and the three PWR NSSS vendors with the assistance of numerous consultants, vendors, and laboratories. These programs are expected to result in more effective, less corrosive solvents. However, after a chemical cleaning is conducted, a large problem still remains- that of disposing of the spent wastes. The paper summarizes some of the methods currently available for handling and disposal of the wastes

  9. Leader Development in Nuclear, Biological, and Chemical Defense: Trained and Ready

    National Research Council Canada - National Science Library

    Van

    2001-01-01

    .... Careful and deliberate preparation and emphasis on leader development now will obviate the devastating role of WMD in the future and ensure that the Army is nuclear, biological, and chemical (NBC) trained and ready...

  10. The structural evolution and diffusion during the chemical transformation from cobalt to cobalt phosphide nanoparticles

    KAUST Repository

    Ha, Don-Hyung

    2011-01-01

    We report the structural evolution and the diffusion processes which occur during the phase transformation of nanoparticles (NPs), ε-Co to Co 2P to CoP, from a reaction with tri-n-octylphosphine (TOP). Extended X-ray absorption fine structure (EXAFS) investigations were used to elucidate the changes in the local structure of cobalt atoms which occur as the chemical transformation progresses. The lack of long-range order, spread in interatomic distances, and overall increase in mean-square disorder compared with bulk structure reveal the decrease in the NP\\'s structural order compared with bulk structure, which contributes to their deviation from bulk-like behavior. Results from EXAFS show both the Co2P and CoP phases contain excess Co. Results from EXAFS, transmission electron microscopy, X-ray diffraction, and density functional theory calculations reveal that the inward diffusion of phosphorus is more favorable at the beginning of the transformation from ε-Co to Co2P by forming an amorphous Co-P shell, while retaining a crystalline cobalt core. When the major phase of the sample turns to Co 2P, the diffusion processes reverse and cobalt atom out-diffusion is favored, leaving a hollow void, characteristic of the nanoscale Kirkendall effect. For the transformation from Co2P to CoP theory predicts an outward diffusion of cobalt while the anion lattice remains intact. In real samples, however, the Co-rich nanoparticles continue Kirkendall hollowing. Knowledge about the transformation method and structural properties provides a means to tailor the synthesis and composition of the NPs to facilitate their use in applications. © 2011 The Royal Society of Chemistry.

  11. Chemical modeling of irreversible reactions in nuclear waste-water-rock systems

    International Nuclear Information System (INIS)

    Wolery, T.J.

    1981-02-01

    Chemical models of aqueous geochemical systems are usually built on the concept of thermodynamic equilibrium. Though many elementary reactions in a geochemical system may be close to equilibrium, others may not be. Chemical models of aqueous fluids should take into account that many aqueous redox reactions are among the latter. The behavior of redox reactions may critically affect migration of certain radionuclides, especially the actinides. In addition, the progress of reaction in geochemical systems requires thermodynamic driving forces associated with elementary reactions not at equilibrium, which are termed irreversible reactions. Both static chemical models of fluids and dynamic models of reacting systems have been applied to a wide spectrum of problems in water-rock interactions. Potential applications in nuclear waste disposal range from problems in geochemical aspects of site evaluation to those of waste-water-rock interactions. However, much further work in the laboratory and the field will be required to develop and verify such applications of chemical modeling

  12. The UK chemical nuclear data library: a summary of the data available in ENDF/B format

    International Nuclear Information System (INIS)

    Davies, B.S.J.

    1981-11-01

    The UK Chemical Nuclear Data Committee files have been considerably revised and extended. The files now embrace: fission yields (C31), fission product decay data (UKFPDD-2), activation product decay data (UKPADD-1), and heavy element decay data (UKHEDD-1). The fission yield data is based on Crouch's third round of adjustment and includes yields to isometric states. The decay data files include data on half-life, decay modes, branching ratios and alpha, beta and gamma radiation energies and intensities. The data have all been recommended by the UK Chemical Nuclear Data Committee for use in the UK reactor programme; they are stored on magnetic tape at AERE Harwell, AEE Winfrith and CEGB Berkeley Nuclear Laboratories. (author)

  13. Nuclear transmutations

    International Nuclear Information System (INIS)

    Mikulaj, V.

    1992-01-01

    Two types of nuclear transmutations are outlined, namely the radioactive transmutations and nuclear reactions. The basic characteristics are given of radioactive transmutations (gamma transmutations and isomeric transitions, beta, alpha transmutations, spontaneous fission and spontaneous emission of nucleons), their kinetics and the influence of the physical and chemical state of the radionuclide on the transmutation rate. The basic characteristics are described of nuclear reactions (reactions of neutrons including fission, reactions induced by charged particles and photons), their kinetics, effective cross sections and their mechanism. Chemical reactions caused by nuclear transmutations are discussed (recoil energy, properties of hot atoms, Szilard-Chalmers effect). A brief information is given on the behavior of radionuclides in trace concentrations. (Z.S.) 2 tabs., 19 figs., 12 refs

  14. Nuclear compression effects on pion production in nuclear collisions

    International Nuclear Information System (INIS)

    Sano, M.; Gyulassy, M.; Wakai, M.; Kitazoe, Y.

    1985-01-01

    We show that the method of analyzing the pion excitation function proposed by Stock et al. may determine only a part of the nuclear matter equation of state. With the addition of missing kinetic energy terms the implied high density nuclear equation of state would be much stiffer than expected from conventional theory. A stiff equation of state would also follow if shock dynamics with early chemical freeze out were valid. (orig.)

  15. Gene-Transformation-Induced Changes in Chemical Functional Group Features and Molecular Structure Conformation in Alfalfa Plants Co-Expressing Lc-bHLH and C1-MYB Transcriptive Flavanoid Regulatory Genes: Effects of Single-Gene and Two-Gene Insertion.

    Science.gov (United States)

    Heendeniya, Ravindra G; Yu, Peiqiang

    2017-03-20

    Alfalfa ( Medicago sativa L.) genotypes transformed with Lc-bHLH and Lc transcription genes were developed with the intention of stimulating proanthocyanidin synthesis in the aerial parts of the plant. To our knowledge, there are no studies on the effect of single-gene and two-gene transformation on chemical functional groups and molecular structure changes in these plants. The objective of this study was to use advanced molecular spectroscopy with multivariate chemometrics to determine chemical functional group intensity and molecular structure changes in alfalfa plants when co-expressing Lc-bHLH and C1-MYB transcriptive flavanoid regulatory genes in comparison with non-transgenic (NT) and AC Grazeland (ACGL) genotypes. The results showed that compared to NT genotype, the presence of double genes ( Lc and C1 ) increased ratios of both the area and peak height of protein structural Amide I/II and the height ratio of α-helix to β-sheet. In carbohydrate-related spectral analysis, the double gene-transformed alfalfa genotypes exhibited lower peak heights at 1370, 1240, 1153, and 1020 cm -1 compared to the NT genotype. Furthermore, the effect of double gene transformation on carbohydrate molecular structure was clearly revealed in the principal component analysis of the spectra. In conclusion, single or double transformation of Lc and C1 genes resulted in changing functional groups and molecular structure related to proteins and carbohydrates compared to the NT alfalfa genotype. The current study provided molecular structural information on the transgenic alfalfa plants and provided an insight into the impact of transgenes on protein and carbohydrate properties and their molecular structure's changes.

  16. Shielding behavior of multi-transformation phase change materials (MTPCM) against nuclear radiations

    International Nuclear Information System (INIS)

    Kumar, Ravindra; Goplani, Deepak; Kumar, Rohitash; Das, Mrinal Kumar; Kumar, Pramod; Jodha, Ajay Singh; Misra, Manoj; Khatri, P.K.

    2008-01-01

    In nuclear hardened structures and AFV's, special shielding materials are being used to provide protection from radiations generated in nuclear blast. However, in blast an intense heat pulse is also generated along with radiation. Currently used shield does not take care of this heat pulse. Defence Laboratory, Jodhpur has developed multi transformation phase change materials (MTPCM) based cool panels for passive moderation of temperature in severe desert heat. The MTPCM contains light nuclei of hydrogen, carbon and oxygen, and thus can absorb good amount of neutrons. MTPCM can also absorb intense heat pulse along with heat generated by secondary fires during blast as its latent heat (160-170 J/g) without significant rise in temperature (melting point 36-38 deg. C). Thus MTPCM can provide protection against both radiation as well as heat pulse generated in a nuclear blast along with its designed regular function of passively moderating temperature below 40 deg C during severe desert summer. A study has been undertaken to explore multiple applications of MTPCM panel. Protection factor provided by standard MTPCM panels against neutron and gamma radiations (both initial and fall out) were measured and results compared with PF provided by special lining pad currently being used in AFV's and field structures for nuclear protection. It is observed that MTPCM provides good PF (2.17) against neutron which is better than currently used shield pads (PFP%1.8). Present paper discusses results of this study. (author)

  17. Chemical ageing and transformation of diffusivity in semi-solid multi-component organic aerosol particles

    Science.gov (United States)

    Pfrang, C.; Shiraiwa, M.; Pöschl, U.

    2011-07-01

    Recent experimental evidence underlines the importance of reduced diffusivity in amorphous semi-solid or glassy atmospheric aerosols. This paper investigates the impact of diffusivity on the ageing of multi-component reactive organic particles approximating atmospheric cooking aerosols. We apply and extend the recently developed KM-SUB model in a study of a 12-component mixture containing oleic and palmitoleic acids. We demonstrate that changes in the diffusivity may explain the evolution of chemical loss rates in ageing semi-solid particles, and we resolve surface and bulk processes under transient reaction conditions considering diffusivities altered by oligomerisation. This new model treatment allows prediction of the ageing of mixed organic multi-component aerosols over atmospherically relevant timescales and conditions. We illustrate the impact of changing diffusivity on the chemical half-life of reactive components in semi-solid particles, and we demonstrate how solidification and crust formation at the particle surface can affect the chemical transformation of organic aerosols.

  18. Chemical ageing and transformation of diffusivity in semi-solid multi-component organic aerosol particles

    Directory of Open Access Journals (Sweden)

    C. Pfrang

    2011-07-01

    Full Text Available Recent experimental evidence underlines the importance of reduced diffusivity in amorphous semi-solid or glassy atmospheric aerosols. This paper investigates the impact of diffusivity on the ageing of multi-component reactive organic particles approximating atmospheric cooking aerosols. We apply and extend the recently developed KM-SUB model in a study of a 12-component mixture containing oleic and palmitoleic acids. We demonstrate that changes in the diffusivity may explain the evolution of chemical loss rates in ageing semi-solid particles, and we resolve surface and bulk processes under transient reaction conditions considering diffusivities altered by oligomerisation. This new model treatment allows prediction of the ageing of mixed organic multi-component aerosols over atmospherically relevant timescales and conditions. We illustrate the impact of changing diffusivity on the chemical half-life of reactive components in semi-solid particles, and we demonstrate how solidification and crust formation at the particle surface can affect the chemical transformation of organic aerosols.

  19. Investigating the role for adaptation of the microbial community to transform trace organic chemicals during managed aquifer recharge

    KAUST Repository

    Alidina, Mazahirali; Li, Dong; Drewes, Jorg

    2014-01-01

    This study was undertaken to investigate whether adaptation by pre-exposure to trace organic chemicals (TOrCs) was necessary for microbial transformation during managed aquifer recharge (MAR). Two pairs of laboratory-scale soil columns, each

  20. Employment of neural networks for analysis of chemical composition and cooling rate effect on CCT diagrams shape

    International Nuclear Information System (INIS)

    Dobrzanski, L.A.; Trzaska, J.

    2004-01-01

    The paper presents possibility of employment of the original supercooled austenite transformation anisothermic diagrams forecasting method for analysis of the chemical composition effect on the CCT diagrams shape. The developed model makes it possible to substitute computer simulation for the costly and time consuming experiments. The information derived from calculations make it possible to plot diagrams illustrating the effects of the particular elements or pairs of elements, as well as cooling rate and/or austenitizing temperature, on any temperature or time describing transformations in steel during its continuous cooling. Evaluation is also possible of the effect of the aforementioned factors on hardness and fractions of the particular structural constituents. (author)

  1. Hydrodeoxygenation processes: advances on catalytic transformations of biomass-derived platform chemicals into hydrocarbon fuels.

    Science.gov (United States)

    De, Sudipta; Saha, Basudeb; Luque, Rafael

    2015-02-01

    Lignocellulosic biomass provides an attractive source of renewable carbon that can be sustainably converted into chemicals and fuels. Hydrodeoxygenation (HDO) processes have recently received considerable attention to upgrade biomass-derived feedstocks into liquid transportation fuels. The selection and design of HDO catalysts plays an important role to determine the success of the process. This review has been aimed to emphasize recent developments on HDO catalysts in effective transformations of biomass-derived platform molecules into hydrocarbon fuels with reduced oxygen content and improved H/C ratios. Liquid hydrocarbon fuels can be obtained by combining oxygen removal processes (e.g. dehydration, hydrogenation, hydrogenolysis, decarbonylation etc.) as well as by increasing the molecular weight via C-C coupling reactions (e.g. aldol condensation, ketonization, oligomerization, hydroxyalkylation etc.). Fundamentals and mechanistic aspects of the use of HDO catalysts in deoxygenation reactions will also be discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Climate and chemistry effects of a regional scale nuclear conflict

    OpenAIRE

    Stenke A.; Hoyle C. R.; Luo B.; Rozanov E.; Groebner J.; Maag L.; Broennimann S.; Peter T.

    2013-01-01

    Previous studies have highlighted the severity of detrimental effects for life on Earth after an assumed regionally limited nuclear war. These effects are caused by climatic, chemical and radiative changes persisting for up to one decade. However, so far only a very limited number of climate model simulations have been performed, giving rise to the question how realistic previous computations have been. This study uses the coupled chemistry climate model (CCM) SOCOL, which belongs to a...

  3. Technique for calculating radioactivity penetration into soil through a break in the lower part of the containment shell during a nuclear power plant accident

    International Nuclear Information System (INIS)

    Basanskii, E.G.; Bondarenko, A.G.; Gavrilov, A.L.; Kudryashov, N.A.; Kul'zhik, M.N.; Pokrovskii, S.M.

    1992-01-01

    Accurate prediction of the development of processes which accompany severe accidents at nuclear power plants requires models of specific physical-chemical processes and the entire set of physical-chemical transformations. Developed here are two-dimensional methods for calculating the penetration of radionuclides into the soil through a break which arises in a buried part of the containment shell or the concrete foundation plate due to interactions with the melted core as a result of its complete destruction. The method discussed here for reducing the transport of radionuclides by a steam-gas mixture to a system of ordinary differential equations allows well-developed algorithms to be used effectively for calculating kinetics and radioactive decay-chain transformations in the examined problems. 10 refs., 3 figs

  4. CO_2 valorization - Part. 2: chemical transformation ways

    International Nuclear Information System (INIS)

    Dumergues, Laurent

    2016-01-01

    Carbon dioxide (CO_2) can be used in many ways as a raw material or chemical reagent. The chemical conversion of CO_2 used as a feedstock is achievable by different techniques: mineralization, organic synthesis, hydrogenation, dry reforming, electrolysis, thermolysis, etc. The products obtained have applications as energy products, chemicals, building materials, etc. Choosing an appropriate CO_2 reuse technology will depend on technical and economic requirements (such as the CO_2 purity needed, technological maturity, cost-effectiveness, etc.) and also environmental and social criteria

  5. Chemical mining of primary copper ores by use of nuclear technology

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, A E [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-15

    Chemical mining of primary copper ores, with nuclear explosives to break the ore and in-situ hydrostatic pressure to accelerate dissolution of primary ore minerals, may be feasible. A contained nuclear explosion well below the water table would be used to provide a mass of broken ore in a flooded 'chimney'. The hydrostatic pressure in the chimney should increase the solubility of oxygen in a water-sulfuric acid system enough to allow primary copper minerals such as chalcopyrite and bornite to be dissolved in an acceptably short time. Circulation and collection would be accomplished through drill holes. This method should be especially applicable to the deep portions of porphyry copper deposits that are not economical to mine by present techniques. (author)

  6. Comparative Studies of Chemical Effects following Nuclear Reactions and Transformations on Metal Organic Phenyl Compounds; Etudes Comparatives des Effets Chimiques Induits par les Reactions et les Transformations Nucleaires sur des Composes Phenylmetalliques; 0421 0420 0410 0414 ; Estudios Comparativos de los Efectos Quimicos de las Reacciones y Transformaciones Nucleares en Compuestos Fenil-Organometalicos

    Energy Technology Data Exchange (ETDEWEB)

    Merz, E.; Riedel, H. J. [Kernforschungsanlage, Juelich, Federal Republic of Germany (Germany)

    1965-04-15

    A study of the chemical effects created by the energetic recoil atoms of nuclear reactions in solids and liquids was made on the basis of a broad comparison of the products formed by (n, {gamma}) and (n, 2n) processes in the metalphenyl compounds of germanium, tin, lead, arsenic and antimony. In addition, the radioactive recoil products formed after the K-capture process on Ge{sup 68} - tetraphenyl are compared with the results from the (n, {gamma}) -process on Ga-triphenyl and the (n,p) process on Ge-tetra phenyl. Finally, the studies include the {beta}{sup -} transition on Ge{sup 77}-tetraphenyl to As{sup 77}. Applying different separation methods, e.g. adsorption chromatography on alumina, ion exchange and electrophoresis, the various radioactive recoil products were separated and the individual yields determined. It was found that in nuclear reactions the compounds of the mentioned metals having identical ligands formed practically the same classes of recoil products. The yield distribution however reveals characteristic alterations between the (n, {gamma}) and (n, 2n) reaction. Only a small influence on the yields is perceptible when irradiations are performed in liquids and solutions. The large differences found for the new compounds formed by nuclear transformations are striking, not only in the kind of typical products but also in their percentage yields. Thus, several recoil products of Ge and Ga with metalorganic character were found by nuclear reactions on Ge-tetraphenyl that could not be detected at all by the K-capture process on Ge{sup 68}-tetraphenyl. The {beta}{sup -} decay on Ge{sup 77}-tetraphenyl produces practically the same chemical compounds as were observed by nuclear reactions. However, a remarkable increase in the portion of the labelled parent molecules (retention) is typical for the {beta}{sup -} transition. The results are discussed on the basis of theoretical considerations of the amount of kinetic energy transferred to the reacting

  7. Agrobacterium tumefaciens-mediated transformation of oleaginous yeast Lipomyces species.

    Science.gov (United States)

    Dai, Ziyu; Deng, Shuang; Culley, David E; Bruno, Kenneth S; Magnuson, Jon K

    2017-08-01

    Interest in using renewable sources of carbon, especially lignocellulosic biomass, for the production of hydrocarbon fuels and chemicals has fueled interest in exploring various organisms capable of producing hydrocarbon biofuels and chemicals or their precursors. The oleaginous (oil-producing) yeast Lipomyces starkeyi is the subject of active research regarding the production of triacylglycerides as hydrocarbon fuel precursors using a variety of carbohydrate and nutrient sources. The genome of L. starkeyi has been published, which opens the door to production strain improvements through the development and use of the tools of synthetic biology for this oleaginous species. The first step in establishment of synthetic biology tools for an organism is the development of effective and reliable transformation methods with suitable selectable marker genes and demonstration of the utility of the genetic elements needed for expression of introduced genes or deletion of endogenous genes. Chemical-based methods of transformation have been published but suffer from low efficiency. To address these problems, Agrobacterium-mediated transformation was investigated as an alternative method for L. starkeyi and other Lipomyces species. In this study, Agrobacterium-mediated transformation was demonstrated to be effective in the transformation of both L. starkeyi and other Lipomyces species. The deletion of the peroxisomal biogenesis factor 10 gene was also demonstrated in L. starkeyi. In addition to the bacterial antibiotic selection marker gene hygromycin B phosphotransferase, the bacterial β-glucuronidase reporter gene under the control of L. starkeyi translation elongation factor 1α promoter was also stably expressed in six different Lipomyces species. The results from this study demonstrate that Agrobacterium-mediated transformation is a reliable and effective genetic tool for homologous recombination and expression of heterologous genes in L. starkeyi and other Lipomyces

  8. Preface: Special Topic on Nuclear Quantum Effects.

    Science.gov (United States)

    Tuckerman, Mark; Ceperley, David

    2018-03-14

    Although the observable universe strictly obeys the laws of quantum mechanics, in many instances, a classical description that either ignores quantum effects entirely or accounts for them at a very crude level is sufficient to describe a wide variety of phenomena. However, when this approximation breaks down, as is often the case for processes involving light nuclei, a full quantum treatment becomes indispensable. This Special Topic in The Journal of Chemical Physics showcases recent advances in our understanding of nuclear quantum effects in condensed phases as well as novel algorithmic developments and applications that have enhanced the capability to study these effects.

  9. Preface: Special Topic on Nuclear Quantum Effects

    Science.gov (United States)

    Tuckerman, Mark; Ceperley, David

    2018-03-01

    Although the observable universe strictly obeys the laws of quantum mechanics, in many instances, a classical description that either ignores quantum effects entirely or accounts for them at a very crude level is sufficient to describe a wide variety of phenomena. However, when this approximation breaks down, as is often the case for processes involving light nuclei, a full quantum treatment becomes indispensable. This Special Topic in The Journal of Chemical Physics showcases recent advances in our understanding of nuclear quantum effects in condensed phases as well as novel algorithmic developments and applications that have enhanced the capability to study these effects.

  10. Escalation of terrorism? On the risk of attacks with chemical, biological, radiological and nuclear weapons or materials; Eskalation des Terrors? Ueber das Anschlagsrisiko mit chemischen, biologischen, radiologischen und nuklearen Waffen oder Stoffen

    Energy Technology Data Exchange (ETDEWEB)

    Nass, Jens

    2010-07-01

    The report on the risk of attacks with chemical, biological, radiological and nuclear weapons or materials covers the following topics: the variety of terrorism: ethnic-nationalistic, politically motivated, social revolutionary, political extremism, religious fanaticism, governmental terrorism; CBRN (chemical, biological, radiological, nuclear) weapons and materials: their availability and effectiveness in case of use; potential actor groups; prevention and counter measures, emergency and mitigating measures.

  11. The thermo field transformation in the quasiparticle-phonon nuclear model

    International Nuclear Information System (INIS)

    Vdovin, A.I.; Kosov, D.S.

    1993-01-01

    The method of extension of quasiparticle-phonon nuclear model to describe hot nuclei is proposed. For this aim the formalism of the thermo field dynamics is used. Following the main principles of the TFD we express the Hamiltonian of the QPM in terms of thermal quasiparticles. The coefficients of the corresponding transformation are determined by minimizing the grand thermodynamical potential of a hot nucleus in the thermal vacuum state. Then the RPA part of the thermal QPM Hamiltonian is extracted and the RPA equations are derived. They are in the agreement with the RPA equations derived by the Green function method and the equation of motion method. (author.). 15 refs

  12. Substitution effect in nuclear magnetic resonance of C-13: α methoxicyclohexanones

    International Nuclear Information System (INIS)

    Lopez Holland, M.A.G.

    1984-01-01

    Eletronic and steric interactions between the carbonyl and methoxyl groups in α-methoxicyclohexanones by H-1 and C-13 nuclear magnetic resonance spectroscopy (n.m.r) is studied. Interpretation of H-1 n.m.r measurements based on the carbonyl group anisotropy is made. The asigment of spectral lines to specific nuclear by Lanthanide Shift Reagent Experiments is confirmed. Interpretation of C-13 n.m.r. spectra with respect to molecular effects and emphirical relationships associated with the substituent was analysed. The C-13 chemical shift asignment by comparison with results of partially (SFORD) and fully decompled spectra and also by relating the measured chemical shift with values cited in the literature for similar compounds are made. A qualitative study using I.R. spectroscopy in attempt to evaluate the predominance of one the conformers of the studied compounds in solutions of n-hexan and chloroform is made. (M.J.C.) [pt

  13. Postsynthesis Transformation of Insulating Cs4PbBr6 Nanocrystals into Bright Perovskite CsPbBr3 through Physical and Chemical Extraction of CsBr.

    Science.gov (United States)

    Palazon, Francisco; Urso, Carmine; De Trizio, Luca; Akkerman, Quinten; Marras, Sergio; Locardi, Federico; Nelli, Ilaria; Ferretti, Maurizio; Prato, Mirko; Manna, Liberato

    2017-10-13

    Perovskite-related Cs 4 PbBr 6 nanocrystals present a "zero-dimensional" crystalline structure where adjacent [PbBr 6 ] 4- octahedra do not share any corners. We show in this work that these nanocrystals can be converted into "three-dimensional" CsPbBr 3 perovskites by extraction of CsBr. This conversion drastically changes the optoelectronic properties of the nanocrystals that become highly photoluminescent. The extraction of CsBr can be achieved either by thermal annealing (physical approach) or by chemical reaction with Prussian Blue (chemical approach). The former approach can be simply carried out on a dried film without addition of any chemicals but does not yield a full transformation. Instead, reaction with Prussian Blue in solution achieves a full transformation into the perovskite phase. This transformation was also verified on the iodide counterpart (Cs 4 PbI 6 ).

  14. Geochemical induced degradation of environmental chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Parlar, H

    1984-09-01

    Attempts to correlate the concentration of organic chemicals in the environment with their production figures have resulted in a large deficit; this includes environmental chemicals such as chlorinated hydrocarbons. It has been assumed that analytical errors accounted for this deficit. Another explanation, however, allows for reactions of compounds under biotic and abiotic conditions. Because of the biostability of many organic chemicals biological transformation mechanisms can bring about slight change only. By contrast, abiotic environmental factors such as the UV-irradiation or decomposition on natural surfaces contribute considerably to the transformation of this substance class. An investigation of such abiotic charges of organic chemicals must therefore pay particular attention to dynamic and catalytic effects primarily attributable to the respective molecular state and interactions with the environment. This paper deals with the photoinduced reactions of organic substances adsorbed on natural surfaces and their significance for the degradability of environmental chemicals.

  15. Relativistic heavy-atom effects on heavy-atom nuclear shieldings

    Science.gov (United States)

    Lantto, Perttu; Romero, Rodolfo H.; Gómez, Sergio S.; Aucar, Gustavo A.; Vaara, Juha

    2006-11-01

    The principal relativistic heavy-atom effects on the nuclear magnetic resonance (NMR) shielding tensor of the heavy atom itself (HAHA effects) are calculated using ab initio methods at the level of the Breit-Pauli Hamiltonian. This is the first systematic study of the main HAHA effects on nuclear shielding and chemical shift by perturbational relativistic approach. The dependence of the HAHA effects on the chemical environment of the heavy atom is investigated for the closed-shell X2+, X4+, XH2, and XH3- (X =Si-Pb) as well as X3+, XH3, and XF3 (X =P-Bi) systems. Fully relativistic Dirac-Hartree-Fock calculations are carried out for comparison. It is necessary in the Breit-Pauli approach to include the second-order magnetic-field-dependent spin-orbit (SO) shielding contribution as it is the larger SO term in XH3-, XH3, and XF3, and is equally large in XH2 as the conventional, third-order field-independent spin-orbit contribution. Considering the chemical shift, the third-order SO mechanism contributes two-thirds of the difference of ˜1500ppm between BiH3 and BiF3. The second-order SO mechanism and the numerically largest relativistic effect, which arises from the cross-term contribution of the Fermi contact hyperfine interaction and the relativistically modified spin-Zeeman interaction (FC/SZ-KE), are isotropic and practically independent of electron correlation effects as well as the chemical environment of the heavy atom. The third-order SO terms depend on these factors and contribute both to heavy-atom shielding anisotropy and NMR chemical shifts. While a qualitative picture of heavy-atom chemical shifts is already obtained at the nonrelativistic level of theory, reliable shifts may be expected after including the third-order SO contributions only, especially when calculations are carried out at correlated level. The FC/SZ-KE contribution to shielding is almost completely produced in the s orbitals of the heavy atom, with values diminishing with the principal

  16. Application of in vitro cell transformation assays in regulatory toxicology for pharmaceuticals, chemicals, food products and cosmetics.

    Science.gov (United States)

    Vanparys, Philippe; Corvi, Raffaella; Aardema, Marilyn J; Gribaldo, Laura; Hayashi, Makoto; Hoffmann, Sebastian; Schechtman, Leonard

    2012-04-11

    Two year rodent bioassays play a key role in the assessment of carcinogenic potential of chemicals to humans. The seventh amendment to the European Cosmetics Directive will ban in 2013 the marketing of cosmetic and personal care products that contain ingredients that have been tested in animal models. Thus 2-year rodent bioassays will not be available for cosmetics/personal care products. Furthermore, for large testing programs like REACH, in vivo carcinogenicity testing is impractical. Alternative ways to carcinogenicity assessment are urgently required. In terms of standardization and validation, the most advanced in vitro tests for carcinogenicity are the cell transformation assays (CTAs). Although CTAs do not mimic the whole carcinogenesis process in vivo, they represent a valuable support in identifying transforming potential of chemicals. CTAs have been shown to detect genotoxic as well as non-genotoxic carcinogens and are helpful in the determination of thresholds for genotoxic and non-genotoxic carcinogens. The extensive review on CTAs by the OECD (OECD (2007) Environmental Health and Safety Publications, Series on Testing and Assessment, No. 31) and the proven within- and between-laboratories reproducibility of the SHE CTAs justifies broader use of these methods to assess carcinogenic potential of chemicals. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Formation, transformation and dissolution of phases formed on surfaces

    International Nuclear Information System (INIS)

    Shoesmith, D.W.

    1983-03-01

    The basic mechanisms of film growth, transformation, and dissolution of phases formed on surfaces are discussed. Film growth can occur via solid-state processes or via substrate (usally metal or alloy) dissolution, followed by local supersaturation and precipitation of an insoluble phase. The phase(s) formed may be metastable and transform to a more stable phase, via either solid-state or dissolution-reprecipitation processes. Film dissolution reactions can also occur via a variety of mechanisms, including: (i) direct chemical dissolution when no oxidation state change occurs; (ii) redox dissolution when the film dissolves via a redox reaction involving a reducing or oxidizing agent in solution; and (iii) autoreduction, where film dissolution is coupled to metal dissolution. Such film-growth and dissolution processes, which often produce complex multilayer films, are common in the nuclear industry. A number of examples are discussed

  18. Composition effects on chemical durability and viscosity of nuclear waste glasses - systematic studies and structural thermodynamic models

    International Nuclear Information System (INIS)

    Feng, X.

    1988-01-01

    Two of the primary criteria for the acceptability of nuclear waste glasses are their durability, i.e. chemical resistance to aqueous attack for 10 4 to 10 5 years, and processability, which requires their viscosity at the desired melt temperature to be sufficiently low. Chapter 3 presents the results of systematic composition variation studies around the preliminary reference glass composition WV205 and an atomistic interpretation of the effects of individual oxides. Chapter 4 is concerned with modifications of the Jantzen-Plodinec hydration model which takes into account formation of complex aluminosilicate compounds in the glass. Chapter 5 is devoted to the development and validation of the structural-thermodynamic model for both durability and viscosity. This model assumes the strength of bonds between atoms to be the controlling factor in the composition dependence of these glass properties. The binding strengths are derived from the known heats of formation and the structural roles of constituent oxides. Since the coordination state of various oxides in the glass is temperature dependent and cation size has opposite effects on the two properties, the correlation between melt viscosity and rate of corrosion at low temperature is not simply linear. Chapter 6 surveys the effects of aqueous phase composition on the leach behavior of glasses. These studies provide a comprehensive view of the effects of both glass composition and leachant composition on leaching. The models developed correlate both durability and viscosity with glass composition. A major implication is that these findings can be used in the systematic optimization of the properties of complex oxide glasses

  19. Isotope effects of sulfur in chemical reactions

    International Nuclear Information System (INIS)

    Mikolajczuk, A.

    1999-01-01

    Sulfur is an important component of organic matter because it forms compounds with many elements. Due to high chemical activity of sulfur, it takes part in biological and geological processes in which isotope effects are occurring. It has been shown during last years research of isotope effects that we have take into account not only mass difference but also many other physical properties of nuclides e.g. even or odd number of neutrons in nuclei, shape and distribution of charge, turn of nuclear spin etc. The factor remains that new theoretical ideas have been formed on the base of data, being obtained in fractionation processes of heavy element isotope, particularly uranium. Now it is being well known that effects unconnected with vibration energy have also caused an effect on fractionation of considerably lighter elements like iron and magnesium. The important question is, if these effects would come to light during the separation of sulfur isotopes. Sulfur have three even isotopes M = (32, 34, 36) and one odd M 33). This problem is still open. (author)

  20. Effects of radiation on the chemical environment surrounding waste canisters in proposed repository sites and possible effects on the corrosion process

    International Nuclear Information System (INIS)

    Glass, R.S.

    1981-12-01

    This report explores the interaction of ionizing radiation with various environments. In particular, worst case (aqueous) environments for the proposed nuclear waste repository sites are considered. Emphasis is on the fundamental chemical and physical processes involved. The identities of possible radiolysis products (both transient and stable) have been sought through a literature search. The effect of radiation on corrosion processes is discussed. The radiation-induced chemical environment in the worst case repository sites is not well defined. Attention should therefore be given to fundamental studies exploring the interaction of such environments with components of the nuclear waste package, including the canister materials and backfills. Identification and quantification of radiolysis products would be helpful in this regard

  1. Analytical study in 1D nuclear waste migration

    International Nuclear Information System (INIS)

    Perez Guerrero, Jesus S.; Heilbron Filho, Paulo L.; Romani, Zrinka V.

    1999-01-01

    The simulation of the nuclear waste migration phenomena are governed mainly by diffusive-convective equation that includes the effects of hydrodynamic dispersion (mechanical dispersion and molecular diffusion), radioactive decay and chemical interaction. For some special problems (depending on the boundary conditions and when the domain is considered infinite or semi-infinite) an analytical solution may be obtained using classical analytical methods such as Laplace Transform or variable separation. The hybrid Generalized Integral Transform Technique (GITT) is a powerful tool that can be applied to solve diffusive-convective linear problems to obtain formal analytical solutions. The aim of this work is to illustrate that the GITT may be used to obtain an analytical formal solution for the study of migration of radioactive waste in saturated flow porous media. A case test considering 241 Am radionuclide is presented. (author)

  2. Chemical toxicity of uranium hexafluoride compared to acute effects of radiation

    International Nuclear Information System (INIS)

    McGuire, S.A.

    1991-02-01

    The chemical effects from acute exposures to uranium hexafluoride are compared to the nonstochastic effects from acute radiation doses of 25 rems to the whole body and 300 rems to the thyroid. The analysis concludes that an intake of about 10 mg of uranium in soluble form is roughly comparable, in terms of early effects, to an acute whole body dose of 25 rems because both are just below the threshold for significant nonstochastic effects. Similarly, an exposure to hydrogen fluoride at a concentration of 25 mg/m 3 for 30 minutes is roughly comparable because there would be no significant nonstochastic effects. For times t other than 30 minutes, the concentration C of hydrogen fluoride considered to have the same effect can be calculated using a quadratic equation: C = 25 mg/m 3 (30 min/t). The purpose of these analyses is to provide information for developing design and siting guideline based on chemical toxicity for enrichment plants using uranium hexafluoride. These guidelines are to be similar, in terms of stochastic health effects, to criteria in NRC regulations of nuclear power plants, which are based on radiation doses. 26 refs., 1 fig., 5 tabs

  3. Chemical toxicity of uranium hexafluoride compared to acute effects of radiation

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, S.A.

    1991-02-01

    The chemical effects from acute exposures to uranium hexafluoride are compared to the nonstochastic effects from acute radiation doses of 25 rems to the whole body and 300 rems to the thyroid. The analysis concludes that an intake of about 10 mg of uranium in soluble form is roughly comparable, in terms of early effects, to an acute whole body dose of 25 rems because both are just below the threshold for significant nonstochastic effects. Similarly, an exposure to hydrogen fluoride at a concentration of 25 mg/m{sup 3} for 30 minutes is roughly comparable because there would be no significant nonstochastic effects. For times t other than 30 minutes, the concentration C of hydrogen fluoride considered to have the same effect can be calculated using a quadratic equation: C = 25 mg/m{sup 3} (30 min/t). The purpose of these analyses is to provide information for developing design and siting guideline based on chemical toxicity for enrichment plants using uranium hexafluoride. These guidelines are to be similar, in terms of stochastic health effects, to criteria in NRC regulations of nuclear power plants, which are based on radiation doses. 26 refs., 1 fig., 5 tabs.

  4. Chemical modifications of liquid natural rubber

    Science.gov (United States)

    Azhar, Nur Hanis Adila; Rasid, Hamizah Md; Yusoff, Siti Fairus M.

    2016-11-01

    Liquid natural rubber (LNR) was synthesized via photosentisized degradation of natural rubber (NR). LNR was modified into epoxidized liquid natural rubber (LENR) and hydroxylated liquid natural rubber (LNR-OH) using Na2WO4/CH3COOH/H2O2 catalytic system. Chemical structures of LNR and modified LNRs were characterized using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) and 1H Nuclear Magnetic Resonance (NMR) spectroscopies. Integration of 1H NMR was used to calculate the epoxy content (%) of LENR. 1H NMR detected the formation of LNR-OH after prolonged heating and increased of catalyst in oxidation reaction.

  5. Tautomeric transformation of temozolomide, their proton affinities and chemical reactivities: A theoretical approach.

    Science.gov (United States)

    Sang-Aroon, Wichien; Ruangpornvisuti, Vithaya; Amornkitbamrung, Vittaya

    2016-05-01

    The gas-phase geometry optimizations of bare, mono- and dihydrated complexes of temozolomide isomers were carried out using density functional calculation at the M06-2X/6-31+G(d,p) level of the theory. The structures and protonation energies of protonated species of temozolomide are reported. Chemical indices of all isomers and protonated species are also reported. Energies, thermodynamic quantities, rate constants and equilibrium constants of tautomeric and rotameric transformations of all isomers I1↔TZM↔HIa↔HIb↔I2↔I3 in bare and hydrated systems were obtained. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Chemical and spectroscopic characterization of a vegetable oil used as dielectric coolant in distribution transformers

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Neffer A.; Abonia, Rodrigo, E-mail: rodrigo.abonia@correounivalle.edu.co [Departamento de Quimica, Escuela de Ingenieria Electrica, Universidad del Valle, Cali (Colombia); Cadavid, Hector [Grupo GRALTA, Escuela de Ingenieria Electrica, Universidad del Valle, Cali (Colombia); Vargas, Ines H. [Area de Ingenieria de Distribucion, Empresas Publicas de Medellin (EPM), Medellin (Colombia)

    2011-09-15

    In this work, a complete UV-Vis, IR and (1H, 13C and DEPT) NMR spectroscopic analysis was performed for a FR3 vegetable oil sample used as dielectric coolant in an experimental distribution transformer. The same spectroscopic analysis was performed for three used FR3 oil samples (i.e., 4 months in use, 8 months in use and 7 years in use), removed from several operating distribution transformers. Comparison of the data indicated that no significant spectroscopic changes, and hence, no structural changes occurred to the oils by the use. Chemical transformations like catalytic hydrogenation (hardening) and hydrolysis were performed to the FR3 oil sample and the obtained products were analyzed by spectroscopic methods in order to collect further structural information about the FR3 oil. Accelerated aging tests in laboratory were also performed for three FR3 oil samples affording interesting information about the structure of the degradation products. These findings would be valuable to search for a spectroscopy-based technique for monitoring the lifetime and performance of this insulating vegetable oil. (author)

  7. Neural network analysis of nuclear waste glass composition vs durability

    International Nuclear Information System (INIS)

    Seibel, C.K.

    1994-01-01

    The relationship between the chemical composition of oxide glasses and their physical properties is poorly understood, but it is becoming more important as vitrification (transformation into glass) of high-level nuclear waste becomes the favored method for long-term storage. The vitrified waste will be stored deep in geologic repositories where it must remain intact for at least 10,000 years. A strong resistance to groundwater exposure; i.c. a slow rate of glass dissolution, is of great importance. This project deals specifically with glass samples developed and tested for the nuclear fuel reprocessing facility near West Valley, New York. This facility needs to dispose of approximately 2.2 million liters of high-level radioactive liquid waste currently stored in stainless steel tanks. A self-organizing, artificial neural network was used to analyze the trends in the glass dissolution data for the effects of composition and the resulting durability of borosilicate glasses in an aqueous environment. This durability data can be used to systematically optimize the properties of the complex nuclear glasses and slow the dissolution rate of radionuclides into the environment

  8. Journal of Chemical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences. Mangala Sunder Krishnan. Articles written in Journal of Chemical Sciences. Volume 119 Issue 5 September 2007 pp 417-422. Effective Floquet Hamiltonian for spin = 1 in magic angle spinning NMR using contact transformation · Manoj Kumar Pandey Mangala Sunder ...

  9. [Construction of research system for processing mechanism of traditional Chinese medicine based on chemical composition transformation combined with intestinal absorption barrier].

    Science.gov (United States)

    Sun, E; Xu, Feng-Juan; Zhang, Zhen-Hai; Wei, Ying-Jie; Tan, Xiao-Bin; Cheng, Xu-Dong; Jia, Xiao-Bin

    2014-02-01

    Based on practice of Epimedium processing mechanism for many years and integrated multidisciplinary theory and technology, this paper initially constructs the research system for processing mechanism of traditional Chinese medicine based on chemical composition transformation combined with intestinal absorption barrier, which to form an innovative research mode of the " chemical composition changes-biological transformation-metabolism in vitro and in vivo-intestinal absorption-pharmacokinetic combined pharmacodynamic-pharmacodynamic mechanism". Combined with specific examples of Epimedium and other Chinese herbal medicine processing mechanism, this paper also discusses the academic thoughts, research methods and key technologies of this research system, which will be conducive to systematically reveal the modem scientific connotation of traditional Chinese medicine processing, and enrich the theory of Chinese herbal medicine processing.

  10. A guide to the effects of nuclear irradiation on materials, electronic and electrical components, oils and greases

    International Nuclear Information System (INIS)

    Lewis, R.C.E.

    1983-03-01

    A review is given of the effects of radiation on a selection of materials. Potentially damaging radiation thresholds are listed. The information has been taken from 12 documents for which references are given. The results of a study comparing component fault rates for nuclear and non-nuclear chemical plant are presented. (U.K.)

  11. Isotope effects on chemical shifts in tautomeric systems with double proton transfer. Citronin

    International Nuclear Information System (INIS)

    Hansen, P.E.; Langgard, M.; Bolvig, S.

    1998-01-01

    Primary and secondary deuterium isotope effects on 1 H and 13 C chemical shifts are measured in citrinin, a tautomeric compound with an unusual doubly intramolecularly hydrogen bonded structure. The isotope effects are to a large extent dominated by equilibrium contributions and deuteration leads to more of the deuterated enol forms rather than the deuterated acid form. 1 H 13 C and 17 O nuclear shieldings are calculated using density functional ab initio methods. A very good correlation between calculated nuclear shieldings and experimental 1 H and 13 C chemical shifts is obtained. The tautomeric equilibrium can be analyzed based on the isotope effects on B-6 and C-8 carbons and shows an increase in the o-quinone form on lowering the temperature. Furthermore, upon deuteration the largest equilibrium shift is found for deuteration at OH-8 and the shift in the tautomeric equilibrium upon deuteration at OH-8 and the shift in the tautomeric equilibrium upon deuteration is increasing at lower temperature. (author)

  12. Historical Exposures to Chemicals at the Rocky Flats Nuclear Weapons Plant: A Pilot Retrospective Exposure Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Janeen Denise [Univ. of New Mexico, Albuquerque, NM (United States)

    1999-02-01

    In a mortality study of white males who had worked at the Rocky Flats Nuclear Weapons Plant between 1952 and 1979, an increased number of deaths from benign and unspecified intracranial neoplasms was found. A case-control study nested within this cohort investigated the hypothesis that an association existed between brain tumor death and exposure to either internally deposited plutonium or external ionizing radiation. There was no statistically significant association found between estimated radiation exposure from internally deposited plutonium and the development of brain tumors. Exposure by job or work area showed no significant difference between the cohort and the control groups. An update of the study found elevated risk estimates for (1) all lymphopoietic neoplasms, and (2) all causes of death in employees with body burdens greater than or equal to two nanocuries of plutonium. There was an excess of brain tumors for the entire cohort. Similar cohort studies conducted on worker populations from other plutonium handling facilities have not yet shown any elevated risks for brain tumors. Historically, the Rocky Flats Nuclear Weapons Plant used large quantities of chemicals in their production operations. The use of solvents, particularly carbon tetrachloride, was unique to Rocky Flats. No investigation of the possible confounding effects of chemical exposures was done in the initial studies. The objectives of the present study are to (1) investigate the history of chemical use at the Rocky Flats facility; (2) locate and analyze chemical monitoring information in order to assess employee exposure to the chemicals that were used in the highest volume; and (3) determine the feasibility of establishing a chemical exposure assessment model that could be used in future epidemiology studies.

  13. Preparation and properties of the magnetic absorbent polymer via the chemical transformation process

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shengyu, E-mail: liusytyut@sina.com [Department of Mineral Processing, College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Key Laboratory of In-situ Property-improving Mining of Ministry of Education, Taiyuan University of Technology, Taiyuan 030024 (China); Zhang, Suhong, E-mail: zhangsh04@sina.com [Department of Mineral Processing, College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Guo, Jianying; Wen, Jing; Qiao, Yan [Department of Mineral Processing, College of Mining Engineering, Taiyuan University of Technology, Taiyuan 030024 (China)

    2017-01-15

    Magnetic polyacrylic acid sodium polymer (MPAAS) was prepared by chemical transformation method. Key parameters were investigated in the synthesis process of the magnetic polymer and an optimum preparation condition was gained. The structure of the magnetic polymer was characterized by X-ray diffraction (XRD), Fourier transform infrared spectrosocopy (FTIR) and scanning electron microscope (SEM). Magnetic property of the magnetic polymer was measured by the magnet and superconducting quantum interference device (SQUID). Both the swelling ratio and kinetics and the water retention ratio and kinetics were investigated. Based on the results, it can be gained that both swelling rate and equilibrium swelling rate were lowered after magnetization while the water retention ability of the magnetic polymer is stronger than that of the polymer. - Highlights: • The preparation mechanism of the magnetic polymer was proposed. • The magnetic property of the magnetic polymer was related to reaction conditions. • Swelling ratio and kinetics of polymer and magnetic polymer were studied. • Water retention ratio and kinetics of polymer and magnetic polymer were studied.

  14. Preparation and properties of the magnetic absorbent polymer via the chemical transformation process

    International Nuclear Information System (INIS)

    Liu, Shengyu; Zhang, Suhong; Guo, Jianying; Wen, Jing; Qiao, Yan

    2017-01-01

    Magnetic polyacrylic acid sodium polymer (MPAAS) was prepared by chemical transformation method. Key parameters were investigated in the synthesis process of the magnetic polymer and an optimum preparation condition was gained. The structure of the magnetic polymer was characterized by X-ray diffraction (XRD), Fourier transform infrared spectrosocopy (FTIR) and scanning electron microscope (SEM). Magnetic property of the magnetic polymer was measured by the magnet and superconducting quantum interference device (SQUID). Both the swelling ratio and kinetics and the water retention ratio and kinetics were investigated. Based on the results, it can be gained that both swelling rate and equilibrium swelling rate were lowered after magnetization while the water retention ability of the magnetic polymer is stronger than that of the polymer. - Highlights: • The preparation mechanism of the magnetic polymer was proposed. • The magnetic property of the magnetic polymer was related to reaction conditions. • Swelling ratio and kinetics of polymer and magnetic polymer were studied. • Water retention ratio and kinetics of polymer and magnetic polymer were studied.

  15. A solid-state nuclear magnetic resonance study of post-plasma reactions in organosilicone microwave plasma-enhanced chemical vapor deposition (PECVD) coatings.

    Science.gov (United States)

    Hall, Colin J; Ponnusamy, Thirunavukkarasu; Murphy, Peter J; Lindberg, Mats; Antzutkin, Oleg N; Griesser, Hans J

    2014-06-11

    Plasma-polymerized organosilicone coatings can be used to impart abrasion resistance and barrier properties to plastic substrates such as polycarbonate. Coating rates suitable for industrial-scale deposition, up to 100 nm/s, can be achieved through the use of microwave plasma-enhanced chemical vapor deposition (PECVD), with optimal process vapors such as tetramethyldisiloxane (TMDSO) and oxygen. However, it has been found that under certain deposition conditions, such coatings are subject to post-plasma changes; crazing or cracking can occur anytime from days to months after deposition. To understand the cause of the crazing and its dependence on processing plasma parameters, the effects of post-plasma reactions on the chemical bonding structure of coatings deposited with varying TMDSO-to-O2 ratios was studied with (29)Si and (13)C solid-state magic angle spinning nuclear magnetic resonance (MAS NMR) using both single-pulse and cross-polarization techniques. The coatings showed complex chemical compositions significantly altered from the parent monomer. (29)Si MAS NMR spectra revealed four main groups of resonance lines, which correspond to four siloxane moieties (i.e., mono (M), di (D), tri (T), and quaternary (Q)) and how they are bound to oxygen. Quantitative measurements showed that the ratio of TMDSO to oxygen could shift the chemical structure of the coating from 39% to 55% in Q-type bonds and from 28% to 16% for D-type bonds. Post-plasma reactions were found to produce changes in relative intensities of (29)Si resonance lines. The NMR data were complemented by Fourier transform infrared (FTIR) spectroscopy. Together, these techniques have shown that the bonding environment of Si is drastically altered by varying the TMDSO-to-O2 ratio during PECVD, and that post-plasma reactions increase the cross-link density of the silicon-oxygen network. It appears that Si-H and Si-OH chemical groups are the most susceptible to post-plasma reactions. Coatings produced at a

  16. Renormalization transformation of periodic and aperiodic lattices

    International Nuclear Information System (INIS)

    Macia, Enrique; Rodriguez-Oliveros, Rogelio

    2006-01-01

    In this work we introduce a similarity transformation acting on transfer matrices describing the propagation of elementary excitations through either periodic or Fibonacci lattices. The proposed transformation can act at two different scale lengths. At the atomic scale the transformation allows one to express the systems' global transfer matrix in terms of an equivalent on-site model one. Correlation effects among different hopping terms are described by a series of local phase factors in that case. When acting on larger scale lengths, corresponding to short segments of the original lattice, the similarity transformation can be properly regarded as describing an effective renormalization of the chain. The nature of the resulting renormalized lattice significantly depends on the kind of order (i.e., periodic or quasiperiodic) of the original lattice, expressing a delicate balance between chemical complexity and topological order as a consequence of the renormalization process

  17. Effect of Ni Addition on Bainite Transformation and Properties in a 2000 MPa Grade Ultrahigh Strength Bainitic Steel

    Science.gov (United States)

    Tian, Junyu; Xu, Guang; Jiang, Zhengyi; Hu, Haijiang; Zhou, Mingxing

    2018-05-01

    The effects of Nickle (Ni) addition on bainitic transformation and property of ultrahigh strength bainitic steels are investigated by three austempering processes. The results indicate that Ni addition hinders the isothermal bainite transformation kinetics, and decreases the volume fraction of bainite due to the decrease of chemical driving force for nucleation and growth of bainite transformation. Moreover, the product of tensile strength and total elongation (PSE) of high carbon bainitic steels decreases with Ni addition at higher austempering temperatures (220 and 250 °C), while it shows no significant difference at lower austempering temperature (200 °C). For the same steel (Ni-free or Ni-added steel), the amounts of bainite and RA firstly increase and then decrease with the increase of the austempering temperature, resulting in the highest PSE in the sample austempered at temperature of 220 °C. In addition, the effects of austempering time on bainite amount and property of high carbon bainitic steels are also analyzed. It indicates that in a given transformation time range of 30 h, more volume of bainite and better mechanical property in high carbon bainitic steels can be obtained by increasing the isothermal transformation time.

  18. Stable Chemical Dosimeters for Partial Reconstruction of Nuclear Accident Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Dvornik, I.; Zec, U.; Baric, M.; Razem, D. [Ruder Boskovic Nuclear Institute, Zagreb, Yugoslavia (Croatia)

    1969-10-15

    The application of chemical dosimeters, tissue equivalent with respect to gamma rays and neutrons, is proposed for dosimetric topography of the space around nuclear devices in case of accidents. The dosimeters in the form of sealed glass ampoules have sufficient sensitivity and long-term stability and are evaluated or checked directly by conventional spectrophotometry. The sensitivity, expressed as yield per rad, is approximately equal for gamma rays and neutrons. The resolution in both cases is about one rad, and the range is up to several thousand rads. The precision of dosimetry is {+-} 1 rad or {+-} 2%, whichever is higher. In free space and unshielded the dosimeter measures the total rad-absorbed dose delivered by gamma rays and neutrons, i.e. the first collision gamma plus neutron dose. If used on- or in-phantom, especially if several dosimeters are disposed within and around the same phantom, it can give important data about the amount of the neutron component of the dose and about the effective mean energy of incident neutrons. The neutron component of the dose can be directly measured if the gamma dosimeter is used together with the chemical dosimeter. The experiments giving the change of optical density per rad and the radiation chemical yield with respect to the absorbed dose delivered by 14-MeV neutrons are described in detail. The possibility is also mentioned of applying the dosimeter as a very sensitive monitor for thermal neutrons, which is due to the chlorine content of 4.73% and activation to {sup 38}Cl. The opinion is expressed that this dosimeter deserves some attention as a part of future planning and development work on area and personnel accidental dosimetry systems. (author)

  19. Characterisation of Authentic Lignin Biorefinery Samples by Fourier Transform Infrared Spectroscopy and Determination of the Chemical Formula for Lignin

    DEFF Research Database (Denmark)

    Le, Duy Michael; Damgaard Nielsen, Anders; Sørensen, Hanne

    2017-01-01

    samples in situ with no prior purification and minimal sample preparation. Lignin chemical formulas and lignin Fourier transform infrared (FTIR) spectra were extracted from mixed spectra by filtering out signals from residual carbohydrates and minerals. From estimations of C, H and O and adjustment...

  20. Compensation effects in molecular interactions and the quantum chemical le Chatelier principle.

    Science.gov (United States)

    Mezey, Paul G

    2015-05-28

    Components of molecular interactions and various changes in the components of total energy changes during molecular processes typically exhibit some degrees of compensation. This may be as prominent as the over 90% compensation of the electronic energy and nuclear repulsion energy components of the total energy in some conformational changes. Some of these compensations are enhanced by solvent effects. For various arrangements of ions in a solvent, however, not only compensation but also a formal, mutual enhancement between the electronic energy and nuclear repulsion energy components of the total energy may also occur, when the tools of nuclear charge variation are applied to establish quantum chemically rigorous energy inequalities.

  1. Nuclear famine: The indirect effects of nuclear war

    International Nuclear Information System (INIS)

    Harwell, M.A.; Harwell, C.C.

    1986-01-01

    The indirect effects of a nuclear war, especially as mediated by disruption in food availability, could be much more extensive than the direct effects. Furthermore, this risk is especially severe for noncombatant countries - for the 4 billion or so humans expected to survive the immediate period after a nuclear war relatively physically unharmed. Thus, a fundamentally different picture of the post-nuclear-war world results, where a large-scale nuclear war between the United States and the Soviet Union would probably result in more eventual fatalities in India than in the United States and the Soviet Union combined, and more people would die on the African continent than in all of Europe. Rather than reflecting images of Hiroshima and Nagasaki, a modern nuclear war would, for most of the people of the world, much more resemble current images of Ethiopia and the Sudan

  2. Finite size effects in liquid-gas phase transition of asymmetric nuclear matter

    International Nuclear Information System (INIS)

    Pawlowski, P.

    2001-01-01

    Full text: Since the nuclear equation of state has been studied in astrophysical context as an element of neutron star or super-nova theories - a call for an evidence was produced in experimental nuclear physics. Heavy-ion collisions became a tool of study on thermodynamic properties of nuclear matter. A particular interest has been inspired here by critical behavior of nuclear systems, as a phase transition of liquid-gas type. A lot of efforts was put to obtain an experimental evidence of such a phenomenon in heavy-ion collisions. With the use of radioactive beams and high performance identification systems in a near future it will be possible to extend experimental investigation to asymmetric nuclear systems, where neutron-to-proton ratio is far from the stability line. This experimental development needs a corresponding extension of theoretical studies. To obtain a complete theory of the liquid-gas phase transition in small nuclear systems, produced in violent heavy-ion collisions, one should take into account two facts. First, that the nuclear matter forming nuclei is composed of protons and neutrons; this complicates the formalism of phase transitions because one has to deal with two separate, proton and neutron, densities and chemical potentials. The second and more important is that the surface effects are very strong in a system composed of a few hundreds of nucleons. This point is especially difficult to hold, because surface becomes an additional, independent state parameter, depending strongly on the geometrical configuration of the system, and introducing a non-local term in the equation of state. In this presentation we follow the recent calculation by Lee and Mekjian on the finite-size effects in small (A = 10 2 -10 3 ) asymmetric nuclear systems. A zero-range isospin-dependent Skyrme force is used to obtain a density and isospin dependent potential. The potential is then completed by additional terms giving contributions from surface and Coulomb

  3. Modernization of the Electric Power Systems (transformers, rods and switches) in the Laguna Verde Nuclear Power Plant (Mexico)

    International Nuclear Information System (INIS)

    Gonzalez Solarzano, J. J.; Gabaldon Martin, M. A.; Pallisa Nunez, J.; Florez Ordeonez, A.; Fernandez Corbeira, A.; Prieto Diez, I.

    2010-01-01

    Description of the changes made in the Electric Power Systems as a part of the power increase project in the Laguna Verde Nuclear Power Plant (Mexico). The main electrical changes to make, besides the turbo group, are the main generation transformers, the isolated rods and the generation switch.

  4. Effects of oxygen and misonidazole on cell transformation and cell killing in C3H 10T1/2 cells by X rays in vitro

    International Nuclear Information System (INIS)

    Borsa, J.; Sargent, M.D.; Einspenner, M.; Azzam, E.I.; Raaphorst, G.P.

    1984-01-01

    The effects of oxygen (air) and misonidazole on the transformation and killing of 10T1/2 cells by X rays were examined. The oxygen effect for the cell transformation end point was very similar to that for cell killing. Misonidazole enhanced both cell killing and cell transformation to a similar extent. The enhancement of both end points by misonidazole occurred only in the absence of oxygen during irradiation and was of lesser magnitude than that observed for oxygen. These results demonstrate that the radiation chemical processes leading to cell killing and cell transformation, respectively, are affected similarly by these two enhancers of radiation action. 22 references, 3 figures, 2 tables

  5. Short-circuit tests of 1650 and 96 MVA transformers for 1300 MW french nuclear power plants

    International Nuclear Information System (INIS)

    Mailhot, M.

    1989-01-01

    Power evacuation and feeding of the auxiliaries directly from the 400 kV grid are sensitive points governing the security of 1300 MW PWR Nuclear Power Plants of the French Program. These two different functions are provided by two specific types of transformers. - Banks of 3 single-phase 550 MVA - 400 kV/20 kV transformers. - Three-phase 96 MVA - 400 kV / 3 x 6.8 kV transformers. These passive elements must have a never failing reliability and assure a continuous service in spite of electric, thermal and mechanical stresses that may occur during the lifetime of the power plant. Dielectric and thermal tests carried out in the manufacturers test floors insure these stresses withstand capabilities of transformers. In France, high short-circuit power for the 400 kV network added to often low impedance voltages for transformers impose on them very high stresses during short-circuits. Calculation and experimentation on scale or partial models are not sufficient to insure short-circuit currents withstand capabilities of transformers. The margin of uncertainty dependent on obligatory extrapolations for this kind of complex systems [steel, magnetic sheets, copper, oil, paper and transformerboard] can be reduced in a significant way only by real scale tests on prototypes. These tests that need both high power and voltage cannot be performed in manufacturers test floors. So, in France they are carried out at the EDF Les Renardieres Laboratory. Following paper deals with SHELL TYPE TRANSFORMERS which, particularly thanks to their interleaved rectangular windings display a great resistance to short-circuit stresses

  6. Effect of heavy atoms on photochemically induced dynamic nuclear polarization in liquids

    Science.gov (United States)

    Okuno, Yusuke; Cavagnero, Silvia

    2018-01-01

    Given its short hyperpolarization time (∼10-6 s) and mostly non-perturbative nature, photo-chemically induced dynamic nuclear polarization (photo-CIDNP) is a powerful tool for sensitivity enhancement in nuclear magnetic resonance. In this study, we explore the extent of 1H-detected 13C nuclear hyperpolarization that can be gained via photo-CIDNP in the presence of small-molecule additives containing a heavy atom. The underlying rationale for this methodology is the well-known external-heavy-atom (EHA) effect, which leads to significant enhancements in the intersystem-crossing rate of selected photosensitizer dyes from photoexcited singlet to triplet. We exploited the EHA effect upon addition of moderate amounts of halogen-atom-containing cosolutes. The resulting increase in the transient triplet-state population of the photo-CIDNP sensitizer fluorescein resulted in a significant increase in the nuclear hyperpolarization achievable via photo-CIDNP in liquids. We also explored the internal-heavy-atom (IHA) effect, which is mediated by halogen atoms covalently incorporated into the photosensitizer dye. Widely different outcomes were achieved in the case of EHA and IHA, with EHA being largely preferable in terms of net hyperpolarization.

  7. In vitro nuclear receptor inhibition and cytotoxicity of hydraulic fracturing chemicals and their binary mixtures.

    Science.gov (United States)

    Bain, Peter A; Kumar, Anu

    2018-05-01

    The widespread use of hydraulic fracturing (HF) in oil and gas extraction operations has led to concern over environmental risks posed by chemicals used in HF fluids. Here we employed a suite of stable luciferase reporter gene assays to investigate the potential for selected HF chemicals or geogenics to activate or antagonise nuclear receptor signalling. We screened three biocides (bronopol [BP], glutaraldehyde [GA], and tetrakis(hydroxymethyl)phosphonium sulfate [THPS]), a surfactant (2-butoxyethanol), a friction reducer (polyacrylamide), and a coal seam geogenic (o-cresol) for their potential to act as agonists or antagonists of the estrogen receptor, androgen receptor, progesterone receptor (PR), glucocorticoid receptor or peroxisome proliferator-activated receptor gamma (PPARγ). None of the chemicals induced luciferase activity in any of assays used in the study. In antagonistic mode, BP, GA and THPS caused reductions in luciferase activity in the reporter assays at higher concentrations (50-100 μM), while at low concentrations (2-10 μM) GA and THPS enhanced luciferase activity in some assays relative to controls. None of the other tested chemicals exhibited antagonism in the selected assays. In most cases, altered receptor signalling only occurred at concentrations exhibiting cytotoxicity. However, PPARγ activity, and to a lesser extent PR activity, were inhibited by THPS at sub-cytotoxic concentrations. The majority of binary combinations tested exhibited significantly less-than-additive cytotoxicity, and none of the combinations exhibited synergistic cytotoxicity. In summary, the results of the present study indicate that the selected chemicals are not likely to function as direct agonists of the nuclear receptors tested, and only one chemical, THPS was an apparent partial antagonist of two nuclear receptors. Copyright © 2017. Published by Elsevier Ltd.

  8. Bounds on the entanglement attainable from unitary transformed thermal states in liquid-state nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Yu, Terri M.; Brown, Kenneth R.; Chuang, Isaac L.

    2005-01-01

    The role of mixed-state entanglement in liquid-state nuclear magnetic resonance (NMR) quantum computation is not yet well understood. In particular, despite the success of quantum-information processing with NMR, recent work has shown that quantum states used in most of those experiments were not entangled. This is because these states, derived by unitary transforms from the thermal equilibrium state, were too close to the maximally mixed state. We are thus motivated to determine whether a given NMR state is entanglable - that is, does there exist a unitary transform that entangles the state? The boundary between entanglable and nonentanglable thermal states is a function of the spin system size N and its temperature T. We provide bounds on the location of this boundary using analytical and numerical methods; our tightest bound scales as N∼T, giving a lower bound requiring at least N∼22 000 proton spins to realize an entanglable thermal state at typical laboratory NMR magnetic fields. These bounds are tighter than known bounds on the entanglability of effective pure states

  9. Factors in low-carbon energy transformations: Comparing nuclear and bioenergy in Brazil, Sweden, and the United States

    International Nuclear Information System (INIS)

    Hultman, Nathan E.; Malone, Elizabeth L.; Runci, Paul; Carlock, Gregory; Anderson, Kate L.

    2012-01-01

    Policies to address climate change by reducing greenhouse gas emissions might be made more effective if we can better understand the pathways by which transformative technologies become significant components of energy systems. Indeed, the central question of mitigation revolves around the scope of policy to influence or accelerate the diffusion of low-carbon technology. While market forces clearly influence technology deployment, understanding the longer-term and large-scale changes in the energy system requires a broader understanding of the relative influence of institutional, behavioral, and social factors. This paper presents the results of an interview-based, comparative case approach to investigating systematically the relative importance of these non-economic factors influencing technological change across technology and country contexts. We identified two low-carbon energy sectors (bioenergy and nuclear power) that underwent significant changes over the past 50 years in the energy portfolio of three countries: Brazil, Sweden, and the United States. We identified nine categories of factors that might contribute to these large technological transformations, and then evaluated, via interviews with sector participants in each country, which factors were viewed as being determinative or highly influential in the trajectory of that technology in their country context. We also draw out policy implications and directions for future research. - Highlights: ► Study of energy transformations in bioenergy and nuclear energy in Brazil, Sweden, and the US. ► Data include survey and 78 interviews across 3 countries and 2 sectors. ► Across all countries and sectors, domestic policy was seen as the major factor in transitions. ► Other key factors with more variance were technological characteristics and industry structure. ► Study adds empirical detail to understanding of relative weights of factors in energy transitions.

  10. Nuclear security in a transformed world

    International Nuclear Information System (INIS)

    Gottfried, K.; Dean, J.

    1991-01-01

    In the wake of the failed coup attempt in the Soviet Union, the world stands hopeful that a new era of international peace and cooperation lies ahead. President Bush's unilateral reductions in tactical nuclear weapons and in the alert levels of US forces, coupled with President Gorbachev's largely reciprocal actions, are important steps toward realizing that hope. While bold in the context of recent arms control history, however, these actions are modest in the face of the current enormous opportunity and the shifting threats the world now faces. Even with these welcome unilateral actions, the likely continued presence of thousands of nuclear weapons throughout many of the Soviet republics, the temporary uncertainty over central government command during the coup, and fuller knowledge of Iraq's aggressive efforts to build a nuclear bomb serve as stark reminders that the danger of nuclear catastrophe has not disappeared. Although a deliberate attack by the Soviet Union against the US or Europe is now almost inconceivable, nuclear weapons continue to pose significant threats to US security and world peace. These threats fall into three broad categories: a persistent risk of regional nuclear war involving countries other than the Soviet Union that are already in possession of nuclear weapons or capable of building them; the spread of nuclear weapons to other countries; accidental or unauthorized use. To meet this new challenge, three key steps must be taken: reduce dramatically Soviet and US nuclear arsenals; negotiate restrictions on the arsenals of other nuclear powers; strengthen the nuclear nonproliferation regime

  11. Theoretical Study of H/D Isotope Effects on Nuclear Magnetic Shieldings Using an ab initio Multi-Component Molecular Orbital Method

    Directory of Open Access Journals (Sweden)

    Masanori Tachikawa

    2013-05-01

    Full Text Available We have theoretically analyzed the nuclear quantum effect on the nuclear magnetic shieldings for the intramolecular hydrogen-bonded systems of σ-hydroxy acyl aromatic species using the gauge-including atomic orbital technique combined with our multi-component density functional theory. The effect of H/D quantum nature for geometry and nuclear magnetic shielding changes are analyzed. Our study clearly demonstrated that the geometrical changes of hydrogen-bonds induced by H/D isotope effect (called geometrical isotope effect: GIE is the dominant factor of deuterium isotope effect on 13C chemical shift.

  12. The chemical transformation of calcium in Shenhua coal during combustion in a muffle furnace

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Sida [North China Electric Power Univ., Beijing (China). School of Energy, Power and Mechanical Engineering; Ministry of Education, Beijing (China). Key Lab. of Condition Monitoring and Control for Power Plant Equipment; Zhuo, Yuqun; Chen, Changhe [Tsinghua Univ., Beijing (China). Dept. of Thermal Engineering; Ministry of Education, Beijing (China). Key Lab. for Thermal Science and Power Engineering; Shu, Xinqian [China Univ. of Mining and Technology, Beijing (China). School of Chemical and Environmental Engineering

    2013-07-01

    The chemical reaction characteristics of calcium in three samples of Shenhua coal, i.e. raw sample, hydrochloric acid washed sample and hydrochloric acid washed light fraction, during combustion in a muffle furnace have been investigated in this paper. Ca is bound by calcite and organic matter in Shenhua coal. X ray diffraction (XRD) phase analysis has been conducted to these samples' combustion products obtained by heating at different temperatures. It has been found that the organically-bound calcium could easily react with clays and transform into gehlenite and anorthite partially if combusted under 815 C, whilst the excluded minerals promoted the conversion of gehlenite to anorthite. Calcite in Shenhua coal decomposed into calcium oxide and partially transformed into calcium sulfate under 815 C, and formed gehlenite and anorthite under 1,050 C. Calcite and other HCl-dissolved minerals in Shenhua coal were responsible mainly for the characteristic that the clay minerals in Shenhua coal hardly became mullite during combustion.

  13. Chemical transformations of chlorophyll and its application in the design of a new generation of environmentally safe dyes

    International Nuclear Information System (INIS)

    Berezin, Boris D; Rumyantseva, Svetlana V; Moryganov, Andrey P; Berezin, Mikhail B

    2004-01-01

    Chemical transformations of chlorophyll and physicochemical properties of its derivatives are considered. These compounds can be used in the design of a new generation of chlorophyll- and porphyrin-based dyes environmentally more safe than currently used arene dyes and possessing renewable sources of raw materials. The first results on the use of chlorophyll derivatives for dyeing wool, acetate fibres and cotton are reported.

  14. Chemical transformations of chlorophyll and its application in the design of a new generation of environmentally safe dyes

    Energy Technology Data Exchange (ETDEWEB)

    Berezin, Boris D; Rumyantseva, Svetlana V; Moryganov, Andrey P; Berezin, Mikhail B [Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo (Russian Federation)

    2004-02-28

    Chemical transformations of chlorophyll and physicochemical properties of its derivatives are considered. These compounds can be used in the design of a new generation of chlorophyll- and porphyrin-based dyes environmentally more safe than currently used arene dyes and possessing renewable sources of raw materials. The first results on the use of chlorophyll derivatives for dyeing wool, acetate fibres and cotton are reported.

  15. Organic Nitrogen in Atmospheric Drops and Particles: Concentrations, (Limited) Speciation, and Chemical Transformations

    Science.gov (United States)

    Anastasio, C.; Zhang, Q.

    2003-12-01

    While quite a bit is known of the concentrations, speciation, and chemistry of inorganic forms of nitrogen in the atmosphere, the same cannot be said for organic forms. Despite this, there is growing evidence that organic N (ON) is ubiquitous in the atmosphere, especially in atmospheric condensed phases such as fog/cloud drops and aerosol particles. Although the major compounds that make up organic N are generally unknown, as are the sources of these compounds, it is clear that there are significant fluxes of ON between the atmosphere and ecosystems. It also appears that organic N can have significant effects in both spheres. The goal of our recent work in this area has been to better describe the atmospheric component of the biogeochemistry of organic nitrogen. Based on particle, gas, and fogwater samples from Northern California we have made three major findings: 1) Organic N represents a significant component, approximately 20%, of the total atmospheric N loading in these samples. This is broadly consistent with studies from other locations. 2) Amino compounds, primarily as combined amino acids, account for approximately 20% of the measured ON in our condensed phase samples. Given the properties of amino acids, these compounds could significantly affect the chemical and physical properties of atmospheric particles. 3) Organic nitrogen in atmospheric particles and drops is transformed to inorganic forms - primarily ammonium, nitrate, and nitrogen oxides (NOx) - during exposure to sunlight and/or ozone. These chemical reactions likely increase the bioavailability of the condensed phase nitrogen pool and enhance its biological effects after deposition to ecosystems.

  16. Study of seed layer effect in nuclear battery with P-N diode junction

    Energy Technology Data Exchange (ETDEWEB)

    Uhm, Young Rang; Son, Kwang Jae; Lee, Jun Sig [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Choi, Byoung Gun [Kookmin Univ., Seoul (Korea, Republic of)

    2014-10-15

    A nuclear battery with diode junction is a device that converts nuclear radiation directly to electric power. The mechanism of a nuclear battery is same as the P-N junction diode for solar cell application. The photovoltaic is operated by converted photons to electrical energy in the junction. In betavoltaic battery, beta particles are collected and converted to electrical energy as similar principle as photovoltaic. A very low current, order of nano or micro amps, is generated in devices. If a radioisotope (RI) with a long halflife (over 50 years) is used, a lifetime of a power source is extended as long as halflife time of RI.. Some special applications require long-lived compact power sources. These include space equipment, sensors in remote locations (space, underground, etc.), and implantable medical devices. Conventionally, these sources rely on converting chemical energy to electricity. This means they require a large storage of chemical 'fuel' since the amount of energy released per reaction is small. The nuclear battery is a novel solution to solve the power needs of these applications. For the {sup 63}Ni beta-source we used, the half-life is 100.2 years. Hence, the power sources we describe could extend a system's operating life by several decades or even a century, during which time the system could gain learned behavior without worrying about the power turning off. Radioactive thin-film-based power sources also have energy density orders of magnitude higher than chemical-reaction-based energy sources. In this study, we fabricate nuclear battery using {sup 63}Ni source with diode junction, and studied seed layer effect for optimization of structure of p-n junction.

  17. Radiological equivalent of chemical pollutants

    International Nuclear Information System (INIS)

    Medina, V.O.

    1982-01-01

    The development of the peaceful uses of nuclear energy has caused continued effort toward public safety through radiation health protection measures and nuclear management practices. However, concern has not been focused on the development specifically in the operation of chemical pestrochemical industries as well as other industrial processes brought about by technological advancements. This article presents the comparison of the risk of radiation and chemicals. The methods used for comparing the risks of late effects of radiation and chemicals are considered at three levels. (a) as a frame of reference to give an impression of resolving power of biological tests; (b) as methods to quantify risks; (c) as instruments for an epidemiological survey of human populations. There are marked dissimilarities between chemicals and radiation and efforts to interpret chemical activity may not be achieved. Applicability of the concept of rad equivalence has many restrictions and as pointed out this approach is not an established one. (RTD)

  18. Basic Research Needs for Advanced Nuclear Systems. Report of the Basic Energy Sciences Workshop on Basic Research Needs for Advanced Nuclear Energy Systems, July 31-August 3, 2006

    Energy Technology Data Exchange (ETDEWEB)

    Roberto, J.; Diaz de la Rubia, T.; Gibala, R.; Zinkle, S.; Miller, J.R.; Pimblott, S.; Burns, C.; Raymond, K.; Grimes, R.; Pasamehmetoglu, K.; Clark, S.; Ewing, R.; Wagner, A.; Yip, S.; Buchanan, M.; Crabtree, G.; Hemminger, J.; Poate, J.; Miller, J.C.; Edelstein, N.; Fitzsimmons, T.; Gruzalski, G.; Michaels, G.; Morss, L.; Peters, M.; Talamini, K.

    2006-10-01

    The global utilization of nuclear energy has come a long way from its humble beginnings in the first sustained nuclear reaction at the University of Chicago in 1942. Today, there are over 440 nuclear reactors in 31 countries producing approximately 16% of the electrical energy used worldwide. In the United States, 104 nuclear reactors currently provide 19% of electrical energy used nationally. The International Atomic Energy Agency projects significant growth in the utilization of nuclear power over the next several decades due to increasing demand for energy and environmental concerns related to emissions from fossil plants. There are 28 new nuclear plants currently under construction including 10 in China, 8 in India, and 4 in Russia. In the United States, there have been notifications to the Nuclear Regulatory Commission of intentions to apply for combined construction and operating licenses for 27 new units over the next decade. The projected growth in nuclear power has focused increasing attention on issues related to the permanent disposal of nuclear waste, the proliferation of nuclear weapons technologies and materials, and the sustainability of a once-through nuclear fuel cycle. In addition, the effective utilization of nuclear power will require continued improvements in nuclear technology, particularly related to safety and efficiency. In all of these areas, the performance of materials and chemical processes under extreme conditions is a limiting factor. The related basic research challenges represent some of the most demanding tests of our fundamental understanding of materials science and chemistry, and they provide significant opportunities for advancing basic science with broad impacts for nuclear reactor materials, fuels, waste forms, and separations techniques. Of particular importance is the role that new nanoscale characterization and computational tools can play in addressing these challenges. These tools, which include DOE synchrotron X

  19. Basic Research Needs for Advanced Nuclear Systems. Report of the Basic Energy Sciences Workshop on Basic Research Needs for Advanced Nuclear Energy Systems, July 31-August 3, 2006

    International Nuclear Information System (INIS)

    Roberto, J.; Diaz de la Rubia, T.; Gibala, R.; Zinkle, S.; Miller, J.R.; Pimblott, S.; Burns, C.; Raymond, K.; Grimes, R.; Pasamehmetoglu, K.; Clark, S.; Ewing, R.; Wagner, A.; Yip, S.; Buchanan, M.; Crabtree, G.; Hemminger, J.; Poate, J.; Miller, J.C.; Edelstein, N.; Fitzsimmons, T.; Gruzalski, G.; Michaels, G.; Morss, L.; Peters, M.; Talamini, K.

    2006-01-01

    The global utilization of nuclear energy has come a long way from its humble beginnings in the first sustained nuclear reaction at the University of Chicago in 1942. Today, there are over 440 nuclear reactors in 31 countries producing approximately 16% of the electrical energy used worldwide. In the United States, 104 nuclear reactors currently provide 19% of electrical energy used nationally. The International Atomic Energy Agency projects significant growth in the utilization of nuclear power over the next several decades due to increasing demand for energy and environmental concerns related to emissions from fossil plants. There are 28 new nuclear plants currently under construction including 10 in China, 8 in India, and 4 in Russia. In the United States, there have been notifications to the Nuclear Regulatory Commission of intentions to apply for combined construction and operating licenses for 27 new units over the next decade. The projected growth in nuclear power has focused increasing attention on issues related to the permanent disposal of nuclear waste, the proliferation of nuclear weapons technologies and materials, and the sustainability of a once-through nuclear fuel cycle. In addition, the effective utilization of nuclear power will require continued improvements in nuclear technology, particularly related to safety and efficiency. In all of these areas, the performance of materials and chemical processes under extreme conditions is a limiting factor. The related basic research challenges represent some of the most demanding tests of our fundamental understanding of materials science and chemistry, and they provide significant opportunities for advancing basic science with broad impacts for nuclear reactor materials, fuels, waste forms, and separations techniques. Of particular importance is the role that new nanoscale characterization and computational tools can play in addressing these challenges. These tools, which include DOE synchrotron X

  20. Lessons Learned on University Education Programs of Chemical Engineering Principles for Nuclear Plant Operations - 13588

    International Nuclear Information System (INIS)

    Ryu, Jun-hyung

    2013-01-01

    University education aims to supply qualified human resources for industries. In complex large scale engineering systems such as nuclear power plants, the importance of qualified human resources cannot be underestimated. The corresponding education program should involve many topics systematically. Recently a nuclear engineering program has been initiated in Dongguk University, South Korea. The current education program focuses on undergraduate level nuclear engineering students. Our main objective is to provide industries fresh engineers with the understanding on the interconnection of local parts and the entire systems of nuclear power plants and the associated systems. From the experience there is a huge opportunity for chemical engineering disciple in the context of giving macroscopic overview on nuclear power plant and waste treatment management by strengthening the analyzing capability of fundamental situations. (authors)

  1. Introduction to nuclear chemistry

    International Nuclear Information System (INIS)

    Lieser, K.H.

    1980-01-01

    The study in this book begins with the periodic system of elements (chapter 1). The physical fundamentals necessary to understand nuclear chemistry are dealt with in chapter 2. Chapter 3 and 4 treat the influence of the mass number on the chemical behaviour (isotope effect) and the isotope separation methods thus based on this effect. A main topic is studied in chapter 5, the laws of radioactive decay, a second main topic is dealt with in chapter 8, nuclear reactions. The chemical effects of nuclear reactions are treated on their own chapter 9. Radiochemical reactions which are partly closely linked to the latter are only briefly discussed in chapter 10. The following chapters discuss the various application fields of nuclear chemistry. The large apparatus indispensable for nuclear chemistry is dealt with in a special chapter (chapter 12). Chapter 15 summarizes the manifold applications. (orig.) [de

  2. Cea-Expo: A facility exposure matrix to assess passed exposure to chemical carcinogens and radionuclides of nuclear workers

    International Nuclear Information System (INIS)

    Telle-Lamberton, M.; Bouville, P.; Bergot, D.; Gagneau, M.; Marot, S.; Telle-Lamberton, M.; Giraud, J.M.; Gelas, J.M.

    2005-01-01

    A 'Facility-Exposure Matrix' (FEM) is proposed to assess exposure to chemical carcinogens and radionuclides in a cohort of nuclear workers. Exposures are to be attributed in the following way: a worker reports to an administrative unit and/or is monitored for exposure to ionising radiation in a specific workplace. These units are connected with a list of facilities for which exposure is assessed through a group of experts. The entire process of the FEM applied in one of the nuclear centres included in the study shows that the FEM is feasible: exposure durations as well as groups of correlated exposures are presented but have to be considered as possible rather than positive exposures. Considering the number of facilities to assess (330), ways to simplify the method are proposed: (i) the list of exposures will be restricted to 18 chemical products retained from an extensive bibliography study; (ii) for each of the following classes of facilities: nuclear reactors, fuel fabrication, high-activity laboratories and radiation chemistry, accelerators and irradiators, waste treatment, biology, reprocessing, fusion, occupational exposure will be deduced from the information already gathered by the initial method. Besides taking into account confusion factors in the low doses epidemiological study of nuclear workers, the matrix should help in the assessment of internal contamination and chemical exposures in the nuclear industry. (author)

  3. Effects of the fluid flows on enzymatic chemical oscillations

    Science.gov (United States)

    Shklyaev, Oleg; Yashin, Victor; Balazs, Anna

    2017-11-01

    Chemical oscillations are ubiquitous in nature and have a variety of promising applications. Usually, oscillating chemical systems are analyzed within the context of a reaction-diffusion framework. Here, we examine how fluid flows carrying the reactants can be utilized to modulate the negative feedback loops and time delays that promote chemical oscillations. We consider a model where a chemical reaction network involves two species, X and Y, which undergo transformations catalyzed by respective enzymes immobilized at the bottom wall of a fluid-filled microchamber. The reactions with the enzymes provide a negative feedback in the chemically oscillating system. In particular, the first enzyme, localized on the first patch, promotes production of chemical X, while the second enzyme, immobilized on the second patch, promotes production of chemical Y, which inhibits the production of chemical X. The separation distance between the enzyme-coated patches sets the time delay required for the transportation of X and Y. The chemical transport is significantly enhanced if convective fluxes accompany the diffusive ones. Therefore, the parameter region where oscillations are present is modified. The findings provide guidance to designing micro-scale chemical reactors with improved functionalities.

  4. Chemical transformations of characteristic hop secondary metabolites in relation to beer properties and the brewing process: a review.

    Science.gov (United States)

    Steenackers, Bart; De Cooman, Luc; De Vos, Dirk

    2015-04-01

    The annual production of hops (Humulus lupulus L.) exceeds 100,000 mt and is almost exclusively consumed by the brewing industry. The value of hops is attributed to their characteristic secondary metabolites; these metabolites are precursors which are transformed during the brewing process into important bittering, aromatising and preservative components with rather low efficiency. By selectively transforming these components off-line, both their utilisation efficiency and functionality can be significantly improved. Therefore, the chemical transformations of these secondary metabolites will be considered with special attention to recent advances in the field. The considered components are the hop alpha-acids, hop beta-acids and xanthohumol, which are components unique to hops, and alpha-humulene and beta-caryophyllene, sesquiterpenes which are highly characteristic of hops. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Physical and toxic properties of hazardous chemicals regularly stored and transported in the vicinity of nuclear installations

    International Nuclear Information System (INIS)

    1976-03-01

    This report gives a compilation of data based on information assembled by the US Nuclear Regulatory Commission and completed by the Safety and Reliability Directorate of the UK AEA, the Dutch Reactor Safety Commission, the French Atomic Energy Commission, and the CSNI Secretariat. Data sheets for a large number of hazardous chemicals are presented (from acetaldehyde to xylene), giving details of their physical and toxic properties such as: molecular weight, boiling point, vapor density, heat of vaporization, toxic concentration in air, flammability limits, toxic effects, vapor pressure data, etc.

  6. Chemical, Biological, Radiological and Nuclear Regional Centres of Excellence Initiative

    International Nuclear Information System (INIS)

    Bril, L.V.

    2013-01-01

    This series of slides presents the initiative launched in May 2010 by the European Union to develop at national and regional levels the necessary institutional capacity to fight against the CBRN (Chemical, Biological, Radiological and Nuclear) risk. The origin of the risk can be: -) criminal (proliferation, theft, sabotage and illicit traffics), -) accidental (industrial catastrophes, transport accidents...) and -) natural (mainly pandemics). The initiative consists in the creation of Centres of Excellence for providing assistance and cooperation in the field of CBRN risk and the creation of experts networks for sharing best practices, reviewing laws and regulation, developing technical capacities in order to mitigate the CBRN risk. The initiative is complementary to the instrument for nuclear safety cooperation. Regional Centres of Excellence are being set up in 6 regions: South East Europe, South East Asia, North Africa, West Africa, Middle East, and Central Asia covering nearly 40 countries. A global budget of 100 million Euros will be dedicated to this initiative for the 2009-2013 period. (A.C.)

  7. New fundamental equations of thermodynamics for systems in chemical equilibrium at a specified partial pressure of a reactant and the standard transformed formation properties of reactants

    International Nuclear Information System (INIS)

    Alberty, R.A.; Oppenheim, I.

    1993-01-01

    When temperature, pressure, and the partial pressure of a reactant are fixed, the criterion of chemical equilibrium can be expressed in terms of the transformed Gibbs energy G' that is obtained by using a Legendre transform involving the chemical potential of the reactant that is fixed. For reactions of ideal gases, the most natural variables to use in the fundamental equation are T, P', and P B , where P' is the partial pressure of the reactants other than the one that is fixed and P B is the partial pressure of the reactant that is fixed. The fundamental equation for G' yields the expression for the transformed entropy S', and a transformed enthalpy can be defined by the additional Legendre transform H'=G'+TS'. This leads to an additional form of the fundamental equation. The calculation of transformed thermodynamic properties and equilibrium compositions is discussed for a simple system and for a general multireaction system. The change, in a reaction, of the binding of the reactant that is at a specified pressure can be calculated using one of the six Maxwell equations of the fundamental equation in G'

  8. Several perspectives on water-chemical cycles for nuclear power stations equipped with type VVER and RBMK reactors

    International Nuclear Information System (INIS)

    Mamet, A.P.; Mamet, V.A.; Pashevich, V.I.; Nazarenko, P.N.

    1982-01-01

    Water-chemical cycles for loops I and II of VVER reactors are discussed. These cycles are mixed ammonia-sodium with a variable concentration of boric acid and ammonia hydrazine with a pH factor of 9.1 +/- 0.1. New water-chemical cycles are considered for use in both existing and new nuclear power plants. Application of these new water-chemical cycles showed produce a significant improvement in operating conditions of nuclear power plants. Upon accumulation of sufficient operating experience with these cycles, it should be possible to raise the issue of revising applicable standard documentation

  9. The effects on the atmosphere of a major nuclear exchange

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    Most of the earth's population would survive the immediate horrors of a nuclear holocaust, but what long-term climatological changes would affect their ability to secure food and shelter. This sobering report considers the effects of fine dust from ground-level detonations, of smoke from widespread fires, and of chemicals released into the atmosphere. The authors use mathematical models of atmospheric processes and data from natural situations - e.g., volcanic eruptions and arctic haze - to draw their conclusions

  10. About possibility of creation of ecologically pure, safe nuclear power plants on the basis of high-effective resonant neutron interaction with splitting substances

    International Nuclear Information System (INIS)

    Irdyncheyev, L.A.; Malofeyev, A.M.; Frid, E.S.; Abramov, E.P.

    1993-01-01

    Currently the most important problem in nuclear engineering is creation of ecologically pure, safe nuclear power plants in the context of real danger of global ecological pollution of the environment with long-lived fission products and the resultant transuranium nuclides. The problem can be solved by creating nuclear power plants on the basis of high-effective resonant interaction (HERI). Such power plants would provide the total cycle, including nuclear fuel production (Plutonium-239 from Uranium-238), combustion and waste products salvaging by way of transformation of radioactive nuclides into stable isotopes

  11. Theoretical study of chemical reaction effects on vertical oscillating plate with variable temperature

    Directory of Open Access Journals (Sweden)

    Muthucumaraswamy R.

    2006-01-01

    Full Text Available An exact solution to the flow of a viscous incompressible unsteady flow past an infinite vertical oscillating plate with variable temperature and mass diffusion is presented here, taking into account of the homogeneous chemical reaction of first-order. Both the plate temperature and the concentration level near the plate are raised linearly with respect to time. The dimensionless governing equations has been obtained by the Laplace transform method, when the plate is oscillating harmonically in its own plane. The effects of velocity and concentration are studied for different parameters like phase angle, chemical reaction parameter, thermal Grashof number, mass Grashof number, Schmidt number and time are studied. The solutions are valid only for small values of time t. It is observed that the velocity increases with decreasing phase angle ωt or chemical reaction parameter. .

  12. Chemical speciation of U, Fe, and Pu in melt glass from nuclear weapons testing

    Energy Technology Data Exchange (ETDEWEB)

    Pacold, J. I.; Lukens, W. W.; Booth, C. H.; Shuh, D. K. [Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Knight, K. B.; Eppich, G. R. [Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Holliday, K. S. [Materials Science Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2016-05-21

    Nuclear weapons testing generates large volumes of glassy materials that influence the transport of dispersed actinides in the environment and may carry information on the composition of the detonated device. We determine the oxidation state of U and Fe (which is known to buffer the oxidation state of actinide elements and to affect the redox state of groundwater) in samples of melt glass collected from three U.S. nuclear weapons tests. For selected samples, we also determine the coordination geometry of U and Fe, and we report the oxidation state of Pu from one melt glass sample. We find significant variations among the melt glass samples and, in particular, find a clear deviation in one sample from the expected buffering effect of Fe(II)/Fe(III) on the oxidation state of uranium. In the first direct measurement of Pu oxidation state in a nuclear test melt glass, we obtain a result consistent with existing literature that proposes Pu is primarily present as Pu(IV) in post-detonation material. In addition, our measurements imply that highly mobile U(VI) may be produced in significant quantities when melt glass is quenched rapidly following a nuclear detonation, though these products may remain immobile in the vitrified matrices. The observed differences in chemical state among the three samples show that redox conditions can vary dramatically across different nuclear test conditions. The local soil composition, associated device materials, and the rate of quenching are all likely to affect the final redox state of the glass. The resulting variations in glass chemistry are significant for understanding and interpreting debris chemistry and the later environmental mobility of dispersed material.

  13. Chemical speciation of U, Fe, and Pu in melt glass from nuclear weapons testing

    Science.gov (United States)

    Pacold, J. I.; Lukens, W. W.; Booth, C. H.; Shuh, D. K.; Knight, K. B.; Eppich, G. R.; Holliday, K. S.

    2016-05-01

    Nuclear weapons testing generates large volumes of glassy materials that influence the transport of dispersed actinides in the environment and may carry information on the composition of the detonated device. We determine the oxidation state of U and Fe (which is known to buffer the oxidation state of actinide elements and to affect the redox state of groundwater) in samples of melt glass collected from three U.S. nuclear weapons tests. For selected samples, we also determine the coordination geometry of U and Fe, and we report the oxidation state of Pu from one melt glass sample. We find significant variations among the melt glass samples and, in particular, find a clear deviation in one sample from the expected buffering effect of Fe(II)/Fe(III) on the oxidation state of uranium. In the first direct measurement of Pu oxidation state in a nuclear test melt glass, we obtain a result consistent with existing literature that proposes Pu is primarily present as Pu(IV) in post-detonation material. In addition, our measurements imply that highly mobile U(VI) may be produced in significant quantities when melt glass is quenched rapidly following a nuclear detonation, though these products may remain immobile in the vitrified matrices. The observed differences in chemical state among the three samples show that redox conditions can vary dramatically across different nuclear test conditions. The local soil composition, associated device materials, and the rate of quenching are all likely to affect the final redox state of the glass. The resulting variations in glass chemistry are significant for understanding and interpreting debris chemistry and the later environmental mobility of dispersed material.

  14. A transformation theory of stochastic evolution in Red Moon methodology to time evolution of chemical reaction process in the full atomistic system.

    Science.gov (United States)

    Suzuki, Yuichi; Nagaoka, Masataka

    2017-05-28

    Atomistic information of a whole chemical reaction system, e.g., instantaneous microscopic molecular structures and orientations, offers important and deeper insight into clearly understanding unknown chemical phenomena. In accordance with the progress of a number of simultaneous chemical reactions, the Red Moon method (a hybrid Monte Carlo/molecular dynamics reaction method) is capable of simulating atomistically the chemical reaction process from an initial state to the final one of complex chemical reaction systems. In the present study, we have proposed a transformation theory to interpret the chemical reaction process of the Red Moon methodology as the time evolution process in harmony with the chemical kinetics. For the demonstration of the theory, we have chosen the gas reaction system in which the reversible second-order reaction H 2 + I 2  ⇌ 2HI occurs. First, the chemical reaction process was simulated from the initial configurational arrangement containing a number of H 2 and I 2 molecules, each at 300 K, 500 K, and 700 K. To reproduce the chemical equilibrium for the system, the collision frequencies for the reactions were taken into consideration in the theoretical treatment. As a result, the calculated equilibrium concentrations [H 2 ] eq and equilibrium constants K eq at all the temperatures were in good agreement with their corresponding experimental values. Further, we applied the theoretical treatment for the time transformation to the system and have shown that the calculated half-life τ's of [H 2 ] reproduce very well the analytical ones at all the temperatures. It is, therefore, concluded that the application of the present theoretical treatment with the Red Moon method makes it possible to analyze reasonably the time evolution of complex chemical reaction systems to chemical equilibrium at the atomistic level.

  15. Absence of PDGF-induced, PKC-independent c-fos expression in a chemically transformed C3H/10T1/2 cell clone.

    Science.gov (United States)

    Vassbotn, F S; Skar, R; Holmsen, H; Lillehaug, J R

    1992-09-01

    The effect of platelet-derived growth factor (PDGF) on c-fos mRNA transcription was studied in the immortalized mouse embryo fibroblast C3H/10T1/2 Cl 8 (10T1/2) cells and the chemically transformed, tumorigenic subclone C3H/10T1/2 Cl 16 (Cl 16). In the 10T1/2 cells as well as the Cl 16 subclone, the dose-dependent PDGF stimulation of c-fos mRNA synthesis was similar in both logarithmically growing and confluent cultures. c-fos mRNA was induced severalfold by 12-O-tetradecanoylphorbol-13-acetate (TPA) in both 10T1/2 and Cl 16. Down-regulation of protein kinase C (PKC) activity by TPA pretreatment inhibited PDGF-stimulated c-fos mRNA expression in Cl 16 cells but did not affect this induction in the 10T1/2 cells. This inhibition was not a general phenomenon of 3-methylcholanthrene-mediated transformation of 10T1/2 cells since experiments with another transformed 10T1/2 cell clone, C3H/10T1/2 TPA 482, gave qualitatively the same results as the 10T1/2 cells. Receptor binding experiments showed that the nontransformed and transformed cells had a comparable number of PDGF receptors, 1.3 x 10(5) and 0.7 x 10(5) receptors per cell, respectively. Furthermore, cAMP-induced c-fos expression induced by forskolin is formerly shown to be independent of PKC down-regulation. In our experiments, forskolin induced c-fos expression in both clones. However, PKC down-regulation inhibited the forskolin-induced c-fos expression in Cl 16 cells. This apparently demonstrates cross talk between PKC and PKA in the c-fos induction pathway. The present results provide evidence for an impaired mechanism for activating c-fos expression through PKC-independent, PDGF-induced signal transduction in the chemically transformed Cl 16 fibroblasts compared to that in nontransformed 10T1/2 cells.

  16. [Chemical weapons and chemical terrorism].

    Science.gov (United States)

    Nakamura, Katsumi

    2005-10-01

    Chemical Weapons are kind of Weapons of Mass Destruction (WMD). They were used large quantities in WWI. Historically, large quantities usage like WWI was not recorded, but small usage has appeared now and then. Chemical weapons are so called "Nuclear weapon for poor countrys" because it's very easy to produce/possession being possible. They are categorized (1) Nerve Agents, (2) Blister Agents, (3) Cyanide (blood) Agents, (4) Pulmonary Agents, (5) Incapacitating Agents (6) Tear Agents from the viewpoint of human body interaction. In 1997 the Chemical Weapons Convention has taken effect. It prohibits chemical weapons development/production, and Organization for the Prohibition of Chemical Weapons (OPCW) verification regime contributes to the chemical weapons disposal. But possibility of possession/use of weapons of mass destruction by terrorist group represented in one by Matsumoto and Tokyo Subway Sarin Attack, So new chemical terrorism countermeasures are necessary.

  17. Limit power of nuclear fuel cells with biconcave cross sections

    International Nuclear Information System (INIS)

    Alves, Thiago Antonini; Pelegrini, Marcelo Ferreira; Woiski, Emanuel Rocha; Maia, Cassio Roberto Macedo

    2004-01-01

    Diffusive media with distributed sources, such as the case of nuclear fuel cells, represent a major role in engineering. Due to the nuclear fission of the chemical element, fuel cells are capable of releasing an enormous amount of thermal energy in spite of their reduced dimensions, in such a way that the maximum power of the reactor is closely related to the fusion temperature of the fuel, and consequently to the maximum temperature in the cell. The cell maximum temperature is, therefore, a chief parameter in nuclear reactor design. Limiting power, of course, depends not only of the fuel thermo physical properties, but also of the cell shape and dimensions. The present work purports the study of the effects of some parameters of cell geometry on the limiting power, especially for cell with biconcave cross sections. Given the large temperature gradients in the cell, the thermal conductivity must be assumed as a generic function of temperature. Therefore, the problem has been modeled as a nonlinear 2 D Poisson-like PDE, with a nontrivial geometry of the boundary. For the analytical solution, Kirchhoff transform has been employed to turn the equation into a linear Poisson equation, a conformal transform brought it to a rectangular domain and Generalized Integral Transform method applied in order to solve the resulting equation. For the numerical solution of the linearized equation, a program has been developed in Python, reusing classes of Ellipt2d, an open-source elliptic solver. The domain has been divided into linear triangular finite elements, and the system of equations resulting of Galerkin method application has been solved, for each parameter set. The trend in critical power has been discussed, as well as the numerical results compared to the analytical solutions and to the literature. (author)

  18. Designing new nuclear chemical processing plants for safeguards accountability

    International Nuclear Information System (INIS)

    Sprouse, K.M.

    1987-01-01

    New nuclear chemical processing plants will be required to develop material accountability control limits from measurement error propagation analysis rather than historical inventory difference data as performed in the past. In order for measurement error propagation methods to be viable alternatives, process designers must ensure that two nondimensional accountability parameters are maintained below 0.1. These parameters are ratios between the material holdup increase and the variance in inventory difference measurement uncertainty. Measurement uncertainty data for use in error propagation analysis is generally available in the open literature or readily derived from instrument calibration data. However, nuclear material holdup data has not been adequately developed for use in the material accountability design process. Long duration development testing on isolated unit operations is required to generate this necessary information

  19. Cellular and molecular mechanisms of chronic rhinosinusitis and potential therapeutic strategies: review on cytokines, nuclear factor kappa B and transforming growth factor beta.

    Science.gov (United States)

    Phan, N T; Cabot, P J; Wallwork, B D; Cervin, A U; Panizza, B J

    2015-07-01

    Chronic rhinosinusitis is characterised by persistent inflammation of the sinonasal mucosa. Multiple pathophysiological mechanisms are likely to exist. Previous research has focused predominantly on T-helper type cytokines to highlight the inflammatory mechanisms. However, proteins such as nuclear factor kappa B and transforming growth factor beta are increasingly recognised to have important roles in sinonasal inflammation and tissue remodelling. This review article explores the roles of T-helper type cytokines, nuclear factor kappa B and transforming growth factor beta in the pathophysiological mechanisms of chronic rhinosinusitis. An understanding of these mechanisms will allow for better identification and classification of chronic rhinosinusitis endotypes, and, ultimately, improved therapeutic strategies.

  20. An integrated multi-label classifier with chemical-chemical interactions for prediction of chemical toxicity effects.

    Science.gov (United States)

    Liu, Tao; Chen, Lei; Pan, Xiaoyong

    2018-05-31

    Chemical toxicity effect is one of the major reasons for declining candidate drugs. Detecting the toxicity effects of all chemicals can accelerate the procedures of drug discovery. However, it is time-consuming and expensive to identify the toxicity effects of a given chemical through traditional experiments. Designing quick, reliable and non-animal-involved computational methods is an alternative way. In this study, a novel integrated multi-label classifier was proposed. First, based on five types of chemical-chemical interactions retrieved from STITCH, each of which is derived from one aspect of chemicals, five individual classifiers were built. Then, several integrated classifiers were built by integrating some or all individual classifiers. By testing the integrated classifiers on a dataset with chemicals and their toxicity effects in Accelrys Toxicity database and non-toxic chemicals with their performance evaluated by jackknife test, an optimal integrated classifier was selected as the proposed classifier, which provided quite high prediction accuracies and wide applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. Detection of a nuclear, EBNA-type antigen in apparently EBNA-negative Herpesvirus papio (HVP)-transformed lymphoid lines by the acid-fixed nuclear binding technique.

    Science.gov (United States)

    Ohno, S; Luka, J; Falk, L; Klein, G

    1977-12-15

    In agreement with the findings of previous authors, we could not detect a virally determined nuclear antigen in Herpesvirus papio (HVP)-transformed baboon lymphoid lines by anticomplementary staining in situ, as for EBNA. However, by means of our recently developed acid-fixed nuclear binding technique an EBNA-like antigen could be readily demonstrated, after extraction from both producer and non-producer lines. We propose to designate the antigen as HUPNA. It can be detected by a human anti-EBNA antibody, suggesting cross-reactivity, if not identity, between EBNA and HUPNA. HVP-DNA carrying non-producer lines, negative for in situ ACIF stainability but capable of yielding HUPNA by the nuclear binding technique, can be superinfected with EBV, with brilliant EBNA expression as the result, suggesting that the defective in situ staining is a property associated with the baboon HVP, rather than the baboon lymphoid cell per se.

  2. The Department of Energy/American Chemical Society Summer School in Nuclear and Radiochemistry at San Jose State University

    International Nuclear Information System (INIS)

    Kinard, W.F.; Silber, H.B.

    2005-01-01

    A Summer School in Nuclear Chemistry sponsored by the U. S. Department of Energy and the American Chemical Society has been held at San Jose State University for the past 20 years. The intent of the program is to introduce outstanding college students to the field of nuclear and radiochemistry with the goal that some of these students will consider careers on nuclear science. The program features radiochemistry experiments along with radiation safety training, guest lectures by well known nuclear scientists and field trips to nuclear chemistry facilities in the San Francisco area. (author)

  3. Experience Transformed into Nuclear Regulatory Improvements in Russia

    International Nuclear Information System (INIS)

    Sapozhnikov, A.

    2016-01-01

    The third International Conference on Effective Nuclear Regulatory Systems (Canada, 2013) identified the main action items that should be addressed, implemented and followed up. The key technical and organizational areas important to strengthening reactor and spent fuel safety have been determined as following: • Regulatory lessons learned and actions taken (since the accident at the Fukushima Daiichi NPP); • Waste management and spent fuel safety; • Emergency management; • Emerging programmes; • Human and organizational factors, safety and security culture. Over time many activities based on results of the IAEA Integrated Regulatory Review Service in the Russian Federation, 2019, and post-mission, 2013, have been implemented. At present there is progress for the national action plan on nuclear safety, preparation and conducting of long term spent fuel management, complementary reviews for nuclear facilities other than Nuclear Power Plants, emergency exercises with the regulatory body participation, improving communication, development of national regulations and improvement of regulatory system in the whole. The regulatory body ensures assistance in development of national regulatory infrastructure, safety culture to the countries planning to construct Russian design facilities (NPPs, RRs). The report outlines the results and future actions to improve nuclear regulation based on systematic approach to safety and particularly reflects the specificity of taking measures for the research reactors. (author)

  4. Chemical Constraints Governing the Origin of Metabolism: The Thermodynamic Landscape of Carbon Group Transformations

    Science.gov (United States)

    Weber, Arthur L.; Fonda, Mark (Technical Monitor)

    2001-01-01

    The thermodynamics of organic chemistry under mild aqueous conditions was examined in order to begin to understand its influence on the structure and operation of metabolism and its antecedents. Free energies were estimated for four types reactions of biochemical importance carbon-carbon bond cleavage and synthesis, hydrogen transfer between carbon groups, dehydration of alcohol groups, and aldo-keto isomerization. The energies were calculated for mainly aliphatic groups composed of carbon, hydrogen, and oxygen. The energy values showed that (1) when carbon-carbon bond cleavage involves two different types of functional groups, transfer of the shared electron-pair to the more reduced carbon group is energetically favored over transfer to the more oxidized carbon group, and (2) the energy of carbon-carbon bond transformation is strongly dependent on the type of functional group that donates the shared electron-pair during cleavage, and the group that accepts the shared electron-pair during synthesis, and (3) the energetics of C-C bond transformation is determined primarily by the half-reaction energies of the couples: carbonyl/carboxylic acid, carboxylic acid/carbon dioxide, alcohol/carbonyl, and hydrocarbon/alcohol. The energy of hydrogen-transfer between carbon groups was found to depend on the functional group class of both the hydrogen-donor and hydrogen-acceptor. From these and other observations we concluded that the chemistry of the origin of metabolism (and to a lesser degree modem metabolism) is strongly constrained by the (1) limited disproportionation energy of organic substrates that can be dissipated in a few irreversible reactions, (2) the energy-dominance of few half-reaction couples in carbon-carbon bond transformation that establishes whether a chemical reaction is energetically irreversible, reversible or unfeasible, and (3) the dependence of the transformation-energy on the oxidation state of carbon groups (functional group type) which is

  5. Transformation processes influencing physico-chemical forms of radionuclides and trace elements in natural water systems

    International Nuclear Information System (INIS)

    Salbu, B.; Riise, G.; Oughton, D.H.

    1995-01-01

    In order to assess short and long term consequences of radionuclides and trace elements introduced to aquatic systems, knowledge on source terms, key factors and key processes influencing the speciation is essential. The mobility, bioavailability and subsequent transfer into food chains depend on the physico-chemical forms on radionuclides and trace metals. In addition, transformation processes and especially the interaction with natural organic matter (NOM) influences the distribution pattern. Furthermore, the prevailing climate conditions, e.g. episodic events and temperature are vital for fluxes and for the kinetics of the transformation processes. In the present work processes in catchments and processes associated with acidification, episodic events, climate conditions (temperature) and mixing zone phenomena influencing the speciation of radionuclides and trace metals are highlighted. These processes should be highly relevant for assessing far field consequences of radionuclides potentially released from disposal sites. (authors). 21 refs., 8 figs., 1 tab

  6. Monitoring systems online of oil for transformers of nuclear power plants; Sistemas de monitorizacion online del aceite para transformadores de potencia de Centrales

    Energy Technology Data Exchange (ETDEWEB)

    Sarandeses, S.

    2014-07-01

    The nuclear power plants are showing their concern due to the existence of recent failures related to the bulky transformers of power. These transformers are not security, but are important for the production of power as its failure can cause transient on the floor, reactor scram or shooting, that can cause interruptions in the production of energy or might force us to reduce the power of production The analysis of gases dissolved in transformer oil is recognized as a trial key to identify a submerged transformer failure in oil. With this analysis it is not possible to ensure that there is no damage in the transformer, but the probability of risk of this type of failure can be reduced. The industry recommended to equip the new large power transformers with oil online monitoring systems and in some cases also be It recommended its use in existing transformers. (Author)

  7. Fourier transform nuclear magnetic resonance studies of 199Hg

    International Nuclear Information System (INIS)

    Krueger, H.; Lutz, O.; Nolle, A.; Schwenk, A.

    1975-01-01

    199 Hg Fourier Transform NMR studies of various solutions of diverse mercury salts in H 2 O and D 2 O or in the appropriate protonated and deuterated acids are reported for both Hg 2 ++ and Hg ++ . In the different solutions investigated the 199 Hg line positions depend on the concentration of the solution, on the solvents and their isotopic composition and on the temperature of the sample. A ratio of the Larmor frequency of 199 Hg and of 2 H in a Hg(NO 3 ) 2 solution in dilute DNO 3 is given. Using this ratio and the measured chemical shifts, a ratio of the Larmor frequencies of 199 Hg for infinite dilution relative to 2 H in pure D 2 O is given. From this a g 1 -factor for 199 Hg is derived and compared with the g 1 -factor of an optical pumping experiment. The resulting shielding constant is sigma (hydrated 199 Hg ++ versus 199 Hg atom) = -24.32(5) x 10 -4 . This yields an atomic reference scale for all measured NMR line shifts of mercury. (orig.) [de

  8. EDF's approach to determine specifications for nuclear power plant bulk chemicals

    International Nuclear Information System (INIS)

    Basile, Alix; Dijoux, Michel; Le-Calvar, Marc; Gressier, Frederic; Mole, Didier

    2012-09-01

    Chemical impurities in the primary, secondary and auxiliary nuclear power plants circuits generate risks of corrosion of the fuel cladding, steel and nickel based alloys. The PMUC (Products and Materials Used in plants) organization established by EDF intends to limit this risk by specifying maximum levels of impurities in products and materials used for the operation and maintenance of Nuclear Power Plants (NPPs). Bulk chemicals specifications, applied on primary and secondary circuit chemicals and hydrogen and nitrogen gases, are particularly important to prevent chemical species to be involved in the corrosion of the NPPs materials. The application of EDF specifications should lead to reasonably exclude any risk of degradation of the first and second containment barriers and auxiliary circuits Important to Safety (IPS) by limiting the concentrations of chlorides, fluorides, sulfates... The risk of metal embrittlement by elements with low melting point (mercury, lead...) is also included. For the primary circuit, the specifications intend to exclude the risk of activation of impurities introduced by the bulk chemicals. For the first containment barrier, to reduce the risk of deposits like zeolites, PMUC products specifications set limit values for calcium, magnesium, aluminum and silica. EDF's approach for establishing specifications for bulk chemicals is taking also into account the capacity of industrial production, as well as costs, limitations of analytical control methods (detection limits) and environmental releases issues. This paper aims to explain EDF's approach relative to specifications of impurities in bulk chemicals. Also presented are the various parameters taken into account to determine the maximum pollution levels in the chemicals, the theoretical hypothesis to set the specifications and the calculation method used to verify that the specifications are suitable. (authors)

  9. In situ vitrification and the effects of soil additives

    International Nuclear Information System (INIS)

    Piepel, G.F.; Shade, J.W.

    1992-01-01

    This paper presents a case study involving in situ vitrification (ISV), a process for immobilizing chemical or nuclear wastes in soil by melting-dissolving the contaminated soil into a glass block. One goal of the study was to investigate how viscosity and electrical conductivity were affected by mixing CaO and Na 2 O with soil. A three-component constrained-region mixture experiment design was generated and the viscosity and electrical conductivity data collected. Several second-order mixture models were considered, and the Box-Cox transformation technique was applied to select property transformations. The fitted models were used to produce contour and component effects plots

  10. Stereoelectronic effects on 1H nuclear magnetic resonance chemical shifts in methoxybenzenes

    DEFF Research Database (Denmark)

    Lambert, Maja; Olsen, Lars; Jaroszewski, Jerzy W

    2006-01-01

    the Ar-OCH3 torsion out of the ring plane, resulting in large stereoelectronic effects on the chemical shift of Hpara. Conformational searches and geometry optimizations for 3-16 at the B3LYP/6-31G** level, followed by B3LYP/6-311++G(2d,2p) calculations for all low-energy conformers, gave excellent...

  11. Persistence of sister chromatid exchanges and in vitro morphological transformation of Syrian hamster fetal cells by chemical and physical carcinogens

    International Nuclear Information System (INIS)

    Popescu, N.C.; Amsbaugh, S.C.; DiPaolo, J.A.

    1985-01-01

    The induction of neoplastic cell transformation is closely associated with DNA alterations which occur shortly after carcinogen exposure. Sister chromatid exchange (SCE) formation is a sensitive indicator of carcinogen-DNA interaction and correlates with the induction of morphological cell transformation. The persistence of lesions generating SCE produced by chemical and physical carcinogens and its relevance to the induction of morphologic transformation was evaluated in coordinated experiments with cultured Syrian hamster fetal cells (HFC). Exponentially growing HFC were exposed for 1 h to benzo[a]pyrene (BP), methyl-methanesulfonate (MMS), cis-platinum (II) diaminedichloride (cis Pt II), N-methyl-N'-nitrosourea (MNU), mitomycin C (MMC), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), N-acetoxy-2-fluorenyl-acetamide (AcAAF) or u.v. light irradiated. SCE analysis demonstrates that for a period of 48 h after carcinogen exposure, during which time the cells undergo at least four replicative cycles, DNA damage generating SCE induced by all chemical carcinogens either persisted or was partially removed, whereas u.v.-induced lesions were completely removed. An elevated SCE frequency persisted after two additional cell cycles after treatment with BP, AcAAF or MMC without increased cell lethality as compared to other carcinogens whose lesions were completely eliminated during the same period

  12. Identification of Diethyl 2,5-Dioxahexane Dicarboxylate and Polyethylene Carbonate as Decomposition Products of Ethylene Carbonate Based Electrolytes by Fourier Transform Infrared Spectroscopy

    KAUST Repository

    Shi, Feifei; Zhao, Hui; Liu, Gao; Ross, Philip N.; Somorjai, Gabor A.; Komvopoulos, Kyriakos

    2014-01-01

    The formation of passive films on electrodes due to electrolyte decomposition significantly affects the reversibility of Li-ion batteries (LIBs); however, understanding of the electrolyte decomposition process is still lacking. The decomposition products of ethylene carbonate (EC)-based electrolytes on Sn and Ni electrodes are investigated in this study by Fourier transform infrared (FTIR) spectroscopy. The reference compounds, diethyl 2,5-dioxahexane dicarboxylate (DEDOHC) and polyethylene carbonate (poly-EC), were synthesized, and their chemical structures were characterized by FTIR spectroscopy and nuclear magnetic resonance (NMR). Assignment of the vibration frequencies of these compounds was assisted by quantum chemical (Hartree-Fock) calculations. The effect of Li-ion solvation on the FTIR spectra was studied by introducing the synthesized reference compounds into the electrolyte. EC decomposition products formed on Sn and Ni electrodes were identified as DEDOHC and poly-EC by matching the features of surface species formed on the electrodes with reference spectra. The results of this study demonstrate the importance of accounting for the solvation effect in FTIR analysis of the decomposition products forming on LIB electrodes. © 2014 American Chemical Society.

  13. Identification of Diethyl 2,5-Dioxahexane Dicarboxylate and Polyethylene Carbonate as Decomposition Products of Ethylene Carbonate Based Electrolytes by Fourier Transform Infrared Spectroscopy

    KAUST Repository

    Shi, Feifei

    2014-07-10

    The formation of passive films on electrodes due to electrolyte decomposition significantly affects the reversibility of Li-ion batteries (LIBs); however, understanding of the electrolyte decomposition process is still lacking. The decomposition products of ethylene carbonate (EC)-based electrolytes on Sn and Ni electrodes are investigated in this study by Fourier transform infrared (FTIR) spectroscopy. The reference compounds, diethyl 2,5-dioxahexane dicarboxylate (DEDOHC) and polyethylene carbonate (poly-EC), were synthesized, and their chemical structures were characterized by FTIR spectroscopy and nuclear magnetic resonance (NMR). Assignment of the vibration frequencies of these compounds was assisted by quantum chemical (Hartree-Fock) calculations. The effect of Li-ion solvation on the FTIR spectra was studied by introducing the synthesized reference compounds into the electrolyte. EC decomposition products formed on Sn and Ni electrodes were identified as DEDOHC and poly-EC by matching the features of surface species formed on the electrodes with reference spectra. The results of this study demonstrate the importance of accounting for the solvation effect in FTIR analysis of the decomposition products forming on LIB electrodes. © 2014 American Chemical Society.

  14. The impact of conventional and nuclear industries on the population A comparative study of the radioactive and chemical aspects

    CERN Document Server

    Coulon, R; Anguenot, F

    1988-01-01

    This study was carried out to make it possible to assess and localize in an objective manner the extent of the hazards and associated detrimental effects which are inherent in nuclear and non-nuclear industrial activities, among all the hazards to which the population of a given region is exposed. Rather than carry out a purely theoretical and speculative study a region was chosen as a basis to carry out a full- scale exercise, taking into account the existing real situation. The region chosen is situated in the south-east of France (Greater Rhone Delta) where almost all industrial activities can be found: electricity generating industries (thermal and nuclear power stations), the activities associated with them (extraction, processing, storage of waste, etc.) and industrial activities which are sources of pollution (refineries, chemical industries, etc.). To put the risks of all these activities (to workers, the public and the environment) in perspective, the case of other sources of risk, such as certain ag...

  15. The effects on the atmosphere of a major nuclear exchange

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    Most of the earth's population would survive the immediate horrors of a nuclear holocaust, but what long-term climatological changes would affect their ability to secure food and shelter. This sobering report considers the effects of fine dust from ground-level detonations, of smoke from widespread fires, and of chemicals released into the atmosphere. The authors use mathematical models of atmospheric processes and data from natural situations - e.g., volcanic eruptions and arctic haze - to draw their conclusions.

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

    International Nuclear Information System (INIS)

    Bachmann, Udo; Biederbick, Walter; Derakshani, Nahid

    2010-01-01

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

  17. A comparative study on the effective safety of nuclear technology in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Soh, Young Jin [Daegu University, Daegu (Korea); Kim, Young Pyoung [Korea University, Seoul (Korea); Jung, Yoon Soo [Myoungji University, Seoul (Korea); Chung, Ik Jae; Choi, Byung Sun [Seoul National University, Seoul (Korea)

    2001-12-01

    The main purpose of this research is to analyze Korean perception of nuclear risk in comparison with other technological risks. In order to understand the characteristics of risk perception, the concept of 'effective safety' is clarified and defined. This research also covers such issues as relative riskiness of major risks, risk attitude, risk attribution, behavioral pattern for risky situation, and risk knowledge. A nation-wide survey was conducted for this study with a sample size of 1870. It was based on the purposive quota sampling to compare nuclear risk and other technological risks selected are 6 groups of risk; nuclear risk, environmental risk, traffic risk, chemical materials, industrial safety, and other recent risks. Accross these groups, a total of 25 risks are examined. 52 refs., 14 figs., 125 tabs. (Author)

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

    International Nuclear Information System (INIS)

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

    1996-01-01

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

  19. Evidence of Non-local Chemical, Thermal and Gravitational Effects

    Directory of Open Access Journals (Sweden)

    Hu H.

    2007-04-01

    Full Text Available Quantum entanglement is ubiquitous in the microscopic world and manifests itself macroscopically under some circumstances. But common belief is that it alone cannot be used to transmit information nor could it be used to produce macroscopic non- local effects. Yet we have recently found evidence of non-local effects of chemical substances on the brain produced through it. While our reported results are under independent verifications by other groups, we report here our experimental findings of non-local chemical, thermal and gravitational effects in simple physical systems such as reservoirs of water quantum-entangled with water being manipulated in a remote reservoir. With the aids of high-precision instruments, we have found that the pH value, temperature and gravity of water in the detecting reservoirs can be non-locally affected through manipulating water in the remote reservoir. In particular, the pH value changes in the same direction as that being manipulated; the temperature can change against that of local environment; and the gravity apparently can also change against local gravity. These non-local effects are all reproducible and can be used for non-local signalling and many other purposes. We suggest that they are mediated by quantum entanglement between nuclear and/or electron spins in treated water and discuss the implications of these results.

  20. Effect of sun radiation on the thermal behavior of distribution transformer

    International Nuclear Information System (INIS)

    Hajidavalloo, Ebrahim; Mohamadianfard, Mohamad

    2010-01-01

    Performance and life of oil-immersed distribution transformers are strongly dependent on the oil temperature. Transformers, working in regions with high temperature and high solar radiation, usually suffer from excessive heat in summers which results in their early failures. In this paper, the effect of sun radiation on the transformer was investigated by using experimental and analytical methods. Transformer oil temperature was measured in two different modes, with and without sun shield. Effects of different parameters such as direct and indirect solar radiation on the thermal behavior of the transformer were mathematically modeled and the results were compared with experimental findings. Agreements between the experimental and numerical results show that the model can reasonably predict thermal behavior of the transformer. It was found that a sun shield has an important effect on the oil temperature reduction in summer which could be as high as 7 deg. C depending on the load ratio. The amount of temperature reduction by sun shield reduces as the load ratio of transformer increases. By installing a sun shield and reducing oil temperature, transformer life could be increased up to 24% in average.

  1. The effect of nozzle location on the concentration profiles in chemical addition tank

    International Nuclear Information System (INIS)

    Park, B. H.; Kim, E. K.; Ro, T. S.; Lee, C. H.

    2001-01-01

    A numerical analysis of the flow and injection characteristics is performed for the flow field created by water injected into a cylindrical tank with an initially stationary fluid. The flow is relevant to the operation of the chemical addition system in the chemical and volume control system( CVCS) of nuclear power plants. This study is performed to improve the current design which has a disk block inside tank. The numerical analysis for the flow and injection characteristics in chemical addition tank are carried out using CFD code FLUENT 5. Results show that the inlet nozzle installed in tangential direction at the uppermost region of the tank cylinder and the outlet nozzle located at the center of the tank bottom is very effective in enhancing the injection in the tank

  2. Low-frequency electromagnetic measurements as a zero-time discriminant of nuclear and chemical explosions - OSI research final report

    International Nuclear Information System (INIS)

    Sweeney, J.J.

    1996-12-01

    This is the final report on a series of investigations of low frequency (1-40 Hz) electromagnetic signals produced by above ground and underground chemical explosions and their use for confidence building under the Comprehensive Test-Ban Treaty. I conclude that low frequency electromagnetic measurements can be a very powerful tool for zero-time discrimination of chemical and nuclear explosions for yields of 1 Kt or greater, provided that sensors can be placed within 1-2 km of the suspected detonation point in a tamper-proof, low noise environment. The report includes descriptions and analyses of low frequency electromagnetic measurements associated with chemical explosions carried out in a variety of settings (shallow borehole, open pit mining, underground mining). I examine cavity pressure data from the Non-Proliferation Experiment (underground chemical explosion) and present the hypothesis that electromagnetic signals produced by underground chemical explosions could be produced during rock fracturing. I also review low frequency electromagnetic data from underground nuclear explosions acquired by Lawrence Livermore National Laboratory during the late 1980s. (author)

  3. Chemical characterization of materials relevant to nuclear technology using neutron and proton based nuclear analytical methods

    International Nuclear Information System (INIS)

    Acharya, R.

    2014-01-01

    Nuclear analytical techniques (NATs), utilizing neutron and proton based nuclear reactions and subsequent measurement of gamma rays, are capable of chemical characterization of various materials at major to trace concentration levels. The present article deals with the recent developments and applications of conventional and k0-based internal monostandard (i) neutron activation analysis (NAA) and (ii) prompt gamma ray NAA (PGNAA) methods as well as (iii) in situ current normalized particle induced gamma ray emission (PIGE). The materials that have been analyzed by NAA and PGNAA include (i) nuclear reactor structural materials like zircaloys, stainless steels, Ni alloys, high purity aluminium and graphite and (ii) uranium oxide, U-Th mixed oxides, uranium ores and minerals. Internal monostandard NAA (IM-NAA) method with in situ detection efficiency was used to analyze large and non-standard geometry samples and standard-less compositional characterization was carried out for zircaloys and stainless steels. PIGE methods using proton beams were standardized for quantification of low Z elements (Li to Ti) and applied for compositional analysis of borosilicate glass and lithium titanate (Li 2 TiO 3 ) samples and quantification of total B and its isotopic composition of B ( 10 B/ 11 B) in boron based neutron absorbers like B 4 C. (author)

  4. Reliability improvement of potential transformer and secondary circuit of 6 kV 1E-class buses in Qinshan nuclear power plant

    International Nuclear Information System (INIS)

    Qian Houjun

    2014-01-01

    There are design defects in potential transformer (PT) and secondary circuit of 6 kV 1E-class buses in Qinshan Nuclear Power Plant Nuclear Island. During the operating period, there happened several serious operational events (loss of power) caused by PT resonance. The essay analyses the defects of original design, and put forward corresponding modification measures, which have been carried out by two steps between 2009 and 2010, and after the modification the same problems have not happened again. (author)

  5. Study of phase transformation of U-2,5Zr-7,5Nb e U-3Zr-9Nb alloys for application in advanced nuclear fuel; Estudo das transformacoes de fases nas ligas U-2,5Zr-7,5Nb e U-3Zr-9Nb para aplicacao em combustivel nuclear avancado

    Energy Technology Data Exchange (ETDEWEB)

    Pais, Rafael Witter Dias

    2015-07-01

    Metal fuels are relevant in the nuclear area due to the versatility of its use in the nuclear fuel cycle. Among the alloys of uranium investigated with high potential for use in nuclear power reactors, U-Zr-Nb alloys appear as an important alternative because of their superior physico-chemical and metallurgical properties. These alloys have also potential for use in nuclear testing, research and production radioisotopes of high performance nuclear reactors. Therefore, the development of these alloys is strategic since they are planned to be used in national reactors as RMB (Brazilian Multipurpose Reactor) and LABGENE (Electrical Generation Core Laboratory), currently under development in Brazil. In this work it was realized a extensive study in the scope of the manufacturing, heat treatment and phase transformations of U-2,5Zr-7,5Nb (m/m%) and U-3ZR-9NB (m/m%) fuel alloys. Ingots of both alloys were produced employing a specific methodology developed in this study. This methodology comprised the melting process in a vacuum induction furnace at high temperatures (1500 °C) and thermal-mechanical processing to break the as-cast structure. Samples with typical dimensions (17 x 7 x 2.5 mm) free from macrostructural defects were homogenized at 1000 °C in vacuum of 10{sup -5} torr for 17.5 hours with a 10°C/min cooling rate until to 820 °C and, subsequently, quenched in water. The samples, randomly selected, were subjected to isothermal treatment tests under different conditions of time and temperature. Isothermal treatments for transformation and retention phases were carried out in a special assembly designed for this work. After the tests, the samples were characterized by the usual phase characterization techniques with particular emphasis for the X-ray diffraction technique. In this way, the Rietveld refinement method was applied. In the case of uranium based alloys it is quite challenging due to the lack of data in the literature. In this work a strategy for the

  6. From Streams to Lumps: Transforming Long-Term Incentives into Up-Front Financing for New Nuclear Construction

    International Nuclear Information System (INIS)

    George, Glenn R.

    2006-01-01

    The Energy Policy Act of 2005 is an important development in the financing of new nuclear capacity in the near- to mid-term in the U.S.A. Key features of the Act, including production tax credits, loan guarantees, funding support, and 'standby support', are intended to provide significant incentives for new nuclear development, construction, and operation. There is a mismatch, however, between the nature and extent of incentives being offered and what is needed to spur nuclear plant deployment in light of power market uncertainty, utility investor wariness, and the need to raise significant capital before a nuclear construction project can be launched. In this paper, the author addresses these issues through the lens of financial tools and techniques. The paper considers various ways in which long-term streams of subsidies can be transformed into up-front financing for new nuclear capacity. Securing and related financial structures are among the mechanisms considered for potentially bridging the temporal gap between flows of financial benefits conferred legislatively and lumps of capital required by developers and investors in advance of a construction program. (authors)

  7. The effects of solar-geomagnetically induced currents on electrical systems in nuclear power stations

    International Nuclear Information System (INIS)

    Subudhi, M.; Carroll, D.P.; Kasturi, S.

    1994-01-01

    This report presents the results of a study to evaluate the potential effects of geomagnetically induced currents (GICs) caused by the solar disturbances on the in-plant electrical distribution system and equipment in nuclear power stations. The plant-specific electrical distribution system for a typical nuclear plant is modeled using the ElectroMagnetic Transient Program (EMTP). The computer model simulates online equipment and loads from the station transformer in the switchyard of the power station to the safety-buses at 120 volts to which all electronic devices are connected for plant monitoring. The analytical model of the plant's electrical distribution system is studied to identify the transient effects caused by the half-cycle saturation of the station transformers due to GIC. This study provides results of the voltage harmonics levels that have been noted at various electrical buses inside the plant. The emergency circuits appear to be more susceptible to high harmonics due to the normally light load conditions. In addition to steady-state analysis, this model was further analyzed simulating various plant transient conditions (e.g., loss of load or large motor start-up) occurring during GIC events. Detail models of the plant's protective relaying system employed in bus transfer application were included in this model to study the effects of the harmonic distortion of the voltage input. Potential harmonic effects on the uniterruptable power system (UPS) are qualitatively discussed as well

  8. Transformation assay in Bhas 42 cells: a model using initiated cells to study mechanisms of carcinogenesis and predict carcinogenic potential of chemicals.

    Science.gov (United States)

    Sasaki, Kiyoshi; Umeda, Makoto; Sakai, Ayako; Yamazaki, Shojiro; Tanaka, Noriho

    2015-01-01

    Transformation assays using cultured cells have been applied to the study of carcinogenesis. Although various cell systems exist, few cell types such as BALB/c 3T3 subclones and Syrian hamster embryo cells have been used to study chemically induced two-stage carcinogenesis. Bhas 42 cells were established as a clone by the transfection with the v-Ha-ras gene into mouse BALB/c 3T3 A31-1-1 cells and their subsequent selection based on their sensitivity to 12-O-tetradecanoylphorbol-13-acetate. Using Bhas 42 cells, transformed foci were induced by the treatment with nongenotoxic carcinogens, most of which act as tumor promoters. Therefore, Bhas 42 cells were considered to be a model of initiated cells. Subsequently, not only nongenotoxic carcinogens but also genotoxic carcinogens, most of which act as tumor initiators, were found to induce transformed foci by the modification of the protocol. Furthermore, transformation of Bhas 42 cells was induced by the transfection with genes of oncogenic potential. We interpret this high sensitivity of Bhas 42 cells to various types of carcinogenic stimuli to be related to the multistage model of carcinogenesis, as the transfection of v-Ha-ras gene further advances the parental BALB/c 3T3 A31-1-1 cells toward higher transforming potential. Thus, we propose that Bhas 42 cells are a novel and sensitive cell line for the analysis of carcinogenesis and can be used for the detection of not only carcinogenic substances but also gene alterations related to oncogenesis. This review will address characteristics of Bhas 42 cells, the transformation assay protocol, validation studies, and the various chemicals tested in this assay.

  9. NUMATH: a nuclear-material-holdup estimator for unit operations and chemical processes

    International Nuclear Information System (INIS)

    Krichinsky, A.M.

    1981-01-01

    A computer program, NUMATH (Nuclear Material Holdup Estimator), has been developed to permit inventory estimation in vessels involved in unit operations and chemical processes. This program has been implemented in an operating nuclear fuel processing plant. NUMATH's purpose is to provide steady-state composition estimates for material residing in process vessels until representative samples can be obtained and chemical analyses can be performed. Since these compositions are used for inventory estimation, the results are determined for and cataloged in container-oriented files. The estimated compositions represent material collected in applicable vessels-including consideration for material previously acknowledged in these vessels. The program utilizes process measurements and simple material balance models to estimate material holdups and distribution within unit operations. During simulated run testing, NUMATH-estimated inventories typically produced material balances within 7% of the associated measured material balances for uranium and within 16% of the associated, measured material balance for thorium during steady-state process operation

  10. Pyrochlore as nuclear waste form. Actinide uptake and chemical stability

    International Nuclear Information System (INIS)

    Finkeldei, Sarah Charlotte

    2015-01-01

    Radioactive waste is generated by many different technical and scientific applications. For the past decades, different waste disposal strategies have been considered. Several questions on the waste disposal strategy remain unanswered, particularly regarding the long-term radiotoxicity of minor actinides (Am, Cm, Np), plutonium and uranium. These radionuclides mainly arise from high level nuclear waste (HLW), specific waste streams or dismantled nuclear weapons. Although many countries have opted for the direct disposal of spent fuel, from a scientific and technical point of view it is imperative to pursue alternative waste management strategies. Apart from the vitrification, especially for trivalent actinides and Pu, crystalline ceramic waste forms are considered. In contrast to glasses, crystalline waste forms, which are chemically and physically highly stable, allow the retention of radionuclides on well-defined lattice positions within the crystal structure. Besides polyphase ceramics such as SYNROC, single phase ceramics are considered as tailor made host phases to embed a specific radionuclide or a specific group. Among oxidic single phase ceramics pyrochlores are known to have a high potential for this application. This work examines ZrO 2 based pyrochlores as potential nuclear waste forms, which are known to show a high aqueous stability and a high tolerance towards radiation damage. This work contributes to (1) understand the phase stability field of pyrochlore and consequences of non-stoichiometry which leads to pyrochlores with mixed cationic sites. Mixed cationic occupancies are likely to occur in actinide-bearing pyrochlores. (2) The structural uptake of radionuclides themselves was studied. (3) The chemical stability and the effect of phase transition from pyrochlore to defect fluorite were probed. This phase transition is important, as it is the result of radiation damage in ZrO 2 based pyrochlores. ZrO 2 - Nd 2 O 3 pellets with pyrochlore and defect

  11. Psychological effects of nuclear warfare

    International Nuclear Information System (INIS)

    Mickley, G.A.

    1987-01-01

    This report is divided into five parts. (1) Discussion of the psychological milieu before a nuclear confrontation. (2) Acute psychological reactions to nuclear warfare (some of which may reflect, in part, direct radiogenic alteration of nervous system functions). (3) Chronic psychological effects of a nuclear confrontation. (4) Issues concerning treatment of these psychological changes. (5) Prevention of adverse psychological reactions to nuclear warfare

  12. Aging study on carboxymethyl cellulose-coated zero-valent iron nanoparticles in water: Chemical transformation and structural evolution

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Haoran, E-mail: dongh@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082 (China); Zhao, Feng; Zeng, Guangming; Tang, Lin; Fan, Changzheng; Zhang, Lihua; Zeng, Yalan; He, Qi; Xie, Yankai; Wu, Yanan [College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082 (China)

    2016-07-15

    Highlights: • The chemical transformation and structural evolution of CMC-nZVI were investigated. • CMC could slow down the aging rate of nZVI and alter the species transformation. • Fe{sub 3}O{sub 4} and/or γ-Fe{sub 2}O{sub 3} are the dominant corrosion products of bare nZVI after aging. • γ-FeOOH is the primary corrosion product of CMC-nZVI after aging. - Abstract: To assess the long-term fate and the associated risks of nanoscale zero-valent iron (nZVI) used in the water remediation, it is essential to understand the chemical transformations during aging of nZVI in water. This study investigated the compositional and structural evolution of bare nZVI and carboxymethyl cellulose (CMC) coated nZVI in static water over a period of 90 days. Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy were used to characterize the corrosion products of nZVI and CMC-nZVI. Results show that both the structures and the compositions of the corrosion products change with the process of aging, but the coating of CMC could slow down the aging rate of nZVI (as indicated by the slower drop in Fe{sup 0} intensity in XRD pattern). For the bare nZVI, magnetite (Fe{sub 3}O{sub 4}) and/or maghemite (γ-Fe{sub 2}O{sub 3}) are the dominant corrosion products after 90 days of aging. However, for the CMC-nZVI, the core-shell spheres collapses to acicular-shaped structures after aging with crystalline lepidocrocite (γ-FeOOH) as the primary end product. Moreover, more lepidocrocite present in the corrosion products of CMC-nZVI with higher loading of CMC, which reveals that the CMC coating could influence the transformation of iron oxides.

  13. Aging study on carboxymethyl cellulose-coated zero-valent iron nanoparticles in water: Chemical transformation and structural evolution

    International Nuclear Information System (INIS)

    Dong, Haoran; Zhao, Feng; Zeng, Guangming; Tang, Lin; Fan, Changzheng; Zhang, Lihua; Zeng, Yalan; He, Qi; Xie, Yankai; Wu, Yanan

    2016-01-01

    Highlights: • The chemical transformation and structural evolution of CMC-nZVI were investigated. • CMC could slow down the aging rate of nZVI and alter the species transformation. • Fe_3O_4 and/or γ-Fe_2O_3 are the dominant corrosion products of bare nZVI after aging. • γ-FeOOH is the primary corrosion product of CMC-nZVI after aging. - Abstract: To assess the long-term fate and the associated risks of nanoscale zero-valent iron (nZVI) used in the water remediation, it is essential to understand the chemical transformations during aging of nZVI in water. This study investigated the compositional and structural evolution of bare nZVI and carboxymethyl cellulose (CMC) coated nZVI in static water over a period of 90 days. Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy were used to characterize the corrosion products of nZVI and CMC-nZVI. Results show that both the structures and the compositions of the corrosion products change with the process of aging, but the coating of CMC could slow down the aging rate of nZVI (as indicated by the slower drop in Fe"0 intensity in XRD pattern). For the bare nZVI, magnetite (Fe_3O_4) and/or maghemite (γ-Fe_2O_3) are the dominant corrosion products after 90 days of aging. However, for the CMC-nZVI, the core-shell spheres collapses to acicular-shaped structures after aging with crystalline lepidocrocite (γ-FeOOH) as the primary end product. Moreover, more lepidocrocite present in the corrosion products of CMC-nZVI with higher loading of CMC, which reveals that the CMC coating could influence the transformation of iron oxides.

  14. Improving nuclear regulatory effectiveness

    International Nuclear Information System (INIS)

    2001-01-01

    Ensuring that nuclear installations are operated and maintained in such a way that their impact on public health and safety is as low as reasonably practicable has been and will continue to be the cornerstone of nuclear regulation. In the past, nuclear incidents provided the main impetus for regulatory change. Today, economic factors, deregulation, technological advancements, government oversight and the general requirements for openness and accountability are leading regulatory bodies to review their effectiveness. In addition, seeking to enhance the present level of nuclear safety by continuously improving the effectiveness of regulatory bodies is seen as one of the ways to strengthen public confidence in the regulatory systems. This report covers the basic concepts underlying nuclear regulatory effectiveness, advances being made and future requirements. The intended audience is primarily nuclear safety regulators, but government authorities, nuclear power plant operators and the general public may also be interested. (author)

  15. Thyroid effects of endocrine disrupting chemicals.

    Science.gov (United States)

    Boas, Malene; Feldt-Rasmussen, Ulla; Main, Katharina M

    2012-05-22

    In recent years, many studies of thyroid-disrupting effects of environmental chemicals have been published. Of special concern is the exposure of pregnant women and infants, as thyroid disruption of the developing organism may have deleterious effects on neurological outcome. Chemicals may exert thyroid effects through a variety of mechanisms of action, and some animal experiments and in vitro studies have focused on elucidating the mode of action of specific chemical compounds. Long-term human studies on effects of environmental chemicals on thyroid related outcomes such as growth and development are still lacking. The human exposure scenario with life long exposure to a vast mixture of chemicals in low doses and the large physiological variation in thyroid hormone levels between individuals render human studies very difficult. However, there is now reasonably firm evidence that PCBs have thyroid-disrupting effects, and there is emerging evidence that also phthalates, bisphenol A, brominated flame retardants and perfluorinated chemicals may have thyroid disrupting properties. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. Chemical cleaning for sludge in steam generator of nuclear power plant

    International Nuclear Information System (INIS)

    Zhang Mengqin; Lu Yucheng; Zhang Binyong; Yu Jinghua

    2002-01-01

    The sludge induced corrosion damage to secondary side of tubes of Steam Generator (SG), effect of chemical cleaning technique on maintenance integrity of tubes of SG NPP and use of chemical cleaning technique in SG NPP have been summarized. The engineering technique of chemical cleaning for removing sludge in secondary side of SG NPP has been studied and qualified by CIAE (China Institute of Atomic Energy). Chemical cleaning engineering technique is introduced (main agent is EDTA, temp. <100 degree C), including chemical cleaning technology for tube plate and full tube nest of secondary side of SG, the monitoring technique of chemical cleaning process (effectiveness and safety), the disposal method of wastage of chemical cleaning, the system of chemical cleaning. The method for preventing sludge deposition in secondary side and the research on advanced water chemistry of secondary loop are introduced

  17. Effectiveness of Discovery Learning-Based Transformation Geometry Module

    Science.gov (United States)

    Febriana, R.; Haryono, Y.; Yusri, R.

    2017-09-01

    Development of transformation geometry module is conducted because the students got difficulties to understand the existing book. The purpose of the research was to find out the effectiveness of discovery learning-based transformation geometry module toward student’s activity. Model of the development was Plomp model consisting preliminary research, prototyping phase and assessment phase. The research was focused on assessment phase where it was to observe the designed product effectiveness. The instrument was observation sheet. The observed activities were visual activities, oral activities, listening activities, mental activities, emotional activities and motor activities. Based on the result of the research, it is found that visual activities, learning activities, writing activities, the student’s activity is in the criteria very effective. It can be concluded that the use of discovery learning-based transformation geometry module use can increase the positive student’s activity and decrease the negative activity.

  18. Inventory of chemical releases of nuclear installations in the North-Cotentin; Inventaire des rejets chimiques des installations nucleaires du Nord-Cotentin

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-05-15

    The nuclear installations concerned by this study are Cogema La Hague, the Flamanville nuclear power plant, the Manche plant and the National Navy of Cherbourg.The objective followed by the ' source term ' work group has consisted in counting and examining the whole of existing measures relative to the releases of chemical substances in the liquid and gaseous effluents. Then because of the lack of measures for the operation first years of installations, the work group has estimated the order of magnitude of these chemical releases (essentially for Cogema La Hague). This report presents a review of the literature looking at the background levels of chemicals in different environmental compartments: air, soil, plants and animals products. these values have been summarized here to be available for comparisons with concentrations input by the North Cotentin nuclear installations, calculated by the G.R.N.C. (radioecology group of Nord Cotentin)

  19. Study relating to the physico-chemical behaviour of heavy water in nuclear reactors

    International Nuclear Information System (INIS)

    Chenouard, J.; Dirian, G.; Roth, E.; Vignet, P.; Platzer, R.

    1959-01-01

    Chemical and isotope pollution, and radiolytic decomposition are the two most important ways in which heavy water becomes degraded in nuclear reactors. Chemical pollution has led to the creation of ion exchange purification loops specially designed for reactors: the report contains a description in detail of the application of this purification method in CEA research reactors, including the analysis required, results obtained, and their interpretation. The intelligence obtained on radiolytic decomposition with the same facilities is also discussed, as well as the recombination apparatus and control equipment utilized. Finally, investigation to date in the CEA on recombination circuits for power reactors is also discussed. (author) [fr

  20. ARTIST process. A novel chemical process for treatment of spent nuclear fuel

    International Nuclear Information System (INIS)

    Tachimori, Shoichi

    2001-10-01

    A new chemical process, ARTIST process, is proposed for the treatment of spent nuclear fuel. The main concept of the ARTIST process is to recover and stock all actinides (Ans) as two groups, uranium (U) and a mixture of transuranics (TRU), to preserve their resource value and to dispose solely fission products (FPs). The process is composed of two main steps, an U exclusive isolation and a total recovery of TRU; which copes with the nuclear non-proliferation measures, and additionally of Pu separation process and soft N-donor process if requested, and optionally of processes for separation of long-lived FPs. These An products: U-product and TRU-product, are to be solidified by calcination and allowed to the interim stockpile for future utilization. These separations are achieved by use of amidic extractants in accord with the CHON principle. The technical feasibility of the ARTIST process was explained by the performance of both the branched alkyl monoamides in extracting U and suppressing the extraction of tetravalent Ans due to the steric effect and the diglycolic amide (TODGA) in thorough extraction of all TRU by tridentate fashion. When these TRU are requested to put into reactors, LWR or FBR, for power generation or the Accelerator - Driven System (ADS) for transmutation, Pu (Np) or Am-Cm (Np) are to be extracted from the TRU-product. (author)

  1. A study on domino effect in nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    Bozzolan, Jean-Claude

    2006-01-01

    Accidents caused by domino effect are among the most severe accidents in the chemical and process industry. Although the destructive potential of these accidental scenarios is widely known, little attention has been paid to this problem in the technical literature and a complete methodology for quantitative assessment of domino accidents contribution to industrial risk is still lacking. The present study proposed a systematic procedure for the quantitative assessment of the risk caused by domino effect in chemical plants that are part of nuclear fuel cycle plants. This work is based on recent advances in the modeling of fire and explosion damage to process equipment due to different escalation vectors (heat radiation, overpressure and fragment projection). Available data from literature and specific vulnerability models derived for several categories of process equipment had been used in the present work. The proposed procedure is applied to a typical storage area of a reconversion plant situated in a complex that shelters other nuclear fuel cycle facilities. The top-events and escalation vectors are identified, their consequences estimated and credible domino scenarios selected on the basis of their frequencies. (author)

  2. The terrorist threat nuclear, radiological, biological, chemical - a medical approach; Menace terroriste nucleaire, radiologique, biologique, chimique - approche medicale

    Energy Technology Data Exchange (ETDEWEB)

    Revel, M.C. de; Gourmelon, M.C.S.; Vidal, P.C.; Renaudeau, P.C.S

    2005-07-01

    Since September 11, 2001, the fear of a large scale nuclear, biological and/or chemical terrorism is taken again into consideration at the highest level of national policies of risk prevention. The advent of international terrorism implies a cooperation between the military defense and the civil defense. The nuclear, radiological, biological and chemical (NRBC) experts of the health service of army and of civil defense will have to work together in case of major terror attack. This book presents this cooperation between civil and military experts in the NRBC domain: risk analysis, national defense plans, crisis management, syndromes and treatments. The different aspects linked with the use of nuclear, biological and chemical weapons are analyzed by the best experts from French medical and research institutes. All topics of each NRBC domain are approached: historical, basic, diagnostic, therapeutic and preventive. (J.S.)

  3. The Effects of Nuclear Weapons. Third edition

    Energy Technology Data Exchange (ETDEWEB)

    Glasstone, S; Dolan, P J

    1977-01-01

    Since the last edition of ''The Effects of Nuclear Weapons'' in 1962 much new information has become available concerning nuclear weapon effects. This has come in part from the series of atmospheric tests, including several at very high altitudes, conducted in the Pacific Ocean area in 1962. In addition, laboratory studies, theoretical calculations, and computer simulations have provided a better understanding of the various effects. A new chapter has been added on the electromagnetic pulse. The chapter titles are as follows: general principles of nuclear explosions; descriptions of nuclear explosions; air blast phenomena in air and surface bursts; air blast loading; structural damage from air blast; shock effects of surface and subsurface bursts; thermal radiation and its effects; initial nuclear radiation; residual nuclear radiation and fallout; radio and radar effects; the electromagnetic pulse and its effects; and biological effects. (LTN)

  4. Thyroid effects of endocrine disrupting chemicals

    DEFF Research Database (Denmark)

    Boas, Malene; Feldt-Rasmussen, Ulla; Main, Katharina M

    2012-01-01

    In recent years, many studies of thyroid-disrupting effects of environmental chemicals have been published. Of special concern is the exposure of pregnant women and infants, as thyroid disruption of the developing organism may have deleterious effects on neurological outcome. Chemicals may exert ...... thyroid-disrupting effects, and there is emerging evidence that also phthalates, bisphenol A, brominated flame retardants and perfluorinated chemicals may have thyroid disrupting properties....

  5. Chemical, biological, radiological, and nuclear decontamination: Recent trends and future perspective

    Directory of Open Access Journals (Sweden)

    Vinod Kumar

    2010-01-01

    Full Text Available Chemical, biological, radiological, and nuclear (CBRN decontamination is the removal of CBRN material from equipment or humans. The objective of the decontamination is to reduce radiation burden, salvage equipment, and materials, remove loose CBRN contaminants, and fix the remaining in place in preparation for protective storage or permanent disposal work activities. Decontamination may be carried out using chemical, electrochemical, and mechanical means. Like materials, humans may also be contaminated with CBRN contamination. Changes in cellular function can occur at lower radiation doses and exposure to chemicals. At high dose, cell death may take place. Therefore, decontamination of humans at the time of emergency while generating bare minimum waste is an enormous task requiring dedication of large number of personnel and large amount of time. General principles of CBRN decontamination are discussed in this review with emphasis on radiodecontamination.

  6. Effect of the Fukushima nuclear disaster on global public acceptance of nuclear energy

    International Nuclear Information System (INIS)

    Kim, Younghwan; Kim, Minki; Kim, Wonjoon

    2013-01-01

    The Fukushima nuclear disaster has significantly changed public attitudes toward nuclear energy. It is important to understand how this change has occurred in different countries before the global community revises existing nuclear policies. This study examines the effect of the Fukushima disaster on public acceptance of nuclear energy in 42 countries. We find that the operational experience of nuclear power generation which has significantly affected positive public opinion about nuclear energy became considerably negative after the disaster, suggesting fundamental changes in public acceptance regardless of the level of acceptance before the disaster. In addition, contrary to our expectation, the proportion of nuclear power generation is positively and significantly related to public acceptance of nuclear energy after the Fukushima accident and government pressure on media content led to a greater decrease in the level of public acceptance after the accident. Nuclear energy policymakers should consider the varied factors affecting public acceptance of nuclear energy in each country depending on its historical, environmental, and geographical circumstances before they revise nuclear policy in response to the Fukushima accident. - Highlights: • Fukushima accident has negatively changed public attitudes toward nuclear energy. • Effect of operational experience became considerably negative after the accident. • Effect of proportion of nuclear power generation is positive after the accident. • Effect of government pressure on media content became negative after the accident. • Country specific policy responses on nuclear public acceptance are required

  7. Biological effects of radiation: The induction of malignant transformation and programmed cell death

    International Nuclear Information System (INIS)

    Servomaa, K.

    1991-04-01

    In the Chernobyl explosions and fire, powderized nuclear fuel was released from the reactor core, causing an unexpected fallout. X-ray analysis and scanning electron microscopy showed that the isolated single particles were essentially pure uranium. These uranium aerosols contained all of the nonvolatile fission products, including the b-emitters, 95 Zr, 103 Ru, 106 Ru, 141 Ce, and 144 Ce. The hot particles are extremely effective in inducing malignant transformation in mouse fibroblast cells in vitro. The major factor responsible for this effect is focus promotion caused by a wound-mediated permanent increase in cell proliferation (mitogenesis associated with mutagenesis). Transformed foci were analysed for the activation of c-abl, c-erb-A, c-erb-B, c-fms, c-fos, c-myb, c-myc, c-Ha-ras, c-Ki-ras, c-sis, and c-raf oncogenes at the transcriptional level. The pattern of oncogene activation was found to vary from focus to focus. Long interspersed repeated DNA (L1 or LINE makes up a class of mobile genetic elements which can amplify in the cell genome by retroposition. This element is spontaneously transcriptionally activated at a critical population density and later amplified in rat chloroleukaemia cells. UV light and ionizing radiation induce this activation prematurely, and the activation is followed by programmed cell death (apoptosis) in a sequence of events identical to that seen in LIRn activation occurring spontaneously

  8. Simulation of the chemical environment of a nuclear explosion with exploding wires

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Walter; Block, Oliver U.J. [Nuclear Engineering, Kansas State University, Manhattan, KS (United States)

    1970-05-15

    The chemical processes in an expanding underground cavity resulting from a nuclear explosion cannot be predicted or controlled as well as such physical characteristics as crater size, magnitude of the outgoing shock wave, or the extent of rock fracturing. However in most underground nuclear explosions it would be desirable to control the chemical and/or physical form and amount of radioactive fallout venting from the explosion. The high temperatures and corresponding high energy densities produced by exploding wires are sufficient to produce in the wire and material immediately surrounding it the temperature (a few thousand degrees) required to simulate the chemical environment of a nuclear explosion in the time interval just preceding the venting of the cavity. The economics and the size of exploding wire apparatus make this type of experiment readily applicable to laboratory study. Design of exploding wire circuits to obtain particular temperatures or energy densities can be completed using several different combinations of circuit and wire conditions. Since the circuit parameters, including charging voltage, capacitor bank capacitance and circuit inductance primarily determine the cost of the necessary laboratory equipment, these parameters should be selected by theoretical expressions while also considering economic factors. Wire parameters are then experimentally determined to produce the most energetic explosions with the selected circuit parameters. A theoretical method applicable to designing exploding wire circuits to produce the desired high temperatures and energy densities in the wire and surrounding sample material has been obtained. The method assumes that a thermal spike of energy is deposited in a low conductivity material (typical of the earth's crust) surrounding the wire. From the assumed temperature distribution in the surrounding sample material the energy which must be deposited in the thermal spike to produce the desired temperature and

  9. Effects of 17 beta-estradiol on radiation transformation in vitro; inhibition of effects by protease inhibitors

    International Nuclear Information System (INIS)

    Kennedy, A.R.; Weichselbaum, R.R.

    1981-01-01

    We have investigated the effects of 17 beta-estradiol, given both alone and with X-irradiation, on the induction of malignant transformation in vitro. Treatment with 10(-6)M 17 beta-estradiol for 6 weeks, or 10(-5)M 17 beta-estradiol for only 5 days, induced malignant transformation in C3H 10T1/2 cells. Estradiol also acted as a cocarcinogen for X-ray induced transformation; the results indicate an additive effect when the cells were exposed to both agents together. The protease inhibitors antipain and leupeptin suppressed estradiol induced transformation as well as the additive effect observed for estradiol-radiation transformation

  10. Effects of 17β-estradiol on radiation transformation in vitro; inhibition of effects by protease inhibitors

    International Nuclear Information System (INIS)

    Kennedy, A.R.; Weichselbaum, R.R.

    1981-01-01

    The effects of 17β-estradiol, given either alone or with X-radiation, on the induction of malignant transformation were investigated in vitro. Treatment with 10 -6 M 17β-estradiol for 6 weeks, or 10 -5 M 17β-estradiol for only 5 days, induced malignant transformation in C3H 10T1/2 cells. Estradiol also acted as a cocarcinogen for X-ray induced transformation; the results indicated an additive effect when the cells were exposed to both agents together. The protease inhibitors antipain and leupeptin suppressed estradiol induced transformation as well as the additive effect observed for estradiol-radiation transformation. (author)

  11. Effects of 17 beta-estradiol on radiation transformation in vitro; inhibition of effects by protease inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, A.R.; Weichselbaum, R.R.

    1981-01-01

    We have investigated the effects of 17 beta-estradiol, given both alone and with X-irradiation, on the induction of malignant transformation in vitro. Treatment with 10(-6)M 17 beta-estradiol for 6 weeks, or 10(-5)M 17 beta-estradiol for only 5 days, induced malignant transformation in C3H 10T1/2 cells. Estradiol also acted as a cocarcinogen for X-ray induced transformation; the results indicate an additive effect when the cells were exposed to both agents together. The protease inhibitors antipain and leupeptin suppressed estradiol induced transformation as well as the additive effect observed for estradiol-radiation transformation.

  12. Effects of chemical form of sodium on the product characteristics of alkali lignin pyrolysis.

    Science.gov (United States)

    Guo, Da-liang; Yuan, Hong-you; Yin, Xiu-li; Wu, Chuang-zhi; Wu, Shu-bin; Zhou, Zhao-qiu

    2014-01-01

    The effects of Na as organic bound form or as inorganic salts form on the pyrolysis products characteristics of alkali lignin were investigated by using thermogravimetric analyzer coupled with Fourier transform infrared spectrometry (TG-FTIR), tube furnace and thermo-gravimetric analyzer (TGA). Results of TG-FTIR and tube furnace indicated that the two chemical forms Na reduced the releasing peak temperature of CO and phenols leading to the peak temperature of the maximum mass loss rate shifted to low temperature zone. Furthermore, organic bound Na obviously improved the elimination of alkyl substituent leading to the yields of phenol and guaiacol increased, while inorganic Na increased the elimination of phenolic hydroxyl groups promoting the formation of ethers. It was also found the two chemical forms Na had different effects on the gasification reactivity of chars. For inorganic Na, the char conversion decreased with increasing the char forming temperature, while organic bound Na was opposite. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  13. Nuclear analytical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Brune, D.; Forkman, B.; Persson, B.

    1984-01-01

    This book covers the general theories and techniques of nuclear chemical analysis, directed at applications in analytical chemistry, nuclear medicine, radiophysics, agriculture, environmental sciences, geological exploration, industrial process control, etc. The main principles of nuclear physics and nuclear detection on which the analysis is based are briefly outlined. An attempt is made to emphasise the fundamentals of activation analysis, detection and activation methods, as well as their applications. The book provides guidance in analytical chemistry, agriculture, environmental and biomedical sciences, etc. The contents include: the nuclear periodic system; nuclear decay; nuclear reactions; nuclear radiation sources; interaction of radiation with matter; principles of radiation detectors; nuclear electronics; statistical methods and spectral analysis; methods of radiation detection; neutron activation analysis; charged particle activation analysis; photon activation analysis; sample preparation and chemical separation; nuclear chemical analysis in biological and medical research; the use of nuclear chemical analysis in the field of criminology; nuclear chemical analysis in environmental sciences, geology and mineral exploration; and radiation protection.

  14. Nuclear analytical chemistry

    International Nuclear Information System (INIS)

    Brune, D.; Forkman, B.; Persson, B.

    1984-01-01

    This book covers the general theories and techniques of nuclear chemical analysis, directed at applications in analytical chemistry, nuclear medicine, radiophysics, agriculture, environmental sciences, geological exploration, industrial process control, etc. The main principles of nuclear physics and nuclear detection on which the analysis is based are briefly outlined. An attempt is made to emphasise the fundamentals of activation analysis, detection and activation methods, as well as their applications. The book provides guidance in analytical chemistry, agriculture, environmental and biomedical sciences, etc. The contents include: the nuclear periodic system; nuclear decay; nuclear reactions; nuclear radiation sources; interaction of radiation with matter; principles of radiation detectors; nuclear electronics; statistical methods and spectral analysis; methods of radiation detection; neutron activation analysis; charged particle activation analysis; photon activation analysis; sample preparation and chemical separation; nuclear chemical analysis in biological and medical research; the use of nuclear chemical analysis in the field of criminology; nuclear chemical analysis in environmental sciences, geology and mineral exploration; and radiation protection

  15. Limits of transforming competence of SV40 nuclear and cytoplasmic large T mutants with altered Rb binding sequences.

    Science.gov (United States)

    Tedesco, D; Fischer-Fantuzzi, L; Vesco, C

    1993-03-01

    Multiple amino acid substitutions were introduced into the SV40 large T region that harbors the retinoblastoma protein (Rb) binding site and the nuclear transport signal, changing either one or both of these determinants. Mutant activities were examined in a set of assays allowing different levels of transforming potential to be distinguished; phenotypic changes in established and pre-crisis rat embryo fibroblasts (REFs) were detected under isogenic cell conditions, and comparisons made with other established rodent cells. The limit of the transforming ability of mutants with important substitutions in the Rb binding site fell between two transformation levels of the same established rat cells. Such cells could be induced to form dense foci but not agar colonies (their parental pre-crises REFs, as expected, were untransformed either way). Nonetheless, agar colony induction was possible in other cell lines, such as mouse NIH3T3 and (for one of the mutants) rat F2408. All these mutants efficiently immortalized pre-crisis REFs. The transforming ability of cytoplasmic mutants appeared to depend on the integrity of the Rb-binding sequence to approximately the same extent as that of the wild-type large T, although evidence of in vivo Rb-cytoplasmic large T complexes was not found. The presence or absence of small t was critical when the transforming task of mutants was near the limit of their abilities.

  16. Composition models for the viscosity and chemical durability of West Valley related nuclear waste glasses

    International Nuclear Information System (INIS)

    Feng, X.; Saad, E.E.; Freeborn, W.P.; Macedo, P.B.; Pegg, I.L.; Sassoon, R.E.; Barkatt, A.; Finger, S.M.

    1988-01-01

    There are two important criteria that must be satisfied by a nuclear waste glass durability and processability. The chemical composition of the glass must be such that it does not dissolve or erode appreciably faster than the decay of the radioactive materials embedded in it. The second criterion, processability, means that the glass must melt with ease, must be easily pourable, and must not crystallize appreciably. This paper summarizes the development of simple models for predicting the durability and viscosity of nuclear waste glasses from their composition

  17. The Unsuspected Roles of Chemistry in Nuclear Power Plants: Special Chemical Technologies for Enhanced Safety and Increased Performance

    International Nuclear Information System (INIS)

    Sempere Belda, Luis

    2008-01-01

    The plant's chemists main responsibility is the establishment and monitoring of an adequate water chemistry to minimize corrosion and in PWRs, to control the neutron flux. But this is by no means the only way in which chemical applications contribute to the performance and safety of a NPP during its entire life: The use of special coatings and treatment protects the plant's components from aggressive environmental conditions. The chemical scale removal in steam generators improves the power output of aging plants, helping even to achieve permissions for NPP life extension. The use of special adhesives can replace welding in complicated or high-dose areas, even underwater. And chemical decontamination is used to remove activity from the components of the primary circuit prior to maintenance or replacement works in order to decrease the radiation exposure of the plant's personnel, employing revolutionary methods of waste minimization to limit the amount of generated radioactive waste to a minimum. The AREVA Group, in its pursue of excellence in all stages of the nuclear cycle, has devoted years of research and development to be able to provide the most advanced technological solutions in this field. The awareness of the existing possibilities will help present and future nuclear professionals, chemists and non-chemists alike, to benefit from the years of experience and continuous development in chemical technologies at the service of the nuclear industry. (authors)

  18. Energy Transformation of Croatia

    International Nuclear Information System (INIS)

    Potocnik, V.

    2014-01-01

    Due to obvious climate change, caused mainly by combustion of the fossil fuels, as well as to their modest reserves, energy transformation is under way. It is the transition from the fossil fuels to improved energy efficiency (ENEF) and renewable energy sources (RES). Leading role in the energy transformation has Germany with 'Energiewende', which among other includes closing of existing nuclear power plants until 2022. Croatia has very limited proven fossil fuels reserves, which cover 3/4 of primary energy in consumption. Croatia also has large potential for improvements in ENEF and RES. Therefore, energy transformation of Croatia is justified. (author).

  19. Project research on nuclear physical and chemical characteristics of actinide nuclides

    International Nuclear Information System (INIS)

    Yamana, Hajimu; Nakagome, Yoshihiro; Shibata, Seiichi; Fujii, Toshiyuki; Uehara, Akihiro; Shirai, Osamu; Moriyama, Hirotake; Nagai, Takayuki; Yamanaka, Shinsuke; Shinohara, Atsushi; Kurata, Masaki; Myochin, Munetaka; Nakamura, Shoji; Matsuura, Haruaki

    2008-01-01

    The chemical and nuclear physical characteristics of actinide elements have been investigated using the experimental methods and instruments of this laboratory. This laboratory has a facility in which the transuranium elements (TRU) and the long-lived fission products (LLFP) can be dealt with. The utility of this facility has been expected. The investigation on the actinide elements and its fission products have been carried out as a project research from both view points of science and technology. The research reports during three years (2005-07) are described here. (M.H.)

  20. Biological effects of nuclear weapons

    International Nuclear Information System (INIS)

    Frischauf, H.

    1983-01-01

    Prompt and delayed biological effects of nuclear weapons are discussed. The response to excess pressure on man is estimated, the acute radiation syndrome caused by different radiation doses and cancerogenous and genetic effects are described. Medical care after a nuclear explosion would be difficult and imperfect. (M.J.)

  1. Chemically induced aneuploidy in mammalian cells: mechanisms and biological significance in cancer

    Energy Technology Data Exchange (ETDEWEB)

    Oshimura, M.; Barrett, J.C.

    1986-01-01

    A literature review with over 200 references examines the growing body of evidence from human and animal cancer cytogenetics that aneuploidy is an important chromosome change in carcinogenesis. Evidence from in vitro cell transformation studies supports the idea that aneuploidy has a direct effect on the conversion of a normal cell to a preneoplastic or malignant cell. Induction of an aneuploid state in a preneoplastic or neoplastic cell could have any of the following four biological effects: a change in gene dosage, a change in gene balance, expression of a recessive mutation, or a change in genetic instability (which could secondarily lead to neoplasia). There are a number of possible mechanisms by which chemicals might induce aneuploidy, including effects on microtubules, damage to essential elements for chromosome function reduction in chromosome condensation or pairing, induction of chromosome interchanges, unresolved recombination structures, increased chromosome stickiness, damage to centrioles, impairment of chromosome alignment ionic alterations during mitosis, damage to the nuclear membrane, and a physical disruption of chromosome segregation. Therefore, a number of different targets exist for chemically induced aneuploidy.

  2. UV-irradiation effects on polyester nuclear track detector

    International Nuclear Information System (INIS)

    Agarwal, Chhavi; Kalsi, P.C.

    2010-01-01

    The effects of UV irradiation (λ=254 nm) on polyester nuclear track detector have been investigated employing bulk-etch technique, UV-visible spectrophotometry and infra-red spectrometry (FTIR). The activation energy values for bulk-etching were found to decrease with the UV-irradiation time indicating the scission of the polymer. Not much shift in the absorption edge due to UV irradiation was seen in the UV-visible spectra. FTIR studies also indicate the scission of the chemical bonds, thereby further validating the bulk-etch rate results.

  3. Thermodynamic analysis of the use a chemical heat pump to link a supercritical water-cooled nuclear reactor and a thermochemical water-splitting cycle for hydrogen production

    International Nuclear Information System (INIS)

    Granovskii, Mikhail; Dincer, Ibrahim; Rosen, Marc A.; Pioro, Igor

    2008-01-01

    Increases in the power generation efficiency of nuclear power plants (NPPs) are mainly limited by the permissible temperatures in nuclear reactors and the corresponding temperatures and pressures of the coolants in reactors. Coolant parameters are limited by the corrosion rates of materials and nuclear-reactor safety constraints. The advanced construction materials for the next generation of CANDU reactors, which employ supercritical water (SCW) as a coolant and heat carrier, permit improved 'steam' parameters (outlet temperatures up to 625degC and pressures of about 25 MPa). An increase in the temperature of steam allows it to be utilized in thermochemical water splitting cycles to produce hydrogen. These methods are considered by many to be among the most efficient ways to produce hydrogen from water and to have advantages over traditional low-temperature water electrolysis. However, even lower temperature water splitting cycles (Cu-Cl, UT-3, etc.) require an intensive heat supply at temperatures higher than 550-600degC. A sufficient increase in the heat transfer from the nuclear reactor to a thermochemical water splitting cycle, without jeopardizing nuclear reactor safety, might be effectively achieved by application of a heat pump, which increases the temperature of the heat supplied by virtue of a cyclic process driven by mechanical or electrical work. Here, a high-temperature chemical heat pump, which employs the reversible catalytic methane conversion reaction, is proposed. The reaction shift from exothermic to endothermic and back is achieved by a change of the steam concentration in the reaction mixture. This heat pump, coupled with the second steam cycle of a SCW nuclear power generation plant on one side and a thermochemical water splitting cycle on the other, increases the temperature of the 'nuclear' heat and, consequently, the intensity of heat transfer into the water splitting cycle. A comparative preliminary thermodynamic analysis is conducted of

  4. Chemical and physical transformations of organic aerosol from the photo-oxidation of open biomass burning emissions in an environmental chamber

    Science.gov (United States)

    C. J. Hennigan; M. A. Miracolo; G. J. Engelhart; A. A. May; A. A. Presto; T. Lee; A. P. Sullivan; G. R. McMeeking; H. Coe; C. E. Wold; W.-M. Hao; J. B. Gilman; W. C. Kuster; J. de Gouw; B. A. Schichtel; J. L. Collett; S. M. Kreidenweis; A. L. Robinson

    2011-01-01

    Smog chamber experiments were conducted to investigate the chemical and physical transformations of organic aerosol (OA) during photo-oxidation of open biomass burning emissions. The experiments were carried out at the US Forest Service Fire Science Laboratory as part of the third Fire Lab at Missoula Experiment (FLAME III). We investigated emissions from 12 different...

  5. Transformation of correlation coefficients between normal and lognormal distribution and implications for nuclear applications

    International Nuclear Information System (INIS)

    Žerovnik, Gašper; Trkov, Andrej; Smith, Donald L.; Capote, Roberto

    2013-01-01

    Inherently positive parameters with large relative uncertainties (typically ≳30%) are often considered to be governed by the lognormal distribution. This assumption has the practical benefit of avoiding the possibility of sampling negative values in stochastic applications. Furthermore, it is typically assumed that the correlation coefficients for comparable multivariate normal and lognormal distributions are equivalent. However, this ideal situation is approached only in the linear approximation which happens to be applicable just for small uncertainties. This paper derives and discusses the proper transformation of correlation coefficients between both distributions for the most general case which is applicable for arbitrary uncertainties. It is seen that for lognormal distributions with large relative uncertainties strong anti-correlations (negative correlations) are mathematically forbidden. This is due to the asymmetry that is an inherent feature of these distributions. Some implications of these results for practical nuclear applications are discussed and they are illustrated with examples in this paper. Finally, modifications to the ENDF-6 format used for representing uncertainties in evaluated nuclear data libraries are suggested, as needed to deal with this issue

  6. Transformation of correlation coefficients between normal and lognormal distribution and implications for nuclear applications

    Energy Technology Data Exchange (ETDEWEB)

    Žerovnik, Gašper, E-mail: gasper.zerovnik@ijs.si [Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Trkov, Andrej, E-mail: andrej.trkov@ijs.si [Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Smith, Donald L., E-mail: donald.l.smith@anl.gov [Argonne National Laboratory, 1710 Avenida del Mundo, Coronado, CA 92118-3073 (United States); Capote, Roberto, E-mail: roberto.capotenoy@iaea.org [NAPC–Nuclear Data Section, International Atomic Energy Agency, PO Box 100, Vienna-A-1400 (Austria)

    2013-11-01

    Inherently positive parameters with large relative uncertainties (typically ≳30%) are often considered to be governed by the lognormal distribution. This assumption has the practical benefit of avoiding the possibility of sampling negative values in stochastic applications. Furthermore, it is typically assumed that the correlation coefficients for comparable multivariate normal and lognormal distributions are equivalent. However, this ideal situation is approached only in the linear approximation which happens to be applicable just for small uncertainties. This paper derives and discusses the proper transformation of correlation coefficients between both distributions for the most general case which is applicable for arbitrary uncertainties. It is seen that for lognormal distributions with large relative uncertainties strong anti-correlations (negative correlations) are mathematically forbidden. This is due to the asymmetry that is an inherent feature of these distributions. Some implications of these results for practical nuclear applications are discussed and they are illustrated with examples in this paper. Finally, modifications to the ENDF-6 format used for representing uncertainties in evaluated nuclear data libraries are suggested, as needed to deal with this issue.

  7. Transformation Leadership in Chemical Industry

    KAUST Repository

    Alsherehy, Fahad A.

    2018-01-01

    SABIC is a global leader in diversified chemicals headquartered in Riyadh, Saudi Arabia. It manufactures on a global scale in the Americas, Europe, Middle East and Asia Pacific, making distinctly different kinds of products: chemicals, commodity and high performance plastics, agri-nutrients and metals. The company has more than 35,000 employees worldwide and operates in more than 50 countries, with innovation hubs in five key geographies ヨ USA, Europe, Middle East, South East Asia and North East Asia.

  8. Transformation Leadership in Chemical Industry

    KAUST Repository

    Alsherehy, Fahad A.

    2018-01-16

    SABIC is a global leader in diversified chemicals headquartered in Riyadh, Saudi Arabia. It manufactures on a global scale in the Americas, Europe, Middle East and Asia Pacific, making distinctly different kinds of products: chemicals, commodity and high performance plastics, agri-nutrients and metals. The company has more than 35,000 employees worldwide and operates in more than 50 countries, with innovation hubs in five key geographies ヨ USA, Europe, Middle East, South East Asia and North East Asia.

  9. Polyfluorinated chemicals and transformation products

    Energy Technology Data Exchange (ETDEWEB)

    Knepper, Thomas P. [Univ. of Applied Sciences Fresenius, Idstein (Germany). Inst. for Analytical Research; Lange, Frank Thomas (eds.) [DVGW-Technologiezentrum Wasser, Karlsruhe (Germany)

    2012-07-01

    Due to their unparalleled effectiveness and efficiency, polyfluorinated chemicals (PFC) have become essential in numerous technical applications. However, many PFCs brought to market show limited biodegradability, and their environmental persistence combined with toxic and bioaccumulative potential have become a matter of concern in some instances. This volume highlights the synthesis of PFCs, focusing on substances with improved application and environmental properties, which are a challenge for synthetic chemists. Further, modern mass spectrometric techniques for the detection and identification of biotransformation products of PFCs are described. The sorption and leaching behavior of PFC in soil is also addressed in order to predict their fate in the environment. Several contributions discuss the monitoring of PFCs in European surface, ground and drinking waters, treatment options for PFC removal from drinking water, occurrence in food, and the human biomonitoring of PFCs. (orig.)

  10. Level crossing analysis of chemically induced dynamic nuclear polarization: Towards a common description of liquid-state and solid-state cases

    Energy Technology Data Exchange (ETDEWEB)

    Sosnovsky, Denis V.; Ivanov, Konstantin L., E-mail: ivanov@tomo.nsc.ru [International Tomography Centre of SB RAS, Institutskaya 3a, 630090, Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova 2, 630090, Novosibirsk (Russian Federation); Jeschke, Gunnar [Institut für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland); Matysik, Jörg [Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, D-04103 Leipzig (Germany); Vieth, Hans-Martin [International Tomography Centre of SB RAS, Institutskaya 3a, 630090, Novosibirsk (Russian Federation); Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin (Germany)

    2016-04-14

    Chemically Induced Dynamic Nuclear Polarization (CIDNP) is an efficient method of creating non-equilibrium polarization of nuclear spins by using chemical reactions, which have radical pairs as intermediates. The CIDNP effect originates from (i) electron spin-selective recombination of radical pairs and (ii) the dependence of the inter-system crossing rate in radical pairs on the state of magnetic nuclei. The CIDNP effect can be investigated by using Nuclear Magnetic Resonance (NMR) methods. The gain from CIDNP is then two-fold: it allows one to obtain considerable amplification of NMR signals; in addition, it provides a very useful tool for investigating elusive radicals and radical pairs. While the mechanisms of the CIDNP effect in liquids are well established and understood, detailed analysis of solid-state CIDNP mechanisms still remains challenging; likewise a common theoretical frame for the description of CIDNP in both solids and liquids is missing. Difficulties in understanding the spin dynamics that lead to the CIDNP effect in the solid-state case are caused by the anisotropy of spin interactions, which increase the complexity of spin evolution. In this work, we propose to analyze CIDNP in terms of level crossing phenomena, namely, to attribute features in the CIDNP magnetic field dependence to Level Crossings (LCs) and Level Anti-Crossings (LACs) in a radical pair. This approach allows one to describe liquid-state CIDNP; the same holds for the solid-state case where anisotropic interactions play a significant role in CIDNP formation. In solids, features arise predominantly from LACs, since in most cases anisotropic couplings result in perturbations, which turn LCs into LACs. We have interpreted the CIDNP mechanisms in terms of the LC/LAC concept. This consideration allows one to find analytical expressions for a wide magnetic field range, where several different mechanisms are operative; furthermore, the LAC description gives a way to determine CIDNP sign

  11. Reframing the debate against nuclear weapons

    International Nuclear Information System (INIS)

    Tyson, Rhianna

    2005-01-01

    'Some 35,000 nuclear weapons remain in the arsenals of the nuclear powers, with thousands still deployed on hair-trigger alert. Whatever rationale these weapons may once have had has long since dwindled. Political, moral, and legal constraints on actually using them further undermine their strategic utility without, however, reducing the risks of inadvertent war or proliferation. The objective of nuclear non-proliferation is not helped by the fact that the nuclear weapon States continue to insist that those weapons in their hands enhance security, while in the hands of others they are a threat to world peace. If we were making steady progress towards disarmament, this situation would be less alarming. Unfortunately, the reverse is true.' - United Nations Secretary-General Kofi Annan. 'Something is wrong with the nuclear disarmament and non-proliferation regime. Although seemingly well-equipped with an arsenal of legal and political mechanisms, such as the Nuclear Non-Proliferation Treaty (NPT), the 1996 Advisory Opinion of the International Court of Justice (ICJ), decades' worth of General Assembly (GA) resolutions and even a recent slew of ad-hoc, plurilateral initiatives such as the Proliferation Security Initiative, the regime created to prevent the catastrophe of nuclear war remains inadequate. This insufficiency is even starker when viewed in relation to the regimes controlling other weapons of mass destruction. Despite its own challenges, the Organization for the Prohibition on Chemical Weapons remains relatively well-funded and well-situated to facilitate the implementation of the Chemical Weapons Convention (CWC). Even the Biological and Toxin Weapons Convention (BTWC), while still lacking the necessary verification mechanisms, has managed to effectively criminalize not just the use and threat of use of biological weapons, but also their production, development and stockpiling. Meanwhile, the anti-nuclear regime seems to be faltering. Progress made in

  12. High yield fabrication of chemically reduced graphene oxide field effect transistors by dielectrophoresis

    International Nuclear Information System (INIS)

    Joung, Daeha; Chunder, A; Zhai, Lei; Khondaker, Saiful I

    2010-01-01

    We demonstrate high yield fabrication of field effect transistors (FET) using chemically reduced graphene oxide (RGO) sheets. The RGO sheets suspended in water were assembled between prefabricated gold source and drain electrodes using ac dielectrophoresis. With the application of a backgate voltage, 60% of the devices showed p-type FET behavior, while the remaining 40% showed ambipolar behavior. After mild thermal annealing at 200 deg. C, all ambipolar RGO FET remained ambipolar with increased hole and electron mobility, while 60% of the p-type RGO devices were transformed to ambipolar. The maximum hole and electron mobilities of the devices were 4.0 and 1.5 cm 2 V -1 s -1 respectively. High yield assembly of chemically derived RGO FET will have significant impact in scaled up fabrication of graphene based nanoelectronic devices.

  13. Effective interactions from q-deformed inspired transformations

    International Nuclear Information System (INIS)

    Timoteo, V.S.; Lima, C.L.

    2006-01-01

    From the mass term for the transformed quark fields, we obtain effective contact interactions of the NJL type. The parameters of the model that maps a system of non-interacting transformed fields into quarks interacting via NJL contact terms are discussed

  14. Technical considerations in nuclear terrorism

    International Nuclear Information System (INIS)

    Velardo, G.

    2007-01-01

    Nuclear terrorism is an evil application of nuclear energy, in the same way that chemical and biological terrorism could be considered as the evil side of chemistry and biology. This paper presents two effects of nuclear terrorism. First, dirty bombs or radioactive bombs or radiological dispersion devices (RDDs), and second, crude atom bombs or improvised nuclear devices (INDs). The paper analyses as well the probabilities of an attack, its biological effects and nuclear risk. Experiments carried out so far indicate that the lethal effects produced by RDDs are likely the same that the effects produced by the chemical explosive used in the bomb. These type of bombs are rather bounded to generate panic and have implicit a high cost of decontamination. It will be described the measures to be adopted. INDs will be also considered. Uranium INDs by gun-method are more feasible to be made. They can be disassembled and their components transported to the target place. Plutonium INDs by the implosion-method are complex and required high precision technology. Their disassembly is very difficult

  15. Modulating factors in the expression of radiation-induced oncogenic transformation

    International Nuclear Information System (INIS)

    Hall, E.J.; Hei, T.K.

    1990-01-01

    Many assays for oncogenic transformation have been developed ranging from those in established rodent cell lines where morphological alteration is scored, to those in human cells growing in nude mice where tumor invasiveness is scored. In general, systems that are most quantitaive are also the least relevant in terms of human carcinogenesis and human risk estimation. The development of cell culture systems has made it possible to assess at the cellular level the oncogenic potential of a variety of chemical, physical and viral agents. Cell culture systems afford the opportunity to identify factors and conditions that may prevent or enhance cellular transformation by radiation and chemicals. Permissive and protective factors in radiation-induced transformation include thyroid hormone and the tumor promoter TPA that increase the transformation incidence for a given dose of radiation, and retinoids, selenium, vitamin E, and 5-aminobenzamide that inhibit the expression of transformation. Densely ionizing α-particles, similar to those emitted by radon daughters, are highly effective in inducing transformations and appear to interact in a supra-additive fashion with asbestos fibers. The activation of a known dominant oncogene has not yet been demonstrated in radiation-induced oncogenic transformation. The most likely mechanism for radiation activation of an oncogene would be via the production of a chromosomal translocation. Radiation also efficiently induces deletions and may thus lead to the loss of a suppressor gene

  16. Standard test methods for chemical and spectrochemical analysis of nuclear-Grade silver-indium-cadmium alloys

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1990-01-01

    1.1 These test methods cover procedures for the chemical and spectrochemical analysis of nuclear grade silver-indium-cadmium (Ag-In-Cd) alloys to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Silver, Indium, and Cadmium by a Titration Method 7-15 Trace Impurities by Carrier-Distillation Spectro- chemical Method 16-22 1.3 The values stated in SI units are to be regarded as the standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard and precautionary statements, see Section 5 and Practices E50. 7.1 This test method is applicable to the determination of silver, indium, and cadmium in alloys of approximately 80 % silver, 15 % indium, and 5 % cadmium used in nuclear reactor control r...

  17. The Seismic Fragility Evaluation of an Offsite Transformer according to Aging Effects

    International Nuclear Information System (INIS)

    Kim, Min Kyu; Choi, In Kil

    2008-01-01

    A seismic fragility analysis was performed, especially for an aged electric power transmission system, in this study. A real electric transformer system for Korean Nuclear Power Plants was selected for the seismic fragility evaluation. In the case of a seismic fragility analysis we should use design material properties and conditions. However material properties and environmental conditions of most structures and equipment are changed according to a lapse of time. Aging conditions greatly affect the integrity of the structures and equipment at NPP sites, but it is very difficult to estimate them qualitatively. Integrity of an anchor bolt system was considered with the aging conditions for an electric transformer system. At first, a seismic fragility analysis was performed for a fine condition for an electric transformer system. After that, a seismic fragility analysis according to the fastener of an anchor bolt system was conducted. This study showed that a looser anchor bolt creates seismic responses and seismic fragility changes of more 10%

  18. Possible penetration of nuclear power in fuel and power demand structure in chemical industry

    International Nuclear Information System (INIS)

    Balajka, J.

    1985-01-01

    The possibilities are indicated of the technological applications of high temperature reactors in chemical operations. Nuclear heating may be applied to such processes whose temperature does not 850 degC and pressure is approximately equal to the pressure of helium in the primary circuit of the reactor. The following processes may be implemented: the production of ammonia and methanol, the reduction of iron ore, the implementation of the system of long-distance heat transmission in chemically bound form, etc. The diagram has been designed for the production of ammonia and methanol by steam reforming of methane. The natural gas which enters the process is distributed in the technological and power branches. In the technological branch it is preheated and desulphurized, then mixed with steam and entered the reactor.The outlet mixture of CO, CO 2 , H 2 and Csub(n)Hsub(m) is oxidized with air and following further catalyses a mixture is obtained of N 2 and H 2 in the 1:3 ratio. The power balances and variants are calculated of the distribution of reactor power and its effect on the basic parameters of the technology of the production of NH 3 . (M.D.)

  19. The 40th anniversary of the discovery of NMR-chemical shift and nuclear spin-spin coupling

    International Nuclear Information System (INIS)

    Zhu Zhenghe; Gou Qingquan

    1989-01-01

    After the discovery of NMR Phenomenon in the physics laboratories of E.M.Purcell at Harvard and F.Bloch at Stanford in 1946, W.G.Proctor and F.C.Yu made the successful discovery of NMR-chemical shift and nuclear spin-spin coupling at Stanford in 1950, Which brought NMR spectroscopy from the physics laboratory to the laboratories of many different fields. This is worth memorizing. Retrospecting the past 40 years, it is sure that chemical shift theory will be much more prosperous prospects

  20. Diffusion, Thermal Properties and Chemical Compatibilities of Select MAX Phases with Materials For Advanced Nuclear Systems

    Energy Technology Data Exchange (ETDEWEB)

    Barsoum, Michel [Drexel Univ., Philadelphia, PA (United States); Bentzel, Grady [Drexel Univ., Philadelphia, PA (United States); Tallman, Darin J. [Drexel Univ., Philadelphia, PA (United States); Sindelar, Robert [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Garcia-Diaz, Brenda [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hoffman, Elizabeth [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-04

    The demands of Gen IV nuclear power plants for long service life under neutron irradiation at high temperature are severe. Advanced materials that would withstand high temperatures (up to 1000+ ºC) to high doses in a neutron field would be ideal for reactor internal structures and would add to the long service life and reliability of the reactors. The objective of this work is to investigate the chemical compatibility of select MAX with potential materials that are important for nuclear energy, as well as to measure the thermal transport properties as a function of neutron irradiation. The chemical counterparts chosen for this work are: pyrolytic carbon, SiC, U, Pd, FLiBe, Pb-Bi and Na, the latter 3 in the molten state. The thermal conductivities and heat capacities of non-irradiated MAX phases will be measured.

  1. Development of Procedures for the Analysis of Components of Dumped Chemical Weapons and Their Principal Transformation Products in Sea Water

    International Nuclear Information System (INIS)

    Saveleva, E. I.; Koryagina, N. L.; Radilov, A. S.; Khlebnikova, N. S.; Khrustaleva, V. S.

    2007-01-01

    A package of chemical analytical procedures was developed for the detection of products indicative of the presence of damped chemical weapons in the Baltic Sea. The principal requirements imposed upon the procedures were the following: high sensitivity, reliable identification of target compounds, wide range of components covered by survey analysis, and lack of interferences from sea salts. Thiodiglycol, a product of hydrolysis of sulfur mustard reportedly always detected in the sites of damping chemical weapons in the Baltic Sea, was considered the principal marker. We developed a high-sensitivity procedure for the determination of thiodiglycol in sea water, involving evaporation of samples to dryness in a vacuum concentrator, followed by tert-butyldimethylsilylation of the residue and GCMS analysis in the SIM mode with meta-fluorobenzoic acid as internal reference. The detection limit of thiodiglycol was 0.001 mg/l, and the procedure throughput was up to 30 samples per day. The same procedure, but with BSTFA as derivatizing agent instead of MTBSTFA, was used for preparing samples for survey analysis of nonvolatile components. In this case, full mass spectra were measured in the GCMS analysis. The use of BSTFA was motivated by the fact that trimethylsilyl derivatives are much wider represented in electronic mass spectral databases. The identification of sulfur mustard, volatile transformation products of sulfur mustard and lewisite, as well as chloroacetophenone in sea water was performed by means of GCMS in combination with SPME. The survey GC-MS analysis was focused on the identification of volatile and nonvolatile toxic chemicals whose mass spectra are included in the OPCW database (3219 toxic chemicals, precursors, and transformation products) with the use of AMDIS software (version 2.62). Using 2 GC-MS instruments, we could perform the survey analysis for volatile and nonvolatile components of up to 20 samples per day. Thus, the package of three procedures

  2. Corrosion and solubility in a TSP-buffered chemical environment following a loss of coolant accident: Part 4 – Integrated chemical effects testing

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Amir; LaBrier, Daniel [Department of Nuclear Engineering, University of New Mexico (United States); Blandford, Edward, E-mail: edb@unm.edu [Department of Nuclear Engineering, University of New Mexico (United States); Howe, Kerry [Department of Civil Engineering, University of New Mexico (United States)

    2016-04-15

    Highlights: • Integrated test explored the material release of a postulated large break LOCA. • Aluminum concentration was very low (<0.1 mg/L) throughout the test duration. • Zinc concentration was low (<1 mg/L) in TSP-buffered system. • Calcium release showed two distinguished release zones: prompt and meta-stable. • Copper and iron has no distinguishable concentration up to first 24 h of testing. - Abstract: This paper presents the results of an integrated chemical effects experiment executed under conditions representative of the containment pool following a postulated loss of coolant accident (LOCA) at the Vogtle nuclear power plant, operated by the Southern Nuclear Operating Company (SNOC). This test was conducted for closure of a series of bench scale experiments conducted to investigate the effect of the presence of trisodium phosphate (TSP) on the corrosion and release of aluminum (Howe et al., 2015) and zinc (Pease et al., 2015) from metallic surfaces, and calcium from NUKON fiberglass insulation (Olson et al., 2015) . The integrated test was performed in the Corrosion/Chemical Head Loss Experimental (CHLE) facility with representative amounts of zinc, aluminum, carbon steel, copper, NUKON fiberglass, and latent debris. The test was conducted using borated TSP-buffered solution under a post-LOCA prototypical temperature profile lasting for 30 days. The results presented in this article demonstrate trends for zinc, aluminum, and calcium release that are consistent with separate bench scale testing and previous integrated tests under TSP conditions. The release rate and maximum concentrations of the released materials were slightly different than the separate effect testing as a result of different experimental conditions (temperature, surface area-to-water volume ratio) and/or the presence of other metals and chemicals in the integrated test. Samples of metal coupons and fiberglass were selected for analysis using Scanning Electron Microscopy

  3. Corrosion and solubility in a TSP-buffered chemical environment following a loss of coolant accident: Part 4 – Integrated chemical effects testing

    International Nuclear Information System (INIS)

    Ali, Amir; LaBrier, Daniel; Blandford, Edward; Howe, Kerry

    2016-01-01

    Highlights: • Integrated test explored the material release of a postulated large break LOCA. • Aluminum concentration was very low (<0.1 mg/L) throughout the test duration. • Zinc concentration was low (<1 mg/L) in TSP-buffered system. • Calcium release showed two distinguished release zones: prompt and meta-stable. • Copper and iron has no distinguishable concentration up to first 24 h of testing. - Abstract: This paper presents the results of an integrated chemical effects experiment executed under conditions representative of the containment pool following a postulated loss of coolant accident (LOCA) at the Vogtle nuclear power plant, operated by the Southern Nuclear Operating Company (SNOC). This test was conducted for closure of a series of bench scale experiments conducted to investigate the effect of the presence of trisodium phosphate (TSP) on the corrosion and release of aluminum (Howe et al., 2015) and zinc (Pease et al., 2015) from metallic surfaces, and calcium from NUKON fiberglass insulation (Olson et al., 2015) . The integrated test was performed in the Corrosion/Chemical Head Loss Experimental (CHLE) facility with representative amounts of zinc, aluminum, carbon steel, copper, NUKON fiberglass, and latent debris. The test was conducted using borated TSP-buffered solution under a post-LOCA prototypical temperature profile lasting for 30 days. The results presented in this article demonstrate trends for zinc, aluminum, and calcium release that are consistent with separate bench scale testing and previous integrated tests under TSP conditions. The release rate and maximum concentrations of the released materials were slightly different than the separate effect testing as a result of different experimental conditions (temperature, surface area-to-water volume ratio) and/or the presence of other metals and chemicals in the integrated test. Samples of metal coupons and fiberglass were selected for analysis using Scanning Electron Microscopy

  4. On the effect of response transformations in sequential parameter optimization.

    Science.gov (United States)

    Wagner, Tobias; Wessing, Simon

    2012-01-01

    Parameter tuning of evolutionary algorithms (EAs) is attracting more and more interest. In particular, the sequential parameter optimization (SPO) framework for the model-assisted tuning of stochastic optimizers has resulted in established parameter tuning algorithms. In this paper, we enhance the SPO framework by introducing transformation steps before the response aggregation and before the actual modeling. Based on design-of-experiments techniques, we empirically analyze the effect of integrating different transformations. We show that in particular, a rank transformation of the responses provides significant improvements. A deeper analysis of the resulting models and additional experiments with adaptive procedures indicates that the rank and the Box-Cox transformation are able to improve the properties of the resultant distributions with respect to symmetry and normality of the residuals. Moreover, model-based effect plots document a higher discriminatory power obtained by the rank transformation.

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

    International Nuclear Information System (INIS)

    Henderson, R.A.

    1990-01-01

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

  6. Effects of variable transformations on errors in FORM results

    International Nuclear Information System (INIS)

    Qin Quan; Lin Daojin; Mei Gang; Chen Hao

    2006-01-01

    On the basis of studies on second partial derivatives of the variable transformation functions for nine different non-normal variables the paper comprehensively discusses the effects of the transformation on FORM results and shows that senses and values of the errors in FORM results depend on distributions of the basic variables, whether resistances or actions basic variables represent, and the design point locations in the standard normal space. The transformations of the exponential or Gamma resistance variables can generate +24% errors in the FORM failure probability, and the transformation of Frechet action variables could generate -31% errors

  7. Open-Phase Condition Detecting System for Transformers in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Ha, Che-Wung; Lee, Do-Hwan

    2015-01-01

    Recently, several events involving the loss of one of the three phases of the offsite power circuit occurred in the US nuclear power plants (NPPs).. In some cases, the open-phase condition existed undetected for an extended period and in other case, was not properly responded to. Accordingly, the Nuclear Regulatory Commission (NRC) requested all license holders to take corrective actions to address the open-phase condition. It was also requested that all holders or applicant for a standard design certification (DC) include a description of a protection system to detect and separate the open circuit into design control document (DCD). Currently, NPPs including Duke Energy, Exelon, and institutes including Electric Power Research Institute (EPRI) are working together to resolve issues associated with detecting an open-phase condition. This paper, using Electromagnetic Transients Program (EMTP), presents a system to detect and address the loss of one of three phases of the offsite power circuit connected to main, auxiliary and standby transformers, which is hard to be detected in the current protection system. This paper, using EMTP, presents a system to detect and address the loss of one of three phases of the offsite power circuit running to MT, UAT or SAT which is hard to be detected in the current protection system. The system presented in this paper will be useful not only for the KHNP to meet the NRC requirement, but also for nuclear power plants at home and abroad to take corrective actions to provide protection from a single phase open circuit condition for offsite power sources

  8. Open-Phase Condition Detecting System for Transformers in Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Che-Wung; Lee, Do-Hwan [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Recently, several events involving the loss of one of the three phases of the offsite power circuit occurred in the US nuclear power plants (NPPs).. In some cases, the open-phase condition existed undetected for an extended period and in other case, was not properly responded to. Accordingly, the Nuclear Regulatory Commission (NRC) requested all license holders to take corrective actions to address the open-phase condition. It was also requested that all holders or applicant for a standard design certification (DC) include a description of a protection system to detect and separate the open circuit into design control document (DCD). Currently, NPPs including Duke Energy, Exelon, and institutes including Electric Power Research Institute (EPRI) are working together to resolve issues associated with detecting an open-phase condition. This paper, using Electromagnetic Transients Program (EMTP), presents a system to detect and address the loss of one of three phases of the offsite power circuit connected to main, auxiliary and standby transformers, which is hard to be detected in the current protection system. This paper, using EMTP, presents a system to detect and address the loss of one of three phases of the offsite power circuit running to MT, UAT or SAT which is hard to be detected in the current protection system. The system presented in this paper will be useful not only for the KHNP to meet the NRC requirement, but also for nuclear power plants at home and abroad to take corrective actions to provide protection from a single phase open circuit condition for offsite power sources.

  9. Plutonium contents of broadleaf vegetable crops grown near a nuclear fuel chemical separations facility

    Energy Technology Data Exchange (ETDEWEB)

    McLeod, K W; Alberts, J J; Adriano, D C; Pinder, III, J E

    1984-02-01

    Among agricultural crops, broadleaf vegetables are particularly prone to intercept and retain aerially released contaminants. The plutonium concentration of four broadleaf crops (broccoli, cabbage, lettuce and turnip greens) was determined, when grown in close proximity to a nuclear-fuel chemical-separations facility. Concentrations varied among species, apparently influenced by the crop morphology, with Pu concentrations increasing in the sequence: cabbage < broccoli < turnip greens < lettuce. Washing of the crops significantly reduced the Pu concentration of lettuce, but had no effect on Pu concentration of broccoli and cabbage. The vast majority of Pu found in the crops was due to direct deposition of recently released Pu and resuspension of Pu-bearing soil particles, and was not due to root uptake. Resultant doses from consumption are small relative to the annual background dose.

  10. Ultrasound effects on the electrolytically controlled etching of nuclear track filters (NTFs)

    International Nuclear Information System (INIS)

    Chakarvarti, S.K.; Mahna, S.K.; Sud, L.V.; Singh, P.

    1990-01-01

    The mechanical stirring of the etchant creates tremendous changes in the etching properties of SSNTDs. Ultrasound stirring also produces a number of effects in liquids by giving a rapid movement to etchant. Cavitation is the most probable phenomenon caused by ultrasound and responsible for most of the effects observed in chemical reactions. Microbubbles are created in liquid medium and explosion of these microbubbles is responsible for momentarily rise in temperature. The possible effects of ultrasound on etching of particle tracks in plastic track detectors as nuclear track filters has been studied. The ultrasound effects on V t and V b have been studied in this work. (author). 5 re fs

  11. Advanced Ultrafast Spectroscopy for Chemical Detection of Nuclear Fuel Cycle Materials

    International Nuclear Information System (INIS)

    Villa-Aleman, E.; Houk, A.; Spencer, W.

    2017-01-01

    The development of new signatures and observables from processes related to proliferation activities are often related to the development of technologies. In our physical world, the intensity of observables is linearly related to the input drivers (light, current, voltage, etc.). Ultrafast lasers with high peak energies, opens the door to a new regime where the intensity of the observables is not necessarily linear with the laser energy. Potential nonlinear spectroscopic applications include chemical detection via remote sensing through filament generation, material characterization and processing, chemical reaction specificity, surface phenomena modifications, X-ray production, nuclear fusion, etc. The National Security Directorate laser laboratory is currently working to develop new tools for nonproliferation research with femtosecond and picosecond lasers. Prior to this project, we could only achieve laser energies in the 5 nano-Joule range, preventing the study of nonlinear phenomena. To advance our nonproliferation research into the nonlinear regime we require laser pulses in the milli-Joule (mJ) energy range. We have procured and installed a 35 fs-7 mJ laser, operating at one-kilohertz repetition rate, to investigate elemental and molecular detection of materials in the laboratory with potential applications in remote sensing. Advanced, nonlinear Raman techniques will be used to study materials of interest that are in a matrix of many materials and currently with these nonlinear techniques we can achieve greater than three orders of magnitude signal enhancement. This work studying nuclear fuel cycle materials with nonlinear spectroscopies will advance SRNL research capabilities and grow a core capability within the DOE complex.

  12. Advanced Ultrafast Spectroscopy for Chemical Detection of Nuclear Fuel Cycle Materials

    Energy Technology Data Exchange (ETDEWEB)

    Villa-Aleman, E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Houk, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Spencer, W. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-29

    The development of new signatures and observables from processes related to proliferation activities are often related to the development of technologies. In our physical world, the intensity of observables is linearly related to the input drivers (light, current, voltage, etc.). Ultrafast lasers with high peak energies, opens the door to a new regime where the intensity of the observables is not necessarily linear with the laser energy. Potential nonlinear spectroscopic applications include chemical detection via remote sensing through filament generation, material characterization and processing, chemical reaction specificity, surface phenomena modifications, X-ray production, nuclear fusion, etc. The National Security Directorate laser laboratory is currently working to develop new tools for nonproliferation research with femtosecond and picosecond lasers. Prior to this project, we could only achieve laser energies in the 5 nano-Joule range, preventing the study of nonlinear phenomena. To advance our nonproliferation research into the nonlinear regime we require laser pulses in the milli-Joule (mJ) energy range. We have procured and installed a 35 fs-7 mJ laser, operating at one-kilohertz repetition rate, to investigate elemental and molecular detection of materials in the laboratory with potential applications in remote sensing. Advanced, nonlinear Raman techniques will be used to study materials of interest that are in a matrix of many materials and currently with these nonlinear techniques we can achieve greater than three orders of magnitude signal enhancement. This work studying nuclear fuel cycle materials with nonlinear spectroscopies will advance SRNL research capabilities and grow a core capability within the DOE complex.

  13. Pyrochlore as nuclear waste form. Actinide uptake and chemical stability

    Energy Technology Data Exchange (ETDEWEB)

    Finkeldei, Sarah Charlotte

    2015-07-01

    Radioactive waste is generated by many different technical and scientific applications. For the past decades, different waste disposal strategies have been considered. Several questions on the waste disposal strategy remain unanswered, particularly regarding the long-term radiotoxicity of minor actinides (Am, Cm, Np), plutonium and uranium. These radionuclides mainly arise from high level nuclear waste (HLW), specific waste streams or dismantled nuclear weapons. Although many countries have opted for the direct disposal of spent fuel, from a scientific and technical point of view it is imperative to pursue alternative waste management strategies. Apart from the vitrification, especially for trivalent actinides and Pu, crystalline ceramic waste forms are considered. In contrast to glasses, crystalline waste forms, which are chemically and physically highly stable, allow the retention of radionuclides on well-defined lattice positions within the crystal structure. Besides polyphase ceramics such as SYNROC, single phase ceramics are considered as tailor made host phases to embed a specific radionuclide or a specific group. Among oxidic single phase ceramics pyrochlores are known to have a high potential for this application. This work examines ZrO{sub 2} based pyrochlores as potential nuclear waste forms, which are known to show a high aqueous stability and a high tolerance towards radiation damage. This work contributes to (1) understand the phase stability field of pyrochlore and consequences of non-stoichiometry which leads to pyrochlores with mixed cationic sites. Mixed cationic occupancies are likely to occur in actinide-bearing pyrochlores. (2) The structural uptake of radionuclides themselves was studied. (3) The chemical stability and the effect of phase transition from pyrochlore to defect fluorite were probed. This phase transition is important, as it is the result of radiation damage in ZrO{sub 2} based pyrochlores. ZrO{sub 2} - Nd{sub 2}O{sub 3} pellets

  14. The Unsuspected Roles of Chemistry in Nuclear Power Plants: Special Chemical Technologies for Enhanced Safety and Increased Performance

    Energy Technology Data Exchange (ETDEWEB)

    Sempere Belda, Luis [AREVA NP GmbH, An AREVA and SIEMENS Company, P.O. Box 1109, Erlangen (Germany)

    2008-07-01

    The plant's chemists main responsibility is the establishment and monitoring of an adequate water chemistry to minimize corrosion and in PWRs, to control the neutron flux. But this is by no means the only way in which chemical applications contribute to the performance and safety of a NPP during its entire life: The use of special coatings and treatment protects the plant's components from aggressive environmental conditions. The chemical scale removal in steam generators improves the power output of aging plants, helping even to achieve permissions for NPP life extension. The use of special adhesives can replace welding in complicated or high-dose areas, even underwater. And chemical decontamination is used to remove activity from the components of the primary circuit prior to maintenance or replacement works in order to decrease the radiation exposure of the plant's personnel, employing revolutionary methods of waste minimization to limit the amount of generated radioactive waste to a minimum. The AREVA Group, in its pursue of excellence in all stages of the nuclear cycle, has devoted years of research and development to be able to provide the most advanced technological solutions in this field. The awareness of the existing possibilities will help present and future nuclear professionals, chemists and non-chemists alike, to benefit from the years of experience and continuous development in chemical technologies at the service of the nuclear industry. (authors)

  15. Proceedings of chemical engineering in nuclear technology - national seminar on recent advances in fuel cycle technologies: book of abstracts

    International Nuclear Information System (INIS)

    2014-01-01

    Kalpakkam Regional Centre of Indian Institute of Chemical Engineers is embarking on conducting a series of national seminars on Chemical Engineering in Nuclear Technology 2014. For CHEMENT-2014 the theme was Seminar on recent advances in fuel cycle technologies. The topics covered included research and development, modeling and simulation and equipment development. Papers relevant to INIS are indexed separately

  16. The Effects of Nuclear Weapons

    Energy Technology Data Exchange (ETDEWEB)

    Glasstone, Samuel

    1964-02-01

    This book is a revision of "The Effects of Nuclear Weapons" which was issued in 1957. It was prepared by the Defense Atomic Support Agency of the Department of Defense in coordination with other cognizant governmental agencies and was published by the U.S. Atomc Energy Commission. Although the complex nature of nuclear weapons effects does not always allow exact evaluation, the conclusions reached herein represent the combined judgment of a number of the most competent scientists working the problem. There is a need for widespread public understanding of the best information available on the effects of nuclear weapons. The purpose of this book is to present as accurately as possible, within the limits of national security, a comprehensive summary of this information.

  17. The influence of the "cage effect" on the mechanism of reversible bimolecular multistage chemical reactions in solutions.

    Science.gov (United States)

    Doktorov, Alexander B

    2015-08-21

    Manifestations of the "cage effect" at the encounters of reactants are theoretically treated by the example of multistage reactions in liquid solutions including bimolecular exchange reactions as elementary stages. It is shown that consistent consideration of quasi-stationary kinetics of multistage reactions (possible only in the framework of the encounter theory) for reactions proceeding near reactants contact can be made on the basis of the concepts of a "cage complex." Though mathematically such a consideration is more complicated, it is more clear from the standpoint of chemical notions. It is established that the presence of the "cage effect" leads to some important effects not inherent in reactions in gases or those in solutions proceeding in the kinetic regime, such as the appearance of new transition channels of reactant transformation that cannot be caused by elementary event of chemical conversion for the given mechanism of reaction. This results in that, for example, rate constant values of multistage reaction defined by standard kinetic equations of formal chemical kinetics from experimentally measured kinetics can differ essentially from real values of these constants.

  18. Application of laplace transform method in heavy ion reaction research

    International Nuclear Information System (INIS)

    Wang Jinchuan; Xi Hongfei; Guo Zhongyan; Zhan Wenlong; Zhu Yongtai; Zhou Jianqun; Liu Guanhua

    1993-01-01

    Laplace transform method (LTM) is applied to investigate the effects of different spectroscopy amplifiers parameters on identification of the light charged particles (LCP) emitted from 12 C(46,7 MeV/u) + 58 Ni reaction. The significance of application of LTM in heavy ion experimental nuclear physics is also discussed

  19. Effect of Phase Transformations on Seismic Velocities

    Science.gov (United States)

    Weidner, D. J.; Li, L.; Whitaker, M.; Triplett, R.

    2017-12-01

    The radial velocity structure of the Earth consists of smooth variations of velocities with depth punctuated by abrupt changes of velocity, which are typically due to multivariant phase transformations, where high - low pressure phases can coexist. In this mixed phase region, both the effective shear and bulk moduli will be significantly reduced by the dynamic interaction of the propagating wave and the phase transition if the period of the wave is long enough relative to the kinetic time so that some of the transition can take place. In this presentation, we will give examples from both laboratory studies of phases transitions of Earth minerals and the calculated velocity profile based on our models. We focus on understanding the time limiting factor of the phase transformation in order to extrapolate laboratory results to Earth observations. Both the olivine to ringwoodite transition and KLB-1 partial melting are explored. We find that when the transformation requires diffusion, the kinetics are often slowed down considerably and as a result the diffusivity of atoms become the limiting factor of characteristic time. Specifically Fe-Mg exchange rate in the olivine-ringwoodite phase transition becomes the limiting factor that seismic waves are likely to sample. On the other hand, partial melting is an extremely fast phase transformation at seismic wave periods. We present evidence that ultrasonic waves, with a period of a few tens of nanoseconds, are slowed by the reduction of the effective elastic moduli in this case.

  20. Cluster dynamics transcending chemical dynamics toward nuclear fusion.

    Science.gov (United States)

    Heidenreich, Andreas; Jortner, Joshua; Last, Isidore

    2006-07-11

    Ultrafast cluster dynamics encompasses femtosecond nuclear dynamics, attosecond electron dynamics, and electron-nuclear dynamics in ultraintense laser fields (peak intensities 10(15)-10(20) W.cm(-2)). Extreme cluster multielectron ionization produces highly charged cluster ions, e.g., (C(4+)(D(+))(4))(n) and (D(+)I(22+))(n) at I(M) = 10(18) W.cm(-2), that undergo Coulomb explosion (CE) with the production of high-energy (5 keV to 1 MeV) ions, which can trigger nuclear reactions in an assembly of exploding clusters. The laser intensity and the cluster size dependence of the dynamics and energetics of CE of (D(2))(n), (HT)(n), (CD(4))(n), (DI)(n), (CD(3)I)(n), and (CH(3)I)(n) clusters were explored by electrostatic models and molecular dynamics simulations, quantifying energetic driving effects, and kinematic run-over effects. The optimization of table-top dd nuclear fusion driven by CE of deuterium containing heteroclusters is realized for light-heavy heteroclusters of the largest size, which allows for the prevalence of cluster vertical ionization at the highest intensity of the laser field. We demonstrate a 7-orders-of-magnitude enhancement of the yield of dd nuclear fusion driven by CE of light-heavy heteroclusters as compared with (D(2))(n) clusters of the same size. Prospective applications for the attainment of table-top nucleosynthesis reactions, e.g., (12)C(P,gamma)(13)N driven by CE of (CH(3)I)(n) clusters, were explored.

  1. Effects of isospin and momentum-dependent interactions on thermal properties of nuclear matter

    International Nuclear Information System (INIS)

    Xu Jun; Ma Hongru; Chen Liewen; Li Baoan

    2009-01-01

    In this article, three models with different isospin and momentum dependence are used to study the thermodynamical properties of asymmetric nuclear matter. They are isospin and momentum-dependent MDI interaction constrained by the isospin diffusion data of heavy ion collision, the momentum-independent MID interaction and the isoscalar momentum-dependent eMDYI interaction. Temperature effects of symmetry energy, mechanical and chemical instability and liquid-gas phase transition are analyzed. It is found that for MDI model the temperature effects of the symmetry energy attribute from both the kinetic and potential energy, while only potential part contributes to the decreasing of the symmetry energy for MID and eMDYI models. We also find that the mechanical instability, chemical instability and liquid-gas phase transition are all sensitive to the isospin and momentum dependence and the density dependence of the symmetry energy. (authors)

  2. Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solutions

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solution to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Determination of Uranium 7 Specific Gravity by Pycnometry 15-20 Free Acid by Oxalate Complexation 21-27 Determination of Thorium 28 Determination of Chromium 29 Determination of Molybdenum 30 Halogens Separation by Steam Distillation 31-35 Fluoride by Specific Ion Electrode 36-42 Halogen Distillate Analysis: Chloride, Bromide, and Iodide by Amperometric Microtitrimetry 43 Determination of Chloride and Bromide 44 Determination of Sulfur by X-Ray Fluorescence 45 Sulfate Sulfur by (Photometric) Turbidimetry 46 Phosphorus by the Molybdenum Blue (Photometric) Method 54-61 Silicon by the Molybdenum Blue (Photometric) Method 62-69 Carbon by Persulfate Oxidation-Acid Titrimetry 70 Conversion to U3O8 71-74 Boron by ...

  3. Transformation of iron sulfide to greigite by nitrite produced by oil field bacteria.

    Science.gov (United States)

    Lin, Shiping; Krause, Federico; Voordouw, Gerrit

    2009-05-01

    Nitrate, injected into oil fields, can oxidize sulfide formed by sulfate-reducing bacteria (SRB) through the action of nitrate-reducing sulfide-oxidizing bacteria (NR-SOB). When reservoir rock contains siderite (FeCO(3)), the sulfide formed is immobilized as iron sulfide minerals, e.g. mackinawite (FeS). The aim of our study was to determine the extent to which oil field NR-SOB can oxidize or transform FeS. Because no NR-SOB capable of growth with FeS were isolated, the well-characterized oil field isolate Sulfurimonas sp. strain CVO was used. When strain CVO was presented with a mixture of chemically formed FeS and dissolved sulfide (HS(-)), it only oxidized the HS(-). The FeS remained acid soluble and non-magnetic indicating that it was not transformed. In contrast, when the FeS was formed by adding FeCl(2) to a culture of SRB which gradually produced sulfide, precipitating FeS, and to which strain CVO and nitrate were subsequently added, transformation of the FeS to a magnetic, less acid-soluble form was observed. X-ray diffraction and energy-dispersive spectrometry indicated the transformed mineral to be greigite (Fe(3)S(4)). Addition of nitrite to cultures of SRB, containing microbially formed FeS, was similarly effective. Nitrite reacts chemically with HS(-) to form polysulfide and sulfur (S(0)), which then transforms SRB-formed FeS to greigite, possibly via a sulfur addition pathway (3FeS + S(0) --> Fe(3)S(4)). Further chemical transformation to pyrite (FeS(2)) is expected at higher temperatures (>60 degrees C). Hence, nitrate injection into oil fields may lead to NR-SOB-mediated and chemical mineral transformations, increasing the sulfide-binding capacity of reservoir rock. Because of mineral volume decreases, these transformations may also increase reservoir injectivity.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  5. Adolescents' knowledge of nuclear issues and the effects of nuclear war

    International Nuclear Information System (INIS)

    Roscoe, B.; Goodwin, M.P.

    1987-01-01

    Three hundred fifty-seven college students were surveyed to assess later adolescents' awareness of the status of nuclear arms development and possible effects of a nuclear war on people and the environment. Chi-square analyses were performed to determine whether the frequency of correct responses differed with regard to participants' sex, political orientation, and position toward the United States' possession of nuclear weapons. Results suggest that later adolescents are extremely uninformed regarding the current status of nuclear issues and the consequences of a nuclear war. These data, coupled with findings from previous studies reporting children's and adolescents' concerns and fears about nuclear war, indicate that there is a strong need to educate young people concerning nuclear issues

  6. Status: nuclear and radiochemistry discipline

    International Nuclear Information System (INIS)

    Ramakumar, K.L.

    2013-01-01

    There is no universally accepted definition for the term 'nuclear chemistry'. We may regard nuclear chemistry as an interdisciplinary subject with roots in physics, biology, and chemistry. The basic aspects include among others (i) nuclear reactions and energy levels, (ii) the types and energetics of radioactive decay, (iii) the formation and properties of radioactive elements, (iv) the effect of individual isotopes on chemical and physical properties, and (v) the effects of nuclear radiation on matter. Research in (i) and (ii) is often indistinguishable in purpose and practice from that in nuclear physics, although for nuclear chemists, chemical techniques may play a significant role. (iii) and (iv) can be classified as radiochemistry and isotope chemistry, while (v) falls in the classification of radiation chemistry. There is an urgent need in India also to have similar mechanism. Different universities, research organizations and the education administrators should join hands to address this issue in a focused manner. This is all the more needed urgently as the nuclear power programme and other applications are expected to increase many fold in coming years

  7. Kinetic and thermodynamic modelling of geochemical effects of a nuclear waste storage in granitic environment

    International Nuclear Information System (INIS)

    Made, B.; Fritz, B.

    1993-01-01

    In the world, various experimental sites are selected to study the behavior of different types of source rocks under nuclear waste storage influence. The surrounding rock tested to receive the waste storage must be a stable geological formation. In France, four geological formations are preselected for the feasibility study of repository for spent nuclear fuel at long term: shale, salt, clay and granite. At present time, numerous studies are carried out in Europe (Germany, Belgium, Sweden, Switzerland, United-Kingdom...), in North America (U.S.A. and Canada) and in Japan. Water-rock interactions control the most of rock transformations near the surface of the earth. The rock forming minerals react with the aqueous solutions, the primary minerals dissolution releases ionic species in solution and secondary minerals precipitate if equilibrium or oversaturation is reached. The weathering processes (hydrothermal or not) are always very complicated thus, geochemical codes has been developed to simulate the water-rock interactions. The first generation of codes is based on purely thermodynamic laws without reference to the time dependence of chemical reactions and then the dissolution path calculation refer to the irreversible dissolution of reactants and reversible precipitation of products ([1] to [4]). The system evolution is followed according to the reaction progress ξ which has been introduced in chemical system by Gibbs. Since few years, the experimental studies on the kinetics of minerals dissolution have allowed to take into account of dissolution rates data for the major minerals (silicates, carbonates...). More recently, a new geochemical codes generation appears based on thermodynamic potential and kinetic laws ([5] to [8]). The system evolution is followed according to the reaction time. (authors). 8 figs., 4 tabs., 24 refs

  8. Chemical decontamination solutions: Effects on PWR equipment

    International Nuclear Information System (INIS)

    Pezze, C.M.; Colvin, E.R.; Aspden, R.G.

    1992-01-01

    A critical objective for the nuclear industry is the reduction of personnel exposure to radiation. Reductions have been achieved through industry's radiation management programs including training and radiation awareness concepts. Increased plant maintenance and higher radiation fields at many sites continue to raise concerns. To alleviate the radiation exposure problem, the sources of radiation which contribute to personnel exposure must be removed from the plant. A feasible was of significantly reducing these sources from a Pressurized Water Reactor (PWR) is to chemically decontaminate the entire reactor coolant system (RCS). A program was conducted to determine the technical acceptability of using certain dilute chemical solvent processes for full RCS chemical decontamination. The two processes evaluated were CAN-DEREM and LOMI. The purpose of the program was to define and complete a systematic evaluation of the major issues that need to be addressed for the successful decontamination of the entire RCS and affected portions of the auxiliary systems of a four-loop PWR system. A test program was designed to evaluate the corrosion effects of the two decontamination processes under expected plant conditions. Materials and sample configurations dictated by generic PWR components were evaluated. The testing also included many standard corrosion coupons. The test data were then used to assess the impact of chemical decontamination on the physical condition and operability of the components, equipment and mechanical systems that make up the RCS. An overview of the test program, sample configurations, data and engineering evaluations is presented. The data demonstrate that through detailed engineering evaluations of corrosion data and equipment function, the impact of full RCS chemical decontamination on plant equipment is established

  9. Effects of isospin and momentum dependent interactions on thermal properties of asymmetric nuclear matter

    International Nuclear Information System (INIS)

    Xu Jun; Ma Hongru; Chen Liewen; Li Baoan

    2008-01-01

    Thermal properties of asymmetric nuclear matter are studied within a self-consistent thermal model using an isospin and momentum-dependent interaction (MDI) constrained by the isospin diffusion data in heavy-ion collisions, a momentum-independent interaction (MID), and an isoscalar momentum-dependent interaction (eMDYI). In particular, we study the temperature dependence of the isospin-dependent bulk and single-particle properties, the mechanical and chemical instabilities, and liquid-gas phase transition in hot asymmetric nuclear matter. Our results indicate that the temperature dependence of the equation of state and the symmetry energy are not so sensitive to the momentum dependence of the interaction. The symmetry energy at fixed density is found to generally decrease with temperature and for the MDI interaction the decrement is essentially due to the potential part. It is further shown that only the low momentum part of the single-particle potential and the nucleon effective mass increases significantly with temperature for the momentum-dependent interactions. For the MDI interaction, the low momentum part of the symmetry potential is significantly reduced with increasing temperature. For the mechanical and chemical instabilities as well as the liquid-gas phase transition in hot asymmetric nuclear matter, our results indicate that the boundaries of these instabilities and the phase-coexistence region generally shrink with increasing temperature and are sensitive to the density dependence of the symmetry energy and the isospin and momentum dependence of the nuclear interaction, especially at higher temperatures

  10. Study on the welding continuous cooling transformation and weldability of SA508Gr4 steel for nuclear pressure vessels

    International Nuclear Information System (INIS)

    Bai, Qingwei; Ma, Yonglin; Xing, Shuqing; Chen, Zhongyi

    2017-01-01

    SA508Gr4 is a newly developed high-strength steel for nuclear reactor pressure vessels. Its welding characteristics remain largely unexplored. In this work, the simulated heat affected zone continuous cooling transformation (SH-CCT) diagram of SA508Gr4 steel was constructed and the high-temperature cooling phase compositions and the properties of the heat affected zone (HAZ) were characterized using dilatometry and microscopic tests. The results show that the phase transformation in the HAZ was divided into bainite and martensite transformation stages. When 4.6 ≤ t_8_/_5 (the HAZ cooling time from 800 C to 500 C) ≤ 15 s, lath-shaped martensite was fully developed, resulting in extensive hardening and cold cracking in the HAZ, while the cooling time required to form the bainite completely exceeds 1 200 s. Thus, to improve weld quality, preheating to 196 C or higher is recommended.

  11. Study on the welding continuous cooling transformation and weldability of SA508Gr4 steel for nuclear pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Qingwei; Ma, Yonglin; Xing, Shuqing; Chen, Zhongyi [Inner Mongolia Univ. of Science and Technology, Baotou (China). School of Material and Metallurgy; Kang, Xiaolan [Baotou Vocational and Technical College (China)

    2017-02-15

    SA508Gr4 is a newly developed high-strength steel for nuclear reactor pressure vessels. Its welding characteristics remain largely unexplored. In this work, the simulated heat affected zone continuous cooling transformation (SH-CCT) diagram of SA508Gr4 steel was constructed and the high-temperature cooling phase compositions and the properties of the heat affected zone (HAZ) were characterized using dilatometry and microscopic tests. The results show that the phase transformation in the HAZ was divided into bainite and martensite transformation stages. When 4.6 ≤ t{sub 8/5} (the HAZ cooling time from 800 C to 500 C) ≤ 15 s, lath-shaped martensite was fully developed, resulting in extensive hardening and cold cracking in the HAZ, while the cooling time required to form the bainite completely exceeds 1 200 s. Thus, to improve weld quality, preheating to 196 C or higher is recommended.

  12. Effects of composition on properties in an 11-component nuclear waste glass system

    International Nuclear Information System (INIS)

    Chick, L.A.; Piepel, G.F.; Mellinger, G.B.; May, R.P.; Gray, W.J.; Buckwalter, C.Q.

    1981-09-01

    Ninety simplified nuclear waste glass compositions within an 11-component oxide composition matrix were tested for crystallinity, viscosity, volatility, and chemical durability. Empirical models of property response as a function of glass composition were developed using statistical experimental design and modeling techniques. A new statistical technique was developed to calculate the effects of oxide components on each property. Independent melts were used to check the prediction accuracy of the models

  13. Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium nitrate solutions

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium nitrate solutions to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Plutonium by Controlled-Potential Coulometry Plutonium by Amperometric Titration with Iron(II) Plutonium by Diode Array Spectrophotometry Free Acid by Titration in an Oxalate Solution 8 to 15 Free Acid by Iodate Precipitation-Potentiometric Titration Test Method 16 to 22 Uranium by Arsenazo I Spectrophotometric Test Method 23 to 33 Thorium by Thorin Spectrophotometric Test Method 34 to 42 Iron by 1,10-Phenanthroline Spectrophotometric Test Method 43 to 50 Impurities by ICP-AES Chloride by Thiocyanate Spectrophotometric Test Method 51 to 58 Fluoride by Distillation-Spectrophotometric Test Method 59 to 66 Sulfate by Barium Sulfate Turbidimetric Test Method 67 to 74 Isotopic Composition by Mass Spectrom...

  14. Plasma-chemical processes and systems

    International Nuclear Information System (INIS)

    Castro B, J.

    1987-01-01

    The direct applications of plasma technology on chemistry and metallurgy are presented. The physical fundaments of chemically active non-equilibrium plasma, the reaction kinetics, and the physical chemical transformations occuring in the electrical discharges, which are applied in the industry, are analysed. Some plasma chemical systems and processes related to the energy of hydrogen, with the chemical technology and with the metallurgy are described. Emphasis is given to the optimization of the energy effectiveness of these processes to obtain reducers and artificial energetic carriers. (M.C.K.) [pt

  15. Coupling of high temperature nuclear reactor with chemical plant by means of steam loop with heat pump

    Directory of Open Access Journals (Sweden)

    Kopeć Mariusz

    2017-01-01

    Full Text Available High temperature nuclear reactors (HTR can be used as an excellent, emission-free source of technological heat for various industrial applications. Their outlet helium temperature (700°-900°C allows not only for heat supply to all processes below 600°C (referred to as “steam class”, but also enables development of clean nuclear-assisted hydrogen production or coal liquefaction technologies with required temperatures up to 900°C (referred to as “chemical class”. This paper presents the results of analyses done for various configurations of the steam transport loop coupled with the high-temperature heat pump designed for “chemical class” applications. The advantages and disadvantages as well as the key issues are discussed in comparison with alternative solutions, trying to answer the question whether the system with the steam loop and the hightemperature heat pump is viable and economically justified.

  16. Conditionally controlling nuclear trafficking in yeast by chemical-induced protein dimerization.

    Science.gov (United States)

    Xu, Tao; Johnson, Cole A; Gestwicki, Jason E; Kumar, Anuj

    2010-11-01

    We present here a protocol to conditionally control the nuclear trafficking of target proteins in yeast. In this system, rapamycin is used to heterodimerize two chimeric proteins. One chimera consists of a FK506-binding protein (FKBP12) fused to a cellular 'address' (nuclear localization signal or nuclear export sequence). The second chimera consists of a target protein fused to a fluorescent protein and the FKBP12-rapamycin-binding (FRB) domain from FKBP-12-rapamycin associated protein 1 (FRAP1, also known as mTor). Rapamycin induces dimerization of the FKBP12- and FRB-containing chimeras; these interactions selectively place the target protein under control of the cell address, thereby directing the protein into or out of the nucleus. By chemical-induced dimerization, protein mislocalization is reversible and enables the identification of conditional loss-of-function and gain-of-function phenotypes, in contrast to other systems that require permanent modification of the targeted protein. Yeast strains for this analysis can be constructed in 1 week, and the technique allows protein mislocalization within 15 min after drug treatment.

  17. Corrosion surveillance of the chemical decontamination process in Kuosheng nuclear power plant

    International Nuclear Information System (INIS)

    Wang, L.H.

    2002-01-01

    The Piping Recirculation System (RRS) and reactor water clean-up system (RWCU) of Kuosheng Nuclear Power Plant of Taiwan Power Company were decontaminated by CORD process of Framatome ANP GmbH during the outage at October 2001. This is the first time that CORD process was adopted and applied in Taiwan Nuclear Power Plant. To verify minor corrosion damage and correct process control, the material corrosion condition was monitored during all the stages of the chemical decontamination work. Three kinds of specimen were adopted in this corrosion monitoring, including corrosion coupons for weight loss measurements, electrochemical specimens for on-line corrosion monitoring, and WOL specimens (wedge opening loaded) for stress corrosion evaluation. The measured metal losses from nine coupon materials did not reveal any unexpected or intolerable high corrosion damage from the CORD UV or CORD CS processes. The coupon materials included type 304 stainless steel (SS) with sensitized and as-received thermal history, type 308 weld filler, type CF8 cast SS, nickel base alloy 182 weld filler, Inconel 600, Stellite 6 hard facing alloy, NOREM low cobalt hard facing alloy, and A106B carbon steel (CS). The electrochemical noise (ECN) measurements from three-electrode electrochemical probe precisely depicted the metal corrosion variation with the decontamination process change. Most interestingly, the estimated trend of accumulated metal loss is perfectly corresponding to the total removed activities. The ECN measurements were also used for examining the effect of different SS oxide films pre-formed in NWC and HWC on the decontamination efficiency, and for evaluating the galvanic effect of CS with SS. The existing cracks did not propagate further during the decontamination. The average decontamination factors achieved were 50.8 and 4.2 respectively for RRS and RWCU. (authors)

  18. Cloning retinoid and peroxisome proliferator-activated nuclear receptors of the Pacific oyster and in silico binding to environmental chemicals.

    Directory of Open Access Journals (Sweden)

    Susanne Vogeler

    Full Text Available Disruption of nuclear receptors, a transcription factor superfamily regulating gene expression in animals, is one proposed mechanism through which pollution causes effects in aquatic invertebrates. Environmental pollutants have the ability to interfere with the receptor's functions through direct binding and inducing incorrect signals. Limited knowledge of invertebrate endocrinology and molecular regulatory mechanisms, however, impede the understanding of endocrine disruptive effects in many aquatic invertebrate species. Here, we isolated three nuclear receptors of the Pacific oyster, Crassostrea gigas: two isoforms of the retinoid X receptor, CgRXR-1 and CgRXR-2, a retinoic acid receptor ortholog CgRAR, and a peroxisome proliferator-activated receptor ortholog CgPPAR. Computer modelling of the receptors based on 3D crystal structures of human proteins was used to predict each receptor's ability to bind to different ligands in silico. CgRXR showed high potential to bind and be activated by 9-cis retinoic acid and the organotin tributyltin (TBT. Computer modelling of CgRAR revealed six residues in the ligand binding domain, which prevent the successful interaction with natural and synthetic retinoid ligands. This supports an existing theory of loss of retinoid binding in molluscan RARs. Modelling of CgPPAR was less reliable due to high discrepancies in sequence to its human ortholog. Yet, there are suggestions of binding to TBT, but not to rosiglitazone. The effect of potential receptor ligands on early oyster development was assessed after 24h of chemical exposure. TBT oxide (0.2μg/l, all-trans retinoic acid (ATRA (0.06 mg/L and perfluorooctanoic acid (20 mg/L showed high effects on development (>74% abnormal developed D-shelled larvae, while rosiglitazone (40 mg/L showed no effect. The results are discussed in relation to a putative direct (TBT disruption effect on nuclear receptors. The inability of direct binding of ATRA to CgRAR suggests

  19. Nuclear Material Control and Accountability System Effectiveness Tool (MSET)

    International Nuclear Information System (INIS)

    Powell, Danny H.; Elwood, Robert H. Jr.; Roche, Charles T.; Campbell, Billy J.; Hammond, Glenn A.; Meppen, Bruce W.; Brown, Richard F.

    2011-01-01

    A nuclear material control and accountability (MC and A) system effectiveness tool (MSET) has been developed in the United States for use in evaluating material protection, control, and accountability (MPC and A) systems in nuclear facilities. The project was commissioned by the National Nuclear Security Administration's Office of International Material Protection and Cooperation. MSET was developed by personnel with experience spanning more than six decades in both the U.S. and international nuclear programs and with experience in probabilistic risk assessment (PRA) in the nuclear power industry. MSET offers significant potential benefits for improving nuclear safeguards and security in any nation with a nuclear program. MSET provides a design basis for developing an MC and A system at a nuclear facility that functions to protect against insider theft or diversion of nuclear materials. MSET analyzes the system and identifies several risk importance factors that show where sustainability is essential for optimal performance and where performance degradation has the greatest impact on total system risk. MSET contains five major components: (1) A functional model that shows how to design, build, implement, and operate a robust nuclear MC and A system (2) A fault tree of the operating MC and A system that adapts PRA methodology to analyze system effectiveness and give a relative risk of failure assessment of the system (3) A questionnaire used to document the facility's current MPC and A system (provides data to evaluate the quality of the system and the level of performance of each basic task performed throughout the material balance area (MBA)) (4) A formal process of applying expert judgment to convert the facility questionnaire data into numeric values representing the performance level of each basic event for use in the fault tree risk assessment calculations (5) PRA software that performs the fault tree risk assessment calculations and produces risk importance

  20. Application of atomic mutations included in nuclear reactions, 40Ar(γ, p)39Cl(β decay)39Ar, to surface study

    International Nuclear Information System (INIS)

    Ohkuma, Juzo

    1987-01-01

    It has been found that the nuclear transformation processes which are initiated by photonuclear reactions can be used for studying the adsorption and chemical reactions taking place on solid surfaces. Chemically reactive 39 Cl was produced by irradiating 40 Ar with high-energy bremsstrahlung, and its blow was directed onto several material surfaces. The amount of chlorine adsorption was ascertained by detecting its radioactivity. Desorption without heating the adsorber samples inevitably occurred owing to the nuclear decay of 39 Cl. The adsorption and desorption rates were compared for several elements. A fast growth of oxide islands on sample surfaces was observed during the adsorption-desorption process. (author)

  1. Effects of phase transformation of steam-water relative permeabilities

    Energy Technology Data Exchange (ETDEWEB)

    Verma, A.K.

    1986-03-01

    A combined theoretical and experimental study of steam-water relative permeabilities (RPs) was carried out. First, an experimental study of two-phase concurrent flow of steam and water was conducted and a set of RP curves was obtained. These curves were compared with semi-empirical and experimental results obtained by other investigators for two-phase, two-component flow (oil/gas; gas/water; gas/oil). It was found that while the wetting phase RPs were in good agreement, RPs for the steam phase were considerably higher than the non-wetting phase RPs in two-component systems. This enhancement of steam RP is attributed to phase transformation effects at the pore level in flow channels. The effects of phase transformation were studied theoretically. This study indicates that there are two separate mechanisms by which phase transformation affects RP curves: (1) Phase transformation is converging-diverging flow channels can cause an enhancement of steam phase RP. In a channel dominated by steam a fraction of the flowing steam condenses upstream from the constriction, depositing its latent heat of condensation. This heat is conducted through the solid grains around the pore throat, and evaporation takes place downstream from it. Therefore, for a given bulk flow quality; a smaller fraction of steam actually flows through the throat segments. This pore-level effect manifests itself as relative permeability enhancement on a macroscopic level; and (2) phase transformation along the interface of a stagnant phase and the phase flowing around it controls the irreducible phase saturation. Therefore, the irreducible phase saturation in steam-water flow will depend, among other factors, on the boundary conditions of the flow.

  2. The study of the radiation chemical transformation of the hexane on the surface of aluminium by IR-spectroscopy method

    International Nuclear Information System (INIS)

    Rimikhanova, A.N.

    2006-01-01

    Full text: In this work the experimental results of the radiation-chemical transformation of hexane on the aluminum surface obtained by IR spectroscopy method at room temperature have been presented. The metallic aluminum plates which was obtained by stage pressing granules by mark of AD-00 with the reflection coefficient R=0,85 in the middle infrared range of waves length λ=15 ± 2,2 mkm were used. As an adsorbate unsaturated vapors of hexane were used, the absorption of which was being carried out at the room temperature by the method. The radiation of system was carried out with γ-quanta of Co 60 with doze rate of 1,03 Gy/s - 1, and the absorbed doze in the system was (0,5-2)10 4 Gy. IR reflection spectra when beams fall on the sample under angle near the slipping were measured in diapason of 3600-650 cm - 1 by the spectrophotometer S pecord 71IR . The radiation chemical decomposition of hexane in heterosystem was being traced in stretching (3000-2700 cm - 1) and deformation (1500-1300 cm - 1) vibration diapasons of C-H bonds. The analysis of IR reflection spectra of Al-ads.hexane heterosystem showed that the main products of radiation chemical transformation are hydrocarbons C1-C5, olefins: propylene, butene-1, hexene-1, transhexene-3 and hydrocarbons more heavy than hexane. In frequency range of 1700-2000 cm - 1 the absorption bands of Al-H vibration which concern to aluminum hydrides are founded. By increasing of radiation dose the tendency of increasing of hydrogen accumulation as aluminum hydrides has been established

  3. Effects of combined exposure of F344 rats to inhaled Plutonium-239 dioxide and a chemical carcinogen (NNK)

    Energy Technology Data Exchange (ETDEWEB)

    Lundgren, D.L.; Carlton, W.W. [Purdue Univ., Lafayette, IN (United States); Griffith, W.C. [and others

    1995-12-01

    Workers in nuclear weapons facilities have a significant potential for exposure to chemical carcinogens and to radiation from external sources or from internally deposited radionuclides such as {sup 239}Pu. Although the carcinogenic effects of inhaled {sup 239}Pu and many chemicals have been studied individually, very little information is available on their combined effects. One chemical carcinogen that workers could be exposed to via tobacco smoke is the tobacco-specific nitrosamine 4-(N-methyl-n-nitrosamino)-1-(3-pyridyl)-1(3-pyridyl)-1-butanone (NNK), a product of tobacco curing and the pyrolysis of nicotine in tobacco. NNK causes lung tumors in rats, regardless of the route of administration and to a lesser extent liver, nasal, and pancreatic tumors. From the results presented, it can be concluded that exposure to a chemical carcinogen (NNK) in combination with {alpha}-particle radiation from inhaled {sup 239}PuO{sub 2} acts in, at best, an additive manner in inducing lung cancer in rats.

  4. High-throughput screening of chemical effects on ...

    Science.gov (United States)

    Disruption of steroidogenesis by environmental chemicals can result in altered hormone levels causing adverse reproductive and developmental effects. A high-throughput assay using H295R human adrenocortical carcinoma cells was used to evaluate the effect of 2,060 chemical samples on steroidogenesis via HPLC-MS/MS quantification of 10 steroid hormones, including progestagens, glucocorticoids, androgens, and estrogens. The study employed a three stage screening strategy. The first stage established the maximum tolerated concentration (MTC; >70% viability) per sample. The second stage quantified changes in hormone levels at the MTC while the third stage performed concentration-response (CR) on a subset of samples. At all stages, cells were pre-stimulated with 10 µM forskolin for 48 h to induce steroidogenesis followed by chemical treatment for 48 h. Of the 2,060 chemical samples evaluated, 524 samples were selected for six-point CR screening, based in part on significantly altering at least 4 hormones at the MTC. CR screening identified 232 chemical samples with concentration-dependent effects on 17β-estradiol and/or testosterone, with 411 chemical samples showing an effect on at least one hormone across the steroidogenesis pathway. Clustering of the concentration-dependent chemical-mediated steroid hormone effects grouped chemical samples into five distinct profiles generally representing putative mechanisms of action, including CYP17A1 and HSD3B inhibition. A d

  5. Establishment of data base of regional seismic recordings from earthquakes, chemical explosions and nuclear explosions in the Former Soviet Union

    Energy Technology Data Exchange (ETDEWEB)

    Ermolenko, N.A.; Kopnichev, Yu.F.; Kunakov, V.G.; Kunakova, O.K.; Rakhmatullin, M.Kh.; Sokolova, I.N.; Vybornyy, Zh.I. [AN SSSR, Moscow (Russian Federation). Inst. Fiziki Zemli

    1995-06-01

    In this report results of work on establishment of a data base of regional seismic recordings from earthquakes, chemical explosions and nuclear explosions in the former Soviet Union are described. This work was carried out in the Complex Seismological Expedition (CSE) of the Joint Institute of Physics of the Earth of the Russian Academy of Sciences and Lawrence Livermore National Laboratory. The recording system, methods of investigations and primary data processing are described in detail. The largest number of digital records was received by the permanent seismic station Talgar, situated in the northern Tien Shan, 20 km to the east of Almaty city. More than half of the records are seismograms of underground nuclear explosions and chemical explosions. The nuclear explosions were recorded mainly from the Semipalatinsk test site. In addition, records of the explosions from the Chinese test site Lop Nor and industrial nuclear explosions from the West Siberia region were obtained. Four records of strong chemical explosions were picked out (two of them have been produced at the Semipalatinsk test site and two -- in Uzbekistan). We also obtained 16 records of crustal earthquakes, mainly from the Altai region, close to the Semipalatinsk test site, and also from the West China region, close to the Lop Nor test site. In addition, a small number of records of earthquakes and underground nuclear explosions, received by arrays of temporary stations, that have been working in the southern Kazakhstan region are included in this report. Parameters of the digital seismograms and file structure are described. Possible directions of future work on the digitizing of unique data archive are discussed.

  6. A program to assess microbial impacts on nuclear waste containment

    International Nuclear Information System (INIS)

    Horn, J.; Meike, A.

    1996-01-01

    In this paper we discuss aspects of a comprehensive program to identify and bound potential effects of microorganisms on long-term nuclear waste containment, using as examples, studies conducted within the Yucca Mountain Project. A comprehensive program has been formulated which cuts across standard disciplinary lines to address the specific concerns of microbial activity in a radioactive waste repository. Collectively, this program provides bounding parameters of microbial activities that modify the ambient geochemistry and hydrology, modify corrosion rates, and transport and transform radionuclides under conditions expected to be encountered after geological waste emplacement. This program is intended to provide microbial reaction rates and bounding conditions in a form that can be integrated into existing chemical and hydrological models. The inclusion of microbial effects will allow those models to more accurately assess long term repository integrity

  7. Transformation behavior, chemical composition, surface topography and bending properties of five selected 0.016" x 0.022" NiTi archwires.

    Science.gov (United States)

    Fischer-Brandies, Helge; Es-Souni, Mohammed; Kock, Norman; Raetzke, Klaus; Bock, Ole

    2003-03-01

    The aim of this study was to characterize five selected commercial NiTi archwires in terms of their transformation behavior, chemical composition, surface topography and mechanical properties (at temperatures of 22 degrees C, 37 degrees C and 60 degrees C). The rectangular orthodontic archwires investigated were Neo Sentalloy F80 (GAC, Central Islip, NY, USA), 35 degrees C Thermo-Active Copper NiTi (A-Company/Ormco, Glendora, CA, USA), Rematitan "Lite" (Dentaurum, Pforzheim, Germany), Titanol SE S (Forestadent, Pforzheim, Germany) and Titanal (Lancer, San Marcos, CA, USA) in size 0.016" x 0.022". The chemical composition and surface topography were analyzed by energy dispersive X-ray spectroscopy using an analytical scanning electron microscope (XL30, EDAX SUTW Saphire Detector; Philips, Eindhoven, Netherlands). The transition temperatures were measured by means of differential scanning calorimetry (DSC; Perkin-Elmer Pyris 1, Perkin-Elmer, Fremont, CA, USA) in a range of - 80 degrees C to + 80 degrees C. The mechanical properties and their dependence on temperature were determined by means of 3-point bending tests. The binary archwire materials were characterized by a two-phase structure (NiTi matrix and Ni3Ti4 precipitates). The SEM analyses revealed abradant residues in virtually all archwires, while DSC revealed complex transformation properties. In addition to the martensitic and austenitic transformations, an R-phase transformation was also detected. The bending tests showed pronounced loading and unloading plateaus. The martensitic archwires (Neo Sentalloy F80, 35 degrees C Thermo-Active Copper NiTi) were found to have a lower strength than the martensitic-austenitic (Rematitan "Lite") and the austenitic archwires (Titanol SE S, Titanal). With increasing temperature (in the range from 22 degrees C to 60 degrees C) a linear rise in the plateau forces was recorded. When assessing the quality of archwires, account should be taken of the surface quality, as it is

  8. Effects of tungsten on continuous cooling transformation characteristics of microalloyed steels

    International Nuclear Information System (INIS)

    Zhao, Jingwei; Jiang, Zhengyi; Kim, Ji Soo; Lee, Chong Soo

    2013-01-01

    Highlights: ► W has a positive effect on refining the austenite grains and precipitates. ► W shifts the ranges of transformation products to the right side of CCT diagram. ► W addition induces increased austenitisation starting and finishing temperatures. ► The critical cooling rate for phase transformation is decreased after W addition. - Abstract: Continuous cooling transformation (CCT) characteristics of microalloyed steels with different tungsten (W) contents (0, 0.1 and 1 wt.%) were investigated to obtain the necessary information for heat treatment of these steels. The effects of W addition on the sizes of prior austenite grains and precipitates were analysed. CCT diagrams were obtained by varying the cooling rates from 0.1 to 120 °C/s. Transformation characteristics were determined by using dilatometer test, microscopic observation and hardness measurement. The results showed that W had a positive effect on the refinement of prior austenite grains and precipitates. The CCT diagrams exhibited that the ranges of transformation products were shifted to the right side of the diagram when the W content increased. CCT diagram for steel with 0.1% W was similar in shape to that without W. The addition of 1% W induced two separated transformation ranges in the cooling rate range of 0.1 to 1 °C/s in the diagram. Both the austenitisation starting and finishing temperatures were raised as W was added. W addition induced decreased critical cooling rates for phase transformations and obtaining complete ferrite + pearlite microstructures. The martensite transformation temperature was decreased after W addition. The addition of W caused increased hardness, and the hardness obeyed an exponential type relationship with cooling rate

  9. Nuclear energy and society

    International Nuclear Information System (INIS)

    Bakacs, Istvan; Czeizel, Endre; Hajdu, Janos; Marx, Gyoergy.

    1984-01-01

    The text of a round-table discussion held on the occasion of the 50th anniversary of the discovery of neutron is given. The participants were the Chief Engineer of the Paks Nuclear Power Plant, the first nuclear power plant in Hungary started in November 1982, a geneticist treating the problems of genetic damages caused by nuclear and chemical effects, a nuclear physicist and a journalist interested in the social aspects of nuclear energy. They discussed the political, economical and social problems of nuclear energy in the context of its establishment in Hungary. (D.Gy.)

  10. Alloying effect on martensite transformation in stainless steels

    International Nuclear Information System (INIS)

    Gulyaev, A.P.; Shlyamnev, A.P.; Sorokina, N.A.

    1975-01-01

    The effect of cobalt, nickel, molybdenum on the martensite transformation kinetics in stainless steels containing 9 to 13% Cr has been studied. Cobalt in Fe-Cr base alloys decreases the temperature of the Msub(in) and Msub(fin) points without a considerable decrease of the martensite phase amount after the transformation. Nickel reduces the martensite transformation temperature range, the nickel effect being enhanced in the presence of cobalt, which is characterized by a change of the linear dependence Msub(in)=f(%Ni) for a quadratic one. Molybdenum decreases the temperature of the Msub(in) and Msub(fin) points intensively, thus, substantially increasing the residual austenite amount. In the steels investigated Ni and Co decrease, whereas Mo increases, to some extent, the temperature of the reverse a-γ-transformation. The reduction of chromium content from 13 to 9% stimulates the martensite transformation initiation, that is why, in alloys containing 9% Cr, the increase in the contents of Ni, Co., Mo with the martensite structure maintained is possible. A further alloying of steel containing 13% Cr with these elements is rather limited due to the inhibition of the martensite transformation

  11. Evaluation on Safety of Stainless Steels in Chemical Decontamination Process with Immersion Type of Reactor Coolant Pump for Nuclear Reactor

    International Nuclear Information System (INIS)

    Kim, Seong Jong; Han, Min Su; Jang, Seok Ki; Kim, Ki Joon

    2011-01-01

    Due to commercialization of nuclear power, most countries have taken interest in decontamination process of nuclear power plant and tried to develop a optimum process. Because open literature of the decontamination process are rare, it is hard to obtain skills on decontamination of foreign country and it is necessarily to develop proper chemical decontamination process system in Korea. In this study, applicable possibility in chemical decontamination for reactor coolant pump (RCP) was investigated for the various stainless steels. The stainless steel (STS) 304 showed the best electrochemical properties for corrosion resistance and the lowest weight loss ratio in chemical decontamination process with immersion type than other materials. However, the pitting corrosion was generated in both STS 415 and STS 431 with the increasing numbers of cycle. The intergranular corrosion in STS 431 was sporadically observed. The sizes of their pitting corrosion also increased with increasing cycle numbers

  12. An Investigation into the Physico-chemical Properties of Transformer Oil Blends with Antioxidants extracted from Turmeric Powder

    Science.gov (United States)

    Dukhi, Veresha; Bissessur, Ajay; Ngila, Catherine Jane; Ijumba, Nelson Mutatina

    2013-07-01

    The blending of transformer oil (used mainly as an insulating oil) with appropriate synthetic antioxidants, such as BHT (2,6-di-tert-butyl-4-methylphenol) and DBP (2,6-di-tert-butylphenol) have been previously reported. This article is focused on the use of antioxidant extracts from turmeric (Curcuma longa), a natural source. Turmeric is well known for its antimicrobial, antioxidant and anticarcinogenic properties owing to the active nature of its components. Extracts from powdered turmeric were subsequently blended into naphthenic-based uninhibited virgin transformer oil, hereinafter referred to as extract-oil blends (E-OB). Thin-layer chromatography (TLC) of the oil blends revealed that five components extracted from turmeric powder were successfully blended into the oil. Subsequent gas chromatography-mass spectrometry (GC-MS) analysis confirmed the presence of the compounds: curcumene, sesquiphellandrene, ar-turmerone, turmerone and curlone. Thermogravimetric analysis (TGA) of the extract-oil blends, containing various levels of extracts, revealed an average temperature shift of ˜8.21°C in the initial onset of degradation in comparison to virgin non-blended oil. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay showed that an increase in the mass aliquot of turmeric extracts in the transformer oil increased the free radical scavenging activity of the oil. Electrical properties of the oil investigated showed that the dissipation factor in the blended oil was found to be lower than that of virgin transformer oil. Evidently, a lower dissipation value renders the oil blend as a superior insulator over normal virgin non-blended oil. This investigation elucidated improved physico-chemical properties of transformer oil blended with turmeric antioxidant extracts.

  13. β-carotene and canthaxanthin inhibit chemically- and physically-induced transformation in 10T1/2 cells

    International Nuclear Information System (INIS)

    Pung, A.; Rundhaug, J.E.; Yoshizawa, C.N.; Bertram, J.S.

    1988-01-01

    We have studied the effects of β-carotene (β-C), a vitamin A precursor of plant origin, and canthaxanthin (CTX), a non-provitamin A carotenoid, on the neoplastic transformation of C3H/10T1/2 murine fibroblast cells. We show that both β-C and CTX inhibit 3-methylcholanthrene (MCA)-induced transformation. Both carotenoids failed to inhibit X-ray-induced transformation when the cells were treated prior to and during irradiation. However, when the drugs were added 1 week after X-irradiation and maintained in the medium thereafter, both carotenoids inhibited subsequent development of transformed foci in a dose-dependent manner. Again, CTX was more effective than β-C. The inhibition of MCA-induced transformation was reversible; upon removal of the drug, transformed foci developed within 2 weeks, indicating that the carotenoids were not specifically toxic to initiated cells. Although both carotenoids caused a small dose-dependent decrease in the growth rate of both parental and initiated 10T1/2 cells, they did not markedly affect colony size or number when the cells were treated as in the transformation assays, nor did they influence the expression of neoplasia of two transformed cell lines. We suggest that the carotenoids' lipid anti-oxidant properties may be responsible for their inhibitory actions on transformation. (author)

  14. Cytotoxic and genotoxic effects induced by stannous chloride associated to nuclear medicine kits

    International Nuclear Information System (INIS)

    Guedes, Anderson P.; Cardoso, Valbert N.; De Mattos, Jose C.P.; Dantas, Flavio J.S.; Matos, Vanessa C.; Silva, Josiane C.F.; Bezerra, Roberto J.A.C.; Caldeira-de-Araujo, Adriano

    2006-01-01

    At present, more than 75% of routine nuclear medicine diagnostic procedures use technetium-99m ( 99m Tc). The binding between 99m Tc and the drug to obtain Radiopharmaceutical needs a reducing agent, with stannous chloride (SnCl 2 ) being one of the most used. There are controversies about the cytotoxic, genotoxic and mutagenic effects of SnCl 2 in the literature. Thus, the approaches below were used to better understand the biological effects of this salt and its association in nuclear medicine kits [methylenediphosphonate (MDP) bone scintigraphy and diethylenetriaminepentaacetic acid (DTPA) kidney and brain scintigraphy]: (i) bacterial inactivation experiments; (ii) agarose gel electrophoresis of supercoiled and linear plasmid DNA and (iii) bacterial transformation assay. The Escherichia coli strains used here were AB1157 (wild type) and BW9091 (xthA mutant). Data obtained showed that both MDP and SnCl 2 presented a high toxicity, but this was not observed when they were assayed together in the kit, thereby displaying a mutual protect effect. DTPA salt showed a moderate toxicity, and once more, the DTPA kit provided protection, compared to the SnCl 2 effect alone. The results suggest a possible complex formation, either MDP-SnCl 2 or DTPA-SnCl 2 , originating an atoxic compound. On the other hand, SnCl 2 -induced cell inactivation and the decrease in bacterial transformation generated by DTPA found in XthA mutant strain suggest that the lack of this enzyme could be responsible for the effects observed, being necessary to induce DNA damage repair

  15. Some nuclear chemical aspects of medical generator nuclide production at the Los Alamos hot cell facility

    CERN Document Server

    Fassbender, M; Heaton, R C; Jamriska, D J; Kitten, J J; Nortier, F M; Peterson, E J; Phillips, D R; Pitt, L R; Salazar, L L; Valdez, F O; 10.1524/ract.92.4.237.35596

    2004-01-01

    Generator nuclides constitute a convenient tool for applications in nuclear medicine. In this paper, some radiochemical aspects of generator nuclide parents regularly processed at Los Alamos are introduced. The bulk production of the parent nuclides /sup 68/Ge, /sup 82/Sr, /sup 109/Cd and /sup 88/Zr using charged particle beams is discussed. Production nuclear reactions for these radioisotopes, and chemical separation procedures are presented. Experimental processing yields correspond to 80%-98% of the theoretical thick target yield. Reaction cross sections are modeled using the code ALICE-IPPE; it is observed that the model largely disagrees with experimental values for the nuclear processes treated. Radionuclide production batches are prepared 1-6 times yearly for sales. Batch activities range from 40MBq to 75 GBq.

  16. Some nuclear chemical aspects of medical generator nuclide production at the Los Alamos hot cell facility

    International Nuclear Information System (INIS)

    Fassbender, M.; Nortier, F.M.; Phillips, D.R.; Hamilton, V.T.; Heaton, R.C.; Jamriska, D.J.; Kitten, J.J.; Pitt, L.R.; Salazar, L.L.; Valdez, F.O.; Peterson, E.J.

    2004-01-01

    Generator nuclides constitute a convenient tool for applications in nuclear medicine. In this paper, some radiochemical aspects of generator nuclide parents regularly processed at Los Alamos are introduced. The bulk production of the parent nuclides 68 Ge, 82 Sr, 109 Cd and 88 Zr using charged particle beams is discussed. Production nuclear reactions for these radioisotopes, and chemical separation procedures are presented. Experimental processing yields correspond to 80%-98% of the theoretical thick target yield. Reaction cross sections are modeled using the code ALICE-IPPE; it is observed that the model largely disagrees with experimental values for the nuclear processes treated. Radionuclide production batches are prepared 1-6 times yearly for sales. Batch activities range from 40 MBq to 75 GBq. (orig.)

  17. MRI of chemical reactions and processes.

    Science.gov (United States)

    Britton, Melanie M

    2017-08-01

    As magnetic resonance imaging (MRI) can spatially resolve a wealth of molecular information available from nuclear magnetic resonance (NMR), it is able to non-invasively visualise the composition, properties and reactions of a broad range of spatially-heterogeneous molecular systems. Hence, MRI is increasingly finding applications in the study of chemical reactions and processes in a diverse range of environments and technologies. This article will explain the basic principles of MRI and how it can be used to visualise chemical composition and molecular properties, providing an overview of the variety of information available. Examples are drawn from the disciplines of chemistry, chemical engineering, environmental science, physics, electrochemistry and materials science. The review introduces a range of techniques used to produce image contrast, along with the chemical and molecular insight accessible through them. Methods for mapping the distribution of chemical species, using chemical shift imaging or spatially-resolved spectroscopy, are reviewed, as well as methods for visualising physical state, temperature, current density, flow velocities and molecular diffusion. Strategies for imaging materials with low signal intensity, such as those containing gases or low sensitivity nuclei, using compressed sensing, para-hydrogen or polarisation transfer, are discussed. Systems are presented which encapsulate the diversity of chemical and physical parameters observable by MRI, including one- and two-phase flow in porous media, chemical pattern formation, phase transformations and hydrodynamic (fingering) instabilities. Lastly, the emerging area of electrochemical MRI is discussed, with studies presented on the visualisation of electrochemical deposition and dissolution processes during corrosion and the operation of batteries, supercapacitors and fuel cells. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  18. Effects of chemical treatments on hemp fibre structure

    Energy Technology Data Exchange (ETDEWEB)

    Kabir, M.M., E-mail: kabirm@usq.edu.au [Centre of Excellence in Engineered Fibre Composite (CEEFC), Faculty of Engineering and Surveying, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia); Wang, H. [Centre of Excellence in Engineered Fibre Composite (CEEFC), Faculty of Engineering and Surveying, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia); Lau, K.T. [Centre of Excellence in Engineered Fibre Composite (CEEFC), Faculty of Engineering and Surveying, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia); Department of Mechanical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong Special Administrative Region (Hong Kong); Cardona, F. [Centre of Excellence in Engineered Fibre Composite (CEEFC), Faculty of Engineering and Surveying, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia)

    2013-07-01

    In this study, hemp fibres were treated with alkali, acetyl and silane chemicals. Fibre constituents such as cellulose, hemicellulose and lignin constituents were separated from treated fibres. The chemical and thermal influences of these constituents on the treated fibres were examined by using scanning electron microscope (SEM), fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Experimental results revealed that, hemicellulose was degraded faster than that of cellulose and lignin. Cellulose exhibited better thermal stability and lignin was degraded in a wide range of temperatures. The hydrophilic nature of the fibres was predominantly caused by the presence of hemicellulose and then lignin constituents. Hemicellulose and lignin were mostly removed by the alkalisation with higher concentrations of NaOH, followed by acetylation. Silane treatment could not remove the hemicellulose and lignin, rather this treatment facilitated coupling with the fibre constituents.

  19. Effects of chemical treatments on hemp fibre structure

    International Nuclear Information System (INIS)

    Kabir, M.M.; Wang, H.; Lau, K.T.; Cardona, F.

    2013-01-01

    In this study, hemp fibres were treated with alkali, acetyl and silane chemicals. Fibre constituents such as cellulose, hemicellulose and lignin constituents were separated from treated fibres. The chemical and thermal influences of these constituents on the treated fibres were examined by using scanning electron microscope (SEM), fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Experimental results revealed that, hemicellulose was degraded faster than that of cellulose and lignin. Cellulose exhibited better thermal stability and lignin was degraded in a wide range of temperatures. The hydrophilic nature of the fibres was predominantly caused by the presence of hemicellulose and then lignin constituents. Hemicellulose and lignin were mostly removed by the alkalisation with higher concentrations of NaOH, followed by acetylation. Silane treatment could not remove the hemicellulose and lignin, rather this treatment facilitated coupling with the fibre constituents.

  20. chemical determination of burnup ratio in nuclear fuels

    International Nuclear Information System (INIS)

    Guereli, L.

    1997-01-01

    Measurements of the extent of fission are important to determine the irradiation performance of a nuclear fuel. The energy released per unit mass of uranium (burnup) can be determined from measurement of the percent of heavy atoms that have fissioned during irradiation.The preferred method for this determination is choosing a suitable fission monitor (usually ''1''4''8Nd) and its determination after separation from the fuel matrix. In thermal reactor fuels where the only heavy element in the starting material is uranium, uranium depletion can be used for burnup determination. ''2''3''5U depletion method requires measurement of uranium isotopic ratios of both irradiated and unirradiated fuel. Isotopic ratios can be determined by thermal ionization mass spectrometer following separation of uranium from the fuel matrix. Separation procedures include solvent extraction, ion exchange and anion exchange chromatography. Another fission monitor used is ''1''3''9La determination by HPLC. Because La is monoisotopic (''1''3''9La) in the fuel, it can be determined by chemical analysis techniques