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Sample records for chemical effects of nuclear transformations

  1. Chemical effects of nuclear transformations in molybdenum complexes

    International Nuclear Information System (INIS)

    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)

  2. Chemical consequences of nuclear transformations

    International Nuclear Information System (INIS)

    Based on the agreement between theoretical descriptions and observations of initial retention as well as physical studies in solid state, the models that suggest lesser disorder are, at the moment, those that explain better most of the results found in literature. However, as the explanation of the initial retention is only part of the solid state studies, other models must be developed in order to explain the existence and the yield of all observed products as well as the effects of after irradiation treatments, which are responsible for the formation of aditional bonds. (Author)

  3. 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)

    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

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

    International Nuclear Information System (INIS)

    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. Comparative Studies of Chemical Effects following Nuclear Reactions and Transformations on Metal Organic Phenyl Compounds

    International Nuclear Information System (INIS)

    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, γ) 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 Ge68 - tetraphenyl are compared with the results from the (n, γ) -process on Ga-triphenyl and the (n,p) process on Ge-tetra phenyl. Finally, the studies include the β- transition on Ge77-tetraphenyl to As77. 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, γ) 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 Ge68-tetraphenyl. The β- decay on Ge77-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 β- transition. The results are discussed on the basis of theoretical considerations of the amount of kinetic energy transferred to the reacting molecule by the nuclear recoil and the resulting excitation. The hypothesis is

  6. Transformation of Symmetrization Order to Nuclear-Spin Magnetization by Chemical Reaction and Nuclear Magnetic Resonance

    OpenAIRE

    Bowers, C. Russell; Weitekamp, Daniel P.

    1986-01-01

    A method of obtaining very large nuclear-spin polarizations is proposed and illustrated by density-operator calculations. The prediction is that chemical reaction and rf irradiation can convert the scalar parahydrogen state into polarization of order unity on the nuclear spins of the products of molecular-hydrogen addition reactions. A means of extending the resultant sensitivity enhancement to other spins is proposed in which the transfer of order occurs through population differences not as...

  7. Attainable entanglement of unitary transformed thermal states in liquid-state nuclear magnetic resonance with the chemical shift

    CERN Document Server

    Ota, Y; Ohba, I; Yoshida, N; Mikami, Shuji; Ohba, Ichiro; Ota, Yukihiro; Yoshida, Noriyuki

    2006-01-01

    Recently, Yu, Brown, and Chuang [Phys. Rev. A {\\bf 71}, 032341 (2005)] investigated the entanglement attainable from unitary transformed thermal states in liquid-state nuclear magnetic resonance (NMR). Their research gave an insight into the role of the entanglement in a liquid-state NMR quantum computer. Moreover, they attempted to reveal the role of mixed-state entanglement in quantum computing. However, they assumed that the Zeeman energy of each nuclear spin which corresponds to a qubit takes a common value for all; there is no chemical shift. In this paper, we research a model with the chemical shifts and analytically derive the physical parameter region where unitary transformed thermal states are entangled, by the positive partial transposition (PPT) criterion with respect to any bipartition. We examine the effect of the chemical shifts on the boundary between the separability and the nonseparability, and find it is negligible.

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

    International Nuclear Information System (INIS)

    Chemical effects associated to nuclear transformation 37Cl (n, γ) 38Cl or 127I (n, γ) 128I 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

  9. Chemical modification of neoplastic cell transformation by heavy ion radiation

    International Nuclear Information System (INIS)

    Quantitative data on chemical modification of neoplastic cell transformation by heavy-ion radiation was obtained using in-vitro cell transformation technique. The specific aims were 1) to test the potential effects of various chemicals on the expression of cell transformation, and 2) to systematically collect information on the mechanisms of expression and progression of cell transformation by ionizing radiation. Recent experimental studies with DMSO, 5-azacytidine, and dexamethasone suggest that DMSO can effectively suppress the neoplastic cell transformation by high-LET radiation and that some nonmutagenic changes in DNA may be important in modifying the expression, and progression of radiation-induced cell transformation

  10. Analysis of current state of transformer equipment, its role and place in affording safety, increasing power- and ecological effectiveness operation of units of nuclear power stations of Ukraine

    International Nuclear Information System (INIS)

    Analysis of technical state, life service and reliability of modern transformer equipment of power generating units of nuclear power stations (NPS) was conducted. Cause-and-effect factors of pre-emergency and emergency faults of transformers have been analyzed. Technical offers aimed at improvement of efficiency and reliability parameters of transformer equipment operation on NPS units were developed.

  11. 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...

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

    International Nuclear Information System (INIS)

    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

  13. 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.

  14. 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.

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

    International Nuclear Information System (INIS)

    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

  16. Nuclear transformations studies in selenium isotopes

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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)

  18. MICROBIAL TRANSFORMATIONS OF RADIONUCLIDES RELEASED FROM NUCLEAR FUEL REPROCESSING PLANTS.

    Energy Technology Data Exchange (ETDEWEB)

    FRANCIS,A.J.

    2006-10-18

    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.

  19. Chemical oxidation of unsymmetrical dimethylhydrazine transformation products in water

    OpenAIRE

    Madi Abilev; Bulat Kenessov; Svetlana Batyrbekova; Tim Grotenhuis

    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 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 o...

  20. 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

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Suk Bon; Jung, Chong Hun; Kim, Chang Ki; Choi, Byung Seon; Lee, Kune Woo; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    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

  3. Nuclear, chemical, and physical characterization of nuclear materials

    International Nuclear Information System (INIS)

    The goal of nuclear forensics is to establish an unambiguous link between illicitly trafficked nuclear material and its origin. The Los Alamos National Laboratory (LANL) Nuclear Materials Signatures Program has implemented a graded 'conduct of operations' type analysis flow path approach for determining the key nuclear, chemical, and physical signatures needed to identify the manufacturing process, intended use, and origin of interdicted nuclear material. This analysis flow path includes both destructive and non-destructive characterization techniques and has been exercized against different nuclear materials from LANL's special nuclear materials archive. Results obtained from the case study will be presented to highlight analytical techniques that offer the critical attribution information. (author)

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  6. 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...

  7. Use of the Chemical Transformation Simulator as a Parameterization Tool for Modeling the Environmental Fate of Organic Chemicals and their Transformation Products

    Science.gov (United States)

    A Chemical Transformation Simulator is a web-based system for predicting transformation pathways and physicochemical properties of organic chemicals. Role in Environmental Modeling • Screening tool for identifying likely transformation products in the environment • Parameteri...

  8. Effects of citrate on the dissolution and transformation of biotite, analyzed by chemical and atomic force microscopy

    International Nuclear Information System (INIS)

    Highlights: • Protons have a dominant role in the dissolution process of biotite (0 0 1) surface. • Organic (carboxyl) acts as a catalyst under weakly acidic soil condition. • Biotite dissolution starts from defect sites and develops along [h k 0] direction. • Secondary coating on (0 0 1) surface would hinder the etch pits formation. - Abstract: The aim of this study was to investigate the dissolution and transformation characteristics of phyllosilicate under low molecular weight organic acids in the farmland environment (pH 4.0–8.0). Changes of dissolution and morphology of biotite were evaluated using chemical extraction experiments and in situ/ex situ atomic force microscopy (AFM) with fluids of citric acid (CA) solution at pH 4.0, 6.0, and 8.0. Results of extracting experiments show that CA solutions contributed to the release rate of potassium (K), silicon (Si), and aluminum (Al) from biotite relative to a control aqueous solution. In situ AFM observations indicate that the dissolution of biotite from the biotite (0 0 1) surface occurred on the terrace, segment, and fringe of pits, while new etch pits did not readily form on biotite (0 0 1) surfaces in aqueous solutions. However, dissolution rates of terraces can be greatly accelerated with the help of citrate. In pH 4.0 CA solution, 70 min dissolution reactions of biotite (0 0 1) surfaces result in more etch pits than in pH 6.0 and 8.0 solutions. In addition, the transformation of biotite occurred simultaneously with the dissolution process. Secondary coating was observed on the biotite (0 0 1) surface after 140 h of immersion in a weak acid environment. Thus, the protons have a dominant role in the dissolution process of biotite with organic (carboxyl) acting as a catalyst under acidic condition. Based on the theory of interactions on a water–mineral interface in a weak acid environment, dissolution of biotite starts from defect/kink sites on the surface, one layer by one layer, and develops

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

    International Nuclear Information System (INIS)

    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

  10. Quantum chemical studies of epoxide-transforming enzymes

    OpenAIRE

    Hopmann, Kathrin H.

    2007-01-01

    Density functional theory is employed to study the reaction mechanisms of different epoxide-transforming enzymes. Calculations are based on quantum chemical active site models, which are build from X-ray crystal structures. The models are used to study conversion of various epoxides into their corresponding diols or substituted alcohols. Epoxide-transforming enzymes from three different families are studied. The human soluble epoxide hydrolase (sEH) belongs to the α/β-hydrolase fold family. s...

  11. Effects of Nuclear Weapons.

    Science.gov (United States)

    Sartori, Leo

    1983-01-01

    Fundamental principles governing nuclear explosions and their effects are discussed, including three components of a nuclear explosion (thermal radiation, shock wave, nuclear radiation). Describes how effects of these components depend on the weapon's yield, its height of burst, and distance of detonation point. Includes effects of three…

  12. Chemical reprocessing of spent nuclear fuels

    International Nuclear Information System (INIS)

    The reprocessing of nuclear fuels from atomic power stations has a twofold goal. On the one hand it is serving for fuel supply by recovering the fissile materials which have not been consumed or which have been freshly generated in the reactor. On the other hand the radioactive waste products from nuclear power generation are pretreated for long-term safe disposal. The core element of the chemical processing is the PUREX Process, a counter-current solvent extraction procedure using tributyl phosphate (TBP) as the solvent for uranium and plutonium. The chemical basis and the technological performance of the process are discussed. (orig.)

  13. Nuclear war: Short-term chemical and radiative effects of stratospheric injections

    International Nuclear Information System (INIS)

    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. Only recently has the potential reduction in stratospheric ozone been calculated as a function of latitude using a two-dimensional model where effects are averaged over latitude bands. The possibility exists that on a subcontinental scale the ozone depletion might be considerably greater than the hemispheric-average or zonal-average value. The results presented here are the first assessment of the potential reduction in total ozone on a sub-continental scale. The purpose of this study 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

  14. 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.

  15. 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.

  16. Neoplastic transformation of human diploid fibroblast cells by chemical carcinogens

    Science.gov (United States)

    Kakunaga, Takeo

    1978-01-01

    Cultured fibroblast cells derived from a skin biopsy sample taken from normal human adult were exposed to a potent carcinogen, 4-nitroquinoline 1-oxide. Alterations of cell growth pattern such as higher density and piling up of cells were noticed in some fractions of cultures that were successively subcultured after nitroquinoline oxide treatment. Morphologically altered cells retained this growth pattern and became established lines of transformed cells without showing the limited life-span characteristic of normal cells in culture. The transformed cells showed a higher saturation density and the ability to grow in soft agar, properties that are usually correlated with neoplastic transformation of cells in culture. Selection of preexisting transformed human cells as a mechanism of this observed transformation seemed unlikely because clones of these normal cells could also be used to assess the transforming effect of nitroquinoline oxide. Preliminary results suggest that numerous cell divisions were required for the development of the transformation after nitroquinoline oxide treatment of these human cells. When the transformed cell lines were injected subcutaneously into nude (athymic) mice, solid tumors were produced at the site of inoculation. Treatment with N-methyl-N′-nitro-N-nitrosoguanidine also induced cell transformation, in a manner similar to treatment with nitroquinoline oxide. However, transformation was not induced with (i) 4-aminoquinoline 1-oxide (a noncarcinogenic derivative of 4-nitroquinoline 1-oxide), (ii) 3-methylcholanthrene (a carcinogen that cannot be metabolically activated by the target cells employed), or (iii) the solvent dimethyl sulfoxide. Images PMID:418410

  17. The effect of chemical transformations on terrestrial element cycling and food-chain transport of technetium-99

    International Nuclear Information System (INIS)

    The environmental behavior of technetium-99 (99Tc) is dominated by oxidation-reduction reactions and, for valence states, by complex formation with organics. Pertechnetate anion is the migratory form found in shallow groundwaters adjacent to radioactive waste disposal sites, but transformations in the terrestrial environment result in a behavior that is very different than that expected of a soluble anion. Technetium bioaccumulates in the transfer from soil to plant, but Tc incorporated in plants is less readily absorbed from the gastrointestinal tract of animals than pertechnetate. In soil, there is a dynamic equilibrium between pertechnetate, the form available for plant uptake, and reduced/complexed forms. Following uptake by forest trees, pertechnetate is incorporated in the structural components of leaf cell walls. An ecosystem model has been developed to explain the uptake, recycling, transformation, and controlling variables for the mobility of 99Tc in humid deciduous forests adjacent to radioactive waste disposal areas

  18. Heterogeneous photocatalysis of moxifloxacin in water: chemical transformation and ecotoxicity.

    Science.gov (United States)

    Van Doorslaer, Xander; Haylamicheal, Israel Deneke; Dewulf, Jo; Van Langenhove, Herman; Janssen, Colin R; Demeestere, Kristof

    2015-01-01

    This work provides new insights on the impact of TiO2/UV catalyzed chemical transformation of moxifloxacin on ecotoxicity effects towards the green alga Pseudokirchneriella subcapitata. The moxifloxacin median effect concentration (EC-50=0.78 [0.56, 1.09] mg L(-1)), determined in accordance to the OECD 72-h growth inhibition test guideline, was 7 times lower than that of the older and widely used fluoroquinolone ciprofloxacin (EC-50=5.57 [4.86, 6.38] mg L(-1)). Applying heterogeneous photocatalysis as an advanced oxidation technique to degrade moxifloxacin in aqueous solution decreased the average growth inhibition from 72% to 14% after 150 min of treatment. No significant carbon mineralization was observed and liquid chromatography mass spectrometry analysis revealed the formation of 13 degradation products for which a chemical structure could be proposed based on accurate mass determination. Combined chemical and ecotoxicological analysis showed that as long as moxifloxacin is present in the reaction solution, it is the main compound affecting algal growth inhibition. However, also the contribution of the degradation products to the observed ecotoxicity cannot be neglected. Photocatalytically induced modifications of moxifloxacin mainly occur at the diazobicyclo-substituent as ring opening, oxidation into carbonyl groups, and hydroxylation. This results into the formation of more hydrophilic compounds with a decreased biological activity compared with moxifloxacin. The change in lipophilicity, and possibly a modified acid-base speciation, most probably also affect the cell membrane permeation of the degradation products, which might be another factor explaining the observed lower residual ecotoxicity of the photocatalytically treated reaction solutions. PMID:24735961

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

    International Nuclear Information System (INIS)

    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)

  20. Evolution of nuclear chemical industry in France

    International Nuclear Information System (INIS)

    The present characteristics can be summarized in one word: expansion. Impelled by the CEA, but also by such organisations as the Electricite de France and the Merchant Marine, the French nuclear effort for the years 1957-1961 reaches about 600 thousand millions francs; over half this sum will be spent by chemical industry on research, pilot installations, construction of plants and delivery. The aim is to work efficiently, quickly and profitably. This is achieved through close collaboration between the big state organisations and private industry. It is chiefly along the following lines that this large scale effort is carried on: - thorough chemical treatment of increasing tonnages of ores from the French Union, with the aim of producing pure, plentiful and cheap uranium. - careful preparation of nuclear fuels, economical and perfectly adapted to the various types of reactor in operation or under construction. - Further treatment of irradiated fuels to extract the plutonium completely, as well as the uranium and certain fission products. industrial manufacture of material of nuclear purity or corrosion resistant required by the technology of energy producing or research reactors. - Supply to the many foreign or French users of isotopes and radioactive tracers required by medicine, industry and agriculture in ever-increasing numbers. - Meticulous chemical treatment of gaseous or liquid effluent in strictly controlled stations in order that reactors and their annexes will be perfectly safe to use. This account shows the great extent of the effort laid out by a young, energetic chemical industry in full swing. Having made sure of its techniques and set up numerous installations it is fully in a position to confront the French atomic programme. In addition it is able and anxious to associate with the developments of foreign atomic industry, especially EURATOM and Eurochemic. (author)

  1. Chemical aspects of nuclear waste treatment

    International Nuclear Information System (INIS)

    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

  2. Gastroprotective effects of new diterpenoid derivatives from Azorella cuatrecasasii Mathias & Constance obtained using a β-cyclodextrin complex with microbial and chemical transformations.

    Science.gov (United States)

    Sepúlveda, Beatriz; Quispe, Cristina; Simirgiotis, Mario; García-Beltrán, Olimpo; Areche, Carlos

    2016-07-15

    Mulinane diterpenoids isolated from Azorella species have displayed gastroprotective effects in animal models. In this study we have transformed the main constituent, mulin-11,13-dien-20 oic acid from this plant using the filamentous fungus Mucor plumbeus and a β-cyclodextrin inclusion complex and we have obtained two main products with good yields (33% and 15% for compound 4 and 5, respectively) for further preparation of semisynthetic derivatives to evaluate their gastroprotective effects. In addition, one of the compounds isolated from Azorella cuatrecasasii was new (9-epi-13α-hydroxymulinene 1). Six new derivatives 4a-4c and 5a-5c were then prepared by simple chemical transformations. The structures of all compounds were elucidated by spectroscopic means based on 1D and 2D-NMR techniques. Some 8 diterpenes were evaluated for their gastroprotective effects in the ethanol/HCl-induced ulcer model in mice at 20mg/kg. The highest gastroprotective activity was shown by 7α,16-dihydroxymulin-11,13-dien-20-oic acid 5, which was higher than the reference drug lansoprazole, while 16-hydroxymulin-11,13-dien-20-oic acid 4 was as active as lansoprazole. PMID:27262597

  3. Effect of annealing temperature on the crystalline quality and phase transformation of chemically deposited CdSe films

    International Nuclear Information System (INIS)

    Polycrystalline CdSe thin films were grown on glass substrates by chemical bath deposition at 50 C. The samples were annealed in air atmosphere at different temperatures and characterized by X-ray diffraction and Raman spectroscopy. It was found that the as-grown films have cubic structure. These samples maintain their cubic structure for annealing temperatures between 60 C and 300 C. For annealing temperatures higher than 300 C we obtain a mixture of cubic and hexagonal phases. The analysis made by X-ray diffraction and Raman dispersion show that the samples annealed at temperatures under the phase-transition temperature increase their crystalline quality. In order to determinate the temperature for the complete transition of the cubic phase, we used the precipitated material obtained during the grown of the CdSe films. This material was annealed on air atmosphere between 300 C and 500 C with 50 intervals. The samples were measured by X-ray diffraction. The samples maintained the cubic structure if the annealing temperature is under 300 C. For temperatures between 300 C and 450 C we found a mixture of cubic and hexagonal phase. For an annealing temperature of 500 C we obtain only the hexagonal phase. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Effect of glucose and pyruvate on nuclear and cytoplasmic maturation of porcine oocytes in a chemically defined medium

    OpenAIRE

    FUNAHASHI, Hiroaki; Koike, Takayuki; Sakai, Ryoko

    2008-01-01

    The objective was to examine potential roles of glucose and pyruvate in nuclear and cytoplasmic maturation of porcine oocytes. Oocyte-cumulus complexes (OCC), derived from 3 to 6 mm follicles, were cultured in a chemically defined medium (pyruvate-free mNCSU37-PVA), with or without 5.55 mM glucose, during in vitro maturation (IVM); in the absence of glucose, germinal vesicle breakdown (GVBD) and nuclear maturation were prevented (P < 0.05). Subsequently, OCC were cultured for IVM in glucose-c...

  5. 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

  6. Chemical contamination and transformation of soils in hydrocarbon production regions

    Science.gov (United States)

    Zamotaev, I. V.; Ivanov, I. V.; Mikheev, P. V.; Nikonova, A. N.

    2015-12-01

    The current concepts of soil pollution and transformation in the regions of hydrocarbon production have been reviewed. The development of an oil field creates extreme conditions for pedogenesis. Tendencies in the radial migration, spatial distribution, metabolism, and accumulation of pollutants (oil, oil products, and attendant heavy metals) in soils of different bioclimatic zones have been analyzed. The radial and lateral mobility of pollution halos is a universal tendency in the technogenic transformation of soils and soil cover in the regions of hydrocarbon production. The biodegradation time of different hydrocarbon compounds strongly varies under different landscape conditions, from several months to several tens of years. The transformation of original (mineral and organic) soils to their technogenic modifications (mechanically disturbed, chemically contaminated, and chemo soils and chemozems) occurs in the impact zone of technogenic hydrocarbon fluxes under any physiographical conditions. The integrated use of the existing methods for the determination of the total content and qualitative composition of bituminous substances and polyaromatic hydrocarbons in combination with the chromatographic determination of normal alkanes and hydrocarbon gases, as well as innovative methods of studies, allows revealing new processes and genetic relationships in soils and studying the functioning of soils and soil cover. The study of the hydrocarbon contamination of soils is important for development of restoration measures and lays the groundwork for the ecological and hygienic regulation based on the zonation of soil and landscape resistance to different pollutants.

  7. Development of multicomponent hybrid density functional theory with polarizable continuum model for the analysis of nuclear quantum effect and solvent effect on NMR chemical shift

    International Nuclear Information System (INIS)

    We have developed the multicomponent hybrid density functional theory [MC-(HF+DFT)] method with polarizable continuum model (PCM) for the analysis of molecular properties including both nuclear quantum effect and solvent effect. The chemical shifts and H/D isotope shifts of the picolinic acid N-oxide (PANO) molecule in chloroform and acetonitrile solvents are applied by B3LYP electron exchange-correlation functional for our MC-(HF+DFT) method with PCM (MC-B3LYP/PCM). Our MC-B3LYP/PCM results for PANO are in reasonable agreement with the corresponding experimental chemical shifts and isotope shifts. We further investigated the applicability of our method for acetylacetone in several solvents

  8. Chemical effects of radiation

    International Nuclear Information System (INIS)

    Ionizing radiations initiate chemical changes in materials because of the high energy of their quanta. In water, highly reactive free radicals are produced which can initiate secondary changes of solutes, and in chemical of biological molecules in contact with the water. Free radicals can also be directly produced in irradiated medical products. Their fate can be identified and the molecular basis of radiation inactivation clarified. Methods have now been developed to protect and minimise such radiation damage. (author)

  9. Effect of nuclear spin on chemical reactions and internal molecular rotation

    International Nuclear Information System (INIS)

    Part I of this dissertation is a study of the magnetic isotope effect, and results are presented for the separation of 13C and 12C isotopes. Two models are included in the theoretical treatment of the effect. In the first model the spin states evolve quantum mechanically, and geminate recombination is calculated by numerically integrating the collision probability times the probability the radical pair is in a singlet state. In the second model the intersystem crossing is treated via first-order rate constants which are average values of the hyperfine couplings. Using these rate constants and hydrodynamic diffusion equations, an analytical solution, which accounts for all collisions, is obtained for the geminate recombination. The two reactions studied are photolysis of benzophenone and toluene and the photolytic decomposition of dibenzylketone (1,3-diphenyl-2-propanone). No magnetic isotope effect was observed in the benzophenone reaction. 13C enrichment was observed for the dibenzylketone reaction, and this enrichment was substantially enhanced at intermediate viscosities and low temperatures. Part II of this dissertation is a presentation of theory and results for the use of Zeeman spin-lattice relaxation as a probe of methyl group rotation in the solid state. Experimental results are presented for the time and angular dependences of rotational polarization, the methyl group magnetic moment, and methyl-methyl steric interactions. The compounds studied are 2,6-dimethylphenol, methyl iodide, 1,4,5,8-tetramethylanthracene, 1,4,5,8-tetramethylnaphthalene, 1,2,4,5-tetramethylbenzene, and 2,3-dimethylmaleicanhydride

  10. Selected Chemical Aspects of Nuclear Power Development

    OpenAIRE

    Chmielewski, Andrzej G.; Marcin Brykala; Tomasz Smolinski

    2012-01-01

    The Fukushima nuclear power plant (NPP) accident consequences are a new challenge for nuclear power development; however the sequence of the event has illustrated importance of radiation- and radiochemistry processes on the safe operation and shut down of nuclear reactor and decontamination of formed liquid and solid wastes. A chemistry program is essential for the safe operation of a nuclear power plant. It ensures the integrity, reliability and availability of the main plant structures, sys...

  11. Chemicals as the Sole Transformers of Cell Fate

    Science.gov (United States)

    Ebrahimi, Behnam

    2016-01-01

    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. PMID:27426081

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

    International Nuclear Information System (INIS)

    Two of the primary criteria for the acceptability of nuclear waste glasses are their durability, i.e. chemical resistance to aqueous attack for 104 to 105 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

  13. Effect of gas flow rates on the anatase-rutile transformation temperature of nanocrystalline TiO2 synthesised by chemical vapour synthesis.

    Science.gov (United States)

    Ahmad, Md Imteyaz; Bhattacharya, S S; Fasel, Claudia; Hahn, Horst

    2009-09-01

    Of the three crystallographic allotropes of nanocrystalline titania (rutile, anatase and brookite), anatase exhibits the greatest potential for a variety of applications, especially in the area of catalysis and sensors. However, with rutile being thermodynamically the most stable phase, anatase tends to transform into rutile on heating to temperatures in the range of 500 degrees C to 700 degrees C. Efforts made to stabilize the anatase phase at higher temperatures by doping with metal oxides suffer from the problems of having a large amorphous content on synthesis as well as the formation of secondary impurity phases on doping. Recent studies have suggested that the as-synthesised phase composition, crystallite size, initial surface area and processing conditions greatly influence the anatase to rutile transformation temperature. In this study nanocrystalline titania was synthesised in the anatase form bya chemical vapour synthesis (CVS) method using titanium tetra iso-propoxide (TTIP) as a precursor under varying flow rates of oxygen and helium. The anatase to rutile transformation was studied using high temperature X-ray diffraction (HTXRD) and simultaneous thermogravimetric analysis (STA), followed by transmission electron microscopy (TEM). It was demonstrated that the anatase-rutile transformation temperatures were dependent on the oxygen to helium flow rate ratio during CVS and the results are presented and discussed. PMID:19928267

  14. KINETICS OF CHEMICAL TRANSFORMATIONS OF HYDROCARBONS WORKING LIQUID FH-51 AT OPERATING AIRCRAFT

    OpenAIRE

    Кузнєцова, О.; Національний авіаційний університет; Нетреба, Ж.; Національний авіаційний університет

    2013-01-01

    Today the French hydraulic liquid «Hydronicoil» FH-51 is used in aircraft hydrosystems of Ukraine airlines.During aircraft exploitation under the action of external factors there are chemical transformations in molecules of liquid hydrocarbons. Research on kinetics of chemical transformations of hydrocarbons of working liquidFH-51 is carried out. The model of the noted chemical transformations, which provide achievement of necessary quality level of the liquid and aircraft reliability, is fou...

  15. Denoising of Nuclear Medicine images using Wavelet Transform

    International Nuclear Information System (INIS)

    Diagnosis using images is widely used in Nuclear Medicine. However, in the case of planar images some problems can appear related to low detectability of small lesions, due to noise contamination. This phenomenon is emphasized because of the impossibility of increasing the radiopharmaceutical dose or the exposure time above the established levels. An algorithm to reduce the random Gaussian noise in planar images using the Wavelet Transform is described in this paper. Results are compared among a set of filters designed by this procedure, in order to select those that offer the best images considering the evaluation of the image quality through quantitative metrics (au)

  16. Radiological Effects of Nuclear War.

    Science.gov (United States)

    Shapiro, Charles S.

    1988-01-01

    Described are the global effects of nuclear war. Discussed are radiation dosages, limited nuclear attacks, strategic arms reductions, and other results reported at the workshop on nuclear war issues in Moscow in March 1988. (CW)

  17. Chemically and temperature-induced phase transformations of metal vanadates

    Science.gov (United States)

    Patridge, Christopher James

    different individual beta'-Cu xV2O5 nanowires vary widely. Using scanning transmission X-ray microspectroscopy of individual beta'-CuxV2O 5 nanowires, correlations appear to exist between MIT characteristics and the markedly different orbital hybridization of vanadium and oxygen at the O K and V L absorption edges. These comprehensive nanostructure studies hint at the possibility of approaching the incredibly important realm of single-domain measurements which are needed to understand and exploit the intrinsic physical properties of materials. In addition to the bronze MIT studies, the classical MIT material vanadium dioxide, VO2, also shows new properties when scaling down to nanoscale dimensions as well as incorporation of substitutional dopants such as tungsten. X-ray absorption spectroscopy of the dopant local structure suggests an increased symmetry and depairing of V4+-V 4+, which is critical for transition to the lower temperature insulating phase thereby super-cooling the metallic phase to temperatures as low as 254 K. Mechanistic insight and structural changes associated with the intercalation of Li+ are key aspects in understanding and designing useful secondary Li ion batteries. In similarity to the MxV2O 5 studies, another metal vanadate, Ag2VO2PO 4, undergoes phase transformations due to introduction of Li and the vacancy of Ag ions. Employing a comprehensive study on Ag2VO 2PO4 using X-ray absorption spectroscopy, information about chemical state changes and rehybridization of frontier orbitals allows for a more precise understanding of how the material discharges, what, if any, intermediate phases exist during the process, and provides evidence for the posited structural stability at high depths of discharge.

  18. Psychological effects of nuclear warfare

    International Nuclear Information System (INIS)

    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

  19. 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

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

    International Nuclear Information System (INIS)

    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

  1. The study of the determination of subjective vibration velocity rating of main transformer under operating in nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Wook Ryun; Lee, Jun Shin; Kim, Byong Han; Lee, Sang Kil; Lee, Sang Guk [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    Main transformer's integrity assessment in nuclear power plant is estimated by the electrical test of electrical core and wire and the chemical analysis of insulating oil. Mechanical test or analysis has not been so far. So this study makes it with the vibration velocity rating. The vibration velocity ratings in main transformer that is based on the real data from vibration velocity measurement under operating and other machinery vibration code such as ISO code is renewed.

  2. Effect of Stress on Transformer Insulation

    Directory of Open Access Journals (Sweden)

    Kapil Gandhi

    2012-06-01

    Full Text Available Power transformers use Kraft paper as insulation in the electrical windings present in the core, which is immersed in oil. In service, the temperature of the windings of core will go to 750C to 850C. If the transformer is over loaded, then the temperature can exceed upto 100°C causing the cellulose chains in the paper to cleave at an accelerated rate, which results in the degradation of mechanical strength and performance of the insulation. The Degree of Polymerization (DP will also decrease. If proper action will not take, this can lead to failure of the transformer and disruption to electricity supply and large economic losses to the operating utility. Transformer condition should be maintained because of its importance to electricity network. The life of transformer depends on the life of the oil impregnated paper insulation system to greater extent. Degradation of the cellulose insulation is an irreversible process. After thermal degradation of the paper winding, Furfuraldehyde (FFA is the chemical compound, which is released into the oil from paper. The concentration of FFA has been directly related to the condition of the paper insulation. In the present paper an experimental investigation has been made to evaluate the degradation of transformer oil contaminated by nano-particles of pine wood under accelerated thermal and electrical stress and results are correlated with breakdown strength, density & interfacial tension of the pure oil. The contaminated oil samples are tested at electric stress of 2.0 kV, 3.0 kV, 4.0 kV & 5.0 kV for 24, 48, 72 & 96 hours simultaneously.

  3. Investigation into radiation-chemical transformations of polyamide P-54

    International Nuclear Information System (INIS)

    Investigation results of alcohol-soluble polyamide P-54 radiolysis by different physicochemical methods are presented. It has been established that under the effect of γ-radiation certain processes take place in polyamide, which are connected with branching, structurization and destruction of macromolecules. Radiation-chemical yields of gaseous products during irradiation in the air and in vacuum at irradiation temperatures from 273 to 393 K are calculated. The ratio of the rates of lacing and destruction processes is found and radiation yields of the processes are determined. Under irradiation in the air at temperatures >333 K chain oxidation of P-54 takes place and the growth of pe-- roxide compounds with 8 molecules/100 eV at 298 K up to 135 mole-- cules/100 eV at irradiation temperature 373 K testifies to the fact

  4. Neutron albedo effects of underground nuclear explosion

    International Nuclear Information System (INIS)

    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)

  5. The effects of chemical and heat maceration techniques on the recovery of nuclear and mitochondrial DNA from bone.

    Science.gov (United States)

    Steadman, Dawnie Wolfe; DiAntonio, Lisa L; Wilson, Jeremy J; Sheridan, Kevin E; Tammariello, Steven P

    2006-01-01

    Forensic anthropologists use a number of maceration techniques to facilitate skeletal analysis of personal identity and trauma, but they may unwittingly eliminate valuable DNA evidence in the process. This study evaluated the effect of 10 maceration methods on gross bone structure and the preservation of DNA in ribs of 12 pigs (Sus scrofa). A scoring system was applied to evaluate the ease of maceration and resulting bone quality while DNA purity was quantified by optical densitometry analysis, followed by polymerase chain reaction (PCR) amplification of three mitochondrial and three nuclear loci. The results demonstrated that while mitochondrial DNA could be amplified for all experiments, cleaning treatments using bleach, hydrogen peroxide, ethylenediaminetetraacetic acid/papain, room temperature water and detergent/sodium carbonate followed by degreasing had low DNA concentrations and failed to generate nuclear PCR products. In general, treatments performed at high temperatures (90 degrees C or above) for short durations performed best. This study shows that traditionally "conservative" maceration techniques are not necessarily the best methods to yield DNA from skeletal tissue. PMID:16423217

  6. MICROBIAL TRANSFORMATION OF SELECTED ORGANIC CHEMICALS IN NATURAL AQUATIC SYSTEMS

    Science.gov (United States)

    A method for describing the microbial degradation of xenobiotics through the use of a second-order reaction equation was tested in several water bodies in the United States and Russia. he experiment was aimed at studying the microbial transformation of a herbicide widely used in ...

  7. Microbial transformation of highly persistent chlorinated pesticides and industrial chemicals.

    NARCIS (Netherlands)

    Middeldorp, P.J.M.

    1997-01-01

    Organic pollutants can be transformed, both in unsaturated and saturated areas of the soil, by means of biologically mediated reactions. The potential of soil microorganisms to clean up polluted soils is enormous. However, soil systems are highly heterogeneous with respect to the spatial distributio

  8. Nuclear fuel cycle programs of Argonne's Chemical Engineering Division

    International Nuclear Information System (INIS)

    Argonne National Laboratory's Chemical Engineering Division is actively involved in the research, development and demonstration of nuclear fuel cycle technologies for the United States Department of Energy Advanced Fuel Cycle Initiative, Generation IV, and Yucca Mountain programs. This paper summarizes current technology development initiatives within the Division that address the needs of the United States' advanced nuclear energy programs. (authors)

  9. Chemical aspects of nuclear fusion: New developments

    International Nuclear Information System (INIS)

    Managing thermally controlled nuclear fusion will certainly be regarded one day as one of the most successful accomplishments in nuclear physics. At the same time, however, it will represent a technical achievement unparalleled in the history of science and engineering. This in turn would mean, in retrospect, that decisive contributions had to come from a number of disciplines as diverse as materials and engineering sciences and classical chemistry, and that the same collaboration will have to continue in the future in order to reach the ultimate goal, to construct a reactor capable of producing energy from almost inexhaustible source materials (fuels), such as deuterium and lithium. What is the chemist's role in this development. Similarly as in the development of fission reactors, i.e., the nuclear power plants currently in operation, chemists will have to ensure the existence of a reliable fuel cycle - starting from the availability, storage and reprocessing of the fuel through to the provision for safe storage of the waste. In this review article an attempt will be made to outline the problems associated with these tasks and the approaches to be made by the chemist in solving them. (orig.)

  10. A new method for the study of the formation and transformation of calcium phosphate precipitates: effects of several chemical agents and Chinese folk medicines.

    Science.gov (United States)

    Hidaka, S; Abe, K; Liu, S Y

    1991-01-01

    A simple method of assaying the formation of amorphous calcium phosphate and its transformation to hydroxyapatite using a conventional pH meter and recorder is described. Its validity was confirmed by direct assay of calcium consumption with atomic absorption spectrophotometry. The method was used to study substances which influence the formation of amorphous calcium phosphate and its transformation to hydroxyapatite, such as albumin, casein, chondroitin sulphate, phospholipid, ATP, Mg2+, Sr2+, pyrophosphate and several Chinese folk medicines. PMID:1849399

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

    International Nuclear Information System (INIS)

    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

  12. Microbial transformation of highly persistent chlorinated pesticides and industrial chemicals.

    OpenAIRE

    Middeldorp, P.J.M.

    1997-01-01

    Organic pollutants can be transformed, both in unsaturated and saturated areas of the soil, by means of biologically mediated reactions. The potential of soil microorganisms to clean up polluted soils is enormous. However, soil systems are highly heterogeneous with respect to the spatial distribution of substrates, nutrients and microorganisms, and also with respect to various phases and interfaces (e.g. water, air, minerals, organic matter). To come to the development of appropriate soil bio...

  13. Nuclear chemical mining of primary copper sulfides

    International Nuclear Information System (INIS)

    A contained nuclear explosion is proposed to produce a chimney of broken ore well below the water table. After the chimney is filled with water and reaches hydrostatic equilibrium, O, under pressure, is introduced near the bottom of the mass of broken rock. The increase in solubility of O at high hydrostatic pressure is sufficient to initiate the oxidation of the primary sulphides, chalcopyrite and pyrite. The oxidation and dissolution of these sulphides produces enough heat to increase the temperature of the ore and water in the chimney as much as 100 to 1500C. The rate of dissolution of chalcopyrite exposed to O-saturated solutions becomes so rapid under these conditions that the rate of Cu extraction becomes limited to the accessibility of chalcopyrite to the solutions. Means of solution control and distribution of O in the chimney have been examined in some detail. A calculational model utilizing experimentally determined solubility rates is utilized to estimate the temperature rise in the chimney and the rate of Cu recovery as a function of initial temperature, sulphide content of ore and size of ore particles. It is concluded that the high pressure and high temperature obtainable in a large ore mass broken by nuclear explosives promise the rapid and economic recovery of minerals not considered soluble by conventional in situ leaching methods. The method should be broadly applicable to the kinds of deep deposits that must be depended on for future production and with minimum disruption of the environment. (U.S.)

  14. Nuclear and chemical properties of the transactinide elements

    International Nuclear Information System (INIS)

    Transactinide elements, whose atomic number larger than 104 and classified as 6d-transition elements in the periodic table, have seldom been studied of the chemical nature in spite of much interest in the possible relativistic effects of these superheavy nuclides. This report briefly reviews recent topics in the advancement for the superheavy (Z > 104) nuclide synthesis by means of cold fusion with varying combinations of incident and target atoms using ion accelerators, for example, at GSI, Darmstadt, and at JINR, Dubna. It also reviews recent progress in their nuclear and chemical properties studied by a world-wide cooperative research group working at GSI, Mainz University, Bern University, PSI, Uppsala University, Dubna and LBL groups into which JAERI group has joined since 1998. Moreover, expectation is stated for the successful synthesis of superheavy elements on employment of radioactive beams consisting of neutron-excess nuclides. (Ohno, S.)

  15. Fourier transform microscope of the direct observation for nuclear emulsion

    International Nuclear Information System (INIS)

    'The fourier transfom (FT) microscope of the direct observation' for tracks of charged particles in the nuclear emulsion is described. The working flow charts are given of the digital processing of the signals from the array of photodetectors disposed just behind the narrow transmitting slit in the FT plane. The general theory of this new device is presented. The net effect of the proposed processing algorithms is discussed. It is shown experimentally that with such a system we can detect the particle tracks with linear density of 40 silver grains per 100 μm with initial signal-to-noise ratio 1:3. The recommendations for the searching for the particle tracks of low ionization level in the nuclear emulsion by means of the FT microscope of the direct observation are described. 9 refs.; 15 figs.; 1 tab

  16. The Characteristics of an Effective Nuclear Regulator

    International Nuclear Information System (INIS)

    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)

  17. Fourier transform-infrared studies on the effects of salt and drought stress on the chemical composition and pro-tein conformation changes in Arabidopsis leaves

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    We examined the changes of chemical composition and protein conformation in Arabidopsis leaves by Fourier transform-infrared (FT-IR) spectrometry Arabidopsis under 50 mmol/L NaCl salt and -0.5 mPa polyethylene glycols 8000 (PEG 8000) drought stress during the early stages of growth.We primarily analyzed the absorption band areas in the 1,745 cm-1 (ester),1,600-1,700 cm-1 (amide I),and 1,100 cm-1 (carbohydrate) changes under salt stress and drought stress within 24 hours.The results showed that ester content declined at the beginning and then increased steadily during 24 hours of drought stress.But under salt stress,it de-clined steadily,and it was about 40 percent of the control after 24 hours.The protein synthesis increased by 25 percent after one hour of salt stress and then reached about 85 percent of the control after 24 hours.Under drought stress,the protein synthesis de-creased and reached aminimal level at the 4-hr time point;it then recovered to the control level at the 24-hr point.The patterns of the accumulation of carbohydrates in the 1,100 cm-1 band areas resembled that of amide I band changes under drought stress and salt stress.Analyzing the ratio A1,627cm-1/A1,658cm-1 under drought stress revealed that the leaves’ entire protein structure maintained a higher-level ordered form than did those under salt stress.Thus our results indicate the existence of different strategies of the Arabidopsis adaptation to salt stress and drought stress.

  18. The use of low temperature calories released by nuclear power plants. Effects of soil temperature on the chemical composition of percolate waters

    International Nuclear Information System (INIS)

    Within the frame of studies on pollution from nuclear power plants, investigations were initiated on the use of calories in agriculture and pisciculture. A short-term experiment showed that increase of soil temperature, either by heating or irrigation, acted on the chemical composition of the percolates

  19. What about risk associated with chemical releases of nuclear installations?

    International Nuclear Information System (INIS)

    The French authority for nuclear safety requests the French institute of radiation protection (IRSN) to perform impacts assessment for the chemical discharges from nuclear facilities in the context of licensing operator. To carry out its mission, IRSN developed assessment methods and a computer tool named CALIES (CALcul d'Impact Environnemental et Sanitaire des rejets d'effluents chimiques liquides et gazeux - Risk assessment for environment and population). (author)

  20. Estimation of optical chemical shift in nuclear spin optical rotation

    International Nuclear Information System (INIS)

    Highlights: • Analytical theory of nuclear spin optical rotation (NSOR) is further developed. • Derive formula of NSOR ratio R between different nuclei in a same molecule. • Calculated results of R agree with the experiments. • Analyze influence factors on R and chemical distinction by NSOR. - Abstract: A recently proposed optical chemical shift in nuclear spin optical rotation (NSOR) is studied by theoretical comparison of NSOR magnitude between chemically non-equivalent or different element nuclei in the same molecule. Theoretical expressions of the ratio R between their NSOR magnitudes are derived by using a known semi-empirical formula of NSOR. Taking methanol, tri-ethyl-phosphite and 2-methyl-benzothiazole as examples, the ratios R are calculated and the results approximately agree with the experiments. Based on those, the important influence factors on R and chemical distinction by NSOR are discussed

  1. Chemical transformations during heating of carborane-containing resols and resites

    International Nuclear Information System (INIS)

    Chemical transformations were studied during the heating of resols containing carborane and corresponding resites. It was found that in the temperature range 50-2000, structure formation of oligomers containing carborane takes place by a mechanism which is conventional for resols. At temperatures higher than 2000 significant chemical transformations of carborane groups of resites take place, the degree of transformations depending on conditions of heating (air, vacuum). It was shown that the most considerable differences in thermal stability of conventional phenol-formalhyde and carborane-containing resites are observed under conditions of thermal oxidizing breakdown. Thermal oxidizing breakdown of several model compounds was studied

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

    International Nuclear Information System (INIS)

    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

  3. About the safety of power transformers in nuclear power plants

    International Nuclear Information System (INIS)

    Oil-filled transformer explosions are due to electrical arcs occurring in transformer tanks. Within milliseconds, arcs vaporize the surrounding oil and the generated gas is quickly pressurized. The pressure difference between the gas bubble and the surrounding liquid oil generates one dynamic pressure peak which propagates and interacts with the tank. Then, the reflections of the pressure peak build up the static pressure, which rises and leads to the tank rupture since tanks are not designed to withstand such levels of static pressure. This results in dangerous explosions, expensive damages and possible environmental pollution. While protective walls surrounding transformers can contain the explosion and sprinklers can fight the induced fire, the current paper presents a strategy to prevent the transformer tank rupture. Once an electrical fault occurs, the fast depressurization of the tank is induced by quick oil evacuation to a reservoir in order to prevent the tank explosion. To evaluate the efficiency of this strategy, experiments and computer simulations are used. The experiments were performed on large scale transformers equipped with the protection. Besides, simulations of the consequences of an electrical arc occurring in a 200 MVA transformer geometry were run and the pressure maps obtained with and without protection were compared. (authors)

  4. Evaluation of thorium based nuclear fuel. Chemical aspects

    International Nuclear Information System (INIS)

    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.)

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

    International Nuclear Information System (INIS)

    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)

  6. 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.

  7. Reactions of charged and neutral recoil particles following nuclear transformations

    International Nuclear Information System (INIS)

    The status of the following programs is reported: study of the stereochemistry of halogen atom or ion reactions produced via (eta,γ) or (IT) nuclear reactions with diastereomeric molecules; study of nuclear decay induced reactions of halogen species with organic compounds in the gas phase; decay-induced labelling of compounds of biochemical interest; energetics and mechanisms involved in the reactions of highly energetic carbon-11 atoms with simple organic molecules; and chemistry of the positronium. (LK)

  8. Solution-phase synthesis of inorganic nanostructures by chemical transformation from reactive templates

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The solution-phase synthesis by chemical transformation from reactive templates has proved to be very effective in morphology-controlled synthesis of inorganic nanostructures. This review paper summarizes the recent progress in solution-phase synthesis of one-dimensional and hollow inorganic nanostructures via reactive templates, focusing on the approaches developed in our lab. The formation mechanisms based on reactive templates are discussed in depth to show the general concepts for the preparation processes. An outlook on the future development in this area is also presented.

  9. Chemical aspects of nuclear methods of analysis

    International Nuclear Information System (INIS)

    This final report includes papers which fall into three general areas: development of practical pre-analysis separation techniques, uranium/thorium separation from other elements for analytical and processing operations, and theory and mechanism of separation techniques. A separate abstract was prepared for each of the 9 papers

  10. The effects of nuclear detonations and nuclear war

    International Nuclear Information System (INIS)

    Nuclear war conjures up images of mass destruction and mutilation that few are willing to contemplate in detail. This paper reviews the effects of nuclear explosions and describes the damage that might result from various types of nuclear strikes

  11. Chemical latent heat for transport of nuclear energy over long distances

    International Nuclear Information System (INIS)

    The oil crisis has made clear the necessity to use nuclear energy to an increasing extent for purposes of energy supply and, particularly, for the supply of non-electric energy market. This purpose is served by the energy supply system 'Nuclear Energy over Long Distances', by which nuclear energy is transported in a converted form and transformed into the applicable forms of energy such as hot water or water vapour and electricity. The energy transport involves the transport of the 'latent heat gas', which by chemical reactions will be absorbing or emitting thermal energy. The latent heat gas 'sythesis gas/methane' presents several substantial advantages. The nuclear heat source of the energy supply system 'Nuclear Energy over Long Distances' is the high-temperature reactor. (author)

  12. Effects of atomic electrons on nuclear stability and radioactive decay

    International Nuclear Information System (INIS)

    . The major conclusion of the paper is that the potentiality of a hypothetical collective process of low-energy nuclear transformations is shown to be compatible with the known fundamental conservation laws. This claim is suggested by our successful attempt for a phenomenological description of such a process - first of all, by a number of successful qualitative predictions verified by the experiment. Specifically, comparison of the results of our modeling with respective experimental data shows that the known fundamental conservation laws allow the existence of a hypothetical collective process of low-energy nuclear transformations, which may manifest itself in the following way. This process may proceed at small input/output energies per participating atom, namely those of the scale of chemical energies. The final ensembles of chemical elements with values of energy closest to that of the initial ensemble appear to consist of stable isotopes, if the initial ensemble consists of stable isotopes as well. In other words, the success of the proposed phenomenological model may be considered as an indirect evidence for probable collective nature of a hypothetical process of nuclear transformation and, probable importance of weak interactions in describing the above process (more precisely - the importance of proton-neutron transformations due to the known fundamental interactions, namely, weak interaction, or some unknown ones). Elaboration of the proposed model, even without specification of the mechanism of transformation, will allow making preliminary estimates of the expected production of elements from the given input elements, and what is even more important, estimating the relevant input elements to produce requested output elements. (authors)

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

    International Nuclear Information System (INIS)

    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)

  14. 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.

  15. Application of nuclear chemical technology to minor metal recovery

    International Nuclear Information System (INIS)

    Toshiba has been developing reprocessing technology in order to establish a nuclear fuel cycle for the transition period from Light Water Reactors (LWRs) to Fast Reactors (FRs). We have developed a new technology called Toshiba Hybrid Reprocessing Process. The process contains the solvent extraction and molten salt electrolysis to obtain high-purity uranium for LWR fuel and low-purity plutonium with minor actinides for FR fuel. The availability of the process to actual spent fuels was experimentally confirmed. Moreover we attempted applications of the nuclear chemical technology to general purposes such as a recovery of minor metals from industrial motors. In this article, some examples of the application are introduced. (author)

  16. Plant metabolites of the Siberian flora. Chemical transformations and the scope of practical application

    Science.gov (United States)

    Shults, Elvira E.; Raldugin, Victor A.; Volcho, Konstantin P.; Salakhutdinov, Nariman F.; Tolstikov, Genrikh A.

    2007-07-01

    The results of studies of some terpenoids, alkaloids and phenolic derivatives isolated from Siberian plants are summarised. The structures of the compounds studied are presented and the chemical transformations of the available terpenoids and alkaloids are considered. Examples of practical application of natural compounds and their derivatives are given.

  17. Transformation by viral and cellular oncogenes of a mouse BALB/3T3 cell mutant resistant to transformation by chemical carcinogens.

    OpenAIRE

    Ono, M; Yakushinji, M; Segawa, K.; Kuwano, M

    1988-01-01

    The mouse cell line MO-5 is resistant to transformation by various chemical carcinogens and also by UV irradiation (C. Yasutake, Y. Kuratomi, M. Ono, S. Masumi, and M. Kuwano, Cancer Res. 47:4894-4899, 1987). Northern (RNA) blot analysis showed active expression of ras and myc genes in MO-5 and BALB/3T3 cells. The effect of transfection of various oncogenes on transformation was compared in MO-5 cells and parental BALB/3T3 cells. Activated c-H-ras, c-N-ras, and v-mos gene induced transformati...

  18. Effect of Corrosive Sulphur to Properties of Transformer Oils

    Czech Academy of Sciences Publication Activity Database

    Papežová, Barbora; Matějková, Martina; Maléterová, Ywetta; Kaštánek, František; Šolcová, Olga

    Bratislava: Slovak Society of Chemical Engineering, 2015 - (Markoš, J.), s. 152 ISBN 978-80-89475-14-8. [International Conference of Slovak Society of Chemical Engineering /42./. Tatranské Matliare (SK), 25.05.2015-29.05.2015] R&D Projects: GA TA ČR(CZ) TA04020151 Institutional support: RVO:67985858 Keywords : corrosive sulphur * transformer iols * sorption Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  19. 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.

  20. The Effect of Quantization Error on Display Color Gamut Transformation

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Researchers and designers who work with color displays often transform color gamut between two different display devices. This paper demonstrates the effect of quantization error on the transformation based on analyzing the color gamut deviation profoundly.

  1. Effect of Exposure to Electrical Discharge on Transformer Oil Properties

    Institute of Scientific and Technical Information of China (English)

    J. S. N'Cho; I. Fofana; T. Aka-Ngnui; A. Beroual

    2011-01-01

    Petroleum based oils, the so-called mineral oils, are used for impregnating solid insulations or filling products of very large number of electric materials: transformers, reactors, cables, bushings, circuit breakers, tap changers, etc. In these equipments, oil is exposed to electrical stress and may experience electrical discharges under certain circumstances. Since the electrical stress is unavoidable in power equipments, the ability of oil to resist decomposition under electrical stress is of great importance for the safety of these devices. Electrical stress together with heat and moisture, in the presence of oxygen, oxidises the oil producing free radicals, acids and sludge that are deleterious to the transformer. In this paper, the effect of electrical discharges on oil properties is reported. The results indicate that quality of oil is considerably affected with increasing voltage stress. Comparing oil properties before and after voltage application allows assessing the outcome of random secondary chemical reactions between large oil born free radicals.

  2. 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…

  3. Simple chemical transformation of lignocellulosic biomass into furans for fuels and chemicals.

    Science.gov (United States)

    Binder, Joseph B; Raines, Ronald T

    2009-02-11

    Lignocellulosic biomass is a plentiful and renewable resource for fuels and chemicals. Despite this potential, nearly all renewable fuels and chemicals are now produced from edible resources, such as starch, sugars, and oils; the challenges imposed by notoriously recalcitrant and heterogeneous lignocellulosic feedstocks have made their production from nonfood biomass inefficient and uneconomical. Here, we report that N,N-dimethylacetamide (DMA) containing lithium chloride (LiCl) is a privileged solvent that enables the synthesis of the renewable platform chemical 5-hydroxymethylfurfural (HMF) in a single step and unprecedented yield from untreated lignocellulosic biomass, as well as from purified cellulose, glucose, and fructose. The conversion of cellulose into HMF is unabated by the presence of other biomass components, such as lignin and protein. Mechanistic analyses reveal that loosely ion-paired halide ions in DMA-LiCl are critical for the remarkable rapidity (1-5 h) and yield (up to 92%) of this low-temperature (energy and chemical industries. PMID:19159236

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

    International Nuclear Information System (INIS)

    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.

  5. 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. PMID:25443804

  6. Nuclear Weapons Enterprise Transformation - A Sustainable Approach

    International Nuclear Information System (INIS)

    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

  7. Nuclear and conventional energy transformation

    International Nuclear Information System (INIS)

    Atmospheric pollution from fossil fuel- and nuclear power plants have been compared. SO2 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.)

  8. Testing of advance design types of instrument current transformers for Temelin nuclear power plant

    International Nuclear Information System (INIS)

    Current transformers designed and produced in IVEP Brno for the measurement of electric energy, for control and protection of the generator-transformer unit of the Temelin nuclear power plant are described. Presented are tests performed according to the standard test CSN 35 1360 and CSN 35 1361 as well as tests respecting a revision of these standards according to IEC 185. (author) 1 tab., 2 figs., 7 refs

  9. The Violation of Childhood: A Review of Possible Effects on Development of Toxic Chemical and Nuclear Waste.

    Science.gov (United States)

    Evans, Roy

    Emphasizing that for any known teratogen no safe dosage level exists, this case-illustrated review identifies the bases for current concern about the pollution of the environment, reflects on the promise and complexities of the emerging disciplines of behavioral toxicology and behavioral teratology, and describes existing evidence of teratogenic…

  10. Modification of valencene by bio- and chemical transformation.

    Science.gov (United States)

    Asakawa, Yoshinori; Hashimoto, Toshihiro; Noma, Yoshiaki; Furusawa, Mai

    2013-07-01

    Highly efficient production is discussed of nootkatone, the most important fragrant component of grapefruit and which possesses anti-obesity activity, from valencene, obtained from Valencia orange, by the green alga, Chlorella, and the fungi, Mucor, Botryospaeria and Botryodiplodia. The microorganisms introduce an oxygen atom at an allylic position to give secondary hydroxyl and keto groups. The presented methods are a cheap one step reaction, non-hazardous and very useful for the production of fragrant components from commercially available natural sesquiterpene hydrocarbons. PMID:23980411

  11. Sorption and chemical transformation of PAHs on coal fly ash. Technical progress report No. 1, [October--December 1991

    Energy Technology Data Exchange (ETDEWEB)

    Mamantov, G.; Wehry, E.L.

    1991-12-31

    The objective of this research is to characterize the interactions of coal fly ash with polycyclic aromatic hydrocarbons (PAHs) and their derivatives, and to understand the influence of the surface properties of coal ash (and other atmospheric particles) on the chemical transformations of polycyclic aromatic compounds. Studies to be carried out in this project include: (1) Fractionation of heterogeneous coal fly ash samples into different particle types varying in size and chemical composition (carbonaceous, mineral-magnetic, and mineral nonmagnetic); (2) Measurement of the rates of chemical transformation of PAHs and PAH derivatives (especially nitro-PAHs) and the manner in which the rates of such processes are influenced by the chemical and physical properties of coal fly ash particles; (3) Chromatographic and spectroscopic studies of the nature of the interactions of coal fly ash particles with PAHs and PAH derivatives; (4) Characterization of the fractal nature of fly ash particles (via surface area measurements) and the relationships of ``surface roughness`` of fly ash particles to the chemical behavior of PAHs sorbed on coal ash particles; (5) Identification of the major products of chemical transformation of PAHs on coal ash particles, and examination of any effects that may exist of the nature of the coal ash surface on the identities of PAH transformation products; and (6) Studies of the influence of other sorbed species on the chemical behavior of PAHs and PAH derivatives on fly ash surfaces. PAHs are deposited, under controlled laboratory conditions, onto coal ash surfaces from the vapor phase, in order to mimic the processes by which PAHs are deposited onto particulate matter in the atmosphere.

  12. Chemical Genomics Profiling of Environmental Chemical Modulation of Human Nuclear Receptors

    OpenAIRE

    Huang, Ruili; Xia, Menghang; Cho, Ming-Hsuang; Sakamuru, Srilatha; Shinn, Paul; Houck, Keith A.; Dix, David J; Judson, Richard S.; Witt, Kristine L.; Kavlock, Robert J.; Tice, Raymond R.; Austin, Christopher P.

    2011-01-01

    Background: The large and increasing number of chemicals released into the environment demands more efficient and cost-effective approaches for assessing environmental chemical toxicity. The U.S. Tox21 program has responded to this challenge by proposing alternative strategies for toxicity testing, among which the quantitative high-throughput screening (qHTS) paradigm has been adopted as the primary tool for generating data from screening large chemical libraries using a wide spectrum of assa...

  13. Effect of α-tocopherol and its sulfur-containing analogs on radiation-induced chemical transformations of hexane and ethanol

    International Nuclear Information System (INIS)

    A series of sulfur-containing structural analogs of α-tocopherol was synthesized, and their effect on the formation of molecular products of ethanol and hexane radiolysis under aerated and deaerated conditions was studied. The O-H bond dissociation enthalpies (BDEs) were calculated for the compounds containing hydroxyl groups. It was found that α-tocopherol and its analogs have the most significant effect on the radiolysis of ethanol and hexane under air-free conditions when the products are formed in the reactions of carbon centered radicals. The probability of the reaction of the test compounds with alkyl radicals increases with a decrease in the BDE for the OH groups present in these compounds. The carbonyl group in compounds makes them efficient oxidants of α-hydroxyalkyl radicals, thus resulting in a change in the product composition for the ethanol radiolysis in the presence of these compounds

  14. Atmospheric effects of nuclear war

    International Nuclear Information System (INIS)

    A review of recent computer model studies of the global atmospheric consequences of nuclear war is presented. The studies predict that sub-freezing surface temperatures and semi-darkness beneath regional-scale smoke and dust clouds are the most serious long-term atmospheric repercussions following a nuclear exchange. These studies and the subsequent predictions of global ecological disaster by some biologists have aroused considerable contention amongst scientists from many disciplines. Despite this contention, the predictions of the models reviewed here remain unrefuted. However, from the models so far published the severity of the predicted atmospheric effects and their temporal evolution, particularly in the Southern Hemisphere, cannot be accurately forecast

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

    International Nuclear Information System (INIS)

    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)

  16. Physico-chemical transformations of sulfated compounds during the leaching of highly sulfated cemented wastes

    International Nuclear Information System (INIS)

    Cementation of sulfated evaporator concentrates leads to highly sulfated low level wastes, (ca. 25% w/w sodium sulfate solution as mix water), which exhibit the presence of U-phase, a sodium-bearing calcium monosulfphoaluminate-like phase. During the leaching of simulated highly sulfated OPC/BFS cements, cured at room temperature and containing U-phase, sodium sulfate, and ettringite, physico-chemical transformations have been pointed out (transformation of U-phase into ettringite). Samples having the same chemical composition, but cured at high temperature (maximal temperature during curing: 120 C), do not contain ettringite initially, but secondary ettringite is formed during leaching. XRD spectra point out the existence of precipitation fronts (or of phase formation fronts) varying linearly versus the square root of time. The analysis of leaching solutions has provided complementary data used in a code, the aim of which is to assess cement degradation, based on coupling between transport by diffusion and chemical reactions (DIFFUZON code). The U-phase-ettringite transformation is confirmed

  17. Climatic effects of nuclear war

    International Nuclear Information System (INIS)

    Global climatic consequences of a nuclear war have, until recently, been assumed to be insignificant compared with the obviously devastating direct effects from blast, heat, and short-term fallout. But a number of investigations carried out over the past few years indicate that climatic impact could actually be severe enough to threaten the global ecosystem significantly, including regions that may not have been directly involved in the war. This change in perception comes as researchers realize that the fires ignited by nuclear explosions would generate so much smoke that, even spread over a large portion of Earth's surface, densities could be high enough to block most of the sunlight normally reaching the ground. As a result, temperatures could decrease below freezing in a nuclear winter lasting weeks to months. Smoke from fires is what would make nuclear winter so severe. Of necessity, theoretical models are relied upon to estimate the climatic impact of nuclear war. The models incorporate many uncertain assumptions, particularly regarding the small-scale details of smoke production by fires

  18. 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)

  19. Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium metal

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2004-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium metal to determine compliance with specifications.

  20. 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....

  1. Nuclear quantum effects in chemical reactions via higher-order path-integral calculations

    International Nuclear Information System (INIS)

    Highlights: • The study presents path-integral calculations for chemical reactions. • The path-integrals use higher-order factorizations of the density matrix. • The Eckart potential and the H2 + H reaction are used as test cases for the methods. • The Chin higher order factorization enhances QM transmission convergence. • The higher order factorizations enhance eigenvalue and partition function convergence. - Abstract: A practical approach to treat nuclear quantum mechanical effects in simulations of condensed phases, such as enzymes, is via Feynman path integral (PI) formulations. Typically, the standard primitive approximation (PA) is employed in enzymatic PI simulations. Nonetheless, these PI simulations are computationally demanding due to the large number of beads required to obtain converged results. The efficiency of PI simulations may be greatly improved if higher-order factorizations of the density matrix operator are employed. Herein, we compare the results of model calculations obtained employing the standard PA, the improved operator of Takahashi and Imada (TI), and a gradient-based forward corrector algorithm due to Chin (CH). The quantum transmission coefficient is computed for the Eckart potential while the partition functions and rate constant are computed for the H2 + H hydrogen transfer reaction. These potentials are simple models for chemical reactions. The study of the different factorization methods reveals that in most cases the higher-order action converges faster than the PA and TI approaches, at a moderate computational cost

  2. 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.)

  3. Application of wavelet transforms as a time-series analysis tool for nuclear thermalhydraulics

    International Nuclear Information System (INIS)

    Wavelet transforms can be a valuable time-series analysis tool in the field of nuclear thermalhydraulics. As an example, the Morlet wavelet transform can be used to reduce the aleatory (random) uncertainty of a voiding transient in a large loss of coolant accident (LOCA). The wavelet transform is used to determine the cutoff frequency for a low pass Butterworth filter in order to remove the noisy part of the signal without infringing upon the characteristic frequencies of the phenomenon. This technique successfully reduced the standard random uncertainty by 42.4%. (author)

  4. Materials ``alchemy'': Shape-preserving chemical transformation of micro-to-macroscopic 3-D structures

    Science.gov (United States)

    Sandhage, Kenneth H.

    2010-06-01

    The scalable fabrication of nano-structured materials with complex morphologies and tailorable chemistries remains a significant challenge. One strategy for such synthesis consists of the generation of a solid structure with a desired morphology (a “preform”), followed by reactive conversion of the preform into a new chemistry. Several gas/solid and liquid/solid reaction processes that are capable of such chemical conversion into new micro-to-nano-structured materials, while preserving the macroscopic-to-microscopic preform morphologies, are described in this overview. Such shape-preserving chemical transformation of one material into another could be considered a modern type of materials “alchemy.”

  5. Immunobiological properties of sesquiterpene lactones obtained by chemically transformed structural modifications of trilobolide.

    Science.gov (United States)

    Harmatha, Juraj; Vokáč, Karel; Buděšínský, Miloš; Zídek, Zdeněk; Kmoníčková, Eva

    2015-12-01

    Our previous research on immunostimulatory properties of trilobolide and its structurally related natural analogues isolated from Laser trilobum (L.) Borkh., encouraged us to investigate structurally related guaianolides belonging to a specific group of sesquiterpene lactones with characteristic glycol moiety attached to the lactone ring. Ever increasing attention has been paid to certain guaianolides such as thapsigargin and trilobolide for their promising anti-inflammatory, anticancer, anti-infectious and SERCA inhibitory activities. However, due to their alkylation capabilities, they might be cytotoxic. Search for compounds with preserved immunobiological properties and decreased cytotoxicity led us to transform some of their structural features, particularly those related to their side chain functionality. For this reason, we prepared a series of over 20 various deacylated, acyl modified, or relactonized derivatives of trilobolide. The immunobiological effects were screened in vitro using the rat peritoneal cells primed with lipopolysaccharide. Secretion of interferon-γ (IFN-γ), interleukins (IL) IL-1β, IL-6 and tumour necrosis factor-α (TNF-α) were determined by ELISA, and nitric oxide (NO) production by Griess reagent. Relation between the molecular structure and immunobiological activity was investigated. Acetylation at 7-OH and 11-OH positions of the lactone ring, or acyl modification of the guaianolide functionalities (including relactonization) of trilobolide, led to inability to stimulate secretion of cytokines and production of NO. Interestingly, minor structural changes achieved by catalytic hydrogenation or hydrogenolysis retained the original immunoactivity of trilobolide. It can be concluded that several new chemically transformed sesquiterpene lactones resembling the immunobiological properties of trilobolide or thapsigargin were prepared and identified. The implication of the lactone vicinal diol (glycol) moiety, combined with other structure

  6. Efficient and selective chemical transformations under flow conditions: The combination of supported catalysts and supercritical fluids

    OpenAIRE

    M. Isabel Burguete; Eduardo García-Verdugo; Luis, Santiago V.

    2011-01-01

    This paper reviews the current trends in the combined use of supported catalytic systems, either on solid supports or in liquid phases and supercritical fluids (scFs), to develop selective and enantioselective chemical transformations under continuous and semi-continuous flow conditions. The results presented have been selected to highlight how the combined use of those two elements can contribute to: (i) Significant improvements in productivity as a result of the enhanced diffusion of substr...

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

    International Nuclear Information System (INIS)

    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

  8. The role of non-ras transforming genes in chemical carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, C.S. (Inst. of Cancer Research, Surrey (England))

    1991-06-01

    DNA transfection experiments using the NIH 3T3 mouse fibroblast cell line have demonstrated that chemically induced tumors and chemically transformed cell lines frequently contain dominant transforming genes. Although many of the genes detected using the NIH 3T3 transfection-transformation assay are activated versions of H-ras, K-ras, and N-ras, in some experimental systems activated forms of genes such as met and neu that are unrelated to ras have been observed. The activated met gene was originally detected in a human cell line that had been transformed by exposure to N-methyl-N{prime}-nitro-N-nitrosoguanidine. Subsequent studies demonstrated that the met proto-oncogene encodes a novel growth factor receptor and that gene activation involves the production of a chimeric gene in which the regions of met encoding the extracellular and transmembrane domains of the receptor are replaced by the 5{prime}-region of an unrelated gene called trp. The presence of genetic alterations in chemically induced malignancies has also been assessed in cytogenetic studies and by Southern analysis of DNA from neoplastic cells. These studies have demonstrated the presence of altered versions the c-myc and mos genes in plasmocytomas induced in mice following exposure to pristane or mineral oil and of activated pim-1 and c-myc genes in thymomas that arise in AKR mice following treatment with N-methyl-N-nitrosourea. Analyses of the mechanisms of activation of these non-ras genes has provided important insights into the different ways in which genes may become activated following chemical exposure.

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

    International Nuclear Information System (INIS)

    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)

  10. Climatic effects of nuclear war

    International Nuclear Information System (INIS)

    Recent findings by this group confirmed by workers in Europe, the US and the USSR, suggest that the long-term climatic effects of a major nuclear war are likely to be much severer and farther-reaching than had been supposed. In the aftermath of such a war vast areas of the earth could be subjected to prolonged darkness, abnormally low temperatures, violent windstorms, toxic smog and persistent radioactive fallout - in short, the combination of conditions that has come to be known as nuclear winter. In brief, the authors' initial results, published in Science in December, 1983, showed that the potential global atmospheric and climatic consequences of nuclear war...are serious. Significant hemispherical attenuation of the solar radiation flux and subfreezing land temperatures may be caused by fine dust raised in high-yield nuclear surface bursts and by smoke from city and forest fires ignited by airbursts of all yields. Subsequent studies, based on more powerful models of the general circulation of the earth's atmosphere, have tended to confirm both the validity of the authors' investgative approach and the main thrust of their findings. Most of this article is devoted to reviewing the current state of knowledge on this vital issue

  11. Synthesis and the Structural Transformation of fcc to hcp in Ni-Graphene Nanocomposite by Simple Chemical Route via Sonication

    OpenAIRE

    N. K. Mahale; R. D. Ladhe; Attarde, S. B.; S. T. Ingle

    2014-01-01

    We report the synthesis and structural transformation of fcc to hcp in Ni-graphene (Ni-Gr) composite by simple chemical route via sonication. The syntheses of Ni-Gr composite by simultaneous reduction method, and the effect of different composition ratio on morphology and crystal structure were examined in our present study. The results indicated that the graphene ratio played an important role in crystal structure and d-spacing in nickel crystals. Different compositions have shown different ...

  12. Isotope effects of sulfur in chemical reactions

    International Nuclear Information System (INIS)

    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)

  13. Overview of climatic effects of nuclear winter

    International Nuclear Information System (INIS)

    A general description of the climatic effects of a nuclear war are presented. This paper offers a short history of the subject, a discussion of relevant parameters and physical processes, and a description of plausible nuclear winter scenario. 9 refs

  14. The Effects of Nuclear Weapons

    Energy Technology Data Exchange (ETDEWEB)

    Glasstone, Samuel

    1957-06-01

    This handbook prepared by the Armed Forces Special Weapons Project of the Department of Defense in coordination with other cognizant government agencies and published by the United States Atomic Energy Commission, is a comprehensive summary of current knowledge on the effects of nuclear weapons. The effects information contained herein is calculated for yields up to 20 megatons and the scaling laws for hypothetically extending the calculations beyond this limit are given. The figure of 20 megatons however is not be taken as an indication of capabilities or developments.

  15. Radiation-chemical transformation of synthetic oil from oil-bituminous rock

    International Nuclear Information System (INIS)

    Full text : Like as test subject was used synthetic oil from oil-bituminous rocks of Balakhany deposit. The regularities of synthetic oils radiation-chemical transformations were studied. Laboratory researches were carried out in an interval of absorbed dose 43-216 kGr and dose rate 0.5 Gr/s. Concentration, radiation-chemical yields of the received gases in the various absorbed doses were established. Results of researches allow to estimate possibility use of oil products received from synthetic oil for isolation of radioactive sources from environment. The purpose of the given work is research of radiation stability of synthetic oil from bituminous rock. Results of such researches will allow to estimate possibility of production different purpose oil products from synthetic oil in a radiation-chemical way and also use of these materials for isolation of radioactive sources from environment

  16. Atmospheric effects of nuclear war

    International Nuclear Information System (INIS)

    The above uncertainties in the nuclear winter calculations are not one-sided. It is possible that certain errors would cause over estimation of the effects, while others could just as easily cause underestimation. Although the calculations involve material and processes that are complex, and for which the present state of knowledge is limited, the rather simple 1-dimensional models were quite correct in establishing the possibility of large-scale climatic perturbations following a nuclear war. The main conclusions regarding the possible climate effects of the nuclear war are: for large smoke injections, occurring between April and September in the northern hemisphere, land surface temperatures could decrease by 10-25 degrees C below normal in continental areas within a few days; the initial smoke distribution would be patchy, so temperature fluctuations could be spatially and temporally quite variable; within a few weeks, the smoke would be spread throughout much of the northern hemisphere. For spring-summer injections, a substantial fraction of the smoke would be transported, by solar heating, up into the stratosphere; surface temperatures of much of the northern hemisphere could drop to wintertime levels. Precipitation would also be affected; and stratospheric smoke could also be transported toward the equator, resulting in atmospheric perturbations in the southern hemisphere. Although recent developments have indicated that surface temperature reductions may be 25% less than suggested earlier, there is substantial reason to believe that severe climatic perturbations are the probable outcome of nuclear war and that these disturbances could cause more human casualties globally than the direct effects

  17. Bioprocessing applications in the management of nuclear and chemical wastes

    International Nuclear Information System (INIS)

    The projected requirements for waste management and environmental restoration activities within the United States will probably cost tens of billions of dollars annually during the next two decades. Expenditures of this magnitude clearly have the potential to affect the international competitiveness of many US industries and the continued operation of many federal facilities. It is argued that the costs of implementing current technology will be too high unless the standards and schedules for compliance are relaxed. Since this is socially unacceptable, efforts to improve the efficiency of existing technologies and to develop new technologies should be pursued. A sizable research, development, and demonstration effort can be easily justified if the potential for reducing costs can be shown. Bioprocessing systems for the treatment of nuclear and chemically hazardous wastes offer such promise. 11 refs

  18. 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.

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

    International Nuclear Information System (INIS)

    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 13C 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 13C NMR, 2D-HSQC, and 31P-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

  20. Bioprocessing applications in the management of nuclear and chemical wastes

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE), the US Department of Defense (DOD), and other federal agencies already face profound challenges in finding strategies that manage budgets and priorities while bringing their sites and facilities into compliance with current statues and regulations and with agency policies and orders. While it is often agreed that current technology can be used to address most waste management and environmental restoration needs, it is also argued by many that the costs of implementing current technology will be too high unless the standards and schedules for compliance are relaxed. Since this is socially unacceptable, efforts to improve the efficiency of existing technologies and to develop new technologies should be pursued. A sizable research, development, and demonstration effort can be easily justified if the potential for reducing costs can be shown. Bioprocessing systems for the treatment of nuclear and chemically hazardous wastes offer such promise

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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.)

  3. 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. PMID:16920155

  4. Long-range transport of Saharan dust and chemical transformations over the Eastern Mediterranean

    Science.gov (United States)

    Athanasopoulou, E.; Protonotariou, A.; Papangelis, G.; Tombrou, M.; Mihalopoulos, N.; Gerasopoulos, E.

    2016-09-01

    Three recent Saharan dust outbreaks during different seasons (4-6 days in winter of 2009, late autumn of 2010 and summer of 2011) are selected in order to study the chemical footprint and aging processes of dust intrusions over the Eastern Mediterranean (EM). The applied model system (PMCAMx, WRF and GEOS-CHEM) and methodology are found competent to reproduce dust production, long-range transport and chemical transformations over the EM, with the synergistic use of synoptic patterns analysis, optical depth retrievals, back-trajectories, surface and satellite aerosol measurements. The dust loads were high during the cold period events and much lighter during summertime, when transport was mainly in the free troposphere. In all cases, dust originated from the northwest and/or west Saharan desert and reached the EM from the west/southwest. Sensitivity runs underlie the effect of dust transport on the chemical constituents of aerosols over the EM and show a large impact on calcium (70-90% of maximum daily values 2-5 μg m-3), with its gradient at surface level being around -10% per 100 km along the dust pathway. For the cold period cases, this value can also be considered analogous to the dust dissipation ratio, because the plume is vertically extended down to the surface layers. Interestingly, the surface particulate nitrate concentrations over the EM are reversely affected by the approaching dust loads, exhibiting the highest values (up to 6 μg m-3) and the largest dust fraction (ca. 70%) during summertime. This is attributed to the enhanced nitric acid formation under high atmospheric temperature and insolation, its uptake onto the carbonate dust particles, and their effective accumulation, due to low deposition rates over the sea and scarce precipitation. Sulfate formation onto dust particles is found insignificant (rapid reaction with ammonia and/or sea-salt), while the influence of dust and sea-salt on sodium, when spatio-temporal averages are calculated, is

  5. The effects of nuclear weapons

    International Nuclear Information System (INIS)

    At least 40% of the population of Hiroshima and 26% of that of Nagasaki were killed in the nuclear attacks. The early and late effects in these two cities and in relation to present weaponry are briefly discussed. The effects of blast, heat and initial and delayed radiation are outlined. Neutron and gamma doses as functions of slant distances for bombs of various specified yields are presented. Dose rates for fallout at various times after explosions in terms of wind velocity and various cloud formations are also outlined. In Western Europe there are only 145 cities with populations of over 200,000. It is concluded that the destruction of these cities would kill in a short time more than one third of the population of Western Europe, and in a nuclear world war, not only would a fair part of the urban population in the Northern Hemisphere be killed by fire and blast, and most of the survivors by radiation, but much of the rural population would be killed by radiation from fallout. Many millions in the Southern Hemisphere would also be killed by fallout radiation. (U.K.)

  6. Exhibition of the periodicity of Quantum Fourier Transformation in Nuclear Magnetic Resonance

    OpenAIRE

    Peng, Xinhua; Zhu, Xiwen; Fang, Ximing; Feng, Mang; Yang, Xiaodong; Liu, Maili; Gao, Kelin

    2002-01-01

    The remarkable capability of quantum Fourier transformation (QFT) to extract the periodicity of a given periodic function has been exhibited by using nuclear magnetic resonance (NMR) techniques. Two separate sets of experiments were performed. In a full QFT, the periodicity were validated with state tomography and fidelity measurements. For a simplified QFT, the three-qubit pseudo-pure state was created by introducting an additional observer spin, and the spectra recorded on the observer spin...

  7. Chemical Transformations Associated with the Reaction (n, γ) on TeVI and with the Isomeric Transitions of Hexavalent Radiotellurium

    International Nuclear Information System (INIS)

    The chemical transformations accompanying neutron irradiation of telluric acid were studied under varying experimental conditions. In particular, a study was made of the consequences of the (n, γ) reaction on TeVI , as well as those of the isomeric transitions Te131m VI γ Te131 and Te129m VI γ Te129. The existence of a Szilard-Chalmers effect was demonstrated. As radiotellurium appears mainly in the hexa- and tetravalent states, we determined the retention of Te*VI by separating Te*IV and Te*VI by chromatography, paper electrophoresis or extraction with solvents. The retention of Te*VI in telluric acid irradiated to a crystallized state has substantially the same value for the basic isomers T131, Te129 and the system Te131 +Te129 + Te127. It depends upon the type of reactor chosen, its mean value varying from about 39% to 55%. It increases slightly with the duration of irradiation and rises if the acid is irradiated in an aqueous solution. The total retention R of the metastable isomers (Te129m, Te127m, Te125m, Te123m, Te121m + Te121) is particularly important because it can reach more than 98%. It seems tc be independent of the solvent in the case of crystallized telluric acid, but grows with the pH if irradiation takes place in solution. R increases still further with the concentration of TeVI and the duration of irradiation; it decreases with the degree of hydration of the acid. The internal conversion of gamma radiation in isomeric transitions brings about a reduction in the fundamental isomer (Te131 or Te129) when its precursor is in a hexavalent state. The corresponding retention depends upon the pH and increases with it. In particular, it increases from 40% to 80% for the isotope Te129 as we go from HCl 3M to NaOH 6M. The retention of Te131VI seemed lower than that of Te129VI but the existence of an isotope effect remains uncertain. In the course of the nuclear transformations studied, the reduction of Te*VI to Te*IV seems to take place through a similar

  8. Chemical transformation of CO2 during its capture by waste biomass derived biochars.

    Science.gov (United States)

    Xu, Xiaoyun; Kan, Yue; Zhao, Ling; Cao, Xinde

    2016-06-01

    Biochar is a porous carbonaceous material with high alkalinity and rich minerals, making it possible for CO2 capture. In this study, biochars derived from pig manure, sewage sludge, and wheat straw were evaluated for their CO2 sorption behavior. All three biochars showed high sorption abilities for CO2, with the maximum capacities reaching 18.2-34.4 mg g(-1) at 25 °C. Elevating sorption temperature and moisture content promoted the transition of CO2 uptake from physical to chemical process. Mineral components such as Mg, Ca, Fe, K, etc. in biochar induced the chemical sorption of CO2 via the mineralogical reactions which occupied 17.7%-50.9% of the total sorption. FeOOH in sewage sludge biochar was transformed by sorbed CO2 into Fe(OH)2CO3, while the sorbed CO2 in pig manure biochar was precipitated as K2Ca(CO3)2 and CaMg(CO3)2, which resulted in a dominant increase of insoluble inorganic carbon in both biochars. For wheat straw biochar, sorbed CO2 induced CaCO3 transformed into soluble Ca(HCO3)2, which led to a dominant increase of soluble inorganic carbons. The results obtained from this study demonstrated that biochar as a unique carbonaceous material could distinctly be a promising sorbent for CO2 capture in which chemical sorption induced by mineralogical reactions played an important role. PMID:26995449

  9. Influence of the chemical composition on transformation behaviour of low carbon microalloyed steels

    International Nuclear Information System (INIS)

    In order to design thermomechanical schedules for processing low carbon microalloyed steels, the various critical transformation temperatures, i.e. the start and finish of the austenite transformation (Ar3, Ar1) and the non-recrystallization temperature (Tnr), must be determined. Continuous cooling torsion and compression testing are useful ways to measure these values. In this study six low carbon microalloyed steels with different additions (Nb, Cu, Si and Mo) were examined using these techniques. Moreover, the equilibrium phase diagrams for each alloy were calculated using FactSage. The comparison of the thermomechanical testing results with the thermodynamic calculations leads to a better understanding of the effect of the different elements on the transformation behaviour of pipeline steels. Regarding transformation temperatures, Cu in residual contents showed a strong effect on decreasing both Ar3 and Ar1, which indicates a hardenability effect of this element. On the other hand, increasing Nb contents increased Tnr by accelerating Nb(C,N) precipitation. However, when Si was added to a Nb-microalloyed steel, the Tnr decreased.

  10. Health and environmental effects of nuclear weapons

    International Nuclear Information System (INIS)

    This report briefly reviews previous WHO work on the health consequences of nuclear war and concentrates on current information about the effects of nuclear weapons on health, and related environmental problems. 15 refs

  11. A comparison of chemical propulsion, nuclear thermal propulsion, and multimegawatt electric propulsion for Mars missions

    Science.gov (United States)

    Frisbee, Robert H.; Blandino, John J.; Leifer, Stephanie D.

    1991-01-01

    Various propulsion systems are considered for a split-mission piloted exploration of Mars in terms of reducing total initial mass in low earth orbit (IMLEO) as well as trip time. Aerobraked nuclear thermal propulsion (NTP), multimegawatt (MMW) nuclear electric propulsion (NEP), and MMW solar electric propulsion (SEP) are discussed and compared to a baseline aerobraked chemical propulsion system. NTP offers low IMLEO, MMW NEP allows both low IMLEO and a short trip time, and both nuclear systems offer better mission characteristics than the chemical system. The MMW SEP is concluded to be less efficient in spite of a lower IMLEO because of the system's higher specific mass and nonconstant power production. It is recommended that MMW NEP and SEP systems be considered for application to Mars cargo missions. The NEP system is concluded to be the most effective propulsion configuration for piloted Mars missions and lunar base missions.

  12. 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

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

    International Nuclear Information System (INIS)

    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

  14. Influence of Chemical Composition on Phase Transformation Temperature and Thermal Expansion Coefficient of Hot Work Die Steel

    Institute of Scientific and Technical Information of China (English)

    XIE Hao-jie; WU Xiao-chun; MIN Yong-an

    2008-01-01

    On the basis of the uniform design method,six kinds of martensitie hot work die steels were designed.The phase transformation temperatures including Ac1,Ac3,and M,were measured by DIL805A quenching dilatometer.The influences of the main elements on phase transformation temperatures were analyzed by quadratic stepwise regression analysis,and three corresponding equations were obtained.These equations,in which the interactions of the elements were considered,showed more effectiveness than the traditional ones.In addition,the thermal expansion coefficients of these steels in annealed state and quenched state were also obtained during the tests.The influences of chemical composition and temperature on the thermal expansion coefficient were analyzed;the equations obtained Were verified by using several kinds of steels.The predicted values were in accordance with the results of the experiments.

  15. Sampling the structure and chemical order in assemblies of ferromagnetic nanoparticles by nuclear magnetic resonance

    Science.gov (United States)

    Liu, Yuefeng; Luo, Jingjie; Shin, Yooleemi; Moldovan, Simona; Ersen, Ovidiu; Hébraud, Anne; Schlatter, Guy; Pham-Huu, Cuong; Meny, Christian

    2016-05-01

    Assemblies of nanoparticles are studied in many research fields from physics to medicine. However, as it is often difficult to produce mono-dispersed particles, investigating the key parameters enhancing their efficiency is blurred by wide size distributions. Indeed, near-field methods analyse a part of the sample that might not be representative of the full size distribution and macroscopic methods give average information including all particle sizes. Here, we introduce temperature differential ferromagnetic nuclear resonance spectra that allow sampling the crystallographic structure, the chemical composition and the chemical order of non-interacting ferromagnetic nanoparticles for specific size ranges within their size distribution. The method is applied to cobalt nanoparticles for catalysis and allows extracting the size effect from the crystallographic structure effect on their catalytic activity. It also allows sampling of the chemical composition and chemical order within the size distribution of alloyed nanoparticles and can thus be useful in many research fields.

  16. 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)

  17. Study of chemistry transformations of in vivo implanted coral by nuclear analysis methods

    International Nuclear Information System (INIS)

    Neutron activation analysis and use of radioactive tracers, completed by X-rays diffraction, allowed us to quantitatively study the transformations in a biomaterial (coral) implanted 'in vivo'. Before its implantation, the biomaterial is sterilized. Sterilization by thermal effect or irradiation does not induce any macroscopic modification of the crystal structure: the biomaterial preserves its biocompatible properties. Coral was implanted in ovine and procine thighbones. Biopsies were extracted after different implantation times (1 to 24 weeks). The analyzed samples for each biopsy are the intermediate part (initially the coral) and the cortical next to the implant. We have measured the concentrations of Ca, P, Sr and Mg by neutron activation, as a function of the time of implantation. The results show that the mineral composition of the intermediate part is greatly modified. The concentrations of Ca, P, Sr and Mg become comparable to those of a mature about 3 to 5 months after implantation, depending upon the experimentation. The X-rays diffraction analysis of the implant reveals a gradual substitution of the coral aragonite crystal structure by an apatitic structure. The radioactive marking of Ca and Sr, initially constituting coral, allowed to measure the transfers of elements in organism and to specify the mechanisms of its transformations. This study exhibits a Ca and Sr contribution from organism for the bone neoformation. After five months, the calcium of the implant is no longer the one from the biomaterial. These results, obtained by sensitive and selective nuclear methods, suggest a biomaterial resorption followed by a formation of apatite. 68 figs., 57 tabs

  18. The effects of nuclear tests

    International Nuclear Information System (INIS)

    The United States, the Sovjet Union, Britain, France and China have so far completed slightly over 2,000 nuclear tests. At first, the tests were mainly conducted in the atmosphere. The number of atmospheric tests done is slightly over 500. Explosions detonated in the atmosphere were dangerous to all those participating the tests -researchers, workers and military personnel - as well as to the inhabitants living near the test sites. The first hydrogen bomb test carried out by the United States on Bikini Atoll in 1954 caused radioactive fallout that contaminated the nearby atolls and made the crew of a Japanese fishing vessel fall ill. Soldiers participating in military drills conducted in connection with the tests were also exposed to the risks of the atmospheric explosions. Only a few atmospheric tests had direct health effects, but it is still being debated whether the resulting radiation doses affected the diseases that have surfaced later. The veil of secrecy kept up by all countries with nuclear weapons has hampered any investigations into the matter for decades. Nevertheless, in the last few years, some victims of the tests have been paid damages. (orig.) (1 fig.)

  19. Efficient and selective chemical transformations under flow conditions: The combination of supported catalysts and supercritical fluids

    Directory of Open Access Journals (Sweden)

    M. Isabel Burguete

    2011-09-01

    Full Text Available This paper reviews the current trends in the combined use of supported catalytic systems, either on solid supports or in liquid phases and supercritical fluids (scFs, to develop selective and enantioselective chemical transformations under continuous and semi-continuous flow conditions. The results presented have been selected to highlight how the combined use of those two elements can contribute to: (i Significant improvements in productivity as a result of the enhanced diffusion of substrates and reagents through the interfaces favored by the scF phase; (ii the long term stability of the catalytic systems, which also contributes to the improvement of the final productivity, as the use of an appropriate immobilization strategy facilitates catalyst isolation and reuse; (iii the development of highly efficient selective or, when applicable, enantioselective chemical transformations. Although the examples reported in the literature and considered in this review are currently confined to a limited number of fields, a significant development in this area can be envisaged for the near future due to the clear advantages of these systems over the conventional ones.

  20. Chemical transformations of complex mixtures relevant to atmospheric processes: Laboratory and ambient studies

    Science.gov (United States)

    Samy, Shahryar (Shar)

    The study of atmospheric chemistry and chemical transformations, which are relevant to conditions in the ambient atmosphere require the investigation of complex mixtures. In the atmosphere, complex mixtures (e.g. diesel emissions) are continually evolving as a result of physical and chemical transformations. This dissertation examines the transformations of modern diesel emissions (DE) in a series of experiments conducted at the European Outdoor Simulation Chamber (EUPHORE) in Valencia, Spain. Experimental design challenges are addressed, and the development of a NOx removal technology (denuder) is described with results from the application of the newly developed NOx denuder in the most recent EUPHORE campaign (2006). In addition, the data from an ambient aerosol study that examines atmospheric transformation products is presented and discussed. Atmospheric transformations of DE and associated secondary organic aerosol (SOA) production, along with chemical characterization of polar organic compounds (POC) in the EUPHORE experiments, provides a valuable insight on the tranformations of modern DE in environmentally relevant atmospheres. The greatest SOA production occurred in DE with toluene addition experiments (>40%), followed by DE with HCHO (for OH radical generation) experiments. A small amount of SOA (3%) was observed for DE in dark with N2O5 (for NO3 radical production) experiments. Distinct POC formation in light versus dark experiments suggests the role of OH initiated reactions in these chamber atmospheres. A trend of increasing concentrations of dicarboxylic acids in light versus dark experiments was observed when evaluated on a compound group basis. The production of diacids (as a compound group) demonstrates a consistent indicator for photochemical transformation in relation to studies in the ambient atmosphere. The four toluene addition experiments in this study were performed at different [tol]o/[NOx]o ratios and displayed an average SOA %yield (in

  1. Divergent effects of transformational and passive leadership on employee safety.

    Science.gov (United States)

    Kelloway, E Kevin; Mullen, Jane; Francis, Lori

    2006-01-01

    The authors concurrently examined the impact of safety-specific transformational leadership and safety-specific passive leadership on safety outcomes. First, the authors demonstrated via confirmatory factor analysis that safety-specific transformational leadership and safety-specific passive leadership are empirically distinct constructs. Second, using hierarchical regression, the authors illustrated, contrary to a stated corollary of transformational leadership theory (B. M. Bass, 1997), that passive leadership contributes incrementally to the prediction of organizationally relevant outcomes, in this case safety-related variables, beyond transformational leadership alone. Third, further analyses via structural equation modeling showed that both transformational and passive leadership have opposite effects on safety climate and safety consciousness, and these variables, in turn, predict safety events and injuries. Implications for research and application are discussed. PMID:16551176

  2. Chemical separation and nuclear transmutation of by-product actinides

    International Nuclear Information System (INIS)

    The paper presents the most important results and conclusions of the assessment studies carried out by the Joint Research Centre-Ispra and by other organizations on the advanced waste disposal strategy based on chemical separation of By-product Actinides (BPA's) from high level liquid waste (HLLW) and their transmutation in nuclear reactors. The technological developments required for the implementation of this strategy have been identified: they concern mainly fuel reprocessing, BPA recovery from all important waste streams and fuel refabrication. After consideration of different strategies for BPA transmutation, the homogeneous recycling in FBR's appears to be most suitable due to its transmutation rate and the compatibility of BPA's with its fuel cycle. The fuel cycle with transmutation has been compared with an advanced reference fuel cycle on the basis of costs and risks. The large effort required for the development and implementation of this new fuel cycle, the increased costs operating the fuel cycle compared with the marginal benefits in the long-term risk of geological disposal, make this strategy not very attractive

  3. Synthesis of Bulk BC8 Silicon Allotrope by Direct Transformation and Reduced-Pressure Chemical Pathways.

    Science.gov (United States)

    Kurakevych, Oleksandr O; Le Godec, Yann; Crichton, Wilson A; Guignard, Jérémy; Strobel, Timothy A; Zhang, Haidong; Liu, Hanyu; Coelho Diogo, Cristina; Polian, Alain; Menguy, Nicolas; Juhl, Stephen J; Gervais, Christel

    2016-09-01

    Phase-pure samples of a metastable allotrope of silicon, Si-III or BC8, were synthesized by direct elemental transformation at 14 GPa and ∼900 K and also at significantly reduced pressure in the Na-Si system at 9.5 GPa by quenching from high temperatures ∼1000 K. Pure sintered polycrystalline ingots with dimensions ranging from 0.5 to 2 mm can be easily recovered at ambient conditions. The chemical route also allowed us to decrease the synthetic pressures to as low as 7 GPa, while pressures required for direct phase transition in elemental silicon are significantly higher. In situ control of the synthetic protocol, using synchrotron radiation, allowed us to observe the underlying mechanism of chemical interactions and phase transformations in the Na-Si system. Detailed characterization of Si-III using X-ray diffraction, Raman spectroscopy, (29)Si NMR spectroscopy, and transmission electron microscopy are discussed. These large-volume syntheses at significantly reduced pressures extend the range of possible future bulk characterization methods and applications. PMID:27532223

  4. Application of nuclear track microfilters to clarification of ultra pure chemical reagents

    International Nuclear Information System (INIS)

    A pilot study of the microfilter to clarify three kinds of chemical reagents (hydrogen peroxide, hydrochloric acid and a negative photoresist for developer)was carried out. They came up to the BVI and MOS standard of ultra pure chemical reagents. It was shown that the self-made nuclear track microfilters could be used in industrial production of ultra pure chemical reagents

  5. The local transformation of the chemical structures induced in polymer by heavy ion-beam irradiation: the characterization of ion in the interaction with material-

    International Nuclear Information System (INIS)

    The local transformations of the chemical structure induced in low density polyethylene (LDPE) by ion-beams with different characteristics are investigated by using micro-FT-IR system. On irradiation by heavier ions than H+, the remarkable LET effect is found in the transformation of the trans-vinylene and the end-vinyl groups. This can not be found on irradiation by H+. Moreover, an importance of the charge number in calculation of the stopping power is pointed out. (author)

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

    International Nuclear Information System (INIS)

    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)

  8. Chemical and biological investigations of a transformer accident at Binghamton, NY

    Science.gov (United States)

    O'Keefe, Patrick W.; Silkworth, Jay B.; Gierthy, John F.; Smith, Robert M.; DeCaprio, Anthony P.; Turner, James N.; Eadon, George; Hilker, David R.; Aldous, Kenneth M.; Kaminsky, Laurence S.; Collins, Doris N.

    1985-01-01

    A transformer fire occurred in a state office building in Binghamton, NY on February 5, 1981. Particulates from inside surfaces of ceiling panels on 16 of the 17 floors had concentrations of polychlorinated dibenzofurans (PCDFs) ranging from < 1 part per million (ppm) to 1200 ppm while polychlorinated biphenyl (PCB) concentrations varied from 28 ppm to 23,000 ppm. In spite of the wide variations in contaminant concentrations, complete analytical data from 11 floors showed that there was a consistent PCDF/PCB ratio (0.067 ± 0.026) and also consistent PCDF isomer group distributions (tetra-CDFs, 33 ± 5%; penta-CDFs, 40 ± 3%; hexa-CDFs, 18 ± 7%; hepta-CDFs, 6 ± 3%). It was found that the particulate samples could be successfully ranked in order of their degree of chemical contamination by an in vitro bioassay. The bioassay was based on induction of keratinization or changes in morphology in mouse epithelial cells. Animal toxicology experiments were carried out with a soot sample containing a PCDF concentration which approximated the mean value found on the ceiling particulates. The single dose oral LD values of the soot and its benzene extract equivalent, each administered to female guinea pigs in 0.75% methyl cellulose, were 410 and 327 mg/kg, respectively. These results demonstrated that the soot matrix had virtually no effect on the toxicity of the chemical contaminants in the soot. Morphological alterations in liver tissues from animals receiving the soot were found after examination by electron and light microscopy. Rabbits dermally exposed to the soot and its benzene extract at 500 mg/kg showed evidence of hypertrophy of centrilobular hepatocytes. In addition the rabbits exposed to the soot extract had a local inflammatory reaction at the site of application. In a subchronic feeding experiment carried out for 90 days with guinea pigs, the lowest effect level was found with an accumulated dose of 1.2 mg soot/kg. The observed effects included salivary gland

  9. Effect of Transforming Viruses on Molecular Mechanisms Associated With Cancer

    OpenAIRE

    DAYARAM, TAJHAL; Marriott, Susan J.

    2008-01-01

    Viruses have been linked to approximately 20% of all human tumors worldwide. These transforming viruses encode viral oncoproteins that interact with cellular proteins to enhance viral replication. The transcriptional and post-transcriptional effects of these viral oncoproteins ultimately result in cellular transformation. Historically, viral research has been vital to the discovery of oncogenes and tumor suppressors with more current research aiding in unraveling some mechanisms of carcinogen...

  10. 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.

  11. Specifics of chemical etching of vanadium dioxide films in proximity to temperature of phase transformation metal-semiconductors

    International Nuclear Information System (INIS)

    A study was made on kinetics and mechanism of chemical etching of vanadium dioxide films in aqueous media (HNO3, HCl, HClO4, C2H2O4, KMnO4, FeCl3 solutions) close by the temperature of metal-semiconductor phase transformation. It is shown that phenomenon of abnormal increase of dissolution rate in the vicinity of temperature of metal-semiconductor phase transformation is typical for the process of chemical etching of vanadium dioxide films in acid media. Reduction of hydrogen ions takes place on vanadium dioxide at t>ttrans

  12. Radiation and chemical effects on viral transformation and tumor antigen expression. Annual progress report, August 1, 1978--May 1, 1979

    International Nuclear Information System (INIS)

    Studies aimed at the biological, biochemical, and immunologic characterization of fetal antigens (EA) in hamsters and mice and locating and determining the distribution of fetal antigens in tumor tissues and in developing fetuses have been underway for several months. Progress has been made in isolating embryonic or fetal antigens from fetuses and from tumor cells. We have developed and reported a reliable lymphocyte transformation assay (LTA) which meets our needs in routinely assaying cell free tumor associated antigen (TAA) preparations from fetal and tumor cells. The assay correlated with transplantation resistance assays and has appropriate specificity. We have also developed the staph-A protein binding assay utilizing anti-serum derived against embryonic antigens present on SV40 tumor cells. In other studies, we have reported increases and perturbations in thymocytes during viral and chemical oncogenesis in hamsters, have developed a simple technique for preserving functional lymphocytes sensitized against TAA by freezing for use in our model system work, have reported the cross-reactivity of tranplantation resistance antigen on a spectrum of chemically induced tumors previously believed to only contain individually specific TSTAs and have recently reported the cross-reactivity of papovavirus induced transplantation resistance antigen in sarcoma cells induced by different viruses. We have concluded our studies of glycosyltransferases in the membranes of developing fetuses and noted no differences in their levels with advancing days of gestation using whold embryo cell populations

  13. Mechano-chemical spinodal decomposition: A phenomenological theory of phase transformations in multi-component, crystalline solids

    CERN Document Server

    Rudraraju, Shiva; Garikipati, Krishna

    2015-01-01

    We present a new phenomenological treatment of phase transformations in multi-component crystalline solids driven by free energy density functions that are non-convex in mechanical and chemical variables. We identify the mechano-chemical spinodal as the region in strain-composition space where the free energy density function is non-convex. Our treatment describes diffusional phase transformations that are accompanied by symmetry breaking structural changes of the crystal unit cell due to mechanical instabilities in the mechano-chemical spinodal. This approach is relevant to phase transformations wherein the structural order parameters can be expressed as linear combinations of strains relative to a high-symmetry reference crystal. Because the local strains in an inhomogeneous, transforming microstructure can be finite, the elasticity problem must account for geometric nonlinearity. Furthermore, for physical consistency and mathematical well-posedness, we regularize the free energy density functions by interf...

  14. Nuclear lattice model and the electronic configuration of the chemical elements

    OpenAIRE

    Garai, Jozsef

    2011-01-01

    The fundamental organizing principle resulting in the periodic table is the nuclear charge. Arranging the chemical elements in an increasing atomic number order, a symmetry pattern known as the Periodic Table is detectable. The correlation between nuclear charge and the Periodic System of the Chemical Elements (PSCE) indicates that the symmetry emerges from the nucleus. Nuclear symmetry can only exist if the relative positions of the nucleons in the nucleus are invariant. Pauli exclusion prin...

  15. Classification of toxic chemical-waste streams from nuclear reactors

    International Nuclear Information System (INIS)

    The radiological and chemical constituents from light water reactors are identified, the methodology for comparing the hazards of various chemicals quantitatively with those of radioactive materials is presented, and the possible management basis of low-level waste (LLW) is considered

  16. The Effect of Windings on ADSL Transformer Insertion Losses

    Institute of Scientific and Technical Information of China (English)

    JIANG Xiao-na; LAN Zhong-wen; CHEN Sheng-ming; ZHANG Huai-wu; SU Hua

    2007-01-01

    Insertion loss (IL) is one of the important parameters of asymmetrical digital subscriber loop (ADSL) transformers. In different frequency bands, the factors that affect insertion loss are different. Windings mainly affect insertion loss in mid and high frequency bands.The effects of winding ways, winding wire diameter and winding turns on insertion loss were discussed. The presented experiment shows that the insertion loss of an ADSL transformer could be under 0.4 dB in mid frequency band when the winding is 30 turns, in which the ADSL transformer satisfies the requirement of total harmonic distortion (THD). Our experiments also show that the sandwich winding structure is better than the side by side winding structure and the twisted-pair winding structure, and the increase of winding diameter is one means to reduce insertion losses of an ADSL transformer in mid frequency band.

  17. Significance of chemical return in nuclear steam generators

    International Nuclear Information System (INIS)

    A reasonable understanding of PWR steam generator corrosion mechanisms such as denting and wastage has been developed, and adequate chemistry control programs defined to obviate the magnitude and effects of these modes of attack. However, relatively unique corrosion attack modes have been encountered at several plants notwithstanding the presence of a reasonable to very good chemistry control program when considered in light of the Steam Generator Owners Group chemistry guidelines. The uniqueness of attack also suggests that parameters not routinely measured or monitored may be playing a significant role. In the authors opinions, the only reasonable method of routinely identifying corrosion accelerating species present in crevices, sludge piles, and deposits in PWR steam generators is by performing detailed chemical return studies during power transients, shutdowns, and long term layups. Although it would be preferable to obtain samples from regions of attack, such samples generally are not available for obvious reasons

  18. Physico-chemical characteristics affect the spatial distribution of pesticide and transformation product loss to an agricultural brook.

    Science.gov (United States)

    Gassmann, M; Olsson, O; Stamm, C; Weiler, M; Kümmerer, K

    2015-11-01

    Diffuse entry of pesticide residues from agriculture into rivers is spatially unevenly distributed. Therefore, the identification of critical source areas (CSAs) may support water quality management in agricultural catchments. In contrast to former studies, we followed the hypothesis that not only hydrological and topographical characteristics but also physico-chemical properties of pesticide residues have a major influence on their loss to rivers and on corresponding formation of CSAs. We designed a virtual experiment, i.e. a numerical experiment as close as possible to environmental conditions, in a headwater catchment where pronounced spatial differences in hydrological transport processes were identified in the past. 144 scenarios with different combinations of adsorption coefficients (KOC = 10-1000 ml/g) and transformation half-lives (DT50 = 3-60 days) for pesticide parent compounds (PCs) and their transformation products (TPs) were simulated using the catchment-scale spatially distributed reactive transport model ZIN-AgriTra. Export fractions of substances in the virtual experiment ranged from 0.001-15% for pesticides and 0.001-1.8% for TPs. The results of the scenario investigations suggest that more of the calculated export mass variability could be attributed to KOC than to DT50 for both PCs and TPs. CSAs for TPs were spatially more equally distributed in the catchment than for PC export which was likely an effect of changing physico-chemical properties during transformation. The ranking of highest export fields was different between PCs and TPs for most of the investigated scenarios but six fields appeared among the top ten export fields in 95% of the scenarios, which shows the influence of site characteristics such as tile drains or soil properties in the catchment. Thus, the highest export fields were determined by a combination of site characteristics and substance characteristics. Therefore, despite the challenge of widely differing physico-chemical

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

    International Nuclear Information System (INIS)

    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.

  20. Interpenetrating Metal-Metalloporphyrin Framework for Selective CO2 Uptake and Chemical Transformation of CO2.

    Science.gov (United States)

    Gao, Wen-Yang; Tsai, Chen-Yen; Wojtas, Lukasz; Thiounn, Timmy; Lin, Chu-Chieh; Ma, Shengqian

    2016-08-01

    Herein we report a robust primitive cubic (pcu)-topology metal-metalloporphyrin framework (MMPF), MMPF-18, which was constructed from a ubiquitous secondary building unit of a tetranuclear zinc cluster, Zn4(μ4-O)(-COO)6, and a linear organic linker of 5,15-bis(4-carboxyphenyl)porphyrin (H2bcpp). The strong π-π stacking from porphyrins and the lengthy H2bcpp ligand affords a 4-fold-interpenetrating network along with reduced void spaces and confined narrow channels. Thereby, MMPF-18 presents segmented pores and high-density metalloporphyrin centers for selective CO2 uptake over CH4 and size-selective chemical transformation of CO2 with epoxides forming cyclic carbonates under ambient conditions. PMID:27337152

  1. ENGAGEMENT OF THE SERBIAN ARMY IN HELPING CIVILIANS IN THE EVENT OF NUCLEAR AND CHEMICAL ACCIDENTS

    OpenAIRE

    INDJIC DEJAN R.; TERZIC MIROSLAV R.; ZIGIC STEVAN V.; RUTIC SRDJAN Z.

    2015-01-01

    Nuclear and chemical accidents in modern society often cause devastating consequences to people, material resources and the environment. This kind of accident requires special procedures and activities during the elimination of the consequences, because of the specific characteristics of highly toxic substances used in nuclear and chemical plants. The Serbian Army with its units and organizations can contribute significantly to the implementation of tasks of eliminating the consequences of su...

  2. Chemical effects of Lγ4 emission spectra

    International Nuclear Information System (INIS)

    Highlights: • The Lγ4 spectra differ depending on the chemical environment of the lanthanides. • The Ce Lγ4 is ligand-dependent. • The Sm Lγ4 and Eu Lγ4 are valence-dependent with chemical shifts of 4–5 eV. • The Yb Lγ4 + Lγ4' depends on both the valency and ligands. - Abstract: An overview of the chemical effects of the Lγ4 (L1O2,3) emission of Ce, Sm, Eu, and Yb is reported. The Lγ4 emission spectra differ significantly depending on the chemical environment of the lanthanides. The emission from the early lanthanide Ce is ligand-dependent, whereas the emission from the middle lanthanides, Sm and Eu, is valence-dependent with chemical shifts of 4–5 eV. The emission from the late lanthanide Yb, which exhibits Lγ4 and Lγ4' bands, depends on both the valency and the coordination environment. Thus, Lγ4 emission is a potentially useful probe that can be used to evaluate the chemical states of lanthanides, in particular, the oxidation numbers of middle to late lanthanides in mixed-valence compounds

  3. Prediction of the rates of chemical transformation of sodium fire aerosols

    International Nuclear Information System (INIS)

    Sodium fires resulting from accidental releases of liquid sodium from a liquid metal fast breeder reactor (LMFBR) would produce aerosols consisting of oxides of sodium, which would tend to react with available water vapor and carbon dioxide. The hydroxide aerosol particles thus formed would be particularly corrosive and hazardous likely exceeding the U.S. industrial hygiene threshold limit value of 2 mg/m3. Reaction of the hydroxide with carbon dioxide to form the carbonate would make the aerosol substantially less hazardous chemically. The analysis of Clough and Garland is extended to study the rates of transformation of the oxides to hydroxide and the hydroxide to the carbonate, assuming that mass transfer is limiting. The cases studied here are gas-phase transport to solid or liquid particles and the transport within particles which are liquids, solids, or agglomerates. For sodium fire aerosols less than 10 micrometers in diameter, mass-transfer rates in air are sufficiently fast that the particles should be converted to the carbonate within seconds, except those particles which are solid or have a solid shell (and are larger than 1 micrometer). Such non-porous particles would be expected only if the aerosol passes through a liquid state during or after agglomeration, due to melting or the absorption of water

  4. 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.

  5. Effective Chemical Inactivation of Ebola Virus

    Science.gov (United States)

    Haddock, Elaine; Feldmann, Friederike

    2016-01-01

    Reliable inactivation of specimens before removal from high-level biocontainment is crucial for safe operation. To evaluate efficacy of methods of chemical inactivation, we compared in vitro and in vivo approaches using Ebola virus as a surrogate pathogen. Consequently, we have established parameters and protocols leading to reliable and effective inactivation. PMID:27070504

  6. Effective Chemical Inactivation of Ebola Virus.

    Science.gov (United States)

    Haddock, Elaine; Feldmann, Friederike; Feldmann, Heinz

    2016-07-01

    Reliable inactivation of specimens before removal from high-level biocontainment is crucial for safe operation. To evaluate efficacy of methods of chemical inactivation, we compared in vitro and in vivo approaches using Ebola virus as a surrogate pathogen. Consequently, we have established parameters and protocols leading to reliable and effective inactivation. PMID:27070504

  7. Kinetics of Syrian hamster cells during x-irradiation enhancement of transformation in vitro by chemical carcinogen

    International Nuclear Information System (INIS)

    The x-irradiation of cultured Syrian hamster cells followed by exposure to a chemical carcinogen after seeding for colony formation results in an enhancement of transformation ordinarily associated with the chemical. Maximum enhancement occurred when 48 hr separated the two treatments and when 250 R was used. With different concentrations of benzo(a)pyrene (0.1-5 μg/ml medium) a similar factor of enhancement was obtained with 250 R, which averaged 8.35, implying that the irradiation pretreatment caused a constant multiplying factor. These results are consistent with the interpretation that transformation occurs through interactions in keeping with a one-hit hypothesis. The transitory effect of irradiation and the lack of transformation with irradiation alone argues against the selection of a special radiation-sensitive cell. At the time of maximum enhancement (48 hr), the cell cycles of irradiated and nonirradiated cells do not differ. The addition of benzo(a)pyrene to irradiated cells does not alter the number of cells capable of synthesizing DNA or the flow of cells from G1 to S. The number of cells accumulated in mitosis also does not appear to differ between irradiated and nonirradiated cultures treated with 2.5 μg benzo(a)pyrene. Chromosome aberrations or alterations in ploidy cannot account for the significant increase in enhancement observed at 48 hr postirradiation; however, twice as many cells with chromosome or chromatid gaps were found at 48 hr as compared to either 24 or 72 hr postirradiation

  8. Physical and Chemical Transformation of Hydroxyapatite Nanoparticles in Aqueous Sol after Preparation and in vitro

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The co-precipitation method followed by ultrasound and heat treatment is a common way to prepare below 100 nm sized hydroxyapatite nanoparticles for biomedical studies and applications. The size and pH value of the obtained calcium phosphate nanoparticles in aqueous sol have a strong impact on the interactions with cells and tissue. The physical and chemical properties of material samples for in vitro and in vivo studies are often assumed to remain constant from the time after fabrication to the actual use. Only little attention is paid to eventual changes of the material over time or due to the different in vitro conditions. In this study, the physical and chemical transformation of calcium phosphate nanoparticles after preparation and in vitro was investigated. As the result showed, dispersed nano sized amorphous calcium phosphate precipitation as well as crystallized hydroxyapatite nanoparticles continue to crystallize even when kept at 4 ℃ leading to declining pH values and particle sizes.Due to the pH buffer in the medium the pH value of the cell culture remained stable after adding 20% nanoparticle sol in vitro. However, hydroxyapatite nanoparticles immediately became unstable in the presents of cell culture medium. The resulting loose agglomerations showed a size of above 500 nm.

  9. 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.

  10. Chemical and nuclear properties of Rutherfordium (Element 104)

    International Nuclear Information System (INIS)

    The chemical-properties of rutherfordium (Rf) and its group 4 homologs were studied by sorption on glass support surfaces coated with cobalt(II)ferrocyanide and by solvent extraction with tributylphosphate (TBP) and triisooctylamine (TIOA). The surface studies showed that the hydrolysis trend in the group 4 elements and the pseudogroup 4 element, lb, decreases in the order Rf>Zr∼Hf>Th. This trend was attributed to relativistic effects which predicted that Rf would be more prone to having a coordination number of 6 than 8 in most aqueous solutions due to a destabilization of the 6d5/2 shell and a stabilization of the 7pl/2 shell. This hydrolysis trend was confirmed in the TBP/HBr solvent extraction studies which showed that the extraction trend decreased in the order Zr>Hf>Rf?Ti for HBr, showing that Rf and Ti did not extract as well because they hydrolyzed more easily than Zr and Hf. The TIOA/HF solvent extraction studies showed that the extraction trend for the group 4 elements decreased in the order Ti>Zr∼Hf>Rf, in inverse order from the trend of ionic radii Rf>Zr∼Hf>Ti. An attempt was made to produce 263Rf (a) via the 248Cm(22Ne, α3n) reaction employing thenoyltrifluoroacetone (TTA) solvent extraction chemistry and (b) via the 249Bk(18O,4n) reaction employing the Automated Rapid Chemistry Apparatus (ARCA). In the TTA studies, 16 fissions were observed but were all attributed to 256Fm. No alpha events were observed in the Rf chemical fraction. A 0.2 nb upper limit production cross section for the 248Cm(22Ne, α3n)263Rf reaction was calculated assuming the 500-sec half-life reported previously by Czerwinski et al. [CZE92A

  11. 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.

  12. Effective citizen advocacy of beneficial nuclear technologies

    International Nuclear Information System (INIS)

    In 1991, a small group of citizens from communities near the Savannah River Site (SRS) formed a pro-nuclear education and advocacy group, Citizens for Nuclear Technology Awareness (CNTA). Their purpose was to: (1) counter nuclear misinformation that dominated the nation's news outlets, (2) provide education on nuclear subjects to area citizens, students, elected officials, and (3) provide informed citizen support for potential new missions for SRS when needed. To effectively accomplish these objectives it is also essential to establish and maintain good relations with community leaders and reporters that cover energy and nuclear subjects. The organization has grown considerably since its inception and has expanded its sphere of influence. We believe that our experiences over these fifteen years are a good model for effectively communicating nuclear subjects with the public. This paper describes the structure, operation and some of the results of CNTA. (authors)

  13. UK Chemical Nuclear Data Committee: progress report

    International Nuclear Information System (INIS)

    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)

  14. Characterization of nuclear decontamination solutions at the Idaho Chemical Processing Plant from 1982-1990

    International Nuclear Information System (INIS)

    This report represents possibly the single largest collection of operational decontamination data from a nuclear reprocessing facility at the Idaho National Engineering Laboratory and perhaps anywhere in the world. The uniqueness of this data is due to the Idaho Chemical Processing Plant's (ICPP's) ability to process different types of highly enriched nuclear fuel. The report covers an 8-year period, during which six campaigns were conducted to dissolve nuclear fuel clad in stainless steel, aluminum, graphite, and zirconium. Each fuel type had a separate head-end process with unique dissolution chemistry, but shared the same extraction process equipment. This report presents data about decontamination activities of the ICPP's First Cycle extraction vessels, columns, piping, and aluminum dissolution vessels. Operating data from 1982 through 1990 has been collected, analyzed, and characterized. Chemicals used in the decontamination processes are documented along with quantities used. The chemical solutions are analyzed to compare effectiveness. Radioisotopic analysis is recorded, showing and quantifying what nuclides were removed by the various solutions. The original data is also provided to make it possible for researchers to address questions and test other hypotheses not discussed in this report

  15. Characterization of nuclear decontamination solutions at the Idaho Chemical Processing Plant from 1982-1990

    Energy Technology Data Exchange (ETDEWEB)

    Zohner, S.K.

    1996-03-01

    This report represents possibly the single largest collection of operational decontamination data from a nuclear reprocessing facility at the Idaho National Engineering Laboratory and perhaps anywhere in the world. The uniqueness of this data is due to the Idaho Chemical Processing Plant`s (ICPP`s) ability to process different types of highly enriched nuclear fuel. The report covers an 8-year period, during which six campaigns were conducted to dissolve nuclear fuel clad in stainless steel, aluminum, graphite, and zirconium. Each fuel type had a separate head-end process with unique dissolution chemistry, but shared the same extraction process equipment. This report presents data about decontamination activities of the ICPP`s First Cycle extraction vessels, columns, piping, and aluminum dissolution vessels. Operating data from 1982 through 1990 has been collected, analyzed, and characterized. Chemicals used in the decontamination processes are documented along with quantities used. The chemical solutions are analyzed to compare effectiveness. Radioisotopic analysis is recorded, showing and quantifying what nuclides were removed by the various solutions. The original data is also provided to make it possible for researchers to address questions and test other hypotheses not discussed in this report.

  16. Effect of Chemical Reagents in Foam Decontamination

    International Nuclear Information System (INIS)

    The decontamination foam comprises at least one surfactant to generate the foam and one or more chemical reactants to achieve the dissolution of the contaminants at the solid surface. In order to improve the efficiency of decontamination foam, the present study attempts to find the optimum condition of chemical reagents to the foaming solution. This paper deals with understanding the effects of chemical reagents involved in foam decontamination efficiency, evaluation of side effect on foam stability and finally the improvement brought by formulation science. Basic experiments using the nanoparticle-based complex fluid decontamination foam have been performed in order to development of decontamination foam technology. Results show that in the case of coexistence of chemical reagents, for the purpose of the good foam ability and foam stability, it is necessary to increase the concentration of surfactant. In corrosion test, metal materials including carbon steel, stainless steel 304, aluminum, inconel 600 and cupper, generally corrosion solubility percent in nitric acid solution were higher than in phosphoric acid solution. Bench-scale testing was used to evaluate the efficacy of three decontamination formulations on contaminant carbon steel component of dry oven. The results shows decontamination factor was in the range of 6.1∼13.4. Results suggest that our foam formulations have a feasibility potential to removal of about 83∼93% total radioactivity in contaminant

  17. Effect of Chemical Reagents in Foam Decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Han Beom; Yoonm Inho; Jung, Chonghun; Choi, Wangkyu [Korea Atomic Energy research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The decontamination foam comprises at least one surfactant to generate the foam and one or more chemical reactants to achieve the dissolution of the contaminants at the solid surface. In order to improve the efficiency of decontamination foam, the present study attempts to find the optimum condition of chemical reagents to the foaming solution. This paper deals with understanding the effects of chemical reagents involved in foam decontamination efficiency, evaluation of side effect on foam stability and finally the improvement brought by formulation science. Basic experiments using the nanoparticle-based complex fluid decontamination foam have been performed in order to development of decontamination foam technology. Results show that in the case of coexistence of chemical reagents, for the purpose of the good foam ability and foam stability, it is necessary to increase the concentration of surfactant. In corrosion test, metal materials including carbon steel, stainless steel 304, aluminum, inconel 600 and cupper, generally corrosion solubility percent in nitric acid solution were higher than in phosphoric acid solution. Bench-scale testing was used to evaluate the efficacy of three decontamination formulations on contaminant carbon steel component of dry oven. The results shows decontamination factor was in the range of 6.1∼13.4. Results suggest that our foam formulations have a feasibility potential to removal of about 83∼93% total radioactivity in contaminant.

  18. Role of Chemical Driving Force in Martensitic Transformations of High-Purity Fe-Cr-Ni Alloys

    Science.gov (United States)

    Behjati, P.; Najafizadeh, A.

    2011-12-01

    The main objective of the present work is to point out the respective roles of chemical driving force and stacking fault energy (SFE) in the occurrence of martensitic transformations in high-purity Fe-Cr-Ni alloys. For this purpose, the transmission electron microscope (TEM), X-ray diffractometer, thermal differential microanalyzer (TDA), and tension test were employed to report M s temperatures, austenite stacking fault energies, and driving forces for the concerned alloys. It was observed that the martensitic transformations in the studied alloys occur through the γ → ɛ → α' steps. As a remarkable result, it was shown that a low SFE, if necessary to ɛ-phase nucleation, is not a sufficient condition for nucleation of α' phase. In fact, the formation of stable α' nuclei from α' embryos occur if the required chemical driving force is provided. Also, an equation was proposed for the kinetics of spontaneous martensitic transformation as a function of driving force.

  19. Chemical Modifications of Starch: Microwave Effect

    OpenAIRE

    2015-01-01

    This paper presents basic methods of starch chemical modification, the effect of microwave radiation on the modification process, and the physicochemical properties of starch. It has been shown that the modifications contribute to improvement of the material performance and likewise to significant improvement of its mechanical properties. As a result, more and more extensive use of starch is possible in various industries. In addition, methods of oxidized starch and starch esters preparation ...

  20. The radiation effects of nuclear weapons explosions

    International Nuclear Information System (INIS)

    The energy resulting from nuclear weapons explosions consists of thermal energy (heat radiation), shock waves, initial radiation (nuclear ray flash, gamma and neutron flash), and nuclear radiation of the fission products (fallout). The contribution of the different energy components depends on the energy amounts produced by fission or fusion reactions (A-weapon, H-weapon), on the components used for conversion to helium-4 (deuterium, tritium, lithium), the weapon design (radiation absorption and induced activity in auxiliaries), and on the type of employment (atmospheric, ground, or underground explosion). The damaging effects vary accordingly, consisting of thermal damage, blast effects, and radiation injuries. The effects are explained and compared. (orig.)

  1. Widespread after-effects of nuclear war

    International Nuclear Information System (INIS)

    Radioactive fallout and depletion of the ozone layer, once believed catastrophic consequences of nuclear war, are now proved unimportant in comparison to immediate war damage. Today, ''nuclear winter'' is claimed to have apocalyptic effects. Uncertainties in massive smoke production and in meteorological phenomena give reason to doubt this conclusion. (author)

  2. The environmental effects of nuclear war

    International Nuclear Information System (INIS)

    Substantial environmental disruption will significantly add to the disastrous consequences caused by the direct thermal, blast, and radiological effects brought on by a major nuclear war. Local fallout could cover several percent of the Northern Hemisphere with potentially lethal doses. Smoke from post-nuclear fires could darken the skies and induce temperature decreases of tens of degrees in continental interiors. Stratospheric ozone could be significantly reduced due to nitric oxide injections and smoke-induced circulation changes. The environmental effects spread the consequences of a nuclear war to the world population, adding to the potentially large disruptive effects a further reason to avoid such a catastrophe. 27 refs., 4 figs

  3. IEEE Std 638-1992: IEEE standard for qualification of Class 1E transformers for nuclear power generating stations

    International Nuclear Information System (INIS)

    Procedures for demonstrating the adequacy of new Class 1E transformers, located in a mild environment of a nuclear power generating station, to perform their required safety functions under postulated service conditions, are presented. Single and three phase transformers rated 601 V to 15,000 V for the highest voltage winding and up to 2,500 kVA (self-cooled rating) are covered. Because of the conservative approach used in the development of this new standard for new transformers, the end point criteria cannot be used for in-service transformers

  4. Automation of the chemical treatment plant of radioactive wastes at the RACSO Nuclear Center

    International Nuclear Information System (INIS)

    The RACSO Nuclear Center has a chemical treatment plant which has been designed and built for the low and medium activity radioactive residual treatment. Considering the Radiological Security standards and the optimization principle in order to reduce the doses of the operator personnel, the chemical treatment plant automation development was carried out

  5. Study of the martensitic phase transformation in Ni-Ti by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    In order to study the microscopic mechanisms underlying the martensitic phase transformations (MPT), nuclear magnetic resonance (NMR) experiments have been performed on NiTi shape memory alloys displaying a two-step transformation using the 61Ni-nuclei as microscopic probes. Systematic measurements of the spectral linewidths and Knight shifts as a function of temperature for polycrystalline Ti-50.6 at.% Ni wires and Ti-rich Ni-Ti thin films have been carried out. The volume fraction of martensite and R-phase at each temperature can then be determined by spectral deconvolution. The growth curve of martensite as obtained by NMR provides quantitative information that cannot be detected by other experimental techniques. It has been shown in the Ni-Ti wire sample that 5% of the austenite remains untransformed even at a temperature well below Mf as determined by differential scanning calorimetry. In contrast to the austenite, all the R-phase transforms into martensite. In the Ni-Ti thin films an additional spectral contribution is detected. Its origin is tentatively attributed to the presence of a supplementary phase which has been identified as Ti2Ni precipitates by TEM observations. (orig.)

  6. Study of the martensitic phase transformation in Ni-Ti by nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Crevoiserat, S.; Scherrer, P. [Ecole Polytechnique Federale, Lausanne (Switzerland). Inst. de Genie Atomique; Dimitropoulos, C. [Institut de Physique Experimentale, Ecole Polytechnique Federale de Lausanne, CH-1015, Lausanne (Switzerland); Gotthardt, R. [Institut de Genie Atomique, Departement de Physique (DP), Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015, Lausanne (Switzerland)

    1999-12-15

    In order to study the microscopic mechanisms underlying the martensitic phase transformations (MPT), nuclear magnetic resonance (NMR) experiments have been performed on NiTi shape memory alloys displaying a two-step transformation using the {sup 61}Ni-nuclei as microscopic probes. Systematic measurements of the spectral linewidths and Knight shifts as a function of temperature for polycrystalline Ti-50.6 at.% Ni wires and Ti-rich Ni-Ti thin films have been carried out. The volume fraction of martensite and R-phase at each temperature can then be determined by spectral deconvolution. The growth curve of martensite as obtained by NMR provides quantitative information that cannot be detected by other experimental techniques. It has been shown in the Ni-Ti wire sample that 5% of the austenite remains untransformed even at a temperature well below M{sub f} as determined by differential scanning calorimetry. In contrast to the austenite, all the R-phase transforms into martensite. In the Ni-Ti thin films an additional spectral contribution is detected. Its origin is tentatively attributed to the presence of a supplementary phase which has been identified as Ti{sub 2}Ni precipitates by TEM observations. (orig.)

  7. Effect of nuclear education on public attitude

    International Nuclear Information System (INIS)

    A method is proposed to assess the effect of nuclear education. In this method, the nuclear education is treated as a part of the activities for public acceptance (PA), and a unit PA activity is assumed to give the same effect on the public, in essence, as a unit of nuclear information given by the newsmedia. Moreover, the change of attitude to nuclear energy is assumed to originate from enhanced understanding which, in turn, is brought by the stimulus given by the nuclear education. With the values of constants determined by using the data in Japan, example calculations were made for the educational time b0 and the infiltration rate of education into minors B as parameters. It became clear from this calculation that the attitude to nuclear energy formed in the age of school children plays an essential role in shaping future public opinion since it is held in individuals without any notable modification for a long time after its formation, and that the effect of nuclear education to minors emerges depending on the variables b0 and B in a highly non-linear manner. It was also found that there exists an optimum condition for nuclear education to attain the maximum amelioration of public opinion under a given condition of man-power for educational workers. (author)

  8. Chemical digestion of low level nuclear solid waste material

    International Nuclear Information System (INIS)

    A method is described for processing low level, light weight, bulky, combustible nuclear solid waste material comprising the steps of reacting said solid waste material with concentrated sulfuric acid at a temperature within the range of 230 deg - 300 deg C and simultaneously, subsequently, or both simultaneously and subsequently contacting said waste with concentrated nitric acid or nitrogen oxides whereby carbonaceous material is oxidized to gaseous byproducts and a low volume residue. (author)

  9. Exhibition of the periodicity of Quantum Fourier Transformation in Nuclear Magnetic Resonance

    CERN Document Server

    Peng, X; Fang, X; Feng, M; Yang, X; Liu, M; Gao, K; Peng, Xinhua; Zhu, Xiwen; Fang, Ximing; Feng, Mang; Yang, Xiaodong; Liu, Maili; Gao, Kelin

    2002-01-01

    The remarkable capability of quantum Fourier transformation (QFT) to extract the periodicity of a given periodic function has been exhibited by using nuclear magnetic resonance (NMR) techniques. Two separate sets of experiments were performed. In a full QFT, the periodicity were validated with state tomography and fidelity measurements. For a simplified QFT, the three-qubit pseudo-pure state was created by introducting an additional observer spin, and the spectra recorded on the observer spin showed intuitively the power of QFT\\ to find the periodicity. Experimentally realizing the QFT provides a critical step to implement the renowned Shor's quantum factoring algorithm and many other algorithms. Moveover, it can be applied to the study of quantum chaos and other quantum information processing.

  10. Atmospheric effects of a nuclear war

    International Nuclear Information System (INIS)

    The subject is discussed under the headings: nuclear war scenario (assumptions of size and place of explosions); fires; urban and forest fires; smoke and soot; darkness; meteorological and climatic effects; photochemical smog; ozone shield depletion; conclusions. (U.K.)

  11. Serum Transforming Growth Factor Beta-1 as an Index of Chemical Hepato carcinogenesis in Rats

    International Nuclear Information System (INIS)

    Transforming growth factor beta-1 (TGF β1) is an important mediator which controls liver cell proliferation and replication. The relation between TGF β1, Alpha-fetoprotein (AFP) and clinically thought hepatocellular carcinoma (HCC) in rats were investigated to clarify the clinical value of measuring peripheral serum TGF β1 and AFP in evaluation of HCC. Peripheral serum TGF β1 and AFP were measured during chemically induced hepato carcinogenesis. Male rats were given a genotoxic compound diethylnitrosamine (DEN) in drinking water for 149 days with control receiving drinking water only. Animals were killed at different times intervals 54, 86 and 149 days, serum TGF β1 levels were measured by, Enzyme Linked Immunosorbent Assay (ELISA) and AFP levels were assayed by immunoradiometric assay (IRMA). In DEN treated rats 54 days, there was mild portal tract inflammatory cellular infiltrate, serum TGF β1 and AFP levels were both significantly elevated above control (P>0.05 and P<0.001). At 86 days there were moderate inflammation (portal and peri portal), serum TGF β1 and AFP levels were significantly increased, (P<0.001). At 149 days typical HCC were present in ten of ten rats and serum TGF β1 and AFP were both significantly elevated compared with controls, (P<0.001). It can be concluded that serum TGF β1 and AFP levels are elevated during chemically induced HCC and have roles during the stages of process (initiation, promotion and progression); both serum TGF β1 and AFP levels can be used in parallel as a non invasive tumor markers for early diagnosis and prognosis of HCC

  12. 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

    differences are due to different conformational behavior of the OH and OCH3 groups; while the ortho-disubstituted OH group remains planar in polyphenols due to hydrogen bonding and conjugative stabilization, the steric congestion in ortho-disubstituted anisoles outweighs the conjugative effects and forces the......Investigation of all O-methyl ethers of 1,2,3-benzenetriol and 4-methyl-1,2,3-benzenetriol (3-16) by 1H NMR spectroscopy and density-functional calculations disclosed practically useful conformational effects on 1H NMR chemical shifts in the aromatic ring. While the conversion of phenol (2) to...... 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...

  13. Sensing of chemical substances using SQUID-based nuclear quadrupole resonance

    International Nuclear Information System (INIS)

    Using a high-Tc radio frequency superconducting quantum interference device (rf SQUID) with a normal metal transformer, we successfully detected the nuclear quadrupole resonance (NQR) at about 888 kHz of 14N in p-nitrotoluene (PNT) at room temperature. Only one coil was used as the resonator coil for the transmission and the pickup coil of the transformer. To reduce the influence of the strong excitation field, cross diodes and switches were inserted in the transformer. The signal-to-noise ratio of the NQR spectrum using high-Tc rf SQUID system was comparable to that of using a low noise preamplifier

  14. Fourier transform nuclear magnetic resonance studies of 25Mg and 43Ca

    International Nuclear Information System (INIS)

    The ratios of the Larmor frequencies of 25Mg and 37Cl and of 43Ca and 37Cl have been measured in aqueous solutions and nuclear magnetic moments are given for these nuclei in the hydrated ions. 25Mg and 43Ca chemical shifts have been investigated at natural abundance of these isotopes in solutions of the chlorides, bromides, nitrates, perchlorates in H2O and D2O. The signal intensities are large enough to study within reasonable time these nuclei at natural abundance down to low concentrated solutions, e.g. 8 millimolal for 25Mg. For 25Mg very small chemical shifts have been observed whereas for 43Ca remarkable shifts to higher frequencies are found for halide solutions and to lower frequencies for the oxyanion solutions. Linewidths of only some Hz have been observed for both isotopes. (orig.)

  15. Microwave-assisted Chemical Transformations

    Science.gov (United States)

    In recent years, there has been a considerable interest in developing sustainable chemistries utilizing green chemistry principles. Since the first published report in 1986 by Gedye and Giguere on microwave assisted synthesis in household microwave ovens, the use of microwaves as...

  16. Electronic equipment and software of the mesooptical Fourier - transform microscope for nuclear emulsion

    International Nuclear Information System (INIS)

    The electronic part of the Mesooptical Fourier-Transform Microscope (MFTM) and the software for the automatic recording of the straight line particle tracks of minimum ionization in nuclear emulsion are described. The features of the data at the output of the MFTM depending on the geometrical position of a straight line particle track and the algorithm of the read-out of this data are given. The units moving the carriages and rotating the platform of the optical interface of the MFTM are described. The programming supplements to the standard FOKAL'71 subroutines used in these experiments as well as the routine programme used for the evaluation of the mesooptical images of straight line particle tracks are presented

  17. Digital implementation of filters for nuclear applications using the discrete wavelet transform

    International Nuclear Information System (INIS)

    This paper presents a novel digital pulse processing technique based on fast implementations of a modern signal analysis method known as the wavelet transform (WT). From the point of view of standard nuclear filtering, the whole analysis may be understood as the action of a bank of gaussian shapers. The algorithm permits the evaluation of relevant parameters on each pulse and, making use of this information, a spectral improvement is achieved in the response of HgI2 detectors constructed in our laboratories. As the performance of these detectors is mainly limited by the hole trapping phenomenon, the introduction of a charge loss correction making use of the WT has been considered. In this work, the pulse processing has been carried out by transferring the digital recorded pulses to a computer where a software version of the algorithm is performed. (orig.)

  18. Probing atomic scale transformation of fossil dental enamel using Fourier transform infrared and nuclear magnetic resonance spectroscopy : a case study from the Tugen Hills (Rift Gregory, Kenya)

    OpenAIRE

    Yi, H. H.; Balan, Etienne; Gervais, C; SEGALEN, L.; Roche, D; PERSON, A.; Fayon, F.; Morin, G.; F. Babonneau

    2014-01-01

    A series of fossil tooth enamel samples was investigated by Fourier transform infrared (FTIR) spectroscopy, C-13 and F-19 magic-angle spinning nuclear magnetic resonance (MAS NMR) and scanning electron microscopy (SEM). Tooth remains were collected in Mio-Pliocene deposits of the Tugen Hills in Kenya. Significant transformations were observed in fossil enamel as a function of increasing fluorine content (up to 2.8 wt.%). FTIR spectroscopy revealed a shift of the nu(1) PO4 stretching band to h...

  19. Aerosol simulation including chemical and nuclear reactions

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Chemical History with a Nuclear Microprobe

    OpenAIRE

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

  1. Chemical effect in nuclear decay processes. Applications in in situ studies in hot atom chemistry

    International Nuclear Information System (INIS)

    In certain cases, secondary processes, such as X-ray or electron emission initiated by the primary event, do show effects which can be correlated with the chemical state of the emitting atom. The most well known is Moessbauer recoil-less γ-emission, but this talk will concentrate on other, more widespread processes that follow either γ-ray internal conversion (γIC) or electron capture (EC). The former leads to electron emission and the latter to X-ray and Auger electron emission. Such emissions have been extensively studied in non-radioactive situations. These studies have shown that changes in photo- or Auger-electron energy can be readily correlated with valency and that the energies, peak shapes and peak intensities of X-rays that are generated by valence-core transitions show chemically related perturbations. γIC has been applied to the determination of changes of 3p and 3d binding energies as a function of technetium valency. The results are comparable with those from conventional X-ray photoelectron spectroscopy. In X-ray emission spectroscopy (XES) it is the Kα and Kβ X-rays from chromium (51Cr) that have been most extensively studied. Studies in non-radioactive systems for chromium and related first row transition elements seem to indicate that the Kβ/Kα intensity ratio increases with valency. This may be rationalized as due to a greater response by 3p than 2p electrons to a reduction in the number of 3d electrons: 3p becomes more contracted and so the 3p → 1s transition probability is enhanced leading to the relative increase in Kβ intensity. Once 'chemical effects' in γIC and EC:XES have been established for a range of recoil elements they may be used to determine the chemical state of a recoil atom in a solid state matrix without recourse to dissolution. Such a non-invasive procedure will yield invalunable data on the primary hot atom chemistry processes. (author)

  2. Group theory transformation for Soret and Dufour effects on free convective heat and mass transfer with thermophoresis and chemical reaction over a porous stretching surface in the presence of heat source/sink

    Energy Technology Data Exchange (ETDEWEB)

    Kandasamy, R., E-mail: future990@gmail.com [Computational Fluid Dynamics, FSSW, Universiti Tun Hussein Onn Malaysia, 86400 Batu Pahat, Johore (Malaysia); Hayat, T. [Department of Mathematics, Quaid-i-Azam University Islamabad (Pakistan); Department of Mathematics, College of Science, King Saud University, P.O. Box 2455, Riyadh 1451 (Saudi Arabia); Obaidat, S. [Department of Mathematics, College of Science, King Saud University, P.O. Box 2455, Riyadh 1451 (Saudi Arabia)

    2011-06-15

    Highlights: > The group theoretic method is of wide applicability. > Concentration boundary layer is significantly suppressed by the thermophoretic force. > Impact of Soret and Dufour effects in the presence of thermophoresis particle deposition with chemical reaction plays an important role on the flow field. - Abstract: The group theoretic method is applied for solving the problem of combined effect of thermal diffusion and diffusion thermo on free convective heat and mass transfer over a porous stretching surface in the presence of thermophoresis particle deposition with variable stream conditions. The application of one-parameter groups reduces the number of independent variables by one and consequently, the system of governing partial differential equations with the boundary conditions reduces to a system of ordinary differential equations with appropriate boundary conditions. The equations along with the boundary conditions are solved numerically by using Runge Kutta Gill integration scheme with shooting technique. Impact of Soret and Dufour effects in the presence of thermophoresis particle deposition with chemical reaction plays an important role on the flow field. The results thus obtained are presented graphically and discussed.

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

    International Nuclear Information System (INIS)

    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)

  4. Chemical Modifications of Starch: Microwave Effect

    Directory of Open Access Journals (Sweden)

    Kamila Lewicka

    2015-01-01

    Full Text Available This paper presents basic methods of starch chemical modification, the effect of microwave radiation on the modification process, and the physicochemical properties of starch. It has been shown that the modifications contribute to improvement of the material performance and likewise to significant improvement of its mechanical properties. As a result, more and more extensive use of starch is possible in various industries. In addition, methods of oxidized starch and starch esters preparation are discussed. Properties of microwave radiation and its impact on starch (with particular regard to modifications described in literature are characterized.

  5. Radioactive and Other Effects of Nuclear Explosion

    International Nuclear Information System (INIS)

    As a result of long lasting efforts of international community to definitely ban all test nuclear explosions, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was opened for signature in New York on 24 September 1996, when it was signed by 71 states, including Croatia. The State Office for Nuclear Safety (SONS) which, as an independent state regulatory authority has a responsibility for activities relating to nuclear safety, including the national authority over this Treaty, is actively engaged in CTBTO activities. The nuclear explosion causes a lot of effects (blast, thermal, radioactive, electromagnetic) which differs a lot in its nature, reach, lasting and other. The longest lasting aftermath is from the radioactive effects that cause a radioactive fallout and a lot of radioactive elements in the environment, created by the influence of a primary beam of radiation. Fission and fusion are the main source of radionuclide created by the nuclear explosion, and the longest lasting aftermaths are by the fission products, namely their offspring in natural disintegration chains. This can make contaminated areas inappropriate for life for very long periods. Even in the case of underground nuclear explosion (when underground cavity is formed with no effects on the surface), a leakage of radioactive gases through cracks is possible. A number of radionuclide is created by the neutron activation of elements naturally present in an environment, because a very strong neutron radiation appears in the moment of nuclear explosion. The abundance of particular radionuclide is a very much dependent of a place of performing nuclear explosion and a composition of soil or water in the vicinity.(author)

  6. Increased expression and activity of nuclear cathepsin L in cancer cells suggests a novel mechanism of cell transformation.

    Science.gov (United States)

    Goulet, Brigitte; Sansregret, Laurent; Leduy, Lam; Bogyo, Matthew; Weber, Ekkehard; Chauhan, Shyam S; Nepveu, Alain

    2007-09-01

    It is generally accepted that the role of cathepsin L in cancer involves its activities outside the cells once it has been secreted. However, cathepsin L isoforms that are devoid of a signal peptide were recently shown to be present in the nucleus where they proteolytically process the CCAAT-displacement protein/cut homeobox (CDP/Cux) transcription factor. A role for nuclear cathepsin L in cell proliferation could be inferred from the observation that the CDP/Cux processed isoform can accelerate entry into S phase. Here, we report that in many transformed cells the proteolytic processing of CDP/Cux is augmented and correlates with increased cysteine protease expression and activity in the nucleus. Taking advantage of an antibody that recognizes the prodomain of human cathepsin L, we showed that human cells express short cathepsin L species that do not contain a signal peptide, do not transit through the endoplasmic reticulum, are not glycosylated, and localize to the nucleus. We also showed that transformation by the ras oncogene causes rapid increases both in the production of short nuclear cathepsin L isoforms and in the processing of CDP/Cux. Using a cell-based assay, we showed that a cell-permeable inhibitor of cysteine proteases is able to delay the progression into S phase and the proliferation in soft agar of ras-transformed cells, whereas the non-cell-permeable inhibitor had no effect. Taken together, these results suggest that the role of cathepsin L in cancer might not be limited to its extracellular activities but may also involve its processing function in the nucleus. PMID:17855659

  7. Chemical pretreatment of Savannah River Site nuclear waste for disposal

    International Nuclear Information System (INIS)

    This work describes two processes, Extended Sludge Processing and In-Tank Precipitation, which have been developed and demonstrated at full-scale to pretreat the Savannah River Site High-Level Waste for permanent disposal. These processes will be carried out in waste storage tanks which have been modified for chemical processing. These processes will concentrate the radioactivity into a small volume for vitrification. The bulk of the waste will be sufficiently decontaminated such that it can be disposed of as a low-level waste. The decontaminated waste will be incorporated into a cement wasteform in the Saltstone Facility

  8. Chemical sensors for nuclear industry

    International Nuclear Information System (INIS)

    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 H2 sensors in sodium and in cover gas circuit of the Fast breeder reactors for its smooth functioning, NH3 and H2S sensors for use in Heavy water production industries and NOx 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)

  9. Microbial Transformations of Actinides and Other Radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Francis,A.J.; Dodge, C. J.

    2009-01-07

    Microorganisms can affect the stability and mobility of the actinides and other radionuclides released from nuclear fuel cycle and 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 in the environment 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 extensively investigated, we have only limited information on the effects of microbial processes and biochemical mechanisms which affect the stability and mobility of radionuclides. The mechanisms of microbial transformations of the major and minor actinides U, Pu, Cm, Am, Np, the fission products and other radionuclides such as Ra, Tc, I, Cs, Sr, under aerobic and anaerobic conditions in the presence of electron donors and acceptors are reviewed.

  10. Direct chemical characterization of natural wood resins by temperature-resolved and space-resolved Fourier transform infrared spectroscopy

    Science.gov (United States)

    Chen, Jian-bo; Zhou, Qun; Sun, Su-qin

    2016-07-01

    Wood resins are valuable natural products with wide utilizations. Either in the form of resin exudates or in the form of resin-containing woods, natural wood resins are usually complex mixtures consisting of various compounds. Therefore, effective chemical characterization methods are necessary for the research and quality control of natural wood resins. No need for separation or labeling, wood resin samples can be measured directly by Fourier transform infrared (FT-IR) spectroscopy, which reduces the testing costs and avoids the possible distortions caused by the pretreatments. However, the absorption bands of various compositions in the resin sample are assembled in a single spectrum by the separation-free measurement, which makes it difficult to identify the compounds of interest and decreases the limits of detection. In this research, the temperature-resolved and space-resolved FT-IR techniques are proposed to resolve the overlapped signals for the direct, selective, and sensitive characterization of natural wood resins. For resin exudates, the temperature-resolved FT-IR spectroscopy and two-dimensional correlation analysis can resolve the absorption bands of different compounds according to their responses to the thermal perturbations. For resin-containing woods, the FT-IR microspectroscopic imaging and principal component analysis can resolve the absorption bands of different compounds according to their positions. The study of six kinds of wood resins proves the feasibility of temperature-resolved and space-resolved FT-IR techniques for the direct, selective, and sensitive chemical characterization of natural wood resins.

  11. Chemical mitigation of the transmutation problem in crystalline nuclear waste radiophases

    International Nuclear Information System (INIS)

    Certain deleterious effects on a solid nuclear waste form, though not yet quantitatively defined, could occur due to transmutations of the type 137Cs+ → 137Ba2+ and 90Sr2+ → 90Zr4+. The relevant causes of such possible effects are the valence and size changes. In this paper, a chemical mitigation strategy is explicitly formulated: if the transmuting species can be incorporated in a multiple-cation host, in which one of the inert cations is a variable-valence transition metal, the valence-change aspect of transmutation can be mitigated by a complementary valence change of the transition metal ion. The present work involved chemically simulating the transmutation and then attempting to find a Cs- or Sr-bearing single-phase host which would remain single-phase after the transmutation had occurred. Of several structures investigated, perovskite appears to be promising as the A-site can accommodate the approximately 20% size change which occurs when Cs decays to Ba. Ta and Nb were used as the variable-valence ions in the B-site. The application of the results to unpartitioned and partitioned nuclear wastes is discussed. (author)

  12. Chemical and toxicological evaluation of transformation products during advanced oxidation processes.

    Science.gov (United States)

    vom Eyser, C; Börgers, A; Richard, J; Dopp, E; Janzen, N; Bester, K; Tuerk, J

    2013-01-01

    The entry of pharmaceuticals into the water cycle from sewage treatment plants is of growing concern because environmental effects are evident at trace levels. Ozonation, UV- and UV/H(2)O(2)-treatment were tested as an additional step in waste water treatment because they have been proven to be effective in eliminating aqueous organic contaminants. The pharmaceuticals carbamazepine, ciprofloxacin, diclofenac, metoprolol and sulfamethoxazole as well as the personal care products galaxolide and tonalide were investigated in terms of degradation efficiency and by-product formation in consideration of toxic effects. The substances were largely removed from treatment plant effluent by ozonation, UV- and UV/H(2)O(2)-treatment. Transformation products were detected in all tested treatment processes. Accompanying analysis showed no genotoxic, cytotoxic or estrogenic potential for the investigated compounds after oxidative treatment of real waste waters. The results indicate that by-product formation from ozonation and advanced oxidation processes does not have any negative environmental impact. PMID:24225097

  13. Location and chemical bond of radionuclides in neutron-irradiated nuclear graphite

    International Nuclear Information System (INIS)

    The locations and the chemical forms (chemical bonds) of radionuclides in neutron-irradiated nuclear graphite have been determined in order to develop principal strategies for the management of graphitic nuclear waste. Due to the relatively low concentration of radionuclides in neutron-irradiated nuclear graphite (<1 ppm) direct spectroscopic methods are not applicable to investigate chemical structures. Therefore, methods by analogy have been applied. Such methods are investigations of the chemically detectable precursors of radionuclides in neutron-irradiated nuclear graphite and subjection of irradiated graphite to different chemical reactions followed by measurements of the radionuclide-containing reaction products by sensitive radiochemical methods. The paper discusses the applicability of these methods. The radionuclides investigated in this study can be divided into three parts: tritium, radiocarbon and metallic activation and fission products. Tritium can be bound in neutron-irradiated nuclear graphite as strongly adsorbed tritiated water (HTO), in oxygen-containing functional groups (e.g. C–OT) and as hydrocarbons (C–T). Radiocarbon is covalently bound with the graphite structure. The activity can be described by a homogeneously distributed part and a heterogeneously distributed part (enriched on surfaces or in hotspots). Metallic radionuclides can be bound as ions or covalent metal–carbon compounds. The distribution of all these radionuclides is mainly dependent on the distribution of their inactive precursors

  14. Secondary organic aerosol (trans)formation through aqueous phase guaiacol photonitration: chemical characterization of the products

    Science.gov (United States)

    Grgić, Irena; Kitanovski, Zoran; Kroflič, Ana; Čusak, Alen

    2014-05-01

    One of the largest primary sources of organic aerosol in the atmosphere is biomass burning (BB) (Laskin et al. 2009); in Europe its contribution to annual mean of PM10 is between 3 and 14 % (Maenhaut et al. 2012). During the process of wood burning many different products are formed via thermal degradation of wood lignin. Hardwood burning produces mainly syringol (2,6-dimetoxyphenol) derivatives, while softwood burning exclusively guaiacol (2-methoxyphenol) and its derivatives. Taking into account physical properties of methoxyphenols only, their concentrations in atmospheric waters might be underestimated. So, their aqueous phase reactions can be an additional source of SOA, especially in regions under significant influence of wood combustion. An important class of compounds formed during physical and chemical aging of the primary BBA in the atmosphere is nitrocatechols, known as strong absorbers of UV and Vis light (Claeys et al. 2012). Very recently, methyl-nitrocatechols were proposed as suitable markers for highly oxidized secondary BBA (Iinuma et al. 2010, Kitanovski et al. 2012). In the present work, the formation of SOA through aqueous phase photooxidation and nitration of guaiacol was examined. The key objective was to chemically characterize the main low-volatility products and further to check their possible presence in the urban atmospheric aerosols. The aqueous phase reactions were performed in a thermostated reactor under simulated sunlight in the presence of H2O2 and nitrite. Guaiacol reaction products were first concentrated by solid-phase extraction (SPE) and then subjected to semi-preparative liquid chromatography.The main product compounds were fractionated and isolated as pure solids and their structure was further elucidated by using nuclear magnetic resonance spectroscopy (1H, 13C and 2D NMR) and direct infusion negative ion electro-spray ionization tandem mass spectrometry (( )ESI-MS/MS). The main photonitration products of guaiacol (4

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

    OpenAIRE

    A. Stenke; Hoyle, C. R.; Luo, B.; Rozanov, E.; J. Gröbner; L. Maag; Brönnimann, Stefan; 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 differ...

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

    OpenAIRE

    A. Stenke; Hoyle, C. R.; Luo, B.; Rozanov, E.; J. Gröbner; L. Maag; S. Brönnimann; 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...

  17. Radial size and chemical structure of nuclear tracks in polymers

    International Nuclear Information System (INIS)

    The radial size of track cores in CR-39 plastics for several types of ions has been determined by two different methods. First, atomic force microscope (AFM) observations were performed on the irradiated CR-39 subsequent to the slight chemical etchings. The track core radii for C, O, Ne and Xe ions evaluated from the intersections of the extrapolated lines, fitted to each growth curve of etch pit radius, were found to be in the range between 2.8 and 4.1 nm, independent of the ion species. Second, ultraviolet (UV)-visible spectra of the irradiated CR-39 were obtained at various fluences. Based on a track overlapping model, the track core radii are evaluated for Ne, Ar, Si and Fe ions. Their core radii were almost proportional to the cube root of the stopping power. The results from the two different measurements are in good agreement with each other. (author)

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

    International Nuclear Information System (INIS)

    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 (U3Si2). 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, UF4; uranium oxide, UO2 and U3O8; 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)

  19. Plasma-Chemical Synthesis of Oxide Powders Using Transformer-Coupled Discharge

    International Nuclear Information System (INIS)

    An experimental investigation of transformer-coupled discharge in an Ar-O2 mixture with the addition of SiCl4, TiCl4 and ZrCl4 has been carried out under the atmospheric pressure of plasma-forming gases. Discharge power and discharge heat losses have been determined, and the dispersion and phase composition of reaction products (oxide powders) has been analyzed with SEM and X-ray diffraction analysis. Investigations reveal the formation of ultrafine oxide powders in the case of vaporized chloride (SiCl4 and TiCl4) injecting into the transformer coupled discharge. In the case of fine powder (ZrCl4) injection, full oxidation was not observed and reaction products consisted of a mixture of ZrO2 and ZrOCl2. A conclusion has been made regarding the perspectives of using transformer-coupled discharge to produce ultrafine oxide powders. (plasma technology)

  20. Experimental and theoretical analysis of vacuum circuit breaker prestrike effect on a transformer

    OpenAIRE

    Popov, M.; Smeets, RPP René; Sluis, van der, B.J.; Herdt, de, H; Declercq, J.

    2009-01-01

    The work presented in this paper deals with the investigation of circuit breaker prestrike effect that occurs during energizing a distribution transformer. An experimental test setup that consists of a supply transformer, a vacuum circuit breaker (VCB), a cable and a test transformer is built, and the prestrikes in the VCB are recorded. The test transformer is a prototype distribution transformer, with installed measuring points along transformer windings in each phase. Voltage oscillations a...

  1. 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.

  2. Mo- and V-catalyzed transformation of biomass into high-value chemicals

    DEFF Research Database (Denmark)

    Nielsen, Lasse Bo; Dethlefsen, Johannes Rytter; Lupp, Daniel;

    2014-01-01

    The possibility of converting biomass into higher-value chemicals has received increased attention over the last few years. If biomass could be converted into biofules or platform chemicals, then it could constitute a large source of renewable energy and economy for society....

  3. Cost effectiveness of dilute chemical decontamination

    International Nuclear Information System (INIS)

    The basic principles of dilute chemical decontamination are described, as well as the method of application. Methods of computing savings in radiation dose and costs are presented, with results from actual experience and illustrative examples. It is concluded that dilute chemical decontamination is beneficial in many cases. It reduces radiation exposure of workers, saves money, and simplifies maintenance work

  4. Efficiency factor of a chemical nuclear reactor with gamma sources

    International Nuclear Information System (INIS)

    A chemonuclear reactor is simulated in order to calculate the efficiency factor of molecular species in chemical reactions induced by gamma radiation, with the purpose to obtain information for its design and consider the electromagnetic energy as a possible solution to the present problem of energy. The research is based on a mathematical model of succesive Compton processes applied to spherical and cylindrical geometry and corroborated through the absorbed dose and the experimental date of the increase factor, for the radioisotopic sources Co-60 and Cs-137 relating the quantity of energy deposited into various cylinders with the G value, the relation radius/height of the reactor is optimized according to the molecular production. This is illustrated with the radiolysis of a solution of CH3OH/H2O which forms H2 and with the obtainment of C2H5Br that represents and industrial process induced radioactively. The results show a greater energy deposition with Cs-137 but a larger production of H2/hr with Co-60, and besides we can find high production values of C2H5Br. The cylinder with more advantages is that whose relation R/H is of 0.5. It can be concluded that the final selection of the reactor should be made after a more intense study of the used isotope and the source activity. The efficiency factor of H2 can be increased selecting the appropriate type and concentration of solute of the irradiated aqueous solutions

  5. The climatic effects of nuclear war

    Science.gov (United States)

    Turco, R. P.; Toon, O. B.; Ackerman, T. P.; Pollack, J. B.; Sagan, C.

    1984-01-01

    The effects of various US-USSR nuclear-exchange scenarios on global climate are investigated by means of computer simulations, summarizing the results of Turco et al. (1983) and follow-up studies using 3D global-circulation models. A nuclear-scenario model is used to determine the amounts of dust, smoke, radioactivity, and pyrotoxins generated by a particular type of nuclear exchange (such as a general 5,000-Mt exchange, a 1,000-Mt limited exchange, a 5,000-Mt hard-target counterforce attack, and a 100-Mt attack on cities only): a particle-microphysics model predicts the evolution of the dust and smoke particles; and a radiative-convective climate model estimates the effects of the dust and smoke clouds on the global radiation budget. The findings are presented in graphs, diagrams, and a table. Thick clouds blocking most sunlight over the Northern Hemisphere midlatitudes for weeks or months and producing ground-temperature reductions of 20-40 C, disruption of global circulation patterns, and rapid spread of clouds to the Southern Hemisphere are among the 'nuclear-winter' effects predicted for the 5,000-Mt baseline case. The catastrophic consequences for plant, animal, and human populations are considered, and the revision of superpower nuclear strategies is urged.

  6. 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. PMID:25442616

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

    International Nuclear Information System (INIS)

    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

  8. Microstructure of boron nitride coated on nuclear fuels by plasma enhanced chemical vapor deposition

    International Nuclear Information System (INIS)

    Three nuclear fuels, pure urania, 5% and 10% gadolinia containing fuels were coated with boron nitride to improve nuclear and physical properties. Coating was done by plasma enhanced chemical vapor deposition technique by using boron trichloride and ammonia. The specimens were examined under a scanning electron microscope. Boron nitride formed a grainy structure on all fuels. Gadolinia decreased the grain size of boron nitride. The fractal dimensions of fragmentation and of area-perimeter relation were determined. (orig.)

  9. Microstructure of boron nitride coated on nuclear fuels by plasma enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Durmazucar, H.H. [Cumhuriyet Univ., Sivas (Turkey). Kimya Muehendisligi Boeluemue; Guenduez, G. [Kimya Muehendisligi Boeluemue, Orta Dogu Teknik Ueniversitesi, Ankara 06531 (Turkey); Toker, C. [Elektrik-Elektronik Muehendisligi Boeluemue, Orta Dogu Teknik Ueniversitesi, Ankara 06531 (Turkey)

    1998-08-03

    Three nuclear fuels, pure urania, 5% and 10% gadolinia containing fuels were coated with boron nitride to improve nuclear and physical properties. Coating was done by plasma enhanced chemical vapor deposition technique by using boron trichloride and ammonia. The specimens were examined under a scanning electron microscope. Boron nitride formed a grainy structure on all fuels. Gadolinia decreased the grain size of boron nitride. The fractal dimensions of fragmentation and of area-perimeter relation were determined. (orig.) 19 refs.

  10. Productivity of a nuclear chemical reactor with gamma radioisotopic sources

    International Nuclear Information System (INIS)

    According to an established mathematical model of successive Compton interaction processes the made calculations for major distances are extended checking the acceptability of the spheric geometry model for the experimental data for radioisotopic sources of Co-60 and Cs-137. Parameters such as the increasing factor and the absorbed dose served as comparative base. calculations for the case of a punctual source succession inside a determined volume cylinder are made to obtain the total dose, the deposited energy by each photons energetic group and the total absorbed energy inside the reactor. Varying adequately the height/radius relation for different cylinders, the distinct energy depositions are compared in each one of them once a time standardized toward a standard value of energy emitted by the reactor volume. A relation between the quantity of deposited energy in each point of the reactor and the conversion values of chemical species is established. They are induced by electromagnetic radiation and that are reported as ''G'' in the scientific literature (number of molecules formed or disappeared by each 100 e.v. of energy). Once obtained the molecular performance inside the reactor for each type of geometry, it is optimized the height/radius relation according to the maximum production of molecules by unity of time. It is completed a bibliographical review of ''G'' values reported by different types of aqueous solutions with the purpose to determine the maximum performance of molecular hydrogen as a function of pH of the solution and of the used type of solute among other factors. Calculations for the ethyl bromide production as an example of one of the industrial processes which actually work using the gamma radiation as reactions inductor are realized. (Author)

  11. Analysis of phase W neutral connection burn-out on No. 1 main transformer in Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    No.1 main transformer in Daya Bay Nuclear Power Station experienced a burn-out failure of Phase W neutral connection. By analyzing the failure process, the condition of the protective system and the damages to the equipment, the root causes are summarized, the corrective measures put forward and successful results achieved

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

    International Nuclear Information System (INIS)

    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.

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

    International Nuclear Information System (INIS)

    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.)

  14. Effects of phosphate and silicate on the transformation

    NARCIS (Netherlands)

    Feng, Xionghan; Wang, X.; Zhu, M.; Koopal, L.K.; Xu, H.; Wang, Y.; Lui, F.

    2015-01-01

    Hydroxycarbonate green rust (GR1(CO32-)) was prepared by oxidation of aerated aqueous suspensions of Fe(II) hydroxide, and the presence of light promoted the transformation of GR1(CO32-) by dissolved O2 at pH 7.8 and 25 °C. Further transformation of GR1(CO32-) in the light was conducted in the prese

  15. Transformation of chemical constituents of lychee wine by simultaneous alcoholic and malolactic fermentations.

    Science.gov (United States)

    Chen, Dai; Liu, Shao-Quan

    2016-04-01

    This work examined for the first time the impact of malolactic fermentation (MLF) on the chemical constituents of lychee wine. Oenococcus oeni Viniflora Oenos (MLF inducer) and Saccharomyces cerevisiae MERIT.ferm were co-inoculated into lychee juice to induce simultaneous alcoholic fermentation (AF) and MLF. MLF did not affect sugar utilisation and ethanol production statistically (8.54% v/v for MLF and 9.27% v/v for AF). However, MLF resulted in dramatic degradation of malic and citric acids with concomitant increases of lactic acid, ethyl lactate and pH. The final concentrations of acetic and succinic acids between AF and MLF wines had no significant difference. The MLF wine contained significantly higher amounts of amino acids than the AF wine. More importantly, MLF significantly elevated the levels of potent aroma-active compounds including isoamyl acetate, linalool, geraniol and cis-rose oxide (to levels above or near respective detection thresholds), suggesting that MLF is an effective way of retaining the original lychee flavour. PMID:26593581

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

    International Nuclear Information System (INIS)

    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)

  17. Effective Methods of Nuclear Power Technology Transfer

    International Nuclear Information System (INIS)

    An effective technology transfer program is a necessary and significant step towards independence in nuclear power technology. Attaining success in the conduct of such a program is a result of a) the donor and recipient jointly understanding the fundamental concepts of the learning process, b) sharing a mutual philosophy involving a partnership relationship, c) joint and careful planning, d) rigorous adherence to proven project management techniques, and e) presence of adequate feedback to assure continuing success as the program proceeds. Several years ago, KEPCO President Park, Jung-KI presented a paper on technology in which he stated, 'Nuclear technology is an integration of many unit disciplines, and thus requires extensive investment and training in order to establish the base for efficient absorption of transferred technology.' This paper addresses President Park's observations by discussing the philosophy, approach, and mechanisms that are necessary to support an efficient and effective process of nuclear power technology transfer. All technical content and presentation methods discussed are based on a technology transfer program developed by Stone and Webster, as an Engineer/Constructor for nuclear power plants, and are designed and implemented to promote the primary program goal - the ability of the trainees and the organization to perform specific nuclear power related multi-discipline function independently and competitively

  18. Surface effects of underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Allen, B.M.; Drellack, S.L. Jr.; Townsend, M.J.

    1997-06-01

    The effects of nuclear explosions have been observed and studied since the first nuclear test (code named Trinity) on July 16, 1945. Since that first detonation, 1,053 nuclear tests have been conducted by the US, most of which were sited underground at the Nevada Test Site (NTS). The effects of underground nuclear explosions (UNEs) on their surroundings have long been the object of much interest and study, especially for containment, engineering, and treaty verification purposes. One aspect of these explosion-induced phenomena is the disruption or alteration of the near-surface environment, also known as surface effects. This report was prepared at the request of the Los Alamos National Laboratory (LANL), to bring together, correlate, and preserve information and techniques used in the recognition and documentation of surface effects of UNEs. This report has several main sections, including pertinent background information (Section 2.0), descriptions of the different types of surface effects (Section 3.0), discussion of their application and limitations (Section 4.0), an extensive bibliography and glossary (Section 6.0 and Appendix A), and procedures used to document geologic surface effects at the NTS (Appendix C). Because a majority of US surface-effects experience is from the NTS, an overview of pertinent NTS-specific information also is provided in Appendix B. It is not within the scope of this report to explore new relationships among test parameters, physiographic setting, and the types or degree of manifestation of surface effects, but rather to compile, summarize, and capture surface-effects observations and interpretations, as well as documentation procedures and the rationale behind them.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jun-hyung [Department of Nuclear and Energy System, Dongguk University, Gyeongju Campus, Gyeongju, 780-714 (Korea, Republic of)

    2013-07-01

    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)

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

    International Nuclear Information System (INIS)

    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. TETX: a novel nuclear selection marker for Chlamydomonas reinhardtii transformation

    OpenAIRE

    Garcia-Echauri, Sergio A; Cardineau, Guy A.

    2015-01-01

    Background Transformation of microalgae to obtain recombinant proteins, lipids or metabolites of economic value is of growing interest due to low costs associated with culture growth and scaling up. At present there are only three stable nuclear selection markers for the transformation of Chlamydomonas reinhardtii, which is the most commonly transformed microalgae, specifically: the aminoglycoside phosphotransferaseses aph7and aphVIII and the phleomycin resistance ble gene. As several microal...

  2. Chemical Decomposition of High-Level Nuclear Waste Storage/Disposal Glasses Under Irradiation

    International Nuclear Information System (INIS)

    The objective of this project is to employ the technique of electron spin resonance (ESR), in conjunction with other experimental methods, to study radiation-induced decomposition of vitreous compositions proposed for immobilization/disposal of high-level nuclear wastes (HLW) or excess weapons plutonium. ESR is capable of identifying, even at the parts-per-million level, displaced atoms, ruptured bonds, and free radicals created by radiation in such glassy forms. For example, one of the scientific goals is to search for ESR-detectable superoxide (O2 -) and ozonide (O3 -) ions, which could be precursors of radiation-induced oxygen gas bubbles reported by other investigators via the disproportionation reaction, 2O2 - : O2 2- + O2. The fundamental understandings obtained in this study will enable reliable predictions of the long-term effects of a and B decays of the immobilized radionuclides on the chemical integrity of HLW glasses

  3. Chemical Decomposition of High-Level Nuclear Waste Storage/Disposal Glasses Under Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Griscom, David L.

    1999-06-01

    The objective of this project is to employ the technique of electron spin resonance (ESR), in conjunction with other experimental methods, to study radiation-induced decomposition of vitreous compositions proposed for immobilization/disposal of high-level nuclear wastes (HLW) or excess weapons plutonium. ESR is capable of identifying, even at the parts-per-million level, displaced atoms, ruptured bonds, and free radicals created by radiation in such glassy forms. For example, one of the scientific goals is to search for ESR-detectable superoxide (O2 -) and ozonide (O3 -) ions, which could be precursors of radiation-induced oxygen gas bubbles reported by other investigators via the disproportionation reaction, 2O2 - : O2 2- + O2. The fundamental understandings obtained in this study will enable reliable predictions of the long-term effects of a and B decays of the immobilized radionuclides on the chemical integrity of HLW glasses.

  4. Thermo effect of chemical reaction in irreversible electrochemical systems

    International Nuclear Information System (INIS)

    From first law of thermodynamics the expressions of statistical calculation of 'Fundamental' and 'Thermo-chemical' thermal effects are obtained. Besides, method of calculation of thermal effect of chemical reactions in non-equilibrium electro-chemical systems is accurately discussed. (author). 7 refs

  5. Nuclear weapons, nuclear effects, nuclear war

    Energy Technology Data Exchange (ETDEWEB)

    Bing, G.F.

    1991-08-20

    This paper provides a brief and mostly non-technical description of the militarily important features of nuclear weapons, of the physical phenomena associated with individual explosions, and of the expected or possible results of the use of many weapons in a nuclear war. Most emphasis is on the effects of so-called ``strategic exchanges.``

  6. Determination of temperature and transverse flow velocity at chemical freeze-out in relativistic nuclear interactions

    International Nuclear Information System (INIS)

    We propose a parameter-free method to determine the temperature of a thermalized state in relativistic nuclear interactions, using the experimental μq/T and μs/T values, obtained from strange particle ratios. The hadron gas formalism and strangeness neutrality are employed to relate the quark-chemical potential μq and μs to the temperature and thus determine its value at chemical freeze-out. This temperature, together with the inverse slope parameter from mT distributions, enable the determination of the transverse flow velocity of the fireball matter, thus disentangling the thermal and flow effects. We study several nucleus-nucleus interactions from AGS and SPS and obtain the temperature, transverse flow velocity, and quark-chemical potentials. Extrapolating the systematics we predict the values of these quantities for ongoing and future experiments at AGS, SPS, and RHIC. We discuss the possibility of reaching the conditions for quark deconfinement and QGP formation and give distinct and identifiable signature. copyright 1996 The American Physical Society

  7. 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)

    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

  8. Degradation of chlorophenols and alkylphenol ethoxylates, two representative textile chemicals, in water by advanced oxidation processes: the state of the art on transformation products and toxicity.

    Science.gov (United States)

    Karci, Akin

    2014-03-01

    Advanced oxidation processes based on the generation of reactive species including hydroxyl radicals are viable options in eliminating a wide array of refractory organic contaminants in industrial effluents. The assessment of transformation products and toxicity should be, however, the critical point that would allow the overall efficiency of advanced oxidation processes to be better understood and evaluated since some transformation products could have an inhibitory effect on certain organisms. This article reviews the most recent studies on transformation products and toxicity for evaluating advanced oxidation processes in eliminating classes of compounds described as "textile chemicals" from aqueous matrices and poses questions in need of further investigation. The scope of this paper is limited to the scientific studies with two classes of textile chemicals, namely chlorophenols and alkylphenol ethoxylates, whose use in textile industry is a matter of debate due to health risks to humans and harm to the environment. The article also raises the critical question: What is the state of the art knowledge on relationships between transformation products and toxicity? PMID:24216260

  9. Considerations to the chemical reprocessing of nuclear fuel with thermodynamical methods

    International Nuclear Information System (INIS)

    On the basis of the state diagrams of the systems U-F-O-H, Pu-F-O-H, Zr-F-O-H, Nb-F-O-H new ways are shown to unit dry processes of the chemical fuel reprocessing with the proved Purex-Process. Conclusions are drawn for the conversion of nuclear fuel. (author)

  10. Physical and chemical characteristics of lead-iron phosphate nuclear waste glasses

    International Nuclear Information System (INIS)

    Experimental determinations of the properties of lead-iron phosphate glasses pertinent to their application to the problem of permanently disposing of high-level nuclear wastes have been carried out. These investigations included studies of the composition and physical properties of nuclear waste glasses (NWG), as well as the effect of preparation conditions. Lead-iron phosphate nuclear waste glasses were prepared by dissolving simulated US defense wastes or simulated commercial power reactor wastes in molten lead-iron phosphate melts at temperatures between 900 and 10500C. The measured physical and chemical properties of the nuclear waste glasses formed by cooling these melts and annealing included the following: (1) aqueous corrosion resistance as a function of the solution pH, solution temperature, and glass composition, (2) glass density, (3) thermal expansion coefficient, (4) glass transition temperature and softening point, (5) heat capacity, (6) critical cooling rate, (7) temperature for the maximum crystallization rate, (8) relative solubility of waste oxides in the glass melt, (9) reactions between the molten glass and the melting crucible (Pt, ZrO2, Al2O3), and (10 studies of possible metal cannister materials. Experimental results for the lead-iron phosphate NWG are compared to available data for borosilicate NWG. Relative to borosilicate NWG, the lead-iron phosphate glasses have several distinct advantages which include a much lower aqueous corrosion rate, a lower preparation temperature, and the ability to immobilize many types of commercial and defense-related high-level radioactive wastes. 34 refs., 18 figs., 10 tabs

  11. Chemical and biological investigations of a transformer accident at Binghamton, NY

    OpenAIRE

    O'Keefe, Patrick W.; Silkworth, Jay B.; Gierthy, John F.; Smith, Robert M.; DeCaprio, Anthony P; Turner, James N.; Eadon, George; Hilker, David R.; Aldous, Kenneth M.; Kaminsky, Laurence S; Collins, Doris N.

    1985-01-01

    A transformer fire occurred in a state office building in Binghamton, NY on February 5, 1981. Particulates from inside surfaces of ceiling panels on 16 of the 17 floors had concentrations of polychlorinated dibenzofurans (PCDFs) ranging from < 1 part per million (ppm) to 1200 ppm while polychlorinated biphenyl (PCB) concentrations varied from 28 ppm to 23,000 ppm. In spite of the wide variations in contaminant concentrations, complete analytical data from 11 floors showed that there was a con...

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

    International Nuclear Information System (INIS)

    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)

  13. Increased expression of transforming growth factor-β and receptors in primary human airway fibroblasts from chemical inhalation patients.

    Directory of Open Access Journals (Sweden)

    Monireh Sadat Mirzamani

    2013-06-01

    Full Text Available The widespread use of sulfur mustard  (SM as a chemical warfare agent in the  past century has proved its long-lasting toxic effects. Despite a lot of research over the past decades on Iranian veterans, there are still major gaps in the SM literature. Transforming growth  factor  (TGF-β,  a  cytokine  that  affects  many  different  cell processes,  has  an important role in the lungs of patients with some of chronic airway diseases, especially with respect to airway remodeling in mustard lung.Primary airway fibroblasts from epibronchial biopsies were cultured, and gene expression of TGF-β1, TGF-β2, TbR-I and TbR-II in fibroblasts of SM injured patients and controls were investigated. Expression of TGF-βs and receptors was measured by RT-PCR. Protein level of TGF-β1was surveyed by western blot.Our  findings revealed that expression levels of TGF-β1,  TGF-β2,  TbR-I and TbR-II were upregulated in the  airway fibroblasts of  SM exposed patients  in comparison  with control samples. TGF-β1 expression was shown to be markedly increased in primary lung fibroblasts of chemically injured patients.Our  novel data, suggested that  over-expression of TGF-β  molecule and receptors  in primary airway fibroblasts of mustard gas injured patients may be involved in progression of airway remodeling of these patients.

  14. Leading Teams in an International Project Context : The Effectiveness of Transformational and Transactional Leadership

    OpenAIRE

    2011-01-01

    Several scholars have argued that the effects of transformational leadership vary according to the context in which it is executed. In this study, we examined the effectiveness of transformational and transactional leadership on job satisfaction and team performance, and the effectiveness of transformational and transactional leader behaviors in different levels of environmental dynamism. We also tested tolerance for ambiguity as a moderator on the relationship between transformational leader...

  15. KAERI's technology development program of chemical decontamination for nuclear power reactors

    International Nuclear Information System (INIS)

    The activated corrosion products formed on the internal surface of primary coolant system of nuclear power plants can be removed by chemical decontamination. Dilute chemical decontamination method is widely used in consideration of keeping base metal integrity and producing relatively small amount of resulting radwastes. The application of chemical decontamination to PWRs is limited at present mainly to the channel heads of steam generators, but a growing necessity of entire NSSS decontamination is expected to accelerate the development and demonstration of the technology so that the commercial application of the technology will be realized in early 1990s. In Korea, nine nuclear power plants of PWR type except one will be available by 1989. The first chemical decontamination of the steam generator channel head of this nuclear power plant was done in 1984 by a foreign technology. KAERI's chemical decontamination technology development program funded by the Ministry of Science and Technology was started in 1983 to establish the technical guidelines and criteria and to obtain the technical self reliance. It is described. (Kako, I.)

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

    Science.gov (United States)

    Basa, Adina; Thaulow, Christian; Barnoush, Afrooz

    2013-11-01

    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.

  17. Chemical Composition and Antibacterial Effects of

    Directory of Open Access Journals (Sweden)

    SS Saei Dehkordi

    2009-10-01

    Full Text Available Introduction & Objective: Rosmarinus officinalis L. as a member of the Lamiaceae family and lysozyme as a natural antibacterial agent is important in food microbiology, because of its characteristics. The aim of the present study was to determine the chemical composition and anti-listerial activity of Rosmarinus officinalis essential oil (REO alone and in combination with lysozyme for enhancement of anti-listerial activity of both substances. Materials & Methods: Rosmarinus officinalis L. was purchased from a local grocery store at Shahrekord and was identified by the Institute of Medicinal Plants, ACECR. The air-dried aerial parts were subjected to hydrodistillation using a Clevenger apparatus to obtain essential oil and yielded oil was analyzed by GC/MS. Antibacterial activity (on basis of Minimum Inhibitory Concentration (MIC of REO was studied separately and in combination with unheated lysozyme (L and heat-treated lysozyme (HTL on Listeria monocytogenes at different pH (5, 6 and 7 by a micro-broth dilution assay. The collected data were analyzed by SPSS software. Results: In the current study, 98.05% of constituents of the essential oil were identified. The major components were α-pinene (14.06%, 1,8-cineole (13.62%, verbenone (11.2%, camphor (10.51%, borneol (7.3%, 3-octanone (7.02%, camphene (5.46% and linalool (5.07%. The inhibitory action of REO was stronger at lower pH especially 5 (MIC=225 μg/mL. Inhibition by L at pH 5 was 640 μg/mL but no inhibition was seen at pH 7. HTL resulted in more effective inhibition than L, especially at pH 5 and heat-treatment 80˚C (MIC: 160 μg/mL. Conclusion: Combination of L + REO and particularly HTL + REO was led to enhancement of bacterial inhibition. It was concluded that REO by the identified chemical composition was effective alone or in combination with L or HTL on Listeria monocytogenes as a food-borne pathogen.

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

    International Nuclear Information System (INIS)

    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)

  19. Climatic Effects of Regional Nuclear War

    Science.gov (United States)

    Oman, Luke D.

    2011-01-01

    We use a modern climate model and new estimates of smoke generated by fires in contemporary cities to calculate the response of the climate system to a regional nuclear war between emerging third world nuclear powers using 100 Hiroshima-size bombs (less than 0.03% of the explosive yield of the current global nuclear arsenal) on cities in the subtropics. We find significant cooling and reductions of precipitation lasting years, which would impact the global food supply. The climate changes are large and longlasting because the fuel loadings in modern cities are quite high and the subtropical solar insolation heats the resulting smoke cloud and lofts it into the high stratosphere, where removal mechanisms are slow. While the climate changes are less dramatic than found in previous "nuclear winter" simulations of a massive nuclear exchange between the superpowers, because less smoke is emitted, the changes seem to be more persistent because of improvements in representing aerosol processes and microphysical/dynamical interactions, including radiative heating effects, in newer global climate system models. The assumptions and calculations that go into these conclusions will be described.

  20. Adolescents' Knowledge of Nuclear Issues and the Effects of Nuclear War.

    Science.gov (United States)

    Roscoe, Bruce; Goodwin, Megan P.

    1987-01-01

    Surveyed 357 college students to assess awareness of the status of nuclear arms development and possible effects of nuclear war on people and environment. Results suggest that older adolescents are extremely uninformed regarding the current status of nuclear issues and consequences of nuclear war. Indicates a strong need to educate young people…

  1. Amplification of SV40 and cellular genes in SV40 transformed Chinese hamster embryo cells treated with chemical carcinogens

    International Nuclear Information System (INIS)

    To study the effect of chemical carcinogens on the amplification of specific genes, we have constructed a model system, utilizing integrated SV40 as an example for an endogenous gene. Recently, we have shown that exposure of SV40 transformed Chinese hamster cells to a variety of carcinogens induced the amplification of the integrated SV40 genome. Functional T-antigen was necessary for the amplification phenomenon. The work presented in this manuscript shows that the functional origin of replication, which consists of the sequences at the origin of replication and an active T-antigen, is required for the amplification. Utilizing cloned SV40 inserts and the adjacent Chinese hamster sequences we were able to show that SV40 and the flanking cellular sequences were amplified. As the distance from the SV40 origin of replication increased, the extent of amplification was decreased. The amplified sequences are associated with both chromosomal and extrachromosomal sequences. Carcinogen-mediated amplification is not restricted to SV40 sequences and endogenous genes such as dehydrofolate reductase (dhfr), the histocompatibility gene (HLA) and c-ras/sup Ha/ gene are amplified. 26 references, 5 figures

  2. 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.

  3. Transformational activity by top management for the enhancement of safety in a nuclear power plant in Japan

    International Nuclear Information System (INIS)

    Using Engestroem's activity theory, we investigated how company-wide transformational activity was initiated and how it has changed everyday activities in a nuclear power plant in Japan. We renamed 'learning activity' in the theory 'transformational activity' in this paper. It was defined as an activity that continues for a certain amount of period and transforms existing everyday organizational activities into new ones by changing the underlying premises of activities. We described a precise example of transformational activity we observed in our intensive field work in a large electric power company where the first fatal accident in the history of a nuclear power plant in Japan occurred in one plant several years ago. Using the model of activity theory, this transformational activity was depicted as following: the reform committee for maintenance work (subject of activity) acted on existing everyday activities for maintenance (object of activity) and transformed them into new ones (outcome of activity) with the use of requests submitted by subcontracted workers for improvement of working conditions and a budget to materialize them (mediating artifact of activity), in the collaboration with the top management who launched and persistently supported the reform committee, subcontracted workers responsible for the physical labor force in operational fields who actively submitted requests for improvement, and workers of the electric company who reviewed the requests and materialized most of them by a budgetary step (community member of activity and division of labor of activity), and with the shared awareness that any measures should be taken to actualize the lesson from the accident (rule of activity). Prior to the accident, safety was regarded as important as long as efficiency would not be sacrificed. Now, in the everyday activities achieved by the transformational activity, safety in operational fields is emphasized to the extent that anyone could not have

  4. 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

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

    International Nuclear Information System (INIS)

    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. QED theory of the nuclear recoil effect in atoms

    CERN Document Server

    Shabaev, V M

    1998-01-01

    The quantum electrodynamic theory of the nuclear recoil effect in atoms to all orders in \\alpha Z is formulated. The nuclear recoil corrections for atoms with one and two electrons over closed shells are considered in detail. The problem of the composite nuclear structure in the theory of the nuclear recoil effect is discussed.

  7. QED theory of the nuclear recoil effect in atoms

    OpenAIRE

    Shabaev, V. M.

    1997-01-01

    The quantum electrodynamic theory of the nuclear recoil effect in atoms to all orders in \\alpha Z is formulated. The nuclear recoil corrections for atoms with one and two electrons over closed shells are considered in detail. The problem of the composite nuclear structure in the theory of the nuclear recoil effect is discussed.

  8. Effectiveness of Land Use Structure Evolution to Industrial Structure Transformation

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Scarcity of land resources and transformation of industrial structure is a pair of contradictory elements.We derive the characteristics of land use structure and industrial structure transformation in Xining City using Transformation Coefficient(TC):first,in the period 1999-2000,the land use structure coefficient(θ1) declined by 79.55%,but the overall evolution trend is gentle;second,the transformation coefficient of industrial structure(θ2) tended to decline ceaselessly on the whole,a decrease of 36.09%(overall,the transformation coefficient of industrial structure is slightly greater than the land use structure coefficient);third,the inter-annual variation of the two experienced ups and downs(in the period 1999-2007,the inter-annual variation was great and in the period 2008-2010,the inter-annual variation tended to be gentle).On the basis of autocorrelation and co-integration model,we draw the following conclusions through analysis:first,the land use structure in Xining City plays a role in promoting industrial structure transformation;second,there is a long-term equilibrium relationship between the two.Finally,relevant policy recommendations are put forward for the industrial development in Xining City.

  9. Modeling mechanical effects on promotion and retardation of martensitic transformation

    Energy Technology Data Exchange (ETDEWEB)

    Maalekian, Mehran, E-mail: mehran.maalekian@ubc.ca [Department of Materials Engineering, University of British Columbia, 309-6350 Stores Road, Vancouver, B.C. V61Z4 (Canada); Kozeschnik, Ernst [Christian Doppler Laboratory for ' Early Stages of Precipitation' , Institute of Materials Science and Technology, Vienna University of Technology (Austria)

    2011-01-25

    Research highlights: {yields} Compressive elastic stresses up to 250 MPa are applied in continuous cooling. {yields} Using the thermodynamic data and maximum value of the mechanical driving force the predicted increase in M{sub s} ({approx}0.1 K/MPa) is in agreement with experiment {yields} Austenite was deformed plastically at different temperatures (800 deg. C-1100 deg. C). {yields} High deformation temperature (i.e. 1100 deg. C) as well as low plastic strain (i.e. {epsilon}{sub ave} {approx} 30%) do not affect martensite transformation noticeably, whereas lower deformation temperature (e.g. 900 deg. C) and large plastic strain (i.e. {epsilon}{sub ave} {approx} 70%) retards martensite transformation. {yields} The theory of mechanical stabilization predicts the depression of M{sub s}. - Abstract: The influence of compressive stress and prior plastic deformation of austenite on the martensite transformation in a eutectoid steel is studied both experimentally and theoretically. It is demonstrated that martensite formation is assisted by stress but it is retarded when transformation occurs from deformed austenite. With the quantitative modeling of the problem based on the theory of displacive shear transformation, the explanation of the two opposite roles of mechanical treatment prior to or simultaneously to martensite transformation is presented.

  10. Comparison of maintenance scheme effects on power transformer reliability performance

    OpenAIRE

    I. C. Durán; L. S. Rosero; A. Pavas; O. G. Duarte

    2015-01-01

    Power transformer failures have a significant impact on electrical systems reliability, as they compromise the electricity delivery. Failures impact the operational cost of electric utilities as they endanger the accomplishment of power commitments. Power transformer failure rate can be modeled from its health condition, which is determined from different condition parameters. This paper is aimed to compare different maintenance schemes that allow the asset to be available the longest possibl...

  11. Effects of scalp dermatitis on chemical property of hair keratin

    Science.gov (United States)

    Kim, Kyung Sook; Shin, Min Kyung; Park, Hun-Kuk

    2013-05-01

    The effects of scalp dermatitis (seborrheic dermatitis (SD), psoriasis, and atopic dermatitis (AD)) on chemical properties of hair keratin were investigated by Fourier transform infrared (FT-IR) spectroscopy. Hairs were collected from lesional regions affected by SD, psoriasis, and AD and non-lesional regions separately. The hairs with SD were taken from patients with ages of 16-80 years. The ages of patients with psoriasis ranged from 8 to 67 years, and all patients exhibited moderate disease. Hairs with AD were taken from the patients with ages of 24-45 years and the average SCORing atopic dermatitis (SCORAD) was 48.75. Hairs from 20 normal adults were collected as a control. The FT-IR absorbance bands were analyzed by the Gaussian model to obtain the center frequency, half width, height, and area of each band. The height and area of all bands in the spectra were normalized to the amide I centered at 1652 cm-1 to quantitatively analyze the chemical composition of keratin. The spectra of hair with scalp dermatitis were different with that of control, the amide A components centered at 3278 cm-1 were smaller than those of the control. The psoriasis hair showed a large difference in the IR absorbance band between lesional and non-lesional hairs indicating good agreement with the morphological changes. The hairs with diseases did not show differences in the content of cystine, which was centered at 1054 cm-1, from the control. The chemical properties of keratin were not significantly different between the hairs affected by SD, psoriasis, and AD. However, the changes induced by scalp dermatitis were different with weathering. Therefore, FT-IR analysis could be used to screen differences between the physiological and pathological conditions of scalp hair.

  12. Technique of chemical cleaning for removing corrosion products in nuclear reactor (PWR)

    International Nuclear Information System (INIS)

    The study of chemical cleaning technique for removing corrosion products in PWR type plant and power reactor have been carried in China Institute of Atomic Energy (CIAE), Beijing. The report summarizes the in results of screening test and qualification test of chemical cleaning technique, and the results of chemical cleaning to remove corrosion products (Fe304) in primary side of PWR type power reactor which chemical cleaning process has been carried by CIAE. The chemical cleaning agent (EDTA + assistant agent + inhibitor ) is effective for removing magnetite (Fe304 ≤ 17.5g/l).The process of chemical cleaning includes cleaning, rinse, passivation. The corrosion rate of materials is acceptable. The chemical cleaning technique is effective and safe for PWR type reactor. (author)

  13. Chemical modification of a polyacrylamide. Enhanced decontamination of soils and surfaces after a nuclear accident

    International Nuclear Information System (INIS)

    This contribution concerns the decontamination of soils and surfaces polluted by cesium and strontium after a nuclear accident. The decontamination rate by means of an industrial polyacrylamide previously selected for its mechanical covering properties is studied. The characteristics of the polymer and its cation-exchange capacity (CEC) are specified. The chemical modification of the polymer, involving a crosslinking path and functional grafting, affords an improvement of its decontaminating properties. (author). 6 refs., 4 figs., 1 tab

  14. Transformation of biogenic carbohydrates into levulinic acid and further hydrogenation using supported nanoparticle catalysts synthesized by chemical fluid deposition

    OpenAIRE

    Yan, Kai

    2011-01-01

    The primary objective of this thesis was to synthesize and identify powerful metal catalysts and key factors for the conversion of D-fructose and D-glucose to LA as well as the hydrogenation of LA to GVL. A general overview on the use of biomass for chemicals and potential biofuel production is provided. The catalytic transformation systems developed for the conversion of biomass-derived monomers to LA and GVL are reviewed. Meanwhile, an intensive overview of the preparation of supported nano...

  15. Study of effect of chromium on titanium dioxide phase transformation

    Indian Academy of Sciences (India)

    A Bellifa; L Pirault-Roy; C Kappenstein; A Choukchou-Braham

    2014-05-01

    MTi samples with different atomic chromium percentages were synthesized by sol–gel method and calcined at 400 °C under air. The effects of Cr and temperature on titanium dioxide phase transition were studied. In situ measurement showed the presence of anatase phase for all samples at temperature < 500 °C. Without Cr content, the anatase–rutile transition takes place at 600 °C and the rutile fraction increases with increase of temperature. In the presence of Cr content, rutile phase appeared at 700 °C. Cr2O3 phase was shown only in the case of CrTi20 content at 800 °C which indicates that the segregation remains modest. We have also studied the anatase–rutile transition kinetics by using in situ X-ray measurements. It was found that the anatase phase stability increases as the chromium content increases. Results confirm that the transformation of anatase–rutile is of first order.

  16. Ab Initio Calculations of Deuterium Isotope Effects on Chemical Shifts of Salt-Bridged Lysines

    DEFF Research Database (Denmark)

    Ullah, Saif; Ishimoto, Takayoshi; Williamson, Mike P.;

    2011-01-01

    Deuterium isotope effects measure the change in chemical shift on substitution of a proton by deuterium. They have been calculated by direct treatment of the H/D nuclear quantum effect using a multicomponent ab initio molecular orbital method based on a non-Born−Oppenheimer approximation. This me...

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

    International Nuclear Information System (INIS)

    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

  18. Transformation of Sorbitol to Biofuels by Heterogeneous Catalysis: Chemical and Industrial Considerations

    International Nuclear Information System (INIS)

    Decreasing oil supplies and increasing energy demand provide incentives to find alternative fuels. First, the valorisation of edible crops for ethanol and bio-diesel production led to first generation biofuels. Nowadays, research is focused on lignocellulosic biomass as a source of renewable carbon (second generation biofuels). Whereas the cellulosic ethanol production is in progress, a new way consisting of the transformation of ex-lignocellulose sugars and polyols towards light hydrocarbons by heterogeneous catalysis in aqueous phase has been recently described. This process is performed under mild conditions (T < 300 deg. C and P < 50 bar). It requires on one hand hydrogen formation by catalytic reforming of carbohydrates in aqueous phase and on the other hand, the dehydration/hydrogenation of polyols leading to alkanes by selective C-O bond cleavages. The challenge here is to conceive multifunctional catalytic systems that are stable, active and selective under the reaction conditions. The aim of this article is to present the involved reactions, the catalytic systems described in literature for that kind of transformation and examples of industrial applications. (authors)

  19. Physico-chemical interactions between radioactive effluents from a nuclear power station stack and plumes from a cooling tower: effects on ground deposition of radioactivity

    International Nuclear Information System (INIS)

    A broad outline of numerical modelling of the interaction between radioactive effluents and plumes from cooling towers will be given and some of the more important aspects dealt with in some detail. The discussion will include the influence of wind direction, the heights reached by the cooling tower plumes, their visible lengths, which in turn depend on prevailing atmospheric conditions (humidity and wind speed), and the influence of natural rain and artificial precipitation (due to vapour droplets from the cooling towers) on the rate of radioactive deposition (fallout and washout). The probable effects of this interaction on the annual radioactive deposition factors will be brought out with the help of results obtained by numerical modelling (the KUMULUS model) for certain atmospheric conditions. The results obtained will be compared with those presented by other authors

  20. Pathogenic effects of the human chemical biofield.

    Science.gov (United States)

    Rumyantsev, S N; Grzeszczuk, J

    1995-07-01

    Organisms release their antigens into the environment. Some antigens are volatile and may pass into the blood of other organisms during respiration. Fetal antigens enter the mother's bloodstream through the placenta. Foreign antigens in the blood can cause various chemical changes and may initiate an immune reaction. PMID:8524190

  1. Automated chemical monitoring in new projects of nuclear power plant units

    Science.gov (United States)

    Lobanok, O. I.; Fedoseev, M. V.

    2013-07-01

    The development of automated chemical monitoring systems in nuclear power plant units for the past 30 years is briefly described. The modern level of facilities used to support the operation of automated chemical monitoring systems in Russia and abroad is shown. Hardware solutions suggested by the All-Russia Institute for Nuclear Power Plant Operation (which is the General Designer of automated process control systems for power units used in the AES-2006 and VVER-TOI Projects) are presented, including the structure of additional equipment for monitoring water chemistry (taking the Novovoronezh 2 nuclear power plant as an example). It is shown that the solutions proposed with respect to receiving and processing of input measurement signals and subsequent construction of standard control loops are unified in nature. Simultaneous receipt of information from different sources for ensuring that water chemistry is monitored in sufficient scope and with required promptness is one of the problems that have been solved successfully. It is pointed out that improved quality of automated chemical monitoring can be supported by organizing full engineering follow-up of the automated chemical monitoring system's equipment throughout its entire service life.

  2. Inherently safe technologies-chemical and nuclear

    International Nuclear Information System (INIS)

    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

  3. The effects of nuclear war. 2. rev. enl. ed.

    International Nuclear Information System (INIS)

    Possible and probable effects of a nuclear war in Europe are described on the basis of a study by the Office of Technology Assessment, US Kongress ('The effects of nuclear war', Wash. D.C. 1979). (HP)

  4. Preface to the Issue: Transformations of Biomass and its Derivatives to Fuels and Chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Hongfei; Biddinger, Elizabeth J.; Mukarakate, Calvin; Nimlos, Mark; Liu, Haichao

    2016-07-01

    The research activities on biofuels and bio-products have been growing steadily regardless the volatility of the crude oil price in the past decade. The major driver is the imperative need of tackling the challenge of climate change. With the low carbon footprints, fuels and chemicals produced from renewable biomass resources, as the replacement of their petroleum counterparts, can contribute significantly on carbon emission reduction.

  5. 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.

  6. Initial Test of the Benchmark Chemical Approach for Predicting Microbial Transformation Rates in Aquatic Environments

    OpenAIRE

    Newton, Thomas D.; Gattie, David K.; Lewis, David L

    1990-01-01

    Using 2,4-dichlorophenoxyacetic acid methyl ester (2,4-DME) as a benchmark chemical, we determined relative pseudo-first-order rate coefficients for the butoxyethyl ester of 2,4-dichlorophenoxyacetic acid (2,4-DBE), methyl parathion, and methyl-3-chlorobenzoate in a diversity of microbial samples, including water, sediment, biofilm, and floating microbial mats collected from a laboratory mesocosm as well as from streams, lakes, and wetlands in Georgia and Florida. The decreasing order of reac...

  7. Chemical Composition and Antibacterial Effects of

    OpenAIRE

    SS Saei Dehkordi; H Tajik; Moradi, M; A Jafari Dehkordi; Ghasemi, S.

    2009-01-01

    Introduction & Objective: Rosmarinus officinalis L. as a member of the Lamiaceae family and lysozyme as a natural antibacterial agent is important in food microbiology, because of its characteristics. The aim of the present study was to determine the chemical composition and anti-listerial activity of Rosmarinus officinalis essential oil (REO) alone and in combination with lysozyme for enhancement of anti-listerial activity of both substances. Materials & Methods: Rosmarinus officinalis ...

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

    International Nuclear Information System (INIS)

    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

  9. Ion-radical intermediates of the radiation-chemical transformations of organic carbonates

    Science.gov (United States)

    Shiryaeva, Ekaterina S.; Sosulin, Ilya S.; Saenko, Elizaveta V.; Feldman, Vladimir I.

    2016-07-01

    The spectral features and reactions of ion-radical intermediates produced from organic carbonates in low-temperature matrices were investigated by EPR spectroscopy and quantum-chemical calculations. It was shown that radical cations of diethyl carbonate and dimethyl carbonate underwent intramolecular hydrogen transfer to yield alkyl-type species, as was suggested previously. Meanwhile, radical cation of EC demonstrates a ring cleavage even at 77 K, while radical cation of PC is probably intrinsically stable and undergo an ion-molecule reaction with a neighboring neutral molecule in dimers or associates. Radical anions were obtained in glassy matrices of diethyl ether or perdeuteroethanol. The radical anions of linear carbonates show photoinduced fragmentation to yield the corresponding alkyl radicals; such process may also occur directly under radiolysis. Radical anions of cyclic carbonates are relatively stable and yield only trace amounts of fragmentation products under similar conditions.

  10. Contributions concerning the effects of nuclear weapons

    International Nuclear Information System (INIS)

    The radiation fields resulting from the nuclear explosions at Hiroshima and Nagasaki have been re-assessed and re-evaluated, so that a new approach was possible for assessing the effects of neutrons on man, also of other than military neutron sources, but particularly the effects of neutron weapons on man and mammals. The other main topic of the contributions is protection of the population against neutron radiation environments by buildings such as shelters, or by ordinary basement rooms. There also is a glossary with terms and definitions. (DG)

  11. 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 ...

  12. Nuclear density empirical formula of the nucleus and the nuclear effect of the nucleon structure function

    International Nuclear Information System (INIS)

    The authors presented a nuclear density empirical formula of the nucleus, where authors have established the connection between the nuclear density and the mean binding energy in nucleus. By using the formula, authors can get the nuclear density for various nuclei with A≥12. By means of the nuclear density model, authors calculate the nuclear effect function RA1/A2 (x, Q2). The calculated results are in good agreement with EMC experimental data

  13. Immune effects of respiratory exposure to fragrance chemicals

    OpenAIRE

    Ezendam J; de Klerk A; Cassee FR; Fokkens PHB; van der Zee Park M; van Loveren H; Jong WH de; GBO

    2007-01-01

    Inhalation of the fragrance chemicals, isoeugenol and cinnamal, by mice resulted in immune reactions in the respiratory tract. This was observed in experiments performed by the RIVM (National Institute for Public Health and the Enviroment) of which results indicate that inhalation of some fragrance chemicals could induce unwanted effects on the immune system. Fragrance chemicals are common ingredients in such consumer products as cosmetics and scented products. Several fragrance chemicals are...

  14. Effect of the Fukushima nuclear disaster on global public acceptance of nuclear energy

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kwan Sik; Choi, Yoon Dong; Chun, Ki Jeong; Kim, Jin Kyu; Jung, Kyeong Chai; Lee, Yeong Keun; Park, Hyo Kook [Korea Atomic Energy Res. Inst., Taejon (Korea, Republic of)

    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).

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

    International Nuclear Information System (INIS)

    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)

  17. Effect of Deformation on Order-Disorder Phase Transformation in Cu-Zn Alloy

    Institute of Scientific and Technical Information of China (English)

    Zhang Ruijun; Xu Liang; Liu Jianhua

    2007-01-01

    The phase transformation temperature of ordered β' to disordered β in the Cu-Zn alloy was tested by DSC. The transformation activation energy was calculated and the effect of deformation of the phase transformation was discussed. The results show that the phase transformation temperature and activation energy of ordered β' to disordered β in the Cu-Zn alloy can be decreased going through deformation, and the phase transformation time can be also decreased. As a result, the order-disorder phase transformation occurs more easily.

  18. 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)

    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.

  19. Study relating to the physico-chemical behaviour of heavy water in nuclear reactors

    International Nuclear Information System (INIS)

    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)

  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. Solution conformations of the B-loop fragments of human transforming growth factor α and epidermal growth factor by 1H nuclear magnetic resonance and restrained molecular dynamics

    International Nuclear Information System (INIS)

    A restrained molecular dynamics simulation approach that explicitly includes the effect of the surrounding solvent molecules is applied to the NMR determination of the conformations of the B-loop fragments of human transforming growth factor α and epidermal growth factor. Backbone interproton distance restraints are obtained by using two-dimensional rotating frame nuclear Overhauser effect spectroscopy (ROESY). The simulations are carried out both in vacuum and in water. The results are discussed in terms of the energetics, agreement with the NMR distances, and the flexibility of the peptides

  2. Nuclear security in a transformed world

    International Nuclear Information System (INIS)

    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

  3. 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...

  4. The Effects of Integrated Transformational Leadership on Achievement

    Science.gov (United States)

    Boberg, John Eric; Bourgeois, Steven J.

    2016-01-01

    Purpose: Greater understanding about how variables mediate the relationship between leadership and achievement is essential to the success of reform efforts that hold leaders accountable for student learning. The purpose of this paper is to test a model of integrated transformational leadership including three important school mediators.…

  5. Some Properties of Multi-qubit Systems Under the Effect of Lorentz Transformations

    Science.gov (United States)

    Metwally, Nasser

    2015-09-01

    The Effect of Lorentz transformation on some properties of multi-qubit systems is investigated. It is shown that, the fidelity and entanglement decay as the Wigner's angles increase, but can be improved, if all the transformed particles are transformed with the same Wigner's angles. The upper bounds of the average capacity of the Greenberger-Horne-Zeilinger (GHZ) state increase while it decrease for W-state as the Wigner's angle of the observer decreases. Under Lorentz transformation, the tripartite states are transformed into another equivalent states and hence no change on the efficiency of these states to perform quantum information tasks.

  6. Effects of Nereis diversicolor on the transformation of 1-Methylpyrene and Pyrene

    DEFF Research Database (Denmark)

    Malmquist, Linus Mattias Valdemar; Christensen, Jan H.; Selck, Henriette

    2013-01-01

    -glucuronide as the most prominent metabolite. Transformation of 1-methylpyrene (21% transformed) was more than 3 times as efficient as pyrene transformation (5.6% transformed). Because crude oils contain larger amounts of C1−C4-substituted PAHs than nonsubstituted PAHs, the rapid and efficient transformation...... of sediment-associated 1-methylpyrene may result in a high exposure of water-living organisms to metabolites of alkyl-substituted PAHs, whose toxicities are unknown. This study demonstrates the need to consider fate and effects of substituted PAHs and their metabolites in risk assessments....

  7. Effect of re-austenitization on the transformation texture inheritance

    Science.gov (United States)

    Kaijalainen, A.; Suikkanen, P.; Porter, D. A.

    2015-04-01

    Bainitic-martensitic microstructures produced by direct quenching austenite subjected to different degrees of pancaking have been re-austenitized and quenched to fully martensitic structures in order to investigate the effect of prior texture on the final martensite texture. Three different prior austenite pancaking states varying from convex-like to highly pancaked were investigated using an ultrahigh-strength strip steel hot rolled with various finish rolling temperatures followed by direct quenching. Microstructures were characterized using FESEM and transformation texture analysed using FESEM-EBSD at the strip surface, quarter- thickness and mid-thickness positions. The results show that an increase in rolling reduction below the non-recrystallization temperature increases the intensities of ∼{554}α and ∼{112}α texture components in the ferrite along the strip mid-thickness and of the ∼{112}α component at the surface. The re-austenitization of the materials at 910°C for 30 min led to an inheritance of the same components from the parent specimens, but also increased the intensity of {001}α, {110}α and {011}α components.

  8. Regulation of chemical safety at fuel cycle facilities by the United States Nuclear Regulatory Commission

    International Nuclear Information System (INIS)

    When the U.S. Nuclear Regulatory Commission (NRC) was established in 1975, its regulations were based on radiation dose limits. Chemical hazards rarely influenced NRC regulations. After the Three Mile Island reactor accident in 1979, the NRC staff was directed to address emergency planning at non-reactor facilities. Several fuel cycle facilities were ordered to submit emergency plans consistent with reactor emergency plans because no other guidance was available. NRC published a notice that it was writing regulations to codify the requirements in the Orders and upgrade the emergency plans to address all hazards, including chemical hazards. The legal authority of NRC to regulate chemical safety was questioned. In 1986, an overfilled uranium hexafluoride cylinder ruptured and killed a worker. The NRC staff was directed to address emergency planning for hazardous chemicals in its regulations. The final rule included a requirement for fuel cycle facilities to certify compliance with legislation requiring local authorities to establish emergency plans for hazardous chemicals. As with emergency planning, NRC's authority to regulate chemical safety during routine operations was limited. NRC established memoranda of understanding (MOUs) with other regulatory agencies to encourage exchange of information between the agencies regarding occupational hazards. In 2000, NRC published new, performance-based, regulations for fuel cycle facilities. The new regulations required an integrated safety analysis (ISA) which used quantitative standards to assess chemical exposures. Some unique chemical exposure cases were addressed while implementing the new regulations. In addition, some gaps remain in the regulation of hazardous chemicals at fuel cycle facilities. The status of ongoing efforts to improve regulation of chemical safety at fuel cycle facilities is discussed. (authors)

  9. Chemical energy sources transformations by remote experiment

    OpenAIRE

    Tkáč, Lukáš; Schauer, František; Gerhátová, Žaneta

    2014-01-01

    The paper describes the first experience with the set up, functioning and data evaluation of the remote experiment "Energy transformation" accessible via Internet (http://remotelab10.truni.sk ) as a part of the e-laboratory at the Department of Physics, Faculty of Education, Trnava University in Trnava, Slovakia. The remote experiment control and data acquisition is based on the system ISES (Internet School Experimental System) and its control program and www page are built using the environm...

  10. Corrosion surveillance of the chemical decontamination process in Kuosheng nuclear power plant

    International Nuclear Information System (INIS)

    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)

  11. Pressure-induced phase and chemical transformations of lithium peroxide (Li2O2).

    Science.gov (United States)

    Dunuwille, Mihindra; Kim, Minseob; Yoo, Choong-Shik

    2016-08-28

    We present the pressure-induced phase/chemical changes of lithium peroxide (Li2O2) to 63 GPa using diamond anvil cells, confocal micro-Raman spectroscopy, and synchrotron x-ray diffraction. The Raman data show the emergence of the major vibrational peaks associated with O2 above 30 GPa, indicating the subsequent pressure-induced reversible chemical decomposition (disassociation) in dense Li2O2. The x-ray diffraction data of Li2O2, on the other hand, show no dramatic structural change but remain well within a P63/mmc structure to 63 GPa. Nevertheless, the Rietveld refinement indicates a subtle change in the structural order parameter z of the oxygen position O (13, 23, z) at around 35 GPa, which can be considered as a second-order, isostructural phase transition. The nearest oxygen-oxygen distance collapses from 1.56 Å at ambient condition to 1.48 Å at 63 GPa, resulting in a more ionic character of this layered crystal lattice, 3Li(+)+(LiO2)3 (3-). This structural change in turn advocates that Li2O2 decomposes to 2Li and O2, further augmented by the densification in specific molar volumes. PMID:27586935

  12. Chemical and physical considerations of the use of nuclear fuel spikants for deterrence

    Energy Technology Data Exchange (ETDEWEB)

    Selle, J. E.

    1978-10-01

    One proposed method of inhibiting the diversion of nuclear fuel for clandestine purposes is to add to the fuel a highly gamma-active material of such intensity that remote handling equipment is necessary in all stages of handling and reprocessing. This is called spiking for deterrence. The present work sought to identify candidate spikants and identify potential materials problems that might occur as the result of incorporation of these spikants with the fuel. Potential spikants were identified and thermodynamic analysis was performed to determine their chemical and physical states. Phase relationships between spikants (and their decay products) and the fuel constituents were surveyed. According to criteria defined in this report, /sup 60/Co, /sup 106/Ru, and /sup 144/Ce appear to have the greatest potential as spikants. Cerium should be present as the oxide, soluble in the fuel, while cobalt and ruthenium should be present in the metallic state with very low solubility in the fuel. Experimental work on the distribution of fission products and their interactions with cladding was also surveyed to provide information on the distribution of spikants in the fuel and describe the probable effects of spikants on the fuel. Cobalt, ruthenium, and cerium should not present any problems due to reaction with stainless steel cladding.

  13. 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.

  14. Characterization of solid phases and study of transformation kinetics in m-chlorofluorobenzene by 35Cl nuclear quadrupole resonance.

    Science.gov (United States)

    Pérez, Silvina; Wolfenson, Alberto

    2012-02-01

    Polymorphism is of widespread occurrence in the world of molecular crystals. In this work we present experimental results showing the existence of four solid phases in m-chlorofluorobenzene. A glass structure is achieved by quenching the liquid phase at 77 K. This glassy state crystallizes in a disordered phase at T~143 K, which in turn transforms to the high-temperature stable phase (phase I) at T~153 K. Depending on the thermal history of the sample, a different ordered phase (phase III) can be obtained. The disorder is attributed to a molecular orientational disorder. There is no evidence of molecular reorientation in any phase. A study of the disorder-order phase transformation kinetics, using nuclear quadrupole resonance, is presented. The results are analyzed following Cahn's theory. Nucleation seems to take place at grain boundaries. Growth rates for different temperatures have been determined. PMID:22209621

  15. Chemical leasing business models: a contribution to the effective risk management of chemical substances.

    Science.gov (United States)

    Ohl, Cornelia; Moser, Frank

    2007-08-01

    Chemicals indisputably contribute greatly to the well-being of modern societies. Apart from such benefits, however, chemicals often pose serious threats to human health and the environment when improperly handled. Therefore, the European Commission has proposed a regulatory framework for the Registration, Evaluation and Authorization of Chemicals (REACH) that requires companies using chemicals to gather pertinent information on the properties of these substances. In this article, we argue that the crucial aspect of this information management may be the honesty and accuracy of the transfer of relevant knowledge from the producer of a chemical to its user. This may be particularly true if the application of potentially hazardous chemicals is not part of the user's core competency. Against this background, we maintain that the traditional sales concept provides no incentives for transferring this knowledge. The reason is that increased user knowledge of a chemical's properties may raise the efficiency of its application. That is, excessive and unnecessary usage will be eliminated. This, in turn, would lower the amount of chemicals sold and in competitive markets directly decrease profits of the producer. Through the introduction of chemical leasing business models, we attempt to present a strategy to overcome the incentive structure of classical sales models, which is counterproductive for the transfer of knowledge. By introducing two models (a Model A that differs least and a Model B that differs most from traditional sales concepts), we demonstrate that chemical leasing business models are capable of accomplishing the goal of Registration, Evaluation and Authorization of Chemicals: to effectively manage the risk of chemicals by reducing the total quantity of chemicals used, either by a transfer of applicable knowledge from the lessor to the lessee (Model A) or by efficient application of the chemical by the lessor him/herself (Model B). PMID:17958507

  16. Chemical composition and structural transformations of amorphous chromium coatings electrodeposited from Cr(III) electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Safonova, Olga V. [Swiss-Norwegian Beamlines at European Synchrotron Radiation Facility, 38043 Grenoble Cedex (France); Vykhodtseva, Ludmila N. [Department of Electrochemistry, Faculty of Chemistry, Moscow State University, 119991 Moscow (Russian Federation); Polyakov, Nikolai A. [A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119991 Moscow (Russian Federation); Swarbrick, Janine C. [European Synchrotron Radiation Facility, 38043 Grenoble Cedex (France); Sikora, Marcin [European Synchrotron Radiation Facility, 38043 Grenoble Cedex (France); Department of Solid State Physics, Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Av. Mickiewicza 30, 30-059 Krakow (Poland); Glatzel, Pieter [European Synchrotron Radiation Facility, 38043 Grenoble Cedex (France); Safonov, Viktor A., E-mail: safon@elch.chem.msu.r [Department of Electrochemistry, Faculty of Chemistry, Moscow State University, 119991 Moscow (Russian Federation)

    2010-12-15

    Amorphous chromium coatings were electrodeposited from Cr(III)-based solutions containing organic (HCOONa) or phosphorus-containing (NaH{sub 2}PO{sub 2}) additives. Their structure was studied by a combination of X-ray diffraction (XRD), valence-to-core X-ray emission spectroscopy (XES) and X-ray absorption spectroscopy (XAS) at the Cr K-edge. Metalloid atoms (C or P) incorporated in electroplates structure are chemically bonded to chromium (i.e. are located in the first coordination shell). Upon annealing at elevated temperatures in vacuum, these amorphous coatings crystallize into a mixture of phases containing metallic chromium and chromium carbides or chromium phosphides. Quantitative analysis of valence-to-core XES data demonstrates that the average local structure of chromium in the amorphous coatings does not change significantly during crystallization.

  17. Toward understanding the effects of nuclear war

    International Nuclear Information System (INIS)

    The authors discuss the scientific justifications for studying the consequences of nuclear war. The consequences of nuclear war and nuclear winter - biotic impoverishment, climate change, pollution of the air, water, and soil - recapitulate in compressed time the patterns of ecological change humankind is even now imposing on the planet. By studying the biological consequences of nuclear war, important discoveries about the intricate nature of the global ecosystem may be made. Wiser management practices and more thorough appreciation of alterations in the physical and biological environment could results

  18. Political aspects of nuclear test effects at Semipalatinsk nuclear test site

    International Nuclear Information System (INIS)

    The paper describes tense struggle of Kazakhstan people for closure of the Semipalatinsk Nuclear Test Site. It reveals major foreign policy aspects and nuclear test effects for both Kazakhstan and the world community. (author)

  19. Chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solutions

    International Nuclear Information System (INIS)

    The standard covers analytical procedures to determine compliance of nuclear-grade uranyl nitrate solution to specifications. The following methods are described in detail: uranium by ferrous sulfate reduction-potassium dichromate titrimetry and by ignition gravimetry; specific gravity by pycnometry; free acid by oxalate complexation; thorium by the Arsenazo(III) (photometric) method; chromium by the diphenylcarbazide (photometric) method; molybdenum by the thiocyanate (photometric) method; halogens separation by steam distillation; fluorine by specific ion electrode; halogen distillate analysis: chloride, bromide and iodide by amperometric microtitrimetry; bromine by the fluorescein (photometric) method; sulfate sulfur by (photometric) turbidimetry; phosphorus by the molybdenum blue (photometric) method; silicon by the molybdenum blue (photometric) method; carbon by persulfate oxidation-acid titrimetry; nonvolatile impurities by spectrography; volatile impurities by rotating-disk spark spectrography; boron by emission spectrography; impurity elements by spark source mass spectrography; isotopic composition by multiple filament surface-ionization mass spectrometry; uranium-232 by alpha spectrometry; total alpha activity by direct alpha counting; fission product activity by beta and gamma counting; entrained organic matter by infrared spectrophotometry

  20. Effect of decontamination on nuclear power plant primary circuit materials

    International Nuclear Information System (INIS)

    The effect of repeated decontamination on the properties of structural materials of the WWER-440 primary coolant circuit was examined. Three kinds of specimens of 08Kh18Ni10T steel were used for radioactivity-free laboratory experiments; they included material obtained from assembly additions to the V-2 nuclear power plant primary piping, and a sheet of the CSN 17247 steel. Various chemical, electrochemical and semi-dry electrochemical decontamination procedures were tested. Chemical decontamination was based on the conventional AP(20/5)-CITROX(20/20) procedure and its variants; NP-CITROX type procedures with various compositions were also employed. Solutions based on oxalic acid were tested for the electrochemical and semi-dry electrochemical decontamination. The results of measurements of mass losses of the surfaces, of changes in the corrosion resistance and in the mechanical properties of the materials due to repeated decontamination are summarized. (Z.S.). 12 figs., 1 tab., 8 refs

  1. EFFECT OF THERMAL TREATMENT ON THE CHEMICAL COMPOSITION AND MECHANICAL PROPERTIES OF BIRCH AND ASPEN

    Directory of Open Access Journals (Sweden)

    Duygu Kocaefe

    2008-05-01

    Full Text Available The high temperature treatment of wood is one of the alternatives to chemical treatment. During this process, the wood is heated to higher temperatures than those of conventional drying. The wood structure changes due to decomposition of hemicelluloses, ramification of lignin, and crystallization of cellulose. The wood becomes less hygroscopic. These changes improve the dimensional stability of wood, increase its resistance to micro-organisms, darken its color, and modify its hardness. However, wood also might loose some of its elasticity. Consequently, the heat treatment conditions have to be optimized. Therefore, it is important to understand the transformation of the chemical structure of wood caused by the treatment. In this study, the modification of the surface composition of the wood was followed with Fourier transform infrared spectroscopy (FTIR and inverse gas chromatography (IGC under different experimental conditions. The effect of maximum treatment temperatures on the chemical composition of Canadian birch and aspen as well as the correlations between their chemical transformation and different mechanical properties are presented. FTIR analysis results showed that the heat treatment affected the chemical composition of birch more compared to that of aspen. The results of IGC tests illustrated that the surfaces of the aspen and birch became more basic with heat treatment. The mechanical properties were affected by degradation of hemicellulose, ramification of lignin and cellulose crystallization.

  2. Effects of solvent thermal treatment on the functional groups transformation and pyrolysis kinetics of Indonesian lignite

    International Nuclear Information System (INIS)

    Highlights: • Functional groups transformation were analyzed using FTIR and 13C NMR. • Relative percentage of functional group was semi-quantitatively calculated. • Oxygen-containing functional group was replaced by hydrogen or carbon-substituent. • Oxygen-loss was attributed to the loss of carbonyl, dihydric phenol and methoxyl. • Lower reactivity of pyrolysis was observed for the lignite upgrading at 300 °C. - Abstract: Organic solvent upgrading Indonesian lignite was performed in a 1 L autoclave under moderate temperature. The chemical structure and functional groups transformation of lignite upgraded by two organic solvents (ethanol and n-hexane) were analyzed to explore the upgrading mechanism of solvent thermal treatment by using Fourier transform infrared (FTIR) and 13C nuclear magnetic resonance (NMR). In addition, the characteristics of pyrolysis of treated samples were investigated using thermo gravimetric (TG) to clarify the variance of pyrolysis reactivity. Results showed that the carbon content and calorific value of upgraded lignite were significantly improved, and H/C and O/C ratios of treated samples were significantly reduced with the temperature increasing. The relative percentage of carbonyl and carboxyl carbon, oxygenated aliphatic carbon and methoxyl carbon of lignite upgraded at 300 °C decreased by 20–30%. However, the carbon-substituted and protonated aromatic carbon at 120–135 ppm and protonated aromatic carbon at 90–120 ppm were significantly increased after lignite was upgraded by the two solvents at above 200 °C. These transformations indicated that oxygen-containing functional group was substituted by hydrogen or carbon-substituent as temperature increased, and were intensified at above 200 °C. In addition, oxygen-loss in the treated samples was attributed to the loss of carbonyl group at 175 ppm, dihydric phenol at 147 ppm, and methoxyl group at 55 ppm. The activation energy of upgraded lignite at 300 °C were higher

  3. The effectiveness and development trend of nuclear third party liability insurance in the nuclear risk management

    International Nuclear Information System (INIS)

    Nuclear power considerably benefited mankind since it was utilized peaceably. The cleanness, safety and high efficiency of nuclear power were gradually known and recognized by the public. However at the same time, nuclear power had produced significant accident and consequently caused severe aftereffects during its utilization. Therefore, effective management of nuclear risk and reducing its accident probability are the social responsibilities of every nuclear nation. From the insurance point of view, this document analyzes the validity and development trends of nuclear third party insurance in nuclear risk management. It also introduces effectual experience in this field from nuclear insurance developed countries. This document discusses the necessity of consummating nuclear third party insurance under the aggressive development situation of nuclear power in our country. (author)

  4. Wavelets transforms and fuzzy logic in the eddy-current inspection of nuclear power plants steam generator tubes

    International Nuclear Information System (INIS)

    Nuclear power plants steam generators around the world have presented early damage history in their tubes, caused either by design errors or by inappropriate operation, which besides reducing the availability and the safety of the nuclear power plants it also generates heavy economical burden. To monitor the steam generators operational condition, the Eddy Current testing of their tubes is the non destructive method used to detect, localize, classify and to size the defects. The inspection is performed by inserting probes with coils in the tubes generating a signal correlated to the defect. These signals produced by the probe electric circuit are composed by the resistance and the inductive components which can be combined to produce a Lissajous figure in the complex plane. However, Eddy-Current signals contain noise which induce subjectivity inducing to errors in the inspector diagnosis. It is not uncommon to have different diagnosis from two inspectors about the same signal. The present work has the objective of supplying a methodology to analyze the signals which could help the inspector in the difficult task of interpreting the Eddy Current signals. It is proposed a method to remove the noise based on Wavelets Transforms. It is also proposed a normalization in the signal phase angle measurements. Furthermore, two additional characteristics are also studied, namely: the signal amplitudes and the widths of the Lissajous petals. The use of a Fuzzy Logic based inference engine is also developed and its use is demonstrated to be viable. The defects studied in this work are those which produces volumetric changes in the material. In order to test the proposed methodology, several artificial defects were produced in tubes using different types of materials like: brass, 316L stainless steel and Inconel 600 to produce a experimental data base. An Eddy-Current inspection equipment, the MIZ-17ET was used. Around 1000 time series signals of defects were acquired through

  5. Chemical transformations associated with neutronic irradiation of telluric acid; Transformations chimiques associees a l'irradiation neutronique de l'acide teliurique

    Energy Technology Data Exchange (ETDEWEB)

    Bertet, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-01-15

    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, {gamma} ) on Te{sup VI} and of the isomeric transitions {sup 131m}Te{sup VI} {yields} {sup 131}Te and {sup 129m}Te{sup VI} {yields} {sup 129}Te, and the oxidation states of {sup 131}I formed by {beta} decay of {sup 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 {sup 131}Te{sup VI} and {sup 129}Te{sup VI} formed by isomeric transition depends on the pH of the solution where this disintegration occurs. For instance, with {sup 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 {sup 131}I (reduced fraction (I{sup -}, IO{sup -}, I{sub 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{sub 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{sup VI} are formed in certain cases. (author) [French] Les transformations chimiques accompagnant l'irradiation neutronique de l'acide tellurique ont ete etudiees dans differentes conditions experimentales. On a examine notamment les consequences de la reaction (n, {gamma}) sur Te{sup VI

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

    International Nuclear Information System (INIS)

    The chemical and nuclear properties of Lr and Ha have been studied, using 3-minute 260Lr and 35-second 262Ha. The crystal ionic radius of Lr3+ 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, Am3+ through Es3+, obtained by x-ray diffraction methods, and to Md3+ and Fm3+ which were determined in the same manner as Lr3+. 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 Lr3+ and Md3+ is anomalously small, as the ionic radius of Lr3+ 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

  7. Substituent effects on nuclear shielding

    International Nuclear Information System (INIS)

    The important role of nuclear magnetic resonance (NMR) spectroscopy in chemistry arises largely from the consequences of nuclear shielding. The fact that nuclei in different electronic environments have different nuclear shieldings, and hence different chemical shifts, makes NMR a powerful probe of electronic structure. Empirical rules relating chemical shifts to substituent (σ) constants, electron densities, electronegativities, and a variety of other empirical parameters have proven of great benefit to problems of organic structural elucidation, and to fundamental studies of molecular electron distributions. This review focuses on one specific application in the latter category -the study of substituent electronic effects on chemical shifts. The aim is not to provide a compendium of substituent effects on chemical shifts to aid in structural assignments, but to show how fine detail relating to the distribution and polarization of electrons in molecules may be determined from chemical shift studies. Chapters are devoted to 1H, 11B, 13C, 15N, 17O, 19F, 31P, 33S, 77Se, 95Mo and 199Hg chemical shifts. (U.K.)

  8. The design, synthesis and fabrication of electrospun titanium dioxide nanomaterials for use in greener chemical transformations and photocatalysis

    Science.gov (United States)

    Obuya, Emilly Akinyi

    Electrospun TiO2 nanofibers present a unique class of active materials with optimized photoactivity and cost efficiency due to ease of synthesis and fabrication in bulk. The high aspect ratios for these nanostructured materials shorten the transportation length of electrons and holes from the crystal interface to the surface, thus accelerating their migration to the surface active sites. Additionally, the increased surface areas and high porosity ensures maximum adsorption of the reaction intermediates on the TiO2 surface, and high diffusion co-efficient within the material. The primary goal of this dissertation is to develop TiO2 nanofibers as an efficient and cost-effective catalyst for practical and multi-purpose application in greener chemical transformations and environmental remediation from organic pollutants in waste-waters. To achieve this, the surface, crystal and electronic structures of electrospun TiO2 will be optimized to allow for visible light-enhanced photodegradation processes. Pd nanoparticles of between 2-5 nm were successfully stabilized on the surface of electrospun nanofibers which had diameters between 150 ± 50 nm. The new catalyst was found to have increased surface area and improved catalytic functions compared to commercially available materials or other Pd-TiO2 catalysts produced by different modes of synthesis. The activity and selectivity of 0.05 mol% Pd-TiO2 catalyst in the Heck reaction has been investigated with a careful look into the nature of starting materials and products under varying conditions of temperature, solvent and base. The catalyst was found to be highly active under air atmosphere with reaction temperatures of up to 160°C. Optimized reaction conditions resulted in a 98% yield of trans-stilbene for the iodobenzene-styrene system with a TOF value of 7.85 min-1. The surface properties of TiO2 nanofibers were explored for the in-situ and ex-situ nucleation and growth of group VIII metal nanoparticles. The

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

    International Nuclear Information System (INIS)

    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)

  10. Two nuclear oncogenic proteins, P135gag-myb-ets and p61/63myc, cooperate to induce transformation of chicken neuroretina cells.

    OpenAIRE

    Amouyel, P; Laudet, V; P. Martin; Li, R P; Quatannens, B; Stéhelin, D; Saule, S.

    1989-01-01

    Several studies have shown that full transformation of primary rodent fibroblasts can be achieved in vitro through the cooperation of two oncogenes (usually one nuclear and one cytoplasmic) classified on the basis of different complementation groups. We have shown previously that cooperation between v-mil (cytoplasmic, serine-threonine kinase product), and v-myc (nuclear, DNA-binding product) is required to transform 7-day-old chicken neuroretina cells, which in usual culture medium do not ra...

  11. The effect of manganese on the kinetics of phase transformations of austenite in structural steels

    International Nuclear Information System (INIS)

    The aim of this work was to examine the effect of Mn on the kinetics of phase transformations of supercooled austenite. It was executed the 4 CCT diagrams for alloys of a variable Mn content. The obtained results indicate that with the increase of Mn concentrations in austenite in the range 0.73-2.94% the times to the beginning of its transformation are lengthened and the temperatures of these transformations into ferrite and the bainitic transformations are lengthened slightly whole only the time to the beginning of a pearlitic transformation is lengthened more strongly. In the range of 2.0-2.94% Mn the times to the beginnings of all transformations grow very strongly. (author)

  12. Prediction of Harmful Human Health Effects of Chemicals from Structure

    Science.gov (United States)

    Cronin, Mark T. D.

    There is a great need to assess the harmful effects of chemicals to which man is exposed. Various in silico techniques including chemical grouping and category formation, as well as the use of (Q)SARs can be applied to predict the toxicity of chemicals for a number of toxicological effects. This chapter provides an overview of the state of the art of the prediction of the harmful effects of chemicals to human health. A variety of existing data can be used to obtain information; many such data are formalized into freely available and commercial databases. (Q)SARs can be developed (as illustrated with reference to skin sensitization) for local and global data sets. In addition, chemical grouping techniques can be applied on "similar" chemicals to allow for read-across predictions. Many "expert systems" are now available that incorporate these approaches. With these in silico approaches available, the techniques to apply them successfully have become essential. Integration of different in silico approaches with each other, as well as with other alternative approaches, e.g., in vitro and -omics through the development of integrated testing strategies, will assist in the more efficient prediction of the harmful health effects of chemicals

  13. The Study of Magnetic Flux Shunts Effects on the Leakage Reactance of Transformers via FEM

    Directory of Open Access Journals (Sweden)

    Karim Abbaszadeh

    2010-09-01

    Full Text Available The influence of arrangement, dimensions, and magnetic permeability of the magnetic flux shunts on the flux distribution and leakage reactance of the power transformers is studied in this paper by using a finite elements method and a simple modeling approach. By using magneto-static analysis and finite element method, first the flux distribution in the 2D model of a core-type three phase power transformer and then using the magnetic stored energy method the leakage reactance of the transformer windings is calculated. By studying the different models including magnetic flux shunts, the effect of the arrangement, geometric dimensions as well as the magnetic permeability of the magnetic flux shunt on the leakage reactance of the transformer are studied and some interesting results are obtained. It is shown that the variation of these parameters in the transformer model has significant effects on the leakage reactance of the transformer.

  14. Physical and chemical properties and compositions of liquid effluents of a nuclear power reactor

    International Nuclear Information System (INIS)

    Behaviours of the released radioactive materials from a nuclear power plant to the marine environment depend largely on their physical and chemical properties. It is therefore important to grasp the compositions of the liquid effluents. From this point of view, some kinds of drainwater of a BWR plant were sampled. These samples are the laundry drain water at charcoal bed inlet and outlet, and the floor drain water. Suspended solids were separated from these samples physically with the step filtration method and ions chemically with the ion exchange resin. Radioactivity of Co-60, Mn-54 and Cs-137 was measured with γ spectrometer. Suspended solids of the laundry drain samples were also analysed with the instrumental methods (differential thermal analysis, x-ray diffraction analysis and x-ray fluorescence analysis)

  15. Developing superhydrophobic and oleophobic nanostructure by a facile chemical transformation of zirconium hydroxide surface

    Science.gov (United States)

    Sengupta, Arundhati; Malik, Satya Narayan; Bahadur, D.

    2016-02-01

    Stable hydro/oleo-phobic and superhydrophobic nanopowders, useful for self-cleaning applications, are synthesized at room temperature by modifying Zr(OH)4·nH2O with a very low surface-energy molecule-1H,1H,2H,2H-perfluorododecyltrichlorosilane whose long chain {sbnd (CH2)2(CF2)9CF3 moiety (PFD)} serves as surface-protrusion. The PFD-content is varied over 3.6-18.7 wt% in optimizing a hydrophilic to hydro/oleo-phobic or even to superhydrophobic transformation. Two halos in the X-ray diffraction pattern of amorphous Zr(OH)4·nH2O are accompanied by a peak at 2θ = 18.0° which grows in intensity progressively as the PFD-content increases from 5.2 to 18.7 wt%. The peak corresponds to sbnd CF2sbnd CF2sbnd crystalline order (10-20 nm) at the PFD-functionalized surface. The microstructure shows Zr(OH)4·nH2O as a cloud-like phase, bonded to plate-like sheaths (PFD moiety). The Csbnd F stretching bands at 1150 and 1210 cm-1 grow in intensity relative to that of Osbnd H stretching at 3460 cm-1 in proportion to the PFD-content. An 18.7 wt% PFD-functionalized sample exhibits a high contact angle CA = 153° for water (contact angle hysteresis = 4° and roll-off angle superhydrophobicity and oleophobicity. Surface-energy reduction due to PFD moiety together with an optimal spacing between the surface-protrusions explains the water/organic liquid repellency.

  16. Main transformer condition maintenance implementation in Qinshan nuclear power company

    International Nuclear Information System (INIS)

    QinShan Phase I Nuclear Power Limited Company is a 310 MW power generator station. With nearly twenty years' operation, station experienced in the equipment management areas and set up its own maintenance management program. In order to improve the management, station is searching for the optimization in the equipment maintenance. Especially the electrical transformer area, it is important and necessary of the condition maintenance implementation. In 2007, the period of the No. 10 station refueling overhaul maintenance, based on the operation condition of the main transformer and some deficiency in the equipment, it is implement the transformer condition maintenance. The transformer partly dismantled, changed some parts, modified some elements, monitored some performance parameters and evaluated the transformer condition. With these tasks implement, the deficiency of the transformer is cleared away, the performance of the transformer is improved and ensured the station safety operation in the next operation circulation. And it is also optimizing the station refueling overhaul management by the adjustment of the main electrical transformer maintenance time. And the implement accumulates abundance experience of the transformer condition maintenance and it also sets the implement example for the advanced management. (authors)

  17. Reactions of charged and neutral recoil particles following nuclear transformations. Progress report No. 10

    International Nuclear Information System (INIS)

    The status of the following programs is reported: study of the stereochemistry of halogen atom reactions produced via (n,γ) nuclear reactions with diastereomeric molecules in the condensed phase; decay-induced labelling of compounds of biochemical interest; and chemistry of positronium

  18. 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)

  19. 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)

    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

  20. 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

  1. Effects of Manure Fertilizer and Chemical Fertilizer on Nitrogen Transformation Bacteria and Soil Enzyme in Black Soil%农肥和化肥对黑土氮素转化功能菌和土壤酶的影响

    Institute of Scientific and Technical Information of China (English)

    于佳; 王宏燕; 赵伟; 宋立娟

    2011-01-01

    Various trends of soil function bacteria and its activity was Analyzed under different ratios of the manure and chemical fertilizers,in on the black soil field under maize. The results showed that the high manure fertilizer ratio scenario leads to an increase in ammonification bacteria and nitrobacteria, which were 2. 22 times and 4. 09 times of standard sample (CK) respectively. Meanwhile, the high chemical fertilizer ratio also contributed to a significant raise in the amount of denitrifying bacteria, which was 8.49 times of CK.Furthermore, Manure fertilizer scenario had a positive influence on soil microbial biomass carbon, nitrogen, soil urease and catalase as the analyzed data of activities of these factors were much higher than that of CK. Specifically speaking, the positive correlations existed in the following groups: soil microbial biomass C and soil urease activity, microbial biomass N and catalyse activity and microbial biomass and soil ammonification bacteria as well At the same time, soil microbial biomass C and soil ammonification bacteria had significant negative correlation ship.%实验以玉米田黑土为研究对象,主要研究土壤氮素转化功能菌及其活性在不同施入量农肥和化肥处理下的变化.结果表明:农肥高量处理使土壤氨化细菌和硝化细菌数量升高,分别是对照的2.22倍和4.09倍,而化肥高量处理使反硝化细菌数量明显增加,是对照的8.49倍;农肥处理对土壤微生物量碳、微生物量氮、土壤脲酶和土壤过氧化氢酶有促进作用,其活性明显高于对照.相关分析表明,土壤微生物量碳与土壤脲酶,土壤微生物量氮与过氧化氢酶和土壤氨化细菌之间均存在着极显著的正相关关系,而土壤微生物量碳与土壤氨化细菌之间存在着极显著的负相关关系.图8,表1,参14.

  2. Neoplastic transformation of human breast epithelial cells by estrogens and chemical carcinogens.

    Science.gov (United States)

    Russo, Jose; Tahin, Quivo; Lareef, M Hasan; Hu, Yun-Fu; Russo, Irma H

    2002-01-01

    Sporadic breast cancer, the most common cancer diagnosed in American and Northern European women, is gradually increasing in incidence in most Western countries. Prevention would be the most efficient way of eradicating this disease. This goal, however, cannot be accomplished until the specific agent(s) or mechanisms that initiate the neoplastic process are identified. Experimental studies have demonstrated that mammary cancer is a hormone-dependent multistep process that can be induced by a variety of compounds and mechanisms, that is, hormones, chemicals, radiation, and viruses, in addition to or in combination with genetic factors. Although estrogens have been shown to play a central role in breast cancer development, their carcinogenicity on human breast epithelial cells (HBECs) has not yet been clearly demonstrated. Breast cancer initiates in the undifferentiated lobules type 1, which are composed of three cell types: highly proliferating cells that are estrogen-receptor negative (ER-), nonproliferating cells that are ER positive (ER+), and very few (17p13.2. The relevance of these findings is highlighted by the observation that E(2)- and B[a]P-induced genomic alterations in the same loci found in ductal hyperplasia, ductal carcinoma in situ, and invasive ductal carcinoma of the breast. PMID:11921196

  3. Effects of stray DC currents on the performance of large core type transformers

    International Nuclear Information System (INIS)

    This paper presents the results of a study made on the effects of stray DC current on power transformer performance. A circuit model was developed to analyze the magnetic behavior of three-phase five-leg core type transformers. The magnetic field distribution was obtained for several different operating conditions by taking into account core geometry, core design, magnitude of D.C. current, and magnitude of A.C. voltage. The change in transformer performance is discussed

  4. The Effects of Solution Transformations to the System with Color Parameters

    Institute of Scientific and Technical Information of China (English)

    JU Guo-Xing; ZHAO Xian-Lin

    2001-01-01

    The effects of solution transformations to the six- and eight-vertex systems are discussed.Tthere are fourkinds of effects,the Hamiltonian of the system is invariant,its coupling coefficients change,some additional terms appear in the Hamiltonian,and the spin of the system is rotated by some angle about z axis under these transformations.In all the cases,the systems are still integrable if they are so before the transformation.

  5. Biological effects of radiation: The induction of malignant transformation and programmed cell death

    International Nuclear Information System (INIS)

    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, 95Zr, 103Ru, 106Ru, 141Ce, and 144Ce. 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

  6. The use of chemical gel for decontamination during decommissioning of nuclear facilities

    International Nuclear Information System (INIS)

    A technical research study was developed for testing the decontamination using chemical gels. The study was realized for different type of samples, systems often encountered in the VVR-S nuclear research reactor from Magurele–Romania. The results obtained in the study have demonstrated that the decontamination gels could be an efficient way to reduce or to eliminate the surface contamination of buildings or equipment’s, minimizing the potential for spreading contamination during decommissioning activities. - Highlights: • A research study was developed for testing the decontamination using chemical gels. • The purpose was realized by artificial contamination of eight types of materials. • Decontamination gels are an efficient way to reduce the surface contamination. • Minimize the potential for spreading contamination during decommissioning activities

  7. Effect of Multipoint Heterogeneity on Nonlinear Transformations for Geological Modeling: Porosity-Permeability Relations Revisited

    Institute of Scientific and Technical Information of China (English)

    J A Vargas-Guzmán

    2008-01-01

    An analysis of statistical expected values for transformations is performed in this study to quantify the effect of heterogeneity on spatial geological modeling and evaluations. Algebraic transformations are frequently applied to data from logging to allow for the modeling of geological properties. Transformations may be powers, products, and exponential operations which are commonly used in well-known relations (e.g., porosity-permeability transforms). The results of this study show that correct computations must account for residual transformation terms which arise due to lack of independence among heterogeneous geological properties. In the case of an exponential porosity-permeability transform, the values may be positive. This proves that a simple exponential model back-transformed from linear regression underestimates permeability. In the case of transformations involving two or more properties, residual terms may represent the contribution of heterogeneous components which occur when properties vary together, regardless of a pair-wise linear independence. A consequence of power- and product-transform models is that regression equationswithin those transformations need corrections via residual cumulants. A generalization of this result isthat transformations of multivariate spatial attributes require multiple-point random variable relations. This analysis provides practical solutions leading to a methodology for nonlinear modeling using correct back transformations in geology.

  8. 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.

  9. Effect of heat treatment on transformation behavior of Ti-Ni-V shape memory alloy

    International Nuclear Information System (INIS)

    Highlights: → New shape memory alloy (SMA) - Ti-50.8Ni-0.5V SMA. → The evolution laws of transformation types of annealed Ti-50.8Ni-0.5V SMA. → The evolution laws of transformation types of aged Ti-50.8Ni-0.5V SMA. → The effect laws of annealing on transformation temperature and hysteresis of the alloy. → The effect laws of aging on transformation temperature and hysterises of the alloy. - Abstract: Effects of annealing and aging processes on the transformation behaviors of Ti-50.8Ni-0.5V (atomic fraction, %) shape memory alloy were investigated by means of differential scanning calorimetry (DSC). The A → R/R → A (A - parent phase, R - R phase) type one-stage reversible transformation occurs in 350-400 deg. C annealed alloy, the A → R → M/M → R → A (M - martensite) type two-stage transformation occurs in 450-500 deg. C annealed alloy, the A → R → M/M → A type transformation occurs in 550 deg. C annealed alloy, and A → M/M → A type transformation occurs in the alloy annealed at above 600 deg. C upon cooling/heating. The transformation type of 300 deg. C aged alloy is A → R/R → A, and that of 500 deg. C aged alloy is A → R → M/M → A, while that of 400 deg. C aged alloy changes from A → R/R → A to A → R → M/M → R → A with increasing aging time. The effects of annealing and aging processes on R and M transformation temperatures and temperature hysteresis are given. The influence of annealing and aging temperature on transformation behaviors is stronger than that of annealing and aging time.

  10. Cleaning chemical and mechanical of heat exchangers in french nuclear plants; Limpieza mecanica y quimica de intercambiadores de calor en centrales nucleares francesas

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, J. t.; Guerra, P.; Carreres, C.

    2013-03-01

    This project was carried out under the frame of the approval of LAINSA as a supplier of EDF in France. The inspection performed on systems called the moisture separator reheaters (GSS) of CPO series reactor of EDF nuclear power plants has shown evidence of significant clogging due to deposits of magnetite inside the tubes of tube bundle. The pressure drop between inlet and outlet of the heating was close to maximum design criterion. This effect could result in equipment damage and loss of plant productivity. The aim of the work was the design, development, approval and implementation of a procedure for un blocking the tubes of the GSS respecting the integrity of materials and ensuring the harmlessness of cleaning procedures. The procedure used was to completely remove magnetite deposits in order to recover a passage diameter and a surface finish equivalent to the origin, thus avoiding the replacement of the GSS and obtaining a considerable reduction of costs. The achieve these objectives we have developed a procedure that is basically a mechanical pre-cleaning of all tubes of the GSS in order to unblock tem, followed by a chemical cleaning where magnetite is dissolved and crawled out of the tube bundle. The main results were: -Corrosion less than 10 microns. 100-110 Kg of magnetite removed by heat exchanger. -Final pressure drop similar to that of new equipment. -Waste water: 70 m{sup 3} per exchanger, which were managed by an authorized waste management company. This procedure has been applied successfully in 14 GSS type heat exchangers in Fessenheim and Bugey nuclear power plants in France between 2009 and 2011. This project demonstrates that the long experience of LAINSA in the Spanish nuclear industry along with the knowledge and experience in chemical cleaning of SOLARCA, have served to successfully work demanding and mature markets such as the French nuclear market, solving the problem of deposits of magnetite with an effective and safe method for the treated

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

    International Nuclear Information System (INIS)

    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.

  12. Experimental studies of thermal and chemical interactions between oxide and silicide nuclear fuels with water

    International Nuclear Information System (INIS)

    Given some transient power/cooling mismatch is a nuclear reactor and its inability to establish the necessary core cooling, energetic fuel-coolant interactions (FCI's commonly called 'vapor explosions') could occur as a result of the core melting and coolant contact. Although a large number of studies have been done on energetic FCI's, very few experiments have been performed with the actual fuel materials postulated to be produced in severe accidents. Because of the scarcity of well-characterized FCI data for uranium allows in noncommercial reactors (cermet and silicide fuels), we have conducted a series of experiments to provide a data base for the foregoing materials. An existing 1-D shock-tube facility was modified to handle depleted radioactive materials (U3O8-Al, and U3Si2-Al). Our objectives have been to determine the effects of the initial fuel composition and temperature and the driving pressure (triggering) on the explosion work output, dynamic pressures, transient temperatures, and the hydrogen production. Experimental results indicate limited energetics, mainly thermal interactions, for these fuel materials as compared to aluminum where more chemical reactions occur between the molten aluminum and water

  13. Experimental studies of thermal and chemical interactions between oxide and silicide nuclear fuels with water

    Energy Technology Data Exchange (ETDEWEB)

    farahani, A.A.; Corradini, M.L. [Univ. of Wisconsi, Madison, WI (United States)

    1995-09-01

    Given some transient power/cooling mismatch is a nuclear reactor and its inability to establish the necessary core cooling, energetic fuel-coolant interactions (FCI`s commonly called `vapor explosions`) could occur as a result of the core melting and coolant contact. Although a large number of studies have been done on energetic FCI`s, very few experiments have been performed with the actual fuel materials postulated to be produced in severe accidents. Because of the scarcity of well-characterized FCI data for uranium allows in noncommercial reactors (cermet and silicide fuels), we have conducted a series of experiments to provide a data base for the foregoing materials. An existing 1-D shock-tube facility was modified to handle depleted radioactive materials (U{sub 3}O{sub 8}-Al, and U{sub 3}Si{sub 2}-Al). Our objectives have been to determine the effects of the initial fuel composition and temperature and the driving pressure (triggering) on the explosion work output, dynamic pressures, transient temperatures, and the hydrogen production. Experimental results indicate limited energetics, mainly thermal interactions, for these fuel materials as compared to aluminum where more chemical reactions occur between the molten aluminum and water.

  14. Estimation of petrophysical and fluid properties using integral transforms in nuclear magnetic resonance.

    Science.gov (United States)

    Gruber, Fred K; Venkataramanan, Lalitha; Habashy, Tarek M; Freed, Denise E

    2013-03-01

    In the past decade, low-field NMR relaxation and diffusion measurements in grossly inhomogeneous fields have been used to characterize properties of porous media, e.g., porosity and permeability. Pulse sequences such as CPMG, inversion and saturation recovery as well as diffusion editing have been used to estimate distribution functions of relaxation times and diffusion. Linear functionals of these distribution functions have been used to predict petro-physical and fluid properties like permeability, viscosity, fluid typing, etc. This paper describes an analysis method using integral transforms to directly compute linear functionals of the distributions of relaxation times and diffusion without first computing the distributions from the measured magnetization data. Different linear functionals of the distribution function can be obtained by choosing appropriate kernels in the integral transforms. There are two significant advantages of this approach over the traditional algorithm involving inversion of the distribution function from the measured data. First, it is a direct linear transform of the data. Thus, in contrast to the traditional analysis which involves inversion of an ill-conditioned, non-linear problem, the estimates from this new method are more accurate. Second, the uncertainty in the linear functional can be obtained in a straight-forward manner as a function of the signal-to-noise ratio (SNR) in the measured data. We demonstrate the performance of this method on simulated data. PMID:23369701

  15. Assessing the risks of nuclear and chemical contamination in the former Soviet Union

    International Nuclear Information System (INIS)

    In the first four chapters the focus is on risk assessment and the role of various segments of the society in defining risk criteria. In Chapter 2, the interface between science, policymaking, and environmental law is addressed. In chapter 3, the importance of including organizational and human factors in risk assessments is discussed. It is noted that risk assessment is also a matter for an informed public. Chapter 4 focuses on the specific application of technology to hazardous waste disposal. The most expensive high-tech equipment may not always be the best to solve a particular disposal problem. In Chapter 5 international efforts to determine the effects of nuclear testing are examined, moving on to question the methods used to define risk criteria. The last four chapters of the book focus on risk assessment and the role of various segments of the society in defining risk criteria. Chapter 6 is an introduction to the work done to assess the environmental and health affects of the 1986 accident at Chernobyl. Also the Ukrainian government's effort to assess additional natural and anthropogenic sources of radioactive contamination is discussed. In chapter 7, the efforts by the International Atomic Energy Agency and other organizations to assess the effects of Chernobyl are examined. The eighth chapter introduces the means by which nongovernmental environmental groups (NGO), e.g. Greenpeace, collect information on environmental threats and the role they play in informing the larger public about them. In this case, the dumping of radioactive waste in the Kara and Barents Seas is examined in detail. In Chapter 9 it is examined how interdisciplinary groups are required to assess the environmental and health effects of the dumping in the Kara and Barents Seas. The issues of reliable data and determining risk in the absence of data are discussed. In the final chapter, the major themes and results of the workshop are summarized, including a set of recommendations for

  16. Nuclear industry - challenges in chemical engineering

    International Nuclear Information System (INIS)

    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.)

  17. Technology of thorium concentrates purification and their transformation in pure nuclear products

    International Nuclear Information System (INIS)

    An experimental study for the purification of thorium concentrates by solvent extraction is presented. The product of purification is appropriate for utilization in the fabrication of nuclear reactor fuel elements. The experiments are carried out in a laboratory scale and the following operations are studied: dissolution, extraction-scrubbing, stripping-scrubbing, thorium oxalate precipitation, and thorium nitrate coagulation

  18. Experimental studies of thermal and chemical interactions between molten aluminum and nuclear dispersion fuels with water

    International Nuclear Information System (INIS)

    Because of the possibility of rapid physical and chemical molten fuel-water interactions during a core melt accident in noncommercial or experimental reactors, it is important to understand the interactions that might occur if these materials were to contact water. An existing vertical 1-D shock tube facility was improved and a gas sampling device to measure the gaseous hydrogen in the upper chamber of the shock tube was designed and built to study the impact of a water column driven downward by a pressurized gas onto both molten aluminum (6061 alloy) and oxide and silicide depleted nuclear dispersion fuels in aluminum matrices. The experiments were carried out with melt temperatures initially at 750 to 1,000 C and water at room temperature and driving pressures of 0.5 and 1 MPa. Very high transient pressures, in many cases even larger than the thermodynamic critical pressure of the water (∼ 20 MPa), were generated due to the interactions between the water and the crucible and its contents. The molten aluminum always reacted chemically with the water but the reaction did not increase consistently with increasing melt temperature. An aluminum ignition occurred when water at room temperature impacted 28.48 grams of molten aluminum at 980.3 C causing transient pressures greater than 69 MPa. No signs of aluminum ignition were observed in any of the experiments with the depleted nuclear dispersion fuels, U3O8-Al and U3Si2-Al. The greater was the molten aluminum-water chemical reaction, the finer was the debris recovered for a given set of initial conditions. Larger coolant velocities (larger driving pressures) resulted in more melt fragmentation but did not result in more molten aluminum-water chemical reaction. Decreasing the water temperature also resulted in more melt fragmentation and did not suppress the molten aluminum-water chemical reaction

  19. Analysis of Palo Verde Nuclear Generating Station unit auxiliary transformer fire

    International Nuclear Information System (INIS)

    On July 6, 1988, the Unit 1 Unit Auxiliary Transformer (UAT) catastrophically failed resulting in a major oil fire. A secondary fire, due to re-energization of a non-class 1E 13.8 KV bus, damaged turbine building switchgear and bus components. The estimated cost of direct damage is approximately $3,400,000. The initiating event leading to the UAT failure was most likely a phase to ground fault in a non-class 1E 13.8 KV bus. The initial fault condition resulted in arcing which propagated into a three phase to ground fault which lead to winding failure and rupture of the UAT. The transformer oil fire was controlled and extinguished by passive and active fire protection features and the plant fire department. The switchgear fire was extinguished by the plant fire department utilizing a CO2 hose reel system. 1 fig

  20. Progress report on nuclear science and technology in China (Vol.2). Proceedings of academic annual meeting of China Nuclear Society in 2011, No.5--nuclear chemical engineering sub-volume

    International Nuclear Information System (INIS)

    Progress report on nuclear science and technology in China (Vol. 2) includes 698 articles which were presented on the second national academic annual meeting of China Nuclear Society. There are 10 books totally. This is the fifth one, the content is about nuclear chemical engineering.

  1. Generation of low-frequency electric and magnetic fields during large- scale chemical and nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Adushkin, V.V. [Academy of Sciences, Moscow (Russian Federation). Inst. for Dynamics of the Geospheres; Dubinya, V.A.; Karaseva, V.A.; Soloviev, S.P.; Surkov, V.V. [Lawrence Livermore National Lab., CA (United States)

    1995-06-01

    We discuss the main parameters of the electric field in the surface layer of the atmosphere and the results of the investigations of the natural electric field variations. Experimental investigations of the electromagnetic field for explosions in air are presented. Electromagnetic signals generated by underground nuclear and chemical explosions are discussed and explosions for 1976--1991 are listed. Long term anomalies of the earth`s electromagnetic field in the vicinity of underground explosions were also investigated. Study of the phenomenon of the irreversible shock magnetization showed that in the zone nearest to the explosion the quasistatic magnetic field decreases in inverse proportion to the distance.

  2. Acceptance of nuclear power: The Fukushima effect

    International Nuclear Information System (INIS)

    Utilizing a longitudinal study design, the impact of the 2011 accident in Fukushima on acceptance of nuclear power and the evaluation of several scenarios with different percentages of nuclear power were examined. Mail surveys were conducted in the German-speaking part of Switzerland. The first survey took place before the accident in Fukushima (Autumn 2010), the second survey immediately after the accident (March 2011), and the third survey half a year after the accident (October 2011). A sample of 463 persons participated in all three surveys. The accident had a negative impact on the acceptance of nuclear power. The mean change was moderate, and high correlations between the measurement points were observed. Overall, participants thus showed rather stable attitudes towards nuclear power across the three measurement waves. Results of the present study demonstrate the importance of prior beliefs and attitudes for the interpretation of an accident. The evaluation of the various scenarios was strongly influenced by participants’ pre-Fukushima attitudes towards nuclear power. - Highlights: ► Longitudinal studies are important for risk perception research. ► The accident in Fukushima had only a moderate impact on acceptance. ► Acceptance of nuclear power before and after Fukushima was highly correlated. ► People have stable attitudes towards nuclear power

  3. Nuclear Winter: Uncertainties Surround the Long-Term Effects of Nuclear War. Report to the Congress.

    Science.gov (United States)

    General Accounting Office, Washington, DC.

    Nuclear winter, a term used to describe potential long-term climate and environmental effects of nuclear war, has been a subject of debate and controversy. This report examines and presents scientific and policy implications of nuclear winter. Contents include: (1) an executive summary (highlighting previous and current studies on the topic); (2)…

  4. Size-dependent chemical transformation, structural phase-change, and optical properties of nanowires

    OpenAIRE

    Piccione, Brian; Agarwal, Rahul; Jung, Yeonwoong; Agarwal, Ritesh

    2013-01-01

    Nanowires offer a unique approach for the bottom up assembly of electronic and photonic devices with the potential of integrating photonics with existing technologies. The anisotropic geometry and mesoscopic length scales of nanowires also make them very interesting systems to study a variety of size-dependent phenomenon where finite size effects become important. We will discuss the intriguing size-dependent properties of nanowire systems with diameters in the 5 – 300 nm range, where finite ...

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

    International Nuclear Information System (INIS)

    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

  6. Comparative nuclear effects of biomedical interest. Civil effects study

    Energy Technology Data Exchange (ETDEWEB)

    White, C.S.; Bowen, I.G.; Richmond, D.R.; Corsbie, R.L.

    1961-01-12

    Selected physical and biological data bearing upon the environmental variations created by nuclear explosions are presented in simplified form. Emphasis is placed upon the ``early`` consequences of exposure to blast, thermal radiation, and ionizing radiation to elucidate the comparative ranges of the major effects as they vary with explosive yield and as they contribute to the total hazard to man. A section containing brief definitions of the terminology employed is followed by a section that utilizes text and tabular material to set forth events that follow nuclear explosions and the varied responses of exposed physical and biological materials. Finally, selected quantitative weapons-effects data in graphic and tabular form are presented over a wide range of explosive yields to show the relative distances from Ground Zero affected by significant levels of blast overpressures, thermal fluxes, and initial and residual penetrating ionizing radiations. However, only the ``early`` rather than the ``late`` effects of the latter are considered.

  7. Modeling of radiation effects on nuclear waste package materials

    International Nuclear Information System (INIS)

    A methodology is developed for the assessment of radiation effects on nuclear waste package materials. An assessment of the current status of understanding with regard to waste package materials and their behavior in radiation environments is presented. The methodology is used to make prediction as to the chemically induced changes in the groundwater surrounding nuclear waste packages in a repository in tuff. The predictions indicate that mechanisms not currently being pursued by the Department of Energy may be a factor in the long-term performance of nuclear waste packages. The methodology embodies a physical model of the effects of radiation on aqueous solutions. Coupled to the physical model is a method for analyzing the complex nature of the physical model using adjoint sensitivity analysis. The sensitivity aid in both the physical understanding of the processes involved as well as aiding in eliminating portions of the model that have no bearing on the desired results. A computer implementation of the methodology is provided. 128 refs

  8. Terror weapons. Ridding the world of nuclear, biological and chemical weapons - Commission on mass destruction weapons

    International Nuclear Information System (INIS)

    This book approaches in 8 chapters the ambitious challenge of ridding the world of all mass destruction weapons: 1 - re-launching disarmament; 2 - terror weapons: nature of threats and answers (weakness of traditional answers, counter-proliferation); 3 - nuclear weapons: preventing proliferation and terrorism, reducing threat and nuclear weapons number, from regulation to banning); 4 - biological or toxin weapons; 5 - chemical weapons; 6 - vectors, anti-missile defenses and space weapons; 7 - exports control, international assistance and non-governmental actors; 8 - respect, verification, enforcement and role of the United Nations. The recommendations and works of the Commission are presented in appendix together with the declaration adopted on April 30, 2009. (J.S.)

  9. Thermogravimetric analysis of petroleum asphaltenes along with estimation of average chemical structure by nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Combining with the 1H and 13C nuclear magnetic resonance (NMR) determinations, elemental analysis and molecular weight measurement, average molecular formula of the chemical unit for the asphaltenes from Chinese Daqing crude oil were calculated. Thermal pyrolysis kinetics of the asphaltenes had been studied using thermogravimetric analysis (TGA). The distributed activation energy model (DAEM) was used to analyze these complex systems. The results show that the peak activation energy for pyrolysis of the asphaltenes is 245 kJ mol-1 and the pre-exponential factor is 5.88 x 1014 s-1. The DAEM method presented reasonably good results of the prediction of the weight loss curves. A linear relationship can be found from the plots of logarithm of the pre-exponential factor against the activation energy at selected conversion values. This phenomenon known as the compensation effect was explained and it was in agreement with the estimated chemical structure determined by NMR

  10. THE EFFECT OF DRAINAGE ON CHEMICAL ELEMENTS CONTENT OF MARSH

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper takes marsh in the Sanjiang Plain as an example in order to research the effect of draining on the chemical elements in marsh. The Sanjiang Ecological Test Station of Mire and Uetland serves as the resarch base. The authors selected soil samples in the Sanjiang Plain (the top and the end of the drain, marsh soil and degeneration marsh soil), mainly analyzed contents of main ions (HCO3-, Cl-, SO42-and NO3-), main heavy metals (Fe, Mn, Znand Cu), nutritive elements (N, P,K), organic matter and pH value. By testing these samples as above, the paper initially researches the effect on chemical elements content by draining by the means of the contrast of chemical elements contents between marsh soil and degenerative marsh soil and different characteristics of marsh soil elements. Results show that a lot of chemical elements had been lost because of draining.

  11. The Effects of Nuclear Terrorism: Fizzles

    OpenAIRE

    Liolios, Theodore

    2002-01-01

    The September 11 terrorist attack against America has caused a lot of concern to the American public and the entire world, which is suspecting a new attack sooner or later. The most frightening scenario is the one involving the detonation of a nuclear device at the heart of a large metropolitan city. Unless the terrorists are in possession of a fully assembled modern nuclear weapons it is very likely that they will possess a crude nuclear device which has been assembled in a terrorist camp by...

  12. Effects of nuclear war on health and health services

    International Nuclear Information System (INIS)

    This report reviews the findings since 1987 in the field of research related to the possible impact of nuclear war and nuclear explosions on health and health services. An annex contains the finding and conclusions of a 1989 United Nations study on the climatic and other effects of nuclear war. 1 tab

  13. Application study of nuclear technologies for integration chemical, biological and radiological technology

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jae Kon; Han, M. H.; Kim, Y. H.; Yang, J. E.; Jung, K. S.; Cha, H. K.; Moon, J.; La, K. H

    2001-02-01

    The projects are suggested the method to maximize the technology and research results which are being carried out by KAERI on the nuclear field. The study presents 1)the technology to rapidly and accurately determine and the nature of contamination, 2) the technology to predict the spread of contaminant and the magnitude of damage, and 3) the expert-aided decision making technology to identify the optimum counter-measures. And the solutions are also suggested the application to military technology in Chemical, Biological and Radiation field. In addition, I hope this kind of cooperation model come to be the good case of military civilian research harmony to improve the national competition capability.

  14. Application study of nuclear technologies for integration chemical, biological and radiological technology

    International Nuclear Information System (INIS)

    The projects are suggested the method to maximize the technology and research results which are being carried out by KAERI on the nuclear field. The study presents 1)the technology to rapidly and accurately determine and the nature of contamination, 2) the technology to predict the spread of contaminant and the magnitude of damage, and 3) the expert-aided decision making technology to identify the optimum counter-measures. And the solutions are also suggested the application to military technology in Chemical, Biological and Radiation field. In addition, I hope this kind of cooperation model come to be the good case of military civilian research harmony to improve the national competition capability

  15. The effect of point defects on the martensitic phase transformation

    International Nuclear Information System (INIS)

    Martensitic Ni-Ti was observed to transform to the austenitic phase due to defects introduced either by ion or electron irradiations at a temperature where the martensitic phase is normally stable. The phenomenon was studied by molecular dynamics simulation in the Ni-Al shape memory alloy system where theoretical model potentials are well established. The simulations show that defects reduce the martensitic phase transition (MPT) temperature, and the high temperature austenite phase is favored. In the Ni-Al system, the difference of phase transition temperatures with and without defects is about 100 K

  16. The effect of point defects on the martensitic phase transformation

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jian [School of Science, Huzhou University, Zhejiang 313000 (China)]. E-mail: jian@hutc.zj.cn; Wang Yu [School of Science, Huzhou University, Zhejiang 313000 (China); Schaublin, R. [CRPP-EPFL Fusion Technology Materials, CH-5232 Villigen PSI (Switzerland); Abromeit, C. [Hahn-Meitner-Institut Berlin GmbH, Glienicker Str. 100, D-14109 Berlin (Germany); Gotthardt, Rolf [Institute of Physics of Complex Matter (IPMC), Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2006-11-25

    Martensitic Ni-Ti was observed to transform to the austenitic phase due to defects introduced either by ion or electron irradiations at a temperature where the martensitic phase is normally stable. The phenomenon was studied by molecular dynamics simulation in the Ni-Al shape memory alloy system where theoretical model potentials are well established. The simulations show that defects reduce the martensitic phase transition (MPT) temperature, and the high temperature austenite phase is favored. In the Ni-Al system, the difference of phase transition temperatures with and without defects is about 100 K.

  17. Project research on nuclear physical and chemical characteristics of actinide nuclides

    International Nuclear Information System (INIS)

    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.)

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

    International Nuclear Information System (INIS)

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

  19. Direct Evidence of Washing out of Nuclear Shell Effects

    CERN Document Server

    Chaudhuri, A; Banerjee, K; Bhattacharya, S; Sadhukhan, Jhilam; Bhattacharya, C; Kundu, S; Meena, J K; Mukherjee, G; Pandey, R; Rana, T K; Roy, P; Roy, T; Srivastava, V; Bhattacharya, P

    2015-01-01

    Constraining excitation energy at which nuclear shell effect washes out has important implications on the production of super heavy elements and many other fields of nuclear physics research. We report the fission fragment mass distribution in alpha induced reaction on an actinide target for wide excitation range in close energy interval and show direct evidence that nuclear shell effect washes out at excitation energy ~40 MeV. Calculation shows that second peak of the ?fission barrier also vanishes around similar excitation energy.

  20. Natural radiation, nuclear wastes and chemical pollutants

    International Nuclear Information System (INIS)

    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

  1. Impacts on health and safety from transfer/consolidation of nuclear materials and hazardous chemicals

    International Nuclear Information System (INIS)

    Environmental restoration plans at the US Department of Energy (USDOE) Hanford Site calls for transfer/consolidation of ''targets/threats,'' namely nuclear materials and hazardous chemicals. Reductions in the health and safety hazards will depend on the plans implemented. Pacific Northwest Laboratory (PNL) estimated these potential impacts, assuming implementation of the current reference plan and employing ongoing risk and safety analyses. The results indicated the potential for ''significant'' reductions in health and safety hazards in the long term (> 25 years) and a potentially ''noteworthy'' reduction in health hazard in the short term (≤ 25 years)

  2. Sub-Thermal Effects at the Radiation-Thermal Transformations of Organic Fuels

    International Nuclear Information System (INIS)

    Full text: The regularities of the radiation-thermal transformations of coals , anthracite, peat, heavy oil fractions (gasoil, fuel-oil, tar, bitumen) and oil-bituminous rocks are studied in the Institute of Radiation Problems for 1985-2012. As a radiation the gamma-rays of isotope sources Co-60, electron beam of electron accelerators of ELIT-1 and ELU-4 are used. Parameters of processes varied in following limits: dose rate 0.4-2000 Gy/s, absorbed dose 0.7- 800 kGy, temperature 40-700C. As products are identified: hydrogen, carbon monoxide, hydrocarbons C1-C7, high-molecular olefins, active carbon and liquid fuel. For studying physical and chemical processes at the radiation-thermal transformation of organic fuels are used methods: a chromatography, IR-spectroscopy, ESR- spectroscopy, derivatography, chemical methods of the liquid analysis, etc. Studying of kinetics and mechanism of proceeding processes was studied on an example model hydrocarbons- heptane and pentadecane. It is applied calculation methods for definition of chemical reactions rates on the basis of the offered kinetic model and are received satisfactory consent between calculation and experimental results. It has been shown that sub-thermal effect at the radiation-thermal decomposition of organic fuels is function of temperature and dose rate. In quantity of sub-thermal effect the certain contribution gives energy of activation of thermal decomposition of organic fuel and reaction of separation, and also constants of rate for radical recombination processes, etc. The dose rate and temperature are double influence on quantity of sub-thermal effects. On the one hand raising of rate of separation reactions (as a result of temperature rise) increases an yield of products, on other hand-raises of rate of pure thermal reactions of decomposition. Dose rate also doubly influences on sub-thermal effects. So, with increase of dose rate of radiation the concentration of active particles grows, at the same

  3. Effect of plastic behaviour of steels during martensitic transformation on quenching stress initiation

    International Nuclear Information System (INIS)

    This research thesis reports the study of the effects of a steel martensitic transformation on the mechanisms producing internal stresses during quench. After having reported a bibliographical study on tests of qualitative and quantitative prediction (presentation of several models) of the genesis of internal stresses during quench, the author reports the study of the alloy behaviour during cooling and presents the basis of a model of prediction of internal stresses. The next part addresses the determination of the influence of martensitic transformation on the evolution of stresses during quench. The last part reports the taking into account of the effect of stress-phase transformation interaction in the calculation of internal stresses

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

    International Nuclear Information System (INIS)

    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 m3 per tank), 5 storage tanks for chemicals (capacity 0.5 m3 per tank), 2 mixing reactors (capacity 0.5 m3 per reactor), 1 storage tank for supernatant solution (capacity 1 m3), and 1 storage tank for sludge (capacity 1 m3)

  5. A method for the amplification of chemically induced transformation in C3H/10T1/2 clone 8 cells: its use as a potential screening assay.

    Science.gov (United States)

    Schechtman, L M; Kiss, E; McCarvill, J; Nims, R; Kouri, R E; Lubet, R A

    1987-09-01

    A method has been developed by which to amplify expression of phenotypic transformation of C3H/10T1/2 clone 8 mouse embryo cells not otherwise observed in the standard transformation assay. The expression of transformed foci was amplified by subcultivating chemically treated target cells after they had reached confluence and replating them at subconfluent cell densities. Conditions leading to the expression of the highest numbers of transformed foci include a) a cell seeding density for chemical treatment of 1 X 10(4) cells/dish, b) subculture 4 weeks after treatment, and c) replating cells at a density of 2 X 10(5) cells/-dish. Agents capable of inducing transformation in the standard assay (e.g., 4,4'-bis(dimethylamino)benzophenone, benzo[a]pyrene, 7,12-dimethylbenz[a]anthracene, and others) also yielded transformation in the replating assay. The more marginal transforming activities of chemicals such as ethyl methanesulfonate, 7-(bromomethyl)-12-methylbenz[a]anthracene, and N-methyl-N'-nitro-N-nitrosoguanidine were enhanced by the amplification procedure. Compounds that failed to elicit focal transformation in the standard assay (e.g., dibenz[a,h]anthracene, Tris(2,3-dibromopropyl) phosphate, lead acetate, benzidine, propyleneimine, N-hydroxy-2-fluorenylacetamide, and numerous other compounds of various chemical classes) induced significant levels of phenotypic transformation upon amplification. Noncarcinogens (e.g., phenanthrene, anthracene, 2-aminobiphenyl, cycloheximide, and others) failed to cause significant phenotypic transformation even when cells were replated. To further enhance the applicability of this new replating system, an exogenous source of metabolic activation was added: a 9,000 X g supernatant from Aroclor 1254-induced rat hepatic S-9. This activation system was found a) to be only minimally cytotoxic by itself and b) to be able to mediate NADPH-dependent, dose-dependent toxicity, and transformation by activating the procarcinogens

  6. On radiation-chemical mechanism of chlorine generation in the nuclear cavities

    International Nuclear Information System (INIS)

    The work the attempt for theoretical estimation of possible release of chlorine from halogen, materials of salt thickness in the condition of radioactive emanation effect from fission fragments concentrated on the bottom and the places of non-watery underground nuclear explosion caverns is made. The theoretical calculations on derivable chlorine volumes determination in the result of post-explosion radiolysis of way an accommodating nuclear cavities showing that at an explosion capacity 10 kt of trinitrotoluol equivalent could be selected up to 300 kg of gas-like chlorine, and at help of explosion capacity 100 kt - up to 3000 kg

  7. Chemical cleaning of porous stainless steel cross-flow filter elements for nuclear waste applications

    International Nuclear Information System (INIS)

    The Waste Treatment and Immobilization Plant (WTP) currently under construction for treatment of High-Level Waste (HLW) at the Hanford Site will rely on cross-flow ultrafiltration to provide solids-liquid separation as a core part of the treatment process. To optimize process throughput, periodic chemical cleaning of the porous stainless steel filter elements has been incorporated into the design of the plant. It is currently specified that chemical cleaning with nitric acid will occur after significant irreversible membrane fouling is observed. Irreversible fouling is defined as fouling that cannot be removed by backpulsing the filter. PNNL has investigated chemical cleaning processes as part of integrated tests with HLW simulants and with actual Hanford tank wastes. To quantify the effectiveness of chemical cleaning, the residual membrane resistance after cleaning was compared against the initial membrane resistance for each test in a series of long-term fouling tests. The impact of the small amount of residual resistance in these tests could not be separated from other parameters and the historical benchmark of >1 GPM/ft2 for clean water flux was determined to be an adequate metric for chemical cleaning. Using the results from these tests, a process optimization strategy is presented suggesting that for the simulant material under test, the value of chemical cleaning may be suspect. The period of enhanced filtration may not be enough to offset the down time required for chemical cleaning, without respect to the other associated costs.

  8. Chemical cleaning of porous stainless steel cross-flow filter elements for nuclear waste applications

    Energy Technology Data Exchange (ETDEWEB)

    Billing, Justin M.; Daniel, Richard C.; Hallen, Richard T.; Schonewill, Philip P.; Shimskey, Rick W.; Peterson, Reid A.

    2011-05-10

    The Waste Treatment and Immobilization Plant (WTP) currently under construction for treatment of High-Level Waste (HLW) at the Hanford Site will rely on cross-flow ultrafiltration to provide solids-liquid separation as a core part of the treatment process. To optimize process throughput, periodic chemical cleaning of the porous stainless steel filter elements has been incorporated into the design of the plant. It is currently specified that chemical cleaning with nitric acid will occur after significant irreversible membrane fouling is observed. Irreversible fouling is defined as fouling that cannot be removed by backpulsing the filter. PNNL has investigated chemical cleaning processes as part of integrated tests with HLW simulants and with actual Hanford tank wastes. To quantify the effectiveness of chemical cleaning, the residual membrane resistance after cleaning was compared against the initial membrane resistance for each test in a series of long-term fouling tests. The impact of the small amount of residual resistance in these tests could not be separated from other parameters and the historical benchmark of >1 GPM/ft2 for clean water flux was determined to be an adequate metric for chemical cleaning. Using the results from these tests, a process optimization strategy is presented suggesting that for the simulant material under test, the value of chemical cleaning may be suspect. The period of enhanced filtration may not be enough to offset the down time required for chemical cleaning, without respect to the other associated costs.

  9. Effects of toxicity, aeration, and reductant supply on trichloroethylene transformation by a mixed methanotrophic culture.

    OpenAIRE

    Alvarez-Cohen, L; McCarty, P L

    1991-01-01

    The trichloroethylene (TCE) transformation rate and capacity of a mixed methanotrophic culture at room temperature were measured to determine the effects of time without methane (resting), use of an alternative energy source (formate), aeration, and toxicity of TCE and its transformation products. The initial specific TCE transformation rate of resting cells was 0.6 mg of TCE per mg of cells per day, and they had a finite TCE transformation capacity of 0.036 mg of TCE per mg of cells. Formate...

  10. Subspaces of FMmlet transform

    Institute of Scientific and Technical Information of China (English)

    邹红星; 戴琼海; 赵克; 陈桂明; 李衍达

    2002-01-01

    The subspaces of FMmlet transform are investigated.It is shown that some of the existing transforms like the Fourier transform,short-time Fourier transform,Gabor transform,wavelet transform,chirplet transform,the mean of signal,and the FM-1let transform,and the butterfly subspace are all special cases of FMmlet transform.Therefore the FMmlet transform is more flexible for delineating both the linear and nonlinear time-varying structures of a signal.

  11. Effects of industrial chemicals and radioactive materials in biological systems

    International Nuclear Information System (INIS)

    Much has been written on the effects of radiation and toxic chemicals on biological systems. In this communication general considerations regarding these topics will be discussed very briefly; the major emphasis will be focused on the effects of chemicals, namely ethyl methane sulfonate (EMS) on Amoeba, Advantages to the use of amoeba for studying the effects of radiation and chemicals include the following: large mononucleate unicellular organisms having a long generation time; opportunity to study cellular organelles and biochemical and genetic alterations in a single cell system; and a long cell cycle, the stages of which can be synchronized without resorting to chemical treatment or temperature shock and thereby readily permitting study at defined stages of the cell's life cycle. This, in turn, is discussed in light of current disposal methods for this type of waste and how it might be safely disposed of

  12. 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.

  13. The Effects of Managers Transformational Leadership Style on Employees Organizational Commitment

    OpenAIRE

    Derya Kara

    2012-01-01

    This study investigates the effect of managers’ transformational leadership styles on the employees’ organizational commitment in the hotel industry. The study was conducted on 443 employees in five-star hotels in Turkey. First, the correlation analysis conducted between organizational commitment and transformational leadership styles. The results showed that there is a positive, moderate level of correlation between employee organizational commitment and transformational leadership styles (i...

  14. Seismic identification analyses of cavity decoupled nuclear and chemical explosions. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, J.R.; Barker, B.W.

    1994-01-01

    Successful seismic monitoring of any eventual Comprehensive Test Ban Treaty will require development of a capability to identify signals from small cavity decoupled nuclear explosions from among numerous signals to be expected from earthquakes, rockbursts and chemical explosion (CE) events of comparable magnitude. The investigations summarized in this report focus on preliminary studies which have been carried out in an attempt to distinguish between decoupled nuclear explosions and CE events though analyses of observed and simulated seismic data for these two source types in both the U.S. and former Soviet Union. Near-regional seismic data recorded from the U.S. nuclear cavity decoupling test STERLING and the nearby tamped CE test STERLING HE are compared in Section II in an attempt to identify diagnostic differences between these two source types. This is followed in Section III by an analysis in which short-period P wave data recorded at NORSAR from Soviet nuclear tests conducted in salt cavities at Azgir site north of the Caspian Sea are systematically compared with corresponding data recorded at the same stations from presumed CE events of comparable size which have been located in the vicinity of Azgir site. In Secion IV, broadband seismic data recorded at near-regional Soviet stations from an Azgir nuclear cavity decoupling test are theoretically scaled to 1 kt fully decoupled level and compared with data recorded at the nearby IRIS station KIV from well-documented CE events. The results of these preliminary comparison studies indicate that seismic discrimination between these two explosion source types is not trivial and suggest that a reliable discrimination strategy will have to be based on detailed analysis of data.

  15. Effect of sun radiation on the thermal behavior of distribution transformer

    International Nuclear Information System (INIS)

    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.

  16. Physico-chemical characterisation of radionuclides discharged from a nuclear establishment

    International Nuclear Information System (INIS)

    Low-level liquid radioactive wastes are routinely discharged, under authorisation, from nuclear establishments into UK coastal waters. Samples from two separate effluent streams (SIXEP and seatank) arising from the British Nuclear Fuels plc reprocessing plant at Sellafield have been collected on a number of occasions to compare differences in their physico-chemical composition. The most significant amounts of radionuclides in SIXEP and seatank effluents were observed in the solution and particulate phases, respectively. Laboratory experiments have been carried out to determine the colloidal size distribution of a suite of radionuclides in each of the effluent samples using the ultrafiltration technique. Results suggest that colloidal forms of individual radionuclides, originating from the solution phase, are more likely to occur in SIXEP rather than in seatank effluent. Additional size fractionation experiments were carried out to investigate the likely persistence of radiocolloids following dilution of effluents into seawater. The extent of radionuclides associated with colloids in SIXEP effluent appeared to be reduced following dilution. Particulate material originating from seatank effluent, upon dilution, was also identified as a source (albeit small) of colloidally bound radionuclides. Having accounted for differences between effluent streams, including discharge levels, the contribution of individual physico-chemical forms of radionuclides from the Sellafield source is discussed

  17. 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.

  18. Chemical transformation kinetics of Pu and Am in soils of Belarus

    International Nuclear Information System (INIS)

    On the basis of available experimental data the constant of destruction rate of fuel particles and constants of formation rate of plutonium and americium fulvates which determine migration kinetics of metals - ions in a soil - plant system are calculated. The long-term forecast of accumulation of mobile forms of Pu and Am in soil is carried out. (authors)

  19. Nitrogen transformations in wetlands: Effects of water flow patterns

    Energy Technology Data Exchange (ETDEWEB)

    Davidsson, T.

    1997-11-01

    In this thesis, I have studied nitrogen turnover processes in water meadows. A water meadow is a wetland where water infiltrates through the soil of a grassland field. It is hypothesized that infiltration of water through the soil matrix promotes nutrient transformations compared to surface flow of water, by increasing the contact between water, nutrients, soil organic matter and bacteria. I have studied how the balance between nitrogen removal (denitrification, assimilative uptake, adsorption) and release (mineralization, desorption) processes are affected by water flow characteristics. Mass balance studies and direct denitrification measurements at two field sites showed that, although denitrification was high, net nitrogen removal in the water meadows was poor. This was due to release of ammonium and dissolved organic nitrogen (DON) from the soils. In laboratory studies, using {sup 15}N isotope techniques, I have shown that nitrogen turnover is considerably affected by hydrological conditions and by soil type. Infiltration increased virtually all the nitrogen processes, due to deeper penetration of nitrate and oxygen, and extended zones of turnover processes. On the contrary, soils and sediments with surface water flow, diffusion is the main transfer mechanism. The relation between release and removal processes sometimes resulted in shifts towards net nitrogen production. This occurred in infiltration treatments when ammonium efflux was high in relation to denitrification. It was concluded that ammonium and DON was of soil origin and hence not a product of dissimilatory nitrate reduction to ammonium. Both denitrification potential and mineralization rates were higher in peaty than in sandy soil. Vertical or horizontal subsurface flow is substantial in many wetland types, such as riparian zones, tidal salt marshes, fens, root-zone systems and water meadows. Moreover, any environment where aquatic and terrestrial ecosystems meet, and where water level fluctuates

  20. Fouling of nuclear steam generators: fundamental studies, operating experience and remedial measures using chemical additives

    International Nuclear Information System (INIS)

    Fouling remains a potentially serious issue that if left unchecked can lead to degradation of the safety and performance of nuclear steam generators (SGs). It has been demonstrated that the majority of the corrosion product transported with the feed water to the SGs accumulates in the SG on the tube-bundle. By increasing the risk of tube failure and acting as a barrier to heat transfer, deposit on the tube bundle has the potential to impair the ability of the SG to perform its two safety-critical roles: provision of a barrier to the release of radioactivity from the reactor coolant and removal of heat from the primary coolant during power operation and under certain post accident scenarios. Thus, it is imperative to develop improved ways to mitigate SG fouling for the long-term safe, reliable and economic performance of nuclear power plants (NPPs). This paper provides an overview of our current understanding of the mechanisms by which deposit accumulates on the secondary side of the SG, how this accumulation affects SG performance and how accumulation of deposit can be mitigated using chemical additives to the secondary heat-transport system. The paper concludes with some key questions that remain to be addressed to further advance our knowledge of deposit accumulation and how it can be controlled to maintain safe, economic performance of nuclear SGs. (author)

  1. Experimental and computational investigation of the effect of phase transformation on fracture parameters of an SMA

    Science.gov (United States)

    Haghgouyan, Behrouz; Shafaghi, Nima; Aydıner, C. Can; Anlas, Gunay

    2016-07-01

    A comprehensive, multi-method experimental characterization of fracture is conducted on shape memory alloy NiTi that exhibits superelasticity due to austenite-to-martensite stress induced phase transformation. This characterization includes (i) load-based measurement of critical stress intensity factor (K max) using ASTM standard E399, (ii) measurement of crack tip opening displacement (CTOD) per ASTM standard E1290, (iii) the digital image correlation (DIC) characterization of the transformation zone as well as the displacement-field based measurement of K max from the DIC data. Samples have also been tested at T = 100 °C to suppress the martensitic transformation to investigate transformation toughening. The experimental investigation is complemented with finite element (FE) analysis that uses Auricchio–Taylor–Lubliner constitutive model. A direct observation with DIC revealed a small scale transformation (K-dominance). K max of the transforming material is higher than that of the transformation-suppressed material tested at 100 °C, suggesting transformation toughening. At 100 °C, the material becomes quite brittle with a very small crack-tip plastic zone when the transformation mechanism is blocked. By measures of critical CTOD, the gap widens even more between the superelastic and transformation-suppressed cases, particularly because of the side effect that, in this very interesting material, material modulus increases with temperature. Evaluating the transformation zone from the DIC strains with reference to the uniaxial stress–strain curve, an equivalent strain form is proposed in conjunction with the plane stress FE prediction.

  2. Effect of Aluminum and Silicon on Transformation Induced Plasticity of the TRIP Steel

    Institute of Scientific and Technical Information of China (English)

    Lin LI; B.C. De Cooman; P. Wollants; Yanlin HE; Xiaodong ZHOU

    2004-01-01

    With the sublattice model, equilibrium compositions of ferrite (α) and austenite (γ) phases, as well as the volume percent of austenite (γ) at 780℃ in different TRIP steels were calculated. Concentration profiles of carbon, Mn, Al and Si in the steels were also estimated under the lattice fixed frame of reference so as to understand the complex mechanical behavior of TRIP steels after different isothermal bainitic transformation treatments. The effect of Si and Mn on transformation induced plasticity (TRIP) was discussed according to thermodynamic and kinetic analyses. It is recognized that Al also induces phase transformation in the steels but its TRIP effect is not as strong as that of Si.

  3. Safety criteria for nuclear chemical plants

    International Nuclear Information System (INIS)

    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.)

  4. Nuclear chemical mining for copper recovery

    International Nuclear Information System (INIS)

    To meet projected domestic demand for copper, deeper ore deposits will have to be exploited and a technology developed for processing these ores. LLL has investigated combining nuclear technology and in situ leaching to recover copper ores from deposits too deep to be mined economically by conventional techniques. The chemical mining concept involves emplacing nuclear explosives below the water table in a deep-lying copper deposit, detonating these explosives to rubblize the rock, and then passing oxygen and water through the rubblized zone to leach out the copper as copper sulfate. The copper sulfate is then brought to the surface where liquid ion exchange and electrowinning are used to remove the copper. Technical evaluations of this chemical mining process have been favorable. In 1973, LLL teamed with the Kennecott Copper Corporation and ERDA to consider the feasibility of commercializing the process. The resulting joint study affirmed the technical feasibility of nuclear chemical mining and identified the process uncertainties that must be resolved before its commercial feasibility can be assured

  5. Environmental transformation of mercury released from gold mining and its implications on human health in Tanzania, studied using nuclear techniques

    International Nuclear Information System (INIS)

    Research work concentrated on the following field and/or laboratory investigations: i) assessment of Hg contamination levels in selected environmental media in the Lake Victoria goldfields, ii) the study of lichens as a suitable bioindicator for atmospheric Hg contamination in small-scale gold mining areas, iii) dynamics of Hg transformation and partition of Hg species in gold mine tailings-water systems contaminated with elemental mercury, iv) mineralogical and chemical characterization of mine tailings, river sediment, lateritic soils in relation to Hg mobility under tropical conditions, v) the effect of aeration/oxygenation and decrease of moisture content on MeHg levels in tropical soil and, iv) methylation of Hg in SOIL-1 inter-comparison sample from the IAEA. Hg contamination was highest in gold mine tailings (165-232 μg/g) from amalgamation ponds but relatively low in contaminated river sediments (6-0.5 μg/g) in the study areas. The dispersion of Hg in river sediments at the Mugusu mine decreased rapidly from 6 μg/g near the gold ore processing site to <0.1 μg/g about 9 km downstream. The highest Hg levels were associated with the grain-size fraction <212 μm in the sediments. Fish mercury levels in 8 fish species representing different trophic levels from the Nungwe Bay in the Victoria lake were generally low, <50 ng/g (w.w.), which indicated insignificant levels of contamination and/or little bioavailability of Hg in that lake region. Mercury concentrations in the Parmelia lichen from Mugusu, Imweru, Rwamagaza and Buckreef gold mine areas, southwest of the Lake Victoria, ranged from 3.1 to 0.07 μg/g, the highest concentrations being recorded close to gold processing stations. The lichens from areas outside the goldfields had the lowest Hg levels in the range 0.05-0.10 μg/g (mean 0.07 μg/g). Investigations of Hg transformation in gold mine tailings from the Rwamagaza mine revealed exceptionally high MeHg contents (629-710 ng/g as Hg), which indicated

  6. The Effect of Transformational Leadership Behavior on Organizational Culture: An Application in Pharmaceutical Industry

    OpenAIRE

    Sinem Aydogdu; Baris Asikgil

    2011-01-01

    In this study, conducted on 96 employees from production sector in a pharmaceutical company, the effect of transformational leadership behavior on organizational culture is investigated to determine statistically significant relations. The results of the study support the hypotheses. Transformational leadership behavior has a positive and significant correlation between the components of organizational culture such as long / short term orientation, masculinity / feminity, power distance, indi...

  7. Climate-chemical interactions and greenhouse effects of trace gases

    Science.gov (United States)

    Shi, Guang-Yu; Fan, Xiao-Biao

    1994-01-01

    A completely coupled one-dimensional radiative-convective (RC) and photochemical-diffusion (PC) model has been developed recently and used to study the climate-chemical interactions. The importance of radiative-chemical interactions within the troposphere and stratosphere has been examined in some detail. We find that increases of radiatively and/or chemically active trace gases such as CO2, CH4 and N2O have both the direct effects and the indirect effects on climate change by changing the atmospheric O3 profile through their interaction with chemical processes in the atmosphere. It is also found that the climatic effect of ozone depends strongly on its vertical distribution throughout the troposphere and stratosphere, as well on its column amount in the atmosphere.

  8. Effects of Strain Rate and Plastic Work on Martensitic Transformation Kinetics of Austenitic Stainless Steel 304

    Institute of Scientific and Technical Information of China (English)

    Fang PENG; Xiang-huai DONG; Kai LIU; Huan-yang XIE

    2015-01-01

    The martensitic transformation behavior and mechanical properties of austenitic stainless steel 304 were studied by both experiments and numerical simulation. Room temperature tensile tests were carried out at various strain rates to investigate the effect on volume fraction of martensite, temperature increase and flow stress. The results show that with increasing strain rate, the local temperature increases, which suppresses the transformation of martensite. To take into account the dependence on strain level, strain rate sensitivity and thermal effects, a kinetic model of martensitic transformation was proposed and constitutive modeling on stress-strain response was conducted. The validity of the proposed model has been proved by comparisons between simulation results and experimental ones.

  9. Martensitic transformations in nanostructured nitinol: Finite element modeling of grain size and distribution effects

    DEFF Research Database (Denmark)

    Liu, Hong-Sheng; Mishnaevsky, Leon

    2013-01-01

    A computational model of martensitic phase transformation in nanostructured nitinol is developed which takes into account the grain size effect. On the basis of the theoretical analysis of the thermodynamic transformation criterion and the energy barrier for phase transformation, it was demonstra......A computational model of martensitic phase transformation in nanostructured nitinol is developed which takes into account the grain size effect. On the basis of the theoretical analysis of the thermodynamic transformation criterion and the energy barrier for phase transformation, it was...... demonstrated that the energy barrier for martensitic phase transformation in nanocrystalline nitinol increase drastically with decreasing the grain size. Finite element simulations of phase transformations and structure evolution in nanocrystalline nitinol under mechanical (tensile) loading are carried out for...... transformation are totally suppressed. Graded and localized distributions of grain sizes of nitinol were compared with nitinol samples with homogeneous grain size distribution. In the materials with localized region of small grains, it was observed that the martensite rich regions form first on the border...

  10. Genome, functional gene annotation, and nuclear transformation of the heterokont oleaginous alga Nannochloropsis oceanica CCMP1779.

    Directory of Open Access Journals (Sweden)

    Astrid Vieler

    Full Text Available Unicellular marine algae have promise for providing sustainable and scalable biofuel feedstocks, although no single species has emerged as a preferred organism. Moreover, adequate molecular and genetic resources prerequisite for the rational engineering of marine algal feedstocks are lacking for most candidate species. Heterokonts of the genus Nannochloropsis naturally have high cellular oil content and are already in use for industrial production of high-value lipid products. First success in applying reverse genetics by targeted gene replacement makes Nannochloropsis oceanica an attractive model to investigate the cell and molecular biology and biochemistry of this fascinating organism group. Here we present the assembly of the 28.7 Mb genome of N. oceanica CCMP1779. RNA sequencing data from nitrogen-replete and nitrogen-depleted growth conditions support a total of 11,973 genes, of which in addition to automatic annotation some were manually inspected to predict the biochemical repertoire for this organism. Among others, more than 100 genes putatively related to lipid metabolism, 114 predicted transcription factors, and 109 transcriptional regulators were annotated. Comparison of the N. oceanica CCMP1779 gene repertoire with the recently published N. gaditana genome identified 2,649 genes likely specific to N. oceanica CCMP1779. Many of these N. oceanica-specific genes have putative orthologs in other species or are supported by transcriptional evidence. However, because similarity-based annotations are limited, functions of most of these species-specific genes remain unknown. Aside from the genome sequence and its analysis, protocols for the transformation of N. oceanica CCMP1779 are provided. The availability of genomic and transcriptomic data for Nannochloropsis oceanica CCMP1779, along with efficient transformation protocols, provides a blueprint for future detailed gene functional analysis and genetic engineering of Nannochloropsis

  11. Transformations of the chemical compositions of high molecular weight DOM along a salinity transect: Using two dimensional correlation spectroscopy and principal component analysis approaches

    Science.gov (United States)

    Abdulla, Hussain A. N.; Minor, Elizabeth C.; Dias, Robert F.; Hatcher, Patrick G.

    2013-10-01

    In a study of chemical transformations of estuarine high-molecular-weight (HMW, >1000 Da) dissolved organic matter (DOM) collected over a period of two years along a transect through the Elizabeth River/Chesapeake Bay system to the coastal Atlantic Ocean off Virginia, USA, δ13C values, N/C ratios, and principal component analysis (PCA) of the solid-state 13C NMR (nuclear magnetic resonance) spectra of HMW-DOM show an abrupt change in both its sources and chemical structural composition occurring around salinity 20. HMW-DOM in the lower salinity region had lighter isotopic values, higher aromatic and lower carbohydrate contents relative to that in the higher salinity region. These changes around a salinity of 20 are possibly due to introduction of a significant amount of new carbon (autotrophic DOM) to the transect. PC-1 loadings plot shows that spatially differing DOM components are similar to previously reported 13C NMR spectra of heteropolysaccharides (HPS) and carboxyl-rich alicyclic molecules (CRAM). Applying two dimensional correlation spectroscopy techniques to 1H NMR spectra from the same samples reveals increases in the contribution of N-acetyl amino sugars, 6-deoxy sugars, and sulfated polysaccharides to HPS components along the salinity transect, which suggests a transition from plant derived carbohydrates to marine produced carbohydrates within the HMW-DOM pool. In contrast to what has been suggested previously, our combined results from 13C NMR, 1H NMR, and FTIR indicate that CRAM consists of at least two different classes of compounds (aliphatic polycarboxyl compounds and lignin-like compounds).

  12. Chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium nitrate solutions

    International Nuclear Information System (INIS)

    These analytical procedures are designed to show whether a given material meets the purchaser's specifications as to plutonium content, effective fissile content, and impurity content. The following procedures are described in detail: plutonium by controlled-potential coulometry; plutonium by amperometric titration with iron(II); free acid by titration in an oxalate solution; free acid by iodate precipitation-potentiometric titration method; uranium by Arsenazo I spectrophotometric method; thorium by thorin spectrophotometric method; iron by 1,10-phenanthroline spectrophotometric method; chloride by thiocyanate spectrophotometric method; fluoride by distillation-spectrophotometric method; sulfate by barium sulfate turbidimetric method; isotopic composition by mass spectrometry; americium-241 by extraction and gamma counting; americium-241 by gamma counting; gamma-emitting fission products, uranium, and thorium by gamma-ray spectroscopy; rare earths by copper spark spectrochemical method; tungsten, niobium (columbium), and tantalum by spectrochemical method; simple preparation by spectrographic analysis for general impurities

  13. Application of noble metal chemical addition technique to nuclear power station

    International Nuclear Information System (INIS)

    The Hamaoka Nuclear Power Station of the Chubu Electric Power Co., Ltd. started to operate its No.1 machine on 1976 and has its operation results for 24 years. In order to operate the plant safely and stably, development of countermeasure technique on stress corrosion cracking (SCC) of nuclear reactor pressure vessel (RPV) and inter-reactor structures and its countermeasure engineering has been carried out. Recently, the noble metal chemical addition (NMCA) technique was developed as an SCC prevention conservation countermeasure in U.S.A., and was already performed some actual operations at actual machines. The NMCA is performed by adding aqueous solution of noble metals (Pt, Rh) into the reactor under keeping 130 plus and minus 10 centigrade in water temperature in the reactor and 0.1 to 0.3 MPa in pressure, after removing power generators and stopping nuclear reactor for its periodical inspection, to keep these conditions for about two days to add micro amount of noble metals onto material surfaces in RPV and inter-reactor structures. Japanese electric power companies are investigating the application of NMCA technique to inland plants. (G.K.)

  14. Simulation of the chemical environment of a nuclear explosion with exploding wires

    International Nuclear Information System (INIS)

    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

  15. Chemical, mass spectrometric, spectrochemical, nuclear and radiochemical analysis of nuclear-grade plutonium metal

    International Nuclear Information System (INIS)

    These analytical procedures are designed to show whether a given material meets the purchaser's specifications as to plutonium content, effective fissile content, and impurity content. The following procedures are described in detail: dissolution procedure; plutonium by controlled-potential coulometry; plutonium by amperometric titration with iron(II); plutonium by ceric sulfate titration method; uranium by Arsenazo I spectrophotometric method; thorium by thorin spectrophotometric method; iron by 1,10-phenanthroline spectrophotometric method; iron by 2,2'-bipyridyl spectrophotometric method; chloride by the thiocyanate spectrophotometric method; fluoride by distillation-spectrophotometric method; nitrogen by distillation-Nessler reagent spectrophotometric method; carbon by the direct combustion-thermal conductivity method; sulfur by distillation-spectrophotometric method; isotopic composition by mass spectrometry; Americium-241 by extraction and gamma counting; Americium-241 by gamma counting; gamma-emitting fission products, uranium, and thorium by gamma-ray spectroscopy; rare earths by copper spark spectrochemical method; tungsten, niobium (columbium) and tantalum by spectrochemical method; sample preparation for spectrographic analysis for trace impurities

  16. Coordination chemistry of the sup 212 Pb/ sup 212 Bi nuclear transformation: Alpha-emitting radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Parks, N.J.; Harris, W.R.; Keen, C.L.; Cooper, S.R.

    1992-07-01

    Subdivisions of this project are: (a) the synthesis of prototypical thiolate and dithiocarbamate based hexacoordinate complexes, (b) radiochemical engineering for generation of no-carrier-added lead and bismuth radioelements, (c) the first isolation of bismuth-binding proteins from in vivo studies with cyclotron produced {sup 205/206}Bi tracer, and (d) initial development of transport mechanisms for the intracellular radiobiological study of alpha emitting bismuth, and (e) the initiation of chemical equilibrium studies and biochemical pathways with cyclotron-produced, no-carrier-added, {sup 203}Pb (T{sub 1/2} = 51 hr).

  17. Coordination chemistry of the 212Pb/212Bi nuclear transformation: Alpha-emitting radiopharmaceuticals

    International Nuclear Information System (INIS)

    Subdivisions of this project are: (a) the synthesis of prototypical thiolate and dithiocarbamate based hexacoordinate complexes, (b) radiochemical engineering for generation of no-carrier-added lead and bismuth radioelements, (c) the first isolation of bismuth-binding proteins from in vivo studies with cyclotron produced 205/206Bi tracer, and (d) initial development of transport mechanisms for the intracellular radiobiological study of alpha emitting bismuth, and (e) the initiation of chemical equilibrium studies and biochemical pathways with cyclotron-produced, no-carrier-added, 203Pb (T1/2 = 51 hr)

  18. Effect of carbonate and phosphate ratios on the transformation of calcium orthophosphates

    International Nuclear Information System (INIS)

    Graphical abstract: Complexes among phosphate, carbonate and calcium have been prepared via a facile hydrothermal route. The synthesized product at the low (0.15) and the high (1.8) molar ratio of PO43−/CO32− is calcium phosphate hydrate and hydroxylapatite (HAp), respectively. Molar ratios of PO43−/CO32− are effective on the reduction of carbonate activity during the crystallization of HAp. - Highlights: • Formation of different complexes from CO32−, PO43− and Ca2+ solutions at 60 °C. • Molar ratios of PO43−/CO32 cause changes in phase and size of synthesized products. • Addition of PO43 inhibited the activity of CO32− during bound with Ca2+. • The phase transformation was completed, when CO32− peaks disappeared in FTIR. • PO43−, CO32− and Ca2+ distributed heterogeneously on the surface of precipitation. - Abstract: Complexes among phosphate, carbonate and calcium have been synthesized by a designed hydrothermal method. Effects of carbonate and phosphate ratios on the transformation of calcium-orthophosphates were investigated. With X-ray diffraction measurement the synthesized product at the low (0.15) and the high (1.8) molar ratio of PO43−/CO32− is calcium phosphate hydrate at pH 9.0, and hydroxylapatite (HAp) at pH 8.0, respectively. Fourier transform infrared spectroscopy of product at the high ratio (1.8) of PO43−/CO32− shows that the CO32− peaks disappear, and the strong peaks at 1412 and 1460 cm−1 are assigned to the vibrations of PO43− in HAp. 31P nuclear magnetic resonance spectra of products at the low (0.15–0.6) to the high (1.2–1.8) ratios of PO43−/CO32− are obtained at 2.9 and 2.7 ppm, respectively. Molar ratios of PO43−/CO32− are effective on the reduction of carbonate activity during the formation and infiltration events of calcium-phosphate surface precipitates, and are subsequently enclosed during HAp formation

  19. Features of adsorbed radioactive chemical elements and their isotopes distribution in iodine air filters AU-1500 at nuclear power plants

    CERN Document Server

    Neklyudov, I M; 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 radioactive chemical elements and their isotopes in the granular filtering medium in the iodine air filters of the type of AU1500 in the forced exhaust ventilation systems at the nuclear power plant. The gamma 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 AU1500 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 AU1500 iodine air filter, which was exposed to the bremsstrahlung gamma quantum irradiation, produced by the accelerating electrons in the tantalum target, are obtained. The spatial distributions of the detected chemical element 127I and some other chemical elements and their isotopes in the layer of absorber, which was made of the cylindrical coal granule...

  20. Effect of Niobium on Isothermal Transformation of Austenite to Ferrite in HSLA Low-Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    CAO Jian-chun; LIU Qing-you; YONG Qi-long; SUN Xin-jun

    2007-01-01

    Using thermomechanical simulation experiment, the kinetics of the isothermal transformation of austenite to ferrite in two HSLA low-carbon steels containing different amounts of niobium was investigated under the conditions of both deformation and undeformation. The results of optical microstructure observation and quantitative metallography analysis showed that the kinetics of the isothermal transformation of austenite to ferrite in lower niobium steel with and without deformation suggests a stage mechanism, wherein there exists a linear relationship between the logarithms of holding time and ferrite volume fraction according to Avrami equation, whereas the isothermal transformation of austenite to ferrite in high niobium steel proceeds via a two stage mechanism according to micrographs, wherein, the nucleation rate of ferrite in the initial stage of transformation is low, and in the second stage,the rate of transformation is high and the transformation of residual austenite to ferrite is rapidly complete. Using carbon extraction replica TEM, niobium carbide precipitation for different holding time was investigated and the results suggested that NbC precipitation and the presence of solute niobium would influence the transformation of austenite to ferrite. The mechanism of the effect of niobium on the isothermal transformation was discussed.

  1. Effect of Nuclear Binding Energy to K Factor

    Institute of Scientific and Technical Information of China (English)

    HOU Zhao-Yu; GUO Ai-Qiang

    2007-01-01

    We modify the square of virtual photon four-momentum by using nuclear binding energy formula,and calculate the effect of nuclear binding energy to K factor and Compton subprocess and annihilate subprocess in A-A collision Drell-Yan process.The outcome indicates that the effect of nuclear binding energy to K factor is obvious in little x region and it would disappear gradually as x increases.

  2. Competencies measured in assessment centers: Predictors of transformational leadership and leader's effectiveness

    OpenAIRE

    Dočekalová Soňa; Vaculík Martin; Procházka Jakub

    2016-01-01

    The objective of this study is to explore which competencies predict leader effectiveness. Based on theory and job analysis, we observed the effects of five leaders' competencies (achievement orientation, problem analysis and problem solving, social sensitivity, influence, and integrity) on three indicators of effectiveness (perceived leader's effectiveness, leadership emergence, and team performance). Furthermore, we examined whether transformational leadership mediates these effects. We col...

  3. Effect of composition and cold work on the ferrite transformation in feroplug materials

    International Nuclear Information System (INIS)

    Feroplug is a newly developed temperature indicator suitable for use in the remaining life assessment of high temperature components in power generating plants. The device has been patented in the US on March 17, 1992 under patent number 5,096,304, by the British Technology Group. The Feroplug uses the phase transformation characteristics of duplex stainless steels for temperature measurement. Duplex stainless steels contain ferrite and austenite. Upon exposure to elevated temperatures, the ferrite transforms into austenite, carbides and intermetallic phases. The transformation can be easily monitored by magnetic measurements using a device called the Feritscope. A number of specially designed duplex stainless steels have been produced and the effects of silicon, carbon, and prior cold work on the phase transformation in these alloys. The ferrite transformation was found to be accelerated by prior cold work and by the addition of silicon. The effect of carbon was complicated. Increase in carbon content resulted in a slight increase in the rate of transformation at the early stage, but at the later stage of the transformation the effect of higher carbon content was to reduce the rate of transformation

  4. Effect of Nb on the transformation behaviour of Nb-Ti microalloyed steels

    International Nuclear Information System (INIS)

    In the thermomechanical processing of niobium microalloyed steels, the strain induced precipitation of Nb(C,N) in austenite impedes the mobility of austenite grain boundaries during recrystallization, leading to the well-known pancaked austenite structure, which is critical to the achievement of the fine ferrite grain size. However, retention of some Nb in solid solution in austenite upon completion rolling is desirable. Solute niobium suppresses the austenite to ferrite transformation, promoting the formation of a bainitic or acicular microstructure, contributing to transformation hardening. As well, solute Nb is available to precipitate in the ferrite/bainite during and subsequent to transformation and thus offers a substantial precipitation strengthening potential. Both factors enhance the strength of steel. A detailed study has been conducted using dilatometry to establish the effect of solute Nb on austenite transformation kinetics. Transformation hardening as indicated by the hardness of the specimen and the microstructure is found to correlate well with the magnitude of undercooling associated with the transformation. While solute niobium and cooling rate increase the undercooling and therefore promote transformation hardening, deformation prior to transformation decreases the undercooling as solute niobium is depleted through precipitation. However, strengthening by precipitation of NbC partly compensates for the loss of transformation hardening through depletion of Nb and C from the matrix during precipitate growth. The effect of solute niobium on transformation hardening is evaluated from laboratory hot rolling trials and the results are used to rationalize the mechanical properties of linepipe alloys (0.04C, 1.60 Mn, 0.07 Nb, and 0.015 Ti) processed in the laboratory and actual mill production runs

  5. EFFECT OF CHEMICAL COMPOSITION ON RETAINED AUSTENITE IN TRIP STEEL

    Institute of Scientific and Technical Information of China (English)

    Y. Chen; X. Chen; Q.F. Wang; G.L. Yuan; C.Y. Li; X.Y. Li; Y.X. Wang

    2002-01-01

    The systematic chemical compositions including common C, Si, Mn, Al, and micro- alloying elements of Ti and Nb were designed for high volume fraction of retained austenite as much as possible. The thermo-cycle experiments were conducted by using Gleeble 2000 thermo-dynamic test machine for finding the appropriate composition. The experimental results showed that chemical composition had a significant effect on retained austenite, and the appropriate compositions were determined for commercial production of TRIP steels.

  6. Modeling of austenite to ferrite transformation

    Indian Academy of Sciences (India)

    Mohsen Kazeminezhad

    2012-06-01

    In this research, an algorithm based on the -state Potts model is presented for modeling the austenite to ferrite transformation. In the algorithm, it is possible to exactly track boundary migration of the phase formed during transformation. In the algorithm, effects of changes in chemical free energy, strain free energy and interfacial energies of austenite–austenite, ferrite–ferrite and austenite–ferrite during transformation are considered. From the algorithm, the kinetics of transformation and mean ferrite grain size for different cooling rates are calculated. It is found that there is a good agreement between the calculated and experimental results.

  7. An aging assessment of transformers in 1E power systems

    International Nuclear Information System (INIS)

    This paper presents the findings of the Idaho National Engineering Laboratory (INEL) Phase 1 study of the effects of age on nuclear power plant Class 1E power transformers, the significance of transformer aging on plant safety, and the capabilities to mitigate the effects of transformer aging to prevent risk significant failures. The following areas were included in the INEL study: The characteristics of Class 1E power transformers used in nuclear power plants were determined. All known transformer stressors were identified, their effect on transformer materials determined, and the effects of these stressors with time assessed. On- and off-line techniques to detect the degradation of all types of transformers were identified and their effectiveness examined. The information provided in reactor operation data bases was evaluated. The capability of various recommendations to mitigate the effects of transformer aging and prevent unexpected transformer failures was evaluated. The risk significance of transformer aging was determined. Conclusions have been made on the effects of aging on transformer performance, the capability to prevent/detect/mitigate aging effects prior to transformer failure, and the effectiveness of current maintenance and monitoring methods

  8. Effects of irrigation efficiency on chemical transport processes

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Irrigation practices greatly affect sustainable agriculture development. In this study, we investigated the effects of irrigation efficiency on water flow and chemical transport in soils, which had significant impact on the environment. Field dye staining experiments were conducted at different soils with various irrigation amount. Image analysis was conducted to study the heterogeneous flow patterns and their relationships with the irrigation efficiency. Irrigation efficiency and its environmental effects were evaluated using various indictors, including application efficiency, deep percolation ratio, storage efficiency, and uniformity. Under the same irrigation condition, soil chemical distributions were more heterogeneous than soil water distributions. The distributions were mainly affected by soil texture, initial soil water content, and irrigation amount. Storage efficiency, irrigation uniformity, and deep percolation ratio increased with irrigation amount. Since the chemical distribution uniformity was lower than the water uniformity, the amount of chemical leaching increased sharply with decrease of irrigation uniformity, which resulted in high environmental risks of groundwater pollution.

  9. Role of effective interaction in nuclear disintegration processes

    CERN Document Server

    Basu, D N

    2003-01-01

    A simple superasymmetric fission model using microscopically calculated nuclear potentials has shown itself to be outstandingly successful in describing highly asymmetric spontaneous disintegration of nuclei into two composite nuclear fragments. The nuclear interaction potentials required to describe these nuclear decay processes have been calculated by double folding the density distribution functions of the two fragments with a realistic effective interaction. The microscopic nucleus-nucleus potential thus obtained, along with the Coulomb interaction potential and the minimum centrifugal barrier required for the spin-parity conservation, has been used successfully for the lifetime calculations of these nuclear disintegration processes.

  10. Prediction of Coupled Thermal, Hydrological and Chemical Processes at the Proposed Yucca Mountain Nuclear Waste Repository: An Integrated Approach

    International Nuclear Information System (INIS)

    An integrated modeling approach was developed to investigate long-term coupled thermal, hydrological, and chemical (THC) processes that could take place around nuclear waste emplacement tunnels (drifts). The approach involves the development of process models, followed by numerical implementation and validation against field and laboratory experiments before conducting long-term predictive simulations. An outcome of this work was the refinement and validation of an existing reactive transport numerical code for applications specific to the geologic storage of nuclear waste. The model was applied to the case of the proposed high-level nuclear waste repository at Yucca Mountain, Nevada, to evaluate the chemistry of waters potentially seeping into drifts and the effect of water-rock interaction on long-term hydrological behavior around the repository. At liquid saturations significantly larger than residual, no extreme pH or salinity values were predicted. Mineral precipitation around drifts consists mainly of silica with minor calcite, trace zeolites and clays. The effect of mineral precipitation on flow depends largely on initial fracture porosity, and results in negligible to significant diversion of percolation around the drift. Further analyses of model uncertainty are under way to improve confidence in model results

  11. The impact of conventional and nuclear industries on the population: A comparative study of the radioactive and chemical aspects

    International Nuclear Information System (INIS)

    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 agricultural and medical activities, as well as exposure to natural radiation, were considered. The methodology developed from this study should be useful for authorities called upon to define economic orientations, industrial development and pollution abatement programmes on a regional scale, by providing an objective view of the hierarchy of risks and their distribution within the population

  12. Research on the transformation of nitrate due to its chemical interaction with metals in TRU waste disposal environment

    International Nuclear Information System (INIS)

    Some TRU wastes contain nitrate ions as salt. The nitrate ions might transform into NO2- and NH3, etc. in the disposal site environment because of reducing agent such as metals, possibly changing disposal site environment or affecting nuclide migration parameters. Therefore, we investigated of chemical interaction between NO3- and metals in a low oxygen environment that corresponds to the disposal site environment. (1) The reaction rate constant between carbon steel and NO3- in an environment with low oxygen and high pH underground water was obtained through electrochemical tests. (2) The long-term data on the products (NH3,H2, etc.) of reaction between metals (carbon steel, stainless steel, zircaloy) and NO3- was obtained through immersion tests in an environment with low oxygen and high pH underground water. According to the long-term data of [NO3-], [NO2-] and [NH3], it was considered that reducing reaction of nitrate was consecutive reaction (NO3- → NO2- → NH3). (3) The decomposition and transition behavior of No3- around disposal facilities evaluated, using the geochemical code (PHREEQM-2D), which have considered geochemical reaction based on experimental results. (author)

  13. The Varying Effects of Uniaxial Compressive Stress on the Bainitic Transformation under Different Austenitization Temperatures

    Directory of Open Access Journals (Sweden)

    Mingxing Zhou

    2016-05-01

    Full Text Available In this study, thermal simulation experiments under different austenitization temperatures and different stress states were conducted. High-temperature laser scanning confocal microscopy (LSCM, thermal dilatometry, and scanning electron microscope (SEM were used to quantitatively investigate the effects of the uniaxial compressive stress on bainitic transformation at 330 °C following different austenitization temperatures. The transformation plasticity was also analyzed. It was found that the promotion degree of stress on bainitic transformation increases with the austenitization temperature due to larger prior austenite grain size as well as stronger promoting effect of mechanical driving force on selected variant growth at higher austenitization temperatures. The grain size and the yield strength of prior austenite are other important factors which influence the promotion degree of stress on bainitic transformation, besides the mechanical driving force provided by the stress. Moreover, the transformation plasticity increases with the austenitization temperature.

  14. Ionospheric Effects of Underground Nuclear Explosions

    Science.gov (United States)

    Park, J.; von Frese, R. R.; G-Brzezinska, D. A.; Morton, Y.

    2010-12-01

    Telemetry from the Russian INTERCOSMOS 24 satellite recorded ELF and VLF electromagnetic disturbances in the outer ionosphere from an underground nuclear explosion that was detonated at Novaya Zemlya Island on 24 October 1994. The IC24 satellite observations were obtained at about 900 km altitude within a few degrees of ground zero. The disturbances were interpreted for magnetohydrodynamic excitation of the ionosphere’s E layer by the acoustic wave. Electrons are accelerated along the magnetic force lines to amplify longitudinal currents and magnetic disturbances that may be measured by magnetometers at ground-based observatories and on-board satellites. The underground nuclear test near P’unggye, North Korea on 25 May 2009 provides a further significant opportunity for studying the utility of ionospheric disturbances for characterizing ground zero. Of the seismic, infrasound, hydroacoustic, and radionuclide detection elements of the International Monitoring System (IMS) established by the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO), only the first two elements detected this event. However, the event also appears to have been recorded as a direct traveling ionospheric disturbance (TID) in the slant total electron content (TEC) observations derived from a network of the Global Navigation Satellite System (GNSS) measurements. The TID was observed to distances of at least 600 km from the explosion site propagating with a speed of about 281m/s. Thus, the global distributions and temporal variations of the TEC, may provide important information to help detect and characterize clandestine underground nuclear explosions.

  15. Quantum Nuclear Extension of Electron Nuclear Dynamics on Folded Effective-Potential Surfaces

    DEFF Research Database (Denmark)

    Hall, B.; Deumens, E.; Ohrn, Y.;

    2014-01-01

    A perennial problem in quantum scattering calculations is accurate theoretical treatment of low energy collisions. We propose a method of extracting a folded, nonadiabatic, effective potential energy surface from electron nuclear dynamics (END) trajectories; we then perform nuclear wave packet dy...... dynamics on that surface and calculate differential cross sections for two-center, one (active) electron systems.......A perennial problem in quantum scattering calculations is accurate theoretical treatment of low energy collisions. We propose a method of extracting a folded, nonadiabatic, effective potential energy surface from electron nuclear dynamics (END) trajectories; we then perform nuclear wave packet...

  16. A micromechanics constitutive model of transformation plasticity with shear and dilatation effect

    Science.gov (United States)

    Sun, Q. P.; Hwang, K. C.; Yu, S. W.

    B ASED on micromechanics, thermodynamics and microscale t → m transformation mechanism considerations a micromechanics constitutive model which takes into account both the dilatation and shear effects of the transformation is proposed to describe the plastic, pseudoelastic and shape memory behaviors of structural ceramics during transformation under different temperatures. In the derivation, a constitutive element (representative material sample) was used which contains many of the transformed m-ZrO 2 grains or precipitates as the second phase inclusions embedded in an elastic matrix. Under some basic assumptions, analytic expressions for the Helmholtz and complementary free energy of the constitutive element are derived in a self-consistent manner by using the Mori-Tanaka method which takes into account the interaction between the transformed inclusions. The derived free energy is a function of externally applied macroscopic stress (or strain), temperature, volume fraction of transformed phase and the averaged stressfree transformation strain (eigenstrain) of all the transformed inclusions in the constitutive element, the latter two quantities being considered to be the internal variables describing the micro-structural rearrangement in the constitutive element. In the framework of the Hill-Rice internal variable constitutive theory, the transformation yield function and incremental stress strain relations, in analogy to the theory of metal plasticity, for proportional and non-proportional loading histories are derived, respectively. The theoretical predictions are compared with the available experimental data of Mg-PSZ and Ce-TZP polycrystalline toughening ceramics.

  17. Thermal Bogoliubov transformation in nuclear structure theory

    OpenAIRE

    Vdovin, A. I.; Dzhioev, Alan A.

    2010-01-01

    Thermal Bogoliubov transformation is an essential ingredient of the thermo field dynamics -- the real time formalism in quantum field and many-body theories at finite temperatures developed by H. Umezawa and coworkers. The approach to study properties of hot nuclei which is based on the extension of the well-known Quasiparticle-Phonon Model to finite temperatures employing the TFD formalism is presented. A distinctive feature of the QPM-TFD combination is a possibility to go beyond the standa...

  18. Two-dimensional electrophoretic analysis of transformation-sensitive polypeptides during chemically, spontaneously, and oncogene-induced transformation of rat liver epithelial cells

    DEFF Research Database (Denmark)

    Wirth, P J; Luo, L D; Fujimoto, Y; Bisgaard, H C

    1992-01-01

    Recently, we described the establishment of a computerized database of rat liver epithelial (RLE) cellular polypeptides (Wirth et al., Electrophoresis, 1991, 12, 931-954). This database has now been expanded to include the analysis of cellular polypeptide alterations during chemically (aflatoxin B1...

  19. 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...

  20. The Effects of Nuclear Terrorism Fizzles

    CERN Document Server

    Liolios, T E

    2002-01-01

    The September 11 terrorist attack against America has caused a lot of concern to the American public and the entire world, which is suspecting a new attack sooner or later. The most frightening scenario is the one involving the detonation of a nuclear device at the heart of a large metropolitan city. Unless the terrorists are in possession of a fully assembled modern nuclear weapons it is very likely that they will possess a crude nuclear device which has been assembled in a terrorist camp by people with relatively limited technological resources. It well known that the Oppenheimer team which designed and tested the first nuclear weapon (the gadget) had a lot of reservations as to whether the first test at Alamogordo would produce any yield at all. Therefore, the most likely scenario is that the terrorists will achieve either a nominal yield or no yield at all (Fizzle). In this study we will investigate all those parameters that play a decisive role in the number of casualties after such an attack so that we ...

  1. Nuclear energy as culture: a practical process for preparation of the agents responsible for that transformation

    International Nuclear Information System (INIS)

    In Brazil research and development are supported mainly by the government, meaning it is public money So it is important to share the knowledge and benefits from the research with the society. Another important question is the scientific analphabetism that raise difficulties for the comprehension of science and technology related matters. One way to improve the understanding process is the creation of workshops for science popularization which presented outstanding results. Participants of a workshop held by the Nuclear Technology Development Center CDTN - BH evaluated with grade 8.8 (from zero to ten) evincing the excellence of the applied model, simple in its essence: a group comprising scientific researchers, journalists and high school teachers attended several specific talks and was asked to prepare material for science divulgation according to the presented criteria. (author)

  2. Effects of biochar application on transformation and chemical forms of C,N and P in soils with different pH%生物质炭对不同 pH 土壤中碳氮磷的转化与形态的影响

    Institute of Scientific and Technical Information of China (English)

    徐秋桐; 邱志腾; 章明奎

    2014-01-01

    clay content,rainfall,and temperature regimes.In recent years,there has been considerable interest in the use of biochar from pyrolysis of renewable biomass to sequester C and improve soil productivity.Much of the stimulus for this interest comes from research on the soils of the Amazon basin,known as Terra Preta de Indio,that contain variable quantities of organic black carbon considered to be of anthropogenic origin.Biochar can improve nutrient availability,cation exchange capacity,bulk density,and water-holding capacity,but these effects depend on the feedstock,prolysis conditions. It is important to evaluate the effects of biochar on soil fertility under different soil and climatic regimes to increase our understanding of potential interactions before widespread use of biochar in agricultural systems.Although biochar has been shown to increase soil fertility and productivity in the tropics,there is limited information about influences of biochar on transformation and chemical forms of C,N and P in soils.Therefore,an incubation experiment was conducted to study the effects of biochar application on transformation and chemical forms of C,N and P in soils with different pH. The experiment included four treatments,i.e.,control without application of any chemical fertilizers and biochar, conventional fertilization with application of chemical fertilizers,biochar treatment with application of biochar but without any chemical fertilizers,and conventional fertilization + biochar treatment with application of both biochar and chemical fertilizers.The treated soils were incubated at temperature of 20 35 ℃ for 12 months,and the incubated soils were characterized for different forms of C,N,and P and potential capacities of N leaching and volatilization loss. The results showed that application of biochar increased soil pH,particularly for acidic soil.Application of biochar increased significantly the accumulation of organic C,microbial biomass C and humic/fulvic acids(H/F)of

  3. Effects of biochar application on transformation and chemical forms of C,N and P in soils with different pH%生物质炭对不同 pH 土壤中碳氮磷的转化与形态的影响

    Institute of Scientific and Technical Information of China (English)

    徐秋桐; 邱志腾; 章明奎

    2014-01-01

    Summary Soil organic matter has an important role in soil fertility and agricultural productivity.Many practices have been used to increase organic carbon in soil,particularly nitrogen fertilization,zero-tillage agriculture,and the addition of large amounts of manure to soil.These practices do not sequester significant quantities of C into soil because most of the organic matter is not stable and is mineralized very fast.Many factors contribute to soil organic C stabilization,including soil clay content,rainfall,and temperature regimes.In recent years,there has been considerable interest in the use of biochar from pyrolysis of renewable biomass to sequester C and improve soil productivity.Much of the stimulus for this interest comes from research on the soils of the Amazon basin,known as Terra Preta de Indio,that contain variable quantities of organic black carbon considered to be of anthropogenic origin.Biochar can improve nutrient availability,cation exchange capacity,bulk density,and water-holding capacity,but these effects depend on the feedstock,prolysis conditions. It is important to evaluate the effects of biochar on soil fertility under different soil and climatic regimes to increase our understanding of potential interactions before widespread use of biochar in agricultural systems.Although biochar has been shown to increase soil fertility and productivity in the tropics,there is limited information about influences of biochar on transformation and chemical forms of C,N and P in soils.Therefore,an incubation experiment was conducted to study the effects of biochar application on transformation and chemical forms of C,N and P in soils with different pH. The experiment included four treatments,i.e.,control without application of any chemical fertilizers and biochar, conventional fertilization with application of chemical fertilizers,biochar treatment with application of biochar but without any chemical fertilizers,and conventional fertilization + biochar

  4. Chemical analysis by nuclear techniques

    International Nuclear Information System (INIS)

    This state art report consists of four parts, production of micro-particles, analysis of boron, alpha tracking method and development of neutron induced prompt gamma ray spectroscopy (NIPS) system. The various methods for the production of micro-paticles such as mechanical method, electrolysis method, chemical method, spray method were described in the first part. The second part contains sample treatment, separation and concentration, analytical method, and application of boron analysis. The third part contains characteristics of alpha track, track dectectors, pretreatment of sample, neutron irradiation, etching conditions for various detectors, observation of track on the detector, etc. The last part contains basic theory, neutron source, collimator, neutron shields, calibration of NIPS, and application of NIPS system

  5. Effect of silicon and prior deformation of austenite on isothermal transformation in low carbon steels

    Institute of Scientific and Technical Information of China (English)

    Minghui CAI; Hun DING; Jiansu ZHANG; Long LI

    2009-01-01

    Isothermal transformation (TTT) behavior of the low carbon steels with two Si con-tents (0.50 wt pct and 1.35 wt pct) was investigated with and without the prior deformation. The results show that Si and the prior deformation of the austenite have significant effects on the transformation of the ferrite and bainite. The addition of Si refines the ferrite grains, accelerates the polygonal ferrite transformation and the formation of M/A constituents, leading to the improvement of the strength. The ferrite grains formed under the prior deformation of the austenite become more ho-mogeneous and refined. However, the influence of deformation on the tensile strength of both steels is dependent on the isothermal temperatures. Thermodynamic calcu-lation indicates that Si and prior deformation reduce the incubation time of both ferrite and bainite transformation, but the effect is weakened by the decrease of the isothermal temperatures.

  6. Fieldable Fourier Transform Spectrometer: System Construction, Background Variability Measurements, and Chemical Attack Warning Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hatchell, Brian K.; Harper, Warren W.; Batishko, Charles R.; Johnson, Timothy J.; Sheen, David M.; Stewart, Timothy L.; Schultz, John F.

    2002-10-01

    The infrared sensors task at the Pacific Northwest National Laboratory (PNNL) is focused on the science and technology of remote and in-situ chemical sensors for detecting proliferation and countering terrorism. Missions to be addressed by remote chemical sensor development will include detecting proliferation of nuclear or chemical weapons, and providing warning of terrorist use of chemical weapons. Missions to be addressed by in-situ chemical sensor development include countering terrorism by screening luggage, personnel, and shipping containers for explosives, firearms, narcotics, chemical weapons, or chemical weapons residues, and mapping contaminated areas. The science and technology relevant to these primary missions is also likely to be useful for battlefield chemical weapons defense, air operations support, monitoring emissions from chemical weapons destruction facilities or industrial chemical plants, and law enforcement applications. PNNL will seek to serve organizations with direct interest in these missions through collaborative research and development efforts approved by NA-22. During FY02, PNNL began assembling a remote IR detection capability that would allow field experiments to be conducted. The capability consists of a commercially available FTIR (Fourier Transform Infrared) emission spectrometer and a frequency-modulation differential-absorption LIDAR (FM-DIAL) system being developed at PNNL. To provide environmental protection for these systems, a large, well insulated, temperature controlled trailer was specified and procured. While the FTIR system was field-ready, the FM-DIAL system required many modifications to prepare for field deployment. This document provides an overview of the FTIR system, summarizes the modifications made to the FM-DIAL system, and describes the salient features of the remote systems trailer.

  7. Use of Ionic Liquid as Green Catalyst, Reagent as Well as Reaction Medium in Chemical Transformations

    Institute of Scientific and Technical Information of China (English)

    Brindaban C. Ranu

    2005-01-01

    @@ 1Introduction The toxic and volatile nature of many organic solvents, particularly chlorinated hydrocarbons that are widely used in organic synthesis have posed a serious threat to the environment. Thus, design of organic solvent - free reaction and use of alternative green solvents like water, supercritical fluids, and ionic liquids have received tremendous attention in recent times in the area of green synthesis. The ionic liquids have been the subject of considerable current interest as environmentally benign reaction media in organic synthesis because of their unique properties of nonvolatility, noninf1ammability, and recyclability among others and during last few years ionic liquids have been successfully employed as green solvents for a variety of important reactions.However, the ability of ionic liquid as a clean catalyst and reagent has not been explored to any great extent although it is of much importance in the context of green synthesis.

  8. Defining the Effects of Transformational Leadership on Organisational Learning: A Cross-Cultural Comparison.

    Science.gov (United States)

    Lam, Y. L. Jack

    2002-01-01

    Cross-cultural analysis of the effects of transformational leadership on organizational learning in elementary and secondary schools in Hong Kong, Western Australia, Canada (Manitoba), and Taiwan. (Contains 41 references.) (PKP)

  9. Current status of medical training for facing chemical, biological and nuclear disasters

    International Nuclear Information System (INIS)

    A descriptive, longitudinal and prospective study was conducted in 200 sixth year-medical students from the Faculty 2 of Medical University in Santiago de Cuba during 2011-2012, with the purpose of determining some of deficiencies affecting their performance during chemical, biological or nuclear disasters, for which an unstructured survey and an observation guide were applied. In the series demotivation of some students regarding the topic, poor theoretical knowledge of the topic, the ignorance of ways to access information and the little use of this topic in college scientific events were evidenced, which also involved the little systematization of the content on disasters and affected the objectives of medical training with comprehensive profile

  10. 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

  11. Effects of Predeformation on the Reverse Martensitic Transformation of TiNi Shape Memory Alloy

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    DSC was used to study the effects of predeformation on the reverse martensitic transformation of near-equiatomic TiNi alloy. Both the start temperature As and the finish temperature Af of the reverse transformation increased with increasing degree of predeformation, but the algebraic difference between As and Ar decreased with increasing predeformation until it reached a minimum value, then remained unchanged with further deformation. Transformation heat also increased with increasing predeformation until it reached a maximum value, then decreased with further predeformation. All the phenomena above were considered to be closely related with he release of elastic strain energy during predeformation.

  12. Nuclear medium effects in $\

    CERN Document Server

    Haider, H; Athar, M Sajjad; Vacas, M J Vicente

    2011-01-01

    We study the nuclear medium effects in the weak structure functions $F_2(x,Q^2)$ and $F_3(x,Q^2)$ in the deep inelastic neutrino/antineutrino reactions in nuclei. We use a theoretical model for the nuclear spectral functions which incorporates the conventional nuclear effects, such as Fermi motion, binding and nucleon correlations. We also consider the pion and rho meson cloud contributions calculated from a microscopic model for meson-nucleus self-energies. The calculations have been performed using relativistic nuclear spectral functions which include nucleon correlations. Our results are compared with the experimental data of NuTeV and CDHSW.

  13. Development and Evaluation of Model Algorithms to Account for Chemical Transformation in the Nearroad Environment

    Science.gov (United States)

    We describe the development and evaluation of two new model algorithms for NOx chemistry in the R-LINE near-road dispersion model for traffic sources. With increased urbanization, there is increased mobility leading to higher amount of traffic related activity on a global scale. ...

  14. Economic effect of applied nuclear-agricultural science in China

    International Nuclear Information System (INIS)

    The economic effect of applied nuclear-agricultural science for 40 years in China have been summarized, analyzed and appraised. The economic regularity and features which are followed by research-development-production in the field of applied nuclear agricultural science in China are explored according to the essential characteristics of economics for input-output ratio and the itself-features of nuclear agricultural science. Some propositions for promoting the development and the economic effect of the applied nuclear-agricultural science in China are also given

  15. Analysis of radicals, radical precursors and chemical transformations for Houston/Texas

    Science.gov (United States)

    Rappenglück, Bernhard; Czader, Beata; Li, Xiangshang

    2015-04-01

    Air quality simulations were performed for the Houston-Galveston-Brazoria area for springtime conditions in May and June of 2009. Meteorological parameters predicted by Weather Research and Forecasting (WRF) model, for which data assimilation with recursive objective analysis was performed, are well simulated most of the time. The Community Multiscale Air Quality (CMAQ) model driven by meteorology from WRF simulates ozone and many other trace species, including radical precursors such as HCHO and HONO, with a satisfactory agreement with observations. While CMAQ satisfactorily captures the daily variations of the OH radical, it sometimes underestimates its high daytime values. Concentrations of HO2 are often underpredicted in polluted air masses and persistently severely underpredicted at low NOx conditions, when the Houston air is affected bymarine air masses. In contrast, concentrations of H2O2 and CH3OOHare almost always overpredicted by the model, the overprediction occurs frequently in the polluted air and occurs always when marine air is encountered. Those mispredictions are consistent despite day-to-day variations in meteorological conditions and emissions and bring into question current representation of radical-related chemistry in the model as radical production and recirculation in the model is overtaken by termination processes and creation ofmore stable compounds, such asH2O2 and CH3OOH. Smaller model biases of H2O2 and peroxides are associated with lower humidity. The relative importance of various photolysis processes as radical sources in the Houston atmosphere was also elucidated. Morning HOx formation is dominated by HONO while ozone contributes the most during midday. HONO contribution to HOx formation is more pronounced at the surface layer where most of it is formed, radical production from ozone is more important at elevated levels where higher concentrations of ozone are observed. Formaldehyde contributes up to 40% and also peaks during midday

  16. EFFECTS OF INTERSTITIAL IMPURITIES ON PHASE TRANSFORMATION OF Ti-Al ALLOYS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    According to the Average Lattice and Atom Models of the Empirical Electron Theory of Solids and Molecules(EET), effects of interstitial impurities on valence electron structures and phase transformation of Ti-Al alloys are analyzed, and descendant degree of bond energy, melting point and liquidus temperatures affected by interstitial impurities are calculated by the bond energy formula of the EET, and then the main experimental results which are not confirmed about phase transformation in Ti-Al alloys are explained.The results are that, because of the effects of interstitial impurities, atom states increase, bond structures are seriously anisotropic, β→α transformation is hindered, and the phase transformation in an intermediate content is very complex. Also, the melting point and liquidus temperatures decrease, and average decreased degree is estimated through approximation by the EET.

  17. Parameter-free determination of actual temperature at chemical freeze-out in nuclear interactions

    International Nuclear Information System (INIS)

    We propose a method to determine the actual temperature at chemical freeze-out in relativistic nucleus-nucleus collisions, using the experimental μq/T and μs/T values, obtained from strange particle ratios. We employ the Hadron Gas formalism, assuming only local thermal equilibration, to relate the quarkchemical potential and temperature. This relation constrains the allowed values of μq/T, μs/T and T, enabling the determination of the actual temperature. Comparison of the inverse slope parameter of the mT-distributions with the actual temperature determines the transverse flow velocity of the fireball matter. Knowledge of these quantities is essential in determining the EoS of nuclear matter and in evaluating interactions with regard to a possible phase transition to QGP. copyright 1995 American Institute of Physics

  18. Effects of Solute Nb Atoms and Nb Precipitates on Isothermal Transformation Kinetics from Austenite to Ferrite

    Science.gov (United States)

    Wang, Li; Parker, Sally; Rose, Andrew; West, Geoff; Thomson, Rachel

    2016-05-01

    Nb is a very important micro-alloying element in low-carbon steels, for grain size refinement and precipitation strengthening, and even a low content of Nb can result in a significant effect on phase transformation kinetics from austenite to ferrite. Solute Nb atoms and Nb precipitates may have different effects on transformation behaviors, and these effects have not yet been fully characterized. This paper examines in detail the effects of solute Nb atoms and Nb precipitates on isothermal transformation kinetics from austenite to ferrite. The mechanisms of the effects have been analyzed using various microscopy techniques. Many solute Nb atoms were found to be segregated at the austenite/ferrite interface and apply a solute drag effect. It has been found that solute Nb atoms have a retardation effect on ferrite nucleation rate and ferrite grain growth rate. The particle pinning effect caused by Nb precipitates is much weaker than the solute drag effect.

  19. Research on Effect Evaluation of Flue Gas Desulfurization Transformation for Coal-fired Power Plants

    OpenAIRE

    Wei Li

    2013-01-01

    With the rapid development of economy, the sulfur dioxide produced in coal has increased dramatically. Flue gas desulfurization is an effective measure to control the sulfur dioxide emissions. Taking Handan thermal power plant as example, this paper evaluates the effectiveness of flue gas desulfurization transformation using the fuzzy comprehensive evaluation method, which may contribute to the implementation of the transformation of outdated flue gas desulfurization.

  20. Effect of coupling transformer on the performance of microwave ion source: simulation and experiment

    International Nuclear Information System (INIS)

    A 2.45 GHz high current microwave ion source is currently operational at VECC. It is able to produce more than 12 mA of beam current with just 300 watts of microwave power. The extracted beam current from the ion source depends strongly on the microwave coupling transformer. In order to understand the effect of microwave coupling on the performance of ion source, we have designed three different types of coupling transformers using ANSYS HFSS code, namely WR-284 waveguide and two double ridged waveguides one with 24 mm ridge width and another with 48 mm ridge width. We have fabricated these transformers and studied experimentally their effect on the extracted current from the ion source. This paper presents simulation details and experimental results of different microwave coupling transformers on performance of the ion source. (author)

  1. Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of uranium hexafluoride

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 These test methods cover procedures for subsampling and for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of uranium hexafluoride UF6. Most of these test methods are in routine use to determine conformance to UF6 specifications in the Enrichment and Conversion Facilities. 1.2 The analytical procedures in this document appear in the following order: Note 1—Subcommittee C26.05 will confer with C26.02 concerning the renumbered section in Test Methods C761 to determine how concerns with renumbering these sections, as analytical methods are replaced with stand-alone analytical methods, are best addressed in subsequent publications. Sections Subsampling of Uranium Hexafluoride 7 - 10 Gravimetric Determination of Uranium 11 - 19 Titrimetric Determination of Uranium 20 Preparation of High-Purity U3O 8 21 Isotopic Analysis 22 Isotopic Analysis by Double-Standard Mass-Spectrometer Method 23 - 29 Determination of Hydrocarbons, Chlorocarbons, and Partially Substitut...

  2. Effective economics of nuclear fuel power complex

    International Nuclear Information System (INIS)

    Problems of the economic theory and practice of functioning the nuclear fuel power complex (NFPC) are considered. Using the principle of market equilibrium for optimization of the NFPC hierarchical system is analyzed. The main attention is paid to determining the prices of production and consumption of the NFPC enterprises. Economic approaches on the optimal calculations are described. The ecological safety of NPP and NFPC enterprises is analyzed. A conception of the market socialism is presented

  3. Chemical transformations of poly[methyl(phenyl)silylene] under weatherometer exposure

    Czech Academy of Sciences Publication Activity Database

    Meszároš, Oto; Schmidt, Pavel; Pospíšil, Jan; Nešpůrek, Stanislav

    Karlsruhe: Gesellschaft für Umweltsimulation, 2004, s. 423-433. ISBN 3-9808382-5-0. [European Weathering Symposium on Natural and Artificial Ageing of Polymers /1./. Prague (CZ), 25.09.2004-26.09.2004] R&D Projects: GA ČR GA202/01/0518; GA MŠk ME 543 Institutional research plan: CEZ:AV0Z4050913 Keywords : poly[methyl(phenyl)silylene] * photochemical stability Subject RIV: CD - Macromolecular Chemistry

  4. Switchgear, transformers, distribution systems for power supply to the safety system of nuclear power plants. KTA safety code, version 6/99

    International Nuclear Information System (INIS)

    This KTA safety code is applicable to switchgear, transformers and distribution systems for power supply to the safety systems of stationary nuclear power plants. The scope of application of the superior requirements according to section 3 of this safety code extends to and includes the power circuit brakers of the electric mains. The scope of application of the component-specific requirements regarding design and inspection of switchgear, transformers and distribution systems according to sections 4 and 5 of this safety code extends to and includes the primary voltage clamps of the transformers of the mains. (orig./CB)

  5. Health effects assessment of chemical exposures: ARIES methodology

    International Nuclear Information System (INIS)

    In this work, we present ARIES* update: a system designed in order to facilitate the human health effects assessment produced by accidental release of toxic chemicals. The first version of ARIES was developed in relation to 82/501/EEC Directive about mayor accidents in the chemical industry. So, the first aim was the support of the effects assessment derived for the chemicals included into this directive. From this establishment, it was considered acute exposures for high concentrations. In this report, we present the actual methodology for considering other type of exposures, such as environmental and occupational. Likewise other versions, the methodology comprises two approaches: quantitative and qualitative assessments. Quantitative assessment incorporates the mathematical algorithms useful to evaluate the effects produced by the most important routes of exposure: inhalation, ingestion, eye contact and skin absorption, in a short, medium and long term. It has been included models that realizes an accurate quantification of doses, effects,... and so on, such as simple approaches when the available information is not enough. Qualitative assessment, designed in order to complement or replace the previous one, is incorporated into an informatics system, developed in Clipper. It executes and displays outstanding and important toxicological information of about 100 chemicals. This information comes from ECDIN (Environmental Chemicals Data and Information Network) database through a collaboration with JRC-ISPRA working group. (Author) 24 refs

  6. Health effects assessment of chemical exposures: ARIES methodology

    Energy Technology Data Exchange (ETDEWEB)

    Sierra, L; Montero, M.; Rabago, I.; Vidania, R.

    1995-07-01

    In this work, we present ARIES* update: a system designed in order to facilitate the human health effects assessment produced by accidental release of toxic chemicals. The first version of ARIES was developed in relation to 82/501/EEC Directive about mayor accidents in the chemical industry. So, the first aim was the support of the effects assessment derived for the chemicals included into this directive. From this establishment, it was considered acute exposures for high concentrations. In this report, we present the actual methodology for considering other type of exposures, such as environmental and occupational. Likewise other versions, the methodology comprises two approaches: quantitative and qualitative assessments. Quantitative assessment incorporates the mathematical algorithms useful to evaluate the effects produced by the most important routes of exposure: inhalation, ingestion, eye contact and skin absorption, in a short, medium and long term. It has been included models that realizes an accurate quantification of doses, effects,... and so on, such as simple approaches when the available information is not enough. Qualitative assessment, designed in order to complement or replace the previous one, is incorporated into an informatics system, developed in Clipper. It executes and displays outstanding and important toxicological information of about 100 chemicals. This information comes from ECDIN (Environmental Chemicals Data and Information Network) database through a collaboration with JRC-ISPRA working group. (Author) 24 refs.

  7. Fourier transform infrared photoacoustic spectroscopy as a potential tool in assessing the role of diet in cuticular chemical composition of Ectatomma brunneum.

    Science.gov (United States)

    Bernardi, R C; Firmino, E L B; Pereira, M C; Andrade, L H C; Cardoso, C A L; Súarez, Y R; Antonialli-Junior, W F; Lima, S M

    2014-01-01

    The cuticular chemical composition plays a significant role in the recognition of nest mates in social insects, thus functioning as a chemical signature of the colony. The structure of cuticular chemicals is subject to interference from genetic and exogenous factors, including diet. In this study, various colonies of the Ectatomma brunneum ant were removed from their natural environment and housed in a laboratory to monitor the response of the cuticular chemical composition to dietary changes. Analyses were performed using gas chromatography and Fourier transform infrared photoacoustic spectroscopy, which has not been previously used for this type of analysis. The results indicate that this method is useful for analyzing biological and natural systems. We observed changes in the chemical signature with food traces in the first 30 days under feed control. Therefore, genetic information may not be the only criterion that can be used to describe the chemical signature of a species; environmental variations also influence recognition signals. Furthermore, these results reinforce the reliability of the Fourier transform infrared photoacoustic spectroscopy method. PMID:25501215

  8. Review of radiation effects in solid-nuclear-waste forms

    International Nuclear Information System (INIS)

    Radiation effects on the stability of high-level nuclear waste (HLW) forms are an important consideration in the development of technology to immobilize high-level radioactive waste because such effects may significantly affect the containment of the radioactive waste. Since the required containment times are long (103 to 106 years), an understanding of the long-term cumulative effects of radiation damage on the waste forms is essential. Radiation damage of nuclear waste forms can result in changes in volume, leach rate, stored energy, structure/microstructure, and mechanical properties. Any one or combination of these changes might significantly affect the long-term stability of the nuclear waste forms. This report defines the general radiation damage problem in nuclear waste forms, describes the simulation techniques currently available for accelerated testing of nuclear waste forms, and reviews the available data on radiation effects in both glass and ceramic (primarily crystalline) waste forms. 76 references

  9. Review of radiation effects in solid-nuclear-waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Weber, W.J.

    1981-09-01

    Radiation effects on the stability of high-level nuclear waste (HLW) forms are an important consideration in the development of technology to immobilize high-level radioactive waste because such effects may significantly affect the containment of the radioactive waste. Since the required containment times are long (10/sup 3/ to 10/sup 6/ years), an understanding of the long-term cumulative effects of radiation damage on the waste forms is essential. Radiation damage of nuclear waste forms can result in changes in volume, leach rate, stored energy, structure/microstructure, and mechanical properties. Any one or combination of these changes might significantly affect the long-term stability of the nuclear waste forms. This report defines the general radiation damage problem in nuclear waste forms, describes the simulation techniques currently available for accelerated testing of nuclear waste forms, and reviews the available data on radiation effects in both glass and ceramic (primarily crystalline) waste forms. 76 references.

  10. Relations of FMmlet Transform to Some Integral Transforms

    Institute of Scientific and Technical Information of China (English)

    ZOUHongxing; DAIQionghai; WANGDianjun; LIYanda

    2004-01-01

    In this paper, we explore the relationships between FMmlet transform and some of the existing integral transforms, namely, the chirplet transform, dispersion transform, wavelet transform, chirp-Fourier transform, Short-time fourier transform (STFT), Gabor transform, Fourier transform, cosine transform, sine transform,Hartley transform, Laplace transform, z-transform, Mellintransform, Hilbert transform, autocorrelation function,cross-correlation function, energy, and the mean value.It is shown that all of these transforms are subspaces of FMmlet transform with specific parameters.

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

    Directory of Open Access Journals (Sweden)

    A. Stenke

    2013-05-01

    Full Text Available 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 different family of CCMs than previously used, to investigate the consequences of such a hypothetical nuclear conflict. In accordance with previous studies, the present work assumes a scenario of a nuclear conflict between India and Pakistan, each applying 50 warheads with an individual blasting power of 15 kt ("Hiroshima size" against the major population centers, resulting in the emission of tiny soot particles, which are generated in the firestorms expected in the aftermath of the detonations. Substantial uncertainties related to the calculation of likely soot emissions, particularly concerning assumptions of target fuel loading and targeting of weapons, have been addressed by simulating several scenarios, with soot emissions ranging from 1 to 12 Tg. Their high absorptivity with respect to solar radiation leads to a tremendous self-lofting of the soot particles into the strato- and mesosphere, where they remain for several years. Consequently, the model suggests Earth's surface temperatures to drop by several degrees Celsius due to the shielding of solar irradiance by the soot, indicating a major global cooling. In addition, there is a substantial reduction of precipitation lasting 5 to 10 yr after the conflict, depending on the magnitude of the initial soot release. Extreme cold spells associated with massive sea ice formation are found during Northern Hemisphere winter, which expose the continental land masses of Northern America and Eurasia to chilling

  12. Effect of nuclear motion on the critical nuclear charge for two-electron atoms

    OpenAIRE

    King, Andrew W; Rhodes, Luke C; Readman, Charles A; Cox, Hazel

    2015-01-01

    A variational method for calculating the critical nuclear charge, Zc, required for the binding of a nucleus to two electrons is reported. The method is very effective and performs well compared to the traditional variational principle for calculating energy. The critical nuclear charge, which corresponds to the minimum charge required for the atomic system to have at least one bound state, has been calculated for helium-like systems both with infinite and finite nuclear masses. The value of $...

  13. Effect of metabolic transformation of monoterpenes on antimutagenic potential in bacterial tests

    OpenAIRE

    Stajković-Srbinović Olivera; Vuković-Gačić Branka; Knežević-Vukčević Jelena; Nikolić Biljana; Mitić-Ćulafić Dragana

    2012-01-01

    The effect of metabolic transformation of the monoterpenes Linalool (Lin), Myrcene (Myr) and Eucalyptol (Euc) was evaluated on their antimutagenic potential against t-butyl hydroperoxide (t-BOOH) and 2-nitropropane (2NP) in E. coli WP2 and in S. typhimurium reversion assays, respectively. Spontaneous mutagenesis was also monitored in both assays. Mammalian metabolic transformation was provided by rat liver microsomes (S9 fraction). None of the monoterpenes was mutagenic, either with or ...

  14. Effects of chemical dispersants on oil physical properties and dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Khelifa, A.; Fingas, M.; Hollebone, B.P.; Brown, C.E. [Environment Canada, Ottawa, ON (Canada). ; Pjontek, D. [Ottawa Univ., ON (Canada). Dept. of Chemical Engineering

    2007-07-01

    Laboratory and field testing have shown that the dispersion of oil spilled in water is influenced by chemical dispersants via the modification of the interfacial properties of the oil, such as oil-brine interfacial tension (IFT). This study focused on new laboratory experiments that measured the effects on the physical properties and dispersion of oil, with particular reference to the effects of chemical dispersants on IFT and oil viscosity and the subsequent effects on oil droplet formation. Experiments were conducted at 15 degrees C using Arabian Medium, Alaska North Slope and South Louisiana crude and Corexit 9500 and Corexit 9527 chemical dispersants. The dispersants were denser than the 3 oils. The effect of IFT reduction on oil dispersion was measured and showed substantial reduction in the size and enhancement of the concentration of oil droplets in the water column. It was shown that the brine-oil IFT associated with the 3 crudes reduced to less than 3.6 mN/m with the application of the chemical dispersants, even at a low dispersant-to-oil ratio (DOR) value of 1:200. The use of chemical dispersants increased the viscosity of the dispersant-oil mixture up to 40 per cent over the neat crude oil. It was shown that for each mixing condition, an optimum value of DOR exists that provides for maximal dispersant effectiveness. The IFT reaches maximum reduction at optimum DOR. It was suggested that oil spill modelling can be improved with further study of IFT reduction with DOR and variations of critical micelle concentration with the type and solubility of chemical dispersant, oil type and oil to water ratio. 13 refs., 3 tabs., 7 figs.

  15. Pollution of the Marine Environment by Dumping: Legal Framework Applicable to Dumped Chemical Weapons and Nuclear Waste in the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Lott, Alexander

    2015-06-01

    Full Text Available The Arctic seas are the world’s biggest dumping ground for sea-disposed nuclear waste and have served among the primary disposal sites for chemical warfare agents. Despite of scientific uncertainty, the Arctic Council has noted that this hazardous waste still affects adversely the Arctic marine environment and may have implications to the health of the Arctic people. The purpose of this manuscript is to establish the rights and obligations of the Arctic States in connection with sea-dumped chemical weapons and nuclear material under international law of the sea, international environmental law and disarmament law. Such mapping is important for considering options to tackle the pollution to the Arctic ecosystems and because there seems to be yet no such analysis across the legal fields carried out. This paper aims first at identifying the scale and approximate locations of sea-disposed nuclear waste and chemical weapons in the Arctic Ocean. The analysis will further focus on ascertaining the possibilities to minimize their adverse effects on the Arctic marine environment under the applicable legal framework. It will be argued in this manuscript that due to the corrosion of the chemical weapons and nuclear material containers, recovering, rather than confining this hazardous waste might be counterproductive as it might cause a sudden and widespread release of chemical agents or radionuclides when surfacing. In this regard, carrying out an environmental impact assessment prior to each such remediation operation would be necessary to determine the most suitable technique for minimizing or eliminating pollution.

  16. Pollution of the Marine Environment by Dumping: Legal Framework Applicable to Dumped Chemical Weapons and Nuclear Waste in the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Lott, Alexander

    2016-06-01

    Full Text Available The Arctic seas are the world’s biggest dumping ground for sea-disposed nuclear waste and have served among the primary disposal sites for chemical warfare agents. Despite of scientific uncertainty, the Arctic Council has noted that this hazardous waste still affects adversely the Arctic marine environment and may have implications to the health of the Arctic people. The purpose of this manuscript is to