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Sample records for solution irradiation method

  1. Solute segregation during irradiation

    International Nuclear Information System (INIS)

    Wiedersich, H.; Okamoto, P.R.; Lam, N.Q.

    1977-01-01

    Irradiation at elevated temperature induces redistribution of the elements in alloys on a microstructural level. This phenomenon is caused by differences in the coupling of the various alloy constituents to the radiation-induced defect fluxes. A simple model of the segregation process based on coupled reaction-rate and diffusion equations is discussed. The model gives a good description of the experimentally observed consequences of radiation-induced segregation, including enrichment or depletion of solute elements near defect sinks such as surfaces, voids and dislocations; precipitation of second phases in solid solutions; precipitate redistribution in two-phase alloys; and effects of defect-production rates on void-swelling rates in alloys with minor solute additions

  2. Studies of short-lived radicals in the. gamma. -irradiated aqueous solution of uridine-5'-monophosphate by the spin-trapping method and the liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Kominami, S [Hiroshima Univ. (Japan); Rokushika, S; Hatano, H

    1976-12-01

    An aerated aqueous solution of uridine-5'-monophosphate was ..gamma..-irradiated with 2-methyl-2-nitrosopropane as a spin-trapping reagent. Liquid chromatography was applied to separate the stable nitroxide radicals in the irradiated solution. The radicals were detected by U.V. and e.s.r. spectrometry. The e.s.r. detection showed four peaks in the chromatogram. The orcinol method for detection of the residual sugar moieties was applied before and after reduction of the base to determine the existence of the 5,6-double bond for the molecules in each fraction. From the combined results of the e.s.r. and orcinol methods, the short-lived radicals which were trapped by 2-methyl-2-nitrosopropane were identified as radicals of N-1 and C-6 positions of the base moiety and t-butyl radicals which was the radiolytic product of the trapping reagent.

  3. Detection methods for irradiated foods

    International Nuclear Information System (INIS)

    Dyakova, A.; Tsvetkova, E.; Nikolova, R.

    2005-01-01

    In connection with the ongoing world application of irradiation as a technology in Food industry for increasing food safety, it became a need for methods of identification of irradiation. It was required to control international trade of irradiated foods, because of the certain that legally imposed food laws are not violated; supervise correct labeling; avoid multiple irradiation. Physical, chemical and biological methods for detection of irradiated foods as well principle that are based, are introducing in this summary

  4. Spices, irradiation and detection methods

    International Nuclear Information System (INIS)

    Sjoeberg, A.M.; Manninen, M.

    1991-01-01

    This paper is about microbiological aspects of spices and microbiological methods to detect irradiated food. The proposed method is a combination of the Direct Epifluorescence Filter Technique (DEFT) and the Aerobic Plate Count (APC). The evidence for irradiation of spices is based on the demonstration of a higher DEFT count than the APC. The principle was first tested in our earlier investigation in the detection of irradiation of whole spices. The combined DEFT+APC procedure was found to give a fairly reliable indication of whether or not a whole spice sample had been irradiated. The results are given (8 figs, 22 refs)

  5. Comparative study of thermoluminescence detection methods for irradiated spices

    International Nuclear Information System (INIS)

    Kawamura, Y.; Kojima, K.; Sugita, T.; Yamada, T.; Saito, Y.

    1995-01-01

    The thermoluminescence (TL) detection methods for irradiated spices were compared using spice samples obtained on the Japanese market, irradiated at doses of 1, 5, 10 and 30 kGy and stored for 1 year before analysis. The TL intensities of irradiated spices were stable for 1 year after irradiation. Measurement with whole samples failed to identify irradiated samples. Minerals were separated from spices in sodium tungstate saturated solution and/or sodium polytungstate solution. The TL intensity of minerals which had undergone irradiation was significantly increased for all samples. However, the ranges of TL intensity of irradiated and unirradiated samples overlapped. Clear discrimination has been obtained between the TL ratios of irradiated and unirradiated spices by using normalized measurement with reirradiation. The detection limit in terms of irradiation dose is 1 kGy even in a sample that has been irradiated 1 year prior to analysis. Normalization is the best technique currently available for thermoluminescence analysis to identify irradiated spices

  6. Alternative method of portable irradiation of manganese sulphate solution by an plutonium-beryllium source for manganese sulphate bath efficiency measurements

    International Nuclear Information System (INIS)

    Silva, Fellipe Souza da; Martins, Marcelo Marques; Pereira, Walsan Wagner

    2016-01-01

    This study intends to create an alternative irradiation system from a Plutonium-Beryllium source for manganese sulphate solution using the Monte Carlo code. Thus seeking to eliminate the issue of institutes that do not have reactors or particle accelerators in its infrastructure, in order to optimize and provide independence for them to carry out efficiency measurements of MnSO_4 solution in their own locality. The Monte Carlo simulations defined the technical features of this new system so that the solution reaches the maximum neutron capture by manganese in solution. (author)

  7. Detection methods of irradiated foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    Ponta, C C; Cutrubinis, M; Georgescu, R [IRASM Center, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-077125 Magurele-Bucharest (Romania); Mihai, R [Life and Environmental Physics Department, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-077125 Magurele-Bucharest (Romania); Secu, M [National Institute of Materials Physics, Bucharest (Romania)

    2005-07-01

    Full text: Food irradiation has, in certain circumstances, an important role to play both in promoting food safety and in reducing food losses. The safety and availability of nutritious food are essential components of primary health care. WHO actively encourages the proper use of food irradiation in the fight against foodborne diseases and food losses. To this end, it collaborates closely with FAO and IAEA. Food irradiation can have a number of beneficial effects, including delay of ripening and prevention of sprouting; control of insects, parasites, helminths, pathogenic and spoilage bacteria, moulds and yeasts; and sterilization, which enables commodities to be stored unrefrigerated for long periods. The 1990s witnessed a significant advancement in food irradiation processing. As a result, progress has been made in commercialization of the technology, culminating in greater international trade in irradiated foods and the implementation of differing regulations relating to its use in many countries. Codex General Standard for Irradiated Foodstuffs and Recommended International Code of Practice for the Operation of Irradiation Facilities Used for the Treatment of Foods regulate food irradiation at international level. At European Union level there are in power Directive 1999/2/EC and Directive1999/3/EC. Every particular country has also its own regulations regarding food irradiation. In Romania, since 2002 the Norms Regarding Foodstuffs and Food Ingredients Treated by Ionizing Radiation are in power. These Norms are in fact the Romanian equivalent law of the European Directives 1999/2/EC and 1999/3/EC. The greater international trade in irradiated foods has led to the demand by consumers that irradiated food should be clearly labeled as such and that methods capable of differentiating between irradiated and nonirradiated products should be available. Thus a practical basis was sought to allow consumers to exercise a free choice as to which food they purchase. If a

  8. Preparation of metallic nanoparticles by irradiation in starch aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Nemţanu, Monica R., E-mail: monica.nemtanu@inflpr.ro; Braşoveanu, Mirela, E-mail: monica.nemtanu@inflpr.ro; Iacob, Nicuşor, E-mail: monica.nemtanu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Electron Accelerators Laboratory, 409 Atomiştilor St., PO Box MG-36, 077125, Bucharest-Măgurele (Romania)

    2014-11-24

    Colloidal silver nanoparticles (AgNPs) were synthesized in a single step by electron beam irradiation reduction of silver ions in aqueous solution containing starch. The nanoparticles were characterized by spectrophotocolorimetry and compared with those obtained by chemical (thermal) reduction method. The results showed that the smaller sizes of AgNPs were prepared with higher yields as the irradiation dose increased. The broadening of particle size distribution occurred by increasing of irradiation dose and dose rate. Chromatic parameters such as b* (yellow-blue coordinate), C* (chroma) and ΔE{sub ab} (total color difference) could characterize the nanoparticles with respect of their concentration. Hue angle h{sup o} was correlated to the particle size distribution. Experimental data of the irradiated samples were also subjected to factor analysis using principal component extraction and varimax rotation in order to reveal the relation between dependent variables and independent variables and to reduce their number. The radiation-based method provided silver nanoparticles with higher concentration and narrower size distribution than those produced by chemical reduction method. Therefore, the electron beam irradiation is effective for preparation of silver nanoparticles using starch aqueous solution as dispersion medium.

  9. Method of detecting irradiated pepper

    International Nuclear Information System (INIS)

    Doumaru, Takaaki; Furuta, Masakazu; Katayama, Tadashi; Toratani, Hirokazu; Takeda, Atsuhiko

    1989-01-01

    Spices represented by pepper are generally contaminated by microorganisms, and for using them as foodstuffs, some sterilizing treatment is indispensable. However, heating is not suitable to spices, accordingly ethylene oxide gas sterilization has been inevitably carried out, but its carcinogenic property is a problem. Food irradiation is the technology for killing microorganisms and noxious insects which cause the rotting and spoiling of foods and preventing the germination, which is an energy-conserving method without the fear of residual chemicals, therefore, it is most suitable to the sterilization of spices. In the irradiation of lower than 10 kGy, the toxicity test is not required for any food, and the irradiation of spices is permitted in 20 countries. However, in order to establish the international distribution organization for irradiated foods, the PR to consumers and the development of the means of detecting irradiation are the important subjects. The authors used pepper, and examined whether the hydrogen generated by irradiation remains in seeds and it can be detected or not. The experimental method and the results are reported. From the samples without irradiation, hydrogen was scarcely detected. The quantity of hydrogen generated was proportional to dose. The measuring instrument is only a gas chromatograph. (K.I.)

  10. Identification methods for irradiated wheat

    International Nuclear Information System (INIS)

    Zhu Shengtao; Kume, Tamikazu; Ishigaki, Isao.

    1992-02-01

    The effect of irradiation on wheat seeds was examined using various kinds of analytical methods for the identification of irradiated seeds. In germination test, the growth of sprouts was markedly inhibited at 500Gy, which was not affected by storage. The decrease in germination percentage was detected at 3300Gy. The results of enzymatic activity change in the germ measured by Vita-Scope germinator showed that the seeds irradiated at 10kGy could be identified. The content of amino acids in ungerminated and germinated seeds were analyzed. Irradiation at 10kGy caused the decrease of lysine content but the change was small which need very careful operation to detect it. The chemiluminescence intensity increased with radiation dose and decreased during storage. The wheat irradiated at 10kGy could be identified even after 3 months storage. In the electron spin resonance (ESR) spectrum analysis, the signal intensity with the g value f 2.0055 of skinned wheat seeds increased with radiation dose. Among these methods, germination test was the most sensitive and effective for identification of irradiated wheat. (author)

  11. Detection methods for irradiated food

    International Nuclear Information System (INIS)

    Stevenson, M.H.

    1993-01-01

    The plenary lecture gives a brief historical review of the development of methods for the detection of food irradiation and defines the demands on such methods. The methods described in detail are as follows: 1) Physical methods: As examples of luminescence methods, thermoluminescence and chermoluminescence are mentioned; ESR spectroscopy is discussed in detail by means of individual examples (crustaceans, frutis and vegetables, spieces and herbs, nuts). 2) Chemical methods: Examples given for these are methods that make use of alterations in lipids through radiation (formation of long-chain hydrocarbons, formation of 2-alkyl butanones), respectively radiation-induced alterations in the DNA. 3) Microbiological methods. An extensive bibliography is appended. (VHE) [de

  12. Identification methods of irradiated food

    International Nuclear Information System (INIS)

    Raffi, J.J.

    1991-01-01

    After a general review of the different possible methods, the stress is put upon the ones close to application: electron spin resonance, thermoluminescence and method of lipids. The problem of the specificity of each method is discussed (proof or presumption): they are then placed in the context of the programme of identification of irradiated foods just co-organized by the author with the Community Bureau of Reference (CEC) [fr

  13. Physicochemical Characteristics and Biological Activity of Irradiated Pectin Solution

    International Nuclear Information System (INIS)

    Kwon, J.H.; Kang, H.J.; Jo, C.O.; Jeong, I.Y.; Byun, M.W.

    2005-01-01

    Pectin was dissolved in HCI, citric acid, and deionized distilled water (DW, 2%, v/v) and irradiated at different irradiation doses (2.5-50 kGy) by gamma ray to investigate its physicochemical characteristics and biological activity. Viscosity of pectin solution was significantly decreased by irradiation up to 10 kGy, then remained constant thereafter. Gamma-irradiation increased monosaccharide and polysaccharide levels up to 30-40 kDa. Electron donating ability of pectin solution was highest when DW was added was increased by increasing irradiation dose (p less than 0.05)

  14. γ-Irradiation-induced radiolysis of inulin in aqueous solutions

    International Nuclear Information System (INIS)

    Tsyba, I.A.; Revina, A.A.; Shostenko, A.G.

    1997-01-01

    Radiochemical transformations of inulin in aqueous solutions, in air, in the presence of inert gases, helium, nitrogen and in nitrous oxide exposed to various doses of 60 Co γ-irradiation were investigated. It was shown that interactions in inulin with OH radicals are principally responsible for radiolytic decomposition of inulin. The data on radiolysis of more simple model systems were used to make available decomposition spectra of γ-irradiated aerated aqueous solution of inulin. 9 refs., 6 figs

  15. Modelling a gamma irradiation process using the Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Gabriela A.; Pereira, Marcio T., E-mail: gas@cdtn.br, E-mail: mtp@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    In gamma irradiation service it is of great importance the evaluation of absorbed dose in order to guarantee the service quality. When physical structure and human resources are not available for performing dosimetry in each product irradiated, the appliance of mathematic models may be a solution. Through this, the prediction of the delivered dose in a specific product, irradiated in a specific position and during a certain period of time becomes possible, if validated with dosimetry tests. At the gamma irradiation facility of CDTN, equipped with a Cobalt-60 source, the Monte Carlo method was applied to perform simulations of products irradiations and the results were compared with Fricke dosimeters irradiated under the same conditions of the simulations. The first obtained results showed applicability of this method, with a linear relation between simulation and experimental results. (author)

  16. Modelling a gamma irradiation process using the Monte Carlo method

    International Nuclear Information System (INIS)

    Soares, Gabriela A.; Pereira, Marcio T.

    2011-01-01

    In gamma irradiation service it is of great importance the evaluation of absorbed dose in order to guarantee the service quality. When physical structure and human resources are not available for performing dosimetry in each product irradiated, the appliance of mathematic models may be a solution. Through this, the prediction of the delivered dose in a specific product, irradiated in a specific position and during a certain period of time becomes possible, if validated with dosimetry tests. At the gamma irradiation facility of CDTN, equipped with a Cobalt-60 source, the Monte Carlo method was applied to perform simulations of products irradiations and the results were compared with Fricke dosimeters irradiated under the same conditions of the simulations. The first obtained results showed applicability of this method, with a linear relation between simulation and experimental results. (author)

  17. Polymerization of calcium caseinates solutions induced by gamma irradiation

    International Nuclear Information System (INIS)

    Lacroix, M.; Jobin, M.; Mezgheni, E.; Srour, M.; Boileau, S.

    1998-01-01

    Solutions of calcium caseinate (5%) combined with propylene glycol (PG) or triethylene glycol(TEG) (0, 2.5% and 5%) and used for the development of edible films and coatings, were irradiated at doses between 0 to 128 kGy. Solutions were chromatographed through toyopearl HW 55F resin to observe the effect of irradiation on cross-link reactions. In unirradiated calcium caseinate solutions, two peaks could be observed (fractions 30 and 37) while samples irradiated at 64 kGy and 128 kGy showed one shifted peak at fraction 32 and 29 respectively. No effect of the plasticizers was observed. According to proteins standards of knowed molecular weights, the molecular weight of calcium caseinate increased approximately 10 times when irradiated at 128 kGy and 5 times when irradiated at 64 kGy. The physico-chemical properties of bio-films prepared with the irradiated solutions, demonstrated that tensile strength at break increased with increase of irradiation dose. A maximum dose was obtained at 16 kGy

  18. LET effect on irradiation of hydroxyphthal imide in alcohol solutions

    International Nuclear Information System (INIS)

    Nakagawa, S.; Murakami, T.

    2005-01-01

    Hydroxyphthalimide(C 6 H 4 (CO) 2 -NOH) was irradiated with C ion (290MeV/u) in isopropyl alcohol, methanol, ethanol, and acetonitrile. LET was 13.2 and 26.5 keV/m. Dose was 5 and 10 kGy. A little amount of phthalimide was produced. The G value of the production of phthalimide by ion irradiation was less than that by -irradiation except for in methanol. In methanol solution, the production rate of phthalimide increased with increasing the value of LET. The amount of the substitution for C 6 H 4 (CO) 2 -NOD in methanol-d decreased by ion irradiation. These results suggest that the reaction mechanism in ion irradiation is different from -irradiation. (author)

  19. Detection methods for irradiated mites and insects

    International Nuclear Information System (INIS)

    Ignatowicz, S.

    1999-01-01

    Results of the study on the following tests for separation of irradiated pests from untreated ones are reported: (a) test for identification of irradiated mites (Acaridae) based on lack of fecundity of treated females; (b) test for identification of irradiated beetles based on their locomotor activity; (c) test for identification of irradiated pests based on electron spin resonance (ESR) signal derived from treated insects; (d) test for identification of irradiated pests based on changes in the midgut induced by gamma radiation; and (e) test for identification of irradiated pests based on the alterations in total proteins of treated adults. Of these detection methods, only the test based on the pathological changes induced by irradiation in the insect midgut may identify consistently either irradiated larvae or adults. This test is simple and convenient when a rapid processing technique for dehydrating and embedding the midgut is used. (author)

  20. Experimental and theoretical study of solid solution stability under irradiation

    International Nuclear Information System (INIS)

    Cauvin, Richard.

    1981-08-01

    The behavior of dilute alloys (Al-Zn, Al-Ag, Al-Si, Al-Ge and Al-Mg) under 1 MeV electron irradiation has been studied in a high voltage electron microscope. A phenomenon of homogeneous precipitation induced by irradiation in undersaturated solid solutions (Al-Zn, Al-Ag and Al-Si) has been discovered; the observed precipitates are either coherent or incoherent, but never associated with point defect sinks. The solubility limit is a function of irradiation temperature and flux; but, under irradiation, it does not behave as a true thermal solubility limit (without irradiation). The existing theories (kinetic or strictly thermodynamic) do not account for this phenomenon. It is shown that the irreversibility of the mutual recombination between trapped vacancies and mixed interstitials is the driving force of this homogeneous precipitation. Using a dilute solid solution model, we show that, under irradiation, the homogeneous stationary state, stable from a strictly thermodynamic point of view, can be unstable when the recombination reaction is taken into account. The solubility limit under irradiation is calculated with a nucleation-growth model taking account for this effect; it is proportional to the thermal solubility limit without irradiation. This model explains all the experimental observations [fr

  1. Lyoluminescence technique as an identification method for irradiated food stuffs

    International Nuclear Information System (INIS)

    Chazhoor, J.S.

    1988-01-01

    The paper presents the studies made on the suitability of lyoluminescence technique as an analytical method for the identification of irradiated food stuffs. Powder milk, cinnamon, cardamom, clove, red chilly, cocoa, pepper, tea, coffee, turmeric and coriander showed lyoluminescence response when irradiated by a 10 kGy 60 Co and dissolved in luminol solution. Various dosimetric parameters such as effect of storage time, proportionality of the lyoluminescence response to dose etc were studied. (author). 1 tab., 3 figs

  2. Irradiation degradation of chlorpyrifos in water solution and asparagus

    International Nuclear Information System (INIS)

    Zhang Qingfang; Wang Feng; Ha Yiming; Li An; Yin Qinggang

    2009-01-01

    In order to seek an effective technique to degrade chlorpyrifos residue, chlorpyrifos water solution and asparagus containing chlorpyrifos as testing materials were irradiated by 60 Co γ-rays and their degradation rate were determined and compared. The results show the degradation rate in water-solution increases with irradiation dose in the range of 0 and 12 kGy, and it reached 95.5% at 4 kGy. The degradation rate of chlorpyrifos in asparagus is low and comes to the maximum of 30.0% when the dose is 8 kGy. Further study indicates that vitamin C, violaquercitrin and total sugar inhibit the irradiation degradation of chlorpyrifos in asparagus. (authors)

  3. Aqueous solution of basic fuchsin as food irradiation dosimeter

    International Nuclear Information System (INIS)

    Khan, H.M.; Naz, S.

    2006-01-01

    Dosimetric characterization of aqueous solution of basic fuchsin has been studied spectrophotometrically for the possible application in the low-dose food irradiation dosimetry. Absorption spectra of unirradiated and irradiated solutions were determined and decrease in the absorption with the radiation dose was noted down. Radiation-induced bleaching of the dye was measured at wavelengths of maximum absorption λ max (540nm) as well as 510, 460 and 400 nm wavelengths. At all these wavelengths, the decrease in the absorbance of the dosimeter was linear with respect to the absorbed dose from 0.05 to 0.6 kGy. The stability of dosimetric solution during the post-irradiation storage in the dark at room temperature showed that after initial bleaching during first eight days, the response was almost stable for about 34 days. The effect of different light and temperature conditions also showed that the response gradually decreased during the storage period of 34 days, which shows that the basic fuchsin dye is photosensitive as well as thermally sensitive. The possibility of using aqueous solution of basic fuchsin as food irradiation dosimeter will be discussed. (authors)

  4. Analytical detection methods for irradiated foods

    International Nuclear Information System (INIS)

    1991-03-01

    The present publication is a review of scientific literature on the analytical identification of foods treated with ionizing radiation and the quantitative determination of absorbed dose of radiation. Because of the extremely low level of chemical changes resulting from irradiation or because of the lack of specificity to irradiation of any chemical changes, a few methods of quantitative determination of absorbed dose have shown promise until now. On the other hand, the present review has identified several possible methods, which could be used, following further research and testing, for the identification of irradiated foods. An IAEA Co-ordinated Research Programme on Analytical Detection Methods for Irradiation Treatment of Food ('ADMIT'), established in 1990, is currently investigating many of the methods cited in the present document. Refs and tab

  5. Irradiation alternative method of manganese sulfate solution by a Pu-Be source for efficiency measurements; Metodo alternativo de irradiacao da solucao de sulfato de manganes por uma fonte de Pu-Be para medicoes de eficiencia

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Fellipe Souza da; Martins, Marcelo Marques; Pereira, Walsan Wagner, E-mail: fellipess@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    This study intends to create an alternative irradiation system from a Plutonium-Beryllium source for manganese sulphate solution using the Monte Carlo code. Thus seeking to eliminate the issue of institutes that do not have reactors or particle accelerators in its infrastructure, in order to optimize and provide independence for them to carry out efficiency measurements of MnSO{sub 4} solution in their own locality. The Monte Carlo simulations defined the technical features of this new system so that the solution reaches the maximum neutron capture by manganese in solution. (author)

  6. Detection of food irradiation - two analytical methods

    International Nuclear Information System (INIS)

    1994-01-01

    This publication summarizes the activities of Nordic countries in the field of detection of irradiated food. The National Food Agency of Denmark has coordinated the project. The two analytical methods investigated were: the gas-chromatographic determination of the hydrocarbon/lipid ratio in irradiated chicken meat, and a bioassay based on microelectrophoresis of DNA from single cells. Also a method for determination of o-tyrosine in the irradiated and non-irradiated chicken meat has been tested. The first method based on radiolytical changes in fatty acids, contained in chicken meat, has been tested and compared in the four Nordic countries. Four major hydrocarbons (C16:2, C16:3, C17:1 and C17:2) have been determined and reasonable agreement was observed between the dose level and hydrocarbons concentration. Results of a bioassay, where strand breaks of DNA are demonstrated by microelectrophoresis of single cells, prove a correlation between the dose levels and the pattern of DNA fragments migration. The hydrocarbon method can be applied to detect other irradiated, fat-containing foods, while the DNA method can be used for some animal and some vegetable foods as well.Both methods allow to determine the fact of food irradiation beyond any doubt, thus making them suitable for food control analysis. The detailed determination protocols are given. (EG)

  7. Treatment of chlorofluorocarbons in alcohol solutions by γ-irradiation

    International Nuclear Information System (INIS)

    Shimokawa, Toshinari; Nakagawa, Seiko; Sawai, Teruko

    1995-01-01

    A study was done on dechlorination of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC113) in neutral and alkaline alcohol solutions by means of γ-irradiation. The dechlorination yield (G (Cl - )) was found to depend on the kind of alcohol used as solvents and the presence of hydroxide ion. The order of G (Cl - ) value in alkaline solution was isopropyl alcohol>> ethyl alcohol > methyl alcohol. It was suggested that the high yield obtained in alkaline isopropyl alcohol solution is explained by a chain process in dechlorination reaction. In case of alkaline isopropyl alcohol solution, CFC113 was dechlorinated to lower chlorinated ethane, and 1,1-dichloro-1,2,2-trifluoroetane was a main product. We have discussed on the chain dechlorination mechanism in alkaline isopropyl alcohol solution. (author)

  8. Cytosine modifications after gamma irradiation in aerated aqueous solution of Escherichia coli DNA

    International Nuclear Information System (INIS)

    Polverelli, M.

    1983-04-01

    After gamma irradiation of cytosine in aerated aqueous solution and utilization of various spectrometric methods (mass spectrometry, proton nuclear magnetic resonance and infrared spectrometry) about ten new radiolysis products were identified. The formation of N-glycolylbiuret in H 2 18 O aqueous solution of irradiated cytosine at pH 4,5 indicated that the preferred 18 OH hydroxyl radical attack was at C-5. The formation of trans 1-carbamoyl-4,5 dihydroxyimidazolidin-2 oxo which is the major product after cytosine pyrimidine ring rearrangement took place preferentially at neutral pH, while N-glycolylbiuret predominated at pH 4,5. The deamination pathway was predominant when cytosine was irradiated at acidic pH values (pH 2 ) or in copper complexes. The development of a new acid hydrolysis method using fluorhydric acid stabilized in pyridine made easier the evaluation of cytosine modifications after gamma irradiation in aerated aqueous solution of E. Coli DNA- 14 C-2 cytosine. This hydrolytic agent removed the modified bases from the polynucleotidic chain. A difference was found between the proportion of radiolytic products removed by acid hydrolysis and by irradiation of the free base in solution [fr

  9. A method for total body irradiation

    International Nuclear Information System (INIS)

    Yasukochi, Hiroshi; Higashi, Shizuka; Okuhata, Yoshitaka; Lee, Keiichi; Ishioka, Kuniaki; Murakami, Koji; Nagai, Jun; Kuniyasu, Yoshio

    1988-01-01

    In these two years, we have treated four infant patients of acute leukemia by Cobalt-60 total body irradiation and bone marrow transplantation. During total body irradiation, thermoluminescence dosimeters were attached to the skin of patients. For four patients, nine dosimetries were performed. Reliability of this method was examined by phantom experiment. Every irradiation for the patient per fraction was 2.4 Gy, that is, 60 cGy for each four positions, right decubitus A-P and PA directions and left decubitus A-P and PA directions under aseptic circumstances. Radiation dose was uniform by this technique for each patient, and average determined dose for surface of the patients was between 87 % and 106 % compared with the air dose of the center of aseptic space (wagon). As the result, we suggest that this method is suitable for the total body irradiation of acute leukemia of infant. (author)

  10. Detection of food irradiation with luminescence methods

    International Nuclear Information System (INIS)

    Anderle, H.

    1997-06-01

    Food irradiation is applied as method for the preservation of foods, the prevention of food spoilage and the inhibition of food-borne pathogens. Doses exceeding 10 kGy (10 kJ/kg) are not recommended by the WHO. The different legislation requires methods for the detection and the closimetry of irradiated foods. Among the physical methods based on the radiation-induced changes in inorganic, nonhygroscopic crystalline solids are thermoluminescence (TL), photostimulated luminescence (PSL) and lyoluminescence (LL) measurement. The luminescence methods were tested on natural minerals. Pure quartz, feldspars, calcite, aragonite and dolomite of known origin were irradiated, read out and analyzed to determine the influence of luminescence-activators and deactivators. Carbonate minerals show an orange-red TL easily detectable by blue-sensitive photomultiplier tubes. TIL-inactive carbonate samples may be identified by a lyoluminescence method using the reaction of trapped irradiation-generated charge carriers with the solvent during crystal-lattice breakup. The fine-ground mineral is dissolved in an alkaline complexing agent/chemiluminescence sensitizer/chemiluminescence catalyst (EDTA/luminol/hemin) reagent mixture. The TL and PSL of quartz is too weak to contribute a significant part for the corresponding signals in polymineral dust. Alkali and soda feldspar show intense TL and PSL. The temperature maxima in the TL glow curves allow a clear distinction. PSL does not give this additional information, it suffers from bleaching by ambient light and requires light-protection. Grain disinfestated with low irradiation doses (500 Gy) may not identified by both TL and PSL measurement. The natural TL of feldspar particles may be overlap with the irradiation-induced TL of other minerals. As a routine method, irradiated spices are identified with TL measurement. The dust particles have to be enriched by heavy-liquid flotation and centrifugation. The PSL method allows a clear

  11. Thermoluminescence method for detection of irradiated food

    International Nuclear Information System (INIS)

    Pinnioja, S.

    1998-01-01

    A method of thermoluminescence (TL) analysis was developed for the detection of irradiated foods. The TL method is based on the determination of thermoluminescence of adhering or contaminating minerals separated from foods by wet sieving and treatment with high density liquid. Carbon tetrachloride provided a suitable alternative for foods that form gels with water. Thermoluminescence response of minerals in a first TL measurement is normalised with a second TL measurement of the same mineral sample after calibration irradiation to a dose of 5 kGy. The decision about irradiation is made on the basis of a comparison of the two TL spectra: if the two TL glow curves match in shape and intensity the sample has been irradiated, and if they are clearly different it has not been irradiated. An attractive feature of TL analysis is that the mineral material itself is used for calibration; no reference material is required. Foods of interest in the investigation were herbs, spices, berries and seafood. The presence of minerals in samples is a criterion for application of the method, and appropriate minerals were found in all herbs, spices and berries. The most common minerals in terrestrial food were tecto-silicates - quartz and feldspars - which with their intense and stable thermoluminescence were well suited for the analysis. Mica proved to be useless for detection purposes, whereas carbonate in the form of calcite separated from intestines of seafood was acceptable. Fading of the TL signal is considerable in the low temperature part of the glow curve during a storage of several months after irradiation. However, spices and herbs could easily be identified as irradiated even after two years storage. Conditions for seafood, which is stored in a freezer, are different, and only slight fading was observed after one year. The effect of mineral composition and structure on TL was studied for feldspars. Feldspars originating from subtropical and tropical regions exhibit lower TL

  12. Thermoluminescence method for detection of irradiated food

    Energy Technology Data Exchange (ETDEWEB)

    Pinnioja, S

    1998-12-31

    A method of thermoluminescence (TL) analysis was developed for the detection of irradiated foods. The TL method is based on the determination of thermoluminescence of adhering or contaminating minerals separated from foods by wet sieving and treatment with high density liquid. Carbon tetrachloride provided a suitable alternative for foods that form gels with water. Thermoluminescence response of minerals in a first TL measurement is normalised with a second TL measurement of the same mineral sample after calibration irradiation to a dose of 5 kGy. The decision about irradiation is made on the basis of a comparison of the two TL spectra: if the two TL glow curves match in shape and intensity the sample has been irradiated, and if they are clearly different it has not been irradiated. An attractive feature of TL analysis is that the mineral material itself is used for calibration; no reference material is required. Foods of interest in the investigation were herbs, spices, berries and seafood. The presence of minerals in samples is a criterion for application of the method, and appropriate minerals were found in all herbs, spices and berries. The most common minerals in terrestrial food were tecto-silicates - quartz and feldspars - which with their intense and stable thermoluminescence were well suited for the analysis. Mica proved to be useless for detection purposes, whereas carbonate in the form of calcite separated from intestines of seafood was acceptable. Fading of the TL signal is considerable in the low temperature part of the glow curve during a storage of several months after irradiation. However, spices and herbs could easily be identified as irradiated even after two years storage. Conditions for seafood, which is stored in a freezer, are different, and only slight fading was observed after one year. The effect of mineral composition and structure on TL was studied for feldspars. Feldspars originating from subtropical and tropical regions exhibit lower TL

  13. Aqueous solution of basic fuchsin as food irradiation dosimeter

    International Nuclear Information System (INIS)

    Khan, H.M.; Naz, S.

    2007-01-01

    Dosimetric characterization of aqueous solution of basic fuchsin was studied spectrophotometrically for possible application in the low-dose food irradiation dosimetry. Absorption spectra of unirradiated and irradiated solutions were determined and the decrease in absorbance with the dose was noted down. Radiation-induced bleaching of the dye was measured at wavelengths of maximum absorption λ max (540nm) as well as 510nm and 460 nm. At all these wavelengths, the decrease in absorbance of the dosimeter was linear with respect to the absorbed dose from 50 Gy to 600 Gy. The stability of dosimetric solution during post-irradiation storage in the dark at room temperature showed that after initial bleaching during first ten to twenty days, the response was almost stable for about 34 days. The study on the effect of different light and temperature conditions also showed that the response gradually decreased during the storage period of 34 days, which shows that basic fuchsin dye is photosensitive as well as thermally sensitive. (authors)

  14. Iodine volatilization from irradiated CsI solutions

    Energy Technology Data Exchange (ETDEWEB)

    Evans, G J; Panyan, E J [Toronto Univ., ON (Canada). Dept. of Chemical Engineering and Applied Chemistry

    1996-12-01

    A bench-scale, separate-effect, flow apparatus has been constructed to examine volatile iodine production rates in relation to a selection of the possible variables and conditions found in a containment structure with a breached reactor core. The constructed apparatus is designed to provide the widest possible range of data including gas and aqueous phase speciation for an established set of interfacial mass transfer parameters with known pH and dissolved oxygen levels. As the interfacial transfer of iodine is an important component in the understanding of iodine chemistry, commissioning of the constructed apparatus focused on establishing a well characterized set of mass transfer parameters for a variety of mixing conditions and solution volumes. Aqueous phase parameters, obtained using a method involving the sparging of the dissolved oxygen in the aqueous phase, were found to vary by one order of magnitude, from 1x10{sup -2} to 1x10{sup -3} dm/sec. Gas phase parameters also changeable by one order of magnitude, from 1x10{sup -1} to 1x10{sup -2} dm/sec, were studied more thoroughly as they were found to have a greater impact in the system. Two independent methods of analysis were used, one involving tri-iodide solutions, the other using relative humidity values. A selection of the acquired volatility rates in relation to the effect of pH are presented. The apparatus has been found to consistently provide rates up to one order of magnitude lower than modelled predictions. Specifically, for buffered solutions, rates of 2x10{sup -12} mol/min and 1x10{sup -10} mol/min for pH 9 and 5 respectively, have been found. Rates of 1x10{sup -11} mol/min and 6x10{sup -10} mol/min are predicted. Current efforts have addressed potential reasons for this apparent discrepancy, the major factor being the possible release of components from the stainless steel during irradiation. Efforts undertaken to ensure the validity of the results are emphasized. (Abstract Truncated)

  15. Iodine volatilization from irradiated CsI solutions

    International Nuclear Information System (INIS)

    Evans, G.J.; Panyan, E.J.

    1996-01-01

    A bench-scale, separate-effect, flow apparatus has been constructed to examine volatile iodine production rates in relation to a selection of the possible variables and conditions found in a containment structure with a breached reactor core. The constructed apparatus is designed to provide the widest possible range of data including gas and aqueous phase speciation for an established set of interfacial mass transfer parameters with known pH and dissolved oxygen levels. As the interfacial transfer of iodine is an important component in the understanding of iodine chemistry, commissioning of the constructed apparatus focused on establishing a well characterized set of mass transfer parameters for a variety of mixing conditions and solution volumes. Aqueous phase parameters, obtained using a method involving the sparging of the dissolved oxygen in the aqueous phase, were found to vary by one order of magnitude, from 1x10 -2 to 1x10 -3 dm/sec. Gas phase parameters also changeable by one order of magnitude, from 1x10 -1 to 1x10 -2 dm/sec, were studied more thoroughly as they were found to have a greater impact in the system. Two independent methods of analysis were used, one involving tri-iodide solutions, the other using relative humidity values. A selection of the acquired volatility rates in relation to the effect of pH are presented. The apparatus has been found to consistently provide rates up to one order of magnitude lower than modelled predictions. Specifically, for buffered solutions, rates of 2x10 -12 mol/min and 1x10 -10 mol/min for pH 9 and 5 respectively, have been found. Rates of 1x10 -11 mol/min and 6x10 -10 mol/min are predicted. Current efforts have addressed potential reasons for this apparent discrepancy, the major factor being the possible release of components from the stainless steel during irradiation. Efforts undertaken to ensure the validity of the results are emphasized. During commissioning efforts, several problems have been identified and

  16. Effect of gamma irradiation on viscosity of aqueous solutions of some natural polymers

    International Nuclear Information System (INIS)

    Nguyen Tan Man; Truong Thi Hanh; Le Quang Luan; Le Hai; Nguyen Quoc Hien

    2000-01-01

    Effect of gamma irradiation on viscosity of aqueous solution of alginate and carbon xylmethyl cellulose (CMC) irradiated in solid state has been carried out. the viscosity of aqueous solution of alginate and CMC decreased remarkably with increasing dose and the viscosity of 2% solution of above polymers irradiated at 50 kGy was about 100 times lower than the original one. (author)

  17. Corrosion of non-irradiated UAl{sub x}-Al fuel in the presence of clay pore solution. A quantitative XRD secondary phase analysis applying the DDM method

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, Andreas [Halle-Wittenberg Univ. (Germany). Dept. of Mineralogy and Geochemistry; RWTH Aachen Univ. (Germany). Inst. of Crystallography; Klinkenberg, Martina; Curtius, Hildegard [Forschungszentrum Juelich GmbH (Germany). Inst. of Energy and Climate Research, IEK-6 Nuclear Waste Management

    2017-04-01

    Corrosion experiments with non-irradiated metallic UAl{sub x}-Al research reactor fuel elements were carried out in autoclaves to identify and quantify the corrosion products. Such compounds, considering the long-term safety assessment of final repositories, can interact with the released inventory and this constitutes a sink for radionuclide migration in formation waters. Therefore, the metallic fuel sample was subjected to clay pore solution to investigate its process of disintegration by analyzing the resulting products and the remnants, i.e. the secondary phases. Due to the fast corrosion rate a full sample disintegration was observed within the experimental period of 1 year at 90 C. The obtained solids were subdivided into different grain size fractions and prepared for analysis. The elemental analysis of the suspension showed that, uranium and aluminum are concentrated in the solids, whereas iron was mainly dissolved. Non-ambient X-ray diffraction (XRD) combined with the derivative difference minimization (DDM) method was applied for the qualitative and quantitative phase analysis (QPA) of the secondary phases. Gypsum and hemihydrate (bassanite), residues of non-corroded nuclear fuel, hematite, and goethite were identified. The quantitative phase analysis showed that goethite is the major crystalline phase. The amorphous content exceeded 80 wt% and hosted the uranium. All other compounds were present to a minor content. The obtained results by XRD were well supported by complementary scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis.

  18. Irradiation monitoring of spices by chemiluminescence method

    International Nuclear Information System (INIS)

    Bhatti, K.A.; Khan, H.M.; Sattar, A.; Ahmad, A.

    2001-01-01

    Some spices (cumin, coriander, black pepper and red pepper), commonly used due to their specific aroma and nutritional value were studied using chemiluminescence (CL) method to test whether the food has been irradiated or not. The spices were ground to different mesh sizes and subjected to gamma ray doses of 2.5, 5.0, 7.5 and 10 Kgy. The effect of radiation doses and particle size on the CL response of irradiated and un-irradiated samples was checked using luminol and lucigenin sensitizers. The storage experiment was also performed for all spices with both the sensitizers in order to pick the suitable sensitizer for CL study. During this study Co-60 gamma ray source and Bio-orbit 1250 luminometer were used after precise calibration

  19. Decoloration and degradation of Reactive Red-120 dye by electron beam irradiation in aqueous solution

    International Nuclear Information System (INIS)

    Paul, Jhimli; Rawat, K.P.; Sarma, K.S.S.; Sabharwal, S.

    2011-01-01

    The decoloration and degradation of aqueous solution of the reactive azo dye viz. Reactive Red-120 (RR-120) was carried out by electron beam irradiation. The change in decoloration percentage, removal of chemical oxygen demand (COD) and total organic carbon (TOC), solution pH and five-day biochemical oxygen demand (BOD 5 ) were investigated with respect to the applied dose. However, the concentration of the dye in the solution showed a great influence on all these observables. During the radiolysis process, it was found that the decoloration of dye was caused by the destruction of the chromophore group of the dye molecule, whereas COD and TOC removal were depended on the extent of mineralization of the dye. The decrease in pH during the radiolysis process indicated the fragmentation of the large dye molecule into smaller organic components mostly like smaller organic acids. The BOD 5 /COD ratio of the unirradiated dye solution was in the range of 0.1-0.2, which could be classified as non-biodegradable wastewater. However, the BOD 5 /COD ratio increased upon irradiation and it indicated the transformation of non-biodegradable dye solution into biodegradable solution. This study showed that electron beam irradiation could be a promising method for treatment of textile wastewater containing RR-120 dye.

  20. Effect of 60Co gamma-ray irradiation on dilute aqueous solutions of surfactants

    International Nuclear Information System (INIS)

    Sawai, Teruko; Shimokawa, Toshinari; Miki, Yasushi; Oseko, Koichi; Sawai, Takeshi

    1978-01-01

    Present work deals with the effects of gamma irradiation from 60 Co γ-ray source upon aqueous solutions of three kinds of surfactants. When dilute aqueous solutions of sodium dodecyl sulfate (SDS, anionic), cethyl trimethyl ammonium chloride (CTAC, cationic), and polyoxyethylene lauryl ether (POE, non-ionic) were irradiated with γ-rays at a room temperature, the residual concentration, products, surface tension, and forming power were examined by colorimetric method, IR spectrophotometric method, gaschromatography, Ross-Miles method, and Traube's stalagmometer etc. These surfactants were decomposed by the irradiation and thus the surface tension increased and the forming power, on the contrary, decreased with dose. Radiation chemical yields (G-value) of the degradation were about 1 for the solutions of SDS and CTAC, and about 0.3 for the POE solution. From the experimental results, it was found that following chemical reactions seem to occur followed by the radiolysis of water: a) bond cleavage of ester for SDS, of CN for CTAC, and of oxyethylene for POE, b) hydrogen abstraction from the surfactants, c) production of CO bond in the presence of dissolved oxygen. (auth.)

  1. [Effect of 60Co gamma-irradiation on dilute aqueous solutions of surfactants].

    Science.gov (United States)

    Sawai, T; Shimokowa, T; Miki, Y; Oseko, K; Sawai, T

    1978-01-01

    Present work deals with the effects of gamma irradiation from 60Co gamma-ray source upon aqueous solutions of three kinds of surfactants. When dilute aqueous solutions of sodium dodecyl sulfate (SDS, anionic), cethyl trimethyl ammonium chloride (CTAC, cationic), and polyoxyethylene lauryl ether (POE, non-ionic) were irradiated with gamma-rays at a room remperature, the residual concentration, products, surface tension, and forming power were examined by colorimetric method, IR spectrophotometric method, gaschromatography, Ross-Miles method, and Traube's stalagnometer etc.. These surfactants were decomposed by the irradiation and thus the surface tension increased and the forming power, on the contrary, decreased with dose. Radiation chemical yields (G-value) of the degradation were about 1 for the solutions of SDS and CTAC, and about 0.3 for the POE solution. From the experimental results, it was found that following chemical reactions seem to occur followed by the radiolysis of water; a) bond cleavage of ester for SDS, of CN for CTAC, and of oxyethylene for POE, b) hydrogen abstraction from the surfactants, c) production of CO bond in the presence of dissolved oxygen.

  2. Chemical dosimetry using an iodide/iodate aqueous solution: application to the gamma irradiation of blood

    Energy Technology Data Exchange (ETDEWEB)

    Rahn, Ronald O. E-mail: rahnr@ms.soph.uab.edu

    2003-01-01

    A method is presented for measuring and verifying the radiation dose in gamma irradiators used for treating blood prior to transfusion. This method employs the iodide/iodate dosimeter (0.6 M iodide, 0.1 M iodate, and 0.01 borate at pH 9.25) which forms triiodide upon exposure to ionizing radiation; for Cs-137 radiation the G value is 14.1. Samples were placed in a canister and irradiated in a conventional blood bank irradiator containing several Cs-137 sources. The following were exposed: (a) nine 1.5 ml plastic tubes containing dosimetry solution taped inside a 250 ml blood bag, which, in turn, was filled with either water or blood, (b) 50 ml plastic syringes containing varying amounts of dosimetry solution, (c) a whole blood bag containing 250 ml of the dosimetry solution. A water phantom was not used during exposure. The absorbance changes at 352 nm due to triiodide formation were used to determine a dose rate, which was on the order of 10 Gy/min ({+-}5%) for all samples measured. This value is consistent with an average time-decayed dose rate for the irradiation volume as determined from the manufacturers calibration of the unit taking into account the heterogeneous nature of the radiation field inside the irradiator and the absence of a water phantom. Because of its sensitivity, ease of operation, and reproducibility, it is suggested that the iodide/iodate dosimetry system be considered for on-site periodic conformation/verification of the radiation dose as part of a quality assurance requirement for blood irradiators.

  3. Chemical dosimetry using an iodide/iodate aqueous solution: application to the gamma irradiation of blood

    International Nuclear Information System (INIS)

    Rahn, Ronald O.

    2003-01-01

    A method is presented for measuring and verifying the radiation dose in gamma irradiators used for treating blood prior to transfusion. This method employs the iodide/iodate dosimeter (0.6 M iodide, 0.1 M iodate, and 0.01 borate at pH 9.25) which forms triiodide upon exposure to ionizing radiation; for Cs-137 radiation the G value is 14.1. Samples were placed in a canister and irradiated in a conventional blood bank irradiator containing several Cs-137 sources. The following were exposed: (a) nine 1.5 ml plastic tubes containing dosimetry solution taped inside a 250 ml blood bag, which, in turn, was filled with either water or blood, (b) 50 ml plastic syringes containing varying amounts of dosimetry solution, (c) a whole blood bag containing 250 ml of the dosimetry solution. A water phantom was not used during exposure. The absorbance changes at 352 nm due to triiodide formation were used to determine a dose rate, which was on the order of 10 Gy/min (±5%) for all samples measured. This value is consistent with an average time-decayed dose rate for the irradiation volume as determined from the manufacturers calibration of the unit taking into account the heterogeneous nature of the radiation field inside the irradiator and the absence of a water phantom. Because of its sensitivity, ease of operation, and reproducibility, it is suggested that the iodide/iodate dosimetry system be considered for on-site periodic conformation/verification of the radiation dose as part of a quality assurance requirement for blood irradiators

  4. Degradation and detoxification of aqueous nitrophenol solutions by electron beam irradiation

    International Nuclear Information System (INIS)

    Song Weihua; Zheng Zheng; Rami, Abual-Suud; Zhou Tao; Hang Desheng

    2002-01-01

    The goal of this research was to study the degradation of nitrophenol solutions by high-energy electron beam irradiation. The results showed that the degradation processes obey an apparent first-order degradation. At the higher irradiation doses the pH of solutions decreased; however, the dissolved organic carbon of the solutions was essentially unchanged. To investigate the toxicity of the radiolytic products the oxygen uptake rate of activated sludge was determined. The toxicity of irradiated nitrophenol solutions decreased from the initial non-irradiated solutions

  5. Numerical solution of kinetics equation for point defects accumulation in metals under irradiation

    International Nuclear Information System (INIS)

    Aldzhambekova, G.T.; Iskakov, B.M.

    1999-01-01

    In the report the mathematical model, describing processes of generation and accumulation of defects in solids under irradiation is considered. The equations of this model take into account the velocity of Frenkel pairs generation, the mutual recombination of vacancies and the interstitials, as well as velocity of defects absorption by discharge channeling of vacancies and interstitials. By Runge-Kutta method the numerical solution of the model was carried out

  6. Irradiated film material and method of the irradiation

    International Nuclear Information System (INIS)

    1978-01-01

    The irradiation of polymer film material is a strengthening procedure. To obtain a substantial uniformity in the radiation dosage profile, the film is irradiated in a trough having lateral deflection blocks adjacent to the film edges. These deflect the electrons towards the surface of the trough bottom for further deflection towards the film edge. (C.F.)

  7. Ruthenium (4) and ruthenium (3) state in hydrochloric acid solutions under microwave irradiation

    International Nuclear Information System (INIS)

    Bashilov, A.V.; Kuz'min, N.M.; Nesterov, A.A.; Runov, V.K.

    2000-01-01

    Reactions of hydration, poly- and depolymerization, oxidation-reduction processes with ruthenium (4) and ruthenium (3) participation are investigated in hydrochloric acid solutions under microwave irradiation by the methods of molecular absorption spectroscopy in UV visible region taking K 4 [Ru 2 OCl 10 ] as an example. Content of state forms of ruthenium (4) and ruthenium (3), absorption characteristics of forming complexes are calculated. Variation of microwave irradiation parameters and HCl concentration permits to prepare solutions containing [RuCl 6 ] 2+ (95 %) and [(RuOH) 2 (H 2 O) 6 (OH) 2 ] 4+ (98 %) preeminently predominant forms. The role of microwave effect directly is established taking as an example the process of ruthenium (4) hydration [ru

  8. Reaction of the H atom in gamma-irradiated ferrous sulphate solutions

    International Nuclear Information System (INIS)

    Mathews, R.W.

    1977-10-01

    The effect of sulphuric acid, ferrous and ferric ion, and oxygen concentrations on G(Fe 3+ ) values from cobalt-60 gamma-irradiated soltuions has been studied. Kinetic expressions were derived for reaction models involving reactions of various forms of the H atom and additional reactions postulated to be of importance at high solute concentration. Three models were assumed invoking the additional reactions: (1) an independent yield of an excited water species; (2) increasing contributions from interspur reactions of well established species at increasing solute concentration; (3) inhibition of charge pair recombination by acid and scavenger species. The calculated G(Fe 3+ ) values from the various models were compared by the least squares method with experimental G(Fe 3+ ) values from over 600 irradiations. Model 3 provided the best fit to the data for the least number of adjustable parameters. No evidence for more than one form of H atom was found with this model. (J.R.)

  9. The effect of gamma irradiation on rice protein aqueous solution

    Science.gov (United States)

    Baccaro, Stefania; Bal, Oya; Cemmi, Alessia; Di Sarcina, Ilaria

    2018-05-01

    The use of proteins as natural biopolymers are sensibly increasing in several application fields such as food industry, packaging and environment protection. In particular, rice proteins (RP) present good nutritional, hypoallergenic and healthful properties very interesting for human consumption. Since ionizing radiation can be successfully applied on protein containing systems involved in different industrial processes, this work aims to determine the effect of gamma radiation on 5 wt%-7.5 wt% RP aqueous solutions in a wide range of absorbed doses up to around 40 kGy. The changes of RP secondary and tertiary structures and their chemical composition were followed by UV-VIS absorbance spectroscopy, luminescence analysis and pH measurements. The experimental data showed the occurrence of the unfolding of RP chains with the increase of the absorbed dose and the formation of new molecules, due to the reaction among tryptophane and tyrosine amino acids and the radical species induced by gamma radiation. The results are also confirmed by the modification of the pH values measured for the irradiated solutions.

  10. Self-diffusion and solute diffusion in alloys under irradiation: Influence of ballistic jumps

    International Nuclear Information System (INIS)

    Roussel, Jean-Marc; Bellon, Pascal

    2002-01-01

    We have studied the influence of ballistic jumps on thermal and total diffusion of solvent and solute atoms in dilute fcc alloys under irradiation. For the diffusion components that result from vacancy migration, we introduce generalized five-frequency models, and show that ballistic jumps produce decorrelation effects that have a moderate impact on self-diffusion but that can enhance or suppress solute diffusion by several orders of magnitude. These could lead to new irradiation-induced transformations, especially in the case of subthreshold irradiation conditions. We also show that the mutual influence of thermal and ballistic jumps results in a nonadditivity of partial diffusion coefficients: the total diffusion coefficient under irradiation may be less than the sum of the thermal and ballistic diffusion coefficients. These predictions are confirmed by kinetic Monte Carlo simulations. Finally, it is shown that the method introduced here can be extended to take into account the effect of ballistic jumps on the diffusion of dumbbell interstitials in dilute alloys

  11. Degradation of phorbol 12,13-diacetate in aqueous solution by gamma irradiation

    International Nuclear Information System (INIS)

    Kongmany, Santi; Furuta, Masakazu; Matsuura, Hiroto; Okuda, Shuichi; Imamura, Kiyoshi; Maeda, Yasuaki

    2014-01-01

    Phorbol esters (PEs) are highly toxic compounds that cause skin irritation, inflammation, and tumor promotion upon contact with humans or animals. These compounds are naturally present in Jatropha curcas L. To promote the use of J. curcas seed oil in bio-diesel production industries and reduce environmental concerns, it is necessary to find methods of degrading PEs. In this study, the degradation of phorbol 12,13-diacetate (PDA), as a representative PE, in aqueous solution at a concentration of 10 mg/L by 60 Co-γ-irradiation was investigated. The results demonstrate that PDA was effectively degraded by this treatment and the degradation efficiency increased with the absorbed dose within the range of 0.5–3 kGy. Complete degradation of PDA was achieved at a dose of 3 kGy. In the presence of radical scavengers (i.e., methanol, tert-butanol, 2-propanol), reactive species from water radiolysis were scavenged, and significant inhibition of PDA degradation was observed at absorbed doses less than 1 kGy. In the presence of nitrous oxide, the generation of hydroxyl radicals (·OH) was promoted during gamma irradiation and PDA degradation was drastically enhanced. - Highlights: • PDA in aqueous solution was effectively degraded by gamma irradiation. • Hydroxyl radical mainly contributed to PDA degradation. • Intermediate product produced from PDA degradation was further decomposed. • Gamma irradiation process can be useful for degrading phorbol esters in water

  12. Detection of irradiated foods by the DEFT/APC method

    International Nuclear Information System (INIS)

    Yuecel, P. K.; Koeseoglu, T.; Halkman, H. B. D.

    2009-01-01

    Irradiation technology is used to prevent the spoilage losses and to improve the hygienic quality of foods. Appropriate techniques for the detection of irradiated foods are needed to guarantee the proper consumer information and to facilitate the trade of irradiated foods. The characteristics of the microbial population of irradiated foods have been used for developing detection methods for irradiated foods. This microbiological method is based on the comparison of an aerobic plate count (APC) with a count obtained with the direct epifluorescent filter technique (DEFT) for the detection of irradiation of foodstuffs.

  13. Infusion of solutions of pre-irradiated components in rats.

    Science.gov (United States)

    Pappas, Georgina; Arnaud, Francoise; Haque, Ashraful; Kino, Tomoyuki; Facemire, Paul; Carroll, Erica; Auker, Charles; McCarron, Richard; Scultetus, Anke

    2016-06-01

    The objective of this study was to conduct a 14-day toxicology assessment for intravenous solutions prepared from irradiated resuscitation fluid components and sterile water. Healthy Sprague Dawley rats (7-10/group) were instrumented and randomized to receive one of the following Field IntraVenous Resuscitation (FIVR) or commercial fluids; Normal Saline (NS), Lactated Ringer's, 5% Dextrose in NS. Daily clinical observation, chemistry and hematology on days 1,7,14, and urinalysis on day 14 were evaluated for equivalence using a two sample t-test (p<0.05). A board-certified pathologist evaluated organ histopathology on day 14. Equivalence was established for all observation parameters, lactate, sodium, liver enzymes, creatinine, WBC and differential, and urinalysis values. Lack of equivalence for hemoglobin (p=0.055), pH (p=0.0955), glucose (p=0.0889), Alanine-Aminotransferase (p=0.1938), albumin (p=0.1311), and weight (p=0.0555, p=0.1896), was deemed not clinically relevant due to means within physiologically normal ranges. Common microscopic findings randomly distributed among animals of all groups were endocarditis/myocarditis and pulmonary lesions. These findings are consistent with complications due to long-term catheter use and suggest no clinically relevant differences in end-organ toxicity between animals infused with FIVR versus commercial fluids. Copyright © 2016 Elsevier GmbH. All rights reserved.

  14. Formation of tyrosine isomers in aqueous phenylalanine solutions by gamma irradiation

    International Nuclear Information System (INIS)

    Aflaki, F.; Salahinejad, M.; Roozbehani, A.

    2009-01-01

    Ortho-tyrosine detection method can be used for detection of irradiated protein rich foods. Tyrosine isomers produced by gamma radiation of aqueous phenylalanine solutions at wide dose levels (0.1-50 k Gy) were examined to obtain basic information for o-tyrosine detection method of irradiated foods. Determination of tyrosines produced in aqueous phenylalanine solutions were carried out by high performance liquid chromatography and fluorescence detection. The detection limit of o-tyrosine was 0.01 ppm and the linear range of calibration and the relative standard deviation of analysis was 50 ng and 4-13%, respectively. The amounts of the tyrosines increased with the irradiation level up to 10 k Gy and no further tyrosine formation was observed when the dose level was increased. At a constant dose level, the yield of tyrosines initially increased with the phenylalanine concentration, while with further increase of phenylalanine concentration no effect on increase of tyrosine yield was observed. When the dose rate was varying from 2.3 k Gy/h to 1.2 k Gy/h with a total amount of 10 k Gy in each case, there was no significant effect on tyrosine isomers formation was observed. Also the results showed that tyrosine yield was affected by temperature, p H and the presence of oxygen

  15. Detection of irradiated spice in blend of irradiated and un-irradiated spices using thermoluminescence method

    International Nuclear Information System (INIS)

    Goto, Michiko; Yamazaki, Masao; Sekiguchi, Masayuki; Todoriki, Setsuko; Miyahara, Makoto

    2007-01-01

    Five blended spice sample were prepared by mixing irradiated and un-irradiated black pepper and paprika at different ratios. Blended black pepper containing 2%(w/w) of 5.4 kGy-irradiated black pepper showed no maximum at glow1. Irradiated black pepper samples, mixed to 5 or 10%(w/w), were identified as 'irradiated' or 'partially irradiated' or 'un-irradiated'. All samples with un-irradiated pepper up to 20%(w/w) were identified as irradiated'. In the case 5.0 kGy-irradiated paprika were mixed with un-irradiated paprika up to 5%(w/w), all samples were identified as irradiated'. The glow1 curves of samples, including irradiated paprika at 0.2%(w/w) or higher, exhibited a maximum between 150 and 250degC. The results suggest the existence of different critical mixing ratio for the detection of irradiation among each spices. Temperature range for integration of the TL glow intensity were compared between 70-400degC and approximate 150-250degC, and revealed that the latter temperature range was determined based on the measurement of TLD100. Although TL glow ratio in 150-250degC was lower than that of 70-400degC range, identification of irradiation was not affected. Treatment of un-irradiated black pepper and paprika with ultraviolet rays had no effect on the detection of irradiation. (author)

  16. Effect of the irradiation of bacteria upon their survival rate during conventional methods of meat preservation

    International Nuclear Information System (INIS)

    Szczawinska, M.

    1981-01-01

    The purpose of this paper is to define the effect of irradiation upon the survival rate of non-sporing bacteria (Staphylococcus aureus, Salmonella typhimurium, Escherichia coli, Pseudomonas fluorescens) during basic methods of meat preservation. The bacteria were irradiated in broth by X-rays at a dose that destroyed about 90% of the bacteria (D 10 ). The survival rate of unirradiated and irradiated bacteria during cooling and freezing, in solutions of sodium chloride, nitrates and liquid smoke, was defined. The number of microorganisms was determined directly after irradiation as well as 1, 3, 7, 14, 21 and 28 days after irradiation. The effect of irradiation upon heat resistance of the examined species of bacteria was also defined. The microorganisms were heated in broth, at 70 0 C for 1, 2 and 5 minutes. The obtained results were subjected to statistical analysis. On the basis of the research results, a faster dying rate of irradiated populations of S. aureus and E. coli during any type of preservation treatment, the lack of any reaction to irradiation regarding the survival rate of S. typhimurium, and the lack of any effect of irradiation upon the rate of deterioration of P. fluorescens during freezing and storage in a solution with 10% addition of NaCI, were observed. On the other hand, a pronounced effect of irradiation upon the lowering of the heat resistance of the bacteria, as well as delayed growth in other variants of the experiment, was determined. (author)

  17. Mutagenicity of irradiated solutions of nuclei acid bases and nucleosides in Salmonella typhimurium

    International Nuclear Information System (INIS)

    Wilmer, J.; Schubert, J.

    1981-01-01

    Solutions of nucleic acid bases, nucleosides and a nucleotide, saturated with either N 2 , N 2 O or O 2 , were irradiated and tested for mutagenicity towards Salmonella typhimurium, with and without pre-incubation. Irradiated solutions of the nuclei acid bases were all non-mutagenic. Irradiated solutions of the nucleosides showed mutagenicity in S. typhimurium TA100 (pre-incubation assay). Generally, the mutagenicity followed the order: N 2 O > N 2 > O 2 . The results show that the formation of mutagenic radiolytic products is initiated by attack of mainly solutions of the nucleotide thymidine-5'-monophosphate, no mutagenicity could be detected. (orig.)

  18. Nondestructive assay methods for irradiated nuclear fuels

    International Nuclear Information System (INIS)

    Hsue, S.T.; Crane, T.W.; Talbert, W.L. Jr.; Lee, J.C.

    1978-01-01

    This report is a review of the status of nondestructive assay (NDA) methods used to determine burnup and fissile content of irradiated nuclear fuels. The gamma-spectroscopy method measures gamma activities of certain fission products that are proportional to the burnup. Problems associated with this method are migration of the fission products and gamma-ray attenuation through the relatively dense fuel material. The attenuation correction is complicated by generally unknown activity distributions within the assemblies. The neutron methods, which usually involve active interrogation and prompt or delayed signal counting, are designed to assay the fissile content of the spent-fuel elements. Systems to assay highly enriched spent-fuel assemblies have been tested extensively. Feasibility studies have been reported of systems to assay light-water reactor spent-fuel assemblies. The slowing-down spectrometer and neutron resonance absorption methods can distinguish between the uranium and plutonium fissile contents, but they are limited to the assay of individual rods. We have summarized the status of NDA techniques for spent-fuel assay and present some subjects in need of further investigation. Accuracy of the burnup calculations for power reactors is also reviewed

  19. Analysis of products of thymine irradiated by 18O8+ ion beam in N2O saturated aqueous solution

    International Nuclear Information System (INIS)

    Cai Xichen; Wei Zengquan; Li Wenjian; Liang Jianping; Li Qiang

    1999-01-01

    Some methods of capillary gas chromatography, such as GC, GC-MS GC-FT-IR, are used to analyze the products of thymine irradiated by 18 O 8+ ion beam in N 2 O saturated aqueous solution. From the results of GC-MS the molecular weight of products can be determined, and from the results of GC-FT-IR some molecular structure information of products can be obtained. By this way the products, 5,6-Dihydro-thymine, 5-Hydroxyl-5-Methylhydantoin, 5-Hydroxyl-6-Hydro-thymine, 5-Hydro-6-Hydroxyl thymine, 5-Hydroxymethyluracil, Trans-Thymine glycol, Cis-Thymine glycol and dimers are determined without separation of them from samples. Though these products are as same as those products of thymine irradiated by γ rays in N 2 O saturated aqueous solution, the mechanism of thymine irradiated by heavy ion beam in aqueous solution is different from that by γ rays. The main products of thymine irradiated by 18 O 8+ ion beam in N 2 O saturated aqueous solution are hydroxyl adducts at 5-6 band of thymine, while the main products of thymine irradiated by γ ray in N 2 O saturated aqueous solution are dimers of thymine

  20. Supercrystallization of KCl from solution irradiated by soft X-rays

    Science.gov (United States)

    Janavičius, A. J.; Rinkūnas, R.; Purlys, R.

    2016-10-01

    The X-rays influence on KCl crystallization in a saturated water solution has been investigated for the aim of comparing it with previously considered NaCl crystallization. The rate of crystallization has been measured in the drying drop in the solution activated by the irradiation. We have measured the influence of the irradiation time of the solution on the rates of KCl crystallization as well as the beginning of the crystallization processes on drying drops. For a longer irradiation time of the solution early crystallization in the drops occurs. A saturated water solution of KCl was irradiated with the diffractometer DRON-3M (Russian device) and this had a great influence on the two-step processes of crystallization. The ionization of the solution by soft X-rays can produce ions, metastable radicals in water, excited crystals' seeds and vacancies in growing crystals by Auger's effect. The X-rays generate a very fast crystallization in the drying drop.

  1. Development of detection methods for irradiated foods

    International Nuclear Information System (INIS)

    Yang, Jae Seung; Kim, Chong Ki; Lee, Hae Jung; Kim, Kyong Su

    1999-04-01

    To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats. The analysis of DNA damage made on single cells by agarose gel electrophoresis (DNA 'comet assay') can be used to detect irradiated food. All the samples irradiated with over 0.3 kGy were identified to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails, and the tail length of the comets increased with the dose, while unirradiated samples showed no or very short tails. As a result of the above experiment, the DNA 'comet assay' might be applied to the detection of irradiated grains as a simple, low-cost and rapid screening test. When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from leic acid. 1,7 hexadecadiene was the highest amount in irradiated beef, pork and chicken. Eight kinds of hydrocarbons were identified from irradiated chicken, among which 1,7-hexadecadiene and 8-heptadecen were detected as major compounds. The concentration of radiation-induced hydrocarbons was relatively constant during 16 weeks

  2. Development of detection methods for irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Seung; Kim, Chong Ki; Lee, Hae Jung [Korea Atomic Energy Research Insitiute, Taejon (Korea, Republic of); Kim, Kyong Su [Chosun University, Kwangju (Korea, Republic of)

    1999-04-01

    To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats. The analysis of DNA damage made on single cells by agarose gel electrophoresis (DNA 'comet assay') can be used to detect irradiated food. All the samples irradiated with over 0.3 kGy were identified to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails, and the tail length of the comets increased with the dose, while unirradiated samples showed no or very short tails. As a result of the above experiment, the DNA 'comet assay' might be applied to the detection of irradiated grains as a simple, low-cost and rapid screening test. When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from leic acid. 1,7 hexadecadiene was the highest amount in irradiated beef, pork and chicken. Eight kinds of hydrocarbons were identified from irradiated chicken, among which 1,7-hexadecadiene and 8-heptadecen were detected as major compounds. The concentration of radiation-induced hydrocarbons was relatively constant during 16 weeks.

  3. Irradiation effects on electrical properties of DNA solution/Al Schottky diodes

    Science.gov (United States)

    Al-Ta'ii, Hassan Maktuff Jaber; Periasamy, Vengadesh; Iwamoto, Mitsumasa

    2018-04-01

    Deoxyribonucleic acid (DNA) has emerged as one of the most exciting organic material and as such extensively studied as a smart electronic material since the last few decades. DNA molecules have been reported to be utilized in the fabrication of small-scaled sensors and devices. In this current work, the effect of alpha radiation on the electrical properties of an Al/DNA/Al device using DNA solution was studied. It was observed that the carrier transport was governed by electrical interface properties at the Al-DNA interface. Current ( I)-voltage ( V) curves were analyzed by employing the interface limited Schottky current equations, i.e., conventional and Cheung and Cheung's models. Schottky parameters such as ideality factor, barrier height and series resistance were also determined. The extracted barrier height of the Schottky contact before and after radiation was calculated as 0.7845, 0.7877, 0.7948 and 0.7874 eV for the non-radiated, 12, 24 and 36 mGy, respectively. Series resistance of the structure was found to decline with the increase in the irradiation, which was due to the increase in the free radical root effects in charge carriers in the DNA solution. Results pertaining to the electronic profiles obtained in this work may provide a better understanding for the development of precise and rapid radiation sensors using DNA solution.

  4. On the protective action of serotonin according to oxyhaemoglobin at ultraviolet irradiation of the solution mixture

    International Nuclear Information System (INIS)

    Artyukhov, V.G.

    1983-01-01

    The spectral method has been used to show that serotonin in 5x10 - 5 M concentration protects the native (20 deg C) oxyhemoglobin (1.48x10 - 5 M) in the case of ultraviolet irradiation of their mixture at the dose of 12.4x10 4 erg/cm 2 . The protective action of serotonin is also found in respect to modified thermal effects (45 deg C) with irradiated hemoproteid solutions: the degree of photooxidation of oxihemoglobin molecules in the presence of radioprotector is less than in its absence. The conclusion is made that the protective action of radioprotector can be defined by the formation of serotonin-oxyhemoglobin complex

  5. Method for the irradiation of single targets

    International Nuclear Information System (INIS)

    Krimmel, E.; Dullnig, H.

    1977-01-01

    The invention pertains to a system for the irradiation of single targets with particle beams. The targets all have frames around them. The system consists of an automatic advance leading into a high-vacuum chamber, and a positioning element which guides one target after the other into the irradiation position, at right angles to the automatic advance, and back into the automatic advance after irradiation. (GSCH) [de

  6. Development of irradiation rig in HTTR and dosimetry method. I-I type irradiation equipment

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Taiju; Kikuchi, Takayuki [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Miyamoto, Satoshi; Ogura, Kazutomo [Japan Atomic Power Co., Tokyo (Japan)

    2002-12-01

    The High Temperature Engineering Test Reactor (HTTR) is a graphite-moderated, helium gas-cooled test reactor with a maximum power of 30 MW. The HTTR aims not only to establish and upgrade the technological basis for the HTGRs but also to perform the innovative basic research on high temperature engineering with high temperature irradiation fields. It is planned that the HTTR is used to perform various engineering tests such as the safety demonstration test, high temperature test operation and irradiation test with large irradiation fields at high temperatures. This paper describes the design of the I-I type irradiation equipment developed as the first irradiation rig for the HTTR and does the planned dosimetry method at the first irradiation test. It was developed to perform in-pile creep test on a stainless steel with large standard size specimens in the HTTR. It can give great loads on the specimens stably and can control the irradiation temperature precisely. The in-core creep properties on the specimens are measured by newly developed differential transformers and the irradiation condition in the core is monitored by thermocouples and self-powered neutron detectors (SPNDs), continuously. The irradiated neutron fluence is assessed by neutron fluence monitors of small metallic wires after the irradiation. The obtained data at the first irradiation test can strongly be contributed to upgrade the technological basis for the HTGRs, since it is the first direct measurement of the in-core irradiation environments of the HTTR. (author)

  7. Solute segregation and void formation in ion-irradiated vanadium-base alloys

    International Nuclear Information System (INIS)

    Loomis, B.A.; Smith, D.L.

    1985-01-01

    The radiation-induced segregation of solute atoms in the V-15Cr-5Ti alloys was determined after either single- dual-, or helium implantation followed by single-ion irradiation at 725 0 C to radiation damage levels ranging from 103 to 169 dpa. Also, the effect of irradiation temperature (600-750 0 C) on the microstructure in the V-15Cr-5Ti alloy was determined after single-ion irradiation to 200 and 300 dpa. The solute segregation results for the single- and dual-ion irradiated alloy showed that the simultaneous production of irradiation damage and deposition of helium resulted in enhanced depletion of Cr solute and enrichment of Ti, C and S solute in the near-surface layers of irradiated specimens. The observations of the irradiation-damaged microstructures in V-15Cr-5Ti specimens showed an absence of voids for irradiations of the alloy at 600-750 0 C to 200 dpa and at 725 0 C to 300 dpa. The principle effect on the microstructure of these irradiations was to induce the formation of a high density of disc-like precipitates in the vicinity of grain boundaries and intrinsic precipitates and on the dislocation structure. 8 references, 4 figures

  8. Effect of electron beam irradiation on the viscosity of carboxymethylcellulose solution

    International Nuclear Information System (INIS)

    Choi, Jong-il; Lee, Hee-Sub; Kim, Jae-Hun; Lee, Kwang-Won; Chung, Young-Jin; Byun, Myung-Woo; Lee, Ju-Woon

    2008-01-01

    In this study, the effects of an electron beam irradiation on the viscosity of a carboxymethylcellulose (CMC) solution were investigated. The viscosity of the CMC solution was decreased with an increase in the irradiation dose. Interestingly, the extent of the degradation of the CMC was found to decrease with an increase of the CMC concentration in the solution. The change of the average molar mass confirmed the decrease in the viscosity due to the degradation of the polymer. The energy of the electron beam also affected the degradation of the CMC. Lower degradation of the CMC was obtained with a decreasing electron beam energy due to its lower penetration. Addition of vitamin C as a radical scavenger to the solution and an irradiation at -70 deg. C were shown to be moderately effective in preventing a decrease in the viscosity of the solution by irradiation.

  9. Effect of electron beam irradiation on the viscosity of carboxymethylcellulose solution

    Science.gov (United States)

    Choi, Jong-il; Lee, Hee-Sub; Kim, Jae-Hun; Lee, Kwang-Won; Chung, Young-Jin; Byun, Myung-Woo; Lee, Ju-Woon

    2008-12-01

    In this study, the effects of an electron beam irradiation on the viscosity of a carboxymethylcellulose (CMC) solution were investigated. The viscosity of the CMC solution was decreased with an increase in the irradiation dose. Interestingly, the extent of the degradation of the CMC was found to decrease with an increase of the CMC concentration in the solution. The change of the average molar mass confirmed the decrease in the viscosity due to the degradation of the polymer. The energy of the electron beam also affected the degradation of the CMC. Lower degradation of the CMC was obtained with a decreasing electron beam energy due to its lower penetration. Addition of vitamin C as a radical scavenger to the solution and an irradiation at -70 °C were shown to be moderately effective in preventing a decrease in the viscosity of the solution by irradiation.

  10. Effect of electron beam irradiation on the viscosity of carboxymethylcellulose solution

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong-il [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongeup 580-185 (Korea, Republic of); Lee, Hee-Sub [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongeup 580-185 (Korea, Republic of); Department of Food and Nutrition, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Kim, Jae-Hun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongeup 580-185 (Korea, Republic of); Lee, Kwang-Won [Department of Orthopaedic Surgery, Eulji University School of Medicine, Daejeon 302-799 (Korea, Republic of); Chung, Young-Jin [Department of Food and Nutrition, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Byun, Myung-Woo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongeup 580-185 (Korea, Republic of); Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongeup 580-185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

    2008-12-15

    In this study, the effects of an electron beam irradiation on the viscosity of a carboxymethylcellulose (CMC) solution were investigated. The viscosity of the CMC solution was decreased with an increase in the irradiation dose. Interestingly, the extent of the degradation of the CMC was found to decrease with an increase of the CMC concentration in the solution. The change of the average molar mass confirmed the decrease in the viscosity due to the degradation of the polymer. The energy of the electron beam also affected the degradation of the CMC. Lower degradation of the CMC was obtained with a decreasing electron beam energy due to its lower penetration. Addition of vitamin C as a radical scavenger to the solution and an irradiation at -70 deg. C were shown to be moderately effective in preventing a decrease in the viscosity of the solution by irradiation.

  11. Suitability of the thermoluminescence method for detection of irradiated foods

    International Nuclear Information System (INIS)

    Pinnioja, S.

    1993-01-01

    Irradiated foods can be detected by thermoluminescence (TL) of contaminating minerals. Altogether about 300 lots of herbs, spices, berries, mushrooms and seafood were studied by the TL method. Irradiated herbs and spices were easily differentiated from unirradiated ones two years after irradiation of a 10 kGy dose. The mineral composition of seafood was variable; and while calcite was suitable for the TL analysis, aragonite and smectite gave unreliable results. Control analyses during two years confirmed the reliability of TL method. (author)

  12. Formation of fine solid particles from aqueous solutions of sodium chloropalladate by gamma-ray irradiation

    International Nuclear Information System (INIS)

    Hatada, Motoyoshi; Fujita, Iwao; Korekawa, Kei-ichi.

    1994-10-01

    Studies have been carried out on the radiation chemical formation of palladium fine particles in argon saturated aqueous solutions of sodium chloropalladate without organic stabilizer. The solutions were irradiated with gamma-rays from a cobalt gamma-ray source and the irradiated solutions were subjected to the dynamic light scattering analysis for the particle diameter measurements, and to the UV-visible optical absorption spectroscopy for the measurements of turbidity (absorption at 700 nm) and remaining chloropalladate ion concentrations in the solution. In the solution of pH = 1.95 by HCl, the turbidity increased after the irradiation and then decreased with time. The concentration of remaining palladate ion in the solution decreased by the irradiation, but it gradually increased with time after the irradiation. These phenomena were qualitatively explained by the reaction scheme in that a precursor to the solid particles still exists in the solution after the irradiation was terminated, and that intermediates including the precursor reacted with chloride ion to re-form chloropalladate ions. The average diameter of the particles after the irradiation was ca. 20 nm and it increased with time to 40 nm at 2.75 kGy, and to 80 nm at 8.25 kGy absorption of radiation. The solution of pH = 0.65 by HCl was found to give lower yields of particles than those observed for the solution of pH = 1.95, and to give the particles of diameters about 150-200 nm. In the solution containing HClO 4 instead of HCl, palladium particles were also formed by the irradiation, whereas no backward reaction after the irradiation was observed due to the low concentration of chloride ion in the solution. The average diameter of the particles after the irradiation was about 300 nm and increased with time after the irradiation to a final values which was found to depend on pH of the solution and dose. (author)

  13. Characterization of aqueous solution of cresol red as food irradiation dosimeter

    International Nuclear Information System (INIS)

    Khan, H.M.; Tabassum, S.; Wahid, M.S.

    2009-01-01

    Dilute aqueous solution of cresol red has been evaluated spectrophotometrically as possible gamma rays dosimeter. A 0.10 mM solution of cresol red was irradiated by gamma rays using a cobalt-60 radiation source. The absorbance spectra of the unirradiated and irradiated solutions were recorded using double beam scanning spectrophotometer. The absorbance of the solution before and after irradiation was measured at 434 nm (λ max ) as well as at other wavelengths (415, 448 and 470 nm). Various parameters, such as Absorbance (A), ΔA, %A, -log A and log A o /A i were plotted against radiation dose, in order to check the response of cresol red solution and its possible use as chemical dosimeter. The response plots of A, ΔA, and %A versus absorbed dose showed that the solution can be used as a radiation dosimeter in a dose range up to 0.82 kGy. Using response plots of -log A and log A o /A i , the useful dose range can be extended up to 1.65 kGy; which are useful dose ranges for food irradiation applications. Stability studies of cresol red solution at different light and temperature conditions for pre- and post-irradiated storage of the dosimetric solutions suggested that aqueous solution of cresol red is highly stable in dark, under fluorescence light and at room temperature up to 150 days (author)

  14. Characterization of aqueous solution of cresol red as food irradiation dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Khan, H M; Tabassum, S; Wahid, M S [Peshawar University, Peshawar (Pakistan). Radiation Chemistry Laboratory, National Centre of Excellence in Physical Chemistry

    2009-06-15

    Dilute aqueous solution of cresol red has been evaluated spectrophotometrically as possible gamma rays dosimeter. A 0.10 mM solution of cresol red was irradiated by gamma rays using a cobalt-60 radiation source. The absorbance spectra of the unirradiated and irradiated solutions were recorded using double beam scanning spectrophotometer. The absorbance of the solution before and after irradiation was measured at 434 nm ({lambda}{sub max}) as well as at other wavelengths (415, 448 and 470 nm). Various parameters, such as Absorbance (A), {delta}A, %A, -log A and log A{sub o}/A{sub i} were plotted against radiation dose, in order to check the response of cresol red solution and its possible use as chemical dosimeter. The response plots of A, {delta}A, and %A versus absorbed dose showed that the solution can be used as a radiation dosimeter in a dose range up to 0.82 kGy. Using response plots of -log A and log A{sub o}/A{sub i}, the useful dose range can be extended up to 1.65 kGy; which are useful dose ranges for food irradiation applications. Stability studies of cresol red solution at different light and temperature conditions for pre- and post-irradiated storage of the dosimetric solutions suggested that aqueous solution of cresol red is highly stable in dark, under fluorescence light and at room temperature up to 150 days (author)

  15. Detection of irradiated meats by hydrocarbon method

    International Nuclear Information System (INIS)

    Goto, Michiko; Miyakawa, Hiroyuki; Fujinuma, Kenji; Ozawa, Hideki

    2005-01-01

    Meats, for example, lamb, razorback, wild duck and turkey were irradiated by gamma ray, and the amounts of hydrocarbons formed from fatty acids were measured. Since C 20:0 was found from wild duck and turkey. C 1-18:1 was recommended for internal standard. Good correlation was found between the amount of hydrocarbons and the doses of gamma irradiation. This study shows that such hydrocarbons induced after radiation procedure as C 1,7-16:2 , C 8-17:1 , C 1-14:1 , and C 15:0 may make it possible to detect irradiated lamb, razorback, wild duck and turkey. (author)

  16. Kinetics of phenol degradation in water solutions under gamma-irradiation

    International Nuclear Information System (INIS)

    Guliyeva, U.A.; Gurbanov, M.A.; Abdullayev, E.T.

    2014-01-01

    Full text : In this work the chemical oxygen demand and change of phenol concentration at the radiolysis of aqueous solutions of phenol was studied. Irradiation conducted under gamma-irradiation of 60Co at static conditions and at room temperature. The main component is water, therefore the radiolysis process of water plays an important role in radiolytic degradation of phenol

  17. Formation of nanoparticles and nanorods via UV irradiation of AgNO3 solutions

    International Nuclear Information System (INIS)

    Szymanska-Chargot, M.; Gruszecka, A.; Smolira, A.; Bederski, K.; Gluch, K.; Cytawa, J.; Michalak, L.

    2009-01-01

    The synthesis of silver nanoparticles via UV irradiation of AgNO 3 solutions was controlled by using UV-vis absorption spectra and TEM (transmission electron microscope) images. The UV-vis absorption method is good enough for the general control of synthesis process, and TEM images give us information about size of formed species. For investigated solutions of silver nitrate in ethanol and water, we observed formation of large nanoparticles (size about 100 nm) and nanorods (100 nm in length). Moreover, there was effort to confirm evidence of formation of these particles by using TOF mass spectrometer. Due to laser desorption/ionization process there is only evidence of small silver nanoparticles Ag x , x ≤ 4 (clusters), and variety of silver compounds Ag x N y O z (x ≤ 5, y ≤ 2, z ≤ 3).

  18. Development of detection methods for irradiated foods

    International Nuclear Information System (INIS)

    Yang, Jae Seung; Nam, Hye Seon; Oh, Kyong Nam; Woo, Si Ho; Kim, Kyeung Eun; Yi, Sang Duk; Park, Jun Young; Kim, Kyong Su; Hwang, Keum Taek

    2000-04-01

    In 1999, we have been studied (1) on the detection of irradiated foods by ESR spectroscopy, by thermoluminescence, and by viscometry for physical measurements, (2) on the detection of hydrocarbons and 2-alkylcyclobutanones derived from fatty foods by GC/MS for chemical measurements, (3) on the screening and detection of irradiated foods by Comet assay and immunochemical (ELISA) technique for biological or biochemical measurements

  19. Development of detection methods for irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Seung; Nam, Hye Seon; Oh, Kyong Nam; Woo, Si Ho; Kim, Kyeung Eun; Yi, Sang Duk; Park, Jun Young; Kim, Kyong Su; Hwang, Keum Taek

    2000-04-01

    In 1999, we have been studied (1) on the detection of irradiated foods by ESR spectroscopy, by thermoluminescence, and by viscometry for physical measurements, (2) on the detection of hydrocarbons and 2-alkylcyclobutanones derived from fatty foods by GC/MS for chemical measurements, (3) on the screening and detection of irradiated foods by Comet assay and immunochemical (ELISA) technique for biological or biochemical measurements.

  20. Irradiation as an effective method of food conservation

    International Nuclear Information System (INIS)

    Stachowicz, W.

    1994-01-01

    Irradiation as an effective method for food preservation has been introduced. The worldwide history of radiation methods development has been shown. The state of art of international legislation connected with food irradiation and licensing of that technology in different countries has been reviewed. The list of food products commonly accepted for radiation conservation has also been performed

  1. Irradiation creep of solution annealed and coldworked 316 stainless steel

    International Nuclear Information System (INIS)

    Boutard, J.L.; Carteret, Y.; Cauvin, R.; Guerin, Y.; Maillard, A.

    1983-04-01

    Because SA and CW 316 stainless steels were used as standard cladding material, a lot of plastic strain data is now avalaible. Most of it is published and analyzed in term of an irradiation creep modulus A defined as the ratio of the equivalent plastic strain to the product of the equivalent stress by the dose. In fact the experimental data and the theoretical analysis of the in-pile deformation mechanisms show a more complicated situation. The purpose of this paper is to reanalyze our results taking into account this situation. This approach is divided in two parts: 1) the high temperature range (T>=450 0 C) where data come from irradiated pins; 2) the low temperature range (T 0 C) where results come from pressurized tubes irradiated in experimental rigs

  2. Development of detection methods for irradiated foods - Detection method for radiolytic products of irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyong Su; Kim, Sun Min; Park, Eun Ryong; Lee, Hae Jung; Kim, Eun Ah; Jo, Jung Ok [Chosun University, Kwangju (Korea)

    1999-04-01

    Meat (beef, pork, chicken) and nut (sesame, perilla, black sesame, peanut) were irradiated with /sup 60/Co gamma-ray. A process to detect radiation-induced hydrocarbons and 2-alkylcyclobutanones includes the extraction of fat from meat and nut, separation of hydrocarbons and 2-alkylcyclobutanones with a florisil column and identification of GC/MS methods. Concentrations of the produced hydrocarbons and 2-alkylcyclobutanones tended to increase linearly with the dose levels of irradiation in beef, pork and chicken, while concentrations of radiation-induced hydrocarbons were different individually at the same dose level. In meat, hydrocarbons and 2-alkylcyclobutanones originated from oleic acid were found in a large amount. The concentrations of radiation-induced hydrocarbons were relatively constant during 16 weeks. In nut, hydrocarbons originated from oleic acid and linoleic acid were the major compounds whereas results of perilla was similar to meat. Radiation-induced hydrocarbons were increased linearly with the irradiation dose and remarkably detected at 0.5 kGy and over. 44 refs., 30 figs., 14 tabs. (Author)

  3. Bone-like hydroxyapatite precipitated from 10×SBF-like solution by microwave irradiation

    International Nuclear Information System (INIS)

    Tolga Demirtaş, T.; Kaynak, Gökçe; Gümüşderelioğlu, Menemşe

    2015-01-01

    Microwave-assisted methods have been frequently used in many processes owing to their numerous advantages such as performing fast, efficient and homogenous processes and reducing side reactions. In view of these benefits, in this study it was purposed to produce bone-like hydroxyapatite (HA) by inducing biomimetic process with microwave-irradiation. This is why, concentrated body fluid (SBF) i.e. 10×SBF-like solution was used and it was precipitated in different microwave powers i.e. 90 W, 360 W, 600 W, and 1200 W and in different exposure times. For comparison, precipitation process was also carried out at room temperature for 6 h and at 80 °C for 1 h. The obtained HA structures were characterized by appropriate instrumental techniques. As a result, microwave-induced precipitation at 600 W for 9 times 30 s was determined as the optimum condition for the production of HA which has similar properties to the cortical bone. At this condition, B-type HA with 9.22% (wt.) carbonate content, 1.61 Ca/P molar ratio and amorphous structure was obtained easily, rapidly and efficiently. So, this is the first time microwave technology has been used to precipitate HA from SBF solution. - Highlights: • Simple, rapid and efficient method was developed to produce bone-like HA. • Microwave radiation and biomimetic approach via 10×SBF-like solution were combined. • Microwave irradiation at 600 W for 9 × 30 s was determined as the optimum condition. • B-type HA (carbonate content: 9.22%; 1.61 Ca/P:1.61; amorph) was produced. • This method may be employed for the effective HA coating of 3D bone scaffolds

  4. Bone-like hydroxyapatite precipitated from 10×SBF-like solution by microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Tolga Demirtaş, T.; Kaynak, Gökçe [Bioengineering Engineering Department, Hacettepe University, 06800 Beytepe, Ankara (Turkey); Gümüşderelioğlu, Menemşe, E-mail: menemse@hacettepe.edu.tr [Bioengineering Engineering Department, Hacettepe University, 06800 Beytepe, Ankara (Turkey); Chemical Engineering Department, Hacettepe University, 06800 Beytepe, Ankara (Turkey)

    2015-04-01

    Microwave-assisted methods have been frequently used in many processes owing to their numerous advantages such as performing fast, efficient and homogenous processes and reducing side reactions. In view of these benefits, in this study it was purposed to produce bone-like hydroxyapatite (HA) by inducing biomimetic process with microwave-irradiation. This is why, concentrated body fluid (SBF) i.e. 10×SBF-like solution was used and it was precipitated in different microwave powers i.e. 90 W, 360 W, 600 W, and 1200 W and in different exposure times. For comparison, precipitation process was also carried out at room temperature for 6 h and at 80 °C for 1 h. The obtained HA structures were characterized by appropriate instrumental techniques. As a result, microwave-induced precipitation at 600 W for 9 times 30 s was determined as the optimum condition for the production of HA which has similar properties to the cortical bone. At this condition, B-type HA with 9.22% (wt.) carbonate content, 1.61 Ca/P molar ratio and amorphous structure was obtained easily, rapidly and efficiently. So, this is the first time microwave technology has been used to precipitate HA from SBF solution. - Highlights: • Simple, rapid and efficient method was developed to produce bone-like HA. • Microwave radiation and biomimetic approach via 10×SBF-like solution were combined. • Microwave irradiation at 600 W for 9 × 30 s was determined as the optimum condition. • B-type HA (carbonate content: 9.22%; 1.61 Ca/P:1.61; amorph) was produced. • This method may be employed for the effective HA coating of 3D bone scaffolds.

  5. Method of continuously regenerating decontaminating electrolytic solution

    International Nuclear Information System (INIS)

    Sasaki, Takashi; Kobayashi, Toshio; Wada, Koichi.

    1985-01-01

    Purpose: To continuously recover radioactive metal ions from the electrolytic solution used for the electrolytic decontamination of radioactive equipment and increased with the radioactive dose, as well as regenerate the electrolytic solution to a high concentration acid. Method: A liquid in an auxiliary tank is recycled to a cathode chamber containing water of an electro depositing regeneration tank to render pH = 2 by way of a pH controller and a pH electrode. The electrolytic solution in an electrolytic decontaminating tank is introduced by way of an injection pump to an auxiliary tank and, interlocking therewith, a regenerating solution is introduced from a regenerating solution extracting pump by way of a extraction pipeway to an electrolytic decontaminating tank. Meanwhile, electric current is supplied to the electrode to deposit radioactive metal ions dissolved in the cathode chamber on the capturing electrode. While on the other hand, anions are transferred by way of a partition wall to an anode chamber to regenerate the electrolytic solution to high concentration acid solution. While on the other hand, water is supplied by way of an electromagnetic valve interlocking with the level meter to maintain the level meter constant. This can decrease the generation of the liquid wastes and also reduce the amount of the radioactive secondary wastes. (Horiuchi, T.)

  6. Detection of irradiated food - methods and routine applications

    International Nuclear Information System (INIS)

    Schreiber, G.A.; Helle, N.; Boegl, K.W.

    1993-01-01

    Irradiation of food for the purposes of extension of shelf life, control of microbial load, reduction of pathogenic microorganisms and disinfection is regarded by many consumers with suspicion. One reason is the lack of methods within food-controlling laboratories which can detect irradiation treatment and which are applied to control correct labelling. This review describes the potential of various methods to reveal irradiation treatment. Special emphasis is given to the three most successful methods, thermoluminescence, electron spin resonance spectroscopy and detection of volatiles. The possibilities and limitations of applying the methods in routine control are discussed. (author)

  7. Method of lines solution of Richards` equation

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, C.T.; Miller, C.T.; Tocci, M.D.

    1996-12-31

    We consider the method of lines solution of Richard`s equation, which models flow through porous media, as an example of a situation in which the method can give incorrect results because of premature termination of the nonlinear corrector iteration. This premature termination arises when the solution has a sharp moving front and the Jacobian is ill-conditioned. While this problem can be solved by tightening the tolerances provided to the ODE or DAE solver used for the temporal integration, it is more efficient to modify the termination criteria of the nonlinear solver and/or recompute the Jacobian more frequently. In this paper we continue previous work on this topic by analyzing the modifications in more detail and giving a strategy on how the modifications can be turned on and off in response to changes in the character of the solution.

  8. The digestibility of gamma-irradiated bovine serum albumin solution with thermolysin

    International Nuclear Information System (INIS)

    Hattori, Yukihiko

    1981-01-01

    Samples of bovine serum albumin (BSA) (fatty acid free, fraction V, purchased from Miles Laboratories Inc.) solution (in triply distilled water) were irradiated with 60 Co γ-rays in Pyrex tubes in the presence of air at room temperature. Taking the practical conditions of food irradiation into consideration, the concentration of BSA solution ranged from 0.6 to 9.6%, and the dose ranged from 5 to 15 kGy. Irradiated BSA solutions were subjected to the assay of proteolytic digestibility with thermolysin. The result indicates that all irradiated samples had larger digestibility with thermolysin than unirradiated control. Within the dose range of the experiment, the largest digestibility values for the irradiated samples of 0.6, 1.2, 2.4, 4.8 and 9.6% were 2.7, 2.5, 2.5, 2.3, and 1.9 times as large as that of unirradiated control, respectively. In the case of 0.6% solution the digestibility showed its maximum at 5 kGy, and at the higher doses (10 and 15 kGy) it decreased linearly. The irradiated BSA solutions of 1.2% or higher concentrations did not reveal such decrease in the digestibility. The results of analyses of amino acid composition and ultracentrifugal sedimentation pattern suggest that the decrease in the digestibility in the case of 0.6% solution can be attributed to the modification of amino acid residues, crosslinking and aggregation of BSA molecules. Furthermore, it is mentioned that the digestibility with thermolysin will be a possible measure for the denaturation of water containing protein irradiated with practical dose for the food irradiation. (J.P.N.)

  9. Analytical methods to identify irradiated food

    International Nuclear Information System (INIS)

    Helle, N.; Schreiber, G.A.; Boegl, K.W.

    1992-01-01

    During the last years, three promising techniques for the identification of irradiated food were developed: - Studies of luminescence, mainly thermoluminescence measurements, of food containing mineral impurities like spices, dried vegetables: and fresh fuit and vegetables. This technique can probably be applied also to food with crystalline components like shells or bones. - Gaschromatographic/mass-spectrometric investigation of radiation-induced lipid changes. - Electron-spin-resonance measurements of dried products or of products containing dry components like bones, fish bones, shells or seeds. The thermoluminescence technique has been routinely applied for more than one year by several German Food Inspection Laboratories. The results suggest that there are scarcely any irradiated spices and dried vegetables in the German market. Gaschromatography/mass spectrometry of lipid components and electron-spin-resonance spectroscopy will be established in routine food inspections in Germany in the next two years. Further possibilities to identify irradiated food are the analysis of specific changes in amino acids, DNA and carbohydrates. Radiation-induced viscosity changes, and changes in electric properties (impedance) may be helpful in identifiying at least some irradiated products. Also microbiological and biological techniques as e.g. microbial flora shift or embryo development tests in citrus fruit have been considered. All activities concerning the development of identification techniques are now coordinated by the European Communities and by IAEA. (orig.) [de

  10. Algebraic methods for solution of polyhedra

    Energy Technology Data Exchange (ETDEWEB)

    Sabitov, Idzhad Kh [M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2011-06-30

    By analogy with the solution of triangles, the solution of polyhedra means a theory and methods for calculating some geometric parameters of polyhedra in terms of other parameters of them. The main content of this paper is a survey of results on calculating the volumes of polyhedra in terms of their metrics and combinatorial structures. It turns out that a far-reaching generalization of Heron's formula for the area of a triangle to the volumes of polyhedra is possible, and it underlies the proof of the conjecture that the volume of a deformed flexible polyhedron remains constant. Bibliography: 110 titles.

  11. Stability of carotenoids toward UV-irradiation in hexane solution

    Directory of Open Access Journals (Sweden)

    DRAGAN CVETKOVIC

    2008-01-01

    Full Text Available The stabilities of four selected carotenoids dissolved in hexane, two carotenes and two xanthophylls, toward UV-irradiation of three different ranges (UV-A, UV-B and UV-C were studied in this work. The carotenoids underwent bleaching via a probable free radical mediated mechanism following first-order kinetics. The bleaching rates were highly dependent on the input of the involved photons and, although not consistently, on the chemical structures of the investigated compounds. For the two xanthophylls, a possible role of oxygen associated with their bleaching cannot be neglected.

  12. Development and Establishment of Detection Method of Irradiated Foods

    International Nuclear Information System (INIS)

    Byun, Myung Woo; Lee, Ju Woon; Kim, Dong Ho; Jo, Cheo Run; Kim, Jang Ho; Kim, Kyong Su

    2004-12-01

    The present project was related to the development and establishment of the detection techniques for the safety management of gamma-irradiated food and particularly conducted for the establishment of standard detection method for gamma-irradiated dried spices and raw materials, dried meat and fish powder for processed foods, bean paste powder, red pepper paste powder, soy sauce powder, and starch for flavoring ingredients described in 3, 6, 7 section of Korean Food Standard. Since the approvement of gamma-irradiated food items will be enlarged due to the international tendency for gamma-irradiated food, it was concluded that the establishment of detailed detection methods for each food group is not efficient for the enactment and enforcement of related regulations. For this reason, in order to establish the standard detection method, a detection system for gamma-irradiated food suitable for domestic operation was studied using comparative analysis of domestic and foreign research data classified by items and methods and European Standard as a reference. According to the comparative analyses of domestic and foreign research data and regulations of detection for gamma-irradiated food, it was concluded to be desirable that the optimal detection method should be decided after principal detection tests such as physical, chemical, and biological detection methods are established as standard methods and that the specific descriptions such as pre-treatment of raw materials, test methods, and the evaluation of results should be separately prescribed

  13. Development and Establishment of Detection Method of Irradiated Foods

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Myung Woo; Lee, Ju Woon; Kim, Dong Ho; Jo, Cheo Run; Kim, Jang Ho; Kim, Kyong Su

    2004-12-15

    The present project was related to the development and establishment of the detection techniques for the safety management of gamma-irradiated food and particularly conducted for the establishment of standard detection method for gamma-irradiated dried spices and raw materials, dried meat and fish powder for processed foods, bean paste powder, red pepper paste powder, soy sauce powder, and starch for flavoring ingredients described in 3, 6, 7 section of Korean Food Standard. Since the approvement of gamma-irradiated food items will be enlarged due to the international tendency for gamma-irradiated food, it was concluded that the establishment of detailed detection methods for each food group is not efficient for the enactment and enforcement of related regulations. For this reason, in order to establish the standard detection method, a detection system for gamma-irradiated food suitable for domestic operation was studied using comparative analysis of domestic and foreign research data classified by items and methods and European Standard as a reference. According to the comparative analyses of domestic and foreign research data and regulations of detection for gamma-irradiated food, it was concluded to be desirable that the optimal detection method should be decided after principal detection tests such as physical, chemical, and biological detection methods are established as standard methods and that the specific descriptions such as pre-treatment of raw materials, test methods, and the evaluation of results should be separately prescribed.

  14. Effects of additives on 2,4,6-trinitrotoluene (TNT) removal and its mineralization in aqueous solution by gamma irradiation

    International Nuclear Information System (INIS)

    Lee, Byungjin; Jeong, Seung-Woo

    2009-01-01

    The effects of additives (i.e., methanol, EDTA, mannitol, thiourea, nitrous oxide, oxygen and ozone) on gamma irradiation of 2,4,6-trinitrotoluene (TNT) were investigated to elucidate the initial reaction mechanism of TNT degradation and suggest an practical method for complete by-product removal. All additives, except thiourea, significantly increased the TNT removal efficiency by gamma irradiation. The overall results of the additive experiments implied that the TNT decomposition would be initiated by ·OH, e aq - , and HO 2 ·/O 2 · - , and also implied that ·H did not have any direct effect on the TNT decomposition. Additions of methanol and nitrous oxide were more effective in TNT removal than the other additives, achieving complete removal of TNT at doses below 20 kGy. Total organic carbon (TOC) of the irradiated solution was analyzed to evaluate the degree of TNT mineralization under the additive conditions. TOC under the nitrous oxide addition was removed rapidly, and complete TNT mineralization was thus achieved at 50 kGy. Methanol addition was very effective in the TNT removal, but it was not effective in reduction in TOC. Trinitrobenzene (TNB), oxalic acid and glyoxalic acid were detected as radiolytic organic by-products, while ammonia and nitrate were detected as radiolytic inorganic by-products. The most efficient TNT removal and its mineralization by gamma irradiation would be achieved by supersaturating the solution with nitrous oxide before irradiation.

  15. A review of irradiation induced re-solution in oxide fuels

    International Nuclear Information System (INIS)

    Turnbull, J.A.

    1980-01-01

    The paper reviews the existing experimental evidence for irradiation induced re-solution and also possible explanations for the mechanism. The importance of re-solution is considered with regard to intragranular bubbles and the accumulation of gas on grain boundaries. It is concluded that re-solution is most effective at low temperatures and could account for the present concern over gas release in high burn-up water reactor fuel assemblies. (author)

  16. Damage induced by hydroxyl radicals generated in the hydration layer of γ-irradiated frozen aqueous solution of DNA

    International Nuclear Information System (INIS)

    Ohshima, Hideki; Matsuda, Akira; Kuwabara, Mikinori; Iida, Yoshiharu.

    1996-01-01

    Aqueous DNA solutions with or without the spin trap α-phenyl-N-tert-butylnitrone (PBN) were exposed to γ-rays at 77 K. After thawing the solutions, three experiments were carried out to confirm the generation of OH radicals in the hydration layer of DNA and to examine whether they act as an inducer of DNA strand breaks and base alterations. Observation with the EZR-spin tapping method showed ESR signals from PBN-OH adducts in the solution containing PBN and DNA, but there were few signals in the solution containing PBN alone, suggesting that reactive OH radicals were produced in the hydration layer of γ-irradiated DNA and were effectively scavenged by PBN, and that unreactive OH radicals were produced in the free water layer of γ-irradiated DNA. Agarose gel electrophoresis of DNA proved that PBN had no effect on the formation of strand breaks, whereas examination with the high-performance liquid chromatography-eloctrochemical detection (HPLC-ECD) method showed that PBN suppressed the formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG). From these results it was concluded that OH radicals generated in the hydration layer of γ-irradiated DNA did not induce DNA strand breaks but induced base alterations. (author)

  17. Development of a microbiological irradiation detection method for spices

    International Nuclear Information System (INIS)

    Koshikawa, T.; Takekawa, T.; Miyahara, M.

    2009-01-01

    In order to judge whether certain spices had been irradiated or not, we examined the possibility of developing a method based on the microbiological examination of spices. We used the total bacteria count in conjunction with the ratio of B. megaterium and B. cereus to the total bacteria count. The examination results of 6 kinds of spices with or without irradiation (black pepper, white pepper, coriander, paprika, ginger and turmeric), were as follows. Total bacteria counts over 10E5 CFU/g indicated that the samples were 'unirradiated'. When the total bacteria count was less than 10E5 CFU/g, and the ratio of B. megaterium and B. cereus to the total count was more than 30%, a history of irradiation of the samples was indicated. When ratios of B. megaterium and B. cereus were less than 30% and the total bacteria count was also less than 10E5 CFU/g, 'uncertainty' of irradiation was indicated. In this case, it would be possible to confirm whether spices were 'unirradiated' or 'irradiated' by using another detection method. This detection method was applicable to other spices except for paprika. The samples judged as 'irradiated' by using this detection method, surely proved to have a history of irradiation treatment

  18. Method for mounting laser fusion targets for irradiation

    Science.gov (United States)

    Fries, R. Jay; Farnum, Eugene H.; McCall, Gene H.

    1977-07-26

    Methods for preparing laser fusion targets of the ball-and-disk type are disclosed. Such targets are suitable for irradiation with one or two laser beams to produce the requisite uniform compression of the fuel material.

  19. Dynamic rheology behavior of electron beam-irradiated cellulose pulp/NMMO solution

    International Nuclear Information System (INIS)

    Zhou Ruimin; Deng Bangjun; Hao Xufeng; Zhou Fei; Wu Xinfeng; Chen Yongkang

    2008-01-01

    The rheological behavior of irradiated cellulose pulp solution by electron beam was investigated. Storage modulus G', loss modulus G'', the dependence of complex viscosity η* and frequency ω of cellulose solutions were measured by DSR-200 Rheometer (Rheometrics co., USA). The molecular weight of irradiated cellulose was measured via the intrinsic viscosity measurement using an Ubbelohde capillary viscometer. The crystalline structure was studied by FTIR Spectroscopy. The results congruously showed that the molecular weight of pulp cellulose decrease and the molecular weight distribution of cellulose become narrow with increase in the irradiation dose. Moreover, the crystalline structure of the cellulose was destroyed, the force of the snarl between the cellulose molecules weakens and the accessibility of pulp spinning is improved. The study supplies some useful data for spinnability of irradiated cellulose and technical data to the filature industry

  20. EPR study of the production of OH radicals in aqueous solutions of uranium irradiated by ultraviolet light

    Directory of Open Access Journals (Sweden)

    MARKO DAKOVIĆ

    2009-06-01

    Full Text Available The aim of the study was to establish whether hydroxyl radicals (•OH were produced in UV-irradiated aqueous solutions of uranyl salts. The production of •OH was studied in uranyl acetate and nitrate solutions by an EPR spin trap method over a wide pH range, with variation of the uranium concentrations. The production of •OH in uranyl solutions irradiated with UV was unequivocally demonstrated for the first time using the EPR spin-trapping method. The production of •OH can be connected to speciation of uranium species in aqueous solutions, showing a complex dependence on the solution pH. When compared with the results of radiative de-excitation of excited uranyl (*UO22+ by the quenching of its fluorescence, the present results indicate that the generation of hydroxyl radicals plays a major role in the fluorescence decay of *UO22+. The role of the presence of carbonates and counter ions pertinent to environmental conditions in biological systems on the production of hydroxyl radicals was also assessed in an attempt to reveal the mechanism of *UO22+ de-excitation. Various mechanisms, including •OH production, are inferred but the main point is that the generation of •OH in uranium containing solutions must be considered when assessing uranium toxicity.

  1. Method for selective irradiation of thyristors

    International Nuclear Information System (INIS)

    Sheng, W.W.; Sun, Y.S.E.; Tefft, E.G.

    1979-01-01

    The commutating dv/dt capability of the triac is improved without affecting the gate carrier flow. This is achieved by masking the two current-carring regions and the hole region by means of a solder with high lead contont and irradiation with electrons in the range of 400 keV and 12 MeV and a dose of 10 12 up to 10 15 electrons/cm 2 . The electrons cause lattice defects in the intermediate boundary regions. (DG) [de

  2. Lactose and sucrose aqueous solutions for high-dose dosimetry with 10-MeV electron beam irradiation

    International Nuclear Information System (INIS)

    Amraei, R.; Kheirkhah, M.; Raisali, G.

    2012-01-01

    In the present study, dosimetric characterisation of aqueous solutions of lactose and sucrose was analysed by UV spectrometry following irradiation using 10-MeV electron beam at doses between 0.5 and 10.5 kGy. As a dosimetric index, absorbance is selected at 256 and 264 nm for lactose and sucrose aqueous solutions, respectively. The intensity of absorbance for irradiated solutions depends on the pre-irradiation concentration of lactose and sucrose. The post-irradiation stability of both solutions was investigated at room temperature for a measurement period of 22 d. (authors)

  3. Current status of the EPR method to detect irradiated food

    International Nuclear Information System (INIS)

    Desrosiers, M.F.

    1996-01-01

    This review gives a brief outline of the principles of the EPR detection method for irradiated foods by food type. For each food type, the scope, limitations and status of the method are given. The extensive reference list aims to include all which define the method, as well as some rarely cited works of historical importance. (author)

  4. Radical pair formation in γ-irradiated 2-methyltetrahydrofuran rigid solutions of polynitrobenzenes

    International Nuclear Information System (INIS)

    Konishi, S.; Hoshino, M.; Imamura, M.

    1981-01-01

    The γ-irradiated MTHF (2-methyltetrahydrofuran) rigid solutions of mDNB (m-dinitrobenzene) and sTNB (s-trinitrobenzene) showed at 77 K ESR spectra characteristic of triplet species in addition to the spectra of doublet species, whereas no triplet ESR spectra were observed for the mononitrobenzene and o- and p-di-nitrobenzene solutions. The distances of the unpaired spins evaluated from the observed fine structure constants by using a point-dipole approximation are 4.3 and 4.6 A for the mDNB solution and 3.9 and 4.7 A for the sTNB solution. The detection of only the solute anion radicals by the optical absorption spectra of the irradiated solutions and the difference of the rate of formation for the triplet species and the solute anion strongly suggest that the triplet species are ascribed to the solute anion-solvent radical pairs. Such radical pairs are most likely to be formed through the migration of a MTHF cation radical, i.e., so-called hole migration, to a specific site between the two nitro groups on the meta positions of a solute anion followed by the production of a stable solvent radical, which is paired with the solute anion

  5. Chemical deposition methods using supercritical fluid solutions

    Science.gov (United States)

    Sievers, Robert E.; Hansen, Brian N.

    1990-01-01

    A method for depositing a film of a desired material on a substrate comprises dissolving at least one reagent in a supercritical fluid comprising at least one solvent. Either the reagent is capable of reacting with or is a precursor of a compound capable of reacting with the solvent to form the desired product, or at least one additional reagent is included in the supercritical solution and is capable of reacting with or is a precursor of a compound capable of reacting with the first reagent or with a compound derived from the first reagent to form the desired material. The supercritical solution is expanded to produce a vapor or aerosol and a chemical reaction is induced in the vapor or aerosol so that a film of the desired material resulting from the chemical reaction is deposited on the substrate surface. In an alternate embodiment, the supercritical solution containing at least one reagent is expanded to produce a vapor or aerosol which is then mixed with a gas containing at least one additional reagent. A chemical reaction is induced in the resulting mixture so that a film of the desired material is deposited.

  6. The mechanism of solute-enriched clusters formation in neutron-irradiated pressure vessel steels: The case of Fe-Cu model alloys

    Energy Technology Data Exchange (ETDEWEB)

    Subbotin, A.V., E-mail: Alexey.V.Subbotin@gmail.com [Scientific and Production Complex Atomtechnoprom, Moscow 119180 (Russian Federation); Panyukov, S.V., E-mail: panyukov@lpi.ru [PN Lebedev Physics Institute, Russian Academy of Sciences, Moscow 117924 (Russian Federation)

    2016-08-15

    Mechanism of solute-enriched clusters formation in neutron-irradiated pressure vessel steels is proposed and developed in case of Fe-Cu model alloys. The suggested solute-drag mechanism is analogous to the well-known zone-refining process. We show that the obtained results are in good agreement with available experimental data on the parameters of clusters enriched with the alloying elements. Our model explains why the formation of solute-enriched clusters does not happen in austenitic stainless steels with fcc lattice structure. It also allows to quantify the method of evaluation of neutron irradiation dose for the process of RPV steels hardening.

  7. Study on detection method of irradiated frozen foods and others

    International Nuclear Information System (INIS)

    Miyahara, Makoto; Toyoda, Masatake; Saito, Yukio

    1997-01-01

    As detection method of the irradiated foods has history of 20 years, it is said that it has no finished chemical method, which is longed to construct as soon as possible. Up-to-date, many kinds of chemical detection methods have been proposed, the o-tyrosine method thought to be hopeful for the irradiated frozen foods among them was selected to investigate. In this method, phenyl alanine is oxidized with a radical formed on irradiation to tyrosine. The o-tyrosine out of the formed isomers is analyzed quantitatively. When irradiation γ-ray to foods, it was found that amounts of o-tyrosine increased to reach about 2 or 3 times of original amounts. This result was also found to agree with the result reported at the ADMIT conference. Furthermore, possibility of judgement using this method was also shown because of difference on 2 or 3 times of o-tyrosine amounts between unirradiated and over 5 kGy irradiated foods. (G.K.)

  8. Detection of Irradiated Korean Wheat Flour by Viscosity and Pulsed Photostimulated Luminescence (PPSL) Methods

    International Nuclear Information System (INIS)

    Yi, S.D.; Chang, K.S.; Oh, M.J.

    2005-01-01

    This study was carried out to establish methods for irradiation detection of irradiation in Korean wheat flour by pulsed photostimulated luminescence (PPSL) and viscometric methods. The photon counts of the irradiated Korean wheat flour measured by PPSL immediately after irradiation increased with increasing irradiation dose. The photon counts in the irradiated Korean wheat flour almost disappeared with lapse of time after storage in normal room conditions, but irradiation detection was still possible after 6 months in darkroom conditions

  9. Effects of low dose gamma irradiation on PVC blood bags containing anticoagulant CPDA solution

    International Nuclear Information System (INIS)

    Mitra, D.; Varshney, Lalit; Arjun, Chanda

    2006-01-01

    PVC blood bags were exposed to 20Gy and 60Gy low gamma radiation dose to investigate possibility of change in leaching behavior of the plasticizer into CPDA solution and the blood. Reversed phase HPLC was used for the investigations on anti coagulant solution CPDA(citrate, phosphate, dextrose and adenine) contained in PVC bag before and after gamma irradiation. The studies were repeated using methanol as an extractant instead of CPDA solution, considering higher extractability of plasticizer by blood. Irradiation of PVC bags by gamma radiation for a dose up to 60Gy does not lead to change in leaching behavior of the plasticizer in CPDA solution and methanol indicating similar expected behavior in blood. (author)

  10. Analytical solutions for thermal transient profile in solid target irradiated with low energy and high beam current protons

    International Nuclear Information System (INIS)

    Oliveira, Henrique B. de; Brazao, Nei G.; Sciani, Valdir

    2009-01-01

    There were obtained analytical solutions for thermal transient in solid targets, used in short half-life radioisotopes production, when irradiated with low energy and high beam current protons, in the cyclotron accelerator Cyclone 30 of the Institute for Energy and Nuclear Research (IPEN/CNEN-SP). The beam spatial profile was considered constant and the time depended heat distribution equation was resolved for a continuous particles flow entering the target. The problem was divided into two stages: a general solution was proposed which is the sum of two functions, the first one related to the thermal equilibrium situation and the second one related to a time dependent function that was determinate by the setting of the contour conditions and the initial conditions imposed by the real problem. By that one got an analytic function for a complete description of the heat transport phenomenon inside the targets. There were used both, numerical and symbolic computation methods, to obtain temperature maps and thermal gradients and the results showed an excellent agreement when compared with purely numerical models. The results were compared with obtained data from Gallium-67 and Thallium-201 irradiation routines conducted by the IPEN Cyclotrons accelerators center, showing excellent agreement. The objective of this paper is to develop solid targets irradiation systems (metals and oxides) so that one can operate with high levels of current beam, minimizing the irradiation time and maximizing the final returns. (author)

  11. Valency stabilization of Polyvalent Iron Ions in Solution By some Organic additives during Gamma Irradiation

    International Nuclear Information System (INIS)

    Barakat, M.F.; Abdel Hamid, M.M.

    2012-01-01

    Valency stabilization of polyvalent ions in gamma irradiated aqueous solutions is sometimes necessary for the success of some chemical operations. In some previous publications valency stabilization of some polyvalent ions in solution upon gamma irradiation was achieved by using additives capable of interacting with the oxidizing or reducing species formed by water radiolysis in the medium. The results showed that the duration of valency stabilization depends on the concentration of the additives used.In the present work, a series of some organic additives has been used to investigate their capability in inducing valency stabilization of polyvalent iron ions when subjected to extended gamma irradiation periods. The results showed that the efficiency of valency stabilization depends on the amount and chemical structure of the organic additive used

  12. Detection of hypoxanthine, xanthine and uric acid in γ-irradiated aqueous solution of cytosine

    International Nuclear Information System (INIS)

    Kobayashi, Tsuya; Shirai, Kazuo

    1979-01-01

    The aqueous solution of cytosine of 3.6 x 10 -2 M was irradiated with gamma -ray (60 megarad) in nitrogen-saturated glass ampules, and freeze-dried, then the residue obtained was changed to trimethylsilylacid, and this was analyzed by paper chromatography, UV spectrometry, and/or gas-liquid chromatography. Hypoxanthine, xanthine and uric acid were detected in this solution, in addition to some other compounds already known to be produced by gamma -irradiation, e.g., TMS-uracil, TMS-6-hydroxyuracil and TMS-hypoxanthine. It was presumed that these compounds were formed by the recombination of the primary radiolytic products. Uric acid formation by this mechanism was confirmed by gamma -irradiation of the mixture that contained urea, and 5- and 6-hydroxyuracil. (Kaihara, S.)

  13. Comparison of thermoluminescence detection methods for irradiated spices

    International Nuclear Information System (INIS)

    Kawamura, Y.; Murayama, M.; Uchiyama, S.; Saito, Y.

    1996-01-01

    Thermoluminescence (TL) analysis has been shown to be one of the most applicable methods for the detection of γ-irradiated spices. This analysis was introduced as a detection technique for irradiated spices using the whole sample. It was then found that the origin of the TL response to be mineral dust adhering to the spices. TL measurements on separated minerals and the normalised TL measurement by re-irradiation was then established. This paper details investigations on TL measurements carried out using clean powdered spices stored for one year after being irradiated with doses of 1, 5, 10 and 30 kGy in order to clarify their applicable dose range, the effect of storage and mineral content. The effect of the mineral separation was also studied. (author)

  14. Reduction of potassium permanganate solution by γ-irradiated sodium chloride [Paper No. RD-21

    International Nuclear Information System (INIS)

    Phansalkar, V.K.; Ravishankar, D.

    1982-01-01

    The dissolution of γ-irradiated sodium chloride in potassium permanganate solution results in the reduction of MnO 4 - ions. This has been inferred from spectrophotometric studies. This has been explained on the basis of interaction of colour centres with MnO 4 - ions. The extent to which MnO 4 - ions are reduced are found to vary with

  15. Fine interstitial clusters as recombinators in decomposing solid solutions under irradiation

    International Nuclear Information System (INIS)

    Trushin, Yu.V.

    1991-01-01

    Behaviour of interstitial clusters and their roll in processes of radiation swelling of metals are described. It is shown that occurrence of coherent advanced precipitations during decomposition of solid solutions under irradiation leads to matrix supersaturation over interstitial atoms. This enhances recombination of unlike defects due to vacancy precipitation on fine interstitial clusters. Evaluation of cluster sizes was conducted

  16. Oxidative degradation of alternative gasoline oxygenates in aqueous solution by ultrasonic irradiation: Mechanistic study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Duk Kyung, E-mail: dkim@aum.edu [Department of Physical Science, Auburn University Montgomery, Montgomery, AL 36117 (United States); O' Shea, Kevin E., E-mail: osheak@fiu.edu [Department of Chemistry and Biochemistry, Florida International University, University Park, Miami, FL 33199 (United States); Cooper, William J. [Department of Civil and Environmental Engineering, Urban Water Research Center, University of California Irvine, Irvine, CA 92697-2175 (United States)

    2012-07-15

    Widespread pollution has been associated with gasoline oxygenates of branched ethers methyl tert-butyl ether (MTBE), di-isopropyl ether (DIPE), ethyl tert-butyl ether (ETBE), and tert-amyl ether (TAME) which enter groundwater. The contaminated plume develops rapidly and treatment for the removal/destruction of these ethers is difficult when using conventional methods. Degradation of MTBE, with biological methods and advanced oxidation processes, are rather well known; however, fewer studies have been reported for degradation of alternative oxygenates. Degradation of alternative gasoline oxygenates (DIPE, ETBE, and TAME) by ultrasonic irradiation in aqueous oxygen saturation was investigated to elucidate degradation pathways. Detailed degradation mechanisms are proposed for each gasoline oxygenate. The common major degradation pathways are proposed to involve abstraction of {alpha}-hydrogen atoms by hydroxyl radicals generated during ultrasound cavitation and low temperature pyrolytic degradation of ETBE and TAME. Even some of the products from {beta}-H abstraction overlap with those from high temperature pyrolysis, the effect of {beta}-H abstraction was not shown clearly from product study because of possible 1,5 H-transfer inside cavitating bubbles. Formation of hydrogen peroxide and organic peroxides was also determined during sonolysis. These data provide a better understanding of the degradation pathways of gasoline oxygenates by sonolysis in aqueous solutions. The approach may also serve as a model for others interested in the details of sonolysis. - Highlights: Black-Right-Pointing-Pointer Gasoline oxygenates (ETBE, TAME, DIPE) were completely degraded after 6 hours under ultrasonic irradiation in O{sub 2} saturation. Black-Right-Pointing-Pointer The major degradation pathways were proposed to involve abstraction of {alpha}-hydrogen atoms by hydroxyl radicals and low temperature pyrolytic degradation. Black-Right-Pointing-Pointer The effect of {beta

  17. Leaching of irradiated polymers: solution characterization and actinides complexation

    International Nuclear Information System (INIS)

    Fromentin, Elodie

    2017-01-01

    The first aim of this work is to study the degradation of an industrial poly-esterurethane (PURm) by radio-oxidation and then by leaching in an alkaline aqueous solution. The second aim is to measure the complexing power of hydro-soluble degradation products (HDP) with actinides. To reach these goals, PURm was first characterized and then radio-oxidized at room temperature with γ rays up to 10 MGy. Second, it was leached at pH 13.3 at different temperature values. Numerous analytical techniques were employed in order to characterize the HDP which were obtained. Europium(III) was used as an analogue of actinides(III) and the behavior of HDP with europium(III) was analyzed by time-resolved luminescence spectroscopy (TRLS). Whatever the dose received by PURm, adipic acid and butane-1,4-diol are the two main HDP in leachates. The leaching data acquired at 40 and 60 C, on the 1 MGy radio-oxidized PURm, correlate with the model given by Yoon et al. (1997). However, the data at room temperature (22 C in average) are not in agreement with the model. Nevertheless, it seems that the plateau which was reached at long-term leaching is the same whatever the temperature used in this study. The results allow to conclude that the predominant mechanism occurring during the leaching of unirradiated and radio-oxidized PURm in an alkaline medium is the hydrolysis of the soft segments ester groups. The complexation of europium(III) by HDP in alkaline medium was demonstrated. The measurement of the complexing power and the identification of ligands was achieved under certain conditions. (author) [fr

  18. Exact solutions to some nonlinear PDEs, travelling profiles method

    Directory of Open Access Journals (Sweden)

    Noureddine Benhamidouche

    2008-04-01

    \\end{equation*} by a new method that we call the travelling profiles method. This method allows us to find several forms of exact solutions including the classical forms such as travelling-wave and self-similar solutions.

  19. Study on optimizing ultrasonic irradiation period for thick polycrystalline PZT film by hydrothermal method.

    Science.gov (United States)

    Ohta, Kanako; Isobe, Gaku; Bornmann, Peter; Hemsel, Tobias; Morita, Takeshi

    2013-04-01

    The hydrothermal method utilizes a solution-based chemical reaction to synthesize piezoelectric thin films and powders. This method has a number of advantages, such as low-temperature synthesis, and high purity and high quality of the product. In order to promote hydrothermal reactions, we developed an ultrasonic assisted hydrothermal method and confirmed that it produces dense and thick lead-zirconate-titanate (PZT) films. In the hydrothermal method, a crystal growth process follows the nucleation process. In this study, we verified that ultrasonic irradiation is effective for the nucleation process, and there is an optimum irradiation period to obtain thicker PZT films. With this optimization, a 9.2-μm-thick PZT polycrystalline film was obtained in a single deposition process. For this film, ultrasonic irradiation was carried out from the beginning of the reaction for 18 h, followed by a 6 h deposition without ultrasonic irradiation. These results indicate that the ultrasonic irradiation mainly promotes the nucleation process. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Import control of irradiated foods by the thermoluminescence method

    International Nuclear Information System (INIS)

    Pinnioja, S.; Autio, T.; Niemi, E.; Pensala, O.

    1993-01-01

    A thermoluminescence (TL) method was applied for the import control of irradiated foods. The method is based on the determination of the TL of mineral contaminants in foods. Detection of irradiation was incorporated in official Finnish control procedures in spring 1990. For foodstuffs with a reduced microbe content and in which no fumigant residues are found, possible irradiation is investigated by the TL method. The minerals are separated from the foods in different ways: picking is used for spices; water rinsing for herbs, spices, berries and mushrooms; high-density liquid to separate the organic material from the mineral fraction in seafood; and carbon tetrachloride for foods forming gels with water. To date about 140 food samples have been analysed for control purposes: 50 samples of herbs and spices, 25 samples of berries and mushrooms and 65 samples of seafood. Of these, 14 samples of herbs and spices and 5 samples of seafood were shown to have been irradiated. Differences in TL intensity between irradiated and unirradiated samples were at least 1 and usually 3-4 orders of magnitude. (orig.)

  1. Method of determining the position of an irradiated electron beam

    International Nuclear Information System (INIS)

    Fukuda, Wataru.

    1967-01-01

    The present invention relates to the method of determining the position of a radiated electron beam, in particular, the method of detecting the position of a p-n junction by a novel method when irradiating the electron beam on to the semi-conductor wafer, controlling the position of the electron beam from said junction. When the electron beam is irradiated on to the semi-conductor wafer which possesses the p-n junction, the position of the p-n junction may be ascertained to determine the position of the irradiated electron beam by detecting the electromotive force resulting from said p-n junction with a metal disposed in the proximity of but without mechanical contact with said semi-conductor wafer. Furthermore, as far as a semi-conductor wafer having at least one p-n junction is concerned, the present invention allows said p-n junction to be used to determine the position of an irradiated electron beam. Thus, according to the present invention, the electromotive force of the electron beam resulting from the p-n junction may easily be detected by electrostatic coupling, enabling the position of the irradiated electron beam to be accurately determined. (Masui, R.)

  2. Effect of solute elements in Ni alloys on blistering under He + and D + ion irradiation

    Science.gov (United States)

    Wakai, E.; Ezawa, T.; Takenaka, T.; Imamura, J.; Tanabe, T.; Oshima, R.

    2007-08-01

    Effects of solute atoms on microstructural evolution and blister formation have been investigated using Ni alloys under 25 keV He + and 20 keV D + irradiation at 500 °C to a dose of about 4 × 10 21 ions/m 2. The specimens used were pure Ni, Ni-Si, Ni-Co, Ni-Cu, Ni-Mn and Ni-Pd alloys. The volume size factors of solute elements for the Ni alloys range from -5.8% to +63.6%. The formations of blisters were observed in the helium-irradiated specimens, but not in the deuteron-irradiated specimens. The areal number densities of blisters increased with volume size difference of solute atoms. The dependence of volume size on the areal number densities of blisters was very similar to that of the number densities of bubbles on solute atoms. The size of the blisters inversely decreased with increasing size of solute atoms. The formation of blisters was intimately related to the bubble growth, and the gas pressure model for the formation of blisters was supported by this study.

  3. Experimental method for investigating helium effects in irradiated vanadium

    International Nuclear Information System (INIS)

    Smith, D.L.; Matsui, H.; Greenwood, L.; Loomis, B.

    1987-10-01

    Analyses have been performed which indicate that an effective method for experimentally investigating helium effects in neutron irradiated vanadium base alloys can be developed. The experimental procedure involves only modest modifications to existing procedures currently used for irradiation testing of vanadium-base alloys in the FFTF reactor. Helium is generated in the vanadium alloy by decay of tritium which is either preinjected or generated within the test capsule. Calculations indicate that nearly constant He/dpa ratios of desired magnitude can be attained by proper selection of experimental parameters. The proposed method could have a major impact on the development of vanadium base alloys for fusion reactor applications. 8 refs., 4 figs

  4. General survey of detection methods for irradiation foods

    International Nuclear Information System (INIS)

    Yang, J. S.

    1997-01-01

    The development of detection techniques is needed, in order for regulating authorities to determine whether or not a particular food sample has been irradiated, and label it accordingly so that a consumer's free choice can be exercised. The chemical and physical changes brought about in foods by practical doses of irradiation are very small, and therefore very sensitive methods are required. A number of promising approaches have been developed and evaluated. These include chemical, physical and biological methods ranging from the very simple to highly sophisticated techniques. (author)

  5. A spectrophotometric readout for γ irradiated alanine solution - a dosimetric application

    International Nuclear Information System (INIS)

    Marzouk, Asma

    2007-01-01

    Alanine is a stable dosimeter of reference in its solid state. Its installation in solution as being a dosimetric system of routine remains very useful. A follow-up of the behaviour of the irradiated alanine solution with 15 kGy according to the concentration is carried out by UV-Visible spectrophotometry. The results obtained prove the difficulty in analytical studies of the radiolysis of aqueous solutions by optical absorption due to the ambiguous broad spectra of the species and the reaction products. (Author). 47 refs

  6. Alternative method of portable irradiation of manganese sulphate solution by an plutonium-beryllium source for manganese sulphate bath efficiency measurements; Metodo alternativo de irradiacao portatil da solucao de sulfato de manganes por uma fonte de plutonio-berilio para medicoes de eficiencia do banho de sulfato de manganes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Fellipe Souza da; Martins, Marcelo Marques; Pereira, Walsan Wagner, E-mail: fellipess@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2016-07-01

    This study intends to create an alternative irradiation system from a Plutonium-Beryllium source for manganese sulphate solution using the Monte Carlo code. Thus seeking to eliminate the issue of institutes that do not have reactors or particle accelerators in its infrastructure, in order to optimize and provide independence for them to carry out efficiency measurements of MnSO{sub 4} solution in their own locality. The Monte Carlo simulations defined the technical features of this new system so that the solution reaches the maximum neutron capture by manganese in solution. (author)

  7. Effect of solute atom concentration on vacancy cluster formation in neutron-irradiated Ni alloys

    Science.gov (United States)

    Sato, Koichi; Itoh, Daiki; Yoshiie, Toshimasa; Xu, Qiu; Taniguchi, Akihiro; Toyama, Takeshi

    2011-10-01

    The dependence of microstructural evolution on solute atom concentration in Ni alloys was investigated by positron annihilation lifetime measurements. The positron annihilation lifetimes in pure Ni, Ni-0.05 at.%Si, Ni-0.05 at.%Sn, Ni-Cu, and Ni-Ge alloys were about 400 ps even at a low irradiation dose of 3 × 10 -4 dpa, indicating the presence of microvoids in these alloys. The size of vacancy clusters in Ni-Si and Ni-Sn alloys decreased with an increase in the solute atom concentration at irradiation doses less than 0.1 dpa; vacancy clusters started to grow at an irradiation dose of about 0.1 dpa. In Ni-2 at.%Si, irradiation-induced segregation was detected by positron annihilation coincidence Doppler broadening measurements. This segregation suppressed one-dimensional (1-D) motion of the interstitial clusters and promoted mutual annihilation of point defects. The frequency and mean free path of the 1-D motion depended on the solute atom concentration and the amount of segregation.

  8. An improved synthesis of 1,3,5-triaryl-2-pyrazolines in acetic acid aqueous solution under ultrasound irradiation

    Directory of Open Access Journals (Sweden)

    Lin Zhi-Ping

    2007-03-01

    Full Text Available Abstract Background Pyrazoline derivatives have been found to possess a broad spectrum of biological activities. Among various pyrazoline derivatives, 2-pyrazolines seem to be the most frequently studied. A variety of methods have been reported for the preparation of this class of compound. However, in spite of their potential utility, some of the reported methods suffer from drawbacks such as long reaction times, cumbersome product isolation procedures and environmental concerns. Organic reactions in aqueous media have attracted increasing interest recently because of environmental issues and the understanding of biochemical processes. Ultrasound has increasingly been used in organic synthesis in the last three decades. A large number of organic reactions can be carried out in higher yields, shorter reaction time or milder conditions under ultrasound irradiation. Results Preparation of a series of 1,3,5-triaryl-2-pyrazolines through the reaction of chalcones and phenylhydrazine hydrochloride was carried out in 83–96% yield within 1.5–2 h in sodium acetate-acetic acid aqueous solution under ultrasound irradiation. Conclusion We have described a practical and convenient procedure for the synthesis of 1,3,5-triaryl-2-pyrazolines in sodium acetate-acetic acid aqueous solution at room temperature under ultrasound irradiation.

  9. Degradation of ampicillin in pig manure slurry and an aqueous ampicillin solution using electron beam irradiation

    Science.gov (United States)

    Chung, Byung Yeoup; Kim, Jae-Sung; Lee, Min Hee; Lee, Kang Soo; Hwang, Seon Ah; Cho, Jae Young

    2009-07-01

    This study was carried out to evaluate the efficiency of degradation of antibiotic ampicillin in pig manure slurry and an aqueous ampicillin solution with the use of electron beam irradiation as a function of the absorbed dose. The degradation efficiency of ampicillin was close to 95% at an absorbed dose of 10 kGy. The degradation of ampicillin followed a "first-order" reaction rate with respect to absorbed dose. The results demonstrate that the electron beam irradiation technology is an effective means to remove antibiotics in manure and bodies of water.

  10. Degradation of ampicillin in pig manure slurry and an aqueous ampicillin solution using electron beam irradiation

    International Nuclear Information System (INIS)

    Chung, Byung Yeoup; Kim, Jae-Sung; Lee, Min Hee; Lee, Kang Soo; Hwang, Seon Ah; Cho, Jae Young

    2009-01-01

    This study was carried out to evaluate the efficiency of degradation of antibiotic ampicillin in pig manure slurry and an aqueous ampicillin solution with the use of electron beam irradiation as a function of the absorbed dose. The degradation efficiency of ampicillin was close to 95% at an absorbed dose of 10 kGy. The degradation of ampicillin followed a 'first-order' reaction rate with respect to absorbed dose. The results demonstrate that the electron beam irradiation technology is an effective means to remove antibiotics in manure and bodies of water.

  11. Rapid method for Detection of Irradiation Mango Fruits

    International Nuclear Information System (INIS)

    El Salhy, F.T.

    2011-01-01

    To detect mango fruits which have been exposed to low doses of gamma rays (0.5-3.0 kGy), three recommended methods by European Committee for Standardization (EN 1784:1996, EN 1785:1996 and EN 1787:2000) were used to study the possibility for identification of irradiated mango fruits (Ewais variety). Fresh mangoes were irradiated to different doses (0.5, 0.75, 1.0 and 3.0 kGy). The first method for determining the volatile hydrocarbons (VHC) was carried out by using florisil column then identified by gas chromatography and mass spectrometry (GC-MS). The major VHCs were C14:1, C15:0 and C17:1 at different doses which increased linearly with increasing doses either at low or high doses. The second one for determining the 2-alkyl cyclobutanone (2-DCB) was carried out using florisil chromatography method activated with 20% for separation and identified by GC-MS. 2-DCB bio marker specific for irradiated food proved its presence at the applied doses from 0.75-3.0 kGy but not at 0.5 kGy. All the mentioned compounds could not detected in non-irradiated samples, which mean that these radiolytic products (VHC and 2-DCB) can be used as a detection markers for irradiated mangoes even at low doses. The third one (EN 1787:2000) was conducted by electron spin resonance (ESR) on dried petioles of mangoes. The results proved that ESR was more sensitive for all applied doses.It could be concluded that using the three methods can be succeeded for detection of irradiated mangoes but the rapid one even at low doses with high accuracy was ESR.

  12. Potential new methods of detection of irradiated food

    International Nuclear Information System (INIS)

    Raffi, J.J.

    1991-01-01

    The irradiation of food by X- and gamma-rays and by electron beams is a technological process which may be used for food preservation in addition to heat or chemical treatment. The role of the Community Bureau of Reference - the BCR programme - in this area is to support the development and the improvement of analytical methods required for the preparation and implementation of the European legislation. In this context, after consultation of specialists in the Member States and the EFTA countries, it was decided that the BCR should undertake a collaborative project for the identification of irradiated food. The aim of the Cadarache workshop was to examine the development of new methods of detection and to set up a concerted research action covering four areas: DNA based methods; microbiological and biological methods; physical methods; chemical methods

  13. Solution of the porous media equation by Adomian's decomposition method

    International Nuclear Information System (INIS)

    Pamuk, Serdal

    2005-01-01

    The particular exact solutions of the porous media equation that usually occurs in nonlinear problems of heat and mass transfer, and in biological systems are obtained using Adomian's decomposition method. Also, numerical comparison of particular solutions in the decomposition method indicate that there is a very good agreement between the numerical solutions and particular exact solutions in terms of efficiency and accuracy

  14. Effect of gamma-irradiation on basic dye maxilon blue in aqueous solution

    International Nuclear Information System (INIS)

    Andayani, Winarti; Bagyo, Agustin S.M.; Winarno, Ermin K.; Winarno, Hendig

    1998-01-01

    The effects of radiation of basic dye maxilon blue have been studied. Irradiation was done at various pH (3, 5, 7, 9, and 12) with doses of 0 - 4 kGy/h. at pH 5 irradiation of dye solution with variation of concentration i.e. 10; 25; 50.8; 78.2 and 106 ppm were done. Bubbling of air were done during irradiation of dye solution. Parameters examined were the change of the spectrum by spectrophotometer, the decrease of pH by pH meter and degradation products such as organic acids by HPLC. The results showed that the percentage of degradation at acid pH is higher than that basic and neutral pH. G value (degradation) of the dye at pH 5 was 0.876 with a dose rate of 5 kGy/h. Percentage of decoloration of dye solution at initial concentration 10 and 25 ppm were higher than 90% at dose of 0.5 kGy, dye solution at initial concentration between 50 to 106 ppm were higher than 90% at 2 kGy. The equation of degradation rate of the dye was V=-d(dye)/dt = 1.4 x 10 -2 [dye] 1,1107 ppm/min. Degradation of the dye has first order pseudo with the rate constant of 1.4 x 10 -2 min -1 . Degradation products that could be detected was oxalic acid. (authors)

  15. Investigation of a 0.52 eV absorption band of n-type Ge1-xSix solid solutions irradiated with fast electrons at 77 K

    International Nuclear Information System (INIS)

    Abbasov, Sh.M.; Allakhverdiev, K.R.; Agaverdieva, G.T.; Bakhyshov, N.A.; Nagiev, A.I.

    1987-01-01

    Solid solutions belonging to the Ge 1-x Si x system are among the promising semiconductor materials. There is no published information on the absorption band in the region of 0.52 eV in Ge 1-x Si x solid solutions irradiated with fast electrons. The authors determined the infrared absorption spectra, impurity photoconductivity, and Hall effect of n-type Ge 1-x Si x solid solutions doped with antimony. These solid solutions were irradiated at 77 K with 5 MeV electrons in doses up to 2 x 10 17 cm -2 . This irradiation was carried out by a method described in Ref. 3

  16. Studies on γ-irradiation-induced-degradation of chloramphenicol in aqueous solution

    International Nuclear Information System (INIS)

    Xie Fang; Ha Yiming; Wang Feng; Zhou Hongjie

    2008-01-01

    The irradiation-induced degradation of chloramphenicol by γ-rays in aqueous solution was studied and the radiolytical products were determined. The relationship among degradation rate, absorbed dose and initial concentration have been explored by comparing the position of maximum absorption peaks of chloramphenicol be- fore and after irradiation using high performance liquid chromatography. The identification of radiolytical products has been conducted using liquid chromatography tandem mass spectrometry. It has been found that the relationship among C/C 0 , absorbed dose and initial concentration can be fit with index curve. After irradiation, more than 30 radiolytical products with stable absorption below 278nm could be determined. 8 major radiolytical products with [M-H] - 353, 337, 335(A), 335(B), 319, 289, 127, 166, which are detected in several different conditions, have been picked up. Their possible structures are deducted. (authors)

  17. Concentration dependence of solute atoms on vacancy cluster formation in neutron irradiated Ni alloy

    International Nuclear Information System (INIS)

    Sato, K.; Itoh, D.; Yoshiie, T.; Xu, Q.

    2007-01-01

    Full text of publication follows: One dimensional (1-D) motion of interstitial clusters is important for the microstructural evolution in metals. The movement of interstitial clusters was often observed in neutron irradiated metals by transmission electron microscopy (TEM). Alloying elements are expected to affect the motion of interstitial clusters. Yoshiie et al. have studied the effect of alloying elements in Ni. For example, in neutron irradiated pure Ni, well-developed dislocation networks and voids were observed at 573 K at a dose of 0.026 dpa by TEM. After the addition of 2at.%Si (-5.81% volume size factor to Ni) and Sn (74.08% volume size factor), no voids were detected by TEM observation and positron lifetime measurement. Alloying elements of Si and Sn were expected to prevent the 1-D motion of the interstitial clusters. In this study, the concentration dependence of alloying elements on the 1-D motion of the interstitial clusters was investigated by positron annihilation lifetime measurements, and the microstructural evolution was discussed. Specimens irradiated were 99.99 pure Ni (Johnson Matthey) and Ni based binary alloys, which contain Si, Cu, Ge and Sn as solute atoms. The concentration of solute atoms was 0.05at.%o, 0.3at.% and 2at.%. Neutron irradiation was performed with the Kyoto University Reactor (KUR) and Japan materials testing reactor (JMTR) at Japan Atomic Energy Agency. Neutron dose was 6x10 -5 -1x10 -2 dpa at KUR, and 8x10 -3 -0.3 dpa at JMTR. Irradiation temperature was 573 K at KUR and 563 K at JMTR. After the neutron irradiation, positron annihilation lifetime measurements were performed at room temperature. Microvoids were detected in pure Ni, Ni-0.05%Si, Ni-0.05%Sn, Ni-Cu and Ni-Ge alloys. In Ni-Si and Ni-Sn alloys, the size of microvoids decreased as the concentration of solute atoms increased. This is because the frequency of 1-D motion of the interstitial clusters depends on the alloy concentration. High concentration of alloying

  18. Concentration dependence of solute atoms on vacancy cluster formation in neutron irradiated Ni alloy

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Itoh, D.; Yoshiie, T.; Xu, Q. [Kyoto Univ., Research Reactor Institute, Osaka (Japan)

    2007-07-01

    Full text of publication follows: One dimensional (1-D) motion of interstitial clusters is important for the microstructural evolution in metals. The movement of interstitial clusters was often observed in neutron irradiated metals by transmission electron microscopy (TEM). Alloying elements are expected to affect the motion of interstitial clusters. Yoshiie et al. have studied the effect of alloying elements in Ni. For example, in neutron irradiated pure Ni, well-developed dislocation networks and voids were observed at 573 K at a dose of 0.026 dpa by TEM. After the addition of 2at.%Si (-5.81% volume size factor to Ni) and Sn (74.08% volume size factor), no voids were detected by TEM observation and positron lifetime measurement. Alloying elements of Si and Sn were expected to prevent the 1-D motion of the interstitial clusters. In this study, the concentration dependence of alloying elements on the 1-D motion of the interstitial clusters was investigated by positron annihilation lifetime measurements, and the microstructural evolution was discussed. Specimens irradiated were 99.99 pure Ni (Johnson Matthey) and Ni based binary alloys, which contain Si, Cu, Ge and Sn as solute atoms. The concentration of solute atoms was 0.05at.%o, 0.3at.% and 2at.%. Neutron irradiation was performed with the Kyoto University Reactor (KUR) and Japan materials testing reactor (JMTR) at Japan Atomic Energy Agency. Neutron dose was 6x10{sup -5}-1x10{sup -2} dpa at KUR, and 8x10{sup -3} -0.3 dpa at JMTR. Irradiation temperature was 573 K at KUR and 563 K at JMTR. After the neutron irradiation, positron annihilation lifetime measurements were performed at room temperature. Microvoids were detected in pure Ni, Ni-0.05%Si, Ni-0.05%Sn, Ni-Cu and Ni-Ge alloys. In Ni-Si and Ni-Sn alloys, the size of microvoids decreased as the concentration of solute atoms increased. This is because the frequency of 1-D motion of the interstitial clusters depends on the alloy concentration. High

  19. Dose measurement method suitable for management of food irradiation

    International Nuclear Information System (INIS)

    Tanaka, Ryuichi

    1990-01-01

    The report describes major features of dose measurement performed for the management of food irradiation processes, and dose measuring methods suitable for this purpose, and outlines some activities for establishing international standards for dose measurement. Traceability studies made recently are also reviewed. Compared with the sterilization of medical materials, food irradiation is different in some major points from a viewpoint of dose measurement: foods can undergo significant changes in bulk density, depending on its properties, during irradiation, and the variation in the uniformity of bulk density can be large within an irradiation unit and among different units. An accurate dosimeter and well-established traceability are essential for food irradiation control, and basically a dosimeter should be high in reproducibility and stable in dose response, and should be easy to readjust for eliminating systematic errors. A new type of dosimeter was developed recently, in which ESR is used to measure the free radicals generated by radiations in crystals of alanine, an amino acid. Standardization of large dose measurement procedures has been carried out by committee E10 set up under ASTM. (N.K.)

  20. New LASER fluorometric HPLC detection for ortho-tyrosine in gamma-irradiated phenylalanine solution and pork

    International Nuclear Information System (INIS)

    Miyahara, Makoto; Toyoda, Masatake; Saito, Yukio; Nagasawa, Taeko; Izumi, Keiko; Kitamura, Mayumi

    1999-01-01

    New analytical procedure for o-tyrosine was studied to investigate effects of gamma irradiation on aqueous phenylalanine solution and pork. The process includes extraction and hydrolysis of protein, derivatization of the free amino acid by fluororeagent, and finally separation and detection by LASER fluorometric HPLC. The detection limit was 25ng. To study how the procedure works, irradiated phenylalanine solution and pork were analyzed. The samples were irradiated at doses up to 10 kGy at room temperature. Three tyrosine isomers were detected in phenylalanine solution, and 2 isomers (o-and p-tyrosine) were found in pork. Dose response was found in the formation of the isomers both in phenylalanine solution and in pork. O-tyrosine peak obtained from irradiated pork was separated from interference successfully. Those findings illustrate the procedure may be applicable to detection of irradiated food. (author)

  1. Introduction to DNA methods for identification of irradiated foods

    International Nuclear Information System (INIS)

    Delincee, H.

    1996-01-01

    This brief introduction sets the scene with respect to the presentations in this ADMIT meeting dealing with DNA changes as a tool to detect the radiation processing of food. The choice to examine DNA seems obvious, since DNA is a sensitive cellular target to irradiation and the changes in DNA are responsible for many effects observed in irradiated foods, such as the inactivation of microorganisms, elimination of insects, inhibition of sprouting in bulbs and tubers and delay of ripening in several fruits. Therefore, these changes in DNA should be discernible in microbial or insect DNA or in the nucleic acids in the food itself. If DNA changes were specific to irradiation, a detection method could be designed which would have wide applicability, since most foods are derived from living organisms which all contain DNA. Such a method could almost be the universal method for detecting the radiation treatment of foods. Radiation-induced changes in DNA can be analysed by a variety of analytical techniques, which have mostly been employed on pure DNA or on DNA in living cells in radiation biology research. Whether or not some of these techniques can be utilised to detect irradiated food has recently been very briefly discussed. (author)

  2. A channeling investigation of the interaction between solute atoms and irradiation-produced defects in magnesium

    International Nuclear Information System (INIS)

    Howe, L.M.; Swanson, M.L.; Quenneville, A.F.

    1978-01-01

    The trapping of irradiation-produced defects by solute atoms in Mg crystals was monitored by measuring the displacement of the solute atoms from lattice sites using the backscattering-channeling technique. In Mg-0.2 at.% Ag crystals, irradiation at 30 K with 1 MeVHe + ions resulted in a very large fraction of Ag atoms being displaced from their lattice sites. The Ag atom displacement appeared to be along directions and is attributed to the trapping of migrating Mg interstitial atoms by Ag atoms to form Mg-Ag mixed dumbbells. Recovery of the Ag atom displacements and the irradiation-induced dechanneling increment occurred principally in two stages, 80-160 K (stage III) and 200-280 K (stage IV). Stage III is attributed mainly to some type of interstitial migration and stage IV is attributed to the migration of single vacancies. In contrast to the Mg-Ag results, a very small displaced fraction of Bi atoms occurred in an irradiated Mg-0.08 at.% Bi crystal; hence Mg-Bi mixed dumbbells do not appear to be formed. (author)

  3. Irradiation-Induced Solute Clustering in a Low Nickel FeMnNi Ferritic Alloy

    International Nuclear Information System (INIS)

    Meslin, E.; Barbu, A.; Radiguet, B.; Pareige, P.; Toffolon, C.

    2011-01-01

    Understanding the radiation embrittlement of reactor pressure vessel (RPV) steels is required to be able to operate safely a nuclear power plant or to extend its lifetime. The mechanical properties degradation is partly due to the clustering of solute under irradiation. To gain knowledge about the clustering process, a Fe-1.1 Mn-0.7 Ni (at.%) alloy was irradiated in a test reactor at two fluxes of 0.15 and 9 *10 17 n E≥1MeV . m -2 .s -1 and at increasing doses from 0.18 to 1.3 *10 24 n E≥1MeV ) . m -2 at 300 degrees C. Atom probe tomography (APT) experiments revealed that the irradiation promotes the formation in the α iron matrix of Mn/Mn and/or Ni/Ni pair correlations at low dose and Mn-Ni enriched clusters at high dose. These clusters dissolve partially after a thermal treatment at 400 degrees C. Based on a comparison with thermodynamic calculations, we show that the solute clustering under irradiation can just result from an induced mechanism. (authors)

  4. Detection methods for irradiated foods: current status. Proceedings

    International Nuclear Information System (INIS)

    McMurray, C.H.; Gray, R.; Stewart, E.M.; Pearce, J.; Queen's Univ., Belfast, Northern Ireland

    1996-01-01

    This book contains a scientific record of an international meeting on analytical detection methods for irradiation treatment of food. Apart from encouraging the basic development of detection tests, the meeting also aimed to assess the various test methods critically to determine their suitability for general use by public health laboratories and others concerned with trade in irradiated food. Two sets of criteria have been developed to assess test methods, technical criteria for a qualitative or quantitative test and practical criteria if a method is to be widely applied by food labelling authorities. Agreement has already been achieved for the use of electron spin resonance, thermoluminescence, hydrocarbons, 2-Alkylcyclobutanones, microbiological, viscometry and impedance tests. (UK)

  5. Degradation of Some Pesticides in Aqueous Solutions by Electro Beam and Gamma Irradiation

    International Nuclear Information System (INIS)

    Dessouki, A.M.; Abdel Aal, S.E.; Sokker, H.H.

    2000-01-01

    Decomposition of two pesticides as active ingredient (Lannate and Fenvalarate) present in aqueous solution by ionizing radiations has been studied on laboratory-scale experiments. The effect of ph of the solution, the concentration of the pesticide and the irradiation dose on the degradation process was investigated carried out alone and in combination with other additives such as nitrogen, oxygen and ozone. A synergistic effect was detected which enhanced the degradation process remarkably. Lannate showed more degradation than Fenvalarte under conditions investigated. Radiation alone was not enough to achieve the complete decomposition of the pesticides. Adsorption of the un degraded pollutants was achieved using Granular Activated Carbon (GAC) and two anion exchangers (Dowex 1-X 8 and Lewatit AP 246) It may be concluded that irradiation followed by adsorption resulted in the removal of these organic pollutants from wastewater

  6. Degradation characteristics of irradiated poly-(caprolactonechitosan-hydroxyapatite) biomaterial in simulated body fluid solution

    International Nuclear Information System (INIS)

    Warastuti, Y.; Suryani, N.

    2013-01-01

    This investigation purpose was to study degradation characteristics of poly-(caprolactone -chitosan-hydroxyapatite) biomaterial in simulated body fluid (SBF) solution. A composite membrane has been synthesized using blending and stirring method with acetic acid solvent and then molded into thin film. Electron beam radiation dose 0 - 30 kGy were done in order to evaluate radiation effects. SBF absorption with various immersing times and degradation for 0 -12 weeks were conducted. Fourier Transform Infra Red Spectroscopy (FTIR) was used to identification functional groups of composite and Scanning Electron Microscopy (SEM) was applied to analyse micro structural surface of membrane before and after immersion. The irradiation process indicate that SBF absorption decrease because NH 2 groups in chitosan which contributes to the hydrophilicity was broken. The composite III indicate maximum absorption (58,2% ± 2,22) due to its smallest concentration of polycaprolactone and highest concentration of chitosan that caused decrease of hydrophobicity. Optimum degradation of composite III (1,3% ± 0,98) was reached after 8 weeks of immersion time. FTIR spectrum indicate the unity of typical peaks of the constituent materials and specific spectrum of CO 3 2- of carbonated apatite which was formed because immersion of SBF. Microstructural analysis using SEM indicate the formation of needle like apatite layer or calcium phosphate precipitate over all surface membrane. All the results indicate that these composite meet the requirements to biomaterial. (author)

  7. Preparation of gold nanoparticles by γ-ray irradiation method using polyvinyl pyrrolidone (PVP) as stabilizer

    International Nuclear Information System (INIS)

    Nguyen Tan Man; Le Hai; Le Huu Tu; Tran Thu Hong; Tran Thi Tam; Pham Thi Le Ha; Pham Thi Sam

    2011-01-01

    Gold nanoparticles were prepared from (Au 3+ ) aqueous solution by the method of γ-ray irradiation using polyvinylpyrrolidone (PVP) as stabilizer. The saturated conversion dose (Au 3+ --> Au o ) determined by UV-Vis spectroscopy was found to be about 5 kGy. The UV-Vis spectrum showed that an absorption peak at λ max =524 nm due to surface plasmon resonance. The image of transmission electron microscopy (TEM) showed that the gold nanoparticles are mostly spherical in shape and have an average diameter of ≅20 nm. The prepared colloidal gold nanoparticles solution is good stability for 6 months of storage. (author)

  8. Photostimulated luminescence, fast method of detection of irradiated foodstuffs

    International Nuclear Information System (INIS)

    Guzik, G.P.; Stachowicz, W.

    2005-01-01

    The principle of pulsed photostimulated luminescence (PPSL) method, description of instrumentation and methodology of measurements are presented. The pathway of operational procedure and testing of the PPSL instrument in the Laboratory for Detection of Irradiated Food of the Institute of Nuclear Chemistry and Technology are described. Attention has been paid to the positives of the new method while some limitation of its application have been also discussed. (author)

  9. Irradiation creep of solution annealed and cold worked 316 stainless steel

    International Nuclear Information System (INIS)

    Boutard, J.L.; Carteret, Y.; Cauvin, R.; Maillard, A.; Guerin, Y.

    1983-01-01

    Irradiation creep strains obtained in-pile on S.A. and C.W. 316 show a linear creep-swelling correlation, the slope of which is rather insensitive to chemical composition and elements in solid solution. The variation of SIPA component resulting only from the evolution of dislocation density and void growth cannot explain such an empirical correlation. The I-creep term has, on the other hand, the right temperature dependence and order of magnitude. (author)

  10. Small interstitial clusters as opposite defect recombinators in decomposing solid solutions under irradiation

    International Nuclear Information System (INIS)

    Orlov, A.N.; Trushin, Yu.V.

    1988-01-01

    An attempt was made to make allowance for the role of binary and ternary interstitials in the kinetics of radiation point defects both in the presence and in the absence of coherent preseparation. It is shown that in solid solutions, decomposing under irradiation, recombination with binary and ternary interstitials proceeds more quickly than directly, and this difference is more pronounced (from 2 up to 20 time growth) due to defect flow for preseparation at the stage of coherent preseparation formation

  11. Effect of gamma irradiation in the viscosity of gelatin and pectin solutions used in food industry

    International Nuclear Information System (INIS)

    Inamura, Patricia Yoko

    2008-01-01

    Pectin is a polysaccharide substance of plant origin that may be used as gelling agent, stabilizer in jams, in yogurt drinks and lactic acid beverages. Gelatin, a protein from bovine origin, in this case, is mainly used as gelling agent due to hydrogel formation during cooling. The 60 Co-irradiation process may cause various modifications in macromolecules, some with industrial application, as reticulation. The dynamic response of viscoelastic materials can be used in order to give information about the structural aspect of a system at molecular level. In the present work samples of pectin with different degree of methoxylation, gelatin and the mixture of both were employed to study the radiation sensitivity by means of viscosity measurements. Solutions prepared with citric pectin with high methoxylation content (ATM) 1 por cent, pectin with low content (BTM) 1 por cent, gelatin 0.5 por cent, 1 por cent and 2 por cent, and the mixture 1 por cent and 2 por cent were irradiated with gamma rays at different doses, up to 15 kGy with dose rate about 2 kGy/h. After irradiation the viscosity was measured within a period of 48 h. The viscosity of ATM and BTM pectin solutions decreased sharply with the radiation dose. However, the gelatin sample presented a great radiation resistance. When pectin and gelatin solutions were mixed a predominance of pectin behavior was found. (author)

  12. An intercomparison experiment on isotope dilution thermal ionisation mass spectrometry using plutonium-239 spike for the determination of plutonium concentration in dissolver solution of irradiated fuel

    International Nuclear Information System (INIS)

    Aggarwal, S.K.; Shah, P.M.; Saxena, M.K.; Jain, H.C.; Gurba, P.B.; Babbar, R.K.; Udagatti, S.V.; Moorthy, A.D.; Singh, R.K.; Bajpai, D.D.

    1996-01-01

    Determination of plutonium concentration in the dissolver solution of irradiated fuel is one of the key measurements in the nuclear fuel cycle. This report presents the results of an intercomparison experiment performed between Fuel Chemistry Division (FCD) at BARC and PREFRE, Tarapur for determining plutonium concentration in dissolver solution of irradiated fuel using 239 Pu spike in isotope dilution thermal ionisation mass spectrometry (ID-TIMS). The 239 Pu spike method was previously established at FCD as viable alternative to the imported enriched 242 Pu or 244 Pu; the spike used internationally for plutonium concentration determination by IDMS in dissolver solution of irradiated fuel. Precision and accuracy achievable for determining plutonium concentration are compared under the laboratory and the plant conditions using 239 Pu spike in IDMS. For this purpose, two different dissolver solutions with 240 Pu/ 239 Pu atom ratios of about 0.3 and 0.07 corresponding, respectively, to high and low burn-up fuels, were used. The results of the intercomparison experiment demonstrate that there is no difference in the precision values obtained under the laboratory and the plant conditions; with mean precision values of better than 0.2%. Further, the plutonium concentration values determined by the two laboratories agreed within 0.3%. This exercise, therefore, demonstrates that ID-TIMS method using 239 Pu spike can be used for determining plutonium concentration in dissolver solution of irradiated fuel, under the plant conditions. 7 refs., 8 tabs

  13. Anionic triphenylmethane dye solutions for low-dose food irradiation dosimetry

    International Nuclear Information System (INIS)

    El-Assy, N.B.; Chen Yundong; Walker, M.L.; Al-Sheikly, M.; McLaughlin, W.L.

    1995-01-01

    The radiolytic bleaching of aryl sulfonic-substituted para-dimethyl-amino triphenylmethane dye solutions can be used for dosimetry in the absorbed dose range 10 to 400 Gy. The sulfonic anions provide solubility of these acid dyes in water. Two of these dyes are supplied as stable greenish-blue biological stains when dissolved in weakly-acidic aqueous solution. Light Green SF Yellowish and Fast Green FCF. They have, respectively, linear molar absorption coefficients of 7.14 x 10 3 (at pH 5.4) and 10.0 x 10 3 (at pH 4.2) m 2 mol -1 , when measured at the peaks of the primary absorption bands, 630 nm and 622 nm, respectively. The bleaching due to irradiation with gamma rays shows a linear function with a positive slope between the negative logarithm of the absorbance and the absorbed dose. The effect of pH on the response is studied, as well as the effects of light and temperature on pre- and post-irradiation stability. A mechanism, based mainly on radiolytic oxidation of the protonated phenolic or sulfonated phenyl group by . OH, with the abstraction of H-atom to water, is postulated for neutral to slightly acidic aerated aqueous solutions. The influence of alcohol on diminishing the negative yield is demonstrated. Alkaline aqueous solutions of these dyes (pH 10.2) have a shorter-wavelength absorption maximum than acidic aqueous solutions. The effect of irradiation is to cause acidification (to pH 7) due to displacement of OH groups and degradation of the dye molecule to lower molecular weight organic acids. (author)

  14. Anionic triphenylmethane dye solutions for low-dose food irradiation dosimetry

    International Nuclear Information System (INIS)

    El-Assy, N.B.; Chen Yungdong; Walker, M.L.; Al-Sheikhly, M.; McLaughlin, W.L.

    1995-01-01

    The radiolytic bleaching of aryl sulfonic-substituted para-diethyl-amino triphenylmethane dye solutions can be used for dosimetry in the absorbed dose range 10 to 400 Gy. The sulfonic anions provide solubility of these acid dyes in water. Two of these dyes are supplied as stable greenish-blue biological stains when dissolved in weakly-acidic aqueous solution, Light Green SF Yellowish and Fast Green FCF. They have, respectively, linear molar absorption coefficients of 7.14 x 10 3 (at pH 5.4) and 10.0 x 10 3 (at pH 4.2) m 2 mol -1 , when measured at the peaks of the primary absorption bands, 630 nm and 622 nm, respectively. The bleaching due to irradiation with gamma rays shows a linear function with a positive slope between the negative logarithm of the absorbance and the absorbed dose. The effect of pH on the response is studied, as well as the effects of light and temperature on pre- and post-irradiation stability. A mechanism, based mainly on radiolytic oxidation of the protonated phenolic or sulfonated phenyl group by radicalOH, with the abstraction of H-atom to water, is postulated for neutral to slightly acidic aerated aqueous solutions. The influence of alcohol on diminishing the negative yield is demonstrated. Alkaline aqueous solutions of these dyes (pH 10.2) have a shorter-wavelength absorption maximum than acidic aqueous solutions. The effect of irradiation is to cause acidification (to pH 7) due to displacement of OH groups and degradation of the dye molecule to lower molecular weight organic acids. (author)

  15. Using activation method to measure neutron spectrum in an irradiation chamber of a research reactor

    International Nuclear Information System (INIS)

    Zhou Xuemei; Liu Guimin; Wang Xiaohe; Li Da; Meng Lingjie

    2014-01-01

    Neutron spectrum should be measured before test samples are irradiated. Neutron spectrum in an irradiation chamber of a research reactor was measured by using activation method when the reactor is in normal operation under 2 MW. Sixteen kinds of non-fission foils (19 reaction channels) were selected, of which 10 were sensitive to thermal and intermediate energy regions, while the others were of different threshold energy and sensitive to fast energy regions. By measuring the foil radioactivity, the neutron spectrum was unfolded with the iterative methods SAND-II and MSIT. Finally, shielding corrections of group cross-section and main factors affecting the calculation accuracy were studied and the uncertainty of solution was analyzed using the Monte Carlo method in the process of SAND-II. (authors)

  16. Isotope dilution alpha spectrometry for the determination of plutonium concentration in irradiated fuel dissolver solution : IDAS and R-IDAS

    International Nuclear Information System (INIS)

    Ramaniah, M.V.; Jain, H.C.; Aggarwal, S.K.; Chitambar, S.A.; Kavimandan, V.D.; Almaula, A.I.; Shah, P.M.; Parab, A.R.; Sant, V.L.

    1980-01-01

    The report presents a new technique, Isotope Dilution Alpha Spectrometry (IDAS) and Reverse Isotope Dilution Alpha Spectrometry (R-IDAS) for determining the concentration of plutonium in the irradiated fuel dissolver solution. The method exploits sup(238)Pu in IDAS and sup(239)Pu in R-IDAS as a spike and provides an alternative method to Isotope Dilution Mass Spectrometry (IDMS) which requires enriched sup(242)Pu as a spike. Depending upon the burn-up of the fuel, sup(238)Pu or sup(239)Pu is used as a spike to change the sup(238)Pu/(sup(239)Pu+sup(240)Pu)α activity ratio in the sample by a factor of 10. This change is determined by α-spectrometry on electrodeposited sources using a solid state silicon surface barrier detector coupled to a multichannel analyser. The validity of a simple method based on the geometric progression (G.P.) decrease for the far tail of the spectrum to correct for the tail contribution of sup(238)Pu peak (5.50 MeV) to the low energy sup(239)Pu + sup(240)Pu peak (5.17 MeV) is established. Results for the plutonium concentration on different irradiated fuel dissolver solutions with burn-uo ranging from J,000 to 100,000 MWD/TU are presented and compared with those obtained by IDMS. The values obtained by IDAS or R-IDAS and IDMS agree within 0.5%. (auth.)

  17. Preliminary studies on 1-vinyl-2-pyrrolidone grafting onto cellulose by pre-irradiation method

    Energy Technology Data Exchange (ETDEWEB)

    Severich, Patrick; Dutra, Rodrigo da Costa; Kodama, Yasko, E-mail: ykodama@ipen.br, E-mail: patrick.severich@ipen.br, E-mail: rodrigo.dutra@ipen.br [Instituto de Pesquisas Energética s e Nucleares (IPEN-CNEN/SP), São Paulo, SP (Brazil)

    2017-07-01

    Cellulose is considered a renewable biopolymer most abundant in nature. Better functional surfaces can be Obtained by modifying cellulose. On the other hand, poly vinyl pyrrolidone, PVP, is a synthetic nontoxic, water-soluble polymer frequently used in an extensive variety of applications including several pharmaceutical applications. Grafting 1-vinyl-2-pyrrolidone, NVP, onto polymeric cellulose can be obtained by ionizing radiation. Ionizing radiation grafting can be affected by several factors as environment, solvent, monomer concentration, temperature of graft reaction. Grafting by ionizing radiation can be performed by three methods, pre-irradiation, oxidation by peroxide and simultaneous irradiation. In this study, it was used pre-irradiation method of cellulose. Paper filter without ash, NVP without purification was used in this study. Paper samples were exposed to electron beam from Dynamitron Accelerator with radiation absorbed dose of 25 kGy. Influence of NVP concentration, temperature of reaction after irradiation on degree of grafting (DG) was studied. Also, cellulose radicals of grafted paper samples was studied by electron paramagnetic resonance using a Bruker X-band ESR at room temperature just after heating reaction. Small decrease of cellulose radicals was observed with increasing reaction temperature. It was observed DG small increase with increasing concentration of monomer in solution of water ethanol 50-50 v:v and rising temperature of reaction. Further tests using simultaneous method of grafting of NVP in cellulose paper, in water:ethanol 75:25 v:v solution, induced by gamma irradiation were performed. It was observed homopolymerization forming PVP with increasing monomer concentration. (author)

  18. Preliminary studies on 1-vinyl-2-pyrrolidone grafting onto cellulose by pre-irradiation method

    International Nuclear Information System (INIS)

    Severich, Patrick; Dutra, Rodrigo da Costa; Kodama, Yasko

    2017-01-01

    Cellulose is considered a renewable biopolymer most abundant in nature. Better functional surfaces can be Obtained by modifying cellulose. On the other hand, poly vinyl pyrrolidone, PVP, is a synthetic nontoxic, water-soluble polymer frequently used in an extensive variety of applications including several pharmaceutical applications. Grafting 1-vinyl-2-pyrrolidone, NVP, onto polymeric cellulose can be obtained by ionizing radiation. Ionizing radiation grafting can be affected by several factors as environment, solvent, monomer concentration, temperature of graft reaction. Grafting by ionizing radiation can be performed by three methods, pre-irradiation, oxidation by peroxide and simultaneous irradiation. In this study, it was used pre-irradiation method of cellulose. Paper filter without ash, NVP without purification was used in this study. Paper samples were exposed to electron beam from Dynamitron Accelerator with radiation absorbed dose of 25 kGy. Influence of NVP concentration, temperature of reaction after irradiation on degree of grafting (DG) was studied. Also, cellulose radicals of grafted paper samples was studied by electron paramagnetic resonance using a Bruker X-band ESR at room temperature just after heating reaction. Small decrease of cellulose radicals was observed with increasing reaction temperature. It was observed DG small increase with increasing concentration of monomer in solution of water ethanol 50-50 v:v and rising temperature of reaction. Further tests using simultaneous method of grafting of NVP in cellulose paper, in water:ethanol 75:25 v:v solution, induced by gamma irradiation were performed. It was observed homopolymerization forming PVP with increasing monomer concentration. (author)

  19. Method of processing plutonium and uranium solution

    International Nuclear Information System (INIS)

    Otsuka, Katsuyuki; Kondo, Isao; Suzuki, Toru.

    1989-01-01

    Solutions of plutonium nitrate solutions and uranyl nitrate recovered in the solvent extraction step in reprocessing plants and nuclear fuel production plants are applied with low temperature treatment by means of freeze-drying under vacuum into residues containing nitrates, which are denitrated under heating and calcined under reduction into powders. That is, since complicate processes of heating, concentration and dinitration conducted so far for the plutonium solution and uranyl solution are replaced with one step of freeze-drying under vacuum, the process can be simplified significantly. In addition, since the treatment is applied at low temperature, occurrence of corrosion for the material of evaporation, etc. can be prevented. Further, the number of operators can be saved by dividing the operations into recovery of solidification products, supply and sintering of the solutions and vacuum sublimation. Further, since nitrates processed at a low temperature are powderized by heating dinitration, the powderization step can be simplified. The specific surface area and the grain size distribution of the powder is made appropriate and it is possible to obtain oxide powders of physical property easily to be prepared into pellets. (N.H.)

  20. Development of DNA elution method to detect irradiated foodstuff

    International Nuclear Information System (INIS)

    Copin, M.P.; Bourgeois, C.M.

    1991-01-01

    The aim of the work is to develop a reliable method to detect whether a fresh and frozen foodstuff has been irradiated. The molecule of DNA is one of the targets of ionizing radiation. The induction of three major classes of lesion have been shown. Double strand breaks, single strand breaks and base damage. Among the different techniques used to observe and quantify the strand breaks, techniques of elution are very interesting. The method proposed consisted of a filtration of the DNA at the atmospheric pressure and in non denaturing conditions. The amount of DNA retained on the filter is measured after being suitably labelled by microfluorometry. A difference in the amount of DNA retained on a filter of 2 μm from a lysed muscular tissue sample between a frozen Norway lobster which has been irradiated and one which has not, is observed. 7 refs

  1. Thermally stimulated current method applied to highly irradiated silicon diodes

    CERN Document Server

    Pintilie, I; Pintilie, I; Moll, Michael; Fretwurst, E; Lindström, G

    2002-01-01

    We propose an improved method for the analysis of Thermally Stimulated Currents (TSC) measured on highly irradiated silicon diodes. The proposed TSC formula for the evaluation of a set of TSC spectra obtained with different reverse biases leads not only to the concentration of electron and hole traps visible in the spectra but also gives an estimation for the concentration of defects which not give rise to a peak in the 30-220 K TSC temperature range (very shallow or very deep levels). The method is applied to a diode irradiated with a neutron fluence of phi sub n =1.82x10 sup 1 sup 3 n/cm sup 2.

  2. Swelling behavior of γ-ray irradiated elastomers in boiling spray solution

    International Nuclear Information System (INIS)

    Yagi, Toshiaki; Kusama, Yasuo; Ito, Masayuki; Okada, Sohei; Yoshikawa, Masahito; Yoshida, Kenzo

    1983-05-01

    Elastomers swelled significantly by water sorption during a simulated LOCA test, and this phenomenon could cause the deterioration of their mechanical and electrical properties. Many factors like as radiation, heat, the composition of spray solution, types of elastomers and their formulation, related to the phenomenon. A relationship between swelling properties of the formulation-known various elastomers and the pre-aging conditions such as radiation dose and thermal aging period was studied by measuring their swelling behaviors in boiling spray solution (water and chemical solution). All eight elastomers tested showed remarkable swelling with an increase of radiation dose when they irradiated in air. A swelling in boiling water was about twice of in chemical solution. Some types of Neoprene and Hypalons had an optimum swelling dose where they showed the maxima. Over this dose, the swelling ratio decreased with dose. When irradiated under vacuum, its swelling ratio became significantly lower than that of exposed in air. This attributed the swelling phenomena closely related to radiation oxidation degradation. (author)

  3. The effects of H2SO4 and NaOH solutions on irradiated sawdust for ethanol production

    International Nuclear Information System (INIS)

    Lina, M.R.; Susiana; Siagian, E.G.

    1988-01-01

    The research of gamma irradiated sawdust, which were added H2SO4 and NaOH solutions on fermentation process for ethanol production was investigated. Irradiation doses used were : 0 and 200 kGy, while H2SO4 and NaOH solutions had concentrations of 0,1 and 2% (v/v) and (b/v), with a ratio of sawdust weight and solution volume = 1:3. Fine powder of sawdust with a mesh of 60, was hydrolysed by enzyme (cellulase), S.cerevisiae was a yeast used for fermentation process and fermentation time was 4 hours. From the experimental results showed that irradiation doses up to 200 kGy, could increase the ethanol concentration from sawdust fermentation signivicantly (P= . Irradiation treatment, addition of the solutions and its interaction could not influence the total carbohydrate before and after fermentation. (author). 9 refs, 2 figs, 6 tabs

  4. Effect of γ-irradiation on spectral characteristics of oxyhemoglobin solutions of mice in the presence of serotin

    International Nuclear Information System (INIS)

    Artyukhov, V.G.; Sviridova, Eh.V.

    1977-01-01

    Study of spectral characteristics of oxyhemoglobin solutions (0.5 x 10 -5 M) γ-irradiated in the presence of serotonin (5 x 10 -5 M) has demonstrated that serotonin has a protective action on oxyhemoglobin. The protective effect of serotonin was also observed in relation to irradiated oxyhemoglobin solutions incubated for 30 min at 45 deg C. It is suggested that the protective action of serotonin may be due to the formation of H 2 O 2 /serotonin complex

  5. Development of a new method for 111In production through the irradiation of Cd with protons

    International Nuclear Information System (INIS)

    Lion, Luciana Farias de

    2002-01-01

    111 In (t 1/2 = 2,83 d) has favourable characteristics for its use in Nuclear Medicine and it is one of radioisotopes of interest of Brazilian physicians. 111 In decays 100% by electron capture with emission of gamma rays of 171.28 and 245.38 keV that are in the maximum detection range of equipment used for diagnosis. 111 In has been broadly used in molecules labelling such as monoclonal antibodies and peptides for tumour localization. A new method of 111 In production was developed through the irradiation of Cd with protons. The chosen nuclear reaction, 112 Cd(p,2n) 11l n, has suitable yields for a routine production by using an enriched Cd target. This work was done with natural Cd targets that were prepared by electroplating of CdS0 4 solution in a copper/nickel backing. The irradiations were made at CV-28 and Cyclone 30 Cyclotrons at IPEN-CNEN/SP Chemical separation was performed by thermal diffusion technique in which the irradiated targets were heated up to 300 deg C. Then, the irradiated targets were immersed in acetic acid for extraction of 111 In and the collected solution was purified in anionic resin. The final solution of 111 In presented appropriated chemical and radionuclidic purities for its use in Nuclear Medicine, 114m In (t 1/2 = 49.5 d) was the main radionuclide impurity produced by activation of natural Cd, This work presents a new method for production of 111 In, where the chemical separation was done by a non-destructive technique of the target that can be easily automated and finally, it has purities and yields suitable for routine production at IPEN-CNEN/SP. (author)

  6. Gamma-irradiation of malic acid in aqueous solutions. [prebiotic significance

    Science.gov (United States)

    Negron-Mendoza, A.; Graff, R. L.; Ponnamperuma, C.

    1980-01-01

    The gamma-irradiation of malic acid in aqueous solutions was studied under initially oxygenated and oxygen-free conditions in an attempt to determine the possible interconversion of malic acid into other carboxylic acids, specifically those associated with Krebs cycle. The effect of dose on product formation of the system was investigated. Gas-liquid chromatography combined with mass spectrometry was used as the principal means of identification of the nonvolatile products. Thin layer chromatography and direct probe mass spectroscopy were also employed. The findings show that a variety of carboxylic acids are formed, with malonic and succinic acids in greatest abundance. These products have all been identified as being formed in the gamma-irradiation of acetic acid, suggesting a common intermediary. Since these molecules fit into a metabolic cycle, it is strongly suggestive that prebiotic pathways provided the basis for biological systems.

  7. Irradiation with benzene, toluene and phenol electron beams in aqueous solution

    International Nuclear Information System (INIS)

    Santoyo O, E.L.; Lopez V, H.; Vazquez A, O.; Lizama S, B.E.; Garcia F, M.

    1998-01-01

    It is described a methodology for waste water treatment which is simulated doing a benzene-toluene-phenol mixture in aqueous solution. Three different concentrations of them ones were used which were irradiated with electron beams coming from a Pelletron Accelerator carrying out the degradation effect of these compounds in CO 2 and H 2 O. By mean of gas chromatography the analytical determinations were realized finding that in lower concentration of benzene and toluene performances of degradation higher than 95 % were obtained, but higher concentrations (100 ppm) the performance diminishes at 89 %, while for phenol in higher concentrations its degradation is over 60 % and in lower concentrations the degradation is under 80 %. The results are obtained with a constant irradiation time of 12 seconds and neutral pH. (Author

  8. Formation of amino acids by cobalt-60 irradiation of hydrogen cyanide solutions

    Science.gov (United States)

    Sweeney, M. A.; Toste, A. P.; Ponnamperuma, C.

    1976-01-01

    Experiments were conducted to study the pathway for the prebiotic origin of amino acids from hydrogen cyanide (HCN) under the action of ionizing radiation considered as an effective source of energy on the primitive earth. The irradiations were performed in a cobalt-60 source with a dose rate of 200,000 rad/hr. Seven naturally occurring amino acids are identified among the products formed by the hydrolysis of gamma-irradiated solutions of HCN: glycine, alanine, valine, serine, threonine, aspartic acid, and glutamic acid. The identity of these amino acids is established by gas chromatography and mass spectrometry. Control experiments provided evidence that the amino acids are not the result of contamination.

  9. PARALLEL SOLUTION METHODS OF PARTIAL DIFFERENTIAL EQUATIONS

    Directory of Open Access Journals (Sweden)

    Korhan KARABULUT

    1998-03-01

    Full Text Available Partial differential equations arise in almost all fields of science and engineering. Computer time spent in solving partial differential equations is much more than that of in any other problem class. For this reason, partial differential equations are suitable to be solved on parallel computers that offer great computation power. In this study, parallel solution to partial differential equations with Jacobi, Gauss-Siedel, SOR (Succesive OverRelaxation and SSOR (Symmetric SOR algorithms is studied.

  10. Endolymphatic irradiation. A useful method for immunosuppression in renal transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Galvao, M.M.; Ianhez, L.E.; Sabbaga, E. (Sao Paulo Univ. (Brazil). Faculdade de Medicina)

    1982-02-01

    The authors analysed the clinical evolution and the result of renal transplantation some years after irradiation in 24 patients (group I) who received endolymphatic /sup 131/I as a pre-transplantation immunosuppresive measure. The control group (group II) consisted of 24 non-irradiated patients comparable to group I in age, sex, primary disease, type of donor and immunosuppressive therapy. Significant differences were observed between the two groups regarding such factors as incidence and reversibility of rejection crises in the first 60 post-transplantation days, loss of kidney due to rejection, and dosage of azathioprine. The authors conclude that this method, besides being harmless, has prolonged immunosuppressive action, its administration being advised for receptors of cadaver kidneys, mainly those who show positive cross-match against HLA antigens for painel.

  11. Comparison of different skin preservation methods with gamma irradiation.

    Science.gov (United States)

    Guerrero, Linda; Camacho, Bernardo

    2017-06-01

    Allografts are in constant demand, not only for burn victims, but also for all open wounds as "biological dressings". Tissue quality and security are two of the major concerns of Tissue Banks. There are limited studies published. There has been extensive discussion on the subject of preservation methods for cadaver skin. Most literature available comes from clinical reports. In this research, the authors compared 85% glycerolized non irradiated skin allografts with three glycerolized irradiated skin allografts (using different glycerol concentrations 50%, 70% and 85%). The evaluation of allograft quality was done by measuring physical and biological properties of such prepared human tissue grafts. In the histological structure evaluation changes were minimal and did not alter the skin structure. The clinical function of their behavior as temporal dressings was tested. They proved to have similar capabilities for improving granulating tissue and contributing to wound beds closure (Hickerson et al. (1994) [1]). Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

  12. Electrochemical methods for identification of irradiated liquid foods

    International Nuclear Information System (INIS)

    Xie Zongchuan; Ma Li; Shi Shuangping

    1988-01-01

    Samples of 14 kinds of wine, soy, vinegar, spirits, fruits in syrup, etc.were exposed to a Co-60 source. They responded with changes in electric potential and conductance. Especially, the electric potential in irradiated Shugan white spirits (made of sweet potato) was five times that in non-irradiated ones. Eighty five days after irradiation, the electric potential in the irradiated spirits dropped, but was still three times that in non- irradiated ones. The conductance in irradiated spirits was twenty percent more than that in non-irradiated ones. With addition of 0.1% H 2 O 2 to the spirits be- fore irradiation, the electric potential changed even larger

  13. Determination of material irradiation parameters. Required accuracies and available methods

    International Nuclear Information System (INIS)

    Cerles, J.M.; Mas, P.

    1978-01-01

    In this paper, the author reports some main methods to determine the nuclear parameters of material irradiation in testing reactor (nuclear power, burn-up, fluxes, fluences, ...). The different methods (theoretical or experimental) are reviewed: neutronics measurements and calculations, gamma scanning, thermal balance, ... The required accuracies are reviewed: they are of 3-5% on flux, fluences, nuclear power, burn-up, conversion factor, ... These required accuracies are compared with the real accuracies available which are at the present time of order of 5-20% on these parameters

  14. Determination of fuel irradiation parameters. Required accuracies and available methods

    International Nuclear Information System (INIS)

    Mas, P.

    1977-01-01

    This paper reports on the present point of some main methods to determine the nuclear parameters of fuel irradiation in testing reactors (nuclear power, burn up, ...) The different methods (theoretical or experimental) are reviewed: neutron measurements and calculations, gamma scanning, heat balance, ... . The required accuracies are reviewed: they are of 3-5 % on flux, fluences, nuclear power, burn-up, conversion factor. These required accuracies are compared with the real accuracies available which are the present time of order of 5-20 % on these parameters

  15. utilization of some physical methods for detection of some irradiated foods

    International Nuclear Information System (INIS)

    Mohammed, I.A.S

    2007-01-01

    the present investigation was carried out to establish a detection method for irradiated black pepper and marjoram using thermoluminescence (TL) and wheat, cinnamon and ginger using viscosity measurement. all samples were packed in polyethylene bags then irradiated at 5,10 and 15 kGy for black pepper, marjoram, cinnamon and ginger. wheat was irradiated at 1,2 and 3 kGy. all samples were stored for eight months at room temperature. results indicated that irradiation treatment caused markedly increasing in TL intensity for irradiated black pepper and marjoram while irradiation treatment decreased apparent viscosity of wheat flour, cinnamon and ginger powder, post irradiation and during storage. therefore, it could be concluded that the TL analysis can be used to detect irradiated black pepper and marjoram, also viscosity measurement can be used to detect irradiate wheat flour, cinnamon and ginger powder than non-irradiated ones after irradiation process and also during 8 months of storage at ambient temperature

  16. Kinetics of Phenol Degradation in Aqueous Solution Oxidized under Low Frequency Ultrasonic Irradiation

    Directory of Open Access Journals (Sweden)

    Marwan Marwan

    2014-06-01

    Full Text Available Phenol is categorized as a refractory pollutant and its presence in water stream is strictly limited according to the government regulation. The present study investigated the degra-dation of phenol in aqueous solution by the effect of ultrasound. The process took place in a 500 ml glass reactor equipped with magnetic stirring and irradiated by low frequency (28 kHz ultrasound from a horn type probe. Ultrasonic irradiation was found to enhance oxidation rates at ambient conditions, compared to other approaches. Optimum conditions were observed at a stirring speed of 400 rpm and temperature of 30 C in acidic solution. It was revealed that the phenol degradation was the first order kinetics with respect to phenol. A low value of the activation energy 6.04 kcal/mol suggested that diffusional steps were rate determining during the phenol decomposition. It also confirmed that phenol was mostly degraded in the film region and less occurred in the bulk solution.

  17. Effect of solute atoms on swelling in Ni alloys and pure Ni under He + ion irradiation

    Science.gov (United States)

    Wakai, E.; Ezawa, T.; Imamura, J.; Takenaka, T.; Tanabe, T.; Oshima, R.

    2002-12-01

    The effects of solute atoms on microstructural evolutions have been investigated using Ni alloys under 25 keV He + irradiation at 500 °C. The specimens used were pure Ni, Ni-Si, Ni-Co, Ni-Cu, Ni-Mn and Ni-Pd alloys with different volume size factors. The high number densities of dislocation loops about 1.5×10 22 m -3 were formed in the specimens irradiated to 1×10 19 ions/m 2, and they were approximately equivalent, except for Ni-Si. The mean size of loops tended to increase with the volume size factor of solute atoms. In a dose of 4×10 20 ions/m 2, the swelling was changed from 0.2% to 4.5%, depending on the volume size factors. The number densities of bubbles tended to increase with the absolute values of the volume size factor, and the swelling increased with the volume size factors. This suggests that the mobility of helium and vacancy atoms may be influenced by the interaction of solute atoms with them.

  18. Irradiation-induced precipitation and solute segregation in alloys. Fourth annual progress report, February 1, 1981-March 31, 1982

    International Nuclear Information System (INIS)

    Ardell, A.J.

    1982-04-01

    The studies of irradiation-induced solute segregation (IISS) and irradiation-induced precipitation (IIP) in Ni-Si and Pd-Fe alloys have been completed. Progress is reported for several other projects: irradiation damage in binary Pd-Cr, -Mn and -V alloys (15 at. %); IIP in Pd-Mo and Pd-W alloys; IIP in Pd-25 at. % Cr alloy; and irradiation damage effects in proton-bombarded metallic glasses (Ni-65 Zr, 40 Fe 40 Ni 14 P6B). 27 figures

  19. Perturbation method for periodic solutions of nonlinear jerk equations

    International Nuclear Information System (INIS)

    Hu, H.

    2008-01-01

    A Lindstedt-Poincare type perturbation method with bookkeeping parameters is presented for determining accurate analytical approximate periodic solutions of some third-order (jerk) differential equations with cubic nonlinearities. In the process of the solution, higher-order approximate angular frequencies are obtained by Newton's method. A typical example is given to illustrate the effectiveness and simplicity of the proposed method

  20. Chemical effects induced by dissolving γ-irradiated alkali halides in aqueous nitrate, permanganate and chromate solutions

    International Nuclear Information System (INIS)

    Phansalkar, V.K.; Bapat, L.; Ravishankar, D.

    1982-01-01

    Dissolution of γ-irradiated alkali halides in aqueous solutions of sodium nitrate, potassium permanganate and potassium chromate at neutral pH induces chemical changes leading to the formation of NO 2 - in nitrate, Mn(IV) and Cr(III) species in permanganate and chromate solutions, respectively. Further, the studies on nitrate and permanganate systems show that the amount of NO 2 - and Mn(IV) formed grows by increasing the dose of γ-irradiation of the salt and the amount of irradiated salt. Moreover, the extent of chemical changes effected by irradiated chlorides has been found to be more than that of bromides. The mesh size of the irradiated salt and the presence of scavengers like I - and methanol in the system, affects the yield of NO 2 - . (author)

  1. Formation of 32P-labelled Polyphosphates in Reactor-irradiated Solutions of Orthophosphate

    DEFF Research Database (Denmark)

    Fenger, Jørgen Folkvard; Pagsberg, Palle Bjørn

    1973-01-01

    yield increases with the concentration of the irradiated solution and varies in a complicated way with the pH. These observations and some experiments with addition of radical scavengers indicate that oxidation of the 32P-recoils by OH-radicals is an important step in the polymerization. It is suggested...... that the actual formation of a P&z.sbnd;O&z.sbnd;P bridge takes place as an addition of a Lewis acid to a lone pair of electrons on a phosphate ion....

  2. Viscosity of crystalline proteins in solution, when irradiated with 60 Co

    International Nuclear Information System (INIS)

    Bernardes, D.M.L.; Mastro, N.L. del

    1992-01-01

    In order to study 60 Co radiation effects on proteins, an aqueous solution of bovine crystalline was irradiated with doses from O to 25,000 Gy. Changes in viscosity were followed whether in the presence or absence of radiation response modifiers: glutathione (GSH), amino ethyl isothiourea (AET), mercapto ethyl alanine (MEA) e dimethyl sulfoxide (DMSO). Viscosity data at different temperature revealed that aggregate formation was the predominant process induced by radiation. The results showed also that in presence of those substances the radiation effects was diminished. (author)

  3. Effects of point defect trapping and solute segregation on irradiation-induced swelling and creep

    International Nuclear Information System (INIS)

    Mansur, L.K.

    1978-01-01

    The theory of irradiation swelling and creep, generalized to include impurity trapping of point defects and impurity-induced changes in sink efficiencies for point defects, is reviewed. The mathematical framework is developed and significant results are described. These include the relation between vacancy and interstitial trapping and the effectiveness of trapping as compared to segregation-induced changes in sink efficiencies in modifying void nucleation, void growth, and creep. Current understanding is critically assessed. Several areas requiring further development are identified. In particular those given special attention are the treatment of nondilute solutions and the consequences of current uncertainties in fundamental materials properties whose importance has been identified using the theory

  4. Detection of irradiated components in flavour blends composed of non-irradiated species herbs and vegetable seasonings by thermoluminescence method

    International Nuclear Information System (INIS)

    Malec-Czechowska, K.; Stachowicz, W.

    2003-01-01

    The results of experiments on the detection of irradiated component in commercial flavour blends composed of a mixture of non-irradiated spices, herbs and seasonings are presented. A method based on the thermoluminescence measurements on silicate materials isolated from blends has been adapted. It has been proved that by applying of this technique it is possible to detect 0.95% by weight of paprika, irradiated with a dose of 7 kGy, which was a minor component of non-irradiated flavour blends. (author)

  5. Systematization of types and methods of radiation therapy methods and techniques of irradiation of patients

    International Nuclear Information System (INIS)

    Vajnberg, M.Sh.

    1991-01-01

    The paper is concerned with the principles of systematization and classification of types and methods of radiation therapy, approaches to the regulation of its terminology. They are based on the distinction of the concepts of radiation therapy and irradiation of patients. The author gives a consice historical review of improvement of the methodology of radiation therapy in the course of developing of its methods and facilities. Problems of terminology are under discussion. There is a table of types and methods of radiation therapy, methods and techniques of irradiation. In the appendices one can find a table of typical legends and examples of graphic signs to denote methods of irradiation. Potentialities of a practical use of the system are described

  6. Discrete ordinates solution of coupled conductive radiative heat transfer in a two-layer slab with Fresnel interfaces subject to diffuse and obliquely collimated irradiation

    International Nuclear Information System (INIS)

    Muresan, Cristian; Vaillon, Rodolphe; Menezo, Christophe; Morlot, Rodolphe

    2004-01-01

    The coupled conductive radiative heat transfer in a two-layer slab with Fresnel interfaces subject to diffuse and obliquely collimated irradiation is solved. The collimated and diffuse components problems are treated separately. The solution for diffuse radiation is obtained by using a composite discrete ordinates method and includes the development of adaptive directional quadratures to overcome the difficulties usually encountered at the interfaces. The complete radiation numerical model is validated against the predictions obtained by using the Monte Carlo method

  7. U-turn type continuous irradiation method and device for radiation-irradiated capsule

    International Nuclear Information System (INIS)

    Kikuchi, Takayuki.

    1997-01-01

    A capsule to be irradiated is moved while being rotated in one of conveying shafts disposed in a reactor to conduct irradiation treatment. Then, the irradiated capsule is made U-turn in the reactor, inserted to the other conveying shaft and moved while being rotated to conduct irradiation treatment again, and then transported out of the reactor. The device comprises a rotational conveying shaft for moving the irradiated capsule while rotating it, a conveying gear for U-turning the irradiated capsule in the reactor and inserting it to the conveying shaft and a driving mechanism for synchronously rotating the conveying gear relative to the conveying shaft at a constant ratio. Mechanical time loss and manual operation time loss can be reduced upon loading and taking up of the irradiated capsule. Then, the amount of irradiation treatment per unit time is increased, and an optional neutron irradiation amount can be obtained thereby enabling to reduce operator's radiation exposure. (N.H.)

  8. Development of fluorescent, oscillometric and photometric methods to determine absorbed dose in irradiated fruits and nuts

    International Nuclear Information System (INIS)

    Kovacs, A.; Foeldiak, G.; Hargittai, P.; Miller, S.D.

    2001-01-01

    To ensure suitable quality control at food irradiation technologies and for quarantine authorities, simple routine dosimetry methods are needed for absorbed dose control. Taking into account the requirements at quarantine locations these methods would require nondestructive analysis for repeated measurements. Different dosimetry systems with different analytical evaluation methods have been tested and/or developed for absorbed dose measurements in the dose range of 0.1-10 kGy. In order to use the well accepted ethanolmonochlorobenzene dosimeter solution and the recently developed aqueous alanine solution in small volume sealed vials, a new portable, digital, and programmable oscillometric reader was developed. To make use of the availability of the very sensitive fluorimetric evaluation method, liquid and solid inorganic and organic dosimetry systems were developed for dose control using a new routine, portable, and computer controlled fluorimeter. Absorption or transmission photometric methods were also applied for dose measurements of solid or liquid phase dosimeter systems containing radiochromic dye agents, which change colour upon irradiation. (author)

  9. Development of decomposition method for chlorofluorocarbon (CFC) solvent by irradiation

    International Nuclear Information System (INIS)

    Shimokawa, Toshinari; Nakagawa, Seiko

    1995-01-01

    CFC is chemically and thermally stable, and almost harmless to human body, therefore, it has been used widely for various industries, in particular as the heat media for air conditioners and the washing agent for semiconductors and printed circuit substrates. In 1974, it was pointed out that CFC causes the breakdown of ozone layer, and the ozone hole was found, consequently, it was decided to limit its use, and to prohibit the production of specific CFC. The development of the decomposition treatment technology for the CFC now in use, which is friendly to the global environment including mankind and ozone layer, is strongly desired. Recently, the authors have examined the decomposition treatment method for specific CFC solvents by irradiation, and obtained the interesting knowledge. For the experiment, the CFC 113 was used, and its chemical structure is shown. The experimental method is explained. As the results, the effect of hydroxide ions, the decomposition products such as CFC 123, and the presumption of the mechanism of the chain dechlorination reaction of CFC 113 are reported. The irradiation decomposition method was compared with various other methods, and the cost of treatment is high. The development for hereafter is mentioned. (K.I.)

  10. Solid solutions of gadolinium doped zinc oxide nanorods by combined microwave-ultrasonic irradiation assisted crystallization

    Science.gov (United States)

    Kiani, Armin; Dastafkan, Kamran; Obeydavi, Ali; Rahimi, Mohammad

    2017-12-01

    Nanocrystalline solid solutions consisting of un-doped and gadolinium doped zinc oxide nanorods were fabricated by a modified sol-gel process utilizing combined ultrasonic-microwave irradiations. Polyvinylpyrrolidone, diethylene glycol, and triethylenetetramine respectively as capping, structure directing, and complexing agents were used under ultrasound dynamic aging and microwave heating to obtain crystalline nanorods. Crystalline phase monitoring, lattice parameters and variation, morphology and shape, elemental analysis, functional groups, reducibility, and the oxidation state of emerged species were examined by PXRD, FESEM, TEM, EDX, FTIR, micro Raman, H2-TPR, and EPR techniques. Results have verified that irradiation mechanism of gelation and crystallization reduces the reaction time, augments the crystal quality, and formation of hexagonal close pack structure of Wurtzite morphology. Besides, dissolution of gadolinium within host lattice involves lattice deformation, unit cell distortion, and angular position variation. Structure related shape and growth along with compositional purity were observed through microscopic and spectroscopic surveys. Furthermore, TPR and EPR studies elucidated more detailed behavior upon exposure to the exerted irradiations and subsequent air-annealing including the formed oxidation states and electron trapping centers, presence of gadolinium, zinc, and oxygen disarrays and defects, as well as alteration in the host unit cell via gadolinium addition.

  11. Methods of thallium-201 preparation from proton irradiated thallium targets

    International Nuclear Information System (INIS)

    Kozlova, M.D.; Sevast'yanova, A.S.; Malinin, A.B.; Kurenkov, N.V.

    1989-01-01

    Two methods of thallium-201 preparation from Tl-targets irradiated by protons: oxidation-extraction (1) and extraction (2) - are developed. At first radioactive lead is separated from the target material - thallium macroquantities during ∼32 hours, then thallium-201 was separated from residual activity of lead radioisotopes and transformed it into the necessary chemical formula. The 1st and 2nd methods differ from each other by the 1st stage of target retreatment; only extraction was used to separate radioactive lead in the 2nd method. The target was solved in H 2 SO 4 . The 1st method permits to separate thallium-201 with chemical yield not less than 90 %, the 2nd one - higher than 95 %. Volumetric activity of thallium-201 prepared is more than 55 MBq/ml. 5 refs

  12. Method for dose calculation in intracavitary irradiation of endometrical carcinoma

    International Nuclear Information System (INIS)

    Zevrieva, I.F.; Ivashchenko, N.T.; Musapirova, N.A.; Fel'dman, S.Z.; Sajbekov, T.S.

    1979-01-01

    A method for dose calculation for the conditions of intracavitary gamma therapy of endometrial carcinoma using spherical and linear 60 Co sources was elaborated. Calculations of dose rates for different amount and orientation of spherical radiation sources and for different planes were made with the aid of BEhSM-4M computer. Dosimet were made with the aid of BEhSM-4M computer. Dosimetric study of dose fields was made using a phantom imitating the real conditions of irradiation. Discrepancies between experimental and calculated values are within the limits of the experiment accuracy

  13. Determination of solute descriptors by chromatographic methods

    International Nuclear Information System (INIS)

    Poole, Colin F.; Atapattu, Sanka N.; Poole, Salwa K.; Bell, Andrea K.

    2009-01-01

    The solvation parameter model is now well established as a useful tool for obtaining quantitative structure-property relationships for chemical, biomedical and environmental processes. The model correlates a free-energy related property of a system to six free-energy derived descriptors describing molecular properties. These molecular descriptors are defined as L (gas-liquid partition coefficient on hexadecane at 298 K), V (McGowan's characteristic volume), E (excess molar refraction), S (dipolarity/polarizability), A (hydrogen-bond acidity), and B (hydrogen-bond basicity). McGowan's characteristic volume is trivially calculated from structure and the excess molar refraction can be calculated for liquids from their refractive index and easily estimated for solids. The remaining four descriptors are derived by experiment using (largely) two-phase partitioning, chromatography, and solubility measurements. In this article, the use of gas chromatography, reversed-phase liquid chromatography, micellar electrokinetic chromatography, and two-phase partitioning for determining solute descriptors is described. A large database of experimental retention factors and partition coefficients is constructed after first applying selection tools to remove unreliable experimental values and an optimized collection of varied compounds with descriptor values suitable for calibrating chromatographic systems is presented. These optimized descriptors are demonstrated to be robust and more suitable than other groups of descriptors characterizing the separation properties of chromatographic systems.

  14. Determination of solute descriptors by chromatographic methods.

    Science.gov (United States)

    Poole, Colin F; Atapattu, Sanka N; Poole, Salwa K; Bell, Andrea K

    2009-10-12

    The solvation parameter model is now well established as a useful tool for obtaining quantitative structure-property relationships for chemical, biomedical and environmental processes. The model correlates a free-energy related property of a system to six free-energy derived descriptors describing molecular properties. These molecular descriptors are defined as L (gas-liquid partition coefficient on hexadecane at 298K), V (McGowan's characteristic volume), E (excess molar refraction), S (dipolarity/polarizability), A (hydrogen-bond acidity), and B (hydrogen-bond basicity). McGowan's characteristic volume is trivially calculated from structure and the excess molar refraction can be calculated for liquids from their refractive index and easily estimated for solids. The remaining four descriptors are derived by experiment using (largely) two-phase partitioning, chromatography, and solubility measurements. In this article, the use of gas chromatography, reversed-phase liquid chromatography, micellar electrokinetic chromatography, and two-phase partitioning for determining solute descriptors is described. A large database of experimental retention factors and partition coefficients is constructed after first applying selection tools to remove unreliable experimental values and an optimized collection of varied compounds with descriptor values suitable for calibrating chromatographic systems is presented. These optimized descriptors are demonstrated to be robust and more suitable than other groups of descriptors characterizing the separation properties of chromatographic systems.

  15. Effect of a magnetic field on the fluorescence produced in irradiated anthracene solutions

    International Nuclear Information System (INIS)

    Dixon, R.S.; Sargent, F.P.; Lopata, V.J.; Gardy, E.M.; Brocklehurst, B.

    1977-01-01

    The effect of an applied magnetic field on the fluorescence from radiolytic ion recombination has been studied for anthracene in some hydrocarbon solvents. In pulse-irradiated anthracene in squalane, the fluorescence intensity following the pulse increases as a function of applied magnetic field in the range studied. At a constant magnetic field strength, the field-induced enhancement of the fluorescence intensity varies with time after the pulse. At high field strengths the enhancement reaches a maximum about 50 ns after the pulse. Similar effects are observed in cyclohexane but the enhancement is smaller than that in squalane. In benzene solutions the effect is extremely small. These findings are confirmed by observations in continuously gamma-irradiated solutions. 9,10-Dimethylanthracene gives a larger enhancement and anthracene-d 10 a smaller enhancement than the parent anthracene at high fields. The results are in general agreement with recent theoretical predictions based on the effect of a magnetic field on the loss of spin correlation of geminate ions pairs prior to recombination

  16. Dosimetric characteristics of aqueous solution of crystal violet for applications in food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Khan, H M; Naz, Shagufta; Tabassum, Safia [Peshawar University, Peshawar (Pakistan). Radiation Chemistry Laboratory, National Centre of Excellence in Physical Chemistry

    2011-07-15

    Aqueous solution of crystal violet has been evaluated spectrophotometrically as a gamma-ray chemical dosimeter. The response of the chemical dosimetric system has also been investigated under different environmental conditions, such as light and temperature. In the present study the response has been measured at two wavelengths; 588 nm ({lambda}{sub max} of the irradiated solution) and 500 nm. The response of the crystal violet dosimeter was linear in the dose range of 50-550 Gy at pH 5.6 when absorption measurements were made at 588 and 500 nm. The response of the crystal violet dosimeter during post-irradiation storage at room temperature in dark showed slight decrease in absorbance at 588 and 510 nm but the response was almost stable at 460 nm. For higher doses, the change in the response was greater as compared to the low doses. Post-irradiation stability during diffused sunlight showed significant decrease in the response for higher dose at 588 and 510 nm and slower decrease in the response for lower dose at the above mentioned wavelengths. However the response was almost stable up to 97 days at 460 nm for higher and lower doses. At 4 deg C, the decrease in the absorbance was slower at 588 and 510 nm while the response was almost constant at 460 nm. At higher temperatures, such as 40 deg C, the decrease in the absorbance was greater at 588 and 510 nm while at 460 nm the absorbance was almost constant for about 3 months. (author)

  17. Dosimetric characteristics of aqueous solution of crystal violet for applications in food irradiation

    International Nuclear Information System (INIS)

    Khan, H.M.; Shagufta Naz; Safia Tabassum

    2011-01-01

    Aqueous solution of crystal violet has been evaluated spectrophotometrically as a gamma-ray chemical dosimeter. The response of the chemical dosimetric system has also been investigated under different environmental conditions, such as light and temperature. In the present study the response has been measured at two wavelengths; 588 nm (λ max of the irradiated solution) and 500 nm. The response of the crystal violet dosimeter was linear in the dose range of 50-550 Gy at pH 5.6 when absorption measurements were made at 588 and 500 nm. The response of the crystal violet dosimeter during post-irradiation storage at room temperature in dark showed slight decrease in absorbance at 588 and 510 nm but the response was almost stable at 460 nm. For higher doses, the change in the response was greater as compared to the low doses. Post-irradiation stability during diffused sunlight showed significant decrease in the response for higher dose at 588 and 510 nm and slower decrease in the response for lower dose at the above mentioned wavelengths. However the response was almost stable up to 97 days at 460 nm for higher and lower doses. At 4 deg C, the decrease in the absorbance was slower at 588 and 510 nm while the response was almost constant at 460 nm. At higher temperatures, such as 40 deg C, the decrease in the absorbance was greater at 588 and 510 nm while at 460 nm the absorbance was almost constant for about 3 months. (author)

  18. Variation Iteration Method for The Approximate Solution of Nonlinear ...

    African Journals Online (AJOL)

    In this study, we considered the numerical solution of the nonlinear Burgers equation using the Variational Iteration Method (VIM). The method seeks to examine the convergence of solutions of the Burgers equation at the expense of the parameters x and t of which the amount of errors depends. Numerical experimentation ...

  19. expansion method and travelling wave solutions for the perturbed ...

    Indian Academy of Sciences (India)

    Abstract. In this paper, we construct the travelling wave solutions to the perturbed nonlinear. Schrödinger's equation (NLSE) with Kerr law non-linearity by the extended (G /G)-expansion method. Based on this method, we obtain abundant exact travelling wave solutions of NLSE with. Kerr law nonlinearity with arbitrary ...

  20. The functional variable method for finding exact solutions of some ...

    Indian Academy of Sciences (India)

    Abstract. In this paper, we implemented the functional variable method and the modified. Riemann–Liouville derivative for the exact solitary wave solutions and periodic wave solutions of the time-fractional Klein–Gordon equation, and the time-fractional Hirota–Satsuma coupled. KdV system. This method is extremely simple ...

  1. Graft copolymerization of water soluble mixed monomers onto polyethylene by the pre-irradiation method

    International Nuclear Information System (INIS)

    Long Fu; Tang Liming; Zhao Jin; Gao Zhenyong

    1993-01-01

    Grafting of water soluble mixed monomers of acrylic acid (AA)/acrylamide (Am) and acrylic acid/methacrylic acid (MA) onto polyethylene film by the pre-irradiation grafting method was investigated. The results showed that the grafting proceeded successfully with the adding of ferric salt in the solution. In the case of AA/Am system, a synergistic effect was noticed. In the case of AA/MA system, the graft percent increased with the increase in the concentration of MA in the feed ratio. Furthermore, the effects of monomer concentration, radiation dose and temperature on the grafting were also studied

  2. Approximate solution methods in engineering mechanics

    International Nuclear Information System (INIS)

    Boresi, A.P.; Cong, K.P.

    1991-01-01

    This is a short book of 147 pages including references and sometimes bibliographies at the end of each chapter, and subject and author indices at the end of the book. The test includes an introduction of 3 pages, 29 pages explaining approximate analysis, 41 pages on finite differences, 36 pages on finite elements, and 17 pages on specialized methods

  3. Evaluation of element migration from food plastic packagings into simulated solutions using radiometric method

    International Nuclear Information System (INIS)

    Soares, Eufemia Paez; Saiki, Mitiko; Wiebeck, Helio

    2005-01-01

    In the present study a radiometric method was established to determine the migration of elements from food plastic packagings to a simulated acetic acid solution. This radiometric method consisted of irradiating plastic samples with neutrons at IEA-R1 nuclear reactor for a period of 16 hours under a neutron flux of 10 12 n cm -2 s -1 and, then to expose them to the element migration into a simulated solution. The radioactivity of the activated elements transferred to the solutions was measured to evaluate the migration. The experimental conditions were: time of exposure of 10 days at 40 deg C and 3% acetic acid solution was used as simulated solution, according to the procedure established by the National Agency of Sanitary Monitoring (ANVISA). The migration study was applied for plastic samples from soft drink and juice packagings. The results obtained indicated the migration of elements Co, Cr and Sb. The advantage of this methodology was no need to analyse the blank of simulantes, as well as the use of high purity simulated solutions. Besides, the method allows to evaluate the migration of the elements into the food content instead of simulated solution. The detention limits indicated high sensitivity of the radiometric method. (author)

  4. Pretreatment of Cellulose By Electron Beam Irradiation Method

    Science.gov (United States)

    Jusri, N. A. A.; Azizan, A.; Ibrahim, N.; Salleh, R. Mohd; Rahman, M. F. Abd

    2018-05-01

    Pretreatment process of lignocellulosic biomass (LCB) to produce biofuel has been conducted by using various methods including physical, chemical, physicochemical as well as biological. The conversion of bioethanol process typically involves several steps which consist of pretreatment, hydrolysis, fermentation and separation. In this project, microcrystalline cellulose (MCC) was used in replacement of LCB since cellulose has the highest content of LCB for the purpose of investigating the effectiveness of new pretreatment method using radiation technology. Irradiation with different doses (100 kGy to 1000 kGy) was conducted by using electron beam accelerator equipment at Agensi Nuklear Malaysia. Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD) analyses were studied to further understand the effect of the suggested pretreatment step to the content of MCC. Through this method namely IRR-LCB, an ideal and optimal condition for pretreatment prior to the production of biofuel by using LCB may be introduced.

  5. Review of control rod calibration methods for irradiated AGRs

    Energy Technology Data Exchange (ETDEWEB)

    Telford, A. R.R.

    1975-10-15

    Methods of calibrating control rods with particular reference to irradiated CAGR are surveyed. Some systematic spatial effects are found and an estimate of their magnitude made. It is concluded that control rod oscillation provides a promising method of calibrating rods at power which is as yet untried on CAGR. Also the rod drop using inverse kinetics provides a rod calibration but spatial effects may be large and these would be difficult to correct theoretically. The pulsed neutron technique provides a calibration route with small errors due to spatial effects provided a suitable K-tube can be developed. The xenon transient method is shown to have spatial effects which have not needed consideration in earlier reactors but which in CAGR would need very careful evaluation.

  6. Method for separation of Cs from acid solution dissolving radionuclides and microanalysis of solution with ICP-AES

    International Nuclear Information System (INIS)

    Kanazawa, Toru; Hidaka, Akihide; Kudo, Tamotsu; Nakamura, Takehiko; Fuketa, Toyoshi

    2004-06-01

    The VEGA (Verification Experiments of radionuclides Gas/Aerosol release) program is being performed at JAERI to understand mechanisms of radionuclides release from irradiated fuel during severe accidents. As a part of evaluation in the program, the mass balances of released and deposited FP (Fission Products) onto the test apparatus are estimated from gamma ray measurement for acid solution leached from the apparatus, but short-life nuclides are difficult to be measured because those in the VEGA fuel have been mostly depleted due to cooling for several years. Moreover, the radionuclides without emitting gamma rays and very small quantity of elements cannot be quantified by gamma ray measurement. Therefore, a microanalysis by ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectrometry) for the acid solution leached from VEGA apparatuses is being applied to evaluate the released and deposited masses for those elements. Since Cs-134 and -137, which are major FP dissolved in the solution, have high intensity of gamma ray spectrum, they have to be removed from the solution before the microanalysis in order to avoid contamination of ICP system and to decrease exposure to gamma ray. In this report, methods for separation of Cs from acid solution were reviewed and the applicability of them to the ICP-AES analysis was discussed. The method for Cs separation using the inorganic ion exchanger, AMP (Ammonium Molybdate Phosphate) was applied to the solutions of cold and hot test and the effectiveness was examined. The results showed that more than 99.9% of Cs could be removed from the test solutions, and once removed Sb by AMP was recovered by using a complexing agent such as citric acid. Next, the method was applied to an acid solution leached from VEGA-3 apparatus, and ICP-AES analysis was performed for it. The analysis showed that amount of U, Sr and Zr were successfully quantified. Most of elements to be analyzed were measurable except for Sb, Ag and Sn, although

  7. Influence of water and salt solutions on UVB irradiation of normal skin and psoriasis

    International Nuclear Information System (INIS)

    Boer, J.; Schothorst, A.A.; Boom, B.; Suurmond, D.; Hermans, J.

    1982-01-01

    The influence of tap-water (TW) and salt solutions on the minimal erythema dose (MED) was investigated for normal human skin and uninvolved skin of psoriasis patients. MED (UVB) determinations on the forearm revealed that: (1) the MED definitely decreases whenever the arm is immersed in TW or NaCl solutions with a low concentration (4%) prior to UVB exposure, whereas almost saturated NaCl solution (26%), as well as locum Dead Sea water (LDSW), do not produce a change in the MED, and (2) the decrease in MED obtained by wetting the skin with TW was no longer present when the skin was allowed to dry for 20 min. A decrease in water uptake by skin (in vivo) and by callus (in vitro) was found as the salt concentration of the external solution increased. It is proposed that water taken up by the skin plays an important role in the sensitivity of the skin to UVB exposure. Bathing in TW or 4% NaCl prior to UVB exposure offered a slight to moderate improvement in psoriasis over UVB irradiation alone. Finally, it was shown that there is no obvious difference in clearance of the psoriatic skin between a bath in TW, 4% NaCl, or LDSW prior to UVB exposure. (orig.)

  8. Preparation of vinyl acetate grafted natural rubber by irradiation method

    Energy Technology Data Exchange (ETDEWEB)

    Porntrairat, A.; Pattamaprom, C. [Center of Excellence on Natural Rubber Technology, Department of Chemical Engineering, Faculty of Engineering, Thammasat University, Pathumthani 12120 (Thailand)

    2016-03-09

    Improvement in properties of natural rubber could be done by several methods. In this research, gamma radiation technique, which is simple, accurate, easy to control and clean, was applied to enhance the properties of natural rubber (NR) in latex state. The purpose of this research is to study the appropriate condition for preparing grafted natural rubber latex by using irradiation method. Vinyl acetate monomers (VAc) were grafted onto natural rubber latex (NR-g-PVAc) at 0-10 kGys by gamma radiation from Cobalt-60 source at room temperature. Physical properties of grafted natural rubber such as chloroform number, swelling ratio and gel content were measured. The VAc content of NR-g-PVAc was investigated by titration and visualized by FTIR spectroscopy. The FTIR spectra of NR-g-PVAc prepared at 0-10 kGys showed characteristic peaks of the vinyl acetate confirming that VAc could be grafted onto natural rubber molecular chains effectively under appropriate irradiation conditions. From the result, radiation grafting was found to be a useful technique for grafting of vinyl acetate onto natural rubber.

  9. Kinetic equation solution by inverse kinetic method

    International Nuclear Information System (INIS)

    Salas, G.

    1983-01-01

    We propose a computer program (CAMU) which permits to solve the inverse kinetic equation. The CAMU code is written in HPL language for a HP 982 A microcomputer with a peripheral interface HP 9876 A ''thermal graphic printer''. The CAMU code solves the inverse kinetic equation by taking as data entry the output of the ionization chambers and integrating the equation with the help of the Simpson method. With this program we calculate the evolution of the reactivity in time for a given disturbance

  10. Dosimetry and irradiation methods for the ANSTO gamma technology research irradiator (GATRI)

    International Nuclear Information System (INIS)

    Izard, M.E.

    1988-07-01

    The Australian Nuclear Science and Technology Organisation's gamma technology research irradiator (GATRI) at Lucas Heights, New South Wales, has been modified for use as a research and small-scale commercial irradiation facility to be available to government agencies and private industry for the technical and economic evaluation of irradiation processing. The new source rack was designed around existing mechanical components to optimise the limited space available within the irradiation cell. Irradiation parameters investigated during commissioning included the effect of source-to-target distance on relative dose rates within targets of the same density; effect of density on dose-rate distribution within targets irradiated at the same distance from the source; and the contribution of transit dose to low absorbed doses as the source is raised and lowered. The efficiency of the irradiator was determined for various target densities and overdose ratios

  11. Approximate solution fuzzy pantograph equation by using homotopy perturbation method

    Science.gov (United States)

    Jameel, A. F.; Saaban, A.; Ahadkulov, H.; Alipiah, F. M.

    2017-09-01

    In this paper, Homotopy Perturbation Method (HPM) is modified and formulated to find the approximate solution for its employment to solve (FDDEs) involving a fuzzy pantograph equation. The solution that can be obtained by using HPM is in the form of infinite series that converge to the actual solution of the FDDE and this is one of the benefits of this method In addition, it can be used for solving high order fuzzy delay differential equations directly without reduction to a first order system. Moreover, the accuracy of HPM can be detected without needing the exact solution. The HPM is studied for fuzzy initial value problems involving pantograph equation. Using the properties of fuzzy set theory, we reformulate the standard approximate method of HPM and obtain the approximate solutions. The effectiveness of the proposed method is demonstrated for third order fuzzy pantograph equation.

  12. CFD code verification and the method of manufactured solutions

    International Nuclear Information System (INIS)

    Pelletier, D.; Roache, P.J.

    2002-01-01

    This paper presents the Method of Manufactured Solutions (MMS) for CFD code verification. The MMS provides benchmark solutions for direct evaluation of the solution error. The best benchmarks are exact analytical solutions with sufficiently complex solution structure to ensure that all terms of the differential equations are exercised in the simulation. The MMS provides a straight forward and general procedure for generating such solutions. When used with systematic grid refinement studies, which are remarkably sensitive, the MMS provides strong code verification with a theorem-like quality. The MMS is first presented on simple 1-D examples. Manufactured solutions for more complex problems are then presented with sample results from grid convergence studies. (author)

  13. Optimisation-Based Solution Methods for Set Partitioning Models

    DEFF Research Database (Denmark)

    Rasmussen, Matias Sevel

    The scheduling of crew, i.e. the construction of work schedules for crew members, is often not a trivial task, but a complex puzzle. The task is complicated by rules, restrictions, and preferences. Therefore, manual solutions as well as solutions from standard software packages are not always su......_cient with respect to solution quality and solution time. Enhancement of the overall solution quality as well as the solution time can be of vital importance to many organisations. The _elds of operations research and mathematical optimisation deal with mathematical modelling of di_cult scheduling problems (among...... other topics). The _elds also deal with the development of sophisticated solution methods for these mathematical models. This thesis describes the set partitioning model which has been widely used for modelling crew scheduling problems. Integer properties for the set partitioning model are shown...

  14. Nonclassical pseudospectral method for the solution of brachistochrone problem

    International Nuclear Information System (INIS)

    Alipanah, A.; Razzaghi, M.; Dehghan, M.

    2007-01-01

    In this paper, nonclassical pseudospectral method is proposed for solving the classic brachistochrone problem. The brachistochrone problem is first formulated as a nonlinear optimal control problem. Properties of nonclassical pseudospectral method are presented, these properties are then utilized to reduce the computation of brachistochrone problem to the solution of algebraic equations. Using this method, the solution to the brachistochrone problem is compared with those in the literature

  15. Direct observation of solute segregation to voids in a fast-neutron irradiated (Mo/1.0 at. % Ti alloy

    International Nuclear Information System (INIS)

    Wagner, A.; Seidman, D.N.

    1978-11-01

    The atom-probe field-ion microscope was used to study segregation effects to voids in a Mo--Ti alloy which had been irradiated with fast neutrons. The Ti does not segregate significantly to voids, concentration of Ti in solid solution and the spacial distribution of Ti was not affected by irradiation, carbon was not detected, resolution of TiC or MoC precipitates did not occur

  16. Effects of Si3+ and H+ Irradiation on Tungsten Evaluated by Internal Friction Method

    International Nuclear Information System (INIS)

    Hu Jing; Wang Xianping; Fang Qianfeng; Liu Changsong; Zhang Yanwen; Zhao Ziqiang

    2013-01-01

    Effects of Si 3+ and H + irradiation on tungsten were investigated by internal friction (IF) technique. Scanning electron microscope (SEM) analysis revealed that sequential dual Si+H irradiation resulted in more serious damage than single Si irradiation. After irradiation, the IF background was significantly enhanced. Besides, two obvious IF peaks were initially found in temperature range of 70∼330 K in the sequential Si+H irradiated tungsten sample. The mechanism of increased IF background for the irradiated samples was suggested to originate from the high density dislocations induced by ion irradiation. On the other hand, the relaxation peak P L and non-relaxation peak P H in the Si+H irradiated sample were ascribed to the interaction process of hydrogen atoms with mobile dislocations and transient processes of hydrogen redistribution, respectively. The obtained experimental results verified the high sensitivity of IF method on the irradiation damage behaviors in nuclear materials

  17. Biosythesis of Silver Nanoparticles using Putri Malu (Mimosa pudica Leaves Extract and Microwave Irradiation Method

    Directory of Open Access Journals (Sweden)

    Is Fatimah

    2016-11-01

    Full Text Available In this paper, the biosynthesis of silver nanoparticles (AgNPs using Mimosa pudica extract is discussed. Mimosa pudica leaves extract using water as solvent was used as bio-reductor to an aqueous solution of silver nitrate (AgNO3 and in order to accelerate the reduction, microwave irradiation method was applied. The AgNPs obtained were characterized using UV-Vis spectrophotometry, FTIR spectrophotometry, XRD, SEM-EDX, and particle size analysis based on dynamic scattering method. Effect of preparation method to the formation of AgNPs is also evaluated in antibacterial activity towards E.coli and P. aeruginosa. Rapid and ecofriendly biosynthesis of stable silver nanoparticles was observed in this study. The characterization results and antibacterial assay indicated the uniform and smaller particle size of AgNPs obtained by using microwave method and positively enhance the antibacterial activity against tested bacteria.

  18. A simple method for identification of irradiated spices

    International Nuclear Information System (INIS)

    Behere, A.; Desai, S.R.P.; Nair, P.M.; Rao, S.M.D.

    1992-01-01

    Thermoluminescence (TL) properties of curry powder, a salt containing spice mixture, and three different ground spices, viz, chilli, turmeric and pepper, were compared with TL of table salt. The spices other than curry powder, did not exhibit characteristic TL in the absence of salt. Therefore studies were initiated to develop a simple and reliable method using common salt for distinguishing irradiated spices (10 kGy) from unirradiated ones under normal conditions of storage. Common salt exhibited a characteristic TL glow at 170 o C. However, when present in curry powder, the TL glow of salt showed a shift to 208 o C. It was further observed that upon storage up to 6 months, the TL of irradiated curry powder retained about 10% of the original intensity and still could be distinguished from the untreated samples. From our results it is evident that common salt could be used as an indicator either internally or externally in small sachets for incorporating into prepacked spices. (author)

  19. A simple method for identification of irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Behere, A; Desai, S R.P.; Nair, P M [Bhabha Atomic Research Centre, Bombay (India). Food Technology and Enzyme Engineering Div.; Rao, S M.D. [Bhabha Atomic Research Centre, Bombay (India). Technical Physics and Prototype Engineering Div.

    1992-07-01

    Thermoluminescence (TL) properties of curry powder, a salt containing spice mixture, and three different ground spices, viz, chilli, turmeric and pepper, were compared with TL of table salt. The spices other than curry powder, did not exhibit characteristic TL in the absence of salt. Therefore studies were initiated to develop a simple and reliable method using common salt for distinguishing irradiated spices (10 kGy) from unirradiated ones under normal conditions of storage. Common salt exhibited a characteristic TL glow at 170{sup o}C. However, when present in curry powder, the TL glow of salt showed a shift to 208{sup o}C. It was further observed that upon storage up to 6 months, the TL of irradiated curry powder retained about 10% of the original intensity and still could be distinguished from the untreated samples. From our results it is evident that common salt could be used as an indicator either internally or externally in small sachets for incorporating into prepacked spices. (author).

  20. Method for monitoring irradiated nuclear fuel using cerenkov radiation

    International Nuclear Information System (INIS)

    Caldwell, J.T.; Dowdy, E.J.; Nicholson, N.

    1983-01-01

    A method is provided for monitoring irradiated nuclear fuel inventories located in a water-filled storage pond wherein the intensity of the cerenkov radiation emitted from the water in the vicinity of the nuclear fuel is measured. This intensity is then compared with the expected intensity for nuclear fuel having a corresponding degree of irradiation exposure and time period after removal from a reactor core. Where the nuclear fuel inventory is located in an assembly having fuel pins or rods with intervening voids, the cerenkov light intensity measurement is taken at selected bright spots corresponding to the water-filled interstices of the assembly in the water storage, the waterfilled interstices acting as cerenkov light channels so as to reduce cross-talk. On-line digital analysis of an analog video signal is possible, or video tapes may be used for later measurement using a video editor and an electrometer. Direct measurement of the cerenkov radiation intensity also is possible using spot photometers pointed at the assembly

  1. Degradation of a monoazo dye Alizarin Yellow GG in aqueous solutions by gamma irradiation: Decolorization and biodegradability enhancement

    International Nuclear Information System (INIS)

    Sun, Weihua; Chen, Lujun; Tian, Jinping; Wang, Jianlong; He, Shijun

    2013-01-01

    The irradiation-induced degradation of an azo dye, Alizarin Yellow GG (AY-GG), was investigated in aqueous solution under gamma irradiation using a 60 Cobalt source at a dose rate of 113 Gy/min. The decolorization percentage of AY-GG reached 65% when its initial concentration was 100 mg/l and the absorbed dose was 9 kGy. The decolorization process could be described by first-order kinetic equation. In addition, specific oxygen uptake rate (SOUR, mg O 2 (g MLVSS) −1 h −1 ) of activated sludge using the irradiated azo dye solutions was 8.1 mg O 2 (g MLVSS) −1 h −1 after 9 kGy irradiation, indicating that the biodegradability of AY-GG could be enhanced by 30%. However, toxic intermediates including heterocyclic aromatic amines and cyanides were detected during the irradiation process, which inhibited the complete biological degradation of azo dye. Fortunately, the inhibition could be eliminated by further irradiation. The azo dye solution became amenable to biodegradation and can be further treated by biological treatment process. - Highlights: ► Decolorization process by radiation conformed to first-order kinetics. ► Biodegradability of AY-GG could be enhanced 30% after 9 kGy radiation. ► Radiation can be used as a pretreatment technology for azo dye-containing wastewater. ► Combining radiation with aerobic biological treatment is a feasible strategy.

  2. On numerical solution of Burgers' equation by homotopy analysis method

    International Nuclear Information System (INIS)

    Inc, Mustafa

    2008-01-01

    In this Letter, we present the Homotopy Analysis Method (shortly HAM) for obtaining the numerical solution of the one-dimensional nonlinear Burgers' equation. The initial approximation can be freely chosen with possible unknown constants which can be determined by imposing the boundary and initial conditions. Convergence of the solution and effects for the method is discussed. The comparison of the HAM results with the Homotopy Perturbation Method (HPM) and the results of [E.N. Aksan, Appl. Math. Comput. 174 (2006) 884; S. Kutluay, A. Esen, Int. J. Comput. Math. 81 (2004) 1433; S. Abbasbandy, M.T. Darvishi, Appl. Math. Comput. 163 (2005) 1265] are made. The results reveal that HAM is very simple and effective. The HAM contains the auxiliary parameter h, which provides us with a simple way to adjust and control the convergence region of solution series. The numerical solutions are compared with the known analytical and some numerical solutions

  3. Degradation of 2,4,5-trichlorophenoxyacetic acid in aqueous solution by 60Co-γ irradiation

    International Nuclear Information System (INIS)

    Liu Yuanxia; Yu Yuan; Bao Huaying

    2010-01-01

    2,4,5-trichlorophenoxyacetic acid(2,4,5-T) is one kind of phenoxy-hydroxy-acid herbicides, also is one kind of Endocrine Disrupting Chemicals. The degradation of 2,4,5-T in aqueous solution by 60 Co-γ irradiation was investigated in the paper. The degradation effect of different influencing factors, such as absorbed dose and irradiation aura, was studied respectively. The degradation products were preliminarily analyzed by High Performance Liquid Chromatography, UV-Vis spectrophotometer and Ion Chromatography. The results showed that 2,4,5-T could be effectively degraded in aqueous solutions by 60 Co-γ irradiation. Meanwhile, the Chloride ion was detected in the solution, whose concentration increased with the growth of absorbed dose. It was found that although both e-aq and ·OH originated from water radiolysis could eliminate 2,4,5-T, the dechlorination effect and the degradation products were different. (authors)

  4. A new solution method for wheel/rail rolling contact.

    Science.gov (United States)

    Yang, Jian; Song, Hua; Fu, Lihua; Wang, Meng; Li, Wei

    2016-01-01

    To solve the problem of wheel/rail rolling contact of nonlinear steady-state curving, a three-dimensional transient finite element (FE) model is developed by the explicit software ANSYS/LS-DYNA. To improve the solving speed and efficiency, an explicit-explicit order solution method is put forward based on analysis of the features of implicit and explicit algorithm. The solution method was first applied to calculate the pre-loading of wheel/rail rolling contact with explicit algorithm, and then the results became the initial conditions in solving the dynamic process of wheel/rail rolling contact with explicit algorithm as well. Simultaneously, the common implicit-explicit order solution method is used to solve the FE model. Results show that the explicit-explicit order solution method has faster operation speed and higher efficiency than the implicit-explicit order solution method while the solution accuracy is almost the same. Hence, the explicit-explicit order solution method is more suitable for the wheel/rail rolling contact model with large scale and high nonlinearity.

  5. A method for polymerizing insaturated monomers through irradiation in the presence of a salt

    International Nuclear Information System (INIS)

    Phalangas, C.J.; Restaino, A.J.; Yun, Hanbo.

    1975-01-01

    The method consists in irradiating an aqueous solution with a pH between about 2 and 12, comprising from 10 to 40% about an ethylene-insaturated monomer or of mixtures thereof with vinyl-sulfonic acid, an alkaline metal salt of said acid or acrylamide diacetone and at least 3% of a potassium, sodium, lithium, ammonium or aluminium salt, by means of highly powerful radiations, e.g. gamma rays, the radiation intensity being between 1000 and 200000 rads per hour and the overall radiation dose being in the 1000-30000 rads. The obtained product is a polymer aqueous solution either in the liquid state or in the form of a gel [fr

  6. An evaluation of solutions to moment method of biochemical oxygen ...

    African Journals Online (AJOL)

    This paper evaluated selected solutions of moment method in respect to Biochemical Oxygen Demand (BOD) kinetics with the aim of ascertain error free solution. Domestic - institutional wastewaters were collected two - weekly for three months from waste - stabilization ponds in Obafemi Awolowo University, Ile - Ife.

  7. Defining collaborative business rules management solutions : framework and method

    NARCIS (Netherlands)

    dr. Martijn Zoet; Johan Versendaal

    2014-01-01

    From the publishers' website: The goal of this research is to define a method for configuring a collaborative business rules management solution from a value proposition perspective. In an earlier published study (Business rules management solutions: added value by means of business

  8. STABILITY OF DOW CORNING Q2-3183A ANTIFOAM IN IRRADIATED HYDROXIDE SOLUTION

    International Nuclear Information System (INIS)

    White, T.; Crawford, C.; Burket, P.; Calloway, B.

    2009-01-01

    Researchers at the Savannah River National Laboratory (SRNL) examined the stability of Dow Corning Q2-3183A antifoam to radiation and aqueous hydroxide solutions. Initial foam control studies with Hanford tank waste showed the antifoam reduced foaming. The antifoam was further tested using simulated Hanford tank waste spiked with antifoam that was heated and irradiated (2.1 x 10 4 rad/h) at conditions (90 C, 3 M NaOH, 8 h) expected in the processing of radioactive waste through the Waste Treatment and Immobilization Plant (WTP) at Hanford. After irradiation, the concentration of the major polymer components polydimethylsiloxane (PDMS) and polypropylene glycol (PPG) in the antifoam was determined by gel permeation chromatography (GPC). No loss of the major polymer components was observed after 24 h and only 15 wt% loss of PDMS was reported after 48 h. The presence of degradation products were not observed by gas chromatography (GC), gas chromatography mass spectrometry (GCMS) or high performance liquid chromatography mass spectrometry (HPLC-MS). G values were calculated from the GPC analysis and tabulated. The findings indicate the antifoam is stable for 24 h after exposure to gamma radiation, heat, and alkaline simulated waste

  9. Effects of solute elements on irradiation hardening and microstructural evolution in low alloy steels

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Katsuhiko, E-mail: fujiik@inss.co.jp [Institute of Nuclear Safety System Inc., 64 Sata, Mihama 919-1205 (Japan); Ohkubo, Tadakatsu, E-mail: OHKUBO.Tadakatsu@nims.go.jp [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan); Fukuya, Koji, E-mail: fukuya@inss.co.jp [Institute of Nuclear Safety System Inc., 64 Sata, Mihama 919-1205 (Japan)

    2011-10-01

    The effects of the elements Mn, Ni, Si and Cu on irradiation hardening and microstructural evolution in low alloy steels were investigated in ion irradiation experiments using five kinds of alloys prepared by removing Mn, Ni and Si from, and adding 0.05 wt.%Cu to, the base alloy (Fe-1.5Mn-0.5Ni-0.25Si). The alloy without Mn showed less hardening and the alloys without Ni or Si showed more hardening. The addition of Cu had hardly any influence on hardening. These facts indicated that Mn enhanced hardening and that Ni and Si had some synergetic effects. The formation of solute clusters was not confirmed by atom probe (AP) analysis, whereas small dislocation loops were identified by TEM observation. The difference in hardening between the alloys with and without Mn was qualitatively consistent with loop formation. However, microstructural components that were not detected by the AP and TEM were assumed to explain the hardening level quantitatively.

  10. Design and Construction of Experiment for Direct Electron Irradiation of Uranyl Sulfate Solution: Bubble Formation and Thermal Hydraulics Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, Vakho [Argonne National Lab. (ANL), Argonne, IL (United States); Heltemes, Thad [Argonne National Lab. (ANL), Argonne, IL (United States); Sun, Zaijing [Argonne National Lab. (ANL), Argonne, IL (United States); Wardle, Kent E. [Argonne National Lab. (ANL), Argonne, IL (United States); Bailey, James [Argonne National Lab. (ANL), Argonne, IL (United States); Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States); Stepinski, Dominique [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-10-01

    Argonne is assisting SHINE Medical Technologies in developing SHINE, a system for producing fission-product 99Mo using a D/T-accelerator to produce fission in a non-critical target solution of aqueous uranyl sulfate. We have developed an experimental setup for studying thermal-hydraulics and bubble formation in the uranyl sulfate solution to simulate conditions expected in the SHINE target solution during irradiation. A direct electron beam from the linac accelerator will be used to irradiate a 20 L solution (sector of the solution vessel). Because the solution will undergo radiolytic decomposition, we will be able to study bubble formation and dynamics and effects of convection and temperature on bubble behavior. These experiments will serve as a verification/ validation tool for the thermal-hydraulic model. Utilization of the direct electron beam for irradiation allows homogeneous heating of a large solution volume and simplifies observation of the bubble dynamics simultaneously with thermal-hydraulic data collection, which will complement data collected during operation of the miniSHINE experiment. Irradiation will be conducted using a 30-40 MeV electron beam from the high-power linac accelerator. The total electron-beam power will be 20 kW, which will yield a power density on the order of 1 kW/L. The solution volume will be cooled on the front and back surfaces and central tube to mimic the geometry of the proposed SHINE solution vessel. Also, multiple thermocouples will be inserted into the solution vessel to map thermal profiles. The experimental design is now complete, and installation and testing are in progress.

  11. Development of detection methods for irradiated foods; development of immunological identification of irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyong Ae; Lee, Yoon Jin; Choi, Yoon Jung; Han, Su Kyong [Soonchunhyang University, Asan (Korea)

    2002-04-01

    Enzyme-linked Immunosorbent assay systems for the identification of irradiated egg, pork and chicken was developed. Eggs were irradiated in their shells to 0.5{approx}7kGy. Pork was irradiated to 0.5{approx}3kGy and chicken irradiated to 0.5kGy{approx}5kGy. The most sensitive proteins to irradiation were screened by SDS-PAGE and purified. Ovalbumin from egg, salt soluble protein(p) from pork, and salt soluble protein(c) from chicken showed the most sensitivity to irradiation. To investigate for a practical use in identifying of irradiated egg, pork and chicken, competitive ELISA was performed. The binding activity of ovalbumin to anti-ovalbumin IgG was reduced in a dose-dependent manner by irradiating up to 7kGy, and considerably lowered after irradiating at 7kGy. The concentration of 50% inhibition of ovalbumin to IgG was increased to 1.5(0.5kGy){approx}3.7(7kGy) times in an dose-dependent relationship. The binding activity of salt soluble protein(p) to anti-salt soluble protein IgG (anti-SSPp IgG)was also reduced in a dose-dependent manner by irradiating up to 3kGy, and considerably lowered after irradiating at 3kGy. The concentration of 50% inhibition of salt soluble protein to IgG was increased to 1.1(0.5kGy){approx}5.2(3kGy) times in a dose-dependent relationship. On the other hand, the binding activity of salt soluble protein(c) to anti-salt soluble protein IgG(anti-SSPc IgG) was reduced in a dose-dependent manner by irradiating up to 5kGy, too, and considerably lowered after irradiating at 5kGy. The concentration of 50% inhibition of salt soluble protein to IgG was increased to 1.1{approx}2.3 times in a dose-dependent relationship. SDS-PAGE of the irradiation sensitive proteins showed the partial breakdown of it was induced by irradiation. So, the lowering of binding activity was probably due to the partial breakdown of ovalbumin by irradiation. 25 refs., 12 figs., 5 tabs. (Author)

  12. Studies on rate equations for defects in irradiated solids using the local analysis method

    International Nuclear Information System (INIS)

    Carvalho e Camargo, M.U. de.

    1983-10-01

    The void formation and swelling phenomenon in material for nuclear reactors structures, mainly for fast reactors, has been studied by several authors. A simple calculation covering the basic instance of radiation damage in irradiated solid solution, using the local analysis in rate theory is presented here. A simple description of pratical and fundamental interest for the complex problem of solid solution under irradiation is given. (Author) [pt

  13. Methods for chemical recovery of non-carrier-added radioactive tin from irradiated intermetallic Ti-Sb targets

    Science.gov (United States)

    Lapshina, Elena V [Troitsk, RU; Zhuikov, Boris L [Troitsk, RU; Srivastava, Suresh C [Setauket, NY; Ermolaev, Stanislav V [Obninsk, RU; Togaeva, Natalia R [Obninsk, RU

    2012-01-17

    The invention provides a method of chemical recovery of no-carrier-added radioactive tin (NCA radiotin) from intermetallide TiSb irradiated with accelerated charged particles. An irradiated sample of TiSb can be dissolved in acidic solutions. Antimony can be removed from the solution by extraction with dibutyl ether. Titanium in the form of peroxide can be separated from tin using chromatography on strong anion-exchange resin. In another embodiment NCA radiotin can be separated from iodide solution containing titanium by extraction with benzene, toluene or chloroform. NCA radiotin can be finally purified from the remaining antimony and other impurities using chromatography on silica gel. NCA tin-117m can be obtained from this process. NCA tin-117m can be used for labeling organic compounds and biological objects to be applied in medicine for imaging and therapy of various diseases.

  14. Identification of irradiated food additives by photostimulated luminescence (PSL) method

    International Nuclear Information System (INIS)

    Yun, Hye Jeong; Kwon, Joong Ho; KIm, Dong Ho; Hur, Jung Mu; Yang, Suh Yung; Lee, Byoung Hun

    2008-01-01

    Photostimulated luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) analyses were conducted to detect whether 258 kinds of extracted and powdered forms food additives were irradiated or not. In a view of the PSL results, 9 kinds of the extracted and powdered samples (3.2%) showed over 5,000 photon counts (60 sec) -1 and these samples were judged to be irradiation-positive. Thirty nine kinds of the samples (15.6%) yielded 700-5,000 photon counts (60 sec) -1 and these samples were grouped into irradiation-potential, while the samples showed below 700 photon counts (60 sec) -1 sec were judged to be irradiation-negative. TL glow curves for minerals separated from 5 samples were detected at 150 degrees C with high intensity. However, TL analysis did not apply to other irradiation-positive and irradiation-potential samples because the minerals for TL detection were not separated from the samples. ESR measurements for irradiation-positive and irradiation-potential samples, judged by PSL detection, showed no specific signals to irradiation. The results indicated that PSL could be applied to identify irradiation treatment of extracted and powdered food additives, while TL was optional and ESR was not suitable for detection extracted and powdered food additives

  15. Development of detection methods for irradiated foods - Development of detection method for radiolytic products of irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyong Su; Lee, Eun Ryong; Hong, Hae Jung [Chosun University, Kwangju (Korea)

    2000-07-01

    Meats, nuts, legumes and cereals were irradiated with {sup 60}Co {gamma}-ray. The detection methods included the fat extraction from samples, isolation of hydrocarbons and 2-alkylcyclobutanones by florisil column chromatography and analyses of GC-FID and GC/MS analyzers. Concentrations of hydrocarbons and 2-clobutanones increased with the irradiation dose in meat, nuts, legumes and cereals. In nuts (sesame seeds, black sesame seeds, perilla seeds, pine nuts and peanuts), legumes (white beans, black soybeans, yellow bean sprout soybeans, mouse-eyed soybeans, mung beans, kidney beans and small red beans) and cereals (brown rice, corns and wheat), 8-heptadecene and 1,7-hexadecadiene originated from oleic acid and 6,9-heptadecadiene and 1,7,10-hexadecatriene induced from linoleic acids were the major hydrocarbons due to the composition of fatty acids. Concentrations of radiation-induced hydrocarbons in nuts were slightly reduced and hydrocarbons were still significantly detectable, during 6 months at -18 deg. C. In meats and nuts, 2-(5'-tetradecenyl)cyclobutanone formed from oleic acid was found in most. 2-Dodecylcyclobutanone was detected in a large amount. The concentrations of radiation-induced 2-alkylcyclobutanones in meats slightly decreased, but relatively constant during 6 months at -18 deg. C. 62 refs., 45 figs., 25 tabs. (Author)

  16. The recovery of 99Mo from solutions of irradiated Uranium using a column with nanoparticles of Titanium Dioxide

    International Nuclear Information System (INIS)

    Androne, G. E.; Petre, M.; Lazar, C. G.

    2016-01-01

    Molyibdenum-99 (T½ = 66.02 h) decays by beta emission to 99 Tcm (T½ = 6.02 h). The latter nuclide is used in many nuclear medicine applications. The 99 Mo is produced from irradiated high (HEU) or low (LEU) enriched uranium. In this work a sensitive and selective method for recovering Mo from uranium solution, using a column with titanium dioxide nanoparticles, is developed. The titanium dioxide (TiO 2 ) nanoparticles were synthesized via sol-gel method using titanium tetra-chloride as starting material and urea as a reacting medium. A 40 ml uranium solution containing 450 g/L uranyl nitrate, 1 M HNO 3 , and 4 mg Mo was loaded on a column containing 6 g of TiO 2 sorbent at 75°C. After loading, the column was washed with 1 M HNO 3 and H 2 O. Mo was stripped from the column with 0.1 M NaOH at 25°C. The ICP-MS results indicate that 80-95% of the initial mass of Mo was loaded on the column, and 90-94% of this quantity was recovered in the strip fraction. (authors)

  17. Simultaneous determination of uranium and plutonium in dissolver solution of irradiated fuel, using ID-TIMS. IRP-11

    International Nuclear Information System (INIS)

    Shah, Raju; Sasi Bhushan, K.; Govindan, R.; Alamelu, D.; Khodade, P.S.; Aggarwal, S.K.

    2007-01-01

    A simple sample preparation and simultaneous analysis method to determine uranium and plutonium from dissolver solution, employing the technique of Isotope Dilution Mass spectrometry has been demonstrated. The method used, co-elusion of Uranium and Plutonium from anion exchanger column after initial elution of major part of uranium in 1:5 HNO 3 in order to reduce the initial U/Pu ratio from 1000 to about 100-200 in the co-eluted fraction. Due to the availability of variable multi-collector system, different Faraday cups were adjusted to collect the different ion intensities corresponding to the different masses, during the simultaneous analysis of Uranium and Plutonium, loaded on Re double filament assembly. 233 U and PR grade Plutonium were used as spikes to determine Uranium and Plutonium from dissolver solution of irradiated fuel from research reactor. The possibility of getting the isotopic composition of uranium from the simultaneous analysis of co-eluted purified fraction of U and Pu from spiked aliquots is also explained. (author)

  18. New numerical method for solving the solute transport equation

    International Nuclear Information System (INIS)

    Ross, B.; Koplik, C.M.

    1978-01-01

    The solute transport equation can be solved numerically by approximating the water flow field by a network of stream tubes and using a Green's function solution within each stream tube. Compared to previous methods, this approach permits greater computational efficiency and easier representation of small discontinuities, and the results are easier to interpret physically. The method has been used to study hypothetical sites for disposal of high-level radioactive waste

  19. Method for Cs-137 separation from the decontamination solutions

    International Nuclear Information System (INIS)

    Toropov, I.G.; Efremenkov, V.M.; Toropova, V.V.; Satsukevich, V.M.; Davidov, Yu.P.

    1995-01-01

    In this work results of investigations are presented on separation of radiocaesium from the decontamination solutions containing reducing agents (thiocarbamide). The scientific basis for radiocaesium removal from the solution focuses on the state of the radionuclide and its sorption behavior in the solution with a complicated composition. Then using a combination of sorption and ultrafiltration methods it would be possible to concentrate the radionuclide in a small volume and to purify the main part of the solution. As a sorbent for radiocaesium removal from the solution, a ferrocyanide based sorbent is proposed. Use of this sorbent is justified since its high selectivity and effectiveness for radiocaesium sorption from the solutions of different composition is well known. When synthesis of the sorbent is performed directly in the treating solution, two components as a minimum should be added to it, namely K 4 Fe(CN) 6 and metal ions of Ni-II, Co-II, Cu-II, etc. The results are presented which show the possibility of radiocaesium separation from the decontamination solutions (containing 60--100 g/l of salts) using sorption and membrane separation methods without the use of metal salts. At the same time by using FE-2 in solution in the presence of cyanide ions and thiocarbamide, it is possible to avoid the addition of metal salts (Ni, Cu, etc.). Utilization of the proposed method for spent decontamination solution treatment allows a relatively easy way to reduce the concentration of radiocaesium in solution on 2--4 orders of magnitudes, and to exclude the utilization of relatively expensive metal salts

  20. On the modeling of irradiation-induced homogeneous precipitation in proton-bombarded Ni-Si solid solutions

    Science.gov (United States)

    Lam, Nghi Q.; Janghorban, K.; Ardell, A. J.

    1981-10-01

    Irradiation-induced solute redistribution leading to precipitation of coherent γ' particles in undersaturated Ni-based solid solutions containing 6 and 8 at.% Si during 400-keV proton bombardment was modeled, based on the concept of solute segregation in concentrated alloys under spatially-dependent defect production conditions. The combined effects of (i) an extremely large difference between the defect production rates in the peak-damage and mid-range regions during irradiation and (ii) a preferential coupling between the interstitial and solute fluxes generate a net transient flux of Si atoms into the mid-range region, which is much larger than the solute flux out of this location. As a result, the Si concentration exceeds the solubility limit and homogeneous precipitation of the γ' phase occurs in this particular region of the irradiated samples. The spatial, compositional and temperature dependences of irradiation-induced homogeneous precipitation derived from the present theoretical calculations are in good qualitative agreement with experimental observations

  1. Exact solution of some linear matrix equations using algebraic methods

    Science.gov (United States)

    Djaferis, T. E.; Mitter, S. K.

    1977-01-01

    A study is done of solution methods for Linear Matrix Equations including Lyapunov's equation, using methods of modern algebra. The emphasis is on the use of finite algebraic procedures which are easily implemented on a digital computer and which lead to an explicit solution to the problem. The action f sub BA is introduced a Basic Lemma is proven. The equation PA + BP = -C as well as the Lyapunov equation are analyzed. Algorithms are given for the solution of the Lyapunov and comment is given on its arithmetic complexity. The equation P - A'PA = Q is studied and numerical examples are given.

  2. Rapid spectrographic method for determining microcomponents in solutions

    International Nuclear Information System (INIS)

    Karpenko, L.I.; Fadeeva, L.A.; Gordeeva, A.N.; Ermakova, N.V.

    1984-01-01

    Rapid spectrographic method foe determining microcomponents (Cd, V, Mo, Ni, rare earths and other elements) in industrial and natural solutions has been developed. The analyses were conducted in argon medium and in the air. Calibration charts for determining individual rare earths in solutions are presented. The accuracy of analysis (Sr) was detection limit was 10 -3 -10 -4 mg/ml, that for rare earths - 1.10 -2 mg/ml. The developed method enables to rapidly analyze solutions (sewages and industrialllwaters, wine products) for 20 elements including 6 rare earths, using strandard equipment

  3. A method for the quantitative determination of uranium-233 in an irradiated thorium rod; Une methode de dosage de l'uranium 233 contenu dans un barreau de thorium irradie

    Energy Technology Data Exchange (ETDEWEB)

    Bathellier, A; Sontag, R; Chesne, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1961-07-01

    A rapid method for the quantitative determination of uranium-233 in irradiated thorium is described. A 30 per cent solution of trilaurylamine in xylene is used to extract the uranium from an aqueous hydrochloric acid solution and separate it from the thorium. This may be followed by {alpha} counting or fluorimetry. The practical operating conditions of the separation are discussed in detail. (author) [French] Une methode rapide de dosage de l'uranium-233 contenu dans le thorium irradie est decrite. Elle utilise la trilauryfamine a 30 pour cent dans le xylene pour extraire l'uranium d'une dissolution aqueuse chlorhydrique et le separer du thorium. Le comptage {alpha} ou la fluorimetrie sont alors possibles. Les conditions operatoires de la separation sont discutees et precisees. (auteur)

  4. An investigation of calibration methods for solution calorimetry.

    Science.gov (United States)

    Yff, Barbara T S; Royall, Paul G; Brown, Marc B; Martin, Gary P

    2004-01-28

    Solution calorimetry has been used in a number of varying applications within pharmaceutical research as a technique for the physical characterisation of pharmaceutical materials, such as quantifying small degrees of amorphous content, identifying polymorphs and investigating interactions between drugs and carbohydrates or proteins and carbohydrates. A calibration test procedure is necessary to validate the instrumentation; a few of the suggested calibration reactions are the enthalpies of solution associated with dissolving Tris in 0.1 M HCl or NaCl, KCl or propan-1-ol in water. In addition, there are a number of different methods available to determine enthalpies of solution from the experimental data provided by the calorimeter, for example, the Regnault-Pfaundler's method, a graphical extrapolation based on the Dickinson method, or a manual integration-based method. Thus, the aim of the study was to investigate how each of these methods influences the values for the enthalpy of solution. Experiments were performed according to the method outlined by Hogan and Buckton [Int. J. Pharm. 207 (2000) 57] using KCl (samples of 50, 100 and 200 mg), Tris and sucrose as calibrants. For all three materials the manual integration method was found to be the most consistent with the KCl in water (sample mass of 200 mg) being the most precise. Thus, this method is recommended for the validation of solution calorimeters.

  5. 4. German conference on food irradiation. Assessment - methods - detection

    International Nuclear Information System (INIS)

    Brockmann, A.; Erning, D.; Helle, N.; Schreiber, G.A.

    1994-01-01

    The fourth German Conference on Food Irradiation was held from 6th through 7th April 1994. Some seventy participants from the industry, scientific research, consumer organizations and supervising authorities discussed the pros and cons of the procedure and updated themselves on the latest governmental regulations, irradiation techniques, possibilities of detecting irradiated food and the results of official supervisory measures. The papers read at the meeting are summarized in this volume. (orig./vhe) [de

  6. Study on determination method of identifying irradiated chicken

    International Nuclear Information System (INIS)

    Guo Liping; Yu Xuejun; Yu Menghong; Fu Junjie; Zhang Shimin; Bao Jinsong

    2003-01-01

    The effects of gamma irradiation on the activities of aleipsis, peroxidase, perhydrol catalase and the peroxide values in chicken oil and effects of different storage time on self-oxidation of fat and lipa in irradiated chicken were studied. The results showed that the activities of aleipsis and perhydrol catalase in irradiated chicken decreased with increasing doses, and the peroxide activity and peroxide value of lipa increased with increase of doses. No significant effect of storage time on peroxide value was observed in the irradiated chicken

  7. Newton-like methods for Navier-Stokes solution

    Science.gov (United States)

    Qin, N.; Xu, X.; Richards, B. E.

    1992-12-01

    The paper reports on Newton-like methods called SFDN-alpha-GMRES and SQN-alpha-GMRES methods that have been devised and proven as powerful schemes for large nonlinear problems typical of viscous compressible Navier-Stokes solutions. They can be applied using a partially converged solution from a conventional explicit or approximate implicit method. Developments have included the efficient parallelization of the schemes on a distributed memory parallel computer. The methods are illustrated using a RISC workstation and a transputer parallel system respectively to solve a hypersonic vortical flow.

  8. Properties and solution methods for large location-allocation problems

    DEFF Research Database (Denmark)

    Juel, Henrik; Love, Robert F.

    1982-01-01

    Location-allocation with l$ _p$ distances is studied. It is shown that this structure can be expressed as a concave minimization programming problem. Since concave minimization algorithms are not yet well developed, five solution methods are developed which utilize the special properties of the l......Location-allocation with l$ _p$ distances is studied. It is shown that this structure can be expressed as a concave minimization programming problem. Since concave minimization algorithms are not yet well developed, five solution methods are developed which utilize the special properties...... of the location-allocation problem. Using the rectilinear distance measure, two of these algorithms achieved optimal solutions in all 102 test problems for which solutions were known. The algorithms can be applied to much larger problems than any existing exact methods....

  9. Quantitative detection of absorbed dose of irradiated dried fruit by ESR spectroscopy method

    International Nuclear Information System (INIS)

    Li Weiming; Ha Yiming; Zhao Yongfu; Zhang Yanli

    2011-01-01

    Sunflower seeds, walnuts, pistachios, and hazelnuts were used as experimental materials which were irradiated at 1.0, 3.0, 5.0 and 10.0 kGy, respectively. The relationships and correlations between ESR signal intensity and irradiation dosages were studied. The results showed that ESR spectra of irradiated samples were obviously different from that of CK, and the ESR signal intensity was positively related with the irradiation dose. After irradiation, the ESR intensity and spectrum shapes all changed and all four samples were clearly identified irradiated or unirradiated. The appearances of the two weak satellite lines which situated left and right to the intense singlet line in walnuts and pistachios proved the existence of cellulose radical. The detection dose limit of irradiated walnut was 1 kGy, and the detection limits of the other three samples were lower than 1 kGy. In conclusion, the ESR method could be used to irradiated. (authors)

  10. The photodegradation of trichloroethylene with or without the NAPL by UV irradiation in surfactant solutions

    International Nuclear Information System (INIS)

    Jia Juncai; Chu, W.

    2009-01-01

    The photodegradation of trichloroethene (TCE) with or without nonaqueous phase liquids (NAPL) by ultraviolet irradiation in surfactant solutions was examined in this study. The photodecay of TCE was studied at monochromatic 254 nm UV lamps. The effects of the type of surfactants, initial surfactant concentrations, pH levels and NAPL concentrations were examined to explore the photodecay of TCE. All the photodegradation of TCE followed pseudo-first-order decay kinetics at various conditions. It was found that Brij 35 overdose and higher initial pH levels may retard or inhibit the photodecay of TCE, mainly due to protons, intermediate generation and change of surfactant structure in the processes. The optimal condition for TCE photodecay was suggested based on the analysis of kinetics data, from which the reaction mechanism of TCE in the presence of NAPL form was also studied. In general, the reactions of TCE in micellar solution and NAPL pool can be considered as independent pathways due to the low molecule diffusion between the two phases

  11. The photodegradation of trichloroethylene with or without the NAPL by UV irradiation in surfactant solutions

    Energy Technology Data Exchange (ETDEWEB)

    Jia Juncai [Department of Civil and Structural Engineering, Research Centre for Urban Environmental Technology and Management, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Chu, W. [Department of Civil and Structural Engineering, Research Centre for Urban Environmental Technology and Management, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)], E-mail: cewchu@polyu.edu.hk

    2009-01-15

    The photodegradation of trichloroethene (TCE) with or without nonaqueous phase liquids (NAPL) by ultraviolet irradiation in surfactant solutions was examined in this study. The photodecay of TCE was studied at monochromatic 254 nm UV lamps. The effects of the type of surfactants, initial surfactant concentrations, pH levels and NAPL concentrations were examined to explore the photodecay of TCE. All the photodegradation of TCE followed pseudo-first-order decay kinetics at various conditions. It was found that Brij 35 overdose and higher initial pH levels may retard or inhibit the photodecay of TCE, mainly due to protons, intermediate generation and change of surfactant structure in the processes. The optimal condition for TCE photodecay was suggested based on the analysis of kinetics data, from which the reaction mechanism of TCE in the presence of NAPL form was also studied. In general, the reactions of TCE in micellar solution and NAPL pool can be considered as independent pathways due to the low molecule diffusion between the two phases.

  12. Identification of irradiation treatment in processed food. Pt. 2. Evaluation of a SPE-method for analyzing irradiation induced hydrocarbons

    International Nuclear Information System (INIS)

    Hartmann, M.; Ammon, J.; Berg, H.

    1996-01-01

    This paper deals with a solid phase extraction (SPE) method for the isolation of irradiation induced hydrocarbons which can replace the column chromatography described in the paragraph 35 LMBG (German Food Law) procedure L06.00-37. Using this new method, only a tenth of solvents and column material is necessary. The SPE method was a good as LC-LC-GC/FID or LC-LC-GC/MS in analyzing new or complex matrices like paprika or salmon. Additionally, it is fast, cheap and easy to perform. As far as we know, the detection of irradiation traetment in paprika powder by analyzing irradiation induced hydrocarbons has not been described before. The new method is a good alternative for the commonly used thermoluminescence procedure. (orig.) [de

  13. The Texas Solution to the Nation's Disposal Needs for Irradiated Hardware - 13337

    International Nuclear Information System (INIS)

    Britten, Jay M.

    2013-01-01

    The closure of the disposal facility in Barnwell, South Carolina, to out-of-compact states in 2008 left commercial nuclear power plants without a disposal option for Class B and C irradiated hardware. In 2012, Waste Control Specialists LLC (WCS) opened a highly engineered facility specifically designed and built for the disposal of Class B and C waste. The WCS facility is the first Interstate Compact low-level radioactive waste disposal facility to be licensed and operated under the Low-level Waste Policy Act of 1980, as amended in 1985. Due to design requirements of a modern Low Level Radioactive Waste (LLRW) facility, traditional methods for disposal were not achievable at the WCS site. Earlier methods primarily utilized the As Low as Reasonably Achievable (ALARA) concept of distance to accomplish worker safety. The WCS method required the use of all three ALARA concepts of time, distance, and shielding to ensure the safe disposal of this highly hazardous waste stream. (authors)

  14. Solidification method for organic solution and processing method of aqueous solution

    International Nuclear Information System (INIS)

    Kamoshida, Mamoru; Fukazawa, Tetsuo; Yazawa, Noriko; Hasegawa, Toshihiko

    1998-01-01

    The relative dielectric constant of an organic solution containing polar ingredients is controlled to 13 or less to enable its solidification. The polarity of the organic solution can be evaluated quantitatively by using the relative dielectric constant. If the relative dielectric constant is high, it can be controlled by dilution using a non-polar organic solvent of low relative dielectric constant. With such procedures, solidification can be conducted by using an economical 12-hydroxy stearic acid, process of liquid wastes can be facilitated and the safety can be ensured. (T.M.)

  15. Solution of the Schroedinger equation by a spectral method

    International Nuclear Information System (INIS)

    Feit, M.D.; Fleck, J.A. Jr.; Steiger, A.

    1982-01-01

    A new computational method for determining the eigenvalues and eigenfunctions of the Schroedinger equation is described. Conventional methods for solving this problem rely on diagonalization of a Hamiltonian matrix or iterative numerical solutions of a time independent wave equation. The new method, in contrast, is based on the spectral properties of solutions to the time-dependent Schroedinger equation. The method requires the computation of a correlation function from a numerical solution psi(r, t). Fourier analysis of this correlation function reveals a set of resonant peaks that correspond to the stationary states of the system. Analysis of the location of these peaks reveals the eigenvalues with high accuracy. Additional Fourier transforms of psi(r, t) with respect to time generate the eigenfunctions. The effectiveness of the method is demonstrated for a one-dimensional asymmetric double well potential and for the two-dimensional Henon--Heiles potential

  16. Comparison of three methods for detection of herbal food supplement irradiation

    DEFF Research Database (Denmark)

    Leth, Torben; Hansen, Hanne; Boisen, Flemming

    2006-01-01

    A survey for irradiation of 106 herbal food supplements was carried out in Denmark in 2003. The results from three methods, two screening methods and a specific method, were compared: Direct epifluorescent filter technique/aerobic plate count (DEFT/APC), photostimulated luminescence (PSL) and the......A survey for irradiation of 106 herbal food supplements was carried out in Denmark in 2003. The results from three methods, two screening methods and a specific method, were compared: Direct epifluorescent filter technique/aerobic plate count (DEFT/APC), photostimulated luminescence (PSL......) and thermoluminescence (TL) standardised by Comite Europeen de Normalisation (CEN). Forty samples screened positive with the DEFT/APC method. However, the TL method could only confirm irradiation of 15 samples, 11 samples wholly irradiated and 4 samples with a minor irradiated ingredient. Thus, the DEFT/APC method gave...

  17. Study of the fibrinogen - fibrin transformation kinetics and modifications caused to this reaction by irradiation (X rays) of the fibrinogen solution

    International Nuclear Information System (INIS)

    Hollard, D.; Suscillon, M.; Marcille, G.; Rambaud, F.; Baloyan, M.

    1966-01-01

    The authors present a spectrophotometric method for studying the transformation fibrinogen - fibrin. This method has the advantage of drawing immediately in graph form the three, phases of this transformation: proteolysis or monomerization; polymerisation; clot stabilization. It is a simple, faithful and easily reproductive technic. Owing to this method, they studied modifications of this transformation due to irradiation of fibrinogen solution. Low doses (90 000 R/mn) prevent transverse polymerisation. To upper doses (180 000 R and more), the action of thrombin on fibrinogen does not give an organised clot but a lacteous and fragile gel. There is not here a coagulation in the physiological understanding. (author) [fr

  18. Comparison of /sup 32/P therapy and sequential hemibody irradiation (HBI) for bony metastases as methods of whole body irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, H.; Choi, K.; Sohn, C.; Yaes, R.; Rotman, M.

    1986-06-01

    We report a retrospective study of 15 patients with prostate carcinoma and diffuse bone metastases treated with sodium /sup 32/P for palliation of pain at Downstate Medical Center and Kings County Hospital from 1973 to 1978. The response rates, duration of response, and toxicities are compared with those of other series of patients treated with /sup 32/P and with sequential hemibody irradiation. The response rates and duration of response are similar with both modalities ranging from 58 to 95% with a duration of 3.3 to 6 months with /sup 32/P and from 75 to 86% with a median duration of 5.5 months with hemibody irradiation. There are significant differences in the patterns of response and in the toxicities of the two treatment methods. Both methods cause significant bone marrow depression. Acute radiation syndrome, radiation pneumonitis, and alopecia are seen with sequential hemibody irradiation and not with /sup 32/P, but their incidence can be reduced by careful treatment planning. Hemibody irradiation can provide pain relief within 24 to 48 h, while /sup 32/P may produce an initial exacerbation of pain. Lower hemibody irradiation alone is less toxic than either upper hemibody irradiation or /sup 32/P treatment.

  19. Strand breaks, base release and post-irradiation changes in DNA γ-irradiated in dilute O2-saturated aqueous solution

    International Nuclear Information System (INIS)

    Ward, J.F.; Kuo, I.

    1976-01-01

    Gamma irradiation of DNA in dilute O 2 -saturated aqueous solution releases free bases and damaged bases from the macromolecule. The yields of these products were measured after column chromatographic separation. For double stranded DNA the immediate yield of bases varies from G = 0.012 for cytosine to G = 0.033 for adenine. The yields of released bases increase with post-irradiation time (the majority of the increase occurs in the first 2 hrs.) to yields in the range of G = 0.07 +- 0.012. Yields of two released damaged thymine radiation products from γ-irradiated 3 H thymine labelled DNA also increased with post-irradiation time. Strand breaks were measured in γ-irradiated single stranded DNA the initial yield G = 0.02 was low but increased with time to G = 0.07. No direct correlation between strand-break production and release of low molecular weight products is possible. The findings are discussed in terms of damage to DNA in vivo and its enzymatic repair

  20. Hydrogen/deuterium substitution methods: understanding water structure in solution

    International Nuclear Information System (INIS)

    Soper, A.K.

    1993-01-01

    The hydrogen/deuterium substitution method has been used for different applications, such as the short range order between water molecules in a number of different environments (aqueous solutions of organic molecules), or to study the partial structure factors of water at high pressure and temperature. The absolute accuracy that can be obtained remains uncertain, but important qualitative information can be obtained on the local organization of water in aqueous solution. Some recent results with pure water, methanol and dimethyl sulphoxide (DMSO) solutions are presented. It is shown that the short range water structure is not greatly affected by most solutes except at high concentrations and when the solute species has its own distinctive interaction with water (such as a dissolved small ion). 3 figs., 14 refs

  1. Cost–benefit analysis method for building solutions

    International Nuclear Information System (INIS)

    Araújo, Catarina; Almeida, Manuela; Bragança, Luís; Barbosa, José Amarilio

    2016-01-01

    Highlights: • A new cost–benefit method was developed to compare building solutions. • The method considers energy performance, life cycle costs and investment willingness. • The graphical analysis helps stakeholders to easily compare building solutions. • The method was applied to a case study showing consistency and feasibility. - Abstract: The building sector is responsible for consuming approximately 40% of the final energy in Europe. However, more than 50% of this consumption can be reduced through energy-efficient measures. Our society is facing not only a severe and unprecedented environmental crisis but also an economic crisis of similar magnitude. In light of this, EU has developed legislation promoting the use of the Cost-Optimal (CO) method in order to improve building energy efficiency, in which selection criteria is based on life cycle costs. Nevertheless, studies show that the implementation of energy-efficient solutions is far from ideal. Therefore, it is very important to analyse the reasons for this gap between theory and implementation as well as improve selection methods. This study aims to develop a methodology based on a cost-effectiveness analysis, which can be seen as an improvement to the CO method as it considers the investment willingness of stakeholders in the selection process of energy-efficient solutions. The method uses a simple graphical display in which the stakeholders’ investment willingness is identified as the slope of a reference line, allowing easy selection between building solutions. This method will lead to the selection of more desired – from stakeholders’ point of view – and more energy-efficient solutions than those selected through the CO method.

  2. Studies on the influences of. gamma. -ray irradiation upon food additives, (8). Influences of. gamma. -ray irradiation on polyphosphates in aqueous solution and in 'kamaboko'

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, M; Ishio, S [Kyushu Univ., Fukuoka (Japan). Faculty of Agriculture

    1981-08-01

    The effect of ..gamma..-ray irradiation on polyphosphates in aqueous solution and in ''kamaboko'' was investigated to evaluate the rate of decomposition and to examine the safety of the decomposed products. Tripolyphosphate, pyrophosphate and o-phosphate in aqueous solution were very stable against ..gamma..-ray irradiation, respectively. Tripolyphosphate added to ''surimi'' (minced and washed flesh of Alaska Pollack) completely changed to o-phosphate during the period of processing ''kamaboko'', but pyrophosphate was retained. Pyrophosphate content in ''kamaboko'' decreased in proportion to the dose of ..gamma..-ray. Decreased pyrophosphate was presumed to change into such products as insolubles which can not be extracted with 6% per chloric acid solution. Both tripolyphosphate and pyrophosphate changed enzymatically to o-phosphate. The activity of exopolyphosphatase in ''surimi'' was still retained. Polyphosphates added to ''surimi'' changed completely to o-phosphate during the frozen storage of ''surimi'', therefore, the application of ..gamma..-ray irradiation on ''kamaboko'' was considered not to induce any injurious substances from polyphosphates.

  3. Evaluation of Acoustic Cavitation in Terephthalic Acid Solutions Containing Gold Nanoparticles by the Spectrofluorometry Method

    Directory of Open Access Journals (Sweden)

    Ameneh Sazgarnia

    2012-01-01

    Full Text Available Background. When a liquid is irradiated with high intensity and low-frequency ultrasound, acoustic cavitation occurs. The existence of particles in a liquid provides nucleation sites for cavitation bubbles and leads to a decrease in the ultrasonic intensity threshold needed for cavitation onset. Materials and Methods. The study was designed to measure hydroxyl radicals in terephthalic acid solutions containing gold nanoparticles in a near field of a 1 MHz sonotherapy probe. The effect of ultrasound irradiation parameters containing mode of sonication and ultrasound intensity in hydroxyl radicals production have been investigated by the spectrofluorometry method. Results. Recorded fluorescence signal in terephthalic acid solution containing gold nanoparticles was higher than the terephthalic acid solution without gold nanoparticles. Also, the results showed that any increase in intensity of the sonication would be associated with an increase in the fluorescence intensity. Conclusion. Acoustic cavitation in the presence of gold nanoparticles has been introduced as a way for improving therapeutic effects on the tumors in sonodynamic therapy. Also, the terephthalic acid dosimetry is suitable for detecting and quantifying free hydroxyl radicals as a criterion of cavitation production over a certain range of conditions in medical ultrasound fields.

  4. Nitric oxide production by visible light irradiation of aqueous solution of nitrosyl ruthenium complexes.

    Science.gov (United States)

    Sauaia, Marília Gama; de Lima, Renata Galvão; Tedesco, Antonio Claudio; da Silva, Roberto Santana

    2005-12-26

    [Ru(II)L(NH(3))(4)(pz)Ru(II)(bpy)(2)(NO)](PF(6))(5) (L is NH(3), py, or 4-acpy) was prepared with good yields in a straightforward way by mixing an equimolar ratio of cis-[Ru(NO(2))(bpy)(2)(NO)](PF(6))(2), sodium azide (NaN(3)), and trans-[RuL(NH(3))(4)(pz)] (PF(6))(2) in acetone. These binuclear compounds display nu(NO) at ca. 1945 cm(-)(1), indicating that the nitrosyl group exhibits a sufficiently high degree of nitrosonium ion (NO(+)). The electronic spectrum of the [Ru(II)L(NH(3))(4)(pz)Ru(II)(bpy)(2)(NO)](5+) complex in aqueous solution displays the bands in the ultraviolet and visible regions typical of intraligand and metal-to-ligand charge transfers, respectively. Cyclic voltammograms of the binuclear complexes in acetonitrile give evidence of three one-electron redox processes consisting of one oxidation due to the Ru(2+/3+) redox couple and two reductions concerning the nitrosyl ligand. Flash photolysis of the [Ru(II)L(NH(3))(4)(pz)Ru(II)(bpy)(2)(NO)](5+) complex is capable of releasing nitric oxide (NO) upon irradiation at 355 and 532 nm. NO production was detected and quantified by an amperometric technique with a selective electrode (NOmeter). The irradiation at 532 nm leads to NO release as a consequence of a photoinduced electron transfer. All species exhibit similar photochemical behavior, a feature that makes their study extremely important for their future application in the upgrade of photodynamic therapy in living organisms.

  5. The influence of P solutes on an irradiated α-Fe matrix

    International Nuclear Information System (INIS)

    Hurchand, H.; Kenny, S.D.; Sanz-Navarro, C.F.; Smith, R.; Flewitt, P.E.J.

    2005-01-01

    Atomistic simulations of collision cascades in a Fe-0.04at.%P matrix and a pure Fe matrix are compared to investigate the interaction of the phosphorus atoms with the radiation. The simulations were performed for a primary knock-on atom having an energy in the range 1-16 keV. It is observed that the P atom in the Fe matrix does not increase significantly the damage induced to the lattice post irradiation. The density of vacancies and the morphology of the clusters formed in the Fe-0.04at.%P system are indistinguishable from residual defects produced in a pure irradiated Fe matrix. There are two mechanisms by which the Fe interstitials interact with the P atoms. The first occurs when a P atom is dislodged from its substitutional position by a recoil atom and combines with an Fe interstitial to form a mixed dumbbell. The second is one in which the Fe interstitial is attracted to a substitutional P atom due to the lattice strain region in the vicinity of the P atom. In this case the P atom acts as an attractive centre for interstitial Fe atoms and stabilises them into Fe-P nano-clusters. Nearly 35% of the atoms which are ejected from the core region of the cascade during the ballistic phase form such solute-defect clusters which remain pinned over the period of several hundred picoseconds. Finally, the radiation induced mobility of the P atom is reported. Substitutional P atoms whether isolated or as part of the larger defect clusters have a high energy barrier for diffusion but the P atoms displaced from substitutional sites can diffuse through the lattice by hopping between dumbbell and tetrahedral sites

  6. Method for improving solution flow in solution mining of a mineral

    International Nuclear Information System (INIS)

    Moore, T.

    1980-01-01

    An improved method for the solution mining of a mineral from a subterranean formation containing same in which an injection and production well are drilled and completed within said formation, leach solution and an oxidant are injected through said injection well into said formation to dissolve said mineral, and said dissolved mineral is recovered via said production well, wherein the improvement comprises pretreating said formation with an acid gas to improve the permeabiltiy thereof

  7. The characterization methods for colloids in aqueous solutions

    International Nuclear Information System (INIS)

    Vuorinen, U.; Kumpulainen, H.

    1993-11-01

    This literature review deals with characterization methods for colloids in aqueous solutions and in groundwater. The basis for the review has been the needs of nuclear waste disposal studies and methods applicable in such studies. The methods considered include non-destructive laserspectroscopic methods (e.g. TRLFS, LPAS, PALS), several separation methods (e.g. ultrafiltration, dialysis, electrophoresis, field-flow-fractionation) and also some surface analytical methods, as well as some other methods giving additional information on formation and migration properties of colloids. (au.) (71 refs., 13 figs., 3 tabs.)

  8. Ineffectiveness of a fluorometric method for identifying irradiated food base on thymine glycol

    International Nuclear Information System (INIS)

    Ewing, D.D.; Stepanik, T.M.

    1992-01-01

    At dosages used for food irradiation, some of the thymine present in the DNA of irradiated food may be converted to thymine glycol. A fluorometric assay for thymine glycol was investigated as a possible method of detecting irradiated foods based on this effect. Experiments were performed on homogenates of irradiated chicken breast meat and on DNA isolated from irradiated chicken breast meat. In both cases the assay was subject to interference from one of the reagents, o-aminobenzaldehyde, and lacked the necessary sensitivity to detect the thymine glycol produced by radiolysis of the DNA at relevant dosages

  9. Differential and difference equations a comparison of methods of solution

    CERN Document Server

    Maximon, Leonard C

    2016-01-01

    This book, intended for researchers and graduate students in physics, applied mathematics and engineering, presents a detailed comparison of the important methods of solution for linear differential and difference equations - variation of constants, reduction of order, Laplace transforms and generating functions - bringing out the similarities as well as the significant differences in the respective analyses. Equations of arbitrary order are studied, followed by a detailed analysis for equations of first and second order. Equations with polynomial coefficients are considered and explicit solutions for equations with linear coefficients are given, showing significant differences in the functional form of solutions of differential equations from those of difference equations. An alternative method of solution involving transformation of both the dependent and independent variables is given for both differential and difference equations. A comprehensive, detailed treatment of Green’s functions and the associat...

  10. Particular solution of the discrete-ordinate method.

    Science.gov (United States)

    Qin, Yi; Box, Michael A; Jupp, David L

    2004-06-20

    We present two methods that can be used to derive the particular solution of the discrete-ordinate method (DOM) for an arbitrary source in a plane-parallel atmosphere, which allows us to solve the transfer equation 12-18% faster in the case of a single beam source and is even faster for the atmosphere thermal emission source. We also remove the divide by zero problem that occurs when a beam source coincides with a Gaussian quadrature point. In our implementation, solution for multiple sources can be obtained simultaneously. For each extra source, it costs only 1.3-3.6% CPU time required for a full solution. The GDOM code that we developed previously has been revised to integrate with the DOM. Therefore we are now able to compute the Green's function and DOM solutions simultaneously.

  11. Milestones in the Development of Iterative Solution Methods

    Czech Academy of Sciences Publication Activity Database

    Axelsson, Owe

    2010-01-01

    Roč. 2010, - (2010), s. 1-33 ISSN 2090-0147 Institutional research plan: CEZ:AV0Z30860518 Keywords : iterative solution methods * convergence acceleration methods * linear systems Subject RIV: JC - Computer Hardware ; Software http://www.hindawi.com/journals/jece/2010/972794.html

  12. Comparing numerical methods for the solutions of the Chen system

    International Nuclear Information System (INIS)

    Noorani, M.S.M.; Hashim, I.; Ahmad, R.; Bakar, S.A.; Ismail, E.S.; Zakaria, A.M.

    2007-01-01

    In this paper, the Adomian decomposition method (ADM) is applied to the Chen system which is a three-dimensional system of ODEs with quadratic nonlinearities. The ADM yields an analytical solution in terms of a rapidly convergent infinite power series with easily computable terms. Comparisons between the decomposition solutions and the classical fourth-order Runge-Kutta (RK4) numerical solutions are made. In particular we look at the accuracy of the ADM as the Chen system changes from a non-chaotic system to a chaotic one. To highlight some computational difficulties due to a high Lyapunov exponent, a comparison with the Lorenz system is given

  13. Solution Methods for the Periodic Petrol Station Replenishment Problem

    Directory of Open Access Journals (Sweden)

    C Triki

    2013-12-01

    Full Text Available In this paper we introduce the Periodic Petrol Station Replenishment Problem (PPSRP over a T-day planning horizon and describe four heuristic methods for its solution. Even though all the proposed heuristics belong to the common partitioning-then-routing paradigm, they differ in assigning the stations to each day of the horizon. The resulting daily routing problems are then solved exactly until achieving optimalization. Moreover, an improvement procedure is also developed with the aim of ensuring a better quality solution. Our heuristics are tested and compared in two real-life cases, and our computational results show encouraging improvements with respect to a human planning solution

  14. Food irradiation: physical-chemical, technological and economical background and competing methods of food preservation

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1994-01-01

    Physical, chemical and technical as well as economical background of food preservation by irradiation have been performed. The radiation sources and the elements of radiation chemistry connected with their use in food irradiation process have been shown. The problems of dosimetry and endurance of dose uniformity for processed products have been also discussed. The other methods of food preservation and their weakness and advantages have been also presented and compared with food irradiation method

  15. Spectral radiative property control method based on filling solution

    International Nuclear Information System (INIS)

    Jiao, Y.; Liu, L.H.; Hsu, P.-F.

    2014-01-01

    Controlling thermal radiation by tailoring spectral properties of microstructure is a promising method, can be applied in many industrial systems and have been widely researched recently. Among various property tailoring schemes, geometry design of microstructures is a commonly used method. However, the existing radiation property tailoring is limited by adjustability of processed microstructures. In other words, the spectral radiative properties of microscale structures are not possible to change after the gratings are fabricated. In this paper, we propose a method that adjusts the grating spectral properties by means of injecting filling solution, which could modify the thermal radiation in a fabricated microstructure. Therefore, this method overcomes the limitation mentioned above. Both mercury and water are adopted as the filling solution in this study. Aluminum and silver are selected as the grating materials to investigate the generality and limitation of this control method. The rigorous coupled-wave analysis is used to investigate the spectral radiative properties of these filling solution grating structures. A magnetic polaritons mechanism identification method is proposed based on LC circuit model principle. It is found that this control method could be used by different grating materials. Different filling solutions would enable the high absorption peak to move to longer or shorter wavelength band. The results show that the filling solution grating structures are promising for active control of spectral radiative properties. -- Highlights: • A filling solution grating structure is designed to adjust spectral radiative properties. • The mechanism of radiative property control is studied for engineering utilization. • Different grating materials are studied to find multi-functions for grating

  16. Generalized Truncated Methods for an Efficient Solution of Retrial Systems

    Directory of Open Access Journals (Sweden)

    Ma Jose Domenech-Benlloch

    2008-01-01

    Full Text Available We are concerned with the analytic solution of multiserver retrial queues including the impatience phenomenon. As there are not closed-form solutions to these systems, approximate methods are required. We propose two different generalized truncated methods to effectively solve this type of systems. The methods proposed are based on the homogenization of the state space beyond a given number of users in the retrial orbit. We compare the proposed methods with the most well-known methods appeared in the literature in a wide range of scenarios. We conclude that the proposed methods generally outperform previous proposals in terms of accuracy for the most common performance parameters used in retrial systems with a moderated growth in the computational cost.

  17. Amination of oxy acids in aqueous solution by gamma-irradiation

    International Nuclear Information System (INIS)

    Ema, Kimiko; Kato, Taizo; Shinagawa, Mutsuaki

    1978-01-01

    Alanin, β-alanine, glicine, and aspartic, α-amino-n-butyric, and γ-amino-n-butyric acids were obtained by γ-irradiation of aqueous ammonia solutions of lactic, β-oxypropionic, glycolic, malic, α-oxybutyric, and γ-oxybutyric acids, respectively. The yields of amino acids were examined for functions of radiation dose (0.75 - 3.55Mrad), concentrations of oxy acid (0.01 - 0.1M) and ammonia (0.1 - 15M), and substances added as radical (potassium iodide), and hydrated electron (nitrous oxide) scavengers. The maximum G-values were 0.6 for alanine in a solution of 0.1M lactic acid-4M ammonia and some nitrous oxide and 1.14 for β-alanine in a solution of 0.1M β-oxypropionic acid and 0.7M ammonia. The yield of alanine increased with increased concentrations of lactic acid and ammonia due to saturation of nitrous oxide but decreased when potassium iodide (0.03M) was added. The yield of β-alanine showed a maximum increase at ca. 0.7M ammonia and decreased when potassium iodide and nitrous oxide were added. Serine was obtained from G = 0.002 in a solution of β-oxypropionic acid and increased to G = 0.058 due to saturation of nitrous oxide. The manner of chemical amination due to radiation was studied from the above results. In general, oxy acids from which hydrogen has been abstracted by an H or OH radical react with ammonia to form amino acids. The effect of ammonia concentration on the yield of amino acids demonstrates that the NH 2 radical abstracts the α-hydrogen of lactic acid but does not react with the β-hydrogen of β-oxypropionic acid. The effect of nitrous oxide indicates that hydrated electrons interfere with alanine formation, contribute to β-alanine formation, react with the carboxyl group of lactic acids to form lactamide, and abstract the β-hydroxyl group of β-oxypropionic acids to form β-alanine. (Bell, E.)

  18. Milestones in the Development of Iterative Solution Methods

    Directory of Open Access Journals (Sweden)

    Owe Axelsson

    2010-01-01

    Full Text Available Iterative solution methods to solve linear systems of equations were originally formulated as basic iteration methods of defect-correction type, commonly referred to as Richardson's iteration method. These methods developed further into various versions of splitting methods, including the successive overrelaxation (SOR method. Later, immensely important developments included convergence acceleration methods, such as the Chebyshev and conjugate gradient iteration methods and preconditioning methods of various forms. A major strive has been to find methods with a total computational complexity of optimal order, that is, proportional to the degrees of freedom involved in the equation. Methods that have turned out to have been particularly important for the further developments of linear equation solvers are surveyed. Some of them are presented in greater detail.

  19. Experimental Results for Direct Electron Irradiation of a Uranyl Sulfate Solution: Bubble Formation and Thermal Hydraulics Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, Vakhtang [Argonne National Lab. (ANL), Argonne, IL (United States); Heltemes, Thad [Argonne National Lab. (ANL), Argonne, IL (United States); Sun, Zaijing [Argonne National Lab. (ANL), Argonne, IL (United States); Wardle, Kent E. [Argonne National Lab. (ANL), Argonne, IL (United States); Bailey, James [Argonne National Lab. (ANL), Argonne, IL (United States); Stepinski, Dominique [Argonne National Lab. (ANL), Argonne, IL (United States); Jerden, James [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-01-30

    In support of the development of accelerator-driven production of fission product Mo-99 as proposed by SHINE Medical Technologies, a 35 MeV electron linac was used to irradiate depleted-uranium (DU) uranyl sulfate dissolved in pH 1 sulfuric acid at average power densities of 6 kW, 12 kW, and 15 kW. During these irradiations, gas bubbles were generated in the solution due to the radiolytic decomposition of water molecules in the solution. Multiple video cameras were used to record the behavior of bubble generation and transport in the solution. Seven six-channel thermocouples were used to record temperature gradients in the solution from self-heating. Measurements of hydrogen and oxygen concentrations in a helium sweep gas were recorded by a gas chromatograph to estimate production rates during irradiation. These data are being used to validate a computational fluid dynamics (CFD) model of the experiment that includes multiphase flow and a custom bubble injection model for the solution region.

  20. Experimental Results for Direct Electron Irradiation of a Uranyl Sulfate Solution: Bubble Formation and Thermal Hydraulics Studies

    International Nuclear Information System (INIS)

    Chemerisov, Sergey; Gromov, R.; Makarashvili, Vakhtang; Heltemes, Thad; Sun, Zaijing; Wardle, Kent E.; Bailey, James; Stepinski, Dominique; Jerden, James; Vandegrift, George F.

    2015-01-01

    In support of the development of accelerator-driven production of fission product Mo-99 as proposed by SHINE Medical Technologies, a 35 MeV electron linac was used to irradiate depleted-uranium (DU) uranyl sulfate dissolved in pH 1 sulfuric acid at average power densities of 6 kW, 12 kW, and 15 kW. During these irradiations, gas bubbles were generated in the solution due to the radiolytic decomposition of water molecules in the solution. Multiple video cameras were used to record the behavior of bubble generation and transport in the solution. Seven six-channel thermocouples were used to record temperature gradients in the solution from self-heating. Measurements of hydrogen and oxygen concentrations in a helium sweep gas were recorded by a gas chromatograph to estimate production rates during irradiation. These data are being used to validate a computational fluid dynamics (CFD) model of the experiment that includes multiphase flow and a custom bubble injection model for the solution region.

  1. Valency stabilization of polyvalent ions during gamma irradiation of their aqueous solutions by sacrificial protection. I- Valency stabilization of Fe (II) ions by sulphate ions

    Energy Technology Data Exchange (ETDEWEB)

    Barakat, M F [Nuclear chemistry department, hot lab. center, Atomic Energy Authority, Cairo, (Egypt); Abdel-Hamid, M M [Arab Atomic Energy Agency, P.O. Box 402 El-Manzah-1004 Tunis, (Tunisia)

    1995-10-01

    Polyvalent ions are very sensitive to gamma irradiation in aqueous solutions. The present work is a part of a more comprehensive study dealing with the stabilization or protection of certain oxidation states of some polyvalent ions during their gamma irradiation in aqueous systems. The behaviour of aqueous acidic Fe (II) solutions during gamma irradiation, in presence the prevailing protection mechanism. The conditions and stabilization limits in the studied case has been found out. 9 figs.

  2. Valency stabilization of polyvalent ions during gamma irradiation of their aqueous solutions by sacrificial protection. I- Valency stabilization of Fe (II) ions by sulphate ions

    International Nuclear Information System (INIS)

    Barakat, M.F.; Abdel-Hamid, M.M.

    1995-01-01

    Polyvalent ions are very sensitive to gamma irradiation in aqueous solutions. The present work is a part of a more comprehensive study dealing with the stabilization or protection of certain oxidation states of some polyvalent ions during their gamma irradiation in aqueous systems. The behaviour of aqueous acidic Fe (II) solutions during gamma irradiation, in presence the prevailing protection mechanism. The conditions and stabilization limits in the studied case has been found out. 9 figs

  3. Effects of radical scavengers on aqueous solutions exposed to heavy-ion irradiation using the liquid microjet technique

    Science.gov (United States)

    Nomura, Shinji; Tsuchida, Hidetsugu; Furuya, Ryousuke; Miyahara, Kento; Majima, Takuya; Itoh, Akio

    2015-12-01

    The effects of the radical scavenger ascorbic acid on water radiolysis are studied by fast heavy-ion irradiation of aqueous solutions of ascorbic acid, using the liquid microjet technique under vacuum. To understand the reaction mechanisms of hydroxyl radicals in aqueous solutions, we directly measure secondary ions emitted from solutions with different ascorbic acid concentrations. The yield of hydronium secondary ions is strongly influenced by the reaction between ascorbic acid and hydroxyl radicals. From analysis using a simple model considering chemical equilibria, we determine that the upper concentration limit of ascorbic acid with a radical scavenger effect is approximately 70 μM.

  4. Effects of radical scavengers on aqueous solutions exposed to heavy-ion irradiation using the liquid microjet technique

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Shinji [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Tsuchida, Hidetsugu, E-mail: tsuchida@nucleng.kyoto-u.ac.jp [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Quantum Science and Engineering Center, Kyoto University, Uji 611-0011 (Japan); Furuya, Ryousuke; Miyahara, Kento [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Majima, Takuya; Itoh, Akio [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Quantum Science and Engineering Center, Kyoto University, Uji 611-0011 (Japan)

    2015-12-15

    The effects of the radical scavenger ascorbic acid on water radiolysis are studied by fast heavy-ion irradiation of aqueous solutions of ascorbic acid, using the liquid microjet technique under vacuum. To understand the reaction mechanisms of hydroxyl radicals in aqueous solutions, we directly measure secondary ions emitted from solutions with different ascorbic acid concentrations. The yield of hydronium secondary ions is strongly influenced by the reaction between ascorbic acid and hydroxyl radicals. From analysis using a simple model considering chemical equilibria, we determine that the upper concentration limit of ascorbic acid with a radical scavenger effect is approximately 70 μM.

  5. Effects of radical scavengers on aqueous solutions exposed to heavy-ion irradiation using the liquid microjet technique

    International Nuclear Information System (INIS)

    Nomura, Shinji; Tsuchida, Hidetsugu; Furuya, Ryousuke; Miyahara, Kento; Majima, Takuya; Itoh, Akio

    2015-01-01

    The effects of the radical scavenger ascorbic acid on water radiolysis are studied by fast heavy-ion irradiation of aqueous solutions of ascorbic acid, using the liquid microjet technique under vacuum. To understand the reaction mechanisms of hydroxyl radicals in aqueous solutions, we directly measure secondary ions emitted from solutions with different ascorbic acid concentrations. The yield of hydronium secondary ions is strongly influenced by the reaction between ascorbic acid and hydroxyl radicals. From analysis using a simple model considering chemical equilibria, we determine that the upper concentration limit of ascorbic acid with a radical scavenger effect is approximately 70 μM.

  6. Influence of physical and chemical parameters on the irradiation of aqueous solutions of phenol by electron beam

    International Nuclear Information System (INIS)

    Pellizzari, Fabien

    2005-01-01

    The aim of this work was the study of the influence of different parameters by electron beam irradiation on the decomposition of phenol in aqueous solution. A simulation based on a simplified mechanism emphasized the importance of the oxygenation of the solutions in the removal of phenol by ionisation. A model of the reactor used was proposed from the study of the influence of the beam energy on the decomposition of phenol. Penetration depths of the electrons were determined. Phenol degradation was found to increase with the dose rate. The fraction of the dose into several passages under the electron beam improved the abatement of the phenol. The reoxygenation of the solutions between each passage and the kinetic expressions of irradiation could explain this effect. As expected, the first by-products identified were originated from the reaction of phenol with hydroxyl radicals. [fr

  7. An EPR study of positive hole transfer and trapping in irradiated frozen solutions containing aromatic traps

    International Nuclear Information System (INIS)

    Egorov, A.V.; Zezin, A.A.; Feldman, V.I.

    2002-01-01

    Complete text of publication follows. Processes of positive hole migration and trapping are of basic significance for understanding of the primary events in the radiation chemistry of solid molecular systems. Specific interest is concerned with the case, when ionization energies of 'hole traps' are rather close, so one may expect 'fine tuning' effects resulting from variations in conformation, weak interactions, molecular packing, etc. In this contribution we report the results of EPR study of formation of radical cations in irradiated frozen halocarbon solutions containing aromatic molecules of different structure. Using the 'two-trap' model made it possible to obtain an evidence for efficient long-range trap-to-trap positive hole transfer between alkyl benzene molecules with close ionization energies distributed in the matrices with high ionization potentials. The distance of transfer was found to be 2-4 nm. In the case of frozen solutions containing ethylbenzene and toluene, it was found that the efficiency and direction of hole transfer was controlled by the conformation of ethylbenzene radical cation. The study of positive hole localization in 'bridged' diphenyls of Ph(CH 2 ) n Ph type revealed that the structure of radical cations of these species was affected by local environment (type of halocarbon matrix) and the conformational flexibility of 'bridge'. In summary, we may conclude that migration and localization of positive hole in rigid systems containing aromatic 'traps' is quite sensitive to rather subtle effects. This conclusion may be of common significance for the radiation chemistry of systems with physical dispersion of the traps of similar chemical structure (e.g. macromolecules, adsorbed molecules, etc.)

  8. Analytical methods for post-irradiation dosimetry of foods

    International Nuclear Information System (INIS)

    Rosenthal, I.

    1993-01-01

    The trade and acceptance of foods treated with ionizing radiation, gamma radiation or x-rays, require appropriate means of control. A foolproof test to detect whether or not food has been irradiated, and eventually to quantify the amount of radiation, is vital to verify the labelling and enforce legislation. Such an assay also provides the information for avoiding repeated irradiations which are likely to degrade the food in terms of organoleptic acceptability and nutritional quality. (author)

  9. Mutagenicity of γ-irradiated oxygenated and deoxygenated solutions of 2-deoxy-D-ribose and D-ribose in Salmonella typhimurium

    International Nuclear Information System (INIS)

    Wilmer, J.; Leveling, H.; Schubert, J.

    1981-01-01

    Solutions of 2-deoxy-D-ribose and D-ribose were γ-irradiated under different experimental conditions and tested for mutagenicity, with and without preincubation, in Salmonella typhimurium. The irradiated sugar solutions were mutagenic in the tester strains TA 100 and TA 98. Except for malonaldehyde (MDA), which is not mutagenic in the concentrations produced radiolytically, the relative mutagenicities of the individual radiolytic products are unknown. With irradiated solutions of 2-deoxy-D-ribose, a relationship was found between the level of non-MDA aldehydes and the mutagenicity in TA 100. Heating the irradiated solutions of 2-deoxy-D-ribose resulted in a temperature-dependent reduction fo the mutagenicity. Autoclaved, non-irradiated solutions of 2-deoxy-D-ribose were not mutagenic in the Salmonella test. (orig.)

  10. An Expedient Method for the Synthesis of Thiosemicarbazones under Microwave Irradiation in Solvent-free Medium

    Institute of Scientific and Technical Information of China (English)

    LI, Jian-Ping; ZHENG, Peng-Zhi; ZHU, Jun-Ge; LIU, Rui-Jie; QU, Gui-Rong

    2006-01-01

    A simple, efficient and eco-friendly method for the synthesis of thiosemicarbazones from thiosemicarbazides and aldehyde under microwave irradiation has been reported, and no solvent and catalyst were used. And the technique of microwave irradiation coupled with solvent-free condition proved to be a quite valuable method in the organic synthesis.

  11. Passive Methods as a Solution for Improving Indoor Environments

    CERN Document Server

    Orosa, José A

    2012-01-01

    There are many aspects to consider when evaluating or improving an indoor environment; thermal comfort, energy saving, preservation of materials, hygiene and health are all key aspects which can be improved by passive methods of environmental control. Passive Methods as a Solution for Improving Indoor Environments endeavours to fill the lack of analysis in this area by using over ten years of research to illustrate the effects of methods such as thermal inertia and permeable coverings; for example, the use of permeable coverings is a well known passive method, but its effects and ways to improve indoor environments have been rarely analyzed.   Passive Methods as a Solution for Improving Indoor Environments  includes both software simulations and laboratory and field studies. Through these, the main parameters that characterize the behavior of internal coverings are defined. Furthermore, a new procedure is explained in depth which can be used to identify the real expected effects of permeable coverings such ...

  12. Production of acetic acid from ethanol solution by acetobactor acetigenum and effect of gamma-ray irradiation on the bacteria

    International Nuclear Information System (INIS)

    Umar, J.M.; Matsuhashi, Shinpei; Hashimoto, Shoji.

    1996-03-01

    A preliminary study on fermentation of acetic acid by S. cerevisiae and A. acetigenum was carried out to obtain information to develop the effective utilization technology of agricultural liquid wastes. Aqueous solutions of glucose and/or ethanol were used as a model of agricultural liquid waste. The effect of gamma-ray irradiation on A. acetigenum for enhancement of the fermentation was also examined. In this study, irradiated A. acetigenum had activity to produce acetic acid even after loss the activity to grow. (author)

  13. Production of acetic from ethanol solution by acetobactor acetigenum and effect of gamma-ray irradiation on the bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Umar, J.M. [National Atomic Energy Agency, Jakarta (Indonesia). Center for Application of Isotopes and Radiation; Matsuhashi, Shinpei; Hashimoto, Shoji

    1996-03-01

    A preliminary study on fermentation of acetic acid by S. cerevisiae and A. acetigenum was carried out to obtain information to develop the effective utilization technology of agricultural liquid wastes. Aqueous solutions of glucose and/or ethanol were used as a model of agricultural liquid waste. The effect of gamma-ray irradiation on A. acetigenum for enhancement of the fermentation was also examined. In this study, irradiated A. acetigenum had activity to produce acetic acid even after loss the activity to grow. (author).

  14. Comparative analysis of solution methods of the punctual kinetic equations

    International Nuclear Information System (INIS)

    Hernandez S, A.

    2003-01-01

    The following one written it presents a comparative analysis among different analytical solutions for the punctual kinetics equation, which present two variables of interest: a) the temporary behavior of the neutronic population, and b) The temporary behavior of the different groups of precursors of delayed neutrons. The first solution is based on a method that solves the transfer function of the differential equation for the neutronic population, in which intends to obtain the different poles that give the stability of this transfer function. In this section it is demonstrated that the temporary variation of the reactivity of the system can be managed as it is required, since the integration time for this method doesn't affect the result. However, the second solution is based on an iterative method like that of Runge-Kutta or the Euler method where the algorithm was only used to solve first order differential equations giving this way solution to each differential equation that conforms the equations of punctual kinetics. In this section it is demonstrated that only it can obtain a correct temporary behavior of the neutronic population when it is integrated on an interval of very short time, forcing to the temporary variation of the reactivity to change very quick way without one has some control about the time. In both methods the same change is used so much in the reactivity of the system like in the integration times, giving validity to the results graph the one the temporary behavior of the neutronic population vs. time. (Author)

  15. Effectiveness of Ultrasound and Ultraviolet Irradiation onDegradation of Carbaryl from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    M Khoobdel

    2010-06-01

    Full Text Available Background: Carbaryl (1-naphthyl-N-methyl carbamate is a chemical in the carbamate family used chiefly as an insecticide. It is a cholinesterase inhibitor and is toxic to humans and classified as a likely human carcinogen. In the present study, the degradation of the carbaryl pesticide was investigated in the laboratory synthetic samples of tap water, in the effect of sonolysis and photolysis processes.Methods: This study was conducted during 2006-7 in Chemistry and Biochemistry of Pesticides Laboratory in Tehran University of Medical Sciences (TUMS in Iran. The carbaryl (80% was used for preparing samples. First concentration of all samples were 4 mg/l. Sonochemical examinations in ultrasound reactor was done in two 35, 130 Hz, and 100 w, and three time. Photolysis examinations has done in the effect of 400 w lamp and moderate pressure and 6 time, then the amount of pesticide in the samples has been measured by the High Performance Thin Layer Chromatography (HPTLC method.Results: The highest degradation in photolysis process after 1 hour in the 35 KHz was 35%, and in the 130 KHz was 63%. Degradation of carbaryl at 130 KHz is higher than 35 KHz at the same time. Carbaryl elimination was increased by arise frequency and exposure time. After 8 min in photolysis, 100% omitting has been showed.Conclusion: Degradation of carbaryl in high frequency ultrasound wavelength was more than low frequency. Degradation of carbaryl in water, combination of high frequency ultrasound wave length and UV irradiation was considerably more effective than ultrasound or ultraviolet irradiation alone.

  16. Statistical analysis using the Bayesian nonparametric method for irradiation embrittlement of reactor pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Takamizawa, Hisashi, E-mail: takamizawa.hisashi@jaea.go.jp; Itoh, Hiroto, E-mail: ito.hiroto@jaea.go.jp; Nishiyama, Yutaka, E-mail: nishiyama.yutaka93@jaea.go.jp

    2016-10-15

    In order to understand neutron irradiation embrittlement in high fluence regions, statistical analysis using the Bayesian nonparametric (BNP) method was performed for the Japanese surveillance and material test reactor irradiation database. The BNP method is essentially expressed as an infinite summation of normal distributions, with input data being subdivided into clusters with identical statistical parameters, such as mean and standard deviation, for each cluster to estimate shifts in ductile-to-brittle transition temperature (DBTT). The clusters typically depend on chemical compositions, irradiation conditions, and the irradiation embrittlement. Specific variables contributing to the irradiation embrittlement include the content of Cu, Ni, P, Si, and Mn in the pressure vessel steels, neutron flux, neutron fluence, and irradiation temperatures. It was found that the measured shifts of DBTT correlated well with the calculated ones. Data associated with the same materials were subdivided into the same clusters even if neutron fluences were increased.

  17. Method for improved decomposition of metal nitrate solutions

    Science.gov (United States)

    Haas, Paul A.; Stines, William B.

    1983-10-11

    A method for co-conversion of aqueous solutions of one or more heavy metal nitrates wherein thermal decomposition within a temperature range of about 300.degree. to 800.degree. C. is carried out in the presence of about 50 to 500% molar concentration of ammonium nitrate to total metal.

  18. Analytic method for solitary solutions of some partial differential equations

    Energy Technology Data Exchange (ETDEWEB)

    Ugurlu, Yavuz [Firat University, Department of Mathematics, 23119 Elazig (Turkey); Kaya, Dogan [Firat University, Department of Mathematics, 23119 Elazig (Turkey)], E-mail: dkaya@firat.edu.tr

    2007-10-22

    In this Letter by considering an improved tanh function method, we found some exact solutions of the clannish random walker's parabolic equation, the modified Korteweg-de Vries (KdV) equation, and the Sharma-Tasso-Olver (STO) equation with its fission and fusion, the Jaulent-Miodek equation.

  19. Analytic method for solitary solutions of some partial differential equations

    International Nuclear Information System (INIS)

    Ugurlu, Yavuz; Kaya, Dogan

    2007-01-01

    In this Letter by considering an improved tanh function method, we found some exact solutions of the clannish random walker's parabolic equation, the modified Korteweg-de Vries (KdV) equation, and the Sharma-Tasso-Olver (STO) equation with its fission and fusion, the Jaulent-Miodek equation

  20. Solutions of hyperbolic equations with the CIP-BS method

    International Nuclear Information System (INIS)

    Utsumi, Takayuki; Koga, James; Yamagiwa, Mitsuru; Yabe, Takashi; Aoki, Takayuki

    2004-01-01

    In this paper, we show that a new numerical method, the Constrained Interpolation Profile - Basis Set (CIP-BS) method, can solve general hyperbolic equations efficiently. This method uses a simple polynomial basis set that is easily extendable to any desired higher-order accuracy. The interpolating profile is chosen so that the subgrid scale solution approaches the local real solution owing to the constraints from the spatial derivatives of the master equations. Then, introducing scalar products, the linear and nonlinear partial differential equations are uniquely reduced to the ordinary differential equations for values and spatial derivatives at the grid points. The method gives stable, less diffusive, and accurate results. It is successfully applied to the continuity equation, the Burgers equation, the Korteweg-de Vries equation, and one-dimensional shock tube problems. (author)

  1. Solution of the radiative enclosure with a hybrid inverse method

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Rogerio Brittes da; Franca, Francis Henrique Ramos [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Dept. de Engenharia Mecanica], E-mail: frfranca@mecanica.ufrgs.br

    2010-07-01

    This work applies the inverse analysis to solve a three-dimensional radiative enclosure - which the surfaces are diffuse-grays - filled with transparent medium. The aim is determine the powers and locations of the heaters to attain both uniform heat flux and temperature on the design surface. A hybrid solution that couples two methods, the generalized extremal optimization (GEO) and the truncated singular value decomposition (TSVD) is proposed. The determination of the heat sources distribution is treated as an optimization problem, by GEO algorithm , whereas the solution of the system of equation, that embodies the Fredholm equation of first kind and therefore is expected to be ill conditioned, is build up through TSVD regularization method. The results show that the hybrid method can lead to a heat flux on the design surface that satisfies the imposed conditions with maximum error of less than 1,10%. The results illustrated the relevance of a hybrid method as a prediction tool. (author)

  2. Effect of gamma-irradiation of bovine serum albumin solution on the formation of zigzag film textures

    Science.gov (United States)

    Glibitskiy, Dmitriy M.; Gorobchenko, Olga A.; Nikolov, Oleg T.; Cheipesh, Tatiana A.; Roshal, Alexander D.; Zibarov, Artem M.; Shestopalova, Anna V.; Semenov, Mikhail A.; Glibitskiy, Gennadiy M.

    2018-03-01

    Formation of patterns on the surface of dried films of saline biopolymer solutions is influenced by many factors, including particle size and structure. Proteins may be modified under the influence of ionizing radiation. By irradiating protein solutions with gamma rays, it is possible to affect the formation of zigzag (Z) structures on the film surface. In our study, the films were obtained by desiccation of bovine serum albumin (BSA) solutions, which were irradiated by a 60Co gamma-source at doses ranging from 1 Gy to 12 kGy. The analysis of the resulting textures on the surface of the films was carried out by calculating the specific length of Z-structures. The results are compared against the absorption and fluorescence spectroscopy and dynamic light scattering (DLS) data. Gamma-irradiation of BSA solutions in the 1-200 Gy range practically does not influence the amount of Z-structures on the film surface. The decrease in fluorescence intensity and increase in absorbance intensity point to the destruction of BSA structure at 2 and 12 kGy, and DLS shows a more than 160% increase in particle size as a result of BSA aggregation at 2 kGy. This prevents the formation of Z-structures, which is reflected in the decrease of their specific length.

  3. A fast method for optimal reactive power flow solution

    Energy Technology Data Exchange (ETDEWEB)

    Sadasivam, G; Khan, M A [Anna Univ., Madras (IN). Coll. of Engineering

    1990-01-01

    A fast successive linear programming (SLP) method for minimizing transmission losses and improving the voltage profile is proposed. The method uses the same compactly stored, factorized constant matrices in all the LP steps, both for power flow solution and for constructing the LP model. The inherent oscillatory convergence of SLP methods is overcome by proper selection of initial step sizes and their gradual reduction. Detailed studies on three systems, including a 109-bus system, reveal the fast and reliable convergence property of the method. (author).

  4. Multigroup adjoint transport solution using the method of cyclic characteristics

    International Nuclear Information System (INIS)

    Assawaroongruengchot, M.; Marleau, G.

    2005-01-01

    The adjoint transport solution algorithm based on the method of cyclic characteristics (MOCC) is developed for the heterogeneous 2-dimensional geometries. The adjoint characteristics equation associated with a cyclic tracking line is formulated, then a closed form for adjoint angular flux can be determined. The acceleration techniques are implemented using the group-reduction and group-splitting techniques. To demonstrate the efficacy of the algorithm, the calculations are performed on the 17*17 PWR and Watanabe-Maynard benchmark problems. Comparisons of adjoint flux and k eff results obtained by MOCC and collision probability (CP) methods are performed. The mathematical relationship between pseudo-adjoint flux obtained by CP method and adjoint flux by MOCC method is presented. It appears that the pseudo-adjoint flux by CP method is equivalent to the adjoint flux by MOCC method and that the MOCC method requires lower computing time than the CP method for a single adjoint flux calculation

  5. Multigroup adjoint transport solution using the method of cyclic characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Assawaroongruengchot, M.; Marleau, G. [Ecole Polytechnique de Montreal, Institut de Genie Nucleaire, Montreal, Quebec (Canada)

    2005-07-01

    The adjoint transport solution algorithm based on the method of cyclic characteristics (MOCC) is developed for the heterogeneous 2-dimensional geometries. The adjoint characteristics equation associated with a cyclic tracking line is formulated, then a closed form for adjoint angular flux can be determined. The acceleration techniques are implemented using the group-reduction and group-splitting techniques. To demonstrate the efficacy of the algorithm, the calculations are performed on the 17*17 PWR and Watanabe-Maynard benchmark problems. Comparisons of adjoint flux and k{sub eff} results obtained by MOCC and collision probability (CP) methods are performed. The mathematical relationship between pseudo-adjoint flux obtained by CP method and adjoint flux by MOCC method is presented. It appears that the pseudo-adjoint flux by CP method is equivalent to the adjoint flux by MOCC method and that the MOCC method requires lower computing time than the CP method for a single adjoint flux calculation.

  6. Review on applied foods and analyzed methods in identification testing of irradiated foods

    International Nuclear Information System (INIS)

    Kim, Kwang Hoon; Lee, Hoo Chul; Park, Sung Hyun; Kim, Soo Jin; Kim, Kwan Soo; Jeong, Il Yun; Lee, Ju Woon; Yook, Hong Sun

    2010-01-01

    Identification methods of irradiated foods have been adopted as official test by EU and Codex. PSL, TL, ESR and GC/MS methods were registered in Korea food code on 2009 and put in force as control system of verification for labelling of food irradiation. But most generally applicable PSL and TL methods are specified applicable foods according to domestic approved items. Unlike these specifications, foods unpermitted in Korea are included in applicable items of ESR and GC/MS methods. According to recent research data, numerous food groups are possible to effective legal control by identification and these items are demanded to permit regulations for irradiation additionally. Especially, the prohibition of irradiation for meats or seafoods is not harmonized with international standards and interacts as trade friction or industrial restrictions due to unprepared domestic regulation. Hence, extension of domestic legal permission for food irradiation can contrive to related industrial development and also can reduce trade friction and enhance international competitiveness

  7. Measurement and protection of the oxidative damage induced by high-LET carbon-ion irradiation in salmon sperm DNA solution

    International Nuclear Information System (INIS)

    Moritake, T.; Nose, T.; Tsuboi, K.; Anzai, K.; Ikota, N.; Ozawa, T.; Ando, K.

    2003-01-01

    The aims of this study are to quantify the yield of hydroxyl radicals (OH) , and to evaluate the oxidative damage on DNA after high-linear energy transfer (LET) carbon-ion beams and x-rays. For this purpose, the relationship between the radiolytic yield of OH in aqueous solution and 8-hydroxydeoxyguanosine (8-OHdG) level in DNA solution were assessed after radiation. In addition, the anti-oxidative effect of 3-methyl-1-phenyl-2-pyrazonline-5-one (edaravone) on DNA was evaluated. Culture medium containing 200 mM 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) was irradiated with doses of 0 to 20 Gy with an LET of 20 to 90 keV/μm, and the yields of OH were measured using an electron spin resonance (ESR) spectrometer. Salmon sperm DNA solution at a concentration of 1.0 mg/ml was irradiated with 10 Gy of x-rays or 290 MeV/nucleon carbon-ion beams with an LET range of 20-80 keV/μm. 8-OHdG levels in the DNA solution were measured by HPLC with an electrochemical detector (ECD) after each irradiation. Edaravone was added to the DNA solution in final concentrations of 10 μM to 1 mM and 8-OHdG levels were measured by the same method after irradiation. The yield of OH by carbon-ion radiolysis increased in proportion to the absorbed dose over the range of 0 to 20 Gy, and the yield of OH decreased as LET increased logarithmically from 20 to 90 keV/μm. The level of 8-OHdG increased dose-dependently after x-ray irradiation, and it was significantly suppressed by edaravone. Furthermore, the yield of 8-OHdG and the protection efficiency by edaravone decreased as LET value increased. These unique findings provide further understanding of the indirect effect of high-LET radiation, and chemical protection of oxidative damage on DNA is important for clinical application of high-LET radiation

  8. Measurement and protection of the oxidative damage induced by high-LET carbon-ion irradiation in salmon sperm DNA solution

    Energy Technology Data Exchange (ETDEWEB)

    Moritake, T; Nose, T [University of Tsukuba, (Japan); Tsuboi, K [Institute of Clinical Medical Center, (Japan); Anzai, K; Ikota, N [National Institute of Radiological Sciences, (Japan); Ozawa, T [Redox Regulation Research Group, (Japan); Ando, K [Research Center of Charged Particle Therapy, (Japan). National Institution

    2003-07-01

    The aims of this study are to quantify the yield of hydroxyl radicals (OH) , and to evaluate the oxidative damage on DNA after high-linear energy transfer (LET) carbon-ion beams and x-rays. For this purpose, the relationship between the radiolytic yield of OH in aqueous solution and 8-hydroxydeoxyguanosine (8-OHdG) level in DNA solution were assessed after radiation. In addition, the anti-oxidative effect of 3-methyl-1-phenyl-2-pyrazonline-5-one (edaravone) on DNA was evaluated. Culture medium containing 200 mM 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) was irradiated with doses of 0 to 20 Gy with an LET of 20 to 90 keV/{mu}m, and the yields of OH were measured using an electron spin resonance (ESR) spectrometer. Salmon sperm DNA solution at a concentration of 1.0 mg/ml was irradiated with 10 Gy of x-rays or 290 MeV/nucleon carbon-ion beams with an LET range of 20-80 keV/{mu}m. 8-OHdG levels in the DNA solution were measured by HPLC with an electrochemical detector (ECD) after each irradiation. Edaravone was added to the DNA solution in final concentrations of 10 {mu}M to 1 mM and 8-OHdG levels were measured by the same method after irradiation. The yield of OH by carbon-ion radiolysis increased in proportion to the absorbed dose over the range of 0 to 20 Gy, and the yield of OH decreased as LET increased logarithmically from 20 to 90 keV/{mu}m. The level of 8-OHdG increased dose-dependently after x-ray irradiation, and it was significantly suppressed by edaravone. Furthermore, the yield of 8-OHdG and the protection efficiency by edaravone decreased as LET value increased. These unique findings provide further understanding of the indirect effect of high-LET radiation, and chemical protection of oxidative damage on DNA is important for clinical application of high-LET radiation.

  9. Dose determination in irradiated chicken meat by ESR method

    International Nuclear Information System (INIS)

    Polat, M.

    1996-01-01

    In this work, the properties of the radicals produced in chicken bones have been investigated by ESR technique to determine the amount of dose applied to the chicken meats during the food irradiation. For this goal, the drumsticks from 6-8 weeks old chickens purchased from a local market were irradiated at dose levels of 0; 2; 4; 6; 8 and 10 kGy. Then, the ESR spectra of the powder samples prepared from the bones of the drumsticks have been investigated. Unirradiated chicken bones have been observed to show a weak ESR signal of single line character. CO-2 ionic radicals of axial symmetry with g=1.9973 and g=2.0025 were observed to be produced in irradiated samples which would give rise to a three peaks ESR spectrum. In addition, the signal intensities of the samples were found to depend linearly on the irradiation dose in the dose range of 0-10 kGy. The powder samples prepared from chicken leg bones cleaned from their meats and marrow and irradiated at dose levels of 1, 2, 3, 4, 5, 6, B, 10, 12,14, 16, 1B, 20 and 22 kGy were used to get the dose-response curve. It was found that this curve has biphasic character and that the dose yield was higher in the 12-1B kGy dose range and a decrease appears in this curve over 18 kGy. The radical produced in the bones were found to be the same whether the irradiation was performed after stripping the meat and removing the marrow from the bone or before the stripping. The ESR spectra of both irradiated and non irradiated samples were investigated in the temperature range of 100 K-450 K and changes in the ESR spectra of CO-2 radical have been studied. For non irradiated samples (controls). the signal intensities were found to decrease when the temperature was increased. The same investigation has been carried out for irradiated samples and it was concluded that the signal intensities relative to the peaks of the radical spectrum increase in the temperature range of 100 K-330 K, then they decrease over 330 K. The change in the

  10. Detection of irradiated spices with a microbiological method - DEFT/APC method

    International Nuclear Information System (INIS)

    Hammerton, K.M.; Banos, C.

    1996-01-01

    The decontamination of spices that are to be used as ingredients in processed foods is necessary in order to prevent the introduction of spoilage microorganisms and more rarely disease causing organisms. Spices can be contaminated with bacteria and moulds in concentration from 10 3 to 10 8 microorganisms per gram so that, even when used in small amounts, they can contaminate food with large numbers of microorganisms. The most effective means of decontaminating spices is irradiation treatment with an absorbed radiation dose from 5 to 10 kGy. Several countries are commercially using radiation processing of spices. A microbiological screening method based on the use of the direct epifluorescent filter technique (DEFT) and the conventional aerobic plate count (APC) has been established for the detection of irradiated spices. The DEFT count enumerates the total number of contaminating microorganisms, irrespective of viability, in an untreated or treated spice sample. This paper reports recent investigations on the possibility that the inclusion of a mesophilic aerobic spore count will enable irradiated spices to be distinguished from ethylene oxide (EtO) or heat treated spices. (author)

  11. In vitro irradiation treatment - an effective method of breeding for chrysanthemum

    International Nuclear Information System (INIS)

    Dao Thanh Bang; Nguyen Hong Nhung; Nguyen Phuong Doai; Le Thi Lieu; Nguyen Pham Hung

    2011-01-01

    Recently, mutation induction is one of the an effective tool for crop breeding improvement. However, challenge for breeders is how to find suitable method for vegetative crop. Strong point of in vitro mutation breeding is reduce breeding process, easy to remove chimeric mutant after several cycle multiplication tissue culture. Based on optimal media of callus formation, regeneration and root media in chrysanthemum.The experiment of of irradiation treatment was carried out at the range doses 10, 20, 30, 50 and 70 Gy for callus of bud. From generation of M1V4, promising mutants was selected mostly in the dose of 30 Gy and bring back to in vitro for fixation and multiplication of mutant lines. Selection and evaluation of mutant lines was carried at M1V8. From CN43, crystal yellow and Taiwan purple origin varieties we received three mutants VCM1, VCM2 and VCM3 respectively. All mutant varieties have been certified as regional varieties according to decision of Ministry of Agriculture and Rural Development. The result of research show that combination between in vitro irradiation and tissue culture is effective solution for chrysanthemum breeding in particular and vegetative crop in general. (author)

  12. The use of satellite data assimilation methods in regional NWP for solar irradiance forecasting

    Science.gov (United States)

    Kurzrock, Frederik; Cros, Sylvain; Chane-Ming, Fabrice; Potthast, Roland; Linguet, Laurent; Sébastien, Nicolas

    2016-04-01

    As an intermittent energy source, the injection of solar power into electricity grids requires irradiance forecasting in order to ensure grid stability. On time scales of more than six hours ahead, numerical weather prediction (NWP) is recognized as the most appropriate solution. However, the current representation of clouds in NWP models is not sufficiently precise for an accurate forecast of solar irradiance at ground level. Dynamical downscaling does not necessarily increase the quality of irradiance forecasts. Furthermore, incorrectly simulated cloud evolution is often the cause of inaccurate atmospheric analyses. In non-interconnected tropical areas, the large amplitudes of solar irradiance variability provide abundant solar yield but present significant problems for grid safety. Irradiance forecasting is particularly important for solar power stakeholders in these regions where PV electricity penetration is increasing. At the same time, NWP is markedly more challenging in tropic areas than in mid-latitudes due to the special characteristics of tropical homogeneous convective air masses. Numerous data assimilation methods and strategies have evolved and been applied to a large variety of global and regional NWP models in the recent decades. Assimilating data from geostationary meteorological satellites is an appropriate approach. Indeed, models converting radiances measured by satellites into cloud properties already exist. Moreover, data are available at high temporal frequencies, which enable a pertinent cloud cover evolution modelling for solar energy forecasts. In this work, we present a survey of different approaches which aim at improving cloud cover forecasts using the assimilation of geostationary meteorological satellite data into regional NWP models. Various approaches have been applied to a variety of models and satellites and in different regions of the world. Current methods focus on the assimilation of cloud-top information, derived from infrared

  13. Determination of plutonium in pure plutonium nitrate solutions - Gravimetric method

    International Nuclear Information System (INIS)

    1987-01-01

    This International Standard specifies a precise and accurate gravimetric method for determining the concentration of plutonium in pure plutonium nitrate solutions and reference solutions, containing between 100 and 300 g of plutonium per litre, in a nitric acid medium. The weighed portion of the plutonium nitrate is treated with sulfuric acid and evaporated to dryness. The plutonium sulfate is decomposed and formed to oxide by heating in air. The oxide is ignited in air at 1200 to 1250 deg. C and weighed as stoichiometric plutonium dioxide, which is stable and non-hygroscopic

  14. Solution methods for large systems of linear equations in BACCHUS

    International Nuclear Information System (INIS)

    Homann, C.; Dorr, B.

    1993-05-01

    The computer programme BACCHUS is used to describe steady state and transient thermal-hydraulic behaviour of a coolant in a fuel element with intact geometry in a fast breeder reactor. In such computer programmes generally large systems of linear equations with sparse matrices of coefficients, resulting from discretization of coolant conservation equations, must be solved thousands of times giving rise to large demands of main storage and CPU time. Direct and iterative solution methods of the systems of linear equations, available in BACCHUS, are described, giving theoretical details and experience with their use in the programme. Besides use of a method of lines, a Runge-Kutta-method, for solution of the partial differential equation is outlined. (orig.) [de

  15. Acceleration of monte Carlo solution by conjugate gradient method

    International Nuclear Information System (INIS)

    Toshihisa, Yamamoto

    2005-01-01

    The conjugate gradient method (CG) was applied to accelerate Monte Carlo solutions in fixed source problems. The equilibrium model based formulation enables to use CG scheme as well as initial guess to maximize computational performance. This method is available to arbitrary geometry provided that the neutron source distribution in each subregion can be regarded as flat. Even if it is not the case, the method can still be used as a powerful tool to provide an initial guess very close to the converged solution. The major difference of Monte Carlo CG to deterministic CG is that residual error is estimated using Monte Carlo sampling, thus statistical error exists in the residual. This leads to a flow diagram specific to Monte Carlo-CG. Three pre-conditioners were proposed for CG scheme and the performance was compared with a simple 1-D slab heterogeneous test problem. One of them, Sparse-M option, showed an excellent performance in convergence. The performance per unit cost was improved by four times in the test problem. Although direct estimation of efficiency of the method is impossible mainly because of the strong problem-dependence of the optimized pre-conditioner in CG, the method seems to have efficient potential as a fast solution algorithm for Monte Carlo calculations. (author)

  16. Photodegradation of gemfibrozil in aqueous solution under UV irradiation: kinetics, mechanism, toxicity, and degradation pathways.

    Science.gov (United States)

    Ma, Jingshuai; Lv, Wenying; Chen, Ping; Lu, Yida; Wang, Fengliang; Li, Fuhua; Yao, Kun; Liu, Guoguang

    2016-07-01

    The lipid regulator gemfibrozil (GEM) has been reported to be persistent in conventional wastewater treatment plants. This study investigated the photolytic behavior, toxicity of intermediate products, and degradation pathways of GEM in aqueous solutions under UV irradiation. The results demonstrated that the photodegradation of GEM followed pseudo-first-order kinetics, and the pseudo-first-order rate constant was decreased markedly with increasing initial concentrations of GEM and initial pH. The photodegradation of GEM included direct photolysis via (3)GEM(*) and self-sensitization via ROS, where the contribution rates of degradation were 0.52, 90.05, and 8.38 % for ·OH, (1)O2, and (3)GEM(*), respectively. Singlet oxygen ((1)O2) was evidenced by the molecular probe compound, furfuryl alcohol (FFA), and was identified as the primary reactive species in the photolytic process. The steady-state concentrations of (1)O2 increased from (0.324 ± 0.014) × 10(-12) to (1.021 ± 0.040) × 10(-12) mol L(-1), as the initial concentrations of GEM were increased from 5 to 20 mg L(-1). The second-order rate constant for the reaction of GEM with (1)O2 was calculated to be 2.55 × 10(6) M(-1) s(-1). The primary transformation products were identified using HPLC-MS/MS, and possible photodegradation pathways were proposed by hydroxylation, aldehydes reactions, as well as the cleavage of ether side chains. The toxicity of phototransformation product evaluation revealed that photolysis potentially provides a critical pathway for GEM toxicity reduction in potable water and wastewater treatment facilities.

  17. Detection of irradiated cheese and exotic fruits by a simple routine control method

    International Nuclear Information System (INIS)

    Spiegelberg, A.; Schulzki, G.; Helle, N.; Boegl, K.W.; Schreiber, G.A.

    1993-01-01

    The results demonstrate very clearly that Florisil chromatography is a suitable routine method to detect irradiation treatment in Camembert, mango seeds and avocado flesh. Inspite of excluding 1-14:1 as marker for irradiation treatment on account of fat attendant flavour compounds in fruits, an unequivocal revelation of irradiated samples was possible because the most important radiation-induced hydrocarbons 1,7-26:2 and 8-14:1 (arising from oleic acid) could be clearly detected in both fruits. In addition, high amounts of 1-16:1 from stearic acid are present in irradiated mango and 6,9-17:2 from linoleic acid in avocado. (orig.)

  18. Development, fundamentals and objective of half-body irradiation as a method of systematic tumor therapy

    International Nuclear Information System (INIS)

    Eichhorn, H.J.

    1988-01-01

    A review is given on (1) the development of systemic radiotherapy - total body irradiation as well as sequential half-body irradiation in cases of palliative and curative treatment, resp., (2) radiobiological fundamentals of action and limits of the method, (3) clinical results of upper and lower half-body irradiation, resp., as palliative treatment of solid tumors, (4) studies of the prevention of radiation pneumonitis without decreasing radiation dose and (5) proposals for modification, improvement and combination of upper and lower half-body irradiation with other procedures such as hyperthermia and chemotherapy. 48 refs

  19. Amarginal contribution of selected carotenoids to the supression of UV-irradiation-induced lecithin peroxidation in hexane solution

    Directory of Open Access Journals (Sweden)

    DRAGAN CVETKOVIC

    2007-03-01

    Full Text Available The aim of this work was to study the anticipated antioxidant role of four selected carotenoids in mixtures with lecithin lipoidal compounds in hexane solution, under continuous UV-irradiation in three different ranges (UV-A, UV-B and UV-C. Two carotenes (b-carotene and licopene and two xantophylls (lutein and neoxanthin were employed to control the lipid peroxidation process generated by UV-irradiation, by scavenging the involved free radicals. The results show that while carotenoids undergo a substantial, structural dependent destruction (bleaching, which is highly dependent on energy of the UV-photons, their contribution to the expected suppression of lecithin peroxidation is of marginal importance, not exceeding a maximum of 20%. The marginal antioxidant behaviour has been attributed to a highly unordered hexane solution, where the scavenging action of the carotenoids becomes less competitive.

  20. Forecast Method of Solar Irradiance with Just-In-Time Modeling

    Science.gov (United States)

    Suzuki, Takanobu; Goto, Yusuke; Terazono, Takahiro; Wakao, Shinji; Oozeki, Takashi

    PV power output mainly depends on the solar irradiance which is affected by various meteorological factors. So, it is required to predict solar irradiance in the future for the efficient operation of PV systems. In this paper, we develop a novel approach for solar irradiance forecast, in which we introduce to combine the black-box model (JIT Modeling) with the physical model (GPV data). We investigate the predictive accuracy of solar irradiance over wide controlled-area of each electric power company by utilizing the measured data on the 44 observation points throughout Japan offered by JMA and the 64 points around Kanto by NEDO. Finally, we propose the application forecast method of solar irradiance to the point which is difficulty in compiling the database. And we consider the influence of different GPV default time on solar irradiance prediction.

  1. γ irradiation of aqueous solutions of human hemoglobin in atmospheres of air and argon

    International Nuclear Information System (INIS)

    Puchala, M.; Szweda-Lewandowska, Z.; Leyko, W.

    1979-01-01

    In this study, the degrees of destruction of hemoglobin irradiated in atmospheres of air and argon were compared. Hemoglobin preparations were irradiated in the forms: oxyhemoglobin (HbO 2 ) deoxyhemoglobin (Hb 2+ ) and methemoglobin (MetHb) applying doses of 0.5 to 5 Mrad. The degree of hemoglobin destruction was estimate on the basis of changes in the values of the absorption coefficient at the Soret band, the absorption ratio A 505 /A 563 determined after conversion of irradiated preparations into MetHb, absorption coefficinets for pyridine hemochromogen obtained from irradiated preparations, and changes in parameters characterizing the hemoglobin oxygenation reaction (log p/sub 1/2/O 2 and the Hill n coefficient). The calculated oxygen enhancement ratios S were generally higher than 1 for the parameters estimated. This indicates that the presence of oxygen during irradiation enhances hemoglobin destruction

  2. Pollen irradiation method to obtain mutants in cucumber

    International Nuclear Information System (INIS)

    Iida, S.; Amano, E.

    1988-01-01

    Seed irradiation for mutation induction in dioecious crops like cucumber is not very useful because chimerism of the mutated tissues makes the segregation of mutants in the M 2 generation nearly impossible. This problem does not exist with pollen irradiation. Cucumber (Cucumis sativus L. var. Nishikisuyo) was used for a model experiment. The petals of male and female flowers were closed by pinching with binding wire before flowering to prevent pollination by insects. On the flowering day, the male flowers were collected and irradiated with 1kR to 10 kR of acute gamma rays (137-Cs), then used to pollinate the female flowers. The M 1 seeds thus obtained are not chimeric but heterozygous for induced mutations. When planted, no mutant phenotype appeared. Selfing within a plant lead to segregation of mutants in the M 2 generation. Seedling examination revealed eight mutants. One mutant line, in which the shape of leaves changed from pentagonal to round heart shape, was found under field conditions. The optimal dose for pollen irradiation seems to be between 2 kR and 4kR

  3. Estimation of dose in irradiated chicken bone by ESR method

    International Nuclear Information System (INIS)

    Tanabe, Hiroko; Hougetu, Daisuke

    1998-01-01

    The author studied the conditions needed to routinely estimate the radiation dose in chicken bone by repeated re-irradiation and measuring ESR signals. Chicken meat containing bone was γ-irradiated at doses of up to 3kGy, accepted as the commercially used dose. The results show that points in sample preparation and ESR measurement are as follows: Both ends of bone are cut off and central part of compact bone is used for experiment. To obtain accurate ESR spectrum, marrow should be scraped out completely. Sample bone fragments of 1-2mm particle size and ca.100mg are recommended to obtain stable and maximum signal. In practice, by re-irradiating up to 5kGy and extrapolating data of the signal intensity to zero using linear regression analysis, radiation dose is estimated. For example, in one experiment, estimated doses of chicken bones initially irradiated at 3.0kGy, 1.0kGy, 0.50kGy and 0.25kGy were 3.4kGy, 1.3kGy, 0.81kGy and 0.57kGy. (author)

  4. A simple graphical method for deriving kinetics of repair from fractionated and protracted irradiations

    International Nuclear Information System (INIS)

    Scalliet, P.; Schueren, E. van der; Erfmann, R.K.L.; Landuyt, W.

    1988-01-01

    The authors present a method for the derivation of the time constant of repair from fractionated and protracted irradiations, using formulae based on those derived by Dale (1985) and Liversage (1969) establishing the correlation between the biological effects of low dose rate and acute fractionated irradiation. (UK)

  5. The irradiation as a quarantine method for the treatment of fresh fruits

    International Nuclear Information System (INIS)

    Kaupert, Norma L.

    1999-01-01

    The irradiation is proposed as an alternative to chemical or other physical methods for the quarantine of fresh fruit. The case of the products of the Southern part of Argentina is analysed and the economical and financial parameters for the installation and the operation of an irradiation plant are estimated. The costs are compared to those of a chemical quarantine system. (author)

  6. A new method for the solution of the Schroedinger equation

    International Nuclear Information System (INIS)

    Amore, Paolo; Aranda, Alfredo; De Pace, Arturo

    2004-01-01

    We present a new method for the solution of the Schroedinger equation applicable to problems of a non-perturbative nature. The method works by identifying three different scales in the problem, which then are treated independently: an asymptotic scale, which depends uniquely on the form of the potential at large distances; an intermediate scale, still characterized by an exponential decay of the wavefunction; and, finally, a short distance scale, in which the wavefunction is sizable. The notion of optimized perturbation is then used in the last two regimes. We apply the method to the quantum anharmonic oscillator and find it suitable to treat both energy eigenvalues and wavefunctions, even for strong couplings

  7. Physical nature of structural and phase transformations in Cu-Al α solid solutions upon low-temperature irradiation and subsequent annealing

    Science.gov (United States)

    Petrenko, P. V.; Kulish, N. P.; Mel'nikova, N. A.; Grabovskii, Yu. E.

    2013-12-01

    Methods of X-ray diffraction analysis and measurements of residual resistivity have been used to study effects of electron irradiation in the temperature range of 250-330 K on the structural and phase state of the Cu-15 at % Al solid solution. The results obtained are explained by the presence in the Cu-Al alloys of an inhomogeneous short-range order of two types, i.e., low-temperature, α2 type; and high-temperature, γ2 type.

  8. The method of estimating the irradiated lung volume in primary breast irradiation

    International Nuclear Information System (INIS)

    Leite, Miguel Torres Teixeira; Marques, Iara Silva; Geraldo, Jony Marques

    1999-01-01

    Tangential breast fields irradiation usually includes some volume of lung and it is occasionally associated with pneumonitis. The estimation of the amount of lung irradiated can be determined measuring the central lung distance (CLD) by the port films, and it must be inferior to 2.5 cm. The purpose of this study was to determine through a linear regression analysis the relationship between CLD and the geometrical parameters of the treatment, and to develop an equation to predict this volume. The studied population consisted of 100 patients who received definitive radiation for clinical stage I and II breast cancer between January, 1996 and June, 1997. According to the contour of the breast and thorax was determined the angle of the tangential fields. In 71% of the patients the CLD measured by the portal films were superior to 2.5 cm, requiring a new beam arrangement. We develop a simple and convenient quantitative model to predict the irradiated lung volume based on portal films. We need further analysis in order to include variables and antomical variations. (author)

  9. Rate constant for reaction of vitamin C with protein radicals in γ-irradiated aqueous albumin solution at 295K

    International Nuclear Information System (INIS)

    Miyazaki, Tetsuo; Yoshimura, Toru; Mita, Kazuya; Suzuki, Keiji; Watanabe, Masami

    1995-01-01

    When an aqueous solution of albumin (0.1 kg dm -3 ) is irradiated by γ-rays at 295 K, albumin radicals with a long lifetime are observed by ESR. The reaction of vitamin C with the albumin radicals has been studied at 295 K in the albumin solution, which is considered as a model of cells. The rate constant for the reaction of vitamin C with the albumin radicals was measured as 0.014 dm 3 mol -1 S -1 , which is much smaller than the reported constants (10 6 -10 10 dm 3 mol -1 s -1 ) for the reaction of vitamin C with radicals in a dilute aqueous solution. The small rate constant for the reaction of vitamin C is ascribed to the reaction in polymer coils in the albumin solution, since vitamin C and albumin radicals diffuse very slowly in the coils. (author)

  10. Improved parallel solution techniques for the integral transport matrix method

    Energy Technology Data Exchange (ETDEWEB)

    Zerr, R. Joseph, E-mail: rjz116@psu.edu [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA (United States); Azmy, Yousry Y., E-mail: yyazmy@ncsu.edu [Department of Nuclear Engineering, North Carolina State University, Burlington Engineering Laboratories, Raleigh, NC (United States)

    2011-07-01

    Alternative solution strategies to the parallel block Jacobi (PBJ) method for the solution of the global problem with the integral transport matrix method operators have been designed and tested. The most straightforward improvement to the Jacobi iterative method is the Gauss-Seidel alternative. The parallel red-black Gauss-Seidel (PGS) algorithm can improve on the number of iterations and reduce work per iteration by applying an alternating red-black color-set to the subdomains and assigning multiple sub-domains per processor. A parallel GMRES(m) method was implemented as an alternative to stationary iterations. Computational results show that the PGS method can improve on the PBJ method execution time by up to 10´ when eight sub-domains per processor are used. However, compared to traditional source iterations with diffusion synthetic acceleration, it is still approximately an order of magnitude slower. The best-performing cases are optically thick because sub-domains decouple, yielding faster convergence. Further tests revealed that 64 sub-domains per processor was the best performing level of sub-domain division. An acceleration technique that improves the convergence rate would greatly improve the ITMM. The GMRES(m) method with a diagonal block pre conditioner consumes approximately the same time as the PBJ solver but could be improved by an as yet undeveloped, more efficient pre conditioner. (author)

  11. Improved parallel solution techniques for the integral transport matrix method

    International Nuclear Information System (INIS)

    Zerr, R. Joseph; Azmy, Yousry Y.

    2011-01-01

    Alternative solution strategies to the parallel block Jacobi (PBJ) method for the solution of the global problem with the integral transport matrix method operators have been designed and tested. The most straightforward improvement to the Jacobi iterative method is the Gauss-Seidel alternative. The parallel red-black Gauss-Seidel (PGS) algorithm can improve on the number of iterations and reduce work per iteration by applying an alternating red-black color-set to the subdomains and assigning multiple sub-domains per processor. A parallel GMRES(m) method was implemented as an alternative to stationary iterations. Computational results show that the PGS method can improve on the PBJ method execution time by up to 10´ when eight sub-domains per processor are used. However, compared to traditional source iterations with diffusion synthetic acceleration, it is still approximately an order of magnitude slower. The best-performing cases are optically thick because sub-domains decouple, yielding faster convergence. Further tests revealed that 64 sub-domains per processor was the best performing level of sub-domain division. An acceleration technique that improves the convergence rate would greatly improve the ITMM. The GMRES(m) method with a diagonal block pre conditioner consumes approximately the same time as the PBJ solver but could be improved by an as yet undeveloped, more efficient pre conditioner. (author)

  12. All-proportional solid-solution Rh–Pd–Pt alloy nanoparticles by femtosecond laser irradiation of aqueous solution with surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Md. Samiul Islam, E-mail: samiul-phy@ru.ac.bd; Nakamura, Takahiro; Sato, Shunichi [Tohoku University, Institute of Multidisciplinary Research for Advanced Materials (Japan)

    2015-06-15

    Formation of Rh–Pd–Pt solid-solution alloy nanoparticles (NPs) by femtosecond laser irradiation of aqueous solution in the presence of polyvinylpyrrolidone (PVP) or citrate as a stabilizer was studied. It was found that the addition of surfactant (PVP or citrate) significantly contributed to reduce the mean size of the particles to 3 nm for PVP and 10 nm for citrate, which was much smaller than that of the particles fabricated without any surfactants (20 nm), and improved the dispersion state as well as the colloidal stability. The solid-solution formation of the Rh–Pd–Pt alloy NPs was confirmed by the XRD results that the diffraction pattern was a single peak, which was found between the positions corresponding to each pure Rh, Pd, and Pt NPs. Moreover, all the elements were homogeneously distributed in every particle by STEM-EDS elemental mapping, strongly indicating the formation of homogeneous solid-solution alloy. Although the Rh–Pd–Pt alloy NPs fabricated with PVP was found to be Pt rich by EDS observation, the composition of NPs fabricated with citrate almost exactly preserved the feeding ratio of ions in the mixed solution. To our best knowledge, these results demonstrated for the first time, the formation of all-proportional solid-solution Rh–Pd–Pt alloy NPs with well size control.

  13. A method to calibrate a solar pyranometer for measuring reference diffuse irradiance

    Energy Technology Data Exchange (ETDEWEB)

    Reda, I.; Stoffel, T.; Myers, D. [National Renewable Energy Laboratory, Golden, CO (United States)

    2003-02-01

    Accurate pyranometer calibrations, traceable to internationally recognized standards, are critical for solar irradiance measurements. One calibration method is the component summation, where the pyranometers are calibrated outdoors under clear sky conditions, and the reference global solar irradiance is calculated as the sum of two reference components, the diffuse and subtended beam solar irradiances. The beam component is measured with pyrheliometers traceable to the World Radiometric Reference, while there is no internationally recognized reference for the diffuse component. In the absence of such a reference, we present a method to consistently calibrate pyranometers for measuring the diffuse component with an estimated uncertainty of {+-} (3% of reading +1 W/m{sup 2}). The method is based on using a modified shade/unshade method, and pyranometers with less than 1 W/m{sup 2} thermal offset errors. We evaluated the consistency of our method by calibrating three pyranometers four times. Calibration results show that the responsivity change is within {+-} 0.52% for the three pyranometers. We also evaluated the effect of calibrating pyranometers unshaded, then using them shaded to measure diffuse irradiance. We calibrated three unshaded pyranometers using the component summation method. Their outdoor measurements of clear sky diffuse irradiance, from sunrise to sundown, showed that the three calibrated pyranometers can be used to measure the diffuse irradiance to within {+-} 1.4 W/m{sup 2} variation from the reference irradiance. (author)

  14. Hybrid Fundamental Solution Based Finite Element Method: Theory and Applications

    Directory of Open Access Journals (Sweden)

    Changyong Cao

    2015-01-01

    Full Text Available An overview on the development of hybrid fundamental solution based finite element method (HFS-FEM and its application in engineering problems is presented in this paper. The framework and formulations of HFS-FEM for potential problem, plane elasticity, three-dimensional elasticity, thermoelasticity, anisotropic elasticity, and plane piezoelectricity are presented. In this method, two independent assumed fields (intraelement filed and auxiliary frame field are employed. The formulations for all cases are derived from the modified variational functionals and the fundamental solutions to a given problem. Generation of elemental stiffness equations from the modified variational principle is also described. Typical numerical examples are given to demonstrate the validity and performance of the HFS-FEM. Finally, a brief summary of the approach is provided and future trends in this field are identified.

  15. Solution of the isotopic depletion equation using decomposition method and analytical solution

    Energy Technology Data Exchange (ETDEWEB)

    Prata, Fabiano S.; Silva, Fernando C.; Martinez, Aquilino S., E-mail: fprata@con.ufrj.br, E-mail: fernando@con.ufrj.br, E-mail: aquilino@lmp.ufrj.br [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear

    2011-07-01

    In this paper an analytical calculation of the isotopic depletion equations is proposed, featuring a chain of major isotopes found in a typical PWR reactor. Part of this chain allows feedback reactions of (n,2n) type. The method is based on decoupling the equations describing feedback from the rest of the chain by using the decomposition method, with analytical solutions for the other isotopes present in the chain. The method was implemented in a PWR reactor simulation code, that makes use of the nodal expansion method (NEM) to solve the neutron diffusion equation, describing the spatial distribution of neutron flux inside the reactor core. Because isotopic depletion calculation module is the most computationally intensive process within simulation systems of nuclear reactor core, it is justified to look for a method that is both efficient and fast, with the objective of evaluating a larger number of core configurations in a short amount of time. (author)

  16. Solution of the isotopic depletion equation using decomposition method and analytical solution

    International Nuclear Information System (INIS)

    Prata, Fabiano S.; Silva, Fernando C.; Martinez, Aquilino S.

    2011-01-01

    In this paper an analytical calculation of the isotopic depletion equations is proposed, featuring a chain of major isotopes found in a typical PWR reactor. Part of this chain allows feedback reactions of (n,2n) type. The method is based on decoupling the equations describing feedback from the rest of the chain by using the decomposition method, with analytical solutions for the other isotopes present in the chain. The method was implemented in a PWR reactor simulation code, that makes use of the nodal expansion method (NEM) to solve the neutron diffusion equation, describing the spatial distribution of neutron flux inside the reactor core. Because isotopic depletion calculation module is the most computationally intensive process within simulation systems of nuclear reactor core, it is justified to look for a method that is both efficient and fast, with the objective of evaluating a larger number of core configurations in a short amount of time. (author)

  17. Microbiological Method (DEFT/APC) For The Detection Of Irradiated Foods In Egypt

    International Nuclear Information System (INIS)

    Osman, M.E.; Abo El-Nasr, A.; Abo El Nour, S.A.; Hammad, A.; Ibrahim, H.M.A.

    2013-01-01

    The applicability of a microbiological screening method based on the comparison of the count obtained by the direct epi fluorescent filter technique (DEFT) with the count obtained by the conventional aerobic plate count (APC) for the detection of three kinds of irradiated foodstuffs (black pepper, strawberry, de-boned chicken meat) in Egypt was evaluated. The detection method was carried out immediately after irradiation and during subsequent storage. The results revealed that for irradiation doses of 5 kGy or higher, the DEFT/APC difference of around 2 log units or more could be a suitable criterion for judging black pepper samples as irradiated. DEFT/APC difference of around 2 log units or more could be used as a criterion for irradiation processing of strawberry at dose level of 2 kGy or higher. The DEFT/APC difference of around 2.5 log units or more could be indicated that fresh and frozen de-boned chicken meat samples had been irradiated at least at 3 and 6 kGy or higher, respectively. In general, the results showed that this method had the potential to detect irradiated food samples either immediately after irradiation or throughout the storage period.

  18. Effect of solute atoms on collision cascades in copper and molybdenum irradiated with self-ions

    International Nuclear Information System (INIS)

    English, C.A.; Eyre, B.L.; Wadley, H.; Stathopoulos, A.Y.

    1975-01-01

    An examination of the effect material purity has on the numbers and sizes of the vacancy loops formed in collision cascades produced by self-ion irradiation of copper and molybdenum is reported. It is shown that substitutional and interstitial impurities both markedly reduce the damage generated in molybdenum by 60 keV Mo + ions but little effect is seen in copper irradiated by 30 keV Cu + ions. These results are compared with recent observations of vacancy defects in type 316 stainless steel following irradiation with 40-200 keV Cr + . The comparison highlights the much lower vacancy concentration retained in visible clusters in the complex alloy

  19. Linear facility location in three dimensions - Models and solution methods

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schöbel, Anita

    2002-01-01

    We consider the problem of locating a line or a line segment in three-dimensional space, such that the sum of distances from the facility represented by the line (segment) to a given set of points is minimized. An example is planning the drilling of a mine shaft, with access to ore deposits through...... horizontal tunnels connecting the deposits and the shaft. Various models of the problem are developed and analyzed, and efficient solution methods are given....

  20. Solution Methods for the Periodic Petrol Station Replenishment Problem

    OpenAIRE

    C Triki

    2013-01-01

    In this paper we introduce the Periodic Petrol Station Replenishment Problem (PPSRP) over a T-day planning horizon and describe four heuristic methods for its solution. Even though all the proposed heuristics belong to the common partitioning-then-routing paradigm, they differ in assigning the stations to each day of the horizon. The resulting daily routing problems are then solved exactly until achieving optimalization. Moreover, an improvement procedure is also developed with the aim of ens...

  1. Method of solution mining subsurface orebodies to reduce restoration activities

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, G.J.

    1984-01-24

    A method of solution mining is claimed wherein a lixiviant containing both leaching and oxidizing agents is injected into the subsurface orebody. The composition of the lixiviant is changed by reducing the level of oxidizing agent to zero so that soluble species continue to be removed from the subsurface environment. This reduces the uranium level of the ground water aquifer after termination of the lixiviant injection.

  2. Method for coating a resinous coating material. [electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ino, T; Fujioka, S; Mibae, J; Takahashi, M

    1968-07-13

    The strength, flexibility and durability of a vinyl chloride resin, acryl resin and the like are improved. This method of application comprises the steps of applying and thereafter radically curing a mixture composed of a polymer (II) having double bond(s) on its side chain and an ethylenic unsaturated monomer, said polymer (II) being obtained by the reaction between an unsaturated carboxylic acid or anhydride represented by the formula XCH = CHY (X = (CH/sub 2/)sub(n)COOH, where 0 <= n <= 2, Y = COOR/sub 1/ or R/sub 2/(R/sub 1/ and R/sub 2/ are hydrogen or an alkyl group having from 1 to 10 atoms of carbon)) and the acrylic copolymer (I), containing a hydroxyl group, obtained by copolymerization of 10 to 50% by weight of at least one selected from the group of beta-hydroxy alkyl acrylate, beta-hydroxy alkyl methacrylate, N-methylol acrylamide and N-methylol methacryl amide with at least one selected from the group of acrylic ester, methacrylic ester and stylene. The copolymer (I) can be obtained by the usual radical polymerization such as bulk polymerization, solution polymerization, suspension polymerization or the like. The polymer (II) is dissolved in the ethylenic unsaturated monomer and radically cured with radical polymerization catalysts or electron beams, etc. The energy range of the electron beams may be 0.1 to 3 MeV. Any type of electron accelerator may be used.

  3. Experience of the irradiation method under mixed gas (95% O2 plus 5% CO2) inhalation

    International Nuclear Information System (INIS)

    Ikeda, Michio; Tazaki, Eio

    1978-01-01

    The irradiation method under mixed gas of 95% O 2 plus CO 2 inhalation at one atomosphere was discussed to improve therapeutic results, in malignant tumors which are not greatly sensitive to irradiation. Randomized study was done in each attending institute, with common protocols. As a result, no positive effect was recognized in irradiation method under mixed gas inhalation with daily dose of 200 rad and 5 fractions per week, which is widely used clinically. But when irradiation dose was increased up to 500 to 600 rad per fraction, effect of the mixed gas was remarkable. But against this, observing for years, results in irradiation under mixed gas inhalation were not always related to the improvement of the long term survival. (author)

  4. Soil solution dynamics of Cu and Zn in a Cu- and Zn-polluted soil as influenced by gamma-irradiation and Cu-Zn interaction.

    Science.gov (United States)

    Luo, Y M; Yan, W D; Christie, P

    2001-01-01

    A pot experiment was conducted to study soil solution dynamics of Cu and Zn in a Cu/Zn-polluted soil as influenced by gamma-irradiation and Cu-Zn interaction. A slightly acid sandy loam was amended with Cu and Zn (as nitrates) either singly or in combination (100 mg Cu and 150 mg Zn kg(-1) soil) and was then gamma-irradiated (10 kGy). Unamended and unirradiated controls were included, and spring barley (Hordeum vulgare L. cv. Forrester) was grown for 50 days. Soil solution samples obtained using soil moisture samplers immediately before transplantation and every ten days thereafter were used directly for determination of Cu, Zn, pH and absorbance at 360 nm (A360). Cu and Zn concentrations in the solution of metal-polluted soil changed with time and were affected by gamma-irradiation and metal interaction. gamma-Irradiation raised soil solution Cu substantially but generally decreased soil solution Zn. These trends were consistent with increased dissolved organic matter (A360) and solution pH after gamma-irradiation. Combined addition of Cu and Zn usually gave higher soil solution concentrations of Cu or Zn compared with single addition of Cu or Zn in gamma-irradiated and non-irradiated soils, indicating an interaction between Cu and Zn. Cu would have been organically complexed and consequently maintained a relatively high concentration in the soil solution under higher pH conditions. Zn tends to occur mainly as free ion forms in the soil solution and is therefore sensitive to changes in pH. The extent to which gamma-irradiation and metal interaction affected solubility and bioavailability of Cu and Zn was a function of time during plant growth. Studies on soil solution metal dynamics provide very useful information for understanding metal mobility and bioavailability.

  5. Formation of chromium oxide nanoparticles by gamma irradiation of chromate solutions

    International Nuclear Information System (INIS)

    Alrehaily, L.M.; Joseph, J.M.; Wren, J.C.; Guzonas, D.A.

    2012-09-01

    One of the operational and safety challenges of nuclear reactors is the corrosion of coolant system materials. Corrosion products released into the reactor coolant circulate through the reactor core and can be deposited on surfaces there where they can be neutron activated. If these radioactive species are then released into the coolant, they can migrate out of the core and deposit on piping and components located outside the biological shield of the reactor core. These activated corrosion products pose a radiological hazard to plant workers. The radiolysis of water produces redox-active radicals and molecules that can interact very effectively with metallic corrosion products, changing their oxidation states. The solubility of hydrated metal species varies considerably depending on their oxidation state. For example, ferrous iron is several orders of magnitude more soluble than ferric iron at acidic and neutral pHs, while Cr VI species are much more soluble than Cr III species at all pHs. Conversion of more soluble metal ions to less soluble ions will promote precipitation of metal oxide colloidal particles. The conversion of a dissolved ion to a particle will change the transport behaviour of corrosion products and their removal efficiency from system surfaces or by a purification system. Hence, a well-founded understanding of the behaviour of corrosion product ions in a radiolytic environment is very important in assessing their transport behaviour in a reactor coolant system, and the effectiveness of measures to limit radioactive contamination of the coolant system. The formation of chromium oxide nanoparticles by gamma radiolysis of Cr VI (aq) (CrO 4 2- or Cr 2 O 7 2- ) solutions was investigated as a function of pH and Cr VI (aq) concentration using a range of chemical and particle analysis techniques. The results show that Cr VI (aq) is reduced to less soluble Cr III species by reducing radiolysis products (e.g., .eaq - ). These insoluble Cr III species

  6. Computer methods in physics 250 problems with guided solutions

    CERN Document Server

    Landau, Rubin H

    2018-01-01

    Our future scientists and professionals must be conversant in computational techniques. In order to facilitate integration of computer methods into existing physics courses, this textbook offers a large number of worked examples and problems with fully guided solutions in Python as well as other languages (Mathematica, Java, C, Fortran, and Maple). It’s also intended as a self-study guide for learning how to use computer methods in physics. The authors include an introductory chapter on numerical tools and indication of computational and physics difficulty level for each problem.

  7. Application of accelerated evaluation method of alteration temperature and constant dose rate irradiation on bipolar linear regulator LM317

    International Nuclear Information System (INIS)

    Deng Wei; Wu Xue; Wang Xin; Zhang Jinxin; Zhang Xiaofu; Zheng Qiwen; Ma Wuying; Lu Wu; Guo Qi; He Chengfa

    2014-01-01

    With different irradiation methods including high dose rate irradiation, low dose rate irradiation, alteration temperature and constant dose rate irradiation, and US military standard constant high temperature and constant dose rate irradiation, the ionizing radiation responses of bipolar linear regulator LM317 from three different companies were investigated under the operating and zero biases. The results show that compared with constant high temperature and constant dose rate irradiation method, the alteration temperature and constant dose rate irradiation method can not only very rapidly and accurately evaluate the dose rate effect of three bipolar linear regulators, but also well simulate the damage of low dose rate irradiation. Experiment results make the alteration temperature and constant dose rate irradiation method successfully apply to bipolar linear regulator. (authors)

  8. A general solution strategy of modified power method for higher mode solutions

    International Nuclear Information System (INIS)

    Zhang, Peng; Lee, Hyunsuk; Lee, Deokjung

    2016-01-01

    A general solution strategy of the modified power iteration method for calculating higher eigenmodes has been developed and applied in continuous energy Monte Carlo simulation. The new approach adopts four features: 1) the eigen decomposition of transfer matrix, 2) weight cancellation for higher modes, 3) population control with higher mode weights, and 4) stabilization technique of statistical fluctuations using multi-cycle accumulations. The numerical tests of neutron transport eigenvalue problems successfully demonstrate that the new strategy can significantly accelerate the fission source convergence with stable convergence behavior while obtaining multiple higher eigenmodes at the same time. The advantages of the new strategy can be summarized as 1) the replacement of the cumbersome solution step of high order polynomial equations required by Booth's original method with the simple matrix eigen decomposition, 2) faster fission source convergence in inactive cycles, 3) more stable behaviors in both inactive and active cycles, and 4) smaller variances in active cycles. Advantages 3 and 4 can be attributed to the lower sensitivity of the new strategy to statistical fluctuations due to the multi-cycle accumulations. The application of the modified power method to continuous energy Monte Carlo simulation and the higher eigenmodes up to 4th order are reported for the first time in this paper. -- Graphical abstract: -- Highlights: •Modified power method is applied to continuous energy Monte Carlo simulation. •Transfer matrix is introduced to generalize the modified power method. •All mode based population control is applied to get the higher eigenmodes. •Statistic fluctuation can be greatly reduced using accumulated tally results. •Fission source convergence is accelerated with higher mode solutions.

  9. Catalytic and physical properties of γ-irradiated catalase in dilute solution

    International Nuclear Information System (INIS)

    Gasyna, Z.; Bachman, S.

    1974-01-01

    The catalytic and physical properties of irradiated beef liver catalase have been studied. Modification of the enzyme by γ-rays brings about its reducibility by dithionite. The decrease of the catalytic activity is found to correspond to the decrease in the content of nonreducible catalase. Microaggregates of catalase molecules induced by irradiation have been fractionated. The results lead to the conclusion that aggregates are composed of active and modified catalase monomers. (author)

  10. Chemiluminescence measurements as an identification method for gamma-irradiated foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    Boegl, W; Heide, L

    1985-01-01

    Samples of 19 different spices, milk powder, whole onions and frozen chicken were exposed to a Co-60 source with radiation doses up to 10/sup 4/ Gy. The subsequent reaction of the irradiated foodstuffs in a luminol solution resulted in light emission (chemiluminescence). This effect can be used as an indicator of radiation treatment.

  11. Effect of γ-rays irradiation and alkali solution pretreatment on hydrolyzing enzyme and microcosmic structure of core straw

    International Nuclear Information System (INIS)

    Tang Hongtao; Wang Feng; Li Weiming; Li An; Ha Yiming; Li Yanjie

    2012-01-01

    To increase yield of reducing sugar enzymatic hydrolyzed from corn straw yield of corn stalk on Enzymatic hydrolysis, γ-rays radiation and NaOH solution pretreatment were used. The changes of microstructure of the corn straw before and after pretreatments were characterized by IR, X-rays diffraction and SEM. The results shows that the γ-rays radiation can significantly decrease the essential concentration of NaOH solution and shorten the immersion time, but it could not affected the yield of reducing sugar remarkably. The scanning electron microscopy (SEM) results show that the sample which was treated at the 200 kGy irradiation dose and NaOH solution circumstance has the biggest surface area increase. The reducing sugar content of enzyme hydrolyzed corn straw treated at 200 kGy irradiation dose and 2% NaOH solution was achieved 48.34%, which provides the theoretical basis for industry ethanol production using enzyme hydrolyzed corn straw. (authors)

  12. A fresh method of DNA transformation to the seeds irradiated by Co ...

    African Journals Online (AJOL)

    Jane

    2011-06-29

    Jun 29, 2011 ... To find out a simpler method that can directly transfer the aim gene into plant ... Key words: DNA transformation, irradiated seeds, purple medic, salt screening. ..... characterization of a maize mitochondrial plasmid-like DNA.

  13. Development of genetic methods for detection of pathogenic microorganisms in irradiated food

    International Nuclear Information System (INIS)

    2010-01-01

    The existence of injured microorganisms in food and their recovery during culturing procedures is critical. Injured microorganisms present a potential threat in food safety since they may repair themselves under suitable conditions. This study provides development of recovery methods for detection of injured foodborne microorganisms, after irradiation treatment at different doses. For this purpose, iniatially the methods of recovery were compared at different irradiation doses. At the second step, antibiotic resistance of foodborne pathogens was determined. After determination of antibiotic resistance, recovery methods were modified for reversibly injured foodborne pathogens at different doses after irradiation treatment . Finally, damages of DNA were detected by a spectrophotometric method after 1.0 kGy irradiation treatment

  14. Lower and Upper Solutions Method for Positive Solutions of Fractional Boundary Value Problems

    Directory of Open Access Journals (Sweden)

    R. Darzi

    2013-01-01

    Full Text Available We apply the lower and upper solutions method and fixed-point theorems to prove the existence of positive solution to fractional boundary value problem D0+αut+ft,ut=0, 0

  15. Effects of light irradiation on bleaching by a 3.5% hydrogen peroxide solution containing titanium dioxide

    International Nuclear Information System (INIS)

    Suemori, T; Kato, J; Nakazawa, T; Akashi, G; Igarashi, A; Hirai, Y; Kumagai, Y; Kurata, H

    2008-01-01

    A low-concentration hydrogen peroxide solution containing titanium dioxide as a photocatalyst has attracted attention as a safe office bleaching agent. In this study, the influence of different kinds of light on the bleaching effect of this agent was examined. The bleaching agent was applied to hematoporphyrin-stained paper strips that were then irradiated with a 405-nm diode laser (800 mW/cm 2 ), a halogen lamp (720 mW/cm 2 ), or an LED (835 mW/cm 2 ) for 5 minutes. The color was measured spectrophotometrically before treatment and every 30 seconds thereafter, and the effects of bleaching on the strip were assessed using the CIE 1976 L * a * b * color coordinate system. Of the three different irradiation conditions, 405-nm laser irradiation gave the strongest bleaching effect with 3.5% hydrogen peroxide containing titanium dioxide. The laser provides strong irradiance at 405 nm, which corresponds to the absorption range of the bleaching agent, and consequently the largest effect was obtained

  16. Protein aggregation in aqueous casein solution. Effect of irradiation, dose level, concentration, storage and additives (carbohydrate and lipid)

    Energy Technology Data Exchange (ETDEWEB)

    Yousri, R M

    1980-06-01

    From the vast amount of research efforts dealing with various aspects of radiation effects on foods and food components, it is apparent up to now that much remains to be studied in depth, much may have to be added or corrected about radiation-induced physico-chemical changes in foods. A great many reactions that take place when foodstuffs are subjected to ionizing radiation are still not fully understood. The better understanding of some of the radiation-induced changes in pure proteins as such or in mixture with other food constituents could yield much data which could be meaningfully extrapolated to intact foods and consequently could help to improve the assessment of the wholesomeness of irradiated foods. It was the purpose of our investigations to elucidate some of the changes in the chemical structure of a pure protein (casein), irradiated as such or with added carbohydrate and/or lipid. The effect of subsequent storage of the irradiated solutions has been also examined. The formation of protein aggregates was studied by gel filtration technique. The application of thin-layer gel filtration, its speed and adaptability to very small samples facilitated the measurements of the extent of aggregation which occurred in protein molecules after irradiation.

  17. Relative frequency of formation of base radioproduct, single and double strand breaks on irradiation of diluted aqueous solution of DNA

    International Nuclear Information System (INIS)

    Ryznar, L.; Drasil, V.

    1975-01-01

    Diluted aqueous solution of DNA labelled with 6- 3 H-TdR was irradiated in the absence of oxygen and numbers of formed single and double strand breaks and the 5,6-dihydrothymine (DHT) yield were determined. The results indicate that, under given conditions, a molecule of a base radioproduct is formed approximately 10 times more frequently than one single strand break. The occurence of a single strand break is 20 times higher than that of a double strand break. The DNA labelled with 6- 3 H-TdR was isolated from mice fibroblasts of L-strain according to Marmur (specific activity 3.0 MBq/82 μCi/mg DNA, molecular weight M/sub n/=9.32x10 6 dalton). Solution of DNA was irradiated in the absence of oxygen (180 Gy /1.8x10 4 rads/, absorbed dose rate 0.3 Gy/s). It was lyophilized with an addition of non-labelled thymine, thymidine and DHT and then hydrolysed with 90% formic acid. The dried hydrolysate was chromatographed with irradiated non-labelled thymine added as a carrier. (F.G.)

  18. Kinetic modeling and simulation of PCE and TCE removal in aqueous solutions by electron-beam irradiation

    International Nuclear Information System (INIS)

    Nickelsen, Michael G.; Cooper, William J.; Secker, David A.; Rosocha, Louis A.; Kurucz, Charles N.; Waite, Thomas D.

    2002-01-01

    The irradiation of aqueous solutions of TCE and PCE using a high-energy electron-beam results in the rapid decomposition of both chemicals. It is known that both TCE and PCE react with the aqueous electron and the hydroxyl radical with bimolecular rate constants greater than 10 9 M -1 s -1 for each reaction. The fact that high-energy electrons produce significant concentrations of both e aq - and ·OH radicals in water makes it an effective process for the removal of TCE and PCE from aqueous solution. We have employed steady state and computer-based chemical kinetic models to simulate and better understand the chemistry and kinetics of e-beam irradiation when applied to natural water systems. Model results were benchmarked to experimental data, allowing for the optimization of the reaction of DOC with the ·OH radical. Values for the associated second-order reaction rate constant were found to be 2.5x10 8 and 4.0x10 8 M -1 s -1 , consistent with reported values for k OH,DOC . The models were also used to investigate the possibility of incomplete irradiation during treatment and the presence of proposed chemical reactions of by-products. The reactions involve radicals and radical-adduct species formed by the reaction of TCE and PCE with the hydroxyl radical

  19. New exact solutions of the (2 + 1)-dimensional breaking soliton system via an extended mapping method

    International Nuclear Information System (INIS)

    Ma Songhua; Fang Jianping; Zheng Chunlong

    2009-01-01

    By means of an extended mapping method and a variable separation method, a series of solitary wave solutions, periodic wave solutions and variable separation solutions to the (2 + 1)-dimensional breaking soliton system is derived.

  20. An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    2004-01-01

    Analytical Method of Auxiliary Sources solutions for plane wave scattering by circular impedance cylinders are derived by transformation of the exact eigenfunction series solutions employing the Hankel function wave transformation. The analytical Method of Auxiliary Sources solution thus obtained...

  1. Enlargement of induced variations by combined method of chronic irradiations with callus culture in sugarcane

    International Nuclear Information System (INIS)

    Nagatomi, Shigeki

    1993-01-01

    The present study was conducted to elucidate the effects of gamma ray irradiation and callus culture upon induced variation of the regeneratives. The populations regenerated from young leaf tissue of chronic irradiated plnats grown under a gamma field receiving a total dose of 300 and 100 Gy, showed rather wider variation on quantitative characters than plants from populations of the non-irradiated. This variation extended in both negative and positive directions. Analysis of variance also revealed that variation and heritability in broad sense of most agronomic characters increased significantly among the subclones as the irradiation done rose. Principal component analysis also indicated that the subclones from the irradiated population were more variable than the non-irradiated. Such variation with higher heritability could be transmitted to the following generations by clonal propagation and utilized as genetic sources in mutation breeding. The combined method with chronic irradiation followed by tissue culture is evaluated as an effective method of widening mutation spectrum and increasing mutation frequency in regenerated plants. In addition, this method is valid to improve any crop species which can regenerate plants through callus culture. (author)

  2. Studies on Microbiological and Biological Methods for Detection of Irradiated Food

    International Nuclear Information System (INIS)

    Ibrahim, H.M.A.

    2013-01-01

    The main aim of this study is to evaluate a microbiological and biological methods used for the detection of irradiated foods in Egypt. The microbiological methods included were shift in microflora load and direct epifluroescent filter technique compared with aerobic plate count (DEFT/APC), while the biological method was DNA comet assay. The selected foods were black, strawberry, fresh-and frozen-de boned chicken. The samples of these foods were exposed to different doses of gamma radiation according to the purpose of irradiation for each food. The results indicated that the characteristics of microbial population of all irradiated samples have been changed. The very lower count of viable bacterial count (APC) and mold and yeasts counts in the samples than the reported normal count as well as the absence of Gram- negative bacteria and Enterobacteriaceae group from these samples could be used as an indication for radiation treatment of these foods. The large difference between microbial counts obtained by DEFT test and that obtained by APC test could also be used for screening radiation treatment of these foods. Photographic and image analysis of DNA comet assay showed that irradiation of these foods caused damage to the food cells DNA (fragmentation) at different levels according to the doses used and kind of foods. This DNA damage can be followed or described by DNA comet assay test. On the basis of comet assay, the discrimination between unirradiated and irradiated food samples was very possible. In general the results showed that DEFT/APC method had the potential to detect irradiated food samples either at zero time of storage or throughout the storage period post- irradiation. DNA comet assay as a rapid, simple and inexpensive screening test approved to be successful for detection of irradiated food samples under investigation. Determination of rough applied irradiation dose is possible if photographic analysis is combined with image analysis

  3. Identification of irradiated pasteurized egg products: a combined method to use in routine control

    International Nuclear Information System (INIS)

    Helle, N.; Schulzki, G.; Linke, B.; Spiegelberg, A.; Boegl, K.W.; Schreiber, G.A.; Grabowski, H.U. v.; Pfordt, J.; Mauermann, U.; Juelicher, S.; Bischoff, C.; Vater, N.; Heitmann, M.

    1993-01-01

    Pasteurized egg products (whole egg, egg yolk and egg white) were tested for irradiation treatment in the German food control laboratories in Oldenburg/Niedersachsen and Kassel/Hessen as well as in the food irradiation laboratory of the German federal health office. Gas chromatographic/mass spectrometric measurements on the fat components of egg-products showed clearly whether the product had been irradiated or not. While in unirradiated samples no traces of special hydrocarbons (according to the fatty acid composition of egg) and no traces of the irradiation-specific compound 2-Dodecyl-cyclobutanone were found, irradiated control samples as well as products of two belgian suppliers contained these substances. Additionally, regarding the rather high time consumption of gas chromatography, electron spin resonance (ESR)-measurements were carried out on the packaging material of egg products. Irradiated packaging material (cellulose) could be easily detected by the appearance of a signal pair in the ESR spectrum (cellulose radical). ESR measurements are very fast and easy to perform so that this method can be used for screening. Microbiological investigations showed remarkably reduced total numbers of microorganisms for some irradiated samples, but the microbiological status is influenced by other factors like storage-time and -temperature, so that microbiological tests can not be used successfully for screening on irradiation treatment [de

  4. Identification of irradiated spices by the use of thermoluminescence method (TL)

    Energy Technology Data Exchange (ETDEWEB)

    Sharifzadeh, M.; Sohrabpour, M. (Atomic Energy Organization of Iran, Teheran (Iran, Islamic Republic of))

    In this paper the results of the investigation of identification of irradiated spices by the use of thermoluminescence method is reported. The materials used were black and red peppers, turmeric, cinnamon, and garlic powder. Gamma Cell 220 was used for irradiating samples at dose values of 2.5, 5, 7.5 and 10 kGy respectively. The TL intensity of the unirradiated spices as well as the fading characteristics of the irradiated samples having received a dose of 10 kGy have been measured. Post-irradiation temperature treatment of the irradiated (10 kGy) and unirradiated samples at 60[sup o]C and 100[sup o]C for 24 hours have also been performed. The results show that the TL intensities of unirradiated and irradiated samples from different batches of each spice are fairly distributed. A reasonable TL intensity versus dose has been observed in nearly all cases. Based on the observation made it is possible to distinguish irradiated spices after (4-9) months post-irradiation. (author).

  5. Identification of irradiated spices by the use of thermoluminescence method (TL)

    International Nuclear Information System (INIS)

    Sharifzadeh, M.; Sohrabpour, M.

    1993-01-01

    In this paper the results of the investigation of identification of irradiated spices by the use of thermoluminescence method is reported. The materials used were black and red peppers, turmeric, cinnamon, and garlic powder. Gamma Cell 220 was used for irradiating samples at dose values of 2.5, 5, 7.5 and 10 kGy respectively. The TL intensity of the unirradiated spices as well as the fading characteristics of the irradiated samples having received a dose of 10 kGy have been measured. Post-irradiation temperature treatment of the irradiated (10 kGy) and unirradiated samples at 60 o C and 100 o C for 24 hours have also been performed. The results show that the TL intensities of unirradiated and irradiated samples from different batches of each spice are fairly distributed. A reasonable TL intensity versus dose has been observed in nearly all cases. Based on the observation made it is possible to distinguish irradiated spices after (4-9) months post-irradiation. (author)

  6. Higher order methods for burnup calculations with Bateman solutions

    International Nuclear Information System (INIS)

    Isotalo, A.E.; Aarnio, P.A.

    2011-01-01

    Highlights: → Average microscopic reaction rates need to be estimated at each step. → Traditional predictor-corrector methods use zeroth and first order predictions. → Increasing predictor order greatly improves results. → Increasing corrector order does not improve results. - Abstract: A group of methods for burnup calculations solves the changes in material compositions by evaluating an explicit solution to the Bateman equations with constant microscopic reaction rates. This requires predicting representative averages for the one-group cross-sections and flux during each step, which is usually done using zeroth and first order predictions for their time development in a predictor-corrector calculation. In this paper we present the results of using linear, rather than constant, extrapolation on the predictor and quadratic, rather than linear, interpolation on the corrector. Both of these are done by using data from the previous step, and thus do not affect the stepwise running time. The methods were tested by implementing them into the reactor physics code Serpent and comparing the results from four test cases to accurate reference results obtained with very short steps. Linear extrapolation greatly improved results for thermal spectra and should be preferred over the constant one currently used in all Bateman solution based burnup calculations. The effects of using quadratic interpolation on the corrector were, on the other hand, predominantly negative, although not enough so to conclusively decide between the linear and quadratic variants.

  7. Properties of gases, liquids, and solutions principles and methods

    CERN Document Server

    Mason, Warren P

    2013-01-01

    Physical Acoustics: Principles and Methods, Volume ll-Part A: Properties of Gases, Liquids, and Solutions ponders on high frequency sound waves in gases, liquids, and solids that have been proven as effective tools in examining the molecular, domain wall, and other types of motions. The selection first offers information on the transmission of sound waves in gases at very low pressures and the phenomenological theory of the relaxation phenomena in gases. Topics include free molecule propagation, phenomenological thermodynamics of irreversible processes, and simultaneous multiple relaxation pro

  8. Methods for removing transuranic elements from waste solutions

    International Nuclear Information System (INIS)

    Slater, S.A.; Chamberlain, D.B.; Connor, C.; Sedlet, J.; Srinivasan, B.; Vandegrift, G.F.

    1994-11-01

    This report outlines a treatment scheme for separating and concentrating the transuranic (TRU) elements present in aqueous waste solutions stored at Argonne National Laboratory (ANL). The treatment method selected is carrier precipitation. Potential carriers will be evaluated in future laboratory work, beginning with ferric hydroxide and magnetite. The process will result in a supernatant with alpha activity low enough that it can be treated in the existing evaporator/concentrator at ANL. The separated TRU waste will be packaged for shipment to the Waste Isolation Pilot Plant

  9. Method to obtain molybdenum 99 from a matrix containing neutron-irradiated, fissionable materials and fission products

    International Nuclear Information System (INIS)

    Ali, S.A.H.; Knapp, J.; Reinhardt, J.

    1977-01-01

    A method to obtain a highly pure Mo 99 compound is suggested which is easy to perform even with remote handling. The matrix irradiated by neutrons is rendered soluble with aqueous alkali hydroxide solution, the Mo 99 being dissolved. The Mo rhodanide complex is collected on an organic ion exchanger. The individual process steps are described. A suitable iodine reducing agent (e.g. Na or Ka sulphite, hydroxyl ammonium sulphate) is already added to the first step and to the washing of the ion exchanger. Where necessary Tc 99 is eluated from the fixed Mo 99 mother nuclide for use in nuclear medicine. (UWI) [de

  10. Method for analyzing passive silicon carbide thermometry with a continuous dilatometer to determine irradiation temperature

    Science.gov (United States)

    Campbell, Anne A.; Porter, Wallace D.; Katoh, Yutai; Snead, Lance L.

    2016-03-01

    Silicon carbide is used as a passive post-irradiation temperature monitor because the irradiation defects will anneal out above the irradiation temperature. The irradiation temperature is determined by measuring a property change after isochronal annealing, i.e., lattice spacing, dimensions, electrical resistivity, thermal diffusivity, or bulk density. However, such methods are time-consuming since the steps involved must be performed in a serial manner. This work presents the use of thermal expansion from continuous dilatometry to calculate the SiC irradiation temperature, which is an automated process requiring minimal setup time. Analysis software was written that performs the calculations to obtain the irradiation temperature and removes possible user-introduced error while standardizing the analysis. This method has been compared to an electrical resistivity and isochronal annealing investigation, and the results revealed agreement of the calculated temperatures. These results show that dilatometry is a reliable and less time-intensive process for determining irradiation temperature from passive SiC thermometry.

  11. A new criterion of photostimulated luminescence (PSL) method to detect irradiated traditional Chinese medicinal herbs

    International Nuclear Information System (INIS)

    Zhang, Liwen; Lin, Tong; Jiang, Yingqiao; Bi, Fujun

    2013-01-01

    This work used a new criterion to analyze 162 varieties (222 batches) of traditional Chinese medicinal herbs based on the European Standard EN 13751 (2009. Foodstuffs—Detection of Irradiated Food Using Photostimulated Luminescence. European Committee for Standardization, Brussels, Belgium). The characteristics of PSL signals are described, and a new criterion is established. Compared to EN 13751, the new criterion uses clearer definition to evaluate instead of the ambiguous descriptions in EN Standard, such as “much greater than” and “within the same order of magnitude”. Moreover, the accuracy of the new criterion is as good as or better than EN Standard in regard to classifying irradiated and non-irradiated traditional Chinese medicinal herbs. It can help to avoid false positive result when a non-irradiated herb got a screening PSL measurement above 5000 counts/60 s. This new criterion of photostimulated luminescence method can be applied to identify the irradiation status of traditional Chinese medicinal herbs, even if the medicinal herbs were irradiated at a low dose (0.3 kGy) or stored in the dark at room temperature for 24 months after the irradiation treatment. - Highlights: • Clearer evaluation criterion instead of the ambiguous descriptions in EN 13751. • Accuracy satisfied. • Large sample size provides outstanding representativeness. • Systematical evaluation on PSL method

  12. Uniform irradiation system using beam scanning method for cyclotron

    International Nuclear Information System (INIS)

    Agematsu, Takashi; Okumura, Susumu; Arakawa, Kazuo

    1994-03-01

    JAERI AVF-cyclotron is equipped with an ion beam scanner for large area irradiation. The two-dimensional fluence distribution of ion beam obtained using cellulose triacetate film dosimeter was not uniform. This is resulted from the distortion of excitation current for electromagnet of the scanner. So, the beam scanning condition, i.e., the relation between the ion species, the beam profile and the scanning width, was extremely limited to make a good uniformity. We have developed a beam scanning simulator to get fluence distributions by calculation and then compared the simulated distributions with the measured ones. It was revealed that the both of them are in good agreement and the beam scanning condition to get good uniformity was led by using this simulator. On the basis of these results, the power supply of scanner was improved. A good uniformity of beam distribution was available. (author)

  13. Emission control of SO2 and NOx by irradiation methods

    International Nuclear Information System (INIS)

    Radoiu, Marilena T.; Martin, Diana I.; Calinescu, Ioan

    2003-01-01

    Microwave discharges at 2.45 GHz frequency and accelerated electron beams operated at atmospheric pressure in synthetic gas mixtures containing N 2 , O 2 , CO 2 , SO 2 , and NO x are investigated experimentally for various gas mixture constituents and operating conditions, with respect to their ability to purify exhaust gases. An original experimental unit easily adaptable for both separate and simultaneous irradiation with microwaves and electron beams was set up. The simultaneous treatment with accelerated electron beams and microwaves was found to increase the removal efficiency of NO x and SO 2 and also helped to reduce the total required dose rate with ∼30%. Concomitant removal of NO x (∼80%) and SO 2 (>95%) by precipitation with ammonia was achieved

  14. A reliable method for reconstituting thymectomized, lethally irradiated guinea pigs with bone marrow cells

    International Nuclear Information System (INIS)

    Terata, N.; Tanio, Y.; Zbar, B.

    1984-01-01

    The authors developed a reliable method for reconstituting thymectomized, lethally irradiated guinea pigs. Injection of 2.5-10 x 10 7 syngeneic bone marrow cells into adult thymectomized, lethally irradiated guinea pigs produced survival of 46-100% of treated animals. Gentamycin sulfate (5 mg/kg of body weight) for 10 days was required for optimal results. Acidified drinking water (pH 2.5) appeared to be required for optimal results. Thymectomized, lethally irradiated, bone marrow reconstituted ('B') guinea pigs had impaired ability to develop delayed cutaneous hypersensitivity to mycobacterial antigens and cutaneous basophil hypersensitivity to keyhole limpet hemocyanin; proliferative responses to phytohemagglutinin were impaired. (Auth.)

  15. Application of a rapid screening method to detect irradiated meat in Brazil

    International Nuclear Information System (INIS)

    Villavicencio, A.L.C.H.; Mancini-Filho, J.; Delincee, H.

    2000-01-01

    Based on the enormous potential for food irradiation in Brazil, and to ensure free consumer choice, there is a need to find a convenient and rapid method for detection of irradiated food. Since treatment with ionising radiation causes DNA fragmentation, the analysis of DNA damage might be promising. In this paper, the DNA Comet Assay was used to identify exotic meat (boar, jacare and capybara), irradiated with 60 Co gamma rays. The applied radiation doses were 0, 1.5, 3.0 and 4.5 kGy. Analysis of the DNA migration enabled a rapid identification of the radiation treatment

  16. Comparsion of maximum viscosity and viscometric method for identification of irradiated sweet potato starch

    International Nuclear Information System (INIS)

    Yi, Sang Duk; Yang, Jae Seung

    2000-01-01

    A study was carried out to compare viscosity and maximum viscosity methods for the detection of irradiated sweet potato starch. The viscosity of all samples decreased by increasing stirring speeds and irradiation doses. This trend was similar for maximum viscosity. Regression coefficients and expressions of viscosity and maximum viscosity with increasing irradiation dose were 0.9823 (y=335.02e -0. 3 366x ) at 120 rpm and 0.9939 (y =-42.544x+730.26). This trend in viscosity was similar for all stirring speeds. Parameter A, B and C values showed a dose dependent relation and were a better parameter for detecting irradiation treatment than maximum viscosity and the viscosity value it self. These results suggest that the detection of irradiated sweet potato starch is possible by both the viscometric and maximum visosity method. Therefore, the authors think that the maximum viscosity method can be proposed as one of the new methods to detect the irradiation treatment for sweet potato starch

  17. Monte Carlo methods for flux expansion solutions of transport problems

    International Nuclear Information System (INIS)

    Spanier, J.

    1999-01-01

    Adaptive Monte Carlo methods, based on the use of either correlated sampling or importance sampling, to obtain global solutions to certain transport problems have recently been described. The resulting learning algorithms are capable of achieving geometric convergence when applied to the estimation of a finite number of coefficients in a flux expansion representation of the global solution. However, because of the nonphysical nature of the random walk simulations needed to perform importance sampling, conventional transport estimators and source sampling techniques require modification to be used successfully in conjunction with such flux expansion methods. It is shown how these problems can be overcome. First, the traditional path length estimators in wide use in particle transport simulations are generalized to include rather general detector functions (which, in this application, are the individual basis functions chosen for the flus expansion). Second, it is shown how to sample from the signed probabilities that arise as source density functions in these applications, without destroying the zero variance property needed to ensure geometric convergence to zero error

  18. A generalized trial solution method for solving the aerosol equation

    International Nuclear Information System (INIS)

    Simons, S.; Simpson, D.R.

    1988-01-01

    It is shown how the introduction of orthogonal functions together with a time-dependent scaling factor may be used to develop a generalized trial solution method for tackling the aerosol equation. The approach is worked out in detail for the case where the initial particle size spectrum follows a γ-distribution, and it is shown to be a viable technique as long as the initial volume fraction of particulate material is not too large. The method is applied to several situations of interest, and is shown to give more accurate results (with marginally shorter computing times) than are given by the three-parameter log-normal or γ distribution trial functions. (author)

  19. A finite element solution method for quadrics parallel computer

    International Nuclear Information System (INIS)

    Zucchini, A.

    1996-08-01

    A distributed preconditioned conjugate gradient method for finite element analysis has been developed and implemented on a parallel SIMD Quadrics computer. The main characteristic of the method is that it does not require any actual assembling of all element equations in a global system. The physical domain of the problem is partitioned in cells of n p finite elements and each cell element is assigned to a different node of an n p -processors machine. Element stiffness matrices are stored in the data memory of the assigned processing node and the solution process is completely executed in parallel at element level. Inter-element and therefore inter-processor communications are required once per iteration to perform local sums of vector quantities between neighbouring elements. A prototype implementation has been tested on an 8-nodes Quadrics machine in a simple 2D benchmark problem

  20. Enhanced photocatalytic performance of BiVO_4 in aqueous AgNO_3 solution under visible light irradiation

    International Nuclear Information System (INIS)

    Huang, Chien-Kai; Wu, Tsunghsueh; Huang, Chang-Wei; Lai, Chi-Yung; Wu, Mei-Yao; Lin, Yang-Wei

    2017-01-01

    Graphical abstract: Ag"+ ions enhanced photocatalytic activity of BiVO_4 under visible light irradiation. - Highlights: • The presence of Ag"+ ions enhanced the photodegradation activity of BiVO_4. • Photoreduction of Ag deposited on the BiVO_4 surface was obtained. • Luminescence and electrochemical results elucidated the photocatalytic mechanism. • Holes and oxygen radicals were the main reactive species generated by BiVO_4/Ag"+. • Used BiVO_4/Ag"+ exhibited photocatalytic antibacterial activity toward E. coli. - Abstract: Monoclinic-phase bismuth vanadate (BiVO_4) with a 2.468 eV band gap exhibited enhanced synergic photodegradation activity toward methylene blue (MB) when combined with silver ions (Ag"+) in an aqueous solution under visible light irradiation. The mass ratio of AgNO_3 to BiVO_4 and the calcination temperature were discovered to considerably affect the degradation activity of BiVO_4/Ag"+. Superior photocatalytic performance was obtained when BiVO_4 was mixed with 0.01%(w/v) AgNO_3 solution, and complete degradation of MB was achieved after 25 min visible light irradiation, outperforming BiVO_4 or AgNO_3 solution alone. The enhanced photodegradation was investigated using systematic luminescence measurements, electrochemical impedance spectroscopy, and scavenger addition, after which a photocatalytic mechanism for MB degradation under visible light irradiation was identified that involved oxygen radicals and holes. This study also discovered the two dominating processes involved in enhancing the electron–hole separation efficiency and reducing their recombination rate, namely photoreduction of Ag"+ and the formation of a BiVO_4/Ag heterojunction. The synergic effect between BiVO_4 and Ag"+ was discovered to be unique. BiVO_4/Ag"+ was successfully used to degrade two other dyes and disinfect Escherichia Coli. A unique fluorescent technique using BiVO_4 and a R6G solution to detect Ag"+ ions in water was discovered.

  1. Improvement of mechanical properties of hydrogel by irradiation of polymers in aqueous solution with κ-carrageenan

    International Nuclear Information System (INIS)

    Makuuchi, K.; Yoshii, F.; Zhai, M.

    2000-01-01

    Predominate radiation reaction of κ-carrageenan (KC) hydrogel is the main chain scission of KC. The gel strength of KC hydrogel decreased with increasing irradiation dose. However, KC was found to enhances the radiation crosslinking of synthetic water-soluble polymer (SWSP) such as poly(ethylene oxide) (PEO) and poly(N-vinylpyrolidone) (PVP) in aqueous solution. The gel strength of SWSP hydrogel increased with increasing dose when KC was blended. Probably the radiation degraded KC radicals are recombined with radicals of PVP and PEO. The hydrogel thus prepared absorbs huge amounts of water due to the presence of strong hydrophilic -OSO 3 - groups in KC. (author)

  2. Improvement of mechanical properties of hydrogel by irradiation of polymers in aqueous solution with {kappa}-carrageenan

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, K.; Yoshii, F. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Aranilla, C.T. [Philippine Nuclear Research Institute, Diliman, Quezon (Philippines); Zhai, M. [Department of Technical Physics, Peking Univ., Beijing (China)

    2000-03-01

    Predominate radiation reaction of {kappa}-carrageenan (KC) hydrogel is the main chain scission of KC. The gel strength of KC hydrogel decreased with increasing irradiation dose. However, KC was found to enhances the radiation crosslinking of synthetic water-soluble polymer (SWSP) such as poly(ethylene oxide) (PEO) and poly(N-vinylpyrolidone) (PVP) in aqueous solution. The gel strength of SWSP hydrogel increased with increasing dose when KC was blended. Probably the radiation degraded KC radicals are recombined with radicals of PVP and PEO. The hydrogel thus prepared absorbs huge amounts of water due to the presence of strong hydrophilic -OSO{sub 3}{sup -} groups in KC. (author)

  3. The method of lines solution of discrete ordinates method for non-grey media

    International Nuclear Information System (INIS)

    Cayan, Fatma Nihan; Selcuk, Nevin

    2007-01-01

    A radiation code based on method of lines (MOL) solution of discrete ordinates method (DOM) for radiative heat transfer in non-grey absorbing-emitting media was developed by incorporation of a gas spectral radiative property model, namely wide band correlated-k (WBCK) model, which is compatible with MOL solution of DOM. Predictive accuracy of the code was evaluated by applying it to 1-D parallel plate and 2-D axisymmetric cylindrical enclosure problems containing absorbing-emitting medium and benchmarking its predictions against line-by-line solutions available in the literature. Comparisons reveal that MOL solution of DOM with WBCK model produces accurate results for radiative heat fluxes and source terms and can be used with confidence in conjunction with computational fluid dynamics codes based on the same approach

  4. A method of analyzing rectal surface area irradiated and rectal complications in prostate conformal radiotherapy

    International Nuclear Information System (INIS)

    Lu Yong; Song, Paul Y.; Li Shidong; Spelbring, Danny R.; Vijayakumar, Srinivasan; Haraf, Daniel J.; Chen, George T.Y.

    1995-01-01

    Purpose: To develop a method of analyzing rectal surface area irradiated and rectal complications in prostate conformal radiotherapy. Methods and Materials: Dose-surface histograms of the rectum, which state the rectal surface area irradiated to any given dose, were calculated for a group of 27 patients treated with a four-field box technique to a total (tumor minimum) dose ranging from 68 to 70 Gy. Occurrences of rectal toxicities as defined by the Radiation Therapy Oncology Group (RTOG) were recorded and examined in terms of dose and rectal surface area irradiated. For a specified end point of rectal complication, the complication probability was analyzed as a function of dose irradiated to a fixed rectal area, and as a function of area receiving a fixed dose. Lyman's model of normal tissue complication probability (NTCP) was used to fit the data. Results: The observed occurrences of rectal complications appear to depend on the rectal surface area irradiated to a given dose level. The patient distribution of each toxicity grade exhibits a maximum as a function of percentage surface area irradiated, and the maximum moves to higher values of percentage surface area as the toxicity grade increases. The dependence of the NTCP for the specified end point on dose and percentage surface area irradiated was fitted to Lyman's NTCP model with a set of parameters. The curvature of the NTCP as a function of the surface area suggests that the rectum is a parallel structured organ. Conclusions: The described method of analyzing rectal surface area irradiated yields interesting insight into understanding rectal complications in prostate conformal radiotherapy. Application of the method to a larger patient data set has the potential to facilitate the construction of a full dose-surface-complication relationship, which would be most useful in guiding clinical practice

  5. Study on application of the physical detection methods for electron beam-irradiated agricultural products

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Yong; Park, Yong Dae; Jin, Chang Hyun; Choi, Dae Seong; Jeong, Il Yun [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Yook, Hong Sun [Chungnam National University, Daejeon (Korea, Republic of)

    2010-09-15

    Physical detection methods, photostimulated luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR) were applied to detect electron beam-irradiated agricultural products, such as red pepper, black pepper, raisin, walnut, beef seasoning and pistachio. The absorbed irradiation doses for representative samples were controlled at 0, 1, 3, 5 and 10 kGy. PSL values for non-irradiated samples were <700 counts/60s (lower threshold, T{sub 1}) except beef seasoning, whereas those of irradiated samples were more than 5,000 photon counts, upper threshold (T{sub 2}) in black pepper, raisin, and beef seasoning and intermediates values of T{sub 1}-T{sub 2} in red pepper, walnut, and pistachio. Minerals separated from the samples for TL measurement showed that non-irradiated samples except pistachio (TL ratio, 0.12) were characterized by no glow curves situated at temperature range of 50 {approx} 400 .deg. C with TL ratio (0.01 {approx} 0.08), while irradiated samples except pistachio at only 1 kGy (TL ratio, 0.08) indicated glow curve at about 150 {approx} 250 .deg. C with TL ratio (0.28 {approx} 3.10). ESR measurements of irradiated samples any specific signals to irradiation. The samples of both red pepper ad pistachio were produced specific signals derived from cellulose radicals as well as single line signals for black pepper and walnut, and multiple signals derived from crystalline sugar radicals for raisin and beef seasoning. In conclusion, The ESR methods can apply for detection of pistachio exposed to electron beam but PSL and TL are not suitable methods. Furthermore, TL and ESR suggested that both techniques were more useful detection method than PSL to confirm whether red pepper, walnut and beef seasoning samples have been exposed to electron beam.

  6. Study on application of the physical detection methods for electron beam-irradiated agricultural products

    International Nuclear Information System (INIS)

    Kim, Dong Yong; Park, Yong Dae; Jin, Chang Hyun; Choi, Dae Seong; Jeong, Il Yun; Yook, Hong Sun

    2010-01-01

    Physical detection methods, photostimulated luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR) were applied to detect electron beam-irradiated agricultural products, such as red pepper, black pepper, raisin, walnut, beef seasoning and pistachio. The absorbed irradiation doses for representative samples were controlled at 0, 1, 3, 5 and 10 kGy. PSL values for non-irradiated samples were 1 ) except beef seasoning, whereas those of irradiated samples were more than 5,000 photon counts, upper threshold (T 2 ) in black pepper, raisin, and beef seasoning and intermediates values of T 1 -T 2 in red pepper, walnut, and pistachio. Minerals separated from the samples for TL measurement showed that non-irradiated samples except pistachio (TL ratio, 0.12) were characterized by no glow curves situated at temperature range of 50 ∼ 400 .deg. C with TL ratio (0.01 ∼ 0.08), while irradiated samples except pistachio at only 1 kGy (TL ratio, 0.08) indicated glow curve at about 150 ∼ 250 .deg. C with TL ratio (0.28 ∼ 3.10). ESR measurements of irradiated samples any specific signals to irradiation. The samples of both red pepper ad pistachio were produced specific signals derived from cellulose radicals as well as single line signals for black pepper and walnut, and multiple signals derived from crystalline sugar radicals for raisin and beef seasoning. In conclusion, The ESR methods can apply for detection of pistachio exposed to electron beam but PSL and TL are not suitable methods. Furthermore, TL and ESR suggested that both techniques were more useful detection method than PSL to confirm whether red pepper, walnut and beef seasoning samples have been exposed to electron beam

  7. Preparation of poly(vinylbenzyl chloride)-grafted PFA film by a simultaneous irradiation grafting method

    International Nuclear Information System (INIS)

    Fei, Geng; Shin, Jun Hwa; Nho, Young Chang; Lee, Youn Sik

    2009-01-01

    In this study, PFA-g-PVBC films were prepared by a radiation grafting of vinylbenzyl chloride (VBC) monomer onto poly(tetrafluoroethylene-co-perfluoro propyl vinyl ether) (PFA) films by simultaneous irradiation method. IR, TGA, and SEM-EDX instruments were utilized to confirm the successful preparation of the grafted film. The effects of several irradiation conditions, including the dose, VBC concentration, and film thickness on the degree of grafting of PFA-g-PVBC film were investigated

  8. Dosage of fission products in irradiated fuel treatment effluents (radio-chemical method); Dosage des produits de fission dans les effluents du traitement des combustibles irradies (methode radiochimique)

    Energy Technology Data Exchange (ETDEWEB)

    Auchapt, J [Commissariat a l' Energie Atomique, Marcoule (France). Centre d' Etudes Nucleaires

    1966-07-01

    The dosage methods presented here are applicable to relatively long-lived fission products present in the effluents resulting from irradiated fuel treatment processes (Sr - Cs - Ce - Zr - Nb - Ru - I). The methods are based on the same principle: - addition of a carrying-over agent - chemical separation over several purification stages, - determination of the chemical yield by calorimetry - counting of an aliquot liquid portion. (author) [French] Les methodes de dosage presentees concernent les produits de fission a vie relativement longue presents dans les effluents de traitement des combustibles irradies (Sr - Cs - Ce - Zr - Nb - Ru - I). Elles sont toutes basees sur le meme principe: - addition d'entraineur, - separation chimique en plusieurs stades de purification, - determination du rendement chimique par calorimetrie, - comptage d'une aliquote liquide. (auteur)

  9. Detection method of prawn irradiated in frozen state using tyrosine isomers as a marker

    International Nuclear Information System (INIS)

    Oikawa, H.; Satomi, M.; Omura, Y.; Yano, Y.

    2001-01-01

    Internationally the use of food irradiation has been expanding. And therefore a method is needed to detect whether food has been irradiated or not. We examined the content of the tyrosine isomers, m-tyrosine and omicron-tyrosine, of prawns irradiated in the frozen state (< -30 deg C) as a marker of the detection method. The tyrosine isomer content linearly increased with increasing dose, and the level of tyrosine isomers in the frozen-irradiated prawn was 50 - 60 % of the un frozen ones. But the difference in the content of tyrosine isomers between non-irradiated and irradiated at 5.0 kGy, that is the approved dose for frozen shellfish in countries where this technique is approved, is enough for discrimination. In addition, the content of tyrosine isomers showed little change during the frozen storage for 120 days. So we think the method using tyrosine isomers is suitable for practical use in Japan for imports of many kinds of frozen shellfish

  10. Food irradiation

    International Nuclear Information System (INIS)

    Beishon, J.

    1991-01-01

    Food irradiation has been the subject of concern and controversy for many years. The advantages of food irradiation include the reduction or elimination of dangerous bacterial organisms, the control of pests and insects which destroy certain foods, the extension of the shelf-life of many products, for example fruit, and its ability to treat products such as seafood which may be eaten raw. It can also replace existing methods of treatment which are believed to have hazardous side-effects. However, after examining the evidence produced by the proponents of food irradiation, the author questions whether it has any major contribution to make to the problems of foodborne diseases or world food shortages. More acceptable solutions, he suggests, may be found in educating food handlers to ensure that hygienic conditions prevail in the production, storage and serving of food. (author)

  11. Effect of molecular weight on radiation chemical degradation yield of chain scission of γ-irradiated chitosan in solid state and in aqueous solution

    International Nuclear Information System (INIS)

    Tahtat, Djamel; Mahlous, Mohamed; Benamer, Samah; Nacer Khodja, Assia; Larbi Youcef, Souad

    2012-01-01

    Chitosan A 1 , A 2 and A 3 with molecular weight of 471, 207 and 100 kDa respectively, produced from squid pen chitin was degraded by gamma rays in the solid state and in aqueous solution with various doses in air at ambient temperature. Effect of molecular weight on radiation chemical degradation yield of chain scission and degradation rate constants of γ-irradiated chitosan in solid state and in aqueous solution was investigated. The radiation chemical degradation yield G (s) and degradation rate values were calculated. The molecular weight changes were monitored by capillary viscometry method and the chemical structure changes were followed by UV analysis. The results showed that, the degradation of chitosan was faster in solution, than in solid state. The values of G (s) in solid state and in aqueous solution were respectively 1.1×10 −8 mol/J and 0.074×10 −7 mol/J for A 1 , 4.42×10 −8 mol/J and 0.28×10 −7 mol/J for A 2 and 6.08×10 −8 mol/J and 0.38×10 −7 mol/J for A 3 . Degradation rate constants values ranged from 0.41×10 −5 to 2.1×10 −5 kGy −1 in solid state, whereas in solution they ranged from 13×10 −5 to 68×10 −5 kGy −1 . The chitosan A 3 was more sensitive to radiolysis than A 1 and A 2 . The chain scission yield, G (s) and degradation rate constants seems to be greatly influenced by the initial molecular weight of the chitosan. Structural changes in irradiated chitosan are revealed by the apparition of absorption peaks at 261 and 295 nm, which could be attributed to the formation of carbonyl groups. In both conditions the peak intensity was higher in chitosan A 3 than in A 1 and A 2 , the oxidative products decreased with increasing molecular weight of chitosan. - Highlights: ► We investigated the effects of MW on G (s) value of γ-irradiated chitosan in solid and aqueous state. ► Chitosan with low molecular weight was more sensitive to radiolysis than high molecular weight. ► G (s) value and degradation rate

  12. Economical feasibility of irradiation method for the preservation of onions and potatoes in Libya

    International Nuclear Information System (INIS)

    Sharif, M.M.

    1990-01-01

    Gamma irradiation of onions and potatoes in order to increase their storage life, offers an alternative method to the conventional cold-storage (refrigeration) method. In this paper we discuss economical feasibility of this gamma irradiation method for commercial use. Gamma radiation emitted from source Co-60 (wet type 651) was used to irradiate onions and potatoes. Simultaneously, a cold-storage study was conducted using refrigeration (Fiocchetti Luzzary, CBE, Italy). The efficiency of the two methods, in the preservation of onions and potatoes for a storage period of 8 months, was compared by estimating the cost incurred for irradiation and refrigeration. The preservation cost by the irradiation method is estimated at 0.550 and 0.520 Libyan Dinars (1 L.D. = 3.30 US $) per Kg material for potatoes and onions respectively. In comparison with these costs, the refrigeration method works out at a higher cost of 0.730 and 0.960 Libyan Dinars per Kg material for potatoes and onions respectively. (author)

  13. An Automated Anion-Exchange Method forthe Selective Sorption of five Groups ofTrace Elements in Neutron-IrradiatedBiological Material

    International Nuclear Information System (INIS)

    Samsahl, K.

    1966-02-01

    An anion-exchange method based on fast selective sorption steps from mixtures of sulfuric, hydrobromic, and hydrochloric acid solutions has been developed for the separation of five different groups of radioactive trace elements in neutron-irradiated biological material. The separations are performed automatically with a simple proportioning pump apparatus. The apparatus allows the exact adjustment of influent solutions to the series of ion-exchange columns. The practical application of the method is described in detail. The successful use of the method is practically independent on the level of Na activity present in the sample

  14. Effect of irradiation on immobilized enzymes compared with that on enzymes in solution

    International Nuclear Information System (INIS)

    Schachinger, L.; Schippel, C.; Altmann, E.; Diepold, B.; Yang, C.; Jaenike, M.; Hochhaeuser, E.

    1985-01-01

    Glucose oxidase and catalase were immobilized by attaching them to nylon fibers that had been treated with triethyloxonium-tetrafluoroborate, diaminohexane and glutaraldialdehyde according to Morris, Campell and Hornby (1975). This method assures that the enzymes are bound to a side chain of the polyamide structure. Enzyme activity (as measured by the O 2 -uptake and by microcalorimetry) was found to be unchanged after 2 years. The apparent Ksub(m)-constants of the immobilized enzymes with glucose were the same as those for enzymes in solution. GOD and catalase immobilized in poly(acrylamide) gel had the same Ksub(m)-value. Despite the high stability during storage, the radiation induced inactivation of enzymes immobilized on gel or chromosorb, an inorganic carrier, was of the same order of magnitude as that of the dissolved enzymes. The enzymes bound to nylon fibers showed a higher radiation sensitivity. This might have been caused by an additional attack on the binding site of the carrier. (orig.)

  15. Resin bead-thermal ionization mass spectrometry for determination of plutonium concentration in irradiated fuel dissolver solution

    International Nuclear Information System (INIS)

    Paul, Sumana; Shah, R.V.; Aggarwal, S.K.; Pandey, A.K.

    2015-01-01

    Determination of isotopic composition (IC) and concentration of plutonium (Pu) is necessary at various stages of nuclear fuel cycle which involves analysis of complex matrices like dissolver solution of irradiated fuel, nuclear waste stream etc. Mass spectrometry, e.g. thermal ionization mass spectrometry (TIMS) and inductively coupled plasma mass spectrometry (ICP-MS) are commonly used for determination of IC and concentration of plutonium. However, to circumvent matrix interferences, efficient separation as well as preconcentration of Pu is required prior to mass spectrometric analysis. Purification steps employing ion-exchange resins are widely used for the separation of Pu from dissolver solution or from mixture of other actinides e.g. U, Am. However, an alternative way is to selectively preconcentrate Pu on a resin bead, followed by direct loading of the bead on the filament of thermal ionization mass spectrometer

  16. Tangential breast irradiation - rationale and methods for improving dosimetry

    International Nuclear Information System (INIS)

    Neal, A.J.; Mayles, W.P.M.; Yarnold, J.R.

    1994-01-01

    In recent years there have been great advances and innovations in all technical aspects of radiotherapy, including three dimensional (3D) computer planning, patient immobilization, radiation delivery and treatment verification. Despite this progress, the technique of tangential breast irradiation has changed little over this period and has not exploited these advances. There is increasing evidence that dose inhomogeneity within the breast is greater than at other anatomical sites, especially in women with large breasts. This paper is a review of the factors contributing to poor dosimetry in the breast, the clinical consequences of an inhomogeneous dose distribution, and how breast dosimetry could be improved by considering each of the stages from planning to accurate treatment delivery. It also highlights the particular problem of women with large breasts who may be more likely to have a poorer outcome after a fractionated course of radiotherapy than women with small/medium-sized breasts, and supports the clinical impression that such women are also more likely to have greater inhomogenicity when 3D treatment plans are examined. Preliminary data from our current computed tomography (CT) planning study are presented to support these observations. (author)

  17. Capillaric penetration of etchant solution into swift heavy ion-irradiated silicone rubber

    International Nuclear Information System (INIS)

    Fink, D.; Mueller, M.

    2000-01-01

    There is growing evidence that etchants penetrate into latent ion tracks in polymers from the very beginning, i.e., even during the so-called 'incubation time' when no visible etchant attack is observed. The model of capillaric penetration of viscous liquids into sponge-like matter agrees with experimental values both in their parametric dependence as in the absolute values. Our experiments are based on LiOH etching of both pristine and swift heavy ion-irradiated silicone rubber foils. About five times more etchant penetrates into irradiated than into pristine silicone rubber. The overall etchant penetration is highest in tracks parallel to the surface normal, and decreases with increasing ion track tilt angle towards the surface normal. The etchant penetration into the tracks proceeds relatively slowly with an effective viscosity comparable to that of heavy machine oil. When swelling starts to predominate, the maximum etchant penetration depth comes to saturation, with the total etchant uptake even decreasing

  18. Irradiation as an alternative environment friendly method for microbiological decontamination of herbal raw material

    International Nuclear Information System (INIS)

    Gorecki, P.; Kedzia, B.; Migdal, W.; Owczarczyk, H.B.

    1998-01-01

    Microbiological contamination of herbal raw materials is a serious problem in the production of therapeutical preparations. A good quality of the product, according to the pharmaceutical requirements may be achieved by applying suitable methods of decontamination. The decontamination treatments should be fast and effective against all microorganisms. It should ensure the decontamination of both packaging and the product in order to act effectively against all the microorganisms present and must not reduce the sensory and technological qualities of the commodities. In the paper, the results of comparative investigations on the microbiological decontamination of herbal raw materials by chemical (ethylene oxide, methyl bromide) and physical method (irradiation) are presented. Decontamination of herbal raw materials by irradiation is a method by choice. It is because chemical methods have been recognized recently as not safe to the consumer. Irradiation, in turn, is technically feasible, very effective and friendly enough to environment process

  19. A novel polyol method to synthesize colloidal silver nanoparticles by ultrasonic irradiation.

    Science.gov (United States)

    Byeon, Jeong Hoon; Kim, Young-Woo

    2012-01-01

    A polyol synthesis of silver nanoparticles in the presence of ultrasonic irradiation was compared with other configurations (at ambient temperature, 120° C, and 120 °C with injected solutions) in the absence of ultrasonic irradiation in order to obtain systematic results for morphology and size distribution. For applying ultrasonic irradiation, rather fine and uniform spherical silver particles (21±3.7 nm) were obtained in a simple (at ambient temperature without mechanical stirring) and fast (within 4 min, 3.61×10(-3) mol min(-1)) manner than other cases (at ambient temperature (for 8 h, 0.03×10(-3) mol min(-1)): 86±16.8 nm, 120 °C (for 12 min, 1.16×10(-3) mol min(-1)): 64±14.9 nm, and 120 °C with injected solutions (during 12 min): 35±6.8 nm; all other cases contained anisotropic shaped particles). Even though the temperature of polyol reaction reached only at 80 °C (silver particle and surrounding components) by ultrasonic irradiation might induce a better formation kinetics and morphological uniformity. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Role of aqueous electron and hydroxyl radical in the removal of endosulfan from aqueous solution using gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Noor S., E-mail: samadchemistry@gmail.com [Institute of Chemical Sciences, University of Swat, Swat 19130 (Pakistan); Radiation Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar 25120 (Pakistan); Khan, Javed Ali; Nawaz, Shah; Khan, Hasan M. [Radiation Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar 25120 (Pakistan)

    2014-08-15

    Highlights: • Removal of endosulfan was assessed by gamma irradiation under different conditions. • Removal of endosulfan by gamma irradiation was mainly due to reaction of aqueous electron. • The radiation yield value decreased while dose constant increased with increasing gamma-ray dose-rate. • Second-order rate constant of endosulfan with aqueous electron was determined by competition kinetic method. • Degradation pathways were proposed from the nature of identified by-products. - Abstract: The removal of endosulfan, an emerging water pollutant, from water was investigated using gamma irradiation based advanced oxidation and reduction processes (AORPs). A significant removal, 97% of initially 1.0 μM endosulfan was achieved at an absorbed dose of 1020 Gy. The removal of endosulfan by gamma-rays irradiation was influenced by an absorbed dose and significantly increased in the presence of aqueous electron (e{sub aq}{sup −}). However, efficiency of the process was inhibited in the presence of e{sub aq}{sup −} scavengers, such as N{sub 2}O, NO{sub 3}{sup −}, acid, and Fe{sup 3+}. The observed dose constant decreased while radiation yield (G-value) increased with increasing initial concentrations of the target contaminant and decreasing dose-rate. The removal efficiency of endosulfan II was lower than endosulfan I. The degradation mechanism of endosulfan by the AORPs was proposed showing that reductive pathways involving e{sub aq}{sup −} started at the chlorine attached to the ring while oxidative pathway was initiated due to attack of hydroxyl radical at the S=O bond. The mass balance showed 95% loss of chloride from endosulfan at an absorbed dose of 1020 Gy. The formation of chloride and acetate suggest that gamma irradiation based AORPs are potential methods for the removal of endosulfan and its by-products from contaminated water.

  1. A multigrid solution method for mixed hybrid finite elements

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, W. [Universitaet Augsburg (Germany)

    1996-12-31

    We consider the multigrid solution of linear equations arising within the discretization of elliptic second order boundary value problems of the form by mixed hybrid finite elements. Using the equivalence of mixed hybrid finite elements and non-conforming nodal finite elements, we construct a multigrid scheme for the corresponding non-conforming finite elements, and, by this equivalence, for the mixed hybrid finite elements, following guidelines from Arbogast/Chen. For a rectangular triangulation of the computational domain, this non-conforming schemes are the so-called nodal finite elements. We explicitly construct prolongation and restriction operators for this type of non-conforming finite elements. We discuss the use of plain multigrid and the multilevel-preconditioned cg-method and compare their efficiency in numerical tests.

  2. Method for determining correction factors induced by irradiation of ionization chamber cables in large radiation field

    International Nuclear Information System (INIS)

    Rodrigues, L.L.C.

    1988-01-01

    A simple method was developed to be suggested to hospital physicists in order to be followed during large radiation field dosimetry, to evaluate the effects of cables, connectors and extension cables irradiation and to determine correction factors for each system or geometry. All quality control tests were performed according to the International Electrotechnical Commission for three clinical dosimeters. Photon and electron irradiation effects for cables, connectors and extention cables were investigated under different experimental conditions by means of measurements of chamber sensitivity to a standard radiation source of 90 Sr. The radiation induced leakage current was also measured for cables, connectors and extension cables irradiated by photons and electrons. All measurements were performed at standard dosimetry conditions. Finally, measurements were performed in large fields. Cable factors and leakage factors were determined by the relation between chamber responses for irradiated and unirradiated cables. (author) [pt

  3. Temperature-dependent solute segregation in dilute Cu-Be under self-ion irradiation: a quantitative revision

    International Nuclear Information System (INIS)

    Koch, R.

    1993-01-01

    A reinvestigation of experimental data on solute precipitation behaviour in a Cu-1.35 at.%Be alloy subjected to Cu-ion irradiation has been carried out with regard to its strong dependence on the irradiation temperature in the range 400-700 K. A rate equation formalism presented in 1985 to describe the defect kinetics via mixed dumbbell formation and diffusion has been modified to take account of the redissolution of precipitated solutes into the matrix due to thermal vacancies. On the basis of the derived model this effect is shown to cause the observed reduction and disappearance of precipitation at high temperatures. Dumbbell dissociation and defect recombination with thermal vacancies become effective at still higher temperatures. The low-temperature decrease in precipitation is explained quantitatively by a marked change from the sink to the recombination case for point-defect annihilation. Moreover the whole temperature regime of precipitation is shown to shift to higher temperatures with increasing displacement rate. Both values of the activation enthalpies for migration and dissociation of the interstitial complex are given by analytical expressions and correspond to earlier estimates. (Author)

  4. Formation mechanism of solute clusters under neutron irradiation in ferritic model alloys and in a reactor pressure vessel steel: clusters of defects

    International Nuclear Information System (INIS)

    Meslin-Chiffon, E.

    2007-11-01

    The embrittlement of reactor pressure vessel (RPV) under irradiation is partly due to the formation of point defects (PD) and solute clusters. The aim of this work was to gain more insight into the formation mechanisms of solute clusters in low copper ([Cu] = 0.1 wt%) FeCu and FeCuMnNi model alloys, in a copper free FeMnNi model alloy and in a low copper French RPV steel (16MND5). These materials were neutron-irradiated around 300 C in a test reactor. Solute clusters were characterized by tomographic atom probe whereas PD clusters were simulated with a rate theory numerical code calibrated under cascade damage conditions using transmission electron microscopy analysis. The confrontation between experiments and simulation reveals that a heterogeneous irradiation-induced solute precipitation/segregation probably occurs on PD clusters. (author)

  5. The Semianalytical Solutions for Stiff Systems of Ordinary Differential Equations by Using Variational Iteration Method and Modified Variational Iteration Method with Comparison to Exact Solutions

    Directory of Open Access Journals (Sweden)

    Mehmet Tarik Atay

    2013-01-01

    Full Text Available The Variational Iteration Method (VIM and Modified Variational Iteration Method (MVIM are used to find solutions of systems of stiff ordinary differential equations for both linear and nonlinear problems. Some examples are given to illustrate the accuracy and effectiveness of these methods. We compare our results with exact results. In some studies related to stiff ordinary differential equations, problems were solved by Adomian Decomposition Method and VIM and Homotopy Perturbation Method. Comparisons with exact solutions reveal that the Variational Iteration Method (VIM and the Modified Variational Iteration Method (MVIM are easier to implement. In fact, these methods are promising methods for various systems of linear and nonlinear stiff ordinary differential equations. Furthermore, VIM, or in some cases MVIM, is giving exact solutions in linear cases and very satisfactory solutions when compared to exact solutions for nonlinear cases depending on the stiffness ratio of the stiff system to be solved.

  6. A method of beam control for NFZ-10 industrial irradiation linac

    International Nuclear Information System (INIS)

    Zhao Minghua

    2000-01-01

    Traditionally negative feedback coming from output beam is used to stabilize output beam by regulating filament voltage of bombarding diode electron gun. The authors analysed the shortcomings of the method in detail and put forward a new method of regulating bombarding high voltage in NFZ-10 industrial irradiation linac. Output beam with high stability and high accuracy was obtained

  7. On matrix diffusion: formulations, solution methods and qualitative effects

    Science.gov (United States)

    Carrera, Jesús; Sánchez-Vila, Xavier; Benet, Inmaculada; Medina, Agustín; Galarza, Germán; Guimerà, Jordi

    Matrix diffusion has become widely recognized as an important transport mechanism. Unfortunately, accounting for matrix diffusion complicates solute-transport simulations. This problem has led to simplified formulations, partly motivated by the solution method. As a result, some confusion has been generated about how to properly pose the problem. One of the objectives of this work is to find some unity among existing formulations and solution methods. In doing so, some asymptotic properties of matrix diffusion are derived. Specifically, early-time behavior (short tests) depends only on φm2RmDm / Lm2, whereas late-time behavior (long tracer tests) depends only on φmRm, and not on matrix diffusion coefficient or block size and shape. The latter is always true for mean arrival time. These properties help in: (a) analyzing the qualitative behavior of matrix diffusion; (b) explaining one paradox of solute transport through fractured rocks (the apparent dependence of porosity on travel time); (c) discriminating between matrix diffusion and other problems (such as kinetic sorption or heterogeneity); and (d) describing identifiability problems and ways to overcome them. RésuméLa diffusion matricielle est un phénomène reconnu maintenant comme un mécanisme de transport important. Malheureusement, la prise en compte de la diffusion matricielle complique la simulation du transport de soluté. Ce problème a conduit à des formulations simplifiées, en partie à cause de la méthode de résolution. Il s'en est suivi une certaine confusion sur la façon de poser correctement le problème. L'un des objectifs de ce travail est de trouver une certaine unité parmi les formulations et les méthodes de résolution. C'est ainsi que certaines propriétés asymptotiques de la diffusion matricielle ont été dérivées. En particulier, le comportement à l'origine (expériences de traçage courtes) dépend uniquement du terme φm2RmDm / Lm2, alors que le comportement à long terme

  8. Electroerosion method for preparation of saturated solutions of ruthenium hydroxochloride

    International Nuclear Information System (INIS)

    Mikhalev, V.A.; Andrianov, G.A.; Zhadanov, B.V.; Ryazanov, A.I.

    1987-01-01

    A pilot plant for carrying out electroerosion processes using pulse current of high unit power is developed. The solution process of metallic Ru in concentrated HCl is investigated. The possibility of preparation of ruthenium hydroxochloride solutions of 300 g/l concentration is established; it gives the possibility of Ru solution under conditions similar to the process of salting out

  9. Composition and method for solution mining of uranium ores

    International Nuclear Information System (INIS)

    Lawes, B.C.; Watts, J.C.

    1981-01-01

    It has been found that, in the solution mining of uranium ores using ammonium carbonate solutions containing hydrogen peroxide or ozone as an oxidant, the tendency of the formation being treated to become less permeable during the leaching process can be overcome by including in the leaching solution a very small concentration of sodium silicate

  10. Gamma irradiation of isocitric and citric acid in aqueous solution: Relevance in prebiotic chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Negrón-Mendoza, A., E-mail: negron@nucleares.unam.mx; Ramos-Bernal, S. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, UNAM. Cd. Universitaria, A. P. 70-543, 04510 México, D. F. México (Mexico)

    2015-07-23

    The radiation chemistry of hydroxy acids like citric and isocitric acids is rather scarce, even though they are crucial compounds in biological systems and for food irradiation. The aim of this work is to study the radiolytic behavior of these acids focused on the interconversion induced by radiation of citric and isocitric acid into other members of the Krebs cycle. The results showed that among the products formed were succinic, malonic, malic and other acids related to metabolic pathways, and these results are correlated with its possible role in chemical evolution processes.

  11. Method for regeneration of electroless nickel plating solution

    Science.gov (United States)

    Eisenmann, E.T.

    1997-03-11

    An electroless nickel(EN)/hypophosphite plating bath is provided employing acetic acid/acetate as a buffer and which is, as a result, capable of perpetual regeneration while avoiding the production of hazardous waste. A regeneration process is provided to process the spent EN plating bath solution. A concentrated starter and replenishment solution is provided for ease of operation of the plating bath. The regeneration process employs a chelating ion exchange system to remove nickel cations from spent EN plating solution. Phosphites are then removed from the solution by precipitation. The nickel cations are removed from the ion exchange system by elution with hypophosphorus acid and the nickel concentration of the eluate adjusted by addition of nickel salt. The treated solution and adjusted eluate are combined, stabilizer added, and the volume of resulting solution reduced by evaporation to form the bath starter and replenishing solution. 1 fig.

  12. Method for regeneration of electroless nickel plating solution

    Science.gov (United States)

    Eisenmann, Erhard T.

    1997-01-01

    An electroless nickel(EN)/hypophosphite plating bath is provided employing acetic acid/acetate as a buffer and which is, as a result, capable of perpetual regeneration while avoiding the production of hazardous waste. A regeneration process is provided to process the spent EN plating bath solution. A concentrated starter and replenishment solution is provided for ease of operation of the plating bath. The regeneration process employs a chelating ion exchange system to remove nickel cations from spent EN plating solution. Phosphites are then removed from the solution by precipitation. The nickel cations are removed from the ion exchange system by elution with hypophosphorous acid and the nickel concentration of the eluate adjusted by addition of nickel salt. The treated solution and adjusted eluate are combined, stabilizer added, and the volume of resulting solution reduced by evaporation to form the bath starter and replenishing solution.

  13. Matrix method for two-dimensional waveguide mode solution

    Science.gov (United States)

    Sun, Baoguang; Cai, Congzhong; Venkatesh, Balajee Seshasayee

    2018-05-01

    In this paper, we show that the transfer matrix theory of multilayer optics can be used to solve the modes of any two-dimensional (2D) waveguide for their effective indices and field distributions. A 2D waveguide, even composed of numerous layers, is essentially a multilayer stack and the transmission through the stack can be analysed using the transfer matrix theory. The result is a transfer matrix with four complex value elements, namely A, B, C and D. The effective index of a guided mode satisfies two conditions: (1) evanescent waves exist simultaneously in the first (cladding) layer and last (substrate) layer, and (2) the complex element D vanishes. For a given mode, the field distribution in the waveguide is the result of a 'folded' plane wave. In each layer, there is only propagation and absorption; at each boundary, only reflection and refraction occur, which can be calculated according to the Fresnel equations. As examples, we show that this method can be used to solve modes supported by the multilayer step-index dielectric waveguide, slot waveguide, gradient-index waveguide and various plasmonic waveguides. The results indicate the transfer matrix method is effective for 2D waveguide mode solution in general.

  14. Methods of using the quadratic assignment problem solution

    Directory of Open Access Journals (Sweden)

    Izabela Kudelska

    2012-09-01

    Full Text Available Background: Quadratic assignment problem (QAP is one of the most interesting of combinatorial optimization. Was presented by Koopman and Beckamanna in 1957, as a mathematical model of the location of indivisible tasks. This problem belongs to the class NP-hard issues. This forces the application to the solution already approximate methods for tasks with a small size (over 30. Even though it is much harder than other combinatorial optimization problems, it enjoys wide interest because it models the important class of decision problems. Material and methods: The discussion was an artificial intelligence tool that allowed to solve the problem QAP, among others are: genetic algorithms, Tabu Search, Branch and Bound. Results and conclusions: QAP did not arise directly as a model for certain actions, but he found its application in many areas. Examples of applications of the problem is: arrangement of buildings on the campus of the university, layout design of electronic components in systems with large scale integration (VLSI, design a hospital, arrangement of keys on the keyboard.

  15. Method for ion exchange purification of sodium iodide solution from heavy metals and potassium microimpurities

    International Nuclear Information System (INIS)

    Smirnov, G.I.; Kachur, N.Ya.; Kostromina, O.N.; Ogorodnikova, A.A.; Khajnakov, S.A.

    1990-01-01

    A method of deep ion exchange purification of sodium iodide solution from heavy metals (iron, nickel, copper, lead) and potassium microimpurities is developed. The method includes multiple sorption of microimpurities on titanium phosphate with their subsequent desorption by sorbent processing with a solution with a solution of 3-6 N nitric acid, first, and then with a neutral solution of 2 % sodium thiosulfate. The given method permits to increase the purification degree of sodium iodide solution by 25-30 %. 2 tabs

  16. Growth and sedimentation of fine particles produced in aqueous solutions of palladium sulfate and palladium sulfate-silver sulfate induced by gamma-ray irradiation

    International Nuclear Information System (INIS)

    Hatada, Motoyoshi; Jonah, C.D.

    1994-10-01

    It is known that palladium and palladium-silver fine particles were formed from deaerated aqueous solutions of palladium sulfate and palladium sulfate-silver sulfate induced by gamma-ray irradiation. Changes in particle size and with amount of particles in the solution with time during and after irradiation were studied using dynamic light scattering technique and UV spectrophotometer. The particles formed from palladium sulfate solution are found to be water-filled bulky particles of diameter of 200 nm, which grow by mutual coagulation even after irradiation was terminated. Average density depends on concentration of palladium ion in the solution and dose, and the lowest density was about 2 g/cm 3 for particles of 200 nm obtained from 0.06 mM solution by 2.4 kGy irradiation. The average density of the particles obtained from palladium sulfate-silver sulfate solutions was smaller than those obtained for the corresponding palladium sulfate solutions. Supersonic agitation destroyed coagulated precipitates to form fine particles, but did not form clusters of a few atoms. (author)

  17. New Exact Solutions of Time Fractional Gardner Equation by Using New Version of F -Expansion Method

    International Nuclear Information System (INIS)

    Pandir, Yusuf; Duzgun, Hasan Huseyin

    2017-01-01

    In this article, we consider analytical solutions of the time fractional derivative Gardner equation by using the new version of F-expansion method. With this proposed method multiple Jacobi elliptic functions are situated in the solution function. As a result, various exact analytical solutions consisting of single and combined Jacobi elliptic functions solutions are obtained. (paper)

  18. SU-E-T-492: Implementing a Method for Brain Irradiation in Rats Utilizing a Commercially Available Radiosurgery Irradiator

    International Nuclear Information System (INIS)

    Cates, J; Drzymala, R

    2014-01-01

    Purpose: The purpose of the study was to implement a method for accurate rat brain irradiation using the Gamma Knife Perfexion unit. The system needed to be repeatable, efficient, and dosimetrically and spatially accurate. Methods: A platform (“rat holder”) was made such that it is attachable to the Leskell Gamma Knife G Frame. The rat holder utilizes two ear bars contacting bony anatomy and a front tooth bar to secure the rat. The rat holder fits inside of the Leskell localizer box, which utilizes fiducial markers to register with the GammaPlan planning system. This method allows for accurate, repeatable setup.A cylindrical phantom was made so that film can be placed axially in the phantom. We then acquired CT image sets of the rat holder and localizer box with both a rat and the phantom. Three treatment plans were created: a plan on the rat CT dataset, a phantom plan with the same prescription dose as the rat plan, and a phantom plan with the same delivery time as the rat plan. Results: Film analysis from the phantom showed that our setup is spatially accurate and repeatable. It is also dosimetrically accurate, with an difference between predicted and measured dose of 2.9%. Film analysis with prescription dose equal between rat and phantom plans showed a difference of 3.8%, showing that our phantom is a good representation of the rat for dosimetry purposes, allowing for +/- 3mm diameter variation. Film analysis with treatment time equal showed an error of 2.6%, which means we can deliver a prescription dose within 3% accuracy. Conclusion: Our method for irradiation of rat brain has been shown to be repeatable, efficient, and accurate, both dosimetrically and spatially. We can treat a large number of rats efficiently while delivering prescription doses within 3% at millimeter level accuracy

  19. Evaluation of identification methods of irradiated spices and dehydrated vegetables in Brazil

    International Nuclear Information System (INIS)

    Bernardes, D.M.L.; Del Mastro, N.L.

    1998-01-01

    Complete text of publication follows. This paper deals with the use of analytical methods to determine whether imported or for export Brazilian spices and dehydrated vegetables were irradiated. Viscosimetry, thermoluminescence (TL) and electron spin resonance (ESR) were used for the identification of some irradiated products: black pepper, white pepper, cinnamon, nutmeg, garlic, cumin, oregano, celery, paprika and coriander. Viscosimetry was performed in suspensions of irradiated spices and dehydrated vegetables which had been gellified by heat. Thermoluminescence (TL) is based on the transference of electrons to an excited state by radiation with emission of light when the electrons are thermally stimulated. The thermoluminescent signal of spices can be explained by the presence of mineral grains adhering on the surface of the samples. Free radicals produced by irradiation of spices were analyzed by electron spin resonance (EPR) signals. The results of this study lead to the conclusion that viscosimetry, thermoluminescence and electron spin resonance are analytical methods that can be use to detect whether spices and dehydrated vegetables were irradiated, specially when a combination of different methods was used

  20. Long-term storage method for soft X-ray irradiated 'Hyuganatsu' pollen

    International Nuclear Information System (INIS)

    Yano, S.; Tanaka, M.; Ohara, N.

    2008-01-01

    The long-term storage conditions for 'Hyuganatsu ' pollen that had been irradiated with soft X-rays was examined. This study, was aimed at production of 'Tosa-buntan' without formation of nuclear fruit. 1. We evaluated the germination rate of pollen that had been irradiated with soft X-ray (500 or 1,000 Gy) and stored at 3 deg C, -20 deg C, and -40 deg C. The germination rate was the same as that of unirradiated pollen, even after storage for 1 year. Soft X-ray irradiation did not influence the storage attributes of pollen. 2. In unirradiated pollen and pollen that had been irradiated with soft X-ray (500 or 1,000 Gy), temperature conditions necessary for storing from 3 months to 1 year were -20 deg C or less, and pollen stored at -40 deg C had a higher germination rate after 1 year. 3. The germination rate was 1% or less in 4 months if silica gel was sealed into a gas barrier bag with 1,000 Gy-irradiated pollen at a rate of 10:1 (w/w). The ability to germinate was completely lost after 1 year in these conditions. 4. We evaluated the effect of sealing methods on 1,000 Gy-irradiated pollen stored at -20 deg C. There was no difference in germination rates among pollen stored in gas-barrier bags, vacuum-packaged pollen, and pollen stored with nitrogen in gas-barrier bags. Moreover, the germination rate of 750 Gy-irradiated pollen stored at -20 deg C decreased from 3 months onwards when pollen was stored with a free-oxygen absorber (Ageless ZP). 5. Pollen that was treated with acetone before or after soft X-ray irradiation (750 Gy) withstood long-term storage of 1 year. Long-term storage was possible if pollen was stored at -20 deg C, as is the case for rough pollen

  1. Two micro fatigue test methods for irradiated materials

    International Nuclear Information System (INIS)

    Nunomura, Shigetomo; Noguchi, Shinji; Okamura, Yuichi; Kumai, Shinji

    1993-01-01

    This paper demonstrates two miniature fatigue test methods in response to the requirements of the fusion reactor wall materials development program. It is known that the fatigue strength evaluated by the axial loading test is independent of the specimen size, while that evaluated by the bend test or torsion test is dependent upon the size of specimen. The new type of gripping system for the axial, tension-tension, fatigue testing of TEM disk-size specimens that has been developed is described in this paper. An alignment tool assists in gripping the miniature specimen. The miniature tension-tension fatigue test method seems to provide reliable S-N curves for SUS304 and SUS316L stainless steels. An indentation method has also been developed to determine fatigue properties. A hard steel ball or ceramic ball was used for cyclically loading the specimen, and an S-N curve was subsequently obtained. The merit of this method is primarily simple handling. S-N curves obtained from four materials by this indentation method compared well with those obtained from the rotary bend fatigue test employing a standard-size specimen

  2. Effect of phase instabilities on the correlation of nickel ion and neutron irradiation swelling in solution annealed 316 stainless steel

    International Nuclear Information System (INIS)

    Rowcliffe, A.F.; Lee, E.H.; Sklad, P.S.

    1979-01-01

    Annealed 316 stainless steel specimens were neutron irradiated to establish steady-state microstructures and then subjected to further high temperature irradiations with 4 MeV Ni ions. It is shown that void growth under neutron irradiation is simulated in ion irradiations carried out at approx. 180 0 C above reactor temperature. However, the precipitate microstructure developed during neutron irradiation is unstable during subsequent ion irradiation. As a result, the relative swelling rates at various reactor temperatures are not simulated correctly

  3. Effect of irradiation and cooking methods on ascorbic acid levels of four potato cultivars

    International Nuclear Information System (INIS)

    Shirsat, S.G.; Thomas, Paul

    1998-01-01

    The changes in reduced and total ascorbic acid (AA) contents in control and in tubers irradiated to 100 Gy gamma rays for sprout inhibition were studied by HPLC and iodophenol titrimetry methods in four potato cultivars as a function of storage at 15 degC and after cooking by different methods. Both reduced and total ascorbic acid levels decreased in control tubers during the first 3 months in storage recording respectively 22 to 35% and 26 to 45% losses depending on the cultivar. Irradiated tubers recorded additional losses of 5 to 10% and 6.5 to 13%, respectively in reduced and total ascorbic acid levels during the same period but remained in good marketable conditions. Cooking of tubers in boiling water showed maximum loss in vitamin C content, whereas pressure and microwave cooking recorded least losses. The magnitude of losses in reduced and total vitamin C during cooking was comparable in control and in irradiated tubers. (author)

  4. A TEM method for analyzing local strain fields in irradiated materials

    International Nuclear Information System (INIS)

    Bennetch, J.I.; Jesser, W.A.

    1983-01-01

    Of great interest to the field of fracture mechanics is the strain field in front of a crack tip. In irradiated materials, cavities which naturally form as a result of radiation provide convenient internal markers. If a miniaturized irradiated tensile sample is pulled in situ in a transmission electron microscope (TEM), both the relative displacement of these cavities and their distortion in shape provide information on localized strain on a microscopic level. In addition, the TEM method allows direct correlation of active slip systems with crack propagation characteristics. To illustrate this method a strain field map was constructed about a crack propagating in a helium irradiated type 316 stainless steel sample containing large cavities. (orig.)

  5. Detection of irradiated fruits and vegetables by gas-chromatographic methods and electron spin-resonance

    Energy Technology Data Exchange (ETDEWEB)

    Farag, S.E.A. (National Centre for Radiation Research and Technology, Cairo (Egypt))

    1993-01-01

    Gas chromatographic methods detected some hydrocarbons esp. 17:1, 16:2, 15:0 and 14:1 in irradiated, Avocado, Papaya, Mangoes with 0.75, 1.5, 3.0 kGy and Apricot with 0.5 and 3.0 kGy. The detection of hydrocarbons was clearly at high doses but the low doses need more sensitive conditions using Liquid-Liquid-Gas chromatographic method as used here. Using Electron Spin-Resonance, produce a specific signal from irradiated onion (dried leaves) as well as apricot (hard coat of kernels) after some weeks of irradiation process but not clear with the other foodstuffs. (orig.)

  6. A method for sorting irradiated substances according to their color

    International Nuclear Information System (INIS)

    Sawyer, Baldwin.

    1974-01-01

    Description is given of a method for isolating quartz, quartzit, glass or silicate-containing substances with known contents of aluminium. That nondestructive method comprises the step of exposing said substances to an ionizing radiation for a sufficient duration and with a sufficent intensity for developing the various colors typical of the substances containing aluminium ions. Depending on the ions associated with the aluminiums ions, the intensity of each of the developed colors corresponds to the amount of aluminium contained in the crystals. In this way, aluminium-free quartz, quartzit, glass or silicate-containing substances can be isolated if they exist in a mixture containing portions of said substances each of which has a known uniform aluminium content [fr

  7. Comparison of different chlorophenols degradation in aqueous solutions by gamma irradiation under reducing conditions

    International Nuclear Information System (INIS)

    Peng, Yunxia; He, Shijun; Wang, Jianlong; Gong, Wenqi

    2012-01-01

    The reductive degradation of chlorophenols (CPs), including 2-CP, 4-CP and 2,4-DCP by gamma irradiation was investigated and compared. The results showed that the most efficient degradation took place with 2,4-DCP, followed by 2-CP and then 4-CP. This confirmed that the number and position of chlorine atoms existing in the benzene ring have significant impact on dechlorination and decomposition of CPs. The G-values of decomposition of CPs, the formation of intermediate products and chloride ion, and the degradation rate (K CPs and K Cl −1 ) were also determined. - Highlights: ► Reductive degradation of 2-CP, 4-CP and 2,4-DCP by γ radiation was compared. ► Number and position of chlorine affect their dechlorination and decomposition. ► G-values of CPs decomposition, intermediate formation and chloride release were determined.

  8. Epimerization of Alanyl-Alanine Induced by γ-Rays Irradiation in Aqueous Solutions

    Science.gov (United States)

    Munegumi, Toratane

    2017-03-01

    Living organisms have homochiral L-amino acids in proteins and homochiral D-mononucleotides in nucleic acids. The chemical evolutionary process to protein homochirality has been discussed for many years. Although many scenarios have been proposed for homochirality in the monomeric compounds, homochirality in amino acids and mononucleotides does not always guarantee homochirality in polypeptides and polynucleotides. Integrated scenarios containing the pathways from monomer to polymer should be proposed because in the pathways oligomers and polymers as well as monomers racemize (or epimerize), degrade, and condense. This research addresses epimerization and degradation of dipeptides under γ-rays irradiation by a cobalt-60 (60Co) radiation source. The different rate constants of epimerization between diastereomeric dipeptides in the research suggest that the potential pathway toward homochirality could be much more complex.

  9. Uniform irradiation using rotational-linear scanning method for narrow synchrotron radiation beam

    International Nuclear Information System (INIS)

    Nariyama, N.; Ohnishi, S.; Odano, N.

    2004-01-01

    At SPring-8, photon intensity monitors for synchrotron radiation have been developed. Using these monitors, the responses of radiation detectors and dosimeters to monoenergetic photons can be measured. In most cases, uniform irradiation to the sample is necessary. Here, two scanning methods are proposed. One is an XZ-linear scanning method, which moves the sample simultaneously in both the X and Z direction, that is, in zigzag fashion. The other is a rotational-linear scanning method, which rotates the sample moving in the X direction. To investigate the validity of the two methods, thermoluminescent dosimeters were irradiated with a broad synchrotron-radiation beam, and the readings from the two methods were compared with that of the dosimeters fixed in the beam. The results for both scanning methods virtually agreed with that of the fixed method. The advantages of the rotational-linear scanning method are that low- and medium-dose irradiation is possible, uniformity is excellent and the load to the scanning equipment is light: hence, this method is superior to the XZ-linear scanning method for most applications. (author)

  10. Methods for measuring risk-aversion: problems and solutions

    International Nuclear Information System (INIS)

    Thomas, P J

    2013-01-01

    Risk-aversion is a fundamental parameter determining how humans act when required to operate in situations of risk. Its general applicability has been discussed in a companion presentation, and this paper examines methods that have been used in the past to measure it and their attendant problems. It needs to be borne in mind that risk-aversion varies with the size of the possible loss, growing strongly as the possible loss becomes comparable with the decision maker's assets. Hence measuring risk-aversion when the potential loss or gain is small will produce values close to the risk-neutral value of zero, irrespective of who the decision maker is. It will also be shown how the generally accepted practice of basing a measurement on the results of a three-term Taylor series will estimate a limiting value, minimum or maximum, rather than the value utilised in the decision. A solution is to match the correct utility function to the results instead

  11. Methods for measuring risk-aversion: problems and solutions

    Science.gov (United States)

    Thomas, P. J.

    2013-09-01

    Risk-aversion is a fundamental parameter determining how humans act when required to operate in situations of risk. Its general applicability has been discussed in a companion presentation, and this paper examines methods that have been used in the past to measure it and their attendant problems. It needs to be borne in mind that risk-aversion varies with the size of the possible loss, growing strongly as the possible loss becomes comparable with the decision maker's assets. Hence measuring risk-aversion when the potential loss or gain is small will produce values close to the risk-neutral value of zero, irrespective of who the decision maker is. It will also be shown how the generally accepted practice of basing a measurement on the results of a three-term Taylor series will estimate a limiting value, minimum or maximum, rather than the value utilised in the decision. A solution is to match the correct utility function to the results instead.

  12. EPR of gamma irradiated solid sucrose and UV spectra of its solution. An attempt for calibration of solid state/EPR dosimetry

    International Nuclear Information System (INIS)

    Yordanov, N.D.; Karakirova, Y.

    2007-01-01

    A simple new approach for independent calibration of solid state/EPR (SS/EPR) dosimetry system is reported. It is based on the fact that: (i) gamma-irradiation of solid sucrose (sugar) induces stable EPR detectable free radicals accompanied by UV detectable brown colour stable in the solid state and in solution; (ii) both the EPR intensity of gamma-irradiated solid sucrose and its solution UV absorbance linearly depend on the absorbed dose high energy radiation and may be independently used for dosimetric purpose; (iii) UV spectrometers are calibrated. The correlation between EPR response and absorbed dose radiation of solid sucrose and UV absorption of its solutions is used in the present communication for calibration purpose. The procedure of sucrose extraction from sucrose-paraffin dosimeters is described. The calibration procedure may be applied to any other (alanine, self-calibrated, etc.) SS/EPR dosimeters, simultaneously irradiated with sucrose

  13. A Visualization Technique for Accessing Solution Pool in Interactive Methods of Multiobjective Optimization

    OpenAIRE

    Filatovas, Ernestas; Podkopaev, Dmitry; Kurasova, Olga

    2015-01-01

    Interactive methods of multiobjective optimization repetitively derive Pareto optimal solutions based on decision maker’s preference information and present the obtained solutions for his/her consideration. Some interactive methods save the obtained solutions into a solution pool and, at each iteration, allow the decision maker considering any of solutions obtained earlier. This feature contributes to the flexibility of exploring the Pareto optimal set and learning about the op...

  14. Study of the lattice parameter evolution of PWR irradiated MOX fuel by X-Ray diffraction; Etude de l'evolution du parametre cristallin des combustibles MOX irradies en rep par la methode de diffraction des rayons X

    Energy Technology Data Exchange (ETDEWEB)

    Clavier, B

    1995-07-01

    Fuel irradiation leads to a swelling resulting from the formation of gaseous (Kr, Xe) or solid fission products which are found either in solution or as solid inclusions in the matrix. This phenomena has to be evaluated to be taken into account in fuel cladding Interaction. Fuel swelling was studied as a function of burn up by measuring the corresponding cell constant evolution by X-Ray diffraction. This study was realized on Mixed Oxide Fuels (MOX) irradiated in a Pressurized Water Reactor (PWR) at different burn-up for 3 initial Pu contents. Lattice parameter evolutions were followed as a function of burn-up for the irradiated fuel with and without an annealing thermal treatment. These experimental evolutions are compared to the theoretical evolutions calculated from the hard sphere model, using the fission product concentrations determined by the APPOLO computer code. Contribution of varying parameters influencing the unit cell value is discussed. Thermal treatment effects were checked by metallography, X-Ray diffraction and microprobe analysis. After thermal treatment, no structural change was observed but a decrease of the lattice parameter was measured. This modification results essentially from self-irradiation defect annealing and not from stoichiometry variations. Microprobe analysis showed that about 15% of the formed Molybdenum is in solid solution In the oxide matrix. Micrographs showed the existence of Pu packs in the oxide matrix which induces a broadening of diffraction lines. The RIETVELD method used to analyze the X-Ray patterns did not allow to characterize independently the Pu packs and the oxide matrix lattice parameters. Nevertheless, with this method, the presence of micro-strains in the irradiated nuclear fuel could be confirmed. (author)

  15. On the mechanism of dechlorination of polychlorinated biphenyls (PCBs) induced by electron beam irradiation in aqueous and aqueous micellar solutions, transformer oil, and sediment

    International Nuclear Information System (INIS)

    Chaychian, M.; Silverman, J.; Al-Sheirkhly, M.

    2011-01-01

    Complete text of publication follows. The widespread release of PCBs into the environment presents a serious problem due to their persistence and toxicity. Ionizing radiation, such as gamma rays and high-energy electron beam, is remarkably effective in dechlorinating PCBs into biphenyls. The kinetics of the reductive dechlorination of PCBs in aqueous and aqueous micellar solutions and in transformer oil is being studied by pulse radiolysis and steady-state radiolysis. In aqueous micellar solutions, dichlori-, tetrachloro-, and decachlorobiphenyl congeners were solubilized in water using a commercially available non-ionic surfactant, Triton X-100, and subsequently pulse irradiated by electron accelerator using optical detection method. The reaction rate constant between decachlorobiphenyl and aqueous electrons e aq ·- , and Triton with e aq ·- in the 2% Triton solution, were measured as 2.6 x 10 9 Lmol -1 s -1 and 1.2 x 10 7 Lmol -1 s -1 , respectively. We have also measured in aqueous solutions, the reaction rate constant of e aq ·- with dichlorobiphenyl as 3.8 x 10 9 Lmol -1 s -1 . In aqueous-propanol, the reaction rate constants of e aq ·- with dichlorobiphenyl, tetrachlorobiphenyl, and dechachlorobiphenyl are 2 x 10 9 Lmol -1 s -1 , 3 x 10 9 Lmol -1 s -1 , and 7 x 10 9 Lmol -1 s -1 , respectively. In addition to the presence of PCBs as high-dielectric component, transformer oil contains many aromatic hydrocarbons; the most abundant being biphenyl, fluorine, and phenanthrene. Solvated electrons formed by irradiation of the oil react either with PCB to lead to dechlorination or with the aromatic hydrocarbons present in the oil to form radical anions. These species are shown to transfer an electron to chlorinated biphenyls relative rapidly, leading to dechlorination. The rate constants for several such reactions, determined in 2-propanol solutions, are in the range of 10 7 - 10 8 Lmol -1 s -1 . These rapid reactions explain why PCB can be dechlorinated in oil

  16. Gas evolution as a rapid screening method for detection of irradiated foods

    International Nuclear Information System (INIS)

    Roberts, P.B.; Chambers, D.M.; Brailsford, G.W.

    1996-01-01

    A number of detection methods for irradiated foods are in advanced state of development. No single method is likely to be universally applicable but a battery of tests such as thermoluminescence, electron spin resonance and analysis of lipid radiolytic products may soon be available for most foods and technical uses of irradiation. Most of these proposed tests require relatively sophisticated equipment or technical skills and are often time consuming and costly. There would be value in relatively simple tests which could be used as a rapid screening system or confirmatory method. The literature on the use of radiolytic gases as a detection method is limited and this paper extends the above studies. In particular, it extends the work to frozen shellfish, for which irradiation has been used as a commercial decontaminant technique for many years, and considers the effect of storage temperature. Work on poultry is also reported as a cross-reference to earlier work and because irradiated poultry has recently been released into the US retail trade. (author)

  17. Evaluate of environment quality for γ irradiation facilities using fuzzy comprehensive judgment method

    International Nuclear Information System (INIS)

    Ha Yiming

    2002-01-01

    The environment quality of Jining Irradiation Centre new γ radiation facility was evaluated by fuzzy comprehensive judgment method. The result showed that the place of γ radiation facility was well and the measures of radiate shelter and environment protect were effective. The environment quality of its area was not obvious change and the result of environment evaluation was first-rate

  18. New method of investigation of urine microflora in mice after irradiation

    Directory of Open Access Journals (Sweden)

    Ivanov A.A.

    2013-12-01

    nated with one drop of urine, placed on surface Endo media, incubate in thermostat (37°C in during 1-2 days and numbers of positive crops (Esch. coli, Proteus, Enterococcus, were indicated. It was shown that after irradiation the numbers of positive probes increased. The test displayed that the method is easy, economic and demonstrative.

  19. No effect of the hemoglobin solution HBOC-201 on the response of the rat R1H tumor to fractionated irradiation

    International Nuclear Information System (INIS)

    Raabe, A.

    2005-01-01

    Background and Purpose: Tumor hypoxia is regarded as one important underlying feature of radioresistance. The authors report on an experimental approach to improve tumor response to radiation by combining fractionated irradiation with HBOC-201, an ultrapurified polymerized hemoglobin solution, which is currently used in clinical phase II/III trials as alternative oxygen carrier and proved to be highly effective in tissue oxygenation (tpO 2 ). Material and Methods: Subcutaneously growing rhabdomyosarcoma R1H tumors of the rat were treated with either 40 Gy (2 Gy/fraction, 20 fractions in 2 weeks, ambient) followed by grade top-up doses (clamped) alone, or in combination with HBOC-201, or with HBOC-201 plus carbogen (95% O 2 +5% CO 2 ). Local tumor control (TCD50%) and growth delay were used as endpoints. In addition, the effect of HBOC-201 alone or in combination with carbogen on the tpO 2 of tumor and muscle was determined using a flexible stationary probe (Licox, GMS). Results: TCD50% values of 119 Gy (95% confidence interval 103; 135), 111 Gy (84; 138), and 102 Gy (83; 120) were determined for tumors irradiated alone, in combination with HBOC-201, and with HBOC-201 plus carbogen, respectively. Although the dose-response curves showed a slight shift to lower doses when HBOC-201 or HBOC-201 plus carbogen was added, the differences in TCD50% were not statistically significant. No effect was seen on the growth delay of recurrent tumors. HBOC-201 alone did not effect tumor or muscle tpO 2 . In combination with carbogen the mean tpO 2 muscle raised from 23.9 mmHg to 59.3 mmHg (p 2 by carbogen alone. Conclusion: Low-dose application of HBOC-201 does not improve the response of the rhabdomyosarcoma R1H of the rat to fractionated irradiation. (orig.)

  20. Tensometrical properties of volumetric crystals of germanium-silicon solid solutions irradiated by fast electrons

    International Nuclear Information System (INIS)

    Abbasov, Sh.M.

    2002-01-01

    Full Text: In the present work the tensometrical properties of Ge1-xSix solid solution monocrystal contended of up to 15 at. % Si were investigated. The radiation-proof strain gauges of researched crystals were made. For this purpose the site was cutted out from a sample, perpendicularly or in parallel of a crystal axes. After polishing the samples had thickness of 30-40 microns, and length of 2 mm

  1. Molecular dynamics study of interstitial-solute interactions in irradiated Al-based alloys

    International Nuclear Information System (INIS)

    Doan, N.V.; Lam, N.Q.; Dagens, L.; Adda, Y.

    1981-11-01

    The stable configurations and binding energies of interstitial and di-interstitial-solute complexes in Al-Be, Al-Ca, Al-K, Al-Li, Al-Mg and Al-Zn alloys were calculated using the molecular dynamics technique in conjunction with interatomic potentials derived entirely from theoretical considerations and not fitted to any experimental data. All the results reported in this work are thus of first-principles nature

  2. Irradiation as an alternative environmentally friendly method for microbiological decontamination of herbal raw material

    International Nuclear Information System (INIS)

    Dragusin, M.; Rotaru, R.

    2000-01-01

    Microbiological contamination of herbal raw materials is a serious problem in the production of therapeutical preparations. A good quality of the product, according to the pharmaceutical requirements may be achieved by applying suitable methods of decontamination. The decontamination treatments should be fast and effective against all microorganisms. It should ensure the decontamination of both packaging and the microorganisms present and must not reduce the sensory and technological qualities of the commodities. Decontamination of herbal raw materials by irradiation is a method by choice. It is because chemical methods are recognized recently as not safe to the consumer. Irradiation, in turn, is technically feasible, very effective and friendly enough to environment process. Under the prevailing production and handling conditions, most herbs contain a large number of microorganisms what is a serious problem in the production of therapeutical preparations. For several years the most widely used methods for decontamination of herbs was fumigation with ethylene oxide or methyl bromide. Both methods today banned in most countries. Irradiation is an alternative and safe method for effective reducing the microbial contamination of herbal raw materials. The following raw materials have been examined: Folium Cynara, Folium Plantago, Flos Chamomillae, Semen Sylibum Marianum and Folium Farfara. The content of biologically active compounds before and after irradiation of the raw materials did not change in a significant degree after irradiation. The dose of radiation for herbals raw materials was 10 kGy. There are two groups of raw materials: - The raw materials designed for preparing granulates, tablets, dragees, capsules, aqueous extracts, infusions, macerations and preparations for external use; - The raw materials assigned for preparing alcoholic preparations, isolated compounds, oil preparations and essential oils. The medical herbs and herbal raw materials before their

  3. Application of a microbiological screening method for the indication of irradiation of poultry meat

    International Nuclear Information System (INIS)

    Wirtanen, G.; Karwoski, M.; Sjoberg, A.-M.; Salo, S.

    1996-01-01

    The FDA (Food and Drug Administration of the Department of Health and Human Services, USA) ruling of May 1990 permits the use of irradiation of fresh or frozen poultry and poultry parts, including ground and mechanically separated poultry products, at absorbed doses of 1.5 to 3 kGy to control foodborne pathogens and bacteria. The aim of this study was to apply a microbiological method (DEFT/APC) to assess the possible irradiation treatment of samples of frozen poultry meat. (author)

  4. Some elaborating methods of gamma scanning results on irradiated nuclear fuels

    International Nuclear Information System (INIS)

    Sternini, E.

    1979-01-01

    Gamma scanning, as a post-irradiation examination, is a technique which provides a large number of informations on irradiated nuclear fuels. Power profile, fission products distribution, average and local burn-up of single elements structural and nuclear behaviour of fuel materials are examples of the obtained informations. In the present work experimental methods and theoretical calculations used at the CNEN hot cell laboratory for the mentioned purposes are described. Errors arising from the application of the gamma scanning technique are also discussed

  5. Synthesis and photocatalytic degradation study of methylene blue dye under visible light irradiation by Fe1-xBixVO4 solid solutions (0 ≤ x ≤ 1.0)

    Science.gov (United States)

    Bera, Ganesh; Reddy, V. R.; Mal, Priyanath; Das, Pradip; Turpu, G. R.

    2018-05-01

    The novel hetero-structures Fe1-xBixVO4 solid solutions (0 ≤ x ≤ 1.0) with the two dissimilar end member of FeVO4 - BiVO4, were successfully synthesized by the standard solid state reaction method. The structural and chemical properties of as prepared photo-catalyst samples were characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and UV-visible absorption spectroscopy techniques. It is confirmed from the results of XRD, Raman and FT-IR that FeVO4 and BiVO4 are in triclinic (space group P-1 (2)) and monoclinic (space group I2/b (15)) phases respectively. The Bi incorporation into Fe site of FeVO4 emerges as hetero-structures of both the end members of the solid solutions. In addition, the photocatalytic activity in the degradation of methylene blue (MB) dye under visible light irradiation was carried out through UV-visible spectroscopy measurement of photo-catalysts FeVO4, BiVO4 and mixed phases of both photo-catalyst. The results indicate that under visible light irradiation the photocatalytic activity of mixed phases were very effective and higher than the both single phases of the solid solutions. The composition x= 0.25 exhibits an excellent photocatalytic property for the degradation of MB solution under visible light irradiation rather than other.

  6. Kinetics of polymer degradation in solution. 6. Laser flash photolysis and pulse radiolysis studies of polymethylvinylketone in solution using the light scattering detection method

    Energy Technology Data Exchange (ETDEWEB)

    Lindenau, D; Beavan, S W; Beck, G; Schnabel, W [Hahn-Meitner-Institut fuer Kernforschung Berlin G.m.b.H. (Germany, F.R.)

    1977-01-01

    Polymethylvinylketone (PMVK) was irradiated in solution with 2 ..mu..s pulses of 15 MeV electrons or with 15 ns flashes of 262 nm light. The change of the intensity of the light scattered by the solution (LSI) after the irradiation was measured. For the radiolysis experiments, a main chain scission process tausub(1/2) (decr) approximately 20 ..mu..s) and a subsequent crosslinking process (tausub(1/2) (incr) approximately 0.4 sec) could be discriminated. The LSI change pertaining to the main chain degradation was found to be due to disentanglement diffusion, whereas the LSI change pertaining to the crosslinking process could be correlated to a chemical reaction. The rate constant for combination of lateral macroradicals in acetone solution was estimated as 2 k/sub 2/ - (4.5 +- 1.5)10/sup 6/ M/sup -1/ sec/sup -1/. Stationary irradiation with /sup 60/Co-..gamma..-rays showed that PMVK is predominantly crosslinked to form a macrogel when irradiated in the solid state or in solution at concentrations greater than 100 g/l. At lower concentrations, microgel formation occurred. Photolysis of PMVK in solution yielded only main chain degradation. The LSI change was found to be due to disentanglement diffusion as during radiolysis. It was concluded that the same mechanism for main chain rupture is operative as in radiolysis. Stationary irradiations with uv light (lambda > 260 nm ) resulted in main chain degradation; no indication of crosslinking was obtained.

  7. Multiple Revolution Solutions for the Perturbed Lambert Problem using the Method of Particular Solutions and Picard Iteration

    Science.gov (United States)

    Woollands, Robyn M.; Read, Julie L.; Probe, Austin B.; Junkins, John L.

    2017-12-01

    We present a new method for solving the multiple revolution perturbed Lambert problem using the method of particular solutions and modified Chebyshev-Picard iteration. The method of particular solutions differs from the well-known Newton-shooting method in that integration of the state transition matrix (36 additional differential equations) is not required, and instead it makes use of a reference trajectory and a set of n particular solutions. Any numerical integrator can be used for solving two-point boundary problems with the method of particular solutions, however we show that using modified Chebyshev-Picard iteration affords an avenue for increased efficiency that is not available with other step-by-step integrators. We take advantage of the path approximation nature of modified Chebyshev-Picard iteration (nodes iteratively converge to fixed points in space) and utilize a variable fidelity force model for propagating the reference trajectory. Remarkably, we demonstrate that computing the particular solutions with only low fidelity function evaluations greatly increases the efficiency of the algorithm while maintaining machine precision accuracy. Our study reveals that solving the perturbed Lambert's problem using the method of particular solutions with modified Chebyshev-Picard iteration is about an order of magnitude faster compared with the classical shooting method and a tenth-twelfth order Runge-Kutta integrator. It is well known that the solution to Lambert's problem over multiple revolutions is not unique and to ensure that all possible solutions are considered we make use of a reliable preexisting Keplerian Lambert solver to warm start our perturbed algorithm.

  8. The extended hyperbolic function method and exact solutions of the long-short wave resonance equations

    International Nuclear Information System (INIS)

    Shang Yadong

    2008-01-01

    The extended hyperbolic functions method for nonlinear wave equations is presented. Based on this method, we obtain a multiple exact explicit solutions for the nonlinear evolution equations which describe the resonance interaction between the long wave and the short wave. The solutions obtained in this paper include (a) the solitary wave solutions of bell-type for S and L, (b) the solitary wave solutions of kink-type for S and bell-type for L, (c) the solitary wave solutions of a compound of the bell-type and the kink-type for S and L, (d) the singular travelling wave solutions, (e) periodic travelling wave solutions of triangle function types, and solitary wave solutions of rational function types. The variety of structure to the exact solutions of the long-short wave equation is illustrated. The methods presented here can also be used to obtain exact solutions of nonlinear wave equations in n dimensions

  9. Application of a rapid screening method to detect irradiated meat in Brazil

    International Nuclear Information System (INIS)

    Villavicencio, A.L.C.H.; Delincee, H.

    1998-01-01

    Complete text of publication follows. Based on the enormous potential for food irradiation in Brazil, and to ensure free consumer choice, there is a need to find a convenient and rapid method for detection of irradiated food. Since treatment with ionizing radiation causes DNA fragmentation, the analysis of DNA damage might be promising. In fact, DNA fragmentation measured in single cells by agarose gel electrophoresis - DNA Comet Assay - has shown to offer great potential as a rapid tool to detect whether a wide variety of foodstuffs has been radiation processed. However, more work is needed to exploit the full potential of this promising technique. In this paper, the DNA Comet Assay was used to identify exotic meat (boar, jacare and capybara), irradiated with 60 Co gamma-rays. The applied radiation doses were 0, 1.5, 3.0 and 4.5 kGy. Analysis of the DNA migration enable a rapid identification of the radiation treatment

  10. Evaluation of time-accelerated irradiation method of elastomer by modulus-ultimate elongation profile

    International Nuclear Information System (INIS)

    Ito, Masayuki; Oka, Toshitaka; Hama, Yosimasa

    2009-01-01

    'Generalized modulus-ultimate elongation profile' was induced from the relationship between the modulus and the ultimate elongation of an elastomer that was quantitatively added crosslinking and scission. This profile can be used to evaluate the time-accelerated irradiation methods of ethylene-propylene-diene elastomer. The irradiation under low dose rate (0.33 kGy/h) at room temperature was the reference condition. The short-time irradiation condition was 4.2 kGy/h in 0.5 MPa oxygen at room temperature and 5.0 kGy/h in air at 70 o C. The former tended to bring about the higher ratio of scission than the reference condition; the latter tended to bring about the higher ratio of crosslinking.

  11. Studies on bone marrow damages after 60Co irradiation using uncalcified method

    International Nuclear Information System (INIS)

    Yamada, Mitsuaki

    1976-01-01

    Acute bone marrow degeneration and early regeneration after local 60 Co irradiation to rat bone marrow were studied histologically with the use of a ''Cut-all microtome''. With the use of Epon embedding, this method makes it possible to observe bone marrow in the natural state, especially to observe sinusoidal and stromal changes. After 60 Co irradiation of 500 and 1000 r to rat bone marrow, degeneration and disappearance of hematopoietic elements of the erythropoietic and granulopoietic series were noted within three days. In the hematopoietic elements of the megakaryocytic series, after 60 Co irradiation of 500 r, only mild changes were found, but after 60 Co irradiation of 1000 r, significant changes were noted. Sinusoidal and stromal reaction was also noted. Hematopoietic depression and regeneration were correlated with the disappearance and regeneration of the sinusoidal microcirculation. Against the previous reports, in the non-irradiated bone marrow, mild degeneration of the sinusoid was noted. In this study, associated with the degeneration of sinusoid -dilatation of the sinusoid and exudation-, disappearance of hematopoietic cells was noted. The etiology of the above fact is not know at present. (Evans, J.)

  12. Radiolytic degradation and toxicity changes in {gamma}-irradiated solutions of 2,4-dichlorophenol

    Energy Technology Data Exchange (ETDEWEB)

    Trojanowicz, M. E-mail: trojan@chem.uw.edu.pl; Drzewicz, P.; Panta, P.; Gluszewski, W.; Nalcz-Jawecki, G.; Sawicki, J.; Sampa, M.H.O.; Oikawa, H.; Borrely, S.I.; Czaplicka, M.; Szewczynska, M

    2002-11-01

    Preliminary investigations of a petroleum industry wastes with high concentrations of phenols and chlorophenols have shown that irradiation with electron beam results in the efficient destruction of specific organic compounds. In this study the degradation of 2,4-dichlorophenol (2,4-DCP) was studied using a {sup 60}Co gamma source. The determination of reaction by-products was carried out with HPLC, ion chromatography with various detectors, GC/MS and total organic carbon analyzer. The toxicity was measured with bioluminescence test Microtox[reg]. Studies of products of 2,4-DCP radiolysis at initial concentration level 20-50 mg/l have shown that with increased radiation dose degradation proceeds with a stepwise dehalogenation, through the formation of dihydroxybenzenes followed by the formation of non-aromatic carboxylic acids. The transient formation of dihydroxybenzenes resulted in an increase in toxicity at low doses up to 1 kGy. Even at a dose of 20 kGy, not more than about 20% mineralization was observed. The efficiency and mechanism of 2,4-DCP degradation is affected by the presence of scavengers of hydroxyl radical and hydrated electrons such as nitrate or bicarbonate.

  13. Formation of inorganic nitrogenous byproducts in aqueous solution under ultrasound irradiation.

    Science.gov (United States)

    Yao, Juanjuan; Chen, Longfu; Chen, Xiangyu; Zhou, Lingxi; Liu, Wei; Zhang, Zhi

    2018-04-01

    The effects of ultrasonic frequency, power intensity, temperature and sparged gas on the generation of nitrogenous by-products NO 2 - and NO 3 - have been investigated, and the new kinetics model of NO 2 - and NO 3 - generation was also explored. The results show that the highest primary generation rate of NO 2 - and NO 3 - by direct sonolysis in the cavitation bubbles (represented by k 1 ' and k 2 ', respectively) was obtained at 600 kHz and 200 kHz, respectively, in the applied ultrasonic frequency range of 200 to 800 kHz. The primary generation rate of NO 2 - (represented by k 1 ') increased with the increasing ultrasonic intensity while the primary generation rate of NO 3 - (represented by k 2 ') decreased. The lower temperature is beneficial to the primary generation of both NO 2 - and NO 3 - in the cavitation bubbles. The optimal overall yields of both NO 2 - and NO 3 - were obtained at the N 2 /O 2 volume (in the sparged gas) ratio of 3:1 which is near to the ratio of N 2 /O 2 in air. The dissolved O 2 is the dominant oxygen element source for both NO and NO 2 , compared with water vapor. Ultrasonic irradiation can significant enhance the recovery rates of dissolved N 2 and O 2 and thus keep the N 2 fixation reaction going even without aeration. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Molecular dynamics study of interstitial-solute interactions in irradiated alloys

    International Nuclear Information System (INIS)

    Lam, N.Q.; Doan, N.V.; Adda, Y.

    1980-01-01

    The molecular dynamics technique has been used, in conjunction with the interionic potentials of Dagens et al, to study the stability, configuration, binding, and induced migration of mixed dumbbells in an irradiated Al-Zn alloy. For the purpose of comparisons, self-interstitials in pure Al were also investigated. The Al-Al and Al-Zn interactions were described by pair potentials which extended to ninth-neighbour distances. Both the self-interstitial dumbbell and the mixed dumbbell were found to be stable in the configuration. The formation energy of the self-interstitial is 2.89 eV and the mixed-dumbbell binding energy is 0.38 eV. As a result of this strong binding, the threshold energy required to induce the migration of the mixed dumbbell is about 1.2 eV, which is significantly larger than the minimum energy of about 0.15 eV transferred to a self-interstitial to induce its jumps in pure Al. Caging motions of the mixed dumbbell were observed. The present computer-simulation results are compared with experimental measurements. (author)

  15. Soliton-like solutions to the GKdV equation by extended mapping method

    International Nuclear Information System (INIS)

    Wu Ranchao; Sun Jianhua

    2007-01-01

    In this note, many new exact solutions of the generalized KdV equation, such as rational solutions, periodic solutions like Jacobian elliptic and triangular functions, soliton-like solutions, are constructed by symbolic computation and the extended mapping method, with the auxiliary ordinary equation replaced by a more general one

  16. Multiple travelling wave solutions of nonlinear evolution equations using a unified algebraic method

    International Nuclear Information System (INIS)

    Fan Engui

    2002-01-01

    A new direct and unified algebraic method for constructing multiple travelling wave solutions of general nonlinear evolution equations is presented and implemented in a computer algebraic system. Compared with most of the existing tanh methods, the Jacobi elliptic function method or other sophisticated methods, the proposed method not only gives new and more general solutions, but also provides a guideline to classify the various types of the travelling wave solutions according to the values of some parameters. The solutions obtained in this paper include (a) kink-shaped and bell-shaped soliton solutions, (b) rational solutions, (c) triangular periodic solutions and (d) Jacobi and Weierstrass doubly periodic wave solutions. Among them, the Jacobi elliptic periodic wave solutions exactly degenerate to the soliton solutions at a certain limit condition. The efficiency of the method can be demonstrated on a large variety of nonlinear evolution equations such as those considered in this paper, KdV-MKdV, Ito's fifth MKdV, Hirota, Nizhnik-Novikov-Veselov, Broer-Kaup, generalized coupled Hirota-Satsuma, coupled Schroedinger-KdV, (2+1)-dimensional dispersive long wave, (2+1)-dimensional Davey-Stewartson equations. In addition, as an illustrative sample, the properties of the soliton solutions and Jacobi doubly periodic solutions for the Hirota equation are shown by some figures. The links among our proposed method, the tanh method, extended tanh method and the Jacobi elliptic function method are clarified generally. (author)

  17. Elliptic equation rational expansion method and new exact travelling solutions for Whitham-Broer-Kaup equations

    International Nuclear Information System (INIS)

    Chen Yong; Wang Qi; Li Biao

    2005-01-01

    Based on a new general ansatz and a general subepuation, a new general algebraic method named elliptic equation rational expansion method is devised for constructing multiple travelling wave solutions in terms of rational special function for nonlinear evolution equations (NEEs). We apply the proposed method to solve Whitham-Broer-Kaup equation and explicitly construct a series of exact solutions which include rational form solitary wave solution, rational form triangular periodic wave solutions and rational wave solutions as special cases. In addition, the links among our proposed method with the method by Fan [Chaos, Solitons and Fractals 2004;20:609], are also clarified generally

  18. Ultraviolet-C Irradiation: A Novel Pasteurization Method for Donor Human Milk.

    Science.gov (United States)

    Christen, Lukas; Lai, Ching Tat; Hartmann, Ben; Hartmann, Peter E; Geddes, Donna T

    2013-01-01

    Holder pasteurization (milk held at 62.5°C for 30 minutes) is the standard treatment method for donor human milk. Although this method of pasteurization is able to inactivate most bacteria, it also inactivates important bioactive components. Therefore, the objective of this study was to investigate ultraviolet irradiation as an alternative treatment method for donor human milk. Human milk samples were inoculated with five species of bacteria and then UV-C irradiated. Untreated and treated samples were analysed for bacterial content, bile salt stimulated lipase (BSSL) activity, alkaline phosphatase (ALP) activity, and fatty acid profile. All five species of bacteria reacted similarly to UV-C irradiation, with higher dosages being required with increasing concentrations of total solids in the human milk sample. The decimal reduction dosage was 289±17 and 945±164 J/l for total solids of 107 and 146 g/l, respectively. No significant changes in the fatty acid profile, BSSL activity or ALP activity were observed up to the dosage required for a 5-log10 reduction of the five species of bacteria. UV-C irradiation is capable of reducing vegetative bacteria in human milk to the requirements of milk bank guidelines with no loss of BSSL and ALP activity and no change of FA.

  19. Methods of Uranium Determination in solutions of Tributyl Phosphate and Kerosene

    International Nuclear Information System (INIS)

    Petrement Eguiluz, J.; Palomares Delgado, F.

    1962-01-01

    A new analytical method for the determination of uranium in organic solutions of tributyl phosphate and kerosene is proposed. In this method the uranium is reextracted from the aqueous phase by reduction with cadmium in acid solution. The uranium can be determined in this solution by the usual methods. In case of very diluted solutions, a direct spectrophtometrical determination of uranium in the organic phase with dibenzoylmethane is proposed. (Author) 21 refs

  20. An Algebraic Method for Constructing Exact Solutions to Difference-Differential Equations

    International Nuclear Information System (INIS)

    Wang Zhen; Zhang Hongqing

    2006-01-01

    In this paper, we present a method to solve difference differential equation(s). As an example, we apply this method to discrete KdV equation and Ablowitz-Ladik lattice equation. As a result, many exact solutions are obtained with the help of Maple including soliton solutions presented by hyperbolic functions sinh and cosh, periodic solutions presented by sin and cos and rational solutions. This method can also be used to other nonlinear difference-differential equation(s).

  1. Method of precipitating uranium from an aqueous solution and/or sediment

    Science.gov (United States)

    Tokunaga, Tetsu K; Kim, Yongman; Wan, Jiamin

    2013-08-20

    A method for precipitating uranium from an aqueous solution and/or sediment comprising uranium and/or vanadium is presented. The method includes precipitating uranium as a uranyl vanadate through mixing an aqueous solution and/or sediment comprising uranium and/or vanadium and a solution comprising a monovalent or divalent cation to form the corresponding cation uranyl vanadate precipitate. The method also provides a pathway for extraction of uranium and vanadium from an aqueous solution and/or sediment.

  2. Study on irradiation sterilization of medical gauze pad by incremental dosage method

    International Nuclear Information System (INIS)

    Lei Qing; Huang Min; Deng Wenmin; Wu Ling; Wang Yan; Gao Peng; Du Xiaoying; Xie Yan

    2011-01-01

    To explore the sterilization dose setting method for medical products, the irradiation sterilization dose for medical products was set according to the method 2A of international standard ISO11137 Part 2. The verification dose for medical gauze pad by was set by incremental dose method and with a series of formula. Then the sterilization dose for an SAL of 10 -6 was established by completing the verification dose experiment. The final sterilization dose for medical gauze pad was decided to be 29.7 kGy. This study gives reference for the setting irradiation sterilization dose for medical products which need to adopt the method 2A of international standard ISO11137 Part 2. (authors)

  3. Extraction and identification of cyclobutanones from irradiated cheese employing a rapid direct solvent extraction method.

    Science.gov (United States)

    Tewfik, Ihab

    2008-01-01

    2-Alkylcyclobutanones (cyclobutanones) are accepted as chemical markers for irradiated foods containing lipid. However, current extraction procedures (Soxhlet-florisil chromatography) for the isolation of these markers involve a long and tedious clean-up regime prior to gas chromatography-mass spectrophotometry identification. This paper outlines an alternative isolation and clean-up method for the extraction of cyclobutanones in irradiated Camembert cheese. The newly developed direct solvent extraction method enables the efficient screening of large numbers of food samples and is not as resource intensive as the BS EN 1785:1997 method. Direct solvent extraction appears to be a simple, robust method and has the added advantage of a considerably shorter extraction time for the analysis of foods containing lipid.

  4. Effect of hydrocarbon chain length of aliphatic diluents on hydrodynamic properties of irradiated solutions of extractant

    International Nuclear Information System (INIS)

    Gumenyuk, V.E.; Pribush, A.G.; Egorov, G.F.

    1990-01-01

    To optimize the composition of n-paraffin mixtures with different molecular weight, used as a diluent (D) of extractant during extraction reprocessing of spent fuel, interrelation between D hydrocarbon chain length and change in hydrodynamic properties of extraction mixture on D basis depending on the dose has been considered. It is shown that the value of threshold dose loading (D crit ), at which a sharp change in hydrodynamic properties of tri-n-butyl phosphate solutions in D is observed, decreases with hydrocarbon chain length growth. Empiric ratio relating D crit value and the number of carbon atoms of D is obtained

  5. Method for Non-Invasive Determination of Chemical Properties of Aqueous Solutions

    Science.gov (United States)

    Todd, Paul W. (Inventor); Jones, Alan (Inventor); Thomas, Nathan A. (Inventor)

    2016-01-01

    A method for non-invasively determining a chemical property of an aqueous solution is provided. The method provides the steps of providing a colored solute having a light absorbance spectrum and transmitting light through the colored solute at two different wavelengths. The method further provides the steps of measuring light absorbance of the colored solute at the two different transmitted light wavelengths, and comparing the light absorbance of the colored solute at the two different wavelengths to determine a chemical property of an aqueous solution.

  6. A stochastic post-processing method for solar irradiance forecasts derived from NWPs models

    Science.gov (United States)

    Lara-Fanego, V.; Pozo-Vazquez, D.; Ruiz-Arias, J. A.; Santos-Alamillos, F. J.; Tovar-Pescador, J.

    2010-09-01

    Solar irradiance forecast is an important area of research for the future of the solar-based renewable energy systems. Numerical Weather Prediction models (NWPs) have proved to be a valuable tool for solar irradiance forecasting with lead time up to a few days. Nevertheless, these models show low skill in forecasting the solar irradiance under cloudy conditions. Additionally, climatic (averaged over seasons) aerosol loading are usually considered in these models, leading to considerable errors for the Direct Normal Irradiance (DNI) forecasts during high aerosols load conditions. In this work we propose a post-processing method for the Global Irradiance (GHI) and DNI forecasts derived from NWPs. Particularly, the methods is based on the use of Autoregressive Moving Average with External Explanatory Variables (ARMAX) stochastic models. These models are applied to the residuals of the NWPs forecasts and uses as external variables the measured cloud fraction and aerosol loading of the day previous to the forecast. The method is evaluated for a set one-moth length three-days-ahead forecast of the GHI and DNI, obtained based on the WRF mesoscale atmospheric model, for several locations in Andalusia (Southern Spain). The Cloud fraction is derived from MSG satellite estimates and the aerosol loading from the MODIS platform estimates. Both sources of information are readily available at the time of the forecast. Results showed a considerable improvement of the forecasting skill of the WRF model using the proposed post-processing method. Particularly, relative improvement (in terms of the RMSE) for the DNI during summer is about 20%. A similar value is obtained for the GHI during the winter.

  7. Construct solitary solutions of discrete hybrid equation by Adomian Decomposition Method

    International Nuclear Information System (INIS)

    Wang Zhen; Zhang Hongqing

    2009-01-01

    In this paper, we apply the Adomian Decomposition Method to solving the differential-difference equations. A typical example is applied to illustrate the validity and the great potential of the Adomian Decomposition Method in solving differential-difference equation. Kink shaped solitary solution and Bell shaped solitary solution are presented. Comparisons are made between the results of the proposed method and exact solutions. The results show that the Adomian Decomposition Method is an attractive method in solving the differential-difference equations.

  8. Radiolysis of benzyl alcohol in aqueous solution by external gamma-irradiation

    International Nuclear Information System (INIS)

    Ikebuchi, Hideharu; Kido, Yasumasa; Urakubo, Goro

    1977-01-01

    Radiolysis of 0.05% aqueous solution of benzyl alcohol with 60 Co γ-rays ranging from 1 x 10 4 to 7 x 10 5 rad was investigated, in order to presume the change of it contained in radiopharmaceuticals. For both O 2 free and oxygenated solutions, an approximately linear relationship holds between the retaining benzyl alcohol and dose in the range from 1 x 10 5 to 7 x 10 5 rads. The G(-M) values of benzyl alcohol calculated from the relation were 2.34 in the absence and 1.92 in presence of oxygen. In the presence of oxygen, a main product was benzaldehyde and its G value was 0.87. In the absence of oxygen, the main products of the radiolysis were dibenzyl, benzyl phenylcalbinol and hydrobenzoin, which were regarded as the radical-reaction products of PhCH 2 and PhCHOH, and the yield of benzaldehyde was negligible. Irrespective of the presence of oxygen, o- and p-hydroxylated products of benzyl alcohol were found only in small quantity. (auth.)

  9. Modified harmonic balance method for the solution of nonlinear jerk equations

    Science.gov (United States)

    Rahman, M. Saifur; Hasan, A. S. M. Z.

    2018-03-01

    In this paper, a second approximate solution of nonlinear jerk equations (third order differential equation) can be obtained by using modified harmonic balance method. The method is simpler and easier to carry out the solution of nonlinear differential equations due to less number of nonlinear equations are required to solve than the classical harmonic balance method. The results obtained from this method are compared with those obtained from the other existing analytical methods that are available in the literature and the numerical method. The solution shows a good agreement with the numerical solution as well as the analytical methods of the available literature.

  10. Further improved F-expansion method and new exact solutions of Konopelchenko-Dubrovsky equation

    International Nuclear Information System (INIS)

    Wang Dengshan; Zhang Hongqing

    2005-01-01

    In this paper, with the aid of the symbolic computation we improve the extended F-expansion method in [Chaos, Solitons and Fractals 2004; 22:111] and propose the further improved F-expansion method. Using this method, we have gotten many new exact solutions which we have never seen before within our knowledge of the (2 + 1)-dimensional Konopelchenko-Dubrovsky equation. In addition,the solutions we get are more general than the solutions that the extended F-expansion method gets.The solutions we get include Jacobi elliptic function solutions, soliton-like solutions, trigonometric function solutions and so on. Our method can also apply to other partial differential equations and can also get many new exact solutions

  11. A Method to Simulate the Observed Surface Properties of Proton Irradiated Silicon Strip Sensors

    CERN Document Server

    Peltola, Timo Hannu Tapani

    2014-01-01

    A defect model of Synopsys Sentaurus TCAD simulation package for the bulk properties of proton irradiated devices has been producing simulations closely matching to measurements of silicon strip detectors. However, the model does not provide the expected behavior due to the fluence increased surface damage. The solution requires an approach that does not affect the accurate bulk properties produced by the proton model, but only adds to it the required radiation induced properties close to the surface. These include the observed position dependency of the strip detector's...

  12. An attempt of 'out-tongue method' to reduce taste dysfunction following head and neck irradiation

    International Nuclear Information System (INIS)

    Miyashita, Tsuguhiro; Tateno, Atsushi; Kumashiro, Katsutoshi; Sasaki, Sadayuki; Kumazaki, Tatsuo; Ohno, Haruyoshi; Sato, Iisaku.

    1996-01-01

    To reduce taste dysfunction which lowers QOL of patients with head and neck carcinoma during and after radiation therapy, an 'out-tongue method' was attempted where patients put out their tongue during the irradiation. The attempt was done on 15 patients of the carcinoma, aging 42-83 years old. They received enough information and training of the method. The training was important for reproducibility. Irradiation with 35-61.2 (mean 52.9) Gy of the oral cavity was performed by linac with continuous monitoring for keeping the method. The volume of irradiated tongue was reduced to 1/3-2/3 level. The effect of the method was evaluated by 4-graded score: no change, fair (a small change in taste post radiation), moderate and severe (no taste). The method gave no change in 9 patients (60%), fair in 3 (20%), moderate in 3 (20%) and severe in 0 (0%). These results suggested that this method was useful. (K.H.)

  13. Two-faces stationary irradiation method and dosimetric considerations for radiation processing at the multipurpose gamma irradiation facility / IPEN-CNEN

    International Nuclear Information System (INIS)

    Santos, Paulo S.; Vasquez, Pablo A.S.

    2015-01-01

    Over the last ten years, the Multipurpose Gamma Irradiation Facility of the Nuclear and Energy Research Institute - IPEN/CNEN located inside the Sao Paulo University campus has been providing services on radiation processing, especially for sterilization of health care and disposable medical products as well as support to research studies on modification of physical, chemical and biological properties of several materials. Placed at the same campus operates an extremely important radiopharmaceutical production facility when almost all disposable supplies used to produce medical products as the technetium-99m are continuously sterilized by gamma radiation. Many university biomedical research laboratories specially those working with equipment for cell cultures and vaccine production also make use of the gamma sterilization. Animal feed and shavings used by certified bioteries are routinely disinfected. Alternative underwater irradiation methods were developed to meet the demand of gemstone color enhancement. Human tissues including bone, skin, amniotic membranes, tendons, and cartilage belonging to National Banks are usually irradiated too. Different kind of polymers, hydrogels, foods as well native fruits, have been irradiated in this facility. Cultural heritage objects as books, paintings and furniture are disinfected routinely by gamma radiation. The success of the implementation of radiation processing in this facility is due to research and development of irradiation and dosimetry methods suitable for each condition. In this work are presented some considerations about the distribution dose and the two-faces stationary irradiation method developed and validated for this facility. (author)

  14. Two-faces stationary irradiation method and dosimetric considerations for radiation processing at the multipurpose gamma irradiation facility / IPEN-CNEN

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Paulo S.; Vasquez, Pablo A.S., E-mail: psantos@ipen.br, E-mail: pavsalva@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Over the last ten years, the Multipurpose Gamma Irradiation Facility of the Nuclear and Energy Research Institute - IPEN/CNEN located inside the Sao Paulo University campus has been providing services on radiation processing, especially for sterilization of health care and disposable medical products as well as support to research studies on modification of physical, chemical and biological properties of several materials. Placed at the same campus operates an extremely important radiopharmaceutical production facility when almost all disposable supplies used to produce medical products as the technetium-99m are continuously sterilized by gamma radiation. Many university biomedical research laboratories specially those working with equipment for cell cultures and vaccine production also make use of the gamma sterilization. Animal feed and shavings used by certified bioteries are routinely disinfected. Alternative underwater irradiation methods were developed to meet the demand of gemstone color enhancement. Human tissues including bone, skin, amniotic membranes, tendons, and cartilage belonging to National Banks are usually irradiated too. Different kind of polymers, hydrogels, foods as well native fruits, have been irradiated in this facility. Cultural heritage objects as books, paintings and furniture are disinfected routinely by gamma radiation. The success of the implementation of radiation processing in this facility is due to research and development of irradiation and dosimetry methods suitable for each condition. In this work are presented some considerations about the distribution dose and the two-faces stationary irradiation method developed and validated for this facility. (author)

  15. Formic acid enhanced effective degradation of methyl orange dye in aqueous solutions under UV-Vis irradiation.

    Science.gov (United States)

    Wang, Jingjing; Bai, Renbi

    2016-09-15

    Developing efficient technologies to treat recalcitrant organic dye wastewater has long been of great research and practical interest. In this study, a small molecule, formic acid (FA), was applied as a process enhancer for the degradation of methyl orange (MO) dye as a model recalcitrant organic pollutant in aqueous solutions under the condition of UV-Vis light irradiation and air aeration at the ambient temperature of 25 °C. It was found that the decolouration of the dye solutions can be rapidly achieved, reducing the time, for example, from around 17.6 h without FA to mostly about less than 2 h with the presence of FA. The mineralization rate of MO dye reached as high as 81.8% in 1.5 h in the case of initial MO dye concentration at 25 mg L(-1), which is in contrast to nearly no mineralization of the MO dye for a similar system without the FA added. The study revealed that the generation of the H2O2 species in the system was enhanced and the produced OH radicals effectively contributed to the degradation of the MO dye. Process parameters such as the initial concentration of MO dye, FA dosage and solution pH were all found to have some effect on the degradation efficiency under the same condition of UV-Vis light irradiation and air aeration. The MO dye degradation performance was found to follow a first-order reaction rate to the MO dye concentration in most cases and there existed a positive correlation between the reaction rate constant and the initial FA concentration. Compared to the traditional H2O2/UV-Vis oxidation system, the use of FA as a process-enhancing agent can have the advantages of low cost, easy availability, and safe to use. The study hence demonstrates a promising approach to use a readily available small molecule of FA to enhance the degradation of recalcitrant organic pollutants, such as MO dye, especially for their pre-treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Substep methods for burnup calculations with Bateman solutions

    International Nuclear Information System (INIS)

    Isotalo, A.E.; Aarnio, P.A.

    2011-01-01

    Highlights: → Bateman solution based depletion requires constant microscopic reaction rates. → Traditionally constant approximation is used for each depletion step. → Here depletion steps are divided to substeps which are solved sequentially. → This allows piecewise constant, rather than constant, approximation for each step. → Discretization errors are almost completely removed with only minor slowdown. - Abstract: When material changes in burnup calculations are solved by evaluating an explicit solution to the Bateman equations with constant microscopic reaction rates, one has to first predict the development of the reaction rates during the step and then further approximate these predictions with their averages in the depletion calculation. Representing the continuously changing reaction rates with their averages results in some error regardless of how accurately their development was predicted. Since neutronics solutions tend to be computationally expensive, steps in typical calculations are long and the resulting discretization errors significant. In this paper we present a simple solution to reducing these errors: the depletion steps are divided to substeps that are solved sequentially, allowing finer discretization of the reaction rates without additional neutronics solutions. This greatly reduces the discretization errors and, at least when combined with Monte Carlo neutronics, causes only minor slowdown as neutronics dominates the total running time.

  17. Solutions of differential equations with regular coefficients by the methods of Richmond and Runge-Kutta

    Science.gov (United States)

    Cockrell, C. R.

    1989-01-01

    Numerical solutions of the differential equation which describe the electric field within an inhomogeneous layer of permittivity, upon which a perpendicularly-polarized plane wave is incident, are considered. Richmond's method and the Runge-Kutta method are compared for linear and exponential profiles of permittivities. These two approximate solutions are also compared with the exact solutions.

  18. Generation of new solutions of the stationary axisymmetric Einstein equations by a double complex function method

    International Nuclear Information System (INIS)

    Zhong, Z.

    1985-01-01

    A new approach to the solution of certain differential equations, the double complex function method, is developed, combining ordinary complex numbers and hyperbolic complex numbers. This method is applied to the theory of stationary axisymmetric Einstein equations in general relativity. A family of exact double solutions, double transformation groups, and n-soliton double solutions are obtained

  19. Fundamental solution of the problem of linear programming and method of its determination

    Science.gov (United States)

    Petrunin, S. V.

    1978-01-01

    The idea of a fundamental solution to a problem in linear programming is introduced. A method of determining the fundamental solution and of applying this method to the solution of a problem in linear programming is proposed. Numerical examples are cited.

  20. A direct algebraic method applied to obtain complex solutions of some nonlinear partial differential equations

    International Nuclear Information System (INIS)

    Zhang Huiqun

    2009-01-01

    By using some exact solutions of an auxiliary ordinary differential equation, a direct algebraic method is described to construct the exact complex solutions for nonlinear partial differential equations. The method is implemented for the NLS equation, a new Hamiltonian amplitude equation, the coupled Schrodinger-KdV equations and the Hirota-Maccari equations. New exact complex solutions are obtained.

  1. The modified simplest equation method to look for exact solutions of nonlinear partial differential equations

    OpenAIRE

    Efimova, Olga Yu.

    2010-01-01

    The modification of simplest equation method to look for exact solutions of nonlinear partial differential equations is presented. Using this method we obtain exact solutions of generalized Korteweg-de Vries equation with cubic source and exact solutions of third-order Kudryashov-Sinelshchikov equation describing nonlinear waves in liquids with gas bubbles.

  2. Food irradiation

    International Nuclear Information System (INIS)

    Lindqvist, H.

    1996-01-01

    This paper is a review of food irradiation and lists plants for food irradiation in the world. Possible applications for irradiation are discussed, and changes induced in food from radiation, nutritional as well as organoleptic, are reviewed. Possible toxicological risks with irradiated food and risks from alternative methods for treatment are also brought up. Ways to analyze weather food has been irradiated or not are presented. 8 refs

  3. A dielectric method for measuring early and late reactions in irradiated human skin

    International Nuclear Information System (INIS)

    Nuutinen, J.; Lahtinen, T.; Turunen, M.; Alanen, E.; Tenhunen, M.; Usenius, T.; Kolle, R.

    1998-01-01

    Background and purpose: To measure the dielectric constant of irradiated human skin in order to test the feasibility of the dielectric measurements in the quantitation of acute and late radiation reactions. Materials and methods: The dielectric constant of irradiated breast skin was measured at an electromagnetic frequency of 300 MHz in 21 patients during postmastectomy radiotherapy. The measurements were performed with an open-ended coaxial line reflection method. The irradiation technique consisted of an anterior photon field to the lymph nodes and a matched electron field to the chest wall using conventional fractionation of five fractions/week to 50 Gy. Fourteen out of the 21 patients were remeasured 2 years later and the skin was palpated for subcutaneous fibrosis. Results: At 5 weeks the dielectric constant had decreased by 31 and 39% for the investigated skin sites of the photon and electron fields, respectively. There was a statistically significant inverse correlation between the mean dielectric constant and the clinical score of erythema. An unexpected finding was a decrease of the dielectric constant of the contralateral healthy skin during radiotherapy. Two years later a statistically significant positive correlation was found between the dielectric constant at the irradiated skin sites and the clinical score of subcutaneous fibrosis. Conclusions: Dielectric measurements non-invasively yield quantitative information concerning radiation-induced skin reactions. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Determination of burnup in irradiated nuclear fuels by the method of stable 148Nd fission products

    International Nuclear Information System (INIS)

    Souza Sarkis, J.E. de.

    1982-01-01

    A method is described for the isotopic analysis and determination of burnup in irradiated nuclear fuel by mass spectrometric technique. The burnup is calculed from the determination of the concentration of uranium, plutonium and the fission product 148 Nd in the samples of UO 2 irradiated fuel from a P.W.R. type reactor. The method involves the separation of fractions of uranium, plutonium and neodimium from the dissolved irradiated fuel by ion exchange technique. The determination of uranium, plutonium and the fission product 148 Nd is carried out by isotope diluition mass spectrometry technique using as isotope tracers the nuclides 233 U, 242 Pu and 150 Nd. For the chemical processing and handling of the irradiated sample a Hot Chemistry Laboratory was mounted. It consists of glove boxes and equipments for radiation monitoring and protection. The results obtained indicate an atom percent burnup of 2.181 + - 0.035% wich corresponds an 20.937 + - 0.739 Gwd/ton of thermal energy produced. (Author) [pt

  5. Formation of tryptophan radicals in irradiated aqueous solutions of hexachloroplatinate(IV): a flash photolysis study.

    Science.gov (United States)

    Zang, L; Rodgers, M A

    1999-10-01

    The oxidation of tryptophan photosensitized by PtCl6(2-) has been investigated in aqueous solutions at different pH using nanosecond laser flash photolysis. Cationic and neutral radicals of tryptophan were detected at pH 2.8 and 8.5, respectively. The generation of the radical was attributed to oxidation by Cl2- that was formed from the homolytic bond cleavage in the excited state of PtCl6(2-). The bimolecular rate constant derived from the kinetics analysis, 2.8 +/- 0.2 x 10(9) M-1 s-1, is in good agreement with the value obtained in earlier pulse radiolysis studies. Both the cationic and neutral radicals decayed by second-order kinetics, consistent with the dimerization process.

  6. Waste Treatment of Acidic Solutions from the Dissolution of Irradiated LEU Targets for 99-Mo Production

    Energy Technology Data Exchange (ETDEWEB)

    Bakel, Allen J. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Conner, Cliff [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2016-10-01

    One of the missions of the Reduced Enrichment for Research and Test Reactors (RERTR) program (and now the National Nuclear Security Administrations Material Management and Minimization program) is to facilitate the use of low enriched uranium (LEU) targets for 99Mo production. The conversion from highly enriched uranium (HEU) to LEU targets will require five to six times more uranium to produce an equivalent amount of 99Mo. The work discussed here addresses the technical challenges encountered in the treatment of uranyl nitrate hexahydrate (UNH)/nitric acid solutions remaining after the dissolution of LEU targets. Specifically, the focus of this work is the calcination of the uranium waste from 99Mo production using LEU foil targets and the Modified Cintichem Process. Work with our calciner system showed that high furnace temperature, a large vent tube, and a mechanical shield are beneficial for calciner operation. One- and two-step direct calcination processes were evaluated. The high-temperature one-step process led to contamination of the calciner system. The two-step direct calcination process operated stably and resulted in a relatively large amount of material in the calciner cup. Chemically assisted calcination using peroxide was rejected for further work due to the difficulty in handling the products. Chemically assisted calcination using formic acid was rejected due to unstable operation. Chemically assisted calcination using oxalic acid was recommended, although a better understanding of its chemistry is needed. Overall, this work showed that the two-step direct calcination and the in-cup oxalic acid processes are the best approaches for the treatment of the UNH/nitric acid waste solutions remaining from dissolution of LEU targets for 99Mo production.

  7. Radioactivity measurements of 32P solutions by calorimetric methods

    International Nuclear Information System (INIS)

    Genka, T.; Nataredja, I.K.

    1992-01-01

    Radioactivity of 32 P solution is measured with a twin-cup heat-flow microcalorimeter. In order to convert whole decay energy evolved from the 32 P solution in a glass vial into thermal power, 5 mm-thick lead container was used as a radiation absorber. Corrections for heat loss due to thermal radiation and bremsstrahlung escape as well as an effect of impurity ( 33 P) are conducted. The overall uncertainty of the nondestructive measurement as a sample is in a container is estimated to be ± 1.5 %. Discussion about estimates of uncertainties is also given in detail. (author)

  8. Numerical soliton-like solutions of the potential Kadomtsev-Petviashvili equation by the decomposition method

    International Nuclear Information System (INIS)

    Kaya, Dogan; El-Sayed, Salah M.

    2003-01-01

    In this Letter we present an Adomian's decomposition method (shortly ADM) for obtaining the numerical soliton-like solutions of the potential Kadomtsev-Petviashvili (shortly PKP) equation. We will prove the convergence of the ADM. We obtain the exact and numerical solitary-wave solutions of the PKP equation for certain initial conditions. Then ADM yields the analytic approximate solution with fast convergence rate and high accuracy through previous works. The numerical solutions are compared with the known analytical solutions

  9. CdSe nanoparticles grown via radiolytic methods in aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Shalini [Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Rath, M.C., E-mail: madhab@barc.gov.i [Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Singh, A.K. [Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Mukherjee, T. [Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Jayakumar, O.D.; Tyagi, A.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Sarkar, S.K. [Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

    2011-06-15

    Cadmium selenide, CdSe, nanoparticles have been synthesized in aqueous solution containing equimolar ammoniated CdSO{sub 4} and Na{sub 2}SeSO{sub 3} as the starting materials without any capping agents, using gamma and electron beam irradiation under a reducing condition. The radiolytic processes occurring in water result in the formation of CdSe nanoparticles through the reactions mediated by hydrated electrons, e{sub aq}{sup -}. TEM measurements revealed that the CdSe nanoparticles were found to exist in agglomerates of dimension of about 100 nm, consisting of primary nanoparticles of dimensions within 5 nm. The as-grown nanoparticles were of cubic crystalline phase as supported by the XRD measurements. These bare CdSe nanoparticles exhibit room temperature ferromagnetic (RTFM) behavior. However, the RTFM behavior was found to be 30% higher in the case of CdSe nanoparticles prepared on electron beam irradiation as compared to those obtained by gamma irradiation, which was attributed to their relatively smaller size (2-3 nm) and disordered structures as compared to those obtained in the later case (3-5 nm). -- Research highlights: {yields} CdSe nanoparticles could be synthesized in aqueous solutions containing equimolar ammoniated CdSO{sub 4} and Na{sub 2}SeSO{sub 3} as the starting materials using gamma and electron beam irradiation under a reducing condition. {yields} CdSe nanoparticles were found to exist in agglomerates of dimension of about 100 nm, consisting of primary nanoparticles of dimensions within 5 nm. {yields} CdSe nanoparticles exhibit room temperature ferromagnetic (RTFM) behavior. {yields} The RTFM behavior was found to be 30% higher in the case of CdSe nanoparticles prepared on electron beam irradiation as compared to those obtained by gamma irradiation.

  10. CdSe nanoparticles grown via radiolytic methods in aqueous solutions

    International Nuclear Information System (INIS)

    Singh, Shalini; Rath, M.C.; Singh, A.K.; Mukherjee, T.; Jayakumar, O.D.; Tyagi, A.K.; Sarkar, S.K.

    2011-01-01

    Cadmium selenide, CdSe, nanoparticles have been synthesized in aqueous solution containing equimolar ammoniated CdSO 4 and Na 2 SeSO 3 as the starting materials without any capping agents, using gamma and electron beam irradiation under a reducing condition. The radiolytic processes occurring in water result in the formation of CdSe nanoparticles through the reactions mediated by hydrated electrons, e aq - . TEM measurements revealed that the CdSe nanoparticles were found to exist in agglomerates of dimension of about 100 nm, consisting of primary nanoparticles of dimensions within 5 nm. The as-grown nanoparticles were of cubic crystalline phase as supported by the XRD measurements. These bare CdSe nanoparticles exhibit room temperature ferromagnetic (RTFM) behavior. However, the RTFM behavior was found to be 30% higher in the case of CdSe nanoparticles prepared on electron beam irradiation as compared to those obtained by gamma irradiation, which was attributed to their relatively smaller size (2-3 nm) and disordered structures as compared to those obtained in the later case (3-5 nm). -- Research highlights: → CdSe nanoparticles could be synthesized in aqueous solutions containing equimolar ammoniated CdSO 4 and Na 2 SeSO 3 as the starting materials using gamma and electron beam irradiation under a reducing condition. → CdSe nanoparticles were found to exist in agglomerates of dimension of about 100 nm, consisting of primary nanoparticles of dimensions within 5 nm. → CdSe nanoparticles exhibit room temperature ferromagnetic (RTFM) behavior. → The RTFM behavior was found to be 30% higher in the case of CdSe nanoparticles prepared on electron beam irradiation as compared to those obtained by gamma irradiation.

  11. Study on gamma-irradiation degradation of chitosan swollen in H2O2 solution and its antimicrobial activity for E. coli

    International Nuclear Information System (INIS)

    Dang Xuan Du; Bui Phuoc Phuc; Tran Thi Thuy; Le Anh Quoc; Dang Van Phu; Nguyen Quoc Hien

    2014-01-01

    Degradation of chitosan in swollen state with hydrogen peroxide solution (5% w/v) by γ-irradiation was investigated. Molecular weight (M w ) of irradiated chitosan was determined by gel permeation chromatography (GPC). Fourier transform infrared (FT-IR) and ultraviolet-visible (UV-vis) spectra were analyzed to study the structure changes of degraded chitosan. The results showed that the chitosan of low M w (30-45 kDa) was efficiently prepared by γ-irradiation of chitosan swollen in hydrogen peroxide solution at low dose less than 20 kGy. The main structure as well as the degree of deacetylation of the degraded chitosan was almost no significant change. Furthermore, the radiation degradation yield (G s ) was remarkably enhanced by the presence of H 2 O 2 . The obtained low M w chitosan revealed high antimicrobial activity for E. coli that can be used for food preservation and other purposes as well. (author)

  12. Long-lived radicals produced by γ-irradiation or vital activity in plants, animals, cells, and protein solution: their observation and inhomogeneous decay dynamics

    International Nuclear Information System (INIS)

    Miyazaki, Tetsuo; Morikawa, Akiyuki; Kumagai, Jun; Ikehata, Masateru; Koana, Takao; Kikuchi, Shoshi

    2002-01-01

    Long-lived radicals produced by γ-irradiation or vital activity in plants, animals, cells, and protein (albumin) solution were studied by electron spin resonance spectroscopy. Long-lived radicals produced by vital activity exist in biological systems, such as plants, animals, and cells, in the range of 0.1-20 nmol g -1 . Since vital organs keep the radicals at a constant concentration, the radicals are probably related to life conservation. Long-lived radicals are also produced by γ-irradiation of cells or protein solution. The radicals decay after death of living things or after γ-irradiation. We found that the decay dynamics in all biological systems can be expressed by the same kinetic equation of an inhomogeneous reaction

  13. A numerical dressing method for the nonlinear superposition of solutions of the KdV equation

    International Nuclear Information System (INIS)

    Trogdon, Thomas; Deconinck, Bernard

    2014-01-01

    In this paper we present the unification of two existing numerical methods for the construction of solutions of the Korteweg–de Vries (KdV) equation. The first method is used to solve the Cauchy initial-value problem on the line for rapidly decaying initial data. The second method is used to compute finite-genus solutions of the KdV equation. The combination of these numerical methods allows for the computation of exact solutions that are asymptotically (quasi-)periodic finite-gap solutions and are a nonlinear superposition of dispersive, soliton and (quasi-)periodic solutions in the finite (x, t)-plane. Such solutions are referred to as superposition solutions. We compute these solutions accurately for all values of x and t. (paper)

  14. The generalized tanh method to obtain exact solutions of nonlinear partial differential equation

    OpenAIRE

    Gómez, César

    2007-01-01

    In this paper, we present the generalized tanh method to obtain exact solutions of nonlinear partial differential equations, and we obtain solitons and exact solutions of some important equations of the mathematical physics.

  15. Traveling Wave Solutions of ZK-BBM Equation Sine-Cosine Method

    Directory of Open Access Journals (Sweden)

    Sadaf Bibi

    2014-03-01

    Full Text Available Travelling wave solutions are obtained by using a relatively new technique which is called sine-cosine method for ZK-BBM equations. Solution procedure and obtained results re-confirm the efficiency of the proposed scheme.

  16. Two reactions method for accurate analysis by irradiation with charged particles

    International Nuclear Information System (INIS)

    Ishii, K.; Sastri, C.S.; Valladon, M.; Borderie, B.; Debrun, J.L.

    1978-01-01

    In the average stopping power method the formula error itself was negligible but systematic errors could be introduced by the stopping power data used in this formula. A method directly derived from the average stopping power method, but based on the use of two nuclear reactions, is described here. This method has a negligible formula error and does not require the use of any stopping power or range data: accurate and 'self-consistent' analysis by irradiation with charged particles is then possible. (Auth.)

  17. Synthesis of Gold Nanoparticles Stabilized in Dextran Solution by Gamma Co-60 Ray Irradiation and Preparation of Gold Nanoparticles/Dextran Powder

    Directory of Open Access Journals (Sweden)

    Phan Ha Nu Diem

    2017-01-01

    Full Text Available Gold nanoparticles (AuNPs in spherical shape with diameter of 6–35 nm stabilized by dextran were synthesized by γ-irradiation method. The AuNPs were characterized by UV-Vis spectroscopy and transmission electron microscopy. The influence of pH, Au3+ concentration, and dextran concentration on the size of AuNPs was investigated. Results indicated that the smallest AuNPs size (6 nm and the largest AuNPs size (35 nm were obtained for pH of 1 mM Au3+/1% dextran solution of 5.5 and 7.5, respectively. The smaller Au3+ concentration favored smaller size and conversely the smaller dextran concentration favored bigger size of AuNPs. AuNPs powders were prepared by spay drying, coagulation, and centrifugation and their sizes were also evaluated. The purity of prepared AuNPs powders was also examined by energy dispersive X-ray (EDX analysis. Thus, the as-prepared AuNPs stabilized by biocompatible dextran in solution and/or in powder form can be potentially applied in biomedicine and pharmaceutics.

  18. Enhanced exact solution methods for the Team Orienteering Problem

    NARCIS (Netherlands)

    Keshtkaran, M.; Ziarati, K.; Bettinelli, A.; Vigo, D.

    2016-01-01

    The Team Orienteering Problem (TOP) is one of the most investigated problems in the family of vehicle routing problems with profits. In this paper, we propose a Branch-and-Price approach to find proven optimal solutions to TOP. The pricing sub-problem is solved by a bounded bidirectional dynamic

  19. WYD method for an eigen solution of coupled problems

    Directory of Open Access Journals (Sweden)

    A Harapin

    2016-04-01

    Full Text Available Designing efficient and stable algorithm for finding the eigenvalues andeigenvectors is very important from the static as well as the dynamic aspectin coupled problems. Modal analysis requires first few significant eigenvectorsand eigenvalues while direct integration requires the highest value toascertain the length of the time step that satisfies the stability condition.The paper first presents the modification of the well known WYDmethod for a solution of single field problems: an efficient and numericallystable algorithm for computing eigenvalues and the correspondingeigenvectors. The modification is based on the special choice of thestarting vector. The starting vector is the static solution of displacements forthe applied load, defined as the product of the mass matrix and the unitdisplacement vector. The starting vector is very close to the theoreticalsolution, which is important in cases of small subspaces.Additionally, the paper briefly presents the adopted formulation for solvingthe fluid-structure coupled systems problems which is based on a separatesolution for each field. Individual fields (fluid and structure are solvedindependently, taking in consideration the interaction information transferbetween them at every stage of the iterative solution process. The assessmentof eigenvalues and eigenvectors for multiple fields is also presented. This eigenproblem is more complicated than the one for the ordinary structural analysis,as the formulation produces non-symmetrical matrices.Finally, a numerical example for the eigen solution coupled fluidstructureproblem is presented to show the efficiency and the accuracy ofthe developed algorithm.

  20. Computer Facilitated Mathematical Methods in Chemical Engineering--Similarity Solution

    Science.gov (United States)

    Subramanian, Venkat R.

    2006-01-01

    High-performance computers coupled with highly efficient numerical schemes and user-friendly software packages have helped instructors to teach numerical solutions and analysis of various nonlinear models more efficiently in the classroom. One of the main objectives of a model is to provide insight about the system of interest. Analytical…