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Sample records for irradiated pollen electronic

  1. The change of pollen traits in gladiolus irradiated by electron beam

    International Nuclear Information System (INIS)

    Zhang Zhiwei; Wang Dan; Zhang Dongxue; Yuan Xianghui

    2007-01-01

    In order to investigate the feasibility of electron beam induced mutation on Gladiolus and the effects of electron beam with different doses on pollen traits, M1 generation pollen traits were studied by use of 3MeV electron beams with seven doses of 0Gy, 40Gy, 80Gy, 120Gy, 160Gy, 200Gy, 240Gy. It has been shown that the sterile pollen rate of M1 generation is higher than that of control. At low dose there had no obvious effects on the viability and germination rate of M1 generation pollen. With the increase of irradiation dose, the viability and germination rate of pollen was decreased and the difference had statistical significance (P<0.05). Comparing (SEM) photograph of the pollen shapes of M1 generation with control, within a certain doses level, mutagenic effects on pollen increased with the dose increasing in the angle of polynology. Variations of mutagenic effect extent were found at the different irradiation dosage. The EST isozymes expression of M1 generation pollen was obviously changed by electron beam irradiation confirmed by use of PAGE electrophoresis. EST patterns of pollen of Gladiolus irradiated at the dose no more than 120Gy were similar to CK, but there were some differences in the vigor of isozymes. The EST bands added or absent had been observed at the dose more than 160Gy compared to CK. There were a special EST band more and 2 EST bands less in plants treated by both 160Gy and 200Gy electron beam irradiation, and a special EST band more and 1 EST bands less in plants treated by 240Gy electron beam irradiation. The vigor of isozymes of plants treated at the dose more than 160Gy showed some respective differences compared to the other treated and CK's. These results revealed that electron beam irradiation is an effective way for Gladiolus breeding. (authors)

  2. Effect of electron beam irradiation on pollen mother cells of gladiolus 'chaoji'

    International Nuclear Information System (INIS)

    Zhang Zhiwei; Wang Dan; Wen Fangping Zhang Xiaoxue

    2008-01-01

    In order to test the effects of various doses of electron beam on M1 generation pollen mother cells (PMC), the corm of gladiolus 'chaoji' was irradiated by electron beam with 3 MeV energy. Some abnormalities of meiosis of pollen mother cells were studied and the bands of protein subunit were analyzed by SDS-PAGE for the irradiated corm. The genetic damage at meiosis of gladiolus is observed, and the types of chromosomal aberrations are laggard chromosomes, chromosomal bridge, chromosome outside nucleus, unequal separation of chromosome, micronuclei and so on. Some trispores and paraspores are viewed at tetraspore period. The shape and size of the microspores vary in some treated materials, and most of microspores display little volume. The statistic of aberrance types and frequencies in PMCs show that aberrance types are chromosome outside nucleus and micronuclei mostly. The SDS-PAGE result shows that protein expression of M1 generation pollen is obviously changed by electron beam irradiation. Low dose of electron beam has obvious effects, and some special proteins subunit bands are found among varieties of irradiation dosage respectively. The protein bands are absent at the dose more than 160 Gy compared to low dose of electron beam. The results indicate that electron beam irradiation is an effective way for gladiolus breeding. (authors)

  3. Pollen irradiation and possible gene transfer in Nicotiana species

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1985-01-01

    , and Petunia parodii with irradiated pollen from N. alata and Petunia hybrida showed no evidence of gene transfer, nor did experiments with irradiated mentor pollen. This indicates that gene transfer with irradiated pollen between non-crossing species or between species giving sterile hybrids is probably...

  4. Influence of gamma irradiation on pollen viability, germination ability ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-12-15

    Dec 15, 2009 ... minor cross-incompatibilities and physiological studies of incompatibility ... campanula shape of the flowers attractive for insect. (bees are ..... irradiation of cacao (Theobroma cacao L.) pollen: Effect on pollen grain viability ...

  5. Pollen-gamma irradiation on pineapple and pollination using irradiated pollen

    International Nuclear Information System (INIS)

    Benega, R.; Cisneros, A.; Martinez, J.; Arias, E.; Yabor, L.; Isidron, M.; Castillo, E.; Fernandez, J.

    1997-01-01

    In order to try to induce haploid plants, pineapple (Ananas comosus (L.) ;err.) pollen grains were gamma-rays irradiated with a Co 60 source at rates of doses from 0 to 300 Gy. The effect of gamma-rays on the generative-nucleus division and vitro pollen viability as well as, seed contents and plantlets obtained after pollinations was analysed. The were reducing in the division frequencies of generative nucleus at all assayed doses. The LD50 was achieved among 200 and 250 Gy. There were not differences on pollen viability in the rates of assayed doses. Seed contents were dose-dependent. The percentages of seed full and seed containing only embryos decreases at increasing of irradiation doses. Contrary effect was observed on the seed empty. Some plantlets regenerated from the different irradiation doses showed phenotypes with small and leaves and short inter nodes

  6. Two-peaked dose curves for irradiated pollen growth

    International Nuclear Information System (INIS)

    Andrejchenko, S.V.; Grodzinskij, D.M.

    1992-01-01

    The effect of γ-radiation on growth activity of bicellular pollen of hybrid petunia has been investigated. Irradiation of pollen with doses of 5 to 70 Gy increases the pollen tube growth in an artificial culture medium. As the radiation dose increases the germination ability of pollen gradually decreases and the mean pollen tube length shortens, which is accompanied by the suppression of the generative cell division into spermia and inhibition of the unscheduled incorporation of labelled thymidine into DNA. With radiation doses of 1200 to 1700 Gy some pollen tubes grow intensively. It is suggested that the phenomenon observed lays the basis for the gametic transformation

  7. The effect of irradiation on date palm pollen grains

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, M M; Alajaily, F R [The National Academy for Scientific Research Tripoli (Libyan Arab Jamahiriya)

    1995-10-01

    The evaluation of male date palm is very important in date palm culture, it is very well known that the source of pollen has its influence on fruit set, physical and chemical characters of the fruits. Date pollen was collected from previously studied male date palm trees. The pollen was subjected to the following irradiation treatments: 0,5, 10, 20, 40, 80 krad. The irradiated pollen was treated with acetocarmine and its viability was studied under the light microscope. No differences were observed between the treated pollen and the control. The pollen was germinated on agar, sucrose and boric acid media in an incubator at 27 degree C for hours. Germination count under the light microscope indicated that there were no significant differences between 5, 10, 20 krad treatments and the control, but the high doses reduced the germination percentage. The irradiated pollen used to pollinate date palm trees and the effect of metaxynia was studied. 3 tabs.

  8. Transference of genetic information through irradiated pollen

    Energy Technology Data Exchange (ETDEWEB)

    Dryanovska, O A [Bylgarska Akademiya na Naukite, Sofia. Inst. po Genetika

    1983-01-01

    Blossoms are used as mothers of two longistylous with male sterility varieties of Deva and Hera without anthocyan on the stem from L. esculentum (Mill.) (L.), which were pollinated with irradiated dallenform L. peruvianum (L.) with anthocyan on the stem, with 10 AND 200 Kr of gamma-rays, 5 and 10 min from a source of mixed (long and short) UV-rays, at a distance of 20 cm, while the control blossoms were pollinated with a mixture of other cultivated plants. Irradiation with gamma rays was carried out on a gamma device with a dose power of up to 1,500 R/m. The results show that irradiated pollen tube with the male chromatin induces gynogenesis and seconadary diploidization. It is assumed that some of the microfragments irradiated with high doses of radiation contain a functionally active gene or the genes responsible for anthocyan synthesis. These microfragments are capable of combining with the nonirradiated mother chromatin and they become involved and operate in the process of development of the mother sex cells and at the early embryogenesis, as a result of which anthocyan appears in the developing plants.

  9. Transference of genetic information through irradiated pollen

    International Nuclear Information System (INIS)

    Dryanovska, O.A.

    1983-01-01

    Blossoms are used as mothers of two longistylous with male sterility varieties of Deva and Hera without anthocyan on the stem from L. esculentum (Mill.) (L.), which were pollinated with irradiated dallenform L. peruvianum (L.) with anthocyan on the stem, with 10 AND 200 Kr of gamma-rays, 5 and 10 min from a source of mixed (long and short) UV-rays, at a distance of 20 cm, while the control blossoms were pollinated with a mixture of other cultivated plants. Irradiation with gamma rays was carried out on a gamma device with a dose power of up to 1,500 R/m. The results show that irradiated pollen tube with the male chromatin induces gynogenesis and seconadary diploidization. It is assumed that some of the microfragments irradiated with high doses of radiation contain a functionally active gene or the genes responsible for anthocyan synthesis. These microfragments are capable of combining with the nonirradiated mother chromatin and they become involved and operate in the process of development of the mother sex cells and at the early embryogenesis, as a result of which anthocyan appears in the developing plants

  10. Storage and irradiation of Cucumis pollen and their influence on pollen vitality

    International Nuclear Information System (INIS)

    Oost, E.H.; Nijs, A.P.M. den

    1979-01-01

    In connection with an interspecific hybridization programme and a mentor pollen experiment in Cucumis, the optimal storage conditions and in vitro germination medium for both fresh and irradiated pollen of the cultivated cucumber and two wild African Cucumis species have been searched for. (Auth.)

  11. The dose effect of irradiated rice pollen on double fertilization

    International Nuclear Information System (INIS)

    Wang Houcong; Chen Zhengming; Chen Ruming; Qiu Simi; Yang Juemin; Yang Huijie

    1995-01-01

    The mature panicles of rice were treated with 60 Co γ-rays in the range of 0∼0.372 kGy. The male sterile line used as the female plants were fertilized with γ-irradiated pollen manually. The dose effect of the irradiated pollen on double fertilization was investigated. It was found that double fertilization of the irradiated pollen was suppressed to different degrees as compared with the control. The effect was noticeable as that the fusion time of the male nucleolus with the female one was delayed with the increasing of γ-radiation dose. The delayed time was less than 13 hours when the dose was below 0.186 kGy and it was more than 15 hours when the dose was above 0.279 kGy. Furthermore, several types of deformed embryonic cells and endosperm nuclei were observed

  12. 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

  13. 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

  14. Evidence for DNA repair after ultraviolet irradiation of Petunia hybrida pollen

    International Nuclear Information System (INIS)

    Jackson, J.F.; Linskens, H.F.; Katholieke Universiteit Nijmegen; Katholike Universiteit Nijmegen

    1978-01-01

    Ultraviolet irradiation of Petunia hybrida pollen led to an unscheduled labelling of pollen DNA by 3 H-thymidine during the early stages of germination. Hydroxyurea increased this DNA labelling, while added boron, required absolutely for pollen germination, tube elongation and tube generative cell mitosis, was not needed for this repair-like DNA synthesis. (orig.) [de

  15. Pollination with gamma-irradiated pollen and seed development in kiwifruit (Actinidia deliciosa var. deliciosa)

    International Nuclear Information System (INIS)

    Musial, K.

    1997-01-01

    Full text. The effects of pollen irradiation at 70 and 90 kr on seed set were studied in Actinidia deliciosa var. deliciosa. Pollination with irradiated pollen affected seed development and contents. Rising irradiation doses increased the percentages of empty seeds and decreased the percentages of seeds containing embryos with endosperm. Moreover, pollination with heavily irradiated pollen led to the formation of seeds containing the endosperm only. Embryo and endosperm size was also strongly influenced by irradiated pollen. The length of endosperms was reduced at all levels of pollen irradiation compared to the non-irradiated controls; the embryo development was conspicuously retarded. Cells in endosperm resulting from the treatments differed in the presence and number of starch grains. (author)

  16. Electron beam irradiating device

    Energy Technology Data Exchange (ETDEWEB)

    Shinohara, K

    1969-12-20

    The efficiency of an electron beam irradiating device is heightened by improving the irradiation atmosphere and the method of cooling the irradiation window. An irradiation chamber one side of which incorporates the irradiation windows provided at the lower end of the scanner is surrounded by a suitable cooling system such as a coolant piping network so as to cool the interior of the chamber which is provided with circulating means at each corner to circulate and thus cool an inert gas charged therewithin. The inert gas, chosen from a group of such gases which will not deleteriously react with the irradiating equipment, forms a flowing stream across the irradiation window to effect its cooling and does not contaminate the vacuum exhaust system or oxidize the filament when penetrating the equipment through any holes which the foil at the irradiation window may incur during the irradiating procedure.

  17. The influence of pollen γ-irradiation of the growth and development of plants

    International Nuclear Information System (INIS)

    Andrejchenko, S.V.; Grodzinskij, D.M.

    1986-01-01

    A study was made on the influence of pollen gamma irradiation on induction of phenotypic mutation in F 1 hybrid petunia. Some dose regularities characterizing the rate of growth and development of daughter plants were revealed. It was shown that seed formation and embryogenesis depend directly on the degree of pollen gamma irradiation damage

  18. Pollen

    Science.gov (United States)

    ... that pollen can also be transported indoors on people and pets. Dry your clothes in an automatic dryer rather ... that pollen can also be transported indoors on people and pets. Dry your clothes in an automatic dryer rather ...

  19. Induced parthenocarpy with pollen irradiated with gamma rays

    International Nuclear Information System (INIS)

    Dryanovska, O.

    1975-01-01

    The results of serial experiments carried out during 1971-1974 using different vegetable crops for the purpose of obtaining parthenocarpous fruits with pollen irradiated with gamma rays are summed. Different varieties of tomatoes, cucumbers and sugar melons are used. The pollen was irradiated on the day on which it was collected with 1 to 500 kR (1500-1000 R/min) with immediate pollination of the respective flowers. The pollination of the flower was conducted with or without castration and with or without isolation depending on the varieties and the conditions of cultivating the plants. The fruits thus obtained were normal in size and shape and contained degenerated seed (flakes) witout cavities. Degustations in all cases established a fuller and richer taste in comparison with the control fruits. Biochemical indices for the same tomatoes varieties (sugars, vitamin C, acidity, dry substance determined refractometrically) show that the quality of the experimental fruits is better than the control ones. (A.B.)

  20. Post-X-irradiation effects on petunia pollen germinating in vitro and in vivo

    International Nuclear Information System (INIS)

    Gilissen, L.J.W.

    1978-01-01

    The germination of Petunia hybrida L. pollen grains in germination medium, containing 10% sucrose and 0.01 % H 3 BO 3 , was linearly related to relative humidity (RH): being minimal at 0 % RH and maximal at 100 % RH. The low germination at 0 % RH was completely restored after transfer to 100 % RH. Germination in medium decreased with increasing X-ray exposures between O and 400 kR. This decrease was caused by pollen rupture. No in vitro germination occurred at exposures of 400 kR and more. The radiosensitivity of pollen in vitro was minimal at 80 % RH. Transfer of pollen to the stigma post-X-irradiation resulted in resistance to much higher exposures of irradiation (<750 kR). The differences in radiosensitivity of the pollen germinated in vitro and in vivo are due possibly to the differences in composition of the germination medium and the stigmatic exudate. Pollen tube growth of irradiated pollen after compatible or incompatible pollination at first showed retarded then normal tube growth. A conclusion is that X-irradiation of pollen cannot influence the characteristics of pollen tube growth after compatible or incompatible pollination. (author)

  1. Effects of gamma-irradiation on the main nutritional composition of rape pollen

    International Nuclear Information System (INIS)

    Lu Yuan; Wang Darui; Han Denbao; Liu Deshen

    1990-01-01

    Storaged pollen is easy to be destroyed by bacterium, moulds and insects. In order to solve this problem we tried to irradiate pollen with doses of 1.5 kGy and 2.5 kGy of γ-rays and then analyse its main nutritional compositions so to find out the effects of gamma-irradiation on amino acids, protein, carbohydrate, fat, vitamines etc. The results have been showed that the above doses gamma-irradiation doesn't notably influence the main nutritional compositions of rape pollen, even if they are storaged for three or six months at 4 deg C

  2. Effect of gamma irradiation on pollen and seed fertility in pigeon pea

    International Nuclear Information System (INIS)

    Ahmed John, S.

    1997-01-01

    A study was undertaken in pigeon pea parents and their F 1 hybrid to analyse the pollen and seed fertility following gamma irradiation. It is found that the reduction of pollen and seed fertility in pigeon pea was lesser over those of black gram and cowpea. 5 refs., 1 tab

  3. Pollen

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past vegetation and climate derived from pollen found in lake and ocean sediments. Parameter keywords describe what was measured in this data set....

  4. Influence of penetration controlled irradiation with charged particles on tobacco pollen

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Dept. of Radiation Research for Environment and Resources; Tanaka, Atsushi; Tano, Shigemitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Advanced Science Research Center; Inoue, Masayoshi [Kyoto Prefectural Univ. (Japan). Faculty of Agriculture

    1997-09-01

    To investigate the effect of local irradiation on biological systems, an apparatus for penetration controlled irradiation with charged particles was set up. By comparison of ranges of 1.5 MeV/u He{sup 2+} between the theoretically calculated ranges and the practical ranges using RCD dosimeter, it was demonstrated that the range of particles could be controlled linearly by changing the distance from the beam window in the atmosphere to a target. In addition, the penetration controlled irradiation of tobacco pollen increased the frequency of `leaky pollen`. The increased frequency of the leaky pollen suggests that a damage in the pollen envelope would be induced at the range-end. (orig.)

  5. Electron irradiation of zeolites

    International Nuclear Information System (INIS)

    Wang, S.X.; Wang, L.M.; Ewing, R.C.

    1999-01-01

    Three different zeolites (analcime, natrolite, and zeolite-Y) were irradiated with 200 keV and 400 keV electrons. All zeolites amorphized under a relatively low electron fluence. The transformation from the crystalline-to-amorphous state was continuous and homogeneous. The electron fluences for amorphization of the three zeolites at room temperature were: 7.0 x 10 19 e - /cm 2 (analcime), 1.8 x 10 20 e - /cm 2 (natrolite), and 3.4 x 10 20 e - /cm 2 (zeolite-Y). The different susceptibilities to amorphization are attributed to the different channel sizes in the structures which are the pathways for the release of water molecules and Na + . Natrolite formed bubbles under electron irradiation, even before complete amorphization. Analcime formed bubbles after amorphization. Zeolite-Y did not form bubbles under irradiation. The differences in bubble formation are attributed to the different channel sizes of the three zeolites. The amorphization dose was also measured at different temperatures. An inverse temperature dependence of amorphization dose was observed for all three zeolites: electron dose for amorphization decreased with increasing temperature. This unique temperature effect is attributed to the fact that zeolites are thermally unstable. A semi-empirical model was derived to describe the temperature effect of amorphization in these zeolites

  6. Effects of Gamma Irradiation on Quality Characteristic and Microbiological Safety of Rape (Brassica napus) Pollen

    International Nuclear Information System (INIS)

    Kim, Kyoung-Hee; Jeong, Su-Ji; Kim, Dam; Yook, Hong-Sun; Kim, Kwang-Hun

    2013-01-01

    This study is carried out to sanitize rape (Brassica napus) pollen by gamma irradiation. Rape pollens were treated with 0, 5, 10 and 15 kGy gamma irradiations, and then analyzed for the following: general composition, microbial population, reducing sugar, Hunter color values, TBARS (2-thiobarbituric acid reactive substances) values, and VBN (volatile basic nitrogen). Mold and coliform bacteria were not detected in the samples irradiated at 5 kGy or more. Yeasts and total aerobic bacteria were not detected in the samples irradiated at 10 kGy or more (102 CFU/g). Moisture, ash, crude protein, crude fat, carbohydrate, reducing sugar and the contents of volatile basic nitrogen in the irradiated pollen did not show any significant changes by irradiation. Hunter color values, L, a and b values were decreased with increment of irradiation dose. TBARS values were increased with an increment of irradiation dose. In conclusion, gamma irradiation at 5 kGy was considered to be an effective treatment to control for mycotoxin producing fungi in rape pollen to minimize changes of general composition and physicochemical properties. Further studies should be investigated to reduce the detrimental effects induced by irradiation

  7. Studies on mutagenic activity of 60Co γ-ray irradiated rape pollen

    International Nuclear Information System (INIS)

    He Weishun; Liu Aihua; Lin Shiying; Xiong Xikun

    1989-01-01

    In the present study on disinfection, the rape pollen was irradiated with 2.5 kGy 60 Co γ-ray. Micronuclei, sister chromatid exchanges (SCE) of bone marrow cells and chromosomal aberrations of meiotic cells in mice were used as an indicater of chromosomal damage to study the mutagenicity of irradiated rape pollen. The results are as follows: (1) The frequency of micronuclei in polychromatic erythrocytes is 2.00 per mille; nucleated cells is 0.8 per mille in control group. In the numbers of polychromatic erythrocytes and nucleated cells with micronuclei, there is no obviously difference in irradiated and unirradiated groups. (2) SCE incidence of control group is 2.01 ± 0.12/cell. No significant difference in the frequency of SCE exists between non-irradiated rape pollen and the control groups. But the frequency of SCE in irradiated rape pollen group (3000 mg/kg/day x 7) is 2.36 ± 0.12/cell; high dose group (6000 mg/kg/day x 7) is 2.96 ± 0.14/cell. In comparison with control group, there is a significant difference. (3) The chromatid breaks, fragments, and univalents in primary spermatocytes have been obseved. The frequencies of chromosomal aberration showed no obviously difference among irradiated and non-irradiated rape pollen groups

  8. Sewage sludge irradiation with electrons

    International Nuclear Information System (INIS)

    Tauber, M.

    1976-01-01

    The disinfection of sewage sludge by irradiation has been discussed very intensively in the last few months. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. AEG-Telefunken is building an irradiation plant with a 1.5 MeV, 25 mA electron accelerator, to study the main features of electron irradiation of sewage sludge. (author)

  9. Gamma Irradiation Effects on Oil Palm (Elaies Guineensis) Pollen Viability, Fruits and Bunch Formations

    International Nuclear Information System (INIS)

    Aida Nazlyn Nazari; Azhar Mohamad; Shuhaimi Shamsuddin

    2014-01-01

    Assessing performance and genetic diversity of the wild material of oil palm is important for understanding genetic structure of natural oil palm populations towards improvement of the crops. This information is important for oil palm breeding programs, and also for continued ex-situ conservation of the germplasm and breeding program in Malaysia. Mutation induction is one of the alternative ways in creating variants for selection in the breeding program. In this study, evaluation on the effect of irradiated pollen towards pollen viability, bunches formation and no. of parthenocarpic fruits were conducted. Series of acute gamma radiation at dose 0, 10, 20, 40, 50, 100, 200, 300, 500, 100 and 2000 Gy were exposed to Elaies guineensis pollen. Increasing level of irradiation higher than 200 Grays (Gy) affects pollen viability based on the 12 consecutive days observation evaluated in situ conditions. Besides, at this level of irradiation (> 200 Gy), the pollen tube formation were disrupted and subsequently unable the pollen to reach the ovule which cause the embryo to aborted and contributed to the formation of parthenocarpic fruits and rotten bunches. These observations suggested that at low levels of irradiation (< 200 Gy) may damage only part of the generative nucleus while maintaining its capacity to fertilise the egg cells and lead to hybridization. (author)

  10. Use of γ-irradiated pollen for the gene transfer in Petunia

    International Nuclear Information System (INIS)

    Andrejchenko, S.V.; Grodzinskij, D.M.

    1986-01-01

    Possibility of using gamma-irradiated pollen for the gene transfer in Petunia is shown. Occurrence of gametic transformation provided not only the gene integration and expression but also their transfer to the daughter generations. The described methodical approach to construction of the plant eucariotic cell genome is based not only on its simplicity but also on the fact that gamma-radiation doses of 1000 Gy and higher have no desorganizing effect on the chromatine structure in such a degree that its transcription activity is completely lost. Besides, selective inactivation of the locus radiation in the pollen genome is much assisted by their different radioresistance. Though the gene transfer by gametic transformation is mostly irregular but its probability may be increased by the correct selection of the pollen irradiation dose in a range in which the growth of pollen tube before ovary is conserved and reparation of one-strand and two-strand DNA breaks preventing chromatine fragmentation is suppressed

  11. Overcoming interspecific incompatibility in the cross Brassica campestris ssp. japonica x Brassica oleracea var. botrytis using irradiated mentor pollen page

    International Nuclear Information System (INIS)

    Sarla, N.

    1988-01-01

    The cross B. campestris ssp. japonica x B. oleracea var. botrytis fails due to incompatibility barrier at the stigma. To realize this cross, irradiated compatible pollen (mentor pollen) was used before the incompatible pollination. The presence of mentor pollen stimulated the incompatible pollen to germinate and effect fertilization and seed set. One hybrid was thus obtained. Most of the seeds were inviable. Of the 5 plants raised one was a hybrid and 4 resembled the female parent. 1 tab., 7 refs

  12. Effects of gamma irradiation of pollen on parthenogenetic haploid production in muskmelon (Cucumis melo L.)

    International Nuclear Information System (INIS)

    Cuny, F.; Grotte, M.; Dumas de Vaulx, R.; Rieu, A.

    1993-01-01

    The effects of increasing gamma ray exposures on muskmelon pollen of the Védrantais genotype were evaluated after autofertilization and hybridization with the F1.G1 genotype. Regardless of doses of between 0.15 and 1.6 kGy, fruit set and number of seeds per fruit were comparable to those of the control. The pollen tube from pollen irradiated with up to 2.5 kGy grew in styles and reached the ovules. When pollen was cultivated in vitro, relatively high doses of irradiation (1.6 kGy) were needed to reduce the level of germination. Radiation-induced changes in the generative nucleus led to the formation of two chromosomally unbalanced sperm cells (as indicated by the appearance of morphological dimorphism) which induced parthenogenetic development of the egg to form a haploid embryo. Haploid embryo production by gamma-irradiated pollen was genotype dependent. For exposures of between 0.15 and 2.5 kGy, the production of embryos was the same, about 3.4%; a maximum of 70% of these embryos placed in a specific culture medium produced haploid plants. The ploidy of the plantlets in vitro was determined by flow cytometry. No aneuploidy was detected. All resulting plants exhibited normal phenotypes. (author) [fr

  13. Cytological effects of pollen irradiation on wheat x leymus angustus hybrids

    International Nuclear Information System (INIS)

    Li Guiying; Wang Linqing; Shi Jinguo

    2000-01-01

    Cytological effects of pollen irradiation on wheat x Leymus angustus hybrids were studied using callus clones and their derived plants of hybrid embryos as experimental materials. The results showed that variation range of chromosome number (VRCN) of hybrid callus clone became wider after pollination with irradiated paternal pollen. VRCN of the control clone was 43-64, and 26-66 was found in 9 Gy treatment clone. The average chromosome number per cell decreased by 4.9. Pollen irradiation enhanced chromosomal structural aberration (CSA). The CSA frequency was 45.35% in the control clone, and 77.31% in 9 Gy treatment clone. The main CSA in the control clone was telo-centric chromosome. Except for telo-centric chromosomes, there were also minichromosomes in 9 Gy treatment clone with the similar frequency to telo-centric chromosomes. The higher frequency of dicentric and ring chromosomes and fragments in 9 Gy treatment showed that pollen irradiation enhanced chromosomal translocation and recombination

  14. Ultraviolet irradiation of maize (Zea Mays L.) pollen grains. Pt. 2

    International Nuclear Information System (INIS)

    Pfahler, P.L.; Linskens, H.F.

    1977-01-01

    Mature pollen grains from two single cross (F 1 ) hybrids, Wf9 x H55 and K64 x K55, were exposed to eleven levels (0 to 6.80 erg/cm 2 x 10 5 at 0.68 intervals) of ultraviolet irradiation and then were used to pollinate their source. Height and kernel characteristics (kernel weight, weight/100 kernels, kernel number) of individual F 2 plants produced by the normal F 2 kernels obtained from these pollinations were measured within each level and population. Highly significant exposure x population interactions were found for all characters, indicating that the effect of irradiation depended on the genetic source of the pollen grains. Increasing exposure increased or did not change the mean of Wf9 x H55 and decreased the mean in K64 x K55 for all characters. For coefficient of variation values, the interaction, exposure x population, was not significant for any character measured, indicating that irradiation-induced variability was unrelated to pollen source. The results indicate that pollen source strongly influenced the effect of ultraviolet irradiation on plant means but had no influence on variability. (orig.) [de

  15. Electron irradiation of power transistors

    International Nuclear Information System (INIS)

    Hower, P.L.; Fiedor, R.J.

    1982-01-01

    A method for reducing storage time and gain parameters in a semiconductor transistor includes the step of subjecting the transistor to electron irradiation of a dosage determined from measurements of the parameters of a test batch of transistors. Reduction of carrier lifetime by proton bombardment and gold doping is mentioned as an alternative to electron irradiation. (author)

  16. Surmounting self-incompatibility in pineapple (Ananas comosus L.) with pollen irradiation

    International Nuclear Information System (INIS)

    Subramanian, N.; Iyer, C.P.A.; Singh, Rajendra

    1981-01-01

    Irradiation was investigated as a tool to overcome self-incompatibility in pineapple. Pollen grains were irradiated with 15, 20, 25 kr gamma radiation from cobalt-60 and were used for pollination on the stigma of the same inflorescence. Observations on seed-set were made when the fruits were ripe. It was observed that 20 kr gamma radiation was effective in overcoming self-incompatibility. (M.G.B.)

  17. The effect of UV irradiated vegetative and generative nuclei as well as cytoplasm on pollen tube growth of Pinus Silvestris

    International Nuclear Information System (INIS)

    Zelles, L.; Seibold, H.W.; Ernst, D.E.W.; Technische Univ. Hannover

    1976-01-01

    Pollen grains of Pinus Silvestris were irradiated with UV-rays, and the stimulation, or restraint of gemination was studied. Gemination of the pollen was retarded by irradiation of the nucleus. This book place proportionally to the increasing doses: The conditions of irradiation and the effects of the stimulation and retardation are described in detail. Different dose rates with different effects on nucleus and cytoplasma are observed. (AJ) [de

  18. Cucumber (Cucumis sativus L.) embryo development in situ after pollination with irradiated pollen

    International Nuclear Information System (INIS)

    Faris, N.M.; Niemirowicz-Szczytt, K.

    1999-01-01

    Embryological studies were undertaken to compare the normal development of cucumber endosperm and embryo with that observed after pollination with gamma-irradiated pollen (0.1 and 0.3 kGy). Delayed penetration of the pollen tube occurred at both irradiation doses. Endosperm and embryo development was also delayed, but was initiated within 6 days after pollination in 100% of embryo sacs at 0.1 kGy and in 70-80% at 0.3 kGy. Various abnormalities in endosperm and embryo cell structure confirmed progressive degeneration, which occurred earlier with the higher dose of irradiation. Degeneration increased dramatically; only 30-40% of the embryos reached the globular stage 15 days after pollination. (author)

  19. Some problems of using irradiated pollen in genetics and selection of winter soft wheat (Triticum acstivum)

    International Nuclear Information System (INIS)

    Bovkis, E.N.

    1978-01-01

    For the first time the mutagenous efficiency of gamma-irradiation of male gametes(pollen) for genetic and selection purposes has been studied using three sorts of winter wheat. It is shown, that a critical irradiation dose for soft wheat in respect of degree of reducing the mass of 1000 grains and survive is 2.0 krad. Application of irradiated pollen results in a wide spectrum of mutagenous changeability, at that, one part of forms remains constant and the other is splitted according to the type of intraspecific hybrids. Pollen irradiation doses are grounded to produce mutants having some important selection features. Irradiation doses from 0.25 to 0.5 krad are most effective to produce mutants with productive ears and from 1.0 to 1.5 krad to produce short-stem ones. More than 80 mutants are studied in respect of productivity and other indications in a control nursery. Combination productivity value of some short-stem mutants has been studied; it is shown, that as a rule it is preserved at the level of initial sorts. The use of historical method for understanding the regularities of mutant appearance is of great theoretical interest during the investigations. It has been established, that mutants relating to different varieties appear with unequal frequency, which, possibly, is due to the species genotype

  20. Pollen and spores as biological recorders of past ultraviolet irradiance

    NARCIS (Netherlands)

    Jardine, P.E.; Fraser, W.T.; Lomax, B.H.; Sephton, M.A.; Shanahan, T.M.; Miller, C.S.; Gosling, W.D.

    2016-01-01

    Solar ultraviolet (UV) irradiance is a key driver of climatic and biotic change. Ultraviolet irradiance modulates stratospheric warming and ozone production, and influences the biosphere from ecosystem-level processes through to the largest scale patterns of diversification and extinction. Yet our

  1. Effect of pollen irradiation on hybridization of wheat and Eltrigia intermedia and their embryo development

    International Nuclear Information System (INIS)

    Li Guiying; Wang Linqing; Shi Jinguo

    2005-01-01

    Spikes of Eltrigia intermedia were radiated with 5-100 Gy γ-ray during anthesis, and then their pollens were collected to pollinate to the common wheat 'J-11' and 'Chinese Spring'. The effects of pollen irradiation on the seed setting, embryo development, embryo culture and plantlet rate were studied. The results showed that low dose (5-9 Gy) of irradiation enhanced the seed setting for Chinese spring x E. intermedia, but no such effect for J-11xE. intermedia. Irradiation with all doses damaged embryo development, percentage of seeds with embryos; rate of immature hybrid embryos developing into plantlets decreases with the increased doses. Percentage of seeds with abnormal embryos increased significantly with the doses. 12.9%-14.5% of embryos could develop into plants in 30 Gy treatment, which seldom occur to wheat. Embryos in 50 Gy-100 Gy treatment were affected so serious that even none of them could develop into plants in vitro culture. It may be an effective approach to obtaining more mutants and enhancing induced mutation breeding by using combination of pollen irradiation, immature embryo rescue and anther culture of the resultant progenies. (authors)

  2. The ultrastructure of pollen grain surface in allotetraploid petunia (Petunia hybrida hort. superbissima as revealed by scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    S. Muszyński

    2015-01-01

    Full Text Available The ultrastructure of pollen grain surface in allotetraploid petunias was analyzed by scanning electron microscopy. The pollen grain wall is developed into characteristic pattern of convulations.

  3. UV dosimetry in pollen of Pinus silvestris and stimulation studies of pollen tube growth after irradiation with UV and ionizing radiations

    International Nuclear Information System (INIS)

    Seibold, H.W.

    1976-01-01

    Pollen tube growth after exposure to UV- and ionizing radiation was investigated in Pinus silvestris as a function of different parameters. The preconditions for this are an exact UV dosimetry and the conversion of the UV dose of [erg] into [rad]. In spite of the fact that the calculation methods are theoretically already well known, the experimental determination of the absorbed energy dose, in particular the absorption factors, was complicated by the morphological structure of the pollen. The total-irradiation experiments showed that the stimulation and inhibition of pollen tube growth is highly dependent on the dose/dose rate region chosen. Stimulation is highly dependent on the dose rate after UV irradiation as well as after exposure to ionizing radiation. When the dose rates are very small, the values are practically the same as in non-irradiated controls; with increasing doses rate, stimulation increases, whereas at very high dose rates only growth inhibition is observed. After exposure to ionizing radiation, the quantum energy or wavelength of the radiation has no effect on tube growth; after UV irradiation, on the other hand, there is hardly any stimulation at short wavelengths. As these observations were not sufficient for drawing conclusions on the site of the stimulatory action, partial UV exposure with separate irradiation of the two nuclei and the cytoplasm was also carried out. Stimulation was found in each of the three irradiation sites; although nuclei and cytoplasma react differently and also differ in the initial reaction stages, there is always an anhancement of pollen tube growth. These findings are compared with some of the current hypotheses for an explanation of the stimulatory effect. (orig.) [de

  4. Preliminary results relating to gamma irradiations of the pollen in the pineapple (Ananas comosus (L.) Merr)

    International Nuclear Information System (INIS)

    Benaga, R.; Vicedo, L.; Isidron, M.; Arias, E.; Campanioni, L.; Fernandez, J.; Castillo, E.; Romero, M.

    1993-01-01

    As a way to know the radiosensitivity of the pollen of pineapple, in order to get to know haploid plants, the anthers of red Espanola of the type Pinarena and smooth Cayena from the Serrana (Ciego de Avila) were exposed to 60C o gamma radiations in the irradiator at CENSA, with fractional doses ranging from zero to 5KGy. The percentage of germination and length pollinic tube is analysed in vitro; a decrease in the above mentioned parameters is observed, with the main doses in the two cultures although red Espanola showed a slight recovery at doses of 3 and 4KGy as well as the major values of germination of the pollen

  5. Gene transfer in Nicotiana rustica by means of irradiated pollen II. Cytogenetical consequences

    International Nuclear Information System (INIS)

    Werner, C.P.; Dunkin, I.M.; Cornish, M.A.; Jones, G.H.

    1984-01-01

    Pollen from Nicotiana paniculata and the V12 variety of N. rustica was irradiated with a range of high doses of gamma-rays up to 100 Krads. Both kinds of pollen were used to pollinate the V27 variety of N. rustica. Radiation treatments above 30 Krads gave no viable seed. A cytological examination of the M 1 progeny from the 20 Krad treatments of both crosses revealed conventional radiation damage in the form of losses of whole chromosomes and parts of chromosomes, and rearrangements. The plants possessed hybrid or aberrantly hybrid phenotypes. It was concluded that they were the products of a conventional fertilisation mechanism rather than the gene transfer mechanism proposed by Pandey (1980). The expression of mutational damage can probably account for most of the maternal trends observed in the intervarietal M 2 of N. rustica examined previously, although post-meiotic selection may also play a role. (author)

  6. Effects of gamma irradiation and ozone treatment on microbial decontamination and fatty acid compositions of aloe and pollen powders

    International Nuclear Information System (INIS)

    Yook, H.S.; Chung, Y.J.; Kim, J.O.; Kwon, O.J.; Byun, M.W.

    1997-01-01

    The comparative effects of gamma irradiation and ozone treatment on the microbial inactivation and fatty acid composition were investigated for improving hygienic quality of aloe and pollen powders. Gamma irradiation at 10 kGy resulted in sterilizing total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the microorganisms of aloe and pollen powders. The compositions of fatty acid were not significantly changed by gamma irradiation up to 10 kGy. However, ozone treatment markedly decreased unsaturated fatty acids by approximately 20-80% in contents, whereas it significantly increased saturated fatty acids (p<0.05)

  7. In vitro germination and the effect of acute gamma irradiation on pollen of Pinus patula Schiede et Deppe

    International Nuclear Information System (INIS)

    Kapoor, M.L.; Dobriyal, N.D.

    1980-01-01

    In-vitro study revealed that the best medium for germinating P. patula pollen was 12,5% Sucrose with 0.001% Boron in 2% agar medium. After gamma irradiation the LD-50 based on pollen germination and germination energy index was 1.174 kr and 1.148 kr respectively. Pollen was viable on the 90th day when used after storing at 10 0 C in desiccator. Gamma doses for haploid breeding and mutation breeding are suggested. ANOVA showed that differences between the different media used for germination and gamma-ray doses were highly significant. (orig.) [de

  8. Pollination with heavily irradiated pollen in Nicotiana: induced parthenogenesis and embryological study

    International Nuclear Information System (INIS)

    Musial, K.; Przywara, L.

    1999-01-01

    Nicotiana crosses were pollinated in situ and in vitro with heavily irradiated pollen (500, 700, 1000 Gy) to induce parthenogenesis and to study the development of embryo and endosperm. Haploids were obtained after in situ pollination only; however, parthenogenetic proembryos occurred also after in vitro pollination. It was demonstrated that ovule culture following pollination offers a better chance to produce haploids than undisturbed pollination does. Pollination with irradiated pollen (PwIP) stron gly decreased the number of endosperm cells and the size of embryo sacs, and it affected the development of embryos; no significant differences between applied irradiation doses were found. Ovules with endosperm only, embryo only, and with both embryo and endosperm were observed. The most frequent were the ovules with endosperm only, the rarest with embryo only. A small amount of storage products occurred in the endosperm cells. The diploid chromosome number counted in the endosperm produced after PwIP points to their origin without fertilization. An interesting phenomenon observed after PwIP was vigorous growth of endothelium. (author)

  9. Apparatus for irradiation with electron beam

    International Nuclear Information System (INIS)

    Uehara, K.; Ito, A.; Nishimune, K.; Fujita, K.

    1976-01-01

    An irradiation apparatus with high energy electrons is disclosed in which a wire shaped or linear object to be irradiated is moved back and forth many times under an electron window so as to irradiate it with an electron beam. According to one feature of the invention, an electron beam, which leaks through gaps between the objects to be irradiated or which penetrates the objects to be irradiated, is reversed by a magnetic field approximately perpendicular to the scanning face of the electron beam by means of a magnet which is disposed under the objects to be irradiated, and the reversed electron beam is thereby again applied to the objects to be irradiated. A high utilization rate of the electron beam is accomplished, and the objects can be thereby uniformly irradiated with the electron beam. 4 claims, 6 drawing figures

  10. Is pollen morphology of Salix polaris affected by enhanced UV-B irradiation? Results from a field experiment in high Arctic tundra

    NARCIS (Netherlands)

    Yeloff, Dan; Blokker, Peter; Boelen, Peter; Rozema, Jelte

    2008-01-01

    This study tested the hypothesis that the thickness of the pollen wall will increase in response to enhanced UV-B irradiation, by examining, the effect of enhanced UV-B irradiance on the pollen morphology of Sali-v polaris Wahlem. grown in a Field experiment on the Arctic tundra of Svalbard.

  11. Electron accelerator technology research in food irradiation

    International Nuclear Information System (INIS)

    Jin Jianqiao; Ye Mingyang; Zhang Yue; Yang Bin; Xu Tao; Kong Xiangshan

    2014-01-01

    Electronic accelerator was applied to instead of cobalt sources for food irradiation, to keep food quality and to improve the effect of the treatment. Appropriate accelerator parameters lead to optimal technique. The irradiation effect is associated with the relationship between uniformity and irradiating speed, the effect of cargo size on radiation penetration, as well as other factors that affect the irradiation effects. Industrialization of electron accelerator irradiation will be looked to the future. (authors)

  12. Fruit and seed characteristics of diploid seedless watermelon (citrullus lanatas) cultivars produced by soft-X-irradiated pollen

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, Keita; Morishita, Masami [National Research Insti. of Vegetables, Ornamental Plants and Tea, Fukuoka (Japan). Kurume Branch

    2000-11-01

    We compared the differences in number of seeds, size of normal and empty seeds, and fruit quality of seedless fruit induced by soft- X- irradiated pollen to determine which cultivars are best suited for breeding and producing high quality seedless watermelon. Two wild types, eleven Japanese, one Chinese, and three American watermelon cultivars were studied. We also observed the effect of soft- X- rays on pollen germination and elongation of the pollen tube. The germination rates of pollen treated with 1000 to 2000 Gy of soft-X-ray were almost the same as those of the control, whereas the rate was significantly reduced at 3000 Gy. Soft-X- irradiated pollen germinated on a stigma, and the pollen tube elongated in the embryo sac. Watermelon fruit pollinated with pollen irradiated with 800 Gy of soft-X-ray had no normal seeds but only empty ones. To delineate the varietal differences by the number of empty seeds and seed size in seedless fruit, wild types, Japanese, Chinese, and American watermelon cultivars were investigated. The number and size of empty seeds varied among cultivars. A low correlation (r=0.272) existed between the total number of seeds in the control fruit and the number of empty seeds in the seedless fruit. Whereas, a high correlation (seed length: r=0.943, P<0.001, seed width: r=0.883, P < 0.001) was found between the size of normal seeds in control fruit and empty seeds in seedless fruit. Diploid seedless fruit was similar to control fruit in size, shape, color, rind thickness, sugar content, and days from pollination to maturity. (author)

  13. Fruit and seed characteristics of diploid seedless watermelon (citrullus lanatas) cultivars produced by soft-X-irradiated pollen

    International Nuclear Information System (INIS)

    Sugiyama, Keita; Morishita, Masami

    2000-01-01

    We compared the differences in number of seeds, size of normal and empty seeds, and fruit quality of seedless fruit induced by soft- X- irradiated pollen to determine which cultivars are best suited for breeding and producing high quality seedless watermelon. Two wild types, eleven Japanese, one Chinese, and three American watermelon cultivars were studied. We also observed the effect of soft- X- rays on pollen germination and elongation of the pollen tube. The germination rates of pollen treated with 1000 to 2000 Gy of soft-X-ray were almost the same as those of the control, whereas the rate was significantly reduced at 3000 Gy. Soft-X- irradiated pollen germinated on a stigma, and the pollen tube elongated in the embryo sac. Watermelon fruit pollinated with pollen irradiated with 800 Gy of soft-X-ray had no normal seeds but only empty ones. To delineate the varietal differences by the number of empty seeds and seed size in seedless fruit, wild types, Japanese, Chinese, and American watermelon cultivars were investigated. The number and size of empty seeds varied among cultivars. A low correlation (r=0.272) existed between the total number of seeds in the control fruit and the number of empty seeds in the seedless fruit. Whereas, a high correlation (seed length: r=0.943, P<0.001, seed width: r=0.883, P < 0.001) was found between the size of normal seeds in control fruit and empty seeds in seedless fruit. Diploid seedless fruit was similar to control fruit in size, shape, color, rind thickness, sugar content, and days from pollination to maturity. (author)

  14. Techunique to depress seeds formation in small sized watermelon [Citrullus lanatus] by using pollen irradiated with soft X-rays

    International Nuclear Information System (INIS)

    Tajiri, K.; Ishida, T.

    2005-01-01

    Pollen irradiated soft X-rays is effective to depress seed formation in fruits of watermelon. In this investigation, it's effect are disucussed on some varieties of small sized water melon on semi-focing and retarding culture. Results are followed; The radiation of soft X-rays to pollen gave less seeds formation in fruits of wide varieties on both cropping season. The fruit setting was normal on the case of using irradiated pollen, and the growth and quality of fruits were equal or better than that of triploid variety of watermelon. The size of emty seeds remained in fruit was big in the variety whitch had originally big size seeds. On variety comparison under two cropping season. 'hitorijime' , 'summerkids' and ' himekannsen' showed excellent quality and less-formation of residual seeds in their fruits. To determine optimum level of soft X-rays irradiation, three levels of irradiation intensity were te sted. Irradiation intensity to pollen did not affect to the furit setting and the growth of fruit. B ut sugarcontent in fruit was generally higher than that of no-treatment. The effect of radiation int ensity to formation of seeds was different on cropping season. The optimum intensity was 1600Gy on r etarding culture. On semi-forcing culture, depressive effect on seeds formation by soft X-rays irrad iation was incresed as the increment of irradiation intensity between 0 to 800Gy, but irradiation av obe 1600Gy gave opposite result. Then optimum irradiation level is 800-1200Gy

  15. Influence of Gamma Irradiation on Microbial Quality, Biological Properties and Some Chemical Compositions of Propolis and Bee Pollen In Egypt

    International Nuclear Information System (INIS)

    Eltablawy, S.Y.

    2012-01-01

    Propolis and bee pollen may be subjected to microbial contamination as a result of handling and storage, so, the current study was conducted to evaluate the microbial quality and quantity of Egyptian propolis and pollen and to study microbial contamination, antimicrobial activity, antioxidant activity and some chemical properties as amino acid composition and mineral content of irradiated and non-irradiated tested samples.The results showed that most samples were of unsatisfactory microbiological quality where the total bacterial and mold and yeast counts ranged between 6.6x10-6x10 6 CFU/g and 1.2 x 10 3 -3.7x10 3 CFU/g, respectively. Agar disk diffusion method was used for in vitro antimicrobial evaluation of propolis and pollen using water and 70% ethanolic extract against four gram positive, three gram negative bacteria and one yeast pathogens. The results exhibited that ethanolic extract has effective antibacterial activities than water extract. The free radical-scavenging activity of 70% ethanolic extract of the tested samples was determined using 1,1-diphenyl-2-picryl hydrazyl (DPPH). Pollen ethanolic extract showed higher antioxidant activity than propolis ethanolic extract. Amino acid profile of 70% ethanolic extract was determined. The results of the analysis showed the predominant amino acids in propolis and pollen were cystine and leucine, respectively. Mineral analysis of the tested samples was carried out by atomic absorption. The tested minerals were higher in pollen than in propolis except manganese and selenium. Propolis and pollen heavily bacterial and mold contaminated samples were subjected to increasing doses of gamma radiation (1-5 kGy). Exposure to 4 kGy was sufficient for microbial decontamination or reducing the count less than 10 CFU/g with no detectable effect on their antimicrobial activity. The same irradiation dose showed variable effects on amino acids and mineral content of the tested samples. Propolis and pollen have pharmacological

  16. Use of irradiated pollen for differential gene transfer in wheat (Triticum aestivum)

    Energy Technology Data Exchange (ETDEWEB)

    Snape, J.W.; Parker, B.B.; Simpson, E.; Ainsworth, C.C.; Payne, P.I.; Law, C.N.

    1983-01-01

    The use of irradiated pollen to bring about limited gene transfer in wheat has been investigated. Doses of X-rays of 2Kr, 3Kr and 5Kr were used to generate M/sub 1/ progeny between maternal and paternal genotypes differing in quantitative and major gene characters. Cytological studies of M/sub 1/ plants revealed hybrids with widespread aneuploidy and structural rearrangements in the paternal genome. These effects resulted in phenotypic variation between M/sub 1/ progeny and complex multivalent formation at meiosis. All M/sub 1/ plants at the 5Kr and 3Kr doses were sterile and all but 2 plants at the 2Kr dose. Studies of the two M/sub 2/ families from these plants revealed disturbances in genotype frequencies for some of the marker loci with an excess of maternal homozygotes and a deficit of paternal homozygotes. This was also reflected in a more maternal appearance for quantitative characters. These results are interpreted as showing that irradiation damage to the paternal genome in M/sub 1/ plants results in the differential transmission of maternal alleles.

  17. The use of irradiated pollen for differential gene transfer in wheat (Triticum aestivum)

    International Nuclear Information System (INIS)

    Snape, J.W.; Parker, B.B.; Simpson, E.; Ainsworth, C.C.; Payne, P.I.; Law, C.N.

    1983-01-01

    The use of irradiated pollen to bring about limited gene transfer in wheat has been investigated. Doses of X-rays of 2Kr, 3Kr and 5Kr were used to generate M 1 progeny between maternal and paternal genotypes differing in quantitative and major gene characters. Cytological studies of M 1 plants revealed hybrids with widespread aneuploidy and structural rearrangements in the paternal genome. These effects resulted in phenotypic variation between M 1 progeny and complex multivalent formation at meiosis. All M 1 plants at the 5Kr and 3Kr doses were sterile and all but 2 plants at the 2Kr dose. Studies of the two M 2 families from these plants revealed disturbances in genotype frequencies for some of the marker loci with an excess of maternal homozygotes and a deficit of paternal homozygotes. This was also reflected in a more maternal appearance for quantitative characters. These results are interpreted as showing that irradiation damage to the paternal genome in M 1 plants results in the differential transmission of maternal alleles. (orig.)

  18. Dose distributions in electron irradiated plastic tubing

    International Nuclear Information System (INIS)

    Miller, A.; Pederson, W.B.

    1981-01-01

    Plastic tubes have been crosslinked by irradiation at a 10 MeV linear electron accelerator and at a 400 keV DC electron accelerator at different irradiation geometries. The diameter of the different tubes was 20, 33 and 110 millimeters. Dose distributions have been measured with thin radiochromic dye films, indicating that in all cases irradiation from two sides is a necessary and sufficient condition for obtaining a satisfactory dose distribution. (author)

  19. Accuracy and Consistency of Grass Pollen Identification by Human Analysts Using Electron Micrographs of Surface Ornamentation

    Directory of Open Access Journals (Sweden)

    Luke Mander

    2014-08-01

    Full Text Available Premise of the study: Humans frequently identify pollen grains at a taxonomic rank above species. Grass pollen is a classic case of this situation, which has led to the development of computational methods for identifying grass pollen species. This paper aims to provide context for these computational methods by quantifying the accuracy and consistency of human identification. Methods: We measured the ability of nine human analysts to identify 12 species of grass pollen using scanning electron microscopy images. These are the same images that were used in computational identifications. We have measured the coverage, accuracy, and consistency of each analyst, and investigated their ability to recognize duplicate images. Results: Coverage ranged from 87.5% to 100%. Mean identification accuracy ranged from 46.67% to 87.5%. The identification consistency of each analyst ranged from 32.5% to 87.5%, and each of the nine analysts produced considerably different identification schemes. The proportion of duplicate image pairs that were missed ranged from 6.25% to 58.33%. Discussion: The identification errors made by each analyst, which result in a decline in accuracy and consistency, are likely related to psychological factors such as the limited capacity of human memory, fatigue and boredom, recency effects, and positivity bias.

  20. Production of haploid plant of 'Banpeiyu' pummelo [Citrus maxima (Burm.) Merr.] by pollination with soft X-ray-irradiated pollen

    International Nuclear Information System (INIS)

    Yahata, Masaki; Yasuda, Kiichi; Kunitake, Hisato; Nagasawa, Kohji; Harusaki, Seiichi; Komatsu, Haruki

    2010-01-01

    To induce haploid plants in Citrus maxima (Burm.) Merr. 'Banpeiyu', we evaluated the effect of pollination with soft X-ray-irradiated pollen on fruit set and seed development, and carried out ovule culture. When 'Banpeiyu' pummelo pistils were pollinated with X-ray-irradiated pollen of 'Fukuhara' sweet orange [C. sinensis (L.) Osbeck], the exposure doses affected the fruit set. The number of seeds per fruit was also affected by the exposure dose, and tended to decrease as the dose increased; however, all developed seeds obtained from these crosses were diploid. In the ovule culture of 'Banpeiyu' pummelo, six embryoids shown haploidy were obtained in all treatments. One haploid plantlet with 9 chromosomes was regenerated from an embryoid in a culture of ovules established 40 days after pollination with 400 Gray (Gy)-irradiated pollen of 'Tosa-buntan' pummelo (C. maxima). This haploid was suggested to be derived from 'Banpeiyu' pummelo by random amplified polymorphic DNA (RAPD) and cleaved amplified polymorphic sequence (CAPS) analysis. (author)

  1. A novel approach for honey pollen profile assessment using an electronic tongue and chemometric tools

    International Nuclear Information System (INIS)

    Dias, Luís G.; Veloso, Ana C.A.; Sousa, Mara E.B.C.; Estevinho, Letícia; Machado, Adélio A.S.C.

    2015-01-01

    Nowadays the main honey producing countries require accurate labeling of honey before commercialization, including floral classification. Traditionally, this classification is made by melissopalynology analysis, an accurate but time-consuming task requiring laborious sample pre-treatment and high-skilled technicians. In this work the potential use of a potentiometric electronic tongue for pollinic assessment is evaluated, using monofloral and polyfloral honeys. The results showed that after splitting honeys according to color (white, amber and dark), the novel methodology enabled quantifying the relative percentage of the main pollens (Castanea sp., Echium sp., Erica sp., Eucaliptus sp., Lavandula sp., Prunus sp., Rubus sp. and Trifolium sp.). Multiple linear regression models were established for each type of pollen, based on the best sensors' sub-sets selected using the simulated annealing algorithm. To minimize the overfitting risk, a repeated K-fold cross-validation procedure was implemented, ensuring that at least 10–20% of the honeys were used for internal validation. With this approach, a minimum average determination coefficient of 0.91 ± 0.15 was obtained. Also, the proposed technique enabled the correct classification of 92% and 100% of monofloral and polyfloral honeys, respectively. The quite satisfactory performance of the novel procedure for quantifying the relative pollen frequency may envisage its applicability for honey labeling and geographical origin identification. Nevertheless, this approach is not a full alternative to the traditional melissopalynologic analysis; it may be seen as a practical complementary tool for preliminary honey floral classification, leaving only problematic cases for pollinic evaluation. - Highlights: • Honey's floral origin labeling is a legal requirement. • Melissopalynology analysis usually used to evaluate pollens profile is laborious. • A novel E-tongue based approach is applied to assess pollens relative

  2. A novel approach for honey pollen profile assessment using an electronic tongue and chemometric tools

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Luís G., E-mail: ldias@ipb.pt [Escola Superior Agrária, Instituto Politécnico de Bragança, Campus Santa Apolónia, 5301-855 Bragança (Portugal); CQ-VR, Centro de Química – Vila Real, University of Trás-os-Montes e Alto Douro, Apartado 1013, 5001-801 Vila Real (Portugal); Veloso, Ana C.A. [Instituto Politécnico de Coimbra, ISEC, DEQB, Rua Pedro Nunes, Quinta da Nora, 3030-199 Coimbra (Portugal); CEB-Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Sousa, Mara E.B.C.; Estevinho, Letícia [CIMO-Escola Superior Agrária, Instituto Politécnico de Bragança, Campus Santa Apolónia, 5301-855 Bragança (Portugal); Machado, Adélio A.S.C. [LAQUIPAI – Laboratório de Química Inorgânica Pura e de Aplicação Interdisciplinar, Departamento de Química, Faculdade de Ciências da, Universidade do Porto, Rua Campo Alegre n°. 687, 4169-007 Porto (Portugal); and others

    2015-11-05

    Nowadays the main honey producing countries require accurate labeling of honey before commercialization, including floral classification. Traditionally, this classification is made by melissopalynology analysis, an accurate but time-consuming task requiring laborious sample pre-treatment and high-skilled technicians. In this work the potential use of a potentiometric electronic tongue for pollinic assessment is evaluated, using monofloral and polyfloral honeys. The results showed that after splitting honeys according to color (white, amber and dark), the novel methodology enabled quantifying the relative percentage of the main pollens (Castanea sp., Echium sp., Erica sp., Eucaliptus sp., Lavandula sp., Prunus sp., Rubus sp. and Trifolium sp.). Multiple linear regression models were established for each type of pollen, based on the best sensors' sub-sets selected using the simulated annealing algorithm. To minimize the overfitting risk, a repeated K-fold cross-validation procedure was implemented, ensuring that at least 10–20% of the honeys were used for internal validation. With this approach, a minimum average determination coefficient of 0.91 ± 0.15 was obtained. Also, the proposed technique enabled the correct classification of 92% and 100% of monofloral and polyfloral honeys, respectively. The quite satisfactory performance of the novel procedure for quantifying the relative pollen frequency may envisage its applicability for honey labeling and geographical origin identification. Nevertheless, this approach is not a full alternative to the traditional melissopalynologic analysis; it may be seen as a practical complementary tool for preliminary honey floral classification, leaving only problematic cases for pollinic evaluation. - Highlights: • Honey's floral origin labeling is a legal requirement. • Melissopalynology analysis usually used to evaluate pollens profile is laborious. • A novel E-tongue based approach is applied to assess pollens

  3. Green coffee decontamination by electron beam irradiation

    International Nuclear Information System (INIS)

    Nemtanu, Monica R.; Brasoveanu, Mirela; Grecu, Maria Nicoleta; Minea, R.

    2005-01-01

    Microbiological load of green coffee is a real problem considering that it is extremely sensitive to contamination. Irradiation is a decontamination method for a lot of foodstuffs, being a feasible, very effective and environment friendly one. Beans and ground green coffee were irradiated with electron beams up to 40 kGy. Microbial load, rheological behavior, electron paramagnetic resonance (EPR) and visible spectroscopy were carried out. The results show that electron beam irradiation of green coffee could decontaminate it without severe changes in its properties

  4. Structural changes induced by electron irradiation

    International Nuclear Information System (INIS)

    Koike, J.; Pedraza, D.F.

    1993-01-01

    Highly oriented pyrolytic graphite was irradiated at room temperature with 300 kV electrons. Transmission electron microscopy and electron energy loss spectroscopy were employed to study the structural changes produced by irradiation. The occurrence of a continuous ring intensity in the selected area diffraction (SAD) pattern obtained on a specimen irradiated with the electron beam parallel to the c-crystallographic axis indicated that microstructural changes had occurred. However, from the SAD pattern obtained for the specimens tilted relative to the irradiation direction, it was found that up to a fluence of 1.1x10 27 e/m 2 graphite remained crystalline. An SAD pattern of a specimen irradiated with the electron beam perpendicular to the c-axis confirmed the persistence of crystalline order. High resolution electron microscopy showed that ordering along the c-axis direction remained. A density reduction of 8.9% due to irradiation was determined from the plasmon frequency shift. A qualitative model is proposed to explain these observations. A new determination of the threshold displacement energy, Ed, of carbon atoms in graphite was done by examining the appearance of a continuous ring in the SAD pattern at various electron energies. A value of 30 eV was obtained whether the incident electron beam was parallel or perpendicular to the c-axis, demonstrating that Ed is independent of the displacement direction

  5. Cytogenetical investigations on fertilization, embriogenesis and fruit formation by irradiated pollen

    International Nuclear Information System (INIS)

    Dryanovska, O.

    1981-01-01

    The mechanism of fertilization pollination with gamma-irradiated pollen (1-500 kR) in plants of various double fertilization: Crepis (Nicotiana tabacum, Lycopersicum esculentum, Solanum melongena, Ornithogalum gramminifolium, Melandrium rubrum) type, Lilium (Lilium speciosum) type, and Trandescantia (Tradescantia paludosa) type was studied, along with the opportunity of its modification, embryogenesis and fruit and seed formation. In the Crepis type, depending on the disturbances of male chromatin, fertilization manifested itself as: 1) normal karyogamy with decondensation of male chromatin and the formation of supplementary nucleoli and further development of embryo and endosperm (1-500 kR); 2) karyogamy without decondensation and functioning of the male chromatin (1-500 kR); 3) karyogamy or sticking the male chromatin to the nuclei of the female sex cells, stimulating the development of the ovule, embryo, and endosperm (50-500 kR); 4) sticking the highly pycnotized male chromatin to the nuclei of the female sex cells without evidence of zygote and endosperm function and further development (50-500 kR). In the Lilium type modification of fertilization was manifested by: 1) normal karyogamy with developing diploid embryos and pentaploid endosperm with aberrations (1-20 kK); 2) sticking the male chromatin to the nuclei of the female sex cells and stimulation of their development (50-500 kR). In the Trandescantia type the irradiated male chromatin modified fertilization as: 1) karyogamy with spermia having fragments, two spermia connected by a bridge or with a generative nucleus with aberrations (1-50 kR); 2) karyogamy without developing the female sex nuclei (10-500kR); 3) karyogamy or sticking the male chromatin to the female sex cell nuclei and stimulation of their development (10-500 kR); 4) sticking the male chromatin with no stimulating effect (10-500 kR). (author)

  6. Cytogenetical investigations on fertilization, embriogenesis and fruit formation by irradiated pollen. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dryanovska, O.

    1981-01-01

    The mechanism of fertilization pollination with gamma-irradiated pollen (1-500 kR) in plants of various double fertilization: Crepis (Nicotiana tabacum, Lycopersicum esculentum, Solanum melongena, Ornithogalum gramminifolium, Melandrium rubrum) type, Lilium (Lilium speciosum) type, and Trandescantia (Tradescantia paludosa) type was studied, along with the opportunity of its modification, embryogenesis and fruit and seed formation. In the Crepis type, depending on the disturbances of male chromatin, fertilization manifested itself as: 1) normal karyogamy with decondensation of male chromatin and the formation of supplementary nucleoli and further development of embryo and endosperm (1-500 kR); 2) karyogamy without decondensation and functioning of the male chromatin (1-500 kR); 3) karyogamy or sticking the male chromatin to the nuclei of the female sex cells, stimulating the development of the ovule, embryo, and endosperm (50-500 kR); 4) sticking the highly pycnotized male chromatin to the nuclei of the female sex cells without evidence of zygote and endosperm function and further development (50-500 kR). In the Lilium type modification of fertilization was manifested by: 1) normal karyogamy with developing diploid embryos and pentaploid endosperm with aberrations (1-20 kK); 2) sticking the male chromatin to the nuclei of the female sex cells and stimulation of their development (50-500 kR). In the Trandescantia type the irradiated male chromatin modified fertilization as: 1) karyogamy with spermia having fragments, two spermia connected by a bridge or with a generative nucleus with aberrations (1-50 kR); 2) karyogamy without developing the female sex nuclei (10-500kR); 3) karyogamy or sticking the male chromatin to the female sex cell nuclei and stimulation of their development (10-500 kR); 4) sticking the male chromatin with no stimulating effect (10-500 kR).

  7. Electron microscopy of boron carbide before and after electron irradiation

    International Nuclear Information System (INIS)

    Stoto, T.; Zuppiroli, L.; Beauvy, M.; Athanassiadis, T.

    1984-06-01

    The microstructure of boron carbide has been studied by electron microscopy and related to the composition of the material. After electron irradiations in an usual transmission electron microscope and in a high voltage electron microscope at different temperatures and fluxes no change of these microstructures have been observed but a sputtering of the surface of the samples, which has been studied quantitatively [fr

  8. Electron spin resonance identification of irradiated fruits

    International Nuclear Information System (INIS)

    Raffi, J.J.; Agnel, J.-P.L.

    1989-01-01

    The electron spin resonance spectrum of achenes, pips, stalks and stones from irradiated fruits (stawberry, raspberry, red currant, bilberry, apple, pear, fig, french prune, kiwi, water-melon and cherry) always displays, just after γ-treatment, a weak triplet (a H ∼30 G) due to a cellulose radical; its left line (lower field) can be used as an identification test of irradiation, at least for strawberries, raspberries, red currants or bilberries irradiated in order to improve their storage time. (author)

  9. High energy electron irradiation of flowable materials

    International Nuclear Information System (INIS)

    Offermann, B.P.

    1975-01-01

    In order to efficiently irradiate a flowable material with high energy electrons, a hollow body is disposed in a container for the material and the material is caused to flow in the form of a thin layer across a surface of the body from or to the interior of the container while the material flowing across the body surface is irradiated. (U.S.)

  10. Food irradiation by low energy electrons

    International Nuclear Information System (INIS)

    Bird, J.R.

    1985-01-01

    For some special cases, the use of low energy electrons has advantages over the use of gamma-rays or higher energy electrons for the direct irradiation of food. These advantages arise from details of the interaction processes which are responsible for the production of physical, chemical and biological effects. Factors involved include depth of penetration, dose distribution, irradiation geometry, the possible production of radioactivity and costs

  11. Apparatus for electron beam irradiation of objects

    International Nuclear Information System (INIS)

    Dmitriev, S.P.; Ivanov, A.S.; Sviniin, M.P.; Fedotov, M.T.

    1984-01-01

    This patent provides an apparatus for electron beam irradiation of objects, comprising a shaper of a ribbon-shaped electron beam and a deflecting electromagnet having a frame-type magnetic circuit and used to direct said electron beam onto an irradiated object substantially at an angle of 90 degrees. The deflecting electromagnet has two poles extended over the width of the irradiated object and comprises two windings embracing said poles and connected to a d.c. source. The deflecting electromagnet is arranged in such a manner that the trajectories of the electrons at an area from the shaper to the electromagnet are inclined to the plane of the frame of its magnetic circuit

  12. Electron irradiation of dry food products

    International Nuclear Information System (INIS)

    Gruenewald, Th.

    1983-01-01

    The interest of the industrial food producer is increasing in having the irradiation facility installed in the food processing chain. The throughput of the irradiator should be high and the residence time of the product in the facility should be short. These conditions can be accomplished by electron irradiators. To clarify the irradiation conditions spices taken out of the industrial process, food grade salt, sugar, and gums as models of dry food products were irradiated. With a radiation dose of 10 kGy microbial load can be reduced on 10**4 microorganisms/g. The sensory properties of the spices were not changed in an atypical way. For food grade salt and sugar changes of colour were observed which are due to lattice defects or initiated browning. The irradiation of several gums led only in some cases to an improvement of the thickness properties in the application below 50 deg C, in most cases the thickness effect was reduced. The products were packaged before irradiation. But it would be possible also to irradiate the products without packaging moving the product through the irradiation field in a closed conveyor system. (author)

  13. Electron irradiation of dry food products

    Energy Technology Data Exchange (ETDEWEB)

    Gruenewald, Th [Bundesbahn-Zentralamt, Minden (Germany, F.R.)

    1983-01-01

    The interest of the industrial food producer is increasing in having the irradiation facility installed in the food processing chain. The throughput of the irradiator should be high and the residence time of the product in the facility should be short. These conditions can be accomplished by electron irradiators. To clarify the irradiation conditions spices taken out of the industrial process, food grade salt, sugar, and gums as models of dry food products were irradiated. With a radiation dose of 10 kGy microbial load can be reduced on 10**4 microorganisms/g. The sensory properties of the spices were not changed in an atypical way. For food grade salt and sugar changes of colour were observed which are due to lattice defects or initiated browning. The irradiation of several gums led only in some cases to an improvement of the thickness properties in the application below 50 deg C, in most cases the thickness effect was reduced. The products were packaged before irradiation. But it would be possible also to irradiate the products without packaging moving the product through the irradiation field in a closed conveyor system.

  14. Spectroscopy of electron irradiated polymers in electron microscope

    International Nuclear Information System (INIS)

    Faraj, S.H.; Salih, S.M.

    1981-01-01

    The damage induced by energetic electrons in the course of irradiation of polymers in a transmission electron microscope was investigated spectroscopically. Damage on the molecular level has been detected at very low exposure doses. These effects have been induced by electron doses less than that received by the specimen when it is situated at its usual place of the specimen stage in the electron microscope by a factor of 1,000. (author)

  15. Irradiation of Gemstones using Electron Beam

    International Nuclear Information System (INIS)

    Sarada Idris; Mohd Suhaimi Jusoh; Siti Aiasah Hashim

    2011-01-01

    Gemstone irradiation treatment using radiation is one of the studies conducted in the ALURTRON. The purpose of radiation is to study the effects of radiation on the gems. Through studies conducted on freshwater pearls and stones such as Topaz, Kunzite, TOURMALINE, Aquamarine, Quartz and so on, electron beam irradiation method can highlight the jewel colors but also to reduce the effects of haze on gemstones. The dose of radiation used is 25 kGy to 200 kGy. (author)

  16. MCNPX calculations for electron irradiated semiconductor detectors

    International Nuclear Information System (INIS)

    Sedlackova, K.; Necas, V.; Sagatova, A.; Zatko, B.

    2014-01-01

    This study aimed to treat some practical problems of (not only) semiconductor material irradiation by high energy electron beam using MCNPX simulation code. The relation between the absorbed dose and the fluency was found and the energy distribution of electron flux density was simulated on the top and back side of 270 μm thick GaAs, SiC and Si detectors. Furthermore, the dose depth profiles were calculated for GaAs, SiC and Si materials irradiated by 4 and 5 MeV electron beams. For the GaAs detector, a very good agreement with the experiment was shown. To match the absolute values of the absorbed dose with experimentally obtained values, the electron source emissivity has to be determined in relation to the electron beam setting parameters. (authors)

  17. Electron-irradiation-induced phase transformation in alumina

    International Nuclear Information System (INIS)

    Chen, C.L.; Arakawa, K.; Lee, J.-G.; Mori, H.

    2010-01-01

    In this study, electron-irradiation-induced phase transformations between alumina polymorphs were investigated by high-resolution transmission electron microscopy. It was found that the electron-irradiation-induced α → κ' phase transformation occurred in the alumina under 100 keV electron irradiation. It is likely that the knock-on collision between incident electrons and Al 3+ cations is responsible for the occurrence of electron-irradiation-induced phase transformation from α-alumina to κ'-alumina.

  18. Electron beam irradiation technology for environmental conservation

    International Nuclear Information System (INIS)

    Tokunaga, Okihiro; Arai, Hidehiko; Hashimoto, Shoji

    1992-01-01

    This paper reviews research and development of application of electron beam (EB) irradiation technology for treatment of flue gas and waste water, and for disinfection of sewage sludge. Feasibility studies on EB purification of flue gases have been performed with pilot-scale experiments in Japan, the USA and Germany, and is being carried out in Poland for flue gases from iron-sintering furnaces or coal burning boilers. Based on results obtained by experiments using simulated flue gas, pilot scale test for treatment of flue gas of low-sulfur containing coal combustion has recently started in Japan. Organic pollutants in waste water and ground water have been found to be decomposed by EB irradiation. Synergetic effect of EB irradiation and ozone addition was found to improve the decomposition efficiency. Electron beam irradiation technology for disinfection of water effluent from water treatment plants was found to avoid formation of chlorinated organic compounds which are formed in using chlorine. Efficient process for composting of sewage sludge disinfected by EB irradiation has been developed by small scale and pilot scale experiments. In the new process, disinfection by EB irradiation and composing can be done separately and optimum temperature for composting can be, therefore, selected to minimize period of composting. (author)

  19. AECL IMPELA electron beam industrial irradiators

    International Nuclear Information System (INIS)

    Labrie, J.P.; Drewell, N.H.; Ebrahim, N.A.; Lawrence, C.B.; Mason, V.A.; Ungrin, J.; White, B.F.

    1989-01-01

    A family of industrial irradiators is being developed by AECL to cover an electron-beam energy range from 5 to 18 MeV at beam powers between 20 and 250 kW. The IMPELA family of irradiators is designed for push button, reliable operation. The major irradiator components are modular, allowing for later upgrades to meet increased demands in either electron or X-ray mode. Interface between the control system, irradiator availability and dose quality assurance is in conformance with the most demanding specifications. The IMPELA irradiators use a klystron-driven, standing-wave, L-band accelerator structure with direct injection from a rugged, triode electron gun. Direct control of the accelerating field during the beam pulse ensures constant output beam energy, independent of beam power. The first member of the family, the IMPELA 10/50 (10 MeV, 50 kW), is in the final stages of assembly at Chalk River Nuclear Laboratories. The IMPELA 10/50 is constructed around a 3.25 m long, high-power-capacity accelerator structure operated at a duty factor of 5%. Beam loading exceeds 60%. The rf power is provided by a 2 MW/150 kW modulated-anode klystron protected from load mismatches by a circulator. This prototype will be used to demonstrate the reliability and dose uniformity targets of the IMPELA family. Full beam operation of the IMPELA 10/50 is scheduled for early 1989. (orig.)

  20. User Support of Electron Irradiation Facility

    International Nuclear Information System (INIS)

    Park, S. H.; Cha, H. K.; Lee, B. C.

    2007-06-01

    The KAERI (Korean Atomic Energy Research Institute) high-power electron beam irradiation facility, operating at the energies between 0.3 MeV and 10 MeV,has provided irradiation services to users in industries, universities, and institutes via 'Project of utilization and cooperation of users of a large research facility' since 2004. A great attraction of many researchers, almost 750 persons so far according to surveys, to e-beam irradiation technology as well as the growth of participants on Workshop on Electron Beam Applications from 121 to 176 indicate the increase of demands of irradiation service. Comparing to the cases of advanced nations in this area, such as America, Japan, China, and Russia, Korea is relatively much behind in radiation technology. It is mainly due to the lack of governmental supports and investments. Active support and investment on construction and operation of electron beam user facilities would be principal factors on developments of advanced technologies. In this project, we would like to satisfy users' requests by developing the effective managing and operating system for prompt services, processes, and QA and to ultimately assist users to create additional new results, by maximizing the utilization of all available resources and activating the developments of technologies of electron beam processing

  1. Effect of gamma rays doses on pollen germination, polysiphony and pollen tube elongation in Pinus patula Schiede et Deppe

    International Nuclear Information System (INIS)

    Katiyar, S.R.; Chauhan, Y.S.

    1987-01-01

    The present study aimed to study the effects of gamma radiation ( 60 Co) on pollen germination and pollen tube elongation in Pinus patula. Pollen germination and pollen tube elongation are stimulated by low doses of radiation. Although higher doses of radiation inhibit the germination of pollen, pollen tube elongation remains unaffected. Thus in Pinus patula pollen tube elongation is less radiosensitive than pollen germination. Compared to control pollen, irradiated pollen produced more number of long pollen tubes. Therefore pollen tube size can be improved using low doses of radiation. (author). 15 refs., 5 figs., 2 tables

  2. Thermal conductivity of electron-irradiated graphene

    Science.gov (United States)

    Weerasinghe, Asanka; Ramasubramaniam, Ashwin; Maroudas, Dimitrios

    2017-10-01

    We report results of a systematic analysis of thermal transport in electron-irradiated, including irradiation-induced amorphous, graphene sheets based on nonequilibrium molecular-dynamics simulations. We focus on the dependence of the thermal conductivity, k, of the irradiated graphene sheets on the inserted irradiation defect density, c, as well as the extent of defect passivation with hydrogen atoms. While the thermal conductivity of irradiated graphene decreases precipitously from that of pristine graphene, k0, upon introducing a low vacancy concentration, c reduction of the thermal conductivity with the increasing vacancy concentration exhibits a weaker dependence on c until the amorphization threshold. Beyond the onset of amorphization, the dependence of thermal conductivity on the vacancy concentration becomes significantly weaker, and k practically reaches a plateau value. Throughout the range of c and at all hydrogenation levels examined, the correlation k = k0(1 + αc)-1 gives an excellent description of the simulation results. The value of the coefficient α captures the overall strength of the numerous phonon scattering centers in the irradiated graphene sheets, which include monovacancies, vacancy clusters, carbon ring reconstructions, disorder, and a rough nonplanar sheet morphology. Hydrogen passivation increases the value of α, but the effect becomes very minor beyond the amorphization threshold.

  3. Polymeric materials obtained by electron beam irradiation

    International Nuclear Information System (INIS)

    Dragusin, M.; Moraru, R.; Martin, D.; Radoiu, M.; Marghitu, S.; Oproiu, C.

    1995-01-01

    Research activities in the field of electron beam irradiation of monomer aqueous solution to produce polymeric materials used for waste waters treatment, agriculture and medicine are presented. The technologies and special features of these polymeric materials are also described. The influence of the chemical composition of the solution to ba irradiated, absorbed dose level and absorbed dose rate level are discussed. Two kinds of polyelectrolytes, PA and PV types and three kinds of hydrogels, pAAm, pAAmNa and pNaAc types, the production of which was first developed with IETI-10000 Co-60 source and then adapted to the linacs built in Accelerator Laboratory, are described. (author)

  4. Obtaining apple haploid plants (Malus X domestica Borkh.) from in situ parthenogenesis induced by irradiated pollen and in vitro culture of immature seeds

    International Nuclear Information System (INIS)

    Zhang, Y.X.; Lespinasse, Y.; Chevreau, E.

    1988-01-01

    Two apple varieties, ''Erovan'' and ''Lodi'', have been pollinated with pollen carrying the marker gene R irradiated by gamma rays from Cobalt 60 with doses of 500, 1000 and 1500 Gy. By in vitro cultures of the immature seeds removed 7 to 13 weeks after pollination, haploid plants (2n=x=17) have been obtained from ''Erovan'' [fr

  5. Positron lifetime studies of electron irradiated copper

    International Nuclear Information System (INIS)

    Hadnagy, T.D.

    1976-01-01

    Single-crystal copper was irradiated with 4.5-MeV electrons producing simple Frenkel defects as well as a significant concentration of divacancies. Mean positron lifetime characteristics, which are sensitive to the presence of vacancies and multivacancies in copper, was monitored after isochronal anneals between 80 and 800 0 K to determine the relative change of characteristic mean lifetimes and their associated intensities. Also a study of the dependence of the mean positron lifetime on the total electron fluence was made and compared with existing theories relating these lifetimes to vacancy or multivacancy concentrations. Numerical data from curve fitting procedures using a conventional trapping model for defect-induced changes in positron lifetimes indicate that upon irradiation with 4.5-MeV electrons at 80 0 K, about 8 percent of the defects produced are divacancy units. Divacancy units appear to be several times more effective in trapping positrons than are monovacancies. Further, the experimental data suggest that the stage III annealing processes in electron-irradiated copper most probably involve the motion and removal of both monovacancies and divacancies. A conglomerate (multivacancy) unit appears to exist as a stable entity even after annealing procedures are carried out at temperatures slightly above the stage III region. Such a stable unit could serve as a nucleation center for the appearance of voids

  6. Stress relaxation under cyclic electron irradiation

    International Nuclear Information System (INIS)

    Bystrov, L.N.; Reznitskij, M.E.

    1990-01-01

    The kinetics of deformation process in a relaxating sample under 2 MeV electron cyclic irradiation was studied experimentally. The Al-Mg alloys with controllable and different (in dislocation density precipitate presence and their character) structure were used in experiments. It was established that after the beam was switched on the deformation rate increased sharply and then, during prolonged irradiation, in a gradual manner. After the switching-off the relaxation rate decreases by jumps up to values close to extrapolated rates of pre-radiation relaxation. The exhibition of these effects with radiation switching-off and switchin-on is dependent on the initial rate of thermal relaxation, the test temperature, the preliminary cold deformation and the dominating deformation dislocation mechanism. The preliminary cold deformation and test temperature elevation slightly decrease the effect of instantaneous relaxation acceleration with the irradiation switch-on. 17 refs., 5 figs

  7. Spectrum of allergenic pollen in Karachi and their characterization using conventional and electron microscopy: Potential candidates for allergy vaccines

    International Nuclear Information System (INIS)

    Parveen, A.; Noori, M.Y.; Qureshi, M.A.

    2015-01-01

    Objective: To study the distribution of naturally growing plants with possible allergenic potential and study their pollen morphology in Karachi, Pakistan. Methodology: We performed field surveys of naturally growing plants with possible allergenic potential and studied their pollen morphology using conventional (light) as well as scanning electron microscopy. Results: About 80 allergenic pollen producing species were identified which are distributed in 45 genera and 9 angiospermic families. Grasses belonging to Graminae are most abundant followed by plants from family Fabaceae (Leguminosae). Highly allergenic weeds were also found widely growing in the city areas belonging to Amaranthaceae/Chenopodiaceae family. Conclusion: Our study provides an updated information about the allergenic plants growing in Karachi city. All desensitization efforts should be designed in accordance to the available information regarding the prevalent allergens in the environment so that appropriate therapy can be given to the affected population. (author)

  8. Exhaust gas treatment by electron beam irradiation

    International Nuclear Information System (INIS)

    Shibamura, Yokichi; Suda, Shoichi; Kobayashi, Toshiki

    1991-01-01

    Among global environmental problems, atmospheric pollution has been discussed since relatively old days, and various countermeasures have been taken, but recently in connection with acid rain, the efficient and economical treatment technology is demanded. As the denitration and desulfurization technology for the exhaust gas from the combustion of fossil fuel, the incineration of city trash and internal combustion engines, three is the treatment method by electron beam irradiation. By irradiating electron beam to exhaust gas, nitrogen oxides and sulfur oxides are oxidized to nitric acid and sulfuric acid, and by promoting the neutralization of these acids with injected alkali, harmless salts are recovered. This method has the merit that nitrogen oxides and surfur oxides can be removed efficiently with a single system. In this report, as for the exhaust gas treatment by electron beam irradiation, its principle, features, and the present status of research and development are described, and in particular, the research on the recent exhaust gas treatment in city trash incineration is introduced. This treatment method is a dry process, accordingly, waste water disposal is unnecessary. The reaction products are utilized as fertilizer, and waste is not produced. (K.I.)

  9. Electron irradiation effects on lithium peroxide

    Science.gov (United States)

    Kikkawa, Jun; Shiotsuki, Taishi; Shimo, Yusuke; Koshiya, Shogo; Nagai, Takuro; Nito, Takehiro; Kimoto, Koji

    2018-03-01

    In this study, electron irradiation effects on lithium peroxide (Li2O2), which is an important discharge product of Li-air (or Li-O2) batteries, were investigated using selected-area electron diffraction (SAED) and high-energy resolution electron energy-loss spectroscopy (EELS). The results obtained show that Li2O2 to Li2O transformation occurs with 80 and 300 keV incident electrons under high electron dose rates at 20 and -183 °C. The Li2O2 to Li2O transformation rate for 300 keV was 1/5 of that for 80 keV with the irradiation taking place at -183 °C. We also present a series of the EELS spectra that can be used as a criterion to judge the molar ratio of Li2O to Li2O2 in the general systems where Li2O2 and Li2O coexist.

  10. Use of electron accelerators in food irradiation

    International Nuclear Information System (INIS)

    Sanyal, Bhaskar

    2013-01-01

    Preservation of food by ionizing radiations involves controlled application of energy of radiation to agricultural commodities, foods and food ingredients, for improving storage life, hygiene and safety. Insects and microbes cause major economic losses to stored crops. Many of our food products are contaminated with diseases causing germs and toxin producing molds. Without improvement in microbial quality and getting properly treated to overcome quarantine barriers our agricultural products cannot get international markets. In this respect electron accelerators have immense potential in commercial radiation processing of foods. Both low and high dose applications with increased process rates can be achieved using accelerators to cover a wide spectrum of food commodities approved for commercial radiation processing as per the recent gazette notification under Atomic Energy (Radiation Processing of Food and Allied Products) Rule, 2012. The effectiveness of processing of food by ionizing radiation depends on proper delivery of absorbed dose and its reliable measurement. For food destined for international trade, it is important that the dosimetry used for dose determination is carried out accurately and that the process is monitored in accordance with the internationally accepted procedures. Experiments using alanine-EPR system were carried out to optimize the process parameters of 10 MeV electron beam for commercial irradiation of food. Different food commodities namely, mango, potato and rawa (semolina) were irradiated to measure the absorbed dose distribution. The actual depth dose profile in food products and useful scan width of the electron beam were determined for commercial radiation processing of food using electron beam. (author)

  11. Determination of the electron beam irradiated area

    International Nuclear Information System (INIS)

    Zarbout, K.; Kallel, A.; Moya, G.

    2005-01-01

    The investigation of the charge trapping properties of non-conductive materials open the way to an understanding of the degradation of their characteristics due to ageing and catastrophic phenomena, such as breakdown, which originate from the rapid relaxation of trapped charges. The defects, in particular those introduced during the fabrication process, are responsible for the charging phenomena which limit the technological performances and the reliability of these materials. Several characterisation techniques have been developed and among them the one which uses the electron beam of the scanning Electron Microscope (SEM). The study of the charge trapping properties in non-conductive solids by using the electron beam of a SEM requires the knowledge of the current beam and injected charges densities. These densities depend on the irradiated sample area. For this reason, we report in this work two experimental procedures allowing a direct determination of the irradiated area size by the incident defocused beam. The first is based on the charging effect of oxide surfaces (SiO2, MgO, AL2O3) and the second is derived from the electron beam lithography technique. The latter procedure constitutes a convenient experimental method

  12. Commercializing ALURTRONs electron beam irradiation services

    International Nuclear Information System (INIS)

    Siti Aiasah Hashim; Mohd Sidek Othman; Shari Jahar; Sarada Idris; Naurah Mohd Isa; Muhamad Zahidee Taat

    2010-01-01

    ALURTRON has been the nation's sole electron irradiation service provider for research sectors. The main irradiation is done by utilising the EPS 3000 Cockcroft-Walton type 3.0 MeV, 90 k Watts electron beam machine (EBM). With more than 15 years experience in the operation and maintenance of the EPS, the challenge is now to commercialize the service at a larger and profitable scale. Medical products sterilization at commercial level has been ruled out since the energy is insufficient to penetrate dense and non-homogenous items. Recently, the demand for irradiation of wire and heat shrinkable tubes is showing bigger commercial potential. Therefore, prudent planning considerations need to be taken to ensure profitable return to the agency. Calculations were made to estimate ALURTRON service capacity, based on the existing EBM and its auxiliary systems. Details of the calculation including all the variables are presented. Results indicated that Alurtron should be able to process a minimum of 1000 km of small wires per month, running at 150 m/ min, working in two shifts, 5 days a week. The projected revenue is dependent on the charges imposed on the basis of total length delivered. (author)

  13. Use of the Ethanolic Extract of Bee Pollen (Bee Bread) and Gamma Irradiation for Keeping the Quality of Silver Carp (Hypophthalmichthys Molitrix) Fish Patties

    International Nuclear Information System (INIS)

    Gibriel, AY.; Abdeldaiem, M.H.; Ali, H.G.M.

    2016-01-01

    This investigation was carried out to extend the shelf-life of silver carp fish patties (Hypophthalmichthys molitrix) by the use of ethanolic extract of bee pollen (bee bread) at concentration of 4%, and gamma irradiation at doses of 1, 3 and 5 kGy as an individual treatment. The first group was control, the second group was silver carp fish patties samples treated with 4 % the ethanolic extract of bee pollen (bee bread) then irritated at doses of 1, 3 and 5 kGy. The effects of these treatments on the microbiological, chemical and sensory characteristics of silver carp fish patties samples have been observed. In addition, shelf-life periods were higher for silver carp fish patties samples treated by 4% the ethanolic extract of bee pollen (bee bread) and gamma radiation at dose of 5 kGy. This treatment was more effective as antimicrobial, consequently may be useful as natural food preservative.

  14. WEBEXPIR: Windowless target electron beam experimental irradiation

    International Nuclear Information System (INIS)

    Dierckx, Marc; Schuurmans, Paul; Heyse, Jan; Rosseel, Kris; Tichelen, Katrien Van; Nactergal, Benoit; Vandeplassche, Dirk; Aoust, Thierry; Abs, Michel; Guertin, Arnaud; Buhour, Jean-Michel; Cadiou, Arnaud; Abderrahim, Hamid Ait

    2008-01-01

    The windowless target electron beam experimental irradiation (WEBEXPIR) program was set-up as part of the MYRRHA/XT-ADS R and D effort on the spallation target design to investigate the interaction of a proton beam with a liquid lead-bismuth eutectic (LBE) free surface. In particular, possible free surface distortion or shockwave effects in nominal conditions and during sudden beam on/off transient situations, as well as possible enhanced evaporation were assessed. An experiment was conceived at the IBA TT-1000 Rhodotron, where a 7 MeV electron beam was used to simulate the high power deposition at the MYRRHA/XT-ADS LBE free surface. The geometry and the LBE flow characteristics in the WEBEXPIR set-up were made as representative as possible of the actual situation in the MYRRHA/XT-ADS spallation target. Irradiation experiments were carried out at beam currents of up to 10 mA, corresponding to 40 times the nominal beam current necessary to reproduce the MYRRHA/XT-ADS conditions. Preliminary analyses show that the WEBEXPIR free surface flow was not disturbed by the interaction with the electron beam and that vacuum conditions stayed well within the design specifications

  15. 'Hertwig effect' in plants: Induced parthenogenesis through the use of irradiated pollen

    International Nuclear Information System (INIS)

    Pandey, K.K.; Phung, M.

    1982-01-01

    Studies of four combinations of Nicotiana involving four species, N. langsdorffii (N.l.), N. alata (N.a.), N. glutinosa (N.g.) and N. tubacum (N.t.), have shown that parthenogenetic haploid and diploid maternal individuals may arise with the use of male gametes (pollen) treated with high doses of ionising radiation in plants, similar to that found in animals ('Hertwig Effect'). At lower doses (10-20 Kr) rapidly diminishing numbers of seedlings were produced and many of these died soon after germination or before reaching maturity. In the intraspecific combination N.l.xN.l., viable seeds were produced only at the lower doses of 10 and 15 Kr. In the interspecific combination N.l.xN.a., at lower doses, all plants that came to bloom showed variable hybrid morphology. There were no plants resembling the female parent. (orig./AJ)

  16. Electron beam irradiation of fluoropolymers containing polyethers

    Science.gov (United States)

    Bucio, E.; Burillo, G.; Tapia, F.; Adem, E.; Cedillo, G.; Cassidy, P. E.

    2009-02-01

    A highly fluorinated monomer, 1,3-bis(1,1,1,3,3,3-hexafluoro-2-pentafluorophenyl methoxy-2-propyl)benzene (12F-FBE) was polymerized with some diphenols by polycondensation and then was electron beam irradiated between 100 and 1000 kGy to determine degradation radiochemistry yield ( Gs) by gel permeation chromatography (GPC). The samples were characterized after irradiation by DSC, FTIR, and nuclear magnetic resonance (NMR). The fluoropolymers show apparent degradation in mechanical properties at 300 kGy, except 12F-FBE polymerized with biphenol and bisphenol A, when they did not show any apparent physical change up to 300 kGy; and continue to be flexible and transparent, with a radiochemical yield scission ( Gs) of 0.75, 0.53, 0.88, and 0.38 for 12F-FBE/SDL aliphatic, 12F-FBE/biphenol, 12F-FBE/bisphenol A, and 12F-FBE/bisphenol O, respectively. The number average molecular weights for three of the polymers decrease upon 1000 kGy irradiation to 10% of their original values; however, the polymer from bisphenol A is much more stable and its Mn decreases to only 24% of original.

  17. Electron beam irradiation of fluoropolymers containing polyethers

    International Nuclear Information System (INIS)

    Bucio, E.; Burillo, G.; Tapia, F.; Adem, E.; Cedillo, G.; Cassidy, P.E.

    2009-01-01

    A highly fluorinated monomer, 1,3-bis(1,1,1,3,3,3-hexafluoro-2-pentafluorophenyl methoxy-2-propyl)benzene (12F-FBE) was polymerized with some diphenols by polycondensation and then was electron beam irradiated between 100 and 1000 kGy to determine degradation radiochemistry yield (G s ) by gel permeation chromatography (GPC). The samples were characterized after irradiation by DSC, FTIR, and nuclear magnetic resonance (NMR). The fluoropolymers show apparent degradation in mechanical properties at 300 kGy, except 12F-FBE polymerized with biphenol and bisphenol A, when they did not show any apparent physical change up to 300 kGy; and continue to be flexible and transparent, with a radiochemical yield scission (G s ) of 0.75, 0.53, 0.88, and 0.38 for 12F-FBE/SDL aliphatic, 12F-FBE/biphenol, 12F-FBE/bisphenol A, and 12F-FBE/bisphenol O, respectively. The number average molecular weights for three of the polymers decrease upon 1000 kGy irradiation to 10% of their original values; however, the polymer from bisphenol A is much more stable and its M n decreases to only 24% of original

  18. FTIR spectroscopy of electron irradiated polymers

    International Nuclear Information System (INIS)

    Finch, D.S.

    1988-04-01

    The chemical changes in electron beam irradiated polymers, in particular PVC, are considered in order to relate the formation of conjugated structures to changes in the electrical properties. Infrared spectroscopy has been used to measure these changes. Fourier Transform techniques and computing facilities make better data processing possible. A method for base line interpretation is demonstrated whereby a shift parallel to the abscisal axis in a region of the polymer that is non absorbing is used to evaluate the baseline. This technique has proved to be highly reproducible providing that the polymer films to be examined are optically homogeneous. Evaluation of the rate of decay of the total area of the carbon chlorine region of the polymer has been compared with the chlorine decay curve analysed by the measurement of x-ray emission during irradiation of bulk samples. The significant reduction in the evolution of atomic chlorine through x-ray analysis has been attributed to the trapping of HCl within the polymer film and its subsequent slow diffusion out of the polymer. With PVC, one of the main products as a result of irradiation is the formation of conjugated sequences. These were studied by the use of uv-visible spectroscopy. (author)

  19. Windowless Electron Beam Experimental Irradiation WEBExplr

    International Nuclear Information System (INIS)

    Heyse, J.

    2009-01-01

    The design of the MYRRHA/XT-ADS, the European eXperimental Accelerator Driven System for the demonstration of Transmutation, includes a high power windowless spallation target operating with liquid LBE (Lead-Bismuth Eutectic) that will be irradiated with a 600 MeV proton beam at currents of up to 2.5 mA. When considering such a high power windowless target design, a number of questions need to be addressed, such as the stability of the free surface flow and its ability to remove the power deposited by the proton beam by forced convection, the compatibility of a large hot LBE reservoir with the beam line vacuum and the outgassing of the LBE in the spallation target circuit. These issues have been studied during previous experiments supported by numerical simulations. Another crucial point in the development of the spallation target is the demonstration of the safe and stable operation of the free LBE surface during irradiation with a high power proton beam. As a first step in this program, the WEBExpIr (Windowless target Electron Beam Experimental Irradiation) experiment was set up. The purpose of the WEBExpIr experiment was to investigate the influence of LBE surface heating caused by a charged particle beam in a situation representative of the MYRRHA/XT-ADS. More in particular, we wanted to assess possible free surface distortion or shockwave effects in nominal conditions and during sudden beam on/off transient situations, as well as possible enhanced evaporation

  20. Pollen DNA repair after treatment with the mutagens 4-nitroquinoline-1-oxide, ultraviolet and near-ultraviolet irradiation, and boron dependence of repair

    International Nuclear Information System (INIS)

    Jackson, J.F.; Linskens, H.F.; Katholieke Universiteit Nijmegen

    1979-01-01

    Irradiation of dry, mature pollen from Petuna hybrida with near-ultraviolet light from an erythemal-sunlamp gave rise to a repair-like, unscheduled DNA synthesis during the early stages of in vitro germination. Like that brought about by far-ultraviolet light from a germicidal lamp, this DNA synthesis is enhanced by hydroxyurea added to the germination medium, and reduced by photoreactivating light given after ultraviolet irradiation and before germination begins. It is concluded that pollen, often receiving considerable exposure to sunlight, has, in addition to the protection afforded by the ultraviolet filtering effects of yellow pigments, also the capacity to repair ultraviolet produced changes in DNA, by both photoreactivation and dark repair processes. (orig./AJ) [de

  1. Application of electron beam irradiation. 4. Treatment of pollutants by electron beam irradiation

    International Nuclear Information System (INIS)

    Tokunaga, Okihiro; Arai, Hidehiko

    1994-01-01

    Electron beam irradiation is capable of dissolving and removing pollutants, such as sulfur oxides, nitrogen oxides, and organic compounds, by easy production of OH radicals in flue gas and water. This paper deals with current status in the search for techniques for treating flue gas and waste water, using electron beam irradiation. Pilot tests have been conducted during the period 1991-1994 for the treatment of flue gas caused by coal and garbage burning and road tunnels. Firstly, techniques for cleaning flue gas with electron beams are outlined, with special reference to their characteristics and process of research development. Secondly, the application of electron beam irradiation in the treatment of waste water is described in terms of the following: (1) disinfection of sewage, (2) cleaning of water polluted with toxic organic compounds, (3) treatment for eliminating sewage sludge, (4) promotion of sewage sludge sedimentation, (5) disinfection and composting of sewage sludge, and (6) regeneration of activated carbon used for the treatment of waste water. (N.K.)

  2. The electron irradiation effects in different structures of diodes

    International Nuclear Information System (INIS)

    Li Quanfen; Wang Jiaxu

    1993-01-01

    This paper describes the different electron irradiation effects in different structures of diodes and the different results produced by different irradiation ways. From this work, we can know how to choose proper manufacture arts and comprehensive factors according to the structures of diodes and the irradiation conditions

  3. Sprout inhibition of potatoes by electron irradiation, (2)

    International Nuclear Information System (INIS)

    Furuta, Junichiro; Hiraoka, Eiichi; Okamoto, Shinichi; Fujishiro, Masatoshi; Kanazawa, Tamotsu; Ohnishi, Tokuhiro; Tsujii, Yukio; Hori, Shiro

    1982-01-01

    Sprouting of potatoes are inhibited usually by the gamma-ray irradiation. The buds of potatoes exist in a very thin layer near surface of each tuber. So the inhibition will be performed sufficiently by surface irradiation using electron beams. To irradiate all surfaces of each potato uniformly, the authors prepare a new apparatus which is a conveyer passing under an electron beam scanner of accelerator rotating the potatoes by many rotating rollers. The sprout inhibition experiment of potatoes was performed by following three methods to obtain the performance of this apparatus, and the results were compared. 1) turn over irradiation method --- potatoes were arranged in one layer in plastic baskets and were irradiated on the conveyor. After irradiation, the potatoes were turned over and were irradiated again. 2) rotating irradiation method --- potatoes were rotated on the rotating roller apparatus set on the conveyer and were passed under the electron beam scanner. 3) rotating irradiation method with an improved rotating roller apparatus --- the rotating rollers have many protuberances on their surface to irradiate all of potato surface more uniform. 550 keV electron beams by Cockcroft-Walton type accelerator were used for the irradiation and the irradiated dose was 5 to 20 krad. 40 pieces of potates, ''Danshaku'' variety yielded in June 1981, were irradiated for each dose in the beginning of August. Prior to these irradiation experiments, the dose and dose uniformity were checked by the agar color dosimeters. After the irradiation, potatoes were stored in natural condition and their sprouting was observed. The potatoes irradiated by the improved rotating roller apparatus were almost completely sprout-inhibited by 20 krad irradiation. (author)

  4. Design of electron detection system for pulse electron irradiator

    International Nuclear Information System (INIS)

    Anjar Anggraini H; Agus Purwadi; Lely Susita RM; Bambang Siswanto; Agus Wijayanto

    2016-01-01

    Design of electron detection system for pulse electron irradiator has been conducted on the Plasma Cathode Electron Source by Rogowski coil technique. Rogowski coil has ability to capture the induced magnetic field of the electric current, subsequent induced magnetic field will provide voltage after passing integrator. This diagnostic used combination of copper wire, ferrite and RC integrator. The design depends on the pulse width and the value of plasma current that passes through the coil, thus the number of windings, coil area and integrator can be designed. For plasma spots current of IDPS expected to be 10 A and pulse width 10 μs the Rogowski coil using MnZn ferrite with inductance L = 0.275 mH and permeability μr = 200 H/m. For the current of plasma arc ADPS expected to be 100 A and pulse width 100 μs by using inductance L=1.9634 mH and permeability μr = 6256 H/m. Electron current in extraction system expected to be 30 A and pulse width 100 μs the Rogowski coil using inductance L=51.749 mH and permeability μr= 4987 H/m. Design integrator used is the type of RC integrator. (author)

  5. Simulation model for electron irradiated IGZO thin film transistors

    Science.gov (United States)

    Dayananda, G. K.; Shantharama Rai, C.; Jayarama, A.; Kim, Hyun Jae

    2018-02-01

    An efficient drain current simulation model for the electron irradiation effect on the electrical parameters of amorphous In-Ga-Zn-O (IGZO) thin-film transistors is developed. The model is developed based on the specifications such as gate capacitance, channel length, channel width, flat band voltage etc. Electrical parameters of un-irradiated IGZO samples were simulated and compared with the experimental parameters and 1 kGy electron irradiated parameters. The effect of electron irradiation on the IGZO sample was analysed by developing a mathematical model.

  6. Coating composition curable by electron beam irradiation

    International Nuclear Information System (INIS)

    Masuda, Hiromasa; Iijima, Ken-ichi.

    1971-01-01

    Here is provided a coating composition curable with low dose of electron beams to give a smooth coating film having no surface tackiness. In one example, 126 parts of melamine was reacted with 682 parts of formalin followed by 697 parts of β-hydroxyethyl acrylate to produce component (A) (viscosity 780 cp). On the other hand, 900 parts of tung oil was reacted with 343 parts of maleic anhydride followed by 22 parts of dimethylaminoethyl methacrylate and 406 parts of β-hydroxyethyl acrylate. The resulting product was diluted with 508 parts of methyl methacrylate to give component (B) (dark red, viscous substance). 900 parts of (A), 100 parts of (B), 0.5 part of bees wax and 0.2 part of paraffin wax were blended together. A sized material was coated with the mixture and irradiated with electron beams (6 Mrad) in the presence of air. A smooth film free from surface tackiness was obtained. β-hydroxyethyl acrylate may be replaced by other hydroxyalkyl esters of α,β-unsaturated acids, and melamine may be replaced by urea, benzoguanamine or acetoguanamine. Tung oil may be replaced by linseed, safflower, soybean, rice, oiticica or cotton seed oil. A more flexible film is obtained by using component (B) in a larger proportion. (A)/(B) ratio should be in the range of 90/10 to 10/90 by wt. (Kaichi, S.)

  7. Electron trapping during irradiation in reoxidized nitrided oxide

    International Nuclear Information System (INIS)

    Mallik, A.; Vasi, J.; Chandorkar, A.N.

    1993-01-01

    Isochronal detrapping experiments have been performed following irradiation under different gate biases in reoxidized nitrided oxide (RNO) MOS capacitors. These show electron trapping by the nitridation-induced electron traps at low oxide fields during irradiation. A difference in the detrapping behavior of trapped holes and electrons is observed, with trapped holes being detrapped at relatively lower temperatures compared to trapped electrons. Electron trapping shows a strong dependence on tile magnitude of the applied gate bias during irradiation but is independent of its polarity. Conventional oxide devices, as expected, do not show any electron trapping during irradiation by the native electron traps. Finally, a comparison of the isochronal detrapping behavior following irradiation and following avalanche injection of electrons has been made to estimate the extent of electron trapping. The results show that electron trapping by the nitridation-induced electron traps does not play the dominant role in improving radiation performance of RNO, though its contribution cannot be completely neglected for low oxide field irradiations

  8. Comparison of electron-irradiation and gamma-irradiation as a decontamination treatment of spices

    International Nuclear Information System (INIS)

    Hayashi, Toru; Todoriki, Setsuko; Mamun.

    1993-01-01

    Electron-irradiation at 10 kGy decontaminated all the eight kinds of spices (black pepper, white pepper, nutmeg, red pepper, parsley, paprika, laurel and onion powder) to the microbial levels lower than 10 2 /g. Similar sterilization effects by the irradiation were observed on heat-resistant bacterial spores. The 10 kGy irradiation did not significantly affect the contents of essential oils and colors of the spices. These results indicate that electron-irradiation at 10 kGy effectively decontaminates spices without notable adverse effect on the qualities. The disinfecting effect of electron beams on spices was smaller than that of gamma-rays. (author)

  9. Effect of electron beam irradiation on seed germination

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seunghee; Bae, Youngmin [Changwon Univ., Changwon (Korea, Republic of)

    2013-07-01

    Effect of electron beam irradiation on seed germination was investigated in this research. Electron beam of 0.5, 1.0, 1.5 and 2.0 kGy was irradiated to the seeds of lettuce, green onion and cucumber, and the irradiated seeds were incubated at 25 .deg. Cn Nitsch medium solidified with 0.2% Phytagel. Germination percentage and the length of the sprouts were determined after 72 hours. Germination percentage of lettuce seeds was greatly reduced by the irradiation, and that of the green onion and cucumber were moderately reduced or unchanged by the irradiation. Although average length of the lettuce sprouts was reduced severely, that of the green onion and cucumber was unchanged or moderately reduced. Conclusively, electron beam irradiation might be a useful way of disinfecting some plant seeds including green onion and cucumber.

  10. Effect of electron beam irradiation on seed germination

    International Nuclear Information System (INIS)

    Han, Seunghee; Bae, Youngmin

    2013-01-01

    Effect of electron beam irradiation on seed germination was investigated in this research. Electron beam of 0.5, 1.0, 1.5 and 2.0 kGy was irradiated to the seeds of lettuce, green onion and cucumber, and the irradiated seeds were incubated at 25 .deg. Cn Nitsch medium solidified with 0.2% Phytagel. Germination percentage and the length of the sprouts were determined after 72 hours. Germination percentage of lettuce seeds was greatly reduced by the irradiation, and that of the green onion and cucumber were moderately reduced or unchanged by the irradiation. Although average length of the lettuce sprouts was reduced severely, that of the green onion and cucumber was unchanged or moderately reduced. Conclusively, electron beam irradiation might be a useful way of disinfecting some plant seeds including green onion and cucumber

  11. Cost evaluation of irradiation system with electron accelerator

    International Nuclear Information System (INIS)

    Kashiwagi, M.

    2003-01-01

    The features of electron beam irradiation system using electron accelerator are direct energy pour into the irradiated material, no third material mixture such as catalyst, suitable for mass production and easy operation and maintenance work available. These features can bring the various applications such as cross-linking action, graft polymerization, radical polymerization and others. The selection of electron accelerator ratings is made under consideration of quality, width and thickness of irradiated material, production amount, dose required for reaction and irradiation atmosphere. Especially in a case of irradiation of wire with high insulation material such as polyethylene, the consideration of maximum thickness toward irradiation direction is necessary to avoid the discharge (Lichtenberg discharge) by charged-up electrons inside insulation material. Therefore, the acceleration voltage should be selected to make the maximum penetration larger than maximum irradiation thickness. The actual model case of estimate the irradiation cost was selected that the irradiation object was polyethylene insulated wire up to AWG no.14, irradiation amount was 5,000 km/month, necessary dose was 200 kGy, operation time was 22 d/month and 8 h/day and actual operation efficiency was considered loss time such as bobbin changing as 80%. The selected ratings of electron accelerator were acceleration voltage of 800 kV, beam current of 100 mA and irradiation width of 180 cm with irradiation pulleys stand of 60 turns x 3 lanes. The initial total cost was estimated as 3 M$(US) and operation cost was evaluated as 215 k$(US). Therefore, the irradiation cost of wire was evaluated as 0.0036 $/m. (author)

  12. Electron irradiation induced nanocrystal formation in Cu-borosilicate glass

    Energy Technology Data Exchange (ETDEWEB)

    Sabri, Mohammed Mohammed; Möbus, Günter, E-mail: g.moebus@sheffield.ac.uk [University of Sheffield, Department of Materials Science and Engineering (United Kingdom)

    2016-03-15

    Nanoscale writing of Cu nanoparticles in glasses is introduced using focused electron irradiation by transmission electron microscopy. Two types of copper borosilicate glasses, one with high and another with low Cu loading, have been tested at energies of 200–300 keV, and formation of Cu nanoparticles in a variety of shapes and sizes using different irradiation conditions is achieved. Electron energy loss spectroscopy analysis, combined with high-resolution transmission electron microscopy imaging, confirmed the irradiation-induced precipitated nanoparticles as metallic, while furnace annealing of the glass triggered dendrite-shaped particles of copper oxide. Unusual patterns of nanoparticle rings and chains under focused electron beam irradiation are also presented. Conclusively, electron beam patterning of Cu-loaded glasses is a promising alternative route to well-established femtosecond laser photoreduction of Cu ions in glass.

  13. Identification of irradiated chicken meat using electron spin resonance spectroscopy

    International Nuclear Information System (INIS)

    Chawla, S.P.; Thomas, Paul

    2004-01-01

    Studies were carried out on detection of irradiation treatment in chicken using electron spin resonance (ESR) spectroscopy. The effect of gamma- irradiation treatment on radiation induced signal in different types of chicken namely, broiler, deshi and layers was studied. Irradiation treatment induced a characteristic ESR signal that was not detected in non-irradiated samples. The shape of the signal was not affected by type of the bone. The intensity of radiation induced ESR signal was affected by factors such as absorbed radiation dose, bone type irradiation temperature, post-irradiation storage, post-irradiation cooking and age of the bird. Deep-frying resulted in the formation of a symmetric signal that had a different shape and was weaker than the radiation induced signal. This technique can be effectively used to detect irradiation treatment in bone-in chicken meat even if stored and/or subjected to various traditional cooking procedures. (author)

  14. Dose controlled low energy electron irradiator for biomolecular films.

    Science.gov (United States)

    Kumar, S V K; Tare, Satej T; Upalekar, Yogesh V; Tsering, Thupten

    2016-03-01

    We have developed a multi target, Low Energy Electron (LEE), precise dose controlled irradiator for biomolecular films. Up to seven samples can be irradiated one after another at any preset electron energy and dose under UHV conditions without venting the chamber. In addition, one more sample goes through all the steps except irradiation, which can be used as control for comparison with the irradiated samples. All the samples are protected against stray electron irradiation by biasing them at -20 V during the entire period, except during irradiation. Ethernet based communication electronics hardware, LEE beam control electronics and computer interface were developed in house. The user Graphical User Interface to control the irradiation and dose measurement was developed using National Instruments Lab Windows CVI. The working and reliability of the dose controlled irradiator has been fully tested over the electron energy range of 0.5 to 500 eV by studying LEE induced single strand breaks to ΦX174 RF1 dsDNA.

  15. Dose controlled low energy electron irradiator for biomolecular films

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S. V. K., E-mail: svkk@tifr.res.in; Tare, Satej T.; Upalekar, Yogesh V.; Tsering, Thupten [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005 (India)

    2016-03-15

    We have developed a multi target, Low Energy Electron (LEE), precise dose controlled irradiator for biomolecular films. Up to seven samples can be irradiated one after another at any preset electron energy and dose under UHV conditions without venting the chamber. In addition, one more sample goes through all the steps except irradiation, which can be used as control for comparison with the irradiated samples. All the samples are protected against stray electron irradiation by biasing them at −20 V during the entire period, except during irradiation. Ethernet based communication electronics hardware, LEE beam control electronics and computer interface were developed in house. The user Graphical User Interface to control the irradiation and dose measurement was developed using National Instruments Lab Windows CVI. The working and reliability of the dose controlled irradiator has been fully tested over the electron energy range of 0.5 to 500 eV by studying LEE induced single strand breaks to ΦX174 RF1 dsDNA.

  16. ESR investigataions of electron-beam irradiated cellulose nitrate

    International Nuclear Information System (INIS)

    Chipara, M.I.; Catana, D.; Grecu, V.; Romero, J.R.; Chipara, D.

    1994-01-01

    Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311) are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and its is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author)

  17. ESR investigataions of electron-beam irradiated cellulose nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Chipara, M.I.; Catana, D. [Institute of Atomic Physics, Bucharest (Romania); Grecu, V.; Romero, J.R. [Bucharest Univ. (Romania). Faculty of Physics; Coca, S. [Chemical Research Inst., Bucharest (Romania); Chipara, D. [Research Inst. for Electrotechnics, Bucharest (Romania)

    1994-10-01

    Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311) are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and its is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author).

  18. ESR investigations of electron-beam irradiated cellulose nitrate

    International Nuclear Information System (INIS)

    Chipara, M.I.; Grecu, V.; Catana, D.; Romero, J.R.; Coca, S.; Chipara, M.D.

    1994-01-01

    Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311), are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and it is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author)

  19. Electron beam influence on the carbon contamination of electron irradiated hydroxyapatite thin films

    International Nuclear Information System (INIS)

    Hristu, Radu; Stanciu, Stefan G.; Tranca, Denis E.; Stanciu, George A.

    2015-01-01

    Highlights: • Carbon contamination mechanisms of electron-beam-irradiated hydroxyapatite. • Atomic force microscopy phase imaging used to detect carbon contamination. • Carbon contamination dependence on electron energy, irradiation time, beam current. • Simulation of backscattered electrons confirms the experimental results. - Abstract: Electron beam irradiation which is considered a reliable method for tailoring the surface charge of hydroxyapatite is hindered by carbon contamination. Separating the effects of the carbon contamination from those of irradiation-induced trapped charge is important for a wide range of biological applications. In this work we focus on the understanding of the electron-beam-induced carbon contamination with special emphasis on the influence of the electron irradiation parameters on this phenomenon. Phase imaging in atomic force microscopy is used to evaluate the influence of electron energy, beam current and irradiation time on the shape and size of the resulted contamination patterns. Different processes involved in the carbon contamination of hydroxyapatite are discussed

  20. Precipitation in Ni-Si during electron and ion irradiation

    Science.gov (United States)

    Lucas, G. E.; Zama, T.; Ishino, S.

    1986-11-01

    This study was undertaken to further investigate how the nature of the irradiation condition affects precipitation in a dilute Ni-Si system. Transmission electron microscopy (TEM) discs of a solution annealed Ni alloy containing 5 at% Si were irradiated with 400 keV Ar + ions, 200 keV He + ions and 1 MeV electrons at average displacement rates in the range 2 × 10 -5dpa/s to 2 × 10 -3dpa/s at temperatures in the range 25°C to 450°C. Samples irradiated with electrons were observed in situ in an HVEM, while ion irradiated specimens were examined in a TEM after irradiation. Precipitation of Ni 3Si was detected by the appearance of superlattice spots in the electron diffraction patterns. It was found that as the mass of the irradiating species increased, the lower bound temperature at which Ni 3Si precipitation was first observed increased. For electron irradiation, the lower bound temperature at 2 × 10 -3dpa/s was ˜125°C, whereas for 400 keV Ar + irradiation at a similar average displacement rate the lower boundary was approximately 325°C. This suggests that cascade disordering competes with radiation induced solute segregation.

  1. Precipitation in Ni-Si during electron and ion irradiation

    International Nuclear Information System (INIS)

    Lucas, G.E.; Zama, T.; Ishino, S.

    1986-01-01

    This study was undertaken to further investigate how the nature of the irradiation condition affects precipitation in a dilute Ni-Si system. Transmission electron microscopy (TEM) discs of a solution annealed Ni alloy containing 5 at% Si were irradiated with 400 keV Ar + ions, 200 keV He + ions and 1 MeV electrons at average displacement rates in the range 2x10 -5 dpa/s to 2x10 -3 dpa/s at temperatures in the range 25 0 C to 450 0 C. Samples irradiated with electrons were observed in situ in an HVEM, while ion irradiated specimens were examined in a TEM after irradiation. Precipitation of Ni 3 Si was detected by the appearance of superlattice spots in the electron diffraction patterns. It was found that as the mass of the irradiating species increased, the lower bound temperature at which Ni 3 Si precipitation was first observed increased. For electron irradiation, the lower bound temperature at 2x10 -3 dpa/s was ∝125 0 C, whereas for 400 keV Ar + irradiation at a similar average displacement rate the lower boundary was approximately 325 0 C. This suggests that cascade disordering competes with radiation induced solute segregation. (orig.)

  2. Electron irradiation-induced defects in {beta}-SiC

    Energy Technology Data Exchange (ETDEWEB)

    Oshima, Ryuichiro [Osaka Prefectural Univ., Sakai (Japan). Reseach Inst. for Advanced Science and Technology

    1996-04-01

    To add information of point defects in cubic crystal SiC, polycrystal {beta}-SiC on the market was used as sample and irradiated by neutron and electron. In situ observation of neutron and electron irradiation-induced defects in {beta}-SiC were carried out by ultra high-voltage electronic microscope (UHVEM) and ordinary electronic microscope. The obtained results show that the electron irradiation-induced secondary defects are micro defects less than 20 nm at about 1273K, the density of defects is from 2x10{sup 17} to 1x10{sup 18}/cc, the secondary defects may be hole type at high temperature and the preexistant defects control nuclear formation of irradiation-induced defects, effective sink. (S.Y.)

  3. Using electron irradiation to probe iron-based superconductors

    Science.gov (United States)

    Cho, Kyuil; Kończykowski, M.; Teknowijoyo, S.; Tanatar, M. A.; Prozorov, R.

    2018-06-01

    High-energy electron irradiation at low temperatures is an efficient and controlled way to create vacancy–interstitial Frenkel pairs in a crystal lattice, thereby inducing nonmagnetic point-like scattering centers. In combination with London penetration depth and resistivity measurements, the electron irradiation was used as a phase-sensitive probe to study the superconducting order parameter in iron-based superconductors (FeSCs), lending strong support to sign-changing s ± pairing. Here, we review the key results of the effect of electron irradiation in FeSCs.

  4. Changing in tool steels wear resistance under electron irradiation

    International Nuclear Information System (INIS)

    Braginskaya, A.E.; Manin, V.N.; Makedonskij, A.V.; Mel'nikova, N.A.; Pakchanin, L.M.; Petrenko, P.V.

    1983-01-01

    The tool steels and alloys wear resistance under dry friction after electron irradiation has been studied. Electron irradiation of a wide variety of steels is shown to increase wear resistance. In this case phase composition and lattice parameters changes are observed both in matrix and carbides. The conclusion is drawn that an appreciable increase of steel wear resistance under electron irradiation can be explained both by carbide phase volume gain and changes in it's composition and the formation of carbide phase submicroscopic heterogeneities and, possibly, complexes of defects

  5. Effects of electron beam irradiation on cut flowers and mites

    International Nuclear Information System (INIS)

    Dohino, Toshiyuki; Tanabe, Kazuo

    1994-01-01

    Two spotted spider mite, Tetranychus urticae KOCH were irradiated with electron beams (2.5MeV) to develop an alternative quarantine treatment for imported cut flowers. The tolerance of eggs increased with age (1-5-day-old). Immature stages (larva-teleiochrysalis) irradiated at 0.4-0.8kGy increased tolerance with their development. Mated mature females irradiated at 0.4kGy or higher did not produce viable eggs, although temporary recovery was observed at 0.2kGy. Adult males were sterilized at 0.4kGy because non-irradiated virgin females mated with yielded female progeny malformed and sterilized. Various effects of electron beam irradiation were observed when nine species of cut flowers were irradiated in 5MeV Dynamitron accelerator. Chrysanthemum and rose were most sensitive among cut flowers. (author)

  6. Bee Pollen

    Science.gov (United States)

    ... for nutrition; as an appetite stimulant; to improve stamina and athletic performance; and for premature aging, premenstrual ... use bee pollen as a general tonic, to increase urine flow, and for alcohol intoxication. Bee pollen ...

  7. Development of UV absorbing PET through Electron Irradiation

    International Nuclear Information System (INIS)

    Kim, Jung Woo; Lee, Na Eun; Lim, Hyung San; Park, Yang Jeong; Cho, Sung Oh

    2017-01-01

    Experiment to increase UV absorbance through electron beam irradiation on PET was performed. Moreover, surface hardness and roughness of each sample were observed to find the key factor increasing UV absorbance. PET sheets were irradiated with an electron beam at various fluences. The irradiated samples, as well as pristine sample, were subjected to UV-visible spectral study(UV-Vis), pencil hardness test, and scanning electron microscopy(SEM) experiment. In this study, PET samples irradiated at several conditions were analyzed through various measurements. UV absorbance-another meaning of transmittance in this study- of irradiated PET sample increased compared with pristine sample as fluence was increased in UV-Visible spectroscopy experiment.

  8. Effect of electron beam irradiation on fisheries water

    International Nuclear Information System (INIS)

    Sarala Selambakkannu; Khomsaton Abu Bakar; Jamaliah Shariff; Suhairi Alimon

    2012-01-01

    This paper studies about water obtained from fish pond of fisheries research centre. Usual water quality parameters such as pH, COD, Turbidity and Ammonia content were analyzed before and after irradiation. Electron beam irradiation was used to irradiate the water with the dose 100 kGy, 200 kGy and 300 kGy. Only high dose was applied on this water as only a limited amount of samples was supplied. All the parameters indicated a slight increase after irradiation except for the ammonia content, which showed a gradual decrease as irradiation dose increases. Sample condition was changed before irradiation in order to obtain more effective results in the following batch. The water sample from fisheries was diluted with distilled water to the ratio of 1:1.This was followed with irradiation at 100 kGy, 200 kGy and 300 kGy. The results still showed an increase in all parameters after irradiation except for ammonia content. For the following irradiation batch, the pH of the sample was adjusted to pH 4 and pH 8 before irradiation. For this sample the irradiation dose selected was only 100 kGy. A higher value of ammonia was observed for the sample with pH 4 after irradiation. Other parameters were almost the same as the first two batches. (author)

  9. Electron beam irradiation on cation exchanger used for strontium recovery

    International Nuclear Information System (INIS)

    Watanabe, Sou; Nakamura, Masahiro; Nomura, Kazunori; Nakajima, Yasuo; Okamoto, Yoshihiro

    2014-01-01

    Titanate is promising material for radioactive Sr recovery from liquid waste generated in the nuclear facilities. "9"0Sr is one of the most important nuclides in order to release the liquid waste into the environment due to its strong beta-ray decay energy. Although the titanate is applied to radioactive Sr decontamination facility, their resistance to irradiations from radioactive elements adsorbed is not widely investigated so far. In this study, durability of a hydrous titanic acid ion exchanger against beta-ray irradiation were evaluated through electron beam irradiation, elution behaviour of Sr after the irradiation and local structural analysis of the titanate. 1.4 MGy irradiation led to 1% of Sr elution, and the elution could be attributed to defects of O in the titanate induced by the irradiation. Chemical state of Ti of the titanate must be stable up to 2.7 MGy irradiation. (author)

  10. Technology of irradiation of liquids by electron beams

    International Nuclear Information System (INIS)

    Tofaute, K.

    1979-01-01

    The methods of pretreatment, the technical details of the irradiating equipment, the applied radiation doses and the general requirements of the effectively working system are described. The extent of reinfection is compared in cases of heat-treated and electron-irradiated mud. The latter method gave significantly better results. (L.E.)

  11. The effect of composition, electron irradiation and quenching on ...

    Indian Academy of Sciences (India)

    The ionic conductivity at room temperature exhibits a characteristic double peak for the composition = 20 and 70. Both electron beam irradiation and quenching at low temperature have resulted in an increase in conductivity by 1–2 orders of magnitude. The enhancement of conductivity upon irradiation and quenching is ...

  12. Regeneration of used activated carbon by electron beam irradiation

    International Nuclear Information System (INIS)

    Arai, H.; Hosono, M.; Zhu, G.; Miyata, T.

    1992-01-01

    The adsorbing power of granular activated carbons which adsorbed sodium laurylsulfate were most effectively recovered by irradiation of high energy electron beams in nitrogen stream, and the carbon was hardly lost by irradiation. The regeneration was induced mainly by microscopic heating of adsorption sites. Regeneration was also confirmed by adsorption endotherms. Regeneration cost was tentatively evaluated. (author)

  13. Effects of electron beam irradiation on tin dioxide gas sensors

    Indian Academy of Sciences (India)

    WINTEC

    sensitivity increases more rapidly under high doses of irra- diation than under low doses of irradiation. The electron beam irradiation effects were simulated and the mecha- nism was discussed. Acknowledgements. The authors gratefully acknowledge financial support from the MOST 973 program, grant no. 2006CB705604 ...

  14. Space-charge dynamics of polymethylmethacrylate under electron beam irradiation

    CERN Document Server

    Gong, H; Ong, C K

    1997-01-01

    Space-charge dynamics of polymethylmethacrylate (PMMA) under electron beam irradiation has been investigated employing a scanning electron microscope. Assuming a Gaussian space-charge distribution, the distribution range (sigma) has been determined using a time-resolved current method in conjunction with a mirror image method. sigma is found to increase with irradiation time and eventually attain a stationary value. These observations have been discussed by taking into account radiation-induced conductivity and charge mobility. (author)

  15. 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.)

  16. Waste treatment by microwave and electron beam irradiation

    International Nuclear Information System (INIS)

    Martin, D.; Craciun, G.; Manaila, E.; Ighigeanu, D; Oproiu, C.; Iacob, N.; Togoe, I.; Margaritescu, I.

    2007-01-01

    Comparative results obtained by applying separate and combined (successive and simultaneous) electron beam (EB) and microwave (MW) irradiation to waste treatment, such as food residuals (minced beef, wheat bran and wheat flour) and sewage sludge performed from a food industry wastewater treatment station (vegetable oil plant), are presented. The research results demonstrated that the simultaneous EB and MW irradiation produces the biggest reduction of microorganisms. The tests also demonstrated that the irradiation time and the upper limit of required EB absorbed dose, which ensures a complete sterilization effect, could be reduced by a factor of two by an additional use of MW energy to EB irradiation

  17. Sterilization of ground spices by electron beams irradiation

    International Nuclear Information System (INIS)

    Hashigiwa, Masayuki; Nakachi, Ayako; Kobayashi, Hiroshi

    1999-01-01

    Each ground spice (Black Pepper, Turmeric, Ginger, Paprika and Basil), which was packaged into polyethylene film, was irradiated by electron beams at 5 different levels: 2, 4, 6, 8 and 10 kGy. Bacteriological tests for total bacterial count were carried out on spices before and after irradiation, but the tests for microfiora were carried out only before irradiation. Total bacterial count decreased in proportion to the level of electron beams. But the decreasing rate for Turmeric, Ginger and Basil was lower compared with that of other spices. The reason seems that rate of contamination by B. pumilus, which is thought as radiation resistant bacteria, was higher on these spices. (author)

  18. Sterilization of ground spices by electron beams irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hashigiwa, Masayuki; Nakachi, Ayako; Kobayashi, Hiroshi [K. Kobayashi and Co., Ltd., Kako, Hyogo (Japan)

    1999-09-01

    Each ground spice (Black Pepper, Turmeric, Ginger, Paprika and Basil), which was packaged into polyethylene film, was irradiated by electron beams at 5 different levels: 2, 4, 6, 8 and 10 kGy. Bacteriological tests for total bacterial count were carried out on spices before and after irradiation, but the tests for microfiora were carried out only before irradiation. Total bacterial count decreased in proportion to the level of electron beams. But the decreasing rate for Turmeric, Ginger and Basil was lower compared with that of other spices. The reason seems that rate of contamination by B. pumilus, which is thought as radiation resistant bacteria, was higher on these spices. (author)

  19. The reaction rates of electrons with native and irradiated ribonuclease

    International Nuclear Information System (INIS)

    Schuessler, H.; Ebert, M.; Davies, J.V.

    1977-01-01

    The rate of reaction of hydrated electrons with proteins depends, amongst other things, on the conformational structure of the protein, and irradiation itself causes conformational changes in proteins. A study has been made of variations in the reaction rates of hydrated electrons with RNase pre-irradiated by the Linac or by a 60 Co γ-source. The reaction rate constants varied with the pre-irradiation dose, the concentration of phosphate buffer, the enzyme concentration and also the presence of 10 -2 M ethanol. These variations serve to emphasize the importance of the tertiary structure of biological molecules in irradiation processes and have significant implications in the mathematical analysis of the inactivation of enzymes in steady-state irradiation processes. (U.K.)

  20. Strengthening of Poly Methyl Methacrylate (PMMA) through Electron Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Sung Ho; Lim, Hyung San; Ha, Jun Mok; Cho, Sung Oh [KAIST, Daejeon (Korea, Republic of)

    2015-05-15

    Poly Methyl Methacrylate (PMMA) was previously known to show the deteriorating mechanical properties when irradiated with electrons. This is true for low electron irradiation does, but it was found, through experimentation, that at high irradiation dose, PMMA demonstrates improved mechanical properties. With enough electron irradiation dose, the scissions can form new links amongst one another to achieve stability that surpasses that of the PMMA in pre-irradiation treatment state. With higher irradiation dosage and beam strength, hardness of irradiated PMMA could be increased to a much greater extent. Electrons with 50keV of energy can only penetrate around 30 μm of PMMA, thus increasing the beam energy could potentially allow for hardening of not just the surface of the PMMA samples, but the whole samples themselves. Furthermore, Pencil Hardness Test is a method to roughly analyze a material's hardness and does not provide an accurate feedback on the mechanical properties of the material of interest. Hence, a more thorough and effective method of measuring data from the use of equipment such as IZOD Impact Tester, Strain-Stress Tester and Haze Meter will be utilized in the future.

  1. Application of electron beam irradiation, (1). Development and application of electron beam processors

    International Nuclear Information System (INIS)

    Katsumura, Yosuke

    1994-01-01

    This paper deals with characteristics, equipment (principle and kinds), present conditions, and future issues in the application of electron beam irradiation. Characteristics of electron beams are described in terms of the following: chemical and biological effects of radiation; energy and penetrating power of electron beams; and principle and kinds of electron beam accelerator. Industrial application of electron beam irradiation has advantages of high speed procedure and producibility, less energy, avoidance of poisonous gas, and extreme reduction of organic solvents to be used. The present application of electron beam irradiation cen be divided into the following: (1) hardening of resin or coated membrane; (2) improvement of macromolecular materials; (3) environmental protection; (4) sterilization; (5) food sterilization. The present equipment for electron beam irradiation is introduced according to low energy, medium energy, and high energy equipment. Finally, future issues focuses on (1) the improvement of traceability system and development of electron dosimetric techniques and (2) food sterilization. (N.K.)

  2. Pollen morphology of the Alangiaceae

    NARCIS (Netherlands)

    Reitsma, Tj.

    1970-01-01

    This paper presents a pollen-morphological study of Alangium, a genus mainly restricted to the tropics of the Old World, of which 18 of the 19 known species were studied. The pollen grains, studied with the use of a light microscope, a transmission electron microscope and a scanning electron

  3. Comparison of Different Methods for Separation of Haploid Embryo Induced through Irradiated Pollen and Their Economic Analysis in Melon (Cucumis melo var. inodorus

    Directory of Open Access Journals (Sweden)

    Gökhan Baktemur

    2013-01-01

    Full Text Available Irradiated pollen technique is the most successful haploidization technique within Cucurbitaceae. After harvesting of fruits pollinated with irradiated pollen, classical method called as “inspecting the seeds one by one” is used to find haploid embryos in the seeds. In this study, different methods were used to extract the embryos more easily, quickly, economically, and effectively. “Inspecting the seeds one by one” was used as control treatment. Other four methods tested were “sowing seeds direct nutrient media,” “inspecting seeds in the light source,” “floating seeds on liquid media,” and “floating seeds on liquid media after surface sterilization.” Y2 and Y3 melon genotypes selected from the third backcross population of Yuva were used as plant material. Results of this study show that there is no statistically significant difference among methods “inspecting the seeds one by one,” “sowing seeds direct CP nutrient media,” and “inspecting seeds in the light source,” although the average number of embryos per fruit is slightly different. No embryo production was obtained from liquid culture because of infection. When considered together with labor costs and time required for embryo rescue, the best methods were “sowing seeds directly in the CP nutrient media“ and ”inspecting seeds in the light source.”

  4. Electrical properties of gallium arsenide irradiated with electrons and neutrons

    International Nuclear Information System (INIS)

    Kol'chenko, T.I.; Lomako, V.M.

    1975-01-01

    A study was made of changes in the electrical properties of GaAs doped with Te, S, Se, Si, Ge, Sn (n 0 approximately 10 16 -10 18 cm -3 ) and irradiated either with 2.5-28 MeV electrons or with fast reactor neutrons. An analysis of changes in the electron density indicated that the rate of carrier removal by electron bombardment was independent of the dopant but was governed by isolated radiation defects. The change in the mobility due to irradiation with 2.5-10 MeV electrons was also governed by isolated defects. When the electron energy was increased to 28 MeV the main contribution to the change in the mobility was made by defect clusters. In the neutron-irradiation case the changes in the carrier density and mobility were mainly due to defect clusters and the nature of changes in the electrical properties was again independent of the dopant

  5. Electron irradiation effect on single crystal of niobium

    International Nuclear Information System (INIS)

    Otero, M.P.; Lucki, G.

    1984-01-01

    The effect of electron irradiation (900 KeV) on gliding dislocations of single crystal Nb with its tensile axe in the [941] orientation was observed for the in-situ deformation in a high voltage electron microscope (HVEM) at Argonne National Laboratory. The experimental was carried out by the 1 hour-electron irradiation with no stress applied. Straight dislocations actuating as sinks for the electron produced defects became helicoidal as the irradiation proceeded. Frenkel pairs were created in Nb for electron energies > = 650 KeV and, as the single vacancies do not undergo long-range migration in Nb at temperatures much below 620 K, the defects that are entrapped by the dislocations are self-interstitials produced by electron displacement. Applying the stress it was possible to observe that modified dislocations did not glide while the dislocations not affected by the irradiation are visibly in movement. This important result explains the neutron and electron-irradiation induced work-hardening effect for Nb that was previously observed. (Author) [pt

  6. Electron microscope study of irradiated beryllium oxide

    International Nuclear Information System (INIS)

    Bisson, A.A.

    1965-06-01

    The beryllium oxide is studied first by fractography, before and after irradiation, using sintered samples. The fractures are examined under different aspects. The higher density sintered samples, with transgranular fractures are the most interesting for a microscopic study. It is possible to mark the difference between the 'pores' left by the sintering process and the 'bubbles' of gases that can be produced by former thermal treatments. After irradiation, the grain boundaries are very much weakened. By annealing, it is possible to observe the evolution of the gases produced by the reaction (n, 2n) and (n. α) and gathered on the grain boundaries. The irradiated beryllium oxide is afterwards studied by transmission. For that, a simple method has been used: little chips of the crushed material are examined. Clusters of point defects produced by neutrons are thus detected in crystals irradiated at the three following doses: 6 x 10 19 , 9 x 10 19 and 2 x 10 20 n f cm -2 at a temperature below 100 deg. C. For the irradiation at 6 x 10 19 n f cm -2 , the defects are merely visible, but at 2 x l0 20 n f cm -2 the crystals an crowded with clusters and the Kikuchi lines have disappeared from the micro-diffraction diagrams. The evolution of the clusters into dislocation loops is studied by a series of annealings. The activation energy (0,37 eV) calculated from the annealing curves suggests that it must be interstitials that condense into dislocation loops. Samples irradiated at high temperatures (650, 900 and 1100 deg. C) are also studied. In those specimens the size of the loops is not the same as the equilibrium size obtained after out of pile annealing at the same temperature. Those former loops are more specifically studied and their Burgers vector is determined by micro-diffraction. (author) [fr

  7. Elemental process of amorphization induced by electron irradiation in Si

    International Nuclear Information System (INIS)

    Yamasaki, Jun; Takeda, Seiji; Tsuda, Kenji

    2002-01-01

    We recently found that amorphization is induced in Si by electron irradiation. Examining the amorphization systematically, we have established the diagram of steady states under electron irradiation, either amorphous Si (a-Si) or crystalline Si (c-Si) as a function of incident electron energy, electron dose, and irradiation temperature. Utilizing transmission electron microscopy, electron energy filtered diffraction and electron energy-loss spectroscopy, we have characterized the atomic structure, the electronic structure, and the thermal stability of a-Si induced by electron irradiation. Based on the experimental data, we have also concluded that the amorphization is caused by the accumulation of not point defects but small cascade damages. Analyzing the change in the intensity of halo diffraction rings during amorphization, we have clarified that the smallest cascade damage that contributes to amorphization includes only about four Si atoms. This presumably supports the amorphization mechanism that four self-interstitial atoms form the quasistable structure I4 in c-Si and it becomes an amorphous embryo

  8. Paraelasticity in electron-irradiated molybdenum

    International Nuclear Information System (INIS)

    Beuneu, Brigitte; Quere, Yves.

    1981-11-01

    The relaxation of a radiation-induced point defect-most probably the rotation of a dumbell-is observed during isothermal anneals of irradiated molybdenum by resistivity measurements. The recovery of close pairs is not affected, in first analysis, by the presence of a uniaxial stress

  9. Electron microscopy at reduced levels of irradiation

    International Nuclear Information System (INIS)

    Kuo, I.A.M.

    1975-05-01

    Specimen damage by electron radiation is one of the factors that limits high resolution electron microscopy of biological specimens. A method was developed to record images of periodic objects at a reduced electron exposure in order to preserve high resolution structural detail. The resulting image would tend to be a statistically noisy one, as the electron exposure is reduced to lower and lower values. Reconstruction of a statistically defined image from such data is possible by spatial averaging of the electron signals from a large number of identical unit cells. (U.S.)

  10. Polymerization of vinyl stearate multilayers by electron beam irradiation

    International Nuclear Information System (INIS)

    Nishii, Masanobu; Hatada, Motoyoshi

    1975-01-01

    Studies on the radiation-induced polymerization of vinyl stearate (VST) multilayers were carried out. The VST multilayers built-up on an aluminum plated glass plate by Langmuir-Blodgett technique were irradiated with electron beams from a Van de Graaff electron accelerator in nitrogen atmosphere. The structure of the multilayers and the effects of irradiation were investigated by X-ray diffractometry, contact angle measurement, multireflection infrared spectroscopy, and scanning electron microscopy. The VST multilayers became insoluble to methanol by the irradiation, and the multi-reflection infrared spectrum of the VST multilayers turned into that of poly (VST) with increasing dosage. The polymerization proceeded during the irradiation at the temperature range between -10 0 and 10 0 C, and the conversion attained to 90% within 2.5 minutes (total dose, 5.6 Mrads). The multilayers irradiated above 13 Mrads turned into the polymer film insoluble to benzene, indicating that the polymer chains were cross-linked by the irradiation. Stearic acid which was formed by the irradiation of VST at nitrogen-water interface as a hydrolysis product was not detected in this system. (auth.)

  11. Postharvest quality of cut roses following electron-beam irradiation

    International Nuclear Information System (INIS)

    Chang, A.Y.; Gladon, R.J.; Gleason, M.L.; Parker, S.K.; Agnew, N.H.; Olson, D.G.

    1997-01-01

    Cut Rosa x hybrida L. 'Royalty' flowers were used to determine the efficacy of electron-beam irradiation for increasing postharvest quality and decreasing petal infection by Botrytis cinerea Pers. In an experiment for determining the injury threshold, roses received electron-beam irradiation of 0, 0.5, 1, 2, and 4 kGy. Irradiation dosages greater than or equal to 4 kGy caused necrosis on petal tissue and decreased postharvest life at 20 degrees C. In a second experiment to evaluate postharvest quality, roses were irradiated at 0, 0.25, 0.5, 0.75, and 1 kGy. Dosages of 0.25 and 0.5 kGy slowed the rate of flower bud opening for 2 days but did not decrease postharvest quality when compared with nonirradiated roses. Roses that received irradiation dosages of 0.75 and 1 kGy showed unacceptable quality. In a third experiment, roses that had or had not been inoculated with B. cinerea were irradiated at 0, 0.25, 0.5, and 0.75 kGy. Irradiation did not control B. cinerea populations, and rose quality decreased as dosage increased. In a fourth experiment to determine the effect of irradiation on B. cinerea, conidia on water-agar plates exposed to dosages less than or equal to 1, 2, and 4 kGy germinated at rates of approximately 90%, 33%, and 2%, respectively, within 24 h

  12. Preparation of PbSe nanoparticles by electron beam irradiation

    Indian Academy of Sciences (India)

    A novel method has been developed by electron beam irradiation to prepare PbSe nanoparticles. 2 MeV 10mA GJ-2-II electronic accelerator was used as radiation source. Nanocrystalline PbSe was prepared rapidly at room temperature under atmospheric pressure without any kind of toxic reagents. The structure and ...

  13. Silver nanoparticles: synthesis and size control by electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bogle, K A; Dhole, S D; Bhoraskar, V N [Microtron Accelerator Laboratory, Department of Physics, University of Pune, Pune-411007 (India)

    2006-07-14

    Silver nanoparticles were synthesized by irradiating solutions, prepared by mixing AgNO{sub 3} and poly-vinyl alcohol (PVA), with 6 MeV electrons. The electron-irradiated solutions and the thin coatings cast from them were characterized using the ultraviolet-visible (UV-vis), x-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques. During electron irradiation, the process of formation of the silver nanoparticles appeared to be initiated at an electron fluence of {approx}2 x 10{sup 13} e cm{sup -2}. This was evidenced from the solution, which turned yellow and exhibited the characteristic plasmon absorption peak around 455 nm. Silver nanoparticles of different sizes in the range 60-10 nm, with a narrow size distribution, could be synthesized by varying the electron fluence from 2 x 10{sup 13} to 3 x 10{sup 15} e cm{sup -2}. Silver nanoparticles of sizes in the range 100-200 nm were also synthesized by irradiating an aqueous AgNO{sub 3} solution with 6 MeV electrons.

  14. Radiation defects in electron-irradiated InP crystals

    International Nuclear Information System (INIS)

    Brailovskii, E.Yu.; Karapetyan, F.K.; Megela, I.G.; Tartachnik, V.P.

    1982-01-01

    The results are presented of formation and annealing of defects in InP crystals at 1 to 50 MeV electron irradiation. The recovery of electrical properties in the range of 77 to 970 K during annealing processes is studied. Five low temperature annealing states in n-InP and the reverse annealing in p-InP are observed at 77 to 300 K. Four annealing stages at temperatures higher than 300 K are present. When the electron energy is increased more complicated thermostable defects are formed, and at 50 MeV electron energy besides of the point defect clusters are formed, which anneal at temperatures of 800 to 970 K. It is shown that the peculiarities of the Hall mobility at irradiation and annealing are caused by the scattering centres E/sub c/ - 0.2 eV. The 'limiting' position of the Fermi level in electron irradiated InP crystals is discussed. (author)

  15. 'The future of the electron beam irradiation service business'

    International Nuclear Information System (INIS)

    Yamase, Yutaka

    1998-01-01

    The high energy electron beam has less penetration power in comparison with the gamma ray which has been used from before. However, the dose rate of the electron beam is considerably high in comparison with the gamma ray with more than several thousand times. Therefore, the irradiation of the product can be done in a short time, and there are cheap characteristics further in the irradiation cost as well. And, an electron beam is the technology which is very easy to accept in the country of a nuclear allergy constitution like our country so that it may not use radioactive substance. This time, I'd like to think about the present condition of the electron beam irradiation service business and a future based on the experience of Tsukuba EBcenter until now. (J.P.N.)

  16. Electron beam dosimetry for a thin-layer absorber irradiated by 300-keV electrons

    International Nuclear Information System (INIS)

    Kijima, Toshiyuki; Nakase, Yoshiaki

    1993-01-01

    Depth-dose distributions in thin-layer absorbers were measured for 300-keV electrons from a scanning-type irradiation system, the electrons having penetrated through a Ti-window and an air gap. Irradiations of stacks of cellulose triacetate(CTA) film were carried out using either a conveyor (i.e. dynamic irradiation) or fixed (i.e. static) irradiation. The sample was irradiated using various angles of incidence of electrons, in order to examine the effect of obliqueness of electron incidence at low-energy representative of routine radiation curing of thin polymeric or resin layers. Dynamic irradiation gives broader and shallower depth-dose distributions than static irradiation. Greater obliqueness of incident electrons gives results that can be explained in terms of broader and shallower depth-dose distributions. The back-scattering of incident electrons by a metal(Sn) backing material enhances the absorbed dose in a polymeric layer and changes the overall distribution. It is suggested that any theoretical estimations of the absorbed dose in thin layers irradiated in electron beam curing must be accomplished and supported by experimental data such as that provided by this investigation. (Author)

  17. Behaviour of some fresh fruits under electron-beam irradiation

    International Nuclear Information System (INIS)

    Ferdes, O.; Stroia, A.L.; Potcoava, A.; Cojocaru, M.; Mihnea, R.; Oproiu, C.

    1994-01-01

    The use of ionizing radiation in preservation of fruits and vegetables is widely recognized. In this paper it is presented a study of the effect of electron-beam irradiation of some fresh, early and perishable fruits, like strawberries, cherries, and sour cherries concerning their shelf-life time extension. The irradiations were performed on common varieties in normal conditions to the IPTRD's electron-beam accelerator (Bucharest-Magurele) having the following parameters: flow current 10 μA, power 60 W and electron mean energy 6.23 MeV. The irradiation doses varied between 0.5-3.0 kGy and the dose rates between 100-1500 Gy/min. It was observed the fruit preservation capability of the treatment and it was analysed the main characteristics as organoleptic properties, weight of dry component, acidity, total and reducing sugars, ascorbic acid content and others. It was evidenced an increase in freshness and shelf-life extension by 5-7 days for strawberries and up to two weeks for cherries without any significant changes in the values of the considered parameters. Otherwise, for the applied doses, the electron-beam irradiation did not produce any significant changes in the values of fruit characteristic parameters. The results lead to the conclusion that the electron-beam irradiation is a good technological solution for fresh fruit processing. (Author) 1 Tab., 7 Refs

  18. Electron beam irradiation of gemstone for color enhancement

    Science.gov (United States)

    Idris, Sarada; Ghazali, Zulkafli; Hashim, Siti A'iasah; Ahmad, Shamshad; Jusoh, Mohd Suhaimi

    2012-09-01

    Numerous treatment of gemstones has been going on for hundreds of years for enhancing color and clarity of gems devoid of these attributes. Whereas previous practices included fraudulent or otherwise processes to achieve the color enhancement, the ionizing radiation has proven to be a reliable and reproducible technique. Three types of irradiation processes include exposure to gamma radiation, electron beam irradiation and the nuclear power plants. Electron Beam Irradiation of Gemstone is a technique in which a gemstone is exposed to highly ionizing radiation electron beam to knock off electrons to generate color centers culminating in introduction of deeper colors. The color centers may be stable or unstable. Below 9MeV, normally no radioactivity is introduced in the exposed gems. A study was conducted at Electron Beam Irradiation Centre (Alurtron) for gemstone color enhancement by using different kind of precious gemstones obtained from Pakistan. The study shows that EB irradiation not only enhances the color but can also improves the clarity of some type of gemstones. The treated stones included kunzite, tourmaline, topaz, quartz, aquamarine and cultured pearls. Doses ranging from 25 kGy to 200 KGy were employed to assess the influence of doses on color and clarity and to select the optimum doses. The samples used included both the natural and the faceted gemstones. It is concluded that significant revenue generation is associated with the enhancement of the color in clarity of gemstones which are available at very cheap price in the world market.

  19. Electron beam irradiation of gemstone for color enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Idris, Sarada; Ghazali, Zulkafli; Hashim, Siti A' iasah; Ahmad, Shamshad; Jusoh, Mohd Suhaimi [Malaysian Nuclear Agency, Bangi, Selangor (Malaysia); School of Chemicals and Material Engineering, NUST Islamabad (Pakistan); Malaysian Nuclear Agency, Bangi, Selangor (Malaysia)

    2012-09-26

    Numerous treatment of gemstones has been going on for hundreds of years for enhancing color and clarity of gems devoid of these attributes. Whereas previous practices included fraudulent or otherwise processes to achieve the color enhancement, the ionizing radiation has proven to be a reliable and reproducible technique. Three types of irradiation processes include exposure to gamma radiation, electron beam irradiation and the nuclear power plants. Electron Beam Irradiation of Gemstone is a technique in which a gemstone is exposed to highly ionizing radiation electron beam to knock off electrons to generate color centers culminating in introduction of deeper colors. The color centers may be stable or unstable. Below 9MeV, normally no radioactivity is introduced in the exposed gems. A study was conducted at Electron Beam Irradiation Centre (Alurtron) for gemstone color enhancement by using different kind of precious gemstones obtained from Pakistan. The study shows that EB irradiation not only enhances the color but can also improves the clarity of some type of gemstones. The treated stones included kunzite, tourmaline, topaz, quartz, aquamarine and cultured pearls. Doses ranging from 25 kGy to 200 KGy were employed to assess the influence of doses on color and clarity and to select the optimum doses. The samples used included both the natural and the faceted gemstones. It is concluded that significant revenue generation is associated with the enhancement of the color in clarity of gemstones which are available at very cheap price in the world market.

  20. Electron beam irradiation of gemstone for color enhancement

    International Nuclear Information System (INIS)

    Idris, Sarada; Ghazali, Zulkafli; Hashim, Siti A'iasah; Ahmad, Shamshad; Jusoh, Mohd Suhaimi

    2012-01-01

    Numerous treatment of gemstones has been going on for hundreds of years for enhancing color and clarity of gems devoid of these attributes. Whereas previous practices included fraudulent or otherwise processes to achieve the color enhancement, the ionizing radiation has proven to be a reliable and reproducible technique. Three types of irradiation processes include exposure to gamma radiation, electron beam irradiation and the nuclear power plants. Electron Beam Irradiation of Gemstone is a technique in which a gemstone is exposed to highly ionizing radiation electron beam to knock off electrons to generate color centers culminating in introduction of deeper colors. The color centers may be stable or unstable. Below 9MeV, normally no radioactivity is introduced in the exposed gems. A study was conducted at Electron Beam Irradiation Centre (Alurtron) for gemstone color enhancement by using different kind of precious gemstones obtained from Pakistan. The study shows that EB irradiation not only enhances the color but can also improves the clarity of some type of gemstones. The treated stones included kunzite, tourmaline, topaz, quartz, aquamarine and cultured pearls. Doses ranging from 25 kGy to 200 KGy were employed to assess the influence of doses on color and clarity and to select the optimum doses. The samples used included both the natural and the faceted gemstones. It is concluded that significant revenue generation is associated with the enhancement of the color in clarity of gemstones which are available at very cheap price in the world market.

  1. Bulk and interface defects in electron irradiated InP

    International Nuclear Information System (INIS)

    Peng Chen; Sun Heng-hui

    1989-01-01

    Systematic studies on the structure of defects in InP caused by electron irradiation are conducted based on experimental measurements and theoretical calculations. The rates of introduction and annealing-out temperatures of In and P vancancies are estimated using proper theoretical models. These calculations reveal that after room temperature irradiation only complexes may exist. It is also supported by our experimental data that the sum of introducing rates of three detected levels are less than the theoretical value calculated for single vacancies. According to our equation on the relation between interface states and DLTS signal and from the results of computer calculation we believe that the broad peak appearing in the DLTS diagram before irradiation is related to interface states. Its disappearance after electron irradiation suggests the reduction of interface states; this is further confirmed by the reduction of surface recombination rate derived from the results of surface photovoltage measurement

  2. Manufacture of electron beam irradiation vessel and its characteristics

    International Nuclear Information System (INIS)

    Kanazawa, Takao; Haruyama, Yasuyuki; Yotsumoto, Keiichi

    1992-05-01

    Electron beam irradiation vessel, which is used for the irradiation of samples under an inert or a vacuum atmosphere, is made by considering the temperature control during or after irradiation. The vessel was composed of the temperature controlable samples supporting plate, beam slit with water cooling plate and the insert of thermosensor. The four samples supporting plate was produced with the materials made up of aluminium, stainless steel (SUS304), and copper. The stainless steel supporting plate has a heater inside the cooling pipes for the high temperature treatment of samples without exposure to atmosphere after the irradiation. In this report, the temperature distribution and dose characteristics such as dose distribution and effects of backscattered electron were studied by using several supporting plate and the comparison of the experimental results with the simulated results was also carried out. (author)

  3. Analytical electron microscopy of neutron-irradiated reactor alloys

    International Nuclear Information System (INIS)

    Thomas, L.E.

    1982-01-01

    Exposure to the high neutron fluxes and temperatures from 400 to 650 0 C in the core region of a fast breeder reactor profoundly alters the microstructure and properties of structural steels and superalloys. The development of irradiation-induced voids, dislocations and precipitates, as well as segregation of alloying elements on a microscopic scale has been related to macroscopic swelling, creep, hardening and embrittlement which occur during prolonged exposures in reactor. Microanalytical studies using TEM/STEM methods, primarily energy dispersive x-ray (EDX) microanalysis, have greatly aided understanding of alloy behavior under irradiation. The main uses of analytical electron microscopy in studying irradiated alloys have been the identification of irradiation-induced precipitates and determination of the changes in local composition due to irradiation-induced solute segregation

  4. Electron beam irradiation effect on nanostructured molecular sieve catalysts

    International Nuclear Information System (INIS)

    Yuan Zhongyong; Zhou Wuzong; Parvulescu, Viorica; Su Baolian

    2003-01-01

    Electron impact can induce chemical changes on particle surfaces of zeolites and molecular sieve catalysts. Some experimental observations of electron irradiation effect on molecular sieve catalysts are presented, e.g., electron-beam-induced growth of bare silver nanowires from zeolite crystallites, formation of vesicles in calcium phosphate, migration of microdomains in iron-oxide doped mesoporous silicas, structural transformation from mesostructured MCM-41 to microporous ZSM-5, etc. The formation mechanisms of the surface structures are discussed

  5. Clarification of leachate from reclaimed ground by electron beam irradiation

    International Nuclear Information System (INIS)

    Yamazaki, Masao; Sawai, Teruko; Shimokawa, Toshinari; Sawai, Takeshi

    1985-01-01

    To decompose organic matters such as humic acid and fulvous acid in the leachate from reclaimed ground, an electron beam irradiation technique was examined because of availability of higher dose rate than a 60 Co γ-ray source. This paper describes results of the above-mentioned preliminary examination. Test water was collected from No.15 dumping site at the Tokyo Bay. Irradiation sample was prepared by filtration with a filter and decarbonation with sulfuric acid. Fulvous acid solution by eliminating humic acid was also served for the examination. Electron beam irradiation of the sample solution was made with a Van de Graaf accelerator by 1.5 MeV, 140 Gy/sec of irradiation condition and with a dynamitron by 2.0 MeV, 25 kGy/pass of the condition. It was clarified that oxygen bubbling velocity during the irradiation did not affect much for the decrease rate of total organic matters (TOC) within 0.5 to 3.0 1/min of an experimental condition. As for radiation doses and TOC decrease, TOC was decreased much for lower dose rate irradiation (Van de Graaf accelerator), lower initial TOC concentration, or addition of hydrogen peroxide. For the combined treatment of radiation and flocculation to aim at irradiation dose decrease, fulvous acid solution was served for the test. Lower dose irradiation with a 60 Co source showed better TOC elimination and it was concluded that combination with flocculation was effective for the dose reduction. It was also found experimentally that TOC decrease behavior by the both radiation source was different due to temperature effect and further study should be made for the development of the practical electron beam irradiation technique. (Takagi, S.)

  6. (100) faceted anion voids in electron irradiated fluorite

    International Nuclear Information System (INIS)

    Johnson, E.

    1979-01-01

    High fluence electron irradiation of fluorite crystals in the temperature range 150 to 320 K results in formation of a simple cubic anion void superlattice. Above 320 K the damage structure changes to a random distribution of large [001] faceted anion voids. This voidage behaviour, similar to that observed in a range of irradiated metals, is discussed in terms points defect rather than conventional colour centre terminology. (Auth.)

  7. Void shrinkage in stainless steel during high energy electron irradiation

    International Nuclear Information System (INIS)

    Singh, B.N.; Foreman, A.J.E.

    1976-03-01

    During irradiation of thin foils of an austenitic stainless steel in a high voltage electron microscope, steadily growing voids have been observed to suddenly shrink and disappear at the irradiation temperature of 650 0 Cthe phenomenon has been observed in specimens both with and withoutimplanted helium. Possible mechanisms for void shrinkage during irradiation are considered. It is suggested that the dislocation-pipe-diffusion of vacancies from or of self-interstitial atoms to the voids can explain the shrinkage behaviour of voids observed during our experiments. (author)

  8. Electronic control system for irradiation probes

    International Nuclear Information System (INIS)

    Gluza, E.; Neumann, J.; Zahalka, F.

    1980-01-01

    The EROS-78 system for the supply and power control of six heating sections of the irradiation probe of the CHOUCA type placed in the reactor vessel is described. The system allows temperature control at the location of the heat sensor with an accuracy of +-1% of the rated value within the region of 100 to 1000 degC. The equipment is provided with its own quartz controlled clock. The temperature is picked up by a chromel-alumel jacket thermocouple. The power input of the heating elements is thyristor controlled. (J.B.)

  9. Effects of electron irradiation on LDPE/MWCNT composites

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jianqun [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Li, Xingji, E-mail: lxj0218@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Liu, Chaoming; Rui, Erming [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Wang, Liqin [School of Mechatronics, Harbin Institute of Technology, Harbin 150001 (China)

    2015-12-15

    In this study, mutiwalled carbon nanotubes (MWCNTs) were incorporated into low density polyethylene (LDPE) in different concentrations (2%, 4% and 8%) using a melt blending process. Structural, thermal stability and tensile property of the unirradiated/irradiated LDPE/MWCNT composites by 110 keV electrons were investigated by means of scanning electron microscopy (SEM), small angle X-ray scattering (SAXS), Raman spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, thermogravimetric analysis (TGA) and uniaxial tensile techniques. Experimental results show that the addition of MWCNTs obviously increases the ultimate tensile strength of LDPE and decreases the elongation at break, which is attributed to the homogeneous distribution of the MWCNTs in LDPE and intense interaction between MWCNTs and LDPE matrix. Also, the electron irradiation further increases the ultimate tensile strength of LDPE/MWCNT composites, which can be ascribed to the more intense interaction between MWCNTs and LDPE matrix, and the formation of crosslinking sites in LDPE matrix induced by the electron irradiation. The addition of MWCNTs significantly enhances thermal stability of the LDPE due to the hindering effect and the scavenging free radicals, while the electron irradiation decreases thermal stability of the LDPE/MWCNT composites since the structure of the MWCNTs and LDPE matrix damages.

  10. Radiosensitivity of chlorella after medium energy accelerated electron irradiation

    International Nuclear Information System (INIS)

    Roux, J.C.

    1966-06-01

    The survival curves (capability of multiplication) of chlorella pyrenoidosa after irradiations can be used for soft electrons (0.65 and 1 MeV), hence penetrating into only 2 to 4 millimeters of water: the algae are laying on porous membranes and the doses are calculated from the power of the electron beam measured by the electric current on a metallic target or by Fricke's dosimetry. With these techniques, it is showed and discussed the part of anoxia in the radioprotection (magnitude or reduction of the dose calculated from the slope of survival curves: 2.5 ) that is more important than the restoration studied by the fractionation of the dose. The 0.65 and 1 MeV electrons have a biologic effect lesser than 180 keV X-rays (RBE - relative biological efficiency - calculated on the slope of survival curves is 0.92 in aerated irradiation, 0.56 in the deoxygenated irradiation). (author) [fr

  11. Degradation behaviour of fiber reinforced plastic under electron beam irradiation

    International Nuclear Information System (INIS)

    Sonoda, Katsumi; Yamamoto, Yasushi; Hashimoto, Osamu

    1989-01-01

    Various mechanical properties of four kinds of glass fiber-reinforced plastics irradiated with electron beams were examined at three temperatures; room temperature, 123 K and 77 K. Dynamic viscoelastic properties were measured, and fractography by means of scanning electron microscopy was observed in order to clarify degradation behaviour. A considerable decrease in interlaminar shear strength (ILSS) at room temperature was observed above 60 MGy. On the other hand, the three-point bending strength at 77 K and the ILSS at 123 K decreased with increasing irradiation. Fractography reveals that the degradation of the interface layer between matrix resin and fiber plays an important role in the strength reduction at 123 K and 77 K. These findings suggest that the interface between matrix resin and fiber loses its bondability at 123 K arid 77 K after electron beam irradiation. (author)

  12. Electron beam irradiation effect on GaN HEMT

    International Nuclear Information System (INIS)

    Lou Yinhong; Guo Hongxia; Zhang Keying; Wang Yuanming; Zhang Fengqi

    2011-01-01

    In this work, GaN HEMTs (High Electron Mobility Transistor) were irradiated by 0.8 and 1.2 MeV electron beams, and the irradiation effects were investigated. The results show that the device damage caused by 0.8 MeV electrons is more serious than that by 1.2 MeV electrons. Saturation drain current increase and threshold voltage negative shift are due to trapped positive charge from ionization in the AlGaN layer and N, Ga vacancy from non-ionizing energy loss in the GaN layer. Electron traps and trapped positive charges from non-ionizing in the AlGaN layer act as trap-assisted-tunneling centers that increase the gate leakage current.(authors)

  13. The use of electron accelerators for fresh fruit irradiation

    International Nuclear Information System (INIS)

    Ferdes, O.; Minea, R.

    2000-01-01

    There are presented the results of tests concerning the effects of accelerated electron-beam to some early fresh fruits like strawberries, cherries, sour-cherries and apples. The irradiation were performed on common varieties, in normal conditions, to the NILPRP-Electron Accelerator Laboratory facility consisting in electron-beam accelerators which have the following parameters: - mean beam current, 5 μA; - electron mean energy approximately, 7 MeV; - pulse period, 3.5 μs. The doses varied between 0.5-3.0 kGy and the dose rate was about 1500 Gy/min. It was determined the fruit shelf life and there were analysed the main organoleptic and nutritional properties, as: size, shape, colour, dry weight, acidity, total and reducing sugars, ascorbic acid content and other. For the electron-beam treated fruits it was pointed out an increase in freshness and shelf life extension by 5-7 days for strawberries and more than two weeks for cherries. Otherwise, for the applied doses, the electron-beam irradiation did not produce any significant changes in the fruit characteristic values. These results lead to the conclusion that the electron accelerators could be successfully used as a technological solution for the fresh fruits processing, in view of shelf life extension. There are presented also some technical and economical considerations on the feasibility of this technology and on the use of electron-beam machines for food irradiation. (authors)

  14. Recovery of electron irradiated V-Ga alloys

    International Nuclear Information System (INIS)

    Leguey, T.; Monge, M.; Pareja, R.; Hodgson, E.R.

    2000-01-01

    The recovery characteristics of electron-irradiated V-Ga alloys with 1.2 and 4.6 at.% Ga have been investigated by positron annihilation spectroscopy (PAS). It is found that vacancies created by electron irradiation become mobile in these alloys at ∼293 K. This temperature is noticeably lower than that in pure V and V-Ti alloys. The vacancies aggregate into microvoids in V-4.6Ga, but do not in V-1.2Ga. The results indicate that vacancies are bound to Ga-interstitial impurity pairs

  15. Evolution of graphene nanoribbons under low-voltage electron irradiation

    KAUST Repository

    Zhu, Wenpeng

    2012-01-01

    Though the all-semiconducting nature of ultrathin graphene nanoribbons (GNRs) has been demonstrated in field-effect transistors operated at room temperature with ∼105 on-off current ratios, the borderline for the potential of GNRs is still untouched. There remains a great challenge in fabricating even thinner GNRs with precise width, known edge configurations and specified crystallographic orientations. Unparalleled to other methods, low-voltage electron irradiation leads to a continuous reduction in width to a sub-nanometer range until the occurrence of structural instability. The underlying mechanisms have been investigated by the molecular dynamics method herein, combined with in situ aberration-corrected transmission electron microscopy and density functional theory calculations. The structural evolution reveals that the zigzag edges are dynamically more stable than the chiral ones. Preferential bond breaking induces atomic rings and dangling bonds as the initial defects. The defects grow, combine and reconstruct to complex edge structures. Dynamic recovery is enhanced by thermal activation, especially in cooperation with electron irradiation. Roughness develops under irradiation and reaches a plateau less than 1 nm for all edge configurations after longtime exposure. These features render low-voltage electron irradiation an attractive technique in the fabrication of ultrathin GNRs for exploring the ultimate electronic properties. © 2012 The Royal Society of Chemistry.

  16. Absorption and luminescence of crystalline quartz under electron nanosecond irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gritsenko, B P; Lisitsyn, V M; Stepanchuk, V N [Tomskij Politekhnicheskij Inst. (USSR)

    1981-02-01

    The purpose of the study is continuation of investigations of principal regularities of production and destruction of short-lived defects in quartz and accompanying luminescence under electron pulse irradiation. For investigation purposes samples of crystalline synthetic quartz have been used. The irradiation has been performed at 80-400 K temperatures by means of an electron pulse accelerator with parameters: electron flow pulse duration 10 ns, pulse current density up to 1000 A/cm/sup 2/, electron mean energy 200 keV. Temperature-time characteristics of absorption and luminescence spectrum are studied. It has been found that quartz irradiation by electron pulses of nanosecond duration leads to appearance of short-lived bands of optical absorption at 4.1 and 5.15 eV to which by kinetic parameters correspond luminescence bands at 2.6 and 3.1 eV, respectively. The enumerated absorption bands are induced by quartz irradiation independently of the prehistory and phase state of the sample and are caused obviously by intrinsic radiation defects. Possible models of such defects are suggested.

  17. Evaluation of electron beam irradiation for disinfection of turmeric fingers

    Energy Technology Data Exchange (ETDEWEB)

    Yasumoto, Kyoden; Fujino, Masayuki; Supriyadi (Kyoto Univ., Uji (Japan). Research Inst. for Food Science); Suzuki, Tetsuya; Hayashi, Toru

    1991-08-01

    Turmeric finger as one of the most popular spices has been widely used for food manufacturing. However, it has also been a major cause of bacterial infestation of food materials especially in curry, ham and sausage manufacturing. In this study decontamination of bacteria in turmeric finger by electron beam irradiation was evaluated by comparing with several other decontamination methods: i.e., boiling, microwave irradiation, treatment by twin screw extruder and gamma-ray irradiation. By estimation of colony counting on nutrient agar plate, turmeric finger without any treatment gave total viable cell at 10{sup 8}/g. Turmeric finger which was irradiated by electron beam at 10 kGy dose dramatically reduced thermotolerant cell population below self restriction level (<1000/g), which has been required by food hygiene law. The same level of sterilization effect was obtained only by gamma-ray irradiation at 10 kGy and 20 kGy. On the other hand, although treatment through twin screw extruder slightly reduced bacterial numbers, neither boiling nor microwave irradiation gave sufficient decontamination effect on turmeric fingers. (author).

  18. Evaluation of electron beam irradiation for disinfection of turmeric fingers

    International Nuclear Information System (INIS)

    Yasumoto, Kyoden; Fujino, Masayuki; Supriyadi; Suzuki, Tetsuya; Hayashi, Toru.

    1991-01-01

    Turmeric finger as one of the most popular spices has been widely used for food manufacturing. However, it has also been a major cause of bacterial infestation of food materials especially in curry, ham and sausage manufacturing. In this study decontamination of bacteria in turmeric finger by electron beam irradiation was evaluated by comparing with several other decontamination methods: i.e., boiling, microwave irradiation, treatment by twin screw extruder and gamma-ray irradiation. By estimation of colony counting on nutrient agar plate, turmeric finger without any treatment gave total viable cell at 10 8 /g. Turmeric finger which was irradiated by electron beam at 10 kGy dose dramatically reduced thermotolerant cell population below self restriction level (<1000/g), which has been required by food hygiene law. The same level of sterilization effect was obtained only by gamma-ray irradiation at 10 kGy and 20 kGy. On the other hand, although treatment through twin screw extruder slightly reduced bacterial numbers, neither boiling nor microwave irradiation gave sufficient decontamination effect on turmeric fingers. (author)

  19. Evaluation of electron beam irradiation for disinfection of turmeric fingers

    International Nuclear Information System (INIS)

    Yasumoto, K.; Fujino, M.; Supriyadi; Suzuki, T.; Hayashi, T.

    1991-01-01

    Turmeric finger as one of the most popular spices has been widely used for food manufacturing. However, it has also been a major cause of bacterial infestation of food materials especially in curry, ham and sausage manufacturing. In this study decontamination of bacteria in turmeric finger by electron beam irradiation was evaluated by comparing with several other decontamination methods: i.e., boiling, microwave irradiation, treatment by twin screw extruder and gamma-ray irradiation. By estimation of colony counting on nutrient agar plate, turmeric finger without any treatment gave total viable cell at 10 8 /g. Turmeric finger which was irradiated by electron beam at 10kGy dose dramatically reduced thermotolerant cell population below self restriction level (<1000/g), which has been required by food hygiene law. The same level of sterilization effect was obtained only by gamma-ray irradiation at 10kGy and 20kGy. On the other hand, although treatment through twin screw extruder slightly reduced bacterial numbers, neither boiling nor microwave irradiation gave sufficient decontamination effect on turmeric fingers

  20. 1-Chloronaphthalene decomposition in air using electron beam irradiation

    International Nuclear Information System (INIS)

    Chmielewski, A.G.; Sun, Y.; Bulka, S.; Zimek, Z.

    2006-01-01

    A method for the preparation of model gas containing 1-chloronaphthalene can be referred to 1,1-DCE (dichloroethene). A pulsed electron beam (EB) accelerator ILU-6 (2.0 MeV max., 20 kW max.) was used as an irradiation source. The absorbed dose rate inside the irradiation vessel was 10.835 kGy/min. Total absorbed dose was adjusted by changing irradiation time of the Pyrex glass vessels. 1-Chloronaphthalene concentration was analyzed using gas-chromatography. It has been found, that 1-chloronaphthalene can be decomposed in air or N 2 using EB irradiation. Decomposition efficiency of 1-chloronaphthalene in air is higher than that in N 2 . Positive charge transfer reactions and OH radicals' reaction may play a main role in 1-chloronaphthalene decomposition process

  1. Application of electron irradiation to food containers and packaging materials

    International Nuclear Information System (INIS)

    Ueno, Koji

    2010-01-01

    Problems caused by microbial contamination and hazardous chemicals have attracted much attention in the food industry. The number of systems such as hygienic management systems and Hazard Analysis Critical Control Point (HACCP) systems adopted in the manufacturing process is increasing. As manufacturing process control has become stricter, stricter control is also required for microbial control for containers and packaging materials (from disinfection to sterilization). Since safe and reliable methods for sterilizing food containers and packaging materials that leave no residue are required, electron beam sterilization used for medical equipment has attracted attention from the food industry. This paper describes an electron irradiation facility, methods for applying electron beams to food containers and packaging materials, and products irradiated with electron beams. (author)

  2. Trapped electrons in irradiated single crystals of polyhydroxy compounds

    International Nuclear Information System (INIS)

    Box, H.C.; Budzinski, E.E.; Freund, H.G.; Potter, W.R.

    1979-01-01

    The intermolecular trapping of electrons has been observed in single crystals of dulcitol and L(+) arabinose x-irradiated at 4.2 0 K. Attribution of a major component of the ESR absorption to trapped electrons is based upon the character of the hyperfine pattern, which arises from multiple anisotropic hyperfine interactions with exchangeable protons, and on the g value of the absorption, which is always less than the free spin value. The removal of the trapped electron absorption upon irradiation with visible light has also been demonstrated. In these experiments all of the electrons are trapped in identical sites. This circumstance provides some important advantages in the study of the factors affecting the stabilization of charge in an environment of polarizable molecules

  3. Challenges in validating radiation sterilization with low energy electron irradiation

    International Nuclear Information System (INIS)

    Miller, A.; Helt-Hansen, J.

    2011-01-01

    Complete text of publication follows. Low energy electron irradiation (80-300 keV) is used increasingly for sterilization or decontamination in connection with isolators for aseptic filling lines in the pharmaceutical industry. It is not defined how validation for this process shall be carried out. A method can be derived from the medical device standard for radiation sterilization, ISO 11137, because the principles described in this standard can be applied to almost any industrial irradiation process. The validations elements are: Process definition, concerning specification of the dose required for the process and the maximum acceptable dose for the product. Installation qualification, concerning acceptance the irradiation facility. Operational qualification, concerning characterization of the facility. Performance qualification, concerning setting up the process. Process control, concerning routine monitoring. The limited penetration of the low energy electrons leads to problems with respect to executing these validation steps. This paper discusses these problems, and shows with examples how they can be solved.

  4. Impact of electron irradiation on particle track etching response in ...

    Indian Academy of Sciences (India)

    In the present work, attempts have been made to investigate the modification in particle track etching response of polyallyl diglycol carbonate (PADC) due to impact of 2 MeV electrons. PADC samples pre-irradiated to 1, 10, 20, 40, 60, 80 and 100 Mrad doses of 2 MeV electrons were further exposed to 140 MeV 28Si beam ...

  5. Effects of electron beam irradiation on inorganic exchanger AMP

    International Nuclear Information System (INIS)

    Rao, K.L.N.; Mathew, C.; Deshpande, R.S.; Jadhav, A.V.; Pande, B.M.; Shukla, J.P.

    1996-01-01

    The heteropolyacid salt inorganic exchanger ammonium molybdophosphate (AMP) was subjected to an electron dose upto 2 MGy to assess any possible radiation damage. The breakthrough and total exchange capacity of AMP for Cs + from simulated fission product solutions were determined for both control and irradiated samples. The scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDX) were deployed to examine any marked microscopic changes taking place in this exchanger. (author). 3 refs., 3 figs

  6. A 20 keV electron gun system for the electron irradiation experiments

    International Nuclear Information System (INIS)

    Mahapatra, S.K.; Dhole, S.D.; Bhoraskar, V.N.

    2005-01-01

    An electron gun consisting of cathode, focusing electrode, control electrode and anode has been designed and fabricated for the electron irradiation experiments. This electron gun can provide electrons of any energy over the range 1-20 keV, with current upto 50 μA. This electron gun and a Faraday cup are mounted in the cylindrical chamber. The samples are fixed on the Faraday cup and irradiated with electrons at a pressure ∼10 -7 mbar. The special features of this electron gun system are that, at any electron energy above 1 keV, the electron beam diameter can be varied from 5 to 120 mm on the Faraday cup mounted at a distance of 200 mm from the anode in the chamber. The variation in the electron current over the beam spot of 120 mm diameter is less than 15% and the beam current stability is better than 5%. This system is being used for studying the irradiation effects of 1-20 keV energy electrons on the space quality materials in which the irradiation time may vary from a few tens of seconds to hours

  7. A 20 keV electron gun system for the electron irradiation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Mahapatra, S.K. [Department of Physics, University of Pune, Pune 411007 (India); Dhole, S.D. [Department of Physics, University of Pune, Pune 411007 (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 411007 (India)]. E-mail: vnb@physics.unipune.ernet.in

    2005-01-01

    An electron gun consisting of cathode, focusing electrode, control electrode and anode has been designed and fabricated for the electron irradiation experiments. This electron gun can provide electrons of any energy over the range 1-20 keV, with current upto 50 {mu}A. This electron gun and a Faraday cup are mounted in the cylindrical chamber. The samples are fixed on the Faraday cup and irradiated with electrons at a pressure {approx}10{sup -7} mbar. The special features of this electron gun system are that, at any electron energy above 1 keV, the electron beam diameter can be varied from 5 to 120 mm on the Faraday cup mounted at a distance of 200 mm from the anode in the chamber. The variation in the electron current over the beam spot of 120 mm diameter is less than 15% and the beam current stability is better than 5%. This system is being used for studying the irradiation effects of 1-20 keV energy electrons on the space quality materials in which the irradiation time may vary from a few tens of seconds to hours.

  8. Amorphization kinetics of Zr3Fe under electron irradiation

    International Nuclear Information System (INIS)

    Motta, A.T.; Howe, L.M.; Okamoto, P.R.

    1994-11-01

    Previous investigations using 40 Ar ion bombardments have revealed that Zr 3 Fe, which has an orthorhombic crystal structure, undergoes an irradiation-induced transformation from the crystalline to the amorphous state. In the present investigation, 0.9 MeV electron irradiations were performed at 28 - 220 K in a high-voltage electron microscope (HVEM). By measuring the onset, spread and final size of the amorphous region, factoring in the Gaussian distribution of the beam, a kinetic description of the amorphization in terms of dose, dose rate and temperature was obtained. The critical temperature for amorphization by electron irradiation was found to be ∼ 220 K, compared with 570 - 625 K for 40 Ar ion irradiation. Also, the dose-to-amorphization increased exponentially with temperature. Results indicated that the rate of growth of the amorphous region under the electron beam decreased with increasing temperature and the dose-to-amorphization decreased with increasing dose rate. The size of the amorphous region saturated after a given dose, the final size decreasing with increasing temperature, and it is argued that this is related to the existence of a critical dose rate, which increases with temperature, and below which no amorphization occurs. (author). 26 refs., 6 figs

  9. Amorphization kinetics of Zr3Fe under electron irradiation

    International Nuclear Information System (INIS)

    Motta, A.T.; Howe, L.M.; Okamoto, P.R.

    1992-10-01

    0.9 MeV electron irradiations were performed at 28--220 K in a high-voltage electron microscope (HVEM). By measuring onset, spread and final size of the amorphous region, factoring in the Guassian distribution of the beam, a kinetic description of the amorphization in terms of dose, dose rate and temperature was obtained. The critical temperature for amorphization by electron irradiation was found to be ∼220 K, compared to 570--625 K for 40 Ar ion irradiation. Also, the dose-to-amorphization increased exponentially with temperature. Results indicated that the rate of growth of the amorphous region under the electron beam decreased with increasing temperature and the does-to-amorphization decreased with increasing dose rate. The size of the amorphous region saturated after a region dose, the final size decreasing with increasing temperature, and it was argued that this is related to the existence of a critical dose rate, which increased with temperature, below which no amorphization occurred. The above observations can be understood in the framework of the kinetics of damage accumulation under irradiation

  10. Electron spin resonance investigations on polycarbonate irradiated with U ions

    Energy Technology Data Exchange (ETDEWEB)

    Chipara, M.I.; Reyes-Romero, J

    2001-12-01

    Electron spin resonance investigations on polycarbonate irradiated with uranium ions are reported. The dependence of the resonance line parameters (line intensity, line width, double integral) on penetration depth and dose is studied. The nature of free radicals induced in polycarbonate by the incident ions is discussed in relation with the track structure. The presence of severe exchange interactions among free radicals is noticed.

  11. Electron beam irradiation facility for low to high dose irradiation applications

    International Nuclear Information System (INIS)

    Petwal, V.C.; Wanmode, Yashwant; Verma, Vijay Pal; Bhisikar, Abhay; Dwivedi, Jishnu; Shrivastava, P.; Gupta, P.D.

    2013-01-01

    Electron beam based irradiation facilities are becoming more and more popular over the conventional irradiator facilities due to many inherent advantages such as tunability of beam energy, availability of radiation both in electron mode and X-ray mode, wide range of the dose rate, control of radiation from a ON-OFF switch and other safety related merits. A prototype experimental facility based on electron accelerator has been set-up at RRCAT to meet the low-dose, medium dose and high-dose requirements for radiation processing of food, agricultural and medical products. The facility can be operated in the energy range from 7-10 MeV at variable power level from 0.05-3 kW to meet the dose rate requirement of 100 Gy to kGy. The facility is also equipped with a Bremsstrahlung converter optimized for X-ray irradiation at 7.5 MV. Availability of dose delivery in wide range with precision control and measurement has made the facility an excellent tool for researchers interested in electron/X-ray beam irradiation. A precision dosimetry lab based on alanine EPR and radiochromic film dosimetry system have been established to characterize the radiation field and precise dose measurements. Electron beam scattering technique has been developed to achieve low dose requirement for EB irradiation of various seeds such as groundnut, wheat, soybeans, moong beans, black gram etc. for mutation related studies. This paper describes various features of the facility together with the dosimetric measurements carried out for qualification of the facility and recent irradiation experiments carried out using this facility. (author)

  12. Immunological aspect of the electron-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, K [Hyogo College of Medicine, Nishinomiya (Japan)

    1978-05-01

    In the present study, sciatic nerve tissues of the cat were emulsified with the complete Freund's adjuvant and injected into the foot-pads of the guinea pig. Frozen and frozen-irradiated feline sciatic nerve tissues were treated in the similar manner, and their encephalitogenicity was comparatively studied. Affected animals became skinny, weak in the hind limbs and sometimes solid their tails. Antigenic mixtures of the fresh peripheral nerves with adjuvant have sensitized 75% (15 out of 20) of guinea pigs, whereas none of the 41 animals manifested any sign of experimental allergic neuritis (EAN) after intradermal Frozen-preserved peripheral nerve-adjuvant mixtures gave rise to EAN in 29% (6 out of 21) of guinea pigs. The present results appear to show that the electron-beam irradiation might have modified the specific chemical structures of the myelin basic protein to completely suppress the encephalitogenicity of the peripheral nerve-tissues. High-voltage cathode irradiations would be capable of depressing the antigenicity of the transplantation immunology when the antigenic determinants have the chemical structures in common with the encephalitogenic antigens. Excessive amount of the irradiation used to result in severe tissue damages, therefore, an optimum dosis of electron-beams should be determined for each tissue destined for grafting. As the frozen peripheral nerve-adjuvant mixtures have been less encephalitogenic, freezing alone might well be considered partially to improve the acceptability of the grafts. Cryopreservation of the irradiated allografts would be worth further studying.

  13. Immunological aspect of the electron-beam irradiation

    International Nuclear Information System (INIS)

    Ikeda, Kimiyuki

    1978-01-01

    In the present study, sciatic nerve tissues of the cat were emulsified with the complete Freund's adjuvant and injected into the foot-pads of the guinea pig. Frozen and frozen-irradiated feline sciatic nerve tissues were treated in the similar manner, and their encephalitogenicity was comparatively studied. Affected animals became skinny, weak in the hind limbs and sometimes solid their tails. Antigenic mixtures of the fresh peripheral nerves with adjuvant have sensitized 75% (15 out of 20) of guinea pigs, whereas none of the 41 animals manifested any sign of experimental allergic neuritis (EAN) after intradermal Frozen-preserved peripheral nerve-adjuvant mixtures gave rise to EAN in 29% (6 out of 21) of guinea pigs. The present results appear to show that the electron-beam irradiation might have modified the specific chemical structures of the myelin basic protein to completely suppress the encephalitogenicity of the peripheral nerve-tissues. High-voltage cathode irradiations would be capable of depressing the antigenicity of the transplantation immunology when the antigenic determinants have the chemical structures in common with the encephalitogenic antigens. Excessive amount of the irradiation used to result in severe tissue damages, therefore, an optimum dosis of electron-beams should be determined for each tissue destined for grafting. As the frozen peripheral nerve-adjuvant mixtures have been less encephalitogenic, freezing alone might well be considered partially to improve the acceptability of the grafts. Cryopreservation of the irradiated allografts would be worth further studying. (author)

  14. Improvement in properties of plastic teeth by electron beam irradiation

    International Nuclear Information System (INIS)

    Sano, Yuko; Ishikawa, Shun-ichi; Seguchi, Tadao

    2011-01-01

    Improvement of the comfort and esthetics of artificial plastic teeth is desirable for the recently increasing numbers of elderly in society. Plastic teeth made of polycarbonate (PC) were modified by electron beam (EB) irradiation under specific conditions, and the change in the chemical properties of the PC was investigated. The water absorption, glucose attachment, level of bis-phenol-A (BPA) extraction, maltose adhesion, and mucin adhesion on the PC teeth were measured before and after EB irradiation. EB irradiation to a dose of 3.5 kGy at 150 o C in a nitrogen gas atmosphere reduced the water absorption by 20%, glucose absorption by 40%, maltose adhesion by 20%, and the amount of various amino acids, formed as the hydrolysis products of mucin, adhering on the PC teeth were reduced by 60-99%. The BPA content was lower than the detection limit for analysis of both the original and the EB irradiated PC teeth. - Highlights: → Radiation improvement of polycarbonate for plastic teeth by EB irradiation 3.5 kGy at 150 o C in inert gas. → Water and glucose absorption and maltose adhesion on PC teeth were much reduced. → Bis-phenol-A content from PC teeth was lower than the detection limit after irradiation.

  15. Positron lifetime measurements on electron irradiated amorphous alloys

    International Nuclear Information System (INIS)

    Moser, P.; Hautojaervi, P.; Chamberod, A.; Yli-Kauppila, J.; Van Zurk, R.

    1981-08-01

    Great advance in understanding the nature of point defects in crystalline metals has been achieved by employing positron annihilation technique. Positrons detect vacancy-type defects and the lifetime value of trapped positrons gives information on the size of submicroscopic vacancy aglomerates and microvoids. In this paper it is shown that low-temperature electron irradiations can result in a considerable increase in the positron lifetimes in various amorphous alloys because of the formation of vacancy-like defects which, in addition of the pre-existing holes, are able to trap positrons. Studied amorphous alloys were Fe 80 B 20 , Pd 80 Si 20 , Cu 50 Ti 50 , and Fe 40 Ni 40 P 14 B 6 . Electron irradiations were performed with 3 MeV electrons at 20 K to doses around 10 19 e - /cm 2 . After annealing positron lifetime spectra were measured at 77 K

  16. Investigation of the effect of some irradiation parameters on the response of various types of dosimeters to electron irradiation

    International Nuclear Information System (INIS)

    Farah, K.; Kuntz, F.; Kadri, O.; Ghedira, L.

    2004-01-01

    Several undyed and dyed polymer films are commercially available for dosimetry in intense radiation fields, especially for radiation processing of food and sterilisation of medical devices. The effects of temperature during irradiation and post-irradiation stability, on the response of these dosimeters are of importance to operators of irradiation facilities. The present study investigates the effects of temperature during irradiation by 2.2 MeV electrons beam accelerator and post irradiation storage on the response of several types of dosimeter films. All dosimeters showed a significant effect of temperature during irradiation and post-irradiation storage

  17. Investigation of the effect of some irradiation parameters on the response of various types of dosimeters to electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Farah, K. E-mail: k.farah@cnstn.rnrt.tn; Kuntz, F.; Kadri, O.; Ghedira, L

    2004-10-01

    Several undyed and dyed polymer films are commercially available for dosimetry in intense radiation fields, especially for radiation processing of food and sterilisation of medical devices. The effects of temperature during irradiation and post-irradiation stability, on the response of these dosimeters are of importance to operators of irradiation facilities. The present study investigates the effects of temperature during irradiation by 2.2 MeV electrons beam accelerator and post irradiation storage on the response of several types of dosimeter films. All dosimeters showed a significant effect of temperature during irradiation and post-irradiation storage.

  18. Comparison of initial damage rates using neutron and electron irradiations

    International Nuclear Information System (INIS)

    Goldstone, J.A.R.

    1978-08-01

    The purpose of this experiment was twofold: (1) The number of interstitials that pin dislocations was studied as a function of neutron energy. (2) By comparison with electron irradiations on the sample, a correlation between the predicted and measured numbers of defects was found. All irradiations were performed on the same high purity copper sample. The sample was machined in the form of a cantilever beam with a flexural resonant frequency of 770 Hz. Changes in Young's modulus at constant strain amplitude were monitored continuously through changes in the resonant frequency of the sample. These changes in the modulus can be related to the number of pinning points added to dislocation lines, which are in turn related to the number of free interstitials produced. Neutron energy dependence experiments were done from 2 to 24 MeV on the copper sample and at 14 MeV on a gold sample. By equating pinning rates from electron and neutron irradiations and using the free interstitial production rate obtained from electron irradiations, an estimate of the free interstitial production cross section for neutrons of 2 to 24 MeV was made

  19. Development of an irradiation device for electron beam wastewater treatment

    International Nuclear Information System (INIS)

    Rela, Paulo Roberto

    2003-01-01

    When domestic or industrial effluents with synthetic compounds are disposed without an adequate treatment, they impact negatively the environment with damages to aquatic life and for the human being. Both population and use of goods and services that contribute for the hazardous waste are growing. Hazardous regulations are becoming more restrictive and technologies, which do not destroy these products, are becoming less acceptable. The electron beam radiation process is an advanced oxidation process, that produces highly reactive radicals resulting in mineralization of the contaminant. In this work was developed an irradiation system in order to optimize the interaction of electron beam delivered from the accelerator with the processed effluent. It is composed by an irradiation device where the effluent presents to the electron beam in an up flow stream and a process control unit that uses the calorimetric principle. The developed irradiation device has a different configuration from the devices used by others researchers that are working with this technology. It was studied the technical and economic feasibility, comparing with the literature the results of the irradiation device demonstrated that it has a superior performance, becoming an process for use in disinfection and degradation of hazardous organic compounds of wastewater from domestic and industrial origin, contributing as an alternative technology for Sanitary Engineering. (author)

  20. Response of zircon to electron and Ne+ irradiation

    International Nuclear Information System (INIS)

    Devanathan, R.; Weber, W.J.; Boatner, L.A.

    1997-01-01

    Zircon (ZrSiO 4 ) is an actinide host phase in vitreous ceramic nuclear waste forms and a potential host phase for the disposition of excess weapons plutonium. In the present work, the effects of 800 and 900 keV electron and 1 MeV Ne + irradiations on the structure of single crystals of ZrSiO 4 have been investigated. The microstructural evolution during the irradiations was studied in situ using a high-voltage electron microscope interfaced to an ion accelerator at Argonne National Laboratory. The results indicate that electron irradiation at 15 K cannot amorphize ZrSiO 4 even at fluences an order of magnitude higher than that required for amorphization by 1.5 MeV Kr + ions. However, the material is readily amorphized by 1 MeV Ne + irradiation at 15 K. The temperature dependence of this amorphization is discussed in light of previous studies of radiation damage in ZrSiO 4

  1. Radiation safety of gamma and electron irradiation facilities

    International Nuclear Information System (INIS)

    1992-01-01

    There are currently some 160 gamma irradiation facilities and over 600 electron beam facilities in operation throughout virtually all Member States of the IAEA. The most widespread uses of these facilities are for the sterilization of medical and pharmaceutical products, the preservation of foodstuffs, polymer synthesis and modification, and the eradication of insect infestation. The safety record of this industry has been very good. Nevertheless, there is a potential for accidents with serious consequences. Gamma and electron beam facilities produce very high dose rates during irradiation, so that a person accidentally present in the irradiation chamber can receive a lethal dose within minutes or seconds. Precautions against uncontrolled entry must therefore be taken. Furthermore, gamma irradiation facilities contain large amounts of radioactivity and if the mechanism for retracting the source is damaged, the source may remain exposed, inhibiting direct access to carry out remedial work. Contamination can result from corroded or damaged sources, and decontamination can be very expensive. These aspects clearly indicate the need to achieve a high degree of safety and reliability in the facilities. This can be accomplished by effective quality control together with careful design, manufacture, installation, operation and decommissioning. The guidance in this Safety Series publication is intended for competent authorities responsible for regulating the use of radiation sources as well as the manufacturers, suppliers, installers and users of gamma and electron beam facilities. 20 refs, 6 figs

  2. Effect of ammonia and electron beam irradiation on lignocelulosic materials

    International Nuclear Information System (INIS)

    Mastro, N.L. del; Gennari, S.M.; Castagnet, A.C.G.

    1986-01-01

    Reports on some of the effects produced on sugarcane bagasse and eucaliptus wood saccharification by combining irradiation and NH 3 treatment. The samples irradiated at 10 5 Gy, 2x10 5 Gy and 5x10 5 Gy with an electron accelerator were treated with anhydrous gaseous ammonia. Cellulase complex from T. reesei was used for hydrolysis assays. Bromatological analysis and 'in vitro' digestibility tests were performed. The combination of EBI and ammonia treatments produced and increase in the saccharification yield, 'in vitro' digestibility and protein content for the two kinds of sample. (Author) [pt

  3. Segregation of a copper-nickel alloy after electron irradiation

    International Nuclear Information System (INIS)

    Wagner, W.

    1979-09-01

    In the present work measurement of diffuse neutron scattering are used to determine short range segregation effects of the alloy Cu 0 sub(.) 414 Ni 0 sub(.) 586 after thermal annealing and 3 MeV electron irradiation in the temperature range between 370 K and 600 K. In addition neutron small angle scattering measurement are performed after irradiation to study possible long range segregation effects. Residual resistivity measurements are performed in parallel in order tp orientate the relatively expensive neutron scattering measurements with respect to the residual changes (orig./KBI) [de

  4. The application analysis of high energy electron accelerator in food irradiation processing

    International Nuclear Information System (INIS)

    Deng Wenmin; Chen Hao; Feng Lei; Zhang Yaqun; Chen Xun; Li Wenjun; Xiang Chengfen; Pei Ying; Wang Zhidong

    2012-01-01

    Irradiation technology of high energy electron accelerator has been highly concerned in food processing industry with its fast development, especially in the field of food irradiation processing. In this paper, equipment and research situation of high energy electron accelerator were collected, meanwhile, the similarities and differences between high energy electron beam and 60 Co γ-rays were discussed. In order to provide more references of high energy electron beam irradiation, the usages of high energy electron in food irradiation processing was prospected. These information would promote the development of domestic food irradiation industry and give a useful message to irradiation enterprises and researchers. (authors)

  5. Electron microbeam specifications for use in cell irradiation experiments

    International Nuclear Information System (INIS)

    Kim, E.-H.; Choi, M.-C.; Lee, D.-H.; Chang, M.; Kang, C.-S.

    2003-01-01

    The microbeam irradiation system was devised originally to identify the hit and unhit cells by confining the beam within the target cell. The major achievement through the microbeam experiment studies has turned out to be the discovery of the 'bystander effect'. Microbeam experiments have been performed with alpha and proton beams in major and with soft x-rays in minor. The study with electron microbeam has been deferred mainly due to the difficulty in confining the electron tracks within a single target cell. In this paper, the electron microbeam irradiation system under development in Korea is introduced in terms of the beam specifications. The KIRAMS electron microbeam irradiation system consists of an electron gun, a vacuum chamber for beam collimation into 5 μm in diameter and a biology stage. The beam characteristics in terms of current and energy spectrum of the electrons entering a target cell and its neighbor cells were investigated by Monte Carlo simulation for the electron source energies of 25, 50, 75 and 100 keV. Energy depositions in the target cell and the neighbor cells were also calculated. The beam attenuation in current and energy occurs while electrons pass through the 2 μm-thick Mylar vacuum window, 100 μm-thick air gap and the 2 μm-thick Mylar bottom of cell dish. With 25 keV electron source, 80 % of decrease in current and 30 % of decrease in average energy were estimated before entering the target cell. With 75 keV electron source, on the other hand, 55 % of decrease in current and less than 1 % of decrease in average energy were estimated. Average dose per single collimated electron emission was 0.067 cGy to the target cell nucleus of 5 μm in diameter and 0.030 cGy to the cytoplasm of 2.5 μm in thickness with 25 keV electron source while they were 0.15 cGy and 0.019 cGy, respectively, with 75 keV electron source. The multiple scattering of electrons resulted in energy deposition in the neighbor cells as well. Dose to the first

  6. Plastic coating on paper by electron beam irradiation

    International Nuclear Information System (INIS)

    Ametani, Kazuo; Tsuchiya, Mitsuaki; Sawai, Takeshi

    1984-01-01

    It has been known long since that the resin system of unsaturated polyester and vinylmonomer mixture cures by irradiation. Ford of USA for the first time industrialized the radiation curing reaction of resins for the coating of automobile parts. Thereafter, accompanying the development and technical advance of the low energy electron beam irradiation apparatus which is suitable to surface treatment such as coating and easy to handle and the development of resins, the electron beam curing method has become to be utilized for coating hardboard and wooden doors, coating automobile tire rims, adhering printing papers and others. The electron beam curing method has advantage such as energy conservation, resource saving and little pollution because solvent is not used, high production rate and small floor space. In glossing industry, for the purpose of developing the techniques to apply electron beam curing method to glazed paper production, the selection of the composition of resins suitable to glazed papers, the irradiating condition and the properties of cured films were examined. The films withstanding bending can be obtained at low dose with urethane group, ester group or the combination of monomers. (Kako, I.)

  7. Quantitative analysis of complexes in electron irradiated CZ silicon

    International Nuclear Information System (INIS)

    Inoue, N.; Ohyama, H.; Goto, Y.; Sugiyama, T.

    2007-01-01

    Complexes in helium or electron irradiated silicon are quantitatively analyzed by highly sensitive and accurate infrared (IR) absorption spectroscopy. Carbon concentration (1x10 15 -1x10 17 cm -3 ) and helium dose (5x10 12 -5x10 13 cm -2 ) or electron dose (1x10 15 -1x10 17 cm -2 ) are changed by two orders of magnitude in relatively low regime compared to the previous works. It is demonstrated that the carbon-related complex in low carbon concentration silicon of commercial grade with low electron dose can be detected clearly. Concentration of these complexes is estimated. It is clarified that the complex configuration and thermal behavior in low carbon and low dose samples is simple and almost confined within the individual complex family compared to those in high concentration and high dose samples. Well-established complex behavior in electron-irradiated sample is compared to that in He-irradiated samples, obtained by deep level transient spectroscopy (DLTS) or cathodoluminescence (CL), which had close relation to the Si power device performance

  8. Radiation defects in electron-irradiated InP crystals

    Energy Technology Data Exchange (ETDEWEB)

    Brailovskii, E.Yu.; Karapetyan, F.K.; Megela, I.G.; Tartachnik, V.P. (AN Ukrainskoj SSR, Kiev. Inst. Yadernykh Issledovanij)

    1982-06-16

    The results are presented of formation and annealing of defects in InP crystals at 1 to 50 MeV electron irradiation. The recovery of electrical properties in the range of 77 to 970 K during annealing processes is studied. Five low temperature annealing states in n-InP and the reverse annealing in p-InP are observed at 77 to 300 K. Four annealing stages at temperatures higher than 300 K are present. When the electron energy is increased more complicated thermostable defects are formed, and at 50 MeV electron energy besides of the point defect clusters are formed, which anneal at temperatures of 800 to 970 K. It is shown that the peculiarities of the Hall mobility at irradiation and annealing are caused by the scattering centres E/sub c/ - 0.2 eV. The 'limiting' position of the Fermi level in electron irradiated InP crystals is discussed.

  9. A structure development in electron-irradiated type Ia diamond

    International Nuclear Information System (INIS)

    Novikov, N.V.; Ositinskaya, T.D.; Tkach, V.N.

    1998-01-01

    A type Ia diamond crystal with nitrogen impurity in different forms was irradiated by 3.5 MeV electrons with increasing doses 5 centre dot 10 16 , 2 centre dot 10 17 , 4 centre dot 10 17 , 2 centre dot 10 18 e/cm 2 and investigated before and after each dose by positron annihilation, EPR, and optical spectroscopy. After irradiation with the highest dose, the effect of development of a visible defective structure of the crystal is revealed. A description of this effect and data of EPR and IR-measurements depending on irradiation doses are presented. First results of cathodoluminescence (CL) studies in the form CL-topograms and CL-spectra for difference zones of the crystal are also given

  10. Improvement of carbon fiber surface properties using electron beam irradiation

    International Nuclear Information System (INIS)

    Pino, E.S.; Machado, L.D.B.; Giovedi, C.

    2007-01-01

    Carbon fiber-reinforced advance composites have been used for structural applications, mainly on account of their mechanical properties. The main factor for a good mechanical performance of carbon fiber-reinforced composite is the interfacial interaction between its components, which are carbon fiber and polymeric matrix. The aim of this study is to improve the surface properties of the carbon fiber using ionizing radiation from an electron beam to obtain better adhesion properties in the resultant composite. EB radiation was applied on the carbon fiber itself before preparing test specimens for the mechanical tests. Experimental results showed that EB irradiation improved the tensile strength of carbon fiber samples. The maximum value in tensile strength was reached using doses of about 250 kGy. After breakage, the morphology aspect of the tensile specimens prepared with irradiated and non-irradiated car- bon fibers were evaluated. SEM micrographs showed modifications on the carbon fiber surface. (authors)

  11. Tailoring crystallinity and configuration of silica nanotubes by electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, Tomitsugu, E-mail: taguchi.tomitsugu@jaea.go.jp; Yamaguchi, Kenji

    2015-05-01

    Highlights: •Single-crystal SiO{sub 2} nanotubes were successfully synthesized for the first time. •The single-crystal SiO{sub 2} was α-crystobalite. •Desired area of single-crystal nanotube can be changed to amorphous by electron irradiation. •The configuration of nanotube can be controlled using the focused electron irradiation technique. -- Abstract: SiO{sub 2} nanotubes show potential in applications such as nanoscale electronic and optical devices, bioseparation, biocatalysis, and nanomedicine. As-grown SiO{sub 2} nanotubes in the previous studies always have an amorphous wall, and here we demonstrate the successful synthesis of single-crystal nanotubes for the first time by the heat treatment of SiC nanotubes at 1300 °C for 10 h under low-vacuum conditions. According to TEM observations, the single-crystal SiO{sub 2} was α-cristobalite. We also demonstrate that single-crystal SiO{sub 2} nanotubes can be transformed into amorphous SiO{sub 2} nanotubes by electron beam irradiation. Moreover, we synthesized a crystalline/amorphous SiO{sub 2} composite nanotube, in which crystalline and amorphous SiO{sub 2} coexisted in different localized regions. In addition, for biomedical applications such as drug delivery systems, controlling the configuration of the open end, the diameter, and capsulation of SiO{sub 2} nanotubes is crucial. We can also obturate, capsulate, and cut a SiO{sub 2} nanotube, as well as modify the inner diameter of the nanotube at a specific, nanometer-sized region using the focused electron beam irradiation technique.

  12. Defect creation rates in CdTe irradiated by electrons

    International Nuclear Information System (INIS)

    Caillot, M.

    1978-01-01

    Up to now, the defect creation rates in CdTe irradiated by electrons were unknown. They have been calculated for different electron kinetic energies. As the samples studied are thick, the energy loss when the electrons penetrate the material has been taken into account. The cross-sections of Cd and Te displacements vs the depth of electron penetration were determined for different electron kinetic energies, and the defect creation rates obtained for each sublattice. These creation rates have been compared with those deduced from experiments and it was found that the experimental creation rates were lower than the calculated ones. This discrepancy can be explained in terms of creation of neutral Frenkel pairs. (Auth.)

  13. Irradiation of aluminium alloy materials with electron beam

    International Nuclear Information System (INIS)

    Konno, Osamu; Masumoto, Kazuyoshi

    1982-01-01

    It is a theme with a room for discussion to employ the stainless steel composed of longer half-life materials for the vacuum system of accelerators, from the viewpoint of radiation exposure. Therefore, it is desirable to use aluminium of shorter half-life in place of stainless steel. As a result of investigation on the above theme in the 1.2 GeV electron linac project in Tohoku University, it has been concluded that aluminium alloy vacuum chambers can reduce exposure dose by about one or two figures as compared with stainless steel ones. Of course, aluminium alloy contains trace amounts of Mg, Si, Ti, Cr, Mn, Fe, Zn, Cu and others. Therefore, four kinds of aluminium alloy considered to be usable have been examined for induced radioactivity by electron beam irradiation. Stainless steel SUS 304 has been also irradiated for comparison. Radiation energy has been 30 MeV and 200 MeV. When stainless steel and aluminium alloy were compared, aluminium alloy was very effective for reducing surface dose in low energy irradiation. In 200 MeV irradiation, the dose ratio of aluminium alloy to stainless steel became 1/30 to 1/100 after one week, though the dose difference between these two materials became smaller in 100 days or more after irradiation. If practical inspection and repair are implemented during the period from a few days to one week after shutdown, the aluminium alloy is preferable for exposure dose reduction even in high energy irradiation. (Wakatsuki, Y.)

  14. Electron beam irradiation effects on carbon fiber reinforced PEEK composite

    International Nuclear Information System (INIS)

    Sasuga, Tsuneo; Hagiwara, Miyuki; Odajima, Tosikazu; Sakai, Hideo; Nakakura, Toshiyuki; Masutani, Masahiro.

    1987-03-01

    Carbon fiber(CF) reinforced composites, using polyarylether-sulfone (PES) or polyarylether-ether-ketone (PEEK) as matrix material, were prepared and their electron beam irradiation effects were studied on the basis of changes in mechanical and dynamic viscoelastic properties and observation of fracture surfaces. The flexural strength of PES-CF composite decreased to 70 % of the initial strength after the irradiation of 3 MGy and 40 % after 15 MGy. The change in the profile of stress-strain (S-S) curves and fractographic observation by electron microscopy indicated that this composite irradiated with over 3 MGy was fractured by delamination caused by to the degradation of matrix polymer. The mechanical properties of PEEK-CF composite were scarcely decreased even after irradiated up to 180 MGy and this composite showed very high radiation resistance. The change in the profile of S-S curves and fractographic observation showed that this composite fractured due to destruction of fiber in the dose range less than 180 MGy, indicating that PEEK was excellent matrix material used in high radiation field. PEEK-PES-CF composite which was composed of the carbon fibers coated with PES solution showed less radiation resistance compared with PEEK-CF composite; the flexural strength decreased to 85 % of the initial value after the irradiation with 90 MGy. It was revealed from the changes in the profile of S-S curve that the specimen irradiated over 120 MGy was fractured due to not only fiber destruction but delamination. Deterioration mechanism of PEEK-PES-CF composite was studied by dynamic viscoelastic measurements in connection with the damage on matrix-fiber interface. It was suggested that the deterioration in mechanical properties of this composite was caused by the degradation of PES that coated on the surface of the carbon fibers. (author)

  15. A permanent magnet electron beam spread system used for a low energy electron irradiation accelerator

    International Nuclear Information System (INIS)

    Huang Jiang; Xiong Yongqian; Chen Dezhi; Liu Kaifeng; Yang Jun; Li Dong; Yu Tiaoqin; Fan Mingwu; Yang Bo

    2014-01-01

    The development of irradiation processing industry brings about various types of irradiation objects and expands the irradiation requirements for better uniformity and larger areas. This paper proposes an innovative design of a permanent magnet electron beam spread system. By clarifying its operation principles, the author verifies the feasibility of its application in irradiation accelerators for industrial use with the examples of its application in electron accelerators with energy ranging from 300 keV to 1 MeV. Based on the finite element analyses of electromagnetic fields and the charged particle dynamics, the author also conducts a simulation of electron dynamics in magnetic field on a computer. The results indicate that compared with the traditional electron beam scanning system, this system boosts the advantages of a larger spread area, non-power supply, simple structure and low cost, etc., which means it is not only suitable for the irradiation of objects with the shape of tubes, strips and panels, but can also achieve a desirable irradiation performance on irregular constructed objects of large size. (authors)

  16. Allergies, asthma, and pollen

    Science.gov (United States)

    Reactive airway - pollen; Bronchial asthma - pollen; Triggers - pollen; Allergic rhinitis - pollen ... Things that make allergies or asthma worse are called triggers. It is important to know your triggers because avoiding them is your first step toward feeling better. ...

  17. Detection of electron beam irradiated crude drugs by electron spin resonance (ESR)

    International Nuclear Information System (INIS)

    Yamaoki, Rumi; Kimura, Shojiro; Aoki, Kenji; Nishimoto, Susumu

    2007-01-01

    Perillae Herba, Sennae Folium, Cinnamomi Cortex, Phellodendri Cortex, Ginseng Radix, Glycyrrhizae Radix, Paeoniae Radix, and Zingiberis Rhizoma were irradiated with electron beam (5 MeV) and organic radicals were detected by ESR measurement, before and after irradiation (10 kGy). A single line spectrum was detected at around g=2.005 in non-irradiated crude drugs, and radical concentrations were high in the leaf varieties of crude drugs. After irradiation, the signal intensity around g=2.005 increased, and a new subsignal was detected as a 3 mT shoulder of this signal. Broad, asymmetrically divided signals were also detected in irradiated root varieties of crude drugs. The free radical localized on the organic components of irradiated crude drugs tended to decrease with the water content. After irradiation, signal intensity reduced and reached a steady state after about 1 to 2 months. However, specificity of the ESR signal shape appearing after irradiation continued to be detectable for 6 months in leaf varieties and for a year in bark and root varieties of crude drugs. Consequently, it was concluded that ESR could be applied as an initial screening procedure to detect irradiated crude drugs. (author)

  18. Color formation study of irradiated polymers by electron beam

    International Nuclear Information System (INIS)

    Nardi, Daniela Teves

    2004-01-01

    Color formation on national and commercial polymers (polymethyl methacrylate, polystyrene and polycarbonate) irradiated by electrons beam was investigated by colorimetry (CIELab), electron spectroscopy resonance (ESR), photoacoustic infrared spectroscopy (FTIR-PAS) and differential exploratory calorimetry (DSC). The heat effect on colorimetric properties was investigated after heating (110 deg C for 1 hour) of irradiated polymers at 150 kGy. The rule of oxygen in colorimetric properties of irradiated polycarbonate was investigated in the air presence and absence (p = 10 -3 mmHg). The visual aspect did not agree with colorimetric parameters only for polycarbonate. Yellow color and darkness were induced by radiation for all studied polymers varying only the intensity and behavior in function of post-irradiation time and heating. Polymethyl methacrylate and polystyrene ESR spectra showed that radicals could be responsible by yellow color centers. Wherever, in polycarbonate, color centers were not due radical species. The nature of color centers for any studied polymer was not study by FTIR-PAS because there were no changes in FTIR-PAS spectra neither in function of dose nor heating. Polycarbonate was the most radiosensible and polystyrene was the most radioresistant of all studied polymers in concern of colorimetric properties. (author)

  19. Improvement of carbon fibre surface properties using electron beam irradiation

    International Nuclear Information System (INIS)

    Eddy Segura Pino; Luci Diva Brocardo Machado; Claudia Giovedi

    2006-01-01

    Carbon fiber-reinforced advance composites have been used for structural applications, mainly due to their mechanical properties, and additional features such as high strength-to-weight ratio, stiffness-to-weight ratio, corrosion resistance and wear properties. The main factor for a good mechanical performance of carbon fiber-reinforced composite is the interfacial interaction between the components that are fiber and polymeric matrix. The greatest challenge is to improve adhesion between components having elasticity modulus which differ by orders of magnitude and furthermore they are immiscible in each other. Another important factor is the sizing material on the carbon fiber, which protects the carbon fiber filaments and must be compatible with the matrix material in order to improve the adhesion process. The interaction of ionizing radiation from electron beam can induce in the irradiated material the formation of very active centers and free radicals. Further evolution of these active species can significantly modify structure and properties not only in the irradiated polymeric matrix but also on the fiber surface. So that, fiber and matrix play an important role in the production of chemical bonds, which promote better adhesion between both materials improving the composite mechanical performance. The aim of this work was to improve the surface properties of the carbon fiber surface using ionizing radiation from an electron beam in order to obtain improvement of the adhesion properties in the resulted composite. Commercial carbon fiber roving of high tensile strength with 12 000 filaments named 12 k, and sizing material of epoxy resin modified by ester groups was studied. EB irradiation has been carried out at the Institute for Nuclear and Energy Research (IPEN) facilities using a 1.5 MeV 37.5 kW Dynamitron electron accelerator model JOB-188. Rovings of carbon fibers with 1.78 g cm -3 density and 0.13 mm thickness were irradiated with 0.555 MeV, 6.43 mA and

  20. Defects in low temperature electron irradiated InP

    International Nuclear Information System (INIS)

    Suski, J.; Bourgoin, J.

    1984-01-01

    n and p-InP has been irradiated at 25K with 1MeV electrons and the created defects were studied by deep level transient spectroscopy (DLTS) in the range 25K-400K. In n-InP, four traps are directly observed, with low introduction rates except for one. They anneal in three stages, and four new centers of still lower concentration appear after 70 0 C heat treatment. In p-InP, two dominant traps stable up to approx.= 400K with introduction rates close to the theoretical ones, which might be primary defects are found, while another one is clearly a secondary defect likely associated to Zn dopant. At least two of the low concentration irradiation induced electron traps, created between 25K and 100K are also secondary defects, which implies a mobility of some primary defects down to 100K at least. (author)

  1. Electron spin resonance of gamma, electron, neutron and fission fragments irradiated K2SO4

    International Nuclear Information System (INIS)

    Kamali, J.; Walton, G.N.

    1985-01-01

    The electron spin resonance (ESR) of K 2 SO 4 irradiated by γ, electron, neutron and fission fragments has been investigated. The ESR spectra are attributed mainly to the formation of SO 3 - , SO 4 - , SO 2 - , and O 3 - radical ions. The most intense radical ion observed was due to the SO 3 - , and the other radicals were relatively much lower in intensity. Thermal annealing showed a significant decrease in the concentration of radical ions. The concentration of SO 3 - was measured in γ-irradiated K 2 SO 4 and K 2 SO 4 containing fission fragments. In fission fragments irradiated K 2 SO 4 , the G-value observed for SO 3 - radical formation was about eight times higher than that of γ-irradiated K 2 SO 4 . This was attributed to the high LET (Linear Energy Transfer) of the fission fragments. (author)

  2. Bulk Cutting of Carbon Nanotubes Using Electron Beam Irradiation

    Science.gov (United States)

    Ziegler, Kirk J. (Inventor); Rauwald, Urs (Inventor); Hauge, Robert H. (Inventor); Schmidt, Howard K. (Inventor); Smalley, Richard E. (Inventor); Kittrell, W. Carter (Inventor); Gu, Zhenning (Inventor)

    2013-01-01

    According to some embodiments, the present invention provides a method for attaining short carbon nanotubes utilizing electron beam irradiation, for example, of a carbon nanotube sample. The sample may be pretreated, for example by oxonation. The pretreatment may introduce defects to the sidewalls of the nanotubes. The method is shown to produces nanotubes with a distribution of lengths, with the majority of lengths shorter than 100 tun. Further, the median length of the nanotubes is between about 20 nm and about 100 nm.

  3. Positron lifetime study of electron-irradiated epoxy resins

    International Nuclear Information System (INIS)

    Suevegh, K.; Vertes, A.; Wojnarovits, L.; Foeldiak, G.; Liszkai, L.; Kajcsos, Zs.

    1990-01-01

    Two bisphenol-A type epoxy resins were irradiated by electron beam and studied afterwards by positron lifetime spectroscopy. An interesting result is that despite of the considerable amount of free-radicals, no inhibition of positronium formation was observed in the two epoxies. Nevertheless, several serious differences were detected between the studied polymers. The results suggest that the radiation-resistant properties of epoxies depend strongly on the amount of the curing agent. (author) 8 refs.; 2 figs

  4. Thermoluminescence in KBr:D electron irradiated at room temperature

    International Nuclear Information System (INIS)

    Paredes Campoy, J.C.; Lopez Carranza, E.

    1991-07-01

    The thermoluminescence of KBr:D samples electron irradiated at room temperature after thermal annealing at 673 K for 1 hour have been studied in the temperature range 360-730 K. The experimental TL-curve was discomposed by computer analysis in seven overlapping TL peaks, giving for them the order of the kinetics of thermal stimulation, the activation energy, the frequency factor, the relative values of the electronic concentration in traps at the initial heating temperature and the temperature at the maximum of the peak. (author). 18 refs, 1 fig., 3 tabs

  5. Positron annihilation in hydrogenated and electron-irradiated titanium alloys

    International Nuclear Information System (INIS)

    Mukashev, K.M.; Zaikin, Yu.A.

    2002-01-01

    Important information on hydrogen behavior in titanium can be obtained from studies of radiation damage in previously hydrogenated metal. For this purpose annealed titanium samples were hydrogenated at the temperature 500 deg. C during 1 hour. Then both the original annealed samples and hydrogenated samples were irradiated by 4 MeV electrons in the fluence range 3·10 7 -1·10 19 cm - 2 at the temperature 60 deg. C. It is known that electron irradiation in these conditions predominantly creates vacancy-type defects with an average radius R ν =0.81 Angstrom. It was stated that annihilation probability after electron irradiation of previously hydrogenated titanium samples always has some intermediate values between those characteristic for hydrogenated and irradiated states of previously annealed metal. This is a reason to suppose that radiation defects of the vacancy type in previously hydrogenated titanium combine with hydrogen atoms in favorable conditions of their partial ionization. The estimated value of the average radius for such a complex is R ν =1.1 Angstrom, that is higher than vacancy size but lower than an atom radius. No dose dependence of hydrogen interaction with radiation defects was observed in our experiments.The results of isochrone annealing of the materials under study have shown that the single annealing recovery stage with activation energy E a equal to 1.22 eV is observed in electron irradiated but not previously hydrogenated titanium in the temperature range 170-240 deg. C. Electron irradiation of the previously hydrogenated metal shifts beginning of the first recovery stage to the temperature about 225-230 deg. C and finishes near the temperature 330 deg. C. Therefore, the bound state vacancy-hydrogen in titanium is characterized by higher temperature range of dissociation and annealing with activation energy equal to 1.38 eV. However, subsequent measurements, of the angular distribution of annihilation photons (ADAP) have demonstrated

  6. Dosimetry study for electron beam irradiation in radiation processing

    International Nuclear Information System (INIS)

    Sunaga, Hiromi; Haruyama, Yasuyuki; Takizawa, Haruki; Kojima, Takuji; Yotsumoto, Keiichi

    1995-01-01

    For certain critical applications such as medical device sterilization and food irradiation, accurate calibration of electron energy and absorbed dose is required to assure the quality of irradiated products. To meet this requirement, TRCRE, JAERI has carried out research and development on high dose radiation dosimetry for electron beams in the energy range used in radiation processing (0.15 - 3.0 MeV). JAERI has developed a simultaneous electron beam energy and dosimeter calibration system that consist of a total absorption calorimeter, an electron current density meter, and a stacked thin-film dosimeter set. For low energy electrons, where it is important to measure the depth-dose profile in materials with high depth resolution, we studied the feasibility of a method using Gafchromic film dosimeters. This film, which has an 8-μm thick sensitive layer, is combined with a stepped array of absorber films of the same thickness to produce a high-resolution depth-dose profile on the Gafchromic film. The depth-dose profile obtained in this manner has about five times greater resolution than conventional radiochromic film dosimetry. (author)

  7. Space-charge-limited currents in electron-irradiated dielectrics

    International Nuclear Information System (INIS)

    Nunes de Oliveira, L.; Gross, B.

    1975-01-01

    This paper develops the theory of steady-state currents generated in a dielectric placed between positively or negatively biased electrodes and irradiated with a partially penetrating electron beam. The dielectric is divided into an irradiated region (IR), which extends from the electrode of incidence to the extrapolated range of the beam, and a nonirradiated region (NIR). In the IR the primary beam generates an electron-hole plasma. Its end plane acts as a virtual electrode embedded in the dielectric. Currents are space-charge limited in the NIR and Ohmic in the IR which is characterized by a uniform radiation-induced conductivity. Depending on the polarity of the electrode bias, electrons or holes are drawn from the IR into the NIR. The theory correctly predicts an apparent threshold effect for the inset of steady-state currents: the current amplitudes remain small as long as the electron range is smaller than half the sample thickness, and increase strongly only afterwards. Calculated current curves for different beam energies are in satisfactory agreement with experimental results. The role of the electron beam as a virtual electrode is discussed

  8. Disinfection of wastewaters: high-energy electron vs gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Farooq, S [King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia). Dept. of Civil Engineering; Kurucz, C N; Waite, T D [Miami Univ., Coral Gables, FL (United States); Cooper, W J [Florida International Univ., Miami, FL (United States). Drinking Water Research Center

    1993-07-01

    A study was undertaken to examine the sensitivity of a wastewater population of coliphage, total coliforms and total flora present in raw sewage and secondary effluent after irradiating with similar doses delivered by a high-energy electron beam and [gamma]-radiation. The electron beam study was conducted on a large scale at the Virginia Key Wastewater Treatment Plant, Miami, Florida. The facility is equipped with a 1.5 MeV, 50 mA electron accelerator, with a wastewater flow rate of 8ls[sup -1]. Concurrent [gamma]-radiation studies were conducted at laboratory scale using a 5000 Ci, [sup 60]Co [gamma]-source. Three logs reduction of all three test organisms were observed at an electron beam dose of 500 krads, while at least four logs reduction were observed at the same dose utilizing the [gamma]'source. (Author).

  9. The effect of simultaneous electron and Kr+ irradiation on amorphization of CuTi

    International Nuclear Information System (INIS)

    Koike, J.; Okamoto, P.R.; Rehn, L.E.; Meshii, M.

    1989-01-01

    CuTi was irradiated with 1-MeV electrons and Kr + ions simultaneously at temperatures from 10 to 423 K. Retardation of Kr + -induced amorphization was observed with simultaneous electron irradiation at 295 and 423 K. The retardation effect increased with increasing irradiation temperature and relative electron-to-Kr dose rate. In contrast, simultaneous irradiation below 100 K showed an additive effect of electron- and Kr + -induced amorphization. The results can be explained by the mobility point defects introduced by electron irradiation interacting with Kr + -induced displacement cascades. 6 refs., 6 figs

  10. Vulcanization of rubber mixtures by simultaneous electron beam and microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Martin, D. E-mail: martin@ifin.nipne.ro; Ighigeanu, D.; Mateescu, E.; Craciun, G.; Ighigeanu, A

    2002-08-01

    The comparative results obtained by applying separate electron beam (EB) irradiation and simultaneous EB and microwave (MW) irradiation to vulcanization of rubber mixtures based on natural rubber and polybutadiene rubber with carbon black are presented. In the absence of MW, EB irradiation doses of 200-250 kGy are required in order to obtain a higher vulcanization degree. The irradiation doses as well as irradiation times were markedly diminished, from 2 to 6 times, by simultaneous EB and MW irradiation.

  11. Lifetime of Macroradicals in UHMWPE Irradiated with Electron Beam

    International Nuclear Information System (INIS)

    Costa, L.

    2006-01-01

    Interaction of high energy radiation with UHMWPE leads to the scission of C-C and C-H bonds both in the amorphous and in the criystalline phase, giving H radicals, macroradicals and trans vinylene double bonds. If oxygen is present, alkyl macroradicals react immediately with it and the oxidation chain process begins. In this case the main products are hydroperoxides. In our laboratory ultra high molecular weight polyethylene (medical grade GUR 1050) has been irradiated with electron beam in vacuum and in presence of oxygen at room temperature. Electron beam irradiation has been considered in order to neglect irradiation time, that is shorter (maximum 2 minutes) than gamma irradiation time and negligible compared to the following observation time. UHMWPE irradiated has been examined with two different techniques, FTIR and EPR spectroscopy. Micro FTIR Spectroscopy has been carried out on UHMWPE to evaluate hydroperoxide concentration in samples irradiated in presence of oxygen. Hydroperoxides and their distribution inside samples can be observed very well with FTIR microscopy after a derivatization process (with NO). The obtained hydroperoxide profile decreases when distance from the outer surface increases till it achieves a plateau. The first decrease can be attributed to macroradicals reaction with oxygen, that can diffuse only in the amorphous phase. Value obtained in the centre of block is correlated only with oxygen dissolved in UHMWPE before irradiation. If radicals live for some hours, oxygen can diffuse into UHMWPE during the macroradicals lifetime and the hydroperoxides profile is a curve similar to that obtained. Comparing the oxygen diffusion curve, calculated in the function of Fick's law, with the hydroperoxide profile, we have obtained a good agreement when oxygen diffusion is calculated over two hours. This means that the macroradicals must survive at least for two hours in the amorphous phase. EPR Spectroscopy was undertaken to explore the nature of

  12. Radiation doses inside industrial irradiation installation with linear electron accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Alexandre R., E-mail: alexandre.lima@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil); Pelegrineli, Samuel Q.; Alo, Gabriel F., E-mail: samuelfisica@yahoo.com.br, E-mail: gabriel.alo@aceletron.com.br [Aceletron Irradiacao Industrial, Aceletrica Comercio e Representacoes Ltda, Rio de Janeiro, RJ (Brazil); Silva, Francisco C.A. Da, E-mail: dasilva@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    Aceletron Industrial Irradiation Company is the unique installation in South America to provide industrial irradiation service using two linear electron accelerators of 18 kW and 10 MeV energy. The electron beam technology allows using electrons to irradiate many goods and materials, such as hospital and medical equipment, cosmetics, herbal products, polymers, peat, gemstones and food. Aceletron Company uses a concrete bunker with 3.66 m of thickness to provide the necessary occupational and environmental radiation protection of X-rays produced. The bunker is divided in main four areas: irradiation room, maze, tower and pit. Inside the irradiation room the x-rays radiation rates are measured in two ways: direct beam and 90 deg C. The rates produced in the conveyor system using 10 MeV energy are 500 Gy/min/mA and 15 Gy/min/mA, respectively. For a 1.8 mA current, the rates produced are 900 Gy/min and 27 Gy/min, respectively. Outside the bunker the radiation rate is at background level, but in the tower door and modulation room the radiation rate is 10 μSv/h. In 2014, during a routine operation, an effective dose of 30.90 mSv was recorded in a monthly individual dosimeter. After the investigation, it was concluded that the dose was only in the dosimeter because it felt inside the irradiation room. As Aceletron Company follows the principles of safety culture, it was decided to perform the radiation isodose curves, inside the four areas of the installation, to know exactly the hotspots positions, exposure times and radiation doses. Five hotspots were chosen taking into account worker's routes and possible operational places. The first experiment was done using a package with three TLD and OSLD dosimeters to obtain better statistical results. The first results for the five hotspots near the accelerator machine showed that the radiation dose rates were between 26 Gy/h and 31 Gy/h. The final measurements were performed using a package with one TLD and one OSLD

  13. Radiation doses inside industrial irradiation installation with linear electron accelerator

    International Nuclear Information System (INIS)

    Lima, Alexandre R.; Pelegrineli, Samuel Q.; Alo, Gabriel F.; Silva, Francisco C.A. Da

    2015-01-01

    Aceletron Industrial Irradiation Company is the unique installation in South America to provide industrial irradiation service using two linear electron accelerators of 18 kW and 10 MeV energy. The electron beam technology allows using electrons to irradiate many goods and materials, such as hospital and medical equipment, cosmetics, herbal products, polymers, peat, gemstones and food. Aceletron Company uses a concrete bunker with 3.66 m of thickness to provide the necessary occupational and environmental radiation protection of X-rays produced. The bunker is divided in main four areas: irradiation room, maze, tower and pit. Inside the irradiation room the x-rays radiation rates are measured in two ways: direct beam and 90 deg C. The rates produced in the conveyor system using 10 MeV energy are 500 Gy/min/mA and 15 Gy/min/mA, respectively. For a 1.8 mA current, the rates produced are 900 Gy/min and 27 Gy/min, respectively. Outside the bunker the radiation rate is at background level, but in the tower door and modulation room the radiation rate is 10 μSv/h. In 2014, during a routine operation, an effective dose of 30.90 mSv was recorded in a monthly individual dosimeter. After the investigation, it was concluded that the dose was only in the dosimeter because it felt inside the irradiation room. As Aceletron Company follows the principles of safety culture, it was decided to perform the radiation isodose curves, inside the four areas of the installation, to know exactly the hotspots positions, exposure times and radiation doses. Five hotspots were chosen taking into account worker's routes and possible operational places. The first experiment was done using a package with three TLD and OSLD dosimeters to obtain better statistical results. The first results for the five hotspots near the accelerator machine showed that the radiation dose rates were between 26 Gy/h and 31 Gy/h. The final measurements were performed using a package with one TLD and one OSLD

  14. Application of electron paramagnetic resonance to identify irradiated soybean

    International Nuclear Information System (INIS)

    Bhaskar, S.; Behere, Arun; Sharma, Arun

    2006-01-01

    Full text: Electron paramagnetic resonance spectroscopy was applied to study free radicals in soy bean seed after gamma irradiation and to establish the potential of these radiation induced free radicals as the indicator of the radiation treatment. The radiation doses administered to the samples were 1 to 30 kGy. A stable doublet signal was detected at g = 2.0279 with hyperfine coupling constant of 2.8 mT, produced only by radiolysis. This signal can be used to identify irradiated soy bean seed samples. With the increase of the radiation dose the central line intensity and the intensities of the satellite lines showed almost a linear rise having linear correlation factors of 0.99724 and 0.99996, respectively. Thermal treatment at 373 deg K in air was studied. No line specific to thermolysis was observed. The spectrometer was operated with power 0.253 mW, microwave frequency 9.74 GHz, modulation frequency 100 kHz and scan range 10 mT. To study the stability of the signal, EPR spectra were obtained from the irradiated skin part of soy bean seeds samples following 1 and 90 days of storage after radiation treatment. The two satellite lines of g left = 2.0279 and g right 1.99529 were detected in all samples. This suggests that the signal is associated with a stable radical and therefore, the detection of a particular free radical as a marker of irradiation is proposed

  15. Irradiation Effects of Electron Beam on Optical Fibers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Kyu; Cho, Gyu Seong [KAIST, Daejeon (Korea, Republic of); Choi, Hong Gu; Oh, Kyung Hwan [Yonsei University, Seoul (Korea, Republic of); Cho, Ho Jin [Nucron Co. Ltd., Seoul (Korea, Republic of)

    2009-10-15

    The surveillance or monitoring systems used in space station, nuclear power plant and nuclear waste repository, are often equipped with optical fibers to remotely locating expensive camera systems so as to protect them from direct irradiation. Especially in nuclear power plant and nuclear waste repository, irradiation by gamma-ray and beta-ray are most concerned. The effective life-time of such surveillance system may depend on the soundness of the optical fiber because it is the component to be exposed the high intensity of radiation field by purpose. Though the degradation of mechanical properties such as hardness and elasticity may occur but the degradation of the optical property such as spectral transmittance is the most possible cause of the effective life-time limitation. Generally 30 % reduction of light signal transmittance is considered as the life-time threshold point of such optical systems. In this paper, we studied irradiation effects on spectral transparency of various commonly-used optical fibers with high energy electron beam to conveniently simulate the both gamma-ray and beta-ray irradiation situation.

  16. Electron beam irradiation effects on xanthan gum. Rheological aspects

    International Nuclear Information System (INIS)

    Vieira, F.F.; Del Mastro, N.L.

    2001-01-01

    The paper describes the application of electron beam irradiation to xanthum gum as used as ingredient by the food or cosmetics industry in order to establish their radiosensitivity. The edible powder of xanthum gum samples were irradiated in 1mm thick layers of Petri dishes covered by a transparent PVC of films using an EB accelerator Dynamitron (Radiation Dynamics Inc.) model JOB 188, dose rate 11.17 kGy/s, 0.637 MeV, 1.78 mA, 5 kGy per passage, 3.36 m min -1 with doses of 5, 10, 20 and 50kGy. One % aqueous solutions from irradiated and non-irradiated xanthum gum were prepared and the radiation effects were measured following viscosity changes at 25 deg. C using a Brookfield viscometer; model DVIII, spindel L, with Rheocalc software. Viscosity measurements were performed according to our previous experience and the results are the mean of at least 3 experiments

  17. An experimental investigation of wastewater treatment using electron beam irradiation

    Science.gov (United States)

    Emami-Meibodi, M.; Parsaeian, M. R.; Amraei, R.; Banaei, M.; Anvari, F.; Tahami, S. M. R.; Vakhshoor, B.; Mehdizadeh, A.; Fallah Nejad, N.; Shirmardi, S. P.; Mostafavi, S. J.; Mousavi, S. M. J.

    2016-08-01

    Electron beam (EB) is used for disinfection and treatment of different types of sewage and industrial wastewater. However, high capital investment required and the abundant energy consumed by this process raise doubts about its cost-effectiveness. In this paper, different wastewaters, including two textile sewages and one municipal wastewater are experimentally studied under different irradiation strategies (i.e. batch, 60 l/min and 1000 m3/day) in order to establish the reliability and the optimum conditions for the treatment process. According to the results, EB improves the efficiency of traditional wastewater treatment methods, but, for textile samples, coagulation before EB irradiation is recommended. The cost estimation of EB treatment compared to conventional methods shows that EB has been more expensive than chlorination and less expensive than activated sludge. Therefore, EB irradiation is advisable if and only if conventional methods of textile wastewater treatment are insufficient or chlorination of municipal wastewater is not allowed for health reasons. Nevertheless, among the advanced oxidation processes (AOP), EB irradiation process may be the most suitable one in industrial scale operations.

  18. Optical properties of electron-irradiated gallium phosphide

    International Nuclear Information System (INIS)

    Brailovskii, E.Yu.; Grigoryan, N.E.; Eritsyan, G.N.

    1980-01-01

    Results of optical absorption and photoconductivity measurements in the 0.1 to 2.4 eV range of GaP crystals irradiated with 7.5 and 50 MeV electrons are presented. The absorption of irradiated crystals near the edge can be represented by two exponential regions. In the free carrier absorption region one can observe as a result of irradiation a decrease of the power index p in the dependence α proportional to lambdap. Photoconductivity with long-time relaxation takes place in the spectral interval where the additional absorption is observed. The quenching of residual conductivity can be observed at hν=1.0eV. Variations in absorption and photoconductivity are attributed to the 'tails' of density states near the zone edges arising at introduction of both point defects and disordered regions. At hν=2.1eV one can observe a resonance band which is attributed to intra-centre transitions on point defects. A recovery of the optical properties of GaP at annealing is studied. In heavily irradiated GaP crystals point defects can form gatherings which display themselves as disordered regions. (author)

  19. Physicochemical Study of Irradiated polypropylene/Organo :Modified Montmorillonite Composites by Using Electron Beam Irradiation Technique

    International Nuclear Information System (INIS)

    Hassan, M.S.

    2008-01-01

    Polypropylene/ Organo modified montmorillonite composites (PP/ OMMT) were prepared by melt blending with a twin screw extruder. The thermal properties by thermo gravimetric analysis (TGA), the dispersion of OMMT of macromolecules by X-ray diffraction (XRD), mechanical properties and the morphology by scanning electron microscopy (SEM) were investigated. The effect of electron beam irradiation on these properties was also studied. The results showed an intercalation between the silicate layers and the PP polymer matrix. The (PP/ OMMT) composites exhibit higher thermal stability and lower mechanical properties than pure polypropylene

  20. Oxidative decomposition of aromatic hydrocarbons by electron beam irradiation

    Science.gov (United States)

    Han, Do-Hung; Stuchinskaya, Tatiana; Won, Yang-Soo; Park, Wan-Sik; Lim, Jae-Kyong

    2003-05-01

    Decomposition of aromatic volatile organic compounds (VOCs) under electron beam irradiation was studied in order to examine the kinetics of the process, to characterize the reaction product distribution and to develop a process of waste gas control technology. Toluene, ethylbenzene, o-, m-, p-xylenes and chlorobenzene were used as target materials. The experiments were carried out at doses ranging from 0.5 to 10 kGy, using a flow reactor utilized under electron beam irradiation. Maximum degrees of decomposition carried out at 10 kGy in air environment were 55-65% for “non-chlorinated” aromatic VOC and 85% for chlorobenzene. It was found that a combination of aromatic pollutants with chlorobenzene would considerably increase the degradation value up to nearly 50% compared to the same compounds in the absence of chlorine groups. Based on our experimental observation, the degradation mechanism of the aromatic compounds combined with chloro-compound suggests that a chlorine radical, formed from EB irradiation, induces a chain reaction, resulting in an accelerating oxidative destruction of aromatic VOCs.

  1. Electron arc therapy: chest wall irradiation of breast cancer patients

    International Nuclear Information System (INIS)

    McNeely, L.K.; Jacobson, G.M.; Leavitt, D.D.; Stewart, J.R.

    1988-01-01

    From 1980 to October 1985 we treated 45 breast cancer patients with electron arc therapy. This technique was used in situations where optimal treatment with fixed photon or electron beams was technically difficult: long scars, recurrent tumor extending across midline or to the posterior thorax, or marked variation in depth of target tissue. Forty-four patients were treated following mastectomy: 35 electively because of high risk of local failure, and 9 following local recurrence. One patient with advanced local regional disease was treated primarily. The target volume boundaries on the chest wall were defined by a foam lined cerrobend cast which rested on the patient during treatment, functioning as a tertiary collimator. A variable width secondary collimator was used to account for changes in the radius of the thorax from superior to inferior border. All patients had computerized tomography performed to determine Internal Mammary Chain depth and chest wall thickness. Electron energies were selected based on these thicknesses and often variable energies over different segments of the arc were used. The chest wall and regional node areas were irradiated to 45 Gy-50 Gy in 5-6 weeks by this technique. The supraclavicular and upper axillary nodes were treated by a direct anterior photon field abutted to the superior edge of the electron arc field. Follow-up is from 10-73 months with a median of 50 months. No major complications were observed. Acute and late effects and local control are comparable to standard chest wall irradiation. The disadvantages of this technique are that the preparation of the tertiary field defining cast and CT treatment planning are labor intensive and expensive. The advantage is that for specific clinical situations large areas of chest wall with marked topographical variation can be optimally, homogeneously irradiated while sparing normal uninvolved tissues

  2. New crosslinked polyvinyl chloride insulated wire by electron beam irradiation

    International Nuclear Information System (INIS)

    Takahata, Norio; Shingyouchi, Kazuo; Sato, Masakatsu; Sasaki, Hidemi; Terunuma, Haruji

    1978-01-01

    The polyvinyl chloride-coated wires crosslinked by electron beam irradiation have made rapid progress as electric and electronic wiring material and grown to hold a firm position in this field. In response to the requirements for wires with the advance of electronic equipments, Hitachi Cable Ltd. developed a peculiar graft polymer consisting of chlorinated polyethylene and polyvinyl chloride. To this polymer, the characteristics of a very wide range from toughness to flexibility can be given, and the crosslinked polyvinyl chloride wires utilizing these characteristics were put in practical use. Many kinds of the wires were developed as follows; 105 deg. C rating crosslinked vinyl-coated wires authorized by UL and CSA standards, crosslinked vinyl-coated wires with excellent flexibility, high strength crosslinked vinyl-coated wires with thin coating and crosslinked vinyl-coated wires for automobiles. They are expected to be developed into other new fields and applications. (Kobatake, H.)

  3. A set of dosimetry systems for electron beam irradiation

    International Nuclear Information System (INIS)

    Lin Min; Lin Jingwen; Chen Yundong; Li Huazhi; Xiao Zhenhong; Gao Juncheng

    1999-01-01

    To follow the rapid development of radiation processing with electron beams, it is urgent to set up a set of dosimetric standards to provide Quality Assurance (QA) of electron beam irradiation and unify the values of the quality of the absorbed dose measurements for electron beams. This report introduces a set of dosimetry systems established in Radiometrology Center of China Institute of Atomic Energy (RCCIAE), which have been or will be used as dosimetric standards in the Nuclear Industry System (NIS) in China. For instance, the potassium (silver) dichromate and ceric-cerous sulfate dosimetry systems will be used as standard dosimeters, while alanine-ESR dosimetry system as a transfer dosimeter, and FJL-01 CTA as a routine dosimeter. (author)

  4. Comparison of three techniques for skin total irradiation with electrons

    International Nuclear Information System (INIS)

    Batista, Delano V.S.; Bardella, Lucia H.; Rosa, Luiz A.R. da

    2011-01-01

    This paper compared three techniques of skin total irradiation with electrons: 1) horizontal positioning, 2) vertical positioning - rotatory technique and 3) vertical positioning - six fields technique. For that, a anthropomorphic phantom was positioned according to the recommendation for each technique and was i radiated at the linear accelerator by using the 6 MeV electrons. Radiochromic films were positioned on the surface in various regions of the phantom for measurement of absorbed dose. A ionization chamber was positioned inside of equivalent issue plates for dose evaluation due to the photons produced by electron stopping. The technique 2 and 3 have shown too similar in the results and number or discrepant points (8 and 10 respectively) of prescription lower than the technique 1 (22 points). The total body dose of photons of the 1, 2 and 3 techniques was 2.2%, 5.3% and 5.2% respectively

  5. Radiation Safety of Gamma, Electron and X Ray Irradiation Facilities. Specific Safety Guide (Spanish Edition)

    International Nuclear Information System (INIS)

    2015-01-01

    The objective of this Safety Guide is to provide recommendations on how to meet the requirements of the BSS with regard to irradiation facilities. This Safety Guide provides specific, practical recommendations on the safe design and operation of gamma, electron and X ray irradiators for use by operating organizations and the designers of these facilities, and by regulatory bodies. SCOPE. The facilities considered in this publication include five types of irradiator, whether operated on a commercial basis or for research and development purposes. This publication is concerned with radiation safety issues and not with the uses of irradiators, nor does it cover the irradiation of product or its quality management. The five types of irradiator are: - Panoramic dry source storage irradiators; - Underwater irradiators, in which both the source and the product being irradiated are under water; - Panoramic wet source storage irradiators; - Electron beam irradiation facilities, in which irradiation is performed in an area that is potentially accessible to personnel, but that is kept inaccessible during the irradiation process; - X ray irradiation facilities, in which irradiation is performed in an area that is potentially accessible to personnel, but that is kept inaccessible during the irradiation process. Consideration of non-radiation-related risks and of the benefits resulting from the operation of irradiators is outside the scope of this Safety Guide. The practices of radiotherapy and radiography are also outside the scope of this Safety Guide. Category I gamma irradiators (i.e. 'self-shielded' irradiators) are outside the scope of this Safety Guide

  6. Electron-irradiation-induced crystallization of amorphous orthophosphates

    International Nuclear Information System (INIS)

    Meldrum, A.; Ewing, R.C.; Boatner, L.A.

    1996-12-01

    Amorphous LaPO 4 , EuPO 4 , GdPO 4 , ScPO 4 , and fluorapatite [Ca 5 (PO 4 ) 3 F] were irradiated by electron beam in a TEM. Irradiations were done at -150 to 300 C, 80 to 200 keV, and current densities from 0.3 to 16 A/cm 2 . In all cases, the materials crystallized to form a randomly oriented polycrystalline assemblage. Crystallization is driven dominantly by inelastic processes, although ballistic collisions with target nuclei can be important above 175 keV, particularly in apatite. Using a high current density, crystallization is so fast that continuous lines of crystallites can be ''drawn'' on the amorphous matrix

  7. Electron spin resonance intercomparison studies on irradiated foodstuffs

    International Nuclear Information System (INIS)

    Raffi, J.

    1992-01-01

    The results of intercomparison studies organized by the Community Bureau of Reference on the use of electron spin resonance spectroscopy for the identification of irradiated food are presented. A qualitative intercomparison was carried out using beef and trout bones, sardine scales, pistachio nut shells, dried grapes and papaya. A quantitative intercomparison involving the use of poultry bones was also organized. There was no difficulty in identifying meat bones, dried grapes and papaya. In the case of fish bones there is a need for further kinetic studies using different fish species. The identification of pistachio nut shells is more complicated and further research is needed prior to the organization of a further intercomparison. Laboratories were able to distinguish between chicken bones irradiated in the range 1 to 3 KGy or 7 to 10 KGy although there was a partial overlap between the results from different laboratories

  8. Electron spin resonance intercomparison studies on irradiated foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    Raffi, J [CEA Centre d` Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (FR)

    1992-07-01

    The results of intercomparison studies organized by the Community Bureau of Reference on the use of electron spin resonance spectroscopy for the identification of irradiated food are presented. A qualitative intercomparison was carried out using beef and trout bones, sardine scales, pistachio nut shells, dried grapes and papaya. A quantitative intercomparison involving the use of poultry bones was also organized. There was no difficulty in identifying meat bones, dried grapes and papaya. In the case of fish bones there is a need for further kinetic studies using different fish species. The identification of pistachio nut shells is more complicated and further research is needed prior to the organization of a further intercomparison. Laboratories were able to distinguish between chicken bones irradiated in the range 1 to 3 KGy or 7 to 10 KGy although there was a partial overlap between the results from different laboratories.

  9. Fluence behavior of polyethylene films irradiated with high energy electrons

    International Nuclear Information System (INIS)

    Pino, Eddy Segura; Silva, Leonardo G. Andrade e

    1999-01-01

    Polymers are viscoelastic materials at all temperatures, so that mechanical loads induce time dependable deformations. The recovery of these deformations, on load release, take some time and it is not always recovered completely. The main objective of this work was to analyse the creep behavior of electron irradiated polyethylene films. From the experimental results, it was sated that polyethylene creeps less with an increase on irradiation dose and also that creep recovery in this material increases with doses but it is not complete. This behavior can be attributed to the crosslinking effect witch stabilize elements of the molecular structure of the polyethylene, thus reducing their mobility and so inhibiting the creep mechanism. The partial creep recovery could be also attributed to the reticulation effect and to the polyethylene plastic behavior. Additional information on the creep behavior was obtained by fitting the experimental data with exponential functions and evaluating the mathematical parameters with a modified Kelvin-Voigt mechanical model. (author)

  10. Precipitate resolution in an electron irradiated ni-si alloy

    Science.gov (United States)

    Watanabe, H.; Muroga, T.; Yoshida, N.; Kitajima, K.

    1988-09-01

    Precipitate resolution processes in a Ni-12.6 at% Si alloy under electron irradiation have been observed by means of HVEM. Above 400°C, growth and resolution of Ni 3Si precipitates were observed simultaneously. The detail stereoscopic observation showed that the precipitates close to free surfaces grew, while those in the middle of a specimen dissolved. The critical dose when the precipitates start to shrink increases with increasing the depth. This depth dependence of the precipitate behavior under irradiation has a close relation with the formation of surface precipitates and the growth of solute depleted zone beneath them. The temperature and dose dependence of the resolution rate showed that the precipitates in the solute depleted zone dissolved by the interface controlled process of radiation-enhanced diffusion.

  11. Comparative study on disinfection potency of spore forming bacteria by electron-beam irradiation and gamma-ray irradiation

    International Nuclear Information System (INIS)

    Takizawa, Hironobu; Suzuki, Satoru; Suzuki, Tetsuya; Takama, Kozo; Hayashi, Toru; Yasumoto, Kyoden.

    1990-01-01

    Along with gamma-ray irradiation, electron-beam irradiation (EB) is a method to disinfect microorganisms which cause food decomposition and food-poisoning. The present study was undertaken to compare sterilization efficacy of EB and gamma-ray irradiation on bacterial spores and vegetative cells under various conditions. Spores of Bacillus pumilus, a marker strain for irradiation study, and Bacillus stearothermophilus known as a thermophilic bacteria were irradiated by electron-beam and gamma-ray separately at irradiation dose of 0 to 10 kGy on combination of wet/dry and aerobic/anaerobic conditions. Sterilization effect of irradiation on spores was evaluated by colony counting on agar plates. Results showed that both EB and gamma-ray irradiation gave sufficient sterilization effect on spores, and the sterilization effect increased exponentially with irradiation dose. The sterilization effect of gamma-ray irradiation was higher than that of EB in all cases. Higher disinfection effect was observed under aerobic condition. The present study suggests that oxygen supply in EB is more important than gamma-ray irradiation. No results suggesting that chlorine ion at 0.1 ppm (as available chlorine concentration) enhanced the sterilization efficacy of either EB or gamma-ray irradiation was obtained under any conditions examined. (author)

  12. Comparative study on disinfection potency of spore forming bacteria by electron-beam irradiation and gamma-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Takizawa, Hironobu; Suzuki, Satoru; Suzuki, Tetsuya; Takama, Kozo [Hokkaido Univ., Hakodate (Japan). Faculty of Fisheries; Hayashi, Toru; Yasumoto, Kyoden

    1990-10-01

    Along with gamma-ray irradiation, electron-beam irradiation (EB) is a method to disinfect microorganisms which cause food decomposition and food-poisoning. The present study was undertaken to compare sterilization efficacy of EB and gamma-ray irradiation on bacterial spores and vegetative cells under various conditions. Spores of Bacillus pumilus, a marker strain for irradiation study, and Bacillus stearothermophilus known as a thermophilic bacteria were irradiated by electron-beam and gamma-ray separately at irradiation dose of 0 to 10 kGy on combination of wet/dry and aerobic/anaerobic conditions. Sterilization effect of irradiation on spores was evaluated by colony counting on agar plates. Results showed that both EB and gamma-ray irradiation gave sufficient sterilization effect on spores, and the sterilization effect increased exponentially with irradiation dose. The sterilization effect of gamma-ray irradiation was higher than that of EB in all cases. Higher disinfection effect was observed under aerobic condition. The present study suggests that oxygen supply in EB is more important than gamma-ray irradiation. No results suggesting that chlorine ion at 0.1 ppm (as available chlorine concentration) enhanced the sterilization efficacy of either EB or gamma-ray irradiation was obtained under any conditions examined. (author).

  13. Electron beam irradiation: laboratory and field studies of cowpea seeds

    International Nuclear Information System (INIS)

    Srinivasan, K.; Chauhan, S.K.; Prasad, T.V.; Pramod, R.; Verma, V.P.; Petwal, V.; Dwivedi, J.; Bhalla, S.

    2015-01-01

    Cowpea (Vigna unguiculata) rich in protein and vitamins is emerging as one of the most important food legumes to tackle malnutrition. Pulse beetles (Callosobruchus chinensis and C. maculatus) are the pests of economic importance causing enormous losses during storage. Although various pest management strategies exist for the control of these pests, environmental concerns necessitate developing ecofriendly strategies. Electron beam (EB) irradiation has the potential to be a viable, non-chemical, residue-free strategy for management of pulse beetles during storage, but higher doses affect seed germination and viability. Hence, the present investigation was taken up to analyse the dosage effect of the irradiation on seed attributes of cowpea. Healthy cowpea seeds were irradiated with low energy electrons at different doses viz., 180, 360, 540, 720, 900, 1080, 1260, 1440 and 1620 Gy at 500 keV using the EB Accelerator facility at Raja Ramanna Centre for Advanced Technology, Indore. EB irradiated seeds were tested for physiological viz., germination, seedling vigour and vigour index and biochemical parameters viz., electrical conductivity of seed leachate, seed viability/tetrazolium test and dehydrogenase activity. Germination and vigour of the irradiated seeds were evaluated as per the ISTA Rules (ISTA, 1996). Vigour index was calculated as the product of germination percentage and seedling vigour. About 3,000 irradiated seeds from each dose were grown in the field at the Experimental farm, National Bureau of Plant Genetic Resources, New Delhi. Seeds harvested from 1500 individual plants of M 1 generation from each dose (50 seeds from each plant individually) were sown in next season and observed for chlorophyll mutations, if any. Results revealed that doses upto 1080 Gy (88%) did not affect the germination of cowpea seeds drastically as compared to untreated seeds (98%). Lower doses viz., 180 and 360 Gy had no impact on vigour components while higher doses (1080 Gy

  14. Electron beam irradiation: novel technology for phytosanitary purposes

    International Nuclear Information System (INIS)

    Bhalla, Shashi; Srinivasan, K.; Dwivedi, J.; Gautam, S.; Sharma, Arun

    2015-01-01

    In the WTO regime, flow of agricultural commodities has increased, posing risk of inadvertent introduction of exotic pests. This can be minimized by undertaking quarantine measures. Quarantine/phytosanitary disinfestation treatments demand a very high level of security as the pest tolerance in quarantine is zero. Methyl bromide, a potent fumigant has been restricted in its use due to ozone depleting effect. Also, the conventional chemicals/fumigants being used world over are being restricted globally because of the various associated problems. Therefore, there is a need for an alternative ecofriendly strategy for controlling the pests. Irradiation, an approved technology by International Plant Protection Convention, appears to be a viable, nonchemical, residue-free strategy. Disinfestation of pulses with low energy electron irradiation potentially will have less deleterious effects on commodity quality than irradiation with other sources. Internationally, new radiation generating sources as Electron beam (EB) are being explored to meet import standards of quality and quarantine. The EB has a machine source and can be simply switched on or off. Irradiation of legume seeds viz., blackgram, greengram and soybean infested with pulse beetles (Callosobruchus maculatus and C. chinensis) at different doses at an energy level of 500 keV using the Accelerator facility at Raja Ramanna Centre for Advanced Technology, Indore revealed the dose-dependent effects on the insect growth parameters. Adult emergence from seeds infested with different stages was negligible and eggs laid by beetles that survived treatment did not develop into adults at higher doses. The lower doses viz., 170, 340 and 510 Gy on the other hand caused sterility effect on the insect but showed stimulatory effect on the physiological seed parameters . viz., seedling vigour and vigour index. Electron beam irradiation has a great potential for use in the disinfestation for phytosanitary purposes. Nevertheless

  15. Comparison of electron beam and gamma irradiation for the sterilization of allograft

    International Nuclear Information System (INIS)

    Jong il Choi; Nak Yun Sung; Hee Sub Lee; Jae Hun Kim; Myung Woo Byun; Ju Woon Lee

    2008-01-01

    Full text: For human use, it is necessary to sterilize the allograft in order to reduce the risk of infections and associated complications. In this study, we compared the effects of electron beam and gamma irradiation for the sterilization of the demineralized bone matrix (DBM) in a carboxymethylcellulose (CMC) carrier with regard to the physiological and osteoinductive properties. The CMC carrier was irradiated at the various doses. and the viscosity of the irradiated CMC was measured. The viscosity of the CMC irradiated with electron beam was higher than that with gamma ray. Also, the addition of vitamin C as the radical scavenger and irradiation at -70 degree C were shown to be effective in preventing the degradation of CMC by the irradiation. To investigate the effect of irradiation on the osteoinduction of DBM, alkaline phosphatase (ALP) activity with C2C12 cells was measured. The ALP activity of DBM in CMC was higher when irradiated with the electron beam compared with the gamma ray. The bone morphogenetic proteins (BMP) were extracted from DBM irradiated with electron beam and gamma ray, and it was found that the extraction efficiency of BMP was higher from DBM irradiated with the electron beam. This was reasoned for the higher APL activity of the electron beam irradiated DBM. With the advantages of electron beam such as short processing time, in-line processing, and low equipment cost, these results suggest that electron beam irradiation is recommendable for the sterilization of DBM allograft. (Author)

  16. Investigations on the optical, thermal and surface modifications of electron irradiated L-threonine single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ramesh Kumar, G.; Gokul Raj, S. [Department of Physics, Presidency College, Chepauk, Chennai 600005 (India); Bogle, K.A.; Dhole, S.D.; Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 411007 (India); Mohan, R. [Department of Physics, Presidency College, Chepauk, Chennai 600005 (India)], E-mail: professormohan@yahoo.co.in

    2008-06-15

    L-Threonine single crystals have been irradiated by 6 MeV electrons. Irradiated crystals at various electron fluences were subjected to various techniques such as UV-vis-NIR, atomic force microscopy (AFM) and thermomechanical analyses. Thermal strength of the irradiated crystals has also been studied through differential scanning calorimetry (DSC) measurements. The results have been discussed in detail.

  17. Electron Beam Irradiated Intercalated CNT Yarns For Aerospace Applications

    Science.gov (United States)

    Waters, Deborah L.; Gaier, James R.; Williams, Tiffany S.; Lopez Calero, Johnny E.; Ramirez, Christopher; Meador, Michael A.

    2015-01-01

    Multi-walled CNT yarns have been experimentally and commercially created to yield lightweight, high conductivity fibers with good tensile properties for application as electrical wiring and multifunctional tendons. Multifunctional tendons are needed as the cable structures in tensegrity robots for use in planetary exploration. These lightweight robust tendons can provide mechanical strength for movement of the robot in addition to power distribution and data transmission. In aerospace vehicles, such as Orion, electrical wiring and harnessing mass can approach half of the avionics mass. Use of CNT yarns as electrical power and data cables could reduce mass of the wiring by thirty to seventy percent. These fibers have been intercalated with mixed halogens to increase their specific electrical conductivity to that near copper. This conductivity, combined with the superior strength and fatigue resistance makes it an attractive alternative to copper for wiring and multifunctional tendon applications. Electron beam irradiation has been shown to increase mechanical strength in pristine CNT fibers through increased cross-linking. Both pristine and intercalated CNT yarns have been irradiated using a 5-megavolt electron beam for various durations and the conductivities and tensile properties will be discussed. Structural information obtained using a field emission scanning electron microscope, energy dispersive X-ray spectroscopy (EDS), and Raman spectroscopy will correlate microstructural details with bulk properties.

  18. Radiation disinfestation of used packagings: irradiation trials with electron beams

    International Nuclear Information System (INIS)

    Ignatowicz, S.; Zaedee, I.

    1994-01-01

    Used bags, sacks and other packagings are often infested with insects and mites - pest of stored products. Such packagings provide a source of infestation of a new lot or unit of agricultural products. Cleaning of repeatedly used packages is the most important preventive method. After using, the bags and sacks should be carefully beaten with a mechanical or hand beater. When pests are found, the packages should be disinfested with hot air or hot water. Larger numbers of bags are usually fumigated in a special fumigation chamber. Disinfestation by radiation processing is potentially a feasible substitute for chemical fumigation. In the present paper trials of radiation disinfestation of used bags are described and discussed. Information about using electron beams for pest disinfestation of jute and polyvinyl chloride bags (plastic bags) is provided. The absorbed dose is the most important irradiation process parameter. The lethal effects equivalent to chemical insecticides are obtained by high doses of ionizing radiation. Control of insect and/or mite infestation of the repeatedly used packagings may be secured by ionizing radiation applied at 2-3 kGy. These doses result in complete mortality of stored product pests within a few days. The radiation must penetrate deeply into the target product at sufficient level. Gamma rays and X-rays penetrate into the treated products easily but electron radiation penetrating is much lower, depending on electron energy applied. The results of this study indicate that bags made of polyvinyl chloride may be disinfested with electron beams when are created as separate units or batches up to 50 bags. Penetrability of jute bags is lower than the plastic bags. Therefore the jute bags should be irradiated with electrons as batches containing no more than 30 bags. (author)

  19. Void swelling behaviour of austenitic stainless steel during electron irradiation

    International Nuclear Information System (INIS)

    Sheng Zhongqi; Xiao Hong; Peng Feng; Ti Zhongxin

    1994-04-01

    The irradiation swelling behaviour of 00Cr17Ni14Mo2 austenitic stainless steel (AISI 316L) was investigated by means of high voltage electron microscope. Results showed that in solution annealed condition almost no swelling incubation period existed, and the swelling shifted from the transition period to the steady-state one when the displacement damage was around 40 dpa. In cold rolled condition there was evidently incubation period, and when the displacement damage was up to 84 dpa the swelling still remained in the transition period. The average size and density of voids in both conditions were measured, and the factors, which influenced the void swelling, were discussed. (3 figs.)

  20. Effect of radiation on fruit pollen germination and distant hybridization compatibility

    International Nuclear Information System (INIS)

    Li Jing; Shang Xiaoli

    2006-01-01

    Pollens of Zhouxingshantao peach trees, apricot cultivar Katy and plum cultivar Friar were irradiated by different doses of 60 Co γ-rays and ultraviolet to study the radiation effect on the pollen germination and distant hybridization settings. The germination percentages of the pollen irradiated by 60 Co γ-rays and ultraviolet were lower than those of the controls. The pollens of the tested fruits have different sensitivities of 60 Co γ-rays and ultraviolet: the Friar pollen was the most sensitive to the radiation, and the Katy was the least. With the germinate percentages of the irradiated pollen dropping, the distant hybridization fruit setting percentage also lowered. (authors)

  1. Electron dosimetry in irradiation processing with rad-hard diodes

    International Nuclear Information System (INIS)

    Santos, Thais Cavalheri dos

    2012-01-01

    This work had the aim of the development of dosimetric systems based on Si special diodes, resistant to radiation damage to online monitoring of irradiation processing using 1.5 MeV electrons energy and for relative dosimetry and clinical electron beam scanning within an energy range of 6 MeV up to 21 MeV. The diodes used were produced by Float Zone standard (FZ), Magnetic Czochralski (MCz) and epitaxy growth (EPI) methods. In order to use the diodes as detectors, they were fixed on alumina base to allow the connection of the polarization electrodes and the signals extraction. After the diode assembly on the base, each one was housed in a black acrylic probe with aluminized Mylar® window and LEMO® connector. With the devices operating in photovoltaic mode, the integration of the current signals as a function of irradiation time allowed obtain the charge produced in the sensitive volume of each diode irradiated. The electron accelerator used for high doses irradiation was the DC 1500/25/4 JOB 188 of the 1.5 MeV installed at the Radiation Technology Center of the IPEN/CNEN-SP. The current profile as function of exposure time, the response repeatability, the sensitivity as function of absorbed dose and the dose response curve were studied for each device. In comparison to FZ diode, we observed a greater decrease in the sensitivity for MCz diode, and good repeatability in both cases. Also, the increasing of the charge with the absorbed dose was well fitted by a second order polynomial function. In the EPI diode characterization, this one exhibited repeatability better than CTA dosimeters applied routinely in radiation processing. The above results indicate the potential use of these radiation hardness Si diodes in online dosimetry to high doses applications. For low doses irradiation were used the linear accelerators KD2 and Primus, both manufactured by Siemens and located at Sirio-Libanes Hospital. The diodes responses were evaluated for electron beams within the

  2. Energetic Ion and Electron Irradiation of the Icy Galilean Satellites

    Science.gov (United States)

    Cooper, John F.; Johnson, Robert E.; Mauk, Barry H.; Garrett, Henry B.; Gehrels, Neil

    2001-01-01

    Galileo Orbiter measurements of energetic ions (20 keV to 100 MeV) and electrons (20-700 keV) in Jupiter's magnetosphere are used, in conjunction with the JPL electron model (less than 40 MeV), to compute irradiation effects in the surface layers of Europa, Ganymede, and Callisto. Significant elemental modifications are produced on unshielded surfaces to approximately centimeter depths in times of less than or equal to 10(exp 6) years, whereas micrometer depths on Europa are fully processed in approximately 10 years. Most observations of surface composition are limited to optical depths of approximately 1 mm, which are indirect contact with the space environment. Incident flux modeling includes Stormer deflection by the Ganymede dipole magnetic field, likely variable over that satellite's irradiation history. Delivered energy flux of approximately 8 x 10(exp 10) keV/square cm-s at Europa is comparable to total internal heat flux in the same units from tidal and radiogenic sources, while exceeding that for solar UV energies (greater than 6 eV) relevant to ice chemistry. Particle energy fluxes to Ganymede's equator and Callisto are similar at approximately 2-3 x 10(exp 8) keV/square cm-s with 5 x 10(exp 9) at Ganymede's polar cap, the latter being comparable to radiogenic energy input. Rates of change in optical reflectance and molecular composition on Europa, and on Ganymede's polar cap, are strongly driven by energy from irradiation, even in relatively young regions. Irradiation of nonice materials can produce SO2 and CO2, detected on Callisto and Europa, and simple to complex hydrocarbons. Iogenic neutral atoms and meteoroids deliver negligible energy approximately 10(exp 4-5) keV/square cm-s but impacts of the latter are important for burial or removal of irradiation products. Downward transport of radiation produced oxidants and hydrocarbons could deliver significant chemical energy into the satellite interiors for astrobiological evolution in putative sub

  3. Microporous polyurethane-acrylamide film cured by electron beam irradiation

    International Nuclear Information System (INIS)

    Ando, Masayuki; Goto, Takakazu; Tsuchiya, Mitsuru; Uryu, Toshiyuki

    1988-01-01

    The morphology and aggregation structure of electron beam (EB)-cured microporous polyurethane-acrylamide film was investigated. The urethane-acrylamide prepolymer was synthesized by the reaction of poly(butylene adipate)diol, diphenylmethane diisocyanate, and N-(hydroxymethyl)acrylamide. It was found from scanning electron microscopy that the urethane-acrylamide film, which was prepared by using a methyl ethyl ketone and dimethylformamide (3:1 v/v) mixture as casting solvent, had a microporous structure with pore size of several micrometers, and that the morphology was fixed by EB irradiation. The pore volume of the EB-cured microporous film was determined to be about 460 mm 3 g -1 by mercury porosimetry. The micropores were not destroyed even after immersing in solvent, possibly because the cured film had high crystallinity and dense crosslinking. Moreover, it was found by X-ray photelectron spectroscopy that terminal portions of urethane-acrylamide were localized at the film surface. (author)

  4. Electron irradiation-induced destruction of carbon nanotubes in electron microscopes

    International Nuclear Information System (INIS)

    Molhave, Kristian; Gudnason, Sven Bjarke; Pedersen, Anders Tegtmeier; Clausen, Casper Hyttel; Horsewell, Andy; Boggild, Peter

    2007-01-01

    Observations of carbon nanotubes under exposure to electron beam irradiation in standard transmission electron microscope (TEM) and scanning electron microscope (SEM) systems show that such treatment in some cases can cause severe damage of the nanotube structure, even at electron energies far below the approximate 100 keV threshold for knock-on damage displacing carbon atoms in the graphene structure. We find that the damage we observe in one TEM can be avoided by use of a cold finger. This and the morphology of the damage imply that water vapour, which is present as a background gas in many vacuum chambers, can damage the nanotube structure through electron beam-induced chemical reactions. Though, the dependence on the background gas makes these observations specific for the presently used systems, the results demonstrate the importance of careful assessment of the level of subtle structural damage that the individual electron microscope system can do to nanostructures during standard use

  5. Polyelectrolytes processing at pilot scale level by electron beam irradiation

    International Nuclear Information System (INIS)

    Martin, D.; Cirstea, E.; Craciun, G.; Ighigeanu, D.; Marin, Gheorghe G.

    2002-01-01

    Three years of research, combined with engineering activities, have culminated in the development of a new method of electron beam processing applicable up to the pilot scale level, namely, the polyelectrolytes (acrylamide - acrylic acid copolymers) electron beam processing. This new radiation processing method has been achieved by bilateral co-operation between the National Institute for Laser, Plasma and Radiation Physics (NILPRP) and the Electrical Design and Research Institute, EDRI - Bucharest. The polyelectrolytes electron beam (EB) processing was put in operation at EDRI, where, recently, an industrial electron accelerator of 2 MeV and 20 kW, manufactured by Institute of Nuclear Physics, Novosibirsk, Russia was installed in a specially designed irradiation facility. Automatic start-up via computer control makes it compatible with industrial processing. According to the first conclusions, which resulted from our experimental research with regard to acrylamide - acrylic acid copolymers production by EB irradiation, the proper physical and chemical characteristics can be well controlled by chemical composition to be treated and by suitable adjustment of absorbed dose and absorbed dose rate. So, it was possible to obtain a very large area of characteristics and therefore a large area of applications. The conversion coefficient is very high (> 98%) and concentration of the residual monomer is under 0.05%. The tests applied to some wastewaters from the vegetable oil plants demonstrated that the fatty substances, matters in suspension, chemical oxygen demand and biological oxygen demand over 5 days were much reduced, in comparison with classical treatment. Also, sedimentation time was around four times smaller and sediment volume was 60% smaller than the values obtained in case of classical treatment. The necessary EB absorbed dose for the acrylamide - acrylic acid aqueous solution polymerization, established by optimization of chemical composition and irradiation

  6. Effect of electron irradiation on hatchability and broiler performance of hatching eggs

    International Nuclear Information System (INIS)

    Castaneda, S.M.P.; Tellez, I.G.; Sanchez, R.E.; Quintana, L.J.A.; Bustos, R.E.

    1996-01-01

    The irradiation of foods employs the electromagnetic ionizing energy, and the gamma ray, the X ray and the electrons are used. The electrons are reduced mass particles and have negative electric charge. The difference between the gamma rays, X-ray and electron is the penetration level. The effective range on penetration of electron accelerator depends on the energy level, in practice the penetation of an electron beam in the foods is 5 mm for MeV. The objectives of this work were to evaluate the effects of electron irradiation on the hatchability, and to evaluate the productive parameters of chicken hatching from egg irradiated with electrons. (author). 15 refs., 6 tabs

  7. Structural and functional changes in the intenstine of irradiated and hypothermic irradiated rats : a scanning and transmission electron microscopic study

    International Nuclear Information System (INIS)

    Chaudhuri, S.; Chaudhuri, Swapna; Roy, Bijon

    1982-01-01

    Severe destructive changes in the intestine of rats following whole body exposure to gamma rays (832 rads) were observed by light microscope, scanning and transmission electron microscope studies. Hypothermia (15deg C rectal temperature) induced prior to irradiation protected the intestinal mucosa from destruction. A simultaneous study showed that glucose absorption decreased significantly in irradiated rats, whereas it was increased in hypothermic irradiated animals. (author)

  8. DETECTION OF SOME IRRADIATED NUTS BY ELECTRON SPIN RESONANCE (ESR) TECHNIQUE

    International Nuclear Information System (INIS)

    KHALLAF, M.F.; YASIN, N.M.N.; EL-NASHABY, F.M.; ALI, H.G.M.; EL-SHIEMY, S.M.

    2008-01-01

    The present investigation was carried out to establish the electron spin resonance (ESR) detection method for identifying irradiated nuts (almond and pistachio). Samples were irradiated with 2, 4 and 6 kGy and stored at room temperature (25± 2 0 C) for six months to study the possibility of detecting its previous irradiation treatments by ESR spectroscopy. Analysis was carried out just after irradiation treatment and during ambient storage period. The ESR signal intensities of irradiated samples were markedly increased correspondingly with irradiation dose as a result of free radicals generated by gamma irradiation so, all irradiated samples under investigation could be differentiated from non-irradiated ones immediately after irradiation treatment. The decay in radicals responsible of ESR signals showed the identification of irradiated almond (shell or edible part) and pistachio (edible part) was impossible after six months of ambient storage

  9. DETECTION OF SOME IRRADIATED NUTS BY ELECTRON SPIN RESONANCE (ESR) TECHNIQUE

    Energy Technology Data Exchange (ETDEWEB)

    KHALLAF, M F; YASIN, N M.N. [Food Science Dept., Faculty of Agriculture, Ain Shams University, Cairo (Egypt); EL-NASHABY, F M; ALI, H G.M.; EL-SHIEMY, S M [Nuclear Research Centre, Atomic Energy Authority, Cairo (Egypt)

    2008-07-01

    The present investigation was carried out to establish the electron spin resonance (ESR) detection method for identifying irradiated nuts (almond and pistachio). Samples were irradiated with 2, 4 and 6 kGy and stored at room temperature (25{+-} 2{sup 0}C) for six months to study the possibility of detecting its previous irradiation treatments by ESR spectroscopy. Analysis was carried out just after irradiation treatment and during ambient storage period. The ESR signal intensities of irradiated samples were markedly increased correspondingly with irradiation dose as a result of free radicals generated by gamma irradiation so, all irradiated samples under investigation could be differentiated from non-irradiated ones immediately after irradiation treatment. The decay in radicals responsible of ESR signals showed the identification of irradiated almond (shell or edible part) and pistachio (edible part) was impossible after six months of ambient storage.

  10. Size Control Technology of Silver Nanoparticles Using Electron Beam Irradiation

    International Nuclear Information System (INIS)

    Kang, Hyun Suk; Kim, Byungnam; Kim, Hye Won; Koo, Yong Hwan; Lee, Byung Cheol; Park, Ji Hyun; Bae, Hyung Bin; Park, Changmoon

    2013-01-01

    The manufacturing of silver nanoparticles using an electron beam is easy, fast, and highly productive, and it is possible at room temperature with no chemical residuals. Its various advantages therefore make this an important method for manufacturing nanoparticles such as silver, copper, and platinum. In particular, despite the use of electron beam irradiation, the results show that this method makes it possible to produce silver nanoparticles at low cost since low beam energy and low doses are used. This means that middle and high-energy electron beam accelerators are very expensive, but a low-energy electron beam accelerator has a relatively low cost of around 4-5 times, and mass production for a flow reaction without the need for extra radiation shielding is possible. Silver nanoparticles are of great interest to many researchers owing to their ability to be used in many applications such as catalysis, nanoelectronics, optical filters, electromagnetic interference shielding, surface Raman scattering, medical supplies, fabrics, cosmetics, hygiene and kitchen supplies, and electric home appliances

  11. Size Control Technology of Silver Nanoparticles Using Electron Beam Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyun Suk; Kim, Byungnam; Kim, Hye Won; Koo, Yong Hwan; Lee, Byung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Ji Hyun [Univ. of Science and Technology, Daejeon (Korea, Republic of); Bae, Hyung Bin [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Park, Changmoon [Chungnam National Univ., Daejeon (Korea, Republic of)

    2013-12-15

    The manufacturing of silver nanoparticles using an electron beam is easy, fast, and highly productive, and it is possible at room temperature with no chemical residuals. Its various advantages therefore make this an important method for manufacturing nanoparticles such as silver, copper, and platinum. In particular, despite the use of electron beam irradiation, the results show that this method makes it possible to produce silver nanoparticles at low cost since low beam energy and low doses are used. This means that middle and high-energy electron beam accelerators are very expensive, but a low-energy electron beam accelerator has a relatively low cost of around 4-5 times, and mass production for a flow reaction without the need for extra radiation shielding is possible. Silver nanoparticles are of great interest to many researchers owing to their ability to be used in many applications such as catalysis, nanoelectronics, optical filters, electromagnetic interference shielding, surface Raman scattering, medical supplies, fabrics, cosmetics, hygiene and kitchen supplies, and electric home appliances.

  12. Craniospinal axis irradiation: an improved electron technique for irradiation of the spinal axis

    International Nuclear Information System (INIS)

    Chun Li; Vijayakumar, S.; Myrianthopoulos, L.C.; Kuchnir, F.T.; Muller-Runkel, R.

    1994-01-01

    The authors review dosimetric features of craniospinal axis irradiation in the areas of matching cranial and spinal fields, with reference to normal structures within the spinal field. The implications of the use of photon or electron modalities for the spinal port were evaluated. A novel method of matching the cranial photon and the spinal electron fields involving a computer-aided junction design is presented, involving moving the photon beam in three steps to degrade its penumbra to match that of the electron field. Thermoluminescent dosimetry in a Rando phantom and computed tomography-based dose-volume histogram study for an illustrative paediatric case were used to compare dose to normal structures within the spinal field. Results show that the use of electrons for the spinal field leads to better sparing of deep seated normal structures. For bone marrow, the use of a customized bolus for the spinal field results in an improved dose distribution, making electrons potentially superior to photons for radiobiological reasons. (author)

  13. Application of pollen treated with ionizing radiation in grapes breeding

    International Nuclear Information System (INIS)

    Semin, V.S.

    1988-01-01

    Problem concerning the priority of investigations into transformation inducing using plant pollen irradiation method is raised. Data on investigations into grape predominant type pollen irradiation with rigid 1-100 Gy dose gamma rays are considered. Using grape seedling morphological index analysis it is shown that gene transformation inducing is possible using high dose pollen irradiation for cross pollination process. Advantages of the given method are indicated: application of irradiated pollen for pollination allows one to transmit certain characters to progeny at some stages - without impregnation (1); with pollen irradiation dose increase the number of male plant characters transmitted to progeny is reduced (2); deep recessive characters of one of the parent plants can be manifested in progeny or valuable neoplasms can even occur

  14. An Economic Analysis of Electron Accelerators and Cobalt-60 for Irradiating Food

    OpenAIRE

    Morrison, Rosanna Mentzer

    1989-01-01

    Average costs per pound of irradiating food are similar for the electron accelerator and cobalt-60 irradiators analyzed in this study, but initial investment costs can vary by $1 million. Irradiation costs range from 0.5 to 7 cents per pound and decrease as annual volumes treated increase. Cobalt-60 is less expensive than electron beams for annual volumes below 50 million pounds. For radiation source requirements above the equivalent of 1 million curies of cobalt-60, electron beams are more e...

  15. Electron irradiation effect on bubble formation and growth in a sodium borosilicate glass

    International Nuclear Information System (INIS)

    Chen, X.; Birtcher, R. C.; Donnelly, S. E.

    2000-01-01

    In this study, the authors studied simultaneous and intermittent electron irradiation effects on bubble growth in a simple sodium borosilicate glass during Xe ion implantation at 200 C. Simultaneous electron irradiation increases the average bubble size in the glass. This enhanced diffusion is also shown by the migration of Xe from bubbles into the matrix when the sample is irradiated by an electron beam after the Xe implantation

  16. Advanced Oxidation Treatment of Drinking Water and Wastewater Using High-energy Electron Beam Irradiation

    Directory of Open Access Journals (Sweden)

    Abbas Behjat

    2007-03-01

    Full Text Available Application of electron beam as a strong oxidation method for disinfection of drinking water and wastewater has been investigated. Drinking water samples were prepared from wells in rock zones in Yazd Province. Wastewater samples were collected from Yazd Wastewater Treatment Plant. Samples were irradiated by 10 MeV electron beam accelerator at Yazd Radiation Processing Center. The irradiation dose range varied from 0.5-5 kGy. Biological parameters and microbial agents such as aerobic mesophiles and coliforms including E. coli count before and after irradiation versus irradiation dose were obtained using MPN method. The data obtained from irradiated water and wastewater were compared with un-irradiated (control samples. The results showed a removal of 90% of all microorganisms at irradiation doses below 5 kGy, suggesting electron beam irradiation as an effective method for disinfection of wastewater.

  17. An AES Study of the Room Temperature Surface Conditioning of Technological Metal Surfaces by Electron Irradiation

    CERN Document Server

    Scheuerlein, C; Taborelli, M; Brown, A; Baker, M A

    2002-01-01

    The modifications to technological copper and niobium surfaces induced by 2.5 keV electron irradiation have been investigated in the context of the conditioning process occurring in particle accelerator ultra high vacuum systems. Changes in the elemental surface composition have been found using Scanning Auger Microscopy (SAM) by monitoring the carbon, oxygen and metal Auger peak intensities as a function of electron irradiation in the dose range 10-6 to 10-2 C mm-2. The surface analysis results are compared with electron dose dependent secondary electron and electron stimulated desorption yield measurements. Initially the electron irradiation causes a surface cleaning through electron stimulated desorption, in particular of hydrogen. During this period both the electron stimulated desorption and secondary electron yield decrease as a function of electron dose. When the electron dose exceeds 10-4 C mm-2 electron stimulated desorption yields are reduced by several orders of magnitude and the electron beam indu...

  18. Electronic emission and electron spin resonance of irradiated clothes: (cottons, synthetic clothes)

    International Nuclear Information System (INIS)

    El Ajouz Rima, H.

    1984-10-01

    This thesis is devoted to a new method of dosimetry applicable to accidental irradiations. It is based on the use of cotton and synthetic fabric clothes as detectors. It enables absorbed doses and body dose distributions to be estimated after an accidental irradiation. A bibliography on textile fibres used for clothing is presented in the first chapter: origin, structure, industrial treatments, effects of heat, light, ionizing radiations. In the second chapter, electronic emission generated by double stimulation (thermal and optic) is described. This phenomenon reveals changes in the surface state of cotton. Exo-emission was chosen because of its high sensitivity in dosimetry. The third chapter is devoted to the application of electron paramagnetic resonance to the dosimetry of irradiated fabrics. After a brief description of the spectrometer used, the results obtained with commercial cotton fabrics and with a special fabric realized by the Institut Textile de France are described some of these fabrics were subjected to special treatments either before or after irradiation. Synthetic fabrics (polyesters and polypropylene) have also been studied. (author)

  19. Structural changes and tribological performance of thermosetting polyimide induced by proton and electron irradiation

    International Nuclear Information System (INIS)

    Lv, Mei; Wang, Yanming; Wang, Qihua; Wang, Tingmei; Liang, Yongmin

    2015-01-01

    The structural changes and tribological performance of thermosetting polyimide were investigated by electron, proton or both combined irradiations at 25 keV in a ground-based simulation facility. Three forms of irradiations could lead to the formation of the carbonized layer on the polymer surface that could increase the hardness and adhesive force of the material. Proton irradiation induced more extensive changes in structure and friction behavior than electron irradiation by reason of the higher linear energy transfer value, and combined irradiation resulted in the largest impact, but which was less than the sum of the radiation effects of electron and proton. Moreover, the experimental results indicated that the changes in friction behavior are closely related with the carbonized layer, which was easily worn out in friction process and could introduce a shift from adhesion wear to three-body abrasive wear that reduced the wear rate and the friction coefficient. The friction process of irradiated samples could be divided into the initial stage and the steady stage. Three forms of irradiations all induced the high friction coefficient in the initial stage and the low friction coefficient in the steady stage, and the wear rate of the irradiated samples decreased in the order: electron irradiation>proton irradiation>combined irradiation. - Highlights: • Proton irradiation induced more extensive changes in structure and friction behavior than electron irradiation. • The effect of combined irradiation was less than that of the sum of electron and proton irradiation. • Three forms of irradiations all induced the high initial friction coefficient and the low steady-stage friction coefficient. • The initial friction stage means a fast-wearing adhesive process while the steady-state of the system is a three-body abrasion

  20. Influence of high energy electron irradiation and gamma irradiation on the osmotic resistance of human erythrocyte membranes

    International Nuclear Information System (INIS)

    Catana, D.; Hategan, Alina; Moraru, Rodica; Popescu, Alina; Morariu, V. V.

    1998-01-01

    The effects of 5 MeV electrons and of gamma irradiation at 0 deg. C on the osmotic fragility of human erythrocyte membranes are presented. Both electron and gamma radiation in the range 0-400 Gy induced no hemolysis indicating that the membrane modifications due to radiation interaction do not reach a critical point as to cause swelling of the cells and subsequent lysis. The osmotic stress experiments performed after irradiation showed that the gamma irradiated erythrocytes exhibited an almost similar sigmoidal behavior for all irradiation doses, whereas the electron irradiated samples showed a much larger increase in hemolysis degree and, in the case of a given electron dose (100 Gy), the hemolysis was found much smaller than for the control sample (a similar behavior of the erythrocytes was found in the case of microwave irradiation at temperatures under 0 deg. C). Our experimental data suggest that electron radiation and gamma radiation have different impacts on the erythrocyte membrane fluidity, involving, probably, the different rate of energy deposition in the samples and the direct interaction of electrons with the erythrocyte membranes. (authors)

  1. Application of electron beams irradiation in science and industry

    International Nuclear Information System (INIS)

    Hilmy, N.; Razzak, M.T.; Chosdu, R.; Soebianto, Y.S.

    1996-01-01

    The research and development of radiation technology in Indonesia is mainly conducted at the Center for Application of Isotopes and Radiation of the National Atomic Energy Agency (CAIR-BATAN). During the past 10 years, the center has gained a great progress in the development of gamma irradiation techniques for industrial processing, food preservation, health care products sterilization, and waste treatment. A low energy (300 keV, 50 mA) electron beam accelerator has been installed in cooperation with IAEA/UNDP as a training and demonstration facility for wood surface coating. In spite of the advantages of radiation curing, this technique is still unacceptable in the industries due to the uneconomical reasons and inferiority of the products. The research and development using this facility is also considered expensive, due to the high cost of the liquid nitrogen consumed by the accelerator. The medium energy (2 MeV, 10 mA) accelerator has been installed recently. This is a multipurpose irradiator provided with a belt conveyer, but also designed for wire and cable irradiation. The main technical parameters have been measured under different operating conditions during its commissioning, and the nominal dose measurement has been performed using alanine polyethylene, ethanol-chlorobenzene solution, and FWT-60 film dosimeters. Research and development of polymer cross-linking and shrinkable tubes have become the concern of the accelerator application. The radiation curable polyethylene compound for the cable insulation has been formulated with a characteristic of high voltage and heat resistant. Dosimetry of spices with 0.3-0.6 g/cm 3 density and health care products of 0.2-0.3 g/cm 3 density have been carried out for the promising food preservation and radiation sterilization, energy beam on micro-organism, and surface modification of some synthetic and natural polymers are also carried out. (J.P.N.)

  2. Silicon passivation study under low energy electron irradiation conditions

    International Nuclear Information System (INIS)

    Cluzel, R.

    2010-01-01

    Backside illuminated thinned CMOS (Complementary Metal Oxide Semiconductor) imaging system is a technology developed to increase the signal to noise ratio and the sensibility of such sensors. This configuration is adapted to the electrons detection from the energy range of [1 - 12 keV]. The impinging electron creates by multiplication several hundreds of secondary electrons close to the surface. A P ++ highly-doped passivation layer of the rear face is required to reduce the secondary electron surface recombination rate. Thanks to the potential barrier induced by the P ++ layer, the passivation layer increases the collected charges number and so the sensor collection gain. The goal of this study is to develop some experimental methods in order to determine the effect of six different passivation processes on the collection gain. Beforehand, the energy profile deposited by an incident electron is studied with the combination of Monte-Carlo simulations and some analytical calculations. The final collection gain model shows that the mirror effect from the passivation layer is a key factor at high energies whereas the passivation layer has to be as thin as possible at low energies. A first experimental setup which consists in irradiating P ++ /N large diodes allows to study the passivation process impacts on the surface recombinations. Thanks to a second setup based on a single event upset directly on thinned CMOS sensor, passivation techniques are discriminated in term of mirror effect and the implied spreading charges. The doping atoms activation laser annealing is turn out to be a multiplication gain inhomogeneity source impacting directly the matrix uniformity. (author)

  3. Rotational total skin electron irradiation with a linear accelerator

    Science.gov (United States)

    Evans, Michael D.C.; Devic, Slobodan; Parker, William; Freeman, Carolyn R.; Roberge, David; Podgorsak, Ervin B.

    2008-01-01

    The rotational total skin electron irradiation (RTSEI) technique at our institution has undergone several developments over the past few years. Replacement of the formerly used linear accelerator has prompted many modifications to the previous technique. With the current technique, the patient is treated with a single large field while standing on a rotating platform, at a source‐to‐surface distance of 380 cm. The electron field is produced by a Varian 21EX linear accelerator using the commercially available 6 MeV high dose rate total skin electron mode, along with a custom‐built flattening filter. Ionization chambers, radiochromic film, and MOSFET (metal oxide semiconductor field effect transistor) detectors have been used to determine the dosimetric properties of this technique. Measurements investigating the stationary beam properties, the effects of full rotation, and the dose distributions to a humanoid phantom are reported. The current treatment technique and dose regimen are also described. PACS numbers: 87.55.ne, 87.53.Hv, 87.53.Mr

  4. Hydrogel coating of RVNRL film by electron beam irradiation

    International Nuclear Information System (INIS)

    Chantara Thevy Ratnam; Khairul Zaman Hj, Mohd Dahlan; Fumio Yoshii; Keizo Makuuchi

    1996-01-01

    The tackiness properties of Radiation Vulcanized Natural Rubber Latex (RVNRL) film surfaces coated by various monomers have been investigated in order to understand the suitable hydrogels which reduce the tackiness of the film. In this context , different types of monomers namely, N-vinyl-2-pyrrolidone (NVP), N,N-dimethyl amino ethyl amide (DMAEA), acrylic acid (AAc), N-butyl acrylate (n-BA) and 2-hydroxyethyl methacrylate (HEMA) as well as monomer mixtures have been tried with varying degrees of success. It was found that coating the RVNRL with 80% HEMA/20% n-BA by irradiation at 80 kGy using low Energy Electron Beam gave remarkable reduction in surface tackiness of the RVNRL film. Several other attempts were made such as priming with acid and aluminum sulfate, mixing the aluminum sulfate into the monomer and dipping the partially wet RVNRL film into the monomer to enhance the wettability of he monomers with the film. Studies on surface topography revealed that the decrease in tackiness with coating is due to the increase of the surface roughness at 80 kGy, irradiation dose

  5. Demonstration plant of smoke treatment by electron beam irradiation

    International Nuclear Information System (INIS)

    Kawamura, Keita

    1989-01-01

    The acid rain caused by sulfur oxides and nitrogen oxides has become the large social problem as it damages forests, lakes and agricultural crops and also buildings in Europe and America. In such circumstances, concern has been expressed in various countries on the smoke treatment technology, EBA process, which removes the sulfur oxides and nitrogen oxides contained in smoke simultaneously by irradiating electron beam on the smoke which is exhausted from power station boilers and industrial boilers and mainly causes acid rain. The research and development of this technology were begun in 1971 based on the original idea of Ebara Corp., and from 1972, those were advanced as the joint research with Japan Atomic Energy Research Institute. Thereafter, by the joint research with the technical research association on prevention of nitrogen oxides in iron and steel industry, by ammonia addition and irradiation process, the desulfurization and denitration performance was heightened, and the byproduct was successfully captured as powder, in this way, the continuous dry treatment process was established. The demonstration test plant was constructed in a coal-firing power station in Indiana, USA, and the trial operation was carried out from 1985 for two years. (K.I.)

  6. Electron spin resonance study of radicals in irradiated polyethylene

    International Nuclear Information System (INIS)

    Fujimura, Takashi

    1979-02-01

    In order to elucidate radiation effect in polyethylene, the nature and behavior of radicals produced in polyethylene and the model compound of polyethylene irradiated at 77 0 K were studied by using electron spin resonance. The structure of radical pairs, which are composed of two radicals produced very closely each other, was investigated in drawn polyethylene and the single crystal of n-eicosane. The radical pairs of intrachain type and interchain type were found in polyethylene and n-eicosane respectively. It was suggested that these two types of radical pairs are the precursors of double bonds and crosslinks respectively. The thermal decay reactions of radicals themselves produced in irradiated polyethylene were investigated. It was made clear that the short range distances between two radicals play an important role in the decay reaction of alkyl radicals at low temperatures. The trapping regions of radicals were studied and it was clarified that allyl radicals, which are produced by the reaction of alkyl radicals with double bonds, are trapped both in the crystalline and non-crystalline regions. (author)

  7. Electron beam irradiation and zeolites adsorption applied to dyeing effluents

    International Nuclear Information System (INIS)

    Higa, Marcela C.; Fungaro, Denise A.; Somessari, Elizabeth S.R.; Magdalena, Carina P.; Grosche, Lucas C.; NNeto, Antonio C.; Borrely, Sueli I.

    2007-01-01

    Wastewater generated from the textile industries contain large amount of azo dyes and many of them present low biodegradability capability. Today several countries are facing with evidences that water pollution is related to toxicity, mutagenicity and carcinogenic nature. Once reactive dyes are commercial products they will be discharged to the waterways and rivers causing ecological damages and health problems. The aim of this paper was to consider the potential of two techniques for colour and toxicity removal: ionizing radiation and adsorption by zeolites synthesized from fly ash. Real effluents from chemical and textile industries (hardly coloured) were submitted to radiation and adsorption using zeolites. It was necessary to dilute some effluents prior the treatments in order to get any success. When electrons irradiation was performed radiation doses applied were from 0.5 kGy up to 20 kGy. This radiation process accounted for a partial decolouring as higher doses were implemented. Coal fly ashes were used as starting material for zeolite synthesis by means of hydrothermal treatment with alkaline medium. The adsorption was performed by batch experiments. It was obtained about 77% - 90% color removal from dye wastewater after 24h of contact time with two types of zeolite. The irradiation accounted for 72% of the initial toxicity. The ionizing radiation and adsorption by zeolites synthesized from fly ash can be used as an alternative for the treatment of aqueous waste containing dyes. (author)

  8. In situ transmission electron microscope studies of ion irradiation-induced and irradiation-enhanced phase changes

    International Nuclear Information System (INIS)

    Allen, C.W.

    1992-01-01

    Motivated at least initially by materials needs for nuclear reactor development, extensive irradiation effects studies employing transmission electron microscopes (TEM) have been performed for several decades, involving irradiation-induced and irradiation-enhanced microstructural changes, including phase transformations such as precipitation, dissolution, crystallization, amorphization, and order-disorder phenomena. From the introduction of commercial high voltage electron microscopes (HVEM) in the mid-1960s, studies of electron irradiation effects have constituted a major aspect of HVEM application in materials science. For irradiation effects studies two additional developments have had particularly significant impact; the development of TEM specimen holder sin which specimen temperature can be controlled in the range 10-2200 K and the interfacing of ion accelerators which allows in situ TEM studies of irradiation effects and the ion beam modification of materials within this broad temperature range. This paper treats several aspects of in situ studies of electron and ion beam-induced and enhanced phase changes and presents two case studies involving in situ experiments performed in an HVEM to illustrate the strategies of such an approach of the materials research of irradiation effects

  9. Origin of the main deep electron trap in electron irradiated InP

    International Nuclear Information System (INIS)

    Sibille, A.

    1986-01-01

    The electrical activity and annealing behavior of the main electron trap in electron irradiated InP p + n junctions has been investigated. A very marked depth dependence of the annealing rate has been found. Moreover, this center apparently acts as if it were a deep donor, leading to an increase of carrier concentration on the n side. All these results are coherently interpreted with a model in terms of radiation defect D(P) (phosphorus interstitial or vacancy), residual shallow acceptor complexing, the final annealing resulting from a dissociation of the complex followed by a diffusion and either recapture or annihilation of D(P)

  10. Interpretation of recovery stage III in gold. [Electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Seeger, A.; Frank, W. (Max-Planck-Institut fuer Metallforschung, Stuttgart (Germany, F.R.). Inst. fuer Physik; Stuttgart Univ. (Germany, F.R.). Inst. fuer Theoretische und Angewandte Physik)

    1983-05-01

    The paper compares a recent investigation of Stage-III recovery on electron-irradiated gold by Sonnenberg and Dedek with earlier work on cold-worked or quenched gold. The experimental results of Sonnenberg and Dedek are found to be in excellent agreement with those of Schuele, Seeger, Schumacher, and King, who showed that in Au Stage III is due to the migration of an elementary intrinsic point defect with migration enthalpy Hsup(III) = (0.71 +- 0.02)eV. Since the monovacancy migration enthalpy Hsub(IVsup(M)) = (0.83 +- 0.02)eV obtained by Schuele et al. has been confirmed by other workers and independent techniques, it is concluded that Hsup(III) represents the migration enthalpy of isolated self-interstitials.

  11. Issues for Bringing Electron Beam Irradiators On-Line

    International Nuclear Information System (INIS)

    Kaye, R.J.; Turman, B.N.

    1999-01-01

    Irradiation of red meat and poultry has been approved by the U.S. FDA, and the U.S. Department of Agriculture's rule for processing red meat is out for comment. Looking beyond the current issues of packaging materials, labeling, and consumer acceptance, this paper reviews the next step of implementation and how to remove, or at least reduce, the barriers to utilization. Polls of the user community identified their requirements for electron beam or x-ray processing of meat or poultry and their concerns about implementation for on-line processing. These needs and issues are compared to the capabilities of the accelerator industry. The critical issues of beam utilization and dose uniformity, factors affecting floor space requirements, and treatment costs are examined

  12. Retting effect of kenaf bast fiber by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hye Kyoung; Kangm Hyo Kyoung; Jeun, Joon Pyo; Kang, Phil Hyun [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2010-06-15

    Kenaf (Hibiscus cannabinus) retting were separated from a kenaf bast fiber by a combination of Electron beam irradiation (EBI) and NaOH solution treatment. The methods were based on a 6% NaOH solution treatment after various doses of EBI. FT-IR spectroscopy demonstrated that the content of lignin and hemicellulose in the retted kenaf fibers decreased as the EBI dose increased. Specifically, the lignin in the retted kenaf fiber treated with 300 kGy of EBI was almost completely removed. The morphology of retted kenaf fibers were characterized by SEM image, and the studies showed that the fibrillated degree of retted kenaf fibers treated with various EBI doses and was increased as EBI dose increased. The retted kenaf fibers treated with the EBI at 300 kGy was uniformly fibrillated with 10 {approx} 30 {mu}m diameters.

  13. Retting effect of kenaf bast fiber by electron beam irradiation

    International Nuclear Information System (INIS)

    Shin, Hye Kyoung; Kangm Hyo Kyoung; Jeun, Joon Pyo; Kang, Phil Hyun

    2010-01-01

    Kenaf (Hibiscus cannabinus) retting were separated from a kenaf bast fiber by a combination of Electron beam irradiation (EBI) and NaOH solution treatment. The methods were based on a 6% NaOH solution treatment after various doses of EBI. FT-IR spectroscopy demonstrated that the content of lignin and hemicellulose in the retted kenaf fibers decreased as the EBI dose increased. Specifically, the lignin in the retted kenaf fiber treated with 300 kGy of EBI was almost completely removed. The morphology of retted kenaf fibers were characterized by SEM image, and the studies showed that the fibrillated degree of retted kenaf fibers treated with various EBI doses and was increased as EBI dose increased. The retted kenaf fibers treated with the EBI at 300 kGy was uniformly fibrillated with 10 ∼ 30 μm diameters

  14. Electron beam irradiation experiments of monoblock divertor mock-up

    International Nuclear Information System (INIS)

    Satoh, Kazuyoshi; Akiba, Masato; Araki, Masanori; Suzuki, Satoshi; Yokoyama, Kenji; Smid, I.; Cardella, A.; Duwe, R.; Di Pietro, E.

    1993-03-01

    It is one of the key issues for ITER to develop the divertor plate. Electron beam irradiation tests were carried out on a NET divertor mock-up using JEBIS at JAERI under a collaboration between The NET team, JAERI and KFA Juelich. Screening tests (maximum heat flux of 23 MW/m 2 ) and thermal cycling tests (18 MW/m 2 , 30s, 1000cycle) were carried out. As a result of the screening tests, the erosion caused by sublimation of C/C was observed on the surface of armor tile. No serious damage such as cracks or detachments, however, were found. As a result of the thermal cycling tests, no major damage was detected on the C/C surface. However cooling time constant of the divertor mock-up increased over 600cycle. Therefore it implies that some defects would occur at the brazing interface of the divertor mock-up. (author)

  15. 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.

  16. Issues for Bringing Electron Beam Irradiators On-Line

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, R.J.; Turman, B.N.

    1999-04-20

    Irradiation of red meat and poultry has been approved by the U.S. FDA, and the U.S. Department of Agriculture's rule for processing red meat is out for comment. Looking beyond the current issues of packaging materials, labeling, and consumer acceptance, this paper reviews the next step of implementation and how to remove, or at least reduce, the barriers to utilization. Polls of the user community identified their requirements for electron beam or x-ray processing of meat or poultry and their concerns about implementation for on-line processing. These needs and issues are compared to the capabilities of the accelerator industry. The critical issues of beam utilization and dose uniformity, factors affecting floor space requirements, and treatment costs are examined.

  17. Investigation of carrier removal in electron irradiated silicon diodes

    International Nuclear Information System (INIS)

    Taylor, S.J.; Yamaguchi, M.; Matsuda, S.; Hisamatsu, T.; Kawasaki, O.

    1997-01-01

    We present a detailed study of n + p p + silicon diodes irradiated with fluences of 1 MeV electrons high enough to cause device failure due to majority carrier removal. Capacitance voltage (C V) measurements were used to monitor the change in the carrier concentration of the base of the device as a function of radiation fluence. These were compared to the defect spectra in the same region obtained by deep level transient spectroscopy, and to the current voltage characteristics of the device, both before and after annealing. We observed the expected deep levels with activation energies of 0.18 and 0.36 eV, but the C endash V results imply that other trap levels must play a more important role in the carrier removal process. copyright 1997 American Institute of Physics

  18. Surface decontamination of cheddar cheese by electron-beam irradiation

    International Nuclear Information System (INIS)

    Shamsuzzaman, K.

    1991-01-01

    Cheddar cheese samples inoculated with two different levels of Penicillium cyclopium or Aspergillus ochraceus spores were vacuum-packed and irradiated at various doses up to 3.5 kGy with electrons from a 10-MeV linear accelerator. Unirradiated cheese showed visible mold growth in 8-25 d at 10 degrees C, and 7-12 d at 15 degrees C, depending on species and spore concentration. Only marginal extension of shelf life at 15 degrees C was achieved with cheese inoculated with 10 2 cfu per sample of either of the mold spores, followed by irradiation at 0.21 or 0.52 kGy. However, at these doses the average shelf life at 10 degrees C was extended by 41.5 and 50.5 d respectively when the inoculum was A. ochraceus. When the inoculum level was increased tenfold, irradiation at 1.2 and 3.5 kGy extended the average shelf life of cheese containing P. cyclopium by 44.5 and >262 d respectively at 10 degrees C, and by 3 and >166 d respectively at 15 degrees C. The shelf life of samples containing A. ochraceus and irradiated at 1.2 or 3.5 kGy was extended by at least 255.5 d at 10 degrees C and at least 160 d at 15 degrees C. The results clearly showed that low radiation doses are effective in the mold decontamination of cheese. The results also suggest that P. cyclopium in Cheddar cheese is more radiation-resistant than A. ochraceus. This was supported by determination of radiation survival curves for the two species incorporated into Cheddar cheese: D 10 values for P. cyclopium and A. ochraceus were found to be 0.40 and 0.21 kGy respectively. The radiation sensitivity of the two organisms was found not to vary with pH in the pH range 5.0-6.2

  19. Immediate remediation of heavy metal (Cr(VI)) contaminated soil by high energy electron beam irradiation

    International Nuclear Information System (INIS)

    Zhang, Jing; Zhang, Guilong; Cai, Dongqing; Wu, Zhengyan

    2015-01-01

    Highlights: • An immediate remediation method for Cr(VI) contaminated soil (CCS) was developed. • High energy electron beam (HEEB) irradiation could reduce Cr(VI) in CCS to Cr(III). • This effect was attributed to electrons, hydrated electrons, and reductive radicals. • This remediation method was effective, environmentally friendly, and low-cost. - Abstract: This work developed an immediate and high-performance remediation method for Cr(VI) contaminated soil (CCS) using high energy electron beam (HEEB) irradiation. The result indicated that, compared with γ-ray irradiation, HEEB irradiation displayed a significant reduction efficiency on Cr(VI) in CCS to Cr(III) with substantially lower toxicity, which was mainly attributed to the reduction effects of electrons, hydrated electrons, and reductive radicals generated in the irradiation process of HEEB. This work could provide a one-step and effective method for the remediation of heavy metal contaminated soil (HMCS)

  20. Immediate remediation of heavy metal (Cr(VI)) contaminated soil by high energy electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jing; Zhang, Guilong [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Cai, Dongqing, E-mail: dqcai@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Wu, Zhengyan, E-mail: zywu@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China)

    2015-03-21

    Highlights: • An immediate remediation method for Cr(VI) contaminated soil (CCS) was developed. • High energy electron beam (HEEB) irradiation could reduce Cr(VI) in CCS to Cr(III). • This effect was attributed to electrons, hydrated electrons, and reductive radicals. • This remediation method was effective, environmentally friendly, and low-cost. - Abstract: This work developed an immediate and high-performance remediation method for Cr(VI) contaminated soil (CCS) using high energy electron beam (HEEB) irradiation. The result indicated that, compared with γ-ray irradiation, HEEB irradiation displayed a significant reduction efficiency on Cr(VI) in CCS to Cr(III) with substantially lower toxicity, which was mainly attributed to the reduction effects of electrons, hydrated electrons, and reductive radicals generated in the irradiation process of HEEB. This work could provide a one-step and effective method for the remediation of heavy metal contaminated soil (HMCS)

  1. Preliminary examination of induced radioactivity in pepper by 10 MeV electron irradiation

    International Nuclear Information System (INIS)

    Katayama, Tadashi; Furuta, Masakazu; Sibata, Setsuko; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Toratani, Hirokazu; Takeda, Atsuhiko.

    1991-01-01

    β-ray measurement was performed on 10 MeV electron-irradiated black pepper and white pepper with liquid scintillation counter in order to reconfirm the wholesomeness of irradiated foods and present unambiguous data to general consumers concerning about the induced radioactivity in the irradiated foods. In irradiated black pepper no radioactivity other than from natural source, un-irradiated one, was detected. But in irradiated white pepper, it was suggested that induced radioactivity might be detected if the detection method was more improved. (author)

  2. Compositional changes in industrial hemp biomass (Cannabis sativa L.) induced by electron beam irradiation Pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Yong Joo [Department of Biobased Materials, College of Agriculture and Life Science, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Shin, Soo-Jeong [Department of Wood and Paper Science, College of Agriculture and Life Science, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)

    2011-07-15

    The effects of electron beam irradiation on chemical decomposition of industrial hemp biomass were evaluated at doses of 150, 300, and 450 kGy. The quantity of decomposed components was indirectly estimated by measuring changes in alkaline extraction. The more severe degradation of structural components induced by higher irradiation doses resulted in larger amounts of alkaline extract. Carbohydrate compositional analysis using {sup 1}H-NMR spectroscopy was applied to quantitatively investigate changes in the polysaccharides of the industrial hemp. The xylose peak intensity in the NMR spectra decreased with increasing electron irradiation dose, indicating that xylan was more sensitive to electron beam irradiation than cellulose. -- Highlights: {yields} The more severe degradation of structural components induced by higher irradiation. {yields} Carbohydrate analysis was applied to quantitatively investigate changes in the industrial hemp. {yields} Xylan was more sensitive to electron beam irradiation than cellulose.

  3. Compositional changes in industrial hemp biomass (Cannabis sativa L.) induced by electron beam irradiation Pretreatment

    International Nuclear Information System (INIS)

    Sung, Yong Joo; Shin, Soo-Jeong

    2011-01-01

    The effects of electron beam irradiation on chemical decomposition of industrial hemp biomass were evaluated at doses of 150, 300, and 450 kGy. The quantity of decomposed components was indirectly estimated by measuring changes in alkaline extraction. The more severe degradation of structural components induced by higher irradiation doses resulted in larger amounts of alkaline extract. Carbohydrate compositional analysis using 1 H-NMR spectroscopy was applied to quantitatively investigate changes in the polysaccharides of the industrial hemp. The xylose peak intensity in the NMR spectra decreased with increasing electron irradiation dose, indicating that xylan was more sensitive to electron beam irradiation than cellulose. -- Highlights: → The more severe degradation of structural components induced by higher irradiation. → Carbohydrate analysis was applied to quantitatively investigate changes in the industrial hemp. → Xylan was more sensitive to electron beam irradiation than cellulose.

  4. Microbial growth and sensory quality of dried potato slices irradiated by electrons

    International Nuclear Information System (INIS)

    Kim, Hyun-Jin; Song, Hyeon-Jeong; Song, Kyung-Bin

    2011-01-01

    Electron beam irradiation was applied to secure the microbial safety of dried purple sweet potato. After purple sweet potato slices had been dehydrated with 20% (w/w) maltodextrin solution, the samples were irradiated at doses 2, 4, 6, 8, and 10 kGy and then stored at 20 o C for 60 days. Microbiological data indicated that the populations of total aerobic bacteria and of yeast and molds significantly decreased with increase in irradiation dosage. Specifically, microbial load was reduced by about three log cycles at 6 kGy compared to those of the control. Based on the color measurement of the potato slices, electron beam irradiation treatment did not affect the color quality. Sensory evaluation results also showed that electron beam irradiation did not affect overall sensory scores during storage. These results suggest that electron beam irradiation could be useful for improving microbial safety without impairing the quality of the potato slices during storage.

  5. Enhanced thermal stability of a polymer solar cell blend induced by electron beam irradiation in the transmission electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Bäcke, Olof, E-mail: obacke@chalmers.se [Department of Applied Physics, Chalmers University of Technology, 41296 Göteborg (Sweden); Lindqvist, Camilla; Diaz de Zerio Mendaza, Amaia [Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg (Sweden); Gustafsson, Stefan [Department of Applied Physics, Chalmers University of Technology, 41296 Göteborg (Sweden); Wang, Ergang; Andersson, Mats R.; Müller, Christian [Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg (Sweden); Kristiansen, Per Magnus [Institute of Polymer Nanotechnology (INKA), FHNW University of Applied Science and Arts Northwestern Switzerland, 5210 Windisch (Switzerland); Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, 5232 Villigen (Switzerland); Olsson, Eva, E-mail: eva.olsson@chalmers.se [Department of Applied Physics, Chalmers University of Technology, 41296 Göteborg (Sweden)

    2017-05-15

    We show by in situ microscopy that the effects of electron beam irradiation during transmission electron microscopy can be used to lock microstructural features and enhance the structural thermal stability of a nanostructured polymer:fullerene blend. Polymer:fullerene bulk-heterojunction thin films show great promise for use as active layers in organic solar cells but their low thermal stability is a hindrance. Lack of thermal stability complicates manufacturing and influences the lifetime of devices. To investigate how electron irradiation affects the thermal stability of polymer:fullerene films, a model bulk-heterojunction film based on a thiophene-quinoxaline copolymer and a fullerene derivative was heat-treated in-situ in a transmission electron microscope. In areas of the film that exposed to the electron beam the nanostructure of the film remained stable, while the nanostructure in areas not exposed to the electron beam underwent large phase separation and nucleation of fullerene crystals. UV–vis spectroscopy shows that the polymer:fullerene films are stable for electron doses up to 2000 kGy. - Highlights: • Thermal stability of a polymer: fullerne blend is increased using electron irradiation. • Using in-situ transmission electron microscopy the nanostructure is studied. • Electron irradiation stops phase separation between the polymer and fullerene. • Electron irradiation quenches the formation and nucleation of fullerene crystals.

  6. Influence of electron irradiation on the structural and thermal properties of silk fibroin films

    Energy Technology Data Exchange (ETDEWEB)

    Asha, S.; Sangappa,; Sanjeev, Ganesh, E-mail: ganeshanjeev@rediffmail.com [Department of Studies in Physics, Mangalore University, Mangalagangotri, Mangalore - 574 199 (India)

    2015-06-24

    Radiation-induced changes in Bombyx mori silk fibroin (SF) films under electron irradiation were investigated and correlated with dose. SF films were irradiated in air at room temperature using 8 MeV electron beam in the range 0-150 kGy. Various properties of the irradiated SF films were studied using X-ray diffraction (XRD), Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Electron irradiation was found to induce changes in the physical and thermal properties, depending on the radiation dose.

  7. Electron beam irradiation and adsorption as possibilities for wastewater reuse

    International Nuclear Information System (INIS)

    Borrely, Sueli I.; Higa, Marcela C.; Pinheiro, Alessandro; Morais, Aline V.; Fungaro, Denise A.

    2013-01-01

    The importance of water for life and for the industrial processes is forcing the development of combined technologies for wastewater improvement. The limitations of biological treatment for reducing micro-pollutants and the constant introduction of different chemical into environment make Ionizing Radiation a more interesting technique for pollutants abatement. Electron Accelerators are the main radiation source for cleaning waters purpose. Remazol Orange and Black B were decomposed by Electron Beam Irradiation. Another research consisted in reuse of burnt coal for cleaning wastewater and the Orange and Red dyes were adsorbed onto zeolitic material. Both color and toxicity were the main parameters to evaluate the efficacy of the process and also the recommended criteria which allow further industrial reuse. Real effluents were also treated by both technologies in batch scale. The radiation dose suggested for real effluents varied from 2.5kGy up to 5kGy. The characteristics of obtained zeolite will be presented. The removal of color and toxicity was enough to allow the industrial reuse of those products (wastewater). (author)

  8. A simultaneous electron energy and dosimeter calibration method for an electron beam irradiator

    International Nuclear Information System (INIS)

    Tanaka, R.; Sunaga, H.; Kojima, T.

    1991-01-01

    In radiation processing using electron accelerators, the reproducibility of absorbed dose in the product depends not only on the variation of beam current and conveyor speed, but also on variations of other accelerator parameters. This requires routine monitoring of the beam current and the scan width, and also requires periodical calibration of routine dosimeters usually in the shape of film, electron energy, and other radiation field parameters. The electron energy calibration is important especially for food processing. The dose calibration method using partial absorption calorimeters provides only information about absorbed dose. Measurement of average electron current density provides basic information about the radiation field formed by the beam scanning and scattering at the beam window, though it does not allow direct dose calibration. The total absorption calorimeter with a thick absorber allows dose and dosimeter calibration, if the depth profile of relative dose in a reference absorber is given experimentally. It also allows accurate calibration of the average electron energy at the surface of the calorimeter core, if electron fluence received by the calorimeter is measured at the same time. This means that both electron energy and dosimeters can be simultaneously calibrated by irradiation of a combined system including the calorimeter, the detector of the electron current density meter, and a thick reference absorber for depth profile measurement of relative dose. We have developed a simple and multifunctional system using the combined calibration method for 5 MeV electron beams. The paper describes a simultaneous calibration method for electron energy and film dosimeters, and describes the electron current density meter, the total absorption calorimeter, and the characteristics of this method. (author). 13 refs, 7 figs, 3 tabs

  9. Study on the viability of peach and apple pollen treated with gamma rays 60Co

    International Nuclear Information System (INIS)

    Filev, K.; Angelov, A.

    1976-01-01

    Pollen from Marygold peach and from Golden Delicious apple varieties was treated with gamma-rays at rates of 0.5, 1.5, 10.0, 50.0, 100, 200, 300, 400 and 500 kR, the irradiation intensity being 1350 r/min. Results point to a different influence of gamma-rays irradiation on the pollen germination. Apple pollen proved more radiosensitive. Least dose of o.5 kR exerted a stimulative effect in the pollen germination. As the irradiation dose rcse, the germination percentage declined. Doses of over 400 kR destroyed completely pollen viability in both fruit species. A linear semi-logarithmical dependence was ascertained between the irradiation rate and pollen germination. 5 and 10 kR proved most suitable for the purposes of the experimental mutagenesis at peach and apple pollen irradiation. (author)

  10. Void formation in pure aluminium irradiated with high-energetic electron beams and gamma-quanta

    DEFF Research Database (Denmark)

    Gan, V. V.; Ozhigou, L. S.; Yamnitsky, V. A.

    1983-01-01

    The spatial distribution of displaced atoms and helium atoms and also the spectra of damaging energies of primary displaced atoms in a thick aluminium target irradiated with electrons of 225 MeV energy were calculated. Pure aluminium (99.9999%) irradiated up to 0.04 dose was studied by electron...

  11. Positron annihilation and electron spin resonance studies of defects in electron-irradiated 3C-SiC

    International Nuclear Information System (INIS)

    Itoh, Hisayoshi; Yoshikawa, Masahito; Tanigawa, Shoichiro; Nashiyama, Isamu; Misawa, Shunji; Okumura, Hajime; Yoshida, Sadafumi.

    1992-01-01

    Defects induced by 1 MeV electron-irradiation in cubic silicon carbide (3C-SiC) epitaxially grown by chemical vapor deposition have been studied with positron annihilation and electron spin resonance (ESR). Doppler broadened energy spectra of annihilation γ-rays obtained by using variable-energy positron beams showed the formation of vacancy-type defects in 3C-SiC by the electron-irradiation. An ESR spectrum labeled Tl, which has an isotropic g-value of 2.0029 ± 0.001, was observed in electron-irradiated 3C-SiC. The Tl spectrum is interpreted by hyperfine interactions of paramagnetic electrons with 13 C at four carbon sites and 29 Si at twelve silicon sites, indicating that the Tl center arises from a point defect at a silicon site. Both the results can be accounted for by the introduction of isolated Si vacancies by the irradiation. (author)

  12. Simultaneous electron-proton irradiation of crucible grown and float-zone silicon solar cells

    International Nuclear Information System (INIS)

    Bernard, J.

    1974-01-01

    The realisation of an irradiation chamber which permits simultaneous irradiations by electrons, protons, photons and in-situ measurements of solar cells main parameters (diffusion length, I.V. characteristics) is described. Results obtained on 20 solar cells n/p 10Ωcm made in silicon pulled crystals and 20 solar cells n/p 10Ωcm made in silicon float-zone simultaneously irradiated with electrons and photons are given [fr

  13. Study of γ-irradiated lithographic polymers by electron spin resonance and electron nuclear double resonance

    International Nuclear Information System (INIS)

    Schlick, S.; Kevan, L.

    1982-01-01

    The room temperature gamma irradiation degradation of the lithographic polymers, poly(methylmethacrylate) (PMMA), poly(methyl-α-chloroacrylate) (PMCA), poly(methyl-α-fluoroacrylate) (PMFA), and poly(methylacrylonitrile) (PMCN), have been studied by electron spin resonance and electron nuclear double resonance (ENDOR) to assess their molecular degradation processes of relevance to electron beam lithography. Two classes of radicals are found, chain radicals and chain scission radicals. PMMA and PMCA mainly form chain scission radicals consistent with degradation while for PMCN the resolution is poorer, and this is only probable. PMFA forms mainly chain radicals consistent with predominant crosslinking. The total radical yield is greatest in PMCA and PMCN. ENDOR is used to assess the compactness of the radiation degradation region for PMMA and PMCA and hence the potential resolution of the resist; this appears to be about the same for these methacrylate polymers

  14. Low-energy electron irradiation induced top-surface nanocrystallization of amorphous carbon film

    Science.gov (United States)

    Chen, Cheng; Fan, Xue; Diao, Dongfeng

    2016-10-01

    We report a low-energy electron irradiation method to nanocrystallize the top-surface of amorphous carbon film in electron cyclotron resonance plasma system. The nanostructure evolution of the carbon film as a function of electron irradiation density and time was examined by transmission electron microscope (TEM) and Raman spectroscopy. The results showed that the electron irradiation gave rise to the formation of sp2 nanocrystallites in the film top-surface within 4 nm thickness. The formation of sp2 nanocrystallite was ascribed to the inelastic electron scattering in the top-surface of carbon film. The frictional property of low-energy electron irradiated film was measured by a pin-on-disk tribometer. The sp2 nanocrystallized top-surface induced a lower friction coefficient than that of the original pure amorphous film. This method enables a convenient nanocrystallization of amorphous surface.

  15. Effects of keV electron irradiation on the avalanche-electron generation rates of three donors on oxidized silicon

    International Nuclear Information System (INIS)

    Sah, C.; Sun, J.Y.; Tzou, J.J.

    1983-01-01

    After keV electron beam irradiation of oxidized silicon, the avalanche-electron-injection generation rates and densities of the bulk compensating donor, the interface states, and the turnaround trap all increase. Heating at 200 0 C can anneal out these three donor-like traps, however, it cannot restore the generation rates back to their original and lower pre-keV electron irradiation values. The experimental results also indicate that all three traps may be related to the same mobile impurity species whose bonds are loosened by the keV electrons and then broken or released by the avalanche injected electrons

  16. Electron arc irradiation of the postmastectomy chest wall: clinical results

    Energy Technology Data Exchange (ETDEWEB)

    Gaffney, David K; Prows, Janalyn; Leavitt, Dennis; Egger, Marlene J; Morgan, John G; Stewart, J Robert

    1995-07-01

    Purpose/Objective: Since 1980 electron arc irradiation of the postmastectomy chest wall has been the preferred technique for patients with advanced breast cancer at the our institution. Here we report the results of this technique in 150 consecutive patients from 1980 to 1994. Materials and Methods: Thoracic computerized tomography was used to determine internal mammary lymph node depth and chest wall thickness, and for computerized dosimetry calculations in all patients. Total doses of 45-50 Gy in 5 to 5 (1(2)) weeks were delivered to the chest wall and internal mammary lymph nodes via electron arc and, in most cases, supraclavicular and axillary nodes were treated with a matching photon field. Patients were assessed for acute and late radiation changes, local and distant control of disease, and survival. The 10 most recently treated patients were censored for disease progression, survival, and late effects calculations, thus giving a mean follow up of 49 months and a median of 33 months. All patients had advanced disease: T stages 1, 2, 3, and 4 represented 21%, 39%, 21% and 19% of the study population, with a mean number of positive axillary lymph nodes of 6.5 (0-29). Analysis was performed according to adjuvant status (no residual disease, n = 90), residual disease (positive margin, n = 15, and primary radiation, n = 2), or recurrent disease (n = 33). Results: Acute radiation reactions were generally mild and self limiting. 27% of patients developed moist desquamation, and 32% had brisk erythema. Actuarial 5 year local control, freedom from distant failure and overall survival was 91%, 64%, and 67% in the adjuvant group; 84%, 50%, and 53% in the residual disease group; and 63%, 34%, and 30% in the recurrent disease group, respectively. In univariate cox regressions, the number of positive lymph nodes was predictive for local failure in the adjuvant group (p<0.037). Chronic complications were minimal with 10% of patients having arm edema, 15% hyperpigmentation

  17. Corrosion of electron-irradiated Zr-2.5Nb and Zircaloy-2

    Energy Technology Data Exchange (ETDEWEB)

    Woo, O.-T.; McDougall, G.M.; Hutcheon, R.M.; Urbanic, V.F.; Griffiths, M.; Coleman, C.E

    2000-07-01

    We used 10-MeV electrons to rapidly produce radiation damage in zirconium alloys, investigated whether electrons produced the same microstructural changes as neutrons, then performed post-irradiation corrosion tests to determine whether electron-irradiated materials displayed similar corrosion behavior to neutron-irradiated materials. Two irradiations were completed using 10-MeV electrons with the beam normal to thin disks of material of 4 diameter slightly larger than the beam. The beam distribution. and disk cooling were designed to produce radial temperature and dose distributions having maxima at the disk center. A high-temperature irradiation was performed on annealed Zr-2.5Nb disks, achieving a central dose of 1.3 dpa and at a central temperature of {approx}450 deg C. After irradiation, the samples contained needle-like {beta}-Nb precipitates in the {alpha}-Zr matrix similar to those produced by neutrons. A low-temperature irradiation was performed on half-moon disks of Zr-2.5Nb and Zircaloy-2 pressure tube materials at 310 deg C central temperature and 1.3-dpa central dose. Dislocation loops were observed, again similar to those produced in neutron-irradiated materials. Some of the high-temperature electron-irradiated disks were exposed to 300 deg C moist air (saturated with D{sub 2}O), and in separate tests, high- and low-temperature irradiated disks were corroded in 300 deg C D{sub 2}0 (11.0 pD at room temperature) in an autoclave. Measurements of oxide thickness by Fourier Transform Infrared Reflectance (FTIR) spectroscopy showed that electron irradiation reduced the corrosion rate of Zr-2.5Nb compared with that of unirradiated material, as observed for neutron irradiation. For exposures to moist air and to D{sub 2}O, the theoretical deuterium uptakes for the electron-irradiated materials were, respectively, about 4 times and 1.5 to 2 times those for the unirradiated materials. This is also in good agreement with results for neutron-irradiated pressure

  18. Corrosion of electron-irradiated Zr-2.5Nb and Zircaloy-2

    International Nuclear Information System (INIS)

    Woo, O.-T.; McDougall, G.M.; Hutcheon, R.M.; Urbanic, V.F.; Griffiths, M.; Coleman, C.E.

    2000-01-01

    We used 10-MeV electrons to rapidly produce radiation damage in zirconium alloys, investigated whether electrons produced the same microstructural changes as neutrons, then performed post-irradiation corrosion tests to determine whether electron-irradiated materials displayed similar corrosion behavior to neutron-irradiated materials. Two irradiations were completed using 10-MeV electrons with the beam normal to thin disks of material of 4 diameter slightly larger than the beam. The beam distribution. and disk cooling were designed to produce radial temperature and dose distributions having maxima at the disk center. A high-temperature irradiation was performed on annealed Zr-2.5Nb disks, achieving a central dose of 1.3 dpa and at a central temperature of ∼450 deg C. After irradiation, the samples contained needle-like β-Nb precipitates in the α-Zr matrix similar to those produced by neutrons. A low-temperature irradiation was performed on half-moon disks of Zr-2.5Nb and Zircaloy-2 pressure tube materials at 310 deg C central temperature and 1.3-dpa central dose. Dislocation loops were observed, again similar to those produced in neutron-irradiated materials. Some of the high-temperature electron-irradiated disks were exposed to 300 deg C moist air (saturated with D 2 O), and in separate tests, high- and low-temperature irradiated disks were corroded in 300 deg C D 2 0 (11.0 pD at room temperature) in an autoclave. Measurements of oxide thickness by Fourier Transform Infrared Reflectance (FTIR) spectroscopy showed that electron irradiation reduced the corrosion rate of Zr-2.5Nb compared with that of unirradiated material, as observed for neutron irradiation. For exposures to moist air and to D 2 O, the theoretical deuterium uptakes for the electron-irradiated materials were, respectively, about 4 times and 1.5 to 2 times those for the unirradiated materials. This is also in good agreement with results for neutron-irradiated pressure tube materials. Thus, 10-Me

  19. Improved calculation of displacements per atom cross section in solids by gamma and electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Piñera, Ibrahin, E-mail: ipinera@ceaden.edu.cu [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear, CEADEN, 30 St. 502, Playa 11300, Havana (Cuba); Cruz, Carlos M.; Leyva, Antonio; Abreu, Yamiel; Cabal, Ana E. [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear, CEADEN, 30 St. 502, Playa 11300, Havana (Cuba); Espen, Piet Van; Remortel, Nick Van [University of Antwerp, CGB, Groenenborgerlaan 171, 2020 Antwerpen (Belgium)

    2014-11-15

    Highlights: • We present a calculation procedure for dpa cross section in solids under irradiation. • Improvement about 10–90% for the gamma irradiation induced dpa cross section. • Improvement about 5–50% for the electron irradiation induced dpa cross section. • More precise results (20–70%) for thin samples irradiated with electrons. - Abstract: Several authors had estimated the displacements per atom cross sections under different approximations and models, including most of the main gamma- and electron-material interaction processes. These previous works used numerical approximation formulas which are applicable for limited energy ranges. We proposed the Monte Carlo assisted Classical Method (MCCM), which relates the established theories about atom displacements to the electron and positron secondary fluence distributions calculated from the Monte Carlo simulation. In this study the MCCM procedure is adapted in order to estimate the displacements per atom cross sections for gamma and electron irradiation. The results obtained through this procedure are compared with previous theoretical calculations. An improvement in about 10–90% for the gamma irradiation induced dpa cross section is observed in our results on regard to the previous evaluations for the studied incident energies. On the other hand, the dpa cross section values produced by irradiation with electrons are improved by our calculations in about 5–50% when compared with the theoretical approximations. When thin samples are irradiated with electrons, more precise results are obtained through the MCCM (in about 20–70%) with respect to the previous studies.

  20. γ-irradiation effect on electronic properties in hydrogenated amorphous silicon

    International Nuclear Information System (INIS)

    Shirafuji, J.; Nagata, S.; Shirakawa, K.

    1986-01-01

    γ-irradiation effect on electron transport and photoelectric properties in glow-discharge hydrogenated amorphous silicon is investigated mainly by means of time-of-flight measurement. Although the electron transport changes from non-dispersive to dispersive when the total dose on γ-rays is increased, the electron mobility at room temperature is affected only slightly by γ-irradiation. The γ-irradiation introduces dominantly Si dangling bonds, allowing to study the recombination characteristic as a function of dangling bond density under controllable conditions. It is found that the electron recombination lifetime is inversely proportional to the dangling bond density. (author)

  1. Bending of metal-filled carbon nanotube under electron beam irradiation

    Directory of Open Access Journals (Sweden)

    Abha Misra

    2012-03-01

    Full Text Available Electron beam irradiation induced, bending of Iron filled, multiwalled carbon nanotubes is reported. Bending of both the carbon nanotube and the Iron contained within the core was achieved using two approaches with the aid of a high resolution electron microscope (HRTEM. In the first approach, bending of the nanotube structure results in response to the irradiation of a pristine kink defect site, while in the second approach, disordered sites induce bending by focusing the electron beam on the graphite walls. The HRTEM based in situ observations demonstrate the potential for using electron beam irradiation to investigate and manipulate the physical properties of confined nanoscale structures.

  2. Effect of electron beam irradiation on nutritional ingredient of Tegillarca granosa meat

    International Nuclear Information System (INIS)

    Li Chao; Yang Wenge; Xu Dalun; Ou Changrong; Shi Huidong

    2011-01-01

    The influences of 0, 1, 3, 5, 7 and 9 kGy electron beam irradiation on the contents of protein and amino acid and the composition of amino acids and fatty acids in Tegillarca granosa meat were investigated. The results showed that the electron beam had no significant effect on contents of moisture, ash and protein. Fat was sensitive to electron beam irradiation, which decreased with the increasing of irradiation dose. The composition of amino acids remained stable with different doses. The values of EAA/TAA and EAA/NEAA were kept in accordance with FAO/WHO protein model. Besides, electron beam irradiation made no effect on the limiting amino acid (the first and second limiting amino acids were Met + Cys and Val, respectively). The relative content of PUFA increased significantly 1 ∼ 7 kGy irradiation. Electron beam irradiation produced a notable impact on the essential fatty acid, induced the increase of linoleic acid, linolenic acid and arachidonic acid at the doses of 5 ∼ 9 kGy. After the irradiation of 9 kGy, the increments of relative contents of the three essential fatty acids reached 94.61%, 41.37% and 89.91%, respectively. Electron beam irradiation had positive effect on EPA with the doses of 3, 5 and 9 kGy. However, DHA was sensitive to electron beam irradiation, whose relative content decreased with the increasing of irradiation dose and undetected at the dose of 9 kGy. According to the research of decontamination effect, the recommended dose of electron beam irradiation on Tegillarca granosa ws fixed at 3 ∼ 5 kGy. (authors)

  3. Effect of electronic beam irradiation on development of Plodia interpunctella (Huebner)

    International Nuclear Information System (INIS)

    Fan Jialin; Chen Yuntang; Li Xuzhao; Guo Dongquan; Lu Xiaohua; Zhang Jianwei; Yang Bao'an; Liu Jiangyu; Tian Zhanjun; Zhang Xiaoyan

    2011-01-01

    The electronic beam irradiation effects on different developed stages of Plodia interpunctella Huebner were studied. The hatch rate, pupation rate, emergence rate and reproductive capacity of insect after irradiation were tested. The results showed that the order of sensitivity of the life stages of Plodia interpunctella Huebner to electron beam irradiation was: egg > larva > pupae > adult. The hatch rate, pupation rate, emergence rate and reproductive capacity significantly decreased with the increasing of irradiation dose (P<0.05). The egg, larvae, pupae couldn't grow to adults after irradiation at 100, 250 and 600 Gy, respectively. No new generation adult was found after the adults were irradiation at 600 Gy. It is concluded that 600 Gy irradiation could be used as a suitable dose to prevent the reproduction of Plodia interpunctella Huebner during the storage of tobacco. (authors)

  4. Effects of Electron Beam Irradiated Natural Casings on the Quality Characteristics of Emulsion Sausage

    International Nuclear Information System (INIS)

    Kim, Hyunwook; Kim, Hackyoun; Hwang, Koeun; Choi, Sunmi; Kim, Cheonjei; Choi, Jihun; Choi, Yunsang; Lee, Juwoon

    2011-01-01

    The effects of electron beam irradiated hog and sheep casings (1, 3, and 8 KGy) on the physicochemical properties and shelf stability of emulsion sausage were evaluated. There were no significantly differences in ph, instrumental color, and sensory evaluation among all the samples tested (p>0.05). The cooking yields for the irradiated treated samples were larger than the yields obtained for the non-irradiated samples for both the hog and sheep casing. However, the results on the purge loss after storage for 5 weeks were contradictory. The hardness of the sausage was lower when the irradiated natural casings were used. The irradiated natural casings accelerated lipid oxidation. The volatile basic nitrogen values were lower in samples treated with electron beam irradiation. The natural casings irradiated up to a dose of 3kGy not only had different total aerobic bacteria counts during the initial storage period but also displayed higher TAB counts at the final storage period

  5. Ultrastructure of Withania Somnifera (L.) Dunal pollen grains

    International Nuclear Information System (INIS)

    Alwadie, H.M.

    2002-01-01

    Light, scanning and transmission electron microscopy were used to study the morphology and ultrastructure of Withania Somnifera (L.) Dunall pollen grains. Light microscopic examination revealed that the pollen grains are tri- or tetrazonocoplate grains, approximately as long as broad, measuring 29-um. Scanning electron microscopic observation showed that surface sculpturing of the pollen is scarbate-granulate. Ultrathin sections as examined by transmission electron microscope showed that the pollen contained numerous starch grains, lipid droplets, endoplasmic reticulum and vesicles of dictyosomes. Two layers of the pollen wall were also distinguished, the outer wall (exine) divided into ektexine and endexine as well as the inner layer (intine). The nutritive values of Withania pollen are discussed. The importance of studying the ultrastructure of pollen grains as a new tool in palynology is also discussed. (author)

  6. Deuterium trapping at vacancy clusters in electron/neutron-irradiated tungsten studied by positron annihilation spectroscopy

    Science.gov (United States)

    Toyama, T.; Ami, K.; Inoue, K.; Nagai, Y.; Sato, K.; Xu, Q.; Hatano, Y.

    2018-02-01

    Deuterium trapping at irradiation-induced defects in tungsten, a candidate material for plasma facing components in fusion reactors, was revealed by positron annihilation spectroscopy. Pure tungsten was electron-irradiated (8.5 MeV at ∼373 K and to a dose of ∼1 × 10-3 dpa) or neutron-irradiated (at 573 K to a dose of ∼0.3 dpa), followed by post-irradiation annealing at 573 K for 100 h in deuterium gas of ∼0.1 MPa. In both cases of electron- or neutron-irradiation, vacancy clusters were found by positron lifetime measurements. In addition, positron annihilation with deuterium electrons was demonstrated by coincidence Doppler broadening measurements, directly indicating deuterium trapping at vacancy-type defects. This is expected to cause significant increase in deuterium retention in irradiated-tungsten.

  7. Changes in mechanical and chemical wood properties by electron beam irradiation

    International Nuclear Information System (INIS)

    Schnabel, Thomas; Huber, Hermann; Grünewald, Tilman A.; Petutschnigg, Alexander

    2015-01-01

    Highlights: • Changes in wood due to electron beam irradiations (EBI) were evaluated. • Wood components undergo different altering mechanisms due to the irradiation. • Chemical reactions in wood lead to better surface hardness of low irradiated wood. - Abstract: This study deals with the influence of various electron beam irradiation (EBI) dosages on the Brinell hardness of Norway spruce. The results of the hardness measurements and the FT-IR spectroscopic analysis show different effects of the EBI at dosages of 25, 50, 100 and 200 kGy. It was assumed that the lignin and carbohydrates undergo different altering mechanisms due to the EBI treatment. New cleavage products and condensation reactions of lignin and carbohydrates lead to better surface hardness of low irradiated wood samples. These results provide a useful basis for further investigations on the changes in wood chemistry and material properties due to electron beam irradiations

  8. Changes in mechanical and chemical wood properties by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Schnabel, Thomas, E-mail: thomas.schnabel@fh-salzburg.ac.at [Salzburg University of Applied Sciences, Department of Forest Products Technology and Wood Constructions, Marktstraße 136a, 5431 Kuchl (Austria); Huber, Hermann [Salzburg University of Applied Sciences, Department of Forest Products Technology and Wood Constructions, Marktstraße 136a, 5431 Kuchl (Austria); Grünewald, Tilman A. [BOKU University of Natural Resources and Life Sciences, Institute of Physics and Materials Science, Peter Jordan Straße 82, 1190 Vienna (Austria); Petutschnigg, Alexander [Salzburg University of Applied Sciences, Department of Forest Products Technology and Wood Constructions, Marktstraße 136a, 5431 Kuchl (Austria); BOKU University of Natural Resources and Life Sciences, Konrad Lorenzstraße 24, 3430 Tulln (Austria)

    2015-03-30

    Highlights: • Changes in wood due to electron beam irradiations (EBI) were evaluated. • Wood components undergo different altering mechanisms due to the irradiation. • Chemical reactions in wood lead to better surface hardness of low irradiated wood. - Abstract: This study deals with the influence of various electron beam irradiation (EBI) dosages on the Brinell hardness of Norway spruce. The results of the hardness measurements and the FT-IR spectroscopic analysis show different effects of the EBI at dosages of 25, 50, 100 and 200 kGy. It was assumed that the lignin and carbohydrates undergo different altering mechanisms due to the EBI treatment. New cleavage products and condensation reactions of lignin and carbohydrates lead to better surface hardness of low irradiated wood samples. These results provide a useful basis for further investigations on the changes in wood chemistry and material properties due to electron beam irradiations.

  9. Novel phenomena in clusters irradiated by short-wavelength free-electron lasers

    International Nuclear Information System (INIS)

    Fukuzawa, Hironobu; Ueda, Kiyoshi

    2017-01-01

    By electron spectroscopy, we investigated various phenomena that are caused by the irradiation of extreme ultraviolet (EUV) and X-ray free-electron laser (FEL) pulses on rare-gas clusters. The results for the Ne clusters, which were irradiated by EUVFEL pulses at a photon energy of 20.3 eV below the ionization threshold, illustrate that novel interatomic processes yield low-energy electrons. The results for the Xe clusters, irradiated by EUVFEL pulses at a photon energy of 24.3 eV above the threshold, illustrate that nanoplasma is formed as a result of trapping the photoelectrons and consequently emits low-energy thermal electrons. The results for the Ar clusters irradiated by 5 keV XFEL pulses illustrate that nanoplasma is formed by trapping low-energy Auger electrons and secondary electrons in the tens of fs range, and continuous thermal emission from the plasma occurs in the ps range. (author)

  10. Process for producing a coating composition. [electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, T; Harada, H; Kobayashi, S; Nakamoto, H; Sunano, K

    1968-07-19

    An easily hardenable acrylic coating composition is produced by irradiation with low energy electron beams to economize the industrial application of the composition. A polymer with molecular weights in the 5,000 to 500,000 range is composed of 1 to 40% by weight of a vinyl monomer containing a glycidyl radical, 30 to 99% of a methacrylic monomer and 0 to 69% of other copolymerizable vinyl monomers. This polymer dissolves in a monomer containing at least 30% of an acrylic monomer and 70% of other vinyl monomers. The reaction takes place between 0.1 to 1.0 mole of vinyl monomer containing a carboxyl radical and one mole of glycidyl radical in the solution. In an embodiment, 17.5% by weight of glycidyl methacrylate and 82.5% of alkyl acrylate are polymerized in suspension in the presence of a catalyst to form a bead like polymer with molecular weights in the 5,000 to 500,000 range. After 120 parts of the bead like polymer are dissolved in 180 parts of the acrylic monomer in the presence of a polymerization inhibitor by heating, 22 parts of ..cap alpha.., ..beta..- unsaturated monocarboxylic acid are added to the solution to react with the glycidyl radical, whereby a non-solvent type coating material containing the polymer having a vinyl radical side chain is produced. In the place of the catalyst, electron beams can be used at an energy level of 0.1 to 20 MeV. The dose rate may be in the range of 0.1 to 2.0 Mrad/sec.

  11. Experimental investigations of chromosomal aberrations following irradiation with fast electrons at various irradiation depths as influenced by sulfoguanidine

    International Nuclear Information System (INIS)

    Donnerstag, R.

    1975-01-01

    Root tips of Vicia faba were irradiated with fast electrons (14.2 MeV, 120 rad) in the phantom at a depth of 100% and 30% relative depth dose in culture medium and sulphoguanidine solution and were fixed after 3, 6, 9, 12 and 24 h. In contrast to the controls, a transitory mitotic depression was observed after irradiation. This effect was more marked for root tips irradiated in culture medium and much less pronounced in root tips irradiated in sulphoguanidine. When quantitatively assessing the anaphasal aberrations, the highest damage rate was found at 3 h p.r. This was attributed to the facts that these cells had been irradiated in the earliest G 2 phase. A second aberration peak was found 9 h after irradiation at 30% relative depth dose. These cells had been irradiated in the middle of the S phase. It is assumed that with increasing LET, euchromatic DNA regions are most readily damaged. When the two irradiation depths were compared, it was found that the aberration rate was significantly reduced after irradiation in sulphoguanidine solution at a depth of 30% relative dose. A qualitative assessment showed that fragments made up the highest and bridges the lowest fraction of aberrations, although there were variations in the single values depending on the irradiation conditions and culture media used. It was assumed that sulfoguanidine may have a positive influence on repair processes in damaged DNA, and that this influence depends on the energy spectrum of the irradiation. Furthermore, the possibility of a biochemical mechanism was discussed. (orig./MG) [de

  12. Electron irradiation experiments in support of fusion materials development

    International Nuclear Information System (INIS)

    Gelles, D.S.; Ohnuki, S.; Takahashi, H.; Matsui, H.; Kohno, Y.

    1991-11-01

    Microstructural evolution in response to 1 MeV irradiation has been investigated for three simple ferritic alloys, pure beryllium, pure vanadium, and two simple vanadium alloys over a range of temperatures and doses. Microstructural evolution in Fe-3, -9, and -18Cr ferritic alloys is found to consist of crenulated, faulted a loops and circular, unfaulted a/2 loops at low temperatures, but with only unfaulted loops at high temperatures. The complex dislocation evolution is attributed to sigma phase precipifaults arising from chromium segregation to point defect sinks. Beryllium is found to be resistant to electron damage; the only effect observed was enhanced dislocation mobility. Pure vanadium, V-5Fe, and V-1Ni microstructural response was complicated by precipitation on heating to 400 degrees C and above, but dislocation evolution was investigated in the range of room temperature to 300 degrees C and at 600 degrees C. The three materials behaved similarly, except that pure vanadium showed more rapid dislocation evolution. This difference does not explain the enhanced swelling observed in vanadium alloys

  13. Ignitor electrode system design for the pulses electron irradiators device

    International Nuclear Information System (INIS)

    Lely Susita RM; Ihwanul Aziz

    2016-01-01

    The designed ignitor electrode system is a system used to initiate the plasma discharge. It consists of two pieces which are placed on both side of the plasma vessel. Each of the ignitor electrode system consists of a cathode, an anode and insulator between the cathode and the anode. The best cathode material for ignitor electrode system is Mg due to its lowest ion erosion rate (γi =11.7 μg/C) and its low cohesive energy (1.51 eV). The specifications of ignitor electrode system designed for the pulse electron irradiators is as follow: Mg cathode materials in the form of rod having a diameter of 6.35 mm and length of 76.75 mm. Anode material are made of non magnetic of SS 304 cylinder shaped with an outer diameter of 88.53 mm, an inner diameter of 81.53 mm and a thickness of 3.50 mm. Insulating material between the cathode and the anode is made of teflon cylinder shaped, outer diameter of 9.50 mm, an inner diameter of 6.35 mm and a length of 30 mm. Based on the ignitor electrode system design, the next step is construction and function test of the ignitor electrode system. (author)

  14. Discrimination of damages depending on the types of lactic dehydrogenase isozymes in electron beam irradiation

    International Nuclear Information System (INIS)

    Ohta, Akishige; Matsubayashi, Takashi; Liu Xiaolan; Takizawa, Haruki.

    1995-01-01

    Lactate dehydrogenase (EC 1.1.1.27,LDH) was a tetrameric molecule. The five different combinations of two different polypeptide chains can be readily identified by electrophoresis and ion-exchange chromatography. Injury patterns of LDH activity following electron-beam irradiation was investigated by assaying activities of three isozymes (pig heart LDH;M 4 , rabbit muscle LDH;H 4 , chicken heart LDH;M 3 H 1 ). Following results were obtained in the electron beam irradiation to three kinds of LDH isozymes: 1) Each isozyme has respective different reactivities to the electron beam irradiation. 2) Among the isozymes, M 4 enzyme was increased its enzymatic activity by the irradiations of low-level doses. 3) For the H 4 enzymes, an increasing phenomenon of -SH group was found in the low-level doses of electron beam irradiation. (author)

  15. A Study on the Thermal Neutron Filter for the Irradiation of Electronic Materials at HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Seong Woo; Kim, Sung Ryul; Park, Seung Jae; Shin, Yoon Taeg; Cho, Man Soon; Cho, Kee Nam [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The representative example is a technique of making the semiconductor with the transmutation using the pure Si. This NTD (Neutron Transmutation Doping) Si is used as a high-quality semiconductor because it has a uniform resistance. Likewise, the electronic materials are being investigated to improve the performance of material using the neutron irradiation method. The mechanism for reaction between the electronic materials and the neutrons depends on the energy of the neutron. Capturing reaction by thermal neutrons causes the transmutation and a lot of defects are made by fast neutrons. The study for the effect by such neutron energy is necessary to understand the performance improvement of the irradiated electronic materials. The thermal neutron filter was investigated to be used for the irradiation of electronic materials at HANARO. IP irradiation hole was selected and the irradiation device was designed. The analysis was conducted considering four candidate materials.

  16. Change of the functional properties in polysaccharides irradiated by electron beam

    International Nuclear Information System (INIS)

    Sakaue, Kazushi; Murata, Yoshiyuki; Tada, Mikiro; Hayashi, Toru; Todoriki, Setsuko; Asai, Kazuo

    1998-01-01

    Polysaccharides widely used in the food industry were studied in terms of sterilization of bacteria by irradiation. 12 items of polysaccharides irradiated by electron beam ware investigated for bacteria count and the functional property of pH, gel strength, bloom and viscosity. This study aims to determine the sterilization effect by absorption dose and the applicability of the electron beam irradiation toward polysaccharides. Results shows that 1) Over 5kGy absorption dose are enough to be able to sterilize bacteria in the polysaccharide themselves. 2) We reconfirm that Arabic gum will be applicable for the electron beam irradiation, which has been used in some foreign countries. 3) Electron beam irradiation will be useful for Gellan gum b (acetyl type), as gelling agents in the food application. (author)

  17. Electron irradiated liquid encapsulated Czochralski grown undoped gallium antimonide studied by positron lifetime spectroscopy and photoluminescence

    International Nuclear Information System (INIS)

    Ma, S K; Lui, M K; Ling, C C; Fung, S; Beling, C D; Li, K F; Cheah, K W; Gong, M; Hang, H S; Weng, H M

    2004-01-01

    Electron irradiated undoped liquid encapsulated Czochralski (LEC) grown GaSb samples were studied by positron lifetime spectroscopy (PLS) and photoluminescence (PL). In addition to the 315 ps component reported in the previous studies, another defect with a lifetime of 280 ps was also identified in the present electron irradiated samples. The bulk lifetime of the GaSb material was found to be 258 ps. The V Ga,280ps and the V Ga,315ps defects were associated with two independent Ga vacancy related defects having different microstructures. The well known 777 meV PL signal (usually band A) was also observed in the electron irradiated undoped GaSb samples. The band A intensity decreases with increasing electron irradiation dosage and it disappears after the 300 deg. C annealing regardless of the irradiation dosage. The origin of the band A signal is also discussed

  18. Comparison of electron and ion irradiation effects on order-disorder transition in Ni4Mo

    International Nuclear Information System (INIS)

    Banerjee, S.; Sundararaman, M.

    1996-01-01

    The effects of radiation damage in metals and alloys caused by electron and heavy ion beams are quite distinct from the consideration of cascade formation. Microstructural changes occurring with progressive dose of irradiation under cascade forming heavy ion irradiation and under electron irradiation have been systematically studied in Ni 4 Mo in the temperature range of 300 to 1050 K. The ordering transformation in this alloy can be used in understanding the fundamental processes of radiation damage. Conversely, radiation experiments provide an insight into the ordering mechanisms. The ordering in this alloy is governed by a competition between a second order and a first order ordering process. Steady state structures developed at different temperatures have been characterised by electron diffraction and imaging. The steady state diagrams are constructed and compared for both electron and ion irradiation. The essential difference between the nature of cascade forming and non-cascade forming irradiation on the order-disorder transformation has been discussed. (orig.)

  19. Calibration of dosimeters at 80-120 keV electron irradiation

    DEFF Research Database (Denmark)

    Miller, A.; Helt-Hansen, J.

    to calibrate thin-film dosimeters (Risø B3 and alanine films) by irradiation at the 80–120 keV electron accelerators. This calibration was compared to a 10MeV calibration, and we show that the radiation response of the dosimeter materials (the radiation chemical yield) is constant at these irradiation energies....... However, dose gradients within the dosimeters, when it is irradiated at low electron energies,mean that calibration function here will depend on both irradiation energy and the required effective point of measurement of the dosimeter. These are general effects that apply to any dosimeter that has a non...

  20. Effects of proton irradiation on electronic structure of NdFeB permanent magnets

    Energy Technology Data Exchange (ETDEWEB)

    Yang, L. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Zhen, L. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)], E-mail: lzhen@hit.edu.cn; Xu, C.Y.; Sun, X.Y.; Shao, W.Z. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2009-09-15

    Effects of proton irradiation on electronic structure and atomic local structure of N35EH-type NdFeB permanent magnet were investigated by soft X-ray absorption spectrometry and Moessbauer spectrometry. The local coordination environment of Fe atoms changes after proton irradiation, and the average hyperfine field H{sub in} of the magnets decreases from 288.4 to 286.9 kOe. The effects of irradiation on Fe atoms local environment at different lattice sites are different. The near edge structure of Fe L{sub 3} edge is changed, indicating the density of unoccupied state of Fe 3d electrons increases after proton irradiation.

  1. Effect of electron-beam irradiation on the antioxidant activity of extracts from Citrus unshiu pomaces

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong-Wan [Department of Food Science and Biotechnology, Kyungnam University, Masan 631-701 (Korea, Republic of); Lee, Byung Cheol [Laboratory for Quantum Optics, Korea Atomic Energy Research Institute, Daejeon 305-600 (Korea, Republic of); Lee, Jong-Hwa [School of Bioresource Sciences, Andong National University, Andong 760-749 (Korea, Republic of); Nam, Ki-Chang [Chemistry and Biotechnology Examinations Bureau, Korean Intellectual Property Office, Daejeon 302-701 (Korea, Republic of); Lee, Seung-Cheol [Department of Food Science and Biotechnology, Kyungnam University, Masan 631-701 (Korea, Republic of)], E-mail: sclee@kyungnam.ac.kr

    2008-01-15

    After electron-beam irradiation of citrus pomaces (CP), the total phenolic content (TPC), radical scavenging activity (RSA), and reducing power (RP) were evaluated. When CP were irradiated at 37.9 kGy; the TPC, RSA and RP of water extract of CP increased from 6543.2 to 7405.4 {mu}M, 37.6% to 52.9%, and 0.64 to 0.90, respectively, compared with the non-irradiated control. The results indicate that the electron-beam irradiation can be an efficient process for increasing the antioxidant activity of CP.

  2. Transmission electron-microscopic studies of structural changes in polycrystalline graphite after high temperature irradiation

    International Nuclear Information System (INIS)

    Platonov, P.A.; Gurovich, B.A.; Shtrombakh, Ya.I.; Karpukhin, V.I.

    1985-01-01

    Transmission electron-microscopic investigation of polycrystalline graphite before and after irradiation is carried out. The direct use of graphite samples after ion thinning, as an inquiry subject is the basic peculiarity of the work. Main structural components of MPG-6 graphite before and after irradiation are revealed, the structural mechanism of the reactor graphite destruction under irradiation is demonstrated. The mean values of L αm and L cm crystallite dimensions are determined. Radiation defects, occuring in some crystallites after irradiation are revealed by the dark-field electron microscopy method

  3. The thermal and mechanical properties of electron beam-irradiated polylactide

    International Nuclear Information System (INIS)

    Kuk, In Seol; Jung, Chan Hee; Hwang, In Tae; Choi, Jae Hak; Nho, Young Chang

    2010-01-01

    The effect of electron beam irradiation on the thermal and mechanical properties of polylactide (PLA) was investigated in this research. PLA films were irradiated by electron beams at different absorption doses ranging from 20 to 200 kGy. The thermal and mechanical properties of the irradiated PLA films were investigated by means of differential scanning calorimeter, thermogravimetric analyzer, universal testing machine, dynamic mechanical analyzer, and thermal mechanical analyzer. The results revealed that the chain scission of the PLA predominated over the crosslinking during the irradiation, which considerably deteriorated the thermal and mechanical properties of the PLA

  4. Preliminary examination of induced radio activity in pepper by 10 MeV electron irradiation

    International Nuclear Information System (INIS)

    Furuta, Masakazu; Katayama, Tadashi; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Toratani, Hirokazu; Takeda, Atsuhiko

    1989-01-01

    β-ray measurement was performed on 10 MeV electron-irradiated black pepper and white pepper in order to reconfirm the wholesomeness of irradiated food and present unambiguous data to general consumers concerning about the induced radioactivity in the irradiated foods. From elemental composition of the samples and investigation of photonuclear reactions, several β-emmitters were listed up. But no radioactivity other than from natural sources was detected in the irradiated sample by β-ray counting with 2 π gass flow counter, suggesting that the induced β-emmitters in the irradiated sample was below the detection limit of its induced radioactivity. (author)

  5. Lateral propagation of MeV electrons generated by femtosecond laser irradiation

    International Nuclear Information System (INIS)

    Seely, J. F.; Szabo, C. I.; Audebert, P.; Brambrink, E.; Tabakhoff, E.; Hudson, L. T.

    2010-01-01

    The propagation of MeV electrons generated by intense (≅10 20 W/cm 2 ) femtosecond laser irradiation, in the lateral direction perpendicular to the incident laser beam, was studied using targets consisting of irradiated metal wires and neighboring spectator wires embedded in electrically conductive (aluminum) or resistive (Teflon) substrates. The K shell spectra in the energy range 40-60 keV from wires of Gd, Dy, Hf, and W were recorded by a transmission crystal spectrometer. The spectra were produced by 1s electron ionization in the irradiated wire and by energetic electron propagation through the substrate material to the spectator wire of a different metal. The electron range and energy were determined from the relative K shell emissions from the irradiated and spectator wires separated by varying substrate lateral distances of up to 1 mm. It was found that electron propagation through Teflon was inhibited, compared to aluminum, implying a relatively weak return current and incomplete space-charge neutralization. The energetic electron propagation in the direction parallel to the electric field of the laser beam was larger than perpendicular to the electric field. Energetic electron production was lower when directly irradiating aluminum or Teflon compared to irradiating the heavy metal wires. These experiments are important for the determination of the energetic electron production mechanism and for understanding lateral electron propagation that can be detrimental to fast-ignition fusion and hard x-ray backlighter radiography.

  6. Degradation mechanism of polyurethane foam induced by electron beam irradiation

    International Nuclear Information System (INIS)

    Huang Wei; Fu Yibei; Bian Zhishang; He Meiying

    2002-01-01

    The degradation mechanism of irradiated polyurethane foam has been studied in detail. The changes of chemical structure and micro-phase separation have been determined by DTG. The gas products from irradiated samples are analyzed quantitatively and qualitatively by GC. The degradation mechanism of irradiated polyurethane foam has been deduced according to the experimental results. It provides some basis of the application on the polyurethane in the radiation field

  7. Electron spin resonance studies of some irradiated pharmaceuticals

    International Nuclear Information System (INIS)

    Gibella, M.; Crucq, A-S.; Tilquin, B.; Stocker, P.; Lesgards, G.; Raffi, J.

    2000-01-01

    Five antibiotics belonging to the cephalosporins and penicillins groups have been irradiated: anhydrous ampicilline acid, amoxicilline acid trihydrate, cefuroxime sodium salt, cloxacilline sodium salt monohydrate and ceftazidime pentahydrate. ESR studies have been carried out, showing the influence of irradiation and storage parameters on the nature and concentration of the free radicals trapped. These results may be used to detect an irradiation treatment on such pharmaceuticals. (author)

  8. Enhancement of biodegradability of real textile and dyeing wastewater by electron beam irradiation

    International Nuclear Information System (INIS)

    He, Shijun; Sun, Weihua; Wang, Jianlong; Chen, Lvjun; Zhang, Youxue; Yu, Jiang

    2016-01-01

    A textile and dyeing wastewater treatment plant is going to be upgraded due to the stringent discharge standards in Jiangsu province, China, and electron beam irradiation is considering to be used. In order to determine the suitable location of the electron accelerator in the process of wastewater treatment plant, the effects of electron beam (EB) irradiation on the biodegradability of various real wastewater samples collecting from the different stages of the wastewater treatment plant, the values of chemical oxygen demand (COD), biochemical oxygen demand (BOD 5 ), and the ratio of BOD 5 and COD (BOD 5 /COD), were compared before and after EB irradiation. During EB irradiation process, color indices and absorbance at 254 nm wavelength (UV 254 ) of wastewater were also determined. The results showed that EB irradiation pre-treatment cannot improve the biodegradability of raw textile and dyeing wastewater, which contains a large amount of biodegradable organic matters. In contrast, as to the final effluent of biological treatment process, EB irradiation can enhance the biodegradability to 224%. Therefore, the promising way is to apply EB irradiation as a post-treatment of the conventional biological process. - Highlights: • Irradiation pre-treatment did not improve the raw textile wastewater biodegradability. • Irradiation can highly enhance the biodegradability of biological treated effluent. • EB irradiation can be used as a post-treatment after biological process.

  9. Bias dependent charge trapping in MOSFETs during 1 and 6 MeV electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, N.S. [Department of Chemical Engineering, Mie University, 5148507 (Japan); Kulkarni, V.R.; Mathakari, N.L.; Bhoraskar, V.N. [Department of Physics, Univeristy of Pune, Pune 411007 (India); Dhole, S.D. [Department of Physics, Univeristy of Pune, Pune 411007 (India)], E-mail: sanjay@physics.unipune.ernet.in

    2008-06-15

    To study irradiation-induced charge trapping in SiO{sub 2} and around the SiO{sub 2}-Si interface, depletion n-MOSFETs (metal-oxide-semiconductor field effect transistor) were used. The devices were gate biased during 1 and 6 MeV pulsed electron irradiation. The I{sub D}-V{sub DS} (drain current versus drain voltage) and I{sub D}-V{sub GS} (drain current versus gate voltage) characteristics were measured before and after irradiation. The shift in threshold voltage {delta}V{sub T} (difference in threshold voltage V{sub T} before and after irradiation) exhibited trends depending on the applied gate bias during 1 MeV electron irradiation. This behavior can be associated to the contribution of irradiation-induced negative charge {delta}N{sub IT} buildup around the SiO{sub 2}-Si interface to {delta}V{sub T}, which is sensitive to the electron tunneling from the substrates. However, only weak gate bias dependence was observed in 6 MeV electron irradiated devices. Independent of the energy loss and applied bias, the positive oxide trapped charge {delta}N{sub OT} is marginal and can be associated to thin and good quality of SiO{sub 2}. These results are explained using screening of free and acceptor states by the applied bias during irradiation, thereby reducing the total irradiation-induced charges.

  10. Pollen of Southeast Asian Alchornea (Euphorbiaceae), with an overview of the pollen fossil record

    NARCIS (Netherlands)

    Bulalacao, L.J.; Ham, van der R.W.J.M.

    2003-01-01

    In order to evaluate pollen morphological descriptions of Alchornea in the literature, which are almost completely based on African and American species, the pollen of eight Southeast Asian species of Alchornea was investigated, using light and scanning electron microscopy. Very little variation

  11. 78 FR 27303 - Irradiation in the Production, Processing, and Handling of Animal Feed and Pet Food; Electron...

    Science.gov (United States)

    2013-05-10

    ...-0178] Irradiation in the Production, Processing, and Handling of Animal Feed and Pet Food; Electron... electron beam and x-ray sources for irradiation of poultry feed and poultry feed ingredients. This action... CFR part 579) to provide for the safe use of electron beam and x-ray sources for irradiation of...

  12. Electron microscopic study of the spilt irradiation effects on the rat parotid ductal cells

    International Nuclear Information System (INIS)

    Kim, Sung Soo; Lee, Sang Rae

    1988-01-01

    This study was designed to investigate the effects of split irradiation on the salivary ductal cells, especially on the intercalated cells of the rat parotid glands. For this study, 24 Sprague-Dawley strain rats were irradiated on the head and neck region with two equal split doses of 9 Gy for a 4 hours interval by Co-60 teletherapy unit, Picker's mode l 4M 60. The conditions of irradiation were that field size, dose rate, SSD and depth were 12 X 5 cm, 222 cGy/min, 50 cm and 1 cm, respectively. The experimental animals were sacrificed 1, 2, 3, 6, 12, hours and 1, 3, 7, days after the irradiation and the changes of the irradiated intercalated cells of the parotid glands were examined under light and electron microscope. The results were as follows: 1. By the split irradiation, the degenerative changes of intercalated cells of the parotid glands appeared at 3 hours after irradiation and the most severe cellular degeneration observed at 6 hours after irradiation. The repair processes began from 12 hours after irradiation and have matured progressively. 2. Under electron microscope, loss of nuclear membrane, microvilli and secretory granules, derangement of chromosomes, degeneration of cytoplasm, atrophy or reduction of intracytoplasmic organelles were observed in the intercalated ductal cells after split irradiation. 3. Under light microscope, derangement of ductal cells, widening of cytoplasms and nuclei, hyperchromatism and proliferation of ductal cells were observed in intercalated ducts after split irradiation.

  13. Deactivation of group III acceptors in silicon during keV electron irradiation

    International Nuclear Information System (INIS)

    Sah, C.; Sun, J.Y.; Tzou, J.J.; Pan, S.C.

    1983-01-01

    Experimental results on p-Si metal-oxide-semiconductor capacitors (MOSC's) are presented which demonstrate the electrical deactivation of the acceptor dopant impurity during 8-keV electron irradiation not only in boron but also aluminum and indium-doped silicon. The deactivation rates of the acceptors during the 8-keV electron irradiation are nearly independent of the acceptor impurity type. The final density of the remaining active acceptor approaches nonzero values N/sub infinity/, with N/sub infinity/(B) Al--H>In-H. These deactivation results are consistent with our hydrogen bond model. The thermal annealing or regeneration rate of the deactivated acceptors in the MOSC's irradiated by 8-keV electron is much smaller than that in the MOSC's that have undergone avalanche electron injection, indicating that the keV electron irradiation gives rise to stronger hydrogen-acceptor bond

  14. Effect of electron beam irradiation on the quality of mackerel (Pneumatophorus japonicus) Meat

    International Nuclear Information System (INIS)

    Wu Dongxiao; Yang Wenge; Xu Dalun; Zhou Xingyu; Ou Changrong; Shi Huidong

    2012-01-01

    The effect of 3, 5, 7 kGy electron beam irradiation on the volatile basic nitrogen (VBN) and peroxide value (POV), the contents of histamine and unsaturated fatty acid (UFA) in Pneumatophorus japonicus meat with vacuum or ordinary package were measured during refrigeration. The results showed that electron beam treatment could effectively control the contents of histamine and VBN, postpone the oxidation of unsaturated fatty acid in P. japonicus meat. The shelf life of P. japonicus meat could be extended with electron beam irradiation. Before cold storage, it is appropriate that the P. japonicus meat were ordinary packaged and irradiated at the dose of 5 kGy. (authors)

  15. Further study of the glassy low-temperature properties of irradiated crystalline quartz: neutron and electron irradiation

    International Nuclear Information System (INIS)

    Laermans, C.; Daudin, B.

    1979-01-01

    Recently it has been shown that a quartz crystal after light fast neutron irradiation shows low temperature hypersonic properties which are similar to those found in glasses although the sample was still crystalline. Additional measurements have been carried out in the neutron-irradiated sample and a sample irradiated with high energy electrons has also been investigated. (Fast neutron dose 6 x 10 18 n/cm 2 , 2 MeV electron dose 3 x 10 19 e/cm 2 ). A magnetic field up to 1.5 T was found to have no influence in the hypersonic saturation behaviour of the neutron-irradiated sample (9 GHz, 1.65 K) and thermal conductivity measurements are consistent with a number of two level systems (2 LS) an order of magnitude lower than in vitreous silica as found before. Low temperature hypersonic measurements as a function of acoustic intensity and temperature as well as thermal conductivity measurements give no evidence for the presence of 2 LS in the electron irradiated sample. Considering the damage created in both samples this indicates that 2 LS are probably not related to point defects

  16. The prophylactic effect of neck irradiation combined with intra-oral electron beam irradiation for early tongue cancer

    International Nuclear Information System (INIS)

    Kawamori, Jiro; Kamata, Rikisaburo; Sanuki, Eiichi

    1993-01-01

    Between 1967 and 1988, 102 patients with Stage T1-2N0 squamous cell carcinoma of the tongue were treated with uneven fractional irradiation therapy (intra-oral electron beam irradiation with and without prophylactic ipsilateral upper neck irradiation at the Dept. of Radiology, Nihon University School of Medicine. Of 102 primary lesions, 89 cases were controlled with this therapy. In this study, these 89 cases were investigated in order to analyze the prophylactic effect of upper neck irradiation. Of the 89 patients, 42 received only intra-oral electron beam irradiation, while the remaining 47 received a combination of intra-oral electron beam irradiation and prophylactic irradiation to the ipsilateral upper neck. Twenty three of the 89 (25.8%) developed metastasis to the neck after the radiotherapy. A breakdown of these 23 cases reveals that 3/21 (14.3%) received 40-50 Gy to the neck, 9/26 (34.6%) received 20-40 Gy to the neck, and 11/42 (26.2%) received no irradiation to the neck (p<0.05 between first and second groups, and between first and third groups). The neck metastasis was classified into one of three categories based on the region in which it first appeared (ipsilateral upper neck, ipsilateral lower neck or contralateral neck). The first metastasis was seen in the ipsilateral upper neck, in the ipsilateral lower neck and in the contralateral neck in 17, 4 and 2 patients, respectively. In 1/19 who had received 40-50 Gy, in 5/21 who had received 20-40 Gy and in 11/42 who had not received neck irradiation the first metastasis appeared in the ipsilateral upper neck. The five year survival rate was 94%, 75% and 85% in the patients receiving 40-50 Gy, 20-40 Gy and no neck irradiation, respectively. These results suggest that prophylactic irradiation of 40-50 Gy to the ipsilateral upper neck might decrease the incidence of neck metastasis and slightly prolong survival time. (author)

  17. Modification of PLGA Nanofibrous Mats by Electron Beam Irradiation for Soft Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Jae Baek Lee

    2015-01-01

    Full Text Available Biodegradable poly(lactide-co-glycolide (PLGA has found widespread use in modern medical practice. However, the degradation rate of PLGA should be adjusted for specific biomedical applications such as tissue engineering, drug delivery, and surgical implantation. This study focused on the effect of electron beam radiation on nanofibrous PLGA mats in terms of physical properties and degradation behavior with cell proliferation. PLGA nanofiber mats were prepared by electrospinning, and electron beam was irradiated at doses of 50, 100, 150, 200, 250, and 300 kGy. PLGA mats showed dimensional integrity after electron beam irradiation without change of fiber diameter. The degradation behavior of a control PLGA nanofiber (0 kGy and electron beam-irradiated PLGA nanofibers was analyzed by measuring the molecular weight, weight loss, change of chemical structure, and fibrous morphology. The molecular weight of the PLGA nanofibers decreased with increasing electron beam radiation dose. The mechanical properties of the PLGA nanofibrous mats were decreased with increasing electron beam irradiation dose. Cell proliferation behavior on all electron beam irradiated PLGA mats was similar to the control PLGA mats. Electron beam irradiation of PLGA nanofibrous mats is a potentially useful approach for modulating the biodegradation rate of tissue-specific nonwoven nanofibrous scaffolds, specifically for soft tissue engineering applications.

  18. The role of electron irradiation history in liquid cell transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Trevor H.; Mehta, Hardeep S.; Park, Chiwoo; Kelly, Ryan T.; Shokuhfar, Tolou; Evans, James E.

    2018-04-20

    In situ liquid cell transmission electron microscopy (LC-TEM) allows dynamic nanoscale characterization of systems in a hydrated state. Although powerful, this technique remains impaired by issues of repeatability that limit experimental fidelity and hinder the identification and control of some variables underlying observed dynamics. We detail new LC- TEM devices that improve experimental reproducibility by expanding available imaging area and providing a platform for investigating electron flux history on the sample. Irradiation history is an important factor influencing LC-TEM results that has, to this point, been largely qualitatively and not quantitatively described. We use these devices to highlight the role of cumulative electron flux history on samples from both nanoparticle growth and biological imaging experiments and demonstrate capture of time zero, low-dose images on beam-sensitive samples. In particular, the ability to capture pristine images of biological samples, where the acquired image is the first time that the cell experiences significant electron flux, allowed us to determine that nanoparticle movement compared to the cell membrane was a function of cell damage and therefore an artifact rather than visualizing cell dynamics in action. These results highlight just a subset of the new science that is accessible with LC-TEM through the new multiwindow devices with patterned focusing aides.

  19. Contribution of Brazil nut shell fiber and electron-beam irradiation in thermomechanical properties of HDPE

    International Nuclear Information System (INIS)

    Polato, Pamella; Lorusso, Leandro Alex; Souza, Clecia de Moura; Moura, Esperidiana Augusta Barretos de; Chinellato, Anne; Rosa, Ricardo de

    2010-01-01

    In the present work, the influence of electron-beam irradiation on thermo-mechanical properties of HDPE and HDPE/Brazil nut shell fiber composite was investigated. The materials were irradiated at radiation dose 50 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated samples were submitted to thermo-mechanical tests and the correlation between their properties was discussed. The results showed that the incorporation of Brazil nut shell fiber represented a significant gain (p < 0,05) in tensile strength at break, flexural strength, flexural module, Vicat softening temperature and heat distortion temperature (HDT) properties of the HDPE. In addition, the irradiated HDPE/Brazil nut shell fiber composite presented a significant increase (p < 0.05) in this properties compared with irradiated HDPE. (author)

  20. Extra spots in the electron diffraction patterns of neutron irradiated zirconium and its alloys

    International Nuclear Information System (INIS)

    Madden, P.K.

    1977-01-01

    Specimens of neutron irradiated zirconium and its alloys were examined in the transmission electron microscope. Groups of extra spots, often exhibiting four-fold symmetry, were observed in thin foil electron diffraction patterns of these specimens. The 'extra-spot' structure, like the expected black-dot/small scale dislocation loop neutron irradiated damage, is approximately 100 A in size. Its nature is uncertain. It may be related to irradiation damage or to some artefact introduced during specimen preparation. If it is the latter, then published irradiation damage defect size distributions and determined irradiation growth strains of other investigators, may require modification. The present inconclusive results indicate that extra-spot structure is likely to consist of oxide particles, but may correspond to hydride precipitation or decoration effects, or even, to electron beam effects. (author)

  1. Preliminary research concerning the using of electron accelerator for irradiation of fresh seasonal fruits

    International Nuclear Information System (INIS)

    Ferdes, O.; Stroia, A.L.; Potcoava, A.; Cojocaru, M.; Minea, R.; Oproiu, C.

    1994-01-01

    There were performed preliminary electron-beam irradiation of strawberries, cherries, and sour cherries. The irradiations were carried out with the IPTRD's electron acceleration at 6 MeV, at different dose-rates, particularly at 1-3 kGy for strawberries, and 0.5-2.0 kGy for cherries. The dosimetry was performed using a PTW medical dosemeter. After irradiation the samples were controlled and preserved at 8-10 o C, 75-85% r.h. The fruits were then analysed for organoleptic and nutritional preservation characteristics , sugars, acidity, C-vitamin, etc. They were also examined in order to find criteria for identification of irradiated fruits. The results show a good shelf-life extension for 5-15 days and the suggest the capability of using the electron-beam irradiation technologies in agro-food industry. (Author)

  2. An Economic Analysis for using Gamma and Electron Irradiation Technology in Preservation of Wheat in Egypt

    International Nuclear Information System (INIS)

    El-Gameel, E.A.

    2011-01-01

    The present study discusses the economic analysis of wheat irradiation in Egypt. This study was divided into four sections; the first section included the arrangement of the equation of simple regression foretelling the future of wheat import and national production. The second section include the financial analysis of electron beam accelerator facility, the third section discusses the financial analysis of gamma irradiation facility and the fourth section discusses the national return of wheat irradiation

  3. Changes of surface electron states of InP under soft X-rays irradiation

    International Nuclear Information System (INIS)

    Yang Zhian; Yang Zushen; Jin Tao; Qui Rexi; Cui Mingqi; Liu Fengqin

    1999-01-01

    Changes of surface electronic states of InP under 1 keV X-ray irradiation is studied by X-ray photoelectron spectroscopy (XPS) and ultraviolet ray energy spectroscopy (UPS). The results show that the soft X-ray irradiation has little effect on In atoms but much on P atoms. The authors analysed the mechanism of irradiation and explained the major effect

  4. Sterilizing effect of irradiation for Zuogui power with electron beam and γ-rays

    International Nuclear Information System (INIS)

    Yue Ling; Kong Qiulian; Qi Wenyuan; Bao Yingzi; Chen Zhijun; Yuan Zhongyi

    2011-01-01

    The sterilizing effect of irradiation for Zuogui powder with accelerator (electron beam) and a cobalt unit (γ-rays) was studied. The results indicated that the D 10 values of E-beam irradiation and γ-rays irradiation were 2.602 kGy and 2.597 kGy for aerobic bacterial count, while those were 3.112 kGy and 3.208 kGy for mould and yeasts. (authors)

  5. Electron paramagnetic resonance study on n-type electron-irradiated 3C-SiC

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, P; Rabia, K; Son, N T; Janzen, E [Department of Physics, Chemistry and Biology, Linkoeping University, SE-581 83 Linkoeping (Sweden); Ohshima, T; Morishita, N; Itoh, H [Japan Atomic Energy Research Institute, Takasaki 370-1292 (Japan); Isoya, J [University of Tsukuba, Tsukuba 305-8550 (Japan)], E-mail: paca@ifm.liu.se

    2008-03-15

    Electron Paramagnetic Resonance (EPR) was used to study defects in n-type 3C-SiC films irradiated by 3-MeV electrons at room temperature with a dose of 2x10{sup 18} cm{sup -2}. After electron irradiation, two new EPR spectra with an effective spin S = 1, labeled L5 and L6, were observed. The L5 center has C{sub 3v} symmetry with g = 2.004 and a fine-structure parameter D = 436.5x10{sup -4} cm{sup -1}. The L5 spectrum was only detected under light illumination and it could not be detected after annealing at {approx}550{sup 0}C. The principal z-axis of the D tensor is parallel to the <111>-directions, indicating the location of spins along the Si-C bonds. Judging from the symmetry and the fact that the signal was detected under illumination in n-type material, the L5 center may be related to the divacancy in the neutral charge state. The L6 center has a C{sub 2v}-symmetry with an isotropic g-value of g = 2.003 and the fine structure parameters D = 547.7x10{sup -4} cm{sup -1} and E = 56.2x10{sup -4} cm{sup -1}. The L6 center disappeared after annealing at a rather low temperature ({approx}200 deg. C), which is substantially lower than the known annealing temperatures for vacancy-related defects in 3C-SiC. This highly mobile defect may be related to carbon interstitials.

  6. The effects of electron beam irradiation on sterilization and preservation of chilled pork

    International Nuclear Information System (INIS)

    Bai Yanhong; Mao Duobin; Zhao Dianbo; Zhang Xiaoyan; Li Quanshun; Yang Gongming

    2009-01-01

    S The effects of electron beam irradiation on the sterilization and preservation of chilled pork were studied. The aim of this investigation was to provide academic and technical basis for application of electron beam irradiation on meat industry. The response surface analysis was used with electron beam energy(X 1 ) and dose(X 2 ) as factors and colony form unit(Y) as responses. The results have been shown that the model of sterilization of chilled pork by electron beam irradiation can be expressed Y=3.78-0.24X 1 -0.13X 2 -0.16X 1 X 2 -0.18X 1 2 +0.15X 1 2 (R 2 =0.9755). It has been found there is a interaction between electron beam energy and absorbed doses, and the significance sequence of factors is absorbed dose>interaction> electron beam energy. When absorbed doses are in range from 3.23 kGy to 4.0 kGy and electron beam energy is in range from 2.3 MeV to 3.8 MeV, the colony form unit would drop 2 logarithm units. The shelf life of samples treated with electron beam irradiation is longer by about 12 d than that of control samples when the samples are stored at 4 degree C. When the samples are stored at 7∼10 degree C, shelf life of samples treated with electron beam irradiation is longer by about 9 d than that of control samples. The results showed that electron beam irradiation has the effects of sterilization and preservation on chilled pork. This study has been confirmed that the application of electron beam irradiation is very useful for meat industry. (authors)

  7. Immunogold electron microscopic localization of timothy grass (Phleum pratense) pollen major allergens Phl p I and Phl p V after anhydrous fixation in acrolein vapor

    NARCIS (Netherlands)

    Grote, M.; Dolecek, C.; van Ree, R.; Valenta, R.

    1994-01-01

    We used the vapor phase of acrolein as an anhydrous fixative for timothy grass pollen in an immunogold double-labeling localization study of two different major allergens, Phl p I and Phl p V. More than 48 hr of fixation were needed for the subcellular pollen structures to be satisfactorily

  8. OBSERVATION OF MAGNETIC DOMAINS IN IRRADIATED TRANSITION METALS BY HIGH VOLTAGE ELECTRON MICROSCOPY

    OpenAIRE

    Ono , F.; Jakubovics , J.; Maeta , H.

    1988-01-01

    The effect of irradiation on the movement of domain walls was studied in ferromagnetic transition metals by using a high voltage electron microscope. In iron, a domain wall became easily movable at a 300 kV irradiation. The mobility was less affected in cobalt, while in nickel the effect was the greatest.

  9. Amorphization of Zr3Al by hydrogenation and subsequent electron irradiation

    International Nuclear Information System (INIS)

    Meng, W.J.; Koike, J.; Okamoto, P.R.; Rehn, L.E.

    1988-12-01

    1-MeV electron irradiation of hydrogenated Zr 3 Al (Zr 3 AlH/sub 0.96/) at 10K is studied. A more than 20 fold reduction in the critical dose required for complete amorphization is observed for the hydrogenated specimen as compared to the un-hydrogenated Zr 3 Al under identical irradiation conditions. 11 refs., 4 figs

  10. A point of view about identification of irradiated foods by electron spin resonance

    International Nuclear Information System (INIS)

    Saint-Lebe, L.; Raffi, J.

    1986-11-01

    Principles and conditions required for using electron spin resonance (ESR) in identifying irradiated foods are first put forth. After a literature review, examples of irradiated cereals and French prunes are described in order to derive general conclusions concerning the future of ESR in this field

  11. Influence of electron beam irradiation on the impact properties of polystyrene/EPDM rubber blends

    NARCIS (Netherlands)

    Gisbergen, van J.G.M.; Sanden, van der M.C.M.; Haan, de J.W.; Ven, van de L.J.M.; Lemstra, P.J.

    1991-01-01

    The influence of electron beam (EB) irradiation on the impact properties of compatibilized polystyrene/ethylene-propylene-diene-monomer (PSIEPDM) blends was studied. The change in impact value upon irradiation proved to be strongly dependent on the type of compatibilizer used. Using a

  12. Polymerization of polyethers initiated by irradiation with high power pulsed electron beams

    International Nuclear Information System (INIS)

    Gerber, V.D.; Tolkachev, V.S.; Chmukh, V.N.

    1982-01-01

    Air oxygen effect on thin-layer polymerization of polyethers, initiated by irradiation with powerful pulse electron beams is studied using the method of IR-spectrophotometry. The analysis of experimental data has shown that in polyether surface layer polymerization is suppressed by oxygen, concentration of which in the layer remains stable at the expense of diffusion from air during two consequent irradiation pulses

  13. Polarization of electron-beam irradiated LDPE films: contribution to charge generation and transport

    Science.gov (United States)

    Banda, M. E.; Griseri, V.; Teyssèdre, G.; Le Roy, S.

    2018-04-01

    Electron-beam irradiation is an alternative way to generate charges in insulating materials, at controlled position and quantity, in order to monitor their behaviour in regard to transport phenomena under the space charge induced electric field or external field applied. In this study, low density polyethylene (LDPE) films were irradiated by a 80 keV electron-beam with a flux of 1 nA cm‑2 during 10 min in an irradiation chamber under vacuum conditions, and were then characterized outside the chamber using three experimental methods. The electrical behaviour of the irradiated material was assessed by space charge measurements using the pulsed electro-acoustic (PEA) method under dc stress. The influence of the applied electric field polarity and amplitude has been tested in order to better understand the charge behaviour after electron-beam irradiation. Fourier transform infra-red spectroscopy (FTIR) and photoluminescence (PL) measurements were performed to evaluate the impact of the electron beam irradiation, i.e. deposited charges and energy, on the chemical structure of the irradiated samples. The present results show that the electrical behaviour in LDPE after irradiation is mostly driven by charges, i.e. by physical process functions of the electric field, and that changes in the chemical structure seems to be mild.

  14. Effect of Gamma and Electron Beam Irradiation on Textile Waste Water

    International Nuclear Information System (INIS)

    Selambakkannu, S.; Khomsaton Abu Bakar; Ting, T.M.

    2011-01-01

    In this studies gamma and electron beam irradiation was used to treat textile waste water. Comparisons between both types of irradiation in terms of effectiveness to degrade the pollutants present in textile waste water was done. Prior to irradiation, the raw wastewater was diluted using distilled water to a target concentration of COD 400 mg/l. The sample was irradiated at selected doses between the ranges of 10 kGy to 100 kGy. The results showed that irradiation has significantly contributed in the reduction of the highly colored refractory organic pollutants. The COD removal at the lowest dose, 10 kGy, was reduced to 390 mg/l for gamma and 400 mg/l for electron beam. Meanwhile, at the highest dose, 100 kGy, the COD was reduced to 125 mg/l for gamma and 144 mg/l for electron beam. The degree of removal is influenced by the dose introduced during the treatment process. As the dose increased, the higher the removal of organic pollutant was recorded. However, gamma irradiation is more effective although the differences are not significant between gamma and electron beam irradiation. On the other hand, other properties of the wastewater such as pH, turbidity, suspended solid, BOD and color also shows a gradual decrease as the dose increases for both types of irradiation. (author)

  15. Electrical properties of irradiated PVA film by using ion/electron beam

    Science.gov (United States)

    Abdelrahman, M. M.; Osman, M.; Hashhash, A.

    2016-02-01

    Ion/electron beam bombardment has shown great potential for improving the surface properties of polymers. Low-energy charged (ion/electron) beam irradiation of polymers is a good technique to modify properties such as electrical conductivity, structural behavior, and their mechanical properties. This paper reports on the effect of nitrogen and electron beam irradiation on the electrical properties of polyvinyl alcohol (PVA) films. PVA films of 4 mm were exposed to a charged (ion/electron) beam for different treatment times (15, 30, and 60 minutes); the beam was produced from a dual beam source using nitrogen gas with the other ion/electron source parameters optimized. The dielectric loss tangent tan δ , electrical conductivity σ , and dielectric constant ɛ ^' } in the frequency range 100 Hz-100 kHz were measured at room temperature. The variation of dielectric constant and loss tangent as a function of frequency was also studied at room temperature. The dielectric constant was found to be strongly dependent on frequency for both ion and electron beam irradiation doses. The real (ɛ ^' }) and imaginary (ɛ ^' ' }) parts of the dielectric constant decreased with frequency for all irradiated and non-irradiated samples. The AC conductivity showed an increase with frequency for all samples under the influence of both ion and electron irradiation for different times. Photoluminescence (PL) spectral changes were also studied. The formation of clusters and defects (which serve as non-radiative centers on the polymer surface) is confirmed by the decrease in the PL intensity.

  16. Irradiation-related amorphization and crystallization: In situ transmission electron microscope studies

    International Nuclear Information System (INIS)

    Allen, C.W.

    1994-01-01

    Interfacing an ion accelerator to a transmission electron microscope (TEM) allows the analytical functions of TEM imaging and diffraction to be employed during ion-irradiation effects studies. At present there are twelve such installations in Japan, one in France and one in the US. This paper treats several aspects of in situ studies involving electron and ion beam induced and enhanced phase transformations and presents results of several in situ experiments to illustrate the dynamics of this approach in the materials science of irradiation effects. The paper describes the ion- and electron-induced amorphization of CuTi; the ion-irradiation-enhanced transformation of TiCr 2 ; and the ion- and electron-irradiation-enhanced crystallization of CoSi 2

  17. Temperature and 8 MeV electron irradiation effects on GaAs solar cells

    Indian Academy of Sciences (India)

    1Department of Physics, Mangalore Institute of Technology and Engineering, ... strate were irradiated with 1 MeV electrons, they showed high radiation tolerance ... under both forward and reverse bias in the temperature range of 270–315 K ...

  18. Correlation between electron-irradiation defects and applied stress in graphene: A molecular dynamics study

    Energy Technology Data Exchange (ETDEWEB)

    Kida, Shogo; Yamamoto, Masaya; Kawata, Hiroaki; Hirai, Yoshihiko; Yasuda, Masaaki, E-mail: yasuda@pe.osakafu-u.ac.jp [Department of Physics and Electronics, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Tada, Kazuhiro [Department of Electrical and Control Systems Engineering, National Institute of Technology, Toyama College, Toyama 939-8630 (Japan)

    2015-09-15

    Molecular dynamics (MD) simulations are performed to study the correlation between electron irradiation defects and applied stress in graphene. The electron irradiation effect is introduced by the binary collision model in the MD simulation. By applying a tensile stress to graphene, the number of adatom-vacancy (AV) and Stone–Wales (SW) defects increase under electron irradiation, while the number of single-vacancy defects is not noticeably affected by the applied stress. Both the activation and formation energies of an AV defect and the activation energy of an SW defect decrease when a tensile stress is applied to graphene. Applying tensile stress also relaxes the compression stress associated with SW defect formation. These effects induced by the applied stress cause the increase in AV and SW defect formation under electron irradiation.

  19. Interaction of electron irradiation with nitrogen-related deep levels in InGaAsN

    International Nuclear Information System (INIS)

    Khan, Aurangzeb; Gou, J.; Imazumi, M.; Yamaguchi, M.

    2007-01-01

    The authors present an investigation of 1 MeV electron irradiation-induced defects in p-InGaAsN and their impact on nitrogen-related defects. A hitherto existing nitrogen-related electron trap E1 (0.20 eV) shows a significant increase in concentration after 1 MeV electron irradiation. In addition, 1 MeV electron irradiation induced a hole trap H1 at energy of about 0.75 eV above the valence band. Isothermal annealing analysis indicates that E1 is a complex defect involving an interstitial or a substitutional atom in combination with some other defect, whose concentration is enhanced by irradiation. A correlation exists between the recovery of free carrier concentration and recovery of the E1 center to preradiation concentrations, which indicates the possibility of the E1 as an acceptorlike center

  20. Effects of irradiation and isochronal anneal temperature on hole and electron trapping in MOS devices

    International Nuclear Information System (INIS)

    Fleetwood, D.M.; Winokur, P.S.; Shaneyfelt, M.R.; Riewe, L.C.; Flament, O.; Paillet, P.; Leray, J.L.

    1998-02-01

    Capacitance-voltage and thermally-stimulated-current techniques are used to estimate trapped hole and electron densities in MOS oxides as functions of irradiation and isochronal anneal temperature. Trapped-charge annealing and compensation effects are discussed

  1. Electron ionization and spin polarization control of Fe atom adsorbed graphene irradiated by a femtosecond laser

    International Nuclear Information System (INIS)

    Yu, Dong; Jiang, Lan; Wang, Feng; Li, Xin; Qu, Liangti; Lu, Yongfeng

    2015-01-01

    We investigate the structural properties and ionized spin electrons of an Fe–graphene system, in which the time-dependent density functional theory (TDDFT) within the generalized gradient approximation is used. The electron dynamics, including electron ionization and ionized electron spin polarization, is described for Fe atom adsorbed graphene under femtosecond laser irradiation. The theoretical results show that the electron ionization and ionized electron spin polarization are sensitive to the laser parameters, such as the incident angle and the peak intensity. The spin polarization presents the maximum value under certain laser parameters, which may be used as a source of spin-polarized electrons. - Highlights: • The structural properties of Fe–graphene system are investigated. • The electron dynamics of Fe–graphene system under laser irradiation are described. • The Fe–graphene system may be used as a source of spin-polarized electrons

  2. Void formation in NiTi shape memory alloys by medium-voltage electron irradiation

    International Nuclear Information System (INIS)

    Schlossmacher, P.; Stober, T.

    1995-01-01

    In-situ electron irradiation experiments of NiTi shape memory alloys, using high-voltage transmission electron microscopes, result in amorphization of the intermetallic compound. In all of these experiments high-voltages more than 1.0 MeV had to be applied in order to induce the crystalline-to-amorphous transformation. To their knowledge no irradiation effects of medium-voltage electrons of e.g. 0.5 MeV have been reported in the literature. In this contribution, the authors describe void formation in two different NiTi shape memory alloys, resulting from in-situ electron irradiation, using a 300 kV electron beam in a transmission electron microscope. First evidence is presented that void formation is correlated with the total oxygen content of the alloys

  3. Effects of electron-beam irradiation on HDPE/Brazil nut shell fiber composite

    International Nuclear Information System (INIS)

    Ferreira, Maiara S.; Sartori, Mariana N.; Oliveira, Rene R.; Moura, Esperidiana A.B.

    2013-01-01

    In recent years, research on the replacement of synthetic fibers by natural fibers as reinforcement in thermoplastic composites has increased dramatically due to the advantages of natural fibers, such as low density, low cost, environmental appeal and recyclability. In the present work, the influence of electron-beam irradiation on mechanical properties of HDPE and HDPE/Brazil Nut Shell (Bertholletia excelsa) fiber compositive was investigated. The HDPE composite reinforced with 5% or 10%, by weight of Brazil nut shell fiber powder with particle sizes equal or smaller than 250 μm were obtained by extrusion, using a twin screw extruder. The materials were irradiated at 200 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated specimens tests samples were submitted to mechanical and thermo-mechanical tests, scanning electron microscopy (SEM), X-Ray diffraction (XRD) and sol-gel analysis and the correlation between their properties was discussed. The results showed significant changes in HDPE mechanical and thermo-mechanical properties due to Brazil nut shell fibers addition and electron-beam irradiation. The surface of the cryo fractured composite samples irradiated showed important visual changes which suggest a better fiber-matrix interfacial adhesion, due to irradiation treatment. These results showed that it is possible to get interesting property gains by using waste from renewable sources instead of the traditional ones and electron-beam radiation treatment. (author)

  4. Effects of electron-beam irradiation on HDPE/Brazil nut shell fiber composite

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Maiara S.; Sartori, Mariana N.; Oliveira, Rene R.; Moura, Esperidiana A.B., E-mail: maiara.sferreira@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    In recent years, research on the replacement of synthetic fibers by natural fibers as reinforcement in thermoplastic composites has increased dramatically due to the advantages of natural fibers, such as low density, low cost, environmental appeal and recyclability. In the present work, the influence of electron-beam irradiation on mechanical properties of HDPE and HDPE/Brazil Nut Shell (Bertholletia excelsa) fiber compositive was investigated. The HDPE composite reinforced with 5% or 10%, by weight of Brazil nut shell fiber powder with particle sizes equal or smaller than 250 μm were obtained by extrusion, using a twin screw extruder. The materials were irradiated at 200 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated specimens tests samples were submitted to mechanical and thermo-mechanical tests, scanning electron microscopy (SEM), X-Ray diffraction (XRD) and sol-gel analysis and the correlation between their properties was discussed. The results showed significant changes in HDPE mechanical and thermo-mechanical properties due to Brazil nut shell fibers addition and electron-beam irradiation. The surface of the cryo fractured composite samples irradiated showed important visual changes which suggest a better fiber-matrix interfacial adhesion, due to irradiation treatment. These results showed that it is possible to get interesting property gains by using waste from renewable sources instead of the traditional ones and electron-beam radiation treatment. (author)

  5. Pollen reference collection digitization

    NARCIS (Netherlands)

    Ercan, F.E.Z.; Donders, T.H.; Bijl, P.K.; Wagner, F.

    2016-01-01

    The extensive Utrecht University pollen reference collection holds thousands of pollen samples of many species and genera from all over the world and has been a basis for the widely-used North West European Pollen Flora. These samples are fixed on glass slides for microscopy use, but the aging

  6. Electron-trapping probability in natural dosemeters as a function of irradiation temperature

    DEFF Research Database (Denmark)

    Wallinga, J.; Murray, A.S.; Wintle, A.G.

    2002-01-01

    The electron-trapping probability in OSL traps as a function of irradiation temperature is investigated for sedimentary quartz and feldspar. A dependency was found for both minerals; this phenomenon could give rise to errors in dose estimation when the irradiation temperature used in laboratory...... procedures is different from that in the natural environment. No evidence was found for the existence of shallow trap saturation effects that Could give rise to a dose-rate dependency of electron trapping....

  7. Dielectric properties of electron irradiated PbZrO 3 thin films

    Indian Academy of Sciences (India)

    The present paper deals with the study of the effects of electron (8 MeV) irradiation on the dielectric and ferroelectric properties of PbZrO3 thin films grown by sol–gel technique. The films were (0.62 m thick) subjected to electron irradiation using Microtron accelerator (delivered dose 80, 100, 120 kGy). The films were well ...

  8. Calibration of thin-film dosimeters irradiated with 80-120 kev electrons

    DEFF Research Database (Denmark)

    Helt-Hansen, J.; Miller, A.; McEwen, M.

    2004-01-01

    A method for calibration of thin-film dosimeters irradiated with 80-120keV electrons has been developed. The method is based on measurement of dose with a totally absorbing graphite calorimeter, and conversion of dose in the graphite calorimeter to dose in the film dosimeter by Monte Carlo calcul......V electron irradiation. The two calibrations were found to be equal within the estimated uncertainties of +/-10% at 1 s.d. (C) 2004 Elsevier Ltd. All rights reserved....

  9. Treatment of toxic gases SO2 and NO X by electron beam irradiation

    International Nuclear Information System (INIS)

    Castro Rubio Poli, D. de; Vieira, J.M.; Campos, C.A. de.

    1993-01-01

    The removal of S O 2 and N O x by electron beam irradiation will be studied using a small scale flow system which is being set up in order to obtain basic data for the process technical and economical feasibility concerning industrial applications. The gas irradiation will be performed using a Electron Beam Accelerator with 1,5 MeV power, 25 m A current from Radiation Dynamics, Inc. USA. (author)

  10. Dose characteristics of total-skin electron-beam irradiation with six-dual electron fields

    International Nuclear Information System (INIS)

    Choi, Tae Jin; Kim, Jin Hee; Kim, Ok Bae

    1998-01-01

    To obtain the uniform dose at limited depth to entire surface of the body, the dose characteristics of degraded electron beam of the large target-skin distance and the dose distribution of the six-dual electron fields were investigated. The experimental dose distributions included the depth dose curve, spatial dose and attenuated electron beam were determined with 300 cm of Target-Skin Distance (TSD) and full collimator size (35x35 cm 2 on TSD 100 cm) in 4 MeV electron beam energy. Actual collimated field size of 105 cmx105 cm at the distance of 300 cm could include entire hemibody. A patient was standing on step board with hands up and holding the pole to stabilize his/her positions for the six-dual fields technique. As a scatter-degrader, 0.5 cm of acrylic plate was inserted at 20 cm from the body surface on the electron beam path to induce ray scattering and to increase the skin dose. The Full Width at Half Maximum(FWHM) of dose profile was 130 cm in large field of 105x105 cm 2 . The width of 100±10% of the resultant dose from two adjacent fields which were separated at 25 cm from field edge for obtaining the dose uniformity was extended to 186 cm. The depth of maximum dose lies at 5 mm and the 80% depth dose lies between 7 and 8 mm for the degraded electron beam by using the 0.5 cm thickness of acrylic absorber. Total skin electron beam irradiation (TSEBI) was carried out using the six dual fields has been developed at Stanford University. The dose distribution in TSEBI showed relatively uniform around the flat region of skin except the protruding and deeply curvatured portion of the body, which showed excess of dose at the former and less dose at the latter. The percent depth dose, profile curves and superimposed dose distribution were investigated using the degraded using the degraded electron beam through the beam absorber. The dose distribution obtained by experiments of TSEBI showed within±10% difference excepts the protruding area of skin which needs a

  11. A low temperature cryostat with a refrigerator for studying electron irradiation effects on solids

    International Nuclear Information System (INIS)

    Oka, Takashi; Yoshida, Toshio; Kitagawa, Michiharu; Yanai, Masayoshi

    1976-01-01

    A low temperature cryostat with a small cryogenic refrigerator is described which is convenient for studying irradiation effects of the energetic electrons on solids. It allows a sample to be kept about 12 K without irradiation and 15 K under the irradiation at a heating rate of 1.5 w. The sample temperature can be changed up to room temperature by adjusting the power of an attached heater and the pressure of a compressor for the refrigerator. The optical and electrical properties of the sample can be measured under and after irradiation. (auth.)

  12. Electron spin resonance (ESR) studies on irradiated cocoa beans and niger seeds

    International Nuclear Information System (INIS)

    Mangaonkar, S.R.; Natarajan, V.; Sastry, M.D.; Desai, S.R.P.; Kulkarni, P.R.

    1997-01-01

    Electron spin resonance (ESR) spectra of irradiated (10kGy) and unirradiated cocoa beans and niger seeds have been compared. Unirradiated cocoa beans failed to give any ESR signal, whereas after irradiation (10kGy) an ESR signal at g = 2.0042 was observed. However, ESR signals are given by both irradiated and unirradiated niger seeds. The intensity of signal was found to be dose-dependent up to 10kGy for both seeds. The signals were stable up to 180 days in both cases. The results indicate the possibility of using ESR for distinguishing between irradiated and unirradiated cocoa beans but not for niger seeds

  13. 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

  14. Reaction of congo red in water after irradiation by pulsed intense relativistic electron beam

    International Nuclear Information System (INIS)

    Kikuchi, Takashi; Kondo, Hironobu; Sasaki, Toru; Harada, Nob.; Moriwaki, Hiroshi; Nakanishi, Hiromitsu; Imada, Go

    2011-01-01

    The reaction of congo red, a well-known toxic azo dye, occurred after irradiation by a pulsed intense relativistic electron beam (PIREB). An aquation of congo red was irradiated by PIREB (2 MeV, 0.36 kA, 140 ns). After PIREB irradiation, the solution was measured by electrospray ionization-mass spectrometry and liquid chromatography/mass spectrometry. It was found that congo red underwent a reaction (77% conversion after five shots of PIREB irradiation) and the hydroxylated compounds of the dye were observed as reaction products. (author)

  15. A study on displacement of crystalline diffraction peaks in electron-beam irradiated filter paper cellulose

    International Nuclear Information System (INIS)

    Zhou Ruimin; Xiang Qun; Song Jing

    1997-01-01

    It is found that the crystalline diffraction angles of the electron-beam irradiated filter paper cellulose shift regularly when the irradiation dose is increased. The experiments indicate that the molecules between crystalline area and amorphous area in the filter paper cellulose will be degraded by the irradiation and the cellulose molecules in the surface of crystal will come off, thus the microcrystalline dimension will be reduced and the diffraction angle will become smaller. The fact that intensity of the 002 peak for filter paper samples decreases gradually with the increasing storage time can be attributed to the post-irradiation effect

  16. Pollen Flora of Pakistan-LXV, berberidaceae

    International Nuclear Information System (INIS)

    Perveen, A.

    2010-01-01

    Pollen morphology of 12 species representing 2 genera of the family Berberidaceae from Pakistan has been examined by light and scanning electron microscope. Pollen grains usually radially symmetrical, iso polar or apolar, spheroidal or sub-prolate, spiroaperturate rarely colpate (3- more), sexine thicker than nexine. Tectal surface mostly foveolate-fossulate or sub-psilate, often rugulate - reticulate. On the basis of apertutal types and exine ornamentation four distinct pollen types are recognized, viz., Berberis calliobotrys-type, Berberis jaeschkeana-type, Berberis kunawurensis-type and Epimedium elatum-type. (author)

  17. Practical aspects of the pasteurization of sewage sludge by electron irradiation

    International Nuclear Information System (INIS)

    Tauber, M.; Hofmann, E.G.; Offermann, B.P.

    1975-01-01

    Recently the demand for disinfection of sewage sludge has increased. Investigations have shown that the radiation pasteurization of sludge is the most preferable treatment. Up to now most of these investigations have been made with 60 Co radiation sources. However, it is not easy to run an economic and safe process line for the irradiation of sewage sludge with such isotope sources. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. From the standpoint of the limited electron penetration into the material it is desirable to use high-energy electrons (up to 1.5 MeV) whereas from an economic standpoint it may be better to use electrons of lower energies (0.5 to 1 MeV) and to homogenize the sewage sludge to the required thickness. The following parameters must be considered for a commercial process line: effectivity of the electron radiation process; limited penetration of electrons into the material to be irradiated; beam power of electron accelerators required for sewage sludge treatment; safety aspects; economics of the process with regard to electron energy, power and homogenization of the material; and environmental aspects of the installations. The practical aspects of commercial process lines for electron irradiation of sewage sludge and the design of handling equipment are discussed in relation to these parameters. (author)

  18. Thermoluminescent characteristics of CaSO4:Dy+PTFE irradiated with high energy electron beams

    International Nuclear Information System (INIS)

    Alvarez, R.; Rivera, T.; Calderon, J. A.; Jimenez, Y.; Rodriguez, J.; Oviedo, O.; Azorin, J.

    2011-10-01

    In the present work thermoluminescent response of dysprosium doped calcium sulfate embedded in polytetrafluorethylene (CaSO 4 :Dy+PTFE) under high electron beam irradiations from linear accelerator for clinical applications was investigated. The irradiations were carried out using high electron beams (6 to 18 MeV) from a linear accelerator Varian, C linac 2300C/D, for clinical practice purpose. The electron irradiations were obtained by using the water solid in order to guarantee electronic equilibrium conditions. Field shaping for electron beams was obtained with electron cones. Glow curve and other thermoluminescent characteristics of CaSO 4 :Dy+PTFE were conducted under high electron beams irradiations. The thermoluminescent response of the pellets showed and intensity peak centered at around 235 C. Thermoluminescent response of CaSO 4 :Dy+PTFE as a function of high electron absorbed dose showed a linearity in a wide range. To obtain reproducibility characteristic, a set of pellets were exposed repeatedly for the same electron absorbed dose. The results obtained in this study can suggest the applicability of CaSO 4 :Dy+PTFE pellets for high electron beam dosimetry, provided fading is correctly accounted for. (Author)

  19. The effect of electron beam irradiation on lipid oxidation in sausages

    Directory of Open Access Journals (Sweden)

    atefeh yousefi

    2017-09-01

    Full Text Available Introduction: Irradiation treatment is one of the best techniques to extend the shelf-life of meat, without emerging the nutritional properties and sensory quality of irradiated meat products.  However electron -beam  may cause transformations in foods but has been known as to the most easily-applied irradiation technique in food industries. Electron-beam irradiation is an environment friendly, low cost and time effective alternative to other decontamination technologies. Lipid oxidation could produce of irradiated meat. This study aimed at evaluating the state of lipid oxidation of irradiated sausages. Its findings could help the control, improve food safety and quality properties to food industries. Methods: Sausages were purchased in a local supermarket, minced sausages blended for thiobarbituric acid reactive substances (TBARS analysis and divided into 25 g pieces. The samples including one control group and four case groups. Packaged sausage were exposed at doses of 0 (control, 1, 2, 3 and 5 kGy and analyzed on various days 0, 5, 10 and 30. Results: Thiobarbituric acid reactive substances (TBARS has increased as time goes on (P<0.05. A significant relationship was observed on different Doses. But, the maximum of TBARS was observed in 3 kGy. Conclusion: Utilizing of Electron-beam irradiation in low doses does not have significant difference on lipid oxidation. Irradiating of meat products by addition of antioxidants can minimize or avoid the development of rancidity.

  20. Application of electron-beam irradiation combined with antioxidants for fermented sausage and its quality characteristic

    International Nuclear Information System (INIS)

    Lim, D.G.; Seol, K.H.; Jeon, H.J.; Jo, C.; Lee, M.

    2008-01-01

    The effects of various doses of electron-beam irradiation on the changes in microbiological attributes of fermented sausage and the combined effect of electron-beam irradiation and various antioxidants on the oxidative stability and sensory properties during cold storage were investigated. Results indicated that 2 kGy of irradiation was the most effective in manufacturing a fermented sausage, and the addition of rosemary extracts was effective in controlling the production of off-flavor and development of lipid oxidation during cold storage

  1. Experimental research on fresh mussel meat irradiated by high-dose electron beam

    International Nuclear Information System (INIS)

    Xiao Lin; Lu Ruifeng; Hu Huachao; Wang Chaoqi; Liu Yanna

    2011-01-01

    The sterilization storage of fresh mussel irradiated high-dose electron beam was studied. From the subjective assessment by the weighted average of the test and other determined parameters, it can be concluded that the flavor of fresh mussel meat sealed canned food irradiated by high-dose electron beam has not been significant affected, and various micro-organisms can be killed effectively, which means that the irradiated fresh mussel meat can be preserved for long-term at room temperature. Therefore the method might resolve the problems induced by traditional frozen preservation methods. (authors)

  2. Vacancy-type defects in electron and proton irradiated II-VI compounds

    International Nuclear Information System (INIS)

    Brunner, S.; Puff, W.; Balogh, A.G.; Baumann, H.

    1997-01-01

    In this contribution, the authors present a study aimed at investigating the basic properties of radiation induced defects in ZnS and ZnO and the influence of the atmosphere on the annealing characteristics of the defects. Positron annihilation experiments (both lifetime and Doppler-broadening measurements) were performed on both single- and polycrystalline samples, irradiated with 3 MeV protons or 1 MeV electrons. For ZnS it was found that both electron and proton irradiation caused significant changes in the positron annihilation characteristics. The annealing of proton irradiated ZnS in air leads to significant oxidation and eventual transformation into ZnO

  3. The reactivity of plant, murine and human genome to electron beam irradiation

    International Nuclear Information System (INIS)

    Gavrila, L.; Usurelu, D.; Radu, I.; Timus, D.

    2005-01-01

    A broad spectrum of chromosomal rearrangements is described in plants (Allium cepa), mouse (Mus musculus domestics) and in humans (Homo sapiens sapiens), following in vivo and in vitro beta irradiation. Irradiations were performed at EAL, using a 2.998 GHz traveling-wave electron accelerator. The primary effect of electron beam irradiation is chromosomal breakage followed up by a variety of chromosomal rearrangements i.e. chromosomal aberrations represented mainly by chromatid gaps, deletions, ring chromosomes, dicentrics, translocations, complex chromosomal interchanges, acentric fragments and double minutes (DM). The clastogenic effects were associated in some instances with cell sterilization (i.e. cell death)

  4. Efficient production of NV colour centres in nanodiamonds using high-energy electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Dantelle, G., E-mail: geraldine.dantelle@polytechnique.ed [Laboratoire de Physique Quantique et Moleculaire, ENS Cachan, 94 235 CACHAN Cedex (France); Laboratoire de Physique de la Matiere Condensee, Ecole Polytechnique, 91128 PALAISEAU Cedex (France); Slablab, A.; Rondin, L. [Laboratoire de Physique Quantique et Moleculaire, ENS Cachan, 94 235 CACHAN Cedex (France); Laine, F.; Carrel, F.; Bergonzo, Ph. [CEA-LIST, CEA/Saclay, 91 191 GIF-SUR-YVETTE Cedex (France); Perruchas, S.; Gacoin, T. [Laboratoire de Physique de la Matiere Condensee, Ecole Polytechnique, 91128 PALAISEAU Cedex (France); Treussart, F.; Roch, J.-F. [Laboratoire de Physique Quantique et Moleculaire, ENS Cachan, 94 235 CACHAN Cedex (France)

    2010-09-15

    Nanodiamond powders with an average size of 50 nm have been irradiated using high-energy electron beam. After annealing and chemical treatment, nanodiamond colloidal solutions were obtained and deposited on silica coverslips by spin-coating. The fluorescence of nanodiamonds was studied by confocal microscopy together with atomic force microscopy. We evaluated the proportion of luminescent nanodiamonds as a function of the irradiation duration and showed that large quantities, exceeding hundreds of mg, of luminescent nanodiamonds can be produced within 1 h of electron irradiation.

  5. Efficient production of NV colour centres in nanodiamonds using high-energy electron irradiation

    International Nuclear Information System (INIS)

    Dantelle, G.; Slablab, A.; Rondin, L.; Laine, F.; Carrel, F.; Bergonzo, Ph.; Perruchas, S.; Gacoin, T.; Treussart, F.; Roch, J.-F.

    2010-01-01

    Nanodiamond powders with an average size of 50 nm have been irradiated using high-energy electron beam. After annealing and chemical treatment, nanodiamond colloidal solutions were obtained and deposited on silica coverslips by spin-coating. The fluorescence of nanodiamonds was studied by confocal microscopy together with atomic force microscopy. We evaluated the proportion of luminescent nanodiamonds as a function of the irradiation duration and showed that large quantities, exceeding hundreds of mg, of luminescent nanodiamonds can be produced within 1 h of electron irradiation.

  6. Application of electron-beam irradiation combined with antioxidants for fermented sausage and its quality characteristic

    Science.gov (United States)

    Lim, D. G.; Seol, K. H.; Jeon, H. J.; Jo, C.; Lee, M.

    2008-06-01

    The effects of various doses of electron-beam irradiation on the changes in microbiological attributes of fermented sausage and the combined effect of electron-beam irradiation and various antioxidants on the oxidative stability and sensory properties during cold storage were investigated. Results indicated that 2 kGy of irradiation was the most effective in manufacturing a fermented sausage, and the addition of rosemary extracts was effective in controlling the production of off-flavor and development of lipid oxidation during cold storage.

  7. Effects of high-energy electron irradiation of chicken meat on Salmonella and aerobic plate count

    International Nuclear Information System (INIS)

    Heath, J.L.; Owens, S.L.; Tesch, S.; Hannah, K.W.

    1990-01-01

    Four experiments were used to determine the effects of high-energy irradiation on the number of aerobic microorganisms and Salmonella on broiler breasts and thighs. Irradiation ranging from 100 to 700 kilorads (krads) was provided by a commercial-scale, electron-beam accelerator. Irradiation of broiler breast and thigh pieces with electron beams at levels of 100, 200, 300, 400, 500, and 600 krads showed that levels as low as 100 krads would eliminate Salmonella. When 33 thighs were tested after irradiation at 200 krads, only one thigh tested presumptive positive. The total number of aerobic organisms was reduced by 2 to 3 log10 cycles at irradiation levels of 100, 200, 300, 400, 500, 600, and 700 krads. Increasing the dose above 100 krads gave little if any additional benefit

  8. Analysis of electron spin resonance spectra of irradiated gingers: Organic radical components derived from carbohydrates

    International Nuclear Information System (INIS)

    Yamaoki, Rumi; Kimura, Shojiro; Ohta, Masatoshi

    2010-01-01

    Electron spin resonance (ESR) spectral characterizations of gingers irradiated with electron beam were studied. Complex asymmetrical spectra (near g=2.005) with major spectral components (line width=2.4 mT) and minor signals (at 6 mT apart) were observed in irradiated gingers. The spectral intensity decreased considerably 30 days after irradiation, and continued to decrease steadily thereafter. The spectra simulated on the basis of characteristics of free radical components derived from carbohydrates in gingers are in good agreement with the observed spectra. Analysis showed that shortly after irradiation the major radical components of gingers were composed of radical species derived from amylose and cellulose, and the amylose radicals subsequently decreased considerably. At 30 days after irradiation, the major radical components of gingers were composed of radical species derived from cellulose, glucose, fructose or sucrose.

  9. Engineering of electronic properties of single layer graphene by swift heavy ion irradiation

    Science.gov (United States)

    Kumar, Sunil; Kumar, Ashish; Tripathi, Ambuj; Tyagi, Chetna; Avasthi, D. K.

    2018-04-01

    In this work, swift heavy ion irradiation induced effects on the electrical properties of single layer graphene are reported. The modulation in minimum conductivity point in graphene with in-situ electrical measurement during ion irradiation was studied. It is found that the resistance of graphene layer decreases at lower fluences up to 3 × 1011 ions/cm2, which is accompanied by the five-fold increase in electron and hole mobilities. The ion irradiation induced increase in electron and hole mobilities at lower fluence up to 1 × 1011 ions/cm2 is verified by separate Hall measurements on another irradiated graphene sample at the selected fluence. In contrast to the adverse effects of irradiation on the electrical properties of materials, we have found improvement in electrical mobility after irradiation. The increment in mobility is explained by considering the defect annealing in graphene after irradiation at a lower fluence regime. The modification in carrier density after irradiation is also observed. Based on findings of the present work, we suggest ion beam irradiation as a useful tool for tuning of the electrical properties of graphene.

  10. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    Science.gov (United States)

    Taghinejad-Roudbaneh, M.; Ebrahimi, S. R.; Azizi, S.; Shawrang, P.

    2010-12-01

    The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased ( Pruminal degradation and reducing antinutritional factors of irradiated canola meal.

  11. Dynamic investigation of electron trapping and charge decay in electron-irradiated Al sub 2 O sub 3 in a scanning electron microscope: Methodology and mechanisms

    CERN Document Server

    Fakhfakh, S; Belhaj, M; Fakhfakh, Z; Kallel, A; Rau, E I

    2002-01-01

    The charging and discharging of polycrystalline Al sub 2 O sub 3 submitted to electron-irradiation in a scanning electron microscope (SEM) are investigated by means of the displacement current method. To circumvent experimental shortcomings inherent to the use of the basic sample holder, a redesign of the latter is proposed and tests are carried out to verify its operation. The effects of the primary beam accelerating voltage on charging, flashover and discharging phenomena during and after electron-irradiation are studied. The experimental results are then analyzed. In particular, the divergence between the experimental data and those predicted by the total electron emission yield approach (TEEYA) is discussed. A partial discharge was observed immediately after the end of the electron-irradiation exposure. The experimental data suggests, that the discharge is due to the evacuation to the ground, along the insulator surface, of released electrons from shallow traps at (or in the close vicinity of) the insulat...

  12. Effect of electron beam irradiation on the nutritional ingredient of Sciaenops ocellatus meat

    International Nuclear Information System (INIS)

    Zhang Chunfang; Yang Wenge; Xu Dalun; Shi Huidong

    2011-01-01

    The influences of electron beam irradiation and package pattern (vacuum or ordinary) on the nutritional ingredient of Sciaenops ocellatus meat were investigated. The results were summarized as follows: (1) Electron-beam irradiation dose had notable effect on the moisture content, but no significant impact on the content of ash, protein, lipid and total carbohydrate. Teh package pattern had no significant effect on the common nutrional composition of Sciaenops ocellatus meat. (2) Either package pattern or irradiation dose showed little influence on the total amino acids, delicious amino acid, EAA/TAA and EAA/NEAA of Sciaenops ocellatus meat. The first limiting amino acid of Sciaenops ocellatus meat changed from Met plus Cys to Val in virtue of electron beam irradiation. (3) Both irradiation dose and package pattern showed no difference to the total fatty acid content. But the irradiation dose had notable effect on the relative content of unsaturated fatty acid, polyunsaturated fatty acid and DHA. The vacuum-packaged group had less DHA loss than the ordinary-packaged group with the same absorbed dose, and low dose groups had less DHA loss than the high groups. As conclusion, combining with the bactericidal effect of electron beam irradiation to Sciaenops ocellatus meat, the recommended dose has been proposed to be 3-5 kGy. (authors)

  13. Monte Carlo study of electron irradiation effect on YBCO dpa profiles

    International Nuclear Information System (INIS)

    Pinnera, I.; Cruz, C.; Abreu, Y.; Leyva, A.; Van Espen, P.

    2011-01-01

    The Monte Carlo assisted Classical Method (MCCM) consists on a calculation procedure for determining the displacements per atom (dpa) distribution in solid materials. This algorithm allows studying the gamma and electron irradiation damage in different materials. It is based on the electrons elastic scattering classic theories and the use of Monte Carlo simulation for the physical processes involved. The present study deals with the Monte Carlo simulation of electron irradiation effects on YBa 2 Cu 3 O 7-x (YBCO) slabs using the MCNPX code system. Displacements per atom distributions are obtained through the MCCM for electron irradiation up to 10 MeV. In-depth dpa profiles for electrons and positrons are obtained and analyzed. Also, for each atomic species in the material, the dpa distributions are calculated. All the results are discussed in the present contribution. (Author)

  14. Detection of irradiated deboned turkey meat using electron spin resonance spectroscopy

    International Nuclear Information System (INIS)

    Gray, Richard; Stevenson, M.H.

    1989-01-01

    Bone fragments were extracted from two blocks of frozen deboned turkey meat (irradiated and non-irradiated) using alcoholic KOH digestion. Electron spin resonance (ESR) spectroscopy was used to differentiate between the samples. Comparison of an alcoholic KOH digestion procedure with a freeze drying and grinding method showed that the former method gave a signal which was 78% of that obtained using the freeze drying procedure. Regression analysis of the results obtained after subjection of the original non-irradiated sample to irradiation doses of 3.0, 5.0 and 7.0 kGy gave a linear relationship between irradiation dose and ESR signal strength over this range. Using this relationship the estimated mean dose received by the irradiated block was 4.72 kGy. (author)

  15. Identification of irradiated peppers by electron spin resonance, thermoluminescence and viscosity

    International Nuclear Information System (INIS)

    Polonia, I.; Esteves, M.P.; Andrade, M.E.; Laboratorio Nacional de Engenharia e Tecnologia Industrial, Sacavem; Empis, J.

    1995-01-01

    White and black pepper purchased in local retailers were analysed by electron spin resonance (ESR), thermoluminescence (TL) and viscosimetry (VISC) in order to establish a viable method for identifying possibly irradiated peppers. Samples studied were non irradiated or irradiated in a cobalt-60 plant with the absorbed doses of 3, 5, 7 and 10 kGy. Confirming the data found in the literature TL was revealed by our results the best method to identify irradiated peppers. Nevertheless, the dose received by the samples could not be estimated. The ESR signal of irradiated peppers is similar to the spectrum of cellulose radical but very short lived at ambient temperature. The study on the alteration of viscosity of heat-treated alkaline pepper suspensions indicate that VISC is a very promising method for detection of irradiated peppers. (Author)

  16. Crystalline structure of polypropylene in blends with thermoplastic elastomers after electron beam irradiation

    International Nuclear Information System (INIS)

    Steller, Ryszard; Zuchowska, Danuta; Meissner, Wanda; Paukszta, Dominik; Garbarczyk, Jozef

    2006-01-01

    Isotactic polypropylene (PP) was blended in extruder with 0-50% addition of styrene-ethylene/butylene-styrene (SEBS) and styrene-butadiene-styrene (SBS) block copolymers. Granulated blends were irradiated with electron beam (60 kGy) and 1 week later processed with injection molding machine. Properties of samples molded from irradiated and non-irradiated granulates were investigated using DSC, WAXS, MFR, SEM and mechanical and solubility tests. It was found that the SEBS based systems are more resistant to irradiation in comparison to similar blends with SBS copolymer. Such behavior can be explained by the presence of double bonds in elastic SBS block. Irradiation of PP-SBS blends leads to considerable structure changes of crystalline and amorphous PP phases and elastic SBS phase. It indicates creation of new (inter)phase consisting of products of grafting and cross-linking reactions. Irradiated PP-SBS blends show significant improvement of impact strength at low temperatures

  17. Vacancy defects in electron irradiated RPV steels studied by positron lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Moser, P; Li, X H [CEA Centre d` Etudes de Grenoble, 38 (France). Dept. de Recherche Fondamentale sur la Matiere Condensee; Akamatsu, M; Van Duysen, J C [Electricite de France (EDF), 77 - Ecuelles (France)

    1994-12-31

    Specimens of French RPV (reactor pressure vessels) steels at different rates of segregation have been irradiated at 150 and 288 deg C with 3 MeV electrons (irradiation dose: 4*10{sup 19} e-/cm{sup 2}). Vacancy defects are studied by positron lifetime measurements before and after irradiation and at each step of isochronal annealing. After 150 deg C irradiation, a recovery step is observed in both specimens, for annealing treatments in the range 220-370 deg C and is attributed to the dissociation of vacancy-impurity complexes. The size of vacancy clusters never overcome 10 empty atomic volumes. If ``fresh`` dislocations are created just before irradiation, big vacancy clusters could be formed. After 288 deg C irradiation, small vacancy cluster of 4-10 empty atomic volumes are observed. (authors). 3 figs., 7 refs.

  18. Analysis of volatile organic compounds of ‘Fuji’ apples following electron beam irradiation and storage

    International Nuclear Information System (INIS)

    Song, Hyun-Pa; Shim, Sung-Lye; Lee, Sun-Im; Kim, Dong-Ho; Kwon, Joong-Ho; Kim, Kyong-Su

    2012-01-01

    The volatile organic compounds of non-irradiated and electron-beam irradiated ‘Fuji’ apples (Malus domestica Borkh.) at 0, 0.5, and 1 kGy were isolated through simultaneous distillation extractions and analyzed using gas chromatograph–mass spectrometry. A total of 53 volatile organic compounds were characterized in 0 and 1 kGy irradiated samples, whereas two more compounds related to ketone and terpenoid group were identified in 0.5 kGy irradiated samples. The contents of volatile compounds were 24.33, 36.49, and 35.28 mg/kg in 0, 0.5, and 1 kGy irradiated samples, respectively. The major compounds identified were butanol, hexanal, [E]-2-hexenal, and hexanol in all samples. The relative content of alcohol increased after 30 days of storage in all samples, whereas that of aldehyde decreased. Although the contents of some volatile compounds were changed by electron-beam irradiation, the total yield and major flavor compounds of irradiated ‘Fuji’ apples were similar to, or even greater than, those of the control. Therefore, the application of e-beam irradiation if required for microbial decontamination of ‘Fuji’ apples is an acceptable method as it does not bring about any major quantitative changes of volatile organic compounds. - Highlights: ► We analyzed the volatile organic compounds of electron beam irradiated Fuji apples. ► The major compounds of samples were butanol, hexanal, [E]-2-hexenal, and hexanol. ► The contents of major flavor compounds of non-irradiated and irradiated samples were similar.

  19. Characterization of blend hydrogels based on plasticized starch/cellulose acetate/carboxymethyl cellulose synthesized by electron beam irradiation

    Science.gov (United States)

    Senna, Magdy M.; Mostafa, Abo El-Khair B.; Mahdy, Sanna R.; El-Naggar, Abdel Wahab M.

    2016-11-01

    Blend hydrogels based on aqueous solutions of plasticized starch and different ratios of cellulose acetate (CA) and carboxymethyl cellulose (CMC) were prepared by electron beam irradiation (EB). The blends before and after EB irradiation were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The physico-chemical properties of blend hydrogels prepared by electron beam irradiation were improved compared to unirradiated blends.

  20. Irradiation detection of coffee mate by electron spin resonance (ESR)

    Energy Technology Data Exchange (ETDEWEB)

    Ozsayin, Fulya [Physics Engineering Department, Hacettepe University, 06800 Ankara (Turkey); Polat, Mustafa, E-mail: polat@hacettepe.edu.t [Physics Engineering Department, Hacettepe University, 06800 Ankara (Turkey)

    2011-06-15

    Un-irradiated coffee mate samples do not exhibit any ESR signal. However, the samples exposed to UV and gamma radiation exhibit an ESR singlet and a large unresolved ESR signal, respectively. The dose-response curves of the samples exposed to UV and gamma radiations were found to be described well by an exponential and linear functions, respectively. Variable temperature and fading studies at room temperature showed that the radiation-induced radicals in coffee mate sample are very sensitive to temperature. The discrimination between un-irradiated and irradiated coffee mate samples can be done just comparing their ESR spectra. However, determination of the radiation dose received by the sample cannot be possible because of the fast decay of signal intensity at room temperature.

  1. 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.

  2. 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.

  3. 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.

  4. Defects in electron irradiated vitreous SiO2 probed by positron annihiliation

    International Nuclear Information System (INIS)

    Uedono, Akira; Tanigawa, Shoichiro; Kawano, Takao; Itoh, Hisayoshi

    1994-01-01

    Defects in 3 MeV electron irradiated vitreous SiO 2 (v-SiO 2 ) were probed by the positron annihilation technique. For unirradiated v-SiO 2 specimens, almost all positrons were found to annihilate from positronium (Ps) states. This high formation probability of Ps was attributed to the trapping of positrons by open-space defects. The formation probability of Ps was decreased by the electron irradiation. The observed inhibition of the Ps formation was attributed to the trapping of positrons by point defects introduced and/or activated by the irradiation. From measurements of the lifetime distribution of Ps, it was found that, by the electron irradiation, the mean size of open-space defects was decreased and the size distribution of such defects was broadened. (Author)

  5. Defects in electron irradiated vitreous SiO[sub 2] probed by positron annihiliation

    Energy Technology Data Exchange (ETDEWEB)

    Uedono, Akira; Tanigawa, Shoichiro (Tsukuba Univ., Ibaraki (Japan). Inst. of Materials Science); Kawano, Takao (Tsukuba Univ., Ibaraki (Japan). Radioisotope Centre); Itoh, Hisayoshi (Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment)

    1994-10-10

    Defects in 3 MeV electron irradiated vitreous SiO[sub 2] (v-SiO[sub 2]) were probed by the positron annihilation technique. For unirradiated v-SiO[sub 2] specimens, almost all positrons were found to annihilate from positronium (Ps) states. This high formation probability of Ps was attributed to the trapping of positrons by open-space defects. The formation probability of Ps was decreased by the electron irradiation. The observed inhibition of the Ps formation was attributed to the trapping of positrons by point defects introduced and/or activated by the irradiation. From measurements of the lifetime distribution of Ps, it was found that, by the electron irradiation, the mean size of open-space defects was decreased and the size distribution of such defects was broadened. (Author).

  6. An experience of electron beam (EB) irradiated gemstones in Malaysian nuclear agency

    Energy Technology Data Exchange (ETDEWEB)

    Idris, Sarada, E-mail: sarada@nuclearmalaysia.gov.my; Hairaldin, Siti Zulaiha, E-mail: sarada@nuclearmalaysia.gov.my; Tajau, Rida, E-mail: sarada@nuclearmalaysia.gov.my; Karim, Jamilah, E-mail: sarada@nuclearmalaysia.gov.my; Jusoh, Suhaimi, E-mail: sarada@nuclearmalaysia.gov.my; Ghazali, Zulkafli, E-mail: sarada@nuclearmalaysia.gov.my [Malaysian Nuclear Agency, Bangi, Selangor (Malaysia); Ahmad, Shamshad [School of Chemicals and Material Engineering, NUST Islamabad (Pakistan)

    2014-02-12

    In Nuclear Malaysia, a study on gemstone irradiation using beta particle is conducted. The purpose of the study is to evaluate the gemstone colour enhancement by using different kind of precious and non-precious gemstones. By using irradiation technique, selected gemstones are exposed to highly ionizing radiation electron beam to knock off electrons to generate colour centres culminating in the introduction of deeper colours. The colour centres may be stable or unstable depending on the nature of colour centre produced. The colour change of irradiated stones were measured by HunterLab colour measurement. At 50 kGy, Topaz shows changes colour from colourless to golden. Meanwhile pearl shows changes from pale colour to grey. Kunzite and amethyst shows colour changes from colorless to green and pale colour to purple. Gamma survey meter measurement confirmed that irradiation treatment with 3 MeV electron beam machine does not render any activation that activate the gems to become radioactive.

  7. An experience of electron beam (EB) irradiated gemstones in Malaysian nuclear agency

    Science.gov (United States)

    Idris, Sarada; Hairaldin, Siti Zulaiha; Tajau, Rida; Karim, Jamilah; Jusoh, Suhaimi; Ghazali, Zulkafli; Ahmad, Shamshad

    2014-02-01

    In Nuclear Malaysia, a study on gemstone irradiation using beta particle is conducted. The purpose of the study is to evaluate the gemstone colour enhancement by using different kind of precious and non-precious gemstones. By using irradiation technique, selected gemstones are exposed to highly ionizing radiation electron beam to knock off electrons to generate colour centres culminating in the introduction of deeper colours. The colour centres may be stable or unstable depending on the nature of colour centre produced. The colour change of irradiated stones were measured by HunterLab colour measurement. At 50 kGy, Topaz shows changes colour from colourless to golden. Meanwhile pearl shows changes from pale colour to grey. Kunzite and amethyst shows colour changes from colorless to green and pale colour to purple. Gamma survey meter measurement confirmed that irradiation treatment with 3 MeV electron beam machine does not render any activation that activate the gems to become radioactive.

  8. Electron beam irradiation crosslinked hydrogels based on tyramine conjugated gum tragacanth.

    Science.gov (United States)

    Tavakol, Moslem; Dehshiri, Saeedeh; Vasheghani-Farahani, Ebrahim

    2016-11-05

    In the present study, electron beam irradiation was applied to prepare a chemically crosslinked hydrogel based on tyramine conjugated gum tragacanth. Then, the gel content, swelling behavior and cytotoxicity of the hydrogels were evaluated. The gel content of the hydrogels was in the range of 75-85%. Equilibrium swelling degree of the hydrogels decreased from 51 to 14 with increasing polymer concentration and irradiation dose. Moisture retention capability of the hydrogels after 5h incubation at 37°C was in the range of 45-52 that is comparable with of commercial hydrogels. The cytotoxicity analysis showed the good biocompatibility of hydrogels. These results indicated that electron beam irradiation is a promising method to prepare chemically crosslinked tyramine conjugated gum tragacanth hydrogels for biomedical applications. Also, the versatility of electron beam irradiation for crosslinking of a variety of polymers possessing tyramine groups was demonstrated. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. An experience of electron beam (EB) irradiated gemstones in Malaysian nuclear agency

    International Nuclear Information System (INIS)

    Idris, Sarada; Hairaldin, Siti Zulaiha; Tajau, Rida; Karim, Jamilah; Jusoh, Suhaimi; Ghazali, Zulkafli; Ahmad, Shamshad

    2014-01-01

    In Nuclear Malaysia, a study on gemstone irradiation using beta particle is conducted. The purpose of the study is to evaluate the gemstone colour enhancement by using different kind of precious and non-precious gemstones. By using irradiation technique, selected gemstones are exposed to highly ionizing radiation electron beam to knock off electrons to generate colour centres culminating in the introduction of deeper colours. The colour centres may be stable or unstable depending on the nature of colour centre produced. The colour change of irradiated stones were measured by HunterLab colour measurement. At 50 kGy, Topaz shows changes colour from colourless to golden. Meanwhile pearl shows changes from pale colour to grey. Kunzite and amethyst shows colour changes from colorless to green and pale colour to purple. Gamma survey meter measurement confirmed that irradiation treatment with 3 MeV electron beam machine does not render any activation that activate the gems to become radioactive

  10. Effect of electron irradiation on gas sensing properties of Al-Zno

    Directory of Open Access Journals (Sweden)

    Sunil C. Vattappalam

    2015-12-01

    Full Text Available Al–ZnO thin films are prepared by Silar method and are annealed at 450°C for 1 h. A selected number of samples are irradiated by high-energy electron beam and all are characterized by XRD, SEM and energy-dispersive X-ray spectroscopy. Both irradiated and non-irradiated samples are then placed independently inside a gas chamber kept at rotary vacuum. The gas chamber is maintained at a pressure of 0.20 mb and at a temperature of 350°C. Ethanol vapour is admitted in a controlled manner into the chamber and the resistance of the film is measured continuously before, during and after the admittance of the ethanol vapour. The experiment is repeated for different dosages of irradiation and different doping concentrations of Al and the resistance of the film getting reduced fast and considerably at the admittance of ethanol has been observed. The response and recovery time of the irradiated samples is compared with that of non-irradiated samples of the same doping concentration. It has been noted that both irradiated and non-irradiated samples show a response time of 1 s and recovery time of the irradiated samples is shorter than that of non-irradiated samples.

  11. Clinical implementation of total skin electron irradiation treatment with a 6 MeV electron beam in high-dose total skin electron mode

    International Nuclear Information System (INIS)

    Lucero, J. F.; Rojas, J. I.

    2016-01-01

    Total skin electron irradiation (TSEI) is a special treatment technique offered by modern radiation oncology facilities, given for the treatment of mycosis fungoides, a rare skin disease, which is type of cutaneous T-cell lymphoma [1]. During treatment the patient’s entire skin is irradiated with a uniform dose. The aim of this work is to present implementation of total skin electron irradiation treatment using IAEA TRS-398 code of practice for absolute dosimetry and taking advantage of the use of radiochromic films.

  12. Clinical implementation of total skin electron irradiation treatment with a 6 MeV electron beam in high-dose total skin electron mode

    Energy Technology Data Exchange (ETDEWEB)

    Lucero, J. F., E-mail: fernando.lucero@hoperadiotherapy.com.gt [Universidad Nacional de Costa Rica, Heredia (Costa Rica); Hope International, Guatemala (Guatemala); Rojas, J. I., E-mail: isaac.rojas@siglo21.cr [Centro Médico Radioterapia Siglo XXI, San José (Costa Rica)

    2016-07-07

    Total skin electron irradiation (TSEI) is a special treatment technique offered by modern radiation oncology facilities, given for the treatment of mycosis fungoides, a rare skin disease, which is type of cutaneous T-cell lymphoma [1]. During treatment the patient’s entire skin is irradiated with a uniform dose. The aim of this work is to present implementation of total skin electron irradiation treatment using IAEA TRS-398 code of practice for absolute dosimetry and taking advantage of the use of radiochromic films.

  13. An investigation of the electron irradiation of graphite in a helium atmosphere using a modified electron microscope

    International Nuclear Information System (INIS)

    Burden, A.P.; Hutchison, J.L.

    1997-01-01

    The behaviour of graphite particles immersed in helium gas and irradiated with an electron-beam has been investigated. Because this treatment was performed in a modified high resolution transmission electron microscope, the rapid morphological and microstructural changes that occurred could be directly observed. The results have implications for future controlled environment microscopy of carbonaceous materials and the characterisation of such microscopes. It is also shown that the processes can provide insight into ion-irradiation induced damage of graphite and the mechanism of fullerene generation. (Author)

  14. Therapeutic effect of bee pollens on acute radiation sickness

    International Nuclear Information System (INIS)

    Wang Mingsuo; Huang Chaoqun; Chen Zhen; Huang Meiying; Jiang Ying; Wang Tao

    1997-09-01

    The therapeutic effect of bee pollens on acute radiation sickness were evaluated by observing the changes in the peripheral white blood cell (PWBC) count, the total activity of superoxide dismutase (SOD) and the levels of lipid peroxides (LPO) in sera of the irradiated rats following P.O. administration of bee pollens. It was found that bee pollens could remarkably help irradiated rats recover from radiation-induced injury. The functions of bee pollens might be summarized as follows: (1) Stimulating Proliferation of PWBC. The PWBC count of the bee pollens group showed no significant difference as compared with the normal control group on the 30 th day postirradiation. (2) Enhancing antioxidative effect of clearing free radicals. The total activity of serum SOD in the bee pollens group increased by 6.48% as compared with the normal control group on the 30 th day after irradiation, and the LPO levels i.e. MDA and POV in sera of the irradiated rats decreased by 54.73% and 21.60% respectively. The result suggests that using bee pollens as antiradiation and health-promoting agents in clinical treatment of acute radiation sickness and during radiotherapy of patients with tumors may has certain practical value. (12 refs., 2 figs., 2 tabs.)

  15. Effects of X-rays on seed setting and pollen tube growth in self-incompatible petunia

    International Nuclear Information System (INIS)

    Gilissen, L.J.W.

    1978-01-01

    The high sensitivity of seed setting and the relative insensitivity of pollen tube growth in the style to X-irradiation of pollen of Petunia hybrida L. indicated that pollen tube growth is independent of activities of the pollen genome. The S-specificity of the pollen grain in relation to incompatibility must, therefore, have built up during maturation of the pollen grain. X-irradiation of styles caused changes in some enzymes essential for basic metabolism, without affecting the pattern of compatible or incompatible pollen tube growth. Compatible and incompatible pollen tube growth in the style appeared to be independent of the metabolic state of the stylar cells and their simultaneous gene-activity. It is suggested that the S-specificity of the style, which is responsible for pollen tube growth regulation, is expressed at a very young stage of flower development. (Auth.)

  16. Quality of 'Climax' blueberries after low dosage electron beam irradiation

    International Nuclear Information System (INIS)

    Miller, W.R.; McDonald, R.E.; McCollum, T.G.; Smittle, B.J.

    1994-01-01

    Fruit of 'Climax' rabbiteye blueberries (Vaccinium ashei Reade) were irradiated by a linear accelerator at 0, 0.25, 0.5, 0.75, 1.0, and 1.25 kGy and evaluated for various quality attributes after storage for 1, 3, 7, or 14 days at 1C plus 2 days at 15C, respectively. Weight loss increased during storage and averaged 4.2% after the final inspection and was not affected by irradiation dosage. About 5% of total berries were decayed after 14 days at 1C, about 6% after the final inspection at 15C, but decay was not affected by the level of irradiation. Electrolyte leakage, skin color, total soluble solids, acidity, and pH were also not affected by irradiation dosage. There was a significant decline in berry firmness, flavor, and texture as dosage increased. Berries treated at 1.0 kGy or above were softer and had lower flavor and texture preference scores than berries treated at lower dosages or nontreated berries

  17. Surface flashover performance of epoxy resin microcomposites improved by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yin; Min, Daomin [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Li, Shengtao, E-mail: stli@mail.xjtu.edu.cn [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Li, Zhen; Xie, Dongri [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Wang, Xuan [Key Laboratory of Engineering Dielectric and its Application, Ministry of Education, Harbin University of Science and Technology, Harbin 150040 (China); Lin, Shengjun [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Pinggao Group Company Ltd., State Grid High Voltage Switchgear Insulation Materials Laboratory, Pingdingshan 467001 (China)

    2017-06-01

    Highlights: • Epoxy resin microcomposites were irradiated by electron beam with energies of 10 and 20 keV. • Surface flashover voltage increase with the increase of electron beam energy. • Both the untreated and irradiated samples have two trap centers, which are labeled as shallow and deep traps. • Deposition energy in epoxy resin microcomposites increases with electron beam energy, and surface trap properties are determined by deposition energy. • The influence of surface conductivity and trap distribution on flashover voltage is discussed. - Abstract: The influencing mechanism of electron beam irradiation on surface flashover of epoxy resin/Al{sub 2}O{sub 3} microcomposite was investigated. Epoxy resin/Al{sub 2}O{sub 3} microcomposite samples with a diameter of 50 mm and a thickness of 1 mm were prepared. The samples were irradiated by electron beam with energies of 10 and 20 keV and a beam current of 5 μA for 5 min. Surface potential decay, surface conduction, and surface flashover properties of untreated and irradiated samples were measured. Both the decay rate of surface potential and surface conductivity decrease with an increase in the energy of electron beam. Meanwhile, surface flashover voltage increase. It was found that both the untreated and irradiated samples have two trap centers, which are labeled as shallow and deep traps. The increase in the energy and density of deep surface traps enhance the ability to capture primary emitted electrons. In addition, the decrease in surface conductivity blocks electron emission at the cathode triple junction. Therefore, electron avalanche at the interface between gas and an insulating material would be suppressed, eventually improving surface flashover voltage of epoxy resin microcomposites.

  18. Electron beam irradiation of simulated diluted sulfurous off-gases from copper smelters

    International Nuclear Information System (INIS)

    Villanueva, L.; Ahumada, L.; Chmielewski, A.G.; Zimek, Z.; Bulka, S.; Licki, J.

    1998-01-01

    An experimental work for the verification of potential use of electron-beam irradiation processing for S O 2 removal from reduced-S O 2 -strength gases, between 1,000 and 10,000 ppm, was conducted in a laboratory unit equipped with a multi-purpose electron accelerator working with beam energy of 800 keV. During experimental tests performed, influence of different operating parameters on the overall S O 2 removal process was established. Tests were conducted under two main conditions, using only electron beam irradiation and using electron beam irradiation plus ammonia injection. Tests results proved the technical feasibility to move S O 2 from off-gases under working experimental conditions, i.e., S O 2 removal is achieved under the two modes of operation. When using only electron beam irradiation S O 2 removal efficiencies found were rather low, up to 40%, but in the case of using electron beam irradiation in conjunction with ammonia injection, it was found that S O 2 removal efficiency raises up to 85% under experimental conditions. (author)

  19. Use of electron spin resonance technique for identifying of irradiated foods

    International Nuclear Information System (INIS)

    El-Shiemy, S.M.E

    2008-01-01

    The present investigation was carried out to establish the electron spin resonance (ESR) technique for identifying of some irradiated foodstuffs, i.e. dried fruits (fig and raisin), nuts (almond and pistachio) and spices (fennel and thyme). Gamma rays were used as follows: 0, 1, 3 and 5 kGy were given for dried fruits, while 0, 2, 4 and 6 kGy were given for nuts. In addition, 0, 5, 10 and 15 kGy were given for spices. All treatments were stored at room temperature (25±2 degree C) for six months to study the possibility of detecting its irradiation treatment by ESR spectroscopy. The obtained results indicated that ESR signal intensities of all irradiated samples were markedly increased correspondingly with irradiation dose as a result of free radicals generated by gamma irradiation. So, all irradiated samples under investigation could be differentiated from unirradiated ones immediately after irradiation treatment. The decay that occur in free radicals which responsible of ESR signals during storage periods at ambient temperature showed a significant minimize in ESR signal intensities of irradiated samples. Therefore, after six months of ambient storage the detection was easily possible for irradiated dried fig with dose ≥ 3 kGy and for all irradiated raisin and pistachio (shell). Also, it was possible for irradiated fennel with dose ≥ 10 kGy and for irradiated thyme with dose ≥15 kGy. In contrast, the identification of all irradiated samples of almond (shell as well as edible part) and pistachio (edible part) was impossible after six months of ambient storage.

  20. Use of electron spin resonance technique for identifying of irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    El-Shiemy, S M E

    2008-07-01

    The present investigation was carried out to establish the electron spin resonance (ESR) technique for identifying of some irradiated foodstuffs, i.e. dried fruits (fig and raisin), nuts (almond and pistachio) and spices (fennel and thyme). Gamma rays were used as follows: 0, 1, 3 and 5 kGy were given for dried fruits, while 0, 2, 4 and 6 kGy were given for nuts. In addition, 0, 5, 10 and 15 kGy were given for spices. All treatments were stored at room temperature (25{+-}2 degree C) for six months to study the possibility of detecting its irradiation treatment by ESR spectroscopy. The obtained results indicated that ESR signal intensities of all irradiated samples were markedly increased correspondingly with irradiation dose as a result of free radicals generated by gamma irradiation. So, all irradiated samples under investigation could be differentiated from unirradiated ones immediately after irradiation treatment. The decay that occur in free radicals which responsible of ESR signals during storage periods at ambient temperature showed a significant minimize in ESR signal intensities of irradiated samples. Therefore, after six months of ambient storage the detection was easily possible for irradiated dried fig with dose {>=} 3 kGy and for all irradiated raisin and pistachio (shell). Also, it was possible for irradiated fennel with dose {>=} 10 kGy and for irradiated thyme with dose {>=}15 kGy. In contrast, the identification of all irradiated samples of almond (shell as well as edible part) and pistachio (edible part) was impossible after six months of ambient storage.

  1. Application of polymers cross-linked by electron beam irradiation to electric wire industry

    International Nuclear Information System (INIS)

    Oda, Eisuke

    1976-01-01

    Applications of the polymers cross-linked by electron beam irradiation to electric wire industry as an example of dully developed utilization are reviewed. The report is divided into five parts, namely 1) radiation sources and irradiation processes, 2) development of crosslinking materials, 3) accumulation of electric charge and accumulation of heat, 4) examples of application, and 5) future prospect. Such a phenomenon as discharge destruction pattern (Lichtenberg figure) must be solved, when cable insulation materials are cross-linked by electron beam irradiation. The measures for preventing the discharge destruction are required, especially when the layers of polyethylene insulation for high voltage cables are irradiated. The accumulation of heat causes the troubles in foaming, degeneration and wire running of high potential cables, when the layers of insulation are thick. Effective promoters for cross-linking must be studied to reduce the radiation dose. The irradiators capable of irradiating wires uniformly are desirable. Electron beam accelerators will be used, as far as the radiation dose of 10 or more Mrad is required for cross-linking irradiation. If the dose of one tenth or less of the above value is required, gamma-ray sources (RI) are rather easily applicable than focused strong beam. The utilization of spent nuclear fuel is desirable. (Iwakiri, K.)

  2. Radiation induced coloring of glasses measured during and after electron irradiation

    International Nuclear Information System (INIS)

    Swyler, K.J.; Hardy, W.H. II; Levy, P.W.

    1975-01-01

    The growth of color centers during irradiation, and the decay after irradiation, were studied in two glasses using recently developed equipment for making optical absorption and luminescence measurements during and after electron irradiation. The glasses studied were NBS 710, a soda-lime silicate glass, and NBS 711, a lead silicate glass. Both glasses exhibit similar coloring characteristics. The radiation-induced absorption spectra consists of a weak gaussian shaped band in the visible, a stronger gaussian band in the ultraviolet, and a band edge ''shift'' which may be accurately approximated by a third gaussian band. For all absorption bands, the color center vs dose (or irradiation time) curves can be accurately resolved into two saturating exponential and one linear component. The decay curves obtained after the irradiation is terminated can be accurately expressed by three exponential components. Coloring and decay curves made at different dose rates indicate that the processes responsible for decay after irradiation and electron hole recombination during irradiation play important roles in determining the rate and extent of coloring. Results are qualitatively in agreement with some very simple kinetic treatments for color center formation. In some, but not all, respects the quantitative agreement is also good. Lastly, the results indicate that it is necessary to make measurements during irradiation to establish the formation kinetics of color centers that are unstable at the bombardment temperature. (U.S.)

  3. Dissociated Structure of Dislocation Loops with Burgers Vector alpha in Electron-Irradiated Cu-Ni

    DEFF Research Database (Denmark)

    Bilde-Sørensen, Jørgen; Leffers, Torben; Barlow, P.

    1977-01-01

    The rectangular dislocation loops with total Burgers vector a100 which are formed in Cu-Ni alloys during 1 MeV electron irradiation at elevated temperatures have been examined by weak-beam electron microscopy. The loop edges were found to take up a Hirth-lock configuration, dissociating into two ...

  4. Dislocation Climb Sources Activated by 1 MeV Electron Irradiation of Copper-Nickel Alloys

    DEFF Research Database (Denmark)

    Barlow, P.; Leffers, Torben

    1977-01-01

    Climb sources emitting dislocation loops are observed in Cu-Ni alloys during irradiation with 1 MeV electrons in a high voltage electron microscope. High source densities are found in alloys containing 5, 10 and 20% Ni, but sources are also observed in alloys containing 1 and 2% Ni. The range of ...

  5. Aspects of space charge theory applied to dielectric under electron beam irradiation

    International Nuclear Information System (INIS)

    Oliveira, L.N. de.

    1975-01-01

    Irradiation of solid dielectric with electron beams has been used as a power full tool in investigations of charge storage and transport in such materials. Some of the results that have been obtained in this area are reviewed and the formulation of a transport equation for excess charge in irradiated insulators is dicussed. This equation is subsequently applied to various experimental set-ups. It is found that space charge effects play an essential role in the establishment of stationary currents in samples subject to quasi-penetrating electron beams. Such effects may, however, be neglected for low electron ranges. Theoretical results are in good agreement with experimental findings by Spear (1955)

  6. Electron and photon emissions from gold nanoparticles irradiated by X-ray photons

    Energy Technology Data Exchange (ETDEWEB)

    Casta, R., E-mail: castaromain@gmail.com, E-mail: romain.casta@irsamc.ups-tlse.fr; Champeaux, J.-P.; Moretto-Capelle, P.; Sence, M.; Cafarelli, P. [Université de Toulouse, UPS, Laboratoire Collisions Agrégats Réactivité, IRSAMC, CNRS, UMR 5589 (France)

    2015-01-15

    In this paper, we develop a totally new probabilistic model for the electron and photon emission of gold nanoparticles irradiated by X-ray photons. This model allows direct applications to recent researches about the radiotherapy enhancement by gold nanoparticles in the context of cancer treatment. Our model uses, in a complete original way, simulated Auger cascade and stopping power to compute electron emission spectra, photon emission spectra and released energy inside the material of gold nanoparticles. It allows us to present new results about the electron and photon emission of gold nanoparticle irradiated by hard X-rays.

  7. Radiation defects in InN irradiated with high-energy electrons

    International Nuclear Information System (INIS)

    Zhivul'ko, V.D.; Mudryj, A.V.; Yakushev, M.V.; Martin, R.; Shaff, V.; Lu, Kh.; Gurskij, A.L.

    2013-01-01

    The influence of high energy (6 MeV, fluencies 10 15 – 10 18 cm -2 ) electron irradiation on the fundamental absorption and luminescence properties of InN thin films which were grown on sapphire substrates by molecular bean epitaxial has been studied. It is found that electron irradiation increases the electron concentration and band gap energy E g of InN. The shift of the band gap energy E g is a manifestation of the Burshtein-Mossa effect. (authors)

  8. Fabrication of carbon layer coated FE-nanoparticles using an electron beam irradiation

    Science.gov (United States)

    Kim, Hyun Bin; Jeun, Joon Pyo; Kang, Phil Hyun; Oh, Seung-Hwan

    2016-01-01

    A novel synthesis of carbon encapsulated Fe nanoparticles was developed in this study. Fe chloride (III) and polyacrylonitrile (PAN) were used as precursors. The crosslinking of PAN molecules and the nucleation of Fe nanoparticles were controlled by the electron beam irradiation dose. Stabilization and carbonization processes were carried out using a vacuum furnace at 275 °C and 1000 °C, respectively. Micro structures were evaluated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Fe nanoparticles were formed with diameters of 100 nm, and the Fe nanoparticles were encapsulated by carbon layers. As the electron beam irradiation dose increased, it was observed that the particle sizes decreased.

  9. Electron irradiation induced reduction of the permittivity in chalcogenide glass (As2S3) thin film

    KAUST Repository

    San Roman Alerigi, Damian; Anjum, Dalaver H.; Zhang, Yaping; Yang, Xiaoming; Ben Slimane, Ahmed; Ng, Tien Khee; Hedhili, Mohamed N.; Alsunaidi, Mohammad; Ooi, Boon S.

    2013-01-01

    In this paper, we investigate the effect of electron beam irradiation on the dielectric properties of As 2 S 3 chalcogenide glass. By means of low-loss electron energy loss spectroscopy, we derive the permittivity function, its dispersive relation, and calculate the refractive index and absorption coefficients under the constant permeability approximation. The measured and calculated results show a heretofore unseen phenomenon: a reduction in the permittivity of ? 40 %. Consequently a reduction of the refractive index of 20%, hence, suggests a conspicuous change in the optical properties of the material under irradiation with a 300 keV electron beam. The plausible physical phenomena leading to these observations are discussed in terms of the homopolar and heteropolar bond dynamics under high energy absorption. The reported phenomena, exhibited by As 2 S 3-thin film, can be crucial for the development of photonics integrated circuits using electron beam irradiation method. © 2013 American Institute of Physics.

  10. Effect of electron beam irradiation on the thermal properties of polycarbonate / polyester blend

    International Nuclear Information System (INIS)

    Zarie, K.A.

    2007-01-01

    The effect of electron beam irradiation on the thermal properties of Bayfol (polycarbonate/polyester blend) solid state nuclear track detector (SSNTD) was investigated. Non-isothermal studies were carried out using thermogravimetric analysis (TGA) and differential thermogravimetric (DTG) to obtain the activation energy of thermal decomposition for Bayfol detector. The thermogravimetric analysis (TGA) indicated that the Bayfol samples were decomposed in one main break down stage. Samples of 250 μm thickness sheets were exposed to electron beam irradiations in the dose range 20-600 KGy. The variation of melting temperatures with the electron dose was determined using differential thermal analysis (DTA). The results indicated that the electron irradiation in the dose range 200-600 KGy decreases the melting temperature of the Bayfol samples and this is most suitable for applications requiring the molding of this polymer at lower temperatures

  11. Study of point defect mobilities in zirconium during electron irradiation in a HVEM

    International Nuclear Information System (INIS)

    Griffiths, M.

    1993-01-01

    A high voltage electron microscope (HVEM) was used to investigate the nature of intrinsic point defects in α-Zr by direct observation of dislocation climb and cavity growth or shrinkage. The material used was Marz-grade Zr that had been pre-irradiated with neutrons at about 740 K in the Dounreay Fast Reactor. Dislocation loops of vacancy character that had been produced during the neutron irradiation were studied by further irradiation with electrons in the HVEM. Growth of the loops was observed at temperatures as low as 230 K, indicating that, under the conditions of the experiment, some vacancy-type defects were mobile in the temperature regime 230 K-300 K. The nature of these defects is unknown. One possibility is that these defects are not intrinsic in nature, but may be vacancy-Fe complexes. In addition to the climb of dislocation loops, c-component network dislocations and cavities were also studied. Basal plane climb of the network dislocations was observed at 573 K, but was not readily apparent at 320 K. This suggests that preferred climb planes (and possibly loop habit planes) are sensitive to temperature. Cavities that were already in the foil after neutron irradiation or were induced by electron irradiation grew along the c-axis and shrank along a-directions during electron irradiation. This radiation-induced shape change of the cavities strongly suggests the existence of a diffusional anisotropy difference between interstitials and vacancies in α-Zr. (Author) 14 figs., 22 refs

  12. Comparative effectiveness of gamma-rays and electron beams in food irradiation

    International Nuclear Information System (INIS)

    Hayashi, Toru

    1991-01-01

    Ionizing radiations which can be used for the treatment of foods are gamma-rays from Co-60 and Cs-137, accelerated electrons from a machine at an energy of 10 MeV or lower and X-rays from a machine at an energy of 5 MeV or lower. The Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food held in 1980 concluded that the foods irradiated at overall average doses up to 10 kGy with the radiation listed above are wholesome for human consumption. While most of the commercial food irradiations are conducted with gamma-rays from Co-60, accelerated electrons are increasingly utilized for treating foods. An important difference between gamma-rays and accelerated electrons is the penetration capacity in materials. The penetration capacity of gamma-rays is much higher than that of accelerated electrons. Another important difference is the dose rate. The dose rates of gamma-rays from commercial Co-60 sources are 1-100 Gy/min, while those of electron beams from electron accelerators are 10 3 -10 6 Gy/s. Ideally a comparison of the effect of different types of ionizing radiation should be carried out at the same dose rate but this has been difficult due to the design of irradiators. It is very difficult to draw a definite conclusion on the difference in the effectiveness in food irradiation between gamma-rays and electron beams based on published data. This chapter deals with as many reports as possible on the comparative effectiveness of gamma-rays and electron beams and on the effect of dose rate on chemical reactions and living organisms, whether or not they demonstrate any dependency of the effect of irradiation on dose rate and type of radiation. (author)

  13. Characterization of an irradiated RERTR-7 fuel plate using transmission electron microscopy

    International Nuclear Information System (INIS)

    Gan, J.; Keiser, D.D. Jr.; Miller, B.D.; Robinson, A.B.; Medvedev, P.

    2010-01-01

    Transmission electron microscopy (TEM) has been used to characterize an irradiated fuel plate with Al-2Si matrix from the Reduced Enrichment Research and Test Reactor RERTR-7 experiment that was irradiated under moderate reactor conditions. The results of this work showed the presence of a bubble superlattice within the U-7Mo grains that accommodated fission gases (e.g., Xe). The presence of this structure helps the U-7Mo exhibit a stable swelling behaviour during irradiation. Furthermore, TEM analysis showed that the Si-rich interaction layers that develop around the fuel particles at the U-7Mo/matrix interface during fuel plate fabrication and irradiation become amorphous during irradiation. An important question that remains to be answered about the irradiation behaviour of U-Mo dispersion fuels is how do more aggressive irradiation conditions affect the behaviour of fission gases within the U-7Mo fuel particles and in the amorphous interaction layers on the microstructural scale that can be characterized using TEM? This paper will discuss the results of TEM analysis that was performed on a sample taken from an irradiated RERTR-7 fuel plate with Al-2Si matrix. This plate was exposed to more aggressive irradiation conditions than the RERTR-6 plate. The microstructural features present within the U-7Mo and the amorphous interaction layers will be discussed. The results of this analysis will be compared to what was observed in the earlier RERTR-6 fuel plate characterization. (author)

  14. Effect of low dose electron beam irradiation on the alteration layer formed during nuclear glass leaching

    Energy Technology Data Exchange (ETDEWEB)

    Mougnaud, S., E-mail: sarah.mougnaud@gmail.com [CEA Marcoule, DEN, DTCD, SECM, BP 17171, 30207 Bagnols-sur-Cèze cedex (France); Tribet, M. [CEA Marcoule, DEN, DTCD, SECM, BP 17171, 30207 Bagnols-sur-Cèze cedex (France); Renault, J.-P. [NIMBE, CNRS, CEA, Université Paris Saclay, CEA Saclay, 91191 Gif-sur-Yvette cedex (France); Jollivet, P. [CEA Marcoule, DEN, DTCD, SECM, BP 17171, 30207 Bagnols-sur-Cèze cedex (France); Panczer, G. [Institut Lumière Matière, UMR 5306, Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex (France); Charpentier, T. [NIMBE, CNRS, CEA, Université Paris Saclay, CEA Saclay, 91191 Gif-sur-Yvette cedex (France); Jégou, C. [CEA Marcoule, DEN, DTCD, SECM, BP 17171, 30207 Bagnols-sur-Cèze cedex (France)

    2016-12-15

    This investigation concerns borosilicate glass leaching mechanisms and the evolution of alteration layer under electron beam irradiation. A simple glass doped with rare earth elements was selected in order to access mechanistic and structural information and better evaluate the effects of irradiation. It was fully leached in initially pure water at 90 °C and at high glass surface area to solution volume ratio (S/V = 20 000 m{sup −1}) in static conditions. Under these conditions, the system quickly reaches the residual alteration rate regime. A small particle size fraction (2–5 μm) was sampled in order to obtain a fairly homogeneous altered material enabling the use of bulk characterization methods. External irradiations with 10 MeV electrons up to a dose of 10 MGy were performed either before or after leaching, to investigate respectively the effect of initial glass irradiation on its alteration behavior and the irradiation stability of the alteration layer. Glass dissolution rate was analyzed by regular leachate samplings and the alteration layer structure was characterized by Raman, luminescence (continuous or time-resolved), and {sup 29}Si MAS NMR and EPR spectroscopy. It was shown that the small initial glass evolutions under irradiation did not induce any modification of the leaching kinetic nor of the structure of the alteration layer. The alteration process seemed to “smooth over” the created defects. Otherwise, the alteration layer and initial glass appeared to have different behaviors under irradiation. No Eu{sup 3+} reduction was detected in the alteration layer after irradiation and the defect creation efficiency was much lower than for initial glass. This can possibly be explained by the protective role of pore water contained in the altered material (∼20%). Moreover, a slight depolymerization of the silicon network of the altered glass under irradiation with electrons was evidenced, whereas in the initial glass it typically

  15. Investigation of the combined effect of neutron irradiation and electron beam exposure on pure tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Van Renterghem, W., E-mail: wvrenter@sckcen.be; Uytdenhouwen, I., E-mail: iuytdenh@sckcen.be

    2016-08-15

    Pure tungsten samples were neutron irradiated in the BR2 reactor of SCK·CEN to fluences of 1.47 × 10{sup 20} n/cm{sup 2} and 4.74 × 10{sup 20} n/cm{sup 2} at 300 °C under Helium atmosphere and exposed to the electron beam of the Judith 1 installation The effect of these treatments on the defect structure was studied with transmission electron microscopy. In the irradiated samples the defect structure in the bulk is compared to the structure at the surface. The neutron irradiation created a large amount of a/2‹111› type dislocation loops forming dislocation rafts. The loop density increased from 8.5 × 10{sup 21}/m³ to 9 × 10{sup 22}/m³ with increasing dose, while the loop size decreased from 5.2 nm to 3.5 nm. The electron beam exposure induced significant annealing of the defects and almost all of the dislocation loops were removed. The number of line dislocations in that area increased as a result of the thermal stresses from the thermal shock. - Highlights: • Neutron irradiated and electron beam exposed tungsten samples were studied with transmission electron microscopy. • Neutron irradiation creates dislocation loops and rafts, while voids are created at higher irradiation dose. • No precipitates of transmutation products were found under these low dose irradiation conditions. • Electron beam exposure annihilates the dislocation loops and rafts.

  16. Ion irradiation of AZO thin films for flexible electronics

    Energy Technology Data Exchange (ETDEWEB)

    Boscarino, Stefano; Torrisi, Giacomo; Crupi, Isodiana [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy); Alberti, Alessandra [CNR-IMM, via Strada VIII 5, 95121 Catania (Italy); Mirabella, Salvatore; Ruffino, Francesco [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy); Terrasi, Antonio, E-mail: antonio.terrasi@ct.infn.it [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy)

    2017-02-01

    Highlights: • Evidence of electrical good quality AZO ultra thin films without thermal annealing. • Evidence of the main role of Oxygen vs. structural parameters in controlling the electrical performances of AZO. • Evidence of the role of the ion irradiation in improving the electrical properties of AZO ultra thin films. • Synthesis of AZO thin films on flexible/plastic substrates with good electrical properties without thermal processes. - Abstract: Aluminum doped Zinc oxide (AZO) is a promising transparent conductor for solar cells, displays and touch-screen technologies. The resistivity of AZO is typically improved by thermal annealing at temperatures not suitable for plastic substrates. Here we present a non-thermal route to improve the electrical and structural properties of AZO by irradiating the TCO films with O{sup +} or Ar{sup +} ion beams (30–350 keV, 3 × 10{sup 15}–3 × 10{sup 16} ions/cm{sup 2}) after the deposition on glass and flexible polyethylene naphthalate (PEN). X-ray diffraction, optical absorption, electrical measurements, Rutherford Backscattering Spectrometry and Atomic Force Microscopy evidenced an increase of the crystalline grain size and a complete relief of the lattice strain upon ion beam irradiation. Indeed, the resistivity of thin AZO films irradiated at room temperature decreased of two orders of magnitude, similarly to a thermal annealing at 400 °C. We also show that the improvement of the electrical properties does not simply depend on the strain or polycrystalline domain size, as often stated in the literature.

  17. In-situ synthesis of Ag nanoparticles by electron beam irradiation

    International Nuclear Information System (INIS)

    Gong, Jiangfeng; Liu, Hongwei; Jiang, Yuwen; Yang, Shaoguang; Liao, Xiaozhou; Liu, Zongwen; Ringer, Simon

    2015-01-01

    Ag nanoparticles were synthesized by electron beam irradiation in the transmission electron microscope chamber at room temperature and the growth mechanism was explored in detail. The sizes of the Ag nanoparticles are controlled by the electron beam current density. Two nanoparticle growth stages were identified. The first growth stage was dominated by the discharging effect, while the second stage was controlled by the heating effect. The nanoparticle synthesis method should be applicable to the synthesis of other metallic nanoparticles. - Highlights: • Ag nanoparticles were synthesized by electron beam irradiation in the transmission electron microscope chamber. • The sizes of the Ag nanoparticles are controlled by the electron beam current density. • The growth mechanism was studied, two growth stages were confirmed. • The first growth stage was dominated by the discharging effect, and the second stage was controlled by the heating effect.

  18. Ion irradiation of AZO thin films for flexible electronics

    Science.gov (United States)

    Boscarino, Stefano; Torrisi, Giacomo; Crupi, Isodiana; Alberti, Alessandra; Mirabella, Salvatore; Ruffino, Francesco; Terrasi, Antonio

    2017-02-01

    Aluminum doped Zinc oxide (AZO) is a promising transparent conductor for solar cells, displays and touch-screen technologies. The resistivity of AZO is typically improved by thermal annealing at temperatures not suitable for plastic substrates. Here we present a non-thermal route to improve the electrical and structural properties of AZO by irradiating the TCO films with O+ or Ar+ ion beams (30-350 keV, 3 × 1015-3 × 1016 ions/cm2) after the deposition on glass and flexible polyethylene naphthalate (PEN). X-ray diffraction, optical absorption, electrical measurements, Rutherford Backscattering Spectrometry and Atomic Force Microscopy evidenced an increase of the crystalline grain size and a complete relief of the lattice strain upon ion beam irradiation. Indeed, the resistivity of thin AZO films irradiated at room temperature decreased of two orders of magnitude, similarly to a thermal annealing at 400 °C. We also show that the improvement of the electrical properties does not simply depend on the strain or polycrystalline domain size, as often stated in the literature.

  19. First application of hemi-body electron beam irradiation for Kaposi sarcoma at the lower extremities.

    Science.gov (United States)

    Platoni, Kalliopi; Diamantopoulos, Stefanos; Dilvoi, Maria; Delinikolas, Panagiotis; Kypraiou, Efrosyni; Efstathopoulos, Efstathios; Kouloulias, Vassilis

    2018-01-01

    Kaposi's sarcoma (KS) is a systemic neoplastic disease that can present cutaneous symptoms and is usually treated with a systematic approach due to its extent. Due to its radiosensitivity, radiotherapy is considered one of its main treatments, for palliation and local control of the skin and mucosal lesions. The aim of this paper was to report the first case of KS treated by hemi-body electron irradiation protocol in Greece. A fractionated 40 Gy hemi-body electron irradiation was prescribed to a 60-year-old male patient with KS at his legs. Dose uniformity was verified on a daily basis by thermoluminescence dosimetry (TLD). The treatment resulted to complete clinical response. Limited irradiation-derived side effects appeared. This is the first case ever to be treated with hemi-body electron irradiation protocol in Greece. To the best of our knowledge, this is also the first time that a single field hemi-body electron beam irradiation at a total skin electron beam (TSEB)-like configuration is reported to be used for KS.

  20. Color center annealing and ageing in electron and ion-irradiated yttria-stabilized zirconia

    International Nuclear Information System (INIS)

    Costantini, Jean-Marc; Beuneu, Francois

    2005-01-01

    We have used X-band electron paramagnetic resonance (EPR) measurements at room-temperature (RT) to study the thermal annealing and RT ageing of color centers induced in yttria-stabilized zirconia (YSZ), i.e. ZrO 2 :Y with 9.5 mol% Y 2 O 3 , by swift electron and ion-irradiations. YSZ single crystals with the orientation were irradiated with 2.5 MeV electrons, and implanted with 100 MeV 13 C ions. Electron and ion beams produce the same two color centers, namely an F + -type center (singly ionized oxygen vacancy) and the so-called T-center (Zr 3+ in a trigonal oxygen local environment) which is also produced by X-ray irradiations. Isochronal annealing was performed in air up to 973 K. For both electron and ion irradiations, the defect densities are plotted versus temperature or time at various fluences. The influence of a thermal treatment at 1373 K of the YSZ single crystals under vacuum prior to the irradiations was also investigated. In these reduced samples, color centers are found to be more stable than in as-received samples. Two kinds of recovery processes are observed depending on fluence and heat treatment

  1. Charging effects of PET under electron beam irradiation in a SEM

    International Nuclear Information System (INIS)

    Jbara, O; Rondot, S; Hadjadj, A; Patat, J M; Fakhfakh, S; Belhaj, M

    2008-01-01

    This paper deals with charge trapping and charge transport of polyethylene terephthalate (PET) polymer subjected to electron irradiation in a scanning electron microscope (SEM). Measurement of displacement current and leakage current using an arrangement adapted to the SEM allows the amount of trapped charge during and after electron irradiation to be determined and the charge mechanisms regulation to be studied. These mechanisms involve several parameters related to the electronic injection, the characteristics of insulator and the effects of the trapped charge itself. The dynamic trapping properties of PET samples are investigated and the time constants of charging are evaluated for various conditions of irradiation. The determination of the trapping cross section for electrons is possible by using the trapping rate at the onset of irradiation. Many physical processes are involved in the charging and discharging mechanisms; among them surface conduction is outlined. Through the control of irradiation conditions, various types of surface discharging (flashover phenomenon) behaviour are also observed. The strength of the electric field initiating surface discharge is estimated.

  2. Gemstone color enhancement by electron beam irradiation-A preliminary study

    International Nuclear Information System (INIS)

    Sarada Idris; Zulkafli Ghazali; Shamshad Ahmad; Mohd Suhaimi Jusoh

    2010-01-01

    Treatment of gemstones has been going on for hundreds of years for enhancing color and clarity of gems devoid of these attributes. Whereas previous practices included fraudulent or otherwise processes to achieve the color enhancement, the ionizing radiation has proven to be a reliable and reproducible technique. Three types of irradiation processes include exposure to gamma radiation, electron beam irradiation and the nuclear power plants. Electron Beam Irradiation of Gemstone is a technique in which a gemstone is exposed to highly ionizing radiation electron beam to knock off electrons to generate color centers culminating in introduction of deeper colors. The color centers may be stable or unstable. Below 9 MeV, normally no radioactivity is introduced in the exposed gems. A study was conducted at Electron Beam Irradiation Centre (Alurtron) for gemstone color enhancement by using different kind of precious gemstones mined in Pakistan and elsewhere. The study shows that EB Irradiation not only enhances the color but also improves the clarity of the gemstones. The treated stones included kunzite tourmaline topaz quartz aquamarine and cultured pearls. Doses ranging from 25 kGy to 200 kGy were employed to assess the influence of doses on color and clarity and to select the optimum doses. The samples used included both the rough and the faceted gems. It is concluded that significant revenue generation is associated with the enhancement of the color in clarity of gemstones which are available at very cheap price in the world market. (author)

  3. Shallow irradiation of vienna sausage by electron beams in preventation of the slime production

    International Nuclear Information System (INIS)

    Watanabe, Hiroshi; Kume, Tamikazu; Ito, Hitoshi; Aoki, Shohei; Sato, Tomotaro

    1975-01-01

    Vienna sausages get spoiled by slime production or putrefaction due to the propagation of microorganisms when stored for 3 to 5 days at 10 deg C. The radiation pasteurization of vienna sausages has mainly been studied with gamma irradiation. The slime of sausages is believed to be microorganisms themselves growing on the surface of the sausages. Pasteurization of the surface of vienna sausages with electron irradiation was thus investigated. The results obtained are as follows: The vienna sausages irradiated with a dose of 0.8 to approximately 1.0 Mrad by 0.5 MeV electrons could be stored without slime production or putrefaction for more than a week at 11 deg C. The effect of pasteurization increased with energy and dose of electrons. However, the changes in the organoleptic qualities of vienna sausages were detected when irradiated with a dose of over 0.7 Mrad by 2.0 MeV electrons. Consequently, the irradiation with a dose of 1.0 Mrad by 1.0 MeV electrons was effectual in lengthening their shelf-life without deterioration of the organoleptic qualities. (author)

  4. Device for irradiation with electron and a magnetic lens for deviation of beams of charged particles, especially electrons

    International Nuclear Information System (INIS)

    Anderberg, B.

    1990-01-01

    An electron beam is sweeping aver the object while this is moved forward. In order to achieve a uniform irradiation and compensate for geometric errors, an additional magnetic lens is located immediately beneath the exposed area. The magnetic lens refract the electron beam in such a manner that the particle trajectories become parallel or slightly convergent after the lens. The lens consists of two parallel permanent bar magnets, preferably laminated magnets. (L.F.)

  5. Optical and electrical properties of some electron and proton irradiated polymers

    International Nuclear Information System (INIS)

    Mishra, R.; Tripathy, S.P.; Sinha, D.; Dwivedi, K.K.; Ghosh, S.; Khathing, D.T.; Mueller, M.; Fink, D.; Chung, W.H.

    2000-01-01

    Ion beam treatment studies have been carried out to investigate the potential for improvements in conductivity properties of the polymers Polytetrafluroethylene (PTFE), Polyimide (PI), Polyethyleneterepthalate (PET) and Polypropylene (PP), after 2 MeV electron and 62 MeV proton irradiation. The shift in optical absorption edges as observed by UV-VIS spectra of the irradiated polymers has been correlated to the optical band-gap using Tauc's expression. A decrease in the optical band-gap has been observed in irradiated PP and PTFE, but no considerable change was found for the optical band-gaps of PET and PI. Further AC conductivity measurements confirmed an increase in conductivity in electron irradiated PP

  6. Evaluation of induced radioactivity in 10 MeV-Electron irradiated spices, (2)

    International Nuclear Information System (INIS)

    Katayama, Tadashi; Furuta, Masakazu; Shibata, Setsuko; Matsunami, Tadao; Ito, Norio; Mizohata, Akira; Toratani, Hirokazu; Takeda, Atsuhiko.

    1994-01-01

    In order to check radioactivity of beta-emmitters produced by (γ, n) reactions which could occur at energies up to 10 MeV, black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy. Beta-rays were counted using a 2π gas flow counter and a liquid scintillation counter. Any induced radioactivity could not be detected in irradiated samples. When inorganic compounds containing the nuclides in the list were artificially added in the samples and were irradiated, the β-activities were detected. From the amount of observed radioactivities of β-emmitters produced in the compounds as photonuclear products, it is concluded that the induced radioactivity in natural samples by 10 MeV-electron irradiation were far smaller than natural radioactivity from 40 K contained in the samples and, hence, its biological effects should be negligible. (author)

  7. Evaluation of induced radioactivity in 10 MeV-electron irradiated spices, (1)

    International Nuclear Information System (INIS)

    Furuta, Masakazu; Katayama, Tadashi; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Shibata, Setsuko; Toratani, Hirokazu; Takeda, Atsuhiko.

    1994-01-01

    Black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electrons from a linear accelerator to a dose of 100 kGy and radioactivity was measured in order to estimate induced radioactivity in the irradiated foods. Induced radioactivity could not be detected significantly by γ-ray spectrometry in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list of photonuclear reactions which could produce radioactivity below 10 MeV. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H 50 according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from 40 K contained in the samples. (author)

  8. Research On Degradation Of Silk Fibroin By Combination Of Electron Beam Irradiation And Hydrothermal Processing

    International Nuclear Information System (INIS)

    Nguyen Thi Kim Lan; Dang Van Phu; Le Anh Quoc; Nguyen Quoc Hien

    2014-01-01

    Silk fibers and silk proteins have been demonstrated to be useful to apply in the textile industry, biomedical, cosmetics, pharmaceuticals. In this study, the effects of electron beam (EB) irradiation combined with hydrothermal processing to the solubility of silk fibroin and generation of soluble silk protein were investigated. The solubility of unirradiated and irradiated fibroin were greater than 80 % when hydrothermal degradation was performed in the sodium hydroxide solution at appropriate concentration of 0.05 M. However, the solubility of irradiated fibroin was greater than that of unirradiated sample. The protein content increased from 0.4617 to 0.6530 mg/mg when irradiation doses increased from 0 to 200 kGy, respectively. The molecular weight of protein was determined by SDS-PAGE method. The characteristics of silk protein were confirmed by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and X-ray diffraction (XRD). (author)

  9. Formation of novel reactive intermediate by electron-laser dual beam irradiation

    International Nuclear Information System (INIS)

    Ishida, Akito; Takamuku, Setsuo

    1992-01-01

    The pulse radiolysis system of the Institute of Scientific and Industrial Research, Osaka University, (ISIR) has been progressed to observe a highly reactive species, which is produced by successive irradiation of electron and laser or of CW-UV-light and electron. The dual beam irradiation system, which consists of the beam synchronization system, the optical alignment, and the measurement system, is described in detail. Dual beam irradiation studies on 2-methylbenzophenone and some compounds with a C=N bond have been carried out by use of this system. Pulse radiolysis of 2-methylbenzophenone in benzene induced formation of an unstable photoenol via the triplet state, which was irradiated by a visible laser pulse to give dihydroanthrone. Pulse radiolysis of syn-benzalaniline and a nitrileylide in 2-methyltetrahydrofuran, which were produced by steady state photoirradiation at low temperature, enabled us to observe their very unstable radical anions. (author)

  10. Pre-feasibility study of electron beam irradiation of fresh water

    International Nuclear Information System (INIS)

    Finshi V, Silvia.

    1997-01-01

    A technical/economic evaluation of electron beam irradiation for the decontamination of liquids in the country is presented. Irradiation of fresh water is evaluated for the production of drinking water as a replacement for chlorine disinfection, which can lead to the formation of tri halo methanes. that are carcinogenic compounds. The technical literature states that the percentage of microorganisms removed by electro beam irradiation is high and similar to that found with chlorine disinfection. From an economic point of view, irradiation technology is not presently competitive as an alternative to conventional chlorination in terms of processing costs (US$0.23/m 3 ) instead of US$0.013/m 3 for conventional chlorination. Nevertheless, irradiation costs decreased sharply when unit costs for the accelerator machine are decreased with a resulting drop in capital costs

  11. Effectiveness of electron beam irradiation in the control of some soilborne pathogens

    International Nuclear Information System (INIS)

    Orlikowski, L.B.; Ptaszek, M.; Migdal, W.; Gryczka, U.

    2011-01-01

    Electron beam (EB) irradiation was tested against Botrytis cinerea, Pythium ultimum and Phytophthora citricola the most dangerous pathogens causing stem and root rot of seedlings, cuttings and older plants. In the laboratory trials cultures of 3 species were irradiated with doses 0 (control), 1.5, 3.0, 4.5 and 6.0 kGy whereas peat was treated with 10, 15 and 25 kGy. P. citricola was the most sensitive species for irradiation. In greenhouse trials 15 kGy irradiation of peat protected chrysanthemum cuttings against B. cinerea and P. ultimum as well as rhododendron young plants against P. citricola. Irradiation of peat did not influence the growth and development of the tested plants. (authors)

  12. Effect of electronic beam irradiation on last instar larvae of lasioderma serricorne fabricius

    International Nuclear Information System (INIS)

    Chen Yuntang; Guo Dongquan; Lu Xiaohua; Zhang Jianwei; Yang Baoan; Du Yueguang; Liu Jiangyu; Tian Zhanjun; Zhang Xiaoyan

    2010-01-01

    The electronic beam irradiation effects on the last instar larvae of cigarette beetle (Lasioderma serricorne Fabricius) in tobacco were studied, and the mortality in 42 days, lethal time, pupation rate, emergence rate and reproductive capacity after irradiation were measured. The results showed that the mortality increased with the increase of irradiation dosage, but the larvae did not dead immediately. The last instar larvae irradiated by the dosages higher than 480 Gy could prevent the development of larvae to adults. No new generation was found after 300 Gy treatment of the last instar larvae. So 300 Gy irradiation could be considered as a suitable dose to prevent the reproduction of cigarette beetle of the last instar larvae in the tobacco. (authors)

  13. Low temperature electron beam irradiation effects on the lactate dehydrogenase activity

    International Nuclear Information System (INIS)

    Catana, D.; Hategan, Alina; Oproiu, C.; Popescu, Alina; Hategan, Dora; Morariu, V. V.

    1998-01-01

    The direct and indirect effects of 5 MeV electron beam irradiation in the range 0-400 Gy at 20 deg. C, -3 deg. C and -196 deg. C on the global enzymatic activity of lactate dehydrogenase (LDH) have been studied. Our results showed a monoexponential decrease in the enzymatic activity of irradiated LDH at all irradiation temperatures independently of direct or indirect action of radiation. The temperature gradient used to lower the temperature of the samples to -196 deg. C drastically influences the results. Our data suggest that freeze-thawing in two steps down to -196 deg. C make LDH insensitive to irradiation, while one step freeze-thawing procedure results in a gradual activity loss with increasing dose irradiation. This data can be interpreted in terms of different conformational changes during the particular freeze-thawing process. (authors)

  14. Effect of electron beam irradiation on post harvest quality of Agaricus bisporus

    International Nuclear Information System (INIS)

    Zhang Juanpin; Xing Zengtao; Bai Bing; Song Weiguo

    2011-01-01

    The effects of electron beam irradiation on fresh-keeping of Agaricus bisporus was studied after sporecarp samples were irradiated at 1.0, 2.0, 3.0 and 4.0 kGy and then stored at 4 degree C for 14d. The contents of water-soluble vitamins, amino acids and sugars were measured. Results showed that the contents of water-soluble sugars, amino acids, and aneurin, lactochrome, nicotinic acid in sporecarp did not significantly change after irradiation. However, asoribic acid was sensitive to irradiation, and the content was significantly reduced 31.1% at the dose of 4.0 kGy. It is concluded that 2 kGy irradiation can effectively prolong the shelf life, and almost no significant effect on the nutrient components of Agaricus bisporus. (authors)

  15. Analysis of electron-irradiated poly-ether ether ketone by X-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Oyabu, Matashige; Kobayashi, Yoshinori; Seguchi, Tadao; Sasuga, Tsuneo; Kudoh, Hisaaki.

    1995-01-01

    Organic polymers used in atomic power plants or space are damaged by ionizing irradiation. Radicals produced by irradiation cause oxidation, chain scission and crosslinking, all of which lead to degradation of the material. In this paper, the surface of electron-irradiated poly-ether ether ketone (PEEK) was studied by X-ray photoelectron spectroscopy (XPS). The irradiation in air was found to oxidize the PEEK surface producing carboxyl groups, the content of which dependant on the dose. Carboxyl groups were not produced in helium gas. Quantitative spectral analysis indicated that the aromatic structure might be decomposed. Some comparison was made between the semicrystalline and amorphous samples. The oxygen content resulting from irradiation, of semicrystalline PEEK increased more than that of amorphous PEEK. (author)

  16. The energy distribution function of excess electrons trapped in the pulse irradiated low density polyethylene (LDPE)

    International Nuclear Information System (INIS)

    Wysocki, S.; Mazurek, L.; Karolczak, S.; Kroh, J.

    1995-01-01

    Distribution function D (E) of electrons trapped in irradiated LDPE was calculated on the basis of time resolved absorption spectra recorded at temperatures of 20-250 K. Variation of absorption spectra with time and temperature were observed and discussed in terms of simultaneous decay and relocation of electrons from shallow to deeper traps. Results obtained imply domination of trap limited transport for shallowly trapped electrons. For deeper traps, hopping mechanism is prevailing. (author)

  17. Economic efficiency analysis of electron accelerator for irradiation processing

    International Nuclear Information System (INIS)

    Shi Huidong; Chen Ronghui

    2003-01-01

    The fixed assets, running cost and economic efficiency were discussed in this paper. For building electron accelerator of 10 MeV and 3 kW, the running cost is one time higher than building cobalt source at 2.22 x 10 15 Bq, but economic efficiency of building a electron accelerator is much higher than building a cobalt source

  18. Effects of gamma and electron beam irradiation on the microbial quality of steamed tofu rolls

    International Nuclear Information System (INIS)

    Jia, Qian; Gao, Meixu; Li, Shurong; Wang, Zhidong

    2013-01-01

    The effectiveness of two kinds of radiation processing, gamma and electron beam (ebeam) irradiation, for the inactivation of Staphylococcus aureus, Salmonella enteritidis and Listeria innocua which were inoculated in pre-sterilised steamed tofu rolls was studied. The corresponding effects of both irradiation types on total bacterial counts (TBCs) in commercial steamed tofu rolls available in the market were also examined. The microbiological results demonstrated that gamma irradiation yielded D 10 values of 0.20, 0.24 and 0.22 kGy for S. aureus, S. enteritidis and L. innocua, respectively. The respective D 10 values for ebeam irradiation were 0.31, 0.35 and 0.27 kGy. Gamma and ebeam irradiation yielded D 10 values of 0.48 and 0.43 kGy for total bacterial counts in commercial steamed tofu rolls, respectively. The results suggest that ebeam irradiation has similar effect on decreasing TBCs in steamed tofu rolls, and gamma irradiation is slightly more effective than ebeam irradiation in reducing the populations of pathogenic bacteria. The observed differences in D 10 -values between them might be due to the significant differences in dose rate applied, and radiation processing of soybean products to improve their microbial quality could be available for other sources of protein. - Highlights: ► Our research material is steamed tofu rolls, a kind of soybean products. ► We compared the effects of gamma ray and electron beam irradiation. ► Total bacterial and three strains of pathogens are studied in our research. ► We reported electron beam has similar decontamination effect as gamma ray. ► Radiation processing of soybean products to improve their microbial quality could be available for other sources of protein.

  19. Effects of electron beam irradiation on the structural properties of polylactic acid/polyethylene blends

    Energy Technology Data Exchange (ETDEWEB)

    Bee, Soo-Tueen, E-mail: direct.beest@gmail.com [Department of Chemical Engineering, Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Genting Kelang, 53300 Setapak, Kuala Lumpur (Malaysia); Ratnam, C.T. [Radiation Processing Technology Division, Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia); Sin, Lee Tin, E-mail: direct.tinsin@gmail.com [Department of Chemical Engineering, Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Genting Kelang, 53300 Setapak, Kuala Lumpur (Malaysia); Tee, Tiam-Ting; Wong, Wai-Kien; Lee, Jiuun-Xiang [Department of Chemical Engineering, Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Genting Kelang, 53300 Setapak, Kuala Lumpur (Malaysia); Rahmat, A.R. [Department of Polymer Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor (Malaysia)

    2014-09-01

    Highlights: •Electron beam irradiation on polyethylene (LDPE) and polylactic acid (PLA) blends. •Irradiated PLA/LDPE blends exhibit structural rearrangement to highly ordered structure. •Irradiated PLA/LDPE matrix extends continuity of polymer matrix with larger fibrils diameter. -- Abstract: The purpose of this research was to investigate the effects of electron beam irradiation on the properties of polylactic acid (PLA) and low density polyethylene (LDPE) blends. The PLA were compounded with 20–80% LDPE and were exposed to electron beam irradiation dosages of 20–120 kGy. The results from gel content and X-ray diffraction analyses showed that the addition of LDPE to PLA effectively increased the gel content and crystallinity. However, an increasing percentage of LDPE reduced the tensile strength and Young’s modulus of the PLA/LDPE samples due to the lower intermolecular bonding of LDPE than of PLA. Moreover, an increase in irradiation dosages gradually decreased the mechanical properties of low-LDPE PLA/LDPE. In contrast, the increasing irradiation dosage enhanced the mechanical properties of higher-LDPE PLA/LDPE. These results indicate that higher amounts of LDPE effectively react with the release of free radicals within the amorphous phase if the blends are subjected to irradiation. The higher amounts of free radicals induce the formation of three-dimensional cross-linked networks in the polymer matrix and thus increase the gel content. The irradiation-induced cross-linking in PLA/LDPE samples improves the mechanical properties and crystallinity by promoting a structural rearrangement of the polymer matrix into a highly ordered structure.

  20. Effects of electron beam irradiation on the structural properties of polylactic acid/polyethylene blends

    International Nuclear Information System (INIS)

    Bee, Soo-Tueen; Ratnam, C.T.; Sin, Lee Tin; Tee, Tiam-Ting; Wong, Wai-Kien; Lee, Jiuun-Xiang; Rahmat, A.R.

    2014-01-01

    Highlights: •Electron beam irradiation on polyethylene (LDPE) and polylactic acid (PLA) blends. •Irradiated PLA/LDPE blends exhibit structural rearrangement to highly ordered structure. •Irradiated PLA/LDPE matrix extends continuity of polymer matrix with larger fibrils diameter. -- Abstract: The purpose of this research was to investigate the effects of electron beam irradiation on the properties of polylactic acid (PLA) and low density polyethylene (LDPE) blends. The PLA were compounded with 20–80% LDPE and were exposed to electron beam irradiation dosages of 20–120 kGy. The results from gel content and X-ray diffraction analyses showed that the addition of LDPE to PLA effectively increased the gel content and crystallinity. However, an increasing percentage of LDPE reduced the tensile strength and Young’s modulus of the PLA/LDPE samples due to the lower intermolecular bonding of LDPE than of PLA. Moreover, an increase in irradiation dosages gradually decreased the mechanical properties of low-LDPE PLA/LDPE. In contrast, the increasing irradiation dosage enhanced the mechanical properties of higher-LDPE PLA/LDPE. These results indicate that higher amounts of LDPE effectively react with the release of free radicals within the amorphous phase if the blends are subjected to irradiation. The higher amounts of free radicals induce the formation of three-dimensional cross-linked networks in the polymer matrix and thus increase the gel content. The irradiation-induced cross-linking in PLA/LDPE samples improves the mechanical properties and crystallinity by promoting a structural rearrangement of the polymer matrix into a highly ordered structure

  1. Pollen flora of pakistan-lxxi. rosaceae

    International Nuclear Information System (INIS)

    Perveen, A.; Qaiser, M.

    2014-01-01

    Pollen morphology of 50 species representing 17 genera of the family Rosaceae i.e., Alchemilla, Argimonia, Cotoneaster, Crataegus, Duchesnea, Fragaria, Eriybotyra, Filipandula, Geum, Malus, Prunus, Potentilla, Pyrus , Rosa, Sibbaldia, Sorbaria and Sorbus has been studied from Pakistan by light and scanning electron microscope. Pollen grains are usually free, radially symmetrical, isopolar, prolate-spheroidal to subprolate or oblate-spheroidal rarely perprolate, tricolporate rarely tricolpate. Tectum mostly coarsely-finely striate, rarely striate-rugulate, scabrate or spinulose often reticulate. Rosaceae is more or less eurypalynous family. Significant variation is found in P/E ratio, shape and exine ornamentation and on the basis of these characters family has been divided into seven pollen types viz., Agrimonia eupatoria-type, Alchemilla ypsilotoma-type, Cotoneaster affinis-type, Fragaria nubicola-type, Geum roylei-type, Malus pumila-type, Potentilla pamirica-type. Pollen data is useful at specific and generic level. (author)

  2. 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.

  3. 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

  4. Magnetic quadrupole resonance of electron irradiated aluminium. Electric field gradients surrounding the vacancies and interstitials

    International Nuclear Information System (INIS)

    Andreani, R.; Minier, M.; Minier, C.

    Some aluminium samples were irradiated at 20K with 3MeV electrons. The quadrupole absorption spectra have been obtained after irradiation and annealing, at 50K, 150K and 300K. Coupled conductivity measurements allowed the evolution in defect concentration to be studied. This new method makes it possible to characterize the presence of vacancies independently of the simultaneous existence of bivacancies, interstitials and clusters [fr

  5. Dose response of thin-film dosimeters irradiated with 80-120 keV electrons

    DEFF Research Database (Denmark)

    Helt-Hansen, J.; Miller, A.; Sharpe, P.

    2005-01-01

    Thin-film dosimeters (Riso B3 and alanine films) were irradiated at 10 MeV and 80-120 keV electron accelerators, and it has been shown that the radiation response of the dosimeter materials (the radiation chemical yields) are constant at these irradiation energies. However, dose gradients within ...... are present within the dosimeter. (C) 2005 Elsevier Ltd. All rights reserved....

  6. Structure and properties of binary polystyrene-epoxy acrylate oligomer mixtures irradiated by electron beams

    International Nuclear Information System (INIS)

    Lomonosova, N.V.

    1995-01-01

    The change in the structure of oriented polymer-oligomer systems based on polystyrene (PS) with M > 10 6 and epoxy acrylate oligomers (aliphatic and aromatic) under irradiation by accelerated electrons was studied using birefringence, isometric heating, IR dichroism, and thermooptical analysis. Mechanical properties of these systems were investigated. It was found that, by adding aliphatic epoxy acrylate to PS and further irradiating this mixture, one can obtain both isotropic and oriented composites with higher strengths, elasticity moduli, and glass transition temperatures

  7. Vacancy defects in electron-irradiated ZnO studied by Doppler broadening of annihilation radiation

    Science.gov (United States)

    Chen, Z. Q.; Betsuyaku, K.; Kawasuso, A.

    2008-03-01

    Vacancy defects in ZnO induced by electron irradiation were characterized by the Doppler broadening of annihilation radiation measurements together with the local density approximation calculations. Zinc vacancies (VZn) are responsible for positron trapping in the as-irradiated state. These are annealed out below 200°C . The further annealing at 400°C results in the formation of secondary defects attributed to the complexes composed of zinc vacancies and zinc antisites (VZn-ZnO) .

  8. Low-temperature annealing of radiation defects in electron-irradiated gallium phosphide

    International Nuclear Information System (INIS)

    Kolb, A.A.; Megela, I.G.; Buturlakin, A.P.; Goyer, D.B.

    1990-01-01

    The isochronal annealing of radiation defects in high-energy electron irradiated n-GaP monocrystals within the 77 to 300 K range has been investigated by optical and electrical techniques. The changes in conductance and charge carrier mobility as functions of annealing temperature as well as the variation of optical absorption spectra of GaP under irradiation and annealing provide evidence that most of radiation defects are likely secondary complexes of defects

  9. Influence of electron beam irradiation on growth of Phytophthora cinnamomi and its control in substrates

    International Nuclear Information System (INIS)

    MigdaŁ, Wojciech; Orlikowski, Leszek B.; Ptaszek, Magdalena; Gryczka, Urszula

    2012-01-01

    Very extensive production procedure, especially in plants growing under covering, require methods, which would allow quick elimination or substantial reduction of populations of specific pathogens without affecting the growth and development of the cultivated plants. Among soil-borne pathogens, the Phytophthora species are especially dangerous for horticultural plants. In this study, irradiation with electron beam was applied to control Phytophthora cinnamomi. The influence of irradiation dose on the reduction of in vitro growth and the population density of the pathogen in treated peat and its mixture with composted pine bark (1:1), as well as the health of Chamaecyparis lawsoniana and Lavandula angustifolia plants were evaluated. Application of irradiation at a dose of 1.5 kGy completely inhibited the in vitro development of P. cinnamomi. This irradiation effect was connected with the disintegration of the hyphae and spores of the species. Irradiation of peat and its mixture with composted pine bark with 10 kGy resulted in the inhibition of stem base rot development in Ch. lawsoniana. Symptoms of the disease were not observed when the substrates were treated with 15 kGy. In the case of L. angustifolia, stem root rot was not observed on cuttings transplanted to infected peat irradiated at a dose of 10 kGy. Irradiation of the horticultural substrates did not affect plant growth. - Highlights: ► Electron beam irradiation is effective against soil-borne pathogens. ► Application of irradiation at dose 1.5 kGy completely inhibited in vitro development of Phytophthora cinnamomi. ► Irradiation of horticultural substrata did not influence the growth of plants.

  10. Positron annihilation and thermally stimulated current of electron beam irradiated polyetheretherketone

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Shigetaka; Shinyama, Katsuyoshi; Baba, Makoto [Hachinohe Inst. of Tech., Hachinohe, Aomori (Japan); Suzuki, Takenori

    1997-03-01

    Positron lifetime measurements were applied to electron beam irradiated poly(ether-ether-ketone). The lifetime, {tau}{sub 3}, of the ortho-positronium of unirradiated and 5 MGy irradiated specimen became rapidly longer above about 150degC. {tau}{sub 3} of 50 MGy and 100 MGy irradiated specimen was shorter than that of unirradiated one. Thermally stimulated current (TSC) decreased with increasing the dose before voltage application. In the case of voltage application, a TSC peak appeared and the peak value decreased with increased the dose. The correlation between the results of positron annihilation and TSC was investigated. (author)

  11. Effect of electron beam irradiation on viscosity/temperature characteristics of cellulose derivatives

    International Nuclear Information System (INIS)

    Mastro, N.L. del; Villavicencio, A.L.C.; Yamasaki, M.C.R.

    1991-11-01

    The direct relationship between intrinsic viscosity and molecular weight of polymers allowed to attend the aggregation, cross-linking and degradation processes induced by electron beam irradiation on carboxymethylcellulose and hydroxiethylcellulose in aqueous solutions. The changes in viscosity were related to irradiation doses from 2.5x10 4 Gy to 25x10 4 Gy at 5 0 C, 25 0 C, 50 0 C and 75 0 C measured at different intervals after irradiation. The results showed the viscosity decrease characteristics as a function of those parameters for each one of the polymers. (author)

  12. Detection by electron spin resonance of young cock irradiated with 60 Co

    International Nuclear Information System (INIS)

    Villavicencio, A.L.C.H.; Duarte, C.L.; Mastro, N.L. del.

    1992-01-01

    The Electron Spin Resonance was used to measuring the production of free radicals induced by ionizing radiation in young cock bones on doses of 3,5 and 7,0 K Gy. It was studied the design decay by 30 days after the irradiation in environment temperature. The results show that the measures by resonance in bones can be used for detecting if the flesh sample that has bone was irradiated or not. The measures show the possibility of use post-irradiation dosimetry in food producst. (C.G.C.)

  13. Radioprotective efficacy of Carica papaya (L.) leaf extract in electron beam irradiated Swiss albino mice

    International Nuclear Information System (INIS)

    Yogish Somayaji, T.; Suchetha Kumari, N.

    2016-01-01

    Previous studies have shown that leaf extract of Carica papaya (Linn.) has antibacterial, antitumor, antioxidant, anti-sickling properties and has shown to increase the platelets in patients with dengue fever. In the present study, the radioprotective effects and radioadaptive response of Carica papaya (L.) was evaluated in mice irradiated with electron beam radiation. Radiation induced hematological suppression was seen at sublethal doses of 6 Gy irradiated groups. There was a decrease in hemoglobin, red blood cell, total white blood cell count and platelet counts in irradiated groups whereas papaya leaf extract enhanced platelet levels indicated thrombopoietic effect

  14. Effect of electron irradiation on defect distribution in solar cells for space applications

    International Nuclear Information System (INIS)

    Charles, J.P.; Bruguier, G.; Mialhe, P.; Ruas, R.

    1989-01-01

    The distribution of the recombination centers in the spacecharge region was highly dissymetrical before irradiation. After irradiation by a high density electron beam of 10 15 cm -2 with an energy of 1 MeV, the recombination process predominates in the whole bias range. The irradiation yields both an increase in density of the recombination centers and a more homogeneous distribution of traps in the space charge region with an improvement in the behaviour of cells (via the fill factor). This effect is counterbalanced by poor operation in the base and the emitter with a decrease in the efficiency of the device by 20% [fr

  15. Vascular damage after acute local irradiation: a light and electron microscope study

    International Nuclear Information System (INIS)

    Verola, O.; Brocheriou, C.

    1986-01-01

    A pig model was used to examine histological and ultrastructural changes after high-dose local irradiation. This model was chosen to simulate accidents which have occurred in man, enabling the determination of several post-irradiation phases. After an initial phase, with superficial lesions, ischaemic necrosis occurred 3 weeks after irradiation as the result of early vascular alterations. After 2 months, expanding necrosis became obvious in the deep muscle, preceded by an initial spread of vascular lesions: these alterations were obvious from the 30th day by light microscopy but could be detected by electron microscopy from the 9th day. (author)

  16. Various categories of defects after surface alloying induced by high current pulsed electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Dian [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Tang, Guangze, E-mail: oaktang@hit.edu.cn [School of Material Science & Engineering, Harbin Institute of Technology, Harbin 150001 (China); Ma, Xinxin [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Gu, Le [School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001 (China); Sun, Mingren [School of Material Science & Engineering, Harbin Institute of Technology, Harbin 150001 (China); Wang, Liqin [School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2015-10-01

    Highlights: • Four kinds of defects are found during surface alloying by high current electron beam. • Exploring the mechanism how these defects appear after irradiation. • Increasing pulsing cycles will help to get good surface quality. • Choosing proper energy density will increase surface quality. - Abstract: High current pulsed electron beam (HCPEB) is an attractive advanced materials processing method which could highly increase the mechanical properties and corrosion resistance. However, how to eliminate different kinds of defects during irradiation by HCPEB especially in condition of adding new elements is a challenging task. In the present research, the titanium and TaNb-TiW composite films was deposited on the carburizing steel (SAE9310 steel) by DC magnetron sputtering before irradiation. The process of surface alloying was induced by HCPEB with pulse duration of 2.5 μs and energy density ranging from 3 to 9 J/cm{sup 2}. Investigation of the microstructure indicated that there were several forms of defects after irradiation, such as surface unwetting, surface eruption, micro-cracks and layering. How the defects formed was explained by the results of electron microscopy and energy dispersive spectroscopy. The results also revealed that proper energy density (∼6 J/cm{sup 2}) and multi-number of irradiation (≥50 times) contributed to high quality of alloyed layers after irradiation.

  17. Electronic excitation induced modifications in elongated iron nanoparticle encapsulated multiwalled carbon nanotubes under ion irradiation

    Science.gov (United States)

    Saikiran, V.; Bazylewski, P.; Sameera, I.; Bhatia, Ravi; Pathak, A. P.; Prasad, V.; Chang, G. S.

    2018-05-01

    Multi-wall carbon nanotubes (MWCNT) filled with Fe nanorods were shown to have contracted and deformed under heavy ion irradiation. In this study, 120 MeV Ag and 80 MeV Ni ion irradiation was performed to study the deformation and defects induced in iron filled MWCNT under heavy ion irradiation. The structural modifications induced due to electronic excitation by ion irradiation were investigated employing high-resolution transmission electron microscopy, micro-Raman scattering experiments, and synchrotron-based X-ray absorption and emission spectroscopy. We understand that the ion irradiation causes modifications in the Fe nanorods which result in compressions and expansions of the nanotubes, and in turn leads to the buckling of MWCNT. The G band of the Raman spectra shifts slightly towards higher wavenumber and the shoulder G‧ band enhances with the increase of ion irradiation fluence, where the buckling wavelength depends on the radius 'r' of the nanotubes as exp[(r)0.5]. The intensity ratio of the D to G Raman modes initially decreases at the lowest fluence, and then it increases with the increase in ion fluence. The electron diffraction pattern and the high resolution images clearly show the presence of ion induced defects on the walls of the tube and encapsulated iron nanorods.

  18. The structural design of an electron gun for an E-beam irradiator

    International Nuclear Information System (INIS)

    Yu Xiaojuan; Wu Xunlei; Jiang Zhenbo; Meng Mingfeng

    2011-01-01

    In this paper, an electron gun for a linac E-beam irradiator is developed with a replaceable cathode and filament. The structure of cathode and filament and the concentric technique, with molds and clamps, are described in detail. The electron gun was assembled with care to reduce the error, and ensure the concentricity of electron gun. The test results indicated a 99.99% pass ratio of the electron beams at 60-65 kV. The electron gun design meets the technical requirement of clients. (authors)

  19. Influence of electron irradiation on hydrothermally grown zinc oxide single crystals

    International Nuclear Information System (INIS)

    Lu, L W; So, C K; Zhu, C Y; Gu, Q L; Fung, S; Ling, C C; Li, C J; Brauer, G; Anwand, W; Skorupa, W

    2008-01-01

    The resistivity of hydrothermally grown ZnO single crystals increased from ∼10 3 Ω cm to ∼10 6 Ω cm after 1.8 MeV electron irradiation with a fluence of ∼10 16 cm −2 , and to ∼10 9 Ω cm as the fluence increased to ∼10 18 cm −2 . Defects in samples were studied by thermally stimulated current (TSC) spectroscopy and positron lifetime spectroscopy (PLS). After the electron irradiation with a fluence of 10 18 cm −2 , the normalized TSC signal increased by a factor of ∼100. A Zn vacancy was also introduced by the electron irradiation, though with a concentration lower than expected. After annealing in air at 400 °C, the resistivity and the deep traps concentrations recovered to the levels of the as-grown sample, and the Zn vacancy was removed

  20. Metallic Na formation in NaCl crystals with irradiation of electron or vacuum ultraviolet photon

    Energy Technology Data Exchange (ETDEWEB)

    Owaki, Shigehiro [Osaka Prefecture Univ., Sakai, Osaka (Japan). Coll. of Integrated Arts and Sciences; Koyama, Shigeko; Takahashi, Masao; Kamada, Masao; Suzuki, Ryouichi

    1997-03-01

    Metallic Na was formed in NaCl single crystals with irradiation of a variety of radiation sources and analyzed the physical states with several methods. In the case of irradiation of 21 MeV electron pulses to the crystal blocks, the optical absorption and lifetime measurement of positron annihilation indicated appearance of Na clusters inside. Radiation effects of electron beam of 30 keV to the crystals in vacuum showed the appearance of not only metallic Na but atomic one during irradiation with Auger electron spectroscopy. Intense photon fluxes in vacuum ultraviolet region of synchrotron radiation were used as another source and an analyzing method of ultraviolet photoelectron spectroscopy. The results showed the metallic Na layered so thick that bulk plasmon can exist. (author)