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Sample records for beam irradiation effects

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

    Indian Academy of Sciences (India)

    Zheng Jiao; Xiaojuan Wan; Bing Zhao; Huijiao Guo; Tiebing Liu; Minghong Wu

    2008-02-01

    In this paper, the effects of electron beam irradiation on the gas sensing performance of tin dioxide thin films toward H2 are studied. The tin dioxide thin films were prepared by ultrasonic spray pyrolysis. The results show that the sensitivity increased after electron beam irradiation. The electron beam irradiation effects on tin dioxide thin films were simulated and the mechanism was discussed.

  2. Effects of ion beam irradiation on semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Nashiyama, Isamu; Hirao, Toshio; Itoh, Hisayoshi; Ohshima, Takeshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    Energetic heavy-ion irradiation apparatus has been developed for single-event effects (SEE) testing. We have applied three irradiation methods such as a scattered-ion irradiation method, a recoiled-atom irradiation method, and a direct-beam irradiation method to perform SEE testing efficiently. (author)

  3. Biological effect of penetration controlled irradiation with ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi; Shimizu, Takashi; Kikuchi, Masahiro; Kobayashi, Yasuhiko; Watanabe, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Yamashita, Takao

    1997-03-01

    To investigate the effect of local irradiation with ion beams on biological systems, technique for penetration controlled irradiation has been established. The range in a target was controlled by changing the distance from beam window in the atmosphere, and could be controlled linearly up to about 31 {mu}m in biological material. In addition, the effects of the penetration controlled irradiations with 1.5 MeV/u C and He ions were examined using tobacco pollen. The increased frequency of leaky pollen produced by ion beams suggests that the efficient pollen envelope damages would be induced at the range-end of ion beams. (author)

  4. Effects of Electron Beam Irradiation on the Electrospinning of Polyacrylonitrile.

    Science.gov (United States)

    Jeun, Joon-Pyo; Kim, Hyun-Bin; Oh, Seung-Hwan; Park, Jung-Ki; Kang, Phil-Hyun

    2015-08-01

    Electron beam (e-beam) irradiation of polyacrylonitrile (PAN) was performed to investigate the effects of radiation on the electrospinning process. For this study, polyacrylonitrile powder was subjected to e-beam irradiation with different doses of up to 100 kGy under an N2 atmosphere. Polymer solutions were prepared by dissolving PAN in N,N-dimethyl-formamide (DMF) at a 1:9 ratio by weight. The prepared PAN/DMF solutions showed different colors with different e-beam doses. The resulting structures in solutions contained conjugated C=N bonds, which caused the observed color formation. In addition, the conductivity of the PAN/DMF solution increased with an increase in e-beam irradiation dose. In the DSC spectra of electrospun PAN fibers, the peak temperature of the exothermic reactions was observed to decrease with an increase in the e-beam irradiation strength. PMID:26369176

  5. Effect of electron beam irradiation on seed germination

    International Nuclear Information System (INIS)

    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

  6. 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.

  7. Effect of electron beam irradiation on surgical rubber gloves

    International Nuclear Information System (INIS)

    This paper outlines the effects of electron beam irradiation on surgical rubber gloves. The tensile strength, elongation at break and modulus were evaluated as function of dose range 20-100 kGy minimum dose, dose uniformity ratio, 3.1, and both, accelerated and normal aging, were used to study the stability of the irradiated gloves after irradiation. The surgical gloves were found to be useful up to the highest dose tested. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Dohino, Toshiyuki; Tanabe, Kazuo [Yokohama Plant Protection Station (Japan)

    1994-08-01

    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).

  9. Electron beam irradiation effects on aromatic polymers

    International Nuclear Information System (INIS)

    Electron irradiation effects on aromatic polymers having various molecular structures were studied to elucidate the following subjects; (1) relation between radiation stability and molecular structure of repeating units, (2) mechanism of deterioration and (3) adaptability to matrix resin for radiation resistant FRP. Results are summarized as follows: (1) An order of radiation stability of units is; imide ring > diphenyl ether, diphenyl ketone > aromatic amide >> bis-phenol A > diphenyl sulphone. (2) Poly (ether-ether-ketone) and most polyimide are crosslinkable but polysulphones and polyarylate are chain degradation type polymers. (3) Newly developed thermoplastic polyimides have possibilities for use as matrix materials in radiation resistant FRP. (author)

  10. Electron beam irradiation effects on some packaged dried food items

    International Nuclear Information System (INIS)

    For radical sports practitioners, small nutritious snack foods are needed. At the same time, food preparation must guarantee long shelf life and be compact or lightweight for easiness of carrying. Commercial individually packaged foods can be used either for sports practitioners like adventure racing or eventually as military rations. Irradiation processing of foods is an important preservation technology. High-voltage electron beams generated from linear accelerators are an alternative to radioisotope generators as they require much shorter exposure times (seconds vs. hours for γ irradiation) to be effective and are currently used to pasteurize meat products among others food items. This work describes the application of electron beam irradiation on some food items used in sport training diets: fiber rich cookies, fruit cereal bars, instant dehydrated asparagus soup and instant Brazilian corn pudding. Each kind of sample contained 3 groups of 15 units each. Irradiation was performed with an electron beam accelerator Dynamitron (Radiation Dynamics Inc.) model JOB 188, with doses of 5 and 10 kGy. For the evaluation of irradiated samples a methodology based on the Analytical Norms of the Instituto Adolfo Lutz, one of the South America Reference Laboratories was employed. The microbiological and sensory analyses of the diverse irradiated samples are presented. Electron beam irradiation resulted in significant reduction of the fungus and yeast load but caused dose dependent differences of some sensory characteristics. A careful dose choice and special irradiation conditions must be used in order to achieve sensory requirements needed for the commercialization of these irradiated food items. (author)

  11. Synergistic effects obtained by combined electron beam and microwave irradiation

    International Nuclear Information System (INIS)

    A new method based on microwave energy addition to accelerated electron beam energy for material processing was developed. The main idea of this work was to combine the advantages of both electron beam (EB) irradiation and microwave (MW) irradiation, i.e. EB high irradiation efficiency and MW high selectivity and volumetric heating, for material processing. The first expected and obtained result was the decrease of the required EB absorbed dose. Thus, the ionizing radiation costs could be reduced and the application of low intensity EB accelerators will become very economically attractive in the material-processing field. Another expected and obtained result was the improvement of material properties. A special designed facility consisting of an EB accelerator of 5.5 MeV and a MW source of 2.45 GHz and 1.6 kW that performs combined EB and MW irradiation is presented. There are three fields of interest under our investigation for application of combined EB and MW irradiation: environmental waste treatment (sewage sludge, flue gases), sterilization (food residuals, hospital wastes) and food quality and safety. Both, EB (ionizing radiation) and MW (non-ionizing) material processing are based on the radiation ability to alter physical and chemical properties of materials. Irradiation with electron beams was put forth as a very effective method for material processing because can produce ions, electrons, and free radicals at any temperature in the solid, liquid and gas. EB processes are very effective for material processing but the required absorbed dose is still high for pollutants removal, sterilization, vulcanization, etc. MW processing of materials is a relatively new technology that provides new approaches to improve the physical properties of materials and to produce new materials and microstructures that cannot be achieved by other methods. MW processes are less effective for material processing than EB processes but the cost of microwave systems is considerably

  12. Effects on focused ion beam irradiation on MOS transistors

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, A.N.; Peterson, K.A.; Fleetwood, D.M.; Soden, J.M.

    1997-04-01

    The effects of irradiation from a focused ion beam (FIB) system on MOS transistors are reported systematically for the first time. Three MOS transistor technologies, with 0.5, 1, and 3 {mu}m minimum feature sizes and with gate oxide thicknesses ranging from 11 to 50 nm, were analyzed. Significant shifts in transistor parameters (such as threshold voltage, transconductance, and mobility) were observed following irradiation with a 30 keV Ga{sup +} focused ion beam with ion doses varying by over 5 orders of magnitude. The apparent damage mechanism (which involved the creation of interface traps, oxide trapped charge, or both) and extent of damage were different for each of the three technologies investigated.

  13. Electron beam irradiation effect on GaN HEMT

    International Nuclear Information System (INIS)

    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)

  14. Effects of electron beam irradiation on bovine pericardium tissue

    Energy Technology Data Exchange (ETDEWEB)

    Polak, Roberta; Pitombo, Ronaldo N.M. [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Tecnologia Bioquimico-Farmaceutica], e-mail: robertaplk@gmail.com, e-mail: pitombo@usp.br; Rodas, Andrea C.D.; Higa, Olga Z. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Centro de Biotecnologia], e-mail: andrea.ipen@gmail.com, e-mail: ozhiga@ipen.br; Kodama, Yasko; Machado, Luci D.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes], e-mail: ykodama@ipen.br

    2009-07-01

    In this work, electron beam irradiation was studied as a way for bovine pericardium (BP) tissue crosslinking. BP samples were irradiated in an electron beam accelerator at different doses (12.5 and 25 kGy), at three different dose ratios (4.67, 9.34 kGy/s), in the presence and absence of oxygen. Irradiated samples were analyzed by Differential Scanning Calorimetry (DSC), Thermogravimetry (TGA), Scanning Electron Microscopy (SEM) and swelling degree. DSC analysis showed a decrease in shrinkage temperature. However, for all irradiated samples, the energy required in the process was higher than the non irradiated BP. The TGA analysis showed that the thermal behavior, both the control and the irradiated samples, was characterized by three stages concerned in the loss of mass. The BP structure was characterized by swelling degree and SEM. The structure of the BP tissue suffered alteration, becoming looser, or more compact. By swelling degree, when the BP was irradiated in the presence of oxygen, the swelling degree value was higher than non irradiated BP, in the other hand the swelling degree value of BP irradiated in oxygen absence were lower than the non irradiated BP. Those results indicate that the BP irradiated in absence of oxygen could predominantly crosslinks. The BP degradation when it was irradiated in presence of oxygen was confirmed by SEM. (author)

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

    International Nuclear Information System (INIS)

    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

  16. LET effects of high energy ion beam irradiation on polysilanes

    Energy Technology Data Exchange (ETDEWEB)

    Seki, Shu; Kanzaki, Kenichi; Tagawa, Seiichi; Yoshida, Yoichi [Osaka Univ., Ibaraki (Japan). Inst. of Scientific and Industrial Research; Kudoh, Hisaaki; Sugimoto, Masaki; Sasuga, Tsuneo; Seguchi, Tadao; Shibata, Hiromi

    1997-03-01

    Thin films of poly(di-n-hexylsilane) were irradiated with 2-20 MeV H{sup +} and He{sup +} ion beams. The beams caused heterogeneous reactions of crosslinking and main chain scission in the films. The relative efficiency of the crosslinking was drastically changed in comparison with that of main chain scission. The anomalous change in the molecular weight distribution was analyzed with increasing irradiation fluence, and the ion beam induced reaction radius; track radius was determined for the radiation sources by the function of molecular weight dispersion. Obtained values were 59{+-}15 A and 14{+-}6 A for 2 MeV He{sup +} and 20 MeV H{sup +} ion beams respectively. (author)

  17. Electron beam irradiation effects on xanthan gum, rheological aspects

    International Nuclear Information System (INIS)

    Food ingredients to be used for food processing should be decontaminated in order to prevent food spoilage and food-borne diseases. Xanthan gum is a well-known microbial polysaccharide produced by Xanthomonas campestris used in the hydrocolloid market. This paper describes the application of electron beam (EB) irradiation to xanthan gum as used as ingredient by the food or cosmetics industry in order to establish their radiosensitivity. Viscosity of 1% xanthan gum solutions prepared with the irradiated powder decreased with the increase of the EB irradiation dose. The radiation-induced viscosity detriment of this additive must be considered for practical applications. (author)

  18. Effect of electron-beam irradiation on graphene field effect devices

    OpenAIRE

    Childres, I.; Jauregui, L A; Foxe, M.; Tian, J. F.; R. Jalilian; Jovanovic, I; Chen, Y P

    2010-01-01

    Electron beam exposure is a commonly used tool for fabricating and imaging graphene-based devices. Here, we present a study of the effects of electron-beam irradiation on the electronic transport properties of graphene and the operation of graphene field-effect transistors (GFETs). Exposure to a 30 keV electron-beam caused negative shifts in the charge-neutral point (CNP) of the GFET, interpreted as due to n-dopin...

  19. Effect of Electron Beam Irradiation on the Tensile Properties of Carbon Nanotubes Sheets and Yarns

    Science.gov (United States)

    Williams, Tiffany S.; Miller, Sandi G.; Baker, James S.; McCorkle, Linda S.; Meador, Michael A.

    2013-01-01

    Carbon nanotube sheets and yarns were irradiated using electron beam (e-beam) energy to determine the effect of irradiation dose on the tensile properties. Results showed that a slight change in tensile strength occurred after irradiating as-received CNT sheets for 20 minutes, and a slight decrease in tensile strength as the irradiation time approached 90 minutes. On the other hand, the addition of small molecules to the CNT sheet surface had a greater effect on the tensile properties of e-beam irradiated CNT sheets. Some functionalized CNT sheets displayed up to a 57% increase in tensile strength following 90 minutes of e-beam exposure. In addition, as-received CNT yarns showed a significant increase in tensile strength as the irradiation time increased.

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

    International Nuclear Information System (INIS)

    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)

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

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyunwook; Kim, Hackyoun; Hwang, Koeun; Choi, Sunmi; Kim, Cheonjei; Choi, Jihun; Choi, Yunsang [Konkuk Univ., Seoul (Korea, Republic of); Lee, Juwoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-07-01

    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.

  2. The effects of electron beam irradiation on sterilization and preservation of chilled pork

    International Nuclear Information System (INIS)

    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(X1) and dose(X2) 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=3.78-0.24X1-0.13X2-0.16X1X2-0.18X12+0.15X12(R2=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)

  3. Effect of electron beam irradiation on the quality of fish meal

    International Nuclear Information System (INIS)

    Samples of soybean meal were exposed to electron beam with dosage levels of 0, .083, 1.56, 2.30, 4.93, 7.84 kGy, to evaluate the efficacy of electron beam for decontamination as well as the effect of electron beam irradiation on feeding quality of fish meal. The results showed that the total numbers of aerobic bacteria were reduced to 600 CFU/g and fungi inhibited to 0.05). Volatile basic nitrogen enhanced by electron beam irradiation (p0.05). Total acidity value unchanged by irradiation, but peroxide value was decreased as the dosage increased (p<0.05). It was concluded that the irradiation dosage of 1.56 ∼ 7.84 kGy was very effective for microbial decontamination of fish meal, and did not adversely affect the nutritional quality of fish meal. (authors)

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

    International Nuclear Information System (INIS)

    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

  5. The Irradiation Effect of a Simultaneous Laser and Electron Dual-beam on Void Formation

    OpenAIRE

    Zhanbing Yang; Seiichi Watanabe; Takahiko Kato

    2013-01-01

    Randomly distributed lattice point defects such as supersaturated vacancies (SVs) and Frenkel-pairs (FPs, an interstitial and a vacancy) can be simultaneously introduced into the crystal by energetic beam irradiation in outer space and/or nuclear reactors, but their behavior has not been fully understood. Using a high-voltage electron microscope equipped with a laser (laser-HVEM), we show the striking effects of simultaneous laser-electron (photon-electron) dual-beam irradiation on void forma...

  6. Effect of electron beam irradiation sterilization on the biomedical poly (octene-co-ethylene)/polypropylene films

    Energy Technology Data Exchange (ETDEWEB)

    Luan Shifang [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Shi Hengchong [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Graduate University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100039 (China); Yao Zhanhai [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Wang Jianwei [Shandong Weigao Group Medical Polymer Co., Ltd., Weihai 264209 (China); Song Yongxian [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Yin Jinghua, E-mail: yinjh@ciac.jl.c [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2010-05-01

    The effect of electron beam irradiation with the dose ranging from 15 to 40 kGy on poly (octene-co-ethylene) (POE)/polypropylene (PP) films was investigated. Wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), yellowness index testing and mechanical performance measurement were applied to characterize the films. It demonstrated that crystalline structure exhibited little change, and degree of crystallinity slightly change under the irradiation treatment. Irradiation brought about oxidation of the films, forming hydroxyl groups of the peroxides and carbonyl groups. Tensile properties become worse as irradiation dose increased. Electron beam irradiation with the dose of 15-40 kGy has little effect on crystalline performance and a little influence for the POE/PP films, indicating a good irradiation resistance.

  7. Effect of Gamma and Electron Beam Irradiation on Textile Waste Water

    International Nuclear Information System (INIS)

    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)

  8. Effect of electron beam irradiation on the nutritional ingredient of Sciaenops ocellatus meat

    International Nuclear Information System (INIS)

    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)

  9. Effects of Ga ion-beam irradiation on monolayer graphene

    International Nuclear Information System (INIS)

    The effects of Ga ion on the single layer graphene (SLG) have been studied by Raman spectroscopy (RS), SEM, and field-effect characterization. Under vacuum conditions, Ga ion-irradiation can induce disorders and cause red shift of 2D band of RS, rather than lattice damage in high quality SLG. The compressive strain induced by Ga ion decreases the crystalline size in SLG, which is responsible for the variation of Raman scattering and electrical properties. Nonlinear out-put characteristic and resistance increased are also found in the I-V measurement. The results have important implications during CVD graphene characterization and related device fabrication

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

    International Nuclear Information System (INIS)

    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)

  11. Effect of irradiation of electron beam on protein and antioxidized enzyme activity of microcystis aeruginosa

    International Nuclear Information System (INIS)

    Microcystis aeruginosa often threatens human health and safety for its microcystin and bad smell. Its large number and hardness of removal are difficulty for water treatment. In this study, electron beam generated by an accelerator was applied to irradiate Microcystis aeruginosa by dose of l, 2, 3, 4 and 5 kGy. The effect of irradiation on Microcystis aeruginosa characteristic and mechanism was studied by surveying the changing of protein, enzyme activity and photosynthesis rate. The data show that irradiation of 1 kGy has little effect on dissoluble protein, POD and SOD activity. Irradiation of 25 kGy can decrease protein content and destroy the antioxidant system, also the photosynthesis rate decreases obviously, which makes Microcystis aeruginosa lose activity in short time. The result proves that a certain dose of electron beam irradiation can control algae growth and affect its life characteristic efficiently. (authors)

  12. Comparison of the effects of gamma ray and e-beam irradiation on the quality of minced beef during storage

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Nam; Han, In Jun; Kim, Wang Geun; Song, Beom Seok; Kim, Jae Hun; Choi, Jong Il; Yoon, Yo Han; Byun, Myung Woo; Hwang, Han Joon; Lee, Ju Woon [Korea Atomic Energy Research Institte, Jeongeup (Korea, Republic of); Park, Jin Gyu [Korea University, Seoul (Korea, Republic of)

    2009-06-15

    This study was conducted to compare the microbiological and physicochemical qualities of minced beef irradiated with gamma ray of e-beam at the absorbed doses from 5 to 20 kGy. The total bacterial counts of minced beef were decreased depending upon the irradiation doses, but sterilizing effect of gamma irradiation was higher than that of e-beam irradiation. The contents of malondialdegyde of minced beef were increased depending upon irradiation doses as well as storage periods (p< 0.05). Volatile basic nitrogen in minced beef was constantly increased during storage, but the increasing rate were retarded by irradiation. The hunter's color values(L*, a* and b*) of gamma or e-beam irradiated minced beef were decreased as irradiation dose increasing. Meanwhile, the quality changes of gamma irradiated samples were faster than e-beam irradiated samples.

  13. Comparison of the effects of gamma ray and e-beam irradiation on the quality of minced beef during storage

    International Nuclear Information System (INIS)

    This study was conducted to compare the microbiological and physicochemical qualities of minced beef irradiated with gamma ray of e-beam at the absorbed doses from 5 to 20 kGy. The total bacterial counts of minced beef were decreased depending upon the irradiation doses, but sterilizing effect of gamma irradiation was higher than that of e-beam irradiation. The contents of malondialdegyde of minced beef were increased depending upon irradiation doses as well as storage periods (p< 0.05). Volatile basic nitrogen in minced beef was constantly increased during storage, but the increasing rate were retarded by irradiation. The hunter's color values(L*, a* and b*) of gamma or e-beam irradiated minced beef were decreased as irradiation dose increasing. Meanwhile, the quality changes of gamma irradiated samples were faster than e-beam irradiated samples

  14. Effects of gamma and electron beam irradiation on the properties of calendered cord fabrics

    International Nuclear Information System (INIS)

    The effects of gamma and e-beam irradiation on mechanical and structural properties of nylon 66 (Ny 66), nylon 6 (Ny 6) and poly(ethylene terephthalate) (PET) fabrics used in tyres were investigated. The untreated (greige), treated cords and calendered fabrics were irradiated at different doses. It is found that the effects of high energy irradiation on greige, treated cords and calendered fabrics are similar. No protective effect of compounds used in calendering was observed against radiation-induced oxidative degradation. The deterioration effect of gamma irradiation on mechanical properties is much higher than that of e-beam irradiation for all types of samples. Limiting viscosity numbers of both gamma and e-beam irradiated nylon 6 and nylon 66 cords were found to decrease with increasing dose. It is concluded that PET calendered fabric has higher resistance to ionizing radiation. Ny 6 and Ny 66 calendered fabrics are more sensitive even at low doses. Therefore, the effects of high energy irradiation on tyre cords have to be taken into consideration during tyre design reinforced with particularly Ny fabrics if pre-vulcanization with high energy radiation is to be applied.

  15. Effects of gamma and electron beam irradiation on the microbial quality of steamed tofu rolls

    International Nuclear Information System (INIS)

    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 D10 values of 0.20, 0.24 and 0.22 kGy for S. aureus, S. enteritidis and L. innocua, respectively. The respective D10 values for ebeam irradiation were 0.31, 0.35 and 0.27 kGy. Gamma and ebeam irradiation yielded D10 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 D10-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.

  16. Post-irradiation effect of Deuterium ion beam onto Rh/W/Cu multilayer thin film

    Energy Technology Data Exchange (ETDEWEB)

    Mostako, A.T.T. [Department of Physics, Indian Institute of Technology Guwahati, Guwahati 781039 (India); Khare, Alika, E-mail: alika@iitg.ernet.in [Department of Physics, Indian Institute of Technology Guwahati, Guwahati 781039 (India); Rao, C.V.S.; Vala, Sudhirsinh; Basu, T.K.; Raole, Prakash M.; Makwana, Rajinikant [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2014-03-15

    Graphical abstract: AFM images of M{sub 1} and M{sub 2} Rh/W/Cu multilayer samples are in Fig. (a and b) before D ion beam irradiation and that of after 20 keV and 30 keV D ion beam irradiation are in Fig. (c and d), respectively. The columnar structures observed in the AFM images before and after irradiation were intact. The RMS roughness of the films increased by ∼4 nm due to 20 keV and ∼3 nm due to 30 keV D ion beam irradiation. Display Omitted -- Abstract: The fabrication of mirror like multilayer Rh/W/Cu thin films via Pulsed Laser Deposition technique is reported in this paper. These multilayer thin film mirrors were irradiated to 10, 20 and 30 keV energy of Deuterium ion beam. The post-irradiation effects onto the quality of these thin films were investigated by subjecting them to X-ray Diffractometer, Scanning Electron Microscope, Atomic Force Microscope, Ultraviolet (UV)–Visible and Far Infrared (FIR) spectrometer.

  17. Separate, successive and simultaneous irradiation effects of electron beam and microwave on microorganisms survival

    International Nuclear Information System (INIS)

    The comparative results obtained by applying separate, successive and simultaneous electron beam (EB) irradiation and microwave (MW) heating in order to reduce the number of viable cells of Escherichia coli, Staphylococcus intermedius, Pseudomonas aeruginosa and Trichinella spiralis are presented. Simultaneous EB and MW irradiation results in a dramatic decrease of number of microorganisms compared to MW or EB irradiation alone. Thus, the number of viable cells of Staphylococcus intermedius was reduced by 5 order of magnitude more by simultaneous EB and MW irradiation than separate EB or MW irradiation. Electron beams destroy microorganisms by attacking the DNA molecule while microwaves, although the true mechanism is not clearly understood yet, can destroy the proteins of microorganisms. In our opinion, it seems that microwave irradiation could cause modification of the micro-organisms sensitivity to EB irradiation and thus the application of successive or simultaneous EB and MW irradiation lead to greater lethal effects than the EB irradiation alone. Experiments were carried out using a system consisting mainly of the following units: an accelerated electron beam source of 6 MeV and 75 mA current peak intensity, a 2.45 GHz microwave source of controlled power up to 0.85 kW and a special designed irradiation chamber. Irradiation chamber consists of a microwave multimode cavity in which the scanned electron beam is introduced perpendicularly to its upper-end plate through a 100 mm thick aluminium foil while the microwave power is coupled to one of its lateral walls via a slotted waveguide used as radiating antenna. The tests demonstrated that irradiation time and the upper limit of EB required absorbed dose, which ensures a complete sterilization effect, could be reduced of five to ten times by additional use of MW energy to EB irradiation. Also, EB costs could be much decreased and the application of low intensity radiation sources, which are less expensive, will

  18. 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.

  19. Effect of Scanning Beam Profile to Fabricate Fused Fiber Tapers by CO_2 Laser Irradiation Method

    Institute of Scientific and Technical Information of China (English)

    Bayle; Fabien; Luo; Aiping; Marin; Emmanuel; Meunier; Jean-Pierre

    2003-01-01

    Beam uniformity is a crucial building block of CO2 experiments aimed at fusing and stretching optical fibers in a lossless manner. When the irradiation beam is expanded through a galvanometer mirror, ways to achieve beam uniformity are investigated.

  20. Effect of Scanning Beam Profile to Fabricate Fused Fiber Tapers by CO2 Laser Irradiation Method

    Institute of Scientific and Technical Information of China (English)

    Bayle Fabien; Luo Aiping; Marin Emmanuel; Meunier Jean-Pierre

    2003-01-01

    Beam uniformity is a crucial building block of CO2 experiments aimed at fusing and stretching optical fibers in a lossless manner. When the irradiation beam is expanded through a galvanometer mirror, ways to achieve beam uniformity are investigated.

  1. The Effect of Pretreatment by using Electron Beam Irradiation on Oil Palm Empty Fruit Bunch

    Directory of Open Access Journals (Sweden)

    A. Kristiani

    2016-04-01

    Full Text Available Oil palm empty fruit bunch (OPEFB is a potential type of lignocellulosic biomass for second-generation bioethanol production. The pretreatment process is an important process in the series of processes to produce bioethanol. This research aims to study the effects of pretreatment process by using electron beam irradiation to OPEFB’s characterization as raw materials for the hydrolysis reaction to produce monomer sugars which will be fermented into ethanol. The untreated and treated OPEFB are characterized in terms of their physical and chemical properties. Analysis results of the compositional analysis by using NREL/TP-510-42618 method show that after pretreatment by using electron beam irradiation, OPEFB's total lignin content is changed little while its cellulose and hemicellulose contents tend to decrease with increasing irradiation dose. X-ray diffraction (XRD analysis shows that there is a decrease of crystallinity compared to untreated OPEFB, except for 200-kGy irradiated OPEFB. The highest decrease of crystallinity was shown by 300-kGy irradiated OPEFB. Further, crystallite sizes of treated OPEFBs are not significantly different from the untreated, except for the 200-kGy irradiated OPEFB. Irradiation pretreatment also increases specific surface area, pore volume, and pore size. The IR spectra analysis show the absorption of cellulose, hemicellulose, and lignin.

  2. Effects of electron beam irradiation on the structural properties of polylactic acid/polyethylene blends

    Science.gov (United States)

    Bee, Soo-Tueen; Ratnam, C. T.; Sin, Lee Tin; Tee, Tiam-Ting; Wong, Wai-Kien; Lee, Jiuun-Xiang; Rahmat, A. R.

    2014-09-01

    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.

  3. Effect of electron beam irradiation on conidial germination activity and pathogenicity of Botrytis cinerea

    International Nuclear Information System (INIS)

    Conidia of Botrytis cinerea were irradiated by electron beam at 0.5, 1.0, 2.0 and 3.0 kGy. The influence of electron beam on the activities of conidial germination and pathogenicity at the temperatures of 5 ℃ and 25 ℃ were tested, respectively. The results showed that the electron beam could inhibit germination of conidia and the length of germ tube of Botrytis cinerea, and delay the germination time. It could also decrease the pathogenicity obviously and higher irradiation dose showed stronger effects. Compared with control, the complete germination time of conidia extended to 5 and 9 d at the cultivate temperatures of 25 ℃ and 5 ℃, after 2 kGy of irradiation, and the germination rate was reduced 46.57% and 33.68%, respectively. The inhibition rates of germ tube were 25.12% and 74.29% when cultured 24 h. The pathogenicity of Botrytis cinerea to strawberry was reduced significantly. After 2.0 kGy irradiation and cultivate at 25 ℃ for 2 d, the disease index was 4.17 and it decreased to 15.28 after cultivation of 5 ℃ for 15 d. Electron beam treatment could inhibit the spore germination and germ tube elongation of Botrytis cinerea significantly, delayed the germination time, and reduced its pathogenicity, the higher the dose, the effect was more obvious. (authors)

  4. Gamma and electron beam irradiation effects on SiR-EPDM blends

    Directory of Open Access Journals (Sweden)

    R. Deepalaxmi

    2014-07-01

    Full Text Available Ethylene Propylene Diene Monomer (EPDM is widely used as Cable Insulation Material (CIM due to its good mechanical strength. Silicone Rubber (SiR is used in high temperature environments due to its good di-electric properties/hydrophobicity. The blending of SiR-EPDM may result in the improvement in their specific properties. The SiR-EPDM blend of equal composition (50:50 was prepared. When such blends are used as Cable Insulation Materials (CIM, they should perform their safety functions throughout their installed life in Nuclear Power Plants (NPP. The CIM will be exposed to Gamma irradiation at the installed locations. The short time accelerated testing was carried out, in order to forecast long-term performance of CIM. Electron beam irradiation is widely used in cable manufacturing industries to improve the performance of the polymeric materials. In the current study, on the purpose to investigate the effect of gamma/electron beam irradiation on the 50–50 composition of SiR-EPDM blend, blend was exposed to 25 Mrad dose of gamma/electron beam irradiation. The electrical and mechanical parameters like Volume Resistivity (VRY, Surface Resistivity (SRY, Tensile Strength (TS, Elongation at Break (EB, Hardness (H of the virgin, gamma/electron beam irradiated blends were determined as per ASTM/IEC standards. The nature of degradation was investigated using Fourier Transform Infrared Spectroscopy (FTIR. To determine the elemental composition of the materials at the surface, Energy Dispersive X-ray Analysis (EDAX has been done. Scanning Electron Microscopy (SEM analysis has been done to study the morphological changes. The occurrence of cross-linking is found to be the mechanism for ageing in gamma/electron beam irradiated SiR-EPDM blends.

  5. 50 MeV lithium ion beam irradiation effects in poly vinylidene fluoride (PVDF) polymer

    Indian Academy of Sciences (India)

    A K Srivastava; H S Virk

    2000-12-01

    Irradiation effects of 50 MeV 7Li+3 ion beam induced in bulk PVDF polymer have been studied with respect to their optical, chemical, structural and electrical behaviour by using UV-visible, FT-IR spectroscopy, XRD technique and electrical frequency response using LCR bridge. The ion fluences ranging from 1.27 × 1011 to 2.15 × 1013 ions cm–2 have been used to study dose effects of irradiation in PVDF. The recorded UV-visible spectra clearly shows five characteristic peaks at 315, 325, 360, 425 and 600 nm. Due to irradiation, the optical absorption initially decreases but then increases with higher fluences. In the FT-IR spectra, no appreciable change has been observed after irradiation, indicating that this polymer is chemically stable. There is exponential increase in admittance with log of frequency but the effect of irradiation is not quite appreciable. The value of tan and relaxation frequency are changed appreciably due to irradiation. The diffraction pattern of PVDF indicates that this polymer is in semi-crystalline form; a decrease in the crystallinity and crystallite size has been observed due to irradiation.

  6. Effect of electron beam irradiation on developmental stages of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

    International Nuclear Information System (INIS)

    Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), is an economically important and polyphagous pest, which harms various kinds of food crops and important agricultural plants, such as cotton and paprika. Effects of electron beam irradiation at six dose levels between 50 and 350 Gy on the egg (24–48 h old), the larval (4–5th instar), and the pupal (7-d old for female, 5-d old for male) development, and on the adult (1-d old) reproduction were tested to identify a potential quarantine treatment dose. Increased doses of irradiation on eggs decreased egg hatchability, pupation and adult emergence and increased larval period. ED99 values for inhibition of hatching, pupation and emergence were 460.6, 236.9 and 197.8 Gy, respectively. When larvae were irradiated with more than 280 Gy, no larvae could develop into pupae. ED99 values for inhibition of pupation and adult emergence were 265.6 and 189.6 Gy, respectively. Even though the irradiation on pupa did not completely inhibit adult emergence, most of the pupae emerged to deformed adults. When adults were irradiated, fecundity was not affected. However, F1 egg hatching was completely inhibited at the dose of 350 Gy. ED99 value for inhibition of adult emergence was estimated at 366.5 Gy. Our results suggest that electron beam irradiation could be recommendable as an alternative to MB and as a phytosanitary treatment for quarantine. A treatment dose of less than or equal to 220 Gy is suggested as a potential quarantine treatment to H. armigera egg for prevention of pupation and to larva for prevention of adult emerge. - Highlights: • Electron beam irradiation induced abnormal development of Helicoverpa armigera. • ED99 value for inhibition of adult emergence was estimated at 197.8 Gy for egg. • ED99 value for inhibition of adult emergence was estimated at 189.6 Gy for larva

  7. Effect of Electron-Beam Irradiation on Organic Semiconductor and Its Application for Transistor-Based Dosimeters.

    Science.gov (United States)

    Kim, Jae Joon; Ha, Jun Mok; Lee, Hyeok Moo; Raza, Hamid Saeed; Park, Ji Won; Cho, Sung Oh

    2016-08-01

    The effects of electron-beam irradiation on the organic semiconductor rubrene and its application as a dosimeter was investigated. Through the measurements of photoluminescence and the ultraviolet photoelectron spectroscopy, we found that electron-beam irradiation induces n-doping of rubrene. Additionally, we fabricated rubrene thin-film transistors with pristine and irradiated rubrene, and discovered that the decrease in transistor properties originated from the irradiation of rubrene and that the threshold voltages are shifted to the opposite directions as the irradiated layers. Finally, a highly sensitive and air-stable electron dosimeter was fabricated based on a rubrene transistor. PMID:27399874

  8. Effect of two steel plate's interface on heat transfer under laser beam irradiation

    CERN Document Server

    Zhao Jian Heng; Zhang Shi Wen; Gui Yuan Zhen; Wang Chun Yan; Tang Xiao Song; Zhang Da Yong

    2002-01-01

    It is supposed that there is a gap in the interface of two contacting steel plates due to thermal deformation under laser beam irradiation, and this gap will affect heat transfer in this interface obviously. This supposition is testified by experiments and simulation. This work is helpful to the study of the destruction mechanism under high power laser loading, and provides an effective way for anti-laser research

  9. Effect of electron beam irradiation on the properties of carbon fiber

    International Nuclear Information System (INIS)

    Carbon fibers are used as a reinforcement material in an epoxy matrix in advanced composites due to their high mechanical strength, rigidity and low specific density. An important aspect of the mechanical properties of composites is associated to the adhesion between the surface of the carbon fiber and the epoxy matrix. This paper aimed to evaluate the effects of electron beam irradiation on the physicochemical properties of carbon fibers to obtain better adhesion properties in resultant composite. Chemical structure and surface of carbon fiber were determined by FT-IR, elemental analysis and X-ray photoelectron spectroscopy, which indicated that the oxygen content increased significantly with increasing the radiation dose. Thermal stability of the carbon fibers was studied via the thermal gravimetric analysis. Surface morphology of carbon fiber was analyzed by scanning electron microscope. It was found that the degree of surface roughness was increased by electron beam irradiation

  10. Effect of electron beam irradiation on the structure and optical properties of nickel oxide nanocubes

    Indian Academy of Sciences (India)

    P A Sheena; K P Priyanka; N Aloysius Sabu; S Ganesh; Thomas Varghese

    2015-08-01

    This work reports the effect of electron beam (EB) irradiation on the structure and optical properties of nanocrystalline nickel oxide (NiO) cubes. NiO nanocubes were synthesized by the chemical precipitation method. The characterization was carried out by employing analytical techniques like X-ray diffraction, transmission electron microscopy, UV–visible and photoluminescence (PL) spectroscopy. The present investigation found that non-stoichiometry, defects and particle size variation caused by EB irradiation have a great influence on optical band gap, blue shift and band modification of absorption and PL spectra. Moreover, EB irradiation can result enhanced optical absorption performance and photo-activity in NiO nanocubes for optoelectronics and photo-catalytic applications. The study of International Commission on Illumination chromaticity diagram indicates that NiO can be developed as a suitable phosphor material for the application in near ultraviolet excited colour LEDs.

  11. Ion beam irradiation effects in strontium zirconium phosphate with NZP-structure type

    Energy Technology Data Exchange (ETDEWEB)

    Gregg, Daniel J., E-mail: daniel.gregg@ansto.gov.au [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Karatchevtseva, Inna; Thorogood, Gordon J.; Davis, Joel [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Bell, Benjamin D.C.; Jackson, Matthew [Department of Materials, Imperial College, London SW7 2BP (United Kingdom); Dayal, Pranesh [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Ionescu, Mihail [Institute of Environment Science, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Triani, Gerry; Short, Ken; Lumpkin, Gregory R.; Vance, Eric R. [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia)

    2014-03-15

    Ceramics with the sodium zirconium phosphate or NZP type structure have potential as nuclear waste form and inert matrix materials. For both applications the material will be subjected to self-radiation damage from α-decay of the incorporated actinides. In this study, ion-beam irradiation using Au- and He-ions has been used to simulate the consequences of α-decay and the effects of irradiation on the structural and macroscopic properties (density and hardness) have been investigated. Irradiation by Au-ions resulted in a significant volume contraction of ∼7%, a reduction in hardness of ∼30% and a loss in long-range order at fluences above 10{sup 14} Au-ions/cm{sup 2}. In contrast, little effect on the material properties was noted for samples irradiated with He-ions up to a fluence of 10{sup 17} ions/cm{sup 2}. Thermal annealing was investigated for the highest fluence Au-ion irradiated sample and significant decomposition was observed.

  12. Effect of electron beam irradiation on developmental stages of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

    Science.gov (United States)

    Kim, Junheon; Chung, Soon-Oh; Jang, Sin Ae; Jang, Miyeon; Park, Chung Gyoo

    2015-07-01

    Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), is an economically important and polyphagous pest, which harms various kinds of food crops and important agricultural plants, such as cotton and paprika. Effects of electron beam irradiation at six dose levels between 50 and 350 Gy on the egg (24-48 h old), the larval (4-5th instar), and the pupal (7-d old for female, 5-d old for male) development, and on the adult (1-d old) reproduction were tested to identify a potential quarantine treatment dose. Increased doses of irradiation on eggs decreased egg hatchability, pupation and adult emergence and increased larval period. ED99 values for inhibition of hatching, pupation and emergence were 460.6, 236.9 and 197.8 Gy, respectively. When larvae were irradiated with more than 280 Gy, no larvae could develop into pupae. ED99 values for inhibition of pupation and adult emergence were 265.6 and 189.6 Gy, respectively. Even though the irradiation on pupa did not completely inhibit adult emergence, most of the pupae emerged to deformed adults. When adults were irradiated, fecundity was not affected. However, F1 egg hatching was completely inhibited at the dose of 350 Gy. ED99 value for inhibition of adult emergence was estimated at 366.5 Gy. Our results suggest that electron beam irradiation could be recommendable as an alternative to MB and as a phytosanitary treatment for quarantine. A treatment dose of less than or equal to 220 Gy is suggested as a potential quarantine treatment to H. armigera egg for prevention of pupation and to larva for prevention of adult emerge.

  13. Effects of ion beam irradiation on adventitious shoot regeneration from in vitro leaf explants of Septennial ionahta

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, L.B. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China)]. E-mail: libinzhou@impcas.ac.cn; Li, W.J. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Ma, S. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Dong, X.C. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Yu, L.X. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Li, Q. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Zhou, G.M. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Gao, Q.X. [Institute of Cell Biology, School of Life Science, Lanzhou University, Southern Tianshui Road 222, Lanzhou 730000 (China)

    2006-03-15

    The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiation on adventitious shoots from in vitro leaf explants of two different Saintpaulia ionahta (Mauve and Indikon) cultivars were studied with regard to tissue increase, shoots differentiation and morphology changes in the shoots. The experimental results showed that the survival fraction of shoot formation for the Mauve and Indikon irradiated with the carbon ion beam at 20 Gy were 0.715 and 0.600, respectively, while those for both the cultivars exposed to the X-ray irradiation at the same dose were 1.000. Relative biological effectiveness (RBE) of Mauve with respect to X-ray was about two. Secondly, the percentage of regenerating explants with malformed shoots in all Mauve regenerating explants irradiated with carbon ion beam at 20 Gy accounted for 49.6%, while that irradiated with the same dose of X-ray irradiation was only 4.7%; as for Saintpaulia ionahta Indikon irradiated with 20 Gy carbon ion beam, the percentage was 43.3%, which was higher than that of X-ray irradiation. Last, many chlorophyll deficient and other varieties of mutants were obtained in this study. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the leaf explants of Saintpaulia ionahta is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy to 25 Gy for carbon ion beam irradiation.

  14. Effects of ion beam irradiation on adventitious shoot regeneration from in vitro leaf explants of Saintpaulia ionahta

    Science.gov (United States)

    Zhou, L. B.; Li, W. J.; Ma, S.; Dong, X. C.; Yu, L. X.; Li, Q.; Zhou, G. M.; Gao, Q. X.

    2006-03-01

    The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiation on adventitious shoots from in vitro leaf explants of two different Saintpaulia ionahta (Mauve and Indikon) cultivars were studied with regard to tissue increase, shoots differentiation and morphology changes in the shoots. The experimental results showed that the survival fraction of shoot formation for the Mauve and Indikon irradiated with the carbon ion beam at 20 Gy were 0.715 and 0.600, respectively, while those for both the cultivars exposed to the X-ray irradiation at the same dose were 1.000. Relative biological effectiveness (RBE) of Mauve with respect to X-ray was about two. Secondly, the percentage of regenerating explants with malformed shoots in all Mauve regenerating explants irradiated with carbon ion beam at 20 Gy accounted for 49.6%, while that irradiated with the same dose of X-ray irradiation was only 4.7%; as for Saintpaulia ionahta Indikon irradiated with 20 Gy carbon ion beam, the percentage was 43.3%, which was higher than that of X-ray irradiation. Last, many chlorophyll deficient and other varieties of mutants were obtained in this study. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the leaf explants of Saintpaulia ionahta is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy to 25 Gy for carbon ion beam irradiation.

  15. Effect of deuterium ion beam irradiation onto the mirror-like pulsed laser deposited thin films of rhodium

    Energy Technology Data Exchange (ETDEWEB)

    Mostako, A.T.T., E-mail: abu@iitg.ernet.in [Laser and Photonics Lab, Department of Physics, Indian Institute of Technology Guwahati, Guwahati 781039 (India); Khare, Alika [Laser and Photonics Lab, Department of Physics, Indian Institute of Technology Guwahati, Guwahati 781039 (India); Rao, C.V.S.; Vala, Sudhirsinh; Makwana, R.J.; Basu, T.K. [Neutronics Lab, Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2015-01-01

    Highlights: • Rh mirror like thin films are fabricated by PLD technique for FM application. • Rh thin film FMs are irradiated with 10, 20, and 30 keV D ion beam. • Effect of D ion beam irradiation on Rh FM’s reflectivity is investigated. - Abstract: The effect of deuterium ion beam irradiation on the reflectivity of mirror-like pulsed laser deposited (PLD) thin film of rhodium is reported. The deposition parameters; target-substrate distance and background helium gas pressure were optimized to obtain the good quality rhodium films, of higher thickness, oriented preferentially in (1 1 1) plane. The rhodium thin films deposited at optimum PLD parameters were exposed to 10, 20, and 30 keV deuterium ion beam. The changes in surface morphology and UV–Visible–FIR reflectivity of mirror-like rhodium thin films, as a function of energy of deuterium ion beam, after exposure are reported.

  16. In vivo 3D analysis of systemic effects after local heavy-ion beam irradiation in an animal model

    Science.gov (United States)

    Nagata, Kento; Hashimoto, Chika; Watanabe-Asaka, Tomomi; Itoh, Kazusa; Yasuda, Takako; Ohta, Kousaku; Oonishi, Hisako; Igarashi, Kento; Suzuki, Michiyo; Funayama, Tomoo; Kobayashi, Yasuhiko; Nishimaki, Toshiyuki; Katsumura, Takafumi; Oota, Hiroki; Ogawa, Motoyuki; Oga, Atsunori; Ikemoto, Kenzo; Itoh, Hiroshi; Kutsuna, Natsumaro; Oda, Shoji; Mitani, Hiroshi

    2016-01-01

    Radiotherapy is widely used in cancer treatment. In addition to inducing effects in the irradiated area, irradiation may induce effects on tissues close to and distant from the irradiated area. Japanese medaka, Oryzias latipes, is a small teleost fish and a model organism for evaluating the environmental effects of radiation. In this study, we applied low-energy carbon-ion (26.7 MeV/u) irradiation to adult medaka to a depth of approximately 2.2 mm from the body surface using an irradiation system at the National Institutes for Quantum and Radiological Science and Technology. We histologically evaluated the systemic alterations induced by irradiation using serial sections of the whole body, and conducted a heart rate analysis. Tissues from the irradiated side showed signs of serious injury that corresponded with the radiation dose. A 3D reconstruction analysis of the kidney sections showed reductions in the kidney volume and blood cell mass along the irradiated area, reflecting the precise localization of the injuries caused by carbon-beam irradiation. Capillary aneurysms were observed in the gill in both ventrally and dorsally irradiated fish, suggesting systemic irradiation effects. The present study provides an in vivo model for further investigation of the effects of irradiation beyond the locally irradiated area. PMID:27345436

  17. 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.

  18. Comparative study on the effect of electron beam irradiation on the physical properties of ethylene-vinyl acetate copolymer composites

    Science.gov (United States)

    Wang, Bibo; Hong, Ningning; Shi, Yongqian; Wang, Biao; Sheng, Haibo; Song, Lei; Tang, Qinbo; Hu, Yuan

    2014-04-01

    Ethylene-vinyl acetate copolymer (EVA) flame retarded by a combination of cellulose acetate butyrate (CAB) microencapsulated ammonium polyphosphate (MCAPP) and polyamide-6 (PA-6) have been crosslinked by high energy electron beam irradiation. The effect of high energy electron beam irradiation on the crosslinking degree, mechanical, electrical and thermal properties of EVA/MCAPP/PA-6 cable material was studied by gel content, heat extention test, mechanical test, dynamic mechanical analysis, high-insulation resistance meter and thermogravimetric analysis. The gel content and heat extention test results showed that the EVA/MCAPP/PA-6 composites can be easily crosslinked by electron beam irradiation. The tensile strength of EVA composites was drastically increased from 16.2 to maximum 26.2 MPa as the electron beam irradiation dose increases from 0 to 160 kGy. The volatilized products of EVA/MCAPP/PA-6 composites were analyzed and compared by thermogravimetric analysis/infrared spectrometry (TG-FTIR).

  19. Investigation of the combined effect of neutron irradiation and electron beam exposure on pure tungsten

    Science.gov (United States)

    Van Renterghem, W.; Uytdenhouwen, I.

    2016-08-01

    Pure tungsten samples were neutron irradiated in the BR2 reactor of SCK·CEN to fluences of 1.47 × 1020 n/cm2 and 4.74 × 1020 n/cm2 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 × 1021/m³ to 9 × 1022/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.

  20. Effects of Ion Beam Irradiation on Nanoscale InOx Cooper-Pair Insulators

    Directory of Open Access Journals (Sweden)

    Srdjan Milosavljević

    2013-01-01

    Full Text Available This paper examines the effects of irradiating indium oxide films of nanoscale thickness by ion beams, when these films are in the Cooper-pair insulator state. Radiation effects are predicted on the basis of Monte Carlo simulations of ion transport. Results of numerical experiments are interpreted within the theoretical model of a Cooper-pair insulator. The study suggests that radiation-induced changes in InOx films exposed to ion beams could significantly alter their current-voltage characteristics and that a transition to a metallic state is possible, due to radiation-induced perturbation of the fine-tuned granular structure. Furthermore, incident and displaced ions can break up enough Cooper pairs in InOx films to cause dissolution of this specific insulating state.

  1. Mutagenic effects of carbon ion beam irradiations on dry Lotus japonicus seeds

    Science.gov (United States)

    Luo, Shanwei; Zhou, Libin; Li, Wenjian; Du, Yan; Yu, Lixia; Feng, Hui; Mu, Jinhu; Chen, Yuze

    2016-09-01

    Carbon ion beam irradiation is a powerful method for creating mutants and has been used in crop breeding more and more. To investigate the effects of carbon ion beams on Lotus japonicus, dry seeds were irradiated by 80 MeV/u carbon ion beam at dosages of 0, 100, 200, 300, 400, 500 and 600 Gy. The germination rate, survival rate and root length of M1 populations were explored and the dose of 400 Gy was selected as the median lethal dose (LD50) for a large-scale mutant screening. Among 2472 M2 plants, 127 morphological mutants including leaf, stem, flower and fruit phenotypic variation were found, and the mutation frequency was approximately 5.14%. Inter simple sequence repeat (ISSR) assays were utilized to investigate the DNA polymorphism between seven mutants and eight plants without phenotypic variation from M2 populations. No remarkable differences were detected between these two groups, and the total polymorphic rate was 0.567%.

  2. Effects of electron-beam irradiation on some mechanical properties of polymer films

    Energy Technology Data Exchange (ETDEWEB)

    Zenkiewicz, M. E-mail: marianzenkiewicz@ic.torun.pl

    2004-04-01

    Effect of the electron-beam irradiation on the tensile strength at break, elongation at break, and tear resistance for packaging films made of low-density polyethylene (LDPE), biaxially oriented polypropylene (BOPP), and polyethylene terephthalate (PET) is discussed. The measurements in both the machine direction and the transverse direction were made. It was found that the electron irradiation caused an increase in the tear resistance of the LDPE film when doses of up to 100 kGy were applied. A significant decrease and even loss of the tear resistance of the films of BOPP and, partially, PET were observed at doses already below 25 kGy. This indicates that the BOPP and PET films when modified with the electron radiation can hardly be used in packaging.

  3. Study of the electron beam irradiation effect on some properties of aromatic aliphatic copolyester films

    International Nuclear Information System (INIS)

    Biodegradable and green plastics are the new tendency in the world. The effect of the electron beam irradiation in aromatic aliphatic copolyester and the blend with corn starch films (EcoflexR and EcobrasR) were studied by tensile strength at break, elongation at break, Scanning Electronic Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), crosslinking degree and biodegradability. The measurements in both, the machine direction and the transverse direction were made for mechanical tests. It was found that, the electron irradiation caused an increase in the strength at break of the blend with corn starch film, when doses of up to 10 kGy were applied. A significant decrease of the elongation at break of the blend with corn starch was observed at doses of 10 kGy and 40 kGy. It was not found important change in tensile properties for aromatic aliphatic copolyester. Structural changes of the samples (crosslinking or degradation) by SEM were not observed. The FT-IR identified the characteristic peaks of each involved functional group (copolyester and corn starch). However, it was not found bands of oxidation of the samples. In the DSC, changes in the melting temperature of the irradiated EcoflexR and EcobrasR samples, was not identified when compared with the samples of reference. However, it was verified a reduction in the melting enthalpy of the EcobrasR samples after irradiation. The EcobrasR material presented crosslinking, when submitted to doses of 10 kGy and 40 kGy. The EcoflexR material did not present crosslinking when submitted to these doses. The biodegradability of the materials was evaluated by two methods of test: soil simulated and enzymatic. In both methods, the irradiated samples presented faster biodegradation than the references not irradiated. (author)

  4. Effects of electron beam irradiation on elasticity of CFRTP (CF/PEEK)

    International Nuclear Information System (INIS)

    Homogeneous low voltage electron beam irradiation (HLEBI) improved the elasticity indicated by both flexural modulus (Ef) and the maximum slope value ((dσ/dε)max) of the bending stress-strain curve of carbon fiber reinforced thermoplastic polyetheretherketone (CFRTP) composite sheets with 0.50 mm thickness, although the penetration depth estimated was from 0.14 to 0.21 mm on both side surfaces. HLEBI remarkably enhanced both Ef and (dσ/dε)max. The Ef at middle cumulative probability (PE) of 0.50 for CFRTP irradiated at 0.30 MGy (kJg-1) was 3.3 GPa, which was 27% higher (2.6 GPa) than for CFRTP before irradiation. Moreover, (dσ/dε)max at middle cumulative probability (PE=0.50) was more than 4.9 GPa for CFRTP irradiated at 0.30 MGy. The interfacial friction force, as well as the strengthening of both carbon fiber and polyetheretherketone probably contributed to the HLEBI effects to enhance both Ef and (dσ/dε)max in the CFRTP. (author)

  5. Effects of heavy-ion beams irradiation on survival rate and antioxidant enzymes of sweet sorghum seedlings

    International Nuclear Information System (INIS)

    [Objective] This study aimed to investigate the effects of heavy-ion beams irradiation on the seed germination potential, survival rate, antioxidant enzyme activities and lipid peroxidation of sweet sorghum. [Method] The dry seeds were irradiated by 12C6+ heavy ion beams with absorbed doses: 0, 40, 80, 120, 160 and 200 Gy, respectively. Then, the seed germination potential, survival rate, antioxidant enzyme activities and lipid peroxidation of sweet sorghum were measured. [Result] Heavy-ion beams irradiation exhibited different influence on germination potential and survival rates. Germination rate showed a downward trend, but the corresponding survival curve of seedlings was saddle-shaped. The activities of SOD, POD, CAT and ASA-POD changed in different trends as well. The MDA content rose toward increasing irradiation dose, suggesting that high dose of heavy-ion beams irradiation enhanced the damage to membrane of sweet sorghum seedlings. [Conclusion] After being irradiated, germination potential and survival rates of sweet sorghum were decreased, and antioxidant enzymes activity changed greatly. This study laid the basis for further work on breeding and improvement of sweet sorghum irradiated by 12C6+ heavy ion beams

  6. Effects of electron beam irradiation on the dielectric properties of polyimide films

    International Nuclear Information System (INIS)

    Polyimide films have excellent thermal stability, reliable mechanical properties and low dielectric constant. Therefore, this material is widely used in many industrial fields such as microelectronics, flexible circuits, semiconductor products and aerospace materials. In space applications, earth-orbiting hardware operates in environments that generally include neutral particles, charged particles such as trapped protons and electrons, solar protons, and cosmic rays. Under these conditions, polyimide films were changed in the optical, electrical and mechanical properties. Therefore, in this study, we evaluated the effects of electron beam irradiation on polyimide. The O-H functional groups were created on the polyimide film surface in the results of FT-IR spectra. And it was found that the dielectric constants were changed as a function of electron beam dose

  7. Quality of electron beam irradiated strawberries

    International Nuclear Information System (INIS)

    Fresh 'Tristar' strawberries were treated by electron beam irradiation to determine the effects on postharvest quality attributes and shelf life. The intensity of red color rated by sensory panelists decreased as irradiation dosage increased from 0- to 2 kGy. Hunter 'L' values were higher for fruit treated with 2 kGy than for 0 and 0.5 kGy. Instron firmness values were lower for all irradiated fruit than for control fruit. Panelists rated irradiated fruit less firm than nonirradiated fruit stored 1, 2 and 4 days. An increase in off-flavor was noted among all treatments stored 6 and 8 days. Irradiation suppressed fungi on stored berries. Irradiation doses of 1 and 2 kGy extended shelf life 2 and 4 days, respectively. Electron beam irradiation technology has excellent potential for extension of shelf life of fresh strawberry fruits

  8. Effects of electron-beam irradiation on HDPE/Brazil nut shell fiber composite

    International Nuclear Information System (INIS)

    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)

  9. Effects of electron beam irradiated natural casings on the quality properties and shelf stability of emulsion sausage

    International Nuclear Information System (INIS)

    The effect of electron beam irradiated hog and sheep casings (1, 3, and 8 kGy) on the physicochemical properties and shelf stability of emulsion sausage was evaluated. There were no significant differences in pH, instrumental color, sensory properties (overall acceptability), and hardness between all the samples. The cooking yields for the irradiated treated samples were larger than that of the yields obtained for the non-irradiated samples for both the hog and sheep casing. The irradiated natural casings accelerated lipid oxidation, and inhibited the formation of volatile basic nitrogen and the increase in total aerobic bacteria. In conclusion, the natural casings irradiated below at a dose of 3 kGy had no effect on physicochemical and sensory properties of the emulsion sausages, however, that improved the shelf-stability over 5 weeks. Therefore, natural casings irradiated at moderate doses are suitable for sausage production. - Highlights: ► The effect of E-beam irradiated natural casings on sausage quality was evaluated. ► The use of irradiated casings improved shelf stability of sausage. ► Natural casings irradiated below 3 kGy are suitable for sausage production.

  10. Effects of Heavy-ion Beams Irradiation on Survival Rate and Antioxidant Enzymes of Sweet Sorghum Seedlings

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] This study aimed to investigate the effects of heavy-ion beams irradiation on the seed germination potential, survival rate, antioxidant enzyme activi- ties and lipid peroxidation of sweet sorghum. [Method] The dry seeds were irradiated by '2(36. heavy ion beams with absorbed doses: 0, 40, 80, 120, 160 and 200 Gy, respectively. Then, the seed germination potential, survival rate, antioxidant enzyme activities and lipid peroxidation of sweet sorghum were measured. [Result] Heavy-ion beams irradiation exhibited different influence on germination potential and survival rates. Germination rate showed a downward trend, but the corresponding survival curve of seedlings was saddle-shaped. The activities of SOD, POD, CAT and ASA- POD changed in different trends as well. The MDA content rose toward increasing irradiation dose, suggesting that high dose of heavy-ion beams irradiation enhanced the damage to membrane of sweet sorghum seedlings. [Conclusion] After being irra- diated, germination potential and survival rates of sweet sorghum were decreased, and antioxidant enzymes activity changed greatly. This study laid the basis for fur- ther work on breeding and improvement of sweet sorghum irradiated by ,^(12)C^(6+) heavy ion beams.

  11. Beam-Beam Effects

    CERN Document Server

    Herr, W

    2014-01-01

    One of the most severe limitations in high-intensity particle colliders is the beam-beam interaction, i.e. the perturbation of the beams as they cross the opposing beams. This introduction to beam-beam effects concentrates on a description of the phenomena that are present in modern colliding beam facilities.

  12. Effect of ion beam irradiation on metal particle doped polymer composites

    Indian Academy of Sciences (India)

    N L Singh; Sejal Shah; Anjum Qureshi; A Tripathi; F Singh; D K Avasthi; P M Raole

    2011-02-01

    Polymethyl methacrylate (PMMA) was prepared by solution polymerization method. Different concentrations (10, 20 and 40%) of Ni powder were dispersed in PMMA and the composite films were prepared by casting method. These films were irradiated with 120 MeV Ni$^{10+}$ ions at a fluence of 5 × 1012 ions/cm2. Electrical, structural and chemical properties of the composites were studied by means of an LCR meter, X-ray diffraction, FTIR spectroscopy and SEM/AFM, respectively. The results showed that the conductivity increases with metal concentration and also with ion beam irradiation. This reveals that ion beam irradiation promotes the metal/polymer bonding and converts polymeric structure into hydrogen depleted carbon network. It was observed from XRD analysis that percentage crystallinity and crystalline size decrease upon irradiation. This might be attributed to rupture of some polymeric bonds, which is also corroborated with FTIR spectroscopic analysis. Ion beam tempts graphitization of polymeric material by emission of hydrogen and/or other volatile gases. Surface morphology of the pristine and irradiated films was studied by atomic force microscopy (AFM)/scanning electron microscopy (SEM). Result showed that the surface roughness increases after ion beam irradiation.

  13. Effects of carbon ion beam irradiation on the shoot regeneration from in vitro axillary bud explants of the Impatiens hawkeri

    Science.gov (United States)

    Zhou, Libin; Zhou, Libin; Li, Wenjian; Li, Ping; Dong, Xicun; Qu, Ying; Ma, Shuang; Li, Qiang

    Accelerated ion beams is an excellent mutagen in plant breeding which can induce higher mutation frequencies and wider mutation spectrum than those of low linear energy transfer (LET) irradiations, such as X-rays (Okamura et al. 2003, Yamaguchi et al. 2003). Mutation breeding operation of two Saintpaulia ionahta cultivars using the method combining plant tissue culture technique and carbon ion beam irradiations were set out at Institute of Modern Physics from 2005 (Zhou et al. 2006). The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiations on regenerated shoots of Impatiens hawkeri from another kind of explants named in vitro axillary buds explants were studied recently. The biology endpoints in this study included relative number of roots (RNR), relative length of roots (RLR), relative height of shoots (RHS), relative number of nodes (RNN), survival fraction (SF) and morphology changes in the regenerated shoots. The experimental results showed that carbon ion beams inhibited the root and stem developments of axillary bud explants more severely than X-rays did. And the 50% lethal dose (LD50 ) is about 23.3 Gy for the carbon ion beam and 49.1 Gy for the X-rays, respectively. Relative biological effectiveness (RBE) of Impatiens hawkeri with respect to X-rays according to 50% SF was about two. Secondly, the percentage of shoots regenerated with malformed shoots including curliness, carnification, nicks in all Impatiens hawkeri axillary bud explants irradiated with carbon ion beam at 20 Gy accounted for 55.6%, while the highest number for the 40 Gy X-ray irradiation was 40%. Last, many regenerated shoots whose vascular bundle fused together were obtained only from explants irradiated with carbon ion beams. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the axillary explants of Impatiens hawkeri is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy

  14. Effect of ion and electron beam irradiation on surface morphology and optical properties of PVA

    Institute of Scientific and Technical Information of China (English)

    HM Eyssa; MO sman; SAK andil; MMA bdelrahman

    2015-01-01

    Polyvinyl alcohol (PVA) is a well-known friendly polymer for paper-making, textiles, and a variety of coat-ings, biomedical applications such as artificial pancreas, synthetic vitreous body, wound dressing, artificial skin, and cardiovascular device. In this paper, ion/electron beam is employed to get insight into the irradiation effect on surface morphology and optical properties of PVA polymer. UV-Vis spectra are recorded to investigate the effect of induced defects on the optical band gap and the formed carbon clusters size. Scanning electron microscopy (SEM) is used to relate and investigate surface morphology and optical properties of the target poly-mer with different doses (15, 30 and 60 min). Also, PVA polymer is subjected to theoretical studies by using semi-empirical PM7 quantum chemical method.

  15. Effect of electron beam irradiation on the degradation of monochlorophenols in aqueous solution

    Institute of Scientific and Technical Information of China (English)

    ADELEKE Olukunle Francis; ZHOU Rui-min; Zu Jian-hua; Ekoko Bakambo Gracien

    2005-01-01

    Electron beam was successfully used for the degradation of 2-chlorophenol (2-CP) and 4-chlorophenol (4-CP) in aqueous solutions in this research. The effect of radiation dose on substrate degradation and dechlorination of solutions with concentration of 50 mg/L was investigated. The effect of initial concentration, pH and presence of oxygen was also investigated. The concentration of 2-CP and 4-CP remaining in solution after irradiation were measured by HPLC. The results showed that increased radiation dose led to increased degradation of the chlorophenols and increased Cl- yield. Deaeration was also found to significantly increase the rate of degradation of chlorophenols in water while degradation and dechlorination under alkaline condition was lower than at low to neutral pH.

  16. Effect of sterilization dose on electron beam irradiated biodegradable polymers and coconut fiber based composites

    Energy Technology Data Exchange (ETDEWEB)

    Kodama, Yasko; Machado, Luci D.B., E-mail: ykodama@ipen.b, E-mail: lmachado@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Oishi, Akihiro; Nakayama, Kazuo, E-mail: a.oishi@aist.go.j, E-mail: kazuo-nakayama@jcom.home.ne.j [National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki-ken (Japan). Research Institute for Sustainable Chemical Innovation; Nagasawa, Naotsugu; Tamada, Masao, E-mail: nagasawa.naotsugu@jaea.go.j [Japan Atomic Energy Agency (JAEA), Gunma-ken (Japan). Quantum Beam Science Directorate

    2009-07-01

    In Brazil, annual production of coconut fruit is 1.5 billion in a cultivated area of 2.7 million ha. Coconut fiber applications as reinforcement for polymer composites, besides reducing the coconut waste, would reduce cost of the composite. On the other hand, biodegradable polymers have been receiving much attention due to the plastic waste problem. Poly(e-caprolactone), PCL, and poly(lactic acid), PLA, besides being biodegradable aliphatic polyesters, are biocompatible polymers. Considering the biomedical application of PLA and PCL, their products must be sterilized for use, and ionizing radiation has been widely used for medical devices sterilization. It is important to study the effect of ionizing radiation on the blends and composites due to the fact that they are based on biocompatible polymers. Is this research, hot pressed samples based on PLA:PCL (80:20, ratio of weight:weight) blend and the composites containing chemically treated or untreated coconut fiber (5, 10%) were irradiated by electron beams and gamma radiation from Co-60 source at doses in the range up to 200 kGy. Thermal mechanical analysis (TMA) and gel fraction measurements were performed in irradiated samples. From TMA curves it can be observed that thermal stability of samples with untreated coconut fiber slightly decreased with increasing fiber content. On the other hand, deformation increased with increasing fiber content. Acetylated coconut fibers slightly decreased thermal stability of samples. It seems that no interaction occurs between the natural fibers and the polymeric matrix due to irradiation. PLLA undergoes to main chain scission under ionizing irradiation according to thermal stability results and also because no gel fraction was observed. In contrast, PCL cross-linking is induced by ionizing radiation that increases thermal stability and decreases deformation. (author)

  17. Effect of sterilization dose on electron beam irradiated biodegradable polymers and coconut fiber based composites

    International Nuclear Information System (INIS)

    In Brazil, annual production of coconut fruit is 1.5 billion in a cultivated area of 2.7 million ha. Coconut fiber applications as reinforcement for polymer composites, besides reducing the coconut waste, would reduce cost of the composite. On the other hand, biodegradable polymers have been receiving much attention due to the plastic waste problem. Poly(e-caprolactone), PCL, and poly(lactic acid), PLA, besides being biodegradable aliphatic polyesters, are biocompatible polymers. Considering the biomedical application of PLA and PCL, their products must be sterilized for use, and ionizing radiation has been widely used for medical devices sterilization. It is important to study the effect of ionizing radiation on the blends and composites due to the fact that they are based on biocompatible polymers. Is this research, hot pressed samples based on PLA:PCL (80:20, ratio of weight:weight) blend and the composites containing chemically treated or untreated coconut fiber (5, 10%) were irradiated by electron beams and gamma radiation from Co-60 source at doses in the range up to 200 kGy. Thermal mechanical analysis (TMA) and gel fraction measurements were performed in irradiated samples. From TMA curves it can be observed that thermal stability of samples with untreated coconut fiber slightly decreased with increasing fiber content. On the other hand, deformation increased with increasing fiber content. Acetylated coconut fibers slightly decreased thermal stability of samples. It seems that no interaction occurs between the natural fibers and the polymeric matrix due to irradiation. PLLA undergoes to main chain scission under ionizing irradiation according to thermal stability results and also because no gel fraction was observed. In contrast, PCL cross-linking is induced by ionizing radiation that increases thermal stability and decreases deformation. (author)

  18. Green coffee decontamination by electron beam irradiation

    International Nuclear Information System (INIS)

    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

  19. Green coffee decontamination by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Nemtanu, Monica R. [National Institute for Lasers, Plasma and Radiation Physics, Department of Electron Accelerators, 409 Atomistilor St., P.O. Box MG-36, RO 76 900, Bucharest-Magurele (Romania)]. E-mail: monica@infim.ro; Brasoveanu, Mirela [National Institute for Lasers, Plasma and Radiation Physics, Department of Electron Accelerators, 409 Atomistilor St., P.O. Box MG-36, RO 76 900, Bucharest-Magurele (Romania); Grecu, Maria Nicoleta [National Institute for Materials Physics, RO 77 125, Bucharest-Magurele (Romania); Minea, R. [National Institute for Lasers, Plasma and Radiation Physics, Department of Electron Accelerators, 409 Atomistilor St., P.O. Box MG-36, RO 76 900, Bucharest-Magurele (Romania)

    2005-10-15

    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.

  20. Effects of Prenatal Irradiation with an Accelerated Heavy-Ion Beam on Postnatal Development in Rats

    Science.gov (United States)

    Wang, B.; Murakami, M.; Eguchi-Kasai, K.; Nojima, K.; Shang, Y.; Tanaka, K.; Fujita, K.; Coffigny, H.; Hayata, I.

    Effects on postnatal neurophysiological development in offspring were studied following exposure of pregnant Wistar rats to accelerated neon-ion beams with a LET value of about 30 keV mu m at a dose range from 0 1 Gy to 2 0Gy on the 15th day of gestation The age at which four physiologic markers appeared and five reflexes were acquired was examined prior to weaning Gain in body weight was monitored until the offspring were 3 months old Male offspring were evaluated as young adults using two behavioral tests The effects of X-rays at 200 kVp measured for the same biological end points were studied for comparison Our previous study on carbon-ion beams with a LET value of about 13 keV mu m was also cited to elucidate a possible LET-related effect For most of the endpoints at early age significant alteration was even observed in offspring prenatally received 0 1 Gy of accelerated neon ions while neither X rays nor carbon-ions under the same dose resulted in such a significant alteration compared to that from the sham-irradiated dams All offspring whose mothers received 2 0 Gy died prior to weaning Offspring from dams irradiated with accelerated neon ions generally showed higher incidences of prenatal death and preweaning mortality markedly delayed accomplishment in their physiological markers and reflexes and gain in body weight compared to those exposed to X-rays or carbon ions at doses of 0 1 to 1 5 Gy Significantly reduced ratios of main organ weight to body weight at postnatal ages of 30 60 and 90 days were also observed

  1. The effect of E-beam irradiation on the sterilization for calcium lactate

    International Nuclear Information System (INIS)

    The sterilization of calcium lactate as food additive was performed by electron beam. The quality, numbers of colony, gather mold and yeasts were determined before and after irradiation. It was found that the mortality of microbes significantly decreased with the increment of absorbed doses and the D10 value of colony number was determined to be 4.38 kGy. And the quality of calcium lactate satisfied the food standard though its mass fraction decreased a little after irradiation with electron beam of 10 kGy. (authors)

  2. Effects of electron beam irradiation on chemical composition, antinutritional factors, ruminal degradation and in vitro protein digestibility of canola meal

    Energy Technology Data Exchange (ETDEWEB)

    Taghinejad-Roudbaneh, M., E-mail: mtaghinejad@iaut.ac.i [Department of Animal Science, Faculty of Agriculture, Islamic Azad University, Tabriz Branch, P.O. Box 51589, Tabriz (Iran, Islamic Republic of); Ebrahimi, S.R. [Department of Animal Science, Faculty of Agriculture, Shahr-e-Qods Branch, Islamic Azad University, P.O. Box 37515-374, Shahr-e-Qods (Iran, Islamic Republic of); Azizi, S. [Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, P.O. Box 57155-1177, Urmia (Iran, Islamic Republic of); Shawrang, P. [Nuclear Science and Technology Research Institute, Agricultural, Medical and Industrial Research School, Atomic Energy Organization of Iran, P.O. Box 31485-498, Karaj (Iran, Islamic Republic of)

    2010-12-15

    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 (P<0.01). From in situ results, irradiation of canola meal at doses of 45 kGy decreased (P<0.05) the effective degradibility of crude protein (CP) by 14%, compared with an untreated sample. In vitro CP digestibility of EB-irradiated canola meal at doses of 15 and 30 kGy was improved (P<0.05). Electrophoresis results showed that napin and cruciferin sub-units of 30 and 45 kGy EB-irradiated canola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal.

  3. 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 ( P<0.01). From in situ results, irradiation of canola meal at doses of 45 kGy decreased ( P<0.05) the effective degradibility of crude protein (CP) by 14%, compared with an untreated sample. In vitro CP digestibility of EB-irradiated canola meal at doses of 15 and 30 kGy was improved ( P<0.05). Electrophoresis results showed that napin and cruciferin sub-units of 30 and 45 kGy EB-irradiated canola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal.

  4. A comparative study on the effects of electron beam irradiation on imidacloprid-resistant and -susceptible Aphis gossypii (Hemiptera: Aphididae)

    Science.gov (United States)

    Yun, Seung-Hwan; Koo, Hyun-Na; Lee, Seon-Woo; Kim, Hyun Kyung; Kim, Yuri; Han, Bumsoo; Kim, Gil-Hah

    2015-07-01

    The melon and cotton aphid, Aphis gossypii, is a polyphagous insect pest. This study compared the development, reproduction, DNA damage, recovery, and gene expression in imidacloprid-resistant (IMI-R) and -susceptible (S) strains of A. gossypii by electron beam irradiation. When 1st instar nymphs were irradiated with 100 Gy, the fecundity (nymphs of F1 generation) of the resultant adults were completely inhibited. When adults were irradiated with 200 Gy, the number of total 1st instar nymphs produced per adult was 3.0±1.7 and 1.9±1.4 in the S and IMI-R strains, respectively, but adult development was completely suppressed. However, electron beam irradiation did not affect adult longevity in either the S or IMI-R strain. There was no statistically significant difference between the effect of irradiation on the S and IMI-R strains. Therefore, electron beam irradiation at 200 Gy could be used as a phytosanitary irradiation treatment for both S and IMI-R strains of A. gossypii. The DNA damage caused by electron beam irradiation was evaluated by an alkaline comet assay. Exposure to an electron beam (50 Gy) induced DNA damage that was repaired to a similar level as the untreated control group (0 Gy) over time. However, at more than 100 Gy, the DNA damage was not completely repaired. The expression of P450, HSP70, cuticle protein, and elongation factor genes were higher in the IMI-R strain than in the S strain.

  5. Effectiveness of trimethylopropane trimethacrylate for the electron-beam-irradiation-induced cross-linking of polylactic acid

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Hon-Meng [Department of Chemical Engineering, Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Genting Kelang, 53300 Setapak, Kuala Lumpur (Malaysia); Bee, Soo-Tueen, E-mail: beest@utar.edu.my [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; Phang, Yee-Yao; Tee, Tiam-Ting [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)

    2014-01-15

    Highlights: • Investigation of trimethylopropane trimethacrylate (TMPTMA) on electron beam irradiated PLA. • Irradiated PLA blends were weakened by incorporation of high amount of TMPTMA. • TMPTMA interacts with polymer free radicals to build crosslinking network. -- Abstract: The purpose of this research was to investigate the effects of various loading levels of trimethylopropane trimethacrylate (TMPTMA) on the properties of polylactic acid (PLA) cross-linked via electron-beam irradiation. PLA was compounded with 3–5 wt.% of TMPTMA to induce cross-linking upon subjection to electron-beam irradiation doses of 25–250 kGy. The physical properties of the PLA samples were characterised by means of X-ray diffraction, gel fraction and scanning electron microscopy analyses on fractured surfaces after tensile tests. The presence of TMPTMA in PLA was found to effectively increase the crystallite size and gel fraction. However, higher loading levels of TMPTMA could compromise the properties of the PLA/TMPTMA samples, indicating that a larger amount of monomer free radicals might promote degradation within the substantially cross-linked amorphous phase. Irradiation-induced cross-linking in the samples could improve the cross-linking density while decreasing the elongation and interfering with the crystallisation. These effects are caused by the intensive irradiation-induced chain scission that is responsible for the deterioration of the mechanical and crystalline properties of the samples.

  6. Development of MeV cluster ion beams and irradiation effects

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Yuichi; Mizuhashi, Kiyoshi; Tajima, Satoshi; Arakawa, Kazuo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Hirata, Kouichi; Kobayashi, Yoshinori [National Inst. of Materials and Chemical Research, Tsukuba, Ibaraki (Japan)

    2001-02-01

    The production and acceleration of cluster ion beams were developed by using a sputtering ion source and a tandem accelerator. Molecular beams of iron oxides were produced from Fe{sub 2}O{sub 3} powder prepared as the specimen of the ion source and accelerated to energy of MeV range. Defect densities in silicon and polycarbonate targets by irradiation were compared between monoatomic carbon ions and carbon cluster beams (C{sub 2}-C{sub 4}). Beam currents by injection of carbon cluster beams (C{sub 8}) were measured for various targets such as Si, Al, Al{sub 2}O{sub 3} and polycarbonate. The target and time dependence of the beam currents were originated from sputtered ions due to water molecules and oxides adhered at the surface of the targets. (Y. Kazumata)

  7. Effectiveness of electron beam irradiation in the control of some soilborne pathogens

    International Nuclear Information System (INIS)

    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)

  8. Electron beam sterilization of medical products. The effects of irradiation on surgical rubber gloves

    International Nuclear Information System (INIS)

    Radiation damage of five commercially produced rubber gloves using electron beam and γ- rays from Cobalt-60 have been investigated in relation to radiation sterilization. Samples were irraadiated up to 100 kGy. The radiation damage of rubber gloves was ssmaller in electron beam than γ- rays. Good retention in tensile strength (T sub b) and elongation at break (E sub b) were observed even after six months storage. Higher beam currents (higher dose rate) above 5 mA was favourable for sterilization of rubber gloves because of smaller degradation. The tensile strength and elongation of the irradiated rubber gloves is still withinAM/N

  9. Effects of electron beam irradiation on the microbial growth and quality of beef jerky during storage

    International Nuclear Information System (INIS)

    Electron beam irradiation was applied to improve the microbial safety of beef jerky during storage. Beef jerky samples were irradiated at doses of 1, 3, 5, and 10 kGy and stored at 20 oC for 60 d. Microbiological data indicated that the populations of total aerobic bacteria significantly decreased with increasing irradiation dosage. In particular, the populations of total aerobic bacteria were significantly decreased by 1.76 log CFU/g at 10 kJ/m2, compared to the control. Color measurements showed reduced Hunter L and a values of beef jerky for all the treatments during storage, and the Hunter L, a, and b values of beef jerky were not significantly different among the treatments. Sensory evaluation results also showed that electron beam irradiation did not affect sensory scores in overall during storage. Therefore, the results suggest that electron beam irradiation could be useful in improving the microbial safety without impairing the quality of beef jerky during storage.

  10. Dose Rate Effects on The Radiation Oxidation of Polyethylene: Electron Beam vs Gamma Irradiation

    International Nuclear Information System (INIS)

    The yields and spatial distribution of the oxidation products stemming from the oxidation of LLPE films induced by 60-Co gamma and by irradiation with 300 kev, 0.3 mA electrons in the dose range 0.04 kGy/h - 0.6 kGy/h (gamma) and at 1.5 kGy/hr ( e-beam) have been determined by applying a methodology involving FTIR microscopy (carbonyl products, resolution 10 μ), iodometric analysis (peroxides). The FTIR and EPR spectroscopies coupled with the multilayer technique (resolution 25 μ) were also employed for carrying on measurements of the film depth profiles of peroxyl radicals and their alky radicals precursors, radical decay kinetics, 'free' and ' bound' hydroperoxides and alcools. With gamma radiations the products yields are enhanced following the decrease of the dose rate from 0.7 to 0.04 kGy/h without substantial effect on the film depth distributions which appear rather uniform. Using e-beam (dose rate 1.5 kGy/h) a low level concentration limit is attained confined within the first 50 μ which is about 1 order of magnitude smaller as compared to gamma. The mechanistic implications inherent to the experimental results as well as the practical consequences related to the use of radiooxidation as a tool for inducing graft copolymerization reactions are discussed

  11. Degradation and decoloration of textiles wastewater by electron beam irradiation: Effect of energy, current and absorbed dose

    Energy Technology Data Exchange (ETDEWEB)

    Bakar, Khomsaton Abu; Zulkafli,; Hashim, Siti A' aisah [Malaysian Nuclear Agency (Nuclear Malaysia), Bangi 43000 Kajang Selangor (Malaysia); Ahmad, Pauzi [Universiti Kebangsaan Malaysia, 43600 UKM, Bangi Selangor (Malaysia)

    2014-09-03

    In this study, electron beam accelerator (EB) was used to treat textiles wastewater from Rawang Industrial Park, Selangor. The objectives were to determine effective energy, beam current and absorbed dose required for decoloration and degradation of the textiles effluent. The textiles effluent was irradiated in a batch with various energy of 1MeV to 3MeV at constant beam current of 30mA. It was observed that removal of color and COD increases with higher beam energy. The EB energy of 1MeV effectively to removed 58% color and 19% COD. For textile effluent sample irradiated at fix energy of 1MeV and 3Mev but at different beam current 10mA, 20mA and 30mA. It was observed that removal of color and COD increases with the increased of beam current at each energy. However removal of color was significantly better at 1Mev as compared to 3Mev. In the case of textiles effluent, irradiated at doses of 17, 20,25,30, 35, 100 and 200kGy using 30 kW power of EB (1Mev, 30mA), results shows removal of BOD{sub 5}, COD and color were in the range 9%-33%, 14%-38% and 43%-78% respectively.

  12. The mass effect model of the survival rate's dose effect of organism irradiated with low energy ion beam

    International Nuclear Information System (INIS)

    The main characteristic of the low energy ions mutation is its mass deposition effect. Basing on the theory of 'double strand breaking' and the 'mass deposition effect', the authors suggests that the mass deposition products can repair or further damage the double strand breaking of DNA. According to this consideration the dose effect model of the survival rate of organism irradiated by low energy of N+ ion beam is deduced as: S exp{-p[αφ + βφ2-Rφ2exp(-kφ)-Lφ3exp(-kφ)]}, which can be called 'mass effect model'. In the low energy ion beam mutation, the dose effects of many survival rates that can not be imitated by previous models are successfully imitated by this model. The suitable application fields of the model are also discussed

  13. Effect of electron beam irradiation on the biodegradability of aromatic aliphatic copolyester film and their blend with corn starch

    International Nuclear Information System (INIS)

    Biodegradable and green plastics have been studied in the last years. The aim of this paper is to study the effect of electron beam irradiation on the biodegradability of aromatic aliphatic copolyester film and their blend with corn starch. The samples were irradiated at different doses 10 and 40 kGy in a linear accelerator. The biodegradability of the materials was evaluated by two methods: soil simulated and enzymatic. In the method enzymatic when it was used α-amylase, the irradiated samples presented faster biodegradation than the references non irradiated. The blend of aromatic aliphatic copolyester with corn starch (EcobrasR) irradiated presented a bigger biodegradability than the aromatic aliphatic copolyester (EcoflexR) film in both methods studied. (author)

  14. Role of isolated and clustered DNA damage and the post-irradiating repair process in the effects of heavy ion beam irradiation

    International Nuclear Information System (INIS)

    Clustered DNA damage is a specific type of DNA damage induced by ionizing radiation. Any type of ionizing radiation traverses the target DNA molecule as a beam, inducing damage along its track. Our previous study showed that clustered DNA damage yields decreased with increased linear energy transfer (LET), leading us to investigate the importance of clustered DNA damage in the biological effects of heavy ion beam radiation. In this study, we analyzed the yield of clustered base damage (comprising multiple base lesions) in cultured cells irradiated with various heavy ion beams, and investigated isolated base damage and the repair process in post-irradiation cultured cells. Chinese hamster ovary (CHO) cells were irradiated by carbon, silicon, argon and iron ion beams with LETs of 13, 55, 90 and 200 keV µm-1, respectively. Agarose gel electrophoresis of the cells with enzymatic treatments indicated that clustered base damage yields decreased as the LET increased. The aldehyde reactive probe procedure showed that isolated base damage yields in the irradiated cells followed the same pattern. To analyze the cellular base damage process, clustered DNA damage repair was investigated using DNA repair mutant cells. DNA double-strand breaks accumulated in CHO mutant cells lacking Xrcc1 after irradiation, and the cell viability decreased. On the other hand, mouse embryonic fibroblast (Mef) cells lacking both Nth1 and Ogg1 became more resistant than the wild type Mef. Thus, clustered base damage seems to be involved in the expression of heavy ion beam biological effects via the repair process. (author)

  15. Monte Carlo simulation of small OpenPET prototype with 11C beam irradiation: effects of secondary particles on in-beam imaging

    International Nuclear Information System (INIS)

    In-beam positron emission tomography (PET) can enable visualization of an irradiated field using positron emitters (β+ decay). In particle therapies, many kinds of secondary particles are produced by nuclear interactions, which affect PET imaging. Our purpose in this work was to evaluate effects of secondary particles on in-beam PET imaging using the Monte Carlo simulation code, Geant4, by reproducing an experiment with a small OpenPET prototype in which a PMMA phantom was irradiated by a 11C beam. The number of incident particles to the detectors and their spectra, background coincidence for the PET scan, and reconstructed images were evaluated for three periods, spill-time (beam irradiation), pause-time (accelerating the particles) and beam-off time (duration after the final spill). For spill-time, we tested a background reduction technique in which coincidence events correlated with the accelerator radiofrequency were discarded (RF gated) that has been proposed in the literature. Also, background generation processes were identified. For spill-time, most background coincidences were caused by prompt gamma rays, and only 1.4% of the total coincidences generated β+ signals. Differently, for pause-time and beam-off time, more than 75% of the total coincidence events were signals. Using these coincidence events, we failed to reconstruct images during the spill-time, but we obtained successful reconstructions for the pause-time and beam-off time, which was consistent with the experimental results. From the simulation, we found that the absence of materials in the beam line and using the RF gated technique improved the signal-to-noise ratio for the spill-time. From an additional simulation with range shifter-less irradiation and the RF gated technique, we showed the feasibility of image reconstruction during the spill-time. (paper)

  16. Triple ion beam irradiation facility

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, M.B.; Allen, W.R.; Buhl, R.A.; Packan, N.H.; Cook, S.W.; Mansur, L.K.

    1988-12-01

    A unique ion irradiation facility consisting of three accelerators is described. The accelerators can be operated simultaneously to deliver three ion beams on one target sample. The energy ranges of the ions are 50 to 400 keV, 200 keV to 2.5 MeV, and 1.0 to 5.0 MeV. Three different ions in the appropriate mass range can be simultaneously implanted to the same depth in a target specimen as large as 100 mm/sup 2/ in area. Typical depth ranges are 0.1 to 1.0 ..mu..m. The X-Y profiles of all three ion beams are measured by a system of miniature Faraday cups. The low-voltage accelerator can periodically ramp the ion beam energy during the implantation. Three different types of target chambers are in use at this facility. The triple-beam high-vacuum chamber can hold nine transmission electron microscopy specimens at elevated temperature during a irradiation by the three simultaneous beams. A second high-vacuum chamber on the medium-voltage accelerator beamline houses a low- and high-temperature translator and a two-axis goniometer for ion channeling measurements. The third chamber on the high-energy beamline can be gas-filled for special stressed specimen irradiations. Special applications for the surface modification of materials with this facility are described. Appendixes containing operating procedures are also included. 18 refs., 27 figs., 1 tab.

  17. Triple ion beam irradiation facility

    International Nuclear Information System (INIS)

    A unique ion irradiation facility consisting of three accelerators is described. The accelerators can be operated simultaneously to deliver three ion beams on one target sample. The energy ranges of the ions are 50 to 400 keV, 200 keV to 2.5 MeV, and 1.0 to 5.0 MeV. Three different ions in the appropriate mass range can be simultaneously implanted to the same depth in a target specimen as large as 100 mm2 in area. Typical depth ranges are 0.1 to 1.0 μm. The X-Y profiles of all three ion beams are measured by a system of miniature Faraday cups. The low-voltage accelerator can periodically ramp the ion beam energy during the implantation. Three different types of target chambers are in use at this facility. The triple-beam high-vacuum chamber can hold nine transmission electron microscopy specimens at elevated temperature during a irradiation by the three simultaneous beams. A second high-vacuum chamber on the medium-voltage accelerator beamline houses a low- and high-temperature translator and a two-axis goniometer for ion channeling measurements. The third chamber on the high-energy beamline can be gas-filled for special stressed specimen irradiations. Special applications for the surface modification of materials with this facility are described. Appendixes containing operating procedures are also included. 18 refs., 27 figs., 1 tab

  18. Pulsed EPR study of low-dose irradiation effects in L-alanine crystals irradiated with γ-rays, Ne and Si ion beams

    International Nuclear Information System (INIS)

    Low-dose irradiation effects in L-alanine single crystals irradiated with γ-rays, Ne and Si ion beams have been investigated by means of a two-pulse electron spin echo (ESE) technique. An effective phase memory time, TM, was measured from the first stable L-alanine radical, SAR1, and its complex relaxation mechanism is discussed. Both spectral and instantaneous diffusion contributions to the total effective relaxation rate have been extrapolated through the detection of the two-pulse ESE signal as a function of turning angle. The local microscopic concentration of paramagnetic centers C(ions)/C(γ-ray) for low-dose heavy-ion irradiation has been deduced from the corresponding spin-spin interaction

  19. Processing of diamond by laser beam irradiation

    Science.gov (United States)

    Yoshikawa, Masanori; Hirata, Atsushi

    1998-10-01

    YAG and ArF excimer laser beams, of which wavelengths are 1.06 micrometers and 193 nm respectively, have been applied to processing of a variety of diamonds. Cutting and smoothing of natural, CVD and sintered diamonds have been performed. CVD diamond films were prepared by arc discharge plasma jet CVD and microwave plasma CVD, and sintered diamonds contain metallic or ceramic binder have been used. Fundamental removal processes of diamond with YAG and ArF excimer laser have been investigated using natural single crystal and CVD diamonds in various atmospheres changing laser irradiation conditions such as average power, energy density and pulse repetition rates. Cutting of natural and CVD diamonds with YAG laser proceeds at higher peal power that occurs at lower pulse repetition rates. Smooth surfaces are obtained by excimer laser irradiation at the incident angle of 80 percent. In the cases of the processing with YAG laser, the effect of local heating by laser beam irradiation mainly assists the diamond processing, and diamond appears to be removed after graphitization and oxidization following vaporization in the atmosphere contains oxygen. The temperature measurement was carried out at backside of irradiation surface, and increase of temperature when YAG laser beam was irradiated was larger than that when excimer laser was irradiated. On the contrary, the detection of C, C2, C+, O2 and CO from the emission at the irradiation area with ArF excimer laser beam suggest that processing partly proceeds by the separation of carbon atoms from the surface of diamond after braking bonds between carbon atoms caused by laser beam. Cutting of sintered diamond with metallic binder was difficult because metallic binder remains in the groove while ceramic binder was easily removed. Processing technique using laser beams has been applied to surface planing, chip preparation and edge formation of CVD diamond and curved surface formation on sintered diamond. Surface planing was

  20. Effect of Anorganic Substance on Physical Properties of Poly (Butylene Succinate -co- Adipate) Irradiated by Electron Beam

    International Nuclear Information System (INIS)

    Poly(butylene succinate-co-adipate), PBSA were electron beam irradiated in the presence of inorganic materials. The samples gave high gel fraction by irradiation in the presence of 2% silicon dioxide and 2% carbon black. It was found that addition of carbon black (CB) was effective for improving the heat stability of the sample. This is because of three-dimensional carbon black- polymer networks. Irradiated PBSA sheets broke immediately at 110 oC with load 6.67 kgf/cm2, while irradiated the same sample mixed with 2% carbon black did not break at the same condition. Biodegradability of crosslinked PBSA by soil burial tests was accelerated by addition of carbon black. (author)

  1. Beam-beam effects

    Energy Technology Data Exchange (ETDEWEB)

    Zholents, A.

    1994-12-01

    The term beam-beam effects is usually used to designate different phenomena associated with interactions of counter-rotating beams in storage rings. Typically, the authors speak about beam-beam effects when such interactions lead to an increase of the beam core size or to a reduction of the beam lifetime or to a growth of particle`s population in the beam halo and a correspondent increase of the background. Although observations of beam-beam effects are very similar in most storage rings, it is very likely that every particular case is largely unique and machine-dependent. This constitutes one of the problems in studying the beam-beam effects, because the experimental results are often obtained without characterizing a machine at the time of the experiment. Such machine parameters as a dynamic aperture, tune dependencies on amplitude of particle oscillations and energy, betatron phase advance between the interaction points and some others are not well known, thus making later analysis uncertain. The authors begin their discussion with demonstrations that beam-beam effects are closely related to non linear resonances. Then, they will show that a non linearity of the space charge field is responsible for the excitation of these resonances. After that, they will consider how beam-beam effects could be intensified by machine imperfections. Then, they will discuss a leading mechanism for the formation of the beam halo and will describe a new technique for beam tails and lifetime simulations. They will finish with a brief discussion of the coherent beam-beam effects.

  2. Radiosensitizing effect of nitric oxide in tumor cells and experimental tumors irradiated with gamma rays and proton beams

    International Nuclear Information System (INIS)

    Nitric oxide (NO) has been reported to be a radiosensitizer of mammalian cells under hypoxic conditions. In a previous study, we demonstrated an enhancement in radiation response induced by NO in mouse tumor cells under aerobic conditions, with an increasing effect as a function of malignancy. The aim of the present study was to evaluate the effect of NO in tumor cells and in experimental tumors irradiated with γ rays and proton beams. Irradiations were performed with a 137Cs γ source and with proton beams generated by the TANDAR accelerator. Tumor cells were treated with the NO donor DETA-NO and the sensitizer enhancement ratio (SER) was calculated using the α parameter of the survival curve fitted to the linear-quadratic model. Tumor cells irradiated with protons were radio sensitized by DETA-NO only in the more malignant cells irradiated with low LET protons (2.69±0.08 keV/μm). For higher LET protons there were no radiosensitizing effect. For human tumor cells pre-treated with DETA-NO and irradiated with γ rays, a significantly greater effect was demonstrated in the malignant cells (MCF-7) as compared with the near normal cells (HBL-100). Moreover, a significant decrease in tumor growth was demonstrated in mice pre-treated with the NO donor spermine and irradiated with γ rays and low LET protons as compared with mice irradiated without pre-treatment with the NO donor. In conclusion, we demonstrated a differential effect of NO as a radiosensitizer of malignant cells, both with γ rays and low LET protons. This selectivity, coupled to the in vivo inhibition of tumor growth, is of great interest for the potential use of NO releasing agents in radiotherapy. (author)

  3. Effect of intense pulsed ion beams irradiation on the oxidation behavior of gamma sup ' -based superalloy

    CERN Document Server

    Zhang Hong Tao; Han Bao Xi; Yan Sha; Zhao Wei Jiang; Han Ya Fan

    2002-01-01

    Intense pulsed ion beams (IPIB) with three different power densities (25, 37.5 and 50 MW/cm sup 2) are employed for the surface treatment of gamma sup ' -based superalloy IC6. The influence of IPIB irradiation on the oxidation behavior of IC6 at 1100 degree sign C for up to 100 h is investigated. It is found that the phase states of IC6 are dramatically changed after IPIB irradiation and the oxidation behavior of the irradiated coupons depends greatly on the power density of IPIB. IPIB irradiation with a power density of 25 or 37.5 MW/cm sup 2 significantly reduces the oxidation rate with respect to the unirradiated coupon. The improvement of the oxidation resistance can be attributed to a change in the oxidation products from a three-layered scale of Ni-rich oxides for the unirradiated coupon to a two-layered scale of Mo- and Al-rich oxides. In contrast, IPIB irradiation with a power density of 50 MW/cm sup 2 proves to be detrimental, causing a higher oxidation rate. The oxidation mechanism for IPIB irradiat...

  4. Effects of O2+ ions beam irradiation on crystal structure of rare earth sesquioxides

    International Nuclear Information System (INIS)

    We report the results of ion irradiation influence on rare earth sesquioxides structure, which are materials of practical importance as a radiation resistant ceramics in nuclear applications. Y2O3, Gd2O3 and Er2O3 sesquioxides in the pellet form were irradiated by oxygen ions (O2+) beam with the energy of 30 keV and implantation fluence of 5 x 1020 m-2. Samples are characterized by Grazing Incidence X-ray Diffraction (GIXRD), Raman spectroscopy and atomic force microscopy (AFM). By GIXRD it was found partial transformation from cubic (C) to monoclinic (B) phase only in Gd2O3, induced by O2+ irradiation. This was confirmed by Raman spectroscopy. Although full phase transition from C to B phase in Y2O3 was not observed, the splitting and broadening of the main intensity Raman band for C phase could be explained by the stress and the disorder induced by the quenching. Analysis done by AFM showed changes in surface topology, i.e. values of average roughness (Ra) and root mean squared roughness (RMS) were significantly changed after irradiation for all samples. RMSs in Y2O3 before and after irradiation were 35 nm and 26 nm, respectively.

  5. Effects of gamma and electron beam irradiation on the survival of pathogens inoculated into sliced and pizza cheeses

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun-Joo [Department of Food Science and Technology, Chung-Ang University, Ansung, Gyunggi-do 456-756 (Korea, Republic of); Ham, Jun-Sang [Animal Products Processing Division, National Livestock Research Institute, RDA, Suwon 441-706 (Korea, Republic of); Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kim, Keehyuk [Department of Culinary Nutrition, Woosong University, Daejeon 300-718 (Korea, Republic of); Ha, Sang-Do [Department of Food Science and Technology, Chung-Ang University, Ansung, Gyunggi-do 456-756 (Korea, Republic of); Jo, Cheorun, E-mail: cheorun@cnu.ac.k [Department of Animal Science and Biotechnology, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2010-06-15

    The objective of this study was to identify the efficacy of gamma and electron beam irradiation of the food-borne pathogens (Listeria monocytogenes and Staphylococcus aureus) in sliced and pizza cheeses commercially available in the Korean market. Total aerobic bacteria and yeast/mold in the cheeses ranged from 10{sup 2} to 10{sup 3} Log CFU/g. Irradiation of 1 kGy for sliced cheese and 3 kGy for pizza cheese were sufficient to lower the total aerobic bacteria to undetectable levels (10{sup 1} CFU/g). Pathogen inoculation test revealed that gamma irradiation was more effective than electron beam irradiation at the same absorbed dose, and the ranges of the D{sub 10} values were from 0.84 to 0.93 kGy for L. monocytogenes and from 0.60 to 0.63 kGy for S. aureus. Results suggest that a low dose irradiation can improve significantly the microbial quality and reduce the risk of contamination of sliced and pizza cheeses by the food-borne pathogens which can potentially occur during processing.

  6. Effects of gamma and electron beam irradiation on the survival of pathogens inoculated into sliced and pizza cheeses

    Science.gov (United States)

    Kim, Hyun-Joo; Ham, Jun-Sang; Lee, Ju-Woon; Kim, Keehyuk; Ha, Sang-Do; Jo, Cheorun

    2010-06-01

    The objective of this study was to identify the efficacy of gamma and electron beam irradiation of the food-borne pathogens ( Listeria monocytogenes and Staphylococcus aureus) in sliced and pizza cheeses commercially available in the Korean market. Total aerobic bacteria and yeast/mold in the cheeses ranged from 10 2 to 10 3 Log CFU/g. Irradiation of 1 kGy for sliced cheese and 3 kGy for pizza cheese were sufficient to lower the total aerobic bacteria to undetectable levels (10 1 CFU/g). Pathogen inoculation test revealed that gamma irradiation was more effective than electron beam irradiation at the same absorbed dose, and the ranges of the D 10 values were from 0.84 to 0.93 kGy for L. monocytogenes and from 0.60 to 0.63 kGy for S. aureus. Results suggest that a low dose irradiation can improve significantly the microbial quality and reduce the risk of contamination of sliced and pizza cheeses by the food-borne pathogens which can potentially occur during processing.

  7. Recent advances in biological effect and molecular mechanism of arabidopsis thaliana irradiated by ion beams

    International Nuclear Information System (INIS)

    Newly research progresses were summarized in effect of ion beams on seed surface, biological effect, growth, development, gravitropism and so on. Furthermore, mutation molecular mechanism of Arabidopsis thaliana was discussed, for example, alteration of DNA bases, DNA damage, chromosomal recombination, characteristics of mutant transmissibility, etc. Meanwhile, the achievements of transfer- ring extraneous gene to Arabidopsis thaliana by ion beams were reviewed in the paper. At last, the future prospective are also discussed here in mutation molecular mechanism and the potential application of biological effect of heavy ion beams. (authors)

  8. Effectiveness of trimethylopropane trimethacrylate for the electron-beam-irradiation-induced cross-linking of polylactic acid

    Science.gov (United States)

    Ng, Hon-Meng; Bee, Soo-Tueen; Ratnam, C. T.; Sin, Lee Tin; Phang, Yee-Yao; Tee, Tiam-Ting; Rahmat, A. R.

    2014-01-01

    The purpose of this research was to investigate the effects of various loading levels of trimethylopropane trimethacrylate (TMPTMA) on the properties of polylactic acid (PLA) cross-linked via electron-beam irradiation. PLA was compounded with 3-5 wt.% of TMPTMA to induce cross-linking upon subjection to electron-beam irradiation doses of 25-250 kGy. The physical properties of the PLA samples were characterised by means of X-ray diffraction, gel fraction and scanning electron microscopy analyses on fractured surfaces after tensile tests. The presence of TMPTMA in PLA was found to effectively increase the crystallite size and gel fraction. However, higher loading levels of TMPTMA could compromise the properties of the PLA/TMPTMA samples, indicating that a larger amount of monomer free radicals might promote degradation within the substantially cross-linked amorphous phase. Irradiation-induced cross-linking in the samples could improve the cross-linking density while decreasing the elongation and interfering with the crystallisation. These effects are caused by the intensive irradiation-induced chain scission that is responsible for the deterioration of the mechanical and crystalline properties of the samples.

  9. Effects of APTEOS content and electron beam irradiation on physical and separation properties of hybrid nylon-66 membranes

    International Nuclear Information System (INIS)

    Highlights: ► Hybrid nylon-66 membranes were prepared using APTEOS and modified by EB irradiation. ► APTEOS increase the formation of cellular pores. ► EB irradiation causes the growth of dense layer. ► 10 wt% of APTEOS and irradiation at 70 kGy shows satisfactory separation of salt. - Abstract: Nylon-66 contains functional groups which form hydrogen bonds with inorganic silica networks and allow the creation of hybrid membranes. As a typical semicrystalline polymer, nylon-66 can be crosslinked through electron beam (EB) irradiation to form nanofiltration membranes. The effects of γ-aminopropyltriethoxylsilane (APTEOS) and EB irradiation on the physical and separation properties of nylon-66 membranes were studied in this work. Hybrid nylon-66 membranes were prepared by adding an APTEOS solution (5 wt%, 10 wt% and 20 wt%) into nylon-66 which was dissolved in formic acid. Before air drying, membranes were irradiated at 60 kGy, 70 kGy and 80 kGy. More cellular pores were formed in nylon-66 membranes with the addition of APTEOS. However, increased irradiation dose caused the formation of a dense layer in nylon-66 membranes. Crosslinked silica in nylon-66 membranes was confirmed by FT-IR and DMA, while XRD results showed that there was a high degree of crystallinity in some membranes after irradiation. With improvements in membrane pore size and the ratio of membrane thickness to porosity, nylon-66 membrane with 10 wt% of APTEOS irradiated at 70 kGy exhibited satisfactory permeability, excellent removal of neutral solutes and improved rejection of divalent ions.

  10. Effects of APTEOS content and electron beam irradiation on physical and separation properties of hybrid nylon-66 membranes

    Energy Technology Data Exchange (ETDEWEB)

    Linggawati, A. [Department of Chemical and Process Engineering, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Mohammad, A.W., E-mail: wahabm@eng.ukm.my [Department of Chemical and Process Engineering, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Leo, C.P. [School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300 Nibong Tebal, S.P.S., Penang (Malaysia)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer Hybrid nylon-66 membranes were prepared using APTEOS and modified by EB irradiation. Black-Right-Pointing-Pointer APTEOS increase the formation of cellular pores. Black-Right-Pointing-Pointer EB irradiation causes the growth of dense layer. Black-Right-Pointing-Pointer 10 wt% of APTEOS and irradiation at 70 kGy shows satisfactory separation of salt. - Abstract: Nylon-66 contains functional groups which form hydrogen bonds with inorganic silica networks and allow the creation of hybrid membranes. As a typical semicrystalline polymer, nylon-66 can be crosslinked through electron beam (EB) irradiation to form nanofiltration membranes. The effects of {gamma}-aminopropyltriethoxylsilane (APTEOS) and EB irradiation on the physical and separation properties of nylon-66 membranes were studied in this work. Hybrid nylon-66 membranes were prepared by adding an APTEOS solution (5 wt%, 10 wt% and 20 wt%) into nylon-66 which was dissolved in formic acid. Before air drying, membranes were irradiated at 60 kGy, 70 kGy and 80 kGy. More cellular pores were formed in nylon-66 membranes with the addition of APTEOS. However, increased irradiation dose caused the formation of a dense layer in nylon-66 membranes. Crosslinked silica in nylon-66 membranes was confirmed by FT-IR and DMA, while XRD results showed that there was a high degree of crystallinity in some membranes after irradiation. With improvements in membrane pore size and the ratio of membrane thickness to porosity, nylon-66 membrane with 10 wt% of APTEOS irradiated at 70 kGy exhibited satisfactory permeability, excellent removal of neutral solutes and improved rejection of divalent ions.

  11. WEBEXPIR: Windowless target electron beam experimental irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Dierckx, Marc [SCK-CEN, Boeretang 200, B-2400 Mol (Belgium); Schuurmans, Paul [SCK-CEN, Boeretang 200, B-2400 Mol (Belgium)], E-mail: paul.schuurmans@sckcen.be; Heyse, Jan; Rosseel, Kris; Tichelen, Katrien Van [SCK-CEN, Boeretang 200, B-2400 Mol (Belgium); Nactergal, Benoit; Vandeplassche, Dirk [IBA, Chemin du Cyclotron 3, BE-1348 Louvain-la-Neuve (Belgium); Aoust, Thierry [SCK-CEN, Boeretang 200, B-2400 Mol (Belgium); Abs, Michel [IBA, Chemin du Cyclotron 3, BE-1348 Louvain-la-Neuve (Belgium); Guertin, Arnaud; Buhour, Jean-Michel; Cadiou, Arnaud [SUBATECH, Ecole des Mines, 4 rue Alfred Kastler, BP 20722, F-44307 Nantes cedex (France); Abderrahim, Hamid Ait [SCK-CEN, Boeretang 200, B-2400 Mol (Belgium)

    2008-06-15

    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.

  12. WEBEXPIR: Windowless target electron beam experimental irradiation

    Science.gov (United States)

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

    2008-06-01

    The windowless target electron beam experimental irradiation (WEBEXPIR) program was set-up as part of the MYRRHA/XT-ADS R&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.

  13. The positive charging effect of dielectric films irradiated by a focused electron beam

    International Nuclear Information System (INIS)

    Space charge and surface potential profiles are investigated with numerical simulation for dielectric films of SiO2 positively charged by a focused electron beam. By combining the Monte Carlo method and the finite difference method, the simulation is preformed with a newly developed comprehensive two-dimensional model including electron scattering, charge transport and trapping. Results show that the space charge is distributed positively, like a semi-ellipsoid, within a high-density region of electrons and holes, but negatively outside the region due to electron diffusion along the radial and beam incident directions. Simultaneously, peak positions of the positive and negative space charge densities shift outwards or downwards with electron beam irradiation. The surface potential, along the radial direction, has a nearly flat-top around the center, abruptly decreases to negative values outside the high-density region and finally increases to zero gradually. Influences of electron beam and film parameters on the surface potential profile in the equilibrium state are also shown and analyzed. Furthermore, the variation of secondary electron signal of a large-scale integration sample positively charged in scanning electron microscopic observation is simulated and validated by experiment.

  14. Effects of electron beam irradiation on the property behaviour of poly(ether-block-amide) blended with various stabilisers

    International Nuclear Information System (INIS)

    Radiosterilisation can induce modifications and/or degradation to transpire in poly(ether-block-amide) (PEBA) following irradiation. The current investigation utilises combined synergistic mixtures of stabilisers to minimise these effects, by melt blending them with the PEBA material. Hindered amine stabilisers (HAS), primary antioxidants and secondary antioxidants were the stabilisers incorporate to reduce/eliminate the effects of 50 kGy electron beam irradiation dose on the material. Results were discussed by comparing the stabilising efficiency of mixtures on the PEBA material in contrast to the control sample. Dynamic frequency sweeps demonstrated the formation of crosslinks, where the degree of crosslinking was dependent on the combination of stabilisers mixed in the base material (PEBA). The storage modulus displayed that PEBA blended with Irganox 565 had very slight changes in contrast to all other samples following irradiation. However, since this sample is a phenol containing system, severe discolouration was observed in comparison to other samples due to the oxidation of the hindered phenol. Overall, this study provides compelling evidence that a combined synergistic mixture of Irganox 565 (multifunctional phenolic antioxidant) and Tinuvin 783 (hindered amide light stabiliser) with PEBA, resulted in the best radiation stability. - Highlights: • PEBA was melt blended with various stabilisers. • All virgin and blended PEBA samples were exposed to electron beam irradiation. • The incorporation of stabilisers into the PEBA material resulted in discolouration. • PEBA blended with Irganox 565 and Tinuvin 783 improved the radiation resistance

  15. Effects of Electron Beam Irradiation on the Magnetic Properties of Nickel Ferrite (NiFe2O4) Nanoparticles

    International Nuclear Information System (INIS)

    The effects of electron beam irradiation on the magnetic properties of Nickel Ferrite (NiFe2O4) nanoparticles in doses of 0, 100 and 200 kGy was analyzed. The values of saturation magnetization (MS) results at room temperature increased from 31.33, 35.12 and 39.36 emu/ g respectively. Xray diffraction (XRD) analysis of the samples showed that the crystallite size of the particles decreased from 13.16 nm to 7.52 nm with increasing doses of irradiation. The lattice parameter of the cubic structure decreases with increasing irradiation doses, due to ionisation of Fe2+ to Fe3+ producing a closed packing in the cubic crystal structure. (author)

  16. The effect of electron beam irradiation on properties of virgin and glass fiber-reinforced polyamide 6

    Science.gov (United States)

    Porubská, Mária; Janigová, Ivica; Jomová, Klaudia; Chodák, Ivan

    2014-09-01

    Crosslinking of virgin polyamide 6 (PA-6) and PA-6 filled with 30 wt% glass fibers (GF) was investigated. The crosslinking was initiated by electron irradiation applying dose ranging from 50 to 500 kGy. The gel point was determined to be 200 kGy for both materials. The results obtained indicate that the GF presence may retard gel formation in the PA-matrix. The irradiation of unfilled PA-6 resulted in an increase in tensile strength at break and Young's moduli (a minimum 50% gel content is needed), tensile properties at yield were not affected by crosslinking. Thermal resistance, as measured by the heat deflection temperature and Vicat softening temperature, was affected only marginally. Considering these effects, electron beam irradiation is found to be more beneficial for the virgin PA than for the corresponding PA/GF composite.

  17. Effects of the irradiation of a finite number of laser beams on the implosion of a cone-guided target

    Science.gov (United States)

    Yanagawa, T.; Sakagami, H.; Nagatomo, H.; Sunahara, A.

    2016-03-01

    In direct drive laser fusion, the non-uniformity of the laser absorption on the target surface caused by the irradiation of a finite number of laser beams is a sever problem. GekkoXII laser at Osaka University has twelve laser beams and is irradiated to the target with a dodecahedron orientation, in which the distribution of the laser absorption on the target surface becomes non-uniform. Furthermore, in the case of a cone-guided target, the laser irradiation orientation is more limited. In this paper, we conducted implosion simulations of the cone- guided target based on GekkoXII irradiation orientation and compared the case of using the twelve beams and nine beams where the three beams irradiating the cone region are cut. The implosion simulations were conducted by a three-dimensional pure hydro code.

  18. Ion-beam irradiation of Co/Cu nanostructures: Effects on giant magnetoresistance and magnetic properties

    International Nuclear Information System (INIS)

    We have studied the effects of ion irradiation at low doses (14 ions/cm2) on the structural properties, giant magnetoresistance (GMR), and interlayer magnetic coupling in Co/Cu multilayers. X-ray analysis combined with magnetic and resistivity measurements reveal that intermixing is promoted by ion irradiation while the periodic structure and crystallographic properties of the multilayers are not significantly altered. The GMR ratio of a multilayer decreases monotonically with ion dose. However, thermal annealing on an irradiated multilayer results in sharp recovery of the reduced GMR, and can be associated with a backdiffusion process in metastably intermixed regions. Hence, using ion irradiation and subsequent annealing, the GMR of a single multilayer can be altered reversibly over a wide range. The variation of GMR upon irradiation (or annealing) is accompanied by significant suppression (or improvement) of the antiferromagnetic interlayer coupling. The correlation between GMR and AF coupling, as well as the role of enhanced electron scattering at interfaces during these processes are discussed

  19. Investigation of electron beam irradiation effects on anti-nutritional factors, chemical composition and digestion kinetics of whole cottonseed, soybean and canola seeds

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahimi-Mahmoudabad, S.R., E-mail: ebrahimiyazd@yahoo.com [Department of Animal Science, Faculty of Agriculture, Shahr-e-Qods Branch, Islamic Azad University, P.O. Box 37515-374, Shahr-e-Qods (Iran, Islamic Republic of); Taghinejad-Roudbaneh, M. [Department of Animal Science, Faculty of Agriculture, Tabriz Branch, Islamic Azad University, P.O. Box 51589, Tabriz (Iran, Islamic Republic of)

    2011-12-15

    This study was completed to determine effects of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on anti-nutritional factors, ruminal degradation and in vitro crude protein (CP) digestibility of whole cottonseed (WCS), soybean (SB) and canola seeds (CS). EB-irradiation eliminated completely (P<0.001) phytic acid of WCS, SB and CS at a dose of 30 kGy. EB-irradiation decreased linearly (P<0.001) the total glucosinolate content of CS. Trypsin inhibitor activity of 15, 30 and 45 kGy EB-irradiated SB was decreased by 19, 73 and 88%, respectively. Free gossypol content of WCS was reduced linearly (P<0.001) by irradiation. EB-irradiation increased linearly (P<0.001) CP digestibility of feeds. In conclusion, EB-irradiation was an effective processing method for improving the nutritive value of WCS, SB and CS. - Highlights: > Effects of electron beam (EB) irradiation on nutritive value of some oilseeds were evaluated. > EB-irradiation eliminated completely phytic acid of seeds at a dose of 30 kGy. > EB-irradiation decreased trypsin inhibitor activity of soybean. > Free gossypol content of whole cottonseed was reduced linearly by EB-irradiation. > EB-irradiation increased escape protein and crude protein digestibility of seeds.

  20. Investigation of electron beam irradiation effects on anti-nutritional factors, chemical composition and digestion kinetics of whole cottonseed, soybean and canola seeds

    International Nuclear Information System (INIS)

    This study was completed to determine effects of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on anti-nutritional factors, ruminal degradation and in vitro crude protein (CP) digestibility of whole cottonseed (WCS), soybean (SB) and canola seeds (CS). EB-irradiation eliminated completely (P<0.001) phytic acid of WCS, SB and CS at a dose of 30 kGy. EB-irradiation decreased linearly (P<0.001) the total glucosinolate content of CS. Trypsin inhibitor activity of 15, 30 and 45 kGy EB-irradiated SB was decreased by 19, 73 and 88%, respectively. Free gossypol content of WCS was reduced linearly (P<0.001) by irradiation. EB-irradiation increased linearly (P<0.001) CP digestibility of feeds. In conclusion, EB-irradiation was an effective processing method for improving the nutritive value of WCS, SB and CS. - Highlights: → Effects of electron beam (EB) irradiation on nutritive value of some oilseeds were evaluated. → EB-irradiation eliminated completely phytic acid of seeds at a dose of 30 kGy. → EB-irradiation decreased trypsin inhibitor activity of soybean. → Free gossypol content of whole cottonseed was reduced linearly by EB-irradiation. → EB-irradiation increased escape protein and crude protein digestibility of seeds.

  1. Combined effects of nuclear and electronic energy losses in solids irradiated with a dual-ion beam

    Science.gov (United States)

    Thomé, Lionel; Debelle, Aurélien; Garrido, Frédérico; Trocellier, Patrick; Serruys, Yves; Velisa, Gihan; Miro, Sandrine

    2013-04-01

    Single and dual-beam irradiations of oxide (c-ZrO2, MgO, Gd2Ti2O7) and carbide (SiC) single crystals were performed to study combined effects of nuclear (Sn) and electronic (Se) energy losses. Rutherford backscattering experiments in channeling conditions show that the Sn/Se cooperation induces a strong decrease of the irradiation-induced damage in SiC and MgO and almost no effects in c-ZrO2 and Gd2Ti2O7. The healing process is ascribed to electronic excitations arising from the electronic energy loss of swift ions. These results present a strong interest for both fundamental understanding of the ion-solid interactions and technological applications in the nuclear industry where expected cooperative Sn/Se effects may lead to the preservation of the integrity of nuclear devices.

  2. Effect of Hydrogen ion beam irradiation onto the FIR reflectivity of pulsed laser deposited mirror like Tungsten films

    Energy Technology Data Exchange (ETDEWEB)

    Mostako, A.T.T. [Department of Physics, Indian Institute of Technology Guwahati, Guwahati 781 039 (India); Khare, Alika, E-mail: alika@iitg.ernet.in [Department of Physics, Indian Institute of Technology Guwahati, Guwahati 781 039 (India); Rao, C.V.S.; Raole, Prakash M.; Vala, Sudhirsinh; Jakhar, Shrichand; Basu, T.K.; Abhangi, Mitul; Makwana, Rajinikant J. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India)

    2012-04-15

    Graphical abstract: The specular FIR reflectivity of the W{sub 1}, W{sub 2}, W{sub 3} and W{sub 4} mirrors before and after 8 keV Hydrogen ion beam irradiation. Highlights: Black-Right-Pointing-Pointer Mirror like W thin films were obtained via PLD. Black-Right-Pointing-Pointer The maximum thickness of the Tungsten thin film was {approx}324 nm. Black-Right-Pointing-Pointer Effect of H-ion beam irradiation on the quality of PLD W mirror is reported. Black-Right-Pointing-Pointer Post exposure reflectivity of Tungsten thin films was hardly changed by 2%. - Abstract: The optical quality of the First Mirrors (FMs) of a fusion device (burning plasma experiments, ITER) deteriorates due to the erosion by charge exchange neutrals, re-deposition of the eroded material and the lattice damage by the bombardment of the high energetic particles. This degradation of the optical quality of the plasma facing components in such a harsh environment is a serious concern for the reliability of the spectroscopic based optical diagnostics using FM of a fusion device. In this paper, the effect of 8 keV Hydrogen ion beam irradiation onto the FIR reflectivity of Tungsten thin film mirror is presented. The Tungsten thin films were prepared via Pulsed Laser Deposition (PLD) technique. The Tungsten mirrors were subjected to X-ray Diffraction (XRD), Energy Dispersive X-ray (EDX), Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) for characterization. The specular reflectivities of the Tungsten mirrors before and after exposure to ion beam were recorded with Fourier Transform of Infra-Red (FTIR) technique. The ion penetration depth and straggle into Tungsten thin film and stainless steel (SS) substrate were estimated by Transport of Ions in Matter (TIRM) simulation code. The changes in post exposure IR reflectivity were interpreted in terms of these parameters.

  3. Effect of 8 MeV electron beam irradiation on the structural and optical properties of CeO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Babitha, K.K.; Priyanka, K.P. [Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College, Muvattupuzha, 686 661, Kerala (India); Sreedevi, A. [Department of Applied Science and Humanities, Thejus Engineering College, Thrissur, 680584 Kerala (India); Ganesh, S. [Microtron Centre, Mangalore University, Mangalagangotri, 574 199 Karnataka (India); Varghese, Thomas, E-mail: nanoncm@gmail.com [Nanoscience Research Centre (NSRC), Department of Physics, Nirmala College, Muvattupuzha, 686 661, Kerala (India)

    2014-12-15

    The effect of 8 MeV electron beam irradiation on the structural and optical properties of cerium oxide nanoparticles was investigated. Ceria nanoparticles were synthesized by chemical precipitation method, and characterized by X-ray diffraction, transmission electron microscopy, ultraviolet–visible, photoluminescence and Raman spectroscopy. Ultraviolet–visible absorption spectra, photoluminescence and Raman spectra of beam irradiated samples were modified, and shifted to blue region, which were attributed to quantum size effect. Systematic observations found that nonstoichiometry, defects and size reduction caused by beam irradiation have great influence on optical band gap, blue shift, photoluminescence and Raman band modifications. Moreover, electron beam irradiation is a suitable technique to enhance the structural and optical properties of nanoceria by controlling the particle size, which may lead to potentially useful technological applications. - Highlights: • Investigated effect of beam irradiation on CeO{sub 2} nanoparticles • Beam irradiation caused size reduction and surface modification. • It increases microstrain, decreases d-spacing and broadens XRD peaks. • It also modifies optical band gap, absorption, PL and Raman bands.

  4. Electron-beam irradiation inactivation of Salmonella: Effects on innate immunity and induction of protection against Salmonella enterica serovar Typhimurium challenge of chickens

    Science.gov (United States)

    Our laboratories are investigating the use of high-energy (10 MeV) Electron-Beam (E-beam) irradiation for its potential use in vaccine development. Ionizing radiation inactivates microorganisms by “direct and indirect” effects on nucleic acids and other cellular components. Though the cells are in...

  5. Effects of Alpha Particle and Proton Beam Irradiation as Putative Cross-Talk between A549 Cancer Cells and the Endothelial Cells in a Co-Culture System

    Directory of Open Access Journals (Sweden)

    Hélène Riquier

    2015-03-01

    Full Text Available Background: High-LET ion irradiation is being more and more often used to control tumors in patients. Given that tumors are now considered as complex organs composed of multiple cell types that can influence radiosensitivity, we investigated the effects of proton and alpha particle irradiation on the possible radioprotective cross-talk between cancer and endothelial cells. Materials and Methods: We designed new irradiation chambers that allow co-culture study of cells irradiated with a particle beam. A549 lung carcinoma cells and endothelial cells (EC were exposed to 1.5 Gy of proton beam or 1 and 2 Gy of alpha particles. Cell responses were studied by clonogenic assays and cell cycle was analyzed by flow cytometry. Gene expression studies were performed using Taqman low density array and by RT-qPCR. Results: A549 cells and EC displayed similar survival fraction and they had similar cell cycle distribution when irradiated alone or in co-culture. Both types of irradiation induced the overexpression of genes involved in cell growth, inflammation and angiogenesis. Conclusions: We set up new irradiation chamber in which two cell types were irradiated together with a particle beam. We could not show that tumor cells and endothelial cells were able to protect each other from particle irradiation. Gene expression changes were observed after particle irradiation that could suggest a possible radioprotective inter-cellular communication between the two cell types but further investigations are needed to confirm these results.

  6. Effects of Alpha Particle and Proton Beam Irradiation as Putative Cross-Talk between A549 Cancer Cells and the Endothelial Cells in a Co-Culture System

    Energy Technology Data Exchange (ETDEWEB)

    Riquier, Hélène; Abel, Denis [URBC-NARILIS, University of Namur, 61 rue de Bruxelles, Namur 5000 (Belgium); Wera, Anne-Catherine; Heuskin, Anne-Catherine [LARN-PMR, NARILIS, University of Namur, Namur 5000 (Belgium); Genard, Géraldine [URBC-NARILIS, University of Namur, 61 rue de Bruxelles, Namur 5000 (Belgium); Lucas, Stéphane [LARN-PMR, NARILIS, University of Namur, Namur 5000 (Belgium); Michiels, Carine, E-mail: carine.michiels@unamur.be [URBC-NARILIS, University of Namur, 61 rue de Bruxelles, Namur 5000 (Belgium)

    2015-03-18

    Background: High-LET ion irradiation is being more and more often used to control tumors in patients. Given that tumors are now considered as complex organs composed of multiple cell types that can influence radiosensitivity, we investigated the effects of proton and alpha particle irradiation on the possible radioprotective cross-talk between cancer and endothelial cells. Materials and Methods: We designed new irradiation chambers that allow co-culture study of cells irradiated with a particle beam. A549 lung carcinoma cells and endothelial cells (EC) were exposed to 1.5 Gy of proton beam or 1 and 2 Gy of alpha particles. Cell responses were studied by clonogenic assays and cell cycle was analyzed by flow cytometry. Gene expression studies were performed using Taqman low density array and by RT-qPCR. Results: A549 cells and EC displayed similar survival fraction and they had similar cell cycle distribution when irradiated alone or in co-culture. Both types of irradiation induced the overexpression of genes involved in cell growth, inflammation and angiogenesis. Conclusions: We set up new irradiation chamber in which two cell types were irradiated together with a particle beam. We could not show that tumor cells and endothelial cells were able to protect each other from particle irradiation. Gene expression changes were observed after particle irradiation that could suggest a possible radioprotective inter-cellular communication between the two cell types but further investigations are needed to confirm these results.

  7. Effects of Alpha Particle and Proton Beam Irradiation as Putative Cross-Talk between A549 Cancer Cells and the Endothelial Cells in a Co-Culture System

    International Nuclear Information System (INIS)

    Background: High-LET ion irradiation is being more and more often used to control tumors in patients. Given that tumors are now considered as complex organs composed of multiple cell types that can influence radiosensitivity, we investigated the effects of proton and alpha particle irradiation on the possible radioprotective cross-talk between cancer and endothelial cells. Materials and Methods: We designed new irradiation chambers that allow co-culture study of cells irradiated with a particle beam. A549 lung carcinoma cells and endothelial cells (EC) were exposed to 1.5 Gy of proton beam or 1 and 2 Gy of alpha particles. Cell responses were studied by clonogenic assays and cell cycle was analyzed by flow cytometry. Gene expression studies were performed using Taqman low density array and by RT-qPCR. Results: A549 cells and EC displayed similar survival fraction and they had similar cell cycle distribution when irradiated alone or in co-culture. Both types of irradiation induced the overexpression of genes involved in cell growth, inflammation and angiogenesis. Conclusions: We set up new irradiation chamber in which two cell types were irradiated together with a particle beam. We could not show that tumor cells and endothelial cells were able to protect each other from particle irradiation. Gene expression changes were observed after particle irradiation that could suggest a possible radioprotective inter-cellular communication between the two cell types but further investigations are needed to confirm these results

  8. Effects of electron beam irradiation combined with hot water immersion treatment for shelf life extension of bananas

    International Nuclear Information System (INIS)

    A study of the effects of minimal processing treatments, both individually or in combinations, was carried out in order to extend the shelf life and to improve the quality of bananas. Pre climacteric bananas at light full three-quarter grade, were either treated with hot water immersion for 1-30 min at 45-55 degree C, or irradiated with electron beams (2.0 MeV, Van de Graaff accelerator), to a dose of 0.1-1.5 kGy. All fruit was stored at 21 ± 1 degree C and relative humidity of 85-95 %. There was no significant delay in ripening of fruit treated with hot water immersion at the above temperatures. Some damage to fruit particularly peel scalding at ends occurred at the higher temperatures (>50 degree C). The 50 degree C, 5 minutes immersion was selected for further study. Irradiation to 0.1-0.3 kGy delayed the ripening (up to 3 days) without affecting fruit quality. Doses greater than 0.4 kGy resulted in extensive discoloration and fruit splitting. No significant differences could be detected organoleptically between bananas irradiated at 0.15 kGy and the control. Results of the physico-chemical attributes of the bananas were reported for fruits at colour stage 5 and after 10 and 15 days of storage. The combination treatment of hot water immersion and irradiation at the above settings further extended the shelf life of the banana fruits

  9. Effects of electron beam irradiation on the photoelectrochemical properties of TiO2 film for DSSCs

    International Nuclear Information System (INIS)

    ABSTRACT: TiO2 has been widely utilized for various industrial applications such as photochemical cells, photocatalysts, and electrochromic devices. The crystallinity and morphology of TiO2 films play a significant role in determining the overall efficiency of dye-sensitized solar cells (DSSCs). In this study, the preparation of nanostructured TiO2 films by electron beam irradiation and their characterization were investigated for the application of DSSCs. TiO2 films were exposed to 20–100 kGy of electron beam irradiation using 1.14 MeV energy acceleration with a 7.46 mA beam current and 10 kGy/pass dose rates. These samples were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and X-ray photoelectron spectroscopy (XPS) analysis. After irradiation, each TiO2 film was tested as a DSSC. At low doses of electron beam irradiation (20 kGy), the energy conversion efficiency of the film was approximately 4.0% under illumination of simulated sunlight with AM 1.5 G (100 mW/cm2). We found that electron beam irradiation resulted in surface modification of the TiO2 films, which could explain the observed increase in the conversion efficiency in irradiated versus non-irradiated films. - Highlights: ► The surface of TiO2 particles was modified by electron beam irradiation. ► The aggregation between each TiO2 particle was observed in the SEM images. ► Ti3+ state was enhanced due to the excess electron injection via electron beam irradiation. ► The power conversion efficiency of DSSCs was enhanced.

  10. Effects of electron beam irradiation on the photoelectrochemical properties of TiO2 film for DSSCs

    Science.gov (United States)

    Kim, Hyun-Bin; Park, Dong-Won; Jeun, Joon-Pyo; Oh, Seung-Hwan; Nho, Young-Chang; Kang, Phil-Hyun

    2012-08-01

    iO2 has been widely utilized for various industrial applications such as photochemical cells, photocatalysts, and electrochromic devices. The crystallinity and morphology of TiO2 films play a significant role in determining the overall efficiency of dye-sensitized solar cells (DSSCs). In this study, the preparation of nanostructured TiO2 films by electron beam irradiation and their characterization were investigated for the application of DSSCs. TiO2 films were exposed to 20-100 kGy of electron beam irradiation using 1.14 MeV energy acceleration with a 7.46 mA beam current and 10 kGy/pass dose rates. These samples were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and X-ray photoelectron spectroscopy (XPS) analysis. After irradiation, each TiO2 film was tested as a DSSC. At low doses of electron beam irradiation (20 kGy), the energy conversion efficiency of the film was approximately 4.0% under illumination of simulated sunlight with AM 1.5 G (100 mW/cm2). We found that electron beam irradiation resulted in surface modification of the TiO2 films, which could explain the observed increase in the conversion efficiency in irradiated versus non-irradiated films.

  11. Investigation of electron beam irradiation effects on anti-nutritional factors, chemical composition and digestion kinetics of whole cottonseed, soybean and canola seeds

    Science.gov (United States)

    Ebrahimi-Mahmoudabad, S. R.; Taghinejad-Roudbaneh, M.

    2011-12-01

    This study was completed to determine effects of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on anti-nutritional factors, ruminal degradation and in vitro crude protein (CP) digestibility of whole cottonseed (WCS), soybean (SB) and canola seeds (CS). EB-irradiation eliminated completely ( Pphytic acid of WCS, SB and CS at a dose of 30 kGy. EB-irradiation decreased linearly ( P<0.001) the total glucosinolate content of CS. Trypsin inhibitor activity of 15, 30 and 45 kGy EB-irradiated SB was decreased by 19, 73 and 88%, respectively. Free gossypol content of WCS was reduced linearly ( P<0.001) by irradiation. EB-irradiation increased linearly ( P<0.001) CP digestibility of feeds. In conclusion, EB-irradiation was an effective processing method for improving the nutritive value of WCS, SB and CS.

  12. Effect of(12)C (+5) ion beam irradiation on cell viability and plant regeneration in callus, protoplasts and cell suspensions ofLavateva thuringiaca.

    Science.gov (United States)

    Vazquez-Tello, A; Uozumi, T; Hidaka, M; Kobayashi, Y; Watanabe, H

    1996-11-01

    The biological effects of irradiation with(12)C(+5) ion beam on plant cells have been analyzed. Protoplasts and cell suspensions ofLavatera thuringiaca, and a somatic hybrid callus (Hibiscus rosa-sinensis +Lavatera thuringiaca), were irradiated with doses from 0.05 to 50 Gy, and the effects on cell growth, cell division, cell viability and embryogenesis rates were analyzed. Irradiation with(12)C(+5) ion beam at relatively very low doses (5.0 Gy) significantly inhibited cell division, yet the survival rate and regeneration capability of the cells through somatic embryogenesis were conserved in more than 70 and 50 %, respectively. These results indicate that cell division is the most sensitive parameter to irradiation, accounting for the inhibition of colony formation and callus growth. The potential use of the(12)C(+5) ion beam in asymmetric protoplast fusion experiments is discussed. PMID:24178652

  13. Effect of antioxidants on thiobarbituric acid reactive substances, psychrotrophic bacteria and functional properties of mechanically deboned chicken meat irradiated with Cobalto-60 and electron beam sources

    International Nuclear Information System (INIS)

    Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 (Sodium Polyphosphate and Sodium Ascorbate and Antioxidant 2 (Rosemary Extract and α-Tocopherol. The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (C), with antioxidant A1 and non-irradiated (A1), with antioxidant A2 and non-irradiated (A2) without antioxidant and irradiated in Cobalt-60 source (Co), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). The samples was conditioned in a transparent, low density frozen overnight at a temperature of -18 ± 1 deg C in a chamber, and irradiated in this state with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy/h) and electron beam (7.86 kGy/s). After this process, the samples were evaluated during the refrigeration period (2 ± 1 deg C) for 11 days for the following analysis: total psychrotrophic bacteria count and thiobarbituric acid reactive substances (TBARS) and the analysis of functional properties were performed after the irradiation process. The use of the combination of rosemary antioxidant and α-tocopherol were able to significantly decrease TBARS values caused by the irradiation of samples in MDCM cobalt-60 sources and electron beam, and show a synergetic effect to processing with ionizing radiation to reduce of psychrotrophic bacteria count. The use of irradiation processing of MDCM did not negatively affect the functional properties studied. (author)

  14. Effect of antioxidants on thiobarbituric acid reactive substances, psychrotrophic bacteria and functional properties of mechanically deboned chicken meat irradiated with Cobalto-60 and electron beam sources

    Energy Technology Data Exchange (ETDEWEB)

    Brito, Poliana de Paula; Azevedo, Heliana de; Roque, Claudio Vitor; Pomarico Neto, Walter, E-mail: hgomes@cnen.gov.br, E-mail: pbrito@cnen.gov.br, E-mail: cvroque@cnen.gov.br, E-mail: abrusqui@cnen.gov.br [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas; Mourao, Gerson Barreto; Orlando, Eduardo Adilson; Miyagusku, Luciana, E-mail: marciamh@ital.sp.gov.br, E-mail: eduardo.orlando@ital.sp.gov.br [Instituto de Tecnologia dos Alimentos (ITAL), Campinas, SP (Brazil)

    2013-07-01

    Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 (Sodium Polyphosphate and Sodium Ascorbate and Antioxidant 2 (Rosemary Extract and α-Tocopherol. The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (C), with antioxidant A1 and non-irradiated (A1), with antioxidant A2 and non-irradiated (A2) without antioxidant and irradiated in Cobalt-60 source (Co), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). The samples was conditioned in a transparent, low density frozen overnight at a temperature of -18 ± 1 deg C in a chamber, and irradiated in this state with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy/h) and electron beam (7.86 kGy/s). After this process, the samples were evaluated during the refrigeration period (2 ± 1 deg C) for 11 days for the following analysis: total psychrotrophic bacteria count and thiobarbituric acid reactive substances (TBARS) and the analysis of functional properties were performed after the irradiation process. The use of the combination of rosemary antioxidant and α-tocopherol were able to significantly decrease TBARS values caused by the irradiation of samples in MDCM cobalt-60 sources and electron beam, and show a synergetic effect to processing with ionizing radiation to reduce of psychrotrophic bacteria count. The use of irradiation processing of MDCM did not negatively affect the functional properties studied. (author)

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

    International Nuclear Information System (INIS)

    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.)

  16. Recent progress in molecule modification with heavy ion beam irradiation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The research into heavy ion beam biology started in the 1960s, and so far it has become an important interdisciplinary study. Heavy ion beam is more suitable for molecule modification than other sorts of radiation, for it has many superiorities such as the energy transfer effect and the mass deposition effect. Molecule modification with heavy ion beam irradiation can be applied to developing new medicines and their precursors, genetic engineering, protein engi neering, outer space radiobiology, etc. Retrospect and prospect of the research and development of molecule modifica tion with heavy ion beam irradiation are given.

  17. The effect of a metal hip prosthesis on the radiation dose in therapeutic photon beam irradiations

    International Nuclear Information System (INIS)

    Prostate and cervical cancer patients are often treated with external X-ray beams of bi-lateral incidence. Such treatment may incur some dose effect that cannot be predicted precisely in commercial treatment planning systems (TPS) for patients having undergone total hip replacement. This study performs a Monte Carlo (MC) simulation and an analytical calculation (convolution superposition algorithm which is implemented in ADAC TPS) of a 6 MV, 5x5 cm2 X-ray beam incident into water with the existence of hip prosthesis, e.g. Ti6Al4V and CoCrMo alloy. The results indicate that ADAC TPS cannot precisely account for the scatter and backscatter radiation that a metal hip prosthesis causes. For percent depth dose (PDD) curves, the maximum underdosage of ADAC TPS up to 5 mm above the interface between dense material and water is 5%, 20% and 27% for PDDBone, PDDTi and PDDCo, respectively. The dose re-buildup, which occurs behind the hip region, becomes more and more obvious for denser medium existed in water. Increasing inhomogeneity also enhances the underdosage of ADAC for greater depth (>10 cm), as the figures of nearly 2% in PDDBone, PDDTi and 4-5% in PDDCo reveal. Overestimating the attenuated power of high-density non-water material in ADAC TPS causes this underdosage. For dose profiles, no significant differences were found in ProfileBone at any depth. ProfileTi reveals that MC slightly exceeds ADAC at off-axis position 1.0-2.0 cm. ProfileCo reveals this more obviously. This finding means that scatter radiation from these denser materials is significant and cannot be predicted precisely in ADAC

  18. Search for the effect of E-beam irradiation on some steroids

    Energy Technology Data Exchange (ETDEWEB)

    Marciniec, B. E-mail: bmarcin@amp.edu.pl; Ogrodowczyk, M.; Dettlaff, K

    2005-03-01

    Seven steroid derivatives (hydrocortisone, hydrocortisone acetate, prednisolone, prednisolone acetate, methylprednisolone acetate, dexamethasone and fludrocortisone acetate) irradiated in the solid phase 10 MeV electrons, were studied by chromatographic methods (TLC and HPLC). Before the irradiation the derivatives contained different amounts of the following impurities: cortisone, cortisone acetate, prednisolone, prednisolone acetate and prednisone. After irradiation with a dose of upto 200 kGy radiolytic products were identified: cortisone, cortisone acetate, prednisone, prednisolone and methylprednisone acetate. All the identified radiolytic products were formed as a result of oxidation of the substituent at C{sub 11}, and in some cases the oxidation was accompanied by cleavage of the ester bond. The content of impurities before irradiation did not exceed 0.8%, while after the irradiation the content of the products of radiolysis depended on the kind of the derivative and the dose, and varied from 0.6% for a dose of 25 kGy to 4.03% for a dose of 200 kGy. For some derivatives, a linear relationship was found between the loss of a given steroid content and the dose. The studied steroid derivatives are characterised by high radiochemical stability and their sterilisation by irradiation does not lead to loss of the active substance below 97%, i.e. the lower limit admissible by the pharmacopoeias.

  19. Search for the effect of E-beam irradiation on some steroids

    Science.gov (United States)

    Marciniec, B.; Ogrodowczyk, M.; Dettlaff, K.

    2005-03-01

    Seven steroid derivatives (hydrocortisone, hydrocortisone acetate, prednisolone, prednisolone acetate, methylprednisolone acetate, dexamethasone and fludrocortisone acetate) irradiated in the solid phase 10 MeV electrons, were studied by chromatographic methods (TLC and HPLC). Before the irradiation the derivatives contained different amounts of the following impurities: cortisone, cortisone acetate, prednisolone, prednisolone acetate and prednisone. After irradiation with a dose of upto 200 kGy radiolytic products were identified: cortisone, cortisone acetate, prednisone, prednisolone and methylprednisone acetate. All the identified radiolytic products were formed as a result of oxidation of the substituent at C 11, and in some cases the oxidation was accompanied by cleavage of the ester bond. The content of impurities before irradiation did not exceed 0.8%, while after the irradiation the content of the products of radiolysis depended on the kind of the derivative and the dose, and varied from 0.6% for a dose of 25 kGy to 4.03% for a dose of 200 kGy. For some derivatives, a linear relationship was found between the loss of a given steroid content and the dose. The studied steroid derivatives are characterised by high radiochemical stability and their sterilisation by irradiation does not lead to loss of the active substance below 97%, i.e. the lower limit admissible by the pharmacopoeias.

  20. Surface finish of micro punch with ion beam irradiation

    Institute of Scientific and Technical Information of China (English)

    XU Jie; WANG Chun-ju; GUO Bin; SHAN De-bin; Y.SUGIYAMA; S.ONO

    2009-01-01

    Ion beam irradiation was adopted for surface treatment of the micro punch manufactured by precision machining. Ar plasma was used for the ion irradiation process, which was generated by the electron cyclotron resonance(ECR) equipment. The surface finish processes of micro punch were carried out at irradiation angles of 45°and 10°, respectively. The surface roughness and topography were measured to estimate the quality of surface finish. The results show that the ion irradiation is very effective to reduce the surface roughness, which can be improved more significantly at irradiation angle of 10°than at 45°. The technology of surface finish with ion beam irradiation is suitable for the surface treatment of micro die.

  1. Radical formation of irradiated α-alanine and N-acetyl alanine with heavy ion beams. Effects of the irradiation temperature

    International Nuclear Information System (INIS)

    The characteristics of irradiation with C290 MeV/u ion beams were investigated using X-band electron spin resonance (ESR) spectroscopy for a polycrystalline powder of L-α-alanine at from 77K to 310K. The formed main radicals at 190K∼310K were the deamino radical and the decarboxyl radical. Because of the first-derivative ESR, decarboxyl radical showed an expanded spectral width and a lower peak height because of its amino hydrogen and nitrogen than that of the same amount of deamino radical. The ESR of irradiated L-α-alanine predominantly indicates the spectrum of the deamino radical. On the irradiated, L-α-alanine at from 77K to 310K ESR showed 1:4:6:4:1 lines at 220K and at room temperature, which indicate that the methyl group of the radical was rotating. On the other hand, at 77K ESR the spectrum showed nearly 1:5:5:5:1 lines, like the teeth of a saw, on samples irradiated at 270K∼350K (range IV), and 1:4:6:4:1 lines for those irradiated at 180K∼260K (range II and III), respectively. It is considered that the radical conformation of the deamino radical is planar (most stable conformation) on an irradiated sample in range IV, and a pyramidal structure on the irradiated sample in ranges II and III. (author)

  2. Study of electron beam irradiation effects on morphologic properties of the PET/PP/PE/EVA polymeric blend

    Energy Technology Data Exchange (ETDEWEB)

    Rossini, Edvaldo L.; Silva, Leonardo G. Andrade e, E-mail: lgasilva@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Wiebeck, Helio, E-mail: hwiebeck@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica

    2009-07-01

    Amidst the pollutants, plastics and especially the 'PET bottles' packaging type, which comprise of poly(ethylene terephthalate) (PET), polypropylene (PP), polyethylene (PE) and poly[ethylene-co-(vinyl acetate)] (EVA) have been causing big damage to the environment. In this work, the polymeric blend PET/PP/PE/EVA was obtained by mechanical recycling 'PET bottles' after consumption, with the objective of finding a solution for this environmental problem. It was also studied the different ionizing radiation dose effects (25, 50, 75, 100, 150, 200, 300, 400 and 500 kGy) on the blend properties using an electron beam accelerator. The morphologic properties of the non-irradiated and irradiated polymeric blend were evaluated by the Light Microscopy (LM) and Scanning Electron Microscopy (SEM). The analysis of the results appeared to be a not mixing and compatible blend. The use of the ionizing radiation improved the homogeneity of the blend. These modifications have been randomized and irregular, depending directly on the dose of applied radiation. (author)

  3. Bony regeneration effect of electron-beam irradiated hydroxyapatite and tricalcium phosphate mixtures with 7 to 3 ratio in the caravel defect model of rat

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soung Min; Eo, Mi Young; Kang, Ji Young; Myoung, Hoon; Lee, Jong Ho [Seoul National Univ., Seoul (Korea, Republic of); Cho, Hye Jin [Korea Basic Science Institute, Daejeon (Korea, Republic of); Yea, Kwon Hae; Lee, Byung Cheol [Korea Atomic Research Institute, Daejeon (Korea, Republic of)

    2011-07-01

    The aim of this study is to evaluate the effect and potential of electron beam irradiation treatment to the new bone formation in the rat calvarial bony defects by using of 7 to 3 ratios of hydroxyapatite and tricalcium phosphate mixed with type I collagen. We used 1.0 MeV linear accelerator and 2.0 MeV superconductive linear accelerator with different irradiation dose, such as 1, 30, 60 kGy. And 10.0 MeV high frequency superconductive linear accelerator was also used. In six different experimental groups, the defect of every three rate was filled with E-beam irradiated bony mixtures, which different energy and dose, and that of rats without E-beam irradiated bony mixtures can be compared with out previous results. The other three rats were used as sham group. Rats were sacrificed after 4, 8, and 16 weeks, and grafted healing specimens were studied by clinical and radiographic findings, histomorphologic staining with hematoxylin and eosin. The large particular size of HLA was changed to small particles after E-beam irradiation, to which small particle of TEPC was engaged to small sexed HLA with organic collagen components in Seam findings. Abundant endothelial cells with preciosity were found around inner portions of grafted healing bone and many couplings of osteoblast with osteoclast in Tem findings were found in every experimental groups.

  4. The effect of high-energy electron-beam irradiation on microstructural modification of a high-speed steel roll

    International Nuclear Information System (INIS)

    The purpose of this study is to investigate the microstructural modification in a high-speed steel (HSS) roll irradiated with an accelerated high-energy electron beam. The HSS roll samples were irradiated at the beam travel speeds of 2.5 to 25 mm/s using an electron accelerator (1.4 MeV). The microstructure was examined with a scanning electron microscope (SEM) capable of in situ fracture testing and simultaneous measurement of the apparent fracture toughness. Irradiation changed the matrix phase from tempered martensite to a mixture of retained austenite and martensite. Coarse primary carbides were partially or completely dissolved, depending on the heat input. Irradiation greatly improved the fracture properties because of the presence of retained austenite, which could retard crack propagation, although hardness was decreased. Occasional interior quench cracks were found in the heat-affected region. Appropriate processing methods, such as pre- or postirradiation, were suggested. A heat transfer analysis of the irradiated surface layer was also carried out to elucidate the influence of the irradiation parameters on the microstructure

  5. Effect of electron beam irradiation on polymer electrolytes: Change in morphology, crystallinity, dielectric constant and AC conductivity with dose

    International Nuclear Information System (INIS)

    Polymer electrolyte (PEO:Li2SO4) films were exposed to 8 MeV electron beam (EB) with various doses to investigate the radiation effect on dielectric permittivity (real and imaginary) and AC conductivity by using PC based Impedance Analyzer in the frequency range of 40–1 MHz at different temperatures. The change in chemical interaction, morphology, and thermal properties was analyzed with the help of Fourier Transform InfraRed (FT-IR), Scanning Electron Micrographs (SEM) and Differential Scanning Calorimeter (DSC) techniques respectively for before and after irradiation. The chemical change was confirmed from the FT-IR result which showed that peak intensities corresponding to C–H, C=C, and –C–O–C– bonds decrease with increase in EB dose clearly indicating that the degradation of polymer chain or segments (i.e., –CH2–CH2–). The DSC result showed that the melting temperature of unirradiated film is 69.42 °C which reduced to 67.55 °C for 30 kGy dose suggesting an exothermic behaviour. The SEM images give that surface roughness and crack depths increase with increasing dose. The XRD result reveals a decreased ∼30% crystallite size for 30 kGy dose compared with unirradiated film. Further, it is seen that dielectric permittivity and frequency dependent conductivity were found to increase with increasing irradiation dose. The maximum AC conductivity was observed to be 1.88×10−4 s/cm for 30 kGy and the estimated change in charge carrier concentration also showed high for 30 kGy dose. The AC conductivity obeys Power's law. The frequency exponent (s) parameter shows temperature dependent behaviour which decreases after irradiation. - Highlights: • 8 MeV EB irradiation effect on dielectric constant and AC conductivity of polymer electrolyte films was observed. • Occurrence of chain scission due to breaking of bonds was confirmed by FT-IR analysis. • AC conductivity increases with dose due to more number of free charges involved in

  6. Effects of temperature, packaging and electron beam irradiation processing conditions on the property behaviour of Poly (ether-block-amide) blends

    International Nuclear Information System (INIS)

    The radiation stability of Poly (ether-block-amide) (PEBA) blended with a multifunctional phenolic antioxidant and a hindered amide light stabiliser was examined under various temperatures, packaging and electron beam processing conditions. FTIR revealed that there were slight alterations to the PEBA before irradiation; however, these became more pronounced following irradiation. The effect of varying the temperature, packaging and processing conditions on the resultant PEBA properties was apparent. For example, rheology demonstrated that the structural properties could be enhanced by manipulating the aforementioned criteria. Mechanical testing exhibited less radiation resistance when the PEBA samples were vacuum packed and exposed to irradiation. MFI and AFM confirmed that the melting strength and surface topography could be reduced/increased depending on the conditions employed. From this study it was concluded that virgin PEBA submerged in dry ice with non-vacuum packaging during the irradiation process, provided excellent radiation resistance (20.9% improvement) in contrast to the traditional method. - Highlights: • PEBA was melt blended with Irganox 565 and Tinuvin 783. • All virgin and blended PEBA samples were exposed to electron beam irradiation. • Virgin and blended PEBA was exposed to different temperatures during irradiation. • Non-vacuum and vacuum packed PEBA samples were compared following irradiation. • Virgin PEBA with non-vacuum packaging in dry ice improved the radiation resistance

  7. A systematic study on the effect of electron beam irradiation on structural, electrical, thermo-electric power and magnetic property of LaCoO3

    Science.gov (United States)

    Benedict, Christopher J.; Rao, Ashok; Sanjeev, Ganesh; Okram, G. S.; Babu, P. D.

    2016-01-01

    In this communication, the effect of electron beam irradiation on the structural, electrical, thermo-electric power and magnetic properties of LaCoO3 cobaltites have been investigated. Rietveld refinement of XRD data reveals that all samples are single phased with rhombohedral structure. Increase in electrical resistivity data is observed with increase in dosage of electron beam irradiation. Analysis of the measured electrical resistivity data indicates that the small polaron hopping model is operative in the high temperature regime for all samples. The Seebeck coefficient (S) of the pristine and the irradiated samples exhibits a crossover from positive to negative values, and a colossal value of Seebeck coefficient (32.65 mV/K) is obtained for pristine sample, however, the value of S decreases with increase in dosage of irradiation. The analysis of Seebeck coefficient data confirms that the small polaron hopping model is operative in the high temperature region. The magnetization results give clear evidence of increase in effective magnetic moment due to increase in dosage of electron beam irradiation.

  8. Waste treatment by microwave and electron beam irradiation

    International Nuclear Information System (INIS)

    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

  9. Evaluation of the effects of electron-beam irradiation on the puncture resistance by Lasioderma serricorne in flexible packaging of granola

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Vitor M.; Alves, Juliana N.; Nogueira, Beatriz R.; Moura, Esperidiana A.B., E-mail: vmiranda@ipen.b, E-mail: julianaabc@ig.com.b, E-mail: bia.ribnog@gmail.co, E-mail: eabmoura@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Ortiz, Angel V., E-mail: angel.ortiz@unipacnet.com.b [UNIPAC Embalagens Ltda., Sao Paulo, SP (Brazil); Potenza, Marcos R., E-mail: potenza@biologico.sp.gov.b [Instituto Biologico de Sao Paulo/APTA, Sao Paulo, SP (Brazil)

    2009-07-01

    Lasioderma serricorne is a beetle that infests stored and industrialized dry foods such as cereal bars, granola, flour and pasta, amongst others, depreciating the products and causing economic losses. It is therefore critical for these products a packaging that presents, in addition to good mechanical, barrier and machinability properties, a good resistance to puncture by insects, in order to prevent the contact and spread of pests in the packaged food. This study evaluates the changes on mechanical properties and puncture resistance by L. serricorne in BOPP/PP structure, used commercially as granola packaging after electron-beam irradiation. The irradiations were performed using a 1.5 MeV electron beam accelerator, dose rate of 11.22 kGy/s, at room temperature in presence of air, doses up to 120 kGy. After irradiation the BOPP/PP samples were subjected to tests of puncture resistance by L. serricorne, tensile strength, friction coefficient, penetration and seal strength. Results showed decreases in the original mechanical properties of the structure according to the radiation doses applied and effective resistance against punctures by L. serricorne (p<0.05). The results indicate that the irradiated and non-irradiated BOPP/PP structure, in the conditions studied in this work, is resistant against L. serricorne, however the decreases observed in the mechanical properties of the irradiated structure may turn it inappropriate for packaging granola. (author)

  10. Microbial quality evaluation and effective decontamination of nutraceutically valued lotus seeds by electron beams and gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Rajeev, E-mail: rajeevbhat1304@gmail.co [Food Technology Division, School of Industrial Technology, Universiti Sains Malaysia, Penang 11800 (Malaysia); Sridhar, K.R. [Microbiology and Biotechnology, Department of Biosciences, Mangalore University, Mangalagangotri, Mangalore 574199, Karnataka (India); Karim, A.A. [Food Technology Division, School of Industrial Technology, Universiti Sains Malaysia, Penang 11800 (Malaysia)

    2010-09-15

    Lotus seeds are nutraceutically valued natural plant produce, which succumbs to microbial contamination, predominantly to toxigenic moulds. Results of the present study revealed seed coat portion to harbor higher proportion of microbial load, particularly fungi than cotyledon portion. Among the mycotoxins analyzed, aflatoxins (B{sub 1}, B{sub 2}, G{sub 1} and G{sub 2}) were below detectable limits, while the seeds were devoid of Ochratoxin-A (OTA). Application of different doses of electron beam and gamma irradiation (0, 2.5, 5, 7.5, 10, 15 and 30 kGy) for decontamination purpose revealed significant dose-dependent decrease in the fungal contaminants (P<0.05). However, the contaminant yeasts could survive up to 10 kGy dose, which could be completely eliminated at 15 kGy. From the results obtained, a dose range between 10 and 15 kGy is recommended for complete decontamination, as these doses have also been shown earlier to have minimal effects on nutritional and functional properties of lotus seeds.

  11. Microbial quality evaluation and effective decontamination of nutraceutically valued lotus seeds by electron beams and gamma irradiation

    International Nuclear Information System (INIS)

    Lotus seeds are nutraceutically valued natural plant produce, which succumbs to microbial contamination, predominantly to toxigenic moulds. Results of the present study revealed seed coat portion to harbor higher proportion of microbial load, particularly fungi than cotyledon portion. Among the mycotoxins analyzed, aflatoxins (B1, B2, G1 and G2) were below detectable limits, while the seeds were devoid of Ochratoxin-A (OTA). Application of different doses of electron beam and gamma irradiation (0, 2.5, 5, 7.5, 10, 15 and 30 kGy) for decontamination purpose revealed significant dose-dependent decrease in the fungal contaminants (P<0.05). However, the contaminant yeasts could survive up to 10 kGy dose, which could be completely eliminated at 15 kGy. From the results obtained, a dose range between 10 and 15 kGy is recommended for complete decontamination, as these doses have also been shown earlier to have minimal effects on nutritional and functional properties of lotus seeds.

  12. Effect of oxidant addition on the elimination of 2-naphthalenesulfonate in aqueous solutions by electron beam irradiation

    Science.gov (United States)

    Alkhuraiji, Turki S.; Karpel Vel Leitner, Nathalie

    2016-09-01

    Aromatic sulfonated compounds and naphthalene derivatives are major chemical compounds used in the industry. Electron beam irradiation of aqueous solutions of 2-naphthalenesulfonate (90 μM) was investigated under various experimental conditions. The results obtained demonstrate that the 2-NS concentration decreased dramatically on increasing the absorbed dose in the range 0-1000 Gy. The effectiveness of the radiolytic system was demonstrably enhanced by the addition of oxidants (S2O82- or H2O2). 2-NS removal was higher with S2O82- than with H2O2. For the EB, EB/H2O2, and EB/S2O82- systems, the absorbed doses for 90% elimination of 2-NS (D90) were 700, 480, and 274 Gy, respectively. 2-NS is poorly mineralized by EB but more than 35% mineralization was reached for 15 kGy when oxidants (820 μM S2O82- or 935 μM H2O2) were added. In all systems, the mineralization yield was markedly higher when air (i.e. dissolved oxygen increase) was introduced between successive doses. For 50% 2-NS removal, seven sulfonated transformation products were identified using LC/MS analyses. For the highest absorbed doses the sulfonate group in 2-NS was converted to sulfate ions in the radiolytic systems.

  13. Effect of water and oxygen contents on the decomposition of gaseous trichloroethylene in air under electron beam irradiation

    International Nuclear Information System (INIS)

    An electron beam (EB) treatment of gaseous trichloroethylene (TCE) in air was studied as a purification method of off-gases containing gaseous chloroethylenes. The model air containing TCE at input concentrations of 5-75 ppmv, detected mostly in actual off-gases, was irradiated with 1-MeV EBs in a gas-flow vessel at 10 L/min under the conditions of atmospheric pressure, 298 K, and different H2O contents. The decomposition of 75 ppmv TCE was also examined in humid air under different O2 contents of 1x103 - 2.1x105 ppmv. In the existence of H2O and O2 contents with ≥ 3x102 ppmv and ≥ 5x103 ppmv, respectively, the decomposition ratios of TCE were enhanced and TCE was decomposed into 83.0±1.5% of dichloroacetyl chloride (DCAC) and 17.5±0.6% of carbonyl chloride (COCl2) independently of the input TCE concentrations based on the carbon balance. Trichloroethylene of 5-75 ppmv was effectively decomposed by the OH radical through Cl-radical chain oxidation under the above-mentioned air conditions. (author)

  14. Microbial quality evaluation and effective decontamination of nutraceutically valued lotus seeds by electron beams and gamma irradiation

    Science.gov (United States)

    Bhat, Rajeev; Sridhar, K. R.; Karim, A. A.

    2010-09-01

    Lotus seeds are nutraceutically valued natural plant produce, which succumbs to microbial contamination, predominantly to toxigenic moulds. Results of the present study revealed seed coat portion to harbor higher proportion of microbial load, particularly fungi than cotyledon portion. Among the mycotoxins analyzed, aflatoxins (B 1, B 2, G 1 and G 2) were below detectable limits, while the seeds were devoid of Ochratoxin-A (OTA). Application of different doses of electron beam and gamma irradiation (0, 2.5, 5, 7.5, 10, 15 and 30 kGy) for decontamination purpose revealed significant dose-dependent decrease in the fungal contaminants ( P<0.05). However, the contaminant yeasts could survive up to 10 kGy dose, which could be completely eliminated at 15 kGy. From the results obtained, a dose range between 10 and 15 kGy is recommended for complete decontamination, as these doses have also been shown earlier to have minimal effects on nutritional and functional properties of lotus seeds.

  15. Dose Response of Alanine Detectors Irradiated with Carbon Ion Beams

    DEFF Research Database (Denmark)

    Herrmann, Rochus; Jäkel, Oliver; Palmans, Hugo;

    2011-01-01

    . Methods: Alanine detectors have been irradiated with carbon ions with an energy range of 89-400 MeV/u. The relative effectiveness of alanine has been measured in this regime. Pristine and spread out Bragg peak depth-dose curves have been measured with alanine dosimeters. The track-structure based alanine......Purpose: The dose response of the alanine detector shows a dependence on particle energy and type, when irradiated with ion beams. The purpose of this study is to investigate the response behaviour of the alanine detector in clinical carbon ion beams and compare the results with model predictions...... of the detector geometry implemented in the Monte Carlo simulations....

  16. The effect of electron beam irradiation on the mechanical properties of pineapple leaf fibre (PALF) reinforced high impact polystyrene (HIPS) composites

    Energy Technology Data Exchange (ETDEWEB)

    Siregar, J P; Sapuan, S M [Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Rahman, M Z A [Department of Chemistry, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Zaman, H M D K, E-mail: januarjasmine@yahoo.com [Radiation Processing Technology Division, Malaysia Nuclear Agency, Bangi 43000 Kajang, Selangor (Malaysia)

    2010-05-15

    The effects of electron beam irradiation on the mechanical properties of pineapple leaf fibre reinforced high impact polystyrene (HIPS) composites were studied. Two types of crosslinking agent that has been used in this study were trimethylolpropane triacrylate (TMPTA) and tripropylene gylcol diacrylate (TPGDA). A 50 wt.% of PALF was blended with HIPS and crosslinking agent using Brabender melt mixer at 165 deg. C. The composites were then irradiated using a 3 MeV electron beam accelerator with dosage of 0-100 kGy. The tensile strength, tensile modulus, flexural strength, flexural modulus, notched and unnotched impat and hardness of composites were measured and the effects of crosslinking agent were also compared.

  17. The effect of electron beam irradiation on the mechanical properties of pineapple leaf fibre (PALF) reinforced high impact polystyrene (HIPS) composites

    Science.gov (United States)

    Siregar, J. P.; Sapuan, S. M.; Rahman, M. Z. A.; Zaman, H. M. D. K.

    2010-05-01

    The effects of electron beam irradiation on the mechanical properties of pineapple leaf fibre reinforced high impact polystyrene (HIPS) composites were studied. Two types of crosslinking agent that has been used in this study were trimethylolpropane triacrylate (TMPTA) and tripropylene gylcol diacrylate (TPGDA). A 50 wt.% of PALF was blended with HIPS and crosslinking agent using Brabender melt mixer at 165 °C. The composites were then irradiated using a 3 MeV electron beam accelerator with dosage of 0-100 kGy. The tensile strength, tensile modulus, flexural strength, flexural modulus, notched and unnotched impat and hardness of composites were measured and the effects of crosslinking agent were also compared.

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

    International Nuclear Information System (INIS)

    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

  19. Effects of electrical characteristics of InGaP solar cell on low energy electron beam irradiation

    International Nuclear Information System (INIS)

    The solar cell used for a satellite has commonly triple-junction, whose top-subcell is made of InGaP. The electrons can recoil the atoms in the crystal lattice of the cells at energies above the threshold energies. Theoretically obtained threshold energies for recoil atoms of the InGaP cell by an electron are about 120 - 320 keV. The research using low energy electron beams is important to investigate the mechanism of the degradation of the cell by the defects. The InGaP solar cell was irradiated with electron beams by the Cockcroft Walton electron accelerator in a vacuum and at an ambient temperature. The energies and the fluences of the electron beams are from 60 to 500 keV and from 3 × 1014 to 3 × 1016 cm-2. Degradation of the open-circuit voltage of solar cell energy at less than 100 keV was observed. This degradation was not predicted on the theory. This result suggests that defects were caused by not only the recoil but also the absorbed dose by electron. At an electron energy of more than 400 keV the RF of the short-circuit current (Isc) has been found to increase at a fluence below about 3 × 1014. For the higher fluence the RF of Isc has gradually decreased. This phenomenon can be attributed to the increase of carrier concentration due to the irradiation. (author)

  20. Protective effects of melatonin against 12C6+ beam irradiation-induced oxidative stress and DNA injury in the mouse brain

    Science.gov (United States)

    Wu, Z. H.; Zhang, H.; Wang, X. Y.; Yang, R.; Liu, B.; Liu, Y.; Zhao, W. P.; Feng, H. Y.; Xue, L. G.; Hao, J. F.; Niu, B. T.; Wang, Z. H.

    2012-01-01

    The purpose of this experiment was to estimate the protective effects of melatonin against radiation-induced brain damages in mice induced by heavy ion beams. Kun-Ming mice were randomly divided into five groups: normal control group, irradiation control group, and three different doses of melatonin (5, 10, and 20 mg/kg, i.p.) treated groups. Apart from the normal control group, the other four groups were exposed to whole-body 4.0 Gy carbon ion beam irradiation (approximately 0.5 Gy/min) after i.p. administration of normal saline or melatonin 1 h before irradiation. The oxidative redox status of brain tissue was assessed by measurement of malondiadehyde (MDA) levels, total superoxide dismutase (T-SOD), cytosolic superoxide dismutase (Cu/ZnSOD, SOD1) and mitochondrial superoxide dismutase (MnSOD, SOD2) activities at 8 h after irradiation. DNA damages were determined using the Comet assay and apoptosis and cell cycle distribution were detected by flow cytometric analyses. A dramatic dose-dependent decrease in MDA levels, tail moment, rates of tailing cells, and apoptosis, and a dose-dependent increase in T-SOD and SOD2 activities, in brain tissues in the melatonin-treated groups were detected compared with the irradiation only group. Furthermore, flow cytometric analysis demonstrated that the percentage of brain cells in the G0/G1 phase decreased significantly, while those in the S and G2/M stage increased dramatically, with mice pretreated with melatonin compared to the irradiation control group. These data indicate that melatonin has protective effects against irradiation-induced brain injury, and that its underlying protective mechanisms may relate to modulation of oxidative stress induced by heavy ionirradiation.

  1. Total body irradiation with a sweeping beam

    Energy Technology Data Exchange (ETDEWEB)

    Pla, M.; Chenery, S.G.; Podgorsak, E.B.

    1983-01-01

    A technique for total body irradiation, in which the patient lies in the prone or supine position in the beam of a conventional column mounted 4 MV linear accelerator, is described. A sufficiently large radiation field is obtained by rotating the beam in a vertical plane about the source (i.e., sweeping beam) at a source-to-skin distance of 190 cm on the vertical axis. The variation of the midplane dose is less than +lt. slash-5% in parallel-opposed beams, when attenuators are placed over the region containing the lungs and bolus is employed around the head and legs. The percentage depth dose for the sweeping beam is identical to that of a stationary beam for the same collimator setting and source-to-skin distance. A method for monitoring the dose to the patient by means of a thimble ionization chamber located on the vertical beam axis is outlined. The average dose rates used are between 5 and 10 cGy/min. The design and placement of lung attenuators is simple. The treatment technique with the sweeping beam requires minimal modification of a treatment unit and can be applied on any unit which has a head swivel option.

  2. Irradiation application of electronic beam accelerator NBL-1010

    International Nuclear Information System (INIS)

    The application of electronic beam accelerator NBL-1010 in semiconductor denature, gem coloring, waster treatment, chemical synthesize of radiation, degrading of agricultural waster, sterilization of one-off medical treatment, sterilization of herbs, food preservation, crystal coloring and preservation of commodities was studied for its effects equaled with cobalt gamma irradiation

  3. Exhaust gas treatment by electron beam irradiation

    International Nuclear Information System (INIS)

    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.)

  4. The effects of electron beam irradiation on the thermal properties, fatigue life and natural weathering of styrene butadiene rubber/recycled acrylonitrile-butadiene rubber blends

    International Nuclear Information System (INIS)

    Research highlights: → Addition of TMPTA helps to align polymer chains through crosslinking. → Improvement in fatigue life of irradiated blends due to formation of irradiation-induced crosslinks. → Excessive crosslinking caused reduction of tensile properties of irradiated SBR/NBRr blends. -- Abstract: The effects of electron beam (EB) irradiation on the thermal properties, fatigue life and natural weathering of styrene butadiene rubber/recycled acrylonitrile-butadiene rubber (SBR/NBRr) blends were investigated. The SBR/NBRr blends were prepared at 95/5, 85/15, 75/25, 65/35, or 50/50 blend ratios with and without the presence of a 3 part per hundred rubber (phr) of polyfunctional monomer, trimethylolpropane triacrylate (TMPTA). Results indicate that the crystallisation temperature (Tc) observed in polymeric blends is due to the alignment of polymer chains forming a semi-crystalline phase. Addition of TMPTA helps to align polymer chains through crosslinking. More crosslinking occurred between polymer blends with the help of TMPTA, upon irradiation. The improvement in fatigue life can also be associated with the stabilisation of SBR/NBRr blends upon irradiation and irradiation-induced crosslinking, which was accomplished with relatively low radiation-induced oxidative degradation in the presence of TMPTA. The tensile properties of both blends decreased over the periods of environmental exposure due to the effect of polymer degradation. After 6 months, the irradiated SBR/NBRr blends could not retain better retention [mainly with 25, 35 or 50 phr of recycled acrylonitrile-butadiene rubber (NBRr) particles] due to the samples becoming brittle over the long period of outdoor exposure.

  5. Temperature measurements during high flux ion beam irradiations.

    Science.gov (United States)

    Crespillo, M L; Graham, J T; Zhang, Y; Weber, W J

    2016-02-01

    A systematic study of the ion beam heating effect was performed in a temperature range of -170 to 900 °C using a 10 MeV Au(3+) ion beam and a Yttria stabilized Zirconia (YSZ) sample at a flux of 5.5 × 10(12) cm(-2) s(-1). Different geometric configurations of beam, sample, thermocouple positioning, and sample holder were compared to understand the heat/charge transport mechanisms responsible for the observed temperature increase. The beam heating exhibited a strong dependence on the background (initial) sample temperature with the largest temperature increases occurring at cryogenic temperatures and decreasing with increasing temperature. Comparison with numerical calculations suggests that the observed heating effect is, in reality, a predominantly electronic effect and the true temperature rise is small. A simple model was developed to explain this electronic effect in terms of an electrostatic potential that forms during ion irradiation. Such an artificial beam heating effect is potentially problematic in thermostated ion irradiation and ion beam analysis apparatus, as the operation of temperature feedback systems can be significantly distorted by this effect. PMID:26931879

  6. Effects of E-Beam Irradiation on the Chemical, Physical, and Electrochemical Properties of Activated Carbons for Electric Double-Layer Capacitors

    OpenAIRE

    Min-Jung Jung; Mi-Seon Park; Young-Seak Lee

    2015-01-01

    Activated carbons (ACs) were modified via e-beam irradiation at various doses for use as an electrode material in electric double-layer capacitors (EDLCs). The chemical compositions of the AC surfaces were largely unchanged by the e-beam irradiation. The ACs treated with the e-beam at radiation doses of 200 kGy exhibited higher nanocrystallinity than the untreated ACs. The specific surface areas and pore volumes of the e-beam irradiated ACs were also higher than those of the untreated ACs. Th...

  7. Electron-Beam Irradiation Effect on Thermal and Mechanical Properties of Nylon-6 Nanocomposite Fibers Infused with Diamond and Diamond Coated Carbon Nanotubes

    Science.gov (United States)

    Imam, Muhammad A.; Jeelani, Shaik; Rangari, Vijaya K.; Gome, Michelle G.; Moura, Esperidiana. A. B.

    2016-02-01

    Nylon-6 is an engineering plastic with excellent properties and processability, which are essential in several industrial applications. The addition of filler such as diamond (DN) and diamond coated carbon nanotubes (CNTs) to form molded composites may increase the range of Nylon-6 applications due to the resulting increase in strength. The effects of electron-beam irradiation on these thermoplastic nanocomposites are either increase in the cross-linking or causes chain scission. In this study, DN-coated CNTs were synthesized using the sonochemical technique in the presence of cationic surfactant cetyltrimethyl ammonium bromide (CTAB). The DN-coated CNTs nanoparticles and diamond nanoparticles were then introduced into Nylon-6 polymer through a melt extrusion process to form nanocomposite fibers. They were further tested for their mechanical (Tensile) and thermal properties (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC)). These composites were further exposed to the electron-beam (160kGy, 132kGy and 99kGy) irradiation using a 1.5MeV electron-beam accelerator, at room temperature, in the presence of air and tested for their thermal and mechanical properties. The best ultimate tensile strength was found to be 690MPa and 864MPa irradiated at 132 for DN/CNTs/Nylon-6 and Diamond/Nylon-6 nanocomposite fiber as compared to 346MPa and 321MPa for DN/CNTs/Nylon-6 and Diamond/Nylon-6 nanocomposite fiber without irradiation. The neat Nylon-6 tensile strength was 240MPa. These results are consistent with the activation energy calculated from TGA graphs. DSC analysis result shows that the slight increase in glass transition temperature (Tg) and decrease in melting temperature (Tm) which was expected from high electron-beam radiation dose.

  8. 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).

  9. Effects of co-implanted oxygen or aluminum atoms on hydrogen migration and damage structure in multiple-beam irradiated Al sub 2 O sub 3

    CERN Document Server

    Katano, Y; Yamamoto, S; Nakazawa, T; Yamaki, D; Noda, K

    2000-01-01

    Depth profiles of implanted H atoms were measured for single crystalline Al sub 2 O sub 3 samples irradiated at 923 K with dual or triple beams of 0.25 MeV H-, 0.6 MeV He-, 2.4 MeV O-ions or 2.6 MeV Al-ions. The peaks occur at 1.55 and 1.45 mu m in the depth profiles measured for the H + Al dual beam irradiation and H + O dual beam case, respectively. The ratio of the peak areas is over 4, which is much larger than the implanted H atom ratio of 1.1, indicating that implanted Al atoms suppress the mobility of H atoms. However, the ratio becomes almost 1 between the triple beam samples with H + He + O-ions and with H + He + Al-ions at comparable doses. The fact demonstrates that implanted He atoms overwhelm the effects of the implanted self-cation/anion excess atoms on the migration behaviors of implanted hydrogen and radiation produced point defects, with the resulting sluggish cavity growth observed.

  10. Effects of prenatal irradiation with accelerated heavy-ion beams on postnatal development in rats: III. Testicular development and breeding activity

    Science.gov (United States)

    Wang, B.; Murakami, M.; Eguchi-Kasai, K.; Nojima, K.; Shang, Y.; Tanaka, K.; Watanabe, K.; Fujita, K.; Moreno, S. G.; Coffigny, H.; Hayata, I.

    With a significant increase in human activities dealing with space missions, potential teratogenic effects on the mammalian reproductive system from prenatal exposure to space radiation have become a hot topic that needs to be addressed. However, even for the ground experiments, such effects from exposure to high LET ionizing radiation are not as well studied as those for low LET ionizing radiations such as X-rays. Using the Heavy-Ion Medical Accelerator in Chiba (HIMAC) and Wistar rats, effects on gonads in prenatal male fetuses, on postnatal testicular development and on breeding activity of male offspring were studied following exposure of the pregnant animals to either accelerated carbon-ion beams with a LET value of about 13 keV/μm or neon-ion beams with a LET value of about 30 keV/μm at a dose range from 0.1 to 2.0 Gy on gestation day 15. The effects of X-rays at 200 kVp estimated for the same biological end points were studied for comparison. A significantly dose-dependent increase of apoptosis in gonocytes appeared 6 h after irradiations with a dose of 0.5 Gy or more. Measured delayed testis descent and malformed testicular seminiferous tubules were observed to be significantly different from the control animals at a dose of 0.5 Gy. These effects are observed to be dose- and LET-dependent. Markedly reduced testicular weight and testicular weight to body weight ratio were scored at postnatal day 30 even in the offspring that were prenatally irradiated with neon-ions at a dose of 0.1 Gy. A dose of 0.5 Gy from neon-ion beams induced a marked decrease in breeding activity in the prenatally irradiated male rats, while for the carbon-ion beams or X-rays, the significantly reduced breeding activity was observed only when the prenatal dose was at 1.0 Gy or more. These findings indicated that prenatal irradiations with heavy-ion beams on gestation day 15 generally induced markedly detrimental effects on prenatal gonads, postnatal testicular development and male

  11. Beam transfer line for food irradiation microtron at CAT

    International Nuclear Information System (INIS)

    A 10 MeV microtron is being developed at CAT for irradiation of food products. A beam transfer line comprising a 90 deg bending magnet, a quadrupole doublet and a rectangular scanning magnet has been designed to irradiate food products from the upper side. The bending magnet has an edge angle of 22.5 deg. The length of the beam transfer line has been minimized to keep the whole unit as compact as possible. The beam optics has been optimized keeping in view the requirement of a small beam pipe aperture (25mm radius) and a large range of circular as well as elliptical beam sizes on the food product. The speed of the conveyor belt has been assumed to be very small. The results of the beam optics chosen and the variation of the linear charge density on a food product during the scanning are presented in this paper. The effects of path length variation within the scanning magnet and beam size variation during a scanning are also discussed

  12. Effect of Pt:Sn atomic ratio on the preparation of PtSn/C electrocatalysts using electron beam irradiation

    International Nuclear Information System (INIS)

    PtSn/C electrocatalysts were prepared with Pt:Sn atomic ratios of 3:1, 1:1 and 1:3 in water/2-propanol using electron beam irradiation. The obtained materials were characterized by EDX, XRD and cyclic voltammetry. The ethanol electro-oxidation was studied by chronoamperometry. The XRD diffractograms of the PtSn/C electrocatalysts showed typical face-centered cubic (fcc) structure of platinum and the presence of a SnO2 phase (cassiterite). The mean crystallite sizes of Pt fcc phase was in the range of 3.0-3.5 nm. The PtSn/C electrocatalysts were active for ethanol electro-oxidation at room temperature and the material prepared with Pt:Sn atomic ratio of 1:1 showed the best activity. (author)

  13. Decoloration and mineralization of reactive dyes using electron beam irradiation, Part I: Effect of the dye structure, concentration and absorbed dose (single, binary and ternary systems)

    Science.gov (United States)

    Vahdat, Ali; Bahrami, S. Hajir; Arami, M.; Bahjat, A.; Tabakh, F.; Khairkhah, M.

    2012-07-01

    In this study, three different reactive dyes (C.I. Reactive Red 4, C.I. Reactive Blue 2 and C.I. Reactive Yellow 4) and their blend solutions were irradiated with 10 MeV electron beam. Effect of absorbed dose, dye structure and primary solution concentrations on the pH value changes, degree of decoloration and chemical oxygen demand (COD) removal of solutions were investigated. Results show that this method is effective in decomposition and decoloration of the dyes solutions. This method can be applied in mineralization of wastewater containing different dyes.

  14. Effects of E-Beam Irradiation on the Chemical, Physical, and Electrochemical Properties of Activated Carbons for Electric Double-Layer Capacitors

    Directory of Open Access Journals (Sweden)

    Min-Jung Jung

    2015-01-01

    Full Text Available Activated carbons (ACs were modified via e-beam irradiation at various doses for use as an electrode material in electric double-layer capacitors (EDLCs. The chemical compositions of the AC surfaces were largely unchanged by the e-beam irradiation. The ACs treated with the e-beam at radiation doses of 200 kGy exhibited higher nanocrystallinity than the untreated ACs. The specific surface areas and pore volumes of the e-beam irradiated ACs were also higher than those of the untreated ACs. These results were attributed to the transformation and degradation of the nanocrystallinity of the AC surfaces due to the e-beam irradiation. The specific capacitance of the ACs treated with the e-beam at radiation doses of 200 kGy increased by 24% compared with the untreated ACs, and the charge transfer resistance of the ACs was decreased by the e-beam irradiation. The enhancement of the electrochemical properties of the e-beam irradiated ACs can be attributed to an increase in their specific surface area and surface crystallinity.

  15. Screening of Mutation High-Yielding Biocontrol Bacterium BJ1 by Ion Beam Irradiation and Effect of Controlling Fusarium oxysporum cucunerinum Disease

    International Nuclear Information System (INIS)

    BJ1 of Bacillus subtilis is an important biocontrol factor in control of fungus disease. In order to improve the antagonistic ability of the strain,and obtain high-efficiency strains, 12C6+ of different doses and linear energy transfer (LET) was used to irradiate the biocontrol bacterium BJ1. The optimum dose and LET of ion beam irradiation for the BJ1 are 200-400 Gy and 60 keV/μm,respectively. The antagonistic ability is increased by 2%-21%. The control effect of mutation to Fusarium oxysporum f. sp. cucunerinum is increased by 17.48% over that of BJ1, and mutation also has better plant growth-promoting effect. (authors)

  16. Hydrodynamics of evaporating aerosols irradiated by intense laser beams

    International Nuclear Information System (INIS)

    An analysis is presented describing the interactions of atmospheric aerosols with a high-intensity laser beam propagating along an atmospheric path. For the case of moderate beam irradiances, diffusive mass transport and conductive energy transport dominate the aerosol-beam interactions. In this regime, the coupled aerosol-beam equations are solved numerically to obtain the spatic-temporal behavior of the propagating beam, and of the irradiated aerosols. For higher beam irradiances, convective transport of mass, energy and momentum away from the irradiated aerosols must be considered. The hydrodynamic equations are solved in the surrounding medium for this regime subject to appropriate ''jump conditions'' at the surface of the irradiated aerosol. Numerical examples illustrative of both regimes are given for the case of irradiated water aerosol droplets. 11 refs., 6 figs

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

    International Nuclear Information System (INIS)

    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

  18. Focused helium-ion beam irradiation effects on electrical transport properties of few-layer WSe2: enabling nanoscale direct write homo-junctions

    Science.gov (United States)

    Stanford, Michael G.; Pudasaini, Pushpa Raj; Belianinov, Alex; Cross, Nicholas; Noh, Joo Hyon; Koehler, Michael R.; Mandrus, David G.; Duscher, Gerd; Rondinone, Adam J.; Ivanov, Ilia N.; Ward, T. Zac; Rack, Philip D.

    2016-06-01

    Atomically thin transition metal dichalcogenides (TMDs) are currently receiving significant attention due to their promising opto-electronic properties. Tuning optical and electrical properties of mono and few-layer TMDs, such as tungsten diselenide (WSe2), by controlling the defects, is an intriguing opportunity to synthesize next generation two dimensional material opto-electronic devices. Here, we report the effects of focused helium ion beam irradiation on the structural, optical and electrical properties of few-layer WSe2, via high resolution scanning transmission electron microscopy, Raman spectroscopy, and electrical transport measurements. By controlling the ion irradiation dose, we selectively introduce precise defects in few-layer WSe2 thereby locally tuning the resistivity and transport properties of the material. Hole transport in the few layer WSe2 is degraded more severely relative to electron transport after helium ion irradiation. Furthermore, by selectively exposing material with the ion beam, we demonstrate a simple yet highly tunable method to create lateral homo-junctions in few layer WSe2 flakes, which constitutes an important advance towards two dimensional opto-electronic devices.

  19. Focused helium-ion beam irradiation effects on electrical transport properties of few-layer WSe2: enabling nanoscale direct write homo-junctions.

    Science.gov (United States)

    Stanford, Michael G; Pudasaini, Pushpa Raj; Belianinov, Alex; Cross, Nicholas; Noh, Joo Hyon; Koehler, Michael R; Mandrus, David G; Duscher, Gerd; Rondinone, Adam J; Ivanov, Ilia N; Ward, T Zac; Rack, Philip D

    2016-01-01

    Atomically thin transition metal dichalcogenides (TMDs) are currently receiving significant attention due to their promising opto-electronic properties. Tuning optical and electrical properties of mono and few-layer TMDs, such as tungsten diselenide (WSe2), by controlling the defects, is an intriguing opportunity to synthesize next generation two dimensional material opto-electronic devices. Here, we report the effects of focused helium ion beam irradiation on the structural, optical and electrical properties of few-layer WSe2, via high resolution scanning transmission electron microscopy, Raman spectroscopy, and electrical transport measurements. By controlling the ion irradiation dose, we selectively introduce precise defects in few-layer WSe2 thereby locally tuning the resistivity and transport properties of the material. Hole transport in the few layer WSe2 is degraded more severely relative to electron transport after helium ion irradiation. Furthermore, by selectively exposing material with the ion beam, we demonstrate a simple yet highly tunable method to create lateral homo-junctions in few layer WSe2 flakes, which constitutes an important advance towards two dimensional opto-electronic devices. PMID:27263472

  20. Focused helium-ion beam irradiation effects on electrical transport properties of few-layer WSe2: enabling nanoscale direct write homo-junctions

    Science.gov (United States)

    Stanford, Michael G.; Pudasaini, Pushpa Raj; Belianinov, Alex; Cross, Nicholas; Noh, Joo Hyon; Koehler, Michael R.; Mandrus, David G.; Duscher, Gerd; Rondinone, Adam J.; Ivanov, Ilia N.; Ward, T. Zac; Rack, Philip D.

    2016-01-01

    Atomically thin transition metal dichalcogenides (TMDs) are currently receiving significant attention due to their promising opto-electronic properties. Tuning optical and electrical properties of mono and few-layer TMDs, such as tungsten diselenide (WSe2), by controlling the defects, is an intriguing opportunity to synthesize next generation two dimensional material opto-electronic devices. Here, we report the effects of focused helium ion beam irradiation on the structural, optical and electrical properties of few-layer WSe2, via high resolution scanning transmission electron microscopy, Raman spectroscopy, and electrical transport measurements. By controlling the ion irradiation dose, we selectively introduce precise defects in few-layer WSe2 thereby locally tuning the resistivity and transport properties of the material. Hole transport in the few layer WSe2 is degraded more severely relative to electron transport after helium ion irradiation. Furthermore, by selectively exposing material with the ion beam, we demonstrate a simple yet highly tunable method to create lateral homo-junctions in few layer WSe2 flakes, which constitutes an important advance towards two dimensional opto-electronic devices. PMID:27263472

  1. EFFECT OF ELECTRONIC BEAM IRRADIATION ON DEVELOPMENT OF Plodia interpunctella(Hübner)%电子束辐照对印度谷螟发育的影响

    Institute of Scientific and Technical Information of China (English)

    范家霖; 张晓燕; 陈云堂; 李旭照; 郭东权; 吕晓华; 张建伟; 杨保安; 刘江豫; 田占军

    2011-01-01

    The electronic beam irradiation effects on different developed stages of Plodia interpunctella Hübner 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 Hübner to electron beam irradiation was: egglarvapupaeadult.The hatch rate,pupation rate,emergence rate and reproductive capacity significantly decreased with the increasing of irradiation dose(P0.05).The egg,larvae,pupae couldn't grow to adults after irradiation at 100,250 and 600Gy,respectively.No new generation adult was found after the adults were irradiated at 600Gy.It is concluded that 600Gy irradiation could be used as a suitable dose to prevent the reproduction of Plodia interpunctella Hübner during the storage of tobacco.%利用0~2kGy电子束对不同虫态的印度谷螟进行辐照处理,研究电子束辐照对卵、幼虫、蛹发育及成虫繁殖力的影响。结果表明,印度谷螟对电子束辐照的敏感性高低依次为:卵〉幼虫〉蛹〉成虫。辐照后试虫的孵化率、化蛹率、羽化率及成虫的繁殖力均随着辐照剂量的升高而显著降低。分别经100、250和600Gy的剂量辐照的卵、幼虫、蛹不能羽化为成虫,经600 Gy剂量辐照的成虫不能产生下一代成虫。因此,600Gy剂量的电子束辐照可以作为储烟有效防治印度谷螟的参考剂量。

  2. 电子束辐照杀菌对鱼粉品质的影响%EFFECT OF ELECTRON BEAM IRRADIATION ON THE QUALITY OF FISH MEAL

    Institute of Scientific and Technical Information of China (English)

    陈云堂; 范家霖; 吕晓华; 李湘; 商飞飞; 董威杰; 许勃

    2012-01-01

    采用0、0.83、1.56、2.30、4.93、7.84kGy不同剂量的电子束辐照鱼粉,研究其对鱼粉饲用品质的影响。结果表明:辐照吸收剂量为1.56kGy时鱼粉样品中细菌总数降至600CFU/g,霉菌总数低于10CFU/g;不同剂量的电子束辐照对鱼粉中粗蛋白、粗脂肪、水分、粗灰分、氨基酸的含量与组成影响不明显(p〉0.05);经电子束辐照后鱼粉中挥发性盐基氮含量有所增加(p〈0.05),但各辐照组间差异不明显(p〉0.05);电子束辐照对鱼粉酸价无影响(p〉0.05),但明显降低鱼粉的过氧化值(p〈0.05)。综合试验结果可确定,1.56~7.84kGy电子束辐照能有效控制鱼粉中的微生物,且不会对鱼粉的饲用品质产生不良影响。%Samples of soybean meal were exposed to electron beam with dosage levels of 0,0.83,1.56,2.30,4.93,7.84kGy,to evaluate the efficacy of electron beam for decontamination as well as the effect of electron beam irradiation on feeding quality of fish meal.The results showed that the total numbers of aerobic bacteria were reduced to 600CFU/g and fungi inhibited to 10CFU/g when fish meals were given an irradiation dose of 1.56kGy.Crude protein,crude fat,moisture,ash and amino acid composition were not significantly affected with electron beam irradiation(p0.05).Volatile basic nitrogen enhanced by electron beam irradiation(p0.05),but no significant difference was found for the fish meal irradiated with different dosage levels(p0.05).Total acidity value unchanged by irradiation,but peroxide value was decreased as the dosage increased(p0.05).It was concluded that the irradiation dosage of 1.56~7.84 kGy was very effective for microbial decontamination of fish meal,and did not adversely affect the nutritional quality of fish meal.

  3. Effects of a 2-step culture with cytokine combinations on megakaryocytopoiesis and thrombopoiesis from carbon-ion beam-irradiated human hematopoietic stem/progenitor cells

    International Nuclear Information System (INIS)

    To evaluate whether the continuous treatment of two cytokine combinations is effective in megakaryocytopoiesis and thrombopoiesis in hematopoietic stem/progenitor cells exposed to heavy ion beams, the effects of a 2-step culture by a combination of recombinant human interleukin-3 (IL-3)+stem cell factor (SCF)+thrombopoietin (TPO), which just slightly protected against carbon-ion beam-induced damages, and a combination of IL-3+TPO, which selectively stimulated the differentiation of the hematopoietic stem/progenitor cells to megakaryocytes and platelets, were examined. CD34+-hematopoietic stem/progenitor cells isolated from the human placental and umbilical cord blood were exposed to carbon-ion beams (linear energy transfer (LET)=50 keV/μm) at 2 Gy. These cells were cultured under three cytokine conditions. The number of megakaryocytes, platelets and hematopoietic progenitors were assessed using a flow cytometer and a clonogenic assay at 14 and 21 days after irradiation, respectively. However, the efficacy of each 2-step culture was equal or lower than that of using the IL-3+SCF+TPO combination alone and the 2-step culture could not induce megakaryocytes and platelets from hematopoietic stem/progenitor cells exposed to high LET-radiation such as carbon-ion beams. Therefore, additional cytokines and/or hematopoietic promoting compounds might be required to overcome damage to hematopoietic cells by high LET radiation. (author)

  4. Results of electron beam irradiation for tongue cancer

    International Nuclear Information System (INIS)

    From 1967 through 1988 183 previously untreated patients with squamous-cell carcinoma of the tongue were treated with electron beam irradiation. The patients were restaged as stage I (38 patients), stage II (64), stage III (58), and stage IV (28). For evaluable patients treated with intra-oral cone irradiation (IOC) alone (n=53) or combined with external irradiation (n=120), the two-year local control rate was 85% for T1, 73% for T2, and 58% for T3. According to clinical features, it was 80% for tumorous type, 68% for small ulceration type, and 53% for large ulceration type. In comparing uneven and even fractionated irradiation procedures, there was no significant difference in two-year local control rate (68% for uneven fractionated irradiation vs. 61% for even fractionated irradiation). When restricting to T2 and T3 patients, it was significantly higher for uneven fractionated irradiation (77% and 63%) than even fractionated irradiation (56% and 40%). In comparing T3 patients categorized as having >1000 mm2 (I) with those as having ≤1000 mm2 (II). the two-year local control rate was 48% for category I and 72% for category II. For T3 patients, it was 43% when associated with ulcer, as compared with 74% without it. The actuarial five-year survival rate was 92% for stage I, 72% for stage II, 67% for stage III, and 12% for stage IV. Delayed radiation ulcer and bone exposure were seen in 22 and 7 patients, respectively. In conclusion, IOC is comparable to internal irradiation and is clinically effective for T1 through T3 (in smaller size) tongue cancer. (N.K.)

  5. Ripple formation on nickel irradiated with radially polarized femtosecond beams.

    Science.gov (United States)

    Tsibidis, George D; Skoulas, Evangelos; Stratakis, Emmanuel

    2015-11-15

    We report on the morphological effects induced by the inhomogeneous absorption of radially polarized femtosecond laser irradiation of nickel (Ni) in sub-ablation conditions. A theoretical prediction of the morphology profile is performed, and the role of surface plasmon excitation in the production of self-formed periodic ripple structures is evaluated. Results indicate a smaller periodicity of the ripples profile compared to that attained under linearly polarized irradiation conditions. A combined hydrodynamical and thermoelastic model is presented in laser beam conditions that lead to material melting. The simulation results are presented to be in good agreement with the experimental findings. The ability to control the size of the morphological changes via modulating the beam polarization may provide an additional route for controlling and optimizing the outcome of laser micro-processing.

  6. Hardness modification of Al–Mg–Si alloy by using energetic ion beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ueyama, D. [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Saitoh, Y. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Ishikawa, N. [Tokai Research and Development Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Ohmura, T. [Structural Metals Center, National Institute for Materials Science, Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Semboshi, S. [Kansai-Center, Institute of Materials Research, Tohoku University, Sakai, Osaka 599-8531 (Japan); Hori, F. [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Iwase, A., E-mail: iwase@mtr.osakafu-u.ac.jp [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan)

    2015-05-15

    So far, we have irradiated Al–Mg–Si alloy with 5.4–16 MeV several ions at room temperature, and have found that ion irradiation is a useful tool for controlling the surface hardness for Al–Mg–Si alloys. In the present study, we tried several experiments as some applications of ion beam irradiation for hardness modifications of Al–Mg–Si alloy. Main results are as follows; (1) the combination of ion beam irradiation and the subsequent thermal aging can be used as an effective tool for the hardness modification of Al–Mg–Si alloy, and (2) designated regions and areas of the specimen can be hardened by changing the energy of ion beam and producing the irradiated area and unirradiated area of the surface. Then, we can expand the possibility of the ion beam irradiation as a new process for the three-dimensional hardness modification of Al–Mg–Si alloy.

  7. A variable electron beam and its irradiation effect on optical and electrical properties of CdS thin films

    Indian Academy of Sciences (India)

    M Singh; Y K Vijay; B K Sharma

    2007-10-01

    A low energy electron accelerator has been constructed and tested. The electron beam can operate in low energy mode (100 eV to 10 keV) having a beam diameter of 8–10 mm. Thin films of CdS having thickness of 100 nm deposited on ITO-coated glass substrate by thermal evaporation method have been irradiated by electron beam in the above instrument. The – characteristic is found to be nonlinear before electron irradiation and linear after electron irradiation. The TEP measurement confirms the n-type nature of the material. The TEP and – measurements also confirm the modification of ITO/CdS interface with electron irradiation.

  8. A study on the effect of low energy ion beam irradiation on Au/TiO2 system for its application in photoelectrochemical splitting of water

    Science.gov (United States)

    Verma, Anuradha; Srivastav, Anupam; Sharma, Dipika; Banerjee, Anamika; Sharma, Shailja; Satsangi, Vibha Rani; Shrivastav, Rohit; Avasthi, Devesh Kumar; Dass, Sahab

    2016-07-01

    Nanostructured TiO2 thin films were deposited on indium tin oxide (ITO) substrate via sol-gel technique and were modified by plasmonic Au layer. The plasmonic Au modified TiO2 (Au/TiO2) thin films were then irradiated with 500 keV Ar2+ ion beam at different ion fluences viz. 1 × 1016, 3 × 1016 and 1 × 1017 to study the effect of nuclear energy deposition on the morphology, crystallinity, band gap, surface plasmon resonance (SPR) peak exhibited by Au particles and photoelectrochemical properties of the system. Prepared thin films were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), Rutherford backscattering spectrometry (RBS) measurements and UV-visible spectroscopy. The photoelectrochemical measurements revealed that both Au/TiO2 and Au/TiO2 thin film irradiated at 1 × 1016 fluence exhibits enhanced photoelectrochemical response in comparison to pristine TiO2. The film irradiated at 1 × 1016 fluence offered maximum applied bias photon-to-current efficiency (ABPE) and shows 6 times increment in photocurrent density which was attributed to more negative flat band potential, maximum decrease in band gap, high open circuit voltage (Voc) and reduced charge transfer resistance.

  9. Effect of antioxidants on thiobarbituric acid reactive substances of mechanically de boned chicken meat irradiated with ionizing radiation: cobalt-60 and electron beam sources

    Energy Technology Data Exchange (ETDEWEB)

    Brito, Poliana de Paula; Azevedo, Heliana de; Pomarico Neto, Walter; Roque, Claudio Vitor; Brusqui, Armando Luiz, E-mail: hgomes@cnen.gov.b, E-mail: pbrito@cnen.gov.b, E-mail: cvroque@cnen.gov.b, E-mail: abrusqui@cnen.gov.b [Brazilian Nuclear Energy Commission (LAPOC/CNEN), Pocos de Caldas, MG (Brazil); Haguiwara, Marcia Mayumi Harada; Miyagusku, Luciana, E-mail: marciamh@ital.gov.b, E-mail: lucianam@ital.gov.b [Food Technology Institute (ITAL), SP (Brazil). Meat Technology Center

    2011-07-01

    Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 - A1 (0.3% Sodium Polyphosphate and Sodium Erythorbate 0.05%) and Antioxidant 2 - A2 (Rosemary Extract 0.02% and {alpha}-Tocopherol 0.01%). The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (Cn/I), with antioxidant A1 and non-irradiated (A1n/I), with antioxidant A2 and non-irradiated (A2n/I) without antioxidant and irradiated in Cobalt-60 source (CCo), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). Each 100 g sample was conditioned in a transparent, low density polyethylene oxygen permeable bag, frozen overnight at a temperature of -18 +- 1 deg C in a chamber, and irradiated in this state, maintaining the temperature low with dry ice. The samples were irradiated with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy.h{sup -1}) and electron beam (2.9 kGy.s{sup -1}). After this process, the samples were evaluated during the refrigeration period (2 +- 1 deg C) for 11 days for the following analysis: total psychotropic bacteria count, thiobarbituric acid reactive substances (TBARS). The addition of antioxidants was able to reduce lipid oxidation caused by the irradiation. There were no differences between the radiation sources used in the same parameters. The better antioxidants mixture in the TBARS reducing it was rosemary extract and {alpha}-tocopherol (A2). (author)

  10. Effect of antioxidants on thiobarbituric acid reactive substances of mechanically de boned chicken meat irradiated with ionizing radiation: cobalt-60 and electron beam sources

    International Nuclear Information System (INIS)

    Samples of MDCM with skin were divided into three groups: control (without antioxidants), Antioxidant 1 - A1 (0.3% Sodium Polyphosphate and Sodium Erythorbate 0.05%) and Antioxidant 2 - A2 (Rosemary Extract 0.02% and α-Tocopherol 0.01%). The three batches of samples were divided into nine groups: no antioxidant and non-irradiated (Cn/I), with antioxidant A1 and non-irradiated (A1n/I), with antioxidant A2 and non-irradiated (A2n/I) without antioxidant and irradiated in Cobalt-60 source (CCo), with antioxidant A1 irradiated in Cobalt 60 source (A1Co) with antioxidant A2 irradiated in Cobalt-60 source (A2Co) with antioxidant A1 irradiated in Electron beam (A1Eb) and with antioxidant A2 irradiated in Electron beam (A2Eb). Each 100 g sample was conditioned in a transparent, low density polyethylene oxygen permeable bag, frozen overnight at a temperature of -18 +- 1 deg C in a chamber, and irradiated in this state, maintaining the temperature low with dry ice. The samples were irradiated with a dose of 3.0 kGy, used two sources of radiation: Cobalt-60 (3.1 kGy.h-1) and electron beam (2.9 kGy.s-1). After this process, the samples were evaluated during the refrigeration period (2 +- 1 deg C) for 11 days for the following analysis: total psychotropic bacteria count, thiobarbituric acid reactive substances (TBARS). The addition of antioxidants was able to reduce lipid oxidation caused by the irradiation. There were no differences between the radiation sources used in the same parameters. The better antioxidants mixture in the TBARS reducing it was rosemary extract and α-tocopherol (A2). (author)

  11. Au2+ ion-beam irradiation effects on optical properties of CdSe and CdS quantum dots

    International Nuclear Information System (INIS)

    The effects of Au+ ion irradiation on the optical properties of CdS and CdSe quantum dots synthesized by chemical methods are studied. The ion-induced changes are studied using UV/Vis absorption, fluorescence spectroscopy and transmission electron microscopy experimental methods. It is observed that the size of the particle is found to increase with the ion fluence resulting in a shift of optical absorption peak to longer wavelength and confirmed by transmission electron microscopy measurements. The nonlinear optical properties are studied through Z-scan technique. These quantum dots show multiphoton absorption properties with 800 nm wavelength, 110 femtosecond laser pulse excitations. The photoluminescence studies show the emission peak shift to higher wavelength with the ion fluence

  12. Permeation of gases through electron-beam-irradiated polymer films

    International Nuclear Information System (INIS)

    The permeation of CO2, CH4, O2, N2, SF6, and He was measured at 35deg C in electron-beam-irradiated polymer films such as 1,2-polybutadiene (PB), polycarbonate (PC), polydimethylsiloxane (PDMS), poly(ethylene terephthalate) (PET), poly(4-methylpentene-1) (PMP), and polypropylene (PP). The permeability coefficients of the gases in PB decreased and those in PP increased with increasing irradiation dose, while those of PC, PDMS, PET, and PMP were virtually unaffected by irradiation. These results were attributed to the radiation effects of crosslinking in PB and degradation in PP. PC, PDM, PET, and PMP were insensitive to radiation, which accounts for the little change in permeation behavior. The decreases in permeability coefficients of the gases in irradiated PB films were attributed to changes in diffusivity, while solubility was not greatly affected. The dependence of permeability coefficients on crosslinking density of the irradiated PB films was also discussed. Decreases in permeability and diffusion coefficients were interpreted as due to decrease of free-volume content by crosslinking. The diffusion coefficient showed an approximately exponential relationship to the reciprocal of the average molecular weight between crosslinks (M-barc) over a range of M-barc between 200 and 20000. This suggests that the free-volume of the crosslinked polymer may be proportional to M-barc. (author)

  13. The effect of intense pulsed electron beam irradiation on the adhesion of NiCrAlY arc-vacuum coatings of gas turbine engine blades from GhS26NK alloy

    International Nuclear Information System (INIS)

    The present paper reviews the experimental results dedicated to the effect of irradiating conditions with intense pulsed electron beams on the adhesion of NiCrAlY resistant coatings to gas turbine engine blades from GhS26NK alloy. It is shown that intense pulsed electron beam of microsecond duration is high effective instrument for repair of turbine blades from refractory nickel alloys with resistant coatings. (authors)

  14. From the coupling between ion beam analysis techniques and physico-chemical characterization methods to the study of irradiation effects on materials behaviour

    International Nuclear Information System (INIS)

    The general purpose of my research work is to follow and to interpret the surface evolution of materials, which have received several treatments. During my PhD and my post-doc work, my field of research was tribology. Since I arrived in the 'Aval du Cycle Electronucleaire' group of the Institut de Physique Nucleaire de Lyon, my research activities are in line with the CNRS program 'PACE ' (Programme sur l'Aval du Cycle Electronucleaire) within the ACTINET network. They are coordinated by the PARIS (Physico-chimie des actinides et autres radioelements en solution et aux interfaces) and NOMADE (NOuveaux MAteriaux pour les DEchets) GDR with ANDRA (Agence Nationale pour la gestion des Dechets RAdioactifs), EDF and IRSN (Institut de Radioprotection et de Surete Nucleaire) as partner organisations. My work focused on the study of fission products and actinides migration in barrier materials, which may be capable of assuring the long term safety of deep geological repositories. Until now, it was necessary to use the coupling of ion beam analysis techniques and physico-chemical characterization techniques. During the last few months, I have became interested in understanding radiolytic effects. This new orientation has led us to use ion beams as an irradiating tool. These irradiation experiments are pursued in three major projects. The study of cobalt sulfide inhibition effects of radiolysis gas production during the irradiation of model organic molecules. This is a collaboration with the IRSN, the Institut de Recherche sur la Catalyse and the Ecole Nationale Superieure des Mines de Saint-Etienne. A PhD, co-directed by M. Pijolat from ENSMSE and myself, concerning this study will start in October 2003. Water radiolysis effects on iron corrosion are also studied in the particular case of vitrified nuclear waste containers, which will be stored in deep geological repositories. One ANDRA financed PhD, co-directed by Nathalie Moncoffre and myself, is dedicated to this study

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

    International Nuclear Information System (INIS)

    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 1H-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.

  16. 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.

  17. Simulation of Electron-Beam Irradiation of Skin Tissue Model

    Energy Technology Data Exchange (ETDEWEB)

    Miller, John H.; Suleiman, Atef; Chrisler, William B.; Sowa, Marianne B.

    2011-01-03

    Monte Carlo simulation of electrons stopping in liquid water was used to model the penetration and dose distribution of electron beams incident on the full-thickness EpiDermTM skin model (MatTek, Ashland, VA). This 3D tissue model has a fully developed basement membrane separating an epidermal layer of keratinocytes in various stages of differentiation from a dermal layer of fibroblast embedded in collagen. The simulations were motivated by a desire to selectively expose the epidermal layer to low linear-energy-transfer (LET) radiation in the presence of a non-irradiated dermal layer. Using the variable energy electron microbeam at the Pacific Northwest National Laboratory (PNNL) as a model of device characteristics and irradiation geometry, we find that at the highest beam energy available (90 keV), the estimated 90th percentile of penetration remains in the epidermal layer. To investigate the depth-dose distribution, we calculated lineal energy spectra for 10um thick layers near the 10th, 50th, and 90th percentile of penetration by the 90 keV electron beam. Biphasic spectra showed an increasing component of "stoppers" with increasing depth. Despite changes in the lineal energy spectra, the main effect on dose deposition with increasing depth is the screening effect of tissue above the layer of interest.

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

    International Nuclear Information System (INIS)

    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

  19. 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.

  20. 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.

  1. Application of electron-beam irradiation combined with antioxidants for fermented sausage and its quality characteristic

    Energy Technology Data Exchange (ETDEWEB)

    Lim, D.G.; Seol, K.H.; Jeon, H.J. [Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, San 56-1, Sillim-dong Gwanak-gu, Seoul 151-921 (Korea, Republic of); Jo, C. [Department of Animal Science and Biotechnology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Lee, M. [Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, San 56-1, Sillim-dong Gwanak-gu, Seoul 151-921 (Korea, Republic of)], E-mail: moohalee@snu.ac.kr

    2008-06-15

    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.

  2. Effects of prenatal irradiation with an accelerated heavy-ion beam on postnatal development in rats: II. Further study on neurophysiologic alterations

    Science.gov (United States)

    Wang, B.; Murakami, M.; Eguchi-Kasai, K.; Nojima, K.; Shang, Y.; Tanaka, K.; Watanabe, K.; Fujita, K.; Moreno, S. G.; Coffigny, H.; Hayata, I.

    Organogenesis is a highly radiosensitive period, study of prenatal exposure to high LET heavy ion beams on postnatal development is important for clarifying the radiation risk in space and promoting the evidence-based mechanism research. The effects from heavy ion irradiations are not well studied as those for low LET radiations such as X-rays in this field, even the ground-based investigations remain to be addressed. Using the Heavy Ion Medical Accelerator in Chiba (HIMAC) and Wistar rats, postnatal neurophysiological development in offspring was investigated following exposure of pregnant rats to accelerated neon-ion beams with a LET value of about 30 keV/μm at a dose range from 0.1 to 2.0 Gy on the 15th day of gestation. The age for appearance of four physiologic markers and attainment of five neonatal reflexes, and gain in body weight were monitored. Male offspring were evaluated as young adults using two behavioral tests including open field and hole-board dipping tests. The effects of X-rays at 200 kVp measured for the same biological end points were studied for comparison. For most of the endpoints at early age, significant neurophysiological alteration was observed even in offspring receiving 0.1 Gy of accelerated neon ions but not X-rays. All offspring receiving 2.0 Gy of accelerated neon ions died prior to weaning. Offspring prenatally irradiated with neon ions generally showed higher incidences of prenatal death, increased preweaning mortality, markedly delayed accomplishment in physiological markers and reflexes, significantly lower body weight and reduced ratios of main organ weight to body weight, and altered behavior compared to those exposed to X-rays at doses of 0.1 1.5 Gy. These findings indicate that irradiations with neon ions at 0.1 1.5 Gy on day 15 of gestation caused varied developmental alterations in offspring, and efficient dose leading to the detrimental effects seemed to be lower than that of X-rays.

  3. 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.

  4. Effect of electron beam irradiation and poly(vinylpyrrolidone addition on mechanical properties of polycaprolactone with empty fruit bunch fibre (OPEFB composite

    Directory of Open Access Journals (Sweden)

    2009-04-01

    Full Text Available Biodegradable composites or green composites were prepared by melt blending technique using polycaprolactone and oil palm empty fruit bunch fibre (OPEFB. Since OPEFB is not compatible with PCL a binder, poly(vinyl pyrrolidone, (PVP was used to improve the interaction between PCL and OPEFB. The composites produced were irradiated using electron beam to improve the mechanical properties. The tensile, flexural and impact strengths of PCL/OPEFB composites were improved by addition of 1% by weight of PVP and irradiated with 10 kGy of electron beam. The FTIR spectra indicate a slight increase of frequencies at C=O peaks from 1730 to 1732 cm–1 after irradiation indicates some interaction between C=O and O–H. The surface morphology of the facture surface obtained from tensile test shows no fibre pull out indicating good adhesion between the OPEFB and PCL after addition of PVP.

  5. Enhancement of Charpy impact value by electron beam irradiation of carbon fiber reinforced polymer

    International Nuclear Information System (INIS)

    Influences of electron beam irradiation on Charpy impact value of carbon fiber reinforced polymer (CFRP) have been investigated. The irradiation, which is one of short-time treatments, enhanced the Charpy impact value of CFRP. Furthermore, strengthening of carbon fiber, ductility enhancement of polymer and interface effects on impact test explains the impact value enhancement of CFRP. (author)

  6. 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.

  7. 200 MeV Ag15+ ion beam irradiation effects on spray deposited 5 wt% `Li' doped V2O5 thin film

    Science.gov (United States)

    Kovendhan, M.; Joseph, D. Paul; Manimuthu, P.; Sendilkumar, A.; Asokan, K.; Venkateswaran, C.; Mohan, R.

    2016-05-01

    Lithium 5 wt% doped V2O5 thin film was deposited onto ITO substrate by spray pyrolysis technique. The substrate temperature was kept at 450 °C. 200 MeV Ag15+ ion beams at a fluence of 5×1012 ions/cm2 was irradiated on 5 wt% `Li' doped V2O5 film of thickness 1367 nm. The XRD pattern confirms that the pristine film is non stoichiometry with orthorhombic structure and upon irradiation the crystallinity decreased and an obvious textured growth along (020) plane is induced. Raman peak observed at 917 cm-1 is due to oxygen deficiency. Upon irradiation, the optical transparency and band gap of the film decreased. Electrical transport property study shows that the resistivity increased by one order for the irradiated film.

  8. Stress, microstructure and evolution under ion irradiation in thin films grown by ion beam sputtering: modelling and application to interfacial effects in metallic multilayers

    International Nuclear Information System (INIS)

    We have investigated the formation of the interfacial chemical mixing in Mo/Ni multilayers, and particularly the influence of ballistic effects during the growth. For this purpose, hetero-epitaxial b.c.c./f.c.c. Mo(110)/Ni(111) multilayers were grown by two deposition methods: thermal evaporation and direct ion beam sputtering. As a preliminary, an accurate description of the stress state in pure sputtered Mo thin films was required. Microstructural and stress state analyses were essentially carried out by X-ray diffraction, and ion irradiation was used as a powerful tool to control the stress level. We showed that thermal evaporated thin films exhibit a weak tensile growth stress (∼ 0.6 GPa) that can be accounted for by the grain boundary relaxation model, whereas sputtered thin films develop large compressive growth stress (- 2 to - 4 GPa). This latter results from the bombardment of the growing film by the energetic particles involved during the sputtering process (atomic peening phenomenon), which induces the formation of defects in the layers, generating volume distortions. We thus developed a stress model that includes a hydrostatic stress component to account for these volume strains. This model allowed us to determine the 'unstressed and free of defects lattice parameter' a0, solely linked to chemical effects. For epitaxial Mo layers, it was possible to separate coherency stress from growth stress due to their distinct kinetic evolution during ion irradiation. Therefore, the stress analysis enabled us to determine the a0 values in Mo sub-layers of Mo/Ni superlattices. A tendency to the formation of an interfacial alloy is observed independently of the growth conditions, which suggests that thermodynamic forces favour the exchange mechanism. However, the extent of the intermixing effect is clearly enhanced by ballistic effects. (author)

  9. Ion beam irradiation effect on thermoelectric properties of Bi{sub 2}Te{sub 3} and Sb{sub 2}Te{sub 3} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Gaosheng [Department of Mechanical Engineering, Stony Brook University, Stony Brook, NY 11794 (United States); Zuo, Lei, E-mail: leizuo@vt.edu [Department of Mechanical Engineering, Stony Brook University, Stony Brook, NY 11794 (United States); Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24061 (United States); Lian, Jie [Department of Mechanical, Aerospace & Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Wang, Yongqiang [Materials Science & Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Chen, Jie [Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24061 (United States); Longtin, Jon [Department of Mechanical Engineering, Stony Brook University, Stony Brook, NY 11794 (United States); Xiao, Zhigang [Department of Electrical Engineering, Alabama A& M University, Normal, AL 35762 (United States)

    2015-09-01

    Thermoelectric energy harvesting is a very promising application in nuclear power plants for self-maintained wireless sensors. However, the effects of intensive radiation on the performance of thermoelectric materials under relevant reactor environments such as energetic neutrons are not fully understood. In this work, radiation effects of bismuth telluride (Bi{sub 2}Te{sub 3}) and antimony telluride (Sb{sub 2}Te{sub 3}) thermoelectric thin film samples prepared by E-beam evaporation are investigated using Ne{sup 2+} ion irradiations at different fluences of 5 × 10{sup 14}, 10{sup 15}, 5 × 10{sup 15} and 10{sup 16} ions/cm{sup 2} with the focus on the transport and structural properties. Electrical conductivities, Seebeck coefficients and power factors are characterized as ion fluence changes. X-ray diffraction (XRD) and transmission electron microscopy (TEM) of the samples are obtained to assess how phase and microstructure influence the transport properties. Carrier concentration and Hall mobility are obtained from Hall effect measurements, which provide further insight into the electrical conductivity and Seebeck coefficient mechanisms. Positive effects of ion irradiations from Ne{sup 2+} on thermoelectric material property are observed to increase the power factor to 208% for Bi{sub 2}Te{sub 3} and 337% for Sb{sub 2}Te{sub 3} materials between fluence of 1 and 5 × 10{sup 15} cm{sup 2}, due to the increasing of the electrical conductivity as a result of ionization radiation-enhanced crystallinity. However, under a higher fluence, 5 × 10{sup 15} cm{sup 2} in this case{sub ,} the power factor starts to decrease accordingly, limiting the enhancements of thermoelectric materials properties under intensive radiation environment.

  10. Effect of electron beam irradiation on the enzymatic degradation of composites based on biodegradable polymers and coconut fiber

    International Nuclear Information System (INIS)

    The development of polymeric materials that are susceptible to microbiological degradation and that have properties similar to the conventional polymers would reduce waste deposit. Degradable plastics suffer significant change on chemical structure when submitted to specific environmental condition. PCL and PLLA have been extensively investigated due to their bio-assimilation and because they are considered as eco-friendly. So the degradation of PCL and PLLA homopolymers, PCL:PLLA 20:80 (w:w) blend and coconut fiber-modified composites were studied by means of their degradation under lipase enzyme from Pseudomonas cepacia. Non-irradiated and EB-irradiated samples at 50 kGy and 100 kGy were exposed during 24, 72, 120 and 168 hours to the enzyme-buffer solution and the retained mass of dried samples was accompanied over time. The results were compared to the not submitted to the enzyme solution samples. Degradation rate of PCL was higher than PLLA in the presence of Pseudomonas lipase. PLLA presence reduced PCL's enzymatic degradation in the PCL:PLLA 20:80 w:w blend. After 120 h exposure, blend mass loss variation approached pure PLLA behavior. Composites degradation behavior through time was similar to the blend. Values of retained mass for composites were superior to the blends suggesting that coconut fiber did not significantly degrade in the period of test. Degradation rate of 50 kGy-irradiated PCL slightly reduced, and it was observed increase of degradation rate of samples irradiated with 100 kGy, probably attributed to its crystallinity decrease. Degradation rate of irradiated composite was similar to the blend, suggesting that fiber presence did not affect significantly this parameter. Samples tested during 168 h were affected by the water absorption by PLLA or coconut fibers through time testing. Studied samples degraded accentuatedly in the enzyme presence and were not negatively affected by the radiation processing. (author)

  11. Effect of electron beam irradiation on the enzymatic degradation of composites based on biodegradable polymers and coconut fiber

    Energy Technology Data Exchange (ETDEWEB)

    Kodama, Yasko; Bardi, Marcelo Augusto Goncalves; Machado, Luci Diva Brocardo, E-mail: ykodama@ipen.b, E-mail: marcelo.bardi@usp.b, E-mail: lmachado@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Rosa, Derval dos Santos, E-mail: derval.rosa@ufabc.edu.b [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil)

    2011-07-01

    The development of polymeric materials that are susceptible to microbiological degradation and that have properties similar to the conventional polymers would reduce waste deposit. Degradable plastics suffer significant change on chemical structure when submitted to specific environmental condition. PCL and PLLA have been extensively investigated due to their bio-assimilation and because they are considered as eco-friendly. So the degradation of PCL and PLLA homopolymers, PCL:PLLA 20:80 (w:w) blend and coconut fiber-modified composites were studied by means of their degradation under lipase enzyme from Pseudomonas cepacia. Non-irradiated and EB-irradiated samples at 50 kGy and 100 kGy were exposed during 24, 72, 120 and 168 hours to the enzyme-buffer solution and the retained mass of dried samples was accompanied over time. The results were compared to the not submitted to the enzyme solution samples. Degradation rate of PCL was higher than PLLA in the presence of Pseudomonas lipase. PLLA presence reduced PCL's enzymatic degradation in the PCL:PLLA 20:80 w:w blend. After 120 h exposure, blend mass loss variation approached pure PLLA behavior. Composites degradation behavior through time was similar to the blend. Values of retained mass for composites were superior to the blends suggesting that coconut fiber did not significantly degrade in the period of test. Degradation rate of 50 kGy-irradiated PCL slightly reduced, and it was observed increase of degradation rate of samples irradiated with 100 kGy, probably attributed to its crystallinity decrease. Degradation rate of irradiated composite was similar to the blend, suggesting that fiber presence did not affect significantly this parameter. Samples tested during 168 h were affected by the water absorption by PLLA or coconut fibers through time testing. Studied samples degraded accentuatedly in the enzyme presence and were not negatively affected by the radiation processing. (author)

  12. Irradiation of beam extraction equipment of the IHEP proton synchrotron

    International Nuclear Information System (INIS)

    The influence of the beam fast extraction on the slow extraction system septum-magnets irradiation is shown. The real meanings of beam extracting efficiency from U-70 are given. The proposals on lowering the radiating loadings on the equipment are presented. 16 refs.; 5 figs

  13. 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)

  14. Effects of irradiation

    International Nuclear Information System (INIS)

    The midday depression of CO2 assimilation in leaves of two cultivars of hazelnut. Effect of UV-B radiation on decay kinetics of long-term delayed luminiscence of green algae Scenedesmus quadricuda. Effects of irradiance on biomass allocation and needle photosynthetic capacity in silver fir seedlings originating from different localities. Chlorophyll fluorescence of UV-B irradiated bean leaves subjected to chilling in light. Preliminary studies on susceptibility of selected varieties of oats to high UV-B radiation dose. Influence of light conditions on oxidative stress in maize callus

  15. Effects of combined electron-beam irradiation and sous-vide treatments on microbiological and other qualities of chicken breast meat

    International Nuclear Information System (INIS)

    The microbiological safety, refrigeration shelf-life, and nutritional quality of chicken breast meat were investigated following combined electron-beam irradiation and cooking under vacuum (sous-vide). Chicken breast meat inoculated with 106 CFU/g of Listeria monocytogenes was irradiated with an electron beam at doses up to 3.1 kGy under vacuum in barrier bags, cooked in a boiling water bath for 3 min 45 s (previously determined to achieve an internal temperature of 71.1oC), and stored at 8oC for up to 5 weeks. Listeria was undetectable in samples treated with combined sous-vide and irradiation at 3.1 kGy, but the organism survived the sous-vide treatment without irradiation and multiplied during storage. A similar study, conducted with uninoculated chicken breast meat, revealed that the product which received both irradiation (3 kGy) and sous-vide treatment had a shelf-life of at least 8 weeks at 8oC, whereas the unirradiated samples treated sous-vide spoiled in 16 days. Listeria was undetectable in combination treated samples, but some of the unirradiated sous-vide samples tested after long storage showed high levels of Listeria. Some loss of thiamine occurred with the combined treatments. (author)

  16. Effects of combined electron-beam irradiation and sous-vide treatments on microbiological and other qualities of chicken breast meat

    Energy Technology Data Exchange (ETDEWEB)

    Shamsuzzaman, K.; Lucht, L.; Chuaqui-Offermanns, N

    1994-07-01

    The microbiological safety, refrigeration shelf-life, and nutritional quality of chicken breast meat were investigated following combined electron-beam irradiation and cooking under vacuum (sous-vide). Chicken breast meat inoculated with 10{sup 6} CFU/g of Listeria monocytogenes was irradiated with an electron beam at doses up to 3.1 kGy under vacuum in barrier bags, cooked in a boiling water bath for 3 min 45 s (previously determined to achieve an internal temperature of 71.1{sup o}C), and stored at 8{sup o}C for up to 5 weeks. Listeria was undetectable in samples treated with combined sous-vide and irradiation at 3.1 kGy, but the organism survived the sous-vide treatment without irradiation and multiplied during storage. A similar study, conducted with uninoculated chicken breast meat, revealed that the product which received both irradiation (3 kGy) and sous-vide treatment had a shelf-life of at least 8 weeks at 8{sup o}C, whereas the unirradiated samples treated sous-vide spoiled in 16 days. Listeria was undetectable in combination treated samples, but some of the unirradiated sous-vide samples tested after long storage showed high levels of Listeria. Some loss of thiamine occurred with the combined treatments. (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. Characteristics of PVDF Membranes Irradiated by Electron Beam.

    Science.gov (United States)

    Jaleh, Babak; Gavary, Negin; Fakhri, Parisa; Muensit, Nakatan; Taheri, Soheil Mohammad

    2015-01-01

    Polyvinylidene fluoride (PVDF) membranes were exposed vertically to a high energy electron beam (EB) in air, at room temperature. The chemical changes were examined by Fourier Transform Infrared Spectroscopy (FTIR). The surface morphologies were studied by Scanning Electron Microscopy (SEM) and showed some changes in the pore size. Thermogravimetric (TGA) analysis represented an increase in the thermal stability of PVDF due to irradiation. Electron paramagnetic resonance (EPR) showed the presence of free radicals in the irradiated PVDF. The effect of EB irradiation on the electrical properties of the membranes was analyzed in order to determine the dielectric constant, and an increase in the dielectric constant was found on increasing the dose. The surface hydrophilicity of the modified membrane was characterized by water contact angle measurement. The contact angle decreased compared to the original angle, indicating an improvement of surface hydrophilicity. Filtration results also showed that the pure water flux (PWF) of the modified membrane was lower than that of the unirradiated membrane. PMID:25569360

  19. Characteristics of PVDF Membranes Irradiated by Electron Beam

    Directory of Open Access Journals (Sweden)

    Babak Jaleh

    2015-01-01

    Full Text Available Polyvinylidene fluoride (PVDF membranes were exposed vertically to a high energy electron beam (EB in air, at room temperature. The chemical changes were examined by Fourier Transform Infrared Spectroscopy (FTIR. The surface morphologies were studied by Scanning Electron Microscopy (SEM and showed some changes in the pore size. Thermogravimetric (TGA analysis represented an increase in the thermal stability of PVDF due to irradiation. Electron paramagnetic resonance (EPR showed the presence of free radicals in the irradiated PVDF. The effect of EB irradiation on the electrical properties of the membranes was analyzed in order to determine the dielectric constant, and an increase in the dielectric constant was found on increasing the dose. The surface hydrophilicity of the modified membrane was characterized by water contact angle measurement. The contact angle decreased compared to the original angle, indicating an improvement of surface hydrophilicity. Filtration results also showed that the pure water flux (PWF of the modified membrane was lower than that of the unirradiated membrane.

  20. Behavior of nuclear materials irradiated with a dual ion beam

    Science.gov (United States)

    Thomé, Lionel; Velişa, Gihan; Debelle, Aurélien; Miro, Sandrine; Garrido, Frédérico; Trocellier, Patrick; Serruys, Yves

    2014-05-01

    Synergistic effects of nuclear (Sn) and electronic (Se) energy losses are investigated by comparing the damage accumulated in selected oxide (c-ZrO2, MgO, Gd2Ti2O7) and carbide (SiC) single crystals irradiated with single and dual low and high energy ion beams. Channeling results show that the Sn/Se synergy induces a strong decrease of the damage in MgO and SiC (where amorphization is prevented) and almost no effects in c-ZrO2 and Gd2Ti2O7. Raman and TEM results confirm this statement. The healing of defects generated by nuclear collisions in MgO and SiC is due to the electronic excitation produced in the wake of swift ions. These results present a strong interest for technological applications in the nuclear industry where expected cooperative Sn/Se effects may preserve the integrity of nuclear materials.

  1. Morphological and structural modifications of multiwalled carbon nanotubes by electron beam irradiation

    Science.gov (United States)

    Elsehly, Emad M.; Chechenin, N. G.; Makunin, A. V.; Motaweh, H. A.

    2016-10-01

    Effects of electron beam irradiation on a morphology and structure of multiwalled carbon nanotubes sample in a normal imaging regime of a scanning electron microscope (SEM) were investigated. Direct SEM observations give evidence that irradiation by electron beam in SEM eliminates morphological unevenness, in the form of round spots of white contrast, on the surface of carbon nanotubes (CNTs) and makes the tubes thinner. Electron dispersive analysis and Raman spectroscopy are used to explore the origin and nature of these spots. From this analysis we found that e-beam irradiation improves the CNTs graphitization. The synergy of thermal heating and ionization produced by the irradiation are discussed as possible mechanisms of the observed effects.

  2. Relation between track structure and LET effect on free radical formation for ion beam-irradiated alanine dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Krushev, V.V.; Koizumi, Hitoshi; Ichikawa, Tsuneki; Yoshida, Hiroshi [Hokkaido Univ., Sapporo (Japan). Faculty of Engineering; Shibata, Hiromi; Tagawa, Seiichi [Tokyo Univ. (Japan). Research Center for Nuclear Science and Technology; Yoshida, Yoichi [Tokyo Univ. (Japan). Faculty of Engineering

    1994-11-01

    The yield and local concentration of free radicals generated from alanine ({alpha}-aminopropionic acid) by irradiation with 3 MeV H{sup +} and He{sup +} ions were examined by means of electron spin resonance (ESR) and ESR power saturation methods at room temperature. The G-value of the radical formation showed a marked dependence on linear energy transfer (LET) of the ions. The G-value for the H{sup +} ion (average LET: 28 eV/nm) was almost the same as that for {gamma}-irradiation and it was smaller by a factor of 1/4.7 for the He{sup +} ion (average LET: 225eV/nm). Combining the local concentration of the free radicals along the ion tracks with the G-values and the reported ion range, the radius of a track filled with free radicals was estimated to be 4 {approx} 5 nm by assuming a simple rod-shaped track with a constant radius and homogeneous distribution of the free radicals in it. The track radius scarcely depends on the LET within the range examined. The radiation energy deposited in the core region of the ion track was concluded to spread over the rod to generate free radicals. (author).

  3. ESR investigations on ion beam irradiated polycarbonate

    Energy Technology Data Exchange (ETDEWEB)

    Chipara, M.I. (Institute for Physics and Technology of Materials, P.O. Box MG-7, Magurele, Bucharest, R-76900 (Romania)); Grecu, V.V. (University of Bucharest, Faculty of Physics, P.O. Box MG-11, Magurele, Bucharest, R-76900 (Romania)); Notingher, P.V. (University Politehnica of Bucharest, Electrotechnical Faculty, 313, Splaiul Independentei, Str., 77206 Bucharest (Romania)); Romero, J.R. (Universidad Central de Venezuela, Facultad de Ingineria, Dept. de Fisica Aplicada, Ciudad Universitaria, Chaguaramos, Caracas (Venezuela)); Chipara, M.D. (Research Institute for Electrotechnics, 45-47 Tudor Vladimirescu, Bd., Bucharest, R-79623 (Romania))

    1994-06-01

    Electron spin resonance (ESR) investigations with a polycarbonate solid state nuclear detector, irradiated with oxygen ions, are reported. The nature of the paramagnetic defects induced by irradiation is discussed. The temperature dependence of resonance line parameters is studied. From the experimental data, obtained by ESR, spectroscopy, the activation energy for defect recombination, the average isotropic exchange integral between paramagnetic defects as well as the average distance between defects, are estimated. Correlations with latent tracks structure are discussed. ((orig.))

  4. Simple model of bulk and surface excitation effects to inelastic scattering in low-energy electron beam irradiation of multi-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Kyriakou, Ioanna; Emfietzoglou, Dimitris [Medical Physics Lab, University of Ioannina Medical School, 451 10 Ioannina (Greece); Garcia-Molina, Rafael [Departamento de Fisica - CIOyN, Universidad de Murcia, E-30100 Murcia (Spain); Abril, Isabel [Departament de Fisica Aplicada, Universitat d' Alacant, Apartat 99, E-03080 Alacant (Spain); Kostarelos, Kostas [Nanomedicine Lab, Centre for Drug Delivery Research, The School of Pharmacy, University of London, London WC1N 1AX (United Kingdom)

    2011-09-01

    The effect of bulk and surface excitations to inelastic scattering in low-energy electron beam irradiation of multi-walled carbon nanotubes (MWNTs) is studied using the dielectric formalism. Calculations are based on a semiempirical dielectric response function for MWCNTs determined by means of a many-pole plasmon model with parameters adjusted to available experimental spectroscopic data under theoretical sum-rule constrains. Finite-size effects are considered in the context of electron gas theory via a boundary correction term in the plasmon dispersion relations, thus, allowing a more realistic extrapolation of the electronic excitation spectrum over the whole energy-momentum plane. Energy-loss differential and total inelastic scattering cross sections as a function of electron energy and distance from the surface, valid over the energy range {approx}50-30,000 eV, are calculated with the individual contribution of bulk and surface excitations separated and analyzed for the case of normally incident and escaping electrons. The sensitivity of the results to the various approximations for the spatial dispersion of the electronic excitations is quantified. Surface excitations are shown to have a strong influence upon the shape and intensity of the energy-loss differential cross section in the near surface region whereas the general notion of a spatially invariant inelastic mean free path inside the material is found to be of good approximation.

  5. Uniform irradiation system using beam scanning method for cyclotron

    International Nuclear Information System (INIS)

    JAERI AVF-cyclotron is equipped with an ion beam scanner for large area irradiation. The two-dimensional fluence distribution of ion beam obtained using cellulose triacetate film dosimeter was not uniform. This is resulted from the distortion of excitation current for electromagnet of the scanner. So, the beam scanning condition, i.e., the relation between the ion species, the beam profile and the scanning width, was extremely limited to make a good uniformity. We have developed a beam scanning simulator to get fluence distributions by calculation and then compared the simulated distributions with the measured ones. It was revealed that the both of them are in good agreement and the beam scanning condition to get good uniformity was led by using this simulator. On the basis of these results, the power supply of scanner was improved. A good uniformity of beam distribution was available. (author)

  6. Electron beam irradiation induces abnormal development and the stabilization of p53 protein of American serpentine leafminer, Liriomyza trifolii (Burgess)

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Hyun-Na; Yun, Seung-Hwan; Yoon, Changmann [Department of Plant Medicine, College of Agriculture, Life and Environment Sciences, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Kim, Gil-Hah, E-mail: khkim@chungbuk.ac.kr [Department of Plant Medicine, College of Agriculture, Life and Environment Sciences, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)

    2012-01-15

    The American serpentine leafminer fly, Liriomyza trifolii (Burgess), is one of the most destructive polyphagous pests worldwide. In this study, we determined electron beam doses for inhibition of normal development of the leaf miner and investigated the effect of electron beam irradiation on DNA damage and p53 stability. Eggs (0-24 h old), larvae (2nd instar), puparia (0-24 h old after pupariation) and adults (24 h after emergence) were irradiated with increasing doses of electron beam irradiation (six levels between 30 and 200 Gy). At 150 Gy, the number of adults that developed from irradiated eggs, larvae and puparia was lower than in the untreated control. Fecundity and egg hatchability decreased depending on the doses applied. Reciprocal crosses between irradiated and unirradiated flies demonstrated that males were more radiotolerant than females. Adult longevity was not affected in all stages. The levels of DNA damage in L. trifolii adults were evaluated using the alkaline comet assay. Our results indicate that electron beam irradiation increased levels of DNA damage in a dose-dependent manner. Moreover, low doses of electron beam irradiation led to the rapid appearance of p53 protein within 6 h; however, it decreased after exposure to high doses (150 Gy and 200 Gy). These results suggest that electron beam irradiation induced not only abnormal development and reproduction but also p53 stability caused by DNA damage in L. trifolii. We conclude that a minimum dose of 150 Gy should be sufficient for female sterilization of L. trifolii. - Highlights: > Electron beam irradiation inhibited normal development of the leaf miner. > Electron beam irradiation inhibited normal reproduction of the leaf miner. > Electron beam irradiation increased levels of DNA damage. > Electron beam irradiation induced p53 stability.

  7. 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)

  8. Propagation of Plasma Generated by Intense Pulsed Ion Beam Irradiation

    Institute of Scientific and Technical Information of China (English)

    WU Di; GONG Ye; LIU Jin-Yuan; WANG Xiao-Gang; LIU Yue; MA Teng-Cai

    2006-01-01

    @@ Taking the calculation results based on the established two-dimensional ablation model of the intense-pulsed-ion-beam (IPIB) irradiation process as initial conditions, we build a two-dimensional hydrodynamic ejection model of plasma produced by an IPIB-irradiated metal titanium target into ambient gas. We obtain the conclusions that shock waves generate when the background pressure is around 133 mTorr and also obtain the plume splitting phenomenon that has been observed in the experiments.

  9. 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.

  10. 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.

  11. Electron beam irradiation of gemstone for color enhancement

    International Nuclear Information System (INIS)

    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.

  12. Development of useful genetic resources by proton-beam irradiation

    International Nuclear Information System (INIS)

    The aim of this study is to develop new, useful and high-valuable genetic resources through the overproduction of biodegradable plastics and the propagation of wheat using proton-beam irradiation. Useful host strain was isolated through the mutagenization of the Escherichia coli K-12 strain, followed by characterizing the genetic and physiological properties of the E. coli mutant strains. The selected E. coli mutant strain produced above 85g/L of PHB, showed above 99% of PHB intracellular content and spontaneously liberated intracellular PHB granules. Based on the results, the production cost of PHB has been estimated to approximately 2$/kg, leading effective cost-down. Investigated the propagation of wheat and its variation, a selectable criterion of wet pro of was established and genetic analysis of useful mutant was carried out

  13. Mechanical properties of electron beam irradiated polyamide 6,6

    International Nuclear Information System (INIS)

    Radiation processing has been applied to improve product quality, energy saving and to manufacture products with special properties as a result of inducing reactions in solid state and at room temperature. This processing brings, many advantages comparing to the conventional chemical processing. Polyamide 6,6 due to its excellent mechanical, thermal and electrical properties and its great performance in multiple industrial applications is considered one of the most important engineering polymer. However, in specific applications, some of its properties need to be improved by means additives or fillers to reach the required properties, which increase its final cost. By these considerations, the aim of this work was to apply the ionizing radiation to improve the natural mechanical properties of polyamide 6,6. Also, to evaluate the irradiation parameters, and the mechanical performance of the irradiated polymer in order to use the cross-linking, induced by ionizing radiation, as substitute of additives and fillers. Therefore, Tensile, impact, hardness and wear properties of EB irradiated Polyamide 6,6 were evaluated under electron beam irradiation. Samples, of polyamide 6,6 without additives, for the mechanical tests, were injection-molded using a Battenfeld injector. These samples were irradiated with electrons at the IPEN irradiation facilities, using a Dynamitron JOB 188 electron accelerator with 1.5 MeV and 37.5 kW, and the doses were 70, 100, 150, and 200kGy. tives. Samples for tensile strength, impact, hardness and wear were injection-molded. These irradiated samples were conditioned at 23 deg. C and 50% humidity for 40 hours before being mechanically tested. The tensile strength, impact, hardness, and wear properties were evaluated according to standards ASTM D-680, ASTM D-256, ASTM D-2240, and ASTM D 1242 respectively. The tensile strength measurements were made with an EMIC Universal Testing Machine, model MEM-10000. The Izod Zwick Impact measurements were

  14. Morphological and biochemical responses of Oryza sativa L. (cultivar MR219) to ion beam irradiation

    Institute of Scientific and Technical Information of China (English)

    Anna Pick Kiong LING; Ying Chian UNG; Sobri HUSSEIN; Abdul Rahim HARUN; Atsushi TANAKA; Hase YOSHIHIRO

    2013-01-01

    Objective:Heavy ion beam, which has emerged as a new mutagen in the mutation breeding of crops and ornamental plants, is expected to result in the induction of novel mutations. This study investigates the morphological and biochemical responses of Oryza sativa toward different doses of carbon ion beam irradiation. Methods: In this study, the dry seeds of O. sativa were irradiated at 0, 20, 40, 60, 80, 100, and 120 Gy, fol owed by in-vitro germination under control ed conditions. Morphological and biochemical studies were conducted to investigate the morphological and physiological responses of O. sativa towards ion beam irradiation. Results: The study demonstrated that low doses (10 Gy) of ion beam have a stimulating effect on the height, root length, and fresh weight of the plantlets but not on the number of leaves. Meanwhile, doses higher than 10 Gy caused reductions in all the morphological parameters studied as compared to the control samples. The highest total soluble protein content [(2.11±0.47) mg/g FW] was observed in plantlets irradiated at 20 Gy. All irradiated plantlets were found to have 0.85%to 58.32%higher specific activity of peroxidase as compared to the control samples. The present study also revealed that low doses of ion beam (10 and 20 Gy) had negligible effect on the total chlorophyl content of O. sativa plantlets while 40 Gy had a stimulating effect on the chlorophyll content. Plantlets irradiated between 40 to 120 Gy were shown to be 0.38%to 9.98%higher in total soluble nitrogen content which, however, was not significantly different from the control samples. Conclusions:Carbon ion beam irradiation administered at low to moderate doses of 10 to 40 Gy may induce O. sativa mutants with superior characteristics.

  15. Food irradiation and its biological effects

    International Nuclear Information System (INIS)

    Irradiation of foods drew attention mostly in 1960s for disinfestation of food grains, spices and sprout inhibition in mainly potato and onion. γ-irradiation at 0.25 to 1 kGy dosage levels are usually used for irradiating grains, legumes, spices and sprout-prone vegetables. Irradiation of foods with in permissible dosage levels of 0.25 to 5 kGy is usually considered fairly safe from human consumption point of view not withstanding usual health concerns about its usage in foods. Irradiation of foods, in mostly solid or semi-solid form, at 5 kGy levels of γ-irradiation can achieve radicidation or, radiation equivalent of pasteurization and, if γ-irradiation is used at 10 kGy, it can achieve radappertization or, radiation equivalent of thermal commercial sterilization. However, the food industry uses γ-irradiation at 0.25 to 2 kGy only for mostly disinfestation of food grains/legumes, spices, sprout inhibition in potato and onion and, for surface sanitation of frozen fish, poultry and meat. Exposure to irradiation creates free radicals in foods that are capable of destroying some of the spoilage and pathogenic microflora but the same can also damage vitamins and enzymes besides creating some new harmful new chemical species, called unique radiolytic products (URPs), by combining with certain chemicals that a food may be laced with (like pesticides/fungicides). Exposure to high-energy electron beams are also known to create deleterious biological effects which may even lead to detection of trace amounts of radioactivity in the food. Some possible causes delineated for such harmful biological effects of irradiation include: irradiation induced vitamin deficiencies, the inactivity of enzymes in the foods, DNA damage and toxic radiolytic products in the foods. Irradiation, a non-thermal food preservation technique, has a role in salvaging enormous post harvest losses (25-30%) in developing economies to increase the per capita availability of foods. (author)

  16. Irradiation effects and micro-structural changes in large grain uranium dioxide fuel investigated by micro-beam X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Mieszczynski, C. [NES and SYN, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland); Kuri, G., E-mail: goutam.kuri@psi.ch [NES and SYN, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland); Degueldre, C.; Martin, M.; Bertsch, J.; Borca, C.N.; Grolimund, D. [NES and SYN, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland); Delafoy, Ch. [AREVA NP, 10 Rue Juliette Récamier, 69456 Lyon Cedex 06 (France); Simoni, E. [Institut de Physique Nucléaire, Université Paris-Sud, 91406 Orsay (France)

    2014-01-15

    Microstructural changes in a set of commercial grade UO{sub 2} fuel samples have been investigated using synchrotron based micro-focused X-ray fluorescence (μ-XRF) and X-ray diffraction (μ-XRD) techniques. The results are associated with conventional UO{sub 2} materials and relatively larger grain chromia-doped UO{sub 2} fuels, irradiated in a commercial light water reactor plant (average burn-up: 40 MW d kg{sup −1}). The lattice parameters of UO{sub 2} in fresh and irradiated specimens have been measured and compared with theoretical predictions. In the pristine state, the doped fuel has a somewhat smaller lattice parameter than the standard UO{sub 2} as a result of chromia doping. Increase in micro-strain and lattice parameter in irradiated materials is highlighted. All irradiated samples behave in a similar manner with UO{sub 2} lattice expansion occurring upon irradiation, where any Cr induced effect seems insignificant and accumulated lattice defects prevail. Elastic strain energy densities in the irradiated fuels are also evaluated based on the UO{sub 2} crystal lattice strain and non-uniform strain. The μ-XRD patterns further allow the evaluation of the crystalline domain size and sub-grain formation at different locations of the irradiated UO{sub 2} pellets.

  17. Irradiation effects and micro-structural changes in large grain uranium dioxide fuel investigated by micro-beam X-ray diffraction

    International Nuclear Information System (INIS)

    Microstructural changes in a set of commercial grade UO2 fuel samples have been investigated using synchrotron based micro-focused X-ray fluorescence (μ-XRF) and X-ray diffraction (μ-XRD) techniques. The results are associated with conventional UO2 materials and relatively larger grain chromia-doped UO2 fuels, irradiated in a commercial light water reactor plant (average burn-up: 40 MW d kg−1). The lattice parameters of UO2 in fresh and irradiated specimens have been measured and compared with theoretical predictions. In the pristine state, the doped fuel has a somewhat smaller lattice parameter than the standard UO2 as a result of chromia doping. Increase in micro-strain and lattice parameter in irradiated materials is highlighted. All irradiated samples behave in a similar manner with UO2 lattice expansion occurring upon irradiation, where any Cr induced effect seems insignificant and accumulated lattice defects prevail. Elastic strain energy densities in the irradiated fuels are also evaluated based on the UO2 crystal lattice strain and non-uniform strain. The μ-XRD patterns further allow the evaluation of the crystalline domain size and sub-grain formation at different locations of the irradiated UO2 pellets

  18. Ocular complications after external-beam irradiation - a literature overview

    International Nuclear Information System (INIS)

    Radiotherapy is one of the treatment methods applied to patients suffering from head and neck cancer. The efficiency of this method is comparable to surgery, yet it allows one to save the organ and avoid its permanent deformation. In the case of radiation not only the tumour is influenced but the surrounding, normal structures as well. Radiation causes deformation of normal structures as early or side effects. The aim of this study is to present plausible ocular complications after external beam irradiation of head and neck cancer, such as radiation- induced cataract, radiation retinopathy, dry-eye syndrome or radiation neuropathy. By the use of basic principles of radiotherapy planning we can avoid or minimize possible ocular complications occurring after irradiation. The treatment of ocular complications is difficult and very often does not give the expected outcome. Therefore, in such cases in order to restore vision surgery is required. This study shows that radiotherapy can be helpful but can increase the risk of occurrence of some ocular complications. (authors)

  19. Intensive irradiation of carbon nanotubes by Si ion beam

    Institute of Scientific and Technical Information of China (English)

    NI Zhichun; LI Qintao; YAN Long; GONG Jinlong; ZHU Dezhang; ZHU Zhiyuan

    2007-01-01

    Multi-walled carbon nanotubes were irradiated with 40 keV Si ion beam to a dose of 1×1017 cm-2. The multiple-way carbon nanowire junctions and the Si doping in carbon nanowires were realized. Moreover, the formation processes of carbon nanowire junctions and the corresponding mechanism were studied.

  20. NANOSTRUCTURE PATTERNING UNDER ENERGETIC PARTICLE BEAM IRRADIATION

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lumin [Regents of the University of Michigan; Lu, Wei [Regents of the University of Michigan

    2013-01-31

    Energetic ion bombardment can lead to the development of complex and diverse nanostructures on or beneath the material surface through induced self-organization processes. These self-organized structures have received particular interest recently as promising candidates as simple, inexpensive, and large area patterns, whose optical, electronic and magnetic properties are different from those in the bulk materials [1-5]. Compared to the low mass efficiency production rate of lithographic methods, these self-organized approaches display new routes for the fabrication of nanostructures over large areas in a short processing time at the nanoscale, beyond the limits of lithography [1,4]. Although it is believed that surface nanostructure formation is based on the morphological instability of the sputtered surface, driven by a kinetic balance between roughening and smoothing actions [6,7], the fundamental mechanisms and experimental conditions for the formation of these nanostructures has still not been well established, the formation of the 3-D naopatterns beneath the irradiated surface especially needs more exploration. During the last funding period, we have focused our efforts on irradiation-induced nanostructures in a broad range of materials. These structures have been studied primarily through in situ electron microscopy during electron or ion irradiation. In particular, we have performed studies on 3-D void/bubble lattices (in metals and CaF2), embedded sponge-like porous structure with uniform nanofibers in irradiated semiconductors (Ge, GaSb, and InSb), 2-D highly ordered pattern of nanodroplets (on the surface of GaAs), hexagonally ordered nanoholes (on the surface of Ge), and 1-D highly ordered ripple and periodic arrays (of Cu nanoparticles) [3,8-11]. The amazing common feature in those nanopatterns is the uniformity of the size of nanoelements (nanoripples, nanodots, nanovoids or nanofibers) and the distance separating them. Our research focuses on the

  1. Periodic Microstructures Formation on Plastic Plate by Aerosol Beam Irradiation

    Science.gov (United States)

    Tsukamoto, Masahiro; Abe, Nobuyuki; Morimoto, Junji; Akedo, Jun

    Technology of periodic microstructures formation on plastic plate, the polyethylene terephthalate (PET) plate, was developed with an aerosol beam. The beam was composed of submicron-size anatase titania (TiO2) particles. Formation mechanism depended on an incident angle of the beam to the PET plate. At an incident angles in the range of 0 to 30°C, a TiO2 films were fabricated on the PET plate. Deposition rate of the film decreased as incident angle increased in the range of 0 to 30°C. The film was not produced at 40°C. At 50 and 60°C, the PET plate was etched by the beam irradiation. In the etching area, periodic microstructures were self-organized, whose grooves’ direction was perpendicular to the beam incidence direction.

  2. Evaluation of antimicrobial and antibiofilm activity of electron beam irradiated endodontic sealer

    International Nuclear Information System (INIS)

    The complete disinfection of root canal is achieved by endodontic instrumentation, irrigation and medications followed by complete filling of the canal space by appropriate sealer. However careful cleaning and shaping of the canal system do not assure the complete eradication of microorganisms from tubular or lateral canals. Therefore, to avoid the possible growth of microorganisms, the filling endodontic material should have good antimicrobial effect on the pathogens causing root canal failure or pulpo-periapical pathosis. Zinc Oxide- Eugenol (ZOE) is the most commonly used filling material in endodontics. Electron beam (e-beam) radiation is a form of ionizing radiation known to induce physiochemical and biological changes in the irradiated substances. Hence, the present study was carried out to evaluate the effect of e-beam radiation on antimicrobial property of ZOE sealer against root canal pathogens like Enterococcus faecalis, Streptococcus mutans, Staphylococcus aureus and Candida albicans. The homogenous paste of Zinc oxide and Eugenol prepared by mixing at the ratio of 3:1 was loaded into the sterile molds of 6 mm diameter. After complete drying of paste, discs were aseptically separated from the mould. The prepared discs were subjected to e-beam irradiation of 250 Gy, 500 Gy, 750 Gy and 1000 Gy at Microtron Centre, Mangalore University. Antimicrobial and antibiofilm properties of control and irradiated sealer were determined by well diffusion method and growing the biofilm according to O'Toole method, respectively. The antimicrobial effect was observed only against S.aureus and C. albicans in non-irradiated ZOE. The ZOE sealer irradiated at 1000 Gy showed the significantly increased (P<0.001) antimicrobial effect against S. aureus and C. albicans. However, the substantially increased antibiofilm activity against C.albicans was noticed in the ZOE irradiated at 250 Gy. This study showed that e-beam irradiation at 1000 Gy and 250 Gy were found to be optimum

  3. The reactivity of plant, murine and human genome to electron beam irradiation

    International Nuclear Information System (INIS)

    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. 氧化锡气体传感器的电子束辐照效应%Effects of electron beam irradiation on SnO2 gas sensors

    Institute of Scientific and Technical Information of China (English)

    JIAO Zheng; WANG Deqing; LI Zhen; LU Senlin; WU Minghong

    2005-01-01

    There are many traditional ways to improve sensitivity and selectivity of semiconductor gas sensors, such as metal ions adulteration[1,2] and surface modification[3,4]. In this paper 1.75 MeV electron beam was used to modify surface structure of tin dioxide gas sensors, and the gas sensing characteristics were studied. Results showed that the sensitivity and selectivity of SnO2 sensors were improved after the electron beam irradiation.The experiment was conducted on a GJ-2-II type electron accelerator (Shanghai Xianfeng Co. Ltd.), with an E-beam of 1.75MeV and 2mA. SnO2 sensor samples were irradiated for 10, 30, 60, 120 and 240s, and the doses delivered to the samples were 7, 21, 42, 84 and 168 kGy, respectively. Sensitivities to hydrogen and ethanol of the sensors were measured before and after the irradiation. As shown in Fig. 1, after the irradiation, sensitivities of the SnO2 sensors were improved greatly. For 100μg g-1 hydrogen with the 42kGy irradiated sensor, the sensitivity increased from 7.7 to 9.5. Further increase of the dose, however, would not lead to further increase of the sensitivity. For 100 μg g-1 ethanol, the same results were observed.The energetic electrons injecting into the SnO2 generate defects and active species like O- and O2-, which react with reductive gases such as hydrogen or ethanol, and these increase the sensitivity. As the irradiation dose increases, more active species are produced, hence the increased sensitivity. By computer simulation, it was found that higher irradiation dose would introduce more defects inside the SnO2 layer, leading to a better response to surface gas adsorption. But when the irradiation dose increased to a certain level, the effects on the structure tended to be saturated, as shown in Figure 1, the sensitivity became smooth when the irradiation dose increased to more than 100 kGy.

  5. Electron beam and gamma ray irradiated polymer electrolyte films: Dielectric properties

    Directory of Open Access Journals (Sweden)

    S. Raghu

    2016-04-01

    Full Text Available In this study, polymer electrolyte films were irradiated with electron beam (EB and Gamma ray (GR at 50 and 150 kGy. The induced chemical changes in films due to irradiations have been confirmed from the Fourier Transform Infra red (FT-IR spectra. The X-ray Diffractometry (XRD results show that crystallinity decreases by ∼20% in EB and ∼10% in GR irradiated films respectively compared to non-irradiated film. The micro structural arrangement was investigated by Scanning Electronic Microscopy (SEM and the images reveal that there is a substantial improvement in the surface morphology in irradiated films. The real (ε′ and imaginary (ε″ dielectric constant and AC conductivity are found to increase with increase in irradiation dose. Improved dielectric properties and conductivity (1.74 x 10−4 & 1.15 x 10−4 S/cm, respectively, for EB and GR irradiated films at room temperature after irradiation and it confirm that EB and GR irradiation can be simple and effective route to obtaining highly conductive polymer electrolytes. From this study it is confirm that EB is more effectiveness than GR irradiation.

  6. Damage Characteristics of TiD2 Films Irradiated by a Mixed Pulsed Beam of Titanium and Hydrogen Ions

    Science.gov (United States)

    Liu, Meng; He, Tie; Yan, Jie; Ke, Jianlin; Lin, Jufang; Lu, Biao

    2016-07-01

    Titanium deuteride is an important nuclear material used in the field of nuclear technology, and further research is needed into TiD2 films irradiated by pulsed ion beams of the vacuum arc discharge with hydrogen. In the current study, these irradiated TiD2 films have been investigated using scanning electronic microscopy and slow positron annihilation techniques. Both the thermal effect and irradiation defects of TiD2 films were studied, following their irradiation with mixed pulsed ion beams of titanium and hydrogen ions. It is found that the thermal effect is trivial on the irradiated surfaces, and the dominant effect is irradiation defects which can be enhanced by repetitive shots and is characterized by the inner diffusion of irradiation defects.

  7. Mechanical and thermal properties of commercial multilayer PET/PP film irradiated with electron-beam

    International Nuclear Information System (INIS)

    The effects of electron-beam irradiation on mechanical and thermal properties, for one commercial flexible food packaging multilayer structure, were studied. The laminated poly(ethylene terephthalate) (PET)/ polypropylene (PP) structure was irradiated up to 60 kGy, using a 1.5 MeV electron beam accelerator, at room temperature in the presence of air. Mechanical properties showed significant changes (p < 0.05). In addition, the DSC analysis, after treatment, showed that the fusion enthalpy and crystallinity of the PET/PP structure components presented significant changes (p < 0.05) with the electron-beam radiation doses applied. It was observed an increase in PP crystallinity while the PET crystallinity decreases. Such decrease in PET crystallinity indicates the predominance of a cross-linking process on the irradiated PET layer; responsible for the increase in some mechanical properties of the studied film. (author)

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

    Science.gov (United States)

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

    2004-09-01

    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.

  9. 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.

  10. Structural and electrical properties of swift heavy ion beam irradiated Co/Si interface

    Indian Academy of Sciences (India)

    Garima Agarwal; Ankur Jain; Shivani Agarwal; D Kabiraj; I P Jain

    2006-04-01

    Synthesis of swift heavy ion induced metal silicide is a new advancement in materials science research. We have investigated the mixing at Co/Si interface by swift heavy ion beam induced irradiation in the electronic stopping power regime. Irradiations were undertaken at room temperature using 120 MeV Au ions at the Co/Si interface for investigation of ion beam mixing at various doses: 8 × 1012, 5 × 1013 and 1 × 1014 cm-2. Formation of different phases of cobalt silicide is identified by the grazing incidence X-ray diffraction (GIXRD) technique, which shows enhancement of intermixing and silicide formation as a result of irradiation. – characteristics at Co/Si interface were undertaken to understand the irradiation effect on conduction mechanism at the interface.

  11. Effect of electron beam irradiation on multi-walled carbon nanotubes%电子束辐照对多壁碳纳米管的影响

    Institute of Scientific and Technical Information of China (English)

    李斌; 凤仪; 丁克望; 钱刚; 张学斌; 刘衍芳

    2014-01-01

    在室温下采用透射电子显微镜中汇聚的电子束辐照多壁碳纳米管。结果表明,在能量为100 keV的电子束辐照下除了碳纳米管管壁有一些弯曲外没有其他结构被破坏;当电子能量增加到200 keV时,纳米管有明显的损伤,可以观察到纳米管的无定型化、纳米管外壁的凹坑和缺口。200 keV的电子束辐照还能形成碳洋葱和2根多壁纳米管的焊接。多壁碳纳米管的离位阀能为83~110 keV。能量超过阀能的电子束可以很轻易地损伤纳米管而低于阀能的电子束则很难损坏纳米管,其损伤机理为溅射和原子离位。%Multi-walled carbon nanotubes (MWCNTs) were irradiated with focused electron beams in a transmission electron microscope at room temperature. The results showed that carbon nanotubes had no obvious structural damages but only shell bending under 100 keV electron beam irradiation. However, when the electron energy increased to 200 keV, the nanotubes were damaged and amorphization, pits and gaps were detected. Furthermore, generating of carbon onions and welding between two MWCNTs occurred under 200 keV electron irradiation. It was easy to destroy the MWCNTs as the electron beams exceeded the displacement threshold energy that was calculated to be 83-110 keV. Conversely, the energy of electron beams below the threshold energy was not able to damage the tubes. The damage mechanism is sputtering and atom displacement.

  12. Comprehensive stabilization mechanism of electron-beam irradiated polyacrylonitrile fibers to shorten the conventional thermal treatment.

    Science.gov (United States)

    Park, Sejoon; Yoo, Seung Hwa; Kang, Ha Ri; Jo, Seong Mu; Joh, Han-Ik; Lee, Sungho

    2016-01-01

    An electron beam was irradiated on polyacrylonitrile (PAN) fibers prior to thermal stabilization. The electron-beam irradiation effectively shortened the thermal stabilization process by one fourth compared with the conventional thermal stabilization process. A comprehensive mechanistic study was conducted regarding this shortening of the thermal stabilization by electron-beam irradiation. Various species of chain radicals were produced in PAN fibers by electron-beam irradiation and existed for a relatively long duration, as observed by electron spin resonance spectroscopy. Subsequently, these radicals were gradually oxidized to peroxy radicals in the presence of oxygen under storage or heating. We found that these peroxy radicals (CO) enabled such an effective shortcut of thermal stabilization by acting as intermolecular cross-linking and partial aromatization points in the low temperature range (100-130 °C) and as earlier initiation seeds of successive cyclization reactions in the next temperature range (>130-140 °C) of thermal stabilization. Finally, even at a low irradiation dose (200 kGy), followed by a short heat treatment (230 °C for 30 min), the PAN fibers were sufficiently stabilized to produce carbon fibers with tensile strength and modulus of 2.3 and 216 GPa, respectively, after carbonization. PMID:27349719

  13. Comprehensive stabilization mechanism of electron-beam irradiated polyacrylonitrile fibers to shorten the conventional thermal treatment

    Science.gov (United States)

    Park, Sejoon; Yoo, Seung Hwa; Kang, Ha Ri; Jo, Seong Mu; Joh, Han-Ik; Lee, Sungho

    2016-06-01

    An electron beam was irradiated on polyacrylonitrile (PAN) fibers prior to thermal stabilization. The electron-beam irradiation effectively shortened the thermal stabilization process by one fourth compared with the conventional thermal stabilization process. A comprehensive mechanistic study was conducted regarding this shortening of the thermal stabilization by electron-beam irradiation. Various species of chain radicals were produced in PAN fibers by electron-beam irradiation and existed for a relatively long duration, as observed by electron spin resonance spectroscopy. Subsequently, these radicals were gradually oxidized to peroxy radicals in the presence of oxygen under storage or heating. We found that these peroxy radicals (CO) enabled such an effective shortcut of thermal stabilization by acting as intermolecular cross-linking and partial aromatization points in the low temperature range (100–130 °C) and as earlier initiation seeds of successive cyclization reactions in the next temperature range (>130–140 °C) of thermal stabilization. Finally, even at a low irradiation dose (200 kGy), followed by a short heat treatment (230 °C for 30 min), the PAN fibers were sufficiently stabilized to produce carbon fibers with tensile strength and modulus of 2.3 and 216 GPa, respectively, after carbonization.

  14. Plastic coating on paper by electron beam irradiation

    International Nuclear Information System (INIS)

    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.)

  15. The network and properties of the NR/SBR vulcanizate modified by electron beam irradiation

    International Nuclear Information System (INIS)

    A natural rubber/styrene butadiene rubber (NR/SBR) vulcanizate filled with carbon black was modified by high-energy electron beam (EB) irradiation in this work. The crosslinked structure was studied by a special chemical probe method. The influence of EB irradiation on mechanical properties, filler network, and dynamic properties including abrasion resistance, rolling resistance, and wet skid resistance was also investigated. The results revealed that the crosslink structure significantly changed after EB treatment, indicating that the amount of poly- and di-sulfide crosslinked bonds decreased and that of mono-sulfide bonds increased. The polymer–filler interaction was enhanced after EB irradiation. An EB dose of 600 kGy reduced the abrasion loss of the NR/SBR vulcanizate, and one of 300 kGy reduced the rolling resistance by 11.4%. Meanwhile, EB doses below 200 kGy had no obvious effect on the wet skid resistance. This EB-modified NR/SBR vulcanizate can be used to prepare high-performance tires with good abrasion resistance and low rolling resistance. - Highlights: • NR/SBR vulcanizate as a typical tread material is modified by electron beam. • Crosslinked structure of vulcanizate changes upon irradiation. • The interaction between polymer and fillers is enhanced after irradiation. • Rolling resistance and abrasion resistance are improved after irradiation. • Electron beam has no obvious effect on wet skid resistance below 200 kGy

  16. Quantitative Assessment of Amino Acid Damage upon keV Ion Beam Irradiation Through FTIR Spectroscopy

    Science.gov (United States)

    Huang, Qing; Ke, Zhigang; Su, Xi; Yuan, Hang; Zhang, Shuqing; Yu, Zengliang

    2010-06-01

    Ion beam irradiation induces important biological effects and it is a long-standing task to acquire both qualitative and quantitative assessment of these effects. One effective way in the investigation is to utilize Fourier transformation infrared (FTIR) spectroscopy because it can offer sensitive and non-invasive measurements. In this paper a novel protocol was employed to prepare biomolecular samples in the form of thin and transversely uniform solid films that were suitable for both infrared and low-energy ion beam irradiation experiments. Under the irradiation of N+ and Ar+ ion beams of 25 keV with fluence ranging from 5×1015 ions/cm2 to 2.5×10 ions/cm2, the ion radio-sensitivity of four amino acids, namely, glycine, tyrosine, methionine and phenylalanine, were evaluated and compared. The ion beam irradiation caused biomolecular decomposition accompanied by molecular desorption of volatile species and the damage was dependent on ion type, fluence, energy and types of amino acids. The effectiveness of application of FTIR spectroscopy to the quantitative assessment of biomolecular damage dose effect induced by low-energy ion radiation was thus demonstrated.

  17. A study about the effects of gamma radiation and electron beam irradiation in the detection of genetically modified maize (Zea Mays)

    International Nuclear Information System (INIS)

    Cell-220 and electron beam irradiation (Radiation Dynamics Inc. USA) were used (Atomic Energy of Canada, LTD), applying doses of 1, 25 and 50 kGy. After irradiating the samples, the detection results were compared with non-irradiated samples, showing that, when the PCR technique, was used, the irradiation does not affect the perception of the genetically modified maize. (author)

  18. Electron beam irradiation induces abnormal development and the stabilization of p53 protein of American serpentine leafminer, Liriomyza trifolii (Burgess)

    Science.gov (United States)

    Koo, Hyun-Na; Yun, Seung-Hwan; Yoon, Changmann; Kim, Gil-Hah

    2012-01-01

    The American serpentine leafminer fly, Liriomyza trifolii (Burgess), is one of the most destructive polyphagous pests worldwide. In this study, we determined electron beam doses for inhibition of normal development of the leaf miner and investigated the effect of electron beam irradiation on DNA damage and p53 stability. Eggs (0-24 h old), larvae (2nd instar), puparia (0-24 h old after pupariation) and adults (24 h after emergence) were irradiated with increasing doses of electron beam irradiation (six levels between 30 and 200 Gy). At 150 Gy, the number of adults that developed from irradiated eggs, larvae and puparia was lower than in the untreated control. Fecundity and egg hatchability decreased depending on the doses applied. Reciprocal crosses between irradiated and unirradiated flies demonstrated that males were more radiotolerant than females. Adult longevity was not affected in all stages. The levels of DNA damage in L. trifolii adults were evaluated using the alkaline comet assay. Our results indicate that electron beam irradiation increased levels of DNA damage in a dose-dependent manner. Moreover, low doses of electron beam irradiation led to the rapid appearance of p53 protein within 6 h; however, it decreased after exposure to high doses (150 Gy and 200 Gy). These results suggest that electron beam irradiation induced not only abnormal development and reproduction but also p53 stability caused by DNA damage in L. trifolii. We conclude that a minimum dose of 150 Gy should be sufficient for female sterilization of L. trifolii.

  19. Electron beam inactivation of Tulane virus on fresh produce, and mechanism of inactivation of human norovirus surrogates by electron beam irradiation.

    Science.gov (United States)

    Predmore, Ashley; Sanglay, Gabriel C; DiCaprio, Erin; Li, Jianrong; Uribe, R M; Lee, Ken

    2015-04-01

    Ionizing radiation, whether by electron beams or gamma rays, is a non-thermal processing technique used to improve the microbial safety and shelf-life of many different food products. This technology is highly effective against bacterial pathogens, but data on its effect against foodborne viruses is limited. A mechanism of viral inactivation has been proposed with gamma irradiation, but no published study discloses a mechanism for electron beam (e-beam). This study had three distinct goals: 1) evaluate the sensitivity of a human norovirus surrogate, Tulane virus (TV), to e-beam irradiation in foods, 2) compare the difference in sensitivity of TV and murine norovirus (MNV-1) to e-beam irradiation, and 3) determine the mechanism of inactivation of these two viruses by e-beam irradiation. TV was reduced from 7 log10 units to undetectable levels at target doses of 16 kGy or higher in two food matrices (strawberries and lettuce). MNV-1 was more resistant to e-beam treatment than TV. At target doses of 4 kGy, e-beam provided a 1.6 and 1.2 log reduction of MNV-1 in phosphate buffered saline (PBS) and Dulbecco's Modified Eagle Medium (DMEM), compared to a 1.5 and 1.8 log reduction of TV in PBS and Opti-MEM, respectively. Transmission electron microscopy revealed that increased e-beam doses negatively affected the structure of both viruses. Analysis of viral proteins by SDS-PAGE found that irradiation also degraded viral proteins. Using RT-PCR, irradiation was shown to degrade viral genomic RNA. This suggests that the mechanism of inactivation of e-beam was likely the same as gamma irradiation as the damage to viral constituents led to inactivation. PMID:25590261

  20. Unraveling the mystery of enhanced cell-killing effect around the Bragg peak region of a double irradiation source 9C-ion beam

    Institute of Scientific and Technical Information of China (English)

    LI Qiang; Y. Furusawa; M. Kanazawa; A. Kitagawa

    2005-01-01

    An enhanced cell-killing effect at the penetration depths around the Bragg peak of a β-delayed particle decay 9C-ion beam has been observed in our preceding radiobiological experiments in comparison with a therapeutic 12C beam under the same conditions, and RBE values of the 9C beam were revealed to be higher than those of the comparative 12C beam by a factor of up to 2. This study is aimed at investigating the biophysical mechanisms underlying the important experimental phenomenon. First of all, a model for calculating the stopping probability density of the experimentally applied 9C beam is worked out, where all determinants such as the initial momentum spread of the 9C beam, the fluence attenuation with penetration depth due to the projectile-target nuclear reaction and the energy straggling effect are taken into account. On the basis of the calculated 9C-ion stopping distribution, it has been found that the area corresponding to the enhanced cell-killing effect of the 9C beam appears at the stopping region of the incident 9C ions. The stopping 9C-ion density in depth, then, is derived from the calculated probability density. Moreover, taking entrance dose 1 Gy for the 9C beam as an example, the average stopping 9C-ion numbers per cell at various depths are deduced. Meanwhile, the mean lethal damage events induced by the 9C and comparative 12C beams at the depths with almost equal dose-averaged LETs are derived from the measured cell surviving fractions at these depths for the 9C and 12C beams. Under the condition of the same absorbed doses, there are indeed good agreements between the average stopping 9C-ion number pre cell and the difference of the mean lethal damage events between the 9C and 12C beams at the depths of similar dose-averaged LETs. It can be inferred that if a 9C ion comes to rest in a cell, the cell would undergo dying. In view of the decay property of 9C nuclide, clustered damage would be caused in the cell by the emitted low-energy particles

  1. In situ formation of bismuth nanoparticles through electron-beam irradiation in a transmission electron microscope

    Science.gov (United States)

    Sepulveda-Guzman, S.; Elizondo-Villarreal, N.; Ferrer, D.; Torres-Castro, A.; Gao, X.; Zhou, J. P.; Jose-Yacaman, M.

    2007-08-01

    In this work, bismuth nanoparticles were synthesized when a precursor, sodium bismuthate, was exposed to an electron beam at room temperature in a transmission electron microscope (TEM). The irradiation effects were investigated in situ using selected-area electron diffraction, high-resolution transmission electron microscopy and x-ray energy dispersive spectroscopy. After the electron irradiation, bismuth nanoparticles with a rhombohedral structure and diameter of 6 nm were observed. The average particle size increased with the irradiation time. The electron-induced reduction is attributed to the desorption of oxygen ions. This method offers a one-step route to synthesize bismuth nanoparticles using electron irradiation, and the particle size can be controlled by the irradiation time.

  2. In situ formation of bismuth nanoparticles through electron-beam irradiation in a transmission electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda-Guzman, S; Elizondo-Villarreal, N; Ferrer, D; Torres-Castro, A; Gao, X; Zhou, J P; Jose-Yacaman, M [Chemical Engineering Department and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712 (United States)

    2007-08-22

    In this work, bismuth nanoparticles were synthesized when a precursor, sodium bismuthate, was exposed to an electron beam at room temperature in a transmission electron microscope (TEM). The irradiation effects were investigated in situ using selected-area electron diffraction, high-resolution transmission electron microscopy and x-ray energy dispersive spectroscopy. After the electron irradiation, bismuth nanoparticles with a rhombohedral structure and diameter of 6 nm were observed. The average particle size increased with the irradiation time. The electron-induced reduction is attributed to the desorption of oxygen ions. This method offers a one-step route to synthesize bismuth nanoparticles using electron irradiation, and the particle size can be controlled by the irradiation time.

  3. PtRu/C electrocatalysts prepared using electron beam irradiation

    OpenAIRE

    Dionísio Furtunato da Silva; Almir Oliveira Neto; Eddy Segura Pino; Michele Brandalise; Marcelo Linardi; Estevam Vitorio Spinacé

    2007-01-01

    PtRu/C electrocatalysts (carbon-supported PtRu nanoparticles) were prepared submitting water/ethylene glycol mixtures containing Pt(IV) and Ru(III) ions and the carbon support to electron beam irradiation. The electrocatalysts were characterized by energy dispersive X ray analysis (EDX), X ray diffraction (XRD) and cyclic voltammetry and tested for methanol electro-oxidation aiming fuel cell application. The obtained PtRu/C electrocatalysts showed superior performance for methanol electro-oxi...

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

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Carbon fiber-reinforced advance composites have been used for struetural 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 250kGy. After breakage, the morphology aspect of the tensile specimens prepared with irradiated and non-irradiated carbon fibers were evaluated. SEM micrographs showed modifications on the carbon fiber surface.

  5. Influence of electron beam irradiation on growth of Phytophthora cinnamomi and its control in substrates

    International Nuclear Information System (INIS)

    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.

  6. Formation and microstructural analysis of 3-dimensional titanium oxide structures via large surface electron beam irradiation

    International Nuclear Information System (INIS)

    Recently, in photo electronic devices industry, titanium oxide which was known to have good optical and electrical characteristic's been studied in the microstructural aspect to increase the conversion efficiency, such as making variable architecture, coating the titanium oxide nano-tube with the quantum dots which have higher band gap materials than this, etc. However, the process of making 3-dimensional titanium oxide structure with general deposition system such as hydrothermal growth, CVO, PVD and ALD had more variables and longer time consumption to make nano structures than electron beam irradiation case. Herein, we proceed with making new titanium oxide nano-screen-testing electron beam irradiation. The metal alkoxide composed of the 1 mol of titanium iso-propoxide and the 1 mol of acetylation reacted with water in propylene glycol methyl ether acetate and isopropyl alcohol solvent. After this process which made the bonding among Ti, O and other organics, the polymer solution was deposited on various types of substrate, such as anodized aluminum oxide mail. Kist. ac., Ag nano dots on SiO2 thin film, Au nano dots on SiO2 thin film, etc. The electron beam irradiation was progressed with the vertical accelerator facility of EB tech which was the company in Dijon, Korea The shape, microstructure and chemical composition of the irradiated polymers were characterized using TEM, XRD, Sem and EDS. The three types of Ti-Ox 3-dimensional structure were made; nano dot cluster, spike-like structure and dendrite structure. Each type of these structures was composed of different mircrostructures. Especially, the formation the 3-dimensional structures via electron beam irradiation was not only effected by the electron beam irradiation conditions but also effected by solution concentrate, conductivity and surface energy of substrate

  7. An irradiation facility with a vertical beam for radiobiological studies

    CERN Document Server

    Besserer, J; Dellert, M; Gahn, C; Moosburger, M; Pemler, P; Quicken, P; Distel, L; Schuessler, H

    1999-01-01

    A vertical beam facility for radiobiological experiments was designed and constructed at the Munich Tandem-Accelerator Laboratory. The main part of the facility is a 90 deg. dipole magnet bending the beam of protons or heavy particles into a vertical upward direction, which is advantageous for wet-cell irradiation. After collimation the beam is spread out passively by thin scattering foils and dynamically by magnetic coils. A homogeneity of the radiation field better than +-5% has been achieved over the diameter of the exit window of 60 mm. The dose rate can be widely adjusted from single particles to more than 10 sup 1 sup 0 particles (i.e. hundreds of Grays) per second. The dose measurement is based on single-particle counting and on standard dosimeters. The detector system for dosimetry and irradiation control is described. In a first radiobiological experiment the cell survival of chinese hamster cells was measured after irradiation with 22.7 MeV protons and compared with the X-ray result.

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

    Science.gov (United States)

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

    2016-07-01

    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 (BOD5), and the ratio of BOD5 and COD (BOD5/COD), were compared before and after EB irradiation. During EB irradiation process, color indices and absorbance at 254 nm wavelength (UV254) 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.

  9. Synergistic effect of combination of Irganox 1010 and zinc stearate on thermal stabilization of electron beam irradiated HDPE/EVA both in hot water and oven

    International Nuclear Information System (INIS)

    Thermo-oxidative stability of HDPE/EVA blends can be considerably increased by combination of a high-molecular weight phenolic antioxidant and zinc stearate. In this work, the post-irradiation thermal stability of HDPE/EVA blends has been studied. High-density polyethylene and its blends with ethylene-vinylacetate copolymer in both pure form and mixed with Irganox 1010 and zinc stearate were exposed to electron beam radiation at doses between 80 and 150 kGy, at room temperature, in air. In order to evaluate the thermal stability of the samples, post-irradiation heat treatments were done in both hot water bath at 95 deg. C and in an oven at 140 deg. C. The mechanical properties and changes in the chemical structure were determined during thermal aging in hot water and oven. The gel content was enhanced by increasing EVA concentration in all applied doses. The stabilized blends have lower gel content than the unstabilized samples. From the results of heat aging treatments it was observed that the thermal stability of the unstabilized blend samples was lower than HDPE. Thermal stability of the samples has been improved by incorporation of Irganox 1010 and zinc stearate. Formation of hydroxyl group was insignificant for stabilized samples during heat aging in both conditions. Also, the changes in the value of oxidation induction time (OIT) for the stabilized samples were negligible after prolonged immersion in hot water

  10. Evaluation of fatigue crack behavior in electron beam irradiated polyethylene pipes

    Science.gov (United States)

    Pokharel, Pashupati; Jian, Wei; Choi, Sunwoong

    2016-09-01

    A cracked round bar (CRB) fatigue test was employed to determine the slow crack growth (SCG) behavior of samples from high density polyethylene (HDPE) pipes using PE4710 resin. The structure property relationships of fatigue failure of polyethylene CRB specimens which have undergone various degree of electron beam (EB) irradiation were investigated by observing fatigue failure strength and the corresponding fracture surface morphology. Tensile test of these HDPE specimens showed improvements in modulus and yield strength while the failure strain decreased with increasing EB irradiation. The CRB fatigue test of HDPE pipe showed remarkable effect of EB irradiation on number of cycles to failure. The slopes of the stress-cycles to failure curve were similar for 0-100 kGy; however, significantly higher slope was observed for 500 kGy EB irradiated pipe. Also, the cycle to fatigue failure was seen to decrease as with EB irradiation in the high stress range, ∆σ=(16 MPa to 10.8 MPa); however, 500 kGy EB irradiated samples showed longer cycles to failure than the un-irradiated specimens at the stress range below 9.9 MPa and the corresponding initial stress intensity factor (∆KI,0)=0.712 MPa m1/2. The fracture surface morphology indicated that the cross-linked network in 500 kGy EB irradiated PE pipe can endure low dynamic load more effectively than the parent pipe.

  11. Radiosensitization by PARP inhibition to proton beam irradiation in cancer cells.

    Science.gov (United States)

    Hirai, Takahisa; Saito, Soichiro; Fujimori, Hiroaki; Matsushita, Keiichiro; Nishio, Teiji; Okayasu, Ryuichi; Masutani, Mitsuko

    2016-09-01

    The poly(ADP-ribose) polymerase (PARP)-1 regulates DNA damage responses and promotes base excision repair. PARP inhibitors have been shown to enhance the cytotoxicity of ionizing radiation in various cancer cells and animal models. We have demonstrated that the PARP inhibitor (PARPi) AZD2281 is also an effective radiosensitizer for carbon-ion radiation; thus, we speculated that the PARPi could be applied to a wide therapeutic range of linear energy transfer (LET) radiation as a radiosensitizer. Institutes for biological experiments using proton beam are limited worldwide. This study was performed as a cooperative research at heavy ion medical accelerator in Chiba (HIMAC) in National Institute of Radiological Sciences. HIMAC can generate various ion beams; this enabled us to compare the radiosensitization effect of the PARPi on cells subjected to proton and carbon-ion beams from the same beam line. After physical optimization of proton beam irradiation, the radiosensitization effect of the PARPi was assessed in the human lung cancer cell line, A549, and the pancreatic cancer cell line, MIA PaCa-2. The effect of the PARPi, AZD2281, on radiosensitization to Bragg peak was more significant than that to entrance region. The PARPi increased the number of phosphorylated H2AX (γ-H2AX) foci and enhanced G2/M arrest after proton beam irradiation. This result supports our hypothesis that a PARPi could be applied to a wide therapeutic range of LET radiation by blocking the DNA repair response. PMID:27425251

  12. Experiments and analysis of gold disk targets irradiated by smoothing beams of Xingguang II facilities with 350 nm wavelength

    Institute of Scientific and Technical Information of China (English)

    JIANG; ShaoEn

    2007-01-01

    Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-II) laser facilities with 350 nm wavelength, 0.6 ns pulse width and 20-80 Joules energies. Laser absorption, light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser absorption and scattered light were about 90% and 10%, respectively, under focusing irradiation, but the laser absorption increased 5%-10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of focusing irradiation, the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation; then due to the decrease in laser intensity, X-ray conversion increased. This is highly advantageous to the inertial confinement fusion. However, X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irradiation was basically the same.……

  13. Experiments and analysis of gold disk targets irradiated by smoothing beams of Xingguang II facilities with 350 nm wavelength

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-II) laser facilities with 350 nm wavelength, 0.6 ns pulse width and 20-80 Joules energies. Laser absorption, light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser absorption and scattered light were about 90% and 10%, respectively, under focusing irradiation, but the laser absorption increased 5%-10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of focusing irradiation, the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation; then due to the decrease in laser intensity, X-ray conversion increased. This is highly advantageous to the inertial confinement fusion. However, X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irradiation was basically the same.

  14. In vitro irradiation station for broad beam radiobiological experiments

    Science.gov (United States)

    Wéra, A.-C.; Riquier, H.; Heuskin, A.-C.; Michiels, C.; Lucas, S.

    2011-12-01

    The study of the interaction of charged particles with living matter is of prime importance to the fields of radiotherapy, radioprotection and space radiobiology. Particle accelerators and their associated equipment are proven to be helpful tools in performing basic science in all these fields. Indeed, they can accelerate virtually any ions to a given energy and flux and let them interact with living matter either in vivo or in vitro. In this context, the University of Namur has developed a broad beam in vitro irradiation station for use in radiobiological experiments. Cells are handled in GLP conditions and can be irradiated at various fluxes with ions ranging from hydrogen to carbon. The station is mounted on a 2 MV tandem accelerator, and the energy range can be set up in the linear energy transfer (LET) ranges that are useful for radiobiological experiments. This paper describes the current status of the hardware that has been developed, and presents results related to its performance in term of dose-rate, energy range and beam uniformity for protons, alpha particles and carbon ions. The results of clonogenic assays of A549 lung adenocarcinoma cells irradiated with protons and alpha particles are also presented and compared with literature.

  15. In vitro irradiation station for broad beam radiobiological experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wera, A.-C., E-mail: anne-catharine.wera@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Centre for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP (Belgium); Riquier, H., E-mail: helene.riquier@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Unite de Recherche de Biologie Cellulaire (URBC), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium); Heuskin, A.-C., E-mail: anne-catherine.heuskin@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Centre for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP (Belgium); Michiels, C., E-mail: carine.michiels@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Unite de Recherche de Biologie Cellulaire (URBC), University of Namur-FUNDP, Rue de Bruxelles, 61, B-5000 Namur (Belgium); Lucas, S., E-mail: stephane.lucas@fundp.ac.be [NAmur Research Institute for LIfe Sciences (NARILIS), Research Centre for the Physics of Matter and Radiation (PMR), University of Namur-FUNDP (Belgium)

    2011-12-15

    The study of the interaction of charged particles with living matter is of prime importance to the fields of radiotherapy, radioprotection and space radiobiology. Particle accelerators and their associated equipment are proven to be helpful tools in performing basic science in all these fields. Indeed, they can accelerate virtually any ions to a given energy and flux and let them interact with living matter either in vivo or in vitro. In this context, the University of Namur has developed a broad beam in vitro irradiation station for use in radiobiological experiments. Cells are handled in GLP conditions and can be irradiated at various fluxes with ions ranging from hydrogen to carbon. The station is mounted on a 2 MV tandem accelerator, and the energy range can be set up in the linear energy transfer (LET) ranges that are useful for radiobiological experiments. This paper describes the current status of the hardware that has been developed, and presents results related to its performance in term of dose-rate, energy range and beam uniformity for protons, alpha particles and carbon ions. The results of clonogenic assays of A549 lung adenocarcinoma cells irradiated with protons and alpha particles are also presented and compared with literature.

  16. Study of the electron beam irradiation effect on some properties of aromatic aliphatic copolyester films; Estudo do efeito da radiacao por feixe de eletrons nas propriedades de filmes de copoliester alifatico aromatico

    Energy Technology Data Exchange (ETDEWEB)

    Poveda, Patricia Negrini Siqueira

    2008-07-01

    Biodegradable and green plastics are the new tendency in the world. The effect of the electron beam irradiation in aromatic aliphatic copolyester and the blend with corn starch films (Ecoflex{sup R} and Ecobras{sup R}) were studied by tensile strength at break, elongation at break, Scanning Electronic Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), crosslinking degree and biodegradability. The measurements in both, the machine direction and the transverse direction were made for mechanical tests. It was found that, the electron irradiation caused an increase in the strength at break of the blend with corn starch film, when doses of up to 10 kGy were applied. A significant decrease of the elongation at break of the blend with corn starch was observed at doses of 10 kGy and 40 kGy. It was not found important change in tensile properties for aromatic aliphatic copolyester. Structural changes of the samples (crosslinking or degradation) by SEM were not observed. The FT-IR identified the characteristic peaks of each involved functional group (copolyester and corn starch). However, it was not found bands of oxidation of the samples. In the DSC, changes in the melting temperature of the irradiated Ecoflex{sup R} and Ecobras{sup R} samples, was not identified when compared with the samples of reference. However, it was verified a reduction in the melting enthalpy of the Ecobras{sup R} samples after irradiation. The Ecobras{sup R} material presented crosslinking, when submitted to doses of 10 kGy and 40 kGy. The Ecoflex{sup R} material did not present crosslinking when submitted to these doses. The biodegradability of the materials was evaluated by two methods of test: soil simulated and enzymatic. In both methods, the irradiated samples presented faster biodegradation than the references not irradiated. (author)

  17. Electron beam irradiation of Matricaria chamomilla L. for microbial decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Nemtanu, Monica R. [National Institute for Lasers, Plasma and Radiation Physics, Electron Accelerator Laboratory, 409 Atomistilor Street, P.O. Box MG-36, 077125 Bucharest-Magurele (Romania)], E-mail: monica.nemtanu@inflpr.ro; Kikuchi, Irene Satiko; Jesus Andreoli Pinto, Terezinha de [University of Sao Paulo, Faculty of Pharmaceutical Sciences, Department of Pharmacy, Av. Prof. Lineu Prestes, 580-Bloco 13, Cidade Universitaria, 05508-900 Sao Paulo (Brazil); Mazilu, Elena; Setnic, Silvia [S.C. Hofigal Export-Import S.A., 2A Intrarea Serelor Street, 75669, Bucharest 4 (Romania); Bucur, Marcela [University of Bucharest, Faculty of Biology, Department of Microbiology, 1-3 Aleea Portocalelor Street, Bucharest 6 (Romania); Duliu, Octavian G. [University of Bucharest, Department of Atomic and Nuclear Physics, P.O. Box MG-11, 077125 Bucharest (Romania); Meltzer, Viorica; Pincu, Elena [University of Bucharest, Faculty of Chemistry, Department of Physical Chemistry, Bd. Regina Elisabeta 4-12, 030018 Bucharest (Romania)

    2008-05-15

    Wild chamomile (Matricaria chamomilla L.) is one of the most popular herbal materials with both internal and external use to cure different health disturbances. As a consequence of its origin, chamomile could carry various microbial contaminants which offer different hazards to the final consumer. Reduction of the microbial load to the in force regulation limits represents an important phase in the technological process of vegetal materials, and the electron beam treatment might be an efficient alternative to the classical methods of hygienic quality assurance. The purpose of the study was to analyze the potential application of the electron beam treatment in order to assure the microbial safety of the wild chamomile. Samples of chamomile dry inflorescences were treated in electron beam (e-beam) of 6 MeV mean energy, at room temperature and ambient pressure. Some loss of the chemical compounds with bioactive role could be noticed, but the number of microorganisms decreased as a function on the absorbed dose. Consequently, the microbial quality of studied vegetal material inflorescences was improved by e-beam irradiation.

  18. 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.

  19. DNA damage response signaling in lung adenocarcinoma A549 cells following gamma and carbon beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Somnath [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Narang, Himanshi, E-mail: himinarang@gmail.com [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Sarma, Asitikantha [Radiation Biology Laboratory, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067 (India); Krishna, Malini [Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2011-11-01

    Carbon beams (5.16 MeV/u, LET = 290 keV/{mu}m) are high linear energy transfer (LET) radiation characterized by higher relative biological effectiveness than low LET radiation. The aim of the current study was to determine the signaling differences between {gamma}-rays and carbon ion-irradiation. A549 cells were irradiated with 1 Gy carbon or {gamma}-rays. Carbon beam was found to be three times more cytotoxic than {gamma}-rays despite the fact that the numbers of {gamma}-H2AX foci were same. Percentage of cells showing ATM/ATR foci were more with {gamma}-rays however number of foci per cell were more in case of carbon irradiation. Large BRCA1 foci were found in all carbon irradiated cells unlike {gamma}-rays irradiated cells and prosurvival ERK pathway was activated after {gamma}-rays irradiation but not carbon. The noteworthy finding of this study is the early phase apoptosis induction by carbon ions. In the present study in A549 lung adenocarcinoma, authors conclude that despite activation of same repair molecules such as ATM and BRCA1, differences in low and high LET damage responses might be due to their distinct macromolecular complexes rather than their individual activation and the activation of cytoplasmic pathways such as ERK, whether it applies to all the cell lines need to be further explored.

  20. Measuring Broadband IR Irradiance in the Direct Solar Beam (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Reda, I.

    2015-03-01

    Solar and atmospheric science radiometers, e.g. pyranometers, pyrheliometers, and photovoltaic cells are calibrated with traceability to a consensus reference, which is maintained by Absolute Cavity Radiometers (ACRs). The ACR is an open cavity with no window, developed to measure extended broadband direct solar irradiance beyond the ultraviolet and infrared bands below and above 0.2 um and 50 um, respectively. On the other hand, pyranometers and pyrheliometers are developed to measure broadband shortwave irradiance from approximately 0.3 um to 3 um, while the present photovoltaic cells are limited to approximately 0.3 um to 1 um. The broadband mismatch of ACR versus such radiometers causes discrepancy in radiometers' calibration methods that has not been discussed or addressed in the solar and atmospheric science literature. Pyrgeometers are also used for solar and atmospheric science applications and are calibrated with traceability to consensus reference, yet are calibrated during nighttime only, because no consensus reference has yet been established for the daytime longwave irradiance. This poster shows a method to measure the broadband IR irradiance in the direct solar beam from 3 um to 50 um, as a first step that might be used to help develop calibration methods to address the mismatch between broadband ACR and shortwave radiometers, and the lack of a daytime reference for pyrgeometers. The irradiance was measured from sunrise to sunset for 5 days when the sun disk was cloudless; the irradiance varied from approximately 1 Wm-2 to 16 Wm-2 for solar zenith angle from 80 degrees to 16 degrees respectively; estimated uncertainty is 1.5 Wm-2.

  1. Measuring Broadband IR Irradiance in the Direct Solar Beam (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Reda, I.; Konings, J.; Xie, Y.; Dooraghi, M.; Sengupta, M.

    2015-03-01

    Solar and atmospheric science radiometers, e.g. pyranometers, pyrheliometers, and photovoltaic cells are calibrated with traceability to a consensus reference, which is maintained by Absolute Cavity Radiometers (ACRs). The ACR is an open cavity with no window, developed to measure extended broadband direct solar irradiance beyond the ultraviolet and infrared bands below and above 0.2 micrometers and 50 micrometers, respectively. On the other hand, pyranometers and pyrheliometers are developed to measure broadband shortwave irradiance from approximately 0.3 micrometers to 3 micrcometers, while the present photovoltaic cells are limited to approximately 0.3 micrometers to 1 micrometers. The broadband mismatch of ACR versus such radiometers causes discrepancy in radiometers' calibration methods that has not been discussed or addressed in the solar and atmospheric science literature. Pyrgeometers are also used for solar and atmospheric science applications and calibrated with traceability to consensus reference, yet calibrated during nighttime only, because no consensus reference has yet been established for the daytime longwave irradiance. This poster shows a method to measure the broadband IR irradiance in the direct solar beam from 3 micrometers to 50 micrometers, as first step that might be used to help develop calibration methods to address the mismatch between broadband ACR and shortwave radiometers, and the lack of a daytime reference for pyrgeometers. The irradiance was measured from sunrise to sunset for 5 days when the sun disk was cloudless; the irradiance varied from approximately 1 Wm-2 to 16 Wm-2 for solar zenith angle from 80 degres to 16 degrees respectively; estimated uncertainty is 1.5 Wm-2.

  2. Distribution of products in polymer materials induced by ion-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, Masaki; Kudoh, Hisaaki; Sasuga, Tsuneo; Seguchi, Tadao [Japan Atomic Energy Research Inst., Tokyo (Japan); Hama, Yoshimasa; Hamanaka, Ken-ichi; Matsumoto, Hideya

    1997-03-01

    The depth profile of double bond formed in low density polyethylene (LDPE) sheet by ion beams irradiation was observed by a micro FT-IR spectrometer in order to investigate the linear energy transfer (LET) dependency on radiation effects to polymer materials. The distribution of double bond formation in LDPE by irradiation of light ions as H+ was found to be same with the dose distribution calculated from TRIM code, and the yield was also same with that by gamma-rays irradiation, which means that the LET dependency is very small. However, the distribution of double bond to depth was much different from the calculated depth-dose in heavy ions irradiation as Ar and Kr. Then, the dose evaluation was difficult from the TRIM code calculation for heavy ions. (author)

  3. The influence of electron beam irradiation on the chemical and structural properties of medical grade Polyurethane

    CERN Document Server

    Shin, Sukyoung

    2015-01-01

    Thermo plastic polyurethane (TPU) provides excellent bio-compatibility, flexibility and good irradiation resistance; however, extremely high irradiation doses can alter the structure and function of macromolecules, resulting in oxidation, chain scission and cross-linking. In this study, the effects of e-beam irradiation on the medical grade thermo plastic polyurethane were studied. The changes in the chain length and their distribution as well as the changes in molecular structure were studied. The GPC (Gel Permeation Chromatography) results show that the oxidative decomposition is followed by a decrease in molecular mass together with an increase in polydispersity. This indicates a very inhomogeneous degradation, which is a consequence of the specific course and of the intensity of oxidative degradation. This was confirmed by means of mechanical property measurements. Overall, this study demonstrated that the medical grade TPU was affected by radiation exposure, particularly at high irradiation doses.

  4. Proton irradiation damage of an annealed Alloy 718 beam window

    Science.gov (United States)

    Bach, H. T.; Anderoglu, O.; Saleh, T. A.; Romero, T. J.; Kelsey, C. T.; Olivas, E. R.; Sencer, B. H.; Dickerson, P. O.; Connors, M. A.; John, K. D.; Maloy, S. A.

    2015-04-01

    Mechanical testing and microstructural analysis was performed on an Alloy 718 window that was in use at the Los Alamos Neutron Science Center (LANSCE) Isotope Production Facility (IPF) for approximately 5 years. It was replaced as part of the IPF preventive maintenance program. The window was transported to the Wing 9 hot cells at the Chemical and Metallurgical Research (CMR) LANL facility, visually inspected and 3-mm diameter samples were trepanned from the window for mechanical testing and microstructural analysis. Shear punch testing and optical metallography was performed at the CMR hot cells. The 1-mm diameter shear punch disks were cut into smaller samples to further reduce radiation exposure dose rate using Focus Ion Beam (FIB) and microstructure changes were analyzed using a Transmission Electron Microscopy (TEM). Irradiation doses were determined to be ∼0.2-0.7 dpa (edge) to 11.3 dpa (peak of beam intensity) using autoradiography and MCNPX calculations. The corresponding irradiation temperatures were calculated to be ∼34-120 °C with short excursion to be ∼47-220 °C using ANSYS. Mechanical properties and microstructure analysis results with respect to calculated dpa and temperatures show that significant work hardening occurs but useful ductility still remains. The hardening in the lowest dose region (∼0.2-0.7 dpa) was the highest and attributed to the formation of γ″ precipitates and irradiation defect clusters/bubbles whereas the hardening in the highest dose region (∼11.3 dpa) was lower and attributed mainly to irradiation defect clusters and some thermal annealing.

  5. EELS study on BST thin film under electron beam irradiation

    Institute of Scientific and Technical Information of China (English)

    RAO Jie; ZHU Jing

    2004-01-01

    It was found that BST thin film was damaged by the irradiation of high density electron beam (the current density was about 2 nA/cm2). In-situ and real time EELS showed that the intensity ratio of Ti to O edge and the distance between Ti and O edge changed. It indicated that the film lost oxygen and thus the oxidation states of positive ions lowered. EELS study with high spatial resolution proved that compared with the inner of columnar grains, the grain boundaries with special structure and chemical environment were the main passageway of oxygen loss.

  6. PtRu/C electrocatalysts prepared using electron beam irradiation

    Directory of Open Access Journals (Sweden)

    Dionísio Furtunato da Silva

    2007-12-01

    Full Text Available PtRu/C electrocatalysts (carbon-supported PtRu nanoparticles were prepared submitting water/ethylene glycol mixtures containing Pt(IV and Ru(III ions and the carbon support to electron beam irradiation. The electrocatalysts were characterized by energy dispersive X ray analysis (EDX, X ray diffraction (XRD and cyclic voltammetry and tested for methanol electro-oxidation aiming fuel cell application. The obtained PtRu/C electrocatalysts showed superior performance for methanol electro-oxidation at room temperature compared to commercial PtRu/C electrocatalyst.

  7. Electron beam irradiation for biological decontamination of Spirulina platensis

    Energy Technology Data Exchange (ETDEWEB)

    Brasoveanu, Mirela [National Institute for Lasers, Plasma and Radiation Physics, Department of Electron Accelerators, 409 Atomistilor Street, P.O. Box MG-36, RO 76 900 Bucharest-Magurele (Romania)]. E-mail: mirela@infim.ro; Nemtanu, Monica [National Institute for Lasers, Plasma and Radiation Physics, Department of Electron Accelerators, 409 Atomistilor Street, P.O. Box MG-36, RO 76 900 Bucharest-Magurele (Romania); Minea, R. [National Institute for Lasers, Plasma and Radiation Physics, Department of Electron Accelerators, 409 Atomistilor Street, P.O. Box MG-36, RO 76 900 Bucharest-Magurele (Romania); Grecu, Maria Nicoleta [National Institute for Materials Physics, Bucharest-Magurele (Romania); Mazilu, Elena [Hofigal SA (Romania); Radulescu, Nora [Hofigal SA (Romania)

    2005-10-15

    The Cyanobacterium Spirulina is commercialized for its use in health foods and for therapeutic purposes due to its valuable constituents particularly proteins and vitamins. The aim of the paper is to study the Spirulina platensis behaviour when it is electron beam irradiated for biological decontamination. Microbial load, antioxidant activity, enzymatic inhibition, electron spin resonance (ESR) and UV-Vis spectra were measured for doses up to 80 kGy. The results were correlated with doses in order to find where decontamination is efficient, keeping the Spirulina qualities.

  8. Nanostructure fabrication using electron beam irradiation of organometallic compounds

    CERN Document Server

    Bedson, T R

    2001-01-01

    Nanoelectronics- the quest to fabricate quantum devices- is the motivation for this thesis. The place of nanolithography is discussed amongst conventional microfabrication methods, together with the materials currently employed in lithography. The experimental methods, equipment and new resist materials (films of nanoparticles) are then explored in the work described. A summary of the results obtained by the research is presented, followed by the detailed results in the form of a series of published and submitted papers. A systematic study of the response of ferrocene adsorbed onto graphite at 160K to low energy electron beams, that results in varying behaviour depending on the energy of irradiation, is first described. Following are studies of the characteristics of passivated gold nanoclusters when used as a monolayer negative tone resist in direct electron beam writing. Fabrication of lines with widths as narrow as 26 nm has been achieved. Measurements of the linewidth as a function of electron dose allow ...

  9. Study of albumin adsorption on ion beam irradiated polymer surfaces

    International Nuclear Information System (INIS)

    The process of adsorption of human serum albumin has been studied for poly-hydroxy-methylsiloxane and poly-ethylene-terephtalate surfaces modified by 5 keV Ar+ irradiation. The adsorption kinetics of albumin has been investigated as a function of the modifications induced by irradiation of the two polymer surfaces. Fluorescence spectroscopy, X-ray photoelectron spectroscopy and contact angle technique, respectively, have been used to determine the adsorption kinetics and to characterize the chemical composition and the surface free energy of the irradiated surfaces. Two basic classes of adsorption kinetics were found in connection with two different adsorption mechanisms. The irradiation-induced effects have been seen to be able to change the type of the adsorption process from one class to the other one as a function of the total surface free energy modification

  10. Carbon-ion beam irradiation kills X-ray-resistant p53-null cancer cells by inducing mitotic catastrophe.

    Directory of Open Access Journals (Sweden)

    Napapat Amornwichet

    Full Text Available BACKGROUND AND PURPOSE: To understand the mechanisms involved in the strong killing effect of carbon-ion beam irradiation on cancer cells with TP53 tumor suppressor gene deficiencies. MATERIALS AND METHODS: DNA damage responses after carbon-ion beam or X-ray irradiation in isogenic HCT116 colorectal cancer cell lines with and without TP53 (p53+/+ and p53-/-, respectively were analyzed as follows: cell survival by clonogenic assay, cell death modes by morphologic observation of DAPI-stained nuclei, DNA double-strand breaks (DSBs by immunostaining of phosphorylated H2AX (γH2AX, and cell cycle by flow cytometry and immunostaining of Ser10-phosphorylated histone H3. RESULTS: The p53-/- cells were more resistant than the p53+/+ cells to X-ray irradiation, while the sensitivities of the p53+/+ and p53-/- cells to carbon-ion beam irradiation were comparable. X-ray and carbon-ion beam irradiations predominantly induced apoptosis of the p53+/+ cells but not the p53-/- cells. In the p53-/- cells, carbon-ion beam irradiation, but not X-ray irradiation, markedly induced mitotic catastrophe that was associated with premature mitotic entry with harboring long-retained DSBs at 24 h post-irradiation. CONCLUSIONS: Efficient induction of mitotic catastrophe in apoptosis-resistant p53-deficient cells implies a strong cancer cell-killing effect of carbon-ion beam irradiation that is independent of the p53 status, suggesting its biological advantage over X-ray treatment.

  11. Cell adhesion behavior on the silicone rubber surface modified by using ion beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, In Tae; Jung, Chan Hee; Nh, Young Chang; Choi, Jae Hak [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kuk, In Seol [Hanyang University, Seoul (Korea, Republic of); An, Mi Young [Chungnam National University, Daejeon (Korea, Republic of)

    2009-12-15

    In this study we studied cell adhesion and proliferation on the surface of a silicone rubber modified by ion beam irradiation. The surface property of the irradiated silicone rubber was characterized by water contact angle and FT-IR analyses. It was observed that human (HEK293) fibroblast cells exhibit strong adhesion to the irradiated silicone surface. This enhanced adhesion of mammalian cells can be attributed to the increase in the hydrophilicity of the silicone surface by ion beam irradiation.

  12. Ion irradiation effects on metallic nanocrystals

    Science.gov (United States)

    Kluth, P.; Johannessen, B.; Giulian, R.; Schnohr, C. S.; Foran, G. J.; Cookson, D. J.; Byrne, A. P.; Ridgway, M. C.

    We have investigated structural and morphological properties of metallic nanocrystals (NCs) exposed to ion irradiation. NCs were characterized by transmission electron microscopy in combination with advanced synchrotron-based analytical techniques, in particular X-ray absorption spectroscopy and small-angle X-ray scattering. A number of different effects were observed depending on the irradiation conditions. At energies where nuclear stopping is predominant, structural disorder/amorphization followed by inverse Ostwald ripening/dissolution due to ion beam mixing was observed for Au and Cu NCs embedded in SiO2. The ion-irradiation-induced crystalline to amorphous transition in the NCs, which cannot be achieved in the corresponding bulk metals, was attributed to their initially higher structural energy as compared to bulk material and possibly preferential nucleation of the amorphous phase at the NC/SiO2 interface. At very high irradiation energies (swift heavy ion irradiation), where the energy loss is nearly entirely due to electronic stopping, a size-dependent shape transformation of the NCs from spheres to rod like shapes was apparent in Au NCs. Our preliminary results are in good agreement with considerations on melting of the NCs in the ion track as one mechanism involved in the shape transformation.

  13. Comparison of Quality of Bologna Sausage Manufactured by Electron Beam or X-Ray Irradiated Ground Pork.

    Science.gov (United States)

    Shin, Mee-Hye; Lee, Ju-Woon; Yoon, Young-Min; Kim, Jong Heon; Moon, Byeong-Geum; Kim, Jae-Hun; Song, Beom-Suk

    2014-01-01

    Ground lean pork was irradiated by an electron beam or X-rays to compare the effects of two types of radiation generated by a linear accelerator on the quality of Bologna sausage as a model meat product. Raw ground lean pork was vacuum packaged at a thickness of 1.5 cm and irradiated at doses of 2, 4, 6, 8, or 10 kGy by an electron beam (2.5 MeV) or X-rays (5 MeV). Solubility of myofibrillar proteins, bacterial counts, and thiobarbituric acid reactive substance (TBARS) values were determined for raw meat samples. Bologna sausage was manufactured using the irradiated lean pork, and total bacterial counts, TBARS values, and quality properties (color differences, cooking yield, texture, and palatability) were determined. Irradiation increased the solubility of myofibrillar proteins in a dose-dependent manner (p<0.05). Bacterial contamination of the raw meat was reduced as the absorbed dose increased, and the reduction was the same for both radiation types. Differences were observed only between irradiated and non-irradiated samples (p<0.05). X-ray irradiation may serve as an alternative to gamma irradiation and electron beam irradiation.

  14. Wood Sawdust/Natural Rubber Ecocomposites Cross-Linked by Electron Beam Irradiation

    Directory of Open Access Journals (Sweden)

    Elena Manaila

    2016-06-01

    Full Text Available The obtaining and characterization of some polymeric eco-composites based on wood sawdust and natural rubber is presented. The natural rubber was cross-linked using the electron beam irradiation. The irradiation doses were of 75, 150, 300 and 600 kGy and the concentrations of wood sawdust were of 10 and 20 phr, respectively. As a result of wood sawdust adding, the physical and mechanical properties such as hardness, modulus at 100% elongation and tensile strength, showed significant improvements. The presence of wood sawdust fibers has a reinforcing effect on natural rubber, similar or better than of mineral fillers. An increase in the irradiation dose leads to the increasing of cross-link density, which is reflected in the improvement of hardness, modulus at 100% elongation and tensile strength of blends. The cross-linking rates, appreciated using the Flory-Rehner equation, have increased with the amount of wood sawdust in blends and with the irradiation dose. Even if the gel fraction values have varied irregularly with the amount of wood sawdust and irradiation dose it was over 90% for all blends, except for the samples without wood sawdust irradiated with 75 kGy. The water uptake increased with increasing of fiber content and decreased with the irradiation dose.

  15. Theoretical study of the effect of the size of a high-energy proton beam of the Large Hadron Collider on the formation and propagation of shock waves in copper irradiated by 450-GeV proton beams

    Science.gov (United States)

    Ryazanov, A. I.; Stepakov, A. V.; Vasilyev, Ya. S.; Ferrari, A.

    2014-02-01

    The interaction of 450-GeV protons with copper, which is the material of the collimators of the Large Hadron Collider, has been theoretically studied. A theoretical model for the formation and propagation of shock waves has been proposed on the basis of the analysis of the energy released by a proton beam in the electronic subsystem of the material owing to the deceleration of secondary particles appearing in nuclear reactions induced by this beam on the electronic subsystem of the material. The subsequent transfer of the energy from the excited electronic subsystem to the crystal lattice through the electron-phonon interaction has been described within the thermal spike model [I.M. Lifshitz, M.I. Kaganov, and L.V. Tanatarov, Sov. Phys. JETP 4, 173 (1957); I.M. Lifshitz, M.I. Kaganov, and L.V. Tanatarov, At. Energ. 6, 391 (1959); K. Yasui, Nucl. Instrum. Methods Phys. Res., Sect. B 90, 409 (1994)]. The model of the formation of shock waves involves energy exchange processes between excited electronic and ionic subsystems of the irradiated material and is based on the hydrodynamic approximation proposed by Zel'dovich [Ya.B. Zel'dovich and Yu.P. Raizer, Physics of Shock Waves and High-Temperature Hydrodynamic Phenomena (Nauka, Moscow, 1966; Dover, New York, 2002)]. This model makes it possible to obtain the space-time distributions of the main physical characteristics (temperatures of the ionic and electronic subsystems, density, pressure, etc.) in materials irradiated by high-energy proton beams and to analyze the formation and propagation of shock waves in them. The nonlinear differential equations describing the conservation laws of mass, energy, and momentum of electrons and ions in the Euler variables in the case of the propagation of shock waves has been solved with the Godunov scheme [S. K. Godunov, A.V. Zabrodin, M.Ya. Ivanov, A.N. Kraiko, and G.P. Prokopov, Numerical Solution of Multidimensional Problems in Gas Dynamics (Nauka, Moscow, 1976) [in Russian

  16. Target and structural materials under dual-beam irradiation

    International Nuclear Information System (INIS)

    The European Spallation Source (ESS) is planned to have a beam power of 5 MW (3.75 mA of 1.334 GeV protons). This is by a factor 30 higher than the available most powerful spallation source ISIS at Rutherford-Appleton Lab. (RAL) in Great-Britain. This causes a damage rate of approx. 10 dpa (displacements per atom) per month in target materials (W or Ta) or structural materials. The problem of radiation damage by high energy protons in different alloys has been recently reviewed. At HMI, simulation irradiation using heavy ions and helium or hydrogen ions at the dual-beam facility are being out. Here, we report on some preliminary results obtained on tantalum as target material and on ferritic/martensitic steels (HT9 type steels or comparable steels), which are proposed to be used as structural materials. Goal of these investigations is to correlate the results with those obtained at spallation irradiated specimens and to investigate the unexplored field of simultaneous production of damage, helium and hydrogen at high levels. (author) 4 figs., 1 tab., 9 refs

  17. A case of mycosis fungoides treated with total skin electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Maruta, Tsutomu; Murakami, Masao; Kuroda, Yasumasa (Tenri Hospital, Nara (Japan)) (and others)

    1992-02-01

    Reported is the case of a 52-year-old woman with mycosis fungiodes (T{sub 3}N{sub 3}B{sub 0}M{sub 0}, stage IV-A) who was treated with total skin electron beam irradiation (TSEI). The patient was irradiated with 2 Gy per fraction up to 20 Gy totally for 8 weeks. The authors used their own method: 3 overlapping beams (SSD: 145 cm) in a four-field technique with 4 MeV electrons. After delivering 10 Gy, skin nodules disappeared and were replaced by pigmentation. During the treatment, which included systemic chemo- and PUVA-therapy, no serious side effects were noted. Therefore, although a multidisciplinary therapy is basically required for an advanced stage of this condition, TSEI was found to be the most effective in this case. (author).

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

    International Nuclear Information System (INIS)

    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

  19. Enhanced electromagnetic properties of nickel nanoparticiles dispersed carbon fiber via electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yeong Ju; Kim, Hyun Bin; Lee, Seung Jun; Kang, Phil Hyun [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2015-02-15

    Carbon fiber has received much attention owing to its properties, including a large surface-to-volume ratio, chemical and thermal stability, high thermal and electrical conductivity, and high mechanical strengths. In particular, magnetic nanopowder dispersed carbon fiber has been attractive in technological applications such as the electrochemical capacitor and electromagnetic wave shielding. In this study, the nickel-oxide-nanoparticle dispersed polyacrylonitrile (PAN) fibers were prepared through an electrospinning method. Electron beam irradiation was carried out with a 2.5 MeV beam energy to stabilize the materials. The samples were then heat treated for stabilization and carbonization. The nanofiber surface was analyzed using a field emission scanning electron microscope (FE-SEM). The crystal structures of the carbon matrix and nickel nanopowders were analysed using X-ray diffraction (XRD). In addition, the magnetic and electrical properties were analyzed using a vibrating sample magnetometer (VSM) and 4 point probe. As the irradiation dose increases, the density of the carbon fiber was increased. In addition, the electrical properties of the carbon fiber improved through electron beam irradiation. This is because the amorphous region of the carbon fiber decreases. This electron beam effect of PAN fibers containing nickel nanoparticles confirmed their potential as a high performance carbon material for various applications.

  20. Investigation of heat release in the targets during irradiation by ion beams

    CERN Document Server

    Dalkarov, O D; Rusetskii, A S

    2015-01-01

    The DD-reaction is investigated and the heat emission off the targets during their irradiation with ion beams is studied at the HELIS ion accelerator at LPI. The heat emission is observed to be significantly higher in the case of irradiation of the Ti/TiO2:Dx-targets by a D+ beam, as compared to the H+ and Ne+ beams. Furthermore, it depends on the concentration of deuterium in the target and current density of the deuteron beam.

  1. Exquisite wild mushrooms as a source of dietary fiber: analysis in electron-beam irradiated samples

    OpenAIRE

    Fernandes, Ângela; João C. M. Barreira; Antonio, Amilcar L.; Morales, Patricia; Férnandez-Ruiz, Virginia; Martins, Anabela; Oliveira, M.B.P.P.; Ferreira, Isabel C. F. R.

    2015-01-01

    In the present study, electron-beam irradiation was applied to dried samples of Boletus edulis and Macrolepiota procera to evaluate the effects on their fiber composition. Both species presented an important percentage of dietary fiber, soluble and insoluble in different ratios. These high fiber levels are an interesting feature, allowing considering mushrooms as an alternative source of dietary fibers in the highly competitive market of fiber-enriched food products. In B. edulis samples, ins...

  2. Spectroscopic and thermal studies of 8 MeV electron beam irradiated HPMC films

    Energy Technology Data Exchange (ETDEWEB)

    Sangappa [Department of Studies in Physics, Mangalore University, Mangalagangotri 574 199 (India)], E-mail: syhalabhavi@yahoo.co.in; Asha, S. [Department of Studies in Physics, Mangalore University, Mangalagangotri 574 199 (India); Demappa, T. [Department of Studies in Polymer Science, University of Mysore, Sir M.V.P.G. Center, Mandya 571 402 (India); Sanjeev, Ganesh [Microtron Centre, Mangalore University, Mangalagangotri 574 199 (India); Parameswara, P.; Somashekar, R. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006 (India)

    2009-07-01

    Radiation-induced changes in hydroxypropyl methylcellulose (HPMC) films under electron irradiation were investigated and correlated with dose. Polymer samples were irradiated in air at room temperature by an electron beam accelerator in the range of 0-100 kGy. Various properties of the irradiated films were studied using a Ultraviolet-Visible spectrophotometer and Fourier transform infrared spectroscopy and thermogravimetric analysis. Electron irradiation was found to induce changes in the physical, chemical and thermal properties, depending on the irradiation dose.

  3. Irradiation effects in glasses

    International Nuclear Information System (INIS)

    The deposition of irradiation energy can alter the physical properties of glasses through bond-breaking (energetic photons; fast particles) and atomic displacements (Coulombic and collisional: n0, e, ions). These processes can alter UV-visible optical properties via electron-hole trapping and IR-spectra as a result of network damage. The movement of network atoms results in volume dilatation which change the hardness, refractive index, and dissolution rates. All of these changes can be realized with ion implantation and, in addition, implantation of chemically active species can lead to compound formation in the implanted regions. For this reason, emphasis will be placed on the implantation-induced surface modifications of glasses (mostly silicates). The paper includes crystallization, surface stress, refractive index changes and optoelectronic application and chemical reactivity

  4. New green polymeric composites based on hemp and natural rubber processed by electron beam irradiation.

    Science.gov (United States)

    Stelescu, Maria-Daniela; Manaila, Elena; Craciun, Gabriela; Dumitrascu, Maria

    2014-01-01

    A new polymeric composite based on natural rubber reinforced with hemp has been processed by electron beam irradiation and characterized by several methods. The mechanical characteristics: gel fraction, crosslink density, water uptake, swelling parameters, and FTIR of natural rubber/hemp fiber composites have been investigated as a function of the hemp content and absorbed dose. Physical and mechanical properties present a significant improvement as a result of adding hemp fibres in blends. Our experiments showed that the hemp fibers have a reinforcing effect on natural rubber similar to mineral fillers (chalk, carbon black, silica). The crosslinking rates of samples, measured using the Flory-Rehner equation, increase as a result of the amount of hemp in blends and the electron beam irradiation dose increasing. The swelling parameters of samples significantly depend on the amount of hemp in blends, because the latter have hydrophilic characteristics.

  5. New Green Polymeric Composites Based on Hemp and Natural Rubber Processed by Electron Beam Irradiation

    Directory of Open Access Journals (Sweden)

    Maria-Daniela Stelescu

    2014-01-01

    Full Text Available A new polymeric composite based on natural rubber reinforced with hemp has been processed by electron beam irradiation and characterized by several methods. The mechanical characteristics: gel fraction, crosslink density, water uptake, swelling parameters, and FTIR of natural rubber/hemp fiber composites have been investigated as a function of the hemp content and absorbed dose. Physical and mechanical properties present a significant improvement as a result of adding hemp fibres in blends. Our experiments showed that the hemp fibers have a reinforcing effect on natural rubber similar to mineral fillers (chalk, carbon black, silica. The crosslinking rates of samples, measured using the Flory-Rehner equation, increase as a result of the amount of hemp in blends and the electron beam irradiation dose increasing. The swelling parameters of samples significantly depend on the amount of hemp in blends, because the latter have hydrophilic characteristics.

  6. Designed-seamless irradiation technique for extended whole mediastinal proton-beam irradiation for esophageal cancer

    Directory of Open Access Journals (Sweden)

    Okonogi Noriyuki

    2012-10-01

    Full Text Available Abstract Background Proton-beam therapy (PBT provides therapeutic advantages over conformal x-ray therapy in sparing organs at risk when treating esophageal cancer because of the fundamental physical dose distribution of the proton-beam. However, cases with extended esophageal lesions are difficult to treat with conventional PBT with a single isocentric field, as the length of the planning target volume (PTV is longer than the available PBT field size in many facilities. In this study, the feasibility of a practical technique to effectively match PBT fields for esophageal cancer with a larger regional field beyond the available PBT field size was investigated. Methods Twenty esophageal cancer patients with a larger regional field than the available PBT single-field size (15 cm in our facility were analyzed. The PTV was divided into two sections to be covered by a single PBT field. Subsequently, each PTV isocenter was aligned in a cranial-caudal (CC axis to rule out any influence by the movement of the treatment couch in anterior-posterior and left-right directions. To obtain the appropriate dose distributions, a designed-seamless irradiation technique (D-SLIT was proposed. This technique requires the following two adjustments: (A blocking a part of the PTV by multi-leaf collimator(s (MLCs; and (B fine-tuning the isocenter distance by the half-width of the MLC leaf (2.5 mm in our facility. After these steps, the inferior border of the cranial field was designed to match the superior border of the caudal field. Dose distributions along the CC axis around the field junction were evaluated by the treatment-planning system. Dose profiles were validated with imaging plates in all cases. Results The average and standard deviation of minimum dose, maximum dose, and dose range between maximum and minimum doses around the field junction by the treatment-planning system were 95.9 ± 3.2%, 105.3 ± 4.1%, and 9.4 ± 5.2%. The dose profile validated by the

  7. Microstructural, thermal and antibacterial properties of electron beam irradiated Bombyx mori silk fibroin films

    Energy Technology Data Exchange (ETDEWEB)

    Asha, S.; Sanjeev, Ganesh, E-mail: ganeshsanjeev@rediffmail.com [Microtron Center, Department of Studies in Physics, Mangalore University, Mangalagangotri - 574199 (India); Sangappa [Department of Studies in Physics, Mangalore University, Mangalagangotri - 574199 (India); Naik, Prashantha; Chandra, K. Sharat [Department of Biosciences, Mangalore University, Mangalagangotri - 574199 (India)

    2014-04-24

    The Bombyx mori silk fibroin (SF) films were prepared by solution casting method and the effects of electron beam on structural, thermal and antibacterial responses of the prepared films were studied. The electron irradiation for different doses was carried out using 8 MeV Microtron facility at Mangalore University. The changes in microstructural parameters and thermal stability of the films were investigated using Wide Angle X-ray Scattering (WAXS) and thermogravimetric analysis (TGA) respectively. Both microstructuralline parameters (crystallite size and lattice strain (g in %)) and thermal stability of the irradiated films have increased with radiation dosage. Agar diffusion method demonstrated the antibacterial activity of SF film which was increased after irradiation on both Gram-positive and Gram-negative species.

  8. Total skin electron beam irradiation for cutaneous T-cell lymphoma (mycosis fungoides)

    Energy Technology Data Exchange (ETDEWEB)

    Vloten, W.A. Van; Vroome, H. De; Noordijk, E.M. (Rijksuniversiteit Leiden (Netherlands))

    1985-06-01

    Forty patients with the cutaneous T-cell lymphoma (mycosis fungoides) were treated with total skin electron beam irradiation. The total follow-up period was up to 116 months (median 57.5 months). The patients were irradiated with a total dose of 35 Gy over 10 weeks, using the six-field technique. Ten of these patients had lymph node involvement and were subsequently treated with chemotherapy. After the initial electron irradiation complete remission of the skin lesions was obtained in 87.5% of the patients. Relapse of skin lesions occurred in 52% of the patients after 2-72 months (median 4 months). Second line therapy consisted primarily of topical nitrogen mustard. The overall survival rate at 5 years was 70%. Despite the side-effects this treatment was tolerated well by all patients.

  9. Controlled growth of bismuth nanoparticles by electron beam irradiation in TEM

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seon Ho [College of Environment and Applied Chemistry, Kyung Hee University, Yongin 449-701 (Korea, Republic of); Choi, Young-Suk [Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973 (United States); Kang, Kyongha [Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)]. E-mail: kkang@bnl.gov; Yang, Sung Ik [College of Environment and Applied Chemistry, Kyung Hee University, Yongin 449-701 (Korea, Republic of)]. E-mail: siyang@khu.ac.kr

    2007-01-16

    In situ nanometer-sized bismuth particles were synthesized by irradiation of the electron beam in the TEM. The size of the crystalline Bi nanoparticles could be controlled by adjusting the irradiation time of the electron beam. Characterization of TEM reveals that the Bi nanoparticles exist in rhombic structure, same as to bulk Bi.

  10. Development of over-production strain of saccharification enzyme and biomass pretreatment by proton beam irradiation

    International Nuclear Information System (INIS)

    - The first year : Pre-treatment of biomass by proton beam irradiation and characterization of the pretreated biomass by IR and SEM - The second year : Strain development by proton beam irradiation for the production of cellulase and hemicellulase - The third year : Optimization of Saccharification process by cellulase and hemicellulase

  11. Thermal and mechanical properties of e-beam irradiated butt-fusion joint in high-density polyethylene pipes

    Science.gov (United States)

    Vijayan, Vipin; Pokharel, Pashupati; Kang, Min Kwan; Choi, Sunwoong

    2016-05-01

    The effects of electron beam irradiation on the thermal and mechanical properties of a butt-fusion joint in high density polyethylene (HDPE) pipes were investigated. Differential scanning calorimetry, X-ray diffraction, and Fourier transform infra-red spectroscopy of welded samples revealed the changes of crystallinity due to the cross linking effect of electron beam irradiation. The suppression of the degree of crystallinity with increasing the irradiation dose from 0 kGy to 500 kGy indicated that the e-beam radiation induced cross-links among the polymer chains at the weld zone. The cross-link junction at the joint of HDPE pipe prevented chain folding and reorganization leading to the formation of imperfect crystallites with smaller size and also less in content. Tensile test of the welded samples with different dose of e-beam irradiation showed the increased values of the yield stress and Young's modulus as a function of irradiation dose. On the other hand, the elongation at break diminished clearly with increasing the irradiation doses.

  12. Characterization of polymeric films subjected to lithium ion beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gary S. Groenewold; W. Roger Cannon; Paul A. Lessing; Recep Avci; Muhammedin Deliorman; Mark Wolfenden; Doug W. Akers; J. Keith Jewell

    2013-02-01

    Two different polymeric materials that are candidate materials for use as binders for mixed uranium–plutonium oxide nuclear fuel pellets were subjected to Li ion beam irradiation, in order to simulate intense alpha irradiation. The materials (a polyethylene glycol 8000 and a microcrystalline wax) were then analyzed using a combination of mass spectrometry (MS) approaches and X-ray photoelectron spectroscopy (XPS). Samples of the irradiated PEG materials were dissolved in H2O and then analyzed using electrospray ionization-MS, which showed the formation of a series of small oligomers in addition to intact large PEG oligomers. The small oligomers were likely formed by radiation-induced homolytic scissions of the C–O and C–C bonds, which furnish radical intermediates that react by radical recombination with Hradical dot and OHradical dot. Surface analysis using SIMS revealed a heterogeneous surface that contained not only PEG-derived polymers, but also hydrocarbon-based entities that are likely surface contaminants. XPS of the irradiated PEG samples indicated the emergence of different carbon species, with peak shifts suggesting the presence of sp2 carbon atoms. Analysis of the paraffinic film using XPS showed the emergence of oxygen on the surface of the sample, and also a broadening and shifting of the C1s peak, demonstrating a change in the chemistry on the surface. The paraffinic film did not dissolve in either H2O or a H2O–methanol solution, and hence the bulk of the material could not be analyzed using electrospray. However a series of oligomers was leached from the bulk material that produced ion series in the ESI-MS analyses that were identified octylphenyl ethoxylate oligomers. Upon Li ion bombardment, these shifted to a lower average molecular weight, but more importantly showed the emergence of three new ion series that are being formed as a result of radiation damage. Surface analysis of the paraffinic polymers using SIMS produced spectra that were

  13. Characterization of polymeric films subjected to lithium ion beam irradiation

    Science.gov (United States)

    Groenewold, Gary S.; Cannon, W. Roger; Lessing, Paul A.; Avci, Recep; Deliorman, Muhammedin; Wolfenden, Mark; Akers, Doug W.; Jewell, J. Keith; Zuck, Larry D.

    2013-02-01

    Two different polymeric materials that are candidate materials for use as binders for mixed uranium-plutonium oxide nuclear fuel pellets were subjected to Li ion beam irradiation, in order to simulate intense alpha irradiation. The materials (a polyethylene glycol 8000 and a microcrystalline wax) were then analyzed using a combination of mass spectrometry (MS) approaches and X-ray photoelectron spectroscopy (XPS). Samples of the irradiated PEG materials were dissolved in H2O and then analyzed using electrospray ionization-MS, which showed the formation of a series of small oligomers in addition to intact large PEG oligomers. The small oligomers were likely formed by radiation-induced homolytic scissions of the C-O and C-C bonds, which furnish radical intermediates that react by radical recombination with Hrad and OHrad . Surface analysis using SIMS revealed a heterogeneous surface that contained not only PEG-derived polymers, but also hydrocarbon-based entities that are likely surface contaminants. XPS of the irradiated PEG samples indicated the emergence of different carbon species, with peak shifts suggesting the presence of sp2 carbon atoms. Analysis of the paraffinic film using XPS showed the emergence of oxygen on the surface of the sample, and also a broadening and shifting of the C1s peak, demonstrating a change in the chemistry on the surface. The paraffinic film did not dissolve in either H2O or a H2O-methanol solution, and hence the bulk of the material could not be analyzed using electrospray. However a series of oligomers was leached from the bulk material that produced ion series in the ESI-MS analyses that were identified octylphenyl ethoxylate oligomers. Upon Li ion bombardment, these shifted to a lower average molecular weight, but more importantly showed the emergence of three new ion series that are being formed as a result of radiation damage. Surface analysis of the paraffinic polymers using SIMS produced spectra that were wholly dominated by

  14. Electron Beam Irradiation Dose Dependently Damages the Bacillus Spore Coat and Spore Membrane

    Directory of Open Access Journals (Sweden)

    S. E. Fiester

    2012-01-01

    Full Text Available Effective control of spore-forming bacilli begs suitable physical or chemical methods. While many spore inactivation techniques have been proven effective, electron beam (EB irradiation has been frequently chosen to eradicate Bacillus spores. Despite its widespread use, there are limited data evaluating the effects of EB irradiation on Bacillus spores. To study this, B. atrophaeus spores were purified, suspended in sterile, distilled water, and irradiated with EB (up to 20 kGy. Irradiated spores were found (1 to contain structural damage as observed by electron microscopy, (2 to have spilled cytoplasmic contents as measured by spectroscopy, (3 to have reduced membrane integrity as determined by fluorescence cytometry, and (4 to have fragmented genomic DNA as measured by gel electrophoresis, all in a dose-dependent manner. Additionally, cytometry data reveal decreased spore size, increased surface alterations, and increased uptake of propidium iodide, with increasing EB dose, suggesting spore coat alterations with membrane damage, prior to loss of spore viability. The present study suggests that EB irradiation of spores in water results in substantial structural damage of the spore coat and inner membrane, and that, along with DNA fragmentation, results in dose-dependent spore inactivation.

  15. Effect of hydrogenation on the luminescence evolution of GaN under low energy electron beam irradiation%氢化作用对低能电子束辐照下GaN发光演变的影响

    Institute of Scientific and Technical Information of China (English)

    王彦; 沈波; Dierre Benjamin; Sekiguchi Takashi; 许福军

    2009-01-01

    Luminescence evolution of GaN irradiated by low energy electron beam before and after hydrogenation has been investigated by means of cathodoluminescence (CL), in connection with the diffusion properties of hydrogen in GaN. It is found that under low energy electron beam irradiation, the band to band emission of GaN shows a decrease before hydrogenation, while it shows an initial increase and a subsequent decrease after hydrogenation, and the decrease after hydrogenation is relatively weak. Moreover, there is no luminescence recovery in 20 hours after the first irradiation after hydrogenation. The experimental results indicate a luminescence enhancement effect of hydrogen by passivating certain defects in GaN. However, such effect must be realized by overcoming high migration barrier in GaN. In the experiments, low energy electron beam supports enough energy to hydrogen to diffuse and passivate defects in CaN. These results show strongly the importance of diffusion of hydrogen in the passivation process in semiconductors.%结合氢在GaN中的扩散特性,运用阴极荧光(CL)谱,对氢化前后低能电子束辐照下GaN带边发光强度的演变进行了研究.实验发现,氢化前GaN在低能电子束辐照下带边发光强度呈现衰减的趋势,而氢化后带边发射强度先上升后衰减,而且氢化后的衰减比氢化前弱.1 h辐照过程中,氢化后GaN带边发光强度的变化比氢化前要小很多.另外,实验中发现经过氢化处理的GaN在辐照后20 h内没有观察到带边发射强度的恢复.研究表明氢原子在GaN中可以钝化缺陷来增强发光,但这种钝化缺陷的作用必须通过克服高的扩散势垒来实现,而低能电子束可以提供足够的能量使得氢原子克服扩散势垒来实现钝化作用.研究实验充分证明了氢的扩散是GaN中实现氢钝化作用的一个重要前提.

  16. Hydrogel coating of RVNRL film by electron beam irradiation

    International Nuclear Information System (INIS)

    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

  17. Luminescence imaging of water during proton-beam irradiation for range estimation

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi, E-mail: s-yama@met.nagoya-u.ac.jp; Okumura, Satoshi; Komori, Masataka [Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya 461-8673 (Japan); Toshito, Toshiyuki [Department of Proton Therapy Physics, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Nagoya 462-8508 (Japan)

    2015-11-15

    Purpose: Proton therapy has the ability to selectively deliver a dose to the target tumor, so the dose distribution should be accurately measured by a precise and efficient method. The authors found that luminescence was emitted from water during proton irradiation and conjectured that this phenomenon could be used for estimating the dose distribution. Methods: To achieve more accurate dose distribution, the authors set water phantoms on a table with a spot scanning proton therapy system and measured the luminescence images of these phantoms with a high-sensitivity, cooled charge coupled device camera during proton-beam irradiation. The authors imaged the phantoms of pure water, fluorescein solution, and an acrylic block. Results: The luminescence images of water phantoms taken during proton-beam irradiation showed clear Bragg peaks, and the measured proton ranges from the images were almost the same as those obtained with an ionization chamber. Furthermore, the image of the pure-water phantom showed almost the same distribution as the tap-water phantom, indicating that the luminescence image was not related to impurities in the water. The luminescence image of the fluorescein solution had ∼3 times higher intensity than water, with the same proton range as that of water. The luminescence image of the acrylic phantom had a 14.5% shorter proton range than that of water; the proton range in the acrylic phantom generally matched the calculated value. The luminescence images of the tap-water phantom during proton irradiation could be obtained in less than 2 s. Conclusions: Luminescence imaging during proton-beam irradiation is promising as an effective method for range estimation in proton therapy.

  18. Post-irradiation effects in polyethylenes irradiated under various atmospheres

    International Nuclear Information System (INIS)

    If a large amount of polymer free radicals remain trapped after irradiation of polymers, the post-irradiation effects may result in a significant alteration of physical properties during long-term shelf storage and use. In the case of polyethylenes (PEs) some failures are attributed to the post-irradiation oxidative degradation initiated by the reaction of residual free radicals (mainly trapped in crystal phase) with oxygen. Oxidation products such as carbonyl groups act as deep traps and introduce changes in carrier mobility and significant deterioration in the PEs electrical insulating properties. The post-irradiation behaviour of three different PEs, low density polyethylene (LDPE), linear low density polyethylene (LLDPE) and high density polyethylene (HDPE) was studied; previously, the post-irradiation behaviour of the PEs was investigated after the irradiation in air (Suljovrujic, 2010). In this paper, in order to investigate the influence of different irradiation media on the post-irradiation behaviour, the samples were irradiated in air and nitrogen gas, to an absorbed dose of 300 kGy. The annealing treatment of irradiated PEs, which can substantially reduce the concentration of free radicals, is used in this study, too. Dielectric relaxation behaviour is related to the difference in the initial structure of PEs (such as branching, crystallinity etc.), to the changes induced by irradiation in different media and to the post-irradiation changes induced by storage of the samples in air. Electron spin resonance (ESR), differential scanning calorimetry (DSC), infra-red (IR) spectroscopy and gel measurements were used to determine the changes in the free radical concentration, crystal fraction, oxidation and degree of network formation, respectively. - Highlights: • The post-irradiation behaviour of three different PEs, LDPE, LLDPE and HDPE, was studied. • In order to investigate influence of different irradiation media on post-irradiation behaviour, samples

  19. Irradiation-Assisted Stress-Corrosion Cracking of Nitinol During eBeam Sterilization

    Science.gov (United States)

    Smith, Stuart A.; Gause, Brock; Plumley, David; Drexel, Masao J.

    2012-12-01

    Medical device fractures during gamma and electron beam (eBeam) sterilization have been reported. Two common factors in these device fractures were a constraining force and the presence of fluorinated ethylene propylene (FEP). This study investigated the effects of eBeam sterilization on constrained light-oxide nitinol wires in FEP. The goal was to recreate these fractures and determine their root cause. Superelastic nitinol wires were placed inside FEP tubes and constrained with nominal outer fiber strains of 10, 15, and 20%. These samples were then subjected to a range of eBeam sterilization doses up to 400 kGy and compared with unconstrained wires also subjected to sterilization. Fractures were observed at doses of >100 kGy. Analysis of the fracture surfaces indicated that the samples failed due to irradiation-assisted stress-corrosion cracking (IASCC). This same effect was also observed to occur with PTFE at 400 kGy. These results suggest that nitinol is susceptible to IASCC when in the presence of a constraining stress, fluorinated polymers, and irradiation.

  20. Dose rate effect in food irradiation

    International Nuclear Information System (INIS)

    It has been suggested that the minor losses of nutrients associated with radiation processing may be further reduced by irradiating foods at the high dose rates generally associated with electron beams from accelerators, rather than at the low dose rates typical of gamma irradiation (e.g. 60Co). This review briefly examines available comparative data on gamma and electron irradiation of foods to evaluate these suggestions. (137 refs., 27 tabs., 11 figs.)

  1. Beam-beam effect seen through forced vibration

    International Nuclear Information System (INIS)

    In electron accelerator, tune is measured by giving beam transverse forced vibration caused by RF frequency. It is well known that beam-beam parameter can be measured if beam-beam interaction exists. Generally, small value is chosen as the amplitude of forced vibration, and many researches were done in this case. In this report, we discuss effect of resonance caused by beam-beam interaction in case of amplitude of forced vibration being big. (author)

  2. Production of a thermal stress resistant mutant Euglena gracilis strain using Fe-ion beam irradiation.

    Science.gov (United States)

    Yamada, Koji; Kazama, Yusuke; Mitra, Sharbanee; Marukawa, Yuka; Arashida, Ryo; Abe, Tomoko; Ishikawa, Takahiro; Suzuki, Kengo

    2016-08-01

    Euglena gracilis is a common phytoplankton species, which also has motile flagellate characteristics. Recent research and development has enabled the industrial use of E. gracilis and selective breeding of this species is expected to further expand its application. However, the production of E. gracilis nuclear mutants is difficult because of the robustness of its genome. To establish an efficient mutation induction procedure for E. gracilis, we employed Fe-ion beam irradiation in the RIKEN RI beam factory. A decrease in the survival rate was observed with the increase in irradiation dose, and the upper limit used for E. gracilis selective breeding was around 50 Gy. For a practical trial of Fe-ion irradiation, we conducted a screening to isolate high-temperature-tolerant mutants. The screening yielded mutants that proliferated faster than the wild-type strain at 32 °C. Our results demonstrate the effectiveness of heavy-ion irradiation on E. gracilis selective breeding. PMID:27075598

  3. Magnetic modification at sub-surface of FeRh bulk by energetic ion beam irradiation

    Science.gov (United States)

    Koide, T.; Uno, H.; Sakane, H.; Sakamaki, M.; Amemiya, K.; Iwase, A.; Matsui, T.

    2015-05-01

    Ferromagnetic layered structure has been made at sub-surface of the antiferromagnetic FeRh bulk samples by high energy He ion beam irradiation. In accordance with the Transport of Ions in Matter simulation, such ion beam can effectively deposit the elastic collision energy in several μm regions in the depth from the surface. Measurement with a superconducting quantum interference device reveals the irradiated samples to be ferromagnetic. Assuming that only the part the energy deposited can be modified to be ferromagnetic, the corresponding irradiation induced magnetization is consistent with the data that we previously reported. On the other hand, the X-ray magnetic circular dichroism (XMCD) spectra for the irradiated samples are totally unchanged as those for the unirradiated samples. Since XMCD signal in total emission yield method is considered to be surface sensitive with a typical probing depth of several nm, the surface magnetic state is maintained to be antiferromagnetic. By utilizing these phenomena, three-dimensional magnetic patterning of FeRh can be realized, which may potentially be used for future magnetic exchange device application such as nano-scale sensors and memories.

  4. Magnetic modification at sub-surface of FeRh bulk by energetic ion beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Koide, T.; Iwase, A. [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Uno, H.; Sakane, H. [S. H. I. Examination and Inspection, Ltd., Saijo, Ehime 799-1393 (Japan); Sakamaki, M.; Amemiya, K. [High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Matsui, T., E-mail: t-matsui@21c.osakafu-u.ac.jp [Research Organization for the 21st Century, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan)

    2015-05-07

    Ferromagnetic layered structure has been made at sub-surface of the antiferromagnetic FeRh bulk samples by high energy He ion beam irradiation. In accordance with the Transport of Ions in Matter simulation, such ion beam can effectively deposit the elastic collision energy in several μm regions in the depth from the surface. Measurement with a superconducting quantum interference device reveals the irradiated samples to be ferromagnetic. Assuming that only the part the energy deposited can be modified to be ferromagnetic, the corresponding irradiation induced magnetization is consistent with the data that we previously reported. On the other hand, the X-ray magnetic circular dichroism (XMCD) spectra for the irradiated samples are totally unchanged as those for the unirradiated samples. Since XMCD signal in total emission yield method is considered to be surface sensitive with a typical probing depth of several nm, the surface magnetic state is maintained to be antiferromagnetic. By utilizing these phenomena, three-dimensional magnetic patterning of FeRh can be realized, which may potentially be used for future magnetic exchange device application such as nano-scale sensors and memories.

  5. Irradiation effects upon activities of fission product iodine

    International Nuclear Information System (INIS)

    This report describes the experimental study of the irradiation effects upon activities of fission product iodine made in the period from June, 1981 to March, 1982. Chemical transport of iron was studied under irradiation of cesium iodide by electron beam. Deposited ion was identified on the high temperature surface, which can be taken to certify the appropriateness of the model of the iodine-including chemical transport of stainless-steel cladding components to fuel in the LMFBR fuel pins. (author)

  6. Characterization of polymeric films subjected to lithium ion beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Groenewold, Gary S., E-mail: gary.groenewold@inl.gov [Idaho National Laboratory, 2351 North Boulevard, Idaho Falls, ID 83415-2208 (United States); Cannon, W. Roger; Lessing, Paul A. [Idaho National Laboratory, 2351 North Boulevard, Idaho Falls, ID 83415-2208 (United States); Avci, Recep; Deliorman, Muhammedin; Wolfenden, Mark [Image and Chemical Analysis Laboratory, Montana State University, Bozeman, MT 59717 (United States); Akers, Doug W.; Jewell, J. Keith; Zuck, Larry D. [Idaho National Laboratory, 2351 North Boulevard, Idaho Falls, ID 83415-2208 (United States)

    2013-02-01

    Highlights: ► Polyethylene glycol (PEG) and paraffinic polymers were subjected to Li ion irradiation. ► Small oligomers detected in irradiated PEG by electrospray ionization (ESI) mass spectrometry. ► Radiolytic scission observed in X-ray photoelectron and electrospray ionization mass spectra. ► Radiation modified paraffinics characterized by changes in non-ionic surfactant additives. ► Results suggest that extent of radiolysis, and radiolytic pathways can be inferred. -- Abstract: Two different polymeric materials that are candidate materials for use as binders for mixed uranium–plutonium oxide nuclear fuel pellets were subjected to Li ion beam irradiation, in order to simulate intense alpha irradiation. The materials (a polyethylene glycol 8000 and a microcrystalline wax) were then analyzed using a combination of mass spectrometry (MS) approaches and X-ray photoelectron spectroscopy (XPS). Samples of the irradiated PEG materials were dissolved in H{sub 2}O and then analyzed using electrospray ionization-MS, which showed the formation of a series of small oligomers in addition to intact large PEG oligomers. The small oligomers were likely formed by radiation-induced homolytic scissions of the C–O and C–C bonds, which furnish radical intermediates that react by radical recombination with H{sup ·} and OH{sup ·}. Surface analysis using SIMS revealed a heterogeneous surface that contained not only PEG-derived polymers, but also hydrocarbon-based entities that are likely surface contaminants. XPS of the irradiated PEG samples indicated the emergence of different carbon species, with peak shifts suggesting the presence of sp{sup 2} carbon atoms. Analysis of the paraffinic film using XPS showed the emergence of oxygen on the surface of the sample, and also a broadening and shifting of the C1s peak, demonstrating a change in the chemistry on the surface. The paraffinic film did not dissolve in either H{sub 2}O or a H{sub 2}O–methanol solution, and

  7. Fabrication of Rubrene Thin Film Transistor on Polystyrene Irradiated by Electron Beam

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Joon; Park, Jiwon; Cho, Sung Oh [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Lee, Hyeok Moo [LG Chem Research Park Battery Tech Center, Daejeon (Korea, Republic of); Lee, Junghwi; Cho, Sung Oh [Hanbat National Univ., Daejeon (Korea, Republic of)

    2014-05-15

    We present an unprecedented method to fabricate high-crystalline rubrene TFTs by combining of the abrupt heating technique and the polystyrene buffer layer irradiated by electron beam. For this PS buffer layer, we irradiated electron beam of optimized fluences. By electron beam irradiation, the hydrocarbon chains of PS were cross-linked without any initiators or agents, and chain segmental motions of PS were appeared at the irradiated area. Subsequently, abrupt heating of samples changed the crystalline phase of rubrene from as-deposited amorphous to orthorhombic phase only at irradiated samples without giving any damage to semiconductor. In summary, we have presented an unconventional approach to fabricate crystalline rubrene active layers and high quality rubrene thin film transistors. By using electron beam irradiation of PS and subsequent crystallization induced by abrupt heating, orthorhombic phase rubrene with high crystalline quality was fabricated successfully. We believe that this unprecedented technique using crosslinking of dielectric layer can be applied to not only PS but also many polymeric materials which can be cross-linked by electron beam. Furthermore, we could expect that by patterning of electron beam, in other words selective irradiation of electron beam, patterned rubrene with high resolution can be realized by adopting direct electron beam lithography techniques.

  8. Fast crystallization of amorphous Gd2Zr2O7 induced by thermally activated electron-beam irradiation

    International Nuclear Information System (INIS)

    We investigate the ionization and displacement effects of an electron-beam (e-beam) on amorphous Gd2Zr2O7 synthesized by the co-precipitation and calcination methods. The as-received amorphous specimens were irradiated under electron beams at different energies (80 keV, 120 keV, and 2 MeV) and then characterized by X-ray diffraction and transmission electron microscopy. A metastable fluorite phase was observed in nanocrystalline Gd2Zr2O7 and is proposed to arise from the relatively lower surface and interface energy compared with the pyrochlore phase. Fast crystallization could be induced by 120 keV e-beam irradiation (beam current = 0.47 mA/cm2). The crystallization occurred on the nanoscale upon ionization irradiation at 400 °C after a dose of less than 1017 electrons/cm2. Under e-beam irradiation, the activation energy for the grain growth process was approximately 10 kJ/mol, but the activation energy was 135 kJ/mol by calcination in a furnace. The thermally activated ionization process was considered the fast crystallization mechanism

  9. Changes in functional properties of sugar beet and citrus pectins by irradiation with electron beam

    International Nuclear Information System (INIS)

    Changes in functional properties of pectin extracted from sugar beet or citrus peel by electron beam in solid state or aqueous solution were investigated. Citrus pectin (CP) was degraded at both solid state and aqueous solution by irradiation with electron beam. Sugar beet pectin (SBP) was degraded at solid state but in aqueous solution at high concentrate was polymerized by irradiation with electron beam. SBP polymerized by electron beam formed hydrogel. This hydrophilic polymer was useful as water absorbent. Moreover, it was confirmed that the emulsification stability and acidified milk beverage stabilization of SBP was enhanced by electron beam. (author)

  10. A Monte Carlo evaluation of beam characteristics for total body irradiation at extended treatment distances.

    Science.gov (United States)

    Chakarova, Roumiana; Krantz, Marcus

    2014-05-08

    The aim is to study beam characteristics at large distances when focusing on the electron component. In particular, to investigate the utility of spoilers with various thicknesses as an electron source, as well as the effect of different spoiler-to-surface distances (STSD) on the beam characteristics and, consequently, on the dose in the superficial region. A MC model of a 15 MV Varian accelerator, validated earlier by experimental data at isocenter and extended distances used in large-field total body irradiation, is applied to evaluate beam characteristics at distances larger than 400 cm. Calculations are carried out using BEAMnrc/DOSXYZnrc code packages and phase space data are analyzed by the beam data processor BEAMdp. The electron component of the beam is analyzed at isocenter and extended distances, with and without spoilers as beam modifiers, assuming vacuum or air surrounding the accelerator head. Spoiler thickness of 1.6 cm is found to be optimal compared to thicknesses of 0.8 cm and 2.4 cm. The STSD variations should be taken into account when treating patients, in particular when the treatment protocols are based on a fixed distance to the patient central sagittal plane, and also, in order to maintain high dose in the superficial region.

  11. Electron beam irradiation of sun-dried apricots for quality maintenance

    International Nuclear Information System (INIS)

    The chemical, sensory, and microbial quality parameters of electron beam (EB)-irradiated and non-irradiated sun-dried apricots were periodically evaluated to optimize the EB irradiation of sun-dried apricots for quality maintenance. The sun-dried apricots were treated with 1.0, 2.0, 3.0, 4.0, and 5.0 kGy of EB and subsequently stored at ambient temperature. EB treatment at 1.0–3.0 kGy proved to be beneficial for retaining high levels of β-carotene, ascorbic acid, titratable acidity, total sugars, and color without any significant effect on sensory properties. Doses of 1.0–3.0 kGy retained the β-carotene content of sun-dried apricots to 8.21%, 9.27%, and 10.43% compared with 6.09% in control samples after 10 months of storage. After 10 months of storage, the maximum losses of ascorbic acid were 37.8% in control samples and 35.5% in 3.0 kGy-irradiated samples. Titratable acidity and total sugars were significantly enhanced immediately after 1.0–3.0 kGy irradiation treatment, and both parameters showed no significant change after 10 months of storage. Samples subjected to EB treatment at 3.0 kGy maintained a high overall acceptability of sun-dried apricots. Decreased number of viable microorganisms to below detection limits were observed after 3.0 kGy irradiation, and compared with the control, the logarithmic reductions after 10 months of storage were 0.98 for yeast and mold count, as well as 1.71 for bacterial count. - Highlights: • Electron beam irradiation was used for sun-dried apricots quality maintenance. • The chemical, sensory, and microbial quality parameters of apricots were evaluated. • 1.0–3.0 kGy proved to be beneficial for retaining high levels of apricots quality. • 3.0 kGy of irradiation maintained a high overall acceptability of sun-dried apricots. • 3.0 kGy of irradiation reduced the viable microorganisms to below detection limits

  12. Structure modification and medical application of the natural products by proton beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D. W.; Park, J. K.; Kang, J. E.; Shin, S. C.; Ahn, J. H.; Lee, E. S. [Dongguk University, Gyeongju (Korea, Republic of)

    2008-04-15

    This study was performed for the investigation of changes of constituent contents of Korean ginseng (Panax genseng C.A. Meyer) after proton beam irradiation (Beam energy from MC-50 cyclotron : 36.5MeV) with beam range of 500 - 10000Gy

  13. Structure modification and medical application of the natural products by proton beam irradiation

    International Nuclear Information System (INIS)

    This study was performed for the investigation of changes of constituent contents of Korean ginseng (Panax genseng C.A. Meyer) after proton beam irradiation (Beam energy from MC-50 cyclotron : 36.5MeV) with beam range of 500 - 10000Gy

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

    International Nuclear Information System (INIS)

    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;M4, rabbit muscle LDH;H4, chicken heart LDH;M3H1). 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, M4 enzyme was increased its enzymatic activity by the irradiations of low-level doses. 3) For the H4 enzymes, an increasing phenomenon of -SH group was found in the low-level doses of electron beam irradiation. (author)

  15. Diffraction of a Laser Beam.

    Science.gov (United States)

    Jodoin, Ronald E.

    1979-01-01

    Investigates the effect of the nonuniform irradiance across a laser beam on diffraction of the beam, specifically the Fraunhofer diffraction of a laser beam with a Gaussian irradiance profile as it passes through a circular aperture. (GA)

  16. Beam-beam effects in the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V.; Alexahin, Y.; Lebedev, V.; Lebrun, P.; Moore, R.S.; Sen, T.; Tollestrup, A.; Valishev, A.; Zhang, X.L.; /Fermilab

    2005-01-01

    The Tevatron in Collider Run II (2001-present) is operating with 6 times more bunches, many times higher beam intensities and luminosities than in Run I (1992-1995). Electromagnetic long-range and head-on interactions of high intensity proton and antiproton beams have been significant sources of beam loss and lifetime limitations. We present observations of the beam-beam phenomena in the Tevatron and results of relevant beam studies. We analyze the data and various methods employed in operations, predict the performance for planned luminosity upgrades, and discuss ways to improve it.

  17. Linear Energy Transfer-Dependent Change in Rice Gene Expression Profile after Heavy-Ion Beam Irradiation

    Science.gov (United States)

    Ishii, Kotaro; Kazama, Yusuke; Morita, Ryouhei; Hirano, Tomonari; Ikeda, Tokihiro; Usuda, Sachiko; Hayashi, Yoriko; Ohbu, Sumie; Motoyama, Ritsuko; Nagamura, Yoshiaki; Abe, Tomoko

    2016-01-01

    A heavy-ion beam has been recognized as an effective mutagen for plant breeding and applied to the many kinds of crops including rice. In contrast with X-ray or γ-ray, the heavy-ion beam is characterized by a high linear energy transfer (LET). LET is an important factor affecting several aspects of the irradiation effect, e.g. cell survival and mutation frequency, making the heavy-ion beam an effective mutagen. To study the mechanisms behind LET-dependent effects, expression profiling was performed after heavy-ion beam irradiation of imbibed rice seeds. Array-based experiments at three time points (0.5, 1, 2 h after the irradiation) revealed that the number of up- or down-regulated genes was highest 2 h after irradiation. Array-based experiments with four different LETs at 2 h after irradiation identified LET-independent regulated genes that were up/down-regulated regardless of the value of LET; LET–dependent regulated genes, whose expression level increased with the rise of LET value, were also identified. Gene ontology (GO) analysis of LET-independent up-regulated genes showed that some GO terms were commonly enriched, both 2 hours and 3 weeks after irradiation. GO terms enriched in LET-dependent regulated genes implied that some factor regulates genes that have kinase activity or DNA-binding activity in cooperation with the ATM gene. Of the LET-dependent up-regulated genes, OsPARP3 and OsPCNA were identified, which are involved in DNA repair pathways. This indicates that the Ku-independent alternative non-homologous end-joining pathway may contribute to repairing complex DNA legions induced by high-LET irradiation. These findings may clarify various LET-dependent responses in rice. PMID:27462908

  18. Effects of irradiation on the components of implantable pacemakers

    International Nuclear Information System (INIS)

    The purpose of this study was to examine the effects of irradiation on implantable pacemaker components. The pacemaker was divided into three components: lead wire and electrode, battery, and electrical circuit, and each component was irradiated by X-ray and electron beams, respectively. The pacemaker parameters were measured by both telemetry data of the programmer and directly measured data from the output terminal. The following results were obtained. For the lead wire and electrode, there was no effect on the pacemaker function due to irradiation by X-ray and electron beams. In the case of battery irradiation, there was no change in battery voltage or current up to 236 Gy X-ray dose. In the electrical circuit, the pacemaker reverted to the regular beating rate (fixed-rate mode) immediately after the start of X-ray irradiation, and it continued in this mode during irradiation. In patients with their own heartbeat rhythm, changing to the fixed-rate mode may cause dangerous conditions such as ventricular fibrillation. When the accumulated irradiation dose is increased, another failure can be seen in the output voltage of the pacemaker. The pacing output voltage dropped rapidly by about 40% at 30-88 Gy. Decreasing the output voltage results in pacing disorders, and heart failure may occur. In the telemetry data of the programmer, no change in output voltage could be detected, highlighting the difference between telemetry data and actual pacing data. (author)

  19. 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.

  20. Defocusing beam line design for an irradiation facility at the TAEA SANAEM Proton Accelerator Facility

    Science.gov (United States)

    Gencer, A.; Demirköz, B.; Efthymiopoulos, I.; Yiğitoğlu, M.

    2016-07-01

    Electronic components must be tested to ensure reliable performance in high radiation environments such as Hi-Limu LHC and space. We propose a defocusing beam line to perform proton irradiation tests in Turkey. The Turkish Atomic Energy Authority SANAEM Proton Accelerator Facility was inaugurated in May 2012 for radioisotope production. The facility has also an R&D room for research purposes. The accelerator produces protons with 30 MeV kinetic energy and the beam current is variable between 10 μA and 1.2 mA. The beam kinetic energy is suitable for irradiation tests, however the beam current is high and therefore the flux must be lowered. We plan to build a defocusing beam line (DBL) in order to enlarge the beam size, reduce the flux to match the required specifications for the irradiation tests. Current design includes the beam transport and the final focusing magnets to blow up the beam. Scattering foils and a collimator is placed for the reduction of the beam flux. The DBL is designed to provide fluxes between 107 p /cm2 / s and 109 p /cm2 / s for performing irradiation tests in an area of 15.4 cm × 21.5 cm. The facility will be the first irradiation facility of its kind in Turkey.

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

    International Nuclear Information System (INIS)

    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)

  2. Surface characterization of electron-beam irradiated polymer brushes

    International Nuclear Information System (INIS)

    Polymer brushes out of PS, P2VP, PNIPAMM and PAA were used to modify and control the surface potential of Si-wafers. The polymers brushes formed layers of thickness of less than 20 nm and significantly changed the surface potential of the substrate, which was investigated with contact angle measurements. Their chemical composition was studied by XPS. Electron irradiation was employed to modify the brushes by different radiation doses. With XPS and Zetapotential measurements we were able to specify the surface composition after electron beam treatment. Changes in surface composition and the structure of the grafted polymer brushes allowed to qualify cross-linkages and degradation processes. By varying the dose we could adjust on the one hand the decomposition of the polymer and on the other hand the amount of hydrophilic groups. We know that the adsorption of proteins on polymers highly depends on the surface potential. This work could be used to control the surface potential of the polymer brush as well as the adsorption of proteins, only by varying the radiation dose. The chosen substrate silicon is also attractive for lab-on-chip applications of those modified brushes. (orig.)

  3. The conductivity of dielectrics during irradiation by scanning high power electron beam

    International Nuclear Information System (INIS)

    The conductivity of dielectrics under electron beam irradiation is fundamental question of physics for interaction of electron beams with condensed mater. The CW electron accelerator Rhodotron with scanning electron beams was used in the experiments. The electron beam has next main parameters: kinetic energy is 5 MeV, maximum power is 80 kW, and the scanning repetition is 100 Hz. The results of measurements are discussed

  4. Electron beam irradiation conditions and foam seat properties in polypropylene-polyethylene blends

    Science.gov (United States)

    Tokuda, S.; Kemmotsu, T.

    1995-02-01

    High expansion polypropylene foam (20-100kg/m 3) is industrially produced by blending polypropylene with thermal decomposition foaming agent, which is then irradiated with electron beam to induce crosslinking, and is finally heated, causing the foaming agent to decompose and generate foams. Here, crosslinking stage also serves to increase the melt viscosity of the mixture so that an appropriate value is obtained for foaming. In order to obtain desirable final product, the important factors in the above process are the material properties of the polypropylene and the appropriate control of crosslinking, which is governed by the selection of crosslinking-promoter and the irradiation conditions. We have used polypropylene random copolymer (R-PP) with low ethylene content and performed studies on the relation between the amount of electron beam irradiation and the degree of crosslinking and also on the effect of the multifunctional monomers as crosslinking-promoter. We have also produced foams using blends of this R-PP and linear low density polyethylene (L-LDPE) and evaluated their mechanical properties and their heat resistance.

  5. Nano-structural Modification of Amorphous Carbon Thin Films by Low-energy Electron Beam Irradiation

    Institute of Scientific and Technical Information of China (English)

    EijiIwamura; MasanoriYamaguchi

    2004-01-01

    A new approach using a low-energy electron beam radiation system was investigated to synthesize carbon hybrid structures in amorphous carbon thin films. Two types of amorphous carbon films, which were 15at% iron containing film and with column/inter-column structures, were deposited onto Si substrates by a sputtering technique and subsequently exposed to an electron shower of which the energy and dose rate were much smaller compared to an intense electron beam used in a transmission electron microscopy. As a result of the low-energy and low-dose electron irradiation process, graphitic structures formed in amorphous matrix at a relatively low temperature up to 450 K. Hybrid carbon thin films containing onion-like structures in an amorphous carbon matrix were synthesized by dynamic structural modification of iron containing amorphous carbon thin films. It was found that the graphitization progressed more in the electron irradiation than in annealing at 773K, and it was attributed to thermal and catalytic effects which are strongly related to grain growth of metal clusters. On the other hand, a reversal of TEM image contrast was observed in a-C films with column/inter-column structures. It is presumed that preferable graphitization occurred in the inter-column regions induced by electron irradiation.

  6. Nano-structural Modification of Amorphous Carbon Thin Films by Low-energy Electron Beam Irradiation

    Institute of Scientific and Technical Information of China (English)

    Eiji Iwamura; Masanori Yamaguchi

    2004-01-01

    A new approach using a low-energy electron beam radiation system was investigated to synthesize carbon hybrid structures in amorphous carbon thin films. Two types of amorphous carbon films, which were 15at% iron containing film and with column/inter-column structures, were deposited onto Si substrates by a sputtering technique and subsequently exposed to an electron shower of which the energy and dose rate were much smaller compared to an intense electron beam used in a transmission electron microscopy. As a result of the low-energy and low-dose electron irradiation process,graphitic structures formed in amorphous matrix at a relatively low temperature up to 450 K. Hybrid carbon thin films containing onion-like structures in an amorphous carbon matrix were synthesized by dynamic structural modification of iron containing amorphous carbon thin films. It was found that the graphitization progressed more in the electron irradiation than in annealing at 773K, and it was attributed to thermal and catalytic effects which are strongly related to grain growth of metal clusters. On the other hand, a reversal of TEM image contrast was observed in a-C films with column/inter-column structures. It is presumed that preferable graphitization occurred in the inter-column regions induced by electron irradiation.

  7. Numerical Simulations on Buckling Failure of Preloaded Cylindrical Shell Irradiated by High Power Laser Beam

    Institute of Scientific and Technical Information of China (English)

    王吉; 王肖钧; 王峰; 赵凯

    2004-01-01

    With finite-element software ANSYS 7.0 and simple thermal-mechanical coupling constitutive relations,the buckling failure of preloaded cylindrical shell irradiated by high power laser beam was studied by numerical simulations. The buckling mode and buckling critical loading were analysed for different preloading conditions. The influence of laser intensity, beam irradiation time, preloading conditions and geometric parameters of cylindrical shell on the buckling mode were discussed. The numerical results show that: ① the buckling deformation of the cylindrical shell was concentrated in the area of laser spot and the radial buckling was the main buckling mode, ② a linear relationship between the buckling eigenvalue and the maximum temperature at the center of laser spot was approached, ③ the buckling failure of cylindrical shell was attributed to the coupling effect of the material softening and the radial deformation in the laser spot, and hence to raise the stiffness of the material would enhance the ability for anti-irradiation of structure substantially.

  8. Treatment of keloid in upper limb by combined surgical excision and immediate postoperative electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, Kenichi; Yoshida, Jun; Heshiki, Takaya; Ishikura, Naotaka; Kawakami, Shigehiko [Kanazawa Medical Univ., Uchinada, Ishikawa (Japan)

    2002-02-01

    A scar in the upper extremities sometimes leads to onset of keloid, whose treatment is difficult and many treatment methods have been tried. Recently our hospital has performed electron beam radiation for treatment of keloid. In this report, we describe our examination on patients with keloid in the upper extremities who visited our hospital and underwent electron beam irradiation in these past 7 years. The patients were 9 males and 15 females, age between 9 and 84 (average age 26.6 years). Treatments included the following: Total ablation of keloid plus electron beam radiation, electron beam radiation alone, localized administration of triamcinolone. Treatment evaluation and presence or absence of pigmentation was examined. Electron beam radiation was performed with a total of 25 Gy for consecutive 5 days by 5 Gy electron beam since 1 week after keloid ablation with sufficient informed consent. Onset site of 24 patients with keloid in the upper extremities was the shoulder in 12 patients, the upper arm in 11, and the elbow in one patient. Development cause was BCG inoculation in 8 patients, wound associated with surgery in 6, unknown cause in 6, and others in 4 patients. The number of patients who were followed-up after treatment was 16 for each examination respectively, and mean followed-up period was 2 years and 10 months. Postoperative evaluation for ablation plus electron beam was good in 1 patient and fair in 6, that for electron beam radiation alone was good in 1, fair in 2, and unknown in 2, and that for triamcinolone was fair in 2, poor in 4, and unknown in 1 patient. Postoperative pigmentation was observed in all the patients immediately after radiation, and at the time of final follow-up, in 6 (33%) out of 9 patients confirmed. Ablation plus electron beam irradiation for keloid in the upper extremities was effective. However, this treatment cannot avoid a possibility of cancerogenesis. Thus, sufficient explanation and consent may be essential after full

  9. Effect of High Energy Electron Beam Irradiation on Epidermis Color of Certain Imported Fruits%高能电子束辐照处理对几种进口水果表皮色泽的影响

    Institute of Scientific and Technical Information of China (English)

    徐赟; 戚文元; 岳玲; 颜伟强; 包英姿; 孔秋莲

    2013-01-01

    以泰国青芒果(honeys)、澳大利亚红芒果(R2E2)和台湾二林种杨桃为试材,研究电子束辐照处理对果实表皮色泽的影响,为电子束辐照检疫进口水果提供参考依据.结果表明,三种水果经0.43、0.85、1.26、1.68 kGy剂量的电子束辐照后立即观测,未发现肉眼可见的色泽变化,但总色差计算分析表明,辐照处理可导致果实产生色差,其中以0.43 kGy处理的色差最小,1.68 kGy处理的最大.货架条件(15~25℃)存放7d后,不同辐照剂量处理的果皮色泽表现出明显的差异,果皮出现褐变,且剂量越大,褐变指数越高,其中泰国青芒果的后熟黄化受到抑制.因此,建议台湾二林种杨桃的适宜辐照剂量应在0.43 kGy以下,泰国青芒果和澳大利亚红芒果的适宜辐照剂量应在0.85 kGy以下.统计分析色泽参数(L*、a*、b*)与辐照剂量的相关性发现,三种水果果皮的红/绿轴参数a*与辐照剂量存在显著相关,在评价辐照果实色泽中具有重要意义.%In order to provide basis for irradiation use on quarantine of fresh fruits, effects of E -beam irradiation on skin color of mango (honeys, R2E2) and carambola were studied. Results showed that, macroscopical changes of fruits skin color were not occurred for those fruits which were just irradiated with doses of 0.43, 0.85, 1.26, 1.68 kGy. But the total color difference (△E) of fruits were detected, and 1.68 kGy treated fruits was higher than that of lower dose treated ones. After storage at shelf situation (15~25 ℃) for 7 days, the differences of skin color of which were treated at different dosage were macroscopical. Skins browning were observed which increased with the higher doses, and the ripening of honeys was inhibited. These results indicated that, the appropriate irradiation dose for carambola would be under 0.43 kGy while those for mango (honeys, R2E2) would be under 0.85 kGy. In addition, the correlation analysis between values of L

  10. Assessment of toxicity and genotoxicity of the reactive azo dyes Remazol Black B and Remazol Orange 3R and effectiveness of electron beam irradiation in the reduction of color and toxic effects

    International Nuclear Information System (INIS)

    organism Ceriodaphnia dubia and the NOEC and OEC values of RPB dye (sulphatoethylsulphone) were 12.5 and 25 mg L-1, respectively. After hydrolysis of the dye (vinylsulphone and hydroxyethyl sulphone) was shown to increase the values obtained from the NOEC and OEC. There was no chronic effect for the R3AR dye and its chemical forms to C. dubia. The comet assay adapted to haemocytes of Biomphalaria glabrata was used to assess the genotoxicity of the dyes. The RPB dye was genotoxic at highest concentrations (1 and 2 g L-1), with quantitative values of DNA damage equal to 117 and 112 and the R3AR dye was not genotoxic. The use of radiation with electron beams have proven effective in removing the color dyes. With a dose of 10 kGy a reduction of 97.64% and 96.8% for R3AR and RPB, respectively, was achieved. Possibly, the color removal was mainly due to the interaction of reactive species such as hydroxyl radicals generated in the radiolysis of water after the radiation beam of electrons. After radiation of the RPB dye a dose of 10 kGy reduced 59.52 % of the acute toxicity measured with Vibrio fischeri. For the other doses there was no significant reduction, as well as with Daphnia similis, where the values of EC5048h obtained were smaller than the non-irradiated dye. The R3AR dye showed better decreased toxicity after radiation when compared with the RPB, with reductions of 82.95% (V. fischeri) and 71.26% (D. similis) with 10 kGy. (author)

  11. Treatment result of so-called keloid with electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Masatsugu; Narabayashi, Isamu; Tatsumi, Toshiaki; Sueyoshi, Kozo; Uesugi, Yasuo; Nakata, Yasunobu; Tajima, Sadao [Osaka Medical Coll., Takatsuki (Japan)

    1999-03-01

    Between September 1993 and February 1997, 28 sites of so-called keloid (14 true keloids and 14 hypertrophic scars) were treated with electron beam irradiation. Twenty-five of these sites were treated with surgical excision followed by radiotherapy, and the other 3 sites received radiotherapy only. Irradiation by 9 MeV electron beam was performed for all patients, with a total dose of 20 Gy (10 fractions for 2 weeks). The results were evaluated at 8-49 months (Ave. 28.4 months) after treatment. Three sites treated with radiation more than 60 days after excision were excluded from evaluation of treatment response. Twenty-two of 25 sites showed complete response (CR) or partial response (PR). The control rate of total sites was 88.0%. The control rate was 92.9% in true keloids and 81.8% in hypertrophic scars. All keloid sites in the face, neck, shoulder, back and arm exhibited CR. One site of keloid in the head showed no response (NR). In 10 sites in the thoracic lesion, 8 were PR (80.0%) and 2 were NR (20.0%). In 8 sites in the abdominal lesion, 6 were CR (75.0%), 2 were PR (25.0%). All 3 non-operative sites exhibited PR. The control rate of sites treated with radiation within 14 days after keloid excision was 80.0% and that in sites treated more than 15 days after excision was 100.0%. Seven sites (7/28=25.0%) developed acute reaction, which were demonstrated erythema in the irradiated field, but this reaction was transient. Five sites (5/28=17.9%) showed hyperpigmentation indicating late reaction. The development of malignant tumor in or around the irradiated field was not shown. Postoperative electron beam irradiation was effective for so-called keloid. These data suggest that 10-fraction irradiation controls low grade of hyperpigmentation development, even though patients received a comparatively high total dose of radiotherapy. (author)

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

    International Nuclear Information System (INIS)

    It is described a methodology for waste water treatment which is simulated doing a benzene-toluene-phenol mixture in aqueous solution. Three different concentrations of them ones were used which were irradiated with electron beams coming from a Pelletron Accelerator carrying out the degradation effect of these compounds in CO2 and H2O. By mean of gas chromatography the analytical determinations were realized finding that in lower concentration of benzene and toluene performances of degradation higher than 95 % were obtained, but higher concentrations (100 ppm) the performance diminishes at 89 %, while for phenol in higher concentrations its degradation is over 60 % and in lower concentrations the degradation is under 80 %. The results are obtained with a constant irradiation time of 12 seconds and neutral pH. (Author

  13. Sensorial analysis of irradiated coffee (Coffea arabica L.) by electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Flavio T.; Fanaro, Gustavo B.; Koike, Amanda C.R.; Villavicencio, Anna Lucia C.H., E-mail: flaviot@ymail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Silva, Maria E.M. Pinto e [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Fac. de Saude Publica. Dept. de Nutricao

    2013-07-01

    Coffee is an important commodity and it is one of the most widely consumed beverages in the world. The acceptance of coffee by consumers depends mainly on the sensory characteristics of the beverage, that is its flavor, body, color, acidity and aroma. Food irradiation is processing technology environmental friendly and safety which aimed at the improvement of food quality. Depending on the absorbed radiation dose various effects can be achieved resulting in increase the shelf life, disinfestation, microorganism load reduction, without causing sensory changes to the food. Sensory analysis is the examination of a food through the evaluation of the attributes sensorial of product. The objective this paper was to evaluate the sensory properties, acceptance and purchase intent by the consumer of coffee (Coffea arabica L.) after the irradiation process with doses 6.0, 12.0 and 18.0kGy by electron beam. (author)

  14. Sensorial analysis of irradiated coffee (Coffea arabica L.) by electron beam

    International Nuclear Information System (INIS)

    Coffee is an important commodity and it is one of the most widely consumed beverages in the world. The acceptance of coffee by consumers depends mainly on the sensory characteristics of the beverage, that is its flavor, body, color, acidity and aroma. Food irradiation is processing technology environmental friendly and safety which aimed at the improvement of food quality. Depending on the absorbed radiation dose various effects can be achieved resulting in increase the shelf life, disinfestation, microorganism load reduction, without causing sensory changes to the food. Sensory analysis is the examination of a food through the evaluation of the attributes sensorial of product. The objective this paper was to evaluate the sensory properties, acceptance and purchase intent by the consumer of coffee (Coffea arabica L.) after the irradiation process with doses 6.0, 12.0 and 18.0kGy by electron beam. (author)

  15. 2 MeV, 60 kW dual-beam type electron accelerator irradiation facility

    International Nuclear Information System (INIS)

    The specification of new irradiation facility which has been constructed from 1978 through 1981 as the replacement of 1st Accelerator of JAERI, TRCRE are described. The accelerator is the Cockcroft-Walton type and both vertical and horizontal accelerating tubes are arranged on a single high voltage generator. Transferring of the high voltage to the horizontal accelerating tube is performed with the high voltage changing system in the pressure vessel. The output ratings of the accelerator are 2 MV of acceleration voltage and 30 mA of beam current. By providing the dual beam system, two irradiation rooms, one for vertical and the other for horizontal beam, are independently operationable. Persons can enter the horizontal irradiation room for experimental setting even when the vertical irradiation room is in operation. The specification of the buildings, the exhaust air treatment system, the irradiation conveyor and the safety observation system are also described. (author)

  16. Dry sliding tribological behavior of AZ31 magnesium alloy irradiated by high-intensity pulsed ion beam

    International Nuclear Information System (INIS)

    The dry sliding tribological behavior of AZ31 magnesium alloy irradiated by high-intensity pulsed ion beam (HIPIB) at energy density of 3.4 J/cm2 with 10 shots is investigated by dry sliding wear tests in order to explore the effect of HIPIB irradiation on tribological property of magnesium alloy. Surface morphologies, composition and structure of the irradiated AZ31 magnesium alloys are examined by electron probe microanalysis (EPMA) and X-ray diffraction (XRD). The results indicated that HIPIB irradiation led to the increase in surface microhardness and the reduction in friction coefficient and wear rate. Wear rate for both the original and the irradiated samples increased with increasing sliding load from 0.1 to 0.5 N. The transition from severe metallic wear to mild oxidative wear induced by HIPIB irradiation was observed by a combined analysis in surface morphology and chemical composition of wear tracks, mechanically mixed materials and wear debris, which is mainly attributed to the significant increase in microhardness resulting from grain refinement on the irradiated surface. In addition, defects induced by HIPIB irradiation promoted the diffusion of oxygen during sliding wear and therefore led to the formation of compact mixed materials and protective films on the wear tracks surface, which also contributes to the transition in wear mechanism of AZ31 magnesium alloy induced by HIPIB irradiation.

  17. Simulating transient effects of pulsed beams on beam intercepting devices

    International Nuclear Information System (INIS)

    The development in the physics community towards higher beam power through the possibilities of particle accelerators lead to challenges for the developers of elements which are exposed to effect of particle beams (beam intercepting devices =BIDs). For the design of BIDs, the increasing heat load onto these devices due to energetic and focused beams and - in most cases - their highly pulsed nature has to be taken into account. The physics requirements are sometimes opposed to the current state of the art. As one possibility of many in combining the different aspects for these ambitious demands, two highly developed computer programs, namely FLUKA and ANSYS AUTODYN, were joined for this dissertation. The former is a widely enhanced Monte-Carlo-code which specializes on the interaction of particles with static matter, while the latter is a versatile explicit code for the simulation of highly dynamic processes. Both computer programs were developed intensively over years and are still continuously enhanced in order to achieve their best potential. As a consequence of their separate development histories, their combination requires a large amount of work - at the physics limits of their application as well as at the frontier of computing technology. The current work did not touch all different points needed for a full integration, but it is a first step towards their coupling within a feasible time frame. For the simulation of metallic targets irradiated with highly energetic uranium ions different material models have been combined and one parameter describing the damage of the material was varied. In the case of two copper targets, this procedure led to a qualitative agreement between simulations and experimental results. (author)

  18. Effect of Proton Beam on Cancer Progressive and Metastatic Enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Y. H.; Nam, K. S.; Oh, Y. H.; Kim, M. K.; Kim, M. Y.; Jang, J. S. [Dongguk University, Seoul (Korea, Republic of)

    2008-04-15

    The purpose of this study was to investigate the effect of proton beam on enzymes for promotion/progression of carcinogenesis and metastasis of malignant tumor cells to clarify proton beam-specific biological effects. The changes of cancer chemopreventive enzymes in human colorectal adenocarcinoma HT-29 cells irradiated with proton beams were tested by measuring the activities of quinine reductase (QR), glutathione S-transferase (GST), and ornithine decarboxylase (ODC), glutathione (GSH) levels, and expression of cyclooxygenase-2 (COX-2). We also examined the effect of proton beam on the ODC activity and expression of COX-2 in human breast cancer cell. We then assessed the metastatic capabilities of HT-29 and MDA-MB-231 cells irradiated with proton beam by measuring the invasiveness of cells through Matrigel-coated membrane and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MMP activity in MDA-MB-231 and HT-29 cells. QR activity of irradiated HT-29 cells was slightly increased. Proton irradiation at dose of 32 Gy in HT-29 cells increased GST activity by 1.23-fold. In addition GSH levels in HT-29 cells was significantly increased 1.23- (p<0.05), 1.32- (p<0.01) and 1.34-fold (p<0.01) with the proton irradiation at doses of 8, 16 and 32 Gy, respectively. These results suggest that colon cancer chemopreventive activity was increased with the proton irradiation by increasing QR and GST activities and GSH levels and inhibiting ODC activity. Proton ion irradiation decreased the invasiveness of TPA-treated HT-29 cells and MDA-MB-231 cells through Matrigel-coated membrane. Proton ion irradiation pretreatment decreased TPA-induced MMP activity in MDA-MB-231 and HT-29 cells. Further studies are necessary to investigate if these findings could be translated to in vivo situations

  19. Shaping of Au nanoparticles embedded in various layered structures by swift heavy ion beam irradiation

    Science.gov (United States)

    Dawi, E. A.; ArnoldBik, W. M.; Ackermann, R.; Habraken, F. H. P. M.

    2016-10-01

    We present a novel method to extend the ion-beam induced shaping of metallic nanoparticles in various layered structures. Monodisperse Au nanoparticles having mean diameter of 30 nm and their ion-shaping process is investigated for a limited number of experimental conditions. Au nanoparticles were embedded within a single plane in various layered structures of silicon nitride films (Si3N4), combinations of oxide-nitride films (SiO2-Si3N4) and amorphous silicon films (a-Si) and have been sequentially irradiated at 300 K at normal incidence with 50 and 25 MeV Ag ions, respectively. Under irradiation with heavy Ag ions and with sequential increase of the irradiation fluence, the evolution of the Au peak derived from the Rutherford Backscattering Spectrometry show broadening in Au peak, which indicates that the Au becomes distributed over a larger depth region, indicative of the elongation of the nanoparticles. The latter is observed almost for every layer structure investigated except for Au nanoparticles embedded in pure a-Si matrix. The largest elongation rate at all fluences is found for the Au nanoparticles encapsulated in pure Si3N4 films. For all irradiation energy applied, we again demonstrate the existence of both threshold and saturation fluences for the elongation effects mentioned.

  20. Bronchiolitis obliterans organizing pneumonia after tangential beam irradiation to the breast. Discrimination from radiation pneumonitis

    Energy Technology Data Exchange (ETDEWEB)

    Nambu, Atsushi; Ozawa, Katsura; Kanazawa, Masaki; Miyata, Kazuyuki [Kofu Municipal Hospital (Japan); Araki, Tsutomu; Ohki, Zennosuke [Yamanashi Medical Coll., Tamaho (Japan)

    2002-06-01

    We report a case of bronchiolitis obliterans organizing pneumonia (BOOP) secondary to tangential beam irradiation to the breast, which occurred seven months after the completion of radiotherapy. Although radiation pneumonitis is an alternative consideration, BOOP could be differentiated from it by its relatively late onset and extensive distribution, which did not respect the radiation field. This disease should always be kept in mind in patients with a history of tangential beam irradiation to the breast. (author)

  1. From the coupling between ion beam analysis techniques and physico-chemical characterization methods to the study of irradiation effects on materials behaviour; Du couplage des techniques d'analyse par faisceaux d'ions et des methodes de caracterisation physico-chimique a l'etude des effets d'irradiation sur le comportement des materiaux

    Energy Technology Data Exchange (ETDEWEB)

    Millard-Pinard, N

    2003-07-01

    The general purpose of my research work is to follow and to interpret the surface evolution of materials, which have received several treatments. During my PhD and my post-doc work, my field of research was tribology. Since I arrived in the 'Aval du Cycle Electronucleaire' group of the Institut de Physique Nucleaire de Lyon, my research activities are in line with the CNRS program 'PACE ' (Programme sur l'Aval du Cycle Electronucleaire) within the ACTINET network. They are coordinated by the PARIS (Physico-chimie des actinides et autres radioelements en solution et aux interfaces) and NOMADE (NOuveaux MAteriaux pour les DEchets) GDR with ANDRA (Agence Nationale pour la gestion des Dechets RAdioactifs), EDF and IRSN (Institut de Radioprotection et de Surete Nucleaire) as partner organisations. My work focused on the study of fission products and actinides migration in barrier materials, which may be capable of assuring the long term safety of deep geological repositories. Until now, it was necessary to use the coupling of ion beam analysis techniques and physico-chemical characterization techniques. During the last few months, I have became interested in understanding radiolytic effects. This new orientation has led us to use ion beams as an irradiating tool. These irradiation experiments are pursued in three major projects. The study of cobalt sulfide inhibition effects of radiolysis gas production during the irradiation of model organic molecules. This is a collaboration with the IRSN, the Institut de Recherche sur la Catalyse and the Ecole Nationale Superieure des Mines de Saint-Etienne. A PhD, co-directed by M. Pijolat from ENSMSE and myself, concerning this study will start in October 2003. Water radiolysis effects on iron corrosion are also studied in the particular case of vitrified nuclear waste containers, which will be stored in deep geological repositories. One ANDRA financed PhD, co-directed by Nathalie Moncoffre and myself, is

  2. Radiotherapy in the management of keloids. Clinical experience with electron beam irradiation and comparison with X-ray therapy

    Energy Technology Data Exchange (ETDEWEB)

    Maarouf, M. [Dept. of Radiotherapy, Univ. of Technology (RWTH), Aachen (Germany); Dept. of Stereotactic and Functional Neurosurgery, Univ. of Cologne (Germany); Schleicher, U.; Schmachtenberg, A.; Ammon, J. [Dept. of Radiotherapy, Univ. of Technology (RWTH), Aachen (Germany)

    2002-06-01

    Background: Aim of this study was to evaluate the advantages of electron beam irradiation compared to kilovoltage X-ray therapy in the treatment of keloids. Furthermore, the risk of developing malignancy following keloid radiotherapy was assessed. Patients and Methods: An automatic water phantom was used to evaluate the dose distribution in tissue. Furthermore, a series of measurements was done on the patients using thermoluminescence dosimeters (TLD) to estimate the doses absorbed by the organs at risk. We also report our clinical experience with electron beam radiation of 134 keloids following surgical excision. Results: Electron beam irradiation offers a high control rate (84%) with minimal side effects for keloids. Electron irradiation provides better dose distribution in tissue, and therefore less radiation burden to the organs at risk. After a mean follow-up period of 7.2 years, no severe side effects or malignancies were observed after keloid radiotherapy. Conclusions: Electron radiation therapy is superior to kilovoltage irradiation for treating keloids due to better dose distribution in tissue. In agreement with the literature, no cases of malignancy were observed after keloid irradiation. (orig.)

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

    International Nuclear Information System (INIS)

    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 102 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: D10 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

  4. Measurement of Dose Distributions for Useful Utilization of BioBeam 8000 Gamma Irradiation Device

    International Nuclear Information System (INIS)

    Gamma irradiation device using Cs-137 have been widely utilized to the irradiation of cell, blood, and animal, and the dose measurement and education. Radiation irradiators for cell and blood irradiation used in numerous research institutions has demerits to perform the experiment of large volume objects like as 96 Multiwell Plate. Therefore, KIRAMS (Korea Institute of Radiological and Medical Sciences) introduced Gamma irradiation device having large volume capacity (BioBeam 8000, STS Steuerungstechnik and. Strahlenschutz GmbH, Braunschweig, Germany, Cs137, 3.35 Gy/min). In this study, dose the distribution of newly implemented BioBeam 8000 Gamma irradiation device was measured using glass dosimeter and Gafchromic EBT film dosimetry. In addition, an user guideline for useful utilization of the device based on measurement results are presented

  5. Application of ion beam irradiated ePTFE to repair small vessel injuries

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, N. [Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601 (Japan) and Beam Application Team, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)]. E-mail: norikichi@ionbeams.riken.jp; Suzuki, Y. [Beam Application Team, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Ujiie, H. [Tokyo Women' s Medical University, 8-1 Kawada-cho, Shinjuku, Tokyo 162-8666 (Japan); Hori, T. [Tokyo Women' s Medical University, 8-1 Kawada-cho, Shinjuku, Tokyo 162-8666 (Japan); Iwaki, M. [Beam Application Team, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Yamada, T. [Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601 (Japan)

    2007-04-15

    In surgery, bleeding from small injured vessels often requires prompt hemostasis without occlusion. This study evaluated the usefulness of 0.06 mm thick ion beam irradiated ePTFE sheets to repair small holes in vessels. Both surfaces of ePTFE sheets were irradiated with a 150 keV-Ar{sup +} beam with fluences of 5 x 10{sup 14} ions/cm{sup 2}. A small hole up to 2 mm in diameter was created in the common carotid artery of a rabbit. The defect was wrapped with an ion beam irradiated or non-irradiated ePTFE sheet. Fibrin glue was used to fix the ePTFE sheets to the common carotid artery. Hemostasis was instantly obtained with ion beam irradiated ePTFE but was rather difficult when using a non-irradiated ePTFE sheet. Three weeks after implantation, no occlusion was observed. Histological examination showed that the ePTFE sheets functioned as a scaffold for vessel wall regeneration. Thin ion beam irradiated ePTFE would be useful in vascular surgery.

  6. Mechanisms of defect formation in zinc selenide during impulsed irradiation by powerful subthreshold electron beams

    International Nuclear Information System (INIS)

    Processes of subthreshold defect formation on irradiation of ZnSe by electron pulsed beams having 90ns durtion and 0.2-1.3 J/cm2 energy density in a pulse are studied. Irradiated layers are tested by electron microscopy and photoluminescence methods. 10 refs.; 2 figs

  7. Effects of irradiation on the components of implantable pacemakers

    CERN Document Server

    Kawamura, S; Kuga, N; Shiba, T; Hirose, T; Fujimoto, H; Toyoshima, T; Hyodo, K; Matoba, M

    2003-01-01

    The purpose of this study was to examine the effects of irradiation on implantable pacemaker components. The pacemaker was divided into three components: lead wire and electrode, battery, and electrical circuit, and each component was irradiated by X-ray and electron beams, respectively. The pacemaker parameters were measured by both telemetry data of the programmer and directly measured data from the output terminal. The following results were obtained. For the lead wire and electrode, there was no effect on the pacemaker function due to irradiation by X-ray and electron beams. In the case of battery irradiation, there was no change in battery voltage or current up to 236 Gy X-ray dose. In the electrical circuit, the pacemaker reverted to the regular beating rate (fixed-rate mode) immediately after the start of X-ray irradiation, and it continued in this mode during irradiation. In patients with their own heartbeat rhythm, changing to the fixed-rate mode may cause dangerous conditions such as ventricular fib...

  8. 电子束辐照对泥蚶肉挥发性风味成分的影响%Effect of Electron Beam Irradiation on the Volatile Flavors in Tegillarca Granosa Meat

    Institute of Scientific and Technical Information of China (English)

    杨文鸽; 李超; 徐大伦; 张春芳; 茅宇红

    2012-01-01

    Objective: The effect of electron beam irradiation on the volatile flavors in Tegillarca granosa meat was investigated. Method: The volatile flavors in Tegillarca granosa meat were isolated by solid-phase microextraction and analyzed by gas chromatography/mass spectrometry after irradiation of different doses. Result: 1)After irradiation of 1 9kGy, the sorts of volatile flavors increased from 46 to 55,57,52,58 and 66, respectively. Volatile carbonyl compounds were the principal parts of volatiles, among which ketones made the contribution of sweet flower scent .while some aldehydes provided the lipid-like and fruity aromas. The unusual smell of 7 kGy group samples should be relevant to the abundant volatile carbonyl compounds. 2)The relative content of volatile alcohols increased after irradiation of 3,5 kGy, containing some enols which might make the flavors softer. However, some kinds of olefins could to a certain extent remove the fishy smell. 3)Electron beam irradiation brought about the increases of heterocyclic compounds. Furan contributed to the fruity aromas in Tegillarca granosa meat. Besides, (S-and N-containing compounds including) pyridines and thiazoles provided the flavors of fried meat and nuts. (Compared with the other experimental groups), romatic compounds exhibited the highest relative content with the dose of 5 kGy, among which benzaldehyde had the almond aroma, making the whole flavor of Tegillarca granosa meat better ,to some degree. Conclusion: Electron beam irradiation with the doses of 3-5 kGy produced no significant impact on the original aromas of Tegillarca granosa meat. Furthermore, the irradiation might improve the whole flavors, to some extent%目的:分析电子束辐熙对泥蚶肉挥发性风味成分的影响.方法:以泥蚶为原料,采用固相微萃取-气质联用分析不同剂量电子束辐照后泥蚶肉的挥发性风味成分.结果:1)经1~9 kGy剂量辐照,泥蚶肉挥发性风味成分的种类由46种分别增至55

  9. Effect of xenon on the structural phase state of the surface layer of cemented carbide under pulsed electron-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ovcharenko, Vladimir E., E-mail: ove45@mail.ru [Institute of Strength physics and Materials Science SB RAS, Tomsk, 634055 (Russian Federation); National Research Polytechnic University, Tomsk, 634050 (Russian Federation); Ivanov, Yurii F., E-mail: yufi55@mail.ru [National Research Polytechnic University, Tomsk, 634050 (Russian Federation); High-Current Electronics Institute SB RAS, Tomsk, 634055 (Russian Federation); Mohovikov, Alexey A., E-mail: maa28@rambler.ru [Technological Institute Branch of Tomsk Polytechnic University, Yurga, Kemerovo region, 652055 (Russian Federation); Baohai, Yu, E-mail: bhyu@imr.ac.cn; Cai, Xiaolong, E-mail: xiaolongcai2015@163.com; Zhong, Lisheng, E-mail: zhonglisheng1984@163.com; Xu, Yunhua, E-mail: yunhuaxu2013@163.com [School of Material Science and Engineering, Xi’an University of Technology, Xi’an Shaanxi, 710048 (China)

    2015-10-27

    A comparative analysis of the surface-layer microstructure of a tungsten-based cemented carbide modified with pulsed high-energy electron beams generated by gas-discharge plasmas and of the tool life of metal-cutting plates prepared from this alloy is performed. The choice of a plasma-forming gas providing for the emission of electrons out of the plasma-filled cathode is shown to have a profound influence both on the formation process of nano-sized structural-phase states in the surface layer of the cemented carbide and on the tool life of the metal-cutting plates prepared from this alloy.

  10. Dual beam irradiation of nanostructured FeCrAl oxide dispersion strengthened steel

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.-L., E-mail: chunliang@isu.edu.tw [Department of Materials Science and Engineering, I-Shou University, Kaohsiung 840, Taiwan (China); Richter, A. [Department of Engineering, University of Applied Sciences Wildau (Berlin), Bahnhofstrasse 1, 15745 Wildau (Germany); Koegler, R.; Talut, G. [Institute of Ion Beam Physics and Materials Research, Research Center Dresden-Rossendorf FZD, Bautzner Landstrasse 400, 01328 Dresden (Germany)

    2011-05-31

    Nanostructured ferritic oxide dispersion strengthened (ODS) alloy is an ideal candidate for fission/fusion power plant materials, particularly in the use of a first-wall and blanket structure of a next generation reactor. These steels usually contain a high density of Y-Ti-O and Y-Al-O nanoparticles, high dislocation densities and fine grains. The material contains nanoparticles with an average diameter of 21 nm and was treated by several cold rolling procedures, which modify the dislocation density. Structural analysis with HRTEM shows that the chemical composition of the initial Y{sub 2}O{sub 3} oxide is modified to perovskite YAlO{sub 3} (YAP) and Y{sub 2}Al{sub 5}O{sub 12} garnet (YAG). Irradiation of these alloys was performed with a dual beam irradiation of 2.5 MeV Fe{sup +}/31 dpa and 350 keV He{sup +}/18 appm/dpa. Irradiation causes atomic displacements resulting in vacancy and self-interstitial lattice defects and dislocation loops. Extended SRIM calculations for ODS steel indicate a clear spatial separation between the excess vacancy distribution close to the surface and the excess interstitials in deeper layers of the material surface. The helium atoms are supposed to accumulate mainly in the vacancies. Additionally to structural changes, the effect of the irradiation generated defects on the mechanical properties of the ODS is investigated by nanoindentation. A clear hardness increase in the irradiated area is observed, which reaches a maximum at a close surface region. This feature is attributed to synergistic effects between the displacement damage and He implantation resulting in He filled vacancies. Fine He cavities with diameters of a few nanometers were identified in TEM images.

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

    International Nuclear Information System (INIS)

    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

  12. Evidence for beam self-focusing in the corona of laser-irradiated spherical targets

    International Nuclear Information System (INIS)

    Time integrated photographs have been obtained of the 3/2ω0 harmonic emission from spherical targets irradiated uniformly with a six-beam Nd glass laser system in the ablative mode. Extended filamentary structures are observed which indicate that self-focusing of the incident laser beams in the subcritical density plasma corona is occurring. (author)

  13. Distribution of Energy Deposited in Plastic Tubing and Copper-Wire Insulation by Electron Beam Irradiation

    DEFF Research Database (Denmark)

    Pedersen, Walther Batsberg; Miller, Arne; Pejtersen, K.;

    1978-01-01

    Scanned electron beam treatment is used to improve the physical properties of certain polymers, such as shrinkable plastic tubing and insulated wire and cable. Tubing or wires are passed at high speed under the beam scanner, and the material is irradiated to absorbed doses of several Mrad...

  14. Effects of Ga ion irradiation on growth of GaN on SiN substrates by electron cyclotron resonance-assisted molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Yanagisawa, J. [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531 (Japan) and Center for Quantum Science and Technology under Extreme Conditions, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531 (Japan) and CREST-JST, Kawaguchi Center Building, 4-1-8, Honcho, Kawaguchi, Saitama 332-0012 (Japan)]. E-mail: yanagisawa@ee.es.osaka-u.ac.jp; Matsumoto, H. [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531 (Japan); Fukuyama, T. [Department of Electronics, Information and Communication Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585 (Japan); Shiraishi, Y. [Department of Electronics, Information and Communication Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585 (Japan); Yodo, T. [Department of Electronics, Information and Communication Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585 (Japan); Akasaka, Y. [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531 (Japan)

    2007-04-15

    The possibility of forming GaN layers on Ga-implanted SiN surfaces was investigated using electron cyclotron resonance-assisted molecular beam epitaxy (MBE). It is found that the GaN layer initially formed on the SiN surface by Ga implantation at room temperature was amorphous-like, but become to polycrystalline after annealing at 650 deg. C for 3 min in vacuum. After the MBE growth of GaN, a grain structure of h-GaN was observed on the Ga-implanted SiN surface. The crystallinity of the GaN grown was, however, decreased upon increasing the Ga ion fluence on the SiN surface, which might be due, at least partly, to the formation of Ga clusters by the excess Ga implanted. The present results indicate the possibility of forming patterned GaN layers on SiN by selective Ga implantation on the SiN substrate, using a focused ion beam.

  15. Application of beam irradiation in preparation of visible light responsive TiO2 Films

    Institute of Scientific and Technical Information of China (English)

    HOU Xinggang; LIU Andong

    2007-01-01

    TiO2 films were prepared by sol-gel method.In order to improve the utilization of light, the technologiesof implantation of transition metal ions (V+ and Cr+) and electron beam irradiation to deposit noble metal particles (Ag and Pt) were used. A red shift was found in the spectrum of modified TiO2 films. The photocatalytic experiments showed that the photocatalytic ability under visible light irradiation could be improved dramatically by both the implantation of transition metal and the electron beam irradiation.

  16. Recent Experiments At Ndcx-II: Irradiation Of Materials Using Short, Intense Ion Beams

    CERN Document Server

    Seidl, P A; Persaud, A; Feinberg, E; Ludewigt, B; Silverman, M; Sulyman, A; Waldron, W L; Schenkel, T; Barnard, J J; Friedman, A; Grote, D P; Gilson, E P; Kaganovich, I D; Stepanov, A; Treffert, F; Zimmer, M

    2016-01-01

    We present an overview of the performance of the Neutralized Drift Compression Experiment-II (NDCX-II) accelerator at Berkeley Lab, and summarize recent studies of material properties created with nanosecond and millimeter-scale ion beam pulses. The scientific topics being explored include the dynamics of ion induced damage in materials, materials synthesis far from equilibrium, warm dense matter and intense beam-plasma physics. We summarize the improved accelerator performance, diagnostics and results of beam-induced irradiation of thin samples of, e.g., tin and silicon. Bunches with over 3x10^10 ions, 1- mm radius, and 2-30 ns FWHM duration have been created. To achieve these short pulse durations and mm-scale focal spot radii, the 1.2 MeV He+ ion beam is neutralized in a drift compression section which removes the space charge defocusing effect during final compression and focusing. Quantitative comparison of detailed particle-in-cell simulations with the experiment play an important role in optimizing acc...

  17. Neutron Beam Analysis on Materials for Nuclear Applications, Being Irradiated in Fission Reactors and Having Radioactivity

    International Nuclear Information System (INIS)

    Extensive supports are given from the public sectors to the neutron beam analysis on advanced materials developed mainly in the framework of fundamental solid state physics, through the Japan Atomic Energy Agency and the Institute for Solid State physics in University of Tokyo. However, the related activities are mainly on non-radioactive materials with some limited exceptions, though the facilities for the neutron beam analysis are installed in the radiation controlled areas. Research activities in the field of nuclear related materials have concentrated their efforts for nano structural analysis into the other techniques of the post irradiation examinations, such as the high resolution transmission microscopy, the three dimensional atom probe tomography, and the positron annihilation techniques, than the neutron beam analysis. In the meantime, more detailed analysis on the radiation induced nanostructures are becoming more and more essential for the further understanding of the radiation effects in the materials which will be used in the advanced nuclear systems, such as the nuclear fusion reactors and the generation-IV nuclear fission reactors. Utilizing of the cutting edge techniques for the nanostructural analysis on materials irradiated by neutrons, all of which cannot be installed in the limited area of available hot laboratories, is urgently demanded, of course, satisfying the related legal restrictions and the safety demands. The present study was focused on as the realization of the neutron beam analysis on the nanostructural evolutions of the superconductive materials, which will be used in the ITER, the international thermonuclear experimental reactor, being under construction in Cadarache, France, and the glassy metals, which have some unique and advantageous features for the nuclear applications. (author)

  18. Analytical examination of a spiral beam scanning method for uniform irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Mitsuhiro; Okumura, Susumu; Arakawa, Kazuo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    A new circular beam scanning method for uniform irradiation of high-energy, intense ion beams over a large area has been developed. A sweeping speed and a trajectory density in a radial direction are kept constant to obtain uniform fluence distribution. A radial position of a beam spot on a target and an angular frequency of the circular motion are expressed by an irrational function of time. The beam is swept continuously, and a beam trajectory becomes spiral. More than 90 % uniformity of the fluence distribution can been achieved over a large area. (author)

  19. Influence of E-beam-irradiation on surface modification and micro hardness of recycled polyolefin's

    International Nuclear Information System (INIS)

    Full text: The influence of high (E=5MeV) and low (E=0,125MeV) energy -beam irradiation on bulk and surface modification of recycled polypropylene and polyethylene has been investigated. The new techniques for measuring of polymer surface micro hardness, using decoration of indenter imprint under load lower than 100g are developed. It was shown that e-beam irradiation with high-energy lead to rise of surface micro hardness of recycled polypropylene up to two times for 50g load and 30 percent for 25g load with increasing of irradiation dose (D=100,125,150kGy). The bulk and surface modifications depend on cross-links and oxidation processes in recycled polymer under e-beam irradiation. For low energy e-beam irradiation of recycled polyethylene E=0,125MeV and doses D=50,125 kGy the like results took place. The correlation between increasing of micro hardness of irradiated polymers, E-beam radiation stimulated cross-linkage, oxidation processes by IR (FTIR) Spectroscopy method has been investigated

  20. Biological effects of prenatal irradiation

    International Nuclear Information System (INIS)

    After large releases of radionuclides, exposure of the embryo or fetus can take place by external irradiation or uptake of radionuclies. The embryo and fetus are radiosensitive throughout prenatal development. The quality and extent of radiation effects depend on the development stage. During the preimplantation period (one to 10 days postconception, p.c.) a radiation exposure of at least 0.2 Gy can cause the death of the embryo. Malformations are only observed in rare cases when genetic predisposition exist. Macroscopic, anatomical malformations are induced only after irradiation during the major organogenesis (two to eight weeks p.c.). A radiation dose of about 0.2 Gy is a doubling dose for the malformation risks as extrapolated from experiments with rodents. The human embryo may be more radioresistant. During early fetogenesis (8-15 weeks p.c.) a high radiosensitivity exists for the developmental of the brain. Radiation doses of 1.0 Gy cause severe mental retardation in about 40% of the exposed fetuses. It must be taken into account that a radiation exposure during the fetal period can also induce cancer. It is generally assumed that the risk exists at about the same level as for children. (Author)

  1. In situ electron beam irradiated rapid growth of bismuth nanoparticles in bismuth-based glass dielectrics at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Shiv Prakash; Karmakar, Basudeb, E-mail: basudebk@cgcri.res.in [Central Glass and Ceramic Research Institute (CSIR, India), Glass Science and Technology Section, Glass Division (India)

    2011-09-15

    In this study, in situ control growth of bismuth nanoparticles (Bi{sup 0} NPs) was demonstrated in bismuth-based glass dielectrics under an electron beam (EB) irradiation at room temperature. The effects of EB irradiation were investigated in situ using transmission electron microscopy (TEM), selected-area electron diffraction and high-resolution transmission electron microscopy. The EB irradiation for 2-8 min enhanced the construction of bismuth nanoparticles with a rhombohedral structure and diameter of 4-9 nm. The average particle size was found to increase with the irradiation time. Bismuth metal has a melting point of 271 Degree-Sign C and this low melting temperature makes easy the progress of energy induced structural changes during in situ TEM observations. This is a very useful technique in nano-patterning for integrated optics and other applications.

  2. Kr-86 Ion-Beam Irradiation of Hydrated DNA: Free Radical and Unaltered Base Yields

    OpenAIRE

    Becker, David; Adhikary, Amitava; Tetteh, Smedley T.; Bull, Arthur W.; Sevilla, Michael D.

    2012-01-01

    This work reports an ESR and product analysis investigation of Kr-86 ion-beam irradiation of hydrated DNA at 77 K. The irradiation results in the formation and trapping of both base radicals and sugar phosphate radicals (DNA backbone radicals). The absolute yields (G, μmol/J) of the base radicals are smaller than the yields found in similarly prepared γ-irradiated DNA samples, and the relative yields of backbone radicals relative to base radicals are much higher than that found in γ-irradiate...

  3. Treatment of ships' ballast water by irradiation of pulsed, intense relativistic electron beam

    International Nuclear Information System (INIS)

    Zooplankton contained in ships' ballast water has been successfully treated by irradiation of pulsed, intense relativistic electron beam (PIREB). A treatment chamber is filled up with solution of 3-wt% salt in water containing a larva of artemia as the zooplankton, and is irradiated by the PIREB (2 MeV, 0.4 kA, 140 ns). We have found that electric conductivity and pH of the salt solution does not change significantly within 10 shots of the PIREB irradiation. We have obtained that the artemia of 24% is inactivated by firing 10 shots of the PIREB irradiation. (author)

  4. Structural changes in graphene oxide thin film by electron-beam irradiation

    Science.gov (United States)

    Tyagi, Chetna; Lakshmi, G. B. V. S.; Kumar, Sunil; Tripathi, Ambuj; Avasthi, D. K.

    2016-07-01

    Although we have a whole class of 2D materials, graphene has drawn much attention for its excellent electronic, optical, thermal and mechanical properties. Recent researches have shown its large scale production by the reduction of graphene oxide either thermally, chemically or electrochemically. Although the structure of graphene oxide is inhomogeneous and hence complicated due to the presence of organic moieties e.g. epoxy, carboxylic acid, hydroxyl groups etc., its properties can be tuned by reduction according to desired application. The aim of this work is to synthesize continuous thin film of graphene oxide using commercially available graphene oxide solution and to study its reduction by 25 keV electron beam irradiation at fluences varying from 2 × 1011 to 2 × 1013 e-/cm2. Our studies using X-ray diffraction, Raman microscopy and UV-Vis spectroscopy showed that electron-beam irradiation is an effective tool for reduction of graphene oxide and for tuning its band gap.

  5. Beam tests of proton-irradiated PbWO$_4$ crystals and evaluation of double-sided read-out technique for mitigation of radiation damage effects

    CERN Document Server

    Lucchini, Marco Toliman

    2016-01-01

    The harsh radiation environment in which detectors will have to operate during the High Luminosity phase of the LHC (HL-LHC) represents a crucial challenge for many calorimeter technologies. In the CMS forward calorimeters, ionizing doses and hadron fluences will reach up to 300 kGy (at a dose rate of 30 Gy/h) and $2\\times10^{14}$ cm$^{-2}$, respectively, at the pseudorapidity region of $\\lvert \\eta\\rvert=2.6$. To evaluate the evolution of the CMS ECAL performance in such conditions, a set of PbWO$_4$ crystals, exposed to 24 GeV protons up to integrated fluences between $2.1\\times10^{13}$ cm$^{-2}$ and $1.3\\times10^{14}$ cm$^{-2}$, has been studied in beam tests. A degradation of the energy resolution and a non-linear response to electron showers are observed in damaged crystals. Direct measurements of the light output from the crystals show the amplitude decreasing and pulse becoming faster as the fluence increases. The evolution of the performance of the PbWO$_4$ crystals has been well understood and parame...

  6. In vitro and in vivo ion beam targeted micro-irradiation for radiobiology

    International Nuclear Information System (INIS)

    The main goal of radiobiology is to understand the effects of ionizing radiations on the living. These past decades, ion microbeams have shown to be important tools to study for example the effects of low dose exposure, or the bystander effect. Since 2003, the CENBG has been equipped with a system to perform targeted micro-irradiation of living samples. Recently, microbeams applications on this subject have diversified and the study of DNA repair mechanisms at the cellular and multicellular scales, in vitro and in vivo, has become possible thanks to important evolutions of fluorescence imaging techniques and cellular biology. To take into account these new approaches, the CENBG micro-irradiation beamline has been entirely redesigned and rebuilt to implement new features and to improve the existing ones. My PhD objectives were i) commissioning the facility, ii) characterizing the system on track etch detectors, and on living samples, iii) implementing protocols to perform targeted irradiations of living samples with a con-trolled delivered dose, at the cellular and multicellular scales, and to visualize the early consequences online, iv) modelling these irradiations to explain the biological results using the calculated physical data. The work of these past years has allowed us i) to measure the performances of our system: a beam spot size of about 2 μm and a targeting accuracy of ± 2 μm, and to develop ion detection systems for an absolute delivered dose control, ii) to create highly localized radiation-induced DNA damages and to see online the recruitment of DNA repair proteins, iii) to apply these protocols to generate radiation-induced DNA damages in vivo inside a multicellular organism at the embryonic stage: Caenorhabditis elegans. These results have opened up many perspectives on the study of the interaction between ionizing radiations and the living, at the cellular and multicellular scales, in vitro and in vivo. (author)

  7. Modifications in optical and electrical properties of selenium nanowire arrays using ion beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Narinder [Chaudhary Devi Lal University, Department of Physics, Sirsa (India); Haryana College of Technology and Management, Department of Physics, Kaithal (India); Kumar, Rajesh [RN College of Engineering and Technology, Department of Physics, Madlauda (India); Kumar, Sushil [Chaudhary Devi Lal University, Department of Physics, Sirsa (India); Chakarvarti, S.K. [Manav Rachana International University, Research and Development, Faridabad (India)

    2015-11-15

    In the present paper, 80 MeV Si{sup 7+} ion beam-induced changes in selenium nanowire arrays, fabricated on copper substrates, have been examined. The nanowire arrays were electrodeposited into polymer membranes using template method. The X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and UV-visible spectroscopy have been used to study the ion-induced effects in fabricated nanowire arrays. The XRD and FESEM results confirmed the formation of selenium nanowire arrays with trigonal structures. An intensity variation in the XRD peaks is observed for irradiated nanowires at different ion fluences. The band gap energy of the irradiated nanowire arrays was found to reduce compared with the pristine case. The irradiation of semiconducting selenium nanowires enhances the electrical conductivity. The current-voltage characterizations also confirm an enhancement in electrical conductivity of selenium nanowire arrays with an increase in ion fluence. This study is anticipated to greatly facilitate the design and development of nanodevices-based semiconductor nanowires which can be utilized even in the harsh environment. (orig.)

  8. The network and properties of the NR/SBR vulcanizate modified by electron beam irradiation

    Science.gov (United States)

    Shen, Jing; Wen, Shipeng; Du, Yishi; Li, Ning; Zhang, Liqun; Yang, Yusheng; Liu, Li

    2013-11-01

    A natural rubber/styrene butadiene rubber (NR/SBR) vulcanizate filled with carbon black was modified by high-energy electron beam (EB) irradiation in this work. The crosslinked structure was studied by a special chemical probe method. The influence of EB irradiation on mechanical properties, filler network, and dynamic properties including abrasion resistance, rolling resistance, and wet skid resistance was also investigated. The results revealed that the crosslink structure significantly changed after EB treatment, indicating that the amount of poly- and di-sulfide crosslinked bonds decreased and that of mono-sulfide bonds increased. The polymer-filler interaction was enhanced after EB irradiation. An EB dose of 600 kGy reduced the abrasion loss of the NR/SBR vulcanizate, and one of 300 kGy reduced the rolling resistance by 11.4%. Meanwhile, EB doses below 200 kGy had no obvious effect on the wet skid resistance. This EB-modified NR/SBR vulcanizate can be used to prepare high-performance tires with good abrasion resistance and low rolling resistance.

  9. Modifications in optical and electrical properties of selenium nanowire arrays using ion beam irradiation

    International Nuclear Information System (INIS)

    In the present paper, 80 MeV Si7+ ion beam-induced changes in selenium nanowire arrays, fabricated on copper substrates, have been examined. The nanowire arrays were electrodeposited into polymer membranes using template method. The X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and UV-visible spectroscopy have been used to study the ion-induced effects in fabricated nanowire arrays. The XRD and FESEM results confirmed the formation of selenium nanowire arrays with trigonal structures. An intensity variation in the XRD peaks is observed for irradiated nanowires at different ion fluences. The band gap energy of the irradiated nanowire arrays was found to reduce compared with the pristine case. The irradiation of semiconducting selenium nanowires enhances the electrical conductivity. The current-voltage characterizations also confirm an enhancement in electrical conductivity of selenium nanowire arrays with an increase in ion fluence. This study is anticipated to greatly facilitate the design and development of nanodevices-based semiconductor nanowires which can be utilized even in the harsh environment. (orig.)

  10. Change in magnetic and structural properties of FeRh thin films by gold cluster ion beam irradiation with the energy of 1.67 MeV/atom

    Science.gov (United States)

    Koide, T.; Saitoh, Y.; Sakamaki, M.; Amemiya, K.; Iwase, A.; Matsui, T.

    2014-05-01

    The effect of energetic cluster ion beam irradiation on magnetic and structural properties of FeRh thin films have been investigated. The cluster ions used in the present studies consist of a few gold atoms with the energy of 1.67 MeV/gold atom. Saturation magnetization of the sample irradiated with Au3 cluster ion beam (280 emu/cc) is larger than that for the irradiated sample with Au1 ion beam (240 emu/cc) for the same irradiation ion fluence. These results can also be confirmed by the X-ray magnetic circular dichroism (XMCD) measurement; the XMCD signal for Au3 cluster ion irradiation is larger than that for Au1 ion irradiation. Since the ion beam irradiation induced magnetization of FeRh is significantly correlated with the amount of the lattice defects in the samples, cluster ion beam irradiation can be considered to effectively introduce the lattice defects in B2-type FeRh rather than the single ion beam. Consequently, cluster ion irradiation is better than single ion irradiation for the viewpoint of saturation magnetization, even if the same irradiation energy is deposited in the samples.

  11. Change in magnetic and structural properties of FeRh thin films by gold cluster ion beam irradiation with the energy of 1.67 MeV/atom

    Energy Technology Data Exchange (ETDEWEB)

    Koide, T.; Iwase, A. [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Saitoh, Y. [Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Sakamaki, M.; Amemiya, K. [High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Matsui, T., E-mail: t-matsui@21c.osakafu-u.ac.jp [Research Organization for the 21st Century, Osaka Prefecture University Sakai, Osaka 599-8531 (Japan)

    2014-05-07

    The effect of energetic cluster ion beam irradiation on magnetic and structural properties of FeRh thin films have been investigated. The cluster ions used in the present studies consist of a few gold atoms with the energy of 1.67 MeV/gold atom. Saturation magnetization of the sample irradiated with Au3 cluster ion beam (280 emu/cc) is larger than that for the irradiated sample with Au1 ion beam (240 emu/cc) for the same irradiation ion fluence. These results can also be confirmed by the X-ray magnetic circular dichroism (XMCD) measurement; the XMCD signal for Au3 cluster ion irradiation is larger than that for Au1 ion irradiation. Since the ion beam irradiation induced magnetization of FeRh is significantly correlated with the amount of the lattice defects in the samples, cluster ion beam irradiation can be considered to effectively introduce the lattice defects in B2-type FeRh rather than the single ion beam. Consequently, cluster ion irradiation is better than single ion irradiation for the viewpoint of saturation magnetization, even if the same irradiation energy is deposited in the samples.

  12. EFFECTS OF ELECTRON BEAM IRRADIATION ON ACTIVITIES OF PEROXIDASE CATALASE AND SUPEROXIDE DISMUTASE OF TRIBOLIUM CASTANEURN (HERBST)%电子束辐照对赤拟谷盗保护酶系的影响

    Institute of Scientific and Technical Information of China (English)

    王殿轩; 王晶磊; 李淑荣; 高美须; 徐威; 林敏; 崔莹

    2011-01-01

    By electron beam irradiation, enzyme activity changes of peroxidase (PCD), catalase (CAT), superoxide dis-mutase (SOD) of Triboliian castaneurn (Herbst) in different insects states (3~4th instar larvae, pupae age 1 day to 2 days and adult for 1 day eclosion) have been investigated. The results showed that POD activity of Tribolium castaneum in different states was in order: adult > pupa> larvae; CAT activity: adult > pupa> larvae; SOD activity: larvae > pupa > adult. After irradiation, the protection enzyme activity rose first, then fell with radiation dose increasing. PCX!) of Tribolivan castaneum in three states reached the highest vitality at 500 Gy, CAT of Tribolium castaneum 3-4th instar larvae, pupae age 1 day to 2 days and adult for 1 day eclosion reached the maximum at 420 Gy and 300Gy respectively, SCO of larvae and pupa up to the maximum at 420 Gy, and adult to the highest at 500 Gy. This test would contribute to illuminate the physiological and biochemical effect of electron beam irradiation on stored grain insects.%研究了赤拟谷盗Tribolium castaneurn( Herbst)不同虫态(3~4龄幼虫、1~2龄蛹和羽化1天成虫)体内过氧化物酶( POD)、过氧化氢酶(CAT)、超氧歧化酶(SOD)活力在电子束辐照条件下的变化.结果表明,赤拟谷盗不同虫态的POD活力:羽化1d成虫>1~2龄蛹>3~4龄幼虫;CAT活力:羽化1d成虫>1~2龄蛹>3~4龄幼虫;SOD活力:3~4龄幼虫>1~2龄蛹>羽化1d成虫.辐照处理后,保护酶活力随辐照剂量的增加呈先上升后下降的趋势,赤拟谷盗3种虫态POD活力均在500 Gy辐照剂量最高;3~4龄幼虫和1~2龄蛹CAT活力在420 Gy辐照剂量最高,羽化1d成虫300 Gy最高;3~4龄幼虫和1~2龄蛹SOD活力在420 Gy辐照剂量最高,羽化1d成虫500 Gy最高.本试验结果有助于阐明电子束辐照对储粮害虫的生理生化效应.

  13. Structure and properties of combined protective coatings with use high-current electron beam irradiation

    International Nuclear Information System (INIS)

    Full text: Improvement of superficial materials and products is the important task. The high-efficiency vacuum - arc sources created recently open more ample opportunities for change of properties of a surface of metal materials. Now there is a number of known technologies on drawing coverings for updating a surface of working parts of metals. Today the protecting coatings, which were deposited on tools applied in electrochemical and chemical devices, acquired a great interest. It is known that some kinds of treatment, such as, for example, ion implantation, ion-assisted deposition of thin films, electron beam irradiation, CVD, PVD, etc. cannot result directly in desired effect. Therefore to resolve some application problems, one has to use combined methods of treatment, which allow one to resolve complicated serious problems of material science and industrial fields, for example, in space, automobile, aviation, ship building, etc. So, the goal of this work was to study the structure, element composition and properties of hybrid coatings on TiNi/Cr/Al2O3 and TiN/Al2O3 base, which were deposited on AISI 321 stainless steel before and after electron beam irradiation. A special attention was paid to studies of diffusion and mass-transfer processes. We applied XRD, RBS, AES, SEM with micro-analysis as well as corrosion in sulfur acid, adhesion and hardness tests. It had been demonstrated that these coatings were able to perform different functions as protecting coatings. Tests of TiN/Al2O3 and TiN/Cr/Al2O3 coatings, which were deposited on AISI 321 steel, after high-current electron beam irradiation demonstrated significant increase in corrosion resistance in H2SO4 solution under 4000C temperature. Hardness and adhesion of these coatings to substrate increased, and significant decrease in friction wear of coating surfaces was found. In such a way, in this report it was demonstrated that hybrid coatings on TiN/Cr/Al2O3 and TiN/Al2O3 base after HCEB irradiation under

  14. Electron beam irradiation as a method to modify the wheat starch characteristics

    International Nuclear Information System (INIS)

    Full text: Starch is a renewable bioresource with wide range of potential applications. At present time, considerable efforts are made worldwide with respect to research and mainly to development of processes for treating and modifying of different starches in order to extend their industrial applicability. Our previous work proved the potential of the electron beam irradiation to modify the functional properties of maize starch. The aim of this work is to investigate the possibility to use the electron beam irradiation to change some characteristics of wheat starch. The physicochemical and structural characteristics of the irradiated wheat starch are analyzed in comparison to the native wheat starch ones. The electron beam irradiation lead to the reduction of the paste pH, clarity and apparent viscosity as the absorbed dose increase, while the thermal stability is not affected. Also, changes at the structure level in the irradiated starch can be observed. Electron beam irradiation may be an alternative method to modify some of the wheat starch properties

  15. The changing role of external-beam irradiation in the management of malignant tumors of the major slaivary glands

    International Nuclear Information System (INIS)

    Postoperative irradiation reduces the local recurrence rate for malignant salivary gland tumors. Less extensive surgery followed by immediate radiotherapy is possible without decreasing local control; moreover, cosmetic apperance and physiological function are preserved. Local tumor control was achieved in 16 out of 17 patients without gross tumor using a dose of 6,000 rad/6 wk. Combined photon and electron beams give better cosmetic and functional results than either modality alone. Irradiation with greater than or equal to7,000 rad should be employed in unresectable cases and may effect tumor control

  16. Effects of irradiation on minerals and their consequences in geo-chronology

    International Nuclear Information System (INIS)

    In this HDR (accreditation to supervise research studies) report, the author first gives a brief overview of her scientific approach. Then, addressing the irradiation of minerals by a radioactive source, she discusses the effects of irradiation, notably in the case of monazite, reports an experimental approach of external irradiation by ion beams, and comments some side effects like irradiation of host minerals. She also comments how irradiation-induced damages interfere with some processes like diffusion kinetics and dissolution. She addresses the case of mineral irradiation by means of a femto-second laser source: scientific approach, effects on mineral microstructure, notably in the case of monazite and quartz. The last part discusses issues in abeyance and perspectives in the field of irradiation textures, consequences on the geo-chronological response, alteration mechanisms, role of defects, and contribution of experimental irradiation

  17. Study of Si wafer surfaces irradiated by gas cluster ion beams

    International Nuclear Information System (INIS)

    The surface structures of Si (1 0 0) wafers subjected to gas cluster ion beam (GCIB) irradiation have been analyzed by cross-sectional transmission electron microscopy (XTEM) and atomic force microscopy (AFM). GCIB irradiation is a promising technique for both precise surface etching and planarization of Si wafers. However, it is very important to understand the crystalline structure of Si wafers after GCIB irradiation. An Ar-GCIB used for the physically sputtering of Si atoms and a SF6-GCIB used for the chemical etching of the Si surface are also analyzed. The GCIB irradiation increases the surface roughness of the wafers, and amorphous Si layers are formed on the wafer surface. However, when the Si wafers are annealed in hydrogen at a high temperature after the GCIB irradiation, the surface roughness decreases to the same level as that before the irradiation. Moreover, the amorphous Si layers disappear completely

  18. Stress, microstructure and evolution under ion irradiation in thin films grown by ion beam sputtering: modelling and application to interfacial effects in metallic multilayers; Contraintes, microstructure et sollicitation sous irradiation aux ions de films minces elabores par pulverisation ionique: modelisation et application a l'etude des effets interfaciaux dans des multicouches metalliques

    Energy Technology Data Exchange (ETDEWEB)

    Debelle, A

    2006-09-15

    We have investigated the formation of the interfacial chemical mixing in Mo/Ni multilayers, and particularly the influence of ballistic effects during the growth. For this purpose, hetero-epitaxial b.c.c./f.c.c. Mo(110)/Ni(111) multilayers were grown by two deposition methods: thermal evaporation and direct ion beam sputtering. As a preliminary, an accurate description of the stress state in pure sputtered Mo thin films was required. Microstructural and stress state analyses were essentially carried out by X-ray diffraction, and ion irradiation was used as a powerful tool to control the stress level. We showed that thermal evaporated thin films exhibit a weak tensile growth stress ({approx} 0.6 GPa) that can be accounted for by the grain boundary relaxation model, whereas sputtered thin films develop large compressive growth stress (- 2 to - 4 GPa). This latter results from the bombardment of the growing film by the energetic particles involved during the sputtering process (atomic peening phenomenon), which induces the formation of defects in the layers, generating volume distortions. We thus developed a stress model that includes a hydrostatic stress component to account for these volume strains. This model allowed us to determine the 'unstressed and free of defects lattice parameter' a{sub 0}, solely linked to chemical effects. For epitaxial Mo layers, it was possible to separate coherency stress from growth stress due to their distinct kinetic evolution during ion irradiation. Therefore, the stress analysis enabled us to determine the a{sub 0} values in Mo sub-layers of Mo/Ni superlattices. A tendency to the formation of an interfacial alloy is observed independently of the growth conditions, which suggests that thermodynamic forces favour the exchange mechanism. However, the extent of the intermixing effect is clearly enhanced by ballistic effects. (author)

  19. E-Beam Effects on CMOS Active Pixel Sensors

    International Nuclear Information System (INIS)

    Three different CMOS active pixel structures manufactured in a deep submicron process have been evaluated with electron beam. The devices were exposed to 1 MeV electron beam up to 5kGy. Dark current increased after E-beam irradiation differently at each pixel structure. Dark current change is dependent on CMOS pixel structures. CMOS image sensors are now good candidates in demanding applications such as medical image sensor, particle detection and space remote sensing. In these situations, CISs are exposed to high doses of radiation. In fact radiation is known to generate trapped charge in CMOS oxides. It can lead to threshold voltage shifts and current leakages in MOSFETs and dark current increase in photodiodes. We studied ionizing effects in three types of CMOS APSs fabricated by 0.25 CMOS process. The devices were irradiated by a Co60 source up to 50kGy. All irradiation took place at room temperature. The dark current in the three different pixels exhibits increase with electron beam exposure. From the above figure, the change of dark current is dependent on the pixel structure. Double junction structure has shown relatively small increase of dark current after electron beam irradiation. The dark current in the three different pixels exhibits increase with electron beam exposure. The contribution of the total ionizing dose to the dark current increase is small here, since the devices were left unbiased during the electron beam irradiation. Radiation hardness in dependent on the pixel structures. Pixel2 is relatively vulnerable to radiation exposure. Pixel3 has radiation hardened structure

  20. Study of irradiation effect on curcuma polyphenols

    International Nuclear Information System (INIS)

    The present study was carried out to evaluate the effect of gamma irradiation on curcumin (Curcuma Longa rhizome) component, particularly the polyphenolic fraction. Powdered rhizome was irradiated at 0, 5, 10 and 15 KGy (dose rate of 6 KGy / H). Polyphenolics were extracted and total polyphenols conent (TPC) was quantified using the Folin-Ciocalteau method. The irradiation effect was also evaluated by the HPLC technique. The chromatographic analysis showed that the irradiated and non-irradiated curcumin spectrum gave similar data. The antioxidant and antibacterial activities of the phenolic extracts were also assessed. the anti oxidative potential of the sample was evaluated using two radical scavenging methods with DPPH and ABTS. The antimicrobial analysis showed that the phenolic extracts of curcumin inhibited the growth of the studied microorganisms. Our results showed that irradiated samples were not affected in terms of polyphenols content and characteristics. (Author)

  1. Proton microbeam irradiation effects on PtBA polymer

    Indian Academy of Sciences (India)

    J Kamila; S Roy; K Bhattacharjee; B Rout; B N Dev; R Guico; J Wang; A W Haberl; P Ayyub; P V Satyam

    2006-04-01

    Proton beam lithography has made it possible to make various types of 3D-structures in polymers. Usually PMMA, SU-8, PS polymers have been used as resist materials for lithographic purpose. Microbeam irradiation effects on poly-tert-butyl-acrylate (PtBA) polymer using 2.0 MeV proton microbeam are reported. Preliminary results on pattern formation on PtBA are carried out as a function of fluence. After writing the pattern, a thin layer of Ge is deposited. Distribution of Ge in pristine and ion beam patterned surface of PtBA polymer is studied using the optical and secondary electron microscopic experimental methods.

  2. Anisotropy and Raman absorption of the polyimide surface irradiated by the ion beam for liquid crystal alignment

    International Nuclear Information System (INIS)

    In this paper, polyimide surfaces irradiated by an ion-beam for liquid crystal alignment are investigated by using atomic force microscopy, Raman spectroscopy, and spectroscopic ellipsometry. A liquid crystal cell aligned homogeneously through the ion-beam exposure exhibits electro-optic switching behavior similar to that of a rubbing-aligned liquid crystal cell. However, we found that the surface morphology and bonding molecules of ion-beam-treated polyimide surfaces show properties very different from mechanically-rubbed ones. Experimental results show that optical anisotropy of ion-beam-treated polyimide surfaces results in the formation of hydrogenated amorphous carbon-like structure with a short main-chain, while mechanical rubbing has little effect on structural and compositional variations of polyimide layers

  3. 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.

  4. 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.

  5. Preparation of polymer-coated separators using an electron beam irradiation

    International Nuclear Information System (INIS)

    A polymer-coated polyethylene (PE) separator was prepared by a dip-coating of PVDF-HFP/PEGDMA on both sides of a PE separator followed by an electron beam irradiation. The thermal and electrochemical properties of the polymer-coated PE separator were investigated by using FT-IR, SEM, DSC and an impedance analyzer. The results showed that the coated PVDF-HFP/PEGDMA layer was covalently bound to the PE separator and also crosslinked by an electron beam irradiation. Thermal shrinkage dramatically decreased with an increase in the absorption dose and the PEGDMA content due to the crosslinking of the coated PVDF-HFP/PEGDMA by an irradiation. The PE separator coated with the composition of PVDF-HFP/PEGDMA (9.5/0.5) and irradiated to 150 kGy showed the highest electrolyte uptake of 125% and ionic conductivity of 3.82 x 10-4 S/cm at room temperature.

  6. Irradiation effect on animal feeds and feedstuffs

    International Nuclear Information System (INIS)

    Aiming to secure the safety of animal feeds and develop the new resources, the effect of γ-irradiation on disinfection and the changes in components were investigated. Salmonellae and coliforms contaminating in animal feeds and feedstuffs were eliminated by 0.5 -- 0.6 Mrad and 0.5 -- 0.8 Mrad, and osmophilic moulds were sterilized by 0.7 -- 0.75 Mrad. From these results, it is concluded that the dose for disinfection of animal feeds is 0.8 Mrad. The main components were hardly changed by irradiation up to 5 Mrad, and the component changes in irradiated samples could be suppressed during storage while the components in unirradiated samples were markedly changed with the growth of osmophilic moulds. Histamine and lysinoalanine, which may cause the feed poisoning, were never accumulated in feedstuffs by irradiation. The nutritional value of chick feeds was not changed by 1.0 Mrad irradiation. From these results, it is considered that no problem for wholesomeness of animal feeds occurs by irradiation. Therefore, the irradiation is effective for disinfection and keeping the nutritional value of animal feeds during storage. Irradiation promotes the recovery of proteins in the wastewater by coagulation of proteins and improves the property of coagulants due to the degradation of polysaccharides. These results indicate that irradiation is effective to develop the new resources for animal feeds. (author)

  7. Theoretical study of the effect of the size of a high-energy proton beam of the Large Hadron Collider on the formation and propagation of shock waves in copper irradiated by 450-GeV proton beams

    CERN Document Server

    Ryazanov, A I; Vasilyev, Ya S; Ferrari, A

    2014-01-01

    The interaction of 450GeV protons with copper, which is the material of the collimators of the Large Hadron Collider, has been theoretically studied. A theoretical model for the formation and propagation of shock waves has been proposed on the basis of the anal ysis of the energy released by a proton beam in the electronic subsystem of the material owing to the deceleration of secondary particles appearing in nuclear reactions induced by this beam on the electronic subsy stem of the material. The subsequent transfer of the energy from the excited electronic subsystem to the crystal lattice through the electron–phonon interaction has been described within the thermal spike model [I.M. Lifshitz, M.I. Kaganov, and L.V. Tanatarov, Sov. Phys. JETP 4 , 173 (1957); I.M. Lifshitz, M.I. Kaganov, and L.V. Tanatarov, At. Energ. 6 , 391 (1959); K. Yasui, Nucl. Instrum. Methods Phys. Res., Sect. B 90 , 409 (1994)]. The model of the formation of shock waves involves energy exchange processes between excited electronic an...

  8. Individualized eye shields for use in electron beam therapy as well as low-energy photon irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Asbell, S.O.; Siu, J.; Lightfoot, D.A.; Brady, L.W.

    1980-04-01

    Thin lead eye shields formed with a rubber hammer over smooth wooden mandril and coated with dental acrylic have been used on 25 patients undergoing electron beam treatment for mycosis fungoides or superficial x-ray irradiation with no significant difficulties. The shields may be fabricated in less than two hours and exactly fit the contour and size of the eye. Details of the fabrication process and evaluation of the shielding effectiveness are presented.

  9. One-step synthesis of high conductivity silver nanoparticle-reduced graphene oxide composite films by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Gang; Wang, Yujia; Pu, Xianjuan; Jiang, Yong; Cheng, Lingli, E-mail: chenglingli@shu.edu.cn; Jiao, Zheng, E-mail: zjiao@shu.edu.cn

    2015-09-15

    Graphical abstract: - Highlights: • Both graphene oxide and silver ion were reduced simultaneously by electron beam-based method. • The size of AgNPs can be controlled by changing the irradiation dose of electron beam. • The AgNPs/rGO nanocomposite exhibits much lower sheet resistivity (0.06 Ω m). - Abstract: A rapid, eco-friendly, one-step electron beam (EB)-based method for both the reduction of graphene oxide and loading of Ag nanoparticles (AgNPs) were achieved. Further, the effects of irradiation dose on the morphology of AgNPs and the sheet resistance of Ag nanoparticles/reduced graphene oxide (AgNPs/rGO) were studied. The results reveal that when the irradiation dose increased from 70 kGy to 350 kGy, the size of the AgNPs decreased and became uniformly distributed over the surface of the rGO nanosheets. However the size of the AgNPs increased when the irradiation dose reached 500 kGy. Four-point probe measurement showed that the sheet resistance of the AgNPs/rGO films decreased with decreasing AgNPs size. The lowest sheet resistivity of 0.06 Ω m was obtained in the film corresponding to 350 kGy irradiation dose, which showed a much lower resistivity than the GO film (5.04 × 10{sup 5} Ω m). The formation mechanisms of the as-prepared AgNPs/rGO nanocomposites were proposed. This study provides a fast and eco-friendly EB irradiation induced method to controlling the dimensions of AgNPs/rGO nanocomposites, which can strongly support the mass production of AgNPs/rGO nanocomposites for practical applications.

  10. Size-dependent crystalline fluctuation and growth mechanism of bismuth nanoparticles under electron beam irradiation

    Science.gov (United States)

    Wu, Sujuan; Jiang, Yi; Hu, Lijun; Sun, Jianguo; Wan, Piaopiao; Sun, Lidong

    2016-06-01

    Advanced nanofabrication requires accurate tailoring of various nanostructures with the assistance of electron or ion beam irradiation. However, evolution of the nanostructures under the beam irradiation significantly affects the fabrication process. It is thus of paramount importance to study the evolution behaviors and growth mechanism of the nanostructures. In this study, bismuth nanoparticles were selected to investigate crystalline fluctuation under electron beam irradiation via transmission electron microscopy. The results disclose size-dependent crystalline fluctuation of the nanoparticles. The particles exhibit crystalline and non-crystalline features for sizes of above 15 and below 4 nm, respectively, while a mixture of the two states is observed with sizes in between. The crystalline fluctuation facilitates the growth process of the particles when a crystalline particle is in contact with another non-crystalline one. This is promising for applications in nanofabrication where high quality interfaces are desired between two joining parts.Advanced nanofabrication requires accurate tailoring of various nanostructures with the assistance of electron or ion beam irradiation. However, evolution of the nanostructures under the beam irradiation significantly affects the fabrication process. It is thus of paramount importance to study the evolution behaviors and growth mechanism of the nanostructures. In this study, bismuth nanoparticles were selected to investigate crystalline fluctuation under electron beam irradiation via transmission electron microscopy. The results disclose size-dependent crystalline fluctuation of the nanoparticles. The particles exhibit crystalline and non-crystalline features for sizes of above 15 and below 4 nm, respectively, while a mixture of the two states is observed with sizes in between. The crystalline fluctuation facilitates the growth process of the particles when a crystalline particle is in contact with another non

  11. Ion-irradiated polymer studied by a slow positron beam

    International Nuclear Information System (INIS)

    Poly (aryl-ether-ether ketone) (PEEK) films were irradiated with 1MeV and 2MeV 0+ ions and the positron annihilation Doppler broadening was measured as a function of the positron energy. The annihilation lines recorded at relatively low positron energies were found to become broader with increasing the irradiation dose, suggesting that positronium (Ps) formation may be inhibited in the damaged regions. A correlation was observed between the Doppler broadening and spin densities determined by electron spin resonance (ESR). (author)

  12. Cavity Formation in Aluminium Irradiated with a Pulsating Beam of 225 MeV Electrons

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Bilde-Sørensen, Jørgen; Leffers, Torben;

    1984-01-01

    High-purity aluminium was irradiated with a pulsating beam of 225 MeV electrons to a maximum dose of 0.035 dpa with a helium generation rate of up to 17 appm/dpa. The irradiated samples contained cavities in the size range 5 to 70 nm. In a zone of up to 14 μm from the grain boundaries cavity size...

  13. Effect of irradiation on the streptococcus mutans

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Ki Dong; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Kyung Hee Univ., Seoul (Korea, Republic of)

    2007-03-15

    To observe direct effect of irradiation on cariogenic Streptococcus mutans. S. mutans GS5 was exposed to irradiation with a single absorbed dose of 10, 20, 30, and 40 Gy. Viability and changes in antibiotic sensitivity, morphology, transcription of virulence factors, and protein profile of bacterium after irradiation were examined by pour plate, disc diffusion method, Transmission electron microscopy. RT-PCR, and SDS-PAGE, respectively. After irradiation with 10 and 20 Gy, viability of S. mutans was reduced. Further increase in irradiation dose, however, did not affect the viability of the remaining cells of S. mutans. Irradiated S. mutans was found to have become sensitive to antibiotics. In particular, the bacterium irradiated with 40 Gy increased its susceptibility to cefotaxime, penicillin, and tetracycline. Under the transmission electron microscope, number of morphologically abnormal cells was increased as the irradiation dose was increased. S. mutans irradiated with 10 Gy revealed a change in the cell wall and cell membrane. As irradiation dose was increased. a higher number of cells showed thickened cell wall and cell membrane and lysis, and appearance of ghost cells was noticeable. In RT-PCR, no difference was detected in expression of gtfB and spaP between cells with and without irradiation of 40 Gy. In SDS-PAGE, proteins with higher molecular masses were gradually diminished as irradiation dose was increased. These results suggest that irradiation affects the cell integrity of S. mutans, as observed by SDS-PAGE, and as manifested by the change in cell morphology, antibiotic sensitivity, and eventually viability of the bacterium.

  14. Comparison and fitting of several Global-to_beam irradiance models in Spain

    OpenAIRE

    Pagola, Íñigo; Gastón, Martín; Fernández-Peruchena, Carlos M.; Torres, Jose Luis; Silva, Manuel; Ramírez, Lourdes

    2009-01-01

    In this paper, a comparison of different global to beam irradiance models has been performed. In a first step, five global-to-beam irradiance models are compared against ground measurements from three sites in Spain. Four of these existing models have also been fitted in the selected sites, and the results are presented as well. Finally, one new model (fully described in paper 11693) is also compared with the same ground measurements. The model comparison has been made by means of first and s...

  15. Electrical and optoelectrical modification of cadmium sulfide nanobelts by low-energy electron beam irradiation

    Science.gov (United States)

    Zhang, Lijie; Liu, Manman; Zhao, Mei; Dong, Youqing; Zou, Chao; Yang, Keqin; Yang, Yun; Huang, Shaoming; Zhu, Da-Ming

    2016-09-01

    In this report, we describe a method for modifying electrical and optoelectrical properties of CdS nanobelts using low-energy (lower than 10 keV) e-beam irradiation in a scanning electron microscope. The electrical conductivity of the nanobelts was dramatically improved via the irradiation of e-beams. The modified conductivity of the nanobelts depends on the energy of the e-beam; it exhibits a larger photocurrent and higher external quantum efficiency but slower time-response than that before the modification. A possible mechanism about the modification is the increase of electron accumulation (injected electrons) in the nanobelts due to e-beam irradiation. In addition, the optoelectrical modification could be caused by the trapped electrons in the nanobelts and the decrease of contact resistance between the nanobelts and metal electrodes induced by e-beam irradiation. The results of this work are significant for the in situ study of semiconductor nanostructures in the electron microscope. Besides, the method of electrical and optoelectrical modification presented here has potential application in electronics and optoelectronics.

  16. Quality of 'Climax' blueberries after low dosage electron beam irradiation

    International Nuclear Information System (INIS)

    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. Removal of diclofenac from surface water by electron beam irradiation combined with a biological aerated filter

    Science.gov (United States)

    He, Shijun; Wang, Jianlong; Ye, Longfei; Zhang, Youxue; Yu, Jiang

    2014-12-01

    The degradation of DCF was investigated in aqueous solution by using electron beam (EB) technology. When the initial concentration was between 10 and 40 mg/L, almost 100% of the DCF was degraded at a dose of 0.5 kGy. However, only about 6.5% of DCF was mineralized even at 2 kGy according to total organic carbon (TOC) measurements. A combined process of EB and biological aerated filter (BAF) was therefore developed to enhance the treatment of DCF contaminated surface water. The effluent quality of combined process was substantially improved by EB pretreatment due to the degradation of DCF and related intermediates. Both irradiation and biological treatment reduced the toxicity of the treated water. The experimental results showed that EB is effective for removing DCF from artificial aqueous solution and real surface water.

  18. 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)

  19. Large scale silver nanowires network fabricated by MeV hydrogen (H+) ion beam irradiation

    Science.gov (United States)

    Honey, S.; Naseem, S.; Ishaq, A.; Maaza, M.; Bhatti, M. T.; Wan, D.

    2016-04-01

    A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H+) ion beam irradiation. Ag-NWs are irradiated under H+ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H+ ion beam-induced welding of Ag-NWs at intersecting positions. H+ ion beam induced welding is confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, the structure of Ag NWs remains stable under H+ ion beam, and networks are optically transparent. Morphology also remains stable under H+ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H+ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps: ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices. Project supported by the National Research Foundation of South Africa (NRF), the French Centre National pour la Recherche Scientifique, iThemba-LABS, the UNESCO-UNISA Africa Chair in Nanosciences & Nanotechnology, the Third World Academy of Science (TWAS), Organization of Women in Science for the Developing World (OWSDW), the Abdus Salam ICTP via the Nanosciences African Network (NANOAFNET), and the Higher Education Commission (HEC) of Pakistan.

  20. Zenithal alignment of liquid crystal on homeotropic polyimide film irradiated by ion beam

    OpenAIRE

    Choi, Yoonseuk; Yoon, Tae-Hoon; Kwon, Jin Hyuk; Yi, Jonghoon; Gwag, Jin Seog

    2012-01-01

    We investigate the pretilt characteristics of a nematic liquid crystal [LC] in terms of ion beam exposure conditions on the homeotropic polyimide alignment layer. The pretilt angle of LCs in the case of high-energy ion beam treatment was decreased considerably almost the same to that of the homogenous alignment layer though we used homeotropic polyimide film at first. Increasing irradiating energy, we could control the pretilt from 90° to 1° with several steps. We believe that this is because...

  1. Toxicity reduction for pharmaceuticals mixture in water by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Boiani, Nathalia Fonseca; Tominaga, Flavio Kiyoshi; Borrely, Sueli Ivone, E-mail: flavio_tominaga@hotmail.com, E-mail: sborrely@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The incorrect disposal of products is committing the environment quality once the aquatic environment is the main vehicle for dispersion of pollutants. Among the highlighted contaminants there are the pharmaceuticals, which are also released to the aquatic environment through the domestic sewage, hospitals and effluents. The monitoring of these pharmaceuticals in the environment has grown, showing many of them as persistent pollutants. Pharmaceuticals from different therapeutic classes have been detected in domestic sewage, surface water and groundwater around the world. Several studies evidenced Fluoxetine Hydrochloride residues in waters. Another important product is the Propranolol, used for heart disease treatments as far as fluoxetine is applied for treating mental diseases. The objective of this study was to apply the radiation processing for the abatement of pollutant in waters. Electron beam accelerator was used during irradiation of the mixture (Propranolol + Fluoxetine Hydrochloride) in aqueous solution. Acute toxicity assays were carried out for Vibrio fischeri marine bacterium, 15 minutes exposure. The results showed that irradiation (2.5kGy and 5.0kGy) enhanced the average effective concentration of the mixture, which means reduction of toxicity (56.34%, 55.70% respectively). Inverse effect was obtained with 7.5 kGy and 10 kGy. (author)

  2. Remotion of organic compounds of actual industrial effluents by electron beam irradiation

    Science.gov (United States)

    Sampa, M. H. O.; Duarte, C. L.; Rela, P. R.; Somessari, E. S. R.; Silveira, C. G.; Azevedo, A. L.

    1998-06-01

    Organic compounds has been a great problem of environmental pollution, the traditional methods are not effecient on removing these compounds and most of them are deposited to ambient and stay there for long time causing problems to the environment. Ionizing radiation has been used with success to destroy organic molecules. Actual industrial effluents were irradiated using IPEN's electron beam wastewater pilot plant to study organic compounds degradation. The samples were irradiated with and without air mixture by different doses. Irradiation treatment efficiency was evaluated by the Cromatography Gas Analyses of the samples before and after irradiation. The studied organic compounds were: phenol, chloroform, tetrachloroethylene (PCE), carbon tetrachloride, trichloroethylene (TCE), 1,1-dichloroethane, dichloromethane, benzene, toluene and xilene. A degradation superior to 80% was achieved for the majority of the compounds with air addition and 2kGy delivered dose condition. For the samples that were irradiated without air addition the degradation was higher.

  3. Remotion of organic compounds of actual industrial effluents by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sampa, M.H.O.; Duarte, C.L.; Rela, P.R.; Somessari, E.S.R.; Silveira, C.G.; Azevedo, A.L

    1998-06-01

    Organic compounds has been a great problem of environmental pollution, the traditional methods are not efficient on removing these compounds and most of them are deposited to ambient and stay there for long time causing problems to the environment. Ionizing radiation has been used with success to destroy organic molecules. Actual industrial effluents were irradiated using IPEN's electron beam wastewater pilot plant to study organic compounds degradation. The samples were irradiated with and without air mixture by different doses. Irradiation treatment efficiency was evaluated by the Cromatography Gas Analyses of the samples before and after irradiation. The studied organic compounds were: phenol, chloroform, tetrachloroethylene (PCE), carbon tetrachloride, trichloroethylene (TCE), 1,1-dichloroethane, dichloromethane, benzene, toluene and xilene. A degradation superior to 80% was achieved for the majority of the compounds with air addition and 2kGy delivered dose condition. For the samples that were irradiated without air addition the degradation was higher.

  4. Remotion of organic compounds of actual industrial effluents by electron beam irradiation

    International Nuclear Information System (INIS)

    Organic compounds has been a great problem of environmental pollution, the traditional methods are not efficient on removing these compounds and most of them are deposited to ambient and stay there for long time causing problems to the environment. Ionizing radiation has been used with success to destroy organic molecules. Actual industrial effluents were irradiated using IPEN's electron beam wastewater pilot plant to study organic compounds degradation. The samples were irradiated with and without air mixture by different doses. Irradiation treatment efficiency was evaluated by the Cromatography Gas Analyses of the samples before and after irradiation. The studied organic compounds were: phenol, chloroform, tetrachloroethylene (PCE), carbon tetrachloride, trichloroethylene (TCE), 1,1-dichloroethane, dichloromethane, benzene, toluene and xilene. A degradation superior to 80% was achieved for the majority of the compounds with air addition and 2kGy delivered dose condition. For the samples that were irradiated without air addition the degradation was higher

  5. Projected beam irradiation at low latitudes using Meteonorm database

    DEFF Research Database (Denmark)

    Hatwaambo, Sylvester; Perers, Bengt; Karlsson, Björn

    2009-01-01

    The quantitative analysis of beam radiation received on a solar concentrator may be understood by evaluating the projected solar height angle or profile angle along the north-south vertical plane. This means that all the sunrays projected along the north-south vertical plane will be intercepted...... radiation data is missing or irregular. In this paper we present the projected beam solar radiation at low latitudes based on the standard Meteonorm calculations. The conclusion is that there is potential in using solar concentrators at these latitudes since the projected beam radiation is more during...... by a collector provided the projection angle lies within the acceptance angle. The Meteonorm method of calculating solar radiation on any arbitrary oriented surface uses the globally simulated meteorological databases. Meteonorm has become a valuable too for estimating solar radiation where measured solar...

  6. Broad-beam three-dimensional irradiation system for heavy-ion radiotherapy at HIMAC

    CERN Document Server

    Futami, Y; Fujita, M; Tomura, H; Higashi, A; Matsufuji, N; Miyahara, N; Endo, M; Kawachi, K

    1999-01-01

    A three-dimensional irradiation system using a broad beam has been installed for heavy-ion cancer therapy at the Heavy Ion Medical Accelerator in Chiba (HIMAC) facility. Only the target region is irradiated at the 100% dose level; the dose level at other parts of irradiated tissues is less, using a range shifter, a multileaf collimator and a compensator. The devices are the same as those used in two-dimensional irradiation, except that the setting values of the devices can be dynamically changed during the treatment. The thickness of the absorber and the aperture of the multileaf collimator are dynamically controlled during irradiation, so that the Bragg peak is swept in the depth direction and the Bragg peak outside of the target volume is blocked by the multileaf collimator. The performance of this system was checked by irradiation of a phantom using a 290 MeV/nucleon carbon beam. The dose distribution realized by this three-dimensional irradiation agreed satisfactorily with the planned one.

  7. Biological Effects after Prenatal Irradiation

    International Nuclear Information System (INIS)

    A Task Group of the International Commission on Radiological Protection (ICRP) has finished a report Biological Effects after Prenatal Irradiation (Embryo and Fetus) which has been approved by the Main Commission and Will be Published. Some new important scientific data shall be discussed in this contribution. During the preimplantation period lethality of the mammalian embryo is the dominating radiation effect. However, in mouse strains with genetic predispositions it has been shown that also malformations can be caused. This effect is genetically determined and its mechanisms is different from the induction of malformations during major organogenesis. Radiation exposures during this prenatal period leads ato an increase of genomic instability of cells in the normal appearing fetuses. These radiation effects can be transmitted to the next generation. A renewed analysis of individuals with severe mental retardation after exposures during the 8th to 15th week post conception in Hiroshima and Nagasaki gives evidence that a threshold dose exists for this effect around 300 mGy. This is supported by a number of experimental animal data which have been obtained from cellular and molecular investigations during the brain development. The data show the high radiosensitivity of the developing brain but also the various compensatory mechanisms and the enormous plasticity of these processes. The radiosensitivity varies strongly during the prenatal development. The highest sensitivity is found during the early and mid fetal period which is coinciding with weeks 8-15 post conception in humans. The lowest doses causing persistent damage are in the range of 100 to 300 mGy. For intelligence quotient scores a linear dose response model provides a satisfactory fit. From the experimental data it can be concluded that the fetal stage is most sensitive to the carcinogenic effect in comparison to the other prenatal stages. Such as clear situation cannot be obtained from the

  8. Treatment test of supernatant from sewage sludge by irradiation of high energy electron beams under supersaturation with oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Hosono, Masakazu; Arai, Hidehiko (Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment); Aizawa, Masaki; Shimooka, Toshio; Yamamoto, Ichiro; Shimizu, Ken; Sugiyama, Masashi.

    1993-02-01

    Supernatant comes from dewaterization of sewage sludge, and contains biologically nondegradable organics. Therefore, it is hard to be treated by conventional activated sludge method. The development of a new technology is required to decrease the chemical oxygen demand (COD) effectively below 30 mg/l. Irradiation of high energy electron beams can convert nondegradable organics in water into substances which are biodegradable. However, sufficient dissolved oxygen in water is needed to induce oxidation effectively. In the present study, the treatment of supernatant was studied using an apparatus which can be irradiated by high intensity electron beams in flow system under supersaturation with oxygen by pressurization up to 3 atms. The dependence of oxygen concentration on the reduction in absorbance at 230 nm of azo dye (Acid Red 265) aqueous solution was examined, and it was clarified that sufficient oxygen was supplied in the solution up to about 14 kGy under 3 atms of oxygen. Radiation treatment of supernatant which came from the leather works was carried out using the above apparatus. However, as this supernatant contained high concentration of nitrite, the nitrite was removed by limited aeration activated sludge method. By this pretreatment, COD was reduced from 200 mg/l to 53 mg/l. Then, the biodegradability of supernatant irradiated under supersaturation with oxygen was examined. The final COD of the supernatant was reduced below 30 mg/l by the combined method of irradiation of 7 kGy and biological treatment. (author).

  9. Ionic liquids influence on the surface properties of electron beam irradiated wood

    Energy Technology Data Exchange (ETDEWEB)

    Croitoru, Catalin [“Transilvania” University of Brasov, Product Design and Environment Department, 29 Eroilor Str., 500036, Brasov (Romania); Patachia, Silvia, E-mail: st.patachia@unitbv.ro [“Transilvania” University of Brasov, Product Design and Environment Department, 29 Eroilor Str., 500036, Brasov (Romania); Doroftei, Florica; Parparita, Elena; Vasile, Cornelia [“Petru Poni” Institute of Macromolecular Chemistry, Physical Chemistry of Polymers Department, 41A Gr. Ghica Voda Alley, Iasi (Romania)

    2014-09-30

    Highlights: • Wood veneers impregnated with three imidazolium-based ionic liquids and irradiated with electron beam were studied by FTIR-ATR, SEM/EDX, AFM, contact angle and image analysis. • ILs preserve the surface properties of the wood (surface energy, roughness, color) upon irradiation, in comparison with the reference wood, but the surface composition is changed by treatment with IL-s, mainly with 1-butyl-3-methylimidazolium tetrafluoroborate. • Under electron beam irradiation covalent bonding of the imidazolium moiety to wood determines a higher resistance to water penetration and spreading on the surface. - Abstract: In this paper, the influence of three imidazolium-based ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-hexyl-3-methylimidazolium chloride) on the structure and surface properties of sycamore maple (Acer pseudoplatanus) veneers submitted to electron beam irradiation with a dose of 50 kGy has been studied by using Fourier transform infrared spectroscopy, as well as image, scanning electron microscopy/SEM/EDX, atomic force microscopy and contact angle analysis. The experimental results have proven that the studied ionic liquids determine a better preservation of the structural features of wood (cellulose crystallinity index and lignin concentration on the surface) as well as some of surface properties such as surface energy, roughness, color upon irradiation with electron beam, in comparison with the reference wood, but surface composition is changed by treatment with imidazolium-based ionic liquids mainly with 1-butyl-3-methylimidazolium tetrafluoroborate. Also, under electron beam irradiation covalent bonding of the imidazolium moiety to wood determines a higher resistance to water penetration and spreading on the surface.

  10. 2H-SiC Dendritic Nanocrystals In Situ Formation from Amorphous Silicon Carbide under Electron Beam Irradiation

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Under electron beam irradiation, the in-situ formation of 2H-SiC dentritic nanocrystals from amorphous silicon carbide at room temperature was observed. The homogenous transition mainly occurs at the thin edge and on the surface of specimen where the energy obtained from electron beam irradiation is high enough to cause the amorphous crystallizing into 2H-SiC.

  11. Target volume delineation in external beam partial breast irradiation: less inter-observer variation with preoperative- compared to postoperative delineation

    NARCIS (Netherlands)

    Leij, F. van der; Elkhuizen, P.H.M.; Janssen, T.M.; Poortmans, P.M.P.; Sangen, M. van der; Scholten, A.N.; Vliet-Vroegindeweij, C. van; Boersma, L.J.

    2014-01-01

    The challenge of adequate target volume definition in external beam partial breast irradiation (PBI) could be overcome with preoperative irradiation, due to less inter-observer variation. We compared the target volume delineation for external beam PBI on preoperative versus postoperative CT scans of

  12. Evaluation by citogenetic methods of the efficiency of irradiating human cells by the therapeutic proton beam of the JINR Phasotron

    International Nuclear Information System (INIS)

    The effectiveness of therapeutic proton beam on human cells is evaluated against the criterion of formation of chromosome aberrations in human blood lymphocytes. Both physical characteristics of protons (LET at the place of entry and in the modified Bragg peak region) and the biological factor: differences in the radiosensitivity of non-dividing cells of normal tissues along the beam path and dividing cells of tumors were taken into account. Proton RBE is ∼ 1 at the beam entry into the object and ∼ 1.2 in the Bragg peak region. Allowing for a higher radiosensitivity of dividing cells in the G2 phase of the cell cycle, irradiation effectiveness is found to increase up to ∼1.4

  13. Study on application of the physical detection methods for electron beam-irradiated agricultural products

    International Nuclear Information System (INIS)

    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 (T2) in black pepper, raisin, and beef seasoning and intermediates values of T1-T2 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

  14. HiRadMat: A high‐energy, pulsed beam, material irradiation facility

    CERN Multimedia

    Charitonidis, Nikolaos

    2016-01-01

    HiRadMat is a facility constructed in 2011, designed to provide high-intensity pulsed beams to an irradiation area where different material samples or accelerator components can be tested. The facility, located at the CERN SPS accelerator complex, uses a 440 GeV proton beam with a pulse length up to 7.2 μs and a maximum intensity up to 1E13 protons / pulse. The facility, a unique place for performing state-of-the art beam-to-material experiments, operates under transnational access and welcomes and financially supports, under certain conditions, experimental teams to perform their experiments.

  15. Heavy ion irradiation effects of polymer film on absorption of light

    Energy Technology Data Exchange (ETDEWEB)

    Kasai, Noboru; Seguchi, Tadao [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Arakawa, Tetsuhito

    1997-03-01

    Ion irradiation effects on the absorption of light for three types of polymer films; polyethylene-terephthalate (PET), polyethylene-naphthalate (PEN), and polyether-ether-ketone (PEEK) were investigated by irradiation of heavy ions with Ni{sup 4+}(15MeV), O{sup 6+}(160MeV), and Ar{sup 8+}(175MeV), and compared with electron beams(EB) irradiation. The change of absorption at 400nm by a photometer was almost proportional to total dose for ions and EB. The absorption per absorbed dose was much high in Ni{sup 4+}, but rather small in O{sup 6+} and Ar{sup 8+} irradiation, and the absorption by EB irradiation was accelerated by the temperature of polymer film during irradiation. The beam heating of materials during ion irradiation was assumed, especially for Ni ion irradiation. The heavy ion irradiation effect of polymers was thought to be much affected by the ion beam heating than the linear energy transfer(LET) of radiation source. (author)

  16. Application of the in-beam PET therapy monitoring on precision irradiations with helium ions

    International Nuclear Information System (INIS)

    The main goal of the present dissertation was to extend the in-beam PET method to new ion types. It was shown that the in-beam PET method can also be applied for 3He irradiations. For this experiments on a 3He beam were performed. The activity yield is at equal applied dose about three times larger than at 12C irradiations. The reachable range resolution is smaller than 1 mm. At the irradiation of an inhomogeneous phantom it was shown that a contrast between different materials is resolvable. From the experimentally determined reaction rates cross sections for the reactions leading to positron emitters were performed. The data taken in the 3He experiments were compared those obtained in carbon-ion experiments as well as literature data for proton irradiations. A comparison with the calculations of the simulation program SHIELD-HIT was performed. A collection of cross-section models and the established requirements for a simulation program applicable for in-beam PET are preparing for further work

  17. Influence of electron beam irradiation on physicochemical properties of poly(trimethylene carbonate)

    NARCIS (Netherlands)

    Jozwiakowska, Joanna; Wach, Radoslaw A.; Rokita, Bozena; Ulanski, Piotr; Nalawade, Sameer P.; Grijpma, Dirk W.; Feijen, Jan; Rosiak, Janusz M.

    2011-01-01

    Electron beam (EB) irradiation of poly(trimethylene carbonate) (PTMC), an amorphous, biodegradable polymer used in the field of biomaterials, results in predominant cross-linking and finally in the formation of gel fraction, thus enabling modification of physicochemical properties of this material w

  18. New electron beam facility for irradiated plasma facing materials testing in hot cell

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, N.; Kawamura, H. [Oarai Research Establishment, Ibaraki-ken (Japan); Akiba, M. [Naka Research Establishment, Ibaraki-ken (Japan)

    1995-09-01

    Since plasma facing components such as the first wall and the divertor for the next step fusion reactors are exposed to high heat loads and high energy neutron flux generated by the plasma, it is urgent to develop of plasma facing components which can resist these. Then, we have established electron beam heat facility ({open_quotes}OHBIS{close_quotes}, Oarai Hot-cell electron Beam Irradiating System) at a hot cell in JMTR (Japan Materials Testing Reactor) hot laboratory in order to estimate thermal shock resistivity of plasma facing materials and heat removal capabilities of divertor elements under steady state heating. In this facility, irradiated plasma facing materials (beryllium, carbon based materials and so on) and divertor elements can be treated. This facility consists of an electron beam unit with the maximum beam power of 50kW and the vacuum vessel. The acceleration voltage and the maximum beam current are 30kV (constant) and 1.7A, respectively. The loading time of electron beam is more than 0.1ms. The shape of vacuum vessel is cylindrical, and the mainly dimensions are 500mm in inner diameter, 1000mm in height. The ultimate vacuum of this vessel is 1 x 10{sup -4}Pa. At present, the facility for thermal shock test has been established in a hot cell. And performance estimation on the electron beam is being conducted. Presently, the devices for heat loading tests under steady state will be added to this facility.

  19. Micro-Shaping of Nanopatterned Surfaces by Electron Beam Irradiation

    Directory of Open Access Journals (Sweden)

    Carlos Angulo Barrios

    2016-04-01

    Full Text Available We show that planar nanopatterned thin films on standard polycarbonate (PC compact discs (CD can be micro-shaped in a non-contact manner via direct e-beam exposure. The shape of the film can be controlled by proper selection of the e-beam parameters. As an example of application, we demonstrate a two-dimensional (2D array of micro-lenses/reservoirs conformally covered by an Al 2D nanohole array (NHA film on a PC CD substrate. It is also shown that such a curvilinear Al NHA layer can be easily transferred onto a flexible polymeric support. The presented technique provides a new tool for creating lab-on-CD architectures and developing multifunctional (flexible non-planar nanostructured films and surfaces.

  20. Cryogenic Semiconductor Detectors: Simulation of Signal Formation & Irradiation Beam Test

    CERN Document Server

    AUTHOR|(CDS)2091318; Stamoulis, G; Vavougios, D

    The Beam Loss Monitoring system of the Large Hadron Collider is responsible for the pro- tection of the machine from damage and for the prevention of a magnet quench. Near the interaction points of the LHC, in the triplet magnets area, the BLMs are sensitive to the collision debris, limiting their ability to distinguish beam loss signal from signal caused due to the collision products. Placing silicon & diamond detectors inside the cold mass of the mag- nets, in liquid helium temperatures, would provide significant improvement to the precision of the measurement of the energy deposition in the superconducting coil of the magnet. To further study the signal formation and the shape of the transient current pulses of the aforementioned detectors in cryogenic temperatures, a simulation application has been developed. The application provides a fast way of determining the electric field components inside the detectors bulk and then introduces an initial charge distribution based on the properties of the radiat...

  1. Radiation-Induced Centers in Lead Silicate Glasses Irradiated by Stationary and Pulsed Electron Beams

    Science.gov (United States)

    Zhidkov, I. S.; Zatsepin, A. F.; Konev, S. F.; Cholakh, S. O.

    2015-08-01

    Radiation-induced centers formed in heavy flint glasses irradiated by electron beams are investigated by the methods of optical and EPR spectroscopy. It is revealed that stable and short-living optical absorption centers of close natures are formed under irradiation by fast electrons. A correlation is established between the stable optical absorption bands and the EPR signals interpreted as signals of the (Pb2+)/h+ hole centers. The shortliving color centers are formed due to short-term distortion of the O-Pb bonds, and the stable centers are formed due to the spatial separation, thermalization, and subsequent stabilization of excited electrons and holes in tails of the localized states. Irradiation by electron beams leads to a change in the spectral characteristics of the fundamental absorption edge and, in particular, of the Urbach energy that determines the degree of structural disorder.

  2. Modification of magnetic anisotropy in metallic glasses using high-energy ion beam irradiation

    Indian Academy of Sciences (India)

    K V Amrute; U R Mhatre; S K Sinha; D C Kothari; R Nagarajan; D Kanjilal

    2002-05-01

    Heavy ion irradiation in the electronic stopping power region induces macroscopic dimensional change in metallic glasses and introduces magnetic anisotropy in some magnetic materials. The present work is on the irradiation study of ferromagnetic metallic glasses, where both dimensional change and modification of magnetic anisotropy are expected. Magnetic anisotropy was measured using Mössbauer spectroscopy of virgin and irradiated Fe40Ni40B20 and Fe40Ni38Mo4B18 metallic glass ribbons. 90 MeV 127I beam was used for the irradiations. Irradiation doses were 5 × 1013 and 7.5 × 1013 ions/cm2. The relative intensity ratios 23 of the second and third lines of the Mössbauer spectra were measured to determine the magnetic anisotropy. The virgin samples of both the materials display in-plane magnetic anisotropy, i.e., the spins are oriented parallel to the ribbon plane. Irradiation is found to cause reduction in magnetic anisotropy. Near-complete randomization of magnetic moments is observed at high irradiation doses. Correlation is found between the residual stresses introduced by ion irradiation and the change in magnetic anisotropy.

  3. 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.

  4. Surface chemical changes of CaTiO3:Pr3+ upon electron beam irradiation

    International Nuclear Information System (INIS)

    Surface chemical changes of CaTiO3:Pr3+ phosphor material and their effect on the red emission intensity of the 1D2→3H4 transition of Pr3+, upon electron beam irradiation are presented. Red emission at 613 nm was obtained upon probing the surface with a 2 keV electron beam. The surface chemical changes and Pr3+ red emission were monitored using an Auger Electron Spectroscopy (AES) and Cathodoluminescence (CL) spectrometer, respectively. The CL intensity decreased with a decrease in O on the surface at 1×10−8 Torr base pressure and decreased with an increase in O on the surface at 1×10−6 Torr O2. The X-ray Photoelectron Spectroscopy (XPS) revealed that CL degradation at 1×10−6 Torr O2 is due to the formation of CaO and CaOx as well as TiO2/Ti2O3 non-luminescent species on the surface.

  5. Morphological change of self-organized protrusions of fluoropolymer surface by ion beam irradiation

    Science.gov (United States)

    Kitamura (Ogawa), Akane; Kobayashi, Tomohiro; Satoh, Takahiro; Koka, Masashi; Kamiya, Tomihiro; Suzuki, Akihiro; Terai, Takayuki

    2013-07-01

    Polytetrafluoroethylene (PTFE) and fluorinated ethylene propylene (FEP) are typical fluoropolymers displaying several desirable technological properties such as electrical insulation and high chemical resistance. When their surfaces are irradiated with ion beams, dense micro-protrusions formed after the emergence and spread of micropores across the entire irradiated area, allowing culture cells to spread on the top of the protrusions. In this study, we investigate the morphological changes introduced in the fluoropolymer surfaces by ion beams as the energy of the beams is increased. When an FEP sample was irradiated with a nitrogen ion beam with an energy of less than 350 keV at 1.0 μA/cm2, protrusions were formed with a density between 2 × 107/cm2 and 2 × 108/cm2. However, at energies higher than 350 keV, the protrusions became sparse, and the density dropped to 5 × 102/cm2. Protrusions appeared sporadically during irradiation at high energies, and the top of the protrusions appeared as spots inside the sample, which were difficult to etch and became elongated as the erosion of the surface progressed. Erosion was caused by sputtering of FEP molecules and evaporation at notably elevated temperatures on the surface. Analysis based on attenuated total reflectance/Fourier transform infrared spectroscopy showed the presence of Cdbnd C bonds as well as -COOH, -Cdbnd O, and -OH bonds on all irradiated samples. Their concentration on the surface densely covered with micro-protrusions was higher than that on the surface with sparse protrusions after irradiation at energies exceeding 350 keV. Thus, we determined a suitable range for the ion energy for creating FEP surfaces densely covered with protrusions.

  6. A study on the removal of color in dyeing wastewater using electron beam irradiation

    International Nuclear Information System (INIS)

    In this research, experiments of electron beam irradiation have been carried out for the wastewater from different types of dye industry, and for the reactive dye, for the acid dye and for the disperse dye which are commercially widely used with respect to industrial dyeing process. At the electron beam irradiation dose of 2.34KGy, the efficiency of color removing was higher than that of usual chemical treatment for the reactive dye and for the acid dye. Wastewater from printing dye industry showed the highest measuring value of color among the wastewater from different types of dye industries, which are polyester, cotton T/C, printing, yarn dyeing, and nylon dye industry. Electron beam irradiation tests have been performed for the wastewater from different types of dye industries. Color removing rates by electron beam irradiation were higher than those by general chemical treatment for the wastewater from cotton T/C dye industry and from yarn dyeing industry, and whose dispersive dye contents are low. EA (electron beam irradiation + activated sludge) process and CA (chemical treatment + activated sludge) process have been tested for removing color and organic substance in wastewater from different types of dye industries. EA process showed better results in color removing rate for the wastewater from cotton T/C dye industry and yarn dyeing industry. However, CA process showed better results in color removing rate for the wastewater from polyester, printing, and nylon dye industry. CA process were predominant in CODMn removal rates compare to EA process for the wastewater from different types of dye industries. However, both CA and EA processes showed less than 80mg/L of BOD5, which is the legal effluent guideline. (author)

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

    International Nuclear Information System (INIS)

    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. Electron beam irradiation and zeolites adsorption applied to dyeing effluents

    Energy Technology Data Exchange (ETDEWEB)

    Higa, Marcela C.; Fungaro, Denise A.; Somessari, Elizabeth S.R.; Magdalena, Carina P.; Grosche, Lucas C.; NNeto, Antonio C.; Borrely, Sueli I. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2007-07-01

    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)

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

    International Nuclear Information System (INIS)

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

  10. Evaluation of TL response and intrinsic efficiency of TL dosimeters irradiated using different phantoms in clinical electron beam dosimetry

    International Nuclear Information System (INIS)

    The TL response of LiF:Mg,Ti microdosimeters and CaSO4:Dy dosimeters were studied for 12 MeV electron beams using PMMA, liquid water and solid water (SW) phantoms. The different phantom materials affect the electron spectrum incident on the detector and it can alter the response of dosimeters to different radiation types, so this fact should be considered in clinical dosimetry. The dosimeters were irradiated with doses ranging from 0.1 up to 5 Gy using a Varian Clinac 2100C linear accelerator of Hospital Israelita Albert Einstein – HIAE using a 10 × 10 cm2 field size and 100 cm source-phantom surface distance, with the dosimeters positioned at the depth of maximum dose. The TL readings were carried out 24 h after irradiation using a Harshaw 3500 TL reader. This paper aims to compare the TL response relative to 60Co of the dosimeters for different phantoms used in radiotherapy dosimetry. CaSO4:Dy dosimeters presented higher TL sensitivity relative to 60Co and intrinsic efficiency than microLiF:Mg,Ti dosimeters for all phantoms. - Highlights: • TL dose response curves of the dosimeters for clinical electron beams. • Evaluation of dosimeters for different phantoms. • Sensitivity and intrinsic TL efficiency of the dosimeters for clinical electron beams. • Effect of phantom materials in clinical electron beam dosimetry

  11. Storage Stability in Reversion Mutation of a Rice Line Devoid of LOX-1, 2 Acquired by Ion Beam Irradiation

    International Nuclear Information System (INIS)

    The effect of absence of lipoxygenase isoenzyme (LOX) on storage stability was investigated. Rice mutant 1297 without lipoxygenase isoenzyme-1 LOX-1 or lipoxygenase isoenzyme-2 (LOX-2) generated by ion beam irradiation from Wanjian2090 and reversion mutant RM1297 with LOX-1 and LOX-2 were subjected to an accelerated-aging experiment. Shanyou63 (with LOX-1 and LOX-2) served as control. Results showed that the germination and dehydrogenase activity decreased while the electrical conductivity and free fatty acid content increased in all varieties with accelerated aging. In 1297 that lacked LOX-1 and 2, there were slight changes in germination, dehydrogenase activity, membrane permeability and free fatty acid content during the thirty-day accelerated-aging experiment. But in varieties with LOX-1 and LOX-2, significant changes were observed, suggesting that LOX-1, 2 might be a definite factor which influenced seed lifespan. This study also indicates that ion beam irradiation may be used as mutagen to generate mutant and reversion mutants for biological study and could become a new direction in ion beam application. (ion beam bioengineering)

  12. Improving enzymatic hydrolysis of industrial hemp (Cannabis sativa L.) by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Soo-Jeong [Chungbuk National University, Cheongju, Chungbuk 361-763 (Korea, Republic of); Sung, Yong Joo [KT and G Central Research Institute, 302 Shinseong-Dong, Yuseong-Gu, Daejeon 305-805 (Korea, Republic of)], E-mail: yosung17@yahoo.co.kr

    2008-09-15

    The electron beam irradiation was applied as a pretreatment of the enzymatic hydrolysis of hemp biomass with doses of 150, 300 and 450 kGy. The higher irradiation dose resulted in the more extraction with hot-water extraction or 1% sodium hydroxide solution extraction. The higher solubility of the treated sample was originated from the chains scission during irradiation, which was indirectly demonstrated by the increase of carbonyl groups as shown in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) spectra. The changes in the micro-structure of hemp resulted in the better response to enzymatic hydrolysis with commercial cellulases (Celluclast 1.5L and Novozym 342). The improvement in enzymatic hydrolysis by the irradiation was more evident in the hydrolysis of the xylan than in that of the cellulose.

  13. Tuning the transport gap of functionalized graphene via electron beam irradiation

    International Nuclear Information System (INIS)

    We demonstrate a novel method to tune the energy gap ϵ1 between the localized states and the mobility edge of the valence band in chemically functionalized graphene by changing the coverage of fluorine adatoms via electron-beam irradiation. From the temperature dependence of the electrical transport properties we show that ϵ1 in partially fluorinated graphene CF0.28 decreases upon electron irradiation up to a dose of 0.08 C cm−2. For low irradiation doses (−2) partially fluorinated graphene behaves as a lightly doped semiconductor with impurity bands close to the conduction and valence band edges, whereas for high irradiation doses (>0.2 C cm−2) the electrical conduction takes place via Mott variable range hopping. (paper)

  14. Transplantation of ES cells to Parkinson model rat irradiated with carbon ion beam

    International Nuclear Information System (INIS)

    The present study was designed to make a new Parkinson disease model using carbon ion beam. We irradiated right medial forebrain bundle of adult SD rats with charged carbon particles (290 MeV/nucleon, Mono peak, 150 Gy) and damaged right dopaminergic neurons pathway. To irradiate precisely, rats were set in the stereotactic frame with ear bars. Four weeks after the irradiation, behavioral test and in vitro autoradiography showed hemi-Parkinson model as well as 6-OHDA lesioned rats. Pathological examinations showed cell death, gliosis and inflammations at the irradiated area. However, no obvious alteration was observed at the surrounding normal tissue. These results indicated utility and validity of this method. (author)

  15. Improving enzymatic hydrolysis of industrial hemp (Cannabis sativa L.) by electron beam irradiation

    International Nuclear Information System (INIS)

    The electron beam irradiation was applied as a pretreatment of the enzymatic hydrolysis of hemp biomass with doses of 150, 300 and 450 kGy. The higher irradiation dose resulted in the more extraction with hot-water extraction or 1% sodium hydroxide solution extraction. The higher solubility of the treated sample was originated from the chains scission during irradiation, which was indirectly demonstrated by the increase of carbonyl groups as shown in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) spectra. The changes in the micro-structure of hemp resulted in the better response to enzymatic hydrolysis with commercial cellulases (Celluclast 1.5L and Novozym 342). The improvement in enzymatic hydrolysis by the irradiation was more evident in the hydrolysis of the xylan than in that of the cellulose

  16. Fast crystallization of amorphous Gd{sub 2}Zr{sub 2}O{sub 7} induced by thermally activated electron-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Zhangyi; Qi, Jianqi, E-mail: qijianqi@scu.edu.cn; Zhou, Li; Feng, Zhao; Yu, Xiaohe [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Gong, Yichao [College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China); Yang, Mao; Wei, Nian [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Key Laboratory of High Energy Density Physics of Ministry of Education, Sichuan University, Chengdu 610064 (China); Shi, Qiwu [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China); Lu, Tiecheng, E-mail: lutiecheng@scu.edu.cn [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Key Laboratory of High Energy Density Physics of Ministry of Education, Sichuan University, Chengdu 610064 (China)

    2015-12-07

    We investigate the ionization and displacement effects of an electron-beam (e-beam) on amorphous Gd{sub 2}Zr{sub 2}O{sub 7} synthesized by the co-precipitation and calcination methods. The as-received amorphous specimens were irradiated under electron beams at different energies (80 keV, 120 keV, and 2 MeV) and then characterized by X-ray diffraction and transmission electron microscopy. A metastable fluorite phase was observed in nanocrystalline Gd{sub 2}Zr{sub 2}O{sub 7} and is proposed to arise from the relatively lower surface and interface energy compared with the pyrochlore phase. Fast crystallization could be induced by 120 keV e-beam irradiation (beam current = 0.47 mA/cm{sup 2}). The crystallization occurred on the nanoscale upon ionization irradiation at 400 °C after a dose of less than 10{sup 17} electrons/cm{sup 2}. Under e-beam irradiation, the activation energy for the grain growth process was approximately 10 kJ/mol, but the activation energy was 135 kJ/mol by calcination in a furnace. The thermally activated ionization process was considered the fast crystallization mechanism.

  17. Calibrated photostimulated luminescence is an effective approach to identify irradiated orange during storage

    International Nuclear Information System (INIS)

    Photostimulated luminescence (PSL) has been employed as a fast screening method for various irradiated foods. In this study the potential use of PSL was evaluated to identify oranges irradiated with gamma ray, electron beam and X-ray (0–2 kGy) and stored under different conditions for 6 weeks. The effects of light conditions (natural light, artificial light, and dark) and storage temperatures (4 and 20 °C) on PSL photon counts (PCs) during post-irradiation periods were studied. Non-irradiated samples always showed negative values of PCs, while irradiated oranges exhibited intermediate results after first PSL measurements. However, the irradiated samples had much higher PCs. The PCs of all the samples declined as the storage time increased. Calibrated second PSL measurements showed PSL ratio <10 for the irradiated samples after 3 weeks of irradiation confirming their irradiation status in all the storage conditions. Calibrated PSL and sample storage in dark at 4 °C were found out to be most suitable approaches to identify irradiated oranges during storage. - Highlights: • Photostimulatedluminescence (PSL) was studied to identify irradiated orange for quarantine application. • PSL detection efficiency was compared amonggamma,electron, and X irradiation during shelf-life of oranges • PSL properties of samples were characterized by standard samples • Calibrated PSL gave a clear verdict on irradiation extending potential of PSL technique

  18. Developing of the protocol for electron beam food irradiation facility

    International Nuclear Information System (INIS)

    By establishing the needs for institution of new technologies in the process of food processing, in this case a randomized choice of electron beam accelerator facility, arises the need for designing a protocol for safe and secure performance of the facility. The protocol encompasses safety and security measures for protection from ionizing radiation of the individuals who work at the facility, as well as, the population and the environment in the immediate neighborhood of the facility. Thus, the adopted approach is the establishment of appropriate systems responding to the protocol. Dosimetry system, which includes appropriate procedures for accurate measure and recording of the absorbed dose values, according to the provisions for protection from ionizing radiation. Ionizing radiation protection system and providing the safety and security of the facility for food processing by means of ionizing radiation. System for providing quality and safety control of the facility for food processing by means of ionizing radiation. Pursuant to the designed a protocol for safe and secure performance of the facility for electron beam food processing, contributes to protection against ionizing radiation as occupationally exposed persons as well the population. (Author)

  19. The influence of electron beam irradiation on the mechanical and thermal properties of Poly (ether-block-amide) blends

    International Nuclear Information System (INIS)

    High energy electron beam irradiation of Poly (ether-block-amide) (Pebax) can induce modifications and/or degradation to transpire in the material subsequent to treatment. To minimise this, Pebax was blended with three stabilisers where each formulation was subjected to electron beam radiation at doses of 25, 50 and 75 kGy. Mechanical testing revealed that the virgin Pebax and the Pebax blended with Irganox B215 provided the best radiation resistance in terms of the tensile strength, elongation at break and Young's modulus. Upon increase in radiation dose from 25 to 75 kGy, a gradual diminution was observed for the melt flow index (MFI) of the virgin Pebax, whereas Pebax blended with Irganox B215 had a minute effect on the properties post irradiation. This study provides evidence that the stabilisers used can either promote undesirable effects or enhance the radiation resistance of Pebax material following radiation exposure. Highlights: • Mechanical properties of Pebax and Irganox 565 can be controlled by radiation dose • Virgin Pebax and Pebax blended with Irgnaox B215 provides good radiation resistance • MFI decreases gradually for the Virgin Pebax with an increase in radiation dose • Molecular weight of Pebax and Irganox B215 is less effected by radiation dose • Simultaneous chain scission and crosslinking/branching occurs during irradiation

  20. Cross-sectional TEM Observations of Si Wafers Irradiated With Gas Cluster Ion Beams

    International Nuclear Information System (INIS)

    Irradiation by a Gas Cluster Ion Beam (GCIB) is a promising technique for precise surface etching and planarization of Si wafers. However, it is very important to understand the crystalline structure of Si wafers after GCIB irradiation. In this study, the near surface structure of a Si (100) wafer was analyzed after GCIB irradiation, using a cross-sectional transmission electron microscope (XTEM). Ar-GCIB, that physically sputters Si atoms, and SF6-GCIB, that chemically etches the Si surface, were both used. After GCIB irradiation, high temperature annealing was performed in a hydrogen atmosphere. From XTEM observations, the surface of a virgin Si wafer exhibited completely crystalline structures, but the existence of an amorphous Si and a transition layer was confirmed after GCIB irradiation. The thickness of amorphous layer was about 30 nm after Ar-GCIB irradiation at 30 keV. However, a very thin (< 5 nm) layer was observed when 30 keV SF6-GCIB was used. The thickness of the transition layer was the same both Ar and SF6-GCIB irradiation. After annealing, the amorphous Si and transition layers had disappeared, and a complete crystalline structure with an atomically smooth surface was observed

  1. Direct patterning of gold oxide thin films by focused ion-beam irradiation

    Science.gov (United States)

    Machalett, F.; Edinger, K.; Melngailis, J.; Diegel, M.; Steenbeck, K.; Steinbeiss, E.

    For direct writing of electrically conducting connections and areas into insulating gold oxide thin films a scanning Ar+ laser beam and a 30 keV Ga+ focused ion beam (FIB) have been used. The gold oxide films are prepared by magnetron sputtering under argon/oxygen plasma. The patterning of larger areas (dimension 10-100 μm) has been carried out with the laser beam by local heating of the selected area above the decomposition temperature of AuOx (130-150 °C). For smaller dimensions (100 nm to 10 μm) the FIB irradiation could be used. With both complementary methods a reduction of the sheet resistance by 6-7 orders of magnitude has been achieved in the irradiated regions (e.g. with FIB irradiation from 1.5×107 Ω/□ to approximately 6 Ω/□). The energy-dispersive X-ray analysis (EDX) show a considerably reduced oxygen content in the irradiated areas, and scanning electron microscopy (SEM), as well as atomic force microscopy (AFM) investigations, indicate that the FIB patterning in the low-dose region (1014 Ga+/cm2) is combined with a volume reduction, which is caused by oxygen escape rather than by sputtering.

  2. Influence of electron beam Irradiation on PP/Piassava fiber composite prepared by melt extrusion process

    International Nuclear Information System (INIS)

    In the latest years, the interest for the use of natural fibers in materials composites polymeric has increased significantly due to their environmental and technological advantages. Piassava fibers (Attalea funifera) have been used as reinforcement in the matrix of thermoplastic and thermoset polymers. In the present work (20%, in mass), piassava fibers with particle sizes equal or smaller than 250 μm were incorporated in the polypropylene matrix (PP) no irradiated and polypropylene matrix containing 10 % and 30 % of polypropylene treated by electron-beam radiation at 40 kGy (PP/PPi/Piassava). The composites PP/Piassava and PP/PPi/Piassava were prepared by using a twin screw extruder, followed by injection molding. The composite material samples obtained were treated by electron-beam radiation at 40 kGy, using a 1.5 MeV electron beam accelerator, at room temperature, in presence of air. After irradiation treatment, the irradiated and non-irradiated specimens tests samples were submitted to thermo-mechanical tests, melt flow index (MFI), sol-gel analysis, X-Ray diffraction (XRD) and scanning electron microscopy (SEM). (author)

  3. Development of abiotic-stress resistant warm season trufgrasses by proton-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Y. W.; Kim, J. Y.; Jeong, S. H. [Korea Univ., Seoul (Korea, Republic of)

    2007-04-15

    The direct use of mutation is a valuable approach to generate genetic variation in crop species by altering agronomically useful major traits. The proton beam, as a mutagen, was applied to improve resistance traits of Zoysia grass under various abiotic stresses. Proton beam was irradiated to mature dry seeds of Zenith (Zoysia grass), which is well-adapted to Korean climate, using a proton- accelerator with seven different doses (50, 100, 150, 200, 250, 300, 400 Gy). Individual seedling of M1 plant was transplanted from the seed bed and allowed to reach appropriate plant mass. Clones that showed superior growth were chosen and transplanted to pots for further clone propagation and field evaluation. Growth characteristics of turfgrass, such as plant height, leaf length, leaf width, number of tiller were evaluated ninety days after sowing. Although large variation within each dose, noticeable differences were found among different irradiated doses. Most of the mutant clones derived from the irradiation treatment showed more vigorous growth than the control plants. RAPD (Random Amplified Polymorphic DNA) and AFLP (Amplified Fragment Length Polymorphism) methods were conducted to analyze genomic variations associated with proton beam irradiation. In order to establish selection criteria for selection of salt-stress resistance plants, an in vitro method that is able to select salt-stress resistant mutants in liquid media without ambient disturbances. Total 647 predominance clones that were considered as abiotic stress resistant mutants were transplanted to the field for further evaluation.

  4. Biological effects of 12C6+ heavy ions irradiation on Allium fistulosum L

    International Nuclear Information System (INIS)

    In order to study biological effects of 12C6+ heavy ions irradiation on Allium fistulosum L., the dry seeds were treated by 12C6+ heavy ion beam with different doses. Obvious 'parabola' trends were observed in the characteristics of germination rate and height of Allium fistulosum L. seedling when irradiated doses increased. With irradiation of an appropriate dose of 12C6+ heavy ion beam, 30Gy, the germination rate of Allium fistulosum L. is increased and the seedlings can resist drought and lodging, and grow better than the control. At the same time, the formation frequency of micronucleus and chromosomal aberration were surveyed in root-tip cells. The highest formation frequency of micronucleus and chromosomal aberration treated with 180Gy could reach to 9.09% and 10.03% respectively. This study laid the basis for further work on breeding and improvement of Allium fistulosum L. irradiated by 12C6+ heavy ion beam. (authors)

  5. Irradiation effects in YBCO thin films

    International Nuclear Information System (INIS)

    Oxide superconductors are very sensitive to electron or ion beam irradiation/implantation. In the past 19 years after high-Tc (HTc) superconductivity was discovered in these materials, many aspects of interactions of accelerated particles with HTc thin films were investigated. In this paper short review of most significant phenomena is given, especially of those important for electronic applications (controllable reduction of critical temperature and critical current density) and their applications for HTc film patterning, fabrication of HTc Josephson junctions and SQUIDs. Some new results in creating 3-d inhomogeneous regions in YBCO superconductors by ion irradiation/implantation and investigation of high harmonic generation in YBCO film modified by 100 keV oxygen ions are presented. (author)

  6. A novel algorithm for the calculation of physical and biological irradiation quantities in scanned ion beam therapy: the beamlet superposition approach

    Science.gov (United States)

    Russo, G.; Attili, A.; Battistoni, G.; Bertrand, D.; Bourhaleb, F.; Cappucci, F.; Ciocca, M.; Mairani, A.; Milian, F. M.; Molinelli, S.; Morone, M. C.; Muraro, S.; Orts, T.; Patera, V.; Sala, P.; Schmitt, E.; Vivaldo, G.; Marchetto, F.

    2016-01-01

    The calculation algorithm of a modern treatment planning system for ion-beam radiotherapy should ideally be able to deal with different ion species (e.g. protons and carbon ions), to provide relative biological effectiveness (RBE) evaluations and to describe different beam lines. In this work we propose a new approach for ion irradiation outcomes computations, the beamlet superposition (BS) model, which satisfies these requirements. This model applies and extends the concepts of previous fluence-weighted pencil-beam algorithms to quantities of radiobiological interest other than dose, i.e. RBE- and LET-related quantities. It describes an ion beam through a beam-line specific, weighted superposition of universal beamlets. The universal physical and radiobiological irradiation effect of the beamlets on a representative set of water-like tissues is evaluated once, coupling the per-track information derived from FLUKA Monte Carlo simulations with the radiobiological effectiveness provided by the microdosimetric kinetic model and the local effect model. Thanks to an extension of the superposition concept, the beamlet irradiation action superposition is applicable for the evaluation of dose, RBE and LET distributions. The weight function for the beamlets superposition is derived from the beam phase space density at the patient entrance. A general beam model commissioning procedure is proposed, which has successfully been tested on the CNAO beam line. The BS model provides the evaluation of different irradiation quantities for different ions, the adaptability permitted by weight functions and the evaluation speed of analitical approaches. Benchmarking plans in simple geometries and clinical plans are shown to demonstrate the model capabilities.

  7. Microstructural evolution in austenitic stainless steel irradiated with triple-beam

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, Shozo; Miwa, Yukio; Yamaki, Daiju [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Zhang Yichuan

    1997-03-01

    An austenitic stainless steel was simultaneously irradiated with nickel, helium and hydrogen ions at the temperature range of 573-673 K. The damage level and injected concentration of He and H ions in the triple-beam irradiated region are 57 dpa, 19000 and 18000 at.ppm, respectively. Following to irradiation, the cross sectional observation normal to the incident surface of the specimen was carried out with a transmission electron microscope. Two bands parallel to the incident surface were observed in the irradiated specimen, which consist of dislocation loops and lines of high number density. These locate in the range of the depth of 0.4 to 1.3 {mu}m and 1.8 to 2.4 {mu}m from the incident surface, respectively. The region between two bands, which corresponds to the triple beam irradiated region, shows very low number density of dislocations than that in each band. Observation with higher magnification of this region shows that fine cavities with high number density uniformly distribute in the matrix. (author)

  8. Oxygen-Content-Controllable Graphene Oxide from Electron-Beam-Irradiated Graphite: Synthesis, Characterization, and Removal of Aqueous Lead [Pb(II)].

    Science.gov (United States)

    Bai, Jing; Sun, Huimin; Yin, Xiaojie; Yin, Xianqiang; Wang, Shengsen; Creamer, Anne Elise; Xu, Lijun; Qin, Zhi; He, Feng; Gao, Bin

    2016-09-28

    A high-energy electron beam was applied to irradiate graphite for the preparation of graphene oxide (GO) with a controllable oxygen content. The obtained GO sheets were analyzed with various characterization tools. The results revealed that the oxygen-containing groups of GO increased with increasing irradiation dosages. Hence, oxygen-content-controllable synthesis of GO can be realized by changing the irradiation dosages. The GO sheets with different irradiation dosages were then used to adsorb aqueous Pb(II). The effects of contact time, pH, initial lead ion concentration, and ionic strength on Pb(II) sorption onto different GO sheets were examined. The sorption process was found to be very fast (completed within 20 min) at pH 5.0. Except ionic strength, which showed no/little effect on lead sorption, the other factors affected the sorption of aqueous Pb(II) onto GO. The maximum Pb(II) sorption capacities of GO increased with irradiation dosages, confirming that electron-beam irradiation was an effective way to increase the oxygen content of GO. These results suggested that irradiated GO with a controllable oxygen content is a promising nanomaterial for environmental cleanup, particularly for the treatment of cationic metal ions, such as Pb(II).

  9. Virus inactivation studies using ion beams, electron and gamma irradiation

    International Nuclear Information System (INIS)

    Known methods of virus inactivation are based on the chemical action of some substances such as acetylethylenimine, betapropiolactone, glycidalaldehyde, formaldehyde, etc. In such a process, the viral suspension should be kept at room or higher temperatures for 24-48 h. Under these conditions, physical and chemical agents act to degrade the virus antigenic proteins. On the contrary with ionizing radiations at low temperatures, the treatment does not cause such degradation allowing the study of different viral functions. In this work, particle (α, d and ss) and γ irradiations were used for partial and total inactivation of Foot and Mouth Disease Virus (FMDV), Rauscher Leukemia Virus (RLV) and Herpes Simplex Virus (HSV). Obtention of the D37 dose from survival curves and the application of the target theory, permitted the determination of molecular weight of the nucleic acid genomes, EBR values and useful information for vaccine preparation. For RLV virus, a two target model of the RNA genome was deduced in accordance with biological information while from data from the literature and our own work on the structure of the scrapie prion, considering the molecular weight obtained by application of the theory, a new model for prion replication is presented, based on a trimer molecule

  10. Virus inactivation studies using ion beams, electron and gamma irradiation

    Science.gov (United States)

    Smolko, Eduardo E.; Lombardo, Jorge H.

    2005-07-01

    Known methods of virus inactivation are based on the chemical action of some substances such as acetylethylenimine, betapropiolactone, glycidalaldehyde, formaldehyde, etc. In such a process, the viral suspension should be kept at room or higher temperatures for 24-48 h. Under these conditions, physical and chemical agents act to degrade the virus antigenic proteins. On the contrary with ionizing radiations at low temperatures, the treatment does not cause such degradation allowing the study of different viral functions. In this work, particle (α, d and ß) and γ irradiations were used for partial and total inactivation of Foot and Mouth Disease Virus (FMDV), Rauscher Leukemia Virus (RLV) and Herpes Simplex Virus (HSV). Obtention of the D37 dose from survival curves and the application of the target theory, permitted the determination of molecular weight of the nucleic acid genomes, EBR values and useful information for vaccine preparation. For RLV virus, a two target model of the RNA genome was deduced in accordance with biological information while from data from the literature and our own work on the structure of the scrapie prion, considering the molecular weight obtained by application of the theory, a new model for prion replication is presented, based on a trimer molecule.

  11. Virus inactivation studies using ion beams, electron and gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Smolko, Eduardo E. [Laboratorio de Polimeros, Grupo Aplicaciones Industriales, Unidad de Aplicaciones Tecnologicas y Agropecuarias, Centro Atomico Ezeiza, Comision Nacional de Energia Atomica, Pbro. Juan Gonzalez y Aragon 15, C.P. B1802AYA Ezeiza, Buenos Aires (Argentina)]. E-mail: smolko@cae.cnea.gov.ar; Lombardo, Jorge H. [Biotech S.A., C.P. 1754 Buenos Aires (Argentina)

    2005-07-01

    Known methods of virus inactivation are based on the chemical action of some substances such as acetylethylenimine, betapropiolactone, glycidalaldehyde, formaldehyde, etc. In such a process, the viral suspension should be kept at room or higher temperatures for 24-48 h. Under these conditions, physical and chemical agents act to degrade the virus antigenic proteins. On the contrary with ionizing radiations at low temperatures, the treatment does not cause such degradation allowing the study of different viral functions. In this work, particle ({alpha}, d and ss) and {gamma} irradiations were used for partial and total inactivation of Foot and Mouth Disease Virus (FMDV), Rauscher Leukemia Virus (RLV) and Herpes Simplex Virus (HSV). Obtention of the D{sub 37} dose from survival curves and the application of the target theory, permitted the determination of molecular weight of the nucleic acid genomes, EBR values and useful information for vaccine preparation. For RLV virus, a two target model of the RNA genome was deduced in accordance with biological information while from data from the literature and our own work on the structure of the scrapie prion, considering the molecular weight obtained by application of the theory, a new model for prion replication is presented, based on a trimer molecule.

  12. Studies on electron-beam irradiation and plastic deformation of medical-grade ultra-high molecular weight polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Czaja, Krystyna, E-mail: krystyna.czaja@uni.opole.p [Opole University, Faculty of Chemistry, Oleska 48, 45-052 Opole (Poland); SudoL, Marek [Opole University, Faculty of Chemistry, Oleska 48, 45-052 Opole (Poland)

    2011-03-15

    Separated and combined electron-beam irradiation and plastic deformation effects on the structures of ultra-high molecular weight polyethylene (UHMWPE) were studied. It was found that the concentration of carbonyl (ketones, esters and peresters), hydroxyl and vinyl groups increases with the growing dose of adsorbed electrons. It also tends to exhibit a slight increase in the melting point and crystallinity of the samples. A mechanical stress in the polymer was found to accelerate radiation-induced degradation. It was concluded that each of the factors studied (i.e. electron beam sterilization and plastic deformation) had a different impact on the polymer structure. The change in the sequence of action of these factors can dramatically influence the process of UHMWPE destruction. Some effects may be limited or enhanced by the action of other factors. Therefore, the resulting effects of destructive factors depend qualitatively and quantitatively on their intensity and order.

  13. Studies on electron-beam irradiation and plastic deformation of medical-grade ultra-high molecular weight polyethylene

    Science.gov (United States)

    Czaja, Krystyna; SudoŁ, Marek

    2011-03-01

    Separated and combined electron-beam irradiation and plastic deformation effects on the structures of ultra-high molecular weight polyethylene (UHMWPE) were studied. It was found that the concentration of carbonyl (ketones, esters and peresters), hydroxyl and vinyl groups increases with the growing dose of adsorbed electrons. It also tends to exhibit a slight increase in the melting point and crystallinity of the samples. A mechanical stress in the polymer was found to accelerate radiation-induced degradation. It was concluded that each of the factors studied (i.e. electron beam sterilization and plastic deformation) had a different impact on the polymer structure. The change in the sequence of action of these factors can dramatically influence the process of UHMWPE destruction. Some effects may be limited or enhanced by the action of other factors. Therefore, the resulting effects of destructive factors depend qualitatively and quantitatively on their intensity and order.

  14. Vacancy type defect formation in irradiated α-iron investigated by positron beam Doppler broadening technique

    International Nuclear Information System (INIS)

    Vacancy type defects formations have been investigated in virgin and irradiated a-iron samples using slow positron beam Doppler broadening technique. Mono-vacancies and vacancy clusters are observed in 1.5 MeV 4He ions irradiated Fe samples at varying fluences from 1×1013 to 1×1017 cm−2. In the 1.2 MeV Yttrium ions implantation at low fluence 1×1014 cm−2 vacancy clusters with higher concentration and larger size are formed. In this sample, vacancy defects are detected deeper than predicted by SRIM calculation due to channelling.

  15. Biological Effects on Fruit Fly by N+ ion Beam Implantation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Mutation induced by low energy ion beam implantation has beenapplied widely both in plants and microbes. However, due to the vacuum limitation, such ion implantation into animals was never studied except for silkworm. In this study, Pupae of fruit fly were irradiated with different dosage N+ ions at energy 20 KeV to study the biological effect of ion beam on animal. The results showed a saddle-like curve exists between incubate rate and dosage. Damage of pupae by ion beam implantation was observed using scanning electron microscope. Some individuals with incomplete wing were obtained after implantation but no similar character was observed in their offspring. Furthermore, about 5.47% mutants with wide variation appeared in M1 generation. Therefore, ion beam implantation could be widely used for mutation breeding.

  16. General design of the International Fusion Materials Irradiation Facility deuteron injector: Source and beam line

    International Nuclear Information System (INIS)

    In the framework of the International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities (IFMIF-EVEDA) project, CEA/IRFU is in charge of the design and realization of the 140 mA cw deuteron Injector. The electron cyclotron resonance ion source operates at 2.45 GHz and a 4 electrode extraction system has been chosen. A 2 solenoid beam line, together with a high space charge compensation have been optimized for a proper beam injection in the 175 MHz radio frequency quadrupole. The injector will be tested with proton and deuteron beam production either in pulsed mode or in cw mode on the CEA-Saclay site before to be shipped to Japan. Special attention was paid to neutron emission due to (d,D) reaction. In this paper, the general IFMIF Injector design is reported, pointing out beam dynamics, radioprotection, diagnostics, and mechanical aspects.

  17. Directed fast electron beams in ultraintense picosecond laser irradiated solid targets

    International Nuclear Information System (INIS)

    We report on fast electron transport and emission patterns from solid targets irradiated by s-polarized, relativistically intense, picosecond laser pulses. A beam of multi-MeV electrons is found to be transported along the target surface in the laser polarization direction. The spatial-intensity and energy distributions of this beam are compared with the beam produced along the laser propagation axis. It is shown that even for peak laser intensities an order of magnitude higher than the relativistic threshold, laser polarization still plays an important role in electron energy transport. Results from 3D particle-in-cell simulations confirm the findings. The characterization of directional beam emission is important for applications requiring efficient energy transfer, including secondary photon and ion source development

  18. Outline of irradiation service equipment and properties of its electron beam

    International Nuclear Information System (INIS)

    Current ethylene oxide sterilization becomes a subject of discussion on the safety for workers' health. On the other hand, demands for sterilization of disposable health care products and food packaging materials are increasing. On this situation, it is progressing to switch to radiation sterilization witch is easy to adapt to requirements of ISO validation, in particular to electron beam sterilization using electron accelerator, which is safer and easier to control. Our company started electron beam treatment service such as pasteurization, disinfestation, and improvement of polymers as well as sterilization, with introducing a high energy and high power electron accelerator. In this paper, basics of e-beam sterilization, outline of the irradiation service plant and the electron accelerator, and the properties of its electron beam are described. (author)

  19. Physical and biological properties of the ion beam irradiated PMMA-based composite films

    Energy Technology Data Exchange (ETDEWEB)

    Shanthini, G.M.; Martin, Catherine Ann; Sakthivel, N.; Veerla, Sarath Chandra; Elayaraja, K. [Crystal Growth Centre, Anna University, Chennai 600025 (India); Lakshmi, B.S. [Department of Biotechnology, Anna University, Chennai 600025 (India); Asokan, K.; Kanjilal, D. [Materials Science Group, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Kalkura, S. Narayana, E-mail: kalkurasn@annauniv.edu [Crystal Growth Centre, Anna University, Chennai 600025 (India)

    2015-02-28

    Highlights: • First report of swift heavy ion irradiation on PMMA-HAp as bioceramic composite. • Augmented protein adsorption of about 400% was attained due to irradiation. • Tailored surface morphology, topography, roughness, wettability and crystallinity. • Irradiation transformed the hydrophobic surface into hydrophilic surface. • Better blood and cell–material interaction leading to improved biocompatibility. - Abstract: Polymethyl methacrylate (PMMA) and PMMA-hydroxyapatite (PMMA-HAp) composite films, prepared by the solvent evaporation method were irradiated with 100 MeV Si{sup 7+} ions. Crystallographic, morphological and the functional groups of the pristine and irradiated samples were studied using glancing incident X-ray diffraction (GIXRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) respectively. SEM reveals the creation of pores, along with an increase in porosity and cluster size on irradiation. Decrease in crystalline nature and crystallite size with an increase in ion fluence was observed from GIXRD patterns. The surface roughness and the wettability of the material were also enhanced, which could favour the cell–material interaction. The irradiated samples adsorbed significantly greater amount of proteins than pristine. Also, irradiation does not produce any toxic byproducts or leachants, and maintains the viability of 3T3 cells. The response of the irradiated samples towards biomedical applications was demonstrated by the improved antimicrobial activity, haemocompatibility and cytocompatibility. Swift heavy ion irradiation (SHI) could be an effective tool to modify and engineer the surface properties of the polymers to enhance the biocompatibility.

  20. Investigation of effect of electron beam on various polyethylene blends

    CERN Document Server

    Morshedian, J

    2003-01-01

    With regards to the expanding usage of electron beams irradiation in polymer industries such as sterilization of polymeric disposable medical products; cable manufacturing; pipes, heat shrinkable materials, etc. In this project the effect of electron beam on polyethylene used in manufacturing of pipe and heat shrinkable products was studied. Results showed that by increasing the applied dose on samples; the crosslink density would increase and polymers with tertiary carbon atoms in their backbone structure tend to crosslink more readily. The melting temperature and crystallinity percent decreased and degradation temperature increased. Density in low doses decreased and in high doses increased.

  1. Comparison of gamma ray and electron beam irradiation on extraction yield, morphological and antioxidant properties of polysaccharides from tamarind seed

    Science.gov (United States)

    Choi, Jong-il; Kim, Jae-Kyung; Srinivasan, Periasamy; Kim, Jae-Hun; Park, Hyun-Jin; Byun, Myung-Woo; Lee, Ju-Woon

    2009-07-01

    Tamarind ( Tamarindus indica L) seed polysaccharide (TSP) is of great important due to its various biological activities. The present investigation was carried out to compare extraction yield, morphological characteristics, average molecular weights and antioxidant activities of TSP from gamma- and electron beam (EB)-irradiated tamarind kernel powder. The tamarind kernel powder was irradiated with 0, 5 and 10 kGy by gamma ray (GR) and electron beam, respectively. The extraction yield of TSP was increased significantly by EB and GR irradiation, but there was no significant difference between irradiation types. Morphological studies by scanning electron microscope showed that TSP from GR-irradiated tamarind seed had a fibrous structure, different from that of EB irradiated with a particle structures. The average molecular weight of TSP was decreased by the irradiation, and EB treatment degraded more severely than GR. Superoxide radical scavenging ability and total antioxidant capacity of EB-treated TSP showed higher than those of GR-treated TSP.

  2. Comparison of gamma ray and electron beam irradiation on extraction yield, morphological and antioxidant properties of polysaccharides from tamarind seed

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong-il [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kim, Jae-Kyung [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Graduate school of Food and Biotechnology, Korea University, Seoul 146-701 (Korea, Republic of); Srinivasan, Periasamy; Kim, Jae-Hun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Park, Hyun-Jin [Graduate school of Food and Biotechnology, Korea University, Seoul 146-701 (Korea, Republic of); Byun, Myung-Woo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

    2009-07-15

    Tamarind (Tamarindus indica L) seed polysaccharide (TSP) is of great important due to its various biological activities. The present investigation was carried out to compare extraction yield, morphological characteristics, average molecular weights and antioxidant activities of TSP from gamma- and electron beam (EB)-irradiated tamarind kernel powder. The tamarind kernel powder was irradiated with 0, 5 and 10 kGy by gamma ray (GR) and electron beam, respectively. The extraction yield of TSP was increased significantly by EB and GR irradiation, but there was no significant difference between irradiation types. Morphological studies by scanning electron microscope showed that TSP from GR-irradiated tamarind seed had a fibrous structure, different from that of EB irradiated with a particle structures. The average molecular weight of TSP was decreased by the irradiation, and EB treatment degraded more severely than GR. Superoxide radical scavenging ability and total antioxidant capacity of EB-treated TSP showed higher than those of GR-treated TSP.

  3. Three-dimensional conformal partial breast external-beam irradiation after conservative surgery of the breast

    International Nuclear Information System (INIS)

    Objective: To explore the methods, dosimetric features and short-term effects of partial breast irradiation carried out by three-dimensional external-beam irradiation (3DCPBI) assisted by active breathing control (ABC). Methods: Computed tomography (CT) simulation assisted by active breathing control (ABC) was carried out for each patient and intended to get CT images in condition of 75% deepest inspiration named moderate deep inspiration breath hold (mDIBH). The extent labeled by the silver slips located in the cavity was delineated as gross target volume (GTV), GTV plus the margin of 15 mm was defined as planning target volume (PTV). 6 MV X-ray was selected as the radiation source and noncoplanar radiation with four three-dimensional conformal fields was used, the described dose was 34 Gy/10f/5d. The volume of GTV, PTV, the affected whole breast, and the percentage of PTV accounted for the affected whole breast, the percentages of PTV included by 100%, 95% and 90% isodose curve, the percentage of volume of the affected breast irradiated by 34.0, 27.2, 20.4, 13.6 and 6.8 Gy , and Dmean, D5, V20 of the lungs and heart were calculated respectively. Acute radiation skin response was recorded and the cosmetic effect of the breast after radiotherapy were appraised, with the local tumor control and survival rate followed. Results: The mean of volume ratio of PTV and affected whole breast was 14.88%; the mean of the volume covered by 90% isodose curve accounted for 92.54% of the PTV; the volume irradiated by 34 Gy (100% of described dose) accounted for 17.23% (mean) of the whole breast and 6.8 Gy (20% of described dose) for 46.11%, in other words, the volume covered by 20% of described dose was less than 50% of the whole breast. The Dmean, D5, V20 for the affected lateral lung were 1.97, 9.25 Gy and 1.58%, it was 0.20, 0.87 Gy, and 0% for the unaffected lateral lung. The Dmean, D5, V20 for the heart was 0.65 Gy, 2.82 Gy, and 0.85%. Zero grade of acute radiation skin

  4. Modifications in the structural and optical properties of nanocrystalline CaWO4 induced by 8 MeV electron beam irradiation

    Science.gov (United States)

    Aloysius Sabu, N.; Priyanka, K. P.; Ganesh, Sanjeev; Varghese, Thomas

    2016-06-01

    In this article we report the post irradiation effects in the structural and optical properties of nanocrystalline calcium tungstate synthesized by chemical precipitation and heat treatment. The samples were subjected to different doses of high-energy electron beam obtained from an 8 MeV Microton. Investigations using X-ray diffraction, scanning electron microscopy and Raman spectra confirmed changes in particle size and structural parameters. However, no phase change was detected for irradiated samples. The stretching/compressive strain caused by high energy electrons is responsible for the slight shift in the XRD peaks of irradiated samples. Modifications in the morphology of different samples were confirmed by scanning electron microscopy. Ultraviolet-visible absorption studies showed variations in the optical band gap (4.08-4.25 eV) upon electron-beam irradiation. New photoluminescence behaviour in electron beam irradiated nanocrystalline CaWO4 was evidenced. A blue shift of the PL peak with increase in intensity was observed in all the irradiated samples.

  5. In-situ XMCD evaluation of ferromagnetic state at FeRh thin film surface induced by 1 keV Ar ion beam irradiation and annealing

    Science.gov (United States)

    Matsui, T.; Aikoh, K.; Sakamaki, M.; Amemiya, K.; Iwase, A.

    2015-12-01

    Surface ferromagnetic state of FeRh thin films irradiated with 1 keV Ar ion-beam has been investigated by using soft X-ray Magnetic Circular Dichroism (XMCD). It was revealed that the Fe atoms of the samples were strongly spin-polarized after Ar ion-beam irradiation. Due to its small penetration depth, 1 keV Ar ion-beam irradiation can modify the magnetic state at subsurface of the samples. In accordance with the XMCD sum rule analysis, the main component of the irradiation induced ferromagnetism at the FeRh film surface was to be effective spin magnetic moment, and not to be orbital moment. We also confirmed that the surface ferromagnetic state could be produced by thermal annealing of the excessively ion irradiated paramagnetic subsurface of the FeRh thin films. This novel magnetic modification technique by using ion irradiation and subsequent annealing can be a potential tool to control the surface magnetic state of FeRh thin films.

  6. Safety Irradiation Parameters of Nd:Y