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Sample records for radiation vulcanization processes

  1. Radiation vulcanization of natural rubber latex sensitized with commercial gases

    International Nuclear Information System (INIS)

    Chirinos, H.; Lugao, A.

    2002-01-01

    The industrial activities using natural rubber latex are fully compatible with rural areas in Amazon and other places in Brazil, as well as in other tropical countries. However the classical sulfur vulcanization presents many occupational problems for the workers in rural areas. Radiation vulcanization of natural rubber latex is a much more friendly process as sulfur compounds are not needed for crosslinking, although chemicals as acrylate monomers, particularly multifunctional acrylates are still used as sensitizers for radiation processes. Two commercial gases, acetylene and butadiene, were selected as sensitizers for the radiation vulcanization of natural rubber latex instead of acrylates. These gases accelerate the crosslinking rates of the cure process and lower the radiation dose required to achieve vulcanization of natural rubber latex and improve the mechanical properties to reduce the tackiness of rubber goods. (author)

  2. Radiation vulcanization of natural rubber latex sensitized with commercial gases

    Energy Technology Data Exchange (ETDEWEB)

    Chirinos, H.; Lugao, A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    2002-07-01

    The industrial activities using natural rubber latex are fully compatible with rural areas in Amazon and other places in Brazil, as well as in other tropical countries. However the classical sulfur vulcanization presents many occupational problems for the workers in rural areas. Radiation vulcanization of natural rubber latex is a much more friendly process as sulfur compounds are not needed for crosslinking, although chemicals as acrylate monomers, particularly multifunctional acrylates are still used as sensitizers for radiation processes. Two commercial gases, acetylene and butadiene, were selected as sensitizers for the radiation vulcanization of natural rubber latex instead of acrylates. These gases accelerate the crosslinking rates of the cure process and lower the radiation dose required to achieve vulcanization of natural rubber latex and improve the mechanical properties to reduce the tackiness of rubber goods. (author)

  3. Development of rubber gloves by radiation vulcanization

    International Nuclear Information System (INIS)

    Makuuchi, K.; Yoshii, F.; Ishigaki, I.; Mogi, M.; Saito, T.

    1990-01-01

    The processes of radiation vulcanization and production of protective rubber gloves for radioactive contamination are described. A newly developed sensitizing system consisting of 5 phr 2-ethylhexyl acrylate and 1 phr carbon tetrachloride was used to vulcanize natural rubber latex at 12 kGy. Transparent and soft gloves were obtained from the radiation vulcanized latex by a coagulant dipping process. The mechanical properties of the gloves meet Japanese Industrial Standard specification for protective gloves. Combustion analysis of the gloves revealed that the amount of evolved sulfur dioxide and remaining ashes are less than those from commercially available rubber gloves. A trial usage of the gloves at a nuclear power plant showed that the gloves were easy to use for delicate work without undergoing fatigue. (author)

  4. Radiation vulcanization in Argentina

    International Nuclear Information System (INIS)

    Ferenaz, Guillermo W.; Smolko, Eduardo E.

    1999-01-01

    The possibilities of using in Argentina the radiation process to vulcanize natural latex are analyzed. Experimental studies to define the irradiation conditions have been carried out and the preliminary elaboration of an irradiation device that includes the chemical reactor has been started. (author)

  5. Toxicological evaluation of natural rubber films from vulcanized latex by the conventional process and the alternative process with ionizing radiation

    International Nuclear Information System (INIS)

    Campos, Vania Elisabeth

    1997-01-01

    The industrial vulcanization of natural rubber latex (NRL) is made all over the world by conventional process using sulphur and heat but it can be made by an alternative process using ionizing radiation. In this research the NRL was tested by 13 physical, chemical and mechanical assays which showed its good quality. It was done a preliminary study of the toxicological properties of 4 natural rubber films obtained by casting process of NRL: one non vulcanized, other vulcanized by the conventional process and two vulcanized by the alternative process. In the alternative process the films were obtained by irradiation of NRL by gamma rays from the 60 Co source at 250 kGy in the absence of sensitizer and irradiated NRL at 12 kGy in the presence of 4ph r of n-butyl acrylate / 0.2 phr of KOH. These vulcanization doses were determined from broken tensile strength. In the conventional process, sulphur vulcanized NRL was made using a classical composition. Another film was made with non vulcanized NRL. The preliminary evaluation of the toxicological properties was made from in vitro cytotoxicity and in vivo systemic toxicity assays. The LBN films vulcanized by the alternative process have less cytotoxicity than the NRL film vulcanized by the conventional process. The sensitized vulcanized films by gamma rays and non vulcanized films showed similar cytotoxicity while the vulcanized films without sensitizer showed a slight lower cytotoxicity. The non vulcanized NRL film and the NRL films vulcanized by the alternative process did not show toxic effects int he 72 hours period of the systemic toxicity assay. However the NRL film vulcanized with sulphur induced effects like allaying and motor in coordination on the animals treated with an oil extract at the fourth hour and recovering after that. The alternative process promoted lower toxic effects than conventional process because there was no toxic substances present. (author)

  6. Biodegradability and aging study of rubber films obtained by gamma radiation vulcanization processes of latex

    International Nuclear Information System (INIS)

    Martins, Carlos Felipe Pinto

    2005-01-01

    The natural rubber latex (NRL) is industrially crosslinked by the conventional process of vulcanization, which uses sulphur and heat. Otherwise, the network can also be done by the alternative process with ionizing radiation. In this work the crosslinking of NRL was studied by the comparison of the conventional vulcanization system and the ionizing radiation process of 60 C source. The products obtained, the irradiated latex, the irradiated latex with approximately 1% of soy lecithin and the sulphur vulcanized latex were tested by accelerated aging with ultraviolet (UV) and outdoor aging with compostage, tensile strength at break, swelling and gel fraction, fungi micro biota, scanning electron microscopy (SEM), infrared spectroscopy (FTIR) and thermogravimetry and differential scanning calorimetry analysis (TG and DSC). The results showed that the aging with microorganisms have a great influence in the physical properties of the samples. The thermal stability order observed showed that the sulphur vulcanized latex is more resistant, what is probably associated to a network more stable under the aging conditions. On the other hand, the irradiated latex showed intense biodegradation aspects, particularly with the presence of the soy lecithin. (author)

  7. Toxicological evaluation of natural rubber latex film vulcanized with ionizing radiation

    International Nuclear Information System (INIS)

    Campos, Vania E.; Higa, Olga Z.; Guedes, Selma M.L.; Hanada, Seico

    1999-01-01

    The industrial vulcanization of natural rubber latex (NRL) is made worldwide by conventional process using sulphur, but it can be made by an alternative process using ionizing radiation. The main advantages of this process are related to absence of toxic effect promoted by chemical substances added to the NRL on the conventional process. In this research was tested the toxicological properties of the films vulcanized by the alternative process in relation to that vulcanized by the conventional process. The toxicity was evaluated by in vitro cytotoxicity assay and in vivo systemic toxicity assay. The results showed that vulcanized films by gamma ray are less cytotoxic. The systemic toxicity assay showed that only the vulcanized film using sulphur induced allaying and motor in coordination on the animals for a short period of time. these results evidence the less cytotoxic properties of vulcanized films by gamma ray in relation to that vulcanized by conventional process using sulphur. (author)

  8. Pilot scale experiments on radiation vulcanization of NR latex

    International Nuclear Information System (INIS)

    Ridwan, M.

    1985-01-01

    The potential of irradiated latex as raw material of commercial use is under testing on pilot plant scale in Indonesia which has 225 kCi Co-60 irradiation facility and can irradiate 1000 tonnes of centrifuged latex per annum. The facility was jointly designed by BATAN of Indonesia and JAERI of Japan and was jointly financed by UNDP/IAEA, Government of Japan and Government of Indonesia under UNDP/IAEA Regional Cooperative Agreement Project on Industrial Application of Isotopes and Radiation Technology. The facility is a water pool type and can accommodate 400 kCi Co-60. The Co-60 rack has two shapes, plate and cylindrical shapes. The plate shape source is used for natural rubber latex irradiation and the cylindrical one is used for other irradiation services. The vulcanization system consists of three major components: emulsification unit, mixing unit and vulcanization reactor. The first two components are located outside shielded room while the third one in irradiation room. The radiation vulcanization process is a much simpler energy saving process compared to the conventional thermal process which has two vulcanization steps before and after dipping. The physical and mechanical properties of irradiated NR latex are comparable to those of sulfur vulcanized. (author)

  9. Proceedings of the international symposium on radiation vulcanization of natural rubber latex

    International Nuclear Information System (INIS)

    Machi, Sueo

    1990-01-01

    The First International Symposium on Radiation Vulcanization of Natural Rubber Latex (RVNRL) was held from 26 to 28 July 1989 at Tokyo and Takasaki. In these proceedings, thirty six papers presented at the Symposium are compiled. Main topics are commercial application of RVNRL, characterization of NR latex and vulcanization, properties of radiation vulcanized NR latex, development of sensitizers, mechanism of RVNRL, RVNRL with electron beams, and new Co-60 irradiator for RVNRL. Absence of nitrosamines and low cytotoxicity of radiation vulcanized NR latex are recognized as the remarkable advantages of RVNRL. The radiation vulcanization process for the production of protective rubber gloves for radioactive contamination was presented as the first commercial success in RVNRL. It was reported that various kinds of rubber articles for medical uses have being developed in West Germany. A sensitizer system consisting of n-butyl acrylate and t-butyl hydroperoxide was found to reduce the vulcanization dose to 8 kGy. (author)

  10. Development of an efficient process for radiation vulcanization of natural rubber latex using hydroperoxide with sensitizer

    International Nuclear Information System (INIS)

    Siri-upathum, C.; Sonsuk, M.

    1996-01-01

    An attempt was made to reduce irradiation dose for radiation vulcanization of natural rubber latex. A promising method was to partially crosslink the latex by radiation vulcanization using n-butyl acrylate (n-BA) as sensitizer and t-butyl hydroperoxide (BHPO) as a co-sensitizer followed by redox vulcanization using residual BHPO as an oxidant and either fructose or tetra ethylene penta mine as reducing agents. It was found that the irradiation dose was reduced to 4 kGy with 5 phr n-BA as sensitizer and 0.1 phr BHPO as co-sensitizer. Successive crosslinking to full vulcanization was done by redox vulcanization using either 4 phr fructose at 60 degree C for 3 hours of 0.4 phr tetra-ethylene penta mine at room temperature for 1 hour. The rubber films obtained had tensile strength of about 25 MPa, modulus 300% of 0.9 MPa and crosslink density of about 1.5 x 10 19 crosslink/cm 3 . It was noted that the rubber film from the co-vulcanization was the average value of the values obtained by radiation vulcanization and redox vulcanization

  11. Pilot scale experiments on radiation vulcanization of NR latex

    Science.gov (United States)

    Ridwan, M.

    The potential of irradiated latex as raw material of commercial use is under testing on pilot plant scale in Indonesia which has 225 kCi Co-60 irradiation facility and can irradiate 1000 tonnes of centrifuged latex per annum. The facility was jointly designed by BATAN of Indonesia and JAERI of Japan and was jointly financed by UNDP/IAEA, Government of Japan and Government of Indonesia under UNDP/IAEA Regional Cooperative Agreement Project on Industrial Application of Isotopes and Radiation Technology. The facility is a water pool type and can accomodate 400 kCi Co-60. The Co-60 rack has two shapes, plate and cylindrical shapes. The plate shape source is used for natural rubber latex irradiation and the cylindrical one is used for other irradiation services. The vulcanization system consists of three major components : emulsification unit ( height : 650 mm, diameter 500 mm ), mixing unit ( height : 1900mm, diameter 1200 mm ) and vulcanization reactor ( height : 1800 mm, diameter 1300 mm ). The first two components are located outside shielded room while the third one-in irradiation room. The radiation vulcanization process is a much simpler energy saving process comparedto the conventional thermal process which has two vulcanization steps before and after dipping. The physical and mechanical properties of irradiated NR Latex are comparable to those of sulfur vulcanized, and depend on many factors such as irradiation dose, sensitizer content, dry rubber content and storage time.

  12. The mechanical properties of radiation-vulcanized NR/BR blending system

    Energy Technology Data Exchange (ETDEWEB)

    Yan Aoshuang E-mail: yanas@public3.bta.net.cn; Guo Zhengtao; Li Li; Zhai Ying; Zhou Peng

    2002-03-01

    The effect of radiation dose on the mechanical properties of NR/BR blending system is reported in this paper. A comparison was made between sulphur vulcanization and radiation vulcanization for an optimal nature rubber (NR)/ butyl rubber (BR) blending ratio (60/40) at dose range from 10 to 150 kGy. The result shows that the mechanical properties, especially, tensile strength, elongation at break, and tear strength have been improved significantly by radiation-vulcanization. This finding was also proved by thermal aging experiment on a selected NR/BR blend at 70 deg. C for up to 168 h.

  13. Progress in radiation vulcanization of natural rubber latex

    International Nuclear Information System (INIS)

    Makuuchi, Keizo

    2000-01-01

    Vulcanization dose defined as the radiation dose at which cross-linked natural rubber in latex has the maximum tensile strength can be reduced by adding carbon tetrachloride as a reaction accelerator. The radiation vulcanization of natural rubber latex was selected as one of regional projects of IAEA in 1989 and a pilot plant was built in Jakarta. The products from it were evaluated during 1983-1985, followed by IAEA decision to support the continued R and D study at Takasaki, JAERI. Various factors to improve the properties of the products have been studied. Several advantages of the process over conventional method, such as absence of N-nitrosoamines, low cytotoxicity, decomposability in the environment, transparency and softness, were confirmed. The technology has been transferred toward commercial application in Thailand, and pilot plants being set up in Indonesia, India, Malaysia and Thailand. Moreover, the process was found to be effective in reducing protein remaining in natural rubber latex products and the initial investment and irradiation cost was found to be greatly reduced by employing low energy electron accelerator. This paper reviews such progress. (S. Ohno)

  14. Extractable protein content of radiation vulcanized natural rubber latex films

    International Nuclear Information System (INIS)

    Ma'zam Md Said; Wan Manshol Wan Zin

    1996-01-01

    The effects of processing conditions on extractable protein content of coagulant dipped radiation vulcanized natural rubber latex films have been investigated. Drying of wet-gel of radiation vulcanized latex films even at a relatively low temperature of 70 degree C resulted in increases of extractable protein content of the films. The extractable protein content is dependent upon both the temperature and time of drying of wet-gel deposit. Wet-gel leaching of film alone is not adequate to reduce the extractable protein content of films to low levels. Combination of wet-gel leaching, post-leaching, a dip in corn starch slurry, followed by drying at a low temperature of 70 degree C reduces the extractable protein content of films to very low levels

  15. Aspects of Degradability and Aging of Natural Rubber Latex Films Obtained by Induced Ionizing Radiation Processes of Latex Vulcanization

    International Nuclear Information System (INIS)

    Parra, D. F.

    2006-01-01

    This study refers to the degradability of NRLF, natural rubber latex films, obtained by ionizing radiation. Three types of NRLF were prepared: irradiated latex, irradiated latex with about 1% of soy lecithin and sulfur-vulcanized latex, by cold vulcanization process. The films were buried in vases of two different kinds of soil: common soil and common soil with earthworm humus. Fast aging tests in laboratory with exposition to ultraviolet rays were done in irradiated latex films and irradiated latex films with soy lecithin. The results obtained after ten months of tests with buried films agree with the results of the fast aging tests, showing singularities of each type of soil and each kind of latex process. It also shows how weather inclemency can induce the films degradation process. The sulfur-vulcanized films were weakly degraded when buried. The films with lecithin and buried in vase with only common soil showed the biggest mass loss, but the films with lecithin buried in vases with common earthworm humus and soil increased their weigh and dimensions due to fungi formation. The irradiated latex films are more degradable then the sulfur-vulcanized films. The irradiated latex film, unlike the sulfur vulcanized film, showed high fungi colonization when buried. We conclude that the irradiated latex films are more easily biodegradable than the sulfur vulcanized latex films. The biodegradability increases with the addition of small amounts of soy lecithin (∼1%). The mechanical resistance of the buried films decreased related to the non-buried ones, proving that the outdoor aging in soil and the presence of fungi in the films can modify the mechanical properties of the irradiated latex owing to the biodegradation

  16. Analysis of Aqueous Extractable Protein in Radiation Pre vulcanized Natural Rubber Latex (RVNRL) And Sulphur Pre vulcanized Natural Rubber Latex (SVNRL)

    International Nuclear Information System (INIS)

    Sofian Ibrahim; Mohd Noor Wadi Mat Lazim; Syuhada Ramli; Keong, C.C.; Khairul Hisyam Mohd Yusof; Muhammad Saiful Omar; Najib Mohd Zakey; Hafizuddin Maseri; Noor Hasni Mohd Ali

    2015-01-01

    The use of radiation do not only produces Radiation Pre vulcanized Natural Rubber Latex (RVNRL) that can be used for the production of nitrosamines free products, moreover, RVNRL also able to exclude type IV allergy that caused by high protein content in the products. Leaching water from production of finger coat from RVNRL and Sulphur Pre vulcanized Natural rubber Latex (SVNRL) has been collected. Extractable protein content from water samples measured according to the test protocol ASTM D5712-2010. Water from leaching process of finger coat made from RVNRL showed a higher protein content than SVNRL. This explains why RVNRL based products contain very low protein content and thus reduce the risk of Type IV allergy. (author)

  17. Comparative studies on sulfur, peroxide, and radiation vulcanization of EFDM rubber

    International Nuclear Information System (INIS)

    Abdel-Aziz, M.M.; Basfar, A.A.; Mofti, S.

    2000-01-01

    The temperature and concentration dependence of the vulcanization characteristics and mechanical properties of epdm rubber containing various concentrations of peroxide compounds was studied. The peroxides used are Luperox Di, Luperox 500-40 Ke, peroximon Dc Sc and peroximon Dc 40 Ke. The optimum cure parameters for the different types of peroxides indicated that Luperox Di, relatively, Give the best properties among the studied peroxides. The mechanical properties of EPDM containing different concentrations of Luperox Di and vulcanized at different temperatures were compared with those of either radiation or sulfur-cured EPDM. The modulus stress and tensile strength of the Luperox Di-cured EPDM were found to increase with either increasing the temperature of vulcanization and/ or concentration of the peroxide. Moreover, the tensile strength values are much higher than those of the sulfur-cured samples, except for those with low concentration of peroxide and vulcanized at relatively low temperature. A comparable result to those of the chemically vulcanized samples was attained by the radiation- vulcanized samples containing 1 phr of crosslinking agent and irradiated to 150 KGy

  18. Radiation processed polychloroprene-co-ethylene-propene diene terpolymer blends: Effect of radiation vulcanization on solvent transport kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, K.A. [Radiation Technology Development Section, Bhabha Atomic Research Centre, Room No. S-1, HIRUP Building, Trombay, Mumbai 400 085 (India); Bhardwaj, Y.K. [Radiation Technology Development Section, Bhabha Atomic Research Centre, Room No. S-1, HIRUP Building, Trombay, Mumbai 400 085 (India)], E-mail: ykbhard@barc.gov.in; Chaudhari, C.V.; Kumar, Virendra; Goel, N.K.; Sabharwal, S. [Radiation Technology Development Section, Bhabha Atomic Research Centre, Room No. S-1, HIRUP Building, Trombay, Mumbai 400 085 (India)

    2009-03-15

    Blends of polychloroprene rubber (PCR) and ethylene propylene diene terpolymer rubber (EPDM) of different compositions were made and exposed to different gamma radiation doses. The radiation sensitivity and radiation vulcanization efficiency of blends was estimated by gel-content analysis, Charlesby-Pinner parameter determination and crosslinking density measurements. Gamma radiation induced crosslinking was most efficient for EPDM (p{sub 0}/q{sub 0} {approx} 0.08), whereas it was the lowest for blends containing 40% PCR (p{sub 0}/q{sub 0} {approx} 0.34). The vulcanized blends were characterized for solvent diffusion characteristics by following the swelling dynamics. Blends with higher PCR content showed anomalous swelling. The sorption and permeability of the solvent were not strictly in accordance with each other and the extent of variation in two parameters was found to be a function of blend composition. The {delta}G values for solvent diffusion were in the range -2.97 to -9.58 kJ/mol and indicated thermodynamically favorable sorption for all blends. These results were corroborated by dynamic swelling, experimental as well as simulated profiles and have been explained on the basis of correlation between crosslinking density, diffusion kinetics, thermodynamic parameters and polymer-polymer interaction parameter.

  19. Continuous vulcanization of extruded profile by microwave process

    International Nuclear Information System (INIS)

    Lim Hun Soo

    1994-01-01

    Continuous vulcanization is being increasingly used today in the manufacture of extrusion profiles. This is particularly so with the microwave/hot air continuous vulcanization process. Although this process is now quite widely used in Europe and to a lesser extent in USA, it is still not used in Malaysia. To improve the technological capability of the rubber-based industry in extrusion product, the RRIM has acquired a microwave/hot air tunnel continuous vulcanization equipment to enable development work in this area to be carried out with the aim of upgrading the rubber industry towards this more automated manufacturing process. This is particularly pertinent in view of the anticipated labour shortage, and, increasing labour and energy cost. This paper outlines the basic principles of operation of the microwave/hot air tunnel continuous vulcanization process and describes some aspects of compounding involving natural and synthetic rubbers for use in the process. As temperature increase is one of the major factors influencing the vulcanization of profile in this process, study was therefore concentrated on the heat generation aspect in the microwave tunnel

  20. Mechanism of n-butyl acrylate sensitization action in radiation vulcanization of natural rubber latex

    International Nuclear Information System (INIS)

    Sabharwal, S.; Chaudhari, C.V.; Bhardwaj, Y.K.; Majali, A.B.; Das, T.N.

    1996-01-01

    In order to understand the role of n-butyl acrylate (nBA) in radiation vulcanization of natural rubber latex, pulse radiolysis technique has been utilized to study the reactions of the transient species produced by reaction of OH . , e- aq and H . atoms with nBA in aqueous solutions. The results show that transients produced by reaction of e- aq with nBA alone are capable of propagating the polymerization reaction and enhance the vulcanization process. These results have been further confirmed by studying the effect of electron scavengers on the vulcanization behaviour of natural rubber latex in presence of nBA. (author). 3 refs., 3 figs

  1. The influence of radiolytic sensitizers in natural rubber latex vulcanization induced by ionizing radiation

    International Nuclear Information System (INIS)

    Guedes, S.M.L.; Souza, A. de

    1991-01-01

    This work made on radiation vulcanization of natural rubber latex process by gamma rays from 60 Co source and electron beam of 1.5 MeV, 25 m A by Dynamitron, instead of classic process using sulfur. The experiment was carried out to study the influence of sensitizers (C Cl 4 and n-butyl acrylate) and was reported the vulcanization dose for each sensitizers, related to maximum tensile strength. The results show the possibility to introduce the volatile sensitizer (n-butyl acrylate) instead of C Cl 4 (toxic) in industry applications. (author)

  2. Radiation vulcanization of natural rubber latex

    International Nuclear Information System (INIS)

    Wan Manshol bin Wan Zin; Norjanah binti Mohid

    1994-01-01

    This paper describes the experimental techniques and the results of radiation vulcanization of natural rubber latex carried out on several high ammonia latices available in the country. The efficiency of various sensitisers and stabilisers used were evaluated in terms of the gamma radiation dose required to produce the maximum tensile strengths. The extent of crosslinking of RVNRL sample films were estimated by equilibrium swelling ratio measurements. The stability of pre-irradiated and post-irradiated samples were monitored using viscosity measurements as the parameter

  3. Toxicological evaluation of natural rubber films from vulcanized latex by the conventional process and the alternative process with ionizing radiation; Avaliacao toxicologica de filmes de borracha natural obtidos do latex vulcanizado pelo processo convencional e pelo processo alternativo com radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Vania Elisabeth

    1997-07-01

    The industrial vulcanization of natural rubber latex (NRL) is made all over the world by conventional process using sulphur and heat but it can be made by an alternative process using ionizing radiation. In this research the NRL was tested by 13 physical, chemical and mechanical assays which showed its good quality. It was done a preliminary study of the toxicological properties of 4 natural rubber films obtained by casting process of NRL: one non vulcanized, other vulcanized by the conventional process and two vulcanized by the alternative process. In the alternative process the films were obtained by irradiation of NRL by gamma rays from the {sup 60} Co source at 250 kGy in the absence of sensitizer and irradiated NRL at 12 kGy in the presence of 4ph r of n-butyl acrylate / 0.2 phr of KOH. These vulcanization doses were determined from broken tensile strength. In the conventional process, sulphur vulcanized NRL was made using a classical composition. Another film was made with non vulcanized NRL. The preliminary evaluation of the toxicological properties was made from in vitro cytotoxicity and in vivo systemic toxicity assays. The LBN films vulcanized by the alternative process have less cytotoxicity than the NRL film vulcanized by the conventional process. The sensitized vulcanized films by gamma rays and non vulcanized films showed similar cytotoxicity while the vulcanized films without sensitizer showed a slight lower cytotoxicity. The non vulcanized NRL film and the NRL films vulcanized by the alternative process did not show toxic effects in the 72 hours period of the systemic toxicity assay. However the NRL film vulcanized with sulphur induced effects like allaying and motor in coordination on the animals treated with an oil extract at the fourth hour and recovering after that. The alternative process promoted lower toxic effects than conventional process because there was no toxic substances present. (author)

  4. Radiation vulcanization of ethylene-propylene rubber with polyfunctional monomers

    Energy Technology Data Exchange (ETDEWEB)

    Jinhua, Wang; Yoshii, Fumio; Makuuchi, Keizo

    2001-01-01

    This paper reports on the sensitizing efficiency of several polyfunctional monomers to radiation vulcanization of ethylene-propylene rubber. And the results show that triethyleneglycol dimethacrylate (TEGDMA) gave the best results. TEGDMA not only lowers the vulcanization dose (D{sub v}), but also increases the tensile strength greatly. The content of TEGDMA does not affect the D{sub v} of TEGDMA-EPM, but affects the tensile strength at the D{sub v}. At best content (0.04 mol/100 g EPM), the tensile strength is increased from 6.0 to 12 MPa, and the elongation is 790% at the D{sub v}. (author)

  5. Research and application of fuzzy subtractive clustering model on tensile strength of radiation vulcanization for nitrile-butadiene rubber

    International Nuclear Information System (INIS)

    Zuo Duwen; Wang Hong; Zhu Nankang

    2010-01-01

    By use of fuzzy subtractive clustering model, the relationship between tensile strength of radiation vulcanization of NBRL (Nitrile-butadiene rubber latex) and irradiation parameters have been investigated. The correlation coefficient was calculated to be 0.8222 in the comparison of experimental data to the predicted data. It was obvious that fuzzy model identification method is not only high precision with small computation, but also easy to be used. It can directly supply the evolution of tensile strength of NBR by fuzzy modeling method in radiation vulcanization process for nitrile-butadiene rubber. (authors)

  6. Radiation vulcanization of natural rubber latex using 250 keV electron beam machine

    Energy Technology Data Exchange (ETDEWEB)

    Chirinos, H.; Yoshii, F.; Makuuchi, K.; Lugao, A. E-mail: ablugao@net.ipen.br

    2003-08-01

    The sensitized radiation vulcanization of natural rubber latex has been carried out with 250 keV electrons. Latex was irradiated over a range of the beam current from 5 to 20 mA in the presence of sensitizers like the n-butyl acrylate (n-BA). The vulcanization dose decreases with increasing beam current condition. The rate of vulcanization (R{sub vul}) depends on the beam current (I) as given by the equation R{sub vul}=kI{sup 0.6}.

  7. Radiation vulcanization of Philippine natural rubber latex

    International Nuclear Information System (INIS)

    Dela Rosa, Alumanda M.; Abad, Lucille V.; Sta, Lorna P.; Ana-Relleve; Tranquilan-Aranilla, Charito O.; Pascual, Cristina L.

    1996-01-01

    produced and processed in the Philippines is suited for radiation vulcanization

  8. Efficiency of 1,9- Nonane-diol-diacrylate as a radiation vulcanization accelerator for natural rubber latex

    International Nuclear Information System (INIS)

    Haque, M.E.

    2003-09-01

    The efficiency of 1,9- Nonane-diol-diacrylate (NDDA) as a radiation vulcanization accelerator (RVA) for natural rubber latex (NRL) was investigated. Both gamma rays and electron beam (EB) were used for vulcanizing NRL with NDDA. The radiation dose of gamma rays, concentration of NDDA required to vulcanize the latex were optimized. 20 kGy radiation dose of gamma rays and 5 phr concentration of NDDA were found optimum to get maximum tensile and related properties. NRL was vulcanized under EB to find out the optimum condition of irradiation with this RVA. The defoamer concentrations, length of irradiation time under EB, concentration of RVA were optimizer by changing various parameters of the EB machine with a constant set of the others. 0.2 phr defoamer concentration, 30 minutes irradiation time and 5 phr concentration of NDDA were found optimum for irradiation of NRL under the EB machine. Effect of low current and optimum volume of latex charged in the reaction vessel suitable for vulcanization at a time were found out. (author)

  9. Application of radiation vulcanized natural rubber latex in Indonesia

    International Nuclear Information System (INIS)

    Soebianto, Y.S.; Wiwik Sofiarti; Razzak, M.T.

    1996-01-01

    The center has carried out R and D of Radiation Vulcanization Natural Rubber Latex (RVNRL) technology and introduced it to the industries since the inauguration and operation of the latex pilot plant in 1983. After years of experiences and the environmental consideration, n-butylacrylate (n-BA) has replaced CCI, as the sensitizer. Until now the introduction program shows that radiation vulcanized latex is more suitable for home industries than large industries. The obstacle of the program is the marketing of the dipped products. In spite of these problems, the introduction of this technology to the people in some undeveloped area of Java has supported the national program to improve their living standard. The problems of nitrosamine and protein allergic have turn up RVNRL to be the substitute of sulfur vulcanized latex in the future. The cooperation with a national condom manufacturer (PT Mitra Banjaran) has applied RVNRL for condom production in the large scale. Soft condoms with less probability of pinhole are obtained, but the technical problem is stickiness after pilling. Supply to a baby teat and a rubber thread manufacturer offers great advantages by not using any chemicals. In spite of the advantages, the problem of latex viscosity for dipping and the low modulus of elasticity of the threads arise. Through those input CAIR-BATAN is conducting the research and development in improving the crosslinking among the rubber particles that are supposed to be the reason of the stickiness and low modulus of elasticity. This effort is expected to be able to broaden the application of RVNRL, and it will be achieved only by the involvement of rubber chemist, rubber technologist, and radiation chemist

  10. Radiation vulcanization of natural rubber latex with low energy accelerator-II

    Energy Technology Data Exchange (ETDEWEB)

    Haque, Md. Emdadul; Makuuchi, Keizo; Ikeda, Kenichi; Yoshii, Fumio; Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Mitomo, Hiroshi [Gunma Univ., Faculty of Engineering, Dept. of Biological and Chemical Engineering, Kiryu, Gunma (Japan)

    2002-03-01

    The natural rubber latex (NRL) was radiation vulcanized under a low energy electron accelerator. Accelerating voltage and maximum beam current of this accelerator are 250 kV and 10 mA respectively. Irradiation was carried out in a reaction vessel with constant stirring. The capacity of the vessel is 18 liters. Radiation vulcanization accelerators (RVA) were normal butyl acrylate (n-BA) and nonane-diol-diacrylate (NDDA). NDDA has no bad smell like that of n-BA. 20 minutes irradiation time is enough to vulcanize 14 liters of latex when 5 phr RVA (both types) are used. Maximum of {approx}30 MPa tensile strength was obtained with 5 phr NDD-A. However the remained NDDA is difficult to remove due to high molecular weight. Water-extractable proteins content was determined in dipped films for various leaching conditions without and with additive (polyvinyl alcohol, PVA). Water extractable proteins content is reduced to {<=} 41 by adding 5 phr PVA and leaching for 8 hours. The tackiness of the dipped films is reduced to 0.1 from 9 gf by mixing 6 phr PVA with the irradiated latex. Hand gloves (surgical and examination) were successfully produced from the irradiated latex. (author)

  11. Evaluation of electron beam irradiation under heating process on vulcanized EPDM

    International Nuclear Information System (INIS)

    Gabriel, Leandro; Cardoso, Jessica R.; Moura, Eduardo; Geraldo, Aurea B.C.

    2015-01-01

    The Global consumption of rubber is estimated around 30.5 million tons in 2015, when it is expected an increase of 4.3% of this volume in the coming of years. This demand is mainly attributed to the production of elastomeric accessories for the automotive sector. However, the generation of this type of waste also reaches major proportions at the end of its useful life, when it is necessary to dispose the environmental liability. Rubber reprocessing is an alternative where it can be used as filler in other polymer matrices or in other types of materials. The devulcanization process is another alternative and it includes the study of methods that allow economic viability and waste reduction. Therefore, this study aims to recycle vulcanized EPDM rubber with the use of ionizing radiation. In this work we are using the electron beam irradiation process with simultaneous heating at absorbed doses from 150 kGy to 800 kGy, under high dose rate of 22.3 kGy/s on vulcanized EPDM powder and on samples about 4 mm thick. Their characterization, before and after the irradiation process, have been realized by thermal analysis and their changes have been discussed. (author)

  12. Evaluation of electron beam irradiation under heating process on vulcanized EPDM

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, Leandro; Cardoso, Jessica R.; Moura, Eduardo; Geraldo, Aurea B.C., E-mail: lgabriell@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The Global consumption of rubber is estimated around 30.5 million tons in 2015, when it is expected an increase of 4.3% of this volume in the coming of years. This demand is mainly attributed to the production of elastomeric accessories for the automotive sector. However, the generation of this type of waste also reaches major proportions at the end of its useful life, when it is necessary to dispose the environmental liability. Rubber reprocessing is an alternative where it can be used as filler in other polymer matrices or in other types of materials. The devulcanization process is another alternative and it includes the study of methods that allow economic viability and waste reduction. Therefore, this study aims to recycle vulcanized EPDM rubber with the use of ionizing radiation. In this work we are using the electron beam irradiation process with simultaneous heating at absorbed doses from 150 kGy to 800 kGy, under high dose rate of 22.3 kGy/s on vulcanized EPDM powder and on samples about 4 mm thick. Their characterization, before and after the irradiation process, have been realized by thermal analysis and their changes have been discussed. (author)

  13. Radiation vulcanization of Philippine natural rubber latex

    International Nuclear Information System (INIS)

    Dela Rosa, A.M.; Abad, L.V.; Sta.Ana-Relleve, L.P.; Tranquilan-Aranilla, C.O.; Pascual, C.L.

    1996-01-01

    The response of Philippine natural rubber latex to irradiation vulcanization and the stability of the irradiated natural rubber latex (INRL) upon storage and aging were investigated. Commercially available high ammonia (HA) concentrated latices obtained from various rubber plantations in Mindanao island were treated with 5 phr of n-butyl acrylate (nBA), and gamma-irradiated at the PNRI 60 Co irradiation facility at a dose rate of 2.57 kGy/hr. Unirradiated cast latex films gave different green strengths which varied from 2-11 MPa. Cast films from INRL exhibited maximum tensile strengths were obtained from cast films with low Mg and high nitrogen contents. Thermal analysis using thermogravimetry (TG) revealed one major decomposition product at 374 o -377 o C. Its rate of decomposition decreased to a minimum at 15 kGy, then increased as radiation dose was increased. This trend correlated well with the tensile strength measurements. The stability of the INRL upon storage and aging is an essential parameter to the rubbe latex industry. For storage studies, INRL was stored for various periods of time. It was found that the pH and total solids content of the stored INRL did not change significantly after 12 months of storage; the MST values remained at above 1000 seconds, and the viscosity decreased with time. The cast films exhibited a decline in tensile strength, modulus 300% , and crosslinking density upon storage. While there were observed changes in the physical properties of the INRL during the storage period, the data indicate that these properties were within values acceptable to the latex industry. Tests on the aging properties of INRL films were undertaken. It was shown that among the chemical antioxidants presently used by the latex industry, TNPP demonstrated the highest antioxidant property, followed by Antage DAHQ and Vulcanox BKF. Our data indicate that the natural rubber latex produced and processed in the Philippines is suited for radiation vulcanization

  14. Biodegradability and aging study of rubber films obtained by gamma radiation vulcanization processes of latex; Estudo da biodegradabilidade e envelhecimento de filmes de borracha obtidos por processos de vulcanizacao do latex por radiacao induzida de fonte gama

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Carlos Felipe Pinto

    2005-07-01

    The natural rubber latex (NRL) is industrially crosslinked by the conventional process of vulcanization, which uses sulphur and heat. Otherwise, the network can also be done by the alternative process with ionizing radiation. In this work the crosslinking of NRL was studied by the comparison of the conventional vulcanization system and the ionizing radiation process of {sup 60}C source. The products obtained, the irradiated latex, the irradiated latex with approximately 1% of soy lecithin and the sulphur vulcanized latex were tested by accelerated aging with ultraviolet (UV) and outdoor aging with compostage, tensile strength at break, swelling and gel fraction, fungi micro biota, scanning electron microscopy (SEM), infrared spectroscopy (FTIR) and thermogravimetry and differential scanning calorimetry analysis (TG and DSC). The results showed that the aging with microorganisms have a great influence in the physical properties of the samples. The thermal stability order observed showed that the sulphur vulcanized latex is more resistant, what is probably associated to a network more stable under the aging conditions. On the other hand, the irradiated latex showed intense biodegradation aspects, particularly with the presence of the soy lecithin. (author)

  15. Extractable protein of radiation vulcanized natural rubber latex

    International Nuclear Information System (INIS)

    Soebianto, Y.S.; Upul, R.M.; Makuuchi, K.; Yoshii, F.; Kume, T.

    2000-01-01

    A new method to reduce the protein level in the latex products by irradiation is reported. Water soluble protein (WSP) solution (10%) was added into radiation vulcanized NR latex (RVNRL) as much as 3 phr in three different processes: added to RVNRL, added to re-centrifuged RVNRL, and added to RVNRL followed by centrifugation. The protein content was determined by enhanced BCA method, and identified by SDS-PAGE analysis. Addition of WSP followed by centrifugation reduces EP up to the minimum protein detection, and shortens the leaching time to 20-30 min. SDS-PAGE analysis confirms the reduction of soluble protein in the serum phase, and disappearance of protein bands in the rubber extract. Protein-WSP interaction produces water soluble complex, and removed by centrifugation. The molecular weight of WSP dictates the efficiency of protein removal. (author)

  16. Extractable protein of radiation vulcanized natural rubber latex

    Energy Technology Data Exchange (ETDEWEB)

    Soebianto, Y.S. [Center for Research and Development of Isotopes and Radiation Technology, BATAN, Jakarta (Indonesia); Upul, R.M. [Rubber Research Institute of Sri Lanka, Ratmalana (Sri Lanka); Makuuchi, K.; Yoshii, F.; Kume, T. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2000-03-01

    A new method to reduce the protein level in the latex products by irradiation is reported. Water soluble protein (WSP) solution (10%) was added into radiation vulcanized NR latex (RVNRL) as much as 3 phr in three different processes: added to RVNRL, added to re-centrifuged RVNRL, and added to RVNRL followed by centrifugation. The protein content was determined by enhanced BCA method, and identified by SDS-PAGE analysis. Addition of WSP followed by centrifugation reduces EP up to the minimum protein detection, and shortens the leaching time to 20-30 min. SDS-PAGE analysis confirms the reduction of soluble protein in the serum phase, and disappearance of protein bands in the rubber extract. Protein-WSP interaction produces water soluble complex, and removed by centrifugation. The molecular weight of WSP dictates the efficiency of protein removal. (author)

  17. Effects of radio sensitizers in the vulcanization of natural rubber latex induced by gamma radiation

    International Nuclear Information System (INIS)

    Souza, A. de; Canavel, V.; Araujo, S.C. de; Guedes, S.M.L.

    1992-01-01

    The effect of C Cl 4 and n-butyl acrylate as a sensitizer for radiation vulcanization of 60% DRC natural rubber latex with gamma rays, was studied relating tensile strength of vulcanized latex. The vulcanization dose is 200 kGy for natural rubber latex and it decreases to 40 kGy and to 9 kGy in the presence of C Cl 4 / potassium laureate and n-butyl acrylate / t-butyl hydroperoxide, respectively. The H 2 O 2 as a co-sensitizer does not change the efficiency of the combination of these sensitizers. The IV spectra show the formation of C=O after the irradiation as consequence of oxidation reactions. (author)

  18. Cost evaluation of radiation vulcanization of natural rubber latex

    International Nuclear Information System (INIS)

    Makuuchi, K.

    2003-01-01

    Cost of radiation vulcanized NR latex was evaluated. The plant would be built in an existing dipping factory in an industrial area in a Southeast Asian country. One thousands dry tons of NR latex are vulcanized with a low energy electron accelerator. The electron accelerator is a self-shielding low energy type. The maximum accelerating voltage is 300 kV and the output power is 10 kW. The total construction cost of the plant is $400,000 including electron accelerator and other equipments. Costs of raw materials and utilities are $1.165 and $0.023 per one kg of product, respectively. The fixed costs of the plant consist of labor costs, labor overhead, maintenance, plant overhead, depreciation, and bank interest. It is $0.190/kg of product. The company overhead for operation including company management, R and D and insurance is $0.044/kg of product. Thus, the total production cost is estimated to be $1.422/kg of product. (author)

  19. Test trial radiation vulcanization of natural rubber latex in Jakarta Indonesia

    International Nuclear Information System (INIS)

    Devendra, R.; Kulatunge, S.S.; Chandralal, H.N.K.K.; Kalyani, N.M.V.; Seneviratne, J.; Wellage, S.

    1994-01-01

    Radiation vulcanization of natural rubber latex (RVNRL) can be used to make large quantities of specially stabilized latex. It is possible to obtain RVNRL films of tensile strength over 25 MPa. The films could be either coagulant dipped or cast. It is very important to determine the correct radiation dose which gives the maximum tensile strength. Cross linking density or prevulcanized relax modulus (PRM) at 100% is a reliable property to control the prevulcanization

  20. Development of radiation processes for better environment

    International Nuclear Information System (INIS)

    Majali, A.B.; Sabharwal, S.; Deshpande, R.S.; Sarma, K.S.S.; Bhardwaj, Y.K.; Dhanawade, B.R.

    1998-01-01

    The increasing population and industrialization, worldover, is placing escalating demands for the development of newer technologies that are environment friendly and minimize the pollution associated with the development. Radiation technology can be of benefit in reducing the pollution levels associated with many processes. The sulphur vulcanization method for natural rubber latex vulcanization results in the formation of considerable amounts of nitrosoamines, both in the product as well as in the factory environment. Radiation vulcanization of natural rubber latex has emerged as a commercially viable alternative to produce sulphur and nitrosoamine free rubber. A Co-60 γ-radiation based pilot plant has been functioning since April 1993 to produce vulcanized natural rubber latex (RVNRL) using acrylate monomers as sensitizer. The role of sensitizer, viz. n-butyl acrylate in the vulcanization process has been elucidated using the pulse radiolysis technique. Emission of toxic sulphur containing gases form an inevitable part of viscose-rayon process and this industry is in search of ways to reduce the associated pollution levels. The irradiation of cellulose results in cellulose activation and reduction in the degree of polymerization (DP). These effects can reduce the solvents required to dissolve the paper pulp. There is a keen interest in utilizing radiation technology in viscose rayon production. We have utilized the electron beam (EB) accelerator for reducing the degree of polymerization (DP) of paper pulp. Laboratory scale tests have been carried out to standardize the conditions for production of pulp having the desired DP by EB irradiation. The use of irradiated paper pulp can result in ∼40% reduction in the consumption of CS 2 in the process that can be beneficial in reducing the pollution associated with the process. PTFE waste can be recycled into a low molecular weight microfine powder by irradiation. An EB based process has been standardized to produce

  1. Radiation Vulcanization of Natural Rubber Latex (RVNRL): A Potential Material for Nuclear Power Plant Gloves

    International Nuclear Information System (INIS)

    Pairu Ibrahim; Wan Manshol Wan Zain; Keong, C.C.; Mohd Noorwadi Mat Lazim

    2011-01-01

    Radiation vulcanization of natural rubber latex has great potential for the production of nuclear power plant gloves due to its low ash and mineral content. And this is in-line with the role played by Malaysian Nuclear Agency as Technical Supporting Organization for Nuclear Power Program. This paper discussed the evaluation done to determine ash content in RVNRL and SVNRL films. Both samples were prepared using casting technique and the properties were compared. Films prepared from raw latex without any vulcanizing agent were regarded as a control. (author)

  2. Radiation vulcanization of natural rubber latex with low energy accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Haque, Emdadul; Makuuchi, Keizo; Ikeda, Kenichi; Yoshii, Fumio; Kume Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Mitomo, Hiroshi [Gunma Univ., Faculty of Engineering, Department of Biological and Chemical Engineering, Kiryu, Gunma (Japan)

    2001-03-01

    The radiation vulcanization of natural rubber latex (RVNRL) with the recently installed electron beam (EB) pilot plant at Takasaki Radiation Chemistry Research Establishment, Takasaki, Japan has been discussed. The accelerating voltage and beam current of the plant are 250 kV and 10 mA respectively. The plant has a reaction vessel with the capacity of 18 liters latex to irradiate at a time. In order to obtain a suitable setting of experimental for RVNRL under EB of the plant the parameters such as irradiation time, defoamer concentration, volume of latex, beam current etc. are being optimized by varying the individual parameter at a constant set of the other variables. (author)

  3. Production of medical supplies from elastomers vulcanized with ionizing radiation

    International Nuclear Information System (INIS)

    Guedes, Selma M.L.; Collantes, Hugo David Chirinos; Kodama, Yasko

    1996-01-01

    The silicon was vulcanized by gamma rays in the absence of organic peroxides. The natural rubber latex was vulcanized by gamma rays and electron beams in the absence and presence of sensitizer. The surgical gloves fabricated with latex containing nB-A vulcanized by gamma rays can be commercialized. Another expected applications are the development of the catheter and the material utilized in the radiotherapy treatment. (author)

  4. Extractable protein of radiation vulcanized natural rubber latex

    International Nuclear Information System (INIS)

    Soebianto, Y.S.; Ratnayake, U.M.; Makuuchi, Keizo; Yoshii, Fumio; Kume, Tamikazu

    2000-01-01

    Protein remained in the latex products are reported to cause serious allergy. A new method to reduce the protein level in the latex products by irradiation is reported. Water soluble protein (WSP) solution (10%) was added into radiation vulcanized NR latex (RVNRL) in three different processes. The amount of WSP was 3 phr. It was only added to RVNRL (standard), added to re-centrifuged RVNRL (pre-centrifugation), and added to RVNRL followed by centrifugation (post-centrifugation). The protein content was determined by enhanced BCA method, and identified by SDS-PAGE. Extractable protein (EP) from the rubber has been reduced up to the minimum protein detection by combining WSP addition and centrifugation. Short leaching time (20-30 min.) can be achieved after the combine treatment, and SDS-PAGE confirms the reduction of soluble protein in the serum phase, and disappearance of protein bands in the rubber extract. Protein-WSP interaction produces water soluble complex, and removed by centrifugation. The efficiency of protein removal by WSP depends on its molecular weight of WSP which relates to its water solubility. (author)

  5. Radiation vulcanization of natural rubber latex using irradiation n-butyl acrylate aqueous emulsion as sensitizer

    International Nuclear Information System (INIS)

    Vo Van Thien; Nguyen Quoc Hien; Keizo Makuuchi; Fumio Yoshii

    2000-01-01

    Natural rubber latex was vulcanized by gamma radiation with n-butyl acrylate aqueous emulsion irradiated at dose of 1.5 kGy as sensitizer. The total solid content of latex increases on the irradiation dose. The viscosity of latex on the standing time was investigated and became stable after one month of storage. The gel content of latex films increasing with irradiation dose and attained more than 94% at dose of 10 kGy. Tensile strength of films reached the values of 31MPa; 30 Mpa and 25 Mpa at vulcanization doses of 20 kGy, 15 kGy and 8 kGy for the concentrations of sensitizer 7 phr, 9 phr and 13 phr respectively. Elongation at break decreases as increasing dose. Tear strength of rubber films was from 30-40 N/mm. The tackiness of latex films decreases and smell of vulcanized latex is almost negligible. (author)

  6. Radiation processing of liquid with low energy electron accelerator

    International Nuclear Information System (INIS)

    Makuuchi, Keizo

    2003-01-01

    Radiation induced emulsion polymerization, radiation vulcanization of NR latex (RVNRL) and radiation degradation of natural polymers were selected and reviewed as the radiation processing of liquid. The characteristic of high dose rate emulsion polymerization is the occurrence of cationic polymerization. Thus, it can be used for the production of new materials that cannot be obtained by radical polymerization. A potential application will be production of polymer emulsion that can be used as water-borne UV/EB curing resins. The technology of RVNRL by γ-ray has been commercialized. RVNRL with low energy electron accelerator is under development for further vulcanization cost reduction. Vessel type irradiator will be favorable for industrial application. Radiation degradation of polysaccharides is an emerging and promising area of radiation processing. However, strict cost comparison between liquid irradiation with low energy EB and state irradiation with γ-ray should be carried out. (author)

  7. Radiation processing of liquid with low energy electron accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2003-02-01

    Radiation induced emulsion polymerization, radiation vulcanization of NR latex (RVNRL) and radiation degradation of natural polymers were selected and reviewed as the radiation processing of liquid. The characteristic of high dose rate emulsion polymerization is the occurrence of cationic polymerization. Thus, it can be used for the production of new materials that cannot be obtained by radical polymerization. A potential application will be production of polymer emulsion that can be used as water-borne UV/EB curing resins. The technology of RVNRL by {gamma}-ray has been commercialized. RVNRL with low energy electron accelerator is under development for further vulcanization cost reduction. Vessel type irradiator will be favorable for industrial application. Radiation degradation of polysaccharides is an emerging and promising area of radiation processing. However, strict cost comparison between liquid irradiation with low energy EB and state irradiation with {gamma}-ray should be carried out. (author)

  8. Radiation processing in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-03-01

    Economic scale of radiation application in the field of industry, agriculture and medicine in Japan in 1997 was investigated to compare its economic impacts with that of nuclear energy industry. Total production value of radiation application accounted for 54% of nuclear industry including nuclear energy industry and radiation applications in three fields above. Industrial radiation applications were further divided into five groups, namely nondestructive test, RI instruments, radiation facilities, radiation processing and ion beam processing. More than 70% of the total production value was brought about by ion beam processing for use with IC and semiconductors. Future economic prospect of radiation processing of polymers, for example cross-linking, EB curing, graft polymerization and degradation, is reviewed. Particular attention was paid to radiation vulcanization of natural rubber latex and also to degradation of natural polymers. (S. Ohno)

  9. Radiation processing in Japan

    International Nuclear Information System (INIS)

    Makuuchi, Keizo

    2001-01-01

    Economic scale of radiation application in the field of industry, agriculture and medicine in Japan in 1997 was investigated to compare its economic impacts with that of nuclear energy industry. Total production value of radiation application accounted for 54% of nuclear industry including nuclear energy industry and radiation applications in three fields above. Industrial radiation applications were further divided into five groups, namely nondestructive test, RI instruments, radiation facilities, radiation processing and ion beam processing. More than 70% of the total production value was brought about by ion beam processing for use with IC and semiconductors. Future economic prospect of radiation processing of polymers, for example cross-linking, EB curing, graft polymerization and degradation, is reviewed. Particular attention was paid to radiation vulcanization of natural rubber latex and also to degradation of natural polymers. (S. Ohno)

  10. Radiation vulcanization of natural rubber latex (NRL) using low energy electron beam accelerator

    International Nuclear Information System (INIS)

    Feroza Akhtar; Keizo Makuuchi; Fumio Yoshii

    1996-01-01

    The electron beam induced vulcanization of natural rubber latex has been studied using low energy Electron Beam (EB) accelerators of 300, 250 and 175 keV ne latex was irradiated in a special type stainless steel reaction reactor with a stirrer at the bottom of the reactor. From the results it was found that 300 and 250 keV accelerators could effectively vulcanize NRL. But accelerator of 175 keV is too low energy to vulcanize the latex. At the same time a drum type irradiator where thin layer of NRL was irradiated by accelerator, was used for vulcanization of NRL. This type of irradiator also showed good physical properties of vulcanized latex. The effects of beam current and stirrer speed on vulcanization were studied

  11. Industrial application of electron beams for grafting and vulcanization

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1994-12-31

    The topics discussed are radiation graft polymerization; industrial application of radiation grafting - ion exchange membrane for a battery separator, ammonia adsorbent, non-flammable PE (polyethylene) foam; R and D on radiation grafting, radiation vulcanization of natural rubber.

  12. Industrial application of electron beams for grafting and vulcanization

    International Nuclear Information System (INIS)

    Keizo Makuuchi

    1994-01-01

    The topics discussed are radiation graft polymerization; industrial application of radiation grafting - ion exchange membrane for a battery separator, ammonia adsorbent, non-flammable PE (polyethylene) foam; R and D on radiation grafting, radiation vulcanization of natural rubber

  13. Extractable proteins from field radiation vulcanized natural rubber latex

    Energy Technology Data Exchange (ETDEWEB)

    Parra, Duclerc F. [Chemical and Environmental Centre, Nuclear Energy Research Institute, Av. Lineu Prestes, 2242-CEP Sao Paulo (Brazil)]. E-mail: dfparra@ipen.br; Pinto Martins, Carlos Felipe [Chemical and Environmental Centre, Nuclear Energy Research Institute, Av. Lineu Prestes, 2242-CEP Sao Paulo (Brazil); Collantes, Hugo D.C. [Chemical and Environmental Centre, Nuclear Energy Research Institute, Av. Lineu Prestes, 2242-CEP Sao Paulo (Brazil); Lugao, Ademar B. [Chemical and Environmental Centre, Nuclear Energy Research Institute, Av. Lineu Prestes, 2242-CEP Sao Paulo (Brazil)

    2005-07-01

    The type I allergy associated with the use of natural rubber latex (NRL) products is caused by the NRL proteins leached by the sweat or other body fluids. Makuuchi's group proposed for the first time the proteins removal by the addition of water-soluble polymers (WSP) on radiation vulcanization of natural rubber latex (RVNRL) that is a promising process under development in many countries. In this study, Brazilian field natural rubber was irradiated with a {sup 60}Co gamma source to reduce the content of WSP in the final product. WSP was used as additive to improve the extraction of protein. After irradiation the RVNRL was centrifuged to extract the WSP and proteins. The analytical methodology for protein content was based on the modified Lowry method according to ASTM D5712. Protein determination was carried out in serum of latex and in the extracts of the gloves. The concentration of extractable water-soluble proteins in serum of irradiated field NRL (NRL1), not irradiated one (NRL2); of twice centrifuged sample with polymer additive NRL (NRL3) and of the glove manufactured (NRLG) are compared with commercial glove (CG). The irradiation process increases the extractable water-soluble proteins, EP, as reported in the literature. In this study the use of polymeric additive on the bi-centrifugation process to remove protein was successful and the EP of the glove obtained in NRL3 was at around 40% of the commercial glove.

  14. Status of radiation processing in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Dela Rosa, A M [Philippine Nuclear Research Institute, Diliman, Quezon City (Philippines)

    2001-03-01

    Radiation processing, one of the well established applications of radiation and radioisotopes, has been successfully integrated into the industrial development of many countries worldwide. Environmental considerations embodied in the Montreal Protocol, the need for energy conservation brought about by escalating costs of fossil fuels, and the bright prospect of utilizing indigenous materials for value-added products have catalyzed the rapid development of radiation processing in the Asia region. This paper presents an overview of current developments in research activities and commercial applications of radiation processing in the Philippines. The areas of application include radiation sterilization of medical products, food irradiation, radiation vulcanization of natural rubber latex, radiation modification of the marine polysaccharide, carrageenan, and upgrading of cellulosic agriwaste by irradiation. (author)

  15. Status of radiation processing in the Philippines

    International Nuclear Information System (INIS)

    Dela Rosa, A.M.

    2001-01-01

    Radiation processing, one of the well established applications of radiation and radioisotopes, has been successfully integrated into the industrial development of many countries worldwide. Environmental considerations embodied in the Montreal Protocol, the need for energy conservation brought about by escalating costs of fossil fuels, and the bright prospect of utilizing indigenous materials for value-added products have catalyzed the rapid development of radiation processing in the Asia region. This paper presents an overview of current developments in research activities and commercial applications of radiation processing in the Philippines. The areas of application include radiation sterilization of medical products, food irradiation, radiation vulcanization of natural rubber latex, radiation modification of the marine polysaccharide, carrageenan, and upgrading of cellulosic agriwaste by irradiation. (author)

  16. Effect of Antioxidants on Radiation Vulcanization Natural Rubber Latex (RVNRL) Film

    International Nuclear Information System (INIS)

    Syuhada Ramli; Sofian Ibrahim; Muhammad Saiful Omar

    2015-01-01

    This paper presents the results on the effects of different antioxidants used in Radiation Vulcanization Natural Rubber Latex (RVNRL)) films between 0 to 10 weeks monitoring. Antioxidants used for the RVNRL formulation were Aquanox LP, Irganox and Wingstay L. Color difference evaluation by using Chroma Meter CR-400 found that RVNRL film with Irganox was the most stained yellowish after 8 weeks monitoring. Tensile strength for RVNRL with Aquanox found achieved the optimum strength between 25.4 to 27.13 mPa. The scanner electron microscopic (SEM) indicated more Aquanox molecules to penetrate and interact with the rubber molecule, thus becoming more effective inhibitor against its oxidative ageing. (author)

  17. ESR investigation of NR and IR rubber vulcanized with different cross-link agents

    Directory of Open Access Journals (Sweden)

    P. Posadas

    2016-01-01

    Full Text Available This study evaluates the formation of radical species in natural rubber (NR and poly-isoprene rubber (IR during the vulcanization process and the uniaxial deformation of the formed networks by means of Electron Spin Resonance (ESR. Vulcanization of NR and IR always shows a radical pathway, where the different vulcanization systems dictate the concentration of radical species in the course of this complex process. The greatest concentration of radicals were detected during the vulcanization with sulfur/accelerator based on efficient systems (EV, followed by conventional (CV and sulfur donor systems, whereas azide and organic peroxide agents showed smaller concentration of radicals. Independently of the vulcanization system, certain amount of radicals was detected on the vulcanized samples after the end of the vulcanization process. Comparison between different matrices demonstrates that NR always shows higher concentration of radicals than IR in the vulcanization process as well as during uniaxial deformation, fact that could be associated to the presence of nonrubber components in NR.

  18. Thermal stabilities of various rubber vulcanization cured by sulfur, peroxide and gamma radiation

    International Nuclear Information System (INIS)

    Basfar, A.A.; Shamshad Ahmed; Abdel Aziz, M.M.

    1999-01-01

    Sulfur and peroxide-cured rubber vulcanizates of NR and EPDM were obtained by blending the elastomers with fillers, antioxidants and appropriate accelerators, followed by vulcanization at 150 - 160 degree C. Blends of the same elastomers with appropriate co-agents and additives were also cured by gamma radiation at 150 and 200 kGy. A comparison of the thermal stabilities of these vulcanizates prepared by different curing techniques has been made by thermogravimetric analysis (TGA), assessed on the basis of comparison of DTG peak maxima, temperature for loss of 50% mass and actual thermal curves. The comparison reveals that the sulfur-cured vulcanizates are less thermally stable than their peroxide-cured counterparts. This may be attributed to the presence of a stronger C-C bond in case of peroxide-cured vulcanizates compared to weaker C-S sub x-C bond in case of sulfur-cured vulcanizates. However, compared to peroxide-cured vulcanizates, radiation-cured formulations demonstrated much improved thermal stability. This may originate from the existence of more uniformly distributed crosslinks and the enhanced rate of crosslink formation in the radiation process as compared to peroxide curing. In all the formulations whether sulfur, peroxide or radiation-cured, the natural rubber vulcanizates were found to be thermally much inferior to the synthetic contender, EPDM. Influence of variation of the amount of co-agent and other additives on the thermal stabilities of formulations of radiation cured NR and EPDM vulcanizates was also investigated

  19. Effect of heterogeneous distribution of crosslink density on physical properties of radiation vulcanized NR (Natural Rubber) latex film

    International Nuclear Information System (INIS)

    Keizo Makuuchi; Fumio Yoshii; Miura, H.; Murakami, K.

    1996-01-01

    Thus a study has been carried out to investigate the effect of particle to particle variation in crosslink density on physical properties of radiation vulcanized NR latex film. NR latex was irradiated in small bottle by γ rays without vulcanization accelerator to provide latex rubber particles having homogeneous distribution of crosslink density. The doses were 30, 50, 100, 250, 300, 400, 500 and 600 kGy. Weight swelling ratio, gel fraction, tensile strength and elongation at break of the latex film from the mixed latex were measured. The vulcanization dose of this latex was 250 kGy. Then the two different latexes were mixed in a such way to adjust the average dose of 250 kGy to prepare a latex consisting of rubber particles having heterogeneous distribution of crosslink density. Tensile strength of the latex film was depressed by mixing. The reduction increased with increasing the decrease of gel fraction by mixing. However the reduction was not serious when the dose difference of two latexes was less than 200 kGy

  20. Improvement of Some Physical Properties of Loaded Nitrile Rubber Vulcanized by Ionizing Radiation

    International Nuclear Information System (INIS)

    Abdel-Aziz, M.M.; Basfar, A.A.; Mofti, S.

    2000-01-01

    The effect of four-selected polyfunctional compounds namely, tri methylacrylic ester, trimethylol propane trimethacrylate, zinc diacrylate and modified pentaerthritol triacrylate, as crosslinking agents, on the mechanical properties of radiation vulcanized nitrile rubber was studied. The effect of incorporation of either HAF-carbon black or fumed silica, as filler and reinforcing agents, on its mechanical properties was also studied. The co agent namely, tri methylacrylic ester, was found to produce a set of optimum mechanical properties, i.e. moderate crosslink density, good tensile strength and elasticity at low irradiation doses, i.e.40 kGy

  1. Recent status and progress of radiation processing in the world

    International Nuclear Information System (INIS)

    Lee, Yun Jong; Lee, Byoung Hun; Im, Don Sun; Kim, Jae Ho; Nho, Young Chang

    2008-01-01

    Radiation technology is currently used in a number of industrial processes such as sterilization, cross linking of polymer, food irradiation, rubber vulcanization in the tire manufacturing, contaminated medical waste, etc. Gamma ray and electron beam are the key examples of well-established economical applications of radiation processes. The purpose of this paper is to review the recent technological trends and activities for radiation processes in order for the industrial end users to better understand, and obtain useful information about the technology. It is clear that the radiation processing technology has potential for a variety of the industrial applications

  2. Recent status and progress of radiation processing in the world

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yun Jong; Lee, Byoung Hun; Im, Don Sun; Kim, Jae Ho; Nho, Young Chang [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup(Korea, Republic of)

    2008-01-15

    Radiation technology is currently used in a number of industrial processes such as sterilization, cross linking of polymer, food irradiation, rubber vulcanization in the tire manufacturing, contaminated medical waste, etc. Gamma ray and electron beam are the key examples of well-established economical applications of radiation processes. The purpose of this paper is to review the recent technological trends and activities for radiation processes in order for the industrial end users to better understand, and obtain useful information about the technology. It is clear that the radiation processing technology has potential for a variety of the industrial applications.

  3. Surgical gloves fabrication using natural rubber latex vulcanized with gamma radiation

    International Nuclear Information System (INIS)

    Collantes, Hugo David Chirinos.

    1995-01-01

    Surgical gloves were manufactured by immersion coagulant method from vulcanized natural rubber latex by gamma rays at dose of 10 kGy in the air, at room temperature, using the following sensitizer vulcanization An-B 3 phr/KOH 0.2 phr. The influence of the parameter in the thickness of the surgical gloves manufacture, studied through fractional factorial designs technic, can be resumed by empirical linear correlation: y = 0.213 + 0.025 [Ca Cl 2 ] + 0.019 t. (author). 49 refs., 13 figs., 31 tabs

  4. Study on preparation of new antioxidants for radiation vulcanized natural rubber latex product. Antioxidant from keratin

    International Nuclear Information System (INIS)

    Nguyen Quoc Hien; Nguyen Van Toan; Vo Tan Thien; Le Hai

    2000-01-01

    The thermo-oxidative aging resistance of radiation vulcanization of natural rubber latex (RVNRL) products should be adequately by using suitable antioxidants or new kind of effective antioxidant. This work presents the results of preparation of natural antioxidant from hair keratin. Characteristics and effectiveness of resultant antioxidant are also presented. The results obtained indicates that antioxidant made from hair keratin is safe and effective for rubber products from RVNRL. (author)

  5. Thermal-kinetic study of natural rubber latex films vulcanized by using gamma radiation; Estudo termo-cinetico de filmes de latex de borracha natural de Hevea brasiliensis vulcanizada por radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Ana Paula Pinho Rodrigues; Barros, Glaucione Gomes de [Brasilia Univ., DF (Brazil). Inst. de Quimica; Guedes, Selma M.L. [Instituto de Pesquisa em Energia Nuclear, Sao Paulo, SP (Brazil)

    1999-07-01

    Vulcanization of natural rubber latex by ionization radiation produces the crosslink in disperse latex particles. Advantages over conventional process of vulcanization are: the absence of carcinogenic nitrosamines, low cytotoxicity and better degradation at room conditions, due to mainly to the absence of sulfur, zinc oxide and dithiocarbamates. Thermogravimetric analysis (TG) is the measurement of the weight change of a material as a function of temperature and time. TG data different heat speed provide an alternative model of the kinetics of degradation of polymeric materials. The kinetic studies of this material showed a single degradation process at least for 76,5% of mass loss. The activation energy was 49 Kcal/mol. For higher mass loss (85%) the degradation was characterized by associate mechanism. (author)

  6. Prospects for radiation processing in the Philippines

    International Nuclear Information System (INIS)

    Navarro, Q.O.

    1980-01-01

    A review of the status of current facilities and capabilities for radiation processing is presented together with industrial data from some selected industries. Due to limited accessibility of actual production/consumption data only tentative conclusions could be made regarding radiation technology applications for local industries. The order of priority, based on available information, appears to be medical sterilization, food irradiation, wood products modification, radiation polymerization, and rubber latex ''vulcanization.'' There is still a need for market survey and analyses, upgrading of radiation facilities, enactment of appropriate legislations, training of industrial technologies, and increased financial investment in order to make radiation technology a viable alternative to current local practices. (author)

  7. A study of using polythiol compounds and 2-ethyl-hexyl-acrylate with carbon tetrachloride as sensitizers for radiation vulcanization of natural rubber latex

    International Nuclear Information System (INIS)

    Polsuksiri, C.

    1989-01-01

    Experiments on using 3 different compounds of polythiol and an acrylate as sensitizer for radiation vulcanization were conducted. It was found that 1,4 butane diol propane tris-3-mercapto propionate showed the tendency to be a good sensitizer. The tensile strength of the rubber film prepared from the irradiated latex was found to be 14 MPa at sensitizer concentration of 1 phr and radiation dose of 45 kGy. As for 2-ethyl hexyl acrylate (2EHA), the maximum tensile strength of rubber film was found to be 23 MPa at concentration of 3 phr and radiation dose of 35 kGy. The mixture of 2 EHA and CCl 4 at various ratio was also used as sensitizer. The optimum ratio was found to be 5:1 at concentration of 6 phr and radiation dose of 15 kGy. The maximum tensile strength was as high as 25 MPa. The study also revealed that the radiation vulcanized latex with crosslink density of about 18x10 18 C.L./cm 3 would give the rubber film of highest tensile strength

  8. The effect of proteins on the aging properties of radiation vulcanized natural rubber latex

    International Nuclear Information System (INIS)

    Abad, L.V.

    1993-01-01

    The effect of natural rubber latex (NRL) proteins on the aging properties of NRL films was investigated. SDS-PAGE electrophoresis of the rubber proteins in NRL (Sri-Lanka) indicated a total of 18 proteins. A sharp decrease in tensile strength was observed after aging when NRL films were leached in 1% NH 4 OH. However, when these films were soaked in ethanol prior to leaching, the aging properties approximated those of the unleashed samples. Electrophoretic analysis of the proteins present in the NH 3 extracts of leached RVNRL films showed a high concentration of the protein herein. This protein was not found in the NH 3 extracts of ethanol soaked films. NRL proteins were shown to decelerate the aging process of Radiation Vulcanized Natural Rubber Latex (RVNRL) films. Among the proteins, herein exhibited good anti-aging properties. The hydrolyzates from NR proteins also enhanced considerably the aging properties of RVNRL. (auth.). 8 refs.; 40 figs.; 30 tabs

  9. Radiation vulcanization of rubbers

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2002-02-01

    An abstract of the radiation process of polymer materials and the polymer reaction by radiation is explained. Main radiation is 250 keV to 10 MeV of electron rays in the industry. Radiation cross-linked rubber has less the tensile strength than that by sulfur and organic peroxide crosslinking. The main origins of low tensile strength are caused by cut of backbone chain and ozone depend on radiation. Acceleration of crosslinking and short time of radiation are necessary to improve these defects. To accelerate crosslinking, we used crosslinking accelerators, for example, three poly-functional monomers (PFM). The maximum tensile strength of styrene-butadiene rubber (SBR) not added crosslinking accelerators showed 3 MPa at 110 kGy, but SBR added A-TMMT (tetramethylolmethane tetraacrylate) showed 5.5 MPa at 110 kGy. Radiation crosslinking of many kinds of rubber: isoprene (IR), SBR, CR, nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), butyl rubber (IIR), chlorinated butyl rubber (CIIR), EPM and TPE are explained. (S.Y.)

  10. Radiation vulcanization of rubbers

    International Nuclear Information System (INIS)

    Makuuchi, Keizo

    2002-01-01

    An abstract of the radiation process of polymer materials and the polymer reaction by radiation is explained. Main radiation is 250 keV to 10 MeV of electron rays in the industry. Radiation cross-linked rubber has less the tensile strength than that by sulfur and organic peroxide crosslinking. The main origins of low tensile strength are caused by cut of backbone chain and ozone depend on radiation. Acceleration of crosslinking and short time of radiation are necessary to improve these defects. To accelerate crosslinking, we used crosslinking accelerators, for example, three poly-functional monomers (PFM). The maximum tensile strength of styrene-butadiene rubber (SBR) not added crosslinking accelerators showed 3 MPa at 110 kGy, but SBR added A-TMMT (tetramethylolmethane tetraacrylate) showed 5.5 MPa at 110 kGy. Radiation crosslinking of many kinds of rubber: isoprene (IR), SBR, CR, nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), butyl rubber (IIR), chlorinated butyl rubber (CIIR), EPM and TPE are explained. (S.Y.)

  11. Mechanical Properties of Dynamically Vulcanized Thermoplastic Polyurethane (TPU/Polybutadiene Rubber (BR Blends

    Directory of Open Access Journals (Sweden)

    Ji-Hoo Kim

    2017-01-01

    Full Text Available To obtain thermoplastic polyurethane (TPU with low hardness, dynamically vulcanized TPU/polybutadiene rubber(BR(70/30 blends were prepared. The effect of dicumyl peroxide (DCP content and stabilizers on the tensile strength and elongation at break of the dynamically vulcanized blends was examined. The tensile strength and elongation at break of the dynamically vulcanized blends decrease with increasing content of DCP. The addition of optimal content of stabilizer leads to the improvement of tensile strength and elongation at break of the blends. Also, the effect of sulfur cure systems and accelerators on the tensile strength and elongation of the blends was investigated. The tensile strength and elongation at break of all the dynamically vulcanized TPU/BR (70/30 blends using 1-step processing are not higher than those of simple TPU/BR (70/30 blends. However, the tensile strength and elongation of the dynamically vulcanized blends prepared at 8 min (mixing time using 2-step processing are higher than those of the simple blends.

  12. RVNRL and radiation processing in Thailand

    International Nuclear Information System (INIS)

    Siri-Upathum, C.

    2000-01-01

    Industrial application of radiation processing in Thailand is gaining wide acceptance. The first private-owned radiation sterilization plant was established in 1984. Commercialization of protective rubber gloves from radiation vulcanized of natural rubber latex (RVNRL) started in 1993. Two new sterilization plants using electron beam accelerator and gamma irradiation were commissioned in 1997 and 1999 respectively. Another gamma sterilization plant is scheduled to operate in the year 2000. Additional electron accelerator is being installed in one operational gamma sterilization plant, for upgrading of gemstones. Research and development at Office of Atomic Energy for Peace (OAEP) and universities has been focused on RVNRL, radiation treatment of sludge, grafting of cassava starch and utilization of irradiated silk protein. Except for RVNRL which has passed to commercial scale, pilot scale of radiation treatment of sludge has achieved its goal to be utilized as new resources for animal feed and fertilizer. (author)

  13. RVNRL and radiation processing in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Siri-Upathum, C. [Department of Nuclear Technology, Faculty of Engineering, Chulalongkorn University, Bangkok (Thailand)

    2000-03-01

    Industrial application of radiation processing in Thailand is gaining wide acceptance. The first private-owned radiation sterilization plant was established in 1984. Commercialization of protective rubber gloves from radiation vulcanized of natural rubber latex (RVNRL) started in 1993. Two new sterilization plants using electron beam accelerator and gamma irradiation were commissioned in 1997 and 1999 respectively. Another gamma sterilization plant is scheduled to operate in the year 2000. Additional electron accelerator is being installed in one operational gamma sterilization plant, for upgrading of gemstones. Research and development at Office of Atomic Energy for Peace (OAEP) and universities has been focused on RVNRL, radiation treatment of sludge, grafting of cassava starch and utilization of irradiated silk protein. Except for RVNRL which has passed to commercial scale, pilot scale of radiation treatment of sludge has achieved its goal to be utilized as new resources for animal feed and fertilizer. (author)

  14. Thermal stability of radiation vulcanized EPDM rubber

    International Nuclear Information System (INIS)

    Abdel-Aziz, M.M.

    2005-01-01

    Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) have been used to study the thermal stability of gamma- ray vulcanized ethylene-propylene diene rubber (EPDM) stabilized with various types of antioxidants. The antioxidants used were penta erythrityl tetrakis(3,5- di-tert-butyl(-4-hydroxyphenyl)propionate (Irganox 1010), Irganox 1035, Irganox 1520 D, as primary antioxidants; Irganox B 561 and Irganox B 900, as synergistic blends; hindered amine light stabilizer (HALS), i.e. Tinuvin 622 LD; N-isopropyl-N-phenyl-p-phenylene diamine (IPPD) and Trimethyl quinoline (TMQ) and their mixtures. The measurements were carried out under atmospheric conditions. The effect of antioxidant type, selected concentration and mechanism of reaction were determined

  15. The Effect of Paraffin Wax to Properties of Radiation Vulcanization Natural Rubber Latex (RVNRL)

    International Nuclear Information System (INIS)

    Mohd Noorwadi Mat Lazim; Sofian Ibrahim; Muhammad Saiful Omar

    2015-01-01

    Dipping factories often encounter a serious problem with high tackiness of the finish products during storage. The tackiness effect can be lead to rejection of products. This tackiness effect of natural (NR) rubber film originates in the free rubber chain ends at the surface of the film. The tackiness is not depends on the degree of crosslinking (vulcanization), since radiation itself unable to reduce the tackiness effect. The RVNRL requires addition of additive or anti-tack agent into formulation to reduce tackiness effect. In this experiment, paraffin wax manufactured by Emulco Sdn Bhd under the trade name Aquawax 48 was added into RVNRL formulation as anti-tack and the effect of paraffin wax to physical and mechanical properties of RVNRL was study. (author)

  16. Radiation processing in India. Current status and future program

    International Nuclear Information System (INIS)

    Mittal, Jai Pal

    2003-01-01

    Radiation processing is an alternative to conventional methods such as thermal and chemical processing in many industrial applications. In India, this technology has found extensive applications in area of healthcare, agriculture, food preservation, industry and environment. Both gamma radiation and electron beam accelerators are being utilized for this purpose. Presently, 6 commercial gamma irradiators housing about 1.5 million curie Co-60 and an annual turnover of over US$ 2 million and 3 commercial electron beam (EB) accelerators with installed capacity of 185 kW are commercially operating in India. Five demonstration plants housing a total of 0.5 million curie Co-60 have been set up to assess the techno-commercial viability of the processes such as radiation vulcanization of natural rubber latex, decontamination of spices, hygienization of sewage sludge, shelf-life extension of onions. The new areas being explored include use of electron beam treated pulp for viscose-rayon process, radiation processed 'hydrogel' burn/wound dressings and radiation processing of natural polymers. In the present paper, the current status of this program, especially the recent developments and future direction of radiation processing technology in India is reviewed. (author)

  17. Progress in radiation processing of polymers

    Science.gov (United States)

    Chmielewski, Andrzej G.; Haji-Saeid, Mohammad; Ahmed, Shamshad

    2005-07-01

    Modification in polymeric structure of plastic material can be brought either by conventional chemical means or by exposure to ionization radiation from ether radioactive sources or highly accelerated electrons. The prominent drawbacks of chemical cross-linking typically involve the generation of noxious fumes and by products of peroxide degradation. Both the irradiation sources have their merits and limitations. Increased utilization of electron beams for modification and enhancement of polymer materials has been in particular witnessed over the past 40 years. The paper highlights several recent cases of EB utilization to improve key properties of selected plastic products. In paper is provided a survey of radiation processing methods of industrial interest, encompassing technologies which are already commercially well established, through developments in the active R&D stage which show pronounced promise for future commercial use. Radiation cross-linking technologies discussed include: application in cable and wire, application in rubber tyres, radiation vulcanization of rubber latex, development of radiation crosslinked SiC fiber, polymer recycling, development of gamma compatible pp, hydrogels etc. Over the years, remarkable advancement has been achieved in radiation processing of natural polymers. Role of radiation in improving the processing of temperature of PCL for use as biodegradable polymer, in accelerated breakdown of cellulose into viscose and enhancement in yields of chitin/chitosan from sea-food waste, is described.

  18. Progress in radiation processing of polymers

    Energy Technology Data Exchange (ETDEWEB)

    Chmielewski, Andrzej G. [International Atomic Energy Agency, Industrial Applications and Chemistry Section, Division of Physical and Chemical Sciences, Department of Nuclear Sciences and Applications, Wagramer Street 5, Vienna 1400 (Austria) and Department of Process and Chemical Engineering, Warsaw University of Technology, Warsaw (Poland)]. E-mail: a-g.chmielewski@iaea.org; Haji-Saeid, Mohammad [International Atomic Energy Agency, Industrial Applications and Chemistry Section, Division of Physical and Chemical Sciences, Department of Nuclear Sciences and Applications, Wagramer Street 5, Vienna 1400 (Austria); Ahmed, Shamshad [Applied Chemistry Laboratories, Pakistan Institute of Nuclear Science and Technology, P.O. Box Nilore, Islamabad (Pakistan)

    2005-07-01

    Modification in polymeric structure of plastic material can be brought either by conventional chemical means or by exposure to ionization radiation from ether radioactive sources or highly accelerated electrons. The prominent drawbacks of chemical cross-linking typically involve the generation of noxious fumes and by products of peroxide degradation. Both the irradiation sources have their merits and limitations. Increased utilization of electron beams for modification and enhancement of polymer materials has been in particular witnessed over the past 40 years. The paper highlights several recent cases of EB utilization to improve key properties of selected plastic products. In paper is provided a survey of radiation processing methods of industrial interest, encompassing technologies which are already commercially well established, through developments in the active R and D stage which show pronounced promise for future commercial use. Radiation cross-linking technologies discussed include: application in cable and wire, application in rubber tyres, radiation vulcanization of rubber latex, development of radiation crosslinked SiC fiber, polymer recycling, development of gamma compatible pp, hydrogels etc. Over the years, remarkable advancement has been achieved in radiation processing of natural polymers. Role of radiation in improving the processing of temperature of PCL for use as biodegradable polymer, in accelerated breakdown of cellulose into viscose and enhancement in yields of chitin/chitosan from sea-food waste, is described.

  19. Progress in radiation processing of polymers

    International Nuclear Information System (INIS)

    Chmielewski, Andrzej G.; Haji-Saeid, Mohammad; Ahmed, Shamshad

    2005-01-01

    Modification in polymeric structure of plastic material can be brought either by conventional chemical means or by exposure to ionization radiation from ether radioactive sources or highly accelerated electrons. The prominent drawbacks of chemical cross-linking typically involve the generation of noxious fumes and by products of peroxide degradation. Both the irradiation sources have their merits and limitations. Increased utilization of electron beams for modification and enhancement of polymer materials has been in particular witnessed over the past 40 years. The paper highlights several recent cases of EB utilization to improve key properties of selected plastic products. In paper is provided a survey of radiation processing methods of industrial interest, encompassing technologies which are already commercially well established, through developments in the active R and D stage which show pronounced promise for future commercial use. Radiation cross-linking technologies discussed include: application in cable and wire, application in rubber tyres, radiation vulcanization of rubber latex, development of radiation crosslinked SiC fiber, polymer recycling, development of gamma compatible pp, hydrogels etc. Over the years, remarkable advancement has been achieved in radiation processing of natural polymers. Role of radiation in improving the processing of temperature of PCL for use as biodegradable polymer, in accelerated breakdown of cellulose into viscose and enhancement in yields of chitin/chitosan from sea-food waste, is described

  20. Vulcanization Kinetics of Natural Rubber Based On Free Sulfur Determination

    Directory of Open Access Journals (Sweden)

    Abu Hasan

    2013-05-01

    Full Text Available The determination of free sulfur in the rubber vulcanizates provided significant representation of vulcanization reaction. In this research, the effects of vulcanization temperature, the mixing method of carbon black into rubber, the ingredients mixing sequence and the type of carbon black were studied on masticated and milled natural rubber in which the reaction was observed by un-reacted sulfur determination. The results showed that higher vulcanization temperature provided faster vulcanization reaction and greater reaction rate constant. Similarly, the mixing sequence of ingredient and carbon black into rubber influenced the rate of vulcanization reaction. The subsequent ingredients mixing sequence, in this case, resulted in higher vulcanization rate compared to that of the simultaneous one. However, the mixing method of carbon black into rubber brought small effect on the rate of vulcanization reaction. The type of carbon black applied was observed to influence the reaction rate of vulcanization. Smaller particle sizes of carbon black gave larger reaction rate constant. In this case, the type of carbon black N 330 gave faster vulcanization rate than that of N 660.

  1. Thermo-chemical de-vulcanization of suphur-vulcanized SBR assisted by de-vulcanization aids and oxidation stabilizers

    NARCIS (Netherlands)

    Saiwari, Sitisaiyidah; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.

    2013-01-01

    Ground tire rubber (GTR) from whole passenger car tires is composed of several types of rubbers and fillers, making de-vulcanization of this material rather complicated. The most critical component in this material is SBR, as it tends to degrade and recombine during the commonly used reclaiming

  2. The Vulcan Advanced Hybrid Manufacturing System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Made In Space is developing the The Vulcan Advanced Hybrid Manufacturing System (VULCAN) to address NASA's requirement to produce high-strength, high-precision...

  3. The Use of Ionizing Radiation in the Vulcanization of Silicon Rubber; Utilisation des radiations ionisantes pour la vulcanisation du caoutchouc au silicone; Ispol'zovanie ioniziruyushchikh izluchenij dlya vulkanizatsii silikonovogo kauchuka; Empleo de las radiaciones ionizantes en la vulcanizacion del caucho de siliconas

    Energy Technology Data Exchange (ETDEWEB)

    Kuzminsky, A S; Nikitina, T S; Oksentevich, L A [Rubber Research Institute, Moscow, Union of Soviet Socialist Republics (Russian Federation)

    1960-07-15

    Main purpose of the work - a detailed study of the properties of materials obtained by irradiating mixtures of polydimethylsiloxan e rubber and various fillers (special silicic acid, titanium dioxide, flue dust, chimney soot and lamp black). The irradiation was done with a powerful X-ray unit and a Co{sup 60} gamma-ray source of 20,000 gr. radium equivalent. The relative speed of formation of the space lattice of the vulcanized material was evaluated (by the size of the equilibrium constant and the maximum degree of swelling in benzene). Changes in tensile strength and specific elongation during the irradiation process were studied. The optimum vulcanization regime was chosen and the basic physico-mechanical characteristics of the vulcanized materials were defined. Changes in the properties of the irradiated vulcanized material during hot aging at temperatures of 150{sup o}, 200{sup o} and 250{sup o} were studied. Irradiation in vulcanization removes the necessity for carrying out the process at high temperatures and for keeping the product under controlled temperature conditions for long periods after vulcanization. This new method of vulcanizing allows the use of carbon black as a filler. The use of ionizing radiation makes it possible to simplify the technique of vulcanizing silicon rubber and to improve the properties of the vulcanized material. (author) [French] L'etude porte avant tout sur les proprietes des matieres qu'on obtient apres avoir expose a des radiations du caoutchouc au polydimethyl-siloxane melange a des produits d'addition differents (acide silicique special, bioxyde de titane, noir de fumee en poudre impalpable obtenu au four et a la lampe). L'exposition aux radiations s'effectuait dans une installation puissante de rayons X et avec une source de rayonnement gamma en {sup 60}Co avec une activite de 20 000 g. eq. ra. Les auteurs ont evalue la vitesse relative de formation du reseau spatial des vulcanisants (selon la grandeur du module d

  4. Automobile parts by radiation crosslinking

    International Nuclear Information System (INIS)

    Yoshii, Fumio

    2008-01-01

    Radiation crosslinking, graft polymerization and degradation are useful technologies to improve polymer materials. The crosslinking causes improvement in strength, heat stability and processability to gives network structure for polymer materials and hence crosslinked materials are used in various fields, especially car parts. Electron beam (EB) of short time irradiation is used for these modifications. Irradiated (pre-vulcanized) before sulfur vulcanization rubber tires, heat resistant wires/cables, shrinkable tubes and foams of car parts are achieved by EB crosslinking. Polyethylene and polyvinyl chloride are used in cables and wires, polypropylene in plastic foams and natural rubber etc. In this paper radiation processing of tire, wire/cables, foams, shrinkable tubes and circuit protection devices (CPT) are explained. (author)

  5. Production of medical supplies from elastomers vulcanized with ionizing radiation; Obtencao de artefatos medicos a partir de elastomeros vulcanizados com radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Guedes, Selma M.L.; Collantes, Hugo David Chirinos; Kodama, Yasko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1996-07-01

    The silicon was vulcanized by gamma rays in the absence of organic peroxides. The natural rubber latex was vulcanized by gamma rays and electron beams in the absence and presence of sensitizer. The surgical gloves fabricated with latex containing nB-A vulcanized by gamma rays can be commercialized. Another expected applications are the development of the catheter and the material utilized in the radiotherapy treatment. (author)

  6. Effect of vulcanization temperature and humidity on the properties of RTV silicone rubber

    Science.gov (United States)

    Wu, Xutao; Li, Xiuguang; Hao, Lu; Wen, Xishan; Lan, Lei; Yuan, Xiaoqing; Zhang, Qingping

    2017-06-01

    In order to study the difference in performance of room temperature vulcanized (RTV) silicone rubber in vulcanization environment with different temperature and humidity, static contact angle method, FTIR and TG is utilized to depict the properties of hydrophobicity, transfer of hydrophobicity, functional groups and thermal stability of RTV silicone rubber. It is found that different vulcanization conditions have effects on the characteristics of RTV silicone rubber, which shows that the hydrophobicity of RTV silicone rubber changes little with the vulcanization temperature but a slight increase with the vulcanization humidity. Temperature and humidity have obvious effects on the hydrophobicity transfer ability of RTV silicone rubber, which is better when vulcanization temperature is 5°C or vulcanization humidity is 95%. From the Fourier transform infrared spectroscopy, it can be concluded that humidity and temperature of vulcanization conditions have great effect on the functional groups of silicone rubber, and vulcanization conditions also have effect on thermal stability of RTV silicone rubber. When vulcanization temperature is 5°C or vulcanization humidity is 15% or 95%, the thermal stability of silicone rubber becomes worse.

  7. Production Of Hollow Toy Product From Radiation Pre vulcanized Natural Rubber Latex (RVNRL) By Using Casting And Moulding Technique

    International Nuclear Information System (INIS)

    Mohd Noorwadi Mat Lazim; Sofian Ibrahim; Muhammad Saiful Omar

    2013-01-01

    Hollow toy products are very synonym to the child from the age of months since it able to stimulating each of their sense such as sight, hearing, taste, touch and smell. Most of hollow toy products are made from natural rubber latex by using moulding and casting technique. The moulding and casting technique is a manufacturing process by pored liquid latex into a mould, which contain cavity of the desired shape. The mould made from plaster of Paris able to absorbs water from latex meanwhile the presence of calcium ions from plaster of Paris will tend to diffuse into latex thus promote formation of deposit on surface of cavity mould. To improve the quality and safety of hollow toy product made from latex, Radiation Pre vulcanized Natural Rubber Latex (RVNRL) has been identified to be used because it can fulfill the standard requirement for latex and also due to its special abilities such as lower modulus (soft latex products), nitrosamines free, low in nitrosatables, free from chemical accelerators induced allergies and better biodegradability. This paper identify the problem appears from the process of making hollow toy products from RVNRL by using moulding and casting technique. (author)

  8. The role of proteins on the thermal oxidative aging of radiation vulcanized natural rubber latex

    International Nuclear Information System (INIS)

    Abad, L.V.; Rosa, A. de la; Keizo Makuuchi; Fumio Yoshii

    1996-01-01

    The effect of Hevea latex proteins on the aging properties of radiation vulcanized natural rubber latex (RVNRL) was investigated. Unpurified RVNRL films exhibited better aging properties than the purified RVNRL films. A sharp decrease in tensile strength was observed after aging when RVNRL films were leached in 1% NH sub 4 OH. However, when these films were soaked in ethanol prior to leaching, the aging properties approximated those of the unleached samples. Kjeldahl and FT-IR analyses of the leached and unleached RVNRL films indicated a higher protein content for both the unleached and ethanol-soaked films than for leached films. Electrophoretic analysis of the proteins present in the NH, extracts of leached RVNRL films showed a high concentration of hevein. This protein was not found in the ATH, extracts of ethanol soaked films. Hevein was shown to improve the aging properties of RVNRL

  9. Radiation modification of materials

    International Nuclear Information System (INIS)

    Pikaev, A.K.

    1987-01-01

    Industrial and radiation chemical processes of material modification based on cross-linking of polymers as a result of radiation are considered. Among them are production of cables and rods with irradiated modified insulation, production of hardened and thermo-shrinkaging polymer products (films, tubes, fashioned products), production of radiation cross-linked polyethylene foam, technology of radiation vulcanization of elastomers. Attention is paid to radiation plants on the basis of γ-sources and electron acceleratos as well as to radiation conditions

  10. Studied on Virgin Coconut Oil (VCO) and Olive Oil (OO) as an Alternative for Stabilizer of Radiation Vulcanized Natural Rubber Latex (RVNRL) Preparation

    International Nuclear Information System (INIS)

    Syuhada Ramli; Sofian Ibrahim; Mohd Noorwadi Mat Lazim

    2016-01-01

    This paper presents the effects of virgin coconut oil (VCO) and olive oil (OO) as an alternative stabilizer in the radiation vulcanized natural rubber latex (RVNRL). Potassium laurite (KL) as a stabilizer considered as a control of RVNRL sample were compared to mixed ratio 1:1 KL: VCO and 1:1 KL: OO stabilizer formulation. Total solid content (TSC) and tensile strength (TS) results showed no significant different between the formulations. Mechanical stability time (MST) indicates higher stability of RVNRL with addition of VCO. The fatty acid composition in VCO indicate VCO was acting well as stabilizer for latex stabilizer formulation. (author)

  11. Gamma irradiation degradation/modification of 5-ethylidene 2-norbornene (ENB)-based ethylene propylene diene rubber (EPDM) depending on ENB content of EPDM and type/content of peroxides used in vulcanization

    Energy Technology Data Exchange (ETDEWEB)

    Ozdemir, Tonguc [Department of Polymer Science and Technology, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: tonguc.ozdemir@tr.net

    2008-06-15

    In this study, the radiation degradation/modification of the vulcanized EPDM and the effects of dose rate, peroxide type/content in vulcanization system and ENB content of EPDM were studied to investigate the change in the extend of the modification/degradation of the mechanical properties of vulcanized EPDM via gamma irradiation. In addition, thermal, dynamic mechanical, ATR-FTIR, TGA, TGA-FTIR tests were carried out to understand the change of properties of vulcanized EPDM via irradiation. Samples were irradiated with two different dose rates of 1280 and 64.6 Gy/h. Total dose of irradiation was up to 184 kGy. The FTIR spectral analysis showed structural changes of EPDM via irradiation. It was observed that the dose rate changed the mechanical properties with different extends. The change of ENB content of EPDM and peroxide type and content in vulcanization system affect extend of the modification/degradation of the EPDM's properties.

  12. Influence of zinc oxide during different stages of sulfur vulcanization. Elucidated by model compound studies

    NARCIS (Netherlands)

    Heideman, G.; Datta, Rabin; Noordermeer, Jacobus W.M.; van Baarle, B.

    2005-01-01

    The addition of zinc oxide (ZnO) as an activator for the sulfur vulcanization of rubbers enhances the vulcanization efficiency and vulcanizate properties and reduces the vulcanization time. The first part of this article deals with the reduction and optimization of the amount of ZnO. Two different

  13. Evaluation of some antioxidants in radiation vulcanized ethylene-propylene diene (EPDM) rubber

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Aziz, M.M.; Basfar, A.A. E-mail: abasfar@kacst.edu.sa

    2001-12-01

    Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) have been used to study the oxidation of {gamma}-ray vulcanized ethylene-propylene diene rubber (EPDM) stabilized with various types of antioxidants. The antioxidants used were pentaerythrityl tetrakis(3,5-di-tert-butyl(-4-hydroxyphenyl))propionate (Irganox 1010), Irganox 1035, Irganox 1520D, as primary antioxidants; Irganox B561 and Irganox B900, as synergistic blends; hindered amine light stabilizer (HALS), i.e. Tinuvin 622 LD; N-isopropyl-N-phenyl-p-phenylene diamine (IPPD) and trimethyl quinoline (TMQ) and their mixtures. The measurements were carried out under atmospheric conditions. The effects of antioxidant type and its selected concentration were determined and mechanism of reaction proposed.

  14. VULCAN: An Open-source, Validated Chemical Kinetics Python Code for Exoplanetary Atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Shang-Min; Grosheintz, Luc; Kitzmann, Daniel; Heng, Kevin [University of Bern, Center for Space and Habitability, Sidlerstrasse 5, CH-3012, Bern (Switzerland); Lyons, James R. [Arizona State University, School of Earth and Space Exploration, Bateman Physical Sciences, Tempe, AZ 85287-1404 (United States); Rimmer, Paul B., E-mail: shang-min.tsai@space.unibe.ch, E-mail: kevin.heng@csh.unibe.ch, E-mail: jimlyons@asu.edu [University of St. Andrews, School of Physics and Astronomy, St. Andrews, KY16 9SS (United Kingdom)

    2017-02-01

    We present an open-source and validated chemical kinetics code for studying hot exoplanetary atmospheres, which we name VULCAN. It is constructed for gaseous chemistry from 500 to 2500 K, using a reduced C–H–O chemical network with about 300 reactions. It uses eddy diffusion to mimic atmospheric dynamics and excludes photochemistry. We have provided a full description of the rate coefficients and thermodynamic data used. We validate VULCAN by reproducing chemical equilibrium and by comparing its output versus the disequilibrium-chemistry calculations of Moses et al. and Rimmer and Helling. It reproduces the models of HD 189733b and HD 209458b by Moses et al., which employ a network with nearly 1600 reactions. We also use VULCAN to examine the theoretical trends produced when the temperature–pressure profile and carbon-to-oxygen ratio are varied. Assisted by a sensitivity test designed to identify the key reactions responsible for producing a specific molecule, we revisit the quenching approximation and find that it is accurate for methane but breaks down for acetylene, because the disequilibrium abundance of acetylene is not directly determined by transport-induced quenching, but is rather indirectly controlled by the disequilibrium abundance of methane. Therefore we suggest that the quenching approximation should be used with caution and must always be checked against a chemical kinetics calculation. A one-dimensional model atmosphere with 100 layers, computed using VULCAN, typically takes several minutes to complete. VULCAN is part of the Exoclimes Simulation Platform (ESP; exoclime.net) and publicly available at https://github.com/exoclime/VULCAN.

  15. On The compatibility and dynamic vulcanization of Pom/Nbr blends

    International Nuclear Information System (INIS)

    Mortezaee, M.; Naveed Family, M.H.; Mehrabzadeh, M.

    2001-01-01

    Polymer blends based on polyacetal butadiene rubber were prepared by melt blending technique. The mixing parameters such ad temperature, time and speed of mixing were varied to obtain a wide range of properties. The mixing parameters were optimized by evaluating the mechanical properties of the blend over a wide range of mixing conditions. The morphology of the blend indicated a two-phase structure. This study describes an attempt to improve the tensile strength of Pom/Nbr blends by means of compatibility and dynamic vulcanization. A commercial compatibility, maleic anhydride (Ma), has been used to control the phase morphology of the blend system. Dicumyl peroxide is used to dynamically vulcanize the Nbr elastomer in the blend. The tensile strength of the compatibility systems showed improvement. Dynamic vulcanization raises elastic recovery and tensile modulus of the blends, but the elongation at break decreases

  16. A novel thermoplastic elastomer based on dynamically vulcanized polypropylene/acrylic rubber blends

    Directory of Open Access Journals (Sweden)

    2008-08-01

    Full Text Available Thermoplastic elastomer based on polypropylene (PP and acrylic rubber (ACM was investigated, with special attention on the compatibilization and dynamic vulcanization. ACM component contains chlorine and carboxyl groups along the backbone, which act as center for the curing and reactive compatibilization. The last event was carried out by adding a combination of maleic anhydride-modified PP (PP-g-MA and triethylene tetramine (TETA, which act as interfacial agents between PP and ACM phases. The effectiveness of the compatibilization was suggested from mixing torque and viscosity, determined from rheological measurements. Outstanding mechanical performance, especially elongation at break, and better tensile set (lower values were obtained with the compatibilization. The dynamic vulcanization also resulted in good mechanical properties for compatibilized blends, but the performance was inferior to that observed for non vulcanized blends. The effect of the compatibilization and/or dynamic vulcanization on the dynamic mechanical, thermal, morphological and stress relaxation properties was investigated.

  17. Pathway for high-quality reclaim by thermal treatment of sulfur-vulcanized SBR

    NARCIS (Netherlands)

    Saiwari, Sitisaiyidah; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.

    2011-01-01

    De-vulcanization of SBR (Styrene Butadiene Rubber) is a challenge, as the broken polymer chains tend to re-arrange. This influences the properties of the reclaimed and re-vulcanized rubber, and reduces the quality of the recycled material. Within this study, the breakdown of sulfur-cured SBR in a

  18. Improvement of Physico-Chemical Properties of Recycled (Elastomers /Thermoplastics) Composites using Ionizing Radiation

    International Nuclear Information System (INIS)

    Ibrahim, M.Y.E.A.

    2013-01-01

    Recycling of ground tire rubber (GRT) not only solves the waste disposal problem and maintains environmental quality, but also saves the valuable and limited resource of fossil feedstock. The major problem in the recycling of rubber-like materials such as tires is the cross linked molecular structure of already vulcanized rubber, which not only prevents the softening and processing of waste rubber particles but also inhibits binding of the powder surface to the virgin material. Several reclamation methods have proposed to overcome these barriers, which have basically followed two main approaches: (1) the de vulcanization of cured rubber and (2) the surface modifications of waste particles. The de vulcanization of rubber causes the cleavage of crosslinks via chemical treatments, which make used rubber suitable to be reformulated and recurred into new articles. In consequence, this work is mainly aimed to prepare of de vulcanized rubber (DR) and evaluating mechanical, thermal, and morphological properties of the thermoplastic vulcanizations (TPVs) based on de vulcanized rubber blended with polypropylene, EPDM using peroxide under the effect of radiation dose and DR feed ratio. The efficiency of the compounding process has been examined by infrared spectroscopy (FTIR), X-ray diffraction and scanning electron microscopy (SEM). The mechanical and thermal behaviors of the blends composed of de vulcanized rubber (DR) , high crystalline polypropylene (PP) and EPDM in different proportions were studied. Evaluation of the mechanical and thermal properties of the developed blends, unirradiated and gamma irradiated, was carried out using tensile strength (Ts), elongation at break (Eb), hardness, TGA and DSC measurements.

  19. The Vulcan pulse generating system

    International Nuclear Information System (INIS)

    Danson, C.N.; Edwards, C.B.; Wyatt, R.W.W.

    1985-01-01

    During the past two years several changes have been made to the front end system on the VULCAN pulse generating system. These changes give greater flexibility and a wider choice of operating conditions. This note gives an updated description of the system capabilities, and gives users of the facility an idea of the various pulse combinations that are available. (author)

  20. Effect of phenol formaldehyde resin as vulcanizing agent on flow behavior of HDPE/PB blend

    Directory of Open Access Journals (Sweden)

    Moayad N. Khalaf

    2014-07-01

    Full Text Available Thermoplastic elastomer (TPE based on High density polyethylene (HDPE/polybutadiene (HDPE/PB = 70/30 parts blends containing 1, 3, 5, 7 and 10 wt.% of dimethylol phenolic resin as a vulcanizing agent in the presence of SnCl2 as catalyst was prepared. The dimethylol phenolic resin was prepared in our laboratory. The blends were compounded in mixer-60 attached to a Haake rheochord meter-90. The rheological properties were measured at temperatures 140, 160, 180 and 200 °C. The linearity of the flow curve appeared for 5% of the vulcanizing agent. The shear stress and shear viscosity have increased upon increasing the shear rate over a range of loading levels of vulcanizing agent of 1%, 3%, 5%, 7% and 10%. This may be attributed to the increased vulcanization between polyethylene and the rubber blend. The flow behavior index of the system shows a pseudo plastic nature behavior (since n < 1. The consistency index (K increased with the increase in the phenol formaldehyde resin content and the temperature. Hence, the increase in the value of the consistency index (K of the polymer melts refers to more viscous materials prepared. The activation energy for the TPE blends fluctuated indicating that there is phase separation; where each polymer behaved separately. This study showed that HDPE/PB blends are characterized with good rheological properties, which can be recommended to be processed with the injection molding technique.

  1. The Effect of Novel Binary Accelerator System on Properties of Vulcanized Natural Rubber

    Directory of Open Access Journals (Sweden)

    Moez Kamoun

    2009-01-01

    Full Text Available The mechanical properties, curing characteristics, and swelling behaviour of vulcanized natural rubber with a novel binary accelerator system are investigated. Results indicate that the mechanical properties were improved. Crosslinking density of vulcanized natural rubber was measured by equilibrium swelling method. As a result, the new binary accelerator was found to be able to improve both cure rate and crosslinking density. Using the numerical analysis of test interaction between binary accelerator and operational modelling of vulcanization-factors experiments, it can be concluded that the interaction (Cystine, N-cyclohexyl-2-benzothiazyl sulfenamide was significant and the optimum value of binary accelerator was suggested, respectively, at levels 0 and +1.

  2. Zinc chelates as new activators for sulphur vulcanization of acrylonitrile-butadiene elastomer

    Directory of Open Access Journals (Sweden)

    2009-04-01

    Full Text Available The goal of this work was to apply several zinc chelates as activators for sulphur vulcanization of acrylonitrilebutadiene elastomer (NBR, in order to find alternatives for the conventionally used zinc oxide. In this article, we discuss the effects of different zinc complexes on the cure characteristics, crosslinks distribution in the elastomer network and mechanical properties of acrylonitrile-butadiene rubber. Zinc chelates seem to be good substitutes for zinc oxide as activators for sulphur vulcanization of NBR rubber, without detrimental effects on the crosslinking process and physical properties of the obtained vulcanizates. Moreover, application of zinc complexes allows to reduce the amount of zinc ions in rubber compounds by 40% compared to conventionally crosslinked vulcanizates with zinc oxide. It is a very important ecological goal since zinc oxide is classified as toxic to aquatic species and its amount in rubber products must be reduced below 2.5% at least. From a technological point of view it is a very important challenge.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-08-01

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

  4. Feasibility study on utilization of vitrified radioactive waste as radiation sources

    International Nuclear Information System (INIS)

    Makuuchi, Keizo; Yoshii, Fumio; Hyakutake, Kenichiro

    1995-01-01

    A feasibility study on utilization of vitrified high level radioactive waste (VW) as radiation source has been carried out. Natural rubber latex was radiation vulcanized with VW to demonstrate the feasibility. The dose rate was 0.1 kGy/hr. As a sensitizer, n-butyl acrylate was added. Negligible small activation of natural rubber (NR) latex by neutron from the VW was observed. The residual sensitizer in the irradiated latex and physical properties of film molded from the irradiated latex were the same level with the conventional radiation vulcanization of NR latex with γ-rays from Co-60. Surgical gloves and protective rubber gloves for radioactive contamination were produced from 20 litters of NR latex vulcanized with 2 VWs. The physical properties of both gloves were acceptable. These results suggested that vitrified high level waste can be used as an industrial radiation source. (author)

  5. Radiation response of Philippine natural rubber latex

    International Nuclear Information System (INIS)

    Dela Rosa, A.M.; Abad, L.V.; Ana-Relleve, L.S.; Tranquilan-Aranilla, C.; Pascual, C.L.

    1998-01-01

    Our earlier work has shown that the natural rubber latex (NRL) produced and processed in the Philippines is suited for radiation vulcanization. The cast films from NRL with 50% TSC exhibited maximum tensile strengths of 25-32 MPa at 15 kGy, which is the vulcanization dose or Dv. In the manufacture of dipped NRL products, certain specifications such as %TSC, protein content and tensile properties, must be met to ensure an acceptable product. For radiation vulcanization of natural rubber latex (RVNRL) to be accepted as an alternative process, it must also meet the requirements. Thus, this paper presents additional data on the radiation response of local NRL at different total solids contents (TSC), leachable proteins from NRL films as a function of dose, and the thermal activities of irradiated natural rubber latex (INRL). Different formulations of NRL showed varying tolerances to nBA. Data showed that as %TSC increases, the maximum concentration of nBA that can be added without affecting the stability of the latex decreases. The Dv increases as the %TSC increases and the nBA content decreases. This difference in response may be attributed to a lower concentration of nBA in formulations with higher %TSC. These data indicate that the parameters in the radiation treatment will be dictated by the intended applications of INRL. The thermogravimetric data showed greater stability of INRL to thermal oxidation relative to the unirradiated NRL, which correlates directly with the tensile properties of the INRL. A radiation dose of 10 kGy increased the amount of proteins leached from cast latex films. The amount of extractable proteins did not increase significantly at higher doses. The SDS PAGE analysis of the extractable proteins from unirradiated latex film showed distinct bands. An additional band at 60 Kda appeared at 10 kGy. All these bands became diffuse at higher doses, indicating the radiolysis of the proteins

  6. Environmental Exposure and Accelerated Testing of Rubber-to-Metal Vulcanized Bonded Assemblies

    Science.gov (United States)

    1974-11-01

    btadiene/acrylonitrile ( NBR ) rubber -to-metat -. canized bonded assemblies at the two exposure sites are shown in Table 5. After exposure for one year...AD-A0-17 368 EN~VIRONMENTAL EXPOSURE AND ACCELERATED TESTING OF RUBBER -TO-METAL VULCANIZED BONDED ASSEMBLIES John A. WilliamsI Rock Island Arseital...COMMERCE 325116 1AD R-TR-75-013 ENViRONMENTAL EXPOSURE AND ACCELERATED TESTING OF RUBBER -TO-METAL VULCANIZED BONDED ASSEMBLIES by __ John A. Williams

  7. Radiation processing of natural polymers using low energy electron beam

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    2004-01-01

    Radiation processing is widely used in Japan and the economic scale of radiation application amounted to about 71 b$ (ratio relative to GDP: 1.7%) in total. It consisted of 60 b$ (85%) in industry, 10 b$ (14%) in medicine and 1 b$ (1%) in agriculture. Irradiation using gamma-ray from 60 Co and electron beam is commercially used for the sterilization and modification of materials. Utilization of natural polymers by radiation has been investigated for recycling the natural resources and reducing the environmental pollution. Polysaccharides such as chitosan, sodium alginate, carrageenan, cellulose, pectin were easily degraded by irradiation and induced various kinds of biological activities, i.e. anti-bacterial activity, elicitor activity, plant growth promotion, suppression of environmental stress on plants. Radiation degraded chitosan was effective to enhance the growth of plants in tissue culture. Low energy electron beam (EB) irradiation has a variety of applications and good safety. A self-shielded low energy electron accelerator system needs an initial investment much lower than a 60 Co facility. It was demonstrated that the liquid sample irradiation system using low energy EB was effective not only for the preparation of degraded polysaccharides but also for radiation vulcanization of natural rubber latex (RVNRL). Some carbohydrate derivatives, carboxymethylcellulose (CMC), carboxymethyl-starch and carboxymethyl-chitin/chitosan, can be crosslinked under certain radiation condition and produced the biodegradable hydrogel for medical and agricultural use. Treatment of soybean seeds by low energy EB enhanced the growth and the number of rhizobia on the root. (author)

  8. Vulcanization of polybutadiene latex induced by 60Co γ-rays irradiation

    International Nuclear Information System (INIS)

    Liu Yuguang; Huang Yudong; Hou Jing; Gao Deyu; Zhang Xuequan

    2007-01-01

    Fully vulcanized polybutadiene rubber particles (FVBR) were prepared by polybutadiene latex (PBL) vulcanization induced by 60 Co γ-rays irradiation, and the effect of absorbed dose on crosslinking behavior was studied. Mean diameter, diameter distribution and morphology of the particles in the PBL irradiated at different doses as well as in the FVBR were characterized by laser particle analyzer and AFM. The crosslinking effect on the mechanical properties of the films, by casting from PBL at different doses correspondingly, was evaluated by mechanical and dynamic mechanical analysis (DMA) respectively. The results showed that the diameter and swelling property decreased with absorbed dose, while crosslink density and gel fraction increased. Moreover, the decrease of the tensile strength and elongation at break, the increase of the hardness in shore A and young's modulus (E), and the increase of storage modulus (E') and narrowing of loss tangent peak (Tan 8) were all accounted for the increment of crosslinking. The Charlesby-Pinner equation fits well with the PBL vulcanization in the range of absorbed doses from 0 to 200kGy. (authors)

  9. Extraction and comparison of proteins from natural rubber latex by conventional and ionizing radiation methods

    International Nuclear Information System (INIS)

    Rogero, Sizue O.; Spencer, Patrick J.; Campos, Vania E.; Lusvarghi, Fabio M.; Higa, Olga Z.

    1997-01-01

    Several proteins in natural rubber latex (NRL) have been assigned to be significant allergens. It is known that proteins submitted to ionizing radiation suffer denaturation and immunochemical modification resulting in low antigenic reactivity. The aim of this study was to extract and compare water extractable proteins from NRL films vulcanized by conventional and by ionizing radiation methods. SDS-polyacrylamide gel electrophoresis (SDS--PAGE) and high pressure liquid chromatography (HPLC) showed a diffuse protein band of about 14 KDa, which we believe is rubber elongation factor (REF), in both eluates, but smaller in latex film vulcanized by ionizing radiation. REF has been suggested to be a major latex allergen. These data suggest that ionizing radiation vulcanization could be an useful method for the production of NRL goods with low antigenicity. (author). 8 refs., 2 figs., 1 tab

  10. MATERIAL PARAMETER OF RUBBER GLOVE VULCANIZED USING COMBINED INFRARED AND HOT-AIR HEATING

    OpenAIRE

    Tipapon Khamdaeng; Numpon Panyoyai; Thanasit Wongsiriamnuay

    2014-01-01

    Vulcanization is an important chemical-thermal process in production of rubber products resulting in change of material properties, increased elasticity and strength. In general, Young’s modulus is used as an indicator of elastic deformation at loading configuration. However, rubber is not truly elastic and a single parameter is insufficient to describe the whole deformation contributed by microstructure of rubber network. Therefore, we present the material parameters concerning the mec...

  11. The Effect of Gamma Irradiation on the Mechanical Properties of vulcanized Natural Rubber and Natural Rubber-Polyethylene Blends

    International Nuclear Information System (INIS)

    Sudradjat Iskandar

    2008-01-01

    To enhance the quality of vulcanized natural rubber and natural rubber-polyethylene blends, gamma irradiation has been done. The compound of natural rubber and natural rubber-polyethylene blends made by using roll mill machine. The mixed materials were antioxidant, anti ozon, plasticizer and vulcanisator. The natural rubber and natural rubber-polyethylene blends compound were vulcanizer and made a slab (film of sample) using hot and could press machine. The slabs produced were then gamma irradiated at irradiation dose of 75, 150 and 300 kGy. Before and after irradiation, the slab were characterized using strograph R1 machine. The results showed that the modulus 300 and hardness of vulcanized natural rubber and natural rubber-polyethylene blends were increasing; the tensile strength and tear strength were increasing to maximum level then decreasing with gamma irradiation, while the elongation at break was decreasing. The maximum tensile strength of vulcanized natural rubber and natural rubber-polyethylene blends were found at irradiation dose of 75 kGy. At the irradiation dose of 75 kGy, the tensile strength of vulcanized natural rubber increased from 17.6 MN/m 2 to 21.2 MN/m 2 , while the tensile strength of vulcanized natural rubber-polyethylene blends increased slightly from 18.7 MN/m 2 to 19.4 MN/m 2 . (author)

  12. Effect of radiation-induced modification in fluoroelastomer

    International Nuclear Information System (INIS)

    Zen, Heloisa Augusto; Lugao, Ademar Benevolo

    2013-01-01

    Polymers exposed to ionizing irradiation, even at low doses, often undergo structural changes accompanied by molecular crosslinking and chain scission (degradation) reactions. The general effect of the radiation on polymers is determined by the ratio of crosslinking to chain scission events. This ratio depends on parameters such as chemical structure, physical state, radicals stability and mobility, irradiation rate and irradiation atmosphere. The radiation process is a large used technique to promote modification in their structures to apply them in different areas and is well known for its merits and potential in modifying the chemical and the physical properties of polymeric materials without cause drastic changes in their inherent properties, depend on the dose irradiated. In this study was used fluoroelastomer with 70% - fluor that having excellent thermal, chemical and mechanical properties. Vulcanized and non-vulcanized samples of this material were submitted to gamma radiation under air atmosphere in order to observe the effect of atmosphere in the polymer matrix. The irradiated doses were 5, 10 and 20kGy, at room temperature. The characterization was made by scanning electron microscope (SEM), infrared spectroscopy using attenuate reflectance (ATR-IR) and X-ray diffraction. The results demonstrated which was expected, the degradation reactions were observed. (author)

  13. Hevea brasiliensis natural rubber latex film vulcanization by gamma radiation containing n-butyl acrylate: properties and morphology; Filme de latex de borracha natural de Hevea brasiliensis vulcanizado por radiacao gama contendo acrilato de n-butila: propriedades e morfologia

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Ana Paula Pinho; Barros, Glaucione Gomes de [Brasilia Univ., DF (Brazil). Dept. de Quimica; Guedes, Selma M.L. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1997-07-01

    Radiation vulcanization of natural rubber latex (RVNRL) in the presence of n-butyl acrylate (n-Ba) as sensitizer was carried out. The RVNRL films were investigated with respect to their thermal properties and morphology. The films presented two T{sub g} values obtained by DSC which were identified as due to linear and crosslinked domains. The thermal stability of the material was similar to that of linear material rubber. The morphology showed smooth regular surface characteristic of homogeneous phase domains. (author)

  14. Vulcanization Kinetics and Mechanical Properties of Ethylene Propylene Diene Monomer Thermal Insulation

    Directory of Open Access Journals (Sweden)

    Mohamad Irfan Fathurrohman

    2015-07-01

    Full Text Available The vulcanization kinetics of Ethylene-propylene diene monomer (EPDM rubber thermal insulation was studied by using rheometer under isothermal condition at different temperatures. The rheometry analysis was used to determining the cure kinetic parameters and predicting the cure time of EPDM thermal insulation. The experimental results revealed that the curing curves of EPDM thermal insulation were marching and the optimum curing time decreased with increasing the temperature. The kinetic parameters were determined from the autocatalytic model showed close fitting with the experimental results, indicating suitability of autocatalytic model in characterizing the cure kinetics. The activation energy was determined from the autocatalytic model is 46.3661 kJ mol-1. The cure time were predicted from autocatalytic model and the obtained kinetic parameter by using the relationship among degree of conversion, cure temperature, and cure time. The predictions of cure time provide information for the actual curing characteristic of EPDM thermal insulation. The mechanical properties of EPDM thermal insulation with different vulcanization temperatures showed the same hardness, tensile strength and modulus at 300%, except at temperature 70 °C, while the elongation at breaking point decreased with increasing temperature of vulcanization. © 2015 BCREC UNDIP. All rights reservedReceived: 8th April 2014; Revised: 7th January 2015; Accepted: 16th January 2015How to Cite: Fathurrohman, M.I., Maspanger, D.R., Sutrisno, S. (2015. Vulcanization Kinetics and Mechanical Properties of Ethylene Propylene Diene Monomer Thermal Insulation. Bulletin of Chemi-cal Reaction Engineering & Catalysis, 10 (2, 104-110. (doi:10.9767/bcrec.10.2.6682.104-110Permalink/DOI: http://dx.doi.org/10.9767/bcrec.10.2.6682.104-110 

  15. Preparation of the vulcan XC-72R-supported Pt nanoparticles for the hydrogen evolution reaction in PEM water electrolysers

    International Nuclear Information System (INIS)

    Nguyen, Huy Du; Nguyen, T Thuy Luyen; Nguyen, Khac Manh; Ha, Thuc Huy; Nguyen, Quoc Hien

    2015-01-01

    Pt nanoparticles on vulcan XC-72R support (Pt/vulcan XC-72R) were prepared by the impregnation–reduction method. The Pt content, the morphological properties and the electrochemical catalysis of the Pt/vulcan XC 72R materials have been investigated by ICP-OES analysis, FESEM, TEM, and cyclic voltammetry. These materials were then used as catalyst for hydrogen evolution reaction at the cathode of proton exchange membrane (PEM) water electrolysers. The best catalyst was Pt/vulcan XC-72R prepared by the impregnation–reduction method which is conducted in two reducing steps with the reductants of sodium borohydride and ethylene glycol, respectively. The current density of PEM water electrolysers reached 1.0 A cm"−"2 when applying a voltage of 2.0 V at 25 °C. (paper)

  16. Vulcanization characteristics and dynamic mechanical behavior of natural rubber reinforced with silane modified silica.

    Science.gov (United States)

    Chonkaew, Wunpen; Minghvanish, Withawat; Kungliean, Ulchulee; Rochanawipart, Nutthaya; Brostow, Witold

    2011-03-01

    Two silane coupling agents were used for hydrolysis-condensation reaction modification of nanosilica surfaces. The surface characteristics were analyzed using Fourier transform infrared spectroscopy (FTIR). The vulcanization kinetics of natural rubber (NR) + silica composites was studied and compared to behavior of the neat NR using differential scanning calorimetry (DSC) in the dynamic scan mode. Dynamic mechanical analysis (DMA) was performed to evaluate the effects of the surface modification. Activation energy E(a) values for the reaction are obtained. The presence of silica, modified or otherwise, inhibits the vulcanization reaction of NR. The neat silica containing system has the lowest cure rate index and the highest activation energy for the vulcanization reaction. The coupling agent with longer chains causes more swelling and moves the glass transition temperature T(g) downwards. Below the glass transition region, silica causes a lowering of the dynamic storage modulus G', a result of hindering the cure reaction. Above the glass transition, silica-again modified or otherwise-provides the expected reinforcement effect.

  17. ODC-Free Solvent Implementation Issues for Vulcanized Rubber and Bond Systems

    Science.gov (United States)

    Hodgson, James R.; McCool, Alex (Technical Monitor)

    2001-01-01

    Thiokol Propulsion has worked extensively to replace 1,1,1-trichloroethane (TCA) with ozone depleting chemicals (ODC)-free solvents for use in the manufacture of the Reusable Solid Rocket Motor (RSRM) for the Space Shuttle Program. As Thiokol has transitioned from sub-scale to full-scale testing and implementation of these new solvents, issues have been discovered which have required special attention. The original intent of Thiokol's solvent replacement strategy was to replace TCA with a single drop-in solvent for all equivalent applications. We have learned that a single candidate does not exist for replacing TCA. Solvent incompatibility with process materials has caused us to seek for niche solvents and/or processing changes that provide an ODC-free solution for special applications. This paper addresses some of the solvent incompatibilities, which have lead to processes changes and possible niche solvent usage. These incompatibilities were discovered during full-scale testing of ODC-free solvents and relate to vulcanized rubber and bond systems in the RSRM. Specifically, the following items are presented: (1) Cure effects of d-limonene based solvents on Silica Filled Ethylene Propylene Diene Monomer (SF-EPDM) rubber. During full-scale test operations, Thiokol discovered that d-limonene (terpene) based solvents inhibit the cure of EPDM rubber. Subsequent testing showed the same issue with Nitrile Butadiene Rubber (NBR). Also discussed are efforts to minimize uncured rubber exposure to solvents; and (2) Cured bond system sensitivity to ODC-free solvents. During full scale testing it was discovered that a natural rubber to steel vulcanized bond could degrade after prolonged exposure to ODC-free solvents. Follow on testing showed that low vapor pressure and residence time seemed to be most likely cause for failure.

  18. Study on grafting of monomer onto natural rubber latex by radiation technique

    International Nuclear Information System (INIS)

    Nguyen Tan Man; Le Hai; Tran Thi Tam; Le Huu Tu, Pham Thi Sam; Dao Minh Phuong; Ha Thuc Huy

    2004-01-01

    Radiation vulcanization of natural rubber latex has been extensively developed through programmers assisted by the IAEA and UNDP under RCA in Asia and Pacific Region. R-D has been done in most of the Member States with technical assistance from Japan's Takasaki Radiation Chemistry Establishment. Radiation vulcanized natural rubber latex (RVNRL) has many advantages over the conventional sulfur vulcanized latex, such as absence of nitrosamine and low cytotoxicity. Radiation crosslinking is a room temperature process, itself an important cost advantage, it is easily controlled and desired extend of crosslinking is easily achieved by controlling the dose (irradiation time). Disadvantages of RVNRL to be improved are poor physical properties of film such as low tensile strength and tear strength. The research groups of Japan, Thailand and Indonesia concentrated on the improvement of physical properties of RVNRL using radiation grafted PMMA as additive [2]. F. Sundardi and W. Sofiarti have reported that tensile strength and hardness increased by radiation grafting of styrene onto NR [5]. Ono et al have reported the grafting of MMA onto NR by gamma irradiation at a dose of 5 kGy for producing thermoplastic elastomers [4]. The objective of this project is to report the results of studies of radiation graft-copolymerization of methyl methacrylate (MMA) or styrene (St) onto natural rubber latex in order to improve their physico-mechanical properties and evaluation of grafted material using Small-Angle Neutron Scattering through FNCA Project. The grafting degree of MMA and St onto NR increased with the increase of irradiation dose and monomer concentration. The alteration of grafted products structure was determined by IR method. Tensile strength, Shore A hardness, 100% modulus of grafted products increased with the increase of monomer concentration and irradiation dose while elongation at break decreased. The grafted products were characterized by Transmission Electron

  19. Design of Self-Healing Supramolecular Rubbers by Introducing Ionic Cross-Links into Natural Rubber via a Controlled Vulcanization.

    Science.gov (United States)

    Xu, Chuanhui; Cao, Liming; Lin, Baofeng; Liang, Xingquan; Chen, Yukun

    2016-07-13

    Introducing ionic associations is one of the most effective approaches to realize a self-healing behavior for rubbers. However, most of commercial rubbers are nonpolar rubbers without now available functional groups to be converted into ionic groups. In this paper, our strategy was based on a controlled peroxide-induced vulcanization to generate massive ionic cross-links via polymerization of zinc dimethacrylate (ZDMA) in natural rubber (NR) and exploited it as a potential self-healable material. We controlled vulcanization process to retard the formation of covalent cross-link network, and successfully generated a reversible supramolecular network mainly constructed by ionic cross-links. Without the restriction of covalent cross-linkings, the NR chains in ionic supramolecular network had good flexibility and mobility. The nature that the ionic cross-links was easily reconstructed and rearranged facilitating the self-healing behavior, thereby enabling a fully cut sample to rejoin and retain to its original properties after a suitable self-healing process at ambient temperature. This study thus demonstrates a feasible approach to impart an ionic association induced self-healing function to commercial rubbers without ionic functional groups.

  20. Degrading radiation effects on properties of bromobutyl rubber compounds

    Energy Technology Data Exchange (ETDEWEB)

    Scagliusi, Sandra R.; Cardoso, Elisabeth C.L.; Pozenato, Cristina A.; Lugao, Ademar B., E-mail: srscagliusi@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The understanding of chemistry involved in degradation induced radiation is becoming more and more relevant in the re-use of polymeric materials, as well in beneficial radiation uses. Degrading radiation effects have been considered from viewpoint of controlled degradation for isoprene/isobutene in rubbers for recycling purposes. Bromobutyl rubber (BIIR) is an isobutylene/isoprene copolymer comprising 1.9 to 2.1% bromine and has a lot of applications including in tires air-chambers. In this work there were evaluated gamma-irradiation effects for re-use or recycling objectives in elastomeric bromobutyl compositions irradiated at 5, 15, 25, 50, 100,150 and 200 kGy. Mechanical properties, hardness and swelling were assessed in non-vulcanized and vulcanized rubber, non-irradiated and irradiated at different doses. The major gamma radiation effect in butyl rubber is the generation of free radicals along changes in mechanical properties. Irradiation effects in bromobutyl rubber compounds were comprehensively investigated, demonstrated and discussed. (author)

  1. Degrading radiation effects on properties of bromobutyl rubber compounds

    International Nuclear Information System (INIS)

    Scagliusi, Sandra R.; Cardoso, Elisabeth C.L.; Pozenato, Cristina A.; Lugao, Ademar B.

    2013-01-01

    The understanding of chemistry involved in degradation induced radiation is becoming more and more relevant in the re-use of polymeric materials, as well in beneficial radiation uses. Degrading radiation effects have been considered from viewpoint of controlled degradation for isoprene/isobutene in rubbers for recycling purposes. Bromobutyl rubber (BIIR) is an isobutylene/isoprene copolymer comprising 1.9 to 2.1% bromine and has a lot of applications including in tires air-chambers. In this work there were evaluated gamma-irradiation effects for re-use or recycling objectives in elastomeric bromobutyl compositions irradiated at 5, 15, 25, 50, 100,150 and 200 kGy. Mechanical properties, hardness and swelling were assessed in non-vulcanized and vulcanized rubber, non-irradiated and irradiated at different doses. The major gamma radiation effect in butyl rubber is the generation of free radicals along changes in mechanical properties. Irradiation effects in bromobutyl rubber compounds were comprehensively investigated, demonstrated and discussed. (author)

  2. Efeito de um resíduo do processo de galvanoplastia sobre a vulcanização da borracha natural (NR Effect from the waste from the electroplating process on the natural rubber (NR vulcanization

    Directory of Open Access Journals (Sweden)

    Alex C. S. Santos

    2009-01-01

    Full Text Available Um resíduo gerado no processo de galvanoplastia (RG, rico em metais, foi incorporado em composições de borracha natural (NR em substituição parcial ou total ao ativador comum do processo de vulcanização, o óxido de zinco (ZnO. As diferentes misturas foram preparadas em um misturador de calandras e, após a reometria, foram vulcanizadas a 150 °C. As propriedades mecânicas de resistência à tração e rasgo foram determinadas, além do teor de gel. Além disso, o efeito do resíduo RG sobre a cinética de vulcanização foi analisado através do modelo de Coran, usando-se as temperaturas de 150, 160 e 170 °C. Os resultados mostraram que RG desenvolve algum efeito catalítico sobre a vulcanização de NR, embora exista uma considerável perda na resistência à tração quando o teor de RG excede o do ZnO nas composições. Quanto ao rasgo, a propriedade é mantida em um patamar satisfatório enquanto teores menores de RG são utilizados.A waste generated in the electroplating process (RG, rich in metals, was incorporated in natural rubber (NR compositions, as a partial or complete replacement of zinc oxide (ZnO, which is a typical activator of the vulcanization process. Different mixtures were prepared in a two-roll mixer, which were vulcanized at 150 ºC after the rheometry measurements. Mechanical properties such as tensile and tear strength were evaluated, as well as the gel content. In addition, the effect of RG waste upon the vulcanization kinetics was analyzed with the Coran model using temperatures at 150, 160 and 170 ºC. The results showed that RG develops some catalytic effect upon NR vulcanization, but there is a poor mechanical performance when RG loading is higher than that of ZnO in the compositions. For the tear strength, the property is maintained at a reasonable level if a small RG loading is utilized.

  3. Electron linear accelerator system for natural rubber vulcanization

    Science.gov (United States)

    Rimjaem, S.; Kongmon, E.; Rhodes, M. W.; Saisut, J.; Thongbai, C.

    2017-09-01

    Development of an electron accelerator system, beam diagnostic instruments, an irradiation apparatus and electron beam processing methodology for natural rubber vulcanization is underway at the Plasma and Beam Physics Research Facility, Chiang Mai University, Thailand. The project is carried out with the aims to improve the qualities of natural rubber products. The system consists of a DC thermionic electron gun, 5-cell standing-wave radio-frequency (RF) linear accelerator (linac) with side-coupling cavities and an electron beam irradiation apparatus. This system is used to produce electron beams with an adjustable energy between 0.5 and 4 MeV and a pulse current of 10-100 mA at a pulse repetition rate of 20-400 Hz. An average absorbed dose between 160 and 640 Gy is expected to be archived for 4 MeV electron beam when the accelerator is operated at 400 Hz. The research activities focus firstly on assembling of the accelerator system, study on accelerator properties and electron beam dynamic simulations. The resonant frequency of the RF linac in π/2 operating mode is 2996.82 MHz for the operating temperature of 35 °C. The beam dynamic simulations were conducted by using the code ASTRA. Simulation results suggest that electron beams with an average energy of 4.002 MeV can be obtained when the linac accelerating gradient is 41.7 MV/m. The rms transverse beam size and normalized rms transverse emittance at the linac exit are 0.91 mm and 10.48 π mm·mrad, respectively. This information can then be used as the input data for Monte Carlo simulations to estimate the electron beam penetration depth and dose distribution in the natural rubber latex. The study results from this research will be used to define optimal conditions for natural rubber vulcanization with different electron beam energies and doses. This is very useful for development of future practical industrial accelerator units.

  4. Radiation measurements and quality control

    International Nuclear Information System (INIS)

    McLaughlin, W.L.

    1977-01-01

    Accurate measurements are essential to research leading to a successful radiation process and to the commissioning of the process and the facility. On the other hand, once the process is in production, the importance to quality control of measuring radiation quantities (i.e., absorbed dose, dose rate, dose distribution) rather than various other parameters of the process (i.e. conveyor speed, dwell time, radiation field characteristics, product dimensions) is not clearly established. When the safety of the product is determined by the magnitude of the administered dose, as in radiation sterilization, waste control, or food preservation, accuracy and precision of the measurement of the effective dose are vital. Since physical dose measurements are usually simpler, more reliable and reproducible than biological testing of the product, there is a trend toward using standardized dosimetry for quality control of some processes. In many industrial products, however, such as vulcanized rubber, textiles, plastics, coatings, films, wire and cable, the effective dose can be controlled satisfactorily by controlling process variables or by product testing itself. In the measurement of radiation dose profiles by dosimetry, it is necessary to have suitable dose meter calibrations, to account for sources of error and imprecision, and to use correct statistical procedures in specifying dwell times or conveyor speeds and source and product parameters to achieve minimum and maximum doses within specifications. (author)

  5. VULCAN PLANETS: INSIDE-OUT FORMATION OF THE INNERMOST SUPER-EARTHS

    Energy Technology Data Exchange (ETDEWEB)

    Chatterjee, Sourav [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Tan, Jonathan C., E-mail: sourav.chatterjee@northwestern.edu, E-mail: jt@astro.ufl.edu [Departments of Astronomy and Physics, University of Florida, Gainesville, FL 32611 (United States)

    2015-01-10

    The compact multi-transiting systems discovered by Kepler challenge traditional planet formation theories. These fall into two broad classes: (1) formation further out followed by migration and (2) formation in situ from a disk of gas and planetesimals. In the former, an abundance of resonant chains is expected, which the Kepler data do not support. In the latter, required disk mass surface densities may be too high. A recently proposed mechanism hypothesizes that planets form in situ at the pressure trap associated with the dead-zone inner boundary (DZIB) where radially drifting ''pebbles'' accumulate. This scenario predicts planet masses (M{sub p} ) are set by the gap-opening process that then leads to DZIB retreat, followed by sequential, inside-out planet formation (IOPF). For typical disk accretion rates, IOPF predictions for M{sub p} , M{sub p} versus orbital radius r, and planet-planet separations are consistent with observed systems. Here we investigate the IOPF prediction for how the masses, M{sub p,} {sub 1}, of the innermost (''Vulcan'') planets vary with r. We show that for fiducial parameters, M {sub p,} {sub 1} ≅ 5.0(r/0.1 AU) M {sub ⊕}, independent of the disk's accretion rate at time of planet formation. Then, using Monte Carlo sampling of a population of these innermost planets, we test this predicted scaling against observed planet properties, allowing for intrinsic dispersions in planetary densities and Kepler's observational biases. These effects lead to a slightly shallower relation M{sub p,} {sub 1}∝r {sup 0.9} {sup ±} {sup 0.2}, which is consistent with M{sub p,} 1∝r {sup 0.7} {sup ±} {sup 0.2} of the observed Vulcans. The normalization of the relation constrains the gap-opening process, favoring relatively low viscosities in the inner dead zone.

  6. Evolution of the radiation processing industry

    Science.gov (United States)

    Cleland, Marshall R.

    2013-04-01

    Early investigations of the effects of treating materials with ionizing radiations began in 1894 with the irradiation of gases at atmospheric pressure using cathode rays from a Crookes gas-discharge tube, in 1895 with the discovery of X-rays emitted from a Crookes tube, and in 1896 with the discovery of radioactivity in uranium. In 1897, small electrically charged particles were detected and identified in the gas discharges inside Crookes tubes. These particles were then named electrons. During the next three decades, it was found that these novel forms of energy could produce ions to initiate chemical reactions in some gases and liquids. By 1921, it had also been shown that insects, parasites and bacteria could be killed by treatment with ionizing radiation. In 1925, a high-vacuum tube with a thermionic cathode and a thin metallic anode was developed to produce electron beams in air by using accelerating potentials up to 250 kilovolts. That unique apparatus was the precursor of the many types of electron accelerators that have been developed since then for a variety of industrial applications. In 1929, the vulcanization of natural rubber without using any chemical additives was achieved by irradiation with electrons from a 250 kilovolt accelerator. In 1939, several liquid monomers were polymerized by treatment with gamma rays from radioactive nuclides. These early results were not exploited before the end of World War II because intense sources of ionizing radiation were not available then. Shortly after that war, there was increased interest in developing the peaceful uses of atomic energy, which included the chemical and biological effects of radiation exposures. Many uses that have been developed since then are described briefly in this paper. These industrial applications are now producing billions of US dollars in revenue every year.

  7. Evolution of the radiation processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Cleland, Marshall R. [IBA Industrial, Inc., 151 Heartland Boulevard, Edgewood, NY 11717 (United States)

    2013-04-19

    Early investigations of the effects of treating materials with ionizing radiations began in 1894 with the irradiation of gases at atmospheric pressure using cathode rays from a Crookes gas-discharge tube, in 1895 with the discovery of X-rays emitted from a Crookes tube, and in 1896 with the discovery of radioactivity in uranium. In 1897, small electrically charged particles were detected and identified in the gas discharges inside Crookes tubes. These particles were then named electrons. During the next three decades, it was found that these novel forms of energy could produce ions to initiate chemical reactions in some gases and liquids. By 1921, it had also been shown that insects, parasites and bacteria could be killed by treatment with ionizing radiation. In 1925, a high-vacuum tube with a thermionic cathode and a thin metallic anode was developed to produce electron beams in air by using accelerating potentials up to 250 kilovolts. That unique apparatus was the precursor of the many types of electron accelerators that have been developed since then for a variety of industrial applications. In 1929, the vulcanization of natural rubber without using any chemical additives was achieved by irradiation with electrons from a 250 kilovolt accelerator. In 1939, several liquid monomers were polymerized by treatment with gamma rays from radioactive nuclides. These early results were not exploited before the end of World War II because intense sources of ionizing radiation were not available then. Shortly after that war, there was increased interest in developing the peaceful uses of atomic energy, which included the chemical and biological effects of radiation exposures. Many uses that have been developed since then are described briefly in this paper. These industrial applications are now producing billions of US dollars in revenue every year.

  8. Radiation pre-vulcanization effect on properties of the truck tyre's transition layer and the truck tyre

    International Nuclear Information System (INIS)

    Yang Mingcheng; Zhu Jun; Li Kunhao; Guo Dongquan; Zhang Hongna; Zhang Benshang; Li Zhaopeng

    2013-01-01

    In this paper, the natural rubber is chosen as the main constituents for the transition layer of all-steel load radial tyre, which is pre-vulcanized by 500-keV E-beam irradiation of up to 60 kGy. The results show that the green strength of transitional layer increases with the dose, reaching four times as much as the control (without irradiation) at 60 kGy. The final mechanical properties do not differ significantly from those of the control except that the aging and fatigue performance increased. However, thickness of the natural rubber transitional layer for an average single tyre can be reduced by 1 mm (or 1.5 kg) without obvious adverse effect on tyre performance. (authors)

  9. Effects of composition and processing conditions on morphology and properties of thermoplastic elastomer blends of SEBS-PP-Oil and dynamically vulcanized EPDM-PP-Oil

    NARCIS (Netherlands)

    Sengupta, P.; Noordermeer, Jacobus W.M.

    2004-01-01

    This work presents a comparative study of the morphology and structure-related properties of thermoplastic elastomer blends based on SEBS-PP-oil and dynamically vulcanized EPDM-PP-oil prepared under identical conditions. Compositions of each blend type with three different SEBS-PP and EPDM-PP ratios

  10. Surface modification of halloysite nanotubes by vulcanization accelerator and properties of styrene-butadiene rubber nanocomposites with modified halloysite nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Bangchao; Jia, Zhixin, E-mail: zxjia@scut.edu.cn; Hu, Dechao; Luo, Yuanfang; Guo, Baochun; Jia, Demin

    2016-03-15

    Graphical abstract: - Highlights: • Vulcanization accelerant was used to modify halloysite nanotubes (HNTs). • The modified HNTs reduced the activation energy of vulcanization. • Strong filler–rubber interaction was achieved in rubber/modified HNTs composites. • The modified HNTs exhibited excellent reinforcement effect on rubber. - Abstract: Vulcanization accelerant N-cyclohexyl-2-benzothiazole sulfenamide (CZ) was used as a surface modifier and chemically grafted on the surface of halloysite nanotubes (HNTs) to obtain CZ-functionalized HNTs (HNTs-s-CZ). It was found that HNTs-s-CZ could be homogeneously dispersed into styrene-butadiene rubber (SBR). The grafted CZ molecules, exactly located at the filler-rubber interface, reduced the activation energy of vulcanization of SBR/HNTs-s-CZ compounds. Besides, the density of chain segments introduced by the interfacial phase of SBR/HNTs-s-CZ nanocomposites was higher than the other nanocomposites with silane-modified HNTs (m-HNTs) or pristine HNTs, manifesting an indication of enhanced filler-rubber interfacial interaction in SBR/HNTs-s-CZ nanocomposites. Consequently, SBR/HNTs-s-CZ nanocomposites showed excellent mechanical properties. The tensile strength could be enhanced by as much as 38.6% and 102.5% compared to those of SBR/m-HNTs and SBR/HNTs nanocomposites, respectively, though containing equivalent accelerant component. The value of this work lies in the fact that apparent properties improvement of elastomer composites has been achieved by the incorporation of vulcanization accelerant-functionalized HNTs, which may be fruitful for the rational design of filler surface treatment and offer new scientific and technological opportunities for the preparation of high performance elastomer composites.

  11. Surface modification of halloysite nanotubes by vulcanization accelerator and properties of styrene-butadiene rubber nanocomposites with modified halloysite nanotubes

    International Nuclear Information System (INIS)

    Zhong, Bangchao; Jia, Zhixin; Hu, Dechao; Luo, Yuanfang; Guo, Baochun; Jia, Demin

    2016-01-01

    Graphical abstract: - Highlights: • Vulcanization accelerant was used to modify halloysite nanotubes (HNTs). • The modified HNTs reduced the activation energy of vulcanization. • Strong filler–rubber interaction was achieved in rubber/modified HNTs composites. • The modified HNTs exhibited excellent reinforcement effect on rubber. - Abstract: Vulcanization accelerant N-cyclohexyl-2-benzothiazole sulfenamide (CZ) was used as a surface modifier and chemically grafted on the surface of halloysite nanotubes (HNTs) to obtain CZ-functionalized HNTs (HNTs-s-CZ). It was found that HNTs-s-CZ could be homogeneously dispersed into styrene-butadiene rubber (SBR). The grafted CZ molecules, exactly located at the filler-rubber interface, reduced the activation energy of vulcanization of SBR/HNTs-s-CZ compounds. Besides, the density of chain segments introduced by the interfacial phase of SBR/HNTs-s-CZ nanocomposites was higher than the other nanocomposites with silane-modified HNTs (m-HNTs) or pristine HNTs, manifesting an indication of enhanced filler-rubber interfacial interaction in SBR/HNTs-s-CZ nanocomposites. Consequently, SBR/HNTs-s-CZ nanocomposites showed excellent mechanical properties. The tensile strength could be enhanced by as much as 38.6% and 102.5% compared to those of SBR/m-HNTs and SBR/HNTs nanocomposites, respectively, though containing equivalent accelerant component. The value of this work lies in the fact that apparent properties improvement of elastomer composites has been achieved by the incorporation of vulcanization accelerant-functionalized HNTs, which may be fruitful for the rational design of filler surface treatment and offer new scientific and technological opportunities for the preparation of high performance elastomer composites.

  12. Aspectos históricos da vulcanização Historical aspects of vulcanization

    Directory of Open Access Journals (Sweden)

    Helson M. da Costa

    2003-06-01

    Full Text Available As borrachas, para serem convertidas em materiais úteis do ponto de vista de aplicações, precisam ser misturadas a alguns ingredientes, os quais vão lhes dar as características desejadas para, então, serem vulcanizadas. Neste artigo, os aspectos históricos da vulcanização são abordados bem como a evolução dos aditivos essenciais à maioria das formulações.Rubbers, to be turned into useful materials from the commercial applications point of view, need the addition of a few other ingredients which, upon vulcanization, will impart the desired characteristics to the material. In this paper, historical aspects of vulcanization are revised as well as the evolution of the additives used in most of the formulations.

  13. Development of medical tube fabrication process from RVNRL: optimization and extrusion device at low temperature

    International Nuclear Information System (INIS)

    Collantes, Hugo David Chirinos

    1999-01-01

    The natural rubber latex was formulated, irradiation vulcanized and stabilized (GAMATEX) to make rubber goods for medical purpose. When the latex was vulcanized by gamma rays the effectiveness crosslinking of GAMATEX relationship between the concentration ratio of sensitizer system (x 1 =[n-BA]/[KOH]) and the vulcanization dose (x 2 ), showing high interaction grade. The RVNRL process was optimized for low vulcanization doses and high concentrations of n-BA. The resistance to radiolytic oxidation of rubber obtained from GAMATEX was attained when one antioxidants mixture (45% BANOX S + 55% TNPP) was added. This mixture exhibited synergetic effect. The latex showed pseudoplastic rheological behavior and the yield stress occurrence. The irreversible destabilization rate of latex was direct proportional to [n-BA] and indirect proportional to [KOH]. The post-irradiation effects or reversible destabilization of latex occurred because there is a residual concentration of [n-BA] that it was not reacted. The colloidal stability of GAMATEX improved with irradiation, showing showing the increase of thixotropic behavior and the tendency to Newtonian behavior flow besides the relationship between the viscosity index (k) and the pseudoplastic index (n). This fact allows the higher storage time of GAMATEX. The relative viscosity of latex was relationship between the temperature and the total dry rubber content according to the mathematical model: log ηrel = 0,18+1,09r w , where r w is the ratio (BS/100-BS). The radiation vulcanized latex coagulated at -10 deg C into the projected freezing system. (author)

  14. Preparation of micro-pored silicone elastomer through radiation crosslinking

    International Nuclear Information System (INIS)

    Gao Xiaoling; Gu Mei; Xie Xubing; Huang Wei

    2013-01-01

    The radiation crosslinking was adopted to prepare the micro-pored silicone elastomer, which was performed by vulcanization and foaming respectively. Radiation crosslinking is a new method to prepare micro-pored material with high performance by use of radiation technology. Silicon dioxide was used as filler, and silicone elastomer was vulcanized by electron beams, then the micro-pored material was made by heating method at a high temperature. The effects of absorbed dose and filler content on the performance and morphology were investigated. The structure and distribution of pores were observed by SEM. The results show that the micro-pored silicon elastomer can be prepared successfully by controlling the absorbed dose and filler content. It has a smooth surface similar to a rubber meanwhile the pores are round and unconnected to each other with the minimum size of 14 μm. And the good mechanical performance can be suitable for further uses. (authors)

  15. Some notes on the activities of R and D of radiation processing and their prospects toward the year 2000 in Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Manurung, S.; Chosdu, R.; Marga, U.; Natsir, M.; Danu, S.; Hilmy, N. [Center for Research and Development of Isotopes and Radiation Technologies, National Nuclear Energy Agency, Jakarta (Indonesia)

    2000-03-01

    Research and Development activities in radiation polymerization, sterilization, food preservation and radiation dosimetry started in early 1970. The basic idea of R and D is to strengthen and broaden the linkage between industry and research institute, which in turn results in the economic growth of the country. Past experiences in radiation vulcanization of natural rubber latex (RVNRL), wood surface coating, sterilization, and food preservation activities have given some benefits to industry as well as to the research in term of transfer of technology and know-how. Intended for commercial purposes, the radiation technology has been applied by two national private companies i.e. PT. Indogamma and PT. Gajah Tunggal, while in the lab. scale activities of BATAN, R and D are focused on the development of methodology. However, some problems related to existing resources, i.e. finance, machine, legal, psycho-social, have to be solved thoroughly in order to obtain maximum results and benefits national wide. At present, there are 6 Gamma Irradiators and 3 Electron Accelerators to carry out all the radiation processing activities, and it is our primary commitment to develop the methodology and its applications toward the year 2000. For this reason, collaboration with all of relevant institutes or organizations is considered to be urgent and important. (author)

  16. Some notes on the activities of R and D of radiation processing and their prospects toward the year 2000 in Indonesia

    International Nuclear Information System (INIS)

    Manurung, S.; Chosdu, R.; Marga, U.; Natsir, M.; Danu, S.; Hilmy, N.

    2000-01-01

    Research and Development activities in radiation polymerization, sterilization, food preservation and radiation dosimetry started in early 1970. The basic idea of R and D is to strengthen and broaden the linkage between industry and research institute, which in turn results in the economic growth of the country. Past experiences in radiation vulcanization of natural rubber latex (RVNRL), wood surface coating, sterilization, and food preservation activities have given some benefits to industry as well as to the research in term of transfer of technology and know-how. Intended for commercial purposes, the radiation technology has been applied by two national private companies i.e. PT. Indogamma and PT. Gajah Tunggal, while in the lab. scale activities of BATAN, R and D are focused on the development of methodology. However, some problems related to existing resources, i.e. finance, machine, legal, psycho-social, have to be solved thoroughly in order to obtain maximum results and benefits national wide. At present, there are 6 Gamma Irradiators and 3 Electron Accelerators to carry out all the radiation processing activities, and it is our primary commitment to develop the methodology and its applications toward the year 2000. For this reason, collaboration with all of relevant institutes or organizations is considered to be urgent and important. (author)

  17. RESEARCH ON THE HOMOGENEITY OF TEMPERATURES IN JOINT'S AREA BY VULCANIZING THE CONVEYOR BELTS

    Directory of Open Access Journals (Sweden)

    Dan DOBROTA

    2016-05-01

    Full Text Available The researches presented in this paper have followed the analysis of the heat transfer mode during joining through vulcanization of the conveyor belts and also the homogeneity of the temperatures in the joint area. The researches were made under laboratory conditions taking into account the process of joining of two conveyor belts of the type ST 2000 with an installation of the type DSLQ. Temperature measurement was conducted using an EX42570 pyrometer in four distinct points corresponding to each end of the two conveyor belts on the both sides of the band, namely the active and inactive side.

  18. Characterization of blends of PP and SBS vulcanized with gamma irradiation

    International Nuclear Information System (INIS)

    Gonzalez, J.; Albano, C.; Candal, M.V.; Ichazo, M.N.; Hernandez, M.

    2005-01-01

    The present work has the objective of analyzing blends of PP with 30 wt% SBS vulcanized with gamma irradiation. In order to do so, SBS was irradiated at 10, 25 and 50 kGy with gamma rays. Results indicate that the gel fraction increases with irradiation dose, varying from 0.3% to 13.0% for the doses employed. Concerning tensile properties, it can be seen that the incorporation of SBS non-irradiated or irradiated decreases Young's modulus, while increasing elongation at break. Respect to thermal studies, it was detected that SBS decreases melting enthalpy of blends, fact that implies a decrease on crystallinity degree, being this effect more noticeable when SBS is irradiated at doses higher than 10 kGy. On the other hand, melting temperature diminishes slightly when adding SBS to PP, but does not show significant variations when SBS is irradiated. PPs MFI decreased with the addition of SBS, being the effect more notorious with irradiation dose. Finally, it can be concluded that SBS can be vulcanized by gamma irradiation, and that the crosslinking degree increases with irradiation dose

  19. Properties of Vulcanized Polyisoprene Rubber Composites Filled with Opalized White Tuff and Precipitated Silica

    Directory of Open Access Journals (Sweden)

    Suzana Samaržija-Jovanović

    2014-01-01

    Full Text Available Opalized white tuff (OWT with 40 μm average particle size and 39.3 m2/g specific surface area has been introduced into polyisoprene rubber (NR. Their reinforcing effects were evaluated by comparisons with those from precipitated silica (PSi. The cure characteristic, apparent activation energy of cross-link (Eac and reversion (Ear, and mechanical properties of a variety of composites based on these rubbers were studied. This was done using vulcanization techniques, mechanical testing, and scanning electron microscopy (SEM. The results showed that OWT can greatly improve the vulcanizing process by shortening the time of optimum cure (tc90 and the scorch time (ts2 of cross-linked rubber composites, which improves production efficiency and operational security. The rubber composites filled with 50 phr of OWT were found to have good mechanical and elastomeric properties. The tensile strengths of the NR/OWT composites are close to those of NR/PSi composites, but the tear strength and modulus are not as good as the corresponding properties of those containing precipitated silica. Morphology results revealed that the OWT is poorly dispersed in the rubber matrix. According to that, the lower interactions between OWT and polyisoprene rubber macromolecules are obtained, but similar mechanical properties of NR/OWT (100/50 rubber composites compared with NR/PSi (100/50 rubber composites are resulted.

  20. Surface modification of argon/oxygen plasma treated vulcanized ethylene propylene diene polymethylene surfaces for improved adhesion with natural rubber

    International Nuclear Information System (INIS)

    Basak, Ganesh C.; Bandyopadhyay, Abhijit; Neogi, Sudarsan; Bhowmick, Anil K.

    2011-01-01

    Vulcanized ethylene propylene diene polymethylene (EPDM) rubber surface was treated in a radio frequency capacitatively coupled low pressure argon/oxygen plasma to improve adhesion with compounded natural rubber (NR) during co-vulcanization. The plasma modified surfaces were analyzed by means of contact angle measurement, surface energy, attenuated total reflection-infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive X-ray sulfur mapping and atomic force microscopy. Several experimental variables such as plasma power, length of exposure time and composition of the argon-oxygen gas mixture were considered. It was delineated that plasma treatment changed both surface composition and roughness, and consequently increased peel strength. The change in surface composition was mainly ascribed to the formation of C-O and -C=O functional groups on the vulcanized surfaces. A maximum of 98% improvement in peel strength was observed after plasma treatment.

  1. Surface modification of argon/oxygen plasma treated vulcanized ethylene propylene diene polymethylene surfaces for improved adhesion with natural rubber

    Energy Technology Data Exchange (ETDEWEB)

    Basak, Ganesh C. [Rubber Technology Centre, Indian Institute of Technology, Kharagpur 721302 (India); Bandyopadhyay, Abhijit [Department of Polymer Science and Technology, University of Calcutta, Calcutta 700 009 (India); Neogi, Sudarsan [Department of Chemical Engineering, Indian Institute of Technology, Kharagpur 721302 (India); Bhowmick, Anil K., E-mail: anilkb@rtc.iitkgp.ernet.in [Rubber Technology Centre, Indian Institute of Technology, Kharagpur 721302 (India)

    2011-01-15

    Vulcanized ethylene propylene diene polymethylene (EPDM) rubber surface was treated in a radio frequency capacitatively coupled low pressure argon/oxygen plasma to improve adhesion with compounded natural rubber (NR) during co-vulcanization. The plasma modified surfaces were analyzed by means of contact angle measurement, surface energy, attenuated total reflection-infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive X-ray sulfur mapping and atomic force microscopy. Several experimental variables such as plasma power, length of exposure time and composition of the argon-oxygen gas mixture were considered. It was delineated that plasma treatment changed both surface composition and roughness, and consequently increased peel strength. The change in surface composition was mainly ascribed to the formation of C-O and -C=O functional groups on the vulcanized surfaces. A maximum of 98% improvement in peel strength was observed after plasma treatment.

  2. Multifunctional Peroxidegas Alternative Crosslink Agents for Dynamically Vulcanized Expoxidized Natural Rubber/Polypropylene Blends

    NARCIS (Netherlands)

    Thitithammawong, A.; Thitithammawong, A.; Sahakaro, Kannika; Noordermeer, Jacobus W.M.

    2009-01-01

    Commonly used dicumyl peroxide (DCP) in combination with coagent, triallyl cyanurate (TAC), as a crosslinking agent is well acceptable for dynamically vulcanized rubber phase of thermoplastic vulcanizates (TPVs). However, it generally produces volatile decomposition products, which cause a typical

  3. Thermosetting materials of the radiation-modified polymer compositions. 3. Development of thermoplastic thermosetting materials from polymeric blends

    International Nuclear Information System (INIS)

    Kalkis, V.; Zicans, J.; Bocoka, T.; Ivanova, T.

    2000-01-01

    Experimental studies of blends consisting of chemically and radiation modified polyethylene and ethylene-propylene-diene copolymers have been carried out. Measurements of crystallinity, toughness, viscoelastic, adhesion and thermorelaxation properties as well as scanning electron-microscopic studies have shown that the blends chemically vulcanized by elastomer phase crosslinking system possess a typical double-phase structure within the whole composition range and characteristics specific for rubber, whereas, in radiation-vulcanized blends where crosslinking of both disperse phases takes part, formation of chemical bonds between these phases was observed. Consequently, the radiation treatment improves the properties of the blends, and materials formed by such a system can be successfully used, e.g., as elastic and adhesion active thermosetting materials if the polymer is previously oriented. (author)

  4. Crosslinked bicontinuous biobased PLA/NR blends via dynamic vulcanization using different curing systems.

    Science.gov (United States)

    Yuan, Daosheng; Chen, Kunling; Xu, Chuanhui; Chen, Zhonghua; Chen, Yukun

    2014-11-26

    In this study, blends of entirely biosourced polymers, namely polylactide (PLA) and natural rubber (NR), were prepared through dynamic vulcanization using dicumyl peroxide (DCP), sulphur (S) and phenolic resin (2402) as curing agents, respectively. The crosslinked NR phase was found to be a continuous structure in all the prepared blends. The molecular weight changes of PLA were studied by gel permeation chromatography. Interfacial compatibilization between PLA and NR was investigated using Fourier transform infrared spectroscopy and scanning electron microscopy. The thermal properties of blends were evaluated by differential scanning calorimetry and thermogravimetric analysis instrument. It was found that the molecular weight of PLA and interfacial compatibilizaion between PLA and NR showed a significant influence on the mechanical and thermal properties of blends. The PLA/NR blend (60/40 w/w) by DCP-induced dynamic vulcanization owned the finest mechanical properties and thermal stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. THE NUMERICAL ALGORITHM FOR CALCULATING TEMPERATURE FIELDS OF THE PNEUMATIC TIRES DURING VULCANIZATION

    Directory of Open Access Journals (Sweden)

    S. G. Tikhomirov

    2015-01-01

    Full Text Available In the article discussed the mathematical formulation and numerical algorithm for solving the problem of calculating the temperature field in the process vulcanizing of the product, whose the thermal characteristics are depended on the temperature. As a mathematical model considered the system of differential equations of heat conduction, taking into account the change in the coefficients of thermal conductivity and heat density in multilayer product of the temperature. The system of equations is solved for a given initial distribution of temperature and for a given (time-dependent temperatures on the border of the product to the press-mold and to the diaphragm. On the border of the contacts of adjacent layers are given the condition of continuity of temperature and heat flux. Change of the thermal conductivity from the time is approximated by linear functions. The activation energy of the vulcanization process is determined on the basis of experimental data obtained in the control test samples using a reometer. Considering the function representing the corresponding integrals of the thermal conductivity, the original system of differential equations is transformed to an equivalent system of differential equations convenient for constructing numerical algorithms for solving the problem. The resulting system of partial differential equations derived using the method of finite-difference approximation is replaced by a system of algebraic equations. Solution of the system of algebraic equations is carried out under the scheme explicit difference approximation. In the article calculated the temperature field for the tire at given initial and boundary conditions. Stability and accuracy of the numerical algorithm for solving the problem is demonstrated by the calculations performed with different sampling step along the time and space coordinates. Assessment of the degree of completion of the process is carried out by calculated equivalent time for

  6. GURU v2.0: An interactive Graphical User interface to fit rheometer curves in Han’s model for rubber vulcanization

    OpenAIRE

    Milani, G.; Milani, F.

    2016-01-01

    A GUI software (GURU) for experimental data fitting of rheometer curves in Natural Rubber (NR) vulcanized with sulphur at different curing temperatures is presented. Experimental data are automatically loaded in GURU from an Excel spreadsheet coming from the output of the experimental machine (moving die rheometer). To fit the experimental data, the general reaction scheme proposed by Han and co-workers for NR vulcanized with sulphur is considered. From the simplified kinetic scheme adopted, ...

  7. Radiation pre-vulcanization of transitional layer of all-steel load meridian tyre and performance tests of the tyre products

    International Nuclear Information System (INIS)

    Zhang Benshang; Zhu Chengshen; Ying Shizhou; Liu Kebo; Li Zhaopeng; Li Kunhao; Zhang Hongna; Zhao Meihong; Yang Mingcheng

    2012-01-01

    In this article, natural rubber is chosen as transitional layer of all-steel load meridian tyre, which is pre-vulcanized by 500 keV E-beam irradiation of up to 60 kGy. The results show that the Green strength of transitional layer increases with the dose, reaching four times at 60 kGy as much as the control (without irradiation). The viscosity of transitional layer increases rapidly below about 29 kGy, but changes little at higher doses. The final mechanical properties do not differ significantly from those of the control. However, thickness of the natural rubber transitional layer for an average single tire can be reduced by 1 mm (or 1.5 kg), without obvious adverse effect on the tyre performance. (authors)

  8. Radiation technology in the Philippines

    International Nuclear Information System (INIS)

    Cabalfin, E.G.

    1994-01-01

    This report was presented during the Second National Coordinators Meeting for radiation technology, held in Vietnam, 21-25 November 1994. The report was about the research and development work in the field of radiation technology at the Philippine Nuclear Research Institute. Transfer of technology in the Philippines can be very difficult without the technical assistance of the IAEA. A multipurpose irradiation facility was set up that encouraged the interest of local industry in radiation sterilization and food irradiation. Also research and development on radiation vulcanization of natural rubber latex has been initiated and the interest in wood plastic combinations has been revived. 1 tab

  9. Degradation of blending vulcanized natural rubber and nitril rubber (NR/NBR) by dimethyl ether through variation of elastomer ratio

    Science.gov (United States)

    Saputra, A. H.; Juneva, S.; Sari, T. I.; Cifriadi, A.

    2018-04-01

    Dimethyl ether can cause degradation of the rubber material seal in some applications. In order to use of natural rubber in industry, research about a blending of natural rubber (NR) and nitrile rubber (NBR) to produce rubber to meet the standard seal material application were conducted. This study will observe the degradation mechanisms that occur in the blending natural rubber and nitrile rubber (NR/NBR) by dimethyl ether. Nitrile rubber types used in this study is medium quality nitrile rubber with 33% of acrylonitrile content (NBR33). The observed parameters are percent change in mass, mechanical properties and surface morphology. This study is limited to see the effect of variation vulcanized blending ratio (NR/NBR33) against to swelling. The increase of nitrile rubber (NBR33) ratio of blending rubber vulcanized can reduce the tensile strength and elongation. The best elastomer variation was obtained after comparing with the standard feasibility material of seal is rubber vulcanized blending (NR/NBR33) with ratio 40:60 NR: NBR.

  10. An Automated DAKOTA and VULCAN-CFD Framework with Application to Supersonic Facility Nozzle Flowpath Optimization

    Science.gov (United States)

    Axdahl, Erik L.

    2015-01-01

    Removing human interaction from design processes by using automation may lead to gains in both productivity and design precision. This memorandum describes efforts to incorporate high fidelity numerical analysis tools into an automated framework and applying that framework to applications of practical interest. The purpose of this effort was to integrate VULCAN-CFD into an automated, DAKOTA-enabled framework with a proof-of-concept application being the optimization of supersonic test facility nozzles. It was shown that the optimization framework could be deployed on a high performance computing cluster with the flow of information handled effectively to guide the optimization process. Furthermore, the application of the framework to supersonic test facility nozzle flowpath design and optimization was demonstrated using multiple optimization algorithms.

  11. Blendas PVC/NBR por processamento reativo I: desenvolvimento do processo de vulcanização Dinâmica in situ PVC/NBR blends by reactive processing I: in situ dynamic vulcanization process

    Directory of Open Access Journals (Sweden)

    Fábio R. Passador

    2007-06-01

    Full Text Available Vulcanização dinâmica é o processo de vulcanização de um elastômero durante a mistura no estado fundido com um termoplástico, que resulta em uma classe de materiais denominada termoplásticos vulcanizados. Neste trabalho, um novo tipo de termoplástico vulcanizado foi obtido por vulcanização dinâmica in situ da blenda PVC/NBR, utilizando-se um sistema de cura a base de enxofre (S e combinação dos aceleradores 2,2-ditiomercaptobenzotiazol (MBTS e dissulfeto de tetrametiltiuram (TMTD. As blendas PVC/NBR (90/10, 80/20 e 70/30% em massa foram processadas em um reômetro de torque Haake (Rheomix 600 a 160 °C com rotação de 60 rpm. As blendas obtidas por processamento reativo foram caracterizadas por calorimetria diferencial de varredura (DSC para determinação do grau de cura. Observou-se aumento no grau de cura das blendas com o tempo de mistura sendo o sistema de cura considerado eficiente.Dynamic vulcanization is a process of vulcanization of an elastomer during melt mixing with a thermoplastic wich results in material called thermoplastic vulcanizates or TPVs. In this study, a new kind of TPV was obtained by in situ dynamic curing of poly(vinyl chloride (PVC/nitrile rubber (NBR blends. The crosslinking of PVC/NBR blends was accomplished using sulphur (S/tetramethylthiuram disulphide (TMTD and mercaptobenzthiazyl disulphide (MBTS curative system during the reactive processing. The blends of PVC/NBR at the ratio of 90/10; 80/20 and 70/30 wt. (% were melt mixed using a Haake Rheomix 600 at 160 °C and rotor speed of 60 rpm. The curing behavior of NBR was investigated by a Monsanto Rheometer and the degree of cure was calculated using differential scanning calorimetry (DSC for different mixing times. It was observed that the degree of cure increases with the mixing time and the crosslinking system used in this work was considered efficient.

  12. Application of radiation in Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Naiyyum Choudhury; Najmul Alam Chowdhury; Feroza Akhtar [Bangladesh Atomic Energy Commission, Dhaka (Bangladesh)

    2001-03-01

    Radiation technology offers a very wide scope for utilisation and commercial exploitation in various field. All over the world, this technology is being favourably considered for different applications like radiation sterilisation of medical products, preservation of food by controlling the physiological processes for extending shelf-life and eradication of microbial and insect pests, radiation processing of polymeric materials and treatment of sewage sludge. Bangladesh Atomic Energy Commission has taken radiation processing programmes in a big way right from its inception. This paper describes the studies carried out by various research groups in Bangladesh Atomic Energy Commission mainly using Cobalt-60 gamma radiation. The investigation covers medical sterilisation, food preservation and development and modification of polymeric materials by gamma radiation. Both food preservation and radiation sterilisation of medical products are now being commercially carried out in the Gammatech facility as a joint venture company of BAEC and a private entrepreneur. Bangladesh is soon going to establish a full-fledged Tissue Bank to cater the needs of various tissue allografts for surgical replacement. Recently Government of Bangladesh has allocated US$ 1.00 million for strengthening of the Tissue Banking Laboratory. BAEC has made quite a good research contribution on vulcanization of natural rubber latex, wood plastic composites, surface coating curing, polymer modification etc. As a result of successful achievement of R and D activities in all these projects, a pilot plant project involving about US$ 4.00 million is under implementation at the Atomic energy Research Establishment campus of BAEC. In addition a project on 'National Polymer Centre' at a cost of US$ 2.00 million has already been approved. It is expected that work on radiation processing including commercialization will be accelerated with the implementation of these projects. The impact of radiation

  13. Application of radiation in Bangladesh

    International Nuclear Information System (INIS)

    Naiyyum Choudhury; Najmul Alam Chowdhury; Feroza Akhtar

    2001-01-01

    Radiation technology offers a very wide scope for utilisation and commercial exploitation in various field. All over the world, this technology is being favourably considered for different applications like radiation sterilisation of medical products, preservation of food by controlling the physiological processes for extending shelf-life and eradication of microbial and insect pests, radiation processing of polymeric materials and treatment of sewage sludge. Bangladesh Atomic Energy Commission has taken radiation processing programmes in a big way right from its inception. This paper describes the studies carried out by various research groups in Bangladesh Atomic Energy Commission mainly using Cobalt-60 gamma radiation. The investigation covers medical sterilisation, food preservation and development and modification of polymeric materials by gamma radiation. Both food preservation and radiation sterilisation of medical products are now being commercially carried out in the Gammatech facility as a joint venture company of BAEC and a private entrepreneur. Bangladesh is soon going to establish a full-fledged Tissue Bank to cater the needs of various tissue allografts for surgical replacement. Recently Government of Bangladesh has allocated US$ 1.00 million for strengthening of the Tissue Banking Laboratory. BAEC has made quite a good research contribution on vulcanization of natural rubber latex, wood plastic composites, surface coating curing, polymer modification etc. As a result of successful achievement of R and D activities in all these projects, a pilot plant project involving about US$ 4.00 million is under implementation at the Atomic energy Research Establishment campus of BAEC. In addition a project on 'National Polymer Centre' at a cost of US$ 2.00 million has already been approved. It is expected that work on radiation processing including commercialization will be accelerated with the implementation of these projects. The impact of radiation processing

  14. Application of radiation in Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Choudhury, Naiyyum; Chowdhury, Najmul Alam; Akhtar, Feroza [Bangladesh Atomic Energy Commission, Dhaka (Bangladesh)

    2001-03-01

    Radiation technology offers a very wide scope for utilisation and commercial exploitation in various field. All over the world, this technology is being favourably considered for different applications like radiation sterilisation of medical products, preservation of food by controlling the physiological processes for extending shelf-life and eradication of microbial and insect pests, radiation processing of polymeric materials and treatment of sewage sludge. Bangladesh Atomic Energy Commission has taken radiation processing programmes in a big way right from its inception. This paper describes the studies carried out by various research groups in Bangladesh Atomic Energy Commission mainly using Cobalt-60 gamma radiation. The investigation covers medical sterilisation, food preservation and development and modification of polymeric materials by gamma radiation. Both food preservation and radiation sterilisation of medical products are now being commercially carried out in the Gammatech facility as a joint venture company of BAEC and a private entrepreneur. Bangladesh is soon going to establish a full-fledged Tissue Bank to cater the needs of various tissue allografts for surgical replacement. Recently Government of Bangladesh has allocated US$ 1.00 million for strengthening of the Tissue Banking Laboratory. BAEC has made quite a good research contribution on vulcanization of natural rubber latex, wood plastic composites, surface coating curing, polymer modification etc. As a result of successful achievement of R and D activities in all these projects, a pilot plant project involving about US$ 4.00 million is under implementation at the Atomic energy Research Establishment campus of BAEC. In addition a project on 'National Polymer Centre' at a cost of US$ 2.00 million has already been approved. It is expected that work on radiation processing including commercialization will be accelerated with the implementation of these projects. The impact of radiation processing

  15. Development of new materials by utilizing radiation crosslinking

    International Nuclear Information System (INIS)

    Ueno, Keiji; Uda, Yujiro; Suzuki, Shizuo

    1989-01-01

    About 30 years have elapsed since the cables by electron beam crosslinking were developed as the first industrial utilization of radiation in Japan. At present about 200 electron beam accelerators are used industrially in Japan, and cable industry ranks at the top, followed by foaming polyethylene and curing, and the preliminary vulcanization of tires. The effect of these irradiations is the reforming of polymers by radiation crosslinking. In cables, the heat resistance and chemical resistance of insulators are improved by radiation crosslinking. By applying radiation crosslinking to polyurethane elastomer, its weakest point, waterproof property, was improved. Moreover, by using this crosslinked polyurethane elastomer for cable coating, the reliability of the sensor cables for brake system was able to be remarkably improved. As another new application of radiation crosslinking process, the improvement of the heat resistance of engineering plasties was examined. The structure of radiation crosslinked urethane elastomer cables, their endurance in hot water and oil, and the life, and the characteristics of sensor cables are reported. Multi-functional monomers, the molecular structure, and the various characteristics of engineering plastics are described. (K.I.)

  16. Vulcan Hot Springs known geothermal resource area: an environmental analysis

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, S.G.; Russell, B.F. (eds.)

    1979-09-01

    The Vulcan Hot Springs known geothermal resource area (KGRA) is one of the more remote KGRAs in Idaho. The chemistry of Vulcan Hot Springs indicates a subsurface resource temperature of 147/sup 0/C, which may be high enough for power generation. An analysis of the limited data available on climate, meteorology, and air quality indicates few geothermal development concerns in these areas. The KGRA is located on the edge of the Idaho Batholith on a north-trending lineament which may be a factor in the presence of the hot springs. An occasional earthquake of magnitude 7 or greater may be expected in the region. Subsidence or elevation as a result of geothermal development in the KGRA do not appear to be of concern. Fragile granitic soils on steep slopes in the KGRA are unstable and may restrict development. The South fork of the Salmon River, the primary stream in the region, is an important salmon spawning grounds. Stolle Meadows, on the edge of the KGRA, is used as a wintering and calving area for elk, and access to the area is limited during this period. Socioeconomic and demographic surveys indicate that facilities and services will probably not be significantly impacted by development. Known heritage resources in the KGRA include two sites and the potential for additional cultural sites is significant.

  17. Antioxidant and sensitizer effect on the stability of natural rubber latex vulcanized by gamma rays

    International Nuclear Information System (INIS)

    Canavel, V.

    1993-01-01

    The natural rubber latex was vulcanized by gamma rays and electrons beam, in the presence and absence of sensitizer at room temperature. The sensitizers were the following; n-butyl acrylate (n-BA) / t-butyl hydroperoxide (t-B H) / KOH, C Cl 4 / potassium laurate and n-BA / KOH. The studied antioxidants, Irganox 1520, Vulcanox SP and Vulcanox BKF, were added to the latex after irradiation. Among the studied antioxidants in function of tensile strength (TS) after the aging of rubber plates, the Irganox was the best efficient on the gamma vulcanization in the presence of n-BA/t-B H/KOH, because only 0,20 p hr is enough to obtain the greatest increase of TS, that was 34%, 12 MPa to 16 MPa. The formulating method of latex with the sensitizer constituted the 3,0 p hr of n-BA/ 0,1 p hr of t-B H and 0,2 p hr of KOH, was evaluated respecting the TS of rubber plates. The electrons beam vulcanization produces the greatest reversible perturbance in the colloidal stability of latex after irradiation caused by radiolytic species absorption that promotes the increase of particle size. The antioxidant also contributes to reversible destabilization of gamma irradiated latex, because it is also adsorbed by particles surface. The relation between the latex viscosity and the TS of respective rubber plates is reverse, showing the latex stability affects the quality of rubber goods. (author)

  18. Rubber - application of radiation to tire manufacture

    International Nuclear Information System (INIS)

    Hunt, J.D.; Alliger, G.

    1979-01-01

    Since the advent of commercial accelerators during the last several years capable of producing controllable electron beams of high energy, Firestone has devoted a considerable effort to the better understanding of the possible applications of such radiation to the production of tires or tire components. A number of chemical reactions can occur when elastomeric compounds are exposed to high energy waves, but crosslinking and degradation are the most important. The degree to which the crosslinking reaction predominates depends upon the nature of the rubber, compounding ingredients and the dosage. In general then, the effects achieved by the radiation of a rubber are quite similar to those resulting from heat. However, radiation cure or precure of compounds offers the advantage that the degree of crosslinking can be better controlled. Uniform crosslinking is possible since the high speed electrons penetrate uniformly throughout the sample. Curing with heat on the other hand may result in a greater degree of crosslinking on the surface of the sample than the center because of low heat conductivity. In general, radiation can be used to advantage to crosslink partially rubber tire components so that they retain better their shape and dimension during tire assembly and final cure or vulcanization. Added advantages of radiation precure include: a reduction of material usage, substitution of synthetic for natural rubber without loss in strength and the fact that partially crosslinked components will not thin out or become displaced during construction and vulcanization of the tire. (author)

  19. Effect of gamma radiation dose and sensitizer on the physical properties of irradiated natural rubber latex

    International Nuclear Information System (INIS)

    Komgrit, R.; Thawat, C.; B, Tripob; Wirach, T.

    2009-07-01

    Full text: The vulcanization of natural rubber latex can be induced by gamma radiation, which enhances cross-linking within the rubber matrix. The purpose of this research is to investigate the effect of gamma radiation dose and sensitizers on the physical properties of irradiated natural rubber. Three sensitizers n-butyl acrylate (n-B A), tetrachloroethylene (C 2 Cl 4 ) and trichloromethane (CHCl 3 ) were mixed with natural rubber latex before irradiation with gamma ray dose varied from 14 to 22 kGy. Results showed that the mixture of three sensitizers with specific ratios effectively induced the cross-linking of natural rubber latex. The cross-linking ratio and improved physical properties increased with increasing gamma dose. Therefore, the mixture ratios of n-B A, C 2 Cl 4 and CHCl 3 have shown to be a critical parameter in the vulcanization of natural rubber latex by gamma radiation

  20. Processing cost of RVNRL (Radiation Vulcanised Natural Rubber Latex)

    International Nuclear Information System (INIS)

    Wan Manshol Wan Zin; Meor Yahya Razali; Norjanah Mohd

    1996-01-01

    The main components contributing to the cost of building a pilot plant for RVNRL are highlighted. The fixed cost and operating cost of a pilot plant were determined and the production capacity and the cost to prepare I kg of RVNRL were calculated. Two sets of calculations were presented. A set was based on a pilot plant installed with cobalt-60 source of 150 kCi and another set was based on a plant installed with cobalt-60 source of I MCi. The effect of different power utilisation efficiencies and the effect of different vulcanization doses on the production capacities are presented.In general, a small difference in the vulcanization dose and power utilisation efficiency result in a significant change in the production capacity and the cost for RVNRL preparation. Depending on the production capacity, the cost for preparing RVNRL of 50% total solid content can be as low as RM 0.242 per kilograms

  1. Vulcan: A steady-state tokamak for reactor-relevant plasma–material interaction science

    International Nuclear Information System (INIS)

    Olynyk, G.M.; Hartwig, Z.S.; Whyte, D.G.; Barnard, H.S.; Bonoli, P.T.; Bromberg, L.; Garrett, M.L.; Haakonsen, C.B.; Mumgaard, R.T.; Podpaly, Y.A.

    2012-01-01

    Highlights: ► A new scaling for obtaining reactor similarity in the divertor of scaled tokamaks. ► Conceptual design for a tokamak (“Vulcan”) to implement this new scaling. ► Demountable superconducting coils and compact neutron shielding. ► Helium-cooled high-temperature vacuum vessel and first wall. ► High-field-side lower hybrid current drive for non-inductive operation. - Abstract: An economically viable magnetic-confinement fusion reactor will require steady-state operation and high areal power density for sufficient energy output, and elevated wall/blanket temperatures for efficient energy conversion. These three requirements frame, and couple to, the challenge of plasma–material interaction (PMI) for fusion energy sciences. Present and planned tokamaks are not designed to simultaneously meet these criteria. A new and expanded set of dimensionless figures of merit for PMI have been developed. The key feature of the scaling is that the power flux across the last closed flux surface P/S ≃ 1 MW m −2 is to be held constant, while scaling the core volume-averaged density weakly with major radius, n ∼ R −2/7 . While complete similarity is not possible, this new “P/S” or “PMI” scaling provides similarity for the most critical reactor PMI issues, compatible with sufficient current drive efficiency for non-inductive steady-state core scenarios. A conceptual design is developed for Vulcan, a compact steady-state deuterium main-ion tokamak which implements the P/S scaling rules. A zero-dimensional core analysis is used to determine R = 1.2 m, with a conventional reactor aspect ratio R/a = 4.0, as the minimum feasible size for Vulcan. Scoping studies of innovative fusion technologies to support the Vulcan PMI mission were carried out for three critical areas: a high-temperature, helium-cooled vacuum vessel and divertor design; a demountable superconducting toroidal field magnet system; and a steady-state lower hybrid current drive system

  2. The Effect of Minarex B Oil and Gamma Irradiation on the Mechanical Properties of Vulcanized Natural Rubber-LDPE Mixture for Shoe Sole

    International Nuclear Information System (INIS)

    Sudradjat Iskandar; Isni Marliyanti

    2004-01-01

    To obtain the optimum concentration of minarex B oil and gamma irradiation dose on natural rubber compound for shoe sole, study on the effect of minarex B oil and gamma radiation on the mechanical properties of vulcanized natural rubber-LDPE mixture has been done. Natural rubber was masticated and mixed with additive and filler using two-roll machine, at 120 o C of forward roll and 100 o C of backward roll, with rotation speed of 18 rpm. The additives added with irganox 1076, paraffin wax, stearic acid, and minarex B oil, while fillers used were polyethylene (LDPE) and calcium carbonate. Minarex B oil mixed was vary such as 5, 10 and 20 phr (part per hundred of rubber). The amount of filler and other additives mixed was not varied. The natural rubber film was obtained by pressing the mixture using hot and cold press machine at 135 o C and room temperature for about 3 minutes. The film then irradiated with gamma rays from cobalt-60 source, at the doses of 150, 300, and 500 kGy. The results show that the mechanical properties of natural rubber vulcanized decreases by increasing minarex B oil, and increases by increasing of irradiation dose. The concentration optimum of minarex B oil in the natural rubber compound for shoe sole and irradiation dose about 5 phr and 300 kGy were agree with SII 0944-84. (author)

  3. Elastomeric Nanocomposite Based on Exfoliated Graphene Oxide and Its Characteristics without Vulcanization

    OpenAIRE

    Nasser Abdullah Habib; Buong Woei Chieng; Norkhairunnisa Mazlan; Umer Rashid; Robiah Yunus; Suraya Abdul Rashid

    2017-01-01

    Rubber nanocomposites have emerged as one of the advanced materials in recent years. The aim of this work was to homogeneously disperse graphene oxide (GO) sheets into Nitrile Butadiene Rubber (NBR) and investigate the characteristics of GO/NBR nanocomposite without vulcanization. A suitable solvent was found to dissolve dry NBR while GO was exfoliated completely in an aqueous base solution using sonication. GO was dispersed into NBR at different loadings by solution mixing to produce unvulca...

  4. Dosimetry for radiation processing

    DEFF Research Database (Denmark)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both...... and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading...

  5. Radiation processing of polysaccharides

    International Nuclear Information System (INIS)

    2004-11-01

    Radiation processing is a very convenient tool for imparting desirable effects in polymeric materials and it has been an area of enormous interest in the last few decades. The success of radiation technology for processing of synthetic polymers can be attributed to two reasons namely, their ease of processing in various shapes and sizes, and secondly, most of these polymers undergo crosslinking reaction upon exposure to radiation. In recent years, natural polymers are being looked at with renewed interest because of their unique characteristics, such as inherent biocompatibility, biodegradability and easy availability. Traditionally, the commercial exploitation of natural polymers like carrageenans, alginates or starch etc. has been based, to a large extent, on empirical knowledge. But now, the applications of natural polymers are being sought in knowledge - demanding areas such as pharmacy and biotechnology, which is acting as a locomotive for further scientific research in their structure-function relationship. Selected success stories concerning radiation processed natural polymers and application of their derivatives in the health care products industries and agriculture are reported. This publication will be of interest to individuals at nuclear institutions worldwide that have programmes of R and D and applications in radiation processing technologies. New developments in radiation processing of polymers and other natural raw materials give insight into converting them into useful products for every day life, human health and environmental remediation. The book will also be of interest to other field specialists, readers including managers and decision makers in industry (health care, food and agriculture) helping them to understand the important role of radiation processing technology in polysaccharides

  6. Perspective of radiation processing

    International Nuclear Information System (INIS)

    Zhang Manwei

    1987-01-01

    The area of the applications of radiation techniques is very wide. This paper only relates to the applications of radiation techniques in industries including radiation chemical industry, radiation processing of foods and environmental protection by radiation, but the nuclear instruments and the instrumentations of radiation are out-side of our study. (author)

  7. Influence of different curing systems on the physico-mechanical properties and stability of SBR and NR rubbers

    Energy Technology Data Exchange (ETDEWEB)

    Basfar, A.A. E-mail: abasfar@kacst.edu.sa; Abdel-Aziz, M.M.; Mofti, S

    2002-01-01

    The physical properties of radiation, sulfur and peroxide-cured styrene-butadiene rubber (SBR) and natural rubber (NR) were compared. The dependence of the mechanical properties of the radiation-vulcanized SBR and NR on the coagent concentration and radiation dose was studied. The effect of thermal aging on the mechanical properties of the different rubber formulations was discussed. The radiation-cured formulations of SBR have superior mechanical properties and thermal stability compared with those of the chemically vulcanized compounds. Whereas, the radiation-cured formulations of NR have similar mechanical properties but superior thermal stability (based on the % change in E after thermal aging), when compared with those of the sulfur-vulcanized compounds and slightly better than those of the peroxide-vulcanized compounds.

  8. Radiation processes in astrophysics

    CERN Document Server

    Tucker, Wallace H

    1975-01-01

    The purpose of this book is twofold: to provide a brief, simple introduction to the theory of radiation and its application in astrophysics and to serve as a reference manual for researchers. The first part of the book consists of a discussion of the basic formulas and concepts that underlie the classical and quantum descriptions of radiation processes. The rest of the book is concerned with applications. The spirit of the discussion is to present simple derivations that will provide some insight into the basic physics involved and then to state the exact results in a form useful for applications. The reader is referred to the original literature and to reviews for rigorous derivations.The wide range of topics covered is illustrated by the following table of contents: Basic Formulas for Classical Radiation Processes; Basic Formulas for Quantum Radiation Processes; Cyclotron and Synchrotron Radiation; Electron Scattering; Bremsstrahlung and Collision Losses; Radiative Recombination; The Photoelectric Effect; a...

  9. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both by international organizations (IAEA) and national laboratories have helped to improve the reliability of dose measurements. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading to traceable and reliable dosimetry are discussed. (author)

  10. Effectiveness of the custom-mold room temperature vulcanizing silicone toe separator on hallux valgus: A prospective, randomized single-blinded controlled trial.

    Science.gov (United States)

    Chadchavalpanichaya, Navaporn; Prakotmongkol, Voraluck; Polhan, Nattapong; Rayothee, Pitchaya; Seng-Iad, Sirirat

    2018-04-01

    Silicone toe separator is considered as a conservative treatment for hallux valgus. The prefabricated toe separator does not fit all. However, effectiveness in prescription of the custom-mold toe separator is still unknown. To investigate the effect of using a custom-mold room temperature vulcanizing silicone toe separator to decrease hallux valgus angle and hallux pain. The compliances, complications, and satisfactions of toe separator were also explored. A prospective, randomized single-blinded controlled trial. A total of 90 patients with a moderate degree of hallux valgus were enrolled in a study at the Foot Clinic, Siriraj Hospital, Thailand. Patients were randomized into two groups; the study group was prescribed a custom-mold room temperature vulcanizing silicone toe separator for 6 h per night for 12 months. Patients in both groups received proper foot care and shoes and were permitted to continue drug treatment. In total, 40 patients in the study group and 39 patients in the control group completed the study. The hallux valgus angle was obtained through radiographic measurement. At month 12, both groups had significant differences in mean hallux valgus angle with a decrease of 3.3° ± 2.4° for the study group and increase of 1.9° ± 1.9° for the control group. There were statistically significant differences of hallux valgus angle between the two groups ( p Hallux pain was decreased in the study group. A custom-mold room temperature vulcanizing silicone toe separator can decrease hallux valgus angle and pain with no serious complications. Clinical relevance The custom-mold room temperature vulcanizing silicone toe separator for treatment of hallux valgus reduces deformity and hallux pain.

  11. Radiation processing of horticulture produce

    International Nuclear Information System (INIS)

    Khandal, R.K.

    2004-01-01

    The present paper deals with various aspects of radiation processing of horticultural products. The risk and success factors of the radiation processing units would be discussed, based on the experiences gained from the operation of Sac over a period of more than twenty years. Emphasis would be given to gamma radiation processing

  12. Radiation Vulcanization of Polymeric Blends Based on Ethylene Propylene Diene Monomer Rubber/ Waste Materials in Presence of Different Additives

    International Nuclear Information System (INIS)

    MOHAMED, R.M.

    2015-01-01

    In this investigation, the mechanical blending technique was applied for preparation of elastomeric blend of ethylene propylene diene monomer rubber (EPDM)and nitrile butadiene rubber (NBR) having a fixed ratio of (50/50) by weight. The prepared blend of EPDM/NBR (50/50) was used as a rubber matrix to be loaded with waste materials, namely rice husk (RH) as a natural waste filler and then with ground tire rubber (GTR) as an artificial one. The degree of loading varied from 5 p hr to 20 p hr. Ionizing radiation, namely ,gamma rays were applied for inducing vulcanization of prepared and loaded rubber blends, in the range from 5 kGy to 250 kGy. Different properties of prepared composites were followed up as a function of degree of loading with the waste material and dose of irradiation. The mechanical properties, namely tensile strength and elongation at break percent of the composites slightly decreased as the filler loading increased over the whole range of irradiation .Tensile modulus and hardness, on the other hand, showed an opposite trend, i.e. the increased. Other properties, namely physical, thermal and morphological confirmed the mechanical ones. Obtained results were affiliated with lack of interface adhesion between the waste materials and the rubber matrix elastomers. The lack of interface adhesion was improved by filling the composite with a limited content, up to 7 p hr, of the compatibilizer, namely, maleic anhydride (MAH). Measurements of different properties was carried out for composite loaded with 10 p hr of waste material. It has been found that the tensile properties were significantly improved with addition of the compatibilizing agent Further and significant improvement was attained in properties of prepared later composite by its loading with 40 p hr of either HAF- carbon black or Hisil as reinforcing fillers that participates in chemical as well as physical bonding. Similarly and lastly 8 p hr of N, N- methylene di acrylamide (MDA) were loaded

  13. Dosimetry and process control for radiation processing

    International Nuclear Information System (INIS)

    Mod Ali, N.

    2002-01-01

    Complete text of publication follows. Accurate radiation dosimetry can provide quality assurance in radiation processing. Considerable relevant experiences in dosimetry by the SSDL-MINT has necessitate the development of methods making measurement at gamma plant traceable to the national standard. It involves the establishment of proper calibration procedure and selection of appropriate transfer system/technique to assure adequate traceability to a primary radiation standard. The effort forms the basis for irradiation process control, the legal approval of the process by the public health authorities (medical product sterilization and food preservation) and the safety and acceptance of the product

  14. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    McLaughlin, W.L.; Boyd, A.W.; Chadwick, K.H.; McDonald, J.C.; Miller, A.

    1989-01-01

    Radiation processing is a relatively young industry with broad applications and considerable commercial success. Dosimetry provides an independent and effective way of developing and controlling many industrial processes. In the sterilization of medical devices and in food irradiation, where the radiation treatment impacts directly on public health, the measurements of dose provide the official means of regulating and approving its use. In this respect, dosimetry provides the operator with a means of characterizing the facility, of proving that products are treated within acceptable dose limits and of controlling the routine operation. This book presents an up-to-date review of the theory, data and measurement techniques for radiation processing dosimetry in a practical and useful way. It is hoped that this book will lead to improved measurement procedures, more accurate and precise dosimetry and a greater appreciation of the necessity of dosimetry for radiation processing. (author)

  15. Electrochemical behavior of nanostructured MnO2/C (Vulcan® composite in aqueous electrolyte LiNO3

    Directory of Open Access Journals (Sweden)

    Vujković Milica

    2011-01-01

    Full Text Available The electrolytic solutions of contemporary Li-ion batteries are made exclusively with the organic solvents since anodic materials of these batteries have potentials with greater negativity than the potential of the water reduction, thus the organic electrolytes can withstand the voltages of 3-5 V that are characteristic for these batteries. Ever since it was discovered that some materials can electrochemically intercalate and deintercalate Li+ ions in aqueous solutions, numerous studies have been conducted with the aim of extending operational time of the aqueous Li-ion batteries. Manganese oxide has been studied as the electrode material in rechargeable lithium-ion batteries with organic electrolytes. In this paper its electrochemical behavior as an anode material in aqueous electrolyte solutions was examined. MnO2 as a component of nanodispersed MnO2/C (Vulcan® composite was successfully synthesized hydrothermally. Electrochemical properties of this material were investigated in aqueous saturated LiNO3 solution by both cyclic voltammetry and galvanostatic charging/discharging (LiMn2O4 as cathode material techniques. The obtained composite shows a relatively good initial discharge capacity of 96.5 mAh/g which, after 50th charging/discharging cycles, drops to the value of 57mAh/g. MnO2/C (Vulcan® composite, in combination with LiMn2O4 as a cathode material, shows better discharge capacity compared to other anodic materials used in aqueous Li-ion batteries according to certain studies that have been conducted. Its good reversibility and cyclability, and the fact that hydrothermal method is simple and effective, makes MnO2/C(Vulcan® composite a promising anodic material for aqueous Li-ion batteries.

  16. Assessing the feasibility of a high-temperature, helium-cooled vacuum vessel and first wall for the Vulcan tokamak conceptual design

    International Nuclear Information System (INIS)

    Barnard, H.S.; Hartwig, Z.S.; Olynyk, G.M.; Payne, J.E.

    2012-01-01

    The Vulcan conceptual design (R = 1.2 m, a = 0.3 m, B 0 = 7 T), a compact, steady-state tokamak for plasma–material interaction (PMI) science, must incorporate a vacuum vessel capable of operating at 1000 K in order to replicate the temperature-dependent physical chemistry that will govern PMI in a reactor. In addition, the Vulcan divertor must be capable of handling steady-state heat fluxes up to 10 MW m −2 so that integrated materials testing can be performed under reactor-relevant conditions. A conceptual design scoping study has been performed to assess the challenges involved in achieving such a configuration. The Vulcan vacuum system comprises an inner, primary vacuum vessel that is thermally and mechanically isolated from the outer, secondary vacuum vessel by a 10 cm vacuum gap. The thermal isolation minimizes heat conduction between the high-temperature helium-cooled primary vessel and the water-cooled secondary vessel. The mechanical isolation allows for thermal expansion and enables vertical removal of the primary vessel for maintenance or replacement. Access to the primary vessel for diagnostics, lower hybrid waveguides, and helium coolant is achieved through ∼1 m long intra-vessel pipes to minimize temperature gradients and is shown to be commensurate with the available port space in Vulcan. The isolated primary vacuum vessel is shown to be mechanically feasible and robust to plasma disruptions with analytic calculations and finite element analyses. Heat removal in the first wall and divertor, coupled with the ability to perform in situ maintenance and replacement of divertor components for scientific purposes, is achieved by combining existing helium-cooled techniques with innovative mechanical attachments of plasma facing components, either in plate-type helium-cooled modules or independently bolted, helium-jet impingement-cooled tiles. The vacuum vessel and first wall design enables a wide range of potential PFC materials and configurations to

  17. Dose Assurance in Radiation Processing Plants

    DEFF Research Database (Denmark)

    Miller, Arne; Chadwick, K.H.; Nam, J.W.

    1983-01-01

    Radiation processing relies to a large extent on dosimetry as control of proper operation. This applies in particular to radiation sterilization of medical products and food treatment, but also during development of any other process. The assurance that proper dosimetry is performed...... at the radiation processing plant can be obtained through the mediation of an international organization, and the IAEA is now implementing a dose assurance service for industrial radiation processing....

  18. Development of rubber material for high radiation field

    International Nuclear Information System (INIS)

    Nakatsukasa, Sadayoshi; Tabasaki, Takeshi; Yoshida, Akihiro; Kadowaki, Yoshito

    2013-01-01

    Generally flexible polymeric materials exposed to radiation can't be used because they soften or harden remarkably in high radiation environment. Aromatic polymers such as PEEK, PI, and PES are also known as radiation-proof polymeric materials. Aromatic polymers are very hard, they can't be used for products like a packing where flexibility is required. We developed a new vulcanized rubber compound by the use of various additives and polymer blend. This developed rubber compound has a high radiation-proof performance by reaction balance of cross-linking and decomposition in this rubber. This rubber compound has a rubber elasticity even if exposed to radiation of MGy level, and its radiation proof is more than 5 times as high as conventional polymeric materials. This rubber compound is much more flexible than the aromatic polymers which are the used as conventional radiation-proof polymers. (author)

  19. Dosimetry systems for radiation processing

    International Nuclear Information System (INIS)

    McLaughlin, W.L.; Desrosiers, M.F.

    1995-01-01

    Dosimetry serves important functions in radiation processing, where large absorbed doses and dose rates from photon and electron sources have to be measured with reasonable accuracy. Proven dosimetry systems are widely used to perform radiation measurements in development of new processes, validation, qualification and verification (quality control) of established processes and archival documentation of day-to-day and plant-to-plant processing uniformity. Proper calibration and traceability of routine dosimetry systems to standards are crucial to the success of many large-volume radiation processes. Recent innovations and advances in performance of systems that enhance radiation measurement assurance and process diagnostics include dose-mapping media (new radiochromic film and solutions), optical waveguide systems for food irradiation, solid-state devices for real-time and passive dosimetry over wide dose-rate and dose ranges, and improved analytical instruments and data acquisition. (author)

  20. Sulfonation of vulcanized ethylene-propylene-diene terpolymer membranes

    International Nuclear Information System (INIS)

    Barroso-Bujans, F.; Verdejo, R.; Lozano, A.; Fierro, J.L.G.; Lopez-Manchado, M.A.

    2008-01-01

    In the present work, sulfonation of previously vulcanized ethylene propylene diene terpolymer (EPDM) membranes was developed in a swelling solvent with acetyl sulfate. This procedure avoids the need to pre-dissolve the raw polymer. The reaction conditions were optimized in terms of solvent type, reaction time, acetyl sulfate concentration and film thickness to obtain the maximum degree of sulfonation of the polymer. The sulfonation procedure presented in this study yields a degree of sulfonation comparable to the chlorosulfonic acid procedure. Sulfonic acid groups were detected by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy, and quantified by titrations. Proton conductivity and water uptake were measured by means of impedance spectroscopy and swelling measurements, respectively, and were correlated with the degree of sulfonation. Tensile strength and Young's modulus of sulfonated EPDM increased with the degree of sulfonation, while elongation at break remained constant. Thermal stability of the sulfonated EPDM was studied by simultaneous thermogravimetry-mass spectroscopy

  1. Radiation in industrial processes

    International Nuclear Information System (INIS)

    1959-01-01

    The uses of ionizing radiation can be divided into two broad categories. First, it can be used as a tool of investigation, measurement and testing, and secondly, it can be a direct agent in inducing chemical processes. For example, radiation can help in the detecting and locating of malignant tumours, and it can be employed also for the destruction of those tumours. Again, it can reveal intricate processes of plant growth and, at the same time, can initiate certain processes which result in the growth of new varieties of plants. Similarly in industry, radiation is both a tool of detection, testing and measurement and an active agent for the initiation of useful chemical reactions. The initiation of chemical reactions usually requires larger and more powerful sources of radiation. Such radiation can be provided by substances like cobalt 60 and caesium 137 or by machines which accelerate nuclear particles to very high energies. Of the particle-accelerating machines, the most useful in this field are those which accelerate electrons to energies considerably higher than those possessed by the electrons (beta particles) emitted by radioactive substances. These high-energy radiations produce interesting reactions both in organic life and in materials for industry. Several of the papers presented at the Warsaw conference were devoted to the application of ionizing radiation to polymerization and other useful reactions in the manufacture and treatment of plastics. The polymerization of the ethylene series of hydro-carbons was discussed from various angles and the technical characteristics and requirements were described. It was pointed out by some experts that the cross-linking effect of radiation resulted in a superior product, opening the way to new applications of polyethylene. Irradiated polyethylene film has been sold for several years, and electrical wire has been made with irradiated polyethylene as the insulating jacket. Other reactions discussed included the cross

  2. Radiation processed polysaccharide products

    International Nuclear Information System (INIS)

    Nguyen, Quoc Hien

    2007-01-01

    Radiation crosslinking, degradation and grafting techniques for modification of polymeric materials including natural polysaccharides have been providing many unique products. In this communication, typical products from radiation processed polysaccharides particularly plant growth promoter from alginate, plant protector and elicitor from chitosan, super water absorbent containing starch, hydrogel sheet containing carrageenan/CM-chitosan as burn wound dressing, metal ion adsorbent from partially deacetylated chitin were described. The procedures for producing those above products were also outlined. Future development works on radiation processing of polysaccharides were briefly presented. (author)

  3. Preparation and evaluation of some investigated natural and acrylonitrile rubber vulcanizations for physiotherapeutic purposes

    International Nuclear Information System (INIS)

    Helaly, F.M; El-Sawy, S.M.

    2005-01-01

    A trial was made to design and prepare rubber article that can be used to reactivate, strengthen and reinforce the hand muscles and fingers which had suffered from trouble movement.The investigated rubber article was prepared from natural and acrylonitrile rubber formulations. These formulations were processed in the form of compounds which contain significant quantities of fillers as Hisil, CaCO 3 and TiO 2 .The rheological characteristics and physicochemical properties of the vulcanizations were determined according to standard tests. It was found that it is possible to prepare the designated rubber article for the desired purpose. The test results show that the prepared rubber article has a good chemical resistant against acid, alkali, and salt. Also it possesses high resistance to deterioration and deformation. The prepared article has an ability to retain its elastic property after the action of compressive forces at 70 degree C for 24 hours.This was conformed with applied commercial hand exercise therapeutic article

  4. Radiation processing and sterilization

    International Nuclear Information System (INIS)

    Takehisa, M.; Machi, S.

    1987-01-01

    This growth of commercial radiation processing has been largely dependent on the achievement in production of reliable and less expensive radiation facilities as well as the research and development effort for new applications. Although world statistics of the growth are not available, Figure 20-1 shows steady growth in the number of EBAs installed in Japan for various purposes. Growth rate of Co-60 sources supplied by AECL (Atomic Energy of Canada Limited), which supplied approximately 80% of the world market, approximately 10% per year, including future growth estimates. Potential applications of radiation processing under development are in environmental conservation (e.g., treatment of sewage sludge, waste water, and exhaust gases) and bioengineering (e.g., immobilization of bioactive materials). The authors plan to introduce her the characteristics of radiation processing, examples of its industrial applications, the status of its research and development activities, and an economic analysis

  5. Highly toughened polypropylene/ethylene–propylene-diene monomer/zinc dimethacrylate ternary blends prepared via peroxide-induced dynamic vulcanization

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yukun, E-mail: cyk@scut.edu.cn [The Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou 510640 (China); School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640 (China); Xu, Chuanhui [College of Material Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Cao, Liming [The Key Laboratory of Polymer Processing Engineering, Ministry of Education, South China University of Technology, Guangzhou 510640 (China); School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640 (China); Cao, Xiaodong [College of Material Science and Engineering, South China University of Technology, Guangzhou 510640 (China)

    2013-02-15

    Polypropylene (PP)/ethylene–propylene-diene monomer (EPDM)/zinc dimethacrylate (ZDMA) blends with remarkable toughness and extensibility were successfully prepared via peroxide dynamical vulcanization. A unique structure with the EPDM particles surrounded by a transition zone containing numerous polymerized ZDMA (PZDMA) nano-particles was observed for the first time by using transmission electron microscopy (TEM) examination, which contributed to the dramatically increase of Izod impact strength. Dynamic mechanical analysis (DMA) confirmed that the possible PZDMA graft products resulted from peroxide dynamical vulcanization improved the compatibility between EPDM and PP phases. The specific morphology of the PP/EPDM/ZDMA blends indicated that ZDMA can lead to size reduction and good distribution uniformity of the crosslinked rubber particles and the increase of adhesion between PP matrix and EPDM phases during deformation. The synergic effect of the increase in the effective volume of the EPDM phase, the improved compatibility and adhesion between EPDM and PP phases and the deformation of those fine rubber particles is believed to result in the remarkable high toughness and extensibility of the PP/EPDM/ZDMA blends. Particularly for the PP/EPDM ratio of 70/30, the PP/EPDM/ZDMA (70/30/9, w/w/w) ternary blends with the Izod impact strength nearly 2 times higher than PP/EPDM (70/30, w/w) binary blends and 15–20 times higher than PP are achieved; besides, the elongation at break of PP/EPDM/ZDMA ternary blends is 4–5 times higher than that of PP/EPDM binary blends. - Highlights: ► ZDMA largely toughen peroxide dynamically vulcanized PP/EPDM blend. ► PZDMA graft products improved the compatibility and adhesion between EPDM and PP. ► Size reduction and good distribution uniformity of crosslinked rubber particles.

  6. Highly toughened polypropylene/ethylene–propylene-diene monomer/zinc dimethacrylate ternary blends prepared via peroxide-induced dynamic vulcanization

    International Nuclear Information System (INIS)

    Chen, Yukun; Xu, Chuanhui; Cao, Liming; Cao, Xiaodong

    2013-01-01

    Polypropylene (PP)/ethylene–propylene-diene monomer (EPDM)/zinc dimethacrylate (ZDMA) blends with remarkable toughness and extensibility were successfully prepared via peroxide dynamical vulcanization. A unique structure with the EPDM particles surrounded by a transition zone containing numerous polymerized ZDMA (PZDMA) nano-particles was observed for the first time by using transmission electron microscopy (TEM) examination, which contributed to the dramatically increase of Izod impact strength. Dynamic mechanical analysis (DMA) confirmed that the possible PZDMA graft products resulted from peroxide dynamical vulcanization improved the compatibility between EPDM and PP phases. The specific morphology of the PP/EPDM/ZDMA blends indicated that ZDMA can lead to size reduction and good distribution uniformity of the crosslinked rubber particles and the increase of adhesion between PP matrix and EPDM phases during deformation. The synergic effect of the increase in the effective volume of the EPDM phase, the improved compatibility and adhesion between EPDM and PP phases and the deformation of those fine rubber particles is believed to result in the remarkable high toughness and extensibility of the PP/EPDM/ZDMA blends. Particularly for the PP/EPDM ratio of 70/30, the PP/EPDM/ZDMA (70/30/9, w/w/w) ternary blends with the Izod impact strength nearly 2 times higher than PP/EPDM (70/30, w/w) binary blends and 15–20 times higher than PP are achieved; besides, the elongation at break of PP/EPDM/ZDMA ternary blends is 4–5 times higher than that of PP/EPDM binary blends. - Highlights: ► ZDMA largely toughen peroxide dynamically vulcanized PP/EPDM blend. ► PZDMA graft products improved the compatibility and adhesion between EPDM and PP. ► Size reduction and good distribution uniformity of crosslinked rubber particles

  7. Syntheses, spectroscopic characterization, crystal structure and natural rubber vulcanization activity of new disulfides derived from sulfonyldithiocarbimates

    Science.gov (United States)

    Alves, Leandro de Carvalho; Rubinger, Mayura Marques Magalhães; Tavares, Eder do Couto; Janczak, Jan; Pacheco, Elen Beatriz Acordi Vasques; Visconte, Leila Lea Yuan; Oliveira, Marcelo Ribeiro Leite

    2013-09-01

    The compounds (Bu4N)2[(4-RC6H4SO2NCS2)2] [Bu4N = tetrabutylammonium cation; R = H (1), F (2), Cl (3) and Br (4)] and (Ph4P)2[(4-RC6H4SO2NCS2)2]ṡH2O [Ph4P = tetraphenylphosphonium cation and R = I (5)] were synthesized by the reaction of the potassium dithiocarbimates (4-RC6H4SO2NCS2K2ṡ2H2O) with I2 and Bu4NBr or Ph4PCl. The IR data were consistent with the formation of the dithiocarbimatodisulfides anions. The NMR spectra showed the expected signals for the cations and anions in a 2:1 proportion. The structures of compounds 1-5 were determined by the single crystal X-ray diffraction. The compounds 2, 3 and 4 are isostructural and crystallise in the centrosymmetric space group C2/c of the monoclinic system. Compound 1 crystallises in the monoclinic system in the space group of P21/n and the compound 5 crystallises in the centrosymmetric space group P-1 of the triclinic system. The complex anions of compounds 2, 3 and 4 exhibit similar conformations having twofold symmetry, while in 1 and 5 the anions exhibit C1 symmetry. The activity of the new compounds in the vulcanization of the natural rubber was evaluated and compared to the commercial accelerators ZDMC, TBBS and TMTD. These studies confirm that the sulfonyldithiocarbimato disulfides anions are new vulcanization accelerators, being slower than the commercial accelerators, but producing a greater degree of crosslinking, and scorch time values compatible with good processing safety for industrial applications. The mechanical properties, stress and tear resistances were determined and compared to those obtained with the commercial accelerators.

  8. Introduction to radiation processing

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    2008-01-01

    Nuclear technology such as γ-rays, electron beams and ion beams irradiation is widely used in industrial, medical and agricultural fields. The purpose of radiation application is aiming at increasing welfare and quality of our life. Radiation technology applied to medical care is widely known as X-ray diagnosis but the contribution of radiation processing to our daily life is not well known even though it is effectively used in industry and agriculture. The main radiation processing in industry is the modification of polymers, i.e. heat shrinkable tube, radial tire, plastic foam, etc. in a car, heat resistant wire and cable, semiconductor, floppy disk, etc. in a computer, and sterilization of medical devices. In Agriculture, radiation has been used in various fields such as food irradiation, sterile insect technique, mutation breeding, etc. contributing for human being to supply foods and sustainable environment. (author)

  9. Selective Deuteron Acceleration and Neutron Production on the Vulcan PW Laser

    Science.gov (United States)

    Krygier, A. G.; Morrison, J. T.; Freeman, R. R.; Ahmed, H.; Green, J. A.; Alejo, A.; Kar, S.; Vassura, L.

    2014-10-01

    Fast neutron sources are important for a variety of applications including radiography and the detection of sensitive materials. Here we report on the results of an experiment using the Vulcan PW laser at Rutherford Appleton Laboratory to produce a nearly pure deuterium ion beam via Target Normal Sheath Acceleration. The typical contaminants are suppressed by freezing a μ m's thick layer of heavy water vapor (D2 O) onto a cryogenic target during the shot sequence. Neutrons were generated by colliding the accelerated deuterons were into secondary targets made of deuterated plastic in the pitcher-catcher arrangement. Absolute yields for deuterium ions and neutrons are reported. This work is supported by DOE Contract DE-FC02-04ER54789.

  10. New infrared transmitting material via inverse vulcanization of elemental sulfur to prepare high refractive index polymers.

    Science.gov (United States)

    Griebel, Jared J; Namnabat, Soha; Kim, Eui Tae; Himmelhuber, Roland; Moronta, Dominic H; Chung, Woo Jin; Simmonds, Adam G; Kim, Kyung-Jo; van der Laan, John; Nguyen, Ngoc A; Dereniak, Eustace L; Mackay, Michael E; Char, Kookheon; Glass, Richard S; Norwood, Robert A; Pyun, Jeffrey

    2014-05-21

    Polymers for IR imaging: The preparation of high refractive index polymers (n = 1.75 to 1.86) via the inverse vulcanization of elemental sulfur is reported. High quality imaging in the near (1.5 μm) and mid-IR (3-5 μm) regions using high refractive index polymeric lenses from these sulfur materials was demonstrated. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. The VULCAN Project: Toward a better understanding of the vulnerability of soil organic matter to climate change in permafrost ecosystems

    Science.gov (United States)

    Plaza, C.; Schuur, E.; Maestre, F. T.

    2015-12-01

    Despite much recent research, high uncertainty persists concerning the extent to which global warming influences the rate of permafrost soil organic matter loss and how this affects the functioning of permafrost ecosystems and the net transfer of C to the atmosphere. This uncertainty continues, at least in part, because the processes that protect soil organic matter from decomposition and stabilize fresh plant-derived organic materials entering the soil are largely unknown. The objective of the VULCAN (VULnerability of soil organic CArboN to climate change in permafrost and dryland ecosystems) project is to gain a deeper insight into these processes, especially at the molecular level, and to explore potential implications in terms of permafrost ecosystem functioning and feedback to climate change. We will capitalize on a globally unique ecosystem warming experiment in Alaska, the C in Permafrost Experimental Heating Research (CiPEHR) project, which is monitoring soil temperature and moisture, thaw depth, water table depth, plant productivity, phenology, and nutrient status, and soil CO2 and CH4 fluxes. Soil samples have been collected from the CiPEHR experiment from strategic depths, depending on thaw depth, and allow us to examine effects related to freeze/thaw, waterlogging, and organic matter relocation along the soil profile. We will use physical fractionation methods to separate soil organic matter pools characterized by different preservation mechanisms of aggregation and mineral interaction. We will determine organic C and total N content, transformation rates, turnovers, ages, and structural composition of soil organic matter fractions by elemental analysis, stable and radioactive isotope techniques, and nuclear magnetic resonance tools. Acknowledgements: This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 654132. Web site: http://vulcan.comule.com

  12. Signal processing for radiation detectors

    CERN Document Server

    Nakhostin, Mohammad

    2018-01-01

    This book provides a clear understanding of the principles of signal processing of radiation detectors. It puts great emphasis on the characteristics of pulses from various types of detectors and offers a full overview on the basic concepts required to understand detector signal processing systems and pulse processing techniques. Signal Processing for Radiation Detectors covers all of the important aspects of signal processing, including energy spectroscopy, timing measurements, position-sensing, pulse-shape discrimination, and radiation intensity measurement. The book encompasses a wide range of applications so that readers from different disciplines can benefit from all of the information. In addition, this resource: * Describes both analog and digital techniques of signal processing * Presents a complete compilation of digital pulse processing algorithms * Extrapolates content from more than 700 references covering classic papers as well as those of today * Demonstrates concepts with more than 340 origin...

  13. Radiation processing

    International Nuclear Information System (INIS)

    Noriah Mod Ali

    2005-01-01

    This chapter covers the basic principle and application of radiation technology. The topic titled specific application discussed briefly the following subtopics: 1) Polymer modification - crosslinking, polymerisation, degradation, grafting; 2) Medical sterilisation; 3) Food irradiation; 4) Environmental protection - waste processing, pollutants treatment

  14. Radiation processing: a versatile technology for industry

    International Nuclear Information System (INIS)

    Cabalfin, E.G.

    1996-01-01

    Soon after the discovery of x-ray in 1895 and radioactivity in 1896, it was recognized that ionizing radiation can modify the chemical, physical and/or biological properties of materials. However, it was only in the late 50's, when large radiation sources become available, has this unique property of radiation found industrial applications in radiation processing. Today, radiation processing has been used by industry in such diverse applications, such as radiation sterilization/decontamination of medical products, pharmaceuticals, cosmetics and their raw materials; radiation cross-linking of wire and cable insulation; production of heat shrinkable materials and polymer foam; and radiation curing of coatings, adhesives and inks on a wide variety of substrates. In addition to being a clean environment-friendly technology, radiation processing can also be used for the conservation of the environment by such processes as radiation treatment of flue gases to remove SO 2 and NO x and disinfection of sewage sludge. Because of the many advantages offered by radiation processing, industry is showing strong interest in the technology as evidenced by the growing number of industrial radiation facilities in many countries. (author)

  15. Radiation signal processing system

    International Nuclear Information System (INIS)

    Bennett, M.; Knoll, G.; Strange, D.

    1980-01-01

    An improved signal processing system for radiation imaging apparatus comprises: a radiation transducer producing transducer signals proportional to apparent spatial coordinates of detected radiation events; means for storing true spatial coordinates corresponding to a plurality of predetermined apparent spatial coordinates relative to selected detected radiation events said means for storing responsive to said transducer signal and producing an output signal representative of said true spatial coordinates; and means for interpolating the true spatial coordinates of the detected radiation events located intermediate the stored true spatial coordinates, said means for interpolating communicating with said means for storing

  16. Electrochemical characterization of adsorbed bilirubin oxidase on Vulcan XC 72R for the biocathode preparation in a glucose/O2 biofuel cell

    International Nuclear Information System (INIS)

    Habrioux, A.; Napporn, T.; Servat, K.; Tingry, S.; Kokoh, K.B.

    2010-01-01

    A new biocathode was built and tested. It consisted of bilirubin oxidase adsorbed on Vulcan XC 72 R and immobilized into a Nafion matrix. The possibility of direct electron transfer between bilirubin oxidase and Vulcan XC 72 R was also demonstrated. The kinetics on biocathode were enhanced by including 2,2'-azinobis-3-ethylbenzothiazoline-5-sulfonic acid in the catalytic film. A first order reaction rate was observed for oxygen concentrations lower than 22%. A complete kinetic investigation of the system was shown. A biofuel cell test performed with this biocathode and Au 70 Pt 30 nanoparticles as anode catalyst permitted to reach a power density of 170 μW cm -2 at a cell voltage of 0.6 V, which is superior to what can be obtained with the concentric design.

  17. Thermal effects in radiation processing

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1985-01-01

    The balance of ionizing radiation energy incident on an object being processed is discussed in terms of energy losses, influencing the amount really absorbed. To obtain the amount of heat produced, the absorbed energy is corrected for the change in internal energy of the system and for the heat effect of secondary reactions developing after the initiation. The temperature of a processed object results from the heat evolved and from the specific heat of the material comprising the object. The csub(p) of most materials is usually much lower than that of aqueous systems and therefore temperatures after irradiation are higher. The role of low specific heat in radiation processing at cryogenic conditions is stressed. Adiabatic conditions of accelerator irradiation are contrasted with the steady state thermal conditions prevailing in large gamma sources. Among specific questions discussed in the last part of the paper are: intermediate and final temperature of composite materials, measurement of real thermal effects in situ, neutralization of undesired warming experienced during radiation processing, processing at temperatures other than ambient and administration of very high doses of radiation. (author)

  18. Thermal effects in radiation processing

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1984-01-01

    The balance of ionizing radiation energy incident on an object being processed is discussed in terms of energy losses, influencing the amount really absorbed. To obtain the amount of heat produced, the absorbed energy is corrected for the change in internal energy of the system and for the heat effect of secondary reactions developing after the initiation. The temperature of a processed object results from the heat evolved and from the specific heat of the material comprising the object. The specific heat of most materials is usually much lower than that of aqueous systems and therefore temperatures after irradiation are higher. The role of low specific heat in radiation processing at cryogenic conditions is stressed. Adiabatic conditions of accelerator irradiation are contrasted with the steady state thermal conditions prevailing in large gamma sources. Among specific questions discussed in the last part of the paper are: intermediate and final temperature of composite materials, measurement of real thermal effects in situ, neutralization of undesired warming experienced during radiation processing, processing at temperatures other than ambient and administration of very high doses of radiation

  19. Status of radiation processing: Indian scenario

    International Nuclear Information System (INIS)

    Niyogi, U.K.

    2013-01-01

    Radiation processing is a technique to process different types of materials by way of providing radiations of different energies for various applications. Depending upon the changes, one needs to select the radiations of appropriate energy. The well established mechanism behind the changes occurring in the material is the excitation of electrons in the molecules and atoms. It is a proven technology for more than five decades which results in the modification in materials, both at the bulk and surface levels. While radiations such as IR and UV have low energy and hence affect the surface of the material only, highly energetic radiations such as gamma and e-beam are useful to modify the material at the bulk level. Radiation processing is the most efficient technique for polymerization, sterilization, disinfestations, etc. which are applied in industries such as wires and cables, healthcare, food processing, pet/animal feed, herbal and ayurvedic, artificial jewellery, etc.

  20. Neutron Production from In-situ Heavy Ice Coated Targets at Vulcan

    Science.gov (United States)

    Morrison, John; Krygier, A. G.; Kar, S.; Ahmed, H.; Alejo, A.; Clarke, R.; Fuchs, J.; Green, A.; Jung, D.; Kleinschmidt, A.; Najmudin, Z.; Nakamura, H.; Norreys, P.; Notley, M.; Oliver, M.; Roth, M.; Vassura, L.; Zepf, M.; Borghesi, M.; Freeman, R. R.

    2015-05-01

    Laser based neutron production experiments have been performed utilizing ultra-high intensity laser accelerated ions impinging upon a secondary target. The neutron yield from such experiments may be improved if the accelerated ions were primarily deuterons taking advantage of the d-d cross section. Recent experiments have demonstrated that selective deuteron acceleration from in-situ heavy ice coating of targets can produce ion spectra where deuterons comprise > 99 % of the measured ions. Results will be presented from integrated neutron production experiments from heavy ice targets coated in-situ recently performed on the Vulcan laser at Rutherford Appleton Laboratory. We are grateful for the Staff at RAL and acknowledge funding from the US DoE. AFOSR, European Social Fund, and the Czech Republic.

  1. Improved properties of dissimilar rubber-rubber blends using plasma polymer encapsulated curatives : a novel surface modification method to improve co-vulcanization

    NARCIS (Netherlands)

    Guo, R.

    2009-01-01

    In industrial applications, different rubber types are often blended to fine-tune or optimize the property portfolio required for successful performance of articles. Considering the complexity of a rubber blend compound, wherein numerous additives are involved, vulcanization or cure mismatch often

  2. Gamma irradiators for radiation processing

    International Nuclear Information System (INIS)

    2006-01-01

    Radiation technology is one of the most important fields which the IAEA supports and promotes, and has several programmes that facilitate its use in the developing Member States. In view of this mandate, this Booklet on 'Gamma Irradiators for Radiation Processing' is prepared which describes variety of gamma irradiators that can be used for radiation processing applications. It is intended to present description of general principles of design and operation of the gamma irradiators available currently for industrial use. It aims at providing information to industrial end users to familiarise them with the technology, with the hope that the information contained here would assist them in selecting the most optimum irradiator for their needs. Correct selection affects not only the ease of operation but also yields higher efficiency, and thus improved economy. The Booklet is also intended for promoting radiation processing in general to governments and general public

  3. Industrial processing with radiation

    International Nuclear Information System (INIS)

    Du Plessis, T.A.

    1976-01-01

    The use of large isotopic radiation sources and accelerators in industry is reviewed. The advantages of various sources of ionizing radiation are indicated, and the development and present status of radiation technology are briefly described. Attention is given to the role played by radiation processing in the cross-linking of polymers as applied to cable insulation, artificial limbs and packaging materials, as well as for improving natural rubber. In addition, attention is given to radiation as a possible means of synthesizing polymers, of hardening non-conventional coatings and of manufacturing polymer-wood composites, thereby improving the properties of softwoods. The possibility of improving natural fibres by means of radiation is discussed, and attention is given to the important role already played by radiation in the sterilization of medical products. Finally, reference is made to the role which radiation can play in reducing food spoilage, as well as in making sewage sludge suitable for agricultural purposes [af

  4. Nuclear science in the 20th century. Radiation chemistry and radiation processing

    International Nuclear Information System (INIS)

    Fu Tao; Xu Furong; Zheng Chunkai

    2003-01-01

    The application of nuclear science and technology to chemistry has led to two important subjects, radiation chemistry and radiation processing, which are playing important roles in many aspects of science and society. We review the development and major applications of radiation chemistry and radiation processing, including the basic physical and chemical mechanisms involved

  5. Radiation processing of wood-plastic composites

    International Nuclear Information System (INIS)

    Czvikovszky, T.

    1992-01-01

    There are three main types of radiation-processed composite material derived from plastics and fibrous natural polymers. The first are the monomer-impregnated, radiation-treated wood-plastic composites (WPC). They became a commercial success in the early 1970s. More recently, work has focused on improving the WPCs by creating in them interpenetrating network (IPN) systems by the use of appropriate multifunctional oligomers and monomers. The main kinetic features of radiation-initiated chain polymerization remain applicable even in impregnated wood. The second type are the plastics filled or reinforced with dispersed wood fiber or other cellulosics (WFRP). In their case, radiation processing offers a new opportunity to apply radiation-reactive adhesion promoters between wood or cellulosic fibers and the thermoplastic matrices. The third type are the laminar composites made by electron beam coating of wood-based agglomerate sheets and boards. This chapter reviews the industrial applications and the radiation processing of the three types of the wood-plastic composites and indicates future trends. (orig.)

  6. Advances in radiation processing of polymeric materials

    International Nuclear Information System (INIS)

    Makuuchi, K.; Sasak, T.; Vikis, A.C.; Singh, A.

    1993-12-01

    In this paper we review recent advances in industrial applications of electron-beam irradiation in the field of polymer processing at the Takasaki Radiation Chemistry Research Establishment (TRCRE) of JAERI (Japan Atomic Energy Research Institute), and the Whiteshell Laboratories of AECL Research, Canada. Irradiation of a substrate with ionizing radiation produces free radicals through ionization and excitation events. The subsequent chemistry of these radicals is used in radiation processing as a substitute for conventional processing techniques based on heating and/or the addition of chemicals. The advantages of radiation processing include the formation of novel products with desirable material properties, favourable overall process economics and, often, environmental benefits

  7. Oscillator and system development on the VULCAN glass laser system for the plasma beat-wave program

    International Nuclear Information System (INIS)

    Danson, C.N.

    1990-03-01

    This thesis describes the oscillator and system development on the VULCAN glass laser undertaken in support of the RAL Plasma Beat-wave experiments. This program seeks to evaluate advanced particle acceleration schemes for a new generation of machines for fundamental research in high energy physics. The experiments required two synchronised high power laser pulses of slightly different wavelength. These pulses were generated using two different laser media; Nd:YAG and Nd:YLF operating at 1.064 and 1.053 microns respectively. The first oscillator system developed operated with both lasing media housed in the same laser cavity. Problems with the stability of the optical output required the development of a second system which housed the two lasing media in separate cavities. The second aspect of the development work, described in this thesis, was the reconfiguration of the VULCAN glass laser system to amplify the two laser pulses to power levels of 0.5 TW per pulse. The first scheduled experiment required the two pulses to be propagated co-linearly. To amplify the pulses to the high output powers required two amplifying media to be used which preferentially amplify the two lasing wavelengths. For the later experiments the two laser pulses were amplified in separate amplifier chains which required the design of an efficient beam combiner. (author)

  8. Radiation processing of natural polymer

    International Nuclear Information System (INIS)

    Khairul Zaman; Kamaruddin Hashim; Zulkafli Ghazali; Mohd Hilmi Mahmood; Jamaliah Sharif

    2006-01-01

    Radiation processing of natural polymer has been the subject of interest of countries in this region in the past 5 ∼ 7 years. Although some of the output of the research have been commercialized in particular for the applications in the agriculture and healthcare sectors, the potential applications of radiation processing of natural polymers in the medical sector are yet to be fully understood and developed. (author)

  9. Trend and future of radiation processing of polymers

    International Nuclear Information System (INIS)

    Makuuchi, Keizo

    2000-01-01

    Five Asian countries have been cooperating with Takasaki Radiation Chemistry Research Establishment (TRCRE), Japan, in the field of radiation processing of polymers. The experience of cooperation is summarized. Main processes are polymerization of monomers, cross-linking and degradation of polymers, graft polymerization and curing. The industrial state-of-art of radiation processing in Japan is described. The characteristics of radiation processes are compared with other processes. The future prospect of processing is also described. The growth in cross-linking and degradation are anticipated, whereas graft polymerization and curing are to confront to severe competition with other methods. The possibility of developing new area of radiation processing in Asian counties is pointed out. (A. Yamamoto)

  10. Influence of the Synthesis Method for Pt Catalysts Supported on Highly Mesoporous Carbon Xerogel and Vulcan Carbon Black on the Electro-Oxidation of Methanol

    Directory of Open Access Journals (Sweden)

    Cinthia Alegre

    2015-03-01

    Full Text Available Platinum catalysts supported on carbon xerogel and carbon black (Vulcan were synthesized with the aim of investigating the influence of the characteristics of the support on the electrochemical performance of the catalysts. Three synthesis methods were compared: an impregnation method with two different reducing agents, sodium borohydride and formic acid, and a microemulsion method, in order to study the effect of the synthesis method on the physico-chemical properties of the catalysts. X-ray diffraction and transmission electron microscopy were applied. Cyclic voltammetry and chronoamperometry were used for studying carbon monoxide and methanol oxidation. Catalysts supported on carbon xerogel presented higher catalytic activities towards CO and CH3OH oxidation than catalysts supported on Vulcan. The higher mesoporosity of carbon xerogel was responsible for the favored diffusion of reagents towards catalytic centers.

  11. Combined experimental and numerical kinetic characterization of NR vulcanized with sulphur, N terbutyl, 2 benzothiazylsulphenamide and N,N diphenyl guanidine

    Energy Technology Data Exchange (ETDEWEB)

    Milani, G., E-mail: gabriele.milani@polimi.it [Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Hanel, T.; Donetti, R. [Pirelli Tyre, Via Alberto e Piero Pirelli 25, 20126 Milan (Italy); Milani, F. [Chem. Co, Via J.F.Kennedy 2, 45030 Occhiobello (Italy)

    2016-06-08

    The paper presents the final results of a comprehensive experimental and numerical analysis aimed at deeply investigating the behavior of Natural Rubber (NR) vulcanized with sulphur in presence of different accelerators during standard rheometer tests. NR in presence of sulphur and two different accelerators (DPG and TBBS) in various concentrations is investigated, changing the curing temperature in the range 150-180°C and obtaining rheometer curves with a step of 10°C. Sulphur-TBBS concentrations considered are 1-1, 1-3, 3-3 and 3-1, with DPG at 1-4 phr respectively. A total of 48 experimental rheometer curves is so obtained. To fit experimental data, the general reaction scheme proposed by Han and co-workers for vulcanized sulphur NR is re-adapted and suitably modified taking into account the single contributions of the different accelerators. Chain reactions initiated by the formation of macro-compounds responsible for the formation of the unmatured crosslinked polymer are accounted for. In presence of two accelerators, reactions are assumed to proceed in parallel, making the practically effective hypothesis that there is no interaction between the two accelerators. From the simplified kinetic scheme adopted, a closed form solution is found for the crosslink density, with the only limitation that the induction period is excluded from computations. For each experimented case on the same blend, reaction kinetic constants provided by the model are utilized to deduce their trend in the Arrhenius space, also outside the temperature range inspected. Rather close linearity is found in the majority of the cases. A comparative analysis is carefully conducted among the constants at the different concentrations of S, TBBS and DPG investigated, allowing a prediction of curing behavior at any vulcanization temperature and with concentrations not experimentally tested, without the need of addition costly experimentation.

  12. Combined experimental and numerical kinetic characterization of NR vulcanized with sulphur, N terbutyl, 2 benzothiazylsulphenamide and N,N diphenyl guanidine

    International Nuclear Information System (INIS)

    Milani, G.; Hanel, T.; Donetti, R.; Milani, F.

    2016-01-01

    The paper presents the final results of a comprehensive experimental and numerical analysis aimed at deeply investigating the behavior of Natural Rubber (NR) vulcanized with sulphur in presence of different accelerators during standard rheometer tests. NR in presence of sulphur and two different accelerators (DPG and TBBS) in various concentrations is investigated, changing the curing temperature in the range 150-180°C and obtaining rheometer curves with a step of 10°C. Sulphur-TBBS concentrations considered are 1-1, 1-3, 3-3 and 3-1, with DPG at 1-4 phr respectively. A total of 48 experimental rheometer curves is so obtained. To fit experimental data, the general reaction scheme proposed by Han and co-workers for vulcanized sulphur NR is re-adapted and suitably modified taking into account the single contributions of the different accelerators. Chain reactions initiated by the formation of macro-compounds responsible for the formation of the unmatured crosslinked polymer are accounted for. In presence of two accelerators, reactions are assumed to proceed in parallel, making the practically effective hypothesis that there is no interaction between the two accelerators. From the simplified kinetic scheme adopted, a closed form solution is found for the crosslink density, with the only limitation that the induction period is excluded from computations. For each experimented case on the same blend, reaction kinetic constants provided by the model are utilized to deduce their trend in the Arrhenius space, also outside the temperature range inspected. Rather close linearity is found in the majority of the cases. A comparative analysis is carefully conducted among the constants at the different concentrations of S, TBBS and DPG investigated, allowing a prediction of curing behavior at any vulcanization temperature and with concentrations not experimentally tested, without the need of addition costly experimentation.

  13. Radiation processing in the U.S.S.R.

    Science.gov (United States)

    Pikaev, A. K.

    The present paper is a short review of the modern status of radiation processing in the U.S.S.R. Data on ionizing radiation sources used in radiation processing are reported. The main directions of the development of this field of technology: radiation modification of materials, radiation curing of coatings, radiation-chemical methods of synthesis, radiation sterilization of medical products, radiation treatment of food, application of ionizing radiation for the solution of ecological problems etc. -are considered.

  14. Ionizing Radiation Processing Technology

    International Nuclear Information System (INIS)

    Rida Tajau; Kamarudin Hashim; Jamaliah Sharif; Ratnam, C.T.; Keong, C.C.

    2017-01-01

    This book completely brief on the basic concept and theory of ionizing radiation in polymers material processing. Besides of that the basic concept of polymerization addition, cross-linking and radiation degradation also highlighted in this informative book. All of the information is from scientific writing based on comprehensive scientific research in polymerization industry which using the radiation ionizing. It is very useful to other researcher whose study in Nuclear Sciencea and Science of Chemical and Material to use this book as a guideline for them in future scientific esearch.

  15. Effect of radiation processing on meat tenderisation

    International Nuclear Information System (INIS)

    Kanatt, Sweetie R.; Chawla, S.P.; Sharma, Arun

    2015-01-01

    The effect of radiation processing (0, 2.5, 5 and 10 kGy) on the tenderness of three types of popularly consumed meat in India namely chicken, lamb and buffalo was investigated. In irradiated meat samples dose dependant reduction in water holding capacity, cooking yield and shear force was observed. Reduction in shear force upon radiation processing was more pronounced in buffalo meat. Protein and collagen solubility as well as TCA soluble protein content increased on irradiation. Radiation processing of meat samples resulted in some change in colour of meat. Results suggested that irradiation leads to dose dependant tenderization of meat. Radiation processing of meat at a dose of 2.5 kGy improved its texture and had acceptable odour. - Highlights: • Effect of radiation processing on tenderness of three meat systems was evaluated. • Dose dependant reduction in shear force seen in buffalo meat. • Collagen solubility increased with irradiation

  16. The application of radiation technology in industrial processes

    International Nuclear Information System (INIS)

    Silvermann, J.

    1974-01-01

    The author makes a general survey of current applications for radiation processing such as sterilization of biological and medical supplies, crosslinking of polymers, production of durable press fabrics, radiation-cured coating, production of wood-plastic composites, radiation degradation and chemical synthesis. The adoption of radiation processing on large scale by Western Electric is presented. The trend in costs and the environmental problems has a profound effect on the future of radiation processing. (M.S.)

  17. Some new radiation processes in plasmas

    International Nuclear Information System (INIS)

    Wu, C.S.

    1981-01-01

    Some new plasma radiation processes are reviewed, viz., (1) emission near the electron plasma frequency, (2) direct amplification of radiation near the electron cycloton frequency, and (3) parametic amplification of radiation by stimulated scattering. (L.C.) [pt

  18. The advances in radiation processing technology and some suggestion

    International Nuclear Information System (INIS)

    Wu Jilan; Wei Genshuan; Ha Hongfei

    1992-01-01

    Radiation processing technology has been made great advances in the last decade especially in the developed countries. According to the conservative evaluation, the total sales of radiation processing products approached about 2-3 billion U.S. dollar in 1981, there after, the processing capacity at least doubles. Now, the intensities of 60 Co in use for radiation processing are (5.55-7.40) x 10 18 Bq and there are about 600 sets of electron accelerators for radiation processing. The total sales of radiation processing products are supposed to be over 10 billion U.S. dollar in 1989. However, there are only several fields commercialized. In great scale, such as radiation crosslinked heat shrinkable materials, radiation crosslinked electric cables and wires, and radiation sterilization of medical articles. In China, the radiation processing technology has been developed rapidly in the past years, but the processing capacity is still lower in comparing with developed countries. We suggest that much attention should be devoted to the training of the workers, technicians and managers. The basic theoretical and new technological researches are the keys for developing radiation processing technology at high speed in our country

  19. Applications of Radiation Processing in Industry

    International Nuclear Information System (INIS)

    Abad, Lucille V.

    2015-01-01

    Radiation processing has long been known as commercially viable technology that can be beneficially used to enhance the characteristics of many materials. Several gamma irradiators and electron beam accelerators are operating worldwide which are utilized for various established industrial applications. These could be used for the following processes: a) radiation crosslinking e.g. crosslinking of wires and cables, heat shrinkable film and tube productions, manufacture of plastic bags and tubings for medical products, pre-curing of automobile tire components, curing of polymeric coatings, etc. b) radiation degradation e.g. Scrap Teflon (Polytetraflouroethylene) to form powders, disinfestations and pasteurization of agricultural products, sterilization of medical products, etc.; and c) radiation grafting e.g. grafted non-woven fabrics for metal adsorbent. Emerging applications for radiation processing include grafted membranes for fuel cell, electrodes, cell sheet for tissue engineering, nanoparticle production, polymer composite synthesis, and fibrous catalyst for biodiesel production. Current researches at the Philippine Nuclear Research Institute consist of crosslinking of natural and synthetic polymers for medical application e.g. wound dressing, hemostats, and bioimplants for vesicouretal reflux (VUR); grafting of natural and synthetic fabrics for metal adsorbents; and radiation degradation of carrageenan as plant growth promoter. (author)

  20. The place of radiation processing in polymer technology

    International Nuclear Information System (INIS)

    Du Plessis, T.A.

    1978-01-01

    A number of polymerisation processes initiated through radiation are discussed, among others the impregnation of wood with a monomer to form wood-polymer composites; radiation crosslinking of cable insulation; radiation degradation; radiation grafting of wool and textiles; and radiation sterilization of medical and pharmaceutical equipment. The last-named process is briefly compared to steam and to ethylene oxide sterlization

  1. Radiation processing and market economy

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1998-01-01

    In the system of totalitarian economy, regulated by bureaucracy, the real value of equipment, materials and services is almost completely unknown, what makes impossible the comparison of different technologies, eliminates competition, disturbs research and development. With introduction of market economy in Central and Eastern Europe, the radiation processing has lost doubtful support, becoming an independent business, subject to laws of free market economy. Only the most valuable objects of processing have survived that test. At the top of the list are: radiation sterilization of medical equipment and radiation induced crosslinking of polymers, polyethylene in particular. New elements of competition has entered the scene, as well as questions of international regulations and standards have appeared

  2. Study of rheological, viscoelastic and vulcanization behavior of sponge EPDM/NR blended nano- composites

    International Nuclear Information System (INIS)

    Bashir, M Arshad; Shahid, M; Ahmed, Riaz; Yahya, A G

    2014-01-01

    In this research paper the effect of blending ratio of natural rubber (NR) with Ethylene Propylene Diene Monomer (EPDM) were investigated. Different samples of EPDM/NR ratio were prepared to study the variation of NR in EPDM on rheology, curing characteristics, tangent δ, and viscosity variation during vulcanization of sponge nano composites.The main aim of present research is to develop elastomeric based sponge composites with the blending ratio of base elastomers along with the carbon nano particles for high energy absorbing and damping applications. The curing characteristics, rheology and viscoelastic nature of the composite is remarkably influenced with the progressive blending ratio of the base elastomeric matrix

  3. Study of rheological, viscoelastic and vulcanization behavior of sponge EPDM/NR blended nano-composites

    International Nuclear Information System (INIS)

    Bashir, M. A.; Shahid, M.; Ahmed, R.; Yahya, A. G.

    2013-01-01

    In this research paper the effect of blending ratio of natural rubber (NR) with Ethylene Propylene Diene Monomer (EPDM) were investigated. Different samples of EPDM/NR ratio were prepared to study the variation of NR in EPDM on rheology, curing characteristics, tangent d, and viscosity variation during vulcanization of sponge nano composites. The main aim of present research is to develop elastomeric based sponge composites with the blending ratio of base elastomers along with the carbon nano particles for high energy absorbing and damping applications. The curing characteristics, rheology and viscoelastic nature of the composite is remarkably influenced with the progressive blending ratio of the base elastomeric matrix. (author)

  4. Preliminary radiation-oxidizing treatment influence on radiation-catalytic activity of zirconium during water decomposition process

    International Nuclear Information System (INIS)

    Garibov, A.A.; Aliyev, A.G.; Agayev, T.N.; Aliyev, S.M.; Velibekova, G.Z.

    2004-01-01

    The study of physical-chemical processes proceeding in contact of metal constructional materials nuclear reactors with water at simultaneous influence of temperature and radiation represents the large interest at the decision of problems material authority and safety of work of nuclear -power installations [1-2]. One of the widely widespread materials of active zone nuclear reactors is metal zirconium and its alloys. The influence of preliminary radiation processing on radiation, radiation -thermal and thermal processes of accumulation of molecular hydrogen and oxidation zirconium in contact with water is investigated at T=673 K and ρ=5mg/sm 3 [3-4]. Initial samples zirconium previously has been exposed by an irradiation in medium H 2 O 2 at D=20-410 kGy. The contribution of radiation processes in these contacts in process thermo-radiation decomposition of water and oxidation of materials of zirconium is revealed. It is established that the interaction of Zr metal, preliminary treated by radiation, with water at radiation -heterogeneous processes leads to passivity of a surface. The rate meanings of thermal, radiation -thermal processes and radiation-chemical yields of hydrogen are determined. It is revealed, that at radiation-heterogeneous processes in system Zr +H 2 O (ρ =5mg/sm 3 T=673 K) the increase of the absorbed doze up to 123 kGy results to reduction of a radiation -chemical yield of molecular hydrogen. The further increase of the absorbed doze results to increase of a radiation -chemical yield of hydrogen. The observable effect at the preliminary radiation of zirconium is connected to formation of oxide phase on a surface. The mechanism of radiation -heterogeneous processes proceeding in system Zr+H 2 O is suggested. (author)

  5. Transition radiation in EELS and cathodoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Stöger-Pollach, Michael, E-mail: stoeger@ustem.tuwien.ac.at; Kachtík, Lukáš; Miesenberger, Bernhard; Retzl, Philipp

    2017-02-15

    The excitation probability of transition radiation is measured for varying beam energies in a transmission electron microscope once using optical spectrometry of the emitted light and second using electron energy loss spectrometry. In both cases similar results are found being in good agreement with theory. The knowledge about this probability enables us to judge whether or not transition radiation has to be considered in EELS and CL data interpretation. Additionally it is shown that the emission of transition radiation happens at the sample surfaces only, when the electron passes the vacuum/sample interface and thus feeling the change of its dielectric environment. We demonstrate that in the case of aluminum the influence of transition radiation on the low loss EELS spectrum is only minor and conclude that it might be negligible for many other materials. - Highlights: • We determine the probability for the excitation of transition radiation at a large variety of beam energies in TEM. • We use a GATAN VULCAN system for optical spectrometry in the TEM. • We do angular resolved EELS experiments in a standard TEM with an angular resolution of 7.57 μrad.

  6. Effect of radiation processing on meat tenderisation

    Science.gov (United States)

    Kanatt, Sweetie R.; Chawla, S. P.; Sharma, Arun

    2015-06-01

    The effect of radiation processing (0, 2.5, 5 and 10 kGy) on the tenderness of three types of popularly consumed meat in India namely chicken, lamb and buffalo was investigated. In irradiated meat samples dose dependant reduction in water holding capacity, cooking yield and shear force was observed. Reduction in shear force upon radiation processing was more pronounced in buffalo meat. Protein and collagen solubility as well as TCA soluble protein content increased on irradiation. Radiation processing of meat samples resulted in some change in colour of meat. Results suggested that irradiation leads to dose dependant tenderization of meat. Radiation processing of meat at a dose of 2.5 kGy improved its texture and had acceptable odour.

  7. Radiation processing of polyolefins and compounds

    International Nuclear Information System (INIS)

    Barlow, A.; Biggs, J.; Maringer, M.

    1977-01-01

    Many properties of polyethylene and its copolymers are enhanced by crosslinking. This can be accomplished through the use of either peroxides or radiation. Crosslinking with peroxides is performed at elevated temperatures generally under pressure; catalyst residues remain in the product which have an adverse effect on electrical and possibly other properties. Radiation crosslinking, on the other hand, is performed under ambient conditions, is essentially free of pollution and offers lower overall production costs due to increased processing speed. A cost analysis of the two crosslinking processes applied to wire and cable coating is included. The advantages of radiation curing can be negated by processing problems which lead to inadequate product properties. Problems are described which may be encountered in developing a flame retardant, radiation curable compound for wire and cable coating. Of particular concern is the generation of a microporous structure which is accentuated by the presence of flame retardant ingredients and the absence of pressure inherent to the peroxide curing process. The procedures involved in solving these problems are briefly described. (author)

  8. Advances in ''radiation processing''. Repeat of a symposium

    International Nuclear Information System (INIS)

    Drawe, H.

    1984-01-01

    A symposium entitled ''International Meeting on Radiation Processing'' was held in Dubrovnik from 4th to 8th October, 1982. The current status of and the most recent developments in the field of radiation chemistry were presented. In the report presented here the reader is given a critical review of papers presented at the meeting, the following aspects being treated: Radiation measurements and quality control; radiation source technology; environmental application of radiation technology; radiation chemistry as related to nuclear technology; developments in applied polymer chemistry; radiation sterilization; radiation technological aspects in the food industry; low energy electron radiation applications; applied radiation chemistry and physics; bio-compatible materials, radiation plants; engineering economics and process optimization. (orig./RB) [de

  9. Synthesis of EVA/MWNT nanocomposites by radiation induced crosslinking

    International Nuclear Information System (INIS)

    Dubey, K.A.; Bhardwaj, Y.K.; Chaudhari, C.V.; Sabharwal, S.

    2008-01-01

    Full text: EVA is widely used as an insulating material for high voltage cables and in the footwear and toy industries due to its high flexibility and chemical inertness. The nano-composites of EVA with MWNT are of the special interest because incorporation of suitable amount of MWNT in EVA matrix is expected to significantly enhance EVA's thermal and mechanical properties, and open a new domain of applications. The modification of EVA by using high-energy radiation and with particulate filler has been widely practiced; however, there is not much information available on the radiation processing of EVA nanocomposites. To understand the effect of radiation and of MWNT addition on the physico-mechanical characteristics of EVA, different compositions of ethylene vinyl acetate (EVA)/multiple walled carbon nanotube (MWNT) nanocomposites were prepared by mixing in Brabender and subjected to different doses of gamma radiation. The efficiency of radiation vulcanization was analyzed by gel-content, Charlesby-Pinner parameter and crosslinking density measurements. Gamma radiation induced crosslinking was found to increase with MWNT fraction in EVA/MWNT nanocomposites (P o /q o range: 1.15-0.98). These results ruled out the possibility of a significant neutralization of single ionization spurs by MWNT addition. The polymer-filler interaction parameter determined from Kraus plot indicated good interaction between EVA and MWNTs. Storage modulus changed from 7 x 10 7 Pa to 1.8 x 10 8 Pa with incorporation of 5% (wt/wt) MWNT while density increased from 0.78 g/cc to 0.80 g/cc

  10. Radiation processing technology in Malaysia

    International Nuclear Information System (INIS)

    Khairul Zaman Hj Mohd Dahlan

    2004-01-01

    Radiation processing technology is widely used in industry to enhance efficiency and productivity, improve product quality and competitiveness. Efforts have been made by MINT to expand the application of radiation processing technology for modification of indigenous materials such as natural rubber and rubber based products, palm oil and palm oil based products and polysaccharide into new and high value added products. This paper described MINT experiences on developing products through R and D from the laboratory to the pilot plant stage and commercialization. The paper also explained some issues and challenges that MINT encountered in the process of commercialization of its R and D results. (author)

  11. Quality assurance in radiation processing

    International Nuclear Information System (INIS)

    Noriah Mod Ali

    2002-01-01

    The growth of the radiation processing industries in Malaysia has presented the SSDL-MINT a new set of parameter for the Quality Assurance (QA) programs. The large massive doses of radiation required for commercial application of sterilization, cross-linking etc needs measurement method outside the scope of familiar radiation detection instruments. This requires establishment of proper calibration procedure and selection of appropriate transfer system/technique to assure adequate traceability to an international radiation standard. The benefit of accurate in-plant dosimetry for the operator, approving authority and purchaser are balanced against the extra dosimetric efforts required for good QA is presented. (Author)

  12. Development, validation and routine control of a radiation process

    International Nuclear Information System (INIS)

    Kishor Mehta

    2010-01-01

    Today, radiation is used in industrial processing for variety of applications; from low doses for blood irradiation to very high doses for materials modification and even higher for gemstone colour enhancement. At present, radiation is mainly provided by either radionuclides or machine sources; cobalt-60 is the most predominant radionuclide in use. Currently, there are several hundred irradiation facilities worldwide. Similar to other industries, quality management systems can assist radiation processing facilities in enhancing customer satisfaction and maintaining and improving product quality. To help fulfill quality management requirements, several national and international organizations have developed various standards related to radiation processing. They all have requirements and guidelines for development, validation and routine control of the radiation process. For radiation processing, these three phases involve the following activities. Development phase includes selecting the type of radiation source, irradiation facility and the dose required for the process. Validation phase includes conducting activities that give assurance that the process will be successful. Routine control then involves activities that provide evidence that the process has been successfully realized. These standards require documentary evidence that process validation and process control have been followed. Dosimetry information gathered during these processes provides this evidence. (authors)

  13. Recycling of scrap tyres

    International Nuclear Information System (INIS)

    Jana, G.K.; Das, C.K.

    2005-01-01

    De-vulcanization of rubber waste posses a challenging economical, environmental and social problem. In the present study, we propose a new de vulcanization process to reuse the rubber waste called mechan-chemical process (MCP), where the waste were de-vulcanized through the application of mechanical shearing, heat (110 degree C) and de-vulcanizing agent (Di-benzyl disulfide). A new look into the de-vulcanization mechanism and the influence of de-vulcanizing agent on mechanical properties of re-vulcanized rubber was presented. One of the most interesting observations is that the retention of tensile strength of re-vulcanized rubber with respect to original tyre is 35.1% and 75.6%, when de-vulcanized in absence and in presence of disulfide respectively. The formation of extra cross-link bond in re-vulcanized rubber containing disulfide was confirmed from cross-link density data and TGA result. DMA analysis revealed that the storage modulus increased for re vulcanized rubber containing disulfide. The SEM was considered in order to study the failure mechanism and homogeneity as affected by the de vulcanization process

  14. Modification of the properties of NBR/EPDM blends vulcanized by gamma irradiation

    International Nuclear Information System (INIS)

    Abou Zeid, M.M.; Shaltout, N.A.; Mohamed, M.A.; El Miligy, A.A.

    2001-01-01

    Blends of nitrile-butadiene rubber, NBR with ethylene propylene diene monomer EPDM rubber with varying contents have been prepared. Unloaded or loaded blends with 40 phr of HAF carbon black have been vulcanized by using gamma irradiation. Mechanical properties, namely tensile strength, tensile modulus and elongation at break have been followed up as a function of irradiation dose as well as blend component compositions. Moreover, the susceptibility of prepared composites towards organic solvents and car oils has been followed up in terms of swelling number and soluble fraction measurements. The organic solvents used are toluene and dimethyl-formamide and oil are car lubricating and brake oils. The results indicated improvements in mechanical properties of blend composites with irradiation dose and increased content NBR in the blend. Also, susceptibility to fluids decreased appreciably with irradiation dose but with different extents for different fluids

  15. Redox processes in radiation biology and cancer

    International Nuclear Information System (INIS)

    Greenstock, C.L.

    1981-01-01

    Free-radical intermediates, particularly the activated oxygen species OH, O - 2 , and 1 O 2 , are implicated in many types of radiation damage to biological systems. In addition, these same species may be formed, either directly or indirectly through biochemical redox reactions, in both essential and aberrant metabolic processes. Cell survival and adaptation to an environment containing ionizing radiation and other physical and chemical carcinogens ultimately depend upon the cell's ability to maintain optimal function in response to free-radical damage at the chemical level. Many of these feedback control mechanisms are redox controlled. Radiation chemical techniques using selective radical scavengers, such as product analysis and pulse radiolysis, enable us to generate, observe, and characterize individually the nature and reactivity of potentially damaging free radicals. From an analysis of the chemical kinetics of free-radical involvement in biological damage, redox mechanisms are proposed to describe the early processes of radiation damage, redox mechanisms are proposed to describe the early processes of radiation damage, its protection and sensitization, and the role of free radicals in radiation and chemical carcinogenesis

  16. Recycling and processing of several typical crosslinked polymer scraps with enhanced mechanical properties based on solid-state mechanochemical milling

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Canhui; Zhang, Xinxing; Zhang, Wei [State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu 610065 (China)

    2015-05-22

    The partially devulcanization or de-crosslinking of ground tire rubber (GTR), post-vulcanized fluororubber scraps and crosslinked polyethylene from cable scraps through high-shear mechanochemical milling (HSMM) was conducted by a modified solid-state mechanochemical reactor. The results indicated that the HSMM treated crosslinked polymer scraps can be reprocessed as virgin rubbers or thermoplastics to produce materials with high performance. The foamed composites of low density polyethylene/GTR and the blend of post-vulcanized flurorubber (FKM) with polyacrylate rubber (ACM) with better processability and mechanical properties were obtained. The morphology observation showed that the dispersion and compatibility between de-crosslinked polymer scraps and matrix were enhanced. The results demonstrated that HSMM is a feasible alternative technology for recycling post-vulcanized or crosslinked polymer scraps.

  17. Recycling and processing of several typical crosslinked polymer scraps with enhanced mechanical properties based on solid-state mechanochemical milling

    Science.gov (United States)

    Lu, Canhui; Zhang, Xinxing; Zhang, Wei

    2015-05-01

    The partially devulcanization or de-crosslinking of ground tire rubber (GTR), post-vulcanized fluororubber scraps and crosslinked polyethylene from cable scraps through high-shear mechanochemical milling (HSMM) was conducted by a modified solid-state mechanochemical reactor. The results indicated that the HSMM treated crosslinked polymer scraps can be reprocessed as virgin rubbers or thermoplastics to produce materials with high performance. The foamed composites of low density polyethylene/GTR and the blend of post-vulcanized flurorubber (FKM) with polyacrylate rubber (ACM) with better processability and mechanical properties were obtained. The morphology observation showed that the dispersion and compatibility between de-crosslinked polymer scraps and matrix were enhanced. The results demonstrated that HSMM is a feasible alternative technology for recycling post-vulcanized or crosslinked polymer scraps.

  18. Recycling and processing of several typical crosslinked polymer scraps with enhanced mechanical properties based on solid-state mechanochemical milling

    International Nuclear Information System (INIS)

    Lu, Canhui; Zhang, Xinxing; Zhang, Wei

    2015-01-01

    The partially devulcanization or de-crosslinking of ground tire rubber (GTR), post-vulcanized fluororubber scraps and crosslinked polyethylene from cable scraps through high-shear mechanochemical milling (HSMM) was conducted by a modified solid-state mechanochemical reactor. The results indicated that the HSMM treated crosslinked polymer scraps can be reprocessed as virgin rubbers or thermoplastics to produce materials with high performance. The foamed composites of low density polyethylene/GTR and the blend of post-vulcanized flurorubber (FKM) with polyacrylate rubber (ACM) with better processability and mechanical properties were obtained. The morphology observation showed that the dispersion and compatibility between de-crosslinked polymer scraps and matrix were enhanced. The results demonstrated that HSMM is a feasible alternative technology for recycling post-vulcanized or crosslinked polymer scraps

  19. Treatment of Municipal and Industrial Waste by Radiation Processing

    International Nuclear Information System (INIS)

    Abdelaziz, M.E.

    1999-01-01

    In recent years the effort in science and technology is shifting from conventional technologies preventing the pollution of air, water and soil, towards processing by gamma or by electron beam (EB) irradiation in order to prevent pollution, rather than curing the problems caused by production processes, which are not optimized with regard to pollution control. Radiation processing may help to improve the environmental situation in two aspects : It provides alternatives to conventional technologies for the cleaning of air, flue gases and water,...etc, and it also helps to realize clean processes for preventing pollution in the first place. This paper will outline the basic principles of radiation processing for waste streams of environmental relevance, will summarize the state-of -the-art in environmental applications of radiation processing to show both the advantages and the limitations of the radiation processing of waste streams, and to highlight the environmental and economic benefits of clean processes made possible by radiation processing applied to municipal and industrial waste. Reference is made to gamma and EB radiation sources, and description of new technologies is presented

  20. Radiation processing of minimally processed fruits and vegetables to ensure microbiological safety

    International Nuclear Information System (INIS)

    Bandekar, J.R.; Saroj, S.D.; Shashidhar, R.; Dhokane, V.S.; Hajare, S.N.; Nagar, V.; Sharma, A.

    2009-01-01

    Minimally processed fruits and vegetables are in demand as they offer ready rich source of nutrients and convenience to consumers. However, these products are often unsafe due to contamination with harmful pathogens. Therefore, a study was carried out to analyze microbiological quality of minimally processed fruits, vegetables and sprouts and to optimize radiation dose necessary to ensure safety of these commodities. Microbiological quality of these products was found to be poor. Decimal reduction dose (D 10 ) for Salmonella Typhimurium and Listeria monocytogenes in these minimally processed foods (MPF) were in the range of 164 to 588 Gy. Radiation processing with 2 kGy dose of gamma radiation resulted in 5 log reduction of S. Typhimurium and 4 log reduction of L. monocytogenes. The treatment did not significantly affect nutritional, organoleptic and textural properties. These results suggest that radiation processing can ensure safety of these products. (author)

  1. Surface photo reaction processes using synchrotron radiation; Hoshako reiki ni yoru hyomenko hanno process

    Energy Technology Data Exchange (ETDEWEB)

    Imaizumi, Y. [Tohoku University, Sendai (Japan). Institute for Materials Research; Yoshigoe, A. [Toyohashi University of Technology, Aichi (Japan); Urisu, T. [Toyohashi University of Technology, Aichi (Japan). Institute for Molecular Science

    1997-08-20

    This paper introduces the surface photo reaction processes using synchrotron radiation, and its application. A synchrotron radiation process using soft X-rays contained in electron synchrotron radiated light as an excited light source has a possibility of high-resolution processing because of its short wave length. The radiated light can excite efficiently the electronic state of a substance, and can induce a variety of photochemical reactions. In addition, it can excite inner shell electrons efficiently. In the aspect of its application, it has been found that, if radiated light is irradiated on surfaces of solids under fluorine-based reaction gas or Cl2, the surfaces can be etched. This technology is utilized practically. With regard to radiated light excited CVD process, it may be said that anything that can be deposited by the ordinary plasma CVD process can be deposited. Its application to epitaxial crystal growth may be said a nano processing application in thickness direction, such as forming an ultra-lattice structure, the application being subjected to expectation. In micromachine fabricating technologies, a possibility is searched on application of a photo reaction process of the radiated light. 5 refs., 6 figs.

  2. Current status of radiation processing

    International Nuclear Information System (INIS)

    Silverman, J.

    1979-01-01

    A summary is presented of recent developments and problems in the field of radiation processing. Examples are given of a wide range of industrial products and processes. Irradiation plants are discussed. Cross-linking and sterilization are still the principal areas of success. Some setbacks are mentioned, including the appearance of regulatory codes forbidding the use of high energy electrons in the irradiation of food packing materials. Promising applications, such as food sterilization, treatment of sewage and other wastes, chemical synthesis and the curing of paints. The need for more fundamental work on radiation chemistry is stressed. (U.K.)

  3. New trends in radiation processing of polymers

    International Nuclear Information System (INIS)

    Chmielewski, Andrzej G.

    2005-01-01

    Nowadays, the modification of polymers covers radiation cross-linking, radiation induced polymerization (graft polymerization and curing) and the degradation of polymers. The success of radiation technology for the processing of synthetic polymers can be attributed to two reasons, namely the easiness of processing in various shapes and sizes and, secondly, most of these polymers undergo cross-linking reaction upon exposure to radiation. years, natural polymers are being looked at again with renewed interest because of their unique characteristics like inherent biocompatibility, biodegradability and easy availability. However the recent progress in the field regards development of new processing methods and technical solutions. No other break trough technologies or products based on synthetic polymers are reported recently. The future progress, both from scientific and practical points of view, concerns nanotechnology and natural polymer processing. Overview of the subject, including the works performed in the Institute of the author is presented in the paper. (author)

  4. Radiation processing of plastics for decorative purposes

    International Nuclear Information System (INIS)

    Knizhnik, R.I.; Onisko, A.D.

    1982-01-01

    Methods are reviewed for the radiation processing of polymeric films, sheets, plates and panels to form patterns, drawings, images and decorative finishing which have been recently developed in various countries. Methods of beam and radiation processing of transparent plastics are described for making a decorative article with a pattern inside the volume; advantages and shortcomings of the methods are shown. The method of radiation processing of transparent dielectric plastics by electron beam of a Microtron is considered in detail. It provides an economical method of fabrication of large-size highly artistic decorative articles with an original pattern inside the volume. Radiation processing operations are presented which are aimed at creation and visualization of regions of extended thermalized electron space charges stored by irradiation of dielectric. Examples are presented of large-size highly artistic decorative articles of polymethylmethacrylate which were used in interior of buildings and demonstrated at home and international exhibitions. (author)

  5. Applications of nuclear technology in industry, environment and medicine

    International Nuclear Information System (INIS)

    Vera Ruiz, H.

    1998-01-01

    This article contains information on different applications of nuclear technology, such as: sterilization of single use medical products, radiation serialization of pharmaceutical products,radiation treatment of disposable products, in Europe, radiation treatment of micro-titer plates, several crosslinking processes, radiation vulcanization of natural rubber latex, irradiation of polymers to obtain dressings for burns, ulcers bedsores and skin grafts, production of ground water with accelerated electrons in combination with accelerated electrons in combination with ozone, radiation treatment of hospital wastes. (S. Grainger)

  6. A test trial irradiation of natural rubber latex on large scale for the production of examination gloves in a production scale

    International Nuclear Information System (INIS)

    Devendra, R.; Kulatunge, S.; Chandralal, H.N.K.K.; Kalyani, N.M.V.; Seneviratne, J.; Wellage, S.

    1996-01-01

    Radiation Vulcanization of natural rubber latex has been developed extensively through various research and development programme. During these investigations many data was collected and from these data it was proved that radiation vulcanized natural rubber latex (RVNRL) can be used as a new material for industry (RVNRL symposium 1989; Makuuchi IAEA report). This material has been extensively tested in making of dipped goods and extruded products. However these investigations were confined only to laboratory experiments and these experiments mainly reflected material properties of RVNRL and only a little was observed about its behavior in actual production scale operation. The present exercise was carried out mainly to study the behavior of the material in production scale by irradiating latex on a large scale and producing gloves in a production scale plant. It was found that RVNRL can be used in conventional glove plants without making major alteration to the plant. Quality of the gloves that were produced using RVNRL is acceptable. It was also found that the small deviation of vulcanization dose will affect the crosslinking density of films. This will drastically reduce the tensile strength of the film. Crosslinking density or pre-vulcanized relax modulus (PRM) at 100% is a reliable property to control the pre vulcanization of latex by radiation

  7. Process validation for radiation processing

    International Nuclear Information System (INIS)

    Miller, A.

    1999-01-01

    Process validation concerns the establishment of the irradiation conditions that will lead to the desired changes of the irradiated product. Process validation therefore establishes the link between absorbed dose and the characteristics of the product, such as degree of crosslinking in a polyethylene tube, prolongation of shelf life of a food product, or degree of sterility of the medical device. Detailed international standards are written for the documentation of radiation sterilization, such as EN 552 and ISO 11137, and the steps of process validation that are described in these standards are discussed in this paper. They include material testing for the documentation of the correct functioning of the product, microbiological testing for selection of the minimum required dose and dose mapping for documentation of attainment of the required dose in all parts of the product. The process validation must be maintained by reviews and repeated measurements as necessary. This paper presents recommendations and guidance for the execution of these components of process validation. (author)

  8. The new development of radiation processing in China

    International Nuclear Information System (INIS)

    Chen Dianhua

    1998-12-01

    China Isotope and Radiation Association (CIRA) investigated the status of radiation processing in China's mainland. There are 45 accelerators each with beam power over 5 kW, the total beam power is 2005 kW. There are 48 γ facilities each with designed capacity over 1.11 x 10 4 TBq (0.3 million curies) and other 75 units with designed capacity less than 1.11 x 10 4 TBq. The total loaded capacity is 4.63 x 10 5 TBq, more than one third of the designed capacity. radiation processing is mainly used in producing chemical-industrial products (as heat-shrinkable products and radiation cross-linked wire and cable) in China. Some enterprises with annual output value over a hundred million RMB have emerged. Radiation processing is also used in preservation and disinfection of food. In 1977, six kinds of hygienic standards for irradiated food were authorized. Radiation sterilization of disposable medical products, radiation desulphurization and denitration are also being developed in China

  9. Growth of Radiation Processing Plant, Vashi - an overview

    International Nuclear Information System (INIS)

    Singh, Ranjeet

    2014-01-01

    Radiation Processing Plant, Vashi (RPP) is the first commercial scale Gamma Irradiator for food processing in India. The facility was commissioned on 1 st January 2000 with the mandate of showcasing commercial viability of food processing using gamma radiation. Some of the food products that are processed at RPP, Vashi include dehydrated onion powder, coriander, turmeric, black pepper, cumin, pet food and dried seafood items. RPP, Vashi is the largest radiation processor of food products in the country. More than 95% of the quantity processed is exported to various countries generating millions of foreign exchange annually

  10. Atomic spectroscopy and radiative processes

    CERN Document Server

    Landi Degl'Innocenti, Egidio

    2014-01-01

    This book describes the basic physical principles of atomic spectroscopy and the absorption and emission of radiation in astrophysical and laboratory plasmas. It summarizes the basics of electromagnetism and thermodynamics and then describes in detail the theory of atomic spectra for complex atoms, with emphasis on astrophysical applications. Both equilibrium and non-equilibrium phenomena in plasmas are considered. The interaction between radiation and matter is described, together with various types of radiation (e.g., cyclotron, synchrotron, bremsstrahlung, Compton). The basic theory of polarization is explained, as is the theory of radiative transfer for astrophysical applications. Atomic Spectroscopy and Radiative Processes bridges the gap between basic books on atomic spectroscopy and the very specialized publications for the advanced researcher: it will provide under- and postgraduates with a clear in-depth description of theoretical aspects, supported by practical examples of applications.

  11. Concepts of radiation processes selection for industrial realization. Chapter 6

    International Nuclear Information System (INIS)

    1997-01-01

    For selection of radiation processes in industry the processes usually are analyzing by technological and social effects, power-insensitivity, common efficiency. Technological effect is generally conditioned with uniqueness of radiation technologies which allow to obtain new material or certain one but with new properties. Social effect first of all concerns with influence of radiation technologies on consumer's psychology. Implementation of equipment for radiation technological process for both the new material production and natural materials radiation treatment is related with decision of three tasks: 1) Choice of radiation source; 2). Creation of special equipment for radiation and untraditional stages of the process; 3) Selection of radiation and other conditions ensuring of achievement of optimal technological and economical indexes

  12. Applications of radiation processing: SRI experiences

    International Nuclear Information System (INIS)

    Rajput, Sanjay

    2014-01-01

    Shriram Applied Radiation Centre (SARC) is a part of Shriram Institute for Industrial Research (SRI), and was established in 1986, in collaboration with Bhabha Atomic Research Centre (BARC), Board of Radiation and Isotope Technology (BRIT), Department of Atomic Energy (DAE), Atomic Energy Regulatory Board (AERB). SARC was established with a objective to popularize the radiation processing technology for various applications. SARC is a fully automatic, computerized plant setup as per the design and norms of BRIT/AERB for round the clock fail safe operations. The capacity of SARC Irradiator is 800 kCi of Cobalt -60 source which can process up to 10,000 cubic meters of material (0.1g/cc) at 25 kGy level

  13. Avaliação do bis(4-metilfenilditiocarbimatozincato(II de tetrabutilamônio como acelerador no processo de vulcanização do elastômero polibutadieno Evaluation of [tetrabutyl ammonium bis(4-methylphenyldithiocarbimatezincate-2] as accelerator in vulcanization process of polybutadiene elastomer

    Directory of Open Access Journals (Sweden)

    Leonardo F. V. dos Santos

    2011-01-01

    Full Text Available O ZNIBU, acelerador de caráter lento foi avaliado neste trabalho em composições de polibutadieno. Este acelerador foi sintetizado com o objetivo de substituir, ou reduzir, o uso de alguns aceleradores comerciais muito utilizados em composições elastoméricas mas que, por serem formadores de nitrosaminas, podem ser prejudiciais à saúde. A fim de corrigir o caráter de acelerador lento do ZNIBU, este composto foi utilizado em conjunto com o acelerador comercial CBS (N-ciclohexil-2-benzotiazol-2-sulfenamida. Foi observado que pequenas quantidades dos dois aceleradores não são efetivas na aceleração da vulcanização nas composições do tipo goma pura. No entanto a presença de negro de fumo exerce um efeito positivo sobre a velocidade. As propriedades mecânicas estudadas mostram que o ZNIBU aumenta a resistência à tração da goma pura (35%, em comparação com a composição similar vulcanizada com CBS e, na presença do negro de fumo, este aumento é ainda mais expressivo (175%. Quanto à resistência ao rasgamento, a vulcanização com o ZNIBU forneceu o mais baixo valor da propriedade para a goma pura, enquanto que a composição com negro de fumo apresentou o mais alto valor.ZNIBU, a slow accelerator, was evaluated in polybutadiene compositions. This accelerator was synthesized intending to replace or reduce the use of some very used commercial accelerators in rubber compositions which, due to their nitrosamine-forming potential, can be harmful to health. In order to correct for the slow accelerating character ZNIBU was used in combination with the commercial accelerator CBS (N-cyclohexyl-2-benzothiazole-2-sulfenamide. It was observed that small amounts of the accelerators are not effective in the vulcanization accelerating process of gum type compositions. Nevertheless, the presence of carbon black exerts a positive effect on the reaction rate. The investigated mechanical properties show that ZNIBU improves stress strength of

  14. Radiation processing of natural polymers: The IAEA contribution

    Science.gov (United States)

    Haji-Saeid, Mohammad; Safrany, Agnes; Sampa, Maria Helena de O.; Ramamoorthy, Natesan

    2010-03-01

    Radiation processing offers a clean and additive-free method for preparation of value-added novel materials based on renewable, non-toxic, and biodegradable natural polymers. Crosslinked natural polymers can be used as hydrogel wound dressings, face cleaning cosmetic masks, adsorbents of toxins, and non-bedsore mats; while low molecular weight products show antibiotic, antioxidant, and plant-growth promoting properties. Recognizing the potential benefits that radiation technology can offer for processing of natural polymers into useful products, the IAEA implemented a coordinated research project (CRP) on "Development of Radiation-processed products of Natural Polymers for application in Agriculture, Healthcare, Industry and Environment". This CRP was launched at the end of 2007 with participation of 16 MS to help connecting radiation technology and end-users to derive enhanced benefits from these new value-added products of radiation-processed natural materials. In this paper the results of activities in participating MS related to this work will be presented.

  15. Radiation processing of natural polymers: The IAEA contribution

    International Nuclear Information System (INIS)

    Haji-Saeid, Mohammad; Safrany, Agnes; Sampa, Maria Helena de O.; Ramamoorthy, Natesan

    2010-01-01

    Radiation processing offers a clean and additive-free method for preparation of value-added novel materials based on renewable, non-toxic, and biodegradable natural polymers. Crosslinked natural polymers can be used as hydrogel wound dressings, face cleaning cosmetic masks, adsorbents of toxins, and non-bedsore mats; while low molecular weight products show antibiotic, antioxidant, and plant-growth promoting properties. Recognizing the potential benefits that radiation technology can offer for processing of natural polymers into useful products, the IAEA implemented a coordinated research project (CRP) on 'Development of Radiation-processed products of Natural Polymers for application in Agriculture, Healthcare, Industry and Environment'. This CRP was launched at the end of 2007 with participation of 16 MS to help connecting radiation technology and end-users to derive enhanced benefits from these new value-added products of radiation-processed natural materials. In this paper the results of activities in participating MS related to this work will be presented.

  16. Apparatus and method for radiation processing of materials

    International Nuclear Information System (INIS)

    Neuberg, W.B.; Luniewski, R.

    1983-01-01

    A method and apparatus for radiation degradation processing of polytetrafluoroethylene makes use of a simultaneous irradiation, agitation and cooling. The apparatus is designed to make efficent use of radiation in the processing. (author)

  17. Some novel concepts in radiation processing technology applications

    International Nuclear Information System (INIS)

    Varshney, Lalit

    2014-01-01

    Search for better materials and processes has been a part of the evolution of mankind and it still continues to be so as it is being realized that earth's resources are not everlasting and effect of rapid growth on environment may adversely affect the future development. Sustainable development is the only choice for today for long term survival. Better quality and high functional materials, made by superior technologies are being demanded by the society. Radiation processing technology has significantly contributed to meet the expectation of the people in providing superior products and processes while preserving the environment. Processes are being developed where resources are fully utilized with maximum advantages and little disturbance to the environment. More than 1500 electron beam accelerators and about 500 Gamma Irradiators are presently in use and many are being deployed for radiation processing of medical supplies, pharmaceuticals and herbal materials, treat effluents and preserve food and agricultural products and several industrial products. DAE has an ambitious plan to deploy radiation technology for societal benefits in India. In the presentations some interesting applications of Radiation Processing Technology will be discussed which includes (1) Radiation Processing of Cashew Apple fruit for bio-ethanol production (2) High Energy Battery separators (3) Plant Growth Promoters and (4) Tunable biodegradability. The discussion would reveal how a waste product like cashew apple can be converted to useful materials and advanced materials like HEB separators and Tunable Biodegradable films can be made using radiation technology. Use of radiation de-polymerized polysaccharides in some experiments have shown unexpected increase in agriculture output giving new concepts to increase the productivity. (author)

  18. Mineralogical and structural transformations related to alterations in hydrothermal and climatological conditions of basic vulcanic rocks from northern Parana (Ribeirao Preto region, SP, Brazil)

    International Nuclear Information System (INIS)

    Goncalves, N.M.M.

    1987-01-01

    Detailed studies of the basic vulcanic rocks of northern Parana basin (Region of Ribeirao Preto, SP) reveled that these rocks were affected by pre-meteoric activity (hydrothermal alteration) before being exposed to the supergene system of alteration linked to the lithosphere/atmosphere interface. Mineralogical and structural transformation are studied. The appearance of sequential crystalline-chemical paragenesis in zones suggest that the hydrothermal activity occurred during two successives processes of alteration: the expulsion of the water from the rock during the later stages of magma cooling and the continous process of dissolution of the rock wall and the ionic diffusion involving the rock sistem of structural voids. The hydro-thermal action was followed by weathering action developing a thin 'front' of superficial alteration. This alteration system, can lead to the formation of three major levels of alteration horizons and superficial accumulations: alterites, glebular and suil surface materials. (C.D.G.) [pt

  19. GURU v2.0: An interactive Graphical User interface to fit rheometer curves in Han's model for rubber vulcanization

    Science.gov (United States)

    Milani, G.; Milani, F.

    A GUI software (GURU) for experimental data fitting of rheometer curves in Natural Rubber (NR) vulcanized with sulphur at different curing temperatures is presented. Experimental data are automatically loaded in GURU from an Excel spreadsheet coming from the output of the experimental machine (moving die rheometer). To fit the experimental data, the general reaction scheme proposed by Han and co-workers for NR vulcanized with sulphur is considered. From the simplified kinetic scheme adopted, a closed form solution can be found for the crosslink density, with the only limitation that the induction period is excluded from computations. Three kinetic constants must be determined in such a way to minimize the absolute error between normalized experimental data and numerical prediction. Usually, this result is achieved by means of standard least-squares data fitting. On the contrary, GURU works interactively by means of a Graphical User Interface (GUI) to minimize the error and allows an interactive calibration of the kinetic constants by means of sliders. A simple mouse click on the sliders allows the assignment of a value for each kinetic constant and a visual comparison between numerical and experimental curves. Users will thus find optimal values of the constants by means of a classic trial and error strategy. An experimental case of technical relevance is shown as benchmark.

  20. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Kumar, A.; Reddy, A.R.

    1994-01-01

    The last few years have seen a significant increase in the use of ionising radiation in industrial processes and also international trade in irradiated products. With this, the demand for internationally accepted dosimetric techniques, accredited to international standards has also increased which is further stimulated by the emergence of ISO-9000 series of standards in industries. The present paper describes some of the important dosimetric techniques used in radiation processing, the role of IAEA in evolving internationally accepted standards and work carried out at the Defence Laboratories, Jodhpur in the development of a cheap, broad dose range and simple dosimeter for routine dosimetry. For this polyhydroxy alcohols viz., mannitol, sorbitol and inositol were studied using the spectrophotometric read out method. Out of the alcohols studied mannitol was found to be most promising covering a dose range of 0.01 kGy - 100 kGy. (author). 26 refs., 3 figs., 1 tab

  1. Flavor profile of radiation processed food commodities

    International Nuclear Information System (INIS)

    Chatterjee, S.; Variyar, Prasad S.; Sharma, Arun

    2006-01-01

    Full text: Flavor is one of the major quality attributes that play an important role in driving consumer choices and preferences for food. Among the several attributes that decide the flavor quality of any food, aroma and taste are the most important. While volatile constituents contribute to aroma, taste is a perception stimulated by non-volatile principles of food. Radiation processing of food has in recent years assumed increasing importance as a method for hygenization. At the doses employed for food irradiation no significant qualitative changes in the aroma constituents have been reported in most cases. An increase in perceived aroma has however been observed in several radiation processed foods. Besides volatile aroma compounds non-volatile aroma precursors are ubiquitous in plant kingdom. These compounds have been reported to exist largely as bound glycosidic conjugates and are known to undergo breakdown during processing and storage. This results in release of free aroma, thereby, modifying the flavor quality of the product. No report, however, exists on the effect of radiation processing on these bound aroma precursors. Four major class of food namely spices, oil seeds, fruits and beverages were therefore taken up for a detailed study. With respect to aroma, an enhanced breakdown of aroma precursors namely isoeugenol and 4-vinyl guaiacol glycosides and release of free aglycones was demonstrated to result in an increased aroma quality of radiation processed monsooned coffee. Breakdown of phenyl ethanol glucoside resulted in a fruitier note to pomegranate while enhanced spicy note of irradiated nutmeg arise as a result of radiolytic break down p-cymene-7-ol rutinoside precursor and release of free p-cymene-7-ol. An increased color quality of irradiated saffron was a result of the formation of free carotene aglycones namely crocetin from its glycosidic precursors while changes in perceived taste quality of radiation processed soybean could be attributed to

  2. Some features of radiation processing in the plastics industry

    International Nuclear Information System (INIS)

    Dobo, J.

    1985-01-01

    In the last few years, the production of free radicals by radiation became competitive with chemical initiators. Nevertheless radiation processing got only a firm footing, where distinct advantages could be demonstrated as compared with conventional processes, either in the technology or the product quality. This paper is intended to direct attention to some of the special features of radiation processing. (author)

  3. Some features of radiation processing in the plastics industry

    Science.gov (United States)

    D´, J.

    In the last few years, the production of free radicals by radiation became competitive with chemical initiators. Nevertheless, radiation processing got only a firm footing, where distinct advantages could be demonstrated as compared with conventional processes, either in the technology or the product quality. This paper is intended to direct attention to some of the special features of radiation processing.

  4. Dosimetry as an integral part of radiation processing

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1999-01-01

    Different connections between high-dose dosimetry and radiation processing are discussed. Radiation processing cannot be performed without proper dosimetry. Accurate high dose and high dose rate dosimetry exhibits several aspects: first of all it is the preservation of the quality of the product, then fulfillment of legal aspects and last but not the least the safety of processing. Further, seldom discussed topics are as follow: dosimetric problems occurring with double-side EB irradiations, discussed in connection with the deposition of electric charge during electron beam irradiation. Although dosimetry for basic research and for medical purposes are treated here only shortly, some conclusions reached from these fields are considered in dosimetry for radiation processing. High-dose dosimetry of radiation has become a separate field, with many papers published every year, but applied dosimetric projects are usually initiated by a necessity of particular application. (author)

  5. Use of ionising radiation for food processing applications

    International Nuclear Information System (INIS)

    Ninjoor, V.

    1989-01-01

    Food irradiation is a recently developed technique used to sterilize and preserve food. Food products are exposed to ionising radiations such as X-rays, gamma rays or high energy electrons which destroy food borne pathogens and parasites and inhibit sprouting. Shelf life of food is extended. The following aspects of radiation processing of food are discussed in the monograph: radiation sources, choice of dose for specific results, safety and nutritional quality of radiation processed food, international status of acceptance of food irradiation, and cost. (M.G.B.). 6 tabs

  6. Application of Java technology in radiation image processing

    International Nuclear Information System (INIS)

    Cheng Weifeng; Li Zheng; Chen Zhiqiang; Zhang Li; Gao Wenhuan

    2002-01-01

    The acquisition and processing of radiation image plays an important role in modern application of civil nuclear technology. The author analyzes the rationale of Java image processing technology which includes Java AWT, Java 2D and JAI. In order to demonstrate applicability of Java technology in field of image processing, examples of application of JAI technology in processing of radiation images of large container have been given

  7. Packaging materials for use in radiation processing of foods

    International Nuclear Information System (INIS)

    Dragusin, M.; Rotaru, P.R.

    1999-01-01

    In radiation processing of food, the product often has to be prepackaged to prevent microbial recontamination during and after irradiation. The packaging material is exposed to radiation during radiation processing and radiation stability is a key consideration in the selection of packaging materials. The effects of ionizing radiation on many food packaging materials at the dose levels recommended for food precessing can be minimized by selecting appropriate radiation resistant materials. It is important to select materials in which chemicals formed as a result of the radiation treatment do not migrate and interact with the food, affecting its organoleptic and toxicological aspects. It is also important to select materials in which the physical properties are not altered to the extent they cannot resist damage during commercial production, shipment and storage. Radiation treatment of food may be classified broadly into two categories: 1. Processes requiring doses less than 10 kGy; 2. Processes requiring doses from 25 to 40 kGy for production of commercial sterility. In radiation processing of foods, gamma radiation from radioisotopes Co-60 and Cs-137 is most widely used because of its high penetrating power. Electron beam irradiation (E<10 MeV) and X-rays (E<5 MeV) can also be used for certain speciality food and packaging to the food. Because the public acceptance of irradiated foods is a major problem in marketing such products, we have developed in our laboratory an alternative techniques. These techniques are based on applying films on the surfaces of foods. The films are edible, i.e. they are an aqueous solution based on caseine, glycerine, poly-etilene-glycol (PEG), crosslinked by radiation processing. So, our techniques implies no longer the food irradiation but instead its isolation from the environmental biological attacks by means of edible films obtained by irradiation. The protective properties of films, as special humidity, oxygen and fat barriers, are

  8. The working of RVNRL pilot plant of Rubber Board and it's safety devices

    International Nuclear Information System (INIS)

    Britto, I.J.; Thomas, E.V.

    1996-01-01

    A pilot plant for producing radiation vulcanized natural rubber latex (RVNRL) was established at Rubber Board, India in 1992. Irradiation is done by a batch process in the plant. The plant has a versatile safety system for safety of operators and people working in and around the plant

  9. Irradiated latex as an economical raw material for making gloves with a simple technique

    International Nuclear Information System (INIS)

    Utama, Marga

    1983-01-01

    The radiation vulcanization process with stirring method at 3 Mrad irradiation dose has been done. Glove production at ''HOME INDUSTRY'' scale be commercially applied. The physical and mechanical properties, such as modulus, tensile strength, permanent set, and elongation at break, of the gloves can satisfy the standard requirements. (author)

  10. Radiation processing of food

    International Nuclear Information System (INIS)

    Saint-Lebe, L.; Raffi, J.

    1983-06-01

    The ionizing radiations available for food processing are defined, their mode of action and principal effects are described. Toxicological studies (animal tests, radiochemistry) concerning irradiated food are reviewed. The characteristics of the irradiation procedure and the prospects of its industrial development in France are presented [fr

  11. Radiative processes in gauge theories

    International Nuclear Information System (INIS)

    Berends, F.A.; Kleiss, R.; Danckaert, D.; Causmaecker, P. De; Gastmans, R.; Troost, W.; Tai Tsun Wu

    1982-01-01

    It is shown how the introduction of explicit polarization vectors of the radiated gauge particles leads to great simplifications in the calculation of bremsstrahlung processes at high energies. (author)

  12. Radiation processing activities at OGFL

    International Nuclear Information System (INIS)

    Sarkar, Atish

    2014-01-01

    CONCAST group of Industries has set up the first Radiation Processing Plant in Eastern India as 'VIKIRAN' named as Organic Green Foods Ltd., situated at Dankuni (Durgapur Highway Express) 25 km away from central Kolkata on August 21, 2004. Shri Sanjay Sureka, Managing Director of Organic Green Foods Ltd., Kolkata belongs to the famous CONCAST Group of Industries operates the largest plant of West Bengal engaged in manufacturing of Steel Industry. The facility was aimed at improving the quality of healthcare products and devices as well as Laboratory, Spice, Herbal and Ayurvedic Products of large volumes on an industrial scale. The operation of VIKIRAN for the last ten years, has unambiguously proved that both the above objectives have been fully met and now radiation sterilization has emerged as an efficient and effective industrial process. The irradiator is a panoramic wet storage class-IV type. This Facility is designed for 1000 KCi activity of source and is suitable in medium and high dose range application. VIKIRAN offers radiation sterilization service to more than 100 manufacturers

  13. Radiation chemistry - extravaganza or an integral component of radiation processing of food

    International Nuclear Information System (INIS)

    Simic, M.G.; DeGraff, E.

    1983-01-01

    The role of radiation chemistry in radiation processing of foods is discussed in detail. A few examples demonstrating the relevance of the radiation chemistry of model systems to food-irradiation technology are given. The importance of irradiation parameters such as dose, dose rate, temperature, atmosphere, physical state and additives in achieving acceptable and high quality of irradiated foods are emphasized. A few examples of radiation-induced free radical reactions in model compounds relevant to foods are also discussed. (author)

  14. Kinetic and radiation processes in cluster plasmas

    International Nuclear Information System (INIS)

    Smirnov, B.M.

    1996-01-01

    The analysis of processes is made for a cluster plasma which is a xenon arc plasma of a high pressure with an admixture of tungsten cluster ions. Because cluster ions emit radiation, this system is a light source which parameters are determined by various processes such as heat release and transport of charged particles in the plasma, radiative processes involving clusters, processes of cluster evaporation and attachment of atoms to it that leads to an equilibrium between clusters and vapor of their atoms, processes of cluster generation, processes of the ionization equilibrium between cluster ions and plasma electrons, transport of cluster ions in the discharge plasma in all directions. These processes govern by properties of a specific cluster plasma under consideration. (author)

  15. Dosimetry control for radiation processing - basic requirements and standards

    International Nuclear Information System (INIS)

    Ivanova, M.; Tsrunchev, Ts.

    2004-01-01

    A brief review of the basic international codes and standards for dosimetry control for radiation processing (high doses dosimetry), setting up a dosimetry control for radiation processing and metrology control of the dosimetry system is made. The present state of dosimetry control for food processing and the Bulgarian long experience in food irradiation (three irradiation facilities are operational at these moment) are presented. The absence of neither national standard for high doses nor accredited laboratory for calibration and audit of radiation processing dosimetry systems is also discussed

  16. Cinética de vulcanização de composições de borracha natural com incorporação de cinza de casca de arroz Vulcanization kinetics of natural rubber filled with rice husk ash

    Directory of Open Access Journals (Sweden)

    Helson M. da Costa

    2003-06-01

    Full Text Available Cinza da casca de arroz foi incorporada em borracha natural (NR utilizando-se um misturador de cilindros. O sistema de vulcanização convencional (CV foi escolhido e os estudos sobre a cura das composições foram conduzidos em um Curômetro TI-100. As curvas de torque foram obtidas em 150, 160, 170 e 180 °C. A velocidade global e a energia de ativação aparente para o processo de vulcanização foram calculadas para cada composição, assumindo que a vulcanização segue uma cinética de primeira ordem. Para fins de comparação, duas cargas comerciais, sílica precipitada (Zeosil-175 e negro de fumo (N762, foram também usadas. Foi observado que a adição da cinza da casca de arroz às composições de NR, em comparação às outras cargas utilizadas, aumentou a velocidade de reticulação e diminuiu a energia de ativação aparente de modo mais marcante.Rice husk ash was incorporated into natural rubber (NR using a laboratory size two-roll mill. A conventional vulcanization system (CV was chosen and cure studies were carried out on a TI-100 Curometer. The torque curves were obtained at 150, 160, 170, and 180 °C. The overall rate and the apparent activation energy for the vulcanization process were calculated for each compound assuming that vulcanization follows first-order kinetics. For the purpose of comparison, two commercial fillers, precipitated silica (Zeosil-175 and carbon black (N762, were also used. In comparison to the other fillers used, the addition of rice husk ash to NR compounds increased the crosslinking rate and lowered the apparent activation energy in a more marked way.

  17. News from Front (of the Solar System): the problem with Mercury, the Vulcan hypothesis, and General Relativity's first astronomical triumph

    Science.gov (United States)

    Sheehan, William

    2016-01-01

    The discovery of the outer planet Neptune in 1846, based on the calculated position published by Urbain Jean Joseph Le Verrier, has been hailed as the "zenith of Newtonian mechanics." An attempt by Le Verrier to further extend the dominion of Newton's gravitational theory to the innermost known planet of the Solar System, Mercury, seemingly came to grief with the discovery of a small unexplained discrepancy in the precession of the perihelion of Mercury, whose value was later calculated as 43".0 per century. Le Verrier proposed that it could be explained on the basis of Newtonian theory by assuming the existence of an intra-mercurial planet ("Vulcan") or ring of debris. Efforts to confirm this hypothesis, culminating in high drama on the plains of the western United States at the great North American solar eclipse of July 1878, proved futile; by 1908, W. W. Campbell and C.D. Perrine of Lick Observatory, who had carried out exhaustive photographic searches at three eclipses (1901, 1905, and 1908) could declare that Vulcan did not exist. The theoretical problem it was invoked to explain remained until November 1915, when Albert Einstein used the recently discovered generally covariant gravitational equations to put the problem to rest. "Perihelion motions explained quantitatively … you will be astonished," he wrote to his friend Michael Besso.

  18. GURU v2.0: An interactive Graphical User interface to fit rheometer curves in Han’s model for rubber vulcanization

    Directory of Open Access Journals (Sweden)

    G. Milani

    2016-01-01

    Full Text Available A GUI software (GURU for experimental data fitting of rheometer curves in Natural Rubber (NR vulcanized with sulphur at different curing temperatures is presented. Experimental data are automatically loaded in GURU from an Excel spreadsheet coming from the output of the experimental machine (moving die rheometer. To fit the experimental data, the general reaction scheme proposed by Han and co-workers for NR vulcanized with sulphur is considered. From the simplified kinetic scheme adopted, a closed form solution can be found for the crosslink density, with the only limitation that the induction period is excluded from computations. Three kinetic constants must be determined in such a way to minimize the absolute error between normalized experimental data and numerical prediction. Usually, this result is achieved by means of standard least-squares data fitting. On the contrary, GURU works interactively by means of a Graphical User Interface (GUI to minimize the error and allows an interactive calibration of the kinetic constants by means of sliders. A simple mouse click on the sliders allows the assignment of a value for each kinetic constant and a visual comparison between numerical and experimental curves. Users will thus find optimal values of the constants by means of a classic trial and error strategy. An experimental case of technical relevance is shown as benchmark.

  19. n-BA/KOH/t-BHP behaviour in the natural rubber latex vulcanization by gamma rays

    International Nuclear Information System (INIS)

    Souza, A. de.

    1994-01-01

    Natural rubber latex was vulcanized in the absence and in the presence of sensitizer (S), with gamma ray from 60 Co source, panoramic type, at the dose rate range of 1,20-1,33 kGy/h. The components of used S were n-butyl acrylate (n-BA), the KOH as stabilizer and t-butyl hydroperoxide (t-BHP) as co-S. The purpose of this work was to study the efficiency and the behaviour of each component of S in the irradiated latex crosslinking by tensile strength (T b ), volume fraction and permanent set. In the absence of S occur straight crosslinking between macromolecular adjacent radicals. IN the presence of S, the n-BA participates in the crosslinking through acrylic bridges between macromolecules. (author)

  20. Processing of oil products using complex radiation-thermal treatment and radiation oxonolysis

    International Nuclear Information System (INIS)

    Zaikin, Yu.A.; Zaikina, R.F.

    2002-01-01

    Most of industrial radiation facilities afford an opportunity to produce a considerable amount of reactive ozone-containing gaseous mixtures parallel to the basic production that causes no detriment to the output of the main designed product. The synergetic action of the ozone-containing mixtures and ionizing radiation is of a special interest for industrial application since it can be efficiently used in a wide range of technologies, in particular, for stimulation of chemical conversion in hydrocarbons accompanied by intensive oxidizing processes. In this paper the effect of simultaneous radiation-thermal processing and radiation oxonolysis on hydrocarbon chemical conversion, and subsequent alterations in composition and properties of oil products were studied on the example of high-viscous oil (Karazhanbas field, Kazakhstan) subjected to irradiation by 2 MeV electrons combined with radiation ozonization in the bubbling mode. It was stated that application of the bubbling mode for radiation-induced ozonization of high-viscous oil leads to decrease in the yields of engine fuels in average by 8-10 % compared with those obtained in the conditions when radiation-thermal cracking was applied without bubbling. In the latter case mean yields of the wide gas-oil fraction with boiling start temperature of 350 deg. C, that included gasoline, kerosene, and diesel fuel, were about 76-80 %. Decrease in the gasoline yields does not lead to noticeable alterations in hydrocarbon contents of the gasoline fraction (boiling beginning bellow 175 deg. C) compared with gasoline produced be radiation-thermal cracking, in both cases it meets requirements for high quality standards. However, essential difference was observed in properties of heavy residua of oil processing (oil fractions with T boil >350 deg. C), i.e. the fractions that contained high concentrations of asphaltenes and pitches. Application of radiation oxonolysis diminishes concentrations of high-molecular aromatic

  1. Dosimetry standards for radiation processing

    International Nuclear Information System (INIS)

    Farrar, H. IV

    1999-01-01

    For irradiation treatments to be reproducible in the laboratory and then in the commercial environment, and for products to have certified absorbed doses, standardized dosimetry techniques are needed. This need is being satisfied by standards being developed by experts from around the world under the auspices of Subcommittee E10.01 of the American Society for Testing and Materials (ASTM). In the time period since it was formed in 1984, the subcommittee has grown to 150 members from 43 countries, representing a broad cross-section of industry, government and university interests. With cooperation from other international organizations, it has taken the combined part-time effort of all these people more than 13 years to complete 24 dosimetry standards. Four are specifically for food irradiation or agricultural applications, but the majority apply to all forms of gamma, x-ray, Bremsstrahlung and electron beam radiation processing, including dosimetry for sterilization of health care products and the radiation processing of fruits, vegetables, meats, spices, processed foods, plastics, inks, medical wastes and paper. An additional 6 standards are under development. Most of the standards provide exact procedures for using individual dosimetry systems or for characterizing various types of irradiation facilities, but one covers the selection and calibration of dosimetry systems, and another covers the treatment of uncertainties. Together, this set of standards covers essentially all aspects of dosimetry for radiation processing. The first 20 of these standards have been adopted in their present form by the International Organization of Standardization (ISO), and will be published by ISO in 1999. (author)

  2. Effective closed form mathematical approach to determine kinetic constants of NR vulcanized with sulphur and accelerators at different concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Milani, Gabriele, E-mail: milani@stru.polimi.it, E-mail: gabriele.milani@polimi.it [Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Hanel, Thomas; Donetti, Raffaella [Pirelli Tyre, Via Alberto e Piero Pirelli 25, 20126 Milan (Italy); Milani, Federico [CHEMCO Consultant, Via J.F. Kennedy 2, 45030 Occhiobello (Italy)

    2015-03-10

    The basic reaction scheme due to Han and co-workers for NR vulcanized with sulphur is adopted and modified taking into account the single contributions of the different accelerators, focusing in particular on some experimental data ad hoc obtained at Pirelli’s laboratories, where NR was vulcanized at different temperatures (from 150 to 180 °C) and concentrations of sulphur, using TBBS and DPG in the mixture as co-agents. Typically, the chain reactions are initiated by the formation of macro-compounds that are responsible of the formation of the unmatured crosslinked polymer. This first reaction depends on the reciprocal concentrations of all components and their chemical nature. In presence of two accelerators, it was considered that the reactions between each single accelerator and the NR raw material occur in parallel, making the reasonable assumption that there are no mutual reactions between the two accelerators. From the kinetic scheme adopted, a closed form solution was found for the crosslink density, with the only limitation that the induction period is excluded from computations. Even kinetic constants are evaluated in closed form, avoiding a numerically demanding least-squares best fitting on rheometer experimental data. Two series of experiments available, relying into rheometer curves at different temperatures and different concentrations of sulphur and accelerator, are utilized to evaluate the fitting capabilities of the mathematical model. Very good agreement between numerical output and experimental data is experienced in all cases analysed.

  3. Radiation processing and functional properties of soybean (Glycine max)

    International Nuclear Information System (INIS)

    Pednekar, Mrinal; Das, Amit K.; Rajalakshmi, V; Sharma, Arun

    2010-01-01

    Effect of radiation processing (10, 20 and 30 kGy) on soybean for better utilization was studied. Radiation processing reduced the cooking time of soybean and increased the oil absorption capacity of soy flour without affecting its proximate composition. Irradiation improved the functional properties like solubility, emulsification activity and foam stability of soybean protein isolate. The value addition effect of radiation processing has been discussed for the products (soy milk, tofu and tofu fortified patties) prepared from soybean.

  4. Principles of interaction of ionizing radiation with matter and basic radiation chemistry processes

    International Nuclear Information System (INIS)

    Santar, I.; Bednar, J.

    1976-01-01

    The basic principles are given of the interaction of ionizing radiation with matter and the main trends are pointed out in radiation chemistry. A brief characteristics is given of the basic radiation chemical processes in gases and in the condensed phase, namely in water and in organic substances. (B.S.)

  5. Industrialization drive of radiation processing for economic growth in China

    International Nuclear Information System (INIS)

    Lu Yanxiao

    1996-12-01

    The transfer of research and development achievements of radiation processing to routine industrial applications in China is reviewed. While making a brief survey of historical background, the paper indicates the different roles that various domestic organizations played in the industrialization drive of radiation processing. Among them the Government's role is the most important one. In accordance with recent growth of the number of industrial radiation facilities (e.g. cobalt-60 irradiators and electron beam accelerators) and current application of radiation processing in main fields in different parts of the country, it can be said that a new radiation processing industry is shaping up in its developing stage to satisfy the growing requirements for economic booming in China. (16 refs.)

  6. Decease of accelerator size for radiation processing

    International Nuclear Information System (INIS)

    Tanaka, Ryuichi; Sunaga, Hiromi

    2003-01-01

    The decrease of accelerator size is an essential means to improve the market competition power of the radiation processing industry and to expand the wide application. Trials for the decrease or minimization are increasing steadily including development of irradiation equipments for exclusive uses. Compact irradiation systems were outlined for the significance and recent examples of the decrease in radiation processing, the problems in the industrial application, and the future of compact accelerators. (author)

  7. Recent developments in the field of radiation processing

    International Nuclear Information System (INIS)

    Andrzej, G. Chmielewski

    2006-01-01

    Full text: Radiation has been discovered more than one hundred years ago. Since than, properties of radiation to modify physico-chemical properties of materials have found many applications. Radiation technologies applying gamma sources and electron accelerators for material processing are well established processes. There are over 160 gamma industrial irradiators and 1300 electron industrial accelerators in operation worldwide. They are being widely used for sterilization, food irradiation and polymer processing. New developments in the field of radiation sources engineering are compact size gamma irradiators, high power electron accelerators (medium energy range) for environmental applications and other types (high energy range) for materials' processing, with direct e-/X conversion. Future applications of low energy, inexpensive EB processing systems are foreseen. Electron beam lithography for microelectronics is a well-established technique. The already tested e-/X system equipped in an accelerator of 700 kW power opens new horizons for this kind of application. The developments described above need introduction of new computational methods that facilitate prediction of dose distribution, even in containers filled with complex products of varying densities. This technique provides good solutions for homeland security applications which may be complemented by mobile system applications. Technologies to be developed besides environmental applications could be nano materials, structure engineered materials (sorbents, the composites, ordered polymers, etc.) and natural polymers' processing. New products based on radiation processed polysaccharides have already been commercialized in many countries of the East Asia and Pacific Region, especially in those being rich in natural polymers. Very important and promising applications concern environment protection - radiation technology being a clean and environment friendly process, helps to curb pollutants' emission as

  8. UV and EB radiation processing in developing countries

    International Nuclear Information System (INIS)

    Garnett, J.L.

    1991-01-01

    Ultraviolet and electron beams (EB) are to be considered as complementary technologies in the radiation processing field. In many countries, UV processing is used as the pathfinder for EB. In the developing countries the decision to adopt radiation processing techniques to choose between UV and EB will largely be determined by economics, the availability of the chemists and also skilled personnel to service both lines and equipment. (orig./A.B.)

  9. Innovative Applications in Radiation Processing

    International Nuclear Information System (INIS)

    Vroom, D.A.

    2006-01-01

    Prior to acquisition by Tyco International, Raychem Corporation initiated several programs to develop new products, reduce the production cost of existing products and identify new market areas that would utilize the skills available in the company in the area of radiation chemistry and radiation technology. Several areas were considered including radiation initiation of specific chemical reactions in polymers at high temperatures, the use of purpose built irradiation equipment for low cost production of specific high volume products and environmental remediation of ground or waste water. In this regard, the Corporation supported a program to improve how material is processed through an electron accelerator and to develop specific equipment to utilize these improvements. The goal was to make the radiation process a single entity as opposed to an accelerator and a material handling system. This paper discusses some of the developments from this program. In the area of radiation induced chemical reactions in polymers at elevated temperatures, a robust accelerator was developed that would allow the irradiation of polymeric materials in the melt as they exited forming equipment such as plastics extruders. Here the goal was to have a low energy, self shielded accelerator in the 300 KeV to 500 KeV range in which extruded polymeric material could be immediately processed in a single pass at melt temperature before it was cooled and allowed to encounter any surfaces. Two machines that met these criteria were constructed and will be discussed. Several of the innovations coming from the high processing temperature, single pass accelerator project were incorporated into the development of purpose built machines to process specific existing products such as wire and heat shrink tubing. Here the goal was to have machines with the minimum acceptable electron energy and compact shielding to reduce cost and foot print. Beam scanning technology developed will be discussed. A major

  10. Influence of radiation processing of grapes on wine quality

    International Nuclear Information System (INIS)

    Gupta, Sumit; Padole, Rupali; Variyar, Prasad S.; Sharma, Arun

    2015-01-01

    Grapes (Var. Shiraz and Cabernet) were subjected to radiation processing (up to 2 kGy) and wines were prepared and matured (4 months, 15 °C). The wines were analyzed for chromatic characteristics, total anthocyanin (TA), phenolic (TP) and total antioxidant (TAC) content. Aroma of wines was analyzed by GC/MS and sensory analysis was carried out using descriptive analysis. TA, TP and TAC were 77, 31 and 37 percent higher for irradiated (1500 Gy) Cabernet wines, while irradiated Shiraz wines demonstrated 47, 18 and 19 percent higher TA, TP and TAC, respectively. HPLC-DAD analysis revealed that radiation processing of grapes resulted in increased extraction of phenolic constituents in wine with no qualitative changes. No major radiation induced changes were observed in aroma constituents of wine. Sensory analysis revealed that 1500 Gy irradiated samples had higher fruity and berry notes. Thus, radiation processing of grapes resulted in wines with improved organoleptic and antioxidant properties. - Highlights: • Grapes were subjected to radiation processing before wine making. • Wines from irradiated grapes had higher antioxidant and phenolics compared to control. • HPLC analysis confirmed improved extraction of phenolics due to radiation processing. • Aroma profile and sensory quality of control and irradiated wines were similar

  11. Study on influence of irradiation vulcanization to silicon rubber autohesive tape's properties

    International Nuclear Information System (INIS)

    Chen Chun; Tang Jian; Wu Ling; Han Yingchun; Zhou Hong; Mo Yan; Fu Haijun

    2006-01-01

    After using 60 Co γ-ray to irradiate vulcanization silicon rubber autohesive tape, the effect of absorbed dose to the autohesive tape's tensile strength, elongation at break, autohesion and breakdown voltage strength and dose rate's effect to the autohesive tape's properties were studied. The results indicate that autohesive tape's tensile strength increases and the elongation at break decreases with the increasing dose. Under the dose of 25 kGy, the tape's autohesion increases with the increasing dose. When the dose is up to 25 kGy, the tape's autohesion achieves to the maximum, and then decreases with the increasing dose. Absorbed dose has no effect to the tape's breakdown voltage strength, and the dose rate has no effect to the autohesive tape's properties. (authors)

  12. Current Status of Radiation Processing of Natural Polymers in India

    International Nuclear Information System (INIS)

    Ramnani, S.P.

    2010-01-01

    Radiation processing is being used on commercial basis in India since 1974 with the operation of ISOMED plant for radiation sterilization of medical products and Electron beam machine (ILU-6) in 1986. Since then many new products and processes have been investigated and some of them have culminated into useful applications. Many Indian industries produce and process natural polymers for local consumption and export. India exports about 120,000 tons of polysaccharides every year. Natural polysaccharides like guar gum, gum acacia, gum tora, agar, psylium husk etc are treated with gamma radiation mainly for controlling microbial contamination and sterilization. Radiation processing has also been used to reduce molecular weight of the polysaccharides in some applications. Recently, a few new applications have emerged where natural polysaccharides are used as additives and which play important role in controlling basic radiation chemistry reactions to produce useful products. Developed at BARC, radiation processed wound dressings, superabsorbent materials and low molecular weight chitosan are the products which have been used and could find potential applications in health care and agriculture sector. Radiation processed hydrogel wound dressings containing natural polysaccharides have already been commercialized. Some of the applications recently developed at BARC using natural polymers are briefly described below

  13. Radiation dosimetry for commissioning Egypt's 'ega-gamma I' facility for radiation processing

    International Nuclear Information System (INIS)

    El-Behay, A.Z.; Rageh, S.I.; El-Assy, N.B.; Roushdy, H.

    1981-01-01

    The use of ionizing radiation for sterilization of medical products and biological tissues has become an alternative to autoclaving or gas treatment by ethylene oxide. Moreover, large radiation facilities are now increasing for processing many industrial products, such as rubber, textiles, plastics, coatings, films, wire and cable. For quality control of irradiated products released to the public, greater consideration is now being given to the use of physical radiation dosimetry, since it is simple, reliable, and reproducible. This work describes dosimetry for the new 60 Co irradiation plant, located at the National Center for Radiation Research and Technology of Egypt. Detailed measurements of absorbed dose extremes in product boxes processed in the plant were made using commercially supplied dyed plastic dosimeters (Red Acrylic and Red Perspex). These physical dosimeters were calibrated against the yield of cerous ion due to γ-ray irradiation of ceric sulphate solution as a standard chemical dosimeter. (author)

  14. The practice of safety culture construction in radiation processing enterprise

    International Nuclear Information System (INIS)

    Kong Xiangshan; Zhang Yue; Yang Bin; Xu Tao; Liu Wei; Hao Jiangang

    2014-01-01

    Security is an integral part of the process of business operations. The radiation processing enterprises due to their own particularity, more need to focus on the operation of the safety factors, the construction of corporate safety culture is of great significance in guiding carry out the work of the Radiation Protection. Radiation processing enterprises should proceed from their own characteristics, the common attitude of security systems and security construction, and constantly improved to ensure the personal safety of radiation workers in the area of safety performance. (authors)

  15. Radiation-thermal processes of conversion in the coals

    International Nuclear Information System (INIS)

    Mustafaev, I.I.

    2002-01-01

    Full text: The brief review, history, modern condition and bibliographic data on research of radiation-stimulated processes in coals are adduced in the report. Results of new researches of influence of gamma - radiation and accelerated electrons on pyrolysis, gasification, desulphurization, paramagnetism, adsorption and optical properties of coals in wide intervals of change of absorbed dose, dose rate, temperature, radiation type and other parameters of processes are stated. As object of researches Turkish (Yeni koy, Yatagan) and Russian (Siberia) coals were used. Specific peculiarities of influence of ionizing radiations on fossil fuels, bringing in change of their reactivity as result of destruction and polycondensation processes are considered. a)Pyrolysis: Under action of gamma-radiation and accelerated electrons the rate of thermal (t) pyrolysis grows and the ratio of radiation-thermal (rt) and thermal (t) processes: Wrt/ Wt depends on dose rate and temperature. By increase of dose rate the radiation effects grows, and at increase of temperature this effect is reduced. The influence of high rate heating of coals under pulls action of accelerated electrons on conversion degree and product composition has been established. The investigation regularities of formation liquid and gas products is resulted at radiation - thermal processing of mixtures of lignites with fuel oil. These experiments were conducted in flowing conditions in the interval of temperature T=350-500 degrees centigrade, power of the pulls accelerated electrons P=30-50 W, flow velocity of fuel oil 0,2-2 ml/minute. As a index of process were controlled conversion degree of coals, overall yield, contents and characteristic of liquid and gas products. The products of thermal treatment of these mixtures and also radiation-thermal treatment of separate components significantly less than radiation-thermal conversion of binary mixtures. It has been established that radiation effect has a positive

  16. Radiation processing in the plastics industry

    International Nuclear Information System (INIS)

    Saunders, C.B.

    1988-01-01

    The interaction of ionizing radiation with organic substrates to produce useful physical and chemical changes is the basis of the radiation processing industry for plastics. Electron beam (EB) accelerators dominate the industry; however, there are a few small applications that use gamma radiation. The five general product categories that account for over 95% of the worldwide EB capacity used for plastics production are the following: wire and cable insulation; heat-shrinkable film, tubes and pipes; radiation-curable coatings; rubber products; and polyolefin foam. A total of 6.1% of the yearly production of these products in the United States is EB treated. The United States accounts for 59% of the total worldwide EB capacity of 20.5 MW (1984), followed by Europe (16%) and Japan (15%). There are 469 to 479 individual EB units worldwide used for the production of plastics and rubber. The average annual rate of growth (AARG) for the EB processing of plastics in Japan, from 1977 to 1987, was 13.3%. The AARG for Japan has decreased from 20% for 1977 to 198, to 6.4% for 1984 to 1987. Radiation cross-linking, of power cable insulation (cable rating ≥75 kV), thick polyolefin and rubber sheet (≥15 mm), and thick-walled tubing is one fo the potential applications for a 5- to 10-MeV EB system. Other products such as coatings, films and wire insulation may be economically EB-treated using a 5 to 10 MeV accelerator, if several layers of the product could be irradiated simultaneously. Two general product categories that require more study to determine the potential of high-energy EB processing are moulded plastics and composite materials. 32 refs

  17. A new radiochromic film for radiation processing

    International Nuclear Information System (INIS)

    Sidney, L.N.; Lynch, D.C.; Willett, P.S.; Englund, W.J.

    1990-01-01

    Acid-sensitive leuco dyes in combination with a chlorine-containing polymer have been used to make a new kind of radiochromic film for radiation processing. When exposed to gamma, electron beam, or high intensity ultraviolet radiation, these films undergo a color change from colorless to royal blue, fuschia, or black, depending on the dye. The dose response for gamma and electron beam radiation has been characterized using reflection and transmission spectrophotometry over an adsorbed dose range of 1 to 100 kGy. The primary features of the films include improved color stability before and after irradiation and improved moisture resistance. The response and stability of the films make them useful for indicator (qualitative) or dosimeter (quantitative) films or labels for sterilization of medical products, food (especially meat, poultry, and spices), pharmaceuticals, and cosmetics, and the crosslinking of plastics, and the curing of polymer coatings. Large pieces of the film could be used in dose mapping when setting up and validating radiation processes and medical treatments

  18. Elastomeric Nanocomposite Based on Exfoliated Graphene Oxide and Its Characteristics without Vulcanization

    Directory of Open Access Journals (Sweden)

    Nasser Abdullah Habib

    2017-01-01

    Full Text Available Rubber nanocomposites have emerged as one of the advanced materials in recent years. The aim of this work was to homogeneously disperse graphene oxide (GO sheets into Nitrile Butadiene Rubber (NBR and investigate the characteristics of GO/NBR nanocomposite without vulcanization. A suitable solvent was found to dissolve dry NBR while GO was exfoliated completely in an aqueous base solution using sonication. GO was dispersed into NBR at different loadings by solution mixing to produce unvulcanized GO/NBR nanocomposites. Scanning Electron Microscopy (SEM, Fourier-Transform Infrared Spectroscopy (FTIR, and X-Ray Diffraction (XRD were used to characterize the samples. Furthermore, mechanical and electrical properties of unvulcanized GO/NBR nanocomposites were carried out to determine the influence of GO on the NBR properties. The results showed that the modulus of GO/NBR nanocomposite at 1 wt% of GO was enhanced by about 238% compared with unfilled NBR. These results provide insight into the properties of unvulcanized GO/NBR nanocomposite for application as coatings or adhesives.

  19. Radiation processing of dry food ingredients - a review

    International Nuclear Information System (INIS)

    Farkas, J.

    1985-01-01

    Radiation decontamination of dry ingredients, herbs and enzyme preparations is a technically feasible, economically viable and safe physical process. The procedure is direct, simple, requires no additives, does not leave residues and is highly efficient. Its dose requirement is moderate. Radiation doses of 3 to 10 kGy proved to be sufficient to reduce the viable cell counts to a satisfactory level. Ionizing radiations do not cause any significant rise in temperature and the flavour, texture or other important technological or sensory properties of most ingredients are not influenced at radiation doses necessary for a satisfactory decontamination. The microflora surviving the cell-count reduction by irradiation is more sensitive to subsequent food processing treatments than the microflora of untreated ingredients. Recontamination can be prevented since the product can be irradiated in its final packaging. Irradiation can be carried out in commercial containers and it results in considerable savings of energy and labour as compared to alternative decontamination techniques. Radiation processing of dry ingredients is an emerging technology in several countries and more and more clearances on irradiated foods are issued or expected to be granted in the near future. (author)

  20. Radiation processing of dry food ingredients - a review

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, J

    1985-01-01

    Radiation decontamination of dry ingredients, herbs and enzyme preparations is a technically feasible, economically viable and safe physical process. The procedure is direct, simple, requires no additives, does not leave residues and is highly efficient. Its dose requirement is moderate. Radiation doses of 3 to 10 kGy proved to be sufficient to reduce the viable cell counts to a satisfactory level. Ionizing radiations do not cause any significant rise in temperature and the flavour, texture or other important technological or sensory properties of most ingredients are not influenced at radiation doses necessary for a satisfactory decontamination. The microflora surviving the cell-count reduction by irradiation is more sensitive to subsequent food processing treatments than the microflora of untreated ingredients. Recontamination can be prevented since the product can be irradiated in its final packaging. Irradiation can be carried out in commercial containers and it results in considerable savings of energy and labour as compared to alternative decontamination techniques. Radiation processing of dry ingredients is an emerging technology in several countries and more and more clearances on irradiated foods are issued or expected to be granted in the near future.

  1. Technological yields of sources for radiation processing

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1990-01-01

    The present report is prepared for planners of radiation processing of any material. Sources with cobalt-60 are treated marginally, because most probably, there will be no installation of technically meaningful activity in Poland before the year 2000. Calculations are focused on accelerators of electrons, divided into two groups: versatile linacs of energy up to 13 MeV and accelerators of lower energy, below 2 MeV, of better energetical yield but of limited applications. The calculations are connected with the confrontation of the author's technological expectations during the preparation of the linac project in the late '60s, with the results of twenty years of exploitation of the machine. One has to realize that from the 150 kV input power from the mains, only 5 kV of bent and scanned beam is recovered on the conveyor. That power is only partially used for radiation induced phenomena, sometimes only a few percent, because of the demanded homogeneity of the dose, of the mode of packing of the object and its shape, of losses at the edges of the scanned area and in the spaces between boxes, and of losses during the dead time due to the tuning of the machine and dosimetric operations. The use of lower energy accelerators may be more economical in case of objects of optimum type. At the first stage, that is of the conversion of electrical power into that of the low energy electron beam, the yield is 2-3 times better than in the case of linacs. Attention has been paid to the technological aspects of electron beam conversion into the more penetrating bremsstrahlung similar to gamma radiation. The advantages of these technologies, which make it possible to control the shape of the processed object are stressed. Ten parameters necessary for a proper calculation of technological yields of radiation processing are listed. Additional conditions which must be taken into account in the comparison of the cost of radiation processing with the cost of other technologies are also

  2. Radiation processing of food to ensure food safety and security

    International Nuclear Information System (INIS)

    Gautam, Satyendra

    2016-01-01

    Radiation processing of food utilizes the controlled application of energy from ionizing radiations such as γ-rays , electrons and X-rays on food. Gamma-rays and X-rays are short wavelength radiations of the electromagnetic spectrum. The approved sources of gamma radiation for food processing are radioisotopes (Cobalt-60 and Caesium-137), electron beam (up to 10 MeV) and X-rays (up to 5 MeV) wherein the latter two are generated by machines using electricity. γ-radiation can penetrate deep into the food materials causing the desired effects. Irradiation works by disrupting the biological processes that lead to decay. While interacting with water and other biomolecules that constitute the food and living organisms, radiation energy is absorbed by these molecules. The interactions of radiation and radiolytic products of water with DNA impair the reproduction of microorganism and insects, and thus help in achieving the desired objectives pertaining to food safety and security

  3. Radiation processing of natural polymer in Malaysia

    International Nuclear Information System (INIS)

    Khairul Zaman; Kamaruddin Hashim; Zulkafli Ghazali; Mohd Hilmi Mahmood; Dahlan Hj. Mohd; Jamaliah Sharif

    2007-01-01

    Research on radiation processing of natural polymer has been carried out by Nuclear Malaysia since 10 years ago. The progress of the research is at various stages. Radiation processing of sago hydrogel has been commercialized. Meanwhile ago film for packaging is at the pilot scale trial. Palm oil products are ready to be further developed for commercialization with any interested industrial partner. On the other hand, some new materials are being developed based on natural rubber such as liquid natural as compatibilizer, natural rubber thermoplastic nanoclay composites and natural rubber magnetic nano particles composites. (author)

  4. 21 CFR 179.39 - Ultraviolet radiation for the processing and treatment of food.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ultraviolet radiation for the processing and..., PROCESSING AND HANDLING OF FOOD Radiation and Radiation Sources § 179.39 Ultraviolet radiation for the processing and treatment of food. Ultraviolet radiation for the processing and treatment of food may be...

  5. One of the great conundrums of the 20th century science - ionizing radiation: Radiation processing and applications in the Czech Lands

    International Nuclear Information System (INIS)

    Janovsky, I.

    2007-01-01

    The article deals with the following topics: Milestones in the early history of radiation and radiation sources (1895-1954); Radiation effects - early observations and further development; Scope of radiation processing; Radiation processing in the Czech Lands (i.e. Bohemia + Moravia = the Czech part of Czechoslovakia or Austria-Hungary till 1918) (radiation sterilization of medical items; radiation processing of cable insulations; radiation preservation of objects of art and historical monuments; radiation modification of semiconductors; radiation synthesis of organic compounds; food irradiation; application of ionizing radiation in agriculture and gardening; radiation regeneration of water wells; radiation degradation of chlorinated biphenyls; radiation coloration of glass for decorative purposes; some other applications; and problems associated with practical radiation processing). An overview of 60 Co gamma irradiators and electron accelerators installed at Czech institutions is presented in the tabular form. (P.A.)

  6. Achievements and perspectives for radiation processing

    International Nuclear Information System (INIS)

    Charlcsby, A.

    1992-01-01

    In the last few decades the major practical applications of large radiation sources have been in the irradiation of macromolecular systems. These have risen rapidly to annual outputs of billions of dollars and continue to show steady growth. In other directions such as polymerization and grafting, radiation has been less successful, primarily because in these subjects radiation serves as only one step in a sequence of chemical reactions, and often these can be achieved by more conventional and familiar methods. We envisage future progress along several distinct lines. 1. Reduction in the cost of radiation. 2. The application of radiation technology in areas where valuable modifications are involved and where advantage can be taken of the remarkable control offered by electron beams. 3. Areas where the chemical alternatives do not exist or are difficult to apply. 4. A very different line of approach is to use radiation with its far more complete control and reproducibility to investigate many processes even if in the production stage itself a different technique is later utilized. Present examples are chemical kinetics as with ESR, pulse radiolysis, pulsed NMR, behavior of trapped charges, crystal structure, local modifications, reinforcement and orientation etc. (J.P.N.)

  7. Characterization of 10 MeV electron linac for radiation processing

    International Nuclear Information System (INIS)

    Petwal, V.C.; Rao, J.N.; Kaul, A.; Bapna, S.C.; Mulchandani, J.K.; Wanmode, Y.; Pandiyar, M.; Srivastava, P.; Jain, Akhilesh; Hanurkar, P.R.

    2006-01-01

    A radiation processing facility based on a 10 MeV LINAC is being set-up at RRCAT. In the course of commissioning various experiments have been carried-out to characterize the radiation field generated by the accelerator and subsequently to derive the operating parameters of the facility for radiation processing of various items. Results of the experiments are presented in the paper. (author)

  8. Thermal characterization of radiation processed contact lens material

    International Nuclear Information System (INIS)

    Varshney, L.; Choughule, S.V.

    1998-01-01

    Differential scanning calorimetry (DSC), thermomechanical analysis (TMA) and thermogravimetry analysis (TGA) were used to characterize radiation processed contact lens gel material of 2-hydroxy ethyl methacrylate(HEMA). DSC revealed two types of water in the gels. DSC and TGA in combination were used to quantitate the percentage of different types of the water in the gel material. Temperature expansion coefficients values indicate more dimensions stability in the radiation processed lenses of similar water contents. (author)

  9. Radiation in industrial processes;Applications reviewed at Warsaw Conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1959-10-15

    The uses of ionizing radiation can be divided into two broad categories. First, it can be used as a tool of investigation, measurement and testing, and secondly, it can be a direct agent in inducing chemical processes. For example, radiation can help in the detecting and locating of malignant tumours, and it can be employed also for the destruction of those tumours. Again, it can reveal intricate processes of plant growth and, at the same time, can initiate certain processes which result in the growth of new varieties of plants. Similarly in industry, radiation is both a tool of detection, testing and measurement and an active agent for the initiation of useful chemical reactions. The initiation of chemical reactions usually requires larger and more powerful sources of radiation. Such radiation can be provided by substances like cobalt 60 and caesium 137 or by machines which accelerate nuclear particles to very high energies. Of the particle-accelerating machines, the most useful in this field are those which accelerate electrons to energies considerably higher than those possessed by the electrons (beta particles) emitted by radioactive substances. These high-energy radiations produce interesting reactions both in organic life and in materials for industry. Several of the papers presented at the Warsaw conference were devoted to the application of ionizing radiation to polymerization and other useful reactions in the manufacture and treatment of plastics. The polymerization of the ethylene series of hydro-carbons was discussed from various angles and the technical characteristics and requirements were described. It was pointed out by some experts that the cross-linking effect of radiation resulted in a superior product, opening the way to new applications of polyethylene. Irradiated polyethylene film has been sold for several years, and electrical wire has been made with irradiated polyethylene as the insulating jacket. Other reactions discussed included the cross

  10. Parton radiative processes and pressure isotropization in relativistic heavy ion collisions

    International Nuclear Information System (INIS)

    Zhang, Bin; Wortman, Warner A.

    2010-01-01

    The impact of radiative processes on kinetic equilibration is studied via a radiative transport model. The 2↔3 processes can significantly increase the level of thermalization. These processes lead to an approximate coupling constant scaling of the evolution of the pressure anisotropy qualitatively different from the case with only 2→2 partonic processes. Furthermore, thermal and Color Glass Condensate motivated initial conditions are shown to share the same asymptotic evolution when 2↔3 processes are included. This emphasizes the unique role of radiative processes in Quark-Gluon Plasma thermalization.

  11. About Solar Radiation Intensity Measurements and Data Processing

    Directory of Open Access Journals (Sweden)

    MICH-VANCEA Claudiu

    2012-10-01

    Full Text Available Measuring the intensity of solar radiation is one of the directions of investigation necessary for the implementation of photovoltaic systems in a particular geographical area. This can be done by using specific measuring equipment (pyranometer sensors based onthermal or photovoltaic principle. In this paper it is presented a method for measuring solar radiation (which has two main components - direct radiation and diffuse radiation with sensors based on photovoltaic principle. Such data are processed for positioning solarpanels, in order their efficiency to be maximized.

  12. Manual of radiation processing of cassava starch hydrogel

    International Nuclear Information System (INIS)

    Sonsuk, Manit

    2007-01-01

    The radiation processing of natural cassava starch (CS) is described for the improvement of its properties. A series of hydrogels were prepared from gelatinized CS and vinylpyrrolidone by radiation-induced graft copolymerization. Hydrogels were also synthesized from radiation-induced crosslinking of carboxymethyl CS. The optimum condition for the swelling ratio and gel fraction of the obtained hydrogels is irradiation at low dose. The polymeric chelating resins containing the hydroxamic acid groups were synthesized from the polymethyl acrylate (PMA)-grafted CS via gamma radiation. (M.H.)

  13. A typical R and D center on radiation processing in China

    International Nuclear Information System (INIS)

    Sun Jlazhen

    1995-01-01

    The industrial application of radiation processing has been growing rapidly in China since 1980s in such fields as producing radiation-crosslinked heat shrinkable materials and radiation-crosslinked wires and cables, sterilization of medical products and so on. Changchun Institute of Applied Chemistry (CIAC) as one of the earliest organizations in which the fundamental research works on polymer radiation chemistry have been carried out has played a major role for the R and D of the radiation processing of polymers. From the R and D activities at CIAC, it can be seen how a Chinese research institute transfers its results of fundamental research works into large scale production. The improvement of the weakness of fluoropolymers by radiation crosslinking, the modification of the Charlesby-Pinner equation that describes the relationship of sol fraction to irradiation dose, the radiation grafting for preparing functional materials, the radiation crosslinking of polymer blends and the effect of antioxidant on the radiation crosslinking of polymers are reported. Also applied research works and the radiation processing at CIAC are described. (K.I.)

  14. A commercial multipurpose radiation processing facility for Hawaii

    International Nuclear Information System (INIS)

    Welt, M.A.

    1985-01-01

    The State of Hawaii offers a unique challenge for the designer of an economically feasible radiation processing system. Based on the prevailing agricultural export requirements, the radiation facility must be capable for handling a variety of bulky fruit and vegetable products for insect disinfestation purposes and, yet, provide proper economies for the users of the facility. A capability must exist for irradiating other types of products requiring higher doses, e.g., fish and shellfish products for shelf-life extension, which might require a dose approximately eight times higher than the disinfestation dose, or even medical product or a food sterilization dose, which would be approximately twelve times higher than the required shelf-life extension dose. The Radiation Technology Model RT 4l0l-4048 radiation processing facility provides the necessary versatility and operational reliability to meet the challenge. The technical features and economic analyses demonstrate the advantages of this computer-operated pallet irradiation system. Actual performance data from the Radiation Technology subsidiary operations in West Memphis, Arkasas, and Burlilngton, North Carolina, are presented along with photographs of the proposed system for Hawaii

  15. Influence of the dose rate in the PVDF degradation processes

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Adriana S.M.; Pereira, Claubia, E-mail: adriananuclear@yahoo.com.br, E-mail: claubia@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Gual, Maritza R., E-mail: maritzargual@gmail.com [Instituto Superior de Tecnologias y Ciencias Aplicadas (InsTEC), Departamento de Ingenieria Nuclear, La Habana (Cuba); Faria, Luiz O., E-mail: farialo@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    Modification in polymeric structure of plastic material can be brought either by conventional chemical means or by exposure to ionization radiation from gamma radioactive sources or highly accelerated electrons. The prominent drawbacks of chemical cross-linking typically involve the generation by products such as peroxide degradation. Radiation cross-linking technologies include: application in cable and wire, application in rubber tyres, radiation vulcanization of rubber latex, polymer recycling, hydrogels etc. The degradation of PVDF polymer exposed to gamma irradiation in oxygen atmosphere in high dose rate has been studied and compared to obtained under smaller dose rates. The samples were irradiated with a Co-60 source at constant dose rate (12 kGy/h and 2,592 kGy/h), with doses ranging from 100 kGy to 3,000 kGy. Different dose rate determine the prevalence of the processes being evaluated in this work by thermal measurements and infrared spectroscopy. It is shown that the degradation processes involve chain scissions and crosslink formation. The formation of oxidation products was shown at the surface of the irradiated film. The FTIR data revealed absorption bands at 1730 and 1853 cm{sup -1} which were attributed to the stretch of C=O bonds, at 1715 and 1754 cm{sup -1} which were attributed to the C=C stretching and at 3518, 3585 and 3673 cm{sup -1} which were associated with NH stretch of NH{sub 2} and OH. Thermogravimetric studies reveal that the irradiation induced the increasing residues and decrease of the temperature of the decomposition start. (author)

  16. Influence of the dose rate in the PVDF degradation processes

    International Nuclear Information System (INIS)

    Batista, Adriana S.M.; Pereira, Claubia; Gual, Maritza R.; Faria, Luiz O.

    2015-01-01

    Modification in polymeric structure of plastic material can be brought either by conventional chemical means or by exposure to ionization radiation from gamma radioactive sources or highly accelerated electrons. The prominent drawbacks of chemical cross-linking typically involve the generation by products such as peroxide degradation. Radiation cross-linking technologies include: application in cable and wire, application in rubber tyres, radiation vulcanization of rubber latex, polymer recycling, hydrogels etc. The degradation of PVDF polymer exposed to gamma irradiation in oxygen atmosphere in high dose rate has been studied and compared to obtained under smaller dose rates. The samples were irradiated with a Co-60 source at constant dose rate (12 kGy/h and 2,592 kGy/h), with doses ranging from 100 kGy to 3,000 kGy. Different dose rate determine the prevalence of the processes being evaluated in this work by thermal measurements and infrared spectroscopy. It is shown that the degradation processes involve chain scissions and crosslink formation. The formation of oxidation products was shown at the surface of the irradiated film. The FTIR data revealed absorption bands at 1730 and 1853 cm -1 which were attributed to the stretch of C=O bonds, at 1715 and 1754 cm -1 which were attributed to the C=C stretching and at 3518, 3585 and 3673 cm -1 which were associated with NH stretch of NH 2 and OH. Thermogravimetric studies reveal that the irradiation induced the increasing residues and decrease of the temperature of the decomposition start. (author)

  17. Radiation decontamination of dry food ingredients and processing aids

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, J

    1984-01-01

    Radiation decontamination of dry ingredients, herbs and enzyme preparations is a technically feasible, economically viable and safe physical process. The procedure is direct, simple, requires no additives and is highly efficient. Its dose requirement is moderate. Radiation doses of 3-10 kGy (0.3-1 mrad) have proved sufficient to reduce the viable counts to a satisfactory level. Ionising radiations do not cause any significant rise in temperature. The flavour, texture or other important technological or sensory properties of most ingredients are not influenced at radiation doses necessary for satisfactory decontamination, and radiation obviates the chemical residue problem. The microflora surviving radiation decontamination of dry ingredients are more susceptible to subsequent antimicrobial treatments. Recontamination can be prevented as the product can be irradiated in its final packaging. Irradiation could be carried out in commercial containers and would result in considerable savings of energy and labour as compared to alternative decontamination techniques. Radiation processing of these commodities is an established technology in several countries and more clearances on irradiated foods are expected to be granted in the near future.

  18. Improving degradation of paracetamol by integrating gamma radiation and Fenton processes.

    Science.gov (United States)

    Cruz-González, Germán; Rivas-Ortiz, Iram B; González-Labrada, Katia; Rapado-Paneque, Manuel; Chávez-Ardanza, Armando; Nuevas-Paz, Lauro; Jáuregui-Haza, Ulises J

    2016-10-14

    Degradation of paracetamol (N-(4-hydroxiphenyl)acetamide) in aqueous solution by gamma radiation, gamma radiation/H2O2 and gamma radiation/Fenton processes was studied. Parameters affecting the radiolysis of paracetamol such as radiation dose, initial concentration of pollutant, pH and initial oxidant concentration were investigated. Gamma radiation was performed using a (60)Co source irradiator. Paracetamol degradation and mineralization increased with increasing absorbed radiation dose, but decreased with increasing initial concentration of the drug in aqueous solution. The addition of H2O2 resulted in an increased effect on irradiation-driven paracetamol degradation in comparison with the performance of the irradiation-driven process alone: paracetamol removal increased from 48.9% in the absence of H2O2 to 95.2% for H2O2 concentration of 41.7 mmol/L. However, the best results were obtained with gamma radiation/Fenton process with 100% of the drug removal at 5 kGy, for optimal H2O2 and Fe(2+) concentrations at 13.9 and 2.3 mmol/L, respectively, with a high mineralization of 63.7%. These results suggest gamma radiation/H2O2 and gamma radiation/Fenton processes as promising methods for paracetamol degradation in polluted wastewaters.

  19. Controlling of degradation effects in radiation processing of polymers

    International Nuclear Information System (INIS)

    2009-05-01

    The interest of Member States of the IAEA in introducing radiation technology into the polymer and plastics industry is growing. This publication summarizes a number of studies conducted in the framework of a coordinated research project (CRP) on controlling of degradation effects on polymers by radiation processing technologies. It reviews a variety of applications and details the most important results and achievements of the participating centres and laboratories during the course of the CRP. The publication is intended to be of use to scientists implementing the technology and managers of radiation processing facilities

  20. Advancements in internationally accepted standards for radiation processing

    International Nuclear Information System (INIS)

    Farrar, H. IV; Derr, D.D.; Vehar, D.W.

    1993-01-01

    Subcommittees of the American Society for Testing and Materials (ASTM) are developing standards on various aspects of radiation processing. Nine standards on how to select and calibrate dosimeters, where to put them, how many to use, and how to use individual types of dosimeter systems have been published. The group is also developing standards on how to use gamma, electron beam, and X-ray facilities for radiation processing, and a standard on how to treat dose uncertainties. Efforts are underway to promote inclusion of these standards into procedures now being developed by government agencies and by international groups such as the United Nations' International Consultative Group on Food Irradiation (ICGFI) in order to harmonize regulations and help avoid trade barriers. Standards on good irradiation practices for meat and poultry and for fresh fruits, and for the irradiation of seafood and spices have been developed. These food-related standards are based on practices previously published by ICGFI. Standards for determining doses for radiation hardness testing of electronics have been developed. Standards on the Fricke and TLD dosimetry systems are equally useful in other radiation processing applications. (Author)

  1. Radiation sources and process

    International Nuclear Information System (INIS)

    Honious, H.B.; Janzow, E.F.; Malson, H.A.; Moyer, S.E.

    1980-01-01

    The invention relates to radiation sources comprising a substrate having an electrically-conductive non-radioactive metal surface, a layer of a metal radioactive isotope of the scandium group, which in addition to scandium, yttrium, lanthanum and actinium, includes all the lanthanide and actinide series of elements, with the actinide series usually being preferred because of the nature of the radioactive isotopes therein, particularly americium-241, curium-244, plutonium-238, californium-252 and promethium-147, and a non-radioactive bonding metal codeposited on the surface by electroplating the isotope and bonding metal from an electrolytic solution, the isotope being present in the layer in minor amount as compared to the bonding metal, and with or without a non-radioactive protective metal coating covering the isotoype and bonding metal on the surface, the coating being sufficiently thin to permit radiation to pass through the coating. The invention also relates to a process for providing radiation sources comprising codepositing a layer of the metal radioactive isotope with a non-radioactive bonding metal from an electrolytic solution in which the isotope is present in minor molar amount as compared to the bonding metal such that the codeposited layer contains a minor molar amount of the isotope compared to the bonding metal by electroplating on an electrically-conductive non-radioactive metal surface of a cathode substrate, and with or without depositing a nonradioactive protective metal coating over the isotope and bonding metal on the surface, the coating being sufficiently thin to permit radiation to pass through the coating

  2. A novel coating strategy towards improving interfacial adhesion strength of Cu–Sn alloy coated steel with vulcanized rubber

    International Nuclear Information System (INIS)

    Banerjee, Atanu; Dutta, Monojit; Bysakh, Sandip; Bhowmick, Anil K.; Laha, Tapas

    2014-01-01

    Highlights: • We propose a double layer Cu–Sn alloy coating strategy on steel to improve adhesion. • Uniform coating with adequate penetration inside micro-roughness was observed. • XPS and GDOES study revealed improved substrate surface coverage by coating. • TEM investigation confirmed compact, uniform and micro-porosity free interface. • Peel test with vulcanized rubber confirmed improved adhesion with cohesive fracture. - Abstract: A comparative assessment in terms of uniformity, coating coverage and coating deposition mechanism has been carried out for two different types of Cu–Sn coatings on steel substrate with varying Sn composition (2–6.5 wt%) deposited via immersion technique, viz. (i) single layer Cu–Sn coating and (ii) double layer coating consisting of a thin Cu strike layer followed by a Cu–Sn layer. Coating morphology, surface coverage, coating-substrate interface, and coating composition at surface and along the depth were studied using laser confocal microscope (OLS), scanning electron microscope (SEM) coupled with energy dispersive spectroscope (EDS), glow discharge optical emission spectroscopy (GDOES), X-ray photoelectron spectroscopy (XPS) and cross-sectional transmission electron microscopy (TEM). Quantitative depth profiling using GDOES and surface compositional analysis via XPS suggested improvement in surface coverage in the case of double layer coatings. SEM-EDS and TEM analysis confirmed that the coating deposition was more uniform with sufficient coating penetration inside the deep roughness troughs resulting in compact and micro-porosity free interface for this type of coatings. Better adhesion strength with less variation in peel force and cohesive mode of fracture within the rubber was observed for the double layer coated samples during the peel test carried out on coated steel samples vulcanized with rubber. On the other hand, the single layer coated samples showed large variation in peel force with adhesive

  3. A novel coating strategy towards improving interfacial adhesion strength of Cu–Sn alloy coated steel with vulcanized rubber

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Atanu [Tata Steel, Jamshedpur 831001 (India); Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Kharagpur 721302 (India); Dutta, Monojit [Tata Steel, Jamshedpur 831001 (India); Bysakh, Sandip [Central Glass and Ceramic Research Institute, Kolkata 700032 (India); Bhowmick, Anil K. [Rubber Technology Center, Indian Institute of Technology, Kharagpur 721302 (India); Laha, Tapas, E-mail: laha@metal.iitkgp.ernet.in [Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Kharagpur 721302 (India)

    2014-09-15

    Highlights: • We propose a double layer Cu–Sn alloy coating strategy on steel to improve adhesion. • Uniform coating with adequate penetration inside micro-roughness was observed. • XPS and GDOES study revealed improved substrate surface coverage by coating. • TEM investigation confirmed compact, uniform and micro-porosity free interface. • Peel test with vulcanized rubber confirmed improved adhesion with cohesive fracture. - Abstract: A comparative assessment in terms of uniformity, coating coverage and coating deposition mechanism has been carried out for two different types of Cu–Sn coatings on steel substrate with varying Sn composition (2–6.5 wt%) deposited via immersion technique, viz. (i) single layer Cu–Sn coating and (ii) double layer coating consisting of a thin Cu strike layer followed by a Cu–Sn layer. Coating morphology, surface coverage, coating-substrate interface, and coating composition at surface and along the depth were studied using laser confocal microscope (OLS), scanning electron microscope (SEM) coupled with energy dispersive spectroscope (EDS), glow discharge optical emission spectroscopy (GDOES), X-ray photoelectron spectroscopy (XPS) and cross-sectional transmission electron microscopy (TEM). Quantitative depth profiling using GDOES and surface compositional analysis via XPS suggested improvement in surface coverage in the case of double layer coatings. SEM-EDS and TEM analysis confirmed that the coating deposition was more uniform with sufficient coating penetration inside the deep roughness troughs resulting in compact and micro-porosity free interface for this type of coatings. Better adhesion strength with less variation in peel force and cohesive mode of fracture within the rubber was observed for the double layer coated samples during the peel test carried out on coated steel samples vulcanized with rubber. On the other hand, the single layer coated samples showed large variation in peel force with adhesive

  4. Study of properties of chloroprene rubber devulcanizate by radiation in microwave

    International Nuclear Information System (INIS)

    Scagliusi, Sandra R.; Araujo, Sumair G.; Landini, Liliane; Lugao, Ademar B.

    2009-01-01

    Among the vulcanized elastomers, the chloroprene rubber (DuPont Neoprene R - generic name) possesses a good performance, being one of the most used in the current days. However, this kind of polymer causes a serious environmental problem if it is not reprocessed or recycled. A worldwide method that has been used and that is an important tool in the rubber devulcanization is microwave irradiation at high temperature Elastomer waste may be devulcanized without depolymerization and allows a new vulcanization into a product having physical properties essentially equivalent to the original vulcanized. In this work, the chloroprene samples were irradiated in microwave generator equipment with 2,450 MHz (frequency) and 1,000 W to 3,000 W (power). The properties of samples (according to ASTM standards) were analyzed before and after irradiation. The degraded material after irradiation will be tested for re-use. (author)

  5. Computer models of dipole magnets of a series 'VULCAN' for the ALICE experiment

    International Nuclear Information System (INIS)

    Vodop'yanov, A.S.; Shishov, Yu.A.; Yuldasheva, M.B.; Yuldashev, O.I.

    1998-01-01

    The paper is devoted to a construction of computer models for three magnets of the 'VULCAN' series in the framework of a differential approach for two scalar potentials. The distinctive property of these magnets is that they are 'warm' and their coils are of conic saddle shape. The algorithm of creating a computer model for the coils is suggested. The coil field is computed by Biot-Savart law and a part of the integrals is calculated with the help of analytical formulas. To compute three-dimensional magnetic fields by the finite element method with a local accuracy control, two new algorithms are suggested. The former is based on a comparison of the fields computed by means of linear and quadratic shape functions. The latter is based on a comparison of the field computed with the help of linear shape functions and a local classical solution. The distributions of the local accuracy control characteristics within a working part of the third magnet and the other results of the computations are presented

  6. Role of BRIT in promoting radiation processing technology in India

    International Nuclear Information System (INIS)

    Bandi, L.N.

    2014-01-01

    Some of the major applications of radiation processing include: the sterilization of products such as medical devices to kill bacteria or in the case of food, hygienize the product; the treatment of export bulk commodities such as tropical fruits to extend shelf life by slowing the ripening process and inhibiting sprouting and to kill quarantine pests such as fruit flies. Radiation processing is a value addition process. Taking note of these benefits, Department of Atomic Energy, Government of India constituted Board of Radiation and Isotope Technology (BRIT) in March 1989 by carving it out from Bhabha Atomic Research Centre, Mumbai. The mandate given to BRIT was to extend commercial applications of radioisotopes and radiation in the areas of Health, Agriculture, Industry and Research without losing sight of societal obligations. So far Department of Atomic Energy has set up three demonstration plants, namely, Isomed, RPP, Vashi and Krushak for high, medium and low dose applications of radiation respectively. The safe and business like operation of these facilities amply demonstrated the embedded safety and commercial viability of this technology

  7. Effectiveness of radiation processing for elimination of Salmonella Typhimurium from minimally processed pineapple (Ananas comosus Merr.).

    Science.gov (United States)

    Shashidhar, Ravindranath; Dhokane, Varsha S; Hajare, Sachin N; Sharma, Arun; Bandekar, Jayant R

    2007-04-01

    The microbiological quality of market samples of minimally processed (MP) pineapple was examined. The effectiveness of radiation treatment in eliminating Salmonella Typhimurium from laboratory inoculated ready-to-eat pineapple slices was also studied. Microbiological quality of minimally processed pineapple samples from Mumbai market was poor; 8.8% of the samples were positive for Salmonella. D(10) (the radiation dose required to reduce bacterial population by 90%) value for S. Typhimurium inoculated in pineapple was 0.242 kGy. Inoculated pack studies in minimally processed pineapple showed that the treatment with a 2-kGy dose of gamma radiation could eliminate 5 log CFU/g of S. Typhimurium. The pathogen was not detected from radiation-processed samples up to 12 d during storage at 4 and 10 degrees C. The processing of market samples with 1 and 2 kGy was effective in improving the microbiological quality of these products.

  8. Install and operate type radiation processing plant for marine products

    Energy Technology Data Exchange (ETDEWEB)

    Kohli, A.K. [BARC-BTIR Complex, Mumbai (India). Dept. of Atomic Energy. Board of Radiation and Isotope Technology

    2002-07-01

    Marine products can be carrier of several pathogens. Radiation processing is a very useful technique that is used to eliminate pathogens and also to extend shelf life of fresh fish. For marine products three processes are involved namely: radurization to pasteurize fresh chilled fish for extending shelf life; radicidation to sanitize frozen fishery products by elimination of pathogenic microorganisms and radiation disinfestations to eliminate insects from dehydrated fishery products. The paper brings out conceptual design of a compact radiation processing plant that can cater to all the three processes. The design is different from conveyor type of designs. The design is specially configured to maintain the temperature of frozen products and overdose ratio within limits specified. The throughput depends upon the source strength, type of product, the size of box and its configuration in which these could be arranged. The design has many features, which make it a very safe, convenient and economical method for processing of such items or for that matter all the food products, which are amenable for radiation processing. (author)

  9. International cooperative effort to establish dosimetry standardization for radiation processing

    International Nuclear Information System (INIS)

    Farrar, H. IV.

    1989-01-01

    Radiation processing is a rapidly developing technology with numerous applications in food treatment, sterilization, and polymer modification. The effectiveness of the process depends, however, on the proper application of dose and its measurement. These aspects are being considered by a wide group of experts from around the world who have joined together to write a comprehensive set of standards for dosimetry for radiation processing. Originally formed in 1984 to develop standards for food processing dosimetry, the group has now expanded into a full subcommittee of the American Society for Testing and Materials (ASTM), with 97 members from 19 countries. The scope of the standards now includes dosimetry for all forms of radiation processing. The group has now completed and published four standards, and is working on an additional seven. Three are specifically for food applications and the others are for all radiation applications, including food processing. Together, this set of standards will specify acceptable guidelines and methods for accomplishing the required irradiation treatment, and will be available for adoption by national regulatory agencies in their procedures and protocols. 1 tab

  10. Install and operate type radiation processing plant for marine products

    International Nuclear Information System (INIS)

    Kohli, A.K.

    2002-01-01

    Marine products can be carrier of several pathogens. Radiation processing is a very useful technique that is used to eliminate pathogens and also to extend shelf life of fresh fish. For marine products three processes are involved namely: radurization to pasteurize fresh chilled fish for extending shelf life; radicidation to sanitize frozen fishery products by elimination of pathogenic microorganisms and radiation disinfestations to eliminate insects from dehydrated fishery products. The paper brings out conceptual design of a compact radiation processing plant that can cater to all the three processes. The design is different from conveyor type of designs. The design is specially configured to maintain the temperature of frozen products and overdose ratio within limits specified. The throughput depends upon the source strength, type of product, the size of box and its configuration in which these could be arranged. The design has many features, which make it a very safe, convenient and economical method for processing of such items or for that matter all the food products, which are amenable for radiation processing. (author)

  11. Radiation processing of food and agricultural commodities

    International Nuclear Information System (INIS)

    Sharma, Arun

    2014-01-01

    Reducing post-harvest food losses is becoming increasingly important for sustaining food supplies. Appropriate post-harvest processing, handling, storage and distribution practices are as important as the efforts to increase productivity for improving food security, food safety and international trade in agricultural commodities. Preservation of food by ionizing radiation involves controlled application of energy of ionizing radiation such as gamma rays, X-rays, and accelerated electrons to agricultural commodities, food products and ingredients, for improving their storage life, hygiene and safety. The process employs either gamma rays emitted by radioisotopes such as cobalt-60 or high-energy electrons or X-rays generated from machine sources

  12. Radiations from atomic collision processes

    International Nuclear Information System (INIS)

    Bernyi, D.

    1994-01-01

    The physics of atomic collision phenomena in which only the Coulomb forces have a role is an actual field or the research of the present days. The impact energy range in these collisions is very broad,it extends from the eV or even lower region to the GeV region or higher,i.e. it spans the region of three branches of physics,namely that of the atomic,the nuclear and the particle physics.To describe and explain the collision processes themselves, different models (collision mechanisms) are used and they are surveyed in the presentation. Different electromagnetic radiations and particles are emitted from the collision processes.Their features are shown in details together with the most important methods in their detection and study.Examples are given based on the literature and on the investigations of the author and his coworkers. The applications of the radiation from atomic collisions in other scientific fields and in the solution of different practical problems are also surveyed shortly. 16 figs., 2 tabs., 76 refs. (author)

  13. Role of dosimetry in radiation processing applications

    International Nuclear Information System (INIS)

    Mehta, Kishor

    2001-01-01

    Today, radiation processing is a growing technology offering potential technological advantages as well as enhanced safety and economy. It is expanding on two fronts: the variety of applications is exploding as well as the sources of radiation. And with that comes the necessary advances in dosimetry. However, the success of the technology still depends on the assertion that the irradiated products are reliable and safe, whether they are health care products or cables and wires. And this is best assured through quality assurance programmes. The key element in QA in radiation processing is a well-characterised, reliable dosimetry that is traceable to the international measurement system. Traceability is the foundation for international acceptance of the irradiated products; and with international trade of irradiated products on the rise, it becomes absolutely critical. It is thus vital that the industry recognises this pivotal position of good dosimetry and the role a national standards laboratory plays in that connection. (author)

  14. Radiation entropy influx as a measure of planetary dissipative processes

    International Nuclear Information System (INIS)

    Izakov, M.N.

    1989-01-01

    Dissipative processes including high flows of matter and energy occur at the planets. Radiation negentropy influx, resulting from difference of entropy fluxes of incoming solar and outgoing thermal radiation of the planet, is a measure of all these processes. Large share of radiation negentropy influx is spent in the vertical thermal fluxes which keep the planet temperature conditions. Next share of radiation negentropy consumption at the Earth is water evaporation. It's rest part is used for the dynamics, which is explained by the efficiency insignificant amount of heat engine, which generates movements in the atmosphere and ocean. Essentially higher share of radiation negentropy influx, than at the Earth, is spent at the Venus, where there are practically no water

  15. Dosimetric aspects of radiation processing of food and allied products

    International Nuclear Information System (INIS)

    Sharma, G.; Bhat, R.M.; Bhatt, B.C.

    2010-01-01

    Full text: Gamma radiation processing in the last 4-5 decades is continuously gaining importance in processing of a wide variety of products, as it can modify physical, chemical and biological properties of the materials, including food and allied products on industrial scale due its inherent qualities like ease of processing in finally packaged form, eco-friendly nature and other obvious reasons over conventional means of processing. Food and allied products are either from agricultural produce or animal origin; they get easily contaminated from soil during harvesting, handling, processing, environment conditions, storage and transport from various types of micro-organisms including pathogens. In many countries it is mandatory to bring down the population of micro-organisms to an acceptable level and complete elimination of pathogens before such products are accepted for human or animal consumption. Processing of food and allied products by radiation has its own challenges due to wider public acceptance of irradiated food, a wide range, 0.25-50kGy, of absorbed dose requirements for different category of such products and purposes, use of a variety of packaging materials in different shapes and sizes and because of its perishable nature. More than 50 countries including India in the world have accepted radiation processing of food and allied products by radiation. Dosimetry is an important aspect of radiation processing, whether it is food or allied product. Uniformity in dose delivered to these products depends on several factors such as product carrier to source frame alignment, product carrier and product/tote box design, product loading pattern, attenuation due to product thickness, product bulk density that varies from 0.1-1.0 kg/l and the plant design whether during processing product overlaps the source or otherwise. In this presentation dosimetric aspects of radiation processing of food and allied products and problems associated with dosimetry of such

  16. Radiation processing. Current status and future possibilities

    International Nuclear Information System (INIS)

    Woods, R.J.

    2000-01-01

    Radiation processing developed following the Second World War and employees gamma- or electron-irradiation to process polymers, cure alkene-based inks and coatings, sterilize medical supplies, irradiate food, and manage wastes. The current status of these applications is described with the probable direction of future developments. (author)

  17. Research and development on radiation processing in Sri Lanka

    International Nuclear Information System (INIS)

    Kulatunge, S.S.; Motha, L.; Sultanbawa, Y.; Malavipathirana, S.; Silva, A de; Nanayakkara, S.; Hewajulige, I.G.N.; Silva, K.R.C de

    2008-01-01

    Research on radiation processing of natural polymer such as polysaccharides of chitosan, cellulose, carrageenan has been carried out in Sri Lanka since the year 2004. The research group have been involving in development activities on application of chitin and chitosan for wound dressing, irradiated chitosan on shelf life extension of fruits such as papaya, banana, mangoes, radiation crosslinked super-absorbent hydrogel from sodium carboxymethyl cellulose by radiation processing. Hydrogels prepared with PVA/Carrageenan/Agar has been studied on guinea pigs to determine the wound healing effect. Irradiated chitosan powder and chitosan solution was studied in vitro and found chitosan solution (1%) directly subjected to irradiation dosages even at 5 kGy was highly effective in control of anthracnose causing organism of papaya. In vivo studies with irradiated 1% chitosan solution on Rathana and red lady variety of papaya shows better control of spoilage of papaya to a considerable extent. The government of Sri Lanka (Ministry of Science and Technology and Atomic Energy Authority) is in the process of establishing the first government owned Multipurpose Gamma Irradiation Facility and it will be helpful to transfer the output of R and D in radiation processing. (author)

  18. Application of controlled radiation-induced degradation in polymers: less exploited aspect of radiation processing of polymers

    International Nuclear Information System (INIS)

    Haji Saeid, M.; Guven, O.

    2007-01-01

    Industrial use of ionizing radiation treatment has been most successful in applications related to polymeric materials. The polymer, plastics and rubber industries have benefited from the unique advantages of ionizing radiation since its inception as an industrial tool to modify their properties and manufacture novel materials with value addition to the end product. The established and emerging applications of electron beam processing of polymers are based on the well known ultimate effects of ionizing radiation on polymers namely, crosslinking, curing, grafting and chain scissioning. Radiation-induced crosslinking dominates most applications, whereas the chain scissioning effect is much less explored and currently limited to radiation-induced degradation of Teflon, cellulose and polypropylene. The controlling of radiation-induced degradation for achieving a target average molecular weight or distribution has been evaluated for some polysaccharides, biopolymers and waste inner tubes whereas mitigation of the degradative effects of radiation has been analyzed from the point of view of using certain stabilizers, copolymers and annealing at an appropriate temperature. Several new or highly specialized techniques such as positron annihilation lifetime spectroscopy. Rutherford backscattering, elastic recoil detection analysis and solid waste NMR spectroscopy and gas chromatography-mass spectroscopy have been applied to the study or radiation-induced degradation. New information has been collected on the morphological changes associated with radiation-induced degradation processes, including chain scission, oxidation and free volume alteration. The IAEA coordinated research project (CRP) on Controlling of Degradation Effects in Radiation Processing of Polymers dealt with the role and importance of using ionizing radiation in controlling properties of natural and synthetic polymers through its degradative effect. This paper provides a summary of most important results

  19. Pengaruh suhu vulkanisasi terhadap sifat tegangan putus, perpanjangan putus dan ketahanan sobek kompon sol karet

    Directory of Open Access Journals (Sweden)

    Prayitno Prayitno

    1995-12-01

    Full Text Available One of the processes steps for producing rubber sole is vulcanization process. This process is carried out by using pressed moulding methods in which rubber compound was heated and pressed in the mould of rubber sole at certain time and temperature. The aim of this research is to know the influence of the temperature used for vulcanization for the tensile strength, elongation and tearing strength properties of the rubber sole compound. Temperature vulcanization used for the research was varied at 1400C, 1500C, 1600C and 1700C. The results shows that vulcanization at 1400C, give the highest properties in tensile strength, elongation and tearing strength, those are : 113,70 kg/cm2; 326,60 % and 107,00 kg/cm2respectively. Increasing temperature vulcanization cause decreasing those physical properties.

  20. Quality control through dosimetry at a contract radiation processing facility

    International Nuclear Information System (INIS)

    Du Plessis, T.A.; Roediger, A.H.A.

    1985-01-01

    Reliable dosimetry procedures constitute a very important part of process control and quality assurance at a contract gamma radiation processing facility that caters for a large variety of different radiation applications. The choice, calibration and routine intercalibration of the dosimetry systems employed form the basis of a sound dosimetry policy in radiation processing. With the dosimetric procedures established, detailed dosimetric mapping of the irradiator upon commissioning (and whenever source modifications take place) is carried out to determine the radiation processing characteristics and peformance of the plant. Having established the irradiator parameters, routine dosimetry procedures, being part of the overall quality control measures, are employed. In addition to routine dosimetry, independent monitoring of routine dosimetry is performed on a bi-monthly basis and the results indicate a variation of better than 3%. On an annaul basis the dosimetry systems are intercalibrated through at least one primary standard dosimetry laboratory and to date a variation of better than 5% has been experienced. The company also participates in the Pilot Dose Assurance Service of the International Atomic Energy Agency, using the alanine/ESR dosimetry system. Routine calibration of the instrumentation employed is carried out on a regular basis. Detailed permanent records are compiled on all dosimetric and instrumentation calibrations, and the routine dosimetry employed at the plant. Certificates indicating the measured absorbed radiation doses are issued on request and in many cases are used for the dosimetric release of sterilized medical and pharmaceutical products. These procedures, used by Iso-Ster at its industrial gamma radiation facility, as well as the experience built up over a number of years using radiation dosimetry for process control and quality assurance are discussed. (author)

  1. Study of properties of chloroprene rubber devulcanizate by radiation in microwave

    Energy Technology Data Exchange (ETDEWEB)

    Scagliusi, Sandra R.; Araujo, Sumair G.; Landini, Liliane; Lugao, Ademar B., E-mail: scagliusi@usp.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    Among the vulcanized elastomers, the chloroprene rubber (DuPont Neoprene{sup R} - generic name) possesses a good performance, being one of the most used in the current days. However, this kind of polymer causes a serious environmental problem if it is not reprocessed or recycled. A worldwide method that has been used and that is an important tool in the rubber devulcanization is microwave irradiation at high temperature Elastomer waste may be devulcanized without depolymerization and allows a new vulcanization into a product having physical properties essentially equivalent to the original vulcanized. In this work, the chloroprene samples were irradiated in microwave generator equipment with 2,450 MHz (frequency) and 1,000 W to 3,000 W (power). The properties of samples (according to ASTM standards) were analyzed before and after irradiation. The degraded material after irradiation will be tested for re-use. (author)

  2. International cooperative effort to establish dosimetry standardization for radiation processing

    International Nuclear Information System (INIS)

    Farrar, Harry IV

    1990-01-01

    Radiation processing is a rapidly developing technology with numerous applications in food treatment, sterilization, and polymer modification. The effectiveness of the process depends, however, on the proper application of dose and its measurement. These aspects are being considered by a wide group of experts from around the world who have joined together to write a comprehensive set of standards for dosimetry for radiation processing. Originally formed in 1984 to develop standards for food processing dosimetry, the group has now expanded into a full subcommittee of the American Society for Testing and Materials (ASTM), with 97 members from 19 countries. The scope of the standards now includes dosimetry for all forms and applications of radiation processing. To date, the group has completed and published four standards, and is working on an additional seven. Three are specifically for food applications and the others are for all radiation applications, including food processing. Together, this set of standards will specify acceptable guidelines and methods for accomplishing the required irradiation treatment. This set will be available for adoption by national regulatory agencies or other standards-setting organizations for their procedures and protocols. (author)

  3. Expected and unexpected achievements and trends in radiation processing of polymers

    International Nuclear Information System (INIS)

    Czvikovszky, T.

    2002-01-01

    Complete text of publication follows. The last four decades produced exponential development in the polymer processing. Radiation processing yielded a similar pathway of development in the beginning, mostly in the radiation crosslinking of polymers and in the radiation sterilization of polymer products. Some expectations on several related fields such as radiation grafting, surface coating of polymer films, etc., have not really been fulfilled. There are some unexpected results in the developments of the radiation chemistry of polymers utilized well in the polymer processing today. The most dynamical developments of the microelectronics in our days is based on the efficient utilization of radiation-crosslinkable negative photoresist polymers and the radiation degradable positive photoresist polymers. Rapid prototyping and rapid tooling are indispensable methods in the continuously renewing manufacturing technologies of metal and plastic parts for almost all the industrial branches. Rapid prototyping allows to make a real polymeric part of an automobile or of a mobile phone directly from the computer assisted design draft on the monitor, without any human interference. The selective laser lithography is using radiation-reactive oligomers for this purpose. Polymer composite manufacturing is also profited in many ways from the experiences of radiation technology. High-tech composites of advanced fibers such as graphite, Kevlar, HOPE and other ones require well-engineered interface between reinforcing fiber and matrix. This interface is the key factor, especially in the case of injection-moldable composites of short fibers and thermoplastics, and this interface can greatly be improved through ionizing radiation. Our recent results in this field confirmed substantial benefits in the case of carbon fiber reinforced structures and in the case of natural fiber reinforced composites as well. Compatibilization through radiation-reactive monomers and oligomers is attacking

  4. Status and prospect of radiation processing technology in Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Khairul Zaman Hj. Mohd Dahlan; Nahrul Khair Alang Md Rashid [Malaysian Institute for Nuclear Technology Research (MINT), Bangi, Selangor Darul Ehsan (Malaysia)

    2001-03-01

    Radiation processing technology in Malaysia is gaining acceptance by the local industry. The technology has proven to enhance the industrial efficiency, productivity and improve product quality and competitiveness. For many years, variety of radiation crosslinkable materials based on synthetic polymers have been produced either in the form of thermoplastic resins, polymer blends or composites. Today, effort is being focused towards producing environmentally friendly and biodegradable materials using natural polymers. The government of Malaysia through the Malaysian Institute for Nuclear Technology Research (MINT) has developed research program to utilize indigenous materials such as natural rubber, palm oil and polysaccharide. Radiation processing technology is used to process (crosslink/grafting/curing) the materials at a competitive cost. This technology can be applied in several industrial sectors such as automobile, aerospace, construction and healthcare. (author)

  5. Status and prospect of radiation processing technology in Malaysia

    International Nuclear Information System (INIS)

    Khairul Zaman Hj Mohd Dahlan; Nahrul Khair Alang Md Rashid

    2001-01-01

    Radiation processing technology in Malaysia is gaining acceptance by the local industry. The technology has proven to enhance the industrial efficiency, productivity and improve product quality and competitiveness. For many years, variety of radiation crosslinkable materials based on synthetic polymers have been produced either in the form of thermoplastic resins, polymer blends or composites. Today, effort is being focused towards producing environmentally friendly and biodegradable materials using natural polymers. The government of Malaysia through the Malaysian Institute for Nuclear Technology Research (MINT) has developed research program to utilize indigenous materials such as natural rubber, palm oil and polysaccharide. Radiation processing technology is used to process (crosslink/grafting/curing) the materials at a competitive cost. This technology can be applied in several industrial sectors such as automobile, aerospace, construction and healthcare. (author)

  6. Dosimetry and control of radiation processing

    International Nuclear Information System (INIS)

    1988-01-01

    Eight invited papers on the general theme of 'Dosimetry and Control of Radiation Processing', presented at a one day symposium held at the National Physical Laboratory, are collected together in this document. Seven of the papers are selected and indexed separately. (author)

  7. Effects of gamma radiation in cauliflower (Brassica spp) minimally processed

    International Nuclear Information System (INIS)

    Nunes, Thaise C.F.; Rogovschi, Vladimir D.; Thomaz, Fernanda S.; Trindade, Reginaldo A.; Villavicencio, Anna L.C.H.; Alencar, Severino M.

    2007-01-01

    Consumers demand for health interests and the latest diet trends. The consumption of vegetables worldwide has increased every year over the past decade, consequently, less extreme treatments or additives are being required. Minimally processed foods have fresh-like characteristics and satisfy the new consumer demand. Food irradiation is an exposure process of the product to controlled sources of gamma radiation with the intention to destroy pathogens and to extend the shelf life. Minimally processed cauliflower (Brassica oleraceae) exposed to low dose of gamma radiation does not show any change in sensory attributes. The aim of this study was to analyze the effects of the low doses of gamma radiation on sensorial aspects like appearance, texture and flavor of minimally processed cauliflower. (author)

  8. Statistical data processing with automatic system for environmental radiation monitoring

    International Nuclear Information System (INIS)

    Zarkh, V.G.; Ostroglyadov, S.V.

    1986-01-01

    Practice of statistical data processing for radiation monitoring is exemplified, and some results obtained are presented. Experience in practical application of mathematical statistics methods for radiation monitoring data processing allowed to develop a concrete algorithm of statistical processing realized in M-6000 minicomputer. The suggested algorithm by its content is divided into 3 parts: parametrical data processing and hypotheses test, pair and multiple correlation analysis. Statistical processing programms are in a dialogue operation. The above algorithm was used to process observed data over radioactive waste disposal control region. Results of surface waters monitoring processing are presented

  9. Occupational radiation protection in the mining and processing of raw materials

    International Nuclear Information System (INIS)

    2004-01-01

    The mining and processing of uranium ore, thorium ore and other raw materials containing natural radionuclides are carried out in a number of Member States. There is a clear need to update the guidance on the radiation protection of the workers involved, and this Safety Guide provides such updated guidance. Material from two previous publications has been adapted for inclusion in this Safety Guide. These previous publications - Radiation Monitoring in the Mining and Milling of Radioactive Ores (Safety Series No. 95) and Radiation Protection of Workers in the Mining and Milling of Radioactive Ores (Safety Series No. 26, hereby superseded) - dealt principally with activities involving uranium ore and thorium ore. Activity concentrations of naturally occurring radionuclides are elevated in other mineral deposits such as heavy mineral sands and phosphate rock. Furthermore, high radon levels may be found in mines, irrespective of the activity concentrations of natural radionuclides in the raw material being extracted. In recognition of these circumstances, this Safety Guide is intended to apply also to the mining and processing of any raw material for which radiation protection measures need to be considered. The IAEA Safety Fundamentals publication on Radiation Protection and the Safety of Radiation Sources presents the principles, concepts and objectives of protection and safety. Safety requirements based on the objectives and principles specified in these Safety Fundamentals, including requirements for the protection of workers exposed to ionizing radiation, are established in the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (the Basic Safety Standards or Bss). These requirements also reflect the recommendations of the International Commission on Radiological Protection (ICRP). Safety Guides provide recommendations on the basis of international experience on the fulfilment of the requirements

  10. O efeito de EPDM modificado com grupos mercapto ou tioacetato na cinética de vulcanização de misturas NR/EPDM The effect of mercapto- and thioacetate-modified EPDM on the vulcanization kinetics of NR/EPDM blends

    Directory of Open Access Journals (Sweden)

    Alex S. Sirqueira

    2006-12-01

    Full Text Available A cinética de vulcanização de misturas envolvendo borracha natural (NR e copolímero de etileno-propileno-dieno (EPDM na proporção 70:30 % em peso foi estudada em função da compatibilização. Para esse estudo foram utilizados 2,5 phr de EPDM funcionalizado com grupos tioacetato (EPDMTA ou mercaptana (EPDMSH. O estudo foi realizado em reômetro de disco oscilatório (curômetro. Ambos os copolímeros funcionalizados atuaram como aceleradores do processo de vulcanização das misturas NR/EPDM (70:30 na presença de enxofre e CBS, sendo EPDMSH mais efetivo do que EPDMTA pelo modelo de Chough e Chang. Entretanto, ao utilizar o modelo de Coran, observou-se que EPDMTA e EP-DMSH atuam em distintas etapas da vulcanização: EPDMSH atua preferencialmente no início do processo de vulcanização enquanto que EPDMTA aumenta a velocidade da formação das reticulações propriamente ditas. Além disso, EPDMTA diminuiu consideravelmente a tendência à degradação de reticulações, indicada pela menor taxa de reversão.Vulcanization kinetics for natural rubber (NR/ ethylene-propylene-diene rubber (EPDM blends was studied as a function of the compatibilization, by using an oscillatory disk rheometer. For this study, 2.5 phr of thioacetate- (EPDMTA or mercapto-modified EPDM (EPDMSH were employed in blends vulcanized with sulfur/CBS curing system. Both functionalized copolymers increased the curing velocity of the blends, but the higher overall rate was achieved with EPDMSH-modified systems, using the Chough and Chang model. However, when using the Coran model, we observed that they act in distinct vulcanization steps: EPDMSH acts preferentially at the beginning of the curing process whereas EPDMTA increases the rate of the crosslink formation. In addition, EPDMTA decreased the tendency for crosslink decomposition, as indicated by the lower value of reversion degree.

  11. Recent developments in analytical detection methods for radiation processed foods

    International Nuclear Information System (INIS)

    Wu Jilan

    1993-01-01

    A short summary of the programmes of 'ADMIT' (FAO/IAEA) and the developments in analytical detection methods for radiation processed foods has been given. It is suggested that for promoting the commercialization of radiation processed foods and controlling its quality, one must pay more attention to the study of analytical detection methods of irradiated food

  12. Comparison between the mechanical and radiative electron-capture processes at high energies

    International Nuclear Information System (INIS)

    Gonzalez, A.D.; Miraglia, J.E.

    1984-01-01

    The ground-state--ground-state mechanical and radiative electron-capture processes are studied at very high, but not relativistic, projectile velocities. Three-body calculations were carried out with use of the continuum distorted-wave theoretical method for both processes. Total cross sections and final-atom angular distributions were computed, and the importance of each mechanism examined. For total cross sections, the numerical results reaffirm that the radiative process is the predominant mechanism at very high projectile energies. For a given incident charge, the range of projectile energies in which the nonrelativistic radiative mechanism is the most important decreases as the target charge increases. It is found that the radiative mechanism produces a very sharp final-atom angular distribution in the forward direction. When both processes, the radiative and mechanical, give the same total cross section, the calculations show that the radiative differential cross section in the forward direction is almost 2 orders of magnitude larger than the mechanical one

  13. Radiation influence on heterogenous processes in stainless steel contact with sea-water

    International Nuclear Information System (INIS)

    Agayev, T.N.; Garibov, A.A.; Velibekova, G.Z.; Aliyev, A.Q.; Aliyev, S.M.

    2005-01-01

    Full text: Austenitic stainless steel (s.s.) with Cr content 16 %, Ni - 15 % is widely used in nuclear reactors as construction material, for fuel cladding production and also is used in oil and gas production and transportation. They possess comparatively large section of slow neutron capture and as a result high corrosion resistance. In real exploitation condition of nuclear reactors s.s. are exposed to ionizing radiation influence in contact of different media. That's why during their corrosion and destruction processes the surface defect formation processes and further heterogenous processes with their participation are of great importance. The research results of mechanism during radiation-heterogenous processes in nuclear reactor stainless steel contact with sea-water under the influence of γ-radiation in temperature interval 300-1074 K are represented in the given work. Radiolytic processes in water are comprehensively studied and therefore it was taken as model system for dating the surface defects and secondary electrons emitted from metal. The same model system was applied also in sea-water radiolysis processes. It's been established that radiation processes in s.s. lead to molecular hydrogen yield increase and at T=300 K up to 6.5 molec./100 eV. With the temperature increase molecular hydrogen yield increase up to 25.3 molec./100 eV at T≤773 K. During the further temperature increase up to 1073 K radiation constituent of radiation-thermal process in comparison with thermal becomes unnoticeable and W T (H 2 )≅W p (H 2 ). The kinetics of oxide phase formation of investigated sample surface in the result of thermal and radiation-thermal processes in their contact with sea-water has been studied. At that it's been shown that radiation leads to protective oxidation process rate increase and promotes the beginning of stainless steel destruction oxidation in contact with sea-water. At T≥573 K insoluble oxide phase is formed on metal surface that promotes

  14. In situ reactive compatibilization of natural rubber/acrylic-bentonite composites via peroxide-induced vulcanization

    International Nuclear Information System (INIS)

    Fu, Lihua; Lei, Zhiwen; Xu, Chuanhui; Chen, Yukun

    2016-01-01

    To achieve good interfacial interaction between fillers and rubber matrix is always a hot topic in rubber reinforcing industry. In this paper, acid activated bentonite (Bt) was alkalified to be alkaline calcium-bentonite (ACBt), then acrylic acid (AA) was employed to modify ACBt to obtain acrylic-bentonite (ABt). The results of Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) illustrated that acrylate groups were chemically boned onto the surface of Bt and the layer spacing of Bt was increased. During peroxide-induced vulcanization, in situ compatibilization of ABt was realized via the reaction between the unsaturated bonds of acrylate groups on the surface of Bt and the natural rubber (NR) chains. This resulted in an enhanced cross-linked network which contributed to the improved mechanical properties of NR/ABt composites. - Highlights: • Acrylate groups were chemically boned onto the surface of bentonite. • In situ compatibilization was realized via the reaction of acrylate group and NR. • ABt particles participated in forming the NR crosslink network. • A potential reinforcing material options for “white” rubber products.

  15. In situ reactive compatibilization of natural rubber/acrylic-bentonite composites via peroxide-induced vulcanization

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Lihua; Lei, Zhiwen [Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Xu, Chuanhui, E-mail: xuhuiyee@gxu.edu.cn [Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Chen, Yukun, E-mail: cyk@scut.edu.cn [The Key Laboratory of Polymer Processing Engineering, Ministry of Education, China(South China University of Technology), Guangzhou, 510640 (China)

    2016-02-15

    To achieve good interfacial interaction between fillers and rubber matrix is always a hot topic in rubber reinforcing industry. In this paper, acid activated bentonite (Bt) was alkalified to be alkaline calcium-bentonite (ACBt), then acrylic acid (AA) was employed to modify ACBt to obtain acrylic-bentonite (ABt). The results of Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) illustrated that acrylate groups were chemically boned onto the surface of Bt and the layer spacing of Bt was increased. During peroxide-induced vulcanization, in situ compatibilization of ABt was realized via the reaction between the unsaturated bonds of acrylate groups on the surface of Bt and the natural rubber (NR) chains. This resulted in an enhanced cross-linked network which contributed to the improved mechanical properties of NR/ABt composites. - Highlights: • Acrylate groups were chemically boned onto the surface of bentonite. • In situ compatibilization was realized via the reaction of acrylate group and NR. • ABt particles participated in forming the NR crosslink network. • A potential reinforcing material options for “white” rubber products.

  16. Radiation processing technology in the 21st century

    International Nuclear Information System (INIS)

    Miyuki Hagiwara

    1997-01-01

    The address discusses the following issue - towards the 21st century, we are required more and more to create innovative technologies to solve problems about environment, energy, natural resources, materials, health care, food and others which are the great concern to human beings. For the radiation processing technology to survive, it will be required to provide answers to those problems. The use of radiation of polymer modification will remain as an important field of the radiation application. Some other promising polymer processing can be cited as those which will grow in near future; for environment technology - polymeric fibers grafted with ion exchange residues to remove toxic metals for cleaning industrial waste water; For health care technology - crosslinked polyvinylalcohol hydrogel for wound dressing (irradiation of hydrogel); For high performance materials technology - less toxic crosslinked natural rubber latex (irradiation of emulsion), abrasion resistant crosslinked PTFE (irradiation at high temperature)

  17. Development of new radiation resistant, fire-retardant cables. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hagiwara, Ko; Morita, Yosuke; Udagawa, Takashi (Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment); Fujimura, Shun-ichi; Oda, Eisuke

    1982-12-01

    For the cables for nuclear facilities, radiation resistance and fire-retardation are severely required. The authors took note of the fact that even in the existing cables for nuclear power plants, their mechanical properties are greatly degraded by the exposure to large dose (for example, 200 Mrad in PWR testing conditions), and attempted the improvement. They employed a new additive, bromated acenaphthylene condensate (con-BACN), which effectively gives radiation resistance and also is a good flame retarder, to be compounded to an insulation material, and examined the characteristics. In this paper, the features of con-BACN and the investigation of fire-retardant EPDM composition are described. As an initial composition, a small amount of zinc white, sulphur, stearic acid, noclac 224 (Ouchi-Shinko Chemicals, Co.), and antimony trioxide, 100 parts of tale and 45 parts of con-BACN were added to 100 parts of EPDM (propylene content 34 %, Japan Synthetic Rubber Co.). As the antiaging agent, it was decided to use phenol series No. 3 as a result of test. The fire-retardant EP rubber-composed cable was produced for trial, its insulation being fabricated, using a Furukawa's pressurized salt bath continuous vulcanizer. The tests of ..gamma..-irradiation, simulated LOCA and combustion were carried out, and the test results are reported. It was indicated that the cable resisted against high dose several times as much as 200 Mrad, and was suitable for the applications, in which the mechanical properties such as bending are required to be maintained after radiation exposure. It was also found that con-BACN was safe, and its properties of decomposition, concentration and acute toxicity were all very low.

  18. Radiation processing of polymers with high energy electron beams: novel materials and processes

    International Nuclear Information System (INIS)

    Sarma, K.S.S.; Sabharwal, Sunil

    2002-01-01

    High-energy ionizing radiation available from electron beam (EB) accelerators has the ability to create extremely reactive species like free radicals or ions at room temperature or even at low temperature in any phase and in a variety of substrates without addition of external additives. This unique advantage of high energy has been utilized in the recent years to produce better quality materials in an environment friendly and cost-effective manner. The availability of high power and reliable EB accelerators has provided new tools to modify the materials and/or processes for a variety of applications. At BARC, a 2 MeV, 20 kW electron beam accelerator has been the nucleus of developing industrial applications of radiation processing in India for last 10 years. The focus has been on developing technologies that are of relevance to Indian socio-economic conditions and also provide economic benefits to the industry. In the areas of polymer processing industry, commercial success has already been achieved while for exploring its applications in the areas of food and agriculture and environment, technology demonstration plants are being set up. The current status of the programme, the new developments and future direction of radiation processing technology shall be presented in this paper. (author)

  19. Current status of the radiation technology and quality control for radiation processing in Latin America

    International Nuclear Information System (INIS)

    Miranda, Enrique Francisco Prietro

    2013-01-01

    The use of the radiation technology has gained acceptance in various regions of the world, where studies estimated that the installed capacity increases at a rate of 6 % per year and Latin America is part of this increase, due the advantages of this process when it is employed for the food preservation, sterilization of medical pharmaceutical material and to control the insect pests. This paper shows the art state of the application of Radiation Technology in Latin America, as well as the technological characteristics of the most gamma irradiation facilities and minor number the electron beam accelerator facilities, the types of irradiated products, state of the Quality Management System and the Dosimetric Systems used in the Radiation Processing Control in the Region. (author)

  20. Radiation processes for the control of NOx/SO2 emissions

    International Nuclear Information System (INIS)

    Dickson, L.W.; Singh, A.

    1988-01-01

    This report provides a brief review of the use of radiation for the treatment of flue gases and identifies areas for additional research. Two different radiation-based processes have been developed for the removal of nitrogen oxides and sulphur dioxide from the flue gases of coal-fired boilers. In the technique developed by the Ebara Corporation and Japan Atomic Energy Research Institute, ammonia is injected prior to the irradiation step to enhance the process efficiency and to yield a solid ammonium sulphate - ammonium nitrate product that may be used as a fertilizer. The process developed by the Research-Cottrell Corporation uses electron-beam irradiation downstream of a lime spray dryer to remove nitrogen oxides and to enhance the sulphur dioxide removal efficiency. Both of these processes require large quantities of electron-beam power and are currently expected to be more expensive than other available sulphur dioxide emission control technologies. Present emission control regulations in North America do not require the high degree of nitrogen oxide removal provided by the radiation-based processes. Research into the radiolytic oxidation of nitrogen oxides and sulphur dioxide, the radiolytic oxidation of NO x /SO 2 on solid sorbents, and the radiolytic oxidation of NO x /SO 2 in electric fields may lead to the development of more economical radiation treatment processes for flue gases. 44 refs

  1. Emerging applications of radiation processing. Proceedings of a technical meeting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-01-01

    Approximately 160 gamma irradiators and 1200 electron accelerator based processing units are in operation worldwide. In recent years the IAEA has prepared a directory of industrial gamma irradiators and held several meetings on developments in radiation technology applications. Developments involving the engineering of new sources (both isotope and electrical), high power accelerator applications, etc. have been reported recently, making a review and evaluation of this progress timely. Therefore the IAEA organized a technical meeting in Vienna, Austria, from 28 to 30 April 2003 to review the present situation and the potential contribution of radiation technology to sustainable development. Engineering developments and other features of radiation sources, both isotope and accelerator, were discussed. Recent research has concentrated on three fields: medical and food products, polymers, and environmental pollution control. The stability of radiation sterilized medical implants, as well as the uses of radiation processing for sterilization or decontamination of pharmaceuticals and pharmaceutical raw materials, radiation synthesis and modification of polymers for biomedical applications have been studied. Since separation and enrichment technologies play an important role in product recovery and pollution control, the possibility of radiation synthesis of stimuli-responsive membranes, hydrogels and adsorbents is being investigated. Finally, aside from the technologies for flue gas and wastewater treatment already in use, further research is ongoing on the treatment of organic contaminants in both gaseous and liquid phases. Environmental applications, which also offer new opportunities, should be carefully reviewed to reflect existing regulations and current knowledge. The increasingly serious problem of polyaromatic hydrocarbons (PAH) emissions may be solved in part by the application of radiation technology. This is being studied on a pilot scale for the removal of

  2. Emerging applications of radiation processing. Proceedings of a technical meeting

    International Nuclear Information System (INIS)

    2004-01-01

    Approximately 160 gamma irradiators and 1200 electron accelerator based processing units are in operation worldwide. In recent years the IAEA has prepared a directory of industrial gamma irradiators and held several meetings on developments in radiation technology applications. Developments involving the engineering of new sources (both isotope and electrical), high power accelerator applications, etc. have been reported recently, making a review and evaluation of this progress timely. Therefore the IAEA organized a technical meeting in Vienna, Austria, from 28 to 30 April 2003 to review the present situation and the potential contribution of radiation technology to sustainable development. Engineering developments and other features of radiation sources, both isotope and accelerator, were discussed. Recent research has concentrated on three fields: medical and food products, polymers, and environmental pollution control. The stability of radiation sterilized medical implants, as well as the uses of radiation processing for sterilization or decontamination of pharmaceuticals and pharmaceutical raw materials, radiation synthesis and modification of polymers for biomedical applications have been studied. Since separation and enrichment technologies play an important role in product recovery and pollution control, the possibility of radiation synthesis of stimuli-responsive membranes, hydrogels and adsorbents is being investigated. Finally, aside from the technologies for flue gas and wastewater treatment already in use, further research is ongoing on the treatment of organic contaminants in both gaseous and liquid phases. Environmental applications, which also offer new opportunities, should be carefully reviewed to reflect existing regulations and current knowledge. The increasingly serious problem of polyaromatic hydrocarbons (PAH) emissions may be solved in part by the application of radiation technology. This is being studied on a pilot scale for the removal of

  3. Pilot material handling system for radiation processing of agricultural and medical products

    International Nuclear Information System (INIS)

    Sandha, R.S.; Nageswar Rao, J; Dwivedi, Jishnu; Petwal, V.C.; Soni, H.C.

    2005-01-01

    A 10 MeV, 10 kW electron LINAC based radiation processing facility is being constructed at Centre for Advanced Technology, Indore for radiation processing of various food products like potatoes, onion, spices, home pack items and medical sterilization. A pilot material handling system has been designed, manufactured, and installed at CAT to verify process parameters viz. conveying speed, dose uniformity, and to study the effect of packing shape and size for radiation processing of different product. This paper describes various features of pilot material handling system. (author)

  4. Use of radiation processing technology gradually expands in industry

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    The use of radioisotopes and radiation is expanding in the fields of industries and medicine with a high potentiality of the application to environmental protection. The technology transfer on the use of isotopes and radiation is progressing in the framework of international cooperation. But the industry has maintained wait and see attitude on the commercialization of food irradiation. Such present features were the highlight in the 19th Japan Conference on Radiation and Radioisotopes held on November 14-16. 72 papers from 19 countries were presented and discussed in 13 sessions. The progress of accelerator technology has contributed to the expansion of radiation processing market. The importance of the application of isotopes and radiation to environmental protection has been gradually acknowledged, and the electron beam treatment of flue gas for acid rain abatement and the elimination of chlorinated ethylene from drinking water were discussed. Drastic change has not been seen in the climate of food irradiation, however there are several positive indicators which support the prediction of slow but steady progress in the commercialization of the process and the trade of irradiated foods. (K.I.)

  5. Global trends in radiation processing

    International Nuclear Information System (INIS)

    Defalco, G.

    2003-01-01

    There will be a brief introduction of the companies of MDS serving the Medical, Biotechnology and Pharmaceutical sectors worldwide. MDS Nordion will be introduced in more detail focused on the products and services of our Nuclear Medicine and Ion Technologies business units. World Trends and issues in Radiation Processing will be discussed on: Sterilization of Medical Devices, Pharmaceuticals, Cosmetics and Consumer products and finally I will present an overview on Food Irradiation progress worldwide

  6. Radiation-induced processes in the metallic powders after electron and gamma-radiation

    International Nuclear Information System (INIS)

    Zajkin, Yu.A.; Aliev, B.A.

    2001-01-01

    In the work the quantitative assessments for conditions both healing and growth of micropores in metal volume and surface layers have been made. Taking into account of these rules is important at a choice of radiation processing conditions for fine-disperse powders characterizing with increased porosity. Numerical evaluation shows, that under irradiation of a metals by electrons with energy 2 MeV and electron current density about 1 μA/cm 2 within 300-400 K temperature range the optimal doses for the micropores healing make up a several Mrad. Further increase of dose could lead to formation of pores in the crystal volume. Principal conclusions about radiation porosity development character of metallic particles surface layers one can make from analysis of the point defects distribution near surface and computing of radiation-induced diffusion coefficients

  7. Developments and potential of radiation processing in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Singson, C; Carmona, C [Philippine Atomic Energy Commission, Diliman, Quezon City

    1981-01-01

    This paper describes the research and development activities in three areas of radiation processing, namely: food irradiation, medical product sterilization and wood plastic combination. Plans and efforts exerted to acquire a larger gamma source to augment our present 5,000 curie source are discussed. Cost estimates for a radiation facility are presented on the basis of the market potential of food irradiation and medical product sterilization. Existing local industries that can benefit from the adaptation of irradiation technology in their processing requirements are described.

  8. Radiation biology using synchrotron radiation. In relation to radiation chemistry as an initial process

    International Nuclear Information System (INIS)

    Kobayashi, Katsumi

    1995-01-01

    Radiation biology using synchrotron radiation have been investigated, focusing on the mechanism of the formation of molecular damage. This paper introduces recent outcome of these studies. First, the process from imparted energy to the formation of molecular damage is outlined. The previous studies can be largely categorized as dealing with (1) biological effects of inner-shell ionization on elements composing the living body and (2) X-ray energy dependence of biological effects. Bromine and phosphorus are used as elements for the study of inner-cell ionization. In the study on lethal effects of monochromatic soft X-rays on the BrdUMP-incorporated yeast cells, Auger enhancement was found to occur. The first report on the effects of K-shell absorption of cellular phosphorus atoms has revealed that biological effects on cellular lethality and genetic changes was enhanced by 40%. Plasmid DNA and oligonucleotide have been used to study biological effects of vacuum ultraviolet rays to monochromatic soft X-ray, which makes it possible to study strand breaks. Because experimental production of energy required for the formation of double strand breaks has become possible, synchrotron radiation plays a very important role in radiation biological studies. Finally, future issues are presented. (N.K.)

  9. Electro-oxidation of methanol in alkaline conditions using Pd–Ni nanoparticles prepared from organometallic precursors and supported on carbon vulcan

    Energy Technology Data Exchange (ETDEWEB)

    Manzo-Robledo, A., E-mail: amanzor@ipn.mx [UPALM, Laboratorio de Electroquímica y Corrosión, Escuela Superior de Ingeniería Química e Industrias Extractivas-IPN (Mexico); Costa, Natália J. S. [Universidade de São Paulo, Instituto de Química (Brazil); Philippot, K. [CNRS, LCC, Laboratoire de Chimie de Coordination (France); Rossi, Liane M. [Universidade de São Paulo, Instituto de Química (Brazil); Ramírez-Meneses, E. [Universidad Iberoamericana, Departamento de Ingeniería y Ciencias Químicas (Mexico); Guerrero-Ortega, L. P. A. [UPALM, Laboratorio de Electroquímica y Corrosión, Escuela Superior de Ingeniería Química e Industrias Extractivas-IPN (Mexico); Ezquerra-Quiroga, S. [Universidad Iberoamericana, Departamento de Ingeniería y Ciencias Químicas (Mexico)

    2015-12-15

    Oxidation of low-molecular weight alcohols as energy sources using metal nanoparticles has attracted considerable interest for use as a power source in portable electronic devices. In this work, a series of mono- and bimetallic nanoparticles based on palladium and nickel (Pd, Pd{sub 90}Ni{sub 10}, Pd{sub 50}Ni{sub 50}, Pd{sub 10}Ni{sub 90}, and Ni) have been synthesized from organometallic precursors, namely tris(dibenzylideneacetone) dipalladium(0), Pd{sub 2}(dba){sub 3}, and bis(1,5-cyclooctadiene)nickel(0), Ni(cod){sub 2}. Well-defined metal particles in the nanometric scale from 4.2 to 6.3 nm were observed by transmission electron microscopy. The as-prepared nanoparticles were mixed with a carbon Vulcan matrix (10 % wt. of the catalyst in turn) for investigation as electrocatalysts in methanol oxidation reaction (MOR) in alkaline conditions. The i–E profiles from cyclic voltammetry for the monometallic systems indicated a redox process attributed only to palladium or nickel, as expected. With the bimetallic nanomaterials, the redox process and the i–E characteristics are functions of the amount of nickel associated to palladium. From a fundamental point of view, it has been established that the OH ions’ interfacial interaction and the MOR kinetics are affected by the presence of nickel (decreasing the faradic current) as supported by the current versus potential profiles obtained as a function of methanol concentration and with temperature variation.

  10. Radiation methods in dairy production and processing

    International Nuclear Information System (INIS)

    Ganguli, N.C.

    1975-01-01

    Various uses of radiotracers and radiation in dairy technology are described. In dairy production, radiotracers are used for studying: (1) rumen metabolism leading to protein synthesis (2) total body water, blood volume and sodium (3) minerals metabolism (4) relation between climatic stress and thyroid functioning of dairy animals (5) volume of milk in mammary glands (6) hormone level in dairy animals and (7) spermatozoa metabolism. In dairy processing, radiotracers are used for studying: (1) compositional analysis of milk and milk products and (2) efficiency of cleaning agents for cleaning dairy equipment. Ionizing radiation is used for: (1) preservation of milk and milk products and (2) sterilization of packaging materials. Radiation source has been used to monitor the over-run in ice-cream and the fill control for fluid in papar cartons. (M.G.B.)

  11. Quality audit service of the IAEA for radiation processing dosimetry

    International Nuclear Information System (INIS)

    Mehta, K.; Girzikowsky, R.

    1996-01-01

    The mandate of the International Atomic Energy Agency includes assistance to Member States to establish nuclear technologies safely and effectively. In pursuit of this, a quality audit service for dosimetry relevant to radiation processing was initiated as a key element of the High-Dose Standardization Programme of the IAEA. The standardization of dosimetry for radiation processing provides a justification for the regulatory approval of irradiated products and their unrestricted international trade. In recent times, the Agency's Dosimetry Laboratory has placed concentrated effort towards establishing a quality assurance programme based on the ISO 9000 series documents. The need for reliable and accurate dosimetry for radiation processing is increasing in Member States and we can envisage a definite role for the SSDLs in such a programme. (author). 10 refs, 3 figs

  12. One Hair Postulate for Hawking Radiation as Tunneling Process

    International Nuclear Information System (INIS)

    Dong Hui; Sun Chang-Pu; Cai Qing-Yu; Liu Xu-Feng

    2014-01-01

    For Hawking radiation, treated as a tunneling process, the no-hair theorem of black hole together with the law of energy conservation is utilized to postulate that the tunneling rate only depends on the external qualities (e.g., the mass for the Schwarzschild black hole) and the energy of the radiated particle. This postulate is justified by the WKB approximation for calculating the tunneling probability. Based on this postulate, a general formula for the tunneling probability is derived without referring to the concrete form of black hole metric. This formula implies an intrinsic correlation between the successive processes of the black hole radiation of two or more particles. It also suggests a kind of entropy conservation and thus resolves the puzzle of black hole information loss in some sense. (general)

  13. Chemistry and technology of radiation processed composite materials

    International Nuclear Information System (INIS)

    Czvikovszky, T.

    1985-01-01

    Composite materials of synthetics (based on monomers, oligomers and thermoplastics) and of natural polymers (wood and other fibrous cellulosics) prepared by radiation processing, offer valuable structural materials with enhanced coupling forces between the components. The applied polymer chemistry of such composites shows several common features with that of radiation grafting, e.g. the polymerization rate of oligomer-monomer mixtures in wood remains in most cases proportional to the square-root of the initiating dose-rate, just as in the simultaneous grafting, demonstrating that the chain termination kinetics remain regularly bimolecular in the corresponding dose-rate ranges. In the processing experiences of such composites, low dose requirement, easy process-control, and good technical feasibility have been found for composites of wood with oligomer-monomer mixtures, for coconut fibres with unsaturated polyesters and for pretreated wood fibre with polypropylene. (author)

  14. Cobalt 60 availability for radiation processing

    International Nuclear Information System (INIS)

    Fraser, F.M.

    1986-01-01

    In the last 20 years, the steady and significant growth in the application of radiation processing to industrial sterilization has been seen. The principal application of this technology is the sterilization of disposable medical products, food irradiation, the irradiation of personal care goods and so on. At present, more than 70 million curies of cobalt-60 supplied by Atomic Energy of Canada Ltd. have been used for gamma processing in these applications. This is estimated to be more than 80 % of the total cobalt-60 in service in the world. Commercial food irradiation has an exciting future, and as to the impact of food irradiation on the availability of cobalt-60 over the next ten years, two principal factors must be examined, namely, the anticipated demand for cobalt-60 in all radiation processing applications, and the supply of cobalt-60 to reliably meet the expected demand. As for the cobalt-60 in service today, 90 % is used for the sterilization of disposable medical products, 5 % for food irradiation, and 5 % for other application. The demand for up to 30 million curies of cobalt-60 is expected over the next 10 years. Today, it is estimated that over 150,000 tons of spices, fruit and fish are irradiated. The potential cobalt-60 production could exceed 110 million curies per year. Gamma processing application will demand nearly 50 million curies in 1990. (Kako, I.)

  15. Organoleptic quality and antioxidant status of radiation processed food commodities

    International Nuclear Information System (INIS)

    Chatterjee, S.; Sharma, J.; Arul, A.K.; Variyar, P.S.; Sharma, A.

    2009-01-01

    Effect of radiation processing on the organoleptic qualities such as aroma, taste and colour as well as antioxidant status of various food classes such as beverages (monsooned coffee), spices (nutmeg), fruits (pomegranate), oil seeds (soybean) and vegetables (guar beans) was investigated. The factors responsible for these attributes were shown to be liberated from their glycosidic precursors during radiation processing, thus resulted in an enhancement of organoleptic quality and antioxidant status. (author)

  16. Enhancement of efficiency of storage and processing of food raw materials using radiation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Gracheva, A. Yu.; Zav’yalov, M. A.; Ilyukhina, N. V.; Kukhto, V. A.; Tarasyuk, V. T.; Filippovich, V. P. [All-Russia Research Institute of Preservation Technology (Russian Federation); Egorkin, A. V.; Chasovskikh, A. V. [Research Institute of Technical Physics and Automation (Russian Federation); Pavlov, Yu. S., E-mail: rad05@bk.ru [Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences (Russian Federation); Prokopenko, A. V., E-mail: pav14@mail.ru [National Research Nuclear University (Moscow Engineering Physics Institute) (Russian Federation); Strokova, N. E. [Moscow State University (Russian Federation); Artem’ev, S. A. [Russian Research Institute of Baking Industry (Russian Federation); Polyakova, S. P. [Russian Research Institute of Confectionery Industry (Russian Federation)

    2016-12-15

    The work is dedicated to improvement of efficiency of storage and processing of food raw materials using radiation technologies. International practice of radiation processing of food raw materials is presented and an increase in the consumption of irradiated food products is shown. The prospects of using radiation technologies for the processing of food products in Russia are discussed. The results of studies of radiation effects on various food products and packaging film by γ radiation and accelerated electrons are presented.

  17. Enhancement of efficiency of storage and processing of food raw materials using radiation technologies

    International Nuclear Information System (INIS)

    Gracheva, A. Yu.; Zav’yalov, M. A.; Ilyukhina, N. V.; Kukhto, V. A.; Tarasyuk, V. T.; Filippovich, V. P.; Egorkin, A. V.; Chasovskikh, A. V.; Pavlov, Yu. S.; Prokopenko, A. V.; Strokova, N. E.; Artem’ev, S. A.; Polyakova, S. P.

    2016-01-01

    The work is dedicated to improvement of efficiency of storage and processing of food raw materials using radiation technologies. International practice of radiation processing of food raw materials is presented and an increase in the consumption of irradiated food products is shown. The prospects of using radiation technologies for the processing of food products in Russia are discussed. The results of studies of radiation effects on various food products and packaging film by γ radiation and accelerated electrons are presented.

  18. An assessment of prospects for radiation processing in Yugoslavia

    International Nuclear Information System (INIS)

    Razem, D.; Dvornik, I.

    1981-01-01

    The possibilities are reviewed under the headings: food irradiation; sterilization of medical supplies; crosslinking of polymers. It is concluded that radiation sterilization of disposable medical supplies appears most attractive for immediate application; food irradiation can have only a limited success, at least with the present generation of strong inherited attitudes. Processes for radiation crosslinking of polymers are to a large extent subject to industrial secrecy; however, some possibilities are seen. A center for radiation services in Yugoslavia is proposed. (U.K.)

  19. Outline of an experimental apparatus for the study on the advanced voloxidation process

    International Nuclear Information System (INIS)

    Uchiyama, Gunzo; Sugikawa, Susumu; Maeda, Mitsuru; Tsujino, Takeshi; Torikai, Seishi; Kitamura, Masafumi; Yamazaki, Kazunobu.

    1990-02-01

    The experimental apparatus (VULCAN, the capacity; 2 kg-UO 2 /batch) was constructed to study on the advanced voloxidation process, which was proposed to reduce amount of tritium released from fuel reprocessing facilities. Using this equipment, a process study was conducted on behaviors of oxidation-reduction of simulated fuels and of release of tritium, and on confinement function of rotary seal of the reactor. An outline of the experimental apparatus is described. (author)

  20. Radiation processing of biological tissues for nuclear disaster management

    International Nuclear Information System (INIS)

    Singh, Rita

    2012-01-01

    A number of surgical procedures require tissue substitutes to repair or replace damaged or diseased tissues. Biological tissues from human donor like bone, skin, amniotic membrane and other soft tissues can be used for repair or reconstruction of the injured part of the body. Tissues from human donor can be processed and banked for orthopaedic, spinal, trauma and other surgical procedures. Allograft tissues provide an excellent alternative to autografts. The use of allograft tissue avoids the donor site morbidity and reduces the operating time, expense and trauma associated with the acquisition of autografts. Further, allografts have the added advantage of being available in large quantities. This has led to a global increase in allogeneic transplantation and development of tissue banking. However, the risk of infectious disease transmission via tissue allografts is a major concern. Therefore, tissue allografts should be sterilized to make them safe for clinical use. Radiation processing has well appreciated technological advantages and is the most suitable method for sterilization of biological tissues. Radiation processed biological tissues can be provided by the tissue banks for the management of injuries due to a nuclear disaster. A nuclear detonation will result in a large number of casualties due to the heat, blast and radiation effects of the weapon. Skin dressings or skin substitutes like allograft skin, xenograft skin and amniotic membrane can be used for the treatment of thermal burns and radiation induced skin injuries. Bone grafts can be employed for repairing fracture defects, filling in destroyed regions of bone, management of open fractures and joint injuries. Radiation processed tissues have the potential to repair or reconstruct damaged tissues and can be of great assistance in the treatment of injuries due to the nuclear weapon. (author)

  1. Radiation Safety Professional Certification Process in a Multi-Disciplinary Association

    International Nuclear Information System (INIS)

    Wilson, G.; Jones, P.; Ilson, R.

    2004-01-01

    There is no one set of criteria that defines the radiation safety professional in Canada. The many varied positions, from university and medical to industry and mining, define different qualifications to manage radiation safety programs. The national regulatory body has to assess many different qualifications when determining if an individual is acceptable to be approved for the role of radiation safety officer under any given licence. Some professional organizations specify education requirements and work experience as a prerequisite to certification. The education component specifies a degree of some type but does not identify specific courses or competencies within that degree. This could result in individuals with varying levels of radiation safety experience and training. The Canadian Radiation Protection Association (CRPA), responding to a need identified by the membership of the association, has initiated a process where the varying levels of knowledge of radiation safety can be addressed for radiation safety professionals. By identifying a core level set of radiation safety competencies, the basic level of radiation safety officer for smaller organizations can be met. By adding specialty areas, education can be pursued to define the more complex needs of larger organizations. This competency based process meets the needs of licensees who do not require highly trained health physicists in order to meet the licensing requirements and at the same time provides a stepping stone for those who wish to pursue a more specialized health physics option. (Author) 8 refs

  2. Radiation processing of polyethylene and polymethylmethacrylate for construction industry and architecture

    International Nuclear Information System (INIS)

    Knizhnik, E.I.; Gordienko, V.P.; Il'yenko, R.E.; Onisko, A.D.; AN Ukrainskoj SSR, Kiev. Inst. Fizicheskoj Khimii)

    1983-01-01

    Radiation processing of relief-forming molds made of filled high-density polyethylene enables them to be used for shaping concrete and ferroconcrete barrier constructions of buildings; radiation processing of polymethylmethacrylate in unit form makes it possible to produce large-size decorative elements of building interior. The subject is discussed and examples presented. (author)

  3. Public relations and the radiation processing industry

    Science.gov (United States)

    Coates, T. Donna

    The world's uneasiness and mistrust regarding anything nuclear has heightened in recent years due to events such as Chernobyl and Three Mile Island. Opinion polls and attitude surveys document the public's growing concern about issues such as the depletion of the ozone layer, the resulting greenhouse effect and exposure of our planet to cosmic radiation. Ultimately, such research reveals an underlying fear regarding the unseen impacts of modern technology on the environment and on human health. These concerns have obvious implications for the radiation processing industry, whose technology is nuclear based and not easily understood by the public. We have already seen organized nuclear opponents mobilize public anxiety, fear and misunderstanding in order to oppose the installation of radiation processing facilities and applications such as food irradiation. These opponents will no doubt try to strengthen resistance to our technology in the future. Opponents will attempt to convince the public that the risks to public and personal health and safety outweigh the benefits of our technology. We in the industry must head off any tendency for the public to see us as the "enemy". Our challenge is to counter public uneasiness and misunderstanding by effectively communicating the human benefits of our technology. Clearly it is a challenge we cannot afford to ignore.

  4. Public relations and the radiation processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Coates, T.D. (Nordion International Inc., Kanata, Ontario (Canada))

    1990-01-01

    The world's uneasiness and mistrust regarding anything nuclear has heightened in recent years due to events such as Chernobyl and Three Mile Island. Opinion polls and attitude surveys document the public's growing concern about issues such as the depletion of the ozone layer, the resulting greenhouse effect and exposure of our planet to cosmic radiation. Ultimately, such research reveals an underlying fear regarding the unseen impacts of modern technology on the environment and on human health. These concerns have obvious implications for the radiation processing industry, whose technology is nuclear based and not easily understood by the public. We have already seen organized nuclear opponents mobilize public anxiety, fear and misunderstanding in order to oppose the installation of radiation processing facilities and applications such as food irradiation. These opponents will no doubt try to strengthen resistance to our technology in the future. Opponents will attempt to convince the public that the risks to public and personal health and safety outweigh the benefits of our technology. We in the industry must head off any tendency for the public to see us as the ''enemy''. Our challenge is to counter public uneasiness and misunderstanding by effectively communicating the human benefits of our technology. (author).

  5. Status and future trends of radiation processing in Brazil

    International Nuclear Information System (INIS)

    Lugao, A.B.; Andrade, E; Silva, L.G.

    1998-01-01

    Electron-beam and gamma irradiation of polymers are widely applied in Brazil today. The main applications are: radio-induced crosslinking of wire and cable for automobile and appliance industry; heat shrinkable tubes for appliance, automobile and electronic; heat shrinkable packing for food processing industry; sterilization of medical supplies and so on. Nevertheless, there are only a few industrial facilities about 20 years old in full operation at present and there are some new low energy machines for food packing. The reason for such absence of investment in this area was studied and the relation between automobile and appliance production with radiation processing was fully demonstrated for Brazil case. In conclusion, it was shown that the industry of radiation processing of polymers is likely to experience a strong growth based on the continuous increase in the production of automobiles and appliances. The R and D activities of IPEN are an important support for developing the necessary technology and developing the necessary confidence in the radiation as tool for economical and social growth

  6. Status and future trends of radiation processing in Brazil

    Science.gov (United States)

    Lugão, A. B.; Andrade, E.; Silva, L. G.

    1998-06-01

    Electron-beam and gamma irradiation of polymers are widely applied in Brazil today. The main applications are: - radio-induced crosslinking of wire and cable for automobile and appliance industry; - heat shrinkable tubes for appliance, automobile and electronic; - heat shrinkable packing for food processing industry; - sterilization of medical supplies and so on. Nevertheless, there are only a few industrial facilities about 20 years old in full operation at present and there are some new low energy machines for food packing. The reason for such absence of investment in this area was studied and the relation between automobile and appliance production with radiation processing was fully demonstrated for Brazil case. In conclusion, it was shown that the industry of radiation processing of polymers is likely to experience a strong growth based on the continuous increase in the production of automobiles and appliances. The R&D activities of IPEN are an important support for developing the necessary technology and developing the necessary confidence in the radiation as tool for economical and social growth.

  7. EPR-dosimetry for radiation processing of food

    International Nuclear Information System (INIS)

    Peimel-Stuglik, Z.; Fabisiak, S.

    2002-01-01

    The usefulness of two, easy accessible alanine-polymer dosimeters to low (D ≤ 10 kGy) ionizing radiation dose measurements, were investigated. In both cases (ALANPOL from IChTJ and foil dosemeters from Gamma Service, Radeberg, Germany) the results were positive. EPR-alanine method based on the described dosimeters meets the requirements to use it in radiation processing of food. Thin foil dosemeters from Gamma Service are recommended mainly for dose distribution measurements. ALANPOL - for routine use. The advantage of ALANPOL is lower price, higher sensitivity and high resistance to unfavourable environmental conditions, including water. (author)

  8. Development of Radiation Processed Nano-Composite Blends and Nano-Coatings for Industrial Applications

    International Nuclear Information System (INIS)

    Dubey, K.A.; Kumar, Virendra; Bhardwaj, Yatender; Chaudhari, Chandrasekhar; Sarma, K.S.S.; Khader, Sheikh Abdul; Acharya, Satyanarayan

    2011-01-01

    Radiation processing of nanoparticle-filled polymer blends and coatings is expected to synergize the benefits of radiation processing and the flexibility of achieving various property combinations. High energy radiation can be utilized in a variety of ways to modify these systems. It can be used to crosslink the matrix, to compatibilize the blend components, to synthesize graft copolymer based compatibilizers, to improve interfacial bonding between the nanofiller/polymers or to freeze the morphology. Properties like flame retardency, permeability, abrasion resistance, biocompatibility and antibacterial activity can also be significantly affected by this composite approach. Due to the variety and quality of the product it promises, radiation processing of these mixed systems has been our core interest in the last few years. In the report, some of results on the radiation processing of SBR/EPDM blends and SBR/EPDM/MWNT nanocomposites are presented. (author)

  9. Development of Radiation Processed Nano-Composite Blends and Nano-Coatings for Industrial Applications

    Energy Technology Data Exchange (ETDEWEB)

    Dubey, K. A.; Kumar, Virendra; Bhardwaj, Yatender; Chaudhari, Chandrasekhar; Sarma, K. S.S.; Khader, Sheikh Abdul; Acharya, Satyanarayan [Bhabha Atomic Research Centre, Trombay, Mumbai (India)

    2011-07-01

    Radiation processing of nanoparticle-filled polymer blends and coatings is expected to synergize the benefits of radiation processing and the flexibility of achieving various property combinations. High energy radiation can be utilized in a variety of ways to modify these systems. It can be used to crosslink the matrix, to compatibilize the blend components, to synthesize graft copolymer based compatibilizers, to improve interfacial bonding between the nanofiller/polymers or to freeze the morphology. Properties like flame retardency, permeability, abrasion resistance, biocompatibility and antibacterial activity can also be significantly affected by this composite approach. Due to the variety and quality of the product it promises, radiation processing of these mixed systems has been our core interest in the last few years. In the report, some of results on the radiation processing of SBR/EPDM blends and SBR/EPDM/MWNT nanocomposites are presented. (author)

  10. An industrial radiation source for food processing

    International Nuclear Information System (INIS)

    Sadat, R.

    1986-01-01

    The scientific linacs realized by CGR MeV in France have been installed in several research centers, the medical accelerators of CGR MeV have been installed in radiotherapy centers all over the world, and the industrial linacs have been used for radiography in heavy industries. Based on the experience for 30 years, CGR MeV has realized a new industrial radiation source for food processing. CARIC is going to install a new machine of CGR MeV, CASSITRON, as the demand for radiation increased. This machine has been devised specially for industrial irradiation purpose. Its main features are security, simplicity and reliability, and it is easy to incorporate it into a production line. The use of CASSITRON for food industry, the ionizing effect on mechanically separated poultry meat, the capital and processing cost and others are explained. Only 10 % of medical disposable supplies is treated by ionizing energy in France. The irradiation for food decontamination, and that for industrial treatment are demanded. Therefore, CARIC is going to increase the capacity by installing a CASSITRON for sterilization. The capital and processing cost are shown. The start of operation is expected in March, 1986. At present, a CASSITRON is being installed in the SPI food processing factory, and starts operation in a few weeks. (Kako, I.)

  11. Prospects of using natural antioxidants in radiation processed food

    International Nuclear Information System (INIS)

    Kanatt, S.R.; Chander, Ramesh; Sharma, Arun

    2006-01-01

    Full text: Microbial contamination of food is a serious concern both for food producer and consumer. Radiation processing of food is one of the most effective technologies that can extend the shelf-life and eliminate pathogenic bacteria in food. However, wide acceptability of radiation processed food products will depend upon quality parameters such as oxidative changes, color stability and organoleptic attributes. Any food processing technique is known to accelerate lipid peroxidation and radiation processing is no exception. Irradiation does not adversely affect the overall nutritive value of food and the oxidative changes induced by irradiation are similar to those observed using conventional food processing methods. Combination of various processing conditions such as storage and cooking, results in accelerated oxidative deterioration. The growing demand for convenience foods and the evolving markets for pre cooked food, call for techniques to prevent lipid oxidation in prepared stored food. Products of lipid peroxidation adversely affect the color, flavor and texture of the food. It is therefore necessary to control these changes for better product development. Methods commonly employed by the food industry include the use of antioxidants. Presently, most of the antioxidants used are synthetic but consumer concern has become a driving force for exploring the use of natural antioxidants. The increase interest in substitution of synthetic antioxidants with natural antioxidants has fostered research on screening of plant materials in order to identify new compounds. We have investigated the antioxidant potential of several plant extracts, herbs and waste generated by the food industry, such as potato peel, banana peel, mango peel, mint, cinnamon extracts and chitosan. Mint extract was found to have the maximum antioxidant activity as tested by several in vitro antioxidant assays. The antioxidant activity of mint extract was comparable to that of BHT the commonly

  12. Application of radiation processing in Asia and the pacific region: focus on Malaysia

    International Nuclear Information System (INIS)

    Khairul Zaman, H.J.; Mohd Dahlan

    1995-01-01

    Applications of radiation processing in Malaysia and other developing countries in Asia and the Pacific region is increasing as the countries move toward industrialisation. At present, there are more than 85 gamma facilities and 334 electron accelerators in Asia and the Pacific region which are mainly in Japan, Rep. of Korea and China. The main applications which are in the interest of the region are radiation sterilisation of medical products; radiation crosslinking of wire and cable, heat shrinkable film and tube, and foam; radiation euring of surface coatings, printing inks and adhesive; radiation vulcanisation of natural rubber latex; radiation processing of agro-industrial waste; radiation treatment of sewage sludge and municipal waste; food irradiation; tissue grafts and radiation synthesis of bioactive materials. (author)

  13. Application of radiation processing in Asia and the Pacific region: focus on Malaysia

    International Nuclear Information System (INIS)

    Dahlan, K.Z.H.M.

    1995-01-01

    Applications of radiation processing in Malaysia and other developing countries in Asia and the Pacific region is increasing as the countries move toward industrialisation. At present, there are more than 85 gamma facilities and 334 electron accelerators in Asia and the Pacific region which are mainly in Japan, Rep. of Korea and China. The main applications which are in the interest of the region are radiation sterilisation of medical products; radiation crosslinking of wire and cable, heat shrinkable film and tube, and foam; radiation curing of surface coatings, printing inks and adhesive; radiation vulcanisation of natural rubber latex; radiation processing of agro-industrial waste; radiation treatment of sewage sludge and municipal waste; food irradiation; tissue grafts and radiation synthesis of bioactive materials. (author)

  14. Radiation Monitoring System in Advanced Spent Fuel Conditioning Process Facility

    Energy Technology Data Exchange (ETDEWEB)

    You, Gil Sung; Kook, D. H.; Choung, W. M.; Ku, J. H.; Cho, I. J.; You, G. S.; Kwon, K. C.; Lee, W. K.; Lee, E. P

    2006-09-15

    The Advanced spent fuel Conditioning Process is under development for effective management of spent fuel by converting UO{sub 2} into U-metal. For demonstration of this process, {alpha}-{gamma} type new hot cell was built in the IMEF basement . To secure against radiation hazard, this facility needs radiation monitoring system which will observe the entire operating area before the hot cell and service area at back of it. This system consists of 7 parts; Area Monitor for {gamma}-ray, Room Air Monitor for particulate and iodine in both area, Hot cell Monitor for hot cell inside high radiation and rear door interlock, Duct Monitor for particulate of outlet ventilation, Iodine Monitor for iodine of outlet duct, CCTV for watching workers and material movement, Server for management of whole monitoring system. After installation and test of this, radiation monitoring system will be expected to assist the successful ACP demonstration.

  15. Radiation Monitoring System in Advanced Spent Fuel Conditioning Process Facility

    International Nuclear Information System (INIS)

    You, Gil Sung; Kook, D. H.; Choung, W. M.; Ku, J. H.; Cho, I. J.; You, G. S.; Kwon, K. C.; Lee, W. K.; Lee, E. P.

    2006-09-01

    The Advanced spent fuel Conditioning Process is under development for effective management of spent fuel by converting UO 2 into U-metal. For demonstration of this process, α-γ type new hot cell was built in the IMEF basement . To secure against radiation hazard, this facility needs radiation monitoring system which will observe the entire operating area before the hot cell and service area at back of it. This system consists of 7 parts; Area Monitor for γ-ray, Room Air Monitor for particulate and iodine in both area, Hot cell Monitor for hot cell inside high radiation and rear door interlock, Duct Monitor for particulate of outlet ventilation, Iodine Monitor for iodine of outlet duct, CCTV for watching workers and material movement, Server for management of whole monitoring system. After installation and test of this, radiation monitoring system will be expected to assist the successful ACP demonstration

  16. Additives in UV and ionising radiation grafting and curing processes

    International Nuclear Information System (INIS)

    Garnett, J.L.; Ng, L.T.; Viengkhou, V.

    1998-01-01

    Full text: Curing of polymers induced by both UV and ionising radiation are now established technologies. Currently both systems are predominantly based on acrylate chemistry. UV processes use photoinitiators to achieve fast polymerisation. In the proposed paper the significance of the occurrence of concurrent grafting with cure will be examined. particularly with respect to the recycling of finished product. Basic studies on grafting initiated by UV and ionising radiation will be discussed. Polar methyl methacrylate (MMA) and non-polar styrene will be used as representative monomers with cellulose and propylene typifying the backbone polymers. The additives chosen for examination in this study are predominantly components used in radiation curing formulations since grafting and curing are known to be mechanically related. The additives used were mineral acid, photoinitiators, vinyl ethers, oligomers, polyfunctional monomers including multifunctional acrylates (MFAs) and methacrylates (MFMAs). For the first time the use of charge transfer complexes in the Mulliken sense as additives in radiation grafting will be discussed. The CT complexes themselves, being monomers, have also been grafted to the above polymers. Recent developments with excimer laser sources for initiating these processes will be discussed, especially the use of non-acrylate chemistry. Excimer laser sources are shown to complement conventional UV and ionising radiation and are photoinitiator free. Mechanisms for the above grafting and curing processes will be outlined

  17. Application of Glycine-TTC dosimeter in gamma radiation processing facility

    International Nuclear Information System (INIS)

    Shinde, S.H.; Mondal, S.; Kulkarni, M.S.

    2018-01-01

    Glycine-TTC dosimeter was found to have a useful dose range of 5 to 30 kGy using spectro-photometric read-out method. Potential use of this dosimeter was demonstrated by measuring dose-rate in gamma chamber GC 900. The aim of the present study was to verify the performance of this dosimeter in actual industrial processing conditions encountered in radiation processing facility such as Gamma Radiation Processing Plant for Spices (GRPPS), BRIT, Vashi. Accordingly, glycine-TTC dosimeters were irradiated along with routine dosimeter viz. ceric-cerous of GRPPS and reference standard dosimeter viz. alanine EPR

  18. Evaluation of the modified nanoclay effect on the vulcanization of SBR through rheometric curve and DSC;Avaliacao do efeito de nanoargila modificada na vulcanizacao de SBR atraves da curva reometrica e DSC

    Energy Technology Data Exchange (ETDEWEB)

    Forte, Maria Madalena C.; Brito, Karin J.S., E-mail: mmcforte@ufrgs.b [Universidade Federal do Rio Grande do Sul (PPGEM/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Gheller Junior, Jordao [SENAI, Sao Leopoldo, RS (Brazil). Centro Tecnologico de Polimeros

    2009-07-01

    Rubber nanocomposites with nanoclays organically modified by quaternary ammonium salts may have the curing features modified significantly, since the salts may act on the rubber cure system. The aim of this work is to evaluate the influences of an organically modified montmorillonite (OMMT) on the curing reaction of an SBR (styrene butadiene rubber) with sulfur. The SBR/OMMT nanocomposites were prepared by co-coagulating SBR latex and Cloisite{sup R} 20A aqueous suspension at different nanoclay concentrations. The OMMT effect on the sulfur curing reaction was evaluated by the rheometric curve using a rheometer type RPA (Rubber Process Analyzer) and the heat of vulcanization (DELTAH{sub v}) using Differential Scanning Calorimetry (DSC). The evaluation of the clay nanolayers dispersion in the SBR matrix was accomplished by x-ray diffraction (XRD) analysis. (author)

  19. Application of radiation technology to sewage sludge processing: A review

    International Nuclear Information System (INIS)

    Wang Jianlong; Wang Jiazhuo

    2007-01-01

    Sewage sludge is unwanted residual solid wastes generated in wastewater treatment and its management is one of the most critical environmental issues of today. The treatment and disposal of sludge contribute a considerable proportion of the cost for running a wastewater treatment plant. The increasing amount of swage sludge and more and more legislative regulation of its disposal have stimulated the need for developing new technologies to process sewage sludge efficiently and economically. One ideal consideration is to recycle it after proper treatment. Radiation technology is regarded to be a promising alternative for its high efficiency in pathogen inactivation, organic pollutants oxidation, odor nuisance elimination and some other characteristics enhancement, which will facilitate the down-stream process of sludge treatment and disposal. Here we present a brief review of application of radiation technology on sewage sludge processing. Some basic information of two currently available irradiation systems and fundamental radiation chemistry are introduced firstly; then the world-wide application of this promising technology is reviewed; various effects of radiation on sludge is discussed in detail; and some concluding remarks are given and some future directions are also proposed

  20. Studies and Development of Radiation Processed Nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Varshney, Lalit; Sabharwal, Sunil; Francis, Sanju; Biswal, Jayashree [Radiation Technology Development Section, Bhabha Atomic Research Centre, Mumbai (India)

    2009-07-01

    Nanotechnology is the emerging technology that deals with processing, manipulating and manufacturing devices and products at the microscopic scale of molecules or atoms with structures smaller than 100 nanometers. Realizing its potential, Government of India spending on R&D in nanotechnology has gone up by an order of magnitude in last 5 years through various national and international programs. High energy gamma radiation and electron beams could be a useful tool to create innovative and newer nano-materials for various applications in medical field for treatment and detection purposes. Considering its certain advantage for producing nano-materials, radiation technology will play a crucial role in development of such materials. Research and development in the area of nano--particles on polymer films, hydrogels, silica particles and their nano-clusters using radiation technology could be a possible route for development of new functional nano-materials. (author)

  1. Studies and Development of Radiation Processed Nanomaterials

    International Nuclear Information System (INIS)

    Varshney, Lalit; Sabharwal, Sunil; Francis, Sanju; Biswal, Jayashree

    2009-01-01

    Nanotechnology is the emerging technology that deals with processing, manipulating and manufacturing devices and products at the microscopic scale of molecules or atoms with structures smaller than 100 nanometers. Realizing its potential, Government of India spending on R&D in nanotechnology has gone up by an order of magnitude in last 5 years through various national and international programs. High energy gamma radiation and electron beams could be a useful tool to create innovative and newer nano-materials for various applications in medical field for treatment and detection purposes. Considering its certain advantage for producing nano-materials, radiation technology will play a crucial role in development of such materials. Research and development in the area of nano--particles on polymer films, hydrogels, silica particles and their nano-clusters using radiation technology could be a possible route for development of new functional nano-materials. (author)

  2. Blendas PVC/NBR por processamento reativo II: caracterização físico-mecânica e morfológica PVC/NBR blends by reactive processing II: physical-mechanical and morphological characterization

    Directory of Open Access Journals (Sweden)

    Fábio R. Passador

    2008-06-01

    Full Text Available Vulcanização dinâmica é o processo de vulcanização de um elastômero durante a mistura no estado fundido com um termoplástico. Por este processo, o elastômero adquire resistência mecânica através do aumento do módulo de elasticidade, dureza, resistência à fadiga e abrasão. Neste trabalho, buscou-se avaliar as propriedades físico-mecânicas e as características morfológicas de blendas poliméricas constituídas de Poli(cloreto de Vinila e borracha nitrílica, PVC/NBR, obtidas por processamento reativo. A vulcanização dinâmica melhorou o desempenho mecânico destas blendas, notadamente pelo aumento da rigidez desses sistemas, sendo obtido um aumento de 205% no módulo elástico de blendas vulcanizadas com 10% em massa de NBR em comparação com blendas convencionais. Através de análises de MEV, revelou-se uma morfologia bifásica, sendo que a formação de ligações cruzadas deve ocorrer preferencialmente no interior das partículas do elastômero, contribuindo para o aumento na resistência mecânica final das blendas obtidas por processamento reativo.Dynamic vulcanization is a process of vulcanization of an elastomer during melt mixing with a thermoplastic. This process increases the mechanical resistance of elastomers through the increase of elastic modulus, hardness and abrasion/fatigue resistance. In this study, it was evaluated the physical-mechanical and morphological behaviors of the PVC/NBR blends obtained by reactive processing. The dynamic vulcanized blends have a better performance compared to the similar conventional ones. It was observed an increase of 205% in the elastic modulus to the dynamic vulcanized blend PVC/NBR (90/10 compared with the conventional blends. The morphology of the blends examined by scanning electron microscopy evidenced the crosslinking formation only in the elastomeric phase. The vulcanized rubber particles are responsible by the increase of stiffness and consequently displayed better

  3. Proceedings of the Scientific Meeting on Application of Isotopes and Radiation: Book 2. Chemistry, Environment, Radiation Process, And Industry

    Energy Technology Data Exchange (ETDEWEB)

    Suhadi, F; Sisworo, E L; Maha, M; Ismachin, M; Hilmy, N; Sumatra, M; Mugiono,; Wandowo,; Soebianto, Y S [Center for Application of Isotopes and Radiation, National Atomic Energy Agency, Jakarta (Indonesia)

    1998-07-01

    The aim of the 10th Meeting of the Isotope and Radiation Application is to disseminate the result of research on application of nuclear techniques on agriculture, animal, biology, chemistry, environment, radiation process and industry. The meeting was held in Jakarta, 18-19 February 1998, and there were 6 invited papers and 52 papers indexed individually. This proceeding is divided by two volumes. Volume I and volume II consists of agriculture, animal, biology and chemistry, environment, radiation process and industry, respectively.(ID)

  4. Proceedings of the Scientific Meeting on Application of Isotopes and Radiation: Book 2. Chemistry, Environment, Radiation Process, And Industry

    International Nuclear Information System (INIS)

    Suhadi, F.; Sisworo, E.L.; Maha, M.; Ismachin, M.; Hilmy, N.; Sumatra, M.; Mugiono; Wandowo; Soebianto, Y.S.

    1998-01-01

    The aim of the 10th Meeting of the Isotope and Radiation Application is to disseminate the result of research on application of nuclear techniques on agriculture, animal, biology, chemistry, environment, radiation process and industry. The meeting was held in Jakarta, 18-19 February 1998, and there were 6 invited papers and 52 papers indexed individually. This proceeding is divided by two volumes. Volume I and volume II consists of agriculture, animal, biology and chemistry, environment, radiation process and industry, respectively.(ID)

  5. Collisional and radiative processes in fluorescent lamps

    International Nuclear Information System (INIS)

    Lister, Graeme G.

    2003-01-01

    Since electrode life is the major limiting factor in operating fluorescent lamps, many lighting companies have introduced 'electrodeless' fluorescent lamps, using inductively coupled discharges. These lamps often operate at much higher power loadings than standard lamps and numerical models have not been successful in reproducing experimental measurements in the parameter ranges of interest. A comprehensive research program was undertaken to study the fundamental physical processes of these discharges, co-funded by the Electric Power Research Institute (EPRI) and OSRAM SYLVANIA under the name of ALITE. The program included experiments and modeling of radiation transport, computations of electron-atom and atom-atom cross sections and the first comprehensive power balance studies of a highly loaded fluorescent lamp. Results from the program and their importance to the understanding of the physics of fluorescent lamps are discussed, with particular emphasis on the important collisional and radiative processes. Comparisons between results of experimental measurements and numerical models are presented

  6. Radiation sterilization: an industrial process

    International Nuclear Information System (INIS)

    Ley, F.J.

    1975-01-01

    A new dimension has been added to the use of radiation in the medical field with the introduction of radiation as a sterilizing agent. Its use in diagnosis through radioactive tracers or X-rays and in therapy administered with the most sophisticated of electrical machines or radioisotope units, is familiar in the hospital world, being well established therein. In contrast, the application of radiation sterilization is in industry where the installation of large radiation sources is already commonplace in many countries. The beginnings in the early 1950's centered on the Van de Graaff machine and linear accelerators and the pioneering efforts of Ethicon Inc. here in the United States must be recognized. However, although sterilization with electron beams is still current practice in a number of plants, the use of gamma rays from cobalt-60 is preferred. The first steps in this direction were taken by the U.K.A.E.A. which, in common with similar organizations elsewhere, was attempting to exploit the tremendous potential for cobalt-60 production arising through the rapid construction of nuclear reactors. The first full-scale commercial gamma plant was commissioned in the U.K. in 1960. It reached a loading of 500,000 curies before its demolition after twelve years of operation. The process gained rapid acceptance within industry and approval by health authorities because it provided a ''cold'' sterilization method combining the property of lethal effect with penetration. Its immediate impact occurred in the introduction of disposable products making it possible, for example, to use heat-labile plastics and new packaging materials and package designs. Certainly, the technique has proved complementary to sterilization methods based on heat and to the use of chemical agents, in particular ethylene oxide gas

  7. Radiation processing for environmental-friendly industrial applications

    International Nuclear Information System (INIS)

    Majali, A.B.; Sabharwal, S.

    1997-01-01

    The Isotope Division of BARC is equipped with a 2-MeV electron beam (EB) accelerator and a 70,000 Ci Cobalt-60 source: these are mainly utilized to develop technologies of interest to our industries and needs. These include development of polyethylene 'O' rings having dimensional stability above the melting point, radiation degradation of PTFE and enhancement of colour in diamonds. The viscose rayon industry is an important industry in India. This industry faces stiff regulations from environmental pollution control agencies primarily due to the emission of toxic sulphur containing gases, and is in search of ways to reduce the pollution levels associated with the process. The irradiation of cellulose with ionizing radiation results in cellulose activation and reduction in the degree of polymerization (DP). There is a keen interest in utilizing radiation technology in viscose rayon production. We have utilized the 2-MeV electron beam accelerator for reducing the degree of polymerization (DP) of paper pulp. Laboratory scale tests have been carried out to standardize the conditions for processing of pulp having desired degree of polymerization. Our studies show that the use of irradiated pulp can significantly reduce the consumption of CS 2 and be beneficial in reducing pollution associated with the process. An electron-beam irradiation based process has been developed to convert the PTFE waste into a low molecular weight (1x10 4 -1x10 5 ) PTFE powder that can be easily processed into a fine micropowder having industrial demand. Even carbon or metal filled PTFE has been recycled using this process. The conventional method of crosslinking linear polymers by thermo-clinical method leads to the formation of homogeneously crosslinked materials which are extremely slow for industrial applications. Electron beam irradiation has been used to create inhomogeneous crosslinking of a temperature-sensitive polymer- poly(vinyl methyl ether)(PVME) so as to produce a fast response

  8. Estimation of radiation dose received by the radiation worker during 18F FDG injection process

    International Nuclear Information System (INIS)

    Jha, Ashish Kumar; Zade, Anand; Rangarajan, Venkatesh

    2011-01-01

    The radiation dosimetric literature concerning the medical and non-medical personnel working in nuclear medicine departments are limited, particularly radiation doses received by radiation worker in nuclear medicine department during positron emission tomography (PET) radiopharmaceutical injection process. This is of interest and concern for the personnel. To measure the radiation dose received by the staff involved in injection process of Fluorine-18 Fluorodeoxyglucose (FDG). The effective whole body doses to the radiation workers involved in injections of 1511 patients over a period of 10 weeks were evaluated using pocket dosimeter. Each patient was injected with 5 MBq/kg of 18 F FDG. The 18 F-FDG injection protocol followed in our department is as follows. The technologist dispenses the dose to be injected and records the pre-injection activity. The nursing staff members then secure an intravenous catheter. The nuclear medicine physicians/residents inject the dose on a rotation basis in accordance with ALARA principle. After the injection of the tracer, the nursing staff members flush the intravenous catheter. The person who injected the tracer then measures the post-injection residual dose in the syringe. The mean effective whole body doses per injection for the staff were the following: Nurses received 1.44 ± 0.22 μSv/injection (3.71 ± 0.48 nSv/MBq), for doctors the dose values were 2.44 ± 0.25 μSv/injection (6.29 ± 0.49 nSv/MBq) and for technologists the doses were 0.61 ± 0.10 μSv/injection (1.58 ± 0.21 nSv/MBq). It was seen that the mean effective whole body dose per injection of our positron emission tomography/computed tomography (PET/CT) staff who were involved in the 18 F-FDG injection process was maximum for doctors (54.34% differential doses), followed by nurses (32.02% differential doses) and technologist (13.64% differential doses). This study confirms that low levels of radiation dose are received by staff during 18 F-FDG injection and

  9. Present status and expected progress in radiation processing dosimetry

    DEFF Research Database (Denmark)

    Kovács, A.; Miller, A.

    2004-01-01

    The paper describes the present status of radiation processing dosimetry including the methods used most widely in gamma- and electron processing as well as the new methods under development or introduction. The recent trends with respect to calibrationof routine dosimetry systems as well...

  10. Dye film dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Humphreys, J.C.; McLaughlin, W.L.

    1981-01-01

    Commercially available plastic films containing dyes or dye precursors are convenient dosimeters and imaging media for electron beams or photons used for industrial radiation processing. As ''grainless'' imaging systems having thicknesses down to a few micrometers, they provide high spatial resolution for determining detailed absorbed dose distributions through microdensitometric analysis. The radiation absorption properties of these systems are adjusted by changing film composition so that the dosimeter materials can be made to simulate the material of interest undergoing irradiation. Other advantages include long-term stability, dose-rate independence, and ease of use and calibration. Radiochromic dye films with thicknesses varying from 0.005 to 1 mm are presently used to monitor electron-beam or gamma-ray doses from 10 to 10 5 Gy (10 3 to 10 7 rad), typical of those encountered in medical applications, radiation curing of polymeric composites, wire and cable insulation, shrinkable plastic tubing and film, as well as sterilization of medical supplies and treatment of municipal and industrial wastes. An NBS calibration service to industry involves the traceability of standard 60 Co gamma ray absorbed dose measurements by means of these films employed as transfer standards

  11. Development of Quantum Devices and Algorithms for Radiation Detection and Radiation Signal Processing

    International Nuclear Information System (INIS)

    El Tokhy, M.E.S.M.E.S.

    2012-01-01

    The main functions of spectroscopy system are signal detection, filtering and amplification, pileup detection and recovery, dead time correction, amplitude analysis and energy spectrum analysis. Safeguards isotopic measurements require the best spectrometer systems with excellent resolution, stability, efficiency and throughput. However, the resolution and throughput, which depend mainly on the detector, amplifier and the analog-to-digital converter (ADC), can still be improved. These modules have been in continuous development and improvement. For this reason we are interested with both the development of quantum detectors and efficient algorithms of the digital processing measurement. Therefore, the main objective of this thesis is concentrated on both 1. Study quantum dot (QD) devices behaviors under gamma radiation 2. Development of efficient algorithms for handling problems of gamma-ray spectroscopy For gamma radiation detection, a detailed study of nanotechnology QD sources and infrared photodetectors (QDIP) for gamma radiation detection is introduced. There are two different types of quantum scintillator detectors, which dominate the area of ionizing radiation measurements. These detectors are QD scintillator detectors and QDIP scintillator detectors. By comparison with traditional systems, quantum systems have less mass, require less volume, and consume less power. These factors are increasing the need for efficient detector for gamma-ray applications such as gamma-ray spectroscopy. Consequently, the nanocomposite materials based on semiconductor quantum dots has potential for radiation detection via scintillation was demonstrated in the literature. Therefore, this thesis presents a theoretical analysis for the characteristics of QD sources and infrared photodetectors (QDIPs). A model of QD sources under incident gamma radiation detection is developed. A novel methodology is introduced to characterize the effect of gamma radiation on QD devices. The rate

  12. Twenty new ISO standards on dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Farrar IV, H.

    2000-01-01

    Twenty standards on essentially all aspects of dosimetry for radiation processing were published as new ISO standards in December 1998. The standards are based on 20 standard practices and guides developed over the past 14 years by Subcommittee E10.01 of the American Society for Testing and Materials (ASTM). The transformation to ISO standards using the 'fast track' process under ISO Technical Committee 85 (ISO/TC85) commenced in 1995 and resulted in some overlap of technical information between three of the new standards and the existing ISO Standard 11137 Sterilization of health care products - Requirements for validation and routine control - Radiation sterilization. Although the technical information in these four standards was consistent, compromise wording in the scopes of the three new ISO standards to establish precedence for use were adopted. Two of the new ISO standards are specifically for food irradiation applications, but the majority apply to all forms of gamma, X-ray, and electron beam radiation processing, including dosimetry for sterilization of health care products and the radiation processing of fruit, vegetables, meats, spices, processed foods, plastics, inks, medical wastes, and paper. Most of the standards provide exact procedures for using individual dosimetry systems or for characterizing various types of irradiation facilities, but one covers the selection and calibration of dosimetry systems, and another covers the treatment of uncertainties using the new ISO Type A and Type B evaluations. Unfortunately, nine of the 20 standards just adopted by the ISO are not the most recent versions of these standards and are therefore already out of date. To help solve this problem, efforts are being made to develop procedures to coordinate the ASTM and ISO development and revision processes for these and future ASTM-originating dosimetry standards. In the meantime, an additional four dosimetry standards have recently been published by the ASTM but have

  13. Radiation microbiology relevant to radiation processing

    International Nuclear Information System (INIS)

    Tallentire, A.

    1979-01-01

    The subject is discussed under the following headings: typical background studies involving laboratory models (measurement of radiation responses of different organisms, alone or on or in products; isolation of radiation resistant organisms from products and product environments; measurement of levels of preirradiation microbial contamination ('bioburden')); supplementary studies involving naturally occurring microbial contaminants (unit medical products; microbiological quality assurance; products in bulk; animal diet study). (U.K.)

  14. PRELIMINARY RESULTS IN SYNCHROTRON X-RAY DIFFRACTION MEASUREMENTS OF RUBBER COMPOSITES STRUCTURE BEFORE AND AFTER EXPOSURE TO HYDROGEN

    Directory of Open Access Journals (Sweden)

    Francesca Cosmi

    2011-05-01

    Full Text Available In future years, fuel cells are expected to represent a promising technology as a source of heat and electricity in buildings and of electrical power for vehicles, since fossil fuels are exhausting and significantly degrade air quality. It is well known that, when exposed to a hydrogen environment, hydrogen embrittlerment may affect materials such as iron and steel. But these are not the only materials that are used for hydrogen equipment. In particular, the rubber materials used for O–rings that seal high pressure hydrogen gas equipment show problems of internal fracture, called blister fracture, when the gas is rapidly decompressed. As many different kinds of fillers can be used, in this work we started to investigate the influence of the type of filler on the rubber composites structure, by means of X-ray diffraction measurements performed at the Elettra synchrotron radiation facility in Trieste. In this preliminary study, three kinds of samples were analyzed before and after exposure to hydrogen: Sulphur vulcanized EPDM, Peroxide vulcanized EPDM and Sulphur vulcanized NBR. While Peroxide vulcanized samples did not show significant differences in the diffraction pattern, changes could be detected in the cristalline form of Sulfure vulcanized rubber.

  15. Radiation processing of agricultural products: status and potential contribution to a cleaner environment

    International Nuclear Information System (INIS)

    Lapidot, M.

    1979-01-01

    The current status of radiation processing of agricultural products is briefly reviewed with special regard to those processes which may contribute to a cleaner environment. Radurization of poultry feed and poultry meat is shown to be a major contributor to the reduction of a significant public health problem-salmonellosis. Radiation sterilized animal feeds can be produced by processing garbage - a major environmental pollutant. Radicidation and radappertization are effective processes in the treatment of sludges and waste water, to prevent pollution of seas or ground. Radiation processes can effectively replace fungicides and insecticides in the treatment of agricultural crops and thus reduce environmental pollution. (author)

  16. Real-time information and processing system for radiation protection

    International Nuclear Information System (INIS)

    Oprea, I.; Oprea, M.; Stoica, M.; Badea, E.; Guta, V.

    1999-01-01

    The real-time information and processing system has as main task to record, collect, process and transmit the radiation level and weather data, being proposed for radiation protection, environmental monitoring around nuclear facilities and for civil defence. Such a system can offer information in order to provide mapping, data base, modelling and communication and to assess the consequences of nuclear accidents. The system incorporates a number of stationary or mobile radiation monitoring equipment, weather parameter measuring station, a GIS-based information processing center and the communication network, all running on a real-time operating system. It provides the automatic data collection on-line and off-line, remote diagnostic, advanced presentation techniques, including a graphically oriented executive support, which has the ability to respond to an emergency by geographical representation of the hazard zones on the map.The system can be integrated into national or international environmental monitoring systems, being based on local intelligent measuring and transmission units, simultaneous processing and data presentation using a real-time operating system for PC and geographical information system (GIS). Such an integrated system is composed of independent applications operating under the same computer, which is capable to improve the protection of the population and decision makers efforts, updating the remote GIS data base. All information can be managed directly from the map by multilevel data retrieving and presentation by using on-line dynamic evolution of the events, environment information, evacuation optimization, image and voice processing

  17. Recent advances in radiation processing of food

    International Nuclear Information System (INIS)

    Sharma, Arun

    2013-01-01

    Commercial application of radiation technology for food processing started in the nineties after it was approved by FAO/IAEA/WHO and Codex Alimentarius Commission in the eighties. Sanitary applications were initially explored commercially with microbial decontamination of spices and dry ingredients as the primary commodities to be processed on a large scale. Subsequently, with the emergence of E.coli O157:H7 as the potential food poisoning risk in ground beef, irradiation of meat was initiated in the late nineties in the USA. Since then irradiation, has become a very useful food safety tool and the technology has been approved for addressing food safety risks in moluscan shellfish and vegetables like lettuce, spinach, and more recently for raw uncooked meat by USFDA. Phytosanitary applications assumed importance after USFDA approved irradiation as a method of phytosanitary treatment and subsequent endorsement of the process by International Plant Protection Convention (IPPC) in 2003. These approvals were responsible for development of international trade in agricultural commodities. The first to demonstrate the feasibility of the process were India and Australia, the countries that exported mangoes to New Zealand and USA, respectively. As far as the source of radiation is concerned, the world is slowly moving towards deployment of machine sources, thereby reducing its dependence on radioisotopes for commercial irradiation. (author)

  18. FNCA guideline on development of hydrogel and oligosaccharides by radiation processing

    International Nuclear Information System (INIS)

    Kudo, Hisaaki; Yoshii, Fumio; Kume, Tamikazu

    2009-10-01

    This report summarizes the current status of development of hydrogel and oligosaccharides by radiation (electron beams and gamma rays) processing in Asian countries, as an outcome of activities of the FNCA (Forum for Nuclear Co-operation in Asia)-industry group during the phase 2 (2006-2008), as one of FNCA Guidelines. The nine countries, Bangladesh (since 2007), China, Indonesia, Japan, Korea, Malaysia, Philippines, Thailand and Vietnam, participates in the phase 2 of the FNCA-industry group, focusing on radiation processing of natural polymers. Participating countries have been studying radiation processing of natural polymers such as chitosan from shrimp/crab shells and carrageenan taken from seaweeds, in terms of cross-linking for gel and degradation for oligosaccharides. The former obtains hydrogel which can absorb a lot of water, and application for wound dressing and super water absorbent in the fields of medical and environmental conservation are expected. The latter obtained oligosaccharides have functions as growth promoter and elicitor activator of plants, sea-creatures and livestocks etc., and application in the fields of agri- and aqua- cultures are expected. This Guideline consists of 3 parts; part 1 describes the outline of radiation chemistry of polymers; part 2 compiles the protocols of versatile applications; part 3 refers the examples of cost analysis and current status of the technology. This Guideline would facilitate development, commercialization and technical transfer to end-users of radiation processing of natural polymers. (author)

  19. Collisional and radiative processes in high-pressure discharge plasmas

    Science.gov (United States)

    Becker, Kurt H.; Kurunczi, Peter F.; Schoenbach, Karl H.

    2002-05-01

    Discharge plasmas at high pressures (up to and exceeding atmospheric pressure), where single collision conditions no longer prevail, provide a fertile environment for the experimental study of collisions and radiative processes dominated by (i) step-wise processes, i.e., the excitation of an already excited atomic/molecular state and by (ii) three-body collisions leading, for instance, to the formation of excimers. The dominance of collisional and radiative processes beyond binary collisions involving ground-state atoms and molecules in such environments allows for many interesting applications of high-pressure plasmas such as high power lasers, opening switches, novel plasma processing applications and sputtering, absorbers and reflectors for electromagnetic waves, remediation of pollutants and waste streams, and excimer lamps and other noncoherent vacuum-ultraviolet light sources. Here recent progress is summarized in the use of hollow cathode discharge devices with hole dimensions in the range 0.1-0.5 mm for the generation of vacuum-ultraviolet light.

  20. IAEA Conference on Large Radiation Sources in Industry (Warsaw 1959): Which technologies of radiation processing survived and why?

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1999-01-01

    The IAEA has organized in Warsaw an International Conference on Large Radiation Sources in Industry from 8 to 12 September 1959. Proceedings of the Conference have been published in two volumes of summary amount of 925 pages. This report presents analysis, which technologies presented at the Conference have survived and why. The analysis is interesting because already in the fifties practically full range of possibilities of radiation processing was explored, and partially implemented. Not many new technologies were presented at the next IAEA Conferences on the same theme. Already at the time of the Warsaw Conference an important role of economy of the technology has recognized. The present report selects the achievements of the Conference into two groups: the first concerns technologies which have not been implemented in the next decades and the second group which is the basis of highly profitable, unsubsidized commercial production. The criterion of belonging of the technology to the second group, is the value of the quotient of the cost of the ready, saleable product diminished by the cost of a raw material before processing, to the expense of radiation processing, being the sum of irradiation cost and such operations as transportation of the object to and from the irradiation facility. Low value of the quotient, as compared to successful technologies is prophesying badly as concerns the future of the commercial proposal. A special position among objects of radiation processing is occupied by radiation processing technologies direct towards the protection or improving of the environment. Market economy does not apply here and the implementation has to be subsidized. (author)

  1. Radiation processing applications in the Czechoslovak water treatment technologies

    Science.gov (United States)

    Vacek, K.; Pastuszek, F.; Sedláček, M.

    The regeneration of biologically clogged water wells by radiation proved to be a successful and economically beneficial process among other promising applications of ionizing radiation in the water supply technology. The application conditions and experience are mentioned. The potential pathogenic Mycobacteria occuring in the warm washing and bathing water are resistant against usual chlorine and ozone concentrations. The radiation sensitivity of Mycobacteria allowed to suggest a device for their destroying by radiation. Some toxic substances in the underground water can be efficiently degraded by gamma radiation directly in the wells drilled as a hydraulic barrier surrounding the contaminated land area. Substantial decrease of CN - concentration and C.O.D. value was observed in water pumped from such well equipped with cobalt sources and charcoal. The removing of pathogenic contamination remains to be the main goal of radiation processing in the water purification technologies. The decrease of liquid sludge specific filter resistance and sedimentation acceleration by irradiation have a minor technological importance. The hygienization of sludge cake from the mechanical belt filter press by electron beam appears to be the optimum application in the Czechoslovak conditions. The potatoes and barley crop yields from experimental plots treated with sludge were higher in comparison with using the manure. Biological sludge from the municipal and food industry water purification plants contains nutritive components. The proper hygienization is a necessary condition for using them as a livestock feed supplement. Feeding experiments with broilers and pigs confirmed the possibility of partial (e.g. 50%) replacement of soya-, bone- or fish flour in feed mixtures by dried sludge hygienized either by heat or by the irradiation.

  2. Radiation processing applications in the Czechoslovak water treatment technologies

    International Nuclear Information System (INIS)

    Vacek, K.; Pastuszek, F.; Sedlacek, M.

    1986-01-01

    The regeneration of biologically clogged water wells by radiation proved to be a successful and economically beneficial process among other promising applications of ionizing radiation in the water supply technology. The application conditions and experience are mentioned. The potential pathogenic Mycobacteria occuring in the warm washing and bathing water are resistant against usual chlorine and ozone concentrations. The radiation sensitivity of Mycobacteria allowed to suggest a device for their destroying by radiation. Some toxic substances in the underground water can be efficiently degraded by gamma radiation directly in the wells drilled as a hydraulic barrier surrounding the contaminated land area. Substantial decrease of CN - concentration and C.O.D. value was observed in water pumped from such well equipped with cobalt sources and charcoal. The removing of pathogenic contamination remains to be the main goal of radiation processing in the water purification technologies. The decrease of liquid sludge specific filter resistance and sedimentation acceleration by irradiation have a minor technological importance. The hygienization of sludge cake from the mechanical belt filter press by electron beam appears to be the optimum application in the Czechoslovak conditions. The potatoes and barley crop yields from experimental plots treated with sludge were higher in comparison with using the manure. Biological sludge from the municipal and food industry water purification plants contains nutritive components. The proper hygienization is a necessary condition for using them as a livestock feed supplement. Feeding experiments with broilers and pigs confirmed the possibility of partial (e.g. 50%) replacement of soya-, bone, or fish flour in feed mixtures by dried sludge hygienized either by heat or by the irradiation. (author)

  3. VII International scientific conference Radiation-thermal effects and processes in inorganic materials. Proceedings

    International Nuclear Information System (INIS)

    2010-01-01

    In the collection there are the reports of the VII International scientific conference and the VII All-Russian school-conference Radiation-thermal effects and processes in inorganic materials which were conducted on October 2-10, 2010, in Tomsk. The reports deal with new developments of charged particles high-intensity beam sources, high-temperature metrology of high-current beams and work materials, radiation-thermal stimulated effects and processes in inorganic materials, physical basics of technological processes, radiation-thermal technologies and equipment for their realization, allied branches of science and technology, specifically, nanotechnologies [ru

  4. Radiation- and photoinduced processes in glass-like arsenic trisulfide and triselenide

    International Nuclear Information System (INIS)

    Matkovskij, A.O.; Shvarts, K.K.; Pirogov, F.V.; Shpotyuk, O.I.; Savitskij, I.V.

    1988-01-01

    Peculiarities of photo-structural transformations and results of gamma- and electron-radiation effect upon microhardness, optical absorption, IK and EPR spectra have been studied for glassy chalcogenide semiconductors (GCS). It has been shown that high-energy-radiation-induced changes in the GCS physical properties depend on radiation parameters, thermal conditions and the composition of the sample. Mechanisms of radiation-induced transformations (RIC) for glassy arsenic trisulfide and triselenide are discussed. The RIC is supposed to have been predetermined by the following correlated processes: destruction-polymerization, radiation defect formation, and impurity radiolysis. 77 refs.; 10 figs.; 2 tabs

  5. Development of multifunctional fluoroelastomers based on nanocomposites; Desenvolvimento de elastomeros fluorados multifuncionais baseados em nanocompositos

    Energy Technology Data Exchange (ETDEWEB)

    Zen, Heloisa Augusto

    2015-07-01

    The fluoropolymers are known for their great mechanical properties, high thermal stability and resistance to aggressive chemical environment, and because of those properties they are widely used in industries, such as automobile, petroleum, chemistry, manufacturing, among others. To improve the thermal properties and gases barrier of the polymeric matrix, the incorporation of nanoparticle is used, this process permits the polymer to maintain their own characteristics and acquire new properties of nanoparticle. Because of those properties, the structural and morphological modification of fluoropolymers are very hard to be obtained through traditional techniques, in order to surmount this difficulty, the ionizing radiation is a well-known and effective method to modify fluoropolymers structures. In this thesis a nanocomposite polymeric based on fluoroelastomer (FKM) was developed and incorporated with four different configurations of nanoparticles: clay Cloisite 15A, POSS 1159, POSS 1160 and POSS 1163. After the nanocomposites films were obtained, a radiation induced grafting process was carried out, followed by sulfonation in order to obtain a ionic exchanged membrane. The effect of nanoparticle incorporation and the ionizing radiation onto films were characterized by X-ray diffraction, thermal and mechanical analysis, scanning electron microscopy and swelling; and the membranes were evaluated by degree of grafting, ionic exchange capacity and swelling. After the films were characterized, the crosslinking effect was observed to be predominant for the nanocomposites irradiated before the vulcanization, whereas the degradation was the predominant effect in the nanocomposites irradiated after vulcanization. (author)

  6. Development of multifunctional fluoroelastomers based on nanocomposites

    International Nuclear Information System (INIS)

    Zen, Heloisa Augusto

    2015-01-01

    The fluoropolymers are known for their great mechanical properties, high thermal stability and resistance to aggressive chemical environment, and because of those properties they are widely used in industries, such as automobile, petroleum, chemistry, manufacturing, among others. To improve the thermal properties and gases barrier of the polymeric matrix, the incorporation of nanoparticle is used, this process permits the polymer to maintain their own characteristics and acquire new properties of nanoparticle. Because of those properties, the structural and morphological modification of fluoropolymers are very hard to be obtained through traditional techniques, in order to surmount this difficulty, the ionizing radiation is a well-known and effective method to modify fluoropolymers structures. In this thesis a nanocomposite polymeric based on fluoroelastomer (FKM) was developed and incorporated with four different configurations of nanoparticles: clay Cloisite 15A, POSS 1159, POSS 1160 and POSS 1163. After the nanocomposites films were obtained, a radiation induced grafting process was carried out, followed by sulfonation in order to obtain a ionic exchanged membrane. The effect of nanoparticle incorporation and the ionizing radiation onto films were characterized by X-ray diffraction, thermal and mechanical analysis, scanning electron microscopy and swelling; and the membranes were evaluated by degree of grafting, ionic exchange capacity and swelling. After the films were characterized, the crosslinking effect was observed to be predominant for the nanocomposites irradiated before the vulcanization, whereas the degradation was the predominant effect in the nanocomposites irradiated after vulcanization. (author)

  7. Technological yields of sources for radiation processing

    International Nuclear Information System (INIS)

    Zagorski, Z.P.

    1993-01-01

    The present report is prepared for planners of radiation processing of any material. Calculations are focused on accelerators of electrons, divided into two groups: versatile linacs of energy up to 13 MeV, and accelerators of lower energy, below 2 MeV, of better energy yield but of limited applications. The calculations are connected with the confrontation of the author's technological expectations during the preparation of the linac project in the late '60s, with the results of 25 years of exploitation of the machine. One has to realize that from the 200 kW input power from the mains, only 5 kW of bent and scanned beam is recovered on the conveyor. That power is only partially used for radiation induced phenomena, because of the demanded homogeneity of the dose, of the mode of packing of the object and its shape, of edges of the scanned area and in the spaces between boxes, and of loses during the idle time due to the tuning of the machine and dosimetric operations. The use of lower energy accelerators may be more economical than that of linacs in case of objects of specific type. At the first stage already, that is of the conversion of electrical power into that of low energy electron beam, the yield is 2-3 times better than in the case of linacs. Attention has been paid to the technological aspects of electron beam conversion into the more penetrating Bremsstrahlung similar to gamma radiation. The advantages of technologies, which make possible a control of the shape of the processed object are stressed. Special attention is focused to the relation between the yield of processing and the ratio between the maximum to the minimum dose in the object under the irradiation. (author). 14 refs, 14 figs

  8. Induction-linear accelerators for food processing with ionizing radiation

    International Nuclear Information System (INIS)

    Lagunas-Solar, M.C.

    1985-01-01

    Electron accelerators with sufficient beam power and reliability of operation will be required for applications in the large-scale radiation processing of food. Electron beams can be converted to the more penetrating bremsstrahlung radiation (X-rays), although at a great expense in useful X-ray power due to small conversion efficiencies. Recent advances in the technology of pulse-power accelerators indicates that Linear Induction Electron Accelerators (LIEA) are capable of sufficiently high-beam current and pulse repetition rate, while delivering ultra-short pulses of high voltage. The application of LIEA systems in food irradiation provides the potential for high product output and compact, modular-type systems readily adaptable to food processing facilities. (orig.)

  9. Future of radiation processing of polymers

    International Nuclear Information System (INIS)

    Chapiro, A.; Tabata, Y.; Stannett, V.; Dole, M.; Dobo, J.; Charlesby, A.

    1990-01-01

    The present development of radiation processing in the polymer field including well established technologies, with large scale productions and substantial markets, such as: crosslinking; curing of monomer-polymer formulations; sterilization of plastic supplies; are discussed. The manufacture of sophisticated devices with low volume production but large added value: electronic devices; resistors and several promising applications for which only small commercial productions are on stream today: chain degradation; polymerization; graft copolymerization, are reviewed. (author)

  10. Pengaruh sulfur terhadap sifat fisika campuran pale crepe dan SBR untuk karet tahan panas

    Directory of Open Access Journals (Sweden)

    Arum Yuniari

    2013-12-01

    Full Text Available Sulfur plays an important role in the rubber vulcanization process especially in the formation of crosslinks. Heat resistant rubber made from mixing pale crepe and SBR requires the right amount of sulfur as crosslinking agent. The purpose of the study was to determine the effect of the addition of sulfur on the changes in physical properties before and after aging. Heat resistant rubber was made with variation of pale crepe/SBR: 80/20; 70/30; 60/40; 50/50 phr and sulfur variation of 1; 1.5 phr. The results showed that sulfur was influential in the crosslinks formation. The addition of 1 phr sulfur gave higher physical properties of the vulcanized with 1.5 phr sulfur. The changes of physical properties after aging process of the vulcanized with sulfur 1 phr was lower than the vulcanized with sulfur 1.5 phr. Vulcanized pale crepe/SBR (70/30 with 1 phr sulfur could be applied as heat-resistant rubber products.

  11. Radiative processes in a laser-fusion plasma

    International Nuclear Information System (INIS)

    Campbell, P.M.; Kubis, J.J.; Mitrovich, D.

    1976-01-01

    Plasmas compressed and heated by an intense laser pulse offer promise for the ignition of propagating thermonuclear burn and, ultimately, for use in fusion reactors. It is evident theoretically that the emission and absorption of x-rays by the plasma has a significant effect on the dynamics of the laser compression process. In order to achieve densities high enough for efficient thermonuclear burn, the fusion pellet must be compressed along a low adiabat. This will not be possible if the compressed region of the pellet is significantly preheated by x-rays originating in the hot outer regions. A satisfactory model of compression hydrodynamics must, therefore, include a comprehensive treatment of radiation transport based on a non-LTE model of the plasma. The model must be valid for Fermi-Dirac statistics, since high compression along a low adiabat will, in general, produce degenerate electron distributions. This report is concerned with the plasma model and the corresponding radiation emission and absorption coefficients, including nonthermal processes which occur in the laser deposition region

  12. Effect of Rubber Nanoparticle Agglomeration on Properties of Thermoplastic Vulcanizates during Dynamic Vulcanization

    Directory of Open Access Journals (Sweden)

    Hanguang Wu

    2016-04-01

    Full Text Available We previously reported that the dispersed rubber microparticles in ethylene-propylene-diene monomer (EPDM/polypropylene (PP thermoplastic vulcanizates (TPVs are actually agglomerates of rubber nanoparticles. In this study, based on this new understanding of the microstructure of TPV, we further revealed the microstructure-properties relationship of EPDM/PP TPV during dynamic vulcanization, especially the effect of the size of rubber nanoparticle agglomerates (dn, the thicknesses of PP ligaments (IDpoly and the rubber network on the properties of EPDM/PP TPV. We were able to simultaneously obtain a high tensile strength, elongation at break, elastic modulus, and elasticity for the EPDM/PP TPV by the achievement of a smaller dn, a thinner IDpoly and a denser rubber network. Interestingly, the effect of dn and IDpoly on the elastic modulus of EPDM/PP TPV composed of rubber nanoparticle agglomerates is different from that of EPDM/PP TPVs composed of rubber microparticles reported previously. The deformation behavior of the TPVs during stretching was studied to understand the mechanism for the achievement of good mechanical properties. Interestingly, the rubber nanoparticle agglomerates are oriented along the tensile direction during stretching. The TPV samples with smaller and more numerous rubber nanoparticle agglomerates can slow down the development of voids and cracks more effectively, thus leading to increase in tensile strength and elongation at break of the EPDM/PP TPV.

  13. The effect of low radiation doses on DNA repair processes

    International Nuclear Information System (INIS)

    Tuschl, H.

    1978-08-01

    Error free DNA repair processes are an important preprequisite for the maintenance of genetic integrity of cells. They are of special importance for persons therapeutically or occupationally exposed to radiation. Therefore the effect of radiation therapy and elevated natural background radiation on unscheduled DNA synthesis was tested in peripheral lymphocytes of exposed persons. Both, autoradiographic studies of unscheduled DNA synthesis and measurement of 3 H-thymidine uptake into double stranded and single-strand containing DNA fractions revealed an increase of capacity for DNA repair. (author)

  14. Role of activated carbon on micropollutans degradation by different radiation processes

    Directory of Open Access Journals (Sweden)

    Inmaculada Velo Gala

    2015-04-01

    Full Text Available The objective of this study was to analyse the influence of the presence of activated carbon on radiation processes. The triiodinated contrast medium diatrizoate was chosen as the contaminant model. We selected four commercial activated carbons and sixteen gamma radiation-modified carbons derived from these. The different advanced oxidation/reduction processes that have been studied were improved through the addition of activated carbon in the UV light and gamma radiating processes. In the UV/activated carbon process, the synergic activity of the activated carbon is enhanced in the samples with higher percentages of surface oxygen, ester/anhydride groups and carbon atoms with sp2 hybridization. Band gap determination of activated carbons revealed that they behave as semiconductor materials and, therefore, as photoactive materials in the presence of UV radiation, given that all band gap values are <4 eV. We also observed that the gamma radiation treatment reduces the band gap values of the activated carbons and that, in a single series of commercial carbons, lower band gap values correspond to higher contaminant removal rate values. We observed that the activity of the reutilized activated carbons is similar to that of the original carbons. Based on these results, we proposed that the activated carbon acts as a photocatalyst, promoting electrons of the valence band to the conduction band and increasing the generation of HO• radicals in the medium. Similarly, there was a synergic effect made by the presence of activated carbon in gamma radiation system, which favours pollutant removal. This synergic effect is independent of the textural but not the chemical characteristics of the activated carbon, observing a higher synergic activity for carbons with a higher surface content of oxygen, specifically quinone groups. We highlight that the synergic effect of the activated carbon requires adsorbent–adsorbate electrostatic interaction and is absent

  15. Radiation Processing of Advanced Composite Materials

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Phil Hyun; Jeun, Joonpyo; Nho, Young Chang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2008-04-15

    Advanced composites, such as carbon-fiber-reinforced plastics, are being used widely for many applications. Carbon fiber/epoxies composites have attracted special attention from the aircraft, aerospace, marine engineering, sporting goods and transportation industries, because they have useful mechanical properties including high strength-to-weight and stiffness-to-weight ratios, a corrosion resistant, impact and damage tolerance characteristics and wear properties. Thermal curing has been the dominant industrial process for advanced composites until now, however, a radiation curing process using UV, microwave x-ray, electron-beam(E-beam) and {gamma}-ray has emerged as a better alternative in recent years. These processes are compatible with the manufacturing of composites using traditional fabrication methods including a filament/tape winding, pultrusion, resin transfer moulding and hand lay-up. In this study, E-beam curable carbon fiber/epoxy composites were manufactured, and their mechanical properties were investigated. Two epoxy resins (bisphenol-A, bisphenol-F) containing photo-initiators (tri aryl sulfonium hexafluorophosphate, tri aryl sulfonium hexafluoroantimonate) were used as a matrix and a 4H-satin carbon woven fabric was used as a reinforcement. And then an electron beam irradiated the composites up to 200 kGy in a vacuum and an inert atmosphere. The cure cycle was optimized and the properties of composites were evaluated and analyzed via a differential scanning calorimetry, scanning electron microscopy, sol-gel extractions, FT-NIR, universal test machine, and an impact tester. The gel content, glass transition temperature and mechanical strength of the irradiated composites were increased with an increasing radiation dose.

  16. Optimization of industrial processes using radiation sources

    International Nuclear Information System (INIS)

    Salles, Claudio G.; Silva Filho, Edmundo D. da; Toribio, Norberto M.; Gandara, Leonardo A.

    1996-01-01

    Aiming the enhancement of the staff protection against radiation in operational areas, the SAMARCO Mineracao S.A. proceeded a reevaluation and analysis of the real necessity of the densimeters/radioactive sources in the operational area, and also the development of an alternative control process for measurement the ore pulp, and introduced of the advanced equipment for sample chemical analysis

  17. Proceedings of the Takasaki symposium on radiation processing of natural polymers

    International Nuclear Information System (INIS)

    Kume, Tamikazu; Maekawa, Yasunari

    2001-03-01

    This Takasaki symposium was held as enlargement of the Takasaki workshop on bilateral cooperations for radiation processing of natural polymers in 1999. The attendants were increased from 61 to 80 due to the expansion from five bilateral cooperation countries last year to further 3 Asian countries. At the symposium, the enhancement effects of plant growth and antifungal activity by radiation-degraded carbohydrates, hydrogels as a wound dressing material, and production of an protein free natural rubber grove were of major concern. Many domestic and foreign attendants were especially interested in novel functionality of radiation treated natural polymers and exchanged their opinions actively. Furthermore, since outstanding researchers in this field were invited from the Asian countries, we could also exchange the opinions about the present situation of the research activities interregional cooperation of the radiation processing in Asia. The 27 of the presented papers are indexed individually. (J.P.N.)

  18. Radiation processing technology for industrial waste water treatment

    International Nuclear Information System (INIS)

    2011-01-01

    Radiation sterilization technology, cross-linked polymers and curing, food and environmental applications of the radiation is widely used for many years. At the same time, drinking water and wastewater treatment are the part of the radiation technology applications. For this purpose, drinking water and wastewater treatment plants in various countries has been established. In this project, gamma / electron beam radiation treatment is intended to be used for the treatment of alkaloid, textiles and polychlorinated biphenyls (PCBs) wastewater. In this regard, the chemical characterization of wastewater, the interaction with radiation, biological treatment and determination of toxicological properties are the laboratory studies milestones. After laboratory studies, the establishment of a pilot scale treatment plant has been planned. Within the framework of the project a series of dye used in textile industry were examined. Besides the irradiation, the changes in treatment efficiency were investigated by using of oxygen and hydrogen peroxide in conjunction with the irradiation. Same working methods were implemented in the wastewater treatment of Bolvadin Opium Alkaloid Factory as well. In addition to chemical analysis in this study, aerobic and anaerobic biological treatment process also have been applied. Standard reference materials has been used for the marine sediment study contaminated with polychlorinated biphenyls.

  19. Radiation protection of workers in mining and processing of uranium ore

    International Nuclear Information System (INIS)

    Khan, A.H.; Sahoo, S.K; Puranik, V.D.

    2003-01-01

    Low grade of uranium ore mined from three underground mines is processed in a mill at Jaduguda in eastern India to recover uranium concentrate in the form of yellow cake. Radiation protection of workers is given due importance at all stages of these operations. Dedicated Health Physics Units and Environmental Survey Laboratories established at the site regularly carry out in-plant and environmental surveillance to keep radiation exposure of workers and the members of public within the limits prescribed by the regulatory body. The limits set by the national regulatory body based on the international standards recommended by the ICRP and the IAEA are followed. In the uranium mines, external gamma radiation, radon and airborne activity due to radioactive dust are monitored. Similarly, in the uranium ore processing mill, gamma radiation and airborne radioactivity due to long-lived α-emitters are monitored. Personal dosimeters are also issued to workers. The total radiation exposure of workers from external and internal sources is evaluated from the area and personal monitoring data. It has been observed that the average radiation dose to workers has been below 10 mSvy -1 and all exposures are well below 20 mSvy -1 at all stages of operations. Adequate ventilation is provided during mining and ore processing operations to keep the concentrations of airborne radioactivity well below the derived limits. Workers use personal protective appliances, where necessary, as a supplementary means of control. The monitoring methodologies, results and control measures are presented in the paper. (author)

  20. Dosimetric systems developed in Brazil for the radiation processes quality control

    International Nuclear Information System (INIS)

    Galante, Ana Maria Sisti; Campos, Leticia Lucente

    2011-01-01

    In order to apply new technologies to the industrial processing of materials aiming economy, efficiency, speed and high quality, ionizing radiation has been used in medicine, archaeology, chemistry, food preservation and other areas. For this reason, the dosimetry area looks for improve current dosimeters and develop new materials for application on quality control of these processes. In Brazil, the research in the dosimetry area occurs with great speed providing many different dosimetric systems. The chemical dosimetry is the most used technique in routine dosimetry, which requires fast and accurate responses. This technique involves determination of absorbed dose by measuring chemical changes radiation induced in the materials. Different dosimetric systems were developed at IPEN for application on radiation process quality and all of them present excellent results; the low cost of these materials allows a more effective dose control, therefore, a larger area or volume can be monitored. (author).

  1. Radiation processing for PTFE composite reinforced with carbon fiber

    International Nuclear Information System (INIS)

    Akihiro Oshima; Akira Udagawa; Yousuke Morita

    1999-01-01

    The present work is an attempt to evaluate the performance of crosslinked PTFE as a polymer matrix for carbon fiber-reinforced composite materials. The carbon fiber-reinforced PTFE pre-composite, which is laminated with PTFE fine powder, is crosslinked by electron beam irradiation. Mechanical and frictional properties of the crosslinked PTFE composite obtained are higher than those of PTFE resin. The crosslinked PTFE composite with high mechanical and radiation resistant performance is obtained by radiation crosslinking process

  2. Applications of Biopolymers Modified by Radiation Processing. Chapter 12

    Energy Technology Data Exchange (ETDEWEB)

    Tamada, M. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, Takasaki (Japan)

    2014-07-15

    Radiation processing using quantum beam such as electron beam and gamma rays is a clean process. Using this process, biopolymers with low environmental burden were modified for agricultural and environmental applications. High performance materials such as soil conditioner for arid area, spray coating Washi (Japanese paper), biodegradable dummy lens, chemically-induced biodegradable plastic, biodiesel catalyst, and plant growth promoter were developed by radiationinduced crosslinking, graft polymerization, and degradation. (author)

  3. Modeling of Cloud/Radiation Processes for Cirrus Cloud Formation

    National Research Council Canada - National Science Library

    Liou, K

    1997-01-01

    This technical report includes five reprints and pre-prints of papers associated with the modeling of cirrus cloud and radiation processes as well as remote sensing of cloud optical and microphysical...

  4. Radiation processing with high-energy X-rays

    International Nuclear Information System (INIS)

    Cleland, Marshall R.; Stichelbaut, Frederic

    2009-01-01

    The physical, chemical or biological characteristics of selected commercial products and materials can be improved by radiation processing. The ionizing energy can be provided by accelerated electrons with energies between 75 keV and 10 MeV, gamma rays from cobalt-60 with average energies of 1.25 MeV or X-rays with maximum energies up to 7.5 MeV. Electron beams are preferred for thin products, which are processed at high speeds. Gamma rays are used for products that are too thick for treatment with electron beams. High-energy X-rays can also be used for these purposes because their penetration in solid materials is similar to or even slightly greater than that of gamma rays. Previously, the use of X-rays had been inhibited by their slower processing rates and higher costs when compared with gamma rays. Since then, the price of cobalt-60 sources has been increased and the radiation intensity from high-energy, high-power X-ray generators has also increased. For facilities requiring at least 2 MCi of cobalt-60, the capital and operating costs of X-ray facilities with equivalent processing rates can be less than that of gamma-ray irradiators. Several high-energy electron beam facilities have been equipped with removable X-ray targets so that irradiation processes can be done with either type of ionizing energy. A new facility is now being built which will be used exclusively in the X-ray mode to sterilize medical products. Operation of this facility will show that high-energy, high-power X-ray generators are practical alternatives to large gamma-ray sources. (author)

  5. Standard Guide for Absorbed-Dose Mapping in Radiation Processing Facilities

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2003-01-01

    1.1 This document provides guidance in determining absorbed-dose distributions in products, materials or substances irradiated in gamma, X-ray (bremsstrahlung) and electron beam facilities. Note 1—For irradiation of food and the radiation sterilization of health care products, other specific ISO and ISO/ASTM standards containing dose mapping requirements exist. For food irradiation, see ISO/ASTM 51204, Practice for Dosimetry in Gamma Irradiation Facilities for Food Processing and ISO/ASTM 51431, Practice for Dosimetry in Electron and Bremsstrahlung Irradiation Facilities for Food Processing. For the radiation sterilization of health care products, see ISO 11137: 1995, Sterilization of Health Care Products Requirements for Validation and Routine Control Radiation Sterilization. In those areas covered by ISO 11137, that standard takes precedence. ISO/ASTM Practice 51608, ISO/ASTM Practice 51649, and ISO/ASTM Practice 51702 also contain dose mapping requirements. 1.2 Methods of analyzing the dose map data ar...

  6. Application of radiation in industrial processes (Paper No. IT-01)

    International Nuclear Information System (INIS)

    Murthy, T.S.

    1990-02-01

    The application of radiations both from gamma irradiation sources and electron beams has immense potential in diverse fields of industry and public health care programmes. The technical and economic effectiveness of radiation technology has been well demonstrated in different parts of the world and in India over last few years. The major applications for using this technology favourably considered all over the world include radiation sterilisation of medical products, hygienisation of sewage sludge, radiation processing of wood plastic composites, vulcanisation of natural rubber latex, cross linking of wires and cables using radiation, production of bio materials and drugs release systems and treatment of flue gases. Some of the areas which have been successfully exploited on an industrial or semi industrial scale in India and the current status of this programme is high lighted in this paper. (author). 9 refs

  7. Melt-processable, radiation cross-linkable E--CTFE copolymer compositions

    International Nuclear Information System (INIS)

    Robertson, A.B.; Schaffhauser, R.J.

    1976-01-01

    Melt-processable, radiation cross-linkable ethylene/chlorotrifluoroethylene copolymer compositions are provided which contain about 0.1 to 5 percent by weight of the copolymer of a radiation cross-linking promoter, about 0.01 to 5 percent by weight of an anti-oxidant and about 0.1 to 30 precent by weight of an acid scavenger. Such compositions do not give off odors when irradiated to cross-link the copolymer and do not develop bubbles after irradiation. 15 claims, no drawings

  8. Detection of radiation processing in onions

    International Nuclear Information System (INIS)

    Duchacek, V.

    1985-01-01

    Two breeds of onions were used for irradiation. Both breeds were divided into two parts - the first was irradiated with a dose of 80 Gy and the second served as a control. The two parts were stored under the same conditions. Conductometry, liquid chromatography and spectrophotometry were used for detecting the radiation processing of the onions. Only from the spectrophotometric determination of 2-desoxysaccharides it was possible to safely distinguish irradiated onions from non-irradiated controls throughout storage time. (E.S.)

  9. Guide for selection and calibration of dosimetry systems for radiation processing

    International Nuclear Information System (INIS)

    2002-01-01

    This guide covers the basis for selecting and calibrating dosimetry systems used to measure absorbed dose in gamma ray or X-ray fields and in electron beams used for radiation processing. It discusses the types of dosimetry systems that may be employed during calibration or on a routine basis as part of quality assurance in commercial radiation processing of products. This guide also discusses interpretation of absorbed dose and briefly outlines measurements of the uncertainties associated with the dosimetry. The details of the calibration of the analytical instrumentation are addressed in individual dosimetry system standard practices. The absorbed-dose range covered is up to 1 MGy (100 Mrad). Source energies covered are from 0.1 to 50 MeV photons and electrons. This guide should be used along with standard practices and guides for specific dosimetry systems and applications covered in other standards. Dosimetry for radiation processing with neutrons or heavy charged particles is not covered in this guide

  10. Genetic effects of ionizing radiation and repair processes

    International Nuclear Information System (INIS)

    Tuschl, H.

    1986-11-01

    Since DNA (=desoxyribonucleic acid) is the largest molecule within the cell it is the most important target for direct and indirect radiation effects. Within DNA the total genetic information is stored, thus damage to DNA in germ cells causes genetic disorders and damage in somatic cells is implicated in cancer and immunodeficiences. Alterations of DNA structure are not only due to ionizing radiation effects, but also to spontaneous DNA modifications and damage from interactions with environmental ultraviolet light and chemical agents. To maintain its genetic integrity, each organism had to develop different repair systems able to recognize and remove DNA damage. Repeated exposure to a DNA damaging agent can even lead to adaptation processes and increased resistance to the same agent. At normal function of repair systems it can be assumed that the capacity of those systems is adequate to scope with the effects of low radiation doses. (Author)

  11. Ionizing radiation processing and its potential in advancing biorefining and nanocellulose composite materials manufacturing.

    Science.gov (United States)

    Postek, Michael T; Poster, Dianne L; Vládar, András E; Driscoll, Mark S; LaVerne, Jay A; Tsinas, Zois; Al-Sheikhly, Mohamad I

    2018-02-01

    Nanocellulose is a high value material that has gained increasing attention because of its high strength, stiffness, unique photonic and piezoelectric properties, high stability and uniform structure. Through utilization of a biorefinery concept, nanocellulose can be produced in large volumes from wood at relatively low cost via ionizing radiation processing. Ionizing radiation causes significant break down of the polysaccharide and leads to the production of potentially useful gaseous products such as H 2 and CO. The application of radiation processing to the production of nanocellulose from woody and non-wood sources, such as field grasses, bio-refining byproducts, industrial pulp waste, and agricultural surplus materials remains an open field, ripe for innovation and application. Elucidating the mechanisms of the radiolytic decomposition of cellulose and the mass generation of nanocellulose by radiation processing is key to tapping into this source of nanocelluose for the growth of nanocellulostic-product development. More importantly, understanding the structural break-up of the cell walls as a function of radiation exposure is a key goal and only through careful, detailed characterization and dimensional metrology can this be achieved at the level of detail that is needed to further the growth of large scale radiation processing of plant materials. This work is resulting from strong collaborations between NIST and its academic partners who are pursuing the unique demonstration of applied ionizing radiation processing to plant materials as well as the development of manufacturing metrology for novel nanomaterials.

  12. Ionizing radiation processing and its potential in advancing biorefining and nanocellulose composite materials manufacturing

    Science.gov (United States)

    Postek, Michael T.; Poster, Dianne L.; Vládar, András E.; Driscoll, Mark S.; LaVerne, Jay A.; Tsinas, Zois; Al-Sheikhly, Mohamad I.

    2018-02-01

    Nanocellulose is a high value material that has gained increasing attention because of its high strength, stiffness, unique photonic and piezoelectric properties, high stability and uniform structure. Through utilization of a biorefinery concept, nanocellulose can be produced in large volumes from wood at relatively low cost via ionizing radiation processing. Ionizing radiation causes significant break down of the polysaccharide and leads to the production of potentially useful gaseous products such as H2 and CO. The application of radiation processing to the production of nanocellulose from woody and non-wood sources, such as field grasses, bio-refining by-products, industrial pulp waste, and agricultural surplus materials remains an open field, ripe for innovation and application. Elucidating the mechanisms of the radiolytic decomposition of cellulose and the mass generation of nanocellulose by radiation processing is key to tapping into this source of nanocelluose for the growth of nanocellulostic-product development. More importantly, understanding the structural break-up of the cell walls as a function of radiation exposure is a key goal and only through careful, detailed characterization and dimensional metrology can this be achieved at the level of detail that is needed to further the growth of large scale radiation processing of plant materials. This work is resulting from strong collaborations between NIST and its academic partners who are pursuing the unique demonstration of applied ionizing radiation processing to plant materials as well as the development of manufacturing metrology for novel nanomaterials.

  13. White matter and information processing speed following treatment with cranial-spinal radiation for pediatric brain tumor.

    Science.gov (United States)

    Scantlebury, Nadia; Bouffet, Eric; Laughlin, Suzanne; Strother, Douglas; McConnell, Dina; Hukin, Juliette; Fryer, Christopher; Laperriere, Normand; Montour-Proulx, Isabelle; Keene, Daniel; Fleming, Adam; Jabado, Nada; Liu, Fang; Riggs, Lily; Law, Nicole; Mabbott, Donald J

    2016-05-01

    We compared the structure of specific white matter tracts and information processing speed between children treated for posterior fossa tumors with cranial-spinal radiation (n = 30), or with surgery +/- focal radiation (n = 29), and healthy children (n = 37). Probabilistic diffusion tensor imaging (DTI) tractography was used to delineate the inferior longitudinal fasciculi, optic radiation, inferior frontal occipital fasciculi, and uncinate fasciculi bilaterally. Information processing speed was measured using the coding and symbol search subtests of the Wechsler Intelligence Scales, and visual matching, pair cancellation, and rapid picture naming subtests of the Woodcock-Johnson Test of Cognitive Ability, 3rd revision. We examined group differences using repeated measures MANOVAs and path analyses were used to test the relations between treatment, white matter structure of the tracts, and information processing speed. DTI indices of the optic radiations, the inferior longitudinal fasciculi, and the inferior fronto-occipital fasciculi differed between children treated with cranial-spinal radiation and children treated with surgery +/- focal radiation, and healthy controls (p = .045). Children treated with cranial-spinal radiation also exhibited lower processing speed scores relative to healthy control subjects (p = .002). Notably, we observed that group differences in information processing speed were related to the structure of the right optic radiation (p = .002). We show that cranial-spinal radiation may have a negative impact on information processing speed via insult to the right optic radiations. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  14. Food packaging materials and radiation processing of food: a brief review

    International Nuclear Information System (INIS)

    Chuaqui-Offermanns, N.

    1989-01-01

    Food is usually packaged to prevent microbial contamination and spoilage. Ionizing radiation can be applied to food-packaging materials in two ways: (i) sterilization of packaging materials for aseptic packaging, and (ii) radiation processing of prepackaged food. In aseptic packaging, a sterile package is filled with a sterile product in a microbiologically controlled environment. In irradiation of prepackaged food, the food and the packaging material are irradiated simultaneously. For both applications, the radiation stability of the packaging material is a key consideration if the technology is to be used successfully. To demonstrate the radiation stability of the packaging material, it must be shown that irradiation does not significantly alter the physical and chemical properties of the material. The irradiated material must protect the food from environmental contamination while maintaining its organoleptic and toxicological properties. Single-layer plastics cannot meet the requirements of either application. Multilayered structures produced by coextrusion would likely satisfy the demands of radiation processing prepackaged food. In aseptic packaging, the package is irradiated prior to filling, making demands on toxicological safety less stringent. Therefore, multilayered structures produced by coextrusion, lamination or co-injection moulding could satisfy the requirements. (author)

  15. Guidelines for the Development, Validation and Routine Control of Industrial Radiation Processes

    DEFF Research Database (Denmark)

    Safrany, A.; Miller, Arne; Kovacs, A.

    Radiation processing has become a well accepted technology on the global market, with uses ranging from the sterilization of medical devices to polymer cross-linking and curing to the irradiation of selected food items. Besides these well established uses, new radiation technology applications...... are emerging for environmental remediation and the synthesis of advanced materials and products. Quality assurance is vital for the success of these technologies and requires the development of standardized procedures as well as the harmonization of process validation and process control. It is recognized...

  16. Tungsten Ions in Plasmas: Statistical Theory of Radiative-Collisional Processes

    Directory of Open Access Journals (Sweden)

    Alexander V. Demura

    2015-05-01

    Full Text Available The statistical model for calculations of the collisional-radiative processes in plasmas with tungsten impurity was developed. The electron structure of tungsten multielectron ions is considered in terms of both the Thomas-Fermi model and the Brandt-Lundquist model of collective oscillations of atomic electron density. The excitation or ionization of atomic electrons by plasma electron impacts are represented as photo-processes under the action of flux of equivalent photons introduced by E. Fermi. The total electron impact single ionization cross-sections of ions Wk+ with respective rates have been calculated and compared with the available experimental and modeling data (e.g., CADW. Plasma radiative losses on tungsten impurity were also calculated in a wide range of electron temperatures 1 eV–20 keV. The numerical code TFATOM was developed for calculations of radiative-collisional processes involving tungsten ions. The needed computational resources for TFATOM code are orders of magnitudes less than for the other conventional numerical codes. The transition from corona to Boltzmann limit was investigated in detail. The results of statistical approach have been tested by comparison with the vast experimental and conventional code data for a set of ions Wk+. It is shown that the universal statistical model accuracy for the ionization cross-sections and radiation losses is within the data scattering of significantly more complex quantum numerical codes, using different approximations for the calculation of atomic structure and the electronic cross-sections.

  17. Radiation processing of food: a promising technology to ensure food safety and security

    International Nuclear Information System (INIS)

    Gautam, S.

    2016-01-01

    Radiation processing of food involves controlled application of energy from ionizing radiations. Approved sources of radiation for food processing are radioisotopes (Cobalt-60 and Caesium-137), electron beam (up to 10 MeV) and X-rays (up to 5 MeV). Radiation processing of food is carried out in an irradiation chamber shielded by 1.5 - 1.8 m thick concrete walls. Food, either pre-packed or in-bulk, placed in suitable containers is sent into the irradiation chamber with the help of an automatic conveyor. Major benefits achieved by radiation processing of food are: (i) inhibition of sprouting of tubers and bulbs; (ii) disinfestations of insect pests in agricultural commodities; (iii) delay in ripening and senescence of fruits and vegetables; (iv) destruction of microbes responsible for spoilage, and (v) elimination of pathogens and parasites of public health importance. Irradiation produces very little chemical changes in food. The majority of changes are similar to those by other preservation methods like heat. The radiolytic products and free radicals produced are identical to those present in foods subjected to treatment such as cooking and canning. None of the changes known to occur have been found to be harmful. Twelve food irradiation plants have been commissioned till date in the private sector in India. Two plants set by Government of India (Radiation Processing Plant, Vashi, Navi Mumbai; and KRUSHAK, Lasalgaon, Nashik) are also operational. Volume of food irradiated in India has been steadily increasing. Recent development in the area of food irradiation in India include harmonization of food irradiation rules with international regulation

  18. Radiation processing program at the Malaysian Nuclear Agency

    International Nuclear Information System (INIS)

    Khairul Zaman

    2007-01-01

    Radiation processing technology has been proven to enhance industrial efficiency and productivity, improve product quality and competitiveness. For many years, variety of radiation crosslinkable materials based on synthetic polymers have been studied at the Malaysian Nuclear Agency either in the form of thermoplastic resins, polymer blends or composites. At present, effort is focused towards developing new materials based on natural polymers such as natural rubber and rubber based products, palm oil and palm oil based products and polysaccharide. In this respect, the most challenging issues are to develop new materials/products that have commercial value and to bring the products from laboratory to market. (author)

  19. Heat pump processes induced by laser radiation

    Science.gov (United States)

    Garbuny, M.; Henningsen, T.

    1980-01-01

    A carbon dioxide laser system was constructed for the demonstration of heat pump processes induced by laser radiation. The system consisted of a frequency doubling stage, a gas reaction cell with its vacuum and high purity gas supply system, and provisions to measure the temperature changes by pressure, or alternatively, by density changes. The theoretical considerations for the choice of designs and components are dicussed.

  20. A comparison between the effects of gamma radiation and sulfur cure system on the microstructure and crosslink network of (styrene butadiene rubber/ethylene propylene diene monomer) blends in presence of nanoclay

    Science.gov (United States)

    Shoushtari Zadeh Naseri, Aida; Jalali-Arani, Azam

    2015-10-01

    Rubber blends based on (styrene-butadiene rubber (SBR)/ethylene-propylene-diene monomer (EPDM)) with and without organoclay (OC) were prepared through a melt mixing process. The concentration ratio of the rubber phases (EPDM/SBR; 50/50 wt%) and the amount of the OC were kept constant. The samples were then vulcanized by means of gamma radiation using a Co-60 gamma source as well as sulfur cure system. The effect of absorbed dose on the formation of the crosslinks was confirmed by the Fourier transform infrared spectroscopy (FTIR). The effects of absorbed dose, sulfur cure system and OC on the gel content, and crosslink density were evaluated by the chemical tests. Applying the Charlesby-Pinner equation to estimate the radiation chemical yield, revealed that the use of OC in the blend caused 20% reduction in the degradation/crosslinking ratio. Employing the swelling test data, some thermodynamic parameters were determined. Using field emission scanning electron microscopy (FE-SEM) to investigate microstructure of the samples revealed a more homogeneous structure and also an increase in compatibility of the blend components in the sample cured by the irradiation in comparison to that cured by the sulfur curing system.

  1. Sensorial analysis evaluation in cereal bars preserved by ionizing radiation processing

    International Nuclear Information System (INIS)

    Villavicencio, A.L.C.H.; Araujo, M.M.; Fanaro, G.B.; Rela, P.R.; Mancini-Filho, J.

    2007-01-01

    Gamma-rays utilized as a food-processing treatment to eliminate insect contamination is well established in food industries. Recent troubles in Brazilian cereal bars commercialization require a special consumer's attention because some products were contaminated by insects. To solve the problem, food-irradiation treatment was utilized as a safe and effective solution. The final product was free of insect contamination. The aim of this study was to determine the best radiation dose processing utilized to disinfestations and detect some change on sensorial characteristic by sensorial analysis in cereal bars. In this study, three different kinds of cereal bars were purchased in Sao Paulo (Brazil) in supermarkets and irradiated with 1.0, 2.0 and 3.0 kGy at 'Instituto de Pesquisas Energeticas e Nucleares' (IPEN-CNEN/SP). The samples were treated with ionizing radiation using a 60 Co gamma-ray facility (Gammacell 220, A.E.C.L.). That radiation doses were used successfully as an anti-insect treatment in the cereal bars, since in some food industries doses up to 3.0 kGy are used to guarantee at least a dose of 1.0 kGy in internal cereal bars package. Sensorial analysis was necessary since cereal bars contain ingredients very sensitive to ionizing radiation process

  2. The application of radiation technology in industrial processes: current and future perspectives

    International Nuclear Information System (INIS)

    Silverman, J.

    1975-01-01

    The development of nuclear power has been responsible for many by-products, among them radioactive fission products. In the late 1940's and early 1950's considerable efforts were made to develop industrial processes that could make use of the fission products in large quantities. Although some fission products are utilized today, the scale does not approach the quantities that will be produced in a nuclear economy. The efforts have not been a failure, however, and the research to develop industrial processes has created markets, not for the fission products as one had hoped, but for the radioisotope Cobalt-60 produced by neutron capture in a nuclear reactor, and for accelerators - machines that produce radiation in a controlled manner. Success in finding uses for the major fission products may yet come, as research continues in the radiation chemistry and radiation biology fields. Radiation processing is now a vigorously expanding area because of sharp increases in the reliability of electron beam generators, sharp drops in the unit cost of both electron beam power and electron beam energy, significant advances in radiation chemistry leading to lower dose requirements and increased engineering knowledge and practical experience. he principal reasons for its bright future promise arise from expectations of further sharp decreases in the unit cost of electron beam energy and from the recent successful adoption of radiation on a large scale for cross linking of telephone wire insulation in the United States. (author)

  3. Electronic data processing in radiation protection: what could, what should it achieve today?

    International Nuclear Information System (INIS)

    Witt, H. de; Frasch, G.; Kragh, P.; Wirth, E.; Graffunder, H.; Heck, B.; Hill, P.; Wuest, E.; Leeb, H.

    1998-01-01

    Benefits and Risks of the use of Electronic Data Processing in Radiation Protection are evaluated. Numerous examples are given for the application of computers and programs for assessment, processing, administration and presentation of radiation protection relevant measurement data. This includes the possibilities for obtaining information and exchanging data and experiences via internet. (orig.) [de

  4. Mechanical and Electrical Properties of Sulfur-Containing Polymeric Materials Prepared via Inverse Vulcanization

    Directory of Open Access Journals (Sweden)

    Sergej Diez

    2017-02-01

    Full Text Available Recently, new methods have been developed for the utilization of elemental sulfur as a feedstock for novel polymeric materials. One promising method is the inverse vulcanization, which is used to prepare polymeric structures derived from sulfur and divinyl comonomers. However, the mechanical and electrical properties of the products are virtually unexplored. Hence, in the present study, we synthesized a 200 g scale of amorphous, hydrophobic as well as translucent, hyperbranched polymeric sulfur networks that provide a high thermal resistance (>220 °C. The polymeric material properties of these sulfur copolymers can be controlled significantly by varying the monomers as well as the feed content. The investigated comonomers are divinylbenzene (DVB and 1,3-diisopropenylbenzene (DIB. Plastomers with low elastic content and high shape retention containing 12.5%–30% DVB as well as low viscose waxy plastomers with a high flow behavior containing a high DVB content of 30%–35% were obtained. Copolymers with 15%–30% DIB act, on the one hand, as thermoplastics and, on the other hand, as vitreous thermosets with a DIB of 30%–35%. Results of the thermogravimetric analysis (TGA, the dynamic scanning calorimetry (DSC and mechanical characterization, such as stress–strain experiments and dynamic mechanical thermal analysis, are discussed with the outcome that they support the assumption of a polymeric cross-linked network structure in the form of hyper-branched polymers.

  5. Reactor similarity for plasma–material interactions in scaled-down tokamaks as the basis for the Vulcan conceptual design

    International Nuclear Information System (INIS)

    Whyte, D.G.; Olynyk, G.M.; Barnard, H.S.; Bonoli, P.T.; Bromberg, L.; Garrett, M.L.; Haakonsen, C.B.; Hartwig, Z.S.; Mumgaard, R.T.; Podpaly, Y.A.

    2012-01-01

    Highlights: ► Discussion of similarity scalings for reduced-size tokamaks. ► Proposal of a new set of scaling laws for divertor similarity. ► Discussion of how the new scaling provides fidelity to a reactor. ► The new scaling is used as the basis for the Vulcan conceptual design. - Abstract: Dimensionless parameter scaling techniques are a powerful tool in the study of complex physical systems, especially in tokamak fusion experiments where the cost of full-size devices is high. It is proposed that dimensionless similarity be used to study in a small-scale device the coupled issues of the scrape-off layer (SOL) plasma, plasma–material interactions (PMI), and the plasma-facing material (PFM) response expected in a tokamak fusion reactor. Complete similarity is not possible in a reduced-size device. In addition, “hard” technological limits on the achievable magnetic field and peak heat flux, as well as the necessity to produce non-inductive scenarios, must be taken into account. A practical approach is advocated, in which the most important dimensionless parameters are matched to a reactor in the reduced-size device, while relaxing those parameters which are far from a threshold in behavior. “Hard” technological limits are avoided, so that the reduced-size device is technologically feasible. A criticism on these grounds is offered of the “P/R” model, in which the ratio of power crossing the last closed flux surface (LCFS), P, to the device major radius, R, is held constant. A new set of scaling rules, referred to as the “P/S” scaling (where S is the LCFS area) or the “PMI” scaling, is proposed: (i) non-inductive, steady-state operation; (ii) P is scaled with R 2 so that LCFS areal power flux P/S is constant; (iii) magnetic field B constant; (iv) geometry (elongation, safety factor q * , etc.) constant; (v) volume-averaged core density scaled as n≈n ¯ e ∼R −2/7 ; and (vi) ambient wall material temperature T W,0 constant. It is

  6. Radiation Processed Materials in Products from Polymers for Agricultural Applications

    International Nuclear Information System (INIS)

    2014-07-01

    This publication results from a technical meeting on radiation processed materials in products from polymers for agricultural applications, which was held from 8 to 12 July 2013 at the IAEA in Vienna. The meeting provided a forum for the sharing of practical experiences and lessons learned, and reviewed the recent developments in the use of radiation technologies for the preparation of environmental friendly products based on polymers for agricultural applications

  7. Radiation Processed Materials in Products from Polymers for Agricultural Applications

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-15

    This publication results from a technical meeting on radiation processed materials in products from polymers for agricultural applications, which was held from 8 to 12 July 2013 at the IAEA in Vienna. The meeting provided a forum for the sharing of practical experiences and lessons learned, and reviewed the recent developments in the use of radiation technologies for the preparation of environmental friendly products based on polymers for agricultural applications.

  8. Consenting process for radiation facilities. V. 4

    International Nuclear Information System (INIS)

    2011-03-01

    Safety codes and standards are formulated on the basis of nationally and internationally accepted safety criteria for design, construction and operation of specific equipment, systems, structures and components of nuclear and radiation facilities. Safety, codes establish the objectives and set requirements that shall be fulfilled to provide adequate assurance for safety. Safety codes establish the objectives and set requirements that shall be fulfilled to provide adequate assurance for safety. Safety guides elaborate various requirements and furnish approaches for their implementation. Safety manuals deal with specific topics and contain detailed scientific and technical information on the subject. These documents are prepared by experts in the relevant fields and are extensively reviewed by advisory committees of the Atomic Energy Regulatory Board (AERB) before they are published. The documents are revised when necessary, in the light of experience and feedback from users as well as new developments in the field. AERB issued a safety code on Regulation of Nuclear and Radiation Facilities (AERB/SC/G) to spell out the requirements/obligations to be met by a nuclear or radiation facility for the issue of regulatory consent at every stage. This safety guide apprises the details of the regulatory requirements for setting up the radiation facility such as consenting process, the stages requiring consent, wherever applicable documents to be submitted and the nature and extent of review. The guide also gives information on methods of review and assessment adopted by AERB

  9. Consenting process for radiation facilities. V. 3

    International Nuclear Information System (INIS)

    2011-03-01

    Safety codes and standards are formulated on the basis of nationally and internationally accepted safety criteria for design, construction and operation of specific equipment, systems, structures and components of nuclear and radiation facilities. Safety, codes establish the objectives and set requirements that shall be fulfilled to provide adequate assurance for safety. Safety codes establish the objectives and set requirements that shall be fulfilled to provide adequate assurance for safety. Safety guides elaborate various requirements and furnish approaches for their implementation. Safety manuals deal with specific topics and contain detailed scientific and technical information on the subject. These documents are prepared by experts in the relevant fields and are extensively reviewed by advisory committees of the Atomic Energy Regulatory Board (AERB) before they are published. The documents are revised when necessary, in the light of experience and feedback from users as well as new developments in the field. AERB issued a safety code on Regulation of Nuclear and Radiation Facilities (AERB/SC/G) to spell out the requirements/obligations to be met by a nuclear or radiation facility for the issue of regulatory consent at every stage. This safety guide apprises the details of the regulatory requirements for setting up the radiation facility such as consenting process, the stages requiring consent, wherever applicable documents to be submitted and the nature and extent of review. The guide also gives information on methods of review and assessment adopted by AERB

  10. Consenting process for radiation facilities. V. 1

    International Nuclear Information System (INIS)

    2011-03-01

    Safety codes and standards are formulated on the basis of nationally and internationally accepted safety criteria for design, construction and operation of specific equipment, systems, structures and components of nuclear and radiation facilities. Safety, codes establish the objectives and set requirements that shall be fulfilled to provide adequate assurance for safety. Safety codes establish the objectives and set requirements that shall be fulfilled to provide adequate assurance for safety. Safety guides elaborate various requirements and furnish approaches for their implementation. Safety manuals deal with specific topics and contain detailed scientific and technical information on the subject. These documents are prepared by experts in the relevant fields and are extensively reviewed by advisory committees of the Atomic Energy Regulatory Board (AERB) before they are published. The documents are revised when necessary, in the light of experience and feedback from users as well as new developments in the field. AERB issued a safety code on Regulation of Nuclear and Radiation Facilities (AERB/SC/G) to spell out the requirements/obligations to be met by a nuclear or radiation facility for the issue of regulatory consent at every stage. This safety guide apprises the details of the regulatory requirements for setting up the radiation facility such as consenting process, the stages requiring consent, wherever applicable documents to be submitted and the nature and extent of review. The guide also gives information on methods of review and assessment adopted by AERB

  11. A review on the status and future trends of radiation processing in Iran

    Directory of Open Access Journals (Sweden)

    S.R. Rafiee

    2017-10-01

    Full Text Available A comprehensive review on the status of radiation processing and its future in Iran is presented since 32 years ago up to now to show the development of Iran's irradiation industry. Additionally, annual throughput of treated materials with their types and names are also given and also all of the radiation facilities both in service and under construction as well as the plans and estimations for establishing the new facilities are outlined. Our investigations show that the trend of radiation processing industry in Iran is growing rapidly.

  12. Prospects for the application of radioisotopes and radiation and activities of the IAEA

    International Nuclear Information System (INIS)

    Machi, Sueo

    1996-01-01

    The applications of nuclear techniques for human health, food and agriculture, environmental protection, industry have been increasing. 'Food for all' was the spirit of the Declaration of the World Food Summit 1996 in Rome. Nuclear techniques have proven to be extremely useful to improve the productivity of agriculture. The IAEA has been successful in developing better varieties of banana, barley, sorghum and cassava in the past 5 years by mutation breeding, combined with tissue culture. The sterile insect technique (SIT) has been successfully used to eradicate insect pests. Chile declared this year the eradication of the medfly. The new world screwworm in Libya was eradicated in 1992 by the joint efforts of FAO and IAEA. Eradication of the tsetse fly in Tanzania is an IAEA Model Project to be achieved by the end of 1997. The IAEA's priority activities in radiotherapy are training radiotherapists, quality assurance for therapy and developing low cost and simpler therapy equipment. The applications of radioimmunoassay for screening neonatal hypothyroidism are successfully being used in Tunisia, Uruguay, Costa Rica, Colombia, Thailand. The tissue bank project which involves radiation sterilization is being implemented in RCA countries. The cleaning of flue gases from coal burning power stations is being studied in Japan, Poland, Germany, Brazil, the Republic of Korea, China. The IAEA is implementing a project in Poland on an industrial scale demonstration plant. In Bulgaria a pilot plant to clean flue gases with a high SO2 content will be constructed in 1997-1998. Industrial applications of radiation processing are growing in upgrading polymeric material, curing of surface coating and irradiation of medical products. Radiation vulcanization of natural rubber latex is an excellent achievement of the IAEA/RCA project with Malaysia. (J.P.N.)

  13. Prospects for the application of radioisotopes and radiation and activities of the IAEA

    Energy Technology Data Exchange (ETDEWEB)

    Machi, Sueo [International Atomic Energy Agency, Vienna (Austria). Dept. of Research and Isotopes

    1996-12-31

    The applications of nuclear techniques for human health, food and agriculture, environmental protection, industry have been increasing. `Food for all` was the spirit of the Declaration of the World Food Summit 1996 in Rome. Nuclear techniques have proven to be extremely useful to improve the productivity of agriculture. The IAEA has been successful in developing better varieties of banana, barley, sorghum and cassava in the past 5 years by mutation breeding, combined with tissue culture. The sterile insect technique (SIT) has been successfully used to eradicate insect pests. Chile declared this year the eradication of the medfly. The new world screwworm in Libya was eradicated in 1992 by the joint efforts of FAO and IAEA. Eradication of the tsetse fly in Tanzania is an IAEA Model Project to be achieved by the end of 1997. The IAEA`s priority activities in radiotherapy are training radiotherapists, quality assurance for therapy and developing low cost and simpler therapy equipment. The applications of radioimmunoassay for screening neonatal hypothyroidism are successfully being used in Tunisia, Uruguay, Costa Rica, Colombia, Thailand. The tissue bank project which involves radiation sterilization is being implemented in RCA countries. The cleaning of flue gases from coal burning power stations is being studied in Japan, Poland, Germany, Brazil, the Republic of Korea, China. The IAEA is implementing a project in Poland on an industrial scale demonstration plant. In Bulgaria a pilot plant to clean flue gases with a high SO2 content will be constructed in 1997-1998. Industrial applications of radiation processing are growing in upgrading polymeric material, curing of surface coating and irradiation of medical products. Radiation vulcanization of natural rubber latex is an excellent achievement of the IAEA/RCA project with Malaysia. (J.P.N.)

  14. Process for curing ionizing radiation-highly sensitive resin composition

    International Nuclear Information System (INIS)

    Araki, K.; Sasaki, T.; Tabei, K.; Goto, K.

    1979-01-01

    A process is described for curing a radiation curable composition consisting essentially of (a) an amide represented by the formula R,CONR 2 R 3 and (b) an unsaturated polyester resin by irradiating the composition with an ionizing radiation. R 1 is H, an alkyl groups having from 1 to 17 carbon atoms or an alkenyl groups having from 1 to 17 carbon atoms, and R 2 and R 3 are each -H, -CH 3 , or -CH 2 OH. R 1 and R 2 taken together represent alkylene having 2 to 5 carbon atoms

  15. ESR and microbiological studies on gamma radiation processed dehydrated onion powder

    International Nuclear Information System (INIS)

    Khedkar, K.C.; Kumbhare, M.N.; Sharma, G.; Lavale, D.S.; Kadam, R.M.; Bhide, M.K.; Sastry, M.D.

    2001-01-01

    Paper describes the potential of ESR technique for detection of free radicals produced in the irradiated onion powder. Experiments were carried out to evaluate the effect of light, moisture and time on the stability of free radicals produced by gamma radiation. Some microbiological studies were also carried out on unprocessed and radiation-processed product. (author)

  16. Radiation Processing of Natural Polymers for Industrial Applications

    International Nuclear Information System (INIS)

    Hegazy, E.A.

    2008-01-01

    Radiation induced degradation technology is a new and promising application of ionizing radiation to develop viscose, pulp, paper, food preservation, pharmaceutical production, and natural bioactive agents industries. Controlling the degree of degradation, uniform molecular weight distribution, saving achieved in the chemicals (used in conventional methods) on a cost basis, and environmentally friendly process are the beneficial effects of using radiation technology in these industries. However, for some development countries such technology is not economic. Therefore, a great effort should be done to reduce the cost required for such technologies. One of the principle factors for reducing the cost is achieving the degradation at low irradiation doses. The addition of some additives such as potassium per-sulfate (KPS), ammonium per-sulfate (APS), or H 2 O 2 to natural polymers (carboxy-methylcellulose (CMC), chitosan, carrageenan and Na-alginate) during irradiation process accelerates their degradation. The highest degradation rate of polysaccharides obtained when APS was used. The end product of irradiated CMC, chitosan, carrageenan and Na-alginate may be used as food additive or benefited in agricultural purposes. On the other hand, radiation crosslinking of PAAm or PNIPAAm is affected by the presence of natural polymer like CMC-Na and carrageenan due to their degradability which could be controlled according to its concentration in the bulk medium and irradiation dose. Accordingly, the gel content, thermo-sensitivity (LCST) and swelling properties of PNIPAAm based natural polymers could be controlled. The swelling of the prepared copolymer hydrogels was investigated for its possible use in personal care articles particularly diapers or as carriers for drug delivery systems. The prepared crosslinked copolymers possessed high and fast swelling properties in simulated urine media and the swelling ratios of CMC-Na /PAAm gels in urine are acceptable for diaper

  17. Dosimetry systems for radiation processing in Japan

    International Nuclear Information System (INIS)

    Tamura, Naoyuki

    1995-01-01

    The present situation of dosimetry systems for radiation processing industry in Japan is reviewed. For gamma-rays irradiation the parallel-plate ionization chamber in TRCRE, JAERI has been placed as a reference standard dosimeter for processing-level dose. Various solid and liquid chemical dosimeters are used as routine dosimeters for gamma processing industries. Alanine dosimeters is used for the irradiation purpose which needs precise dosimetry. For electron-beam irradiation the electron current density meter and the total absorption calorimeter of TRCRE are used for the calibration of routine dosimeters. Plastic film dosimeters, such as cellulose triacetate and radiochromic dye are used as routine dosimeters for electron processing industries. When the official traceability systems for processing-level dosimetry now under investigation is completed, the ionization chamber of TRCRE is expected to have a role of the primary standard dosimeter and the specified alanine dosimeter will be nominated for the secondary or reference standard dosimeter. (author)

  18. Image processing techniques for thermal, x-rays and nuclear radiations

    International Nuclear Information System (INIS)

    Chadda, V.K.

    1998-01-01

    The paper describes image acquisition techniques for the non-visible range of electromagnetic spectrum especially thermal, x-rays and nuclear radiations. Thermal imaging systems are valuable tools used for applications ranging from PCB inspection, hot spot studies, fire identification, satellite imaging to defense applications. Penetrating radiations like x-rays and gamma rays are used in NDT, baggage inspection, CAT scan, cardiology, radiography, nuclear medicine etc. Neutron radiography compliments conventional x-rays and gamma radiography. For these applications, image processing and computed tomography are employed for 2-D and 3-D image interpretation respectively. The paper also covers main features of image processing systems for quantitative evaluation of gray level and binary images. (author)

  19. Evaluation of peach palm (Bactris gasipaes Kunth) processed by radiation

    International Nuclear Information System (INIS)

    Silva, Priscila Vieira da

    2009-01-01

    The peach palm can be obtained from several species of palms, but the peach palm has attracted great interest by producers, as has characteristics of precocity, rusticity and tillering, producing a palm-quality differentiating it from other palmettos for their sweet flavor and yellowish . The food irradiation has been used as a treatment to ensure microbiological food safety of products to avoid infection. Its use combined with minimal processing could increase the safety and quality of minimally processed vegetables. We aimed at evaluating the effect of gamma radiation and electron beams to control bacteria; assess the physical characteristics through analysis of color and texture in peach palm in natura minimally processed and subjected to ionizing radiation stored at 8 deg C as well as evaluating the sensory characteristics. The results in the microbiological analysis showed that ionizing radiation promotes reduction of microbial load in both treatments. In the analysis of color we can conclude that among all the treatments the sample irradiated with 1.5 kGy showed more differences when compared with the other samples. Observing texture characteristics we could conclude that irradiation changed the texture of the palm, unlike the treatment by electron beams that showed no difference between samples. For the sensory analysis, the gamma radiation with dose of 1.5 kGy, induced changes in sensory properties to the attributes and overall appearance. The dose of 1 kGy caused no significant difference, so a recommended dose for the irradiation of the studied product. (author)

  20. Development of FPGA-based digital signal processing system for radiation spectroscopy

    International Nuclear Information System (INIS)

    Lee, Pil Soo; Lee, Chun Sik; Lee, Ju Hahn

    2013-01-01

    We have developed an FPGA-based digital signal processing system that performs both online digital signal filtering and pulse-shape analysis for both particle and gamma-ray spectroscopy. Such functionalities were made possible by a state-of-the-art programmable logic device and system architectures employed. The system performance as measured, for example, in the system dead time and accuracy for pulse-height and rise-time determination, was evaluated with standard alpha- and gamma-ray sources using a CsI(Tl) scintillation detector. It is resulted that the present system has shown its potential application to various radiation-related fields such as particle identification, radiography, and radiation imaging. - Highlights: ► An FPGA-based digital processing system was developed for radiation spectroscopy. ► Our digital system has a 14-bit resolution and a 100-MHz sampling rate. ► The FPGA implements the online digital filtering and pulse-shape analysis. ► The pileup rejection is implemented in trigger logic before digital filtering process. ► Our digital system was verified in alpha-gamma measurements using a CsI detector

  1. Economic assessment of possible electron accelerator applications in curing silicon rubber based electric installation material

    International Nuclear Information System (INIS)

    Rmot, L.

    1976-01-01

    A description is given of the conventional technology of production of conductors with silicon rubber insulation and of the radiation vulcanization method, i.e., the radiation cross-linking of silicon rubber. An economic comparison is shown for both technologies. The analysis shows that the indices for the radiation cross-linking technology are favourable and that the introduction thereof would be advantageous. (J.P.)

  2. Developing Quality Assurance Processes for Image-Guided Adaptive Radiation Therapy

    International Nuclear Information System (INIS)

    Yan Di

    2008-01-01

    Quality assurance has long been implemented in radiation treatment as systematic actions necessary to provide adequate confidence that the radiation oncology service will satisfy the given requirements for quality care. The existing reports from the American Association of Physicists in Medicine Task Groups 40 and 53 have provided highly detailed QA guidelines for conventional radiotherapy and treatment planning. However, advanced treatment processes recently developed with emerging high technology have introduced new QA requirements that have not been addressed previously in the conventional QA program. Therefore, it is necessary to expand the existing QA guidelines to also include new considerations. Image-guided adaptive radiation therapy (IGART) is a closed-loop treatment process that is designed to include the individual treatment information, such as patient-specific anatomic variation and delivered dose assessed during the therapy course in treatment evaluation and planning optimization. Clinical implementation of IGART requires high levels of automation in image acquisition, registration, segmentation, treatment dose construction, and adaptive planning optimization, which brings new challenges to the conventional QA program. In this article, clinical QA procedures for IGART are outlined. The discussion focuses on the dynamic or four-dimensional aspects of the IGART process, avoiding overlap with conventional QA guidelines

  3. Radiation-resistant requirements analysis of device and control component for advanced spent fuel management process

    Energy Technology Data Exchange (ETDEWEB)

    Song, Tai Gil; Park, G. Y.; Kim, S. Y.; Lee, J. Y.; Kim, S. H.; Yoon, J. S. [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2002-02-01

    It is known that high levels of radiation can cause significant damage by altering the properties of materials. A practical understanding of the effects of radiation - how radiation affects various types of materials and components - is required to design equipment to operate reliably in a gamma radiation environment. When designing equipment to operate in a high gamma radiation environment, such as will be present in a nuclear spent fuel handling facility, several important steps should be followed. In order to active test of the advanced spent fuel management process, the radiation-resistant analysis of the device and control component for active test which is concerned about the radiation environment is conducted. Also the system design process is analysis and reviewed. In the foreign literature, 'threshold' values are generally reported. the threshold values are normally the dose required to begin degradation in a particular material property. The radiation effect analysis for the device of vol-oxidation and metalization, which are main device for the advanced spent fuel management process, is performed by the SCALE 4.4 code. 5 refs., 4 figs., 13 tabs. (Author)

  4. New radiation technologies and methods for control of technological processes in metallurgy

    International Nuclear Information System (INIS)

    Zaykin, Yu.

    1996-01-01

    Radiation Technology of Metal and Ceramic Production with Enhanced Service Properties. Based on application of radiation technique in powder metallurgy the new technology for obtaining metals, alloys and ceramic materials with high service properties is worked out. Radiation processing of powder materials at the certain stage of the process leads to profound structure alterations at all further stages and eventually effects the properties of the resulting product. Theoretical calculation and experimental studies of electron-positron annihilation in powder-pressed samples showed that irradiation caused powder particles surface state changes favorable for further sintering and crystallization processes development. It is shown that irradiation of metal powders and powder-pressed samples by high energy electrons is technologically most efficient. The right choice of the type-and the mode of the radiation processing makes it possible to obtain metals, alloys and ceramic materials (Mo,Fe, W, Al, Ni, Cu, stainless steels, ceramics, etc.) with homogeneous structure and stable enhanced service properties. The project on radiation technology application to powder metallurgy represented by a group of authors was awarded with the diploma and the gold medal at the 22 International Exhibition of Inventions (Geneva, 1994). New Technologic Opportunities of the Chromium-Nickel Alloys Processing To obtain the required phase-structure state special methods of the chromium-nickel alloy processing for sensitive elastic devices production were worked out combining plastic deformation, thermal and radiation processing. It is shown that h-gbb phase transfer not observed before is possible in extremely non-equilibrium conditions under electron irradiation. It is established that the complex reaction of recrystallization and gb-phase deposition proceeds under electron irradiation at the room temperature when the certain threshold plastic deformation degree is reached that leads to the same

  5. High-energy radiation and polymers: A review of commercial processes and emerging applications

    International Nuclear Information System (INIS)

    Clough, R.L.

    2001-01-01

    Ionizing radiation has been found to be widely applicable in modifying the structure and properties of polymers, and can be used to tailor the performance of either bulk materials or surfaces. Fifty years of research in polymer radiation chemistry has led to numerous applications of commercial and economic importance, and work remains active in the application of radiation to practical uses involving polymeric materials. This paper provides a survey of radiation-processing methods of industrial interest, ranging from technologies already commercially well established, through innovations in the active R and D stage which show exceptional promise for future commercial use. Radiation-processing technologies are discussed under the following categories: cross-linking of plastics and rubbers, curing of coatings and inks, heat-shrink products, fiber-matrix composites, chain-scission for processing control, surface modification, grafting, hydrogels, sterilization, natural product enhancement, plastics recycling, ceramic precursors, electronic property materials, ion-track membranes and lithography for microdevice production. In addition to new technological innovations utilizing conventional gamma and e-beam sources, a number of promising new applications make use of novel radiation types which include ion beams (heavy ions, light ions, highly focused microscopic beams and high-intensity pulses), soft X-rays which are focused, coherent X-rays (from a synchrotron) and e-beams which undergo scattering to generate patterns

  6. Effect of 60Co radiation processing in mate (Ilex paraguariensis)

    International Nuclear Information System (INIS)

    Furgeri, Camilo

    2009-01-01

    The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from 60 Co at doses 0, 3, 5, 7 and 10 kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10 kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10 kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and

  7. Effect of 60CO radiation processing in mate (Ilex paraguariensis)

    International Nuclear Information System (INIS)

    Furgeri, Camilo

    2009-01-01

    The mate (Ilex paraguariensis), a native species from South America, is mainly consumed as typical beverage called chimarrao and terere. An important problem that has been afflicting this product since a long time is its natural fungal contamination responsible to affect its physical, health and nutritional qualities. In order to improve this product quality, radiation processing can be effective in reducing pathogens levels, with minimal nutritional and sensory changes. The aim of this study was to evaluate the effectiveness of gamma radiation from 60 Co at doses 0, 3, 5, 7 and 10kGy in reducing fungal contamination in mate, as well as analyze its nutritional and sensory characteristics. The following methodologies were applied: analysis of yeast and mold, total phenolic compounds analysis, antioxidant analysis, quantification of phenolic compounds and xanthines by liquid chromatography and sensory analysis. Microbiological analysis showed a decreasing molds and yeasts growth with increasing radiation doses. Regardless of the radiation dose applied there were no decrease of total phenolic compounds in both infusions. Chimarrao samples irradiated with 7 and 10kGy showed a decrease in the DPPH radical-scavenger activity, nevertheless for terere samples, there were no significant difference. Chimarrao chromatographic profile did not show a variation on xanthines quantification, however a 10kGy radiation dose caused a change to phenolic compounds quantitative profile. Terere samples did not show any significant difference to any analyzed compounds. Sensory analysis did not exhibit a significant difference between irradiated and non irradiated chimarrao samples, as well as between irradiated and non irradiated terere samples. It could be concluded that gamma radiation processing of mate may be a feasible alternative to industry, since there was a reduction on fungal contamination, without changes in sensory qualities and with minimum alterations in quantitative and

  8. Process for the production of radiation curable coating compositions containing microcapsules

    International Nuclear Information System (INIS)

    Lee, Y.; Shackle, D.R.

    1979-01-01

    A process for producing a radiation curable coating composition containing microcapsules comprises the steps of preparing a dispersion of substantially discrete microcapsules in a continuous phase, the continuous phase comprising a liquid volatile solvent, preparing a liquid radiation curable suspending medium, the liquid radiation curable suspending medium comprising one or more ethylenically unsaturated organic compounds having at least one terminal ethylenic group per molecule, mixing the dispersion of substantially discrete microcapsules in the continuous phase and the liquid radiation curable suspending medium with turbulent agitation to form an intimate mixture of the dispersion of microcapsules and the liquid radiation curable suspending medium, and applying heat and vacuum to the mixture, while maintaining the agitation, until the liquid volatile solvent is substantially removed from the mixture to form a dispersion of substantially discrete microcapsules in the liquid radiation curable suspending medium. The heat is applied to maintain the mixture at a temperature above the boiling point of the volatile solvent at the vacuum level

  9. Economic benefits analysis of listed companies in radiation processing

    International Nuclear Information System (INIS)

    Zhang Yingming; Xu Tao; Zhang Yue; Yang Bin; Zhao Wenying

    2012-01-01

    Radiation processing industry is an important part of civilian nuclear technology and develop rapidly during the past decade. Radiation modification of new materials industries use new technology to promote new product development and application and get good economic benefit. There are problems and bottlenecks during the development, such as how to implement the guideline of optimize the industrial structure and upgrade the product, and adapt the market develop law and need. By analysing the typical listed companies in this field together with the domestic economic development condition and future situation, we give the development strategy and method in the future. (authors)

  10. Alanine/ESR dosimetry system for routine use in radiation processing

    International Nuclear Information System (INIS)

    Kojima, T.; Haruyama, Y.; Tachibana, H.; Tanaka, R.; Okamoto, J.; Hara, H.; Kashiwazaki, S.

    1993-01-01

    A new alanine-polystyrene(PS) dosimeter prepared with simplified molding procedure and an automatic desk-top dose-reader of alanine dosimeter were developed for the purpose of routine use. Combination of these two allows us to apply a reliable alanine/ESR dosimetry system to routine dosimetric process control in industrial gamma radiation processing. (Author)

  11. Physicochemical processes occurring under action of ionizing radiation in sarcophagus

    International Nuclear Information System (INIS)

    Azarov, S.I.; Pshenichny, V.A.; Vilenskaya, L.N.; Korchevnaya, O.V.; Martseniuk, L.S.

    1998-01-01

    The result of analysis of environment ionization process inside Sarcophagus owing to alpha-, beta- and gamma-radiation processes with forming of ions. It is shown that as a result of ionization and physicochemical transformations gaseous mixtures, which are dangerous for personnel's health and can influence upon general technical safety of Sarcophagus, can release into atmosphere

  12. Dosimetry for radiation processing. Final report of the co-ordinated research project on characterization and evaluation of high dose dosimetry techniques for quality assurance in radiation processing

    International Nuclear Information System (INIS)

    2000-06-01

    In many Member States the use of large cobalt-60 gamma ray facilities and electron beam accelerators with beam energies from about 0.1 to 10 MeV for industrial processing continues to increase. For these processes, quality assurance relies on the application of well established dosimetry systems and procedures. This is especially the case for health regulated processes, such as the radiation sterilization of health care products, and the irradiation of food to eliminate pathogenic organisms or to control insect pests. A co-ordinated research project (CRP) was initiated by the IAEA in June 1995. Research contracts and research agreements in areas of high dose dosimetry were initiated to meet these challenges. The major goals of this CRP were to investigate the parameters that influence the response of dosimeters and to develop reference and transfer dosimetry techniques, especially for electron beams of energy less than 4 MeV and for high energy X ray sources (up to 5 MV). These will help to unify the radiation measurements performed by different radiation processing facilities and other high dose dosimetry users in Member States and encourage efforts to obtain traceability to primary and secondary standards laboratories. It will also aim to strengthen and expand the present International Dose Assurance Service (IDAS) provided by the IAEA

  13. Evaluation of phenolic compounds in mate (Ilex paraguariensis) processed by gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Furgeri, C.; Nunes, T.C.F.; Fanaro, G.B. [Instituto de Pesquisas Energeticas Nucleares, IPEN-CNEN/SP, Centro de Tecnologia das Radiacoes-Laboratory de Deteccao de Alimentos Irradiados, Av. Professor Lineu Prestes, 2242, Cidade Universitaria, CEP: 05508-900 Sao Paulo (Brazil); Souza, M.F.F.; Bastos, D.H.M. [Faculdade de Saude Publica, FSP/USP, Departamento de Nutricao-Av. Dr. Arnaldo, 715, CEP: 01246-904 Sao Paulo (Brazil); Villavicencio, A.L.C.H. [Instituto de Pesquisas Energeticas Nucleares, IPEN-CNEN/SP, Centro de Tecnologia das Radiacoes-Laboratory de Deteccao de Alimentos Irradiados, Av. Professor Lineu Prestes, 2242, Cidade Universitaria, CEP: 05508-900 Sao Paulo (Brazil)], E-mail: villavic@ipen.br

    2009-07-15

    The radiation food processing has been demonstrating great effectiveness in the attack of pathogenic agents, while little compromising nutritional value and sensorial properties of foods. The mate (Ilex paraguariensis), widely consumed product in South America, generally in the form of infusions with hot or cold water, calls of chimarrao or terere, it is cited in literature as one of the best sources phenolic compounds. The antioxidants action of these constituent has been related to the protection of the organism against the free radicals, generated in alive, currently responsible for the sprouting of some degenerative illness as cancer, arteriosclerosis, rheumatic arthritis and cardiovascular clutters among others. The objective of that work was to evaluate the action of the processing for gamma radiation in phenolic compounds of terere beverage in the doses of 0, 3, 5, 7 and 10 kGy. The observed results do not demonstrate significant alterations in phenolic compounds of terere beverage processed by gamma radiation.

  14. Evaluation of phenolic compounds in mate (Ilex paraguariensis) processed by gamma radiation

    International Nuclear Information System (INIS)

    Furgeri, C.; Nunes, T.C.F.; Fanaro, G.B.; Souza, M.F.F.; Bastos, D.H.M.; Villavicencio, A.L.C.H.

    2009-01-01

    The radiation food processing has been demonstrating great effectiveness in the attack of pathogenic agents, while little compromising nutritional value and sensorial properties of foods. The mate (Ilex paraguariensis), widely consumed product in South America, generally in the form of infusions with hot or cold water, calls of chimarrao or terere, it is cited in literature as one of the best sources phenolic compounds. The antioxidants action of these constituent has been related to the protection of the organism against the free radicals, generated in alive, currently responsible for the sprouting of some degenerative illness as cancer, arteriosclerosis, rheumatic arthritis and cardiovascular clutters among others. The objective of that work was to evaluate the action of the processing for gamma radiation in phenolic compounds of terere beverage in the doses of 0, 3, 5, 7 and 10 kGy. The observed results do not demonstrate significant alterations in phenolic compounds of terere beverage processed by gamma radiation.

  15. Evolutionary patterns and processes in the radiation of phyllostomid bats

    Directory of Open Access Journals (Sweden)

    Monteiro Leandro R

    2011-05-01

    Full Text Available Abstract Background The phyllostomid bats present the most extensive ecological and phenotypic radiation known among mammal families. This group is an important model system for studies of cranial ecomorphology and functional optimisation because of the constraints imposed by the requirements of flight. A number of studies supporting phyllostomid adaptation have focused on qualitative descriptions or correlating functional variables and diet, but explicit tests of possible evolutionary mechanisms and scenarios for phenotypic diversification have not been performed. We used a combination of morphometric and comparative methods to test hypotheses regarding the evolutionary processes behind the diversification of phenotype (mandible shape and size and diet during the phyllostomid radiation. Results The different phyllostomid lineages radiate in mandible shape space, with each feeding specialisation evolving towards different axes. Size and shape evolve quite independently, as the main directions of shape variation are associated with mandible elongation (nectarivores or the relative size of tooth rows and mandibular processes (sanguivores and frugivores, which are not associated with size changes in the mandible. The early period of phyllostomid diversification is marked by a burst of shape, size, and diet disparity (before 20 Mya, larger than expected by neutral evolution models, settling later to a period of relative phenotypic and ecological stasis. The best fitting evolutionary model for both mandible shape and size divergence was an Ornstein-Uhlenbeck process with five adaptive peaks (insectivory, carnivory, sanguivory, nectarivory and frugivory. Conclusions The radiation of phyllostomid bats presented adaptive and non-adaptive components nested together through the time frame of the family's evolution. The first 10 My of the radiation were marked by strong phenotypic and ecological divergence among ancestors of modern lineages, whereas the

  16. Evolutionary patterns and processes in the radiation of phyllostomid bats

    Science.gov (United States)

    2011-01-01

    Background The phyllostomid bats present the most extensive ecological and phenotypic radiation known among mammal families. This group is an important model system for studies of cranial ecomorphology and functional optimisation because of the constraints imposed by the requirements of flight. A number of studies supporting phyllostomid adaptation have focused on qualitative descriptions or correlating functional variables and diet, but explicit tests of possible evolutionary mechanisms and scenarios for phenotypic diversification have not been performed. We used a combination of morphometric and comparative methods to test hypotheses regarding the evolutionary processes behind the diversification of phenotype (mandible shape and size) and diet during the phyllostomid radiation. Results The different phyllostomid lineages radiate in mandible shape space, with each feeding specialisation evolving towards different axes. Size and shape evolve quite independently, as the main directions of shape variation are associated with mandible elongation (nectarivores) or the relative size of tooth rows and mandibular processes (sanguivores and frugivores), which are not associated with size changes in the mandible. The early period of phyllostomid diversification is marked by a burst of shape, size, and diet disparity (before 20 Mya), larger than expected by neutral evolution models, settling later to a period of relative phenotypic and ecological stasis. The best fitting evolutionary model for both mandible shape and size divergence was an Ornstein-Uhlenbeck process with five adaptive peaks (insectivory, carnivory, sanguivory, nectarivory and frugivory). Conclusions The radiation of phyllostomid bats presented adaptive and non-adaptive components nested together through the time frame of the family's evolution. The first 10 My of the radiation were marked by strong phenotypic and ecological divergence among ancestors of modern lineages, whereas the remaining 20 My were

  17. Radiation processing. Present situation of the applications in Europe

    International Nuclear Information System (INIS)

    Laizier, J.

    1977-01-01

    A review is given of radiation processings in Europe: sterilization, food irradiation, sewage treatment, cross-linking of polyethylenes, vinyl polychlorides, rubbers and polymers, electron beam drying of coatings