The effect of gamma ray irradiation on PAN-based intermediate modulus carbon fibers

International Nuclear Information System (INIS)

Li, Bin; Feng, Yi; Qian, Gang; Zhang, Jingcheng; Zhuang, Zhong; Wang, Xianping

2013-01-01

Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were conducted on PAN-based intermediate modulus carbon fibers to investigate the structure and surface hydrophilicity of the carbon fibers before and after gamma irradiation. Two methods were used to determine Young’s modulus of the carbon fibers. The results show that gamma ray irradiation improved the degree of graphitization and introduced compressive stress into carbon fiber surface. Gamma ray also improved the carbon fiber surface hydrophilicity through increasing the value of O/C and enhancing the quantity of oxygen functional groups on carbon fibers. No distinct morphology change was observed after gamma ray irradiation. The Young’s modulus of the fibers increased with increasing irradiation dose

On the decrease of ultimate elongation of gum elastomer by irradiation

International Nuclear Information System (INIS)

Ito, Masayuki

1986-01-01

The reason why the ultimate elongation of gum elastomer decreases by irradiation was studied. The sample used is tetrafluoroethylenepropylene copolymer vulcanized which is a heat resistant elastomer. The sample was irradiated by a electron beam at room temperature. Cross-linking predominate in the operation. (Case 1) Scission predominant condition (Case 2) was given by irradiation of Co-60 γ ray at 100 deg C. Alternative irradiation of γ ray and electron beam under above condition can keep the original cross-linking density by the appropriate choice of each of the doses. (Case 3) The three cases mentioned above involve all of the cases of radiation induced aging of elastomers. Therefor, the following explanation for three cases shows the reason why the ultimate elongation of gum elastomer decreases by irradiation. Case 1. Cross-linking predominant condition. Ultimate elongation is proportional to -0.5 power of the dose. This fact can be explicable by the model of Buche, i.e. the breaking of a short chain causes another to break and that so on throughout the whole sample. Case 2. Chain scission predominant condition. Ultimate elongation increases by irradiation for a certain dose. This fact can understand by the model of Buche. But from a certain dose ultimate elongation does not increase. In the period the structure of the sample turned to be the same structure as the low molecular weight amorphose polymer vulcanized. Case 3. Rate of cross-linking and scission is the same. The average chain length does not chainge in the condition. But the distribution of chain length became wider and wider by irradiation. The increase of short chain result the decrease in ultimate elongation. (author)

Operating experience with gamma ray irradiators

International Nuclear Information System (INIS)

Fraser, F.M.; Ouwerkerk, T.

1980-01-01

The experience of Atomic Energy of Canada, Limited (AECL) with radioisotopes dates back to the mid-1940s when radium was marketed for medical purposes. Cobalt-60 came on the scene in 1949 and within a few years a thriving business in cancer teletherapy machines and research irradiators was developed. AECL's first full-scale cobalt-60 gamma ray sterilizer for medical products was installed in 1964. AECL now has over 50 plants and 30 million curies in service around the world. Sixteen years of design experience in cobalt-60 sources, radiation shielding, safety interlock systems, and source pass mechanisms have made gamma irradiators safe, reliable, and easy to operate. This proven technology is being applied in promising new fields such as sludge treatment and food preservation. Cesium-137 is expected to be extensively utilized as the gamma radiation source for these applications

Livestock wastewater treatment by zeolite ion exchange and gamma-ray irradiation

International Nuclear Information System (INIS)

Lee, Sang Ryul; Kim, Tak Hyun; Lee, Myun Joo

2008-01-01

Livestock wastewater containing high concentrations of organic matters and ammonia-nitrogen has been known as one of the recalcitrant wastewater. It is difficult to treat by conventional wastewater treatment techniques. This study was carried out to evaluate the feasibility of zeolite ion exchange and gamma-ray irradiation treatment of livestock wastewater. The removal efficiencies of SCOD Cr and NH3-N were significantly enhanced by gamma-ray irradiation after zeolite ion exchange as a pre-treatment. However, the effects of zeolite particle size on the SCOD Cr and NH 3 -N removal efficiencies were insignificant. These results indicate that the combined process of zeolite ion exchange and gamma-ray irradiation has potential for the treatment of livestock wastewater

Inactivation of HTB63 human melanoma cells by irradiation with protons and gamma rays.

Science.gov (United States)

Ristic-Fira, Aleksandra; Petrovic, Ivan; Todorovic, Danijela; Koricanac, Lela; Vujèic, Miroslava; Demajo, Miroslav; Sabini, Gabriella; Cirrone, Pablo; Cuttone, Giacomo

2004-12-01

The effects of single irradiation with gamma rays and protons on HTB63 human melanoma cell growth were compared. The exponentially growing cells were irradiated with gamma rays or protons using doses ranging from 2-20 Gy. At 48 h of post-irradiation incubation under standard conditions, cell survival and induction of apoptotic cell death were examined. The best effect of the single irradiation with gamma rays was the reduction of cell growth by up to 26% (p=0.048, irradiation vs. control), obtained using the dose of 16 Gy. The same doses of proton irradiation, having energy at the target of 22.6 MeV, significantly inhibited melanoma cell growth. Doses of 12 and 16 Gy of protons provoked growth inhibition of 48.9% (p=0.003, irradiation vs. control) and 51.2% (p=0.012, irradiation vs. control) respectively. Irradiation with 12 and 16 Gy protons, compared to the effects of the same doses of gamma rays, significantly reduced melanoma cell growth (p=0.015 and p=0.028, protons vs. gamma rays, respectively). Estimated RBEs for growth inhibition of HTB63 cells ranged from 1.02 to 1.45. The electrophoretical analyses of DNA samples and flow cytometric evaluation have shown a low percentage of apoptotic cells after both types of irradiation. The better inhibitory effect achieved by protons in contrast to gamma rays, can be explained considering specific physical properties of protons, especially taking into account the highly localized energy deposition (high LET).

Gamma ray irradiation characteristics of SM fibers

International Nuclear Information System (INIS)

Ito, Ryuichi; Okano, Hiroaki; Hashiba, Keichi; Nakai, Hisanori

1987-01-01

1.3 μm range single mode (SM) optical fibers have been used for wide application of mainly long distance communication. At present, in order to realize the larger capacity and longer distance between relay points, the development of 1.5 μm range SM fibers of low dispersion and small loss has been actively promoted. As for the radiation withstanding property of SM fibers, report is scarce. The authors reported on the gamma ray irradiation characteristics of 1.3 μm range SM fibers, but since 1.5 μm range SM fibers are designed with the different structure from that of 1.3 μm fibers, it is necessary to evaluate from new viewpoint. In this report, mainly on the structure having triangular distribution, the effect that the manufacturing condition and the structural defects of glass exert on the gamma ray irradiation characteristics is described. The specimens were mainly dispersion shift type fibers (DSF), and for comparison, single window, double window and 1.3 μm SM fibers were examined. Co-60 gamma ray was irradiated, and the optical loss and electron spin resonance were measured. By low temperature and low speed drawing, the good result in the optical loss was obtained. The presence of oxygen at the time of sintering materials had no effect. The dependence of the ESR on the drawing condition was not very remarkable. (Kako, I.)

Thermoluminescence of Simulated Interstellar Matter after Gamma-ray Irradiation

OpenAIRE

Koike, K.; Nakagawa, M.; Koike, C.; Okada, M.; Chihara, H.

2002-01-01

Interstellar matter is known to be strongly irradiated by radiation and several types of cosmic ray particles. Simulated interstellar matter, such as forsterite $\\rm Mg_{2}SiO_{4}$, enstatite $\\rm MgSiO_{3}$ and magnesite $\\rm MgCO_{3}$ has been irradiated with the $\\rm ^{60}Co$ gamma-rays in liquid nitrogen, and also irradiated with fast neutrons at 10 K and 70 K by making use of the low-temperature irradiation facility of Kyoto University Reactor (KUR-LTL. Maximum fast neutron dose is $10^{...

Inhibitory mechanism of low-dose, whole-body irradiation with gamma-rays against tumor metastasis

International Nuclear Information System (INIS)

Yasuhiro Ohsima; Mitsutoshi Tukimoto; Shuji Kojima

2007-01-01

Complete text of publication follows. A lot of beneficial effects of low-dose irradiation are well known. Of them, an inhibitory effect of the radiation on lung metastasis is reported so far. It has been reported that low-dose whole-body irradiation with gamma rays enhanced cytotoxic immune response as one of the mechanisms. In our laboratory, it has been confirmed an enhancement of natural killer activity in mice irradiated with whole-body 0.5Gy gamma-rays. Metastasis is accomplished by multistep process, involving basement membrane destruction, local invasion, intravasation, survival in the bloodstream, extravasation into distant organs, and proliferation at the target site. Besides, a lot of growth factors and proteases are involved in these steps. As to mechanism of inhibition of tumor metastasis induced by low-dose whole-body irradiation, studies from the standpoint of tumor invasion have not been reported. Here, inhibitory effect of 0.5Gy whole-body gamma-ray irradiation on tumor metastasis and its mechanism were examined in pulmonary metastasis model mice injected with B16 melanoma cells. Consequently, 0.5Gy whole-body gamma ray irradiation significantly suppressed colony formation in the lungs. Expression of matrix metalloproteinase- 2 (MMP- 2), a proteinase related to metastasis, in lung tissues was suppressed by the radiation. Alteration of tissue inhibitor of matrix metalloproteinase (TIMP) after the gamma-ray irradiation was examined. Expression of TIMP-1 and TIMP-2 mRNA in the lungs were significantly increased. In order to clarify the inhibitory effect obtained in the in vivo metastatic lung cancer model mice, we studied effects of gamma-rays on cell proliferation, alterations of mRNA and proteins related to tumor metastasis in cultured B16 melanoma cells. Proliferation of B16 melanoma cells was decreased in a dose-dependent manner. MMP-2 mRNA expression was not altered in any doses of gamma-rays. Thought expression of the protein was slightly

Influence of gamma irradiation in the thermoplastic elastomer (TPE); Influência da radiação gama no elastômero termoplástico (TPE)

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Camila B.; Parra, Duclerc F.; Marchini, Leonardo G., E-mail: camila@ba7.com.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

2017-07-01

The TPE is the nomenclature used for the thermoplastic elastomer, which is also known as thermoplastic rubber. It belongs to an under-researched class of engineering plastics, however, in recent years there has been steady growth due to its important and unusual combination of properties. During its use, it behaves like an elastomer, but, unlike traditional elastomers (vulcanized rubbers), it can be processed using conventional technologies and equipment used for thermoplastics, such as extrusion and injection. The processing of polymers, such as TPE by means of radiation, constitutes a technological area dedicated to the study of the physical and chemical effects caused by high energy radiation, such as gamma radiation. Thus the objective of this work is to evaluate the mechanical and thermal properties of TPE irradiated by {sup 60}Co source of gamma radiation in different doses. The thermoplastic elastomer being modified by means of ionizing radiation at doses of 5, 10, 20, 30, 50 and 100 kGy the effects of the radiation on the mechanical and thermal properties of this material are evaluated through the tests of tensile tests, TGA, FTIR and Fluency Index.

Electrical characteristics of {sup 60}Co {gamma}-ray irradiated MIS Schottky diodes

Energy Technology Data Exchange (ETDEWEB)

Tataroglu, A. [Department of Physics, Faculty of Arts and Sciences, Gazi University, 06500 Ankara (Turkey)]. E-mail: ademt@gazi.edu.tr; Altindal, S. [Department of Physics, Faculty of Arts and Sciences, Gazi University, 06500 Ankara (Turkey)

2006-11-15

In order to interpret the effect of {sup 60}Co {gamma}-ray irradiation dose on the electrical characteristics of MIS Schottky diodes, they were stressed with a zero bias at 1 MHz in dark and room temperature during {gamma}-ray irradiation and the total dose range was 0-450 kGy. The effect of {gamma}-ray exposure on the electrical characteristics of MIS Schottky diodes has been investigated using C-V and G/{omega}-V measurements at room temperature. Experimental results show that {gamma}-ray irradiation induces a decrease in the barrier height {phi} {sub B} and series resistance R {sub s}, decreasing with increasing dose rate. Also, the acceptor concentration N {sub A} increases with increasing radiation dose. The C-V characteristics prove that there is a reaction for extra recombination centers in case of MIS Schottky diodes exposed to {gamma}-ray radiation. Furthermore, the density of interface states N {sub ss} by Hill-Coleman method increases with increasing radiation dose. Experimental results indicate that the interface-trap formation at high irradiation dose is reduced due to positive charge build-up in the Si/SiO{sub 2} interface (due to the trapping of holes) that reduces the flow rate of subsequent holes and protons from the bulk of the insulator to the Si/SiO{sub 2} interface.

Effect of gamma-ray and electron irradiation on the response of solid-state track detectors

International Nuclear Information System (INIS)

Fukuda, Kyue

1980-01-01

Specimens of muscovite mica were first exposed to fission fragments and then to various gamma-ray fields from a 60 Co source ranging from 1.9 x 10 3 to 1.6 x 10 4 Mrad dose. The results show that the average etched width of fission-fragment tracks decreases with increasing gamma-ray dose. Shallow pits were observed in etched specimens when the gamma-ray dose exceeded 5 x 10 3 Mrad. Numerous shallow etch pits caused by the gamma-ray irradiation interfered with the observation of fission tracks in the specimens. No shallow etch pits were observed in the specimen annealed for 100 min at 600 0 C before the gamma-ray irradiation. Pre-annealing extends the ''safety limits'' of gamma background below which muscovite mica can be used to observe fission tracks without any gamma-ray interference. Gamma-ray and electron irradiation caused significant increase of the resistance to thermal decomposition of muscovite mica. The resistance increased markedly in the dose range from 5 x 10 3 to 8 x 10 3 Mrad. These phenomena suggest the use of mica to assess radiation doses of gamma rays and electrons up to several thousand megarads. (author)

Effect of gamma rays on crystalline materials during irradiation in a reactor

International Nuclear Information System (INIS)

Nikolaenko, V.A.; Karpukhin, V.I.; Gordeev, V.G.

1995-01-01

The article presents and discusses the results of experiments to determine the effect of gamma rays on the change in the properties of diamond, graphite, and structural steel. The materials were irradiated in a VVER type reactor. For diamonds, the effect on the annealing of defects was investigated. As gamma ray intensity increased, the crystal lattice expansion and defect concentration increased. Graphite lattice expansion and the mechanical properties of structural steel were also examined. Graphite lattice expansion increased with increased neutron flux and decreased irradiation temperature. Changes in the impact toughness of structural steel correlated precisely to the gamma ray flux in the experiments. 6 refs., 3 figs

Sensitivity of P-Channel MOSFET to X- and Gamma-Ray Irradiation

Directory of Open Access Journals (Sweden)

Milić Pejović

2013-01-01

Full Text Available Investigation of Al-gate p-channel MOSFETs sensitivity following irradiation using 200 and 280 kV X-ray beams as well as gamma-ray irradiation of 60Co in the dose range from 1 to 5 Gy was performed in this paper. The response followed on the basis of threshold voltage shift and was studied as a function of absorbed dose. It was shown that the most significant change in threshold voltage was in the case of MOSFET irradiation in X-ray fields of 200 kV and when the gate voltage was +5 V. For practical applications in dosimetry, the sensitivity of the investigated MOSFETs was also satisfactory for X-ray tube voltage of 280 kV and for gamma rays. Possible processes in gate oxide caused by radiation and its impact on the response of MOSFETs were also analyzed in this paper.

Tuning surface properties of graphene oxide quantum dots by gamma-ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Lu, Shunkai; Liao, Fan, E-mail: fliao@suda.edu.cn; Wang, Tao; Zhu, Lili; Shao, Mingwang, E-mail: mwshao@suda.edu.cn

2016-07-15

Gamma-ray irradiation was employed to tune surface properties of graphene oxide quantum dots (GOQDs), such as functional groups and defect density. The GOQDs were first oxidized under γ-ray irradiation with doses ranging from 0 to 200 kGy, and then reduced under larger irradiation doses from 200 to 400 kGy. In other words, both the defect density and the number of surface functional groups increased first and then decreased along with the increasing irradiation dose. This process was confirmed with UV–visible absorption, X-ray photoelectron spectroscopy, Raman spectra and Fourier transform infrared spectra. In order to estimate their π-conjugated content, the GOQDs were served to quench the fluorescence of Rhodamine 6 G. The results showed that there existed a positive relationship between the π-conjugated content and the static quenching coefficient V{sub q}Na, which might have a potential value. - Highlights: • The conjugate extent and hydrophily of GOQDs decreased along with irradiation dose. • Gamma-ray irradiation weakens the quenching effect of GOQDs. • Quenching mechanism is a combination of dynamic and static quenching.

Effect of Low Dose gamma-ray Irradiation on the Germination and Growth in Red Pepper (Capcicum annuum L.)

International Nuclear Information System (INIS)

Lee Eun-Kyung; Kim Jae-Sung

1998-01-01

This study was conducted to determine the effect of low dose gamma-ray irradiation in red pepper. The germination percentage, plant, the number of flower, chlorophyll contents, leaf length and width were observed from plants grown with red pepper seeds irradiated with various low dose of gamma-ray. The germination percentage of irradiation group treatmented gamma-ray was much higher than that of the control. Specially the germination percentage after sowing red pepper seeds on paper towel was higher than 1,000 and 2,000 rad irradiation group. The height of plants grown with red pepper seeds irradiated with gamma-ray was increased in 100, 200 and 400 rad irradiation group compared to that of the control. The height of plant from 2,400 rad irradiation group, however, was shorter than that of the control. Nutrient contents of leaves of plants grown with red pepper seeds irradiated with various dose of gamma-ray were significantly increased in 800 and 1,200 rad irradiation group. Electric conductivity (EC) of the water used for seed germination was lower irradiation group than control group. Therefore, there was the possibility to increase the germination and plant growth with gamma-ray of adequate low dose

One-step synthesis of graphene-Pt nanocomposites by gamma-ray irradiation

International Nuclear Information System (INIS)

Tokai, Akihiro; Okitsu, Kenji; Hori, Fuminobu; Mizukoshi, Yoshiteru; Iwase, Akihiro

2016-01-01

We developed a one-step gamma-ray irradiation method to synthesize nanocomposites composed of graphene and Pt nanoparticles from aqueous solution containing graphene and Pt(IV) complex ions in the presence of 2-propanol (IPA) or sodium dodecyl sulfate (SDS). It was confirmed that gamma-ray irradiation provided carbonyl groups on graphene and Pt nanoparticles formed from the radiolytic reduction of Pt(IV) complex ions were deposited onto the carbonyl modified graphene. In the presence of IPA, small Pt nanoparticles were deposited on graphene, but large Pt nanoparticles were deposited in the presence of SDS: the size of Pt nanoparticles formed was larger in the presence of SDS than IPA. Based on the results, formation and deposition mechanisms of Pt nanoparticles were proposed. - Highlights: • Graphene-Pt nanocomposites were synthesized by gamma-ray irradiation. • Reduction of Pt(IV) complex ions and oxidation of graphene occurred simultaneously. • Smaller Pt nanoparticles were formed in the presence of IPA than SDS. • Mechanism for formation of graphene-Pt nanocomposites was proposed.

Economics of gamma irradiation processing

International Nuclear Information System (INIS)

Tani, Toshio

1980-01-01

The gamma-ray irradiation business started at the Takasaki Laboratory of Japan Atomic Energy Research Institute. The irradiation facilities were constructed thereafter at various sites. The facilities must accept various types of irradiation, and must be constructed as multi-purpose facilities. The cost of irradiation consists of the cost of gamma sources, construction expense, personnel expense, management expense, and bank interest. Most of the expenses are considered to be fixed expense, and the amount of irradiation treatment decides the original costs of work. The relation between the irradiation dose and the construction expense shows the larger facility is more economical. The increase of amount of treatment reduces the original cost. The utilization efficiency becomes important when the amount of treatment and the source intensity exceed some values. The principal subjects of gamma-ray irradiation business are the sterilization of medical tools and foods for aseptic animals, the improvement of quality of plastic goods, and the irradiation of foods. Among them, the most important subject is the sterilization of medical tools. The cost of gamma irradiation per m 3 in still more expensive than that by ethylene oxide gas sterilization. However, the demand of gamma-ray irradiation is increasing. For the improvement of quality of plastic goods, electron irradiation is more favourable than the gamma irradiation. In near future, the economical balance of gamma irradiation can be achieved. (Kato, T.)

Effects of gamma-rays irradiation on tracking resistance of organic insulating materials

Energy Technology Data Exchange (ETDEWEB)

Du, Boxue; Suzuki, Akio; Kobayashi, Shigeo [Tokyo Univ. of Agriculture and Technology, Koganei (Japan). Faculty of Technology

1996-04-01

This paper describes the influence of gamma-rays irradiation on tracking failure of organic insulating materials by use of the IEC Publ.112 method. Tracking resistance of organic insulating materials under wet polluted condition has been studied by many investigators with a test method of the IEC Publ.112. The investigations on irradiation effects on tracking resistance should be enhanced due to the increasing usage of organic insulating materials in the radiation environments. The tracking resistance seems to be affected by gamma-irradiation, but the knowledge on the influence of gamma-irradiation is quite a few and systematic studies are needed. In this paper, modified polyphenylene oxide, polybutylene naphthalate, modified polycarbonate and polybutylene terephthalate which were irradiated in air until 1x10{sup 7}R and 1x10{sup 8}R with dose rate of 10{sup 6}R/hr using {sup 60}Co gamma-source have been employed. The total dose effects on the number of drops to tracking failure, contact angle and charges of scintillation have been studied. As the total doses are increased, the number of drops to tracking failure decreases with polybutylene terephthalate. On the other hand, the number of drops to tracking failure increases with polybutylene naphthalate and modified polycarbonate when the total doses are increased. The effects of gamma-rays irradiation on tracking failure are due to radiation-induced degradation or cross-linking of organic insulating materials. When the organic insulating materials are degraded by gamma-irradiation, the tracking resistance decreases, but for cross-linking type materials, the tracking resistance increases. (author)

Results on neutron and gamma-ray irradiation of electrolytic tiltmeters

International Nuclear Information System (INIS)

Calderon, A.; Calvo, E.; Figueroa, C.F.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Vila, I.; Virto, A.L.; Arce, P.; Barcala, J.M.; Ferrando, A.; Fuentes, J.; Josa, M.I.; Luque, J.M.; Molinero, A.; Navarrete, J.; Oller, J.C.; Valdivieso, P.; Fenyvesi, A.; Molnar, J.

2004-01-01

We report on irradiation studies done to a sample of high-precision electrolytic tiltmeters with gamma-rays, up to a maximum dose of 150 kGy, and neutrons, up to a maximum fluence of 1.5x10 14 cm -2 . The effect of the irradiation on their performance is discussed

Effect of {gamma}-ray irradiation on the magnetic properties of NdFeB and Fe-Cr-Co permanent magnets

Energy Technology Data Exchange (ETDEWEB)

Gao, R.S. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Zhen, L. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)]. E-mail: zhenl@hit.edu.cn; Li, G.A. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Xu, C.Y. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Shao, W.Z. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

2006-07-15

The effect of {gamma}-ray irradiation on the magnetic properties of NdFeB and Fe-Cr-Co permanent magnets has been investigated. The magnetic flux loss of two kinds of magnets before and after irradiation was measured. Results show that the effect of {gamma}-ray irradiation on the magnetic properties of sintered NdFeB is not so obvious as that on Fe-Cr-Co magnet. Irradiation-induced damage from {gamma}-ray for the Fe-Cr-Co magnets was characterized for the first time. The decline of permanent magnetic properties of Fe-Cr-Co magnet induced by {gamma}-ray irradiation is reversible except for the maximum energy product (BH){sub max}. The difference of coercivity mechanism between these two kinds of permanent magnets is responsible for the different dependence of magnetic properties loss induced by {gamma}-ray irradiation.

Effect of gamma irradiation dose on the fabrication of α-elastin nanoparticles by gamma-ray crosslinking

International Nuclear Information System (INIS)

Fujimoto, Mari; Takeda, Mayuko; Okamoto, Kouji; Furuta, Masakazu

2011-01-01

Nanoparticles were prepared utilizing the thermosensitive aggregation of α-elastin and gamma-ray crosslinking. We investigated the effect of the α-elastin irradiation doses to verify the yield of crosslinked nanoparticles. Aqueous solution of α-elastin (10 mg/ml) was used for the aggregation on raising temperature above its cloudy point (CP), followed by gamma-ray crosslinking. A slow heating process (1.9 o C/min) effectively led to aggregation of polypeptide and irradiation with more than 15 kGy yielded stable crosslinked nanoparticles with diameters less than ca. 200 nm and a narrow size distribution.

Effect of gamma irradiation dose on the fabrication of {alpha}-elastin nanoparticles by gamma-ray crosslinking

Energy Technology Data Exchange (ETDEWEB)

Fujimoto, Mari; Takeda, Mayuko [Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8570 (Japan); Okamoto, Kouji [Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502 (Japan); Furuta, Masakazu, E-mail: mfuruta@b.s.osakafu-u.ac.j [Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8570 (Japan)

2011-02-15

Nanoparticles were prepared utilizing the thermosensitive aggregation of {alpha}-elastin and gamma-ray crosslinking. We investigated the effect of the {alpha}-elastin irradiation doses to verify the yield of crosslinked nanoparticles. Aqueous solution of {alpha}-elastin (10 mg/ml) was used for the aggregation on raising temperature above its cloudy point (CP), followed by gamma-ray crosslinking. A slow heating process (1.9 {sup o}C/min) effectively led to aggregation of polypeptide and irradiation with more than 15 kGy yielded stable crosslinked nanoparticles with diameters less than ca. 200 nm and a narrow size distribution.

Effect of /sup 60/Co. gamma. -rays on polyphenyl methacrylate obtained by. gamma. -ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Raghunath, S.; Rao, M.H.; Rao, K.N. (Bhabha Atomic Research Centre, Bombay (India). Chemistry Div.)

1983-01-01

Polyphenyl methacrylate of different molecular weights Msub(n) 13000, 34500 and crosslinked polymer prepared by /sup 60/Co ..gamma..-irradiation has been irradiated with /sup 60/Co ..gamma..-rays at 300 K. G(scission) of the 13000 molecular weight polymer was 15. The crosslinked polymer undergoes both degradation and crosslinking. G(x) value determined for that polymer is approx. 9. The gaseous product consists largely of CO with some CO/sub 2/ and H/sub 2/. Hydrocarbon gases were not detected. The yield of H/sub 2/ is only to the extent of 2 to 5% of the total gas and it is assumed that majority of scission takes place at the ester linkage. On the basis of the estimation of phenol and benzene, a mechanism for degradation and crosslinking is proposed.

Effect of irradiation (gamma rays) on the biology of Eimeria tenella oocysts

Energy Technology Data Exchange (ETDEWEB)

Bajwa, R.S.; Gill, B.S.

1977-01-01

Effect of gamma rays on the biology of the progeny of the irradiated Eimeria tenella oocysts was investigated. The parent inoculum of sporulated oocysts was exposed to 5 to 60 kR (gamma rays). These oocysts were fed to chicks. The oocysts voided by the chicks were collected and sporulated. The sporulation rate, pathogenicity, immunogenicity and reproduction potential of these oocysts--the progeny of the irradiated oocysts--were compared with those of the unirradiated oocysts. It was observed that increase of irradiation dose caused progressive decrease in the pathogenicity of the oocyst suspension. The oocysts exposed to 30 and 40 kR produced only mild infections whereas those exposed to 50 kR and above were noninfective. No difference in pathogenicity, immunogenicity and reproduction potential of unirradiated oocysts and the oocysts progeny of the irradiated oocysts was seen. It was concluded, therefore, that the effect of irradiation was limited to the inoculum exposed to it, and was not transmissible to the progeny of the irradiated oocysts.

Effect of spirit irradiation with 60Co gamma-rays

International Nuclear Information System (INIS)

Gwardys, S.

1975-01-01

A few sorts of spirit were irradiated with a dose of 1 or 5 Mrad of 60 Co gamma-rays. Then the chemical composition of spirits was investigated. It was found that as a result of irradiation the content of acids, esters, acetal aldehydes and methanol increases, while the strength of higher alcohols decreases slightly. The changes of compounds content in particular spirits are dependent on radiation doses and chemical composition before irradiation. It was also discovered that spirit irradiation causes decrease or even disappearance of characteristic - for given spirits - maxima of UV absorption. (Z.M.)

Study of the semiconductor properties by irradiation, 8. Study of trapping center by. gamma. -ray on Si wafer

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Koji; Shioya, Hitoshi; Nagamatsu, Yasuhiko; Ogura, Shoji [Miyazaki Univ. (Japan). Faculty of Engineering

1983-08-01

In order to know the effects of ..gamma..-ray irradiation on n-type Si-wafers, the author did ..gamma..-ray irradiation experiments on n-type Si-wafers. They then observed the trapping center by using DLTS and ICTS equipments. The trapping center level, which is produced by ..gamma..-ray, is about 0.49 eV. In addition, the authors discuss the recombination rate.

Thermoluminescence of simulated interstellar matter after gamma-ray irradiation. Forsterite, enstatite and carbonates

Science.gov (United States)

Koike, K.; Nakagawa, M.; Koike, C.; Okada, M.; Chihara, H.

2002-08-01

Interstellar matter is known to be strongly irradiated by cosmic radiation and several types of cosmic ray particles. Simulated interstellar matter, such as synthesized forsterite (Mg2SiO4), enstatite (MgSiO3) and magnesite (MgCO3), has been irradiated with 60Co gamma-rays in liquid nitrogen, and also irradiated with fast neutrons at 10 K and 70 K by making use of the low-temperature irradiation facility of the Kyoto University Reactor (KUR-LTL. Maximum fast neutron dose is 1017nf /cm2). After irradiation, samples are stored in liquid nitrogen for several months to allow the decay of induced radioactivity. We measured the luminescence spectra of the gamma ray irradiated samples during warming to 370 K using a spectrophotometer. For the forsterite and magnesite, the spectra exhibit a rather intense peak at about 645-655 nm and 660 nm respectively, whereas luminescence scarcely appeared in the natural olivine sample. The spectra of forsterite is very similar to the ERE of the Red Rectangle.

Study on shelf life extension of papayas irradiated by /sup 60/Co gamma-rays

Energy Technology Data Exchange (ETDEWEB)

Chang, M.S.; Chen, M.D.; Lin, C.T.; Fu, Y.K.

1984-11-01

Papayas are one of the main fresh fruits in Taiwan area. Papaya fruits were treated with hot water to pasteurize peels followed by /sup 60/Co gamma-ray irradiation to extend the ripening time. The purpose of synergetic methods is to extend the shelf life of papaya fruits. This experiment was carried out by seven treatments, which were: (1) control group, (2) hot water treatment only, (3) hot water treatment with a 25 krad ..gamma..-irradiation, (4) hot water treatment with a 50 krad ..gamma..-irradiation, (5) hot water treatment with a 75 krad ..gamma..-irradiation, (6) 75 krad ..gamma..-irradiation only, and (7) hot water treatment with a 100 krad ..gamma..-irradiation. The items of observation were: surface yellowing, surface decaying, quality of texture, and length of period lasted after irradiation for 50% marketable papayas. The results of this study showed that a shelf-life extension of six days could be obtained for papayas subjected to hot water (50 to 55/sup 0/C) treatment and a 100 krad irradiation. 3 refs., 2 figs., 2 tabs.

Influence of gamma-ray irradiation on Faraday effect of Cu-doped germano-silicate optical fiber

Energy Technology Data Exchange (ETDEWEB)

Kim, Youngwoong; Ju, Seongmin; Jeong, Seongmook; Jang, Myoung-Jin [Department of Physics and Photon Science, School of Information and Communications, Gwangju Institute of Science and Technology, 261 Cheomdan-gwagiro, Buk-Gu, Gwangju 500-712 (Korea, Republic of); Kim, Jong-Yeol; Lee, Nam-Ho; Jung, Hyun-Kyu [Nuclear Convergence Technology Development Department, Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Han, Won-Taek, E-mail: wthan@gist.ac.kr [Department of Physics and Photon Science, School of Information and Communications, Gwangju Institute of Science and Technology, 261 Cheomdan-gwagiro, Buk-Gu, Gwangju 500-712 (Korea, Republic of)

2015-02-01

Influence of gamma-ray irradiation on the Faraday effect of the Cu-doped germano-silicate optical fiber was investigated. The Verdet constant of the gamma-ray irradiated optical fiber at 660 nm was measured to be 3.07 rad T{sup −1} m{sup −1}, 1.46 times larger than that of before the irradiation at total dose of 1200 Gy. Cu-related radiation-induced defect centers and Cu metal particles which were reduced from Cu{sup 2+} ions by the irradiation are thought to be responsible for the increase in the Verdet constant of the optical fiber.

Gamma ray irradiation induced optical band gap variations in silica sol-gel doped sucrose

International Nuclear Information System (INIS)

Marzouki, F.; Farah, K.; Hamzaoui, A.H; Ben Ouada, H

2015-01-01

The silica xerogels doped sucrose was prepared via sol-gel process and exposed at room temperature to different doses of high energy ("6"0Co) gamma irradiation. Changes in the UV-visible and FTIR spectra of pristine and irradiated xerogels with varying of gamma doses rays show variation in the gap energy. It was found that energy gap of the investigated silica xerogels decreases with increasing the gamma irradiation doses. Thereby the irradiated samples reveal behaviour changes, from an insulator (Eg ∼5,8 eV) towards a semiconductor with (Eg ∼ 3.5 eV).

Depolymerization of schizophyllan by gamma-ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Tabata, Kengo; Ito, Wataru; Hirata, Akio; Kojima, Takemasa [Taito Co. Ltd., Kobe (Japan). Research Lab.

1992-11-01

Schizophyllan, an antitumor (1 [yields] 3)-[beta]-D-glucan that takes on a triple helical structure in aqueous solution, was irradiated with gamma-ray at doses of 0.058 to 8.4 Mrad. The molecular weight of the polysaccharide decreased as the dose of radiation increased, and the number of reducing group increased. Methylation analysis by enzymic hydrolysis with exo-[beta]-1,3-glucanase and antitumor tests showed that the polysaccharide after irradiation at 0.058 or 0.26 Mrad had essentially the same chemical structure and antitumor activity as native schizophyllan. Treatment at 2 or 8.4 Mrad caused changes in the chemical structure and antitumor activity. The depolymerization mechanism seemed to be different from that caused by ultrasonic treatment or hydrodynamic shearing, because irradiation most readily caused changes in the chemical structure and antitumor activity. (author).

Studies on the influences of. gamma. -ray irradiation upon food additives, (7). Radiolysis of 5'-nucleotides due to. gamma. -ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Hamada, M [Shimonoseki Univ. of Fisheries, Yamaguchi (Japan); Gohya, Y; Ishio, S

1981-08-01

The effect of ..gamma..-ray irradiation on inosine-5'-monophosphate (5'-IMP) and guanosine-5'-monophosphate (5'-GMP) in aqueous solution and in ''kamaboko'' was investigated to evaluate the rate of decomposition and to elucidate the safety of the decomposed products, under the concentration of 0.025% and irradiation dose of 3.00 x 10/sup 5/ rad. Ribose-phosphate compound, inorganic phosphate and 2'-, 3'-nucleotides were ascertained when either 5'-IMP or 5'-GMP aqueous solution was irradiated. G value of 5'-IMP and 5'-GMP in aqueous solution were estimated to be 1.29 and 0.97, respectively. The radiolysis of both 5'-IMP and 5'-GMP in ''kamaboko'' was hardly proceeded.

Influence Of Gamma Irradiation On Mechanical And Thermal Properties Of Waste Polyethylene / Nitrile Butadiene Rubber Blend

International Nuclear Information System (INIS)

Aly, R.O.

2012-01-01

Gamma irradiation radical-radical interaction crosslinking of elastomers and thermoplastic is a special type of crosslinking technique that has gained importance over conventional chemical crosslinking method as process is fast, pollution free and simple. In this study, a blend polymer, based on waste polyethylene and nitrile butadiene rubber, has been irradiated with gamma rays then mechanically and thermally investigated at varying NBR content. FTIR and SEM techniques were used in addition to the swelling behaviour by toluene solvent to emphasize the blend formation. The mechanical properties like tensile strength, elongation at break and modulus at different elongations were studied and compared with those of non-irradiated ones. A relatively low radiation dose was found effective in improving the level of mechanical properties. Differential scanning calorimeter and thermogravimetric analysis were used to study the thermal characteristics of the irradiated polymer. Enhancement in thermal stability has been observed for higher NBR containing blends and via radiation-induced crosslinking up to ≅ 50 kGy

Commercial gamma-ray irradiation plant in Japan

Energy Technology Data Exchange (ETDEWEB)

Tomita, K; Sugimoto, S [Radia Industry Co. Ltd., Gunma (Japan)

1977-01-01

In 1973, a commercial gamma-ray irradiation plant was constructed in Takasaki, about 100 km north of Tokyo. The plant has been used for both production of irradiated commercial products and irradiation services. The irradiation services are being made available for sterilization of both medical appliances such as disposable medical syringes, catheters, surgical sutures, and sterilization of feed stuffs for animals. Treatment of plastic materials and colouring of both crystals and glass wares are also undertaken. This facility can accommodate 600 kCi of /sup 60/Co and has a monthly treating capacity of 12,000 packages ( a standard carton of 340 mm x 400 mm x 500 mm) at an irradiation dose of 1 Mrad/hr. A receiving port for packages is on the second floor and the outlet of the irradiated packages on the first floor, with three lines of connecting loop conveyors between them, and the irradiation compartment in the center section. The space arrangement of the facility is well designed and gravity can be utilized for the transportation of the packages. Polymer impregnated coral is put on the market for ornamental building material on an order contract basis.

Effects of gamma-ray irradiation on cellulase secretion of Trichoderma reesei

International Nuclear Information System (INIS)

Tamada, M.; Kasai, N.; Kaetsu, I.

1987-01-01

Trichoderma reesei was irradiated with gamma rays to investigate the effects of different dosages on cellulase production. Doses above 0.7 kGy induced cell lysis. Cell growth began to be obstructed at 2.0 kGy. As a result, the cells irradiated at 2.0 kGy secreted 1.8 times as much cellulase as the untreated cells

Effect of large dose gamma-ray irradiation on polyimide

International Nuclear Information System (INIS)

Morita, Yohsuke; Watanabe, Kiyoshi; Yagyu, Hideki.

1988-01-01

In the radiation environment of atomic energy, space and so on, with the heightening of the performance of equipment, the organic materials having the radiation resistance up to several hundreds MGy have been demanded. Polyimide is one of a small number of the polymers which are considered to be applicable to such environment. However, actually the characteristics as the insulator for such large dose radiation environment have not been sufficiently verified. In this study, the gamma-ray of as large dose as 100 MGy was irradiated on the polyimides having different chemical structure in the air and in nitrogen, and the change of their mechanical and electrical characteristics was elucidated, at the same time, the structural change was examined. The four kinds of polyimides used for the experiment were three kinds of thermosetting type and thermoplastic polyether imide. Co-60 gamma-ray was irradiated at the dose rate of 17 kGy/h at room temperature. The tensile properties, volume resistivity, dielectric tangent, gel fraction, glass transition temperature and IR spectra were examined. In the air, the characteristics lowered by large dose irradiation due to the severance of main chains. In nitrogen, the deterioration was extremely slight, and cross-linking occurred. (K.I.)

Cesium adsorption ability and stability of metal hexacyanoferrate irradiated with gamma-rays

International Nuclear Information System (INIS)

Arisaka, Makoto; Watanabe, Masayuki; Ishizaki, Manabu; Kurihara, Masato; Chen, Rongzhi; Tanaka, Hisashi

2013-01-01

The influence of irradiation with gamma-rays to metal hexacyanoferrate (MHCF: M = Fe, Cu or Ni), which is known as an adsorbent for selective adsorption of cesium (Cs) ion in solution, on Cs adsorption ability and stability was investigated in HNO 3 solutions. Under the adsorbed dose conditions (50 - 300 kGy), it was found that the MHCF is fully stable although the radiolytic decomposition of MHCF was slightly observed with an increase of the total adsorbed dose, which was confirmed by an increment of Fe, Cu or Ni concentration in HNO 3 solution after the irradiation. The weight percent of the metal in the solution to initial weight of MHCF was less than unity. Moreover, no change in composition of carbon, hydrogen and nitrogen in MHCF was observed. On the other hand, the distribution coefficients of Cs to the irradiated MHCF were independent of the total adsorbed dose. This indicates that the Cs adsorption ability was maintained under gamma-ray irradiation. (author)

Bacteriostatic activity of various antibiotics after gamma-ray irradiation

International Nuclear Information System (INIS)

Fleurette, J.; Madier, S.; Transy, M.J.

1975-01-01

The purpose of the work described was to discover whether the antibiotics used in medicine can be sterilized by gamma rays; in this preliminary study, only the antimicrobic activity - the principal criterion for this type of medicament - was evaluated. Thirty-three products belonging to the various families of antibacterial and antifungic antibiotics were studied. The substances were irradiated in the dry state and in an aqueous solution, using a caesium-137 irradiator. The antibacterial and antifungic activity before and after irradiation was investigated by the method of diffusion in gelose. When irradiated in the dry state, 14 antibiotics preserve normal activity up to a dose of 10 Mrad; at doses between 5 and 10 Mrad, 15 other antibiotics are subject to a variable, but moderate, loss activity; and four register a slight loss of activity at a dose of 2.5 Mrad. In an aqueous solution all but two of the antibiotics suffer total loss of activity at a dose of 2.5 Mrad. As most commercial antibiotics are supplied in the dry state, gamma irradiation may be a useful sterilization process. However, preparations such as eye lotions, suspensions, ointments, etc. should be excepted

Effect of gamma ray irradiation on seed germination of Ardisia crenata

International Nuclear Information System (INIS)

Huang Donghua; Xu Hong; Huang Yanping; Song Xiaomin

2011-01-01

The seeds of Ardisia crenata were used as experimental material and treated with gamma ray under the irradiative doses ranging from 50 to 500 Gy. The results showed that the seed germination rates were not affected under the irradiative dose of 150 Gy and below. The germination potentiality turned to reduce while the irradiative dose was higher than 250 Gy. And in the range of 300 to 500 Gy the germination rates were decreased with the increase of the irradiative dose. (authors)

Removal of endocrine disruptors PAEs in drinking water by gamma-ray irradiation

International Nuclear Information System (INIS)

Zhao Yongfu; Zheng Zheng; Zheng Binguo; Wang Changbao; Li Lili

2012-01-01

Phthalic acid esters (PAEs) belong to environmental endocrine disruptor. The dimethyl phthalate (DMP), diethyl phthalate (DEP) and di-n-butyl phthalate (DBP) were selected for the radiation study. The removal efficiencies of DMP, DEP and DBP in drinking water by gamma-ray irradiation are discussed. The results show that these PAEs could be efficiently removed by gamma-ray irradiation. The removal efficiencies of DMP, DEP and DBP (12 mg/L) in aqueous solutions by 0.8 kGy gamma-ray treatment were 96.6%, 94.5% and 86.2%. The absorbed dose needed for the removal of total carbon in aqueous solutions was much larger than the doses for PAEs degradation. When 2 kGy was selected, the removal efficiencies of TC for DMP, DEP and DBP were only 23.6%, 14.3% and 12.9%. The study results also show that the radiation degradation reaction of PAEs should be divided into two stages: low dose addition reaction and high dose ring-opening reaction. This study is of significance in the disposal of micro-polluted drinking water. (authors)

Sterilization of commercial spices by gamma-ray irradiation and its effect to essencial oil

International Nuclear Information System (INIS)

Tajima, Makoto; Hossain, Tarib.

1989-01-01

Eleven kinds of commercial spices were irradiated with gamma-ray at the dose of 0 to 5 kGy. The microbial counts of almost all the samples were decreased under 10 3 /g by the dose of 5 kGy. The D 10 value of microbials contaminated to these spices were 1.1 to 4.3. Five kGy of gamma-ray irradiation affected to the recoveries of essencial oil from the spices. The effect was varied between spices. While the recoveries from some spices were increased, the others were decreased. (author)

Sterilization of commercial spices by gamma-ray irradiation and its effect to essencial oil

Energy Technology Data Exchange (ETDEWEB)

Tajima, Makoto (National Food Research Inst., Tsukuba, Ibaraki (Japan)); Hossain, Tarib

1989-11-01

Eleven kinds of commercial spices were irradiated with gamma-ray at the dose of 0 to 5 kGy. The microbial counts of almost all the samples were decreased under 10{sup 3}/g by the dose of 5 kGy. The D{sub 10} value of microbials contaminated to these spices were 1.1 to 4.3. Five kGy of gamma-ray irradiation affected to the recoveries of essencial oil from the spices. The effect was varied between spices. While the recoveries from some spices were increased, the others were decreased. (author).

EFFECT OF GAMMA RAY IRRADIATION ON INTERLAMINAR SHEAR STRENGTH OF GLASS FIBER REINFORCED PLASTICS AT 77 K

International Nuclear Information System (INIS)

Nishimura, A.; Nishijima, S.; Izumi, Y.

2008-01-01

It is known that an organic material is damaged by gamma ray irradiation, and the strength after irradiation has dependence on the gamma ray dose. These issues are important not only to make global understanding of electric insulating performance of glass fiber reinforced plastics (GFRP) under irradiation condition but also to develop new insulation materials. This paper presents the dependence of fracture mode and interlaminar shear strength (ILSS) on the material and the gamma ray irradiation effect on the fracture mode and the ILSS. 6 mm radius loading nose and supports were used to prompt ILS fracture for a short beam test. A 2.5 mm thick small specimen machined out of a 13 mm thick G-10CR GFRP plate (sliced specimen) showed lower ILSS and translaminar shear (TLS) fracture, although the same size specimen prepared from a 2.5 mm G-10CR GFRP plate (non-sliced specimen) showed ILS fracture and the higher ILSS. Both type of specimens showed the degradation of ILSS after gamma ray irradiation. The fracture mode of the non-sliced specimen changed from ILS to TLS fracture and no bending fracture was observed. The resistance to shear deformation of glass cloth/epoxy laminate structure would be damaged by the irradiation

A Performance Evaluation of a Notebook PC under a High Dose-Rate Gamma Ray Irradiation Test

Directory of Open Access Journals (Sweden)

Jai Wan Cho

2014-01-01

Full Text Available We describe the performance of a notebook PC under a high dose-rate gamma ray irradiation test. A notebook PC, which is small and light weight, is generally used as the control unit of a robot system and loaded onto the robot body. Using TEPCO’s CAMS (containment atmospheric monitoring system data, the gamma ray dose rate before and after a hydrogen explosion in reactor units 1–3 of the Fukushima nuclear power plant was more than 150 Gy/h. To use a notebook PC as the control unit of a robot system entering a reactor building to mitigate the severe accident situation of a nuclear power plant, the performance of the notebook PC under such intense gamma-irradiation fields should be evaluated. Under a similar dose-rate (150 Gy/h gamma ray environment, the performances of different notebook PCs were evaluated. In addition, a simple method for a performance evaluation of a notebook PC under a high dose-rate gamma ray irradiation test is proposed. Three notebook PCs were tested to verify the method proposed in this paper.

The effect of red ginseng extract on superoxide dismutase activity in the kidney of gamma-ray irradiated mice

International Nuclear Information System (INIS)

Park, Yong Soon

1992-01-01

This study was prepared to observe the change of enzyme activities in kidney treated with red ginseng extract in the gamma ray irradiated mice. Determine the activity of SOD, peroxidase, catalase in the kidney a period of 1 day, 2 day, 3 day, 4 day, 5 day after a saline injection or injection of red ginseng extract or gamma ray irradiated group into four classify. The activity SOD and catalase showed a tendency to increase and recovery at the early state but pay no regard. Where ase, the activity of peroxide restored and increased pay regard. A physiological saline injection group after gamma ray irradiation showed a tendency to diminish after remarkable increase of activity of SOD, peroxidase and catalase than control group. Injection group of red ginseng extract after gamma ray irradiation observed rapid recovery on activity of SOD, peroxidase, catalase than a saline injection group. Experimental result suggested that injection of red ginseng extract after irradiation have the recovery effect on the changed of activity of SOD, peroxidase and catalase against radiation injury

Digested livestock wastewater treatment using gamma-ray irradiation and struvite crystallization

International Nuclear Information System (INIS)

Kim, Tak Hyun; Lee, Sang Ryul; Nam, Youn Ku; Lee, Myun Joo

2009-01-01

Livestock wastewater generally contains high strength of organics (COD), ammonia nitrogen (NH 4 + -N), phosphate phosphorus (PO 4 3- -P) and suspended solids. It is very difficult to treat by conventional wastewater treatment techniques. In this study, struvite crystallization was carried out to treat the digested livestock wastewater. 1.0 :1.2 :1.2 was determined as an optimal NH 4 + :Mg 2+ : PO 4 3- mol ratio of struvite crystallization. For the digested livestock wastewater, COD, NH 4 + -N and PO 4 3- -P removal efficiencies by struvite crystallization were 72.4%, 98.9%, and 74.8%, respectively. Gamma-ray irradiation was carried out prior to struvite crystallization of livestock wastewater. The enhancement of struvite crystallization efficiency could be obtained by the pretreatment of gamma-ray irradiation due to the decrease of COD, NH 4 + -N and PO 4 3- -P concentration

Measurement and calculation of characteristic prompt gamma ray spectra emitted during proton irradiation

Energy Technology Data Exchange (ETDEWEB)

Polf, J C; Peterson, S; Beddar, S [M D Anderson Cancer Center, Univeristy of Texas, Houston, TX 77030 (United States); McCleskey, M; Roeder, B T; Spiridon, A; Trache, L [Cyclotron Institute, Texas A and M University, College Station, TX 77843 (United States)], E-mail: jcpolf@mdanderson.org

2009-11-21

In this paper, we present results of initial measurements and calculations of prompt gamma ray spectra (produced by proton-nucleus interactions) emitted from tissue equivalent phantoms during irradiations with proton beams. Measurements of prompt gamma ray spectra were made using a high-purity germanium detector shielded either with lead (passive shielding), or a Compton suppression system (active shielding). Calculations of the spectra were performed using a model of both the passive and active shielding experimental setups developed using the Geant4 Monte Carlo toolkit. From the measured spectra it was shown that it is possible to distinguish the characteristic emission lines from the major elemental constituent atoms (C, O, Ca) in the irradiated phantoms during delivery of proton doses similar to those delivered during patient treatment. Also, the Monte Carlo spectra were found to be in very good agreement with the measured spectra providing an initial validation of our model for use in further studies of prompt gamma ray emission during proton therapy. (note)

Recycling of Gamma Irradiated Inner Tubes in Butyl Based Rubber Compound

International Nuclear Information System (INIS)

Karaagac, B.

2006-01-01

Crosslinked elastomeric materials, such as tyres are of great challenge concerning the environmental and ecological reasons. Ionizing radiation seems to offer unique opportunities to tackle the problem of recycling of polymers and rubbers on account of its ability to cause chain scission and/or cross-linking of polymeric materials. There is only limited amount of work reported on the irradiation-induced degradation of rubbers. Unlike the majority of the elastomers with high levels of unsaturation, butyl rubber exhibits significant degradation by ionizing radiation action. In this study, recycling of gamma irradiated inner tubes made of butyl rubber in butyl based rubber compounds was studied. Used inner tubes were irradiated with gamma rays in air at 100 and 120 kGy absorbed doses. The compatibility of irradiated inner tubes with virgin butyl rubber was first investigated. Gamma irradiated inner tube wastes were replaced with butyl rubber up to 15 phr in the compound recipe. Similar recipes were also prepared by using the same quantity of commercial butyl rubber crumbs devulcanized by conventional methods. The rheological and mechanical properties and carbon black dispersion degree for both types of compounds prepared by using inner tubes scraps and commercial butyl crumbs were measured and were compared to the values of virgin butyl rubber compound. It is well known that mechanical properties are deteriorated when rubber crumb is added to the virgin compound. It was observed that the decrease in the mechanical properties was much lower for the compounds prepared from the tubes irradiated at 120 kGy than irradiated at 100 kGy. The better mechanical properties were obtained for the compounds prepared by recycling of irradiated inner tubes at 120 kGy than the compounds prepared by using commercial butyl crumbs. Almost similar carbon black distributions were observed for the all compounds studied. It has been concluded that gamma irradiated inner tubes are compatible

Evaluation of skyshine dose due to gamma-rays from a cobalt-60 irradiation facility

International Nuclear Information System (INIS)

Kanazawa, Tamotsu; Okamoto, Shinichi; Ohnishi, Tokuhiro; Tsujii, Yukio

1991-01-01

We attempted to evaluate skyshine dose due to gamma-rays from a cobalt-60 irradiation facility. As the first step, the results of measurements and calculations were compared of the skyshine dose due to gamma-rays from the cobalt-60 source of 1.45 PBq set in the No.4 irradiation room of our laboratory. Distances of measuring points from the cobalt source were in the range from 17 m to about 100 m in the site of our office. Calculation was carried out with simplified single scattering method. The calculated values of the skyshine dose were higher than the measured values. For more precise evaluation of the skyshine dose, the following factors are to be considered; the dose rate distribution on the roof above the source and the attenuation of gamma-rays by air. (author)

Influence of gamma irradiation on mechanical and thermal properties of waste polyethylene/nitrile butadiene rubber blend

Directory of Open Access Journals (Sweden)

Raouf O. Aly

2016-11-01

Full Text Available Gamma irradiation radical–radical interaction crosslinking of elastomers and thermoplastic is a special type of crosslinking technique that has gained importance over conventional chemical crosslinking method as process is fast, pollution free, and simple. In this work a blend polymer, based on waste polyethylene and nitrile butadiene rubber, has been irradiated with gamma-rays, mechanically and thermally investigated at varying NBR content. FTIR and SEM techniques were used in addition to the swelling behavior to emphasize the blend formation. Mechanical properties like tensile strength, elongation at break and modulus at different elongations were studied and compared with those of unirradiated ones. A relatively low-radiation dose was found effective in improving the level of mechanical properties. Differential scanning calorimeter and thermogravimetric analysis were used to study the thermal characteristics of the irradiated polymer. Enhancement in thermal stability has been observed for higher NBR containing blends and via radiation-induced crosslinking up to ≈50 kGy.

Study of uptake and endocytosis of gamma rays-irradiated crotoxin by mice peritoneal macrophages

International Nuclear Information System (INIS)

Cardi, Bruno Andrade

1999-01-01

The purpose was to investigate the uptake and endocytosis of 2000 Gy 60 Co irradiated crotoxin through mouse peritoneal macrophages, correlating with native one and another non related protein, the ovalbumin. Native (CTXN) or 2000 Gy 60 Co γ-rays (dose rate 540 Gy/hour) irradiated crotoxin (CTXI) or ovalbumin processed of same manner (OVAN - OVAI) were offered to mouse peritoneal macrophages and their uptake was evaluated by immunohistochemistry and quantitative in situ ELISA. The involvement of scavenger receptors (ScvR) was evaluated by using blockers drugs (Probuco-PBC or Dextran Sulfate - SD) or with nonspecific blocking using fetal calf serum (FBS). The morphology and viability of macrophages were preserved during the experiments. CTXI showed irradiation-induced aggregates and formation of oxidative changing were observed on this protein after gamma rays treatment. By immunohistochemistry we could observe heavy stained phagocytic vacuole on macrophages incubated with CTXI, as compared with CTXN. Quantitatively by in situ ELISA, the sema pattern was observed, displaying a 2-fold CTXI incorporation. In presence of PBC or SD we could find a significant decrease of CTXI uptake but not of CTXN. However the CTXN uptake was depressed by FBS, not observed with CTXI. OVA, after gamma rays treatment, underwent a high degradation suffering a potent incorporation and metabolism by macrophages, with a major uptake of OVAI in longer incubation (120 minutes). Gamma rays ( 60 Co) produced oxidative changes on CTX molecule, leading to a uptake by ScvR-mice peritoneal macrophages, suggesting that the relation antigen-presenting cells and gamma rays-modified proteins are responsible for the better immune response presented by irradiated antigens. (author)

A commercial gamma-ray irradiation plant in Japan

International Nuclear Information System (INIS)

Tomita, K.; Sugimoto, S.

1977-01-01

In 1973, a commercial gamma-ray irradiation plant was constructed in Takasaki, about 100 km north of Tokyo. The plant has been used for both production of irradiated commercial products and irradiation services. The irradiation services are being made available for sterilization of both medical appliances such as disposable medical syringes, catheters, surgical sutures, and sterilization of feed stuffs for animals. Treatment of plastic materials and colouring of both crystals and glass wares are also undertaken. This facility can accommodate 600 kCi of 60 Co and has a monthly treating capacity of 12,000 packages ( a standard carton of 340 mm x 400 mm x 500 mm) at an irradiation dose of 1 Mrad/hr. A receiving port for packages is on the second floor and the outlet of the irradiated packages on the first floor, with three lines of connecting loop conveyors between them, and the irradiation compartment in the center section. The space arrangement of the facility is well designed and gravity can be utilized for the transportation of the packages. Polymer impregnated coral is put on the market for ornamental building material on an order contract basis. (author)

Gamma-ray irradiation and post-irradiation at room and elevated temperature response of pMOS dosimeters with thick gate oxides

Directory of Open Access Journals (Sweden)

Pejović Momčilo M.

2011-01-01

Full Text Available Gamma-ray irradiation and post-irradiation response at room and elevated temperature have been studied for radiation sensitive pMOS transistors with gate oxide thickness of 100 and 400 nm, respectively. Their response was followed based on the changes in the threshold voltage shift which was estimated on the basis of transfer characteristics in saturation. The presence of radiation-induced fixed oxide traps and switching traps - which lead to a change in the threshold voltage - was estimated from the sub-threshold I-V curves, using the midgap technique. It was shown that fixed oxide traps have a dominant influence on the change in the threshold voltage shift during gamma-ray irradiation and annealing.

Influence of UV Photo-Transfer on Post Irradiated Double Sulphate Poly-Crystals By Gamma And X-rays

International Nuclear Information System (INIS)

El-kolaly, M.A.

2000-01-01

Solid state thermoluminescence (TL) dosimetry has for many years been the pre-eminent method for quantifying ionizing radiation dose. In this work, thermoluminescence characteristics of the double sulphate (Li Cs So 4 ) poly-crystals have been studied after exposure to different doses from X and gamma radiation. The glue curves showed TL response of three peaks at 75,125,250 degree. The structure of the glue peaks due to X-rays is quite different from that due to gamma rays. UV exposure yields a regeneration of the TL peaks for the post irradiated samples for X or gamma radiation with some changes in the peaks structure especially the third peak. For the post X-ray irradiated crystals, the area under the third glow peak (III) increased linearly with the integrated time of UV exposures till about 30 min. after which no changes were observed; while , for the post gamma-irradiated crystals two linear regions were observed

Radiation-induced reduction of diuron by gamma-ray irradiation

International Nuclear Information System (INIS)

Zhang Jibiao; Zheng Zheng; Zhao Tan; Zhao Yongfu; Wang Lianhong; Zhong Yun; Xu Yue

2008-01-01

Diuron degradation efficiencies and the proposed mechanism by gamma-ray irradiation were investigated. Several factors that might affect the degradation values were further examined. The UV absorbances at 200-400 nm and diuron concentration decreased with the increase of radiation dose. When diuron initial concentration was 18.5 mg L -1 and 1.0 kGy was selected as the radiation dose, diuron removal value and loss of total organic carbon were 100 and 34.1%, respectively. However, the concentration of Cl - ion increased with the increase of radiation dose. The process could be depicted by first order reaction kinetics and the reaction was mainly caused by the reaction of diuron with ·OH and e aq - . The degradation efficiency decreased with the increase of initial concentration at the same radiation dose. H 2 O 2 , HCO 3 - , NO 3 - , NO 2 - , CH 3 OH and humic acid as additives reduced the degradation efficiency. Furthermore, the increase of NO 3 - , NO 2 - , CH 3 OH and humic acid would result in the decrease of the degradation values. The pH value could affect the removal efficiency and the degradation process was enhanced in acid condition. The pH value became lower with increasing radiation dose after gamma-ray irradiation

Effects of gamma-ray irradiation on the optical properties of amorphous Se100-xHgx thin films

Science.gov (United States)

Ahmad, Shabir; Islam, Shama; Nasir, Mohd.; Asokan, K.; Zulfequar, M.

2018-06-01

In this study, the thermal quenching technique was employed to prepare bulk samples of Se100-xHgx (x = 0, 5, 10, 15). Thin films with a thickness of ∼250 nm were deposited on glass substrates using the thermal evaporation technique. These films were irradiated with gamma rays at doses of 25-100 kGy. The elemental compositions of the as-deposited thin films were confirmed by energy dispersive X-ray analysis and Rutherford backscattering spectrometry. X-ray diffraction analysis confirmed the crystalline nature of these thin films upto the dose of 75 kGy. Fourier transform-infrared spectroscopy showed that the concentration of defects decreased after gamma irradiation. Microstructural analysis by field emission scanning electron microscopy indicated that the grain size increases after irradiation. Optical study based on spectrophotometry showed that the optical band gap values of these films increase after the addition of Hg whereas they decrease after gamma irradiation. We found that the absorption coefficient increases with doses up to 75 kGy but decreases at higher doses. These remarkable shifts in the optical band gap and absorption coefficient values are interpreted in terms of the creation and annihilation of defects, which are the main effects produced by gamma irradiation.

The influence of irradiation of gamma-rays on the pulping and paper making, (4)

International Nuclear Information System (INIS)

Suzuki, Kyoji; Inoue, Kaoru; Hanamura, Norio; Mori, Kenji

1980-01-01

The influence of gamma-irradiation on the beating properties of unbleached kraft pulps was studied, and the changes of the mechanical and chemical properties of the sheet made from those pulps were also investigated. The results obtained were as follows: (1) When the unbeaten pulp was treated with gamma-ray, the degree of polymerization of cellulose was decreased rapidly and the formation of aldehyde and carboxyl groups in pulp was observed in addition to that the beating time of irradiated pulps was reduced comparing with non-irradiated pulp. These effects increased roughly in proportion to the radiation dose. (2) Gamma-irradiation was more effective in wet state (moisture content = 70 - 80%) than air dry state. This may be due to the degradation products of water by gamma-irradiation. (3) The mechanical properties (breaking length, tear and burst factors) of the sheets made from irradiated pulps were considerably deteriorated at 10 7 R, but there was a slight deterioration up to 10 6 R. (4) Comparing the result of the mechanical properties, the strengths of the various sheets were shown in the following order: the sheet irradiated after paper making gt the sheet irradiated before beating (air dry state) gt the sheet irradiated before beating (wet state). (author)

Influence of the molecular modifications on the properties of EPDM elastomers under irradiation

Energy Technology Data Exchange (ETDEWEB)

Davenas, J. E-mail: joel.davenas@univ-lyon1.fr; Stevenson, I.; Celette, N.; Vigier, G.; David, L

2003-08-01

The degradation of the mechanical behaviour of EPDM elastomers used as cable insulation materials has been investigated by mechanical spectroscopy and tensile tests for different formulations: unvulcanised EPDM, vulcanised and stabilised elastomer with an antioxidant. In all cases, {gamma}-irradiation of EPDM under oxygen leads to a reduction of the molecular mobility indicated by the shift of the glass transition relaxation temperature towards higher temperatures. Moreover, the molecular flow occurring above T{sub g} is suppressed after irradiation for the unvulcanised EPDM providing evidence of cross-linking. The competition between cross-linking and chain scissions is shown by the decrease of the storage modulus above the crystallites melting temperature ({approx}40 deg. C) at doses larger than 100 kGy. A strong increase of the Young modulus and reduction of the elongation at break of the non-vulcanised EPDM becoming more brittle are shown by stress/strain characterisations performed at 80 deg. C. At the opposite vulcanised EPDM exhibits higher elongation at break after crystallites melting. This evolution is interpreted by the competition between cross-linking and chain scissions, being hindered by the crystallites at room temperature. The intrinsic irradiation effects can be isolated after crystallite melting. The reduction of the molecular mobility can be explained by a chemi-crystallisation process assisted by chain scissions, leading to a more rigid phase upon irradiation.

Functionalization and magnetization of carbon nanotubes using Co-60 gamma-ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Chen, C.Y.; Fu, M.J.; Tsai, C.Y. [Division of Isotope Application, Institute of Nuclear Energy Research, Atomic Energy Council, P.O. BOX 3-27 Longtan, Taoyuan County 32546, Taiwan (R.O.C.) (China); Lin, F.H. [Institute of Biomedical Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (R.O.C.) (China); Chen, K.Y., E-mail: chenky@iner.gov.tw [Division of Isotope Application, Institute of Nuclear Energy Research, Atomic Energy Council, P.O. BOX 3-27 Longtan, Taoyuan County 32546, Taiwan (R.O.C.) (China)

2014-10-01

Functionalized magnetic carbon nanotubes (CNTs) can be used in the biological and biomedical fields as biosensors, drug delivery systems, etc., which makes research into processes for manufacturing modified CNTs quite important. In this paper, Co-60 gamma irradiation is shown to be an effective tool for fabricating functionalized and magnetized CNTs. After the Co-60 gamma irradiation, the presence of carboxylic functional groups on the CNT walls was confirmed by their Fourier transform infrared spectra, and the presence of Fe{sub 3}O{sub 4} was verified by the X-ray diffraction patterns. The functionalized and magnetized CNTs produced using Co-60 gamma irradiation have excellent dispersion properties. The techniques for functionalizing and magnetizing CNTs are introduced in this paper, and applications of the modified CNTs will be reported after more data are gathered. - Highlights: Dispersion ability of carbon nanotubes (CNTs) was improved by functionalization. CNTs were easily manipulated by precipitation of magnetic nanoparticles. Our product can be used as versatile biosensor substrate for biomarker screening.

The role of {sup 60}Co gamma-ray irradiation on the interface states and series resistance in MIS structures

Energy Technology Data Exchange (ETDEWEB)

Tascioglu, Ilke [Department of Physics, Faculty of Science and Arts, Gazi University, 06500 Ankara (Turkey); Tataroglu, Adem, E-mail: ademt@gazi.edu.t [Department of Physics, Faculty of Science and Arts, Gazi University, 06500 Ankara (Turkey); Ozbay, Akif; Altindal, Semsettin [Department of Physics, Faculty of Science and Arts, Gazi University, 06500 Ankara (Turkey)

2010-04-15

The effect of gamma-ray exposure on the metal-insulator-semiconductor (MIS) structures has been investigated using the electrical characteristics at room temperature. The MIS structures are irradiated with {sup 60}Co gamma-ray source. The energy distribution of interface states was determined from the forward bias I-V characteristics by taking into account the bias dependence of the effective barrier height and ideality factor. The value of series resistance decreases with increasing dose. Experimental results confirmed that gamma-ray irradiation have a significant effect on electrical characteristics of MIS structures.

Accumulation and dissipation of positive charges induced on a PMMA build-up cap of an ionisation chamber by 60Co gamma-ray irradiation

International Nuclear Information System (INIS)

Morishita, Y.; Takata, N.

2013-01-01

The signal current from an ionisation chamber with a PMMA build-up cap decreases with irradiation time due to electric fields produced by positive charges induced on the cap. In the present study, it was confirmed that the signal current decreases faster for irradiation using narrower 60 Co gamma-ray beams. This is because the number of secondary electrons that are emitted from surrounding materials and penetrate the build-up cap is smaller in a narrower gamma-ray beam, so that fewer positive charges are neutralised. The ionisation chamber was first subjected to continuous gamma-ray irradiation for 24 h, following which it was irradiated with shorter periodic gamma-ray bursts while measuring the current signal. This allowed the coefficients of positive charge accumulation and dissipation to be determined. It was found that the dissipation coefficient has a large constant value during gamma-ray irradiation and decreases asymptotically to a small value after irradiation is stopped. From the coefficients, the minimum signal current was calculated, which is the value when accumulation and dissipation balance each other under continuous irradiation. The time required for the signal current to recover following irradiation was also calculated. (authors)

Influence of Gamma-Ray Irradiation on Absorption and Fluorescent Spectra of Nd:YAG and Yb:YAG Laser Crystals

Institute of Scientific and Technical Information of China (English)

SUN Dun-Lu; ZHANG Qing-Li; XIAO Jing-Zhong; LUO Jian-Qiao; JIANG Hai-He; YIN Shao-Tang

2008-01-01

We investigate the influence of gamma-ray irradiation on the absorption and fluorescent spectra of Nd3+ : Y3Al5O12 (Nd:YAG) and Yb3+ :Y3Al5O12 (Yb:YAG) crystals grown by the Czochralski method. Two additional absorption (AA) bands induced by gamma-ray irradiation appear at 255nm and 340nm. The former is eontributed due to Fe3+ impurity, the latter is due to Fe2+ ions and F-type colour centres. The intensity of the excitation and emission spectra as well as the fluorescent lifetime of Nd:YAG crystal decrease after the irradiation of 100 Mrad gamma-ray. In contrast, the same dose irradiation does not impair the fluorescent properties of Yb: YA G crystal. These results indicate that Yb: YA G crystal possesses the advantage over Nd: YA G crystal that has better reliability for applications in harsh radiant environment.

Gamma ray irradiation to roots of tea-plants and induced mutant system

International Nuclear Information System (INIS)

Takeda, Yoshiyuki; Nekaku, Koji; Wada, Mitsumasa

1990-01-01

In order to utilize the useful mutation which is induced by irradiation for the breeding of tea-plants, the gamma-ray irradiation to the roots of tea-plants was carried out. The samples were the roots of tea-plants of four varieties dug up in February, 1984, and were adjusted to about 20 cm, then, put in the cold storage at 5degC for 9 months till the time of irradiation in November, 1984. However, a part of them was taken out in August, and planted in a field for 76 days to germinate, thereafter, used as the samples. The gamma-ray from a Co-60 source was irradiated in the radiation breeding laboratory of Agriculture Bioresources Research Institute at the total dose of 1, 2 and 3 kR and the dose rate of 500 R/h. The irradiated roots were planted as they are or in the state of being cut, and the rate of germination, the number of buds and the induced mutation were examined. Clear difference was not observed in the rate of germination and the number of buds between the irradiated samples and those without irradiation. The long roots were superior to the short roots regarding these items. The types of the induced mutation were mostly thin leaves, and also yellowing, mottling, fascination and so on occurred. The mutant system lacking trichomes on the back of new leaves is considered to be strong against tea anthracnose, and is valuable. (K.I.)

Gamma ray irradiation to roots of tea-plants and induced mutant system

Energy Technology Data Exchange (ETDEWEB)

Takeda, Yoshiyuki; Nekaku, Koji; Wada, Mitsumasa (National Research Inst. of Vegetables, Ornamental Plants and Tea, Ano, Mie (Japan))

1990-11-01

In order to utilize the useful mutation which is induced by irradiation for the breeding of tea-plants, the gamma-ray irradiation to the roots of tea-plants was carried out. The samples were the roots of tea-plants of four varieties dug up in February, 1984, and were adjusted to about 20 cm, then, put in the cold storage at 5degC for 9 months till the time of irradiation in November, 1984. However, a part of them was taken out in August, and planted in a field for 76 days to germinate, thereafter, used as the samples. The gamma-ray from a Co-60 source was irradiated in the radiation breeding laboratory of Agriculture Bioresources Research Institute at the total dose of 1, 2 and 3 kR and the dose rate of 500 R/h. The irradiated roots were planted as they are or in the state of being cut, and the rate of germination, the number of buds and the induced mutation were examined. Clear difference was not observed in the rate of germination and the number of buds between the irradiated samples and those without irradiation. The long roots were superior to the short roots regarding these items. The types of the induced mutation were mostly thin leaves, and also yellowing, mottling, fascination and so on occurred. The mutant system lacking trichomes on the back of new leaves is considered to be strong against tea anthracnose, and is valuable. (K.I.).

Thermal, tensile and rheological properties of low density polyethylene (LDPE) processed irradiated by gamma-ray

International Nuclear Information System (INIS)

Ferreto, Helio F.R.; Oliveira, Ana C.F. de; Parra, Duclerc F.; Lugao, Ademar B.

2013-01-01

The aim of this paper is to investigate structural changes of low density polyethylene (LDPE) modified by ionizing radiation (gamma rays). The gamma radiation process for modification of commercial polymers is a widely applied technique to promote new physical-chemical and mechanical properties. Gamma irradiation originates free radicals which can induce chain scission or recombination, providing its annihilation, branching or crosslinking. The samples were prepare in hydraulic press in temperature 180 deg C after was irradiated with gamma source of 60 Co at doses of 5, 10, 20, 50 or 100 kGy at a dose rate of 5 kGy/h in inert atmosphere. The changes in molecular structure of LDPE, after gamma irradiations were evaluated using thermogravimetric analysis (TGA) and tensile machine and oscillatory rheology. The results showed the variations of the properties depending on the dose at each atmosphere. (author)

A study on the effect of 60Co gamma ray irradiation on the abrasion of dental polymethylmethacrylate, (3)

International Nuclear Information System (INIS)

Kimura, Hiroshi

1981-01-01

This report intends to clarify the relationship between the total exposure dose and scratch resistance to the specimens SF, SH, MF and MH, giving coating treatments to P.M.M.A. (dental polymethylmethacrylate) and exposing to the irradiation of 60 Co gamma ray at each dose rate. And based on the results, it is intended to develop coated P.M.M.A. with excellent scratch resistance give by irradiation of radioactive ray. From this study, the following results have been obtained. Irradiation of 60 Co gamma ray would give the best results at the exposure at 1 x 10 6 R. The SF and SH specimens in wet condition exposed to 60 Co gamma ray irradiation at 1 x 10 6 R showed a quantity of abrasion of only 17% that of untreated P.M.M.A. and the barrel test revealed outstanding abrasion and scratch resistance. Abrasion and scratch resistance of coated specimens are better utilized in wet conditions performing three times better than those in dry conditions. (author)

DNA-repair after irradiation of cells with gamma-rays and neutrons

International Nuclear Information System (INIS)

Altmann, H.

1975-11-01

The structural alterations of calf thymus DNA produced by neutron or gamma irradiation were observed by absorption spectra, sedimentation rate and viscosity measurements. Mixed neutron-gamma irradiation produced fewer single and double strand breaks compared with pure gamma irradiation. RBE-values for mixed neutron-gamma radiation were less than 1, and DNA damage decreased with increasing neutron dose rate. Repair processes of DNA occuring after irradiation were measured in mouse spleen suspensions and human lymphocytes using autoradiographic methods and gradient centrifugations. The number of labelled cells was smaller after mixed neutron-gamma irradiation than after gamma irradiation. The rejoining of strand breaks in alkaline and neutral sucrose was more efficient after gamma irradiation than after mixed neutron-gamma irradiation. Finally, the effect of detergents Tween 80 and Nonident P40 on unscheduled DNA synthesis was studied by autoradiography after mixed neutron-gamma irradiation (Dn=5 krad). The results showed that the DNA synthesis was inhibited by detergent solutions of 0.002%

Allogenic bone rods with freeze drying and gamma rays irradiation for treatment of fracture

International Nuclear Information System (INIS)

Zhou Zhenbin

1999-01-01

Opened reduction and internal fixation are the usual treatment of fracture, but both methods need a second operation for removal implants. The benefits of the bone rods are that they can avoid the removement of internal fixation and will be absorbed spontaneously. The bone rods are made of allogeneic compact bones with freeze-drying and gamma rays irradiation supplied by Shanxi Provincial Tissue Bank. The purpose of this study is to evaluate allograft reaction, the stability of the internal fixation, osteoinduction in the treatment of fracture using allogeneic bone rods with freeze drying and gamma rays irradiation. From May 1997 to May 1998, fourteen cases (male 12, female 2) of treatment were reviewed. The mean age was 37.3 (21-5 1). There were 3 medial malleolus fractures, 7 tibia and fibula fractures, 1 ulna and radius fracture, 1 lateral condyle of humerus fracture. The clinical results were satisfactory. Because the strength of the bone rods are weaker than that of screws, the bone rods are only indicated in the fixation of cancellous bones fracture and unloaded bone fracture. It can be used as a supplementary fixation of loaded bone. It is not indicated for fixation of comminuted fracture. More than two bone rods may be used in the fixation of fracture in order to get stability of the fracture and decrease stress between rods which will prevent the break of the bone rods. Allogeneic bone rods with freeze-drying and gamma rays irradiation can be used as implants of non-immunogenicity. There are no allograft reactions in all cases (including fever, leukocytosis, exudation or swelling in the wound). Although plenty of experimental studies have showed that freeze drying with gamma rays irradiation (below 50 KGy) would not destroy BMP of bone allograft, but there is no osteoinduction in our cases. The healing of a fracture and bridging external callus are similar as other operations. This new technique may have the following advantages compare with the screws: 1

Twenty years research of chronic gamma-ray irradiation on seed crops

International Nuclear Information System (INIS)

Yamashita, Atsushi

1983-01-01

Twenty years of the works on the chronic gamma-ray irradiation of seed crops are summarized. Radiosensitivity and the mutation rate per unit exposure varies not only with the genetic factor but also depend on whether treatment is given to seeds or growing plants. The relation between the radiosensitivity of seeds and growing plants also varies with plant species. In Hordeum, Avena and Nicotiana, the highest mutation rate obtained by the chronic irradiation of growing plants is similar to that in seed irradiation, but in Oryza and Setalia, chronic irradiation was two to three times more effective for attaining a higher mutation rate. The mutation spectrum also varies with the mutagen, the factors modifying the effects of mutagen, and the dose of mutagen. The suitability of a particular mutagenic treatment to a species should be taken into consideration in the evaluation of mutagenic treatment. For instance, NaN 3 is highly mutagenic to barley, but less mutagenic to rice. The gene ea7 controlling the maturing earliness of barley seems to be mutable in chronic irradiation, and the mutants obtained by chronic irradiation are healthy. The author emphasized that the chronic irradiation at the gamma-field is a useful mutagenic treatment, even though some negative results have been reported in European countries. (Kaihara, S.)

Topological and morphological analysis of gamma rays irradiated chitosan-poly (vinyl alcohol) blends using atomic force microscopy

International Nuclear Information System (INIS)

Bhatt, Rinkesh; Bisen, D.S.; Bajpai, R.; Bajpai, A.K.

2017-01-01

In the present communication, binary blends of poly (vinyl alcohol) (PVA) and chitosan (CS) were prepared by solution cast method and the roughness parameters of PVA, native CS and CS-PVA blend films were determined using atomic force microscopy (AFM). Moreover, the changes in the morphology of the samples were also investigated after irradiation of gamma rays at absorbed dose of 1 Mrad and 10 Mrad for the scanning areas of 5×5 µm 2 , 10×10 µm 2 and 20×20 µm 2 . Amplitude, statistical and spatial parameters, including line, 3D and 2D image profiles of the experimental surfaces were examined and compared to un-irradiated samples. For gamma irradiated CS-PVA blends the larger waviness over the surface was found as compared to un-irradiated CS-PVA blends but the values of average roughness for both the films were found almost same. The coefficient of skewness was positive for gamma irradiated CS-PVA blends which revealed the presence of more peaks than valleys on the blend surfaces. - Highlights: • Binary polymer blends of chitosan and PVA were prepared. • Irradiation by gamma rays exhibited a significant change in surface morphology. • Various topographical and morphological parameters were investigated. • The prepared irradiated blends may find biomedical applications.

Radiation-induced reduction of diuron by gamma-ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Zhang Jibiao [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Zheng Zheng [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China)], E-mail: zzheng@nju.edu.cn; Zhao Tan [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Zhao Yongfu [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Institute of Atomic Energy, Jiangsu Academy of Agriculture Sciences, Nanjing 210014 (China); Wang Lianhong; Zhong Yun; Xu Yue [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China)

2008-03-01

Diuron degradation efficiencies and the proposed mechanism by gamma-ray irradiation were investigated. Several factors that might affect the degradation values were further examined. The UV absorbances at 200-400 nm and diuron concentration decreased with the increase of radiation dose. When diuron initial concentration was 18.5 mg L{sup -1} and 1.0 kGy was selected as the radiation dose, diuron removal value and loss of total organic carbon were 100 and 34.1%, respectively. However, the concentration of Cl{sup -} ion increased with the increase of radiation dose. The process could be depicted by first order reaction kinetics and the reaction was mainly caused by the reaction of diuron with {center_dot}OH and e{sub aq}{sup -}. The degradation efficiency decreased with the increase of initial concentration at the same radiation dose. H{sub 2}O{sub 2}, HCO{sub 3}{sup -}, NO{sub 3}{sup -}, NO{sub 2}{sup -}, CH{sub 3}OH and humic acid as additives reduced the degradation efficiency. Furthermore, the increase of NO{sub 3}{sup -}, NO{sub 2}{sup -}, CH{sub 3}OH and humic acid would result in the decrease of the degradation values. The pH value could affect the removal efficiency and the degradation process was enhanced in acid condition. The pH value became lower with increasing radiation dose after gamma-ray irradiation.

Comparison of the effect of plasma treatment and gamma ray irradiation on PS-Cu nanocomposite films surface

Science.gov (United States)

Farag, O. F.

2018-06-01

Polystyrene-copper (PS-Cu) nanocomposite films were treated with DC N2 plasma and gamma rays irradiations. The plasma treatment of PS-Cu film surface was carried out at different treatment times, gas pressure 0.4 Torr and the applied power 3.5 W. On the other hand, the treatment with gamma rays irradiation were carried out at irradiation doses 10, 30 and 50 kGy. The induced changes in surface properties of PS-Cu films were investigated with UV-viss spectroscopy, scanning electron microscopy (SEM) and FTIR spectroscopy techniques. In addition, the wettability property, surface free energy, spreading coefficient and surface roughness of the treated samples were studied by measuring the contact angle. The UV-viss spectroscopy analysis revealed that the optical band gap decreases with increasing the treatment time and the irradiation dose for plasma and gamma treatments, respectively. SEM observations showed that the particle size of copper particles was increased with increasing the treatment time and the irradiation dose, but gamma treatment changes the copper particles size from nano scale to micro scale. The contact angle measurements showing that the wettability property, surface free energy, spreading coefficient and surface roughness of the treated PS-Cu samples were increased remarkably with increasing the treatment time and the irradiation dose for plasma and gamma treatments, respectively. The contact angle, surface free energy, spreading coefficient and surface roughness of the treated PS-Cu samples are more influenced by plasma treatment than gamma treatment.

Studies of soy sauce sterilization and its special flavour improvement by gamma-ray irradiation

International Nuclear Information System (INIS)

Yang Jingtian; Jin Xinhua; Gu Guoxing; Yun Guichun

1988-01-01

Experimental studies for sterilizing 12 kinds of soy sauce with gamma-ray irradiation showed that both sterilization and improvements in flavour and quality of soy sauce were obtained simultaneously. (author)

Effects of gamma ray irradiation on the struvite crystallization of livestock wastewater

International Nuclear Information System (INIS)

Yoo, Byeong Hak; Jo, Seong Hui; Lee, Myun Joo; Kim, Tak Hyun

2010-01-01

The struvite crystallization was applied to remove NH 4 + in livestock wastewater. The ammonium ions can be very toxic to the aquatic creatures. In this experiments, the livestock wastewater from Gongju livestock wastewater treatment plant was used. The behaviors of various parameters such as pH, mole ratio of Mg 2+ : NH 4 + : PO 4 3- and reaction temperature for struvite crystallization of livestock wastewater and the effect of gamma ray irradiation were evaluated. As results, for the pH variation, the NH 4 + removal efficiency showed the highest, 88%, at pH 9 ∼ 9.25. The removal efficiency of NH 4 + , Mg 2+ and PO 4 3- was showed highest when same molar ratio of Mg 2+ and PO 4 3- were applied. The NH 4 + removal efficiency showed 82% at 7 .deg. C, and 90% at 30 .deg. C, with temperature. When the wastewater was irradiated with 20 kGy of gamma ray, NH 4 + was removed as much as 83%

Corrosion of carbon steel and low-alloy steel in diluted seawater containing hydrazine under gamma-rays irradiation

International Nuclear Information System (INIS)

Nakano, Junichi; Yamamoto, Masahiro; Tsukada, Takashi

2014-01-01

Seawater was injected into reactor cores of Units 1, 2, and 3 in the Fukushima Daiichi nuclear power station as an urgent coolant. It is considered that the injected seawater causes corrosion of steels of the reactor pressure vessel and primary containment vessel. To investigate the effects of gamma-rays irradiation on weight loss in carbon steel and low-alloy steel, corrosion tests were performed in diluted seawater at 50°C under gamma-rays irradiation. Specimens were irradiated with dose rates of 4.4 kGy/h and 0.2 kGy/h. To evaluate the effects of hydrazine (N 2 H 4 ) on the reduction of oxygen and hydrogen peroxide, N 2 H 4 was added to the diluted seawater. In the diluted seawater without N 2 H 4 , weight loss in the steels irradiated with 0.2 kGy/h was similar to that in the unirradiated steels, and weight loss in the steels irradiated with 4.4 kGy/h increased to approximate 1.7 times of those in the unirradiated steels. Weight loss in the steels irradiated in the diluted seawater containing N 2 H 4 was similar to that in the diluted seawater without N 2 H 4 . When N 2 was introduced into the gas phase in the flasks during gamma-rays irradiation, weight loss in the steels decreased. (author)

Hydrogen release from irradiated elastomers measured by Nuclear Reaction Analysis

Energy Technology Data Exchange (ETDEWEB)

Jagielski, J., E-mail: jacek.jagielski@itme.edu.pl [Institute for Electronic Materials Technology, Wolczynska 133, 01-926 Warszawa (Poland); National Centre for Nuclear Research, A. Soltana 7, 05-400 Swierk/Otwock (Poland); Ostaszewska, U. [Institute for Engineering of Polymer Materials & Dyes, Division of Elastomers & Rubber Technology, Harcerska 30, 05-820 Piastow (Poland); Bielinski, D.M. [Technical University of Lodz, Institute of Polymer & Dye Technology, Stefanowskiego 12/16, 90-924 Lodz (Poland); Grambole, D. [Institute of Ion Beam Physics and Materials Research, Helmholtz Zentrum Dresden Rossendorf, PO Box 51 01 19, D-01314 Dresden (Germany); Romaniec, M.; Jozwik, I.; Kozinski, R. [Institute for Electronic Materials Technology, Wolczynska 133, 01-926 Warszawa (Poland); Kosinska, A. [National Centre for Nuclear Research, A. Soltana 7, 05-400 Swierk/Otwock (Poland)

2016-03-15

Ion irradiation appears as an interesting method of modification of elastomers, especially friction and wear properties. Main structural effect caused by heavy ions is a massive loss of hydrogen from the surface layer leading to its smoothening and shrinking. The paper presents the results of hydrogen release from various elastomers upon irradiation with H{sup +}, He{sup +} and Ar{sup +} studied by using Nuclear Reaction Analysis (NRA) method. The analysis of the experimental data indicates that the hydrogen release is controlled by inelastic collisions between ions and target electrons. The last part of the study was focused on preliminary analysis of mechanical properties of irradiated rubbers.

Freshly induced short-lived gamma-ray activity as a measure of fission rates in lightly re-irradiated spent fuel

Energy Technology Data Exchange (ETDEWEB)

Kroehnert, H., E-mail: hanna.kroehnert@psi.c [Paul Scherrer Institut (PSI), OPRA-E07, CH-5232 Villigen (Switzerland); Perret, G., E-mail: gregory.perret@psi.c [Paul Scherrer Institut (PSI), OPRA-E07, CH-5232 Villigen (Switzerland); Murphy, M.F., E-mail: mike.murphy@psi.c [Paul Scherrer Institut (PSI), OPRA-E07, CH-5232 Villigen (Switzerland); Chawla, R., E-mail: rakesh.chawla@epfl.c [Paul Scherrer Institut (PSI), OPRA-E07, CH-5232 Villigen (Switzerland); Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

2010-12-01

A new measurement technique has been developed to determine fission rates in burnt fuel, following re-irradiation in a zero-power research reactor. The development has been made in the frame of the LIFE-PROTEUS program at the Paul Scherrer Institute, which aims at characterizing the interfaces between fresh and highly burnt fuel assemblies in modern LWRs. To discriminate against the high intrinsic gamma-ray activity of the burnt fuel, the proposed measurement technique uses high-energy gamma-rays, above 2000 keV, emitted by short-lived fission products freshly produced in the fuel. To demonstrate the feasibility of this technique, a fresh UO{sub 2} sample and a 36 GWd/t burnt UO{sub 2} sample were irradiated in the PROTEUS reactor and their gamma-ray activities were recorded directly after irradiation. For both fresh and the burnt fuel samples, relative fission rates were derived for different core positions, based on the short-lived {sup 142}La (2542 keV), {sup 89}Rb (2570 keV), {sup 138}Cs (2640 keV) and {sup 95}Y (3576 keV) gamma-ray lines. Uncertainties on the inter-position fission rate ratios were mainly due to the uncertainties on the net-area of the gamma-ray peaks and were about 1-3% for the fresh sample, and 3-6% for the burnt one. Thus, for the first time, it has been shown that the short-lived gamma-ray activity, induced in burnt fuel by irradiation in a zero-power reactor, can be used as a quantitative measure of the fission rate. For both fresh and burnt fuel, the measured results agreed, within the uncertainties, with Monte Carlo (MCNPX) predictions.

[Induction of glutathione and activation of immune functions by low-dose, whole-body irradiation with gamma-rays].

Science.gov (United States)

Kojima, Shuji

2006-10-01

We first examined the relation between the induction of glutathione and immune functions in mice after low-dose gamma-ray irradiation. Thereafter, inhibition of tumor growth by radiation was confirmed in Ehrlich solid tumor (EST)-bearing mice. The total glutathione level of the splenocytes transiently increased soon after irradiation and reached a maximum at around 4 h postirradiation. Thereafter, the level reverted to the 0 h value by 24 h postirradiation. A significantly high splenocyte proliferative response was also recognized 4 h postirradiation. Natural killer (NK) activity was also increased significantly in a similar manner. The time at which the response reached the maximum coincided well with that of maximum total glutathione levels of the splenocytes in the gamma-ray-irradiated mice. Reduced glutathione exogenously added to splenocytes obtained from normal mice enhanced the proliferative response and NK activity in a dose-dependent manner. The inhibitory effects of radiation on tumor growth was then examined in EST-bearing mice. Repeated low-dose irradiation (0.5 Gy, four times, before and within an early time after inoculation) significantly delayed the tumor growth. Finally, the effect of single low-dose (0.5 Gy), whole-body gamma-ray irradiation on immune balance was examined to elucidate the mechanism underlying the antitumor immunity. The percentage of B cells in blood lymphocytes was selectively decreased after radiation, concomitant with an increase in that of the helper T cell population. The IFN-gamma level in splenocyte culture prepared from EST-bearing mice was significantly increased 48 h after radiation, although the level of IL-4 was unchanged. IL-12 secretion from macrophages was also enhanced by radiation. These results suggest that low-dose gamma-rays induce Th1 polarization and enhance the activities of tumoricidal effector cells, leading to an inhibition of tumor growth.

DNA microarray analyses reveal a post-irradiation differential time-dependent gene expression profile in yeast cells exposed to X-rays and gamma-rays.

Science.gov (United States)

Kimura, Shinzo; Ishidou, Emi; Kurita, Sakiko; Suzuki, Yoshiteru; Shibato, Junko; Rakwal, Randeep; Iwahashi, Hitoshi

2006-07-21

Ionizing radiation (IR) is the most enigmatic of genotoxic stress inducers in our environment that has been around from the eons of time. IR is generally considered harmful, and has been the subject of numerous studies, mostly looking at the DNA damaging effects in cells and the repair mechanisms therein. Moreover, few studies have focused on large-scale identification of cellular responses to IR, and to this end, we describe here an initial study on the transcriptional responses of the unicellular genome model, yeast (Saccharomyces cerevisiae strain S288C), by cDNA microarray. The effect of two different IR, X-rays, and gamma (gamma)-rays, was investigated by irradiating the yeast cells cultured in YPD medium with 50 Gy doses of X- and gamma-rays, followed by resuspension of the cells in YPD for time-course experiments. The samples were collected for microarray analysis at 20, 40, and 80 min after irradiation. Microarray analysis revealed a time-course transcriptional profile of changed gene expressions. Up-regulated genes belonged to the functional categories mainly related to cell cycle and DNA processing, cell rescue defense and virulence, protein and cell fate, and metabolism (X- and gamma-rays). Similarly, for X- and gamma-rays, the down-regulated genes belonged to mostly transcription and protein synthesis, cell cycle and DNA processing, control of cellular organization, cell fate, and C-compound and carbohydrate metabolism categories, respectively. This study provides for the first time a snapshot of the genome-wide mRNA expression profiles in X- and gamma-ray post-irradiated yeast cells and comparatively interprets/discusses the changed gene functional categories as effects of these two radiations vis-à-vis their energy levels.

Effects of gamma ray and electron-beam irradiations on survival of anaerobic and facultatively anaerobic bacteria

International Nuclear Information System (INIS)

Miyahara, Michiko; Miyahara, Makoto

2002-01-01

An extension of the approval for food irradiation is desired due to the increase in the incidence of food poisoning in the world. One anaerobic (Clostridium perfringens) and four facultatively anaerobic (Bacillus cereus, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella Enteritidis) bacteria irradiated with gamma ray or electron beam (E-beam) were tested in terms of survival on agar under packaging atmosphere. Using pouch pack, effects of two irradiations on survival of anaerobic and facultatively anaerobic bacteria were evaluated comparatively. E-beam irradiation was more effective than gamma ray irradiation in decreasing the lethal dose 10% (D 10 ) value of B. cereus at 4 deg C, slightly more effective in that of E. coli O157, and similarly effective in that of the other three bacteria at 4 deg C. The gamma irradiation of the bacteria without incubation at 4 deg C before irradiation was more effective than that of the bacteria with incubation overnight at 4 deg C before irradiation in decreasing the D10 values of these bacteria (B. cereus, E. coli O157, and L. monocytogenes). Furthermore, ground beef patties inoculated with bacteria were irradiated with 1 kGy by E-beam (5 MeV) at 4 deg C. The inoculated bacteria in the 1-9 mm beef patties were killed by 1 kGy E-beam irradiation and some bacteria in more than 9 mm beef patties were not killed by the irradiation. (author)

Grafting study of polysulfone polymeric membranes by gamma ray irradiation

International Nuclear Information System (INIS)

Furtado Filho, Acacio A.M.; Gomes, Ailton de S.

2011-01-01

Radiation-induced grafting of styrene poli sulfone films were investigated by simultaneous method in solution using gamma-ray from a radio nuclide 60 Co source. The gamma-ray energy of high intensity induced breaking of chemical bonds leading to free radical formation. The radical start a conventional polymerization sequence comparable with that obtained with a chemical catalyst acting as initiator. The effects of grafting conditions such as irradiation total dose, dose rate and addition of cross linking agent, were studied by means of morphology analysis, thermal degradation and crystallinity. After the grafting reaction, the membranes were submitted to an exhaustive extraction with solvent to remove the polystyrene homopolymer formed. The degree of grafting (DOG) was analyzed by percentage of weight increase. As a result, the reaction always follows the same pattern: DOG increases rapidly initially whilst propagation is the main reaction, then more slowly as termination becomes more frequent. (author)

Effects of gamma ray irradiation on early growth of soybean (Glycine mac (L). Merrill)

International Nuclear Information System (INIS)

Lilik Harsanti; Yulidar

2015-01-01

Increase my in domestic soybean production is one of the government's program to reduce dependence on imported soybeans and soybean efforts to achieve self-sufficiency in 2015. An experiment has been conducted to study the effects of gamma ray irradiation of of 60 Cobalt on early growth of soybean seed. Variety Denna 2 varieties have been irradiated by gamma rays with 0 Gy, 200 Gy, 300 Gy, 400 Gy doses, and then planted in green house on Ps Jumat PAIR-BATAN. Plant growth from each doses is proved to be varied. From germination viability on the third day, the highest percentage of seedling with leaves is on 100 Gy dose (73.75%), and 7, 14 and 21 day the lowest is on dose 400 Gy. (author)

Avoidance behaviour and anxiety in rats irradiated with a sublethal dose of gamma-rays.

Science.gov (United States)

Tomášová, Lenka; Smajda, B; Bona, M

2011-12-01

The aim of this study was to assess, whether a sublethal dose of gamma-rays will influence the avoidance behaviour and anxiety in rats and whether the response to radiation depends on time of day of its application. Adult male Wistar rats were tested in elevated plus-maze, in hot plate test and in the light/dark box in 4 regular intervals during a day. After two weeks the animals were irradiated with a whole-body dose 6 Gy of gamma-rays. One day after irradiation the animals were repeatedly tested in the same way, as before irradiation. In the plus-maze test an increased level of anxiety was established. The irradiation significantly decreased the locomotor activity of rats, but the extent of exploratory and comfortable behaviour were not altered. After irradiation, an elevated aversion to the thermal stimulus was observed in the hot plate test. The effects of radiation were more pronounced in the light period of the day, than in the dark one. No significant differences in aversion to light were detected after irradiation. The obtained results indicate, that sublethal doses of ionizing radiation can markedly influence the reactivity of animals to adverse stimuli, their motoric activity and emotional status, as well.

Gamma rays irradiation process on a restored painting from the XVII century

International Nuclear Information System (INIS)

Rizzo, Marcia M.; Machado, Luci D.B.; Rela, Paulo R.; Kodama, Yasko

2009-01-01

The aim of this work is to emphasize the importance of a previous study of the materials composition and behavior of any art work which will be treated by gamma radiation, as well as to use complementary procedures to prevent recontamination after the treatment, since this is a non residual method. As an example the object of study is a Peruvian painting from the 17th century, which has been restored, contaminated by mould, treated by gamma rays, put in a hermetic acrylic box and showed microorganisms growth after six years. A new treatment was performed using the same process and a complementary method using cloistering with anoxia atmosphere to prevent recontamination. Before the first irradiation the influence of irradiation process on the original painting and on the materials used in the restoration process were investigated. These data were extremely important in the decision of the use gamma irradiation again on the same art work. The results obtained allowed concluding that the irradiation with the recommended dose of 6.0 kGy (at the first time) was not sufficient to kill all the fungi specimens in the art work. On the other hand the irradiation with the dose of 6.0 kGy (at the first time) and 9.0 kGy (at the second time), according to the literature, would not damage the restored painting. (author)

Cellular response to low Gamma-ray doses

Energy Technology Data Exchange (ETDEWEB)

Manzanares A, E; Vega C, H R; Leon, L.C. de . [Unidades Academicas de Estudios Nucleares, Universidad Autonoma de Zacatecas, A.P. 336, 98000 Zacatecas (Mexico); Rebolledo D, O; Radillo J, F [Facultad de Ciencias Biologicas y Agropecuarias de la Universidad de Colima, Colima (Mexico)

2002-07-01

Lymphocytes, obtained from healthy donors, were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp70 and Hsc70.Hsp70 protein was detected after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 1.25 c Gy gamma-ray dose, lymphocytes expressed Hsp70 protein, indicating a threshold response to gamma rays. (Author)

Cellular response to low Gamma-ray doses

International Nuclear Information System (INIS)

Manzanares A, E.; Vega C, H.R.; Leon, L.C. de; Rebolledo D, O.; Radillo J, F.

2002-01-01

Lymphocytes, obtained from healthy donors, were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp70 and Hsc70.Hsp70 protein was detected after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 1.25 c Gy gamma-ray dose, lymphocytes expressed Hsp70 protein, indicating a threshold response to gamma rays. (Author)

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

International Nuclear Information System (INIS)

Park, Jae Nam; Han, In Jun; Kim, Wang Geun; Song, Beom Seok; Kim, Jae Hun; Choi, Jong Il; Yoon, Yo Han; Byun, Myung Woo; Hwang, Han Joon; Lee, Ju Woon; Park, Jin Gyu

2009-01-01

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

Effect of gamma rays on sex ratio, emergence and lifespan of cucurbits fruit fly dacus ciliatus (low) irradiated as pupae

International Nuclear Information System (INIS)

Al-Shmmary, A. J. M.; Al-Taweel, A. A.; Ahmed, R. F.

2012-12-01

The result showed the pupae at the age 1 or 2 days old was very sensitive to all doses of gamma rays, the percentage of adults emerged was zero at the dose of 45 gray and highest and the gigh percentage of adults emergence was recorded when the pupae irradiated at five days ald and the mean percentage of emerged adults was approximated with that of the control group. This study also showed that there was an effect of gamma radiation on the average percentage of deformed at adult stage and it was about 1:1 (male: female). On the other hand, the mean lifespan of females and mice s adult were decreased as the dose of gamma rays increases and the pupae irradiated at youngest ages. The longest life span of females was recorded when the pipa irradiated at five days old with any of the gamma rays dose. (Author)

Chemical and Biological Studies on Cumin Fruits Irradiated by GAMMA Rays for Conservation

International Nuclear Information System (INIS)

HASSANEIN, R.A.M.

2011-01-01

The aim of this study was to investigate the effect of different doses of gamma irradiation (0, 5, 10 and 15 KGy) and different storage periods (0, 3 and 6 months) in different package materials (cotton or polyethylene bags) on essential oil quality and chemical composition of cumin (Cuminum cyminum) fruits. On the other hand antimicrobial activity of treated cumin fruits essential oil and its extracts at 0, 5000, 10000, 20000 and 40000 ppm were investigated. Results showed that the highest essential oil % was obtained from fruits stored for 3 months in cotton bag without gamma irradiation. Concerning the effect of essential oil as antimicrobial agent, the highest antibacterial activity was obtained by essential oil isolated from irradiated polyethylene packed fruits at 5 KGy then stored for 3 months (Staphylococcus aureus) or irradiated polyethylene packed ones at 15 KGy without storage (Salmonella typhimurium). On the other hand, the highest antifungal activity against Aspergillus niger and Penicillium digitatum was obtained by essential oil isolated from unirradiated packed in polyethylene fruits then stored for 6 months. Non-stored packed in cotton bag fruits irradiated with gamma rays at 10 KGy produced essential oil with highest antiyeastal activity. Cumin fruits extract at 40000 ppm when combined with different treatments presented the highest antimicrobial activity (represents as inhibition zone) against all studied microbes except with P. digitatum. Cumin extract at 40000 ppm when extracted from irradiated packed fruits in polyethylene bags with gamma rays at 5 KGy without storage or with 6 months storage or irradiated at 15 KGy of packed fruits in cotton bag with storage for 3 months presented the highest significant inhibition zones against S. aureus. The same concentration of extracted cumin from uni radiated packed in cotton bag fruits and storage for 6 months presented the highest inhibition zone of S. typhimurium. Also, with the same concentration

Effect of Zi Gui decoction on immune function in {sup 60}Co {gamma}-ray irradiated mice

Energy Technology Data Exchange (ETDEWEB)

Qiujun, Lu; Shafei, Huang; Xipeng, Zhou; Jiayun, Song; Zhongxiong, Tang [Dept. of Pharmacology, Institute of Radiation Medicine, Beijing (China)

1995-02-01

Zi Gui decoction (ZG), a complex preparation of traditional Chinese herbal medicine, mainly consists of Radix Angelicae and Radix Astragali. The effects of ZG on mitogen induced proliferation IL-1 and -2 production, natural killer (NK) cell activity in {sup 60}Co {gamma}-ray irradiated mice is investigated. After 5 Gy whole body irradiation. mice were treated i.g. with ZG (1.2, 1.8 g/kg/day) for 20 days. An enhancement in Con A- and LPS-induced proliferations of splenocytes from the two dosage groups were observed. There were marked increases in IL-1 activity in peritoneal macrophage culturesa and IL-2 activity in splenocyte cultures from irradiated mice treated with ZG. The two dosage groups also showed significant potentiation of NK cell activity against YAC-1 target cells. The above results indicated that ZG could promote the recovery of immune functions in {gamma}-ray irradiated mice.

Neutron, gamma ray and post-irradiation thermal annealing effects on power semiconductor switches

Science.gov (United States)

Schwarze, G. E.; Frasca, A. J.

1991-01-01

The effects of neutron and gamma rays on the electrical and switching characteristics of power semiconductor switches must be known and understood by the designer of the power conditioning, control, and transmission subsystem of space nuclear power systems. The SP-100 radiation requirements at 25 m from the nuclear source are a neutron fluence of 10(exp 13) n/sq cm and a gamma dose of 0.5 Mrads. Experimental data showing the effects of neutrons and gamma rays on the performance characteristics of power-type NPN Bipolar Junction Transistors (BJTs), Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs), and Static Induction Transistors (SITs) are presented. These three types of devices were tested at radiation levels which met or exceeded the SP-100 requirements. For the SP-100 radiation requirements, the BJTs were found to be most sensitive to neutrons, the MOSFETs were most sensitive to gamma rays, and the SITs were only slightly sensitive to neutrons. Post-irradiation thermal anneals at 300 K and up to 425 K were done on these devices and the effectiveness of these anneals are also discussed.

Dose Distribution Calculation Using MCNPX Code in the Gamma-ray Irradiation Cell

International Nuclear Information System (INIS)

Kim, Yong Ho

1991-02-01

60 Co-gamma irradiators have long been used for foods sterilization, plant mutation and development of radio-protective agents, radio-sensitizers and other purposes. The Applied Radiological Science Research Institute of Cheju National University has a multipurpose gamma irradiation facility loaded with a MDS Nordin standard 60 Co source (C188), of which the initial activity was 400 TBq (10,800 Ci) on February 19, 2004. This panoramic gamma irradiator is designed to irradiate in all directions various samples such as plants, cultured cells and mice to administer given radiation doses. In order to give accurate doses to irradiation samples, appropriate methods of evaluating, both by calculation and measurement, the radiation doses delivered to the samples should be set up. Computational models have been developed to evaluate the radiation dose distributions inside the irradiation chamber and the radiation doses delivered to typical biolological samples which are frequently irradiated in the facility. The computational models are based on using the MCNPX code. The horizontal and vertical dose distributions has been calculated inside the irradiation chamber and compared the calculated results with measured data obtained with radiation dosimeters to verify the computational models. The radiation dosimeters employed are a Famer's type ion chamber and MOSFET dosimeters. Radiation doses were calculated by computational models, which were delivered to cultured cell samples contained in test tubes and to a mouse fixed in a irradiation cage, and compared the calculated results with the measured data. The computation models are also tested to see if they can accurately simulate the case where a thick lead shield is placed between the source and detector. Three tally options of the MCNPX code, F4, F5 and F6, are alternately used to see which option produces optimum results. The computation models are also used to calculate gamma ray energy spectra of a BGO scintillator at

Gamma-ray irradiation of a boreal forest ecosystem

International Nuclear Information System (INIS)

Guthrie, J.E.; Dugle, J.R.

1983-01-01

A long-term radiation ecology research project called Field Irradiator - Gamma (FIG) began at the Whiteshell Nuclear Research Establishment in 1968. The experimental area is in southeastern Manitoba and is located on the western edge of the Precambrian shield. The project studies the ecological effects continuous exposure to a gradient of gamma radiation has on a mixed boreal forest ecosystem. The gradient ranges from 1 to 460,000 times the natural background radiation level. This paper describes the forest, the gamma irradiator and its radiation field, and the research program

Relationship between free volume and mechanical properties of polyurethane irradiated by gamma rays

International Nuclear Information System (INIS)

Heliang Sui; Xin Ju; Xueyong Liu; Fachun Zhong; Xiaoyan Li; Baoyi Wang

2014-01-01

Polyurethane was irradiated at various gamma radiation doses up to 1,000 kGy at room temperature in nitrogen. Positron annihilation lifetime spectroscopy, tensile test and dynamic mechanical analysis were used to find the relationship between free volume and mechanical properties. An increase of the free volume fraction in soft segments (SS) and a decrease of the free volume fraction in hard segments (HS) during gamma radiation was observed and analyzed. The results showed that HS in polyurethane had the excellent resistance to gamma radiation, whereas SS had a tendency to degrade. The reason for the decrease of the strain at break and the ultimate tensile strength was analyzed, which showed the changes in the mechanical properties of polyurethane irradiated by gamma rays were mainly determined by the changes of free volume in SS. If the resistance properties of polyurethanes exposed to radiations need to be improved, SS should be paid more attention to. (author)

Behavioral changes in rats prenatally irradiated with low dose of gamma-rays

International Nuclear Information System (INIS)

Kiskova, J.; Smajda, B.; Capicikova, M.; Lievajova, K.

2006-01-01

In this work, the effects of prenatal gamma-irradiation on behavior in adult Sprague-Dawley rats were studied. Four months old female rats were irradiated with a dose of 1 Gy of gamma-rays on day 15 of gestation. The offspring of irradiated mothers (n=26) and that of control, non-irradiated mothers (n=36) of both sexes at the age of 3 month were tested in Morris's water maze and in open field test. All experimental groups showed a tendency to shortening the time needed to reach the platform in each trial in Morris water maze. Statistically significant difference between irradiated and control rats was detected only in males on 3 rd experimental day. The ability to remember the position of the platform was not altered in irradiated animals after a 4 day pause. In open field test, statistically significant differences in comparison with controls were detected in number of squares entered and in crossings of the central square (P ≤ 0.05) in males. These findings suggest, when comparing with results of other authors, that irradiation effects on postnatal behavior in rats are extremely dependent on the time point of irradiation and that a correlation exist between the developmental stage of the individual brain structures at time of irradiation and the late behavioral effects. (authors)

How gamma-rays and electron-beam irradiation would affect the antimicrobial activity of differently processed wild mushroom extracts?

Science.gov (United States)

Alves, M J; Fernandes, Â; Barreira, J C M; Lourenço, I; Fernandes, D; Moura, A; Ribeiro, A R; Salgado, J; Antonio, A; Ferreira, I C F R

2015-03-01

The effects of irradiation (gamma-rays and electron-beams), up to 10 kGy, in the antimicrobial activity of mushroom species (Boletus edulis, Hydnum repandum, Macrolepiota procera and Russula delica) differently processed (fresh, dried, freeze) were evaluated. Clinical isolates with different resistance profiles from hospitalized patients in Local Health Unit of Mirandela, Northeast of Portugal, were used as target micro-organisms. The mushrooms antimicrobial activity did not suffer significant changes that might compromise applying irradiation as a possible mushroom conservation technology. Two kGy dose (independently of using gamma-rays or electron-beams) seemed to be the most suitable choice to irradiate mushrooms. This study provides important results in antimicrobial activity of extracts prepared from irradiated mushroom species. © 2014 The Society for Applied Microbiology.

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

International Nuclear Information System (INIS)

2015-01-01

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

Behavior of the dynamic magnetic susceptibility in ybco bula ceramics irradiated with gamma rays

International Nuclear Information System (INIS)

Leyva Fabelo, A.; Bouza Dominguez, J.; Cruz Inclan, Carlos M.

2001-01-01

Using measurements of the ac susceptibility, the behavior with the irradiation dose of YBa2Cu3O7- bulk ceramics synthesized by the classic reaction method in solid state, was studied. A Co60 gamma chamber model MPX-G-25M and a Cs137 source were employed as gamma ray sources. The behavior of the beginning temperature of the normal - superconducting state transition with the exposition dose show, independently of the incident gamma energy, a monotonous growth until reaching a threshold dose, after which, observe a fall, more abrupt in the case of the Co60. This behavior can be explained using the model that postulates the ability of the gamma radiation, in certain dose intervals, to stimulate the structural reordering in the oxygen sublattice. When the irradiation process takes place in the Co60 gamma chamber, the behavior of the superconducting volume fraction of the sample characterizes by the initial sharp fall with the dose, followed with an attenuation of the decrement. In the case of Cs137 irradiation, the behavior of the superconducting volume fraction is similar to the behavior of the Ton with the dose

Studies on cannabis. III. Young plants from the seed irradiated with /sup 60/Co gamma rays for inhibiting their development after seeding

Energy Technology Data Exchange (ETDEWEB)

Shimomura, H; Kuriyama, E; Tomizawa, A [Tokyo Coll. of Pharmacy (Japan)

1976-01-01

The seedlings from Cannabis sativa L. seeds irradiated with different doses of ..gamma..-rays were examined, in order to determine the dose sufficient to kill the young plants naturally, before their hallucinnogenic component increases. The seeds of ''Minamioshihara No. 1'', which were harvested in 1972 in Tochigi Prefecture, were irradiated with eight different doses of /sup 60/Co ..gamma..-rays in January 17, 1973, and the seedlings were examined several times during the subsequent 9 months, from March to November 1973, and their morphological and histological effects were examined, and the results are summarized as follows: Samples irradiated with 1500 and 1000 krads developed radicles about 3 mm in length. Samples irradiated with 500, 200, and 50 krads grew into young plants with the first set of leaves, without lateral roots. Samples irradiated with 30 krads grew to about 10 cm high with a few lateral roots, and the epicotyls about 1 cm in length. These young plants from the irradiated seeds stayed in the same condition and then died. Samples irradiated with 15 and 5 krads grew in the same way as the controls until the stage of flowering. Samples irradiated with 500, 200, 50, and 30 krads showerd the cell membranes of endodermis and pericycle to be partially lignified and suberized. The degree of change was related to the dose of ..gamma..-rays. Samples irradiated with 30 krads showed withered cells near the end of the lateral nerves on the first and second set of leaves. The economical dose of /sup 60/Co ..gamma..-rays for inhibiting young plants from developing into adult ones was a minimum of 30 krads which made the young plants die. Irradiation with 50 krads of ..gamma..-rays will be required to kill the young plants completely before they develop the hallucinogenic component.

On-Line High Dose-Rate Gamma Ray Irradiation Test of the CCD/CMOS Cameras

Energy Technology Data Exchange (ETDEWEB)

Cho, Jai Wan; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-05-15

In this paper, test results of gamma ray irradiation to CCD/CMOS cameras are described. From the CAMS (containment atmospheric monitoring system) data of Fukushima Dai-ichi nuclear power plant station, we found out that the gamma ray dose-rate when the hydrogen explosion occurred in nuclear reactors 1{approx}3 is about 160 Gy/h. If assumed that the emergency response robot for the management of severe accident of the nuclear power plant has been sent into the reactor area to grasp the inside situation of reactor building and to take precautionary measures against releasing radioactive materials, the CCD/CMOS cameras, which are loaded with the robot, serve as eye of the emergency response robot. In the case of the Japanese Quince robot system, which was sent to carry out investigating the unit 2 reactor building refueling floor situation, 7 CCD/CMOS cameras are used. 2 CCD cameras of Quince robot are used for the forward and backward monitoring of the surroundings during navigation. And 2 CCD (or CMOS) cameras are used for monitoring the status of front-end and back-end motion mechanics such as flippers and crawlers. A CCD camera with wide field of view optics is used for monitoring the status of the communication (VDSL) cable reel. And another 2 CCD cameras are assigned for reading the indication value of the radiation dosimeter and the instrument. In the preceding assumptions, a major problem which arises when dealing with CCD/CMOS cameras in the severe accident situations of the nuclear power plant is the presence of high dose-rate gamma irradiation fields. In the case of the DBA (design basis accident) situations of the nuclear power plant, in order to use a CCD/CMOS camera as an ad-hoc monitoring unit in the vicinity of high radioactivity structures and components of the nuclear reactor area, a robust survivability of this camera in such intense gamma-radiation fields therefore should be verified. The CCD/CMOS cameras of various types were gamma irradiated at a

Comparison between poly(ethylene naphthalate) and poly(ethylene terephthalate) in terms of gamma-ray irradiation on their dielectric properties

Science.gov (United States)

Miyamoto, Maki; Ohki, Yoshimichi

2017-06-01

The effects of gamma-rays on the complex permittivity (\\varepsilon '\\text{r} and \\varepsilon ''\\text{r}) and electrical conductivity were compared between poly(ethylene naphthalate) (PEN) and poly(ethylene terephthalate) (PET). Although both \\varepsilon '\\text{r} and \\varepsilon ''\\text{r} increase in PET with an increase in the total dose of gamma irradiation, such increases are hardly observed in PEN. The conductivity is always smaller in PEN than in PET. Therefore, it has been confirmed that charge transport is less activated by gamma irradiation in PEN than in PET. Together with experimental results obtained by ultraviolet-visible absorption spectroscopy and thermogravimetric analysis, it can be concluded that PEN has a superior anti-gamma-ray dielectric property to PET.

The destructive degradation of some organic textile dye compounds using gamma ray irradiation

International Nuclear Information System (INIS)

Abdel-Gawad Emara, A.S.; Abdel-Fattah, A.A.; Ebraheem, S.E.; Ali, Z.I.; Gad, H.

2001-01-01

The destructive degradation of 8 coloured reactive and direct dye compounds currently used in the textile industry has been investigated. These dyes are: Levafix Blue ERA (LB), Levafix Brilliant Red E4BA (LBR), Levafix Brilliant Yellow EGA (LBY), Drimarene Scarlet F3G (DS), Drimarene Brilliant Green X3G (DBG), Fast Yellow RL (FY), Fast Violet 2RL (FV) and Fast Orange 3R (FO). The process of degradation of the respective dye has been followed spectrophotometrically at the characteristic lmax. The variation of the colour intensity of aerated aqueous solution of the investigated dyes has been measured as a function of gamma irradiation dose. In all cases, the amplitude of the absorption bands of the dye compound was found to decrease with the increase of the gamma dose. Irradiation was carried out for actual waste and distilled water. By comparing the heights of the absorption maxima in both the visible and ultraviolet ranges, it was found that complete decolouration is attained at lower doses than that needed for the process of degradation of the dye. The kinetics of the degradation process has been traced and the kinetic constant, k 1 , was calculated and found to be concentration dependent indicating a first order reaction in all cases. The radiation-chemical yield (G-value) as a measure of the efficiency of gamma ray to degrade the respective dye was calculated for all dye compounds and it was found that the G-value in all cases increases exponentially for low radiation doses and changes linearly for high radiation doses. Also the K* value (the efficiency coefficient of dye radiolysis) was calculated and compared for the different dye compounds e.g. for FO, FY and FV dyes, the K* values were found to range from 5.5x10 9 to 1.92x10 -7 mol·L -1 '·cm -1 . In addition to the study of a single dye compound in solution, mixtures of different dyes (3 dyes) were also subjected to g-ray irradiation simulating more closely actual waste effluents. Also the effect of some

Genetic studies on two soybean cultivars irradiated with gamma rays

International Nuclear Information System (INIS)

El-Demerdash, H.M.

2007-01-01

In the present study, the effect of gamma irradiation was used in two Egyptian soybean cultivars; Giza-22 and Giza-82, to induce genetic variability with doses of 100, 150 and 200 Gy. Some agronomic characters were tested in M1 and M2 generations single plants. Oil and protein contents were measured from the resulted mutants of the two soybean cultivars at M2 generation. Some genetic parameters were estimated on the mean values of M2 generation. The results showed significant differences induced by gamma ray doses in all studied characters, particularly for 200 Gy in M1 generation. Gamma irradiation increased the genetic variability in M2 generation, which helped in selecting some high yielding mutants and some mutants with high oil and protein contents from the two cultivars. The estimated coefficients of phenotypic variance as well as coefficient of genotypic variance were high for seeds weight/plant, pod weight/plant, number of seeds/plant, number of pods/plant and number of nods/plant which showed better scope in genetic improvement. Heritability in the broad sense was high in most of the studied characters. The expected genetic advance (G.A) from selection was high for number of seeds, for number of pods, for pods weight and for mature plant height

Fluorescence of irradiated hydrocarbons. [. gamma. rays

Energy Technology Data Exchange (ETDEWEB)

Gulis, I G; Evdokimenko, V M; Lapkovskii, M P; Petrov, P T; Gulis, I M; Markevich, S V [AN Belorusskoj SSR, Minsk. Inst. Fiziko-Organicheskoj Khimii

1977-01-01

A visible fluorescence has been found out in ..gamma..-irradiated aqueous solutions of carbohydrates. Two bands have been distinguished in fluorescence spectra of the irradiated solution of dextran: a short-wave band lambdasub(max)=140 nm (where lambda is a wave length) at lambdasub(..beta..)=380 nm and a long-wave band with lambdasub(max)=540 nm at lambdasub(..beta..)=430 nm. A similar form of the spectrum has been obtained for irradiated solutions of starch, amylopectin, low molecular glucose. It has been concluded that a macromolecule of polysaccharides includes fluorescent centers. A relation between fluorescence and ..cap alpha..-oxiketon groups formed under irradiation has been pointed out.

Induced parthenocarpy with pollen irradiated with gamma rays

International Nuclear Information System (INIS)

Dryanovska, O.

1975-01-01

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

Comparative experiments for tube agglutination test of pullorum antiserum with gamma ray Co/sup 60/ irradiated salmonella pullorum

Energy Technology Data Exchange (ETDEWEB)

Seo, B K [City Univ. of Seoul, Seoul (Republic of Korea)

1976-01-01

An agglutinability between naturally infected positive chicken serum of pullorum disease and hyperimmunized rabbit antiserum was compared. And the following results were obtained and summarized. On the agglutinability, Salmonella pullorum antigen which irradiated gamma-ray was better than another both formalized and heated antigen. Time of judgemented as positive titer in the tube agglutination test to the naturally infected positive chicken serum was it most suitable for 12 hours at 37/sup 0/C. Agglutination titer of positive immune chicken serum against gamma-ray irradiate Salmonella pullorum were as 320 approximately 640x.

Selection of variants with high levels of biotin from cultured green Lavandula vera cells irradiated with gamma rays

International Nuclear Information System (INIS)

Watanabe, K.; Yamada, Y.

1982-01-01

Cultured green Lavandula vera cells were irradiated with various dosages of gamma rays which increased the variation in the amount of free biotin produced by the cell clones. Variant sublines containing much more free biotin than the original line were obtained by repeated selection. The effectiveness of gamma rays for the induction of the variant sublines is described

Modifications in the Morphology of Poly(styrene-co-divinylbenzenes) Induced by Gamma-ray Irradiation

Czech Academy of Sciences Publication Activity Database

Aleksieva, Krasimira; Sassi, A.; Jeřábek, Karel

2010-01-01

Roč. 70, č. 6 (2010), s. 361-365 ISSN 1381-5148 Institutional research plan: CEZ:AV0Z40720504 Keywords : gamma -ray irradiation * specific surface area * polymer morphology Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.546, year: 2010

Neutron, gamma ray and post-irradiation thermal annealing effects on power semiconductor switches

International Nuclear Information System (INIS)

Schwarze, G.E.; Frasca, A.J.

1994-01-01

The effects of neutrons and gamma rays on the electrical and switching characteristics of power semiconductor switches must be known and understood by the designer of the power conditioning, control, and transmission subsystem of space nuclear power systems. The SP-100 radiation requirements at 25 m from the nuclear source are a neutron fluence of 10 13 n/cm 2 and a gamma dose of 0.5 Mrads. Experimental data showing the effects of neutrons and gamma rays on the performance characteristics of power-type NPN Bipolar Junction Transistors (BJTs), Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs), and Static Induction Transistors (SITs) are given in this paper. These three types of devices were tested at radiation levels which met or exceeded the SP-100 requirements. For the SP-100 radiation requirements, the BJTs were found to be most sensitive to neutrons, the MOSFETs were most sensitive to gamma rays, and the SITs were only slightly sensitive to neutrons. Post-irradiation thermal anneals at 300 K and up to 425 K were done on these devices and the effectiveness of these anneals are also discussed

Induced mitotic gynogenesis in common carp (Cyprinus carpio L.), optimizing irradiation dose of X- and gamma-ray

International Nuclear Information System (INIS)

Yousefian, M.; Amirinia, C.; Bercsenyi, M.; Horvath, L.

1997-01-01

Mitotic gynogenesis was induced in common carp, Cyprinus carpio L., in hatchery and laboratory conditions, using 60Co gamma-ray and X-ray for inactivation of sperm DNA and a subsequent heat shock for inducing endomitosis. The parameter examined was the dose of irradiation in the range of 70-140 Krad. Carp spermatozoa irradiated by 70-100 Krad doses showed higher motility and fertilization ability than the ones irradiated by 110-140 Krad. Sperm treated with doses of 70-90 Krad showed the same fertility rate, but lower survival rate at embryo stage compared with 100 Krad. The shock temperature and duration applied in these experiments for restoration of diploidy level were 40 degrees C plus/minus 0.1 and 2 min., respectively. The highest frequency of mitotic gynogenetic larvae was achieved by 100 Krad 60Co gamma ray at 34 min. after fertilization, - up to 12.2 percent (at 23 degrees C incubating temperature)

Molecular characteristics of fungus trichoderma viride irradiated gamma rays

International Nuclear Information System (INIS)

Dadang Sudrajat; Nana Mulyana; Tri Retno DL; Rika Heriyani; Almaida

2016-01-01

Information about the genetic changes due to irradiation on the fungus Trichoderma viride is indispensable in order to improve the ability of these isolates for the delignification of lignocellulose. This study aims to determine the molecular characteristics of isolates fungus Trichoderma viride after irradiation with gamma rays through an approach expression of protein profiles and molecular markers random amplified polymorphic DNA (RAPD). Irradiation doses used in this study are 6 levels i.e 0; 75; 125; 250; 375; 500 and 750 Gy with a dose rate of 0.21 kGy / hour. Protein and DNA extraction isolate is done using the method of extracting phosphate buffer pH 7 and CTAB- phenol-chloroform extraction. Protein in the supernatant was analyzed by electrophoresis (SDS-gel polyacrylamide) to produce a protein fingerprint profile. Randomly amplified polymorphic DNA (RAPD) markers were used to estimate the genetic variations between 7 isolates of irradiated Trichoderma viride which were RAPD reactions using 3 random primers. The results showed that protein profiles generated by irradiation isolates and the control (no irradiation) gave a different pattern, especially at doses of irradiation 250-750 Gy based dendrogram analysis. DNA-RAPD profile showed a high genetic variation between the isolates were irradiated at a dose of 250; 375; 500 and 750 Gy and isolates the control (0 Gy); 75; 125 Gy with 5 cluster formation. Dendrogram analysis showed the coefficient of similarity between 0.62 to 0.68. (author)

Studies on the effect of gamma-rays irradiation on the virulence and immunogenicity of Eimeria tenella oocysts

International Nuclear Information System (INIS)

Hayat, Birjees

1976-01-01

Complete attenuation of the infective oocysts of Eimeria tanella was obtained with a gamma ray dose of 15000r. Above this dose, pathogenicity and the sensitivity of the disease decreased. There was no difference in the level of immunity induced with irradiated and non-irradiated oocysts, but the mortality with the irradiated oocysts was much lower. (ARA)

Conductivity enhancement in SiO2 doped PVA:PVDF nanocomposite polymer electrolyte by gamma ray irradiation

Science.gov (United States)

Hema, M.; Tamilselvi, P.; Pandaram, P.

2017-07-01

Nanocomposite polymer electrolyte has been irradiated with 15 Gy Gamma rays. Exposure of gamma radiation caused scissoring and crosslinking of polymer chains thereby increasing amorphous phase of the polymer matrix because of which the ionic conductivity has been enhanced. Ionic conductivity of irradiated nanocomposite polymer electrolyte is enhanced to 9.4 × 10-4 Scm-1 at 303 K compared to un-irradiated system (σ ∼ 1.7 × 10-4 Scm-1). Temperature dependence of ionic conductivity of both un-irradiated and irradiated systems obeys VTF relation. Frequency and temperature dependence of dielectric and modulus of both systems have been analyzed. The ionic transference number of polymer electrolyte has been calculated by Wagner's polarization technique and it confirms that conducting species are predominantly due to ions in both systems.

Responses of commercial broiler chicks to 60Co gamma-rays

International Nuclear Information System (INIS)

Shebaita, M.K.; Kamar, G.A.R.; El-Barkouky, E.E.M.

1981-01-01

A total of 360 chicks of Nichols line at one-day old were used in this study. Within each sex, the chicks were divided into three exposure treatments (non-irradiated, 400 rads and 800 rads). The source of irradiation was 60 Co gamma-rays. The results can be summarized as follows: Of the 360 chicks used in this study, only 10 chicks died during the experimental period. Radiation induced a reduction in body weight in both sexes during the growth period. Gamma-rays reduce the feed intake in both sexes. Moreover, the feed conversion ratio for the irradiated chicks was higher than that the non-irradiated birds. While red blood cells and hemoglobin content were higher in the irradiated chicks, white blood cells count and especially lymphocytes did not affect by 60 Co gamma-rays. Gamma-rays had no effect on carcass, bone, meat and giblets as fractions of body weight in both sexes. Moreover, meat water content decreased and meat fat content increased in irradiated chicks. The total length and the total weight of the GI tract decreased due to 60 Co gamma-rays. The response of the different regions of the GI tract to this rays is different. Moreover, the effect of this radiation on the GI tract is dependent upon the body weight irrespective of the sex. (orig./MG) [de

Utilization of freshly induced high-energy gamma-ray activity as a measure of fission rates in re-irradiated burnt UO{sub 2} fuel

Energy Technology Data Exchange (ETDEWEB)

Murphy, M. F.; Perret, G. [Paul Scherrer Institut (PSI), CH-5232 Villigen (Switzerland); Krohnert, H.; Chawla, R. [Paul Scherrer Institut (PSI), CH-5232 Villigen (Switzerland); Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

2009-07-01

In the frame of the LIFE-PROTEUS (Large-scale Irradiation Fuel Experiments at PROTEUS) program, a measurement technique is being developed to measure fission rates in burnt fuel, following re-irradiation in a zero-power research reactor. In the presented approach, the fission rates are estimated by measuring high energy gamma-rays (above 2000 keV) emitted by short-lived fission products freshly produced in the fuel. Due to their high energies, these gamma-rays can be discriminated against the high intrinsic gamma-ray activity of the burnt fuel, which reaches energies up to 2000 keV. To demonstrate the feasibility of this approach, fresh and burnt fuel samples (with burn-ups varying from 36 to 64 MWd/kg) were irradiated in the PROTEUS reactor at the Paul Scherrer Institut, and their emitted gamma-ray spectra were recorded shortly after irradiation. It was possible, for the first time, to detect the short-lived gamma-ray activity in the high-energy region, even in the presence of the intrinsic gamma-ray background of the burnt fuel samples. Using the short-lived gamma-ray lines {sup 142}La (2542 keV), {sup 89}Rb (2570 keV), 95Y (2632 keV), {sup 138}Cs (2640 keV) and {sup 95}Y (3576 keV), relative fission rates between different core positions were derived for a fresh sample as well as for a burnt sample with a burn-up of 36 MWd/kg. It was shown that, for both the fresh and burnt fuel samples, the measured fission rate ratios agreed well, i.e. within the statistical uncertainties, with calculation results obtained by Monte Carlo simulations. (authors)

Gamma scanning of the irradiated HANARO fuels

International Nuclear Information System (INIS)

Hong, Kwon Pyo; Lee, K. S.; Park, D. G.; Baik, S. Y.; Song, W. S.; Kim, T. Y.; Seo, C. K.

1997-02-01

To conform the burnup state of the fuels, we have transported the irradiated HANARO fuels from the reactor to IMEF (Irradiated Material Examination Facility), and executed gamma scanning for the fuels. By measuring the gamma-rays from the irradiated fuels we could see the features of the relative burnup distributions in the fuel bundles. All of 17 fuel bundles were taken in and out between HANARO and IMEF from March till August in 1996, and we carried out the related regulations. Longitudinal gamma scanning and angular gamma scanning are done for each fuel bundle without dismantlement of the bundles. (author). 5 tabs., 25 figs

Biochemical and pharmacological characterization of irradiated crotamine by gamma rays of 60Co

International Nuclear Information System (INIS)

Oliveira, Karina Corleto

2014-01-01

The serum production in Brazil, the only effective treatment in cases of snakebites, uses horses that although large size, have reduced l lifespan compared with horses not immunized. Ionizing radiation has been shown as an excellent tool in reducing the toxicity of venoms and toxins isolated, and promote the achievement of better immunogens for serum production, and contributing to the welfare of serum-producing animals. It is known, however, that the effects of ionizing radiation on protein are characterized by various chemical modifications, such as fragmentation, cross-linking due to aggregation and oxidation products generated by water radiolysis. However, the action of gamma radiation on toxins is not yet fully understood structurally and pharmacologically, a fact that prevents the application of this methodology in the serum production process. So we proposed in this paper the characterization of crotamine, an important protein from the venom of Crotalus durissus terrificus species, irradiated with 60 Co gamma rays. After isolating the toxin by chromatographic techniques and testing to prove the obtaining of pure crotamine, it was irradiated with gamma rays and subjected to structural analysis, Fluorescence and Circular Dichroism. Using high hydrostatic pressure tests were also conducted in order to verify that the conformational changes caused by radiation suffer modifications under high pressures. From the pharmacological point of view, muscle contraction tests were conducted with the objective of limiting the action of crotamine in smooth muscle as well as the change in the action of toxin caused structural changes to the front. Analysis of Circular Dichroism and Fluorescence showed changes in structural conformation of crotamine when subjected to gamma radiation and that such changes possibly occurring in the secondary and tertiary structure of the protein. The observed in pharmacological tests showed that the irradiated crotamine was less effective in

Curcuma sparganifolia Improvement Through Gamma Irradiation

International Nuclear Information System (INIS)

Krasaechai, A.

1990-01-01

The studies of Curcuma sparganifolia improvement through irradiation using gamma rays from 40 Gy to inhibit sprouting of the rhizomes were conducted. Various effects of gamma rays on growth and development were observed in 11 parameters. Colour mutation of flowers and braces were not found except in 1 plant which showed deeper brats colour. Leaf chimera was observed but the characters for commercialization were not achieved

Influence of gamma-ray irradiation on 6H-SiC MOSFETs

International Nuclear Information System (INIS)

Ohshima, Takeshi; Yoshikawa, Masahito; Itoh, Hisayoshi; Nashiyama, Isamu; Okada, Sohei

1998-01-01

Enhancement-type n-channel MOSFETs were fabricated on 6H-SiC epitaxial films using pyrogenic or dry oxidation process. Oxide-trapped charges and interface traps produced in 6H-Sic MOSFETs by gamma-ray irradiation are evaluated from changes in the subthreshold-current curve. The net numbers of radiation-induced-oxide-trapped charges and interface traps depend on the oxidation process. The 6H-SiC MOSFETs exhibit higher radiation resistance than Si MOSFETs. (author)

Influence of gamma rays irradiation to chlorphyriphos insecticides residues in grapes (vitis vinifera L.)

International Nuclear Information System (INIS)

Chairul, S.M.

2012-01-01

Simulation methods to determination of chlorphyriphos insecticides residue in grapes cause effect gamma rays, was done. Fruits of grapes soaked with chlorpyriphos insecticide solution high level concentrated (100 ppm; 200 ppm; and 300 ppm) for 3 (three minutes). The treatment of the sample was direct of extraction after soaks; extract after storage for one week after soak, and extract after soak after storage for one week after irradiation at 0.5 kGy; 1.0 kGy; and 1.5 kGy dose. Extraction methods using ethyl acetate solvent, and using sodium sulphate as to dryed water level in grapes, and then extractan was injected to chromatography gas use electron capture detector. The result indicated that occur of descent of chlorpyrifos residues from eachs soaked consequence at storage for one week was amount 7,55; 8,42; and 18,88% respectively, while of consequence irradiation of gamma ray at 0,5 kGy doses, will be descent of chlorpyrifos residues in amount 13,90; 19,16; and 52,79% respectively, and at 1,0 kGy doses irradiation will be descent in amount 34,45; 36,15 and 49,79%, respectively. (author)

Effects of gamma Rays Irradiation on resistance of Pseudomonas aeruginosa in various condition

International Nuclear Information System (INIS)

Nikham

2002-01-01

The investigation of gamma tays 60Co irradiation effect on resistance of bacteri P.aeruginosa has been done.The objective of the research was to know the D10 value of bacteria P.aeruginosa. By using of distilled water,talc and peanut powder as carrier in dry,wet,O 2 and N 2 condition the bacteria of P.aeruginosa were irradiated on gamma rays of 6 0Co with dose of O to 2.5 kGy,and with dose rate of 5 and 10 kGy/h.After irradiation the bacteria of P. aeruginosa were cultured in media of the Tryptone Soya Agar and incubatedat temperature of 32±2 o C for 3 days. The survival colonies were calculated,and the data were used to make the curve and to determine the D10 value. The results of the experiments showed that D10 value of irradiated bacteria of P.aeruginosain the disitilled water,talc and peanut powder as carrier were not high significant.Nevertheless the D10 value of the irradiated at dose rate 10kGy/h show more higher tendency than at dose rate 5kGy/h. The D10 value of irradiated bacteria in the N2 condition was higher,if compared with in the O2 condition

Method and apparatus for neutron induced gamma ray logging for lithology identification

International Nuclear Information System (INIS)

Oliver, D.W.; Culver, R.B.

1981-01-01

The patent describes a neutron-gamma well logging technique which can distinguish between sandstone and limestone formations irrespective of water salinity in the formation. The formation surrounding a borehole is irradiated by fast neutrons and the resulting gamma rays are counted. The gamma rays are converted to electrical signals in three distinct steps; the first two signals result from gamma rays associated with calcium content of the formation and the third signal from gamma rays associated with silicon content. Gamma rays resulting from irradiation of calcium are counted at two non-contiguous energy bands. (O.T.)

Teratogenic effects of 60Co gamma rays irradiation on rat embryos

International Nuclear Information System (INIS)

Lee, Juing-Yi; Okuda, Hiroe; Tutimoto, Sigeo; Satow, Yukio

1987-01-01

The teratogenicity of 60 Co gamma rays was evaluated in Donryu rats. The results were compared with those of triterated water (HTO) for determining relative biological effectiveness (RBE) for incidence of malformations and LD 50 in rats. Pregnant rats were irradiated with a 60 Co source at a dose-rate of 0.5 Gy/min or 0.01 Gy/min on day 7, 8, 9, 10 or 11 of gestation with 0.8, 1.0, 1.2, 1.5, 2.0, 2.3, 2.5, 2.8 or 3.0 Gy. HTO was administered intraperitoneal injection to pregnant rats at various doses on day 7, 8, 9, 10 and 11 of gestation. The rats were sacrificed on day 18 and the offspring were examined for external and visceral malformations. Mortality, teratogenicity and effects on fetal growth were day-and dosage-dependent in both radiation groups. Congenital malformations were found most frequently in the 9-day irradiated group and followed by the 8, 11, 10 and 7-day irradiated groups. The incidence of cardiovascular anomalies was highest, especially in the day 9 of gestation group, followed by malformations in the central nervous system, craniofacial system, respiratory system, hind limbs and tail. Beta rays from HTO were found to be more effective than γ rays in inducing congenital malformations. The RBE for incidence of malformations and LD 50 was between 1.3 and 1.5. These studies suggest that simulator of tritium irradiation is urgently needed to investigate the biological effects on rats to estimate the human risks, with respect to RBE of tritium beta rays. (author)

Thermal, tensile and rheological properties of high density polyethylene (HDPE) processed and irradiated by gamma-ray in different atmospheres

Energy Technology Data Exchange (ETDEWEB)

Ferreto, H. F. R., E-mail: hferreto@ipen.br, E-mail: ana-feitoza@yahoo.com.br; Oliveira, A. C. F., E-mail: hferreto@ipen.br, E-mail: ana-feitoza@yahoo.com.br; Parra, D. F., E-mail: dfparra@ipen.br, E-mail: ablugao@ipen.br; Lugão, A. B., E-mail: dfparra@ipen.br, E-mail: ablugao@ipen.br [Center of Chemistry and Environment, Institute of Energy and Nuclear Research - IPEN (Brazil); Gaia, R., E-mail: renan-gaia7@hotmail.com [Faculdades Oswaldo Cruz (Brazil)

2014-05-15

The aim of this paper is to investigate structural changes of high density polyethylene (HDPE) modified by ionizing radiation (gamma rays) in different atmospheres. The gamma radiation process for modification of commercial polymers is a widely applied technique to promote new physical-chemical and mechanical properties. Gamma irradiation originates free radicals which can induce chain scission or recombination, providing its annihilation, branching or crosslinking. This polymer was irradiated with gamma source of {sup 60}Co at doses of 5, 10, 20, 50 or 100 kGy at a dose rate of 5 kGy/h. The changes in molecular structure of HDPE, after gamma irradiations were evaluated using thermogravimetric analysis (TGA) and tensile machine and oscillatory rheology. The results showed the variations of the properties depending on the dose at each atmosphere.

Apparatus for gamma ray radiography

International Nuclear Information System (INIS)

Kobayashi, Masatoshi; Enomoto, Shigemasa; Oga, Hiroshi

1979-01-01

This is the standard of Japan Non-Destructive Inspection Society, NDIS 1101-79, which stipulates on the design, construction and testing method of the apparatuses for gamma ray radiography used for taking industrial radiograms. The gamma ray apparatuses stipulated in this standard are those containing sealed radioactive isotopes exceeding 100 μCi, which emit gamma ray. The gamma ray apparatuses are classified into three groups according to their movability. The general design conditions, the irradiation dose rate and the sealed radiation sources for the gamma ray apparatuses are stipulated. The construction of the gamma ray apparatuses must be in accordance with the notification No. 52 of the Ministry of Labor, and safety devices and collimators must be equipped. The main bodies of the gamma ray apparatuses must pass the vibration test, penetration test, impact test and shielding efficiency test. The method of each test is described. The attached equipments must be also tested. The tests according to this standard are carried out by the makers of the apparatuses. The test records must be made when the apparatuses have passed the tests, and the test certificates are attached. The limit of guarantee by the endurance test must be clearly shown. The items to be shown on the apparatuses are stipulated. (Kako, I.)

Effect of Gamma irradiation on the Production of Four Species of Some Labiateae Family

International Nuclear Information System (INIS)

El-Sharnouby, M.E.

2013-01-01

This investigation was carried out on four species of Labiateae family (Sweet basil, Marjoram, Rosemary and Thyme), plants cultured on Taif region in KSA and seeds were exposed to gamma rays treatments at 20, 40, 60 and 80 Gy. The results indicated increase the number of shoots of all labiateae species with control plants after 2 and 4 months (except Rosmary seeds irradiated with 20 Gy of gamma irradiation which produced maximum number of shoots (3.1) after four months from seeds culturing). The highest dose of gamma rays (80 Gy), significantly decreased the average shoot number on Marjoram plants. Exposing to gamma irradiation, the irradiated sweet basil plants with gamma rays at 40 and 60 Gy formed significantly longer shoots after 4 months from culturing compared with the control plants. The high dose of gamma rays (80 Gy), significantly decreased the average of Marjoram shoot length. The Rosmary plants, showed a significant increase in the shoot length with gamma irradiation at 20 Gy which produced (4.0 cm) than other gamma irradiation treatments. Stem diameter and plant dry weight of the Rosmary, Marjoram and Thyme plants were the best on control than other gamma rays treatments after 2 and 4 months respectively. The highest number of leaves percentage (12.2) was recorded with the control of marjoram plants. Most of the irradiation treatments decreased the number of leaves of all labiateae plants except sweet basil plants specially gamma ray at 60 Gy which reached more number of leaves than sweet basil control plants after 4 months from seeds culturing.

Perna perna (LINNAEUS, 1758) mussels irradiated by 60CO gamma rays cytotoxicity evaluation

International Nuclear Information System (INIS)

Martini, Gisela A.; Pusceddu, Fabio H.; Rogero, Sizue O.; Rogero, Jose Roberto

2013-01-01

The aim of the present work was the study of ionizing radiation effects on aquatic biota regarding the location of nuclear facilities nearby coastal areas assuming the risk of leaks and nuclear accidents. Bivalve mollusks have been widely used in the monitoring of aquatic environment studies mainly for their sessile habit and pollutants bioconcentration ability. So marine mussel Perna perna (Bivalvia: Mytilidae) was used as organism test in this study. The study of radioactive toxicity was performed by cytotoxicity test exposing the organisms to 11Gy gamma radiation dose. After radiation the neutral red retention assay evaluated the lysosomal membrane integrity in the mussel hemocytes. 50% lethal dose assay (LD50) of gamma radiation on Perna perna mussels was carried out by exposure the organisms to 60 Co gamma rays at doses ranging from 0 to 3000 Gy. The result of gamma radiation LD50 for these mussels was 1068 Gy and the neutral red retention time of irradiated organisms was about 47% lower than the control, non irradiated organisms. With the obtained results is expected to contribute in the study to identify the range of ionizing radiation doses which can cause toxic effects in marine invertebrates. (author)

Physicochemical Properties of Gamma-Irradiated Corn Starch

International Nuclear Information System (INIS)

Lee, Y.J.; Lim, S.T.; Kim, S.Y.; Han, S.M.; Kim, H.M.; Kang, I.J.

2006-01-01

Structural modification of corn starch by gamma irradiation was evaluated for under dry conditions at varied intensities from 0 to 40 kGy. Under scanning electron microscopy, the granule shape of corn starch was not significantly affected by the irradiation up to 40 kGy. In addition, X-ray diffraction and melting patterns of the irradiated starches were similar to those of the native starch, indicating that crystalline regions in the starch granules were not changed by irradiation. However, the pattern of gel permeation column chromatography showed a significant increase in partial hydrolysis of gamma irradiated starch samples

Broccoli yield and yield quality as affected by gamma rays seeds irradiation and foliar application of some nutrients

Energy Technology Data Exchange (ETDEWEB)

Gabal, M R [Botany Department, Faculty of Agriculture, Moshtohor, Zagazig University (Egypt); Abdallah, A A.G.; Awad, S M; Aboel-Kheir, O H [Plant Research Department, Nuclear Research Centre, Cairo (Egypt)

2005-07-01

Two field experiments were carried out during 1999/2000 and 2000/2001 winter growing seasons at the Atomic Energy Authority (AEA) in Inshas, Egypt. The experiment was conducted to study the effect of pre-sowing seeds irradiation with different doses of gamma rays (0, 2, 3 and 4 Gy) and foliar application of different nutrients (Zn, B, S and S+K) on spear diameter, main spear fresh and dry weight per plant, total spear fresh weight per plant, total spear yield besides NPK in leaves at 90 days after transplanting and NPK and total protein content in spears at maturity. In general, exposing broccoli seeds to different gamma ray doses up to 4 Gy prior to sowing increased the above mentioned parameters with different magnitudes comparing with the non-irradiated control plants. There were no significant differences between 3 Gy and 4 Gy treatments during the two growing seasons. With respect to the effect of nutrient application on the studied parameters, all nutrients application significantly increased all the above mentioned parameters. The highest result was detected with B application. Regarding to the interaction of gamma ray with nutrients application, the highest value of all above mentioned parameters was detected with B application and 3 Gy of gamma ray.

Broccoli yield and yield quality as affected by gamma rays seeds irradiation and foliar application of some nutrients

International Nuclear Information System (INIS)

Gabal, M.R.; Abdallah, A.A.G.; Awad, S.M.; Aboel-Kheir, O.H.

2005-01-01

Two field experiments were carried out during 1999/2000 and 2000/2001 winter growing seasons at the Atomic Energy Authority (AEA) in Inshas, Egypt. The experiment was conducted to study the effect of pre-sowing seeds irradiation with different doses of gamma rays (0, 2, 3 and 4 Gy) and foliar application of different nutrients (Zn, B, S and S+K) on spear diameter, main spear fresh and dry weight per plant, total spear fresh weight per plant, total spear yield besides NPK in leaves at 90 days after transplanting and NPK and total protein content in spears at maturity. In general, exposing broccoli seeds to different gamma ray doses up to 4 Gy prior to sowing increased the above mentioned parameters with different magnitudes comparing with the non-irradiated control plants. There were no significant differences between 3 Gy and 4 Gy treatments during the two growing seasons. With respect to the effect of nutrient application on the studied parameters, all nutrients application significantly increased all the above mentioned parameters. The highest result was detected with B application. Regarding to the interaction of gamma ray with nutrients application, the highest value of all above mentioned parameters was detected with B application and 3 Gy of gamma ray

Responses of commercial broiler chicks to /sup 60/Co gamma-rays

Energy Technology Data Exchange (ETDEWEB)

Shebaita, M.K.; Kamar, G.A.R.; El-Barkouky, E.E.M.

1981-12-01

A total of 360 chicks of Nichols line at one-day old were used in this study. Within each sex, the chicks were divided into three exposure treatments (non-irradiated, 400 rads and 800 rads). The source of irradiation was /sup 60/Co gamma rays. The results can be summarized as follows: Of the 360 chicks used in this study, only 10 chicks died during the experimental period. Radiation induced a reduction in body weight in both sexes during the growth period. Gamma rays reduce the feed intake in both sexes. Moreover, the feed conversion ratio for the irradiated chicks was higher than that the non-irradiated birds. While red blood cells and hemoglobin content were higher in the irradiated chicks, white blood cells count and especially lymphocytes were not affected by /sup 60/Co gamma rays. Gamma rays had no effect on carcass, bone, meat and giblets as fractions of body weight in both sexes. Moreover, meat water content decreased and meat fat content increased in irradiated chicks. The total length and the total weight of the GI tract decreased due to /sup 60/Co gamma rays. The response of the different regions of the GI tract to these rays is different. Moreover, the effect of this radiation on the GI tract is dependent upon the body weight irrespective of the sex.

Pollen-gamma irradiation on pineapple and pollination using irradiated pollen

International Nuclear Information System (INIS)

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

1997-01-01

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

Inactive Doses and Protein Concentration of Gamma Irradiated Yersinia Enterocolitica

International Nuclear Information System (INIS)

Irawan Sugoro; Sandra Hermanto

2009-01-01

Yersinia enterocolitica is one of bacteria which cause coliform mastitis in dairy cows. The bacteria could be inactivated by gamma irradiation as inactivated vaccine candidate. The experiment has been conducted to determine the inactive doses and the protein concentration of Yersinia enterocolitica Y3 which has been irradiated by gamma rays. The cells cultures were irradiated by gamma rays with doses of 0, 100, 200, 400, 600, 800, 1.000 and 1.500 Gy (doses rate was 1089,59 Gy/hours). The inactive dose was determined by the drop test method and the protein concentration of cells were determined by Lowry method. The results showed that the inactive doses occurred on 800 – 1500 Gy. The different irradiation doses of cell cultures showed the effect of gamma irradiation on the protein concentration that was random and has a significant effect on the protein concentration. (author)

Determination quercetin content, antioxidant and antimicrobial activity of genotype mutant Samosir shallots irradiated by gamma rays

Science.gov (United States)

Sinuraya, M.; Hanafiah, D. S.; Romulo, A.; Barus, A.

2018-02-01

The aim of the research was to study the variation in antioxidant and antimicrobial activity as well as the total quercetin content of the fifth generation genotypes mutant Samosir shallot irradiated by gamma rays. The studies conducted included the assessment of quercetin content, antioxidant and antimicrobial activity in shallot bulbs after long-term storage (6 months in the room temperature). Quercetin content of 20 selected genotype mutants of irradiated shallot bulbs along with untreated populations were calculated using quercetin (QU) as a standard. Antioxidant activities of 8 genotype mutant were determined using DPPH. Antimicrobial activity of bulb extracts were tested against six bacteria including Staphylococcus aurous, Enterococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae and oneyeastCandida albicans. The results showed that population of genotype mutants irradiated with dosage 2Gy, 4 Gy, 5 Gy and 6 Gy have higher quercetin content than control samples. None of the genotype mutants exhibited antibacterial inhibitory against all microorganism tested except for the sample number 2 and 6 (bulbs generated from the plants irradiated by gamma rays with dosage at 2 Gy and 6 Gy). There was also none of the genotypes observed exhibited significant antioxidant efficacy.

Evaluation of myotoxic activity of Bothropstoxin-1 irradiated with 60Co gamma rays

International Nuclear Information System (INIS)

Mirco, Jessica; Baptista, Janaina A.; Caproni, Priscila; Yoshito, Daniele; Nascimento, Nanci do

2009-01-01

Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules and has been proven to be a powerful tool to attenuate snake venoms toxicity without affecting their immunogenic properties. Snake venoms and their isolated toxins showed structural modifications after gamma radiation process, in aqueous solution, mainly by water radiolysis sub products. Free radical scavengers, such as NaNO 3 and t-butanol, present selective effects on specific radical from water radiolysis. The NaNO 3 has affinity by aqueous electron, while the t-butanol has affinity by hydroxyl radical. At the present work, we have investigated the myotoxic activity of Bothropstoxin-1 (BTHX-1), a K49 phospholipase, present in Bothrops jararacussu crude venom, before and after irradiation process, with or without scavenger substances presence. BTHX-1 was irradiated with 2 kGy of 60 Co gamma rays, in aqueous solution and in the presence of oxygen. BALB/c mice were inoculated with either native or irradiated toxin, with or without scavenger substances. After 3 hours, blood samples were collected and the myotoxic activity was evaluated by LDH (lactate dehydrogenase) release. The muscular tissue damage was directly related to the LDH amounts released. Irradiated Bothropstoxin-1, with or without NaNO 3 substance, caused less damage than their native counterpart. But irradiated toxin, in the presence of t-butanol, was so myotoxic as the native BTHX-1. These results indicate that irradiation of toxic proteins can promote significant modifications on their structures, but still retaining many of the original biological properties of their native counterparts. Additionally, some scavengers substances can change these gamma radiation effects. (author)

Water radiolysis in a crack tip under gamma ray irradiation

International Nuclear Information System (INIS)

Satoh, Tomonori; Uchida, Shunsuke; Satoh, Yoshiyuki

2002-01-01

Under a non-irradiation condition, oxidant, e.g., O 2 and H 2 O 2 , in a crack tip is supplied from the bulk water. But under irradiation conditions, even if the diffusion of radiolytic species is not sufficient, direct radiolysis in the crack tip causes high concentrations of radiolytic species. As a result of measurements and Monte Carlo calculation of gamma ray energy deposition, it has been confirmed that the energy deposition rate in the gap water is larger than that in the bulk water. The energy absorption rate increases as the gap width decreases and reaches 1.3 times that in the bulk water. In order to evaluate crack propagation rate for irradiation assisted stress corrosion cracking (IASCC) of stainless steel, a water radiolysis model in a crevice is proposed. A larger energy deposition rate in the crevice water produces many more radiolytic species, which causes high oxidant concentrations in spite of enhanced recombination of the species at the crevice inner surface. So, for IASCC evaluation, crevice water chemistry plays an important role to determine the crack propagation rate under irradiation. (authors)

Shoot regeneration of callus culture from irradiated sheed of piper nigrum L by gamma rays

International Nuclear Information System (INIS)

Ishak; Hutabarat, D.

1988-01-01

Shoot regeneration was obtained from callus that induced by irradiated seed with 25 and 50 Gy of gamma-rays and then on M.S. medium containing NAA 1 ppm and 2-ip 0.5 ppm. Irradiated seed with a dose of 25 Gy produced normal root and failed to produce shoot, but rice callus. Irradiated seed with a dose of 50 Gy pruduce callus only. Shoot differentiation occured after the callus were cultured on M.S., medium containing 2-ip 1 ppm and Kinetin 2.5 ppm. (authors). 9 refs, 3 figs

biotechnological studies on the irradiated potato (solanum tuberosum) with gamma rays

International Nuclear Information System (INIS)

Hassan, I.O.I.

2011-01-01

Bacterial wilt or brown rot disease caused by Ralstonia solanacearum causes extensive annual losses of different crops especially potato crop. It is considered as one of the limiting factors for potato production and exportation in Egypt. Therefore, the main purposes of this study were to investigate the effect of gamma rays on two potato cultivars (Diamant and Spunta). And, to obtain new genotypes of potato resistant to bacterial wilt disease. This study was carried out in the field and Biotechnology laboratory of the Plant Res. Dept., Nuclear Res. Center, Inshas, Egypt and Genetics Dept., Faculty of Agricultural., Cairo Univ., during 2008-2011. In the field experiment, dry tubers of potato cultivars were irradiated by different doses of gamma rays (20, 30 and 40 Gy) to study the effect of gamma rays on the vegetative and yield traits. The results showed that there are no significant differences between cultivars for all studied traits except a number of tubers per plant trait. Also, there are only highly significant and significant differences between treatments for weight of tubers per plant and number of tubers per plant traits, respectively. However, there are only significant differences between the interactions of cultivars and treatments for plant height and weight of tubers per plant traits. Six genotypes were selected from M 1 V 2 generation depending on high yield for RAPD analysis to determine their genetic variability from its parents at molecular level using 11 primers. The results of RAPD analysis showed that 11 primers generated 56 distinct bands of which 31 (55.4%) were considered as polymorphic. The similarity indices of six genotypes of potato and its parents ranged from 70 to 91%. The highest genetic similarity 91% was found between D20 genotype and its parent D0 (Diamant control). On the other hand, the lowest genetic similarity 70% was found between S30, S40 genotypes and its parent S0 (Spunta control). In the artificial infection experiment

Response of human lymphocytes to low gamma ray doses

International Nuclear Information System (INIS)

Vega Carrillo, HR; Banuelos Valenzuela, R; Manzanares Acuna, E; Sanchez-Rodriguez, S.H

2001-01-01

Radiation and non-radiation workers lymphocytes were exposed to a low strength gamma-ray field to determine heat shock protein expression in function of radiation dose. Protein identification was carried out using mAb raised against Hsp25, Hsp60, Hsp70 and Hsp90; from these, only Hsp70 protein was detected before and after lymphocyte irradiation. In all cases, an increasing trend of relative amounts of Hsp70 in function to irradiation time was observed. After 70.5 mGy gamma-ray dose, radiation worker's lymphocytes expressed more Hsp70 protein, than non-radiation workers' lymphocytes, indicating a larger tolerance to gamma rays (gamma tolerance), due to an adaptation process developed by their labor condition (Au)

The effects of prenatal irradiation with a low doses of gamma-rays on spatial memory in adult rats

International Nuclear Information System (INIS)

Tomasova, L.; Smajda, B.

2008-01-01

Pregnant females of Wistar-strain rats were irradiated (sham-irradiated) with a dose of 1 Gy of gamma-rays on the 16 th day of pregnancy. The progeny of both irradiated and control animals was tested in Morris' water maze for spatial memory at age of 4 months. The time needed to find the hidden platform and the swimming-track were recorded using a computer aided video-tracking method. The test was repeated after 24 hours (short-time memory) and after one week (long-time memory). In short-time memory test the irradiated females needed in comparison with controls a statistically significantly longer time and a longer swimming track to find the platform. No significant differences were found in male. In long-term memory test no significant differences in both parameters followed were found in either of sexes. The results suggest, that irradiation with a low dose of gamma-rays during the period of the embryonic development of the brain can negatively influence the short-term spatial memory, but has no effect on long-time memory in rats. (authors)

Effects of gamma irradiation on deteriorated paper

Science.gov (United States)

Bicchieri, Marina; Monti, Michela; Piantanida, Giovanna; Sodo, Armida

2016-08-01

Even though gamma radiation application, also at the minimum dosage required for disinfection, causes depolymerization and degradation of the paper substrate, recently published papers seemed, instead, to suggest that γ-rays application could be envisaged in some conditions for Cultural Heritage original documents and books. In some of the published papers, the possible application of γ-rays was evaluated mainly by using mechanical tests that scarcely reflect the chemical modifications induced in the cellulosic support. In the present article the effect of low dosage γ-irradiation on cellulosic substrates was studied and monitored applying different techniques: colorimetry, spectroscopic measurements, carbonyl content and average viscometric degree of polymerization. Two different papers were investigated, a non-sized, non-filled cotton paper, and a commercial permanent paper. To simulate a real deteriorated document, which could need γ-rays irradiation, some samples were submitted to a hydrolysis treatment. We developed a treatment based on the exposition of paper to hydrochloric acid vapors, avoiding any contact of the samples with water. This method induces a degradation similar to that observed on original documents. The samples were then irradiated with 3 kGy γ-rays at a 5258 Gy/h rate. The aforementioned analyses were performed on the samples just irradiated and after artificial ageing. All tests showed negative effects of gamma irradiation on paper. Non-irradiated paper preserves better its appearance and chemical properties both in the short term and after ageing, while the irradiated samples show appreciable color change and higher oxidation extent. Since the Istituto centrale restauro e conservazione patrimonio archivistico e librario is responsible for the choice of all restoration treatments that could be applied on library and archival materials under the protection of the Italian State (http://www.icpal.beniculturali.it/allegati/DM-7

Topological and morphological analysis of gamma rays irradiated chitosan-poly (vinyl alcohol) blends using atomic force microscopy

Science.gov (United States)

Bhatt, Rinkesh; Bisen, D. S.; Bajpai, R.; Bajpai, A. K.

2017-04-01

In the present communication, binary blends of poly (vinyl alcohol) (PVA) and chitosan (CS) were prepared by solution cast method and the roughness parameters of PVA, native CS and CS-PVA blend films were determined using atomic force microscopy (AFM). Moreover, the changes in the morphology of the samples were also investigated after irradiation of gamma rays at absorbed dose of 1 Mrad and 10 Mrad for the scanning areas of 5×5 μm2, 10×10 μm2 and 20×20 μm2. Amplitude, statistical and spatial parameters, including line, 3D and 2D image profiles of the experimental surfaces were examined and compared to un-irradiated samples. For gamma irradiated CS-PVA blends the larger waviness over the surface was found as compared to un-irradiated CS-PVA blends but the values of average roughness for both the films were found almost same. The coefficient of skewness was positive for gamma irradiated CS-PVA blends which revealed the presence of more peaks than valleys on the blend surfaces.

Gamma-irradiation of tomatoes

International Nuclear Information System (INIS)

Tencheva, S.; Todorov, S.

1975-01-01

The influence of gamma-ray on tomatoes picked in a pink-red ripening stage, good for consumption, is studied. For that purpose tomatoes of ''Pioneer 2'' variety packed in perforated 500 g plastic bags were irradiated on a gamma device (Cobalt-60) at a dose power of 1900 rad/min with doses 200 or 300 krad. Samples were stored after irradiation at room temperature (20 - 22sup(o)C). Microbiological studies demonstrated that 44 resp. 99.96 per cent of the initial number of microorganisms was destroyed after irradiation with 200 resp. 300 krad. The time required for the number of microorganisms to be restored was accordingly increased. Irradiation delayed tomato ripening by 4 to 6 days, demonstrable by the reduced content of the basic staining substances - carotene and licopine. Immediately after irradiation the ascorbic acid content was reduced by an average of 13 per cent. After 18 days the amount of ascorbic acid in irradiated tomatoes was increased to a higher than the starting level, this is attributed to reductone formation during irradiation. The elevated total sugar content shown to be invert sugar was due to further tomato ripening. (Ch.K.)

Delignification of Sawdust White Teak (Gmelina arborea Roxb. by Fungi Phanerochaete chrysosporium Irradiated Gamma Ray

Directory of Open Access Journals (Sweden)

Nurhasni Nurhasni

2016-12-01

, pretreatment of substrate wood white teak (Gmelina arborea Roxb. Using a solution of NaOH 1% and H2SO4 1% and gamma-ray irradiation Co-60, have the power of ionization is small, high penetrating power, and Co-60 which can emit gamma rays a short half-life time. This research was conducted in two stages, the first stage of determining the optimum dose gamma irradiation for fungi Phanerochaete chrysosphorium (0 Gy, 200 Gy, 400 Gy, 600 Gy, 800 Gy, and 1000 Gy and the second stage of the analysis of the characteristics of the substrate wood white teak has been in pretreatment by methode Solid State Fermentation (SSF for 21 days. The results showed that the optimum dose administration of gamma irradiation on fungi Phanerochaete chrysosphorium is a dose of 600 Gy which can increase the activity of enzymes lignin peroxidase (LiP amounted to 22.18 U / mL. Chemical pretreatment process using H2SO4 1% biodelignification can accelerate the process of lignin degradation that produces the highest efficiency of 25.65%.   Keywords: Lignocellulose, delignification, Solid State Fermentation (SSF, Phanerochaete chrysosporium, gamma irradiation. DOI: http://dx.doi.org/10.15408/jkv.v0i0.3079

Evaluation of components of X-ray irradiated 7-valent pneumococcal conjugate vaccine and pneumococcal vaccine polyvalent and X-ray and gamma-ray irradiated acellular pertussis component of DTaP vaccine products

International Nuclear Information System (INIS)

May, J.C.; Rey, L.; Lee, C.-J.; Arciniega, Juan

2004-01-01

Samples of pneumococcal vaccine polyvalent, 7-valent pneumococcal conjugate vaccine, and two different diphtheria and tetanus toxoids and acellular pertussis vaccines adsorbed were irradiated with X-rays and/or gamma-rays (Co-60). Mouse IgG and IgM antibody responses (ELISA) for types 9V, 14, 18C, and 19F pneumococcal polysaccharides and conjugates indicated that the polysaccharides were more tolerant of the radiation than the conjugates. The mouse antibody response for the detoxified pertussis toxin (PT) antigen, filamentous hemagglutinin antigen (FHA), pertactin (PRN), and fimbriae types 2 and 3 (FIM) antigens for the appropriate vaccine type indicated that the antibody response was not significantly changed in the 25 kGy X-ray irradiated vaccines frozen in liquid nitrogen compared to the control vaccine

Evaluation of components of X-ray irradiated 7-valent pneumococcal conjugate vaccine and pneumococcal vaccine polyvalent and X-ray and gamma-ray irradiated acellular pertussis component of DTaP vaccine products

Energy Technology Data Exchange (ETDEWEB)

May, J.C. E-mail: may@cber.fda.gov; Rey, L. E-mail: louis.rey@bluewin.ch; Lee, C.-J.; Arciniega, Juan

2004-10-01

Samples of pneumococcal vaccine polyvalent, 7-valent pneumococcal conjugate vaccine, and two different diphtheria and tetanus toxoids and acellular pertussis vaccines adsorbed were irradiated with X-rays and/or gamma-rays (Co-60). Mouse IgG and IgM antibody responses (ELISA) for types 9V, 14, 18C, and 19F pneumococcal polysaccharides and conjugates indicated that the polysaccharides were more tolerant of the radiation than the conjugates. The mouse antibody response for the detoxified pertussis toxin (PT) antigen, filamentous hemagglutinin antigen (FHA), pertactin (PRN), and fimbriae types 2 and 3 (FIM) antigens for the appropriate vaccine type indicated that the antibody response was not significantly changed in the 25 kGy X-ray irradiated vaccines frozen in liquid nitrogen compared to the control vaccine.

Adhesion of thymus lymphocytes to aortic endothelial cells in rats irradiated with sup 60 Co-. gamma. -rays

Energy Technology Data Exchange (ETDEWEB)

Yongjian, Geng; Zijun, Mao; Zhiwei, Yin [Suzhou Medical Coll., JS (China)

1990-03-01

Adhesion of thymus lymphocytes to aortic endothelial cells in Wistar rats irradiated with {sup 60}Co-{gamma}-rays was preliminarily investigated with a stereological method. The results of experiments suggest that the number of lymphocytes of thymus which adhered to aortic endothelial cells significantly (p < 0.01) decreased after irradiation at doses of 2 and 8 Gy. However, when both thymus and aorta were irradiated, there were more lymphocytes adhering to endothelial cells than that when only thymus was irradiated.

Effects of Acute Gamma Irradiation on Amaryllis Orange Bio gamma

International Nuclear Information System (INIS)

Sakinah Ariffin; Shakinah Salleh; Shuhaimi Shamsuddin; Suhaimi Musa; Affrida Abu Hassan

2016-01-01

Ornamental and landscaping plants have their own demand. Color variations, shape and flower shelf life are among the important value-added characters in improvement of new varieties of ornamental plants. Mutation induction using ionizing radiation is an alternative way for obtaining plant with desirable traits. Improvement of ornamental plant Amaryllis 'Orange Bio gamma' was carried out by exposing bulbs with gamma rays at dose 0, 10, 15, 20, 25, 30, 40 and 50 Gy using Bio Beam GM8000 gamma irradiation chamber at the Malaysian Nuclear Agency. Effect of radiation on the growth of bulbs was observed. Data on shoot and root length was recorded after 6 weeks. From the observation, the increasing dose has caused a reduction in shoot length and inhibited the root production. This paper will discuss the effects of acute gamma irradiation on the plant morphology. The result and observation obtained is useful for future work on lily improvement and will be included into Bio Beam GM8000 irradiation database. (author)

Identification of Morphological Character and Esterase Isozyme Pattern in Second-Generation Black Rice Plant Irradiated to Gamma Rays

Science.gov (United States)

Hartanti, R. S.; Putri, T. A. N.; Zulfa, F.; Sutarno; Suranto

2017-04-01

Black rice is one of the functional foods due to its high anthocyanin content. Black rice grain was irradiated by gamma rays with a dose of 200 Gy and 300 Gy. The main purpose of this irradiation is to induce mutation to the black rice plant in order to achieve the improved organism. This study was undertaken to elucidate the morphological character and esterase isozyme pattern of black rice plant after irradiated by gamma rays. There were morphological differences on leaves, stems and grains between irradiated and non irradiated black rice plant. Gamma radiation dose of 200 Gy showed the significant influence of the length of the stem, number of internodes, and length of leaves. The radiation dose of 300 Gy showed the significant influence of the decrease value of diameter of 3rd internodes, number of branches and width of leaves. Flowering time is getting faster as increasing radiation dose. At the age of 74 days after planting there are 9.15% plants of 200 Gy radiation dose that have flowered faster than normal plants. This value increased into 11.45% at the dose of radiation 300 Gy. There were differences in the esterase banding pattern between radiation dose of 200 Gy and 300 Gy than the control plants, indicated that randomly mutation has occurred.

Thermoplastic Elastomers From Chemically or Irradiation Activated Polyolefin Wastes and Ground Tyre Rubber

International Nuclear Information System (INIS)

Tolstov, A.M.; Grigoryeva, A.L.; Bardash, O.P.

2005-01-01

Thermoplastic elastomers (TPE) are known as materials with unique combination of elastomeric properties and thermo plasticity. Among the TPE of different type the polymer blends of thermoplastics and rubbers are the most commonly used. Recently a very effective technology of dynamic vulcanization of rubber component inside thermoplastic matrix has been developed. As a result of rubber vulcanization and dispersion inside thermoplastic the new type of TPE so-called thermoplastic dynamic vulcanizations (TPV) are obtained. In our work we have applied the technology of dynamic vulcanization for recycled components (PP, HDPE, GTR). It has appeared that such components are not mixed well and the resulting TPV have poor mechanical properties. To solve a problem of poor compatibility of the components used we carried out a pre-modification (functionalization) of the component surfaces by gamma-irradiation or by chemically or gamma-irradiation induced grafting of reactive monomers. Both the polyolefin (HDPE) and GTR were functionalized before mixing. The monomers were selected by such a way that being grafted to be able to react to each other in interface during the components blending. For example, we used maleic anhydride and acrylamide. The effect of better compatibility has appeared in higher tensile characteristics of TPV synthesized

Evaluation of time-accelerated irradiation method of elastomer by modulus-ultimate elongation profile

International Nuclear Information System (INIS)

Ito, Masayuki; Oka, Toshitaka; Hama, Yosimasa

2009-01-01

'Generalized modulus-ultimate elongation profile' was induced from the relationship between the modulus and the ultimate elongation of an elastomer that was quantitatively added crosslinking and scission. This profile can be used to evaluate the time-accelerated irradiation methods of ethylene-propylene-diene elastomer. The irradiation under low dose rate (0.33 kGy/h) at room temperature was the reference condition. The short-time irradiation condition was 4.2 kGy/h in 0.5 MPa oxygen at room temperature and 5.0 kGy/h in air at 70 o C. The former tended to bring about the higher ratio of scission than the reference condition; the latter tended to bring about the higher ratio of crosslinking.

Perna perna (LINNAEUS, 1758) mussels irradiated by {sup 60}CO gamma rays cytotoxicity evaluation

Energy Technology Data Exchange (ETDEWEB)

Martini, Gisela A.; Pusceddu, Fabio H.; Rogero, Sizue O.; Rogero, Jose Roberto, E-mail: gisela.martini@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

The aim of the present work was the study of ionizing radiation effects on aquatic biota regarding the location of nuclear facilities nearby coastal areas assuming the risk of leaks and nuclear accidents. Bivalve mollusks have been widely used in the monitoring of aquatic environment studies mainly for their sessile habit and pollutants bioconcentration ability. So marine mussel Perna perna (Bivalvia: Mytilidae) was used as organism test in this study. The study of radioactive toxicity was performed by cytotoxicity test exposing the organisms to 11Gy gamma radiation dose. After radiation the neutral red retention assay evaluated the lysosomal membrane integrity in the mussel hemocytes. 50% lethal dose assay (LD50) of gamma radiation on Perna perna mussels was carried out by exposure the organisms to {sup 60}Co gamma rays at doses ranging from 0 to 3000 Gy. The result of gamma radiation LD50 for these mussels was 1068 Gy and the neutral red retention time of irradiated organisms was about 47% lower than the control, non irradiated organisms. With the obtained results is expected to contribute in the study to identify the range of ionizing radiation doses which can cause toxic effects in marine invertebrates. (author)

Gamma ray induced chromophore modification of softwood thermomechanical pulp

International Nuclear Information System (INIS)

Robert, S.; Daneault, C.; Viel, C.; Lepine, F.

1992-01-01

This study focuses on bleaching a softwood (black spruce, balsam fur) thermomechanical pulp with gamma rays. Gamma rays are known for their enormous penetrating power, along with their ionizing properties. They can generate highly energetic radicals capable of oxidizing lignin chromophores. The authors studied the influence of isopropyl alcohol, sodium borohydride, oxygen, hydrogen peroxide, nitrogen dioxide and water along with gamma ray irradiation of the pulps. The authors measured the optimal dose and dose rate, along with the influence of the radical scavengers like oxygen on the bleaching effect of gamma irradiated pulps. They observe various degrees of bleaching of these pulps. Evidence relates this bleaching to the generation of perhydroxyl anions upon irradiation of water. Also, they were able to pinpoint the influence of the dose rate on the rate of formation and disappearance of these perhydroxyl anions and their influence on bleaching kinetics. Stability toward photoyellowing, and photoyellowing's kinetic of papers from these pulps was also studied

Tolerance of edible flowers to gamma irradiation

International Nuclear Information System (INIS)

Koike, Amanda C.R.; Araujo, Michel M.; Costa, Helbert S.F.; Almeida, Mariana C.; Villavicencio, Anna Lucia C.H.

2011-01-01

People have been eating flowers and using them in culinary creations for hundreds of years. Edible flowers are increasingly being used in meals as an ingredient in salads or garnish, entrees, drinks and desserts. The irradiation process is an alternative method that can be used in disinfestation of food and flowers, using doses that do not damage the product. The sensitivity of flowers to irradiation varies from species to species. In the present research was irradiated with doses up to 1 kGy some edible flowers to examine their physical tolerance to gamma-rays. Furthermore, high doses gamma irradiation causes petal withering, browning process and injury in edible flowers. (author)

Tolerance of edible flowers to gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Koike, Amanda C.R.; Araujo, Michel M.; Costa, Helbert S.F.; Almeida, Mariana C.; Villavicencio, Anna Lucia C.H., E-mail: ackoike@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil)

2011-07-01

People have been eating flowers and using them in culinary creations for hundreds of years. Edible flowers are increasingly being used in meals as an ingredient in salads or garnish, entrees, drinks and desserts. The irradiation process is an alternative method that can be used in disinfestation of food and flowers, using doses that do not damage the product. The sensitivity of flowers to irradiation varies from species to species. In the present research was irradiated with doses up to 1 kGy some edible flowers to examine their physical tolerance to gamma-rays. Furthermore, high doses gamma irradiation causes petal withering, browning process and injury in edible flowers. (author)

Tumor induction in mice after local irradiation with single doses of either carbon-ion beams or gamma rays.

Science.gov (United States)

Ando, Koichi; Koike, Sachiko; Ohmachi, Yasushi; Ando, Yutaka; Kobashi, Gen

2014-12-01

To determine the dose-dependent relative biological effectiveness (RBE) for tumor prevalence in mice receiving single localized doses to their right leg of either carbon ions (15, 45 or 75 keV/μm) or 137Cs gamma rays. A total of 1647 female C3H mice were irradiated to their hind legs with a localized dose of either reference gamma rays or 15, 45 or 75 keV/μm carbon-ion beams. Irradiated mice were evaluated for tumors twice a month during their three-year life span, and the dimensions of any tumors found were measured with a caliper. The tumor induction frequency was calculated by Kaplan-Meier analysis. The incidence of tumors from 50 Gy of 45 keV/μm carbon ions was marginally higher than those from 50 Gy of gamma rays. However, 60 Gy of 15 keV/μm carbon ions induced significantly fewer tumors than did gamma rays. RBE values of 0.87 + 0.12, 1.29 + 0.08 or 2.06 + 0.39 for lifetime tumorigenesis were calculated for 15, 45 or 75 keV/μm carbon-ion beams, respectively. Fibrosarcoma predominated, with no Linear Energy Transfer (LET)-dependent differences in the tumor histology. Experiments measuring the late effect of leg skin shrinkage suggested that the carcinogenic damage of 15 keV/μm carbon ions would be less than that of gamma rays. We conclude that patients receiving radiation doses to their normal tissues would face less risk of secondary tumor induction by carbon ions of intermediate LET values compared to equivalent doses of photons.

Physiological characteristics of cucumber seed production plants by presowing laser and gamma irradiation

International Nuclear Information System (INIS)

Cholakov, D.; Petkova, V.

1994-01-01

Seeds from G-3 maternal line of hybrid cucumber cultivar Pobeda F 1 were treated with helium-neon 632.8 nm laser-exit power 20 mW and gamma-rays ( 60 Co) in a field experiment under conditions suitable for hybrid seed production. The irradiation was carried out a week before sowing and the following variants were investigated: 1. sevenfold laser irradiation; 2. 10 Gy gamma irradiation; 3. combined laser + gamma rays irradiation. Seeds from the parent line were not irradiated. A positive effect of irradiation on the photosynthetic intensity, content of plastid pigments in leaves and activity of catalase and peroxidase has been observed. (author)

Alteration of Leaf Anatomy of Handeuleum (Graptophyllum pictum L. Griff due to Gamma Irradiation

Directory of Open Access Journals (Sweden)

Arrin Rosmala

2016-07-01

Full Text Available The leaves of the plant handeuleum (Graptophyllum pictum L. Griff have long been used for traditional medicine in several regions in Indonesia. This study was aimed to determine the effect of gamma irradiation rate on the anatomy and phytochemical content of the leaf. The rates of gamma rays used were 0, 15, 30, 45, 60, 75, 90, and 105 Gy. Our results showed that gamma ray irradiation rate of 30 Gy produced leaves that contain anthocyanins and carotenoids, with the highest number of stomata and stomatal density compared with control plants. Stomatal index was found highest in the leaves with 45 Gy of gamma irradiation. High-rate gamma ray irradiation produced rigid, thick, and frangible leaves. A high rate of gamma irradiation, i.e. 75, 90, and 105 Gy, produces bigger palisade, sponges, and upper epidermis than the control plants, respectively. Our results showed an association between increasing rate of irradiation with alterations in the structure of leaf anatomy and phytochemical content of handeuleum.

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

International Nuclear Information System (INIS)

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

1978-01-01

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

Single-Event Effects in Power MOSFETs During Heavy Ion Irradiations Performed After Gamma-Ray Degradation

Science.gov (United States)

Busatto, G.; De Luca, V.; Iannuzzo, F.; Sanseverino, A.; Velardi, F.

2013-10-01

The robustness of commercial power metal-oxide semiconductor field-effect transistors to combined gamma-heavy ion irradiation has been investigated, evidence that the degradation of the gate oxide caused by the γ irradiation can severely corrupt the robustness to single-event effects and drastically modify the physical behavior of the device under test after the impact of a heavy ion. A decrease of the critical voltages at which destructive burnouts and gate ruptures for heavy ion impact appear, has been detected in the devices under test, which were previously irradiated with γ rays. In addition, the amount of critical voltage reduction is strictly related to the amount of the absorbed γ-ray dose. Furthermore, at the failure voltage, the behavior of the device is affected by the conduction of a current through the gate oxide. Moreover, the single-event gate rupture” of the device appears at lower voltages because of the reduction of the Fowler-Nordheim limit in the γ-irradiated devices.

Use of gamma irradiation for microbial inactivation of buckwheat flour and products, 8

International Nuclear Information System (INIS)

Muramatu, Nobuyuki; Ohinata, Hiroshi; Karasawa, Hideyuki; Oike, Terutake; Ito, Hitoshi; Ishigaki, Isao.

1991-01-01

Effects of irradiation at 3.0-7.0 kGy with 2 MeV electron beams were investigated on the number of microorganisms and quality of buckwheat flour. Electron beams and gamma-rays were compared in terms of the effects on the quality of buckwheat flour. The results were as follows. (1) Electron beams at 3 kGy reduced the number of microorganisms almost to the same level as gamma-rays. Oxygen content in buckwheat flour had no effect on inactivation of microorganisms by irradiation with electron beams and gamma-rays. (2) Peroxide-value (POV) of lipid in buckwheat flour increased with absorbed dose of gamma-rays and electron beams. The increase of POV was suppressed by the usage of oxygen absorber. The color change of buckwheat flour was suppressed by the usage of oxygen absorber as well. Acid-value (AV) of lipid in buckwheat flour was not changed by irradiation at high dose with gamma-rays or electron beams. (3) Maximum torque in Farinograph test of dough prepared from irradiated buckwheat flour decreased with increase of absorbed dose of electron beams. However, oxygen absorber suppressed the change of these properties induced by irradiation. (4) The usage of oxygen absorber resulted in a high sensory score of noodles from irradiated buckwheat flour with small changes of color, flavor and texture. (author)

Comparative study on hematopoietic damage of mice caused by high-dose of gamma-ray irradiation

International Nuclear Information System (INIS)

Wu Hongying; Wang Yueying; Li Deguan; Wang Xiaochun; Zhang Heng; Lu Lu; Chang Jianhui; Du Liqing; Wang Yan; Men Aimin

2010-01-01

Objective: To study the effect of high-dose of gamma-ray irradiation on hematopoiesis injury and recovery of IRM-2 and C57BL/6 J mouse. Methods: The experiment was designed to study the effects of radiation (4 Gy) on spleen index, CFU-S and DNA damage on the 9 th day of IRM-2 and ICR mice and the effects of radiation (6 Gy) on WBC change and its absolute value on the 45 th days of IRM-2 and C57BL/6 J mice. Results: The IRM-2 mouse spleen index, CFU-S and DNA were higher than ICR mouse on the 9 th days, and there were significant difference in CFU-S and DNA (P<0.01). The IRM-2 mouse WBC, RMC, HGB and HCT were higher than C57BL/6 J mouse on the 45 th days, and there were significant difference (P<0.01). Conclusion: IRM-2 mouse hematopoiesis resumes quicker than C57BL/6 J and ICR do after high-dose of gamma-ray irradiation. (authors)

Evaluation of myotoxic activity of Bothropstoxin-1 irradiated with {sup 60}Co gamma rays

Energy Technology Data Exchange (ETDEWEB)

Mirco, Jessica; Baptista, Janaina A.; Caproni, Priscila; Yoshito, Daniele; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil)], e-mail: jessica.mirco@yahoo.com.br, e-mail: janabap@gmail.com, e-mail: pricaproni@hotmail.com, e-mail: daniyoshito@uol.com.br, e-mail: nnascime@ipen.br

2009-07-01

Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules and has been proven to be a powerful tool to attenuate snake venoms toxicity without affecting their immunogenic properties. Snake venoms and their isolated toxins showed structural modifications after gamma radiation process, in aqueous solution, mainly by water radiolysis sub products. Free radical scavengers, such as NaNO{sub 3} and t-butanol, present selective effects on specific radical from water radiolysis. The NaNO{sub 3} has affinity by aqueous electron, while the t-butanol has affinity by hydroxyl radical. At the present work, we have investigated the myotoxic activity of Bothropstoxin-1 (BTHX-1), a K49 phospholipase, present in Bothrops jararacussu crude venom, before and after irradiation process, with or without scavenger substances presence. BTHX-1 was irradiated with 2 kGy of {sup 60}Co gamma rays, in aqueous solution and in the presence of oxygen. BALB/c mice were inoculated with either native or irradiated toxin, with or without scavenger substances. After 3 hours, blood samples were collected and the myotoxic activity was evaluated by LDH (lactate dehydrogenase) release. The muscular tissue damage was directly related to the LDH amounts released. Irradiated Bothropstoxin-1, with or without NaNO{sub 3} substance, caused less damage than their native counterpart. But irradiated toxin, in the presence of t-butanol, was so myotoxic as the native BTHX-1. These results indicate that irradiation of toxic proteins can promote significant modifications on their structures, but still retaining many of the original biological properties of their native counterparts. Additionally, some scavengers substances can change these gamma radiation effects. (author)

Effects of gamma-ray radiation on activity and apoptosis of rat cardiomyocytes in vitro

International Nuclear Information System (INIS)

Hu Shunying; Jiang Changsheng; Chen Guowei; Duan Haifeng; Wang Rongliang; Wu Bin; Guo Zikuan; Wang Lisheng

2007-01-01

Objective: It is reported that radiation-induced myocardial degeneration in the rat is preceded by changes in capillary structure and function. The aim of the present study is to investigate direct effect of gamma ray radiation on activity and apoptosis of cultured rat cardiomyocytes in vitro. Methods: The study was performed using primary cell cultures of cardiomyocytes isolated from hearts of now-born rats. After being cultured for 72h in vitro, cardiomyocytes were irradiated with single dose of 5 Gy, 10 Gy, 20 Gy of gamma ray respectively. At 48h post-irradiation, the concentration of LDH in the supernatant of cell culture was tested using methods introduced by International Federation of clinical chemistry (IFCC), and apoptosis was determined with flow cytometry. The viability of myocytes was determined with crystal violet test and MTT test at 48h and 120h post-irradiation respectively. Results: LDH concentration in the supernatant of cell culture of cardiomyocytes were increased significantly with the irradiation dose augment. Flow cytometry confirmed the induction of apoptosis in response to different gamma ray doses irradiation at 48h after irradiation. The viable cardiomyocytes irradiated by gamma ray were significantly declined at 120h after irradiation compared to un-irradiated cells, however there were no significant difference between two groups at 48h post-irradiation. Dose-effect relationship was demonstrated between cardiomyocyte apoptosis, viability and irradiation dose in the study. Conclusion: The study demonstrates gamma ray radiation can cause direct damage to cultured cardiomyocytes, including inhibiting activity and inducing apoptosis of cardiomyocytes in vitro, which shows dose effect relationship. The mechanism of gamma ray irradiation induced injury to cardiomyocytes should be investigated further. (authors)

Radiosensitivity of Prostate Cancer Cell Lines for Irradiation from Beta Particle-emitting Radionuclide ¹⁷⁷Lu Compared to Alpha Particles and Gamma Rays.

Science.gov (United States)

Elgqvist, Jörgen; Timmermand, Oskar Vilhelmsson; Larsson, Erik; Strand, Sven-Erik

2016-01-01

The purpose of the present study was to investigate the radiosensitivity of the prostate cancer cell lines LNCaP, DU145, and PC3 when irradiated with beta particles emitted from (177)Lu, and to compare the effect with irradiation using alpha particles or gamma rays. Cells were irradiated with beta particles emitted from (177)Lu, alpha particles from (241)Am, or gamma rays from (137)Cs. A non-specific polyclonal antibody was labeled with (177)Lu and used to irradiate cells in suspension with beta particles. A previously described in-house developed alpha-particle irradiator based on a (241)Am source was used to irradiate cells with alpha particles. External gamma-ray irradiation was achieved using a standard (137)Cs irradiator. Cells were irradiated to absorbed doses equal to 0, 0.5, 1, 2, 4, 6, 8, or 10 Gy. The absorbed doses were calculated as mean absorbed doses. For evaluation of cell survival, the tetrazolium-based WST-1 assay was used. After irradiation, WST-1 was added to the cell solutions, incubated, and then measured for level of absorbance at 450 nm, indicating the live and viable cells. LNCaP, DU145, and PC3 cell lines all had similar patterns of survival for the different radiation types. No significant difference in surviving fractions were observed between cells treated with beta-particle and gamma-ray irradiation, represented for example by the surviving fraction values (mean±SD) at 2, 6, and 10 Gy (SF2, SF6, and SF10) for DU145 after beta-particle irradiation: 0.700±0.090, 0.186±0.050 and 0.056±0.010, respectively. A strong radiosensitivity to alpha particles was observed, with SF2 values of 0.048±0.008, 0.018±0.006 and 0.015±0.005 for LNCaP, DU145, and PC3, respectively. The surviving fractions after irradiation using beta particles or gamma rays did not differ significantly at the absorbed dose levels and dose rates used. Irradiation using alpha particles led to a high level of cell killing. The results show that the beta-particle emitter

Gamma-ray irradiation resistance of silver doped GeS2–Ga2S3–AgI chalcohalide glasses

International Nuclear Information System (INIS)

Shen, W.; Baccaro, S.; Cemmi, A.; Ren, J.; Zhang, Z.; Zhou, Y.; Yang, Y.; Chen, G.

2014-01-01

Highlights: • The γ-ray irradiation resistance of Ag doped chalcohalide glasses (GeS 2 –Ga 2 S 3 –AgI) has been investigated. • The introduction of silver ions plays a specific role in the modification of the gamma-ray irradiation resistance of glasses. • The sulfur exerts an important effect on the photo-sensitivity of chalcogenide glasses. - Abstract: In the present work, series of silver doped Ge–Ga–S–AgI chalcohalide glasses have been prepared and their optical transmission spectra are compared before and after γ-ray irradiation at different doses. The differential transmission spectra of the irradiated samples with and without Ag doping have been compared to characterize the γ-ray irradiation induced red-shift of electronic absorption and formation of color centers. Ag doping plays an important role in increasing γ-ray irradiation resistance of the chalcohalide glasses due to its specific effect on the valence band and the network structure of glasses

BROCCOLI Spears Yield Affected By GAMMA Rays Irradiated Seeds And Foliar Application Of Some Growth Regulators

International Nuclear Information System (INIS)

ABDALLAH, A.A.; ABO EL-KHEIR, O.H.

2010-01-01

Two field experiments were carried out during 2004/2005 and 2005/2006 winter growing seasons at the experimental farm of Nuclear Research Centre, Atomic Energy Authority, Inshas, Egypt.The experiments were conducted to study the effect of pre-sowing broccoli seeds (cv. F1 175) irradiated with different doses of gamma rays (2, 3 and 4 Gy). The plants were sprayed with GA3 at rate of 50 ml/liter/fed and 20 ml/liter/fed for NAA. Main spear fresh and dry weight per plant, total spears fresh and dry weight per plant, total spears yield, ascorbic acid, TSS, carbohydrates, total chlorophyll, NPK and total protein content of spears were evaluated. The results showed that broccoli seeds irradiated with gamma rays up to 4 Gy pre-sowing increased the abovementioned parameters with different magnitudes comparing with the non-irradiated control plants except spears N, P and protein contents showed decrease in their values comparing with un-treated plants.It could be concluded that the foliar application of GA3 and NAA on broccoli spears increased all the abovementioned parameters, except spears N, P and protein contents showed decrease in their values.

Comparative effect of mutation of Aspergillus oryzae by gamma or ultraviolet irradiation

International Nuclear Information System (INIS)

Ito, Hitoshi; Nessa, A.

1994-01-01

Mutation frequency of Aspergillus oryzae IAM2630 was studied compared with gamma and ultraviolet irradiation. In this study, mutation frequency of morphological changes on survived colonies was increased up to 50% by irradiation of gamma-rays at survival fraction of 10 -3 to 10 -4 on potato-dextrose agar. On the contrary, mutation frequency of ultraviolet was obtained less than 17% at survival fraction of 10 -3 . Mutants with improvement of three-to-five hold production of α-amylase were isolated by irradiation of gamma-rays at 1.2 kGy. However, we could not isolate any mutants of higher production of α-amylase by ultraviolet irradiation. (author)

Comparative effect of mutation of Aspergillus oryzae by gamma or ultraviolet irradiation

Energy Technology Data Exchange (ETDEWEB)

Ito, Hitoshi; Nessa, A. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

1994-08-01

Mutation frequency of Aspergillus oryzae IAM2630 was studied compared with gamma and ultraviolet irradiation. In this study, mutation frequency of morphological changes on survived colonies was increased up to 50% by irradiation of gamma-rays at survival fraction of 10{sup -3} to 10{sup -4} on potato-dextrose agar. On the contrary, mutation frequency of ultraviolet was obtained less than 17% at survival fraction of 10{sup -3}. Mutants with improvement of three-to-five hold production of {alpha}-amylase were isolated by irradiation of gamma-rays at 1.2 kGy. However, we could not isolate any mutants of higher production of {alpha}-amylase by ultraviolet irradiation. (author).

Effect of cobalt-60 gamma-ray irradiation on beans (Phaseolus vulgaris L.) of huasteco variety

International Nuclear Information System (INIS)

Navarro A, W.

1984-01-01

Bean seeds, Huasteco variety, were irradiated at 10, 20, 30 and 40 kR in a cobalt-60 gamma-ray source. Non-irradiated seeds were used as control. Irradiated and non-irradiated seeds were planted under greenhouse conditions using a random design and a population of 200 plants per treatment for both first and second generations (M 1 and M 2 ). The characters studied were; germination, survival, morphological changes of leaves and stem, change in seed coat colour, flowering, height, stem diameter, number of internodes, number of pods and number of seeds per pod. General plant behaviour was also observed to detect changes on a genic or chromosomic level. (M.A.C.) [pt

Study of stability of humic acids from soil and peat irradiated by gamma rays

International Nuclear Information System (INIS)

Silva, Wilson Tadeu Lopes da

1995-01-01

Humic acids samples (one deriving from a sedimentary soil and other from a peat), in aqueous media, were irradiated with gamma rays, in doses of 10, 50 and 100 kGy, in order to understand their chemical behavior after the irradiation. The material, before and after irradiation, was analyzed by Elemental Analysis, Functional Groups (carboxylic acids and phenols), UV/Vis Spectroscopy (E 4 /E 6 ratio), IR spectroscopy, CO 2 content and Gel permeation Chromatography (GPC) ). The Elemental Analysis showed the humic acid derived from a peat had a most percentage quantity of Carbon and Hydrogen than the material from a sedimentary soil. From the UV/Vis Spectroscopy, it was observed a decrease of E 4 /E 6 ratio with an increase of the applied dose. The data from GPC are in agreement with this. The results showed that the molecular weight of the material increased by exposing it to a larger radiolitical dose. The peat material was less affected by the gamma radiation than the soil material. The carboxylic groups were responsible by radiochemical behavior of the material. (author)

Effect of gamma irradiation on HPMC/ZnO nanocomposite films

International Nuclear Information System (INIS)

Rao, B. Lakshmeesha; Asha, S.; Madhukumar, R.; Latha, S.; Gowda, Mahadeva; Shivananda, C. S.; Harish, K. V.; Sangappa; Shetty, G. Rajesha

2015-01-01

The present work looks into the structural and mechanical properties modification in ZnO nanoparticle incorporated Hydroxypropyl methylcellulose (HPMC) polymer films, induced by gamma irradiation. The irradiation process was performed in gamma chamber at room temperature by use of Cobalt-60 source (Average energy of 1.25MeV) at different doses: 0, 50, 100, 150 and 200 kGy respectively. The changes in structural parameters and mechanical properties in pure and gamma irradiated HPMC/ZnO nanocomposite films have been studied using X-ray scattering (XRD) data and universal testing machine (UTM). It is found that gamma irradiation decreases the structural parameters and improves the mechanical properties of nanocomposite films

High gamma-rays irradiation tests of critical components for ITER (International Thermonuclear Experimental Reactor) in-vessel remote handling system

International Nuclear Information System (INIS)

Obara, Kenjiro; Kakudate, Satoshi; Oka, Kiyoshi

1999-02-01

In ITER, the in-vessel remote handling is inevitably required to assemble and maintain the activated in-vessel components due to deuterium and tritium operation. Since the in-vessel remote handling system has to be operated under the intense of gamma ray irradiation, the components of the remote handling system are required to have radiation hardness so as to allow maintenance operation for a sufficient length of time under the ITER in-vessel environments. For this, the Japan, European and Russian Home Teams have extensively conducted gamma ray irradiation tests and quality improvements including optimization of material composition through ITER R and D program in order to develop radiation hard components which satisfy the doses from 10 MGy to 100 MGy at a dose rate of 1 x 10 6 R/h (ITER R and D Task: T252). This report describes the latest status of radiation hard component development which has been conducted by the Japan Home Team in the ITER R and D program. The number of remote handling components tested is about seventy and these are categorized into robotics (Subtask 1), viewing system (Subtask 2) and common components (Subtask 3). The irradiation tests, including commercial base products for screening, modified products and newly developed products to improve the radiation hardness, were carried out using the gamma ray irradiation cells in Takasaki Establishment, JAERI. As a result, the development of the radiation hard components which can be tolerable for high temperature and gamma radiation has been well progressed, and many components, such as AC servo motor with ceramics insulated wire, optical periscope and CCD camera, have been newly developed. (author)

High gamma-rays irradiation tests of critical components for ITER (International Thermonuclear Experimental Reactor) in-vessel remote handling system

Energy Technology Data Exchange (ETDEWEB)

Obara, Kenjiro; Kakudate, Satoshi; Oka, Kiyoshi [Department of Fusion Engineering Research, Naka Fusion Research Establishment, Japan Atomic Energy Research Institute, Naka, Ibaraki (Japan)] [and others

1999-02-01

In ITER, the in-vessel remote handling is inevitably required to assemble and maintain the activated in-vessel components due to deuterium and tritium operation. Since the in-vessel remote handling system has to be operated under the intense of gamma ray irradiation, the components of the remote handling system are required to have radiation hardness so as to allow maintenance operation for a sufficient length of time under the ITER in-vessel environments. For this, the Japan, European and Russian Home Teams have extensively conducted gamma ray irradiation tests and quality improvements including optimization of material composition through ITER R and D program in order to develop radiation hard components which satisfy the doses from 10 MGy to 100 MGy at a dose rate of 1 x 10{sup 6} R/h (ITER R and D Task: T252). This report describes the latest status of radiation hard component development which has been conducted by the Japan Home Team in the ITER R and D program. The number of remote handling components tested is about seventy and these are categorized into robotics (Subtask 1), viewing system (Subtask 2) and common components (Subtask 3). The irradiation tests, including commercial base products for screening, modified products and newly developed products to improve the radiation hardness, were carried out using the gamma ray irradiation cells in Takasaki Establishment, JAERI. As a result, the development of the radiation hard components which can be tolerable for high temperature and gamma radiation has been well progressed, and many components, such as AC servo motor with ceramics insulated wire, optical periscope and CCD camera, have been newly developed. (author)

Effect of gamma irradiation on Korean traditional multicolored paintwork

Science.gov (United States)

Yoon, Minchul; Kim, Dae-Woon; Choi, Jong-il; Chung, Yong-Jae; Kang, Dai-Ill; Hoon Kim, Gwang; Son, Kwang-Tae; Park, Hae-Jun; Lee, Ju-Woon

2015-10-01

Gamma irradiation can destroy fungi and insects involved in the bio-deterioration of organic cultural heritages. However, this irradiation procedure can alter optical and structural properties of historical pigments used in wooden cultural heritage paintings. The crystal structure and color centers of these paintings must be maintained after application of the irradiation procedure. In this study, we investigated the effects of gamma irradiation on Korean traditional multicolored paintwork (Dancheong) for the preservation of wooden cultural heritages. The main pigments in Korean traditional wooden cultural heritages, Sukganju (Hematite; Fe2O3), Jangdan (Minium; Pb3O4), Whangyun (Crocoite; PbCrO4), and Jidang (Rutile; TiO2), were irradiated by gamma radiation at doses of 1, 5, and 20 kGy. After irradiation, changes in Commision Internationale d'Eclairage (CIE) color values (L*, a*, b*) were measured using the color difference meter, and their structural changes were analyzed using X-ray diffraction (XRD) analysis. The slightly change in less than 1 dE* unit by gamma irradiation was observed, and structural changes in the Dancheong were stable after exposure to 20 kGy gamma irradiation. In addition, gamma irradiation could be applied to painted wooden cultural properties from the Korean Temple. Based on the color values, gamma irradiation of 20 kGy did not affect the Dancheong and stability was maintained for five months. In addition, the fungicidal and insecticidal effect by less than 5 kGy gamma irradiation was conformed. Therefore, the optical and structural properties of Dancheong were maintained after gamma irradiation, which suggested that gamma irradiation can be used for the preservation of wooden cultural heritages painted with Dancheong.

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

International Nuclear Information System (INIS)

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

1994-10-01

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

Protective effects of vitamin C against gamma-ray induced wholly damage and genetic damage

International Nuclear Information System (INIS)

Fu Chunling; Jiang Weiwei; Zhang Ping; Chen Xiang; Zhu Shengtao

2000-01-01

Objective: Protective effects of supplemental vitamin C against 60 Co-gamma-ray induced wholly damage and genetic damage was investigated in mice. Method: Mice were divided into normal control group, irradiation control group and vitamin C experimental group 1,2,3 (which were orally given vitamin C 15, 30, 45 mg/kg.bw for 10 successive days respectively prior to gamma-ray irradiation). Micronuclei in the bone marrow polychromatophilic erythrocytes in each group of mice were examined and the 30 day survival rate of mice following whole-body 5.0 Gy γ irradiation were also determined. Results: Supplemental vitamin C prior to gamma-rays irradiation can significantly decrease bone marrow PECMN rate of mice and increase 30 day survival rate and prolong average survival time. The protection factor is 2.09. Conclusion: Vitamin C has potent protective effects against gamma irradiation induced damage in mice. In certain dose range, vitamin C can absolutely suppress the gamma-rays induced genetic damage in vivo

The characteristics of epoxy resin cured by {gamma}-ray and E-beam

Energy Technology Data Exchange (ETDEWEB)

Nho, Y.C. E-mail: ycnho@kaeri.re.kr; Kang, Phil Hyun; Park, Jong Seok

2004-10-01

Epoxy resins are widely used as high-performance thermosetting resins for many industrial applications. In this study, the effect of an electron beam (E-beam) and {gamma}-ray irradiation on the curing of epoxy resins was investigated. Diglycidyl ether of bisphenol-A(DGEBA), diglycidyl ether of bisphenol-F(DGEBF) as epoxy resins, triarylsulfonium hexafluoroantimonate(TASHFA), and triarylsulfonium hexafluorophosphate(TASHFP) as initiators were used in this study. The chemical and mechanical characteristics of irradiated epoxy resins were compared after curing of E-beam and {gamma}-ray irradiation up to 50 kGy in N{sub 2} and air atmosphere. We ascertained the effect of oxygen on the radiation curing of epoxy resin. The thermal properties of cured epoxy were investigated using DMA and TGA. Mechanical properties such as flexural strength were measured. The chemical structures of cured epoxy were characterized by FT-NIR. The gel fraction and the stress at yield of epoxy resins irradiated by E-beam and {gamma}-ray in N{sub 2} atmosphere were also compared with those of epoxy resins irradiated by E-beam and {gamma}-ray in air.

Dose-response of photographic emulsions under gamma irradiation

International Nuclear Information System (INIS)

Tran Dai Nghiep; Do Thi Nguyet Minh; Le Van Vinh

2003-01-01

Photographic emulsion is irradiated under gamma rays irradiation of 137 Cs in the IAEA/WHO secondary standard dosimetry laboratory. Dose-response of the film is established. The sensitivity of the film is determined. The dose-rate effect is studied. (author)

Activation of immune functions via induction of glutathione of lymphocytes by low-dose, whole-body irradiation with gamma-rays

International Nuclear Information System (INIS)

Shuji Kojima; Hisatake Hayase; Mareyuki Takahashi

2007-01-01

Complete text of publication follows. We have recently found that low doses of radiation, unlike higher doses, do not always cause a decrease of cellular glutathione, but they can increase it, leading to an elevation of Con A-induced proliferation of splenocytes. In this study, we first examined whether the increase of glutathione level induced by low-dose gamma-ray irradiation is involved in the appearance of enhanced natural killer (NK) activity and antibody-dependent cellular cytotoxicity (ADCC), leading to delayed tumor growth in Ehrlich solid tumor (EST)-bearing mice. NK activity in ICR mouse splenocytes was significantly increased from 4 h to 6 h after a single whole-body gamma-ray irradiation at 0.5 Gy, and thereafter decreased almost to the zero-time level by 24 h post-irradiation. ADCC was also increased significantly in a similar way. Reduced glutathione exogenously added to splenocytes obtained from normal mice enhanced both NK activity and ADCC in a dose-dependent manner. The inhibitory effect of the radiation on tumor growth was then examined in EST-bearing mice. Repeated low-dose irradiation (0.5 Gy, four times, before and within an early time after the inoculation) significantly delayed the tumor growth. Finally, the effect of single low-dose (0.5 Gy), whole-body gamma-ray irradiation on immune balance (Th1/Th2) was examined in order to elucidate the mechanism underlying the anti-tumor immunity. Recent studies indicate that Th1/Th2 balance plays an important role in the immune responses involved in anti-tumor immunity. The activity of NK is hallmarks of cell-mediated immunity, and play key roles in anti-tumor immunity. The percentage of B cells in blood lymphocytes was selectively decreased after the radiation, concomitantly with an increase in that of helper T cell population, favoring Th1 polarization. The IFN-gamma level in splenocyte culture prepared from EST-bearing mice was significantly increased 48 h after the radiation, though the level of

Radio protective effects of calcium channel blockers (Deltiazem) on survival of Saccharomyces cerevisiae cells irradiated with different doses of gamma rays

Energy Technology Data Exchange (ETDEWEB)

Alya, G; Shamma, M; Sharabi, N [Atomic Energy Commission, Damascus (Syrian Arab Republic), Dept. of Molecular Biology and Biotechnology

2007-03-15

Investigations of radioprotective effects of Deltiazem (as one of the commonly used calcium channel blockers, which is used in the treatment of acute and chronic angina and spasmo angina, in addition to the treatment of different types of essential hypertension) has been carried on Saccharomyces Cerevisiae cells. Cells cultures of the most famous yeast Saccharomyces Cerevisiae (bakers yeast) were irradiated with different doses of gamma rays. Results revealed that the necessary dose of gamma rays that leads to 10% of survived cellular population (D10 value) was about 256 Gy. This irradiation dose was used then in all irradiation experiments on culture of S. Cerevisiae cells in which different concentrations of Deltiazem (55, 110, 165 mg/Kg medium) were added before and after irradiation in order to study the radio protective effect of Deltiazem. Results showed that Deltiazem enhances survival percentage of irradiated S. Cerevisiae cultures in a concentration dependent manner. This study confirmed our previous works, which had demonstrated that Deltiazem protects lethally and supralethally irradiated rats, and enhances survival of pre-irradiated Deltiazem treated animals.(author)

Radio protective effects of calcium channel blockers (Deltiazem) on survival of Saccharomyces cerevisiae cells irradiated with different doses of gamma rays

International Nuclear Information System (INIS)

Alya, G.; Shamma, M.; Sharabi, N.

2007-03-01

Investigations of radioprotective effects of Deltiazem (as one of the commonly used calcium channel blockers, which is used in the treatment of acute and chronic angina and spasmo angina, in addition to the treatment of different types of essential hypertension) has been carried on Saccharomyces Cerevisiae cells. Cells cultures of the most famous yeast Saccharomyces Cerevisiae (bakers yeast) were irradiated with different doses of gamma rays. Results revealed that the necessary dose of gamma rays that leads to 10% of survived cellular population (D10 value) was about 256 Gy. This irradiation dose was used then in all irradiation experiments on culture of S. Cerevisiae cells in which different concentrations of Deltiazem (55, 110, 165 mg/Kg medium) were added before and after irradiation in order to study the radio protective effect of Deltiazem. Results showed that Deltiazem enhances survival percentage of irradiated S. Cerevisiae cultures in a concentration dependent manner. This study confirmed our previous works, which had demonstrated that Deltiazem protects lethally and supralethally irradiated rats, and enhances survival of pre-irradiated Deltiazem treated animals.(author)

Cell death induced by gamma irradiation of developing skeletal muscle

International Nuclear Information System (INIS)

Olive, M.; Blanco, R.; Rivera, R.; Cinos, C.; Ferrer, I.

1995-01-01

Newborn Sprague-Dawley rats were exposed to a single dose of 2 Gy gamma rays and killed from 6 h to 5 d later. Increased numbers of dying cells, characterised by their extreme chromatin condensation and often nuclear fragmentation were seen in skeletal muscle 6 h after irradiation. Dying cells decreased to nearly normal values 48 h later. In situ labelling of nuclear DNA fragmentation identified individual cells bearing fragmented DNA. The effects of gamma rays were suppressed following cycloheximide i.p. at a dose of 1 μg/g body weight given at the time of irradiation. Taken together, the present morphological and pharmacological results suggest that gamma ray induced cell death in skeletal muscle is apoptotic, and that the process is associated with protein synthesis. Finally, proliferating cell nuclear antigen-immunoreactive cells, which were abundant in control rats, decreased in number 48 h after irradiation. However, a marked increase significantly above normal age values was observed at the 5th day, thus suggesting that regeneration occurs following irradiation-induced cell death in developing muscle. (author)

Application of gamma irradiation for the enhanced physiological properties of polysaccharides from seaweeds

International Nuclear Information System (INIS)

Choi, Jong-il; Kim, Hyun-Joo; Kim, Jae-Hun; Byun, Myung-Woo; Soo Chun, Byeong; Hyun Ahn, Dong; Hwang, Young-Jeong; Kim, Duk-Jin; Kim, Gwang Hoon; Lee, Ju-Woon

2009-01-01

Polysaccharides from seaweeds, fucoidan and laminarin, were irradiated with gamma rays, and their structural changes and anti-oxidative activities were investigated. The gamma irradiation decreased the average molecular weights of polysaccharides, and UV spectra of irradiated polysaccharides showed increases in the numbers of carboxyl and carbonyl groups and double bonds. DPPH radical scavenging ability and reducing power of the gamma irradiated polysaccharides were significantly higher than those non-irradiated.

Gamma-Ray Irradiation Effects on the Characteristics of New Material P Type 6H-SiC Ni-Schottky Diodes (Application For Nuclear Fuel Facilities)

International Nuclear Information System (INIS)

U-Sudjadi; T-Ohshima, N. Iwamoto; S-Hishiki; N-Iwamoto, K. Kawano

2007-01-01

Effects of gamma-ray irradiation on electrical characteristics of new material p type 6H-SiC Ni-Schottky diodes were investigated. Ni Schottky diodes fabricated on p type 6H-SiC epi-layer were irradiated with gamma-rays at RT. The electrical characteristics of the diodes were evaluated before and after irradiation. The value of the on-resistance does not change up to 1 MGy, and the value increases with increasing absorbed dose above 1 MGy. For n factor, no significant increase is observed below 500 kGy, however, the value increases above 500 kGy. Schottky Barrier Height (SBH) decreases with increasing absorbed dose. Leakage current tends to increase due to irradiation. (author)

Opto-structural characterization of gamma irradiated Bayfol polymer track detector

Energy Technology Data Exchange (ETDEWEB)

Tayel, A. [Physics Department, Faculty of Industrial Education, Helwan University, Cairo (Egypt); Zaki, M.F., E-mail: moha1016@yahoo.com [Experimental Nuclear Physics Department, Nuclear Research Center, Atomic Energy Authority, P.O. 13759, Abu Zaabal, Cairo (Egypt); El Basaty, A.B. [Physics Department, Faculty of Industrial Education, Helwan University, Cairo (Egypt); Hegazy, Tarek M. [Physics Department, College of Women for Arts, Science and Education, Ain Shams University, Cairo (Egypt)

2013-11-15

Bayfol CR 1-4 is one of polymeric solid state nuclear track detector which has numerous applications due to its outstanding optical, mechanical, thermal and electrical properties. In the present study, Bayfol polymer is irradiated with different doses of gamma rays ranging from 0 to 1000 KGy. The effects of gamma irradiations on the optical, structural and chemical properties of Bayfol were studied using Ultraviolet and visible (UV/Vis) spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The UV–Vis spectra of irradiated samples show that the absorption edge is shifted towards longer wavelength comparing to pristine sample spectrum. This behavior indicates that there is a decrease in the band gap after irradiation. The maximum decrease in the band gap is about 0.8 eV. The XRD patterns of amorphous halo of pristine and irradiated samples show a fluctuation of integrated intensity of amorphous halo. This indicates a change in the structure due to gamma irradiation. In order to understand that structure change mechanism, we used the FTIR spectroscopy.

Morphological investigations on the tulip plants irradiated by gamma rays, 1

International Nuclear Information System (INIS)

Matsubara, Hisao

1975-01-01

The present investigation was carried out in order to find out the effects of irradiation on the flower organ formation in tulip and to elucidate the mechanisms of the morphological changes anatomically. The bulbs and plants of tulips at the various growing stages, from the early stage of the flower bud differentiation (July) to the late stage of appearance of flower bud (March) were irradiated with cobalt-60 gamma rays. Dosages employed were 0.5, 1 and 3 krad at dose rates of 1.6 x 10 2 and 1.4 x 10 4 rad/hr. The results of the observation are as follows: 1. The remarkable retardations in the development of flower organs were observed by the irradiation at the stages during and immediately after the flower bud differentiation, whereas the retardations were slight at the stages of flower bud formation after the completion of the differentiation. 2. The dwarfish plants with abnormal flower were obtained after the high dose irradiation at the early stages of the differentiation, whereas the dwarfish plants with narrow petals were obtained by the irradiation at the stages after the completion of flower bud differentiation. 3. The flower with the petals deformed or breaked was obtained by the high dose irradiation at the stages during flower bud differentiation. 4. The feature in color change of a flower was also varied with the different stages irradiated, etc. (JPN)

Crosslinking of electrospun poly (VDF-co-HFP) nanofibrous membranes by gamma-ray irradiation

International Nuclear Information System (INIS)

Kim, Yun Hye; Lim, Youn Mook; Choi, Jae Hak; An, Sung Jun; Park, Jong Seok; Nho, Young Chang

2008-01-01

Poly (VDF-co-HFP)/PEGDMA nanofibrous membranes (NFMs) have been prepared by an electrospinning process. Since electrospun NFMs have a nanoporous structure, they have a potential application for a polymer electrolyte or a separator. Poly (VDF-co-HFP) is a polymer electrolyte binder. In order to improve their mechanical properties, poly (VDF-co-HFP)/PEGDMA NFMs were crosslinked by a gamma-ray irradiation. Then the crosslinked NFMs were characterized through an electrolyte uptake, IR structural analysis, and SEM morphological investigation

Effect of gamma irradiation on Korean traditional multicolored paintwork

International Nuclear Information System (INIS)

Yoon, Minchul; Kim, Dae-Woon; Choi, Jong-il; Chung, Yong-Jae; Kang, Dai-Ill; Hoon Kim, Gwang; Son, Kwang-Tae; Park, Hae-Jun; Lee, Ju-Woon

2015-01-01

Gamma irradiation can destroy fungi and insects involved in the bio-deterioration of organic cultural heritages. However, this irradiation procedure can alter optical and structural properties of historical pigments used in wooden cultural heritage paintings. The crystal structure and color centers of these paintings must be maintained after application of the irradiation procedure. In this study, we investigated the effects of gamma irradiation on Korean traditional multicolored paintwork (Dancheong) for the preservation of wooden cultural heritages. The main pigments in Korean traditional wooden cultural heritages, Sukganju (Hematite; Fe 2 O 3 ), Jangdan (Minium; Pb 3 O 4 ), Whangyun (Crocoite; PbCrO 4 ), and Jidang (Rutile; TiO 2 ), were irradiated by gamma radiation at doses of 1, 5, and 20 kGy. After irradiation, changes in Commision Internationale d’Eclairage (CIE) color values (L*, a*, b*) were measured using the color difference meter, and their structural changes were analyzed using X-ray diffraction (XRD) analysis. The slightly change in less than 1 dE* unit by gamma irradiation was observed, and structural changes in the Dancheong were stable after exposure to 20 kGy gamma irradiation. In addition, gamma irradiation could be applied to painted wooden cultural properties from the Korean Temple. Based on the color values, gamma irradiation of 20 kGy did not affect the Dancheong and stability was maintained for five months. In addition, the fungicidal and insecticidal effect by less than 5 kGy gamma irradiation was conformed. Therefore, the optical and structural properties of Dancheong were maintained after gamma irradiation, which suggested that gamma irradiation can be used for the preservation of wooden cultural heritages painted with Dancheong. - Highlights: • Effects of gamma irradiation on the Dancheong were evaluated. • We confirmed that optical and structural properties of Dancheong were maintained. • Irradiation can contribute the

The resistance changes of carbon and metal oxide film resistors by irradiation of 60Co γ rays

International Nuclear Information System (INIS)

Okamoto, Shinichi; Fujino, Takahiro; Furuta, Junichiro; Yoshida, Toshio

1979-01-01

The resistance changes of glass-sealed deposited-carbon-film and carbon-coated-film resitors and metal oxide glazed resistors made in USA were studied by gamma-ray irradiation. (1) The resistances of deposited-carbon-film resistors of 50, 100 and 200 megohm did not change by irradiation of gamma rays up to 1.9 x 10 9 R. (2) The carbon-coated-film resistors of 100, 1000, 10000 and 100000 megohm had negative resistance changes by irradiation of gamma rays up to 9.9 x 10 8 R. (3) The resistances of metal oxide glazed resistors of 100, 1000 and 10000 megohm did not change by irradiation of gamma rays up to 8.8 x 10 8 R. When radiation monitoring instruments with hi-meg resistors are used in a gamma field with high intensity, the resistors must not be exposed to gamma rays with high doses, or the resistors which do not change by gamma-ray irradiation must be selected. (author)

Developmental toxicity and oxidative stress induced by gamma irradiation in zebrafish embryos.

Science.gov (United States)

Hu, Miao; Hu, Nan; Ding, Dexin; Zhao, Weichao; Feng, Yongfu; Zhang, Hui; Li, Guangyue; Wang, Yongdong

2016-11-01

This study aimed to evaluate the biological effects of gamma irradiation on zebrafish embryos. Different doses of gamma rays (0.01, 0.05, 0.1, 0.5 and 1 Gy) were used to irradiate zebrafish embryos at three developmental stages (stage 1, 6 h post-fertilization (hpf); stage 2, 12 hpf; stage three, 24 hpf), respectively. The survival, malformation and hatching rates of the zebrafish embryos were measured at the morphological endpoint of 96 hpf. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-transferase (GST) were assayed. Morphology analysis showed that gamma irradiation inhibited hatching and induced developmental toxicity in a dose-dependent manner. Interestingly, after irradiation the malformation rate changed not only in a dose-dependent manner but also in a developmental stage-dependent manner, indicating that the zebrafish embryos at stage 1 were more sensitive to gamma rays than those at other stages. Biochemical analysis showed that gamma irradiation modulated the activities of antioxidant enzymes in a dose-dependent manner. A linear relationship was found between GPx activity and irradiation dose in 0.1-1 Gy group, and GPx was a suitable biomarker for gamma irradiation in the dose range from 0.1 to 1 Gy. Furthermore, the activities of SOD, CAT, GR and GPx of the zebrafish embryos at stage 3 were found to be much higher than those at other stages, indicating that the zebrafish embryos at stage 3 had a greater ability to protect against gamma rays than those at other stages, and thus the activities of antioxidant enzymes changed in a developmental stage-dependent manner.

Developmental toxicity and oxidative stress induced by gamma irradiation in zebrafish embryos

International Nuclear Information System (INIS)

Hu, Miao; Hu, Nan; Ding, Dexin; Zhao, Weichao; Feng, Yongfu; Zhang, Hui; Li, Guangyue; Wang, Yongdong

2016-01-01

This study aimed to evaluate the biological effects of gamma irradiation on zebrafish embryos. Different doses of gamma rays (0.01, 0.05, 0.1, 0.5 and 1 Gy) were used to irradiate zebrafish embryos at three developmental stages (stage 1, 6 h post-fertilization (hpf); stage 2, 12 hpf; stage three, 24 hpf), respectively. The survival, malformation and hatching rates of the zebrafish embryos were measured at the morphological endpoint of 96 hpf. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-transferase (GST) were assayed. Morphology analysis showed that gamma irradiation inhibited hatching and induced developmental toxicity in a dose-dependent manner. Interestingly, after irradiation the malformation rate changed not only in a dose-dependent manner but also in a developmental stage-dependent manner, indicating that the zebrafish embryos at stage 1 were more sensitive to gamma rays than those at other stages. Biochemical analysis showed that gamma irradiation modulated the activities of antioxidant enzymes in a dose-dependent manner. A linear relationship was found between GPx activity and irradiation dose in 0.1-1 Gy group, and GPx was a suitable biomarker for gamma irradiation in the dose range from 0.1 to 1 Gy. Furthermore, the activities of SOD, CAT, GR and GPx of the zebrafish embryos at stage 3 were found to be much higher than those at other stages, indicating that the zebrafish embryos at stage 3 had a greater ability to protect against gamma rays than those at other stages, and thus the activities of antioxidant enzymes changed in a developmental stage-dependent manner. (orig.)

Developmental toxicity and oxidative stress induced by gamma irradiation in zebrafish embryos

Energy Technology Data Exchange (ETDEWEB)

Hu, Miao; Hu, Nan; Ding, Dexin; Zhao, Weichao; Feng, Yongfu; Zhang, Hui; Li, Guangyue; Wang, Yongdong [University of South China, Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, Hengyang, Hunan Province (China)

2016-11-15

This study aimed to evaluate the biological effects of gamma irradiation on zebrafish embryos. Different doses of gamma rays (0.01, 0.05, 0.1, 0.5 and 1 Gy) were used to irradiate zebrafish embryos at three developmental stages (stage 1, 6 h post-fertilization (hpf); stage 2, 12 hpf; stage three, 24 hpf), respectively. The survival, malformation and hatching rates of the zebrafish embryos were measured at the morphological endpoint of 96 hpf. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-transferase (GST) were assayed. Morphology analysis showed that gamma irradiation inhibited hatching and induced developmental toxicity in a dose-dependent manner. Interestingly, after irradiation the malformation rate changed not only in a dose-dependent manner but also in a developmental stage-dependent manner, indicating that the zebrafish embryos at stage 1 were more sensitive to gamma rays than those at other stages. Biochemical analysis showed that gamma irradiation modulated the activities of antioxidant enzymes in a dose-dependent manner. A linear relationship was found between GPx activity and irradiation dose in 0.1-1 Gy group, and GPx was a suitable biomarker for gamma irradiation in the dose range from 0.1 to 1 Gy. Furthermore, the activities of SOD, CAT, GR and GPx of the zebrafish embryos at stage 3 were found to be much higher than those at other stages, indicating that the zebrafish embryos at stage 3 had a greater ability to protect against gamma rays than those at other stages, and thus the activities of antioxidant enzymes changed in a developmental stage-dependent manner. (orig.)

Gamma-ray spectrometric measurements of fission rate ratios between fresh and burnt fuel following irradiation in a zero-power reactor

Energy Technology Data Exchange (ETDEWEB)

Kröhnert, H., E-mail: hanna.kroehnert@ensi.ch [Paul Scherrer Institut (PSI), CH-5232 Villigen (Switzerland); École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Perret, G.; Murphy, M.F. [Paul Scherrer Institut (PSI), CH-5232 Villigen (Switzerland); Chawla, R. [Paul Scherrer Institut (PSI), CH-5232 Villigen (Switzerland); École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

2013-01-11

The gamma-ray activity from short-lived fission products has been measured in fresh and burnt UO{sub 2} fuel samples after irradiation in a zero-power reactor. For the first time, short-lived gamma-ray activity from fresh and burnt fuel has been compared and fresh-to-burnt fuel fission rate ratios have been derived. For the measurements, well characterized fresh and burnt fuel samples, with burn-ups up to 46 GWd/t, were irradiated in the zero-power research reactor PROTEUS. Fission rate ratios were derived based on the counting of high-energy gamma-rays above 2200 keV, in order to discriminate against the high intrinsic activity of the burnt fuel. This paper presents the measured fresh-to-burnt fuel fission rate ratios based on the {sup 142}La (2542 keV), {sup 89}Rb (2570 keV), {sup 138}Cs (2640 keV) and {sup 95}Y (3576 keV) high-energy gamma-ray lines. Comparisons are made with the results of Monte Carlo modeling of the experimental configuration, carried out using the MCNPX code. The measured fission rate ratios have 1σ uncertainties of 1.7–3.4%. The comparisons with calculated predictions show an agreement within 1–3σ, although there appears to be a slight bias (∼3%).

Gamma spectrometrical examination of irradiated fuel

International Nuclear Information System (INIS)

Kristof, Edvard; Pregl, Gvido

1988-01-01

Gamma scanning is the only non-destructive technique for quantitative measuring of fission or activation products in spent fuel. The negligence of local variation of the linear attenuation coefficient of gamma rays in the irradiated fuel remains the main source of systematic error. To eliminate it we combine the (single) emission gamma ray scanning technique with a transmission measurement. Mathematical procedure joined with the experiment is particularly convenient for fuel elements of circular cross-section. In such a manner good results are obtainable even for relatively small number of measuring data. Accomplished routines enable to esteem the finite width of the collimation slit. The experiment has been partially automated. Trial measurements were carried out, and the measured data were successfully processed

Environmental studies on X- and {gamma}-irradiated LiCsSO{sub 4} crystals

Energy Technology Data Exchange (ETDEWEB)

Kassem, M.E

2003-09-01

Thermoluminescence (TL) characteristics of LiCsSO{sub 4} crystal have been studied after exposure to different doses of X and {gamma} radiations. The glow curves showed TL response of three peaks at 75 deg. C, 125 deg. C and 250 deg. C. The structure of the glow peaks due to X-rays is quite different from that due to {gamma}-rays. UV exposure yields a regeneration of the TL peaks for the post-irradiated samples with X- or {gamma}-radiation with some changes in the peak structure especially the third peak. For the post-X-ray irradiated crystals, the area under the third glow peak (PK III) increased linearly with the integrated time of UV exposure till about 30 min after which no changes were observed; while, for the post-{gamma}-irradiated crystals, two linear regions were observed. The models of the TL response for the post-irradiated samples as a result of exposure to UV are discussed.

Gamma irradiation of cholestenone oximes

International Nuclear Information System (INIS)

Uenseren, Envare.

1976-01-01

Irradiation of cholest-4-en-3-one and cholest-5-en-3-one oximes with cobalt-60 gamma-rays in different solvents at different doses gave a mixture of products from which ketones corresponding to the starting oximes, Beckmann type rearrangement products, and some other radiolysis products have been isolated and identified

Effects of gamma irradiation for quality of marine products

International Nuclear Information System (INIS)

Yamashita, Michiaki; Ishida, Noriko

2004-01-01

Muscles of sardine and tuna were used as an experimental materials for research of relations between radiation dose and lipid deterioration, lipid hydroperoxide and fish protein. The experimental samples were irradiated by 60 Co source within 0.1∼2 kGy of gamma-ray doses. Methylene blue inducer was used for quantification of the lipid hydroperoxide which was generated in the irradiated samples. High sensitive and quantitative micro-analysis for the lipid hydroperoxide which were produced singularly by gamma-ray irradiation was established on marine products. The lipid hydroperoxide in marine products was generated by oxidation of unsaturated fatty acid. Reaction mechanism of the lipid hydroperoxide which modified a protein of muscle fiber in particular was estimated. (M. Suetake)

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

International Nuclear Information System (INIS)

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

2008-01-01

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

The measurement of gamma ray induced heating in a mixed neutron and gamma ray environment

International Nuclear Information System (INIS)

Chiu, H.K.

1991-10-01

The problem of measuring the gamma heating in a mixed DT neutron and gamma ray environment was explored. A new detector technique was developed to make this measurement. Gamma heating measurements were made in a low-Z assembly irradiated with 14-Mev neutrons and (n, n') gammas produced by a Texas Nuclear Model 9400 neutron generator. Heating measurements were made in the mid-line of the lattice using a proportional counter operating in the Continuously-varied Bias-voltage Acquisition mode. The neutron-induced signal was separated from the gamma-induced signal by exploiting the signal rise-time differences inherent to radiations of different linear energy transfer coefficient, which are observable in a proportional counter. The operating limits of this measurement technique were explored by varying the counter position in the low-Z lattice, hence changing the irradiation spectrum observed. The experiment was modelled numerically to help interpret the measured results. The transport of neutrons and gamma rays in the assembly was modelled using the one- dimensional radiation transport code ANISN/PC. The cross-section set used for these calculations was derived from the ENDF/B-V library using the code MC 2 -2 for the case of DT neutrons slowing down in a low-Z material. The calculated neutron and gamma spectra in the slab and the relevant mass-stopping powers were used to construct weighting factors which relate the energy deposition in the counter fill-gas to that in the counter wall and in the surrounding material. The gamma energy deposition at various positions in the lattice is estimated by applying these weighting factors to the measured gamma energy deposition in the counter at those locations

Effects of gamma-rays irradiation in seed of mungbean (vigna radiata (L.) wilczek) composition of media on shoot regeneration of explants from node of cotyledon

International Nuclear Information System (INIS)

Hutabarat, Dameria; H, Soeranto

1998-01-01

Study the effects of gamma-rays irradiation and composition and media on shoot regeneration of explants from node of cotyledon of mungbean. Wallet variety have been conducted. The explants derived of irradiated seeds of 10-20 Gy of gamma rays were planted in the 0.7% agar solution. One day after planting in the agar media the embryo axis of germinate seed were removed and the node of cotyledon were cultured in the regeneration media as examples. The results shown that shoot regeneration was influenced by media composition and the doses of gamma rays irradiation in seed. In the MURASHIGE and SKOOG medium which contain of BAP or 2-iP or Kinetin with 3 ppm concentrate respectively the explants could produced 100% of shoots. However, the highest. number of produced shoot (3 shoots) was showed in the medium which contained of BAP. The medium with I ppm concentrate od BAP could produced 100% shoot regeneration and the maximum number of shoots (4 shoots) per explant was showed in with 5 ppm. concentrate of BAP. The effectivity off BAP for shoot regeneration by enrichment of 12 ppm Ag 2 SO 4 in the media. Irradiation of 10-20 Gy gamma rays on seeds of mungbean walet variety could improved shoot regeneration of explants from node cotyledon. (author)

Detection of irradiated fresh fruits treated by e-beam or gamma rays

International Nuclear Information System (INIS)

Marin-Huachaca, N.S.; Lamy-Freund, Maria Tereza; Mancini-Filho, Jorge; Delincee, Henry; Villavicencio, A.L.C.H.

2002-01-01

Since about 1990, the amount of commercially irradiated food products available worldwide has increased. Commercial irradiation of foods has been allowed in Brazil since 1973 and now more than 20 different food products are approved. Among these products are a number of fresh fruits which may be irradiated for insect disinfestation, to delay ripening and to extend shelf-life. Today, there is a growing interest to apply radiation for the treatment of fruits instead of using fumigation or e.g. vapour-heat treatments, and an increased international trade in irradiated fruits is expected. To ensure free consumer choice, methods to identify irradiated foods are highly desirable. In this work, three detection methods for irradiated fruits have been employed: DNA Comet Assay, the half-embryo test and ESR. Both electron-beam (e-beam) and gamma rays were applied in order to compare the response with these two different kinds of radiation. Fresh fruits such as oranges, lemons, apples, watermelons and tomatoes were irradiated with doses in the range 0, 0.50, 0.75, 1.0, 2.0 and 4.0 kGy. For analysis, the seeds of the fruits were utilized. Both DNA Comet Assay and the half-embryo test enabled an easy identification of the radiation treatment. However, under our conditions, ESR measurements were not satisfactory

Gamma irradiation-induced variation in carrots (Daucus carota L.)

International Nuclear Information System (INIS)

Al-Safadi, B.; Simon, P.W.

1996-01-01

Carrot tissue cultures, germinating seed, and dry seed were exposed to gamma radiation. Irradiation accelerated germination of carrot seed in the M1 generation at low doses (0.5 and 1 krad), whereas higher doses delayed germination. A high negative correlation was observed between dose and survival of plants after seed irradiation. Plant size and root weight were 20% to 35% greater than control plants after seeds, but not tissue cultures, were exposed to low doses of gamma irradiation. Higher doses reduced M1 plant size by 50% in germinating seed and tissue culture treatments but less for the dry seed treatment. Seed production decreased while phenotypic variation of M1 plants increased with increasing gamma ray dosage. Root weight and total dissolved solids were highly variable in M2 families. Less variation was observed in total carotene content and none was seen in sugar type (reducing vs. non reducing sugars). Induced variation in root color and root shape was also observed. Irradiation of germinating seed and tissue cultures yielded more M2 variation than irradiation of dry seed. Putative point mutations were not observed. Unirradiated carrot tissue cultures did not yield significant M2 somaclonal variation. Average root weight of M2 plants increased with increasing gamma ray dosage, especially for the dry seed treatment

Gamma irradiation induced variation in carrots (Daucus Carota L.)

International Nuclear Information System (INIS)

Al-Safady, B.; Simon, P.W.

1999-01-01

Carrot tissue cultures, germinating seed, and dry seed were exposed to gamma radiation. Irradiation accelerated germination of carrot seed in the M 1 generation at low doses (0.5 and 1 krad), whereas higher doses delayed germination. A high negative correlation was observed between dose and survival of plants after seed irradiation. Plant size and root weight were 20% to 35% greater than control plants after seeds, but not tissue culture, were exposed to low doses of gamma irradiation. Higher doses reduced M 1 plant size by > 50% in germinating seed and tissue culture treatments but less for the dry seed treatment. Seed production decreased while phenotypic variation of M 1 plants increased with increasing gamma ray dosage. Root weight and total dissolved solids were highly variable in M 2 families. Less variation was observed in total carotene content and none was seen in sugar type [reducing vs. non reducing sugars]. Induced variation in root color and rot shape was also observed. Irradiation of germinating seed and tissue cultures yielded more M 2 variation than irradiation of dry seed. Putative point mutations were not observed. Unirradiated carrot tissue cultures did not yield significant M 2 somaclonal variation. Average root weight of M 2 plants increased with increasing gamma ray dosage, especially for the dry seed treatment (Author)

Effect of gamma irradiation on essential oils and lipids in spices

International Nuclear Information System (INIS)

Kaneko, Nobutada; Ito, Hitoshi; Ishigaki, Isao

1991-01-01

Four kinds of spices were irradiated with gamma-rays at a dose of 10 to 50 kGy. Studies on radiation effect on essential oils and lipids in spices were carried out by gas-chromatography (GC). The GC analysis of lipids in spices revealed that components were not changed even after irradiation up to 50 kGy of gamma-rays. Radiation effect on components of essential oils in spices were analyzed by headspace-GC (HS-GC) and GC after separation to hydrocarbon compounds and oxygen compounds, and any degradation of components was not observed up to 50 kGy of irradiation. On the contrary, essential oils of cloves sterilized by heat treatment were apparently decreased as compared with irradiated and non-irradiated cloves. (author)

Nanodefect formation in LiF crystals under gamma irradiation

International Nuclear Information System (INIS)

Mussaeva, M.A.; Ibragimova, Eh.M.; Kalanov, M.U.; Muminov, M.I.

2006-01-01

One studied the spectra of absorption and of photoluminescence, microhardness and performed X-ray structure analysis of gamma-irradiated LiF crystals in a shutdown reactor and in 60 Co source when gamma-radiation dose rate was equal to 7.65 Gy/s. In addition to formation of point and combined radiation defects one detected the presence of the gamma-irradiation induced 28 nm size nanoparticles of LiOH phase in Li sublattice. Formation of defects is shown to occur more efficiently in a shutdown reactor in contrast to 60 Co source [ru

Effect of gamma irradiation in sterilization of dry dextran as plasma substitute and sodium chloride

Energy Technology Data Exchange (ETDEWEB)

Piatkiewicz, A; Kusewicz, D [Politechnika Lodzka (Poland)

1975-01-01

The exposure of dry dextran, sodium chloride and polyethylene packing to 0,3-2 Mrad of gamma irradiation decreased their contamination by 60 to 96%. The sterilization effect of irradiation increased with gamma-ray dose. Spores of Bacillus subtilis and Aspergillus niger were shown to be the most resistant to gamma-ray treatment. In some samples the resistant Micrococcus was also detected.

Effects of gamma irradiations on reactive pulsed laser deposited vanadium dioxide thin films

Science.gov (United States)

Madiba, I. G.; Émond, N.; Chaker, M.; Thema, F. T.; Tadadjeu, S. I.; Muller, U.; Zolliker, P.; Braun, A.; Kotsedi, L.; Maaza, M.

2017-07-01

Vanadium oxide films are considered suitable coatings for various applications such as thermal protective coating of small spacecrafts because of their thermochromic properties. While in outer space, such coating will be exposed to cosmic radiations which include γ-rays. To study the effect of these γ-rays on the coating properties, we have deposited vanadium dioxide (VO2) films on silicon substrates and subjected them to extensive γ-irradiations with typical doses encountered in space missions. The prevalent crystallographic phase after irradiation remains the monoclinic VO2 phase but the films preferential orientation shifts to lower angles due to the presence of disordered regions caused by radiations. Raman spectroscopy measurements also evidences that the VO2 structure is slightly affected by gamma irradiation. Indeed, increasing the gamma rays dose locally alters the crystalline and electronic structures of the films by modifying the V-V inter-dimer distance, which in turns favours the presence of the VO2 metallic phase. From the XPS measurements of V2p and O1s core level spectra, an oxidation of vanadium from V4+ towards V5+ is revealed. The data also reveal a hydroxylation upon irradiation which is corroborated by the vanishing of a low oxidation state peak near the Fermi energy in the valence band. Our observations suggest that gamma radiations induce the formation of Frenkel pairs. Moreover, THz transmission measurements show that the long range structure of VO2 remains intact after irradiation whilst the electrical measurements evidence that the coating resistivity decreases with gamma irradiation and that their transition temperature is slightly reduced for high gamma ray doses. Even though gamma rays are only one of the sources of radiations that are encountered in space environment, these results are very promising with regards to the potential of integration of such VO2 films as a protective coating for spacecrafts.

On enzyme kinetic parameters modification of gamma irradiation

International Nuclear Information System (INIS)

Ferdes, O.S.; Ferdes, M.; Turcu, G.R.

1993-01-01

To elucidate the molecular mechanisms of gamma-ray action on biomolecules there were investigated the modifications in activity and other kinetic parameters for some enzymes irradiated in pure dry state at relative high doses. There were considered bacterial and fungal α-amylases, glucoamylase and Mucor sp. protease irradiated by a 60 Co gamma-ray source in the dose range 1.0-30.0 kGy, at different dose-rates between 0.5-2.0 kGy/h, at room temperature. Considering the enzyme inactivation in this dose range, the dose-effect relationships have an expected form and depend on the irradiation conditions but not significantly on the dose rate. The catalytic properties of enzymes were modified by irradiation. By usual methods it is evidenced a direct correlation between the enzymatic activities, Michaelis-Menten constant, K m , reaction velocities, v, and the irradiation dose. These experimental findings can support a self-consistent theoretical approach on biophysical radiation action on biological active molecules like enzymes. At the same time, some enzyme behaviour to irradiation could be considered like a good biological indicator of radiation response. (Author) 4 Figs., 19 Refs

Effect of Gamma Rays on Some Biological performance of Chrysomya bezziana(VILL.)

International Nuclear Information System (INIS)

Al Seria, M. H.; Al Taweel, A.A.; Ahmed, A.M.; Al Izzi, M.A.J.

2006-01-01

The effect of different does of gamma rays on some biological performance of Old World Screwworm fly (OWSWF), Chrysomya bezziana exposed as pupae at different ages were investigated. Results reveealed that the ages of produced adults were effected significantly as the dose of gamma rays increased and the ages of irradiated pupae decreased While no effect was observed in sex ratio of emerged adults at any ages of irradiated pupae. The results have also showed that the female fecundity and percent of egg hatch were significantly effected as the dose of gamma ray increased for both type of mating investigated.

Enhanced micronucleus formation in the descendants of {gamma}-ray-irradiated tobacco cells: Evidence for radiation-induced genomic instability in plant cells

Energy Technology Data Exchange (ETDEWEB)

Yokota, Yuichiro, E-mail: yokota.yuichiro@jaea.go.jp [Life Science and Biotechnology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan); Funayama, Tomoo; Hase, Yoshihiro [Life Science and Biotechnology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan); Hamada, Nobuyuki [Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry, 2-11-1 Iwado-kita, Komae, Tokyo 201-8511 (Japan); Kobayashi, Yasuhiko; Tanaka, Atsushi; Narumi, Issay [Life Science and Biotechnology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan)

2010-09-10

Ionizing radiation-induced genomic instability has been documented in various end points such as chromosomal aberrations and mutations, which arises in the descendants of irradiated mammalian or yeast cells many generations after the initial insult. This study aimed at addressing radiation-induced genomic instability in higher plant tobacco cells. We thus investigated micronucleus (MN) formation and cell proliferation in tobacco cells irradiated with {gamma}-rays and their descendants. In {gamma}-irradiated cells, cell cycle was arrested at G{sub 2}/M phase at around 24 h post-irradiation but released afterward. In contrast, MN frequency peaked at 48 h post-irradiation. Almost half of 40 Gy-irradiated cells had MN at 48 h post-irradiation, but proliferated as actively as sham-irradiated cells up to 120 h post-irradiation. Moreover, the descendants that have undergone at least 22 generations after irradiation still showed a two-fold MN frequency compared to sham-irradiated cells. This is the direct evidence for radiation-induced genomic instability in tobacco cells.

TL detectors for gamma-ray dose measurements in critically accidents

International Nuclear Information System (INIS)

Miljanic, S.; Knezevic, Z.; Zorko, B.; Gregori, B.

2005-01-01

Full text: Determination of gamma-ray dose in mixed neutron + gamma-ray fields is still a challenging task. Dosemeters used for gamma-ray dosimetry are usually in some extent sensitive to neutrons and their response variations depend on neutron energy i.e. on neutron spectra. Besides, it is necessary to take into account the energy dependence of dosimeter responses to gamma-rays. To reduce all these influences, design of dosemeter holders is of special importance. In this work, several types of thermoluminescent detectors (TLD) placed in different holders used for gamma-ray dose determination in mixed fields were examined. Dosemeters were from three different institutions: Ruder Boscovic Institute (RBI), Croatia, Jozef Stefan Institute (JSI), Slovenia and Autoridad Regulatoria Nuclear (ARN), Argentina. All dosemeters were irradiated during the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, June 2002. At that exercise three accidental scenarios were reproduced: bare reactor, free evolution; lead shielded reactor, steady state; and lead shielded reactor, free evolution. In each irradiation dosemeters were exposed placed on the front of phantom and 'free-in-air'. Also, dosemeters were irradiated in a pure gamma ray field of 60 Co source. Following types of TLDs were used: 7 LiF (TLD-700), CaF 2 :Mn and AI 2 O 3 :Mg,Y - all from RBI; CaF 2 :Mn from JSI and 7 LiF (TLD-700) from ARN. Reported doses were compared with the reference values as well as with the mean participants' values. The results show satisfactory agreement with other dosimetry systems used in the Intercomparison. The influence of different types of holders and applied corrections of dosemeters' readings are discussed. (author)

A deep-level transient spectroscopy study of gamma-ray irradiation on the passivation properties of silicon nitride layer on silicon

Science.gov (United States)

Dong, Peng; Yu, Xuegong; Ma, Yao; Xie, Meng; Li, Yun; Huang, Chunlai; Li, Mo; Dai, Gang; Zhang, Jian

2017-08-01

Plasma-enhanced chemical vapor deposited silicon nitride (SiNx) films are extensively used as passivation material in the solar cell industry. Such SiNx passivation layers are the most sensitive part to gamma-ray irradiation in solar cells. In this work, deep-level transient spectroscopy has been applied to analyse the influence of gamma-ray irradiation on the passivation properties of SiNx layer on silicon. It is shown that the effective carrier lifetime decreases with the irradiation dose. At the same time, the interface state density is significantly increased after irradiation, and its energy distribution is broadened and shifts deeper with respect to the conduction band edge, which makes the interface states becoming more efficient recombination centers for carriers. Besides, C-V characteristics show a progressive negative shift with increasing dose, indicating the generation of effective positive charges in SiNx films. Such positive charges are beneficial for shielding holes from the n-type silicon substrates, i. e. the field-effect passivation. However, based on the reduced carrier lifetime after irradiation, it can be inferred that the irradiation induced interface defects play a dominant role over the trapped positive charges, and therefore lead to the degradation of passivation properties of SiNx on silicon.

Very high-energy gamma rays from gamma-ray bursts.

Science.gov (United States)

Chadwick, Paula M

2007-05-15

Very high-energy (VHE) gamma-ray astronomy has undergone a transformation in the last few years, with telescopes of unprecedented sensitivity having greatly expanded the source catalogue. Such progress makes the detection of a gamma-ray burst at the highest energies much more likely than previously. This paper describes the facilities currently operating and their chances for detecting gamma-ray bursts, and reviews predictions for VHE gamma-ray emission from gamma-ray bursts. Results to date are summarized.

Enhancement of electrical conductivity in gamma irradiated cobalt ferrite nanoparticles

International Nuclear Information System (INIS)

Nawpute, Asha A.; Raut, A.V.; Babrekar, M.K.; Kale, C.M.; Jadhav, K.M.; Shinde, A.B.

2014-01-01

The cobalt ferrite nanoparticles were synthesized by sol-gel auto- combustion method, in which L-ascorbic acid was used as a fuel. The effect of gamma irradiation on the electrical resistivity of cobalt ferrite nanoparticles has been studied. The ferrite powder annealed at 550℃ was irradiated by gamma source 137 Cs. The synthesized nanoparticles were characterized by X-ray diffraction and DC resistivity. (author)

Comparison of gamma ray and electron beam irradiation on extraction yield, morphological and antioxidant properties of polysaccharides from tamarind seed

Energy Technology Data Exchange (ETDEWEB)

Choi, Jong-il [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kim, Jae-Kyung [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Graduate school of Food and Biotechnology, Korea University, Seoul 146-701 (Korea, Republic of); Srinivasan, Periasamy; Kim, Jae-Hun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Park, Hyun-Jin [Graduate school of Food and Biotechnology, Korea University, Seoul 146-701 (Korea, Republic of); Byun, Myung-Woo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

2009-07-15

Tamarind (Tamarindus indica L) seed polysaccharide (TSP) is of great important due to its various biological activities. The present investigation was carried out to compare extraction yield, morphological characteristics, average molecular weights and antioxidant activities of TSP from gamma- and electron beam (EB)-irradiated tamarind kernel powder. The tamarind kernel powder was irradiated with 0, 5 and 10 kGy by gamma ray (GR) and electron beam, respectively. The extraction yield of TSP was increased significantly by EB and GR irradiation, but there was no significant difference between irradiation types. Morphological studies by scanning electron microscope showed that TSP from GR-irradiated tamarind seed had a fibrous structure, different from that of EB irradiated with a particle structures. The average molecular weight of TSP was decreased by the irradiation, and EB treatment degraded more severely than GR. Superoxide radical scavenging ability and total antioxidant capacity of EB-treated TSP showed higher than those of GR-treated TSP.

Evaluation of induced radioactivity in 10 MeV-electron irradiated spices, (1); [gamma]-ray measurement

Energy Technology Data Exchange (ETDEWEB)

Furuta, Masakazu; Katayama, Tadashi; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Shibata, Setsuko; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

1994-02-01

Black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electrons from a linear accelerator to a dose of 100 kGy and radioactivity was measured in order to estimate induced radioactivity in the irradiated foods. Induced radioactivity could not be detected significantly by [gamma]-ray spectrometry in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list of photonuclear reactions which could produce radioactivity below 10 MeV. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (author).

Studies of soy sauce sterilization and its special flavour improvement by gamma-ray irradiation

Science.gov (United States)

Jingtian, Yang; Xinhua, Jin; Guoxing, Gu; Guichun, Yun

Experimental studies for sterilizing 12 kinds of soy sauce with gamma-ray irradiation showed that both of effects for sterilization and improving flavour and quality of soy sauce were obtained simultaneously. All colibacillus in soy sauce were sterilized using 1 kGy radiation dose and total bacteria count in soy sauce can be reduced to below national standard at 5 kGy dose ( 5x10 4count/ml ). But above 10 kGy dose is needed to kill all bacteria in soy sauce. The significant changes on chemical components in soy sauce irradiated at 5-7 kGy dose took place: raduceing-sugar increased by 1-10%, total amount of 18 kinds of free amino acid raised between 3.5-28 %, emerging-sweet smell substances which have low boiling point, such as alchols, aldehydes and esters obviously increased. The taste-specialists from some soy sauce factories concluded that flavour and quality of soy sauce irradiated are better than non-irradiated.

The influence of gamma rays irradiation on chlorophyll mutation and genetic variability of agronomic characters in soybean plant

International Nuclear Information System (INIS)

Ratma, Rivaie; Sumargono, A.M. Riyanti

1998-01-01

Seeds of soybean mutant line No. 13/PsJ with 12% moisture content were irradiated by 0,10;0,20;0.30 and 0.40 kGy of gamma rays treatment. Number of irradiated seed for each treatment was 1500 seeds. Irradiated of seeds were planted in the 4m X 5m plot size with 0,20m x 0,40m spacing and two seed each hole and were planted as M-1 plants in the wet season of 1996/1997 at PAIR field experiment in Pasar Jumat, Jakarta. The experiment was designed Randomized Block Design with three replication Plans of M-1 generation were harvested individuality and were planted as known M2 plants in the next generation in dry season of 1997 at PAIR field experiment. Seven days planting the chlorophyll mutation of plants were recorded by Frydenberg method and the genetic variability of plant height, number of fertile pods and nodes were calculated by Singh and Chaudhary formula. Results of the experiment showed that chlorophyll mutation and genetic variability of plant height and number of fertile pods could be improved be 0.10 and 0,20 kGy of gamma rays treatment. (authors)

Carcinostatic effects of platinum nanocolloid combined with gamma irradiation on human esophageal squamous cell carcinoma.

Science.gov (United States)

Li, Qiang; Tanaka, Yoshiharu; Saitoh, Yasukazu; Tanaka, Hiroshi; Miwa, Nobuhiko

2015-04-15

To explore the carcinostatic effects of platinum nanocolloid (Pt-nc) combined with gamma rays on human esophageal squamous cell carcinoma (ESCC). ESCC-derived KYSE-70 cells were treated with various concentrations of Pt-nc and/or gamma irradiation, and subsequently cultured in phenol red free DMEM with 10% FBS for 48 h. The proliferative status of the KYSE-70 cells was evaluated using trypan blue dye exclusion and WST-8 assays. Cellular and nucleic morphological aspects were evaluated using crystal violet and Hoechst 33342 stainings, respectively. Radiosensitivity was quantified by a cell viability assay, and the activated form of caspase-3, a characteristic apoptosis-related protein, was detected by Western blotting. Although single treatment with either Pt-nc or gamma irradiation could slightly inhibit the growth of the KYSE-70 cells, their combination exerted remarkable carcinostatic effects in a manner dependent on either Pt-nc concentrations or gamma ray doses, compared with the effect of each treatment alone (pirradiated with gamma rays, were shown to undergo distinct apoptotic morphological changes. The carcinostatic effect of gamma rays at 7 Gy without Pt-nc was approximately equal to that when 3-Gy irradiation was combined with 100 ppm Pt-nc or that 5-Gy irradiation was combined with 50 ppm Pt-nc. Pt-nc in combination with gamma rays may exert a cooperative effect through platinum- or gamma ray-induced apoptosis resulting in the inhibition of growth of cancer cells, while concurrently enabling the lowering of the radiative dose. Copyright © 2015 Elsevier Inc. All rights reserved.

Flame-resistant kapok fiber manufactured using gamma ray

International Nuclear Information System (INIS)

Chung, Byung Yeoup; Hyeong, Min Ho; An, Byung Chull; Lee, Eun Mi; Lee, Seung Sik; Kim, Jin-Hong; Kim, Jae-Sung; Kim, Tae-Hoon; Cho, Jae-Young

2009-01-01

Owing to homogeneous hollow tube shape and hydrophobicity of kapok fiber, the usages of this fiber are various such as fiberfill in pillows, quilts, non-woven fabric for oil spill cleanup and plastic green house. Even though kapok fiber is able to apply various industrial usages, it has a serious disadvantage which is the extreme sensitivity to spark or flame. Therefore, we try to make flame-resistant kapok fiber using gamma ray. The radiation caused loss of hydrophobic compounds in kapok fiber and no morphological change, especially fine hollow tube shape, was observed. The lignin contents were negligible changed after gamma irradiation. However, the building units of lignin polymer such as coniferyl alcohol, and sinapyl alcohol were significantly changed that is, functional group as a methoxyl group from lignin polymer was cleaved by gamma irradiation. Based on the results of removal of hydrophobic compounds and cleavage of methoxyl group from lignin polymer, kapok fiber can be converted into a flame-resistant fiber by gamma ray treatment.

Gamma ray auto absorption correction evaluation methodology

International Nuclear Information System (INIS)

Gugiu, Daniela; Roth, Csaba; Ghinescu, Alecse

2010-01-01

Neutron activation analysis (NAA) is a well established nuclear technique, suited to investigate the microstructural or elemental composition and can be applied to studies of a large variety of samples. The work with large samples involves, beside the development of large irradiation devices with well know neutron field characteristics, the knowledge of perturbing phenomena and adequate evaluation of correction factors like: neutron self shielding, extended source correction, gamma ray auto absorption. The objective of the works presented in this paper is to validate an appropriate methodology for gamma ray auto absorption correction evaluation for large inhomogeneous samples. For this purpose a benchmark experiment has been defined - a simple gamma ray transmission experiment, easy to be reproduced. The gamma ray attenuation in pottery samples has been measured and computed using MCNP5 code. The results show a good agreement between the computed and measured values, proving that the proposed methodology is able to evaluate the correction factors. (authors)

Effects of gamma irradiation on the performance of Jatropha (Jatropha curcas L.) accessions

Science.gov (United States)

Surahman, M.; Santosa, E.; Agusta, H.; Aisyah, S. I.; Nisya, F. N.

2018-03-01

This study aimed to assess the effects of mutation by using gamma ray on the performance of jatropha plants. The study was conducted at PAIR BATAN. Jatropha seeds obtained from the collection farm of SBRC LPPM IPB and PT Indocement Tunggal Prakarsa Tbk in Gunung Putri, Bogor, were irradiated. The irradiated seeds were grown in Jonggol Trial Farm of IPB. Gamma irradiation was conducted by using a GCM 4000A device. Treatments consisted of irradiation doses, irradiation methods, and accessions. Irradiation doses given were 175, 200, 225 Gy, and no irradiation (control). Irradiation methods consisted of acute, intermittent, and split-dose. Accessions used in this study were Dompu, Medan, Bima, Lombok, ITP II, IP2P, and Thailand. Results of the study were analysed until 5 months after planting showed that gamma ray mutation gave stimulating and inhibiting effects on similar traits. Irradiation dose of 225 Gy was good to be given in acute, intermittent, and split-dose methods. Irradiation effects were found to be significant in jatropha accessions. Effects of irradiation on production will be published soon.

Effect of. gamma. -irradiation on the crystalline structure of silk fibroin and silk sericin

Energy Technology Data Exchange (ETDEWEB)

Tsukada, Masuhiro; Aoki, Akira

1985-02-01

Changes in the crystalline structure of silk sericin and silk fibroin induced by gamma-irradiation in the atmosphere described. The crystalline structure of silk sericin which had been subjected to gamma-irradiation remained unchanged. However the decomposition temperature of the specimen decreased to about 230 deg C, when the total dose of ..gamma.. rays exceeded 4.6 Mrad. The structure of the silk 1 type crystal of silk fibroin in the solid state, with a low degree of molecular orientation, changed into the silk 2 type crystal, when the total dose of ..gamma.. rays exceeded 4.6 Mrad. No changes in the crystalline structure were observed in the solid state of the silk 2 type crystal regardless of gamma-irradiation. The decrease in the decomposition temperature of the specimen was attributed to the decrease in the molecular orientation. However, the molecular conformation of silk fibroin with a randomly coiled structure remained unchanged even after gamma-irradiation.

Transferases activity in blood plasma of chickens hatched from eggs irradiated during incubation by low dose gamma rays

International Nuclear Information System (INIS)

Kraljevic, P.; Vilic, M.; Miljanic, S.; Simpraga, M.

2005-01-01

In our earlier studies chickens hatched from eggs irradiated with 0.15 Gy gamma rays before incubation showed a significantly higher growth than controls during the fattening period (1-42 days). The activity of aspartate-aminotransferase (AST), alanine-aminotransferase (ALT) and plasma glucose in the same chickens were also significantly higher. These results suggested that low-dose gamma-radiation stimulated certain metabolic processes in chickens hatched from eggs irradiated before incubation. The goal of this study was to determine the effects of low-dose ionising radiation on AST and ALT activity in the blood plasma of chickens hatched from eggs irradiated during incubation. The eggs of heavy breeding chickens (Avian, line 34) were exposed to 0.15 Gy of gamma-radiation (6 0C o) on the seventh day of incubation, i.e. at the time when the organogenesis in chickens is completed. The control group of chickens hatched from non-irradiated eggs. All other conditions were the same for both groups. After hatching, blood samples were taken from the wing vein on days 1, 3, 5, 7, 10, 20, 32 and 42. The activity of both enzymes was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. On day 10, AST and ALT activity were significantly higher in the blood plasma of chickens hatched from irradiated eggs, but it significantly dropped for both enzymes on day 20. Our results indicate that exposure of eggs to low-dose gamma-radiation on the seventh day of incubation affects AST and ALT activity in the blood plasma of chickens hatched from irradiated eggs. However, this effect is somewhat different from the effects of egg exposure to low-dose gamma radiation before incubation.(author)

Improvement of physical properties of SnO2 By Gamma Irradiation

International Nuclear Information System (INIS)

Elttayef, A. K.

2012-12-01

In this work, the structural and optical of properties of (Sno 2 ) thin films prepared by chemical spray pyrolysis technique have been studied before and after irradiation by gamma ray. The films were prepared from mixture of Tin chloride hydrate SnCl 2 .2H 2 O with molar concentration of (0.1 M)at substrate temperature (400)o C and thickness (175,300 nm). X-ray diffraction analysis indicated that all the prepared films have polycrystalline structure. The optical properties of the films were determined by studying the visible and near IR spectrum, which include transmittance, absorbance, reflectance, absorption coefficient and energy gap before and after irradiation by gamma ray. It was found that the irradiance caused increasing the value of transmittance and optical energy gap. (Author)

In vivo adenylate cyclase activity in ultraviolet- and gamma-irradiated Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Chatterjee, A; Bhattacharya, A K

1988-06-01

The incorporation of (/sup 14/C)adenine into the cyclic AMP fraction by whole cells of Escherichia coli B/r was taken as a measure of the in vivo adenylate cyclase activity. This activity was significantly inhibited by irradiation of the cells either with /sup 60/Co ..gamma..-rays or with UV light from a germicidal lamp, suggesting inhibition of cyclic AMP synthesis. The incubation of cells after irradiation with lower doses (50-100 Gy) of ..gamma..-rays produced a significant increase of in vivo adenylate cyclase activity, whereas there was no significant change after high doses (150 Gy and above). Dark incubation of cells after irradiation with UV light (54 J m/sup -2/) led to recovery of enzyme activity to the level measured in unirradiated cells. Thus it appears that the catabolite repression of L-arabinose isomerase induced by UV light, as well as ..gamma..-irradiation, is due to reduced cyclic AMP synthesis in irradiated cells.

In vivo adenylate cyclase activity in ultraviolet- and gamma-irradiated Escherichia coli.

Science.gov (United States)

Chatterjee, A; Bhattacharya, A K

1988-06-01

The incorporation of [14C]adenine into the cyclic AMP fraction by whole cells of Escherichia coli B/r was taken as a measure of the in vivo adenylate cyclase activity. This activity was significantly inhibited by irradiation of the cells either with 60Co gamma-rays or with UV light from a germicidal lamp, suggesting inhibition of cyclic AMP synthesis. The incubation of cells after irradiation with lower doses (50-100 Gy) of gamma-rays produced a significant increase of in vivo adenylate cyclase activity, whereas there was no significant change after higher doses (150 Gy and above). Dark incubation of cells after irradiation with UV light (54 J m-2) led to recovery of enzyme activity to the level measured in unirradiated cells. Thus it appears that the catabolite repression of L-arabinose isomerase induced by UV light, as well as gamma-irradiation, is due to reduced cyclic AMP synthesis in irradiated cells.

Kraft cooking of gamma irradiated wood, (1)

International Nuclear Information System (INIS)

Inaba, Masamitsu; Meshitsuka, Gyosuke; Nakano, Junzo

1979-01-01

Studies have been made of kraft cooking of gamma irradiated wood. Beech (Fagus crenata Blume) wood meal suspended in aqueous alkaline alcohol was irradiated up to 1.5 KGy (0.15 Mrad) with gamma rays from a Co-60 source in the presence or absence of oxygen. The irradiated wood meals were washed thoroughly with fresh water, air dried and cooked under the ordinary cooking conditions. The results are summarized as follows: (1) Pre-irradiation in aqueous alkali have negligible effect on kraft cooking. (2) In the case of ethanol addition (50 g/l), pre-irradiation in vacuo shows acceleration of delignification and stabilization of carbohydrates during kraft cooking. Cooked yield gain by pre-irradiation was about 1.2% in all over the range of delignification from 80 to 90%. Aqueous ethanol without alkali also shows positive but smaller effect than that with alkali. (3) Propanol, iso-propanol and butanol show positive but smaller effects than ethanol. However, methanol does not show any positive effect. (4) Irradiation in the presence of oxygen does not show any attractive effect on kraft cooking. (author)

Electron and gamma-ray irradiated NTD Si p-n structures static and dynamic parameters trade-off

International Nuclear Information System (INIS)

Marchenko, I.G.; Zhdanovich, N.E.; Karas', V.I.

2005-01-01

The comparison of different radiation defects types influence on static and dynamic parameters trade-off of power diodes fabricated on neutron-transmutation doped silicon have been fulfilled. Various defects sets were introduced utilizing electron irradiation (E=6 MeV), gamma-ray Co 60 irradiation and electron irradiation and subsequent annealing at temperature 700 degrees centigrade. It is established that optimal trade-of between forward voltage drop and operation speed is achieved in case of electron irradiation and annealing. In this case recombination process is governed by defect with energy level near middle of forbidden gap (E c -0.53 eV). The results obtained indicate on possibility of using these defect recombination properties for speed control in production of power fast high-voltage devices on the base of neutron-transmutation doped silicon. (authors)

gamma-ray spectra measurements for long cooled MOX spent fuels

International Nuclear Information System (INIS)

Murakami, Kiyonobu; Kobayashi, Iwao

1993-09-01

Gamma-ray spectra of spent fuels have important informations in the estimation of burnup rate, concentration of fission products, cooling time and etc. which are required in the fuel loading control of reactors and special nuclear materials accountancy from the view point of safe guard. Although, some available data are given about uranium dioxide fuels, few data are given about uranium and plutonium dioxide mixtures (MOX fuels). Especially, there is few data about MOX fuels which are irradiated in thermal reactors and cooled more than ten years. Gamma-ray spectra are measured for PuO 2 -UO 2 fuel rods (IFA-159, IFA-160) which are irradiated at HBWR in Norway up to 9,420 and 5,340MWd/t respectively. Gamma-ray spectra had been measured about the two fuels ten years ago at the spent fuel pond of Japan Demonstration Reactor (JPDR). The objectives of this measurement is to know how decayed the gamma-ray spectra in these ten years and some fission products are there which are effective to estimate burnup rate of spent MOX fuels. (author)

Effects of gamma irradiations on reactive pulsed laser deposited vanadium dioxide thin films

Energy Technology Data Exchange (ETDEWEB)

Madiba, I.G., E-mail: madibagiven@gmail.com [UNESCO-UNISA Africa Chair in Nanosciences/Nanotechnology, College of Graduate Studies, University of South Africa (UNISA), Muckleneuk Ridge, P O Box 392, Pretoria (South Africa); Empa, Swiss Federal Laboratories Materials Science and Technology, CH-8600 Dübendorf (Switzerland); Émond, N.; Chaker, M. [Institut National de la Recherche Scientifique (INRS),1650 Blvd. Lionel-Boulet, Varennes, Québec J3X1S2 (Canada); Thema, F.T. [UNESCO-UNISA Africa Chair in Nanosciences/Nanotechnology, College of Graduate Studies, University of South Africa (UNISA), Muckleneuk Ridge, P O Box 392, Pretoria (South Africa); iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, PO Box 722, Somerset West, Western Cape Province (South Africa); Tadadjeu, S.I. [iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, PO Box 722, Somerset West, Western Cape Province (South Africa); Department of Electrical, Electronics and Computer Engineering, French South African Institute of Technology/Cape Peninsula University of Technology, Bellville campus, PO Box 1906, Bellville, 7530 (South Africa); Muller, U.; Zolliker, P. [Empa, Swiss Federal Laboratories Materials Science and Technology, CH-8600 Dübendorf (Switzerland); Braun, A. [ETH Zurich, Swiss Federal Institute of Technology, CH-8057, Zurich (Switzerland); Empa, Swiss Federal Laboratories Materials Science and Technology, CH-8600 Dübendorf (Switzerland); Kotsedi, L. [iThemba LABS-National Research Foundation, 1 Old Faure Road, Somerset West 7129, PO Box 722, Somerset West, Western Cape Province (South Africa); and others

2017-07-31

Highlights: • Synthesis of VO{sub 2} thin films by Reactive pulsed laser deposition has been achieved. • Properties VO{sub 2} remain mainly unaffected when subjected to gamma ray doses similar to those encountered during space missions. • The long range crystal structure of VO{sub 2} remains intact upon irradiation on different doses up to 100 kGy. • XPS reveals a shift from V{sup 4+} to V{sup 5+} oxidation state upon irradiation, due to the frenkel pair formation on the surface. • Irradiated films show the characteristic SMT of VO{sub 2}, although the electrical and optical properties are slightly affected. - Abstract: Vanadium oxide films are considered suitable coatings for various applications such as thermal protective coating of small spacecrafts because of their thermochromic properties. While in outer space, such coating will be exposed to cosmic radiations which include γ-rays. To study the effect of these γ-rays on the coating properties, we have deposited vanadium dioxide (VO{sub 2}) films on silicon substrates and subjected them to extensive γ-irradiations with typical doses encountered in space missions. The prevalent crystallographic phase after irradiation remains the monoclinic VO{sub 2} phase but the films preferential orientation shifts to lower angles due to the presence of disordered regions caused by radiations. Raman spectroscopy measurements also evidences that the VO{sub 2} structure is slightly affected by gamma irradiation. Indeed, increasing the gamma rays dose locally alters the crystalline and electronic structures of the films by modifying the V–V inter-dimer distance, which in turns favours the presence of the VO{sub 2} metallic phase. From the XPS measurements of V2p and O1s core level spectra, an oxidation of vanadium from V{sup 4+} towards V{sup 5+} is revealed. The data also reveal a hydroxylation upon irradiation which is corroborated by the vanishing of a low oxidation state peak near the Fermi energy in the

EFFECTS OF TRITIUM GAS EXPOSURE ON THE GLASS TRANSITION TEMPERATURE OF EPDM ELASTOMER AND ON THE CONDUCTIVITY OF POLYANILINE

Energy Technology Data Exchange (ETDEWEB)

Clark, E; Marie Kane, M

2008-12-12

Four formulations of EPDM (ethylene-propylene diene monomer) elastomer were exposed to tritium gas initially at one atmosphere and ambient temperature for between three and four months in closed containers. Material properties that were characterized include density, volume, mass, appearance, flexibility, and dynamic mechanical properties. The glass transition temperature was determined by analysis of the dynamic mechanical property data per ASTM standards. EPDM samples released significant amounts of gas when exposed to tritium, and the glass transition temperature increased by about 3 C. during the exposure. Effects of ultraviolet and gamma irradiation on the surface electrical conductivity of two types of polyaniline films are also documented as complementary results to planned tritium exposures. Future work will determine the effects of tritium gas exposure on the electrical conductivity of polyaniline films, to demonstrate whether such films can be used as a sensor to detect tritium. Surface conductivity was significantly reduced by irradiation with both gamma rays and ultraviolet light. The results of the gamma and UV experiments will be correlated with the tritium exposure results.

Effects of {gamma}-ray irradiation on the C-V and G/{omega}-V characteristics of Al/SiO{sub 2}/p-Si (MIS) structures

Energy Technology Data Exchange (ETDEWEB)

Doekme, Ilbilge [Science Education Department, Faculty of Education, Ahi Evran University, Kirsehir (Turkey)], E-mail: ilbilgedokme@gazi.edu.tr; Durmus, Perihan; Altindal, Semsettin [Physics Department, Faculty of Arts and Sciences, Gazi University, 06500 Teknikokullar, Ankara (Turkey)

2008-03-15

The effect of the {sup 60}C{sub o} ({gamma}-ray) exposure on the electrical characteristics of Al/SiO{sub 2}/p-Si (MIS) structures has been investigated using capacitance-voltage (C-V) and conductance-voltage (G/{omega}-V) measurements. The MIS structures were stressed with a bias of 0 V during {sup 60}C{sub o}{gamma}-sources irradiation with the total dose range from 0 to 25 kGy. The C-V and G/{omega}-V characteristics were measured at 500 kHz and room temperature before and after {sup 60}C{sub o}{gamma}-ray irradiation. The results indicated that {gamma}-irradiation caused an increase in the barrier height {phi}{sub B}, interface states N{sub ss} and depletion layer width W{sub D} obtained from reverse bias C-V measurements. The series resistance R{sub s} profile for various radiation doses was obtained from forward and reverse bias C-V and G/{omega}-V measurements. Both C-V and G/{omega}-V characteristics indicate that the total dose radiation hardness of MIS structures may be limited by the decisive properties of the SiO{sub 2}/Si interface to radiation-induced damage. After {gamma}-irradiation, the decrease in capacitance of MIS structure results in the increase in the semiconductor depletion width.

Effect of gamma-ray irradiation on the surface states of MOS tunnel junctions

Science.gov (United States)

Ma, T. P.; Barker, R. C.

1974-01-01

Gamma-ray irradiation with doses up to 8 megarad produces no significant change on either the C(V) or the G(V) characteristics of MOS tunnel junctions with intermediate oxide thicknesses (40-60 A), whereas the expected flat-band shift toward negative electrode voltages occurs in control thick oxide capacitors. A simple tunneling model would explain the results if the radiation-generated hole traps are assumed to lie below the valence band of the silicon. The experiments also suggest that the observed radiation-generated interface states in conventional MOS devices are not due to the radiation damage of the silicon surface.

Effect of gamma-ray on olive fruits quality, enzyme activities and issued oil

International Nuclear Information System (INIS)

Mejri, Sonia

2007-01-01

The results described in the present work concern the study of changes in gamma ray irradiated olive fruit (Tunisian variety: C hemlali ) quality along the storage time processing and the quality of olive oil issued. The study focused on the changes related to the microbiological, physico-chemical properties, as well as pectinase activities in olive after irradiation. We also have been interested in the final product quality after oil extraction. The results of non irradiated olives were presented for comparative purposes. Mature olive fruits were treated with 0.5, 1 and 1.5 kGy gamma ray radiation. Olive fruits were then stored for one month. Irradiation at 1.5 kGy allows the almost total destruction of the total aerobic germs, yeasts and moulds. Concerning physico-chemical parameters, the increase of the dose level generated an improvement in water retention capacity and decreased the rate of polysaccharides hydrolyzes olives. Moreover, the irradiation dose of 0.5 kGy induced the increase in pectinase activities thanks to the improvement of the protein extraction yield. The gamma ray irradiation of olive fruit seems to not decrease olive oil oxidative stability in the studied samples. Finally, gamma ray radiation was able to improve the yield of extraction of the oil and insaponifiable fraction as polyphenols and beta carotenes. (Author)

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

Energy Technology Data Exchange (ETDEWEB)

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

1996-03-01

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

Comparative effects of gamma-rays and electron beams on peroxide formation in phosphatidylcholine

International Nuclear Information System (INIS)

Todoriki, S.; Hayashi, T.

1994-01-01

Phosphatidylcholine was irradiated in the state of a film or liposome with gamma-rays or electron beams, and the amount of peroxide was determined to compare the effects of the two types of radiation. The amounts of peroxide formed in both the film and liposome with gamma-rays were significantly larger than those with electron beams, when the samples were irradiated at the same dose. Proteins such as bacteriorhodopsin reduced the degree of peroxide formation in liposome, and the effect of gamma-rays was much larger than that of electron beams, even in the presence of protein. The results of the present investigation indicate that the effects of gamma-rays on peroxide formation in phosphatidylcholine were significantly larger than those of electron beams, irrespective of the state of the lipid

Effects of gamma irradiation on raw materials and perfumes

International Nuclear Information System (INIS)

Guillot, M.; Pelpel, A.

1983-01-01

In order to enlight the strange problem of apparent perfume stability observed in manufactured talc powders sterilized by gamma rays, investigations were made on samples of odorant substances (raw materials, essential oils, or elaborated mixtures). As a rule, no immediate adulteration of olfactive caracteristics resulted at once from gamma irradiation. In several cases, a stabilizing effect appeared immediately and remained effective after long storage in various conditions (of temperature, or light, or oxygen exposure). This unexpected effect seems to be in accordance with previous experiments on gamma or electron irradiations of mixtures of organic molecules, reported in litterature: a mutual inhibition was observed to take place [fr

Study of the oxidation and of the mechanical behavior of irradiated elastomers: consequences of the electronic irradiation on the electrical cables during the occurring of a pressurized water reactor accident

International Nuclear Information System (INIS)

Corbin, D.

2001-01-01

This thesis contributes to a better understanding and predictions of the consequences of electronic irradiation on the electrical cables when an accident of a pressurized water reactor occurs. We studied the radio-oxidation and the mechanical behaviour of two irradiated elastomers, EPDM (ethylene-propylene-hexadiene 1,4 terpolymer) and hypalon (chloro-sulfonated polyethylene), used respectively as insulating and sheath material of the cable. In the first part, the conditions of exposure to radiation during an accident are presented. They induce a very heterogeneous dose profile in the cable because of the low range of the involved electrons. This situation contrasts with normal operating conditions of the power plant and corresponding qualification tests. In the latter case, the profile is uniform since it is deposited by γ - rays with large ranges. The second part focuses on degradation under presence of oxygen, with typical dose and dose rate conditions for an accident. Thin films of the two elastomers (basic and formulated polymers) are irradiated by electrons and the oxidation products, and their concentrations are determined chemically. The influence, on the kinetics of radio-oxidation, of three parameters typical for the irradiation, the oxygen pressure, the dose rate and the dose is presented there. The effect of antioxidants is studied in the case of EPDM. The third part describes the results concerning the experimental simulation of the dose profile during the accident on thick plates of two formulated elastomers. The evolution of the breaking mechanical properties, as a function of dose and the thickness of the plates, is presented and analysed in correlation with the oxidation profiles. (author)

Effects of gamma irradiation on protocorm-like bodies of cattleya alliances

International Nuclear Information System (INIS)

Thammasiri, K.

1996-01-01

Induced mutations by gamma irradiation can be one of the promising methods for orchid breeding. Protocorm - like bodies (PLBs) of Brassolaeliocattleya (Blc.) Alma kee and Blc. Greenwich were established from in vitro apical and axillary buds of young shoots in Vacin and Went (1949) liquid medium supplemented with 150 ml/l coconut water. PLBs were irradiated with gamma rays at 0, 20, 60, 80, 110 and 130 Gray (Gy). Doses between 80 and 110 Gy were suitable to apply for induced mutations in both cultivars. Another experiment with more samples was conducted. Gamma rays were applied at 0, 70, 100 and 130 Gy. The results showed that irradiated PLBs of both cultivars had slow growth rate and some PLBs turned brown and died. A dose of 70 Gy was suitable for induced mutation. More severe effects were observed when higher doses had been applied

Effect of the gamma irradiation on the bio-sorption of Cr (Vi) by orange peel

International Nuclear Information System (INIS)

Lugo L, V.; Barrera D, C. E.; Sanchez M, V.; Urena N, F.

2009-01-01

The orange peel (Citrus sp.) is a bioadsorbent that contains functional groups able to remove Cr (Vi). To study the effect of gamma irradiation in the sorption capacity, the Nn materials were irradiated with gamma rays using a Co 60 source to dose from 10 to 3500 KGy (Nlγ). The biomass irradiation with gamma rays was successful since it increased the hexavalent chromium removal obtaining a maximum removal percentage of 100%. Sorption isotherms were realized to determine the concentration effect of initial Cr (Vi), the ph effect of the solution and the relationship m/v. (Author)

Comparative nephrotoxicity of native or Co-60 gamma rays irradiated crotoxin in mice

Energy Technology Data Exchange (ETDEWEB)

Rocha, Andre Moreira; Alves, Glaucie J.; Aires, Raquel da Silva; Turibio, Thompson O.; Thomazi, Gabriela O. Coelho; Spencer, Patrick J.; Nascimento, Nanci do, E-mail: andrerocha@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Nascimento-Rocha, Josefa M.; Magalhaes Filho, Asterio Souza, E-mail: 0304@prof.itpacporto.com.br [Instituto Tocantinense Presidente Antonio Carlos Porto (ITPAC), Porto Nacional, TO (Brazil)

2015-07-01

Snake venoms are complex mixtures of proteins and peptides with a wide spectrum of physiological targets such as the blood coagulation and cardiovascular systems and the motor end plate among others. Acute renal failure is a common complication in accidents with the South American rattlesnake. The toxin involved in this pathology is the crotoxin, a major component of the venom in terms of concentration and toxicity. Snake venoms, when irradiated with {sup 60}Co gamma rays present a significant decrease in toxicity while the immunogenic properties of its components are preserved. The use of irradiated venom is an attractive alternative for antisera production since it might reduce the appearance of renal lesions improving the welfare and lifespan of those animals employed on antivenom production. At the present work, we have compared the effects of native and irradiated crotoxin on the mice renal function. Tubular lesions were observed in all the samples from the animal group injected with native crotoxin. Animals injected with the irradiated toxin presented alteration only after 30 minutes and 1 hour after injection. These data suggest that the onset of the renal lesions is delayed and that the severity of the lesions might be lower when using irradiated crotoxin. (author)

Thermal characterization of the HDPE/LDPE blend (10/90) irradiated using gamma-rays

Energy Technology Data Exchange (ETDEWEB)

Puig, C.C., E-mail: cpuig@usb.v [Universidad Simon Bolivar, Departamento de Ciencia de los Materiales, Grupo de Polimeros USB, Apdo. 89000, Caracas 1080-A (Venezuela, Bolivarian Republic of); Albano, C., E-mail: calbano@ivic.v [Instituto Venezolano de Investigaciones Cientificas (IVIC), Centro de Quimica, Laboratorio de Polimeros, Apdo. 21827, Caracas 1020-A (Venezuela, Bolivarian Republic of); Universidad Central de Venezuela, Facultad de Ingenieria, Escuela de Ingenieria Quimica, Laboratorio de Polimeros, Caracas (Venezuela, Bolivarian Republic of); Laredo, E. [Universidad Simon Bolivar, Departamento de Fisica, Grupo de Fisica de Materiales Amorfos y Cristalinos, Apdo. 89000, Caracas 1080-A (Venezuela, Bolivarian Republic of); Quero, E. [Universidad Simon Bolivar, Departamento de Ciencia de los Materiales, Grupo de Polimeros USB, Apdo. 89000, Caracas 1080-A (Venezuela, Bolivarian Republic of); Karam, A. [Instituto Venezolano de Investigaciones Cientificas (IVIC), Centro de Quimica, Laboratorio de Polimeros, Apdo. 21827, Caracas 1020-A (Venezuela, Bolivarian Republic of)

2010-05-01

Gamma irradiation effect over the properties of slow cooled and fast cooled HDPE/LDPE 10/90 blend was studied. The blend and the neat polyethylenes were irradiated at room temperature in the presence of air using the following doses (4.8 kGy/h): 0, 50, 150, 400 and 1000 kGy. Differential scanning calorimetry (DSC) experiments were carried out using the following heating rates: 5, 10 and 20 deg. C/min. DSC results for the slow and fast cooled blend showed traces with three melting peaks and with increasing irradiation dose two melting peaks were obtained, i.e. the high melting peak shifts toward lower temperatures to merge with the intermediate melting peak into one endotherm. No changes in crystal structure by X-ray diffraction were found as a result of samples irradiation. Radiation crosslinking prevents crystal rearrangements during heating in the DSC. Gel content and melt flow index (MFI) measurements showed that radiation induced a high degree of crosslinking for all samples; gel content values were above 50% and a drop of more than 90% in the MFI was found. Irradiation of slow cooled samples resulted in larger values of gel content and lower MFI values than for fast cooled samples, mainly because of the higher degree of crosslinking for the former.

Comparative nephrotoxicity of native or Co-60 gamma rays irradiated crotoxin in mice

International Nuclear Information System (INIS)

Rocha, Andre Moreira; Alves, Glaucie J.; Aires, Raquel da Silva; Turibio, Thompson O.; Thomazi, Gabriela O. Coelho; Spencer, Patrick J.; Nascimento, Nanci do; Nascimento-Rocha, Josefa M.; Magalhaes Filho, Asterio Souza

2015-01-01

Snake venoms are complex mixtures of proteins and peptides with a wide spectrum of physiological targets such as the blood coagulation and cardiovascular systems and the motor end plate among others. Acute renal failure is a common complication in accidents with the South American rattlesnake. The toxin involved in this pathology is the crotoxin, a major component of the venom in terms of concentration and toxicity. Snake venoms, when irradiated with 60 Co gamma rays present a significant decrease in toxicity while the immunogenic properties of its components are preserved. The use of irradiated venom is an attractive alternative for antisera production since it might reduce the appearance of renal lesions improving the welfare and lifespan of those animals employed on antivenom production. At the present work, we have compared the effects of native and irradiated crotoxin on the mice renal function. Tubular lesions were observed in all the samples from the animal group injected with native crotoxin. Animals injected with the irradiated toxin presented alteration only after 30 minutes and 1 hour after injection. These data suggest that the onset of the renal lesions is delayed and that the severity of the lesions might be lower when using irradiated crotoxin. (author)

Use of gamma irradiation for microbial inactivation of buckwheat flour and buckwheat food products, 1

International Nuclear Information System (INIS)

Matsuhashi, Tetsujiro; Oh-hinata, Hiroshi; Muramatsu, Nobuyuki; O-hara, Tadahiko; Itoh, Hitoshi; Saito, Makoto.

1986-01-01

In an attempt to develop a feasible method for improving shelf-life extension of fresh 'soba' noodles, the usefulness of gamma irradiation was preliminarily investigated. Microorganism counts decreased to less than 10 2 per gram by irradiating gamma rays of 0.5 Mrad to buckwheat grains with hulls (Material I), industrially processed buckwheat flours (Material II), and uncooked 'soba' noodles packed in a plastic film bag (Material III). For Material II, the effective dose to decrease 90 % of the microorganism counts was 0.1 Mrad, and heat-resistant microorganism counts decreased to 10 or less per gram with gamma rays of 0.2 - 0.5 Mrad. Flavor in either Material II or Material III was not changed by irradiation; by contraries, enhanced 'soba'-like flavor was rarely observed. Although gamma-irradiation decreased the viscosity of Material II, it hardly exerted an effect on the process of making noodles. The texture of Material III became degraded by irradiation. The results suggest the feasibility of gamma irradiation in the use of inactivation of microorganisms. (Namekawa, K.)

Feasibility of applying gamma irradiation as disinfestation technique on date fruits in respect to nutritional value that is affected by disinfesting gamma ray doses

International Nuclear Information System (INIS)

Ahmed, El-Sayed S.

1976-01-01

Infested and non-infested dry date fruits (Phonex dactylifera), Abrimi variety (9.2% moisture), with Ephestia cautella Walker were irradiated for 0, 15, 20 and 40 Krad gamma ray doses emitted from Co-60 source with 1.36 x 10-rad/h. as a dose rate. Irradiated fruits were stored at room temperature, at 20-25 0 C and 85-95% R.H., in packages to avoid reinfestation. A dose of 20 Krad is 100 percent effective in preventing the emergency of eggs, larva, and pupae in fruits as reflected by zero per cent emergency count for live adults. Also, this dose was found to be lethal for adult stage of the insect. On the other hand, 2 Krad dose does not produce significant changes in the nutritional qualities of fruits, as measured by chemical analytical means for carbohydrates, protein and amino acids, directly after irradiation as well as at 2, 4 and 6 months storage. The triangular tests show that irradiation treatments even with 4 Krad exerted no determinal effect upon the sensory qualities of stored irradiated date fruits. These results point out the feasibility of applying gamma irradiation, 20 Krad, as disinfestation technique against Ephestia cautella Walker in dry date fruits without exerting any effect on the nutritional value

Survival of embryo irradiated with gamma rays by embryo culture in Brassica pekinensis Rupr

International Nuclear Information System (INIS)

Moue, T.

1984-01-01

The effect of irradiation on the survival rates and embryonic development of Brassica pekinensis RUPR. (Varieties; Kashin, Kohai 65 nichi and kairyochitose) was investigated. The purpose of this study was to seek ways of increasing the survival rates of embryos such as B.oleracea obtained through embryo culture techniques after irradiation doses affecting seed fertility and germination, for the purpose of increasing mutation rates. Embryos at different developmental stages ranging from the globular to the early heart stages were irradiated with 20 KR of gamma rays at the daily rate 0L 20 KR or 10 KR (Fig.1 and Table 1). The embryos were excised from ovules 4 to 10 days after irradiation and cultured on White's medium. The shooting and rooting rates on the 34th day of culture were higher at the dose of 10 KR/day than 20 KR/day and were lower when the materials were irradiated at the young embryonic stage (Table 3). Varietal differences in the shooting and rooting rates were also observed. The irradiated embryos survived mainly in the state of callus. It was concluded that the embryo culture technique was successful when applied to irradiated embryos excised at the young embryonic stage and that the technique affected B.pekinensis less than B.oleracea

Effect of gamma irradiation on the sensitivities of escherichia coli at deep frozen conditions

International Nuclear Information System (INIS)

Takigami, Machiko; Ito, Hitoshi

1996-01-01

Phosphate buffer suspensions of three strains of Escherichia coli were irradiated with gamma-rays at room temperature and deep frozen conditions. They were inoculated on MacConkey agar plates to see the comparative sensitivities to the irradiation. Compared to the irradiation at room temperature, the sensitivities of the strains decreased by irradiation at deep frozen conditions. Addition of glycerol to the E. coli suspensions decreased the sensitivities of E. coli to gamma-rays not only at room temperature but also at deep frozen conditions. These phenomena were elucidated by the decrease of production and mobility of OH radicals at deep frozen conditions. (author)

Results on Neutron and Gamma Irradiation of Electrolytic Tilmeters

International Nuclear Information System (INIS)

Calderon, A.; Calvo, E.; Figueroa, C. F.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Vila, I.; Virto, A. L.; Alberdi, J.; Arce, P.; Barcala, J. M.; Fernando, A.; Fuentes, J.; Josa, M. I.; Luque, J. M.; Molinero, A.; Navarrate, J.; Valdivieso, P.; Fenyvesi, A.; Molnar, J.

2004-01-01

We report on irradiation studies done to a sample of high precision electrolytic tiltmeters with gamma-rays, up to a maximum dose of 150 kGy, an neutrons, up to a maximum fluence 1.5x10''14 cm''2. The effect of the irradiation on their performance is discussed. (Author) 19 refs

Radiosensitizing effect of nitric oxide in tumor cells and experimental tumors irradiated with gamma rays and proton beams; Efecto radiosensibilizador del oxido nitrico en celulas tumorales y en tumores experimentales irradiados con radiacion gamma y con haces de protones

Energy Technology Data Exchange (ETDEWEB)

Policastro, Lucia L; Duran, Hebe; Molinari, Beatriz L [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Radiobiologia; Schuff, Juan A; Kreiner, Andres J; Burlon, Alejandro A; Debray, Mario E; Kesque, Jose M; Ozafran, Mabel J; Vazquez, Monica E [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Fisica; Davidson, Jorge; Davidson, Miguel [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires (Argentina); Somacal, Hector R; Valda, Alejandro A [Universidad Nacional de General San Martin , Villa Ballester (Argentina). Escuela de Ciencia y Tecnologia

2003-07-01

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

High dose gamma-ray standard

International Nuclear Information System (INIS)

Macrin, R.; Moraru, R.

1999-01-01

The high gamma-ray doses produced in a gamma irradiator are used, mainly, for radiation processing, i.e. sterilization of medical products, processing of food, modifications of polymers, irradiation of electronic devices, a.s.o. The used absorbed doses depend on the application and cover the range 10 Gy to 100 MGy. The regulations in our country require that the response of the dosimetry systems, used for the irradiation of food and medical products, be calibrated and traceable to the national standards. In order to be sure that the products receive the desired absorbed dose, appropriate dosimetric measurements must be performed, including the calibration of the dosemeters and their traceability to the national standards. The high dose gamma-ray measurements are predominantly based on the use of reference radiochemical dosemeters. Among them the ferrous sulfate can be used as reference dosemeter for low doses (up to 400 Gy) but due to its characteristics it deserves to be considered a standard dosemeter and to be used for transferring the conventional absorbed dose to other chemical dosemeters used for absorbed doses up to 100 MGy. The study of the ferrous sulfate dosemeter consisted in preparing many batches of solution by different operators in quality assurance conditions and in determining for all batches the linearity, the relative intrinsic error, the repeatability and the reproducibility. The principal results are the following: the linear regression coefficient: 0.999, the relative intrinsic error: max.6 %, the repeatability (for P* = 95 %): max.3 %, the reproducibility (P* = 95%): max.5 %. (authors)

Action of minute dosis of gamma rays on gestation of mice

International Nuclear Information System (INIS)

Templier, J.; Maudouyt, M.A.; Charpenteau, M.; Bonnet, J.

1978-01-01

Female mice were irradiated with 10 rads of 60 Co gamma ray, 7 hours after mating. This low dose induces a decrease in implantation number, and alive foetus number and is followed by a lower number of corpora lutea. These results to seem to show an effect of gamma irradiation on ovary and embryonic development [fr

First results on irradiation of ceramic parallel plate chambers with gammas and neutrons

International Nuclear Information System (INIS)

Arefiev, A.; Bencze, Gy.L.; Bizzeti, A.; Choumilov, E.; Civinini, C.; Dajko, G.; D'Alessandro, R.; Fenyvesi, A.; Ferrando, A.; Fouz, M.C.; Iglesias, A.; Ivochkin, V.; Josa, M.I.; Malinin, A.; Meschini, M.; Molnar, J.; Pojidaev, V.; Salicio, J.M.; Tanko, L.; Vesztergombi, G.

1996-01-01

Ceramic parallel plate chambers were irradiated with gamma rays and neutrons. Results on radiation resistance are presented after 60 Mrad gamma and 0.5.10 16 neutrons per cm 2 irradiation of the detector surface. Results of activation analysis of chambers made of two different ceramic materials are also presented. (orig.)

The alterations in high density polyethylene properties with gamma irradiation

Science.gov (United States)

Zaki, M. F.; Elshaer, Y. H.; Taha, Doaa. H.

2017-10-01

In the present investigation, high density polyethylene (HDPE) polymer has been used to study the alterations in its properties under gamma-irradiation. Physico-chemical properties have been investigated with different spectroscopy techniques, Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), biocompatibility properties, as well as, mechanical properties change. The FT-IR analysis shows the formation of new band at 1716 cm-1 that is attributed to the oxidation of irradiated polymer chains, which is due to the formation of carbonyl groups (C˭O). XRD patterns show that a decrease in the crystallite size and increase in the Full Width at Half Maximum (FWHM). This means that the crystallinity of irradiated samples is decreased with increase in gamma dose. The contact angle measurements show an increase in the surface free energy as the gamma irradiation increases. The measurements of mechanical properties of irradiated HDPE samples were discussed.

Gamma ray generator

Science.gov (United States)

Firestone, Richard B; Reijonen, Jani

2014-05-27

An embodiment of a gamma ray generator includes a neutron generator and a moderator. The moderator is coupled to the neutron generator. The moderator includes a neutron capture material. In operation, the neutron generator produces neutrons and the neutron capture material captures at least some of the neutrons to produces gamma rays. An application of the gamma ray generator is as a source of gamma rays for calibration of gamma ray detectors.

Low temperature gamma-ray irradiation effects on polymer materials

International Nuclear Information System (INIS)

Kudoh, Hisaaki; Kasai, Noboru; Sasuga, Tsuneo; Seguchi, Tadao

1995-01-01

The gamma radiation induced degradation of glass fiber reinforced plastic (GFRP) and polymethylmethacrylate (PMMA) at 77K was examined by flexural test and gas analysis after irradiation and compared by the irradiation at room temperature. The decrease in flexural strength at break was much less at 77K than at RT. The evolution of CH 4 , CO and CO 2 was also depressed at 77K. The temperature dependence of the degradation closely relates to the local molecular motion of matrix resin during irradiation. Polytetrafluoroethylene (PTFE) was also studied by irradiation at RT, 77K and 4K in terms of tensile elongation and molecular weight. The degradation was much less at 77K and 4K than at RT, and the same between 77K and 4K. (author)

Use of gamma irradiation for prolonging shelf life of Garden pea (Pisum sativum L.)

International Nuclear Information System (INIS)

Mehta, A.K.; Nair, Reena

2008-01-01

Garden pea pods of variety Arkel were irradiated with 5 doses of 60 Co gamma rays ranging from 0.5-3 kGy and stored at ambient temperature up to 9 days along with control to study the effect of radiation in prolonging shelf life of pea pods and stabilizing its market demand. Physiological weight loss percentage decrease as the doses of gamma radiation increased. Minimum weight loss was noted in pods treated with 3 kGy gamma radiation as compared to control. Decay loss percent showed inverse relation with dose of gamma radiation. The minimum decay loss was recorded in 3 kGy and the organisms identified for decay loss were Alternaria and Cladosporium species of fungi. With regard to sugar content, pea pods irradiated with 1 kGy gamma rays recorded maximum sugar content. Pods irradiated with 0.5 kGy and 1 kGy gamma rays retained their green colour for a long period (up to 9th day of storage). Based on 9 point's hedonic scale the overall acceptability for appearance, taste and texture was observed in 1 kGy treatment. (author)

Neutron and gamma irradiation effects on power semiconductor switches

Science.gov (United States)

Schwarze, G. E.; Frasca, A. J.

1990-01-01

The performance characteristics of high power semiconductor switches subjected to high levels of neutron fluence and gamma dose must be known by the designer of the power conditioning, control and transmission subsystem of space nuclear power systems. Location and the allowable shielding mass budget will determine the level of radiation tolerance required by the switches to meet performance and reliability requirements. Neutron and gamma ray interactions with semiconductor materials and how these interactions affect the electrical and switching characteristics of solid state power switches is discussed. The experimental measurement system and radiation facilities are described. Experimental data showing the effects of neutron and gamma irradiation on the performance characteristics are given for power-type NPN Bipolar Junction Transistors (BJTs), and Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs). BJTs show a rapid decrease in gain, blocking voltage, and storage time for neutron irradiation, and MOSFETs show a rapid decrease in the gate threshold voltage for gamma irradiation.

Determination the lethal dose of ascaris lumbricoides ova by gamma irradiation

International Nuclear Information System (INIS)

Shamma, M.; Al-Adawi, M.; Sharabi, N.

2002-11-01

The lethal gamma irradiation dose of ascaris lumbricoides which collected from Damascus Sewage water Plant was determined. Ascaris lumbricoides ova were treated with several gamma irradiation doses with (0.1, 0.2, 0.3, 0.4,...and 1.5 KGy). No morphological changes were observed on the eggs when directly examined microscopically after irradiation. However after two weeks of incubation at 37 degree centigrade the cell contents of the eggs which irradiated with 0.5 KGy and beyond were fragmented and scattered in the whole eggs and no larvae were observed after eight weeks of incubation. It is concluded that the dose 0.5 my be considered as the dose of choice if sewage water is to be treated by gamma rays. (author)

Determination the lethal dose of ascaris lumbricoides ova by gamma irradiation

CERN Document Server

Shamma, M A; Sharabi, N

2002-01-01

The lethal gamma irradiation dose of ascaris lumbricoides which collected from Damascus Sewage water Plant was determined. Ascaris lumbricoides ova were treated with several gamma irradiation doses with (0.1, 0.2, 0.3, 0.4,...and 1.5 KGy). No morphological changes were observed on the eggs when directly examined microscopically after irradiation. However after two weeks of incubation at 37 degree centigrade the cell contents of the eggs which irradiated with 0.5 KGy and beyond were fragmented and scattered in the whole eggs and no larvae were observed after eight weeks of incubation. It is concluded that the dose 0.5 my be considered as the dose of choice if sewage water is to be treated by gamma rays.

Modulating effect of dimethylbenzanthracene on gamma-ray mutagenesis in the soybean test system

Energy Technology Data Exchange (ETDEWEB)

Fujii, T. [National Inst. of Genetics, Mishima, Shizuoka (Japan); Inoue, T.

1987-10-15

Dimethylbenzanthracene (DMBA), a strong tumor initiator, did not show mutagenic activity in the soybean test system either alone or in combination with tumor promoter, TPA. In combination treatments with DMBA and gamma-rays, the mutagenicity of gamma-rays was not affected by post-treatment with DMBA. However, DMBA pre-treatment clearly reduced gammaray-ray induced spotting frequency, suggesting that DMBA affects mutagenesis in gamma-irradiated soybean cells.

Application for plasma diagnostics with D(α, γ)6Li gamma-ray

International Nuclear Information System (INIS)

Ochiai, Kentaro; Kubota, Naoyoshi; Nishitani, Takeo; Taniike, Akira; Kitamura, Akira

2006-01-01

The gamma ray measurement from fusion plasma is one of the important techniques to clarify fast ion properties in plasma. Some observation of the gamma-ray in JET plasma was reported. 12 C(d, pγ) 13 C and 9 Be(α, nγ) 12 C reactions on the JET observation are mainly recommended as the actual prospective nuclear reaction on the gamma-ray measurement. However, it is thought that the gamma-ray observation by means of these reactions significantly depends on the conditioning (i.e. densities of the beryllium and carbon in plasma). Therefore, it is also important to examine the availabilities concerning the methods of gamma ray. We have tried to measure the 2.18 MeV gamma ray of D(α, γ) 6 Li reaction and the properties of the another gamma ray emission by MeV-He ++ beam irradiation experiment. (author)

Prompt gamma-ray imaging for small animals

Science.gov (United States)

Xu, Libai

Small animal imaging is recognized as a powerful discovery tool for small animal modeling of human diseases, which is providing an important clue to complete understanding of disease mechanisms and is helping researchers develop and test new treatments. The current small animal imaging techniques include positron emission tomography (PET), single photon emission tomography (SPECT), computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound (US). A new imaging modality called prompt gamma-ray imaging (PGI) has been identified and investigated primarily by Monte Carlo simulation. Currently it is suggested for use on small animals. This new technique could greatly enhance and extend the present capabilities of PET and SPECT imaging from ingested radioisotopes to the imaging of selected non-radioactive elements, such as Gd, Cd, Hg, and B, and has the great potential to be used in Neutron Cancer Therapy to monitor neutron distribution and neutron-capture agent distribution. This approach consists of irradiating small animals in the thermal neutron beam of a nuclear reactor to produce prompt gamma rays from the elements in the sample by the radiative capture (n, gamma) reaction. These prompt gamma rays are emitted in energies that are characteristic of each element and they are also produced in characteristic coincident chains. After measuring these prompt gamma rays by surrounding spectrometry array, the distribution of each element of interest in the sample is reconstructed from the mapping of each detected signature gamma ray by either electronic collimations or mechanical collimations. In addition, the transmitted neutrons from the beam can be simultaneously used for very sensitive anatomical imaging, which provides the registration for the elemental distributions obtained from PGI. The primary approach is to use Monte Carlo simulation methods either with the specific purpose code CEARCPG, developed at NC State University or with the general purpose

A new type gamma-ray spectrum monitoring system

CERN Document Server

Cheng Bo; Zhou Jian Bin; Zhang Zhi Ming; Tong Yun Fu

2002-01-01

This new radiation monitoring system can be used to monitor the radiation of building materials and the radiation of atmosphere, to explore and evaluate rock for building in the field, and this system can be used to monitor the gamma irradiation near the nuclear establishments in the average situation and in the serious situation of the radiation incident have happened. The control core of this monitoring system is SCM-AT89C52, and gamma-ray sensing head consists of scintillator phi 50 mm x 50 mm NaI(Tl) and PMT GDB44. This system can be used to measure the whole gamma-ray spectrum of 256 channels

The effects of gamma rays and genotypes on sunflower organogenesis traits [Helianthus annuus L.

International Nuclear Information System (INIS)

Rachid Al-Chaarani, G.; Gentzbittel, L.; Berrault, G.; Lenoble, S.; Sarrafi, A.

2004-01-01

Seeds of two inbred lines (AS613 and AS616) and their hybrid were irradiated with seven gamma rays doses (5, 15, 25, 35, 45, 55 and 65 Grays). Organogenesis traits were studied for all irradiated seeds as well as non irradiated ones used as control. The experiment was designed as a randomized complete block with three replications. Each replication consisted of 16 Petri dishes with four explants per gamma rays dose and per genotype. The regeneration ability of genotypes and the effects of gamma rays on regeneration were scored by assessing the percentage of explants forming shoots (ES/100E), the average number of shoots per explant shooting (S/ES) and the average number of shoots per explant plated (S/E). Genetic variability was observed among the three genotypes for all studied traits. The effect of irradiation and the interaction between genotype and irradiation were also significant for all the studied traits. Heterosis, when the hybrid was compared with the mean of the two parents, was significant for the different gamma rays doses in all traits except for 15 and 55 Grays, which were not significant for the percentage of explants forming shoots (ES/100E). Seed irradiation by 5 and 15 Grays is likely to have a significant effect by increasing the regeneration ability by cotyledon culture in sunflower [it

Effect of gamma irradiation on storability of strawberry (Fragaria sp)

Energy Technology Data Exchange (ETDEWEB)

Al-Bachir, M; Farah, S [Atomic Energy Commission, Dept. of Agriculture, Damascus (Syrian Arab Republic)

1998-02-01

Despite the increased production of strawberry in Syria, the storability and marketability of fruits were not well studied. The objectives of this study were to investigate the effect of gamma irradiation on storability of Senga sengana strawberry produced in Syria and the effect of gamma irradiation on fungal sp. i.e. Botrytis; Penicillium; Rhizopus. The fruits were treated with 1 , 2 and 3 KGy of gamma rays. Treated and untreated fruits were stored at 2 to 4 centigrade and 80 to 90 % relative humidity (RH). In order to investigate their marketability, the fruits where held at room temperature (25 to 30 centigrade). Weight loss, microbial decay, and total loss, juice production, pH, total soluble solids of the juice and organoleptic qualities were evaluated throughout the different storage and marketing periods. The results indicate that gamma irradiation decreased the microbial decay and increased the storability and marketability of fruits by 50 and 100% after using 2 and 3 kGy, respectively. D10 were 1.8 and 2.4 for Botrytis and Rhizopus respectively. One day after irradiation total soluble solids and its pH values were increased. Fourteen days later, irradiated fruits produced more juice with higher pH, but total soluble solids were less. Gamma irradiation did not have an effect on aroma and colour of fruits, whereas, 3 kGy of gamma irradiation had an adverse negative effect on taste. (author)

Results on Neutron and Gamma Irradiation of Electrolytic Tilmeters

Energy Technology Data Exchange (ETDEWEB)

Calderon, A.; Calvo, E.; Figueroa, C. F.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Vila, I.; Virto, A. L.; Alberdi, J.; Arce, P.; Barcala, J. M.; Fernando, A.; Fuentes, J.; Josa, M. I.; Luque, J. M.; Molinero, A.; Navarrate, J.; Valdivieso, P.; Fenyvesi, A.; Molnar, J.

2004-07-01

We report on irradiation studies done to a sample of high precision electrolytic tiltmeters with gamma-rays, up to a maximum dose of 150 kGy, an neutrons, up to a maximum fluence 1.5x10''14 cm''2. The effect of the irradiation on their performance is discussed. (Author) 19 refs.

Effects of gamma-ray irradiation on optical properties of ZnO-PbO-B2O3 glasses

DEFF Research Database (Denmark)

Sharma, G.; Thind, K.S.; Manupriya, -

2006-01-01

Effects of gamma-ray irradiation on some optical properties of xZnO(.)2xPbO(.)(1-3x)B2O3 glasses have been studied in the wavelength range 300-800 nm. Decrease in transmittance indicates the formation of color-center defects. Values for the energy-band gap, the width of the energy tail above...... the mobility gap and the cut-off wavelength have been measured before and after irradiation. Changes in the optical properties are explained in terms of radiation-induced structural defects and the composition of the glass....

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

International Nuclear Information System (INIS)

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

1996-03-01

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

Influence of irradiation conditions on the gamma irradiation effect in polyethylene

International Nuclear Information System (INIS)

Kacarevic-Popovic, Z.; Gal, O.; Novakovic, L.J.; Secerov, B.

2002-01-01

Complete text of publication follows. The radiation cross-linking of polyethylene, due to its high cross-linking yield, has resulted in the radiation technology that has found application in radiation production of heat shrinkable structures and in improvement of mechanical and thermo-physical properties of oriented polyethylene objects. It is observed that the cross-linking efficiency decreases when the irradiation is carried out in the presence of oxygen. In order to estimate the conditions that improve cross-linking efficiency, gamma irradiation effect in two types of polyethylene, irradiated in water and air was investigated. The polyethylene samples used were the low density (LDPE) Lotrene CdF 0302 with 45% crystallinity and the high density (HDPE) Hiplex EHM 6003 with 73% crystallinity. Both kinds of samples, fixed in the Pyrex glass tubes, were simultaneously irradiated with 60 Co gamma rays in distilled water and air, at a doses rate of 9,5 kGy/h (determined by the Fricke dosimeter) at room temperature. Radiation induced oxidative degradation was followed through oxygen containing group formation by the carbonyl group band (1720 cm -1 ) and transvinylene group formation by the band at 966 cm -1 in the infrared spectra. Cross-linking efficiency was determined by gel content using the procedure of the extraction in xylene. The monitored effects of gamma irradiation in water and air point to the conclusion that irradiation in water leads to the lower oxidative degradation and higher cross-linking compared with the effects measured after irradiation in air

Modifications induced by gamma irradiation to Makrofol polymer nuclear track detector

Directory of Open Access Journals (Sweden)

A. Tayel

2015-03-01

Full Text Available The aim of the present study was extended from obtaining information about the interaction of gamma rays with Makrofol DE 7-2 track detector to introduce the basis that can be used in concerning simple sensor for gamma irradiation and bio-engineering applications. Makrofol polymer samples were irradiated with 1.25 MeV 60Co gamma radiations at doses ranging from 20 to 1000 kG y. The modifications of irradiated samples so induced were analyzed using UV–vis spectrometry, photoluminescence spectroscopy, and the measurements of Vickers’ hardness. Moreover, the change in wettability of irradiated Makrofol was investigated by the contact angle determination of the distilled water. UV–vis spectroscopy shows a noticeable decrease in the energy band gap due to gamma irradiation. This decrease could be attributed to the appearance of a shift to UV spectra toward higher wavelength region after irradiation. Photoluminescence spectra reveal a remarkable change in the integrated photoluminescence intensity with increasing gamma doses, which may be resulted from some matrix disorder through the creation of some defected states in the irradiated polymer. The hardness was found to increase from 4.78 MPa for the unirradiated sample to 23.67 MPa for the highest gamma dose. The contact angle investigations show that the wettability of the modified samples increases with increasing the gamma doses. The result obtained from present investigation furnishes evidence that the gamma irradiations are a successful technique to modify the Makrofol DE 7-2 polymer properties to use it in suitable applications.

Dose mapping simulation using the MCNP code for the Syrian gamma irradiation facility and benchmarking

International Nuclear Information System (INIS)

Khattab, K.; Boush, M.; Alkassiri, H.

2013-01-01

Highlights: • The MCNP4C was used to calculate the gamma ray dose rate spatial distribution in for the SGIF. • Measurement of the gamma ray dose rate spatial distribution using the Chlorobenzene dosimeter was conducted as well. • Good agreements were noticed between the calculated and measured results. • The maximum relative differences were less than 7%, 4% and 4% in the x, y and z directions respectively. - Abstract: A three dimensional model for the Syrian gamma irradiation facility (SGIF) is developed in this paper to calculate the gamma ray dose rate spatial distribution in the irradiation room at the 60 Co source board using the MCNP-4C code. Measurement of the gamma ray dose rate spatial distribution using the Chlorobenzene dosimeter is conducted as well to compare the calculated and measured results. Good agreements are noticed between the calculated and measured results with maximum relative differences less than 7%, 4% and 4% in the x, y and z directions respectively. This agreement indicates that the established model is an accurate representation of the SGIF and can be used in the future to make the calculation design for a new irradiation facility

Effects of low dose gamma-ray radiation on the seed germination and physiological activity of vegetable crops

Energy Technology Data Exchange (ETDEWEB)

Kim, J. S.; Baek, M. H.; Lee, Y. G. [KAERI, Taejon (Korea, Republic of); Jung, K. H. [Kyunghee Univ., Yongin (Korea, Republic of)

2000-10-01

To determine the effect of low dose gamma-ray radiation on the germination rate and physiology of germinative seeds of Chinese cabbage(Brassica campestris L. cv. Hanyoreum) and radish(Raphanus sativus L. cv. Chungsukoungzoung). The germination rate of irradiation group was higher than that of the control. Especially it was highest at the early stage of induction. The germination rate of Chinese cabbage increased at 4 Gy-, 10 Gy- and 50 Gy irradiation group and that of radish increased at 2 Gy-, 6 Gy- and 10 Gy irradiation group. The seedling height of Chinese cabbage and radish increased positively in low dose irradiation group. The seedling height of Chinese cabbage was noticeably higher at 4 Gy and 10 Gy irradiation group and that of radish at 6 Gy irradiation group. The protein contents of seeds irradiated with low dose gamma-ray radiation was increased compared to that of the control especially at the early stage of induction. The enzyme activity of seeds irradiated with low dose of gamma-ray radiation was increased at 4 Gy and 10 Gy irradiation group. These results suggest that the germination and physiological activity of old seeds could be stimulated promisingly by the low dose gamma-ray radiation.

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

Role of NADP+-dependent isocitrate dehydrogenase (NADP+-ICDH) on cellular defence against oxidative injury by gamma-rays.

Science.gov (United States)

Lee, S H; Jo, S H; Lee, S M; Koh, H J; Song, H; Park, J W; Lee, W H; Huh, T L

2004-09-01

To investigate the regulation of NADPH-producing isocitrate dehydrogenase (ICDH) in cytosol (IDPc) and mitochondria (IDPm) upon gamma-ray irradiation, and the roles of IDPc and IDPm in the protection against cellular damage induced by gamma-ray irradiation. Changes of IDPc and IDPm proteins upon gamma-ray irradiation to NIH3T3 cells were analysed by immunoblotting. To increase or decrease the expression of IDPc or IDPm, NIH3T3 cells were stably transfected with mouse IDPc or IDPm cDNA in either the sense or the antisense direction. The transfected cells with either increased or decreased IDPc or IDPm were exposed to gamma-rays, and the levels of reactive oxygen species generation, protein oxidation and lipid peroxidation were measured. Both IDPc and IDPm activities were induced by gamma-ray in NIH3T3 cells. Cells with decreased expression of IDPc or IDPm had elevated reactive oxygen species generation, lipid peroxidation and protein oxidation. Conversely, overproduction of IDPc or IDPm protein partially protected the cells from oxidative damage induced by gamma-ray irradiation. The protective role of IDPc and IDPm against gamma-ray-induced cellular damage can be attributed to elevated NADPH, reducing equivalents needed for recycling reduced glutathione in the cytosol and mitochondria. Thus, a primary biological function of the ICDHs may be production of NADPH, which is a prerequisite for some cellular defence systems against oxidative damage.

Gamma irradiation influence on physical properties of milk proteins

International Nuclear Information System (INIS)

Ciesla, K.; Salmieri, S.; Lacroix, M.; Le Tien, C.

2004-01-01

Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and β-sheets, in particular from increase of β-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling

Gamma irradiation influence on physical properties of milk proteins

Energy Technology Data Exchange (ETDEWEB)

Ciesla, K. E-mail: kciesla@orange.ichtj.waw.pl; Salmieri, S.; Lacroix, M.; Le Tien, C

2004-10-01

Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and {beta}-sheets, in particular from increase of {beta}-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling.

Impacts of gate bias and its variation on gamma-ray irradiation resistance of SiC MOSFETs

Energy Technology Data Exchange (ETDEWEB)

Murata, Koichi; Mitomo, Satoshi; Matsuda, Takuma; Yokoseki, Takashi [Saitama University, Sakuraku (Japan); National Institutes for Quantum and Radiological Science and Technology (QST), Takasaki (Japan); Makino, Takahiro; Onoda, Shinobu; Takeyama, Akinori; Ohshima, Takeshi [National Institutes for Quantum and Radiological Science and Technology (QST), Takasaki (Japan); Okubo, Shuichi; Tanaka, Yuki; Kandori, Mikio; Yoshie, Toru [Sanken Electric Co., Ltd., Niiza, Saitama (Japan); Hijikata, Yasuto [Saitama University, Sakuraku (Japan)

2017-04-15

Gamma-ray irradiation into vertical type n-channel hexagonal (4H)-silicon carbide (SiC) metal-oxide-semiconductor field effect transistors (MOSFETs) was performed under various gate biases. The threshold voltage for the MOSFETs irradiated with a constant positive gate bias showed a large negative shift, and the shift slightly recovered above 100 kGy. For MOSFETs with non- and a negative constant biases, no significant change in threshold voltage, V{sub th}, was observed up to 400 kGy. By changing the gate bias from positive bias to either negative or non-bias, the V{sub th} significantly recovered from the large negative voltage shift induced by 50 kGy irradiation with positive gate bias after only 10 kGy irradiation with either negative or zero bias. It indicates that the positive charges generated in the gate oxide near the oxide-SiC interface due to irradiation were removed or recombined instantly by the irradiation under zero or negative biases. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Elimination of N-nitrosamines and their precusors in some foods by /sup 60/Co. gamma. -ray irradiation

Energy Technology Data Exchange (ETDEWEB)

Jifan, Hu; Yingqiang, He; Puju, Song

1987-10-01

N-Dimethylnitrosamine (NDMA) in some marine foods, such as dried shrimp, fish meal and salted fish, was drastically reduced by ..gamma..-ray irradiation with /sup 60/Co. The shrimp contained 54.6 ppb NDMA, but only 29.3, 8.8, 11.4, and 1.9 ppb were detected after irradiation with doses of 5, 10, 15 and 20 kGy. The corresponding reduction was 46.3%, 83.9%, 79.1%, and 96.6%, respectively. Similar results were also obtained in other two kinds of foods. NDMA could be completely eliminated by the irradiation in aqueous solution, which was much more markable than that in food samples. The major irradiated products of NDMA were dimethylamine and nitrous acid, but no re-formation of nitrosamines took place. /sup 60/Co irradiation also significantly decreased the content of nitrite in salted fish and in aqueous solution. No effect on nitrate could be observed.

The effect of pre-heating and pre-irradiation with gamma rays on thermal annealing in bis [n-benzoil-n-phenyl hydroxilaminate] copper (II)

International Nuclear Information System (INIS)

Nakanishi, C.; Silva, C.P.G. da.

1988-10-01

The main purpose of this work was to make a contribution to the study of the chemical effects of the (n,γ) reaction on copper chelate. The influence of some factors such as pre-heating and pre-irradiation with gamma-rays on the retention and thermal annealing of bis-[N-benzoil-N-phenlhydroxilaminate] copper (II) was investigated. The complex was synthesized and later characterized by means of: determination of the melting-Point, elemental analysis, infra-red and vesible range absortion spectrophotometry. The compound was heated and also irradiated with gamma-rays in order to verify the effect of thermolysis and radiolysis on the retention. It seems that heat gamma-radiation can produce deffects which will lower the susceptibility of the compound to thermal annealing. On the model envolving electronic species some explanation of ours results were made and a mechanism was proposed for the retention and thermal annealing aasuming the capture of free electrons and also the existence of holes. (author) [pt

Gamma irradiation effect on the chemical composition and the antioxidant activity of Ipomoea batatas L

Energy Technology Data Exchange (ETDEWEB)

Tahir, D., E-mail: dtahir@fmipa.unhas.ac.id; Halide, H., E-mail: dtahir@fmipa.unhas.ac.id; Kurniawan, D. [Department of Physics, Hasanuddin University, Makassar 90245 (Indonesia); Wahab, A. W. [Department of Chemistry, Hasanuddin University, Makassar 90245 (Indonesia)

2014-09-25

The chemical composition and antioxidant activity of Ipomoea batatas L. (sweet potato) were studied by x-ray fluorescence (XRF) spectroscopy, Fourier transform infrared spectroscopy, and by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity. The irradiation treatment was performed by using Cs-137 as a gamma sources in experimental equipment. Treatment by irradiation emerges as a possible conservation technique that has been tested successfully in several food products. The amount of chemical composition was changed and resulting new chemical for absorbed dose 40 mSv. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by DPPH radical scavenging capacity. The antioxidant activity of Ipomoea batatas L. extract was dramatically increased in the non-irradiated sample to the sample irradiated at 40 mSv. These results indicate that gamma irradiation of Ipomoea batatas L. extract can enhance its antioxidant activity through the formation of a new chemical compound. Based on these results, increased antioxidant activity of Ipomoea batatas L. extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.

Nutritional balance of pigs irradiated on the hind part with 1100 rd of 60Co gamma rays

International Nuclear Information System (INIS)

Daburon, F.; Tricaud, Y.; Bourhoven, D.; Marion, C.

1978-01-01

The hind part of 10 adult miniature pigs was irradiated with 1100 rd of 60 Co gamma rays. The dietary mineral (Na, K, Ca, P), nitrogen and lipid balances of the animals were studied before and 1, 3 and 5 months after irradiation. While the classical early lesion of the intestinal mucosa recovered quite satisfactorily within one or two months, a pancreatic atrophy process developed progressively which might play a major role in the nutritional state of the pigs and thus in their survival. Concerning nutritional balance, nitrogen and sodium retention were perturbed until 5 months post-irradiation; cyanocobalamin absorption remained very low. Dry and organic matter utilization recovered nearly normal values in the 3rd ou 5th month [fr

Effect of gamma-irradiation on biodegradable microspheres loaded with rasagiline mesylate

International Nuclear Information System (INIS)

Fernandez, Marcos; Barcia, Emilia; Negro, Sofia

2016-01-01

In the present study, the influence of gamma-irradiation was evaluated on the physicochemical characteristics and in vitro release of rasagiline mesylate (RM), a selective MAO-B inhibitor used in Parkinson's disease, from poly(D,L-lactide-co-glycolide) (PLGA) microspheres. Microspheres were prepared using PLGA 50:50 by the solvent evaporation technique (O/W emulsion). Microspheres were sterilized by gamma-irradiation and their influence was assessed by scanning electron microscopy (SEM), laser light diffraction, differential scanning calorimetry (DSC), X-ray diffraction (XRD), gel permeation chromatography (GPC), encapsulation efficiency (EE) and in vitro drug release. Gamma-irradiation of RM-loaded microspheres did not affect EE, DSC and XRD patterns. After gamma-irradiation, changes on the surface were observed by SEM, but no significant difference in mean particle size was observed. GPC measurements showed a decrease in molecular weight of the polymer after five days of in vitro release. The similarity factor value between irradiated and non-irradiates microspheres was <50, indicating the non-similarity of the release profiles. The sterilization technique had an effect on the integrity of polymeric system, significantly affecting in vitro release of RM from PLGA microspheres. Therefore, from our results we conclude that gamma-irradiation is not a suitable sterilization procedure for this formulation

Inactivation of RNA viruses by gamma irradiation

International Nuclear Information System (INIS)

Nonomiya, Takashi; Morimoto, Akinori; Iwatsuki, Kazuo; Tsutsumi, Takamasa; Ito, Hitoshi; Yamashiro, Tomio; Ishigaki, Isao.

1992-01-01

Four kinds of RNA viruses, Bluetongue virus (BT), Bovine Virus Diarrhea-Mucosal Disease virus (BVD·MD), Bovine Respiratory Syncytial virus (RS), Vesicular Stmatitis virus (VS), were subjected to various doses of gamma irradiation to determine the lethal doses. The D 10 values, which are the dose necessary to decimally reduce infectivity, ranged from 1.5 to 3.4 kGy under frozen condition at dry-ice temperature, and they increased to 2.6 to 5.0 kGy under frozen condition at dry-ice temperature. Serum neutralzing antibody titer of Infectious Bovine Rhinotracheitis (IBR) was not adversely changed by the exposure to 36 kGy of gamma-rays under frozen condition. Analysis of electrophoresis patterns of the bovine serum also reveales that the serum proteins were not remarkably affected, even when exposed to 36 kGy of gamma radiation under frozen condition. The results suggested that gamma irradiation under frozen condition is an effective means for inactivating both DNA and RNA viruses without adversely affecting serum proteins and neutralizing antibody titer. (author)

Inactivation of RNA viruses by gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Nonomiya, Takashi; Morimoto, Akinori; Iwatsuki, Kazuo; Tsutsumi, Takamasa (Ministry of Agriculture, Forestry and fisheries, Yokohama, Kanagawa (Japan). Animal Quarantine Service); Ito, Hitoshi; Yamashiro, Tomio; Ishigaki, Isao

1992-09-01

Four kinds of RNA viruses, Bluetongue virus (BT), Bovine Virus Diarrhea-Mucosal Disease virus (BVD[center dot]MD), Bovine Respiratory Syncytial virus (RS), Vesicular Stmatitis virus (VS), were subjected to various doses of gamma irradiation to determine the lethal doses. The D[sub 10] values, which are the dose necessary to decimally reduce infectivity, ranged from 1.5 to 3.4 kGy under frozen condition at dry-ice temperature, and they increased to 2.6 to 5.0 kGy under frozen condition at dry-ice temperature. Serum neutralzing antibody titer of Infectious Bovine Rhinotracheitis (IBR) was not adversely changed by the exposure to 36 kGy of gamma-rays under frozen condition. Analysis of electrophoresis patterns of the bovine serum also reveales that the serum proteins were not remarkably affected, even when exposed to 36 kGy of gamma radiation under frozen condition. The results suggested that gamma irradiation under frozen condition is an effective means for inactivating both DNA and RNA viruses without adversely affecting serum proteins and neutralizing antibody titer. (author).

TL detectors for gamma ray dose measurements in criticality accidents

International Nuclear Information System (INIS)

Miljanic, S.; Zorko, B.; Gregori, B.; Knezevic, Z.

2007-01-01

Determination of gamma ray dose in mixed neutron + gamma ray fields is still a demanding task. Dosemeters used for gamma ray dosimetry are usually in some extent sensitive to neutrons and their response variations depend on neutron energy i.e., on neutron spectra. Besides, it is necessary to take into account the energy dependence of dosemeter responses to gamma rays. In this work, several types of thermoluminescent detectors (TLD) placed in different holders used for gamma ray dose determination in the mixed fields were examined. Dosemeters were from three different institutions: Ruder Boskovic Inst. (RBI), Croatia, Jozef Stefan Inst. (JSI), Slovenia and Autoridad Regulatoria Nuclear (ARN), Argentina. All dosemeters were irradiated during the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, June 2002. Three accidental scenarios were reproduced and in each irradiation the dosemeters were exposed placed on the front of phantom and 'free in air'. Following types of TLDs were used: 7 LiF (TLD-700), CaF 2 :Mn and Al2 O3 :Mg,Y - all from RBI; CaF 2 :Mn from JSI and 7 LiF (TLD-700) from ARN. Reported doses were compared with the reference values as well as with the values obtained from the results of all participants. The results show satisfactory agreement with other dosimetry systems used in the Intercomparison. The influence of different types of holders and applied corrections of dosemeters' readings are discussed. (authors)

TL detectors for gamma ray dose measurements in criticality accidents.

Science.gov (United States)

Miljanić, Saveta; Zorko, Benjamin; Gregori, Beatriz; Knezević, Zeljka

2007-01-01

Determination of gamma ray dose in mixed neutron+gamma ray fields is still a demanding task. Dosemeters used for gamma ray dosimetry are usually in some extent sensitive to neutrons and their response variations depend on neutron energy i.e., on neutron spectra. Besides, it is necessary to take into account the energy dependence of dosemeter responses to gamma rays. In this work, several types of thermoluminescent detectors (TLD) placed in different holders used for gamma ray dose determination in the mixed fields were examined. Dosemeters were from three different institutions: Ruder Bosković Institute (RBI), Croatia, JoZef Stefan Institute (JSI), Slovenia and Autoridad Regulatoria Nuclear (ARN), Argentina. All dosemeters were irradiated during the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, June 2002. Three accidental scenarios were reproduced and in each irradiation the dosemeters were exposed placed on the front of phantom and 'free in air'. Following types of TLDs were used: 7LiF (TLD-700), CaF2:Mn and Al2O3:Mg,Y-all from RBI; CaF2:Mn from JSI and 7LiF (TLD-700) from ARN. Reported doses were compared with the reference values as well as with the values obtained from the results of all participants. The results show satisfactory agreement with other dosimetry systems used in the Intercomparison. The influence of different types of holders and applied corrections of dosemeters' readings are discussed.

Observations of the highest energy gamma-rays from gamma-ray bursts

International Nuclear Information System (INIS)

Dingus, Brenda L.

2001-01-01

EGRET has extended the highest energy observations of gamma-ray bursts to GeV gamma rays. Such high energies imply the fireball that is radiating the gamma-rays has a bulk Lorentz factor of several hundred. However, EGRET only detected a few gamma-ray bursts. GLAST will likely detect several hundred bursts and may extend the maximum energy to a few 100 GeV. Meanwhile new ground based detectors with sensitivity to gamma-ray bursts are beginning operation, and one recently reported evidence for TeV emission from a burst

Chromosomal rearrangements caused by gamma-irradiation in winter wheat cells

Directory of Open Access Journals (Sweden)

M. M. Nazarenko

2017-02-01

Full Text Available In this article we report the results of our investigation into several cytogenetic parameters of variability in mutation induction of modern winter wheat varieties and some connections between the means of cytogenetic indices and different doses of gamma-rays. Analysis of chromosomal aberrations following the action of any kind of mutagen by the anaphases method is one of the most widely investigated and most precise methods which can be used to determine the fact of mutagenic action on plants and identify the nature of the mutagen. We combined in our investigation the sensitivity of genotype to mutagen using cytological analysis of mutagen treated wheat populations with the corresponding different varieties by breeding methods to reveal its connections and differences, specific sensitivity to mutagens action on the cell level. Dry seeds of 8 varieties of winter wheat were subjected to 100, 150, 200, 250 Gy gamma irradiation, which are trivial for winter wheat mutation breeding. We investigated rates and spectra of chromosomal aberrations in the cells of winter wheat primary roots tips. The coefficients of correlations amid the rate of chromosomal aberrations and the dose of gamma-rays were on the level 0.8–0.9. The fragments/bridges ratio is a clear and sufficient index for determining the nature of the mutagen agent. We distinguished the following types of chromosomal rearrangements: chromatid and chromosome bridges, single and double fragments, micronuclei, and delayed chromosomes. The ratio of chromosomal aberrations changes with the change in mutagen; note that bridge-types are characteristic of irradiation. Radiomutants are more resistant to gamma rays. This is apparent in the lower rate of chromosomal aberrations. Varieties obtained by chemical mutagenesis (varieties Sonechko, Kalinova are more sensitive to gamma-irradiation than others. We propose these varieties as objects for a mutation breeding programme and radiation of mutants

Effects of Gamma Irradiation on Polyvinylidene Fluoride Thin Films

Science.gov (United States)

Madivalappa, Shivaraj; Jali, V. M.

2018-02-01

Polyvinylidene fluoride thin films were synthesized by Sol-Gel method with spin rate of 3000 rpm for 30 sec on ITO glass substrates and were annealed at 170 C. The films were irradiated by Gamma radiation with different doses (10, 30, 40 and 50 kGy). XRD and FTIR spectra have been obtained to identify the presence of α / β phases. Mean crystallite size was calculated by Scherer’s equation. Different vibrational bands were identified and percentage of β phase was determined by FTIR analysis. Optical properties like band gap, refractive index, optical activation energy have been determined. Surface morphology and compositions of pristine and gamma irradiated PVDF thin films were confirmed respectively, by SEM and Energy dispersive X-ray analysis. The comparison of the structural and optical optical properties of pristine PVDF polymer film has been made with those of the Gamma irradiated films.

Design of a {gamma}-ray analysis system for determination of boron in a patient`s head, during neutron irradiation

Energy Technology Data Exchange (ETDEWEB)

Verbakel, W.F.A.R.

1997-12-01

Boron Neutron Capture Therapy (BNCT) is a new radiation therapy in which thermal neutron capture by {sup 10}B is used for the selective destruction of a cancer tumour. At the High Flux Reactor (HFR) in Petten, Netherlands, a therapy facility is built for the neutron irradiations. In first instance, patients with a brain tumour will be treated. The doses delivered to the tumour and to the healthy tissue depend on the thermal neutron fluence and on the boron concentrations in these regions. Yet, both concentrations change in time after the administration of the tumour-seeking boron compound. An accurate determination of the patient`s dose requires the knowledge of these time dependent concentrations during the therapy. For this reason, a {gamma}-ray telescope system, together with a reconstruction tool, are developed. Two HPGe-detectors measure the 478 keV prompt {gamma}-rays which are emitted at the boron neutron capture reaction, in a large background of {gamma}-rays and neutrons. By using the detectors in a telescope configuration, only {gamma}-rays emitted by a small specific region are detected. The best shielding of the detectors is obtained by performing the measurements through a small hole in the iron roof. A reconstruction tool is developed to calculate absolute boron concentrations using the measured boron {gamma}-ray detection rates. Besides the boron {gamma}-rays, a large component of 2.2 MeV {gamma}-rays emitted at thermal neutron capture in hydrogen is measured. Since the hydrogen distribution is almost homogeneous over the head, this component can serve as a measure of the total number of thermal neutrons in the observed volume. By using the hydrogen {gamma}-line for normalisation of the boron concentration, the reconstruction tool eliminates the greater part of the influence of the inhomogeneity of the thermal neutron distribution. MCNP calculations are used as a tool for the optimisation of the detector configuration. Experiments on a head phantom

Study of irradiated bothropstoxin-1 with 60Co gamma rays: immune system behavior

International Nuclear Information System (INIS)

Caproni, P.; Baptista, J.A.; Almeida, T.L. de; Nascimento, N.; Passos, L.A.C.

2009-01-01

Ionizing radiation has been successfully employed to modify the immunological properties of biomolecules. Very promising results were obtained when crude animal venoms, as well as isolated toxins, were treated with 60Co gamma rays, yielding toxoids with good immunogenicity. The achievement of modified antigens with lower toxicity and preserved or improved immunogenicity can be very useful. Ionizing radiation has already been proven to be a powerful tool to attenuate snake venom toxicity without affecting, and even increasing, their immunogenic properties. However, little is known about the modifications that irradiated molecules undergo and even less about the immunological response that such antigens elicit. In the present work, we investigated the immunological behavior of bothropstoxin-1, a K49 phospholipase, before and after irradiation. Structural modifications of the toxin were analyzed by SDS-PAGE. Isogenic mice were immunized with either the native or the irradiated toxin. The circulating antibodies were isotyped and titrated by ELISA. According to our data, irradiation promoted structural modifications in the toxin characterized by higher molecular weight forms of proteins (aggregates and oligomers). The results also indicated that irradiated toxins were immunogenic and antibodies elicited by them were able to recognize the native toxin in ELISA. These findings suggest that irradiation of toxic proteins can promote significant modifications in their structures; however they still retain many of the original antigenic and immunological properties of native proteins. Also, our data indicate that irradiated proteins induce higher titers of IgG2a and IgG2b, suggesting that Th1 cells are predominantly involved in the immune response. (author)

Characterization of injected linear low density polyethylene (LLDPE) irradiated by gamma-ray

International Nuclear Information System (INIS)

Oliveira, Ana C.F.; Parra, Duclerc F.; Ferreto, Helio F.R.; Lugao, Ademar B.

2013-01-01

The aim of this paper is to investigate of gamma irradiation effects on linear low density polyethylene (LLDPE) injected. Polymers processed by gamma radiation have new physical-chemical and mechanical properties. The ionizing radiation promotes chain scission and creates free radicals which can recombine, providing their annihilation, for crosslinking or branching. The polymer was irradiated with a source of 60 Co at doses of 5, 10, 20, 50 or 100 kGy at about 5 kGy s -1 rate, at room temperature. The changes in molecular structure of LLDPE were evaluated using melt flow index, gel fraction, differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FT-IR) and thermogravimetry analysis (TG). The results showed that the properties depend on dose irradiation. (author)

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

International Nuclear Information System (INIS)

Hayashi, Toru; Todoriki, Setsuko; Mamun.

1993-01-01

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

Comparative study of neutron and gamma-ray pulse shape discrimination of anthracene, stilbene, and p-terphenyl

International Nuclear Information System (INIS)

Yanagida, Takayuki; Watanabe, Kenichi; Fujimoto, Yutaka

2015-01-01

Solid state organic scintillators, such as anthracene, stilbene, and p-terphenyl were investigated on their basic scintillation properties and neutron–gamma discrimination capabilities. Scintillation wavelengths under X-ray irradiation of anthracene, stilbene, and p-terphenyl were 445–525, 400–500, and 350–450 nm, respectively. Scintillation light yields of anthracene, stilbene, and p-terphenyl under 137 Cs gamma-ray irradiation were 20100, 16000, and 19400 ph/MeV, respectively. Neutron and gamma-ray events discrimination capabilities were examined and anthracene exhibited the best figure of merit among three organic scintillators

Comparative study of neutron and gamma-ray pulse shape discrimination of anthracene, stilbene, and p-terphenyl

Energy Technology Data Exchange (ETDEWEB)

Yanagida, Takayuki, E-mail: yanagida@lsse.kyutech.ac.jp [Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu, Kitakyushu, Fukuoka 808-0196 (Japan); Watanabe, Kenichi [Nagoya University, Furocho, Chikusa, Nagoya 464-8603 (Japan); Fujimoto, Yutaka [Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu, Kitakyushu, Fukuoka 808-0196 (Japan)

2015-06-01

Solid state organic scintillators, such as anthracene, stilbene, and p-terphenyl were investigated on their basic scintillation properties and neutron–gamma discrimination capabilities. Scintillation wavelengths under X-ray irradiation of anthracene, stilbene, and p-terphenyl were 445–525, 400–500, and 350–450 nm, respectively. Scintillation light yields of anthracene, stilbene, and p-terphenyl under {sup 137}Cs gamma-ray irradiation were 20100, 16000, and 19400 ph/MeV, respectively. Neutron and gamma-ray events discrimination capabilities were examined and anthracene exhibited the best figure of merit among three organic scintillators.

Effectiveness of gamma ray irradiation and ethyl methane ...

African Journals Online (AJOL)

채소실험실

2013-07-24

Jul 24, 2013 ... Department of Plant Science, Gangneung-Wonju National University, ... DNKW001 were discovered sturdy plants with thicker leaf and bigger pollen than octoploid plant, while ... Application of mutagen was intended to increase gene- ..... Effects of gamma ray and EMS treatment on the survival rate of ...

Effect of Gamma Rays on Fast Neutron Registration in CR-39

CERN Document Server

Kobzev, A P; El-Halem, A A; Abdul-Ghaphar, U S; Salama, T A

2002-01-01

A set of CR-39 plastic detectors with front PE radiator was exposed to Am-Be neutron source, which has an emission rate of 0.86\\cdot 10^{7} sec^{-1}, and the neutron dose equivalent rate 1 m apart from the source is equal to 11 mrem/hr. Another set of samples was irradiated by a neutron dose of 4 rem, then exposed to different gamma-ray doses using ^{60}Co source. It was found that the track density grows with the increase of neutron dose and etching time. It was also found that the bulk etching rate V_{B}, the track diameter and the sensitivity of the CR-39 plastic detector with respect to the neutron irradiation increased with increasing gamma-ray dose in the range 1?10 Mrad. These results show that CR-39 can be considered as a promising fast neutron dosimeter and gamma-ray dosimeter.

Meiotic chromosome behaviours in M1 generation of bread wheat irradiated by gamma-rays

International Nuclear Information System (INIS)

Watanabe, Y.; Takato, S.

1982-01-01

Growing plants of bread wheat (Triticum aestivum L. 2 n=6x=42, AABBDD) were subjected to acute or chronic irradiation by gamma-rays from 60Co and meiotic chromosome behaviours of PMCS in M 1 generation were cytologically compared. Both acute and chronic irradiations produced different types of chromosomal aberrations at the meiotic stages. Among them, translocation type was the most frequent, followed by univalent type. A mixed type, i. e. translocation accompanying one or more univalents was often detected. Even normal type which lacked translocation and univalent included laggards and briclges without exception. Other meiotic abnormalities such as deletion, iso-chromosome and micronuclei were observed frequently in both treatments. Dose dependency of translocation frequency was not recognized in this experiment. In chronic irradiation, different chromosome numbers and meiotic behaviours were found not only among florets of a spike but also among anthers of a floret. A number of plants with aneuploid-like grass types occurred at a high frequency in M 1 , especially with low exposure

DNA repair in modeled microgravity: Double strand break rejoining activity in human lymphocytes irradiated with {gamma}-rays

Energy Technology Data Exchange (ETDEWEB)

Mognato, Maddalena, E-mail: maddalena.mognato@unipd.it [Dipartimento di Biologia, Universita di Padova, via U. Bassi 58 B, 35121 Padova (Italy); Girardi, Cristina; Fabris, Sonia [Dipartimento di Biologia, Universita di Padova, via U. Bassi 58 B, 35121 Padova (Italy); Celotti, Lucia [Dipartimento di Biologia, Universita di Padova, via U. Bassi 58 B, 35121 Padova (Italy); Laboratori Nazionali di Legnaro, INFN, Padova (Italy)

2009-04-26

Cell response to ionising radiation depends, besides on genetic and physiological features of the biological systems, on environmental conditions occurring during DNA repair. Many data showed that microgravity, experienced by astronauts during space flights or modeled on Earth, causes apoptosis, cytoskeletal alteration, cell growth inhibition, increased frequency of mutations and chromosome aberrations. In this study, we analysed the progression of the rejoining of double strand breaks (DSBs) in human peripheral blood lymphocytes (PBLs) irradiated with {gamma}-rays and incubated in static condition (1g) or in modeled microgravity (MMG). {gamma}-H2AX foci formation and disappearance, monitored during the repair incubation, showed that the kinetics of DSBs rejoining was different in the two gravity conditions. The fraction of foci-positive cells decreased slower in MMG than in 1g at 6 and 24 h after irradiation (P < 0.01) and the mean number of {gamma}-H2AX foci per nucleus was significantly higher in MMG than in 1g at the same time-points (P < 0.001). In the same samples we determined apoptotic level and the rate of DSB rejoining during post-irradiation incubation. A significant induction of apoptosis was observed in MMG at 24 h after irradiation (P < 0.001), whereas at shorter times the level of apoptosis was slightly higher in MMG respect to 1g. In accordance with the kinetics of {gamma}-H2AX foci, the slower rejoining of radiation-induced DSBs in MMG was observed by DNA fragmentation analyses during the repair incubation; the data of pulsed-field gel electrophoresis assay showed that the fraction of DNA released in the gel was significantly higher in PBL incubated in MMG after irradiation with respect to cells maintained in 1g. Our results provide evidences that MMG incubation during DNA repair delayed the rate of radiation-induced DSB rejoining, and increased, as a consequence, the genotoxic effects of ionising radiation.

Egg weight and gamma-rays effects. Pt. 1

International Nuclear Information System (INIS)

Shebaita, M.K.; Ezzat, I.E.; Kamar, G.A.R.

1979-01-01

Two groups of egg weight from Egyptian Fayoumi breed were used in this study. The first group ranged in weight from 36-43 grams (group A) and the second group ranged from 44-50 grams (group B). Each egg weight group was divided to 6 exposure treatments to 60 Co gamma rays (non-irradiated, 150 rads, 300 rads, 450 rads, 600 rads and 750 rads). The data showed that embryonic mortality was 75% higher in irradiated treatments compared with the non-irradiated, and 50% of the mortality occurred during the first 5 days after the exposure. Moreover, mortality was 18% higher in group A than in group B. However, the abnormality was 6.4% in group A and 10.8% in group B. A delay in hatching time was observed and the hatching percent decreased due to the exposure to gamma rays. The relationship between hatching % (Y) and the dose level (X) was Y = 86.6 esup(-0.00041x) in group A and Y = 85.5 esup(-0.00028x) in group B. On the other hand, the hatching weight in irradiated treatments was higher (P [de

Degradation and annealing studies on gamma rays irradiated COTS PPD CISs at different dose rates

International Nuclear Information System (INIS)

Wang, Zujun; Ma, Yingwu; Liu, Jing; Xue, Yuan; He, Baoping; Yao, Zhibin; Huang, Shaoyan; Liu, Minbo; Sheng, Jiangkun

2016-01-01

The degradation and annealing studies on Colbalt-60 gamma-rays irradiated commercial-off-the-shelf (COTS) pinned photodiode (PPD) CMOS image sensors (CISs) at the various dose rates are presented. The irradiation experiments of COTS PPD CISs are carried out at 0.3, 3.0 and 30.0 rad(Si)/s. The COTS PPD CISs are manufactured using a standard 0.18-μm CMOS technology with four-transistor pixel PPD architecture. The behavior of the tested CISs shows a remarkable degradation after irradiation and differs in the dose rates. The dark current, dark signal non-uniformity (DSNU), random noise, saturation output, signal to noise ratio (SNR), and dynamic range (DR) versus the total ionizing dose (TID) at the various dose rates are investigated. The tendency of dark current, DSNU, and random noise increase and saturation output, SNR, and DR to decrease at 3.0 rad(Si)/s are far greater than those at 0.3 and 30.0 rad(Si)/s. The damage mechanisms caused by TID irradiation at the various dose rates are also analyzed. The annealing tests are carried out at room temperature with unbiased conditions after irradiation.

Degradation and annealing studies on gamma rays irradiated COTS PPD CISs at different dose rates

Science.gov (United States)

Wang, Zujun; Ma, Yingwu; Liu, Jing; Xue, Yuan; He, Baoping; Yao, Zhibin; Huang, Shaoyan; Liu, Minbo; Sheng, Jiangkun

2016-06-01

The degradation and annealing studies on Colbalt-60 gamma-rays irradiated commercial-off-the-shelf (COTS) pinned photodiode (PPD) CMOS image sensors (CISs) at the various dose rates are presented. The irradiation experiments of COTS PPD CISs are carried out at 0.3, 3.0 and 30.0 rad(Si)/s. The COTS PPD CISs are manufactured using a standard 0.18-μm CMOS technology with four-transistor pixel PPD architecture. The behavior of the tested CISs shows a remarkable degradation after irradiation and differs in the dose rates. The dark current, dark signal non-uniformity (DSNU), random noise, saturation output, signal to noise ratio (SNR), and dynamic range (DR) versus the total ionizing dose (TID) at the various dose rates are investigated. The tendency of dark current, DSNU, and random noise increase and saturation output, SNR, and DR to decrease at 3.0 rad(Si)/s are far greater than those at 0.3 and 30.0 rad(Si)/s. The damage mechanisms caused by TID irradiation at the various dose rates are also analyzed. The annealing tests are carried out at room temperature with unbiased conditions after irradiation.

Study on the changes in phyicochemical properties of seafood cooking drips by gamma ray irradiation

International Nuclear Information System (INIS)

Choi, Jong Il; Kim, Yeon Joo; Kim, Jae Hun; Yoon, Yo Han; Song, Beom Seok; Lee, Ju Woon; Chun, Byung Soo; Ahn, Dong Hyun; Lee, Ju Yeoun

2010-01-01

Cooking drips which were obtained as by-product after seafood processing in the food industries, still contain lots of proteins, carbohydrates, and other functional materials. But, the seafood cooking drips are easily contaminated because of its rich nutrients, and their color are very dark. This study was conducted to investigate the effect of gamma irradiation on the quality of seafood cooking drips including Hizikia fusiformis, Enteroctopus dofleini, and Thunnus thynnus. The Hunter's color values (L, Brightness) of H. fusiformis, and T.thynnus, were increased with increasing irradiation doses, showing becoming bright. The crude protein content and crude lipid content were increased by gamma irradiation. These results indicated that gamma irradiation increased extraction efficiency of available compounds in cooking drips

Gamma radiation sensitivity in tomato tree and response of plants proceeding from salinity irradiated seeds

International Nuclear Information System (INIS)

Colaco, Waldeciro; Bidjeke, Raoul; Fleming, Peter M.

2000-01-01

Preliminary experiments were conducted to evaluate the radiosensitivity of tomato {Lycopersicon esculentum L. cultivars IPA-6, IPA-8, and Lycopersicum hirsutum glabratum - } to gamma rays from a 60 Co source, considering future induced mutation studies aiming at the improvement of plant salinity tolerance. Sets of dry seeds were exposed to gamma radiation doses (300 - 600 Gy and 100-400 Gy) and compared to a control without irradiation (0 Gy) under greenhouse conditions. The radiosensitivity was initially evaluated through germination of irradiated dry seeds determined at 13 and 30 days after irradiation and also through seedling survival. Seed germination was delayed by gamma irradiation and especially reduced at higher doses (300- 600 Gy). Survival of tomato plants was decreased with increased dose of radiation and was reduced by < 16% at the 300-600 Gy doses. Growth of plants was enhanced at low doses of gamma rays; higher doses reduced plant size. Gamma irradiation had significant effects on tomato plants generated from dry seed and submitted to different levels of salinity. It is recommended a dose range of 100-200 Gy for mutation breeding purpose using the varieties tested. (author)

Cellular Stress to Low Gamma-ray Dose

International Nuclear Information System (INIS)

Manzanares-Acuna, E.; Vega-Carrillo, H. R.; Letechipia de Leon, C.; Guzman Enriquez, L. J.; Garcia-Talavera, M.

2004-01-01

The purpose of this study was to evaluate the effect of low gamma ray intensity upon Hsp 70 expression in human lymphocytes. the heat shock proteins (Hsp) family, are a group of proteins present in all living organism, therefore there are highly conserved and are related to adaptation and evolution. At cellular level these proteins acts as chaperones correcting denatured proteins. when a stress agent, such heavy metals, UV, heat, etc. is affecting a cell a response to this aggression is triggered through overexpression of Hsp. Several studies has been carried out in which the cellular effect are observed, mostly of these studies uses large doses, but very few studies are related with low doses. Blood of healthy volunteers was obtained and the lymphocytes were isolated by ficoll-histopaque gradient. Experimental lots were irradiated in a ''137Cs gamma-ray. Hsp70 expression was found since 0.5 cGy, indicating a threshold to very low doses of gamma rays. (Author) 27 refs

Comparison of X-ray and gamma-ray dose-response curves for pink somatic mutations in Tradescantia clone 02

International Nuclear Information System (INIS)

Underbrink, A.G.; Kellerer, A.M.; Mills, R.E.; Sparrow, A.H.; Brookhaven National Lab., Upton, N.Y.

1976-01-01

Microdosimetric data indicate that the mean specific energy, xi, produced by individual charged particles from X rays and gamma rays is different for the two radiation qualities by nearly a factor of two. In order to test whether this influences the initial, linear component in the dose-effect relations, a comparison was made between dose-response curves for pink somatic mutations in Tradescantia clone 02 stamen hairs following X and gamma irradiations. Absorbed doses ranged from 2.66 to 300 rad. The results are in agreement with predictions made on the basis of microdosimetric data. At low doses gamma rays are substantially less effective than X rays. The RBE of gamma rays vs. X rays at low doses was approximately 0.6, a value lower than those usually reported in other experimental systems. (orig.) [de

Characterization of modified PVDF membrane by gamma irradiation for non-potable water reuse.

Science.gov (United States)

Lim, Seung Joo; Kim, Tak-Hyun; Shin, In Hwan

2015-01-01

Poly(vinylidene fluorine) (PVDF) membranes were grafted by gamma-ray irradiation and were sulfonated by sodium sulfite to modify the surface of the membranes. The characteristics of the modified PVDF membranes were evaluated by the data of Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscope (FE-SEM), the contact angle of the membrane surface and the water permeability. From the results of FT-IR, XPS and FE-SEM, it was shown that the modified membranes were successfully grafted by gamma-ray irradiation and were sulfonated. The content of oxygen and sulfur increased with the monomer concentration, while the content of fluorine sharply decreased. The pore size of the modified membranes decreased after gamma-ray irradiation. The contact angle and the water permeability showed that the hydrophilicity of the modified membranes played a role in determining the membrane performance. The feasibility study of the modified PVDF membranes for using non-potable water reuse were carried out using a laboratory-scale microfiltration system. Grey wastewater was used as the influent in the filtration unit, and permeate quality satisfied non-potable water reuse guidelines in the Republic of Korea.

Kraft cooking of gamma irradiated wood, (1). Effect of alcohol additives on pre-irradiation

Energy Technology Data Exchange (ETDEWEB)

Inaba, M; Meshitsuka, G; Nakano, J [Tokyo Univ. (Japan). Faculty of Agriculture

1979-12-01

Studies have been made of kraft cooking of gamma irradiated wood. Beech (Fagus crenata Blume) wood meal suspended in aqueous alkaline alcohol was irradiated up to 1.5 KGy (0.15 Mrad) with gamma rays from a Co-60 source in the presence or absence of oxygen. The irradiated wood meals were washed thoroughly with fresh water, air dried and cooked under the ordinary cooking conditions. The results are summarized as follows: (1) Pre-irradiation in aqueous alkali have negligible effect on kraft cooking. (2) In the case of ethanol addition (50 g/l), pre-irradiation in vacuo shows acceleration of delignification and stabilization of carbohydrates during kraft cooking. Cooked yield gain by pre-irradiation was about 1.2 in all, over the range of delignification from 80 to 90%. Aqueous ethanol without alkali also shows positive but smaller effect than that with alkali. (3) Propanol, iso-propanol and butanol show positive but smaller effects than ethanol. However, methanol does not show any positive effect. (4) Irradiation in the presence of oxygen does not show any attractive effect on kraft cooking.

Contribution of External Gamma Rays to SPND at HANARO

Energy Technology Data Exchange (ETDEWEB)

Park, B. G.; Cho, D. K.; Kim, M. S.; Kang, G. D. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

Self-Powered Neutron Detectors (SPNDs) have been widely used for monitoring the neutron flux in reactors as well as in irradiation facilities. In its simplest form, the detector operates on the basis of directly measuring the beta decay current following neutron capture. The neutron capture cross-section of {sup 103}Rh, which is used for an emitter of the SPND, is 142.13 barns for thermal neutron (0.0253 eV). After neuron capture of {sup 103}Rh, the compound nuclei of {sup 104}Rh (92.6%) and {sup 104}mRh (7.4%) are produced. The sensitivity of SPND is generally defined as. The influence of water in the irradiation basket on the external gamma rays is determined by calculations of neutron capture reaction and photon interaction rates at various irradiation positions in HANARO. Since it is not easy to correct the contribution of the external gamma rays to the current signal by measurements at the research reactor, it is advantageous to reduce materials such as water at the irradiation position.

Radiosensitivity of lentil beam (Lens culinaris L.) to gamma-irradiation

Energy Technology Data Exchange (ETDEWEB)

Lee, Min Kyu; Ryu, Jaihyunk; Jeong, Sang Wook; Kim, Jin Baek; Kang, Si Young; Kwon, Soon Jae [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

2017-02-15

We examined damages from gamma-irradiation and determined the optimal gamma ray dose for mutation breeding in lentil (Lens culinaris L.) bean. Four individual lines (L-C, L-2, L-8 and L-9), that have remarkable adaptability in South Korea were gamma-irradiated at doses of 50, 70, 100, 200, 300, 400, and 500 Gy. The germination rate of seed decreased as the dose increased over 50 Gy in all lines. However, LD{sub 50} and RD{sub 50} were different among lines. The median lethal doses (LD50) were approximately 127 (L-C), 74 (L-2), 95 (L-8), and 144 (L-9) Gy. The median reduction doses (RD{sub 50}) for plant height, number of leaves, root length, and flash weight were 156, 176, 150, and 180 Gy for L-C, 253, 198, 127, and 142 Gy for L-2, 188, 175, 200, and 190 Gy for L-8, and 162, 210, 224, and 184 for L-9, respectively. The growth characteristics of the M1 generation decreased as the dose increased over 70 Gy. The optimal doses of gamma irradiation for mutation breeding of lentil were determined to be 70 Gy (L-2, L-8) and 100 Gy (L-C, L-9). We performed the comet assay to observe nuclear DNA damage induced by gamma-irradiation. In comet assay, a clear difference was identified over 100 Gy treatments. With increasing doses of gamma-ray in the range of 50 to 500 Gy, the rate of head DNA was decreased significantly from 97.5% to 81.6%. Tail length was consecutively increased from 1.9 μm to 17.4 μm. Our result provides basic information for construction of mutant pools in lentils.

Radiosensitivity of lentil beam (Lens culinaris L.) to gamma-irradiation

International Nuclear Information System (INIS)

Lee, Min Kyu; Ryu, Jaihyunk; Jeong, Sang Wook; Kim, Jin Baek; Kang, Si Young; Kwon, Soon Jae

2017-01-01

We examined damages from gamma-irradiation and determined the optimal gamma ray dose for mutation breeding in lentil (Lens culinaris L.) bean. Four individual lines (L-C, L-2, L-8 and L-9), that have remarkable adaptability in South Korea were gamma-irradiated at doses of 50, 70, 100, 200, 300, 400, and 500 Gy. The germination rate of seed decreased as the dose increased over 50 Gy in all lines. However, LD_5_0 and RD_5_0 were different among lines. The median lethal doses (LD50) were approximately 127 (L-C), 74 (L-2), 95 (L-8), and 144 (L-9) Gy. The median reduction doses (RD_5_0) for plant height, number of leaves, root length, and flash weight were 156, 176, 150, and 180 Gy for L-C, 253, 198, 127, and 142 Gy for L-2, 188, 175, 200, and 190 Gy for L-8, and 162, 210, 224, and 184 for L-9, respectively. The growth characteristics of the M1 generation decreased as the dose increased over 70 Gy. The optimal doses of gamma irradiation for mutation breeding of lentil were determined to be 70 Gy (L-2, L-8) and 100 Gy (L-C, L-9). We performed the comet assay to observe nuclear DNA damage induced by gamma-irradiation. In comet assay, a clear difference was identified over 100 Gy treatments. With increasing doses of gamma-ray in the range of 50 to 500 Gy, the rate of head DNA was decreased significantly from 97.5% to 81.6%. Tail length was consecutively increased from 1.9 μm to 17.4 μm. Our result provides basic information for construction of mutant pools in lentils

Building lab-scale x-ray tube based irradiators

International Nuclear Information System (INIS)

Haff, Ron; Jackson, Eric; Gomez, Joseph; Light, Doug; Follett, Peter; Simmons, Greg; Higbee, Brad

2016-01-01

Here we report the use of x-ray tube based irradiators as alternatives to gamma sources for laboratory scale irradiation. Irradiators were designed with sample placement in closest possible proximity to the source, allowing high dose rates for small samples. Designs using 1000 W x-ray tubes in single tube, double tube, and four tube configurations are described, as well as various cabinet construction techniques. Relatively high dose rates were achieved for small samples, demonstrating feasibility for laboratory based irradiators for research purposes. Dose rates of 9.76, 5.45, and 1.7 Gy/min/tube were measured at the center of a 12.7 cm container of instant rice at 100 keV, 70 keV, and 40 keV, respectively. Dose uniformity varies dramatically as the distance from source to container. For 2.54 cm diameter sample containers containing adult Navel Orangeworm, dose rates of 50–60 Gy/min were measured in the four tube system. - Highlights: • X-ray is demonstrated as an alternative to gamma for lab-based irradiation. • Cabinets using one, two, and four 1000 W tubes are reported. • Dose rate of 9.8 Gy/min/tube at the center of a 12.7 cm container of instant rice. • Dose uniformity varies dramatically as the distance from source to container.

Alteration of UV primary fluorescence of vital tumor cells following irradiation with neutrons and gamma rays

International Nuclear Information System (INIS)

Merkle, K.

1980-01-01

The change of UV primary fluorescence intensity of vital unstained cells of Ehrlich ascites carcinoma after 60 Co-gamma and neutron irradiation was investigated. The mean neutron energy was 6.2 MeV. Fluorescence intensity was detected using impulse cytophotometry. The UV intensity of single cells was measured in the spectral range from 300-400 nm. An monotonous increase of dose-effect curves and a maximum at 3.5 Gy (neutrons) and 30 Gy (γ-rays) was obtained. The first relevant increase of fluorescence intensity was detected at 0.4 Gy (neutrons) and 0.75 Gy (γ-rays). Factors influencing the increase and decrease of primary fluorescence behavior of vital cells are discussed. (author)

Life shortening, tumor induction, and tissue dose for fission-neutron and gamma-ray irradiations

International Nuclear Information System (INIS)

Grahn, D.; Duggal, K.; Lombard, L.S.

1985-01-01

The primary focus of this program is to obtain information on the late effects of whole body exposure to low doses of a high linear-energy-transfer (LET) and a low-LET ionizing radiation in experimental animals to provide guidance for the prediction of radiation hazards to man. The information obtained takes the form of dose-response curves for life shortening and for the induction of numerous specific types of tumors. The animals are irradiated with fission neutrons from the Janus reactor and with 60 Co gamma rays, delivered as single, weekly, or duration-of-life exposures covering the range of doses and dose rates. 6 refs

Influence of the molecular modifications on the properties of EPDM elastomers under irradiation

International Nuclear Information System (INIS)

Davenas, J.; Stevenson, I.; Celette, N.; Vigier, G.; David, L.

2003-01-01

The degradation of the mechanical behaviour of EPDM elastomers used as cable insulation materials has been investigated by mechanical spectroscopy and tensile tests for different formulations: unvulcanised EPDM, vulcanised and stabilised elastomer with an antioxidant. In all cases, γ-irradiation of EPDM under oxygen leads to a reduction of the molecular mobility indicated by the shift of the glass transition relaxation temperature towards higher temperatures. Moreover, the molecular flow occurring above T g is suppressed after irradiation for the unvulcanised EPDM providing evidence of cross-linking. The competition between cross-linking and chain scissions is shown by the decrease of the storage modulus above the crystallites melting temperature (∼40 deg. C) at doses larger than 100 kGy. A strong increase of the Young modulus and reduction of the elongation at break of the non-vulcanised EPDM becoming more brittle are shown by stress/strain characterisations performed at 80 deg. C. At the opposite vulcanised EPDM exhibits higher elongation at break after crystallites melting. This evolution is interpreted by the competition between cross-linking and chain scissions, being hindered by the crystallites at room temperature. The intrinsic irradiation effects can be isolated after crystallite melting. The reduction of the molecular mobility can be explained by a chemi-crystallisation process assisted by chain scissions, leading to a more rigid phase upon irradiation

Gamma Irradiation does not Cause Carcinogenesis of Irradiated Herbs

International Nuclear Information System (INIS)

Thongphasuk, Jarunee; Thongphasuk, Piyanuch; Eamsiri, Jarurut; Pongpat, Suchada

2009-07-01

Full text: Microbial contamination of medicinal herbs can be effectively reduced by gamma irradiation. Since irradiation may cause carcinogenicity of the irradiated herbs, the objective of this research is to study the effect of gamma irradiation (10 and 25 kGy) from cobalt-60 on carcinogenicity. The herbs studied were Pueraria candollei Grah., Curcuma longa Linn. Zingiber montanum, Senna alexandrina P. Miller, Eurycoma Longifolia Jack, Gymnostema pentaphylum Makino, Ginkgo biloba, Houttuynia cordata T., Andrographis paniculata, Thunbergia laurifolia L., Garcinia atroviridis G., and Cinnamomum verum J.S.Presl. The results showed that gamma irradiation at the dose of 10 and 25 kGy did not cause carcinogenicity of the irradiated herbs

Biochemical changes in garlic (Allium sativum L. ) during storage following [gamma]-irradiation

Energy Technology Data Exchange (ETDEWEB)

Croci, C.A.; Orioli, G.A. (Univ. Nacional del Sur, Bahia Blanca (Argentina)); Arguello, J.A. (Univ. Nacional de Cordoba (Argentina))

1994-02-01

The aim of this paper was to evaluate an acute dose of [gamma]-rays (10 Gy) on post-dormant garlic seed cloves in terms of total DNA, total RNA, total protein and soluble carbohydrates in order to correlate these levels with sprouting inhibition induced by [gamma]-irradiation. Decreases in total DNA content were found in inner sprouts immediately and 100 days after irradiation. The total RNA and protein contents and the carbohydrate content of the storage leaf or the inner sprout were not affected by [gamma]-irradiation. The results support the notion that in post-dormant garlic seed cloves, DNA content and its behaviour seem to be among the sensitive cellular responses to radiation. (author).

Effects of gamma ray and electron beam irradiation on reduction of microbial load and antioxidant properties of Chum-Hed-Thet (Cassia alata (L.) Roxb.)

Science.gov (United States)

Prakhongsil, P.; Pewlong, W.; Sajjabut, S.; Chookaew, S.

2017-06-01

Considering the growing demands of herbal medicines, Cassia alata (L.) Roxb. has been reported to have various phytochemical activities. It has also been called in Thai as Chum-Hed-Thet. In this study, C. alata (L.) Roxb. powder were exposed to gamma and electron beam irradiation at doses of 0, 5, 10, 15 and 20 kGy. At the dose of 10 kGy, both of gamma and electron beam irradiation were sufficient in reducing microbial load of irradiated samples as specified in Thai pharmacopoeia (2005). These include the total aerobic microbial count of bacteria of 0.05). Therefore, both of radiation by gamma ray or electron beam at 10 kGy was sufficient in elimination of microbial flora and did not significantly affected the total phenolic content and antioxidant activities of C. alata (L.) Roxb.

Activation of wine bentonite with gamma rays

International Nuclear Information System (INIS)

Goranov, N.; Antonov, M.

1997-01-01

The action of gamma rays on wine bentonite as well as influence of its adsorption and technologic qualities on the composition and stability of wines against protein darkening and precipitation has been studied. The experiments were carried out with wine bentonite produced in the firm Bentonite and irradiated with doses of 0.4, 0.6, 0.8 and 1.0 MR. White and red wines have been treated with irradiated bentonite under laboratory conditions at 1.0 g/dm 3 . All samples are treated at the same conditions. The flocculation rate of the sediment was determined visually. Samples have been taken 24 h later from the cleared wine layers. The following parameters have been determined: clarification, filtration rate, phenolic compounds, calcium, colour intensity, total extracted substances, etc. The volume of the sediment has been determined also. The control samples have been taken from the same unirradiated wines. The results showed better and faster clarification in on the third, the 20th and the 24th hours with using of gamma-irradiated at doses 0.8 and 1.0 MR. The sediment was the most compact and its volume - the smallest compared to the samples treated with bentonite irradiated with doses of 0.6 and 0.4 MR. This ensures a faster clarification and better filtration of treated wines. The bentonite activated with doses of 0.8 and 1.0 MR adsorbs the phenolic compounds and the complex protein-phenolic molecules better. In the same time it adsorbs less extracted substances compared to untreated bentonite and so preserves all organoleptic properties of wine. The irradiated bentonite adsorbs less the monomers of anthocyan compounds which ensures brighter natural colour of wine. The gamma-rays activation consolidates calcium in the crystal lattice of bentonite particles and in this way eliminates the formation of crystal precipitates

Effect Of Gamma Ray Irradiation On Streptococcus Agalactiae Growth For Vaccine Agent Of Mastitis Disease In Dairy Cattle

International Nuclear Information System (INIS)

Jeane Tuasikal, B; Sugoro, I; Tjiptosumirat, T; Lina, M

2003-01-01

A study has been conducted to determine the effect of gamma ray irradiation to attenuate infectivity of S. agalactiae as dominant bacteria causing mastitis in dairy cattle. The aim of the study is obtaining optimum irradiation dosage to provide radio vaccine for mastitis. S. agalactiae isolate bacteria of which has reach the mid log-phase was cultured and divided into 6 treatment groups of irradiation doses, i.e. 0, 0.2, 0.4, 0.6, 0.8, and 1.0 kGy. Following irradiation, bacteria were then cultured in BHI agar media for colony counting to determine the LD 50 , resulting 7.5x10 8 ; 5.0x10 7 ; 7.0x10 6 ; 9.5x10 5 ; 1.5x10 4 ; and 3.5x10 3 cell/ml, respectively. Result of this study shows the higher irradiation doses the lower number of bacteria per ml, and LD 50 , which found to be under 0.2 kGy of irradiation dose

Effect of gamma irradiation on some physiological processes during maiz. seed germination

Energy Technology Data Exchange (ETDEWEB)

Kerin, V; Ilieva, T [Vissh Selskostopanski Inst., Plovdiv (Bulgaria)

1976-01-01

The investigation was carried out with the SK/sub 4/ and Knezha 2L-403 hybrids. Dry seeds were irradiated by ..gamma..-rays in doses of 500 R, 750 R and 1000 R radioactive cesium 137. The effect of the individual ..gamma..-ray doses on sprout and root growth, respiration rate and peroxidase activity was followed up. Results showed that seed irradiation by a 500R dose had a stimulating effect on sprout and root growth, while the 750 R and 1000 R did not differ significantly from the ccntrol. Seed irradiation by 500 R reduced the respiration rate of the roots and sprouts, while both treatments with higher doses gave results similar to the control. The changes in the respiration enzyme peroxidase were in correlation with the changes in respiration rate.

Unilateral irradiation of pigs in a mixed neutrons+gamma field. Early results

International Nuclear Information System (INIS)

Lemaitre, Guy; Maas, Jean.

1982-08-01

Pigs (16-20kg) were irradiated with 60 Co gamma or in a mixed field (neutron + gamma from the pulsed reactor SILENE). Pigs were unilaterally exposed by the left side. Each experimental group was composed of twelve animals and one control. Within the dose range explored (reference dose is mid-line tissue dose): 4-9.8 Gy of gamma rays only; 4.6 - 5.7 Gy of neutrons and gamma rays, pigs presented the haematopioetic form of the acute radiation sickness. At 5 Gy mixed field was more harmful than gamma rays only. Therefore the numerical value of neutron RBE (lethality 50 p cent within 30 days) is more than one. Experiments will be carried out in order to determine RBE values more accurately. Bone marrow dose will also be determined [fr

Dose calculation method with 60-cobalt gamma rays in total body irradiation

International Nuclear Information System (INIS)

Scaff, Luiz Alberto Malaguti

2001-01-01

Physical factors associated to total body irradiation using 60 Co gamma rays beams, were studied in order to develop a calculation method of the dose distribution that could be reproduced in any radiotherapy center with good precision. The method is based on considering total body irradiation as a large and irregular field with heterogeneities. To calculate doses, or doses rates, of each area of interest (head, thorax, thigh, etc.), scattered radiation is determined. It was observed that if dismagnified fields were considered to calculate the scattered radiation, the resulting values could be applied on a projection to the real size to obtain the values for dose rate calculations. In a parallel work it was determined the variation of the dose rate in the air, for the distance of treatment, and for points out of the central axis. This confirm that the use of the inverse square law is not valid. An attenuation curve for a broad beam was also determined in order to allow the use of absorbers. In this work all the adapted formulas for dose rate calculations in several areas of the body are described, as well time/dose templates sheets for total body irradiation. The in vivo dosimetry, proved that either experimental or calculated dose rate values (achieved by the proposed method), did not have significant discrepancies. (author)

The effects of gamma-ray irradiation to strawberry (Fragaria x ananassa Duch.) calli on shoot regeneration, achene formation and morphological variations of regenerants

International Nuclear Information System (INIS)

Kasumi, Masakazu

2002-01-01

Strawberry (Fragaria x ananassa 'Nyoho') calli, derived from anthers, were irradiated with gamma -ray at dosages from 100 to 1,600 Gy (10 Gy · hr - 1) and their effects on callus growth, plant regeneration, and somaclonal variation were analyzed. The growth of callus and percentage of plant regeneration from the callus were reduced slightly at dosages less than 200 Gy, moderately at 400 Gy, and markedly above 800 Gy. Fruit growth associated with seed fertility (>50 % ) was morphologically normal at less than 100 Gy, whereas achene formation was significantly inhibited above 200 Gy. The percentages of morphological variation in regenerants formed from the irradiated callus were:13.7 (no irradiation), 18.6 (100 Gy), 66.0 (200 Gy), 75.7 (400 Gy), and 97.0 (800 Gy). Furthermore, higher dosages yielded wider variations, e.g., thick and small leaf, light leaf color, white flesh, and long fruit. In some regenerants, more than one morphological aberrations developed, some of which were transmissible to daughter plants. These results revealed that the irradiating strawberry callus with gamma - ray resulted in a higher degree and wider spectrum of somaclonal variation than did simple callus culture. (author)

External gamma irradiation-induced effects in early-life stages of zebrafish, Danio rerio

International Nuclear Information System (INIS)

Gagnaire, B.; Cavalié, I.; Pereira, S.; Floriani, M.; Dubourg, N.; Camilleri, V.; Adam-Guillermin, C.

2015-01-01

Highlights: • The present study aimed to evaluate the effects of gamma rays on zebrafish larvae. • Different techniques were used: gene expression, biochemistry, microscopy and macroscopical observations. • The results showed that gamma irradiation can alter embryo-larval development at several levels of organization. - Abstract: In the general context of validation of tools useful for the characterization of ecological risk linked to ionizing radiation, the effects of an external gamma irradiation were studied in zebrafish larvae irradiated for 96 h with two dose rates: 0.8 mGy/d, which is close to the level recommended to protect ecosystems from adverse effects of ionizing radiation (0.24 mGy/d) and a higher dose rate of 570 mGy/d. Several endpoints were investigated, such as mortality, hatching, and some parameters of embryo-larval development, immunotoxicity, apoptosis, genotoxicity, neurotoxicity and histological alterations. Results showed that an exposure to gamma rays induced an acceleration of hatching for both doses and a decrease of yolk bag diameter for the highest dose, which could indicate an increase of global metabolism. AChE activity decreased with the low dose rate of gamma irradiation and alterations were also shown in muscles of irradiated larvae. These results suggest that gamma irradiation can induce damages on larval neurotransmission, which could have repercussions on locomotion. DNA damages, basal ROS production and apoptosis were also induced by irradiation, while ROS stimulation index and EROD biotransformation activity were decreased and gene expression of acetylcholinesterase, choline acetyltransferase, cytochrome p450 and myeloperoxidase increased. These results showed that ionizing radiation induced an oxidative stress conducting to DNA damages. This study characterized further the modes of action of ionizing radiation in fish.

External gamma irradiation-induced effects in early-life stages of zebrafish, Danio rerio

Energy Technology Data Exchange (ETDEWEB)

Gagnaire, B., E-mail: beatrice.gagnaire@irsn.fr [Institut de Radioprotection et de Sureté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Cavalié, I. [Institut de Radioprotection et de Sureté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Pereira, S. [Neolys Diagnostics, Lyon 69373 (France); Floriani, M.; Dubourg, N.; Camilleri, V.; Adam-Guillermin, C. [Institut de Radioprotection et de Sureté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France)

2015-12-15

Highlights: • The present study aimed to evaluate the effects of gamma rays on zebrafish larvae. • Different techniques were used: gene expression, biochemistry, microscopy and macroscopical observations. • The results showed that gamma irradiation can alter embryo-larval development at several levels of organization. - Abstract: In the general context of validation of tools useful for the characterization of ecological risk linked to ionizing radiation, the effects of an external gamma irradiation were studied in zebrafish larvae irradiated for 96 h with two dose rates: 0.8 mGy/d, which is close to the level recommended to protect ecosystems from adverse effects of ionizing radiation (0.24 mGy/d) and a higher dose rate of 570 mGy/d. Several endpoints were investigated, such as mortality, hatching, and some parameters of embryo-larval development, immunotoxicity, apoptosis, genotoxicity, neurotoxicity and histological alterations. Results showed that an exposure to gamma rays induced an acceleration of hatching for both doses and a decrease of yolk bag diameter for the highest dose, which could indicate an increase of global metabolism. AChE activity decreased with the low dose rate of gamma irradiation and alterations were also shown in muscles of irradiated larvae. These results suggest that gamma irradiation can induce damages on larval neurotransmission, which could have repercussions on locomotion. DNA damages, basal ROS production and apoptosis were also induced by irradiation, while ROS stimulation index and EROD biotransformation activity were decreased and gene expression of acetylcholinesterase, choline acetyltransferase, cytochrome p450 and myeloperoxidase increased. These results showed that ionizing radiation induced an oxidative stress conducting to DNA damages. This study characterized further the modes of action of ionizing radiation in fish.

Proton and gamma -Rays Irradiation-Induced Dark Current Random Telegraph Signal in a 0.18-mu{{m}} CMOS Image Sensor

Science.gov (United States)

Martin, E.; Nuns, T.; Virmontois, C.; David, J.-P.; Gilard, O.

2013-08-01

The dark current random telegraph signal (RTS) behavior has been studied in a five-transistor-per-pixel (5T) pinned photodiode 0.18-μm COTS active pixel sensor (APS). Several devices, irradiated using protons and gamma rays, have been studied in order to assess the ionizing and displacement damage effects. The influence of the proton energy, fluence, ionizing dose and applied bias during irradiation on the number of RTS pixels, the number of discrete levels, maximum transition amplitude, and mean switching time constants is investigated.

Biosolubilization gamma irradiate ion result coal by mould trichoderma sp

International Nuclear Information System (INIS)

Pingkan Aditiawati; Dea Indriani Astuti; Irawan Sugoro; Dwiwahju Sasongko

2011-01-01

Biosolubilization of coal is process of converting solid coal to liquid fuel/chemicals by mean of microorganism. The aim of this research was to study the effect of gamma rays irradiation with varian doses of irradiation into solubilization of subbituminous coal by Trichoderma sp. The dosage used was 5, 10, and 20 kGy and unirradiated coal as control. The method was submerged culture in MSS+ medium and incubated at room temperature and agitated at 150 rpm for 21 th days. The parameters observed were colonization, pH and biosolubilization product based on absorbance value at λ 250nm and λ 450nm and GC/MS analysis for the best treatment. The results showed that coal biosolubilization could be increased by gamma irradiation. The mould could growth well in medium containing irradiated coal and the medium of pH was decreased after incubation. The biosolubilization was increased but the irradiation dosage of coal didn't affect significantly. The best dose was 20 kGy with product biosolubilization similar to gasoline and solar. Based on the result, the pre-treatment of gamma irradiation on coal has potency to increased biosolubilization. (author)

The influence of nano silica particles on gamma-irradiation ageing of elastomers based on chlorosulphonated polyethylene and acrylonitrile butadiene rubber

Science.gov (United States)

Marković, G.; Marinović-Cincović, M.; Tanasić, Lj.; Jovanović, V.; Samaržija-Jovanović, S.; Vukić, N.; Budinski-Simendić, J.

2011-12-01

The goal of this work was to study gamma irradiation ageing of rubber blends based on acrylonitrile butadiene rubber (NBR) and chlorosulphonated polyethylene rubber (CSM) reinforced by silica nano particles. The NBR/CSM compounds (50: 50, w/w) filled with different content of filler (0-100 phr) were crosslinked by sulfur. The vulcanization characteristics were assessed using the rheometer with an oscillating disk. The vulcanizates were prepared in a hydraulic press. The obtained materials were exposed to the different irradiation doses (100, 200, 300 and 400 kGy). The mechanical properties (hardness, modulus at 100% elongation, tensile strength and elongation at break) and swelling numbers were assessed before and after gamma irradiation ageing.

Biodegradation polyurethane derived from vegetable oil irradiated with gamma rays 25 kGy and 100 kGy

International Nuclear Information System (INIS)

Santos, Antonia M. dos; Claro Neto, Salvador; Azevedo, Elaine C. de

2011-01-01

The environment requires polymers that can be degraded by the action of microorganisms. In this work was studied the biodegradation of polyurethane samples derived from vegetable oil (castor oil), which were irradiated with gamma rays 25 kGy and 100 kGy compared with the same polyurethane without being irradiated. Biodegradation of polyurethane was carried out in culture medium containing the fungus Aspergillus niger by 146 days and the result was evaluated using the technique of thermogravimetric analysis, where there was a change of behavior of the curves TGA / DTG occurred indicating that chemical modifications of molecules present in the structure of the polymer chain, thus confirming that the material has undergone the action of microorganisms. (author)

Gamma irradiator

International Nuclear Information System (INIS)

Simonet, G.

1986-09-01

Fiability of devices set around reactors depends on material resistance under irradiation noticeably joints, insulators, which belongs to composition of technical, safety or physical incasurement devices. The irradiated fuel elements, during their desactivation in a pool, are an interesting gamma irradiation device to simulate damages created in a nuclear environment. The existing facility at Osiris allows to generate an homogeneous rate dose in an important volume. The control of the element distances to irradiation box allows to control this dose rate [fr

Cytochrome C effect on gamma-ray efficiency on barley seeds at different metabolic states

International Nuclear Information System (INIS)

Yankulov, M.

1981-01-01

Radiobiological studies of the effect of gamma-rays on the barley seeds were performed. It was shown that the different metabolic states of the seeds do not modify the effect of the independent treatment with cytochrome C, while the action of the gamma-rays is markedly modified. With the increase in the preliminary seed soaking time in H 2 O, the total lethality in the case of irradiated treatments rises from 54.10% to 91.00% and that of sterility to 13.13 and 57.44% for 12 and 72 hrs, respectively. The preliminary and post-irradiation treatment of seeds with cytochrome C markedly reduces the effect of gamma-rays, calculated by the criteria of general lethality and sterility, the trend towards an increase in the sensitivity with the increase in the extention of the preliminary soaking time of seeds in water being preserved. Preliminary soaking in the seeds in water also modifies the mutagenic effect of gamma-rays to a considerable extent. (author)

Characterization of Amylopectin irradiated by gamma rays using viscosity and radius gyration technique

International Nuclear Information System (INIS)

Ku Sarah Syahidah Ku Muhamad

2012-01-01

Food irradiation is one of the most applicable methods that have been used in food industry especially to preserve food. Besides preservation of food, irradiation can also reduce microorganism, inhibit budding and others. However, this method can be misused by some irresponsible organization or person such as irradiate the food over the dose limit value. Therefore, the detection method is important to detect any misused in irradiation method. The objective of this research is to identify any changes in the structure of amylopectin by using radius gyration technique. Besides that, the viscosity of the sample is also determined by using Rheometer. The last objective of this research is to find a relationship between radius gyration and irradiation dose can be determined. Amylopectin and cassava powder were the sample in this research. The samples were irradiated in the gamma-cell at 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0, and 10.0 kGy doses. 0 kGy were the controlled sample. The sample were made into gel to analysed using Rheometer and Small Angle X-ray Scattering (SAXS). The viscosity of the sample were analysed by using Rheometer while the radius gyration of the sample were analysed by using SAXS. Hence, the result of this experiment is, the viscosity of amylopectin reduces as the doses increases. But, at 10 kGy, the viscosity of the cassava starch was increased significantly. For the SAXS analysis, it is shows that the graph for amylopectin were fluctuates. While, for cassava starch the radius gyration increases with doses. Hence, the rheometer technique is suitable to be develop as a detection method in food irradiation. Further research should be done to improve the detection technique in food irradiation. (author)

Effects of gamma irradiation of an isolated flower in reproductive stages on seed production of Brassica napus L

International Nuclear Information System (INIS)

Minami, Harufumi; Sakurai, Noboru; Muroyama, Takeo; Hogetsu, Daisuke

1999-01-01

We examined seed production after gamma irradiation of an isolated whole flower (a flower with pedicel) of Brassica napus strain 1 through a flower organ culture and estimated the effects of gamma rays on embryogenesis in sexual reproductive stages. The whole flowers were irradiated with 17, 32, 57 and 87 Gy of gamma rays in unpollinated stage at day of anthesis, in stage shortly after fertilization and early embryo stage. The gamma irradiation of flowers in stage shortly after fertilization showed a drastic effect on the mature seed production. The number of seeds per pod began to decrease at 17 Gy and dropped to 15% of that of unirradiated flowers at 32 Gy. On the other hand, the flowers irradiated in the unpollinated and early embryo stages began to reduce the number of seeds at 57 Gy. The ovary elongation was suppressed with increasing irradiation dose when the flower was irradiated in unpollinated stage and stage shortly after fertilization. (author)

Mechanical Property Of Zeolite-PVA Composite Mixture Irradiated By Gamma Ray Of Co-60

International Nuclear Information System (INIS)

Darsono; Danu, Sugiarto; Las, Tamzil

2000-01-01

Experiment on preparation of zeolite-polyvinyl alcohol composite for absorbance materials have been done by curring using Gamma γ-ray of Co-60. Zeolite with the particles size of 60 mesh was mixed with polyvinyl alcohol (PVA) at the concentration of the mixture were 6,9, and 12% by weight, than they were poured into glass tube (length = 100 mm; diameter = 10 mm) and irradiated at the doses of 10, 20, 30 dan 40 kGy with the dose rate of 7,5 kGy/ hr. Parameters observed were density, compressive strength, and hardness. Experimental results showed that polyvinyl alcohol in the mixture was significant effect to density and compressive strength, where as the irradiation dose was highly significant effect to compressive strength. The effect interaction between dose and polyvinyl alcohol concentration factors had significant effect to density or compressive strength. Almost all samples have pencil hardness of 4 - 5 H, for composite containing 6 % PVA, has pencil hardness of 2 - 3 H

A comparison of ionizing radiation damage in CMOS devices from 60Co gamma rays, electrons and protons

International Nuclear Information System (INIS)

He Baoping; Yao Zhibin; Zhang Fengqi

2009-01-01

Radiation hardened CC4007RH and non-radiation hardened CC4011 devices were irradiated using 60 Co gamma rays, 1 MeV electrons and 1-9 MeV protons to compare the ionizing radiation damage of the gamma rays with the charged particles. For all devices examined, with experimental uncertainty, the radiation induced threshold voltage shifts (ΔV th ) generated by 60 Co gamma rays are equal to that of 1 MeV electron and 1-7 MeV proton radiation under 0 gate bias condition. Under 5 V gate bias condition, the distinction of threshold voltage shifts (ΔV th ) generated by 60 Co gamma rays and 1 MeV electrons irradiation are not large, and the radiation damage for protons below 9 MeV is always less than that of 60 Co gamma rays. The lower energy the proton has, the less serious the radiation damage becomes. (authors)

Effect of gamma irradiation on the cigarette beetles reared on cayenne pepper

International Nuclear Information System (INIS)

Imamura, Taro; Miyanoshita, Akihiro; Todoriki, Setsuko

2009-01-01

Effect of gamma irradiation on the survival of the cigarette beetles reared on cayenne pepper was investigated. Gamma ray at a dose of 62 Gy completely killed eggs and larvae of the beetles. Some pupae survived at 540 Gy, but all pupae were killed at 1076 Gy. (author)

Gamma irradiation improves the antioxidant activity of Aloe vera (Aloe barbadensis miller) extracts

International Nuclear Information System (INIS)

Lee, Eun Mi; Bai, Hyoung-Woo; Lee, Seung Sik; Hong, Sung Hyun; Cho, Jae-Young; Byung, Yeoup Chung

2012-01-01

Aloe has been widely used in food products, pharmaceuticals, and cosmetics because of its aromatic and therapeutic properties. In the present study, the ethanolic extracts of aloe gel were gamma-irradiated from 10 to 100 kGy. After gamma irradiation, the color of the ethanolic extracts of aloe gel changed to red; this color persisted up to 40 kGy but disappeared above 50 kGy. Liquid chromatography/mass spectrometry analysis demonstrated the production of a new, unknown compound (m/z=132) after gamma irradiation of the ethanolic extracts of aloe gel. The amount of this unknown compound increased with increasing irradiation up to 80 kGy, and it was degraded at 100 kGy. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by the 1,1-diphenyl-2-picrylhydrazyl-radical scavenging capacity. The antioxidant activity of aloe extract was dramatically increased from 53.9% in the non-irradiated sample to 92.8% in the sample irradiated at 40 kGy. This strong antioxidant activity was retained even at 100 kGy. These results indicate that gamma irradiation of aloe extract can enhance its antioxidant activity through the formation of a new compound. Based on these results, increased antioxidant activity of aloe extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.

Gamma irradiation improves the antioxidant activity of Aloe vera (Aloe barbadensis miller) extracts

Science.gov (United States)

Mi Lee, Eun; Bai, Hyoung-Woo; Sik Lee, Seung; Hyun Hong, Sung; Cho, Jae-Young; Yeoup Chung, Byung

2012-08-01

Aloe has been widely used in food products, pharmaceuticals, and cosmetics because of its aromatic and therapeutic properties. In the present study, the ethanolic extracts of aloe gel were gamma-irradiated from 10 to 100 kGy. After gamma irradiation, the color of the ethanolic extracts of aloe gel changed to red; this color persisted up to 40 kGy but disappeared above 50 kGy. Liquid chromatography/mass spectrometry analysis demonstrated the production of a new, unknown compound (m/z=132) after gamma irradiation of the ethanolic extracts of aloe gel. The amount of this unknown compound increased with increasing irradiation up to 80 kGy, and it was degraded at 100 kGy. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by the 1,1-diphenyl-2-picrylhydrazyl-radical scavenging capacity. The antioxidant activity of aloe extract was dramatically increased from 53.9% in the non-irradiated sample to 92.8% in the sample irradiated at 40 kGy. This strong antioxidant activity was retained even at 100 kGy. These results indicate that gamma irradiation of aloe extract can enhance its antioxidant activity through the formation of a new compound. Based on these results, increased antioxidant activity of aloe extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.

Thermoluminescence properties of Al2O3:Tb nanoparticles irradiated by gamma rays and 85 MeV C6+ ion beam

International Nuclear Information System (INIS)

Salah, Numan; Alharbi, Najlaa D.; Habib, Sami S.; Lochab, S.P.

2015-01-01

Carbon ions beam is recently recognized as an ideal cancer treatment modality, because of its excellent local tumor control. These ions have a high relative biological effectiveness resulting from high linear energy transfer (LET) and their sharp Bragg peak. However, the dose of those energetic ions needs to be measured with great precision using a proper dosimeter. Aluminum Oxide (Al 2 O 3 ) is a highly luminescent phosphor widely used for radiation dosimetry using thermoluminesence (TL) technique. In this work nanoparticles of this material activated by different elements like Eu, Tb, Dy, Cu and Ag were evaluated for their TL response to gamma rays irradiation. Tb doped sample is found to be the most sensitive sample, which could be selected for exposure to 85 MeV C 6+ ion beam in the fluence range 10 9 –10 13 ions/cm 2 . The obtained result shows that C ion beam irradiated sample has a simple glow curve structure with a prominent glow peak at around 230 °C. This glow curve has a dosimetric peak better than those induced by gamma rays. This glow peak exhibits a linear response in the range 10 9 –10 11 ions/cm 2 , corresponding to the equivalent absorbed doses 0.285–28.5 kGy. The absorbed doses, penetration depths and main energy loss were calculated using TRIM code based on the Monte Carlo simulation. The wide linear response of Al 2 O 3 :Tb nanoparticles along with the low fading makes this low cost nanomaterial a good candidate for C ion beam dosimetry. - Highlights: • Nanoparticles of Al 2 O 3 doped with Eu, Tb, Dy, Cu and Ag were synthesised. • They were evaluated for their TL response to gamma rays and C ion beam irradiation. • Tb doped sample is the most sensitive sample to gamma rays. • Al 2 O 3 :Tb was exposed to 85 MeV C 6+ ion beam in the fluence range 10 9 -10 13 ions/cm 2 . • The glow peak induced by C ions has a linear response in the range 10 9 -10 11 ions/cm 2

The influence of maize kernel moisture on the sterilizing effect of gamma rays

International Nuclear Information System (INIS)

Khanymova, T.; Poloni, E.

1980-01-01

The influence of 4 levels of maize kernel moisture (16, 20, 25 and 30%) on gamma-ray sterilizing effect was studied and the after-effect of radiation on the microorganisms at short term storage was followed up. Maize kernels of the hybrid Knezha-36 produced in 1975 were used. Gamma-ray treatment of the kernels was effected by GUBEh-4000 irradiator at doses of 0.2 and 0.3 Mrad and after that they were stored for a month at 12 deg and 25 deg C and controlled moisture conditions. Surface and subepidermal infection of the kernels was determined immediately post irradiation and at the end of the experiment. Non-irradiated kernels were used as controls. Results indicated that the initial kernel moisture has a considerable influence on the sterilizing effect of gamma-rays at the rates used in the experiment and affects to a considerable extent the post-irradiation recovery of organisms. The speed of recovery was highest in the treatment with 30% moisture and lowest in the treatment with 16% kernel moisture. Irradiation of the kernels causes pronounced changes on the surface and subepidermal infection. This was due to the unequal radio resistance to the microbial components and to the modifying effect of the moisture holding capacity. The useful effect of maize kernel irradiation was more prolonged at 12 deg C than at 25 deg C