The radiation field measurement and analysis outside the shielding of A 10 MeV electron irradiation accelerator

Energy Technology Data Exchange (ETDEWEB)

Shang Jing [National Synchrotron Radiation Lab, University of Science and Technology of China (China); Li Juexin, E-mail: juexin@ustc.edu.cn [National Synchrotron Radiation Lab, University of Science and Technology of China (China); Xu Bing; Li Yuxiong [National Synchrotron Radiation Lab, University of Science and Technology of China (China)

2011-10-01

Electron accelerators are employed widely for diverse purposes in the irradiation-processing industry, from sterilizing medical products to treating gemstones. Because accelerators offer high efficiency, high power, and require little preventative maintenance, they are becoming more and more popular than using the {sup 60}Co isotope approach. However, the electron accelerator exposes potential radiation hazards. To protect workers and the public from exposure to radiation, the radiation field around the electronic accelerator must be assessed, especially that outside the shielding. Thus, we measured the radiation dose at different positions outside the shielding of a 10-MeV electron accelerator using a new data-acquisition unit named Mini-DDL (Mini-Digital Data Logging). The measurements accurately reflect the accelerator's radiation status. In this paper, we present our findings, results and compare them with our theoretical calculations. We conclude that the measurements taken outside the irradiation hall are consistent with the findings from our calculations, except in the maze outside the door of the accelerator room. We discuss the reason for this discrepancy.

Preliminary research concerning the using of electron accelerator for irradiation of fresh seasonal fruits

International Nuclear Information System (INIS)

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

1994-01-01

There were performed preliminary electron-beam irradiation of strawberries, cherries, and sour cherries. The irradiations were carried out with the IPTRD's electron acceleration at 6 MeV, at different dose-rates, particularly at 1-3 kGy for strawberries, and 0.5-2.0 kGy for cherries. The dosimetry was performed using a PTW medical dosemeter. After irradiation the samples were controlled and preserved at 8-10 o C, 75-85% r.h. The fruits were then analysed for organoleptic and nutritional preservation characteristics , sugars, acidity, C-vitamin, etc. They were also examined in order to find criteria for identification of irradiated fruits. The results show a good shelf-life extension for 5-15 days and the suggest the capability of using the electron-beam irradiation technologies in agro-food industry. (Author)

Radiation doses inside industrial irradiation installation with linear electron accelerator

International Nuclear Information System (INIS)

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

2015-01-01

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

Radiation doses inside industrial irradiation installation with linear electron accelerator

Energy Technology Data Exchange (ETDEWEB)

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

2015-07-01

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

Development of 350 keV electron accelerator

International Nuclear Information System (INIS)

Qin Jiuchang; Cui Shan; Zhou Wenzhen; Cui Zhipeng; Shi Zhenghu; Lu Zhongcheng; Chen Shangwen; Zhang Lifeng; Cui Zongwei; Huang Jun; Yin Meng

2007-01-01

The 350 keV electron accelerator is used for irradiation and production of plas- tic film of the medical infusion bags. The body structure of Van de Graft accelerator and the high voltage power supply of Cockcrof-Walton accelerator are adopted in the electron accelerator. The 350 keV DC power supply is supplied by the high frequency power supply with 14 kHz and 35 kW. The body and DC power supply of the electron accelerator are installed in the tank filled with 0.3 MPa SF 6 . The electron accelerator is compact, self-shielding and suitable for on-line electron beam processing. The main characteristics of the facility are terminal voltage 370 kV, electron beam power 7 kW (350 keV/20 mA), scaning width 70 cm, irradiation dose inuniformity ≤7%. (authors)

The electron accelerator Ridgetron

International Nuclear Information System (INIS)

Hayashizaki, N.; Hattori, T.; Odera, M.; Fujisawa, T.

1999-01-01

Many electron accelerators of DC or RF type have been widely used for electron beam irradiation (curing, crosslinking of polymers, sterilization of medical disposables, preservation of food, etc.). Regardless of the acceleration energy, the accelerators to be installed in industrial facilities, have to satisfy the requires of compact size, low power consumption and stable operation. The DC accelerator is realized very compact in the energy under 300 keV, however, it is large to prevent the discharge of an acceleration column in the energy over 300 keV. The RF electron accelerator Ridgetron has been developed to accelerate the continuous beam of the 0.5-10 MeV range in compact space. It is the first example as an electron accelerator incorporated a ridged RF cavity. A prototype system of final energy of 2.5 MeV has been studied to confirm the feasibility at present

Industrial applications of electron beam accelerators

International Nuclear Information System (INIS)

Braid, W.G. Jr.

1976-01-01

The use of electron beam accelerators for crosslinking polyolefins for shrinking food packaging is discussed. Irradiation procedures, accelerator characteristics, and industrial operations are described

Dose distributions in electron irradiated plastic tubing

International Nuclear Information System (INIS)

Miller, A.; Pederson, W.B.

1981-01-01

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

Volumetric change of simulated radioactive waste glass irradiated by electron accelerator. [Silica glass

Energy Technology Data Exchange (ETDEWEB)

Sato, Seichi; Furuya, Hirotaka; Inagaki, Yaohiro; Kozaka, Tetsuo; Sugisaki, Masayasu

1987-11-01

Density changes of simulated radioactive waste glasses, silica glass and Pyrex glass irradiated by an electron accelerator were measured by a ''sink-float'' technique. The density changes of the waste and silica glasses were less than 0.05 %, irradiated at 2.0 MeV up to the fluence of 1.7 x 10/sup 17/ ecm/sup 2/, while were remarkably smaller than that of Pyrex glass of 0.18 % shrinkage. Precision of the measurements in the density changes of the waste glass was lower than that of Pyrex glass possibly because of the inhomogeneity of the waste glass

Prototype of industrial electrons accelerator

International Nuclear Information System (INIS)

Lopez, V.H.; Valdovinos, A.M.

1992-01-01

The interest and the necessity of Mexico's industry in the use of irradiation process has been increased in the last years. As examples are the irradiation of combustion gases (elimination of NO x and SO 2 ) and the polymer cross-linking between others. At present time at least twelve enterprises require immediately of them which have been contacted by electron accelerators suppliers of foreign countries. The first project step consisted in to identify the electrons accelerator type that in can be constructed in Mexico with the major number of possible equipment, instruments, components and acquisition materials local and useful for the major number of users. the characteristics of the accelerator prototype are: accelerator type transformer with multiple secondary insulated and rectifier circuits with a potential of 0.8 MV of voltage, the second step it consisted in an economic study that permitted to demonstrate the economic feasibility of its construction. (Author)

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

International Nuclear Information System (INIS)

Yotsumoto, Keiichi; Kanazawa, Takao; Haruyama, Yasuyuki; Agematsu, Takashi; Mizuhashi, Kiyoshi; Sunaga, Hiromi; Washino, Masamitsu; Tamura, Naoyuki

1984-02-01

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

Accelerated irradiation growth of zirconium alloys

International Nuclear Information System (INIS)

Griffiths, M.; Gilbert, R.W.; Fidleris, V.

1989-01-01

This paper discusses how sponge zirconium and Zr-2.5 wt% Nb, Zircaloy, or Excel alloys all exhibit accelerated irradiation growth compared with high-purity crystal-bar zirconium for irradiation temperatures between 550 to 710 K and fluences between 0.1 to 10 x 10 25 n · m -2 (E > 1 MeV). There is generally an incubation period or fluence before the onset of accelerated or breakaway growth, which is dependent on the particular material being irradiated, its metallurgical condition before irradiation, and the irradiation temperature. Transmission electron microscopy has shown that there is a correlation between accelerated irradiation growth and the appearance of c-component vacancy loops on basal planes. Measurements in some specimens indicate that a significant fraction of the strain can be directly attributed to the loops themselves. There is considerable evidence to show that their formation is dependent both on the specimen purity and on the irradiation temperature. Materials that have a high interstitial-solute content contain c-component loops and exhibit high growth rates even at low fluences ( 2 :5 n · m -2 , E > 1 MeV). For sponge zirconium and the Zircaloys, c-component loop formation and the associated acceleration of growth (breakaway) during irradiation occurs because the intrinsic interstitial solute (mainly, oxygen, carbon and nitrogen) in the zirconium matrix is supplemented by interstitial iron, chromium, and nickel from the radiation-induced dissolution of precipitates. (author)

Technology and applications of electron accelerator

International Nuclear Information System (INIS)

Natsir, M.

1998-01-01

Technology of electron accelerator have been developed so fast in advanced countries. It was applied in the research and development (R and D) and comercially in various industries. The industries applying electron accelerator includes polymers industry, sterilization of medical tools, material surface modification, and environmental management. The radiation process using electron beam is an ionization radiation process. Two facilities of electron accelerator have been established in pilot scale at the Centre for the Application of Isotope and Radiation CAIR-BATAN, Jakarta, for the RandD of radiation process technology and in demonstrating the electron accelerator application in industry in Indonesia. The first has low energy specification of 300 keV, 50 mA, EPS-300 type and the second has medium energy specification of 2 MeV, 10 mA dynamitron model GJ-2 type. Both the electron accelerators have an electron penetration depth capability of 0.6 and 12 mm, respectively, for the double side irradiation in the materials with density of 1 g/cm 3 . They also highly capacity production and electron beam cross-section of 120 cm length and 10 cm width. The beam will go through the atmosphere for irradiation samples or industrial products. The radiation dose can be selected precisely by adjusting the electron beam current and conveyor speed. Both of these facilities were applied in many aspects RandD, for examples dosimetry, wood surface coating, cross-linking of polymer, heatshrincable tube, polymer grafting, plastic degradation, food preservation, sterilization and so on. Engineering factors of radiation design process and general observation of electron accelerator application in RandD for various industries in Indonesia are briefly discussed

Effects of accelerated electron beam irradiation on surface hardening and fatigue properties in an AISI 4140 steel used for automotive crankshaft

Energy Technology Data Exchange (ETDEWEB)

Choo, S.-H.; Lee, S. [Pohang Univ. of Sci. and Technol. (Korea). Center for Adv. Aerospace Mater.; Golkovski, M.G. [Rossijskaya Akademiya Nauk, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki

2000-11-30

This study is concerned with the effects of high-energy accelerated electron beam irradiation on surface hardening and improvement of fatigue properties in an AISI 4140 steel currently used for automotive crankshaft. The 4140 steel specimens were irradiated in air by using a high-energy electron beam accelerator, and then microstructure, hardness, and fatigue properties were examined. Beam power was varied in the range of 5.2{proportional_to}7.7 kW by changing beam current. Upon irradiation, the unirradiated microstructure containing band structure was changed to martensite and bainite in the carbon-rich zone or ferrite, bainite, and martensite in the carbon-depleted zone. This microstructural modification improved greatly surface hardness and fatigue properties due to transformation of martensite whose amount and type were determined by heat input during irradiation. Thus, high-energy electron beam irradiation can be effectively applied to the surface hardening process of automotive parts. In order to investigate the thermal cycle during electron beam irradiation of quickly rotating specimens, the thermal analysis was also carried out using an analytical computer simulation. Analytical solutions gave information about the peak temperature, heating and cooling rate, and hardened depth to correlate with the overall microstructural modification. (orig.)

Accelerators in industrial electron beam processing

International Nuclear Information System (INIS)

Becker, R.C.

1984-01-01

High power electron beam accelerators are being used for a variety of industrial processes. Such machines can process a wide range of products at very high thruput rates and at very low unit processing costs. These industrial accelerators are now capable of producing up to 200 kW of electron beam power at 4.0 MV and 100 kW at 5.0 MV. At this writing, even larger units are contemplated. The reliability of these high power devices also makes it feasible to consider bremsstrahlung (x-ray) processing as well. In addition to the advance of accelerator technology, microprocessor control systems now provide the capability to coordinate all the operations of the irradiation facility, including the accelerator, the material handling system, the personnel safety system and various auxiliary services. Facility designs can be adapted to many different industrial processes, including use of the dual purpose electron/x-ray accelerator, to ensure satisfactory product treatment with good dose uniformity, high energy efficiency and operational safety and simplicity. In addition, equipment manufacturers like RDI are looking beyond their conventional DC accelerator technology; looking at high power 10-12 MeV linear accelerators with power levels up to 25 kW or more. These high power linear accelerators could be the ideal processing tool for many sterilization and food irradiation applications. (author)

Critical analysis of industrial electron accelerators

Energy Technology Data Exchange (ETDEWEB)

Korenev, S. E-mail: sergey_korenev@steris.com

2004-10-01

The critical analysis of electron linacs for industrial applications (degradation of PTFE, curing of composites, modification of materials, sterilization and others) is considered in this report. Main physical requirements for industrial electron accelerators consist in the variations of beam parameters, such as kinetic energy and beam power. Questions for regulation of these beam parameters are considered. The level of absorbed dose in the irradiated product and throughput determines the main parameters of electron accelerator. The type of ideal electron linac for industrial applications is discussed.

Critical analysis of industrial electron accelerators

Science.gov (United States)

Korenev, S.

2004-09-01

The critical analysis of electron linacs for industrial applications (degradation of PTFE, curing of composites, modification of materials, sterlization and others) is considered in this report. Main physical requirements for industrial electron accelerators consist in the variations of beam parameters, such as kinetic energy and beam power. Questions for regulation of these beam parameters are considered. The level of absorbed dose in the irradiated product and throughput determines the main parameters of electron accelerator. The type of ideal electron linac for industrial applications is discussed.

Critical analysis of industrial electron accelerators

International Nuclear Information System (INIS)

Korenev, S.

2004-01-01

The critical analysis of electron linacs for industrial applications (degradation of PTFE, curing of composites, modification of materials, sterilization and others) is considered in this report. Main physical requirements for industrial electron accelerators consist in the variations of beam parameters, such as kinetic energy and beam power. Questions for regulation of these beam parameters are considered. The level of absorbed dose in the irradiated product and throughput determines the main parameters of electron accelerator. The type of ideal electron linac for industrial applications is discussed

High power pulsed/microwave technologies for electron accelerators vis a vis 10MeV, 10kW electron LINAC for food irradiation at CAT

International Nuclear Information System (INIS)

Shrivastava, Purushottam; Mulchandani, J.; Mohania, P.; Baxy, D.; Wanmode, Y.; Hannurkar, P.R.

2005-01-01

Use of electron accelerators for irradiation of food items is gathering momentum in India. The various technologies for powering the electron LINAC were needed to be developed in the country due to embargo situations as well as reservations of the developers worldwide to share the information related to this development. Centre for Advanced Technology, CAT, Indore, is engaged in the development of particle accelerators for medical industrial and scientific applications. Amongst other electron accelerators developed in CAT, a 10MeV, 10kW LINAC for irradiation of food items has been commissioned and tested for full rated 10kW beam power. The high power pulsed microwave driver for the LINAC was designed, developed and commissioned with full indigenous efforts, and is right now operational at CAT. It consists of a 6MW, 25kW S-band pulsed klystron, 15MW peak power pulse modulator system for the klystron, microwave driver amplifier chain, stabilized generator, protection and control electronics, waveguide system to handle the high peak and average power, gun modulator electronics, grid electronics etc. The present paper highlights various technologies like the pulsed power systems and components, microwave circuits and systems etc. Also the performance results of the high power microwave driver for the 10MeV LINAC at CAT are discussed. Future strategies for developing the state of art technologies are highlighted. (author)

The problems of the usage of powerful electrons accelerators for the irradiation of nuclear power stations' equipment and materials

International Nuclear Information System (INIS)

Kovalinska, T.V.; Khalova, N.V.; Ostapenko, I.A.; Sakhno, V.I.; Zelinsky, A.G.; Shlapatska, V.V.

2012-01-01

The possibilities of making the qualification of the materials and equipment of nuclear power stations on modern electrons accelerators of high power are researched. The problems of using this powerful sources of radiation for modern methods of nondestructive control of functional characteristics of the equipment and materials are discussed. The purpose of researches is the determination of the possibility of such works from the point of view of radiation safety of the personnel and the environment. First of all, this problem is connected with the increase of the intensity of secondary irradiation in such processes. The character of secondary irradiation is researched, as well as the dynamics of its energetic spectrum in rooms of powerful industrial accelerator (with beam power of more than 20 kW and average energy of electrons of 1.6 MeV) in regimes of irradiation of the equipment with contents of heavy elements. The original way of solving this problem is suggested. Experimentally proved, that during the usage of the set of compensatory measures, it is also possible to make tests of NPPs' materials and equipment on industrial accelerators of high power

Electron acceleration by electromagnetic irradiation of a weakly-collisional plasma

International Nuclear Information System (INIS)

Karfidov, D.M.; Lukina, N.A.; Sergeychev, K.F.

1989-01-01

In this paper, electron acceleration is investigated experimentally in both a homogeneous and an inhomogeneous plasma. In the first case acceleration is produced by development of a parametric instability, while in the second case acceleration in a plasma resonance field is used. It is demonstrated that multiple electron passes through a resonant field will produce and accelerated electron energy spectrum characterized by the effective temperature. It is established that the electron replacement current flowing in the interaction region between the plasma and a spatially-limited microwave field excites ion-acoustic turbulence in plasma and also produces an anomalously low thermal conductivity and an anomalously high resistivity

Utilization of 5 MeV electron accelerator center and perspective

International Nuclear Information System (INIS)

Tanaka, Hiromi

1990-01-01

Electron beam process gives instantaneous effect as compared with heating process, and has such merits that energy consumption is very small, objects can be treated from outside, harmful chemicals are not used and treatment can be done as packed. The spread of electron beam process is largely due to the results of the development of highly reliable accelerators and utilization technologies, but as observed from all industrial fields, it is limited to only a part. In order to contribute to the solution of problems and the spread of electron beam process, Sumitomo Heavy Industries, Ltd. installed a 5 MeV, 200 kW large power accelerator developed by RDI in USA in the Electron Irradiation Application and Development Center opened in Tsukuba City. The Center was completed in June, 1989, and has carried out the activities of the development of irradiation utilization technologies, test irradiation and entrusted irradiation service. The features of electron beam process are high dose rate, the possibility of on and off as occasion demands, the preparation of radiation sources and the disposal of wastes being unnecessary, and no environmental problem. The industrialized processes, the types, energy and use of electron accelerators, the Tsukuba irradiation facilities and others are reported. (K.I.)

AECL IMPELA electron beam industrial irradiators

International Nuclear Information System (INIS)

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

1989-01-01

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

Electron accelerators for radiosterilization; Akceleratory elektronow dla potrzeb sterylizacji radiacyjnej

Energy Technology Data Exchange (ETDEWEB)

Zimek, Z [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

1997-10-01

The applications of electron accelerators in commercial plants for radiosterilization have been shown. Advantages of such irradiation source have been presented. The types and parameters of accelerators being installed in worldwide irradiation plants for radiosterilization have been listed as well. 2 tabs.

Economic efficiency analysis of electron accelerator for irradiation processing

International Nuclear Information System (INIS)

Shi Huidong; Chen Ronghui

2003-01-01

The fixed assets, running cost and economic efficiency were discussed in this paper. For building electron accelerator of 10 MeV and 3 kW, the running cost is one time higher than building cobalt source at 2.22 x 10 15 Bq, but economic efficiency of building a electron accelerator is much higher than building a cobalt source

Irradiated accelerated corrosion of stainless steel

International Nuclear Information System (INIS)

Raiman, S.S.; Wang, P.; Was, G.S.

2015-01-01

Type 316L stainless steel was exposed to a simulated PWR environment with in-situ proton irradiation to investigate the effect of simultaneous irradiation and corrosion. To enable these experiments, a dedicated beamline was constructed to transport a 3.2 MeV proton beam from a tandem accelerator, through the sample that also acts as the window between the beamline vacuum and a corrosion cell designed to flow primary water at 320 C. degrees and 13.1 MPa. Experiments were conducted on 316L stainless steel samples which were irradiated for 24 hours in 320 C. degrees water with 3 ppm H 2 , at dose rates of 7*10 -6 dpa/s and 7*10 -7 dpa/s, for 4, 24, and 72 hours. A dual-layer oxide formed on the samples, with an inner layer rich in Cr with Fe and Ni content, and an outer layer of Fe oxides. Samples were characterized with TEM (Transmission Electron Microscopy), EDS, and Raman spectroscopy to determine the effect of irradiation. Irradiated samples were found to have a thinner and more porous inner oxide which was deficient in chromium. The outer oxide was found to have significant hematite content, suggesting that irradiation led to an increase in ECP (Electro-Chemical Potential) at the oxide-solution interface, causing accelerated dissolution of the oxide under irradiation. (authors)

Comparative effectiveness of gamma-rays and electron beams in food irradiation

International Nuclear Information System (INIS)

Hayashi, Toru

1991-01-01

Ionizing radiations which can be used for the treatment of foods are gamma-rays from Co-60 and Cs-137, accelerated electrons from a machine at an energy of 10 MeV or lower and X-rays from a machine at an energy of 5 MeV or lower. The Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food held in 1980 concluded that the foods irradiated at overall average doses up to 10 kGy with the radiation listed above are wholesome for human consumption. While most of the commercial food irradiations are conducted with gamma-rays from Co-60, accelerated electrons are increasingly utilized for treating foods. An important difference between gamma-rays and accelerated electrons is the penetration capacity in materials. The penetration capacity of gamma-rays is much higher than that of accelerated electrons. Another important difference is the dose rate. The dose rates of gamma-rays from commercial Co-60 sources are 1-100 Gy/min, while those of electron beams from electron accelerators are 10 3 -10 6 Gy/s. Ideally a comparison of the effect of different types of ionizing radiation should be carried out at the same dose rate but this has been difficult due to the design of irradiators. It is very difficult to draw a definite conclusion on the difference in the effectiveness in food irradiation between gamma-rays and electron beams based on published data. This chapter deals with as many reports as possible on the comparative effectiveness of gamma-rays and electron beams and on the effect of dose rate on chemical reactions and living organisms, whether or not they demonstrate any dependency of the effect of irradiation on dose rate and type of radiation. (author)

Radiosensitivity of chlorella after medium energy accelerated electron irradiation

International Nuclear Information System (INIS)

Roux, J.C.

1966-06-01

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

Sprout inhibition of potatoes by electron irradiation, (2)

International Nuclear Information System (INIS)

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

1982-01-01

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

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

International Nuclear Information System (INIS)

Feroza Akhtar; Keizo Makuuchi; Fumio Yoshii

1996-01-01

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

Electron accelerators for environmental protection

International Nuclear Information System (INIS)

Zimek, Z.

1998-01-01

The primary objective of this publication is to provide information suitable for electron accelerators implementation in facilities applying radiation technology for environmental protection. It should be noticed that radiation processing has been successfully used in the fields of crosslinking polymer curing and medical products sterilization for more than 40 years. Practical application of radiation technology today extends on SO 2 and NO x removal from the flue gas (one of major power intensive radiation processing), destruction and removal of organic chemicals from water, decreasing bacteria content in the irradiated sludge and waste water. On the other hand the increased awareness of environmental pollution hazards and more stringent waste regulations in many countries may open stronger support for environmentally oriented technologies. This publication provides an evaluation of electron accelerators capabilities in respect of environmental applications where technological and economical criteria are now well defined. In order to determine the potential of electron accelerators, the literature data were examined as well visits and meetings with various accelerator manufacturers were performed by the author. Experience of the author in accelerator facilities construction and exploitation including those which were used for environmental protection are significant part of this publication. The principle of accelerator action was described in Chapter 1. Early development, accelerator classification and fields of accelerators application were included to this chapter as well. Details of accelerator construction was described in Chapter 2 to illustrate physical capability of accelerators to perform the function of ionizing radiation source. Electron beam extraction devices, under beam equipment, electron beam parameters and measuring methods were characterized in this chapter as well. Present studies of accelerator technology was described in Chapter 3, where

Transmission electron microscope interfaced with ion accelerators and its application to materials science

Energy Technology Data Exchange (ETDEWEB)

Abe, Hiroaki; Naramoto, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Hojou, Kiichi; Furuno, Shigemi; Tsukamoto, Tetsuo

1997-03-01

We have developed the transmission/analytical electron microscope interfaced with two sets of ion accelerators (TEM-Accelerators Facility) at JAERI-Takasaki. The facility is expected to provide quantitative insights into radiation effects, such as damage evolution, irradiation-induced phase transformation and their stability, through in-situ observation and analysis under ion and/or electron irradiation. The TEM-Accelerators Facility and its application to materials research are reviewed. (author)

Analytical use of electron accelerators

International Nuclear Information System (INIS)

Kapitsa, S.P.; Chapyzhnikov, B.A.; Firsov, V.I.; Samosyuk, V.N.; Tsipenyuk, Y.M.

1985-01-01

After detailed investigation the authors conclude that the newest electron accelerators provide good scope for gamma activation and also for producing neutrons for neutron activation. These accelerators are simpler and safer than reactors, and one can provide fairly homogeneous irradiation of substantial volumes, and the determination speed and sensitivity then constitute the main advantages. The limits of detection and the reproducibility are sufficient to handle a wide range of tasks. Analysts at present face a wide range of unlikely extreme problems, while the selectivity provides exceptional analysis facilities. However, the record examples are not to be taken as exceptions, since activation analysis based on electron accelerators opens up essentially universal scope for analyzing all elements at the concentrations and accuracies currently involved, which will involve its extensive use in analytical practice in the foreseeable future. The authors indicate that the recognition of these possibilities governs the general use of these methods and the employment of current efficient fast-electron sources to implement them

Electron linear accelerator system for natural rubber vulcanization

Science.gov (United States)

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

2017-09-01

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

Characterization of solvents containing CyMe4-BTPhen in selected cyclohexanone-based diluents after irradiation by accelerated electrons

Czech Academy of Sciences Publication Activity Database

Distler, P.; Kondé, J.; John, J.; Hájková, Zuzana; Švehla, Jaroslav; Grüner, Bohumír

2015-01-01

Roč. 60, č. 4 (2015), s. 885-891 ISSN 0029-5922 R&D Projects: GA MŠk(CZ) 7G13003 EU Projects: European Commission(XE) 323282 - SACSESS Institutional support: RVO:61388980 Keywords : accelerated electrons * CyMe4-BTPhen * irradiation * radiation stability * solvent extraction Subject RIV: CA - Inorganic Chemistry Impact factor: 0.546, year: 2015

Reducing NOx and SOx pollutants in an industrial units using electron accelerator

Directory of Open Access Journals (Sweden)

H Nouri

2017-08-01

Full Text Available Electron beam accelerators technology has made significant progress in environmental applications in recent years. Including some environmental applications of industrial accelerators, is clearing the air from oxides of nitrogen and sulfur(NOx , SOx produced by industrial facilities. Combustion  of coal, oil, natural gas and other gases that are produced in power plant, refineries and industrial factories, produce high extent of these oxides wshich exceed the limit in most cases. Clearing by irradiation involves adding amounts of ammonia to output gases and irradiation by Electron beam accelerators. Irradiation produces radicals that interact again with  NOx , SOx  and produced the related gases. Due to the ammonia, these acids transform into ammonium sulfate ((NH42SO4 and ammonium nitrate (NH4NO3 are precipitated by electrostatic precipitators, and are used as chemical fertilizer. Cosidering purification process of pollutant  gases by electron beam and the importance of electron accelerator in industrial plants that are polluting the environment in Iran, can be a suitable sollution for this environmental problem

The destruction of parasitic resistant stages in sewage sludge by irradiation with low accelerating voltage electrons

International Nuclear Information System (INIS)

Enigk, K.; Holl, P.; Dey-Hazra, A.; Polymer-Physik G.m.b.H. und Co. K.G., Tuebingen

1975-01-01

The destroying effect of ionizing radiation on parasitic resistant stages in sludge has been tested. Suitable for that process is an electron beam accelerator which will be provided with energy from the electric power supply network which can be switched on and off according to the requirements. Such modern utilities have an enormous beam capacity and a high operating safety. The process is working according to the continuous flow principle and at room temperature. In a series of 13 experiments the effect of different doses has been tested. A dose of 480 kRad (accelerating voltage: 400 kV, beam current: 10 mA , irradiation time: 24 sec.) can easily obtained in practical work and is economically acceptable. By these means approximately 97% of the following parasitic stages have been destroyed: undeveloped eggs of Ascaris suum, Trichuris suis, Fasciola hepatica and gastrointestinal strongylids of pigs, embryonated eggs of Capillaria obsignata and probably of Taenia spec. A few third-stage larvae of Oesophagostomum (Strongylidae) of pigs survived even 108 sec of irradiation; however, they did not develop to maturity in the definitive host. Approximately 25% of the sporulated oocysts of Eimeria tenella were still infective after 108 sec of irradiation. (orig.) [de

Radiosensitivity of chlorella after medium energy accelerated electron irradiation; Radiosensibilite des chlorelles aux electrons acceleres de moyenne energie

Energy Technology Data Exchange (ETDEWEB)

Roux, J C [commissariat a L' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1966-06-01

The survival curves (capability of multiplication) of chlorella pyrenoidosa after irradiations can be used for soft electrons (0.65 and 1 MeV), hence penetrating into only 2 to 4 millimeters of water: the algae are laying on porous membranes and the doses are calculated from the power of the electron beam measured by the electric current on a metallic target or by Fricke's dosimetry. With these techniques, it is showed and discussed the part of anoxia in the radioprotection (magnitude or reduction of the dose calculated from the slope of survival curves: 2.5 ) that is more important than the restoration studied by the fractionation of the dose. The 0.65 and 1 MeV electrons have a biologic effect lesser than 180 keV X-rays (RBE - relative biological efficiency - calculated on the slope of survival curves is 0.92 in aerated irradiation, 0.56 in the deoxygenated irradiation). (author) [French] Les courbes de survie clonale (capacite de multiplication) de chlorella pyrenoidosa apres irradiation sont realisables meme avec des electrons peu energetiques (0.65 et 1 MeV), donc peu penetrants, par l'irradiation d'algues deposees sur membrane filtrante et grace au calcul de la dose a partir de l'energie du faisceau mesure par le courant que celui-ci cree dans une cible metallique ou par dosimetrie de Fricke. Par ces techniques, on a montre et discute le role de l'anoxie dans la radioprotection des chlorelles (facteur de reduction de la dose calcule sur la pente des courbes de survie de 2.5) qui est plus important que le pouvoir de restauration etudie par le fractionnement de la dose. Les electrons utilises ont un effet biologique moins grand que les rayons X de 180 keV (l'efficacite biologique relative - EBR - calculee sur la pente des courbes de survie est de 0.9 en presence d'air, 0.6 en presence d'azote)

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

International Nuclear Information System (INIS)

Katsumura, Yosuke

1994-01-01

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

Application of ''elektronika 10-10'' electron linac for food irradiation

International Nuclear Information System (INIS)

Migdal, W.; Maciszewski, W.; Gryzlow, A.

1995-01-01

The industrial electron linac ''Elektronica 10-10'' has been installed in Experimental Plant for Food Irradiation (INCT) in 1990. The accelerator is a prototype unit, prior the use for food treatment a period of optimization was involved in its experimental operation during 1993. The accelerator is capable to produce scanned beam of electrons with the energy 10 MeV and beam power of 10 kW. Radiation dose at minimal conveyer speed of 0.25 m/min reaches 50 kGy. The role of the plant is to promote food irradiation in Poland. (Author)

Evaluation of some commercial grade polymers as possible dosimeters for technological irradiations in electron accelerators

CERN Document Server

Bryl-Sandelewska, T

2002-01-01

Dosimetric properties of two kinds of clear polymethylmethacrylate (PMMA)and one kind of polystyrene (PS) sheets in technological accelerator irradiations, are presented. Absorbance of the sheets and its dependence on the dose have been measured at a suitable wavelength using a UV/VIS spectrophotometer. Both kind PMMA can be used for technological dose measurements but each of them in the different range of the doses (approx 3 to approx 30 kGy and approx 30 to above 200 kGy). Heating the samples after irradiation accelerates the stabilization of the absorbance, which change slowly during the storage of the samples if not heated.Absorbance of clear PS sheets decreases very much during the storage after irradiation, and heating of the samples does not accelerate the stabilization of the value. It can be said that the Ps investigated is not suitable for technological dose measurements in accelerator i radiations.

Evaluation of some commercial grade polymers as possible dosimeters for technological irradiations in electron accelerators

International Nuclear Information System (INIS)

Bryl-Sandelewska, T.; Panta, P.P.

2002-01-01

Dosimetric properties of two kinds of clear polymethylmethacrylate (PMMA)and one kind of polystyrene (PS) sheets in technological accelerator irradiations, are presented. Absorbance of the sheets and its dependence on the dose have been measured at a suitable wavelength using a UV/VIS spectrophotometer. Both kind PMMA can be used for technological dose measurements but each of them in the different range of the doses (∼ 3 to ∼30 kGy and ∼ 30 to above 200 kGy). Heating the samples after irradiation accelerates the stabilization of the absorbance, which change slowly during the storage of the samples if not heated.Absorbance of clear PS sheets decreases very much during the storage after irradiation, and heating of the samples does not accelerate the stabilization of the value. It can be said that the Ps investigated is not suitable for technological dose measurements in accelerator i radiations. (author)

Irradiation-accelerated corrosion of reactor core materials

International Nuclear Information System (INIS)

Bartels, David; Was, Gary; Jiao, Zhijie

2012-09-01

The combination of high temperature, chemically aggressive coolants, a high radiation flux and mechanical stress poses a major challenge for the life extension of current light water reactors, but also applies to most all other GenIV concepts. Of these four drivers, the combination of radiation and corrosion presents a unique and extremely challenging environment for materials, for which an understanding of the fundamental science is essentially absent. Irradiation can affect corrosion or oxidation in at least three different ways. Radiation interaction with water results in the decomposition of water into radicals and oxidizing species that will increase the electrochemical corrosion potential and lead to greater corrosion rates. Irradiation of the solid surface can produce excited states that can alter corrosion, such as in the case of photo-induced corrosion. Lastly, displacement damage in the solid will result in a high flux of defects to the solid-solution interface that can alter and perhaps, accelerate interface reactions. While there exists reasonable understanding of how corrosion is affected by irradiation of the aqueous environment, there is little understanding of how irradiation affects corrosion through its impact on the solid, whether metal or oxide. The reason is largely due to the difficulty of conducting experiments that can measure this effect separately. We have undertaken a project specifically to separate the several effects of irradiation on the mechanisms of corrosion. We seek to answer the question: How does radiation damage to the solution-oxide couple affect the oxidation process differently from radiation damage to either component alone? The approach taken in this work is to closely compare corrosion accelerated by (1) proton irradiation, (2) electron irradiation, and (3) chemical corrosion potential effects alone, under typical PWR operating conditions at 300 deg. C. Both 316 stainless steel and zirconium are to be studied. The proton

Air-electron stream interactions during magnetic resonance IGRT. Skin irradiation outside the treatment field during accelerated partial breast irradiation

International Nuclear Information System (INIS)

Park, Jong Min; Shin, Kyung Hwan; Wu, Hong-Gyun; Kim, Jung-in; Park, So-Yeon; Kim, Jin Ho; Jeon, Seung Hyuck; Choi, Noorie

2018-01-01

To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm 2 , respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field. (orig.) [de

15-year-activity of Electron Linear Accelerator Laboratory

International Nuclear Information System (INIS)

Karolczak, S.

1999-01-01

The purchase of the Russian Electron Linear Accelerator ELU-6E by Institute of Radiation Technique of Lodz Technical University in 1978 started the activity of the ELA Laboratory. The accelerator itself and many additional scientific equipment designed and built during past 15 years have became the basic investigation tool for the ITR now. The most important measuring systems based on electron beam as irradiation source are: pulse radiolysis system with detection in IR, UV and visible region of the spectra, radiation induced conductometry, Faraday chamber and computerized data acquisition and processing system

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

International Nuclear Information System (INIS)

Allen, C.W.

1992-01-01

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

Electron beam irradiation facility for low to high dose irradiation applications

International Nuclear Information System (INIS)

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

2013-01-01

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

Calibration of dosimeters at 80-120 keV electron irradiation

DEFF Research Database (Denmark)

Miller, A.; Helt-Hansen, J.

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

Irradiation-related amorphization and crystallization: In situ transmission electron microscope studies

International Nuclear Information System (INIS)

Allen, C.W.

1994-01-01

Interfacing an ion accelerator to a transmission electron microscope (TEM) allows the analytical functions of TEM imaging and diffraction to be employed during ion-irradiation effects studies. At present there are twelve such installations in Japan, one in France and one in the US. This paper treats several aspects of in situ studies involving electron and ion beam induced and enhanced phase transformations and presents results of several in situ experiments to illustrate the dynamics of this approach in the materials science of irradiation effects. The paper describes the ion- and electron-induced amorphization of CuTi; the ion-irradiation-enhanced transformation of TiCr 2 ; and the ion- and electron-irradiation-enhanced crystallization of CoSi 2

Calorimetry for absorbed dose measurement at 1-4 MeV electron accelerators

International Nuclear Information System (INIS)

Miller, A.

2000-01-01

Calorimeters are used for dose measurement, calibration and intercomparisons at industrial electron accelerators, and their use at 10 MeV electron accelerators is well documented. The work under this research agreement concerns development of calorimeters for use at electron accelerators with energies in the range of 2-4 MeV. The dose range of the calorimeters is 3-40 kGy, and their temperature stability after irradiation was found to be sufficient for practical use in an industrial environment. Measurement uncertainties were determined to be 5% at k = 2. (author)

Dielectric properties of electron irradiated PbZrO 3 thin films

Indian Academy of Sciences (India)

The present paper deals with the study of the effects of electron (8 MeV) irradiation on the dielectric and ferroelectric properties of PbZrO3 thin films grown by sol–gel technique. The films were (0.62 m thick) subjected to electron irradiation using Microtron accelerator (delivered dose 80, 100, 120 kGy). The films were well ...

Air-electron stream interactions during magnetic resonance IGRT : Skin irradiation outside the treatment field during accelerated partial breast irradiation.

Science.gov (United States)

Park, Jong Min; Shin, Kyung Hwan; Kim, Jung-In; Park, So-Yeon; Jeon, Seung Hyuck; Choi, Noorie; Kim, Jin Ho; Wu, Hong-Gyun

2018-01-01

To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm 2 , respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field.

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

International Nuclear Information System (INIS)

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

1996-01-01

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

Practical aspects of the pasteurization of sewage sludge by electron irradiation

International Nuclear Information System (INIS)

Tauber, M.; Hofmann, E.G.; Offermann, B.P.

1975-01-01

Recently the demand for disinfection of sewage sludge has increased. Investigations have shown that the radiation pasteurization of sludge is the most preferable treatment. Up to now most of these investigations have been made with 60 Co radiation sources. However, it is not easy to run an economic and safe process line for the irradiation of sewage sludge with such isotope sources. Powerful electron accelerators are now available and the main features of the irradiation of sewage sludge with fast electrons are discussed and the design parameters of such installations described. From the standpoint of the limited electron penetration into the material it is desirable to use high-energy electrons (up to 1.5 MeV) whereas from an economic standpoint it may be better to use electrons of lower energies (0.5 to 1 MeV) and to homogenize the sewage sludge to the required thickness. The following parameters must be considered for a commercial process line: effectivity of the electron radiation process; limited penetration of electrons into the material to be irradiated; beam power of electron accelerators required for sewage sludge treatment; safety aspects; economics of the process with regard to electron energy, power and homogenization of the material; and environmental aspects of the installations. The practical aspects of commercial process lines for electron irradiation of sewage sludge and the design of handling equipment are discussed in relation to these parameters. (author)

Response of zircon to electron and Ne+ irradiation

International Nuclear Information System (INIS)

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

1997-01-01

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

Polymerization of vinyl stearate multilayers by electron beam irradiation

International Nuclear Information System (INIS)

Nishii, Masanobu; Hatada, Motoyoshi

1975-01-01

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

Radiation Field Forming for Industrial Electron Accelerators Using Rare-Earth Magnetic Materials

Science.gov (United States)

Ermakov, A. N.; Khankin, V. V.; Shvedunov, N. V.; Shvedunov, V. I.; Yurov, D. S.

2016-09-01

The article describes the radiation field forming system for industrial electron accelerators, which would have uniform distribution of linear charge density at the surface of an item being irradiated perpendicular to the direction of its motion. Its main element is non-linear quadrupole lens made with the use of rare-earth magnetic materials. The proposed system has a number of advantages over traditional beam scanning systems that use electromagnets, including easier product irradiation planning, lower instantaneous local dose rate, smaller size, lower cost. Provided are the calculation results for a 10 MeV industrial electron accelerator, as well as measurement results for current distribution in the prototype build based on calculations.

Preparation of PbSe nanoparticles by electron beam irradiation

Indian Academy of Sciences (India)

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

Thermoluminescent characteristics of CaSO4:Dy+PTFE irradiated with high energy electron beams

International Nuclear Information System (INIS)

Alvarez, R.; Rivera, T.; Calderon, J. A.; Jimenez, Y.; Rodriguez, J.; Oviedo, O.; Azorin, J.

2011-10-01

In the present work thermoluminescent response of dysprosium doped calcium sulfate embedded in polytetrafluorethylene (CaSO 4 :Dy+PTFE) under high electron beam irradiations from linear accelerator for clinical applications was investigated. The irradiations were carried out using high electron beams (6 to 18 MeV) from a linear accelerator Varian, C linac 2300C/D, for clinical practice purpose. The electron irradiations were obtained by using the water solid in order to guarantee electronic equilibrium conditions. Field shaping for electron beams was obtained with electron cones. Glow curve and other thermoluminescent characteristics of CaSO 4 :Dy+PTFE were conducted under high electron beams irradiations. The thermoluminescent response of the pellets showed and intensity peak centered at around 235 C. Thermoluminescent response of CaSO 4 :Dy+PTFE as a function of high electron absorbed dose showed a linearity in a wide range. To obtain reproducibility characteristic, a set of pellets were exposed repeatedly for the same electron absorbed dose. The results obtained in this study can suggest the applicability of CaSO 4 :Dy+PTFE pellets for high electron beam dosimetry, provided fading is correctly accounted for. (Author)

Decomposition of PCBs in transformer oil using an electron beam accelerator

Science.gov (United States)

Jung, In-Ha; Lee, Myun-Joo; Mah, Yoon-Jung

2012-07-01

Decomposition of PCBs in commercially used transformer oil used for more than 30 years has been carried out at normal temperature and pressure without any additives using an electron beam accelerator. The experiments were carried out in two ways: batch and continuous pilot plant with 1.5 MeV of energy, a 50 mA current, and 75 kW of power in a commercial scale accelerator. The electron beam irradiation seemed to transform large molecular weight compounds into lower ones, but the impact was considered too small on the physical properties of oil. Residual concentrations of PCBs after irradiation depend on the absorption dose of the electron beam energy, but aliphatic chloride compounds were produced at higher doses of irradiation. As the results from FT-NMR, chloride ions decomposed from the PCBs are likely to react with aliphatic hydro carbon compounds rather than existing as free radical ions in the transformer oil. Since this is a dry process, treated oil can be used as cutting oil or machine oil for heavy equipment without any additional treatments.

Effect of accelerated electron beams on technological properties of ferriquarzites of the Mikhajlovskij ore deposit

International Nuclear Information System (INIS)

Potapov, S.A.; Chakturiya, V.A.; Polyakov, V.A.; Rostovtsev, V.I.

1989-01-01

Method for enrichment of ferruginous quartzites of the Kursk magnetic anomaly, using electron irradiation was tested. Samples were irradiated by 2 MeV accelerated electron beam from IZU-6 industrial accelerator. The absorbed dose was equal to 0.14; 0.40; 0.75 Mrad for different types of quartzites. It is shown that sample irradiation elevates grindability of ferrugineous quartzites of all technological types. Enrichment factors increase. Iron extraction to concentrate grows. Extraction of easily enriched ores increases after irradiation by 2.86 %, quality - by 0.6 %; for oxidized ferruginous quartzites - 3.7 % and 1.5 % respectively. Productivity of grinding process increases 1.8-1.3 times. The described technique is promising and should be introduced possibility of elevating grinding productivity 2.0-2.2 times with increase of technological indices of magnetic separation by 2.5-4.0 % when using more powerful accelerators was established

Outline of irradiation service equipment and properties of its electron beam

International Nuclear Information System (INIS)

Kagehira, K.; Shakudo, T.

2002-01-01

Current ethylene oxide sterilization becomes a subject of discussion on the safety for workers' health. On the other hand, demands for sterilization of disposable health care products and food packaging materials are increasing. On this situation, it is progressing to switch to radiation sterilization witch is easy to adapt to requirements of ISO validation, in particular to electron beam sterilization using electron accelerator, which is safer and easier to control. Our company started electron beam treatment service such as pasteurization, disinfestation, and improvement of polymers as well as sterilization, with introducing a high energy and high power electron accelerator. In this paper, basics of e-beam sterilization, outline of the irradiation service plant and the electron accelerator, and the properties of its electron beam are described. (author)

Study of cell cycle and apoptosis after radiation with electron linear accelerator injury

International Nuclear Information System (INIS)

Xu Lan; Zhou Yinghui; Shi Ning; Peng Miao; Wu Shiliang

2002-01-01

Purpose: To determine the cell cycle and apoptosis of the injured cells after radiation with the electron linear accelerator. Methods: NIH 3T3 cells were irradiated by the radiation with the electron linear accelerator. In the experiment the condition of the cell cycle and apoptosis of the injured cells were measured. The expression of p53 was also tested. Results: After exposure to radiation, the number of apoptotic cells as well as the expression of p53 increased. Conclusion: The electron linear accelerator radiation injury can induce cell apoptosis

Effects of electron beam irradiation on cut flowers and mites

International Nuclear Information System (INIS)

Dohino, Toshiyuki; Tanabe, Kazuo

1994-01-01

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

SU-E-T-124: Anthropomorphic Phantoms for Confirmation of Linear Accelerator Based Small Animal Irradiation

Energy Technology Data Exchange (ETDEWEB)

Perks, J; Benedict, S [UC Davis Cancer Center, Sacramento, CA (United States); Lucero, S [UC Davis, Davis, CA (United States)

2015-06-15

Purpose: To document the support of radiobiological small animal research by a modern radiation oncology facility. This study confirms that a standard, human use linear accelerator can cover the range of experiments called for by researchers performing animal irradiation. A number of representative, anthropomorphic murine phantoms were made. The phantoms confirmed the small field photon and electron beams dosimetry validated the use of the linear accelerator for rodents. Methods: Laser scanning a model, CAD design and 3D printing produced the phantoms. The phantoms were weighed and CT scanned to judge their compatibility to real animals. Phantoms were produced to specifically mimic lung, gut, brain, and othotopic lesion irradiations. Each phantom was irradiated with the same protocol as prescribed to the live animals. Delivered dose was measured with small field ion chambers, MOS/FETs or TLDs. Results: The density of the phantom material compared to density range across the real mice showed that the printed material would yield sufficiently accurate measurements when irradiated. The whole body, lung and gut irradiations were measured within 2% of prescribed doses with A1SL ion chamber. MOSFET measurements of electron irradiations for the orthotopic lesions allowed refinement of the measured small field output factor to better than 2% and validated the immunology experiment of irradiating one lesion and sparing another. Conclusion: Linacs are still useful tools in small animal bio-radiation research. This work demonstrated a strong role for the clinical accelerator in small animal research, facilitating standard whole body dosing as well as conformal treatments down to 1cm field. The accuracy of measured dose, was always within 5%. The electron irradiations of the phantom brain and flank tumors needed adjustment; the anthropomorphic phantoms allowed refinement of the initial output factor measurements for these fields which were made in a large block of solid water.

Electron beam accelerator facilities at IPEN-CNEN/SP

Energy Technology Data Exchange (ETDEWEB)

Somessari, Samir L.; Silveira, Carlos G. da; Paes, Helio; Somessari, Elizabeth S.R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], E-mail: somessar@ipen.br

2007-07-01

Electron beam processing is a manufacturing technique, which applies a focused beam of high-energy electrons produced by an electron accelerator to promote chemical changes within a product. At IPEN-CNEN/SP there are two electron beam accelerators Type Dynamitron{sup R} (manufactured by RDI- Radiation Dynamics Inc.) Job 188 and Job 307 models. The technical specifications for the Job 188 energy 1.5 MeV, beam current 25 mA, scan 1.20 m, beam power 37.5 kW and for the Job 307 energy 1.5 MeV, beam current 65 mA, Scan 1.20 m, beam power 97.5 kW. Some applications of the electron beam accelerator for radiation processing are wire and cable insulation crosslinking, rubber vulcanization, sterilization and disinfection of medical products, food preservation, heat shrinkable products, polymer degradation, aseptic packaging, semiconductors and pollution control. For irradiating these materials at IPEN-CNEN/SP, there are some equipment such as, underbeam capstan with speed control from 10 to 700 m/min; a track; a system to roll up and unroll wires and electric cables, polyethylene blankets and other systems to improve the quality of the products. (author)

Induction linear accelerators for commercial photon irradiation processing

International Nuclear Information System (INIS)

Matthews, S.M.

1989-01-01

A number of proposed irradiation processes requires bulk rather than surface exposure with intense applications of ionizing radiation. Typical examples are irradiation of food packaged into pallet size containers, processing of sewer sludge for recycling as landfill and fertilizer, sterilization of prepackaged medical disposals, treatment of municipal water supplies for pathogen reduction, etc. Volumetric processing of dense, bulky products with ionizing radiation requires high energy photon sources because electrons are not penetrating enough to provide uniform bulk dose deposition in thick, dense samples. Induction Linear Accelerator (ILA) technology developed at the Lawrence Livermore National Laboratory promises to play a key role in providing solutions to this problem. This is discussed in this paper

IMPELA electron accelerators for industrial radiation processing

International Nuclear Information System (INIS)

Hare, G.E.

1990-01-01

IMPELA electron accelerators are derived from a common basic design of rf accelerating structure which is capable of handling beams with powers from 20 to 250 kW at 5 to 18 MeV. A prototype has been built which operates at 50 kW and 10 MeV. The paper describes the major elements of the system with particular reference to features which assist in maintaining irradiation quality, simple operation and high reliability. A cost model based on the prototype is used to demonstrate the economies of scale available and the impact of local prices for utilities. (author)

High brightness electron accelerator

International Nuclear Information System (INIS)

Sheffield, R.L.; Carlsten, B.E.; Young, L.M.

1994-01-01

A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of accelerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity. 5 figs

Outline of irradiation service equipment and properties of its electron beam

Energy Technology Data Exchange (ETDEWEB)

Kagehira, K.; Shakudo, T. [Nuclear Fuel Industries, Ltd., Osaka (Japan)

2002-10-01

Current ethylene oxide sterilization becomes a subject of discussion on the safety for workers' health. On the other hand, demands for sterilization of disposable health care products and food packaging materials are increasing. On this situation, it is progressing to switch to radiation sterilization witch is easy to adapt to requirements of ISO validation, in particular to electron beam sterilization using electron accelerator, which is safer and easier to control. Our company started electron beam treatment service such as pasteurization, disinfestation, and improvement of polymers as well as sterilization, with introducing a high energy and high power electron accelerator. In this paper, basics of e-beam sterilization, outline of the irradiation service plant and the electron accelerator, and the properties of its electron beam are described. (author)

New generation of compact electron accelerators for radiation technologies

International Nuclear Information System (INIS)

Auslender, V.L.; Balakin, V.E.; Kraynov, G.S.

1995-01-01

Compact electron accelerators with energy range 0.25-1.0 MeV and beam power up to 32 kw are described. The feeding high voltage is formed by converter (working frequency 20 khz), coreless step-up transformer and a set of rectifying sections. The rectifying multiplier circuit used in rectifying sections permits to reach voltage gradient along accelerator's axis up to 14 kV/cm. The accelerators with vertical and horizontal position are described. The accelerators can be produced together with local radiation shielding and various underbeam transportation systems for irradiation of different products. Such version can be installed in any room facing general requirements for electric equipment

Design of scan-horn and beam extraction window for a 3 MeV electron accelerator

International Nuclear Information System (INIS)

Ghodke, S.R.; Acharya, S.; Puthran, G.P.; Majumder, R.; Mittal, K.C.; Mahendra Kumar; Sethi, R.C.

2003-01-01

A 3 MeV, 30 kW D.C. electron accelerator is being developed for installation at the Electron Beam Center at Khargar, Navi Mumbai to cater to industrial uses like cable irradiation. This paper describes the design of the scan horn and beam extraction window of this accelerator. (author)

POLYMERS CONTAINING Cu NANOPARTICLES IRRADIATED BY LASER TO ENHANCE THE ION ACCELERATION

Directory of Open Access Journals (Sweden)

Mariapompea Cutroneo

2015-06-01

Full Text Available Target Normal Sheath Acceleration method was employed at PALS to accelerate ions from laser-generated plasma at intensities above 1015 W/cm2. Laser parameters, irradiation conditions and target geometry and composition control the plasma properties and the electric field driving the ion acceleration. Cu nanoparticles deposited on the polymer promote resonant absorption effects increasing the plasma electron density and enhancing the proton acceleration. Protons can be accelerated in forward direction at kinetic energies up to about 3.5 MeV. The optimal target thickness, the maximum acceleration energy and the angular distribution of emitted particles have been measured using ion collectors, X-ray CCD streak camera, SiC detectors and Thomson Parabola Spectrometer.

Performance review of thermionic electron gun developed for RF linear accelerators at RRCAT

International Nuclear Information System (INIS)

Wanmode, Yashwant; Mulchandani, J.; Reddy, T.S.; Bhisikar, A.; Singh, H.G.; Shrivastava, Purushottam

2015-01-01

RRCAT is engaged in development of RF electron linear accelerator for irradiation of industrial and agricultural products. Thermionic electron gun is primary source for this accelerator as beam current in the RF accelerator is modest and thermionic emission is most prevalent option for electron gun development. An electron gun has to meet high cathode emission capability, low filament power, good accessibility for cathode replacement and should provide short time for maintenance. Electron linear accelerator up to beam energy of 10 MeV require electron source of 45-50 keV beam energy and emission current of 1 A. Electron optics of gun and electron beam profile simulations were carried out using CST's particle tracking code and EGUN code. Triode type electron gun of cathode voltage 50 kV pulsed has been designed, developed and integrated with 10 MeV electron linear accelerators at RRCAT. Beam current of more than 600 mA has been measured with faraday cup in the test stand developed for characterizing the electron gun. Two accelerators one is imported and another one developed indigenously has been energized using this electron gun. Beam energy of 5-10 MeV has been achieved with beam current of 250-400 mA by integrating this electron gun with the linear accelerator. This paper reviews the performance of indigenously developed electron gun for both linear accelerators. (author)

Clarification of leachate from reclaimed ground by electron beam irradiation

International Nuclear Information System (INIS)

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

1985-01-01

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

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

International Nuclear Information System (INIS)

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

2004-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2004-10-01

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

Absorption and luminescence of crystalline quartz under electron nanosecond irradiation

Energy Technology Data Exchange (ETDEWEB)

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

1981-02-01

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

Developments of electron accelerators for national economy in the AN SSSR SO IYaF

International Nuclear Information System (INIS)

Auslender, V.L.; Salimov, R.A.

1979-01-01

Described is the work aimed at developing ELV-type electrostatic electron accelerators with electron energies ranging from 0.4 to 1.5 MeV and an average beam current of up to 100 mA, and the ILU-6 electron linear accelerator with the energy from 0.5 to 2 MeV and an average beam current of up to 40 mA. To provide an output of a linearly scanned beam a special titanium window with dimension of 75 x 980 mm which provides transit of a current of up to 80 mA has been developed. To irradiate articles having a cylindrical shape two types of devices with a circular beam scanning have been developed. A device has been worked out for the output of concentrated beams into the atmosphere, in which the electron beam leaves the vacuum through a system of four ports having different diameters. Principles of operation and results of tests of these devices are briefly outlined. Examples of their application are given. More than ten tons of tubes have been irradiated on the ILU-6 accelerator to obtain thermal shrinkage, and this accelerator also served as the basis for developing a radiation sewage treatment plant. An annual economical effect is estimated at 2 million roubles per an accelerator

Charged-particle acceleration through laser irradiation of thin foils at Prague Asterix Laser System

International Nuclear Information System (INIS)

Torrisi, Lorenzo; Cutroneo, Maria; Cavallaro, Salvatore; Musumeci, Paolo; Calcagno, Lucia; Wolowski, Jerzy; Rosinski, Marcin; Zaras-Szydlowska, Agnieszka; Ullschmied, Jiri; Krousky, Eduard; Pfeifer, Miroslav; Skala, Jiri; Velyhan, Andreiy

2014-01-01

Thin foils, 0.5–50 μm in thickness, have been irradiated in vacuum at Prague Asterix Laser System in Prague using 10 15–16  W cm −2 laser intensity, 1315 nm wavelength, 300 ps pulse duration and different focal positions. Produced plasmas from metals and polymers films have been monitored in the forward and backward directions. Ion and electron accelerations have been investigated by using Thomson parabola spectrometer, x-ray streak camera, ion collectors and SiC semiconductor detectors, the latter employed in time-of-flight configuration. Ion acceleration up to about 3 MeV per charge state was measured in the forward direction. Ion and electron emissions were detected at different angles as a function of the irradiation conditions. (paper)

Electron acceleration via high contrast laser interacting with submicron clusters

International Nuclear Information System (INIS)

Zhang Lu; Chen Liming; Wang Weiming; Yan Wenchao; Yuan Dawei; Mao Jingyi; Wang Zhaohua; Liu Cheng; Shen Zhongwei; Li Yutong; Dong Quanli; Lu Xin; Ma Jinglong; Wei Zhiyi; Faenov, Anatoly; Pikuz, Tatiana; Li Dazhang; Sheng Zhengming; Zhang Jie

2012-01-01

We experimentally investigated electron acceleration from submicron size argon clusters-gas target irradiated by a 100 fs, 10 TW laser pulses having a high-contrast. Electron beams are observed in the longitudinal and transverse directions to the laser propagation. The measured energy of the longitudinal electron reaches 600 MeV and the charge of the electron beam in the transverse direction is more than 3 nC. A two-dimensional particle-in-cell simulation of the interaction has been performed and it shows an enhancement of electron charge by using the cluster-gas target.

Electron accelerator

International Nuclear Information System (INIS)

Abramyan.

1981-01-01

The USSR produces an electron accelerator family of a simple design powered straight from the mains. The specifications are given of accelerators ELITA-400, ELITA-3, ELT-2, TEUS-3 and RIUS-5 with maximum electron energies of 0.3 to 5 MeV, a mean power of 10 to 70 kW operating in both the pulsed and the continuous (TEUS-3) modes. Pulsed accelerators ELITA-400 and ELITA-3 and RIUS-5 in which TESLA resonance transformers are used are characterized by their compact size. (Ha)

Behaviour of some fresh fruits under electron-beam irradiation

International Nuclear Information System (INIS)

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

1994-01-01

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

Electron beam irradiation of simulated diluted sulfurous off-gases from copper smelters

International Nuclear Information System (INIS)

Villanueva, L.; Ahumada, L.; Chmielewski, A.G.; Zimek, Z.; Bulka, S.; Licki, J.

1998-01-01

An experimental work for the verification of potential use of electron-beam irradiation processing for S O 2 removal from reduced-S O 2 -strength gases, between 1,000 and 10,000 ppm, was conducted in a laboratory unit equipped with a multi-purpose electron accelerator working with beam energy of 800 keV. During experimental tests performed, influence of different operating parameters on the overall S O 2 removal process was established. Tests were conducted under two main conditions, using only electron beam irradiation and using electron beam irradiation plus ammonia injection. Tests results proved the technical feasibility to move S O 2 from off-gases under working experimental conditions, i.e., S O 2 removal is achieved under the two modes of operation. When using only electron beam irradiation S O 2 removal efficiencies found were rather low, up to 40%, but in the case of using electron beam irradiation in conjunction with ammonia injection, it was found that S O 2 removal efficiency raises up to 85% under experimental conditions. (author)

Treatment of toxic gases SO2 and NO X by electron beam irradiation

International Nuclear Information System (INIS)

Castro Rubio Poli, D. de; Vieira, J.M.; Campos, C.A. de.

1993-01-01

The removal of S O 2 and N O x by electron beam irradiation will be studied using a small scale flow system which is being set up in order to obtain basic data for the process technical and economical feasibility concerning industrial applications. The gas irradiation will be performed using a Electron Beam Accelerator with 1,5 MeV power, 25 m A current from Radiation Dynamics, Inc. USA. (author)

Modernization of electron accelerator on the base of the RUP-400 x-ray unit

International Nuclear Information System (INIS)

Buslaev, I.I.; Kon'kov, N.G.; Kochetov, O.N.; Krylov, S.Yu.; Nikolaev, S.M.

1976-01-01

A device has been designed enabling one to change directly from the control panel relation of high to low energy electrons in the beam with a view to up-date a linear electron accelerator. The device comprises a high-voltage transformer accommodating an accelerating tube of the vacuum system with a titanium pump and a scanner. 1.5 BPV-2-400 X-ray tube with a renewable cathode is used as an accelerating tube. As a result of these modifications the accelerator has become smaller and not so heavy. Its characteristics on material irradiation have also improved

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

Directory of Open Access Journals (Sweden)

Abbas Behjat

2007-03-01

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

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

International Nuclear Information System (INIS)

Gavrila, L.; Usurelu, D.; Radu, I.; Timus, D.

2005-01-01

A broad spectrum of chromosomal rearrangements is described in plants (Allium cepa), mouse (Mus musculus domestics) and in humans (Homo sapiens sapiens), following in vivo and in vitro beta irradiation. Irradiations were performed at EAL, using a 2.998 GHz traveling-wave electron accelerator. The primary effect of electron beam irradiation is chromosomal breakage followed up by a variety of chromosomal rearrangements i.e. chromosomal aberrations represented mainly by chromatid gaps, deletions, ring chromosomes, dicentrics, translocations, complex chromosomal interchanges, acentric fragments and double minutes (DM). The clastogenic effects were associated in some instances with cell sterilization (i.e. cell death)

Intensive beam dosimetry of accelerated electrons of low energy

International Nuclear Information System (INIS)

Oproiu, C.

1984-01-01

Dosimetric control of electron beams ranging between 0.3 MeV and 10 MeV is treated using proper dosimetric methods relying on calorimetry, Tricke chemical solution, dosimetric film of cellulose triacetate. Proper methods are pointed out for measurements in inhomogeneous fields, bringing into evidence the results obtained in deep dose distributions and on the surface of irradiated material. A measuring method of dose distribution in depth by means of an assembly with calorimetric elements, as well as a practical method to pointing out dose distribution and equidose curves along the depth of irradiated electric cable depth are presented. In order to find out the main sizes of accelerated electron beam one uses proper devices relying on Faraday cylinder, total absorption calorimeter, ionization chambers. (author)

Polymeric materials obtained by electron beam irradiation

International Nuclear Information System (INIS)

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

1995-01-01

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

Stress relaxation under cyclic electron irradiation

International Nuclear Information System (INIS)

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

1990-01-01

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

Preliminary research concerning the use of electron accelerators to improve the conservability and to extend the shelf-life of fruits and vegetables

International Nuclear Information System (INIS)

Minea, R.

1996-01-01

The potential of ionizing radiation treatment for food preservation, shelf-life extension, control of microbial load and reduction of pathogenic microorganism was demonstrated. The irradiations were performed under normal conditions on the Institute of Physics and Technology for Radiation Device's linear electron accelerator, which has the following parameters: 5 μA mean beam current, 6 MeV electron mean energy, pulse period 3.5 μs and dose rates between 100-1500 Gy/min. This research project was aimed at assuring the consumer's acceptance for radiation-treated food and to obtain a significant reduction of food losses. We also propose a promising solution for the radiation processing of some bulk food products at the place of storage, consisting of a mobile electron accelerator. The main characteristics of the mobile electron accelerator are: electron energy 3 to 5 MeV, maximum beam power 5 kW, vertical electron beam; irradiation is possible both with electron beams and with bremsstrahlung. The results of our preliminary research lead to the conclusion that electron-beam irradiation and the use of electron accelerators is a promising solution for food preservation and food safety. Interesting future applications are outlined. (orig.)

The use of low energy electron accelerator for processing of liquid matter in Indonesia

International Nuclear Information System (INIS)

Danu, Sugiarto

2003-01-01

Activities of radiation processing in Indonesia covering various fields are reviewed. The low and medium energy electron accelerator specially designed for radiation processing of liquid materials is introduced. P3TIR-BATAN is mostly engaged in radiation processing in general with Co-60 source and electron accelerators (300 keV, 50 mA and 2 MeV, 10 mA). A private company, Gajah Tunggal, has an accelerator of 500 keV, 20 mA. The use of low energy electron accelerator to irradiate liquid matter matter such as natural rubber latex, polysaccharides, starch, chitosan and other natural polymers in Indonesia are reported and future program of national research cooperation between government institutions and private companies are described. (S. Ohno)

Sterilizing effect of irradiation for Zuogui power with electron beam and γ-rays

International Nuclear Information System (INIS)

Yue Ling; Kong Qiulian; Qi Wenyuan; Bao Yingzi; Chen Zhijun; Yuan Zhongyi

2011-01-01

The sterilizing effect of irradiation for Zuogui powder with accelerator (electron beam) and a cobalt unit (γ-rays) was studied. The results indicated that the D 10 values of E-beam irradiation and γ-rays irradiation were 2.602 kGy and 2.597 kGy for aerobic bacterial count, while those were 3.112 kGy and 3.208 kGy for mould and yeasts. (authors)

7.5 MeV High Average Power Linear Accelerator System for Food Irradiation Applications

International Nuclear Information System (INIS)

Eichenberger, Carl; Palmer, Dennis; Wong, Sik-Lam; Robison, Greg; Miller, Bruce; Shimer, Daniel

2005-09-01

In December 2004 the US Food and Drug Administration (FDA) approved the use of 7.5 MeV X-rays for irradiation of food products. The increased efficiency for treatment at 7.5 MeV (versus the previous maximum allowable X-ray energy of 5 MeV) will have a significant impact on processing rates and, therefore, reduce the per-package cost of irradiation using X-rays. Titan Pulse Sciences Division is developing a new food irradiation system based on this ruling. The irradiation system incorporates a 7.5 MeV electron linear accelerator (linac) that is capable of 100 kW average power. A tantalum converter is positioned close to the exit window of the scan horn. The linac is an RF standing waveguide structure based on a 5 MeV accelerator that is used for X-ray processing of food products. The linac is powered by a 1300 MHz (L-Band) klystron tube. The electrical drive for the klystron is a solid state modulator that uses inductive energy store and solid-state opening switches. The system is designed to operate 7000 hours per year. Keywords: Rf Accelerator, Solid state modulator, X-ray processing

Shielding Calculations for Industrial 5/7.5MeV Electron Accelerators Using the MCNP Monte Carlo Code

International Nuclear Information System (INIS)

Peri, E.; Orion, I.

2014-01-01

High energy X-rays from accelerators are used to irradiate food ingredients to prevent growth and development of unwanted biological organisms in food, in order to extend the shelf life of products. High energy photons can cause food activation due to (D 3 ,n) reactions. Until 2004, to eliminate the possibility of food activation, the electron energy was limited to 5 MeV X-rays for food irradiation. In 2004, the FDA approved the usage of up to 7.5 MeV, but only with tantalum and gold targets (1). Higher X-ray energy results an increased flux of X-rays in the forward direction, increased penetration, and higher photon dose rate due to better electron-to-photon conversion. These improvements could decrease the irradiation time and allow irradiation of larger packages, thereby providing higher production rates with lower treatment cost. Medical accelerators usually work with 6-18 MV electron energy with tungsten target to convert the electron beam to X-rays. In order to protect the patients, the accelerator head is protected with a heavy lead shielding; therefore, the bremsstrahlung is emitted only in the forward direction. There are many publications and standards that guide how to design optimal shielding for medical accelerator rooms. The shielding data for medical accelerators is not applicable for industrial accelerators, since the data is for different conversion targets, different X-Ray energies, and only for the forward direction. Collimators are not always in use in industrial accelerators, and therefore bremsstrahlung photons can be emitted in all directions. The bremsstrahlung spectrum and dose rate change as a function of the emission angle. The dose rate decreases from maximum in the forward direction (0°) to minimum at 180° by 1-2 orders of magnitude. In order to design and calculate optimal shielding for food accelerator rooms, there is a need to have the bremsstrahlung spectrum data, dose rates and concrete attenuation data in all emission directions

Decomposition of PCBs in transformer oil using an electron beam accelerator

International Nuclear Information System (INIS)

Jung, In-Ha; Lee, Myun-Joo; Mah, Yoon-Jung

2012-01-01

Decomposition of PCBs in commercially used transformer oil used for more than 30 years has been carried out at normal temperature and pressure without any additives using an electron beam accelerator. The experiments were carried out in two ways: batch and continuous pilot plant with 1.5 MeV of energy, a 50 mA current, and 75 kW of power in a commercial scale accelerator. The electron beam irradiation seemed to transform large molecular weight compounds into lower ones, but the impact was considered too small on the physical properties of oil. Residual concentrations of PCBs after irradiation depend on the absorption dose of the electron beam energy, but aliphatic chloride compounds were produced at higher doses of irradiation. As the results from FT-NMR, chloride ions decomposed from the PCBs are likely to react with aliphatic hydro carbon compounds rather than existing as free radical ions in the transformer oil. Since this is a dry process, treated oil can be used as cutting oil or machine oil for heavy equipment without any additional treatments. - Highlights: ► We developed a novel technology of decomposing PCBs in transformer oil using an electron beam. ► Distinct feature is accomplishing at ambient temperature and pressure without any additives. ► Residual PCBs were depended on absorption dose, but aliphatic chlorides were produced at higher dose. ► Treated oil can be reused as heating oil with chlorine removal technology developed here.

Dedicated Tool for Irradiation and Electrical Measurement of Large Surface Samples on the Beamline of a 2.5 Mev Pelletron Electron Accelerator: Application to Solar Cells

OpenAIRE

Lefèvre Jérémie; Le Houedec Patrice; Losco Jérôme; Cavani Olivier; Boizot Bruno

2017-01-01

We designed a tool allowing irradiation of large samples over a surface of A5 size dimension by means of a 2.5 MeV Pelletron electron accelerator. in situ electrical measurements (I-V, conductivity, etc.) can also be performed, in the dark or under illumination, to study radiation effects in materials. Irradiations and electrical measurements are achievable over a temperature range from 100 K to 300 K. The setup was initially developed to test real-size triple junction solar cells at low t...

80 A/cm2 electron beams from metal targets irradiated by KrCl and XeCl excimer lasers

Science.gov (United States)

Beloglazov, A.; Martino, M.; Nassisi, V.

1996-05-01

Due to the growing demand for high-current and long-duration electron-beam devices, laser electron sources were investigated in our laboratory. Experiments on electron-beam generation and propagation from aluminium and copper targets illuminated by XeCl (308 nm) and KrCl (222 nm) excimer lasers, were carried out under plasma ignition due to laser irradiation. This plasma supplied a spontaneous accelerating electric field of about 370 kV/m without an external accelerating voltage. By applying the modified one-dimensional Poisson equation, we computed the expected current and we also estimated the plasma concentration during the accelerating process. At 40 kV of accelerating voltage, an output current pulse of about 80 A/cm2 was detected from an Al target irradiated by the shorter wavelength laser.

On-site installation and shielding of a mobile electron accelerator for radiation processing

International Nuclear Information System (INIS)

Catana, D.; Panaitescu, J.; Axinescu, S.; Manolache, D.; Matei, C.; Corcodel, C.; Ulmeanu, M..; Bestea, V.

1995-01-01

The development of radiation processing of some bulk products, e.g. grains or potatoes, would be sustained if the irradiation had been carried out at the place of storage, i.e. silo. A promising solution is proposed consisting of a mobile electron accelerator, installed on a couple of trucks and traveling from one customer to another. The energy of the accelerated electrons was chosen at 5 MeV, with 10 to 50 kW beam power. The irradiation is possible either with electrons or with bremsstrahlung. A major problem of the above solution is the provision of adequate shielding at the customer, with a minimum investment cost. Plans for a bunker are presented, which houses the truck carrying the radiation head. The beam is vertical downwards, through the truck floor, through a transport pipe and a scanning horn. The irradiation takes place in a pit, where the products are transported through a belt. The belt path is so chosen as to minimize openings in the shielding. Shielding calculations are presented supposing a working regime with 5 MeV bremsstrahlung. Leakage and scattered radiation are taken into account. (orig.)

On-site installation and shielding of a mobile electron accelerator for radiation processing

Energy Technology Data Exchange (ETDEWEB)

Catana, D. [Institutul de Fizica Atomica, Bucharest (Romania); Panaitescu, J. [Institutul de Fizica Atomica, Bucharest (Romania); Axinescu, S. [Institutul de Fizica Atomica, Bucharest (Romania); Manolache, D. [Institutul de Fizica Atomica, Bucharest (Romania); Matei, C. [Institutul de Fizica Atomica, Bucharest (Romania); Corcodel, C. [Institutul de Fizica Atomica, Bucharest (Romania); Ulmeanu, M.. [Institutul de Fizica Atomica, Bucharest (Romania); Bestea, V. [Institutul de Fizica Atomica, Bucharest (Romania)

1995-05-01

The development of radiation processing of some bulk products, e.g. grains or potatoes, would be sustained if the irradiation had been carried out at the place of storage, i.e. silo. A promising solution is proposed consisting of a mobile electron accelerator, installed on a couple of trucks and traveling from one customer to another. The energy of the accelerated electrons was chosen at 5 MeV, with 10 to 50 kW beam power. The irradiation is possible either with electrons or with bremsstrahlung. A major problem of the above solution is the provision of adequate shielding at the customer, with a minimum investment cost. Plans for a bunker are presented, which houses the truck carrying the radiation head. The beam is vertical downwards, through the truck floor, through a transport pipe and a scanning horn. The irradiation takes place in a pit, where the products are transported through a belt. The belt path is so chosen as to minimize openings in the shielding. Shielding calculations are presented supposing a working regime with 5 MeV bremsstrahlung. Leakage and scattered radiation are taken into account. (orig.).

Construction of an electron accelerator of 20 KeV: application in the polymeric study

International Nuclear Information System (INIS)

Sandonato, G.M.

1983-01-01

A low energy electron accelerator (maximum energy 20 KeV) is constructed. A black and white kinescope electron gun, with a single thermionic emitter was used as electron source. The energy of electron beam can be changed continuously from 0 to 20 KeV. The intensity of the current can be changed from a minimum of 10 -12 A to a maximum of 3 μA, and can be mantained contant in time after its value has been fixed. The irradiated area can be changed from a diameter of 1 milimeter to a maximum of 6 centimeter, by focalizing or defocalizing the image of electron beam. The final pressure reached in vacuum chambers was 10 -7 Torr. During operation the surface of cathode of electron gun is damaged by ion bombardeament. The degree of damage can be checked if the cathode image is focalized and examined on a luminescent screen. The accelerator was used to study electron irradiation effects in Teflon, employing the method of the split Faraday cup. Transient charging and discharging currents were measured. The average range of electrons of the electrons and the induced conductivity were determined. (Author) [pt

A variable electron beam and its irradiation effect on optical and ...

Indian Academy of Sciences (India)

A low energy electron accelerator has been constructed and tested. The electron beam can operate in low energy mode (100 eV to 10 keV) having a beam diameter of 8–10 mm. Thin films of CdS having thickness of 100 nm deposited on ITO-coated glass substrate by thermal evaporation method have been irradiated by ...

Photo-production of (99)Mo/(99m)Tc with electron linear accelerator beam.

Science.gov (United States)

Avagyan, R; Avetisyan, A; Kerobyan, I; Dallakyan, R

2014-09-01

We report on the development of a relatively new method for the production of (99)Mo/(99m)Tc. The method involves the irradiation of natural molybdenum using high-intensity bremsstrahlung photons from the electron beam of the LUE50 linear electron accelerator located at the Yerevan Physics Institute (YerPhi). The production method has been developed and shown to be successful. The linear electron accelerator at YerPhi was upgraded to allow for significant increases of the beam intensity and spatial density. The LUE50 was also instrumented by a remote control system for ease of operation. We have developed and tested the (99m)Tc extraction from the irradiation of natural MoO3. This paper reports on the optimal conditions of our method of (99)Mo production. We show the success of this method with the production and separation of the first usable amounts of (99m)Tc. Copyright © 2014 Elsevier Inc. All rights reserved.

Dual ion beam irradiation system for in situ observation with electron microscope

International Nuclear Information System (INIS)

Tsukamoto, Tetuo; Hojou, Kiiti; Furuno, Sigemi; Otsu, Hitosi; Izui, Kazuhiko.

1993-01-01

We have developed a new in situ observation system for dynamic processes under dual ion beam irradiation. The system consists of a modified 400 keV analytical electron microscope (JEOL, JEM-4000FX) and two 40 kV ion beam accelerators. This system allows evaluation of microscopic changes of structure and chemical bonding state of materials in the dynamic processes under two kinds of ion beam irradiations, that is required for the simulation test of the first wall of nuclear fusion reactors onto which He + , H + , and H 2 + ions are irradiated simultaneously. These two ion accelerators were equipped symmetrically both sides of the electron microscope and individually controlled. Each ion beam extracted from a duo-plasmatron ion gun is bent downward by an angle of 30deg with a mass-separating magnet, and introduced into specimen chamber of the electron microscope. Inside the specimen chamber the beam is deflected again by an angle of 30deg with an electrostatic prism so as to be incident on the specimen surface. Finally, two ion beams from both side are incident on the specimen surface at an angle of 60deg. The maximum ion current density of helium is more than 250μA/cm 2 at the specimen at an ion energy of 17 keV. Images of the electron microscope during dual ion beam irradiation are observed through a TV camera and recorded with a VTR. (author)

Electron accelerators for radiation processing: Criterions of selection and exploitation

International Nuclear Information System (INIS)

Zimek, Zbigniew

2001-01-01

The progress in accelerator technology is tightly attached to the continuously advanced development in many branches of technical activity. Although the present level of accelerators development can satisfy most of the commercial requirements, this field continues to expand and improve quality by offering efficient, cheap, reliable, high average beam power commercial units. Accelerator construction must be a compromised between size, efficiency and cost with respect to the field of its application. High power accelerators have been developed to meet specific demands of flue gas treatment and other high throughput to increase the capacity of the progress and reduced unit cost of operation. Automatic control, reliability and reduced maintenance, adequate adoption to process conditions, suitable electron energy and beam power are the basic features of modern accelerator construction. Accelerators have the potential to serve as industrial radiation sources and eventually may replace the isotope sources in future. Electron beam plants can transfer much higher amounts of energy into the irradiated objects than other types of facilities including gamma plants. This provides the opportunity to construct technological lines with high capacity that are more technically and economically suitable with high throughputs, short evidence time and grate versatility

The auroral electron accelerator

International Nuclear Information System (INIS)

Bryant, D.A.; Hall, D.S.

1989-01-01

A model of the auroral electron acceleration process is presented in which the electrons are accelerated resonantly by lower-hybrid waves. The essentially stochastic acceleration process is approximated for the purposes of computation by a deterministic model involving an empirically derived energy transfer function. The empirical function, which is consistent with all that is known of electron energization by lower-hybrid waves, allows many, possibly all, observed features of the electron distribution to be reproduced. It is suggested that the process occurs widely in both space and laboratory plasmas. (author)

Dose-effect curves for electron-beam irradiation of some collection microbial strains

International Nuclear Information System (INIS)

Ferdes, O.; Dumitru, E.; Catargiu, L.; Ferdes, M.; Minea, R.; Oproiu, C.; Niculescu, A.

1994-01-01

There were electron-beam irradiated some microbial strains of B.subtilis ICA I-60 both in germination and in sporulated forms. The irradiation were performed at the IPTRD's electron accelerator at 6 MeV, and in the dose range between 0.1-5.0 kGy, at different dose-rate varying from 50 Gy/minute to 100 Gy/minute. The dosimetry was carried out by a PTW medical dosemeter. There were established the dose-effect relationships and curves, the inactivation dose (factor) and the optimum domain for electron-beam mutagenesis. There were obtained some mutant strains with 2-3.5 higher biosynthesis potential, which are in the IFC's collection. (Author)

Acceleration of electrons using an inverse free electron laser auto- accelerator

International Nuclear Information System (INIS)

Wernick, I.K.; Marshall, T.C.

1992-07-01

We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW's) FEL radiation at ∼1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of the electrons are accelerated to energies as high as 1100 keV, in accordance with predictions from the numerical model. The appearance of high energy electrons is correlated with the abrupt absorption of millimeter power. The autoaccelerator configuration is used because there is no intense source of coherent power at the 1.65 mm design wavelength other than the FEL

Electron accelerators and nanomaterials - a symbiosis

International Nuclear Information System (INIS)

Dixit, Kavita P.; Mittal, K.C.

2011-01-01

Electron Accelerators and Nanomaterials share a symbiotic relationship. While electron accelerators are fast emerging as popular tools in the field of nanomaterials, use of nanomaterials so developed for sub-systems of accelerators is being explored. Material damage studies, surface modification and lithography in the nanometre scale are some of the areas in which electron accelerators are being extensively used. New methods to characterize the structure of nanoparticles use intense X-ray sources, generated from electron accelerators. Enhancement of field emission properties of carbon nanotubes using electron accelerators is another important area that is being investigated. Research on nanomaterials for use in the field of accelerators is still in the laboratory stage. Yet, new trends and emerging technologies can effectively produce materials which can be of significant use in accelerators. Properties such as enhanced field emission can be put to use in cathodes of electron guns. Superconducting properties some materials may also be useful in accelerators. This paper focusses on the electron accelerators used for synthesis, characterization and property-enhancement of nanomaterials. The details of electron accelerators used for these applications will be highlighted. Some light will be thrown on properties of nano materials which can have potential use in accelerators. (author)

Microbiological decontamination of Spirulina Platensis and green coffee using accelerated electron beams

International Nuclear Information System (INIS)

Nemtanu, Monica R.; Brasoveanu, Mirela; Minea, R.; Mitru, Ecaterina; Grecu, Maria Nicoleta; Albulescu, Mihaela

2006-01-01

Biological raw materials can be contaminated with microorganisms and to make them suitable for commercialization, the quality relative to microbial content is necessary to be achieved. Irradiation is a decontamination method for numerous foodstuffs, being a feasible, very effective and environment friendly procedure. The aim of the paper is to evaluate the possibility to apply the electron beam treatment on Spirulina Platensis and green coffee for biological decontamination. The cyanobacterium Spirulina and green coffee have been irradiated with electron beams up to 40 kGy. To determine the microbial load, antioxidant activity, and rheological behaviour the techniques of electron paramagnetic resonance (EPR) and absorption spectroscopy have been applied. The results showed that accelerated electron beams could be efficient to decontaminate Spirulina as well as green coffee without significant changes in their properties. (authors)

1-Chloronaphthalene decomposition in air using electron beam irradiation

International Nuclear Information System (INIS)

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

2006-01-01

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

An electron beam irradiation method for modification of surface electrical resistivity of polyamides

International Nuclear Information System (INIS)

Brasoveanu, M. M.; Timus, D.; Nemtanu, M. R.

2002-01-01

The synthetic textiles which have mechanical and processing properties and a low price are very useful and consequently in high demand. The low antistatic qualities are an important disadvantage, but not impossible to eliminate. The aim of paper is the study of modification the antistatic properties of polyamide by grafting of monomers by irradiation. Twisted and unthermofixed polyamide-6 fibre from CFS Savinesti were investigated. The samples of polyamide were irradiated with an electron beam from the ALIN-7 linear accelerator of Electron Accelerators Laboratory of National Institute for Lasers, Plasma and Radiation Physics, Bucharest. Immediately after irradiation, the samples were measured by electron spin resonance (ESR). ESR spectra were recorded at room temperature using a Jeol spectrometer, JES-ME-3X, with 100 kHz modulation. In polyamide-6 at least two irradiation defect types occurred which present EPR signal by electron beam irradiation. Unstable centres of type A presenting an incompletely resolved hyperfine structure can be attributed to radicals -N-CH 2 - or -NH-CH-CH 2 -. Both radicals can present at room temperature a five-line spectrum like the radical formed in this work. First radical appears with very low probability and if the free bond is at one of carbon atoms then it will be stabilized immediately in a position from nitrogen. These type A radicals can appear in same zone and then they can react and form unsaturated bonds or bridge between the polymeric chains. Thus, it will appear the type B defects which were more stabile and without structure. On these double chains one can graft vinylic monomers even after time intervals longer from irradiation. (authors)

Apparatus for irradiation with electron beam

International Nuclear Information System (INIS)

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

1976-01-01

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

Method for pulse to pulse dose reproducibility applied to electron linear accelerators

International Nuclear Information System (INIS)

Ighigeanu, D.; Martin, D.; Oproiu, C.; Cirstea, E.; Craciun, G.

2002-01-01

An original method for obtaining programmed beam single shots and pulse trains with programmed pulse number, pulse repetition frequency, pulse duration and pulse dose is presented. It is particularly useful for automatic control of absorbed dose rate level, irradiation process control as well as in pulse radiolysis studies, single pulse dose measurement or for research experiments where pulse-to-pulse dose reproducibility is required. This method is applied to the electron linear accelerators, ALIN-10 of 6.23 MeV and 82 W and ALID-7, of 5.5 MeV and 670 W, built in NILPRP. In order to implement this method, the accelerator triggering system (ATS) consists of two branches: the gun branch and the magnetron branch. ATS, which synchronizes all the system units, delivers trigger pulses at a programmed repetition rate (up to 250 pulses/s) to the gun (80 kV, 10 A and 4 ms) and magnetron (45 kV, 100 A, and 4 ms).The accelerated electron beam existence is determined by the electron gun and magnetron pulses overlapping. The method consists in controlling the overlapping of pulses in order to deliver the beam in the desired sequence. This control is implemented by a discrete pulse position modulation of gun and/or magnetron pulses. The instabilities of the gun and magnetron transient regimes are avoided by operating the accelerator with no accelerated beam for a certain time. At the operator 'beam start' command, the ATS controls electron gun and magnetron pulses overlapping and the linac beam is generated. The pulse-to-pulse absorbed dose variation is thus considerably reduced. Programmed absorbed dose, irradiation time, beam pulse number or other external events may interrupt the coincidence between the gun and magnetron pulses. Slow absorbed dose variation is compensated by the control of the pulse duration and repetition frequency. Two methods are reported in the electron linear accelerators' development for obtaining the pulse to pulse dose reproducibility: the method

Dose response of thin-film dosimeters irradiated with 80-120 keV electrons

DEFF Research Database (Denmark)

Helt-Hansen, J.; Miller, A.; Sharpe, P.

2005-01-01

Thin-film dosimeters (Riso B3 and alanine films) were irradiated at 10 MeV and 80-120 keV electron accelerators, and it has been shown that the radiation response of the dosimeter materials (the radiation chemical yields) are constant at these irradiation energies. However, dose gradients within ...... are present within the dosimeter. (C) 2005 Elsevier Ltd. All rights reserved....

Pre-feasibility study of electron beam irradiation of fresh water

International Nuclear Information System (INIS)

Finshi V, Silvia.

1997-01-01

A technical/economic evaluation of electron beam irradiation for the decontamination of liquids in the country is presented. Irradiation of fresh water is evaluated for the production of drinking water as a replacement for chlorine disinfection, which can lead to the formation of tri halo methanes. that are carcinogenic compounds. The technical literature states that the percentage of microorganisms removed by electro beam irradiation is high and similar to that found with chlorine disinfection. From an economic point of view, irradiation technology is not presently competitive as an alternative to conventional chlorination in terms of processing costs (US$0.23/m 3 ) instead of US$0.013/m 3 for conventional chlorination. Nevertheless, irradiation costs decreased sharply when unit costs for the accelerator machine are decreased with a resulting drop in capital costs

Acceleration of laser-injected electron beams in an electron-beam driven plasma wakefield accelerator

International Nuclear Information System (INIS)

Knetsch, Alexander

2018-03-01

Plasma wakefields deliver accelerating fields that are approximately a 100 times higher than those in conventional radiofrequency or even superconducting radiofrequency cavities. This opens a transformative path towards novel, compact and potentially ubiquitous accelerators. These prospects, and the increasing demand for electron accelerator beamtime for various applications in natural, material and life sciences, motivate the research and development on novel plasma-based accelerator concepts. However, these electron beam sources need to be understood and controlled. The focus of this thesis is on electron beam-driven plasma wakefield acceleration (PWFA) and the controlled injection and acceleration of secondary electron bunches in the accelerating wake fields by means of a short-pulse near-infrared laser. Two laser-triggered injection methods are explored. The first one is the Trojan Horse Injection, which relies on very good alignment and timing control between electron beam and laser pulse and then promises electron bunches with hitherto unprecedented quality as regards emittance and brightness. The physics of electron injection in the Trojan Horse case is explored with a focus on the final longitudinal bunch length. Then a theoretical and numerical study is presented that examines the physics of Trojan Horse injection when performed in an expanding wake generated by a smooth density down-ramp. The benefits are radically decreased drive-electron bunch requirements and a unique bunch-length control that enables longitudinal electron-bunch shaping. The second laser-triggered injection method is the Plasma Torch Injection, which is a versatile, all-optical laser-plasma-based method capable to realize tunable density downramp injection. At the SLAC National Laboratory, the first proof-of-principle was achieved both for Trojan Horse and Plasma Torch injection. Setup details and results are reported in the experimental part of the thesis along with the commissioning

Electron cyclotron harmonic wave acceleration

Science.gov (United States)

Karimabadi, H.; Menyuk, C. R.; Sprangle, P.; Vlahos, L.

1987-01-01

A nonlinear analysis of particle acceleration in a finite bandwidth, obliquely propagating electromagnetic cyclotron wave is presented. It has been suggested by Sprangle and Vlahos in 1983 that the narrow bandwidth cyclotron radiation emitted by the unstable electron distribution inside a flaring solar loop can accelerate electrons outside the loop by the interaction of a monochromatic wave propagating along the ambient magnetic field with the ambient electrons. It is shown here that electrons gyrating and streaming along a uniform, static magnetic field can be accelerated by interacting with the fundamental or second harmonic of a monochromatic, obliquely propagating cyclotron wave. It is also shown that the acceleration is virtually unchanged when a wave with finite bandwidth is considered. This acceleration mechanism can explain the observed high-energy electrons in type III bursts.

Electron cyclotron harmonic wave acceleration

International Nuclear Information System (INIS)

Karimabadi, H.; Menyuk, C.R.; Sprangle, P.; Vlahos, L.; Salonika Univ., Greece)

1987-01-01

A nonlinear analysis of particle acceleration in a finite bandwidth, obliquely propagating electromagnetic cyclotron wave is presented. It has been suggested by Sprangle and Vlahos in 1983 that the narrow bandwidth cyclotron radiation emitted by the unstable electron distribution inside a flaring solar loop can accelerate electrons outside the loop by the interaction of a monochromatic wave propagating along the ambient magnetic field with the ambient electrons. It is shown here that electrons gyrating and streaming along a uniform, static magnetic field can be accelerated by interacting with the fundamental or second harmonic of a monochromatic, obliquely propagating cyclotron wave. It is also shown that the acceleration is virtually unchanged when a wave with finite bandwidth is considered. This acceleration mechanism can explain the observed high-energy electrons in type III bursts. 31 references

Post-irradiation degradation of DNA in electron and neutron-irradiated E. coli B/r; the effect of the radiation sensitizer metronidazole

Energy Technology Data Exchange (ETDEWEB)

Cramp, W A; George, A M; Howlett, J [Hammersmith Hospital, London (UK). M.R.C. Cyclotron Unit

1976-04-01

Suspensions of E.coli B/r were irradiated under aerobic and anoxic conditions with electrons (7 to 8 MeV, 2 and 20 krad/min, MRC linear accelerator), or with neutrons (average energy 7.5 MeV, 2 krad/min, MRC cyclotron) in an investigation of the effects of the radiosensitizer, metronidazole (Flagyl, 5 or 10 mM) on survival and DNA degradation. These results are compared with those for another electron affinic radiosensitizer, indane trione. Survival studies yielded enhancement ratios, for anoxic irradiation only, of 1.7 (5mM) and 1.9 (10mM) for electrons, and 1.2 (5mM and 10mM) for neutrons. Unlike indane trione, metronidazole had no pronounced inhibitory effect on post-irradiation DNA degradation, either when incubated with the bacteria before irradiation or when present during irradiation. When present under anoxic conditions of irradiation with electrons, some enhancement of degradation was observed. DNA degradation was reduced at higher doses, with a pronounced maxiumum effect, for neutrons as well as for electrons. Metronidazole allowed this degradation to continue and showed some sensitizing action, but did not prevent the decrease in total degradation at high doses. It is therefore difficult to correlate DNA degradation with cell-depth.

Dynamic investigation of electron trapping and charge decay in electron-irradiated Al sub 2 O sub 3 in a scanning electron microscope: Methodology and mechanisms

CERN Document Server

Fakhfakh, S; Belhaj, M; Fakhfakh, Z; Kallel, A; Rau, E I

2002-01-01

The charging and discharging of polycrystalline Al sub 2 O sub 3 submitted to electron-irradiation in a scanning electron microscope (SEM) are investigated by means of the displacement current method. To circumvent experimental shortcomings inherent to the use of the basic sample holder, a redesign of the latter is proposed and tests are carried out to verify its operation. The effects of the primary beam accelerating voltage on charging, flashover and discharging phenomena during and after electron-irradiation are studied. The experimental results are then analyzed. In particular, the divergence between the experimental data and those predicted by the total electron emission yield approach (TEEYA) is discussed. A partial discharge was observed immediately after the end of the electron-irradiation exposure. The experimental data suggests, that the discharge is due to the evacuation to the ground, along the insulator surface, of released electrons from shallow traps at (or in the close vicinity of) the insulat...

Possibility in application of electron beam irradiation to plant quarantine of cut flowers

International Nuclear Information System (INIS)

Tanabe, Kazuo

1994-01-01

For the purpose of developing new quarantine procedure alternative to fumigation, electron beam irradiation was examined in the disinfestation of arthroped pests that infest cut flowers. Immature and adult two-spotted spider mites, Tetranychus urticae, which is a typical pest in horticulture due to high fertility, parthenogenesis and chemical resistance, were irradiated at a Van de graaf electron accelerator (2.5 MeV) at 0.2 - 1.4 kGy. They decreased radiosensitivity with aging. Female was much more tolerant than male throughout their life. Irradiation controlled the fertility of both sexes, and also feeding and behavioral activities. Cut flowers irradiated with the Dynamitron accelerator (5 MeV) showed various responses according to species, cultivars and tissues of plants. Carnations, tulips and gladioluses were tolerant in disinfesting or sterilizing, but some cultivars of chrysanthemum and rose showed the symptom of injury, in which flowering was delayed at low dose, and the failure of flowering and the chlorosis of leaves occurred at high dose. Floral organs were much more sensitive to radiation than others. Sensitive plants also showed the reduced production of ethylene. (K.I.)

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

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Maiara S.; Sartori, Mariana N.; Oliveira, Rene R.; Moura, Esperidiana A.B., E-mail: maiara.sferreira@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

In recent years, research on the replacement of synthetic fibers by natural fibers as reinforcement in thermoplastic composites has increased dramatically due to the advantages of natural fibers, such as low density, low cost, environmental appeal and recyclability. In the present work, the influence of electron-beam irradiation on mechanical properties of HDPE and HDPE/Brazil Nut Shell (Bertholletia excelsa) fiber compositive was investigated. The HDPE composite reinforced with 5% or 10%, by weight of Brazil nut shell fiber powder with particle sizes equal or smaller than 250 μm were obtained by extrusion, using a twin screw extruder. The materials were irradiated at 200 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated specimens tests samples were submitted to mechanical and thermo-mechanical tests, scanning electron microscopy (SEM), X-Ray diffraction (XRD) and sol-gel analysis and the correlation between their properties was discussed. The results showed significant changes in HDPE mechanical and thermo-mechanical properties due to Brazil nut shell fibers addition and electron-beam irradiation. The surface of the cryo fractured composite samples irradiated showed important visual changes which suggest a better fiber-matrix interfacial adhesion, due to irradiation treatment. These results showed that it is possible to get interesting property gains by using waste from renewable sources instead of the traditional ones and electron-beam radiation treatment. (author)

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

International Nuclear Information System (INIS)

Ferreira, Maiara S.; Sartori, Mariana N.; Oliveira, Rene R.; Moura, Esperidiana A.B.

2013-01-01

In recent years, research on the replacement of synthetic fibers by natural fibers as reinforcement in thermoplastic composites has increased dramatically due to the advantages of natural fibers, such as low density, low cost, environmental appeal and recyclability. In the present work, the influence of electron-beam irradiation on mechanical properties of HDPE and HDPE/Brazil Nut Shell (Bertholletia excelsa) fiber compositive was investigated. The HDPE composite reinforced with 5% or 10%, by weight of Brazil nut shell fiber powder with particle sizes equal or smaller than 250 μm were obtained by extrusion, using a twin screw extruder. The materials were irradiated at 200 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated specimens tests samples were submitted to mechanical and thermo-mechanical tests, scanning electron microscopy (SEM), X-Ray diffraction (XRD) and sol-gel analysis and the correlation between their properties was discussed. The results showed significant changes in HDPE mechanical and thermo-mechanical properties due to Brazil nut shell fibers addition and electron-beam irradiation. The surface of the cryo fractured composite samples irradiated showed important visual changes which suggest a better fiber-matrix interfacial adhesion, due to irradiation treatment. These results showed that it is possible to get interesting property gains by using waste from renewable sources instead of the traditional ones and electron-beam radiation treatment. (author)

Resent advance in electron linear accelerators

International Nuclear Information System (INIS)

Takeda, Seishi; Tsumori, Kunihiko; Takamuku, Setsuo; Okada, Toichi; Hayashi, Koichiro; Kawanishi, Masaharu

1986-01-01

In recently constructed electron linear accelerators, there has been remarkable advance both in acceleration of a high-current single bunch electron beam for radiation research and in generation of high accelerating gradient for high energy accelerators. The ISIR single bunch electron linear accelerator has been modified an injector to increase a high-current single bunch charge up to 67 nC, which is ten times greater than the single bunch charge expected in early stage of construction. The linear collider projects require a high accelerating gradient of the order of 100 MeV/m in the linear accelerators. High-current and high-gradient linear accelerators make it possible to obtain high-energy electron beam with small-scale linear accelerators. The advance in linear accelerators stimulates the applications of linear accelerators not only to fundamental research of science but also to industrial uses. (author)

Evaluation of induced radioactivity in 10 MeV-electron irradiated spices, (1)

International Nuclear Information System (INIS)

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

1994-01-01

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

Dosimetry for electron beam from Microtron accelerator using chemical dosimeters

International Nuclear Information System (INIS)

Joseph, Praveen; Nairy, Rajesha; Sanjeev, Ganesh; Narayana, Y.

2014-01-01

The Microtron is a simple, compact, low cost electron accelerator with excellent beam quality and it can accelerate electrons to relativistic energies. The variable energy Microtron at Mangalore University is used for R and D programmes in basic and applied areas of physics, chemistry, materials science, biological sciences, medical science and industry. While studying the effects of radiation, it is essential to have complete knowledge of absorbed dose. In the present study the absorbed dose and the uniformity of dose distribution at various points due to 8 MeV electron beam from Microtron accelerator has been calculated using different chemical dosimeters. From the dosimetry studies for Microtron accelerator, it is observed that the absorbed doses measured at various dose ranges from 2 Gy to 25 kGy using FBX dosimeters at very low doses, Fricke at intermediate doses and alanine and glutamine at higher doses, varied linearly with increasing electron counts. From the dosimetry studies it is observed that there is a linear relation between dose and electron numbers over a wide range of absorbed doses. It is evaluated that the electron counts of about 1.15 x 10 14 corresponds to an absorbed dose of 100 Gy. Fricke dosimetry was carried out to measure the uniformity in dose distribution at a distance of 30 cm from the beam exit window of the accelerator to ensure the availability of uniform irradiation field size. It is observed that a field size of about 4 x 4 cm is available at 30 cm distance from the beam exit window over which the dose distribution is uniform. The sample size during radiological studies using Microtron was restricted to less than 4 x 4 cm dimension at 30 cm distance from the beam exit window to ensure uniform dose distribution to the sample

Evaluation of induced radioactivity in 10 MeV electron-irradiated spices

Energy Technology Data Exchange (ETDEWEB)

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

1993-10-01

In order to make clear appreciation to induced radioactivity in the irradiated foods, photonuclear reactions which could produce radioactivity at energies up to 10 MeV were listed up from elemental compositions of black pepper, white pepper, red pepper, ginger and turmeric. The samples were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy and radioactivity was measured. Induced radioactivity could not be detected significantly by gamma-ray spectrometry and beta-ray counting in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list. 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. (J.P.N.).

Electron accelerators and applications in Korea

International Nuclear Information System (INIS)

Han, Bumsoo

2006-01-01

Types of high-energy radiation were discovered more than one hundred years ago. Since then, properties of radiation providing ability to modify physico-chemical properties of materials have found many applications. Radiation technologies applying gamma sources as well as electron accelerators for treatment of materials are well-established processes. Worldwide, there are over 2000 industrial gamma irradiators and 1,300 industrial electron accelerators in operation that are being widely used for sterilization, food irradiation and polymer processing. Indeed, radiation processing is today a well established multi-billion dollar industry world over that is providing unique high value products for mankind in an environmentally friendly manner. Electron accelerators are introduced at late 70s in Korea, firstly for researches and later for insulated wire and cable production, and up to now, over 30 accelerators are used in industries. They are mainly for cable productions, thermo-shrinkable materials, foam sheets, coating and curing and others. While polymerization and polymer modification have proved to be the most widespread applications of radiation processing, many other applications, such as environmental protection is becoming an increasingly important concern in industrialized nations, and wide ranging investigations have identified several areas of waste control to which radiation processing may contribute. In recent years, large metropolitan cities including Seoul, Tokyo and other major cities have been facing the challenge of increasing environmental pollution resulting from ever increasing population and industrial activities. As a result, issues regarding environmental pollution, be it air, liquid or solid, are becoming significant matters of concern. The realization that such pollutants pose a serious threat to human health has necessitated the need for development of cost effective and environmentally friendly technologies to overcome the problem. Radiation

Magnetic, thermal and luminescence properties in room-temperature nanosecond electron-irradiated various metal oxide nanopowders

Science.gov (United States)

Sokovnin, S. Yu; Balezin, M. E.; Il’ves, V. G.

2018-03-01

By means of pulsed electron beam evaporation in vacuum of targets non-magnetic, in bulk state, Al2O3 and YSZ (ZrO2-8% Y2O3) oxides, magnetic nanopowders (NPs) with a high specific surface were produced. The NPs were subsequently irradiated in air by electrons with energy of 700 keV, using a URT-1 accelerator for 15 and 30 minutes. The magnetic, thermal, and pulsed cathodoluminescence (PCL) characteristics of NPs were measured before and after irradiation. It was established that the electron irradiation non-monotonically changes the magnetization of the pristine samples. To the contrary, a clear correlation between the intensity of PCL and the irradiation doses is found in the oxides. There was a decrease in the intensity of PCL after irradiation. Luminescent and thermal properties reflect the transformation of structural defects in NPs more strongly after the exposure to a pulsed electron beam in comparison with corresponding changes of the NPs magnetic response.

Fabrication of Nonvolatile Memory Effects in High-k Dielectric Thin Films Using Electron Irradiation

International Nuclear Information System (INIS)

Park, Chanrock; Cho, Daehee; Kim, Jeongeun; Hwang, Jinha

2010-01-01

Electron Irradiation can be applied towards nano-floating gate memories which are recognized as one of the next-generation nonvolatile memory semiconductors. NFGMs can overcome the preexisting limitations encountered in Dynamic Random Access Memories and Flash memories with the excellent advantages, i. e. high-density information storage, high response speed, high compactness, etc. The traditional nano-floating gate memories are fabricated through multi-layered nano structures of the dissimilar materials where the charge-trapping portions are sandwiched into the high-k dielectrics. However, this work reports the unique nonvolatile responses in single-layered high-k dielectric thin films if irradiated with highly accelerated electron beams. The implications of the electron irradiation will be discussed towards high-performance nano-floating gate memories

Generation of intense spin-polarized electron beams at the electron accelerator facility ELSA

International Nuclear Information System (INIS)

Heiliger, Dominik

2014-08-01

The inverted source of polarized electrons at the electron accelerator ELSA in Bonn routinely provides a pulsed and low energetic beam of polarized electrons (100 mA, 48 keV) by irradiating a GaAs strained-layer superlattice photocathode with laser light. Due to the beam energy of 48 keV the beam transport to the linear accelerator is strongly space charge dominated and the actual beam current has an impact on the beam dynamics. Thus, the optics of the transfer line to the linear accelerator must be optimized with respect to the chosen beam intensity. An intensity upgrade including numerical simulations of the beam transport as well as a generation and a transport of a beam current of nearly 200 mA was successfully operated. In order to enhance the reliability and uptime of the source, a new extreme high vacuum load lock system was installed and commissioned. It consists of an activation chamber for heat cleaning of the photocathodes and activation with cesium and oxygen, a storage in which different types of photocathodes can be stored and a loading chamber in which an atomic hydrogen source is used to remove nearly any remaining surface oxidation. The new cleaning procedure with atomic hydrogen was investigated regarding its potential to restore the initial quantum efficiency of the photocathode after many activations.

Electron accelerators: History, applications, and perspectives

International Nuclear Information System (INIS)

Martins, M.N.; Silva, T.F.

2014-01-01

This paper will present an outlook on sources of radiation, focusing on electron accelerators. We will review advances that were important for the development of particle accelerators, concentrating on those that led to modern electron accelerators. Electron accelerators are multipurpose machines that deliver beams with energies spanning five orders of magnitude, and are used in applications that range from fundamental studies of particle interactions to cross-linking polymer chains in industrial plants. Each accelerator type presents specific characteristics that make it more suitable for certain applications. Our work will focus on radiation sources for medical applications, dominated by electron linacs (linear accelerators), and those used for research, field where electron rings dominate. We will outline the main technological advances that occurred in the past decades, which made possible the construction of machines fit for clinical environments. Their compactness, efficiency and reliability have been key to their acceptance in clinical applications. This outline will include advances that allowed for the construction of brighter synchrotron light sources, where the relevant beam characteristics are good optical quality and high beam current. The development of insertion devices will also be discussed, as well the development of Free Electron Lasers (FEL). We conclude the review with an outline of the new developments of electron accelerators and the expectations for Energy Recovery Linacs. - Highlights: ► We present an outlook on sources of radiation, focusing on electron accelerators. ► We review important advances for the development of modern electron accelerators. ► We outline advances that allowed for brighter synchrotron light sources. ► We describe the history of the development of electron accelerators in Brazil

Size Control Technology of Silver Nanoparticles Using Electron Beam Irradiation

International Nuclear Information System (INIS)

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

2013-01-01

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

Size Control Technology of Silver Nanoparticles Using Electron Beam Irradiation

Energy Technology Data Exchange (ETDEWEB)

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

2013-12-15

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

Basic Design Study on 1-MV Electrostatic Accelerator for ion irradiation

International Nuclear Information System (INIS)

Cho, Yongsub; Kim, Kyeryung; Lee, Chanyoung

2014-01-01

The KOMAC (KOrea Multi-purpose Accelerator Complex) has electrostatic ion accelerators whose terminal voltages are less than 100kV. To extend ion beam irradiations with higher energy ions for industrial purposes, an electrostatic accelerator of 1-MV terminal voltage should have been studied. For industrial applications, the most important features of the accelerator are high current and high reliability for high irradiation dose and high through-put with high current and long irradiation time. The basic study on 1-MV electrostatic ion accelerator for industrial applications has been done. The key components are a high voltage power supply, an ion source, and an accelerating column. The feasibility study for fabrication is being performed. Especially the R and D for ion source is required. The 1-MV ion accelerator will be constructed with domestic companies and installed in the beam application research building, which is under construction in the site of KOMAC at Gyeongju

Current status of electron beam processing applications and accelerator technology in India

International Nuclear Information System (INIS)

Sarma, K.S.S.; Lavale, D.S.; Sabharwal, S.

2001-01-01

Full text: Electron Beam (EB) processing is now a well established technology world over in a few specific sections of the industry, particularly the polymer industry. The actual use of the technology however is dependent upon the specific socioeconomic needs of the individual country. In India, an industrial type EB accelerator has been operative since 1988 at Bhabha Atomic Research Centre, Mumbai. This 2 MeV, 20 kW machine is being utilized to develop and optimize process and material process techniques for research, development and industry in the fields viz., crosslinking, degradation and grafting of polymers; color enhancement in precious and semi-precious stones, lifetime control in semi-conductor devices; food irradiation. Some of these processes have developed into products that are now being carried out on regular commercial basis, meeting the requirements of the Indian industry. These include crosslinked high temperature PE 'O' rings, wire and cable insulation, heat shrinkable tubes; micro-fine PTFE powder, degraded viscose rayon pulp and color diamonds, With the collaboration of Indian cable industry, EB crosslinkable insulation formulations were developed. Suitable irradiation parameters and techniques have been studied, optimized and standardized. Over 100 km length of cables based on PE, PVC and elastomer blends has been irradiated and the results were found to be very encouraging. Since the main parameters to be monitored in the radiation processing is the absorbed dose and its uniformity in the product, dose evaluation and optimization hb been carried out specific to the process and the product under treatment. EB dosimetry based on the graphite calorimetry, thin film and alanine powder dosimeters has been standardized and being used in the facility for dose evaluation and optimization studies. An endless stainless steel mesh conveyor is available in the facility to carry out product irradiation. An eight type cable irradiation gadget has been

Industrial irradiation

International Nuclear Information System (INIS)

Stirling, Andrew

1995-01-01

Production lines for rubber gloves would not appear to have much in common with particle physics laboratories, but they both use accelerators. Electron beam irradiation is often used in industry to improve the quality of manufactured goods or to reduce production cost. Products range from computer disks, shrink packaging, tyres, cables, and plastics to hot water pipes. Some products, such as medical goods, cosmetics and certain foodstuffs, are sterilized in this way. In electron beam irradiation, electrons penetrate materials creating showers of low energy electrons. After many collisions these electrons have the correct energy to create chemically active sites. They may either break molecular bonds or activate a site which promotes a new chemical linkage. This industrial irradiation can be exploited in three ways: breaking down a biological molecule usually renders it useless and kills the organism; breaking an organic molecule can change its toxicity or function; and crosslinking a polymer can strengthen it. In addition to traditional gamma irradiation using isotopes, industrial irradiation uses three accelerator configurations, each type defining an energy range, and consequently the electron penetration depth. For energies up to 750 kV, the accelerator consists of a DC potential applied to a simple wire anode and the electrons extracted through a slot in a coaxially mounted cylindrical cathode. In the 1-5 MeV range, the Cockcroft-Walton or Dynamitron( R ) accelerators are normally used. To achieve the high potentials in these DC accelerators, insulating SF6 gas and large dimension vessels separate the anode and cathode; proprietary techniques distinguish the various commercial models available. Above 5 MeV, the size of DC accelerators render them impractical, and more compact radiofrequency-driven linear accelerators are used. Irradiation electron beams are actually 'sprayed' over the product using a magnetic deflection system. Lower energy beams of

Contribution of Brazil nut shell fiber and electron-beam irradiation in thermomechanical properties of HDPE

International Nuclear Information System (INIS)

Polato, Pamella; Lorusso, Leandro Alex; Souza, Clecia de Moura; Moura, Esperidiana Augusta Barretos de; Chinellato, Anne; Rosa, Ricardo de

2010-01-01

In the present work, the influence of electron-beam irradiation on thermo-mechanical properties of HDPE and HDPE/Brazil nut shell fiber composite was investigated. The materials were irradiated at radiation dose 50 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated samples were submitted to thermo-mechanical tests and the correlation between their properties was discussed. The results showed that the incorporation of Brazil nut shell fiber represented a significant gain (p < 0,05) in tensile strength at break, flexural strength, flexural module, Vicat softening temperature and heat distortion temperature (HDT) properties of the HDPE. In addition, the irradiated HDPE/Brazil nut shell fiber composite presented a significant increase (p < 0.05) in this properties compared with irradiated HDPE. (author)

Experimental destruction of Ascarid ova in sewage sludge by accelerated electron irradiation

International Nuclear Information System (INIS)

Horak, Petr

1994-01-01

Aerobically-treated sewage sludge containing eggs of the nematode Ascaris suum was processed using accelerated electrons. After 8 weeks of incubation the morphological and developmental status of eggs was determined. Inhibition of development and the destruction of nematode embryos within eggs were observed at doses over 1.1 kGy. (author)

12 MeV, 4.3 kW electron linear accelerator irradiation application

International Nuclear Information System (INIS)

Hang Desheng; Lai Qiji

2000-01-01

Characteristics of an electron linear accelerator, which has 6-12 MeV energy, 4.2 kW average beam power is introduced. Results show that it has advantages on improving the characteristics of semiconductor devices such as diodes, triodes, SCR, preventing garlic from sprout, preservation of food, and so on

Utilization of electron accelerator in the Philippines

Energy Technology Data Exchange (ETDEWEB)

Cabalfin, Estelita G. [Philippine Nuclear Research Institute, Quezon (Philippines)

2003-02-01

Radiosterilization of medical and surgical supplies, radiation treatment of consumer products such as food, pharmaceuticals and cosmetics, and the modification of polymers, crosslinking or curing, using gamma irradiation facilities in Philippine industries are overviewed. Philippine Nuclear Research Institute(PNRI) conducts bioburden determination, dose setting and validation of compatibility with radiation of product and packaging with the technical assistance of IAEA. The products with yields treated at the irradiation facility from 1996-2001 are shown in table. An electron accelerator of 10 MeV and 28 kW, established by Terumo Corporation, is used since 2000 for in-house radiation sterilization of syringes. Current regulations and regulatory authority in Philippines are also briefly introduced. Future processes such as radiation vulcanized natural rubber latex (RVNRL), use of carrageenan as hydrogel for dressing wounds and others and fermented bagasse as animal feed are now in progress. (S. Ohno)

Utilization of electron accelerator in the Philippines

International Nuclear Information System (INIS)

Cabalfin, Estelita G.

2003-01-01

Radiosterilization of medical and surgical supplies, radiation treatment of consumer products such as food, pharmaceuticals and cosmetics, and the modification of polymers, crosslinking or curing, using gamma irradiation facilities in Philippine industries are overviewed. Philippine Nuclear Research Institute(PNRI) conducts bioburden determination, dose setting and validation of compatibility with radiation of product and packaging with the technical assistance of IAEA. The products with yields treated at the irradiation facility from 1996-2001 are shown in table. An electron accelerator of 10 MeV and 28 kW, established by Terumo Corporation, is used since 2000 for in-house radiation sterilization of syringes. Current regulations and regulatory authority in Philippines are also briefly introduced. Future processes such as radiation vulcanized natural rubber latex (RVNRL), use of carrageenan as hydrogel for dressing wounds and others and fermented bagasse as animal feed are now in progress. (S. Ohno)

Management of the installation of a 10 MeV, 50 kW electron-beam irradiator

International Nuclear Information System (INIS)

Lawrence, C.B.; Armstrong, L.; Drewell, N.H.; McKeown, J.; Scott, L.; O'Brien, D.; Svendsen, E.

1995-08-01

An IMPELA-10/50 electron-beam irradiator has been installed by AECL Accelerators in Iotron Industries' service centre near Vancouver. Construction of the facility, installation of the accelerator and conveyor, and commissioning to the full rated power of 50 kW were completed in 12 months. Iotron began commercial irradiation immediately and the first continuous operation achieved 250 hours of production in 12 days. The engineering, production and project management organizations and activities to complete the on-schedule installation and commissioning are reviewed. (author). 3 refs., 2 tabs., 1 fig

Development of an irradiation device for electron beam wastewater treatment

International Nuclear Information System (INIS)

Rela, Paulo Roberto

2003-01-01

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

Oxidative decomposition of aromatic hydrocarbons by electron beam irradiation

Science.gov (United States)

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

2003-05-01

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

Auroral electron acceleration

International Nuclear Information System (INIS)

Bryant, D.A.

1989-10-01

Two theories of auroral electron acceleration are discussed. Part 1 examines the currently widely held view that the acceleration is an ordered process in a quasi-static electric field. It is suggested that, although there are many factors seeming to support this theory, the major qualifications and uncertainties that have been identified combine to cast serious doubt over its validity. Part 2 is devoted to a relatively new interpretation in terms of stochastic acceleration in turbulent electric fields. This second theory, which appears to account readily for most known features of the electron distribution function, is considered to provide a more promising approach to this central question in magnetospheric plasma physics. (author)

Modulation of accelerated repopulation in mouse skin during daily irradiation

International Nuclear Information System (INIS)

Trott, K.-R.; Shirazi, A.; Heasman, F.

1999-01-01

Background and purpose: The timing of acceleration of repopulation in the epidermis during daily irradiation is related to the development of skin erythema and epidermal hypoplasia. Therefore, the relationship between impairment of the epidermal barrier function, the dermal inflammatory response and epidermal hypoplasia with the acceleration of repopulation was investigated.Materials and purpose: Skin fields of approximately 1 cm 2 on the thighs of TUC mice were given five daily fractions of 3 Gy in each week followed by top-up doses at the end of the first, the second, or the third week to determine residual epidermal tolerance and to calculate repopulation rates in weeks 1, 2, or 3. Systemic modulation of repopulation was attempted by daily indomethacine during fractionated irradiation whereas tape stripping or UV-B exposure before the start of fractionated irradiation attempted local modulation. In parallel experiments, the water permeability coefficient of the epidermis was determined ex vivo by studying transepidermal transport of tritiated water.Results: Without modulation, no repopulation was found in the first week of daily fractionation but repopulation compensated 30% of the dose given in week two and 70% of the dose given in week three. Only tape stripping before the start of fractionated irradiation accelerated repopulation in week one. UV-B had no effect on repopulation although it stimulated proliferation as much as tape stripping. Indomethacin did not suppress acceleration of repopulation. A significant increase in transepidermal water loss was found but only after repopulation had already accelerated.Conclusions: Acceleration of repopulation in mouse epidermis during daily-fractionated irradiation is not related to the simultaneous development of an inflammatory response. Also, the loss of the epidermal barrier function is not involved in the development of the acceleration response, which rather seems to be triggered directly by the decreased

Irradiation of aluminium alloy materials with electron beam

International Nuclear Information System (INIS)

Konno, Osamu; Masumoto, Kazuyoshi

1982-01-01

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

In vivo dosimetry with MOSFETs and GAFCHROMIC films during electron IORT for Accelerated Partial Breast Irradiation.

Science.gov (United States)

Petoukhova, Anna; Rüssel, Iris; Nijst-Brouwers, Julienne; van Wingerden, Ko; van Egmond, Jaap; Jacobs, Daphne; Marinelli, Andreas; van der Sijp, Joost; Koper, Peter; Struikmans, Henk

2017-12-01

The purpose of this study was to compare the delivered dose to the expected intraoperative radiation therapy (IORT) dose with in vivo dosimetry. For IORT using electrons in accelerated partial breast irradiation, this is especially relevant since a high dose is delivered in a single fraction. For 47 of breast cancer patients, in vivo dosimetry was performed with MOSFETs and/or GAFCHROMIC EBT2 films. A total dose of 23.33 Gy at d max was given directly after completing the lumpectomy procedure with electron beams generated with an IORT dedicated mobile accelerator. A protection disk was used to shield the thoracic wall. The results of in vivo MOSFET dosimetry for 27 patients and GAFROMIC film dosimetry for 20 patients were analysed. The entry dose for the breast tissue, measured with MOSFETs, (mean value 22.3 Gy, SD 3.4%) agreed within 1.7% with the expected dose (mean value 21.9 Gy). The dose in breast tissue, measured with GAFCHROMIC films (mean value 23.50 Gy) was on average within 0.7% (SD = 3.7%, range -5.5% to 5.6%) of the prescribed dose of 23.33 Gy. The dose measured with MOSFETs and GAFROMIC EBT2 films agreed well with the expected dose. For both methods, the dose to the thoracic wall, lungs and heart for left sided patents was lower than 2.5 Gy even when 12 MeV was applied. The positioning time of GAFCHROMIC films is negligible and based on our results we recommend its use as a standard tool for patient quality assurance during breast cancer IORT. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

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

CERN Document Server

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

2002-01-01

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

Effect of ammonia and electron beam irradiation on lignocelulosic materials

International Nuclear Information System (INIS)

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

1986-01-01

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

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

International Nuclear Information System (INIS)

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

2016-01-01

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

Thermoluminescent characteristics of CaSO{sub 4}:Dy+PTFE irradiated with high energy electron beams; Caracteristicas termoluminiscentes del CaSO{sub 4}:Dy+PTFE irradiado con haces de electrones de alta energia

Energy Technology Data Exchange (ETDEWEB)

Alvarez, R.; Rivera, T.; Calderon, J. A.; Jimenez, Y. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Rodriguez, J. [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Mexico D. F. (Mexico); Oviedo, O. [Centro Medico ABC, Sur 136 No. 116, Col. Las Americas, 01120 Mexico D. F. (Mexico); Azorin, J., E-mail: chagua@hotmail.com [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, 09340 Mexico D. F. (Mexico)

2011-10-15

In the present work thermoluminescent response of dysprosium doped calcium sulfate embedded in polytetrafluorethylene (CaSO{sub 4}:Dy+PTFE) under high electron beam irradiations from linear accelerator for clinical applications was investigated. The irradiations were carried out using high electron beams (6 to 18 MeV) from a linear accelerator Varian, C linac 2300C/D, for clinical practice purpose. The electron irradiations were obtained by using the water solid in order to guarantee electronic equilibrium conditions. Field shaping for electron beams was obtained with electron cones. Glow curve and other thermoluminescent characteristics of CaSO{sub 4}:Dy+PTFE were conducted under high electron beams irradiations. The thermoluminescent response of the pellets showed and intensity peak centered at around 235 C. Thermoluminescent response of CaSO{sub 4}:Dy+PTFE as a function of high electron absorbed dose showed a linearity in a wide range. To obtain reproducibility characteristic, a set of pellets were exposed repeatedly for the same electron absorbed dose. The results obtained in this study can suggest the applicability of CaSO{sub 4}:Dy+PTFE pellets for high electron beam dosimetry, provided fading is correctly accounted for. (Author)

Radiation processing of liquid with low energy electron accelerator

International Nuclear Information System (INIS)

Makuuchi, Keizo

2003-01-01

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

Radiation processing of liquid with low energy electron accelerator

Energy Technology Data Exchange (ETDEWEB)

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

2003-02-01

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

Electron dosimetry in irradiation processing with rad-hard diodes

International Nuclear Information System (INIS)

Santos, Thais Cavalheri dos

2012-01-01

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

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

International Nuclear Information System (INIS)

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

2011-01-01

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

Electron accelerators for waste processing

International Nuclear Information System (INIS)

Kon'kov, N.G.

1976-01-01

The documents of the International symposium on radiation vaste processing are presented. Questions on waste utilization with the help of electron accelerators are considered. The electron accelerators are shown to have an advantage over some other ionizing radiation sources. A conclusion is made that radiation methods of waste processing are extensively elaborated in many developed countries. It has been pointed out that an electron accelerator is a most cheap and safe ionizing radiation source primarily for processing of gaseous and liquid wastes

Control of electron injection and acceleration in laser-wakefield accelerators

International Nuclear Information System (INIS)

Guillaume, E.

2015-01-01

Laser-plasma accelerators provide a promising compact alternative to conventional accelerators. Plasma waves with extremely strong electric fields are generated when a high intensity laser is focused into an underdense gas target. Electrons that are trapped in these laser-driven plasma waves can be accelerated up to energies of a few GeVs. Despite their great potential, laser-wakefield accelerators face some issues, regarding notably the stability and reproducibility of the beam when electrons are injected in the accelerating structure. In this manuscript, different techniques of electron injection are presented and compared, notably injection in a sharp density gradient and ionization injection. It is shown that combining these two methods allows for the generation of stable and tunable electron beams. We have also studied a way to manipulate the electron bunch in the phase-space in order to accelerate the bunch beyond the dephasing limit. Such a technique was used with quasi-monoenergetic electron beams to enhance their energy. Moreover, the origin of the evolution of the angular momentum of electrons observed experimentally was investigated. Finally, we demonstrated experimentally a new method - the laser-plasma lens - to strongly reduce the divergence of the electron beam. This laser-plasma lens consists of a second gas jet placed at the exit of the accelerator. The laser pulse drives a wakefield in this second jet whose focusing forces take advantage to reduce the divergence of the trailing electron bunch. A simple analytical model describing the principle is presented, underlining the major importance of the second jet length, density and distance from the first jet. Experimental demonstration of the laser-plasma lens shows a divergence reduction by a factor of 2.6 for electrons up to 300 MeV, in accordance with the model predictions

Gamma and electron beam irradiation effects on SiR-EPDM blends

Directory of Open Access Journals (Sweden)

R. Deepalaxmi

2014-07-01

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

Acceleration of polarized electrons in the Bonn electron-accelerator facility ELSA

International Nuclear Information System (INIS)

Hoffmann, M.

2001-12-01

The future medium energy physics program at the electron stretcher accelerator ELSA of Bonn University mainly relies on experiments using polarized electrons in the energy range from 1 to 3.2 GeV. To prevent depolarization during acceleration in the circular accelerators several depolarizing resonances have to be corrected for. Intrinsic resonances are compensated using two pulsed betatron tune jump quadrupoles. The influence of imperfection resonances is successfully reduced applying a dynamic closed orbit correction in combination with an empirical harmonic correction on the energy ramp. Both types of resonances and the correction techniques have been studied in detail. The imperfection resonances were used to calibrate the energy of the stretcher ring with high accuracy. A new technique to extract the beam with horizontal oriented polarization was successfully installed. For all energies a polarized electron beam with more than 50% polarization can now be supplied to the experiments at ELSA, which is demonstrated by measurements using a Moeller polarimeter installed in the external beamline. (orig.)

Effects of high-energy electron irradiation of chicken meat on Salmonella and aerobic plate count

International Nuclear Information System (INIS)

Heath, J.L.; Owens, S.L.; Tesch, S.; Hannah, K.W.

1990-01-01

Four experiments were used to determine the effects of high-energy irradiation on the number of aerobic microorganisms and Salmonella on broiler breasts and thighs. Irradiation ranging from 100 to 700 kilorads (krads) was provided by a commercial-scale, electron-beam accelerator. Irradiation of broiler breast and thigh pieces with electron beams at levels of 100, 200, 300, 400, 500, and 600 krads showed that levels as low as 100 krads would eliminate Salmonella. When 33 thighs were tested after irradiation at 200 krads, only one thigh tested presumptive positive. The total number of aerobic organisms was reduced by 2 to 3 log10 cycles at irradiation levels of 100, 200, 300, 400, 500, 600, and 700 krads. Increasing the dose above 100 krads gave little if any additional benefit

Electron acceleration by turbulent plasmoid reconnection

Science.gov (United States)

Zhou, X.; Büchner, J.; Widmer, F.; Muñoz, P. A.

2018-04-01

In space and astrophysical plasmas, like in planetary magnetospheres, as that of Mercury, energetic electrons are often found near current sheets, which hint at electron acceleration by magnetic reconnection. Unfortunately, electron acceleration by reconnection is not well understood yet, in particular, acceleration by turbulent plasmoid reconnection. We have investigated electron acceleration by turbulent plasmoid reconnection, described by MHD simulations, via test particle calculations. In order to avoid resolving all relevant turbulence scales down to the dissipation scales, a mean-field turbulence model is used to describe the turbulence of sub-grid scales and their effects via a turbulent electromotive force (EMF). The mean-field model describes the turbulent EMF as a function of the mean values of current density, vorticity, magnetic field as well as of the energy, cross-helicity, and residual helicity of the turbulence. We found that, mainly around X-points of turbulent reconnection, strongly enhanced localized EMFs most efficiently accelerated electrons and caused the formation of power-law spectra. Magnetic-field-aligned EMFs, caused by the turbulence, dominate the electron acceleration process. Scaling the acceleration processes to parameters of the Hermean magnetotail, electron energies up to 60 keV can be reached by turbulent plasmoid reconnection through the thermal plasma.

Distinctions of fitting within accelerated electron beam

International Nuclear Information System (INIS)

Surzhikov, A.P.; Pritulov, A.M.

1999-01-01

This report generalizes the outcomes of experimental research of the radiation and thermal processes (RTP) occurring under irradiation of compacted powders by the intensive accelerated electron flux, when the ferrite ceramics fitting takes place. Methods of dilatometric and X-ray-phase analysis, optical and electron microscopy, electrophysical and magnetic parameters measuring were used to study three basic groups of the solid-phase reactions supporting the sintering of the complex oxide with variable composition. The reactions are as follows: 1) the grain and intergranular mass transfer causing the fitting, and forming a final microstructure of a material; 2) interphase interactions enhancing the chemical homogeneity of an item; 3) interaction of a compact substance and the environmental oxygen, that is essential for maintaining the equilibrium content of the oxygen. The research activity was financed by the Russian Fundamental Research Fund

Application of polymers cross-linked by electron beam irradiation to electric wire industry

International Nuclear Information System (INIS)

Oda, Eisuke

1976-01-01

Applications of the polymers cross-linked by electron beam irradiation to electric wire industry as an example of dully developed utilization are reviewed. The report is divided into five parts, namely 1) radiation sources and irradiation processes, 2) development of crosslinking materials, 3) accumulation of electric charge and accumulation of heat, 4) examples of application, and 5) future prospect. Such a phenomenon as discharge destruction pattern (Lichtenberg figure) must be solved, when cable insulation materials are cross-linked by electron beam irradiation. The measures for preventing the discharge destruction are required, especially when the layers of polyethylene insulation for high voltage cables are irradiated. The accumulation of heat causes the troubles in foaming, degeneration and wire running of high potential cables, when the layers of insulation are thick. Effective promoters for cross-linking must be studied to reduce the radiation dose. The irradiators capable of irradiating wires uniformly are desirable. Electron beam accelerators will be used, as far as the radiation dose of 10 or more Mrad is required for cross-linking irradiation. If the dose of one tenth or less of the above value is required, gamma-ray sources (RI) are rather easily applicable than focused strong beam. The utilization of spent nuclear fuel is desirable. (Iwakiri, K.)

Evaluation of induced radioactivity in 10 MeV-Electron irradiated spices, (2)

International Nuclear Information System (INIS)

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

1994-01-01

In order to check radioactivity of beta-emmitters produced by (γ, n) reactions which could occur at energies up to 10 MeV, black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy. Beta-rays were counted using a 2π gas flow counter and a liquid scintillation counter. Any induced radioactivity could not be detected in irradiated samples. When inorganic compounds containing the nuclides in the list were artificially added in the samples and were irradiated, the β-activities were detected. From the amount of observed radioactivities of β-emmitters produced in the compounds as photonuclear products, it is concluded that the induced radioactivity in natural samples by 10 MeV-electron irradiation were far smaller than natural radioactivity from 40 K contained in the samples and, hence, its biological effects should be negligible. (author)

Electron beam irradiation effects on xanthan gum. Rheological aspects

International Nuclear Information System (INIS)

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

2001-01-01

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

Need for accelerating electrons

International Nuclear Information System (INIS)

Kerst, D.W.

1987-01-01

Photons for nuclear disintegration experiments were not abundantly available in the early days of nuclear physics, whereas accelerated ions led the way. When electrons could be accelerated into the 20--30 MeV range, they found application not only to nuclear disintegration of the elements of the periodic table but also to x-ray radiography and to deep therapy. Energies of interest for probing nuclear structure by electron scattering and for meson production followed soon after. The elementary nature of the electron has now made it a valuable tool for present day particle physics; and the synchrotron radiation, which is an obstacle for some accelerating processes, has become a much sought after source of photons for experiments at atomic structure energies

Decomposition of organic pollutants in industrial Effluent induced by advanced oxidation process with Electron beam irradiation

International Nuclear Information System (INIS)

Duarte, C.L.; Sampa, M.H.O.; Rela, P.R.; Oikawa, H.; Silveira, C.G.

2001-01-01

Advanced Oxidation Process (AOP) by electron beam irradiation induce the decomposition of pollutants in industrial effluent. Experiments were conducted using a Radiation Dynamics Electron Beam Accelerator with 1.5 MeV energy and 37 Kew power. Experiments were conducted using samples from a Governmental Wastewater Treatment Plant (WTP) that receives about 20% of industrial wastewater, with the objective of use the electrons beam technology to destroy the refractory organic pollutants. Samples from WTP main Industrial Receiver Unit influent (IRU), Coarse Bar Screens effluent (CBS), Medium Bar Screens effluent (MBS), Primary Sedimentation effluent (PS) and Final Effluent (FE), were collected and irradiated in the electron beam accelerator in a batch system. The delivered doses were 5.0kGy, 10.0kGy and 20.0kGy. The electron beam irradiation showed be efficient on destroying the organic compounds delivered in these effluents mainly chloroform, dichloroethane, methyl isobutyl ketone, benzene, toluene, xylene, phenol. The necessary dose to remove 90% of the most organic compounds from industry effluent was 20 kGy. The removal of organic compounds from this complex mixture were described by the destruction G value (Gd) that were obtained for those compounds in different initial concentration and compared with literature

Small-scale laser based electron accelerators for biology and medicine: a comparative study of the biological effectiveness

Science.gov (United States)

Labate, Luca; Andreassi, Maria Grazia; Baffigi, Federica; Basta, Giuseppina; Bizzarri, Ranieri; Borghini, Andrea; Candiano, Giuliana C.; Casarino, Carlo; Cresci, Monica; Di Martino, Fabio; Fulgentini, Lorenzo; Ghetti, Francesco; Gilardi, Maria Carla; Giulietti, Antonio; Köster, Petra; Lenci, Francesco; Levato, Tadzio; Oishi, Yuji; Russo, Giorgio; Sgarbossa, Antonella; Traino, Claudio; Gizzi, Leonida A.

2013-05-01

Laser-driven electron accelerators based on the Laser Wakefield Acceleration process has entered a mature phase to be considered as alternative devices to conventional radiofrequency linear accelerators used in medical applications. Before entering the medical practice, however, deep studies of the radiobiological effects of such short bunches as the ones produced by laser-driven accelerators have to be performed. Here we report on the setup, characterization and first test of a small-scale laser accelerator for radiobiology experiments. A brief description of the experimental setup will be given at first, followed by an overview of the electron bunch characterization, in particular in terms of dose delivered to the samples. Finally, the first results from the irradiation of biological samples will be briefly discussed.

Electron-irradiation-induced phase transformation in alumina

International Nuclear Information System (INIS)

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

2010-01-01

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

Electron accelerators: History, applications, and perspectives

Science.gov (United States)

Martins, M. N.; Silva, T. F.

2014-02-01

This paper will present an outlook on sources of radiation, focusing on electron accelerators. We will review advances that were important for the development of particle accelerators, concentrating on those that led to modern electron accelerators. Electron accelerators are multipurpose machines that deliver beams with energies spanning five orders of magnitude, and are used in applications that range from fundamental studies of particle interactions to cross-linking polymer chains in industrial plants. Each accelerator type presents specific characteristics that make it more suitable for certain applications. Our work will focus on radiation sources for medical applications, dominated by electron linacs (linear accelerators), and those used for research, field where electron rings dominate. We will outline the main technological advances that occurred in the past decades, which made possible the construction of machines fit for clinical environments. Their compactness, efficiency and reliability have been key to their acceptance in clinical applications. This outline will include advances that allowed for the construction of brighter synchrotron light sources, where the relevant beam characteristics are good optical quality and high beam current. The development of insertion devices will also be discussed, as well the development of Free Electron Lasers (FEL). We conclude the review with an outline of the new developments of electron accelerators and the expectations for Energy Recovery Linacs.

The applications of electron accelerator. Liquid, thin film and gases

International Nuclear Information System (INIS)

Khairul Zaman Hj Mohd Dahlan; Kamaruddin Hashim; Zulkafli Ghazali

2004-01-01

As indicated by the results of this study, low energy electron beam accelerator of 200 keV to 500 keV can be utilized to irradiate thin hydrogel film in the range of 60 to 500 μm thickness. However, the industrial applications of this technology will depend on its applications. For thin films, cosmetic use such as faced mask is possible. The production of sago hydrogel for cosmetic used is in the process of commercialization in Malaysia. As for electron beam treatment of industrial wastewater in particular the effluent from the textile industry is still at infancy. Further work is necessary in order to have a base line data before the commercialization is taken place. Malaysia has also embarked on the electron beam treatment of flue gases and has completed the semi-pilot scale study by using 1.0 MeV electron accelerator voltage and 400 cum flue gas generated from diesel generator. This study was conducted together with the TNB Research, the research institute belongs to the electrical power company in Malaysia. For technology transfer and commercialization, MINT is planned to promote this technology to Independent Power Producers (IPP) in Malaysia. (author)

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

International Nuclear Information System (INIS)

Ortiz, Angel V.; Nogueira, Beatriz R.; Oliveira, Vitor M.; Moura, Esperidiana A.B.

2009-01-01

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

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

Science.gov (United States)

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

2016-07-01

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

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

OpenAIRE

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

2002-01-01

The modifications to technological copper and niobium surfaces induced by 2.5 keV electron irradiation have been investigated in the context of the conditioning process occurring in particle accelerator ultra high vacuum systems. Changes in the elemental surface composition have been found using Scanning Auger Microscopy (SAM) by monitoring the carbon, oxygen and metal Auger peak intensities as a function of electron irradiation in the dose range 10-6 to 10-2 C mm-2. The surface analysis resu...

Current and future industrial application of electron accelerators in Thailand

International Nuclear Information System (INIS)

Siri-Upathum, Chyagrit

2003-01-01

Industrial applications of electron accelerators in Thailand, first introduced in 1997 for radiation sterilized products such as doctor gown, pampas, feminine napkin etc followed by installation of accelerators, one with energies at 20 MV and the other at 5 MV to produce new value added products like gem stones, topaz, tourmaline and zircon. The machines operate in pulse mode and is also used for irradiation services for food and sterilized products treatment. The need for low and medium energy accelerators in radiation technology is stressed. They are to be used for crosslinking of electrical wire and cable, heat shrinkable materials, low protein concentrated rubber latex, rubber wood furniture and parts, and silk protein degradation. The role of governmental organizations like Nuclear Research Institute (OAEP) and universities in stimulating the utilization of radiation processing in Thailand is strengthened. (S. Ohno)

Current and future industrial application of electron accelerators in Thailand

Energy Technology Data Exchange (ETDEWEB)

Siri-Upathum, Chyagrit [Chulalongkorn Univ., Faculty of Engineering, Bangkok (Thailand)

2003-02-01

Industrial applications of electron accelerators in Thailand, first introduced in 1997 for radiation sterilized products such as doctor gown, pampas, feminine napkin etc followed by installation of accelerators, one with energies at 20 MV and the other at 5 MV to produce new value added products like gem stones, topaz, tourmaline and zircon. The machines operate in pulse mode and is also used for irradiation services for food and sterilized products treatment. The need for low and medium energy accelerators in radiation technology is stressed. They are to be used for crosslinking of electrical wire and cable, heat shrinkable materials, low protein concentrated rubber latex, rubber wood furniture and parts, and silk protein degradation. The role of governmental organizations like Nuclear Research Institute (OAEP) and universities in stimulating the utilization of radiation processing in Thailand is strengthened. (S. Ohno)

Investigations of the effect of electron-beam irradiation on bacteria in sewage sludge

International Nuclear Information System (INIS)

Osterstock, G.

1976-01-01

The effect of electron beams on bacteria was investigated in 2 experimental facilities. A 400 kV electron accelerator was used to irradiate sludge quantities of 10 l and 180 l. The total bacterial count, number of coliform bacteria and, in injected sludge, the relative bacteria density of salmonella were investigated. A dose of 0.5 to 0.75 Mrad was required to reduce coliform bacteria to below the detectable level in 0.1 ml. With a dose of 1.5 Mrad salmonella were reduced by 6 orders of magnitude on the average. In addition, the dependence of the reduction in bacteria on the dose rate as well as on mixing of the irradiation material was investigated. Substantial reproduction of bacteria in digested sludge was found in all cases after the irradiation. (author)

Fixed-Target Electron Accelerators

International Nuclear Information System (INIS)

Brooks, William K.

2001-01-01

A tremendous amount of scientific insight has been garnered over the past half-century by using particle accelerators to study physical systems of sub-atomic dimensions. These giant instruments begin with particles at rest, then greatly increase their energy of motion, forming a narrow trajectory or beam of particles. In fixed-target accelerators, the particle beam impacts upon a stationary sample or target which contains or produces the sub-atomic system being studied. This is in distinction to colliders, where two beams are produced and are steered into each other so that their constituent particles can collide. The acceleration process always relies on the particle being accelerated having an electric charge; however, both the details of producing the beam and the classes of scientific investigations possible vary widely with the specific type of particle being accelerated. This article discusses fixed-target accelerators which produce beams of electrons, the lightest charged particle. As detailed in the report, the beam energy has a close connection with the size of the physical system studied. Here a useful unit of energy is a GeV, i.e., a giga electron-volt. (ne GeV, the energy an electron would have if accelerated through a billion volts, is equal to 1.6 x 10 -10 joules.) To study systems on a distance scale much smaller than an atomic nucleus requires beam energies ranging from a few GeV up to hundreds of GeV and more

Application of Electron Accelerators in Conjunction with Microwave Sources in Medical Studies

International Nuclear Information System (INIS)

Martin, D.; Craciun, G.; Manaila, E.; Ighigeanu, D.; Margaritescu, I.; Chirita, D.; Neagu, M.

2009-01-01

Electron beams (EB) are presently used, in addition to the routine conventional radiotherapy techniques, for cancer specialized therapies (intensity modulated radiation therapy [1] and total body electron irradiation [2]), the irradiation of blood and blood components, vaccine preparation, and other. Microwaves (MW) are presently used for therapeutic applications in cardiology, urology, surgery, ophthalmology, cancer therapy, and others, and for diagnostic applications such as cancer detection, organ imaging, and more [3]. The reported data show that low dose-all body irradiation with ionizing as well as with nonionizing irradiation may enhance the tumoricidal effects of radiation or chemotherapy, overcome acquired drug resistance and can stimulate certain components of the immune system that may aid in destroying cancer cells. These data suggested that application of low-dose total body EB + MW irradiation in conjunction with chemotherapy could contribute by novel effects to the cancer therapies. In view of this argument two specifically designed radiation exposure devices (REDs) were carried out for separate, successive and simultaneous irradiation with EB of 6.23 MeV and MW of 2.45 GHz in vivo (RED-vivo) and in vitro (RED-vitro) for the following medical studies: 1) The effects of low-dose EB + MW total body irradiation without/with drugs administration on the C57 BL/6 mice bearing malignant melanoma (MM); 2) The effects of separate and simultaneous MW and EB irradiation on MM cells culture without/with drugs incubation and on human blood components (proteins and cells) irradiated in samples of integral blood from healthy donors and from donors with MM. Both REDs consist of the following units: 1) An accelerated EB source: ALIN-10 electron linear accelerator of 6.23 MeV and adjustable absorbed dose rate from 0.002 Gy s-1 up to 70 Gy s-1 (built in the NILPRP, Bucharest, Romania); 2) A special designed exposure chamber that permits inside separate, successive or

Pilot-plant for NOx, SO2, HCl removal from flue-gas of municipal waste incinerator by electron beam irradiation

International Nuclear Information System (INIS)

Doi, Takeshi; Suda, Shoichi; Morishige, Atsushi; Tokunaga, Okihiro; Aoki, Yasushi; Sato, Shoichi; Komiya, Mikihisa; Hashimoto, Nobuo; Nakajima, Michihiro.

1992-01-01

A pilot-Plant for NO x , SO 2 and HCl removal from flue-gas of municipal waste incinerator by electron beam irradiation was designed and its construction at Matsudo City Waste Disposal Center was planned. The flue-gas of 1,000 Nm 3 /hr is guided from the waste incinerator flue-gas line of 30,000 Nm 3 /hr to the Pilot-Plant to be processed by spraying Ca(OH) 2 slurry (NKK-LIMAR Process) and irradiating high-energy electron beam of an accelerator. NO x , SO 2 and HCl are removed simultaneously from the flue-gas by the enhanced reaction with Ca(OH) 2 under irradiation. According to the basic research performed using a small size reactor at TRCRE of JAERI, the electron beam irradiation process was proved to be very effective for these harmful gases removal. Based on this result, the Pilot-Plant was designed for the demonstration of NO x , SO 2 and HCl removal performance using electron accelerator of maximum energy 0.95 MeV and maximum power 15 kW. The designing and planning were promoted by NKK in cooperation with JAERI and Matsudo City. (author)

Radiation facilities and irradiation technology for food irradiation

International Nuclear Information System (INIS)

Sunaga, Hiromi

2005-01-01

Progress made during these 30 years in the field of radiation treatment of food is reviewed by describing features of the process including elementary processes, quality control of the products and the dosimetric techniques widely employed. The Co-60 gamma-ray irradiation facilities to be used for radiation-sterilization of medical supplies and food preservation are presented. For electron beam irradiation, accelerators for processing with the energy from 0.3 to 10 MeV are generally employed. The electron-guns, the method of acceleration such as rectification, types of acceleration as Cockcroft-Walton, dynamitron, or linear acceleration and X-ray producing facility, with various countermeasures for safety management, are briefly explained. The concepts of dose and traceability are given. The dosimeters including reference dosimeter and routine ones with validation are explained. (S. Ohno)

Dealing with post-accelerated electrons in the ITER SINGAP accelerator

International Nuclear Information System (INIS)

Esch, H. de; Hemsworth, R.S.

2006-01-01

Electrons formed by stripping of the negative deuterium beam can be accelerated up to 960 keV in the 1 MeV SINGAP 40 A negative ion accelerator proposed by Europe for the ITER neutral beam injectors. SINGAP accelerates 1280 pre-accelerated 40 keV deuterium beamlets to 1 MeV in a single 350 mm wide gap. At the expected gas pressure of 0.03 Pa inside the accelerator, 2.7 MW of electrons are calculated to leave the accelerator and strike various beamline components, especially the neutraliser. The accelerators of the ITER injectors are designed to produce 4 '' column '' beams which pass through the 4 vertical channels of the neutraliser. Unperturbed the accelerated electrons create small, high power density, 3.3 kW/cm 2 , spots on the leading edges of the neutraliser channels, which is far in excess of their power handling capability. The hot spots arise from the overlapping of beamlets due to the bending induced by the far field of the magnetic filter in the ion source. The proposed solution bends the electrons further downwards, redistributing the power over the neutraliser floor, a vertical electron dump perpendicular to the beam axis located below the neutraliser entrance, and the neutraliser entrance. The bending is to be effected by a magnetic field transverse to the beam direction at the exit of the post-acceleration grid. This field is created by vertical columns of permanent magnets either side of each column beam. After passing between the magnet columns, the electron beams reach the electron dump with a maximum power density of 2.1 kW/cm 2 . The peak power density on the neutraliser entrance is 1.35 kW/cm 2 and on the neutraliser floor 0.82 kW/cm 2 . Electron backscattering would reduce all the numbers by 20%. To further reduce the average power density seen by the beamline components it is proposed to sweep the electron beam in an oscillatory fashion. It is suggested that a failsafe, inexpensive, way is to use a power supply with a ripple of ± 10% to

An Economic Analysis for using Gamma and Electron Irradiation Technology in Preservation of Wheat in Egypt

International Nuclear Information System (INIS)

El-Gameel, E.A.

2011-01-01

The present study discusses the economic analysis of wheat irradiation in Egypt. This study was divided into four sections; the first section included the arrangement of the equation of simple regression foretelling the future of wheat import and national production. The second section include the financial analysis of electron beam accelerator facility, the third section discusses the financial analysis of gamma irradiation facility and the fourth section discusses the national return of wheat irradiation

Laser-driven electron accelerators

International Nuclear Information System (INIS)

Palmer, R.B.

1981-01-01

The following possibilities are discussed: inverse free electron laser (wiggler accelerator); inverse Cerenkov effect; plasma accelerator; dielectric tube; and grating linac. Of these, the grating acceleraton is considered the most attractive alternative

High-energy inverse free-electron laser accelerator

International Nuclear Information System (INIS)

Courant, E.D.; Pellegrini, C.; Zakowicz, W.

1985-01-01

We study the inverse free electron laser (IFEL) accelerator and show that it can accelerate electrons to the few hundred GeV region with average acceleration rates of the order of 200 meV/m. Several possible accelerating structures are analyzed, and the effect of synchrotron radiation losses is studied. The longitudinal phase stability of accelerated particles is also analyzed. A Hamiltonian description, which takes into account the dissipative features of the IFEL accelerator, is introduced to study perturbations from the resonant acceleration. Adiabatic invariants are obtained and used to estimate the change of the electron phase space density during the acceleration process

Calibration of a silicon semiconductor detecter using a 2 MeV electron accelerator beam

International Nuclear Information System (INIS)

Fleurot, N.; Gouard, P.; Mazataud, E.; Nail, M.; Savy, C.; Bayer, C.; Cauchois, Y.; Kherouf, R.; Mathieu, D.

1981-01-01

This paper describes the current mode calibration, carried out on a 2 MeV electron accelerator, of PIN detectors involved in electron spectrum measurements for laser-matter interaction experiments. A theoretical analysis simulating the interaction between the incident electrons and the irradiated medium has been carried out using the FOTELEC code. It accounts well for the experimental results giving a reasonable value for the mean electron-hole pair formation energy when back-scattering corrections are included. This work provides the transfer function data required for a plasma diagnostic spectrometer. (orig.)

Ultrashort megaelectronvolt positron beam generation based on laser-accelerated electrons

Science.gov (United States)

Xu, Tongjun; Shen, Baifei; Xu, Jiancai; Li, Shun; Yu, Yong; Li, Jinfeng; Lu, Xiaoming; Wang, Cheng; Wang, Xinliang; Liang, Xiaoyan; Leng, Yuxin; Li, Ruxin; Xu, Zhizhan

2016-03-01

Experimental generation of ultrashort MeV positron beams with high intensity and high density using a compact laser-driven setup is reported. A high-density gas jet is employed experimentally to generate MeV electrons with high charge; thus, a charge-neutralized MeV positron beam with high density is obtained during laser-accelerated electrons irradiating high-Z solid targets. It is a novel electron-positron source for the study of laboratory astrophysics. Meanwhile, the MeV positron beam is pulsed with an ultrashort duration of tens of femtoseconds and has a high peak intensity of 7.8 × 1021 s-1, thus allows specific studies of fast kinetics in millimeter-thick materials with a high time resolution and exhibits potential for applications in positron annihilation spectroscopy.

Pulse radiolysis with (sub) nanosecond time resolution using a 3 MV electron accelerator

International Nuclear Information System (INIS)

Luthjens, L.H.

1986-01-01

In this thesis the development of equipment for pulse radiolysis is described and the application of the technique to time-resolved measurements of the fluorescence emission of excited states formed after irradiation of some alkanes is dealt with. A review is given of the development of the pulsed 3MV Van de Graaf electron accelerator for the generation of subnanosecond electron beam pulses and of the development of the equipment for optical detection as accomplished by the author. The initial stage of a further development for shorter pulses and higher time resolution is briefly discussed. A collection of papers on the development of apparatus and a collection of papers dealing with the results obtained from measurements of the fluorescence of excited states, formed by the recombination of electrons and ions in irradiated alkanes such as cyclohexane and the decalines, are included. (Auth.)

Application of electron beams irradiation in science and industry

International Nuclear Information System (INIS)

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

1996-01-01

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

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

CERN Document Server

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

2016-01-01

Electronic components must be tested to ensure reliable performance in high radiation environments such as Hi-Limu LHC and space. We propose a defocusing beam line to perform proton irradiation tests in Turkey. The Turkish Atomic Energy Authority SANAEM Proton Accelerator Facility was inaugurated in May 2012 for radioisotope production. The facility has also an R&D room for research purposes. The accelerator produces protons with 30 MeV kinetic energy and the beam current is variable between View the MathML source10μA and View the MathML source1.2mA. The beam kinetic energy is suitable for irradiation tests, however the beam current is high and therefore the flux must be lowered. We plan to build a defocusing beam line (DBL) in order to enlarge the beam size, reduce the flux to match the required specifications for the irradiation tests. Current design includes the beam transport and the final focusing magnets to blow up the beam. Scattering foils and a collimator is placed for the reduction of the beam ...

First symposium accelerated partial breast irradiation

International Nuclear Information System (INIS)

2012-01-01

The First symposium accelerated partial breast irradiation, was organized by the Marie Curie Foundation, between the 14 to 16 june 2012, in the Cordoba city of Argentina. In this event were presented some papers on the following topics: radiotherapy in breast cancer; interaction between systemic treatments and radiotherapy; interstitial brachytherapy.

Direct nanopatterning of polymer/silver nanoblocks under low energy electron beam irradiation.

Science.gov (United States)

El Mel, Abdel-Aziz; Stephant, Nicolas; Gautier, Romain

2016-10-06

In this communication, we report on the growth, direct writing and nanopatterning of polymer/silver nanoblocks under low energy electron beam irradiation using a scanning electron microscope. The nanoblocks are produced by placing a droplet of an ethylene glycol solution containing silver nitrate and polyvinylpyrrolidone diluted in ethanol directly on a hot substrate heated up to 150 °C. Upon complete evaporation of the droplet, nanospheres, nano- and micro-triangles and nanoblocks made of silver-containing polymers, form over the substrate surface. Considering the nanoblocks as a model system, we demonstrate that such nanostructures are extremely sensitive to the e-beam extracted from the source of a scanning electron microscope operating at low acceleration voltages (between 5 and 7 kV). This sensitivity allows us to efficiently create various nanopatterns (e.g. arrays of holes, oblique slits and nanotrenches) in the material under e-beam irradiation. In addition to the possibility of writing, the nanoblocks revealed a self-healing ability allowing them to recover a relatively smooth surface after etching. Thanks to these properties, such nanomaterials can be used as a support for data writing and erasing on the nanoscale under low energy electron beam irradiation.

Compact multi-energy electron linear accelerators

International Nuclear Information System (INIS)

Tanabe, E.; Hamm, R.W.

1985-01-01

Two distinctly different concepts that have been developed for compact multi-energy, single-section, standing-wave electron linear accelerator structures are presented. These new concepts, which utilize (a) variable nearest neighbor couplings and (b) accelerating field phase switching, provide the capability of continuously varying the electron output energy from the accelerator without degrading the energy spectrum. These techniques also provide the means for continuously varying the energy spectrum while maintaining a given average electron energy, and have been tested successfully with several accelerators of length from 0.1 m to 1.9 m. Theoretical amd experimental results from these accelerators, and demonstrated applications of these techniques to medical and industrial linear accelerator technology will be described. In addition, possible new applications available to research and industry from these techniques are presented. (orig.)

Current state and prospects of industrial application of electron beam irradiation

International Nuclear Information System (INIS)

Washio, Masakazu

2000-01-01

This paper reviewed the low energy, medium energy, and high energy accelerators used for the industrial application of electron beams. Next, it described the absorption of electron beam energy, distribution of the absorbed dose of electron beams in a substance, and the basis of electron beam reaction. Furthermore, as the industrial application examples of electron beams, it briefly described about the reforming and curing of polymers, irradiation effect of inorganic material (characteristic control of semiconductors), and sterilization. Regarding curing, as examples using mainly low energy electron beams (300 keV or below), this paper briefly explained the manufacture of thermosensitive recording materials, electron beam cured silicone for release papers, tunnel metal interior finishing board, high gloss - high smooth paper. Finally, it looked at latest trends and prospects of electron beam generators. (A.O.)

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

International Nuclear Information System (INIS)

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

1991-01-01

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

Influence of electron beam Irradiation on PP/Piassava fiber composite prepared by melt extrusion process

International Nuclear Information System (INIS)

Gomes, Michelle G.; Ferreira, Maiara S.; Oliveira, Rene R.; Silva, Valquiria A.; Teixeira, Jaciele G.; Moura, Esperidiana A.B.

2013-01-01

In the latest years, the interest for the use of natural fibers in materials composites polymeric has increased significantly due to their environmental and technological advantages. Piassava fibers (Attalea funifera) have been used as reinforcement in the matrix of thermoplastic and thermoset polymers. In the present work (20%, in mass), piassava fibers with particle sizes equal or smaller than 250 μm were incorporated in the polypropylene matrix (PP) no irradiated and polypropylene matrix containing 10 % and 30 % of polypropylene treated by electron-beam radiation at 40 kGy (PP/PPi/Piassava). The composites PP/Piassava and PP/PPi/Piassava were prepared by using a twin screw extruder, followed by injection molding. The composite material samples obtained were treated by electron-beam radiation at 40 kGy, using a 1.5 MeV electron beam accelerator, at room temperature, in presence of air. After irradiation treatment, the irradiated and non-irradiated specimens tests samples were submitted to thermo-mechanical tests, melt flow index (MFI), sol-gel analysis, X-Ray diffraction (XRD) and scanning electron microscopy (SEM). (author)

Structural changes induced by electron irradiation

International Nuclear Information System (INIS)

Koike, J.; Pedraza, D.F.

1993-01-01

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

Investigations of the effect of electron-beam irradiation on bacteria in sewage sludge

International Nuclear Information System (INIS)

Osterstock, G.

1976-01-01

The effect of electron beams on bacteria was investigated in 2 experimental facilities. A 400 kV electron accelerator was used to irradiate sludge quantities of 10 l and 180 l. The total bacterial count, the number of coliform bacteria and, in injected sludge, the relative bacteria density of salmonella were investigated. A dose of 0.5 to 0.75 Mrad was required to reduce coliform bacteria to below the detectable level in 0.1 ml. With a dose of 1.5 Mrad salmonella were reduced by 6 orders of magnitude on the average. In addition, the dependence of the reduction in bacteria on the dose rate as well as on mixing of the irradiated material was investigated. Substantial reproduction of bacteria in digested sludge was found in all cases after the irradiation. (orig./MG) [de

Alanine-ESR dosimeter: application for dosimetry in industrial electron beam accelerator

International Nuclear Information System (INIS)

Murali, S.; Venkataramani, R.; Pushparaja; Sarma, K.S.S.; Natarajan, V.; Sastry, M.D.

2000-01-01

The feasibility of DL-α-alanine, as ESR dosimeter in powder form, was examined under the conditions of pulse electron accelerator used as an industrial irradiator. The investigations were carried out to examine the following aspects: (i) Alanine-ESR dose response in irradiator characteristics viz. various beam energies, beam currents, product conveying speeds, (ii) linearity of dose response of irradiated alanine signal for suitable range, (iii) dose uniformity of the irradiated samples and (iv) depth dose measurements using alanine powder dosimeters sandwiched between polyethylene layers. Experiments were carried out by varying some of the irradiator parameters at mobile mode of the conveyor (product under movement) and also at stationary mode for different EB energies and pulse rates. For estimation of EB dose, signal intensities of gamma irradiated DL--alanine powder calibrated with Fricke dosimetry have been used. Feasibility of application of alanine ESR dosimeter for low dose measurement down to 350 Gy has been experimentally established. The present studies show that under variable operating conditions of irradiator, alanine ESR dosimetry is suitable for dosimetric applications from low dose (350 Gy) to high dose (53 kgy). (author)

Disinfection of wastewaters: high-energy electron vs gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

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

1993-07-01

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

Ion acceleration in modulated electron beams

International Nuclear Information System (INIS)

Bonch-Osmolovskij, A.G.; Dolya, S.N.

1977-01-01

A method of ion acceleration in modulated electron beams is considered. Electron density and energy of their rotational motion are relatively low. However the effective ion-accelerating field is not less than 10 MeV/m. The electron and ion numbers in an individual bunch are also relatively small, although the number of produced bunches per time unit is great. Some aspects of realization of the method are considered. Possible parameters of the accelerator are given. At 50 keV electron energy and 1 kA beam current a modulation is realized at a wave length of 30 cm. The ion-accelerating field is 12 MeV/m. The bunch number is 2x10 3 in one pulse at a gun pulse duration of 2 μs. With a pulse repetition frequency of 10 2 Hz the number of accelerated ions can reach 10 13 -10 14 per second

Use of accelerators in the national economy

International Nuclear Information System (INIS)

Skrinskij, A.

1984-01-01

Accelerators generating beams of accelerated particles are the basic component of apparatus used in irradiation technologies. One of the basic trends in irradiation is the improvement of materials, mainly polyethylene and other plastics. Irradiation with accelerated electrons improves their mechanical properties and chemical and heat resistance. Accelerated beams are also used in cement production and in grain disinfestation. The use is being developed of synchrotron radiation for rapid analysis of mineral samples, the manufacture of integrated circuits and for other applications. (Ha)

Dose estimation in low-energy electron beam irradiation for industrial purposes

International Nuclear Information System (INIS)

Kijima, Toshiyuki; Nakase, Yoshiaki.

1997-03-01

A Monte Carlo method for the passage of electrons based on a single scattering model is developed, in which the relativistic correction has been taken into accounted. A code based on this method is operable on personal computers, and has been applied to analyze electron behavior in a layered system consisting Ti as an accelerator window, air, cellulose triacetate (CTA) and backing material irradiated by mainly 300 keV electrons. The energy spectra and the angular distributions of electrons on CTA surface as well as depth-dose distributions of energy deposition in the CTA for various backing materials have been obtained. Some of these results are compared with experimentals, and showed fairly good agreement. (author). 322 refs

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

International Nuclear Information System (INIS)

Tokunaga, Okihiro; Arai, Hidehiko

1994-01-01

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

Femtosecond pulse radiolysis based on photocathode electron accelerator

International Nuclear Information System (INIS)

Yoshida, Y.; Yang, Jinfeng; Kondoh, T.; Kozawa, T.; Tagawa, S.

2006-01-01

Pulse radiolysis is a powerful tool for studying chemical kinetics and primary processes or reactions of radiation chemistry. In the pulse radiolysis, a short electron beam, which is almost produced by radio-frequency (RF) electron linear accelerator with energy from a few MeV to a few tens MeV, is used as an irradiative source. The electron-induced reactions or phenomena in matter are analyzed by a short-pulse analyzing light (e.g. synchronized lasers) with the time-resolved stroboscopic technique. The time resolution of pulse radiolysis is not only dependent on the electron bunch length, the analyzing light pulse width, the time jitter between the electron bunch and the analyzing light, but also determined by degradation due to the velocity difference between light and the electron in the sample because of the refractive index. In order to improve the time resolution into femtosecond time region, we have develop a new pulse radiolysis based on a concept of 'Equivalent Velocity Spectroscopy (EVS)' to avoid the degradation of the time resolution caused by the velocity difference between the light and the electron beam in sample. In EVS as shown in Fig.1, a femtosecond electron beam produced by a photocathode electron linear accelerator was used, and a synchronized femtosecond laser was used as the analyzing light source. The electron beam and the laser light were injected into sample with an angle (θ), which is determined by the refractive index (n) of the sample. The electron bunch was also rotated with a same angle to make an overlap of the electron bunch with the laser pulse. The degradation of the time resolution caused by the velocity difference between the light and the electron beam can be calculated as g(L)=L[n/c-1/(vcos θ)], where L is the optical path length and v is the velocity of the electron in sample (we can assume v=c for a few tens MeV electron beam).We can thus obtained g(L)=0 by adjusting the incident angle to cos θ=1/n. However, the rotation

Structural and electrical properties of polycrystalline CdSe thin films, before and after irradiation with 6 MeV accelerated electrons

International Nuclear Information System (INIS)

Ion, L.; Antohe, V.A.; Tazlaoanu, C.; Antohe, S.; Scarlat, F.

2004-01-01

Structural and electrical properties of polycrystalline CdSe thin films irradiated with high-energy electrons are analyzed. The samples were prepared by vacuum deposition of CdSe powder onto optical glass substrate. Their structure and the temperature dependence of the electrical resistance were determined, both before and after irradiation with 6 MeV electrons at fluencies up to 10 16 electrons/cm 2 . There were no measurable changes in the crystalline structure of the films after irradiation. Electrical properties are controlled by the defect level of donor type, possibly a selenium vacancy, with two ionizing states having ionization energies of about 0.40 eV and 0.22 eV, respectively. The major effect of the irradiation is to increase significantly the concentration of these defects. (authors)

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).

A study on radiation treatment of wastewater using an electron accelerator

International Nuclear Information System (INIS)

Hashimoto, Shoji

1982-02-01

A study on radiation oxidation treatment of refractory or toxic wastewater using an electron accelerator was carried out from the viewpoint of reaction engineering. For the process using electron beams, oxygen supply to the penetration range of electron (reaction zone) where the dose rate is extremely high, is significantly important. A concentric dual-tube-type bubbling column reactor was shown to be most suitable to maintain the dissolved oxygen at a high concentration. Rate expressions of pollutant reduction and oxygen consumption in the reactor were derived. The efficiency of active species utilization for oxidation, phi, was defined and shown to be an important design parameter. A new wastewater treatment system (Electron Accelerator-Dual tube Bubbling Reactor system) was proposed, and successfully demonstrated for the treatment of wastewater involving dyes and phenol. The dissolved oxygen was maintained at a high concentration by using this type of reactor for the high dose rate irradiation. phi was obtained as a function of dissolved oxygen concentration for the dye solution and was also obtained as functions of the oxygen concentration and dose rate for the phenol solution. By these experimental results, the effectiveness of EA-DBR system was proved. (author)

Initial dosimetric experience using simple three-dimensional conformal external-beam accelerated partial-breast irradiation

International Nuclear Information System (INIS)

Taghian, Alphonse G.; Kozak, Kevin R.; Doppke, Karen P.; Katz, Angela; Smith, Barbara L.; Gadd, Michele; Specht, Michelle; Hughes, Kevin; Braaten, Kristina; Kachnic, Lisa A.; Recht, Abram; Powell, Simon N.

2006-01-01

Purpose: Several accelerated partial-breast irradiation (APBI) techniques are being investigated in patients with early-stage breast cancer. We present our initial experience using three-dimensional conformal radiation therapy (3D-CRT). Methods and Materials: Sixty-one patients with tumors of 2 cm or less and negative axillary nodes were treated with 3D-CRT accelerated partial-breast irradiation (APBI) between August 2003 and March 2005. The prescribed radiation dose was 32 Gy in 4-Gy fractions given twice daily. Efforts were made to minimize the number of beams required to achieve adequate planning target volume (PTV) coverage. Results: A combination of photons and electrons was used in 85% of patients. A three-field technique that consisted of opposed, conformal tangential photons and enface electrons was employed in 43 patients (70%). Nine patients (15%) were treated with a four-field arrangement, which consisted of three photon fields and enface electrons. Mean PTV volumes that received 100%, 95%, and 90% of the prescribed dose were 93% ± 7%, 97% ± 4%, and 98% ± 2%, respectively. Dose inhomogeneity exceeded 10% in only 7 patients (11%). Mean doses to the ipsilateral lung and heart were 1.8 Gy and 0.8 Gy, respectively. Conclusions: Simple 3D-CRT techniques of APBI can achieve appropriate PTV coverage while offering significant normal-tissue sparing. Therefore, this noninvasive approach may increase the availability of APBI to patients with early-stage breast cancer

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

Energy Technology Data Exchange (ETDEWEB)

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

2014-10-01

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

Analysis of the power system from an electron beam accelerator and the correlation with the theoretical dosimetry for radiation processing

Energy Technology Data Exchange (ETDEWEB)

Somessari, Samir Luiz; Somessari, Elizabeth S. Ribeiro; Silveira, Carlos Gaia da; Calvo, Wilson Aparecido Parejo, E-mail: somessar@ipen.br, E-mail: esomessa@ipen.br, E-mail: cgsilvei@ipen.br, E-mail: wapcalvo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

Dynamitron DC1500/25/04 type electron beam accelerator (EBA), model JOB 188, was manufactured by IBA Industrial (Radiation Dynamics, Inc.) and installed at IPEN/CNEN-SP in 1978. The technical specifications of the EBA are: energy 0.5 to 1.5 MeV; beam current: 0.3 to 25.0 mA; beam scanning: 60 to 120 cm; beam width: 25.4 mm and frequency: 100 Hz. Nowadays, this accelerator has been used for innumerable applications, such as: for sterilization of medical, pharmaceutical and biological products; treatment of industrial and domestic effluents and sludge; preservation and disinfestation of foods and agricultural products; lignocellulosic material irradiation as a pre-treatment to produce ethanol bio-fuel; decontamination of pesticide packing; solid residues remediation; organic compounds removal from wastewater; treatment of effluent from petroleum production units; crosslinking of foams, wires and electric cables; composite and nanocomposite materials and carbon fibers irradiation; irradiated grafting ion-exchange membranes for fuel cells application; natural polymers and multilayer packages irradiation, and biodegradable blends production. The energy of the electron beam is calculated as a function of the current in the accelerator high-voltage divisor, taking into account the thickness and density of the material to be irradiated. This energy is calculated considering the electron through the entire material and the distance from the titanium foil window, so that the absorbed doses at the point of entrance and exit are equivalent on the material. The dose is directly proportional to the beam current and the exposure time of the material under the electron beam and inversely proportional to the scan width. The aim of this paper is to analyze the power system parameters of the EBA Dynamitron DC1500/25/04 accelerator, such as, voltage and root-mean-square (RMS) current in the oscillator system, high voltage generator and waveform, using software developed in the

Analysis of the power system from an electron beam accelerator and the correlation with the theoretical dosimetry for radiation processing

International Nuclear Information System (INIS)

Somessari, Samir Luiz; Somessari, Elizabeth S. Ribeiro; Silveira, Carlos Gaia da; Calvo, Wilson Aparecido Parejo

2013-01-01

Dynamitron DC1500/25/04 type electron beam accelerator (EBA), model JOB 188, was manufactured by IBA Industrial (Radiation Dynamics, Inc.) and installed at IPEN/CNEN-SP in 1978. The technical specifications of the EBA are: energy 0.5 to 1.5 MeV; beam current: 0.3 to 25.0 mA; beam scanning: 60 to 120 cm; beam width: 25.4 mm and frequency: 100 Hz. Nowadays, this accelerator has been used for innumerable applications, such as: for sterilization of medical, pharmaceutical and biological products; treatment of industrial and domestic effluents and sludge; preservation and disinfestation of foods and agricultural products; lignocellulosic material irradiation as a pre-treatment to produce ethanol bio-fuel; decontamination of pesticide packing; solid residues remediation; organic compounds removal from wastewater; treatment of effluent from petroleum production units; crosslinking of foams, wires and electric cables; composite and nanocomposite materials and carbon fibers irradiation; irradiated grafting ion-exchange membranes for fuel cells application; natural polymers and multilayer packages irradiation, and biodegradable blends production. The energy of the electron beam is calculated as a function of the current in the accelerator high-voltage divisor, taking into account the thickness and density of the material to be irradiated. This energy is calculated considering the electron through the entire material and the distance from the titanium foil window, so that the absorbed doses at the point of entrance and exit are equivalent on the material. The dose is directly proportional to the beam current and the exposure time of the material under the electron beam and inversely proportional to the scan width. The aim of this paper is to analyze the power system parameters of the EBA Dynamitron DC1500/25/04 accelerator, such as, voltage and root-mean-square (RMS) current in the oscillator system, high voltage generator and waveform, using software developed in the

Linear accelerator: a reproducible, efficacious and cost effective alternative for blood irradiation.

Science.gov (United States)

Shastry, Shamee; Ramya, B; Ninan, Jefy; Srinidhi, G C; Bhat, Sudha S; Fernandes, Donald J

2013-12-01

The dedicated devices for blood irradiation are available only at a few centers in developing countries thus the irradiation remains a service with limited availability due to prohibitive cost. To implement a blood irradiation program at our center using linear accelerator. The study is performed detailing the specific operational and quality assurance measures employed in providing a blood component-irradiation service at tertiary care hospital. X-rays generated from linear accelerator were used to irradiate the blood components. To facilitate and standardize the blood component irradiation, a blood irradiator box was designed and fabricated in acrylic. Using Elekta Precise Linear Accelerator, a dose of 25 Gy was delivered at the centre of the irradiation box. Standardization was done using five units of blood obtained from healthy voluntary blood donors. Each unit was divided to two parts. One aliquot was subjected to irradiation. Biochemical and hematological parameters were analyzed on various days of storage. Cost incurred was analyzed. Progressive increase in plasma hemoglobin, potassium and lactate dehydrogenase was noted in the irradiated units but all the parameters were within the acceptable range indicating the suitability of the product for transfusion. The irradiation process was completed in less than 30 min. Validation of the radiation dose done using TLD showed less than ± 3% variation. This study shows that that the blood component irradiation is within the scope of most of the hospitals in developing countries even in the absence of dedicated blood irradiators at affordable cost. Copyright © 2013 Elsevier Ltd. All rights reserved.

Electron Acceleration in Supernovae and Millimeter Perspectives

Directory of Open Access Journals (Sweden)

Keiichi Maeda

2014-12-01

Full Text Available Supernovae launch a strong shock wave by the interaction of the expanding ejecta and surrounding circumstellar matter (CSM. At the shock, electrons are accelerated to relativistic speed, creating observed synchrotron emissions in radio wavelengths. In this paper, I suggest that SNe (i.e., < 1 year since the explosion provide a unique site to study the electron acceleration mechanism. I argue that the eciency of the acceleration at the young SN shock is much lower than conventionally assumed, and that the electrons emitting in the cm wavelengths are not fully in the Diffusive Shock Acceleration (DSA regime. Thus radio emissions from young SNe record information on the yet-unresolved 'injection' mechanism. I also present perspectives of millimeter (mm observations of SNe - this will provide opportunities to uniquely determine the shock physics and the acceleration efficiency, to test the non-linear DSA mechanism and provide a characteristic electron energy scale with which the DSA start dominating the electron acceleration.

Electron trapping during irradiation in reoxidized nitrided oxide

International Nuclear Information System (INIS)

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

1993-01-01

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

Mechanistic insights into the room temperature transitions of polytetrafluoroethylene during electron-beam irradiation

Science.gov (United States)

Fu, Congli; Yu, Xianwei; Zhao, Xiaofeng; Wang, Xiuli; Gu, Aiqun; Xie, Meiju; Chen, Chen; Yu, Zili

2017-11-01

In order to recognize the characteristic thermal transitions of polytetrafluoroethylene (PTFE) occurring at 19 °C and 30 °C, PTFE is irradiated on electron beam accelerator at room temperature and analyzed by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results suggest that the two transition temperatures decrease considerably with increasing irradiation doses. Based on the results of structural analysis, the decrease of the two transition temperatures is supposed to be highly relevant to the structural changes. In particular, the content and structure of the side groups generated in PTFE are responsible for the variations of the two thermal transitions after irradiation, offering fundamental insights into the reaction mechanisms of PTFE during irradiation.

Electron beam irradiation: a novel technology to enhance the quality of soybean seeds

International Nuclear Information System (INIS)

Bhalla, Shashi; Srinivasan, K.; Singh, Subadas; Thakur, Manju; Sharma, S.K.; Pramod, R.; Dwivedi, J.; Bapna, S.C.

2010-01-01

Soybean seeds, rich in protein and oil, maintain their germinability only for short durations under ambient conditions. Loss of viability of stored seeds often hampers soybean production in harsh environments worldwide. Physiological factors favored by high temperature and high moisture content accelerate the seed deterioration in the tropics. Several chemical and physical treatments are being used to enhance quality. Irradiation is a novel technology for food preservation and is gaining importance all over the world. Low doses of irradiation bring about improvement in quality of food/seeds, which can be beneficial in several ways. Electron Beam (EB) irradiation is a new approach in this area. The objective of present study was to investigate the effect of EB irradiation in enhancing the quality of low vigour soybean seeds

Picosecond, single pulse electron linear accelerator

International Nuclear Information System (INIS)

Kikuchi, Riichi; Kawanishi, Masaharu

1979-01-01

The picosecond, single pulse electron linear accelerators, are described, which were installed in the Nuclear Engineering Laboratory of the University of Tokyo and in the Nuclear Radiation Laboratory of the Osaka University. The purpose of the picosecond, single pulse electron linear accelerators is to investigate the very short time reaction of the substances, into which gamma ray or electron beam enters. When the electrons in substances receive radiation energy, the electrons get high kinetic energy, and the energy and the electric charge shift, at last to the quasi-stable state. This transient state can be experimented with these special accelerators very accurately, during picoseconds, raising the accuracy of the time of incidence of radiation and also raising the accuracy of observation time. The outline of these picosecond, single pulse electron linear accelerators of the University of Tokyo and the Osaka University, including the history, the systems and components and the output beam characteristics, are explained. For example, the maximum energy 30 -- 35 MeV, the peak current 1 -- 8 n C, the pulse width 18 -- 40 ps, the pulse repetition rate 200 -- 720 pps, the energy spectrum 1 -- 1.8% and the output beam diameter 2 -- 5 mm are shown as the output beam characteristics of the accelerators in both universities. The investigations utilizing the picosecond single pulse electron linear accelerators, such as the investigation of short life excitation state by pulsed radiation, the dosimetry study of pulsed radiation, and the investigation of the transforming mechanism and the development of the transforming technology from picosecond, single pulse electron beam to X ray, vacuum ultraviolet ray and visual ray, are described. (Nakai, Y.)

Structure and properties of binary polystyrene-epoxy acrylate oligomer mixtures irradiated by electron beams

International Nuclear Information System (INIS)

Lomonosova, N.V.

1995-01-01

The change in the structure of oriented polymer-oligomer systems based on polystyrene (PS) with M > 10 6 and epoxy acrylate oligomers (aliphatic and aromatic) under irradiation by accelerated electrons was studied using birefringence, isometric heating, IR dichroism, and thermooptical analysis. Mechanical properties of these systems were investigated. It was found that, by adding aliphatic epoxy acrylate to PS and further irradiating this mixture, one can obtain both isotropic and oriented composites with higher strengths, elasticity moduli, and glass transition temperatures

Construction of electron accelerator for studying secondary emission in dielectric materials

International Nuclear Information System (INIS)

Hessel, R.

1990-01-01

An acelerator for the generation of low energy electrons (in the 0.4 to 20 keV range) was constructed. The accelerator is equipped with some devices especially designed for the investigation of the electrical properties of electron-irradiated dielectrics. In this work we have employed it for the study of the secondary electron emission of irradiated polymers. Reference is made to a method proposed by H. von Seggern (IEEE Trans. Nucl. Sci. NS-32, p.1503 (1985)] which was intended for the determination of the electron emission yield especially between the two cross-over points in a single run, here called the dynamical method. We have been able to prove that, contrary to expectation, this method does not give correct results over the entire emission curve. Rather it gives yield values which are too low by 25% in the region where the emission exhibits a maximum, due to the interaction between the electron emission process and the positive surface charge of the dielectric. However the method needs not to be dismissed entirely. As it is, it can be used advantageously for the precise determination of the energy of the second cross-over point. In addition, with the same set up, the method could be improved by replacing the continuous irradiation of the sample by a pulsed irradiation, leading to results essentially the same as those shown in the literature. Finally analysing the process of interaction between the positive charge of the dielectric and the mechanism of electron emission in several situations, we were able: I) to determine the maximum value and the average value of the escape depth of the emitted electrons; II) for a sample with a net positive charge, to show that the positive charge resides very near the surface of incidence; III) for a sample with a net negative charge, to show that the positive charge also resides near the surface while the (prevalent) negative charge resides in the bulk of the material. (author)

Multibeam electron-ion accelerator with the energy of up to 1.5 MeV/charge

International Nuclear Information System (INIS)

Baranov, I.A.; Devyatko, N.N.; Obnorskij, V.V.; Trofimenko, S.M.; Shilov, V.P.; Ehjsmont, V.P.; Auslender, V.L.; Lazarev, V.N.; Panfilov, A.D.; Polyakov, V.A.

1979-01-01

Basic design peculiarities and parameters of multi-beam pulse linear accelerator for using as ion synchrotron injector, and simultaneously, as electron accelerator for radiation investigations are given. Cylindrical steel container, inside of which a coaxial resonator with a drift tube is placed, is the basis of the accelerator. Maximum energy of protons amounts to 1.5 MeV. Beam intensities of accelerated nucleus from carbon to argon are in the range of 10 11 -10 10 particles, accordingly. Main parameters of accelerated particle beam are the following: the energy - 0.2-1.3 MeV, m - 1current A,0m- 1 mean power W,0-12 kW- 1 beam diameter cm. The accelerator is equipped with a system of quasi-circular scanning for homogeneous irradiation of object surfaces [ru

Electron acceleration by CO/sub 2/ laser

International Nuclear Information System (INIS)

Fujita, H.; Kitagawa, Y.; Daido, H.

1986-01-01

Experiments on electron acceleration have been performed by LEKKO VIII CO/sub 2/ laser system. The laser light was focused by an off-axis parabolic mirror with the F-number of 1.5 and irradiated to thin foil and pipe targets in order to obtain uniform underdense plasmas. Energy spectrum of electrons was measured by an electron spectrometer in the range of 0.3-1.1 MeV. In the single frequency case, electrons up to 1 MeV were observed in the direction of the laser axis for the laser intensity above 1.6 x 10/sup 14/ W/cm/sup 2/ which was equal to the estimated threshold for forward Raman scattering. Amount of high energy electrons depended on the interaction length and the background hot electron temperature. More electrons could resonate with the plasma wave for the higher hot electron temperature. This was confirmed by particle simulation. In most experiments, the plasma density was estimated of about 0.1 n/sub c/. When the plasma density was reduced to 0.01 n/sub c/ using pre-pulse, high energy electrons were not observed because of the low background hot electron temperature and the higher instability threshold. In the two frequency case, energetic electron beam injection is planned for efficient coupling with fast plasma wave. Pipe target seems to be hopeful because 1) the laser light is confined by the plasma fiber and 2) the phase velocity of the plasma wave is controlled by the transverse mode

Bacterial effect of accelerated electrons on several pathogens

International Nuclear Information System (INIS)

Butaev, M.K.; Bulkhanov, R.U.; Ryasnyanskii, I.V.; Mirzaev, B.Sh.; Safarov, A.N.; Suleymanov, R.D.

2006-01-01

colibacterillesis and salmonellosis of calves' were developed in RIVU. By widening the application field of developed radiation biotechnology the 'Polyvalent vaccine against pasteurellesis, salmonellosis and colibacterillesis of farm animals' was created in recent years. The mentioned radio vaccines were successfully tested in laboratory and working environment and are widely used in veterinary practice in the farms of the Republic of Uzbekistan [3].For further broadening of the possibility to use the radiation biotechnology and to enrich the native arsenal of veterinary bio medication, it is presently planned to conduct large-scale research on the use of accelerated electrons (AE) to obtain in perspective new preventive materials. Several results of the beginning stage of this research are given in the present report.The suspensions of pathogenic strains of pasteurellesis, salmonellosis and Escherichia Coli strains were exposed to irradiation by accelerated electrons of microtron MT-22C. Taking into account the slightly higher resistance of bacteria against irradiation by accelerated electrons as compared to gamma-irradiation, the doses from 400 to 1100 kRad were used. At this, the special attention was paid to control the distribution of linear density of the current in scanning of AE beam, the distribution of linear density of the current in perpendicular scanning of AE beam and the value of absorbed dose. The studies showed that at AE irradiation by 400 kRad dose the bacterial survival rate is about 10 %, at 500 kRad-2-3 %, 600 kRad- less than 1 %. At the dose of 800 kRad only isolated colonies of bacteria survived. At AE irradiation by 900 kRad- 1.1 MRad dose, there was no increase the growth of bacteria's number. Since these data were obtained at the multiple repetition of results, it can be supposed that the minimal absolute devitalizing AE irradiation dose of bacteria lies in the region 0.9-1.0 MRad. At this, some inter-species and even intra species peculiarities in the

Studies of dislocation loops produced by irradiation of ZnO in a high-voltage electron microscope

International Nuclear Information System (INIS)

Yoshiie, T.; Iwanaga, H.; Shibata, N.; Suzuki, K.; Takeuchi, S.

1980-01-01

Electron-irradiation studies on vapour-grown ZnO ribbon crystals have been carried out in situ in a high-voltage electron microscope. Dislocation loops nucleate both on stacking-fault planes and in the matrix by irradiation with electron accelerated through voltages higher than 700 kV at room temperature. Two types of loops with the Burgers vectors b=1/2c and b=a exist in the matrix, where a=1/3 and c=[0001]. On the other hand, loops with b=1/2c+a/3 and those with b=1/2c are formed on the prismatic fault planes and basal fault planes, respectively. Diffraction-contrast experiments show these loops to be of interstitial type. A re-irradiation experiment after the annealing indicates a possibility that there exist vacancies in the matrix at 700 0 C. (author)

Polyurethanes irradiation by accelerated electrons: molecular and supramolecular evolution, incidence on the extractable and biomedical implications; Irradiation de polyurethannes par electrons acceleres: evolution moleculaire et supramoleculaire, incidence sur les extractibles et implications biomedicales

Energy Technology Data Exchange (ETDEWEB)

Guignot, C

2002-11-15

Face to the development of radiosterilization and polymers medical devices it was wished to study the behavior of polyurethanes under accelerated electrons in oxidizing atmosphere. This study has been made to reveal the physico chemical and organisational modifications of polyurethanes for a medical use. (N.C.)

The electron accelerator in industry - safety aspects

International Nuclear Information System (INIS)

Kirthi, K.N.

1993-01-01

Electron beam accelerators are being used in increasing numbers in a variety of important applications. Commercial uses include radiography, food preservation, product sterilisation and radiation processing of materials. Since most of the industrial applications involve products, some that can be treated with electrons and others that require photons, electron accelerators serve this dual purpose economically. Although industrial accelerators are now regarded as standard products, finished installations show considerable diversity, reflecting the users, needs and planning. Because of the high radiation output, proper planning regarding safety is warranted. This paper discusses the hazards, safety and planning required during design and operation of the electron beam accelerators. (author). 4 refs., 1 fig

Obtaining alcohol from wooden waste of industry using an electron beam accelerator

International Nuclear Information System (INIS)

Naranjo, Rodrigo; Vallejo, Luz

2004-01-01

The present study refers to the application of a pre-treatment with electron beams to wooden powder to increase the cellulose conversion percentage in sugars during the acid hydrolysis processing and then getting alcohol by fermentation. The physical and chemical characterization of wooden powder was carried out, getting 66.39% cellulose, 3.1% wax and grease, 23.45% lignin, 6.18% pentosanes, 10.18% humidity, 0.89% ashes and the diameter of average particle equal to 11.56 mm. To irradiate wooden waste, an electron beam accelerator ELU 6U was used as a ionizing radiation source. It is installed in the Escuela Politecnica Nacional in Quito, Ecuador. Fermentation tests of hydrolyzed of irradiated wooden powder were done to determine the production of ethylic alcohol. The efficiency was 160 liters of ethanol to 100% from one ton of wooden waste, 66,4% cellulose. (The author)

Electron irradiation of power transistors

International Nuclear Information System (INIS)

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

1982-01-01

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

Study and realization of an electron linear accelerator. Dynamics of accelerated electrons

International Nuclear Information System (INIS)

Bernard, J.

1966-12-01

The theoretical characteristics of the electron linear accelerator are: 30 MeV for the energy W S and 250 mA for the peak current I c . The main utilization is the intense production of fast neutrons by the reactions (γ,n) and (γ,f) induced in a target of natural uranium by the accelerated electrons. In the first part of the thesis, relative to the study and the realization of the accelerator, a new equation of dispersion is established analytically when the guide is loaded with round-edged irises. The relation is compared with the equation established by CHU and Hansen, WALKINSHAW, KVASIL in the case of a guide loaded with flat-edged irises. The experimental and theoretical curves of dispersion are compared. The accuracy of every relation of dispersion is estimated. The second part of the thesis is relative to the theoretical study of the electrons dynamics in the guide; it allows the derivation of the parameters of the beam: dispersion of phase, energy, dispersion of energy and the relation W S = f (I c ). The results relative to the first experiments are given and compared with the theoretical expectations. (author) [fr

Low voltage electron beam accelerators

International Nuclear Information System (INIS)

Ochi, Masafumi

2003-01-01

Widely used electron accelerators in industries are the electron beams with acceleration voltage at 300 kV or less. The typical examples are shown on manufactures in Japan, equipment configuration, operation, determination of process parameters, and basic maintenance requirement of the electron beam processors. New electron beam processors with acceleration voltage around 100 kV were introduced maintaining the relatively high dose speed capability of around 10,000 kGy x mpm at production by ESI (Energy Science Inc. USA, Iwasaki Electric Group). The application field like printing and coating for packaging requires treating thickness of 30 micron or less. It does not require high voltage over 110 kV. Also recently developed is a miniature bulb type electron beam tube with energy less than 60 kV. The new application area for this new electron beam tube is being searched. The drive force of this technology to spread in the industries would be further development of new application, process and market as well as the price reduction of the equipment, upon which further acknowledgement and acceptance of the technology to societies and industries would entirely depend. (Y. Tanaka)

Low voltage electron beam accelerators

Energy Technology Data Exchange (ETDEWEB)

Ochi, Masafumi [Iwasaki Electric Co., Ltd., Tokyo (Japan)

2003-02-01

Widely used electron accelerators in industries are the electron beams with acceleration voltage at 300 kV or less. The typical examples are shown on manufactures in Japan, equipment configuration, operation, determination of process parameters, and basic maintenance requirement of the electron beam processors. New electron beam processors with acceleration voltage around 100 kV were introduced maintaining the relatively high dose speed capability of around 10,000 kGy x mpm at production by ESI (Energy Science Inc. USA, Iwasaki Electric Group). The application field like printing and coating for packaging requires treating thickness of 30 micron or less. It does not require high voltage over 110 kV. Also recently developed is a miniature bulb type electron beam tube with energy less than 60 kV. The new application area for this new electron beam tube is being searched. The drive force of this technology to spread in the industries would be further development of new application, process and market as well as the price reduction of the equipment, upon which further acknowledgement and acceptance of the technology to societies and industries would entirely depend. (Y. Tanaka)

Physics design of heavy-ion irradiation beam line on HI-13 tandem accelerator

International Nuclear Information System (INIS)

Zhu Fei; Peng Zhaohua; Hu Yueming; Jiao Xuesheng; Chen Dongfeng; Cao Yali

2014-01-01

Background: Heavy-ion microporous membrane is a new kind of filter material, which has prosperous application in the fields of medical and biological agents, electronic, food, environmental science, materials science, etc. Purpose: Polyester membranes were irradiated with 32 S produced by HI-13 tandem accelerator to develop a microporous membrane at CIAE, and the irradiation uniformity is determined by the beam distribution, also the microporous uniformity is required higher than 90%. Methods: An octupole magnet was used to correct the beam distribution from Gauss to uniform. Meanwhile, main parameters of beam line were given, and the alignment tolerances for optical elements were also analyzed. Results: Alignment tolerance of the optical elements could cause great influence on the beam center deviation in the process of correction, which would destroy the irradiation uniformity. Steering magnet was applied to meet with the design requirements. Conclusion: This study provides a practical and feasible way for industrial production of heavy-ion microporous membrane. (authors)

Degradation of carrageenan by low energy electron accelerator

International Nuclear Information System (INIS)

Relleve, L.; Aranilla, C.; Abad, L.; Dela Rosa, A.; Nagasawa, Naotsugu; Yagi, Toshiaki; Kume, Tamikazu; Yoshii, Fumio

2004-01-01

Degradation of κ-carrageenan using vessel-type low energy electron accelerator was investigated. Carrageenan with different molecular weights were obtained from irradiation of high molecular weight (HMW) and low molecular weight (LMW) κ-carrageenan. Other results presented were obtained from degradation studies of carrageenan by gamma rays. The decrease in molecular weight was accompanied by partial desulfation. From comparison of radiation degradation yield (Gd), it was found that the susceptibility to radiation of the three types of carrageenans in aqueous/gel forms follows the order of λ->ι->>κ- and could have been influenced by their conformational state. κ-carrageenan with molecular weight of ca. 10,000 showed strong growth promotion effect for potato in tissue culture. (author)

DARMSTADT: Superconducting electron accelerator in operation

International Nuclear Information System (INIS)

Anon.

1991-01-01

In December, the S-DALINAC superconducting radiofrequency electron accelerator at the Nuclear Physics Institute of Darmstadt's Technische Hochschule was completed. This pioneer continuous-wave (c.w.) machine passed a major milestone several years ago when it accelerated its first low energy electron beam

Investigation of instability of M23C6 particles in F82H steel under electron and ion irradiation conditions

Science.gov (United States)

Kano, Sho; Yang, Huilong; Shen, Jingjie; Zhao, Zishou; McGrady, John; Hamaguchi, Dai; Ando, Mamami; Tanigawa, Hiroyasu; Abe, Hiroaki

2018-04-01

In order to clarify the instability of M23C6 in F82H steel under irradiation, both electron irradiation using a high voltage electron microscope (HVEM) and ion irradiation using an ion accelerator were performed. For the electron irradiation, in-situ observation under 2 MV electron irradiation and ex-situ high resolution electron microscopic (HREM) analysis were utilized to evaluate the response of M23C6 against irradiation. The temperature dependence of the irradiation induced instability of the carbide was first confirmed: 293 K indicating severe loss of crystallinity due to dissolution of the constituent atoms though irradiation-enhanced diffusion under the vacancy diffusion by the focused electron beam irradiation. For the ion irradiation, 10.5 MeV-Fe3+ ion was applied to bombard the F82H steel at 673 K to achieve the displacement damage of ≈20 dpa at the depth of 1.0 μm from surface. Cross-section TEM specimens were prepared by a focused ion beam technique. The shrinkage of carbide particles was observed especially near the irradiation surface. Besides, the lattice fringes at the periphery of carbide were observed in the irradiated M23C6 by the HREM analysis, which is different from that observed in the electron irradiation. It was clarified that the instability of M23C6 is dependent on the irradiation conditions, indicating that the flow rate of vacancy type defects might be the key factor to cause the dissolution of constituent atoms of carbide particles into matrix under irradiation.

Electron irradiation of zeolites

International Nuclear Information System (INIS)

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

1999-01-01

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

Irradiation system for neutron capture therapy using the small accelerator

International Nuclear Information System (INIS)

Kobayashi, Tooru; Hoshi, Masaharu

2002-01-01

Neutron capture therapy (NCT) is to kill tumor cells that previously incorporated the stable isotope which generates heavy charged particles with a short range and a high linear energy transfer (LET) on neutron irradiation. Boron-10 is ordinarily used as such an isotope. The tumor tissue is neutron-irradiated at craniotomy after preceding craniotomy for tumor extraction: therefore two surgeries are required for the present NCT in Japan. The reactions 10 B(n, αγ) 7 Li and 7 Li (p, n) 7 Be are thought preferential for patients and doctors if a convenient small accelerator, not the reactor used at present, is available in the hospital because only one craniotomy is sufficient. Authors' examinations of the system for NCT using the small accelerator involve irradiation conditions, desirable energy spectrum of neutron, characterization of thermal and epi-thermal neutrons, social, practical and technical comparison of the reactor and accelerator, and usefulness of the reaction 7 Li (p, n) 7 Be. The system devoted to the NCT is awaited in future. (K.H.)

Probing electron acceleration and x-ray emission in laser-plasma accelerators

International Nuclear Information System (INIS)

Thaury, C.; Ta Phuoc, K.; Corde, S.; Brijesh, P.; Lambert, G.; Malka, V.; Mangles, S. P. D.; Bloom, M. S.; Kneip, S.

2013-01-01

While laser-plasma accelerators have demonstrated a strong potential in the acceleration of electrons up to giga-electronvolt energies, few experimental tools for studying the acceleration physics have been developed. In this paper, we demonstrate a method for probing the acceleration process. A second laser beam, propagating perpendicular to the main beam, is focused on the gas jet few nanosecond before the main beam creates the accelerating plasma wave. This second beam is intense enough to ionize the gas and form a density depletion, which will locally inhibit the acceleration. The position of the density depletion is scanned along the interaction length to probe the electron injection and acceleration, and the betatron X-ray emission. To illustrate the potential of the method, the variation of the injection position with the plasma density is studied

Inverse free-electron laser accelerator development

International Nuclear Information System (INIS)

Fisher, A.; Gallardo, J.; Steenbergen, A. van; Sandweiss, J.; Fang, J.M.

1994-06-01

The study of the Inverse Free-Electron Laser, as a potential mode of electron acceleration, has been pursued at Brookhaven National Laboratory for a number of years. More recent studies focused on the development of a low energy (few GeV), high gradient, multistage linear accelerator. The authors are presently designing a short accelerator module which will make use of the 50 MeV linac beam and high power (2 x 10 11 W) CO 2 laser beam of the Accelerator Test Facility (ATF) at the Center for Accelerator Physics (CAP), Brookhaven National Laboratory. These elements will be used in conjunction with a fast excitation (300 μsec pulse duration) variable period wiggler, to carry out an accelerator demonstration stage experiment

Container for gaseous samples for irradiation at accelerators

International Nuclear Information System (INIS)

Kupsch, H.; Riemenschneider, J.; Leonhardt, J.

1985-01-01

The invention concerns a container for gaseous samples for the irradiation at accelerators especially to generate short-lived radioisotopes. The container is also suitable for storage and transport of the target gas and can be multiply reused

The influence of accelerated electrons and γ-quanta (60Co) on activity of oxidative and hydrolytic enzymes of rat brain

International Nuclear Information System (INIS)

Lyshov, V.F.; Vasin, M.V.; Chernov, Yu.N.

1992-01-01

In experiments with 112 male Wistar rats it was shown that accelerated electrons (85 Gy) caused a significant increase in activities of by 15.8 % and (LDG) by 17.0 %, and a decrease in activities of AP and MAO by 10.6 and 7.8 % respectively within the sensorimotor region of the cerebral cortex immediately after irradiation. Activity of SDG and MAO decreased (by 16.4 % and 7.8 % respectively) in the caudate nucleus over the same period of time. An increase in the accelerated electron dose from 85 to 500 Gy did not change the direction and the rate of the radiation response of the enzymes. Exposure of rats to 60 Co-γ-quanta (75 Gy) increased SDG and LDG activity (by 21.4 and 17.3 % respectively) within the sensorimotor cortex as late as 10 min after irradiation. A repeated significant increase in SDG and LDG activity was observed 2 hr after irradiation

Effect of electron beam irradiation on thermal and mechanical properties of aluminum based epoxy composites

Science.gov (United States)

Visakh, P. M.; Nazarenko, O. B.; Sarath Chandran, C.; Melnikova, T. V.; Nazarenko, S. Yu.; Kim, J.-C.

2017-07-01

The epoxy resins are widely used in nuclear and aerospace industries. The certain properties of epoxy resins as well as the resistance to radiation can be improved by the incorporation of different fillers. This study examines the effect of electron beam irradiation on the thermal and mechanical properties of the epoxy composites filled with aluminum nanoparticles at percentage of 0.35 wt%. The epoxy composites were exposed to the irradiation doses of 30, 100 and 300 kGy using electron beam generated by the linear electron accelerator ELU-4. The effects of the doses on thermal and mechanical properties of the aluminum based epoxy composites were investigated by the methods of thermal gravimetric analysis, tensile test, and dynamic mechanical analysis. The results revealed that the studied epoxy composites showed good radiation resistance. The thermal and mechanical properties of the aluminum based epoxy composites increased with increasing the irradiation dose up to 100 kGy and decreased with further increasing the dose.

The IBA Rhodotron: an industrial high-voltage high-powered electron beam accelerator for polymers radiation processing

Science.gov (United States)

Van Lancker, Marc; Herer, Arnold; Cleland, Marshall R.; Jongen, Yves; Abs, Michel

1999-05-01

The Rhodotron is a high-voltage, high-power electron beam accelerator based on a design concept first proposed in 1989 by J. Pottier of the French Atomic Agency, Commissariat à l'Energie Atomique (CEA). In December 1991, the Belgian particle accelerator manufacturer, Ion Beam Applications s.a. (IBA) entered into an exclusive agreement with the CEA to develop and industrialize the Rhodotron. Electron beams have long been used as the preferential method to cross-link a variety of polymers, either in their bulk state or in their final form. Used extensively in the wire and cable industry to toughen insulating jackets, electron beam-treated plastics can demonstrate improved tensile and impact strength, greater abrasion resistance, increased temperature resistance and dramatically improved fire retardation. Electron beams are used to selectively cross-link or degrade a wide range of polymers in resin pellets form. Electron beams are also used for rapid curing of advanced composites, for cross-linking of floor-heating and sanitary pipes and for cross-linking of formed plastic parts. Other applications include: in-house and contract medical device sterilization, food irradiation in both electron and X-ray modes, pulp processing, electron beam doping of semi-conductors, gemstone coloration and general irradiation research. IBA currently markets three models of the Rhodotron, all capable of 10 MeV and alternate beam energies from 3 MeV upwards. The Rhodotron models TT100, TT200 and TT300 are typically specified with guaranteed beam powers of 35, 80 and 150 kW, respectively. Founded in 1986, IBA, a spin-off of the Cyclotron Research Center at the University of Louvain (UCL) in Belgium, is a pioneer in accelerator design for industrial-scale production.

The IBA Rhodotron: an industrial high-voltage high-powered electron beam accelerator for polymers radiation processing

International Nuclear Information System (INIS)

Lancker, Marc van; Herer, Arnold; Cleland, Marshall R.; Jongen, Yves; Abs, Michel

1999-01-01

The Rhodotron is a high-voltage, high-power electron beam accelerator based on a design concept first proposed in 1989 by J. Pottier of the French Atomic Agency, Commissariat a l'Energie Atomique (CEA). In December 1991, the Belgian particle accelerator manufacturer, Ion Beam Applications s.a. (IBA) entered into an exclusive agreement with the CEA to develop and industrialize the Rhodotron. Electron beams have long been used as the preferential method to cross-link a variety of polymers, either in their bulk state or in their final form. Used extensively in the wire and cable industry to toughen insulating jackets, electron beam-treated plastics can demonstrate improved tensile and impact strength, greater abrasion resistance, increased temperature resistance and dramatically improved fire retardation. Electron beams are used to selectively cross-link or degrade a wide range of polymers in resin pellets form. Electron beams are also used for rapid curing of advanced composites, for cross-linking of floor-heating and sanitary pipes and for cross-linking of formed plastic parts. Other applications include: in-house and contract medical device sterilization, food irradiation in both electron and X-ray modes, pulp processing, electron beam doping of semi-conductors, gemstone coloration and general irradiation research. IBA currently markets three models of the Rhodotron, all capable of 10 MeV and alternate beam energies from 3 MeV upwards. The Rhodotron models TT100, TT200 and TT300 are typically specified with guaranteed beam powers of 35, 80 and 150 kW, respectively. Founded in 1986, IBA, a spin-off of the Cyclotron Research Center at the University of Louvain (UCL) in Belgium, is a pioneer in accelerator design for industrial-scale production

Electron acceleration in the bubble regime

Energy Technology Data Exchange (ETDEWEB)

Jansen, Oliver

2014-02-03

The bubble regime of laser-wakefield acceleration has been studied over the recent years as an important alternative to classical accelerators. Several models and theories have been published, in particular a theory which provides scaling laws for acceleration parameters such as energy gain and acceleration length. This thesis deals with numerical simulations within the bubble regime, their comparison to these scaling laws and data obtained from experiments, as well as some specific phenomenona. With a comparison of the scaling laws with numerical results a parameter scan was able to show a large parameter space in which simulation and theory agree. An investigation of the limits of this parameter space revealed boundaries to other regimes, especially at very high (a{sub 0} > 100) and very low laser amplitudes (a{sub 0} < 4). Comparing simulation data with data from experiments concerning laser pulse development and electron energies, it was found that experimental results can be adequately reproduced using the Virtual-Laser-Plasma-Laboratory code. In collaboration with the Institut fuer Optik und Quantenelektronik at the Friedrich-Schiller University Jena synchrotron radiation emitted from the inside of the bubble was investigated. A simulation of the movement of the electrons inside the bubble together with time dependent histograms of the emitted radiation helped to prove that the majority of radiation created during a bubble acceleration originates from the inside of the bubble. This radiation can be used to diagnose the amplitude of oscillation of the trapped electrons. During a further study it was proven that the polarisation of synchrotron radiation from a bubble contains information about the exact oscillation direction. This oscillation was successfully controlled by using either a laser pulse with a tilted pulse front or an asymmetric laser pulse. First results of ongoing studies concerning injecting electrons into an existing bubble and a scheme called

Dosimetric comparison of proton and photon three-dimensional, conformal, external beam accelerated partial breast irradiation techniques

International Nuclear Information System (INIS)

Kozak, Kevin R.; Katz, Angela; Adams, Judith C.; Crowley, Elizabeth M.; Nyamwanda, Jacqueline A.C.; Feng, Jennifer K.C.; Doppke, Karen P.; DeLaney, Thomas F.; Taghian, Alphonse G.

2006-01-01

Purpose: To compare the dosimetry of proton and photon-electron three-dimensional, conformal, external beam accelerated partial breast irradiation (3D-CPBI). Methods and Materials: Twenty-four patients with fully excised, Stage I breast cancer treated with adjuvant proton 3D-CPBI had treatment plans generated using the mixed-modality, photon-electron 3D-CPBI technique. To facilitate dosimetric comparisons, planning target volumes (PTVs; lumpectomy site plus 1.5-2.0 cm margin) and prescribed dose (32 Gy) were held constant. Plans were optimized for PTV coverage and normal tissue sparing. Results: Proton and mixed-modality plans both provided acceptable PTV coverage with 95% of the PTV receiving 90% of the prescribed dose in all cases. Both techniques also provided excellent dose homogeneity with a dose maximum exceeding 110% of the prescribed dose in only one case. Proton 3D-CPBI reduced the volume of nontarget breast tissue receiving 50% of the prescribed dose by an average of 36%. Statistically significant reductions in the volume of total ipsilateral breast receiving 100%, 75%, 50%, and 25% of the prescribed dose were also observed. The use of protons resulted in small, but statistically significant, reductions in the radiation dose delivered to 5%, 10%, and 20% of ipsilateral and contralateral lung and heart. The nontarget breast tissue dosimetric advantages of proton 3D-CPBI were not dependent on tumor location, breast size, PTV size, or the ratio of PTV to breast volume. Conclusions: Compared to photon-electron 3D-CPBI, proton 3D-CPBI significantly reduces the volume of irradiated nontarget breast tissue. Both approaches to accelerated partial breast irradiation offer exceptional lung and heart sparing

Dynamics of electron acceleration in laser-driven wakefields. Acceleration limits and asymmetric plasma waves

Energy Technology Data Exchange (ETDEWEB)

Popp, Antonia

2011-12-16

The experiments presented in this thesis study several aspects of electron acceleration in a laser-driven plasma wave. High-intensity lasers can efficiently drive a plasma wave that sustains electric fields on the order of 100 GV/m. Electrons that are trapped in this plasma wave can be accelerated to GeV-scale energies. As the accelerating fields in this scheme are 3-4 orders of magnitude higher than in conventional radio-frequency accelerators, the necessary acceleration distance can be reduced by the same factor, turning laser-wakefield acceleration (LWFA) into a promising compact, and potentially cheaper, alternative. However, laser-accelerated electron bunches have not yet reached the parameter standards of conventional accelerators. This work will help to gain better insight into the acceleration process and to optimize the electron bunch properties. The 25 fs, 1.8 J-pulses of the ATLAS laser at the Max-Planck-Institute of Quantum Optics were focused into a steady-state flow gas cell. This very reproducible and turbulence-free gas target allows for stable acceleration of electron bunches. Thus the sensitivity of electron parameters to subtle changes of the experimental setup could be determined with meaningful statistics. At optimized experimental parameters, electron bunches of {approx}50 pC total charge were accelerated to energies up to 450 MeV with a divergence of {approx}2 mrad FWHM. As, in a new design of the gas cell, its length can be varied from 2 to 14 mm, the electron bunch energy could be evaluated after different acceleration distances, at two different electron densities. From this evolution important acceleration parameters could be extracted. At an electron density of 6.43. 10{sup 18} cm{sup -3} the maximum electric field strength in the plasma wave was determined to be {approx}160 GV/m. The length after which the relativistic electrons outrun the accelerating phase of the electric field and are decelerated again, the so-called dephasing length

Dynamics of electron acceleration in laser-driven wakefields. Acceleration limits and asymmetric plasma waves

International Nuclear Information System (INIS)

Popp, Antonia

2011-01-01

The experiments presented in this thesis study several aspects of electron acceleration in a laser-driven plasma wave. High-intensity lasers can efficiently drive a plasma wave that sustains electric fields on the order of 100 GV/m. Electrons that are trapped in this plasma wave can be accelerated to GeV-scale energies. As the accelerating fields in this scheme are 3-4 orders of magnitude higher than in conventional radio-frequency accelerators, the necessary acceleration distance can be reduced by the same factor, turning laser-wakefield acceleration (LWFA) into a promising compact, and potentially cheaper, alternative. However, laser-accelerated electron bunches have not yet reached the parameter standards of conventional accelerators. This work will help to gain better insight into the acceleration process and to optimize the electron bunch properties. The 25 fs, 1.8 J-pulses of the ATLAS laser at the Max-Planck-Institute of Quantum Optics were focused into a steady-state flow gas cell. This very reproducible and turbulence-free gas target allows for stable acceleration of electron bunches. Thus the sensitivity of electron parameters to subtle changes of the experimental setup could be determined with meaningful statistics. At optimized experimental parameters, electron bunches of ∼50 pC total charge were accelerated to energies up to 450 MeV with a divergence of ∼2 mrad FWHM. As, in a new design of the gas cell, its length can be varied from 2 to 14 mm, the electron bunch energy could be evaluated after different acceleration distances, at two different electron densities. From this evolution important acceleration parameters could be extracted. At an electron density of 6.43. 10 18 cm -3 the maximum electric field strength in the plasma wave was determined to be ∼160 GV/m. The length after which the relativistic electrons outrun the accelerating phase of the electric field and are decelerated again, the so-called dephasing length, was found to be 4.9 mm

Electron beam irradiating device

Energy Technology Data Exchange (ETDEWEB)

Shinohara, K

1969-12-20

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

Relativistic acceleration and retardation effects on photoemission of intense electron short pulses, in RF-FEL photoinjectors

International Nuclear Information System (INIS)

Dolique, J.M.; Coacolo, M.

1991-01-01

In high-power free electron lasers, self-field effects in the electron beam are often the most important phenomenon on which the beam quality depends. These effects are generally conceived as space-charge effects, and described by a Poisson equation in a beam frame. In RF-FEL photoinjectors, the electrons of the intense short pulse produced by laser irradiation are submitted, just after their photoemission, to such a strong acceleration that relativistic acceleration and retardation effects are discussed, from the rigorous calculation of the Lienard-Wiechert velocity- and acceleration electric and magnetic fields, as a function of RF-electric field and beam parameters. The beam pulse is assumed to be axisymmetric, with a constant photoemitted current density. Consequences for the maximum current density that can be extracted are considered (the 'self-field limit,' a name more appropriate than 'space-charge limit' for the present conditions where electro-dynamic phenomena play an important role)

Laser vacuum acceleration of a relativistic electron bunch

Energy Technology Data Exchange (ETDEWEB)

Glazyrin, I V; Karpeev, A V; Kotova, O G; Nazarov, K S [E.I. Zababakhin All-Russian Scientific-Research Institute of Technical Physics, Russian Federal Nuclear Centre, Snezhinsk, Chelyabinsk region (Russian Federation); Bychenkov, V Yu [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2015-06-30

With regard to the problem of laser acceleration of a relativistic electron bunch we present a scheme of its vacuum acceleration directly by a relativistic intensity laser pulse. The energy of the electron bunch injected into the laser pulse leading edge increases during its coaxial movement to a thin, pulse-reflecting target. The laser-accelerated electrons continue to move free forward, passing through the target. The study of this acceleration scheme in the three-dimensional geometry is verified in a numerical simulation by the particle-in-cell method, which showed that the energy of a part of the electrons can increase significantly compared to the initial one. Restrictions are discussed, which impose limiting values of energy and total charge of accelerated electrons. (superstrong light fields)

Characterization of Irradiated and Non-Irradiated Rubber from Automotive Scrap Tires

Science.gov (United States)

Souza, Clécia Moura; Silva, Leonardo G.

The aim of this work was to characterize the samples of irradiated and non-irradiated rubber from automotive scrap tires. Rubber samples from scrap tires were irradiated at irradiation doses of 200, 400 and 600kGy in an electron beam accelerator. Subsequently, both the irradiated and non-irradiated samples were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), tensile strength mechanical test, and Fourier transform infrared (FTIR) spectrophotometry.

Electron pulse shaping in the FELIX RF accelerator

International Nuclear Information System (INIS)

Weits, H.H.; Geer, C.A.J. van der; Oepts, D.; Meer, A.F.G. van der

1999-01-01

The FELIX free-electron laser uses short pulses of relativistic electrons produced by an RF accelerator. The design target for the duration of these electron bunches was around 3 ps. In experiments we observed that the bunches emit coherently enhanced spontaneous emission (CSE) when they travel through an undulator. It was demonstrated that the power level of the CSE critically depends on the settings of the accelerator. In this article we seek to explain these observations by studying the length and shape of the electron bunches as a function of the settings of the accelerator. A particle-tracking model was used to simulate the acceleration and transport processes. These include bunch compression in a 14-cell travelling wave buncher cavity, acceleration in a travelling wave linear accelerator, and passage through a (dispersive) chicane structure. The effect of the phase setting of the RF accelerating field with respect to the arrival time of the electron bunch in each accelerator structure was studied. The parameter range of the simulations is related to that of an actual free-electron laser experiment using these bunches. We find that, for specific settings of the accelerating system, electron pulses with a length of 350 μm FWHM (1 ps) are produced. The charge in the bunch rises steeply within a distance of 25 μm. This bunch shape explains the high level of coherently enhanced spontaneous emission observed in the FELIX laser. (author)

Evaluation of induced radioactivity in 10 MeV-Electron irradiated spices, (2); [beta]-ray counting

Energy Technology Data Exchange (ETDEWEB)

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

1994-02-01

In order to check radioactivity of beta-emmitters produced by ([gamma], n) reactions which could occur at energies up to 10 MeV, black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy. Beta-rays were counted using a 2[pi] gas flow counter and a liquid scintillation counter. Any induced radioactivity could not be detected in irradiated samples. When inorganic compounds containing the nuclides in the list were artificially added in the samples and were irradiated, the [beta]-activities were detected. From the amount of observed radioactivities of [beta]-emmitters produced in the compounds as photonuclear products, it is concluded that the induced radioactivity in natural samples by 10 MeV-electron irradiation were far smaller than natural radioactivity from [sup 40]K contained in the samples and, hence, its biological effects should be negligible. (author).

Ultra-High-Contrast Laser Acceleration of Relativistic Electrons in Solid Targets

Energy Technology Data Exchange (ETDEWEB)

Higginson, Drew Pitney [Univ. of California, San Diego, CA (United States)

2013-01-01

The cone-guided fast ignition approach to Inertial Con nement Fusion requires laser-accelerated relativistic electrons to deposit kilojoules of energy within an imploded fuel core to initiate fusion burn. One obstacle to coupling electron energy into the core is the ablation of material, known as preplasma, by laser energy proceeding nanoseconds prior to the main pulse. This causes the laser-absorption surface to be pushed back hundreds of microns from the initial target surface; thus increasing the distance that electrons must travel to reach the imploded core. Previous experiments have shown an order of magnitude decrease in coupling into surrogate targets when intentionally increasing the amount of preplasma. Additionally, for electrons to deposit energy within the core, they should have kinetic energies on the order of a few MeV, as less energetic electrons will be stopped prior to the core and more energetic electrons will pass through the core without depositing much energy. Thus a quantitative understanding of the electron energy spectrum and how it responds to varied laser parameters is paramount for fast ignition. For the rst time, this dissertation quantitatively investigates the acceleration of electrons using an ultra-high-contrast laser. Ultra-high-contrast lasers reduce the laser energy that reaches the target prior to the main pulse; drastically reducing the amount of preplasma. Experiments were performed in a cone-wire geometry relevant to fast ignition. These experiments irradiated the inner-tip of a Au cone with the laser and observed electrons that passed through a Cu wire attached to the outer-tip of the cone. The total emission of K x-rays is used as a diagnostic to infer the electron energy coupled into the wire. Imaging the x-ray emission allowed an e ective path-length of electrons within the wire to be determined, which constrained the electron energy spectrum. Experiments were carried out on the ultra-high-contrast Trident laser at Los

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

International Nuclear Information System (INIS)

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

2015-01-01

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

High Power Electron Accelerator Prototype

CERN Document Server

Tkachenko, Vadim; Cheskidov, Vladimir; Korobeynikov, G I; Kuznetsov, Gennady I; Lukin, A N; Makarov, Ivan; Ostreiko, Gennady; Panfilov, Alexander; Sidorov, Alexey; Tarnetsky, Vladimir V; Tiunov, Michael A

2005-01-01

In recent time the new powerful industrial electron accelerators appear on market. It caused the increased interest to radiation technologies using high energy X-rays due to their high penetration ability. However, because of low efficiency of X-ray conversion for electrons with energy below 5 MeV, the intensity of X-rays required for some industrial applications can be achieved only when the beam power exceeds 300 kW. The report describes a project of industrial electron accelerator ILU-12 for electron energy up to 5 MeV and beam power up to 300 kW specially designed for use in industrial applications. On the first stage of work we plan to use the existing generator designed for ILU-8 accelerator. It is realized on the GI-50A triode and provides the pulse power up to 1.5-2 MW and up to 20-30 kW of average power. In the report the basic concepts and a condition of the project for today are reflected.

Irradiation-Accelerated Corrosion of Reactor Core Materials. Final Report

Energy Technology Data Exchange (ETDEWEB)

Jiao, Zhujie [Univ. of Michigan, Ann Arbor, MI (United States); Was, Gary [Univ. of Michigan, Ann Arbor, MI (United States); Bartels, David [Univ. of Notre Dame, IN (United States)

2015-04-02

This project aims to understand how radiation accelerates corrosion of reactor core materials. The combination of high temperature, chemically aggressive coolants, a high radiation flux and mechanical stress poses a major challenge for the life extension of current light water reactors, as well as the success of most all GenIV concepts. Of these four drivers, the combination of radiation and corrosion places the most severe demands on materials, for which an understanding of the fundamental science is simply absent. Only a few experiments have been conducted to understand how corrosion occurs under irradiation, yet the limited data indicates that the effect is large; irradiation causes order of magnitude increases in corrosion rates. Without a firm understanding of the mechanisms by which radiation and corrosion interact in film formation, growth, breakdown and repair, the extension of the current LWR fleet beyond 60 years and the success of advanced nuclear energy systems are questionable. The proposed work will address the process of irradiation-accelerated corrosion that is important to all current and advanced reactor designs, but remains very poorly understood. An improved understanding of the role of irradiation in the corrosion process will provide the community with the tools to develop predictive models for in-reactor corrosion, and to address specific, important forms of corrosion such as irradiation assisted stress corrosion cracking.

Electron beam irradiation: novel technology for phytosanitary purposes

International Nuclear Information System (INIS)

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

2015-01-01

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

High power electron accelerators for flue gas treatment

International Nuclear Information System (INIS)

Zimek, Z.

2011-01-01

Flue gas treatment process based on electron beam application for SO 2 and NO x removal was successfully demonstrated in number of laboratories, pilot plants and industrial demonstration facilities. The industrial scale application of an electron beam process for flue gas treatment requires accelerators modules with a beam power 100-500 kW and electron energy range 0.8-1.5 MeV. The most important accelerator parameters for successful flue gas radiation technology implementation are related to accelerator reliability/availability, electrical efficiency and accelerator price. Experience gained in high power accelerators exploitation in flue gas treatment industrial demonstration facility was described and high power accelerator constructions have been reviewed. (author)

Orientation and properties of the blends on high-molecular mass polyacrylonitrile with trihydroxyethylenedimethacrylate under electron irradiation

International Nuclear Information System (INIS)

Lomonosova, N.V.

1998-01-01

Molecular orientation of the drawn blends of high- molecular-mass poly(acrylonitrile) containing 5-50 wt % of trihydroxyethylenedimethacrylate and a change in the orientation of the drawn samples upon irradiation with accelerated electrons was studied by methods of birefringence, isometric heating, and IR dichroism. The degree of orientation of the unirradiated blends containing certain amounts of oligomer exceed that of the individual polymer. In the region of large drawing ratios, the differential degree of orientation of the polymer matrix is not affected by the irradiation, while the orientation of the oligomer component increase. High values of the strength (600-730 MPa) and the modulus (18-22 GPa) of the compositions are due to the presence of a crystalline skeleton formed by unfolded chains of the polymer matrix stabilized by the electron irradiation induced cross-linking

Windowless Electron Beam Experimental Irradiation WEBExplr

International Nuclear Information System (INIS)

Heyse, J.

2009-01-01

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

The electronic logbook for LNL accelerators

International Nuclear Information System (INIS)

Canella, S.; Carletto, O.

2012-01-01

In spring 2009 all run-time data concerning the particle accelerators at LNL (Legnaro National Laboratory) were still registered mainly on paper. The electrostatic accelerator TANDEM-XTU and its Negative Source data were logged on a large format paper logbook. For the ALPI booster and the PIAVE injector with its Positive ECR Source a number of independent paper notebooks were used, together with plain data files containing raw instant snapshots of the RF super-conductive accelerators. At that time a decision was taken to build a new tool for a general electronic registration of accelerators run-time data. The result of this effort, the LNL electronic logbook, is here presented. The LNL electronic logbook is a many-layers software tool that is made of data sets and software programs. It is used to register states, events, texts, images and files according to the shift structures in the working time of the LNL accelerators. The same system is used to register data and to retrieve them. It may be accessed by standard browser on any platform

Strain acceleration of the low temperature irradiated zirconium

International Nuclear Information System (INIS)

Fortis, Ana M.; Coccoz, Guillermina D. H.

2003-01-01

The strain of a Zr-0,06 at.% 235 U specimen irradiated during 4800 h in the RA-3 at a temperature near 40 C degrees is presented. An equivalent neutron fluence of 3.1 x 10 26 n m -2 was achieved by means of the generation of fission fragment within the material. The experimental conditions are described and a sudden strain acceleration independent of the neutron flux variations occurred during irradiation is shown. This behavior is compared with previous data obtained at different temperatures. (author)

Dose controlled low energy electron irradiator for biomolecular films.

Science.gov (United States)

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

2016-03-01

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

Dose controlled low energy electron irradiator for biomolecular films

Energy Technology Data Exchange (ETDEWEB)

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

2016-03-15

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

Electron irradiation effect on single crystal of niobium

International Nuclear Information System (INIS)

Otero, M.P.; Lucki, G.

1984-01-01

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

Collective accelerator for electron colliders

Energy Technology Data Exchange (ETDEWEB)

Briggs, R.J.

1985-05-13

A recent concept for collective acceleration and focusing of a high energy electron bunch is discussed, in the context of its possible applicability to large linear colliders in the TeV range. The scheme can be considered to be a member of the general class of two-beam accelerators, where a high current, low voltage beam produces the acceleration fields for a trailing high energy bunch.

Collective accelerator for electron colliders

International Nuclear Information System (INIS)

Briggs, R.J.

1985-01-01

A recent concept for collective acceleration and focusing of a high energy electron bunch is discussed, in the context of its possible applicability to large linear colliders in the TeV range. The scheme can be considered to be a member of the general class of two-beam accelerators, where a high current, low voltage beam produces the acceleration fields for a trailing high energy bunch

ELECTRON ACCELERATION BY MULTI-ISLAND COALESCENCE

International Nuclear Information System (INIS)

Oka, M.; Phan, T.-D.; Krucker, S.; Fujimoto, M.; Shinohara, I.

2010-01-01

Energetic electrons of up to tens of MeV are created during explosive phenomena in the solar corona. While many theoretical models consider magnetic reconnection as a possible way of generating energetic electrons, the precise roles of magnetic reconnection during acceleration and heating of electrons still remain unclear. Here, we show from two-dimensional particle-in-cell simulations that coalescence of magnetic islands that naturally form as a consequence of tearing mode instability and associated magnetic reconnection leads to efficient energization of electrons. The key process is the secondary magnetic reconnection at the merging points, or the 'anti-reconnection', which is, in a sense, driven by the converging outflows from the initial magnetic reconnection regions. By following the trajectories of the most energetic electrons, we found a variety of different acceleration mechanisms but the energization at the anti-reconnection is found to be the most important process. We discuss possible applications to the energetic electrons observed in the solar flares. We anticipate our results to be a starting point for more sophisticated models of particle acceleration during the explosive energy release phenomena.

Electron accelerator for tunneling through hard rock

International Nuclear Information System (INIS)

Avery, R.T.; Keefe, D.

1975-10-01

Earlier work demonstrated that intense sub-microsecond bursts of energetic electrons cause significant pulverization and spalling of a variety of rock types. The spall debris generally consists of sand, dust, and small flakes. If carried out at rapid repetition rate, this can lead to a promising technique for increasing the speed and reducing the cost of underground excavation of tunnels, mines, and storage spaces. The conceptual design features of a Pulsed Electron Tunnel Excavator capable of tunneling approximately ten times faster than conventional drill/blast methods are presented, with primary emphasis on the electron accelerator and only a brief description of the tunneling aspects. Of several candidate types of accelerators, a linear induction accelerator producing electron pulses (5 MV, 5 kA, 1.0 μs = 25 kJ) at a 360 Hz rate was selected for the conceptual example. This provides the required average electron beam power output of 9 MW. The feasibility of such an accelerator is discussed

Electron accelerator for tunneling through hard rock

International Nuclear Information System (INIS)

Avery, R.T.; Keefe, D.

1975-01-01

Earlier work demonstrated that intense sub-microsecond bursts of energetic electrons cause significant pulverization and spalling of a variety of rock types. The spall debris generally consists of sand, dust, and small flakes. If carried out at rapid repetition rate, this can lead to a promising technique for increasing the speed and reducing the cost of underground excavation of tunnels, mines, and storage spaces. The conceptual design features of a Pulsed Electron Tunnel Excavator capable of tunneling approximately ten times faster than conventional drill/blast methods are presented with primary emphasis on the electron accelerator and only a brief description of the tunneling aspects. Of several candidate types of accelerators, a linear induction accelerator producing electron pulses (5 MV, 5 kA, 1.0 μs = 25 kJ) at a 360 Hz rate was selected for the conceptual example. This provides the required average electron beam power output of 9 MW. The feasibility of such an accelerator is discussed

Auroral electron acceleration by lower-hybrid waves

International Nuclear Information System (INIS)

Bingham, R.; Bryant, D.A.; Hall, D.S.

1986-01-01

Because the particles and electric fields association with inverted-V electron streams do not have the characteristics expected for acceleration by a quasistatic potential difference, the possiblity that the electrons are stochastically accelerated by waves is investigated. It is demonstrated that the lower hybrid waves seen on auroral field lines have the righ properties to account for the electron acceleration. It is further shown that the lower hybrid wave power measured on auroral field lines can be generated by the streaming ions observed at the boundary of the plasma sheet, and that this wave power is sufficient to account for the electron power observed close to the atmosphere. (author)

Effects of electron-beam irradiation to the hydroxyapatite and tricalcium phosphate mixtures for the development of new synthetic bone substitutes

Energy Technology Data Exchange (ETDEWEB)

Kim, Soung Min; Eo, Mi Young; Kang, Ji Young; Park, Jung Min; Seo, Mi Hyun; Myoung, Hoon; Lee, Jong Ho [Seoul National Univ., Seoul (Korea, Republic of); Han, Young Hwan; Lee, Byung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2010-07-01

The aim of this study is to evaluate the effect and potential of electron beam irradiation treatment to new bone formation and healing in rat calvarial bone defects using hydroxyapatite and tricalcium phosphate mixtures. We used 1.0-2.0 MeV linear accelerator and 2.0 MeV superconductive linear accelerator with different irradiation dose such as 1, 30, 60 kGy. Structural changes in this synthetic bone material were analyzed in vitro, such as SEM, elementary and FE-SEM, ATR-IR, and CSR. And after sterilization with ethylene oxide, we use it as a bone graft material, in vivo. Bilateral, standardized truenesses circular calvarial defects, 7.0 mm in diameter, were created in male Sprague-Dawley rats. In each experimental group, the defect was filled with electron beam irradiated synthetic bony mixtures. Rate were sacrificed 2, 4 and 8 weeks post-op. for radiographic, histomorphologic, immunohistochemical staining, TEM, and elementary analysis.

High power electron accelerators for flue gas treatment

Energy Technology Data Exchange (ETDEWEB)

Zimek, Z. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

2011-07-01

Flue gas treatment process based on electron beam application for SO{sub 2} and NO{sub x} removal was successfully demonstrated in number of laboratories, pilot plants and industrial demonstration facilities. The industrial scale application of an electron beam process for flue gas treatment requires accelerators modules with a beam power 100-500 kW and electron energy range 0.8-1.5 MeV. The most important accelerator parameters for successful flue gas radiation technology implementation are related to accelerator reliability/availability, electrical efficiency and accelerator price. Experience gained in high power accelerators exploitation in flue gas treatment industrial demonstration facility was described and high power accelerator constructions have been reviewed. (author)

Effect of accelerated electron beam on pesticides removal of effluents from flower plantations

International Nuclear Information System (INIS)

Ramirez, T.; Armas, M.; Uzcategui, M.

2006-01-01

Flower industry in Ecuador uses a great quantity of pesticides for flowers growing; many of them are toxic and no biodegradable, which contaminate the different effluents. The study of this research is focused to the possibility of using electron beam radiation generated by electron accelerator in order to decrease the concentration of pesticides in effluents both from flower cultivation and from treatment of flowers. The research is initiated with a survey to twelve flower plantations located in the provinces of Pichincha and Cotopaxi (Ecuador), with the purpose of knowing the class of used pesticides, its form of utilization before, during and after fumigation process, the class of staff working in flower industry and the methods of effluents treatment that are using. The information on importation of pesticides and exportation of different classes of flowers was carried out, as well as the flowers sales, with the purpose of selecting the pesticides to be studied. The study of electron beam influence was realized with 6 pesticides considered toxic (Diazinon, procloraz, imidacloprid, dimetoato, carbofuran and metiocarb).The studied variables were: irradiation dose, pesticide concentration, irradiation atmosphere and pH effect. Besides, pH changes, formation of nitrites, nitrates, sulphates, sulfides, ammonium ion and cyanides, after irradiation process of pesticides in aqueous solutions were analyzed. In general, the obtained degradation of pesticides was 99 % for pesticides: procloraz, imidacloprid, carbofuran and dimetoato, and 67% for metiocarb pesticide, when the pesticide concentration was 50 ppm and 5 kGy irradiation dose. (The author)

Neutron fluence in a 18 MeV Electron Accelerator for Therapy

International Nuclear Information System (INIS)

Paredes G, L.C.

2001-01-01

An investigation was made on the theoretical fundamentals for the determination of the neutron fluence in a linear electron accelerator for radiotherapy applications and the limit values of leakage neutron radiation established by guidelines and standards in radiation protection for these type of accelerators. This investigation includes the following parts: a) Exhaustive bibliographical review on the topics mentioned above, in order to combine and to update the necessary basic information to facilitate the understanding of this subject; b) Analysis of the accelerator operation and identification of its main components, specially in the accelerator head; c) Study of different types of targets and its materials for the Bremsstrahlung production which is based on the electron initial energy, the thickness of the target, and its angular distribution and energy, which influences in the neutron generation by means of the photonuclear and electro disintegration reactions; d) Analysis of the neutron yield based on the target type and its thickness, the energy of electrons and photons; e) Analysis of the neutron energy spectra generated in the accelerator head, inside and outside the treatment room; f) Study of the dosimetry fundamentals for neutron and photon mixed fields, the dosimeter selection criteria and standards applied for these applications, specially the Panasonic U D-809 thermoluminescent dosemeter and C R-39 nuclear track dosimeter; g) Theoretical calculation of the neutron yield using a simplified geometric model for the accelerator head with spherical cell, which considers the target, primary collimator, flattener filter, movable collimators and the head shielding as the main components for radiation production. The cases with W and Pb shielding for closed movable collimators and an irradiation field of 20 x 20 cm 2 were analyzed and, h) Experimental evaluation of the leakage neutron radiation from the patient and head planes, observing that the accelerator

Proceedings of the FNCA 2003 workshop on application of electron accelerator. Radiation system for thin film

International Nuclear Information System (INIS)

Yoshii, Fumio; Kume, Tamikazu

2004-06-01

'Forum for Nuclear Cooperation in Asia (FNCA) Workshop on Application of Electron Accelerator' was sponsored by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) and co-hosted by Malaysian Institute for Nuclear Technology Research (MINT) and Japan Atomic Energy Research Institute (JAERI). It was held at the Legend Hotel, Kuala Lumpur, Malaysia from 18 to 22 August 2003. The Workshop was attended by 28 experts on application of electron accelerator from each of the participating countries, i.e., China, Indonesia, Korea, Malaysia, The Philippines, Thailand and Vietnam, and 5 participants from Japan. On the first day, a National Executive Management Seminar on Application of Electron Accelerator was held and attended by 87 participants. Total of 19 papers including Seminar lectures, invited papers on film treatment by electron beam, and country reports on EB irradiation system were presented. The major areas of interest of FNCA member states for cooperation were identified for application of low energy electron accelerator as liquid, thin film and granules. The flue gas and wastewater treatments were added to the above major areas. Based on the proposal from the participating countries, discussions were carried out to re-formulate the work plan of the project for three years until FY 2004. All manuscripts submitted by every speaker were included in the proceedings. The 19 of the presented papers are indexed individually. (J.P.N.)

Air-electron stream interactions during magnetic resonance IGRT. Skin irradiation outside the treatment field during accelerated partial breast irradiation

Energy Technology Data Exchange (ETDEWEB)

Park, Jong Min [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Advanced Institutes of Convergence Technology, Robotics Research Laboratory for Extreme Environments, Suwon (Korea, Republic of); Shin, Kyung Hwan; Wu, Hong-Gyun [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of); Kim, Jung-in; Park, So-Yeon; Kim, Jin Ho [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Jeon, Seung Hyuck [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Choi, Noorie [Seoul National University College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of)

2018-01-15

To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm{sup 2}, respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field. (orig.) [German] Beim Einsatz eines Magnetresonanztomographie(MRT)-gefuehrten Bestrahlungsgeraets kann durch die Wechselwirkung von Magnetfeld und Strahlenquelle unerwuenscht

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

International Nuclear Information System (INIS)

Kijima, Toshiyuki; Nakase, Yoshiaki

1993-01-01

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

A 20 keV electron gun system for the electron irradiation experiments

International Nuclear Information System (INIS)

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

2005-01-01

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

A 20 keV electron gun system for the electron irradiation experiments

Energy Technology Data Exchange (ETDEWEB)

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

2005-01-01

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

Green coffee decontamination by electron beam irradiation

International Nuclear Information System (INIS)

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

2005-01-01

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

Technology and application of two sets of industrial electron accelerators

International Nuclear Information System (INIS)

Hua Degen

2000-01-01

The radiation industry in China Academy of Engineering Physics (CAEP) has had a big scale, and the two sets of industrial electron accelerators play important roles. The Electron Processing System (E.P.S), which was introduced in 1987, is a powerful electron accelerator. And the 10 MeV Accelerator, which is a traveling wave linear electron accelerator, has the higher electron energy. Both of the stes are equipped the driving devices under the beam, and has made a considerable economic results. This article describes the technology and application of the two electron accelerators. (author)

Improvement of carbon fibre surface properties using electron beam irradiation

International Nuclear Information System (INIS)

Eddy Segura Pino; Luci Diva Brocardo Machado; Claudia Giovedi

2006-01-01

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

Accelerated Electron-Beam Formation with a High Capture Coefficient in a Parallel Coupled Accelerating Structure

Science.gov (United States)

Chernousov, Yu. D.; Shebolaev, I. V.; Ikryanov, I. M.

2018-01-01

An electron beam with a high (close to 100%) coefficient of electron capture into the regime of acceleration has been obtained in a linear electron accelerator based on a parallel coupled slow-wave structure, electron gun with microwave-controlled injection current, and permanent-magnet beam-focusing system. The high capture coefficient was due to the properties of the accelerating structure, beam-focusing system, and electron-injection system. Main characteristics of the proposed systems are presented.

Direct longitudinal laser acceleration of electrons in free space

Directory of Open Access Journals (Sweden)

Sergio Carbajo

2016-02-01

Full Text Available Compact laser-driven accelerators are pursued heavily worldwide because they make novel methods and tools invented at national laboratories widely accessible in science, health, security, and technology [V. Malka et al., Principles and applications of compact laser-plasma accelerators, Nat. Phys. 4, 447 (2008]. Current leading laser-based accelerator technologies [S. P. D. Mangles et al., Monoenergetic beams of relativistic electrons from intense laser-plasma interactions, Nature (London 431, 535 (2004; T. Toncian et al., Ultrafast laser-driven microlens to focus and energy-select mega-electron volt protons, Science 312, 410 (2006; S. Tokita et al. Single-shot ultrafast electron diffraction with a laser-accelerated sub-MeV electron pulse, Appl. Phys. Lett. 95, 111911 (2009] rely on a medium to assist the light to particle energy transfer. The medium imposes material limitations or may introduce inhomogeneous fields [J. R. Dwyer et al., Femtosecond electron diffraction: “Making the molecular movie,”, Phil. Trans. R. Soc. A 364, 741 (2006]. The advent of few cycle ultraintense radially polarized lasers [S. Carbajo et al., Efficient generation of ultraintense few-cycle radially polarized laser pulses, Opt. Lett. 39, 2487 (2014] has ushered in a novel accelerator concept [L. J. Wong and F. X. Kärtner, Direct acceleration of an electron in infinite vacuum by a pulsed radially polarized laser beam, Opt. Express 18, 25035 (2010; F. Pierre-Louis et al. Direct-field electron acceleration with ultrafast radially polarized laser beams: Scaling laws and optimization, J. Phys. B 43, 025401 (2010; Y. I. Salamin, Electron acceleration from rest in vacuum by an axicon Gaussian laser beam, Phys. Rev. A 73, 043402 (2006; C. Varin and M. Piché, Relativistic attosecond electron pulses from a free-space laser-acceleration scheme, Phys. Rev. E 74, 045602 (2006; A. Sell and F. X. Kärtner, Attosecond electron bunches accelerated and

En Route: next-generation laser-plasma-based electron accelerators

International Nuclear Information System (INIS)

Hidding, Bernhard

2008-05-01

Accelerating electrons to relativistic energies is of fundamental interest, especially in particle physics. Today's accelerator technology, however, is limited by the maximum electric fields which can be created. This thesis presents results on various mechanisms aiming at exploiting the fields in focussed laser pulses and plasma waves for electron acceleration, which can be orders of magnitude higher than with conventional accelerators. With relativistic, underdense laser-plasma-interaction, quasimonoenergetic electron bunches with energies up to ∼50 MeV and normalized emittances of the order of 5mmmrad have been generated. This was achieved by focussing the ∼80 fs, 1 J pulses of the JETI-laser at the FSU Jena to intensities of several 10 19 W=cm 2 into gas jets. The experimental observations could be explained via ''bubble acceleration'', which is based on self-injection and acceleration of electrons in a highly nonlinear breaking plasma wave. For the rst time, this bubble acceleration was achieved explicitly in the self-modulated laser wakefield regime (SMLWFA). This quasimonoenergetic SMLWFA-regime stands out by relaxing dramatically the requirements on the driving laser pulse necessary to trigger bubble acceleration. This is due to self-modulation of the laser pulse in high-density gas jets, leading to ultrashort laser pulse fragments capable of initiating bubble acceleration. Electron bunches with durations < or similar 5 fs can thus be created, which is at least an order of magnitude shorter than with conventional accelerator technology. In addition, more than one laser pulse fragment can be powerful enough to drive a bubble. Distinct double peaks have been observed in the electron spectra, indicating that two quasimonoenergetic electron bunches separated by only few tens of fs have formed. This is backed up by PIC-Simulations (Particle-in-Cell). These results underline the feasibility of the construction of small table-top accelerators, while at the

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)

Standard Practice for Conducting Irradiations at Accelerator-Based Neutron Sources

CERN Document Server

American Society for Testing and Materials. Philadelphia

1996-01-01

1.1 This practice covers procedures for irradiations at accelerator-based neutron sources. The discussion focuses on two types of sources, namely nearly monoenergetic 14-MeV neutrons from the deuterium-tritium T(d,n) interaction, and broad spectrum neutrons from stopping deuterium beams in thick beryllium or lithium targets. However, most of the recommendations also apply to other types of accelerator-based sources, including spallation neutron sources (1). Interest in spallation sources has increased recently due to their proposed use for transmutation of fission reactor waste (2). 1.2 Many of the experiments conducted using such neutron sources are intended to simulate irradiation in another neutron spectrum, for example, that from a DT fusion reaction. The word simulation is used here in a broad sense to imply an approximation of the relevant neutron irradiation environment. The degree of conformity can range from poor to nearly exact. In general, the intent of these simulations is to establish the fundam...

Plasma production for electron acceleration by resonant plasma wave

International Nuclear Information System (INIS)

Anania, M.P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Croia, M.; Curcio, A.; Di Giovenale, D.; Di Pirro, G.P.; Filippi, F.; Ghigo, A.; Lollo, V.; Pella, S.; Pompili, R.; Romeo, S.; Ferrario, M.

2016-01-01

Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (10–100 GV/m), enabling acceleration of electrons to GeV energy in few centimeter. However, the quality of the electron bunches accelerated with this technique is still not comparable with that of conventional accelerators (large energy spread, low repetition rate, and large emittance); radiofrequency-based accelerators, in fact, are limited in accelerating field (10–100 MV/m) requiring therefore hundred of meters of distances to reach the GeV energies, but can provide very bright electron bunches. To combine high brightness electron bunches from conventional accelerators and high accelerating fields reachable with plasmas could be a good compromise allowing to further accelerate high brightness electron bunches coming from LINAC while preserving electron beam quality. Following the idea of plasma wave resonant excitation driven by a train of short bunches, we have started to study the requirements in terms of plasma for SPARC-LAB (Ferrario et al., 2013 [1]). In particular here we focus on hydrogen plasma discharge, and in particular on the theoretical and numerical estimates of the ionization process which are very useful to design the discharge circuit and to evaluate the current needed to be supplied to the gas in order to have full ionization. Eventually, the current supplied to the gas simulated will be compared to that measured experimentally.

Plasma production for electron acceleration by resonant plasma wave

Energy Technology Data Exchange (ETDEWEB)

Anania, M.P., E-mail: maria.pia.anania@lnf.infn.it [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); Biagioni, A.; Chiadroni, E. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); Cianchi, A. [University of Rome Tor Vergata - INFN, via della Ricerca Scientifica, 1, 00133 Roma (Italy); INFN, Via della Ricerca Scientifica, 1, 00133 Roma (Italy); Croia, M.; Curcio, A. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); University of Rome La Sapienza, Piazzale Aldo Moro, 2, 00185 Roma (Italy); Di Giovenale, D.; Di Pirro, G.P. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); Filippi, F. [University of Rome La Sapienza, Piazzale Aldo Moro, 2, 00185 Roma (Italy); Ghigo, A.; Lollo, V.; Pella, S.; Pompili, R. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); Romeo, S. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy); University of Rome La Sapienza, Piazzale Aldo Moro, 2, 00185 Roma (Italy); Ferrario, M. [INFN - LNF, via Enrico Fermi, 40, 00044 Frascati (Italy)

2016-09-01

Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (10–100 GV/m), enabling acceleration of electrons to GeV energy in few centimeter. However, the quality of the electron bunches accelerated with this technique is still not comparable with that of conventional accelerators (large energy spread, low repetition rate, and large emittance); radiofrequency-based accelerators, in fact, are limited in accelerating field (10–100 MV/m) requiring therefore hundred of meters of distances to reach the GeV energies, but can provide very bright electron bunches. To combine high brightness electron bunches from conventional accelerators and high accelerating fields reachable with plasmas could be a good compromise allowing to further accelerate high brightness electron bunches coming from LINAC while preserving electron beam quality. Following the idea of plasma wave resonant excitation driven by a train of short bunches, we have started to study the requirements in terms of plasma for SPARC-LAB (Ferrario et al., 2013 [1]). In particular here we focus on hydrogen plasma discharge, and in particular on the theoretical and numerical estimates of the ionization process which are very useful to design the discharge circuit and to evaluate the current needed to be supplied to the gas in order to have full ionization. Eventually, the current supplied to the gas simulated will be compared to that measured experimentally.

Electron irradiation-induced defects in {beta}-SiC

Energy Technology Data Exchange (ETDEWEB)

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

1996-04-01

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

Development of UV absorbing PET through Electron Irradiation

International Nuclear Information System (INIS)

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

2017-01-01

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

Startup of the Whiteshell irradiation facility

International Nuclear Information System (INIS)

Barnard, J.W.; Stanley, F.W.

1989-01-01

Recently, a 10-MeV, 1-kW electron linear accelerator was installed in a specially designed irradiation facility at the Whiteshell Nuclear Research Establishment. The facility was designed for radiation applications research in the development of new radiation processes up to the pilot scale level. The accelerator is of advanced design. Automatic startup via computer control makes it compatible with industrial processing. It has been operated successfully as a fully integrated electron irradiator for a number of applications including curing of plastics and composites, sterilization of medical disposables and animal feed irradiation. We report here on our experience during the first six months of operation. (orig.)

Startup of the whiteshell irradiation facility

Science.gov (United States)

Barnard, J. W.; Stanley, F. W.

1989-04-01

Recently, a 10-MeV, 1-kW electron linear accelerator was installed in a specially designed irradiation facility at the Whiteshell Nuclear Research Establishment. The facility was designed for radiation applications research in the development of new radiation processes up to the pilot scale level. The accelerator is of advanced design. Automatic startup via computer control makes it compatible with industrial processing. It has been operated successfully as a fully integrated electron irradiator for a number of applications including curing of plastics and composites, sterilization of medical disposables and animal feed irradiation. We report here on our experience during the first six months of operation.

Stray-electron accumulation and effects in HIF accelerators

International Nuclear Information System (INIS)

Cohen, R.H.; Friedman, A.; Furman, M.A.; Lund, S.M.; Molvik, A.W.; Stoltz, P.; Vay, J.-L.

2003-01-01

Stray electrons can be introduced in positive-charge accelerators for heavy ion fusion (or other applications) as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. Electron accumulation is impacted by the ion beam potential, accelerating fields, multipole magnetic fields used for beam focus, and the pulse duration. We highlight the distinguishing features of heavy-ion accelerators as they relate to stray-electron issues, and present first results from a sequence of simulations to characterize the electron cloud that follows from realistic ion distributions. Also, we present ion simulations with prescribed random electron distributions, undertaken to begin to quantify the effects of electrons on ion beam quality

Electron accelerators and nuclear physics

International Nuclear Information System (INIS)

Frois, B.

1989-01-01

The operating electron accelerators and their importance in the nuclear and in the particle physics developments, are underlined. The principles of probing the nucleus by applying electron scattering techniques and the main experimental results, are summarized. In order to understand hadron interactions and the dynamics of quark confinement in nuclei, the high energy electrons must provide quantitative data on the following topics: the structure of the nucleon, the role of non nucleonic components in nuclei, the nature of short-range nucleon correlations, the origin of the short-range part of nuclear forces and the effects of the nuclear medium on quark distributions. To progress in the nuclear structure knowledge it is necessary to build a coherent strategy of accelerator developments in Europe

The electron accelerator for the AWAKE experiment at CERN

Energy Technology Data Exchange (ETDEWEB)

Pepitone, K., E-mail: kevin.pepitone@cern.ch [CERN, Geneva (Switzerland); Doebert, S., E-mail: steffen.doebert@cern.ch [CERN, Geneva (Switzerland); Burt, G. [The University of Lancaster, Lancaster (United Kingdom); Chevallay, E.; Chritin, N.; Delory, C.; Fedosseev, V.; Hessler, Ch.; McMonagle, G. [CERN, Geneva (Switzerland); Mete, O. [The University of Manchester, Manchester (United Kingdom); Verzilov, V. [Triumf, Vancouver (Canada); Apsimon, R. [The University of Lancaster, Lancaster (United Kingdom)

2016-09-01

The AWAKE collaboration prepares a proton driven plasma wakefield acceleration experiment using the SPS beam at CERN. A long proton bunch extracted from the SPS interacts with a high power laser and a 10 m long rubidium vapour plasma cell to create strong wakefields allowing sustained electron acceleration. The electron bunch to probe these wakefields is supplied by a 20 MeV electron accelerator. The electron accelerator consists of an RF-gun and a short booster structure. This electron source should provide beams with intensities between 0.1 and 1 nC, bunch lengths between 0.3 and 3 ps and an emittance of the order of 2 mm mrad. The wide range of parameters should cope with the uncertainties and future prospects of the planned experiments. The layout of the electron accelerator, its instrumentation and beam dynamics simulations are presented.

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

International Nuclear Information System (INIS)

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

1998-01-01

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

Features micro plastic deformation auxetic beryllium irradiated with high-energy electrons

International Nuclear Information System (INIS)

Rarans'kij, M.D.; Olyijnich-Lisyuk, A.V.; Tashchuk, O.Yu.

2016-01-01

By low-frequency internal friction (LFIF) (1...3 Hz) method, the study of the behavior of the dynamic modulus of torsion (Gef) and by mathematical modeling of dislocation motion studied micro plastic deformation in naturally aged and irradiated with high-energy (18 MeV) electrons auxetic beryllium. With increasing doses of radiation found an increase in IF and speed of movement of dislocations in 2-3 times. Installed stage character micro strain auxetic Be. By mathematical modeling showed that in the irradiated material the deformation occurs due to the accelerated movement of the twin dislocations in the early stages, and anomalous dynamic deceleration of complete dislocations with an increase in the degree of deformation in the second stage. It is shown that theoretically estimated values are in good agreement with the experimentally determined.

Comparison of three techniques for skin total irradiation with electrons

International Nuclear Information System (INIS)

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

2011-01-01

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

Inverse Free Electron Laser accelerator

International Nuclear Information System (INIS)

Fisher, A.; Gallardo, J.; van Steenbergen, A.; Sandweiss, J.

1992-09-01

The study of the INVERSE FREE ELECTRON LASER, as a potential mode of electron acceleration, is being pursued at Brookhaven National Laboratory. Recent studies have focussed on the development of a low energy, high gradient, multi stage linear accelerator. The elementary ingredients for the IFEL interaction are the 50 MeV Linac e - beam and the 10 11 Watt CO 2 laser beam of BNL's Accelerator Test Facility (ATF), Center for Accelerator Physics (CAP) and a wiggler. The latter element is designed as a fast excitation unit making use of alternating stacks of Vanadium Permendur (VaP) ferromagnetic laminations, periodically interspersed with conductive, nonmagnetic laminations, which act as eddy current induced field reflectors. Wiggler parameters and field distribution data will be presented for a prototype wiggler in a constant period and in a ∼ 1.5 %/cm tapered period configuration. The CO 2 laser beam will be transported through the IFEL interaction region by means of a low loss, dielectric coated, rectangular waveguide. Short waveguide test sections have been constructed and have been tested using a low power cw CO 2 laser. Preliminary results of guide attenuation and mode selectivity will be given, together with a discussion of the optical issues for the IFEL accelerator. The IFEL design is supported by the development and use of 1D and 3D simulation programs. The results of simulation computations, including also wiggler errors, for a single module accelerator and for a multi-module accelerator will be presented

Electron beam irradiation to the allogeneic, xenogenic and synthetic bone materials

Energy Technology Data Exchange (ETDEWEB)

Kim, Soung Min; Park, Min Woo; Jeong, Hyun Oh [School of Dentistry Seoul National University, Seoul (Korea, Republic of); and others

2013-07-01

For the development of the biocompatible bony regeneration materials, allogenic, xenogenic and synthetic bone were irradiated by electron beam to change the basic components and structures. For the efficient electron beam irradiating condition of these allogenic, xenogenic and artificial bone substitutes, the optimal electron beam energy and their individual dose were established, to maximize the bony regeneration capacity. Commercial products of four allogenic bones, such as Accell (ISOTIS OrthogBiologics Co., USA), Allotis (Korea Bone Bank Co., Korea), Oragraft (LifeNet Co., USA), and Orthoblast (Integra Orthobiologics Inc., USA), six xenogenic bones, such as BBP (OscoTec Co., Korea), Bio-cera (OscoTec Co., Korea), Bio-oss (Geistlich Pharma AG, Switzerland), Indu-cera (OscoTec Co., Korea), OCS-B (Nibec Co., Korea), and OCS-H (Nibec Co., Korea), and six synthetic bones, such as BMP (Couellmedi Co., Korea), BoneMedik (Meta Biomed Co., Korea), Bone plus (Megagen Co., Korea), MBCP (Biomatlante Co., France), Osteon (Genoss Co., Korea), and Osteogen (Impladent LTD., USA), were used. We used 1.0 and 2.0 MeV superconduction accelerator, and/or microtrone with different individual 60, 120 kGy irradiation dose. Different dose irradiated specimens were divided 6 portions each, so total 360 groups were prepared. 4 portions were analyzed each by elementary analysis using FE-SEM (Field Emission Scanning Microscopy) and another 2 portions were grafted to the calvarial defect of Sprague-Dawley rat, following histologic, immunohistochemical analysis and TEM study were processed at the 8th and 16th weeks, in vivo. This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MEST)

Dosimetric evaluation of multi-sided irradiation on HDPE pipes under 2 MeV electron beam

Energy Technology Data Exchange (ETDEWEB)

Benny, P.G., E-mail: bennypg@yahoo.com; Khader, S.A.; Sarma, K.S.S.

2014-03-01

The use of electron beam technology has enabled the production of heat resistant pipe for hot water circulation. One of the difficulties in the irradiation of pipe products is the uneven penetration of electrons. Quality of the radiation process depends on radiation dose and homogeneity of the dose distribution, which becomes a major concern when treatments of circular objects like pipes are performed. One method to achieve uniformity in the absorbed dose in the product is to use multi-sided irradiation. The paper discusses the importance of dosimetry mapping in industrial electron beam radiation processing and outlines the challenges in delivering a uniform dose to cylindrical objects. In this study, HDPE pipe of 5 mm thickness of homogeneous material (40 mm outer diameter and 30 mm inner diameter) has been chosen for multi-sided irradiation under 2 MeV scanned electron beam from the ILU-6 accelerator. - Highlights: • The paper outlines the challenges in delivering uniform dose to cylindrical objects at 2 MeV industrial electron beam facility. • HDPE pipe of 40 mm outer diameter and 30 mm inner diameter has been chosen for the study. • The circumferential dose distribution inside and outside of the pipes were evaluated by using calibrated CTA dosimeter strips. • Using stack of dosimeter strips, changes in circumferential dose distribution in the annular region of the pipe was evaluated. • Optimization of multi-sided irradiation on the HDPE pipes for better dose homogeneity is reported in the paper.

Dosimetric evaluation of multi-sided irradiation on HDPE pipes under 2 MeV electron beam

International Nuclear Information System (INIS)

Benny, P.G.; Khader, S.A.; Sarma, K.S.S.

2014-01-01

The use of electron beam technology has enabled the production of heat resistant pipe for hot water circulation. One of the difficulties in the irradiation of pipe products is the uneven penetration of electrons. Quality of the radiation process depends on radiation dose and homogeneity of the dose distribution, which becomes a major concern when treatments of circular objects like pipes are performed. One method to achieve uniformity in the absorbed dose in the product is to use multi-sided irradiation. The paper discusses the importance of dosimetry mapping in industrial electron beam radiation processing and outlines the challenges in delivering a uniform dose to cylindrical objects. In this study, HDPE pipe of 5 mm thickness of homogeneous material (40 mm outer diameter and 30 mm inner diameter) has been chosen for multi-sided irradiation under 2 MeV scanned electron beam from the ILU-6 accelerator. - Highlights: • The paper outlines the challenges in delivering uniform dose to cylindrical objects at 2 MeV industrial electron beam facility. • HDPE pipe of 40 mm outer diameter and 30 mm inner diameter has been chosen for the study. • The circumferential dose distribution inside and outside of the pipes were evaluated by using calibrated CTA dosimeter strips. • Using stack of dosimeter strips, changes in circumferential dose distribution in the annular region of the pipe was evaluated. • Optimization of multi-sided irradiation on the HDPE pipes for better dose homogeneity is reported in the paper

Induced radioactivity of materials by stray radiation fields at an electron accelerator

CERN Document Server

Rokni, S H; Gwise, T; Liu, J C; Roesler, S

2002-01-01

Samples of soil, water, aluminum, copper and iron were irradiated in the stray radiation field generated by the interaction of a 28.5 GeV electron beam in a copper-dump in the Beam Dump East facility at the Stanford Linear Accelerator Center. The specific activity induced in the samples was measured by gamma spectroscopy and other techniques. In addition, the isotope production in the samples was calculated with detailed Monte Carlo simulations using the FLUKA code. The calculated activities are compared to the experimental values and differences are discussed.

Unified 1.9...4.0 MeV linear accelerators with interchangeable accelerating structures for customs inspection

International Nuclear Information System (INIS)

Budtov, A.A.; Klinov, A.P.; Krestianinov, A.S.

2004-01-01

A series of compact linear electron accelerators for 1.9, 2.5 and 4.0 MeV equipped with a local radiation shielding has been designed and constructed in the NPK LUTS, the D.V.Efremov Institute (NIIEFA). The accelerators are intended for mobile facilities used for customs inspection of large-scale containers. Results of optimizing calculations of irradiator parameters and electron dynamics, verified under accelerators testing, are presented in the report. The main design approaches allowing the construction of unified accelerators with interchangeable accelerating structures for energies in the range of 1.9...4.0 MeV are also given

Apparatus for electron beam irradiation of objects

International Nuclear Information System (INIS)

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

1984-01-01

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

Present state of works on development of electron accelerators for energy consuming processes at Efremov Research Institute

Energy Technology Data Exchange (ETDEWEB)

Ivanov, A. S.; Maznev, V. P.; Ovchinnikov, V. P.; Svinin, M. P.; Tolstun, N. G. [Efremov Research Institute of Electrophysical Apparatus, Saint-Petersburg (Russian Federation)

2011-07-01

Necessity to decrease anthropogenic environmental pollution puts a task of development of HV accelerators for introduction of nature conservation technologies in commercial scale. High efficiency and operation reliability in a power range noticeably higher than already mastered level are required. In design of the accelerators basic units, namely, HV generators, accelerating structures, electron beam irradiation field forming systems and extraction devices solutions that demonstrated already theirs operational capacity in the machines of a lesser power may be used. From the other hand, experience gained by already full-scale built powerful installations shows that a number of problems remain unsolved that put obstacles on a way of wide implementation of exhaust gases irradiation processing. Attempts to built the accelerator meeting all requirements in a frame of specific contracts, although already shown noticeable progress in a sense of the power grow, acquiring of very valuable experience, carry some risk caused by insufficient study of the problems connected with power increasing, lack of time and means for the thorough research works. It looks reasonable to suggest creation of full-scale pilot installation with HV accelerator of required power (1 MW, for example) not bound to a specific commercial contract, where researches and studies of the accelerator main systems, theirs optimization and longevity tests can be carried out thus providing development of the accelerator into really reliable and effective tool for applying to environmental tasks.

Multistage linear electron acceleration using pulsed transmission lines

International Nuclear Information System (INIS)

Miller, R.B.; Prestwich, K.R.; Poukey, J.W.; Epstein, B.G.; Freeman, J.R.; Sharpe, A.W.; Tucker, W.K.; Shope, S.L.

1981-01-01

A four-stage linear electron accelerator is described which uses pulsed radial transmission lines as the basic accelerating units. An annular electron beam produced by a foilless diode is guided through the accelerator by a strong axial magnetic field. Synchronous firing of the injector and the acccelerating modules is accomplished with self-breaking oil switches. The device has accelerated beam currents of 25 kA to kinetic energies of 9 MV, with 90% current transport efficiency. The average accelerating gradient is 3 MV/m

Initial investigations of dose distribution patterns for an industrial electron accelerator

International Nuclear Information System (INIS)

Ehlermann, D.A.E.

1994-01-01

A newly developed accelerator for electrons in the dose range of up 10 mev at 10 kw performance replaces a similar type of accelerator that has been in use during the past 25 years. It is characterized by some decisive technical changes. The ray, rather than moving from one point to the next, is now distributed over the merchandise for the duration of an impulse. In the direction of conveyance, irradiation is carried out on successive fields as was done formerly. As the duration of impulse is no longer than 12 μs, some problems arose in respect of operation and measuring techniques: the time distribution of microwave energy or rays emitted during the individual impulses has a bearing on the dose distribution pattern at a right angle to the direction of transport in both the superficial and deep layers of the merchandise. Some of the initial measuring results are represented here. The accelerator's operational parameters were then so adjusted that a largely homogeneous dose distribution was achieved throughout. (orig.) [de

Electron cloud dynamics in the Cornell Electron Storage Ring Test Accelerator wiggler

Directory of Open Access Journals (Sweden)

C. M. Celata

2011-04-01

Full Text Available The interference of stray electrons (also called “electron clouds” with accelerator beams is important in modern intense-beam accelerators, especially those with beams of positive charge. In magnetic wigglers, used, for instance, for transverse emittance damping, the intense synchrotron radiation produced by the beam can generate an electron cloud of relatively high density. In this paper the complicated dynamics of electron clouds in wigglers is examined using the example of a wiggler in the Cornell Electron Storage Ring Test Accelerator experiment at the Cornell Electron Storage Ring. Three-dimensional particle-in-cell simulations with the WARP-POSINST computer code show different density and dynamics for the electron cloud at locations near the maxima of the vertical wiggler field when compared to locations near the minima. Dynamics in these regions, the electron cloud distribution vs longitudinal position, and the beam coherent tune shift caused by the wiggler electron cloud will be discussed.

Calorimetry at industrial electron accelerators

DEFF Research Database (Denmark)

Miller, Arne; Kovacs, A.

1985-01-01

Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials such as grap......Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials...

Food irradiation by low energy electrons

International Nuclear Information System (INIS)

Bird, J.R.

1985-01-01

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

Solution of the transport problem for electrons generated by an accelerator in the three-dimensional space of an absorber

International Nuclear Information System (INIS)

Vinogradov, V.V.

1981-01-01

The purpose of the investigation is the development of the method for calculation of distribution function of particles in the medium irradiated by electron beams. The process of particle transport was considered for infinite isotropic medium under the condition that all the particles, are concentrated in the source at first. The obtained solution can be used for investigation of particle transport through the substance with account of geometry of electron beam, particle distribution by the beam cross section, energy and angular spectra. The suggested approach can be applied for the solution of transport problems in which geometry of irradiated surface, presence of the field in the absorber should be taken into account that is significant when using electron accelerators in applied purposes [ru

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

International Nuclear Information System (INIS)

Meri Suhartini

2004-01-01

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

Study and realization of an electron linear accelerator. Dynamics of accelerated electrons; Etude et realisation d'un accelerateur lineaire d'electrons. Dynamique des electrons acceleres

Energy Technology Data Exchange (ETDEWEB)

Bernard, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-04-01

The theoretical characteristics of the electron linear accelerator are: 30 MeV for the energy W{sub S} and 250 mA for the peak current I{sub c}. The main utilization is the intense production of fast neutrons by the reactions ({gamma},n) and ({gamma},f) induced in a target of natural uranium by the accelerated electrons. In the first part of the thesis, relative to the study and the realization of the accelerator, a new equation of dispersion is established analytically when the guide is loaded with round-edged irises. The relation is compared with the equation established by CHU and Hansen, WALKINSHAW, KVASIL in the case of a guide loaded with flat-edged irises. The experimental and theoretical curves of dispersion are compared. The accuracy of every relation of dispersion is estimated. The second part of the thesis is relative to the theoretical study of the electrons dynamics in the guide; it allows the derivation of the parameters of the beam: dispersion of phase, energy, dispersion of energy and the relation W{sub S} = f (I{sub c}). The results relative to the first experiments are given and compared with the theoretical expectations. (author) [French] Les caracteristiques nominales theoriques de l'accelerateur lineaire d'electrons sont: 30 MeV pour l'energie W{sub S} et 250 mA pour le courant de crete I{sub c}. L'utilisation principale envisagee est la production de neutrons rapides par les reactions ({gamma},n) et ({gamma},f) induites dans une cible d'uranium naturel par les electrons acceleres. Dans la premiere partie de la these relative a l'elude et a la realisation de l'accelerateur, une nouvelle equation de dispersion (ou equation aux frequences) est etablie analytiquement pour un guide charge par des iris a bord rond. Cette relation est comparee a celles etablies par CHU et HANSEN, WALKINSHAW, KVASIL dans le cas du guide charge par des iris a bord plat. On compare les courbes de dispersion theoriques et experimentales et on evalue la precision de

Issues for Bringing Electron Beam Irradiators On-Line

International Nuclear Information System (INIS)

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

1999-01-01

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

Issues for Bringing Electron Beam Irradiators On-Line

Energy Technology Data Exchange (ETDEWEB)

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

1999-04-20

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

Electron cyclotron wave acceleration outside a flaring loop

Science.gov (United States)

Sprangle, P.; Vlahos, L.

1983-01-01

A model for the secondary acceleration of electrons outside a flaring loop is proposed. The results suggest that the narrow bandwidth radiation emitted by the unstable electron distribution inside a flaring loop can become the driver for secondary electron acceleration outside the loop. It is shown that a system of electrons gyrating about and streaming along an adiabatically spatially varying, static magnetic field can be efficiently accelerated to high energies by an electromagnetic wave propagating along and polarized transverse to the static magnetic field. The predictions from our model appear to be in general agreement with existing observations.

Electron cyclotron wave acceleration outside a flaring loop

International Nuclear Information System (INIS)

Sprangle, P.; Vlahos, L.

1983-01-01

We propose a model for the secondary acceleration of electrons outside a flaring loop. Our results suggest that the narrow bandwidth radiation emitted by the unstable electron distribution inside a flaring loop can become the driver for secondary electron acceleration outside the loop. We show that a system of electrons gyrating about and streaming along an adiabatically spatially varying, static magnetic field can be efficiently accelerated to high energies by an electromagnetic wave propagating along and polarized transverse to the static magnetic field. The predictions from our model appear to be in general agreement with existing observations

Nonponderomotive electron acceleration in ultrashort surface-plasmon fields

Energy Technology Data Exchange (ETDEWEB)

Racz, Peter; Dombi, Peter [Wigner Research Centre for Physics, Konkoly-Thege M. ut 29-33, H-1121 Budapest (Hungary)

2011-12-15

We investigate the nonponderomotive nature of ultrafast plasmonic electron acceleration in strongly decaying electromagnetic fields generated by few-cycle and single-cycle femtosecond laser pulses. We clearly identify the conditions contributing to nonponderomotive acceleration and establish fundamental scaling laws and carrier-envelope phase effects. These all-optically accelerated compact, femtosecond electron sources can be utilized in contemporary ultrafast methods.

Electronics around the accelerators- mathematical recalls

International Nuclear Information System (INIS)

Le Meur, G.

1992-02-01

The author presents the main mathematical tools used in electronics and in particular in accelerator electronics: complex functions, distributions, Fourier series, Laplace transformation, Fourier transformation and probabilities

Accelerator conceptual design of the international fusion materials irradiation facility

International Nuclear Information System (INIS)

Sugimoto, M.; Kinsho, M.; Teplyakov, V.; Berwald, D.; Bruhwiler, D.; Peakock, M.; Rathke, J.; Deitinghoff, H.; Klein, H.; Pozimski, Y.; Volk, K.; Miyahara, A.; Olivier, M.; Piechowiak, E.; Tanabe, Y.

1998-01-01

The accelerator system of the international fusion materials irradiation facility (IFMIF) provides the 250-mA, 40-MeV continuous-wave deuteron beam at one of the two lithium target stations. It consists of two identical linear accelerator modules, each of which independently delivers a 125-mA beam to the common footprint of 20 cm x 5 cm at the target surface. The accelerator module consists of an ion injector, a 175 MHz RFQ and eight DTL tanks, and rf power supply system. The requirements for the accelerator system and the design concept are described. The interface issues and operational considerations to attain the proposed availability are also discussed. (orig.)

Beam dosimetry in high-power electron accelerators

International Nuclear Information System (INIS)

Popov, V.N.; Zhitomirskii, B.M.; Ermakov, A.N.; Terebilin, A.V.; Stryukov, V.A.

1987-01-01

In order to evaluate beam utilization efficiency, measure the radiation yield, and determine the cost effectiveness of the new technologies, it is necessary to know the radiation power of the electron beam absorbed by the reacting medium. To measure the electron-beam power the authors designed, built, and tested a radiation detector combining a Faraday cylinder with a continuous-flow calorimeter. The construction of the detector is shown. The radiation detector was tested on a number of electron accelerators. The beam-power and mean-electron-energy measurement results for the LUE-8M accelerator with 8 MeV maximum electron energy are given

Utilization of electron beam accelerators for polymer processing

International Nuclear Information System (INIS)

Sarma, K.S.S.

2013-01-01

During the last decade, electron beam processing has been amply demonstrated to the Indian cable industry by BARC using 2 MeV/20 kW electron beam (EB) accelerator (ILU-6 EBA facility) located at BARC-BRIT complex, Vashi. The electron beam accelerator is a machine producing high energy electrons which are made to impinge on the materials for inducing physical, chemical and biological modifications. The process is carried out at room temperature and in ambient atmospheric conditions. Lately, quite a few numbers of accelerators have been installed by the private cable industry and carrying out cross-linking of cable insulations for high performance viz. high temperature stability, good flame retardancy, lesser solvent-swelling, thinner insulations etc. The indigenously made accelerators at EB centre, particularly the 3 MeV/30 kW accelerator will be of much help for Indian industry for polymer processing as the market is poised to grow by adapting the technology

Impact of accelerated electrons on activating process and foaming potential of sludge

International Nuclear Information System (INIS)

Cuba, V.; Pospisil, M.; Mucka, V.; Silber, R.; Jenicek, P.; Dohanyos, M.; Zabranska, J.

2002-01-01

Complete text of publication follows. Presently, anaerobic and/or aerobic biological treatment is the cheapest and the most effective method of wastewater and sludge processing. However, due to some non-biodegradable substances present in wastewater and also due to limited capacity of wastewater treatment plants, it is necessary to find effective processes, that would be complementary to existing sludge treatment methods. Beside chemical and physical processes, radiation technology seems to offer improvement of effectivity of biological treatment. The paper describes possibilities of irradiation in activating process. Activated sludge can be affected in all its parameters, including physico chemical properties, such as sedimentation rate, or resulting volume of sludge. For the purpose of this research, laboratory experimental reactors simulating activating process were operated. According to previous results, accelerated electrons were used for irradiation, for e-beam seems to be more expedient than gamma irradiation. Reactor with irradiated sludge has been compared with the one without irradiation. It is shown, that pre-irradiation of sludge can positively affect following process of activation. Beside the activating process, another goal has been pursued. Radiation can strongly affect sludge foaming potential. Biological foaming caused by surfactant microorganisms, represents quite serious problem in many wastewater treatment plants, especially in digesters. It was proved that after irradiation foaming potential of sludge decreases. Pre-irradiation of activated sludge with relatively low doses also results in reduction of number of pathogenic microorganisms, presented in sludge

Microstructural Parameters in 8 MeV Electron-Irradiated BOMBYX MORI Silk Fibers by Wide-ANGLE X-Ray Scattering Studies (waxs)

Science.gov (United States)

Sangappa, Asha, S.; Sanjeev, Ganesh; Subramanya, G.; Parameswara, P.; Somashekar, R.

2010-01-01

The present work looks into the microstructural modification in electron irradiated Bombyx mori P31 silk fibers. The irradiation process was performed in air at room temperature using 8 MeV electron accelerator at different doses: 0, 25, 50 and 100 kGy. Irradiation of polymer is used to cross-link or degrade the desired component or to fix the polymer morphology. The changes in microstructural parameters in these natural polymer fibers have been computed using wide angle X-ray scattering (WAXS) data and employing line profile analysis (LPA) using Fourier transform technique of Warren. Exponential, Lognormal and Reinhold functions for the column length distributions have been used for the determination of crystal size, lattice strain and enthalpy parameters.

An inverse free electron laser accelerator experiment

International Nuclear Information System (INIS)

Wernick, I.; Marshall, T.C.

1992-01-01

A free electron laser was configured as an autoaccelerator to test the principle of accelerating electrons by stimulated absorption of radiation (λ = 1.65mm) by an electron beam (750kV) traversing an undulator. Radiation is produced in the first section of a constant period undulator (1 w1 = 1.43cm) and then absorbed (∼ 40%) in a second undulator, having a tapered period (1 w2 = 1.8 - 2.25cm), which results in the acceleration of a subgroup (∼ 9%) of electrons to ∼ 1MeV

Polyurethanes irradiation by accelerated electrons: molecular and supramolecular evolution, incidence on the extractable and biomedical implications

International Nuclear Information System (INIS)

Guignot, C.

2002-11-01

Face to the development of radiosterilization and polymers medical devices it was wished to study the behavior of polyurethanes under accelerated electrons in oxidizing atmosphere. This study has been made to reveal the physico chemical and organisational modifications of polyurethanes for a medical use. (N.C.)

Effect of electron beam irradiation on seed germination

Energy Technology Data Exchange (ETDEWEB)

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

2013-07-01

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

Effect of electron beam irradiation on seed germination

International Nuclear Information System (INIS)

Han, Seunghee; Bae, Youngmin

2013-01-01

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

Implementation of the technique of partial irradiation accelerated the breast with high doses (HDR) brachytherapy

International Nuclear Information System (INIS)

Molina Lopez, M. Y.; Pardo Perez, E.; Castro Novais, J.; Martinez Ortega, J.; Ruiz Maqueda, S.; Cerro Penalver, E. del

2013-01-01

The objective of this work is presents procedure carried out in our Centre for the implementation of the accelerated partial breast irradiation (APBI, accelerated partial-breast irradiation) with high-rate brachytherapy (HDR), using plastic tubes as applicators. Carried out measures, the evaluation of the dosimetric parameters analyzing and presenting the results. (Author)

Effects of Shock and Turbulence Properties on Electron Acceleration

Science.gov (United States)

Qin, G.; Kong, F.-J.; Zhang, L.-H.

2018-06-01

Using test particle simulations, we study electron acceleration at collisionless shocks with a two-component model turbulent magnetic field with slab component including dissipation range. We investigate the importance of the shock-normal angle θ Bn, magnetic turbulence level {(b/{B}0)}2, and shock thickness on the acceleration efficiency of electrons. It is shown that at perpendicular shocks the electron acceleration efficiency is enhanced with the decrease of {(b/{B}0)}2, and at {(b/{B}0)}2=0.01 the acceleration becomes significant due to a strong drift electric field with long time particles staying near the shock front for shock drift acceleration (SDA). In addition, at parallel shocks the electron acceleration efficiency is increasing with the increase of {(b/{B}0)}2, and at {(b/{B}0)}2=10.0 the acceleration is very strong due to sufficient pitch-angle scattering for first-order Fermi acceleration, as well as due to the large local component of the magnetic field perpendicular to the shock-normal angle for SDA. On the other hand, the high perpendicular shock acceleration with {(b/{B}0)}2=0.01 is stronger than the high parallel shock acceleration with {(b/{B}0)}2=10.0, the reason might be the assumption that SDA is more efficient than first-order Fermi acceleration. Furthermore, for oblique shocks, the acceleration efficiency is small no matter whether the turbulence level is low or high. Moreover, for the effect of shock thickness on electron acceleration at perpendicular shocks, we show that there exists the bendover thickness, L diff,b. The acceleration efficiency does not noticeably change if the shock thickness is much smaller than L diff,b. However, if the shock thickness is much larger than L diff,b, the acceleration efficiency starts to drop abruptly.