WorldWideScience

Sample records for applying advanced neutron

  1. Advances in neutron tomography

    Indian Academy of Sciences (India)

    W Treimer

    2008-11-01

    In the last decade neutron radiography (NR) and tomography (NCT) have experienced a number of improvements, due to the well-known properties of neutrons interacting with matter, i.e. the low attenuation by many materials, the strong attenuation by hydrogenous constituent in samples, the wavelength-dependent attenuation in the neighbourhood of Bragg edges and due to better 2D neutron detectors. So NR and NCT were improved by sophisticated techniques that are based on the attenuation of neutrons or on phase changes of the associated neutron waves if they pass through structured materials. Up to now the interaction of the neutron spin with magnetic fields in samples has not been applied to imaging techniques despite the fact that it was proposed many years ago. About ten years ago neutron depolarization as imaging signal for neutron radiography or tomography was demonstrated and in principle it works. Now one can present much improved test experiments using polarized neutrons for radiographic imaging. For this purpose the CONRAD instrument of the HMI was equipped with polarizing and analysing benders very similar to conventional scattering experiments using polarized neutrons. Magnetic fields in different coils and in samples (superconductors) at low temperatures could be visualized. In this lecture a summary about standard signals (attenuation) and the more `sophisticated' imaging signals as refraction, small angle scattering and polarized neutrons will be given.

  2. Applied neutron resonance theory

    International Nuclear Information System (INIS)

    Utilisation of resonance theory in basic and applications-oriented neutron cross section work is reviewed. The technically important resonance formalisms, principal concepts and methods as well as representative computer programs for resonance parameter extraction from measured data, evaluation of resonance data, calculation of Doppler-broadened cross sections and estimation of level-statistical quantities from resonance parameters are described. (orig.)

  3. Advances in Applied Mechanics

    OpenAIRE

    2014-01-01

    Advances in Applied Mechanics draws together recent significant advances in various topics in applied mechanics. Published since 1948, Advances in Applied Mechanics aims to provide authoritative review articles on topics in the mechanical sciences, primarily of interest to scientists and engineers working in the various branches of mechanics, but also of interest to the many who use the results of investigations in mechanics in various application areas, such as aerospace, chemical, civil, en...

  4. Recent advances in neutron tomography

    International Nuclear Information System (INIS)

    Neutron imaging has been shown to be an excellent imaging tool for many nondestructive evaluation applications. Significantly improved contrast over X-ray images is possible for materials commonly found in engineering assemblies. The major limitations have been the neutron source and detection. A low cost, position sensitive neutron tomography detector system has been designed and built based on an electro-optical detector system using a LiF-ZnS scintillator screen and a cooled charge coupled device. This detector system can be used for neutron radiography as well as two and three-dimensional neutron tomography. Calculated performance of the system predicted near-quantum efficiency for position sensitive neutron detection. Experimental data was recently taken using this system at McClellan Air Force Base, Air Logistics Center, Sacramento, CA. With increased availability of low cost neutron sources and advanced image processing, neutron tomography will become an increasingly important nondestructive imaging method

  5. Boron neutron capture therapy applied to advanced breast cancers: Engineering simulation and feasibility study of the radiation treatment protocol

    Science.gov (United States)

    Sztejnberg Goncalves-Carralves, Manuel Leonardo

    This dissertation describes a novel Boron Neutron Capture Therapy (BNCT) application for the treatment of human epidermal growth factor receptor type 2 positive (HER2+) breast cancers. The original contribution of the dissertation is the development of the engineering simulation and the feasibility study of the radiation treatment protocol for this novel combination of BNCT and HER2+ breast cancer treatment. This new concept of BNCT, representing a radiation binary targeted treatment, consists of the combination of two approaches never used in a synergism before. This combination may offer realistic hope for relapsed and/or metastasized breast cancers. This treatment assumes that the boronated anti-HER2 monoclonal antibodies (MABs) are administrated to the patient and accumulate preferentially in the tumor. Then the tumor is destroyed when is exposed to neutron irradiation. Since the use of anti-HER2 MABs yields good and promising results, the proposed concept is expected to amplify the known effect and be considered as a possible additional treatment approach to the most severe breast cancers for patients with metastasized cancer for which the current protocol is not successful and for patients refusing to have the standard treatment protocol. This dissertation makes an original contribution with an integral numerical approach and proves feasible the combination of the aforementioned therapy and disease. With these goals, the dissertation describes the theoretical analysis of the proposed concept providing an integral engineering simulation study of the treatment protocol. An extensive analysis of the potential limitations, capabilities and optimization factors are well studied using simplified models, models based on real CT patients' images, cellular models, and Monte Carlo (MCNP5/X) transport codes. One of the outcomes of the integral dosimetry assessment originally developed for the proposed treatment of advanced breast cancers is the implementation of BNCT

  6. Development of advanced neutron beam technology

    Energy Technology Data Exchange (ETDEWEB)

    Seong, B. S.; Lee, J. S.; Sim, C. M. (and others)

    2007-06-15

    The purpose of this work is to timely support the national science and technology policy through development of the advanced application techniques for neutron spectrometers, built in the previous project, in order to improve the neutron spectrometer techniques up to the world-class level in both quantity and quality and to reinforce industrial competitiveness. The importance of the research and development (R and D) is as follows: 1. Technological aspects - Development of a high value-added technology through performing the advanced R and D in the broad research areas from basic to applied science and from hard to soft condensed matter using neutron scattering technique. - Achievement of an important role in development of the new technology for the following industries aerospace, defense industry, atomic energy, hydrogen fuel cell etc. by the non-destructive inspection and analysis using neutron radiography. - Development of a system supporting the academic-industry users for the HANARO facility 2. Economical and Industrial Aspects - Essential technology in the industrial application of neutron spectrometer, in the basic and applied research of the diverse materials sciences, and in NT, BT, and IT areas - Broad impact on the economics and the domestic and international collaborative research by using the neutron instruments in the mega-scale research facility, HANARO, that is a unique source of neutron in Korea. 3. Social Aspects - Creating the scientific knowledge and contributing to the advanced industrial society through the neutron beam application - Improving quality of life and building a national consensus on the application of nuclear power by developing the RT fusion technology using the HANARO facility. - Widening the national research area and strengthening the national R and D capability by performing advanced R and D using the HANARO facility.

  7. Development of advanced neutron beam technology

    International Nuclear Information System (INIS)

    The purpose of this work is to timely support the national science and technology policy through development of the advanced application techniques for neutron spectrometers, built in the previous project, in order to improve the neutron spectrometer techniques up to the world-class level in both quantity and quality and to reinforce industrial competitiveness. The importance of the research and development (R and D) is as follows: 1. Technological aspects - Development of a high value-added technology through performing the advanced R and D in the broad research areas from basic to applied science and from hard to soft condensed matter using neutron scattering technique. - Achievement of an important role in development of the new technology for the following industries aerospace, defense industry, atomic energy, hydrogen fuel cell etc. by the non-destructive inspection and analysis using neutron radiography. - Development of a system supporting the academic-industry users for the HANARO facility 2. Economical and Industrial Aspects - Essential technology in the industrial application of neutron spectrometer, in the basic and applied research of the diverse materials sciences, and in NT, BT, and IT areas - Broad impact on the economics and the domestic and international collaborative research by using the neutron instruments in the mega-scale research facility, HANARO, that is a unique source of neutron in Korea. 3. Social Aspects - Creating the scientific knowledge and contributing to the advanced industrial society through the neutron beam application - Improving quality of life and building a national consensus on the application of nuclear power by developing the RT fusion technology using the HANARO facility. - Widening the national research area and strengthening the national R and D capability by performing advanced R and D using the HANARO facility

  8. Advanced Neutron Spectrometer

    Science.gov (United States)

    Christl, Mark; Dobson, Chris; Norwood, Joseph; Kayatin, Matthew; Apple, Jeff; Gibson, Brian; Dietz, Kurt; Benson, Carl; Smith, Dennis; Howard, David; Rodriquez, Miguel; Watts, John; Sabra, Mohammed; Kuznetsov, Evgeny

    2013-01-01

    Energetic neutron measurements remain a challenge for space science investigations and radiation monitoring for human exploration beyond LEO. We are investigating a new composite scintillator design that uses Li6 glass scintillator embedded in a PVT block. A comparison between Li6 and Boron 10 loaded scintillators are being studied to assess the advantages and shortcomings of these two techniques. We present the details of the new Li6 design and results from the comparison of the B10 and Li6 techniques during exposures in a mixed radiation field produced by high energy protons interacting in a target material.

  9. (International Collaboration on Advanced Neutron Sources)

    Energy Technology Data Exchange (ETDEWEB)

    Hayter, J.B.

    1990-11-08

    The International Collaboration on Advanced Neutron Sources was started about a decade ago with the purpose of sharing information throughout the global neutron community. The collaboration has been extremely successful in optimizing the use of resources, and the discussions are open and detailed, with reasons for failure shared as well as reasons for success. Although the meetings have become increasingly oriented toward pulsed neutron sources, many of the neutron instrumentation techniques, such as the development of better monochromators, fast response detectors and various data analysis methods, are highly relevant to the Advanced Neutron Source (ANS). I presented one paper on the ANS, and another on the neutron optical polarizer design work which won a 1989 R D-100 Award. I also gained some valuable design ideas, in particular for the ANS hot source, in discussions with individual researchers from Canada, Western Europe, and Japan.

  10. Computed neutron coincidence counting applied to passive waste assay

    Energy Technology Data Exchange (ETDEWEB)

    Bruggeman, M.; Baeten, P.; De Boeck, W.; Carchon, R. [Nuclear Research Centre, Mol (Belgium)

    1997-11-01

    Neutron coincidence counting applied for the passive assay of fissile material is generally realised with dedicated electronic circuits. This paper presents a software based neutron coincidence counting method with data acquisition via a commercial PC-based Time Interval Analyser (TIA). The TIA is used to measure and record all time intervals between successive pulses in the pulse train up to count-rates of 2 Mpulses/s. Software modules are then used to compute the coincidence count-rates and multiplicity related data. This computed neutron coincidence counting (CNCC) offers full access to all the time information contained in the pulse train. This paper will mainly concentrate on the application and advantages of CNCC for the non-destructive assay of waste. An advanced multiplicity selective Rossi-alpha method is presented and its implementation via CNCC demonstrated. 13 refs., 4 figs., 2 tabs.

  11. Computed neutron coincidence counting applied to passive waste assay

    International Nuclear Information System (INIS)

    Neutron coincidence counting applied for the passive assay of fissile material is generally realised with dedicated electronic circuits. This paper presents a software based neutron coincidence counting method with data acquisition via a commercial PC-based Time Interval Analyser (TIA). The TIA is used to measure and record all time intervals between successive pulses in the pulse train up to count-rates of 2 Mpulses/s. Software modules are then used to compute the coincidence count-rates and multiplicity related data. This computed neutron coincidence counting (CNCC) offers full access to all the time information contained in the pulse train. This paper will mainly concentrate on the application and advantages of CNCC for the non-destructive assay of waste. An advanced multiplicity selective Rossi-alpha method is presented and its implementation via CNCC demonstrated. 13 refs., 4 figs., 2 tabs

  12. The neutron texture diffractometer at the China Advanced Research Reactor

    Science.gov (United States)

    Li, Mei-Juan; Liu, Xiao-Long; Liu, Yun-Tao; Tian, Geng-Fang; Gao, Jian-Bo; Yu, Zhou-Xiang; Li, Yu-Qing; Wu, Li-Qi; Yang, Lin-Feng; Sun, Kai; Wang, Hong-Li; Santisteban, J. r.; Chen, Dong-Feng

    2016-03-01

    The first neutron texture diffractometer in China has been built at the China Advanced Research Reactor, due to strong demand for texture measurement with neutrons from the domestic user community. This neutron texture diffractometer has high neutron intensity, moderate resolution and is mainly applied to study texture in commonly used industrial materials and engineering components. In this paper, the design and characteristics of this instrument are described. The results for calibration with neutrons and quantitative texture analysis of zirconium alloy plate are presented. The comparison of texture measurements with the results obtained in HIPPO at LANSCE and Kowari at ANSTO illustrates the reliability of the texture diffractometer. Supported by National Nature Science Foundation of China (11105231, 11205248, 51327902) and International Atomic Energy Agency-TC program (CPR0012)

  13. Advanced Neutron Source (ANS) Project progress report

    International Nuclear Information System (INIS)

    This report discusses the following topics on the advanced neutron source: quality assurance (QA) program; reactor core development; fuel element specification; corrosion loop tests and analyses; thermal-hydraulic loop tests; reactor control concepts; critical and subcritical experiments; material data, structural tests, and analysis; cold source development; beam tube, guide, and instrument development; hot source development; neutron transport and shielding; I ampersand C research and development; facility concepts; design; and safety

  14. Advanced Neutron Source (ANS) Project progress report

    Energy Technology Data Exchange (ETDEWEB)

    McBee, M.R.; Chance, C.M. (eds.) (Oak Ridge National Lab., TN (USA)); Selby, D.L.; Harrington, R.M.; Peretz, F.J. (Oak Ridge National Lab., TN (USA))

    1990-04-01

    This report discusses the following topics on the advanced neutron source: quality assurance (QA) program; reactor core development; fuel element specification; corrosion loop tests and analyses; thermal-hydraulic loop tests; reactor control concepts; critical and subcritical experiments; material data, structural tests, and analysis; cold source development; beam tube, guide, and instrument development; hot source development; neutron transport and shielding; I C research and development; facility concepts; design; and safety.

  15. Advanced Neutron Source (ANS) Project

    International Nuclear Information System (INIS)

    This report covers the progress made in 1993 in the following sections: (1) project management; (2) research and development; (3) design and (4) safety. The section on research and development covers the following: (1) reactor core development; (2) fuel development; (3) corrosion loop tests and analysis; (4) thermal-hydraulic loop tests; (5) reactor control and shutdown concepts; (6) critical and subcritical experiments; (7) material data, structure tests, and analysis; (8) cold source development; (9) beam tube, guide, and instrument development; (10) neutron transport and shielding; (11) I and C research and development; and (12) facility concepts

  16. Albedo method applied to coupled neutron-gamma shielding radiations

    International Nuclear Information System (INIS)

    The Albedo Theory was applied in order to develop an one-group algorithm for coupled neutron-gamma shielding calculations. The configuration analyzed consists of multilayered plane systems, where a incident neutron current generates gamma radiation through neutron-gamma reactions. The results obtained by Albedo Method and ANISN code have shown excellent agreement. (author)

  17. ALADIN - Advanced Laue Diffraction Instruments using Neutrons

    International Nuclear Information System (INIS)

    Laue diffraction techniques have proven to be very attractive to a broad user community interested in obtaining detailed structural information on very small single-crystal samples or needing data collection speeds comparable to those available with the powder diffraction technique. However our experience has clearly demonstrated the negative effect of up-stream monochromatic instruments on the quality of Laue data. In order to obtain Laue diffraction data with a statistical accuracy similar to that achieved on a monochromatic instrument (neutron or X-rays), the project ALADIN (for Advanced Laue Diffraction Instruments using Neutrons) aims to: -) construct a Laue-dedicated thermal neutron guide, with m=2 super-mirror coating, providing access to the desirable wavelength bandwidth; -) installation of one of the ILL Laue diffractometers (VIVALDI or CYCLOPS) on this new guide. (authors)

  18. Advanced Neutron Source: Plant Design Requirements

    Energy Technology Data Exchange (ETDEWEB)

    1990-07-01

    The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS.

  19. Advanced Neutron Source: Plant Design Requirements

    International Nuclear Information System (INIS)

    The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS

  20. Advancement of German Neutron Spectrometers Relocation Project in 2008

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Neutron scattering technique is going on in Neutron Scattering Laboratory (NSL) of China Institute of Atomic Energy (CIAE) based on China Advanced Research Reactor (CARR), which will be hopefully

  1. The advanced neutron source research and development plan

    Energy Technology Data Exchange (ETDEWEB)

    Selby, D.L.

    1995-08-01

    The Advanced Neutron Source (ANS) is being designed as a user-oriented neutron research laboratory centered around the most intense continuous beams of thermal and subthermal neutrons in the world (an order of magnitude more intense than beams available from the most advanced existing reactors). The ANS will be built around a new research reactor of 330-MW fission power, producing an unprecedented peak thermal flux of >7 {center_dot} 10{sup 19} {center_dot} m{sup -2} {center_dot} s{sup -1}. Primarily a research facility, the ANS will accommodate more than 1000 academic, industrial, and government researchers each year. They will conduct basic research in all branches of science as well as applied research leading to better understanding of new materials, including high temperature super conductors, plastics, and thin films. Some 48 neutron beam stations will be set up in the ANS beam rooms and the neutron guide hall for neutron scattering and for fundamental and nuclear physics research. There also will be extensive facilities for materials irradiation, isotope production, and analytical chemistry. The top level work breakdown structure (WBS) for the project. As noted in this figure, one component of the project is a research and development (R&D) program (WBS 1.1). This program interfaces with all of the other project level two WBS activities. Because one of the project guidelines is to meet minimum performance goals without relying on new inventions, this R&D activity is not intended to produce new concepts to allow the project to meet minimum performance goals. Instead, the R&D program will focus on the four objectives described.

  2. The advanced neutron source research and development plan

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) is being designed as a user-oriented neutron research laboratory centered around the most intense continuous beams of thermal and subthermal neutrons in the world (an order of magnitude more intense than beams available from the most advanced existing reactors). The ANS will be built around a new research reactor of 330-MW fission power, producing an unprecedented peak thermal flux of >7 · 1019 · m-2 · s-1. Primarily a research facility, the ANS will accommodate more than 1000 academic, industrial, and government researchers each year. They will conduct basic research in all branches of science as well as applied research leading to better understanding of new materials, including high temperature super conductors, plastics, and thin films. Some 48 neutron beam stations will be set up in the ANS beam rooms and the neutron guide hall for neutron scattering and for fundamental and nuclear physics research. There also will be extensive facilities for materials irradiation, isotope production, and analytical chemistry. The top level work breakdown structure (WBS) for the project. As noted in this figure, one component of the project is a research and development (R ampersand D) program (WBS 1.1). This program interfaces with all of the other project level two WBS activities. Because one of the project guidelines is to meet minimum performance goals without relying on new inventions, this R ampersand D activity is not intended to produce new concepts to allow the project to meet minimum performance goals. Instead, the R ampersand D program will focus on the four objectives described

  3. Neutron Transfer Reactions: Surrogates for Neutron Capture for Basic and Applied Nuclear Science

    Science.gov (United States)

    Cizewski, J. A.; Jones, K. L.; Kozub, R. L.; Pain, S. D.; Peters, W. A.; Adekola, A.; Allen, J.; Bardayan, D. W.; Becker, J. A.; Blackmon, J. C.; Chae, K. Y.; Chipps, K. A.; Erikson, L.; Gaddis, A.; Harlin, C.; Hatarik, R.; Howard, J.; Jandel, M.; Johnson, M. S.; Kapler, R.; Krolas, W.; Liang, F.; Livesay, R. J.; Ma, Z.; Matei, C.; Matthews, C.; Moazen, B.; Nesaraja, C. D.; O'Malley, P.; Patterson, N.; Paulauskas, S. V.; Pelham, T.; Pittman, S. T.; Radford, D.; Rogers, J.; Schmitt, K.; Shapira, D.; Shriner, J. F.; Sissom, D. J.; Smith, M. S.; Swan, T.; Thomas, J. S.; Vieira, D. J.; Wilhelmy, J. B.; Wilson, G. L.

    2009-03-01

    Neutron capture reactions on unstable nuclei are important for both basic and applied nuclear science. A program has been developed at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory to study single-neutron transfer (d,p) reactions with rare isotope beams to provide information on neutron-induced reactions on unstable nuclei. Results from (d,p) studies on 130,132Sn, 134Te and 75As are discussed.

  4. Neutron transfer reactions: Surrogates for neutron capture for basic and applied nuclear science

    Energy Technology Data Exchange (ETDEWEB)

    Cizewski, J. A. [Rutgers University; Jones, K. L. [University of Tennessee; Kozub, R. L. [Tennessee Technological University; Pain, Steven D [ORNL; Peters, W. A. [Rutgers University; Adekola, Aderemi S [ORNL; Allen, J. [Rutgers University; Bardayan, Daniel W [ORNL; Becker, J. [Lawrence Livermore National Laboratory (LLNL); Blackmon, Jeff C [ORNL; Chae, K. Y. [University of Tennessee; Chipps, K. [Colorado School of Mines, Golden; Erikson, Luke [Colorado School of Mines, Golden; Gaddis, A. L. [Furman University; Harlin, Christopher W [ORNL; Hatarik, Robert [Rutgers University; Howard, Joshua A [ORNL; Jandel, M. [Los Alamos National Laboratory (LANL); Johnson, Micah [ORNL; Kapler, R. [University of Tennessee; Krolas, W. [University of Warsaw; Liang, J Felix [ORNL; Livesay, Jake [ORNL; Ma, Zhanwen [ORNL; Matei, Catalin [Oak Ridge Associated Universities (ORAU); Matthews, C. [Rutgers University; Moazen, Brian [University of Tennessee; Nesaraja, Caroline D [ORNL; O' Malley, Patrick [Rutgers University; Patterson, N. P. [University of Surrey, UK; Paulauskas, Stanley [University of Tennessee; Pelham, T. [University of Surrey, UK; Pittman, S. T. [University of Tennessee, Knoxville (UTK); Radford, David C [ORNL; Rogers, J. [Tennessee Technological University; Schmitt, Kyle [University of Tennessee; Shapira, Dan [ORNL; ShrinerJr., J. F. [Tennessee Technological University; Sissom, D. J. [Tennessee Technological University; Smith, Michael Scott [ORNL; Swan, T. P. [University of Surrey, UK; Thomas, J. S. [Rutgers University; Vieira, D. J. [Los Alamos National Laboratory (LANL); Wilhelmy, J. B. [Los Alamos National Laboratory (LANL); Wilson, Gemma L [ORNL

    2009-04-01

    Neutron capture reactions on unstable nuclei are important for both basic and applied nuclear science. A program has been developed at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory to study single-neutron transfer (d,p) reactions with rare isotope beams to provide information on neutron-induced reactions on unstable nuclei. Results from (d,p) studies on {sup 130,132}Sn, {sup 134}Te and {sup 75}As are discussed.

  5. Detector for advanced neutron capture experiments at LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Ullmann, J. L. (John L.); Reifarth, R. (Rene); Haight, Robert C.; Hunt, L. F. (Lloyd F.); O' Donnell, J. M.; Bredeweg, T. A. (Todd A); Wilhelmy, J. B. (Jerry B.); Fowler, Malcolm M.; Vieira, D. J. (David J.); Wouters, J. M. (Jan Marc); Strottman, D.; Kaeppeler, F. (Franz K.); Heil, M.; Chamberlin, E. P. (Edwin P.)

    2002-01-01

    The Detector for Advanced Neutron Capture Experiments (DANCE) is a 159-element 4x barium fluoride array designed to study neutron capture on small quantities, 1 mg or less, of radioactive nuclides. It is being built on a 20 m neutron flight path which views the 'upper tier' water moderator at the Manuel J. Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center. The detector design is based on Monte Carlo calculations which have suggested ways to minimize backgrounds due to neutron scattering events. A data acquisition system based on fast transient digitizers is bcing implemented

  6. The Advanced Neutron Source research and development plan

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) is being designed as a user-oriented neutron research laboratory centered around the most intense continuous beams of thermal and subthermal neutrons in the world. The ANS will be built around a new research reactor of ∼ 330 MW fission power, producing an unprecedented peak thermal flux of > 7 x 1019 M-2 · S-1. Primarily a research facility, the ANS will accommodate more than 1000 academic, industrial, and government researchers each year. They will conduct basic research in all branches of science-as well as applied research-leading to better understanding of new materials, including high temperature super conductors, plastics, and thin films. Some 48 neutron beam stations will be set up in the ANS beam rooms and the neutron guide hall for neutron scattering and for fundamental and nuclear physics research. There also will be extensive facilities for materials irradiation, isotope production, and analytical chemistry. The R ampersand D program will focus on the four objectives: Address feasibility issues; provide analysis support; evaluate options for improvement in performance beyond minimum requirements; and provide prototype demonstrations for unique facilities. The remainder of this report presents (1) the process by which the R ampersand D activities are controlled and (2) a discussion of the individual tasks that have been identified for the R ampersand D program, including their justification, schedule and costs. The activities discussed in this report will be performed by Martin Marietta Energy Systems, Inc. (MMES) through the Oak Ridge National Laboratory (ORNL) and through subcontracts with industry, universities, and other national laboratories. It should be noted that in general a success path has been assumed for all tasks

  7. A status report on the advanced neutron source project

    International Nuclear Information System (INIS)

    Design work on the Advanced Neutron Source facilities has progressed significantly, with cost saving changes to the buildings and other systems. The cold source design has advanced considerably, and in addition design work has been initiated on the hot neutron source and on a positron source. (J.P.N.)

  8. Applied research of environmental monitoring using instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Young Sam; Moon, Jong Hwa; Chung, Young Ju

    1997-08-01

    This technical report is written as a guide book for applied research of environmental monitoring using Instrumental Neutron Activation Analysis. The contents are as followings; sampling and sample preparation as a airborne particulate matter, analytical methodologies, data evaluation and interpretation, basic statistical methods of data analysis applied in environmental pollution studies. (author). 23 refs., 7 tabs., 9 figs.

  9. International Conference on Advances in Applied Mathematics

    CERN Document Server

    Hammami, Mohamed; Masmoudi, Afif

    2015-01-01

    This contributed volume presents some recent theoretical advances in mathematics and its applications in various areas of science and technology.   Written by internationally recognized scientists and researchers, the chapters in this book are based on talks given at the International Conference on Advances in Applied Mathematics (ICAAM), which took place December 16-19, 2013, in Hammamet, Tunisia.  Topics discussed at the conference included spectral theory, operator theory, optimization, numerical analysis, ordinary and partial differential equations, dynamical systems, control theory, probability, and statistics.  These proceedings aim to foster and develop further growth in all areas of applied mathematics.

  10. Advanced spallation neutron sources for condensed matter research

    International Nuclear Information System (INIS)

    Advanced spallation neutron sources afford significant advantages over existing high flux reactors. The effective flux is much greater than that currently available with reactor sources. A ten-fold increase in neutron flux will be a major benefit to a wide range of condensed matter studies, and it will realise important experiments that are marginal at reactor sources. Moreover, the high intensity of epithermal neutrons open new vistas in studies of electronic states and molecular vibrations. (author)

  11. Enhancing the detector for advanced neutron capture experiments

    International Nuclear Information System (INIS)

    The Detector for Advanced Neutron Capture Experiments (DANCE) has been used for extensive studies of neutron capture, gamma decay, photon strength functions, and prompt and delayed fission-gamma emission. Despite these successes, the potential measurements have been limited by the data acquisition hardware. We report on a major upgrade of the DANCE data acquisition that simultaneously enables strait-forward coupling to auxiliary detectors, including high-resolution high-purity germanium detectors and neutron tagging array. The upgrade will enhance the time domain accessible for time-of-flight neutron measurements as well as improve the resolution in the DANCE barium fluoride crystals for photons

  12. Advanced Neutron Source radiological design criteria

    Energy Technology Data Exchange (ETDEWEB)

    Westbrook, J.L.

    1995-08-01

    The operation of the proposed Advanced Neutron Source (ANS) facility will present a variety of radiological protection problems. Because it is desired to design and operate the ANS according to the applicable licensing standards of the Nuclear Regulatory Commission (NRC), it must be demonstrated that the ANS radiological design basis is consistent not only with state and Department of Energy (DOE) and other usual federal regulations, but also, so far as is practicable, with NRC regulations and with recommendations of such organizations as the Institute of Nuclear Power Operations (INPO) and the Electric Power Research Institute (EPRI). Also, the ANS radiological design basis is in general to be consistent with the recommendations of authoritative professional and scientific organizations, specifically the National Council on Radiation Protection and Measurements (NCRP) and the International Commission on Radiological Protection (ICRP). As regards radiological protection, the principal goals of DOE regulations and guidance are to keep occupational doses ALARA [as low as (is) reasonably achievable], given the current state of technology, costs, and operations requirements; to control and monitor contained and released radioactivity during normal operation to keep public doses and releases to the environment ALARA; and to limit doses to workers and the public during accident conditions. Meeting these general design objectives requires that principles of dose reduction and of radioactivity control by employed in the design, operation, modification, and decommissioning of the ANS. The purpose of this document is to provide basic radiological criteria for incorporating these principles into the design of the ANS. Operations, modification, and decommissioning will be covered only as they are affected by design.

  13. Advanced digital detectors for neutron imaging.

    Energy Technology Data Exchange (ETDEWEB)

    Doty, F. Patrick

    2003-12-01

    Neutron interrogation provides unique information valuable for Nonproliferation & Materials Control and other important applications including medicine, airport security, protein crystallography, and corrosion detection. Neutrons probe deep inside massive objects to detect small defects and chemical composition, even through high atomic number materials such as lead. However, current detectors are bulky gas-filled tubes or scintillator/PM tubes, which severely limit many applications. Therefore this project was undertaken to develop new semiconductor radiation detection materials to develop the first direct digital imaging detectors for neutrons. The approach relied on new discovery and characterization of new solid-state sensor materials which convert neutrons directly to electronic signals via reactions BlO(n,a)Li7 and Li6(n,a)T.

  14. DIANE: Advanced system for mobile neutron radiology

    Science.gov (United States)

    Dance, W. E.; Huriet, J. R.; Cluzeau, S.; Mast, H.-U.; Albisu, F.

    1989-04-01

    Development of a new neutron radiology system, DIANE, is underway which will provide a ten-fold improvement in image-acquisition speed over presently operating mobile systems, insuring greater inspection throughput for production applications. Based on a 10 12 n/s sealed-tube (D-T) neutron generator under development by Sodern, on LTV's neutron moderator/collimator and electronic imaging systems and on robotic and safety systems being developed by IABG and Sener, the DIANE concept is that of a complete facility for on-site neutron radiography or radioscopy. The LTV components, which provide film or electronic imaging, including digital processing of 12-bit images, have been demonstrated in three basic systems now operating with Kaman A-711 neutron generators, including one operating in IABG's facilities. Sodern has fabricated a prototype neutron generator tube, the TN 46, for emission of 10 11 n/s over 1000 to 1500 hours, at 250 kV and 2 mA in the ion beam.

  15. Multisphere system neutron spectrometry applied to dosimetry for the personnel

    International Nuclear Information System (INIS)

    Neutron dosimetry is a necessity that must be dealt with in order to ensure efficient monitoring of all personnel regarding radiology safety. Dosimetric variables are difficult to measure for they are dependent on complex functions evolving with the energy of neutrons, which forces us to determine their energetic distribution. We have chosen to use the multisphere system associated to an unfolding code in order to perform neutron spectrometry, our purpose being to determine these dosimetric variables. The initial stage consists in modifying a research code, the code SOHO, in order to adapt it to our needs. The resulting new version was subsequently tested and proven successful by means of computerized simulations. Afterwards, we used reference dosimetric and spectral beams to confirm the position results previously obtained. At the time of this test, the code SOHO yielded results coherent with the theoretical values, and even allowed the quantity of radiation diffused by the laboratory structures to be estimated. The final part of this study consists in applying the previously perfected technique to authentic situations. The results thus obtained are compared to those obtained by conventional methods in order to reveal the interest of neutron spectrometry used for dosimetry of the personnel

  16. Applied research and development of neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Yong Sam; Moon, Jong Hwa; Kim, Sun Ha; Baek, Sung Ryel; Kim, Young Gi; Jung, Hwan Sung; Park, Kwang Won; Kang, Sang Hun; Lim, Jong Myoung

    2003-05-01

    The aims of this project are to establish the quality control system of Neutron Activation Analysis(NAA) due to increase of industrial needs for standard analytical method and to prepare and identify the standard operation procedure of NAA through practical testing for different analytical items. R and D implementations of analytical quality system using neutron irradiation facility and gamma-ray measurement system and automation of NAA facility in HANARO research reactor are as following ; 1) Establishment of NAA quality control system for the maintenance of best measurement capability and the promotion of utilization of HANARO research reactor 2) Improvement of analytical sensitivity for industrial applied technologies and establishment of certified standard procedures 3) Standardization and development of Prompt Gamma-ray Activation Analysis (PGAA) technology.

  17. Applied research and development of neutron activation analysis

    International Nuclear Information System (INIS)

    The aims of this project are to establish the quality control system of Neutron Activation Analysis(NAA) due to increase of industrial needs for standard analytical method and to prepare and identify the standard operation procedure of NAA through practical testing for different analytical items. R and D implementations of analytical quality system using neutron irradiation facility and gamma-ray measurement system and automation of NAA facility in HANARO research reactor are as following ; 1) Establishment of NAA quality control system for the maintenance of best measurement capability and the promotion of utilization of HANARO research reactor 2) Improvement of analytical sensitivity for industrial applied technologies and establishment of certified standard procedures 3) Standardization and development of Prompt Gamma-ray Activation Analysis (PGAA) technology

  18. Advanced neutron instrumentation at FRM-II

    International Nuclear Information System (INIS)

    The construction of the new German high flux neutron source FRM-II is finished and FRM-II is waiting for its licence to start nuclear operation. With the beginning of the routine operation 22 instruments will be in action, including 5 irradiation facilities and 17 beam tube instruments, most of them use neutron scattering techniques. Additional instruments are under construction. Some of these instruments are unique, others are expected to be the best of their kind, all instruments are based on innovative techniques. (author)

  19. Recent advances in neutron capture therapy (NCT)

    Energy Technology Data Exchange (ETDEWEB)

    Fairchild, R.G.

    1985-01-01

    The application of the /sup 10/B(n,..cap alpha..)/sup 7/Li reaction to cancer radiotherapy (Neutron Capture therapy, or NCT) has intrigued investigators since the discovery of the neutron. This paper briefly summarizes data describing recently developed boronated compounds with evident tumor specificity and extended biological half-lives. The implication of these compounds to NCT is evaluated in terms of Therapeutic Gain (TG). The optimization of NCT using band-pass filtered beams is described, again in terms of TG, and irradiation times with these less intense beams are estimated. 24 refs., 3 figs., 3 tabs.

  20. Advances in neutron radiography at UJV

    International Nuclear Information System (INIS)

    A brief description is given of the development of neutron radiography and of planned development of neutron sources, imaging methods, evaluation methods and instrumentation. Experimental equipment and the application fields are described. The method is used in the metrology of fuel elements, for the study of the penetration of aggressive substances into building materials, for the diagnosis of bone tumors between surgeries, in archaeology, in crack detection of glued joints of honeycombed structures and in imaging the crystalline structure of castings of nickel-based superalloys. (J.P.)

  1. Enhancing the Detector for Advanced Neutron Capture Experiments

    OpenAIRE

    Couture A.; Mosby S.; Baramsai B.; Bredeweg T. A.; Jandel M.; Macon K.; O’Donnell J.M.; Rusev G.; Taddeucci T. N; Ullmann J.L.; Walker C.L.

    2015-01-01

    The Detector for Advanced Neutron Capture Experiments (DANCE) has been used for extensive studies of neutron capture, gamma decay, photon strength functions, and prompt and delayed fission-gamma emission. Despite these successes, the potential measurements have been limited by the data acquisition hardware. We report on a major upgrade of the DANCE data acquisition that simultaneously enables strait-forward coupling to auxiliary detectors, including high-resolution high-purity germanium detec...

  2. An Advanced Neutron Spectrometer for Future Manned Exploration Missions

    Science.gov (United States)

    Christl, Mark; Apple, Jeffrey A.; Cox, Mark D.; Dietz, Kurtis L.; Dobson, Christopher C.; Gibson, Brian F.; Howard, David E.; Jackson, Amanda C.; Kayatin, Mathew J.; Kuznetsov, Evgeny N.; Norwood, Joseph K.; Merril, Garrick W.; Watts, John W.; Sabra, Mohammad S.; Smith, Dennis A.; Rodriquez-Otero, Miguel A.

    2014-01-01

    An Advanced Neutron Spectrometer (ANS) is being developed to support future manned exploration missions. This new instrument uses a refined gate and capture technique that significantly improves the identification of neutrons in mixed radiation fields found in spacecraft, habitats and on planetary surfaces. The new instrument is a composite scintillator comprised of PVT loaded with litium-6 glass scintillators. We will describe the detection concept and show preliminary results from laboratory tests and exposures at particle accelerators

  3. Advanced Neutron Source (ANS) Project Progress report, FY 1991

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, J.H. (ed.) (Oak Ridge National Lab., TN (United States)); Selby, D.L.; Harrington, R.M. (Oak Ridge National Lab., TN (United States)); Thompson, P.B. (Martin Marietta Energy Systems, Inc., (United States). Engineering Division)

    1992-01-01

    This report discusses the following about the Advanced Neutron Source: Project Management; Research and Development; Fuel Development; Corrosion Loop Tests and Analyses; Thermal-Hydraulic Loop Tests; Reactor Control and Shutdown Concepts; Critical and Subcritical Experiments; Material Data, Structural Tests, and Analysis; Cold-Source Development; Beam Tube, Guide, and Instrument Development; Hot-Source Development; Neutron Transport and Shielding; I C Research and Development; Design; and Safety.

  4. Advanced Neutron Source (ANS) Project Progress report, FY 1991

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, J.H. [ed.] [Oak Ridge National Lab., TN (United States); Selby, D.L.; Harrington, R.M. [Oak Ridge National Lab., TN (United States); Thompson, P.B. [Martin Marietta Energy Systems, Inc., (United States). Engineering Division

    1992-01-01

    This report discusses the following about the Advanced Neutron Source: Project Management; Research and Development; Fuel Development; Corrosion Loop Tests and Analyses; Thermal-Hydraulic Loop Tests; Reactor Control and Shutdown Concepts; Critical and Subcritical Experiments; Material Data, Structural Tests, and Analysis; Cold-Source Development; Beam Tube, Guide, and Instrument Development; Hot-Source Development; Neutron Transport and Shielding; I & C Research and Development; Design; and Safety.

  5. Advanced Neutron Source (ANS) Project Progress report, FY 1991

    International Nuclear Information System (INIS)

    This report discusses the following about the Advanced Neutron Source: Project Management; Research and Development; Fuel Development; Corrosion Loop Tests and Analyses; Thermal-Hydraulic Loop Tests; Reactor Control and Shutdown Concepts; Critical and Subcritical Experiments; Material Data, Structural Tests, and Analysis; Cold-Source Development; Beam Tube, Guide, and Instrument Development; Hot-Source Development; Neutron Transport and Shielding; I ampersand C Research and Development; Design; and Safety

  6. Optics for Advanced Neutron Imaging and Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Moncton, David E. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Khaykovich, Boris [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2016-03-30

    During the report period, we continued the work as outlined in the original proposal. We have analyzed potential optical designs of Wolter mirrors for the neutron-imaging instrument VENUS, which is under construction at SNS. In parallel, we have conducted the initial polarized imaging experiment at Helmholtz Zentrum, Berlin, one of very few of currently available polarized-imaging facilities worldwide.

  7. Simulation of a modified neutron detector applied in CSNS

    Institute of Scientific and Technical Information of China (English)

    MA Zhong-Jian; WANG Qing-Bin; WU Qing-Biao

    2009-01-01

    We simulate the response of a modified Anderson-Braun rem counter in the energy range from thermal energy to about 10 GeV using the FLUKA code.Also,we simulate the lethargy spectrum of CSNS outside the beam dump.Traditional BFs tube is replaced by the 3He tube,a layer of 0.6 cm lead is added outside the boron doped plastic attenuator and a sphere configuration is adopted.The simulation result shows that its response is exactly fit to H*(10) in the neutron energies between 10 keV and approximately 1 GeV,although the monitor slightly underestimates H*(10) in the energy range from thermal energy to about 10 keV.According to the characteristics of the CSNS,this modified counter increases the neutron energy response by 30% compared with the traditional monitors,and it can be applied in other kinds of stray field rich of high energy neutrons.

  8. Advanced neutron diagnostics for the Nova laser facility

    International Nuclear Information System (INIS)

    The authors report on recent work addressing advanced neutron diagnostics to be implemented on the Nova laser facility. The goals of these instruments are to measure the following properties of laser fusion targets: compressed fuel areal-density (Rho-R), time-duration, and spatial extent of the neutron emission. The authors will discuss the use of a noval time-of-flight system, radiochemical techniques, and the use of plastic track detectors to measure the compressed Rho-R. The authors will present the design of two proposed instruments to measure the burn time; one uses a sandwich of thin layers of plastic scintillator and uranium coupled to a streak camera while the other design makes use of a neutron sensitive transmission line. Finally, the authors will discuss methods capable of obtaining neutron images of the compressed pellet core

  9. Inelastic neutron scattering applied to materials for energy

    Directory of Open Access Journals (Sweden)

    Piovano Andrea

    2015-01-01

    Full Text Available Inelastic neutron scattering measures the dynamical processes in materials, i.e. the spontaneous fluctuations that experiences samples when interacting with neutrons. An inelastic neutronspectrum is obtained from measurements of both energy and the momentum transfer between the neutron and the sample. This short dissertation explains fundamental concepts of the inelastic neutron scattering process, describes instrumentation, and gives a couple of materials applications were inelastic neutron scattering has been proven to be useful like ionic conductors and thermoelectric materials.

  10. Inelastic neutron scattering applied to materials for energy

    OpenAIRE

    Piovano Andrea

    2015-01-01

    Inelastic neutron scattering measures the dynamical processes in materials, i.e. the spontaneous fluctuations that experiences samples when interacting with neutrons. An inelastic neutronspectrum is obtained from measurements of both energy and the momentum transfer between the neutron and the sample. This short dissertation explains fundamental concepts of the inelastic neutron scattering process, describes instrumentation, and gives a couple of materials applications were inelastic neutron ...

  11. BNL Activities in Advanced Neutron Source Development: Past and Present

    Energy Technology Data Exchange (ETDEWEB)

    Hastings, J.B.; Ludewig, H.; Montanez, P.; Todosow, M.; Smith, G.C.; Larese, J.Z.

    1998-06-14

    Brookhaven National Laboratory has been involved in advanced neutron sources almost from its inception in 1947. These efforts have mainly focused on steady state reactors beginning with the construction of the first research reactor for neutron beams, the Brookhaven Graphite Research Reactor. This was followed by the High Flux Beam Reactor that has served as the design standard for all the subsequent high flux reactors constructed worldwide. In parallel with the reactor developments BNL has focused on the construction and use of high energy proton accelerators. The first machine to operate over 1 GeV in the world was the Cosmotron. The machine that followed this, the AGS, is still operating and is the highest intensity proton machine in the world and has nucleated an international collaboration investigating liquid metal targets for next generation pulsed spallation sources. Early work using the Cosmotron focused on spallation product studies for both light and heavy elements into the several GeV proton energy region. These original studies are still important today. In this report we discuss the facilities and activities at BNL focused on advanced neutron sources. BNL is involved in the proton source for the Spallation Neutron source, spectrometer development at LANSCE, target studies using the AGS and state-of-the-art neutron detector development.

  12. BNL ACTIVITIES IN ADVANCED NEUTRON SOURCE DEVELOPMENT: PAST AND PRESENT

    Energy Technology Data Exchange (ETDEWEB)

    HASTINGS,J.B.; LUDEWIG,H.; MONTANEZ,P.; TODOSOW,M.; SMITH,G.C.; LARESE,J.Z.

    1998-06-14

    Brookhaven National Laboratory has been involved in advanced neutron sources almost from its inception in 1947. These efforts have mainly focused on steady state reactors beginning with the construction of the first research reactor for neutron beams, the Brookhaven Graphite Research Reactor. This was followed by the High Flux Beam Reactor that has served as the design standard for all the subsequent high flux reactors constructed worldwide. In parallel with the reactor developments BNL has focused on the construction and use of high energy proton accelerators. The first machine to operate over 1 GeV in the world was the Cosmotron. The machine that followed this, the AGS, is still operating and is the highest intensity proton machine in the world and has nucleated an international collaboration investigating liquid metal targets for next generation pulsed spallation sources. Early work using the Cosmotron focused on spallation product studies for both light and heavy elements into the several GeV proton energy region. These original studies are still important today. In the sections below the authors discuss the facilities and activities at BNL focused on advanced neutron sources. BNL is involved in the proton source for the Spallation Neutron source, spectrometer development at LANSCE, target studies using the AGS and state-of-the-art neutron detector development.

  13. Neutronic challenges of advanced boiling water reactor designs

    International Nuclear Information System (INIS)

    The advancement of Boiling Water Reactor technology has been under investigation at the Center for Advance Nuclear Energy Systems at MIT. The advanced concepts under study provide economic incentives through enabling further power uprates (i.e. increasing vessel power density) or better fuel cycle uranium utilization. The challenges in modeling of three advanced concepts with focus on neutronics are presented. First, the Helical Cruciform Fuel rod has been used in some Russian reactors, and studied at MIT for uprating the power in LWRs through increased heat transfer area per unit core volume. The HCF design requires high fidelity 3D tools to assess its reactor physics behavior as well as thermal and fuel performance. Second, an advanced core design, the BWR-HD, was found to promise 65% higher power density over existing BWRs, while using current licensing tools and existing technology. Its larger assembly size requires stronger coupling between neutronics and thermal hydraulics compared to the current practice. Third is the reduced moderation BWRs, which had been proposed in Japan to enable breeding and burning of fuel as an alternative to sodium fast reactors. Such technology suffers from stronger sensitivity of its neutronics to the void fraction than the traditional BWRs, thus requiring exact modeling of the core conditions such as bypass voiding, to correctly characterize its performance. (author)

  14. Applied research and development of neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Yong Sam; Moon, Jong Hwa; Kim, Sun Ha; Bak, Sung Ryel; Park, Yong Chul; Kim, Young Ki; Chung, Hwan Sung; Park, Kwang Won; Kang, Sang Hun

    2000-05-01

    This report is written for results of research and development as follows : improvement of neutron irradiation facilities, counting system and development of automation system and capsules for NAA in HANARO ; improvement of analytical procedures and establishment of analytical quality control and assurance system; applied research and development of environment, industry and human health and its standardization. For identification and standardization of analytical method, environmental biological samples and polymer are analyzed and uncertainity of measurement are estimated. Also data intercomparison and proficency test were performed. Using airborne particulate matter chosen as a environmental indicators, trace elemental concentrations of sample collected at urban and rural site are determined and then the calculation of statistics and the factor analysis are carried out for investigation of emission source. International cooperation research project was carried out for utilization of nuclear techniques.

  15. Assessment of the roles of the Advanced Neutron Source Operators

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) is unique in the extent to which human factors engineering (HFE) principles are being applied at the conceptual design stage. initial HFE accomplishments include the development of an ANS HFE program plan, operating philosophy, and functional analysis. In FY 1994, HFE activities focused on the role of the ANS control room reactor operator (RO). An operator-centered control room model was used in conjunction with information gathered from existing ANS system design descriptions and other literature to define a list of RO responsibilities. From this list, a survey instrument was developed and administered to ANS design engineers, operations management personnel at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR), and HFIR ROs to detail the nature of the RO position. Initial results indicated that the RO will function as a high-level system supervisor with considerable monitoring, verification, and communication responsibilities. The relatively high level of control automation has resulted in a reshaping of the RO's traditional safety and investment protection roles

  16. Advanced Neutron Source Reactor zoning, shielding, and radiological optimization guide

    International Nuclear Information System (INIS)

    In the design of major nuclear facilities, it is important to protect both humans and equipment excessive radiation dose. Past experience has shown that it is very effective to apply dose reduction principles early in the design of a nuclear facility both to specific design features and to the manner of operation of the facility, where they can aid in making the facility more efficient and cost-effective. Since the appropriate choice of radiological controls and practices varies according to the case, each area of the facility must be analyzed for its radiological impact, both by itself and in interactions with other areas. For the Advanced Neutron Source (ANS) project, a large relational database will be used to collect facility information by system and relate it to areas. The database will also hold the facility dose and shielding information as it is produced during the design process. This report details how the ANS zoning scheme was established and how the calculation of doses and shielding are to be done

  17. Review of the Advanced Neutron Source (ANS) materials irradiation facilities

    International Nuclear Information System (INIS)

    The purpose of the workshop was to document as accurately as possible the present and future needs for neutron irradiation capacity and facilities as related to the design of the Advanced Neutron Source (ANS) which will be the next generation steady-state research reactor. The report provides the findings and recommendations of the working group. After introductory and background information is presented, the discussion includes the status of the ANS design, in particular in-core materials irradiation facilities design and important experimental parameters. The summary of workshop discussions describes a survey of irradiation-effects research community and opportunities for ex-core irradiation facilities. 20 refs., 2 figs., 4 tabs

  18. Scientific opportunities with advanced facilities for neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Lander, G.H.; Emery, V.J. (eds.)

    1984-01-01

    The present report documents deliberations of a large group of experts in neutron scattering and fundamental physics on the need for new neutron sources of greater intensity and more sophisticated instrumentation than those currently available. An additional aspect of the Workshop was a comparison between steady-state (reactor) and pulsed (spallation) sources. The main conclusions were: (1) the case for a new higher flux neutron source is extremely strong and such a facility will lead to qualitatively new advances in condensed matter science and fundamental physics; (2) to a large extent the future needs of the scientific community could be met with either a 5 x 10/sup 15/ n cm/sup -2/s/sup -1/ steady state source or a 10/sup 17/ n cm/sup -2/s/sup -1/ peak flux spallation source; and (3) the findings of this Workshop are consistent with the recommendations of the Major Materials Facilities Committee.

  19. New features in cold neutron radiography and tomography Part II: applied energy-selective neutron radiography and tomography

    International Nuclear Information System (INIS)

    The neutron attenuation coefficient drops for many solid materials quite drastically at a defined cold neutron energy known as a Bragg-cut-off in the cross-section diagrams. In many cases, the drop in attenuation for the corresponding elements is significant and this behavior can be exploited to change the material contrast in radiography and tomography images by modifying the spectrum of the applied neutron beam. The energy-dependent experiments were performed at the Prompt Gamma-ray Activation beam line where the irradiation position is at the end of a curved neutron guide, which delivers cold neutrons from the spallation source SINQ (PSI, Switzerland). This beam position gave the opportunity to perform radiography and tomography at low neutron energies. An effective monochromatization of the primary neutron beam was obtained by using a neutron velocity selector. The intensity of the modified beam was still reasonable for radiography images at different neutron energies and the experiments were performed in relatively short measuring times. A variety of samples were studied to illustrate possible applications of energy-selective radiography and tomography. This new neutron imaging technique provided encouraging results and projects of developing permanent facilities for such investigations at PSI and FRM II are under study

  20. Advanced Neutron Source: Plant Design Requirements. Revision 4

    Energy Technology Data Exchange (ETDEWEB)

    1990-07-01

    The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS.

  1. Recent Advances in Nanotechnology Applied to Biosensors

    Directory of Open Access Journals (Sweden)

    Daxiang Cui

    2009-02-01

    Full Text Available In recent years there has been great progress the application of nanomaterials in biosensors. The importance of these to the fundamental development of biosensors has been recognized. In particular, nanomaterials such as gold nanoparticles, carbon nanotubes, magnetic nanoparticles and quantum dots have been being actively investigated for their applications in biosensors, which have become a new interdisciplinary frontier between biological detection and material science. Here we review some of the main advances in this field over the past few years, explore the application prospects, and discuss the issues, approaches, and challenges, with the aim of stimulating a broader interest in developing nanomaterial-based biosensors and improving their applications in disease diagnosis and food safety examination.

  2. Conceptual study of advanced PWR core design. Development of advanced PWR core neutronics analysis system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Hyo; Kim, Seung Cho; Kim, Taek Kyum; Cho, Jin Young; Lee, Hyun Cheol; Lee, Jung Hun; Jung, Gu Young [Seoul National University, Seoul (Korea, Republic of)

    1995-08-01

    The neutronics design system of the advanced PWR consists of (i) hexagonal cell and fuel assembly code for generation of homogenized few-group cross sections and (ii) global core neutronics analysis code for computations of steady-state pin-wise or assembly-wise core power distribution, core reactivity with fuel burnup, control rod worth and reactivity coefficients, transient core power, etc.. The major research target of the first year is to establish the numerical method and solution of multi-group diffusion equations for neutronics code development. Specifically, the following studies are planned; (i) Formulation of various numerical methods such as finite element method(FEM), analytical nodal method(ANM), analytic function expansion nodal(AFEN) method, polynomial expansion nodal(PEN) method that can be applicable for the hexagonal core geometry. (ii) Comparative evaluation of the numerical effectiveness of these methods based on numerical solutions to various hexagonal core neutronics benchmark problems. Results are follows: (i) Formulation of numerical solutions to multi-group diffusion equations based on numerical methods. (ii) Numerical computations by above methods for the hexagonal neutronics benchmark problems such as -VVER-1000 Problem Without Reflector -VVER-440 Problem I With Reflector -Modified IAEA PWR Problem Without Reflector -Modified IAEA PWR Problem With Reflector -ANL Large Heavy Water Reactor Problem -Small HTGR Problem -VVER-440 Problem II With Reactor (iii) Comparative evaluation on the numerical effectiveness of various numerical methods. (iv) Development of HEXFEM code, a multi-dimensional hexagonal core neutronics analysis code based on FEM. In the target year of this research, the spatial neutronics analysis code for hexagonal core geometry(called NEMSNAP-H temporarily) will be completed. Combination of NEMSNAP-H with hexagonal cell and assembly code will then equip us with hexagonal core neutronics design system. (Abstract Truncated)

  3. Validation of multigroup neutron cross sections for the Advanced Neutron Source against the FOEHN critical experimental measurements

    International Nuclear Information System (INIS)

    The FOEHN critical experiments were analyzed to validate the use of multigroup cross sections in the design of the Advanced Neutron Source. Eleven critical configurations were evaluated using the KENO, DORT, and VENTURE neutronics codes. Eigenvalue and power density profiles were computed and show very good agreement with measured values

  4. High resolution neutron tomography applied to tooth fillings on real teeth by use of neutron lens

    International Nuclear Information System (INIS)

    Today tomography is a well known technique for nondestructive analysis of samples. By taking several X-ray pictures from an object, it is possible to make a 3D reconstruction. The same thing can be done with neutrons. Since very recent it is possible to produce a high-flux neutron beam. By looking at the attenuation of the neutron beam in the sample from different angles, it is possible to make a neutron tomography. The properties of neutrons are so much different from X-rays that a new era in tomography has started. Where X-rays have a hard time penetrating samples containing heavy elements (Pb, Bi, U, Hg, Au), neutrons just seem to walk through. But when the neutrons encounter samples containing light compounds like water, oil, paper, B, Li,... they are easily absorbed. This makes the use of neutrons for imaging complementary to the well known X-ray imaging. The most used tooth filling material nowadays is amalgam. Amalgam is a mixture of different metals, like silver, tin, copper, mercury. Mercury is dangerous for the human body when it enters the blood stream. These fillings are very dense and X-rays have a very hard time penetrating it. Neutrons are the ideal probe for investigation of these high density regions. The result of the tomography reveals information on the long term stability of amalgam fillings and could help the still ongoing debate on the safety of the fillings. (author)

  5. Study of the RP-10 reactor neutron beam applied to the neutron radiography

    International Nuclear Information System (INIS)

    We have studied the RP-10 reactor radial neutron beam No. 3, which is used for neutron radiographies, by comparing radiograph's with and without the inner duct, and neutron flux determination with in flakes along the external duct, being the presence of photons creating signals at comparable levels of neutron effects, which reduce the quality of the analysis, values around 106 and 104 n/cm2s for thermal and epithermal flux were obtained respectively. It is recommended evaluate the design of the internal duct which presents strong photon emission. (authors).

  6. Advanced Neutron Source (ANS) Project progress report, FY 1994

    International Nuclear Information System (INIS)

    The President's budget request for FY 1994 included a construction project for the Advanced Neutron Source (ANS). However, the budget that emerged from the Congress did not, and so activities during this reporting period were limited to continued research and development and to advanced conceptual design. A significant effort was devoted to a study, requested by the US Department of Energy (DOE) and led by Brookhaven National Laboratory, of the performance and cost impacts of reducing the uranium fuel enrichment below the baseline design value of 93%. The study also considered alternative core designs that might mitigate those impacts. The ANS Project proposed a modified core design, with three fuel elements instead of two, that would allow operation with only 50% enriched uranium and use existing fuel technology. The performance penalty would be 15--20% loss of thermal neutron flux; the flux would still just meet the minimum design requirement set by the user community. At the time of this writing, DOE has not established an enrichment level for ANS, but two advisory committees have recommended adopting the new core design, provided the minimum flux requirements are still met

  7. Advanced Neutron Source (ANS) Project progress report, FY 1994

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, J.H.; King-Jones, K.H. [eds.; Selby, D.L.; Harrington, R.M. [Oak Ridge National Lab., TN (United States); Thompson, P.B. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States). Central Engineering Services

    1995-01-01

    The President`s budget request for FY 1994 included a construction project for the Advanced Neutron Source (ANS). However, the budget that emerged from the Congress did not, and so activities during this reporting period were limited to continued research and development and to advanced conceptual design. A significant effort was devoted to a study, requested by the US Department of Energy (DOE) and led by Brookhaven National Laboratory, of the performance and cost impacts of reducing the uranium fuel enrichment below the baseline design value of 93%. The study also considered alternative core designs that might mitigate those impacts. The ANS Project proposed a modified core design, with three fuel elements instead of two, that would allow operation with only 50% enriched uranium and use existing fuel technology. The performance penalty would be 15--20% loss of thermal neutron flux; the flux would still just meet the minimum design requirement set by the user community. At the time of this writing, DOE has not established an enrichment level for ANS, but two advisory committees have recommended adopting the new core design, provided the minimum flux requirements are still met.

  8. Gamma/neutron dose evaluation using Fricke gel and alanine gel dosimeters to be applied in boron neutron capture therapy

    International Nuclear Information System (INIS)

    Full text: Radiosurgery is a non-invasive surgery carried out by means of directed beams of ionizing radiation. This procedure was developed since there are many diseases for which conventional surgical treatment can not be applied, due to difficult or vital structures being damaged. Neutron radiation from nuclear reactors is used in a kind of radiosurgery called Boron Neutron Capture Therapy (BNCT) for the treatment of brain tumours which depends on the interaction of slow neutrons with 10B isotope injected in the tumour to produce alpha particles. Gel Dosimetry allows three-dimensional (3D) measurement of absorbed dose in tissueequivalent dosimeter phantoms. The measure technique is based on the transformation of ferrous ions (Fe2+) and ferric ions (Fe3+). The ferric ions concentration can be measured by spectrophotometry technique comparing the two wavelengths, 457 nm band that corresponds to ferrous ions concentration and 588 nm band that corresponds to ferric ions concentration. This work aims to study the gamma/neutron reactor dose relationship to be applied in BNCT using gel dosimeters. The Fricke Xylenol Gel (FXG) and Alanine Gel (AG) gel solutions produced at IPEN using gelatine 300 bloom were mixed with Na2B4O7 salt containing 19,9% of 10B isotope. This solutions were used to evaluate thermal and epithermal neutrons and gamma doses at an irradiation cell on BH3 of the IEA-R1 research reactor of IPEN

  9. Review of neutronic assessments applied to small reactor core physics

    International Nuclear Information System (INIS)

    In its design division for material test reactors and research reactors, AREVA TA has to characterize these manufactured cores. This step is sequential with neutronics benchmarks associated with validation (standard Verification and Validation approach). The previous two points are embedded in core projects and can be run separately especially when experimental tests are foreseen for validation database enrichment. Methodological standard is given in order to match validation and benchmark process illustrated alongside with two specific items on critical research reactors (AZUR - JHR) and subcritical mock up (AZUR). (author)

  10. Phase 1 environmental report for the Advanced Neutron Source at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Blasing, T.J.; Brown, R.A.; Cada, G.F.; Easterly, C.; Feldman, D.L.; Hagan, C.W.; Harrington, R.M.; Johnson, R.O.; Ketelle, R.H.; Kroodsma, R.L.; McCold, L.N.; Reich, W.J.; Scofield, P.A.; Socolof, M.L.; Taleyarkhan, R.P.; Van Dyke, J.W.

    1992-02-01

    The US Department of Energy (DOE) has proposed the construction and operation of the Advanced Neutron Source (ANS), a 330-MW(f) reactor, at Oak Ridge National Laboratory (ORNL) to support neutron scattering and nuclear physics experiments. ANS would provide a steady-state source of neutrons that are thermalized to produce sources of hot, cold, and very coal neutrons. The use of these neutrons in ANS experiment facilities would be an essential component of national research efforts in basic materials science. Additionally, ANS capabilities would include production of transplutonium isotopes, irradiation of potential fusion and fission reactor materials, activation analysis, and production of medical and industrial isotopes such as {sup 252}Cf. Although ANS would not require licensing by the US Nuclear Regulatory Commission (NRC), DOE regards the design, construction, and operation of ANS as activities that would produce a licensable facility; that is, DOE is following the regulatory guidelines that NRC would apply if NRC were licensing the facility. Those guidelines include instructions for the preparation of an environmental report (ER), a compilation of available data and preliminary analyses regarding the environmental impacts of nuclear facility construction and operation. The ER, described and outlined in NRC Regulatory Guide 4.2, serves as a background document to facilitate the preparation of environmental impact statements (EISs). Using Regulatory Guide 4.2 as a model, this ANS ER provides analyses and information specific to the ANS site and area that can be adopted (and modified, if necessary) for the ANS EIS. The ER is being prepared in two phases. Phase 1 ER includes many of the data and analyses needed to prepare the EIS but does not include data or analyses of alternate sites or alternate technologies. Phase 2 ER will include the additional data and analyses stipulated by Regulatory Guide 4.2.

  11. Phase 1 environmental report for the Advanced Neutron Source at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) has proposed the construction and operation of the Advanced Neutron Source (ANS), a 330-MW(f) reactor, at Oak Ridge National Laboratory (ORNL) to support neutron scattering and nuclear physics experiments. ANS would provide a steady-state source of neutrons that are thermalized to produce sources of hot, cold, and very coal neutrons. The use of these neutrons in ANS experiment facilities would be an essential component of national research efforts in basic materials science. Additionally, ANS capabilities would include production of transplutonium isotopes, irradiation of potential fusion and fission reactor materials, activation analysis, and production of medical and industrial isotopes such as 252Cf. Although ANS would not require licensing by the US Nuclear Regulatory Commission (NRC), DOE regards the design, construction, and operation of ANS as activities that would produce a licensable facility; that is, DOE is following the regulatory guidelines that NRC would apply if NRC were licensing the facility. Those guidelines include instructions for the preparation of an environmental report (ER), a compilation of available data and preliminary analyses regarding the environmental impacts of nuclear facility construction and operation. The ER, described and outlined in NRC Regulatory Guide 4.2, serves as a background document to facilitate the preparation of environmental impact statements (EISs). Using Regulatory Guide 4.2 as a model, this ANS ER provides analyses and information specific to the ANS site and area that can be adopted (and modified, if necessary) for the ANS EIS. The ER is being prepared in two phases. Phase 1 ER includes many of the data and analyses needed to prepare the EIS but does not include data or analyses of alternate sites or alternate technologies. Phase 2 ER will include the additional data and analyses stipulated by Regulatory Guide 4.2

  12. Dosimetric evaluation of neutron capture therapy for local advanced breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yanagie, H. [Department of Nuclear Engineering and Management, Graduate School of Engineering, University of Tokyo, Tokyo (Japan); Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan)], E-mail: yanagie@n.t.u-tokyo.ac.jp; Kumada, H. [Japan Atomic Research Institute, Ibaraki (Japan); Sakurai, Y. [Research Reactor Institute, Kyoto University, Osaka (Japan); Nakamura, T. [Japan Atomic Research Institute, Ibaraki (Japan); Department of Nuclear Physics, Ibaraki University, Ibaraki (Japan); Furuya, Y. [Department of Surgery, Satukidai Hospital, Chiba (Japan); Sugiyama, H. [Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan); Ono, K. [Research Reactor Institute, Kyoto University, Osaka (Japan); Takamoto, S. [Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan); Department of Cardiac Surgery, University of Tokyo Hospital, Tokyo (Japan); Eriguchi, M. [Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan); Department of Microbiology, Syowa University School of Pharmaceutical Sciences, Tokyo (Japan); Takahashi, H. [Department of Nuclear Engineering and Management, Graduate School of Engineering, University of Tokyo, Tokyo (Japan); Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan)

    2009-07-15

    Local recurrence breast cancer is one of the most difficult conditions to cure and there is a need for new therapy. If sufficient boron compound can be targeted to the tumor, boron neutron capture therapy (BNCT) can be applied to local recurrent breast cancer. In this study, we performed a preliminary dosimetry with a phantom model of the mammary gland at Kyoto University Research Reactor (KUR), and a feasibility dosimetry with JAERI Computational Dosimetry System (JCDS) at JRR4 reactor of Japan Atomic Research Institute. We performed preliminary dosimetry of a phantom model of the mammary gland with thermal neutron irradiation (OO-0011 mode) on LiF collimation at KUR. The thermal neutron flux was 5.16 E+08 cm{sup -2} s{sup -1} at the surface of phantom. The blood boron concentration is estimated to be 30 ppm; tumor boron concentration is also estimated to be 90 ppm according to tumor/blood ratio 3 and skin/blood ratio 1.2. Tumor RBE dose is estimated to be 47 Gy/h, and skin RBE dose is 12.4 Gy/h. In case of advanced breast cancer, we performed the feasibility estimation of 3D construction of tumor according to the MRI imaging of a patient with epithermal neutron mode at JRR4. The blood boron concentration (ppm) and tumor/normal tissue ratio are estimated to be 24 and 3.5, respectively. Skin RBE dose is restricted to 10 Gy/h, the maximum tumor RBE dose, minimum tumor RBE dose, and mean tumor RBE dose are 42.2, 11.3, and 28.9 Gy-Eq, respectively, in half hour irradiation. In this study, we showed the possibility to apply BNCT to local recurrent breast cancer. We can irradiate tumors selectively and as safely as possible, reducing the effects on neighboring healthy tissues.

  13. Advanced thermal-hydraulic and neutronic codes: current and future applications. Summary and conclusions

    International Nuclear Information System (INIS)

    An OECD Workshop on Advanced Thermal-Hydraulic and Neutronic Codes Applications was held from 10 to 13 April 2000, in Barcelona, Spain, sponsored by the Committee on the Safety of Nuclear Installations (CSNI) of the OECD Nuclear Energy Agency (NEA). It was organised in collaboration with the Spanish Nuclear Safety Council (CSN) and hosted by CSN and the Polytechnic University of Catalonia (UPC) in collaboration with the Spanish Electricity Association (UNESA). The objectives of the Workshop were to review the developments since the previous CSNI Workshop held in Annapolis [NEA/CSNI/ R(97)4; NUREG/CP-0159], to analyse the present status of maturity and remnant needs of thermal-hydraulic (TH) and neutronic system codes and methods, and finally to evaluate the role of these tools in the evolving regulatory environment. The Technical Sessions and Discussion Sessions covered the following topics: - Regulatory requirements for Best-Estimate (BE) code assessment; - Application of TH and neutronic codes for current safety issues; - Uncertainty analysis; - Needs for integral plant transient and accident analysis; - Simulators and fast running codes; - Advances in next generation TH and neutronic codes; - Future trends in physical modeling; - Long term plans for development of advanced codes. The focus of the Workshop was on system codes. An incursion was made, however, in the new field of applying Computational Fluid Dynamic (CFD) codes to nuclear safety analysis. As a general conclusion, the Barcelona Workshop can be considered representative of the progress towards the targets marked at Annapolis almost four years ago. The Annapolis Workshop had identified areas where further development and specific improvements were needed, among them: multi-field models, transport of interfacial area, 2D and 3D thermal-hydraulics, 3-D neutronics consistent with level of details of thermal-hydraulics. Recommendations issued at Annapolis included: developing small pilot/test codes for

  14. Proceedings of the workshop on advanced thermal-hydraulic and neutronic codes: current and future applications

    International Nuclear Information System (INIS)

    An OECD Workshop on Advanced Thermal-Hydraulic and Neutronic Codes Applications was held from 10 to 13 April 2000, in Barcelona, Spain, sponsored by the Committee on the Safety of Nuclear Installations (CSNI) of the OECD Nuclear Energy Agency (NEA). It was organised in collaboration with the Spanish Nuclear Safety Council (CSN) and hosted by CSN and the Polytechnic University of Catalonia (UPC) in collaboration with the Spanish Electricity Association (UNESA). The objectives of the Workshop were to review the developments since the previous CSNI Workshop held in Annapolis [NEA/CSNI/ R(97)4; NUREG/CP-0159], to analyse the present status of maturity and remnant needs of thermal-hydraulic (TH) and neutronic system codes and methods, and finally to evaluate the role of these tools in the evolving regulatory environment. The Technical Sessions and Discussion Sessions covered the following topics: - Regulatory requirements for Best-Estimate (BE) code assessment; - Application of TH and neutronic codes for current safety issues; - Uncertainty analysis; - Needs for integral plant transient and accident analysis; - Simulators and fast running codes; - Advances in next generation TH and neutronic codes; - Future trends in physical modeling; - Long term plans for development of advanced codes. The focus of the Workshop was on system codes. An incursion was made, however, in the new field of applying Computational Fluid Dynamic (CFD) codes to nuclear safety analysis. As a general conclusion, the Barcelona Workshop can be considered representative of the progress towards the targets marked at Annapolis almost four years ago. The Annapolis Workshop had identified areas where further development and specific improvements were needed, among them: multi-field models, transport of interfacial area, 2D and 3D thermal-hydraulics, 3-D neutronics consistent with level of details of thermal-hydraulics. Recommendations issued at Annapolis included: developing small pilot/test codes for

  15. Proceedings of the fifteenth meeting of the international collaboration on advanced neutron sources (ICANS-XV). Advanced neutron sources towards the next century

    International Nuclear Information System (INIS)

    The fifteenth meeting of the International Collaboration on Advanced Neutron Sources (ICANS-XV) was held at Epocal Tsukuba, International Congress Center on 6-9 November 2000. It was hosted by Japan Atomic Energy Research Institute (JAERI) and High Energy Accelerator Research Organization (KEK). This meeting focused on 'Neutron Sources toward the 21st Century' and research activities related to targets and moderators, neutron scattering instruments and accelerators were presented. The 151 of the presented papers are indexed individually. (J.P.N.)

  16. Proceedings of the fifteenth meeting of the international collaboration on advanced neutron sources (ICANS-XV). Advanced neutron sources towards the next century

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Jun-ichi [Center for Neutron Science, Tokai Research Establishment, Japan Atomic Energy Research Institute, Tokai, Ibaraki (Japan); Itoh, Shinichi [Neutron Science Laboratory, High Energy Accelerator Research Organization, Tsukuba, Ibaraki (JP)] (eds.)

    2001-03-01

    The fifteenth meeting of the International Collaboration on Advanced Neutron Sources (ICANS-XV) was held at Epocal Tsukuba, International Congress Center on 6-9 November 2000. It was hosted by Japan Atomic Energy Research Institute (JAERI) and High Energy Accelerator Research Organization (KEK). This meeting focused on 'Neutron Sources toward the 21st Century' and research activities related to targets and moderators, neutron scattering instruments and accelerators were presented. The 151 of the presented papers are indexed individually. (J.P.N.)

  17. Evaluation of energy response of neutron rem monitor applied to high-energy accelerator facilities

    Energy Technology Data Exchange (ETDEWEB)

    Nakane, Yoshihiro; Harada, Yasunori; Sakamoto, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    2003-03-01

    A neutron rem monitor was newly developed for applying to the high-intensity proton accelerator facility (J-PARC) that is under construction as a joint project between the Japan Atomic Energy Research Institute and the High Energy Accelerator Research Organization. To measure the dose rate accurately for wide energy range of neutrons from thermal to high-energy region, the neutron rem monitor was fabricated by adding a lead breeder layer to a conventional neutron rem monitor. The energy response of the monitor was evaluated by using neutron transport calculations for the energy range from thermal to 150 MeV. For verifying the results, the response was measured at neutron fields for the energy range from thermal to 65 MeV. The comparisons between the energy response and dose conversion coefficients show that the newly developed neutron rem monitor has a good performance in energy response up to 150 MeV, suggesting that the present study offered prospects of a practical fabrication of the rem monitor applicable to the high intensity proton accelerator facility. (author)

  18. Advanced neutron source final preconceptual reference core design

    International Nuclear Information System (INIS)

    The preconceptual design phase of the Advanced Neutron Source (ANS) Project ended with the selection of a reference reactor core that will be used to begin conceptual design work. The new reference core consists of two involute fuel elements, of different diameters, aligned axially with a small axial gap between them. The use of different element diameters permits a separate flow of coolant to be provided for each one, thus enhancing the heat removal capability and increasing the thermal-hydraulic margins. The improved cooling allows the elements to be relatively long and thin, so self-shielding is reduced and an acceptable core life can be achieved with a relatively small loading of highly enriched uranium silicide fuel clad in aluminium. The new reference design has a fueled volume 67.4 L, each element having a heated length of 474 mm and a radial fuel thickness of 66 mm. The end-of-cycle peak thermal flux in the large heavy-water reflector tank around the core is estimated to be in the range of 0.8 to 1.0 x 1020 m-2 · s-1. 7 refs., 23 figs., 15 tabs

  19. Advanced neutron source design: burnout heat flux correlation development

    International Nuclear Information System (INIS)

    In the advanced neutron source reactor (ANSR) fuel element region, heat fluxes will be elevated. Early designs corresponded to average and estimated hot-spot fluxes of 11 to 12 and 21 to 22 MW/m2, respectively. Design changes under consideration may lower these values to ∼ 9 and 17 MW/m1. In either event, the development of a satisfactory burnout heat flux correlation is an important element among the many thermal-hydraulic design issues, since the critical power ratio will depend in part on its validity. Relatively little work in the area of subcooled-flow burnout has been published over the past 12 yr. The authors have compared seven burnout correlations and modifications therefore with several sets of experimental data, of which the most relevant to the ANS core are those referenced. The best overall agreement between the correlations tested and these data is currently provided by a modification of Thorgerson et al. correlation. The variable ranges of the experimental data are outlined and the results of the correlation comparisons are summarized

  20. Neutron tomography of particulate filters: a non-destructive investigation tool for applied and industrial research

    International Nuclear Information System (INIS)

    This research describes the development and implementation of high-fidelity neutron imaging and the associated analysis of the images. This advanced capability allows the non-destructive, non-invasive imaging of particulate filters (PFs) and how the deposition of particulate and catalytic washcoat occurs within the filter. The majority of the efforts described here were performed at the High Flux Isotope Reactor (HFIR) CG-1D neutron imaging beamline at Oak Ridge National Laboratory; the current spatial resolution is approximately 50 μm. The sample holder is equipped with a high-precision rotation stage that allows 3D imaging (i.e., computed tomography) of the sample when combined with computerized reconstruction tools. What enables the neutron-based image is the ability of some elements to absorb or scatter neutrons where other elements allow the neutron to pass through them with negligible interaction. Of particular interest in this study is the scattering of neutrons by hydrogen-containing molecules, such as hydrocarbons (HCs) and/or water, which are adsorbed to the surface of soot, ash and catalytic washcoat. Even so, the interactions with this adsorbed water/HC is low and computational techniques were required to enhance the contrast, primarily a modified simultaneous iterative reconstruction technique (SIRT). This effort describes the following systems: particulate randomly distributed in a PF, ash deposition in PFs, a catalyzed washcoat layer in a PF, and three particulate loadings in a SiC PF

  1. 3D neutronic calculations: CAD-MCNP methodology applied to vessel activation in KOYO-F

    Energy Technology Data Exchange (ETDEWEB)

    Herreras, Y; Cabellos, O; Perlado, J M [Instituto de Fusion Nuclear (DENIM)/ETSII/Universidad Politecnica, Madrid (Spain); Lafuente, A; Sordo, F [Universidad Politecnica de Madrid (UPM), Madrid (Spain)], E-mail: yuri@denim.upm.es

    2008-05-15

    This paper presents a methodology for 3D neutronic calculations suitable for complex and extensive geometries. The geometry of the system design is first fully modelled with a CAD program, and subsequently processed through a MCNP-CAD interface in order to generate an MCNP geometry file. Neutronic irradiation results are finally achieved running the MCNPX program, where the geometry input card used is directly the MCNP-CAD interface output. This methodology enables accurate neutronic calculations for complex geometries characterised by high detail levels. This procedure will be applied to the Fast Ignition Fusion Reactor KOYO-F to determine first neutron fluxes calculations along the blanket as well as the material activation in the reduced martensitic 9Cr-1Mo steel vessel.

  2. Applied solid state science advances in materials and device research

    CERN Document Server

    Wolfe, Raymond

    2013-01-01

    Applied Solid State Science: Advances in Materials and Device Research, Volume 4 covers articles on single crystal compound semiconductors and complex polycrystalline materials. The book discusses narrow gap semiconductors and solid state batteries. The text then describes the advantages of hot-pressed microcrystalline compacts of oxygen-octahedra ferroelectrics over single crystal materials, as well as heterostructure junction lasers. Solid state physicists, materials scientists, electrical engineers, and graduate students studying the subjects being discussed will find the book invaluable.

  3. Applied solid state science advances in materials and device research

    CERN Document Server

    Wolfe, Raymond

    2013-01-01

    Applied Solid State Science: Advances in Materials and Device Research, Volume 1 presents articles about junction electroluminescence; metal-insulator-semiconductor (MIS) physics; ion implantation in semiconductors; and electron transport through insulating thin films. The book describes the basic physics of carrier injection; energy transfer and recombination mechanisms; state of the art efficiencies; and future prospects for light emitting diodes. The text then discusses solid state spectroscopy, which is the pair spectra observed in gallium phosphide photoluminescence. The extensive studies

  4. Criticality analysis of thermal reactors for two energy groups applying Monte Carlo and neutron Albedo method

    International Nuclear Information System (INIS)

    The Albedo method applied to criticality calculations to nuclear reactors is characterized by following the neutron currents, allowing to make detailed analyses of the physics phenomena about interactions of the neutrons with the core-reflector set, by the determination of the probabilities of reflection, absorption, and transmission. Then, allowing to make detailed appreciations of the variation of the effective neutron multiplication factor, keff. In the present work, motivated for excellent results presented in dissertations applied to thermal reactors and shieldings, was described the methodology to Albedo method for the analysis criticality of thermal reactors by using two energy groups admitting variable core coefficients to each re-entrant current. By using the Monte Carlo KENO IV code was analyzed relation between the total fraction of neutrons absorbed in the core reactor and the fraction of neutrons that never have stayed into the reflector but were absorbed into the core. As parameters of comparison and analysis of the results obtained by the Albedo method were used one dimensional deterministic code ANISN (ANIsotropic SN transport code) and Diffusion method. The keff results determined by the Albedo method, to the type of analyzed reactor, showed excellent agreement. Thus were obtained relative errors of keff values smaller than 0,78% between the Albedo method and code ANISN. In relation to the Diffusion method were obtained errors smaller than 0,35%, showing the effectiveness of the Albedo method applied to criticality analysis. The easiness of application, simplicity and clarity of the Albedo method constitute a valuable instrument to neutronic calculations applied to nonmultiplying and multiplying media. (author)

  5. Advanced neutron diagnostics for the Nova laser facility

    International Nuclear Information System (INIS)

    Implosion experiments performed on Nova are expected to produce an increased yield of thermonuclear neutrons compared with that of earlier ICF experiments. This yield will make feasible a number of neutron-based measurements heretofore not possible. Laser fusion neutron diagnostics can be divided into two categories: invasive and noninvasive. Invasive techniques require the placement of a tracer material in an interesting region of the target to be activated by the thermonuclear neutrons. Noninvasive techniques involve the energy, spatial, or temporal analysis of the neutrons emitted from the target. After examining a host of diagnostic options from both categories for Nova, the authors decided to pursue both techniques. Ideas for some diagnostic systems are described

  6. Solution of the neutron point kinetics equations with temperature feedback effects applying the polynomial approach method

    Energy Technology Data Exchange (ETDEWEB)

    Tumelero, Fernanda, E-mail: fernanda.tumelero@yahoo.com.br [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Petersen, Claudio Z.; Goncalves, Glenio A.; Lazzari, Luana, E-mail: claudiopeteren@yahoo.com.br, E-mail: gleniogoncalves@yahoo.com.br, E-mail: luana-lazzari@hotmail.com [Universidade Federal de Pelotas (DME/UFPEL), Capao do Leao, RS (Brazil). Instituto de Fisica e Matematica

    2015-07-01

    In this work, we present a solution of the Neutron Point Kinetics Equations with temperature feedback effects applying the Polynomial Approach Method. For the solution, we consider one and six groups of delayed neutrons precursors with temperature feedback effects and constant reactivity. The main idea is to expand the neutron density, delayed neutron precursors and temperature as a power series considering the reactivity as an arbitrary function of the time in a relatively short time interval around an ordinary point. In the first interval one applies the initial conditions of the problem and the analytical continuation is used to determine the solutions of the next intervals. With the application of the Polynomial Approximation Method it is possible to overcome the stiffness problem of the equations. In such a way, one varies the time step size of the Polynomial Approach Method and performs an analysis about the precision and computational time. Moreover, we compare the method with different types of approaches (linear, quadratic and cubic) of the power series. The answer of neutron density and temperature obtained by numerical simulations with linear approximation are compared with results in the literature. (author)

  7. Advanced Neutron Source (ANS) Project: Annual report, April 1987--March 1988

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) Project (formerly called the Center for Neutron Research) will provide the world's best facilities for the study of neutron scattering. The ANS high-power density reactor will be fueled with uranium silicide and cooled, moderated, and reflected by deuterium oxide. Peak neutron fluxes in the reflector are expected to be 5 to 10 x 1019 neutrons/center dot/m-2/center dot/s-1 with a power level between 270 and 300 MW. This report describes the status of technical work funded through the ANS Project during the period April 1987 through March 1988. Earlier work is described in Center for Neutron Research Project Status Report and other Oak Ridge National Laboratory reports. 22 refs., 57 figs., 23 tabs

  8. Advanced Neutron Source (ANS) Project: Annual report, April 1987--March 1988

    Energy Technology Data Exchange (ETDEWEB)

    Selby, D.L.; Harrington, R.M.; Peretz, F.J.; McBee, M.R. (comp.)

    1989-02-01

    The Advanced Neutron Source (ANS) Project (formerly called the Center for Neutron Research) will provide the world's best facilities for the study of neutron scattering. The ANS high-power density reactor will be fueled with uranium silicide and cooled, moderated, and reflected by deuterium oxide. Peak neutron fluxes in the reflector are expected to be 5 to 10 x 10/sup 19/ neutrons/center dot/m/sup -2//center dot/s/sup -1/ with a power level between 270 and 300 MW. This report describes the status of technical work funded through the ANS Project during the period April 1987 through March 1988. Earlier work is described in Center for Neutron Research Project Status Report and other Oak Ridge National Laboratory reports. 22 refs., 57 figs., 23 tabs.

  9. Advanced modeling of prompt fission neutrons and gamma rays

    International Nuclear Information System (INIS)

    Prompt fission neutrons and gamma rays are computed using a Monte Carlo treatment of the statistical evaporation of the excited primary fission fragments. The assumption of two fragments in thermal equilibrium at the time of neutron emission is addressed by studying the neutron multiplicity as a function of fragment mass. Results for the neutron-induced fission of 235U are discussed, for incident neutron energies from 0.5 to 5.5 MeV. Recent experimental data on the fission fragment yields as a function of mass and total kinetic energy are used as input data. Monte-Carlo calculations allow the exploration of physical observables beyond average quantities. A new parameter RT has been introduced: RT=Tl/Th where Tl and Th are the temperatures in the light and heavy fragments. The average neutron multiplicity computed as a function of the fragment mass agrees best with the experimental data (with En=5.5 MeV) when RT=1 which can be understood as follows: as the incident neutron energy increases, the role of shell effects diminishes and the ratio of collective energies stored in the light and heavy fragment tends toward 1

  10. Terrestrial neutron-induced soft errors in advanced memory devices

    CERN Document Server

    Nakamura, Takashi; Ibe, Eishi; Yahagi, Yasuo; Kameyama, Hideaki

    2008-01-01

    Terrestrial neutron-induced soft errors in semiconductor memory devices are currently a major concern in reliability issues. Understanding the mechanism and quantifying soft-error rates are primarily crucial for the design and quality assurance of semiconductor memory devices. This book covers the relevant up-to-date topics in terrestrial neutron-induced soft errors, and aims to provide succinct knowledge on neutron-induced soft errors to the readers by presenting several valuable and unique features. Sample Chapter(s). Chapter 1: Introduction (238 KB). Table A.30 mentioned in Appendix A.6 on

  11. Use of the BD-100R as a neutron spectrometer through applied pressure variation

    Energy Technology Data Exchange (ETDEWEB)

    White, B.; Ebert, D.; Munno, F. (Univ. of Maryland, College Park (USA))

    1991-05-01

    A study was undertaken to demonstrate the feasibility of using the well-characterized BD-100R neutron bubble dosimeter as a neutron spectrometer in low-level radiation fields. The BD-100R dosimeters used in this work consisted of a test tube containing an elastic polymer with interspersed droplets of two types of Freon: Freon-12 and Freon-114. Each superheated liquid droplet is a potential nucleation site, with the minimum energy needed to form a bubble at the nucleation site being inversely proportional to the square of the difference between the applied and the vapor pressure (i.e., Emin alpha(delta P)-2). For a given dose, the number of bubbles formed continually decreases with increasing applied pressure, until a pressure is reached where no bubbles are formed, since the energy transferred can no longer vaporize the Freon. This investigation is intended to demonstrate the feasibility of measuring an unknown spectrum utilizing the dosimeter response (number of bubbles formed) as a function of the neutron energy (applied pressure). A set of 12 dosimeters was exposed under various applied pressures in a well-characterized neutron energy spectrum at the East Beam Port (EBP) of the Maryland University Training Reactor (MUTR). The dosimeters were placed inside a pressure chamber that could accommodate up to 18 dosimeters. Energy response coefficients (cross-sections) were obtained by spectral unfolding techniques on the known spectrum. The same set of dosimeters were then irradiated using a paraffin-moderated Pu/Be source. Measured spectral estimates obtained using the response coefficients were compared with numerical computations generated using the ANISN computer code. The results indicate that further research using the BD-100R as a neutron spectrometer in low radiation fields is warranted.

  12. Conceptual design of a high-intensity positron source for the Advanced Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Hulett, L.D.; Eberle, C.C.

    1994-12-01

    The Advanced Neutron Source (ANS) is a planned new basic and applied research facility based on a powerful steady-state research reactor that provides neutrons for measurements and experiments in the fields of materials science and engineering, biology, chemistry, materials analysis, and nuclear science. The useful neutron flux will be at least five times more than is available in the world`s best existing reactor facility. Construction of the ANS provides a unique opportunity to build a positron spectroscopy facility (PSF) with very-high-intensity beams based on the radioactive decay of a positron-generating isotope. The estimated maximum beam current is 1000 to 5000 times higher than that available at the world`s best existing positron research facility. Such an improvement in beam capability, coupled with complementary detectors, will reduce experiment durations from months to less than one hour while simultaneously improving output resolution. This facility will remove the existing barriers to the routine use of positron-based analytical techniques and will be a giant step toward realization of the full potential of the application of positron spectroscopy to materials science. The ANS PSF is based on a batch cycle process using {sup 64}Cu isotope as the positron emitter and represents the status of the design at the end of last year. Recent work not included in this report, has led to a proposal for placing the laboratory space for the positron experiments outside the ANS containment; however, the design of the positron source is not changed by that relocation. Hydraulic and pneumatic flight tubes transport the source material between the reactor and the positron source where the beam is generated and conditioned. The beam is then transported through a beam pipe to one of several available detectors. The design presented here includes all systems necessary to support the positron source, but the beam pipe and detectors have not been addressed yet.

  13. Advanced in the neutron feedback ICF reactor concept

    International Nuclear Information System (INIS)

    Results are reviewed and updated from an earlier design study of a novel nuclear-pumped flashlamp laser (NP-FL) inertial fusion energy (IFE) power reactor based on the neutron feedback concept for IFE. This concept includes nuclear pumping of the laser flashlamp, a D-T seeded D-3He target and magnetic protection of the first wall of the reactor chamber coupled with direct conversion of deflected charged particles. Advantages include an increased overall plant efficiency due to improved energy coupling via neutron feedback, increased thermal-to-electric energy conversion efficiency, and lower neutron activation and waste. These factors are reflected in a driver energy of 5 MJ and a target gain of only 50 for a 53 % efficient 1000-MWe power plant operating at 6 Hz, novel components involved. However, they require further technological development. Consequently, the NP-FL plant appears to provide a very attractive 'second-generation' IFE reactor. (authors)

  14. Final LDRD report : advanced plastic scintillators for neutron detection.

    Energy Technology Data Exchange (ETDEWEB)

    Vance, Andrew L.; Mascarenhas, Nicholas; O' Bryan, Greg; Mrowka, Stanley

    2010-09-01

    This report summarizes the results of a one-year, feasibility-scale LDRD project that was conducted with the goal of developing new plastic scintillators capable of pulse shape discrimination (PSD) for neutron detection. Copolymers composed of matrix materials such as poly(methyl methacrylate) (PMMA) and blocks containing trans-stilbene (tSB) as the scintillator component were prepared and tested for gamma/neutron response. Block copolymer synthesis utilizing tSBMA proved unsuccessful so random copolymers containing up to 30% tSB were prepared. These copolymers were found to function as scintillators upon exposure to gamma radiation; however, they did not exhibit PSD when exposed to a neutron source. This project, while falling short of its ultimate goal, demonstrated the possible utility of single-component, undoped plastics as scintillators for applications that do not require PSD.

  15. Recent advances in click chemistry applied to dendrimer synthesis.

    Science.gov (United States)

    Arseneault, Mathieu; Wafer, Caroline; Morin, Jean-François

    2015-01-01

    Dendrimers are monodisperse polymers grown in a fractal manner from a central point. They are poised to become the cornerstone of nanoscale devices in several fields, ranging from biomedicine to light-harvesting. Technical difficulties in obtaining these molecules has slowed their transfer from academia to industry. In 2001, the arrival of the "click chemistry" concept gave the field a major boost. The flagship reaction, a modified Hüisgen cycloaddition, allowed researchers greater freedom in designing and building dendrimers. In the last five years, advances in click chemistry saw a wider use of other click reactions and a notable increase in the complexity of the reported structures. This review covers key developments in the click chemistry field applied to dendrimer synthesis from 2010 to 2015. Even though this is an expert review, basic notions and references have been included to help newcomers to the field. PMID:26007183

  16. Recent Advances in Click Chemistry Applied to Dendrimer Synthesis

    Directory of Open Access Journals (Sweden)

    Mathieu Arseneault

    2015-05-01

    Full Text Available Dendrimers are monodisperse polymers grown in a fractal manner from a central point. They are poised to become the cornerstone of nanoscale devices in several fields, ranging from biomedicine to light-harvesting. Technical difficulties in obtaining these molecules has slowed their transfer from academia to industry. In 2001, the arrival of the “click chemistry” concept gave the field a major boost. The flagship reaction, a modified Hüisgen cycloaddition, allowed researchers greater freedom in designing and building dendrimers. In the last five years, advances in click chemistry saw a wider use of other click reactions and a notable increase in the complexity of the reported structures. This review covers key developments in the click chemistry field applied to dendrimer synthesis from 2010 to 2015. Even though this is an expert review, basic notions and references have been included to help newcomers to the field.

  17. Simulation Research on Neutron Guide System CNGC for China Advanced Research Reactor

    Institute of Scientific and Technical Information of China (English)

    WEI; Guo-hai; HAN; Song-bai; HE; Lin-feng; WANG; Yu; WANG; Hong-li; LIU; Yun-tao; CHEN; Dong-feng; ZHAO; Zhi-xiang

    2012-01-01

    <正>The out-pile section of the neutron guide CNGC at CARR (China Advanced Research Reactor) was designed by Monte Carlo simulation with VITESS. The out-pile section of CNGC will be spitted to CNGC-S and CNGC-N, the cold neutron imaging facility and small angle neutron scattering facility will be installed at the end of guides respectively. XRD patterns of Bi1-xLaxFe1-yScyO3 were shown in Fig. 1.

  18. Detailed flux calculations for the conceptual design of the Advanced Neutron Source Reactor

    International Nuclear Information System (INIS)

    A detailed MCNP model of the Advanced Neutron Source Reactor has been developed. All reactor components inside the reflector tank were included, and all components were highly segmented. Neutron and photon multigroup flux spectra have been calculated for each segment in the model, and thermal-to-fast neutron flux ratios were determined for each component segment. Axial profiles of the spectra are provided for all components of the reactor. Individual segment statistical uncertainties were limited wherever possible, and the group fluxes for all important reflector components have a standard deviation below 10%

  19. New generation of cryogen free advanced superconducting magnets for neutron scattering experiments

    Science.gov (United States)

    Kirichek, O.; Brown, J.; Adroja, D. T.; Manuel, P.; Kouzmenko, G.; Bewley, R. I.; Wotherspoon, R.

    2012-12-01

    Recent advances in superconducting technology and cryocooler refrigeration have resulted in a new generation of advanced superconducting magnets for neutron beam applications. These magnets have outstanding parameters such as high homogeneity and stability at highest magnetic fields possible, a reasonably small stray field, low neutron scattering background and larger exposure to neutron detectors. At the same time the pulse tube refrigeration technology provides a complete re-condensing regime which allows to minimise the requirements for cryogens without introducing additional noise and mechanical vibrations. The magnets can be used with dilution refrigerator insert which expands the temperature range from 20mK to 300K. Here we are going to present design, test results and the operational data of the 14T magnet for neutron diffraction and the 9T wide angle chopper magnet for neutron spectroscopy developed by Oxford Instruments in collaboration with ISIS neutron source. First scientific results obtained from the neutron scattering experiments with these magnets are also going to be discussed.

  20. Implementation and Initial Testing of Advanced Processing and Analysis Algorithms for Correlated Neutron Counting

    Energy Technology Data Exchange (ETDEWEB)

    Santi, Peter Angelo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cutler, Theresa Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Favalli, Andrea [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Koehler, Katrina Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henzl, Vladimir [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henzlova, Daniela [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Parker, Robert Francis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Croft, Stephen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-12-01

    In order to improve the accuracy and capabilities of neutron multiplicity counting, additional quantifiable information is needed in order to address the assumptions that are present in the point model. Extracting and utilizing higher order moments (Quads and Pents) from the neutron pulse train represents the most direct way of extracting additional information from the measurement data to allow for an improved determination of the physical properties of the item of interest. The extraction of higher order moments from a neutron pulse train required the development of advanced dead time correction algorithms which could correct for dead time effects in all of the measurement moments in a self-consistent manner. In addition, advanced analysis algorithms have been developed to address specific assumptions that are made within the current analysis model, namely that all neutrons are created at a single point within the item of interest, and that all neutrons that are produced within an item are created with the same energy distribution. This report will discuss the current status of implementation and initial testing of the advanced dead time correction and analysis algorithms that have been developed in an attempt to utilize higher order moments to improve the capabilities of correlated neutron measurement techniques.

  1. Neutron radiography as a non-destructive method for diagnosing neutron converters for advanced thermal neutron detectors

    Science.gov (United States)

    Muraro, A.; Albani, G.; Perelli Cippo, E.; Croci, G.; Angella, G.; Birch, J.; Cazzaniga, C.; Caniello, R.; Dell'Era, F.; Ghezzi, F.; Grosso, G.; Hall-Wilton, R.; Höglund, C.; Hultman, L.; Schimdt, S.; Robinson, L.; Rebai, M.; Salvato, G.; Tresoldi, D.; Vasi, C.; Tardocchi, M.

    2016-03-01

    Due to the well-known problem of 3He shortage, a series of different thermal neutron detectors alternative to helium tubes are being developed, with the goal to find valid candidates for detection systems for the future spallation neutron sources such as the European Spallation Source (ESS). A possible 3He-free detector candidate is a charged particle detector equipped with a three dimensional neutron converter cathode (3D-C). The 3D-C currently under development is composed by a series of alumina (Al2O3) lamellas coated by 1 μ m of 10B enriched boron carbide (B4C). In order to obtain a good characterization in terms of detector efficiency and uniformity it is crucial to know the thickness, the uniformity and the atomic composition of the B4C neutron converter coating. In this work a non-destructive technique for the characterization of the lamellas that will compose the 3D-C was performed using neutron radiography. The results of these measurements show that the lamellas that will be used have coating uniformity suitable for detector applications. This technique (compared with SEM, EDX, ERDA, XPS) has the advantage of being global (i.e. non point-like) and non-destructive, thus it is suitable as a check method for mass production of the 3D-C elements.

  2. Neutron radiography as a non-destructive method for diagnosing neutron converters for advanced thermal neutron detectors

    International Nuclear Information System (INIS)

    Due to the well-known problem of 3He shortage, a series of different thermal neutron detectors alternative to helium tubes are being developed, with the goal to find valid candidates for detection systems for the future spallation neutron sources such as the European Spallation Source (ESS). A possible 3He-free detector candidate is a charged particle detector equipped with a three dimensional neutron converter cathode (3D-C). The 3D-C currently under development is composed by a series of alumina (Al2O3) lamellas coated by 1 μ m of 10B enriched boron carbide (B4C). In order to obtain a good characterization in terms of detector efficiency and uniformity it is crucial to know the thickness, the uniformity and the atomic composition of the B4C neutron converter coating. In this work a non-destructive technique for the characterization of the lamellas that will compose the 3D-C was performed using neutron radiography. The results of these measurements show that the lamellas that will be used have coating uniformity suitable for detector applications. This technique (compared with SEM, EDX, ERDA, XPS) has the advantage of being global (i.e. non point-like) and non-destructive, thus it is suitable as a check method for mass production of the 3D-C elements

  3. Multigroup Albedo Method applied to coupled neutron-gamma radiations shielding

    International Nuclear Information System (INIS)

    Shielding calculations for neutron-gamma radiation are usually done by using the full Theory of Transport or the Monte Carlo Techniques. After some works based on the Albedo Method, the shielding calculations for neutron-gamma radiation have a reliable tool with great didactical value which shows its clarity and simplicity for the resolution of cases that involve neutrons and photon shielding in nonmultiplying media. The excellent results of these works have motivated the elaboration and the development of this study that will be presented in this dissertation. The balance of a neutronic current entering a shield of two layers considering the coupling neutron-gamma will be determined by the Albedo Method. The shield will be composed of a layer of iron and another one of manganese with 10 cm of thickness each. The arrays of the materials coefficients will be obtained from the ANISN code. ANISN is a one dimensional deterministic code that is based on transport equation. The final results obtained by the Albedo Method will be compared with the ANISN results for an order of angular quadrature S2. The angular quadrature S2 admits that the radiation has two routes in the same direction what better describes the Albedo Method behavior. The results obtained by using the Albedo Method show an excellent agreement with the values predicted by the adopted deterministic code ANISN. Due to the excellent results, the multigroup Albedo Method should be applied to the shielding calculations with multiple layers. In conclusion the multigroup Albedo Method has the great ability in solving shielding problems concerning to the Nuclear Engineering. (author)

  4. Advances in passive neutron instruments for safeguards use

    International Nuclear Information System (INIS)

    Passive neutron and other nondestructive assay techniques have been used extensively by the International Atomic Energy Agency to verify plutonium metal, powder, mixed oxide, pellets, rods, assemblies, scrap, and liquids. Normally, the coincidence counting rate is used to measure the 240Pu-effective mass and gamma-ray spectrometry or mass spectrometry is used to verify the plutonium isotopic ratios. During the past few years, the passive neutron detectors have been installed in plants and operated in the unattended/continuous mode. These radiation data with time continuity have made it possible to use the totals counting rate to monitor the movement of nuclear material. Monte Carlo computer codes have been used to optimize the detector designs for specific applications. The inventory sample counter (INVS-III) has been designed to have a higher efficiency (43%) and a larger uniform counting volume than the original INVS. Data analyses techniques have been developed, including the ''known alpha'' and ''known multiplication'' methods that depend on the sample. For scrap and other impure or poorly characterized samples, we have developed multiplicity counting, initially implemented in the plutonium scrap multiplicity counter. For large waste containers such as 200-L drums, we have developed the add-a-source technique to give accurate corrections for the waste-matrix materials. This paper summarizes recent developments in the design and application of passive neutron assay systems

  5. Advances in passive neutron instruments for safeguards use

    Energy Technology Data Exchange (ETDEWEB)

    Menlove, H.O.; Krick, M.S.; Langner, D.G.; Miller, M.C.; Stewart, J.E.

    1994-02-01

    Passive neutron and other nondestructive assay techniques have been used extensively by the International Atomic Energy Agency to verify plutonium metal, powder, mixed oxide, pellets, rods, assemblies, scrap, and liquids. Normally, the coincidence counting rate is used to measure the {sup 240}Pu-effective mass and gamma-ray spectrometry or mass spectrometry is used to verify the plutonium isotopic ratios. During the past few years, the passive neutron detectors have been installed in plants and operated in the unattended/continuous mode. These radiation data with time continuity have made it possible to use the totals counting rate to monitor the movement of nuclear material. Monte Carlo computer codes have been used to optimize the detector designs for specific applications. The inventory sample counter (INVS-III) has been designed to have a higher efficiency (43%) and a larger uniform counting volume than the original INVS. Data analyses techniques have been developed, including the ``known alpha`` and ``known multiplication`` methods that depend on the sample. For scrap and other impure or poorly characterized samples, we have developed multiplicity counting, initially implemented in the plutonium scrap multiplicity counter. For large waste containers such as 200-L drums, we have developed the add-a-source technique to give accurate corrections for the waste-matrix materials. This paper summarizes recent developments in the design and application of passive neutron assay systems.

  6. Recent advances and future trends in neutron resonance spectroscopy

    International Nuclear Information System (INIS)

    Neutron resonance spectroscopy contributes primarily to two areas of nuclear physics: 1.) in medium weight and heavy nuclei with a high level density it tests their statistical properties, and 2.) in nuclei with a sufficiently low level density, i.e. light nuclei (A ≤ 50) and nuclei around /sup 208/Pb, it investigates nuclear structure at several MeV excitation energy. In the first field, recent years have seen growing knowledge and understanding of nuclear level densities and their spin and parity dependence. Several questions basic to the statistical properties of nuclei, although extensively studied in the past, are still open: the statistical distribution of partial widths; possible narrow energy variations of the average partial widths; and correlations between partial widths for different reaction channels. The major progress has occurred and will continue to take place in the field of light nuclei: improved resolution of neutron time-of-flight spectrometers yields detailed resonance data over an extended energy range, and model calculations become possible which will allow detailed comparison to experimental data. The main subjects of interest are the distributions of neutron, as well as radiative strengths and their interpretation in terms of nuclear structure

  7. Recent advances and future trends in neutron resonance spectroscopy

    International Nuclear Information System (INIS)

    Neutron resonance spectroscopy contributes primarily to two areas of nuclear physics: In medium weight and heavy nuclei with a high level density it tests their statistical properties; in nuclei with a sufficiently low level density, i.e. light nuclei (A 208Pb, it investigates nuclear structure at several MeV excitation energy. In the first field, recent years have seen growing knowledge and understanding of nuclear level densities and their spin and parity dependence. Several questions basic to the statistical properties of nuclei, although extensively studied in the past, are still open: the statistical distribution of partial widths; possible narrow energy variations of the average partial widths; and correlations between partial widths for different reaction channels. The major progress has occured and will continue to take place in the field of light nuclei: Improved resolution of neutron time-of-flight spectrometers yields detailed resonance data over an extended energy range, and model calculations become possible which will allow detailed comparison to experimental data. The main subjects of interest are the distributions of neutron- as well as radiative strengths and their interpretation in terms of nuclear structure. (author)

  8. Induction heating of a spherical aluminum moderator vessel for the Advanced Neutron Source (ANS)

    International Nuclear Information System (INIS)

    This task was to identify and design a heating system to apply 15 kW of heat to a cold source vessel to simulate the Advanced Neutron Source reactor. This research project aims at the analysis of the induction heating of a spherical aluminum moderator vessel. Computer modeling is presented for the design and analysis of the induction heating system. The objective is to apply 15 kW of heat as uniformly as possible to the outer wall of a 410 mm diameter sphere of thickness 1.5 mm. The report also aims at the analysis of a system model which is simulated using the Eddycuff electromagnetic software. The computer model is built with the finite element analysis software Patran. The induction heating system analysis shows that the predicted performance is in close agreement with the computer simulated data. Hardware constraints such as power supplies and matching load are also analyzed in terms of performance and cost. Physical modeling is also suggested, in which the coil and the workpiece are scaled down

  9. ORNL contributions to the Advanced Neutron Source (ANS) Project for October 1986-March 1987

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) Facility - formerly called the Center for Neutron Research - will provide the world's best facilities for the study of neutron scattering. The ANS high power density reactor will be fueled with uranium silicide and cooled, moderated, and reflected by D2O. Peak neutron fluxes in the reflector are expected to be 5 to 10 x 1019 neutrons per square meter with a power level between 270 MW and 300 MW. This report describes the status of technical work at ORNL on the ANS Project during the first half of FY 1987. The scope of this report includes Research and Development Tasks; Safety Tasks; Conceptual Design Tasks; and Project Support. The last two areas were only initiated as separate activities during this reporting period. Technical highlights include a better understanding of the relationship among neutron flux, core power, and core volume; preconceptual design work on a cold source for use in a very high gamma and neutron flux environment; identification of the major applicable safety rules and guidelines; and establishment of initial functional objectives for the containment structure

  10. Hardening neutron spectrum for advanced actinide transmutation experiments in the ATR.

    Science.gov (United States)

    Chang, G S; Ambrosek, R G

    2005-01-01

    The most effective method for transmuting long-lived isotopes contained in spent nuclear fuel into shorter-lived fission products is in a fast neutron spectrum reactor. In the absence of a fast test reactor in the United States, initial irradiation testing of candidate fuels can be performed in a thermal test reactor that has been modified to produce a test region with a hardened neutron spectrum. Such a test facility, with a spectrum similar but somewhat softer than that of the liquid-metal fast breeder reactor (LMFBR), has been constructed in the INEEL's Advanced Test Reactor (ATR). The radial fission power distribution of the actinide fuel pin, which is an important parameter in fission gas release modelling, needs to be accurately predicted and the hardened neutron spectrum in the ATR and the LMFBR fast neutron spectrum is compared. The comparison analyses in this study are performed using MCWO, a well-developed tool that couples the Monte Carlo transport code MCNP with the isotope depletion and build-up code ORIGEN-2. MCWO analysis yields time-dependent and neutron-spectrum-dependent minor actinide and Pu concentrations and detailed radial fission power profile calculations for a typical fast reactor (LMFBR) neutron spectrum and the hardened neutron spectrum test region in the ATR. The MCWO-calculated results indicate that the cadmium basket used in the advanced fuel test assembly in the ATR can effectively depress the linear heat generation rate in the experimental fuels and harden the neutron spectrum in the test region.

  11. Advanced Neutron Source (ANS) Project. Progress report FY 1993

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, J.H. [ed.; Selby, D.L.; Harrington, R.M. [Oak Ridge National Lab., TN (United States); Thompson, P.B. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States). Engineering Div.

    1994-01-01

    This report covers the progress made in 1993 in the following sections: (1) project management; (2) research and development; (3) design and (4) safety. The section on research and development covers the following: (1) reactor core development; (2) fuel development; (3) corrosion loop tests and analysis; (4) thermal-hydraulic loop tests; (5) reactor control and shutdown concepts; (6) critical and subcritical experiments; (7) material data, structure tests, and analysis; (8) cold source development; (9) beam tube, guide, and instrument development; (10) neutron transport and shielding; (11) I and C research and development; and (12) facility concepts.

  12. Advances in thermal hydraulic and neutronic simulation for reactor analysis and safety

    Energy Technology Data Exchange (ETDEWEB)

    Tentner, A.M.; Blomquist, R.N.; Canfield, T.R.; Ewing, T.F.; Garner, P.L.; Gelbard, E.M.; Gross, K.C.; Minkoff, M.; Valentin, R.A.

    1993-03-01

    This paper describes several large-scale computational models developed at Argonne National Laboratory for the simulation and analysis of thermal-hydraulic and neutronic events in nuclear reactors and nuclear power plants. The impact of advanced parallel computing technologies on these computational models is emphasized.

  13. An examination of the elastic structural response of the Advanced Neutron Source fuel plates

    Energy Technology Data Exchange (ETDEWEB)

    Swinson, W.F.; Luttrell, C.R.; Yahr, G.T.

    1994-09-01

    Procedures for evaluating the elastic structural response of the Advanced Neutron Source (ANS) fuel plates to coolant flow and to temperature variations are presented in this report. Calculations are made that predict the maximum deflection and the maximum stress for a representative plate from the upper and from the lower fuel elements.

  14. Detecting binary neutron star systems with spin in advanced gravitational-wave detectors

    CERN Document Server

    Brown, Duncan A; Lundgren, Andrew; Nitz, Alexander H

    2012-01-01

    The detection of gravitational waves from binary neutron stars is a major goal of the gravitational-wave observatories Advanced LIGO and Advanced Virgo. Previous searches for binary neutron stars with LIGO and Virgo neglected the component stars' angular momentum (spin). We demonstrate that neglecting spin in matched-filter searches causes advanced detectors to lose more than 3% of the possible signal-to-noise ratio for 59% (6%) of sources, assuming that neutron star dimensionless spins, $cJ/GM^2$, are uniformly distributed with magnitudes between 0 and 0.4 (0.05) and that the neutron stars have isotropically distributed spin orientations. We present a new method of constructing filter banks for advanced-detector searches, which can create template banks of signals with non-zero spins that are (anti-)aligned with the orbital angular momentum. We show that this search loses more than 3% of the maximium signal-to-noise for only 9% (0.2%) of BNS sources with dimensionless spins between 0 and 0.4 (0.05) and isotr...

  15. Monte Carlo simulations to advance characterisation of landmines by pulsed fast/thermal neutron analysis

    NARCIS (Netherlands)

    Maucec, M.; Rigollet, C.

    2004-01-01

    The performance of a detection system based on the pulsed fast/thermal neutron analysis technique was assessed using Monte Carlo simulations. The aim was to develop and implement simulation methods, to support and advance the data analysis techniques of the characteristic gamma-ray spectra, potentia

  16. Measuring neutron star tidal deformability with Advanced LIGO: a Bayesian analysis of neutron star - black hole binary observations

    CERN Document Server

    Kumar, Prayush; Pfeiffer, Harald P

    2016-01-01

    The discovery of gravitational waves (GW) by Advanced LIGO has ushered us into an era of observational GW astrophysics. Compact binaries remain the primary target sources for LIGO, of which neutron star-black hole (NSBH) binaries form an important subset. GWs from NSBH sources carry signatures of (a) the tidal distortion of the neutron star by its companion black hole during inspiral, and (b) its potential tidal disruption near merger. In this paper, we present a Bayesian study of the measurability of neutron star tidal deformability $\\Lambda_\\mathrm{NS}\\propto (R/M)^{5}$ using observation(s) of inspiral-merger GW signals from disruptive NSBH coalescences, taking into account the crucial effect of black hole spins. First, we find that if non-tidal templates are used to estimate source parameters for an NSBH signal, the bias introduced in the estimation of non-tidal physical parameters will only be significant for loud signals with signal-to-noise ratios greater than $30$. For similarly loud signals, we also f...

  17. Advances in Atomic Data for Neutron-Capture Elements

    CERN Document Server

    Sterling, N C; Esteves, D A; Stancil, P C; Kilcoyne, A L D; Bilodeau, R C; Aguilar, A

    2011-01-01

    Neutron(n)-capture elements (atomic number Z>30), which can be produced in planetary nebula (PN) progenitor stars via s-process nucleosynthesis, have been detected in nearly 100 PNe. This demonstrates that nebular spectroscopy is a potentially powerful tool for studying the production and chemical evolution of trans-iron elements. However, significant challenges must be addressed before this goal can be achieved. One of the most substantial hurdles is the lack of atomic data for n-capture elements, particularly that needed to solve for their ionization equilibrium (and hence to convert ionic abundances to elemental abundances). To address this need, we have computed photoionization cross sections and radiative and dielectronic recombination rate coefficients for the first six ions of Se and Kr. The calculations were benchmarked against experimental photoionization cross section measurements. In addition, we computed charge transfer (CT) rate coefficients for ions of six n-capture elements. These efforts will ...

  18. Thermal-hydraulic studies of the Advanced Neutron Source cold source

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS), in its conceptual design phase at Oak Ridge National Laboratory, was to be a user-oriented neutron research facility producing the most intense steady-state flux of thermal and cold neutrons in the world. Among its many scientific applications, the production of cold neutrons was a significant research mission for the ANS. The cold neutrons come from two independent cold sources positioned near the reactor core. Contained by an aluminum alloy vessel, each cold source is a 410-mm-diam sphere of liquid deuterium that functions both as a neutron moderator and a cryogenic coolant. With nuclear heating of the containment vessel and internal baffling, steady-state operation requires close control of the liquid deuterium flow near the vessel's inner surface. Preliminary thermal-hydraulic analyses supporting the cold source design were performed with heat conduction simulations of the vessel walls and multidimensional computational fluid dynamics simulations of the liquid deuterium flow and heat transfer. This report presents the starting phase of a challenging program and describes the cold source conceptual design, the thermal-hydraulic feasibility studies of the containment vessel, and the future computational and experimental studies that were planned to verify the final design

  19. Development of Advanced Multi-Modality Radiation Treatment Planning Software for Neutron Radiotherapy and Beyond

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, D; Wessol, D; Wemple, C; Harkin, G; Hartmann-Siantar, C

    2002-08-20

    The Idaho National Engineering and Environmental Laboratory (INEEL) has long been active in development of advanced Monte-Carlo based computational dosimetry and treatment planning methods and software for advanced radiotherapy, with a particular focus on Neutron Capture Therapy (NCT) and, to a somewhat lesser extent, Fast-Neutron Therapy. The most recent INEEL software system of this type is known as SERA, Simulation Environment for Radiotherapy Applications. As a logical next step in the development of modern radiotherapy planning tools to support the most advanced research, INEEL and Lawrence Livermore National Laboratory (LLNL), the developers of the PEREGRTNE computational engine for radiotherapy treatment planning applications, have recently launched a new project to collaborate in the development of a ''next-generation'' multi-modality treatment planning software system that will be useful for all modern forms of radiotherapy.

  20. Thermophysical properties of saturated light and heavy water for Advanced Neutron Source applications

    Energy Technology Data Exchange (ETDEWEB)

    Crabtree, A.; Siman-Tov, M.

    1993-05-01

    The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor`s nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300{degrees}C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250{degrees}C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

  1. Thermophysical properties of saturated light and heavy water for advanced neutron source applications

    Energy Technology Data Exchange (ETDEWEB)

    Crabtree, A.; Siman-Tov, M.

    1993-05-01

    The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor's nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300[degrees]C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250[degrees]C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

  2. Boron neutron capture therapy outcomes for advanced or recurrent head and neck cancer

    International Nuclear Information System (INIS)

    We retrospectively review outcomes of applying boron neutron capture therapy (BNCT) to unresectable advanced or recurrent head and neck cancers. Patients who were treated with BNCT for either local recurrent or newly diagnosed unresectable head or neck cancers between December 2001 and September 2007 were included. Clinicopathological characteristics and clinical outcomes were retrieved from hospital records. Either a combination of borocaptate sodium and boronophenylalanine (BPA) or BPA alone were used as boron compounds. In all the treatment cases, the dose constraint was set to deliver a dose <10–12 Gy-eq to the skin or oral mucosa. There was a patient cohort of 62, with a median follow-up of 18.7 months (range, 0.7–40.8). A total of 87 BNCT procedures were performed. The overall response rate was 58% within 6 months after BNCT. The median survival time was 10.1 months from the time of BNCT. The 1- and 2-year overall survival (OS) rates were 43.1% and 24.2%, respectively. The major acute Grade 3 or 4 toxicities were hyperamylasemia (38.6%), fatigue (6.5%), mucositis/stomatitis (9.7%) and pain (9.7%), all of which were manageable. Three patients died of treatment-related toxicity. Three patients experienced carotid artery hemorrhage, two of whom had coexistent infection of the carotid artery. This study confirmed the feasibility of our dose-estimation method and that controlled trials are warranted. (author)

  3. Measurements of neutron cross sections for advanced nuclear energy systems at n_TOF (CERN

    Directory of Open Access Journals (Sweden)

    Barbagallo M.

    2014-03-01

    Full Text Available The n_TOF facility operates at CERN with the aim of addressing the request of high accuracy nuclear data for advanced nuclear energy systems as well as for nuclear astrophysics. Thanks to the features of the neutron beam, important results have been obtained on neutron induced fission and capture cross sections of U, Pu and minor actinides. Recently the construction of another beam line has started; the new line will be complementary to the first one, allowing to further extend the experimental program foreseen for next measurement campaigns.

  4. Advances in neutron capture therapy 2006. Proceedings of 12th international congress on neutron capture therapy

    International Nuclear Information System (INIS)

    The Twelfth International Congress on Neutron Capture Therapy (ICNCT-12) is being held from October 9th to 13th, 2006 at the Kagawa International Congress Hall in Takamatsu, Kagawa, Japan. The main theme of the congress is From the past to the Future'. Five symposiums were organized to accommodate all the contributions from the international scientific committees of the International Society for Neutron Capture Therapy (ISNCT), and two symposiums were added to balance the number of fields of specialties. The seven symposiums for ICNCT-12 are as follows: 1) Clinical Results of BNCT for Brain Tumors, 2) Dosimetry, 3) Treatment Planning system, 4) Drug Delivery System, 5) Biomedical and General Matters, 6) BNCT Systems using Accelerators, 7) New Applications and Protocols for BNCT. There are a total of 195 presentations in this congress: 3 special lectures, 34 symposium presentations, 10 presentations in two special sessions from the recipients of the Ralph G. Fairchild Award, 70 presentations in the oral parallel sessions and 78 presentations in the poster sessions. A compilation of 169 papers are published in this proceedings. The 165 of the presented papers are indexed individually. (J.P.N.)

  5. Electromagnetic Signatures of Neutron Star Mergers in the Advanced LIGO Era

    CERN Document Server

    Fernández, Rodrigo

    2015-01-01

    The mergers of binaries containing neutron stars and stellar-mass black holes are the most promising sources for direct detection in gravitational waves by the interferometers Advanced LIGO and Virgo over the next few years. The concurrent detection of electromagnetic emission from these events would greatly enhance the scientific return of these discoveries. Here we review the state of the art in modeling the electromagnetic signal of neutron star binary mergers across different phases of the merger and multiple wavelengths. We focus on those observables which provide the most sensitive diagnostics of the merger physics and the contribution to the synthesis of rapid neutron capture ($r$-process) elements in the Galaxy. We also outline expected future developments on the observational and theoretical sides of this rapidly evolving field.

  6. Report on the meeting of the working groups on neutron scattering applied to studying condensed matter, and neutron scattering and complementary methods applied in chemistry and biology

    International Nuclear Information System (INIS)

    The present volume consists of 55 lectures. The subjects are: 1) Elastic neutron diffraction, 2) Lattice dynamics, 3) Diffusion, 4) Polymers, 5) Biology, 6) Methods and tools, 7) Magnetism. For distinct papers see hints under relevant topics. (BHO)

  7. Scientific Advancements and Technological Developments of High P-T Neutron Diffraction at LANSCE, Los Alamos

    Science.gov (United States)

    Zhao, Y.; Daemen, L. L.; Zhang, J.

    2003-12-01

    In-situ high P-T neutron diffraction experiments provide unique opportunities to study the crystal structure, hydrogen bonding, magnetism, and thermal parameters of light elements (eg. H, Li, B) and heavy elements (eg. Ta, U, Pu,), that are virtually impossible to determine with x-ray diffraction techniques. For example, thermoelasticity and Debye-Waller factor as function of pressure and temperature can be derived using in-situ high P-T neutron diffraction techniques. These applications can also be extended to a much broader spectrum of scientific problems. For instance, puzzles in Earth science such as the carbon cycle and the role of hydrous minerals for water exchange between lithosphere and biosphere can be directly addressed. Moreover, by introducing in-situ shear, texture of metals and minerals accompanied with phase transitions at high P-T conditions can also be studied by high P-T neutron diffraction. We have successfully conducted high P-T neutron diffraction experiments at LANSCE and achieved simultaneous high pressures and temperatures of 10 GPa and 1500 K. With an average 3-6 hours of data collection, the diffraction data are of sufficiently high quality for the determination of structural parameters and thermal vibrations. We have studied hydrous mineral (MgOD), perovskite (K.15,Na.85)MgF3, clathrate hydrates (CH4-, CO2-, and H2-), metals (Mo, Al, Zr), and amorphous materials (carbon black, BMG). The aim of our research is to accurately map bond lengths, bond angles, neighboring atomic environments, and phase stability in P-T-X space. Studies based on high-pressure neutron diffraction are important for multi-disciplinary science and we welcome researchers from all fields to use this advanced technique. We have developed a 500-ton toroidal press, TAP-98, to conduct simultaneous high P-T neutron diffraction experiments inside of HIPPO (High-Pressure and Preferred-Orientation diffractometer). We have also developed a large gem-crystal anvil cell, ZAP-01

  8. PREFACE: Exploring surfaces and buried interfaces of functional materials by advanced x-ray and neutron techniques Exploring surfaces and buried interfaces of functional materials by advanced x-ray and neutron techniques

    Science.gov (United States)

    Sakurai, Kenji

    2010-12-01

    This special issue is devoted to describing recent applications of x-ray and neutron scattering techniques to the exploration of surfaces and buried interfaces of various functional materials. Unlike many other surface-sensitive methods, these techniques do not require ultra high vacuum, and therefore, a variety of real and complicated surfaces fall within the scope of analysis. It must be particularly emphasized that the techniques are capable of seeing even buried function interfaces as well as the surface. Furthermore, the information, which ranges from the atomic to mesoscopic scale, is highly quantitative and reproducible. The non-destructive nature of the techniques is another important advantage of using x-rays and neutrons, when compared with other atomic-scale analyses. This ensures that the same specimen can be measured by other techniques. Such features are fairly attractive when exploring multilayered materials with nanostructures (dots, tubes, wires, etc), which are finding applications in electronic, magnetic, optical and other devices. The Japan Applied Physics Society has established a group to develop the research field of studying buried function interfaces with x-rays and neutrons. As the methods can be applied to almost all types of materials, from semiconductor and electronic devices to soft materials, participants have fairly different backgrounds but share a common interest in state-of-the-art x-ray and neutron techniques and sophisticated applications. A series of workshops has been organized almost every year since 2001. Some international interactions have been continued intensively, although the community is part of a Japanese society. This special issue does not report the proceedings of the recent workshop, although all the authors are in some way involved in the activities of the above society. Initially, we intended to collect quite long overview papers, including the authors' latest and most important original results, as well as

  9. Fast neutron spectrometry with organic scintillators applied to magnetic fusion experiments

    CERN Document Server

    Kaschuck, Y A; Trykov, L A; Semenov, V P

    2002-01-01

    Neutron spectrometry with NE213 liquid scintillators is commonly used in thermonuclear fusion experiments to measure the 2.45 and 14.1 MeV neutron flux. We present the unfolded neutron spectrum, which was accumulated during several ohmic deuterium plasma discharges in the Frascati Tokamak Upgrade using a 2''x2'' NE213 scintillator. In this paper, we review the application of organic scintillator neutron spectrometers to tokamaks, focusing in particular on the comparison between NE213 and stilbene scintillators. Various aspects of the calibration technique and neutron spectra unfolding procedure are considered in the context of their application for fusion neutron spectrometry. Testing and calibration measurements have been carried out using D-D and D-T neutron generator facilities with both NE213 and stilbene scintillators. The main result from these measurements is that stilbene scintillator has better neutron energy resolution than NE213. Our stilbene detector could be used for the determination of the ion ...

  10. Upper limits on the rates of binary neutron star and neutron-star--black-hole mergers from Advanced LIGO's first observing run

    CERN Document Server

    Abbott, B P; Abbott, T D; Abernathy, M R; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Adya, V B; Affeldt, C; Agathos, M; Agatsuma, K; Aggarwal, N; Aguiar, O D; Aiello, L; Ain, A; Ajith, P; Allen, B; Allocca, A; Altin, P A; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C C; Areeda, J S; Arnaud, N; Arun, K G; Ascenzi, S; Ashton, G; Ast, M; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Babak, S; Bacon, P; Bader, M K M; Baker, P T; Baldaccini, F; Ballardin, G; Ballmer, S W; Barayoga, J C; Barclay, S E; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barta, D; Bartlett, J; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Baune, C; Bavigadda, V; Bazzan, M; Bejger, M; Bell, A S; Berger, B K; Bergmann, G; Berry, C P L; Bersanetti, D; Bertolini, A; Betzwieser, J; Bhagwat, S; Bhandare, R; Bilenko, I A; Billingsley, G; Birch, J; Birney, R; Biscans, S; Bisht, A; Bitossi, M; Biwer, C; Bizouard, M A; Blackburn, J K; Blair, C D; Blair, D G; Blair, R M; Bloemen, S; Bock, O; Boer, M; Bogaert, G; Bogan, C; Bohe, A; Bond, C; Bondu, F; Bonnand, R; Boom, B A; Bork, R; Boschi, V; Bose, S; Bouffanais, Y; Bozzi, A; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Brillet, A; Brinkmann, M; Brisson, V; Brockill, P; Broida, J E; Brooks, A F; Brown, D A; Brown, D D; Brown, N M; Brunett, S; Buchanan, C C; Buikema, A; Bulik, T; Bulten, H J; Buonanno, A; Buskulic, D; Buy, C; Byer, R L; Cabero, M; Cadonati, L; Cagnoli, G; Cahillane, C; Bustillo, J Calder'on; Callister, T; Calloni, E; Camp, J B; Cannon, K C; Cao, J; Capano, C D; Capocasa, E; Carbognani, F; Caride, S; Diaz, J Casanueva; Casentini, C; Caudill, S; Cavagli`a, M; Cavalier, F; Cavalieri, R; Cella, G; Cepeda, C B; Baiardi, L Cerboni; Cerretani, G; Cesarini, E; Chamberlin, S J; Chan, M; Chao, S; Charlton, P; Chassande-Mottin, E; Cheeseboro, B D; Chen, H Y; Chen, Y; Cheng, C; Chincarini, A; Chiummo, A; Cho, H S; Cho, M; Chow, J H; Christensen, N; Chu, Q; Chua, S; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P -F; Colla, A; Collette, C G; Cominsky, L; Constancio, M; Conte, A; Conti, L; Cook, D; Corbitt, T R; Cornish, N; Corsi, A; Cortese, S; Costa, C A; Coughlin, M W; Coughlin, S B; Coulon, J -P; Countryman, S T; Couvares, P; Cowan, E E; Coward, D M; Cowart, M J; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Cripe, J; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Canton, T Dal; Danilishin, S L; D'Antonio, S; Danzmann, K; Darman, N S; Dasgupta, A; Costa, C F Da Silva; Dattilo, V; Dave, I; Davier, M; Davies, G S; Daw, E J; Day, R; De, S; DeBra, D; Debreczeni, G; Degallaix, J; De Laurentis, M; Del'eglise, S; Del Pozzo, W; Denker, T; Dent, T; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Devine, R C; Dhurandhar, S; D'iaz, M C; Di Fiore, L; Di Giovanni, M; Di Girolamo, T; Di Lieto, A; Di Pace, S; Di Palma, I; Di Virgilio, A; Dolique, V; Donovan, F; Dooley, K L; Doravari, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Ducrot, M; Dwyer, S E; Edo, T B; Edwards, M C; Effler, A; Eggenstein, H -B; Ehrens, P; Eichholz, J; Eikenberry, S S; Engels, W; Essick, R C; Etzel, T; Evans, M; Evans, T M; Everett, R; Factourovich, M; Fafone, V; Fair, H; Fairhurst, S; Fan, X; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fays, M; Fehrmann, H; Fejer, M M; Fenyvesi, E; Ferrante, I; Ferreira, E C; Ferrini, F; Fidecaro, F; Fiori, I; Fiorucci, D; Fisher, R P; Flaminio, R; Fletcher, M; Fournier, J -D; Frasca, S; Frasconi, F; Frei, Z; Freise, A; Frey, R; Frey, V; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gabbard, H A G; Gair, J R; Gammaitoni, L; Gaonkar, S G; Garufi, F; Gaur, G; Gehrels, N; Gemme, G; Geng, P; Genin, E; Gennai, A; George, J; Gergely, L; Germain, V; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, K; Glaefke, A; Goetz, E; Goetz, R; Gondan, L; Gonz'alez, G; Castro, J M Gonzalez; Gopakumar, A; Gordon, N A; Gorodetsky, M L; Gossan, S E; Gosselin, M; Gouaty, R; Grado, A; Graef, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greco, G; Green, A C; Groot, P; Grote, H; Grunewald, S; Guidi, G M; Guo, X; Gupta, A; Gupta, M K; Gushwa, K E; Gustafson, E K; Gustafson, R; Hacker, J J; Hall, B R; Hall, E D; Hammond, G; Haney, M; Hanke, M M; Hanks, J; Hanna, C; Hannam, M D; Hanson, J; Hardwick, T; Harms, J; Harry, G M; Harry, I W; Hart, M J; Hartman, M T; Haster, C -J; Haughian, K; Heidmann, A; Heintze, M C; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Hennig, J; Henry, J; Heptonstall, A W; Heurs, M; Hild, S; Hoak, D; Hofman, D; Holt, K; Holz, D E; Hopkins, P; Hough, J; Houston, E A; Howell, E J; Hu, Y M; Huang, S; Huerta, E A; Huet, D; Hughey, B; Husa, S; Huttner, S H; Huynh-Dinh, T; Indik, N; Ingram, D R; Inta, R; Isa, H N; Isac, J -M; Isi, M; Isogai, T; Iyer, B R; Izumi, K; Jacqmin, T; Jang, H; Jani, K; Jaranowski, P; Jawahar, S; Jian, L; Jim'enez-Forteza, F; Johnson, W W; Jones, D I; Jones, R; Jonker, R J G; Ju, L; K, Haris; Kalaghatgi, C V; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Kapadia, S J; Karki, S; Karvinen, K S; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, S; Kaur, T; Kawabe, K; K'ef'elian, F; Kehl, M S; Keitel, D; Kelley, D B; Kells, W; Kennedy, R; Key, J S; Khalili, F Y; Khan, I; Khan, S; Khan, Z; Khazanov, E A; Kijbunchoo, N; Kim, Chi-Woong; Kim, Chunglee; Kim, J; Kim, K; Kim, N; Kim, W; Kim, Y -M; Kimbrell, S J; King, E J; King, P J; Kissel, J S; Klein, B; Kleybolte, L; Klimenko, S; Koehlenbeck, S M; Koley, S; Kondrashov, V; Kontos, A; Korobko, M; Korth, W Z; Kowalska, I; Kozak, D B; Kringel, V; Krishnan, B; Kr'olak, A; Krueger, C; Kuehn, G; Kumar, P; Kumar, R; Kuo, L; Kutynia, A; Lackey, B D; Landry, M; Lange, J; Lantz, B; Lasky, P D; Laxen, M; Lazzarini, A; Lazzaro, C; Leaci, P; Leavey, S; Lebigot, E O; Lee, C H; Lee, H K; Lee, H M; Lee, K; Lenon, A; Leonardi, M; Leong, J R; Leroy, N; Letendre, N; Levin, Y; Lewis, J B; Li, T G F; Libson, A; Littenberg, T B; Lockerbie, N A; Lombardi, A L; London, L T; Lord, J E; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lough, J D; L"uck, H; Lundgren, A P; Lynch, R; Ma, Y; Machenschalk, B; MacInnis, M; Macleod, D M; Magana-Sandoval, F; Zertuche, L Magana; Magee, R M; Majorana, E; Maksimovic, I; Malvezzi, V; Man, N; Mandic, V; Mangano, V; Mansell, G L; Manske, M; Mantovani, M; Marchesoni, F; Marion, F; M'arka, S; M'arka, Z; Markosyan, A S; Maros, E; Martelli, F; Martellini, L; Martin, I W; Martynov, D V; Marx, J N; Mason, K; Masserot, A; Massinger, T J; Masso-Reid, M; Mastrogiovanni, S; Matichard, F; Matone, L; Mavalvala, N; Mazumder, N; McCarthy, R; McClelland, D E; McCormick, S; McGuire, S C; McIntyre, G; McIver, J; McManus, D J; McRae, T; McWilliams, S T; Meacher, D; Meadors, G D; Meidam, J; Melatos, A; Mendell, G; Mercer, R A; Merilh, E L; Merzougui, M; Meshkov, S; Messenger, C; Messick, C; Metzdorff, R; Meyers, P M; Mezzani, F; Miao, H; Michel, C; Middleton, H; Mikhailov, E E; Milano, L; Miller, A L; Miller, A; Miller, B B; Miller, J; Millhouse, M; Minenkov, Y; Ming, J; Mirshekari, S; Mishra, C; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Moggi, A; Mohan, M; Mohapatra, S R P; Montani, M; Moore, B C; Moore, C J; Moraru, D; Moreno, G; Morriss, S R; Mossavi, K; Mours, B; Mow-Lowry, C M; Mueller, G; Muir, A W; Mukherjee, Arunava; Mukherjee, D; Mukherjee, S; Mukund, N; Mullavey, A; Munch, J; Murphy, D J; Murray, P G; Mytidis, A; Nardecchia, I; Naticchioni, L; Nayak, R K; Nedkova, K; Nelemans, G; Nelson, T J N; Neri, M; Neunzert, A; Newton, G; Nguyen, T T; Nielsen, A B; Nissanke, S; Nitz, A; Nocera, F; Nolting, D; Normandin, M E N; Nuttall, L K; Oberling, J; Ochsner, E; O'Dell, J; Oelker, E; Ogin, G H; Oh, J J; Oh, S H; Ohme, F; Oliver, M; Oppermann, P; Oram, Richard J; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Overmier, H; Owen, B J; Pai, A; Pai, S A; Palamos, J R; Palashov, O; Palomba, C; Pal-Singh, A; Pan, H; Pankow, C; Pannarale, F; Pant, B C; Paoletti, F; Paoli, A; Papa, M A; Paris, H R; Parker, W; Pascucci, D; Pasqualetti, A; Passaquieti, R; Passuello, D; Patricelli, B; Patrick, Z; Pearlstone, B L; Pedraza, M; Pedurand, R; Pekowsky, L; Pele, A; Penn, S; Perreca, A; Perri, L M; Phelps, M; Piccinni, O J; Pichot, M; Piergiovanni, F; Pierro, V; Pillant, G; Pinard, L; Pinto, I M; Pitkin, M; Poe, M; Poggiani, R; Popolizio, P; Post, A; Powell, J; Prasad, J; Pratt, J; Predoi, V; Prestegard, T; Price, L R; Prijatelj, M; Principe, M; Privitera, S; Prix, R; Prodi, G A; Prokhorov, L; Puncken, O; Punturo, M; Puppo, P; P"urrer, M; Qi, H; Qin, J; Qiu, S; Quetschke, V; Quintero, E A; Quitzow-James, R; Raab, F J; Rabeling, D S; Radkins, H; Raffai, P; Raja, S; Rajan, C; Rakhmanov, M; Rapagnani, P; Raymond, V; Razzano, M; Re, V; Read, J; Reed, C M; Regimbau, T; Rei, L; Reid, S; Reitze, D H; Rew, H; Reyes, S D; Ricci, F; Riles, K; Rizzo, M; Robertson, N A; Robie, R; Robinet, F; Rocchi, A; Rolland, L; Rollins, J G; Roma, V J; Romano, R; Romanov, G; Romie, J H; Rosi'nska, D; Rowan, S; R"udiger, A; Ruggi, P; Ryan, K; Sachdev, S; Sadecki, T; Sadeghian, L; Sakellariadou, M; Salconi, L; Saleem, M; Salemi, F; Samajdar, A; Sammut, L; Sanchez, E J; Sandberg, V; Sandeen, B; Sanders, J R; Sassolas, B; Sathyaprakash, B S; Saulson, P R; Sauter, O E S; Savage, R L; Sawadsky, A; Schale, P; Schilling, R; Schmidt, J; Schmidt, P; Schnabel, R; Schofield, R M S; Sch"onbeck, A; Schreiber, E; Schuette, D; Schutz, B F; Scott, J; Scott, S M; Sellers, D; Sengupta, A S; Sentenac, D; Sequino, V; Sergeev, A; Setyawati, Y; Shaddock, D A; Shaffer, T; Shahriar, M S; Shaltev, M; Shapiro, B; Shawhan, P; Sheperd, A; Shoemaker, D H; Shoemaker, D M; Siellez, K; Siemens, X; Sieniawska, M; Sigg, D; Silva, A D; Singer, A; Singer, L P; Singh, A; Singh, R; Singhal, A; Sintes, A M; Slagmolen, B J J; Smith, J R; Smith, N D; Smith, R J E; Son, E J; Sorazu, B; Sorrentino, F; Souradeep, T; Srivastava, A K; Staley, A; Steinke, M; Steinlechner, J; Steinlechner, S; Steinmeyer, D; Stephens, B C; Stone, R; Strain, K A; Straniero, N; Stratta, G; Strauss, N A; Strigin, S; Sturani, R; Stuver, A L; Summerscales, T Z; Sun, L; Sunil, S; Sutton, P J; Swinkels, B L; Szczepa'nczyk, M J; Tacca, M; Talukder, D; Tanner, D B; T'apai, M; Tarabrin, S P; Taracchini, A; Taylor, R; Theeg, T; Thirugnanasambandam, M P; Thomas, E G; Thomas, M; Thomas, P; Thorne, K A; Thrane, E; Tiwari, S; Tiwari, V; Tokmakov, K V; Toland, K; Tomlinson, C; Tonelli, M; Tornasi, Z; Torres, C V; Torrie, C I; T"oyr"a, D; Travasso, F; Traylor, G; Trifir`o, D; Tringali, M C; Trozzo, L; Tse, M; Turconi, M; Tuyenbayev, D; Ugolini, D; Unnikrishnan, C S; Urban, A L; Usman, S A; Vahlbruch, H; Vajente, G; Valdes, G; van Bakel, N; van Beuzekom, M; Brand, J F J van den; Broeck, C Van Den; Vander-Hyde, D C; van der Schaaf, L; van Heijningen, J V; van Veggel, A A; Vardaro, M; Vass, S; Vas'uth, M; Vaulin, R; Vecchio, A; Vedovato, G; Veitch, J; Veitch, P J; Venkateswara, K; Verkindt, D; Vetrano, F; Vicer'e, A; Vinciguerra, S; Vine, D J; Vinet, J -Y; Vitale, S; Vo, T; Vocca, H; Vorvick, C; Voss, D V; Vousden, W D; Vyatchanin, S P; Wade, A R; Wade, L E; Wade, M; Walker, M; Wallace, L; Walsh, S; Wang, G; Wang, H; Wang, M; Wang, X; Wang, Y; Ward, R L; Warner, J; Was, M; Weaver, B; Wei, L -W; Weinert, M; Weinstein, A J; Weiss, R; Wen, L; Wessels, P; Westphal, T; Wette, K; Whelan, J T; Whiting, B F; Williams, R D; Williamson, A R; Willis, J L; Willke, B; Wimmer, M H; Winkler, W; Wipf, C C; Wittel, H; Woan, G; Woehler, J; Worden, J; Wright, J L; Wu, D S; Wu, G; Yablon, J; Yam, W; Yamamoto, H; Yancey, C C; Yu, H; Yvert, M; zny, A Zadro; Zangrando, L; Zanolin, M; Zendri, J -P; Zevin, M; Zhang, L; Zhang, M; Zhang, Y; Zhao, C; Zhou, M; Zhou, Z; Zhu, X J; Zucker, M E; Zuraw, S E; Zweizig, J

    2016-01-01

    We report here the non-detection of gravitational waves from the merger of binary neutron star systems and neutron-star--black-hole systems during the first observing run of Advanced LIGO. In particular we searched for gravitational wave signals from binary neutron star systems with component masses $\\in [1,3] M_{\\odot}$ and component dimensionless spins $< 0.05$. We also searched for neutron-star--black-hole systems with the same neutron star parameters, black hole mass $\\in [2,99] M_{\\odot}$ and no restriction on the black hole spin magnitude. We assess the sensitivity of the two LIGO detectors to these systems, and find that they could have detected the merger of binary neutron star systems with component mass distributions of $1.35\\pm0.13 M_{\\odot}$ at a volume-weighted average distance of $\\sim$ 70Mpc, and for neutron-star--black-hole systems with neutron star masses of $1.4M_\\odot$ and black hole masses of at least $5M_\\odot$, a volume-weighted average distance of at least $\\sim$ 110Mpc. From this we...

  11. Advances of Bioinformatics Tools Applied in Virus Epitopes Prediction

    Institute of Scientific and Technical Information of China (English)

    Ping Chen; Simon Rayner; Kang-hong Hu

    2011-01-01

    In recent years, the in silico epitopes prediction tools have facilitated the progress of vaccines development significantly and many have been applied to predict epitopes in viruses successfully. Herein, a general overview of different tools currently available, including T cell and B cell epitopes prediction tools, is presented. And the principles of different prediction algorithms are reviewed briefly. Finally, several examples are present to illustrate the application of the prediction tools.

  12. Nonstandard Analysis Applied to Advanced Undergraduate Mathematics - Infinitesimal Modeling

    OpenAIRE

    Herrmann, Robert A.

    2003-01-01

    This is a Research and Instructional Development Project from the U. S. Naval Academy. In this monograph, the basic methods of nonstandard analysis for n-dimensional Euclidean spaces are presented. Specific rules are deveoped and these methods and rules are applied to rigorous integral and differential modeling. The topics include Robinson infinitesimals, limited and infinite numbers; convergence theory, continuity, *-transfer, internal definition, hyprefinite summation, Riemann-Stieltjes int...

  13. Editorial: Advances in Health Education Applying E-Learning, Simulations and Distance Technologies

    OpenAIRE

    Andre W. Kushniruk (ACMI Fellow; CAHS Fellow)

    2011-01-01

    This special issue of the KM&EL international journal is dedicated to coverage of novel advances in health professional education applying e-Learning, simulations and distance education technologies. Modern healthcare is beginning to be transformed through the emergence of new information technologies and rapid advances in health informatics. Advances such as electronic health record systems (EHRs), clinical decision support systems and other advanced information systems such as public health...

  14. Neutron Activation Analysis and High Resolution Gamma-Ray Spectrometry Applied to Areal Elemental Distribution Studies

    International Nuclear Information System (INIS)

    Schuiling (1967) applied both 'metallogenetic province' and continental drift principles to a study of the world-wide distribution of tin. A plot of tin deposit occurrences on the continents reconstituted as 'Pangeae' yielded 'tin belts' joining intercontinentally between the Americas, Africa and Europe. Discussions with Sir John Cockcroft and Sir Edward Bullard, in April 1967, led to this study of the applicability of automated, instrumental thermal neutron activation analysis techniques to large-scale areal elemental distribution determinations related to continental drift and to metallogenesis. The Enchanted Rock batholith, Llano, Texas, was selected as an initial area in which to apply this method on the basis of the availability of independent geochemical information concerning the pluton from Hutchinson (1956), Billings (1963) and Ragland (1968). Rock samples, including points from areas outside the batholith, were obtained at each of 16 sampling sites. One-gram rock samples were irradiated in a thermal neutron flux of ≈2 x 1012 n/cm2 s for 2 hours. Six trace elements (Hf, Ta, Co, Eu, Sc and La), and one minor element (Fe), were determined by gamma-ray spectrometry utilizing a 19 cm3 Ge(Li) detector and a 3200-channel analyser, and were areally mapped. The results indicate continuous trends in each trace element, through various rock types, over a distance of greater than 50 miles. The trace elements of pyrite, chalcopynte and sphalerite obtained from the Philippine Islands were measured in order to apply this procedure to minerals in a location where their areal extent has not previously been extensively studied. The methodology described above was repeated. A set of average element abundances in chalcopynte, pyrite and sphalerite is suggested on which to base the presence or absence of an element province or combined elements provinces. Preliminary results indicate the presence of a gold province in the northwestern part of Luzon Island. This technique

  15. From the similarities between neutrons and radon to advanced radon-detection and improved cold fusion neutron-measurements

    Science.gov (United States)

    Tommasino, L.; Espinosa, G.

    2014-07-01

    Neutrons and radon are both ubiquitous in the earth's crust. The neutrons of terrestrial origin are strongly related to radon since they originate mainly from the interactions between the alpha particles from the decays of radioactive-gas (namely Radon and Thoron) and the light nuclei. Since the early studies in the field of neutrons, the radon gas was used to produce neutrons by (α, n) reactions in beryllium. Another important similarity between radon and neutrons is that they can be detected only through the radiations produced respectively by decays or by nuclear reactions. These charged particles from the two distinct nuclear processes are often the same (namely alpha-particles). A typical neutron detector is based on a radiator facing a alpha-particle detector, such as in the case of a neutron film badge. Based on the similarity between neutrons and radon, a film badge for radon has been recently proposed. The radon film badge, in addition to be similar, may be even identical to the neutron film badge. For these reasons, neutron measurements can be easily affected by the presence of unpredictable large radon concentration. In several cold fusion experiments, the CR-39 plastic films (typically used in radon and neutron film-badges), have been the detectors of choice for measuring neutrons. In this paper, attempts will be made to prove that most of these neutron-measurements might have been affected by the presence of large radon concentrations.

  16. Advanced LIGO Constraints on Neutron Star Mergers and R-Process Sites

    CERN Document Server

    Côté, Benoit; Fryer, Chris L; Ritter, Christian; Paul, Adam; Wehmeyer, Benjamin; O'Shea, Brian W

    2016-01-01

    The role of compact binary mergers as the main production site of r-process elements is investigated by combining stellar abundances of Eu observed in the Milky Way, galactic chemical evolution (GCE) simulations, binary population synthesis models, and Advanced LIGO gravitational wave measurements. We compiled and reviewed seven recent GCE studies to extract the frequency of neutron star - neutron star (NS-NS) mergers that is needed in order to reproduce the observed [Eu/Fe] vs [Fe/H] relationship. We used our simple chemical evolution code to explore the impact of different analytical delay-time distribution (DTD) functions for NS-NS mergers. We then combined our metallicity-dependent population synthesis models with our chemical evolution code to bring their predictions, for both NS-NS mergers and black hole - neutron star mergers, into a GCE context. Finally, we convolved our results with the cosmic star formation history to provide a direct comparison with current and upcoming Advanced LIGO measurements. ...

  17. NATO Advanced Research Workshop on Fundamental and Applied Electromagnetics

    CERN Document Server

    Maksimenko, Sergey

    2016-01-01

    This book presents the most relevant and recent results in the study of “Nanoelectromagnetics”, a recently born fascinating research discipline, whose popularity is fast arising with the intensive penetration of nanotechnology in the world of electronics applications. Studying nanoelectromagnetics means describing the interaction between electromagnetic radiation and quantum mechanical low-dimensional systems: this requires a full interdisciplinary approach, the reason why this book hosts contributions from the fields of fundamental and applied electromagnetics, of chemistry and technology of nanostructures and nanocomposites, of physics of nano-structures systems, etc. The book is aimed at providing the reader with the state of the art in Nanoelectromagnetics, from theoretical modelling to experimental characterization, from design to synthesis, from DC to microwave and terahertz applications, from the study of fundamental material properties to the analysis of complex systems and devices, from commercia...

  18. Early Advanced LIGO binary neutron-star sky localization and parameter estimation

    CERN Document Server

    Berry, C P L; Farr, W M; Haster, C-J; Mandel, I; Middleton, H; Singer, L P; Urban, A L; Vecchio, A; Vitale, S; Cannon, K; Graff, P B; Hanna, C; Mohapatra, S; Pankow, C; Price, L R; Sidery, T; Veitch, J

    2016-01-01

    2015 will see the first observations of Advanced LIGO and the start of the gravitational-wave (GW) advanced-detector era. One of the most promising sources for ground-based GW detectors are binary neutron-star (BNS) coalescences. In order to use any detections for astrophysics, we must understand the capabilities of our parameter-estimation analysis. By simulating the GWs from an astrophysically motivated population of BNSs, we examine the accuracy of parameter inferences in the early advanced-detector era. We find that sky location, which is important for electromagnetic follow-up, can be determined rapidly (~5 s), but that sky areas may be hundreds of square degrees. The degeneracy between component mass and spin means there is significant uncertainty for measurements of the individual masses and spins; however, the chirp mass is well measured (typically better than 0.1%).

  19. AN ADVANCED TOOL FOR APPLIED INTEGRATED SAFETY MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Potts, T. Todd; Hylko, James M.; Douglas, Terence A.

    2003-02-27

    WESKEM, LLC's Environmental, Safety and Health (ES&H) Department had previously assessed that a lack of consistency, poor communication and using antiquated communication tools could result in varying operating practices, as well as a failure to capture and disseminate appropriate Integrated Safety Management (ISM) information. To address these issues, the ES&H Department established an Activity Hazard Review (AHR)/Activity Hazard Analysis (AHA) process for systematically identifying, assessing, and controlling hazards associated with project work activities during work planning and execution. Depending on the scope of a project, information from field walkdowns and table-top meetings are collected on an AHR form. The AHA then documents the potential failure and consequence scenarios for a particular hazard. Also, the AHA recommends whether the type of mitigation appears appropriate or whether additional controls should be implemented. Since the application is web based, the information is captured into a single system and organized according to the >200 work activities already recorded in the database. Using the streamlined AHA method improved cycle time from over four hours to an average of one hour, allowing more time to analyze unique hazards and develop appropriate controls. Also, the enhanced configuration control created a readily available AHA library to research and utilize along with standardizing hazard analysis and control selection across four separate work sites located in Kentucky and Tennessee. The AHR/AHA system provides an applied example of how the ISM concept evolved into a standardized field-deployed tool yielding considerable efficiency gains in project planning and resource utilization. Employee safety is preserved through detailed planning that now requires only a portion of the time previously necessary. The available resources can then be applied to implementing appropriate engineering, administrative and personal protective equipment

  20. Validation of multigroup neutron cross sections and calculational methods for the advanced neutron source against the FOEHN critical experiments measurements

    Energy Technology Data Exchange (ETDEWEB)

    Smith, L.A.; Gallmeier, F.X. [Oak Ridge Institute for Science and Energy, TN (United States); Gehin, J.C. [Oak Ridge National Lab., TN (United States)] [and others

    1995-05-01

    The FOEHN critical experiment was analyzed to validate the use of multigroup cross sections and Oak Ridge National Laboratory neutronics computer codes in the design of the Advanced Neutron Source. The ANSL-V 99-group master cross section library was used for all the calculations. Three different critical configurations were evaluated using the multigroup KENO Monte Carlo transport code, the multigroup DORT discrete ordinates transport code, and the multigroup diffusion theory code VENTURE. The simple configuration consists of only the fuel and control elements with the heavy water reflector. The intermediate configuration includes boron endplates at the upper and lower edges of the fuel element. The complex configuration includes both the boron endplates and components in the reflector. Cross sections were processed using modules from the AMPX system. Both 99-group and 20-group cross sections were created and used in two-dimensional models of the FOEHN experiment. KENO calculations were performed using both 99-group and 20-group cross sections. The DORT and VENTURE calculations were performed using 20-group cross sections. Because the simple and intermediate configurations are azimuthally symmetric, these configurations can be explicitly modeled in R-Z geometry. Since the reflector components cannot be modeled explicitly using the current versions of these codes, three reflector component homogenization schemes were developed and evaluated for the complex configuration. Power density distributions were calculated with KENO using 99-group cross sections and with DORT and VENTURE using 20-group cross sections. The average differences between the measured values and the values calculated with the different computer codes range from 2.45 to 5.74%. The maximum differences between the measured and calculated thermal flux values for the simple and intermediate configurations are {approx} 13%, while the average differences are < 8%.

  1. Applying Technology Ranking and Systems Engineering in Advanced Life Support

    Science.gov (United States)

    Jones, Harry; Luna, Bernadette (Technical Monitor)

    2000-01-01

    According to the Advanced Life Support (ALS) Program Plan, the Systems Modeling and Analysis Project (SMAP) has two important tasks: 1) prioritizing investments in ALS Research and Technology Development (R&TD), and 2) guiding the evolution of ALS systems. Investments could be prioritized simply by independently ranking different technologies, but we should also consider a technology's impact on system design. Guiding future ALS systems will require SMAP to consider many aspects of systems engineering. R&TD investments can be prioritized using familiar methods for ranking technology. The first step is gathering data on technology performance, safety, readiness level, and cost. Then the technologies are ranked using metrics or by decision analysis using net present economic value. The R&TD portfolio can be optimized to provide the maximum expected payoff in the face of uncertain future events. But more is needed. The optimum ALS system can not be designed simply by selecting the best technology for each predefined subsystem. Incorporating a new technology, such as food plants, can change the specifications of other subsystems, such as air regeneration. Systems must be designed top-down starting from system objectives, not bottom-up from selected technologies. The familiar top-down systems engineering process includes defining mission objectives, mission design, system specification, technology analysis, preliminary design, and detail design. Technology selection is only one part of systems analysis and engineering, and it is strongly related to the subsystem definitions. ALS systems should be designed using top-down systems engineering. R&TD technology selection should consider how the technology affects ALS system design. Technology ranking is useful but it is only a small part of systems engineering.

  2. Boron neutron capture therapy for advanced and/or recurrent cancers in the oral cavity

    International Nuclear Information System (INIS)

    This preliminary study of 5 patients with advanced and/or recurrent cancer in the oral cavity was performed to evaluate the effectiveness of Boron Neutron Capture Therapy (BNCT). The patients received therapy with the 10B-carrier p-boronophenylalanine (BPA) with or without borocaptate sodium (BSH) and irradiation thereafter with epithermal neutrons. All underwent 18F-BPA PET studies before receiving BNCT to determine the accumulation ratios of BPA in tumor and normal tissues. The tumor mass was decreased in size and at minimum a transient partial response was achieved in all cases, though rapid tumor re-growth was observed in 2. Although tentative clinical responses and improvements in quality of life were recognized, obliteration of the tumor was not obtained in any of the cases. Additional studies are required to determine the utility and indication of BNCT for oral cancer. (author)

  3. Optimization of a neutron transmission beamline applied to materials science for the CAB linear accelerator

    International Nuclear Information System (INIS)

    The Neutrons and Reactors Laboratory (NYR) of CAB (Centro Atomico Bariloche) is equipped with a linear electron accelerator (LINAC - Linear particle accelerator). This LINAC is used as a neutron source from which two beams are extracted to perform neutron transmission and dispersion experiments. Through these experiments, structural and dynamic properties of materials can be studied. The neutron transmission experiments consist in a collimated neutron beam which interacts with a sample and a detector behind the sample. Important information about the microstructural characteristics of the material can be obtained from the comparison between neutron spectra before and after the interaction with the sample. In the NYR Laboratory, cylindrical samples of one inch of diameter have been traditionally studied. Nonetheless, there is a great motivation for doing systematic research on smaller and with different geometries samples; particularly sheets and samples for tensile tests. Hence, in the NYR Laboratory it has been considered the possibility of incorporating a neutron guide into the existent transmission line. According to all mentioned above, the main objective of this work consisted in the optimization of the flight transmission tube optics of neutrons. This optimization not only improved the existent line but also contributed to an election criterion for the neutron guide acquisition.

  4. Phase Transition Mapping by Means of Neutron Imaging in SOFC Anode Supports During Reduction Under Applied Stress

    DEFF Research Database (Denmark)

    Makowska, Malgorzata; Strobl, M.; Lauridsen, E. M.;

    2015-01-01

    crucial for optimization of the SOC performance. In this work the measurements with energy resolved neutron imaging of the phase transition during the NiOYSZ reduction performed at different temperatures with and without applied load, are presented. The results indicate a link between reduction rate and...

  5. A new mixed discontinuous finite element formulation applied to neutron diffusion problems; Nova formulacao mista em elementos finitos discontinuos aplicada a problemas de difusao de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Monica Barcellos Jansen; Carmo, Eduardo Gomes Dutra do [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear. E-mail: monica@lmn.com.ufrj.br; carmo@lmn.com.ufrj.br

    2000-07-01

    In this work, a new mixed discontinuous finite element formulation is applied to the solution of neutron diffusion problems posed in a heterogeneous section of a reactor, taking account of two energy groups. Numerical results of a model problem are presented herein, which demonstrate the efficiency of the method and the little mesh refinement necessary for a good approximation. The above-mentioned formulation has terms that guarantee its stability even without to use of the LBB (Ladyzhesnkaya-Babuska-Brezzi) condition. (author)

  6. The Saudi experience with neutron therapy in locally advanced head and neck cancers

    International Nuclear Information System (INIS)

    The neutron therapy program at King Faisal Specialist Hospital and Research Center conducted a phase II study to evaluate the toxicity and efficacy of neutrons against conventional external megavoltage irradiation in patients with locally advanced head and neck malignancy. One hundred and nineteen patients were allocated to receive either photons (46/119) or neutrons (73/119). Radiation effects were scored according to the EORTC/RTOG criteria; data was collected weekly during treatment, once a month for the first year and at 6-month intervals subsequently. While acute effects were scored in all patients, only 59 were evaluable for late effects and locoregional control. A composite of the average reaction results were obtained using this information, to compare them in time, for acute and late effects in both arms of the study. The maximum acute reactions in the two groups were similar. In the majority of the patients (80 %) acute skin and mucosal reactions occurred during the last week of treatment. The changes in the subcutaneous tissues and salivary glands became clinically apparent at 3 months or later. Salivary gland toxicity was more severe in the photon arm and the difference was statistically significant at 3 months (P + 0.04) but this was lost at 12 months. Late effects for skin and subcutaneous tissues were significantly more severe in the neutron arm with P values of 0.04 and 0.01 respectively. Three patients in the neutron arm died of grade 4 radiation complications. The local control and survival were similar in both groups. (author)

  7. Neutron cross-sections for advanced nuclear systems. The nTOF project at CERN

    International Nuclear Information System (INIS)

    In 2012, nuclear energy continued to play an important role in global electricity production. Despite a small reduction of the total generating nuclear power capacity after the accident at the Fukushima Daiichi nuclear power plant, a significant growth, between 35% and 100% by 2030, is foreseen in the use of nuclear energy worldwide. The knowledge of a wide variety of nuclear processes is a fundamental prerequisite in nuclear technology, as well as in other field of fundamental and applied Nuclear Physics. In particular, neutron-induced reactions play a key role in the operation of present nuclear reactors as well as in the design of future ones aiming at minimizing nuclear waste, such as Generation-IV reactors, ADS or reactors based on Th/U fuel cycle. The cross sections of a large number of neutron-induced reactions are requested with high accuracy to improve safety and efficiency of current reactors, and for the design of future generation systems. Since 2001 nTOF, an innovative neutron Time-Of-Flight facility, has been operating at CERN with the aim of addressing the needs of nuclear data for basic and applied nuclear Physics. An extensive program on both neutron induced fission and capture reactions has been carried out so far. Thanks to the well suited features of the nTOF neutron beam, such as the high instantaneous neutron flux, the high resolution and the wide energy range covered, from thermal to a few GeV, coupled with state-of-the-art detectors and data acquisition system, it has been possible to collect high accuracy and high resolution neutron cross-section data on a variety of isotopes, many of which radioactive. In particular, important results for nuclear technologies have been obtained on isotopes of U, Pu and minor actinides with long half life. Recently the construction of a new, high-flux measuring station has started. A 25 times higher fluence relative to the existing experimental area will allow to measure isotopes with short half life, as

  8. Advanced Signal Processing Methods Applied to Digital Mammography

    Science.gov (United States)

    Stauduhar, Richard P.

    1997-01-01

    without further support. Task 5: Better modeling does indeed make an improvement in the detection output. After the proposal ended, we came up with some new theoretical explanations that helps in understanding when the D4 filter should be better. This work is currently in the review process. Task 6: N/A. This no longer applies in view of Tasks 4-5. Task 7: Comprehensive plans for further work have been completed. These plans are the subject of two proposals, one to NASA and one to HHS. These proposals represent plans for a complete evaluation of the methods for identifying normal mammograms, augmented with significant further theoretical work.

  9. Experimental characterization of the Advanced Liquid Hydrogen Cold Neutron Source spectrum of the NBSR reactor at the NIST Center for Neutron Research

    Science.gov (United States)

    Cook, J. C.; Barker, J. G.; Rowe, J. M.; Williams, R. E.; Gagnon, C.; Lindstrom, R. M.; Ibberson, R. M.; Neumann, D. A.

    2015-08-01

    The recent expansion of the National Institute of Standards and Technology (NIST) Center for Neutron Research facility has offered a rare opportunity to perform an accurate measurement of the cold neutron spectrum at the exit of a newly-installed neutron guide. Using a combination of a neutron time-of-flight measurement, a gold foil activation measurement, and Monte Carlo simulation of the neutron guide transmission, we obtain the most reliable experimental characterization of the Advanced Liquid Hydrogen Cold Neutron Source brightness to date. Time-of-flight measurements were performed at three distinct fuel burnup intervals, including one immediately following reactor startup. Prior to the latter measurement, the hydrogen was maintained in a liquefied state for an extended period in an attempt to observe an initial radiation-induced increase of the ortho (o)-hydrogen fraction. Since para (p)-hydrogen has a small scattering cross-section for neutron energies below 15 meV (neutron wavelengths greater than about 2.3 Å), changes in the o- p hydrogen ratio and in the void distribution in the boiling hydrogen influence the spectral distribution. The nature of such changes is simulated with a continuous-energy, Monte Carlo radiation-transport code using 20 K o and p hydrogen scattering kernels and an estimated hydrogen density distribution derived from an analysis of localized heat loads. A comparison of the transport calculations with the mean brightness function resulting from the three measurements suggests an overall o- p ratio of about 17.5(±1) % o- 82.5% p for neutron energies<15 meV, a significantly lower ortho concentration than previously assumed.

  10. Follow-up fuel plate stability experiments and analyses for the Advanced Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Swinson, W.F.; Battiste, R.L.; Luttrell, C.R.; Yahr, G.T.

    1993-11-01

    The reactor for the planned Advanced Neutron Source uses closely spaced plates cooled by heavy water flowing through narrow channels. Two sets of tests were performed on the upper and lower fuel plates for the structural response of the fuel plates to the required high coolant flow velocities. This report contains the data from the second round of tests. Results and conclusions from all of the tests are also included in this report. The tests were done using light water on full-scale epoxy models, and through model theory, the results were related to the prototype plates, which are aluminum-clad aluminum/uranium silicide involute-shaped plates.

  11. Initial global 2-D shielding analysis for the Advanced Neutron Source core and reflector

    Energy Technology Data Exchange (ETDEWEB)

    Bucholz, J.A.

    1995-08-01

    This document describes the initial global 2-D shielding analyses for the Advanced Neutron Source (ANS) reactor, the D{sub 2}O reflector, the reflector vessel, and the first 200 mm of light water beyond the reflector vessel. Flux files generated here will later serve as source terms in subsequent shielding analyses. In addition to reporting fluxes and other data at key points of interest, a major objective of this report was to document how these analyses were performed, the phenomena that were included, and checks that were made to verify that these phenomena were properly modeled. In these shielding analyses, the fixed neutron source distribution in the core was based on the `lifetime-averaged` spatial power distribution. Secondary gamma production cross sections in the fuel were modified so as to account intrinsically for delayed fission gammas in the fuel as well as prompt fission gammas. In and near the fuel, this increased the low-energy gamma fluxes by 50 to 250%, but out near the reflector vessel, these same fluxes changed by only a few percent. Sensitivity studies with respect to mesh size were performed, and a new 2-D mesh distribution developed after some problems were discovered with respect to the use of numerous elongated mesh cells in the reflector. All of the shielding analyses were performed sing the ANSL-V 39n/44g coupled library with 25 thermal neutron groups in order to obtain a rigorous representation of the thermal neutron spectrum throughout the reflector. Because of upscatter in the heavy water, convergence was very slow. Ultimately, the fission cross section in the various materials had to be artificially modified in order to solve this fixed source problem as an eigenvalue problem and invoke the Vondy error-mode extrapolation technique which greatly accelerated convergence in the large 2-D RZ DORT analyses. While this was quite effective, 150 outer iterations (over energy) were still required.

  12. Neutronics methods, models, and applications at the Idaho National Engineering Laboratory for the advanced neutron source reactor three-element core design

    International Nuclear Information System (INIS)

    A summary of the methods and models used to perform neutronics analyses on the Advanced Neutron Source reactor three-element core design is presented. The applications of the neutral particle Monte Carlo code MCNP are detailed, as well as the expansion of the static role of MCNP to analysis of fuel cycle depletion calculations. Results to date of these applications are presented also. A summary of the calculations not yet performed is also given to provide a open-quotes to-doclose quotes list if the project is resurrected

  13. Inelastic neutron scattering applied to the investigation of collective excitations in topologically disordered matter

    Directory of Open Access Journals (Sweden)

    J.-B.Suck

    2008-03-01

    Full Text Available Inelastic neutron scattering techniques are introduced here as one of the most important experimental techniques in the investigation of collective excitations in fluids (liquids and compressed gases and amorphous solids. The correlation functions involved, the spectra of which are determined in inelastic neutron scattering experiments, the dispersion relations of the collective excitations and how they are obtained from the measured spectra and finally two of the most often used instrumental techniques are briefly discussed.

  14. The EU power plant conceptual study - neutronic design analyses for near term and advanced reactor models

    International Nuclear Information System (INIS)

    A power plant conceptual study (PPCS) has been conducted in the framework of the European fusion programme with the main objective to demonstrate the safety and environmental advantages and the economic viability of fusion power. Power plant models with limited (''near term concepts'') and advanced plasma physics and technological extrapolations (''advanced concepts'') were considered. Two near term plant models were selected, one employing a water cooled lithium-lead (WCLL), and the other one a helium cooled pebble bed (HCPB) blanket. Two variants were also considered for the advanced power plant models, one adopting a liquid metal blanket with a self-cooled lithium-lead breeder zone and a helium cooled steel structure (''dual coolant lithium lead'', DCLL), and the other one a self-cooled lithium-lead (SCLL) blanket with SiCf/SiC composite as structural material. This report provides a detailed documentation of the neutronics design analyses performed as part of the PPCS study for both the near term and advanced power plant models. Main issues are the assessment of the tritium breeding capability, the evaluation of the nuclear power generation and its spatial distribution, and the assessment and optimisation of the shielding performance. The analyses were based on three-dimensional Monte Carlo calculations with the MCNP code using suitable torus sector models developed for the different PPCS plant variants. (orig.)

  15. Neutronic Analysis of Advanced SFR Burner Cores using Deep-Burn PWR Spent Fuel TRU Feed

    International Nuclear Information System (INIS)

    In this work, an advanced sodium-cooled fast TRU (Transuranics) burner core using deep-burn TRU feed composition discharged from small LWR cores was neutronically analyzed to show the effects of deeply burned TRU feed composition on the performances of sodium-cooled fast burner core. We consider a nuclear park that is comprised of the commercial PWRs, small PWRs of 100MWe for TRU deep burning using FCM (Fully Ceramic Micro-encapsulated) fuels and advanced sodium-cooled fast burners for their synergistic combination for effective TRU burning. In the small PWR core having long cycle length of 4.0 EFPYs, deep burning of TRU up to 35% is achieved with FCM fuel pins whose TRISO particle fuels contain TRUs in their central kernel. In this paper, we analyzed the performances of the advanced SFR burner cores using TRU feeds discharged from the small long cycle PWR deep-burn cores. Also, we analyzed the effect of cooling time for the TRU feeds on the SFR burner core. The results showed that the TRU feed composition from FCM fuel pins of the small long cycle PWR core can be effectively used into the advanced SFR burner core by significantly reducing the burnup reactivity swing which reduces smaller number of control rod assemblies to satisfy all the conditions for the self controllability than the TRU feed composition discharged from the typical PWR cores

  16. Advanced liquid and solid extraction procedures for ultratrace determination of rhenium by radiochemical neutron activation analysis

    Science.gov (United States)

    Mizera, J.; Kučera, J.; Řanda, Z.; Lučaníková, M.

    2006-01-01

    Radiochemical neutron activation analysis (RNAA) procedures for determination of Re at the ultratrace level based on use of liquid-liquid extraction (LLE) and extraction chromatography (EXC) have been developed. Two different LLE procedures were used depending on the way of sample decomposition using either 2-butanone or tetraphenylarsonium chloride in CHCl3. EXC employed new solid extractant materials prepared by incorporation of the liquid trioctyl-methyl-ammonium chloride into an inert polyacrylonitrile matrix. The RNAA procedures presented have been compared and applied for Re determination in several biological and environmental reference materials.

  17. Dipolar structures in magnetite ferrofluids studied with small-angle neutron scattering with and without applied magnetic field

    OpenAIRE

    Klokkenburg, M.; Erne, B.H.; Wiedenmann, A.; Petukhov, A.V.; Philipse, A. P.

    2007-01-01

    Field-induced structure formation in a ferrofluid with well-defined magnetite nanoparticles with a permanent magnetic dipole moment was studied with small-angle neutron scattering (SANS) as a function of the magnetic interactions. The interactions were tuned by adjusting the size of the well-defined, single-magnetic-domain magnetite (Fe3O4) particles and by applying an external magnetic field. For decreasing particle dipole moments, the data show a progressive distortion of the hexagonal symm...

  18. Neutron tomography as a reverse engineering method applied to the IS-60 Rover gas turbine

    International Nuclear Information System (INIS)

    Probably the most common method of reverse engineering in mechanical engineering involves measuring the physical geometry of a component using a coordinate measuring machine (CMM). Neutron tomography, in contrast, is used primarily as a non-destructive testing technique. This paper, however, explores the use of this technique in its tomographic application (neutron CAT scanning mode) as a reverse engineering tool, particularly for complex internal geometries, as it has the added advantage of being a non-destructive and non-invasive method. Several components from an IS-60 Rover gas turbine were scanned using neutron tomography and through the analyses it was demonstrated that the technique may be promising for reverse engineering purposes.

  19. ADVANCED OXIDATION PROCESSES (AOPs) APPLIED FOR WASTEWATER AND DRINKING WATER TREATMENT. ELIMINATION OF PHARMACEUTICALS

    OpenAIRE

    Petrovic, Mira; Radjenovic, Jelena; Barcelo, Damia

    2011-01-01

    Due to their insufficient removal in conventional wastewater treatments, advanced drinking and wastewater treatment options should be considered for the removal of pharmaceutically active compounds (PhACs) from urban, hospital and industrial wastewaters. This paper summarizes the current state-of-the-art in two often applied advanced oxidation processes (AOPs), namely TiO2 assisted photocatalysis and photo-Fenton process. Their possibilities in removing PhACs are discussed, giving examples fo...

  20. Advanced Neutron Source enrichment study. Volume 2: Appendices -- Final report, Revision 12/94

    International Nuclear Information System (INIS)

    A study has been performed of the impact on performance of using low enriched uranium (20% 235U) or medium enriched uranium (35% 235U) as an alternative fuel for the Advanced Neutron Source, which is currently designed to use uranium enriched to 93% 235U. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in terms of impact on neutron flux, safety, safeguards, technical feasibility, and cost. The feasibility of fabricating uranium silicide fuel at increasing material density was specifically addressed by a panel of international experts on research reactor fuels. The most viable alternative designs for the reactor at lower enrichments were identified and discussed. Several sensitivity analyses were performed to gain an understanding of the performance of the reactor at parametric values of power, fuel density, core volume, and enrichment that were interpolations between the boundary values imposed on the study or extrapolations from known technology. Volume 2 of this report contains 26 appendices containing results, meeting minutes, and fuel panel presentations. There are 26 appendices in this volume

  1. NATO Advanced Study Institute on Chemical Crystallography with Pulsed Neutrons and Synchrotron X-Rays

    CERN Document Server

    Jeffrey, George

    1988-01-01

    X-ray and neutron crystallography have played an increasingly impor­ tant role in the chemical and biochemical sciences over the past fifty years. The principal obstacles in this methodology, the phase problem and com­ puting, have been overcome. The former by the methods developed in the 1960's and just recognised by the 1985 Chemistry Nobel Prize award to Karle and Hauptman, the latter by the dramatic advances that have taken place in computer technology in the past twenty years. Within the last decade, two new radiation sources have been added to the crystallographer's tools. One is synchrotron X-rays and the other is spallation neutrons. Both have much more powerful fluxes than the pre­ vious sources and they are pulsed rather than continuos. New techniques are necessary to fully exploit the intense continuos radiation spectrum and its pulsed property. Both radiations are only available from particular National Laboratories on a guest-user basis for scientists outside these Na­ tional Laboratories. Hi...

  2. Steady-state thermal-hydraulic design analysis of the Advanced Neutron Source reactor

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) is a research reactor that is planned for construction at Oak Ridge National Laboratory. This reactor will be a user facility with the major objective of providing the highest continuous neutron beam intensities of any reactor in the world. Additional objectives for the facility include providing materials irradiation facilities and isotope production facilities as good as, or better than, those in the High Flux Isotope Reactor. To achieve these objectives, the reactor design uses highly subcooled heavy water as both coolant and moderator. Two separate core halves of 67.6-L total volume operate at an average power density of 4.5 MW(t)/L, and the coolant flows upward through the core at 25 m/s. Operating pressure is 3.1 MPa at the core inlet with a 1.4-MPa pressure drop through the core region. Finally, in order to make the resources available for experimentation, the fuel is designed to provide a 17-d fuel cycle with an additional 4 d planned in each cycle for the refueling process. This report examines the codes and models used to develop the thermal-hydraulic design for ANS, as well as the correlations and physical data; evaluates thermal-hydraulic uncertainties; reports on thermal-hydraulic design and safety analysis; describes experimentation in support of the ANS reactor design and safety analysis; and provides an overview of the experimental plan

  3. Review and Assessment of Neutron Cross Section and Nubar Covariances for Advanced Reactor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Maslov,V.M.; Oblozinsky, P.; Herman, M.

    2008-12-01

    In January 2007, the National Nuclear Data Center (NNDC) produced a set of preliminary neutron covariance data for the international project 'Nuclear Data Needs for Advanced Reactor Systems'. The project was sponsored by the OECD Nuclear Energy Agency (NEA), Paris, under the Subgroup 26 of the International Working Party on Evaluation Cooperation (WPEC). These preliminary covariances are described in two recent BNL reports. The NNDC used a simplified version of the method developed by BNL and LANL that combines the recent Atlas of Neutron Resonances, the nuclear reaction model code EMPIRE and the Bayesian code KALMAN with the experimental data used as guidance. There are numerous issues involved in these estimates of covariances and it was decided to perform an independent review and assessment of these results so that better covariances can be produced for the revised version in future. Reviewed and assessed are uncertainties for fission, capture, elastic scattering, inelastic scattering and (n,2n) cross sections as well as prompt nubars for 15 minor actinides ({sup 233,234,236}U, {sup 237}Np, {sup 238,240,241,242}Pu, {sup 241,242m,243}Am and {sup 242,243,244,245}Cm) and 4 major actinides ({sup 232}Th, {sup 235,238}U and {sup 239}Pu). We examined available evaluations, performed comparison with experimental data, taken into account uncertainties in model parameterization and made use state-of-the-art nuclear reaction theory to produce the uncertainty assessment.

  4. Analysis of coupled neutron-gamma radiations by the multigroup Albedo method applied to multilayered slab shieldings

    International Nuclear Information System (INIS)

    Full text: The principal nuclear design tools available to the shielding designer include diffusion approximation, transport theory, and Monte Carlo techniques. Full transport theory or Monte Carlo methods are routinely used for shielding analyses, where penetration investigations are more sensitive to directional aspects. However, the aim of this paper is to illustrate the coupled neutron-gamma Albedo method particularly as applied to problems of shielding analysis. The multigroup Albedo method is applied to coupled neutron-gamma radiations considering 'n' neutron energy groups and 'g' gamma energy groups to estimate the probabilities of transmission through, absorption in, and reflection from shieldings composed by multiple material layers, 'm' slabs, in which no fission occurs. In this study, these energy groups were selected in order to minimize upscattering effects of the radiation from lower energy groups to higher energy groups. However, neutrons of all energies are assumed to generate gammas of all energies. The reflection coefficient or Albedo is defined as the current of the reflected radiation divided by the incident radiation current. The absorption coefficient is defined as the rate at which radiation is lost by absorption per second divided by the amount of incident radiation per second. The transmission coefficient is defined as the current of the transmitted radiation divided by the incident radiation current. The interaction probabilities can be arranged in matrix form where the rows indicate the energy group of the incident radiation and the columns indicate the energy group of the radiation after interaction. Thus, each material has 3 sets of distinct matrices, for the interactions neutron-neutron (N-N), neutron-gamma (N-G) and gamma-gamma (G-G). Each set is composed by 3 matrices, giving a total of 9 matrices per material. The first matrix set is for scattering/downscattering of neutrons (N-N); the next set is for scattering/downscattering of

  5. Bayesian Statistical Analysis Applied to NAA Data for Neutron Flux Spectrum Determination

    Science.gov (United States)

    Chiesa, D.; Previtali, E.; Sisti, M.

    2014-04-01

    In this paper, we present a statistical method, based on Bayesian statistics, to evaluate the neutron flux spectrum from the activation data of different isotopes. The experimental data were acquired during a neutron activation analysis (NAA) experiment [A. Borio di Tigliole et al., Absolute flux measurement by NAA at the Pavia University TRIGA Mark II reactor facilities, ENC 2012 - Transactions Research Reactors, ISBN 978-92-95064-14-0, 22 (2012)] performed at the TRIGA Mark II reactor of Pavia University (Italy). In order to evaluate the neutron flux spectrum, subdivided in energy groups, we must solve a system of linear equations containing the grouped cross sections and the activation rate data. We solve this problem with Bayesian statistical analysis, including the uncertainties of the coefficients and the a priori information about the neutron flux. A program for the analysis of Bayesian hierarchical models, based on Markov Chain Monte Carlo (MCMC) simulations, is used to define the problem statistical model and solve it. The energy group fluxes and their uncertainties are then determined with great accuracy and the correlations between the groups are analyzed. Finally, the dependence of the results on the prior distribution choice and on the group cross section data is investigated to confirm the reliability of the analysis.

  6. Advancements in the development of a directional-position sensing fast neutron detector using acoustically tensioned metastable fluids

    Science.gov (United States)

    Archambault, Brian C.; Webster, Jeffrey A.; Grimes, Thomas F.; Fischer, Kevin F.; Hagen, Alex R.; Taleyakhan, Rusi P.

    2015-06-01

    Advancements in the development of a direction and position sensing fast neutron detector which utilizes the directional acoustic tensioned metastable fluid detector (D-ATMFD) are described. The resulting D-ATMFD sensor is capable of determining the direction of neutron radiation with a single compact detector versus use of arrays of detectors in conventional directional systems. Directional neutron detection and source positioning offer enhanced detection speeds in comparison to traditional proximity searching; including enabling determination of the neutron source shape, size, and strength in near real time. This paper discusses advancements that provide the accuracy and precision of ascertaining directionality and source localization information utilizing enhanced signal processing-cum-signal analysis, refined computational algorithms, and on-demand enlargement capability of the detector sensitive volume. These advancements were accomplished utilizing experimentation and theoretical modeling. Benchmarking and qualifications studies were successfully conducted with random and fission based special nuclear material (SNM) neutron sources (239Pu-Be and 252Cf). These results of assessments have indicated that the D-ATMFD compares well in technical performance with banks of competing directional fast neutron detector technologies under development worldwide, but it does so with a single detector unit, an unlimited field of view, and at a significant reduction in both cost and size while remaining completely blind to common background (e.g., beta-gamma) radiation. Rapid and direct SNM neutron source imaging with two D-ATMFD sensors was experimentally demonstrated, and furthermore, validated via multidimensional nuclear particle transport simulations utilizing MCNP-PoliMi. Characterization of a scaled D-ATMFD based radiation portal monitor (RPM) as a cost-effective and efficient 3He sensor replacement was performed utilizing MCNP-PoliMi simulations, the results of which

  7. Advancements in the development of a directional-position sensing fast neutron detector using acoustically tensioned metastable fluids

    International Nuclear Information System (INIS)

    Advancements in the development of a direction and position sensing fast neutron detector which utilizes the directional acoustic tensioned metastable fluid detector (D-ATMFD) are described. The resulting D-ATMFD sensor is capable of determining the direction of neutron radiation with a single compact detector versus use of arrays of detectors in conventional directional systems. Directional neutron detection and source positioning offer enhanced detection speeds in comparison to traditional proximity searching; including enabling determination of the neutron source shape, size, and strength in near real time. This paper discusses advancements that provide the accuracy and precision of ascertaining directionality and source localization information utilizing enhanced signal processing-cum-signal analysis, refined computational algorithms, and on-demand enlargement capability of the detector sensitive volume. These advancements were accomplished utilizing experimentation and theoretical modeling. Benchmarking and qualifications studies were successfully conducted with random and fission based special nuclear material (SNM) neutron sources (239Pu–Be and 252Cf). These results of assessments have indicated that the D-ATMFD compares well in technical performance with banks of competing directional fast neutron detector technologies under development worldwide, but it does so with a single detector unit, an unlimited field of view, and at a significant reduction in both cost and size while remaining completely blind to common background (e.g., beta-gamma) radiation. Rapid and direct SNM neutron source imaging with two D-ATMFD sensors was experimentally demonstrated, and furthermore, validated via multidimensional nuclear particle transport simulations utilizing MCNP-PoliMi. Characterization of a scaled D-ATMFD based radiation portal monitor (RPM) as a cost-effective and efficient 3He sensor replacement was performed utilizing MCNP-PoliMi simulations, the results of

  8. Practical application of passive safety features for the advanced neutron source cooling system

    International Nuclear Information System (INIS)

    The results of a conceptual design study leading to the definition of a reference design for the Advanced Neutron Source (ANS) heavy water cooling system are presented. The objective of this study was to define a cooling system that not only met the ANS goals for operating parameters, reliability, availability, and maintainability, but also used inherent, passive, and diverse features and characteristics to satisfy the ANS internal events core melt goal of -5/yr. The approach taken in this study was to define a cooling system configuration having the minimum basic components and characteristics to satisfy the requirements for normal operation, and then to add only those features necessary to meet the requirements for all emergency design-basis events

  9. Report of the advanced neutron source (ANS) aluminum cladding corrosion workshop

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) Corrosion Workshop on aluminum cladding corrosion in reactor environments is summarized. The Workshop was held to examine the aluminum cladding oxidation studies being conducted in support of the ANS design. This report was written principally to provide a record of the ideas and judgments expressed by the workshop attendees. The ANS operating heat flux is significantly higher than that in existing reactors, and early experiments indicate that there may be an aluminum cladding oxidation problem unique to higher heat fluxes or associated cladding temperatures that, if not solved, may limit the operation of the ANS to unacceptably low power levels. A brief description of the information presented by each speaker is included along with a compilation of the most significant ideas and recommended research areas. The appendixes contain a copy of the workshop agenda and a list of attendees

  10. Containment performance analyses for the Advanced Neutron Source Reactor at the Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.H.; Taleyarkhan, R.P.; Georgevich, V.

    1992-10-01

    This paper discusses salient aspects of methodology, assumptions, and modeling of various features related to estimation of source terms from two conservatively scoped severe accident scenarios in the Advanced Neutron Source (ANS) reactor at the Oak Ridge National Laboratory. Various containment configurations are considered for steaming-pool-type accidents and an accident involving molten core-concrete interaction. Several design features (such as rupture disks) are examined to study containment response during postulated severe accidents. Also, thermal-hydraulic response of the containment and radionuclide transport and retention in the containment are studied. The results are described as transient variations of source terms for each scenario, which are to be used for studying off-site radiological consequences and health effects for these postulated severe accidents. Also highlighted will be a comparison of source terms estimated by two different versions of the MELCOR code.

  11. Condensed matter and materials research using neutron diffraction and spectroscopy: reactor and pulsed neutron sources

    International Nuclear Information System (INIS)

    The paper provides a short, and partial view of the neutron scattering technique applied to condensed matter and materials research. Reactor and accelerator-based neutron spectrometers are discussed, together with examples of research projects that illustrate the puissance and modern applications of neutron scattering. Some examples are chosen to show the range of facilities available at the medium flux reactor operated by Casaccia ENEA, Roma and the advanced, pulsed spallation neutron source at the Rutherford Appleton Laboratory, Oxfordshire. (author)

  12. Validation of neutronic methods applied to the analysis of fast subcritical systems. The MUSE-2 experiments

    International Nuclear Information System (INIS)

    In the framework of the French SPIN program devoted to the separation and the transmutation of radioactive wastes, the CEA has launched the ISAAC program to investigate the potential of accelerator-driven systems and to provide an experimental validation of the physics characteristics of these systems. The neutronics of the subcritical core needs experimental validation. This can be done by decoupling the problem of the neutron source from the problem of the subcritical medium. Experiments with a well known external source placed in a subcritical medium have been performed in the MASURCA facility. The results confirm the high accuracy achievable with such experiments and the good quality of the ERANOS code system predictions. (author)

  13. Validation of neutronic methods applied to the analysis of fast subcritical systems. The MUSE-2 experiments

    Energy Technology Data Exchange (ETDEWEB)

    Soule, R.; Salvatores, M.; Jacqmin, R.; Martini, M.; Lebrat, J.F.; Bertrand, P. [CEA Centre d`Etudes de Cadarache, Service de Physique des Reacteurs et du Cycle, 13 - Saint-Paul-lez-Durance (France); Broccoli, U.; Peluso, V.

    1997-12-31

    In the framework of the French SPIN program devoted to the separation and the transmutation of radioactive wastes, the CEA has launched the ISAAC program to investigate the potential of accelerator-driven systems and to provide an experimental validation of the physics characteristics of these systems. The neutronics of the subcritical core needs experimental validation. This can be done by decoupling the problem of the neutron source from the problem of the subcritical medium. Experiments with a well known external source placed in a subcritical medium have been performed in the MASURCA facility. The results confirm the high accuracy achievable with such experiments and the good quality of the ERANOS code system predictions. (author)

  14. Neutron activation analysis as applied to instrumental analysis of trace elements from seawater

    International Nuclear Information System (INIS)

    Particulate matter collected from the coastal area delimited by the mouth of the river Volturno and the Sabaudia lake has been analyzed by instrumental neutron activation analysis for its content of twenty-two trace elements. The results for surface water and bottom water are reported separately, thus evidencing the effect of sampling depth on the concentration of many elements. The necessity of accurately 'cleaning' the filters before use is stressed

  15. Parameter estimation for binary neutron-star coalescences with realistic noise during the Advanced LIGO era

    CERN Document Server

    Berry, Christopher P L; Middleton, Hannah; Singer, Leo P; Urban, Alex L; Vecchio, Alberto; Vitale, Salvatore; Cannon, Kipp; Farr, Ben; Farr, Will M; Graff, Philip B; Hanna, Chad; Haster, Carl-Johan; Mohapatra, Satya; Pankow, Chris; Price, Larry R; Sidery, Trevor; Veitch, John

    2014-01-01

    Advanced ground-based gravitational-wave (GW) detectors begin operation imminently. Their intended goal is not only to make the first direct detection of GWs, but also to make inferences about the source systems. Binary neutron-star mergers are among the most promising sources. We investigate the performance of the parameter-estimation pipeline that will be used during the first observing run of the Advanced Laser Interferometer Gravitational-wave Observatory (aLIGO) in 2015: we concentrate on the ability to reconstruct the source location on the sky, but also consider the ability to measure masses and the distance. Accurate, rapid sky-localization is necessary to alert electromagnetic (EM) observatories so that they can perform follow-up searches for counterpart transient events. We consider parameter-estimation accuracy in the presence of realistic, non-Gaussian noise. We find that the character of the noise makes negligible difference to the parameter-estimation performance. The source luminosity distance ...

  16. 6.3 MeV fast neutrons in the treatment of patients with locally advanced and locally recurrent breast cancer

    Science.gov (United States)

    Velikaya, V. V.; Musabaeva, L. I.; Lisin, V. A.; Startseva, Zh. A.

    2016-08-01

    The study included 135 breast cancer patients (70 patients with locally recurrent breast cancer and 65 patients with locally advanced breast cancer with unfavorable prognostic factors) who received the neutron therapy alone or in combination with the photon therapy. The neutron therapy was shown to be effective in multimodality treatment of patients with locally advanced and locally recurrent breast cancer. The 8-year survival rate in patients without repeated breast cancer recurrence was 87.6 ± 8.7% after the neutron and neutron-photon therapy and 54.3 ± 9.2% after the electron beam therapy.

  17. Overview of the projects recently developed by the advanced neutron environment team at the ILL

    Science.gov (United States)

    Bourgeat-Lami, Eric; Chapuis, Jean-François; Chastagnier, Jérémie; Demas, Steffen; Gonzales, Jean-Paul; Keay, Morley-Patrick; Laborier, Jean-Luc; Lelièvre-Berna, Eddy; Losserand, Olivier; Martin, Paul; Mélési, Louis; Petoukhov, Alexander; Pujol, Serge; Ragazzoni, Jean-Louis; Thomas, Frédéric; Tonon, Xavier

    2006-11-01

    Within the framework of the Millennium Programme, we have started the design and building of novel equipment with the aim at facilitating and diversifying the experimental conditions on Institut Laue-Langevin (ILL) and ILL-CRG instruments. We anticipate new devices for applying external parameters (pressure, temperature, magnetic or electric fields, etc.), handling the neutron beam polarisation (RF wide-band flipper, TOF-Cryopad, etc.) or carrying multi-task experiments. The facilities already in operation are briefly reviewed: 3 K cryogen-free cryostat hosting the Paris-Edinburgh pressure cell, 3 K pulse-tube top-loading cryostat with 700 K high-temperature insert, 2 K Joule-Thomson cryogen-free cryostat for Eulerian cradles, 20 mK dilution fridge for the recently acquired 15 T cryomagnet and a low-temperature gas-injection sample stick for Orange cryostats.

  18. Experimental Software Design of the Neutron Texture Diffractometer at China Advanced Research Reactor

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Neutron scattering lab is building our country's first neutron texture diffractometer, which will be used for the texture measurement and analysis in the materials science and engineering applications. The sample table and its measurement and control

  19. Global shielding analysis for the three-element core advanced neutron source reactor under normal operating conditions

    Energy Technology Data Exchange (ETDEWEB)

    Slater, C.O.; Bucholz, J.A.

    1995-08-01

    Two-dimensional discrete ordinates radiation transport calculations were performed for a model of the three-element core Advanced Neutron Source reactor design under normal operating conditions. The core consists of two concentric upper elements and a lower element radially centered in the annulus between the upper elements. The initial radiation transport calculations were performed with the DORT two-dimensional discrete ordinates radiation transport code using the 39-neutron-group/44-gamma-ray-group ANSL-V cross-section library, an S{sub 6} quadrature, and a P{sub 1} Legendre polynomial expansion of the cross sections to determine the fission neutron source distribution in the core fuel elements. These calculations were limited to neutron groups only. The final radiation transport calculations, also performed with DORT using the 39-neutron-group/44-gamma-ray-group ANSL-V cross-section library, an S{sub l0} quadrature, and a P{sub 3} Legendre polynomial expansion of the cross sections, produced neutron and gamma-ray fluxes over the full extent of the geometry model. Responses (or activities) at various locations in the model were then obtained by folding the appropriate response functions with the fluxes at those locations. Some comparisons were made with VENTURE-calculated (diffusion theory) 20-group neutron fluxes that were summed into four broad groups. Tne results were in reasonably good agreement when the effects of photoneutrons were not included, thus verifying the physics model upon which the shielding model was based. Photoneutrons increased the fast-neutron flux levels deep within the D{sub 2}0 several orders of magnitude. Results are presented as tables of activity values for selected radial and axial traverses, plots of the radial and axial traverse data, and activity contours superimposed on the calculational geometry model.

  20. High Neutron Fluence Survivability Testing of Advanced Fiber Bragg Grating Sensors

    International Nuclear Information System (INIS)

    The motivation for the reported research was to support NASA space nuclear power initiatives through the development of advanced fiber optic sensors for space-based nuclear power applications. The purpose of the high-neutron fluence testing was to demonstrate the survivability of fiber Bragg grating (FBG) sensors in a fission reactor environment. 520 FBGs were installed in the Ford reactor at the University of Michigan. The reactor was operated for 1012 effective full power hours resulting in a maximum neutron fluence of approximately 5x1019 n/cm2, and a maximum gamma dose of 2x103 MGy gamma. This work is significant in that, to the knowledge of the authors, the exposure levels obtained are approximately 1000 times higher than for any previously published experiment. Four different fiber compositions were evaluated. An 87% survival rate was observed for fiber Bragg gratings located at the fuel centerline. Optical Frequency Domain Reflectometry (OFDR), originally developed at the NASA Langley Research Center, can be used to interrogate several thousand low-reflectivity FBG strain and/or temperature sensors along a single optical fiber. A key advantage of the OFDR sensor technology for space nuclear power is the extremely low mass of the sensor, which consists of only a silica fiber 125μm in diameter. The sensors produced using this technology will fill applications in nuclear power for current reactor plants, emerging Generation-IV reactors, and for space nuclear power. The reported research was conducted by Luna Innovations and was funded through a Small Business Innovative Research (SBIR) contract with the NASA Glenn Research Center

  1. A Complex-Geometry Validation Experiment for Advanced Neutron Transport Codes

    Energy Technology Data Exchange (ETDEWEB)

    David W. Nigg; Anthony W. LaPorta; Joseph W. Nielsen; James Parry; Mark D. DeHart; Samuel E. Bays; William F. Skerjanc

    2013-11-01

    The Idaho National Laboratory (INL) has initiated a focused effort to upgrade legacy computational reactor physics software tools and protocols used for support of core fuel management and experiment management in the Advanced Test Reactor (ATR) and its companion critical facility (ATRC) at the INL.. This will be accomplished through the introduction of modern high-fidelity computational software and protocols, with appropriate new Verification and Validation (V&V) protocols, over the next 12-18 months. Stochastic and deterministic transport theory based reactor physics codes and nuclear data packages that support this effort include MCNP5[1], SCALE/KENO6[2], HELIOS[3], SCALE/NEWT[2], and ATTILA[4]. Furthermore, a capability for sensitivity analysis and uncertainty quantification based on the TSUNAMI[5] system has also been implemented. Finally, we are also evaluating the Serpent[6] and MC21[7] codes, as additional verification tools in the near term as well as for possible applications to full three-dimensional Monte Carlo based fuel management modeling in the longer term. On the experimental side, several new benchmark-quality code validation measurements based on neutron activation spectrometry have been conducted using the ATRC. Results for the first four experiments, focused on neutron spectrum measurements within the Northwest Large In-Pile Tube (NW LIPT) and in the core fuel elements surrounding the NW LIPT and the diametrically opposite Southeast IPT have been reported [8,9]. A fifth, very recent, experiment focused on detailed measurements of the element-to-element core power distribution is summarized here and examples of the use of the measured data for validation of corresponding MCNP5, HELIOS, NEWT, and Serpent computational models using modern least-square adjustment methods are provided.

  2. Neutron radiation therapy: application of advanced technology to the treatment of cancer

    CERN Document Server

    Maughan, R L; Kota, C; Burmeister, J; Porter, A T; Forman, J D; Blosser, H G; Blosser, E; Blosser, G

    1999-01-01

    The design and construction of a unique superconducting cyclotron for use in fast neutron radiation therapy is described. The clinical results obtained in the treatment of adenocarcinoma of the prostate with this accelerator are presented. Future use of the boron neutron capture reaction as a means of enhancing fast neutron therapy in the treatment of patients with brain tumors (glioblastoma multiforme) is also discussed.

  3. A neutron poison tritium breeding controller applied to a water cooled fusion reactor model

    International Nuclear Information System (INIS)

    Highlights: • The issue of a potentially producing a large tritium surplus inventory, within a solid breeder, is addressed. • A possible solution to this problem is presented in the form of a neutron poison based tritium production controller. • The tritium surplus inventory has been modelled by the FATI code for a simplified WCCB model and as a function of time. • It has been demonstrated that the tritium surplus inventory can be managed, which may impact on safety considerations. - Abstract: The generation of tritium in sufficient quantities is an absolute requirement for a next step fusion device such as DEMO due to the scarcity of tritium sources. Although the production of sufficient quantities of tritium will be one of the main challenges for DEMO, within an energy economy featuring several fusion power plants the active control of tritium production may be required in order to manage surplus tritium inventories at power plant sites. The primary reason for controlling the tritium inventory in such an economy would therefore be to minimise the risk and storage costs associated with large quantities of surplus tritium. In order to ensure that enough tritium will be produced in a reactor which contains a solid tritium breeder, over the reactor's lifetime, the tritium breeding rate at the beginning of its lifetime is relatively high and reduces over time. This causes a large surplus tritium inventory to build up until approximately halfway through the lifetime of the blanket, when the inventory begins to decrease. This surplus tritium inventory could exceed several tens of kilograms of tritium, impacting on possible safety and licensing conditions that may exist. This paper describes a possible solution to the surplus tritium inventory problem that involves neutron poison injection into the coolant, which is managed with a tritium breeding controller. A simple PID controller and is used to manage the injection of the neutron absorbing compounds into

  4. Diagnosing Implosion Performance at the National Ignition Facility by Means of Advanced Neutron-Spectrometry and Neutron-Imaging Techniques

    International Nuclear Information System (INIS)

    Full text: Proper assembly of capsule mass, as manifested through the evolution of fuel areal density, is essential for achieving hot-spot ignition planned at the National Ignition Facility (NIF). Experimental information about areal density and areal-density asymmetries, hot-spot ion temperature (Ti) and yield (Yn) are therefore critical for understanding the assembly of the fuel. To obtain this information, a suite of neutron Time-of-Flight (nTOF) spectrometers and a Magnetic Recoil Spectrometer (MRS) has been commissioned and extensively used on the NIF for measurements of the neutron spectrum in the energy range from 1.5 to 20 MeV. This range covers all essential details of the neutron spectrum, allowing for the determination of areal density, Yn, and Ti. The spectrometers are fielded at different locations around the implosion for directional measurements of the neutron spectrum, also allowing for determination of areal-density asymmetries and possible kinetic effects. The data obtained from these diagnostics have been essential to the progress of the National Ignition Campaign (NIC), indicating that the implosion performance, characterized by the Experimental Ignition Threshold Factor (ITFx), has improved about two orders of magnitude since the first cryogenic shot taken in September 2010. Areal-density values greater than 1 g/cm2 are now readily achieved. By combining the areal-density data with information about the spatial extent of the high-density region obtained from Neutron Imaging System (NIS), it has been demonstrated that densities above 500 g/cc and pressure-time (Pτ) products in excess of 10 atm s have been achieved, which are according to HYDRA simulations about a factor of three from ignition conditions. (author)

  5. Determination of uranium and thorium by neutron activation analysis applied to fossil samples dating

    Energy Technology Data Exchange (ETDEWEB)

    Ticianelli, Regina B.; Figueiredo, Ana Maria Graciano; Zahn, Guilherme S. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Kinoshita, Angela; Baffa, Oswaldo [Universidade de Sao Paulo (FFCRLP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto. Dept. de Fisica

    2011-07-01

    Electron Spin Resonance (ESR) dating is based on the fact that ionizing radiation can create stable free radicals in insulating materials, like tooth enamel and bones. The concentration of these radicals - determined by ESR - is a function of the dose deposed in the sample along the years. The accumulated dose of radiation, called Archaeological Dose, is produced by the exposition to environmental radiation provided by U, Th, K and cosmic rays. If the environmental dose rate in the site where the fossil sample is found is known, it is possible to convert this dose into the age of the sample. The annual dose rate coming from the radioactive elements present in the soil and in the sample itself can be calculated by determining the U, Th and K concentration. Therefore, the determination of the dose rate depends on the concentration of these main radioactive elements. Neutron Activation Analysis has the sensitivity and the accuracy necessary to determine U, Th and K with this objective. Depending on the composition of the sample, the determination of U and Th can be improved irradiating the sample inside a Cd capsule, reducing the thermal neutron incidence on the sample and, therefore, diminishing the activation of possible interfering nuclides. In this study the optimal irradiation and counting conditions were established for U and Th determination in fossil teeth and soil. (author)

  6. Analysis of Petroleum Technology Advances Through Applied Research by Independent Oil Producers

    Energy Technology Data Exchange (ETDEWEB)

    Brashear, Jerry P.; North, Walter B.; Thomas Charles P.; Becker, Alan B.; Faulder, David D.

    2000-01-12

    Petroleum Technology Advances Through Applied Research by Independent Oil Producers is a program of the National Oil Research Program, U.S. Department of Energy. Between 1995 and 1998, the program competitively selected and cost-shared twenty-two projects with small producers. The purpose was to involve small independent producers in testing technologies of interest to them that would advance (directly or indirectly) one or more of four national program objectives: (1) Extend the productive life of reservoirs; (2) Increase production and/or reserves; (3) Improve environmental performance; and (4) Broaden the exchange of technology information.

  7. Instrumental neutron activation analysis applied to the chemical composition of steel

    International Nuclear Information System (INIS)

    In the technological application of steel, the knowledge of its chemical composition is of fundamental importance as it is directly related to various properties, such as, mechanical properties, corrosion resistance, temperability and others. Instrumental Neutron Activation Analysis, INAA, is an appropriate technique in the evaluation of the chemical composition of steel and other metallurgical materials due to the possibility of simultaneous determination of a great number of elements without the inconvenience of sample dissolution. Element determination is achieved with good accuracy and precision for major and minor constituents as well as for trace elements. In this paper, INAA was used in the determination of As, Co, Cu, Mn, Mo, V and W in steel and iron samples and in certified reference materials. The obtained accuracy and precision were less than 10% for most of the elements confirming the possibility of its use in the study of metallic samples and in the certification of new reference materials. (author)

  8. Advanced Monte Carlo procedure for the IFMIF d-Li neutron source term based on evaluated cross section data

    CERN Document Server

    Simakov, S P; Moellendorff, U V; Schmuck, I; Konobeev, A Y; Korovin, Y A; Pereslavtsev, P

    2002-01-01

    A newly developed computational procedure is presented for the generation of d-Li source neutrons in Monte Carlo transport calculations based on the use of evaluated double-differential d+ sup 6 sup , sup 7 Li cross section data. A new code M sup c DeLicious was developed as an extension to MCNP4C to enable neutronics design calculations for the d-Li based IFMIF neutron source making use of the evaluated deuteron data files. The M sup c DeLicious code was checked against available experimental data and calculation results of M sup c DeLi and MCNPX, both of which use built-in analytical models for the Li(d, xn) reaction. It is shown that M sup c DeLicious along with newly evaluated d+ sup 6 sup , sup 7 Li data is superior in predicting the characteristics of the d-Li neutron source. As this approach makes use of tabulated Li(d, xn) cross sections, the accuracy of the IFMIF d-Li neutron source term can be steadily improved with more advanced and validated data.

  9. Preparation of a one-curie 171Tm target for the Detector for Advanced Neutron Capture Experiments (DANCE)

    Energy Technology Data Exchange (ETDEWEB)

    Schwantes, Jon M.; Taylor, Wayne A.; Rundberg, Robert S.; Vieira, David J.

    2008-05-15

    Roughly one curie of 171Tm (t1/2=1.92a) has been produced and purified for the purpose of making a nuclear target for the first measurements of its neutron capture cross section. Target preparation consisted of three key steps: (1) material production; (2) separation and purification; and (3) electrodeposition onto a suitable backing material. Approximately 1.5 mg of the target material (at the time of separation) was produced by irradiating roughly 250 mg of its stable enriched 170Er lanthanide neighbor with neutrons at the ILL reactor in France. This production method resulted in a “difficult-to-separate” 1:167 mixture of near-neighboring lanthanides, Tm and Er. Separation and purification was accomplished using high-performance liquid chromatorgraphy (HPLC), with a proprietary cation exchange column (Dionex, CS-3) and alpha-hydroxyisobutyric acid (a-HIB) eluent. This technique yielded a final product of ~95% purity with respect to Tm. A portion (20 ug) of the Tm was electrodeposited on thin Be foil and delivered to the Los Alamos Neutron Science CEnter (LANSCE) for preliminary analysis of its neutron capture cross section using the Detector for Advanced Neutron Capture Experiments (DANCE). This paper discusses the major hurdles associated with the separation and purification step including, scale-up issues related to the use of HPLC for material separation and purification of the target material from a-HIB and 4-(2-pyridylazo)resorcinol (PAR) colorant.

  10. Preparation of a one-curie 171Tm target for the detector for advanced neutron capture experiments (DANCE)

    International Nuclear Information System (INIS)

    Approximately one curie of 171Tm (T1/2 = 1.92a) has been produced and purified for the purpose of making a nuclear target for the first measurements of its neutron capture cross section. Target preparation consisted of three key steps: (1) material production; (2) separation and purification; and (3) electrodeposition onto a suitable backing material. Approximately 1.5 mg of the target material (at the time of separation) was produced by irradiating ca. 250 mg of its stable enriched 170Er lanthanide neighbour with neutrons at the ILL reactor in France. This production method resulted in a 'difficult-to-separate' 1:167 mixture of near-neighboring lanthanides, Tm and Er. Separation and purification was accomplished using high-performance liquid chromatography (HPLC), with a proprietary cation-exchange column (Dionex, CS-3) and alphahydroxyisobutyric acid (α-HIB) eluent. This technique yielded a final product of ∼95% purity with respect to Tm. A portion (20 μg) of the Tm was electrodeposited onto thin Be foil and delivered to the Los Alamos Neutron Science Center (LANSCE) for preliminary analysis of its neutron capture cross section using the Detector for Advanced Neutron Capture Experiments (DANCE). This paper discusses the major hurdles associated with the separation and purification step, including scale-up issues related to the use of HPLC for material separation and purification of the target material from α-HIB and 4-(2-pyridylazo)resorcinol (PAR) colorant. (author)

  11. Applied solid state science advances in materials and device research 3

    CERN Document Server

    Wolfe, Raymond

    2013-01-01

    Applied Solid State Science: Advances in Materials and Device Research, Volume 3 covers reviews that are directly related to the two devices which are the epitome of applied solid state science - the transistor and the laser. The book discusses the physics of multilayer-gate IGFET memories; the application of the transient charge technique in drift velocity; and trapping in semiconductors and in materials used in xerography, nuclear particle detectors, and space-charge-limited devices; as well as thin film transistors. The text describes the manipulation of laser beams in solids and discusses

  12. Boron neutron capture therapy for advanced salivary gland carcinoma in head and neck

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a among the radiation treatments known to have a selective lethal effect on tumor cells. This study summarizes the tumor responses and the acute and late adverse effects of BNCT in the treatment of patients with both recurrent and newly diagnosed T4 salivary gland carcinoma. Two patients with recurrent cancer and 3 with newly diagnosed T4 advanced malignancy were registered between October 2003 and September 2007, with the approval of the medical ethics committees of Kawasaki Medical School and Kyoto University. BNCT was performed, in a single fraction using an epithermal beam, at Japan Research Reactor 4. All patients achieved a complete response within 6 months of treatment. The median duration of the complete response was 24.0 months; the median overall survival time was 32.0 months. Three of the 5 patients are still alive; the other 2 died of distant metastatic disease. Open biopsy of the parotid gland after BNCT was performed in 1 patient and revealed no residual viable cancer cells and no serious damage to the normal glandular system. Although mild alopecia, xerostomia, and fatigue occurred in all patients, there were no severe adverse effects of grade 3 or greater. Our preliminary results demonstrate that BNCT is a potential curative therapy for patients with salivary gland carcinoma. The treatment does not cause any serious adverse effects, and may be used regardless of whether the primary tumor has been previously treated. (author)

  13. Oxidation behavior of plasma sintered beryllium-titanium intermetallic compounds as an advanced neutron multiplier

    Science.gov (United States)

    Kim, Jae-Hwan; Nakamichi, Masaru

    2013-07-01

    Beryllium intermetallic compounds (beryllides) such as Be12Ti are very promising candidates for advanced neutron multiplier materials in a demonstration fusion power reactor (DEMO). However, beryllides are too brittle to be fabricated either into pebble-type or rod-type shapes via conventional methods (i.e. arc melting and hot isostatic pressing). We have proposed a plasma sintering technique as a new method for beryllide fabrication, and our studies on the properties of plasma sintered beryllides are ongoing. In the present work, the oxidation properties of plasma sintered beryllides were investigated at 1273 K for 24 h in a dry air atmosphere to evaluate the high temperature properties of this material. Thermal gravimetry measurements indicate that specimens with larger fractions of Be12Ti phase corresponding to samples that have been sintered for longer time periods, exhibit superior oxidation properties. Our evaluation of the oxidation behavior of each phase in our beryllide samples is as follows: Be12Ti and Be17Ti2 both have good oxidation resistance, owing to the formation of dense and protective scales, while the Be and Be2Ti phases are mainly responsible for thermal-gravimetry (TG) weight gains, which is indicative of severe oxidation. We attribute the degradation in oxidation resistance specifically to Be2Ti that transforms into TiO2, and also find this phase to be the cause of deterioration in the mechanical properties of samples, owing to cracks near Be2Ti phase conglomerates.

  14. Preliminary fracture analysis of the core pressure boundary tube for the Advanced Neutron Source Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, K.C. [Univ. of Turabo, Gurabo, Puerto (Puerto Rico). College of Engineering; Yahr, G.T. [Oak Ridge National Lab., TN (United States)

    1995-08-01

    The outer core pressure boundary tube (CPBT) of the Advanced neutron Source (ANS) reactor being designed at Oak Ridge National Laboratory is currently specified as being composed of 6061-T6 aluminum. ASME Boiler and Pressure Vessel Code fracture analysis rules for nuclear components are based on the use of ferritic steels; the expressions, tables, charts and equations were all developed from tests and analyses conducted for ferritic steels. Because of the nature of the Code, design with thin aluminum requires analytical approaches that do not directly follow the Code. The intent of this report is to present a methodology comparable to the ASME Code for ensuring the prevention of nonductile fracture of the CPBT in the ANS reactor. 6061-T6 aluminum is known to be a relatively brittle material; the linear elastic fracture mechanics (LEFM) approach is utilized to determine allowable flaw sizes for the CPBT. A J-analysis following the procedure developed by the Electric Power Research Institute was conducted as a check; the results matched those for the LEFM analysis for the cases analyzed. Since 6061-T6 is known to embrittle when irradiated, the reduction in K{sub Q} due to irradiation is considered in the analysis. In anticipation of probable requirements regarding maximum allowable flaw size, a survey of nondestructive inspection capabilities is also presented. A discussion of probabilistic fracture mechanics approaches, principally Monte Carlo techniques, is included in this report as an introduction to what quantifying the probability of nonductile failure of the CPBT may entail.

  15. Modeling heat generation and flow in the Advanced Neutron Source Corrosion Test Loop specimen

    International Nuclear Information System (INIS)

    A finite difference computer code HEATING5 was used to model heat generation and flow in a typical experiment envisioned for the Advanced Neutron Source Corrosion Test Loop. The electrical resistivity and thermal conductivity of the test specimen were allowed to vary with local temperature, and the corrosion layer thickness was assigned along the length of the specimen in the manner predicted by the Griess Correlation. The computer solved the two-dimensional transport problem for a given total power dissipated in the specimen and stipulated coolant temperatures and water-side heat-transfer coefficients. The computed specimen temperatures were compared with those calculated on the basis of approximate analytical equations involving the total power dissipation and the assignment of the physical properties based on temperatures at single axial points on the specimen. The comparisons indicate that when temperature variations are large along the axis of the specimen, the variation in local heat flux should not be overlooked when using approximate equations or models. The approximate equations are most accurate near the center of the specimen where the heat flux remains closest to the average value, and in that region the calculated quantities agree closely with the results of the computer code. 4 figs., 1 tab

  16. Report of the Advanced Neutron Source (ANS) safety workshop, Knoxville, Tennessee, October 25--26, 1988

    International Nuclear Information System (INIS)

    On October 25--26, 1988, about 60 people took part in an Advanced Neutron Source (ANS) Safety Workshop, organized in cooperation with the Oak Ridge Operations (ORO) Office of the Department of Energy (DOE) and held in Knoxville, Tennessee. After a plenary session at which ANS Project staff presented status reports on the ANS design, research and development (R and D), and safety analysis efforts, the workshop broke into three working groups, each covering a different topic: Environmental and Waste Management, Applicable Regulatory Safety Criteria and Goals, and Reactor Concepts. Each group was asked to review the Project's approach to safety-related issues and to provide guidance on future reactor safety needs or directions for the Project. With the help of able chairmen, assisted by reporters and secretarial support, the working groups were extremely successful. Draft reports from each group were prepared before the workshop closed, and the major findings of each group were presented for review and discussion by the entire workshop attendance. This report contains the final version of the group reports, incorporating the results of the overall review by all the workshop participants

  17. Detecting gravitational waves from mountains on neutron stars in the Advanced Detector Era

    CERN Document Server

    Haskell, Brynmor; Patruno, Alessandro; Oppenoorth, Manuel; Melatos, Andrew; Lasky, Paul

    2015-01-01

    Rapidly rotating Neutron Stars (NSs) in Low Mass X-ray Binaries (LMXBs) are thought to be interesting sources of Gravitational Waves (GWs) for current and next generation ground based detectors, such as Advanced LIGO and the Einstein Telescope. The main reason is that many of the NS in these systems appear to be spinning well below their Keplerian breakup frequency, and it has been suggested that torques associated with GW emission may be setting the observed spin period. This assumption has been used extensively in the literature to assess the strength of the likely gravitational wave signal. There is now, however, a significant amount of theoretical and observation work that suggests that this may not be the case, and that GW emission is unlikely to be setting the spin equilibrium period in many systems. In this paper we take a different starting point and predict the GW signal strength for two physical mechanisms that are likely to be at work in LMXBs: crustal mountains due to thermal asymmetries and magne...

  18. Editorial: Advances in Health Education Applying E-Learning, Simulations and Distance Technologies

    Directory of Open Access Journals (Sweden)

    Andre W. Kushniruk

    2011-03-01

    Full Text Available This special issue of the KM&EL international journal is dedicated to coverage of novel advances in health professional education applying e-Learning, simulations and distance education technologies. Modern healthcare is beginning to be transformed through the emergence of new information technologies and rapid advances in health informatics. Advances such as electronic health record systems (EHRs, clinical decision support systems and other advanced information systems such as public health surveillance systems are rapidly being deployed worldwide. The education of health professionals such as medical, nursing and allied health professionals will require an improved understanding of these technologies and how they will transform their healthcare practice. However, currently there is a lack of integration of knowledge and skills related to such technology in health professional education. In this issue of the journal we present articles that describe a set of novel approaches to integrating essential health information technology into the education of health professionals, as well as the use of advanced information technologies and e-Learning approaches for improving health professional education. The approaches range from use of simulations to development of novel Web-based platforms for allowing students to interact with the technologies and healthcare practices that are rapidly changing healthcare.

  19. The ion beam sputtering facility at KURRI: Coatings for advanced neutron optical devices

    Science.gov (United States)

    Hino, Masahiro; Oda, Tatsuro; Kitaguchi, Masaaki; Yamada, Norifumi L.; Tasaki, Seiji; Kawabata, Yuji

    2015-10-01

    We describe a film coating facility for the development of multilayer mirrors for use in neutron optical devices that handle slow neutron beams. Recently, we succeeded in fabricating a large neutron supermirror with high reflectivity using an ion beam sputtering system (KUR-IBS), as well as all neutron supermirrors in two neutron guide tubes at BL06 at J-PARC/MLF. We also realized a large flexible self-standing m=5 NiC/Ti supermirror and very small d-spacing (d=1.65 nm) multilayer sheets. In this paper, we present an overview of the performance and utility of non-magnetic neutron multilayer mirrors fabricated with the KUR-IBS

  20. The ion beam sputtering facility at KURRI: Coatings for advanced neutron optical devices

    Energy Technology Data Exchange (ETDEWEB)

    Hino, Masahiro, E-mail: hino@rri.kyoto-u.ac.jp [Research Reactor Institute, Kyoto university, Kumatori, Osaka 590-0494 (Japan); Oda, Tatsuro [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8540 (Japan); Kitaguchi, Masaaki [Center for Experimental Studies, KMI, Nagoya University, Nagoya 464-8602 (Japan); Yamada, Norifumi L. [Neutron Science Laboratory, High Energy Accelerator Research Organization, 203-1 Shirakata, Tokai, Ibaraki 319-1106 (Japan); Tasaki, Seiji [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8540 (Japan); Kawabata, Yuji [Research Reactor Institute, Kyoto university, Kumatori, Osaka 590-0494 (Japan)

    2015-10-11

    We describe a film coating facility for the development of multilayer mirrors for use in neutron optical devices that handle slow neutron beams. Recently, we succeeded in fabricating a large neutron supermirror with high reflectivity using an ion beam sputtering system (KUR-IBS), as well as all neutron supermirrors in two neutron guide tubes at BL06 at J-PARC/MLF. We also realized a large flexible self-standing m=5 NiC/Ti supermirror and very small d-spacing (d=1.65 nm) multilayer sheets. In this paper, we present an overview of the performance and utility of non-magnetic neutron multilayer mirrors fabricated with the KUR-IBS.

  1. Neutron activation analysis applied to the chemical composition of metallic materials

    International Nuclear Information System (INIS)

    The physical properties of metallic materials, such as mechanical properties, corrosion resistance and others are determined by their chemical composition, which influences the various steps of the production process and the economic value attained by the materials. Instrumental neutron activation analysis was used in this work to evaluate the chemical composition of iron, steel, silicon and ferrosilicon reference materials. The concentration of the elements As, Co, Cr, Mn, Mo, Ni, V and W were analyzed in the iron and steel samples whereas As, Br, Co, Cr, K, Eu, Fe, La, Mn, Mo, Na, Nd, U, Th, Sb, Sc, Sm, Tb, V, W and Yb were determined in silicon and ferrosilicon samples. Accuracy was assessed comparing obtained results to reference materials certified values. Results of about 10 % were achieved for most of the elements. Precision was assessed by replicate measurements, and the results of about 10 % were also achieved. Accuracy and precision results showed that the technique is suitable for the metallic materials composition analysis. Interferences of Cr and Mn in V, Fe and Co in Mn; Co in Fe and Cr in Ti were quantified and only the last one was critical to the analysis of the materials employed in this work. (author)

  2. Weapons Neutron Research Facility (WNR)

    Data.gov (United States)

    Federal Laboratory Consortium — The Weapons Neutron Research Facility (WNR) provides neutron and proton beams for basic, applied, and defense-related research. Neutron beams with energies ranging...

  3. On an optimized neutron shielding for an advanced molten salt fast reactor design

    International Nuclear Information System (INIS)

    The molten salt reactor technology has gained renewed interest. In contrast to the historic molten salt reactors, the current projects are based on designing a molten salt fast reactor. Thus the shielding becomes significantly more challenging than in historic concepts. One very interesting and innovative result of the most recent EURATOM project on molten salt reactors – EVOL – is the fluid flow optimized design of the inner core vessel using curved blanket walls. The developed structure leads to a very uniform flow distribution. The design avoids all core internal structures. On the basis of this new geometry a model for neutron physics calculation is presented and applied for a shielding optimization. Based on these results an optimized shielding strategy is developed for the molten salt fast reactor to keep the fluence in the safety related outer vessel below expected limit values. A lifetime of 80 years can be assured, but the size of the core/blanket system has to be significantly increased and will finally be comparable to a sodium cooled fast reactor. The HELIOS results are verified against Monte-Carlo calculations with very satisfactory agreement for a deep penetration problem. (author)

  4. Proceedings of the 1986 workshop on advanced time-of-flight neutron powder diffraction

    International Nuclear Information System (INIS)

    This report contains abstracts of talks and summaries of discussions from a small workshop held to discuss the future of time-of-flight neutron powder diffraction and its implementation at the Los Alamos Neutron Scattering Center. 47 refs., 3 figs

  5. Design of Stopper of Prompt Gamma Neutron Activation Analysis Facility at China Advanced Research Reactor

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The PGNAA facility consists of the filtered collimated neutron beam, the shielding of the whole facility, the control system, the detecting equipment and the data acquisition and analysis system. The neutron beam is filtered by a mono-crystalline bismuth filter,

  6. Advanced broad-band solid-state supermirror polarizers for cold neutrons

    CERN Document Server

    Petukhov, A K; Bigault, T; Courtois, P; Jullien, D; Soldner, T

    2016-01-01

    An ideal solid-state supermirror (SM) neutron polarizer assumes total reflection of neutrons from the SM coating for one spin-component and total absorption for the other, thus providing a perfectly polarized neutron beam at the exit. However, in practice, the substrate's neutron-nucleai optical potential does not match perfectly that for spin-down neutrons in the SM. For a positive step in the optical potential (as in a Fe/SiN(x) SM on Si substrate), this mismatch results in spin-independent total reflection for neutrons with small momentum transfer Q, limiting the useful neutron bandwidth in the low-Q region. To overcome this limitation, we propose to replace Si single-crystal substrates by media with higher optical potential than that for spin-down neutrons in the SM ferromagnetic layers. We found single-crystal sapphire and single-crystal quartz as good candidates for solid-state Fe/SiN(x) SM polarizers. To verify this idea, we coated a thick plate of single-crystal sapphire with a m=2.4 Fe/SiN(x) SM. At ...

  7. Dipolar structures in magnetite ferrofluids studied with small-angle neutron scattering with and without applied magnetic field.

    Science.gov (United States)

    Klokkenburg, M; Erné, B H; Wiedenmann, A; Petukhov, A V; Philipse, A P

    2007-05-01

    Field-induced structure formation in a ferrofluid with well-defined magnetite nanoparticles with a permanent magnetic dipole moment was studied with small-angle neutron scattering (SANS) as a function of the magnetic interactions. The interactions were tuned by adjusting the size of the well-defined, single-magnetic-domain magnetite (Fe3O4) particles and by applying an external magnetic field. For decreasing particle dipole moments, the data show a progressive distortion of the hexagonal symmetry, resulting from the formation of magnetic sheets. The SANS data show qualitative agreement with recent cryogenic transmission electron microscopy results obtained in 2D [Klokkenburg, Phys. Rev. Lett. 97, 185702 (2006)] on the same ferrofluids. PMID:17677066

  8. Applied research and development of neutron activation analysis - The study on human health and environment by neutron activation analysis of biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seung Yeon; Yoo, Jong Ik; Lee, Jae Kwang; Lee, Sung Jun; Lee, Sang Sun; Jeon, Ki Hong; Na, Kyung Won; Kang, Sang Hun [Yonsei University, Seoul (Korea)

    2000-04-01

    With the development of the precise quantitative analytical method for the analysis of trace elements in the various biological samples such as hair and food, evaluation in view of health and environment to the trace elements in various sources which can be introduced inside human body was done. The trace elemental distribution in Korean total diet and representative food stuff was identified first. With the project the elemental distributions in supplemental healthy food and Korean and Chinese origin oriental medicine were identified. The amount of trace elements ingested with the hair analysis of oriental medicine takers were also estimated. The amounts of trace elements inhaled with the analysis of foundry air, blood and hair of foundry workers were also estimated. The basic estimation method in view of health and environment with the neutron activation analysis of biological samples such as foods and hair was established with the result. Nationwide usage system of the NAA facility in Hanaro in many different and important areas of biological area can be initiated with the results. The output of the project can support public heath, environment, and medical research area. The results can be applied for the process of micronutrients enhanced health food production and for the health safety and health status enhancement with the additional necessary data expansion and the development of various evaluation technique. 19 refs., 7 figs., 23 tabs. (Author)

  9. Neutron cross-sections for advanced nuclear systems: the n_TOF project at CERN

    Science.gov (United States)

    Barbagallo, M.; Mastromarco, M.; Colonna, N.; Altstadt, S.; Andrzejewski, J.; Audouin, L.; Bécares, V.; Bečvář, F.; Belloni, F.; Berthoumieux, E.; Billowes, J.; Bosnar, D.; Brugger, M.; Calviani, M.; Calviño, F.; Cano-Ott, D.; Carrapiço, C.; Cerutti, F.; Chiaveri, E.; Chin, M.; Cortés, G.; Cortés-Giraldo, M. A.; Diakaki, M.; Domingo-Pardo, C.; Duran, I.; Dressler, R.; Eleftheriadis, C.; Ferrari, A.; Fraval, K.; Ganesan, S.; García, A. R.; Giubrone, G.; Gonçalves, I. F.; González-Romero, E.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Hernández-Prieto, A.; Jenkins, D. G.; Jericha, E.; Kadi, Y.; Käppeler, F.; Karadimos, D.; Kivel, N.; Koehler, P.; Krtička, M.; Kroll, J.; Lampoudis, C.; Langer, C.; Leal-Cidoncha, E.; Lederer, C.; Leeb, H.; Leong, L. S.; Losito, R.; Manousos, A.; Marganiec, J.; Martínez, T.; Massimi, C.; Mastinu, P. F.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, F.; Mirea, M.; Mondalaers, W.; Paradela, C.; Pavlik, A.; Perkowski, J.; Plompen, A.; Praena, J.; Quesada, J. M.; Rauscher, T.; Reifarth, R.; Riego, A.; Rubbia, C.; Sabaté-Gilarte, M.; Sarmento, R.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Tagliente, G.; Tain, J. L.; Tarrío, D.; Tassan-Got, L.; Tsinganis, A.; Valenta, S.; Vannini, G.; Variale, V.; Vaz, P.; Ventura, A.; Vermeulen, M. J.; Vlachoudis, V.; Vlastou, R.; Wallner, A.; Ware, T.; Weigand, M.; Weiß, C.; Wright, T.; Žugec, P.

    2014-12-01

    The study of neutron-induced reactions is of high relevance in a wide variety of fields, ranging from stellar nucleosynthesis and fundamental nuclear physics to applications of nuclear technology. In nuclear energy, high accuracy neutron data are needed for the development of Generation IV fast reactors and accelerator driven systems, these last aimed specifically at nuclear waste incineration, as well as for research on innovative fuel cycles. In this context, a high luminosity Neutron Time Of Flight facility, n_TOF, is operating at CERN since more than a decade, with the aim of providing new, high accuracy and high resolution neutron cross-sections. Thanks to the features of the neutron beam, a rich experimental program relevant to nuclear technology has been carried out so far. The program will be further expanded in the near future, thanks in particular to a new high-flux experimental area, now under construction.

  10. Experimental tests of an advanced proton-to-neutron converter at ISOLDE-CERN

    CERN Document Server

    Gottberg, A; Luis, R; Ramos, J P; Seiffert, C; Cimmino, S; Marzari, S; Crepieux, B; Manea, V; Wolf, R N; Wienholtz, F; Kreim, S; Fedosseev, V N; Marsh, B A; Rothe, S; Vaz, P; Marques, J G; Stora, T

    2014-01-01

    The suppression of isobaric contaminations is of growing importance for many scientific programs using radioactive isotopes produced at isotope separation on-line (ISOL) facilities, such as ISOLDE-CERN. A solid tungsten proton-to-neutron converter has been used for ten years to produce neutron-rich fission fragments from an UC x target while suppressing the production of neutron-deficient isobaric contaminants. The remaining contamination is mainly produced by primary protons that are scattered by the heavy neutron converter and finally impinge on the UC x target itself. Therefore, the knowledge of the energy-dependant cross-sections of proton and neutron induced fission events is crucial in order to evaluate future converter concepts.

  11. Neutron cross-sections for advanced nuclear systems: the n_TOF project at CERN

    Directory of Open Access Journals (Sweden)

    Barbagallo M.

    2014-01-01

    Full Text Available The study of neutron-induced reactions is of high relevance in a wide variety of fields, ranging from stellar nucleosynthesis and fundamental nuclear physics to applications of nuclear technology. In nuclear energy, high accuracy neutron data are needed for the development of Generation IV fast reactors and accelerator driven systems, these last aimed specifically at nuclear waste incineration, as well as for research on innovative fuel cycles. In this context, a high luminosity Neutron Time Of Flight facility, n_TOF, is operating at CERN since more than a decade, with the aim of providing new, high accuracy and high resolution neutron cross-sections. Thanks to the features of the neutron beam, a rich experimental program relevant to nuclear technology has been carried out so far. The program will be further expanded in the near future, thanks in particular to a new high-flux experimental area, now under construction.

  12. An Information-Theoretical Approach to Image Resolution Applied to Neutron Imaging Detectors based upon Individual Discriminator Signals

    OpenAIRE

    Clergeau, Jean-François; Ferraton, Matthieu; Guérard, Bruno; Khaplanov, Anton; Piscitelli, Francesco; Platz, Martin; Rigal, Jean-Marie; Van Esch, Patrick; Daullé, Thibault

    2013-01-01

    1D or 2D neutron imaging detectors with individual wire or strip readout using discriminators have the advantage of being able to treat several neutron impacts partially overlapping in time, hence reducing global dead time. A single neutron impact usually gives rise to several discriminator signals. In this paper, we introduce an information-theoretical definition of image resolution. Two point-like spots of neutron impacts with a given distance between them act as a source of information (ea...

  13. RELAP5 analyses of two hypothetical flow reversal events for the advanced neutron source reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chen, N.C.J.; Wendel, M.W.; Yoder, G.L. Jr. [Oak Ridge National Lab., TN (United States)

    1995-09-01

    This paper presents RELAP5 results of two hypothetical, low flow transients analyzed as part of the Advanced Neutron Source Reactor safety program. The reactor design features four independent coolant loops (three active and one in standby), each containing a main curculation pump (with battery powered pony motor), heat exchanger, an accumulator, and a check valve. The first transient assumes one of these pumps fails, and additionally, that the check valve in that loop remains stuck in the open position. This accident is considered extremely unlikely. Flow reverses in this loop, reducing the core flow because much of the coolant is diverted from the intact loops back through the failed loop. The second transient examines a 102-mm-diam instantaneous pipe break near the core inlet (the worst break location). A break is assumed to occur 90 s after a total loss-of-offsite power. Core flow reversal occurs because accumulator injection overpowers the diminishing pump flow. Safety margins are evaluated against four thermal limits: T{sub wall}=T{sub sat}, incipient boiling, onset of significant void, and critical heat flux. For the first transient, the results show that these limits are not exceeded (at a 95% non-exceedance probability level) if the pony motor battery lasts 30 minutes (the present design value). For the second transient, the results show that the closest approach of the fuel surface temperature to the local saturation temperature during core flow reversal is about 39{degrees}C. Therefore the fuel remains cool during this transient. Although this work is done specifically for the ANSR geometry and operating conditions, the general conclusions may be applicable to other highly subcooled reactor systems.

  14. Update to advanced neutron source steady-state thermal-hydraulic report

    Energy Technology Data Exchange (ETDEWEB)

    Yoder, G.L.; Carbajo, J.J.; Morris, D.G.; Nelson, W.R.

    1996-05-01

    This report is intended to be a supplement to ORNL/TM-12398, Steady-State Thermal-Hydraulic Design Analysis of the Advanced Neutron Source Reactor. It updates the core thermal-hydrualic design to the latest three-element configuration and also provides the most recent information on the thermal-hydraulic statistical uncertainty analysis. In addition, it includes calculations of beam tube cooling and control rod lift forces, which were not addressed in the initial report. This report describes work that is a snapshot in time as it stood at the end of the project. The three-element core calculations include a description of changes made to the overall coolant system; however, most of the analysis is focused on fuel loading thermal-hydraulic calculations. This analysis uses updated uncertainty values and indicates that a two-dimensional fuel grading in the three-element core would still be necessary to meet the desired operating and safety criteria. Analysis of cooling in the reflector tank examines various cooling options for the reflector tank components. This work investigated multiple forced convection designs as well as natural convection cooling requirements. Lift forces on the inner control rods caused by the upward coolant flow were also examined. Initial control rod designs were such that a sheared control rod would tend to lift because of flow forces. Design changes were recommended that would eliminate this issue. They included geometry changes to the inner control rod cooling channels, changes to the orificing in the central hole region, and reduction of inner control rod coolant velocity.

  15. Proceedings of the 182nd basic science seminar (The workshop on neutron structural biology ) 'New frontiers of structural biology advanced by solution scattering'

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, Satoru (ed.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-03-01

    182nd advanced science seminar (the workshop on neutron structural biology) was held in February 9-10, 2000 at Tokai. Thirty-six participants from universities, research institutes, and private companies took part in the workshop, and total of 24 lectures were given. This proceedings collects abstracts, the figures and tables, which the speakers used in their lectures. The proceedings contains two reviews from the point of view of x-ray and neutron scatterings, and six subjects (21 papers) including neutron and x-ray scattering in the era of structure genomics, structural changes detected with solution scattering, a new way in structural biology opened by neutron crystallography and neutron scattering, x-ray sources and detectors, simulation and solution scattering, and neutron sources and detectors. (Kazumata, Y.)

  16. Applied solid state science advances in materials and device research 6

    CERN Document Server

    Wolfe, Raymond

    2013-01-01

    Applied Solid State Science: Advances in Materials and Device Research, Volume 6 covers the application of composites in electronic systems. The book discusses different types of composite-composite materials consisting of finely dispersed mixtures of metals and insulators; composite devices in which two distinct semiconductor devices are combined in one package; and composite glass fibers with the core and cladding differing in their optical properties. The text describes articles dealing with properties that can be achieved in versatile materials; light-emitting diodes and photodetectors th

  17. Applied solid state science advances in materials and device research 2

    CERN Document Server

    Wolfe, Raymond

    2013-01-01

    Applied Solid State Science: Advances in Materials and Device Research, Volume 2 covers topics about complex oxide materials such as the garnets, which dominate the field of magnetoelasticity and are among the most important laser hosts, and sodalite, which is one of the classic photochromic materials. The book discusses the physics of the interactions of electromagnetic, elastic, and spin waves in single crystal magnetic insulators. The text then describes the mechanism on which inorganic photochromic materials are based, as observed in a variety of materials in single crystal, powder, and gl

  18. Passive and Active Fast-Neutron Imaging in Support of Advanced Fuel Cycle Initiative Safeguards Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Blackston, Matthew A [ORNL; Hausladen, Paul [ORNL

    2010-04-01

    Results from safeguards-related passive and active coded-aperture fast-neutron imaging measurements of plutonium and highly enriched uranium (HEU) material configurations performed at Idaho National Laboratory s Zero Power Physics Reactor facility are presented. The imaging measurements indicate that it is feasible to use fast neutron imaging in a variety of safeguards-related tasks, such as monitoring storage, evaluating holdup deposits in situ, or identifying individual leached hulls still containing fuel. The present work also presents the first demonstration of imaging of differential die away fast neutrons.

  19. Calculation And Design Of A New Configuration For Radiation Shielding At Neutron Beam No.3 For Fundamental And Applied Researches

    International Nuclear Information System (INIS)

    The tangential horizontal channel of No. 3 of the Dalat Research Reactor has been opened and used during the 1990s. The utilizations of the thermal neutron beam at this channel were the Neutron Radiography and the Prompt Gamma Neutron Activation Analysis method (PGNAA). At present, the neutron beam used for nuclear structure data researches based on the Summing of Amplitude Coincident Pulses system (SACP). Beside, several related research equipments have been set up and operated for the research purposes. A renovation of the neutron channel, therefore, will play an important role in safe and effective utilizations of the neutron beam in fields of nuclear physic training and researches. A new configuration for radiation shielding has been simulated by MCNP code. The calculated results of dose rates for neutron and gamma at working positions are in range of dose rate limit. (author)

  20. Monte Carlo calculation of ''skyshine'' neutron dose from ALS [Advanced Light Source

    International Nuclear Information System (INIS)

    This report discusses the following topics on ''skyshine'' neutron dose from ALS: Sources of radiation; ALS modeling for skyshine calculations; MORSE Monte-Carlo; Implementation of MORSE; Results of skyshine calculations from storage ring; and Comparison of MORSE shielding calculations

  1. Prospects For High Frequency Burst Searches Following Binary Neutron Star Coalescence With Advanced Gravitational Wave Detectors

    CERN Document Server

    Clark, J; Cadonati, L; Janka, H -T; Pankow, C; Stergioulas, N

    2014-01-01

    The equation of state plays a critical role in the physics of the merger of two neutron stars. Recent numerical simulations with microphysical equation of state suggest the outcome of such events depends on the mass of the neutron stars. For less massive systems, simulations favor the formation of a hypermassive, quasi-stable neutron star, whose oscillations produce a short, high frequency burst of gravitational radiation. Its dominant frequency content is tightly correlated with the radius of the neutron star, and its measurement can be used to constrain the supranuclear equation of state. In contrast, the merger of higher mass systems results in prompt gravitational collapse to a black hole. We have developed an algorithm which combines waveform reconstruction from a morphology-independent search for gravitational wave transients with Bayesian model selection, to discriminate between post-merger scenarios and accurately measure the dominant oscillation frequency. We demonstrate the efficacy of the method us...

  2. Advances in implosion physics, alternative targets design, and neutron effects on heavy ion fusion reactors

    International Nuclear Information System (INIS)

    The coupling of a new radiation transport (RT) solver with an existing multimaterial fluid dynamics code (ARWEN) using Adaptive Mesh Refinement named DAFNE, has been completed. In addition, improvements were made to ARWEN in order to work properly with the RT code, and to make it user-friendlier, including new treatment of Equations of State, and graphical tools for visualization. The evaluation of the code has been performed, comparing it with other existing RT codes (including the one used in DAFNE, but in the single-grid version). These comparisons consist in problems with real input parameters (mainly opacities and geometry parameters). Important advances in Atomic Physics, Opacity calculations and NLTE atomic physics calculations, with participation in significant experiments in this area, have been obtained. Early published calculations showed that a DTx fuel with a small tritium initial content (xe and to enhance radiation losses, reducing the plasma temperature, Ti. The neutron activation of all natural elements in First Structural Wall (FSW) component of an Inertial Fusion Energy (IFE) reactor for waste management, and the analysis of activation of target debris in NIF-type facilities has been completed. Using an original efficient modeling for pulse activation, the FSW behavior in inertial fusion has been studied. A radiological dose library coupled to the ACAB code is being generated for assessing impact of environmental releases, and atmospheric dispersion analysis from HIF reactors indicate the uncertainty in tritium release parameters. The first recognition of recombination barriers in SiC, modify the understanding of the calculation of displacement per atom, dpa, to quantify the collisional damage. An important analysis has been the confirmation, using Molecular Dynamics (MD) with an astonishing agreement, of the experimental evidence of low-temperature amorphization by damage accumulation in SiC, which could modify extensively its viability as a

  3. Advanced neutron source reactor thermal-hydraulic test loop facility description

    Energy Technology Data Exchange (ETDEWEB)

    Felde, D.K.; Farquharson, G.; Hardy, J.H.; King, J.F.; McFee, M.T.; Montgomery, B.H.; Pawel, R.E.; Power, B.H.; Shourbaji, A.A.; Siman-Tov, M.; Wood, R.J.; Yoder, G.L.

    1994-02-01

    The Thermal-Hydraulic Test Loop (THTL) is a facility for experiments constructed to support the development of the Advanced Neutron Source Reactor (ANSR) at Oak Ridge National Laboratory. The ANSR is both cooled and moderated by heavy water and uses uranium silicide fuel. The core is composed of two coaxial fuel-element annuli, each of different diameter. There are 684 parallel aluminum-clad fuel plates (252 in the inner-lower core and 432 in the outer-upper core) arranged in an involute geometry that effectively creates an array of thin rectangular flow channels. Both the fuel plates and the coolant channels are 1.27 mm thick, with a span of 87 mm (lower core), 70 mm (upper core), and 507-mm heated length. The coolant flows vertically upwards at a mass flux of 27 Mg/m{sup 2}s (inlet velocity of 25 m/s) with an inlet temperature of 45{degrees}C and inlet pressure of 3.2 MPa. The average and peak heat fluxes are approximately 6 and 12 MW/m{sup 2}, respectively. The availability of experimental data for both flow excursion (FE) and true critical heat flux (CHF) at the conditions applicable to the ANSR is very limited. The THTL was designed and built to simulate a full-length coolant subchannel of the core, allowing experimental determination of thermal limits under the expected ANSR thermal-hydraulic conditions. For these experimental studies, the involute-shaped fuel plates of the ANSR core with the narrow 1.27-mm flow gap are represented by a narrow rectangular channel. Tests in the THTL will provide both single- and two-phase thermal-hydraulic information. The specific phenomena that are to be examined are (1) single-phase heat-transfer coefficients and friction factors, (2) the point of incipient boiling, (3) nucleate boiling heat-transfer coefficients, (4) two-phase pressure-drop characteristics in the nucleate boiling regime, (5) flow instability limits, and (6) CHF limits.

  4. The neutron scattering platform of China's Advanced Research Reactor%中国先进研究堆中子散射科学平台介绍*

    Institute of Scientific and Technical Information of China (English)

    刘蕴韬; 陈东风

    2013-01-01

    As a very important method to discover the world neutron scattering technique has been applied in many fields and achieved a lot. Based on the neutron scattering facilities just built at ChinaAdvanced Research Reactor the principle and characters of this technique and facilities are intro-duced in details, and their prospected applications in the future are also described.%  中子散射技术作为人类认知世界不可或缺的独特手段,多年来在诸多领域得到了广泛应用并成绩显著。文章以新建成的中国先进研究堆中子散射科学平台谱仪为例,较为详细地介绍了中子散射技术和谱仪的基本原理和特点,并对其未来的应用进行了展望。

  5. Advanced model structures applied to system identification of a servo- hydraulic test rig

    Directory of Open Access Journals (Sweden)

    P. Czop

    2010-07-01

    Full Text Available Purpose: This paper deals with a method for the parametric system identification of a nonlinear system to obtain its parametric representation using a linear transfer function. Such representation is applicable in off-line profile correction methods minimizing the error between a reference input signal and a signal performed by the test rig. In turn, a test signal can be perfectly tracked by a servo-hydraulic test rig. This is the requirement in massive production where short test sequences are repeated to validate the products.Design/methodology/approach: A numerical and experimental case studies are presented in the paper. The numerical study presents a system identification process of a nonlinear system consisting of a linear transfer function and a nonlinear output component, being a static function. The experimental study presents a system identification process of a nonlinear system which is a servo-hydraulic test rig. The simulation data has been used to illustrate the feasibility study of the proposed approach, while the experimental data have been used to validate advanced model structures under operational conditions.Findings: The advanced model structures confirmed their better performance by means of the model fit in the time domain.Research limitations/implications: The method applies to analysis of such mechanical and hydraulic systems for which measurements are corrupted by residual harmonic disturbances resulting from system nonlinearities.Practical implications: The advanced model structures are intended to be used as inverse models in off-line signal profile correction.Originality/value: The results state the foundation for the off-line parametric error cancellation method which aims in improving tracking of load signals on servo-hydraulic test rigs.

  6. Functional renormalization group approach to neutron matter

    Directory of Open Access Journals (Sweden)

    Matthias Drews

    2014-11-01

    Full Text Available The chiral nucleon-meson model, previously applied to systems with equal number of neutrons and protons, is extended to asymmetric nuclear matter. Fluctuations are included in the framework of the functional renormalization group. The equation of state for pure neutron matter is studied and compared to recent advanced many-body calculations. The chiral condensate in neutron matter is computed as a function of baryon density. It is found that, once fluctuations are incorporated, the chiral restoration transition for pure neutron matter is shifted to high densities, much beyond three times the density of normal nuclear matter.

  7. Neutron flux variability at the TRIGA MARK II reactor, Ljubljana, as a parameter with applying the k0-method of NAA

    International Nuclear Information System (INIS)

    Neutron flux behaviour during irradiation should be known when applying the k0 method of neutron activation analysis. During two 100-hour operating periods of the TRIGA MARK II reactor, Ljubljana, the flux was measured by means of a 197Au(n,γ)198Au monitor (Eγ=411.8 keV). Cadmium-covered irradiations were also performed to obtain the epithermal flux and thermal-to-epithermal flux ratio variations. Consistency was found between these results and the reactor operators' logbook record. (author) 5 refs.; 3 figs

  8. Neutrons, deuteration and synchrotron X-rays for the study of biology and advanced materials: A match made in atoms..

    International Nuclear Information System (INIS)

    Together, the Australian Synchrotron in Melbourne and the OPAL research reactor, at the Bragg Institute in Sydney represent Australia's largest ever investment in scientific infrastructure. Both facilities commenced operation in 2007, have passed through their infancy and adolescence to take their place amongst the rank of top-flight international user facilities. Far from middle-aged, these two vibrant landmark facilities (each with 10 operational beamlines) and along with the National Deuteration Facility at ANSTO have provided transformational research capabilities for the Australian scientific community. Although modest in size compared to the well-established international competition, both institutions are producing excellent amounts of high-quality research with the Bragg Institute and the Australian Synchrotron generating more than 200 and 450 peer-reviewed publications per annum respectively. At first glance both synchrotron and neutron sources show similar scientific profiles, encompassing an extremely wide range of disciplines: materials, chemistry, biology, condensed matter physics, nanotechnology, engineering, geosciences, archaeology and studies relating to cultural heritage. Common to both are advanced capabilities for the study of atomic and molecular structure, as well as operational studies of functional materials under a diverse range of extreme environments. A more forensic examination however reveals fundamental differences in their DNA. While the biological, pharmaceutical and medical research communities drive substantial capability development and research outcomes at the Australian Synchrotron, neutron scattering and molecular deuteration at the Bragg Institute provides a focus for studies in soft condensed matter, physical and inorganic chemistry, solid state physics and crystallography. Although their respective probes are generated from different parts of the atom and interact with matter in fundamentally different ways, my

  9. An Ecological and Conservation Perspective on Advances in the Applied Virology of Zoonoses

    Directory of Open Access Journals (Sweden)

    Jonathan H. Epstein

    2011-04-01

    Full Text Available The aim of this manuscript is to describe how modern advances in our knowledge of viruses and viral evolution can be applied to the fields of disease ecology and conservation. We review recent progress in virology and provide examples of how it is informing both empirical research in field ecology and applied conservation. We include a discussion of needed breakthroughs and ways to bridge communication gaps between the field and the lab. In an effort to foster this interdisciplinary effort, we have also included a table that lists the definitions of key terms. The importance of understanding the dynamics of zoonotic pathogens in their reservoir hosts is emphasized as a tool to both assess risk factors for spillover and to test hypotheses related to treatment and/or intervention strategies. In conclusion, we highlight the need for smart surveillance, viral discovery efforts and predictive modeling. A shift towards a predictive approach is necessary in today’s globalized society because, as the 2009 H1N1 pandemic demonstrated, identification post-emergence is often too late to prevent global spread. Integrating molecular virology and ecological techniques will allow for earlier recognition of potentially dangerous pathogens, ideally before they jump from wildlife reservoirs into human or livestock populations and cause serious public health or conservation issues.

  10. Advanced in-situ measurement of soil carbon content using inelastic neutron scattering

    Science.gov (United States)

    Measurement and mapping of natural and anthropogenic variations in soil carbon stores is a critical component of any soil resource evaluation process. Emerging modalities for soil carbon analysis in the field is the registration of gamma rays from soil under neutron irradiation. The inelastic neutro...

  11. Design and layout decision for refueling system of advanced fast neutron reactors

    International Nuclear Information System (INIS)

    Describes fast neutron reactor refueling features, BN-1200 power unit general data, its refueling system design concepts, individual refueling equipment purpose and designs, and required experimental studies to create it. Refueling equipment characteristics for BN-800 and BN-1200 reactors are compared. (author)

  12. Recent advances in the study of H environments and behavior in minerals using neutron powder diffraction

    Science.gov (United States)

    Welch, M. D.

    2002-12-01

    It is now possible to probe the structural environments and behavior of H atoms directly in complex minerals such as amphiboles, micas, chlorites and humites using neutron powder diffraction, in some cases as a function of pressure and/or temperature. A combination of high neutron flux and increased detector sensitivity and size offers the chance to see details of H behaviour. In the last year or so the advent of new gasket designs for the Paris-Edinburgh pressure cell allow the use of ethanol/methanol (EtOD/MeOD) as a pressure medium, removing peak broadening arising from deviatoric stress that occurs above 3 GPa for the standard fluorinert pressure medium. Essentially hydrostatic conditions obtain with EtOD/MeOD to 8 GPa at 298 K. A further recent development has been the design of a high P-T module for use with the Paris-Edinburgh cell. These technological improvements in pressure-cell design now allow us to make meaningful correlations between OH vibrational spectra collected at high P and/or T and detailed structural information on H behaviour obtained from neutron diffraction under similar conditions. In this talk I shall discuss recent neutron diffraction experiments on the effect of pressure upon hydrogen bonding in deuterated chlorite to 5 GPa (298 K), and a high P-T study of hydrogen bonding in deuterated brucite to 7 GPa, 1100 K. These two studies illustrate how far high-pressure neutron diffraction has come in the last 5 years. Finally, I shall describe a neutron powder diffraction study (ambient conditions) of leucophoenicite, Mn7Si3O12(OH)2, a close structural analogue of Phase-B and Superhydrous-B: the structure of leucophoenicite is topologically identical to the hydrous sheet of Phase-B and similar to that of Superhydrous-B. For various reasons it was not possible to deuterate the sample. Nonetheless, the two distinct H atoms were approximately located in difference-Fourier maps and then refined isotropically. The H positions in Phase-B were only

  13. Neutron stimulated emission computed tomography applied to the assessment of calcium deposition due to the presence of microcalcifications associated with breast cancer

    International Nuclear Information System (INIS)

    In this paper we presented an application of the Neutron Stimulated Emission Computed Tomography (NSECT), which uses a thin beam of fast neutrons to stimulate stable nuclei in a sample, emitting characteristic gamma radiation. The photon energy is unique and it is used to identify the emitting nuclei. This technique was applied for evaluating the calcium isotopic composition changing due to the development of breast microcalcifications. A particular situation was simulated in which clustered microcalcifications were modeled with diameters less than 1.40 mm. In this case, neutron beam breast spectroscopy was successful in detecting the counting changes in the photon emission spectra for energies, which are characteristics of 40Ca isotope in a low deposited dose rate. (author)

  14. Neutronics analyses for fast spectrum nuclear systems and scenario studies for advanced nuclear fuel cycles

    OpenAIRE

    Grasso, Giacomo

    2010-01-01

    The present PhD thesis summarizes the three-years study about the neutronic investigation of a new concept nuclear reactor aiming at the optimization and the sustainable management of nuclear fuel in a possible European scenario. A new generation nuclear reactor for the nuclear reinassance is indeed desired by the actual industrialized world, both for the solution of the energetic question arising from the continuously growing energy demand together with the corresponding reduction of oil ava...

  15. Innovative and Advanced Coupled Neutron Transport and Thermal Hydraulic Method (Tool) for the Design, Analysis and Optimization of VHTR/NGNP Prismatic Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rahnema, Farzad; Garimeela, Srinivas; Ougouag, Abderrafi; Zhang, Dingkang

    2013-11-29

    This project will develop a 3D, advanced coarse mesh transport method (COMET-Hex) for steady- state and transient analyses in advanced very high-temperature reactors (VHTRs). The project will lead to a coupled neutronics and thermal hydraulic (T/H) core simulation tool with fuel depletion capability. The computational tool will be developed in hexagonal geometry, based solely on transport theory without (spatial) homogenization in complicated 3D geometries. In addition to the hexagonal geometry extension, collaborators will concurrently develop three additional capabilities to increase the code’s versatility as an advanced and robust core simulator for VHTRs. First, the project team will develop and implement a depletion method within the core simulator. Second, the team will develop an elementary (proof-of-concept) 1D time-dependent transport method for efficient transient analyses. The third capability will be a thermal hydraulic method coupled to the neutronics transport module for VHTRs. Current advancements in reactor core design are pushing VHTRs toward greater core and fuel heterogeneity to pursue higher burn-ups, efficiently transmute used fuel, maximize energy production, and improve plant economics and safety. As a result, an accurate and efficient neutron transport, with capabilities to treat heterogeneous burnable poison effects, is highly desirable for predicting VHTR neutronics performance. This research project’s primary objective is to advance the state of the art for reactor analysis.

  16. From nuclear structure to neutron stars

    International Nuclear Information System (INIS)

    Recent progress in quantum Monte-Carlo with modern nucleon-nucleon interactions have enabled the successful description of properties of light nuclei and neutron-rich matter. As a demonstration, we show that the agreement between theoretical calculations of the charge form factor of 12C and the experimental data is excellent. Applying similar methods to isospin-asymmetric systems allows one to describe neutrons confined in an external potential and homogeneous neutron-rich matter. Of particular interest is the nuclear symmetry energy, the energy cost of creating an isospin asymmetry. Combining these advances with recent observations of neutron star masses and radii gives insight into the equation of state of neutron-rich matter near and above the saturation density. In particular, neutron star radius measurements constrain the derivative of the symmetry energy. (authors)

  17. From nuclear structure to neutron stars

    CERN Document Server

    Gandolfi, Stefano

    2013-01-01

    Recent progress in quantum Monte Carlo with modern nucleon-nucleon interactions have enabled the successful description of properties of light nuclei and neutron-rich matter. As a demonstration, we show that the agreement between theoretical calculations of the charge form factor of 12C and the experimental data is excellent. Applying similar methods to isospin-asymmetric systems allows one to describe neutrons confined in an external potential and homogeneous neutron-rich matter. Of particular interest is the nuclear symmetry energy, the energy cost of creating an isospin asymmetry. Combining these advances with recent observations of neutron star masses and radii gives insight into the equation of state of neutron-rich matter near and above the saturation density. In particular, neutron star radius measurements constrain the derivative of the symmetry energy.

  18. Study of the characteristics of neutron monitor area applied to the evaluation of dose rates in a 15 MeV radiotherapy accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Candido M. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Fisica]. E-mail: candido_1998@yahoo.com; Patrao, Karla C.S.; Pereira, Walsan W.; Fonseca, Evaldo S.; Giannoni, Ricardo A. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Neutrons]. E-mails: karla@ird.gov.br; walsan@ird.gov.br; Batista, Delano V.S. [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil). Setor de Fisica Medica]. E-mail: delano@inca.gov.br

    2007-07-01

    Currently, in Radiotherapy, the use of linear accelerators is becoming each time more common. From Radiation Protection point of view, these instruments represent an advance in relation to the cobalt and caesium irradiators, mainly due to absence of the radioactive material. On the other hand, accelerators with the energies superior to 10 MeV produce contamination of the therapeutic beam with the presence of neutrons generated in the interaction of high-energy photons with high atomic number materials from the own irradiator. The present work carries through measurements in a linear accelerator of 15 MeV using three neutron area monitors for a comparison of the response of these instruments, evaluating its adequacy to this measurement. Characteristics of use and operation associates to parameters such as: monitor dead time, monitor gamma rejection, and calibration results are also analyzed in this study. (author)

  19. Advances on the study of air pollution in Cordoba by neutron activation analysis

    International Nuclear Information System (INIS)

    Air pollution biomonitoring has been carried out in an area of 160.000 km2 by neutron activation analysis of lichen samples (Usnea sp. and Ramalina ecklonii) in the framework of a Co-ordinated Research Programme of the IAEA and an ARCAL Technical Co-operation Project. The samples were irradiated in the RA-3 reactor and after a decay time of 6, 12 and 30 days, 24 elements (As, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Lu, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, U and Zn) were determined by gamma spectrometry. (author)

  20. Advanced sources and optical components for the McStas neutron scattering instrument simulation package

    DEFF Research Database (Denmark)

    Farhi, E.; Monzat, C.; Arnerin, R.;

    2014-01-01

    We present new McStas components Virtual_mcnp_input and Virtual_tripoli4_input, Virtual_mcnp_output and Virtual_tripoli_output to be used as interface for the MCNP and Tripoli neutron transport codes. Similarly, the new Lens component can be used to describe any refracting material set-up, includ......We present new McStas components Virtual_mcnp_input and Virtual_tripoli4_input, Virtual_mcnp_output and Virtual_tripoli_output to be used as interface for the MCNP and Tripoli neutron transport codes. Similarly, the new Lens component can be used to describe any refracting material set...... be enclosed in a scattering material in order to model the absorption and scattering in the detector housing, prior to the actual detection. An extended model of the IN5b time-of-flight spectrometer at the Institut Laue Langevin is used to simulate vanadium and powder diffractograms, making use of the gas...

  1. Neutron Albedo

    CERN Document Server

    Ignatovich, V K

    2005-01-01

    A new, algebraic, method is applied to calculation of neutron albedo from substance to check the claim that use of ultradispersive fuel and moderator of an active core can help to gain in size and mass of the reactor. In a model of isotropic distribution of incident and reflected neutrons it is shown that coherent scattering on separate grains in the case of thermal neutrons increases transport cross section negligibly, however it decreases albedo from a wall of finite thickness because of decrease of substance density. A visible increase of albedo takes place only for neutrons with wave length of the order of the size of a single grain.

  2. Dipolar structures in magnetite ferrofluids studied with small-angle neutron scattering with and without applied magnetic field

    NARCIS (Netherlands)

    Klokkenburg, M.; Erne, B.H.; Wiedenmann, A.; Petukhov, A.V.; Philipse, A.P.

    2007-01-01

    Field-induced structure formation in a ferrofluid with well-defined magnetite nanoparticles with a permanent magnetic dipole moment was studied with small-angle neutron scattering (SANS) as a function of the magnetic interactions. The interactions were tuned by adjusting the size of the well-defined

  3. Progress report on R and D results from the advanced neutron source

    International Nuclear Information System (INIS)

    This presentation consists of six parts describing the the following: Oxide Formation; U3Si2 Fuel Performance; Aluminum Irradiation Properties and Code Case; Fuel Plate Hydraulic Stability; Thermal-Hydraulic Test Loop designed to examine the CHF/flow instability limits and thermal hydraulic correlations of the ANS core; Cold Source Design Concept. HFIR results indicate good performance of U3Si2 for ANS conditions. Additional data from HFIR tests, RERTR fuel, and simulation experiments are expected to improve understanding of basic behavior. Further research plans for the cold neutron source are: Test the circulation system, Test beryllium fabricability and properties, Develop and test modified pressure-balanced cryostat, design, if possible, of safe continued operation of the reactor even if cold source refrigeration is lost

  4. Development of advanced materials for spallation neutron sources and radiation damage simulation based on multi-scale models

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Masayoshi, E-mail: masayoshi.kawai@kek.jp [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Kurishita, Hiroaki [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Kokawa, Hiroyuki [Graduate School of Engineering, Tohoku University, Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Watanabe, Seiichi; Sakaguchi, Norihito [School of Engineering, Hokkaido University, Kita-ku, Sapporo 060-8628 (Japan); Kikuchi, Kenji [Institute of Applied Beam Science, Ibaraki University, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Saito, Shigeru [J-PARC, Japan Atomic Energy Agency (JAEA), Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Yoshiie, Toshimasa [Kyoto University Research Reactor Institute, Kumatori, Sennan-gun, Osaka 590-0494 (Japan); Iwase, Hiroshi [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Ito, Takahiro [Toyohashi University of Technology, Tenpaku-cho, Toyohasi-shi, Aichi 441-8580 (Japan); Hashimoto, Satoshi; Kaneko, Yoshihisa [Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Futakawa, Masatoshi [J-PARC, Japan Atomic Energy Agency (JAEA), Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Ishino, Shiori [University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2012-12-15

    This report describes the status review of the JSPS Grant Team to develop advanced materials for the spallation neutron sources and modeling of radiation damage. One of the advanced materials is a toughness enhanced, fine-grained tungsten material (W-TiC) having four-times larger fracture toughness than ordinary tungsten and appreciable RT ductility in the recrystallized state. The other is an intergranular crack (IGC)-resistant austenitic stainless steel which was processed by the grain-boundary engineering (GBE). The experimental results are devoted to corrosion in a lead-bismuth eutectic, arrest of corrosion of weld-decay, radiation damage and creep rupture as well as new technique of GBE using a laser and annealing procedure. New technique seems to be applicable to large or complicated-shaped components. A series of the multi-scale models is built up from nuclear reaction between incident particles and medium nuclei to material property change due to radiation damage. Sample calculation is made on 3 mm-thick nickel bombarded by 3 GeV protons.

  5. Development of advanced materials for spallation neutron sources and radiation damage simulation based on multi-scale models

    Science.gov (United States)

    Kawai, Masayoshi; Kurishita, Hiroaki; Kokawa, Hiroyuki; Watanabe, Seiichi; Sakaguchi, Norihito; Kikuchi, Kenji; Saito, Shigeru; Yoshiie, Toshimasa; Iwase, Hiroshi; Ito, Takahiro; Hashimoto, Satoshi; Kaneko, Yoshihisa; Futakawa, Masatoshi; Ishino, Shiori; JSPS Grant Team

    2012-12-01

    This report describes the status review of the JSPS Grant Team to develop advanced materials for the spallation neutron sources and modeling of radiation damage. One of the advanced materials is a toughness enhanced, fine-grained tungsten material (W-TiC) having four-times larger fracture toughness than ordinary tungsten and appreciable RT ductility in the recrystallized state. The other is an intergranular crack (IGC)-resistant austenitic stainless steel which was processed by the grain-boundary engineering (GBE). The experimental results are devoted to corrosion in a lead-bismuth eutectic, arrest of corrosion of weld-decay, radiation damage and creep rupture as well as new technique of GBE using a laser and annealing procedure. New technique seems to be applicable to large or complicated-shaped components. A series of the multi-scale models is built up from nuclear reaction between incident particles and medium nuclei to material property change due to radiation damage. Sample calculation is made on 3 mm-thick nickel bombarded by 3 GeV protons.

  6. Development of advanced materials for spallation neutron sources and radiation damage simulation based on multi-scale models

    International Nuclear Information System (INIS)

    This report describes the status review of the JSPS Grant Team to develop advanced materials for the spallation neutron sources and modeling of radiation damage. One of the advanced materials is a toughness enhanced, fine-grained tungsten material (W-TiC) having four-times larger fracture toughness than ordinary tungsten and appreciable RT ductility in the recrystallized state. The other is an intergranular crack (IGC)-resistant austenitic stainless steel which was processed by the grain-boundary engineering (GBE). The experimental results are devoted to corrosion in a lead–bismuth eutectic, arrest of corrosion of weld-decay, radiation damage and creep rupture as well as new technique of GBE using a laser and annealing procedure. New technique seems to be applicable to large or complicated-shaped components. A series of the multi-scale models is built up from nuclear reaction between incident particles and medium nuclei to material property change due to radiation damage. Sample calculation is made on 3 mm-thick nickel bombarded by 3 GeV protons.

  7. Structural changes in single membranes in response to an applied transmembrane electric potential revealed by time-resolved neutron/X-ray interferometry

    International Nuclear Information System (INIS)

    Highlights: ► Time-resolved (or transient) neutron/X-ray reflectivity. ► Neutron/X-ray reflectivity enhanced by interferometric techniques. ► Electric potential induced changes in a hybrid lipid bilayer membrane. ► Electric potential induced changes in a voltage-sensor protein membrane. - Abstract: The profile structure of a hybrid lipid bilayer, tethered to the surface of an inorganic substrate and fully hydrated with a bulk aqueous medium in an electrochemical cell, was investigated as a function of the applied transbilayer electric potential via time-resolved neutron reflectivity, enhanced by interferometry. Significant, and fully reversible structural changes were observed in the distal half (with respect to the substrate surface) of the hybrid bilayer comprised of a zwitterionic phospholipid in response to a +100 mV potential with respect to 0 mV. These arise presumably due to reorientation of the electric dipole present in the polar headgroup of the phospholipid and its resulting effect on the thickness of the phospholipid’s hydrocarbon chain layer within the hybrid bilayer’s profile structure. The profile structure of the voltage-sensor domain from a voltage-gated ion channel protein within a phospholipid bilayer membrane, tethered to the surface of an inorganic substrate and fully hydrated with a bulk aqueous medium in an electrochemical cell, was also investigated as a function of the applied transmembrane electric potential via time-resolved X-ray reflectivity, enhanced by interferometry. Significant, fully-reversible, and different structural changes in the protein were detected in response to ±100 mV potentials with respect to 0 mV. The approach employed is that typical of transient spectroscopy, shown here to be applicable to both neutron and X-ray reflectivity of thin films

  8. Advanced sample environments for in situ neutron diffraction studies of nuclear materials

    Science.gov (United States)

    Reiche, Helmut Matthias

    Generation IV nuclear reactor concepts, such as the supercritical-water-cooled nuclear reactor (SCWR), are actively researched internationally. Operating conditions above the critical point of water (374°C, 22.1 MPa) and fuel core temperature that potentially exceed 1850°C put a high demand on the surrounding materials. For their safe application, it is essential to characterize and understand the material properties on an atomic scale such as crystal structure and grain orientation (texture) changes as a function of temperature and stress. This permits the refinement of models predicting the macroscopic behavior of the material. Neutron diffraction is a powerful tool in characterizing such crystallographic properties due to their deep penetration depth into condensed matter. This leads to the ability to study bulk material properties, as opposed to surface effects, and allows for complex sample environments to study e.g. the individual contributions of thermo-mechanical processing steps during manufacturing, operating or accident scenarios. I present three sample environments for in situ neutron diffraction studies that provide such crystallographic information and have been successfully commissioned and integrated into the user program of the High Pressure -- Preferred Orientation (HIPPO) diffractometer at the Los Alamos Neutron Science Center (LANSCE) user facility. I adapted a sample changer for reliable and fast automated texture measurements of multiple specimens. I built a creep furnace combining a 2700 N load frame with a resistive vanadium furnace, capable of temperatures up to 1000°C, and manipulated by a pair of synchronized rotation stages. This combination allows following deformation and temperature dependent texture and strain evolutions in situ. Utilizing the presented sample changer and creep furnace we studied pressure tubes made of Zr-2.5wt%Nb currently employed in CANDURTM nuclear reactors and proposed for future SCWRs, acting as the primary

  9. Neutron shielding material

    International Nuclear Information System (INIS)

    From among the neutron shielding materials of the 'kobesh' series developed by Kobe Steel, Ltd. for transport and storage packagings, silicon rubber base type material has been tested for several items with a view to practical application and official authorization, and in order to determine its adaptability to actual vessels. Silicon rubber base type 'kobesh SR-T01' is a material in which, from among the silicone rubber based neutron shielding materials, the hydrogen content is highest and the boron content is most optimized. Its neutron shielding capability has been already described in the previous report (Taniuchi, 1986). The following tests were carried out to determine suitability for practical application; 1) Long-term thermal stability test 2) Pouring test on an actual-scale model 3) Fire test The experimental results showed that the silicone rubber based neutron shielding material has good neutron shielding capability and high long-term fire resistance, and that it can be applied to the advanced transport packaging. (author)

  10. OSMOSE an experimental program for improving neutronic predictions of advanced nuclear fuels.

    Energy Technology Data Exchange (ETDEWEB)

    Klann, R. T.; Aliberti, G.; Zhong, Z.; Graczyk, D.; Loussi, A.; Nuclear Engineering Division; Commissariat a l Energie Atomique

    2007-10-18

    This report describes the technical results of tasks and activities conducted in FY07 to support the DOE-CEA collaboration on the OSMOSE program. The activities are divided into five high-level tasks: reactor modeling and pre-experiment analysis, sample fabrication and analysis, reactor experiments, data treatment and analysis, and assessment for relevance to high priority advanced reactor programs (such as GNEP and Gen-IV).

  11. GOLEM: a versatile computer code for reactor neutronic calculation advances in qualification of the different modules

    International Nuclear Information System (INIS)

    The last 12 years studies about the CABRI, SCARABEE and PHEBUS projects are summarized. It describes the object and the genesis of the cores, the evolution of the core concept and the associated neutronic problems. The calculational scheme used is presented, together with its qualification. The formalism, and the qualification of the different modules of GOLEM are presented. COXYS: module of physical analysis in order to determine the best energetic and spatial mesh for the case of interest. GOLU.B: input data management module. VAREC: calculation module of perturbations due to materials enables to compute perturbed flux and reactivity variation. VARYX: calculation module of geometric perturbations. TRACASYN: module of 3D power shape calculation. Finally TRACASTORE: module of management and graphic exploitation of results. Then, one gives utilization directions for these different modules. Qualification results show that GOLEM is able to analyse the fine physics of many various cases, to calculate by perturbation effects greater than 5000 pcm, to rebuild perturbed flux with margins near 3% for difficult situations, like reactor voiding or spectral or spectral variation in a PWR. Furthermore, 3D hot spots are calculated within margins of a magnitude comparable to experimental ones

  12. Study of Mechanical Features for Low Cycle Fatigue Samples of Metastable Austenitic Steel AISI 321 by Neutron Stress Analysis under Applied Load

    CERN Document Server

    Taran, Yu V; Eifler, D; Nebel, Th; Schreiber, J

    2002-01-01

    The elastoplastic properties of the austenitic matrix and martensitic volume areas induced during cyclic tensile-compressive loading of low carbon metastable austenitic stainless steel were studied in an in situ neutron diffraction stress rig experiment on the ENGIN instrument at the ISIS pulsed neutron facility. Samples prepared from the steel AISI 321 annealed at 1050 ^{\\circ}C and quenched in water were subjected to low-cycle fatigue under total-strain control with an amplitude of 1 % at a frequency of 0.5 Hz. Subsequent applied stress?elastic strain responses of the austenitic and martensitic phases were obtained by Rietveld and Le Bail refinements of the neutron diffraction spectra, and were used to determine the elastic constants of the phases as a function of fatigue level. The results of modified refinements accounting for the elastic anisotropy in polycrystalline materials under load are also presented. The residual strains in the austenitic matrix were determined as a function of fatigue cycling, us...

  13. Materials research with neutron beams from a research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Root, J.; Banks, D. [Canadian Neutron Beam Centre, Chalk River Laboratories, Chalk River, Ontario (Canada)

    2015-03-15

    Because of the unique ways that neutrons interact with matter, neutron beams from a research reactor can reveal knowledge about materials that cannot be obtained as easily with other scientific methods. Neutron beams are suitable for imaging methods (radiography or tomography), for scattering methods (diffraction, spectroscopy, and reflectometry) and for other possibilities. Neutron-beam methods are applied by students and researchers from academia, industry and government to support their materials research programs in several disciplines: physics, chemistry, materials science and life science. The arising knowledge about materials has been applied to advance technologies that appear in everyday life: transportation, communication, energy, environment and health. This paper illustrates the broad spectrum of materials research with neutron beams, by presenting examples from the Canadian Neutron Beam Centre at the NRU research reactor in Chalk River. (author)

  14. Neutron activation analysis applied to the study of heavy metal marine pollution observed through bioaccumulation in macroscopic algae near El Jadida, Morocco

    International Nuclear Information System (INIS)

    The heavy metals bio-accumulation ability of algae was studied along the North Atlantic Morrocan coast. Instrumental neutron activation analysis was used, to determine concentrations of various elements. The k0 standardization method was used. Some interferences corrections, particularly due to high concentrations of uranium were applied. The quality of the method was checked by using the CRM 140, a Fucus provided by IAEA. Important pollutions appear for several heavy metals from the Morrocan phosphate industry, with respect to the natural background environment. (author)

  15. Advanced automation concepts applied to Experimental Breeder Reactor-II startup

    International Nuclear Information System (INIS)

    The major objective of this work is to demonstrate through simulations that advanced liquid-metal reactor plants can be operated from low power by computer control. Development of an automatic control system with this objective will help resolve specific issues and provide proof through demonstration that automatic control for plant startup is feasible. This paper presents an advanced control system design for startup of the Experimental Breeder Reactor-2 (EBR-2) located at Idaho Falls, Idaho. The design incorporates recent methods in nonlinear control with advanced diagnostics techniques such as neural networks to form an integrated architecture. The preliminary evaluations are obtained in a simulated environment by a low-order, valid nonlinear model. Within the framework of phase 1 research, the design includes an inverse dynamics controller, a fuzzy controller, and an artificial neural network controller. These three nonlinear control modules are designed to follow the EBR-2 startup trajectories in a multi-input/output regime. They are coordinated by a supervisory routine to yield a fault-tolerant, parallel operation. The control system operates in three modes: manual, semiautomatic, and fully automatic control. The simulation results of the EBR-2 startup transients proved the effectiveness of the advanced concepts. The work presented in this paper is a preliminary feasibility analysis and does not constitute a final design of an automated startup control system for EBR-2. 14 refs., 43 figs

  16. A SURVEY OF THE PARAMETER SPACE OF THE COMPRESSIBLE LIQUID DROP MODEL AS APPLIED TO THE NEUTRON STAR INNER CRUST

    Energy Technology Data Exchange (ETDEWEB)

    Newton, W. G.; Gearheart, M.; Li Baoan, E-mail: william.newton@tamuc.edu [Department of Physics and Astronomy, Texas A and M University-Commerce, Commerce, TX 75429-3011 (United States)

    2013-01-15

    We present a systematic survey of the range of predictions of the neutron star inner crust composition, crust-core transition densities and pressures, and density range of the nuclear 'pasta' phases at the bottom of the crust provided by the compressible liquid drop model in light of the current experimental and theoretical constraints on model parameters. Using a Skyrme-like model for nuclear matter, we construct baseline sequences of crust models by consistently varying the density dependence of the bulk symmetry energy at nuclear saturation density, L, under two conditions: (1) that the magnitude of the symmetry energy at saturation density J is held constant, and (2) J correlates with L under the constraint that the pure neutron matter (PNM) equation of state (EoS) satisfies the results of ab initio calculations at low densities. Such baseline crust models facilitate consistent exploration of the L dependence of crustal properties. The remaining surface energy and symmetric nuclear matter parameters are systematically varied around the baseline, and different functional forms of the PNM EoS at sub-saturation densities implemented, to estimate theoretical 'error bars' for the baseline predictions. Inner crust composition and transition densities are shown to be most sensitive to the surface energy at very low proton fractions and to the behavior of the sub-saturation PNM EoS. Recent calculations of the energies of neutron drops suggest that the low-proton-fraction surface energy might be higher than predicted in Skyrme-like models, which our study suggests may result in a greatly reduced volume of pasta in the crust than conventionally predicted.

  17. Study on void fraction distribution in the moderator cell of Cold Neutron Source systems in China Advanced Research Reactor

    Science.gov (United States)

    Li, Liangxing; Li, Huixiong; Hu, Jinfeng; Bi, Qincheng; Chen, Tingkuan

    2007-04-01

    A physical model is developed for analyzing and evaluating the void fraction profiles in the moderator cell of the Cold Neutron Source (CNS) of the China Advanced Research Reactor (CARR), which is now constructing in the China Institute of Atomic Energy (CIAE). The results derived from the model are compared with the related experimental data and its propriety is verified. The model is then used to explore the influence of various factors, including the diameter of boiling vapor bubbles, liquid density, liquid viscosity and the total heating power acted on the moderator cell, on the void fraction profiles in the cell. The results calculated with the present model indicate that the void fraction in the moderator cell increases linearly with heating power, and increases with the liquid viscosity, but decreases as the size of bubbles increases, and increases linearly with heating power. For the case where hydrogen is being used as a moderator, calculation results show that the void fraction in the moderator cell may be less than 30%, which is the maximum void fraction permitted from the nuclear physics point of view. The model and the calculation results will help to obtain insight of the mechanism that controls the void fraction distribution in the moderator cell, and provide theoretical supports for the moderator cell design.

  18. Analyses of the reflector tank, cold source, and beam tube cooling for ANS reactor. [Advanced Neutron Source (ANS)

    Energy Technology Data Exchange (ETDEWEB)

    Marland, S. (Tennessee Univ., Knoxville, TN (United States))

    1992-07-01

    This report describes my work as an intern with Martin Marietta Energy Systems, Inc., in the summer of 1991. I was assigned to the Reactor Technology Engineering Department, working on the Advanced Neutron Source (ANS). My first project was to select and analyze sealing systems for the top of the diverter/reflector tank. This involved investigating various metal seals and calculating the forces necessary to maintain an adequate seal. The force calculations led to an analysis of several bolt patterns and lockring concepts that could be used to maintain a seal on the vessel. Another project involved some pressure vessel stress calculations and the calculation of the center of gravity for the cold source assembly. I also completed some sketches of possible cooling channel patterns for the inner vessel of the cold source. In addition, I worked on some thermal design analyses for the reflector tank and beam tubes, including heat transfer calculations and assisting in Patran and Pthermal analyses. To supplement the ANS work, I worked on other projects. I completed some stress/deflection analyses on several different beams. These analyses were done with the aid of CAASE, a beam-analysis software package. An additional project involved bending analysis on a carbon removal system. This study was done to find the deflection of a complex-shaped beam when loaded with a full waste can.

  19. Heavy Neutron Irradiation Test of Materials in Joyo Instrumented Rigs

    International Nuclear Information System (INIS)

    For studies of radiation effects in materials for advanced nuclear systems including a nuclear fusion reactor, heavy neutron irradiation by high energy neutrons is essential. A sodium cooled high flux fast reactor will be only a choice for realizing heavy neutron irradiation. The paper will describe the brief history of radiation effects study utilizing fission reactors in Japan, and the status of the fast reactor of JOYO in Japan, for applying it to the heavy irradiation of candidate materials for advanced nuclear systems. (author)

  20. Applying full multigroup cell characteristics from MCU code to finite difference calculations of neutron field in VVER core

    Energy Technology Data Exchange (ETDEWEB)

    Gorodkov, S.S.; Kalugin, M.A. [Nuclear Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation)

    2015-09-15

    Up to now core calculations with Monte Carlo provided only average cross-sections of mesh cells for further use either in finite difference calculations or as benchmark ones for approximate spectral algorithms. Now MCU code is capable to handle functions, which may be interpreted as average diffusion coefficients. Subsequently the results of finite difference calculations with cells characteristic sets obtained in such a way can be compared with Monte Carlo results as benchmarks, giving reliable information on quality of production code under consideration. As an example of such analysis, the results of mesh calculations with 1-, 2-, 4-, 8- and 12 neutron groups of some model VVER fuel assembly are presented in comparison with the exact Monte Carlo solution. As a second example, an analysis is presented of water gap approximate enlargement between fuel assemblies, allowing VVER core region be covered by regular mesh.

  1. Design and layout decisions for refuelling system of advanced fast neutron reactor

    International Nuclear Information System (INIS)

    The experience in operation of BOR-60, BN-350 and BN-600 power units, as well as development of refuelling systems for BN-800 power unit, allows developing of refuelling system for BN-1200 advanced reactor of new generation. The refuelling system was developed on the basis of possible technical decisions aimed at improvement of safety and technical-and-economic indices. Structural layout of BN-1200 reactor refuelling system is given. Main differences in BN-1200 reactor refuelling system as compared with BN-800 reactor are given. Design features of refuelling equipment are: - BN-1200 reactor has a split large rotating plug to allow transporting of its components by railway with subsequent assembling at site; - the refuelling box is fabricated in the form of sectional parallelepiped to allow transporting of its components by railway with subsequent assembling at site; - one 'direct' refuelling mechanism and one cantilever' refuelling mechanism are used to refuel rarely replaced protection assemblies that allows reducing of overall dimensions of rotating plugs; - the vertical elevator is arranged on the oval plug installed on the reactor cover. The upper structure with elevator drive rotates together with the elevator plug under rotary drive located on the oval plug. The vertical elevator allows sufficient reduction of refuelling box; - the refuelling machine runs on straight-line rails. The vertical elevator, gas gate valve on reactor refuelling channel, non-use of spent FA drum and enhanced radiation protection on the column of refuelling box machine allows reduction of specific materials consumption of BN-1200 reactor refuelling system by more than 10 times as compared with BN-800 reactor. To verify refuelling equipment operability the following experiments are planned: - mastering of gripper design for 'direct' refuelling mechanism and refuelling machine; - mastering of 'cantilever' for refuelling mechanism; - mastering of fresh FA conveyor design. As for the

  2. Advanced robotics technology applied to mixed waste characterization, sorting and treatment

    International Nuclear Information System (INIS)

    There are over one million cubic meters of radioactively contaminated hazardous waste, known as mixed waste, stored at Department of Energy facilities. Researchers at Lawrence Livermore National Laboratory (LLNL) are developing methods to safely and efficiently treat this type of waste. LLNL has automated and demonstrated a means of segregating items in a mixed waste stream. This capability incorporates robotics and automation with advanced multi-sensor information for autonomous and teleoperational handling of mixed waste items with previously unknown characteristics. The first phase of remote waste stream handling was item singulation; the ability to remove individual items of heterogeneous waste directly from a drum, box, bin, or pile. Once objects were singulated, additional multi-sensory information was used for object classification and segregation. In addition, autonomous and teleoperational surface cleaning and decontamination of homogeneous metals has been demonstrated in processing mixed waste streams. The LLNL waste stream demonstration includes advanced technology such as object classification algorithms, identification of various metal types using active and passive gamma scans and RF signatures, and improved teleoperational and autonomous grasping of waste objects. The workcell control program used an off-line programming system as a server to perform both simulation control as well as actual hardware control of the workcell. This paper will discuss the motivation for remote mixed waste stream handling, the overall workcell layout, sensor specifications, workcell supervisory control, 3D vision based automated grasp planning and object classification algorithms

  3. Advanced robotics technology applied to mixed waste characterization, sorting and treatment

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelmsen, K.; Hurd, R.; Grasz, E.

    1994-04-01

    There are over one million cubic meters of radioactively contaminated hazardous waste, known as mixed waste, stored at Department of Energy facilities. Researchers at Lawrence Livermore National Laboratory (LLNL) are developing methods to safely and efficiently treat this type of waste. LLNL has automated and demonstrated a means of segregating items in a mixed waste stream. This capability incorporates robotics and automation with advanced multi-sensor information for autonomous and teleoperational handling of mixed waste items with previously unknown characteristics. The first phase of remote waste stream handling was item singulation; the ability to remove individual items of heterogeneous waste directly from a drum, box, bin, or pile. Once objects were singulated, additional multi-sensory information was used for object classification and segregation. In addition, autonomous and teleoperational surface cleaning and decontamination of homogeneous metals has been demonstrated in processing mixed waste streams. The LLNL waste stream demonstration includes advanced technology such as object classification algorithms, identification of various metal types using active and passive gamma scans and RF signatures, and improved teleoperational and autonomous grasping of waste objects. The workcell control program used an off-line programming system as a server to perform both simulation control as well as actual hardware control of the workcell. This paper will discuss the motivation for remote mixed waste stream handling, the overall workcell layout, sensor specifications, workcell supervisory control, 3D vision based automated grasp planning and object classification algorithms.

  4. A High Temperature-Tolerant and Radiation-Resistant In-Core Neutron Sensor for Advanced Reactors. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Lei [The Ohio State Univ., Columbus, OH (United States); Miller, Don [The Ohio State Univ., Columbus, OH (United States)

    2015-01-23

    The objectives of this project are to develop a small and reliable gallium nitride (GaN) neutron sensor that is capable of withstanding high neutron fluence and high temperature, isolating gamma background, and operating in a wide dynamic range. The first objective will be the understanding of the fundamental materials properties and electronic response of a GaN semiconductor materials and device in an environment of high temperature and intense neutron field. To achieve such goal, an in-situ study of electronic properties of GaN device such as I-V, leakage current, and charge collection efficiency (CCE) in high temperature using an external neutron beam will be designed and implemented. We will also perform in-core irradiation of GaN up to the highest yet fast neutron fluence and an off-line performance evaluation.

  5. Advanced transformational analysis applied to e-beam proximity effect correction

    Science.gov (United States)

    Barouch, Eytan; Coifman, Ronald R.; Ma, Jimmy T.; Peckerar, Martin C.; Rokhlin, Vladimir

    1993-06-01

    In this paper we address the problem of dose correction in the data bases consistent with ultra- large-scale integration. It is shown that recent advances in transformation theory provide a natural platform on which to build these dose correctors. Specifically, transformation approaches making use of compactly supported, smooth basis functions are shown to be particularly suitable. This is a natural result of the evolution of mathematically based correctors currently in use. Previous work in Parikh, MacDonald and others employed global transform method to determine the values of 'corrected' dose. In most cases, the mathematical inversion is essentially ill posed, in other words, the exact pattern desired cannot be obtained using a finite Gaussian sum. In this paper a set of smooth basis elements of compact support are employed. The mathematically smooth form of the basis makes it easy to match doses at boundaries without Gibbs phenomenon. Thus the transform field can be partitioned for optimum speed. Consequently, while most transformation complexities are of order N6 (the inversion of an N2 X N2 matrix) where N2 is the number of grid points characterizing the database, we developed an algorithm of complexity N2 log N. A method of dose field bias is employed to stem the requests for negative dose. The heart of the numerical process is essentially based on an adapted fast non-uniform-grid Fourier Transform combined with proper filtering and geometric localization methods. Several examples are given.

  6. Applying advanced imaging techniques to a murine model of orthotopic osteosarcoma

    Directory of Open Access Journals (Sweden)

    Matthew Lawrence Broadhead

    2015-08-01

    Full Text Available IntroductionReliable animal models are required to evaluate novel treatments for osteosarcoma. In this study, the aim was to implement advanced imaging techniques in a murine model of orthotopic osteosarcoma to improve disease modeling and the assessment of primary and metastatic disease.Materials and methodsIntra-tibial injection of luciferase-tagged OPGR80 murine osteosarcoma cells was performed in Balb/c nude mice. Treatment agent (pigment epithelium-derived factor; PEDF was delivered to the peritoneal cavity. Primary tumors and metastases were evaluated by in vivo bioluminescent assays, micro-computed tomography, [18F]-Fluoride-PET and [18F]-FDG-PET. Results[18F]-Fluoride-PET was more sensitive than [18F]-FDG-PET for detecting early disease. Both [18F]-Fluoride-PET and [18F]-FDG-PET showed progressive disease in the model, with 4-fold and 2-fold increases in SUV (p<0.05 by the study endpoint, respectively. In vivo bioluminescent assay showed that systemically delivered PEDF inhibited growth of primary osteosarcoma.DiscussionApplication of [18F]-Fluoride-PET and [18F]-FDG-PET to an established murine model of orthotopic osteosarcoma has improved the assessment of disease. The use of targeted imaging should prove beneficial for the evaluation of new approaches to osteosarcoma therapy.

  7. In Situ Characterization Techniques Based on Synchrotron Radiation and Neutrons Applied for the Development of an Engineering Intermetallic Titanium Aluminide Alloy

    Directory of Open Access Journals (Sweden)

    Petra Erdely

    2016-01-01

    Full Text Available Challenging issues concerning energy efficiency and environmental politics require novel approaches to materials design. A recent example with regard to structural materials is the emergence of lightweight intermetallic TiAl alloys. Their excellent high-temperature mechanical properties, low density and high stiffness constitute a profile perfectly suitable for their application as advanced aero-engine turbine blades or as turbocharger turbine wheels in next-generation automotive engines. As the properties of TiAl alloys during processing as well as during service are dependent on the phases occurring, detailed knowledge of their volume fractions and distribution within the microstructure is of paramount importance. Furthermore, the behavior of the individual phases during hot deformation and subsequent heat treatments is of interest to define reliable and cost-effective industrial production processes. In situ high-energy X-ray diffraction methods allow tracing the evolution of phase fractions over a large temperature range. Neutron diffraction unveils information on order-disorder transformations in TiAl alloys. Small-angle scattering experiments offer insights into the materials’ precipitation behavior. This review attempts to shine a light on selected in situ diffraction and scattering techniques and the ways in which they promoted the development of an advanced engineering TiAl alloy.

  8. Advanced lasers laser physics and technology for applied and fundamental science

    CERN Document Server

    Sukhoivanov, Igor

    2015-01-01

    Presenting a blend of applied and fundamental research in highly interdisciplinary subjects of rapidly developing areas, this book contains contributions on the frontiers and hot topics of laser physics, laser technology and laser engineering, and covers a wide range of laser topics, from all-optical signal processing and chaotic optical communication to production of superwicking surfaces, correction of extremely high-power beams, and generation of ultrabroadband spectra. It presents both review-type contributions and well researched and documented case studies, and is intended for graduate students, young scientist, and emeritus scientist working/studying in laser physics, optoelectronics, optics, photonics, and adjacent areas. The book contains both experimental and theoretical studies, as well as combinations of these two, which is known to be a most useful and interesting form of reporting scientific results, allowing students to really learn from each contribution. The book contains over 130 illustratio...

  9. The Path to Sustainable Nuclear Energy. Basic and Applied Research Opportunities for Advanced Fuel Cycles, September 12-14, 2005

    International Nuclear Information System (INIS)

    The objective of this report is to identify new basic science that will be the foundation for advances in nuclear fuel-cycle technology in the near term, and for changing the nature of fuel cycles and of the nuclear energy industry in the long term. The goals are to enhance the development of nuclear energy, to maximize energy production in nuclear reactor parks, and to minimize radioactive wastes, other environmental impacts, and proliferation risks. The limitations of the once-through fuel cycle can be overcome by adopting a closed fuel cycle, in which the irradiated fuel is reprocessed and its components are separated into streams that are recycled into a reactor or disposed of in appropriate waste forms. The recycled fuel is irradiated in a reactor, where certain constituents are partially transmuted into heavier isotopes via neutron capture or into lighter isotopes via fission. Fast reactors are required to complete the transmutation of long-lived isotopes. Closed fuel cycles are encompassed by the Department of Energy?s Advanced Fuel Cycle Initiative (AFCI), to which basic scientific research can contribute. Two nuclear reactor system architectures can meet the AFCI objectives: a ?single-tier? system or a ?dual-tier? system. Both begin with light water reactors and incorporate fast reactors. The ?dual-tier? systems transmute some plutonium and neptunium in light water reactors and all remaining transuranic elements (TRUs) in a closed-cycle fast reactor. Basic science initiatives are needed in two broad areas: ? Near-term impacts that can enhance the development of either ?single-tier? or ?dual-tier? AFCI systems, primarily within the next 20 years, through basic research. Examples: Dissolution of spent fuel, separations of elements for TRU recycling and transmutation Design, synthesis, and testing of inert matrix nuclear fuels and non-oxide fuels Invention and development of accurate on-line monitoring systems for chemical and nuclear species in the nuclear

  10. Studies on application of neutron activation analysis -Applied research on air pollution monitoring and development of analytical method of environmental samples

    International Nuclear Information System (INIS)

    This research report is written for results of applied research on air pollution monitoring using instrumental neutron activation analysis. For identification and standardization of analytical method, 24 environmental samples are analyzed quantitatively, and accuracy and precision of this method are measured. Using airborne particulate matter and biomonitor chosen as environmental indicators, trace elemental concentrations of sample collected at urban and rural site monthly are determined ant then the calculation of statistics and the factor analysis are carried out for investigation of emission source. Facilities for NAA are installed in a new HANARO reactor, functional test is performed for routine operation. In addition, unified software code for NAA is developed to improve accuracy, precision and abilities of analytical processes. (author). 103 refs., 61 tabs., 19 figs

  11. DANCE (Detector for Advanced Neutron Capture Experiments) is a 4π array of BaF2 crystals installed at LANSCE, Lujan Center. Neutron capture measurements on ^157Gd and ^89Y nuclei were conducted using this facility.

    Science.gov (United States)

    Chyzh, A.; Mitchell, G.; Vieira, D.; Bredeweg, T.; Ullmann, J.; Jandel, M.; Couture, A.; Keksis, A.; Rundberg, R.; Wilhelmy, J.; O'Donnell, J.; Baramsai, B.; Haight, R.; Wouters, J.; Krticka, M.; Parker, W.; Becker, J.; Agvaanlusan, U.

    2009-10-01

    DANCE (Detector for Advanced Neutron Capture Experiments) is a 4π array of BaF2 crystals installed at LANSCE, Lujan Center. Neutron capture measurements on ^157Gd and ^89Y nuclei were conducted using this facility. The absolute cross sections of the ^89Y(n,γ) reaction was measured for the first time ever in the neutron energy range of 10 eV -- 10 keV and improvements were made in the 10 -- 300 keV range. The error bars were significantly reduced and number of cross section points was increased since the past ^89Y(n,γ) experiments. The ^157Gd(n,γ) cross section was determined at En = 20 eV -- 300 keV by normalizing the experimental DANCE data to a well known resonance taken from the ENDF/B-VII library. Computer simulations of the ^157Gd(n,γ) cascades and DANCE pulse height function were made using DICEBOX and GEANT4 codes and simulated Esum and Eγ spectra are compared to the experimental DANCE data. Values of spin and photon strength function (PSF) of the ^157Gd(n,γ) resonances are provided in the range of En = 2 -- 300 eV using spin dependence upon a γ-ray multiplicity.

  12. Systematic and statistical errors in a bayesian approach to the estimation of the neutron-star equation of state using advanced gravitational wave detectors

    CERN Document Server

    Wade, Leslie; Ochsner, Evan; Lackey, Benjamin D; Farr, Benjamin F; Littenberg, Tyson B; Raymond, Vivien

    2014-01-01

    Advanced ground-based gravitational-wave detectors are capable of measuring tidal influences in binary neutron-star systems. In this work, we report on the statistical uncertainties in measuring tidal deformability with a full Bayesian parameter estimation implementation. We show how simultaneous measurements of chirp mass and tidal deformability can be used to constrain the neutron-star equation of state. We also study the effects of waveform modeling bias and individual instances of detector noise on these measurements. We notably find that systematic error between post-Newtonian waveform families can significantly bias the estimation of tidal parameters, thus motivating the continued development of waveform models that are more reliable at high frequencies.

  13. Advanced examination techniques applied to the qualification of critical welds for the ITER correction coils

    CERN Document Server

    Sgobba, Stefano; Libeyre, Paul; Marcinek, Dawid Jaroslaw; Piguiet, Aline; Cécillon, Alexandre

    2015-01-01

    The ITER correction coils (CCs) consist of three sets of six coils located in between the toroidal (TF) and poloidal field (PF) magnets. The CCs rely on a Cable-in-Conduit Conductor (CICC), whose supercritical cooling at 4.5 K is provided by helium inlets and outlets. The assembly of the nozzles to the stainless steel conductor conduit includes fillet welds requiring full penetration through the thickness of the nozzle. Static and cyclic stresses have to be sustained by the inlet welds during operation. The entire volume of helium inlet and outlet welds, that are submitted to the most stringent quality levels of imperfections according to standards in force, is virtually uninspectable with sufficient resolution by conventional or computed radiography or by Ultrasonic Testing. On the other hand, X-ray computed tomography (CT) was successfully applied to inspect the full weld volume of several dozens of helium inlet qualification samples. The extensive use of CT techniques allowed a significant progress in the ...

  14. Advanced Penning-type ion source development and passive beam focusing techniques for an associated particle imaging neutron generator

    OpenAIRE

    Sy, Amy

    2013-01-01

    The use of accelerator-based neutron generators for non-destructive imaging and analysis in commercial and security applications is continuously under development, with improvements to available systems and combinations of available techniques revealing new capabilities for real-time elemental and isotopic analysis. The recent application of associated particle imaging (API) techniques for time- and directionally-tagged neutrons to induced fission and transmission imaging methods demonstrate...

  15. A new formulation of the pseudocontinuous synthesis algorithm applied to the calculation of neutronic flux in PWR reactors

    International Nuclear Information System (INIS)

    A new formulation of the pseudocontinuous synthesis algorithm is applied to solve the static three dimensional two-group diffusion equations. The new method avoids ambiguities regarding interface conditions, which are inherent to the differential formulation, by resorting to the finite difference version of the differential equations involved. A considerable number of input/output options, possible core configurations and control rod positioning are implemented resulting in a very flexible as well as economical code to compute 3D fluxes, power density and reactivities of PWR reactors with partial inserted control rods. The performance of this new code is checked against the IAEA 3D Benchmark problem and results show that SINT3D yields comparable accuracy with much less computing time and memory required than in conventional 3D finite differerence codes. (Author)

  16. Applying the Skill-Rule-Knowledge Framework to Understanding Operators’ Behaviors and Workload in Advanced Main Control Rooms

    International Nuclear Information System (INIS)

    Highlights: • Operator behaviors were analyzed according to Rasmussen's SRK classification. • Different job positions connote different abilities to perform the job successfully. • Rule-based behavior comprised the main behavior patterns of the operating crew. - Abstract: For the past years, a number of researches have focused on operators’ behaviors and workloads in advanced main control rooms (MCRs) in either the procedure-domain or knowledge-domain and in either workload-increased or workload-decreased conditions. Different job positions connote different responsibilities and abilities that are required to perform the job successfully. However, it may be inappropriate to apply a dichotomy in these issues. In this study, we clarified these controversial points through the analysis of the time, frequency, and workload of the behaviors based on Rasmussen's skill–rule–knowledge classification (SRK framework) according to the supervisor operator (SRO), reactor operator (RO), and assistant reactor operator (ARO). The results showed that, for the SRO, rule- and knowledge-based behaviors occurred more often than skill-based behavior in terms of time and frequency, and knowledge-based behavior was the main source of workload. For the RO, no significant differences were found among the three behavior types in terms of frequency and workload, but more time was spent on rule-based behaviors than on skill- and knowledge-based behaviors. The ARO spent more time performing skill-based behaviors than rule- and knowledge-based behaviors, but in terms of frequency and workload, rule-based behavior was the predominant type. Operators’ behaviors contribute to a plant's defense-in-depth approach to safety and serve a vital function in ensuring its safe operation. Research on behavioral taxonomies of advanced MCRs has many significant benefits in both scientific-theoretical and applied practical fields

  17. Basic neutronics. Neutrons migration

    International Nuclear Information System (INIS)

    This article presents the basic neutronics necessary for the understanding of the operation of the different types of nuclear reactors: 1 - introduction to neutronics: principle of fission chain reactions, fast neutron reactors and thermal neutron reactors, capture, neutron status, variations with the reactor lattices; 2 - Boltzmann equation: neutrons population, neutrons migration, characterization of neutrons population and reactions, integral form of the Boltzmann equation, integral-differential form, equivalence between the two forms; 3 - reactor kinetics: fast neutrons and delayed neutrons, kinetic equations in punctual model, Nordheim equation, reactivity jumps, reactivity ramp; 4 - diffusion equation: local neutron status, Fick's law, diffusion equation, initial, boundary and interface conditions, nuclei in infinite and homogenous medium, some examples of solutions, developments in Eigenmodes; 5 - one-group theory: equation of the 'one-group - diffusion' theory, critical condition of the naked and homogenous reactor, critical condition of a reactor with reflectors, generalizations; 6 - neutrons moderation: different moderation mechanisms, elastic shock laws, moderation equation, some examples of solutions; 7 - resonance absorption of neutrons: advantage of the discontinuous moderation character, advantage of an heterogenous disposition, classical formula of the anti-trap factor in homogenous and heterogenous situation; 8 - neutrons thermalization: notions of thermalization mechanisms, thermalization equation, Maxwell spectrum, real spectrum, classical formula of the thermal utilisation factor, classical formula of the reproduction factor, moderation optimum. (J.S.)

  18. Detailed heat load calculations at the beginning, middle, and end of cycle for the conceptual design of the Advanced Neutron Source Reactor

    International Nuclear Information System (INIS)

    The Advanced Neutron Source (ANS) is a world-class research reactor and experimental center for neutron research, presently being designed at the Oak Ridge National Laboratory (ORNL). The reactor consists of a 330-MW(f) highly enriched uranium core, which is cooled, moderated, and reflected with heavy water. When completed, it will be the preeminent ultrahigh neutron flux reactor in the world, with facilities for research programs in biology, materials science, chemistry, fundamental and nuclear physics, and analytical chemistry. Irradiation facilities are provided for a variety of isotope production capabilities, as well as materials irradiation. The ANS reactor design, at the time of this report, has completed the conceptual design phase and entered the advanced conceptual design phase. This report is part of an effort to fully document the analysis methods and results for the conceptual design. It details the methods used to perform heat load calculations on the ANS reactor design, describes the model used, and gives the resulting heat loads in all components of the reactor, in both a differential (by segment) and integral (by component) fashion. These heat load data are provided at three times within the ANS fuel cycle - at beginning (0 days), middle (8.5 days), and end (17 days) of cycle. The remainder of the report is dedicated to this description. In Chapter 2, some necessary background on the reactor design is provided. Chapters 3 and 4 give details of the depletion methods used and revisions to previous MCNP models. Chapter 5 analyzes the results of these calculations, and Chapter 6 provides a summary and conclusions

  19. A Quantitative Feasibility Study on Potential Safety Improvement Effects of Advanced Safety Features in APR-1400 when Applied to OPR-1000

    Energy Technology Data Exchange (ETDEWEB)

    Ualikhan Zhiyenbayev [KAIST, Daejeon (Korea, Republic of); Chung, Dae Wook [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    This study aims to test the feasibility of the applications using Probabilistic Safety Assessment (PSA). Particularly, three of those advanced safety features are selected as follows: 1. Providing an additional Emergency Diesel Generator (EDG); 2. Increasing the capacity of Class 1E batteries; 3. Placing a Refueling Water Storage Tank (RWST) inside containment, i.e., change from RWST to IRWST. The Advanced Power Reactor 1400 (APR-1400) adopts several advanced safety features compared to its predecessor, the Optimized Power Reactor 1000 (OPR-1000), which includes an additional Emergency Diesel Generator, increase in battery capacity, in-containment refueling water storage tank (IRWST), and so on. Considering the remarkable advantages of these safety features in safety improvement and the design similarities between APR-1400 and OPR-1000, it is feasible to apply key advanced safety features of APR-1400 to OPR-1000 to enhance the safety. The selected safety features are incorporated into OPR-1000 PSA model using the Advanced Information Management System (AIMS) for PSA and CDFs are re-evaluated for each application and combination of three applications. Based on current results, it is concluded that three of key advanced safety features of APR-1400 can be effectively applied to OPR-1000, resulting in considerable safety improvement. In aggregate, three advanced safety features, which are an additional EDG, increased battery capacity and IRWST, can reduce the CDF of OPR-1000 by more than 15% when applied altogether.

  20. Isotopic neutron sources for neutron activation analysis

    International Nuclear Information System (INIS)

    This User's Manual is an attempt to provide for teaching and training purposes, a series of well thought out demonstrative experiments in neutron activation analysis based on the utilization of an isotopic neutron source. In some cases, these ideas can be applied to solve practical analytical problems. 19 refs, figs and tabs

  1. Neutronic of heterogenous gas cooled reactors

    International Nuclear Information System (INIS)

    At present, one of the main technical features of the advanced gas cooled reactor under development is its fuel element concept, which implies a neutronic homogeneous design, thus requiring higher enrichment compared with present commercial nuclear power plants.In this work a neutronic heterogeneous gas cooled reactor design is analyzed by studying the neutronic design of the Advanced Gas cooled Reactor (AGR), a low enrichment, gas cooled and graphite moderated nuclear power plant.A search of merit figures (some neutronic parameter, characteristic dimension, or a mixture of both) which are important and have been optimized during the reactor design stage is been done, to aim to comprise how a gas heterogeneous reactor is been design, given that semi-infinity arrangement criteria of rods in LWRs and clusters in HWRs can t be applied for a solid moderator and a gas refrigerator.The WIMS code for neutronic cell calculations is been utilized to model the AGR fuel cell and to calculate neutronic parameters such as the multiplication factor and the pick factor, as function of the fuel burnup.Also calculation is been done for various nucleus characteristic dimensions values (fuel pin radius, fuel channel pitch) and neutronic parameters (such as fuel enrichment), around the design established parameters values.A fuel cycle cost analysis is carried out according to the reactor in study, and the enrichment effect over it is been studied.Finally, a thermal stability analysis is been done, in subcritical condition and at power level, to study this reactor characteristic reactivity coefficients.Present results shows (considering the approximation used) a first set of neutronic design figures of merit consistent with the AGR design.

  2. Uses of advanced pulsed neutron sources. Report of a workshop held at Argonne National Laboratory October 21--24, 1975

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, J.M.; Werner, S.A. (eds.)

    1975-01-01

    The report contains the conclusions that were drawn by nine panels of scientists in the fields of Biology; Chemical Spectroscopy; Chemical Structures of Crystalline Solids; Chemical Structures of Disordered Solids and Inhomogeneous Systems; Dynamics of Solids, Liquids, Glasses and Gases; Magnetism; Neutron Sources; and Radiation Effects. The nine panel reports describe the applications found in these scientific areas, accompanying them with conceptual instruments designed for the measurements and with calculations to establish feasibility.

  3. Conceptual design study and evaluation of an advanced treatment process applying a submerged combustion technique for spent solvents

    International Nuclear Information System (INIS)

    An advanced treatment process based on a submerged combustion technique was proposed for spent solvents and the distillation residues containing transuranium (TRU) nuclides. A conceptual design study and the preliminary cost estimation of the treatment facility applying the process were conducted. Based on the results of the study, the process evaluation on the technical features, such as safety, volume reduction of TRU waste and economics was carried out. The key requirements for practical use were also summarized. It was shown that the process had the features as follows: the simplified treatment and solidification steps will not generate secondary aqueous wastes, the volume of TRU solid waste will be reduced less than one tenth of that of a reference technique (pyrolysis process), and the facility construction cost is less than 1 % of the total construction cost of a future large scale reprocessing plant. As for the low level wastes of calcium phosphate, it was shown that the further removal of β · γ nuclides with TRU nuclides from the wastes would be required for the safety in interim storage and transportation and for the load of shielding. (author)

  4. Archaeal Diversity in Biofilm Technologies Applied to Treat Urban and Industrial Wastewater: Recent Advances and Future Prospects

    Directory of Open Access Journals (Sweden)

    Jesús González-López

    2013-09-01

    Full Text Available Biological wastewater treatment (WWT frequently relies on biofilms for the removal of anthropogenic contaminants. The use of inert carrier materials to support biofilm development is often required, although under certain operating conditions microorganisms yield structures called granules, dense aggregates of self-immobilized cells with the characteristics of biofilms maintained in suspension. Molecular techniques have been successfully applied in recent years to identify the prokaryotic communities inhabiting biofilms in WWT plants. Although methanogenic Archaea are widely acknowledged as key players for the degradation of organic matter in anaerobic bioreactors, other biotechnological functions fulfilled by Archaea are less explored, and research on their significance and potential for WWT is largely needed. In addition, the occurrence of biofilms in WWT plants can sometimes be a source of operational problems. This is the case for membrane bioreactors (MBR, an advanced technology that combines conventional biological treatment with membrane filtration, which is strongly limited by biofouling, defined as the undesirable accumulation of microbial biofilms and other materials on membrane surfaces. The prevalence and spatial distribution of archaeal communities in biofilm-based WWT as well as their role in biofouling are reviewed here, in order to illustrate the significance of this prokaryotic cellular lineage in engineered environments devoted to WWT.

  5. Proposal of requirements for performance in Brazil for systems of external individual monitoring for neutrons applying the TLD-albedo technique; Proposta de requisitos de desempenho no Brasil para sistemas de monitoracao individual externa para neutrons empregando a tecnica TLD-albedo

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Marcelo M.; Mauricio, Claudia L.P.; Pereira, Walsan W.; Fonseca, Evaldo S. da, E-mail: marcelo@ird.gov.b, E-mail: claudia@ird.gov.b, E-mail: walsan@ird.gov.b, E-mail: evaldo@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Silva, Ademir X., E-mail: ademir@con.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil).

    2009-07-01

    This work presents a criteria and conditions proposal for the regulations in Brazil of individual monitoring systems for neutrons applying the albedo technique with thermoluminescent detectors. Tests are proposed for the characterization performance of the system based on the Regulation ISO 21909 and on the experience of the authors

  6. Neutron powder diffraction

    International Nuclear Information System (INIS)

    Neutron powder diffraction is a powerful technique that provides a detailed description of moderately complex crystal structures. This is nowhere more apparent than in the area of high temperature superconductors where neutron powder diffraction has provided precise structural and magnetic information, not only under ambient conditions but also at high and low temperatures and high pressures. Outside superconductor research, the variety of materials studied by neutron powder diffraction is equally impressive including zeolites, fast ionic conductors, permanent magnets and materials undergoing phase transitions. Recent advances that include high resolution studies and real-time crystallography are presented. Future possibilities of neutron powder diffraction are discussed

  7. Support for cold neutron utilization

    International Nuclear Information System (INIS)

    - Support for experiments by users of cold neutron scattering instrument - Short-term training of current and potential users of cold neutron scattering instrument for their effective use of the instrument - International collaboration for advanced utilization of cold neutron scattering instruments - Selection and training of qualified instrument scientists for vigorous research endeavors and outstanding achievements in experiments with cold neutron - Research on nano/bio materials using cold neutron scattering instruments - Bulk nano structure measurement using small angle neutron scattering and development of analysis technique

  8. Personnel neutron dose assessment upgrade: Volume 2, Field neutron spectrometer for health physics applications

    International Nuclear Information System (INIS)

    Both the (ICRP) and the (NCPR) have recommended an increase in neutron quality factors and the adoption of effective dose equivalent methods. The series of reports entitled Personnel Neutron Dose Assessment Upgrade (PNL-6620) addresses these changes. Volume 1 in this series of reports (Personnel Neutron Dosimetry Assessment) provided guidance on the characteristics, use, and calibration of personnel neutron dosimeters in order to meet the new recommendations. This report, Volume 2: Field Neutron Spectrometer for Health Physics Applications describes the development of a portable field spectrometer which can be set up for use in a few minutes by a single person. The field spectrometer described herein represents a significant advance in improving the accuracy of neutron dose assessment. It permits an immediate analysis of the energy spectral distribution associated with the radiation from which neutron quality factor can be determined. It is now possible to depart from the use of maximum Q by determining and realistically applying a lower Q based on spectral data. The field spectrometer is made up of two modules: a detector module with built-in electronics and an analysis module with a IBM PC/reg sign/-compatible computer to control the data acquisition and analysis of data in the field. The unit is simple enough to allow the operator to perform spectral measurements with minimal training. The instrument is intended for use in steady-state radiation fields with neutrons energies covering the fission spectrum range. The prototype field spectrometer has been field tested in plutonium processing facilities, and has been proven to operate satisfactorily. The prototype field spectrometer uses a 3He proportional counter to measure the neutron energy spectrum between 50 keV and 5 MeV and a tissue equivalent proportional counter (TEPC) to measure absorbed neutron dose

  9. Opportunities for in-situ diffraction studies of advanced materials under extreme conditions at the US spallation neutron source

    Indian Academy of Sciences (India)

    J P Hodges

    2008-11-01

    The spallation neutron source (SNS) is an accelerator-based neutron source in Oak Ridge, Tennessee. Currently ramping up to 1.4 MW operating power, SNS will provide the most intense pulsed neutron beams in the world for scientific research and industrial development. Built by a partnership of six DOE laboratories SNS is operated as a user facility, open to scientists and engineers from universities, industry, and government laboratories in the United States and abroad. Eighteen dedicated beamline instruments are currently funded; four are completed and in operation, five are to be commissioned within a year and the others are at various stages of design and construction. All instruments at SNS have been designed to best in class and will provide unprecedented opportunities to explore the structure and dynamics of all materials. Amongst the funded instruments are a high-resolution very fast powder diffractometer (POWGEN3) optimized for parametric studies of materials under a wide range of conditions (, , and flowing gases), an ultrahigh-pressure diffractometer (SNAP) for materials under extreme conditions of pressure (up to 100 GPa) and temperature, an engineering materials diffractometer (VULCAN) for mapping strain, texture and fundamental aspects of materials behaviour of high performance materials under strain forces, a high flux disordered materials diffractometer (NOMAD) for liquids, glasses and disorder in crystalline materials, and a small angle scattering diffractometer (EQSANS) for investigating precipitates, crystallization, domains and nanoparticles in composite materials. ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.

  10. Neutron imaging in materials science

    OpenAIRE

    Nikolay Kardjilov; Ingo Manke; André Hilger; Markus Strobl; John Banhart

    2011-01-01

    Neutron imaging is a non-destructive technique that can reveal the interior of many materials and engineering components and also probe magnetic fields. Within the past few years, several new imaging modes have been introduced that extend the scope of neutron imaging beyond conventional neutron attenuation imaging, yielding both 2- and 3D information about properties and phenomena inaccessible until now. We present an overview of the most important advances in the application of neutron imagi...

  11. Neutron sources and applications

    Energy Technology Data Exchange (ETDEWEB)

    Price, D.L. [ed.] [Argonne National Lab., IL (United States); Rush, J.J. [ed.] [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

    1994-01-01

    Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications.

  12. Neutron sources and applications

    International Nuclear Information System (INIS)

    Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications

  13. Neutron stimulated emission computed tomography applied to the assessment of calcium deposition due to the presence of microcalcifications associated with breast cancer; Tomografia computadorizada de emissao estimulada por neutrons aplicada para avaliar a deposicao de calcio devido a presenca de microcalcificacoes associadas ao cancer de mama

    Energy Technology Data Exchange (ETDEWEB)

    Viana, Rodrigo S.S.; Yoriyaz, Helio [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, (SP) (Brazil)

    2011-07-01

    In this paper we presented an application of the Neutron Stimulated Emission Computed Tomography (NSECT), which uses a thin beam of fast neutrons to stimulate stable nuclei in a sample, emitting characteristic gamma radiation. The photon energy is unique and it is used to identify the emitting nuclei. This technique was applied for evaluating the calcium isotopic composition changing due to the development of breast microcalcifications. A particular situation was simulated in which clustered microcalcifications were modeled with diameters less than 1.40 mm. In this case, neutron beam breast spectroscopy was successful in detecting the counting changes in the photon emission spectra for energies, which are characteristics of 4{sup 0C}a isotope in a low deposited dose rate. (author)

  14. Neutron spectrometry and dosimetry by means of Bonner spheres system and artificial neural networks applying robust design of artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Martinez B, M.R.; Ortiz R, J.M.; Vega C, H.R. [UAZ, Av. Ramon Lopez Velarde No. 801, 98000 Zacatecas (Mexico)

    2006-07-01

    An Artificial Neural Network has been designed, trained and tested to unfold neutron spectra and simultaneously to calculate equivalent doses. A set of 187 neutron spectra compiled by the International Atomic Energy Agency and 13 equivalent doses were used in the artificial neural network designed, trained and tested. In order to design the neural network was used the robust design of artificial neural networks methodology, which assures that the quality of the neural networks takes into account from the design stage. Unless previous works, here, for first time a group of neural networks were designed and trained to unfold 187 neutron spectra and at the same time to calculate 13 equivalent doses, starting from the count rates coming from the Bonner spheres system by using a systematic and experimental strategy. (Author)

  15. Near Real-Time Nondestructive Active Inspection Technologies Utilizing Delayed γ-Rays and Neutrons for Advanced Safeguards

    International Nuclear Information System (INIS)

    In this two year project, the research team investigated how delayed γ-rays from short-lived fission fragments detected in the short interval between irradiating pulses can be exploited for advanced safeguards technologies. This program contained experimental and modeling efforts. The experimental effort measured the emitted spectra, time histories and correlations of the delayed γ-rays from aqueous solutions and solid targets containing fissionable isotopes. The modeling effort first developed and benchmarked a hybrid Monte Carlo simulation technique based on these experiments. The benchmarked simulations were then extended to other safeguards scenarios, allowing comparisons to other advanced safeguards technologies and to investigate combined techniques. Ultimately, the experiments demonstrated the possible utility of actively induced delayed γ-ray spectroscopy for fissionable material assay.

  16. Near Real-Time Nondestructive Active Inspection Technologies Utilizing Delayed γ-Rays and Neutrons for Advanced Safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, Alan [Idaho State Univ., Pocatello, ID (United States). Idaho Accelerator Center, Dept. of Physics; Reedy, E. T.E. [Idaho State Univ., Pocatello, ID (United States). Dept. of Phyics, Idaho Accelerator Center; Mozin, V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tobin, S. J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Nuclear Nonproliferation

    2015-02-12

    In this two year project, the research team investigated how delayed γ-rays from short-lived fission fragments detected in the short interval between irradiating pulses can be exploited for advanced safeguards technologies. This program contained experimental and modeling efforts. The experimental effort measured the emitted spectra, time histories and correlations of the delayed γ-rays from aqueous solutions and solid targets containing fissionable isotopes. The modeling effort first developed and benchmarked a hybrid Monte Carlo simulation technique based on these experiments. The benchmarked simulations were then extended to other safeguards scenarios, allowing comparisons to other advanced safeguards technologies and to investigate combined techniques. Ultimately, the experiments demonstrated the possible utility of actively induced delayed γ-ray spectroscopy for fissionable material assay.

  17. Neutron Time of Flight Spectrometer for Velocity Selector Calibration

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Small angle neutron spectrometer on China Advanced Research Reactor (CARR) is located at neutron guide hall and is installed on the end of cold neutron guide. Velocity selector which can purify white light neutron beam into monochromatic neutron beam with wavelength

  18. Solution of the neutron diffusion equation to study the 3D distribution of power, applied to nuclear reactors; Solucao da equacao de difusao de neutrons para o estudo da distribuicao de potencia em 3D, aplicado a reatores nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Danilo Leite

    2013-07-01

    This work aims to present a study about the power distribution behavior in a PWR type reactor, considering both intensity and migration of power peaks due to insertion of control rods into the core. Employing the multidimensional steady-state neutron diffusion equation in order to simulate the neutron flux, and using the Finite Difference Method. Furthermore, based on the axial power distribution on the largest heat flux rod, is carried out thermal analysis of this rod and associated coolant channel. For this purpose is employed the FueLRod{sub 3}D code, it uses the Finite Element Method to model the fuel rod and the associated coolant channel, allowing the thermohydraulics simulation of a single rod discretized in three dimensions, considering the heat flux from the pellet, crossing the gap and the cladding until it reaches the coolant. (author)

  19. Compact variable-energy neutron generators for fast neutron applications

    International Nuclear Information System (INIS)

    Full text: The advent of compact low-energy accelerators capable of delivering intense beams of charged particles has opened up the opportunity of generating fast neutron beams of sufficient intensity for many previously inaccessible applications. A continuing drawback in the intensity or quality of the neutron beam stems from the nature of the beam-target interaction. To generate mono-energetic neutrons the ideal reaction is the d(d,n)3He reaction. For a sufficiently dense target material the deuterium should be a liquid or solid, but this is invariably impractical due to the associated complex cryogenic requirements. The only alternative is a gas target maintained at high pressure. The disadvantage of a gas target is the question of how to contain a high pressure gas cell and introduce an energetic ion beam with minimal incident beam energy degradation. The concept of an advanced differential pumping system has already been demonstrated, with spinning discs to isolate the gas cell during non-delivery of beam from a pulsed accelerator. Such a process is however, ineffective for higher duty cycles. To overcome this, a novel system has been developed utilizing a plasma porthole in conjunction with a differential pumping system. Such a system has been demonstrated to be highly effective in terms of installing a compact fast neutron generator for applications in the materials research industry. During recent years considerable effort has been directed towards the use of fast neutron generators for contraband and explosives detection. The methodology can also be directed to other applications, more specifically in minerals prospecting and materials characterization. Here we discuss two specific applications that can have a direct impact on the South African economy: 1) Assaying of gold ore in rock: The 279 keV gamma-ray emitted during the decay of 197mAu can be readily observed through the irradiation of natural gold using neutrons of energy 1-6 MeV with optimum

  20. Neutron resonance averaging

    International Nuclear Information System (INIS)

    The principles of resonance averaging as applied to neutron capture reactions are described. Several illustrations of resonance averaging to problems of nuclear structure and the distribution of radiative strength in nuclei are provided. 30 refs., 12 figs

  1. Neutrons against cancer

    Science.gov (United States)

    Dovbnya, A. N.; Kuplennikov, E. L.; Kandybey, S. S.; Krasiljnikov, V. V.

    2014-09-01

    The review is devoted to the analysis and generalization of the research carried out during recent years in industrially advanced countries on the use of fast, epithermal, and thermal neutrons for therapy of malignant tumors. Basic facilities for neutron production used for cancer treatment are presented. Optimal parameters of therapeutic beams are described. Techniques using neutrons of different energy regions are discussed. Results and medical treatment efficiency are given. Comparison of the current state of neutron therapy of tumors and alternative treatments with beams of protons and carbon ions has been conducted. Main attention is given to the possibility of the practical use of accumulated experience of application of neutron beams for cancer therapy.

  2. Study of fluid fuel influence on delayed neutron in Molten Salt Reactor

    International Nuclear Information System (INIS)

    Background: The Molten Salt Reactor (MSR) is one of the six advanced reactor types for future nuclear energy systems in the Generation IV International Forum (GIF), possessing the advantages of good neutron economics, inherent safety, processing online, nuclear nonproliferation, etc. Due to the fluid fuel, a part of delayed neutron precursors drifts out of the reactor and decays in the loop, which is different from the solid-fuel reactor. Purpose: The distribution of delayed neutrons with different fuel velocity for Molten Salt Reactor Experiment (MSRE) is analyzed to provide reference for safety design of MSR. Methods: Based on the neutron kinetics and approximate method of homogeneous reactor, a distribution model of delayed neutron was presented. This model is applied to the distribution study of delayed neutrons with different fuel velocity. Results: The number of delayed neutrons in a core radius of 20 cm was more than that in a core radius of 30 cm. When the flow velocity of fuel decreased by a half, the discrepancy of delayed neutrons between the fifth-group and sixth-group precursors is within 6%. Conclusion: The number of delayed neutrons is increasing toward the center of reactor core. The group of delayed neutron precursors with shorter half-time has little effect on the flow velocity of molten salt. (authors)

  3. Neutron sources for the medical use

    International Nuclear Information System (INIS)

    Recently encouraging results of the neutron radiation therapy have been obtained in clinical trials. In addition to the therapy, the neutrons are applied to the diagnosis besides the production of radioisotopes, that is, in-vivo activation analysis and neutron radiograph. In the medicine, high energy neutrons are effectively used. The necessary conditions, especially neutron source reactions, angular distributions, etc., and the neutron dosimetry including neutron kerma factors are discussed. Finally the requirements for neutron sources, their related problems and nuclear data are enumerated. (author)

  4. Shape coexistence in the "island of inversion": Search for the $0^{+}_{2}$ state in $^{32}$Mg applying a two-neutron transfer reaction

    CERN Multimedia

    Blazhev, A A; Nardelli, S; Kruecken, R; Voulot, D; Hadinia, B; Kalkuehler, M; Clement, E; Habs, D; Diriken, J V J; Wady, P T; Angus, L J

    2008-01-01

    We aim to study the structure of neutron-rich nuclei in the "island of inversion" where intruder $\\textit{fp}$-orbitals favouring deformed states compete with the normal spherical $\\textit{sd}$-orbitals. In particular, we search for the spherical 0$^{+}_{2}$ state in $^{32}$Mg which should coexist with the deformed ground state but has not been observed so far. We propose to populate this state by a (t,p) two-neutron transfer reaction with a $^{30}$Mg beam at around 2 MeV/u from REX-ISOLDE impinging on a tritium-loaded Ti target. The $\\gamma$-rays are detected by MINIBALL and the particles by our new set-up of segmented Si detectors. The results will shed new light on the breaking of the shell closure at $\\textit{N}$ = 20 in this region.

  5. Quantitative phase analysis by neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Hee; Song, Su Ho; Lee, Jin Ho; Shim, Hae Seop [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-06-01

    This study is to apply quantitative phase analysis (QPA) by neutron diffraction to the round robin samples provided by the International Union of Crystallography(IUCr). We measured neutron diffraction patterns for mixed samples which have several different weight percentages and their unique characteristic features. Neutron diffraction method has been known to be superior to its complementary methods such as X-ray or Synchrotron, but it is still accepted as highly reliable under limited conditions or samples. Neutron diffraction has strong capability especially on oxides due to its scattering cross-section of the oxygen and it can become a more strong tool for analysis on the industrial materials with this quantitative phase analysis techniques. By doing this study, we hope not only to do one of instrument performance tests on our HRPD but also to improve our ability on the analysis of neutron diffraction data by comparing our QPA results with others from any advanced reactor facilities. 14 refs., 4 figs., 6 tabs. (Author)

  6. Epithermal neutron activation, radiometric, correlation and principal component analysis applied to the distribution of major and trace elements in some igneous and metamorphic rocks from Romania

    Energy Technology Data Exchange (ETDEWEB)

    Cristache, C.I. [National Institute of Research and Development for Physics and Nuclear Engineering Horia-Hulubei, P.O. Box MG-6, 077125 Magurele, Ilfov (Romania); Duliu, O.G. [University of Bucharest, Department of Atomic and Nuclear Physics, P.O. Box MG-11, 077125 Magurele, Ilfov (Romania)], E-mail: duliu@b.astral.ro; Culicov, O.A.; Frontasyeva, M.V. [Joint Institute of Nuclear Research, 6, Joliot Curie str. 141980, Dubna (Russian Federation); Ricman, C. [Geological Institute of Romania, 1 Caransebes Street, 012271 Bucharest (Romania); Toma, M. [National Institute of Research and Development for Physics and Nuclear Engineering Horia-Hulubei, P.O. Box MG-6, 077125 Magurele, Ilfov (Romania)

    2009-05-15

    Six major (Na, Al, K, Ca, Ti, Fe) and 28 trace (Sc, Cr, V, Mn, Co, Zn, Cu, As, Br, Sr, Rb, Zr, Mo, Sn, Sb, Ba, Cs, La, Ce, Nd, Eu, Sm, Tb, Hf, Ta, W, Th and U) elements were determined by epithermal neutron activation analysis (ENAA) in nine Meridional Carpathian and Macin Mountains samples of igneous and metamorphic rocks. Correlation and principal factor analysis were used to interpret data while natural radionuclides radiometry shows a good correlation with ENAA results.

  7. Neutron diagnostic investigations with a research reactor

    International Nuclear Information System (INIS)

    Some aspects of the use of neutron transmission analysis in applied research, as pursued at McMaster University (Canada), are examined. Examples considered are void measurements in two-phase flow, neutron conversion enhancement in neutron radiography, reconstruction of interior bulk heterogenities in solids and temperature sensing with neutrons. (author)

  8. Potentialities and practical limitations of absolute neutron dosimetry using thin films of uranium and thorium applied to the fission track dating

    CERN Document Server

    Bigazzi, G; Hadler-Neto, J C; Iunes, P J; Paulo, S R; Oddone, M; Osorio, A M A; Zúñiga, A G

    1999-01-01

    Neutron dosimetry using natural uranium and thorium thin films makes possible that mineral dating by the fission-track method can be accomplished, even when poor thermalized neutron facilities are employed. In this case, the contributions of the fissions of sup 2 sup 3 sup 5 U, sup 2 sup 3 sup 8 U and sup 2 sup 3 sup 2 Th induced by thermal, epithermal and fast neutrons to the population of tracks produced during irradiation are quantified through the combined use of natural uranium and thorium films. If the Th/U ratio of the sample is known, only one irradiation (where the sample and the films of uranium and thorium are present) is necessary to perform the dating. However, if that ratio is unknown, it can be determined through another irradiation where the mineral to be dated and both films are placed inside a cadmium box. Problems related with film manufacturing and calibration are discussed. Special attention is given to the utilization of thin films having very low uranium content. The problems faced sugg...

  9. Postirradiation evaluations of capsules HANS-1 and HANS-2 irradiated in the HFIR target region in support of fuel development for the advanced neutron source

    International Nuclear Information System (INIS)

    This report describes the design, fabrication, irradiation, and evaluation of two capsule tests containing U3Si2 fuel particles in contact with aluminum. The tests were in support of fuel qualification for the Advanced Neutron Source (ANS) reactor, a high-powered research reactor that was planned for the Oak Ridge National Laboratory. At the time of these tests, the fuel consisted of U3Si2, containing highly enriched uranium dispersed in aluminum at a volume fraction of ∼0.15. The extremely high thermal flux in the target region of the High Flux Isotope Reactor provided up to 90% burnup in one 23-d cycle. Temperatures up to 450 degrees C were maintained by gamma heating. Passive SiC temperature monitors were employed. The very small specimen size allowed only microstructural examination of the fuel particles but also allowed many specimens to be tested at a range of temperatures. The determination of fission gas bubble morphology by microstructural examination has been beneficial in developing a fuel performance model that allows prediction of fuel performance under these extreme conditions. The results indicate that performance of the reference fuel would be satisfactory under the ANS conditions. In addition to U3Si2, particles of U3Si, UAl2, UAlx, and U3O8 were tested

  10. Modeling and analysis framework for core damage propagation during flow-blockage-initiated accidents in the Advanced Neutron Source Reactor at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.H.; Taleyarkhan, R.P.; Navarro-Valenti, S.; Georgevich, V.

    1995-09-01

    This paper describes modeling and analysis to evaluate the extent of core damage during flow blockage events in the Advanced Neutron Source (ANS) reactor planned to be built at the Oak Ridge National Laboratory (ORNL). Damage propagation is postulated to occur from thermal conduction between damaged and undamaged plates due to direct thermal contact. Such direct thermal contact may occur because of fuel plate swelling during fission product vapor release or plate buckling. Complex phenomena of damage propagation were modeled using a one-dimensional heat transfer model. A scoping study was conducted to learn what parameters are important for core damage propagation, and to obtain initial estimates of core melt mass for addressing recriticality and steam explosion events. The study included investigating the effects of the plate contact area, the convective heat transfer coefficient, thermal conductivity upon fuel swelling, and the initial temperature of the plate being contacted by the damaged plate. Also, the side support plates were modeled to account for their effects on damage propagation. The results provide useful insights into how various uncertain parameters affect damage propagation.

  11. Neutron analysis of spent fuel storage installation using parallel computing and advance discrete ordinates and Monte Carlo techniques.

    Science.gov (United States)

    Shedlock, Daniel; Haghighat, Alireza

    2005-01-01

    In the United States, the Nuclear Waste Policy Act of 1982 mandated centralised storage of spent nuclear fuel by 1988. However, the Yucca Mountain project is currently scheduled to start accepting spent nuclear fuel in 2010. Since many nuclear power plants were only designed for -10 y of spent fuel pool storage, > 35 plants have been forced into alternate means of spent fuel storage. In order to continue operation and make room in spent fuel pools, nuclear generators are turning towards independent spent fuel storage installations (ISFSIs). Typical vertical concrete ISFSIs are -6.1 m high and 3.3 m in diameter. The inherently large system, and the presence of thick concrete shields result in difficulties for both Monte Carlo (MC) and discrete ordinates (SN) calculations. MC calculations require significant variance reduction and multiple runs to obtain a detailed dose distribution. SN models need a large number of spatial meshes to accurately model the geometry and high quadrature orders to reduce ray effects, therefore, requiring significant amounts of computer memory and time. The use of various differencing schemes is needed to account for radial heterogeneity in material cross sections and densities. Two P3, S12, discrete ordinate, PENTRAN (parallel environment neutral-particle TRANsport) models were analysed and different MC models compared. A multigroup MCNP model was developed for direct comparison to the SN models. The biased A3MCNP (automated adjoint accelerated MCNP) and unbiased (MCNP) continuous energy MC models were developed to assess the adequacy of the CASK multigroup (22 neutron, 18 gamma) cross sections. The PENTRAN SN results are in close agreement (5%) with the multigroup MC results; however, they differ by -20-30% from the continuous-energy MC predictions. This large difference can be attributed to the expected difference between multigroup and continuous energy cross sections, and the fact that the CASK library is based on the old ENDF

  12. Determination of the acute toxicities of physicochemical pretreatment and advanced oxidation processes applied to dairy effluents on activated sludge.

    Science.gov (United States)

    Sivrioğlu, Özge; Yonar, Taner

    2015-04-01

    In this study, the acute toxicities of raw, physicochemical pre-treated, ozonated, and Fenton reagent applied samples of dairy wastewater toward activated sludge microorganisms, evaluated using the International Organization for Standardization's respiration inhibition test (ISO 8192), are presented. Five-day biological oxygen demand (BOD5) was measured to determine the biodegradability of physicochemical treatment, ozonation, Fenton oxidation or no treatment (raw samples) of dairy wastewater. Chemical pretreatment positively affected biodegradability, and the inhibition exhibited by activated sludge was removed to a considerable degree. Ozonation and the Fenton process exhibited good chemical oxygen demand removal (61%) and removal of toxins. Low sludge production was observed for the Fenton process applied to dairy effluents. We did not determine the inhibitory effect of the Fenton-process on the activated sludge mixture. The pollutant-removal efficiencies of the applied processes and their associated operating costs were determined.

  13. Development of neutron diffraction measurement of residual stresses

    International Nuclear Information System (INIS)

    Neutron diffraction technic for the measurement of residual stresses in engineering materials and components are developed by using the high resolution powder diffractometer (HRPD) and position sensitive detection (PSD) unit at HANARO. During the development, practical measurement procedures under the field conditions has been established and some special tools devised, too. We described in this report the brief principle of neutron diffraction measurement for stresses in the components, detailed measuring procedures and experimental set-ups with various alignment methods and ideas of the instrument configuration therein by applying it to VAMAS round robin samples set prepared by advance institutes worldwide. (author). 15 tabs., 5 figs

  14. Cross-Cultural Dimensions of Applied, Critical, and Transformational Leadership: Women Principals Advancing Social Justice and Educational Equity

    Science.gov (United States)

    Santamaría, Lorri J.; Jean-Marie, Gaëtane

    2014-01-01

    This study, based on the qualitatively rendered experiences and perceptions of educational leaders from historically underserved backgrounds in the US, argues that identity impacts leadership practice. To make this point, researchers build upon an emergent theoretical framework for applied critical leadership from the theories and traditions of…

  15. Neutron Radiography

    OpenAIRE

    Reddy, A. R.; Rao, M. V. N.

    2012-01-01

    The field of neutron radiography with special reference to isotopic neutron radiography has been reviewed. Different components viz., sources, collimators, imaging systems are described. Various designs of neutron radiography facilities, their relative merits and demerits , the appropriateness of each design depending on the object to be radiographed, and economics of each technique are also dealt. The applications of neutron radiography are also briefly presented.

  16. Epithermal neutron activation, radiometric, correlation and principal component analysis applied to the distribution of major and trace elements in some igneous and metamorphic rocks from Romania.

    Science.gov (United States)

    Cristache, C I; Duliu, O G; Culicov, O A; Frontasyeva, M V; Ricman, C; Toma, M

    2009-05-01

    Six major (Na, Al, K, Ca, Ti, Fe) and 28 trace (Sc, Cr, V, Mn, Co, Zn, Cu, As, Br, Sr, Rb, Zr, Mo, Sn, Sb, Ba, Cs, La, Ce, Nd, Eu, Sm, Tb, Hf, Ta, W, Th and U) elements were determined by epithermal neutron activation analysis (ENAA) in nine Meridional Carpathian and Macin Mountains samples of igneous and metamorphic rocks. Correlation and principal factor analysis were used to interpret data while natural radionuclides radiometry shows a good correlation with ENAA results. PMID:19231213

  17. Inertial electro-magnetostatic plasma neutron sources

    International Nuclear Information System (INIS)

    Two types of systems are being studied experimentally as D-T plasma neutron sources. In both concepts, spherical convergence of either electrons or ions or both is used to produce a dense central focus within which D-T fusion reactions produce 14 MeV neutrons. One concept uses nonneutral plasma confinement principles in a Penning type trap. In this approach, combined electrostatic and magnetic fields provide a vacuum potential well within which electrons are confined and focused. A small (6 mm radius) spherical machine has demonstrated a focus of 30 microm radius, with a central density of up to 35 times the Brillouin density limit of a static trap. The resulting electron plasma of up to several 1013 cm-3 provides a multi-kV electrostatic well for confining thermonuclear ions as a neutron source. The second concept (Inertial Electrostatic Confinement, or IEC) uses a high-transparence grid to form a global well for acceleration and confinement of ions. Such a system has demonstrated steady neutron output of 2 x 1010 s-1. The present experiment will scale this to >1011 s-1. Advanced designs based on each concept have been developed recently. In these proposed approaches, a uniform-density electron sphere forms an electrostatic well for ions. Ions so trapped may be focused by spherical convergence to produce a dense core. An alternative approach produces large amplitude spherical oscillations of a confined ion cloud by a small, resonant modulation of the background electrons. In both the advanced Penning trap approach and the advanced IEC approach, the electrons are magnetically insulated from a large (up to 100 kV) applied electrostatic field. The physics of these devices is discussed, experimental design details are given, present observations are analyzed theoretically, and the performance of future advanced systems are predicted

  18. Fission neutron statistical emission

    International Nuclear Information System (INIS)

    The statistical model approach FINESSE (FIssion NEutronS' Statistical Emission) for the description of fission neutron multiplicities, energy spectra and angular distributions is described. Based on an extended Weisskopf ansatz and on a realistic temperature distribution it provides a fragment mass number dependent description of fission neutron data. Model parameters (optical potential, n/γ competition) were fixed on the basis of the 252Cf(sf) (nuclear data standard). Combined with a phenomenological fission model for predicting relevant fragment data as function of asymmetry. FINESSE can be applied to any fission reaction of actinides in the Th-Cf region without further parameter adjustment. Results are presented for 252Cf(sf) and neutron induced fission of 235U, 239Pu, 232Th. Effects of multiple-chance fission are discussed for 232Th(n,xnf) reacation. (author). 46 refs, 11 figs

  19. Applying the High-Temperature TL in LiF:Mg,Ti to Mixed Thermal Neutron-Gamma Dosimetry - a Review

    International Nuclear Information System (INIS)

    In a recent review article on the subject of High Temperature TL (HTTL) characteristics, criticized the attempts to use the two peak method in mixed field neutron-gamma ray dosimetry, promoting their firm conviction, as also published in an earlier survey by that this issue is unworthy to be investigated. Although it should have been a review, the article concentrates in the corresponding section only on one of our publications on the subject , trying to prove their view through our highly problematic results, as they define it. The ''problematics'' will be dealt with in specific future publications, but in order to present a realistic and balanced range of views on this issue, a comprehensive review of the results published on this topic is to be given. Many works deal with mixed field dosimetric application of the two-peak method, but for the sake of clarity we will concentrate only on the applications of 6LiF for thermal neutron fields, as presented in our publications(

  20. Advanced Representation Technologies Applied to the Temple of Neptune, the Sphinx and the Metope in the Archaeological Park of Paestum

    Science.gov (United States)

    Cardinale, T.; Valva, R.; Lucarelli, M.

    2013-02-01

    The Summer School of Surveying and 3D modelling in Paestum was an opportunity to explore the use of innovative tools and advanced techniques in the design, implementation and management of surveys of historic and artistic complexes. In general such methods are used specifically for the development and management of vulnerability maps of existing heritage and so for the preventive conservation and valorisation of the built environment. The accurate detection of risk situations and the systematic promotion of highly selected and minimally invasive maintenance practices means that restoration and the efficiency of cycles of intervention can be optimized, with clear benefits from economic and cultural points of view. The group worked on the survey and 3D modelling of the Temple of Neptune, the Sphinx and the Metope of the Archaeological Park in Paestum.

  1. Single- and two-phase flow modeling for coupled neutronics / thermal-hydraulics transient analysis of advanced sodium-cooled fast reactors

    International Nuclear Information System (INIS)

    liquid film after dryout onset. The validation of the extended TRACE code has been achieved through the successful simulation of out-of-pile experiments. A review of available sodium boiling test data has first been carried out, and complementary tests have been selected to assess the quality of the different physical models like the pressure drop and cooling limits under quasi steady-state conditions, as well as the simulation of a loss-of-flow transient. The extended TRACE code has demonstrated its capacity to predict the main thermal-hydraulics characteristics such as the single- and two-phase pressure drop and heat transfer, as also the boiling inception, void fraction evolution and expansion of the boiling region, pressure evolution, as well as coolant and clad temperatures. The natural convection test conducted in 2009 in the Phenix reactor has been used to validate TRACE single-phase sodium flow modelling. Data from the Phenix test have been used for the validation of the FAST code system. Analyses based on a point-kinetics TRACE model and on coupled TRACE/PARCS 3D-kinetics modelling have enabled an in-depth understanding of the transient behaviour of a sodium-cooled fast reactor core, leading to potential improvements in the FAST code system. The experimental power evolution could be satisfactorily reproduced within the measurement uncertainties with both models, and the detailed analysis of the core neutronics has enabled one to define the most important reactivity feedbacks taking place during the considered transient. The developed tool has been applied to the simulation of a hypothetical, unprotected loss-of-flow event for one of the European SFR core concepts. This study has demonstrated the new calculation tool’s capability to adequately simulate the core response through the modelling of single- and two-phase sodium flow, coupled to 3D neutron kinetics. Thereby, the space-dependent reactivity feedbacks, such as the void and Doppler effects, have been

  2. General Design for CARR Neutron Guide System

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    A neutron guide system has been designed and partly installed at the China Advanced Research Reactor (CARR) to transport cold neutrons from the cold neutron source (CNS) to several instruments,which are situated in a separate guide hall of 30 m×60 m.

  3. Neutron Skins and Neutron Stars

    OpenAIRE

    Piekarewicz, J

    2013-01-01

    The neutron-skin thickness of heavy nuclei provides a fundamental link to the equation of state of neutron-rich matter, and hence to the properties of neutron stars. The Lead Radius Experiment ("PREX") at Jefferson Laboratory has recently provided the first model-independence evidence on the existence of a neutron-rich skin in 208Pb. In this contribution we examine how the increased accuracy in the determination of neutron skins expected from the commissioning of intense polarized electron be...

  4. Statistically based uncertainty analysis for ranking of component importance in the thermal-hydraulic safety analysis of the Advanced Neutron Source Reactor

    International Nuclear Information System (INIS)

    The Analytic Hierarchy Process (AHP) has been used to help determine the importance of components and phenomena in thermal-hydraulic safety analyses of nuclear reactors. The AHP results are based, in part on expert opinion. Therefore, it is prudent to evaluate the uncertainty of the AHP ranks of importance. Prior applications have addressed uncertainty with experimental data comparisons and bounding sensitivity calculations. These methods work well when a sufficient experimental data base exists to justify the comparisons. However, in the case of limited or no experimental data the size of the uncertainty is normally made conservatively large. Accordingly, the author has taken another approach, that of performing a statistically based uncertainty analysis. The new work is based on prior evaluations of the importance of components and phenomena in the thermal-hydraulic safety analysis of the Advanced Neutron Source Reactor (ANSR), a new facility now in the design phase. The uncertainty during large break loss of coolant, and decay heat removal scenarios is estimated by assigning a probability distribution function (pdf) to the potential error in the initial expert estimates of pair-wise importance between the components. Using a Monte Carlo sampling technique, the error pdfs are propagated through the AHP software solutions to determine a pdf of uncertainty in the system wide importance of each component. To enhance the generality of the results, study of one other problem having different number of elements is reported, as are the effects of a larger assumed pdf error in the expert ranks. Validation of the Monte Carlo sample size and repeatability are also documented

  5. Natural Language Processing and Machine Learning (NLP/ML): Applying Advances in Biomedicine to the Earth Sciences

    Science.gov (United States)

    Duerr, R.; Myers, S.; Palmer, M.; Jenkins, C. J.; Thessen, A.; Martin, J.

    2015-12-01

    Semantics underlie many of the tools and services available from and on the web. From improving search results to enabling data mashups and other forms of interoperability, semantic technologies have proven themselves. But creating semantic resources, especially re-usable semantic resources, is extremely time consuming and labor intensive. Why? Because it is not just a matter of technology but also of obtaining rough consensus if not full agreement amongst community members on the meaning and order of things. One way to develop these resources in a more automated way would be to use NLP/ML techniques to extract the required resources from large corpora of subject-specific text such as peer-reviewed papers where presumably a rough consensus has been achieved at least about the basics of the particular discipline involved. While not generally applied to Earth Sciences, considerable resources have been spent in other fields such as medicine on these types of techniques with some success. The NSF-funded ClearEarth project is applying the techniques developed for biomedicine to the cryosphere, geology, and biology in order to spur faster development of the semantic resources needed in these fields. The first area being addressed by the project is the cryosphere, specifically sea ice nomenclature where an existing set of sea ice ontologies are being used as the "Gold Standard" against which to test and validate the NLP/ML techniques. The processes being used, lessons learned and early results will be described.

  6. Applying Best Practices of the US-Russian Nuclear Security Cooperation to Advancing a Global Nuclear Security Agenda

    International Nuclear Information System (INIS)

    US-Russian cooperation in nuclear security provides valuable insight and recommendations on how to establish bilateral and multilateral cooperative programs to improve nuclear security in other regions. It also creates a potential for a joint US-Russian engagement in addressing global nuclear security needs, particularly in regions where resources and capacities are limited. These recommendations can promote success and sustainability for potential multilateral cooperation on nuclear security, including within the framework of the G-8 Global Partnership, UNSCR 1540 implementation, IAEA-led efforts and various bilateral and regional arrangements. With this goal in mind, the team of researchers from CENESS, CNS, and VCDNP examined the most successful US-Russian cooperative programs and nuclear security needs in Southeast Asia and former Soviet republics--two regions in need of further strengthening of nuclear security infrastructure and arrangements. They identified a number of areas in which the experience and expertise gained during US-Russian cooperative threat reduction efforts could provide the most valuable input to advancing nuclear security goals. The following five areas were identified: 1) education and training of nuclear security specialists, 2) legal and institutional framework developments, 3) border controls, 4) strategic trade controls, and 5) radiological source control and management. (author)

  7. Development of experimental apparatus for evaluating corrosion resistance of cladding materials applied for advanced power reactor. 1

    Energy Technology Data Exchange (ETDEWEB)

    Inohara, Yasuto; Ioka, Ikuo; Fukaya, Kiyoshi; Tachibana, Katsumi; Suzuki, Tomio; Kiuchi, Kiyoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kuroda, Yuji; Miyamoto, Satoshi [Japan Atomic Power Co., Tokyo (Japan)

    2001-03-01

    On the development of cladding materials for advanced power reactors, it is important to clarify long performance and to control the compatibility to high temperature water at heat conducting surfaces under heavy irradiation. On the present study, the high temperature water loop with an autoclave was made for examining the corrosion behavior up to the super critical water range and for developing the simulation testing technique under irradiation in the hot cell. The loop is applicable to immersion tests in the temperature and pressure ranges up to 450degC and 25 MPa that are covered the surface temperature range of fuel claddings. One of the characteristics of this apparatus is a pair of sapphire windows of autoclave for in-situ observations, and a phase transition from water to super critical water conditions was clearly verified through these windows. In this apparatus, it is possible to control the temperature, pressure and Dissolved Oxygen (DO) within a fluctuations of few % on three phases, namely, water, steam and super critical water. (author)

  8. Neutron scattering studies in thorium and uranium. Progress report, 1 September 1979-30 June 1980. [Dept. of Physics and Applied Physics, Univ. of Lowell, Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Beghian, L. E.; Kegel, G. H.R.

    1980-01-01

    Analysis of (n,n'..gamma..) measurements is now essentially complete, and level cross sections inferred from these data have been extracted for twenty-seven levels up to E/sub x/ = 1516 keV in /sup 238/U, and for thirty-seven levels up to E/sub x/ = 1738 keV in /sup 232/Th. One goal of the present work is to compare the level cross sections obtained from (n,n'..gamma..) with those from (n,n') measurements, to determine whether the former values are generally lower due, for example, to E0 contributions. Inelastic neutron scattering from high-lying states near 1 MeV excitation was measured in both /sup 232/Th and /sup 238/U, over the range of incident energies corresponding to the (n,n'..gamma..) studies. So far the results show no significant discrepancies between the (n,n'..gamma..) and (n,n') cross sections for most levels near theshold. Considerable progress was made on the near-threshold measurements of inelastically scattered neutrons from the 45-keV first excited state in /sup 238/U. These measurements were conducted using both the standard disk scatterer geometry and a ring scatterer with forward-angle geometry. These two very different techniques give cross sections in excellent agreement with one another; the measurement at 81 keV is the lowest energy measurement of this type published to date. Improved time resolution was also demonstrated using thin, ring-shaped scatterers at back angles. Data reduction capabilities have been further enhanced by the acquisition of several new peripherals. 17 figures, 1 table. (RWR)

  9. Detection of boiling by Piety's on-line PSD-pattern recognition algorithm applied to neutron noise signals in the SAPHIR reactor

    International Nuclear Information System (INIS)

    A partial blockage of the cooling channels of a fuel element in a swimming pool reactor could lead to vapour generation and to burn-out. To detect such anomalies, a pattern recognition algorithm based on power spectra density (PSD) proposed by Piety was further developed and implemented on a PDP 11/23 for on-line applications. This algorithm identifies anomalies by measuring the PSD on the process signal and comparing them with a standard baseline previously formed. Up to 8 decision discriminants help to recognize spectral changes due to anomalies. In our application, to detect boiling as quickly as possible with sufficient sensitivity, Piety's algorithm was modified using overlapped Fast-Fourier-Transform-Processing and the averaging of the PSDs over a large sample of preceding instantaneous PSDs. This processing allows high sensitivity in detecting weak disturbances without reducing response time. The algorithm was tested with simulation-of-boiling experiments where nitrogen in a cooling channel of a mock-up of a fuel element was injected. Void fractions higher than 30 % in the channel can be detected. In the case of boiling, it is believed that this limit is lower because collapsing bubbles could give rise to stronger fluctuations. The algorithm was also tested with a boiling experiment where the reactor coolant flow was actually reduced. The results showed that the discriminant D5 of Piety's algorithm based on neutron noise obtained from the existing neutron chambers of the reactor control system could sensitively recognize boiling. The detection time amounts to 7-30 s depending on the strength of the disturbances. Other events, which arise during a normal reactor run like scrams, removal of isotope elements without scramming or control rod movements and which could lead to false alarms, can be distinguished from boiling. 49 refs., 104 figs., 5 tabs

  10. Modern Trends in Neutron Activation Analysis. Applications to some African Environmental Samples

    International Nuclear Information System (INIS)

    This review covers the results of several published articles which deal with the modern trends in neutron activation analysis techniques using some of African research reactors for some environmental samples. The samples used have been collected from different areas in Egypt, South Africa, Ghana, Morocco, Nigeria, and Algeria. The neutron irradiation facilities and the advanced detection systems in each country are outlined. The prompt and delayed gamma-rays emitted due to neutron capture have been applied for investigation of the elemental constituents of such samples. Covered applications include exploration, mining, industrial environment, pollution of air, foodstuffs, soils and irrigation water samples. Some of the developed software programmes as well as the modern methods of data analysis are presented. The thermal and epithermal neutron activation analysis techniques have been applied for estimation of major, minor and trace elements in each material. Some of these data are presented with several comments.

  11. Neutron Compton Scattering

    OpenAIRE

    Watson, Greg

    1996-01-01

    Neutron Compton scattering measurements have the potential to provide direct information about atomic momentum distributions and adiabatic energy surfaces in condensed matter. First applied to measuring the condensate fraction in superfluid helium, the technique has recently been extended to study a variety of classical and quantum liquids and solids. This article reviews the theoretical background for the interpretation of neutron Compton scattering, with emphasis on studies of solids.

  12. Performance evaluation of different solar advanced oxidation processes applied to the treatment of a real textile dyeing wastewater.

    Science.gov (United States)

    Manenti, Diego R; Soares, Petrick A; Silva, Tânia F C V; Módenes, Aparecido N; Espinoza-Quiñones, Fernando R; Bergamasco, Rosângela; Boaventura, Rui A R; Vilar, Vítor J P

    2015-01-01

    The performance of different solar-driven advanced oxidation processes (AOPs), such as TiO2/UV, TiO2/H2O2/UV, and Fe(2+)/H2O2/UV-visible in the treatment of a real textile effluent using a pilot plant with compound parabolic collectors (CPCs), was investigated. The influence of the main photo-Fenton reaction variables such as iron concentration (20-100 mg Fe(2+) L(-1)), pH (2.4-4.5), temperature (10-50 °C), and irradiance (22-68 WUV m(-2)) was evaluated in a lab-scale prototype using artificial solar radiation. The real textile wastewater presented a beige color, with a maximum absorbance peak at 641 nm, alkaline pH (8.1), moderate organic content (dissolved organic carbon (DOC) = 129 mg C L(-1) and chemical oxygen demand (COD) = 496 mg O2 L(-1)), and high conductivity mainly associated to the high concentration of chloride (1.1 g Cl(-) L(-1)), sulfate (0.4 g SO 4 (2 -) L(- 1)), and sodium (1.2 g Na(+) L(-1)) ions. Although all the processes tested contributed to complete decolorization and effective mineralization, the most efficient process was the solar photo-Fenton with an optimum catalyst concentration of 60 mg Fe(2+) L(-1), leading to 70 % mineralization (DOCfinal = 41 mg C L(-1); CODfinal UV energy dose of 3.5 kJUV L(-1) (t 30 W = 22.4 min; [Formula: see text]; [Formula: see text]) and consuming 18.5 mM of H2O2.

  13. Performance evaluation of different solar advanced oxidation processes applied to the treatment of a real textile dyeing wastewater.

    Science.gov (United States)

    Manenti, Diego R; Soares, Petrick A; Silva, Tânia F C V; Módenes, Aparecido N; Espinoza-Quiñones, Fernando R; Bergamasco, Rosângela; Boaventura, Rui A R; Vilar, Vítor J P

    2015-01-01

    The performance of different solar-driven advanced oxidation processes (AOPs), such as TiO2/UV, TiO2/H2O2/UV, and Fe(2+)/H2O2/UV-visible in the treatment of a real textile effluent using a pilot plant with compound parabolic collectors (CPCs), was investigated. The influence of the main photo-Fenton reaction variables such as iron concentration (20-100 mg Fe(2+) L(-1)), pH (2.4-4.5), temperature (10-50 °C), and irradiance (22-68 WUV m(-2)) was evaluated in a lab-scale prototype using artificial solar radiation. The real textile wastewater presented a beige color, with a maximum absorbance peak at 641 nm, alkaline pH (8.1), moderate organic content (dissolved organic carbon (DOC) = 129 mg C L(-1) and chemical oxygen demand (COD) = 496 mg O2 L(-1)), and high conductivity mainly associated to the high concentration of chloride (1.1 g Cl(-) L(-1)), sulfate (0.4 g SO 4 (2 -) L(- 1)), and sodium (1.2 g Na(+) L(-1)) ions. Although all the processes tested contributed to complete decolorization and effective mineralization, the most efficient process was the solar photo-Fenton with an optimum catalyst concentration of 60 mg Fe(2+) L(-1), leading to 70 % mineralization (DOCfinal = 41 mg C L(-1); CODfinal < 150 mg O2 L(-1)) at pH 3.6, requiring a UV energy dose of 3.5 kJUV L(-1) (t 30 W = 22.4 min; [Formula: see text]; [Formula: see text]) and consuming 18.5 mM of H2O2. PMID:24737016

  14. Neutron optics requirements for neutron imaging techniques

    International Nuclear Information System (INIS)

    The utilization of X-rays for material research is common in many respects since their discovery at the end of the 19th century. New sources as electron synchrotrons or free-electron lasers push the methodology and the application ranges further. A similar approach started 50 years later with neutrons when sources with reasonable high intensity became available. Today, there are many similarities and complementarities visible between X-ray and neutron studies and the involved techniques. Therefore, it is worth to compare and to adapt from the advanced X-ray techniques and to translate it into the neutron world. Despite of the lack of neutron intensities compared to the most brilliant X-ray beams, the specific properties of neutrons (contrast, spin, magnetic moment, penetration power) are utilized and they will further play an important role in non-invasive studies on the micro- and macro scale. This paper wants to encourage to 'look over the fence' into activities of the X-ray community as currently running in the COST action MP-1203.

  15. Computational physics and applied mathematics capability review June 8-10, 2010 (Advance materials to committee members)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Stephen R [Los Alamos National Laboratory

    2010-01-01

    Los Alamos National Laboratory will review its Computational Physics and Applied Mathematics (CPAM) capabilities in 2010. The goals of capability reviews are to assess the quality of science, technology, and engineering (STE) performed by the capability, evaluate the integration of this capability across the Laboratory and within the scientific community, examine the relevance of this capability to the Laboratory's programs, and provide advice on the current and future directions of this capability. This is the first such review for CPAM, which has a long and unique history at the laboratory, starting from the inception of the Laboratory in 1943. The CPAM capability covers an extremely broad technical area at Los Alamos, encompassing a wide array of disciplines, research topics, and organizations. A vast array of technical disciplines and activities are included in this capability, from general numerical modeling, to coupled mUlti-physics simulations, to detailed domain science activities in mathematics, methods, and algorithms. The CPAM capability involves over 12 different technical divisions and a majority of our programmatic and scientific activities. To make this large scope tractable, the CPAM capability is broken into the following six technical 'themes.' These themes represent technical slices through the CP AM capability and collect critical core competencies of the Laboratory, each of which contributes to the capability (and each of which is divided into multiple additional elements in the detailed descriptions of the themes in subsequent sections): (1) Computational Fluid Dynamics - This theme speaks to the vast array of scientific capabilities for the simulation of fluids under shocks, low-speed flow, and turbulent conditions - which are key, historical, and fundamental strengths of the laboratory; (2) Partial Differential Equations - The technical scope of this theme is the applied mathematics and numerical solution of partial

  16. Neutron based evaluation in support of NEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, Sven C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bourke, Mark Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Losko, Adrian Simon [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-07

    The primary objective of the Advanced Non-Destructive fuel Examination (ANDE) work package is to develop capability that has the potential to accelerate insight and development of ceramic and metallic fuels. Establishing unique validation opportunities for new models is a key component of this effort. To explore opportunities a series of interactions were held with NEAMS modelers at LANL. The focus was to identify experiments that draw on the unique capabilities of neutron scattering and imaging for studies of nuclear fuel particularly in areas where experimental data can be valuable for of models validation. The neutron characterization techniques applied in the ANDE program span length scales from millimeter to micrometer to angstroms. Spatial heterogeneities of interest include cracks, pores and inclusions, crystal structure, phase composition, stoichiometry texture, chemistry and atomic thermal motion. Neutrons offer characterization opportunities that are distinct from other probes such as X-rays, electrons or protons. This report describes a variety of opportunities whereby neutron data can be related to models and lists some opportunities.

  17. Fast Neutron Resonance Radiography in a Pulsed Neutron Beam

    OpenAIRE

    Dangendorf, V.; Laczko, G; Kersten, C.; Jagutzki, O.; Spillmann, U

    2003-01-01

    The feasibility of performing fast neutron resonance radiography at the PTB accelerator facility is studied. A neutron beam of a broad spectral distribution is produced by a pulsed 13 MeV deuterium beam hitting a thick Be target. The potential of 3 different neutron imaging detectors with time-of flight capability are investigated. The applied methods comprise wire chambers with hydrogenous converter layers and a fast plastic scintillator with different optical readout schemes. We present the...

  18. Neutron radiography for maintenance inspection of military and civilian aircraft

    International Nuclear Information System (INIS)

    As part of a program to develop new and advanced nondestructive inspection techniques, a series of projects has been conducted to develop and evaluate neutron radiography as a nondestructive inspection tool. A major portion of this effort has been directed toward the application of neutron radiography as a maintenance inspection tool for military and civilian aircraft. The availability of 252Cf as a neutron source has enabled the use of neutron-radiography systems in normal maintenance environments for the inspection of flight-line aircraft with a minimum of interference. Neutron radiography has been demonstrated to be a powerful nondestructive inspection tool for a variety of applications involving the detection of organic or non-metallic compounds. Its ability to detect surface and subsurface corrosion in aircraft structure is unmatched by any other inspection technique. This capability of detecting corrosion without component disassembly is particularly significant when corrosion is hidden behind thick metallic structural members. The neutron radiographic technique has been applied successfully to detect corrosion in wing tanks, rear stabilators, aft spar, starboard and port wing, rudder, fuselage skin, and nose landing gears of a variety of fixed-wind aircraft, as well as rotary blades and rotary tail flaps of heliocopters

  19. Neutron Radiography

    Directory of Open Access Journals (Sweden)

    A. R. Reddy

    1982-07-01

    Full Text Available The field of neutron radiography with special reference to isotopic neutron radiography has been reviewed. Different components viz., sources, collimators, imaging systems are described. Various designs of neutron radiography facilities, their relative merits and demerits , the appropriateness of each design depending on the object to be radiographed, and economics of each technique are also dealt. The applications of neutron radiography are also briefly presented.

  20. In Situ Characterization Techniques Based on Synchrotron Radiation and Neutrons Applied for the Development of an Engineering Intermetallic Titanium Aluminide Alloy

    OpenAIRE

    Petra Erdely; Thomas Schmoelzer; Emanuel Schwaighofer; Helmut Clemens; Peter Staron; Andreas Stark; Klaus-Dieter Liss; Svea Mayer

    2016-01-01

    Challenging issues concerning energy efficiency and environmental politics require novel approaches to materials design. A recent example with regard to structural materials is the emergence of lightweight intermetallic TiAl alloys. Their excellent high-temperature mechanical properties, low density and high stiffness constitute a profile perfectly suitable for their application as advanced aero-engine turbine blades or as turbocharger turbine wheels in next-generation automotive engines. As ...

  1. An improved method for estimating the neutron background in measurements of neutron capture reactions

    CERN Document Server

    Žugec, P; Colonna, N; Gunsing, F

    2016-01-01

    The relation between the neutron background in neutron capture measurements and the neutron sensitivity related to the experimental setup is examined. It is pointed out that a proper estimate of the neutron background may only be obtained by means of dedicated simulations taking into account the full framework of the neutron-induced reactions and their complete temporal evolution. No other presently available method seems to provide reliable results, in particular under the capture resonances. An improved neutron background estimation technique is proposed, the main improvement regarding the treatment of the neutron sensitivity, taking into account the temporal evolution of the neutron-induced reactions. The technique is complemented by an advanced data analysis procedure based on relativistic kinematics of neutron scattering. The analysis procedure allows for the calculation of the neutron background in capture measurements, without requiring the time-consuming simulations to be adapted to each particular sa...

  2. Tratamiento del cáncer por captura neutrónica de boro: Su aplicación al carcinoma indiferenciado de tiroides Boron neutron capture therapy applied to undifferentiated thyroid carcinoma

    Directory of Open Access Journals (Sweden)

    Mario A. Pisarev

    2006-12-01

    studies we have shown a selective uptake of borophenylalanine (10BPA in a human UTC cell line (ARO and in NIH nude mice implanted with this cell line. When these animals were injected with BPA and irradiated with an appropriated neutron beam, we observed a 100% of tumor growth control and a 50 % of histological cure when the initial tumor volume was 50 mm³ or less. Further studies with BOPP (tetrakis-carborane carboxylate ester of 2,4-bis-(a, b-dihydroxyethyl-deutero-porphyrin IX showed that when this porphyrin was injected 5-7 days before BPA, and the animals were sacrificed 60 min after the i.p. injection of BPA, a significant increase in boron uptake by the tumor was found (45-38 ppm with both compounds vs. 20 ppm with BPA alone. The application of BNCT using the combination of boron compounds showed a 100% of complete remission in tumors with initial volumes under 50 mm³. Dogs suffer spontaneous UTC, with a similar biological behavior to the human tumor, and a selective uptake of BPA. These results open the possibility of applying BNCT to UTC.

  3. Neutron Capture and Neutron Halos

    OpenAIRE

    A.Mengoni; Otsuka, T; Nakamura, T.(International Center for Elementary Particle Physics and Department of Physics, The University of Tokyo, Tokyo, Japan); Ishihara, M.

    1996-01-01

    The connection between the neutron halo observed in light neutron rich nuclei and the neutron radiative capture process is outlined. We show how nuclear structure information such as spectroscopic factors and external components of the radial wave function of loosely bound states can be derived from the neutron capture cross section. The link between the direct radiative capture and the Coulomb dissociation process is elucidated.

  4. Neutrons for materials science

    International Nuclear Information System (INIS)

    The discussion will be limited to applied materials research performed on a customer/contractor basis. The information obtained using neutrons must therefore compete both scientifically and financially with information obtained using other techniques, particularly electron microscopy, X-ray, NMR, infra-red and Raman spectroscopy. It will be argued that the unique nature of the information gained from neutrons often outweighs the undoubted difficulties of access to neutron beams. Examples are given. Small angle scattering has emerged as the neutron technique of widest application in applied materials research. The penetration of neutron beams through containment vessels, as well as through the sample, allows the measurement of 'in situ' time dependent experiments within a furnace, cryostat, pressure vessel or chemical reactor vessel. High resolution powder diffraction is another technique with wide applications. Structural studies are possible on increasing complex phases. The structure and volume fraction of minority phases can be measured at levels appreciably below that possible by X-ray diffraction. A rapidly growing field at present is the measurement of internal strains through the small shifts in lattice spacing. Inelastic scattering measurements exploit the unique property of neutrons to measure the orientations of vibrating molecules. (author)

  5. THEHYCO-3DT: Thermal hydrodynamic code for the 3 dimensional transient calculation of advanced LMFBR core

    Energy Technology Data Exchange (ETDEWEB)

    Vitruk, S.G.; Korsun, A.S. [Moscow Engineering Physics Institute (Russian Federation); Ushakov, P.A. [Institute of Physics and Power Engineering, Obninsk (R)] [and others

    1995-09-01

    The multilevel mathematical model of neutron thermal hydrodynamic processes in a passive safety core without assemblies duct walls and appropriate computer code SKETCH, consisted of thermal hydrodynamic module THEHYCO-3DT and neutron one, are described. A new effective discretization technique for energy, momentum and mass conservation equations is applied in hexagonal - z geometry. The model adequacy and applicability are presented. The results of the calculations show that the model and the computer code could be used in conceptual design of advanced reactors.

  6. The intense neutron generator

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, W.B

    1966-07-01

    The presentation discusses both the economic and research contexts that would be served by producing neutrons in gram quantities at high intensities by electrical means without uranium-235. The revenue from producing radioisotopes is attractive. The array of techniques introduced by the multipurpose 65 megawatt Intense Neutron Generator project includes liquid metal cooling, superconducting magnets for beam bending and focussing, super-conductors for low-loss high-power radiofrequency systems, efficient devices for producing radiofrequency power, plasma physics developments for producing and accelerating hydrogen, ions at high intensity that are still far out from established practice, a multimegawatt high voltage D.C. generating machine that could have several applications. The research fields served relate principally to materials science through neutron-phonon and other quantum interactions as well as through neutron diffraction. Nuclear physics is served through {mu}-, {pi}- and K-meson production. Isotope production enters many fields of applied research. (author)

  7. An overview of DANCE: a 4II BaF[2] detector for neutron capture measurements at LANSCE.

    Energy Technology Data Exchange (ETDEWEB)

    Ullmann, J. L. (John L.)

    2004-01-01

    The Detector for Advanced Neutron Capture experiments (DANCE) is a 162-element, 4{pi} BaF{sub 2} array designed to make neutron capture cross-section measurements on rare or radioactive targets with masses as little as 1 mg. Accurate capture cross sections are needed in many research areas, including stellar nucleosynthesis, advanced nuclear fuel cycles, waste transmutation, and other applied programs. These cross sections are difficult to calculate accurately and must be measured. Up to now, except for a few long-lived nuclides there are essentially no differential capture measurements on radioactive nuclei. The DANCE array is located at the Lujan Neutron Scattering Center at LANSCE, which is a continuous-spectrum neutron source with useable energies from below thermal to about 100 keV. Data acquisition is done with 320 fast waveform digitizers. The design and initial performance results, including background minimization, will be discussed.

  8. An overview of DANCE: a 4π BaF2 detector for neutron capture measurements at LANSCE

    International Nuclear Information System (INIS)

    The Detector for Advanced Neutron Capture experiments (DANCE) is a 162-element, 4π BaF2 array designed to make neutron capture cross-section measurements on rare or radioactive targets with masses as little as 1 mg. Accurate capture cross sections are needed in many research areas, including stellar nucleosynthesis, advanced nuclear fuel cycles, waste transmutation, and other applied programs. These cross sections are difficult to calculate accurately and must be measured. Up to now, except for a few long-lived nuclides there are essentially no differential capture measurements on radioactive nuclei. The DANCE array is located at the Lujan Neutron Scattering Center at LANSCE, which is a continuous-spectrum neutron source with useable energies from below thermal to about 100 keV. Data acquisition is done with 320 fast waveform digitizers. The design and initial performance results, including background minimization, will be discussed.

  9. Neutron stress measurement using neutron image plate. 4

    International Nuclear Information System (INIS)

    A fundamental study on the neutron stress measurement using an image plate neutron detector was described. First, a method for determining internal mean stress over the area where incident beams pass through was explained. The method is based on the α angle method by which the stress analysis is conducted using information along a diffraction ring. Second, a neutron diffraction experiment was shown. This was conducted using the research reactor, JRR-3M, at Japan Atomic Energy Research Institute (JAERI). The 211 diffraction rings from steel sample were obtained using the image plate neutron detector. It was found that the mean stress obtained by the image plate agreed with stress applied. (author)

  10. Fast Neutron Resonance Radiography in a Pulsed Neutron Beam

    CERN Document Server

    Dangendorf, V; Kersten, C; Jagutzki, O; Spillmann, U

    2003-01-01

    The feasibility of performing fast neutron resonance radiography at the PTB accelerator facility is studied. A neutron beam of a broad spectral distribution is produced by a pulsed 13 MeV deuterium beam hitting a thick Be target. The potential of 3 different neutron imaging detectors with time-of flight capability are investigated. The applied methods comprise wire chambers with hydrogenous converter layers and a fast plastic scintillator with different optical readout schemes. We present the neutron facility, the imaging methods employed and results obtained. in beam experiments where samples of carbon rods with various length and diameter were imaged to study resolution and sensitivity of the method.

  11. Applying Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) spectral indices for geological mapping and mineral identification on the Tibetan Plateau

    CERN Document Server

    Corrie, Robert; Aitchison, Jonathan

    2011-01-01

    The Tibetan Plateau holds clues to understanding the dynamics and mechanisms associated with continental growth. Part of the region is characterized by zones of ophiolitic melange believed to represent the remnants of ancient oceanic crust and underlying upper mantle emplaced during oceanic closures. However, due to the remoteness of the region and the inhospitable terrain many areas have not received detailed investigation. Increased spatial and spectral resolution of satellite sensors have made it possible to map in greater detail the mineralogy and lithology than in the past. Recent work by Yoshiki Ninomiya of the Geological Survey of Japan has pioneered the use of several spectral indices for the mapping of quartzose, carbonate, and silicate rocks using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) thermal infrared (TIR) data. In this study, ASTER TIR indices have been applied to a region in western-central Tibet for the purposes of assessing their effectiveness for differentiatin...

  12. Airline return-on-investment model for technology evaluation. [computer program to measure economic value of advanced technology applied to passenger aircraft

    Science.gov (United States)

    1974-01-01

    This report presents the derivation, description, and operating instructions for a computer program (TEKVAL) which measures the economic value of advanced technology features applied to long range commercial passenger aircraft. The program consists of three modules; and airplane sizing routine, a direct operating cost routine, and an airline return-on-investment routine. These modules are linked such that they may be operated sequentially or individually, with one routine generating the input for the next or with the option of externally specifying the input for either of the economic routines. A very simple airplane sizing technique was previously developed, based on the Brequet range equation. For this program, that sizing technique has been greatly expanded and combined with the formerly separate DOC and ROI programs to produce TEKVAL.

  13. Education and training for advanced practice: Principles of course design and assessment applied to a 'stereotactic needle core biopsy of the breast' module

    International Nuclear Information System (INIS)

    In order to realise the promise of the NHS Plan, radiographers are extending their practice to encompass tasks previously undertaken by radiologists and advancing their practice by taking responsibility for clinical decision-making and autonomous membership of multidisciplinary healthcare teams. In partnership with clinical service providers Higher Education Institutes are devising programmes of study to support such professional development. This article reviews the design of a 20 credit post-graduate (M level) module in stereotactic needle core biopsy of the breast. Particular consideration is given to underpinning educational principles of course design and assessment and how these are applied in order that teaching, learning and assessment have academic rigour and clinical competence of successful students is assured

  14. Education and training for advanced practice: Principles of course design and assessment applied to a 'stereotactic needle core biopsy of the breast' module

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, Anne-Marie [Division of Radiography, University of Bradford, Bradford BD5 0BB (United Kingdom)]. E-mail: a.m.dixon@bradford.ac.uk

    2006-05-15

    In order to realise the promise of the NHS Plan, radiographers are extending their practice to encompass tasks previously undertaken by radiologists and advancing their practice by taking responsibility for clinical decision-making and autonomous membership of multidisciplinary healthcare teams. In partnership with clinical service providers Higher Education Institutes are devising programmes of study to support such professional development. This article reviews the design of a 20 credit post-graduate (M level) module in stereotactic needle core biopsy of the breast. Particular consideration is given to underpinning educational principles of course design and assessment and how these are applied in order that teaching, learning and assessment have academic rigour and clinical competence of successful students is assured.

  15. Neutron diffraction studies of magnetic ordering in superconducting ErNi2B2C and TmNi2B2C in an applied magnetic field

    DEFF Research Database (Denmark)

    Toft, Katrine Nørgaard

    The field-induced magnetic structures of ErNi2B2C and TmNi2B2C in are especially interesting because the field suppresses the superconducting order parameter and therefore the magnetic properties can be studied while varying the strength ofsuperconductivity. ErNi2B2C: For magnetic fields along all...... three symmetry directions, the observed magnetic structures have a period corresponding to the Fermi surface nesting structure. The phase diagrams present all the observed magnetic structures.Two results remain unresolved: 1. When applying the magnetic field along [010], the minority domain (QNB = (0,Q......,0) with moments perpendicular to the field) shows no signs of hysteresis. I expected it to be a meta-stable state, which would be graduallysuppressed by a magnetic field, and when decreasing the field it would not reappear until some small field of approximately 0.1 T. 2. When the field is applied...

  16. 2010 Neutron Review: ORNL Neutron Sciences Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Bardoel, Agatha A [ORNL; Counce, Deborah M [ORNL; Ekkebus, Allen E [ORNL; Horak, Charlie M [ORNL; Nagler, Stephen E [ORNL; Kszos, Lynn A [ORNL

    2011-06-01

    During 2010, the Neutron Sciences Directorate focused on producing world-class science, while supporting the needs of the scientific community. As the instrument, sample environment, and data analysis tools at High Flux Isotope Reactor (HFIR ) and Spallation Neutron Source (SNS) have grown over the last year, so has promising neutron scattering research. This was an exciting year in science, technology, and operations. Some topics discussed are: (1) HFIR and SNS Experiments Take Gordon Battelle Awards for Scientific Discovery - Battelle Memorial Institute presented the inaugural Gordon Battelle Prizes for scientific discovery and technology impact in 2010. Battelle awards the prizes to recognize the most significant advancements at national laboratories that it manages or co-manages. (2) Discovery of Element 117 - As part of an international team of scientists from Russia and the United States, HFIR staff played a pivotal role in the discovery by generating the berkelium used to produce the new element. A total of six atoms of ''ununseptium'' were detected in a two-year campaign employing HFIR and the Radiochemical Engineering Development Center at Oak Ridge National Laboratory (ORNL) and the heavy-ion accelerator capabilities at the Joint Institute for Nuclear Research in Dubna, Russia. The discovery of the new element expands the understanding of the properties of nuclei at extreme numbers of protons and neutrons. The production of a new element and observation of 11 new heaviest isotopes demonstrate the increased stability of super-heavy elements with increasing neutron numbers and provide the strongest evidence to date for the existence of an island of enhanced stability for super-heavy elements. (3) Studies of Iron-Based High-Temperature Superconductors - ORNL applied its distinctive capabilities in neutron scattering, chemistry, physics, and computation to detailed studies of the magnetic excitations of iron-based superconductors (iron

  17. Calibration of the IRD two-component TLD albedo neutron dosemeter in some moderated neutron fields

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Bruno M.; Silva, Ademir X. da, E-mail: bfreitas@nuclear.ufrj.br, E-mail: ademir@nuclear.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Martins, Marcelo M.; Pereira, Walsan W.; Mauricio, Claudia L.P., E-mail: marcelo@ird.gov.br, E-mail: walsan@ird.gov.br, E-mail: claudia@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    In some stray neutron fields, like those found in practices involving the handling of radionuclide sources, the neutron calibration factor for albedo neutron dosemeter can vary widely compared to the factor for bare sources. This is the case for well logging, which is the area with the largest number of workers exposed to neutrons in Brazil. The companies employ routinely {sup 241}Am-Be neutron sources. The albedo response variation is mainly due to the presence of scattered and moderated neutrons. This paper studies the response variation of the two-component TLD albedo neutron dosemeter used in the neutron individual monitoring service of Instituto de Radioprotecao e Dosimetria, in different radionuclide neutron source beams. The neutron spectra were evaluated applying a Bonner sphere spectrometer with a {sup 6}LiI(Eu) detector in the Brazilian National Metrology Neutron Laboratory. Standard neutron sources of {sup 241}Am-Be and {sup 252}Cf were employed, besides {sup 238}Pu-Be. Measurements were also made with scattered and moderated neutron beams, including {sup 252}Cf(D{sub 2}O) reference spectrum, {sup 241}Am-Be moderated with paraffin and silicone and a thermal neutron flux facility. New neutron calibration factors, as a function of the incident to albedo neutron ratio, were proposed for use in the albedo algorithm for occupational fields where the primary neutron beam is one of those studied sources. (author)

  18. Fundamental of neutron radiography and the present of neutron radiography in Japan

    International Nuclear Information System (INIS)

    Neutron radiography refers to the application of transmitted neutrons to analysis. In general, thermal neutron is used for neutron radiography. Thermal neutron is easily absorbed by light atoms, including hydrogen, boron and lithium, while it is not easily absorbed by such heavy atoms as tungsten, lead and uranium, permitting detection of impurities in heavy metals. Other neutrons than thermal neutron can also be applied. Cold neutron is produced from fast neutron using a moderator to reduce its energy down to below that of thermal neutron. Cold neutron is usefull for analysis of thick material. Epithermal neutron can induce resonance characteristic of each substance. With a relatively small reaction area, fast neutron permits observation of thick samples. Being electrically neutral, neutrons are difficult to detect by direct means. Thus a substance that releases charged particles is put in the path of neutrons for indirect measurement. X-ray film combined with converter screen for conversion of neutrons to charge particles is placed behind the sample. Photographing is carried out by a procedure similar to X-ray photography. Major institues and laboratories in Japan provided with neutron radiography facilities are listed. (Nogami, K.)

  19. Apparatus for measuring a flux of neutrons

    Science.gov (United States)

    Stringer, James L.

    1977-01-01

    A flux of neutrons is measured by disposing a detector in the flux and applying electronic correlation techniques to discriminate between the electrical signals generated by the neutron detector and the unwanted interfering electrical signals generated by the incidence of a neutron flux upon the cables connecting the detector to the electronic measuring equipment at a remote location.

  20. Development of fast neutron pinhole camera using nuclear emulsion for neutron emission profile measurement in KSTAR

    Science.gov (United States)

    Izumi, Y.; Tomita, H.; Nakayama, Y.; Hayashi, S.; Morishima, K.; Isobe, M.; Cheon, M. S.; Ogawa, K.; Nishitani, T.; Naka, T.; Nakano, T.; Nakamura, M.; Iguchi, T.

    2016-11-01

    We have developed a compact fast neutron camera based on a stack of nuclear emulsion plates and a pinhole collimator. The camera was installed at J-port of Korea superconducting tokamak advanced research at National Fusion Research Institute, Republic of Korea. Fast neutron images agreed better with calculated ones based on Monte Carlo neutron simulation using the uniform distribution of Deuterium-Deuterium (DD) neutron source in a torus of 40 cm radius.

  1. Neutron diffraction studies of magnetic ordering in superconducting ErNi2B2C and TmNi2B2C in an applied magnetic field

    International Nuclear Information System (INIS)

    The field-induced magnetic structures of ErNi2B2C and TmNi2B2C in are especially interesting because the field suppresses the superconducting order parameter and therefore the magnetic properties can be studied while varying the strength of superconductivity. ErNi2B2C: For magnetic fields along all three symmetry directions, the observed magnetic structures have a period corresponding to the Fermi surface nesting structure. The phase diagrams present all the observed magnetic structures. Two results remain unresolved: 1. When applying the magnetic field along [010], the minority domain (QNB = (0,Q,0) with moments perpendicular to the field) shows no signs of hysteresis. I expected it to be a meta-stable state, which would be gradually suppressed by a magnetic field, and when decreasing the field it would not reappear until some small field of approximately 0.1 T. 2. When the field is applied along [110], the magnetic structure rotates a small angle of 0.5 degrees away from the symmetry direction. TmNi2B2C: A magnetic field applied in the [100] direction suppresses the zero field magnetic structure QF = (0.094,0.094,0) (TN = 1.6 K), in favor of the Fermi surface nesting structure QN = (0.483,0,0). The appearance of the QN phase was initially believed to be caused by the suppression of superconductivity. This suppression should make it favorable to create a magnetic order with a Q-vector determined by the maximum in the magnetic susceptibility at the Fermi surface nesting vector QN. The phase diagram for the magnetic structures is presented, however several properties of the QN magnetic structure cannot be explained within any known models. Quadrupolar ordering is suggested as a possible candidate for explaining these features of the QN structure. (au)

  2. Neutron detector

    Science.gov (United States)

    Stephan, Andrew C.; Jardret; Vincent D.

    2011-04-05

    A neutron detector has a volume of neutron moderating material and a plurality of individual neutron sensing elements dispersed at selected locations throughout the moderator, and particularly arranged so that some of the detecting elements are closer to the surface of the moderator assembly and others are more deeply embedded. The arrangement captures some thermalized neutrons that might otherwise be scattered away from a single, centrally located detector element. Different geometrical arrangements may be used while preserving its fundamental characteristics. Different types of neutron sensing elements may be used, which may operate on any of a number of physical principles to perform the function of sensing a neutron, either by a capture or a scattering reaction, and converting that reaction to a detectable signal. High detection efficiency, an ability to acquire spectral information, and directional sensitivity may be obtained.

  3. Statistical Uncertainty in Quantitative Neutron Radiography

    OpenAIRE

    Piegsa, Florian M.; Kaestner, Anders P.

    2016-01-01

    We demonstrate a novel procedure to calibrate neutron detection systems commonly used in standard neutron radiography. This calibration allows determining the uncertainties due to Poisson-like neutron counting statistics for each individual pixel of a radiographic image. The obtained statistical errors are necessary in order to perform correct quantitative analysis. This fast and convenient method is applied to real data measured at the cold neutron radiography facility ICON at the Paul Scher...

  4. Attitude-adjusting table for neutron monochromator

    International Nuclear Information System (INIS)

    The neutron monochromator attitude-adjusting table is one of the mechanical components for most monochromatic neutron scattering spectrometer. It is mainly used for mounting crystal monochromator, and getting monochromatic neutron by adjusting the attitude of monochromator remotely. The table has a compact volume and five adjusting axes with high resolution. It combines optic mechanical electronic technique with computer control technique. This device will be applied to the neutron residual stress spectrometer on CARR firstly. (authors)

  5. Advanced materials characterization and modeling using synchrotron, neutron, TEM, and novel micro-mechanical techniques - A European effort to accelerate fusion materials development

    DEFF Research Database (Denmark)

    Linsmeier, Ch.; Fu, C.-C.; Kaprolat, A.;

    2013-01-01

    For the realization of fusion as an energy source, the development of suitable materials is one of the most critical issues. The required material properties are in many aspects unique compared to the existing solutions, particularly the need for necessary resistance to irradiation with neutrons ...

  6. Atmospheric neutrons

    International Nuclear Information System (INIS)

    Additional calibrations of the University of California double-scatter neutron and additional analysis corrections lead to the slightly changed neutron fluxes reported here. The theoretical angular distributions of Merker (1975) are in general agreement with our experimental fluxes but do not give the peaks for vertical upward and downward moving neutrons. The theoretical neutron escape current J2/sub pi/ (Merker, 1972; Armstrong et al., 1973) is in agreement with the experimental values from 10 to 100 MeV. Our experimental fluxes agree with those of the Kanbach et al. (1974) in the overlap region from 70 to 100 MeV

  7. Experiment Design and Analysis Guide - Neutronics & Physics

    Energy Technology Data Exchange (ETDEWEB)

    Misti A Lillo

    2014-06-01

    The purpose of this guide is to provide a consistent, standardized approach to performing neutronics/physics analysis for experiments inserted into the Advanced Test Reactor (ATR). This document provides neutronics/physics analysis guidance to support experiment design and analysis needs for experiments irradiated in the ATR. This guide addresses neutronics/physics analysis in support of experiment design, experiment safety, and experiment program objectives and goals. The intent of this guide is to provide a standardized approach for performing typical neutronics/physics analyses. Deviation from this guide is allowed provided that neutronics/physics analysis details are properly documented in an analysis report.

  8. Neutron imaging in materials science

    Directory of Open Access Journals (Sweden)

    Nikolay Kardjilov

    2011-06-01

    Full Text Available Neutron imaging is a non-destructive technique that can reveal the interior of many materials and engineering components and also probe magnetic fields. Within the past few years, several new imaging modes have been introduced that extend the scope of neutron imaging beyond conventional neutron attenuation imaging, yielding both 2- and 3D information about properties and phenomena inaccessible until now. We present an overview of the most important advances in the application of neutron imaging in materials research with a focus on novel techniques such as energy-selective imaging, interferometric imaging with phase gratings, and polarized-neutron imaging. Examples given include the investigation of fluid dynamics in fuel cells, materials phases and structural heterogeneities, distribution of strains, and magnetic structures or phase transitions.

  9. Neutron capture reactions at DANCE

    International Nuclear Information System (INIS)

    The Detector for Advanced Neutron Capture Experiments (DANCE) is a 4π BaF2 array consisting of 160 active detector elements. The primary purpose of the array is to perform neutron capture cross section measurements on small (> or approx.100 μg) and/or radioactive (241,243Am, neutron capture and neutron-induced fission cross sections and capture-to-fission ratio (α = σγ/σf) for 235U using a new fission-tagging detector as well as neutron capture cross sections for several astrophysics branch-point nuclei. Results from several of these measurements will be presented along with a discussion of additional physics information that can be extracted from the DANCE data

  10. Neutron Computed Tomography of Freeze/thaw Phenomena in Polymer Electrolyte Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Matthew M. Mech; Jack Brenizer; Kenan Unlu; A.K. Heller

    2008-12-12

    This report summarizes the final year's progress of the three-year NEER program. The overall objectives of this program were to 1) design and construct a sophisticated hight-resolution neutron computed tomography (NCT) facility, 2) develop novel and sophisticated liquid water and ice quantification analysis software for computed tomography, and 3) apply the advanced software and NCT capability to study liquid and ice distribution in polymer electrolyte fuel cells (PEFCs) under cold-start conditions. These objectives have been accomplished by the research team, enabling a new capability for advanced 3D image quantification with neutron imaging for fuel cell and other applications. The NCT water quantification methodology and software will greatly add to the capabilities of the neutron imaging community, and the quantified liquid water and ice distribution provided by its application to PEFCs will enhance understanding and guide design in the fuel cell community.

  11. The intense neutron generator and future factory type ion accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, W.B

    1968-07-01

    A neutron factory is likely to sell its product in the form of isotopes. To ay neutron factories are nuclear reactors. Ion accelerators may also produce isotopes by direct interaction and, at high enough energies, mesons and hyperons. The challenge of the electrical production of neutrons goes far beyond the isotope market. It challenges the two popular concepts for long term large scale energy, the fast breeder reactor and controlled thermonuclear fusion. For this use about 4% of nuclear generated power would be applied in a feedback loop generating extra neutrons. Competition rests on operating and processing costs. The Intense Neutron Generator proposal now cancelled would have been full scale for such a use, but much further advance in accelerator engineering is required and anticipated. Perhaps most promising is the application of the ion drag principle in which rings of fast electrons are accelerated along their axis dragging ions with them by electrostatic attraction. Due to the much larger mass of the ions they can acquire much higher energy than the electrons and the process could be efficient. Such accelerators have not yet been made but experimental and theoretical studies are promising. (author)

  12. The intense neutron generator and future factory type ion accelerators

    International Nuclear Information System (INIS)

    A neutron factory is likely to sell its product in the form of isotopes. To ay neutron factories are nuclear reactors. Ion accelerators may also produce isotopes by direct interaction and, at high enough energies, mesons and hyperons. The challenge of the electrical production of neutrons goes far beyond the isotope market. It challenges the two popular concepts for long term large scale energy, the fast breeder reactor and controlled thermonuclear fusion. For this use about 4% of nuclear generated power would be applied in a feedback loop generating extra neutrons. Competition rests on operating and processing costs. The Intense Neutron Generator proposal now cancelled would have been full scale for such a use, but much further advance in accelerator engineering is required and anticipated. Perhaps most promising is the application of the ion drag principle in which rings of fast electrons are accelerated along their axis dragging ions with them by electrostatic attraction. Due to the much larger mass of the ions they can acquire much higher energy than the electrons and the process could be efficient. Such accelerators have not yet been made but experimental and theoretical studies are promising. (author)

  13. Texture analysis at neutron diffractometer STRESS-SPEC

    Science.gov (United States)

    Brokmeier, H.-G.; Gan, W. M.; Randau, C.; Völler, M.; Rebelo-Kornmeier, J.; Hofmann, M.

    2011-06-01

    In response to the development of new materials and the application of materials and components in advanced technologies, non-destructive measurement methods of textures and residual stresses have gained worldwide significance in recent years. The materials science neutron diffractometer STRESS-SPEC at FRM II (Garching, Germany) is designed to be applied equally to texture and residual stress analyses by virtue of its very flexible configuration. Due to the high penetration capabilities of neutrons and the high neutron flux of STRESS-SPEC it allows a combined analysis of global texture, local texture, strain pole figure and FWHM pole figure in a wide variety of materials including metals, alloys, composites, ceramics and geological materials. Especially, the analysis of texture gradients in bulk materials using neutron diffraction has advantages over laboratory X-rays and EBSD for many scientific cases. Moreover, neutron diffraction is favourable for coarse-grained materials, where bulk information averaged over texture inhomogeneities is needed, and also stands out due to easy sample preparation. In future, the newly developed robot system for STRESS-SPEC will allow much more flexibility than an Eulerian cradle as on standard instruments. Five recent measurements are shown to demonstrate the wide range of possible texture applications at STRESS-SPEC diffractometer.

  14. Neutron dosimetry; Dosimetria de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Fratin, Luciano

    1993-12-31

    A neutron irradiation facility was designed and built in order to establish a procedure for calibrating neutron monitors and dosemeters. A 185 GBq {sup 241} Am Be source of known is used as a reference source. The irradiation facility using this source in the air provides neutron dose rates between 9 nSv s{sup -1} and 0,5 {sup {mu}}Sv s{sup -1}. A calibrated 50 nSv s{sup -1} thermal neutron field is obtained by using a specially designed paraffin block in conjunction with the {sup 241} Am Be source. A Bonner multisphere spectrometer was calibrated, using a procedure based on three methods proposed by international standards. The unfold {sup 241} Am Be neutron spectrum was determined from the Bonner spheres data and resulted in a good agreement with expected values for fluence rate, dose rate and mean energy. A dosimetric system based on the electrochemical etching of CR-39 was developed for personal dosimetry. The dosemeter badge using a (n,{alpha}) converter, the etching chamber and high frequency power supply were designed and built specially for this project. The electrochemical etching (ECE) parameters used were: a 6N KOH solution, 59 deg C, 20 kV{sub pp} cm{sup -1}, 2,0 kHz, 3 hours of ECE for thermal and intermediate neutrons and 6 hours for fast neutrons. The calibration factors for thermal, intermediate and fast neutrons were determined for this personal dosemeter. The sensitivities determined for the developed dosimetric system were (1,46{+-} 0,09) 10{sup 4} tracks cm{sup -2} mSv{sup -1} for thermal neutrons, (9{+-}3) 10{sup 2} tracks cm{sup -2} mSV{sup -1} for intermediate neutrons and (26{+-}4) tracks cm{sup -2} mSv{sup -1} for fast neutrons. The lower and upper limits of detection were respectively 0,002 mSv and 0,6 mSv for thermal neutrons, 0,04 mSv and 8 mSv for intermediate neutrons and 1 mSv and 12 mSv for fast neutrons. In view of the 1990`s ICRP recommendations, it is possible to conclude that the personal dosemeter described in this work is

  15. Gravitoastronomy with neutron stars

    OpenAIRE

    Woan, G.

    2005-01-01

    Recent advances in gravitational wave detectors mean that we can start to make astrophysically important statements about the physics of neutron stars based on observed upper limits to their gravitational luminosity. Here we consider statements we can already make about a selection of known radio pulsars, based on data from the LIGO and GEO600 detectors, and look forward to what could be learned from the first detections.

  16. Neutron tubes

    Science.gov (United States)

    Leung, Ka-Ngo; Lou, Tak Pui; Reijonen, Jani

    2008-03-11

    A neutron tube or generator is based on a RF driven plasma ion source having a quartz or other chamber surrounded by an external RF antenna. A deuterium or mixed deuterium/tritium (or even just a tritium) plasma is generated in the chamber and D or D/T (or T) ions are extracted from the plasma. A neutron generating target is positioned so that the ion beam is incident thereon and loads the target. Incident ions cause D-D or D-T (or T-T) reactions which generate neutrons. Various embodiments differ primarily in size of the chamber and position and shape of the neutron generating target. Some neutron generators are small enough for implantation in the body. The target may be at the end of a catheter-like drift tube. The target may have a tapered or conical surface to increase target surface area.

  17. Spallation Neutrons Used for Imaging in the Time and Energy Domain

    International Nuclear Information System (INIS)

    SINQ, the Swiss national source for neutron research, is based on the principle of spallation, where protons from a 590 MeV cyclotron are sent to a lead target with highest possible beam intensity. The proton beam current from the PSI’s cyclotron is of the order of 2 mA, corresponding to about 1 MW deposited beam power in the target region. SINQ is a large scale user facility. The spallation neutrons with initial energies of up to 100 MeV are slowed to thermal energies within the moderator tank filled with heavy water (D2O). Further reduction of the neutron energy can take place in the cold source, which is operated at about 25 K and is filled with liquid deuterium. Unlike similar spallation sources (SNS, Oak Ridge, United States of America; JPARC, Tokai, Japan; ISIS, Didcot, United Kingdom), SINQ is not a pulsed source but provides a constant neutron flux level. As such, it compares to a research reactor with about 15 MW of thermal power. Neutron imaging as an advanced technique for neutron research, applied studies and industrial testing is established at SINQ with two beamlines: NEUTRA for thermal neutrons and ICON for cold neutrons. This capability has only minor representation compared to the scattering facilities at SINQ, with about 15 such installations. Modern neutron imaging techniques are exclusively based on digital systems, where each pixel can be considered an individual neutron counter. Neutron imaging experiments are mainly performed in transmission mode where the comparison between the initial and transmitted radiation is used to describe the properties of the sample material in the beam. For standard applications, the full incident neutron spectrum is used, which delivers an energy average attenuation value. Recent developments at the SINQ imaging beamlines permit time dependent investigations, in particular of cyclic processes, with frames in the millisecond range. This option is of high interest for studying the injection of fuel into running

  18. Georgia Tech Studies of Sub-Critical Advanced Burner Reactors with a D-T Fusion Tokamak Neutron Source for the Transmutation of Spent Nuclear Fuel

    Science.gov (United States)

    Stacey, W. M.

    2009-09-01

    The possibility that a tokamak D-T fusion neutron source, based on ITER physics and technology, could be used to drive sub-critical, fast-spectrum nuclear reactors fueled with the transuranics (TRU) in spent nuclear fuel discharged from conventional nuclear reactors has been investigated at Georgia Tech in a series of studies which are summarized in this paper. It is found that sub-critical operation of such fast transmutation reactors is advantageous in allowing longer fuel residence time, hence greater TRU burnup between fuel reprocessing stages, and in allowing higher TRU loading without compromising safety, relative to what could be achieved in a similar critical transmutation reactor. The required plasma and fusion technology operating parameter range of the fusion neutron source is generally within the anticipated operational range of ITER. The implications of these results for fusion development policy, if they hold up under more extensive and detailed analysis, is that a D-T fusion tokamak neutron source for a sub-critical transmutation reactor, built on the basis of the ITER operating experience, could possibly be a logical next step after ITER on the path to fusion electrical power reactors. At the same time, such an application would allow fusion to contribute to meeting the nation's energy needs at an earlier stage by helping to close the fission reactor nuclear fuel cycle.

  19. Constraining the neutron star equation of state with gravitational wave signals from coalescing binary neutron stars

    CERN Document Server

    Agathos, Michalis; Del Pozzo, Walter; Li, Tjonnie G F; Tompitak, Marco; Veitch, John; Vitale, Salvatore; Broeck, Chris Van Den

    2015-01-01

    Recently exploratory studies were performed on the possibility of constraining the neutron star equation of state (EOS) using signals from coalescing binary neutron stars, or neutron star-black hole systems, as they will be seen in upcoming advanced gravitational wave detectors such as Advanced LIGO and Advanced Virgo. In particular, it was estimated to what extent the combined information from multiple detections would enable one to distinguish between different equations of state through hypothesis ranking or parameter estimation. Under the assumption of zero neutron star spins both in signals and in template waveforms and considering tidal effects to 1PN order, it was found that O(20) sources would suffice to distinguish between a hard, moderate, and soft equation of state. Here we revisit these results, this time including neutron star tidal effects to the highest order currently known, termination of gravitational waveforms at the contact frequency, neutron star spins, and the resulting quadrupole-monopo...

  20. Current status of neutron activation analysis in HANARO Research Reactor

    International Nuclear Information System (INIS)

    The facilities for neutron activation analysis in the HANARO (Hi-flux Advanced Neutron Application Research Reactor) are described and the main applications of NAA (Neutron Activation Analysis) are reviewed. The sample irradiation tube, automatic and manual pneumatic transfer system were installed at three irradiation holes of HANARO at the end of 1995. The performance of the NAA facility was examined to identify the characteristics of the tube transfer system, irradiation sites and custom-made polyethylene irradiation capsule. The available thermal neutron fluxes at irradiation sites are in the range of 3 x 1013 - 1 x 1014 n/cm2·s and cadmium ratios are in 15 - 250. For an automatic sample changer for gamma-ray counting, a domestic product was designed and manufactured. An integrated computer program (Labview) to analyse the content was developed. In 2001, PGNAA (Prompt Gamma Neutron Activation Analysis) facility has been installed using a diffracted neutron beam of ST1. NAA has been applied in the trace component analysis of nuclear, geological, biological, environmental and high purity materials, and various polymers for research and development. The improvement of analytical procedures and establishment of an analytical quality control and assurance system were studied. Applied research and development for the environment, industry and human health by NAA and its standardization were carried out. For the application of the KOLAS (Korea Laboratory Accreditation Scheme), evaluation of measurement uncertainty and proficiency testing of reference materials were performed. Also to verify the reliability and to validate analytical results, intercomparison studies between laboratories were carried out. (author)

  1. Current status of neutron activation analysis in HANARO Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Yong Sam; Moon, Jong Hwa; Sohn, Jae Min [Korea Atomic Energy Research Institute, Daejeon (Korea)

    2003-03-01

    The facilities for neutron activation analysis in the HANARO (Hi-flux Advanced Neutron Application Research Reactor) are described and the main applications of NAA (Neutron Activation Analysis) are reviewed. The sample irradiation tube, automatic and manual pneumatic transfer system were installed at three irradiation holes of HANARO at the end of 1995. The performance of the NAA facility was examined to identify the characteristics of the tube transfer system, irradiation sites and custom-made polyethylene irradiation capsule. The available thermal neutron fluxes at irradiation sites are in the range of 3 x 10{sup 13} - 1 x 10{sup 14} n/cm{sup 2}{center_dot}s and cadmium ratios are in 15 - 250. For an automatic sample changer for gamma-ray counting, a domestic product was designed and manufactured. An integrated computer program (Labview) to analyse the content was developed. In 2001, PGNAA (Prompt Gamma Neutron Activation Analysis) facility has been installed using a diffracted neutron beam of ST1. NAA has been applied in the trace component analysis of nuclear, geological, biological, environmental and high purity materials, and various polymers for research and development. The improvement of analytical procedures and establishment of an analytical quality control and assurance system were studied. Applied research and development for the environment, industry and human health by NAA and its standardization were carried out. For the application of the KOLAS (Korea Laboratory Accreditation Scheme), evaluation of measurement uncertainty and proficiency testing of reference materials were performed. Also to verify the reliability and to validate analytical results, intercomparison studies between laboratories were carried out. (author)

  2. Boron neutron capture therapy (BNCT) using fast neutrons: Effects in two human tumor cell lines

    International Nuclear Information System (INIS)

    The results demonstrate that the effect of fast neutrons on cell survival in cell culture can be enhanced by boron neutron capture reaction. Even with lower enhancement ratios, the concept of NCT assisted fast neutron therapy may successfully be applied for tumor treatment with the Essen cyclotron. (orig.)

  3. 先进裂变核能的关键核数据测量和CSNS白光中子源%Key Nuclear Data Measurements for Advanced Fission Energy and White Neutron Source at CSNS

    Institute of Scientific and Technical Information of China (English)

    唐靖宇; 敬罕涛; 夏海鸿; 唐洪庆; 张闯; 周祖英; 阮锡超; 张奇玮; 杨征

    2013-01-01

    在设计加速器驱动的次临界系统(ADS)、核废料嬗变装置及钍基熔盐堆时亟需一些关键核数据,当前核数据库受实验条件或中子能区的限制,存在核数据精度不高甚至少部分核素数据缺失的情况.本文综述了国内外相关的核数据研究和相应的白光中子源情况.基于中国散裂中子源(CSNS)的反角通道白光中子源实验终端的中子束流具有非常宽的能谱(0.01 eV~200 MeV)和很好的时间特性.模拟得到距靶80 m处的实验终端的中子注量率为9.3×106 cm-2·s-1,1 eV~1 MeV能量间隔内的中子数占总中子数的53%;同时,加速器运行在双束团模式或单束团模式,时间分辨率均在0.3%~0.9%之间,适合开展核数据测量.%The key nuclear data for advanced fission energy are important in designing advanced nuclear reactors and facilities for nuclear-waste transmutation.Because the present nuclear data library is limited by experimental condition and energy range,the precision of some nuclear data is low,even some nuclear data are blank.In this paper,the status of the nuclear data and white neutron sources were presented.The backstreaming neutron beam at China Spallation Neutron Source (CSNS) has very wide energy spectrum (0.01 eV-200 MeV) and excellent time structure.From the simulation results,it's obtained that the uncollimated neutron fluence rate is around 9.3 ×106 cm-2 · s-1 within the given energy range at 80 m away from the target,which accounts for about 53% of the total neutrons.The time resolution of 0.3%-0.9%,which is important for the Time-of-Flight method,can be obtained for both the parasite operation mode with two proton bunches and the dedicated operation mode with a single proton bunch.CSNS white neutron source will be a good facility for nuclear data measurement.

  4. Neutron radiography

    International Nuclear Information System (INIS)

    This introduction is addressed to an audience active in diverse forms of neutron source applications but not directly familiar with neutron radiography. Neutron radiography is, of course, similar to, and complementary to, radiography using x-rays. However, neutrons, being sensitive to the nuclear properties of materials, provide information fundamentally different from x-rays. For example, neutrons can penetrate many dense metals such as uranium, lead, bismuth or steel, and can reveal details of internal hydrogenous components: explosives, lubricants and gaskets. For nuclear fuel inspection neutron radiography offers the ability to penetrate dense uranium-238 and contrast the isotopes U-235 or Pu-239 and also offers the ability to discriminate against unwanted interference from gamma radiation. In addition to advantages in industrial applications, there are special situations in fields such as medical diagnostics, dentistry, agriculture and forensic science. Comprehensive accounts of applications in the field can be found in the proceedings of the world conferences on neutron radiography: USA (1981), FRANCE (1986). A third conference in this series is scheduled for May 1989 in Japan

  5. Improvement of Delayed Neutron Counting System

    Institute of Scientific and Technical Information of China (English)

    YUAN; Guo-jun; XIAO; Cai-jin; YANG; Wei; ZHANG; Gui-ying; JIN; Xiang-chun; WANG; Ping-sheng; NI; Bang-fa

    2012-01-01

    <正>A new delayed neutron counting system, which is good at qualitative and quantitative analysis of fissionable nuclide mixture, will be established at China Advanced Research Reactor (CARR). We use 3 He proportional counters to count the delayed neutrons after the samples irradiated by reactor neutrons, including U3O8-stantard, uranium ore and enriched uranium. Then, the counting efficiency and limit of this system were calculated.

  6. American Conference on Neutron Scattering 2014

    International Nuclear Information System (INIS)

    Scientists from the around the world converged in Knoxville, TN to have share ideas, present technical information and contribute to the advancement of neutron scattering. Featuring over 400 oral/poster presentations, ACNS 2014 offered a strong program of plenary, invited and contributed talks and poster sessions covering topics in soft condensed matter, hard condensed matter, biology, chemistry, energy and engineering applications in neutron physics - confirming the great diversity of science that is enabled by neutron scattering.

  7. American Conference on Neutron Scattering 2014

    Energy Technology Data Exchange (ETDEWEB)

    Dillen, J. Ardie [Materials Research Society, Warrendale, PA (United States)

    2014-12-31

    Scientists from the around the world converged in Knoxville, TN to have share ideas, present technical information and contribute to the advancement of neutron scattering. Featuring over 400 oral/poster presentations, ACNS 2014 offered a strong program of plenary, invited and contributed talks and poster sessions covering topics in soft condensed matter, hard condensed matter, biology, chemistry, energy and engineering applications in neutron physics – confirming the great diversity of science that is enabled by neutron scattering.

  8. MAGNETIC NEUTRON SCATTERING

    Energy Technology Data Exchange (ETDEWEB)

    ZALIZNYAK,I.A.; LEE,S.H.

    2004-07-30

    science, ranging from large-scale structures and dynamics of polymers and biological systems, to electronic properties of today's technological materials. Neutron scattering developed into a vast field, encompassing many different experimental techniques aimed at exploring different aspects of matter's atomic structure and dynamics. Modern magnetic neutron scattering includes several specialized techniques designed for specific studies and/or particular classes of materials. Among these are magnetic reflectometry aimed at investigating surfaces, interfaces, and multilayers, small-angle scattering for the large-scale structures, such as a vortex lattice in a superconductor, and neutron spin-echo spectroscopy for glasses and polymers. Each of these techniques and many others offer exciting opportunities for examining magnetism and warrant extensive reviews, but the aim of this chapter is not to survey how different neutron-scattering methods are used to examine magnetic properties of different materials. Here, we concentrate on reviewing the basics of the magnetic neutron scattering, and on the recent developments in applying one of the oldest methods, the triple axis spectroscopy, that still is among the most extensively used ones. The developments discussed here are new and have not been coherently reviewed. Chapter 2 of this book reviews magnetic small-angle scattering, and modern techniques of neutron magnetic reflectometry are discussed in Chapter 3.

  9. Neutron radiography

    International Nuclear Information System (INIS)

    The digital processing of the neutron radiography images gives the possibility for data quantification. In this case an exact relation between the measured neutron attenuation and the real macroscopic attenuation coefficient for every point of the sample is required. The assumption that the attenuation of the neutron beam through the sample is exponential is valid only in an ideal case where a monochromatic beam, non scattering sample and non background contribution are assumed. In the real case these conditions are not fulfilled and in dependence on the sample material we have more or less deviation from the exponential attenuation law. Because of the high scattering cross-sections of hydrogen (σs=80.26 barn) for thermal neutrons, the problem with the scattered neutrons at quantitative radiography investigations of hydrogenous materials (as PE, Oil, H2O, etc) is not trivial. For these strong scattering materials the neutron beam attenuation is no longer exponential and a dependence of the macroscopic attenuation coefficient on the material thickness and on the distance between the sample and the detector appears. When quantitative radiography (2 D) or tomography investigations (3 D) are performed, some image correction procedures for a description of the scattering effect are required. This thesis presents a method that can be used to enhance the neutron radiography image for objects with high scattering materials like hydrogen, carbon and other light materials. This method uses the Monte Carlo code, MCNP5, to simulate the neutron radiography process and get the flux distribution for each pixel of the image and determine the scattered neutrons distribution that causes the image blur and then subtract it from the initial image to improve its quality.

  10. Neutron tomography

    International Nuclear Information System (INIS)

    In this paper a survey is given of recent developments in selected areas of neutron tomography, within the context of several applications Argonne is involved in, including high penetration of reactor-fuel bundles in thick containers (involving TREAT and NRAD facilities), dual-energy hydrogen imaging (performed at IPNS), dynamic coarse-resolution emission tomography of rector fuel under test (a proposed modification to the TREAT hodoscope), and an associated-particle system that uses neutron flight-time to electronically collimate transmitted neutrons and to tomographically image nuclides identified by reaction gamma-rays

  11. Atmospheres around Neutron Stars

    Science.gov (United States)

    Fryer, Chris L.; Benz, Willy

    1994-12-01

    Interest in the behavior of atmospheres around neutron stars has grown astronomically in the past few years. Some of this interest arrived in the wake of the explosion of Supernova 1987A and its elusive remnant; spawning renewed interest in a method to insure material ``fall-back'' onto the adolescent neutron star in an effort to transform it into a silent black hole. However, the bulk of the activity with atmospheres around neutron stars is concentrated in stellar models with neutron star, rather than white dwarf, cores; otherwise known as Thorne-Zytkow objects. First a mere seed in the imagination of theorists, Thorne-Zytkow objects have grown into an observational reality with an ever-increasing list of formation scenarios and observational prospects. Unfortunately, the analytic work of Chevalier on supernova fall-back implies that, except for a few cases, the stellar simulations of Thorne-Zytkow objects are missing an important aspect of physics: neutrinos. Neutrino cooling removes the pressure support of these atmospheres, allowing accretion beyond the canonical Eddington rate for these objects. We present here the results of detailed hydrodynamical simulations in one and two dimensions with the additional physical effects of neutrinos, advanced equations of state, and relativity over a range of parameters for our atmosphere including entropy and chemical composition as well as a range in the neutron star size. In agreement with Chevalier, we find, under the current list of formation scenarios, that the creature envisioned by Thorne and Zytkow will not survive the enormous appetite of a neutron star. However, neutrino heating (a physical effect not considered in Chevalier's analysis) can play an important role in creating instabilities in some formation schemes, leading to an expulsion of matter rather than rapid accretion. By placing scrutiny upon the formation methods, we can determine the observational prospects for each.

  12. The ITER radial neutron camera: An updated neutronic analysis

    International Nuclear Information System (INIS)

    The radial neutron camera (RNC) will provide the spatial distribution and the total strength of the ITER neutron source (emissivity profile and fusion power) by means of collimated neutron measurements. Line-integrated neutron spectral measurements can also provide information on the ion temperature profile. The present design of the RNC consists of two collimating structures for a full coverage of the plasma: 36 collimated lines of sight (LOS) distributed in three different planes view the plasma core (ex-port system) and nine collimated LOS view the plasma edge (in-port system). The RNC design is based on the combined use of the MCNP Monte Carlo code and a software tool performing asymmetric Abel inversion of simulated measured neutron signals (MSST). Neutron and γ-ray transport calculations are performed with MCNP using a 3D RNC model to determine the signal/noise for each RNC channel and the spectra at the detectors. The MSST code is used to check the RNC compliance with the ITER measurement requirements for the neutron emissivity profile. In the present paper the improvement of the hard variance reduction technique applied to the MCNP neutron source (consisting in sampling neutrons only from plasma regions contributing to the detector signal) is presented and the following issues are analyzed: the possibility of reducing the length of the ex-port collimators (resulting in a significant reduction of the overall RNC dimension and weight); options for the reduction of the dose due to the neutron streaming through the RNC cut-outs in the blanket shielding module; the integration of a γ-ray detection system in the RNC by partially filling the collimators with a neutron absorbing material (LiH).

  13. Lightweight concrete with enhanced neutron shielding

    Energy Technology Data Exchange (ETDEWEB)

    Brindza, Paul Daniel; Metzger, Bert Clayton

    2016-09-13

    A lightweight concrete containing polyethylene terephthalate in an amount of 20% by total volume. The concrete is enriched with hydrogen and is therefore highly effective at thermalizing neutrons. The concrete can be used independently or as a component of an advanced neutron radiation shielding system.

  14. Peculiarities of the modern neutron spectrometry

    Indian Academy of Sciences (India)

    Yu P Popov

    2001-08-01

    Neutron spectrometry provides many branches of science and technology with the necessary data. Usually the main part of the data is supplied by powerful neutron time-of-flight spectrometers. Nevertheless there are many other very effective but simpler and cheaper neutron spectroscopy methods on accelerators, suitable for solution of plenty of scientific and applied problems (for example, in astrophysics and radioactive waste transmutation). The methods of slowing-down spectrometry in lead and graphite, generating of neutron spectra, characteristic for nucleosynthesis in the stars, and neutron spectrometry by means of primary -transition shift are discussed in the report.

  15. Statistical Uncertainty in Quantitative Neutron Radiography

    CERN Document Server

    Piegsa, Florian M

    2016-01-01

    We demonstrate a novel procedure to calibrate neutron detection systems commonly used in standard neutron radiography. This calibration allows determining the uncertainties due to Poisson-like neutron counting statistics for each individual pixel of a radiographic image. The obtained statistical errors are necessary in order to perform correct quantitative analysis. This fast and convenient method is applied to real data measured at the cold neutron radiography facility ICON at the Paul Scherrer Institute. Moreover, from the results the effective neutron flux at the beam line is determined.

  16. Neutron scattering

    International Nuclear Information System (INIS)

    This report contains the text of 16 lectures given at the Summer School and the report on a panel discussion entitled ''the relative merits and complementarities of x-rays, synchrotron radiation, steady- and pulsed neutron sources''. figs., tabs., refs

  17. Total cross sections for neutron-nucleus scattering

    OpenAIRE

    Suryanarayana, S. V.; H. Naik; Ganesan, S; Kailas, S; Choudhury, R. K.; Kim, Guinyum

    2010-01-01

    Systematics of neutron scattering cross sections on various materials for neutron energies up to several hundred MeV are important for ADSS applications. Ramsauer model is well known and widely applied to understand systematics of neutron nucleus total cross sections. In this work, we examined the role of nuclear effective radius parameter (r$_0$) on Ramsauer model fits of neutron total cross sections. We performed Ramsauer model global analysis of the experimental neutron total cross section...

  18. Neutron μstiX. Micrometer structure investigation with real space and reciprocal space crossover using neutron imaging detectors

    Energy Technology Data Exchange (ETDEWEB)

    Muehlbauer, Martin Johann

    2013-07-19

    This work is concerned with the investigation of inhomogeneities in materials with length scales of the order of micrometers by means of neutrons. In real space this is done by neutron imaging methods measuring the transmitted signal while for Ultra Small Angle Neutron Scattering (USANS) the signal of the scattered neutrons is assigned to a spatial frequency distribution in reciprocal space. The part about neutron imaging is focused on time-resolved neutron radiography on an injection nozzle similar to the ones used for modern diesel truck engines. The associated experiments have been carried out at the neutron imaging facility ANTARES at the Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) of the Technische Universitaet Muenchen in Garching near Munich. Especially the demands on the detector system were high. Therefore different detection methods and detector configurations have been tested. On the one hand the detector should allow for a time resolution high enough to record the injection process lasting about 900 μs. On the other hand it needed to offer a spatial resolution sufficient to resolve the test oil inside the spray hole of a maximum diameter of less than 200 μm. An advanced aim of this work is the visualization of cavitation phenomena which may occur during the injection process inside of the spray hole. In order to operate the injector at conditions as close to reality as possible a high pressure pump supplying the injector with test oil at a pressure of 1600 bar was needed in addition to the specially developed control electronics, the recuperation tank and the exhaust gas equipment for the escaping atomized spray. A second part of the work describes USANS experiments based on the idea of Dr. Roland Gaehler and carried out at the instrument D11 at the Institut Laue-Langevin in Grenoble. For this purpose a specific multi-beam geometry was applied, where a multi-slit aperture replaced the standard source aperture and the sample aperture was

  19. Neutron μstiX. Micrometer structure investigation with real space and reciprocal space crossover using neutron imaging detectors

    International Nuclear Information System (INIS)

    This work is concerned with the investigation of inhomogeneities in materials with length scales of the order of micrometers by means of neutrons. In real space this is done by neutron imaging methods measuring the transmitted signal while for Ultra Small Angle Neutron Scattering (USANS) the signal of the scattered neutrons is assigned to a spatial frequency distribution in reciprocal space. The part about neutron imaging is focused on time-resolved neutron radiography on an injection nozzle similar to the ones used for modern diesel truck engines. The associated experiments have been carried out at the neutron imaging facility ANTARES at the Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) of the Technische Universitaet Muenchen in Garching near Munich. Especially the demands on the detector system were high. Therefore different detection methods and detector configurations have been tested. On the one hand the detector should allow for a time resolution high enough to record the injection process lasting about 900 μs. On the other hand it needed to offer a spatial resolution sufficient to resolve the test oil inside the spray hole of a maximum diameter of less than 200 μm. An advanced aim of this work is the visualization of cavitation phenomena which may occur during the injection process inside of the spray hole. In order to operate the injector at conditions as close to reality as possible a high pressure pump supplying the injector with test oil at a pressure of 1600 bar was needed in addition to the specially developed control electronics, the recuperation tank and the exhaust gas equipment for the escaping atomized spray. A second part of the work describes USANS experiments based on the idea of Dr. Roland Gaehler and carried out at the instrument D11 at the Institut Laue-Langevin in Grenoble. For this purpose a specific multi-beam geometry was applied, where a multi-slit aperture replaced the standard source aperture and the sample aperture was

  20. 2010 Neutron Review: ORNL Neutron Sciences Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Bardoel, Agatha A [ORNL; Counce, Deborah M [ORNL; Ekkebus, Allen E [ORNL; Horak, Charlie M [ORNL; Nagler, Stephen E [ORNL; Kszos, Lynn A [ORNL

    2011-06-01

    During 2010, the Neutron Sciences Directorate focused on producing world-class science, while supporting the needs of the scientific community. As the instrument, sample environment, and data analysis tools at High Flux Isotope Reactor (HFIR ) and Spallation Neutron Source (SNS) have grown over the last year, so has promising neutron scattering research. This was an exciting year in science, technology, and operations. Some topics discussed are: (1) HFIR and SNS Experiments Take Gordon Battelle Awards for Scientific Discovery - Battelle Memorial Institute presented the inaugural Gordon Battelle Prizes for scientific discovery and technology impact in 2010. Battelle awards the prizes to recognize the most significant advancements at national laboratories that it manages or co-manages. (2) Discovery of Element 117 - As part of an international team of scientists from Russia and the United States, HFIR staff played a pivotal role in the discovery by generating the berkelium used to produce the new element. A total of six atoms of ''ununseptium'' were detected in a two-year campaign employing HFIR and the Radiochemical Engineering Development Center at Oak Ridge National Laboratory (ORNL) and the heavy-ion accelerator capabilities at the Joint Institute for Nuclear Research in Dubna, Russia. The discovery of the new element expands the understanding of the properties of nuclei at extreme numbers of protons and neutrons. The production of a new element and observation of 11 new heaviest isotopes demonstrate the increased stability of super-heavy elements with increasing neutron numbers and provide the strongest evidence to date for the existence of an island of enhanced stability for super-heavy elements. (3) Studies of Iron-Based High-Temperature Superconductors - ORNL applied its distinctive capabilities in neutron scattering, chemistry, physics, and computation to detailed studies of the magnetic excitations of iron-based superconductors (iron

  1. 2010 Neutron Review: ORNL Neutron Sciences Progress Report

    International Nuclear Information System (INIS)

    During 2010, the Neutron Sciences Directorate focused on producing world-class science, while supporting the needs of the scientific community. As the instrument, sample environment, and data analysis tools at High Flux Isotope Reactor (HFIR ) and Spallation Neutron Source (SNS) have grown over the last year, so has promising neutron scattering research. This was an exciting year in science, technology, and operations. Some topics discussed are: (1) HFIR and SNS Experiments Take Gordon Battelle Awards for Scientific Discovery - Battelle Memorial Institute presented the inaugural Gordon Battelle Prizes for scientific discovery and technology impact in 2010. Battelle awards the prizes to recognize the most significant advancements at national laboratories that it manages or co-manages. (2) Discovery of Element 117 - As part of an international team of scientists from Russia and the United States, HFIR staff played a pivotal role in the discovery by generating the berkelium used to produce the new element. A total of six atoms of ''ununseptium'' were detected in a two-year campaign employing HFIR and the Radiochemical Engineering Development Center at Oak Ridge National Laboratory (ORNL) and the heavy-ion accelerator capabilities at the Joint Institute for Nuclear Research in Dubna, Russia. The discovery of the new element expands the understanding of the properties of nuclei at extreme numbers of protons and neutrons. The production of a new element and observation of 11 new heaviest isotopes demonstrate the increased stability of super-heavy elements with increasing neutron numbers and provide the strongest evidence to date for the existence of an island of enhanced stability for super-heavy elements. (3) Studies of Iron-Based High-Temperature Superconductors - ORNL applied its distinctive capabilities in neutron scattering, chemistry, physics, and computation to detailed studies of the magnetic excitations of iron-based superconductors (iron pnictides and

  2. Piezonuclear Neutrons

    CERN Document Server

    Cardone, Fabio; Petrucci, Andrea

    2008-01-01

    We report the results of neutron measurements carried out during the application of ultrasounds to a solution containing only stable elements like Iron and Chlorine, without any other radioactive source of any kind. These measurements, carried out by CR39 detectors and a Boron TriFouride electronic detector, evidenced the emission of neutron pulses. These pulses stand well above the electronic noise and the background of the laboratory where the measurements were carried out.

  3. Introduction of Prompt Gamma Thermal Neutron Activation Analysis at CARR

    Institute of Scientific and Technical Information of China (English)

    WANG; Xing-hua; XIAO; Cai-jin; ZHANG; Gui-ying; YAO; Yong-gang; JIN; Xiang-chun; WANG; Ping-sheng; HUA; Long; NI; Bang-fa

    2013-01-01

    CARR will provide with maximal neutron flux in Asia,the third of the world.By using the high quality neutron beam and the advanced international experience,Prompt Gamma Neutron Activation Analysis(PGNAA)facility will be setup at high level.PGNAA on CARR will promote the development of nuclear analysis technology and improve Chinese status in the nuclear analysis field.

  4. Development calculational procedures for the neutron physics design of advanced pressurized water reactors (APWR) with tight triangular lattices in hexagonal fuel assemblies

    International Nuclear Information System (INIS)

    The new procedures for the calculation of infinite reactor zones build a synthesis of wellknown fast breeder (FBR) and light water reactor (LWR) methods. The data libraries are based on the 69 energy group structure of the WIMS code for thermal reactors and use the flexible storage mode of the FBR libraries. For the calculation of effective cross sections in the energy of neutron resonances, being very important in the APWR with its strongly epithermal neutron spectrum, several options are available. In most applications improved selfshielding tabulation formalisms (f-factor concept) are used. For more accurate investigations the fine flux programs ULFISP (own development) or RESABK (IKE, Stuttgart) may be selected. All cross section calculations use a modified version of the FBR code GRUCAL. Particularly the calculation of voided lattices may be improved at 69 groups with the program REMOCO or with a new 334 group library. The new calculational procedures could be qualified for a large number of LWR, APWR and FBR applications. The fuel assembly and whole core calculations are performed with available FBR methods. A new reactor core simulation program ARCOSI has been developed for the investigation of an APWR equilibrium core. The required cross sections come from fast interpolations of fuel assembly data on code-own libraries. The whole core calculations are performed with the fast nodal code HEXNODK, adopted from KWU. All calculational procedures are part of the powerful FBR code system KAPROS. (orig.)

  5. FOREWORD: Neutron metrology Neutron metrology

    Science.gov (United States)

    Thomas, David J.; Nolte, Ralf; Gressier, Vincent

    2011-12-01

    The International Committee for Weights and Measures (CIPM) has consultative committees covering various areas of metrology. The Consultative Committee for Ionizing Radiation (CCRI) differs from the others in having three sections: Section (I) deals with radiation dosimetry, Section (II) with radionuclide metrology and Section (III) with neutron metrology. In 2003 a proposal was made to publish special issues of Metrologia covering the work of the three Sections. Section (II) was the first to complete their task, and their special issue was published in 2007, volume 44(4). This was followed in 2009 by the special issue on radiation dosimetry, volume 46(2). The present issue, volume 48(6), completes the trilogy and attempts to explain neutron metrology, the youngest of the three disciplines, the neutron only having been discovered in 1932, to a wider audience and to highlight the relevance and importance of this field. When originally approached with the idea of this special issue, Section (III) immediately saw the value of a publication specifically on neutron metrology. It is a topic area where papers tend to be scattered throughout the literature in journals covering, for example, nuclear instrumentation, radiation protection or radiation measurements in general. Review articles tend to be few. People new to the field often ask for an introduction to the various topics. There are some excellent older textbooks, but these are now becoming obsolete. More experienced workers in specific areas of neutron metrology can find it difficult to know the latest position in related areas. The papers in this issue attempt, without presenting a purely historical outline, to describe the field in a sufficiently logical way to provide the novice with a clear introduction, while being sufficiently up-to-date to provide the more experienced reader with the latest scientific developments in the different topic areas. Neutron radiation fields obviously occur throughout the nuclear

  6. Advance Directives for End-of-Life Care and the Role of Health Education Specialists: Applying the Theory of Reasoned Action

    Science.gov (United States)

    Tremethick, Mary Jane; Johnson, Maureen K.; Carter, Mary R.

    2011-01-01

    Quality end-of-life care is subjective and based on individual values and beliefs. An advance directive provides a legal means of communicating these values and beliefs, as well as preferences in regards to end-of-life care when an individual is no longer able to make his or her desires known. In many nations, advance directives are underused…

  7. Controlling neutron orbital angular momentum.

    Science.gov (United States)

    Clark, Charles W; Barankov, Roman; Huber, Michael G; Arif, Muhammad; Cory, David G; Pushin, Dmitry A

    2015-09-24

    The quantized orbital angular momentum (OAM) of photons offers an additional degree of freedom and topological protection from noise. Photonic OAM states have therefore been exploited in various applications ranging from studies of quantum entanglement and quantum information science to imaging. The OAM states of electron beams have been shown to be similarly useful, for example in rotating nanoparticles and determining the chirality of crystals. However, although neutrons--as massive, penetrating and neutral particles--are important in materials characterization, quantum information and studies of the foundations of quantum mechanics, OAM control of neutrons has yet to be achieved. Here, we demonstrate OAM control of neutrons using macroscopic spiral phase plates that apply a 'twist' to an input neutron beam. The twisted neutron beams are analysed with neutron interferometry. Our techniques, applied to spatially incoherent beams, demonstrate both the addition of quantum angular momenta along the direction of propagation, effected by multiple spiral phase plates, and the conservation of topological charge with respect to uniform phase fluctuations. Neutron-based studies of quantum information science, the foundations of quantum mechanics, and scattering and imaging of magnetic, superconducting and chiral materials have until now been limited to three degrees of freedom: spin, path and energy. The optimization of OAM control, leading to well defined values of OAM, would provide an additional quantized degree of freedom for such studies. PMID:26399831

  8. Fast-Neutron Surveys Using Indium-Foil Activation

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, Lloyd D.; Smith, Alan R.

    1958-08-13

    Activation of indium foils by thermal neutrons has been applied to measurement of fast-neutron fluxes. Foils are encased in paraffin spheres placed in cadmium boxes. The high-energy neutrons that penetrate the cadmium become thermal neutrons; the thermal-neutron flux is proportional to the incident fast-neutron flux over a range of about 20 kev to 20 Mev. The foils are removed from the boxes and counted on a methane-flow proportional counter. High instantaneous neutron fluxes are easily detected and counted by use of these foils. Many simultaneous measurements have been made easily by this method.

  9. Neutron scattering science in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Knott, Robert [Australian Nuclear Science and Technology Organisation, Menai, NSW (Australia)

    1999-10-01

    Neutron scattering science in Australia is making an impact on a number of fields in the scientific and industrial research communities. The unique properties of the neutron are being used to investigate problems in chemistry, materials science, physics, engineering and biology. The reactor HIFAR at the Australian Nuclear Science and Technology Organisation research laboratories is the only neutron source in Australia suitable for neutron scattering science. A suite of instruments provides a wide range of opportunities for the neutron scattering community that extends throughout universities, government and industrial research laboratories. Plans are in progress to replace the present research reactor with a modern multi-purpose research reactor to offer the most advanced neutron scattering facilities. The experimental and analysis equipment associated with a modern research reactor will permit the establishment of a national centre for world class neutron science research focussed on the structure and functioning of materials, industrial irradiations and analyses in support of Australian manufacturing, minerals, petrochemical, pharmaceuticals and information science industries. (author)

  10. Neutron science opportunities at pulsed spallation neutron sources

    International Nuclear Information System (INIS)

    Using the IPNS Upgrade plan developed at Argonne National Laboratory as a worked example of the design of a pulsed spallation neutron source, this paper explores some of the scientific applications of an advanced facility for materials science studies and the instrumentation for those purposes

  11. Cherenkov neutron detector for fusion reaction and runaway electron diagnostics

    International Nuclear Information System (INIS)

    A Cherenkov-type neutron detector was newly developed and neutron measurement experiments were performed at Korea Superconducting Tokamak Advanced Research. It was shown that the Cherenkov neutron detector can monitor the time-resolved neutron flux from deuterium-fueled fusion plasmas. Owing to the high temporal resolution of the detector, fast behaviors of runaway electrons, such as the neutron spikes, could be observed clearly. It is expected that the Cherenkov neutron detector could be utilized to provide useful information on runaway electrons as well as fusion reaction rate in fusion plasmas

  12. Sensitivity of the neutron crystal diffraction experiment to the neutron EDM and to the nuclear P-,T-violating forces

    OpenAIRE

    Baryshevsky, V. G.; Cherkas, S. L.

    2007-01-01

    We establish a link between an angle of the neutron polarization rotation in a crystal diffraction experiment and constants of the P-,T- violating interactions. The consideration applies to the energy range of thermal and resonance neutrons.

  13. An overview on the advanced oxidation processes applied for the treatment of water pollutants defined in the recently launched Directive 2013/39/EU.

    Science.gov (United States)

    Ribeiro, Ana R; Nunes, Olga C; Pereira, Manuel F R; Silva, Adrián M T

    2015-02-01

    Environmental pollution is a recognized issue of major concern since a wide range of contaminants has been found in aquatic environment at ngL(-1) to μgL(-1) levels. In the year 2000, a strategy was defined to identify the priority substances concerning aquatic ecosystems, followed by the definition of environmental quality standards (EQS) in 2008. Recently it was launched the Directive 2013/39/EU that updates the water framework policy highlighting the need to develop new water treatment technologies to deal with such problem. This review summarizes the data published in the last decade regarding the application of advanced oxidation processes (AOPs) to treat priority compounds and certain other pollutants defined in this Directive, excluding the inorganic species (cadmium, lead, mercury, nickel and their derivatives). The Directive 2013/39/EU includes several pesticides (aldrin, dichlorodiphenyltrichloroethane, dicofol, dieldrin, endrin, endosulfan, isodrin, heptachlor, lindane, pentachlorophenol, chlorpyrifos, chlorfenvinphos, dichlorvos, atrazine, simazine, terbutryn, diuron, isoproturon, trifluralin, cypermethrin, alachlor), solvents (dichloromethane, dichloroethane, trichloromethane and carbon tetrachloride), perfluorooctane sulfonic acid and its derivatives (PFOS), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), nonylphenol and octylphenol, as well as the three compounds included in the recommendation for the first watch list of substances (diclofenac, 17-alpha-ethinylestradiol (EE2) and 17-beta-estradiol (E2)). Some particular pesticides (aclonifen, bifenox, cybutryne, quinoxyfen), organotin compounds (tributyltin), dioxins and dioxin-like compounds, brominated diphenylethers, hexabromocyclododecanes and di(2-ethylhexyl)phthalate are also defined in this Directive, but studies dealing with AOPs are missing. AOPs are recognized tools to destroy recalcitrant compounds or, at least, to transform them into biodegradable species

  14. Neutron Repulsion

    CERN Document Server

    Manuel, Oliver K

    2011-01-01

    Earth is connected gravitationally, magnetically and electrically to its heat source - a neutron star that is obscured from view by waste products in the photosphere. Neutron repulsion is like the hot filament in an incandescent light bulb. Excited neutrons are emitted from the solar core and decay into hydrogen that glows in the photosphere like a frosted light bulb. Neutron repulsion was recognized in nuclear rest mass data in 2000 as the overlooked source of energy, the keystone of an arch that locked together these puzzling space-age observations: 1.) Excess 136Xe accompanied primordial helium in the stellar debris that formed the solar system (Fig. 1); 2.) The Sun formed on the supernova core (Fig. 2); 3.) Waste products from the core pass through an iron-rich mantle, selectively carrying lighter elements and lighter isotopes of each element into the photosphere (Figs. 3-4); and 4.) Neutron repulsion powers the Sun and sustains life (Figs. 5-7). Together these findings offer a framework for understanding...

  15. Functional renormalization group studies of nuclear and neutron matter

    CERN Document Server

    Drews, Matthias

    2016-01-01

    Functional renormalization group (FRG) methods applied to calculations of isospin-symmetric and asymmetric nuclear matter as well as neutron matter are reviewed. The approach is based on a chiral Lagrangian expressed in terms of nucleon and meson degrees of freedom as appropriate for the hadronic phase of QCD with spontaneously broken chiral symmetry. Fluctuations beyond mean-field approximation are treated solving Wetterich's FRG flow equations. Nuclear thermodynamics and the nuclear liquid-gas phase transition are investigated in detail, both in symmetric matter and as a function of the proton fraction in asymmetric matter. The equations of state at zero temperature of symmetric nuclear matter and pure neutron matter are found to be in good agreement with advanced ab-initio many-body computations. Contacts with perturbative many-body approaches (in-medium chiral perturbation theory) are discussed. As an interesting test case, the density dependence of the pion mass in the medium is investigated. The questio...

  16. Personnel neutron dosimetry at Department of Energy facilities

    Energy Technology Data Exchange (ETDEWEB)

    Brackenbush, L.W.; Endres, G.W.R.; Selby, J.M.; Vallario, E.J.

    1980-08-01

    This study assesses the state of personnel neutron dosimetry at DOE facilities. A survey of the personnel dosimetry systems in use at major DOE facilities was conducted, a literature search was made to determine recent advances in neutron dosimetry, and several dosimetry experts were interviewed. It was concluded that personnel neutron dosimeters do not meet current needs and that serious problems exist now and will increase in the future if neutron quality factors are increased and/or dose limits are lowered.

  17. Personnel neutron dosimetry at Department of Energy facilities

    International Nuclear Information System (INIS)

    This study assesses the state of personnel neutron dosimetry at DOE facilities. A survey of the personnel dosimetry systems in use at major DOE facilities was conducted, a literature search was made to determine recent advances in neutron dosimetry, and several dosimetry experts were interviewed. It was concluded that personnel neutron dosimeters do not meet current needs and that serious problems exist now and will increase in the future if neutron quality factors are increased and/or dose limits are lowered

  18. Spectral unfolding of fast neutron energy distributions

    Science.gov (United States)

    Mosby, Michelle; Jackman, Kevin; Engle, Jonathan

    2015-10-01

    The characterization of the energy distribution of a neutron flux is difficult in experiments with constrained geometry where techniques such as time of flight cannot be used to resolve the distribution. The measurement of neutron fluxes in reactors, which often present similar challenges, has been accomplished using radioactivation foils as an indirect probe. Spectral unfolding codes use statistical methods to adjust MCNP predictions of neutron energy distributions using quantified radioactive residuals produced in these foils. We have applied a modification of this established neutron flux characterization technique to experimentally characterize the neutron flux in the critical assemblies at the Nevada National Security Site (NNSS) and the spallation neutron flux at the Isotope Production Facility (IPF) at Los Alamos National Laboratory (LANL). Results of the unfolding procedure are presented and compared with a priori MCNP predictions, and the implications for measurements using the neutron fluxes at these facilities are discussed.

  19. Material examination by neutron radiography

    International Nuclear Information System (INIS)

    Neutron radiography as a non-destructive testing technique has played a prominent role in the development of fuel for research and power reactors; studying of dimensional changes due to irradiation; inspection of corrosion in airframe structures and propeller blades; detection of light components and materials in explosive an investigation of diffusion of water into building materials etc. The development of neutron radiography facility by extracting a beam of thermal neutrons through a radial beam port around the Pakistan Research Reactor-1 is described. Graphite block of 30 cm thickness and bismuth block of 25 cm thickness have been used to boost-up thermal neutrons flux level and filter out high energy gamma radiation from the beam respectively. Thermal neutron flux level of the order of 1.06x10/sup 6/ n.cm/sup -2/. s/sup -1/ and a neutron to gamma ratio of the order of 10/sup 5/ n.cm/sup -2/.mR/sup -1/ have been measured at the object position which make the facility useful for investigation of material characteristics an properties applying direct neutron radiography method. The facility has been subjected to modifications and changes in order to enhance thermal neutron flux level and reduce the exposure time for better image quality at the object position. The use of beam purity and sensitivity indicators for determining the beam constituents and resolution of the technique is discussed. Visibility of holes under the lead and acrylic step wedges categorize the facility for direct applications. Neutron cross-sections for different metallic as well as composite materials have been determined by applying neutron radiographic technique. The use of neutron radiography as a complimentary technique to ensure the quality of nuclear fuel in addition to other applications like detection of light components in explosives and pyrotechnic devices is investigated. Detection of corrosion in aluminum joints, deformation in aeronautical components and honeycomb structures is

  20. Development of fast neutron radiography system based on portable neutron generator

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Chia Jia, E-mail: gei-i-kani@hotmail.com; Nilsuwankosit, Sunchai, E-mail: sunchai.n@chula.ac.th [Department of Nuclear Engineering, Faculty of Engineering, Chulalongkorn University, Phayathai Rd., Patumwan, Bangkok, THAILAND 10330 (Thailand)

    2016-01-22

    Due to the high installation cost, the safety concern and the immobility of the research reactors, the neutron radiography system based on portable neutron generator is proposed. Since the neutrons generated from a portable neutron generator are mostly the fast neutrons, the system is emphasized on using the fast neutrons for the purpose of conducting the radiography. In order to suppress the influence of X-ray produced by the neutron generator, a combination of a shielding material sandwiched between two identical imaging plates is used. A binary XOR operation is then applied for combining the information from the imaging plates. The raw images obtained confirm that the X-ray really has a large effect and that XOR operation can help enhance the effect of the neutrons.

  1. Development of fast neutron radiography system based on portable neutron generator

    Science.gov (United States)

    Yi, Chia Jia; Nilsuwankosit, Sunchai

    2016-01-01

    Due to the high installation cost, the safety concern and the immobility of the research reactors, the neutron radiography system based on portable neutron generator is proposed. Since the neutrons generated from a portable neutron generator are mostly the fast neutrons, the system is emphasized on using the fast neutrons for the purpose of conducting the radiography. In order to suppress the influence of X-ray produced by the neutron generator, a combination of a shielding material sandwiched between two identical imaging plates is used. A binary XOR operation is then applied for combining the information from the imaging plates. The raw images obtained confirm that the X-ray really has a large effect and that XOR operation can help enhance the effect of the neutrons.

  2. Development of fast neutron radiography system based on portable neutron generator

    International Nuclear Information System (INIS)

    Due to the high installation cost, the safety concern and the immobility of the research reactors, the neutron radiography system based on portable neutron generator is proposed. Since the neutrons generated from a portable neutron generator are mostly the fast neutrons, the system is emphasized on using the fast neutrons for the purpose of conducting the radiography. In order to suppress the influence of X-ray produced by the neutron generator, a combination of a shielding material sandwiched between two identical imaging plates is used. A binary XOR operation is then applied for combining the information from the imaging plates. The raw images obtained confirm that the X-ray really has a large effect and that XOR operation can help enhance the effect of the neutrons

  3. An improved method for estimating the neutron background in measurements of neutron capture reactions

    Science.gov (United States)

    Žugec, P.; Bosnar, D.; Colonna, N.; Gunsing, F.

    2016-08-01

    The relation between the neutron background in neutron capture measurements and the neutron sensitivity related to the experimental setup is examined. It is pointed out that a proper estimate of the neutron background may only be obtained by means of dedicated simulations taking into account the full framework of the neutron-induced reactions and their complete temporal evolution. No other presently available method seems to provide reliable results, in particular under the capture resonances. An improved neutron background estimation technique is proposed, the main improvement regarding the treatment of the neutron sensitivity, taking into account the temporal evolution of the neutron-induced reactions. The technique is complemented by an advanced data analysis procedure based on relativistic kinematics of neutron scattering. The analysis procedure allows for the calculation of the neutron background in capture measurements, without requiring the time-consuming simulations to be adapted to each particular sample. A suggestion is made on how to improve the neutron background estimates if neutron background simulations are not available.

  4. Investigation of fuel cells using scanning neutron imaging and a focusing neutron guide

    International Nuclear Information System (INIS)

    We present two different methods to increase the size of available neutron beams in order to allow for the investigation of large objects. Application of these methods is demonstrated for radiographic imaging of fuel cells. The first approach is a scanning procedure based on the coordinated translation of detector and sample through the beam. Further advancement was achieved by installing a focusing neutron guide, which offers an expanded neutron beam size after diverging from a focused point source.

  5. The behavior of neutron emissions during ICRF minority heating of plasma at EAST

    Science.gov (United States)

    Zhong, Guoqiang; Cao, Hongrui; Hu, Liqun; Zhou, Ruijie; Xiao, Min; Li, Kai; Pu, Neng; Huang, Juan; Liu, Guangzhu; Lin, Shiyao; Lyu, Bo; Liu, Haiqing; Zhang, Xinjun; EAST Team

    2016-07-01

    Ion cyclotron radio frequency (ICRF) wave heating is a primary method to heat ions in the Experimental Advanced Superconducting Tokamak (EAST). Through neutron diagnostics, effective ion heating was observed in hydrogenminority heating (MH) scenarios. At present, investigation of deuterium-deuterium (DD) fusion neutrons is mostly based on time-resolved flux monitor and spectrometer measurements. When the ICRF was applied, the neutron intensity became one order higher. The H/H  +  D ratio was in the range of 5-10%, corresponding to the hydrogen MH dominated scenario, and a strong high energy tail was not displayed on the neutron spectrum that was measured by a liquid scintillator. Moreover, ion temperature in the plasma center (T i) was inversely calculated by the use of neutron source strength (S n) and the plasma density based on classical fusion reaction equations. This result indicates that T i increases by approximately 30% in L-mode plasma, and by more than 50% in H-mode plasma during ICRF heating, which shows good agreement with x-ray crystal spectrometer (XCS) diagnostics. Finally, the DD neutron source strength scaling law, with regard to plasma current (I P) and ICRF coupling power (P RF) on the typical minority heating condition, was obtained by statistical analysis.

  6. neutron radiography

    International Nuclear Information System (INIS)

    Neutron radiography (or radiology) is a diverse filed that uses neutrons of various energies, subthermal, thermal, epithermal or fast in either steady state or pulsed mode to examine objects for industrial, medical, or other purposes, both microscopic and macroscopic. The applications include engineering design, biological studies, nondestructive inspection and materials evaluation. In the past decade, over 100 different centers in some 30 countries have published reports of pioneering activities using reactors, accelerators and isotopic neutron sources. While film transparency and electronic video are most common imaging methods for static or in motion objects respectively, there are other important data gathering techniques, including track etch, digital gauging and computed tomography. A survey of the world-wide progress shows the field to be gaining steadily in its diversity, its sophistication and its importance. (author)

  7. Thermalization of monoenergetic neutrons in a concrete room

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H.R.; Manzanares A, E.; Hernandez D, V.M.; Mercado, G.A. [UAZ, A.P. 336, 98000 Zacatecas (Mexico); Iniguez, M.P.; Martin M, A. [Universidad de Valladolid, (Spain)

    2006-07-01

    The thermalization of neutrons from monoenergetic neutron sources in a concrete room has been studied. During calibration of neutron detectors it is mandatory to make corrections due to neutron scattering produced by the room walls, therefore this factor must be known in advance. The scattered neutrons are thermalized and produce a neutron field that is directly proportional to source strength and inversely proportional to room total wall-surfaces, the proportional coefficient has been calculated for neutrons whose energy goes from 1 eV to 20 MeV. This coefficient was calculated using Monte Carlo methods for 150, 200 and 300 cm-radius spherical cavity, where monoenergetic neutrons were located at the center, along the spherical cavity radius neutron spectra were calculated at several source-to-detector distances inside the cavity. The obtained coefficient is almost three times larger than the factor normally utilized. (Author)

  8. Development of a bandwidth limiting neutron chopper for CSNS

    Energy Technology Data Exchange (ETDEWEB)

    Wang, P., E-mail: wangping@ihep.ac.cn [China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences - CAS, Dongguan 523803 (China); Dongguan Institute of Neutron Science (DINS), Dongguan 523808 (China); Yang, B.; Cai, W.L. [China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences - CAS, Dongguan 523803 (China); Dongguan Institute of Neutron Science (DINS), Dongguan 523808 (China)

    2015-08-21

    Bandwidth limiting neutron choppers are indispensable key equipments for the time-of-flight neutron scattering spectrometers of China Spallation Neutron Source (CSNS). The main principle is to chop the neutron beam to limit the neutron wavelength bandwidth at the neutron detector. We have successfully developed a bandwidth limiting neutron chopper for CSNS in the CSNS advance research project II. The transmission rate of the neutron absorbing coating is less than 1×10{sup −4} (for 1 angstrom neutron). The phase control accuracy is ±0.084° (±9.4 μs at 25 Hz). The dynamic balance grade is G1.0. Various experimental technical features have met the design requirements, and it also runs stably and reliably during the long-term tests.

  9. Neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Heger, G. [Rheinisch-Westfaelische Technische Hochschule Aachen, Inst. fuer Kristallographie, Aachen (Germany)

    1996-12-31

    X-ray diffraction using conventional laboratory equipment and/or synchrotron installations is the most important method for structure analyses. The purpose of this paper is to discuss special cases, for which, in addition to this indispensable part, neutrons are required to solve structural problems. Even though the huge intensity of modern synchrotron sources allows in principle the study of magnetic X-ray scattering the investigation of magnetic structures is still one of the most important applications of neutron diffraction. (author) 15 figs., 1 tab., 10 refs.

  10. Neutron scattering techniques for betaine calcium chloride dihydrate under applied external field (temperature, electric field and hydrostatic pressure); Etude par diffusion de neutrons du chlorure de calcium et de betaine dihydrate sous champ externe applique (temperature, champ electrique et pression hydrostatique)

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, O

    1997-11-17

    We have studied with neutron scattering techniques betaine calcium chloride dihydrate (BCCD), a dielectric aperiodic crystal which displays a Devil`s staircase type phase diagram made up of several incommensurate and commensurate phases, having a range of stability very sensitive to temperature, electric field and hydrostatic pressure. We have measured a global hysteresis of {delta}(T) of about 2-3 K in the two incommensurate phases. A structural study of the modulated commensurate phases 1/4 and 1/5 allows us to evidence that the atomic modulation functions are anharmonic. The relevance of the modelization of the modulated structure by polar Ising pseudo-spins is then directly established. On the basis of group theory calculation in the four dimensional super-space, we interpret this anharmonic modulation as a soliton regime with respect to the lowest-temperature non modulated ferroelectric phase. The continuous character of the transition to the lowest-temperature non modulated phase and the diffuse scattering observed in this phase are accounted for the presence of ferroelectric domains separated by discommensurations. Furthermore, we have shown that X-rays induce in BCCD a strong variation with time of irradiation of the intensity of satellite peaks, and more specifically for third order ones. This is why the `X-rays` structural model is found more harmonic than the `neutron` one. Under electric field applied along the vector b axis, we confirm that commensurate phases with {delta} = even/odd are favoured and hence are polar along this direction. We have evidenced at 10 kV / cm two new higher order commensurate phases in the phase INC2, corroborating the idea of a `complete` Devil`s air-case phase diagram. A phenomenon of generalized coexistence of phases occurs above 5 kV / cm. We have characterized at high field phase transitions between `coexisting` phases, which are distinguishable from classical lock-in transitions. Under hydrostatic pressure, our results

  11. Neutron protein crystallography

    Energy Technology Data Exchange (ETDEWEB)

    Niimura, Nobuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-10-01

    X-ray diffraction of single crystal has enriched the knowledge of various biological molecules such as proteins, DNA, t-RNA, viruses, etc. It is difficult to make structural analysis of hydrogen atoms in a protein using X-ray crystallography, whereas neutron diffraction seems usable to directly determine the location of those hydrogen atoms. Here, neutron diffraction method was applied to structural analysis of hen egg-white lysozyme. Since the crystal size of a protein to analyze is generally small (5 mm{sup 3} at most), the neutron beam at the sample position in monochromator system was set to less than 5 x 5 mm{sup 2} and beam divergence to 0.4 degree or less. Neutron imaging plate with {sup 6}Li or Gd mixed with photostimulated luminescence material was used and about 2500 Bragg reflections were recorded in one crystal setting. A total of 38278 reflections for 2.0 A resolution were collected in less than 10 days. Thus, stereo views of Trp-111 omit map around the indol ring of Trp-111 was presented and the three-dimensional arrangement of 696H and 264D atoms in the lysozyme molecules was determined using the omit map. (M.N.)

  12. Fast-neutron interaction with niobium

    International Nuclear Information System (INIS)

    Results of a comprehensive study of the interaction of fast neutrons with niobium are presented, including measurement and interpretation of neutron total, differential-scattering and radiative-capture cross sections. The experimental results are interpreted in the context of the optical-statistical model, with attention to the Fermi-surface anomaly. Experimental results, physical interpretations and rigorous statistical methods are used to provide a comprehensive evaluated nuclear data file suitable for use in a wide range of applied neutronic calculations

  13. A compound parabolic concentrator as an ultracold neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Hickerson, K.P., E-mail: hickerson@gmail.com; Filippone, B.W., E-mail: bradf@caltech.edu

    2013-09-01

    The design principles of nonimaging optics are applied to ultracold neutrons (UCN). In particular a vertical compound parabolic concentrator (CPC) that efficiently redirects UCN vertically into a bounded spatial volume where they have a maximum energy mga that depends only on the initial phase space cross sectional area πa{sup 2} creates a spectrometer which can be applied to neutron lifetime and gravitational quantum state experiments. -- Highlights: • Nonimaging optics is applied to ultracold neutrons. • A novel ultracold neutron spectrometer is discussed. • New uses may include a neutron lifetime experiment.

  14. German neutron scattering conference. Programme and abstracts

    International Nuclear Information System (INIS)

    The German Neutron Scattering Conference 2012 - Deutsche Neutronenstreutagung DN 2012 offers a forum for the presentation and critical discussion of recent results obtained with neutron scattering and complementary techniques. The meeting is organized on behalf of the German Committee for Research with Neutrons - Komitee Forschung mit Neutronen KFN - by the Juelich Centre for Neutron Science JCNS of Forschungszentrum Juelich GmbH. In between the large European and international neutron scattering conferences ECNS (2011 in Prague) and ICNS (2013 in Edinburgh), it offers the vibrant German and international neutron community an opportunity to debate topical issues in a stimulating atmosphere. Originating from ''BMBF Verbundtreffen'' - meetings for projects funded by the German Federal Ministry of Education and Research - this conference series has a strong tradition of providing a forum for the discussion of collaborative research projects and future developments in the field of research with neutrons in general. Neutron scattering, by its very nature, is used as a powerful probe in many different disciplines and areas, from particle and condensed matter physics through to chemistry, biology, materials sciences, engineering sciences, right up to geology and cultural heritage; the German Neutron Scattering Conference thus provides a unique chance for exploring interdisciplinary research opportunities. It also serves as a showcase for recent method and instrument developments and to inform users of new advances at neutron facilities.

  15. German neutron scattering conference. Programme and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas (ed.)

    2012-07-01

    The German Neutron Scattering Conference 2012 - Deutsche Neutronenstreutagung DN 2012 offers a forum for the presentation and critical discussion of recent results obtained with neutron scattering and complementary techniques. The meeting is organized on behalf of the German Committee for Research with Neutrons - Komitee Forschung mit Neutronen KFN - by the Juelich Centre for Neutron Science JCNS of Forschungszentrum Juelich GmbH. In between the large European and international neutron scattering conferences ECNS (2011 in Prague) and ICNS (2013 in Edinburgh), it offers the vibrant German and international neutron community an opportunity to debate topical issues in a stimulating atmosphere. Originating from ''BMBF Verbundtreffen'' - meetings for projects funded by the German Federal Ministry of Education and Research - this conference series has a strong tradition of providing a forum for the discussion of collaborative research projects and future developments in the field of research with neutrons in general. Neutron scattering, by its very nature, is used as a powerful probe in many different disciplines and areas, from particle and condensed matter physics through to chemistry, biology, materials sciences, engineering sciences, right up to geology and cultural heritage; the German Neutron Scattering Conference thus provides a unique chance for exploring interdisciplinary research opportunities. It also serves as a showcase for recent method and instrument developments and to inform users of new advances at neutron facilities.

  16. KSTAR Application for Fast Neutron Radiography

    International Nuclear Information System (INIS)

    Korea Superconducting Tokamak Advanced Research (KSTAR) is a magnetic fusion device being built at the National Fusion Research Institute in Daejon, Korea. After the successful first operation in 2008, the plasma performance is enhanced and duration of H-mode is extended to around 50 sec. In addition to long-pulse operation, the operational boundary of the H-mode discharge is extended over MHD no-wall limit. The basic design of the setup, based on the typical configuration, was decided for the first step of the experiments. Several type of scintillator is being ready to be examined for the best performance. The first setup will be applied in KSTAR 2015 campaign, and it can characterize the neutron radiation from KSTAR. Based on the data, the optimum design of the setup for fast radiography can be derived

  17. Introduction to special section of the Journal of Family Psychology, advances in mixed methods in family psychology: integrative and applied solutions for family science.

    Science.gov (United States)

    Weisner, Thomas S; Fiese, Barbara H

    2011-12-01

    Mixed methods in family psychology refer to the systematic integration of qualitative and quantitative techniques to represent family processes and settings. Over the past decade, significant advances have been made in study design, analytic strategies, and technological support (such as software) that allow for the integration of quantitative and qualitative methods and for making appropriate inferences from mixed methods. This special section of the Journal of Family Psychology illustrates how mixed methods may be used to advance knowledge in family science through identifying important cultural differences in family structure, beliefs, and practices, and revealing patterns of family relationships to generate new measurement paradigms and inform clinical practice. Guidance is offered to advance mixed methods research in family psychology through sound principles of peer review.

  18. ANSL-V: ENDF/B-V based multigroup cross-section libraries for Advanced Neutron Source (ANS) reactor studies. Supplement 1

    International Nuclear Information System (INIS)

    The original ANSL-V cross-section libraries (ORNL-6618) were developed over a period of several years for the physics analysis of the ANS reactor, with little thought toward including the materials commonly needed for shielding applications. Materials commonly used for shielding applications include calcium barium, sulfur, phosphorous, and bismuth. These materials, as well as 6Li, 7Li, and the naturally occurring isotopes of hafnium, have been added to the ANSL-V libraries. The gamma-ray production and gamma-ray interaction cross sections were completely regenerated for the ANSL-V 99n/44g library which did not exist previously. The MALOCS module was used to collapse the 99n/44g coupled library to the 39n/44g broad- group library. COMET was used to renormalize the two-dimensional (2- D) neutron matrix sums to agree with the one-dimensional (1-D) averaged values. The FRESH module was used to adjust the thermal scattering matrices on the 99n/44g and 39n/44g ANSL-V libraries. PERFUME was used to correct the original XLACS Legendre polynomial fits to produce acceptable distributions. The final ANSL-V 99n/44g and 39n/44g cross-section libraries were both checked by running RADE. The AIM module was used to convert the master cross-section libraries from binary coded decimal to binary format (or vice versa)

  19. ANSL-V: ENDF/B-V based multigroup cross-section libraries for Advanced Neutron Source (ANS) reactor studies. Supplement 1

    Energy Technology Data Exchange (ETDEWEB)

    Wright, R.Q.; Renier, J.P.; Bucholz, J.A.

    1995-08-01

    The original ANSL-V cross-section libraries (ORNL-6618) were developed over a period of several years for the physics analysis of the ANS reactor, with little thought toward including the materials commonly needed for shielding applications. Materials commonly used for shielding applications include calcium barium, sulfur, phosphorous, and bismuth. These materials, as well as {sup 6}Li, {sup 7}Li, and the naturally occurring isotopes of hafnium, have been added to the ANSL-V libraries. The gamma-ray production and gamma-ray interaction cross sections were completely regenerated for the ANSL-V 99n/44g library which did not exist previously. The MALOCS module was used to collapse the 99n/44g coupled library to the 39n/44g broad- group library. COMET was used to renormalize the two-dimensional (2- D) neutron matrix sums to agree with the one-dimensional (1-D) averaged values. The FRESH module was used to adjust the thermal scattering matrices on the 99n/44g and 39n/44g ANSL-V libraries. PERFUME was used to correct the original XLACS Legendre polynomial fits to produce acceptable distributions. The final ANSL-V 99n/44g and 39n/44g cross-section libraries were both checked by running RADE. The AIM module was used to convert the master cross-section libraries from binary coded decimal to binary format (or vice versa).

  20. Self-shielding effects in neutron spectra measurements for neutron capture therapy by means of activation foils.

    Science.gov (United States)

    Pytel, Krzysztof; Józefowicz, Krystyna; Pytel, Beatrycze; Koziel, Alina

    2004-01-01

    The design and optimisation of a neutron beam for neutron capture therapy (NCT) is accompanied by the neutron spectra measurements at the target position. The method of activation detectors was applied for the neutron spectra measurements. Epithermal neutron energy region imposes the resonance structure of activation cross sections resulting in strong self-shielding effects. The neutron self-shielding correction factor was calculated using a simple analytical model of a single absorption event. Such a procedure has been applied to individual cross sections from pointwise ENDF/B-VI library and new corrected activation cross sections were introduced to a spectra unfolding algorithm. The method has been verified experimentally both for isotropic and for parallel neutron beams. Two sets of diluted and non-diluted activation foils covered with cadmium were irradiated in the neutron field. The comparison of activation rates of diluted and non-diluted foils has demonstrated the correctness of the applied self-shielding model.

  1. On scaling and optimization of high-intensity, low-beam-loss RF linacs for neutron source drivers

    International Nuclear Information System (INIS)

    RF linacs providing cw proton beams of 30--250 mA at 800--1600 MeV, and cw deuteron beams of 100--250 mA at 35--40 MeV, are needed as drivers for factory neutron sources applied to radioactive waste transmutation, advanced energy production, materials testing facilities, and spallation neutron sources. The maintenance goals require very low beam loss along the linac. Optimization of such systems is complex; status of beam dynamics aspects presently being investigated is outlined

  2. Methods for absorbing neutrons

    Science.gov (United States)

    Guillen, Donna P.; Longhurst, Glen R.; Porter, Douglas L.; Parry, James R.

    2012-07-24

    A conduction cooled neutron absorber may include a metal matrix composite that comprises a metal having a thermal neutron cross-section of at least about 50 barns and a metal having a thermal conductivity of at least about 1 W/cmK. Apparatus for providing a neutron flux having a high fast-to-thermal neutron ratio may include a source of neutrons that produces fast neutrons and thermal neutrons. A neutron absorber positioned adjacent the neutron source absorbs at least some of the thermal neutrons so that a region adjacent the neutron absorber has a fast-to-thermal neutron ratio of at least about 15. A coolant in thermal contact with the neutron absorber removes heat from the neutron absorber.

  3. Use of Neutron Beams for Materials Research Relevant to the Nuclear Energy Sector. Annex: Individual Reports

    International Nuclear Information System (INIS)

    Nuclear technologies such as fission and fusion reactors, including associated waste storage and disposal, rely on the availability of not only nuclear fuels but also advanced structural materials. In 2010–2013, the IAEA organized and implemented the Coordinated Research Project (CRP) on Development, Characterization and Testing of Materials of Relevance to Nuclear Energy Sector Using Neutron Beams. A total of 19 institutions from 18 Member States (Argentina, Australia, Brazil, China, Czech Republic, France, Germany, Hungary, Indonesia, Italy, Japan, Netherlands, Republic of Korea, Romania, Russian Federation (two institutions), South Africa, Switzerland and United States of America) cooperated with the main objective to address the use of various neutron beam techniques for characterization, testing and qualification of materials and components produced or under development for applications in the nuclear energy sector. This CRP aimed to bring stakeholders and end users of research reactors and accelerator based neutron sources together for the enhanced use of available facilities and development of new infrastructures for applied materials research. Work envisioned under this CRP was related to the optimization and validation of neutron beam techniques, including facility and instrument modifications/optimizations as well as improved data acquisition, processing and analysis systems. Particular emphasis was placed on variable environments during material characterization and testing as required by some applications such as intensive irradiation load, high temperature and high pressure conditions, and the presence of strong magnetic fields. Targeted neutron beam techniques were neutron diffraction, small angle neutron scattering and digital neutron radiography/tomography. The publication IAEA-TECDOC-1773 is a compilation of the main results and findings of the CRP, and this CD-ROM accompanying the publication contains 19 reports with additional relevant

  4. Use of Neutron Beams for Materials Research Relevant to the Nuclear Energy Sector

    International Nuclear Information System (INIS)

    Nuclear technologies such as fission and fusion reactors, including associated waste storage and disposal, rely on the availability of not only nuclear fuels but also advanced structural materials. In 2010–2013, the IAEA organized and implemented the Coordinated Research Project (CRP) on Development, Characterization and Testing of Materials of Relevance to Nuclear Energy Sector Using Neutron Beams. A total of 19 institutions from 18 Member States (Argentina, Australia, Brazil, China, Czech Republic, France, Germany, Hungary, Indonesia, Italy, Japan, Netherlands, Republic of Korea, Romania, Russian Federation (two institutions), South Africa, Switzerland and United States of America) cooperated with the main objective to address the use of various neutron beam techniques for characterization, testing and qualification of materials and components produced or under development for applications in the nuclear energy sector. This CRP aimed to bring stakeholders and end users of research reactors and accelerator based neutron sources together for the enhanced use of available facilities and development of new infrastructures for applied materials research. Work envisioned under this CRP was related to the optimization and validation of neutron beam techniques, including facility and instrument modifications/optimizations as well as improved data acquisition, processing and analysis systems. Particular emphasis was placed on variable environments during material characterization and testing as required by some applications such as intensive irradiation load, high temperature and high pressure conditions, and the presence of strong magnetic fields. Targeted neutron beam techniques were neutron diffraction, small angle neutron scattering and digital neutron radiography/tomography. This publication is a compilation of the main results and findings of the CRP, and the CD-ROM accompanying this publication contains 19 reports with additional relevant technical details

  5. Neutron rich nuclei and neutron stars

    OpenAIRE

    Horowitz, C. J.

    2013-01-01

    The PREX experiment at Jefferson Laboratory measures the neutron radius of 208Pb with parity violating electron scattering in a way that is free from most strong interaction uncertainties. The 208Pb radius has important implications for neutron rich matter and the structure of neutron stars. We present first PREX results, describe future plans, and discuss a follow on measurement of the neutron radius of 48Ca. We review radio and X-ray observations of neutron star masses and radii. These cons...

  6. Advanced Computational Methods for Knowledge Engineering - Proceedings of the 4th International Conference on Computer Science, Applied Mathematics and Applications, ICCSAMA 2016, 2-3 May, 2016, Vienna, Austria

    OpenAIRE

    2016-01-01

    This proceedings consists of 20 papers which have been selected and invited from the submissions to the 4th International Conference on Computer Science, Applied Mathematics and Applications (ICCSAMA 2016) held on 2-3 May, 2016 in Laxenburg, Austria. The conference is organized into 5 sessions: Advanced Optimization Methods and Their Applications, Models for ICT applications, Topics on discrete mathematics, Data Analytic Methods and Applications and Feature Extractio, respectively. All chap...

  7. Development of a monoenergetic neutron beam (Theoretical aspects, experimental developments and applications); Desarrollo de un haz de neutrones monoenergeticos (Aspectos teoricos, desarrollos experimentales y aplicaciones)

    Energy Technology Data Exchange (ETDEWEB)

    Varela G, A

    2003-07-01

    By the use of a neutron time of flight system at the Tandem Accelerator of the National Nuclear Research Institute; with neutrons provided by means of the {sup 2} H(d, n) {sup 3} He we intend to use the associated particle technique in order to have monoenergetic neutrons. This neutron beam will be used both in basic and applied research. (Author)

  8. Advancing development of a limit reference point estimator for sea turtles, and evaluating methods for applying local management to highly migratory species

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — SWFSC is developing tools for estimation of limit reference points for marine turtles. These tools are being applied initially to estimate a limit reference point...

  9. Neutron reflectometry

    DEFF Research Database (Denmark)

    Klösgen-Buchkremer, Beate Maria

    2014-01-01

    Neutron (and X-ray) reflectometry constitute complementary interfacially sensitive techniques that open access to studying the structure within thin films of both soft and hard condensed matter. Film thickness starts oxide surfaces on bulk substrates, proceeding to (pauci-)molecular layers and up...... to hundreds of nanometers. Thickness resolution for flat surfaces is in the range of few Ǻngstrøm, and as a peculiar benefit, the presence and properties of buried interfaces are accessible. Focus here will be on neutron reflectometry, a technique that is unique in applications involving composite organic...... of new material. Understanding self-assembly of 2D-3D nanostructures at surfaces and the related interfaces in layered films is a precondition for the development of tailored tools with distributed functions, like new clothes (self-cleaning surfaces combined with mechanical resistance, low permeability...

  10. A retrospective study of external beam radiation, neutron brachytherapy, and concurrent chemotherapy for patients with localized advanced carcinoma of the esophagus

    International Nuclear Information System (INIS)

    The aim of this study was to retrospectively observe and analyze the long-term treatment outcomes of a total of 140 esophageal cancer patients who were treated with californium-252 (252Cf) neutron brachytherapy (NBT) in combination with external beam radiotherapy (EBRT) and concurrent chemotherapy (CCT). From January 2002 to November 2012, 140 patients with esophageal cancer underwent NBT in combination with EBRT and CCT. The distribution of the patient numbers over the various cancer stages of IIA, IIB, and III were 43, 7, and 90, respectively. The total radiation dose to the reference point via NBT was 8–25 Gy-eq in two to five fractions with one fraction per week. The total dose via EBRT was 50–60 Gy, which was delivered over a period of five to six weeks with normal fractionation. Fifty-four and 86 patients received tegafur suppositories (TS) and continuous infusion of fluorouracil (5-Fu) with cisplatin (CDDP), respectively. The median follow-up time was 42 months. The minimum follow-up was three months, and the maximum was 106 months. The overall median survival including death from all causes was 29.5 months. The five-year overall survival rate (OS) and local control (LC) were 33.4% and 55.9%, respectively. The chemotherapy regimen was a factor that was significantly associated with OS (p = 0.025) according to univariate analysis. The five-year OSs were 27.4% and 44.3% for the PF and TS chemotherapy regimens, respectively. Regarding acute toxicity, no incidences of fistula or massive bleeding were observed during this treatment period. The incidence of severe, late complications was related to the PF chemotherapy regimen (p = 0.080). The clinical data indicated that NBT in combination with EBRT and CRT produced favorable local control and long-term survival rates for patients with esophageal cancer and that the side effects were tolerable. A reasonable CRT regimen can decrease the rate of severe, late complications

  11. Neutron scattering. Lectures

    International Nuclear Information System (INIS)

    The following topics are dealt with: Neutron scattering in contemporary research, neutron sources, symmetry of crystals, diffraction, nanostructures investigated by small-angle neutron scattering, the structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic scattering, strongly correlated electrons, dynamics of macromolecules, applications of neutron scattering. (HSI)

  12. Neutron scattering. Lectures

    International Nuclear Information System (INIS)

    The following topics are dealt with: Neutron sources, symmetry of crystals, nanostructures investigated by small-angle neutron scattering, structure of macromolecules, spin dependent and magnetic scattering, structural analysis, neutron reflectometry, magnetic nanostructures, inelastic neutron scattering, strongly correlated electrons, polymer dynamics, applications of neutron scattering. (HSI)

  13. Neutron dosimetry

    International Nuclear Information System (INIS)

    It is the object of the present invention to provide a method of measuring neutron radiation which eliminates the use of powders as dosimeter target materials and reduces the requirement for repetitive weighing of dosimeters, for expensive radioisotopes as dosimeter target material, and for dosimeter housings (in many cases). The invention described is a method of measuring neutron radiation within a nuclear reactor consisting of placing one or more extruded sintered oxide wires comprising a dosimeter target oxide within the reactor and measuring the radioactivity induced in the wires by neutron radiation. These oxide wires consist of a dilution containing at least 0.1% by weight of the dosimeter target oxide in a diluent oxide. The diluent oxide is selected from a group consisting of Al2O3 and BeO. Almost any metal oxide may be used as a target oxide. The wires may be encapsulated within a co-extruded housing. These mixed oxide wires have been found to be sufficiently uniform for quantitative analyses. (JTA)

  14. Calibration of a special neutron dosemeter based on solid-state track detectors and fission radiators in various neutron fields

    International Nuclear Information System (INIS)

    The calibration of a personnel neutron dosemeter in different neutron fields is described. The badge-like dosemeter contains 5 detectors: polycarbonate foil (10 μm, Makrofol KG), 232Th, natural uranium, natural uranium with boron, and natural uranium with cadmium. Detector sensitivity and calibration factors have been calculated and measured in radiation fields of 252Cf fission neutrons, WWR-S reactor neutrons with and without Cd and Fe shielding, 3-MeV (d,t) generator neutrons, and 238PuBe neutrons. Measurement range and achievable accuracy are discussed from the point of view of applying the dosemeter in routine and emergency uses

  15. ATRC Neutron Detector Testing Quick Look Report

    Energy Technology Data Exchange (ETDEWEB)

    Troy C. Unruh; Benjamin M. Chase; Joy L. Rempe

    2013-08-01

    As part of the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) program, a joint Idaho State University (ISU) / French Alternative Energies and Atomic Energy Commission (CEA) / Idaho National Laboratory (INL) project was initiated in FY-10 to investigate the feasibility of using neutron sensors to provide online measurements of the neutron flux and fission reaction rate in the ATR Critical Facility (ATRC). A second objective was to provide initial neutron spectrum and flux distribution information for physics modeling and code validation using neutron activation based techniques in ATRC as well as ATR during depressurized operations. Detailed activation spectrometry measurements were made in the flux traps and in selected fuel elements, along with standard fission rate distribution measurements at selected core locations. These measurements provide additional calibration data for the real-time sensors of interest as well as provide benchmark neutronics data that will be useful for the ATR Life Extension Program (LEP) Computational Methods and V&V Upgrade project. As part of this effort, techniques developed by Prof. George Imel will be applied by Idaho State University (ISU) for assessing the performance of various flux detectors to develop detailed procedures for initial and follow-on calibrations of these sensors. In addition to comparing data obtained from each type of detector, calculations will be performed to assess the performance of and reduce uncertainties in flux detection sensors and compare data obtained from these sensors with existing integral methods employed at the ATRC. The neutron detectors required for this project were provided to team participants at no cost. Activation detectors (foils and wires) from an existing, well-characterized INL inventory were employed. Furthermore, as part of an on-going ATR NSUF international cooperation, the CEA sent INL three miniature fission chambers (one for detecting fast flux and two for

  16. Dosimetry methods in boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G.; Artuso, E.; Felisi, M.; Regazzoni, V.; Giove, D. [Universita degli Studi di Milano, Department of Physics, Via Festa del Patrono 7, 20122 Milano (Italy); Agosteo, S.; Barcaglioni, L. [Istituto Nazionale di Fisica Nucleare, Milano (Italy); Campi, F.; Garlati, L. [Politecnico di Milano, Energy Department, Piazza Leonardo Da Vinci 32, 20133 Milano (Italy); De Errico, F. [Universita degli Studi di Pisa, Department of Civil and Industrial Engineering, Lungamo Pacinotti 43, 56126 Pisa (Italy); Borroni, M.; Carrara, M. [Fondazione IRCCS Istituto Nazionale Tumori, Medical Physics Unit, Via Venezian 1, 20133 Milano (Italy); Burian, J.; Klupak, V.; Viererbl, L.; Marek, M. [Research Centre Rez, Department of Neutron Physics, 250-68 Husinec-Rez (Czech Republic)

    2014-08-15

    Dosimetry studies have been carried out at thermal and epithermal columns of Lvr-15 research reactor for investigating the spatial distribution of gamma dose, fast neutron dose and thermal neutron fluence. Two different dosimetry methods, both based on solid state detectors, have been studied and applied and the accuracy and consistency of the results have been inspected. One method is based on Fricke gel dosimeters that are dilute water solutions and have good tissue equivalence for neutrons and also for all the secondary radiations produced by neutron interactions in tissue or water phantoms. Fricke gel dosimeters give the possibility of separating the various dose contributions, i.e. the gamma dose, the fast neutron dose and the dose due to charged particles generated during thermal neutron reactions by isotopes having high cross section, like 10-B. From this last dose, thermal neutron fluence can be obtained by means of the kerma factor. The second method is based on thermoluminescence dosimeters. In particular, the developed method draw advantage from the different heights of the peaks of the glow curve of such phosphors when irradiated with photons or with thermal neutrons. The results show that satisfactory results can be obtained with simple methods, in spite of the complexity of the subject. However, the more suitable dosimeters and principally their utilization and analysis modalities are different for the various neutron beams, mainly depending on the relative intensities of the three components of the neutron field, in particular are different for thermal and epithermal columns. (Author)

  17. Dosimetry methods in boron neutron capture therapy

    International Nuclear Information System (INIS)

    Dosimetry studies have been carried out at thermal and epithermal columns of Lvr-15 research reactor for investigating the spatial distribution of gamma dose, fast neutron dose and thermal neutron fluence. Two different dosimetry methods, both based on solid state detectors, have been studied and applied and the accuracy and consistency of the results have been inspected. One method is based on Fricke gel dosimeters that are dilute water solutions and have good tissue equivalence for neutrons and also for all the secondary radiations produced by neutron interactions in tissue or water phantoms. Fricke gel dosimeters give the possibility of separating the various dose contributions, i.e. the gamma dose, the fast neutron dose and the dose due to charged particles generated during thermal neutron reactions by isotopes having high cross section, like 10-B. From this last dose, thermal neutron fluence can be obtained by means of the kerma factor. The second method is based on thermoluminescence dosimeters. In particular, the developed method draw advantage from the different heights of the peaks of the glow curve of such phosphors when irradiated with photons or with thermal neutrons. The results show that satisfactory results can be obtained with simple methods, in spite of the complexity of the subject. However, the more suitable dosimeters and principally their utilization and analysis modalities are different for the various neutron beams, mainly depending on the relative intensities of the three components of the neutron field, in particular are different for thermal and epithermal columns. (Author)

  18. PRODUCTION AND APPLICATIONS OF NEUTRONS USING PARTICLE ACCELERATORS

    Energy Technology Data Exchange (ETDEWEB)

    David L. Chichester

    2009-11-01

    Advances in neutron science have gone hand in hand with the development and of particle accelerators from the beginning of both fields of study. Early accelerator systems were developed simply to produce neutrons, allowing scientists to study their properties and how neutrons interact in matter, but people quickly realized that more tangible uses existed too. Today the diversity of applications for industrial accelerator-based neutron sources is high and so to is the actual number of instruments in daily use is high, and they serve important roles in the fields where they're used. This chapter presents a technical introduction to the different ways particle accelerators are used to produce neutrons, an historical overview of the early development of neutron-producing particle accelerators, a description of some current industrial accelerator systems, narratives of the fields where neutron-producing particle accelerators are used today, and comments on future trends in the industrial uses of neutron producing particle accelerators.

  19. Neutron visual sensing techniques making good use of computer science

    International Nuclear Information System (INIS)

    Neutron visual sensing technique is one of the nondestructive visualization and image-sensing techniques. In this article, some advanced neutron visual sensing techniques are introduced. The most up-to-date high-speed neutron radiography, neutron 3D CT, high-speed scanning neutron 3D/4D CT and multi-beam neutron 4D CT techniques are included with some fundamental application results. Oil flow in a car engine was visualized by high-speed neutron radiography technique to make clear the unknown phenomena. 4D visualization of pained sand in the sand glass was reported as the demonstration of the high-speed scanning neutron 4D CT technique. The purposes of the development of these techniques are to make clear the unknown phenomena and to measure the void fraction, velocity etc. with high-speed or 3D/4D for many industrial applications. (author)

  20. Neutron radiography at the HFR Petten

    International Nuclear Information System (INIS)

    This report contains the five papers on neutron radiography activities at the Petten High Flux Reactor (HFR) presented at the Third World Conference on Neutron Radiography which was held in May 1989 in Osaka, Japan. In addition, a survey on neutron radiography in Europe for industry and research as presented at the SITEF NDT symposium 1989 on European Advances in Non-Destructive Testing, held in Toulouse/France in October 1989 is included. The papers compiled here are concerned with: the neutron radiography services available in Petten; the experience with and applications of neutron radiography at Petten; image evaluation and analysis techniques at Petten; the practical utilization of nitrocellulose film in neutron radiography in Europe; an introduction into the basic principles of neutron radiography; an overview of the neutron radiography facilities in Europe for industry and research; and a survey of typical applications of neutron radiography in industry, research and sciences. It is the intention of this compilation to provide a comprehensive overview of the present Petten activities and European facilities in this young and promising field of non-destructive testing of materials and components from the nuclear and the non-nuclear industries and research organizations, and from the sciences

  1. The new neutron grating interferometer at the ANTARES beamline - Design, Principle, and Applications -

    OpenAIRE

    Reimann, Tommy; Mühlbauer, Sebastian; Horisberger, Michael; Böni, Peter; Schulz, Michael

    2016-01-01

    Neutron grating interferometry is an advanced method in neutron imaging that allows the simultaneous recording of the transmission, the differential phase and the dark-field image. Especially the latter has recently received high interest because of its unique contrast mechanism which marks ultra-small-angle neutron scattering within the sample. Hence, in neutron grating interferometry, an imaging contrast is generated by scattering of neutrons off micrometer-sized inhomogeneities. Although t...

  2. QPO observations related to neutron star equations of state

    Science.gov (United States)

    Stuchlik, Zdenek; Urbanec, Martin; Török, Gabriel; Bakala, Pavel; Cermak, Petr

    We apply a genetic algorithm method for selection of neutron star models relating them to the resonant models of the twin peak quasiperiodic oscillations observed in the X-ray neutron star binary systems. It was suggested that pairs of kilo-hertz peaks in the X-ray Fourier power density spectra of some neutron stars reflect a non-linear resonance between two modes of accretion disk oscillations. We investigate this concept for a specific neutron star source. Each neutron star model is characterized by the equation of state (EOS), rotation frequency Ω and central energy density ρc . These determine the spacetime structure governing geodesic motion and position dependent radial and vertical epicyclic oscillations related to the stable circular geodesics. Particular kinds of resonances (KR) between the oscillations with epicyclic frequencies, or the frequencies derived from them, can take place at special positions assigned ambiguously to the spacetime structure. The pairs of resonant eigenfrequencies relevant to those positions are therefore fully given by KR,ρc , Ω, EOS and can be compared to the observationally determined pairs of eigenfrequencies in order to eliminate the unsatisfactory sets (KR,ρc , Ω, EOS). For the elimination we use the advanced genetic algorithm. Genetic algorithm comes out from the method of natural selection when subjects with the best adaptation to assigned conditions have most chances to survive. The chosen genetic algorithm with sexual reproduction contains one chromosome with restricted lifetime, uniform crossing and genes of type 3/3/5. For encryption of physical description (KR,ρ, Ω, EOS) into chromosome we used Gray code. As a fitness function we use correspondence between the observed and calculated pairs of eigenfrequencies.

  3. Neutron star equation of state and QPO observations

    Science.gov (United States)

    Urbanec, Martin; Stuchlík, Zdeněk; Török, Gabriel; Bakala, Pavel; Čermák, Petr

    2007-12-01

    Assuming a resonant origin of the twin peak quasiperiodic oscillations observed in the X-ray neutron star binary systems, we apply a genetic algorithm method for selection of neutron star models. It was suggested that pairs of kilohertz peaks in the X-ray Fourier power density spectra of some neutron stars reflect a non-linear resonance between two modes of accretion disk oscillations. We investigate this concept for a specific neutron star source. Each neutron star model is characterized by the equation of state (EOS), rotation frequency Ω and central energy density rho_{c}. These determine the spacetime structure governing geodesic motion and position dependent radial and vertical epicyclic oscillations related to the stable circular geodesics. Particular kinds of resonances (KR) between the oscillations with epicyclic frequencies, or the frequencies derived from them, can take place at special positions assigned ambiguously to the spacetime structure. The pairs of resonant eigenfrequencies relevant to those positions are therefore fully given by KR, rho_{c}, Ω, EOS and can be compared to the observationally determined pairs of eigenfrequencies in order to eliminate the unsatisfactory sets (KR, rho_{c}, Ω, EOS). For the elimination we use the advanced genetic algorithm. Genetic algorithm comes out from the method of natural selection when subjects with the best adaptation to assigned conditions have most chances to survive. The chosen genetic algorithm with sexual reproduction contains one chromosome with restricted lifetime, uniform crossing and genes of type 3/3/5. For encryption of physical description (KR, rho_{c}, Ω, EOS) into the chromosome we use the Gray code. As a fitness function we use correspondence between the observed and calculated pairs of eigenfrequencies.

  4. Neutron stars as probes of extreme energy density matter

    Indian Academy of Sciences (India)

    Madappa Prakash

    2015-05-01

    Neutron stars have long been regarded as extraterrestrial laboratories from which we can learn about extreme energy density matter at low temperatures. In this article, some of the recent advances made in astrophysical observations and related theory are highlighted. Although the focus is on the much needed information on masses and radii of several individual neutron stars, the need for additional knowledge about the many facets of neutron stars is stressed. The extent to which quark matter can be present in neutron stars is summarized with emphasis on the requirement of non-perturbative treatments. Some longstanding and new questions, answers to which will advance our current status of knowledge, are posed.

  5. FLUENT-based neutronics and thermal-hydraulics coupling calculation for a liquid-fuel molten salt reactor

    International Nuclear Information System (INIS)

    Molten Salt Reactor (MSR) is the only one using liquid fuel in the six candidate reactors of the Generation IV advanced nuclear power systems with expected remarkable advantages in safety, economics, sustainability, and proliferation resistance. The strong coupling between neutronics and thermal-hydraulics due to fuel movement in the liquid-fuel MSRs induces many new challenges in reactor analyses from the perspective of both theoretical models and solution methods. In this study, the multi-group diffusion theory was adopted to deduce the neutronics model for the liquid-fuel MSRs, in which the salt flow effects on the delayed neutron precursor distributions in space were considered particularly. Since the liquid-fuel salt is a Newton fluid, the single-phase thermal hydraulics model for liquid-fuel MSRs was generally established based on the fundamental laws of the mass, momentum and energy conservation equations as used in the computational fluid dynamic (CFD) method. Since the control equations of the neutronic model can be written in the same form of those solved in the CFD softwares, a neutronics and thermal-hydraulics coupling scheme was proposed and a program was developed based on the FLUENT software by using its user-defined functions and subroutines (UDF and UDS). This program was applied to perform the steady state calculation of the molten salt fast reactor (MSFR), and the main results such as the space distributions of the neutron fluxes, delayed neutron precursors, temperatures, velocities were obtained. The results show that the liquid fuel flow influences the delayed neutron precursors significantly, while slightly affects the neutron fluxes. The flow in the MSFR core generates a vortex near the fertile tank leading the maximal temperature to about 1200 K at the centre of the vortex, which will be optimized in the future core design. (author)

  6. Neutron Resonance Spin Determination Using Multi-Segmented Detector DANCE

    International Nuclear Information System (INIS)

    A sensitive method to determine the spin of neutron resonances is introduced based on the statistical pattern recognition technique. The new method was used to assign the spins of s-wave resonances in 155Gd. The experimental neutron capture data for these nuclei were measured with the DANCE (Detector for Advanced Neutron Capture Experiment) calorimeter at the Los Alamos Neutron Science Center. The highly segmented calorimeter provided detailed multiplicity distributions of the capture γ-rays. Using this information, the spins of the neutron capture resonances were determined. With these new spin assignments, level spacings are determined separately for s-wave resonances with Jπ = 1- and 2-.

  7. Monte-Carlo Simulation on Neutron Instruments at CARR

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The design of high resolution neutron powder diffractometer(HRPD) and two cold neutron guides(CNGs) to be built at China advanced research reactor(CARR) are studied by Monte-Carlo simulation technique.The HRPD instrument is desiged to have a minimum resolution of 0.2% and neutron fluence rate of greater than 106 cm-2 ·s-1 at sample position. The resolution curves, neutron fluence rate and effective neutron beam size at sample position are given. Differences in resolutions and intensity between the

  8. Dhruva reactor -- a high flux facility for neutron beam research

    International Nuclear Information System (INIS)

    Dhruva reactor, the highest flux thermal neutron source in India has been operating at full power of 100 MW over the past two years. Several advanced facilities like the cold source, guides, etc. are being installed for neutron beam research in condensed matter. A large number and variety of neutron spectrometers are operational. This paper deals with the basic advantages that one can derive from neutron scattering investigations and gives a brief description of the instruments that are developed and commissioned at Dhruva for neutron beam research. (author). 3 figs

  9. Spallation Neutron Source (SNS)

    Data.gov (United States)

    Federal Laboratory Consortium — The SNS at Oak Ridge National Laboratory is a next-generation spallation neutron source for neutron scattering that is currently the most powerful neutron source in...

  10. Delayed neutrons as a probe of nuclear charge distribution in fission of heavy nuclei by neutrons

    CERN Document Server

    Isaev, S G; Piksaikin, V M; Roshchenko, V A

    2001-01-01

    A method of the determination of cumulative yields of delayed neutron precursors is developed. This method is based on the iterative least-square procedure applied to delayed neutron decay curves measured after irradiation of sup 2 sup 3 sup 5 U sample by thermal neutrons. Obtained cumulative yields in turns were used for deriving the values of the most probable charge in low-energy fission of the above-mentioned nucleus.

  11. The neutron-gamma Feynman variance to mean approach: gamma detection and total neutron-gamma detection (theory and practice)

    OpenAIRE

    Chernikova, Dina; Axell, Kåre; Avdic, Senada; Pázsit, Imre; Nordlund, Anders

    2014-01-01

    Two versions of the neutron-gamma variance to mean (Feynman-alpha method or Feynman-Y function) formula for either gamma detection only or total neutron-gamma detection, respectively, are derived and compared in this paper. The new formulas have a particular importance for detectors of either gamma photons or detectors sensitive to both neutron and gamma radiation. If applied to a plastic or liquid scintillation detector, the total neutron-gamma detection Feynman-Y expression corresponds to a...

  12. Design and operation of the double crystal monochromator for energy selective neutron imaging at ENF

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jongyul; Lim, Chang Hwy; Moon, Myung Kook; Kim, TaeJoo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Youngju; Lee, Seung Wook [Pusan National University, Pusan (Korea, Republic of)

    2015-05-15

    Energy selective neutron imaging is one of advanced neutron imaging techniques. Although conventional neutron imaging can't visualize a complex structure of polycrystalline because polychromatic thermal and cold neutron beams are mainly used, the detailed structure of the welded steel sample can be visualized using energy selective neutron imaging. Neutron imaging experiments have been performed at Ex-core Neutron irradiation Facility (ENF) in HANARO research reactor. To perform energy selective neutron imaging at ENF, a neutron beam with narrow energy band is needed. The double crystal monochromator that is well designed and prepared will be set up for energy selective neutron imaging at the Ex-core Neutron irradiation Facility (ENF) in HANARO.

  13. Design and operation of the double crystal monochromator for energy selective neutron imaging at ENF

    International Nuclear Information System (INIS)

    Energy selective neutron imaging is one of advanced neutron imaging techniques. Although conventional neutron imaging can't visualize a complex structure of polycrystalline because polychromatic thermal and cold neutron beams are mainly used, the detailed structure of the welded steel sample can be visualized using energy selective neutron imaging. Neutron imaging experiments have been performed at Ex-core Neutron irradiation Facility (ENF) in HANARO research reactor. To perform energy selective neutron imaging at ENF, a neutron beam with narrow energy band is needed. The double crystal monochromator that is well designed and prepared will be set up for energy selective neutron imaging at the Ex-core Neutron irradiation Facility (ENF) in HANARO

  14. Compact Neutron Generators for Medical, Home Land Security, and Planetary Exploration

    CERN Document Server

    Reijonen, Jani

    2005-01-01

    The Plasma and Ion Source Technology Group at Lawrence Berkeley National Laboratory has developed various types of advanced D-D (neutron energy 2.5 MeV), D-T (14 MeV) and T-T (0 - 9 MeV) neutron generators for wide range of applications. These applications include medical (Boron Neutron Capture Therapy), homeland security (Prompt Gamma Activation Analysis, Fast Neutron Activation Analysis and Pulsed Fast Neutron Transmission Spectroscopy) and planetary exploration in form of neutron based, sub-surface hydrogen detection systems. These neutron generators utilize RF induction discharge to ionize the deuterium/tritium gas. This discharge method provides high plasma density for high output current, high atomic species from molecular gases, long life operation and versatility for various discharge chamber geometries. Three main neutron generator developments are discussed here: high neutron output co-axial neutron generator for BNCT applications, point neutron generator for security applications, compact and sub-c...

  15. The Brazilian status on ADS R and D: Preliminary road map to a program on accelerator utilization on basic and applied nuclear physics, products and services and to drive an experimental neutron source sub critical facility

    International Nuclear Information System (INIS)

    the activities already underway in Nuclear Physics and Engineering, and preserves the identities and focus of the various institutions involved. ADS related research and development is being pursued by IPEN (design calculation, development of an Alternative Concept for a Fast Energy Amplifier). Moreover, IPEN operates a small cyclotrons, CV-28. The IPEN CV-28 cyclotron is presently not operational, but suitable for R and D: it is a compact, isochronous, multi-particle radiation source where protons, deuterons, 3He++, and alpha particles can be accelerated with variable energies up to 24, 14, 36, and 28 MeV respectively. Finally, IPEN is also operating the Cyclone-30 from IBA which is dedicated to radioisotope production (201-Tl, 123-I, 67-Ga), an electron accelerator used in high social and economic impact projects (e.g., food irradiation), and a Van de Graaff capable to provide a 14 MeV neutron source. The Physics Institute of Sao Paulo University-IFUSP is implementing various R and D activities/projects, in areas such as nuclear reactions with heavy ions, nuclear structure, photo nuclear reactions, ion implantation, non destructive techniques using accelerators beams. These programs are centered on IFUSP facilities, i.e., a heavy ion electrostatic accelerator (PELLETRON), a linear accelerator (LINAC), and an electron accelerator (MICROTRON), as well as associated experimental facilities. The institute is also performing theoretical research on nuclear reactions of interest to ADS (spallation-cascade evaporation model). Given the outlined scenario, IPEN-IFUSP have identified the possibility to launch a program on the utilization of accelerators. This programs would have three main pillars: R and D in basic and applied nuclear physics and engineering (e.g., low energy cross sections nuclear reactions, charged particle activation analysis, hydrogen implantation for angular correlation studies, excitation function determination, helium embrittlement in structural

  16. Neutron scattering. Lectures

    International Nuclear Information System (INIS)

    The following topics are dealt with: Neutron sources, neutron properties and elastic scattering, correlation functions measured by scattering experiments, symmetry of crystals, applications of neutron scattering, polarized-neutron scattering and polarization analysis, structural analysis, magnetic and lattice excitation studied by inelastic neutron scattering, macromolecules and self-assembly, dynamics of macromolecules, correlated electrons in complex transition-metal oxides, surfaces, interfaces, and thin films investigated by neutron reflectometry, nanomagnetism. (HSI)

  17. REFRACTIVE NEUTRON LENS

    OpenAIRE

    Petrov, P. V.; Kolchevsky, N.N.

    2013-01-01

    Compound concave refractive lenses are used for focusing neutron beam. Investigations of spectral and focusing properties of a refractive neutron lens are presented. Resolution of the imaging system on the base of refractive neutron lenses depends on material properties and parameters of neutron source. Model of refractive neutron lens are proposed. Results of calculation diffraction resolution and focal depth of refractive neutron lens are discussed.

  18. Neutron Capture Nucleosynthesis

    OpenAIRE

    Kiss, Miklos

    2016-01-01

    Heavy elements (beyond iron) are formed in neutron capture nucleosynthesis processes. We have proposed a simple unified model to investigate the neutron capture nucleosynthesis in arbitrary neutron density environment. We have also investigated what neutron density is required to reproduce the measured abundance of nuclei assuming equilibrium processes. We found both of these that the medium neutron density has a particularly important role at neutron capture nucleosynthesis. About these resu...

  19. Neutron scattering. Lectures

    Energy Technology Data Exchange (ETDEWEB)

    Brueckel, Thomas; Heger, Gernot; Richter, Dieter; Roth, Georg; Zorn, Reiner (eds.)

    2010-07-01

    The following topics are dealt with: Neutron sources, neutron properties and elastic scattering, correlation functions measured by scattering experiments, symmetry of crystals, applications of neutron scattering, polarized-neutron scattering and polarization analysis, structural analysis, magnetic and lattice excitation studied by inelastic neutron scattering, macromolecules and self-assembly, dynamics of macromolecules, correlated electrons in complex transition-metal oxides, surfaces, interfaces, and thin films investigated by neutron reflectometry, nanomagnetism. (HSI)

  20. An Applied Study of Implementation of the Advanced Decommissioning Costing Methodology for Intermediate Storage Facility for Spent Fuel in Studsvik, Sweden with special emphasis to the application of the Omega code

    Energy Technology Data Exchange (ETDEWEB)

    Kristofova, Kristina; Vasko, Marek; Daniska, Vladimir; Ondra, Frantisek; Bezak, Peter [DECOM Slovakia, spol. s.r.o., J. Bottu 2, SK-917 01 Trnava (Slovakia); Lindskog, Staffan [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

    2007-01-15

    The presented study is focused on an analysis of decommissioning costs for the Intermediate Storage Facility for Spent Fuel (FA) facility in Studsvik prepared by SVAFO and a proposal of the advanced decommissioning costing methodology application. Therefore, this applied study concentrates particularly in the following areas: 1. Analysis of FA facility cost estimates prepared by SVAFO including description of FA facility in Studsvik, summarised input data, applied cost estimates methodology and summarised results from SVAFO study. 2. Discussion of results of the SVAFO analysis, proposals for enhanced cost estimating methodology and upgraded structure of inputs/outputs for decommissioning study for FA facility. 3. Review of costing methodologies with the special emphasis on the advanced costing methodology and cost calculation code OMEGA. 4. Discussion on implementation of the advanced costing methodology for FA facility in Studsvik together with: - identification of areas of implementation; - analyses of local decommissioning infrastructure; - adaptation of the data for the calculation database; - inventory database; and - implementation of the style of work with the computer code OMEGA.

  1. Fundamental research with neutron interferometry

    International Nuclear Information System (INIS)

    The invention of neutron interferometry in 1974 stimulated many experiments related to the wave-particle dualism of quantum mechanics. Widely separated coherent beams can be produced within a perfect crystal interforemeter which can be influenced by nuclear, magnetic and gravitational interaction. High order interferences have been observed connected with the occurrence of an interferometric spectral modeling. This effect has been demonstrated by a proper post-selection procedure showing a persisting action of plane wave components outside the wave packets. The verification of the 4π-symmetry of spinor wave functions and of the spin superposition law at a macroscopic scale and the observation of gravitational effects including the Sagnac effect have been widely debated in literature. The coupling of the neutron magnetic moment to resonator coils permitted the coherent energy exchange between the neutron quantum system and the macroscopic resonator. This phenomenon provided the basis for the observation of the magnetic Josephson effect with an energy sensitivity of 10-19 eV. Partial beam path detection experiments are in close connection with the development of quantum mechanical measurement theory. The very high sensitivity of neutron interferometry may be used in future for new fundamental-, solid-state and nuclear-physics application. Further steps towards advanced neutron quantum optical methods are envisaged. (author)

  2. Real-Time Neutron Radiography at CARR

    Institute of Scientific and Technical Information of China (English)

    HE; Lin-feng; HAN; Song-bai; WANG; Hong-li; WU; Mei-mei; WEI; Guo-hai; WANG; Yu

    2012-01-01

    <正>A real-time detector system for neutron radiography based on CMOS camera has been designed for the thermal neutron imaging facility under construction at China Advanced Research Reactor (CARR). This system is equipped with a new scientific CMOS camera with 5.5 million pixels and speed up to 100 fps at full frame. The readout noise is less than 2.4 electron per pixel. It is capable of providing

  3. Neutron spectroscopy. Final report

    International Nuclear Information System (INIS)

    The researches carried by the Columbia University Department of Applied Physics and Nuclear Engineering, and its predecessors, in contract initially with the AEC, then with ERDA, and finally with DOE, had as its initial objective the measurement of fission cross sections and energy distributions of the fission fragments, as measured by pulse heights in detectors. These investigations sought to establish relations between the energy distributions and the quantum numbers of the resonances. In addition, some related, together with some unrelated, investigations were conducted. Progress is reported on measurements on the fissile isotopes, capture cross section measurements, theoretical developments, and the NEVIS synchrocyclotron pulsed neutron source

  4. Neutron Therapy Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Neutron Therapy Facility provides a moderate intensity, broad energy spectrum neutron beam that can be used for short term irradiations for radiobiology (cells)...

  5. Neutron scattering for analysis of processes in lithium-ion batteries

    International Nuclear Information System (INIS)

    The review is concerned with analysis and generalization of information on application of neutron scattering for elucidation of the structure of materials for rechargeable energy sources (mainly lithium-ion batteries) and on structural rearrangements in these materials occurring in the course of electrochemical processes. Applications of the main methods including neutron diffraction, small-angle neutron scattering, inelastic neutron scattering, neutron reflectometry and neutron introscopy are considered. Information on advanced neutron sources is presented and a number of typical experiments are outlined. The results of some studies of lithium-containing materials for lithium-ion batteries, carried out at IBR-2 pulsed reactor, are discussed. The bibliography includes 50 references

  6. Computational Methods for Multi-dimensional Neutron Diffusion Problems

    Energy Technology Data Exchange (ETDEWEB)

    Song Han

    2009-10-15

    Lead-cooled fast reactor (LFR) has potential for becoming one of the advanced reactor types in the future. Innovative computational tools for system design and safety analysis on such NPP systems are needed. One of the most popular trends is coupling multi-dimensional neutron kinetics (NK) with thermal-hydraulic (T-H) to enhance the capability of simulation of the NPP systems under abnormal conditions or during rare severe accidents. Therefore, various numerical methods applied in the NK module should be reevaluated to adapt the scheme of coupled code system. In the author's present work a neutronic module for the solution of two dimensional steady-state multigroup diffusion problems in nuclear reactor cores is developed. The module can produce both direct fluxes as well as adjoints, i.e. neutron importances. Different numerical schemes are employed. A standard finite-difference (FD) approach is firstly implemented, mainly to serve as a reference for less computationally challenging schemes, such as transverse-integrated nodal methods (TINM) and boundary element methods (BEM), which are considered in the second part of the work. The validation of the methods proposed is carried out by comparisons of the results for some reference structures. In particular a critical problem for a homogeneous reactor for which an analytical solution exists is considered as a benchmark. The computational module is then applied to a fast spectrum system, having physical characteristics similar to the proposed European Lead-cooled System (ELSY) project. The results show the effectiveness of the numerical techniques presented. The flexibility and the possibility to obtain neutron importances allow the use of the module for parametric studies, design assessments and integral parameter evaluations, as well as for future sensitivity and perturbation analyses and as a shape solver for time-dependent procedures

  7. Development of a monoenergetic neutron beam (Theoretical aspects, experimental developments and applications)

    International Nuclear Information System (INIS)

    By the use of a neutron time of flight system at the Tandem Accelerator of the National Nuclear Research Institute; with neutrons provided by means of the 2 H(d, n) 3 He we intend to use the associated particle technique in order to have monoenergetic neutrons. This neutron beam will be used both in basic and applied research. (Author)

  8. Development of a monoenergetic neutron beam (Theoretical aspects, experimental developments and applications)

    CERN Document Server

    Varela-G, A

    2003-01-01

    By the use of a neutron time of flight system at the Tandem Accelerator of the National Nuclear Research Institute; with neutrons provided by means of the sup 2 H(d, n) sup 3 He we intend to use the associated particle technique in order to have monoenergetic neutrons. This neutron beam will be used both in basic and applied research. (Author)

  9. Neutron Damage and MAX Phase Ternary Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Barsoum, Michael [Drexel Univ., Philadelphia, PA (United States); Hoffman, Elizabeth [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Sindelar, Robert [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Garcua-Duaz, Brenda [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kohse, Gordon [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2014-06-17

    The Demands of Gen IV nuclear power plants for long service life under neutron radiation at high temperature are severe. Advanced materials that would withstand high temperatures (up to 1000+ C) to high doses in a neutron field would be ideal for reactor internal structures and would add to the long service life and reliability of the reactors. The objective of this work is to investigate the response of a new class of machinable, conductive, layered, ternary transition metal carbides and nitrides - the so-called MAX phases - to low and moderate neutron dose levels.

  10. Neutron Scattering in Biology Techniques and Applications

    CERN Document Server

    Fitter, Jörg; Katsaras, John

    2006-01-01

    The advent of new neutron facilities and the improvement of existing sources and instruments world wide supply the biological community with many new opportunities in the areas of structural biology and biological physics. The present volume offers a clear description of the various neutron-scattering techniques currently being used to answer biologically relevant questions. Their utility is illustrated through examples by some of the leading researchers in the field of neutron scattering. This volume will be a reference for researchers and a step-by-step guide for young scientists entering the field and the advanced graduate student.

  11. Advanced nanoelectronics

    CERN Document Server

    Ismail, Razali

    2012-01-01

    While theories based on classical physics have been very successful in helping experimentalists design microelectronic devices, new approaches based on quantum mechanics are required to accurately model nanoscale transistors and to predict their characteristics even before they are fabricated. Advanced Nanoelectronics provides research information on advanced nanoelectronics concepts, with a focus on modeling and simulation. Featuring contributions by researchers actively engaged in nanoelectronics research, it develops and applies analytical formulations to investigate nanoscale devices. The

  12. Neutron Computed Tomography Using Real-Time Neutron Radiography.

    Science.gov (United States)

    Sulcoski, Mark Francis

    Conventional neutron radiography of an object records a two-dimensional distribution of the neutron beam intensity after it has passed through an object. The neutron radiograph, whether static film or real-time, may be considered a "shadow graph" of the object. In a shadow graph, internal structures in an object may mask one another making it difficult or impossible to precisely define the internals of the object. This problem can be solved by tomographic imaging. A real-time neutron radiography facility was constructed including the capability of neutron tomography. The neutron beam was measured for total neutron flux ((1.0 (+OR-) 0.2) x 10('11) n/(m('2)-sec)), gold cadmium ratio (52 (+OR-) 3) and effective neutron temperature (83(DEGREES)C (+OR -) 8(DEGREES)C). The angular divergence or nonparallelism of the neutron beam was measured to be \\2.3(DEGREES) (+OR -) 0.1(DEGREES) thereby providing a means of quantifying the collimator effectiveness. The resolution capabilities of both static film and real-time neutron radiographs were quantified using a Fourier transform algorithm to calculate the modulation transfer function of both types of radiographs. The contrast sensitivity of both types of radiographs was measured as 3.1% for film and 4.0% for real-time radiographs. Two tomography algorithms, the simultaneous iterative reconstruction technique (SIRT) and the convolution method, were programmed on an Intellect 100 Image Processing System. The SIRT algorithm was found to be too large and slow on the Intellect 100 to produce useful tomographs. The convolution method produced results near the theoretical resolution limits for a given number of projections. A tomographic resolution of at least 1.3 mm was demonstrated using 200 projections. Computer running time for the convolution method was found to be (TURN)30 seconds for each projection used. A series of experiments were conducted using the convolution method investigating the effect of high and low pass

  13. Nucleosynthesis involving mainly neutron capture processes IV

    International Nuclear Information System (INIS)

    Nucleosynthesis plays a crucial role in the physics of stellar evolution. Heavy nuclei abundances in the universe provide a concrete evidence for the operation of specific nucleosynthesis processes. The slow (s-) and rapid (r-) processes are the main processes responsible for the synthesis of nuclei beyond iron. i.e. synthesis of nuclei heavier than Fe by neutron capture. In the preceding papers, (Paper I, Paper II, Paper III) we have reviewed important neutron capture processes in investigating the mechanism of stellar nucleosynthesis, i.e. various neutron producing reactions (neutron sources) during stellar nucleosynthesis in different evolving stages - main sequence stage, red giant stage, supernova stage and neutron star stage. Neutrons produced in one stage come into next stage as remnant and play an active role to begin nucleosynthesis in the next stage, and ultimately to the formation of neutron star. We have indicated various constraints and unsolved problems in each stage. With the help of advanced observational technology and numerical simulations considerable efforts have been made to resolve the unsolved problems in nuclear astrophysics in recent years. Analysis of those observed parameters may give rise to significant improvement towards understanding the physics of stellar nucleosynthesis. In the present review, we have updated our previous attempt by incorporating those significant improvements in the theory of neutron capture nucleosynthesis based upon observations, theoretical calculations and numerical simulations. (author)

  14. Neutron imaging of water penetration into cracked steel reinforced concrete

    International Nuclear Information System (INIS)

    Service life and durability of reinforced concrete structures have become a crucial issue because of the economical and ecological implications. Service life of reinforced concrete structures is often limited by penetration of water and chemical compounds dissolved in water into the porous cement-based material. By now it is well-known that cracks in reinforced concrete are preferential paths for ingress of aggressive substances. Neutron radiography was successfully applied to study the process of water penetration into cracked steel reinforced concrete. In addition, the effectiveness of integral water repellent concrete to prevent ingress of water and salt solutions was investigated. Results are described in detail in this contribution. It will be shown that neutron radiography is a powerful method to visualize the process of water penetration into cracked and uncracked cement-based materials. On the basis of the obtained experimental data, it is possible to quantify the time-dependent water distributions in concrete with high accuracy and spatial resolution. It is of particular interest that penetration of water and salt solutions into damaged interfaces between concrete and steel can be visualized by means of neutron radiography. Deteriorating processes in cracked reinforced concrete structures can be studied in a completely new way. This advanced technology will help and find adequate ways to improve durability and service life of reinforced concrete structures. This will mean at the same time an essential contribution to improved sustainability.

  15. Neutron imaging of water penetration into cracked steel reinforced concrete

    Science.gov (United States)

    Zhang, P.; Wittmann, F. H.; Zhao, T.; Lehmann, E. H.

    2010-04-01

    Service life and durability of reinforced concrete structures have become a crucial issue because of the economical and ecological implications. Service life of reinforced concrete structures is often limited by penetration of water and chemical compounds dissolved in water into the porous cement-based material. By now it is well-known that cracks in reinforced concrete are preferential paths for ingress of aggressive substances. Neutron radiography was successfully applied to study the process of water penetration into cracked steel reinforced concrete. In addition, the effectiveness of integral water repellent concrete to prevent ingress of water and salt solutions was investigated. Results are described in detail in this contribution. It will be shown that neutron radiography is a powerful method to visualize the process of water penetration into cracked and uncracked cement-based materials. On the basis of the obtained experimental data, it is possible to quantify the time-dependent water distributions in concrete with high accuracy and spatial resolution. It is of particular interest that penetration of water and salt solutions into damaged interfaces between concrete and steel can be visualized by means of neutron radiography. Deteriorating processes in cracked reinforced concrete structures can be studied in a completely new way. This advanced technology will help and find adequate ways to improve durability and service life of reinforced concrete structures. This will mean at the same time an essential contribution to improved sustainability.

  16. Treating leachate with advanced oxidation: applying Fenton's reagent; Oxidaciones avanzadas para el tratamiento de lixiviado: aplicacion del Reactivo de Fenton

    Energy Technology Data Exchange (ETDEWEB)

    Maranonn Ruiz, I.; Sancho Seuma, L.

    2003-07-01

    The present study investigates the removal of refractory organics by Advanced Oxidation Process: Fenton's Reaction. A batch test protocol was designed to study the oxidation and coagulation in Fenton Reaction. The batch tests were conducted to determine the optimum conditions for the plant operation such as pH, H{sub 2}O{sub 2} dosage, FeSO{sub 4} dosage and contact time. It was found that the highest removal efficiencies of COD were with the oxidation at acid pH around 3 and the coagulation at basic pH around 8, few minutes of treatment time, the initial concentrations of H{sub 2}O{sub 2} were in the range 68-1550 mg/l and the different dosages of FeSO{sub 4} were in the range 487-3038 mg/l. They were added in determinate proportions to get the highest efficiency of producing OH, DBO{sub 5}/DQO ratio was decreased from 0,3 to 0,1. Therefore Fenton's reaction process is a very effective means for a pretreatment or tertiary treatment of biological methods. (Author) 20 refs.

  17. Grazing-Incidence Neutron Optics based on Wolter Geometries

    Science.gov (United States)

    Gubarev, M. V.; Ramsey, B. D.; Mildner, D. F. R.

    2008-01-01

    The feasibility of grazing-incidence neutron imaging optics based on the Wolter geometries have been successfully demonstrated. Biological microscopy, neutron radiography, medical imaging, neutron crystallography and boron neutron capture therapy would benefit from high resolution focusing neutron optics. Two bounce optics can also be used to focus neutrons in SANS experiments. Here, the use of the optics would result in lower values of obtainable scattering angles. The high efficiency of the optics permits a decrease in the minimum scattering vector without lowering the neutron intensity on sample. In this application, a significant advantage of the reflective optics over refractive optics is that the focus is independent of wavelength, so that the technique can be applied to polychromatic beams at pulsed neutron sources.

  18. A pulsed neutron Ramsey's method

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Y. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba-shi, Ibaraki 305-0801 (Japan)]. E-mail: yasuhiro.masuda@kek.jp; Ino, T. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba-shi, Ibaraki 305-0801 (Japan); Jeong, S.C. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba-shi, Ibaraki 305-0801 (Japan); Muto, S. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba-shi, Ibaraki 305-0801 (Japan); Skoy, V. [Joint Institute for Nuclear Reasearch, 141980 Dubna (Russian Federation); Watanabe, Y. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba-shi, Ibaraki 305-0801 (Japan)

    2005-02-15

    A Ramsey's method with pulsed neutrons is proposed. A Ramsey signal, which is a neutron spin rotation about a static magnetic field for a time interval between two separated oscillatory fields, is observed as a function of a neutron time of flight (TOF) in this method. The neutron spin rotation or the RF oscillation is used as a clock of the neutron velocity measurement which ranges from cold to epithermal neutron energies. This method together with the TOF measurement can be used for neutron inelastic scattering experiments. In addition, this method can be applied to the measurement of magnetic and pseudomagnetic fields in matter, and also to neutron spin manipulation for spin dependent scattering.

  19. Neutron source for Neutron Capture Synovectomy

    International Nuclear Information System (INIS)

    Monte Carlo calculations were performed to obtain a thermal neutron field from a 239PuBe neutron source inside a cylindrical heterogeneous moderators for Neutron Capture Synovectomy. Studied moderators were light water and heavy water, graphite and heavy water, lucite and polyethylene and heavy water. The neutron spectrum of polyethylene and heavy water moderator was used to determine neutron spectra inside a knee model. In this model the elemental composition of synovium and synovial liquid was assumed like blood. Kerma factors for synovium and synovial liquid were calculated to compare with water Kerma factors, in this calculations the synovium was loaded with two different concentrations of Boron

  20. Saving Salmon Through Advances in Fluvial Remote Sensing: Applying the Optimal Band Ratio Analysis (OBRA) for Bathymetric Mapping of Over 250 km of River Channel and Habitat Classification

    Science.gov (United States)

    Richardson, R.; Legleiter, C. J.; Harrison, L.

    2015-12-01

    Salmonids are threatened with extinction across the world from the fragmentation of riverine ecosystems from dams and diversions. In California, efforts to expand the range of spawnable habitat for native salmon by transporting fish around reservoirs is a potentially species saving idea. But, strong scientific evidence of the amount of high quality habitat is required to make these difficult management decisions. Remote sensing has long been used in fluvial settings to identify physical parameters that drive the quality of aquatic habitat; however, the true strength of remote sensing to cover large spatial extents has not been applied with the resolution that is relevant to salmonids. This project utilizes hyperspectral data of over 250 km of the Tuolumne and Merced Rivers to extract depth and bed slope from the wetted channel and NIR LiDAR for the surrounding topography. The Optimal Band Ratio Analysis (OBRA) has proven as an effective tool to create bathymetric maps of river channels in ideal settings with clear water, high amounts of bottom reflectance, and less than 3 meters deep over short distances. Results from this study show that OBRA can be applied over larger riverscapes at high resolutions (0.5 m). The depth and bed slope estimations are used to classify habitat units that are crucial to quantifying the quality and amount of habitat in these river that once produced large populations of native salmonids. As more managers look to expand habitat for these threatened species the tools developed here will be cost effective over the large extents that salmon migrate to spawn.