Neutronic control instrumentation of protection systems

International Nuclear Information System (INIS)

Furet, J.

1977-01-01

The aims of neutronic control instrumentation are briefly recalled and the present status of materials research and development is presented. As for the out-of-pile instrumentation, emphasis is put on the reliability and efficiency of the detectors and the new solutions of electric signal processing. The possible reactivity measurements at rest are examined. As for in-pile instrumentation results relating to mobile detectors of the type of miniaturized fission chambers are presented. The radiation tests on course of development for several years in the working conditions of neutron self-powdered detectors are analyzed so as to show that their use as built-in in-core instrumentation is to be envisaged at short term. Basic options inherent to the 'Nuclear Safety' philosophy that define the protection system are recalled. A definition and a justification of the performance testing of the instrumentation at rest and in-service are then derived. Some new solutions are envisaged for processing the digital data obtained from the various sensors . A quality control of the materials setting conditions (especially electric noise) ensures a high reliability and availability of the materials involved in the neutron control and the protection system in working conditions [fr

Proceedings of a workshop on methods for neutron scattering instrumentation design

International Nuclear Information System (INIS)

Hjelm, R.P.

1997-09-01

The future of neutron and x-ray scattering instrument development and international cooperation was the focus of the workshop. The international gathering of about 50 participants representing 15 national facilities, universities and corporations featured oral presentations, posters, discussions and demonstrations. Participants looked at a number of issues concerning neutron scattering instruments and the tools used in instrument design. Objectives included: (1) determining the needs of the neutron scattering community in instrument design computer code and information sharing to aid future instrument development, (2) providing for a means of training scientists in neutron scattering and neutron instrument techniques, and (3) facilitating the involvement of other scientists in determining the characteristics of new instruments that meet future scientific objectives, and (4) fostering international cooperation in meeting these needs. The scope of the meeting included: (1) a review of x-ray scattering instrument design tools, (2) a look at the present status of neutron scattering instrument design tools and models of neutron optical elements, and (3) discussions of the present and future needs of the neutron scattering community. Selected papers were abstracted separately for inclusion to the Energy Science and Technology Database

Proceedings of a workshop on methods for neutron scattering instrumentation design

Energy Technology Data Exchange (ETDEWEB)

Hjelm, R.P. [ed.] [Los Alamos National Lab., NM (United States)

1997-09-01

The future of neutron and x-ray scattering instrument development and international cooperation was the focus of the workshop. The international gathering of about 50 participants representing 15 national facilities, universities and corporations featured oral presentations, posters, discussions and demonstrations. Participants looked at a number of issues concerning neutron scattering instruments and the tools used in instrument design. Objectives included: (1) determining the needs of the neutron scattering community in instrument design computer code and information sharing to aid future instrument development, (2) providing for a means of training scientists in neutron scattering and neutron instrument techniques, and (3) facilitating the involvement of other scientists in determining the characteristics of new instruments that meet future scientific objectives, and (4) fostering international cooperation in meeting these needs. The scope of the meeting included: (1) a review of x-ray scattering instrument design tools, (2) a look at the present status of neutron scattering instrument design tools and models of neutron optical elements, and (3) discussions of the present and future needs of the neutron scattering community. Selected papers were abstracted separately for inclusion to the Energy Science and Technology Database.

Electronic instrumentation system for pulsed neutron measurements

International Nuclear Information System (INIS)

Burda, J.; Igielski, A.; Kowalik, W.

1982-01-01

An essential point of pulsed neutron measurement of thermal neutron parameters for different materials is the registration of the thermal neutron die-away curve after a fast neutron bursts have been injected into the system. An electronic instrumentation system which is successfully applied for pulsed neutron measurements is presented. An important part of the system is the control unit which has been designed and built in the Laboratory of Neutron Parameters of Materials. (author)

A new design of neutron survey instrument

International Nuclear Information System (INIS)

Tanner, R.J.; Eakins, J.S.; Hager, L.G.

2010-01-01

A novel design of neutron survey instrument has been developed. The moderator has been modified via the use of 'neutron guides', which help thermal neutrons reach the central proportional counter. This innovation has allowed the variations in the energy dependence of ambient dose equivalent response to be reduced compared to prior single-detector designs, whilst maintaining a relatively light moderator and simple construction. In particular, the design has a relatively small over-response to neutrons with energies around 5 keV, when compared to prior designs. The final optimized design has been verified using MCNP5 calculations to ensure that the response is relatively independent of the energy and direction of the incident neutron. This has required the ends of the guides to be structured so that unidirectional and isotropic neutron fields have closely matched responses, as is necessary in the workplace. The reading of the instrument in workplace fields is calculated via folding and the suitability of the design for use in the workplace discussed.

ALADIN - Advanced Laue Diffraction Instruments using Neutrons

International Nuclear Information System (INIS)

Lemee-Cailleau, M.H.; Ouladdiaf, B.; McIntyre, G.J.

2011-01-01

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)

VESUVIO: a novel instrument for performing spectroscopic studies in condensed matter with eV neutrons at the ISIS facility

Science.gov (United States)

Senesi, R.; Andreani, C.; Bowden, Z.; Colognesi, D.; Degiorgi, E.; Fielding, A. L.; Mayers, J.; Nardone, M.; Norris, J.; Praitano, M.; Rhodes, N. J.; Stirling, W. G.; Tomkinson, J.; Uden, C.

2000-03-01

The VESUVIO project aims to provide unique prototype instrumentation at the ISIS-pulsed neutron source and to establish a routine experimental and theoretical program in neutron scattering spectroscopy at eV energies. This instrumentation will be specifically designed for high momentum, (20 Å-11 eV) inelastic neutron scattering studies of microscopic dynamical processes in materials and will represent a unique facility for EU researchers. It will allow to derive single-particle kinetic energies and single-particle momentum distributions, n(p), providing additional and/or complementary information to other neutron inelastic spectroscopic techniques.

Evolutionary programming for neutron instrument optimisation

Energy Technology Data Exchange (ETDEWEB)

Bentley, Phillip M. [Hahn-Meitner Institut, Glienicker Strasse 100, D-14109 Berlin (Germany)]. E-mail: phillip.bentley@hmi.de; Pappas, Catherine [Hahn-Meitner Institut, Glienicker Strasse 100, D-14109 Berlin (Germany); Habicht, Klaus [Hahn-Meitner Institut, Glienicker Strasse 100, D-14109 Berlin (Germany); Lelievre-Berna, Eddy [Institut Laue-Langevin, 6 rue Jules Horowitz, BP 156, 38042 Grenoble Cedex 9 (France)

2006-11-15

Virtual instruments based on Monte-Carlo techniques are now integral part of novel instrumentation development and the existing codes (McSTAS and Vitess) are extensively used to define and optimise novel instrumental concepts. Neutron spectrometers, however, involve a large number of parameters and their optimisation is often a complex and tedious procedure. Artificial intelligence algorithms are proving increasingly useful in such situations. Here, we present an automatic, reliable and scalable numerical optimisation concept based on the canonical genetic algorithm (GA). The algorithm was used to optimise the 3D magnetic field profile of the NSE spectrometer SPAN, at the HMI. We discuss the potential of the GA which combined with the existing Monte-Carlo codes (Vitess, McSTAS, etc.) leads to a very powerful tool for automated global optimisation of a general neutron scattering instrument, avoiding local optimum configurations.

Evolutionary programming for neutron instrument optimisation

International Nuclear Information System (INIS)

Bentley, Phillip M.; Pappas, Catherine; Habicht, Klaus; Lelievre-Berna, Eddy

2006-01-01

Virtual instruments based on Monte-Carlo techniques are now integral part of novel instrumentation development and the existing codes (McSTAS and Vitess) are extensively used to define and optimise novel instrumental concepts. Neutron spectrometers, however, involve a large number of parameters and their optimisation is often a complex and tedious procedure. Artificial intelligence algorithms are proving increasingly useful in such situations. Here, we present an automatic, reliable and scalable numerical optimisation concept based on the canonical genetic algorithm (GA). The algorithm was used to optimise the 3D magnetic field profile of the NSE spectrometer SPAN, at the HMI. We discuss the potential of the GA which combined with the existing Monte-Carlo codes (Vitess, McSTAS, etc.) leads to a very powerful tool for automated global optimisation of a general neutron scattering instrument, avoiding local optimum configurations

Current studies of biological materials using instrumental and radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Fardy, J.J.; McOrist, G.D.; Farrar, Y.J.

1985-01-01

Instrumental neutron activation analysis still remains the preferred option when analysing the trace element distribution in a wide rage of materials by neutron activation analysis. However, when lower limits of detection are required or major interferences reduce the effectiveness of this technique, radiochemical neutron activation analysis is applied. This paper examines the current use of both methods and the development of rapid radiochemical techniques for analysis of the biological materials, hair, cow's milk, human's milk, milk powder, blood and blood serum

Status of the Neutron Imaging and Diffraction Instrument IMAT

Science.gov (United States)

Kockelmann, Winfried; Burca, Genoveva; Kelleher, Joe F.; Kabra, Saurabh; Zhang, Shu-Yan; Rhodes, Nigel J.; Schooneveld, Erik M.; Sykora, Jeff; Pooley, Daniel E.; Nightingale, Jim B.; Aliotta, Francesco; Ponterio, Rosa C.; Salvato, Gabriele; Tresoldi, Dario; Vasi, Cirino; McPhate, Jason B.; Tremsin, Anton S.

A cold neutron imaging and diffraction instrument, IMAT, is currently being constructed at the ISIS second target station. IMAT will capitalize on time-of-flight transmission and diffraction techniques available at a pulsed neutron source. Analytical techniques will include neutron radiography, neutron tomography, energy-selective neutron imaging, and spatially resolved diffraction scans for residual strain and texture determination. Commissioning of the instrument will start in 2015, with time-resolving imaging detectors and two diffraction detector prototype modules. IMAT will be operated as a user facility for material science applications and will be open for developments of time-of-flight imaging methods.

Current status of some neutron instruments in Serpong

Energy Technology Data Exchange (ETDEWEB)

Ikram, A; Hardi, T; Maulana, A [Neutron Scattering Lab., Materials Science Research Center, BATAN-Serpong, Jakarta (Indonesia)

1998-10-01

Performances of the Small Angle Neutron Scattering Spectrometer, the High Resolution Small Angle Neutron Scattering Spectrometer and the High Resolution Neutron Powder Diffractometer in the last full one year are presented as well as problems, difficulties and limitations faced by each instrument. Efforts that have been done to overcome those shortcomings are also mentioned. Proposed collaboration in order to bring those instruments back to a state that can perform scientifically acceptable is described to a level that can be agreed in this workshop. (author)

A 'hybrid' neutron area survey instrument for the determination of neutron dose quantities in the workplace

International Nuclear Information System (INIS)

Tanner, R.J.; Jenkins, R.; Lowe, T.; Silvie, J.; Joyce, M.J.; Winsby, A.; Molinos, C.

2005-01-01

Full text: Neutron survey instruments are used routinely to determine the dose rates in areas where persons may be occupationally exposed. With a few exceptions, these instruments generally use a proportional counter with a high thermal neutron response located in a moderating sphere of CH 2 . The moderating sphere in such designs contains a thermal neutron absorber to reduce the over-response to thermal and intermediate energy neutrons. However, the commercially available examples of such instruments tend to have strongly energy dependent ambient dose equivalent response characteristics. In particular, they often over-respond in the energy range between 1 eV and 10 keV. A prototype of a novel design has been produced that uses seven detectors located in a moderating sphere of CH 2 , six near the surface to detect thermal and epithermal neutrons, and one in the centre to detect fast neutrons. This has been characterized using a combination of MCNP modelling and measurements to produce an instrument that has improved energy dependence of response characteristics. Additionally, the use of seven detectors offers direction and field hardness information. The design and calibration of the instrument are described and its response in workplaces calculated. (author)

Data acquisition system for the neutron scattering instruments at the intense pulsed neutron source

International Nuclear Information System (INIS)

Crawford, R.K.; Daly, R.T.; Haumann, J.R.; Hitterman, R.L.; Morgan, C.B.; Ostrowski, G.E.; Worlton, T.G.

1981-01-01

The Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory is a major new user-oriented facility which is now coming on line for basic research in neutron scattering and neutron radiation damage. This paper describes the data-acquisition system which will handle data acquisition and instrument control for the time-of-flight neutron-scattering instruments at IPNS. This discussion covers the scientific and operational requirements for this system, and the system architecture that was chosen to satisfy these requirements. It also provides an overview of the current system implementation including brief descriptions of the hardware and software which have been developed

Standardization of portable assay instrumentation: the neutron-coincidence tree

International Nuclear Information System (INIS)

Menlove, H.O.

1983-01-01

Standardization of portable neutron assay instrumentation has been achieved by using the neutron coincidence technique as a common basis for a wide range of instruments and applications. The electronics originally developed for the High-Level Neutron Coincidence Counter has been adapted to both passive- and active-assay instrumentation for field verification of bulk plutonium, inventory samples, pellets, powders, nitrates, high-enriched uranium, and materials-testing-reactor, light-water-reactor, and mixed-oxide fuel assemblies. The family of detectors developed at Los Alamos National Laboratory and their performance under in-field conditions are described. 16 figures, 3 tables

Practical implications of neutron survey instrument performance

International Nuclear Information System (INIS)

Tanner, R. J.; Bartlett, D. T.; Hager, I. G.; Jones, I. N.; Molinos, C.; Roberts, N. J.; Taylor, G. C.; Thomas, D. J.

2004-01-01

Improvements have been made to the Monte Carlo modelling used to calculate the response of the neutron survey instruments most commonly used in the UK, for neutron energies up to 20 MeV. The improved modelling of the devices includes the electronics and battery pack, allowing better calculations of both the energy and angle dependence of response. These data are used to calculate the response of the instruments in rotationally and fully isotropic, as well as unidirectional fields. Experimental measurements with radionuclide sources and monoenergetic neutron fields have been, and continue to be made, to test the calculated response characteristics. The enhancements to the calculations have involved simulation of the sensitivity of the response to variations in instrument manufacture, and will include the influence of the user and floor during measurements. The practical implications of the energy and angle dependence of response, variations in manufacture, and the influence of the user are assessed by folding the response characteristics with workplace energy and direction distributions. (authors)

Instrumentation at pulsed neutron sources

International Nuclear Information System (INIS)

Carpenter, J.M.; Lander, G.H.; Windsor, C.G.

1984-01-01

Scientific investigations involving the use of neutron beams have been centered at reactor sources for the last 35 years. Recently, there has been considerable interest in using the neutrons produced by accelerator driven (pulsed) sources. Such installations are in operation in England, Japan, and the United States. In this article a brief survey is given of how the neutron beams are produced and how they can be optimized for neutron scattering experiments. A detailed description is then given of the various types of instruments that have been, or are planned, at pulsed sources. Numerous examples of the scientific results that are emerging are given. An attempt is made throughout the article to compare the scientific opportunities at pulsed sources with the proven performance of reactor installations, and some familiarity with the latter and the general field of neutron scattering is assumed. New areas are being opened up by pulsed sources, particularly with the intense epithermal neutron beams, which promise to be several orders of magnitude more intense than can be obtained from a thermal reactor

Neutrons and music: Imaging investigation of ancient wind musical instruments

Science.gov (United States)

Festa, G.; Tardino, G.; Pontecorvo, L.; Mannes, D. C.; Senesi, R.; Gorini, G.; Andreani, C.

2014-10-01

A set of seven musical instruments and two instruments cares from the 'Fondo Antico della Biblioteca del Sacro Convento' in Assisi, Italy, were investigated through neutron and X-ray imaging techniques. Historical and scientific interests around ancient musical instruments motivate an intense research effort for their characterization using non-destructive and non-invasive techniques. X-ray and neutron tomography/radiography were applied to the study of composite material samples containing wood, hide and metals. The study was carried out at the NEUTRA beamline, PSI (Paul Scherrer Institute, Switzerland). Results of the measurements provided new information on the composite and multi-scale structure, such as: the internal structure of the samples, position of added materials like metals, wood fiber displays, deformations, presence of adhesives and their spatial distribution and novel insight about construction methods to guide the instruments' restoration process.

Monte Carlo simulation of neutron scattering instruments

International Nuclear Information System (INIS)

Seeger, P.A.

1995-01-01

A library of Monte Carlo subroutines has been developed for the purpose of design of neutron scattering instruments. Using small-angle scattering as an example, the philosophy and structure of the library are described and the programs are used to compare instruments at continuous wave (CW) and long-pulse spallation source (LPSS) neutron facilities. The Monte Carlo results give a count-rate gain of a factor between 2 and 4 using time-of-flight analysis. This is comparable to scaling arguments based on the ratio of wavelength bandwidth to resolution width

Neutron scattering instrumentation for biology at spallation neutron sources

Energy Technology Data Exchange (ETDEWEB)

Pynn, R. [Los Alamos National Laboratory, NM (United States)

1994-12-31

Conventional wisdom holds that since biological entities are large, they must be studied with cold neutrons, a domain in which reactor sources of neutrons are often supposed to be pre-eminent. In fact, the current generation of pulsed spallation neutron sources, such as LANSCE at Los Alamos and ISIS in the United Kingdom, has demonstrated a capability for small angle scattering (SANS) - a typical cold- neutron application - that was not anticipated five years ago. Although no one has yet built a Laue diffractometer at a pulsed spallation source, calculations show that such an instrument would provide an exceptional capability for protein crystallography at one of the existing high-power spoliation sources. Even more exciting is the prospect of installing such spectrometers either at a next-generation, short-pulse spallation source or at a long-pulse spallation source. A recent Los Alamos study has shown that a one-megawatt, short-pulse source, which is an order of magnitude more powerful than LANSCE, could be built with today`s technology. In Europe, a preconceptual design study for a five-megawatt source is under way. Although such short-pulse sources are likely to be the wave of the future, they may not be necessary for some applications - such as Laue diffraction - which can be performed very well at a long-pulse spoliation source. Recently, it has been argued by Mezei that a facility that combines a short-pulse spallation source similar to LANSCE, with a one-megawatt, long-pulse spallation source would provide a cost-effective solution to the global shortage of neutrons for research. The basis for this assertion as well as the performance of some existing neutron spectrometers at short-pulse sources will be examined in this presentation.

Optimization of virtual source parameters in neutron scattering instrumentation

International Nuclear Information System (INIS)

Habicht, K; Skoulatos, M

2012-01-01

We report on phase-space optimizations for neutron scattering instruments employing horizontal focussing crystal optics. Defining a figure of merit for a generic virtual source configuration we identify a set of optimum instrumental parameters. In order to assess the quality of the instrumental configuration we combine an evolutionary optimization algorithm with the analytical Popovici description using multidimensional Gaussian distributions. The optimum phase-space element which needs to be delivered to the virtual source by preceding neutron optics may be obtained using the same algorithm which is of general interest in instrument design.

Software for simulation and design of neutron scattering instrumentation

DEFF Research Database (Denmark)

Bertelsen, Mads

designed using the software. The Union components uses a new approach to simulation of samples in McStas. The properties of a sample are split into geometrical and material, simplifying user input, and allowing the construction of complicated geometries such as sample environments. Multiple scattering...... from conventional choices. Simulation of neutron scattering instrumentation is used when designing instrumentation, but also to understand instrumental effects on the measured scattering data. The Monte Carlo ray-tracing package McStas is among the most popular, capable of simulating the path of each...... neutron through the instrument using an easy to learn language. The subject of the defended thesis is contributions to the McStas language in the form of the software package guide_bot and the Union components.The guide_bot package simplifies the process of optimizing neutron guides by writing the Mc...

Neutron generator instrumentation at the Department 2350 Neutron Generator Test Facility

International Nuclear Information System (INIS)

Bryant, T.C.; Mowrer, G.R.

1979-06-01

The computer and waveform digitizing capability at the test facility has allowed several changes in the techniques used to test neutron generators. These changes include methods used to calibrate the instrumentation and changes in the operation of the test facility. These changes have increased the efficiency of the test facility as well as increasing both timing and amplitude accuracy of neutron generator waveforms

Backscattering at a pulsed neutron source, the MUSICAL instrument

International Nuclear Information System (INIS)

Alefeld, B.

1995-01-01

In the first part the principles of the neutron backscattering method are described and some simple considerations about the energy resolution and the intensity are presented. A prototype of a backscattering instrument, the first Juelich instrument, is explained in some detail and a representative measurement is shown which was performed on the backscattering instrument IN10 at the ILL in Grenoble. In the second part a backscattering instrument designed for a pulsed neutron source is proposed. It is shown that a rather simple modification, which consists in the replacement of the Doppler drive of the conventional backscattering instrument by a multi silicon monochromator crystal (MUSICAL) leads to a very effective instrument, benefitting from the peak flux of the pulsed source. ((orig.))

Radiochemical and instrumental neutron activation analysis - recent trends

International Nuclear Information System (INIS)

Dams, R.

1990-01-01

Recent trends of radiochemical and instrumental neutron activation analysis are discussed. Novel developments include the application of cyclic and pulsed activation, better energy resolution with hyperpure germanium detectors, and use of pulse processing systems allowing extremely high count rates of very short-lived isotopes. Further development is anticipated in the field of speciation in biological and environmental studies. Radiochemical methods have led to accurate determinations at the ng/g level. A promising future is expected for neutron activation techniques. (orig.)

Design of analytical instrumentation with D-T sealed neutron generators

International Nuclear Information System (INIS)

Qiao Yahua; Wu Jizong; Zheng Weiming; Liu Quanwei; Zhang Min

2008-01-01

Analytical instrumentation with D-T sealed neutron generators source activation, The 14 MeV D-T sealed neutron tube with 10 9 n · s -1 neutron yield is used as generator source. The optimal structure of moderator and shield was achieved by MC computing.The instrumentation's configuration is showed. The instrumentation is made up of the SMY-DT50.8-2.1 sealed neutron tube and the high-voltage power supply system, which center is the sealed neutron generators. 6 cm Pb and 20 cm polythene is chosen as moderator, Pb, polythene and 10 cm boron-PE was chosen as shield .The sample box is far the source from 9 cm, the measurement system were made up of HPGe detector and the sample transforming system. After moderator and shield, the thermal neutron fluence rate at the point of sample is 0.93 × 10 6 n · s -1 cm -2 , which is accorded with design demand, and the laboratory and surroundings reaches the safety standard of the dose levels. (authors)

Measurements with the new PHE neutron survey instrument

International Nuclear Information System (INIS)

Eakins, J.S.; Tanner, R.J.; Hager, L.G.

2014-01-01

A novel design of survey instrument has been developed to accurately estimate ambient dose equivalent from neutrons with energies in the range from thermal to 20 MeV. The device features moderating and attenuating layers to ease measurement of fast and intermediate energy neutrons, combined with guides that channel low-energy neutrons to the single, central detector. A prototype of this device has been constructed and exposed to a set of calibration fields: the resulting measured responses are presented and discussed here, and compared against Monte Carlo data. A simple simulated workplace neutron field has also been developed to test the device. Measured response data have been determined for a prototype design of neutron survey instrument, using facilities at PHE and NPL. In general, the results demonstrated good directional invariance and agreed well with data obtained by Monte Carlo modelling, raising confidence in the accuracy of the response characteristics expected for the device. A simple simulated workplace field has also been developed and characterised, and the performance of the device assessed in it: agreement between measured and modelled results suggests that the device would behave as anticipated in real workplace fields. These performances will be investigated further in the future, as the design makes the transition from a research prototype to a commercially available instrument. (authors)

Development of Interactive Monitoring System for Neutron Scattering Instrument

Energy Technology Data Exchange (ETDEWEB)

So, Ji Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

Neutron scattering instruments in HANARO research reactor have been contributed to various fields of basic science and material engineering. These instruments are open to publics and researchers can apply beam-time and do experiments with instrument scientists. In most cases, these instruments run for several weeks without stopping, and therefore instrument scientist wants to see the instrument status and receive information if the instruments have some problem. This is important for the safety. However, it is very hard to get instrument information outside of instruments. Access from external site is strongly forbidden in the institute due to the network safety, I developed another way to send instrument status information using commercial short messaging service(SMS). In this presentation, detailed features of this system will be shown. As a prototype, this system is being developed for the single instrument: Disk-chopper time-of-flight instruments (DC-TOF). I have successfully developed instruments and operate for several years. This information messaging system can be used for other neutron scattering instruments.

Neutrons and music: Imaging investigation of ancient wind musical instruments

Energy Technology Data Exchange (ETDEWEB)

Festa, G., E-mail: giulia.festa@roma2.infn.it [Università degli Studi di Roma Tor Vergata (Italy); Università degli Studi di Milano-Bicocca (Italy); Consiglio Nazionale delle Ricerche-IPCF, Messina (Italy); Tardino, G. [BauArt Basel, Basel (Switzerland); Pontecorvo, L. [Conservatorio di Cosenza – Cosenza Conservatory (Italy); Mannes, D.C. [Paul Scherrer Institut, Villigen (Switzerland); Senesi, R. [Università degli Studi di Roma Tor Vergata (Italy); Consiglio Nazionale delle Ricerche-IPCF, Messina (Italy); Gorini, G. [Università degli Studi di Milano-Bicocca (Italy); Andreani, C. [Università degli Studi di Roma Tor Vergata (Italy); Consiglio Nazionale delle Ricerche-IPCF, Messina (Italy)

2014-10-01

A set of seven musical instruments and two instruments cares from the ‘Fondo Antico della Biblioteca del Sacro Convento’ in Assisi, Italy, were investigated through neutron and X-ray imaging techniques. Historical and scientific interests around ancient musical instruments motivate an intense research effort for their characterization using non-destructive and non-invasive techniques. X-ray and neutron tomography/radiography were applied to the study of composite material samples containing wood, hide and metals. The study was carried out at the NEUTRA beamline, PSI (Paul Scherrer Institute, Switzerland). Results of the measurements provided new information on the composite and multi-scale structure, such as: the internal structure of the samples, position of added materials like metals, wood fiber displays, deformations, presence of adhesives and their spatial distribution and novel insight about construction methods to guide the instruments’ restoration process.

Neutrons and music: Imaging investigation of ancient wind musical instruments

International Nuclear Information System (INIS)

Festa, G.; Tardino, G.; Pontecorvo, L.; Mannes, D.C.; Senesi, R.; Gorini, G.; Andreani, C.

2014-01-01

A set of seven musical instruments and two instruments cares from the ‘Fondo Antico della Biblioteca del Sacro Convento’ in Assisi, Italy, were investigated through neutron and X-ray imaging techniques. Historical and scientific interests around ancient musical instruments motivate an intense research effort for their characterization using non-destructive and non-invasive techniques. X-ray and neutron tomography/radiography were applied to the study of composite material samples containing wood, hide and metals. The study was carried out at the NEUTRA beamline, PSI (Paul Scherrer Institute, Switzerland). Results of the measurements provided new information on the composite and multi-scale structure, such as: the internal structure of the samples, position of added materials like metals, wood fiber displays, deformations, presence of adhesives and their spatial distribution and novel insight about construction methods to guide the instruments’ restoration process

Flux Gain for Next-Generation Neutron-Scattering Instruments Resulting From Improved Supermirror Performance

International Nuclear Information System (INIS)

Rehm, C.

2001-01-01

Next-generation spallation neutron source facilities will offer instruments with unprecedented capabilities through simultaneous enhancement of source power and usage of advanced optical components. The Spallation Neutron Source (SNS), already under construction at Oak Ridge National Laboratory and scheduled to be completed by 2006, will provide greater than an order of magnitude more effective source flux than current state-of-the-art facilities, including the most advanced research reactors. An additional order of magnitude gain is expected through the use of new optical devices and instrumentation concepts. Many instrument designs require supermirror (SM) neutron guides with very high critical angles for total reflection. In this contribution, they discuss how the performance of modern neutron scattering instruments depends on the efficiency of these supermirrors. They outline ideas for enhancing the performance of the SM coatings, particularly for improving the reflectivity at the position of the critical wave vector transfer. A simulation program has been developed which allows different approaches for SM designs to be studied. Possible instrument performance gains are calculated for the example of the SNS reflectometer

A high-sensitivity neutron counter and waste-drum counting with the high-sensitivity neutron instrument

International Nuclear Information System (INIS)

Hankins, D.E.; Thorngate, J.H.

1993-04-01

At Lawrence Livermore National Laboratory (LLNL), a highly sensitive neutron counter was developed that can detect and accurately measure the neutrons from small quantities of plutonium or from other low-level neutron sources. This neutron counter was originally designed to survey waste containers leaving the Plutonium Facility. However, it has proven to be useful in other research applications requiring a high-sensitivity neutron instrument

A study on cigarette tobacco by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Md Soot Haji Ahmad; Tey Nsan Yen

1987-01-01

The concentration of 25 elements in cigarette tobacco of popular brands locally marketed were determined using instrumental neutron activation analysis. These elements are: Al, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Mg, Mn, Na, Rb, Sb, Sc, Se, Sr, Th, and Zn. Comparison of the element contents to the reported cigarette tobacco of Egypt, Iran and Turkey was also done. (author)

Development of network communication function for digitalized neutron flux monitoring instrument

International Nuclear Information System (INIS)

Li Kai; Zhang Liangju; Chen Xiaojun; Li Baoxiang

2002-01-01

It is essential for a digitalized Neutron Flux Monitoring Instrument to communicate with other parts of Instrumentation and Control System in a network environment, and it is fairly different from the case of traditional analogue nuclear instrumentation. How to satisfy all the requirements of different network structure and communication protocol, which might be adopted in different target nuclear power plant, is a key issue in the design and development of a digitalized neutron flux monitoring instrument. The author describes the overall communication scheme, mainly discusses the design idea and the requirements of the communication interfaces and the implementation of the RS-485 interface as an example of the digitalized neutron flux monitoring instrument, which is under development in the institute

Larmor-precession based neutron scattering instrumentation

International Nuclear Information System (INIS)

Ioffe, Alexander

2009-01-01

The Larmor precession of the neutron spin in a magnetic field allows the attachment of a Larmor clock to every neutron. Such Larmor labelling opens the possibility for the development of unusual neutron scattering techniques, where the energy (momentum) resolution does not require the initial and final states to be well selected. This principally allows for achievement of very high energy (momentum) resolution that is not feasible at all with conventional neutron scattering techniques, because the required neutron beam monochromatization (collimation) will result in intolerable intensity losses. Such decoupling of resolution and collimation allows, for example, for a significant increase in the luminosity of small-angle scattering or high-resolution diffractometers; the fact that opens new perspectives for their implementation at middle flux neutron sources. Different kinds of Larmor clock-based instrumentation, particularly two alternative NSE techniques using rotating and time-gradient magnetic field arrangements, which can be considered as inexpensive and affordable alternatives to present day NSE techniques, will be discussed and results of simulations and first experiments will be presented. (author)

Radiation protection commissioning of neutron beam instruments at the OPAL research reactor

International Nuclear Information System (INIS)

Parkes, Alison; Saratsopoulos, John; Deura, Michael; Kenny, Pat

2008-01-01

The neutron beam facilities at the 20 MW OPAL Research Reactor were commissioned in 2007 and 2008. The initial suite of eight neutron beam instruments on two thermal neutron guides, two cold neutron guides and one thermal beam port located at the reactor face, together with their associated shielding were progressively installed and commissioned according to their individual project plans. Radiation surveys were systematically conducted as reactor power was raised in a step-wise manner to 20 MW in order to validate instrument shielding design and performance. The performance of each neutron guide was assessed by neutron energy spectrum and flux measurements. The activation of beam line components, decay times assessments and access procedures for Bragg Institute beam instrument scientists were established. The multiple configurations for each instrument and the influence of operating more than one instrument or beamline simultaneously were also tested. Areas of interest were the shielding around the secondary shutters, guide shield and bunker shield interfaces and monochromator doors. The shielding performance, safety interlock checks, improvements, radiation exposures and related radiation protection challenges are discussed. This paper discusses the health physics experience of commissioning the OPAL Research Reactor neutron beam facilities and describes health physics results, actions taken and lessons learned during commissioning. (author)

New sources and instrumentation for neutron science

International Nuclear Information System (INIS)

Gil, Alina

2011-01-01

Neutron-scattering research has a lot to do with our everyday lives. Things like medicine, food, electronics, cars and airplanes have all been improved by neutron-scattering research. Neutron research also helps scientists improve materials used in a multitude of different products, such as high-temperature superconductors, powerful lightweight magnets, stronger, lighter plastic products etc. Neutron scattering is one of the most effective ways to obtain information on both, the structure and the dynamics of condensed matter. Most of the world's neutron sources were built decades ago, and although the uses and demand for neutrons have increased throughout the years, few new sources have been built. The new construction, accelerator-based neutron source, the spallation source will provide the most intense pulsed neutron beams in the world for scientific research and industrial development. In this paper it will be described what neutrons are and what unique properties make them useful for science, how spallation source is designed to produce neutron beams and the experimental instruments that will use those beams. Finally, it will be described how past neutron research has affected our everyday lives and what we might expect from the most exciting future applications.

New sources and instrumentation for neutron science

Energy Technology Data Exchange (ETDEWEB)

Gil, Alina, E-mail: a.gil@ajd.czest.pl [Faculty of Mathematical and Natural Sciences, JD University, Al. Armii Krajowej 13/15, 42-200 Czestochowa (Poland)

2011-04-01

Neutron-scattering research has a lot to do with our everyday lives. Things like medicine, food, electronics, cars and airplanes have all been improved by neutron-scattering research. Neutron research also helps scientists improve materials used in a multitude of different products, such as high-temperature superconductors, powerful lightweight magnets, stronger, lighter plastic products etc. Neutron scattering is one of the most effective ways to obtain information on both, the structure and the dynamics of condensed matter. Most of the world's neutron sources were built decades ago, and although the uses and demand for neutrons have increased throughout the years, few new sources have been built. The new construction, accelerator-based neutron source, the spallation source will provide the most intense pulsed neutron beams in the world for scientific research and industrial development. In this paper it will be described what neutrons are and what unique properties make them useful for science, how spallation source is designed to produce neutron beams and the experimental instruments that will use those beams. Finally, it will be described how past neutron research has affected our everyday lives and what we might expect from the most exciting future applications.

Comparison of instrumental neutron activation analysis and instrumental charged-particle activation analysis for determining of Zn-68 abundance

International Nuclear Information System (INIS)

Rafii, H.; Mirzaei, M.; Aslani, G.R.; Kamali-Dehghan, M.; Rajamand, A-A.; Rahiminejad, A.; Mirzajani, N.; Sardari, D.; Shahabi, I.; Majidi, F.

2004-01-01

Gallium-67 has found important applications in nuclear medicine since last decades. The bombardment of enriched zinc-68 by proton beams in cyclotron is the most suitable method for the carrier-free production of this radionuclide. Any traces and isotopic impurities of the target cause serious radiological hazards because of their associated induced radioactivities. Trace analysis and Zn-68 content determination of the target material before any bombardment and chemical separation provide a valuable assessment of desired product. The elemental abundance evaluation of enriched isotopes is generally carried out by inductively coupled plasma-mass spectrometry method, ICP-Ms Instrumental neutron activation analysis and instrumental charged particle activation analysis. International neutron activation analysis and instrumental charged- particle activation analysis, looks be an alternative nuclear method for determining the abundance evaluation of enriched Zn-68 enrichment in two different samples has been studied by mean of international neutron activation analysis and instrumental charged- particle activation analysis . One sample was purchased from a French company, cortecnet, and the other was separated by an electromagnetic system in the Ions source department of our center, NRCAM. The neutron or proton irradiation was took place respectively in miniature neutron source reactor of Esfahan by flux of (1 to 5) 10 11 n/cm 2 .sec for 30 min and in Cyclon30 by 19 MeV proton beams of 100μA current for 12 min. The produced radioactivity was measured by HpGe detector for determination of trace impurities and evaluation of Zn-68 content in the samples. The result shows a good agreement with the reported ones by their producers and their low derivation of about ± indicates that the international neutron activation analysis and instrumental charged- particle activation analysis are relatively precise and rapid and each one can be used as a supplemental method for analyzing

LUPIN, a new instrument for pulsed neutron fields

Energy Technology Data Exchange (ETDEWEB)

Caresana, M. [Politecnico di Milano, Department of Energy, Via Ponzio 34/3, 20133 Milan (Italy); Ferrarini, M. [Politecnico di Milano, Department of Energy, Via Ponzio 34/3, 20133 Milan (Italy); CNAO, Via Privata Campeggi, 27100 Pavia (Italy); Manessi, G.P., E-mail: giacomo.paolo.manessi@cern.ch [CERN, 1211 Geneva 23 (Switzerland); University of Liverpool, Department of Physics, L69 7ZE Liverpool (United Kingdom); Silari, M. [CERN, 1211 Geneva 23 (Switzerland); Varoli, V. [Politecnico di Milano, Department of Energy, Via Ponzio 34/3, 20133 Milan (Italy)

2013-06-01

A number of studies focused in the last decades on the development of survey meters to be used in pulsed radiation fields. This is a topic attracting widespread interest for applications such as radiation protection and beam diagnostics in accelerators. This paper describes a new instrument specifically conceived for applications in pulsed neutron fields (PNF). The detector, called LUPIN, is a rem counter type instrument consisting of a {sup 3}He proportional counter placed inside a spherical moderator. It works in current mode with a front-end electronics consisting of a current–voltage logarithmic amplifier, whose output signal is acquired with an ADC and processed on a PC. This alternative signal processing allows the instrument to be used in PNF without being affected by saturation effects. Moreover, it has a measurement capability ranging over many orders of burst intensity. Despite the fact that it works in current mode, it can measure a single neutron interaction. The LUPIN was first calibrated in CERN's calibration laboratory with a PuBe source. Measurements were carried out under various experimental conditions at the Helmholtz-Zentrum in Berlin, in the stray field at various locations of the CERN Proton Synchrotron complex and around a radiotherapy linear accelerator at the S. Raffaele hospital in Milan. The detector can withstand single bursts with values of H⁎(10) up to 16 nSv/burst without showing any saturation effect. It efficiently works in pulsed stray fields, where a conventional rem-counter underestimates by a factor of 2. It is also able to reject the very intense and pulsed photon contribution that often accompanies the neutron field with good reliability. -- Highlights: ► LUPIN is a new detector specifically conceived to work in neutron pulsed fields. ► The detector is a rem counter type instrument working in current mode. ► The performances of the detectors were studied under various experimental conditions. ► The detector

Neutron Instrumentation and Neutron Investigation of Archaeometallurgical Arms and Armours

DEFF Research Database (Denmark)

Fedrigo, Anna

Neutron scattering, once a technique that was the preserve of physics and chemistry, has grown to be applied in a much broader range of fields, spanning engineering, archaeology, life-science, and sustainable-energy applications. The present work focuses on two topics: first, the instrument desig...

Neutron and synchrotron radiation for condensed matter studies. Volume 1: theory, instruments and methods

International Nuclear Information System (INIS)

Baruchel, J.; Hodeau, J.L.; Lehmann, M.S.; Regnard, J.R.; Schlenker, C.

1993-01-01

This book provides the basic information required by a research scientist wishing to undertake studies using neutrons or synchrotron radiation at a Large Facility. These lecture notes result from 'HERCULES', a course that has been held in Grenoble since 1991 to train young scientists in these fields. They cover the production of neutrons and synchrotron radiation and describe all aspects of instrumentation. In addition, this work outlines the basics of the various fields of research pursued at these Large Facilities. It consists of a series of chapters written by experts in the particular fields. While following a progression and constituting a lecture course on neutron and x-ray scattering, these chapters can also be read independently. This first volume will be followed by two further volumes concerned with the applications to solid state physics and chemistry, and to biology and soft condensed matter properties

Intercomparison of radiation protection instrumentation in a pulsed neutron field

Energy Technology Data Exchange (ETDEWEB)

Caresana, M., E-mail: marco.caresana@polimi.it [Politecnico di Milano, CESNEF, Dipartimento di Energia, via Ponzio 34/3, 20133 Milano (Italy); Denker, A. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Esposito, A. [IFNF-LNF, FISMEL, via E. Fermi 40, 00044 Frascati (Italy); Ferrarini, M. [CNAO, Via Privata Campeggi, 27100 Pavia (Italy); Golnik, N. [Institute of Metrology and Biomedical Engineering, Warsaw University of Technology, Sw. A. Boboli 8, 02-525 Warsaw (Poland); Hohmann, E. [Paul Scherrer Institut (PSI), Radiation Metrology Section, CH-5232 Villigen PSI (Switzerland); Leuschner, A. [Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22603 Hamburg (Germany); Luszik-Bhadra, M. [Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig (Germany); Manessi, G. [CERN, 1211 Geneva 23 (Switzerland); University of Liverpool, Department of Physics, L69 7ZE Liverpool (United Kingdom); Mayer, S. [Paul Scherrer Institut (PSI), Radiation Metrology Section, CH-5232 Villigen PSI (Switzerland); Ott, K. [Helmholtz-Zentrum Berlin, BESSYII, Albert-Einstein-Str.15, 12489 Berlin (Germany); Röhrich, J. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Silari, M. [CERN, 1211 Geneva 23 (Switzerland); Trompier, F. [Institute for Radiological Protection and Nuclear Safety, F-92262 Fontenay aux Roses (France); Volnhals, M.; Wielunski, M. [Helmholtz Zentrum München, Ingolstädter Landstr. 1, D-85764 Neuherberg (Germany)

2014-02-11

In the framework of the EURADOS working group 11, an intercomparison of active neutron survey meters was performed in a pulsed neutron field (PNF). The aim of the exercise was to evaluate the performances of various neutron instruments, including commercially available rem-counters, personal dosemeters and instrument prototypes. The measurements took place at the cyclotron of the Helmholtz-Zentrum Berlin für Materialien und Energie GmbH. The cyclotron is routinely used for proton therapy of ocular tumours, but an experimental area is also available. For the therapy the machine accelerates protons to 68 MeV. The interaction of the proton beam with a thick tungsten target produces a neutron field with energy up to about 60 MeV. One interesting feature of the cyclotron is that the beam can be delivered in bursts, with the possibility to modify in a simple and flexible way the burst length and the ion current. Through this possibility one can obtain radiation bursts of variable duration and intensity. All instruments were placed in a reference position and irradiated with neutrons delivered in bursts of different intensity. The analysis of the instrument response as a function of the burst charge (the total electric charge of the protons in the burst shot onto the tungsten target) permitted to assess for each device the dose underestimation due to the time structure of the radiation field. The personal neutron dosemeters were exposed on a standard PMMA slab phantom and the response linearity was evaluated.

Neutron cross section standards and instrumentation: Annual report

International Nuclear Information System (INIS)

1987-01-01

This annual report from the National Bureau of Standards contains a summary of the results of the Neutron Cross Section Standards and Instrumentation Program. The technical measurements for the past year are given along with the proposed program and budget needs for the next three years. The neutron standards measurements have concentrated on the most important 235 U(n,f) cross section in the thermal to 20 MeV energy range along with the development of neutron detectors required for these measurements. The NBS measurements have made a significant contribution to the improvement in the understanding of this reaction. Measurements were performed with numerous neutron detectors at overlapping energies and at different neutron sources in order to reduce the systematic errors to achieve the required accuracy in this important neutron standard. Significant progress was also made in the development of a detector to utilize the 3 He(n,p) reaction as a standard in the eV to MeV energy region. Improvements in data acquisition systems as well as additional studies of advanced neutron sources were accomplished. Contacts with private industry were maintained and coordination of the neutron standards evaluation was continued. The report also includes biographical listings of the research staff along with copies of a few of our recent publications. 13 figs., 1 tab

Portable neutron and gamma-radiation instruments

International Nuclear Information System (INIS)

Murray, W.S.; Butterfield, K.B.

1990-01-01

This paper reports on the design and building of a smart neutron and gamma-radiation detection systems with embedded microprocessors programmed in the FORTH language. These portable instruments can be battery-powered and can provide many analysis functions not available in most radiation detectors. Local operation of the instruments is menu-driven through a graphics liquid crystal display and hex keypad; remote operation is through a serial communications link. While some instruments simply count particles, others determine the energy of the radiation as well as the intensity. The functions the authors have provided include absolute source-strength determination. Feynmann variance analysis, sequential-probability ratio test, and time-history recording

Instrumental Neutron Activation Analysis and Multivariate Statistics for Pottery Provenance

Science.gov (United States)

Glascock, M. D.; Neff, H.; Vaughn, K. J.

2004-06-01

The application of instrumental neutron activation analysis and multivariate statistics to archaeological studies of ceramics and clays is described. A small pottery data set from the Nasca culture in southern Peru is presented for illustration.

Instrumental Neutron Activation Analysis and Multivariate Statistics for Pottery Provenance

International Nuclear Information System (INIS)

Glascock, M. D.; Neff, H.; Vaughn, K. J.

2004-01-01

The application of instrumental neutron activation analysis and multivariate statistics to archaeological studies of ceramics and clays is described. A small pottery data set from the Nasca culture in southern Peru is presented for illustration.

Instrumental Neutron Activation Analysis and Multivariate Statistics for Pottery Provenance

Energy Technology Data Exchange (ETDEWEB)

Glascock, M. D.; Neff, H. [University of Missouri, Research Reactor Center (United States); Vaughn, K. J. [Pacific Lutheran University, Department of Anthropology (United States)

2004-06-15

The application of instrumental neutron activation analysis and multivariate statistics to archaeological studies of ceramics and clays is described. A small pottery data set from the Nasca culture in southern Peru is presented for illustration.

The use of neutron radiography and microdensitometry in the study of instrumental effectiveness on dental tissue in the process of mineralization

International Nuclear Information System (INIS)

Vulcain, J.M.; Tamisier, J.; Espie, J.H.; Masse, R.; Laporte, A.

1983-01-01

In this study, neutron-radiography is used as a non-destructive method of exposing the peripheral part of the root canal which, in the course of endodontic treatment, is to be removed by root therapy instruments. Samples are treated with an agent of contrast with high screen power for neutrons: gadolinium which is used in the form of a citrate solution, it slowly diffuses through non-mineralized structures and settles like the other rare earths on the interface of mineralized tissues and of those in the process of mineralization, in this case, dentin and predentin. This mechanism is on occasion controlled by the richness of proteoglycans in this tissue. Once the samples are saturated, a neutron-radiographic image is made, then analyzed by microdensitometry so as to obtain a quantitative parameter. After instrumentation of the samples, a new neutron-radiographic image, and a new microdensitometric analysis are made. The results thus obtained make it possible to quantify the effectiveness of the various instruments available for endodontic treatments. (Auth.)

Salvinia auriculata: Aquatic bioindicator studied by instrumental neutron activation analysis (INAA)

Energy Technology Data Exchange (ETDEWEB)

Ferreira Soares, Daniel Cristian; Figueiredo de Oliveira, Ester [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), Avenida Antonio Carlos, 6627 Pampulha, CEP 30123-970 Belo Horizonte, Minas Gerais (Brazil); Fatima Silva, Gracia Divina de; Duarte, Lucienir Pains [Departamento de Quimica, ICEx, Nucleo de estudos de Plantas Medicinais (NEPLAM), Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627 Pampulha, 31270-901 Belo Horizonte, Minas Gerais (Brazil); Pott, Vali Joana [Empresa Brasileira de Agropecuaria (EMBRAPA), BR 262 km 4, Caixa Postal 154, CEP 79002-970 Campo Grande, Mato Grosso do Sul (Brazil); Vieira Filho, Sidney Augusto [Escola de Farmacia, DEFAR, Universidade Federal de Ouro Preto, Rua Costa Sena, 171, CEP 35400-000 Ouro Preto, Minas Gerais (Brazil)], E-mail: bibo@ef.ufop.br

2008-05-15

Through instrumental neutron activation analysis (INAA) the elemental chemical composition of Salvinia auriculata and Ouro Preto city public water was determined. Elements Ce, Th, Cr, Hf, Sb, Sc, Rb, Fe, Zn, Co, Au, La and Br were quantified. High chromium concentration was determined in this plant. But, chromium was determined only in low concentrations in the water. The results indicate the great capacity of this plant to absorb and accumulate inorganic elements.

Neutron beam-line shield design for the protein crystallography instrument at the Lujan Center

International Nuclear Information System (INIS)

Russell, G.J.; Pitcher, E.J.; Muhrer, G.; Ferguson, P.D.

2001-01-01

We have developed a very useful methodology for calculating absolute total (neutron plus gamma-ray) dose equivalent rates for use in the design of neutron beam line shields at a spallation neutron source. We have applied this technique to the design of beam line shields for several new materials science instruments being built at the Manuel Lujan Jr. Neutron Scattering Center. These instruments have a variety of collimation systems and different beam line shielding issues. We show here some specific beam line shield designs for the Protein Crystallography Instrument. (author)

Influence of instrument design on neutron lifetime measurements

International Nuclear Information System (INIS)

Youmans, A.H.; Hopkinson, E.C.

1975-01-01

Commercially available logging services provide a measurement of the lifetime of thermal neutrons in formations adjacent to a borehole. This lifetime provides a measure of the macroscopic thermal neutron-capture cross-section Σ of the formation, which in turn is functionally related to the abundance and constituency of the rock matrix and contained fluids. Because the measurement is extremely sensitive to an abundance of trace elements like boron and gadolinium, it is very difficult to find rock formations with an accurately known value of Σ, which is required for the accuracy of the measuring system to be experimentally tested. Various theoretical studies published suggest that errors in the determination of Σ may occur because of the influence of borehole parameters and the effects of neutron diffusion. Experimental results are reported that demonstrate that the design of the instrument is crucial to the validity of any theoretical treatment of the subject. The influence of neutron diffusion and borehole effects can be overcome by optimal selection of spacing and shielding parameters

Instrumental neutron activation analysis - a routine method

International Nuclear Information System (INIS)

Bruin, M. de.

1983-01-01

This thesis describes the way in which at IRI instrumental neutron activation analysis (INAA) has been developed into an automated system for routine analysis. The basis of this work are 20 publications describing the development of INAA since 1968. (Auth.)

A Workshop on Methods for Neutron Scattering Instrument Design. Introduction and Summary

International Nuclear Information System (INIS)

Hjelm, Rex P.

1996-09-01

The future of neutron and x-ray scattering instrument development and international cooperation was the focus of the workshop on ''Methods for Neutron Scattering Instrument Design'' September 23-25 at the E.O. Lawrence Berkeley National Laboratory. These proceedings are a collection of a portion of the invited and contributed presentations

Neutron scattering instrumentation. A guide to future directions

International Nuclear Information System (INIS)

Crawford, R.K.

2001-01-01

Many of the neutron scattering instruments being designed or built now are the first generation of pulsed source instruments to provide nearly optimal scattering angle coverage with good spatial resolution in a single setting of the instrument while making full use of modern optics to maximize the useful flux on the sample. Spectacular gains have resulted from such optimization, but in most of these cases there is little room for further large improvements. However, other types of pulsed source instruments are currently less well optimized, and there is room for significant improvements in these types of pulsed source instruments. Several examples will illustrate these points. In the longer term, we can expect source strengths to continue to increase, but only slowly. However, we can expect new science and new ways of doing experiments to emerge. Many of these changes will be driven by enhancements in sample environment capabilities leading to more innovative sample conditions and to efficient parametric studies. Kinetic studies and parametric studies will take on much greater roles with the high data rates now available. Implications of these trends will be discussed. (author)

The neutron instrument Monte Carlo library MCLIB: Recent developments

International Nuclear Information System (INIS)

Seeger, P.A.; Daemen, L.L.; Hjelm, R.P. Jr.; Thelliez, T.G.

1998-01-01

A brief review is given of the developments since the ICANS-XIII meeting made in the neutron instrument design codes using the Monte Carlo library MCLIB. Much of the effort has been to assure that the library and the executing code MC RUN connect efficiently with the World Wide Web application MC-WEB as part of the Los Alamos Neutron Instrument Simulation Package (NISP). Since one of the most important features of MCLIB is its open structure and capability to incorporate any possible neutron transport or scattering algorithm, this document describes the current procedure that would be used by an outside user to add a feature to MCLIB. Details of the calling sequence of the core subroutine OPERATE are discussed, and questions of style are considered and additional guidelines given. Suggestions for standardization are solicited, as well as code for new algorithms

Neutron diffraction instruments at the BR2 reactor and their use in the study of crystal and magnetic structures

International Nuclear Information System (INIS)

Legrand, E.

1977-01-01

The study of structural properties of condensed matted is frequently performed by means of methods based on X-ray, electron or neutron scattering. In many particular cases, the latter technique offers definite advantages which are mainly based on the following characteristics of neutron-matter interaction: The large penetration depth for neutrons in matter (with the exception of a few elements), which allow the study of large samples and the use of wavelengths from 0.5 to 5A, and even to 10 A; the absence of an atomic form factor; the irregular dependence of the scattering length for the different elements as a function of their atomic number; the large cross section for magnetic scattering; the energy of thermal neutrons which allows the direct measuremtment of the enrgy exchange between the neutrons and the scatterer. Three of the four neutron diffraction instruments for solid state research, installed at the BR2 reactor, are described in detail. (author)

Study of neutron spectrometers for ITER

Energy Technology Data Exchange (ETDEWEB)

Kaellne, Jan

2005-11-15

A review is presented of the developments in the field of neutron emission spectrometry (NES) which is of relevance for identifying the role of NES diagnostics on ITER and selecting suitable instrumentation. Neutron spectrometers will be part of the ITER neutron diagnostic complement and this study makes a special effort to examine which performance characteristics the spectrometers should possess to provide the best burning plasma diagnostic information together with neutron cameras and neutron yield monitors. The performance of NES diagnostics is coupled to how much interface space can be provided which has lead to an interest to find compact instruments and their NES capabilities. This study assesses all known spectrometer types of potential interest for ITER and makes a ranking of their performance (as demonstrated or projected), which, in turn, are compared with ITER measurement requirements as a reference; the ratio of diagnostic performance to interface cost for different spectrometers is also discussed for different spectrometer types. The overall result of the study is an assessment of which diagnostic functions neutron measurements can provide in burning plasma fusion experiments on ITER and the role that NES can play depending on the category of instrument installed. Of special note is the result that much higher quality diagnostic information can be obtained from neutron measurements with total yield monitors, profile flux cameras and spectrometers when the synergy in the data is considered in the analysis and interpretation.

Design of a novel instrument for active neutron interrogation of artillery shells.

Science.gov (United States)

Bélanger-Champagne, Camille; Vainionpää, Hannes; Peura, Pauli; Toivonen, Harri; Eerola, Paula; Dendooven, Peter

2017-01-01

The most common explosives can be uniquely identified by measuring the elemental H/N ratio with a precision better than 10%. Monte Carlo simulations were used to design two variants of a new prompt gamma neutron activation instrument that can achieve this precision. The instrument features an intense pulsed neutron generator with precise timing. Measuring the hydrogen peak from the target explosive is especially challenging because the instrument itself contains hydrogen, which is needed for neutron moderation and shielding. By iterative design optimization, the fraction of the hydrogen peak counts coming from the explosive under interrogation increased from [Formula: see text]% to [Formula: see text]% (statistical only) for the benchmark design. In the optimized design variants, the hydrogen signal from a high-explosive shell can be measured to a statistics-only precision better than 1% in less than 30 minutes for an average neutron production yield of 109 n/s.

Monte Carlo simulation of neutron scattering instruments

International Nuclear Information System (INIS)

Seeger, P.A.; Daemen, L.L.; Hjelm, R.P. Jr.

1998-01-01

A code package consisting of the Monte Carlo Library MCLIB, the executing code MC RUN, the web application MC Web, and various ancillary codes is proposed as an open standard for simulation of neutron scattering instruments. The architecture of the package includes structures to define surfaces, regions, and optical elements contained in regions. A particle is defined by its vector position and velocity, its time of flight, its mass and charge, and a polarization vector. The MC RUN code handles neutron transport and bookkeeping, while the action on the neutron within any region is computed using algorithms that may be deterministic, probabilistic, or a combination. Complete versatility is possible because the existing library may be supplemented by any procedures a user is able to code. Some examples are shown

Design of a novel instrument for active neutron interrogation of artillery shells.

Directory of Open Access Journals (Sweden)

Camille Bélanger-Champagne

Full Text Available The most common explosives can be uniquely identified by measuring the elemental H/N ratio with a precision better than 10%. Monte Carlo simulations were used to design two variants of a new prompt gamma neutron activation instrument that can achieve this precision. The instrument features an intense pulsed neutron generator with precise timing. Measuring the hydrogen peak from the target explosive is especially challenging because the instrument itself contains hydrogen, which is needed for neutron moderation and shielding. By iterative design optimization, the fraction of the hydrogen peak counts coming from the explosive under interrogation increased from [Formula: see text]% to [Formula: see text]% (statistical only for the benchmark design. In the optimized design variants, the hydrogen signal from a high-explosive shell can be measured to a statistics-only precision better than 1% in less than 30 minutes for an average neutron production yield of 109 n/s.

Evaluation of the current fast neutron flux monitoring instrumentation applied to LFR demonstrator ALFRED. Capabilities and limitations

International Nuclear Information System (INIS)

Lepore, Luigi; Remetti, Romolo; Cappelli, Mauro

2015-01-01

Among Gen IV projects for future nuclear power plants, Lead Fast Reactors (LFR) seem to be a very interesting solution due to their benefits in terms of fuel cycle, coolant-safety and waste management. The novelty of the matter causes some open issues about coolant chemical aspect, structural aspects, monitoring instrumentation, etc. Particularly hard neutron flux spectra would make traditional neutron instrumentation unfit to all reactor conditions, i.e. source, intermediate, and power range. Identification of new models of nuclear instrumentation specialized for LFR neutron flux monitoring asks for an accurate evaluation of the environment the sensor will work in. In this study, thermal-hydraulics and chemical conditions for LFR core environment will be assumed, as the neutron flux will be studied extensively by means of the Monte Carlo transport code MCNPX. The core coolant’s high temperature drastically reduces the candidate instrumentation, because only some kind of fission chambers and Self Powered Neutron Detectors can be operated in such an environment. This work aims to evaluate the capabilities of the available instrumentation (usually designed for Sodium Fast Reactors, SFRs) when exposed to the neutron spectrum derived from ALFRED, a pool-type small-power LFR project to demonstrate the feasibility of this technology into the European framework. This paper shows that such instruments do follow the power evolution, but they are not completely suitable to detect the whole range of reactor power. Some improvements are then possible in order to increase the signal-to-noise ratio, by optimizing each instrument in the range of reactor power, such to get the best solution. Some new detector designs are here proposed, and the possibilities for prototyping and testing by means of a fast reactor investigated. (author)

Use of ultracold neutrons for condensed-matter studies

Energy Technology Data Exchange (ETDEWEB)

Michaudon, A.

1997-05-01

Ultracold neutrons have such low velocities that they are reflected by most materials at all incident angles and can be stored in material bottles for long periods of time during which their intrinsic properties can be studied in great detail. These features have been mainly used for fundamental-physics studies including the detection of a possible neutron electric dipole moment and the precise determination of neutron-decay properties. Ultracold neutrons can also play a role in condensed-matter studies with the help of high-resolution spectrometers that use gravity as a strongly dispersive medium for low-velocity neutrons. Such studies have so far been limited by the low intensity of existing ultracold-neutron sources but could be reconsidered with more intense sources, which are now envisaged. This report provides a broad survey of the properties of ultracold neutrons (including their reflectivity by different types of samples), of ultracold-neutron spectrometers that are compared with other high-resolution instruments, of results obtained in the field of condensed matter with these instruments, and of neutron microscopes. All these subjects are illustrated by numerous examples.

Use of ultracold neutrons for condensed-matter studies

International Nuclear Information System (INIS)

Michaudon, A.

1997-05-01

Ultracold neutrons have such low velocities that they are reflected by most materials at all incident angles and can be stored in material bottles for long periods of time during which their intrinsic properties can be studied in great detail. These features have been mainly used for fundamental-physics studies including the detection of a possible neutron electric dipole moment and the precise determination of neutron-decay properties. Ultracold neutrons can also play a role in condensed-matter studies with the help of high-resolution spectrometers that use gravity as a strongly dispersive medium for low-velocity neutrons. Such studies have so far been limited by the low intensity of existing ultracold-neutron sources but could be reconsidered with more intense sources, which are now envisaged. This report provides a broad survey of the properties of ultracold neutrons (including their reflectivity by different types of samples), of ultracold-neutron spectrometers that are compared with other high-resolution instruments, of results obtained in the field of condensed matter with these instruments, and of neutron microscopes. All these subjects are illustrated by numerous examples

The determination of some impurities in zirconium metal by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Eddy, B.T.; Pearton, D.C.G.; Watterson, J.J.

1976-01-01

This report describes the work done on the development of an instrumental neutron-activation method for the analysis of impurities in reactor-grade zirconium. Nine samples were analysed, and the results were compared with those obtained by other techniques. No statistically significant differences were observed for ten of the twelve elements that could possibly be determined by instrumental neutron-activation analysis. Cadmium cannot be determined at the 0,5 p.p.m. level, and there is doubt about the comparative values recorded for aluminium. The precision of the measurement by direct instrumental neutron-activation analysis ranges from 1,4 per cent for tungsten to 17 per cent for chromium [af

Monte Carlo simulations of neutron-scattering instruments using McStas

DEFF Research Database (Denmark)

Nielsen, K.; Lefmann, K.

2000-01-01

Monte Carlo simulations have become an essential tool for improving the performance of neutron-scattering instruments, since the level of sophistication in the design of instruments is defeating purely analytical methods. The program McStas, being developed at Rise National Laboratory, includes...

Materials and Life Science Experimental Facility (MLF at the Japan Proton Accelerator Research Complex II: Neutron Scattering Instruments

Directory of Open Access Journals (Sweden)

Kenji Nakajima

2017-11-01

Full Text Available The neutron instruments suite, installed at the spallation neutron source of the Materials and Life Science Experimental Facility (MLF at the Japan Proton Accelerator Research Complex (J-PARC, is reviewed. MLF has 23 neutron beam ports and 21 instruments are in operation for user programs or are under commissioning. A unique and challenging instrumental suite in MLF has been realized via combination of a high-performance neutron source, optimized for neutron scattering, and unique instruments using cutting-edge technologies. All instruments are/will serve in world-leading investigations in a broad range of fields, from fundamental physics to industrial applications. In this review, overviews, characteristic features, and typical applications of the individual instruments are mentioned.

New developments in the McStas neutron instrument simulation package

International Nuclear Information System (INIS)

Willendrup, P K; Knudsen, E B; Klinkby, E; Nielsen, T; Farhi, E; Filges, U; Lefmann, K

2014-01-01

The McStas neutron ray-tracing software package is a versatile tool for building accurate simulators of neutron scattering instruments at reactors, short- and long-pulsed spallation sources such as the European Spallation Source. McStas is extensively used for design and optimization of instruments, virtual experiments, data analysis and user training. McStas was founded as a scientific, open-source collaborative code in 1997. This contribution presents the project at its current state and gives an overview of the main new developments in McStas 2.0 (December 2012) and McStas 2.1 (expected fall 2013), including many new components, component parameter uniformisation, partial loss of backward compatibility, updated source brilliance descriptions, developments toward new tools and user interfaces, web interfaces and a new method for estimating beam losses and background from neutron optics.

Instrumentation with polarized neutrons

International Nuclear Information System (INIS)

Boeni, P.; Muenzer, W.; Ostermann, A.

2009-01-01

Neutron scattering with polarization analysis is an indispensable tool for the investigation of novel materials exhibiting electronic, magnetic, and orbital degrees of freedom. In addition, polarized neutrons are necessary for neutron spin precession techniques that path the way to obtain extremely high resolution in space and time. Last but not least, polarized neutrons are being used for fundamental studies as well as very recently for neutron imaging. Many years ago, neutron beam lines were simply adapted for polarized beam applications by adding polarizing elements leading usually to unacceptable losses in neutron intensity. Recently, an increasing number of beam lines are designed such that an optimum use of polarized neutrons is facilitated. In addition, marked progress has been obtained in the technology of 3 He polarizers and the reflectivity of large-m supermirrors. Therefore, if properly designed, only factors of approximately 2-3 in neutron intensity are lost. It is shown that S-benders provide neutron beams with an almost wavelength independent polarization. Using twin cavities, polarized beams with a homogeneous phase space and P>0.99 can be produced without significantly sacrificing intensity. It is argued that elliptic guides, which are coated with large m polarizing supermirrors, provide the highest flux.

Tailored instrumentation for long-pulse neutron spallation sources

Czech Academy of Sciences Publication Activity Database

Schober, H.; Farhi, E.; Mezei, F.; Allenspach, P.; Andersen, K.; Bentley, P. M.; Christiansen, P.; Cubitt, B.; Heenan, R. K.; Kulda, J.; Langan, P.; Lefmann, K.; Lieutenant, K.; Monkenbusch, M.; Willendrup, P.; Šaroun, Jan; Tindemans, P.; Zsigmond, G.

2008-01-01

Roč. 589, č. 1 (2008), s. 34-46 ISSN 0168-9002 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutron scattering * instrument simulation * Monte Carlo simulation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.019, year: 2008

Current activities and plans for polarized neutron instruments of the JSNS/J-PARC project

International Nuclear Information System (INIS)

Furusaka, M.

2005-01-01

Neutron polarization is one of the key technologies for the next generation megawatt-class pulsed spallation neutron sources, such as SNS in the US and the JSNS in Japan. To polarize or analyze neutron spin, several techniques are under development in Japan: a small d-spacing magnetic multilayer mirror, spin exchange type He-3 filter and a dynamical proton polarizer. Several application techniques related to polarized neutrons are also under development, such as, a microwave-induced optical nuclear polarization technique, which allows us to polarize protons in naphtalene doped with pentacene at 77 K; neutron focusing-SANS instrument utilizing a focusing magnet; a Drabkin spin-filter instrument that has two filters in series for neutron-pulse shaping

Intercomparison of radiation protection instrumentation in a pulsed neutron field

CERN Document Server

Caresana, M; Esposito, A; Ferrarini, M; Golnik, N; Hohmann, E; Leuschner, A; Luszik-Bhadra, M; Manessi, G; Mayer, S; Ott, K; Röhrich, J; Silari, M; Trompier, F; Volnhals, M; Wielunski, M

2014-01-01

In the framework of the EURADOS working group 11, an intercomparison of active neutron survey meters was performed in a pulsed neutron field (PNF). The aim of the exercise was to evaluate the performances of various neutron instruments, including commercially available rem-counters, personal dosemeters and instrument prototypes. The measurements took place at the cyclotron of the Helmholtz-Zentrum Berlin für Materialien und Energie GmbH. The cyclotron is routinely used for proton therapy of ocular tumours, but an experimental area is also available. For the therapy the machine accelerates protons to 68 MeV. The interaction of the proton beam with a thick tungsten target produces a neutron field with energy up to about 60 MeV. One interesting feature of the cyclotron is that the beam can be delivered in bursts, with the possibility to modify in a simple and flexible way the burst length and the ion current. Through this possibility one can obtain radiation bursts of variable duration and intensity. All instru...

Accounting for the thermal neutron flux depression in voluminous samples for instrumental neutron activation analysis

International Nuclear Information System (INIS)

Overwater, R.M.W.; Hoogenboom, J.E.

1994-01-01

At the Delft University of Technology Interfaculty Reactor Institute, a facility has been installed to irradiate cylindrical samples with diameters up to 15 cm and weights up to 50 kg for instrumental neutron activation analysis (INAA) purposes. To be able to do quantitative INAA on voluminous samples, it is necessary to correct for gamma-ray absorption, gamma-ray scattering, neutron absorption, and neutron scattering in the sample. The neutron absorption and the neutron scattering are discussed. An analytical solution is obtained for the diffusion equation in the geometry of the irradiation facility. For samples with known composition, the neutron flux--as a function of position in the sample--can be calculated directly. Those of unknown composition require additional flux measurements on which least-squares fitting must be done to obtain both the thermal neutron diffusion coefficient D s and the diffusion length L s of the sample. Experiments are performed to test the theory

Practical considerations in instrumental neutron activation analysis

International Nuclear Information System (INIS)

Ahmad, N.

2001-01-01

Activation analysis is a technique of elemental analysis based on the measurement of characteristics radiation from radionuclides formed directly or indirectly by activation. The activation can be induced by bombarding the material with neutrons or charged particles or gamma rays. This is a well-accepted analytical technique for the determination of composition of complex materials. This technique is also sensitive at trace levels and is almost free from analytical interferences of matrix. It is used for multi-elemental determination in rocks, minerals, alloys, biological materials, geological samples, non-destructive analysis of materials and environmental samples such as water, air particulate matter, plants, soil, sediments and diets. This method is also used for production and measurements of radioisotopes in materials of known composition, for example, when radioactivation is used for nuclear reaction studies, for flux and beam intensity measurements for trace experiments and process quality control. In this article the parameters affecting the sensitivity of instrumental neutron activation analysis are briefly discussed. (author)

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.

Upgrade of detectors of neutron instruments at Neutron Physics Laboratory in Řež

Energy Technology Data Exchange (ETDEWEB)

Litvinenko, E.I., E-mail: litvin@nf.jinr.ru [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 14980 Dubna (Russian Federation); Ryukhtin, V. [Nuclear Physics Institute of the CAS v.v.i., Řež 130, 250 68 Řež (Czech Republic); Bogdzel, A.A.; Churakov, A.V. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 14980 Dubna (Russian Federation); Farkas, G. [Charles University in Prague, Department of Physics of Material, Ke Karlovu 5, CZ-12116 Prague (Czech Republic); Hervoches, Ch.; Lukas, P. [Nuclear Physics Institute of the CAS v.v.i., Řež 130, 250 68 Řež (Czech Republic); Pilch, J. [Nuclear Physics Institute of the CAS v.v.i., Řež 130, 250 68 Řež (Czech Republic); Institute of Physics, Czech Academy of Sciences, Na Slovance 1992/2, 1822 Prague (Czech Republic); Saroun, J.; Strunz, P. [Nuclear Physics Institute of the CAS v.v.i., Řež 130, 250 68 Řež (Czech Republic); Zhuravlev, V.V. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 14980 Dubna (Russian Federation)

2017-01-01

Three neutron instruments at the Neutron Physics Laboratory (NPL) in Řež near Prague — small-angle scattering (SANS) MAUD, strain scanner SPN-100 and strain diffractometer TKSN-400 — have been modernized recently with new 2D position-sensitive detectors (PSDs) from JINR, Dubna. Here we report on the progress made in relation to the possibilities of the diffractometers due to the improved performance of the detectors. The first part of the paper is dedicated to a detailed description of the hardware and software of the PSDs, as well as its integration with the in-house experimental control software. Then practical examples of neutron scattering experiments for each of the upgraded facilities are presented.

The polarized neutron small-angle scattering instrument at BENSC Berlin

International Nuclear Information System (INIS)

Keller, T.; Krist, T.; Danzig, A.; Keiderling, U.; Mezei, F.; Wiedenmann, A.

2000-01-01

A polarized neutron beam has been installed at the small-angle neutron-scattering instrument V4 at BENSC Berlin. The main component of this new option is a 1.8 m long cavity transmission polarizer. The advantages of this device compared to the conventional bender polarizers are: (i) high transmission (35% of unpolarized beam at λ=6 A); (ii) the polarization is better than 93% in the wavelength band 4 A 3 O 4 particles embedded in a glass matrix) are presented and compared to a measurement with unpolarized neutrons

Target system neutronics study for NXGENS

International Nuclear Information System (INIS)

Willis, C.; Muhrer, G.

2007-01-01

The Materials Test Station (MTS) [E. Pitcher, G. Muhrer, H. Trellue, Neutronics Assessment of the LANSCE Materials Test Station as an Irradiation Facility for the JIMO Space Reactor, LA-CP-04-0903.], a spallation target station, planned for construction at the Los Alamos Neutron Science Center (LANSCE), will provide the opportunity to test the prototype of a long-pulse spallation source neutron scattering instrument (NXGENS). In this paper, we present the target-moderator neutronics optimization study that was performed in support of NXGENS

The MCLIB library: Monte Carlo simulation of neutron scattering instruments

Energy Technology Data Exchange (ETDEWEB)

Seeger, P.A.

1995-09-01

Monte Carlo is a method to integrate over a large number of variables. Random numbers are used to select a value for each variable, and the integrand is evaluated. The process is repeated a large number of times and the resulting values are averaged. For a neutron transport problem, first select a neutron from the source distribution, and project it through the instrument using either deterministic or probabilistic algorithms to describe its interaction whenever it hits something, and then (if it hits the detector) tally it in a histogram representing where and when it was detected. This is intended to simulate the process of running an actual experiment (but it is much slower). This report describes the philosophy and structure of MCLIB, a Fortran library of Monte Carlo subroutines which has been developed for design of neutron scattering instruments. A pair of programs (LQDGEOM and MC{_}RUN) which use the library are shown as an example.

The MCLIB library: Monte Carlo simulation of neutron scattering instruments

International Nuclear Information System (INIS)

Seeger, P.A.

1995-01-01

Monte Carlo is a method to integrate over a large number of variables. Random numbers are used to select a value for each variable, and the integrand is evaluated. The process is repeated a large number of times and the resulting values are averaged. For a neutron transport problem, first select a neutron from the source distribution, and project it through the instrument using either deterministic or probabilistic algorithms to describe its interaction whenever it hits something, and then (if it hits the detector) tally it in a histogram representing where and when it was detected. This is intended to simulate the process of running an actual experiment (but it is much slower). This report describes the philosophy and structure of MCLIB, a Fortran library of Monte Carlo subroutines which has been developed for design of neutron scattering instruments. A pair of programs (LQDGEOM and MC RUN) which use the library are shown as an example

Trace element concentrations in human bone using instrumental neutron activation analysis

International Nuclear Information System (INIS)

El-Amri, F.A.; El-Kabroun, M.A.R.

1997-01-01

Instrumental neutron activation analysis has been applied to analyze 23 bone samples obtained from Libyan patient aged (3-80) years for the study of the concentration levels of trace elements Ba, Br, Ca, Fe, Sr and Zn and their concentration patterns regarding to the age and sex of the patients. (author)

Neutron cross section standards and instrumentation. Annual report

Energy Technology Data Exchange (ETDEWEB)

Wasson, O.A.

1993-07-01

The objective of this interagency program is to provide accurate neutron interaction measurements for the US Department of Energy nuclear programs which include waste disposal, fusion, safeguards, defense, fission, and personnel protection. These measurements are also useful to other energy programs which indirectly use the unique properties of the neutron for diagnostic and analytical purposes. The work includes the measurement of reference cross sections and related neutron data employing unique facilities and capabilities at NIST and other laboratories as required; leadership and participation in international intercomparisons and collaborations; the preservation of standard reference deposits and the development of improved neutron detectors and measurement methods. A related and essential element of the program is critical evaluation of neutron interaction data including international coordinations. Data testing of critical data for important applications is included. The program is jointly supported by the Department of Energy and the National Institute of Standards and Technology. This report from the National Institute of Standards and Technology contains a summary of the accomplishments of the Neutron Cross Section Standards and Instrumentation Project during the third year of this three-year interagency agreement. The proposed program and required budget for the following three years are also presented. The program continues the shifts in priority instituted in order to broaden the program base.

Neutron cross section standards and instrumentation. Annual report

International Nuclear Information System (INIS)

Wasson, O.A.

1993-01-01

The objective of this interagency program is to provide accurate neutron interaction measurements for the US Department of Energy nuclear programs which include waste disposal, fusion, safeguards, defense, fission, and personnel protection. These measurements are also useful to other energy programs which indirectly use the unique properties of the neutron for diagnostic and analytical purposes. The work includes the measurement of reference cross sections and related neutron data employing unique facilities and capabilities at NIST and other laboratories as required; leadership and participation in international intercomparisons and collaborations; the preservation of standard reference deposits and the development of improved neutron detectors and measurement methods. A related and essential element of the program is critical evaluation of neutron interaction data including international coordinations. Data testing of critical data for important applications is included. The program is jointly supported by the Department of Energy and the National Institute of Standards and Technology. This report from the National Institute of Standards and Technology contains a summary of the accomplishments of the Neutron Cross Section Standards and Instrumentation Project during the third year of this three-year interagency agreement. The proposed program and required budget for the following three years are also presented. The program continues the shifts in priority instituted in order to broaden the program base

Data acquisition and control system for the IPNS time-of-flight neutron scattering instruments

International Nuclear Information System (INIS)

Daly, R.T.; Haumann, J.R.; Kraimer, M.R.; Lenkszus, F.R.; Lidinsky, W.P.; Morgan, C.B.; Rutledge, L.L.; Rynes, P.E.; Tippie, J.W.

1979-01-01

The Argonne Intense Pulsed Neutron System (IPNS-I) presently under construction at Argonne National Laboratory will include a number of neutron scattering instruments. This study investigates the data acquisition requirements of these instruments and proposes three alternative multiprocessor systems which will satisfy these requirements. All proposals are star configurations with a super-mini as the central node or HOST. The first proposal is based on front-ends composed of two or more 16-bit microcomputers, the second proposal is based on front ends consisting of a combination of a mini and microcomputers, and the third is based on a minicomputer with an intelligent CAMAC controller

Gadolinium for neutron detection in current nuclear instrumentation research: A review

Science.gov (United States)

Dumazert, J.; Coulon, R.; Lecomte, Q.; Bertrand, G. H. V.; Hamel, M.

2018-02-01

Natural gadolinium displays a number of remarkable physical properties: it is a rare earth element, composed of seven stable or quasi-stable isotopes, with an exceptionally high magnetization and a Curie point near room temperature. Its use in the field of nuclear instrumentation historically relates to its efficiency as a neutron poison in power reactors. Gadolinium is indeed the naturally occurring element with the highest interaction probability with neutrons at thermal energy, shared between Gd-157 (15.65%, 254000 b cross section) and Gd-155 (14.8%, 60900 b) isotopes. Considering that neutron capture results in an isotopic change, followed by a radiative rearrangement of nuclear and atomic structures, Gd may be embodied not merely as a neutron poison but as a neutron converter into a prompt photon and an electron source term. Depending on the nature and energy of the reaction products (from a few-keV Auger electrons up to 8 MeV gamma rays) that the detector aims at isolating as an indirect neutron signature, a variety of sensor media and counting methods have been introduced during the last decades. This review first draws a theoretical description of the radiative cascade following Gd(n , γ) capture. The cascade may be subdivided into regions of interest, each corresponding to dedicated detection designs and optimizations whose current status is detailed. This inventory has allowed the authors to extract and benchmark key figures of merit for the definition of a detection scheme: neutron attenuation, neutron sensitivity (cps/nv), gamma rejection, neutron detection limit in a mixed field, intrinsic or extrinsic moderation, and transportability. On this basis, the authors have identified promising paths for Gd-based neutron detection in contemporary instrumentation.

Elemental analysis using instrumental neutron activation analysis and inductively coupled plasma atomic emission spectrometry: a comparative study

International Nuclear Information System (INIS)

Chung, Yong Sam; Choi, Kwang Soon; Moon, Jong Hwa; Kim, Sun Ha; Lim, Jong Myoung; Kim, Young Jin; Quraishi, Shamshad Begum

2003-05-01

Elemental analyses for certified reference materials were carried out using instrumental neutron activation analysis and inductively coupled plasma-atomic emission spectrometry. Five Certified Reference Materials (CRM) were selected for the study on comparative analysis of environmental samples. The CRM are Soil (NIST SRM 2709), Coal fly ash (NIST SRM 1633a), urban dust (NIST SRM 1649a) and air particulate on filter media (NIST SRM 2783 and human hair (GBW 09101)

Study of influence of transport performance of the neutron guide

International Nuclear Information System (INIS)

Li Xinxi; Wang Yan; Huang Chaoqiang; Chen Bo; Chen Liang

2009-01-01

For the sake of improving the performance of the neutron scattering instrument, usually we need use the neutron guide, it's very important to select the right type and optimizing of neutron guide. The papers calculate the focus neutron guide and the single channel neutron guide by numeric method. The results shows that the choice of neutron guide should consult the resolution requirement of neutron scattering instrument, and the length of the neutron guide should be optimized. The calculation results can be the theoretical reference for the design of neutron scattering instrument. (authors)

IB: A Monte Carlo simulation tool for neutron scattering instrument design under PVM and MPI

International Nuclear Information System (INIS)

Zhao Jinkui

2011-01-01

Design of modern neutron scattering instruments relies heavily on Monte Carlo simulation tools for optimization. IB is one such tool written in C++ and implemented under Parallel Virtual Machine and the Message Passing Interface. The program was initially written for the design and optimization of the EQ-SANS instrument at the Spallation Neutron Source. One of its features is the ability to group simple instrument components into more complex ones at the user input level, e.g. grouping neutron mirrors into neutron guides and curved benders. The simulation engine manages the grouped components such that neutrons entering a group are properly operated upon by all components, multiple times if needed, before exiting the group. Thus, only a few basic optical modules are needed at the programming level. For simulations that require higher computer speeds, the program can be compiled and run in parallel modes using either the PVM or the MPI architectures.

Study of trace metals in phosphorite by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Delgado, J.U.

1984-01-01

Methods to determine U, Th and other constituent elements in mineral matrices by the instrumental neutron activation analysis (INAA) have been widely developed. The precise knowledge of these constituent elements is very important for the nuclear technology development. This justifies the use of a technique capable to extract information from small samples. The present work aimed the study of the phosphorites deriving from the State of Pernambuco (PE, Brazil). Its uranium concentration corresponds to one of the highest values found in industrial exploration of phosphate rocks. An experimental methodology based on the INAA associated to the cluster technique was developed. Concentrations of 22 different elements present in the ore were determined with less than 10% uncertainty. The results have shown high correlations in behavior between uranium and rare earth metals. However, the inverse was noted in relation to transition metals. These results indicate the applicability of this method to determine concentrations as well as to classify correlated element groups in mineral matrices. (Author) [pt

Study of impurity composition of some compounds of refractory metals by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Kaganov, L.K.; Dzhumakulov, D.T.; Mukhamedshina, N.M.

1994-01-01

The compounds of refractory transition metals find wide application in all fields of engineering, in particular in microelectronics to manufacture contact-barrier layers of thin-film current-conducting systems of silicon instruments, large and very large scale integrated circuits. Production of such materials is realted with the need to apply the analytical control methods that allow to determine a large number of elements with high reliability. The instrumental neutron-activation techniques have been developed to determine impurity composition of the following compounds: MoSi 2 , WSi 2 , TiB 2 , NbB 2 , TiC, NbC

The development of neutron detectors for the GEM instrument at ISIS

International Nuclear Information System (INIS)

Rhodes, N.J.; Johnson, M.W.; Schooneveld, E.M.

2001-01-01

GEM is a new General Materials diffractometer now being commissioned at ISIS. To meet its broad based scientific programme GEM requires a large area position sensitive detector which covers a wide range of scattering angles and exhibits a high neutron count rate stability. This paper discusses the design of a ZnS/ 6 Li fibre coupled detector array that meets the GEM requirements. Typical detector characteristics are documented together with the current status of the project. Two thirds of the detector array are operational and from the results obtained to date it is already obvious that the impact of this instrument on neutron scattering studies will be profound. (author)

Proceedings of the workshop on neutron scattering instrumentation for SNQ

International Nuclear Information System (INIS)

Scherm, R.; Stiller, H.

1984-10-01

These proceedings contain the articles presented at the named workshop. These concern instrumentation for neutron diffraction with special regards to small angle scattering, diffuse scattering, inelastic scattering, high resolution spectroscopy, and special techniques. (HSI)

Instrumentation of a manually programmed neutron diffractometer

DEFF Research Database (Denmark)

Hansen, K.B.; Neisig, K.E.

1966-01-01

This paper describes essentially the digital part of the instrumentation for a neutron diffractometer in which the measuring procedure is governed by a control unit involving a fixed number of program points. A simultaneously running test program monitors the information transfer from the data...... sources and to the print-out in table form. The experimental conditions must be set by a panel switch selected program, which allows a desired parameter program to be executed....

Absolute instrumental neutron activation analysis at Lawrence Livermore Laboratory

International Nuclear Information System (INIS)

Heft, R.E.

1977-01-01

The Environmental Science Division at Lawrence Livermore Laboratory has in use a system of absolute Instrumental Neutron Activation Analysis (INAA). Basically, absolute INAA is dependent upon the absolute measurement of the disintegration rates of the nuclides produced by neutron capture. From such disintegration rate data, the amount of the target element present in the irradiated sample is calculated by dividing the observed disintegration rate for each nuclide by the expected value for the disintegration rate per microgram of the target element that produced the nuclide. In absolute INAA, the expected value for disintegration rate per microgram is calculated from nuclear parameters and from measured values of both thermal and epithermal neutron fluxes which were present during irradiation. Absolute INAA does not depend on the concurrent irradiation of elemental standards but does depend on the values for thermal and epithermal neutron capture cross-sections for the target nuclides. A description of the analytical method is presented

Analysis of atmospheric particulate samples via instrumental neutron activation analysis

International Nuclear Information System (INIS)

Greenberg, R.R.

1990-01-01

Instrumental neutron activation analysis (INAA) is a powerful analytical technique for the elemental characterization of atmospheric particulate samples. It is a true multielement technique with adequate sensitivity to determine 30 to 40 elements in a sample of atmospheric particulate material. Its nondestructive nature allows sample reanalysis by the same or a different analytical technique. In this paper as an example of the applicability of INAA to the study of atmospheric particulate material, a study of the emissions from municipal incinerators is described

Analysis and simulation of a small-angle neutron scattering instrument on a 1 MW long pulse spallation source

International Nuclear Information System (INIS)

Olah, G.A.; Hjelm, R.P.; Lujan, M. Jr.

1996-01-01

We studied the design and performance of a small-angle neutron scattering (SANS) instrument for a proposed 1 MW, 60 Hz long pulsed spallation source at the Los Alamos Neutron Science Center (LANSCE). An analysis of the effects of source characteristics and chopper performance combined with instrument simulations using the LANSCE Monte Carlo instrument simulations package shows that the T 0 chopper should be no more than 5 m from the source with the frame overlap and frame definition choppers at 5.6 and greater than 7 m, respectively. The study showed that an optimal pulse structure has an exponential decaying tail with τ ∼ 750 μs. The Monte Carlo simulations were used to optimize the LPSS SANS, showing that an optimal length is 18 m. The simulations show that an instrument with variable length is best to match the needs of a given measurement. The performance of the optimized LPSS instrument was found to be comparable with present world standard instruments

Pollution of agricultural crops with lanthanides, thorium and uranium studied by instrumental and radiochemical neutron activation analysis

International Nuclear Information System (INIS)

Kucera, J.; Mizera, J.; Randa, Z.; Vavrova, M.

2007-01-01

The lanthanide elements, Th and U were measured in soils and agricultural crops collected in an area polluted by emissions from a phosphate fertilizer plant. Concentrations of the above elements in the soil and crop samples were determined by instrumental neutron activation analysis (INAA). Selected crop samples were also analyzed using radiochemical neutron activation analysis (RNAA) based on alkaline-oxidative fusion of the irradiated samples followed by precipitation of REE oxalates. Elevated levels of lanthanides, Th and U were found in some samples, especially in wheat chaff and parsley. (author)

A Unique Outside Neutron and Gamma Ray Instrumentation Development Test Facility at NASA's Goddard Space Flight Center

Science.gov (United States)

Bodnarik, J.; Evans, L.; Floyd, S.; Lim, L.; McClanahan, T.; Namkung, M.; Parsons, A.; Schweitzer, J.; Starr, R.; Trombka, J.

2010-01-01

An outside neutron and gamma ray instrumentation test facility has been constructed at NASA's Goddard Space Flight Center (GSFC) to evaluate conceptual designs of gamma ray and neutron systems that we intend to propose for future planetary lander and rover missions. We will describe this test facility and its current capabilities for operation of planetary in situ instrumentation, utilizing a l4 MeV pulsed neutron generator as the gamma ray excitation source with gamma ray and neutron detectors, in an open field with the ability to remotely monitor and operate experiments from a safe distance at an on-site building. The advantage of a permanent test facility with the ability to operate a neutron generator outside and the flexibility to modify testing configurations is essential for efficient testing of this type of technology. Until now, there have been no outdoor test facilities for realistically testing neutron and gamma ray instruments planned for solar system exploration

Neutron and synchrotorn x-ray small angle scattering instruments for applications in biology at the Brookhaven National Laboratory

International Nuclear Information System (INIS)

Schoenborn, B.P.; Wise, D.S.; Schneider, D.K.

1983-01-01

Facilities for small angle x-ray and neutron scattering are described, with emphasis on the characterization of the primary beam of the neutron instrument and the spectrometer control logic of the synchrotron instrument

Determination of toxic elements in tobacco by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Yaprak, G.; Cam, N.F.

1998-01-01

The concentration of toxic elements in the tobacco of six different brands of domestic and two brands of imported cigarettes heavily smoked in Turkey were determined using instrumental neutron activation analysis (INAA)

Neutron-gamma flux and dose calculations for feasibility study of DISCOMS instrumentation in case of severe accident in a GEN 3 reactor

Science.gov (United States)

Brovchenko, Mariya; Duhamel, Isabelle; Dechenaux, Benjamin

2017-09-01

The present paper presents the study carried out in the frame of the DISCOMS project, which stands for "DIstributed Sensing for COrium Monitoring and Safety". This study concerns the calculation of the neutron and gamma radiations received by the considered instrumentation during the normal reactor operation as well as in case of a severe accident for the EPR reactor, outside the reactor pressure vessel and in the containment basemat. This paper summarizes the methods and hypotheses used for the particle transport simulation outside the vessel during normal reactor operation. The results of the simulations are then presented including the responses for distributed Optical Fiber Sensors (OFS), such as the gamma dose and the fast neutron fluence, and for Self Powered Neutron Detectors (SPNDs), namely the neutron and gamma spectra. Same responses are also evaluated for severe accident situations in order to design the SPNDs being sensitive to the both types of received neutron-gamma radiation. By contrast, fibers, involved as transducers in distributed OFS have to resist to the total radiation gamma dose and neutron fluence received during normal operation and the severe accident.

Study of the long-range transport of atmospheric pollutants by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Jin Yangshao

1994-01-01

Aerosol samples were collected to study the characteristics of marine aerosols in the different western Pacific ocean areas. During the first cruise from 15 October to 25 November 1989, aerosol samples were collected with a kA-200 Andersen cascade impactor and a kB-120 sampler. Instrumental neutron activation analysis was used to determine the elemental composition of the aerosols. The concentrations of crustal and pollution elements in aerosols were higher over the ocean area close to the China coast and decreased very rapidly with increasing distance from land. The morphology and elemental composition of aerosol particles showed that the seasalt particles may conglomerate with small crustal and pollution particles from land to form large particles. (author). 4 refs, 1 fig., 1 tab

A pilot study to measure levels of selected elements in Thai foods by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Laoharojanaphand, S.; Busamongkol, A.; Permnamtip, V.; Judprasong, K.; Chatt, A.

2012-01-01

A pilot study was carried out to evaluate the scope of instrumental neutron activation analysis (INAA) for measuring the levels of selected elements in a few commonly consumed food items in Thailand. Several varieties of rice, beans, aquatic food items, vegetables and soybean products were bought from major distribution centers in Bangkok, Thailand. Samples were prepared according to the protocols prescribed by the nutritionist for food compositional analysis. Levels of As, Br, Ca, Cd, Cl, Cr, Cu, Fe, K, Mg, Mn, and Zn were measured by INAA using the irradiation and counting facilities available at the Thai Research Reactor with the maximum in-core thermal neutron flux of 3 x 10 13 cm -2 s -1 of the Thailand Institute of Nuclear Technology in Bangkok. Selenium was determined by cyclic INAA using the Dalhousie University SLOWPOKE-2 Reactor facilities in Halifax, Canada at a thermal neutron flux of 2.5 x 10 11 cm -2 s -1 . Both cooked and uncooked foods were analyzed. The elemental composition of food products was found to depend significantly on the raw material as well as the preparation technique. (author)

Microprocessor-controlled data-acquisition instrument for neutron-activation measurements

International Nuclear Information System (INIS)

Jones, B.A.

1981-01-01

This paper describes a microprocessor controlled data acquisition instrument designed at Lawrence Livermore National Laboratory to provide experimenters with a diagnostic tool for measuring the performance of laser imploded fusion targets via neutron activation techniques. This instrument features the ability to count four independent inputs simultaneously while providing a front panel readout of these inputs, plus a time of day clock. A hardcopy printout of the data is also provided by a built-in thermal printer. All running modes and parameters are user selectable via a front panel keypad, and a complete set of internal self-testing diagnostics are available for debug

The upgraded cold neutron triple-axis spectrometer FLEXX – enhanced capabilities by new instrumental options

Directory of Open Access Journals (Sweden)

Habicht Klaus

2015-01-01

Full Text Available The upgrade of the cold neutron triple axis spectrometer FLEXX, a work-horse instrument for inelastic neutron scattering matching the sample environment capabilities at Helmholtz-Zentrum Berlin, has been successfully accomplished. Experiments confirmed an order of magnitude gain in flux now allowing for intensity demanding options to be fully exploited at FLEXX. In this article, we describe the layout and design of two newly available FLEXX instrument options in detail. The new Heusler analyzer gives an increase of the detected polarized neutron flux due to its superior focusing properties, significantly improving the feasibility of future polarized and neutron resonance spin echo experiments. The MultiFLEXX option provides simultaneous access to large regions in wavevector and energy space for inelastic excitations thus adding mapping capabilities to the spectrometer.

Instrumental neutron activation analysis in study of the toxicity of trialkyltin-methacrylic copolymer as an antifouling agent

International Nuclear Information System (INIS)

Lin, S.M.; Ching, C.H.; Tseng, C.L.; Yang, M.H.

1985-01-01

The analysis of tin in biological materials is rarely reported. In this study instrumental neutron activation analysis was used to determine the tin together with some other trace elements in various organs of rats treated with trialkyltin-methacrylic copolymer. No appreciable accumulation of tin and variation of distribution of trace elements (Cr, Fe, Zn and Co) in various organs were found. The pathological changes in the liver sections can not be observed either. This, therefore, indicates that the toxicity of trialkyltin-methacrylic copolymer is low, if any. (author)

Instrumentation for PSD based neutron diffractometers at Dhruva reactor

International Nuclear Information System (INIS)

Pande, S.S.; Borkar, S.P.; Prafulla, S.; Srivastava, V.D.; Behare, A.; Mukhopadhyay, P.K.; Ghodgaonkar, M.D.; Kataria, S.K.

2004-01-01

Linear position sensitive detectors (PSDs) are widely used to configure neutron diffractometers and other instruments. Necessary front-end electronics and a data acquisition system is developed to cater to such instruments built around the Dhruva research reactor in BARC. These include three diffractometers with multiple PSDs and four with single PSD. The front-end electronics consists of high voltage units, preamplifiers, shaping amplifiers, ratio ADCs (RDC). The data acquisition system consists of an interface card and software. Commercially available hardware like temperature controller or stepper motor controller connected over GPIB or RS232 are also integrated in the data acquisition system. The data acquisition is automated so that it can continue unattended for control parameter like temperature, thus enabling optimum utilization of available beam time. The instrumentation is scalable and can be easily configured for various instrumental requirements. The front-end electronics and the data acquisition system are described here. (author)

Instrumental Neutron Activation Analysis- INAA: environmental studies in Das Velhas Basin, Minas Gerais, Brazil

International Nuclear Information System (INIS)

Rabelo V, M.A.; Andrade Q, M.T.; Araujo M, R.; Albernaz A, I.; Oliveira, A.H. de

2006-01-01

The Instrumental Neutron Activation Analysis - INAA was applied to determine concentrations of several elements in unpolluted areas and in the mining and farming region of the Das Velhas Basin, Minas Gerais State, Brazil. INAA was applied using the TRIGA Mark I IPR - R1 reactor at the Nuclear Technology Development Center of the National Committee of Nuclear Energy (CDTN/CNEN), in Belo Horizonte city, Minas Gerais State. At 100 kW of potency the flux of neutrons is 6.6 10 11 n.cm -2 .s -1 . The samples analyzed were: water; sediment; gravel of gold mine and forage. The obtained results for the Das Velhas Basin in water and sediment samples - mining companies region - show a high level (μg/g) of contamination with the analyzed elements, mainly in the sediment samples. During the period of floods, in farming region hundreds of kilometers away, contamination is found in fish and forage, reaching and harming both people and animals that live in the marginal region. (Author)

Large area window on vacuum chamber surface for neutron scattering instruments

International Nuclear Information System (INIS)

Itoh, Shinichi; Yokoo, Tetsuya; Ueno, Kenji; Suzuki, Junichi; Teraoku, Takuji; Tsuchiya, Masao

2012-01-01

The feasibility of a large area window using a thin aluminum plate on the surface of the vacuum chamber for neutron scattering instruments at a pulsed neutron source was investigated. In the prototype investigation for a window with an area of 1m×1.4m and a thickness of 1 mm, the measured pressure dependence of the displacement agreed well with a calculation using a nonlinear strain–stress curve up to the plastic deformation region. In addition, we confirmed the repetition test up to 2000 pressurization-and-release cycles, which is sufficient for the lifetime of the vacuum chamber for neutron scattering instruments. Based on these investigations, an actual model of the window to be mounted on the vacuum chamber of the High Resolution Chopper Spectrometer (HRC) at J-PARC was designed. By using a calculated stress distribution on the window, the clamping structure capable of balancing the tension in the window was determined. In a model with a structure identical to the actual window, we confirmed the repetition test over more than 7000 pressurization-and-release cycles, which shows a lifetime long enough for the actual usage of the vacuum chamber on the HRC.

A survey of environmental exposure amongst locoshed workers by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Singh, V.K.N.; Garg, A.N.

1995-01-01

Instrumental neutron activation analysis (INAA) has been used for the determination of 16 elements in hair of locoshed workers (n=10) to study environmental exposure. A comparison of mean elemental contents with control (n=11) shows a significant enhancement for Cr, Th, Ca, Se and Na whereas Br and Sb show a declining trend. (author). 4 refs., 1 tab

Trace elements in Turkish tobacco determined by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Gulovali, M.C.

1977-01-01

This study was undertaken to determine the concentration of trace elements in nine different brands of Turkish cigarette tobacco, pipe tobacco and tobacco ash. Instrumental neutron activation analysis was employed, and a gamma-ray spectrometer consisting of 40 cm 3 Ge(Li) detector coupled to 1024 and 4096-channel analyzers were used. Samples were irradiated at a thermal neutron flux of about 10 13 cm -2 sec -1 . Concentrations of Na, K, Sc, Cr, Fe, Co, Zn, As, Se, Br, Rb, Sb, Cs, Ba, La, Ce, Eu, Hf, Hg and Th were determined in tobacco and ash; percent transference of these elements into ash were calculated. It was found out that trace elements in cigarette tobacco are left in the ash but only a small percentage is transferred into the smoke

Instrumentation for PSD-based neutron diffractometers at Dhruva reactor

Science.gov (United States)

Pande, S. S.; Borkar, S. P.; Prafulla, S.; Srivastava, V. D.; Behare, A.; Mukhopadhyay, P. K.; Ghodgaonkar, M. D.; Kataria, S. K.

2004-08-01

Linear position sensitive detectors (PSDs) are widely used to configure neutron diffractometers and other instruments. Necessary front-end electronics and a data acquisition system [1] is developed to cater to such instruments built around the Dhruva research reactor in BARC. These include three diffractometers with multiple PSDs and four with single PSD. The front-end electronics consists of high voltage units, preamplifiers [2], shaping amplifiers, ratio ADCs (RDC) [3]. The data acquisition system consists of an interface card and software. Commercially available hardware like temperature controller or stepper motor controller connected over GPIB or RS232 are also integrated in the data acquisition system. The data acquisition is automated so that it can continue unattended for control parameter like temperature, thus enabling optimum utilization of available beam time. The instrumentation is scalable and can be easily configured for various instrumental requirements. The front-end electronics and the data acquisition system are described here.

Instrumentation system for pulsed neutron generator. Pt. 1. Electronic control and data acquisition

International Nuclear Information System (INIS)

Burda, J.; Igielski, A.; Janik, W.; Kosik, M.; Kurowski, A.; Zaleski, T.

1997-01-01

The paper presents an electronic instrumentation system which is successfully applied for pulsed neutron generator and measurements. In the paper there are described in details all modernized parts of the system as well as new designed and applied ones. The set of diagrams is enclosed. An important part of the system has been designed and built in the Neutron Transport Physics Laboratory. (author)

Instrumental neutron activation analysis of tree rings for dendrochemical studies

International Nuclear Information System (INIS)

Schaumloffel, J.C.; Filby, R.H.

1996-01-01

Instrumental neutron activation analysis (INAA) was employed to determine zinc, cadmium and potassium concentrations in the growth rings of ponderosa pine (Pinus ponderosa Dougl.) trees growing along the shores of Lake Roosevelt in Washington State, U.S.A. where mineral processing activities have resulted in high burdens of zinc and cadmium in the lake sediments. The tree growing along the contaminated waterway display elevated concentrations of zinc in its growth rings relative to a tree growing along an uncontaminated tributary of Lake Roosevelt. Cadmium concentrations in the growth rings from both sites are similar from 1988 to 1993. Water quality data indicate an increased concentration of cadmium in the lake from 1984 to 1988. The increased concentrations of cadmium in the lake water were reflected in apparent increases in concentrations of cadmium in individual rings of the tree sampled at the contaminated site. This suggests that translocation of cadmium in the sapwood of heartwood-forming species does not occur in the short term, and thus may not be a limiting factor in using trees as environmental monitors for cadmium. In addition, five-year tree ring segments were analyzed and subsequently reanalyzed as individual single-year ring segments. The analytical data obtained for the pooled individual rings are essentially the same as for the five-year segments, demonstrating the utility of NAA for dendrochemical studies. (author). 24 refs., 5 figs., 2 tabs

Nuclear data and the effects of its inconsistency on instrumental neutron activation analysis

International Nuclear Information System (INIS)

Ahmed, Y.A.; Ewa, I.O.B.; Umar, I.M.

2006-04-01

In this study, we examine the role of nuclear data in Instrumental Neutron Activation Analysis (INAA) particularly as it affects determination of reactor flux parameters and application of comparator methods. The work reviewed the available sources of nuclear data, the variations that exist from one source to the other and the effects of such variations on INAA. Measurement of Neutron flux parameters in inner and outer irradiation channel of a miniature neutron source reactor was carried out using two independent nuclear data sources to investigate the effects of inconsistency of nuclear data on the precision of analytical result. The result obtained shows a slight variation of flux parameters with nuclear data source. It was also observed that modification of the earlier compiled basic nuclear data lead to inconsistencies in the secondary data that applies it. (author)

Study of the trace element content in human cataractous lenses by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Kouris, T.; Theodossiadis, G.; Papadopoulou, C.; Kanias, G.D.; Baikraktari-Kouri, E.

1986-01-01

Cataract is a very common disease of the eye lens known since the ancient times. Different mechanisms are responsible for the biogenesis of cataract but the greater number of scientists agree with the theory that cataract formation can be attributed to metabolism disorders in the lens. Instrumental neutron activation analysis has been applied in this work for the determination of the following trace elements: antimony, cobalt, iron, rubidium, selenium and zinc in human lenses with mature cataract. The obtained results are statistically treated and correlated with age and sex of patients. Based on these findings the concentration of each studied element does not have any correlation with the age and/or sex of the patients i.e. when the lens becomes totally opaque. (author)

Study of atmospheric aerosols in Zaire by instrumental neutron activation analysis, atomic absorption spectrophotometry and ion-exchange chromatography

International Nuclear Information System (INIS)

Tshiashala, M.D.; Lumu, B.M.; Matamba, K.; Ronneau, C.

1992-01-01

Instrumental neutron activation analysis and atomic absorption spectroscopy were applied to the determination of trace element abundances in airborne particulate matter collected throughout Kinshasa, Zaire. Statistical treatment of the resulting data was used to assess the variations between sites and to identify the sources of the pollutants. 10 refs, 5 tabs

Study of some Ayurvedic Indian medicinal plants for the essential trace elemental contents by instrumental neutron activation analysis and atomic absorption spectroscopy techniques

International Nuclear Information System (INIS)

Lokhande, R.S.; Singare, P.U.; Andhele, M.L.; Acharya, R.; Nair, A.G.C.; Reddy, A.V.R.

2009-01-01

Elemental analysis of some medicinal plants used in the Indian Ayurvedic system was performed by employing instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted by gamma ray spectrometry using an efficiency calibrated high resolution high purity germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the elements under study. The variation in elemental concentration in same medicinal plants samples collected in summer, winter and rainy seasons was studied and the biological effects of these elements on human beings are discussed. (orig.)

New instruments and science around SINQ. Lecture notes of the 4. summer school on neutron scattering

International Nuclear Information System (INIS)

Furrer, A.

1996-01-01

The spallation neutron source at PSI will be commissioned towards the end of this year together with a set of first generation instruments. This facility should then be available for the initial scientific work after spring next year. One of the main goals of this year's summer school for neutron scattering was therefore the preparation of the potential customers at this facility for its scientific exploitation. In order to give them the - so to speak - last finish, we have dedicated the school to the discussion of the instruments at SINQ and their scientific potential. These proceedings are divided into two parts: Part A gives a complete description of the first-generation instruments and sample environment at SINQ. For all the instruments the relevant parameters for planning experiments are listed. Part A is completed by G. Bauer's summary on experimental facilities and future developments at SINQ. Part B presents the lecture notes dealing with relevant applications of neutron based techniques in science and technology. The summary lecture by S.W. Lovesey is also included. (author) figs., tabs., refs

New instruments and science around SINQ. Lecture notes of the 4. summer school on neutron scattering

Energy Technology Data Exchange (ETDEWEB)

Furrer, A [ed.

1996-11-01

The spallation neutron source at PSI will be commissioned towards the end of this year together with a set of first generation instruments. This facility should then be available for the initial scientific work after spring next year. One of the main goals of this year`s summer school for neutron scattering was therefore the preparation of the potential customers at this facility for its scientific exploitation. In order to give them the - so to speak - last finish, we have dedicated the school to the discussion of the instruments at SINQ and their scientific potential. These proceedings are divided into two parts: Part A gives a complete description of the first-generation instruments and sample environment at SINQ. For all the instruments the relevant parameters for planning experiments are listed. Part A is completed by G. Bauer`s summary on experimental facilities and future developments at SINQ. Part B presents the lecture notes dealing with relevant applications of neutron based techniques in science and technology. The summary lecture by S.W. Lovesey is also included. (author) figs., tabs., refs.

Trace elements in Turkish tobacco determined by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Guelovali, M.C.; Guenduez, G.

1983-01-01

The concentration of 20 trace elements in nine brands of Turkish cigarette tobacco and in a brand of pipe tobacco ash has been determined by instrumental neutron activation analysis. The percent transference of elements into smoke has been estimated from the amounts remaining in the ash. (author)

Instrumental neutron activation analysis of wheat bunt spores

Energy Technology Data Exchange (ETDEWEB)

Liu, Y G; Schmitt, R A [Oregon State Univ., Corvallis (USA). Dept. of Chemistry; Oregon State Univ., Corvallis (USA). Radiation Center); Trione, E J [Oregon State Univ., Corvallis (USA). Dept. of Botany; Laul, J C [Battelle Pacific Northwest Labs., Richland, WA (USA)

1982-01-01

The concentrations of seventeen elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Zn, Br, Rb, La, Sm) in two species of fungus which cause wheat bunt disease, Tilletia caries (DC.) Tul. and Tilletia controversa Kuehn, were determined by instrumental neutron activation analysis. A standard sequential INAA procedure was used. Differences in the K and Cl concentrations between these two species of spores are large and therefore can be used as a criterion of distinguishing between the two species of fungus.

Multielement analysis of Nigerian chewing sticks by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Asubiojo, O.I.; Guinn, V.P.

1982-01-01

In Nigeria, various parts of various species of native plants have long been used for dental hygiene, with reportedly considerable effectiveness. These materials are known as 'chewing sticks'. This study was an effort to ascertain whether any unusual trace element concentrations might be present in Nigerian chewing sticks. Results are presented for 17 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Mn, Fe, Co, Zn, Br, Cs, La, Sm, Au) detected and measured in 12 species of such plants, via instrumental thermal-neutron activation analysis. (author)

Air pollution assessment in two Moroccan cities using instrumental neutron activation analysis on bio-accumulators

International Nuclear Information System (INIS)

Embarch, K.; Moutea, Z.; Bounakhla, M.; Cherkaoui, R.; Chouak, A.; Lferde, M.; Gaudry, A.

2008-01-01

Full text: Biomonitoring is an appropriate tool for the air pollution assessment studies. In this work, lichens and barks have been used as bio-accumulators in several sites in two Moroccan cities (Rabat and Mohammadia). The specific ability of absorbing and accumulating heavy metals and toxic element from the air, their longevity and resistance to the environmental stresses, make those bioindicators suitable for this kind of studies. The Instrumental Neutron Activation Analysis (INAA) is universally accepted as one of the most reliable analytical tools for trace and ultra-trace elements determination. Its use in trace elements atmospheric pollution related studies has been and is still extensive as can be demonstrated by several specific works and detailed reviews. In this work, a preliminary investigation employing lichens, barks and instrumental neutron activation analysis (INAA) was carried out to evaluate the trace elements distribution in six different areas of Rabat and Mohammadia cities characterised by the presence of many industries and heavy traffic. Samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted using high-resolution Germanium-Lithium detectors. More than 30 elements were determined using two modes : short irradiation (1 minute) and long irradiation (17 hours). Accuracy and quality control were assessed using the reference standard material IAEA-336. This was less than 1% for major and about 5 to 10% for traces. [fr

Study on elements concentrations on seabird feathers by instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Theophilo, Carolina Y.S.; Moreira, Edson G. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), São Paulo, SP (Brazil); Figueira, Rubens C.L.; Colabuono, Fernanda I., E-mail: carolina.theophilo@gmail.com, E-mail: emoreira@ipen.br, E-mail: rfigueira@usp.br, E-mail: ficolabuono@gmail.com [Universidade de São Paulo (USP), São Paulo, SP (Brazil). Instituto Oceanográfico

2017-07-01

Seabirds are very sensitive to environmental changes and because of their large longevity they are also sensitive to cumulative impacts. These birds usually occupy the higher trophic levels. White-chinned petrel (Procellaria aequinoctialis) and black-browed albatross (Thalassarche melanophris) are Procellariiformes, which is a seabird order, composed of 4 families. In the last years, researches are being done and actions are being taken to reduce the mortality of albatrosses and petrels caused by human activities. Due to the great ecological importance of these birds and the developed work with Procellariiformes, this study purpose is to quantify the Br, Cl, Cu, K, Mg, Mn, Na and V elements in white-chinned petrel and black-browed albatross feathers. Bird specimens were killed accidentally by pelagic longline fisheries operating off southern Brazil. Feathers were cleaned with acetone and then milled in a cryogenic mill. Instrumental Neutron Activation Analysis (INAA) was used for quantification of the element concentrations and measurements of induced activities were performed in a HPGe detector for gamma ray spectrometry. The obtained results on feathers showed that concentrations in these birds are not higher than others studies with the same species and, with exception of Br, there are no significant differences between elements mean concentrations in the two seabirds. (author)

Study on elements concentrations on seabird feathers by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Theophilo, Carolina Y.S.; Moreira, Edson G.; Figueira, Rubens C.L.; Colabuono, Fernanda I.

2017-01-01

Seabirds are very sensitive to environmental changes and because of their large longevity they are also sensitive to cumulative impacts. These birds usually occupy the higher trophic levels. White-chinned petrel (Procellaria aequinoctialis) and black-browed albatross (Thalassarche melanophris) are Procellariiformes, which is a seabird order, composed of 4 families. In the last years, researches are being done and actions are being taken to reduce the mortality of albatrosses and petrels caused by human activities. Due to the great ecological importance of these birds and the developed work with Procellariiformes, this study purpose is to quantify the Br, Cl, Cu, K, Mg, Mn, Na and V elements in white-chinned petrel and black-browed albatross feathers. Bird specimens were killed accidentally by pelagic longline fisheries operating off southern Brazil. Feathers were cleaned with acetone and then milled in a cryogenic mill. Instrumental Neutron Activation Analysis (INAA) was used for quantification of the element concentrations and measurements of induced activities were performed in a HPGe detector for gamma ray spectrometry. The obtained results on feathers showed that concentrations in these birds are not higher than others studies with the same species and, with exception of Br, there are no significant differences between elements mean concentrations in the two seabirds. (author)

Instrumental neutron activation analysis of phosphorus in biological materials by Bremsstrahlung measurement

International Nuclear Information System (INIS)

Bajo, S.; Wyttenbach, A.

1986-12-01

The determination of phosphorus in biological materials by instrumental neutron activation via the reaction 31 P (n,γ) 32 P is described. The Bremsstrahlung produced by 32 P is measured in a well-type NaI(Tl) detector. The samples are measured within the polyethylene irradiation container with no changes between irradiation and measurement. The sources of error were studied and the proposed method was applied to the determination of phosphorus in ten internationally certified materials. (author)

Multielement analysis of Nigerian chewing sticks by instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Asubiojo, O.I.; Guinn, V.P. (California Univ., Irvine (USA). Dept. of Chemistry); Okunuga, A. (California Polytechnic Univ., Pomona, CA (USA))

1982-01-01

In Nigeria, various parts of various species of native plants have long been used for dental hygiene, with reportedly considerable effectiveness. These materials are known as 'chewing sticks'. This study was an effort to ascertain whether any unusual trace element concentrations might be present in Nigerian chewing sticks. Results are presented for 17 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Mn, Fe, Co, Zn, Br, Cs, La, Sm, Au) detected and measured in 12 species of such plants, via instrumental thermal-neutron activation analysis.

Study of Material Moisture Measurement Method and Instrument by the Combination of Fast Neutron Absorption and γ Absorption

International Nuclear Information System (INIS)

Hou Chaoqin; Gong Yalin; Zhang Wei; Shang Qingmin; Li Yanfeng; Gou Qiangyuan; Yin Deyou

2010-01-01

To solve the problem of on-line sinter moisture measurement in the iron making plant, we developed material moisture measurement method and instrument by the combination of fast neutron absorption and y-absorption. It overcomes the present existed problems of other moisture meters for the sinter. Compare with microwave moisture meter, the measurement dose not affected by conductance and magnetism of material; to infrared moisture meter, the measurement result dose not influenced by colour and light-reflect performance of material surface, dose not influenced by changes of material kind; to slow neutron scatter moisture meter, the measurement dose not affected by density of material and thickness of hopper wall; to the moisture measurement meter which combined by slow neutron penetrate through and y-absorption, there are definite math model and good linear relation between the measurement values, and the measurement dose not affected by material thickness, changes of material form and component. (authors)

The instrumental neutron-activation analysis of granites from the Bushveld Complex

International Nuclear Information System (INIS)

Watterson, J.I.W.

1978-01-01

Three methods of instrumental neutron-activation analysis, 14MeV, reactor thermal, and reactor epithermal, are compared for the analysis of granites form the Bushveld Complex. A total of 34 elements can be determined in the granites by these methods. Samples from the Zaaiplaats area were analysed by thermal neutron activation, and 22 elements were determined in all of them. These elements were used to distinguish between the mineralized Bobbejaankop and Lease granites and the Main granite by the use of multivariate statistics. The Bobbejaankop granite appears as a more-differentaited rock carrying greater amounts of the incompatible elements than does the Main granite [af

Application of AC servo motor on the in-core neutron flux instrumentation system

International Nuclear Information System (INIS)

Du Xiaoguang; Wang Mingtao

2010-01-01

The application of ac servo motor in the In-Core Neutron Flux Instrumentation System is described. The hardware component of ac servo motor control system is different from the dc motor control system. The effect of two control system on the instrumentation system is compared. The ac servo motor control system can improve the accuracy of the motion control, optimize the speed control and increase the reliability. (authors)

When thin is sexy - neutron reflectometry instrumentation at the Australian replacement research reactor

International Nuclear Information System (INIS)

James, M.

2003-01-01

Full text: Neutron and X-ray reflectometry are techniques used to probe the structure of surfaces, thin-films or buried interfaces as well as processes occurring at surfaces and interfaces such as adsorption, adhesion and inter-diffusion. Applications cover adsorbed surfactant layers, self-assembled monolayers, biological membranes, electrochemical and catalytic interfaces, polymer coatings and photosensitive films. Contrast variation and selective deuteration of hydrogenous materials are important aspects of the neutron-based technique. Neutron reflectometry probes the structure of materials normal to the surface at depths of up to several thousand Angstroms, with an effective depth resolution of a few Angstroms. Neutron reflectometry experiments have been performed by a number of Australian researchers at overseas facilities for more than a decade, however this capability has previously been absent in this country. A neutron reflectometer has been recognised as one of the highest priority instruments to be constructed at the new 20MW research reactor facility at Lucas Heights (due for completion in 2006). In this presentation we report the design of the time-of-flight reflectometer to be constructed at the new research facility. The reflectometer will operate with a vertical scattering plane and thus be able to measure specular reflectometry from both solid and liquid samples. A series of disc choppers will enable the instrument resolution (ΔQ/Q) to be varied from 2% to > 15%. The detection system will consist of a 2-dimenional position sensitive detector that will also allow the measurement of off-specular reflectivity

Instrumental neutron activation analysis in environmental research

International Nuclear Information System (INIS)

Bruin, M. de.

1985-01-01

The main characteristics of instrumental neutron activation analysis (INAA),relevant for environmental research and monitoring, was reviewed and discussed-sensitivity, suitable for detection of many toxic elements, the low risks of contamination of element loss, lack of matrix effects, lack of light element interference except for 24 Na, capability for multi-element determination, comparatively low costs. A detailed description of the IRI analysis system for routine INAA is given. The system is based on the single comparator method of standartization to take full advantage of multi-element without preparation and use the trace element standards. Zinc was used as mono element standard, the element concentrations are calculated on the basis of 65 Zn and 69m Zn-activities. The irradiations were carried out in a thermal neutron flux of 1.10 13 n/cm 2 .s. The gamma spectra is converted into element concentrations using a set of dedicated software, performing the following functions: spectrum analysis and interpretation, comparison and combination of the intermediate results from different decay times, generation of the final report, bookkeeping of the results obtained. The main applications of the INAA system mentioned are: identification of sources of heavy metal air pollution using air filters or biological indicators such as mosses, lichens, toe-nails, bird feathers, molusks and waterplants; and study of the uptake and translocation of heavy element in plants. Special attention was paid to mathematical techniques for a reliable interpretation of the element concentration patterns observed in sets of lichen samples. Future developments in INAA in environmental science are briefly mentioned

Neutron Scattering Investigations of Correlated Electron Systems and Neutron Instrumentation

DEFF Research Database (Denmark)

Holm, Sonja Lindahl

are a unique probe for studying the atomic and molecular structure and dynamics of materials. Even though neutrons are very expensive to produce, the advantages neutrons provide overshadow the price. As neutrons interact weakly with materials compared to many other probes, e.g. electrons or photons...... contains antiferromagnetically coupled Cu2+ S = 1=2 ions forming truncated 24-spin cube clusters of linked triangles. The clusters in boleite afford a situation intermediate between molecular and bulk magnetism, accessible to both experiment and numerical theory, in which a spin liquid can be studied...... the impact of the time structure (pulse length and repetition frequency) choice for ESS are appended. McStas simulations of a low resolution cold powder diffractometer and high resolution thermal powder diffractometer with wavelength frame multiplication have been carried out for 20 different settings...

Optimization of instrumental neutron activation analysis for the within-bottle homogeneity study of reference materials of marine origin

International Nuclear Information System (INIS)

Silva, Daniel Pereira da

2017-01-01

The use of reference materials has been increasing in chemical analysis laboratories as its use is important for measurement validation in analytical chemistry. Such materials are generally imported, which require high financial investments in order to acquire them, and therefore it impacts on the difficulty to many national laboratories to use reference materials in their chemical analysis routine. Certification of reference materials is a complex process that assumes that the user is given appropriate assigned values of the properties of interests in the material. In this process, the homogeneity of the material must be checked. In this study, the within-bottle homogeneity study for the elements K, Mg, Mn, Na and V was performed for two reference materials of marine origin: the mussel reference material produced at the Neutron Activation Laboratory (LAN) of IPEN - CNEN/SP and an oyster tissue reference material produced abroad. For this purpose, the elements were determined in subsamples with masses varying between 1 and 250 mg by Instrumental Neutron Activation Analysis (INAA) and minimum sample intakes were estimated, ranging from 0.015 g for Na in the mussel reference material to 0.100 g for V in the two reference materials. (author)

Development of a neutron-polarizing device based on a quadrupole magnet and its application to a focusing SANS instrument

International Nuclear Information System (INIS)

Oku, Takayuki

2009-01-01

We have investigated suitable magnetic field distribution to polarize neutrons based only on the electromagnetic interaction between a neutron magnetic moment and magnetic field, and found out a quadrupole field was the most suitable among simple multipole fields. Then we constructed a quadrupole magnet with a Halbach magnetic circuit as the neutron polarizing device. A cold neutron polarizing experiment of the quadrupole magnet was performed at the beamline C3-1-2-1 (NOP) of JRR-3 at JAEA. By passing through the aperture of the quadrupole magnet, positive and negative polarity neutrons are accelerated in opposite directions and spatially separated. Therefore, we extracted the one-spin component and analyzed its polarization degree. As a result very high neutron polarization degree P=0.9993±0.0025 was obtained. Then the quadrupole magnet was installed into the polarized neutron focusing geometry SANS instrument SANS-J-II of JRR-3. The instrument performance was enhanced by about 10 times compared with the case with the magnetic supermirror as the neutron polarizing device. The details are shown and discussed. (author)

Recent developments in X-ray and neutron small-angle scattering instrumentation and data analysis

International Nuclear Information System (INIS)

Schelten, J.

1978-01-01

The developments in instrumentation and data analysis that have occurred in the field of small-angle X-ray and neutron scattering since 1973 are reviewed. For X-rays, the cone camera collimation was invented, synchrotrons and storage rings were demonstrated to be intense sources of X-radiation, and one- and two-dimensional position-sensitive detectors were interfaced to cameras with both point and line collimation. For neutrons, the collimators and detectors on the Juelich and Grenoble machines were improved, new D11-type instruments were built or are under construction at several sites, double-crystal instruments were set up, and various new machines have been proposed. Significant progress in data analysis and evaluation has been made through application of mathematical techniques such as the use of spline functions, error minimization with constraints, and linear programming. Several special experiments, unusual in respect to the anisotropy of the scattering pattern, gravitational effects, moving scatterers, and dynamic fast time slicing, are discussed. (Auth.)

Support for cold neutron utilization

International Nuclear Information System (INIS)

Lee, Kye Hong; Han, Young Soo; Choi, Sungmin; Choi, Yong; Kwon, Hoon; Lee, Kwang Hee

2012-06-01

- 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

Preliminary study on zinc-carbon battery performance by using neutron tomography

International Nuclear Information System (INIS)

Abdul Aziz Mohamed; Nor Abidin Ashari; Mohd Zaid Abdullah; Junita Mohamad Saleh; Azraf Azman; Megat Harun AlRashid Megat Ahmad; Rafhayudi Jamro

2008-08-01

This paper describes on the discharging characteristic of zinc-carbon batteries (dry cells) by using a neutron imaging technique called a monochromatic neutron tomography. Experiment was conducted on the Nuclear Malaysia neutron tomography prototype instrument which based on 1-dimensional position sensitive neutron detector. The instrument is constructed at the small angle neutron scattering (SANS) beam line built at the one of the beam ports of TRIGA MARK II Research reactor, Malaysian Nuclear Agency, Bangi, Selangor. The main aim of this preliminary experiment was to test the instrument capability on a real industrial component. It was also aimed to understand structural and chemical changes of these battery particles after experiencing a discharging process. In this preliminary work, new and used batteries used were the products of Eveready company. (Author)

Mercury determination in dentist's hair and nails by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Mazzilli, B.; Munita, C.S.

1986-01-01

The mercury in scalp hair and fingernails of a group of dentists who usually handle with this toxic element in their profession is determined. The results were obtained by instrumental neutron activation analysis. The experimental procedure was based on the evaluation of the 197 Hg photopeak area, whose half life is 65h. After at a neutron fluxo of 5x10 12 n.cm -2 .sec -1 , the activity of the samples were measured by using a solid state Ge (Li) detector coupled to a 4.096 channel pulse height analyser. (M.A.C.) [pt

Multielement determination in some egyptian vegetables by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Tadros, N.A.; Abdel-Fattah, A.A.; Sanad, W.A.

1999-01-01

Nondestructive instrumental neutron activation analysis (INAA) technique, with thermal neutrons, has been applied for multielement determination of major, trace and ultra trace elements in eleven types of the public public egyptian, edible vegetables, namely dill, moulokhyia, okra negro bean, parsley, green pea, grape leaves, spinach, mint, celery and salad chervil, cultivated and collected from El-Maadi, Cairo, E G. Concentrations of Na, K, Ca, Sc, Cr, Fe, Co, Ni, Zn, Rb, Zr, Nb, Mo, Sb, Cs, Ba, La, Ce, Tb, Yb, Hf, Ta, Th and U were determined. The standard reference materials (SRM's) G-2, J G-1 and MAG-1, provided from IAEA, were used, and high accuracy of the work was assured. The results were discussed

Determination of rare earth elements in sea sediments from the Cuban northwestern coast by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Capote Rodriguez, G.; Perez Zayas, G.; Pena Fortes, B.; Diaz Riso, O.; Hernandez Rivero, A.T.

1998-01-01

The multielemental characterization of sea sediments from an important Cuban coast was performed using instrumental Neutron activation analysis. The obtained results shown an impoverishment of in the studied zone, in comparison with the data taken from other Cuban coaster zones

Code of practice for in-core instrumentation for neutron fluence rate (flux) measurements in power reactors

International Nuclear Information System (INIS)

Anon.

1982-01-01

This standard applies to in-core (on-line) neutron detectors and instrumentation which is designed for safety, information or control purposes. It also applies to components in so far as these components are contained within the primary envelope of the reactor. The detector types usually used are dc ionization chambers and self-powered neutron detectors

Instrumental neutron activities analysis of Marrubium vulgare L., a valuable medicinal herb

Energy Technology Data Exchange (ETDEWEB)

Nedjimi, Bouzid [Djelfa Univ. (Algeria). Lab. of Exploration and Valorization of Steppe Ecosystem; Beladel, Brahim [Djelfa Univ. (Algeria). Dept. of Physics

2016-08-01

Twenty two chemical elements were identified by Instrumental neutron activation analysis in Marrubium vulgare (Lamiaceae) a traditional medicine plant, used indigenously in Mediterranean basin to cure several diseases. The precision of the results was assessed by analyzing the certified reference material GBW 07605 (GSV-4) Tea leaves. Results showed that K was the dominant chemical element in studied plant (4.40%). The Ca and Fe mass fractions were also relatively high. However potential toxic elements in this Lamiaceae plant were within the safety limits suggested by WHO/FAO.

Application of instrumental neutron activation analysis to study ceramic fragments from Damascus Castle site, Syria

International Nuclear Information System (INIS)

Bakraji, E.H.

2005-01-01

Thirty-three archaeological ceramic fragment samples from Damascus Castle archaeological site, Damascus city, Syria, were analyzed using instrumental neutron activation analysis (INAA). 36 elements were determined. These elemental concentrations have been processed using two multivariate statistical methods, cluster and factor analysis in order to determine similarities and correlation between the various samples. Factor analysis confirms that 84.8% of the ceramics samples classified by cluster analysis are correctly classified by cluster analysis. The results provided persuasive evidence that Castle pottery used at least four different clay sources. Moreover, by means of systematic local analysis it will be clear whether these sources are local or not. (author)

Neutron Measurement Instrumentation Development at KIT for the European ITER TBM

Energy Technology Data Exchange (ETDEWEB)

Klix, A.; Fischer, U.; Raj, P.; Reimann, Th.; Szalkai, D.; Tian, K. [Association KIT-EURATOM, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen (Germany); Angelone, M. [Associazione ENEA-EURATOM sulla Fusione, ENEA C.R., I-00044 Frascati (Italy); Gehre, D. [Technical University of Dresden, D-01069 Dresden (Germany); Lyoussi, A. [CEA, DEN, DER, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, F-13108 St-Paul-Lez-Durance (France)

2015-07-01

Fusion power reactors will rely on the internal production of the fuel tritium from lithium in the tritium breeding blanket. Test Blanket Modules (TBM) will be installed in ITER with the aim to investigate the nuclear performance of different breeding blanket designs. Currently there is no fully qualified nuclear instrumentation available for the measurement of neutron fluxes and tritium production rates which would be able to withstand the harsh environment conditions in the TBM such as high temperature (>400 deg. C) and, depending on the operation scenario, intense radiation levels. As partner of the European Consortium on Nuclear Data and Measurement Techniques in the framework of several F4E specific grants and contracts, KIT and ENEA have jointly studied the possibility to develop and test detectors suitable to operate in ITER-TBMs. Here we present an overview of ongoing work on three types of neutron flux monitors under development for the TBMs with focus on the KIT activities. A neutron activation system (NAS) with pneumatic sample transport could provide absolute neutron flux measurements in selected positions. A test system for investigating activation materials with short half-lives was constructed at the DT neutron generator laboratory of Technical University of Dresden to investigate the neutronics aspects. Several irradiations have been performed with focus on the simultaneous measurement of the extracted activated probes. An engineering assessment of a TBM NAS in the conceptual design phase has been done which considered issues of design requirements and integration. Last but not least, a mechanical test bench is under construction at KIT which will address issues of driving the activation probes, solutions for loading the system etc. experimentally. Self-powered neutron detectors (SPND) are widely applied in fission reactor monitoring, and the commercially available SPNDs are sensitive to thermal neutrons. We are investigating novel materials for

The Neutron, a Tool and an Object for Fundamental and Nuclear Physics Studies

CERN Multimedia

CERN. Geneva

2004-01-01

The Institut Laue-Langevin (ILL) is an international research institute which operates the currently most powerful source of neutrons in the world, a 58 MW reactor. The neutron beams provided by the reactor feed a broad range of instruments which are dedicated to a wide variety of research activities. The majority of instruments are dedicated to the study of solid-state physics, materials science, chemistry, the biosciences, and earth sciences. However, nuclear and low energy particle physics studies are also vigorously pursued with the aid of neutrons. The talk will mainly concentrate on this latter aspect. We make use of hot, thermal, cold, and ultra-cold neutrons with velocities of between a few kilometers and a few meters per second, corresponding to kinetic energies in the electronvolt-to-nanoelectronvolt range. It will be briefly discussed how thermal neutrons can be used to investigate the structure and behavior of nuclei by generating excited nuclear states. The main part of the talk will be dedicated...

Instrument intercomparison in the pulsed neutron fieldsat the CERN HiRadMat facility

CERN Document Server

Aza, E; Cassell, C; Charitonidis, N; Harrouch, E; Manessi, G P; Pangallo, M; Perrin, D; Samara, E; Silari, M

2014-01-01

An intercomparison of the performances of active neutron detectors was carried out in pulsed neutron fi elds in the new HiRadMat facility at CERN. Five detectors were employed: four of them (two ionization chambers and two rem counters) are routinely employed in the CERN radiation monitoring system, while the fi fth is a novel instrument, called LUPIN, speci fi cally conceived for applications in pulsed neutron fi elds. The measurements were performed in the stray fi eld generated by a proton beam of very short duration with momentum of 440 GeV/c impinging on a dump. The beam intensity was steadily increased during the experiment by more than three orders of magnitude, with an H*(10) due to neutrons at the detector reference positions varying between a few nSv per burst and a few m Sv per burst, whereas the gamma contribution to the total H*(10) was negligible. The aim of the experiment was to evaluate the linearity of the detector response in extreme pulsed conditions as a function of the neutron burst in- t...

FaNGaS: a New Instrument for Fast Neutron Gamma Spectroscopy at FRM II Research Reactor at Garching

Energy Technology Data Exchange (ETDEWEB)

Randriamalala, T.; Rossbach, M.; Genreith, C. [Institute of Energy and Climate Research, IEK-6: Nuclear Waste and Reactor Safety Fuel Cycle, Forchungszentrum Juelich GmbH in der Helmholtz-Gemeinshaft, 52428 Juelich (Germany); Revay, Zs.; Kudejova, P.; Soellradl, S.; Wagner, F.M. [Heinz Maier-Leibnitz Zentrum - MLZ, Technische Universitaet Muenchen, Lichtenbergstrasse 1, 85748 Garching (Germany)

2015-07-01

For the identification and quantification of actinides in radioactive packages, the non-destructive method of Prompt-Gamma Activation Analysis (PGAA) is applied. To investigate the inelastic (n, n 'γ) scattering, a new instrumentation was installed at the FRM II research reactor. It is designed to exploit the 10{sup 8} cm{sup -2}s{sup -1} neutrons at an average neutron energy of 1.9 MeV delivered by the SR10 beam line. The outgoing prompt γ-rays are measured utilizing a 50% efficiency HPGe detector. Since the cross sections are expected to be low for such a process, two related factors had to be taken into account for the design of the instrumentation: the high beam intensity at the sample position and the high signal-to-background ratio seen by the detector. Eventual low energy neutrons due to the multiple scatterings through the beam line can be minimized using collimators in the beam tube. This has also an effect to a prior neutrons and photons background reduction of the experimental environment. A higher efficiency of the counting can be achieved by the lowering of background at the detector. In this case, a heavy shielding for both neutrons and photons, is designed around the detector while optimizing the sample-detector distance. Monte-Carlo simulation studies were conducted to effectively design the fast neutron beam collimators and the detector shield. A detailed description of the setup characterization and results from simulations and experimental measurements will be discussed through this contribution. (authors)

Instrumental neutron activation analysis as a routine method for rock analysis

International Nuclear Information System (INIS)

Rosenberg, R.J.

1977-06-01

Instrumental neutron activation methods for the analysis of geological samples have been developed. Special emphasis has been laid on the improvement of sensitivity and accuracy in order to maximize tha quality of the analyses. Furthermore, the procedures have been automated as far as possible in order to minimize the cost of the analysis. A short review of the basic literature is given followed by a description of the principles of the method. All aspects concerning the sensitivity are discussed thoroughly in view of the analyst's possibility of influencing them. Experimentally determined detection limits for Na, Al, K, Ca, Sc, Cr, Ti, V, Mn, Fe, Ni, Co, Rb, Zr, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Lu, Hf, Ta, Th and U are given. The errors of the method are discussed followed by actions taken to avoid them. The most significant error was caused by flux deviation, but this was avoided by building a rotating sample holder for rotating the samples during irradiation. A scheme for the INAA of 32 elements is proposed. The method has been automated as far as possible and an automatic γ-spectrometer and a computer program for the automatic calculation of the results are described. Furthermore, a completely automated uranium analyzer based on delayed neutron counting is described. The methods are discussed in view of their applicability to rock analysis. It is stated that the sensitivity varies considerably from element to element and instrumental activation analysis is an excellent method for the analysis of some specific elements like lanthanides, thorium and uranium but less so for many other elements. The accuracy is good varying from 2% to 10% for most elements. Instrumental activation analysis for most elements is rather an expensive method there being, however, a few exceptions. The most important of these is uranium. The analysis of uranium by delayed neutron counting is an inexpensive means for the analysis of large numbers of samples needed for

μ-TPC: a future standard instrument for low energy neutron field characterization

International Nuclear Information System (INIS)

Maire, D.; Lebreton, L.; Petit, M.; Billard, J.; Bourrion, O.; Bosson, G.; Guillaudin, O.; Lamblin, J.; Mayet, F.; Medard, J.; Muraz, J.F.; Richer, J.P.; Riffard, Q.; Santos, D.

2013-06-01

In order to measure energy of neutron fields, with energy ranging from 8 keV to 1 MeV, a new primary standard is being developed at the IRSN (Institute for Radioprotection and Nuclear Safety). This project, μ-TPC (Micro Time Projection Chamber), carried out in collaboration with the LPSC (Laboratoire de Physique Subatomique et de Cosmologie), is based on the nucleus recoil detector principle. The instrument will be presented with the associated method to measure the neutron energy. This article will emphasize the proton energy calibration procedure and energy measurements of a neutron field produced at 127 keV on the IRSN facility AMANDE. Finally the COMIMAC device, dedicated to the calibration, will be described. This original device, developed at the LPSC, is able to produce proton and electron beams with an accurate energy ranging from 1 keV to 50 keV. (authors)

New highly sensitive method of simultaneous instrumental neutron activation determination of 12 microelements in vine

International Nuclear Information System (INIS)

Shoniya, N.I.

1977-01-01

The main principles and methods of simultaneous multi-element instrumental neutron activation determination of microelements in vine seeds are presented. The methods permit to carry out quantitative evaluation for every single corn of the seeds. It is shown that the method of instrumental neutron activation analysis with the utilization of a semiconductor spectrometer of high resolution and mini electronic computer permit to carry out serial determinations of 12 microelements in the individual corns of vine seeds of different sorts. This method will permit to determine the missing or excess content of this or that biologically important microelement in soils, plants, fruit and genetic material - seeds, and so to determine the optimum conditions of growing plants by applying microelement fertilizers as extra nutrient means

Vertical distribution of elements in non-polluted estuarine sediments determined by neutron induced prompt gamma-ray and instrumental neutron activation analyses

International Nuclear Information System (INIS)

Kuno, A.; Sampei, K.; Matsuo, M.; Sawahata, H.

1999-01-01

Neutron induced prompt gamma-ray analysis (PGA) and instrumental neutron activation analysis (INAA) have been applied to the sediments collected from the Yasaka River estuary in Oita Prefecture, Japan. The vertical distribution of 33 elements in the sediments has been determined and compared with that in more polluted estuarine sediments. While the S content increased with increasing depth because of a sulphide accumulation under reducing condition, the increase in sulphide-forming elements such as Ag, Cd, Co and Zn was not observed in the deeper section of the Yasaka River estuarine sediments. (author)

Neutron xyz - polarization analysis at a time-of-flight instrument

Energy Technology Data Exchange (ETDEWEB)

Ehlers, Georg [ORNL; Stewart, John Ross [ISIS Facility, Rutherford Appleton Laboratory; Andersen, Ken [ESS

2015-01-01

When implementing a dedicated polarization analysis setup at a neutron time-of-flight instrument with a large area detector, one faces enormous challenges. Nevertheless, significant progress has been made towards this goal over the last few years. This paper addresses systematic limitations of the traditional method that is used to make these measurements, and a possible strategy to overcome these limitations. This will be important, for diffraction as well as inelastic experiments, where the scattering occurs mostly out-of-plane.

Studies on elemental analysis of widely consumed traditional herbs in Libya by ko instrumental neutron activation analysis

International Nuclear Information System (INIS)

Abugassa, I. O.; Abunawael, M. E.

2012-12-01

Herbs are accepted as an alternative medicine for specific treatment of illness of among different ethnic groups worldwide. It is vital to know the contents of these herbs used in Libya were analysed by k-0 instrumental neutron activation analysis. A total of 32 trace and major elements (Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Mo, Na, Nd, Rb, Sb, Sc, Se, Sm, Sr, Tb, Th, Tm, U, Yb and Zn) were determined. The concentration of elements varied depending on the origin of the herb. The study showed that the toxic elements found in the samples were below the levels prescribed by health regulations. The method was justified by analyzing two SRM. All the results are in good agreement with the certified values. (Author)

Multielement analysis of rice flour-unpolished reference material by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Suzuki, Shogo; Hirai, Shoji

1990-01-01

Trace elements in NIES certified reference material No. 10-a∼10-c Rice Flour-Unpolished, prepared by the National Institute for Environmental Studies of Japan (NIES), were determined by instrumental neutron activation analysis (INAA). A set of three samples with different Cd concentration levels was subjected to analyses. Portions of each sample (ca. 200∼1000 mg) were irradiated, either with thermal neutrons without cadmium filter or with epithermal neutrons with cadmium filter, in the Musashi Institute of Technology Research Reactor (MITRR). The activated samples were analyzed by the three methods; conventional γ-ray spectrometry using a coaxial Ge detector, anticoincidence counting spectrometry, and coincidence counting spectrometry using a coaxial Ge detector and a well type NaI(Tl) detector. Concentrations of 26∼28 elements were determined by these methods. The values obtained for many elements, except for Mg and K, were in good agreement with those of the NIES certified and reference. Concentrations of 10 elements (S, Sc, V, Ag, Sb, Cs, Ba, La, Sm, Th), whose certified or reference values are not available from NIES, were also determined in this work. (author)

Calibration of the GNU and HSREM neutron survey instruments

International Nuclear Information System (INIS)

Eakins, J.S.; Hager, L.G.; Leake, J.W.; Mason, R.S.; Tanner, R.J.

2017-01-01

Two innovative designs of neutron survey instrument have recently been developed to estimate ambient dose equivalent in the workplace: the GNU has an improved energy-independence of response in the meV to TeV range; the HSREM is a comparatively lightweight device covering the meV to 10 MeV range. Both designs offer good detection sensitivity, allowing measurements to be made efficiently and thereby minimizing the exposure to their users. Prototypes of both devices have been constructed and exposed to sets of well-characterized reference fields: the resulting measured responses are presented and discussed here, compared against comprehensive Monte Carlo data.

Calibration of the GNU and HSREM neutron survey instruments

Energy Technology Data Exchange (ETDEWEB)

Eakins, J.S., E-mail: jonathan.eakins@phe.gov.uk [Public Health England, CRCE, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom); Hager, L.G. [Public Health England, CRCE, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom); Leake, J.W.; Mason, R.S. [Sherwood Nutec Scientific Ltd., Kent (United Kingdom); Tanner, R.J. [Public Health England, CRCE, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom)

2017-04-21

Two innovative designs of neutron survey instrument have recently been developed to estimate ambient dose equivalent in the workplace: the GNU has an improved energy-independence of response in the meV to TeV range; the HSREM is a comparatively lightweight device covering the meV to 10 MeV range. Both designs offer good detection sensitivity, allowing measurements to be made efficiently and thereby minimizing the exposure to their users. Prototypes of both devices have been constructed and exposed to sets of well-characterized reference fields: the resulting measured responses are presented and discussed here, compared against comprehensive Monte Carlo data.

Neutrons and Nuclear Engineering

International Nuclear Information System (INIS)

Ekkebus, Allen E.

2007-01-01

Oak Ridge National Laboratory hosted two workshops in April 2007 relevant to nuclear engineering education. In the Neutron Stress, Texture, and Phase Transformation for Industry workshop (http://neutrons.ornl.gov/workshops/nst2/), several invited speakers gave examples of neutron stress mapping for nuclear engineering applications. These included John Root of National Research Council of Canada, Mike Fitzpatrick of the UK's Open University, and Yan Gao of GE Global Research on their experiences with industrial and academic uses of neutron diffraction. Xun-Li Wang and Camden Hubbard described the new instruments at ORNL that can be used for such studies. This was preceded by the Neutrons for Materials Science and Engineering educational symposium (http://neutrons.ornl.gov/workshops/edsym2007). It was directed to the broad materials science and engineering community based in universities, industry and laboratories who wish to learn what the neutron sources in the US can provide for enhancing the understanding of materials behavior, processing and joining. Of particular interest was the presentation of Donald Brown of Los Alamos about using 'Neutron diffraction measurements of strain and texture to study mechanical behavior of structural materials.' At both workshops, the ORNL neutron scattering instruments relevant to nuclear engineering studies were described. The Neutron Residual Stress Mapping Facility (NRSF2) is currently in operation at the High Flux Isotope Reactor; the VULCAN Engineering Materials Diffractometer will begin commissioning in 2008 at the Spallation Neutron Source. For characteristics of these instruments, as well as details of other workshops, meetings, capabilities, and research proposal submissions, please visit http://neutrons.ornl.gov. To submit user proposals for time on NRSF2 contact Hubbard at hubbardcratornl.gov

Instrumental aspects

Directory of Open Access Journals (Sweden)

Qureshi Navid

2017-01-01

Full Text Available Every neutron scattering experiment requires the choice of a suited neutron diffractometer (or spectrometer in the case of inelastic scattering with its optimal configuration in order to accomplish the experimental tasks in the most successful way. Most generally, the compromise between the incident neutron flux and the instrumental resolution has to be considered, which is depending on a number of optical devices which are positioned in the neutron beam path. In this chapter the basic instrumental principles of neutron diffraction will be explained. Examples of different types of experiments and their respective expectable results will be shown. Furthermore, the production and use of polarized neutrons will be stressed.

Design of a TOF-SANS instrument for the proposed long wavelength target station at the spallation neutron source

International Nuclear Information System (INIS)

Thiyagarajan, P.; Littrell, K.; Seeger, P.A.

2001-01-01

We have designed a versatile high-throughput SANS instrument [Broad Range Intense Multipurpose SANS (BRIMS)] for the proposed Long Wavelength Target Station at the SNS by using acceptance diagrams and the Los Alamos NISP Monte Carlo simulation package. This instrument has been fully optimized to take advantage of the 10 Hz source frequency (broad wavelength bandwidth) and the cold neutron spectrum from a tall coupled solid methane moderator (12 cm x 20 cm). BRIMS has been designed to produce data in a Q range spanning from 0.0025 to 0.7 A -1 in a single measurement by simultaneously using neutrons with wavelengths ranging from 1 to 14.5 A in a time of flight mode. A supermirror guide and bender assembly is employed to separate and redirect the useful portion of the neutron spectrum with λ>1 A, by 2.3deg away from the direct beam containing high energy neutrons and γ rays. The effects of various collimation choices on count rate, resolution and Q min have been characterized using spherical particle and delta function scatterers. The overall performance of BRIMS has been compared with that of the best existing reactor-based SANS instrument D22 at ILL. (author)

Development of Cold Neutron Activation Station at HANARO Cold Neutron Source

International Nuclear Information System (INIS)

Sun, G. M.; Hoang, S. M. T.; Moon, J. H.; Chung, Y. S.; Cho, S. J.; Lee, K. H.; Park, B. G.; Choi, H. D.

2012-01-01

A new cold neutron source at the HANARO Research Reactor had been constructed in the framework of a five-year project, and ended in 2009. It has seven neutron guides, among which five guides were already allocated for a number of neutron scattering instruments. A new two-year project to develop a Cold Neutron Activation Station (CONAS) was carried out at the two neutron guides since May 2010, which was supported by the program of the Ministry of Education, Science and Technology, Korea. Fig. 1 shows the location of CONAS. CONAS is a complex facility including several radioanalytical instruments utilizing neutron capture reaction to analyze elements in a sample. It was designed to include three instruments like a CN-PGAA (Cold Neutron - Prompt Gamma Activation Analysis), a CN-NIPS (Cold Neutron - Neutron Induced Pair Spectrometer), and a CN-NDP (Cold Neutron - Neutron-induced prompt charged particle Depth Profiling). Fig. 2 shows the conceptual configuration of the CONAS concrete bioshield and the instruments. CN-PGAA and CN-NIPS measure the gamma-rays promptly emitted from the sample after neutron capture, whereas CN-NDP is a probe to measure the charged particles emitted from the sample surface after neutron capture. For this, we constructed two cold neutron guides called CG1 and CG2B guides from the CNS

Certification of biological reference materials by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Lanjewar, Mamata R.; Lanjewar, R.B.

2014-01-01

A multielemental instrumental neutron activation analysis (INAA) method by short and long irradiation has been employed for the determination of 21 minor and trace elements in two standard Reference Materials P-RBF and P-WBF from Institute of Radioecology and Applied Nuclear Techniques ,Czechoslovakia. Also some biological standards such as Bowen's kale, cabbage leaves (Poland) including wheat and rice flour samples of local origin were analysed. It is suggested that INAA is an ideal method for the certification of Reference Materials of Biological Matrices. (author)

Neutrons for Catalysis: A Workshop on Neutron Scattering Techniques for Studies in Catalysis

International Nuclear Information System (INIS)

Overbury, Steven H.; Coates, Leighton; Herwig, Kenneth W.; Kidder, Michelle

2011-01-01

This report summarizes the Workshop on Neutron Scattering Techniques for Studies in Catalysis, held at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) on September 16 and 17, 2010. The goal of the Workshop was to bring experts in heterogeneous catalysis and biocatalysis together with neutron scattering experimenters to identify ways to attack new problems, especially Grand Challenge problems in catalysis, using neutron scattering. The Workshop locale was motivated by the neutron capabilities at ORNL, including the High Flux Isotope Reactor (HFIR) and the new and developing instrumentation at the SNS. Approximately 90 researchers met for 1 1/2 days with oral presentations and breakout sessions. Oral presentations were divided into five topical sessions aimed at a discussion of Grand Challenge problems in catalysis, dynamics studies, structure characterization, biocatalysis, and computational methods. Eleven internationally known invited experts spoke in these sessions. The Workshop was intended both to educate catalyst experts about the methods and possibilities of neutron methods and to educate the neutron community about the methods and scientific challenges in catalysis. Above all, it was intended to inspire new research ideas among the attendees. All attendees were asked to participate in one or more of three breakout sessions to share ideas and propose new experiments that could be performed using the ORNL neutron facilities. The Workshop was expected to lead to proposals for beam time at either the HFIR or the SNS; therefore, it was expected that each breakout session would identify a few experiments or proof-of-principle experiments and a leader who would pursue a proposal after the Workshop. Also, a refereed review article will be submitted to a prominent journal to present research and ideas illustrating the benefits and possibilities of neutron methods for catalysis research.

Neutrons for Catalysis: A Workshop on Neutron Scattering Techniques for Studies in Catalysis

Energy Technology Data Exchange (ETDEWEB)

Overbury, Steven {Steve} H [ORNL; Coates, Leighton [ORNL; Herwig, Kenneth W [ORNL; Kidder, Michelle [ORNL

2011-10-01

This report summarizes the Workshop on Neutron Scattering Techniques for Studies in Catalysis, held at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) on September 16 and 17, 2010. The goal of the Workshop was to bring experts in heterogeneous catalysis and biocatalysis together with neutron scattering experimenters to identify ways to attack new problems, especially Grand Challenge problems in catalysis, using neutron scattering. The Workshop locale was motivated by the neutron capabilities at ORNL, including the High Flux Isotope Reactor (HFIR) and the new and developing instrumentation at the SNS. Approximately 90 researchers met for 1 1/2 days with oral presentations and breakout sessions. Oral presentations were divided into five topical sessions aimed at a discussion of Grand Challenge problems in catalysis, dynamics studies, structure characterization, biocatalysis, and computational methods. Eleven internationally known invited experts spoke in these sessions. The Workshop was intended both to educate catalyst experts about the methods and possibilities of neutron methods and to educate the neutron community about the methods and scientific challenges in catalysis. Above all, it was intended to inspire new research ideas among the attendees. All attendees were asked to participate in one or more of three breakout sessions to share ideas and propose new experiments that could be performed using the ORNL neutron facilities. The Workshop was expected to lead to proposals for beam time at either the HFIR or the SNS; therefore, it was expected that each breakout session would identify a few experiments or proof-of-principle experiments and a leader who would pursue a proposal after the Workshop. Also, a refereed review article will be submitted to a prominent journal to present research and ideas illustrating the benefits and possibilities of neutron methods for catalysis research.

Instrumental neutron activation analysis of soil sample

International Nuclear Information System (INIS)

Abdul Khalik Haji Wood.

1983-01-01

This paper describes the analysis of soil samples collected from 5 different location around Sungai Lui, Kajang, Selangor, Malaysia. These sample were taken at 22-24 cm from the top of the ground and were analysed using the techniques of Instrumental Neutron Activation Analysis (INAA). The analysis on soil sample taken above 22-24 cm level were done in order to determine if there is any variation in elemental contents at different sampling levels. The results indicate a wide variation in the contents of the samples. About 30 elements have been analysed. The major ones are Na, I, Cl, Mg, Al, K, Ti, Ca and Fe. Trace elements analysed were Ba, Sc, V, Cr, Mn, Ga, As, Zn, Br, Rb, Co, Hf, Zr, Th, U, Sb, Cs, Ce, Sm, Eu, Tb, Dy, Yb, Lu and La. (author)

A new instrumental set-up for polarized neutron scattering experiments

International Nuclear Information System (INIS)

Schmidt, Wolfgang; Ohl, Michael

2005-01-01

Neutron scattering with polarization analysis is a powerful tool to determine magnetic structures and excitations. A common setup is to mount the sample at the center of a Helmholtz-type coil which can provide a magnetic field of any direction at the sample position and also a guide field along the neutron flight paths around the sample. Recent experiments showed quite a high demand for measurements at low momentum transfers. For the corresponding low scattering angles air scattering gives rise to a very large background. For this reason we have extended the standard setup to a combination of a large vacuum tank surrounded by electrical coils. The vacuum tank eliminates the air scattering and we can use the polarization analysis down to the lowest accessible momentum transfers. The coils themselves also show some new features: In contrary to the classic (symmetric) coil distribution we use an asymmetric setup which gives the advantage of a larger scattering window. Due to a more sophisticated current distribution this modified coil arrangement needs not to be rotated for different scattering conditions. The whole set-up will soon be available at IN12, a cold neutrons three-axis spectrometer operated by FZ Juelich in collaboration with CEA Grenoble as a CRG-B instrument at the Institut Laue Langevin in Grenoble

Development of new methods for studying nanostructures using neutron scattering

International Nuclear Information System (INIS)

Pynn, Roger

2016-01-01

The goal of this project was to develop improved instrumentation for studying the microscopic structures of materials using neutron scattering. Neutron scattering has a number of advantages for studying material structure but suffers from the well-known disadvantage that neutrons' ability to resolve structural details is usually limited by the strength of available neutron sources. We aimed to overcome this disadvantage using a new experimental technique, called Spin Echo Scattering Angle Encoding (SESAME) that makes use of the neutron's magnetism. Our goal was to show that this innovation will allow the country to make better use of the significant investment it has recently made in a new neutron source at Oak Ridge National Laboratory (ORNL) and will lead to increases in scientific knowledge that contribute to the Nation's technological infrastructure and ability to develop advanced materials and technologies. We were successful in demonstrating the technical effectiveness of the new method and established a baseline of knowledge that has allowed ORNL to start a project to implement the method on one of its neutron beam lines.

About the study of irradiation effects on in-core instrumentation

International Nuclear Information System (INIS)

Angelino, G.

1972-01-01

The knowledge of in-core instrumentation performances is a very important item when irradiations of technological interest are concerned. When measurement of small changes in mechanical or thermal properties is of major importance, the effect of neutron and gamma irradiation on various transducers must be thoroughly evaluated. A rig mock-up was irradiated in the Triga Mark II Reactor of the Pavia University to assess the possibility of carrying out a study on irradiation effects on in-core instrumentation. Data on neutron flux distribution and γ-heating effect were collected from this preliminary experiment; at the same time a complete check was performed on rig assembling procedure, on the behaviour under operating conditions, and on the reactor loading and unloading operations. (author)

Beam Instrumentation for the Spallation Neutron Source Ring

International Nuclear Information System (INIS)

Witkover, R. L.; Cameron, P. R.; Shea, T. J.; Connolly, R. C.; Kesselman, M.

1999-01-01

The Spallation Neutron Source (SNS) will be constructed by a multi-laboratory collaboration with BNL responsible for the transfer lines and ring. The 1 MW beam power necessitates careful monitoring to minimize un-controlled loss. This high beam power will influence the design of the monitors in the high energy beam transport line (HEBT) from linac to ring, in the ring, and in the ring-to-target transfer line (RTBT). The ring instrumentation must cover a 3-decade range of beam intensity during accumulation. Beam loss monitoring will be especially critical since un-controlled beam loss must be kept below 10 -4 . A Beam-In-Gap (BIG) monitor is being designed to assure out-of-bucket beam will not be lost in the ring

Neutron dosimetry - A review

Energy Technology Data Exchange (ETDEWEB)

Baum, J W

1955-03-29

This review summarizes information on the following subjects: (1) physical processes of importance in neutron dosimetry; (2) biological effects of neutrons; (3) neutron sources; and (4) instruments and methods used in neutron dosimetry. Also, possible improvements in dosimetry instrumentation are outlined and discussed. (author)

Uses of instrumental neutron activation analysis (INAA) for lichen as bio indicators of environmental contamination

International Nuclear Information System (INIS)

Arribere, M.; Guevara, S.R.; Calvelo, S.

1994-01-01

Three species of epiphytic lichens were sampled at NW Patagonia, Argentina, from urban and peripherical forest area environments Sixty lichen samples were analysed individually by Instrumental Neutron Activation Analysis (INAA). The elements present in the samples were determined by parametric methods at the Neutron Activation Laboratory at Centro Atomico Bariloche, Argentina. All concentration values were normalized to Al concentration. The average normalized concentrations for each element, discriminated by species and environment, are presented in this work. (author). 11 refs, 6 tabs

Instrumental neutron activation analysis in environmental studies of trace elements

International Nuclear Information System (INIS)

Salmon, L.

1975-06-01

The application of a routine instrumental nuclear method is described in relation to environmental surveys and studies. A working rather than formal review is made of the techniques applied with particular reference to the data processing methods involved. The elements measured by instrumental activation analysis were: Ag, Al, As, Au, Ba, Br, Ca, Ce, Cl, Cd, Co, Cr, Cs, Cu, Fe, Hg, I, In, La, Mn, Na, Ni, Pb, Rb, Sb, Sc, Se, Th, Ti, U, V, W, Zn. (author)

Study on air pollution monitoring in Korea using low volume air sampler by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Yong Sam Chung; Jong Hwa Moon, Young Ju Chung; Seung Yeon Cho; Sang Hun Kang

1999-01-01

The aim of this research was to enhance the use of nuclear analytical techniques for air pollution studies and to study the feasibility of the use of instrumental neutron activation analysis (INAA) as a routine monitoring tool to reveal environmental pollution sources. For the collection of air particulate samples, the Gent stacked filter unit, low volume sampler with Nucleopore membrane filters were used. Trace elements in samples collected at two suburban residential sites, Taejon and Wonju city in the Republic of Korea, were analyzed by INAA. Variations of the elemental concentrations were measured monthly and the enrichment factors were calculated for the fine (< 2 μm EAD) and coarse size (2-10 μm EAD) fractions. The analytical data were treated statistically to estimate the relationship between the two variables, the concentrations of elements and the total suspended particulate matter. The results were used to describe the emission source and their correlation. (author)

Studies of the dynamic properties of materials using neutron scattering

International Nuclear Information System (INIS)

Lovesey, S.W.; Windsor, C.G.

1985-09-01

The dynamic properties of materials using the neutron scattering technique is reviewed. The basic properties of both nuclear scattering and magnetic scattering are summarized. The experimental methods used in neutron scattering are described, along with access to neutron sources, and neutron inelastic instruments. Applied materials science using inelastic neutron scattering; rotational tunnelling of a methyl group; molecular diffusion from quasi-elastic scattering; and the diffusion of colloidal particles and poly-nuclear complexes; are also briefly discussed. (U.K.)

Instrumental neutron activation analysis of brewer's yeast

International Nuclear Information System (INIS)

Bergerioux, C.; Zikovsky, L.

1978-01-01

Instrumental neutron activation was used for the determination of 23 trace and minor elements in 4 different samples of brewer's yeast. Detection limits vary from 2 ppb to 100 ppm. The following average concentrations were found (ppm, dry weight): Al 597, Br 0.36, Cl 1473, Co 0.21, Cu 19, Fe 285, K 16400, Mg 1355, Mn 8.4, Na 2330, Rb 19, Sb 0.053, Se 1.2, V 2.2 and Zn 80. NBS standard 1569 was also analyzed and the following concentrations (in ppm) were measured: Al 2300, Br 0.65, Ce 0.23, Cl 460, Co 0.26, Cr 2.12, Cu 11, Fe 707, Gd 7.1, Hf 0.13, K 15500, Mg 1780, Mn 7, Na 510, Rb 16, Sb 0.075, Sc 0.18, Se 0.92, Th 3.7, Ti 38, U 0.49, V 4.1 and Zn 70. (author)

The preparation of synthetic standards for use in instrumental neutron-activation analysis

International Nuclear Information System (INIS)

Eddy, B.T.; Watterson, J.I.W.; Erasmus, C.S.

1979-01-01

An account is given of the formulation and preparation of synthetic standards suitable for the routine analysis of minerals, ores, and ore concentrates by instrumental neutron activation. Fifteen standards were prepared, each containing from one to seven elements. The standards contain forty-four elements that produce isotopes with half-lives longer than 12 hours. An evaluation of the accuracy and precision of the method of preparation is given

Aerial Neutron Detection: Neutron Signatures for Nonproliferation and Emergency Response Applications

Energy Technology Data Exchange (ETDEWEB)

Maurer, Richard J.; Stampahar, Thomas G.; Smith, Ethan X.; Mukhopadhyay, Sanjoy; Wolff, Ronald S.; Rourke, Timothy J.; LeDonne, Jeffrey P.; Avaro, Emanuele; Butler, D. Andre; Borders, Kevin L.; Stampahar, Jezabel; Schuck, William H.; Selfridge, Thomas L.; McKissack, Thomas M.; Duncan, William W.; Hendricks, Thane J.

2012-10-17

From 2007 to the present, the Remote Sensing Laboratory has been conducting a series of studies designed to expand our fundamental understanding of aerial neutron detection with the goal of designing an enhanced sensitivity detection system for long range neutron detection. Over 35 hours of aerial measurements in a helicopter were conducted for a variety of neutron emitters such as neutron point sources, a commercial nuclear power reactor, nuclear reactor spent fuel in dry cask storage, depleted uranium hexafluoride and depleted uranium metal. The goals of the project were to increase the detection sensitivity of our instruments such that a 5.4 × 104 neutron/second source could be detected at 100 feet above ground level at a speed of 70 knots and to enhance the long-range detection sensitivity for larger neutron sources, i.e., detection ranges above 1000 feet. In order to increase the sensitivity of aerial neutron detection instruments, it is important to understand the dynamics of the neutron background as a function of altitude. For aerial neutron detection, studies have shown that the neutron background primarily originates from above the aircraft, being produced in the upper atmosphere by galactic cosmic-ray interactions with air molecules. These interactions produce energetic neutrons and charged particles that cascade to the earth’s surface, producing additional neutrons in secondary collisions. Hence, the neutron background increases as a function of altitude which is an impediment to long-range neutron detection. In order to increase the sensitivity for long range detection, it is necessary to maintain a low neutron background as a function of altitude. Initial investigations show the variation in the neutron background can be decreased with the application of a cosmic-ray shield. The results of the studies along with a representative data set are presented.

Elemental Study in Soybean and Products by Neutron Activation Analysis

International Nuclear Information System (INIS)

Vorapot, Permnamtip; Arporn Busamongkol; Sirinart, Laoharojanaphand

2009-07-01

Full text: Elements were analyzed in soybean and products by Instrumental Neutron Activation Analysis (INAA), Pseudo-Cyclic Instrumental Neutron Activation Analysis (PCINAA) and Epithermal Instrumental Neutron Activation Analysis (EINAA). Elements detected in sample were include Al, Br, Ca, Cl, Cu, Fe, I, K, Mg, Mn Na, Se and Zn. The result showed that the nutritional contents changed after food processing. From experiments (n = 2), it was found that after food processing, the concentration of Cl and Na in soy bean curd increased from 0.0045 and 0.0011% to found 0.91 and 0.39 %, respectively. Other elements did not differ from soybean. Limits of detection for Al, Br, Ca, Cl, Cu, Fe, I, K, Mg, Mn Na, Se and Zn were 0.05, 0.2, 50, 6, 10, 15, 0.05, 30, 40, 5, 5, 0.05 and 1 mg.kg - 1, respectively

Instrumental neutron activation analysis of proposed marine sediment reference material (IAEA-158)

International Nuclear Information System (INIS)

Siddique, N.; Waheed, S.

2009-01-01

IAEA-158, sediment prepared by the International Atomic Energy Agency -Marine Environmental Laboratory (IAEA-MEL), Monaco was received under the IAEA Analytical Quality Control Services (AQCS) Intercomparison Programme. Instrumental Neutron Activation Analysis (INAA) was used to determine AI, As, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, V, Vb and Zn in this proposed reference material (RM). Four different irradiation protocols were adopted using a miniature neutron source reactor (MNSR) by varying the irradiation, cooling and counting times. IAEA-405 (Estuarine Sediment) and IAEA-SLI (Lake Sediment) were used as compatible matrix reference materials for quality assurance (QA) purposes. Good agreement between our data and lAEA certified values was obtained providing confidence in the reported data. (author)

Thermal neutron self-shielding correction factors for large sample instrumental neutron activation analysis using the MCNP code

International Nuclear Information System (INIS)

Tzika, F.; Stamatelatos, I.E.

2004-01-01

Thermal neutron self-shielding within large samples was studied using the Monte Carlo neutron transport code MCNP. The code enabled a three-dimensional modeling of the actual source and geometry configuration including reactor core, graphite pile and sample. Neutron flux self-shielding correction factors derived for a set of materials of interest for large sample neutron activation analysis are presented and evaluated. Simulations were experimentally verified by measurements performed using activation foils. The results of this study can be applied in order to determine neutron self-shielding factors of unknown samples from the thermal neutron fluxes measured at the surface of the sample

Capability and limitation study of the DDT passive-active neutron waste assay instrument

International Nuclear Information System (INIS)

Nicholas, N.J.; Coop, K.L.; Estep, R.J.

1992-05-01

The differential-dieaway-technique passive-active neutron assay system is widely used by transuranic waste generators to certify their drummed waste for eventual shipment to the Waste Isolation Pilot Plant (WIPP). Stricter criteria being established for waste emplacement at the WIPP site has led to a renewed interest in improvements to and a better understanding of current nondestructive assay (NDA) techniques. Our study includes the effects of source position, extreme matrices, high neutron backgrounds, and source self-shielding to explore the system's capabilities and limitations and to establish a basis for comparison with other NDA systems. 11 refs

Determination of gold and silver in geological standard samples MGI by instrument neutron activation analysis

International Nuclear Information System (INIS)

Lu Huijiuan; Zhou; Yunlu

1987-01-01

Gold and silver in geological standard samples MGI were determined by instrument neutron activation analysis. The various interferences of nuclides were considered. Corrected factors of the geometry in different positions have been determined. Using the geological standard sample MGM and radiochemical separation neutron activation method as reference, the reliability of this method is proved. Gold content in samples is 0.4-0.009 g/t, silver content is 9-0.3 g/t. Standard deviation is less than 3.5%, the precision of the measurement is 4.8-11.6%

Polarized neutrons

International Nuclear Information System (INIS)

Williams, W.G.

1988-01-01

The book on 'polarized neutrons' is intended to inform researchers in condensed matter physics and chemistry of the diversity of scientific problems that can be investigated using polarized neutron beams. The contents include chapters on:- neutron polarizers and instrumentation, polarized neutron scattering, neutron polarization analysis experiments and precessing neutron polarization. (U.K.)

The use of instrumental neutron activation analysis for the determination of arsenic concentrations in poultry

International Nuclear Information System (INIS)

Bolton, B.A.; Hopke, Ph.K.

1975-01-01

There has been recent public concern over the use of organic arsenicals as medicaments and growth stimulators for poultry. In early studies, there was a correlation shown between the intake of arsenic and carcinogenisis. Several investigators have stronly disputed these results. The purpose of this study was not to verify or discredit this carcinogenic theory but simply to determine if the arsenic levels in poultry could be measured using instrumental activation analysis. These analyses indicate that arsenic concentrations in poultry can be measured at levels below the mandatory maximum levels of arsenic in poultry, in the investigated cases it varied between 0.3 and 0.03 ppm. Nondestructive, instrumental neutron activation analysis with a simple comparative evaluation was used: arsenic concentrations were determined by comparing the sample gamma-ray peak area to the standard peak area. (T.G.)

Neutron Research in HANARO

International Nuclear Information System (INIS)

Kim, Hark Rho

2005-01-01

HANARO (High-flux Advanced Neutron Application Reactor), which was designed and constructed by indigenous technology, is a world-class multi-purpose research reactor with a design thermal power of 30 MW, providing high neutron flux for various applications in Korea. HANARO has been operated since its first criticality in February 1995, and is now successfully utilized in such areas as neutron beam research, fuel and materials tests, radioisotopes and radiopharmaceuticals production, neutron activation analysis, and neutron transmutation doping, etc. A number of experimental facilities have been developed and installed since the beginning of reactor operation, and R and D activities for installing more facilities are actively under progress. Three flux traps in the core (CT, IR1, IR2), providing a high fast neutron flux, can be used for materials and fuel irradiation tests. They are also proper for production of high specific activity radioisotopes. Four vertical holes in the outer core region, abundant in epithermal neutrons, are used for fuel or material tests and radioisotope production. In the heavy water reflector region, 25 vertical holes with high quality thermal neutrons are located for radioisotope production, neutron activation analysis, neutron transmutation doping and cold neutron source installation. The two largest holes named NTD1 and NTD2 are for neutron transmutation doping, CNS for the cold neutron source installation, and LH for the irradiation of large targets. The high resolution powder diffractometer (HRPD) became operational in 1998, followed by the four circle diffractometer (FCD) in 1999, the residual stress instrument (RSI) in 2000, and the small angle neutron spectrometer (SANS) in 2001, respectively. HRPD and SANS became the most popular instruments these days, attracting wide range of users from academia, institutes and industries. We have made a lot of efforts during the last 10 years to develop some key components such as

Determination of toxic elements in tobacco products by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Ahmad, S.; Chaudhry, M.S.; Qureshi, I.H.

1979-01-01

The concentration of 15 elements in various brands of cigarette tobacco and cigarette wrapping paper were determined using instrumental neutron activation analysis. The paper of some of the brands contains higher concentrations of toxic elements than the tobacco. The cigarette filter and the ash were also analyzed to determine the adsorption of toxic elements on the filter and their transference in smoke. The toxic effects of some of the elements have been briefly discussed. (author)

Elemental analysis of granite by instrumental neutron activation analysis (INAA) and X-ray fluorescence analysis (XRF)

International Nuclear Information System (INIS)

El-Taher, A.

2012-01-01

The instrumental neutron activation analysis technique (INAA) was used for qualitative and quantitative analysis of granite samples collected from four locations in the Aswan area in South Egypt. The samples were prepared together with their standards and simultaneously irradiated in a neutron flux of 7×10 11 n/cm 2 s in the TRIGA Mainz research reactor. Gamma-ray spectra from an hyper-pure germanium detector were analyzed. The present study provides the basic data of elemental concentrations of granite rocks. The following elements have been determined Na, Mg, K, Fe, Mn, Sc, Cr, Ti, Co, Zn, Ga, Rb, Zr, Nb, Sn, Ba, Cs, La, Ce, Nd, Sm, Eu, Yb, Lu, Hf, Ta, Th and U. The X-ray fluorescence (XRF) was used for comparison and to detect elements, which can be detected only by XRF such as F, S, Cl, Co, Cu, Mo, Ni, Pb, Se and V. The data presented here are our contribution to understanding the elemental composition of the granite rocks. Because there are no existing databases for the elemental analysis of granite, our results are a start to establishing a database for the Egyptian granite. It is hoped that the data presented here will be useful to those dealing with geochemistry, granite chemistry and related fields. - Highlights: ► Instrumental neutron activation analysis technique (INAA) was used for qualitative and quantitative analysis of granite. ► The samples were prepared together with their standards and simultaneously irradiated in a neutron flux of 7×10 11 n/cm 2 s in the TRIGA Mainz research reactor. ► Following elements have been determined Na, Mg, K, Fe, Mn, Sc, Cr, Ti, Co, Zn, Ga, Rb, Zr, Nb, Sn, Ba, Cs, La, Ce, Nd, Sm, Eu, Yb, Lu, Hf, Ta, Th and U.

Very slow neutrons

International Nuclear Information System (INIS)

Frank, A.

1983-01-01

The history is briefly presented of the research so far of very slow neutrons and their basic properties are explained. The methods are described of obtaining very slow neutrons and the problems of their preservation are discussed. The existence of very slow neutrons makes it possible to perform experiments which may deepen the knowledge of the fundamental properties of neutrons. Their wavelength approximates that of visible radiation. The possibilities and use are discussed of neutron optical systems (neutron microscope) which could be an effective instrument for the study of the detailed arrangement, especially of organic substances. (B.S.)

A time-of-flight neutron reflectometer for surface and interfacial studies

International Nuclear Information System (INIS)

Penfold, J.; Ward, R.C.; Williams, W.G.

1987-03-01

A time-of-flight neutron reflectometer constructed for surface and interfacial studies, and installed at the ISIS pulsed neutron source, is described. One of its important design features is its inclined incident beam, since this allows both liquid and solid surface phenomena to be investigated. Measurements are presented to show the performance of the instrument, and new representative results, which include studies of liquid surfaces, Langmuir-Blodgett films, and thin film multilayers, are included as illustrations of the scientific potential of the method. (author)

The study of the trace element in organisms by neutron analysis. I. Multielement instrumental neutron activation analysis of cannabis

International Nuclear Information System (INIS)

Shinogi, M.; Murai, Y.; Mori, I.; Takeuchi, T.

1977-05-01

Examinations were made on optimal experimental conditions for instrumental determination of various elements in cannabis by neutron activation analysis, without any radiochemical separation, and the following conditions were found to be useful. Irradiation samples to be used are about 300 mg of the leaves or stem bark, and about 100 mg of the root. For soil sample, about 50 mg is used for the determination of short half-life nuclides and about 300 mg for long half-life nuclides. For short half-life nuclides, the samples are irradiated for 1 min, activity is measured for 200 sec after a decay of 3 min, and for 400 sec after a decay of 10 min. For long half-life nuclides, the samples are irradiated for 60 min and the activities are measured for 4 K sec after 1 week and for 10 K sec after 1 month. Use of supersonic waves is also convenient for cleansing of the samples. Thirty-five kinds of interesting elements were determined by this method from cannabis cultivated in Maizuru area. (Author)

Study of the trace element in organisms by neutron activation analysis, 1. Multielement instrumental neutron activation analysis of cannabis

Energy Technology Data Exchange (ETDEWEB)

Shinogi, M; Murai, Y; Mori, I [Kobe Women' s Coll. of Pharmacy (Japan); Takeuchi, T

1974-12-01

Examinations were made on optimal experimental conditions for instrumental determination of various elements in cannabis by neutron activation analysis, without any radiochemical separation, and the following conditions were found to be useful. Irradiation samples to be used are about 300 mg of the leaves or stem bark, and about 100 mg of the root. For soil sample, about 50 mg is used for the determination of short half-life nuclides and about 300 mg for long half-life nuclides. For short half-life nuclides, the samples are irradiated for 1 min, activity is measured for 200 sec after a decay of 3 min, and for 400 sec after a decay of 10 min. For long half-life nuclides, the samples are irradiated for 60 min and the activites are measured for 4 K sec after 1 week and for 10 K sec after 1 month. Use of supersonic waves is also convenient for cleansing of the samples. Thirty-five kinds of interesting elements were determined by this method from cannabis cultivated in Maizuru area.

Characterization of inorganic compounds in nutritional supplements by the instrumental neutron activation analysis

International Nuclear Information System (INIS)

Nardi, Daniela T.; Saiki, Mitiko; Vasconcellos, Maria B.A.

2000-01-01

In this work instrumental neutron activation analysis was applied in the analyses of samples of nutritional supplements in order to evaluate the composition of their essential inorganic components. Results obtained in these analyses presented, in general, a good agreement with the label values. Precision and accuracy of the results were also evaluated by analyzing NIST 2704 Buffalo River Sediment and NIST 1400 Bone Ash reference materials. (author)

Non-destructive diagnostics of irradiated materials using neutron scattering from pulsed neutron sources

Energy Technology Data Exchange (ETDEWEB)

Korenev, Sergey E-mail: sergey_korenev@steris.com; Sikolenko, Vadim

2004-10-01

The advantage of neutron-scattering studies as compared to the standard X-ray technique is the high penetration of neutrons that allow us to study volume effects. The high resolution of instrumentation on the basis neutron scattering allows measurement of the parameters of lattice structure with high precision. We suggest the use of neutron scattering from pulsed neutron sources for analysis of materials irradiated with pulsed high current electron and ion beams. The results of preliminary tests using this method for Ni foils that have been studied by neutron diffraction at the IBR-2 (Pulsed Fast Reactor at Joint Institute for Nuclear Research) are presented.

Non-destructive diagnostics of irradiated materials using neutron scattering from pulsed neutron sources

Science.gov (United States)

Korenev, Sergey; Sikolenko, Vadim

2004-09-01

The advantage of neutron-scattering studies as compared to the standard X-ray technique is the high penetration of neutrons that allow us to study volume effects. The high resolution of instrumentation on the basis neutron scattering allows measurement of the parameters of lattice structure with high precision. We suggest the use of neutron scattering from pulsed neutron sources for analysis of materials irradiated with pulsed high current electron and ion beams. The results of preliminary tests using this method for Ni foils that have been studied by neutron diffraction at the IBR-2 (Pulsed Fast Reactor at Joint Institute for Nuclear Research) are presented.

Instrumental neutron activation analysis (INAA) of some clayey rocks of Poland

International Nuclear Information System (INIS)

Janczyszyn, J.; Domanska, G.; Wyszomirski, P.

1988-01-01

The instrumental neutron activation analysis (INAA) was applied for determination of minor and trace element contents in some Polish clayey rocks. Lower Silesian kaolins from Wyszonowice near Strzelin and from Wadroze Wielkie near Legnica as well as allite from Kaplonosy (Lublin Coal Basin) were investigated. The contents of 26 elements were determined, including rare earth metals (Sc, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu), actinides (U, Th), alkali metals (Na, K, Rb, Cs) and gold. INAA studies allowed to determine the variability of minor and trace element contents in the weathering profile in 2,5/K borehole in Wyszonowice and in size fractions separated from kaolin of Wadroze Wielkie. When using this method, the effectiveness of chemical and thermal extraction of these elements from allite of Kaplonosy was checked, too. (author)

Instrumental neutron activation analysis of iron and zinc in compact cosmetic products

International Nuclear Information System (INIS)

Kanias, G.D.

1987-01-01

An instrumental neutron activation analysis method is described for the determination of iron and zinc in compact eye shadow, compact face powder and compact rouge make-up cosmetic products. The steps of the procedure are: Irradiation of samples with thermal neutrons, counting of gamma-radioactivity of the radioisotopes of iron and zinc produced by this irradiation and calculation of the concentration of these elements from the gamma-ray spectra of samples and standards. Analysis of the I.A.E.A. standard reference material by this procedure give results in close agreement with certified values. The limit of quantitation is 45 μg for iron and 0.35 μg for zinc. The developed procedure could possibly be established as an official method for the simultaneous determination of iron and zinc in compact cosmetic products. (orig.) [de

Development of new methods for studying nanostructures using neutron scattering

Energy Technology Data Exchange (ETDEWEB)

Pynn, Roger [Indiana Univ., Bloomington, IN (United States)

2016-03-18

The goal of this project was to develop improved instrumentation for studying the microscopic structures of materials using neutron scattering. Neutron scattering has a number of advantages for studying material structure but suffers from the well-known disadvantage that neutrons’ ability to resolve structural details is usually limited by the strength of available neutron sources. We aimed to overcome this disadvantage using a new experimental technique, called Spin Echo Scattering Angle Encoding (SESAME) that makes use of the neutron’s magnetism. Our goal was to show that this innovation will allow the country to make better use of the significant investment it has recently made in a new neutron source at Oak Ridge National Laboratory (ORNL) and will lead to increases in scientific knowledge that contribute to the Nation’s technological infrastructure and ability to develop advanced materials and technologies. We were successful in demonstrating the technical effectiveness of the new method and established a baseline of knowledge that has allowed ORNL to start a project to implement the method on one of its neutron beam lines.

Recent development of the Multi-Grid detector for large area neutron scattering instruments

International Nuclear Information System (INIS)

Guerard, Bruno

2015-01-01

Most of the Neutron Scattering facilities are committed in a continuous program of modernization of their instruments, requiring large area and high performance thermal neutron detectors. Beside scintillators detectors, 3 He detectors, like linear PSDs (Position Sensitive Detectors) and MWPCs (Multi-Wires Proportional Chambers), are the most current techniques nowadays. Time Of Flight instruments are using 3 He PSDs mounted side by side to cover tens of m 2 . As a result of the so-called ' 3 He shortage crisis , the volume of 3He which is needed to build one of these instruments is not accessible anymore. The development of alternative techniques requiring no 3He, has been given high priority to secure the future of neutron scattering instrumentation. This is particularly important in the context where the future ESS (European Spallation Source) will start its operation in 2019-2020. Improved scintillators represent one of the alternative techniques. Another one is the Multi-Grid introduced at the ILL in 2009. A Multi-Grid detector is composed of several independent modules of typically 0.8 m x 3 m sensitive area, mounted side by side in air or in a vacuum TOF chamber. One module is composed of segmented boron-lined proportional counters mounted in a gas vessel; the counters, of square section, are assembled with Aluminium grids electrically insulated and stacked together. This design provides two advantages: First, magnetron sputtering techniques can be used to coat B 4 C films on planar substrates, and second, the neutron position along the anode wires can be measured by reading out individually the grid signals with fast shaping amplifiers followed by comparators. Unlike charge division localisation in linear PSDs, the individual readout of the grids allows operating the Multi-Grid at a low amplification gain, hence this detector is tolerant to mechanical defects and its production accessible to laboratories equipped with standard equipment. Prototypes of

Recent development of the Multi-Grid detector for large area neutron scattering instruments

Energy Technology Data Exchange (ETDEWEB)

Guerard, Bruno [ILL-ESS-LiU collaboration, CRISP project, Institut Laue Langevin - ILL, Grenoble (France)

2015-07-01

Most of the Neutron Scattering facilities are committed in a continuous program of modernization of their instruments, requiring large area and high performance thermal neutron detectors. Beside scintillators detectors, {sup 3}He detectors, like linear PSDs (Position Sensitive Detectors) and MWPCs (Multi-Wires Proportional Chambers), are the most current techniques nowadays. Time Of Flight instruments are using {sup 3}He PSDs mounted side by side to cover tens of m{sup 2}. As a result of the so-called '{sup 3}He shortage crisis{sup ,} the volume of 3He which is needed to build one of these instruments is not accessible anymore. The development of alternative techniques requiring no 3He, has been given high priority to secure the future of neutron scattering instrumentation. This is particularly important in the context where the future ESS (European Spallation Source) will start its operation in 2019-2020. Improved scintillators represent one of the alternative techniques. Another one is the Multi-Grid introduced at the ILL in 2009. A Multi-Grid detector is composed of several independent modules of typically 0.8 m x 3 m sensitive area, mounted side by side in air or in a vacuum TOF chamber. One module is composed of segmented boron-lined proportional counters mounted in a gas vessel; the counters, of square section, are assembled with Aluminium grids electrically insulated and stacked together. This design provides two advantages: First, magnetron sputtering techniques can be used to coat B{sub 4}C films on planar substrates, and second, the neutron position along the anode wires can be measured by reading out individually the grid signals with fast shaping amplifiers followed by comparators. Unlike charge division localisation in linear PSDs, the individual readout of the grids allows operating the Multi-Grid at a low amplification gain, hence this detector is tolerant to mechanical defects and its production accessible to laboratories equipped with standard

Instrumental neutron activation analysis for the certification of biological reference materials

International Nuclear Information System (INIS)

Ambulkar, M.N.; Chutke, N.L.; Garg, A.N.

1992-01-01

A multielemental instrumental neutron activation analysis (INAA) method by short and long irradiation has been employed for the determination of 22 minor and trace constituents in two proposed Standard Reference Materials P-RBF and P-WBF from Institute of Radioecology and Applied Nuclear Techniques, Czechoslovakia. Also some biological standards such as Bowen's Kale, Cabbage leaves (Poland) including wheat and rice flour samples of local origin were analysed. It is suggested that INAA is an ideal method for the certification of reference materials of biological matrices. (author). 7 refs., 1 tab

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

International Nuclear Information System (INIS)

Boniforti, R.; Moauro, A.; Madaro, M.

1983-01-01

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

Neutron scattering. Annual progress report 1997

International Nuclear Information System (INIS)

Allenspach, P.; Boeni, B.; Fischer, P.; Furrer, A.

1998-02-01

The present progress report describes the scientific and technical activities obtained by LNS staff members in 1997. It also includes the work performed by external groups at our CRG instruments D1A and IN3 at the ILL Grenoble. Due to the outstanding properties of neutrons and x-rays the research work covered many areas of science and materials research. The highlight of the year 1997 was certainly the production of neutrons at the new spallation neutron source SINQ. From July to November, SINQ was operating for typically two days/week and allowed the commissioning of four instruments at the neutron guide system: - the triple-axis spectrometer Druechal, - the powder diffractometer DMC, - the double-axis diffractometer TOPSI, the polarised triple-axis spectrometer TASP. These instruments are now fully operational and have already been used for condensed matter studies, partly in cooperation with external groups. Five further instruments are in an advanced state, and their commissioning is expected to occur between June and October 1998: - the high-resolution powder diffractometer HRPT, - the single-crystal diffractometer TriCS, - the time-of-flight spectrometer FOCUS, - the reflectometer AMOR, - the neutron optical bench NOB. Together with the small angle neutron scattering facility SANS operated by the spallation source department, all these instruments will be made available to external user groups in the future. (author) figs., tabs., refs

Systematic study on the performance of elliptic focusing neutron guides

International Nuclear Information System (INIS)

Martin Rodriguez, D.; DiJulio, D.D.; Bentley, P.M.

2016-01-01

In neutron scattering experiments there is an increasing trend towards the study of smaller volume samples, which make the use of focusing optics more important. Focusing guide geometries based on conic-sections, such as those with parabolic and elliptic shapes, have been extensively used in both recently built neutron instruments and upgrades of existing hardware. A large fraction of proposed instruments at the European Spallation Source feature the requirement of good performance when measuring on small samples. The optimised design of a focusing system comes after time consuming Monte-Carlo (MC) simulations. Therefore, in order to help reduce the time needed to design such focusing systems, it is necessary to study systematically the performance of focusing guides. In the present work, we perform a theoretical analysis of the focusing properties of neutron beams, and validate them using a combination of Monte-Carlo simulations and Particle Swarm Optimisations (PSOs), where there is a close correspondence between the maximum divergence of the beam and the shape of the guide. The analytical results show that two limits can be considered, which bound a range of conic section shapes that provide optimum performance. Finally, we analyse a more realistic guide example and we give an assessment of the importance of the contribution from multiple reflections in different systems.

Determination of phosphorus in wheat grass samples by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Kulkarni, S.D.; Rajurkar, N.S.; Acharya, R.; Nair, A.G.C.; Reddy, A.V.R.

2005-01-01

An instrumental neutron activation analysis (INAA) method using β-counting was used to determine phosphorus in wheat grass; grown in three different conditions. The phosphorus concentration was found to be in the range of 950-23000 mg/g in the samples grown in different conditions. The accuracy of the method was evaluated by determining phosphorus in three reference materials and the % deviations were within 10%. Reliability of the method was checked by following the half-life of the 32 P. (author)

Neutron scattering at the high-flux isotope reactor

International Nuclear Information System (INIS)

Cable, J.W. Chakoumakos, B.C.; Dai, P.

1995-01-01

The title facilities offer the brightest source of neutrons in the national user program. Neutron scattering experiments probe the structure and dynamics of materials in unique and complementary ways as compared to x-ray scattering methods and provide fundamental data on materials of interest to solid state physicists, chemists, biologists, polymer scientists, colloid scientists, mineralogists, and metallurgists. Instrumentation at the High- Flux Isotope Reactor includes triple-axis spectrometers for inelastic scattering experiments, a single-crystal four diffractometer for crystal structural studies, a high-resolution powder diffractometer for nuclear and magnetic structure studies, a wide-angle diffractometer for dynamic powder studies and measurements of diffuse scattering in crystals, a small-angle neutron scattering (SANS) instrument used primarily to study structure-function relationships in polymers and biological macromolecules, a neutron reflectometer for studies of surface and thin-film structures, and residual stress instrumentation for determining macro- and micro-stresses in structural metals and ceramics. Research highlights of these areas will illustrate the current state of neutron science to study the physical properties of materials

Determination of trace elements in the seeds of fruits using instrumental neutron activation analysis (INAA) in Arak, I.R. Iran

International Nuclear Information System (INIS)

Pourimani Reza; Meighani Elham; Fathivand Aliasghar

2018-01-01

In this study, four fruit's seed samples as Punica granatum L., Citrus medica var. limonum, Malus domestica L. and Citrus vulgaris Risso were prepared from Arak's markets. They were analyzed using instrumental neutron activation method (INAA). In this method, Tehran research reactor as a neutron source and relative INAA method has been used as the analysis method and to record gamma ray spectrum, the high purity germanium detector was used. Pomegranate seeds had the highest number of essential elements. Apple seeds and sour orange seeds contain the highest levels of Mg and K, Respectively. (author)

Studies of generalized elemental imbalances in neurological disease patients using INAA [instrumental neutron activation analysis

International Nuclear Information System (INIS)

Ehmann, W.D.; Vance, D.E.; Khare, S.S.; Kasarskis, E.J.; Markesbery, W.R.

1988-01-01

Evidence has been presented in the literature to implicate trace elements in the etiology of several age-related neurological diseases. Most of these studies are based on brain analyses. Using instrumental neutron activation analysis (INAA), we have observed trace element imbalances in brains of patients with Alzheimer's disease, amyotrophic lateral sclerosis (ALS), and Picks's disease. The most prevalent elemental imbalances found in the brain were for bromine, mercury, and the alkali metals. In this study the authors report INAA studies of trace elements in nonneural tissues from Alzheimer's disease and ALS patients. Samples from household relatives were collected for use as controls wherever possible. Hair samples were washed according to the International Atomic Energy Agency recommended procedure. Fingernail samples were scraped with a quartz knife prior to washing by the same procedure. For ALS patients, blood samples were also collected. These data indicate that elemental imbalances in Alzheimer's disease and ALS are not restricted to the brain. Many elements perturbed in the brain are also altered in the several nonneural tissues examined to date. The imbalances in different tissues, however, are not always in the same direction. The changes observed may represent causes, effects, or simply epiphenomena. Longitudinal studies of nonneural tissues and blood, as well as tissue microprobe analyses at the cellular and subcellular level, will be required in order to better assess the role of trace elements in the etiology of these diseases

Instrumental Neutron Activation Analysis in archaeology interpretation beyond elemental abundance

International Nuclear Information System (INIS)

Bishop, Ronald L.

2001-01-01

Application of instrumental neutron activation analysis to the study of archaeological ceramics involves the determination of the source or sources used to produce pottery. Groups of relatively homogeneous elemental abundances are shown to be statically distinct from one another often leading to the assesment of what was locally produced and what was imported to a site. These assesment, however are among the most preliminary interpretations. Archaeology is concerned with the reasons for artificial distributions and how and why the distribution varied through time 3 reasons that include the social and political basis of ancient economics and how these responded to other factors, such as ideology. These objectives are addressed through the increasing refinement of compositional groups leading toward greater specificity of attribution. In so doing the role of analytical precision among other considerations groves in importance. This paper illustration some of these considerations with examples from the U.S. southwest, the Maya region of southern mexico, and lower central America

Instrumental neutron activation analysis of prehistoric and ancient bone remains

International Nuclear Information System (INIS)

Vasidov, A.; Osinskaya, N.S.; Khatamov, Sh.; Rakhmanova, T.

2008-01-01

Instrumental neutron activation analysis (INAA) was used to study the element contents in bones of prehistoric dinosaurs and bones of an ancient bear and an archantrop (ancient person), which were found on the territory of Uzbekistan. Concentrations of more than 25 elements were in the range of 0.043-3600 mg/kg. Multielement analyses of bone and soil samples were carried out by INAA using the WWR-SM research nuclear reactor. Results of measurements have shown that in the dinosaurs bones the concentration of the rare earth elements (REEs) were within 280-3200 mg/kg; the uranium content reached a very high value, up to 180 mg/kg, while in soils coating the dinosaurs bones this content was 4.2 mg/kg; in the bones of the archantrop it was 1.53 mg/kg and in the bones of a standard person its amount is less than 0.016 mg/kg. (author)

Simulation of a suite of generic long-pulse neutron instruments to optimize the time structure of the European Spallation Source.

Science.gov (United States)

Lefmann, Kim; Klenø, Kaspar H; Birk, Jonas Okkels; Hansen, Britt R; Holm, Sonja L; Knudsen, Erik; Lieutenant, Klaus; von Moos, Lars; Sales, Morten; Willendrup, Peter K; Andersen, Ken H

2013-05-01

We here describe the result of simulations of 15 generic neutron instruments for the long-pulsed European Spallation Source. All instruments have been simulated for 20 different settings of the source time structure, corresponding to pulse lengths between 1 ms and 2 ms; and repetition frequencies between 10 Hz and 25 Hz. The relative change in performance with time structure is given for each instrument, and an unweighted average is calculated. The performance of the instrument suite is proportional to (a) the peak flux and (b) the duty cycle to a power of approximately 0.3. This information is an important input to determining the best accelerator parameters. In addition, we find that in our simple guide systems, most neutrons reaching the sample originate from the central 3-5 cm of the moderator. This result can be used as an input in later optimization of the moderator design. We discuss the relevance and validity of defining a single figure-of-merit for a full facility and compare with evaluations of the individual instrument classes.

Simulation of a suite of generic long-pulse neutron instruments to optimize the time structure of the European Spallation Source

Energy Technology Data Exchange (ETDEWEB)

Lefmann, Kim; Kleno, Kaspar H.; Holm, Sonja L.; Sales, Morten [Nanoscience and eScience Centers, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen O (Denmark); Danish Workpackage for the ESS Design Update Phase, Universitetsparken 5, 2100 Copenhagen O (Denmark); Birk, Jonas Okkels [Nanoscience and eScience Centers, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen O (Denmark); Danish Workpackage for the ESS Design Update Phase, Universitetsparken 5, 2100 Copenhagen O (Denmark); Laboratory for Quantum Magnetism, Ecole Polytecnique Federale de Lausanne (EPFL), 1015 Lausanne (Switzerland); Hansen, Britt R.; Knudsen, Erik; Willendrup, Peter K. [Institute of Physics, Technical University of Denmark, 2800 Lyngby (Denmark); Danish Workpackage for the ESS Design Update Phase, 2800 Lyngby (Denmark); Lieutenant, Klaus [Institute for Energy Technology, Instituttveien 18, 2007 Kjeller (Norway); Helmholtz Center for Energy and Materials, Hahn-Meitner Platz, 14109 Berlin (Germany); German Work Package for the ESS Design Update, Hahn-Meitner Platz, 14109 Berlin (Germany); Moos, Lars von [Department of Energy Conversion and Storage, Technical University of Denmark, 4000 Roskilde (Denmark); Danish Workpackage for the ESS Design Update Phase, 2800 Lyngby (Denmark); Institute for Energy Conversion, Technical University of Denmark, 4000 Roskilde (Denmark); Andersen, Ken H. [European Spallation Source ESS AB, 22100 Lund (Sweden)

2013-05-15

We here describe the result of simulations of 15 generic neutron instruments for the long-pulsed European Spallation Source. All instruments have been simulated for 20 different settings of the source time structure, corresponding to pulse lengths between 1 ms and 2 ms; and repetition frequencies between 10 Hz and 25 Hz. The relative change in performance with time structure is given for each instrument, and an unweighted average is calculated. The performance of the instrument suite is proportional to (a) the peak flux and (b) the duty cycle to a power of approximately 0.3. This information is an important input to determining the best accelerator parameters. In addition, we find that in our simple guide systems, most neutrons reaching the sample originate from the central 3-5 cm of the moderator. This result can be used as an input in later optimization of the moderator design. We discuss the relevance and validity of defining a single figure-of-merit for a full facility and compare with evaluations of the individual instrument classes.

Simulation of a suite of generic long-pulse neutron instruments to optimize the time structure of the European Spallation Source

International Nuclear Information System (INIS)

Lefmann, Kim; Klenø, Kaspar H.; Holm, Sonja L.; Sales, Morten; Birk, Jonas Okkels; Hansen, Britt R.; Knudsen, Erik; Willendrup, Peter K.; Lieutenant, Klaus; Moos, Lars von; Andersen, Ken H.

2013-01-01

We here describe the result of simulations of 15 generic neutron instruments for the long-pulsed European Spallation Source. All instruments have been simulated for 20 different settings of the source time structure, corresponding to pulse lengths between 1 ms and 2 ms; and repetition frequencies between 10 Hz and 25 Hz. The relative change in performance with time structure is given for each instrument, and an unweighted average is calculated. The performance of the instrument suite is proportional to (a) the peak flux and (b) the duty cycle to a power of approximately 0.3. This information is an important input to determining the best accelerator parameters. In addition, we find that in our simple guide systems, most neutrons reaching the sample originate from the central 3–5 cm of the moderator. This result can be used as an input in later optimization of the moderator design. We discuss the relevance and validity of defining a single figure-of-merit for a full facility and compare with evaluations of the individual instrument classes.

Requirements of data acquisition and analysis for condensed matter studies at the weapons neutron research/proton storage ring facility

International Nuclear Information System (INIS)

Johnson, M.W.; Goldstone, J.A.; Taylor, A.D.

1982-11-01

With the completion of the proton storage ring (PSR) in 1985, the subsquent increase in neutron flux, and the continuing improvement in neutron scattering instruments, a significant improvement in data acquisition and data analysis capabilities will be required. A brief account of the neutron source is given together with the associated neutron scattering instruments. Based on current technology and operating instruments, a projection for 1985 to 1990 of the neutron scattering instruments and their main parameters are given. From the expected data rates and the projected instruments, the size of data storage is estimated and the user requirements are developed. General requirements are outlined with specific requirements in user hardware and software stated. A project time scale to complete the data acquisition and analysis system by 1985 is given

Obtaining the neutron time-of-flight instrument response function for a single D-T neutron utilizing n-alpha coincidence from the d(t, α) n nuclear reaction

Science.gov (United States)

Styron, Jedediah; Ruiz, Carlos; Hahn, Kelly; Cooper, Gary; Chandler, Gordon; Jones, Brent; McWatters, Bruce; Smith, Jenny; Vaughan, Jeremy

2017-10-01

A measured neutron time-of-flight (nTOF) signal is a convolution of the neutron reaction history and the instrument response function (IRF). For this work, the IRF was obtained by measuring single, D-T neutron events by utilizing n-alpha coincidence. The d(t, α) n nuclear reaction was produced at Sandia National Laboratories' Ion Beam Laboratory using a 300-keV Cockroft-Walton generator to accelerate a 2- μA beam, of 175-keV D + ions, into a stationary, 2.6- μm, ErT2 target. Comparison of these results to those obtained using cosmic-rays and photons will be discussed. Sandia National Laboratories.

Neutrons and art

International Nuclear Information System (INIS)

Panczyk, E.; Walis, L.

2004-01-01

Following modern trends in art objects connoisseurship, through examination of the structure of art objects supports traditional studies conducted by art historians based on composition, iconographic and stylistic comparisons. It must be emphasized that complete technological examinations are carried out by means of comprehensive physical and chemical studies. Among various methods used for the examination of art objects, methods which apply neutrons such as instrumental neutron activation analysis (INAA), prompt gamma activation analysis (PGAA) and neutron-induced autoradiography are crucial due to their high sensitivity, reproducibility and capability of simultaneous determination of several tens of elements. Systematic studies on art objects using instrumental neutron activation analysis and neutron autoradiography have been carried out in the institute of Nuclear Chemistry and Technology. It was possible to accumulate a number of essential data on the concentration of trace elements particularly in chalk grounds and pigments (such as lead white, lead-tin yellow, smalt), Chinese porcelain, Thai ceramics, silver denarius, jewellery made of copper alloys, as well as in the clay fillings of Egyptian mummies. The above mentioned examination of art objects prior to their conservation helps to determine precisely the materials used in the process of creating art objects, as well as to identify the appropriate place of origin of particular materials. (author)

Instrumental neutron-activation determination of impurities in lead and titanium compounds

Energy Technology Data Exchange (ETDEWEB)

Popova, I L

1980-01-01

Instrumental neutron-activation analysis was used to determine 22 impurities in lead and titanium compounds (e.g. PbO, Pb/NO3/2, and TiO2) used as raw materials for ferroelectrics. Five elements (Al, V, Mn, Sc, and Se) were determined by short-lived isotopes and 17 elements were determined by long-lived isotopes. The detection limits were 7 x 10 to the -3rd to 2 x 10 to the -8th %. A substantial difference in concentrations of certain impurity elements has been found in different series of lead and titanium oxides of similar purity.

Evaluation and Monte Carlo modelling of the response function of the Leake neutron area survey instrument

International Nuclear Information System (INIS)

Tagziria, H.; Tanner, R.J.; Bartlett, D.T.; Thomas, D.J.

2004-01-01

All available measured data for the response characteristics of the Leake counter have been gathered together. These data, augmented by previously unpublished work, have been compared to Monte Carlo simulations of the instrument's response characteristics in the energy range from thermal to 20 MeV. A response function has been derived, which is recommended as the best currently available for the instrument. Folding this function with workplace energy distributions has enabled an assessment of the impact of this new response function to be made. Similar work, which will be published separately, has been carried out for the NM2 and the Studsvik 2202D neutron area survey instruments

Cosmetics chemical composition characterization by instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Alves, Ana Paula; Pereira, Gustavo Jose; Amaral, Angela Maria; Ferreira, Andrea Vidal, E-mail: ana_allves2008@hotmail.co [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2009-07-01

Brazil is in the third position in the world's cosmetics market. It is an expanding and growing market where new products and manufacturing processes are in a constant and steady expansion. Therefore, it is mandatory that the composition of the products is well known in order to guarantee safety and quality of daily used cosmetics. The Brazilian National Health Surveillance Agency (ANVISA) has issued a resolution, RDC No. 48, March 16, 2006, which defines a 'List of Substances which can not be used in personal hygiene products, cosmetics and perfumes'. In this work, samples of locally manufactured and imported cosmetics (lipsticks, eye shadows, etc.) were analyzed using the Instrumental Neutron Activation Analysis technique. The samples were irradiated in the TRIGA IPR-R1 reactor of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), on a 100kW thermal power, with a thermal neutron fluence rate about 8x10{sup 11}ncm{sup -2}s{sup -1}. The analysis has detected the chemical elements Br, Ba, Ga, Na, K, Sc, Fe, Cr, Zn, Sm, W, La, Rb, Cs, Ta, Ge, Co, U, Ti, V, Cl, Al, Mn and Cu. The concentrations of these elements are on a range from 5 to 3000mug.g{sup -1}. Some chemical elements observed in samples (Cl, Br, Cr, U) are included at ANVISA prohibitive list. (author)

Cosmetics chemical composition characterization by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Alves, Ana Paula; Pereira, Gustavo Jose; Amaral, Angela Maria; Ferreira, Andrea Vidal

2009-01-01

Brazil is in the third position in the world's cosmetics market. It is an expanding and growing market where new products and manufacturing processes are in a constant and steady expansion. Therefore, it is mandatory that the composition of the products is well known in order to guarantee safety and quality of daily used cosmetics. The Brazilian National Health Surveillance Agency (ANVISA) has issued a resolution, RDC No. 48, March 16, 2006, which defines a 'List of Substances which can not be used in personal hygiene products, cosmetics and perfumes'. In this work, samples of locally manufactured and imported cosmetics (lipsticks, eye shadows, etc.) were analyzed using the Instrumental Neutron Activation Analysis technique. The samples were irradiated in the TRIGA IPR-R1 reactor of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), on a 100kW thermal power, with a thermal neutron fluence rate about 8x10 11 ncm -2 s -1 . The analysis has detected the chemical elements Br, Ba, Ga, Na, K, Sc, Fe, Cr, Zn, Sm, W, La, Rb, Cs, Ta, Ge, Co, U, Ti, V, Cl, Al, Mn and Cu. The concentrations of these elements are on a range from 5 to 3000μg.g -1 . Some chemical elements observed in samples (Cl, Br, Cr, U) are included at ANVISA prohibitive list. (author)

Determination of catalyst residues in hydrocarbon fuels by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Burgess, D.D.

1982-01-01

A procedure has been developed for the determination of entrained catalytic cracking catalyst in hydrocarbon fuels. Aluminium is measured by instrumental neutron activation analysis and the amount of catalyst present is calculated from the amount of aluminium found and the known composition of the catalyst. Entrained catalyst may be determined at levels above 3 ppm with a precision of +-2%-25% according to sample composition. Only simple procedures are required. Vanadium may reduce sensitivity by dead time and pulse pile-up. No other interferences were observed. (author)

Possibilities of instrumental neutron activation and X-ray fluorescence analyses of sedimentary-magmatic metamorphosed rocks from deep borehole drill cores

International Nuclear Information System (INIS)

Gurevich, A.L.; Drynkin, V.I.; Lejpunskaya, D.I.

1977-01-01

The possibilities for instrumental neutron-activation and X-ray fluorescence analyses of rocks of metamorphized sedimentary magmatic complexes have been studied with the aid of deep-hole core. The principal characteristics of the conditions of irradiation and of sample measurement ensuring the determination of the content of 26 elements are presented. The use of X-ray fluorescence analysis enables one to determine additionally the content of stron-tium and niobium. Standard specimens of the composition of rocks and complex reference compounds based on phenol formaldehyde resins are used as metrolo.o.ical auxiliaries in the calibration system and in evaluating the correctness of the techniques of instrumental neutron activation and fluorescence analysis. The ranges of the contents to be determined, the sensitivity and relative standard deviation are given. The contribution from the nonuniformity of the specimens to the summary error of element determination is estimated. It is shown that the accuracy and error of analyses are within the allowable range

Geochemistry of single diamond crystals by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Damarupurshad, A.

1995-02-01

Neutron activation analysis is probably the most powerful technique, available to date, for the analysis of the trace elements in diamond. In this study the technique of neutron activation analysis has been modified and optimized for the analysis of single, small (0.01-0.5 carat), inclusion-bearing and inclusion-free diamonds. Instrumental neutron activation analysis was used to analyze for up to 40 different elements at the ppb and ppt levels in diamonds from Brazil, South Africa, Colorado and China. The data obtained was used to detect and understand the differences between diamonds from the eclogitic and peridotitic para geneses and between diamonds from the different localities. In this regard, two inter element ratios, i.e. Cr/Sc and Au/Ir ratios were found to be useful. It seems that diamonds from a particular locality or mine have a unique range of Cr/Sc ratios. Furthermore, the identity of the dominant silicate inclusion(s) can be deduced from the Cr/Sc ratio of the diamond, since each type of silicate inclusion has a different range of Cr/Sc ratios. Not only is the Cr/Sc ratio distinctive for silicate inclusions in diamonds, it is also distinctive for minerals co genetic with diamond, such as orange garnet, red garnet, chrome diopside and ortho pyroxene (macrocrysts) which were separated from kimberlites. Sulphide inclusions may also contain detectable quantities of Au and Ir and the ratios of these two elements can also be used to differentiate between diamonds of the two para geneses. Carbon isotope ratios of these eclogitic and peridotitic diamonds were also measured. The comparison of this with the Cr/Sc ratios revealed that the carbon isotope ratios of both para geneses overlap in a narrow range and do not show the clear separations seen with Cr/Sc and Au/Ir ratios. It can be suggested, therefore, on the basis of the suite of 61 diamonds analyzed in this study, that the Cr/Sc and Au/Ir ratios are much more useful tools to distinguish between diamonds

Determination of trace elements in airborne particulates by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Jung, Yong Sam; Jung, Yung Joo; Jung, Eui Sik; Cho, Seung Yun

1995-01-01

Trace elements in airborne particulates were analyzed by instrumental neutron activation analysis(INAA) under the optimum analytical condition. Neutron irradiation for sample was done at the irradiation hole(neutron flux, 1 x 10 13 n/cm 2 s) of TRIGA MARK-III research reactor in the Korea Atomic Energy Research Institute. For the verification of the analytical method, NIST SRM-1648 and NIES CRM No.8 were chosen and analyzed. The accuracy and precision of the analysis of 40 and 24 trace elements in the samples were compared with the certified and reported values, respectively. The analytical method was found to be reliable enough when the analytical data of NIES sample were compared with those of different countries. In the analytical result of two or both of standard reference materials, relative standard deviation was within the 15% except a few elements and the relative error was within the 10%. We used this method to analyze 30 trace elements in airborne particulates collected with the high volume air sampler(PM-10) at two different locations and also confirmed the possibility to use this method as a routine monitoring tool to find out environmental pollution sources. 3 figs., 8 tabs., 19 refs. (Author)

Experimental installations and instruments at the FRM-II

International Nuclear Information System (INIS)

Steichele, E.

1999-01-01

The new research reactor FRM-II of the Technical University Munich will be the strongest neutron source in Germany when going into operation in 2001/2002. From the beginnings on it was designed as a multipurpose research reactor based on local traditions, recent experience and new ideas. The reactor will be used for neutron scattering and material science, for fundamental physics with cold and ultracold neutrons, for isotope production, fission fragment acceleration, medical tumor treatment and for a manifold of technical and practical applications like computer tomography with fast and cold neutrons. According to the wide spectrum of applications the reactor needs a manifold of special installations and instruments, which will be introduced in the present paper. The reactor will be equipped with a liquid-D 2 cold source for high resolution neutron scattering and a solid-D 2 UCN source for fundamental physics, with a graphite hot source for high-Q neutron diffraction and a 'converter', which is a U-235 target in the thermal flux maximum to produce fast fission neutrons for medical applications and technical tomography. A series of irradiation plants is designed for production and study of radio-isotopes with half-lives as short as seconds and for phosphor-doping of semiconductor silicon crystals with diameters up to 8 inch. The reactor will be equipped with ten horizontal, one vertical and two inclined beam-tubes, one of the latter ones will take up a most intense, newly developed positron source for solid state physics. Three horizontal beam tubes will look onto the cold source, one of which will take up six neutron guides going into a neutron guide hall 50 x 25 m 2 . Most of the neutron guides will be coated with super-mirror which allows to build effective beam switches for many end-position experiments. The first generation of about 20 instruments and experimental installations as recommended by the instruments committee will be financed by the Federal and

SUSANS With Polarized Neutrons.

Science.gov (United States)

Wagh, Apoorva G; Rakhecha, Veer Chand; Strobl, Makus; Treimer, Wolfgang

2005-01-01

Super Ultra-Small Angle Neutron Scattering (SUSANS) studies over wave vector transfers of 10(-4) nm(-1) to 10(-3) nm(-1) afford information on micrometer-size agglomerates in samples. Using a right-angled magnetic air prism, we have achieved a separation of ≈10 arcsec between ≈2 arcsec wide up- and down-spin peaks of 0.54 nm neutrons. The SUSANS instrument has thus been equipped with the polarized neutron option. The samples are placed in a uniform vertical field of 8.8 × 10(4) A/m (1.1 kOe). Several magnetic alloy ribbon samples broaden the up-spin neutron peak significantly over the ±1.3 × 10(-3) nm(-1) range, while leaving the down-spin peak essentially unaltered. Fourier transforms of these SUSANS spectra corrected for the instrument resolution, yield micrometer-range pair distribution functions for up- and down-spin neutrons as well as the nuclear and magnetic scattering length density distributions in the samples.

Upgrade of the neutron guide system at the OPAL Neutron Source

International Nuclear Information System (INIS)

Rodriguez, D Martin; Kennedy, S J; Klose, F

2010-01-01

The new research reactor at ANSTO (OPAL) is operating with seven neutron beam instruments in the user programme and three more under construction. The reactor design provides for expansion of the facility to eighteen instruments, and much of the basic infrastructure is already in place. However, an expansion of the neutron guide system is needed for further beam instruments. For this purpose, several possibilities are under consideration, such as insertion of multi-channel neutron benders in the existing cold guides or the construction of a new elliptic cold guide. In this work Monte Carlo (MC) simulations have been used to evaluate performance of these guide configurations. Results show that these configurations can be competitive with the best instruments in the world.

Electron volt neutron spectrometers

International Nuclear Information System (INIS)

Pietropaolo, A.; Senesi, R.

2011-01-01

The advent of pulsed neutron sources has made available intense fluxes of epithermal neutrons (500 meV ≤E≤100 eV ). The possibility to open new investigations on condensed matter with eV neutron scattering techniques, is related to the development of methods, concepts and devices that drive, or are inspired by, emerging studies at this energy scale. Electron volt spectrometers have undergone continuous improvements since the construction of the first prototype instruments, but in the last decade major breakthroughs have been accomplished in terms of resolution and counting statistics, leading, for example, to the direct measurement of the proton 3-D Born–Oppenheimer potential in any material, or to quantitatively probe nuclear quantum effects in hydrogen bonded systems. This paper reports on the most effective methods and concepts for energy analysis and detection, as well as devices for the optimization of electron volt spectrometers for different applications. This is set in the context of the progress made up to date in instrument development. Starting from early stages of development of the technique, particular emphasis will be given to the Vesuvio eV spectrometer at the ISIS neutron source, the first spectrometer where extensive scientific, as well as research and development programmes have been carried out. The potential offered by this type of instrumentation, from single particle excitations to momentum distribution studies, is then put in perspective into the emerging fields of eV spectroscopy applied to cultural heritages and neutron irradiation effects in electronics. - Highlights: ► Neutron spectrometers at eV energies. ► Methods and techniques for eV neutrons counting at spallation sources. ► Scattering, imaging and radiation hardness tests with multi-eV neutrons.

The neutron silicon lens. An update of the thermal neutron lens results

International Nuclear Information System (INIS)

Johnson, M.W.; Daymond, M.R.

2001-01-01

This paper introduces the concept of the Neutron Silicon Lens (NSL) and provides and update on the experimental results achieved to date. The NSL design is a cylindrical neutron lens based on the use of multiple neutron mirrors supported and separated by silicon wafers. Such lenses would have many applications in both the primary and scattered beams on neutron instruments, and would lead to immediate improvements where the sample to be illuminated is small, as in high pressure or engineering strain scanning instruments. (author)

The neutron silicon lens. An update of the thermal neutron lens results

Energy Technology Data Exchange (ETDEWEB)

Johnson, M.W.; Daymond, M.R. [Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire (United Kingdom)

2001-03-01

This paper introduces the concept of the Neutron Silicon Lens (NSL) and provides and update on the experimental results achieved to date. The NSL design is a cylindrical neutron lens based on the use of multiple neutron mirrors supported and separated by silicon wafers. Such lenses would have many applications in both the primary and scattered beams on neutron instruments, and would lead to immediate improvements where the sample to be illuminated is small, as in high pressure or engineering strain scanning instruments. (author)

Neutron powder diffraction at a pulsed neutron source: a study of resolution effects

International Nuclear Information System (INIS)

Faber, J. Jr.; Hitterman, R.L.

1985-11-01

The General Purpose Powder Diffractometer (GPPD), a high resolution (Δd/d = 0.002) time-of-flight instrument, exhibits a resolution function that is almost independent of d-spacing. Some of the special properties of time-of-flight scattering data obtained at a pulsed neutron source will be discussed. A method is described that transforms wavelength dependent data, obtained at a pulsed neutron source, so that standard structural least-squares analyses can be applied. Several criteria are given to show when these techniques are useful in time-of-flight data analysis. 14 refs., 6 figs., 1 tab

Uses of reactor neutrons for studying the microcomposition of materials

International Nuclear Information System (INIS)

Jervis, R.E.

1993-01-01

Reactor neutrons constitute excellents 'probes' for exploring and measuring a wide range both of minor and trace constituents in solids and liquids with high sensitivity because of their transparency in materials. Nondestructive neutron prompt-gamma analysis (PGA) utilizing either cold or thermal neutrons, such as at JRR-3M, is compared and contrasted to the more common (delayed) instrumental neutron activation analysis (INAA) and epithermal NAA. Clearly PGA offers high sensitivity for selected elements: B, H, Cd and REE's in suitable matrices, and is therefore, complementary to INAA which is not as useful for them, or for Ni, Sn, Fe, C or N. Recent INAA applications in our laboratory that demonstrate some of the uniqueness of neutron methods include use of epithermal neutrons for small biological specimens to measure Cd, K, As, Zn and, multielemental INAA for environmental pollution studies. The latter involves large data sets of multielemental concentrations which are subjected to statistical multivariant factor analysis to reveal unknown or unsuspected quantitative relationships among groups of trace constituents. These patterns, or 'factors' are shown to be uniquely related to pollution sources and can be utilized to compute the relative source contributions at a given receptor site. (author)

Soil pollution with trace elements at selected sites in Romania studied by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Pantelica, A.; Carmo Freitas, M. do; Ene, A.; Steinnes, E.

2013-01-01

Instrumental neutron activation analysis (INAA) was used to determine concentrations of 42 elements in samples of surface soil collected at seven sites polluted from various anthropogenic activities and a control site in a relatively clean area. Elements studied were Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Gd, Hf, Hg, K, La, Lu, Mg, Mn, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, U, V, W, Yb, Zn, and Zr. The results are compared with data for trace elements atmospheric deposition in lichen transplants from the same sites. The most severe soil contamination was observed at Copsa Mica from non-ferrous metallurgy. Appreciable soil contamination was also indicated at Baia Mare (non-ferrous mining and metallurgy), Deva (coal-fired power plant, cement and building materials industry), Galati (ferrous metallurgy), Magurele and Afumati (general urban pollution), and Oradea (chemical and light industries). In most cases excessive levels of toxic metals in soils matched correspondingly high values in lichen transplants. Compared to Romanian norms, legal upper limits were exceeded for Zn and Cd at Copsa Mica. Also, As and Sb occurred in excessive levels at given sites. (orig.)

Soil pollution with trace elements at selected sites in Romania studied by instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Pantelica, A. [Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), Magurele, Ilfov County (Romania); Carmo Freitas, M. do [Technological and Nuclear Institute (ITN), Sacavem (Portugal); Ene, A. [Dunarea de Jos Univ. of Galati (Romania). Dept. of Chemistry, Physics and Environment; Steinnes, E. [Norwegian Univ. of Science and Technology, Trondheim (Norway). Dept. of Chemistry

2013-03-01

Instrumental neutron activation analysis (INAA) was used to determine concentrations of 42 elements in samples of surface soil collected at seven sites polluted from various anthropogenic activities and a control site in a relatively clean area. Elements studied were Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Eu, Fe, Gd, Hf, Hg, K, La, Lu, Mg, Mn, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, U, V, W, Yb, Zn, and Zr. The results are compared with data for trace elements atmospheric deposition in lichen transplants from the same sites. The most severe soil contamination was observed at Copsa Mica from non-ferrous metallurgy. Appreciable soil contamination was also indicated at Baia Mare (non-ferrous mining and metallurgy), Deva (coal-fired power plant, cement and building materials industry), Galati (ferrous metallurgy), Magurele and Afumati (general urban pollution), and Oradea (chemical and light industries). In most cases excessive levels of toxic metals in soils matched correspondingly high values in lichen transplants. Compared to Romanian norms, legal upper limits were exceeded for Zn and Cd at Copsa Mica. Also, As and Sb occurred in excessive levels at given sites. (orig.)

Elemental analysis of soil and hair sample by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Chung, Yong Sam; Quraishi, Shamshad Begum; Moon, Jong Hwa; Kim, Sun Ha; Baek, Sung Yeoil; Kang, Sang Hoon; Lim, Jong Myoung; Cho, Hyun Je; Kim, Young Jin

2004-03-01

Myanmar soil sample was analyzed by using the instrumental neutron activation analysis. The elemental concentrations in the sample, altogether 34 elements, Al As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Ga, Gd, Hf, Ir, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Se, Sm, Th, Ti, V, Yb, Zn and Zr were determined. The concentration of 17 elements (Al, Au, Br, Ca, Cl, Cr, Cu, Co, Fe, Hg, K, Na, Mn, Mg, Sb, Se, Zn) in human hair samples were determined by INAA For quality control of analytical method, certified reference material was used

Elemental analysis of soil and hair sample by instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Chung, Yong Sam; Quraishi, Shamshad Begum; Moon, Jong Hwa; Kim, Sun Ha; Baek, Sung Yeoil; Kang, Sang Hoon; Lim, Jong Myoung; Cho, Hyun Je; Kim, Young Jin

2004-03-01

Myanmar soil sample was analyzed by using the instrumental neutron activation analysis. The elemental concentrations in the sample, altogether 34 elements, Al As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Ga, Gd, Hf, Ir, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Se, Sm, Th, Ti, V, Yb, Zn and Zr were determined. The concentration of 17 elements (Al, Au, Br, Ca, Cl, Cr, Cu, Co, Fe, Hg, K, Na, Mn, Mg, Sb, Se, Zn) in human hair samples were determined by INAA For quality control of analytical method, certified reference material was used.

Proceedings of the workshop on neutron instrumentation for a long-pulse spallation source

International Nuclear Information System (INIS)

Alonso, J.; Schroeder, L.; Pynn, R.

1995-01-01

This workshop was carried out under the auspices of the Lawrence Berkeley National Laboratory Pulsed Spallation Source activity and its Pulsed Spallation Source Committee (PSSC). One of our activities has been the sponsorship of workshops related to neutron production by pulsed sources. At the Crystal City PSSC meeting a decision was made to hold a workshop on the instrumentation opportunities at a long-pulse spallation source (LPSS). The enclosed material represents the results of deliberations of the three working groups into which the participants were divided, covering elastic scattering, inelastic scattering and fundamental physics, as well as contributions from individual participants. We hope that the material in this report will be useful to the neutron scattering community as it develops a road-map for future neutron sources. The workshop was held at LBNL in mid-April with about sixty very dedicated participants from the US and abroad. This report presents the charge for the workshop: Based on the bench mark source parameters provided by Gary Russell, determine how a suite of spectrometers in each of the three working group's area of expertise would perform at an LPSS and compare this performance with that of similar spectrometers at a continuous source or a short-pulse source. Identify and discuss modifications to these spectrometers that would enhance their performance at an LPSS. Identify any uncertainties in the analysis of spectrometer performance that require further research. Describe what R ampersand D is needed to resolve these issues. Discuss how the performance of instruments would be affected by changes in source parameters such as repetition rate, proton pulse length, and the characteristic time of pulse tails. Identify beneficial changes that could become goals for target/moderator designers. Identify novel methods that might be applied at an LPSS. Selected papers are indexed separately for inclusion in the Energy Science and Technology

Study of a high spatial resolution {sup 10}B-based thermal neutron detector for application in neutron reflectometry: the Multi-Blade prototype

Energy Technology Data Exchange (ETDEWEB)

Piscitelli, F; Buffet, J C; Clergeau, J F; Cuccaro, S; Guérard, B; Khaplanov, A; Manna, Q La; Rigal, J M; Esch, P Van, E-mail: piscitelli@ill.fr [Institut Laue-Langevin (ILL), 6, Jules Horowitz, 38042, Grenoble (France)

2014-03-01

Although for large area detectors it is crucial to find an alternative to detect thermal neutrons because of the {sup 3}He shortage, this is not the case for small area detectors. Neutron scattering science is still growing its instruments' power and the neutron flux a detector must tolerate is increasing. For small area detectors the main effort is to expand the detectors' performances. At Institut Laue-Langevin (ILL) we developed the Multi-Blade detector which wants to increase the spatial resolution of {sup 3}He-based detectors for high flux applications. We developed a high spatial resolution prototype suitable for neutron reflectometry instruments. It exploits solid {sup 10}B-films employed in a proportional gas chamber. Two prototypes have been constructed at ILL and the results obtained on our monochromatic test beam line are presented here.

Russia: Overview of activities on Neutron Imaging (NI) and Cultural Heritage (CH) studies

International Nuclear Information System (INIS)

Kozlenko, Denis

2012-01-01

The development of neutron imaging techniques as a tool for non-destructive analysis of the internal structure, defects and processes in industrial products, functional materials, objects of cultural heritage attracts considerable attention at the present time. The dedicated instruments are available at the many neutron sources. The IBR-2M high flux pulsed reactor is one of the most powerful pulsed neutron sources in the world with the average power 2 MW, power per neutron pulse 1850 MW and neutron flux in pulse of 5·10 15 n/cm 2 /s. During the period December 2006 – December 2010 the reactor was on modernization for replacement of the reactor vessel and fuel elements. During 2011, the successful physical and power start-up of IBR-2M were performed. Now reactor is operational and can be used for research and development activities using neutron scattering techniques in next 25 years prospective. However, no instruments dedicated for neutron imaging is installed at IBR-2M so far. Moreover, in Russian Federation there is no dedicated neutron imaging facility for cultural heritage research at the moment

Study of radionuclide and element characterization of Angola marine sediment using low background gamma spectrometry and instrumental neutron activation analysis techniques

International Nuclear Information System (INIS)

Teixeira, M.C.P.; Vuong Huu Tan; Truong Y; Ho Manh Dung; Le Nhu Sieu; Cao Dong Vu; Nguyen Thanh Binh

2007-01-01

The concentrations of radionuclides and chemical elements in Angola marine sediment samples were determined by using low background gamma (LBG) spectrometry and instrumental neutron activation analysis (INAA). The combination of radionuclide and elemental concentration values yielded synergy in the validation of analytical data and identification of sediment sources modeled by multivariate factor analysis. Varimax rotation factor analysis based on the elemental concentrations revealed five sources contributed to the sediment composition, i.e. crustal, sea-salt, industrial, coal-related and Se-related sources. (author)

Application of thin-film breakdown counters for characterization of neutron field of the VESUVIO instrument at the ISIS spallation source

Science.gov (United States)

Smirnov, A. N.; Pietropaolo, A.; Prokofiev, A. V.; Rodionova, E. E.; Frost, C. D.; Ansell, S.; Schooneveld, E. M.; Gorini, G.

2012-09-01

The high-energy neutron field of the VESUVIO instrument at the ISIS facility has been characterized using the technique of thin-film breakdown counters (TFBC). The technique utilizes neutron-induced fission reactions of natU and 209Bi with detection of fission fragments by TFBCs. Experimentally determined count rates of the fragments are ≈50% higher than those calculated using spectral neutron flux simulated with the MCNPX code. This work is a part of the project to develop ChipIr, a new dedicated facility for the accelerated testing of electronic components and systems for neutron-induced single event effects in the new Target Station 2 at ISIS. The TFBC technique has shown to be applicable for on-line monitoring of the neutron flux in the neutron energy range 1-800 MeV at the position of the device under test (DUT).

Application of thin-film breakdown counters for characterization of neutron field of the VESUVIO instrument at the ISIS spallation source

International Nuclear Information System (INIS)

Smirnov, A.N.; Pietropaolo, A.; Prokofiev, A.V.; Rodionova, E.E.; Frost, C.D.; Ansell, S.; Schooneveld, E.M.; Gorini, G.

2012-01-01

The high-energy neutron field of the VESUVIO instrument at the ISIS facility has been characterized using the technique of thin-film breakdown counters (TFBC). The technique utilizes neutron-induced fission reactions of nat U and 209 Bi with detection of fission fragments by TFBCs. Experimentally determined count rates of the fragments are ≈50% higher than those calculated using spectral neutron flux simulated with the MCNPX code. This work is a part of the project to develop ChipIr, a new dedicated facility for the accelerated testing of electronic components and systems for neutron-induced single event effects in the new Target Station 2 at ISIS. The TFBC technique has shown to be applicable for on-line monitoring of the neutron flux in the neutron energy range 1–800 MeV at the position of the device under test (DUT).

Instrument and method for focusing X-rays, gamma rays and neutrons

International Nuclear Information System (INIS)

1982-01-01

A crystal diffraction instrument is described with an improved crystalline structure having a face for receiving a beam of photons or neutrons and diffraction planar spacing along that face with the spacing increasing progressively along the face to provide a decreasing Bragg angle and thereby increasing the usable area and acceptance angle. The increased planar spacing is provided by the use of a temperature differential across the crystalline structure, by assembling a plurality of crystalline structure with different compositions, by an individual crystalline structure with a varying composition and thereby a changing planar spacing along its face, and by combinations of these techniques. (Auth.)

Californium interrogation prompt neutron (CIPN) instrument for non-destructive assay of spent nuclear fuel—Design concept and experimental demonstration

International Nuclear Information System (INIS)

Henzlova, D.; Menlove, H.O.; Rael, C.D.; Trellue, H.R.; Tobin, S.J.; Park, Se-Hwan; Oh, Jong-Myeong; Lee, Seung-Kyu; Ahn, Seong-Kyu; Kwon, In-Chan; Kim, Ho-Dong

2016-01-01

This paper presents results of the first experimental demonstration of the Californium Interrogation Prompt Neutron (CIPN) instrument developed within a multi-year effort launched by the Next Generation Safeguards Initiative Spent Fuel Project of the United States Department of Energy. The goals of this project focused on developing viable non-destructive assay techniques with capabilities to improve an independent verification of spent fuel assembly characteristics. For this purpose, the CIPN instrument combines active and passive neutron interrogation, along with passive gamma-ray measurements, to provide three independent observables. This paper describes the initial feasibility demonstration of the CIPN instrument, which involved measurements of four pressurized-water-reactor spent fuel assemblies with different levels of burnup and two initial enrichments. The measurements were performed at the Post-Irradiation Examination Facility at the Korea Atomic Energy Institute in the Republic of Korea. The key aim of the demonstration was to evaluate CIPN instrument performance under realistic deployment conditions, with the focus on a detailed assessment of systematic uncertainties that are best evaluated experimentally. The measurements revealed good positioning reproducibility, as well as a high degree of insensitivity of the CIPN instrument's response to irregularities in a radial burnup profile. Systematic uncertainty of individual CIPN instrument signals due to assembly rotation was found to be <4.5%, even for assemblies with fairly extreme gradients in the radial burnup profile. These features suggest that the CIPN instrument is capable of providing a good representation of assembly average characteristics, independent of assembly orientation in the instrument.

Californium interrogation prompt neutron (CIPN) instrument for non-destructive assay of spent nuclear fuel—Design concept and experimental demonstration

Energy Technology Data Exchange (ETDEWEB)

Henzlova, D., E-mail: henzlova@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Menlove, H.O.; Rael, C.D.; Trellue, H.R.; Tobin, S.J. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Park, Se-Hwan; Oh, Jong-Myeong; Lee, Seung-Kyu; Ahn, Seong-Kyu; Kwon, In-Chan; Kim, Ho-Dong [Korea Atomic Energy Research Institute, Daejeong (Korea, Republic of)

2016-01-11

This paper presents results of the first experimental demonstration of the Californium Interrogation Prompt Neutron (CIPN) instrument developed within a multi-year effort launched by the Next Generation Safeguards Initiative Spent Fuel Project of the United States Department of Energy. The goals of this project focused on developing viable non-destructive assay techniques with capabilities to improve an independent verification of spent fuel assembly characteristics. For this purpose, the CIPN instrument combines active and passive neutron interrogation, along with passive gamma-ray measurements, to provide three independent observables. This paper describes the initial feasibility demonstration of the CIPN instrument, which involved measurements of four pressurized-water-reactor spent fuel assemblies with different levels of burnup and two initial enrichments. The measurements were performed at the Post-Irradiation Examination Facility at the Korea Atomic Energy Institute in the Republic of Korea. The key aim of the demonstration was to evaluate CIPN instrument performance under realistic deployment conditions, with the focus on a detailed assessment of systematic uncertainties that are best evaluated experimentally. The measurements revealed good positioning reproducibility, as well as a high degree of insensitivity of the CIPN instrument's response to irregularities in a radial burnup profile. Systematic uncertainty of individual CIPN instrument signals due to assembly rotation was found to be <4.5%, even for assemblies with fairly extreme gradients in the radial burnup profile. These features suggest that the CIPN instrument is capable of providing a good representation of assembly average characteristics, independent of assembly orientation in the instrument.

Neutron scattering equipments in JAERI. Current status

International Nuclear Information System (INIS)

Hamaguchi, Yoshikazu; Minakawa, Nobuaki

2003-01-01

24 neutron scattering instruments are installed in the JRR-3M research reactor. Among them JAERI has 12 neutron scattering instruments. Those instruments are HRPD for high-resolution structural analysis, TAS-1 and TAS-2 for elastic and inelastic scattering and for magnetic scattering measurements by the polarized neutron, LTAS for elastic and inelastic scattering measurement at a low energy region, and for neutron device development, PNO for topography and for very small angle scattering measurement in a small Q range, NRG for neutron radiography, RESA for internal strain measurements, SANS for the molecule and semi-macroscopic magnetic structural analysis, BIX-2 and BIX-3 for the biological structural analysis research, and PGA for the research of prompt gamma-ray analysis. The university groups have 12 neutron scattering instruments. Since those instruments were installed at the period when JRR-3M was completed, about 10 years have passed. In order to match the old control systems with the progress of recent computer technologies, and peripheral equipment, numbers of instruments are being renewed. In the neutron guide hall of JRR-3M, the Ni mirror guide tube was replaced by a super mirror guide tube to increase neutron flux. The intensity of 2A flux was increased by a factor of about two. (J.P.N.)

Trace element determination in beauty products by k0-instrumental neutron activation analysis

International Nuclear Information System (INIS)

Sneyers, L.; Verheyen, L.; Vermaercke, P.; Bruggeman, M.

2009-01-01

A recent study on trace elements in beauty products and cosmetics sold on the Asian market has shown the presence of high levels of U, Th and rare earth elements in so called 'Hormesis cosmetics'. For the purpose of comparison, some more information about trace elements in European cosmetics would be useful. In this paper the results obtained using k 0 -standardised Instrumental Neutron Activation Analysis (k 0 -INAA) for more than 20 trace elements in 20 different beauty products collected from the European market are presented. We found traces of Ba, As and Sb which is in breach with European legislation. For some of the other elements like Cr and Co further speciation is needed in order to evaluate their presence in beauty products. (author)

Iron Quadrangle, Brazil. Elemental concentration determined by k0-instrumental neutron activation analysis. Part 1. Soil samples

International Nuclear Information System (INIS)

Menezes, M.A.B.C.; Palmieri, H.E.L.; Leonel, L.V.; Nalini, H.A.Jr.; Jacimovic, R.

2006-01-01

The Iron Quadrangle, Minas Gerais, Brazil, is rich in mineral occurrences and is considered one of the richest mineral-bearing regions in the world. Most investigations in this region have dealt with the determination of arsenic and mercury but so far few studies have been carried out aiming at determining other important elements. Having in mind the potential risk caused by mineral activities, this study was developed in order to assess the potential influence of the soil on foodstuffs. The soil samples were collected from three sites inside and outside the Iron Quadrangle. The samples were analyzed at the Laboratory for Neutron Activation Analysis, CDTN/CNEN by the k 0 -instrumental neutron activation analysis. This paper reports the elemental concentration determined in soil and emphasises the elements cited in the Brazilian environmental legislation for soil. This work also confirms the high elemental concentration of several minerals, however, it is difficult to distinguish the contamination from anthropogenic activities from the natural occurrence. (author)

Trace elements in cigarette tobacco by a method of instrumental neutron activation analysis

International Nuclear Information System (INIS)

Noordin Ibrahim

1986-01-01

A total of ten cigarette brands were investigated for determining the trace elemental concentrations in tobacco so as to assess their role in the induction of related diseases through smoking. A method instrumental Neutron Activation analysis was employed due to high sensitivity, speed and ability to analyse sample for a wide spectrum of elements simultaneously. A total of 18 elements were detected of which the majority are toxic elements. A full result and conclusion will be reported in the forthcoming paper. (A.J.)

Instrumental neutron activation analysis of rib bone samples and of bone reference materials

International Nuclear Information System (INIS)

Saiki, M.; Takata, M.K.; Kramarski, S.; Borelli, A.

2000-01-01

The instrumental neutron activation analysis method was used for the determination of trace elements in rib bone samples taken from autopsies of accident victims. The elements Br, Ca, Cl, Cr, Fe, Mg, Mn, Na, P, Sr, Rb and Zn were determined in cortical tissues by using short and long irradiations with thermal neutron flux of the IEA-R1m nuclear reactor. The reference materials NIST SRM 1400 Bone Ash and NIST SRM 1486 Bone Meal were also analyzed in order to evaluate the precision and the accuracy of the results. It was verified that lyophilization is the most convenient process for drying bone samples since it does not cause any element losses. Comparisons were made between the results obtained for rib samples and the literature values as well as between the results obtained for different ribs from a single individual and for bones from different individuals. (author)

Practical course on reactor instrumentation

International Nuclear Information System (INIS)

Boeck, H.; Villa, M.

2004-06-01

This course is based on the description of the instrumentation of the TRIGA-reactor Vienna, which is used for training research and isotope production. It comprises the following chapters: 1. instrumentation, 2. calibration of the nuclear channels, 3. rod drop time of the control rods, 4. neutron flux density measurements using compensated ionization, 5. neutron flux density measurement with fission chambers (FC), 6. neutron flux density measurement with self-powered neutron detectors (SPND), 7. pressurized water reactor simulator, 8. verification of the radiation level during reactor operation. There is one appendix about neutron-sensitive thermocouples. (nevyjel)

Instrumental Neutron Activation Analysis applied to the study of chemical element accumulation in organs of Rhinella schneideri (Werner, 1894)

Energy Technology Data Exchange (ETDEWEB)

Bardini Junior, Claudiney; Fernandes, Elisabete A. de Nadai, E-mail: lis@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Santos, Katarine M. Barbosa; Silva Neto, Luiz J. da; Santos, Robson A. dos; Silva, Karolayne E.M.; França, Elvis J. de, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciências Nucleares do Nordeste (DIAMB/CRCN-NE/CNEN-PE), Recife, PE (Brazil). Div. de Monitoração Ambiental

2017-07-01

Instrumental Neutron Activation Analysis (INAA) is a multielementar technique with high sensitivity, and can be applied to study small samples. Therefore, this research proposes using the INAA for quantifying the accumulation of chemical elements in organs of anuran amphibians Rhinella schneideri (Werner, 1894). Male individuals were collected on areas with anthropogenic influence close to water resources on the campus of ESALQ/USP in 2009. The animals were sacrificed in a cold chamber and dissected to separate their kidneys, livers, lungs and skins. After cleaning, the organs were lyophilized and pulverized. Samples weighing from 200 to 500 mg were placed in polyethylene capsules to be irradiated. The INAA technique, based on the bombardment of samples with neutrons for the production of radionuclides, was applied using the Nuclear Research Reactor of the Nuclear and Energy Research Institute. Portions of certified reference materials were used to evaluate the quality of the analytical procedure. The mass fractions were quantified by the k0 method, and the results indicated differences among the As, Br, Co, Cr, Fe, Hg, Sc, Se and Zn concentrations in the analyzed organs. Therefore, it was possible to calculate the bioaccumulation indexes relative to these chemical elements for the species. In addition, it was possible to infer the contamination pathways: As, Br, Co, Cr and Se by ingestion and Co, Fe, Hg, Sc and Zn by contact, which corroborated the usage of R. schneideri anuran as a biomonitor of chemical elements. (author)

Instrumental Neutron Activation Analysis applied to the study of chemical element accumulation in organs of Rhinella schneideri (Werner, 1894)

International Nuclear Information System (INIS)

Bardini Junior, Claudiney; Fernandes, Elisabete A. de Nadai; Santos, Katarine M. Barbosa; Silva Neto, Luiz J. da; Santos, Robson A. dos; Silva, Karolayne E.M.; França, Elvis J. de

2017-01-01

Instrumental Neutron Activation Analysis (INAA) is a multielementar technique with high sensitivity, and can be applied to study small samples. Therefore, this research proposes using the INAA for quantifying the accumulation of chemical elements in organs of anuran amphibians Rhinella schneideri (Werner, 1894). Male individuals were collected on areas with anthropogenic influence close to water resources on the campus of ESALQ/USP in 2009. The animals were sacrificed in a cold chamber and dissected to separate their kidneys, livers, lungs and skins. After cleaning, the organs were lyophilized and pulverized. Samples weighing from 200 to 500 mg were placed in polyethylene capsules to be irradiated. The INAA technique, based on the bombardment of samples with neutrons for the production of radionuclides, was applied using the Nuclear Research Reactor of the Nuclear and Energy Research Institute. Portions of certified reference materials were used to evaluate the quality of the analytical procedure. The mass fractions were quantified by the k0 method, and the results indicated differences among the As, Br, Co, Cr, Fe, Hg, Sc, Se and Zn concentrations in the analyzed organs. Therefore, it was possible to calculate the bioaccumulation indexes relative to these chemical elements for the species. In addition, it was possible to infer the contamination pathways: As, Br, Co, Cr and Se by ingestion and Co, Fe, Hg, Sc and Zn by contact, which corroborated the usage of R. schneideri anuran as a biomonitor of chemical elements. (author)

Application of thin-film breakdown counters for characterization of neutron field of the VESUVIO instrument at the ISIS spallation source

Energy Technology Data Exchange (ETDEWEB)

Smirnov, A.N. [V.G. Khlopin Radium Institute, St. Petersburg (Russian Federation); Pietropaolo, A., E-mail: antonino.pietropaolo@roma2.infn.it [CNISM UdR Tor Vergata, and Centro NAST Roma, Italy Scientifica 1 I-00133 Roma Italy (Italy); Prokofiev, A.V. [The Svedberg Laboratory, Uppsala University, Uppsala (Sweden); Rodionova, E.E. [V.G. Khlopin Radium Institute, St. Petersburg (Russian Federation); Frost, C.D.; Ansell, S.; Schooneveld, E.M. [ISIS Facility, Rutherford Appleton Laboratory, Chilton (United Kingdom); Gorini, G. [Dipartimento di Fisica ' G. Occhialini,' Universita degli Studi di Milano-Bicocca, Milano (Italy)

2012-09-21

The high-energy neutron field of the VESUVIO instrument at the ISIS facility has been characterized using the technique of thin-film breakdown counters (TFBC). The technique utilizes neutron-induced fission reactions of {sup nat}U and {sup 209}Bi with detection of fission fragments by TFBCs. Experimentally determined count rates of the fragments are Almost-Equal-To 50% higher than those calculated using spectral neutron flux simulated with the MCNPX code. This work is a part of the project to develop ChipIr, a new dedicated facility for the accelerated testing of electronic components and systems for neutron-induced single event effects in the new Target Station 2 at ISIS. The TFBC technique has shown to be applicable for on-line monitoring of the neutron flux in the neutron energy range 1-800 MeV at the position of the device under test (DUT).

Neutron response study

International Nuclear Information System (INIS)

Endres, G.W.R.; Fix, J.J.; Thorson, M.R.; Nichols, L.L.

1981-01-01

Neutron response of the albedo type dosimeter is strongly dependent on the energy of the incident neutrons as well as the moderating material on the backside of the dosimeter. This study characterizes the response of the Hanford dosimeter for a variety of neutron energies for both a water and Rando phantom (a simulated human body consisting of an actual human skeleton with plastic for body muscles and certain organs). The Hanford dosimeter response to neutrons of different energies is typical of albedo type dosimeters. An approximate two orders of magnitude difference in response is observed between neutron energies of 100 keV and 10 MeV. Methods were described to compensate for the difference in dosimeter response between a laboratory neutron spectrum and the different spectra encountered at various facilities in the field. Generally, substantial field support is necessary for accurate neutron dosimetry

Characterization of ophiolites from northern Havana-Matanzas petroleum fields using instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Montero Cabrera, M.E. E-mail: montero@yakko.cimav.edu.mx; Ortueta Milan, M.; Herrera Peraza, E.F.; Herrera Hernandez, H.; Rodriguez Martinez, N.; Olivares Rieumont, S.; Lopez Reyes, M.C

2001-01-15

Concentrations of 16 elements from 14 serpentinitic samples from Basilio and Cantel petroleum fields were obtained by instrumental neutron activation analysis (INAA): Cr, Co, Ni, La, Nd, Sm, Eu, Gd, Tb, Ce Yb, Lu, Rb, Cs, Hf and Th. Relative INAA was performed using certified reference materials and laboratory standards. Average elemental concentrations showed that the ophiolites have a basic character, suggesting the use of a well-logging method designed for volcano-sedimentary petroleum fields.

Characterization of ophiolites from northern Havana-Matanzas petroleum fields using instrumental neutron activation analysis

International Nuclear Information System (INIS)

Montero Cabrera, M.E.; Ortueta Milan, M.; Herrera Peraza, E.F.; Herrera Hernandez, H.; Rodriguez Martinez, N.; Olivares Rieumont, S.; Lopez Reyes, M.C.

2001-01-01

Concentrations of 16 elements from 14 serpentinitic samples from Basilio and Cantel petroleum fields were obtained by instrumental neutron activation analysis (INAA): Cr, Co, Ni, La, Nd, Sm, Eu, Gd, Tb, Ce Yb, Lu, Rb, Cs, Hf and Th. Relative INAA was performed using certified reference materials and laboratory standards. Average elemental concentrations showed that the ophiolites have a basic character, suggesting the use of a well-logging method designed for volcano-sedimentary petroleum fields

Pressure/temperature fluid cell apparatus for the neutron powder diffractometer instrument: Probing atomic structure in situ

Energy Technology Data Exchange (ETDEWEB)

Wang, Hsiu-Wen; Fanelli, Victor R.; Reiche, Helmut M.; Larson, Eric; Taylor, Mark A.; Siewenie, Joan [Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Xu, Hongwu [Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Zhu, Jinlong [High Pressure Science and Engineering Center, Department of Physics and Astronomy, The University of Nevada, Las Vegas, Nevada 89154, USA and National Lab for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Page, Katharine, E-mail: pagekl@ornl.gov [Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2014-12-15

This contribution describes a new local structure compatible gas/liquid cell apparatus for probing disordered materials at high pressures and variable temperatures in the Neutron Powder Diffraction instrument at the Lujan Neutron Scattering Center, Los Alamos National Laboratory. The new sample environment offers choices for sample canister thickness and canister material type. Finite element modeling is utilized to establish maximum allowable working pressures of 414 MPa at 15 K and 121 MPa at 600 K. High quality atomic pair distribution function data extraction and modeling have been demonstrated for a calibration standard (Si powder) and for supercritical and subcritical CO{sub 2} measurements. The new sample environment was designed to specifically target experimental studies of the local atomic structures involved in geologic CO{sub 2} sequestration, but will be equally applicable to a wide variety of energy applications, including sorption of fluids on nano/meso-porous solids, clathrate hydrate formation, catalysis, carbon capture, and H{sub 2} and natural gas uptake/storage.

Toenail elemental analysis of Korean young adults by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Lee, O.

2016-01-01

The element contents in toenail clippings of healthy Korean young adults were measured using an instrumental neutron activation analysis. The average contents of elements such as Na, K, Cl, Ca, Fe, Se, and Zn are 449, 474, 1024, 1677, 66, 0.7 and 94 mg/kg in men, whereas those contents in women respectively 332, 476, 836, 1097, 66, 0.8 and 104 mg/kg. The correlation analysis of toenail elements with chronic disease risks showed positive associations between Na and serum HDL-cholesterol, blood pressure, and negative associations between Se and Hs-CRP, between Zn and hemoglobin level. (author)

Trace elements evaluation of some medicinal herbs by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Zaidi, J.H.; Fatima, I.; Qureshi, I.H.; Subhani, M.S.

2004-01-01

Instrumental neutron activation analysis has been used for the analysis of seven varieties of medicinal herbs generally used by the people of South Asian region. Twenty-one trace elements (essential, toxic and non-essential) were determined. This data should not only be helpful in establishing the base-line values in these medicinal herbs but also in correlating their role as therapeutic agents. A comparison of our data with literature values shows variation in trace element contents of same species of different origin which can be attributed to ecological and geographical variations to some extent; however an exact interpretation demands further extensive investigations. (orig.)

A digital data acquisition system for a time of flight neutron diffuse scattering instrument

International Nuclear Information System (INIS)

Venegas, Rafael; Bacza, Lorena; Navarro, Gustavo

1998-01-01

Full text. We describe the design of a digital data acquisition system built for acquiring and storing the information produced by a neutron diffuse scattering apparatus. This instrument is based on the analysis of pulsed subthermal neutron which are scattered by a solid or liquid sample, measured as function of the scattered neutron wavelength and momentum direction. The time of flight neutron intensities on 14 different angular detector positions and two fission chambers must be analyzed simultaneously for each neutron burst. A PC controlled data acquisition board system was built based on two parallel multiscannning units, each with its own add-one counting unit, and a common base time generator. The unit plugs onto the ISA bus through an interface card. Two separate counting units were designed, to avoid possible access competition between low counting rate counters at off-axis positions and the higher rate frontal 0 deg and beam monitoring counters. the first unit contains logic for 14 independent and simultaneous multi scaling inputs, with 128 time channels and dwell time per channel of 5, 10 or 20 microseconds. Sweep trigger is synchronized with an electric signal from a coil sensing the rotor. The second unit contains logic for four additional multi scalers using the same external synchronizing signal, similar in all others details to the previously described multi scalers. Basic control routines for the acquisitions were written in C and a program for spectrum display and user interface was written in C ++ for a Windows 3.1 OS. A block diagram of the system is presented

Comparison of Elemental Composition in Korean Irradiated Foods using Instrumental Neutron Activation Analysis

International Nuclear Information System (INIS)

Chung, Yong Sam; Kim, Sun Ha; Sun, Gwang Min; Lim, Jong Myung; Moon, Jong Hwa; Lee, Kye Hong; Kim, Young Jin; Choi, Jong Il; Lee, Joo Eun

2010-01-01

The information and role of trace mineral elements from an intake of created and processed foodstuff are important as a indicator of human health and nutritional parameter, as well as a quality control of food and diet. Particularly, special food created for consumption by astronauts in outer space may differ with common food on the earth in order to compensate a decrease of taste and nutrition by strong cosmic rays, a state of nongravitation, low pressure, and enclosed space environment. In April 2008, Korea's first astronaut became a crew member of the international space station and she was brought special space versions of Korea's national dishes such as Kimchi, boiled rice, hot red paste, green tea, ramyun, and so on. Accurate quantitative analysis of trace elements in various kinds of biological samples is also important for data quality. Neutron activation analysis is a sensitive, non-destructive, multi-elemental analytical method, and is proper for tracing elements in a biological sample in order to avoid loss and contamination by chemical pretreatment. This study analyses the distribution of concentrations for both essential and toxic elements in six kinds of Korean space foods developed by KAERI. The quantitative analytical results from instrumental neutron activation analysis are presented

Symposium on neutron scattering

International Nuclear Information System (INIS)

Lehmann, M.S.; Saenger, W.; Hildebrandt, G.; Dachs, H.

1984-01-01

Extended abstracts of the named symposium are presented. The first part of this report contains the abstracts of the lectures, the second those of the posters. Topics discussed on the symposium include neutron diffraction and neutron scattering studies in magnetism, solid state chemistry and physics, materials research. Some papers discussing instruments and methods are included too. (GSCH)

Beyond Californium-A Neutron Generator Alternative for Dosimetry and Instrument Calibration in the U.S.

Science.gov (United States)

Piper, Roman K; Mozhayev, Andrey V; Murphy, Mark K; Thompson, Alan K

2017-09-01

Evaluations of neutron survey instruments, area monitors, and personal dosimeters rely on reference neutron radiations, which have evolved from the heavy reliance on (α,n) sources to a shared reliance on (α,n) and the spontaneous fission neutrons of californium-252 (Cf). Capable of producing high dose equivalent rates from an almost point source geometry, the characteristics of Cf are generally more favorable when compared to the use of (α,n) and (γ,n) sources or reactor-produced reference neutron radiations. Californium-252 is typically used in two standardized configurations: unmoderated, to yield a fission energy spectrum; or with the capsule placed within a heavy-water moderating sphere to produce a softened spectrum that is generally considered more appropriate for evaluating devices used in nuclear power plant work environments. The U.S. Department of Energy Cf Loan/Lease Program, a longtime origin of affordable Cf sources for research, testing and calibration, was terminated in 2009. Since then, high-activity sources have become increasingly cost-prohibitive for laboratories that formerly benefited from that program. Neutron generators, based on the D-T and D-D fusion reactions, have become economically competitive with Cf and are recognized internationally as important calibration and test standards. Researchers from the National Institute of Standards and Technology and the Pacific Northwest National Laboratory are jointly considering the practicality and technical challenges of implementing neutron generators as calibration standards in the U.S. This article reviews the characteristics of isotope-based neutron sources, possible isotope alternatives to Cf, and the rationale behind the increasing favor of electronically generated neutron options. The evaluation of a D-T system at PNNL has revealed characteristics that must be considered in adapting generators to the task of calibration and testing where accurate determination of a dosimetric quantity is

Determination of essential elements in commercial baby foods by INAA (Instrumental Neutron Activation Analysis)

International Nuclear Information System (INIS)

Vallinoto, Priscila; Maihara, Vera A.

2011-01-01

The World Health Organization recommends that infants be breast feed exclusively at least six months after birth. After this period, it is recommended to introduce complementary foods, in order to meet nutritional amounts, minerals and energy needs of children. Commercial food products intended for infants form an important part of the diet for many babies, so it is very important that such food contains sufficient amounts of minerals. Inadequate complementary feeding is a major cause of high rates of malnutrition in developing countries. In this study, essential elements: Ca, Co, Cr, Cs, Fe, K, Na and Zn levels were determined in seven different commercial food products samples by Instrumental Neutron Activation Analysis. The seven baby food samples were acquired in the markets of Sao Paulo city. After 8-hour irradiations in the IEA-R1 nuclear research reactor under a thermal neutron flux of 10 12 n cm -2 s -1 , the essential elements were determined and the concentrations obtained were lower than the WHO requirements. For validation of the methodology, INCT MPH-2 Mixed Polish Herbs and NIST SRM 1577 b Bovine Liver were analysed. (author)

Determination of essential elements in commercial baby foods by INAA (Instrumental Neutron Activation Analysis)

Energy Technology Data Exchange (ETDEWEB)

Vallinoto, Priscila; Maihara, Vera A., E-mail: pvallinoto@ipen.br, E-mail: vmaihara@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

The World Health Organization recommends that infants be breast feed exclusively at least six months after birth. After this period, it is recommended to introduce complementary foods, in order to meet nutritional amounts, minerals and energy needs of children. Commercial food products intended for infants form an important part of the diet for many babies, so it is very important that such food contains sufficient amounts of minerals. Inadequate complementary feeding is a major cause of high rates of malnutrition in developing countries. In this study, essential elements: Ca, Co, Cr, Cs, Fe, K, Na and Zn levels were determined in seven different commercial food products samples by Instrumental Neutron Activation Analysis. The seven baby food samples were acquired in the markets of Sao Paulo city. After 8-hour irradiations in the IEA-R1 nuclear research reactor under a thermal neutron flux of 10{sup 12} n cm{sup -2} s{sup -1}, the essential elements were determined and the concentrations obtained were lower than the WHO requirements. For validation of the methodology, INCT MPH-2 Mixed Polish Herbs and NIST SRM 1577{sup b} Bovine Liver were analysed. (author)

Proceedings of the Oak Ridge National Laboratory/Brookhaven National Laboratory workshop on neutron scattering instrumentation at high-flux reactors

International Nuclear Information System (INIS)

McBee, M.R.; Axe, J.D.; Hayter, J.B.

1990-07-01

For the first three decades following World War II, the US, which pioneered the field of neutron scattering research, enjoyed uncontested leadership in the field. By the mid-1970's, other countries, most notably through the West European consortium at Institut Laue-Langevin (ILL) in Grenoble, France, had begun funding neutron scattering on a scale unmatched in this country. By the early 1980's, observers charged with defining US scientific priorities began to stress the need for upgrading and expansion of US research reactor facilities. The conceptual design of the ANS facility is now well under way, and line-item funding for more advanced design is being sought for FY 1992. This should lead to a construction request in FY 1994 and start-up in FY 1999, assuming an optimal funding profile. While it may be too early to finalize designs for instruments whose construction is nearly a decade removed, it is imperative that we begin to develop the necessary concepts to ensure state-of-the-art instrumentation for the ANS. It is in this context that this Instrumentation Workshop was planned. The workshop touched upon many ideas that must be considered for the ANS, and as anticipated, several of the discussions and findings were relevant to the planning of the HFBR Upgrade. In addition, this report recognizes numerous opportunities for further breakthroughs on neutron instrumentation in areas such as improved detection schemes (including better tailored scintillation materials and image plates, and increased speed in both detection and data handling), in-beam monitors, transmission white beam polarizers, multilayers and supermirrors, and more. Each individual report has been cataloged separately

Determination of trace elements in fisheries samples by instrumental neutron and photon activation analysis

International Nuclear Information System (INIS)

Chattopadhyay, A.; Ellis, K.M.; Nimalasiri Desilva, K.

1979-01-01

An instrumental neutron activation analysis (INAA) method has been developed for the simultaneous determination of trace concentrations of up to 23 elements in fisheries samples. The INAA method consists of irradiations of wet and lyophilized cod muscle and liver samples for three different periods at a flux density of 5x10 11 n.cm -2 .s -1 and subsequent measurements after four different decay periods using high-resolution Ge(Li) gamma-ray spectrometry. Concentrations of several essential and toxic elements have been determined. Loss of certain elements during lyophilization has been studied. Elemental distribution in muscles and livers as a function of the age of fish has been investigated. Precision and accuracy of the INAA method have been evaluated by analysing replicate samples, National Bureau of Standards' bovine liver standard reference material, and an intercalibration fish flour sample provided by the International Council for the Exploration of the Sea. A few fish samples have also been analysed by an alternative method, namely instrumental photon activation analysis (IPAA). Elemental concentrations determined by both INAA and IPAA methods are reported here. (author)

Study on neutron dosimetry in JNC Tokai Works

Energy Technology Data Exchange (ETDEWEB)

Tsujimura, Norio [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan). Tokai Works

2003-03-01

The author developed the neutron reference calibration fields using a {sup 252}Cf standard source surrounded with PMMA (polymethylmethacrylates) moderators at the Japan Nuclear Cycle Development Institute (JNC), Tokai Works. The moderators are concentric, annular cylinders made of lead-contained PMMA with a thickness of 13.5, 35.0, 59.5 and 77.0mm, and the {sup 252}Cf source is guided to the geometric center of moderators by the pneumatic system. These fields can provide the moderated neutron spectra very similar to those encountered around the globe-boxes of the fabrication process of MOX (PuO{sub 2}-UO{sub 2} mixed oxide) fuel. The neutron energy spectrum at the reference calibration point was evaluated from the calculations by MCNP4B and the measurements by the INS-type Bonner multi-sphere spectrometer and the hydrogen-filled proportional counters. The calculated neutron spectra were in good agreements with the measured ones. These fields were characterized in terms of the neutron fluence rate, spectral composition and ambient dose equivalent rate, and have served for the response-characterization of various neutron survey instruments. (author)

Study of Primary Cosmic Ray Electrons In Energy Range 10^11 - 10^13 Ev By Pamela Instrument.

Science.gov (United States)

Voronov, S.; Pamela Collaboration

The main goal of the magnetic spectrometer PAMELA is the study of antiparticle fluxes with energy up to 300 GeV in cosmic rays on board satellite. A modification of instrument was done by introducing of neutron detector. This device was placed under imaging calorimeter and bottom scintillator counter. It consists of two layers of 36 3He gas counters enveloped by a polyethylene moderator. The neutron detector gives additional possibility to identify the antiprotons going in aperture of spectrome- ter and generating the nuclear cascade in tungsten plates of calorimeter. This shower is followed by big number of neutrons in contrast to electromagnetic one caused by elec- tron or positron. From other side the combination of the imaging calorimeter, bottom scintillator and neutron detector constitute the independent instrument with large field of view which gives the possibility to measure the electron-positron cosmic ray com- ponent in energy range 1011-1013 eV with a rejection factor of order 10-4 regarding to nuclear one.

Neutron beam facilities at the Replacement Research Reactor, ANSTO

International Nuclear Information System (INIS)

Kim, S.

2003-01-01

The exciting development for Australia is the construction of a modern state-of-the-art 20-MW Replacement Research Reactor which is currently under construction to replace the aging reactor (HIFAR) at ANSTO in 2006. To cater for advanced scientific applications, the replacement reactor will provide not only thermal neutron beams but also a modern cold-neutron source moderated by liquid deuterium at approximately -250 deg C, complete with provision for installation of a hot-neutron source at a later stage. The latest 'supermirror' guides will be used to transport the neutrons to the Reactor Hall and its adjoining Neutron Guide Hall where a suite of neutron beam instruments will be installed. These new facilities will expand and enhance ANSTO's capabilities and performance in neutron beam science compared with what is possible with the existing HIFAR facilities, and will make ANSTO/Australia competitive with the best neutron facilities in the world. Eight 'leading-edge' neutron beam instruments are planned for the Replacement Research Reactor when it goes critical in 2006, followed by more instruments by 2010 and beyond. Up to 18 neutron beam instruments can be accommodated at the Replacement Research Reactor, however, it has the capacity for further expansion, including potential for a second Neutron Guide Hall. The first batch of eight instruments has been carefully selected in conjunction with a user group representing various scientific interests in Australia. A team of scientists, engineers, drafting officers and technicians has been assembled to carry out the Neutron Beam Instrument Project to successful completion. Today, most of the planned instruments have conceptual designs and are now being engineered in detail prior to construction and procurement. A suite of ancillary equipment will also be provided to enable scientific experiments at different temperatures, pressures and magnetic fields. This paper describes the Neutron Beam Instrument Project and gives

Instrumental neutron activation determination of gold in mineral raw materials using a californium neutron source

International Nuclear Information System (INIS)

Shilo, N.A.; Ippolitov, E.G.; Ivanenko, V.V.; Kustov, B.N.; Zheleznov, V.V.; Aristov, G.N.; Kovalenko, V.V.; Kondrat'ev, N.B.

1983-01-01

A facility using a californium neutron source and a method for the neutron activation analysis of gold were developed. The sensitivity of the determination is 0.1 g/t. The causes of random and systematic errors have been studied. It is concluded that in prospection and evaluation of gold ore deposists, the traditional test tube analysis for gold may be replaced with the developed method. (author)

Powder neutron diffractometers

International Nuclear Information System (INIS)

Adib, M.

2002-01-01

Basic properties and applications of powder neutron Diffractometers are described for optimum use of the continuous neutron beams. These instruments are equipped with position sensitive detectors, neutron guide tubes, and both high intensity and high resolution modes of operation are possible .The principles of both direct and Fourier reverse time-of-flight neutron Diffractometers are also given

Limits of detection in instrumental neutron activation analysis

International Nuclear Information System (INIS)

Guinn, V.P.

1990-01-01

Lower limits of detection (LLODs), frequently referred to simply as limits of detection and abbreviated as LODs, often appear in the literature of analytical chemistry - for numerous different methods of elemental and/or molecular analysis. In this chapter, one particular method of quantitative elemental analysis, that of instrumental neutron activation analysis (INAA), is the subject discussed, with reference to LODs. Particularly in the literature of neutron activation analysis (NAA), many tables of 'interference-free' NAA LODs are available. Not all of these are of much use, because (1) for many the definition used for LOD is not clear, or reasonable, (2) for many, the analysis conditions used are not clearly specified, and (3) for many, the analysis conditions used are specified, but not very practicable for most laboratories. For NAA work, such tables of interference-free LODs are, in any case, only applicable to samples in which, at the time of counting, only one radionuclide is present to any significant extent in the activated sample. It is important to note that tables of INAA LODs, per se, do not exist - since the LOD for a given element, under stated analysis conditions, can vary by orders of magnitude, depending on the elemental composition of the matrix in which it is present. For any given element, its INAA LOD will always be as large as, and usually much larger than, its tabulated 'interference-free' NAA LOD - how much larger depending upon the elemental composition of the matrix in which it is present. As discussed in this chapter, however, an INAA computer program exists that can calculate realistic INAA LODs for any elements of interest, in any kind of specified sample matrix, under any given set of analysis conditions

Neutron capture prompt gamma-ray activation analysis at the NIST cold neutron research facility

Energy Technology Data Exchange (ETDEWEB)

Lindstrom, R M; Zeisler, R; Vincent, D H; Greenberg, R R; Stone, C A; Mackey, E A [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Anderson, D L [Food and Drug Administration, Washington, DC (United States); Clark, D D [Cornell Univ., Ithaca, NY (United States)

1993-01-01

An instrument for neutron capture prompt gamma-ray activation analysis (PGAA) has been constructed as part of the Cold Neutron Research Facility at the 20 MW National Institute of Standards and Technology Research Reactor. The neutron fluence rate (thermal equivalent) is 1.5*10[sup 8] n*cm[sup -2]*s[sup -] [sup 1], with negligible fast neutrons and gamma-rays. With compact geometry and hydrogen-free construction, the sensitivity is sevenfold better than an existing thermal instrument. Hydrogen background is thirtyfold lower. (author) 17 refs.; 2 figs.

Study on neutron irradiation behavior of beryllium as neutron multiplier

Energy Technology Data Exchange (ETDEWEB)

Ishitsuka, Etsuo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

1998-03-01

More than 300 tons beryllium is expected to be used as a neutron multiplier in ITER, and study on the neutron irradiation behavior of beryllium as the neutron multiplier with Japan Materials Testing Reactor (JMTR) were performed to get the engineering data for fusion blanket design. This study started as the study on the tritium behavior in beryllium neutron reflector in order to make clear the generation mechanism on tritium of JMTR primary coolant since 1985. These experiences were handed over to beryllium studies for fusion study, and overall studies such as production technology of beryllium pebbles, irradiation behavior evaluation and reprocessing technology have been started since 1990. In this presentation, study on the neutron irradiation behavior of beryllium as the neutron multiplier with JMTR was reviewed from the point of tritium release, thermal properties, mechanical properties and reprocessing technology. (author)

Spallation neutron source target station issues

International Nuclear Information System (INIS)

Gabriel, T.A.; Barnes, J.N.; Charlton, L.A.

1996-01-01

In many areas of physics, materials and nuclear engineering, it is extremely valuable to have a very intense source of neutrons so that the structure and function of materials can be studied. One facility proposed for this purpose is the National Spallation Neutron Source (NSNS). This facility will consist of two parts: (1) a high-energy (∼1 GeV) and high powered (∼ 1 MW) proton accelerator, and (2) a target station which converts the protons to low-energy (≤ 2 eV) neutrons and delivers them to the neutron scattering instruments. This paper deals with the second part, i.e., the design and development of the NSNS target station and the scientifically challenging issues. Many scientific and technical disciplines are required to produce a successful target station. These include engineering, remote handling, neutronics, materials, thermal hydraulics, and instrumentation. Some of these areas will be discussed

Instrumental neutron activation analysis of human hair and related radiotracer experiments on washing and leaching

International Nuclear Information System (INIS)

Das, H.A.; Hoede, D.; Sloot, H.A. van der; Herber, R.F.M.

1981-11-01

The work done under the IAEA-contract 2440/RB is summarized. The aim was to develop a fast and reliable system for the determination of tracer elements in human head hair by instrumental neutron activation analysis (INAA) and radiotracer washing experiments. The standardized procedure for INAA was applied to hair samples collected by the Coronel Laboratory of the University of Amsterdam. The correlation between trace element contents is considered

Application of instrumental neutron activation analysis and X-ray fluorescence analysis in art pieces investigation

International Nuclear Information System (INIS)

Panczyk, E.; Kierzek, J.; Walis, L.; Ligeza, M.

1996-01-01

The application of instrumental neutron activation analysis have been shown for the trace element identification in dyes of old painting and other art objects. The recognition of their composition is a important measure for attribution. Also the X-ray fluorescence analysis has been frequently used for examination of art objects. The age determination of the old chinese porcelain is a good example described in the paper. 20 refs, 4 figs

Application of instrumental neutron activation analysis for the examination of oil pigments

International Nuclear Information System (INIS)

Chung, Y.S.; Kim, S.H.; Sun, G.M.; Lim, J.M.; Moon, J.H.; Kim, Y.J.; Lim, S.J.; Song, Y.N.; Kim, K.

2011-01-01

This study is to investigate the applicability of instrumental neutron activation analysis (INAA) as a non-destructive examination tool for the quantitative chemical composition analysis associated with authentication, restoration and conservation of art objects in the field of cultural heritage. The quantitative analysis of major, minor and trace elements in Rembrandt's registered oil pigments recently collected at the Korean market as one of the art objects was carried out using INAA facilities of the HANARO research reactor at the Korea Atomic Energy Research Institute in collaboration with the National Museum of Contemporary Art in Korea. Analytical quality control was implemented using NIST SRM 2709, certified reference materials and metal standards. The analytical results for seventeen characteristic elements of thirty-one measured elements were statistically treated to identify the characteristic correlations and patterns between color and source of oil pigment and similarity degree of constituents using a cluster and discriminate analysis. (orig.)

Basics of Neutrons for First Responders

Energy Technology Data Exchange (ETDEWEB)

Rees, Brian G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2018-02-05

These are slides from a presentation on the basics of neutrons. A few topics covered are: common origins of terrestrial neutron radiation, neutron sources, neutron energy, interactions, detecting neutrons, gammas from neutron interactions, neutron signatures in gamma-ray spectra, neutrons and NaI, neutron fluence to dose (msV), instruments' response to neutrons.

Novel tendencies in developing small-angle neutron scattering methods for studying the structure of biological macromolecules

International Nuclear Information System (INIS)

Serdyuk, I.

1995-01-01

In recent 20 years thermal neutron scattering has been acknowledged an important instrument for structural studies in molecular biology. The methods of neutron diffraction of high resolution, which are not discussed in this paper, have already permitted to obtain a detailed representation of the course of proteolytic reactions and have arisen a number of new problems connected with the localization of water molecules and the H-D exchange. The methods of low resolution widely used due to a relative simplicity of the experiment have been successfully applied for both solving structural problems per se and investigating the changes in the structure when macromolecules perform their biological functions. The most promising are novel experimental approaches: the triple isotopic substitution method and the method of spin dynamic polarization. These methods ensure solving structural problems at a higher resolution than the dimensions of the macromolecules studied. Installation of new experimental instruments makes neutron measurements more accessible, and development of direct methods for interpretation of experimental data using the apparatus of spherical harmonics opens new possibilities for small-angle neutron scattering making it a necessary element for interpretation of diffraction data of monocrystals of intricate biological macromolecules. The paper presents a brief account of the tendencies in theoretical development and practical use of small-angle scattering for studying biological macromolecules. Special attention is given to the studies carried out in the Laboratory of Neutron Physics on a unique pulse IBR-2 reactor. (author) 14 refs

Instrumental neutron activation analysis of carbonatites from Homa Mountain, Kenya

International Nuclear Information System (INIS)

Ohde, S.

2004-01-01

Twenty eight (major and trace) elements including eight rare earth elements (REEs) in African carbonatite samples were determined by instrumental neutron activation analysis. The geochemical behavior of trace elements was studied in relation to the order of carbonatite intrusion from C1 to C4 through C2 and C3 at Homa Mountain, Kenya. The enrichment of Mn, Fe, Sr, Ba, Th, U and REE is found in the sixteen carbonatites examined in this study. The general increase in the concentrations of Na, Sc, Mn, Sb, Ba, Th, U and REE occurs from C1 to C4 through C2 and C2c, but C3 carbonatite shows a different pattern. The C3 carbonatite is extraordinarily enriched in Mn, Fe and Ba and is highly enriched in Cr, As, Sb and Th. The chondrite-normalized REE distribution pattern of the C3 carbonatite is not rich in the light REE. Strong fractionation between light and heavy REEs is found in the carbonatites, and moderate fractionation in the two alkalic igneous rock samples. In order to evaluate partitioning of REEs into carbonate, oxide and other mineral fractions, a selective chemical leaching technique on carbonatites was applied and is discussed. (author)

Design of a portable directional neutron source finder

International Nuclear Information System (INIS)

Yamanishi, Hirokuni

2005-01-01

An instrument that determines the direction of a remote existing neutron source has been designed. This instrument combines a polyethylene block and four 3 He counter tubes. The advantages of the instrument are portability and good angular resolution. The count from the detector was varied with the neutron incident angle due to the moderator. Using this characteristic, the direction of the neutron source can be measured precisely by revising the axis of the instrument so that the difference between the four detectors measurements is minimized. Consequently, the direction of the central axis of the instrument in which the response difference of the four detectors reaches a minimum indicates the direction of the neutron source. The practical use of the instrument was demonstrated by 252 Cf source irradiation experiment and MCNP simulation

Elementary composition of the siderurgy slag by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Oliveira, Helder de; Piau, Wilson Caixeta; Mortatti, Jefferson; Sarries, Gabriel Adrian

2000-01-01

The slag has been applied to the ground to neutralize its acidity, in similar way to the calcareous rock, contributing in the agriculture as corrective of the acidity alone it and source of nutrients for the plants. However, the alternative for the agricultural slag exploitation is related to metal texts heavy gifts in the slag. The objective of the present work was to survey of the chemical composition of trashes generated in blast high-oven, steel, oven of pan and fertilizers that had used in its manufacture slag of siderurgy for the technique of instrumental neutron activation analysis. The results had evidenced the existence of high variations in the elements Ce, Cr, In, K, Sb and Zn in the distinct analyzed samples. (author)

Use of cold neutrons for condensed matter research at the neutron guide laboratory ELLA in Juelich

International Nuclear Information System (INIS)

Schaetzler, R.; Monkenbusch, M.

1998-01-01

Cold neutrons produced in the FRJ-2 DIDO reactor are guided into the external hall ELLA. It hosts 10 instruments that are red by three major neutron guides. Cold neutrons allow for diffraction and small angle scattering experiments resolving mesoscopic structures (1 to 100 nm). Contrast variation by isotopic substitution in chemically identical species yields information uniquely accessible bi neutrons. Inelastic scattering of cold neutrons allows investigating slow molecular motions because the low neutron velocity results in large relative velocity changes even at small energy transfers. The SANS machines and the HADAS reflectometer serve as structure probes and the backscattering BSS1 and spin-echo spectrometers NSE as main dynamics probes. Besides this the diffuse scattering instrument DNS and the lattice parameter determination instrument LAP deal mainly with crystals and their defects. Finally the beta-NMR and the EKN position allow for methods other than scattering employing nuclear reactions for solid state physics, chemistry and biology/medicine. (author)

Determination of As by instrumental neutron activation analysis in sectioned hair samples for forensic purposes: chronic or acute poisoning?

Czech Academy of Sciences Publication Activity Database

Kučera, Jan; Kofronova, K.

2011-01-01

Roč. 287, č. 3 (2011), s. 769-772 ISSN 0236-5731 Institutional research plan: CEZ:AV0Z10480505 Keywords : Instrumental neutron activation analysis * Hair * Arsenic poisoning Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.520, year: 2011

Application of instrumental neutron activation and X-ray fluorescence analysis to the examination of objects of art

Science.gov (United States)

Panczyk, E.; Ligeza, M.; Walis, L.

1999-01-01

In the Institute of Nuclear Chemistry and Technology in Warsaw in collaboration with the Department of Preservation and Restoration of Works of Art of the Academy of Fine Arts in Cracow and National Museum in Warsaw systematic studies using nuclear methods, particulary instrumental neutron activation analysis and X-ray fluorescence analysis, have been carried out on the panel paintings from the Krakowska- Nowosadecka School and Silesian School of the period from the XIV-XVII century, Chinese and Thai porcelains and mummies fillings of Egyptian sarcophagi. These studies will provide new data to the existing data base, will permit to compare materials used by various schools and individual artists.

Application of instrumental neutron activation and X-ray fluorescence analysis to the examination of objects of art

International Nuclear Information System (INIS)

Panczyk, E.; Ligeza, M.; Walis, L.

1999-01-01

In the Institute of Nuclear Chemistry and Technology in Warsaw in collaboration with the Department of Preservation and Restoration of Works of Art of the Academy of Fine Arts in Cracow and National Museum in Warsaw systematic studies using nuclear methods, particularly instrumental neutron activation analysis and X-ray fluorescence analysis, have been carried out on the panel paintings from the Krakowska-Nowosadecka School and Silesian School of the period from the XIV-XVII century, Chinese and Thai porcelains and mummies fillings of Egyptian sarcophagi. These studies will provide new data to the existing data base, will permit to compare materials used by various schools and individual artists. (author)

Chemical compositions of magnetic, stony spherules from deep-sea sediments determined by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Yamakoshi, Kazuo

1984-01-01

Chemical compositions of magnetic, stony spherules from deep sea sediments were determined by instrumental neutron activation analysis. High Ir, Au, Ni and Co contents indicate their extraterrestrial origin. The obtained compositions are considerably different from those of chondrites. It can be qualitatively interpreted, however, that cosmic matters having the compositions of chondrites are changed into magnetic, stony spherules by thermal degenerations during their atmospheric entry. (author)

The multiple disk chopper neutron time-of-flight spectrometer at NIST

International Nuclear Information System (INIS)

Altorfer, F.B.; Cook, J.C.; Copley, J.R.D.

1995-01-01

A highly versatile multiple disk chopper neutron time-of-flight spectrometer is being installed at the Cold Neutron Research Facility of the National institute of Standards and Technology. This new instrument will fill an important gap in the portfolio of neutron inelastic scattering spectrometers in North America. It will be used for a wide variety of experiments such as studies of magnetic and vibrational excitations, tunneling spectroscopy, and quasielastic neutron scattering investigations of local and translational diffusion. The instrument uses disk choppers to monochromate and pulse the incident beam, and the energy changes of scattered neutrons are determined from their times-of-flight to a large array of detectors. The disks and the guide have been designed to make the instrument readily adaptable to the specific performance requirements of experimenters. The authors present important aspects of the design, as well as estimated values of the flux at the sample and the energy resolution for elastic scattering. The instrument should be operational in 1996

Oesophageal cancer in the Transkei. Determination of trace element concentrations in selected plant material by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Renan, M.J.; Drennan, B.D.; Keddy, R.J.; Sellschop, J.P.F.

1979-01-01

The results of the analysis by instrumental neutron activation for the concentration of trace elements in plant materials from certain areas in the Transkei region of southern Africa are presented. These areas are selected for their characteristic high or low incidence of carcinoma of the oesophagus. To broaden the suite of elements for which analysed and to overcome some of the limitations of neutron activation analysis, certain other nuclear analyses and methods are suggested which, if utilized, would increase the number of elements determined, and so improve the information available. (author)

Small-angle neutron scattering instrument of Institute for Solid State Physics, the Univeristy of Tokyo (SANS-U) and its application to biology

Energy Technology Data Exchange (ETDEWEB)

Ito, Yuji; Imai, Masayuki; Takahashi, Shiro [Univ. of Tokyo, Tokai Naka Ibaraki (Japan)

1994-12-31

A small-angle neutron spectrometer (SANS-U) suitable for the study of mesoscopic structure in the field of polymer chemistry and biology, has been constructed at the guide hall of JRR-3M reactor at the Japan Atomic Energy Research Institute. The instrument is 32m long and utilizes a mechanical velocity selector and pinhole collimation to provide a continuous beam with variable wavelength in the range from 5 to 10{Angstrom}. The neutron detector is a 65 x 65cm{sup 2} 2D position sensitive proportional counter. The practical Q range of SANS-U is 0.0008 to 0.45{Angstrom}{sup -1}. The design, characteristics and performance of SANS-U are described with some biological studies using SANS-U.

New Techniques in Neutron Scattering

DEFF Research Database (Denmark)

Birk, Jonas Okkels

potential performance than any existing facility, however in order to use this pulse structure optimally many existing neutron scattering instruments will need to be redesigned. This defense will concentrate on the design and optimization of the inverse time-of-flight cold neutron spectrometer CAMEA......, simulations and prototyping to optimize the instrument and ensure that it will deliver the predicted performance when constructed. During the design a new prismatic analyser concept that can be of interest to many other neutron spectrometers was developed. The design work was compiled into an instrument......Neutron scattering is an important experimental technique in amongst others solid state physics, biophysics, and engineering. This year construction of European Spallation Source (ESS) was commenced in Lund, Sweeden. The facility will use a new long pulsed source principle to obtain higher...

GINA--a polarized neutron reflectometer at the Budapest Neutron Centre.

Science.gov (United States)

Bottyán, L; Merkel, D G; Nagy, B; Füzi, J; Sajti, Sz; Deák, L; Endrőczi, G; Petrenko, A V; Major, J

2013-01-01

The setup, capabilities, and operation parameters of the neutron reflectometer GINA, the recently installed "Grazing Incidence Neutron Apparatus" at the Budapest Neutron Centre, are introduced. GINA, a dance-floor-type, constant-energy, angle-dispersive reflectometer is equipped with a 2D position-sensitive detector to study specular and off-specular scattering. Wavelength options between 3.2 and 5.7 Å are available for unpolarized and polarized neutrons. Spin polarization and analysis are achieved by magnetized transmission supermirrors and radio-frequency adiabatic spin flippers. As a result of vertical focusing by a five-element pyrolytic graphite monochromator, the reflected intensity from a 20 × 20 mm(2) sample has been doubled. GINA is dedicated to studies of magnetic films and heterostructures, but unpolarized options for non-magnetic films, membranes, and other surfaces are also provided. Shortly after its startup, reflectivity values as low as 3 × 10(-5) have been measured by the instrument. The instrument capabilities are demonstrated by a non-polarized and a polarized reflectivity experiment on a Si wafer and on a magnetic film of [(62)Ni/(nat)Ni](5) isotope-periodic layer composition. The facility is now open for the international user community. Its further development is underway establishing new sample environment options and spin analysis of off-specularly scattered radiation as well as further decreasing the background.

GINA-A polarized neutron reflectometer at the Budapest Neutron Centre

Energy Technology Data Exchange (ETDEWEB)

Bottyan, L.; Merkel, D. G.; Nagy, B.; Sajti, Sz.; Deak, L.; Endroczi, G. [Wigner RCP, RMKI, H-1525 Budapest, P.O. Box 49 (Hungary); Fuezi, J. [Wigner RCP, SZFKI, H-1525 Budapest, P.O. Box 49 (Hungary); University of Pecs, Pollack Mihaly Faculty of Engineering and Information Technology, H-7602 Pecs, P.O. Box 219 (Hungary); Petrenko, A. V. [Frank Laboratory of Neutron Physics, JINR, Joliot-Curie 6, Dubna, 141980 (Russian Federation); Major, J. [Wigner RCP, RMKI, H-1525 Budapest, P.O. Box 49 (Hungary); Max-Planck-Institut fuer Intelligente Systeme (formerly Max-Planck-Institut fuer Metallforschung), Heisenbergstr. 3, D-70569 Stuttgart (Germany)

2013-01-15

The setup, capabilities, and operation parameters of the neutron reflectometer GINA, the recently installed 'Grazing Incidence Neutron Apparatus' at the Budapest Neutron Centre, are introduced. GINA, a dance-floor-type, constant-energy, angle-dispersive reflectometer is equipped with a 2D position-sensitive detector to study specular and off-specular scattering. Wavelength options between 3.2 and 5.7 A are available for unpolarized and polarized neutrons. Spin polarization and analysis are achieved by magnetized transmission supermirrors and radio-frequency adiabatic spin flippers. As a result of vertical focusing by a five-element pyrolytic graphite monochromator, the reflected intensity from a 20 Multiplication-Sign 20 mm{sup 2} sample has been doubled. GINA is dedicated to studies of magnetic films and heterostructures, but unpolarized options for non-magnetic films, membranes, and other surfaces are also provided. Shortly after its startup, reflectivity values as low as 3 Multiplication-Sign 10{sup -5} have been measured by the instrument. The instrument capabilities are demonstrated by a non-polarized and a polarized reflectivity experiment on a Si wafer and on a magnetic film of [{sup 62}Ni/{sup nat}Ni]{sub 5} isotope-periodic layer composition. The facility is now open for the international user community. Its further development is underway establishing new sample environment options and spin analysis of off-specularly scattered radiation as well as further decreasing the background.

Neutron-scattering study of low-energy excitations in triphenyl phosphite

CERN Document Server

Mayer, J; Massalska-Arodz, M; Janik, J A; Natkaniec, I; Steinsvoll, O

2002-01-01

The low-energy excitations in crystalline and glassy triphenyl phosphite were studied by inelastic incoherent neutron scattering with two different instruments. The results - the incoherent dynamic structure factor S(2 theta,omega) and the density of states G(omega) - were obtained using direct and inverted geometry time-of-flight spectrometers, respectively. The probable origin of the excess density of states in the glass (boson peak) is discussed. (orig.)

Neutron-scattering study of low-energy excitations in triphenyl phosphite

International Nuclear Information System (INIS)

Mayer, J.; Krawczyk, J.; Massalska-Arodz, M.; Janik, J.A.; Natkaniec, I.; Steinsvoll, O.

2002-01-01

The low-energy excitations in crystalline and glassy triphenyl phosphite were studied by inelastic incoherent neutron scattering with two different instruments. The results - the incoherent dynamic structure factor S(2θ,ω) and the density of states G(ω) - were obtained using direct and inverted geometry time-of-flight spectrometers, respectively. The probable origin of the excess density of states in the glass (boson peak) is discussed. (orig.)

Rare earths analysis of rock samples by instrumental neutron activation analysis, internal standard method

International Nuclear Information System (INIS)

Silachyov, I.

2016-01-01

The application of instrumental neutron activation analysis for the determination of long-lived rare earth elements (REE) in rock samples is considered in this work. Two different methods are statistically compared: the well established external standard method carried out using standard reference materials, and the internal standard method (ISM), using Fe, determined through X-ray fluorescence analysis, as an element-comparator. The ISM proved to be the more precise method for a wide range of REE contents and can be recommended for routine practice. (author)

Experimental design technique applied to the validation of an instrumental Neutron Activation Analysis procedure

International Nuclear Information System (INIS)

Santos, Uanda Paula de M. dos; Moreira, Edson Gonçalves

2017-01-01

In this study optimization of procedures and standardization of Instrumental Neutron Activation Analysis (INAA) method were carried out for the determination of the elements bromine, chlorine, magnesium, manganese, potassium, sodium and vanadium in biological matrix materials using short irradiations at a pneumatic system. 2 k experimental designs were applied for evaluation of the individual contribution of selected variables of the analytical procedure in the final mass fraction result. The chosen experimental designs were the 2 3 and the 2 4 , depending on the radionuclide half life. Different certified reference materials and multi-element comparators were analyzed considering the following variables: sample decay time, irradiation time, counting time and sample distance to detector. Comparator concentration, sample mass and irradiation time were maintained constant in this procedure. By means of the statistical analysis and theoretical and experimental considerations, it was determined the optimized experimental conditions for the analytical methods that will be adopted for the validation procedure of INAA methods in the Neutron Activation Analysis Laboratory (LAN) of the Research Reactor Center (CRPq) at the Nuclear and Energy Research Institute (IPEN /CNEN-SP). Optimized conditions were estimated based on the results of z-score tests, main effect, interaction effects and better irradiation conditions. (author)

Experimental design technique applied to the validation of an instrumental Neutron Activation Analysis procedure

Energy Technology Data Exchange (ETDEWEB)

Santos, Uanda Paula de M. dos; Moreira, Edson Gonçalves, E-mail: uandapaula@gmail.com, E-mail: emoreira@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

2017-07-01

In this study optimization of procedures and standardization of Instrumental Neutron Activation Analysis (INAA) method were carried out for the determination of the elements bromine, chlorine, magnesium, manganese, potassium, sodium and vanadium in biological matrix materials using short irradiations at a pneumatic system. 2{sup k} experimental designs were applied for evaluation of the individual contribution of selected variables of the analytical procedure in the final mass fraction result. The chosen experimental designs were the 2{sup 3} and the 2{sup 4}, depending on the radionuclide half life. Different certified reference materials and multi-element comparators were analyzed considering the following variables: sample decay time, irradiation time, counting time and sample distance to detector. Comparator concentration, sample mass and irradiation time were maintained constant in this procedure. By means of the statistical analysis and theoretical and experimental considerations, it was determined the optimized experimental conditions for the analytical methods that will be adopted for the validation procedure of INAA methods in the Neutron Activation Analysis Laboratory (LAN) of the Research Reactor Center (CRPq) at the Nuclear and Energy Research Institute (IPEN /CNEN-SP). Optimized conditions were estimated based on the results of z-score tests, main effect, interaction effects and better irradiation conditions. (author)

A preliminary study of archaeological ceramic from the Sao Paulo II, Brazil, archaeological site by Instrumental Neutron Activation Analysis (INAA)

International Nuclear Information System (INIS)

Ribeiro, Rogerio B.; Munita, Casimiro S.; Oliveira, Paulo M.S.; Neves, Eduardo G.; Tamahara, Eduardo K.

2011-01-01

The determination of trace elements plays an important role in the characterization of archaeological ceramics. It is well established that ceramics can be grouped based on similarities/dissimilarities derived from chemical data. Different analytical methods can be applied to determine the sample composition. Instrumental neutron activation analysis (INAA) is the method preferred because present several advantages in relation to the other techniques. In this work, the elements determined were As, K, La, Lu, Na, Nd, Sb, Sm, U, Yb, Ba, Ce, Co, Cr, Cs, I, Fe, Hf, Rb, Sc, Ta , Tb, Th and Zn to carry out a preliminary chemical characterization in 44 ceramic samples from Sao Paulo II archaeological site by INAA. The site is located in Coari city, 363 km from Manaus, Amazonas state (AM). The elementary concentration results were studied using multivariate statistical methods. The similarity/dissimilarity among the samples was studied by means of discriminant analysis. The compositions group classification was done through cluster analysis, showing the formation of the three distinct groups of the ceramics. (author)

Study on the mineral extraction of legume and grass species from various soil types, by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Piasentin, R.M.; Armelin, M.J.A.; Cruvinel, P.E.

1998-01-01

Instrumental neutron activation analysis (INAA), followed by gamma-ray spectrometry, was used to determine the concentration of K, Ca, Mg, Na, Zn, Fe, Mn, Mo, Co, Cr, La, Eu and Th in six species of legumes and three species of grasses. Each species of forage was cultivated on two different oxisols, that is, a red yellow Latossol and a dark red Latossol, with the aim of comparing the influence of the soils in the mineral extraction. Besides, on each kind of soil, two different limestone concentrations were used in order to verify how the soil pH correction could influence the elemental absorption in each species, and at the same time; to search for an optimum value of limestone concentration for each soil. (author)

Application of instrumental neutron activation analysis for the examination of oil pigments

Energy Technology Data Exchange (ETDEWEB)

Chung, Y.S.; Kim, S.H.; Sun, G.M.; Lim, J.M.; Moon, J.H.; Kim, Y.J. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lim, S.J.; Song, Y.N.; Kim, K. [National Museum of Contemporary Art, Gwacheon, Gyeonggi-do (Korea, Republic of)

2011-07-01

This study is to investigate the applicability of instrumental neutron activation analysis (INAA) as a non-destructive examination tool for the quantitative chemical composition analysis associated with authentication, restoration and conservation of art objects in the field of cultural heritage. The quantitative analysis of major, minor and trace elements in Rembrandt's {sup registered} oil pigments recently collected at the Korean market as one of the art objects was carried out using INAA facilities of the HANARO research reactor at the Korea Atomic Energy Research Institute in collaboration with the National Museum of Contemporary Art in Korea. Analytical quality control was implemented using NIST SRM 2709, certified reference materials and metal standards. The analytical results for seventeen characteristic elements of thirty-one measured elements were statistically treated to identify the characteristic correlations and patterns between color and source of oil pigment and similarity degree of constituents using a cluster and discriminate analysis. (orig.)

Trace elements in California aerosols. Part I. Instrumental neutron activation analysis techniques

International Nuclear Information System (INIS)

Ragaini, R.C.; Ralston, H.R.; Garvis, D.; Kaifer, R.

1975-01-01

Instrumental Neutron Activation Analysis (INAA) done at LLL played a key role in the 1972--1974 California Aerosol Characterization Experiment (ACHEX), a major experiment in the chemistry of aerosols in urban and non-urban sites of California sponsored by the State of California Air Resources Board. The main purpose of INAA was to measure the particle size distributions and diurnal patterns of key chemical constituents in aerosols collected in California. These data were used to satisfy some of the key objectives of ACHEX, including aerosol characterization and evaluation of the origins and evolutions of aerosols. Secondary uses of INAA were the validations of the Lundgren rotating drum cascade impactors used in the ACHEX, and validations of other analytical techniques used in the chemical analyses. As a result of these studies, it was concluded that techniques using INAA were useful operational methods for chemical analysis of aerosols collected over two-hour periods in urban air with an active monitoring program. (U.S.)

Determination of Li, B, and F by rapid instrumental neutron activation analysis using beta-particle counting

International Nuclear Information System (INIS)

Schmidt, J.O.; Palgaard, L.; Gwozdz, R.; Belhage, L.O.

1984-01-01

For the simultaneous determination of Li, B, and F, the application of rapid instrument neutron activation analysis was studied using 1.5s of irradiation and β-particle counting of 8 Li, 12 B, and 20 F. The fast transfer facility, Mach-1, the counting equipment, a 4-channel multiplexer, and a time-base controller are discussed. Further, the technique of simultaneous decay curve analysis of three successive decays is presented and quality control by residual analysis is demonstrated. Finally, analytical results are presented of the NBS-environmental standards Coal-1632a and Coal-1635, and of three BCR-coals intended as references materials

A study on the measurement and evaluation of neutron flux using SPNDs during nuclear fuel irradiation test

Energy Technology Data Exchange (ETDEWEB)

Son, J. M.; Kim, B. K.; Oh, J. M.; Park, S. J.; Lee, B. H.; Seo, C. G.; Kang, Y. H. [KAERI, Taejon (Korea, Republic of)

2003-10-01

As a part of the development of instrumentation technologies for a nuclear fuel irradiation test in HANARO(High-Flux Advanced Nuclear Application Reactor), a study is performed to measure and evaluate the neutron flux at the same position as the nuclear fuel during irradiation test using the SPND(Self Powered Neutron Detector). To perform this study, rhodium type SPNDs and amplifier are selected suitable to irradiation test, and the selected SPNDs are installed in instrumented fuel capsule(02F-11K). The irradiation test using a instrumented fuel capsule are performed in the OR5 vertical hole of HANARO for about 54 days, and SPND output signals are acquired successfully during irradiation test. Acquired SPND signals are analyzed and evaluated as a reliable data by COSMOS Code, and this will be utilized for the fuel related research together with fuel center temperature and reactor operation data.

HYSPEC : A CRYSTAL TIME OF FLIGHT HYBRID SPECTROMETER FOR THE SPALLATION NEUTRON SOURCE

International Nuclear Information System (INIS)

SHAPIRO, S.M.; ZALIZNYAK, I.A.

2002-01-01

This document lays out a proposal by the Instrument Development Team (IDT) composed of scientists from leading Universities and National Laboratories to design and build a conceptually new high-flux inelastic neutron spectrometer at the pulsed Spallation Neutron Source (SNS) at Oak Ridge. This instrument is intended to supply users of the SNS and scientific community, of which the IDT is an integral part, with a platform for ground-breaking investigations of the low-energy atomic-scale dynamical properties of crystalline solids. It is also planned that the proposed instrument will be equipped with a polarization analysis capability, therefore becoming the first polarized beam inelastic spectrometer in the SNS instrument suite, and the first successful polarized beam inelastic instrument at a pulsed spallation source worldwide. The proposed instrument is designed primarily for inelastic and elastic neutron spectroscopy of single crystals. In fact, the most informative neutron scattering studies of the dynamical properties of solids nearly always require single crystal samples, and they are almost invariably flux-limited. In addition, in measurements with polarization analysis the available flux is reduced through selection of the particular neutron polarization, which puts even more stringent limits on the feasibility of a particular experiment. To date, these investigations have mostly been carried out on crystal spectrometers at high-flux reactors, which usually employ focusing Bragg optics to concentrate the neutron beam on a typically small sample. Construction at Oak Ridge of the high-luminosity spallation neutron source, which will provide intense pulsed neutron beams with time-averaged fluxes equal to those at medium-flux reactors, opens entirely new opportunities for single crystal neutron spectroscopy. Drawing upon experience acquired during decades of studies with both crystal and time-of-flight (TOF) spectrometers, the IDT has developed a conceptual

HYSPEC : A CRYSTAL TIME OF FLIGHT HYBRID SPECTROMETER FOR THE SPALLATION NEUTRON SOURCE.

Energy Technology Data Exchange (ETDEWEB)

SHAPIRO,S.M.; ZALIZNYAK,I.A.

2002-12-30

This document lays out a proposal by the Instrument Development Team (IDT) composed of scientists from leading Universities and National Laboratories to design and build a conceptually new high-flux inelastic neutron spectrometer at the pulsed Spallation Neutron Source (SNS) at Oak Ridge. This instrument is intended to supply users of the SNS and scientific community, of which the IDT is an integral part, with a platform for ground-breaking investigations of the low-energy atomic-scale dynamical properties of crystalline solids. It is also planned that the proposed instrument will be equipped with a polarization analysis capability, therefore becoming the first polarized beam inelastic spectrometer in the SNS instrument suite, and the first successful polarized beam inelastic instrument at a pulsed spallation source worldwide. The proposed instrument is designed primarily for inelastic and elastic neutron spectroscopy of single crystals. In fact, the most informative neutron scattering studies of the dynamical properties of solids nearly always require single crystal samples, and they are almost invariably flux-limited. In addition, in measurements with polarization analysis the available flux is reduced through selection of the particular neutron polarization, which puts even more stringent limits on the feasibility of a particular experiment. To date, these investigations have mostly been carried out on crystal spectrometers at high-flux reactors, which usually employ focusing Bragg optics to concentrate the neutron beam on a typically small sample. Construction at Oak Ridge of the high-luminosity spallation neutron source, which will provide intense pulsed neutron beams with time-averaged fluxes equal to those at medium-flux reactors, opens entirely new opportunities for single crystal neutron spectroscopy. Drawing upon experience acquired during decades of studies with both crystal and time-of-flight (TOF) spectrometers, the IDT has developed a conceptual

Neutron reflectometry

DEFF Research Database (Denmark)

Klösgen-Buchkremer, Beate Maria

2014-01-01

of desired information. In the course, an introduction into the method and an overview on selected instruments at large scale facilities will be presented. Examples will be given that illustrate the potential of the method, mostly based on organic films. Results from the investigation of layered films......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...... films or films with magnetic properties. The reason is the peculiar property of neutron light since the mass of a neutron is close to the one of a proton, and since it bears a magnetic moment. The optical properties of matter, when interacting with neutrons, are described by a refractive index...

J-PARC and the prospective neutron sciences

International Nuclear Information System (INIS)

Masatoshi Arai

2009-01-01

Full text: J-PARC is an interdisciplinary facility with high power proton accelerator complex containing particle physics, nuclear physics, muon science and neutron science facilities. After 8 years construction, she is almost ready to open for users. Materials-Life Science Facility (MLF) of J-PARC is composed from very intensive pulsed neutron and muon facilities at 1 MW of the accelerated proton power. The neutron peak flux will be as high as several hundred times of existing high flux reactors. Therefore, it is highly expected that new sciences will be explored by J-PARC, MLF. The first neutrons was already produced in the last May. The MLF facility has 23 neutron beam ports. About 12 instruments are under commissioning or construction. Out of four instruments are already opened for users since December, 2008.. In the commissioning High Resolution Powder Diffractometer showed the world highest resolution d/d=0.04% as was designed. Other instruments, high intensity powder diffractometer, protein crystal diffractometer, residual stress analysis diffractometer, high intensity chopper spectrometer, confirmed expected intensity and spectrum from neutron beam line. By the end of March, a cold neutron chopper spectrometer will also come on line. Those instruments are taking advantages with optical devices for neutron transport to realize very high flux at sample position. By taking high performances of neutron moderators of MLF, the instruments will realize the world class resolution and high intensity. Ranging from Bio-science, material science, engineering, industrial use of neutrons to fundamental physics, we are exciting to see cutting-edge sciences with great anticipation to be produced from J-PARC, MLF. (author)

Analysis of medicinal plants and soil sample from Haridwar region by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Maharia, R.S.; Dutta, R.K.; Acharya, R.; Reddy, A.V.R.

2009-01-01

Samples of leaves and stems of four medicinal plants namely Kalmegh, Amaltas, Moalshri, and Arusa were analysed by Instrumental Neutron Activation Analysis. Soil from same location was analyzed. Though concentrations of many elements were determined in the plant samples, results of selected elements namely Na, K, Mn, Fe, Co, Cr, Zn and As are discussed in this paper. The results show that all medicinal plants analyzed have lower elemental contents except Zn compared to the soil. (author)

The Phase-Space Transformer Instrument (PASTIS) and the Phase-Space Transformation on Ultra-Cold Neutrons

International Nuclear Information System (INIS)

Henggeler, W.; Boehm, M.

2003-11-01

Both reports - part I by Wolfgang Henggeler and part II by Martin Boehm - serve as a comprehensive basis for the realisation of a PST (phase-space transformation) instrument coupled either to cold or ultra-cold neutrons, respectively. This publication accidentally coincides with the 200 th birthday of the Austrian physicist C.A. Doppler who discovered the principle (i.e., the effect denoted later by his name) giving rise to the phase-space transformation described in the present work. (author)

Single-crystal neutron diffraction studies of hydrogen-bonded systems: Two recent examples from IPNS

Energy Technology Data Exchange (ETDEWEB)

Koetzle, Thomas F. [IPNS Division, Argonne National Laboratory, Argonne, IL 60439 (United States)], E-mail: tkoetzle@anl.gov; Piccoli, Paula M.B.; Schultz, Arthur J. [IPNS Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

2009-02-21

Beginning with work in the 1950s at the first generation of research reactors, studies of hydrogen-bonded systems have been a prime application for single-crystal neutron diffraction. The range of systems studied was extended in the 1960s and 1970s, with the advent of high flux reactor sources, and beginning around 1980 studies at pulsed neutron sources have made increasingly important contributions. Recently at the Argonne Intense Pulsed Neutron Source (IPNS), working with collaborators, we completed two studies of hydrogen-bonded systems that will serve to illustrate topics of current interest. In the first study, on andrographolide, an active diterpenoid natural product, our neutron diffraction results definitively characterize the hydrogen-bonding interactions. The second IPNS study is on tetraacetylethane (TAE), a {beta}-diketone enol system with a very short, strong intramolecular O-H...O hydrogen bond. At IPNS, we have determined the neutron crystal structure of TAE at five temperatures between 20 and 298 K to investigate changes in the structure with temperature and to probe for disorder. Despite the successes illustrated by the two examples presented here and by many other studies, at present applications of single-crystal neutron diffraction continue to be extremely flux limited and constrained by the requirement for mm-size crystals for many problems. These limitations are being addressed through the realization of powerful instruments at a new generation of pulsed neutron sources, including in the USA the TOPAZ and MaNDi single-crystal diffractometers that are under development at the Spallation Neutron Source (SNS)

Single-crystal neutron diffraction studies of hydrogen-bonded systems: Two recent examples from IPNS

Science.gov (United States)

Koetzle, Thomas F.; Piccoli, Paula M. B.; Schultz, Arthur J.

2009-02-01

Beginning with work in the 1950s at the first generation of research reactors, studies of hydrogen-bonded systems have been a prime application for single-crystal neutron diffraction. The range of systems studied was extended in the 1960s and 1970s, with the advent of high flux reactor sources, and beginning around 1980 studies at pulsed neutron sources have made increasingly important contributions. Recently at the Argonne Intense Pulsed Neutron Source (IPNS), working with collaborators, we completed two studies of hydrogen-bonded systems that will serve to illustrate topics of current interest. In the first study, on andrographolide, an active diterpenoid natural product, our neutron diffraction results definitively characterize the hydrogen-bonding interactions. The second IPNS study is on tetraacetylethane (TAE), a β-diketone enol system with a very short, strong intramolecular O-H⋯O hydrogen bond. At IPNS, we have determined the neutron crystal structure of TAE at five temperatures between 20 and 298 K to investigate changes in the structure with temperature and to probe for disorder. Despite the successes illustrated by the two examples presented here and by many other studies, at present applications of single-crystal neutron diffraction continue to be extremely flux limited and constrained by the requirement for mm-size crystals for many problems. These limitations are being addressed through the realization of powerful instruments at a new generation of pulsed neutron sources, including in the USA the TOPAZ and MaNDi single-crystal diffractometers that are under development at the Spallation Neutron Source (SNS).

Single-crystal neutron diffraction studies of hydrogen-bonded systems: Two recent examples from IPNS

International Nuclear Information System (INIS)

Koetzle, Thomas F.; Piccoli, Paula M.B.; Schultz, Arthur J.

2009-01-01

Beginning with work in the 1950s at the first generation of research reactors, studies of hydrogen-bonded systems have been a prime application for single-crystal neutron diffraction. The range of systems studied was extended in the 1960s and 1970s, with the advent of high flux reactor sources, and beginning around 1980 studies at pulsed neutron sources have made increasingly important contributions. Recently at the Argonne Intense Pulsed Neutron Source (IPNS), working with collaborators, we completed two studies of hydrogen-bonded systems that will serve to illustrate topics of current interest. In the first study, on andrographolide, an active diterpenoid natural product, our neutron diffraction results definitively characterize the hydrogen-bonding interactions. The second IPNS study is on tetraacetylethane (TAE), a β-diketone enol system with a very short, strong intramolecular O-H...O hydrogen bond. At IPNS, we have determined the neutron crystal structure of TAE at five temperatures between 20 and 298 K to investigate changes in the structure with temperature and to probe for disorder. Despite the successes illustrated by the two examples presented here and by many other studies, at present applications of single-crystal neutron diffraction continue to be extremely flux limited and constrained by the requirement for mm-size crystals for many problems. These limitations are being addressed through the realization of powerful instruments at a new generation of pulsed neutron sources, including in the USA the TOPAZ and MaNDi single-crystal diffractometers that are under development at the Spallation Neutron Source (SNS).

Chemical study of sediments from Solimoes and Negro rivers by Instrumental Neutron Activation Analysis (INAA)

Energy Technology Data Exchange (ETDEWEB)

Santos, Jose O. dos [Coordenacao de Cursos Tecnicos e Superiores. Instituto Federal de Educacao, Ciencia e Tecnologia de Sergipe, Lagarto, SE (Brazil); Munita, Casimiro S., E-mail: camunita@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Soares, Emilio A.A., E-mail: easores@ufam.edu.br [Departamento de Geociencias. Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil)

2011-07-01

The events of the last 70,000 yrs of the history of the Solimoes-Amazon river system are recorded in the fluvial terraces at region of confluence of the Negro and Solimoes rivers, and are markers of changes in the landscape of the Amazon region and it can be observed by analyzing the sedimentary deposits quaternary in Amazon fluvial system. The aim of this work was to contribute with the characterization sedimentological - stratigraphic of Pleistocene succession of the confluence zone of the Negro and Solimoes rivers by means of elemental chemical analysis. To provenance study, 24 elements were determined by Instrumental Neutron Activation Analysis from sediment samples collected at confluence of Negro and Solimoes rivers and the results were interpreted using cluster and linear discriminant analysis, which classification to priori were samples previously defined according to Pleistocene stratigraphic units individualized at study area. According to discriminant analysis, one can infer that samples from the basin of the Solimoes River and Parana do Ariau grabens (GPA) are not significantly different, but there was a clear separation of sediments from Negro and GPA groups. It was also obtained that samples from highest and lowest terraces that the of the Solimoes river and Parana do Ariau are different, suggesting that it is a process that reflects the influence of chemical weathering on the uppermost terrace deposits. Thus, this work contributes to determine the contribution of the sediments deposited by the Solimoes and Negro rivers in the filling of tectonic depressions and in the variations of degree of weathering between younger and older units, and provides additional subsidies to build the geological evolution of the area. (author)

Chemical study of sediments from Solimoes and Negro rivers by Instrumental Neutron Activation Analysis (INAA)

International Nuclear Information System (INIS)

Santos, Jose O. dos; Munita, Casimiro S.; Soares, Emilio A.A.

2011-01-01

The events of the last 70,000 yrs of the history of the Solimoes-Amazon river system are recorded in the fluvial terraces at region of confluence of the Negro and Solimoes rivers, and are markers of changes in the landscape of the Amazon region and it can be observed by analyzing the sedimentary deposits quaternary in Amazon fluvial system. The aim of this work was to contribute with the characterization sedimentological - stratigraphic of Pleistocene succession of the confluence zone of the Negro and Solimoes rivers by means of elemental chemical analysis. To provenance study, 24 elements were determined by Instrumental Neutron Activation Analysis from sediment samples collected at confluence of Negro and Solimoes rivers and the results were interpreted using cluster and linear discriminant analysis, which classification to priori were samples previously defined according to Pleistocene stratigraphic units individualized at study area. According to discriminant analysis, one can infer that samples from the basin of the Solimoes River and Parana do Ariau grabens (GPA) are not significantly different, but there was a clear separation of sediments from Negro and GPA groups. It was also obtained that samples from highest and lowest terraces that the of the Solimoes river and Parana do Ariau are different, suggesting that it is a process that reflects the influence of chemical weathering on the uppermost terrace deposits. Thus, this work contributes to determine the contribution of the sediments deposited by the Solimoes and Negro rivers in the filling of tectonic depressions and in the variations of degree of weathering between younger and older units, and provides additional subsidies to build the geological evolution of the area. (author)

Neutron-multiplication measurement instrument

Energy Technology Data Exchange (ETDEWEB)

Nixon, K.V.; Dowdy, E.J.; France, S.W.; Millegan, D.R.; Robba, A.A.

1982-01-01

The Advanced Nuclear Technology Group of the Los Alamos National Laboratory is now using intelligent data-acquisition and analysis instrumentation for determining the multiplication of nuclear material. Earlier instrumentation, such as the large NIM-crate systems, depended on house power and required additional computation to determine multiplication or to estimate error. The portable, battery-powered multiplication measurement unit, with advanced computational power, acquires data, calculates multiplication, and completes error analysis automatically. Thus, the multiplication is determined easily and an available error estimate enables the user to judge the significance of results.

Neutron multiplication measurement instrument

International Nuclear Information System (INIS)

Nixon, K.V.; Dowdy, E.J.; France, S.W.; Millegan, D.R.; Robba, A.A.

1983-01-01

The Advanced Nuclear Technology Group of the Los Alamos National Laboratory is now using intelligent data-acquisition and analysis instrumentation for determining the multiplication of nuclear material. Earlier instrumentation, such as the large NIM-crate systems, depended on house power and required additional computation to determine multiplication or to estimate error. The portable, battery-powered multiplication measurement unit, with advanced computational power, acquires data, calculates multiplication, and completes error analysis automatically. Thus, the multiplication is determined easily and an available error estimate enables the user to judge the significance of results

Neutron-multiplication measurement instrument

International Nuclear Information System (INIS)

Nixon, K.V.; Dowdy, E.J.; France, S.W.; Millegan, D.R.; Robba, A.A.

1982-01-01

The Advanced Nuclear Technology Group of the Los Alamos National Laboratory is now using intelligent data-acquisition and analysis instrumentation for determining the multiplication of nuclear material. Earlier instrumentation, such as the large NIM-crate systems, depended on house power and required additional computation to determine multiplication or to estimate error. The portable, battery-powered multiplication measurement unit, with advanced computational power, acquires data, calculates multiplication, and completes error analysis automatically. Thus, the multiplication is determined easily and an available error estimate enables the user to judge the significance of results

Neutron applications in materials for energy

CERN Document Server

Kearley, Gordon J

2015-01-01

Neutron Applications in Materials for Energy collects results and conclusions of recent neutron-based investigations of materials that are important in the development of sustainable energy. Chapters are authored by leading scientists with hands-on experience in the field, providing overviews, recent highlights, and case-studies to illustrate the applicability of one or more neutron-based techniques of analysis. The theme follows energy production, storage, and use, but each chapter, or section, can also be read independently, with basic theory and instrumentation for neutron scattering being

Neutron guides and scientific neutron equipment at CILAS/GMI

International Nuclear Information System (INIS)

Gautier-Picard, P.

2003-01-01

CILAS company is the world's leading supplier of complete neutron guides systems. The neutron optics with multilayer coatings produced by CILAS have become an international standard for neutron beam transportation in the modern research institutes. During the last 30 years, CILAS designed, produced and installed more than 5000 meters of guides in many European, American and Asian countries. To reinforce its leadership and presence in neutron research, CILAS acquired the company Grenoble Modular Instruments (GMI), a leading company in high precision mechanics, engineering and manufacturing of spectrometers and scientific equipment for neutron and synchrotron research. (author)

Development of instrumentation for imaging scattered cold neutrons. Phase 1 report

International Nuclear Information System (INIS)

Walter, J.

1988-01-01

The project involves the development of a cold neutron imaging array consisting of a neutron to charged particle convertor and an array of Si detector pixels. Each detector pixel has its own preamplifier/signal conditioning chain and its own data storage registers. The parallel processing capability will be contained on WSI-ASIC sub-array wafers with 196 channels per wafer. Such sub-arrays can be assembled into large focal plane arrays. The high speed of the silicon detectors and signal conditioning chains makes 100,000 cps per pixel a realistic goal. Calculations and experimental measurements of neutron detection efficiency as a function of neutron wavelength are very encouraging. Preliminary design studies of the preamplifier/signal conditioning chain appear to present no insurmountable technical problems

The development of an automatic sample-changer and control instrumentation for isotope-source neutron-activation analysis

International Nuclear Information System (INIS)

Andeweg, A.H.; Watterson, J.I.W.

1983-01-01

An automatic sample-changer was developed at the Council for Mineral Technology for use in isotope-source neutron-activation analysis. Tests show that the sample-changer can transfer a sample of up to 3 kg in mass over a distance of 3 m within 5 s. In addition, instrumentation in the form of a three-stage sequential timer was developed to control the sequence of irradiation transfer and analysis

Development of a neutron personal dose equivalent detector

International Nuclear Information System (INIS)

Tsujimura, N.; Yoshida, T.; Takada, C.; Momose, T.; Nunomiya, T.; Aoyama, K.

2007-01-01

A new neutron-measuring instrument that is intended to measure a neutron personal dose equivalent, H p (10) was developed. This instrument is composed of two parts: (1) a conventional moderator-based neutron dose equivalent meter and (2) a neutron shield made of borated polyethylene, which covers a backward hemisphere to adjust the angular dependence. The whole design was determined on the basis of MCNP calculations so as to have response characteristics that would generally match both the energy and angular dependencies of H p (10). This new instrument will be a great help in assessing the reference values of neutron H p (10) during field testing of personal neutron dosemeters in workplaces and also in interpreting their readings. (authors)

Parallel Study of HEND, RAD, and DAN Instrument Response to Martian Radiation and Surface Conditions

Science.gov (United States)

Martiniez Sierra, Luz Maria; Jun, Insoo; Litvak, Maxim; Sanin, Anton; Mitrofanov, Igor; Zeitlin, Cary

2015-01-01

Nuclear detection methods are being used to understand the radiation environment at Mars. JPL (Jet Propulsion Laboratory) assets on Mars include: Orbiter -2001 Mars Odyssey [High Energy Neutron Detector (HEND)]; Mars Science Laboratory Rover -Curiosity [(Radiation Assessment Detector (RAD); Dynamic Albedo Neutron (DAN))]. Spacecraft have instruments able to detect ionizing and non-ionizing radiation. Instrument response on orbit and on the surface of Mars to space weather and local conditions [is discussed] - Data available at NASA-PDS (Planetary Data System).

Application of instrumental neutron activation analysis and multivariate statistical methods to archaeological Syrian ceramics

International Nuclear Information System (INIS)

Bakraji, E. H.; Othman, I.; Sarhil, A.; Al-Somel, N.

2002-01-01

Instrumental neutron activation analysis (INAA) has been utilized in the analysis of thirty-seven archaeological ceramics fragment samples collected from Tal AI-Wardiate site, Missiaf town, Hamma city, Syria. 36 chemical elements were determined. These elemental concentrations have been processed using two multivariate statistical methods, cluster and factor analysis in order to determine similarities and correlation between the various samples. Factor analysis confirms that samples were correctly classified by cluster analysis. The results showed that samples can be considered to be manufactured using three different sources of raw material. (author)

Comparison of SANS instruments at reactors and pulsed sources

International Nuclear Information System (INIS)

Thiyagarajan, P.; Epperson, J.E.; Crawford, R.K.; Carpenter, J.M.; Hjelm, R.P. Jr.

1992-01-01

Small angle neutron scattering is a general purpose technique to study long range fluctuations and hence has been applied in almost every field of science for material characterization. SANS instruments can be built at steady state reactors and at the pulsed neutron sources where time-of-flight (TOF) techniques are used. The steady state instruments usually give data over small q ranges and in order to cover a large q range these instruments have to be reconfigured several times and SANS measurements have to be made. These instruments have provided better resolution and higher data rates within their restricted q ranges until now, but the TOF instruments are now developing to comparable performance. The TOF-SANS instruments, by using a wide band of wavelengths, can cover a wide dynamic q range in a single measurement. This is a big advantage for studying systems that are changing and those which cannot be exactly reproduced. This paper compares the design concepts and performances of these two types of instruments

Chemical contents in Lygeum spartum L. using instrumental neutron activation analysis

International Nuclear Information System (INIS)

Nedjimi, Bouzid

2015-01-01

The present investigation was conducted to determine the chemical contents of Lygeum spartum L. (Poaceae). Samples were analyzed in order to determine essential (Ca, K, Na, Fe, Co) and some potentially toxic elements (Eu, Sb, Tb) using instrumental neutron activation analysis (INAA). In general chemical element contents were in substantial amounts to meet adult sheep requirements. Potential intake of Ca, K, Zn, Co and Fe by ruminant weighing 50 kg BW consuming 2.0 kg per day DM was sufficient to satisfy their requirements. However, only Na level was still insufficient to meet the requirements for grazing ruminants. Potential toxic elements in this species were within the safety baseline of all the assayed elements recommended by NRC. Na supplementation would seem to be necessary in this zone, for optimum productivity of grazing animals.

Characterization of HPGe gamma spectrometric detectors systems for Instrumental Neutron Activation Analysis (INAA) at the Colombian Geological Survey

Energy Technology Data Exchange (ETDEWEB)

Sierra, O., E-mail: osierra@sgc.gov.co; Parrado, G., E-mail: gparrado@sgc.gov.co; Cañón, Y.; Porras, A.; Alonso, D.; Herrera, D. C.; Peña, M., E-mail: mlpena@sgc.gov.co; Orozco, J. [Colombian Geological Survey, Nuclear Affairs Technical Division, Neutron Activation Analysis Laboratory, Bogota D. C. (Colombia)

2016-07-07

This paper presents the progress made by the Neutron Activation Analysis (NAA) laboratory at the Colombian Geological Survey (SGC in its Spanish acronym), towards the characterization of its gamma spectrometric systems for Instrumental Neutron Activation Analysis (INAA), with the aim of introducing corrections to the measurements by variations in sample geometry. Characterization includes the empirical determination of the interaction point of gamma radiation inside the Germanium crystal, through the application of a linear model and the use of a fast Monte Carlo N-Particle (MCNP) software to estimate correction factors for differences in counting efficiency that arise from variations in sample density between samples and standards.

Time derived sigma for pulsed neutron capture logging

International Nuclear Information System (INIS)

Randall, R.R.; Fertl, W.F.; Hopkinson, E.C.

1981-01-01

The purpose of this study is to review field applications of the Atlas Neutron Lifetime Log service and to examine recent technical advances in the instrumentation and data analysis system. The major improvement to be discussed is a new method for computing /SIGMA/, the thermal neutron capture cross section of an earth formation. In the new method, the time after the neutron burst is measured for each gamma ray pulse detected by the instrumentation system within a gate of fixed width. This ''average pulse time'' is uniquely related to the thermal neutron decay rate observed in a borehole environment. The technique discussed is applicable for any condition where the neutron or gamma ray flux is time dependent. The advantages of this signal processing method, however, are most apparent for cases of rapid flux change with time, as in an exponential decay. 7 refs

Determination of selenium and zinc in rat plasma by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Munoz A, Luis.

1997-01-01

To evaluate the effects on the thyroid function when simple or multiple zinc, selenium and iodine deficiency are induced, research was carried out in laboratory animals. For simultaneously determining the Zn and Se concentration in rat plasma, an instrumental neutron activation analysis technique was applied. A clean laboratory, was used for the preparation of samples. High purity materials were used for sample collection and storage. Irradiation, decay and counting parameters were optimized to obtain the best sensitivity, accuracy and precision analysis. The Zn and Se concentrations were determined from the peak area of gamma-rays of 1115 and 265 KeV respectively. The analytical methodology used was validated with standard reference materials. The procedure used for the analysis, including the phases of collection, treatment of the samples and analytical determination was considered suitable for the study of trace elements in biological samples, especially plasma. (author) [es

Neutron production enhancements for the Intense Pulsed Neutron Source.

Energy Technology Data Exchange (ETDEWEB)

Iverson, E. B.

1999-01-04

The Intense Pulsed Neutron Source (IPNS) was the first high energy spallation neutron source in the US dedicated to materials research. It has operated for sixteen years, and in that time has had a very prolific record concerning the development of new target and moderator systems for pulsed spallation sources. IPNS supports a very productive user program on its thirteen instruments, which are oversubscribed by more than two times, meanwhile having an excellent overall reliability of 95%. Although the proton beam power is relatively low at 7 kW, the target and moderator systems are very efficient. The typical beam power which gives an equivalent flux for long-wavelength neutrons is about 60 kW, due to the use of a uranium target and liquid and solid methane moderators, precluded at some sources due to a higher accelerator power. The development of new target and moderator systems is by no means stagnant at IPNS. They are presently considering numerous enhancements to the target and moderators that offer prospects for increasing the useful neutron production by substantial factors. Many of these enhancements could be combined, although their combined benefit has not yet been well established. Meanwhile, IPNS is embarking on a coherent program of study concerning these improvements and their possible combination and implementation. Moreover, any improvements accomplished at IPNS would immediately increase the performance of IPNS instruments.

Neutron production enhancements for the Intense Pulsed Neutron Source

International Nuclear Information System (INIS)

Iverson, E. B.

1999-01-01

The Intense Pulsed Neutron Source (IPNS) was the first high energy spallation neutron source in the US dedicated to materials research. It has operated for sixteen years, and in that time has had a very prolific record concerning the development of new target and moderator systems for pulsed spallation sources. IPNS supports a very productive user program on its thirteen instruments, which are oversubscribed by more than two times, meanwhile having an excellent overall reliability of 95%. Although the proton beam power is relatively low at 7 kW, the target and moderator systems are very efficient. The typical beam power which gives an equivalent flux for long-wavelength neutrons is about 60 kW, due to the use of a uranium target and liquid and solid methane moderators, precluded at some sources due to a higher accelerator power. The development of new target and moderator systems is by no means stagnant at IPNS. They are presently considering numerous enhancements to the target and moderators that offer prospects for increasing the useful neutron production by substantial factors. Many of these enhancements could be combined, although their combined benefit has not yet been well established. Meanwhile, IPNS is embarking on a coherent program of study concerning these improvements and their possible combination and implementation. Moreover, any improvements accomplished at IPNS would immediately increase the performance of IPNS instruments

Monte Carlo study of neutronics properties of the modular storage geometry

International Nuclear Information System (INIS)

Bell, Z.W.

1995-01-01

The modular storage vault (MSV) geometry was investigated for its effects on the spectrum of neutrons from the spontaneous and induced fission of plutonium. Zinc alloy and aluminum alloy plates that will house neutron detectors and weight sensors were included. It was found that because of the large number of captures by plutonium and the steel and concrete MSV structure, only 12% of the neutron spectrum in the vicinity of the detector position was thermalized and over half of the neutrons incident on the detector position have energy in excess of 100 keV. Based on this, it is recommended that both fast and slow neutron detectors be included in the instrumentation package if plutonium is to be stored an MSV structure. No differences in the neutron spectra were found with different zinc alloys. In addition, insufficient differences in the spectra were found when aluminum was substituted for zinc to warrant any recommendation for one material over the other

The status of neutron beam utilization in Korea

International Nuclear Information System (INIS)

Shim, Hae-Seop; Lee, Chang-Hee; Seong, Baek-Seok; Lee, Jeong-Soo

1999-01-01

HANARO (30 MWth) at Korea Atomic Energy Research Institute (KAERI), which reached its first criticality on February 1995, is the multi-purpose research reactor for the application of reactor radiation in a variety of fields such as physics and materials science, irradiation technology, biomedical technology, and neutron activation analysis. For the neutron beam research, seven horizontal beam tubes of different types are available, and HANARO has performed its development plan for a basic set of neutron beam instruments since 1992. A High Resolution Powder Diffractometer (HRPD) and a Neutron Radiography Facility (NRF) has been installed and operated since 1997 and 1996 each. A Four Circle Diffractometer (FCD) and a Small Angle Neutron Spectrometer (SANS) will be operational on 1999 and in 2000 respectively, and a Polarized Neutron Spectrometer (PNS) in 2001. SANS at CN (Cold Neutron) beam tube will be operated using liquid nitrogen cooled Be filter until the cold neutron source is made available. Then, it will be moved to a guide laboratory with proper modification. Research works using the instruments in operation started by internal and external users since their full operation and have been rapidly increasing. Most in-house resources available are being used for on-going development of instruments due to rapidly increasing demands of external users nationwide. In addition to above instruments, a Triple Axis Spectrometer (TAS) and a Neutron Reflectometer which have been strongly requested by external users from universities and industries are under discussion. Then, HANARO will provide the best combination of neutron instruments to meet national research demands and international collaborations, and will be well prepared for future researches by cold neutrons. (author)

Neutron Position Sensitive Detectors for the ESS

CERN Document Server

Kirstein, Oliver; Stefanescu, Irina; Etxegarai, Maddi; Anastasopoulos, Michail; Fissum, Kevin; Gulyachkina, Anna; Höglund, Carina; Imam, Mewlude; Kanaki, Kalliopi; Khaplanov, Anton; Kittelmann, Thomas; Kolya, Scott; Nilsson, Björn; Ortega, Luis; Pfeiffer, Dorothea; Piscitelli, Francesco; Ramos, Judith Freita; Robinson, Linda; Scherzinger, Julius

2014-01-01

The European Spallation Source (ESS) in Lund, Sweden will become the world's leading neutron source for the study of materials. The instruments are being selected from conceptual proposals submitted by groups from around Europe. These instruments present numerous challenges for detector technology in the absence of the availability of Helium-3, which is the default choice for detectors for instruments built until today and due to the extreme rates expected across the ESS instrument suite. Additionally a new generation of source requires a new generation of detector technologies to fully exploit the opportunities that this source provides. The detectors will be sourced from partners across Europe through numerous in-kind arrangements; a process that is somewhat novel for the neutron scattering community. This contribution presents briefly the current status of detectors for the ESS, and outlines the timeline to completion. For a conjectured instrument suite based upon instruments recommended for construction, ...

Polarimetric neutron scattering

International Nuclear Information System (INIS)

Tasset, F.

2001-01-01

Polarimetric Neutron Scattering in introduced, both by, explaining methodological issues and the corresponding instrumental developments. After a short overview of neutron spin polarization and the neutron polarization 3d-vector a pictorial approach of the microscopic theory is used to show how a polarized beam interacts with lattice and magnetic Fourier components in a crystal. Examples are given of using Spherical Neutron Polarimetry (SNP) and the corresponding Cryopad polarimeter for the investigation of non-collinear magnetic structures. (R.P.)

Mixed field dose equivalent measuring instruments

International Nuclear Information System (INIS)

Brackenbush, L.W.; McDonald, J.C.; Endres, G.W.R.; Quam, W.

1985-01-01

In the past, separate instruments have been used to monitor dose equivalent from neutrons and gamma rays. It has been demonstrated that it is now possible to measure simultaneously neutron and gamma dose with a single instrument, the tissue equivalent proportional counter (TEPC). With appropriate algorithms dose equivalent can also be determined from the TEPC. A simple ''pocket rem meter'' for measuring neutron dose equivalent has already been developed. Improved algorithms for determining dose equivalent for mixed fields are presented. (author)

Neutron dosimeters and survey meters in accelerators, reactors and other neutron environments

International Nuclear Information System (INIS)

1989-03-01

Neutron fields in occupationally accessible areas around nuclear reactors, radioisotope sources and medical and high energy accelerators have been characterized using currently available information. Neutron, rem meters, such as the Leake detector, are the most suitable instruments available for conducting neutron dose rate surveys in the vicinity of radioisotope neutron sources, nuclear reactors and medical accelerators. However, these instruments have been shown to be deficient in that they overrespond by a factor of four to neutrons in the 0.1 to 1 MeV range and are insensitive to neutrons from about 1 eV up to about 10 keV. Also, they are insensitive to neutrons above 20 MeV and their use must be restricted near high energy accelerators where significant numbers of neutrons above 20 MeV are known to be present. The most suitable instrument of measure dose from neutrons above 20 MeV is the 12 C(n,2n) 11 C scintillation chamber. Commercially available rem meters frequently use BF 3 counters in the pulse mode to detect thermal neutrons. Therefore, measurements around pulsed accelerators must be made with caution to ensure that the detector is not saturated during each pulse and that the accelerator pulse period is greater than the response time of the detector. The personal neutron dosimeters currently available either are known to be insensitive to neutrons above 20 MeV or have not been tested. Also, all except the albedo dosimeter are insensitive to or have not been tested for neutron energies in the range 1 eV to 10 keV. Several dosimeter types respond reasonably well to neutrons in the energy range 0.1 to 15 MeV, for example, CR-39, bubble and superheated drop detectors. However, the first gas a lower limit of sensitivity of about 0.3 mSv. The bubble detector can be designed to measure doses as small as 1μSv and offers the additional benefit of direct-reading capability. The superheated drop detector is not suitable for use around pulsed accelerators because

Characterization of the new neutron imaging and materials science facility IMAT

Science.gov (United States)

Minniti, Triestino; Watanabe, Kenichi; Burca, Genoveva; Pooley, Daniel E.; Kockelmann, Winfried

2018-04-01

IMAT is a new cold neutron imaging and diffraction instrument located at the second target station of the pulsed neutron spallation source ISIS, UK. A broad range of materials science and materials testing areas will be covered by IMAT. We present the characterization of the imaging part, including the energy-selective and energy-dispersive imaging options, and provide the basic parameters of the radiography and tomography instrument. In particular, detailed studies on mono and bi-dimensional neutron beam flux profiles, neutron flux as a function of the neutron wavelength, spatial and energy dependent neutron beam uniformities, guide artifacts, divergence and spatial resolution, and neutron pulse widths are provided. An accurate characterization of the neutron beam at the sample position, located 56 m from the source, is required to optimize collection of radiographic and tomographic data sets and for performing energy-dispersive neutron imaging via time-of-flight methods in particular.

Workshop on the next plan for the study of 'physics of fast neutron reactions and measurements'

International Nuclear Information System (INIS)

1985-03-01

A work shop titled ''Physics of fast neutron reaction and measurements'' was held on 25 December 1984, where discussions were made on the new approach and techniques for neutron measurements. The possibilities of experimental tests with AVF cyclotron was also discussed. The followings are the list of papers presented at the work shop (all papers are written in Japanese except for the abstracts). (1) Monoenergetic neutron beam in Tohoku Cyclotron. (2) Spin-dependent response probed in (p,n) and (n,p) reactions. (3) Measurement of D(n,p) 2n reaction and instrumentation for (n,x) reactions in the 40 - 80 MeV region. (4) Two comments related to the neutron reaction. (5) High energy neutron production facilities in the world and a possibility of neutron induced reaction experiments at RCNP. (6) A neutron counter by detection of recoil protons with solid state detectors and development of neutron source by heavy ions. (7) The measurement of neutrons with the recoil detector. (8) Polarization transfer measurements (Py, Dss, Ds 1 , · · ·) with fast neutron beams. (9) Neutron elastic scattering. (10) Neutron capture gamma reaction and effective charge. (11) Comparison between neutron and charged particle induced reactions. (12) Study of giant resonances by fast neutrons. (Aoki, K.)

Design study of a time-of-flight neutron spectrometer for JT-60U

International Nuclear Information System (INIS)

Elevant, T.; Hoek, M.; Nishitani, Takeo.

1993-06-01

A time-of-flight neutron spectrometer is proposed for measurements of neutron energy spectra from deuterium-deuterium reactions in JT-60U tokamak plasmas. The sensitivity of the instrument is 2 · 10 -2 cm 2 , energy resolution is 4.5 % (FWHM) and maximum useful count-rate is 6 kHz. Analysis of neutron energy spectra will provide information on central ion temperatures larger than ∼ 4 keV with an accuracy of ± 10 %, and neutron source fraction from reactions between thermal ions with an accuracy of ± 15 %. The minimum time required for data acquisition is 0.1 s. (author)

Comparison of neutron scattering and DFM capacitance instruments ...

African Journals Online (AJOL)

Soil water evaporation is an important parameter that needs to be accurately measured for the design of water-efficient agricultural systems. With this study, the abilities of the DFM capacitance probes and a neutron water meter (NWM) to measure evaporation from the soil surface were compared. Measured evaporation was ...

A Neutron Rem Counter

Energy Technology Data Exchange (ETDEWEB)

Andersson, I Oe; Braun, J

1964-01-15

A neutron detector is described which measures the neutron dose rate in rem/h independently of the energy of the neutrons from thermal to 15 MeV. The detector consists of a BF{sub 3} proportional counter surrounded by a shield made of polyethylene and boron plastic that gives the appropriate amount of moderation and absorption to the impinging neutrons to obtain rem response. Two different versions have been developed. One model can utilize standard BF{sub 3} counters and is suitable for use in installed monitors around reactors and accelerators and the other model is specially designed for use in a portable survey instrument. The neutron rem counter for portable instruments has a sensitivity of 2.4 cps/mrem/h and is essentially nondirectional in response. With correct bias setting the counter is insensitive to gamma exposure up to 200 r/h from Co-60.

Dynamically polarized samples for neutron protein crystallography at the Spallation Neutron Source

International Nuclear Information System (INIS)

Zhao, Jinkui; Pierce, Josh; Robertson, J. L.; Herwig, Kenneth W.; Myles, Dean; Cuneo, Matt; Li, Le; Meilleur, Flora; Standaert, Bob

2016-01-01

To prepare for the next generation neutron scattering instruments for the planned second target station at the Spallation Neutron Source (SNS) and to broaden the scientific impact of neutron protein crystallography at the Oak Ridge National Laboratory, we have recently ramped up our efforts to develop a dynamically polarized target for neutron protein crystallography at the SNS. Proteins contain a large amount of hydrogen which contributes to incoherent diffraction background and limits the sensitivity of neutron protein crystallography. This incoherent background can be suppressed by using polarized neutron diffraction, which in the same time also improves the coherent diffraction signal. Our plan is to develop a custom Dynamic Nuclear Polarization (DNP) setup tailored to neutron protein diffraction instruments. Protein crystals will be polarized at a magnetic field of 5 T and temperatures of below 1 K. After the dynamic polarization process, the sample will be brought to a frozen-spin mode in a 0.5 T holding field and at temperatures below 100 mK. In a parallel effort, we are also investigating various ways of incorporating polarization agents needed for DNP, such as site specific spin labels, into protein crystals. (paper)

Designing new guides and instruments using McStas

CERN Document Server

Farhi, E; Wildes, A R; Ghosh, R; Lefmann, K

2002-01-01

With the increasing complexity of modern neutron-scattering instruments, the need for powerful tools to optimize their geometry and physical performances (flux, resolution, divergence, etc.) has become essential. As the usual analytical methods reach their limit of validity in the description of fine effects, the use of Monte Carlo simulations, which can handle these latter, has become widespread. The McStas program was developed at Riso National Laboratory in order to provide neutron scattering instrument scientists with an efficient and flexible tool for building Monte Carlo simulations of guides, neutron optics and instruments. To date, the McStas package has been extensively used at the Institut Laue-Langevin, Grenoble, France, for various studies including cold and thermal guides with ballistic geometry, diffractometers, triple-axis, backscattering and time-of-flight spectrometers. In this paper, we present some simulation results concerning different guide geometries that may be used in the future at th...

Neutron scattering. Annual progress report 1997; Neutronenstreuung. Annual progress report 1997

Energy Technology Data Exchange (ETDEWEB)

Allenspach, P.; Boeni, B.; Fischer, P.; Furrer, A. [Eidgenoessische Technische Hochschule, Zurich (Switzerland). Lab. fuer Neutronenstreuung

1998-02-01

The present progress report describes the scientific and technical activities obtained by LNS staff members in 1997. It also includes the work performed by external groups at our CRG instruments D1A and IN3 at the ILL Grenoble. Due to the outstanding properties of neutrons and x-rays the research work covered many areas of science and materials research. The highlight of the year 1997 was certainly the production of neutrons at the new spallation neutron source SINQ. From July to November, SINQ was operating for typically two days/week and allowed the commissioning of four instruments at the neutron guide system: - the triple-axis spectrometer Druechal, - the powder diffractometer DMC, - the double-axis diffractometer TOPSI, the polarised triple-axis spectrometer TASP. These instruments are now fully operational and have already been used for condensed matter studies, partly in cooperation with external groups. Five further instruments are in an advanced state, and their commissioning is expected to occur between June and October 1998: - the high-resolution powder diffractometer HRPT, - the single-crystal diffractometer TriCS, - the time-of-flight spectrometer FOCUS, - the reflectometer AMOR, - the neutron optical bench NOB. Together with the small angle neutron scattering facility SANS operated by the spallation source department, all these instruments will be made available to external user groups in the future. (author) figs., tabs., refs.

Status and neutron scattering experiments at KENS

International Nuclear Information System (INIS)

Watanabe, N.; Sasaki, H.; Ishikawa, Y.; Endoh, Y.; Inoue, K.

1983-01-01

This paper reports present status of the KENS facility, progress in neutron scattering experiments and instrumental developments, and status of the KENS-I' program. A design study of a high intensity rapid-cycle 800 MeV proton synchrotron for proposed new pulsed neutron (KENS-II) and meson source is also descirbed

Solid state neutron dosimeter for space applications. Final Report

International Nuclear Information System (INIS)

Entine, G.; Nagargar, V.; Sharif, D.

1990-08-01

Personnel engaged in space flight are exposed to significant flux of high energy neutrons arising from both primary and secondary sources of ionizing radiation. Presently, there exist no compact neutron sensor capable of being integrated in a flight instrument to provide real time measurement of this radiation flux. A proposal was made to construct such an instrument using special PIN silicon diode which has the property of being insensitive to the other forms of ionizing radiation. Studies were performed to determine the design and construction of a better reading system to allow the PIN diode to be read with high precision. The physics of the device was studied, especially with respect to those factors which affect the sensitivity and reproducibility of the neutron response. This information was then used to develop methods to achieve high sensitivity at low neutron doses. The feasibility was shown of enhancing the PIN diode sensitivity to make possible the measurement of the low doses of neutrons encountered in space flights. The new PIN diode will make possible the development of a very compact, accurate, personal neutron dosimeter

Determination of uranium and thorium in rock samples from Harargaj Anticline by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Rahman, M.; Molla, N.I.; Sharif, A.K.M.; Basunia, S.; Islam, S.; Miah, R.U.; Hossain, S.M.; Chowdhury, M.I.; Bhuiyan, A.D.; Stegnar, P.

1993-01-01

Uranium and thorium were determined in geological materials such as radioactive rock samples collected from the Harargaj Anticline in Moulavi Bazar. The pure instrumental neutron activation analysis (INAA) technique was used in qualitative and quantitative analysis of the rock samples for U and Th. The samples were properly prepared together with their standards and simultaneously irradiated in a neutron flux of the order of 10 12 n*cm -2 *s -1 using the TRIGA MARK II research reactor facility at the AERE, Savar, Dhaka. After activation the samples were subjected to γ-ray spectrometry using a high purity germanium detection system. As a result of the analysis, U and Th could be determined. The data are consistent with the values reported by the ground radiometric survey group for some of the samples. (author) 7 refs.; 1 fig.; 2 tabs

Development of a polarized neutron beam line at Algerian research reactors using McStas software

Energy Technology Data Exchange (ETDEWEB)

Makhloufi, M., E-mail: makhloufi_8m@yahoo.fr [Centre de Recherche Nucléaire de Birine (Algeria); Salah, H. [Centre de Recherche Nucléaire d' Alger (Algeria)

2017-02-01

Unpolarized instrumentation has long been studied and designed using McStas simulation tool. But, only recently new models were developed for McStas to simulate polarized neutron scattering instruments. In the present contribution, we used McStas software to design a polarized neutron beam line, taking advantage of the available spectrometers reflectometer and diffractometer in Algeria. Both thermal and cold neutron was considered. The polarization was made by two types of supermirrors polarizers FeSi and CoCu provided by the HZB institute. For sake of performance and comparison, the polarizers were characterized and their characteristics reproduced. The simulated instruments are reported. Flipper and electromagnets for guide field are developed. Further developments including analyzers and upgrading of the existing spectrometers are underway. - Highlights: • Permit to evaluate the feasibility of a polarized neutron scattering instrument prior to its implementation. • Help to understand the origin of instrumental imperfections and offer an optimized set up configuration. • Provide the possibility to use the FeSi and CoCu supermirrors, designed to polarize spin up cold neutron, to polarize thermal neutron.

Development of a polarized neutron beam line at Algerian research reactors using McStas software

International Nuclear Information System (INIS)

Makhloufi, M.; Salah, H.

2017-01-01

Unpolarized instrumentation has long been studied and designed using McStas simulation tool. But, only recently new models were developed for McStas to simulate polarized neutron scattering instruments. In the present contribution, we used McStas software to design a polarized neutron beam line, taking advantage of the available spectrometers reflectometer and diffractometer in Algeria. Both thermal and cold neutron was considered. The polarization was made by two types of supermirrors polarizers FeSi and CoCu provided by the HZB institute. For sake of performance and comparison, the polarizers were characterized and their characteristics reproduced. The simulated instruments are reported. Flipper and electromagnets for guide field are developed. Further developments including analyzers and upgrading of the existing spectrometers are underway. - Highlights: • Permit to evaluate the feasibility of a polarized neutron scattering instrument prior to its implementation. • Help to understand the origin of instrumental imperfections and offer an optimized set up configuration. • Provide the possibility to use the FeSi and CoCu supermirrors, designed to polarize spin up cold neutron, to polarize thermal neutron.

Spallation Neutron Source Second Target Station Integrated Systems Update

Energy Technology Data Exchange (ETDEWEB)

Ankner, John Francis [ORNL; An, Ke [ORNL; Blokland, Willem [ORNL; Charlton, Timothy R. [ORNL; Coates, Leighton [ORNL; Dayton, Michael J. [ORNL; Dean, Robert A. [ORNL; Dominguez-Ontiveros, Elvis E. [ORNL; Ehlers, Georg [ORNL; Gallmeier, Franz X. [ORNL; Graves, Van B. [ORNL; Heller, William T. [ORNL; Holmes, Jeffrey A. [ORNL; Huq, Ashfia [ORNL; Lumsden, Mark D. [ORNL; McHargue, William M. [ORNL; McManamy, Thomas J. [ORNL; Plum, Michael A. [ORNL; Rajic, Slobodan [ORNL; Remec, Igor [ORNL; Robertson, Lee [ORNL; Sala, Gabriele [ORNL; Stoica, Alexandru Dan [ORNL; Trotter, Steven M. [ORNL; Winn, Barry L. [ORNL; Abudureyimu, Reheman [ORNL; Rennich, Mark J. [ORNL; Herwig, Kenneth W. [ORNL

2017-04-01

The Spallation Neutron Source (SNS) was designed from the beginning to accommodate both an accelerator upgrade to increase the proton power and a second target station (STS). Four workshops were organized in 2013 and 2014 to identify key science areas and challenges where neutrons will play a vital role [1-4]. Participants concluded that the addition of STS to the existing ORNL neutron sources was needed to complement the strengths of High Flux Isotope Reactor (HFIR) and the SNS first target station (FTS). To address the capability gaps identified in the workshops, a study was undertaken to identify instrument concepts that could provide the required new science capabilities. The study outlined 22 instrument concepts and presented an initial science case for STS [5]. These instrument concepts formed the basis of a planning suite of instruments whose requirements determined an initial site layout and moderator selection. An STS Technical Design Report (TDR) documented the STS concept based on those choices [6]. Since issue of the TDR, the STS concept has significantly matured as described in this document.

A proposed experiment for studying the direct neutron-neutron interaction

International Nuclear Information System (INIS)

Hassan Fikry, A.R.; Maayouf, R.M.A.

1979-01-01

An experiment for studying the direct neutron-neutron interaction is suggested. The experiment is based on the combined use of an accelerator, e.g., an electron linear accelerator, together with a mobile pulsed reactor; or using a pulsed beam reactor together with a mobile neutron generator

Epiboron instrumental neutron activation analysis for the determination of iodine in various salt samples

International Nuclear Information System (INIS)

Nyarko, B.J.B.; Serfor-Armah, Y.; Osae, S.; Akaho, E.H.K.; Anim-Sampong, S.; Maakuu, B.T.

2001-01-01

Epiboron instrumental neutron activation analysis (EINAA) using flexible boron as thermal neutron filter, has been used to analyze several salt samples obtained from various markets in Ghana for iodine. The method involves the irradiation of samples in boron carbide-lined polyethylene vials at the outer irradiation site of the Ghana Research Reactor-1 (GHARR-1). The samples were then counted directly without any pre-treatment on a Canberra N-type HPGe detector. The qualitative and quantitative analyses were done using the 443 keV photopeak of 128 I. The precision and accuracy of the method have been evaluated and the detection limits of the various samples were calculated. The values of iodine determined in the iodized salt range between 10.0 and 210 ppm. For non-iodinated salts, iodine levels were below 500 ppb. The values obtained show great variations among the salt samples, sample collection time and from market to market. This results show that the method can be successfully applied in the determination of trace amount of iodine in salt samples without any chemical separation. (author)

Determination of arsenic and mercury in facial cosmetics by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Bravo Martinez, J.

1979-01-01

The presence of arsenic and mercury in some chilean facial cosmetics was investiged. Since in Chile there is no regulations dealing with the maximum permisible concentration of some chemical elements in cosmetics products, the national industry control neither the presence nor the quantity, if any, of those elements. The study was performed on compact or powder eye shadows by means of instrumental neutron activation analysis. The samples were analized without any chemical treatment and with minimum manipulation to avoid any possible contamination. A total of 67 samples from 9 different cosmetic industries were analysed. Arsenic was detected and determined quantitatively in 46 samples, ranging from 0.32 to 136 ppm. Mercury was not detected in any sample. The contamination of arsenic is due to the high concentration of this element in some of the raw material used in the manufacturing of the cosmetics, as was demonstrated by the analysis of these materials. (EC)

Neutron measuring instruments for radiation protection

International Nuclear Information System (INIS)

Heinzelmann, M.; Schneider, W.; Hoefert, M.; Kuehn, H.; Jahr, R.; Wagner, S.; Piesch, E.

1979-09-01

The present report deals with selected topics from the field of neutron dosimetry for radiation protection connected with the work of the subcommittee 6802 in the Standards Committee on Radiology (NAR) of the German Standards Institute (DIN). It is a sort of material collection. The topics are: 1. Measurement of the absorbed-energy dose by a) ionization chambers in fields of mixed radiation and b) recoil-proton proportional counting tubes. 2. Measurement of the equivalent dose, neutron monitors, combination methods by a) rem-meters, b) recoil-proton counting tubes, c) recombination method, tissue-equivalent proportional counters, activation methods for high energies in fields of mixed radiation, d) personnel dosimetry by means of ionization chambers and counting tubes, e) dosimetry by means of activation methods, nuclear track films, nonphotographic nuclear track detectors and solid-state dosimeters. (orig./HP) [de

Determination of zinc concentration in female reproductive system by instrumental neutron activation

International Nuclear Information System (INIS)

Carvalho, Fernando Ramos de

2009-01-01

Non-surgical female sterilization through the transcervical insertion of quinacrine pellets was considered a definitive, low-cost, safe and effective contraceptive method. The zinc, present in both uterus and Fallopian tubes, inhibit the quinacrine efficiency. The addition of copper increases the efficacy of quinacrine, reducing the risk of pregnancy due to the failure to obstruct the Fallopian tubes. The copper neutralized the deleterious effect of the zinc and so the treatment efficacy is increased. In order to obtain a mapping to study the zinc content in the female reproductive system, samples of both uterus and Fallopian tubes were analyzed by instrumental neutron activation. The results show that, on average, the obtained zinc concentrations in tubes (89 μg-g -1 ) is lower than in the uterus (118 μg-g -1 ), confirming results obtained by other authors. These results will support a research project about non-surgical female sterilization of the 'Faculdade de Medicina da Universidade Federal de Minas Gerais' (Medical School of Federal University of Minas Gerais). The used methodology and obtained results are here reported. (author)

Determination of zinc concentration in female reproductive system by instrumental neutron activation

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Fernando Ramos de, E-mail: framosc@oi.com.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear; Oliveira, Arno Heeren de, E-mail: heeren@nuclear.ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina. Dept. de Ginecologia e Obstetricia; Ferreira, Claudia R.C.; Ferreira, Ricardo Alberto Neto; Menezes, Maria Angela de B.C., E-mail: claudia@medicina.ufmg.b, E-mail: ranf@cdtn.b, E-mail: menezes@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2009-07-01

Non-surgical female sterilization through the transcervical insertion of quinacrine pellets was considered a definitive, low-cost, safe and effective contraceptive method. The zinc, present in both uterus and Fallopian tubes, inhibit the quinacrine efficiency. The addition of copper increases the efficacy of quinacrine, reducing the risk of pregnancy due to the failure to obstruct the Fallopian tubes. The copper neutralized the deleterious effect of the zinc and so the treatment efficacy is increased. In order to obtain a mapping to study the zinc content in the female reproductive system, samples of both uterus and Fallopian tubes were analyzed by instrumental neutron activation. The results show that, on average, the obtained zinc concentrations in tubes (89 mug-g{sup -1}) is lower than in the uterus (118 mug-g{sup -1}), confirming results obtained by other authors. These results will support a research project about non-surgical female sterilization of the 'Faculdade de Medicina da Universidade Federal de Minas Gerais' (Medical School of Federal University of Minas Gerais). The used methodology and obtained results are here reported. (author)

Powder neutron diffractometers HRPT and DMCG

Energy Technology Data Exchange (ETDEWEB)

Fischer, P; Doenni, A; Staub, U; Zolliker, M [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

1996-11-01

Basic properties and applications of SINQ powder neutron diffractometers are described. For optimum use of the continuous neutron beams these instruments are equipped with position sensitive detectors, and both high-intensity and high-resolution modes of operation are possible. HRPT attaining resolutions {delta}d/d{<=}10{sup -3}, d=lattice spacing, at a thermal neutron channel of the target station and DMCG at a cold neutron guide coated with m=2 supermirrors, are complementary concerning the applications: the former will be mainly used for structural studies and the latter to investigate magnetic ordering phenomena. (author) figs., tabs., refs.

Neutron Imaging at Compact Accelerator-Driven Neutron Sources in Japan

Directory of Open Access Journals (Sweden)

Yoshiaki Kiyanagi

2018-03-01

Full Text Available Neutron imaging has been recognized to be very useful to investigate inside of materials and products that cannot be seen by X-ray. New imaging methods using the pulsed structure of neutron sources based on accelerators has been developed also at compact accelerator-driven neutron sources and opened new application fields in neutron imaging. The world’s first dedicated imaging instrument at pulsed neutron sources was constructed at J-PARC in Japan owing to the development of such new methods. Then, usefulness of the compact accelerator-driven neutron sources in neutron science was recognized and such facilities were newly constructed in Japan. Now, existing and new sources have been used for neutron imaging. Traditional imaging and newly developed pulsed neutron imaging such as Bragg edge transmission have been applied to various fields by using compact and large neutron facilities. Here, compact accelerator-driven neutron sources used for imaging in Japan are introduced and some of their activities are presented.

Iron Quadrangle, Brazil. Elemental concentration determined by k0-instrumental neutron activation analysis. Part 2. Kale samples

International Nuclear Information System (INIS)

Menezes, M.A.B.C.; Palmieri, H.E.L.; Leonel, L.V.; Nalini, H.A.Jr.; Jacimovic, R.

2006-01-01

The objective of this study was to evaluate the influence of mining activity on elemental concentrations in kale grown around a mining area. Two sites studied are in the Iron Quadrangle, Minas Gerais, Brazil, considered one of the richest mineral-bearing regions in the world. One site is near mineral exploration activity and the other is an ecological area. A comparator site outside the Iron Quadrangle was also analyzed. This work focused on the determination of the elemental concentrations in kale applying the k 0 -instrumental neutron activation analysis. As the Brazilian legislation specifies values for soil only, the results for kale were compared to the literature values and it was found that the vegetable does not present any health risks. (author)

Study on the mercury evolution in a laboratory multi specific aquatic system by using instrumental neutron activation analysis

International Nuclear Information System (INIS)

Bubach, Debora; Guevara, Sergio Ribeiro; Arribere, Maria A.; Pechen de d'Angelo, Ana; Ferrari, Ana; Venturino, Andres

1999-01-01

A preliminary study on the evolution of mercury in the organisms of a laboratory multi specific aquatic system was performed using Instrumental Neutron Activation Analysis (INAA). Some of the possible effects of mercury toxicity were monitored by analyzing early biochemical indicators. The system consisted of an aquarium with bed sediments, aquatic macrophytes (Myriophyllum sp.), bivalves (Diplodom sp.) and exotic fish, simulating a long term contamination situation of unknown causes, where the sediments are the contaminant reservoir. Samples of the abiotic components of the system were analyzed at the beginning of the experiment, and again when the organisms were sampled. Fish carcass, kidney and liver samples, bivalve hepatopancreas, and whole macrophytes were extracted ana analyzed for mercury and other elements by INAA at the beginning of the experiment, and after 48 and 96 hours. Since some crustal elements such as Sc and La were detected in the hepatopancreas and macrophyte samples, enrichment factors for mercury, with respect to the <63 μm sediment fraction, were computed to discriminate the metabolized Hg content from that associated to the particulate. The hepatopancreas index, some indicators of oxidative stress (γ-Glutamyl-cysteinyl-glycine content and lipid peroxidation) and brain acetilcolinesterasa were measured as early indicators of toxicity. (author)

A simulation report for the neutron guide development at HANARO

International Nuclear Information System (INIS)

Cho, S. J.; Soo, J. Y.; Seong, B. S.; Lee, C. H.; Kim, H. R.

2006-04-01

Lately, a demand of the measurement technique on atomic scale has been exceedingly increased over the whole field of the basic and technical science such as biotechnology, nano-technology, solid state physics, solid chemistry etc. Therefore a project called 'infrastructure construction for cold neutron research and utilization technique development' was launched in KAERI in July 2003, in order to raise a domestic basic science with an international level and elevate a international competitiveness for the bio-, nano- and informatics technology area through a wide contribution in a material structure research field. In order to accomplish this project until 2008, some important developments were launched at a same time such as a cold neutron source which shifts neutrons from a short wavelength range to a long wavelength, a system driving part for a smooth operation of a cold neutron source, and a neutron guide tube to be able to send neutrons to spectrometers located over a long distance. The guide simulation should be preferentially performed for an effective use of expensive neutron to meet the requirements such as wavelengths and type of instruments, experimental space, interferences with other instruments. The objective of this study was to decide guide shape, dimension, amount, curvature and instrument layout

Exploring the structure of biological macromolecules in solution using Quokka, the small angle neutron scattering instrument, at ANSTO

International Nuclear Information System (INIS)

Wood, Kathleen; Jeffries, Cy M.; Knott, Robert B.; Sokolova, Anna; Jacques, David A.; Duff, Anthony P.

2015-01-01

Small angle neutron scattering (SANS) is widely used to extract structural parameters, shape and other types of information from a vast array of materials. The technique is applied to biological macromolecules and their complexes in solution to reveal information often not accessible by other techniques. SANS measurements on biomolecules present some particular challenges however, one of which is suitable instrumentation. This review details SANS experiments performed on two well-characterised globular proteins (lysozyme and glucose isomerase) using Quokka, the recently commissioned SANS instrument at the Australian Nuclear Science and Technology Organisation (ANSTO). The instrument configuration as well as data collection and reduction strategies for biological investigations are discussed and act as a general reference for structural biologists who use the instrument. Both model independent analysis of the two proteins and ab initio modelling illustrate that Quokka-SANS data can be used to successfully model the overall shapes of proteins in solution, providing a benchmark for users

Determination of the elemental distribution in cigarette components and smoke by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Wu, D.; Landsberger, S.; Larson, S.M.

1997-01-01

Cigarette smoking is a major source of particle released in indoor environments. A comprehensive study of the elemental distribution in cigarettes and cigarette smoke has been completed. Specifically, concentrations of thirty elements have been determined for the components of 15 types of cigarettes. Components include tobacco, ash, butts, filters, and cigarette paper. In addition, particulate matter from mainstream smoke (MS) and sidesstream smoke (SS) were analyzed. The technique of elemental determination used in the study is instrumental neutron activation analysis. The results show that certain heavy metals, such as As, Cd, K, Sb and Zn, are released into the MS and SS. These metals may then be part of the health risk of exposure to smoke. Other elements are retained, for the most part, in cigarette ash and butts. The elemental distribution among the cigarette components and smoke changes for different smoking conditions. (author)

The experimental method for neutron dose-equivalent detection

International Nuclear Information System (INIS)

Ji Changsong

1992-01-01

A new method, for getting neutron dose-equivalent Cd rode absorption method is described. The method adopts Cd-rode-swarm buck absorption, which greatly improved the neutron sensitivity and simplified the adjustment method. By this method, the author has developed BH3105 model neutron dose equivalent meter, the sensitivity of this instrument reach 10 cps/μSvh -1 . γ-ray depression rate reaches 4000:1, the measurement range is 0.1 μSv/h-10 6 μSv/h. The energy response is good (from thermal neutron-14 MeV neutron), this instrument can be used to measure the dose equivalent of the neutron areas

5 MW pulsed spallation neutron source, Preconceptual design study

Energy Technology Data Exchange (ETDEWEB)

1994-06-01

This report describes a self-consistent base line design for a 5 MW Pulsed Spallation Neutron Source (PSNS). It is intended to establish feasibility of design and as a basis for further expanded and detailed studies. It may also serve as a basis for establishing project cost (30% accuracy) in order to intercompare competing designs for a PSNS not only on the basis of technical feasibility and technical merit but also on the basis of projected total cost. The accelerator design considered here is based on the objective of a pulsed neutron source obtained by means of a pulsed proton beam with average beam power of 5 MW, in {approx} 1 {mu}sec pulses, operating at a repetition rate of 60 Hz. Two target stations are incorporated in the basic facility: one for operation at 10 Hz for long-wavelength instruments, and one operating at 50 Hz for instruments utilizing thermal neutrons. The design approach for the proton accelerator is to use a low energy linear accelerator (at 0.6 GeV), operating at 60 Hz, in tandem with two fast cycling booster synchrotrons (at 3.6 GeV), operating at 30 Hz. It is assumed here that considerations of cost and overall system reliability may favor the present design approach over the alternative approach pursued elsewhere, whereby use is made of a high energy linear accelerator in conjunction with a dc accumulation ring. With the knowledge that this alternative design is under active development, it was deliberately decided to favor here the low energy linac-fast cycling booster approach. Clearly, the present design, as developed here, must be carried to the full conceptual design stage in order to facilitate a meaningful technology and cost comparison with alternative designs.

5 MW pulsed spallation neutron source, Preconceptual design study

International Nuclear Information System (INIS)

1994-06-01

This report describes a self-consistent base line design for a 5 MW Pulsed Spallation Neutron Source (PSNS). It is intended to establish feasibility of design and as a basis for further expanded and detailed studies. It may also serve as a basis for establishing project cost (30% accuracy) in order to intercompare competing designs for a PSNS not only on the basis of technical feasibility and technical merit but also on the basis of projected total cost. The accelerator design considered here is based on the objective of a pulsed neutron source obtained by means of a pulsed proton beam with average beam power of 5 MW, in ∼ 1 μsec pulses, operating at a repetition rate of 60 Hz. Two target stations are incorporated in the basic facility: one for operation at 10 Hz for long-wavelength instruments, and one operating at 50 Hz for instruments utilizing thermal neutrons. The design approach for the proton accelerator is to use a low energy linear accelerator (at 0.6 GeV), operating at 60 Hz, in tandem with two fast cycling booster synchrotrons (at 3.6 GeV), operating at 30 Hz. It is assumed here that considerations of cost and overall system reliability may favor the present design approach over the alternative approach pursued elsewhere, whereby use is made of a high energy linear accelerator in conjunction with a dc accumulation ring. With the knowledge that this alternative design is under active development, it was deliberately decided to favor here the low energy linac-fast cycling booster approach. Clearly, the present design, as developed here, must be carried to the full conceptual design stage in order to facilitate a meaningful technology and cost comparison with alternative designs

Characteristic Elemental Composition of Oil Pigments using Instrumental Neutron Activation Analysis

International Nuclear Information System (INIS)

Chung, Yong Sam; Kim, Sun Ha; Sun, Gwang Min; Lim, Jong Myung; Moon, Jong Hwa; Kim, Young Jin; Lim, Sung Jin; Song, Yu Na; Kim, Ken

2009-01-01

The principal aim of this study is to identify the applicability of instrumental neutron activation analysis as a non-destructive examination tool for the quantitative composition analysis associated with authentication, restoration, and conservation of art objects in the field of cultural heritage. Generally, the chemical composition of pigments are associated with the colors such as white, yellow, orange, red, green, blue and black, and it varies with raw materials of pigments. According to the colors of a different pigments, chemical compositions are as follows; for example, white pigments were used for a mixture of Pb(CO 3 ) 2 , PbSO 4 , PbO, Pb(OH) 2 , ZnO, ZnS, TiO 2 , BaSO 4 , CaCO 3 , Al 2 O 3 , As 2 S 3 , etc.; black pigments were series of carbon black, borne ash, MnO+Mn 2 O 3 , etc.; red pigments were Fe 2 O 3 , Pb 3 O 4 , HgS, PbMo 4 , CdS+CdSe, etc.; brown and yellow pigments were PbCrO 4 , ZnCrO 4 , CdS-ZnS, K 3 [Co(NO 2 ) 6 ], Pb(SbO 3 ) 2 , C 19 H 16 O 11 Mg, SrCrO 4 , etc.; green pigments were Cr 2 O 3 , Cr 2 O(OH) 4 , Cu(C 2 H 3 O 2 )-2Cu(OH) 2 ), Cr 2 O 3 -Al 2 O 3 -CoO, etc.; blue pigments were Fe 4 [Fe(CN) 6 ] 3 , CoO-Al 2 O 3 , Na 8 - 10 Al 6 Si 6 O 24 S 2-4 , etc. This first step is to obtain quantitative data on the concentrations of major, minor and trace elements in oil pigments and to explain pigment sources by statistical treatment as reported in many literatures. The determination of major, minor and micro elements in the subject materials are essential in many fields of basic science and technology as well as commercial and industrial fields. In particular, direct analysis of a sample offers a more effective investigation method in these fields. Instrumental neutron activation analysis (INAA) has an inherent advantage of being a non-destructive, simultaneously multi-elemental analysis with high accuracy and sensitivity. In order to characterize the elemental contents of art objects, the quantitative analysis of oil pigment series was

Feasibility and applications of the spin-echo modulation option for a small angle neutron scattering instrument at the European Spallation Source

Science.gov (United States)

Kusmin, A.; Bouwman, W. G.; van Well, A. A.; Pappas, C.

2017-06-01

We describe theoretical and practical aspects of spin-echo modulated small-angle neutron scattering (SEMSANS) as well as the potential combination with SANS. Based on the preliminary technical designs of SKADI (a SANS instrument proposed for the European Spallation Source) and a SEMSANS add-on, we assess the practicability, feasibility and scientific merit of a combined SANS and SEMSANS setup by calculating tentative SANS and SEMSANS results for soft matter, geology and advanced material samples that have been previously studied by scattering methods. We conclude that lengths from 1 nm up to 0.01 mm can be observed simultaneously in a single measurement. Thus, the combination of SANS and SEMSANS instrument is suited for the simultaneous observation of a wide range of length scales, e.g. for time-resolved studies of kinetic processes in complex multiscale systems.

Thermal neutron measurement using the instrumented test bundle and assessment of maximum linear power in HANARO

Energy Technology Data Exchange (ETDEWEB)

Lee, C. S.; Seo, C. K.; Lee, B. C.; Kim, H. N.; Kang, B. W. [KAERI, Taejon (Korea, Republic of)

2000-10-01

The HANARO fuel, U{sub 3}Si-Al, has been developed by AECL and tested in NRU reactor. Due to the lack of the data performed under the high power, the repetitive conduct of the irradiation test was required under the power greater than 108kW/m, which is the estimated maximum linear power in the design stage. Accordingly, the instrumented test bundle with SPND(Self Powered Neutron Detector) was fabricated and its irradiation test was performed in IR2 of HANARO. The measured thermal neutron flux with SPND is compared with calculation results by HANAFMS(HANARO Fuel Management System). The difference in the measured and calculated thermal flux values are below {+-}11% and the accuracy of the linear power predicted by HANAFMS is consequently accompanied. Therefore, it is believed that the maximum linear power above 120kW/m is achieved during the irradiation test of the test bundle.

Guidelines on calibration of neutron measuring devices

International Nuclear Information System (INIS)

Burger, G.

1988-01-01

The International Atomic Energy Agency and the World Health Organization have agreed to establish an IAEA/WHO Network of Secondary Standard Dosimetry Laboratories (SSDLs) in order to improve accuracy in applied radiation dosimetry throughout the world. These SSDLs must be equipped with, and maintain, secondary standard instruments, which have been calibrated against primary standards, and must be nominated by their governments for membership of the network. The majority of the existing SSDLs were established primarily to work with photon radiation (X-rays and gamma rays). Neutron sources are, however, increasingly being applied in industrial processes, research, nuclear power development and radiation biology and medicine. Thus, it is desirable that the SSDLs in countries using neutron sources on a regular basis should also fulfil the minimum requirements to calibrate neutron measuring devices. It is the primary purpose of this handbook to provide guidance on calibration of instruments for radiation protection. A calibration laboratory should also be in a position to calibrate instrumentation being used for the measurement of kerma and absorbed dose and their corresponding rates. This calibration is generally done with photons. In addition, since each neutron field is usually contaminated by photons produced in the source or by scatter in the surrounding media, neutron protection instrumentation has to be tested with respect to its intrinsic photon response. The laboratory will therefore need to possess equipment for photon calibration. This publication deals primarily with methods of applying radioactive neutron sources for calibration of instrumentation, and gives an indication of the space, manpower and facilities needed to fulfil the minimum requirements of a calibration laboratory for neutron work. It is intended to serve as a guide for centres about to start on neutron dosimetry standardization and calibration. 94 refs, 8 figs, 12 tabs

A new neutron counter for fission research

Energy Technology Data Exchange (ETDEWEB)

Laurent, B., E-mail: benoit.laurent@cea.fr [CEA, DAM, DIF, F-91297 Arpajon (France); Granier, T.; Bélier, G.; Chatillon, A.; Martin, J.-F.; Taieb, J. [CEA, DAM, DIF, F-91297 Arpajon (France); Hambsch, F.-J. [EC-JRC Institute for Reference Materials and Measurements (IRMM), Retieseweg, 2440 Geel (Belgium); Tovesson, F.; Laptev, A.B.; Haight, R.C.; Nelson, R.O.; O' Donnell, J.M. [Los Alamos Neutron Science Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2014-05-01

A new neutron counter for research experiments on nuclear fission has been developed. This instrument is designed for the detection of prompt fission neutrons within relatively high levels of gamma and neutron background. It is composed of a set of {sup 3}He proportional counters arranged within a block of polyethylene which serves as moderator. The detection properties have been studied by means of Monte Carlo simulations and experiments with radioactive sources. These properties are confirmed by an experiment on neutron-induced fission of {sup 238}U at the WNR facility of the Los Alamos Neutron Science Center during which the mean prompt fission neutron multiplicity, or ν{sup ¯} has been measured from 1 to 20 MeV of incident neutron energy.

Neutron CSI: Integrated platform for non-destructive composition and stress imaging with neutrons

International Nuclear Information System (INIS)

Materna, T.; Pirling, T.

2011-01-01

We propose to build an interdisciplinary platform for non-destructive analysis and imaging with neutrons. The project regroups an instrument already available at ILL (Laue-Langevin Institute), SALSA, with a new one for Neutron Tomography coupled to Prompt-Gamma Neutron Activation (PGNA) as well as partial usage of another proposed instrument, FIPPS. The focus of the proposition is the versatility of high spatial resolution and energy-selective neutron tomography to provide a rapid and precise 3D morphological map of an object as well as indirect information on its 3D elemental and structural composition through the scan of Bragg-edges in transmission. Coupled to PGNA imaging and the strain analysis power of SALSA, the aim of the platform is to answer key questions occurring in geological, metallurgical, engineering and medical fields, material research and cultural heritage. (authors)

An accurate and portable solid state neutron rem meter

Energy Technology Data Exchange (ETDEWEB)

Oakes, T.M. [Nuclear Science and Engineering Institute, University of Missouri, Columbia, MO (United States); Bellinger, S.L. [Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS (United States); Miller, W.H. [Nuclear Science and Engineering Institute, University of Missouri, Columbia, MO (United States); Missouri University Research Reactor, Columbia, MO (United States); Myers, E.R. [Department of Physics, University of Missouri, Kansas City, MO (United States); Fronk, R.G.; Cooper, B.W [Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS (United States); Sobering, T.J. [Electronics Design Laboratory, Kansas State University, KS (United States); Scott, P.R. [Department of Physics, University of Missouri, Kansas City, MO (United States); Ugorowski, P.; McGregor, D.S; Shultis, J.K. [Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS (United States); Caruso, A.N., E-mail: carusoan@umkc.edu [Department of Physics, University of Missouri, Kansas City, MO (United States)

2013-08-11

Accurately resolving the ambient neutron dose equivalent spanning the thermal to 15 MeV energy range with a single configuration and lightweight instrument is desirable. This paper presents the design of a portable, high intrinsic efficiency, and accurate neutron rem meter whose energy-dependent response is electronically adjusted to a chosen neutron dose equivalent standard. The instrument may be classified as a moderating type neutron spectrometer, based on an adaptation to the classical Bonner sphere and position sensitive long counter, which, simultaneously counts thermalized neutrons by high thermal efficiency solid state neutron detectors. The use of multiple detectors and moderator arranged along an axis of symmetry (e.g., long axis of a cylinder) with known neutron-slowing properties allows for the construction of a linear combination of responses that approximate the ambient neutron dose equivalent. Variations on the detector configuration are investigated via Monte Carlo N-Particle simulations to minimize the total instrument mass while maintaining acceptable response accuracy—a dose error less than 15% for bare {sup 252}Cf, bare AmBe, an epi-thermal and mixed monoenergetic sources is found at less than 4.5 kg moderator mass in all studied cases. A comparison of the energy dependent dose equivalent response and resultant energy dependent dose equivalent error of the present dosimeter to commercially-available portable rem meters and the prior art are presented. Finally, the present design is assessed by comparison of the simulated output resulting from applications of several known neutron sources and dose rates.

Neutron guides and scientific neutron equipment at CILAS/GMI

International Nuclear Information System (INIS)

Gautier-Picard, P.

2001-01-01

The French company CILAS is the world's leading supplier of complete neutron guide systems. The neutron optics with multilayer coatings produced by CILAS has become an international standard for neutron beam transportation at modern research institutes. During the last 30 years, CILAS designed, produced and installed more than 5000 meters of guides in many European, American and Asian countries. By these projects the company has acquired a very strong experience with: conception, design, manufacturing, setting up of Neutron Guides. In most cases, CILAS was in charge of the design, as well as the manufacturing of the whole system, comprising optical and mechanical components, vacuum system, shutter and shielding definition. By our long experience we have also acquired good knowledge of the materials used in this specific nuclear environment and their behavior under radiation such as glass, borated or not, coatings, glue or metal. To reinforce its leadership and presence in neutron research, CILAS acquired the company Grenoble Modular Instruments (GMI) a leading company in high precision mechanics, engineering and manufacturing of spectrometers and scientific equipment for neutron and synchrotron research. This merger allows us to design and to supply a complete range of high precision optical and mechanical eqipment for neutron research. CILAS and GMI have designed, manufactured and installed a High Resolution Powder Diffractometer for the 30MW Korean Hanaro Reactor. This project included the calculation, design and supply of the complete biological shielding of the instrument as well as for the primary beam shutter on the thermal beamport. (author)

The neutron beam facility at the Australian replacement research reactor

International Nuclear Information System (INIS)

Hunter, B.; Kennedy, S.

1999-01-01

Full text: The Australian federal government gave ANSTO final approval to build a research reactor to replace HIFAR on August 25th 1999. The replacement reactor is to be a multipurpose reactor with a thermal neutron flux of 3 x 10 14 n.cm -2 .s -1 and having improved capabilities for neutron beam research and for the production of radioisotopes for pharmaceutical, scientific and industrial use. The replacement reactor will commence operation in 2005 and will cater for Australian scientific, industrial and medical needs well into the 21st century. The scientific capabilities of the neutron beams at the replacement reactor are being developed in consultation with representatives from academia, industry and government research laboratories to provide a facility for condensed matter research in physics, chemistry, materials science, life sciences, engineering and earth sciences. Cold, thermal and hot neutron sources are to be installed, and neutron guides will be used to position most of the neutron beam instruments in a neutron guide hall outside the reactor confinement building. Eight instruments are planned for 2005, with a further three to be developed by 2010. A conceptual layout for the neutron beam facility is presented including the location of the planned suite of neutron beam instruments. The reactor and all the associated infrastructure, with the exception of the neutron beam instruments, is to be built by an accredited reactor builder in a turnkey contract. Tenders have been called for December 1999, with selection of contractor planned by June 2000. The neutron beam instruments will be developed by ANSTO and other contracted organisations in consultation with the user community and interested overseas scientists. The facility will be based, as far as possible, around a neutron guide hall that is be served by three thermal and three cold neutron guides. Efficient transportation of thermal and cold neutrons to the guide hall requires the use of modern super

In-pile Instrumentation Development

International Nuclear Information System (INIS)

Vermeeren, L.

2005-01-01

Advanced irradiations in research reactors require the on-line monitoring of crucial parameters like neutron fluxes, gamma dose rates, central fuel rod temperatures, fission gas release pressures and small geometry changes. Our activities in this field aim at a detailed understanding of the sensor behaviour in the irradiation conditions in order to extract reliable real-time information. The objectives of work performed by SCK-CEN are to study of the on-line in-pile measurement of gamma and neutron fluxes in real time and to investigate parasitic radiation-induced signals in instrumentation cables

Feasibility studies on large sample neutron activation analysis using a low power research reactor

International Nuclear Information System (INIS)

Gyampo, O.

2008-06-01

Instrumental neutron activation analysis (INAA) using Ghana Research Reactor-1 (GHARR-1) can be directly applied to samples with masses in grams. Samples weights were in the range of 0.5g to 5g. Therefore, the representativity of the sample is improved as well as sensitivity. Irradiation of samples was done using a low power research reactor. The correction for the neutron self-shielding within the sample is determined from measurement of the neutron flux depression just outside the sample. Correction for gamma ray self-attenuation in the sample was performed via linear attenuation coefficients derived from transmission measurements. Quantitative and qualitative analysis of data were done using gamma ray spectrometry (HPGe detector). The results of this study on the possibilities of large sample NAA using a miniature neutron source reactor (MNSR) show clearly that the Ghana Research Reactor-1 (GHARR-1) at the National Nuclear Research Institute (NNRI) can be used for sample analyses up to 5 grams (5g) using the pneumatic transfer systems.

Material science and neutron scattering

International Nuclear Information System (INIS)

1983-01-01

Neutron scattering experiments complete and extend the condensed matter studies made with X and gamma rays. Then story show a permanent evolution of the instrumentation, methods and experimental techniques to improve the result quality. This is more especially important as neutron sources are weaker than photon and electron sources. Progress in this research domain is due, in most part, to discovery and development of materials for the different measurement device components [fr

The new neutron radiography/tomography/imaging station DINGO at OPAL

International Nuclear Information System (INIS)

Garbe, U.; Randall, T.; Hughes, C.

2011-01-01

A new neutron imaging instrument will be built to support the area of neutron imaging research (neutron radiography/tomography) at ANSTO. The instrument will be designed for an international user community and for routine quality control for defence, industrial, mining, space and aircraft applications. It will also be a useful tool for assessing oil and water flow in sedimentary rock reservoirs (like the North West Shelf), assessing water damage in aircraft components, and the study of hydrogen distribution and cracking in steel. The instrument is planned to be completed by the end of June 2013 and is currently in the design stage. The usable neutron flux is mainly determined by the neutron source, but it also depends on the instrument position and the resolution. The designated instrument position for DINGO is the beam port HB-2 in the reactor hall. The estimated flux for an L/D of approximately 250 at HB-2 is calculated by Mcstas simulation in a range of 4.75x10 7 n/cm 2 s, which is in the same range of other facilities like ANSTARES (FRM II; Schillinger et al., 2004 ) or BT2 (NIST; Hussey et al., 2005 ). A special feature of DINGO is the in-pile collimator place in front of the main shutter at HB-2. The collimator offers two pinholes with a possible L/D of 250 and 1000. A secondary collimator will separate the two beams and block one. The whole instrument will operate in two different positions, one for high resolution and the other for high speed.

The new neutron radiography/tomography/imaging station DINGO at OPAL

Science.gov (United States)

Garbe, U.; Randall, T.; Hughes, C.

2011-09-01

A new neutron imaging instrument will be built to support the area of neutron imaging research (neutron radiography/tomography) at ANSTO. The instrument will be designed for an international user community and for routine quality control for defence, industrial, mining, space and aircraft applications. It will also be a useful tool for assessing oil and water flow in sedimentary rock reservoirs (like the North West Shelf), assessing water damage in aircraft components, and the study of hydrogen distribution and cracking in steel. The instrument is planned to be completed by the end of June 2013 and is currently in the design stage. The usable neutron flux is mainly determined by the neutron source, but it also depends on the instrument position and the resolution. The designated instrument position for DINGO is the beam port HB-2 in the reactor hall. The estimated flux for an L/ D of approximately 250 at HB-2 is calculated by Mcstas simulation in a range of 4.75×10 7 n/cm 2 s, which is in the same range of other facilities like ANSTARES (FRM II; Schillinger et al., 2004 [1]) or BT2 (NIST; Hussey et al., 2005 [2]). A special feature of DINGO is the in-pile collimator place in front of the main shutter at HB-2. The collimator offers two pinholes with a possible L/ D of 250 and 1000. A secondary collimator will separate the two beams and block one. The whole instrument will operate in two different positions, one for high resolution and the other for high speed.

Neutron irradiation facilities for fission and fusion reactor materials studies

International Nuclear Information System (INIS)

Rowcliffe, A.F.

1985-01-01

The successful development of energy-conversion machines based upon nuclear fission or fusion reactors is critically dependent upon the behavior of the engineering materials used to construct the full containment and primary heat extraction systems. The development of radiation damage-resistant materials requires irradiation testing facilities which reproduce, as closely as possible, the thermal and neutronic environment expected in a power-producing reactor. The Oak Ridge National Laboratory (ORNL) reference core design for the Center for Neutron Research (CNR) reactor provides for instrumented facilities in regions of both hard and mixed neutron spectra, with substantially higher fluxes than are currently available. The benefits of these new facilities to the development of radiation damage resistant materials are discussed in terms of the major US fission and fusion reactor programs

Responses of commercially available neutron electronic personal dosemeters in neutron fields simulating workplaces at MOX fuel fabrication facilities

International Nuclear Information System (INIS)

Tsujimura, N.; Yoshida, T.; Takada, C.

2011-01-01

The authors investigated the performance of three commercially available electronic personal dosemeters (EPDs) in evaluating neutron dose equivalents and discussed their suitability to work environments in MOX fuel fabrication facilities. The EPDs selected for this study were NRY21 (Fuji Electric Systems), PDM-313 (Aloka) and DMC 2000 GN (MGP Instruments). All tests were conducted in moderated 252 Cf neutron fields with neutron spectral and dosimetric characteristics similar to those found in MOX fuel facilities. The test results revealed trends and the magnitude of response variations in relation to neutron spectral changes expected in work environments.

Construction of the neutron beam facility at Australia's OPAL research reactor

International Nuclear Information System (INIS)

Kennedy, Shane J.

2006-01-01

Australia's new research reactor, OPAL, has been designed principally for neutron beam science and radioisotope production. It has a capacity for 18 neutron beam instruments, located at the reactor face and in a neutron guide hall. The neutron beam facility features a 20 l liquid deuterium cold neutron source and cold and thermal supermirror neutron guides. Nine neutron beam instruments are under development, of which seven are scheduled for completion in early 2007. The project is approaching the hot-commissioning stage, when criticality will be demonstrated. Installation of the neutron beam transport system and neutron beam instruments in the neutron guide hall and at the reactor face is underway, and the path to completion of this project is relatively clear. This paper will outline the key features of the OPAL reactor, and will describe the neutron beam facility in particular. The status of the construction and a forecast of the program to completion, including commissioning and commencement of routine operation in 2007 will also be discussed

A small angle neutron scattering study of thermoplastic elastomer

Energy Technology Data Exchange (ETDEWEB)

Sutiarso,; Edy Giri, R Putra; Andon, Insani; Sudirman,; Sudaryanto, [Materials Science Research Centre, National Atomic Energy Agency, Jakarta (Indonesia)

1998-10-01

A bilateral scientific cooperation, in the small angle neutron scattering has been agreed upon between CIAE, China and BATAN, Indonesia as well as MINT Malaysia. As stated in the agreed proposal that the objective of this cooperation, in the initial stage (stage-1), was to have a regional intercomparison measurements of SANS instruments in order to determine their characteristic/performance. Therefore, this report is supposed to describe the progress in the SANS instrument development of each country involved during the period of 1996/97 and some activities related to the SANS instrument. Since, up to now, we have not yet received any progresses reported from either China or Malaysia, this report will describe the progress of SANS`s activities in BATAN only. (author)

Geographic determination of the growing origins of Jamaican and international coffee using instrumental neutron activation analysis and other methods

International Nuclear Information System (INIS)

Antoine, J.M.R.; Hoo Fung, L.A.; Grant, Ch.N.

2016-01-01

This study was undertaken to determine whether elemental analysis could distinguish the growing origins of Jamaican versus international coffee and identify intra-island growing regions. Twenty-four samples of roasted and ground coffee and soluble coffee were collected and analysed using instrumental neutron activation analysis and inductively coupled plasma optical emission spectroscopy. Sixteen elements were selected for statistical evaluation. Soluble clustered discretely from roasted and ground samples. The distinction among roasted and ground samples was not as discrete. Geographic growing regions could be determined by statistical analysis; separating the growing sub-regions in Jamaica would require additional analyses. (author)

Very High Energy Neutron Scattering from Hydrogen

International Nuclear Information System (INIS)

Cowley, R A; Stock, C; Bennington, S M; Taylor, J; Gidopoulos, N I

2010-01-01

The neutron scattering from hydrogen in polythene has been measured with the direct time-of flight spectrometer, MARI, at the ISIS facility of the Rutherford Appleton Laboratory with incident neutron energies between 0.5 eV and 600 eV. The results of experiments using the spectrometer, VESUVIO, have given intensities from hydrogen containing materials that were about 60% of the intensity expected from hydrogen. Since VESUVIO is the only instrument in the world that routinely operates with incident neutron energies in the eV range we have chosen to measure the scattering from hydrogen at high incident neutron energies with a different type of instrument. The MARI, direct time-of-flight, instrument was chosen for the experiment and we have studied the scattering for several different incident neutron energies. We have learnt how to subtract the gamma ray background, how to calibrate the incident energy and how to convert the spectra to an energy plot . The intensity of the hydrogen scattering was independent of the scattering angle for scattering angles from about 5 degrees up to 70 degrees for at least 3 different incident neutron energies between 20 eV and 100 eV. When the data was put on an absolute scale, by measuring the scattering from 5 metal foils with known thicknesses under the same conditions we found that the absolute intensity of the scattering from the hydrogen was in agreement with that expected to an accuracy of ± 5.0% over a wide range of wave-vector transfers between 1 and 250 A -1 . These measurements show that it is possible to measure the neutron scattering with incident neutron energies up to at least 100 eV with a direct geometry time-of-flight spectrometer and that the results are in agreement with conventional scattering theory.

Neutron beam applications

International Nuclear Information System (INIS)

Lee, Chang Hee; Lee, J. S.; Seong, B. S.

2000-05-01

For the materials science by neutron technique, the development of the various complementary neutron beam facilities at horizontal beam port of HANARO and the techniques for measurement and analysis has been performed. High resolution powder diffractometer, after the installation and performance test, has been opened and used actively for crystal structure analysis, magnetic structure analysis, phase transition study, etc., since January 1998. The main components for four circle diffractometer were developed and, after performance test, it has been opened for crystal structure analysis and texture measurement since the end of 1999. For the small angle neutron spectrometer, the main component development and test, beam characterization, and the preliminary experiment for the structure study of polymer have been carried out. Neutron radiography facility, after the precise performance test, has been used for the non-destructive test of industrial component. Addition to the development of main instruments, for the effective utilization of those facilities, the scattering techniques relating to quantitative phase analysis, magnetic structure analysis, texture measurement, residual stress measurement, polymer study, etc, were developed. For the neutron radiography, photographing and printing technique on direct and indirect method was stabilized and the development for the real time image processing technique by neutron TV was carried out. The sample environment facilities for low and high temperature, magnetic field were also developed

Neutron-scattering studies of chromatin

International Nuclear Information System (INIS)

Bradbury, E.M.; Baldwin, J.P.; Carpenter, B.G.; Hjelm, R.P.; Hancock, R.; Ibel, K.

1976-01-01

It is clear that a knowledge of the basic molecular structure of chromatin is a prerequisite for any progress toward an understanding of chromosome organization. With a two-component system, protein and nucleic acid, neutrons have a particularly powerful application to studies of the spatial arrangements of these components because of the ability, by contrast matching with H 2 O-D 2 O mixtures, to obtain neutron-scattering data on the individual components. With this approach it has been shown that the neutron diffraction of chromatin is consistent with a ''beads on a string'' model in which the bead consists of a protein core with DNA coiled on the outside. However, because chromatin is a gel and gives limited structural data, confirmation of such a model requires extension of the neutron studies by deuteration of specific chromatin components and the isolation of chromatin subunits. Although these studies are not complete, the neutron results so far obtained support the subunit model described above

Neutron scattering studies in the actinide region

International Nuclear Information System (INIS)

Kegel, G.H.R.; Egan, J.J.

1993-09-01

This report discusses the following topics: Prompt fission neutron energy spectra for 235 U and 239 Pu; Two-parameter measurement of nuclear lifetimes; ''Black'' neutron detector; Data reduction techniques for neutron scattering experiments; Inelastic neutron scattering studies in 197 Au; Elastic and inelastic scattering studies in 239 Pu; and neutron induced defects in silicon dioxide MOS structures

The JET neutron emission profile monitor

International Nuclear Information System (INIS)

Adams, J.M.; Syme, D.B.; Watkins, N.; Jarvis, O.N.; Sadler, G.J.

1993-01-01

This paper provides a technical description of the neutron emission profile monitor as used routinely at the Joint European Torus (JET), and includes representative examples of its operational capabilities. The primary function of this instrument is to measure the neutron emission as a function of both position and time in a poloidal (vertical along major radius) section through the torus. For the first time the spatially localised effects of sawteeth (magnetic relaxation phenomena) have been observed using a neutron diagnostic. The total (global) neutron emission can be obtained from the profile monitor data by performing a volume integral over the plasma; the absolute neutron emission rates agree with those obtained from the JET time-resolved neutron monitor to within ±15%. This was the first such instrument routinely in use on any tokamak. It provides unique data which are independent of all other diagnostic measurements. (orig.)

Measuring the noble metal and iodine composition of extracted noble metal phase from spent nuclear fuel using instrumental neutron activation analysis

International Nuclear Information System (INIS)

Palomares, R.I.; Dayman, K.J.; Landsberger, S.; Biegalski, S.R.; Soderquist, C.Z.; Casella, A.J.; Brady Raap, M.C.; Schwantes, J.M.

2015-01-01

Masses of noble metal and iodine nuclides in the metallic noble metal phase extracted from spent fuel are measured using instrumental neutron activation analysis. Nuclide presence is predicted using fission yield analysis, and radionuclides are identified and the masses quantified using neutron activation analysis. The nuclide compositions of noble metal phase derived from two dissolution methods, UO 2 fuel dissolved in nitric acid and UO 2 fuel dissolved in ammonium-carbonate and hydrogen-peroxide solution, are compared. - Highlights: • The noble metal phase was chemically extracted from spent nuclear fuel and analyzed non-destructively. • Noble metal phase nuclides and long-lived iodine were identified and quantified using neutron activation analysis. • Activation to shorter-lived radionuclides allowed rapid analysis of long-lived fission products in spent fuel using gamma spectrometry