WorldWideScience

Sample records for californium 237

  1. Magnetism in californium

    International Nuclear Information System (INIS)

    Moore, J.R.

    1988-03-01

    A SQUID-based magnetic susceptometer has been constructed for studying small radioactive samples at temperatures below 350 K and in magnetic fields up to 50 kilogauss. The device has been used to study californium (element 98) in a number of solid-state forms: the dhcp metal, several oxides (Cf 2 O 3 in both the bcc and monoclinic structures, Cf 7 O 12 , CfO 2 and BaCfO 3 ), several monopnictides (CfN, CfAs and CfSb) and the trichloride (in both the hexagonal and orthorhombic structures). All of these materials were studied in polycrystalline form, and hexagonal CfCl 3 was studied in single-crystal form as well. The susceptometer has the sensitivity to measure samples containing less than 10 micrograms of californium. The magnetic susceptibilities of all of the californium materials at temperatures above about 100 K are described well by the Curie-Weiss relationship. This behavior is consistent with the assumption that the magnetic 5f electrons are localized and that the paramagnetic behavior can be interpreted in terms of the properties of the free ion. The measured values of the effective paramagnetic moment, μ/sub eff/, for all the californium materials that were studied are reasonably consistent with theoretical values based on intermediate coupling models. All of the californium materials showed some indications of cooperative magnetic effects. The dhcp metal was observed to order ferromagnetically at 52 K, and all of the californium compounds studied showed signs of antiferromagnetic ordering, mostly at temperatures below 25 K. 91 refs., 50 figs., 19 tabs

  2. Medical applications of californium-252

    International Nuclear Information System (INIS)

    Oliver, G.D. Jr.

    1975-01-01

    Primarily, californium-252 sources have been utilized in medicine for the treatment of neoplastic lesions. For five years, a coordinated effort between several cancer research institutions and national laboratories has developed the necessary physics, radiobiology, and engineering skills to establish an evaluation program for californium. Several more years of combined effort are required before it is known whether californium therapy is as good as or better than conventional therapy with sources like radium. Recently, development of diagnostic applications of californium in medicine has received attention. Studies comparing neutron decay activation analysis versus prompt capture gamma ray analysis are in progress. A hopeful application of prompt analysis with reasonable quantities (200 μg) of californium is the elemental analysis of bone in the human body. (U.S.)

  3. Californium-252 progress, report No. 7, April 1971

    Energy Technology Data Exchange (ETDEWEB)

    1971-12-31

    This report contains discusses of the following topics on Californium-252: First sales of californium-252; encapsulation services discussed; three new participants in market evaluation program; summer training programs to use californium; Californium-252 shipping casks available; Californium-252 questions and answers, radiotherapy; neutron radiography; natural resources exploration; nuclear safeguards; process control; dosimetry; neutron radiography; neutron shielding; and nuclear safeguards.

  4. Radiography using californium-252 neutron sources

    International Nuclear Information System (INIS)

    Ray, J.W.

    1975-01-01

    The current status in the technology of neutron radiography using californium-252 neutron sources is summarized. Major emphasis is on thermal neutron radiography since it has the widest potential applicability at the present time. Attention is given to four major factors which affect the quality and useability of thermal neutron radiography: source neutron thermalization, neutron beam extraction geometry, neutron collimator dimensions, and neutron imaging methods. Each of these factors has a major effect on the quality of the radiographs which are obtained from a californium source neutron radiography system and the exposure times required to obtain the radiographs; radiograph quality and exposure time in turn affect the practicality of neutron radiography for specific nondestructive inspection applications. A brief discussion of fast neutron radiography using californium-252 neutron sources is also included. (U.S.)

  5. Historical review of californium-252 discovery and development

    International Nuclear Information System (INIS)

    Stoddard, D.H.

    1985-01-01

    This paper discusses the discovery and history of californium 252. This isotope may be synthesized by irradiating plutonium 239, plutonium 242, americium 243, or curium 244 with neutrons in a nuclear reactor. Various experiments and inventions involving 252 Cf conducted at the Savannah River Plant are discussed. The evolution of radiotherapy using californium 252 is reviewed

  6. Californium-252 sales and loans at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    King, L.J.

    1987-01-01

    The production and distribution in the United States of 252 Cf has recently been consolidated at the Oak Ridge National Laboratory (ORNL). The 252 Cf Industrial Sales/Loan Program and the 252 Cf University Load Program, which were formerly located at the Savannah River Plant (SRP), have been combined with the californium production and distribution activities of the Transuranium Element Production Program at ORNL. Californium-252 is sold to commercial users in the form of bulk californium oxide, palladium-californium alloy pellets, or alloy wires. Neutron source capsules, which are fabricated for loans to DOE or other US government agencies, are still available in all forms previously available. The consolidation of all 252 Cf distribution activities at the production site is expected to result in better service to users. In particular, customers for neutrons sources will be ale to select from a wider range of neutron source forms, including custom designs, through a single contact point

  7. Fabrication of californium-252 sources in the United Kingdom

    International Nuclear Information System (INIS)

    Ainsworth, A.; Brady, M.W.; Thornett, W.H.

    1975-01-01

    The advent of californium-252 in weighable quantities and at a reasonable price has caused some rethinking among neutron source suppliers. To explore this market the Radiochemical Center Ltd. has purchased 2 mg of californium-252, and subdivided this into a wide range of sources. To take advantage of its high specific neutron emission, a small double welded stainless steel capsule 7.8mm diameter x 10mm high was chosen for stock sources and this entailed the use of a microdispensing technique which had to be specially developed. The apparatus and procedure for subdividing milligram amounts of californium-252 are described. Some details of our experience in processing these one milligram shipments are given. 100 sources with activities from 200 microgram to 0.01 microgram have been produced. Losses have been small. Measurement of neutron spectra gamma spectra and dose rates from encapsulated sources has confirmed published data. Though it is early days, little industrial interest in californium-252 sources has been detected, most of the sources have so far been required for research into activation analysis and two examples of this are given. (U.S.)

  8. Biomedical neutron research at the Californium User Facility for neutron science

    International Nuclear Information System (INIS)

    Martin, R.C.; Byrne, T.E.; Miller, L.F.

    1997-01-01

    The Californium User Facility for Neutron Science has been established at Oak Ridge National Laboratory (ORNL). The Californium User Facility (CUF) is a part of the larger Californium Facility, which fabricates and stores compact 252 Cf neutron sources for worldwide distribution. The CUF can provide a cost-effective option for research with 252 Cf sources. Three projects at the CUF that demonstrate the versatility of 252 Cf for biological and biomedical neutron-based research are described: future establishment of a 252 Cf-based neutron activation analysis system, ongoing work to produce miniature high-intensity, remotely afterloaded 252 Cf sources for tumor therapy, and a recent experiment that irradiated living human lung cancer cells impregnated with experimental boron compounds to test their effectiveness for boron neutron capture therapy

  9. Biomedical neutron research at the Californium User Facility for Neutron Science

    International Nuclear Information System (INIS)

    Martin, R.C.; Byrne, T.E.; Miller, L.F.

    1998-01-01

    The Californium User Facility for Neutron Science has been established at Oak Ridge National Laboratory (ORNL). The Californium User Facility (CUF) is a part of the larger Californium Facility, which fabricates and stores compact 252 Cf neutron sources for worldwide distribution. The CUF can provide a cost-effective option for research with 252 Cf sources. Three projects at the CUF that demonstrate the versatility of 252 Cf for biological and biomedical neutron-based research are described: future establishment of a 252 Cf-based neutron activation analysis system, ongoing work to produce miniature high-intensity, remotely afterloaded 252 Cf sources for tumor therapy, and a recent experiment that irradiated living human lung cancer cells impregnated with experimental boron compounds to test their effectiveness for boron neutron capture therapy. (author)

  10. Californium Multiplier. Part I. Design for neutron radiography

    International Nuclear Information System (INIS)

    Crosbie, K.L.; Preskitt, C.A.; John, J.; Hastings, J.D.

    1982-01-01

    The Californium Multiplier (CFX) is a subcritical assembly of enriched uranium surrounding a californium-252 neutron source. The function of the CFX is to multiply the neutrons emitted by the source to a number sufficient for neutron radiography. The CFX is designed to provide a collimated beam of thermal neutrons from which the gamma radiation is filtered, and the scattered neutrons are reduced to make it suitable for high resolution radiography. The entire system has inherent safety features, which provide for system and personnel safety, and it operates at moderate cost. In Part I, the CFX and the theory of its operation are described in detail. Part II covers the performance of the Mound Facility CFX

  11. Californium-252 radiotherapy sources for interstitial afterloading

    International Nuclear Information System (INIS)

    Permar, P.H.; Walker, V.W.

    1976-01-01

    Californium-252 neutron sources for interstitial afterloading were developed to investigate the value of this radionuclide in cancer therapy. Californium-252 seed assemblies contain essentially point sources of 252 Cf permanently sealed on 1-cm centers within a flexible plastic tube. The seed assemblies are fabricated with remotely operated, specially designed machines. The fabrication process involves the production of a Pt-10 percent Ir-clad wire with a 252 Cf 2 O 3 -Pd cermet core. The wire is swaged and drawn to size, cut to length, and welded in a Pt-10 percent Ir capsule 0.8 mm in diameter and 6 mm long. Each seed capsule contains approximately 0.5 microgram of 252 Cf. Because the effective half-life of 252 Cf is 2.6 years, the seed assemblies are not disposable and must be reused until their activities have decreased to unsuitable levels. The flexible plastic components must therefore have sufficient resistance to radiation damage to survive the neutron-plus-gamma radiation from 252 Cf. On the basis of accelerated irradiation tests with a large 252 Cf source, a recently developed fluoropolymer, ''Tefzel'' (trademark of E. I. du Pont de Nemours and Company) has adequate radiation resistance for this application. Californium-252 seed assembly systems are loaned by the United States Energy Research and Development Administration for clinical investigations under a protocol of the Radiation Therapy Oncology Group, U.S. National Cancer Institute

  12. Uranium standards for Californium Shuffler

    International Nuclear Information System (INIS)

    Gibbs, A.; Boynton, S.P.

    1978-10-01

    The Laboratories Department analyzed pieces of a U-Al log which were to be canned and used as a set of standards for the nondestructive Californium Shuffler instrument. Evaluation of this instrument is part of an on-going Safeguards Program and is a joint project between LASL and SRP. A U-Al casting of a nominal 30% to 70% composition was made with enriched uranium (56 wt % 235 U). The log was 6 in. in diameter and approximately 2 ft long. A 1/4-in. slice was made before and after each 1-in. slice taken for use as a standard. The 1-in. slices were scanned nondestructively by collimated gamma pulse height analysis. The 1/4-in. slices were divided into quadrants and one quadrant for each slice was destructively analyzed. Results from these tests showed an approximate 1.5% relative variation in uranium concentration from the high to the low point. Successive pieces showed less than 1% relative difference. The 1-in. pieces have been canned and shipped to LASL for testing and will be returned with the Californium Shuffler. The remaining 1/4-in. slices have been sent to NBL and LASL for destructive analysis

  13. Californium-252: a remarkable versatile radioisotope

    International Nuclear Information System (INIS)

    Osborne-Lee, I.W.; Alexander, C.W.

    1995-01-01

    A product of the nuclear age, Californium-252 ( 252 Cf) has found many applications in medicine, scientific research, industry, and nuclear science education. Californium-252 is unique as a neutron source in that it provides a highly concentrated flux and extremely reliable neutron spectrum from a very small assembly. During the past 40 years, 252 Cf has been applied with great success to cancer therapy, neutron radiography of objects ranging from flowers to entire aircraft, startup sources for nuclear reactors, fission activation for quality analysis of all commercial nuclear fuel, and many other beneficial uses, some of which are now ready for further growth. Californium-252 is produced in the High Flux Isotope Reactor (HFIR) and processed in the Radiochemical Engineering Development Center (REDC), both of which are located at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The REDC/HFIR facility is virtually the sole supplier of 252 Cf in the western world and is the major supplier worldwide. Extensive exploitation of this product was made possible through the 252 Cf Market Evaluation Program, sponsored by the United States Department of Energy (DOE) [then the Atomic Energy Commission (AEC) and later the Energy Research and Development Administration (ERDA)]. This program included training series, demonstration centers, seminars, and a liberal loan policy for fabricated sources. The Market Evaluation Program was instituted, in part, to determine if large-quantity production capability was required at the Savannah River Laboratory (SRL). Because of the nature of the product and the means by which it is produced, 252 Cf can be produced only in government-owned facilities. It is evident at this time that the Oak Ridge research facility can meet present and projected near-term requirements. The production, shipment, and sales history of 252 Cf from ORNL is summarized herein

  14. Californium-252: a remarkable versatile radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Osborne-Lee, I.W.; Alexander, C.W.

    1995-10-10

    A product of the nuclear age, Californium-252 ({sup 252}Cf) has found many applications in medicine, scientific research, industry, and nuclear science education. Californium-252 is unique as a neutron source in that it provides a highly concentrated flux and extremely reliable neutron spectrum from a very small assembly. During the past 40 years, {sup 252}Cf has been applied with great success to cancer therapy, neutron radiography of objects ranging from flowers to entire aircraft, startup sources for nuclear reactors, fission activation for quality analysis of all commercial nuclear fuel, and many other beneficial uses, some of which are now ready for further growth. Californium-252 is produced in the High Flux Isotope Reactor (HFIR) and processed in the Radiochemical Engineering Development Center (REDC), both of which are located at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The REDC/HFIR facility is virtually the sole supplier of {sup 252}Cf in the western world and is the major supplier worldwide. Extensive exploitation of this product was made possible through the {sup 252}Cf Market Evaluation Program, sponsored by the United States Department of Energy (DOE) [then the Atomic Energy Commission (AEC) and later the Energy Research and Development Administration (ERDA)]. This program included training series, demonstration centers, seminars, and a liberal loan policy for fabricated sources. The Market Evaluation Program was instituted, in part, to determine if large-quantity production capability was required at the Savannah River Laboratory (SRL). Because of the nature of the product and the means by which it is produced, {sup 252}Cf can be produced only in government-owned facilities. It is evident at this time that the Oak Ridge research facility can meet present and projected near-term requirements. The production, shipment, and sales history of {sup 252}Cf from ORNL is summarized herein.

  15. Local Structure in Americium and Californium Hexa-cyanoferrates - Comparison with Their Lanthanide Analogues

    International Nuclear Information System (INIS)

    Dupouy, G.; Bonhoure, I.; Dumas, Th.; Moisy, Ph.; Petit, S.; Den Auwer, Ch.; Conradson, St.D.; Hennig, Ch.; Scheinost, A.C.; Le Naour, C.; Simoni, E.

    2011-01-01

    Metal hexa-cyanoferrates are well known molecular solids for a large variety of cations, although very little has been described for actinide adducts. Two new members of actinide(III) hexa-cyanoferrates were synthesized with the cations americium and californium. They were structurally characterized by infrared and X-ray absorption spectroscopy. Combined EXAFS data at the iron K edge and actinide L 3 edge provide evidence for a three-dimensional model for these two new compounds. Structural data in terms of bond lengths were compared to those reported for the parent lanthanide(III) compounds, neodymium and gadolinium hexa-cyanoferrates, respectively: the americium compound with (KNd(III)Fe(II)-Fe-III(CN) 6 .4H 2 O and the californium compound with (KGd(III)Fe(II)(CN) . 3.5H 2 O and (KGd(III)Fe(II)(CN) 6 .3H 2 O. This comparison between actinide and lanthanide homologues has been carried out on the basis of ionic radii considerations. The americium and neodymium environments appear to be very similar and are arranged in a tri-capped trigonal prism polyhedron of coordination number 9 (CN: 9), in which the americium atom is bonded to six nitrogen atoms and to three water molecules. For the californium adduct, a similar comparison and bond length and angle values derived from EXAFS studies suggest that the californium cation sits in a bi-capped trigonal prism (CN: 8) as in (KGd(III)Fe(II)(CN) 6 . 3H 2 O. This arrangement differs from that in the structure of (KGd(III)Fe(II)(CN) 6 .3.5H 2 O, in which the gadolinium atom is surrounded by 9 atoms. This is one of the rare pieces of information revealed by EXAFS spectroscopy for americium and californium in comparison to lanthanide atoms in molecular solid compounds. A discussion on the decrease in bond length and coordination number from americium to californium is also provided, on the basis of crystallographic results reported in the literature for actinide(III) and lanthanide(III) hydrate series. (authors)

  16. Proposed Californium-252 User Facility for Neutron Science at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Martin, R.C.; Laxson, R.R.; Knauer, J.B.

    1996-01-01

    The Radiochemical Engineering Development Center (REDC) at ORNL has petitioned to establish a Californium-252 User Facility for Neutron Science for academic, industrial, and governmental researchers. The REDC Californium Facility (CF) stores the national inventory of sealed 252 Cf neutron source for university and research loans. Within the CF, the 252 Cf storage pool and two uncontaminated hot cells currently in service for the Californium Program will form the physical basis for the User Facility. Relevant applications include dosimetry and experiments for neutron tumor therapy; fast and thermal neutron activation analysis of materials; experimental configurations for prompt gamma neutron activation analysis; neutron shielding and material damage studies; and hardness testing of radiation detectors, cameras, and electronics. A formal User Facility simplifies working arrangements and agreements between US DOE facilities, academia, and commercial interests

  17. Californium loan programme

    International Nuclear Information System (INIS)

    1974-01-01

    The offer of the United States to loan Californium-252 sources to the IAEA was made by Dr. Glenn T. Seaborg, then chairman of the USAEC, in his opening statement at the 15th. General Conference of the IAEA held in Vienna in 1971. The purpose of this loan was to make neutron emitting sources available to universities in the Member States for use in educational programmes. The sources, in the form of small needles designed for medical use in radiation therapy, were judged highly suitable for didactic applications due to their small size, limited activity and well documented radiological parameters. Subsequently, in May 1973, the Director General announced the availability of the Californium sources to the Member States. To date, numerous sources have been loaned to universities in Czechoslovakia, Costa Rica, the Federal Republic of Germany, Ghana, India, Iran, Israel, Japan, South Africa, Switzerland, the United Kingdom and Uruguay; additional applications for loans are being processed. It is anticipated that the loan programme will be terminated in 1975 once all the available sources have been distributed. n order to provide guidance for the Member States on the safe exploitation of these sources, a prototype use and storage facility was designed by IAEA staff of the Dosimetry Section of the Division of Life Sciences, and constructed at the IAEA laboratory in Seibersdorf, Austria. Figures 2-5 illustrate some of the details of this container, which is being given to the Ghana Nuclear Centre in support of a training programme for students at the university in Accra. Further advice to users of these sources will be provided by the publication of an instructional syllabus, a laboratory manual for experiments and the safety precautions inherent in the proper handling of neutron emitting radionuclides, authored by Professors Erich J. Hall and Harald H. Rossi of Columbia University. The syllabus and manual will be published as part of the IAEA Technical Series in September

  18. Production, Distribution, and Applications of Californium-252 Neutron Sources

    International Nuclear Information System (INIS)

    Balo, P.A.; Knauer, J.B.; Martin, R.C.

    1999-01-01

    The radioisotope 252 Cf is routinely encapsulated into compact, portable, intense neutron sources with a 2.6-year half-life. A source the size of a person's little finger can emit up to 10 11 neutrons/s. Californium-252 is used commercially as a reliable, cost-effective neutron source for prompt gamma neutron activation analysis (PGNAA) of coal, cement, and minerals, as well as for detection and identification of explosives, laud mines, and unexploded military ordnance. Other uses are neutron radiography, nuclear waste assays, reactor start-up sources, calibration standards, and cancer therapy. The inherent safety of source encapsulations is demonstrated by 30 years of experience and by U.S. Bureau of Mines tests of source survivability during explosions. The production and distribution center for the U. S Department of Energy (DOE) Californium Program is the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL). DOE sells 252 Cf to commercial reencapsulators domestically and internationally. Sealed 252 Cf sources are also available for loan to agencies and subcontractors of the U.S. government and to universities for educational, research, and medical applications. The REDC has established the Californium User Facility (CUF) for Neutron Science to make its large inventory of 252 Cf sources available to researchers for irradiations inside uncontaminated hot cells. Experiments at the CUF include a land mine detection system, neutron damage testing of solid-state detectors, irradiation of human cancer cells for boron neutron capture therapy experiments, and irradiation of rice to induce genetic mutations

  19. Californium source transfer

    International Nuclear Information System (INIS)

    Wallace, C.R.

    1995-01-01

    In early 1995, the receipt of four sealed californium-252 sources from Oak Ridge National Lab was successfully accomplished by a team comprised of Radiological Engineering, Radiological Operations and Health Physics Instrumentation personnel. A procedure was developed and walked-down by the participants during a Dry Run Evolution. Several special tools were developed during the pre-planning phases of the project which reduced individual and job dose to minimal levels. These included a mobile lifting device for attachment of a transfer ball valve assembly to the undercarriage of the Cannonball Carrier, a transfer tube elbow to ensure proper angle of the source transfer tube, and several tools used during emergency response for remote retrieval and handling of an unshielded source. Lessons were learned in the areas of contamination control, emergency preparedness, and benefits of thorough pre-planning, effectiveness of locally creating and designing special tools to reduce worker dose, and methods of successfully accomplishing source receipt evolutions during extreme or inclement weather

  20. Spectroscopic and redox properties of curium and californium ions in concentrated aqueous carbonate-bicarbonate media

    International Nuclear Information System (INIS)

    Hobart, D.E.; Varlashkin, P.G.; Samhoun, K.; Haire, R.G.; Peterson, J.R.

    1983-01-01

    Multimilligram quantities of trivalent curium-248 and californium-249 were investigated by absorption spectroscopy, cyclic voltammetry, and bulk solution electrolysis in concentrated aqueous carbonate-bicarbonate solution. Actinide concentrations between 10 -4 and 10 -2 M were studied in 2 M sodium carbonate and 5.5 M potassium carbonate solutions at pH values from 8 to 14. The solution absorption spectra of Cm(III) and Cf(III) in carbonate media are presented for the first time and compared to literature spectra of these species in noncomplexing aqueous solution. It was anticipated that carbonate complexation of the actinide ions could provide a sufficient negative shift in the formal potentials of the M(IV)/M(III) couples of Cm and Cf to permit the generation and stabilization of their tetravalent states in aqueous carbonate-bicarbonate medium. No conclusive evidence was found in the present work to indicate the existence of any higher oxidation states of curium or californium in carbonate solution. Some possible reasons for our inability to generate and detect oxidized species of curium and californium in this medium are discussed

  1. Californium-252

    International Nuclear Information System (INIS)

    1975-01-01

    This meeting constituted the third phase of a project initiated by the Dosimetry Section of the IAEA in 1973. The first step, early in 1973, consisted of the development of a programme for the loan of Cf-252 sources to the Member States in support of education, training and some limited research. To date, 14 institutions in 13 Member States have participated in this loan programme. In August last year, the Agency published an instructional syllabus and laboratory manual authored by Professors Eric J. Hall and Harald H. Rossi of Columbia University (Californium-252 in Teaching and Research, Technical Reports Series No. 159). The appearance of this publication, including guidance on the design and construction of a storage and use facility, was the second phase of this programme aimed at providing some support to potential users in the fields of radiation biology and dosimetry. The objective of the programme's third phase - the convening of an Educational Seminar - was to provide a forum to bring together participants in the Agency's loan programme and experts in various scientific fields. Specifically, the Seminar consisted of a series of expert presentations in spectrometry, activation and prompt gamma analyses, on-stream analysis, dosimetry, health physics, radiology and radiotherapy. (author)

  2. X-ray-diffraction study of californium metal to 16 GPa

    International Nuclear Information System (INIS)

    Peterson, J.R.; Benedict, U.; Dufour, C.; Birkel, I.; Haire, R.G.

    1983-01-01

    The first series of measurements to determine the structural behavior of californium (Cf) metal under pressure has been carried out. The initial dhcp structure transformed sluggishly with increasing pressure to a fcc structure. A bulk modulus of 50(5) GPa was derived for dhcp Cf metal from the relative volume (V/V 0 ) data to 10 GPa

  3. Study of the shielding for spontaneous fission sources of Californium-252

    International Nuclear Information System (INIS)

    Davila R, I.

    1991-06-01

    A shielding study is made to attenuate, until maximum permissible levels, the neutrons radiation and photons emitted by spontaneous fission coming from a source of Californium-252. The compound package by a database (Library DLC-23) and the ANISNW code is used, in it version for personal computer. (Author)

  4. Convenient method of simultaneously analyzing aluminum and magnesium in pharmaceutical dosage forms using californium-252 thermal neutron activation

    International Nuclear Information System (INIS)

    Landolt, R.R.; Hem, S.L.

    1983-01-01

    A commercial antacid suspension containing aluminum hydroxide and magnesium hydroxide products was used as a model sample to study the use of a californium-252 thermal neutron activation as a method for quantifying aluminum content as well as for the simultaneous assay of aluminum and magnesium. A 3.5-micrograms californium-252 source was used for the activation, and the induced aluminum-28 and magnesium-27 activity was simultaneously measured by sodium iodide crystal gamma-ray spectrometry using dual single-channel analyzers and scalers. The antacid suspension was contained in a chamber designed with the unique capability of serving as the container for counting the induced radioactivity in addition to being the irradiation chamber itself. This pilot study demonstrated that use of more intense californium-252 sources, which are commonly available, would provide a method that is competitive with the ethylenediaminetetraacetic acid titration method in precision and in other aspects as well

  5. Atlantic Richfield Hanford Company californium multiplier/delayed neutron counter safety analysis

    International Nuclear Information System (INIS)

    Zimmer, W.H.

    1976-08-01

    The Californium Multiplier (CFX) is a subcritical assembly of uranium surrounding 252 Cf spontaneously fissioning neutron sources; its function is to multiply the neutron flux to a level useful for activation analysis. This document summarizes the safety analysis aspects of the CFX, DNC, pneumatic transfer system, and instrumentation and to detail all the aspects of the total facility as a starting point for the ARHCO Safety Analysis Review. Recognized hazards and steps already taken to neutralize them are itemized

  6. Californium oxygen system for 1.50 < O/Cf < 1.72

    International Nuclear Information System (INIS)

    Turcotte, R.P.; Haire, R.G.

    1975-01-01

    The californium-oxygen system was studied as a function of temperature, oxygen pressure, and stoichiometry by manometric and x-ray diffraction methods. The results establish rhombohedral Cf 7 O 12 as the stable compound obtained by heating Cf 2 O 3 in air. The isobaric oxidation-reduction cycles Cf 2 O 3 → Cf 7 O 12 → Cf 2 O 3 , observed in constant rate of heating (cooling) experiments, occur with large hysteresis. A close parallel to other fluorite related lanthanide and actinide oxide systems is established. (auth)

  7. 49 CFR 237.131 - Design.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Design. 237.131 Section 237.131 Transportation... TRANSPORTATION BRIDGE SAFETY STANDARDS Repair and Modification of Bridges § 237.131 Design. Each repair or... component of a bridge shall be designed by a railroad bridge engineer. The design shall specify the manner...

  8. Assessment of the neutron component in a neutron-gamma field of a californium-252 source

    International Nuclear Information System (INIS)

    Tetteh, G.K.

    1978-12-01

    Experiments have been performed to determine the percentages of the different components in the radiation field of californium-252 which has now some clinical applications. Using Rossi Chambers in conjunction with absorption investigations involving lead and aluminium thimbles, it is observed that the dose rates due to the different components are: neutrons 54%; gammas 30%; betas 16%

  9. Analysis list: nhr-237 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available nhr-237 Embryo,Larvae + ce10 http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target.../nhr-237.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/nhr-237.5.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/ce10/target/nhr-237.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/nhr-237.E...mbryo.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/nhr-237.Larvae.tsv http://dbarchive.bioscie...ncedbc.jp/kyushu-u/ce10/colo/Embryo.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/Larvae.gml ...

  10. 49 CFR 238.237 - Automated monitoring.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Automated monitoring. 238.237 Section 238.237 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Equipment § 238.237 Automated monitoring. (a) Except as further specified in this paragraph, on or after...

  11. Measurements of integral cross sections in the californium-252 fission neutron spectrum

    International Nuclear Information System (INIS)

    Alberts, W.G.; Guenther, E.; Matzke, M.; Rassl, G.

    1977-01-01

    In a low-scattering arrangement cross sections averaged over the californium-252 spontaneous fission neutron spectrum were measured. The reactions 27 Al(n,α) 46 Ti, 47 Ti, 48 Ti(n,p), 54 Fe, 56 Fe(n,p), 58 Ni(n,p), 64 Zn(n,p), 115 In(n,n') were studied in order to obtain a consistent set of threshold detectors used in fast neutron flux density measurements. Overall uncertainties between 2 and 2.5% could be achieved; corrections due to neutron scattering in source and samples are discussed

  12. 47 CFR 24.237 - Interference protection.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Interference protection. 24.237 Section 24.237... SERVICES Broadband PCS § 24.237 Interference protection. (a) All licensees are required to coordinate their... protection criterion shall be such that the interfering signal will not produce more than 1.0 dB degradation...

  13. 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)

  14. Neutron reflector design with Californium 252 neutron for Boron neutron chapter therapy facility using MCNP5 simulation method

    International Nuclear Information System (INIS)

    Muhammad Fakhrurreza; Kusminanto; Y Sardjono

    2014-01-01

    In this research has made a reflector design to provide beams of Neutron for BNCT with Californium-252 radioactive source. This collimator is useful to obtain optimum epithermal neutron flux with the smallest impurity radiation (thermal neutron, fast neutron, and gamma). The design process is done using Monte Carlo N-Particle simulation version 5 (MCNP5) code to calculate the neutron flux tally form. The chosen reflector design is the reflectors which use material such as BeO ceramic with 13 cm thick. Moderator use sulfur material with the slope angle of the cone is 30°. From the calculation result, it is obtained that Reflector with 1 gram Californium-252 source can produce a neutron output thermal which has thermal neutron specification 2.23189 x 10 9 n/s.cm 2 , epithermal neutron 3.51548 x 10 9 n/s.cm 2 , and fast neutron 4.82241 x 10 9 n/s.cm 2 From the result, it needs additional collimator because the BNCT requirement. (author)

  15. Calibration of a Modified Californium Shuffler

    International Nuclear Information System (INIS)

    Sadowski, E.T.; Armstrong, F.; Oldham, R.; Ceo, R.; Williams, N.

    1995-01-01

    A californium shuffler originally designed to assay hollow cylindrical pieces of UA1 has been modified to assay solid cylinders. Calibration standards were characterized via chemical analysis of the molten UA1 taken during casting of the standards. The melt samples yielded much more reliable characterization data than drill samples taken from standards after the standards had solidified. By normalizing one well-characterized calibration curve to several standards at different enrichments, a relatively small number of standards was required to develop an enrichment-dependent calibration. The precision of this shuffler is 0.65%, and the typical random and systematic uncertainties are 0.53% and 0.73%, respectively, for a six minute assay of an ingot containing approximately 700 grams of 235 U. This paper will discuss (1) the discrepancies encountered when UA1 standards were characterized via melt samples versus drill samples, (2) a calibration methodology employing a small number of standards, and (3) a comparison of results from a previously unused shuffler with an existing shuffler. A small number of UA1 standards have been characterized using samples from the homogeneous molten state and have yielded enrichment-dependent and enrichment-independent calibration curves on two different shufflers

  16. Prompt neutron spectrum of the spontaneous fission of californium-252

    International Nuclear Information System (INIS)

    Zamyatnin, Yu.S.; Kroshkin, N.I.; Korostylev, V.A.; Nefedov, V.N.; Ryazanov, D.K.; Starostov, B.I.; Semenov, A.F.

    1976-01-01

    The californium-252 spontaneous fission neutron spectrum was measured in the energy range of 0.01 to 10 MeV by the time-of-flight technique using various neutron detectors. The measurements of 252 Cf neutron spectrum at energies of 0.01 to 5 MeV were performed as a function of fission fragment kinetic energy. The mean neutron spectrum energy in the range of 0.7 to 10 MeV was found from the results of measurements. The irregularity in the 252 Cf neutron spectrum in the neutron energy range of less than 0.7 MeV compared to theoretical values is discussed. The mechanism of 252 Cf neutron emission is also discussed on the basis of neutron yield angle measurements. 12 references

  17. Criticality of a 237Np sphere

    International Nuclear Information System (INIS)

    Sanchez, Rene G.; Loaiza, David J.; Kimpland, Robert H.; Hayes, David K.; Cappiello, Charlene C.; Myers, William L.; Jaegers, Peter J.; Clement, Steven D.; Butterfield, Kenneth B.

    2003-01-01

    A critical mass experiment using a 6-kg 237 Np sphere has been performed. The purpose of the experiment is to get a better estimate of the critical mass of 237 Np. To attain criticality, the 237 Np sphere was surrounded with 93 wt% 235 U shells. A 1/M as a function of uranium mass was performed. An MCNP neutron transport code was used to model the experiment. The MCNP code yielded a k eff of 0.99089 ± 0.0003 compared with a k eff 1.0026 for the experiment. Based on these results, it is estimated that the critical mass of 237 Np ranges from kilogram weights in the high fifties to low sixties. (author)

  18. Safety Analysis Report for Packaging (SARP) of the Oak Ridge National Laboratory TRU Californium Shipping Container

    International Nuclear Information System (INIS)

    Box, W.D.; Shappert, L.B.; Seagren, R.D.; Klima, B.B.; Jurgensen, M.C.; Hammond, C.R.; Watson, C.D.

    1980-01-01

    An analytical evaluation of the Oak Ridge National Laboratory TRU Californium Shipping Container was made in order to demonstrate its compliance with the regulations governing off-site shipment of packages that contain radioactive material. The evaluation encompassed five primary categories: structural integrity, thermal resistance, radiation shielding, nuclear criticality safety, and quality assurance. The results of this evaluation demonstrate that the container complies with the applicable regulations

  19. Neutron emission in fission of highly excited californium nuclei (E*=76 MeV)

    International Nuclear Information System (INIS)

    Blinov, M.V.; Bordyug, V.M.; Kozulin, Eh.M.; Mozhaev, A.N.; Levitovich, M.; Muzychka, Yu.A.; Penionzhkevich, Yu.Eh.; Pustyl'nik, B.I.

    1990-01-01

    The differential cross sections for neutron production in the fission of highly excited californium nuclei formed in the 238 U+ 12 C (105 MeV) reaction have been measured. From the analysis of the experimental data is follows that the number of pre-fission neutrons substantially exceeds the value obtained in the framework of the standard statistical model. The saddle-to-scission time of the excited nucleus is estimated on the basis of the neutron multiplicity. The dependences of the neutron number and neutron average energies upon the fragment mass are determined

  20. Neutron emission in fission of highly excited californium nuclei (E* = 76 MeV)

    International Nuclear Information System (INIS)

    Blinov, M.V.; Bordyug, V.M.; Kozulin, E.M.; Levitovich, M.; Mozhaev, A.N.; Muzychka, Yu.A.; Penionzhkevich, Yu.E.; Pustyl'nik, B.I.

    1990-01-01

    Differential cross sections for neutron production have been measured in fission of excited californium nuclei produced in the reaction 238 U + 12 C (105 MeV). It follows from analysis of the experimental results that the number of neutrons emitted before fission considerably exceeds the number obtained in the framework of the standard statistical model. On the basis of the multiplicity of neutrons they authors have estimated the time of fission of the excited nucleus. The dependence of the number of neutrons and their average energies on the mass of the fragments is determined

  1. 14 CFR 23.237 - Operation on water.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Operation on water. 23.237 Section 23.237... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Flight Ground and Water Handling Characteristics § 23.237 Operation on water. A wave height, demonstrated to be safe for operation, and any...

  2. A californium-252 source for radiobiological studies at Hiroshima University

    International Nuclear Information System (INIS)

    Kato, Kazuo; Takeoka, Seiji; Kuroda, Tokue; Tsujimura, Tomotaka; Kawami, Masaharu; Hoshi, Masaharu; Sawada, Shozo

    1987-01-01

    A 1.93 Ci (3.6 mg) californium-252 source was installed in the radiation facility of the Research Institute for Nuclear Medicine and Biology, Hiroshima University. This source produces fission neutrons (8.7 x 10 9 n/s at the time of its installation), which are similar to neutron spectrum of the atomic bombs. It is useful for studying biological effects of fission neutrons and neutron dosimetry. An apparatus was dosigned to accomodate this source and to apply it to such studies. It has resulted in profitable fission neutron exposures, while suppressing scattered neutrons and secondary gamma rays. This apparatus incorporates many safety systems, including one which interlocks with all of doors and an elevator serving the exposure room, so as to prevent accidents involving users. (author)

  3. Californium production at the transuranium processing plant

    International Nuclear Information System (INIS)

    King, L.J.

    1976-01-01

    The Transuranium Processing Plant (TRU) at ORNL, which is the production, storage, and distribution center for the ERDA heavy element research program, is described. About 0.5 percent of 252 Cf is currently being produced. TRU is a hot-cell, chemical processing facility of advanced design. New concepts have been incorporated into the facility for absolute containment, remote operation, remote equipment installation, and remote maintenance. The facilities include a battery of nine heavily shielded process cells served by master-slave manipulators and eight laboratories, four on each of two floors. Processing includes chemical dissolution of the targets followed by a series of solvent extraction, ion exchange, and precipitation steps to separate and purify the transuranium elements. The transcurium elements Bk, Cf, Es, and Fm are distributed to users. Remote techniques are used to fabricate the Am and Cm into target rods for reirradiation in the HFIR. Californium-252 that is in excess of the needs of the heavy element research program and the Cf sales program is stored at TRU and processed repeatedly to recover the daughter product 248 Cm, which is a highly desirable research material

  4. Comparison of the Savannah River Site billet active well coincidence counter and two Californium Shufflers

    International Nuclear Information System (INIS)

    Sadowski, E.T.; Griffin, J.C.; Rinard, P.M.

    1991-01-01

    A Scrap Californium Shuffler at the Savannah River Site (SRS) was calibrated to assay the U-Al cores of billets (an intermediate step in the SRS reactor fuel fabrication cycle.) The precision of the Scrap Shuffler over several years has been approximately 0.50%. A typical total uncertainty for the assay of a core on the Scrap Shuffler is approximately 0.33% for a twelve minute assay. The precision over several months and a typical total uncertainty for the Billet Active Well (neutron) Coincidence Counter (BAWCC) are approximately 1.0% and 1.9%, respectively, for a fifteen minute assay. A new Billet Californium Shuffler specifically designed for assaying SRS billets has yielded precision (over one month) and total uncertainty results of 0.40% and 0.69%, respectively, for an eight minute assay. The introduction of a measurement point into the fuel fabrication cycle to replace estimates based upon material weight will greatly enhance material and process control in the Reactor Materials area of SRS. The use of all three instruments provides a comparison of the relative merits of Active Well (neutron) Coincidence Counters (AWCCs) and shufflers for assay of homogeneous and geometrically simple material containing 235 U. The measurement precisions, systematic and random uncertainties, as well as the procurement and operation of each instrument will be compared. 3 refs., 5 figs., 1 tab

  5. Measurement of californium-252 gamma photons depth dose distribution in tissue equivalent material. Vol. 4

    Energy Technology Data Exchange (ETDEWEB)

    Fadel, M A; El-Fiki, M A; Eissa, H M; Abdel-Hafez, A; Naguib, S H [National Institute of Standards, Cairo (Egypt)

    1996-03-01

    Phantom of tissue equivalent material with and without bone was used measuring depth dose distribution of gamma-rays from californium-252 source. The source was positioned at center of perspex walled phantom. Depth dose measurements were recorded for X, Y and Z planes at different distances from source. TLD 700 was used for measuring the dose distribution. Results indicate that implantation of bone in tissue equivalent medium cause changes in the gamma depth dose distribution which varies according to variation in bone geometry. 9 figs.

  6. Np-237 in peat and lichen in Finland

    DEFF Research Database (Denmark)

    Salminen, S.; Paatero, J.; Roos, Per

    2009-01-01

    Activity concentrations of 237Np in peat and lichen samples in Finland were determined and contributions from nuclear weapons testing in 1950–1960s and the Chernobyl accident were estimated. 237Np was determined with ICP-MS using 235Np as a tracer. Activity concentrations of 237Np in peat samples...

  7. Criticality of a 237Np sphere

    International Nuclear Information System (INIS)

    Sanchez, Rene; Loaiza, David; Kimpland, Robert; Hayes, David; Cappiello, Charlene; Chadwick, Mark

    2006-01-01

    For the past five years, scientists at Los Alamos National Laboratory have mounted an unprecedented effort to get a better estimate of the critical mass of 237 Np. To accomplish this task, a 6-kg neptunium sphere was recently cast at the Chemical and Metallurgy Research (CMR) facility, which is part of the Los Alamos National Laboratory. The neptunium sphere was clad with tungsten and nickel to reduce the dose rates from the 310 keV gamma rays from the first daughter of neptunium, namely, 233 Pa. 237 Np is a byproduct of power production in nuclear reactors. It is primarily produced by successive neutron captures in 235 U or through the (n,2n) reaction in 238 U. These nuclear reactions lead to the production of 237 U, which decays by beta emission into 237 Np, namely, 235 U(n,γ) 236 U, 236 U(n,γ) 237 U→β→ 237 Np, 238 U (n,2n) 237 U→β→ 237 Np. It is estimated that a typical 1000 MW(e) produces on the order of 12 to 13 kg of neptunium in a year. Some of this neptunium in irradiated fuel elements has been separated and is presently stored in containers in a liquid form. This method of storage is quite adequate because the fission cross section for 237 Np at thermal energies is quite low and any moderation of the neutron population by diluting the configurations with water would increase the critical mass to infinity. However, for long term storage, the neptunium liquid solutions must be converted into oxides and metals because these form are less movable and less likely to leak out of containers. Metals and oxides made out of neptunium have finite critical masses but there is a great uncertainty about these values because of the lack of experimental criticality data. Knowing precisely the critical mass of neptunium not only will help to validate mass storage limits or optimize storage configurations for safe disposition of these materials, but will also save thousands of dollars in transportation and disposition costs. The experimental results presented in

  8. Hypoxic versus normoxic external-beam irradiation of cervical carcinoma combined with californium-252 neutron brachytherapy. Comparative treatment results of a 5-year randomized study

    Czech Academy of Sciences Publication Activity Database

    Tačev, T.; Vacek, Antonín; Ptáčková, B.; Strnad, V.

    2005-01-01

    Roč. 181, č. 5 (2005), s. 273-284 ISSN 0179-7158 Institutional research plan: CEZ:AV0Z50040507 Keywords : cervical carcinoma * hypoxyradiotherapy * californium-252 Subject RIV: BO - Biophysics Impact factor: 3.490, year: 2005

  9. Ab initio full-potential study of mechanical properties and magnetic phase stability of californium monopnictides (CfN and CfP)

    Energy Technology Data Exchange (ETDEWEB)

    Amari, S., E-mail: siham_amari@yahoo.fr [Faculté des Sciences de la Nature et de la Vie, Université Hassiba Benbouali, Chlef, 02000 (Algeria); Bouhafs, B. [Laboratoire de Modélisation et Simulation en Sciences des Matériaux, Université Djillali Liabès de Sidi Bel-Abbés, Sidi Bel-Abbés, 22000 (Algeria)

    2016-09-15

    Based on the first-principles methods, the structural, elastic, electronic, properties and magnetic ordering of californium monopnictides CfX (X = P) have been studied using the full-potential augmented plane wave plus local orbitals (FP-L/APW + lo) method within the framework of density functional theory (DFT). The electronic exchange correlation energy is described by generalized gradient approximation GGA and GGA+U (U is the Hubbard correction). The GGA+U method is applied to the rare-earth 5f states. We have calculated the lattice parameters, bulk modulii and the first pressure derivatives of the bulk modulii. The elastic properties of the studied compounds are only investigated in the most stable calculated phase. In order to gain further information, we have calculated Young’s modulus, shear modulus, anisotropy factor and Kleinman parameter by the aid of the calculated elastic constants. The results mainly show that californium monopnictides CfX (X = P) have an antiferromagnetic spin ordering. Density of states (DOS) and charge densities for both compounds are also computed in the NaCl (B1) structure.

  10. Study of the shielding for spontaneous fission sources of Californium-252; Estudio de blindaje para fuentes de fision espontanea de Californio-252

    Energy Technology Data Exchange (ETDEWEB)

    Davila R, I

    1991-06-15

    A shielding study is made to attenuate, until maximum permissible levels, the neutrons radiation and photons emitted by spontaneous fission coming from a source of Californium-252. The compound package by a database (Library DLC-23) and the ANISNW code is used, in it version for personal computer. (Author)

  11. Possible stabilization of the tetravalent oxidation state of berkelium and californium in acetonitrile with triphenylarsine oxide

    International Nuclear Information System (INIS)

    Payne, G.F.; Peterson, J.R.

    1987-01-01

    It appears that we may have prepared Bk(IV) nitrate.nTPAs0 and Bk(IV) perchlorate.nTPAs0 complexes which formed the corresponding Cf(IV) complexes through the beta decay of Bk-249. Definitive proof should come from similar experiments with quantities of Bk-249 large enough to allow spectrophotometric detection of the characteristic f→f transitions in these berkelium and californium species. It is clear, however, that TPAs0 and acetonitrile can play a pivotal role in the stabilization of lanact(IV) species

  12. 48 CFR 1252.237-70 - Qualifications of contractor employees.

    Science.gov (United States)

    2010-10-01

    ... contractor employees. 1252.237-70 Section 1252.237-70 Federal Acquisition Regulations System DEPARTMENT OF....237-70 Qualifications of contractor employees. As prescribed in (TAR) 48 CFR 1237.110(a), insert the following clause: Qualifications of Contractor Employees (APR 2005) a. Definitions. As used in this clause...

  13. Experimental studies on californium bioavailability to marine benthic invertebrates

    International Nuclear Information System (INIS)

    Fowler, S.W.; Carvalho, F.P.; Aston, S.R.

    1986-01-01

    252 Cf is readily taken up by benthic invertebrates from sea water, reaching whole-body concentration factors of 763 in the polychaete Hermione hystrix, 220 in the shrimp Lysmata seticaudata, 665 in the crab Pilumnus hirtellus and 78 in the bivalve mollusc Venerupis decussata after 3 weeks exposure. Surface sorption plays a predominant role in the uptake process. Depuration in clean sea water was a relatively slow process. The shrimp Lysmata eliminated 252 Cf very rapidly due to moulting. Absorption coefficients for ingested 252 Cf were high, approx. 23% in crabs and approx. 97% in brittlestars. The absorbed fraction was excreted twice as fast from crabs as brittlestars. Exposure of organisms to labelled sediment resulted in low transfer factors that were species dependent. There is some evidence to suggest that uptake from sediments is primarily due to 252 Cf transfer from the pore water. Comparison of these results with published experimental data on other transuranic nuclides in the same or similar species suggests that californium bioavailability is roughly equivalent to that of plutonium and americium. (author)

  14. 48 CFR 252.237-7011 - Preparation history.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Preparation history. 252... Provisions And Clauses 252.237-7011 Preparation history. As prescribed in 237.7003(b), use the following clause: Preparation History (DEC 1991) For each body prepared, or for each casket handled in a group...

  15. Characterization of oxalate-based 237NpO2 powder

    International Nuclear Information System (INIS)

    Rankin, D.T.; Burney, G.A.; Smith, P.K.; Sisson, R.D.

    1976-01-01

    238 Pu, a radioisotope heat source, is produced by irradiating reactor targets containing 237 NpO 2 . The neptunium oxide is obtained by precipitating and calcining 237 Np(IV) oxalate. The effects of oxalate precipitation parameters on particle morphology and size distribution of 237 NpO 2 powder were established to provide process controls for fabricating reactor targets

  16. Biokinetics of 237Np in mussels and shrimp

    International Nuclear Information System (INIS)

    Guary, J.C.; Fowler, S.W.

    1977-01-01

    Neptunium-237 kinetics were studied in marine shrimp and mussels using a thick source alpha counting technique. Bioaccumulation of 237 Np from water was relatively slow in both species, reaching whole body concentration factors of only 15 to 20 after three months. Surface adsorption was implicated in the initial uptake. Both uptake and loss of the radioisotope were not significantly affected by temperature; this may be a reflection of the physical nature of the uptake. By virtue of the large amounts of accumulated 237 Np associated with the exoskeleton of shrimp, molting will play an important role in the biogeochemical cycling of this transuranic in the marine environment. Rapid growth of organisms like mussels acts to reduce the 237 Np concentration in tissues during a period of decontamination

  17. 48 CFR 252.237-7005 - Performance and delivery.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Performance and delivery... of Provisions And Clauses 252.237-7005 Performance and delivery. As prescribed in 237.7003(b), use the following clause: Performance and Delivery (DEC 1991) (a) The Contractor shall furnish the...

  18. 48 CFR 252.237-7007 - Termination for default.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Termination for default... of Provisions And Clauses 252.237-7007 Termination for default. As prescribed in 237.7003(b), use the following clause: Termination for Default (DEC 1991) (a) This clause supplements and is in addition to the...

  19. 48 CFR 237.7502 - Policy.

    Science.gov (United States)

    2010-10-01

    ... DEFENSE SPECIAL CATEGORIES OF CONTRACTING SERVICE CONTRACTING Acquisition and Management of Industrial Resources 237.7502 Policy. (a) Comply with DoD Directive 4275.5, Acquisition and Management of Industrial...

  20. Californium-252 Brachytherapy Combined With External-Beam Radiotherapy for Cervical Cancer: Long-Term Treatment Results

    International Nuclear Information System (INIS)

    Lei Xin; Qian Chengyuan; Qing Yi; Zhao Kewei; Yang Zhengzhou; Dai Nan; Zhong Zhaoyang; Tang Cheng; Li Zheng; Gu Xianqing; Zhou Qian; Feng Yan; Xiong Yanli; Shan Jinlu; Wang Dong

    2011-01-01

    Purpose: To observe, by retrospective analysis, the curative effects and complications due to californium-252 ( 252 Cf) neutron intracavitary brachytherapy (ICBT) combined with external-beam radiotherapy (EBRT) in the treatment of cervical cancer. Methods and Materials: From February 1999 to December 2007, 696 patients with cervical cancer (Stages IB to IIIB) were treated with 252 Cf-ICBT in combination of EBRT. Of all, 31 patients were at Stage IB, 104 at IIA, 363 at IIB, 64 at IIIA, and 134 at IIIB. Californium-252 ICBT was delivered at 7–12 Gy per insertion per week, with a total dose of 29–45 Gy to reference point A in three to five insertions. The whole pelvic cavity was treated with 8-MV X-ray external irradiation at 2 Gy per fraction, four times per week. After 16–38 Gy of external irradiation, the center of the whole pelvic field was blocked with a 4-cm-wide lead shield, with a total external irradiation dose of 44–56 Gy. The total treatment course was 5 to 6 weeks. Results: Overall survival rate at 3 and 5 years for all patients was 76.0% and 64.9%, respectively. Disease-free 3- and 5-year survival rates of patients were 71.2% and 58.4%, respectively. Late complications included vaginal contracture and adhesion, radiation proctitis, radiation cystitis, and inflammatory bowel, which accounted for 5.8%, 7.1%, 6.2%, and 4.9%, respectively. Univariate analysis results showed significant correlation of stage, age, histopathologic grade, and lymph node status with overall survival. Cox multiple regression analysis showed that the independent variables were stage, histopathologic grade, tumor size, and lymphatic metastasis in all patients. Conclusion: Results of this series suggest that the combined use of 252 Cf-ICBT with EBRT is an effective method for treatment of cervical cancer.

  1. 48 CFR 1352.237-72 - Security processing requirements-national security contracts.

    Science.gov (United States)

    2010-10-01

    ... requirements-national security contracts. 1352.237-72 Section 1352.237-72 Federal Acquisition Regulations... Provisions and Clauses 1352.237-72 Security processing requirements—national security contracts. As prescribed in 48 CFR 1337.110-70(d), use the following clause: Security Processing Requirements—National...

  2. 43 CFR 23.7 - Approval of exploration plan.

    Science.gov (United States)

    2010-10-01

    ... measures to be taken to prevent or control fire, soil erosion, pollution of surface and ground water... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Approval of exploration plan. 23.7 Section 23.7 Public Lands: Interior Office of the Secretary of the Interior SURFACE EXPLORATION, MINING AND...

  3. Teratogenic effect of Californium-252 irradiation in rats

    International Nuclear Information System (INIS)

    Satow, Yukio; Lee, Juing-Yi; Hori, Hiroshi; Okuda, Hiroe; Tsuchimoto, Shigeo; Sawada, Shozo; Yokoro, Kenjiro

    1989-01-01

    The teratogenicity of Californium-252 (Cf-252) irradiation which generates approximately 70% 2.3 MeV fast neutron and 30% gamma rays was evaluated. A single whole body exposure of Cf-252 at various doses was given to pregnant rats on day 8 or 9 of pregnancy, followed by microscopic autopsy of the fetuses at the terminal stage of pregnancy to search for external and internal malformations. For comparison, pregnant rats were irradiated with various doses of Cobalt-60 (Co-60) standard gamma rays at the same dose rate (1 rad/min.). The doses were 20-120 rad of Cf-252 and 80-220 rad of Co-60. Using frequency of radiation induced malformations observed on day 8 of pregnancy as an index, relative biological effectiveness (RBE) of 2.3-2.7 was obtained from the straight line obtained by modifying by the least squares method the frequency curves of malformed fetuses in total implants and in surviving fetuses. The types of malformations induced by Cf-252 and Co-60 irradiation were alike. Using fetal LD 50 as an index, 2.4 was obtained as RBE when irradiated on day 8 of pregnancy and 3.1 as that when irradiated on day 9. The results showed that Cf-252 had stronger a teratogenic effect than Co-60 gamma rays. (author)

  4. 48 CFR 237.7100 - Scope.

    Science.gov (United States)

    2010-10-01

    ... DEFENSE SPECIAL CATEGORIES OF CONTRACTING SERVICE CONTRACTING Laundry and Dry Cleaning Services 237.7100 Scope. This subpart— (a) Applies to contracts for laundry and dry cleaning services within the United...

  5. Sorption and Migration Mechanisms of 237 Np through Sandy Soil

    International Nuclear Information System (INIS)

    Chantaraprachoom, Nanthavan; Tanaka, Tadao

    2003-06-01

    In order to evaluate migration behavior of radioactive nuclides in the disposal of low-level radioactive waste into a shallow land burial, the sorption characteristic and migration behavior of 237 Np through sandy soil was studied. Two experimental methods were performed by using batch and column systems. The distribution coefficients (K d ) obtained from the adsorption and desorption process are rather small about 16 and 21 cm 3 /g respectively. Size distribution of 237 Np species in the influent solution was measured by ultra-filtration technique. Migration mechanism of 237 Np was studied by column experiments. The experimental condition was the influence of volume of eluting solution; 100, 300, 500, 1000 and 2000 ml respectively. The result from five column experiments confirm that the sorption characteristics of 237 Np are mainly controlled by a reversible ion-exchange reaction and the migration of 237 Np in the sandy soil can be estimated by using the K d concept

  6. 48 CFR 2452.237-73 - Conduct of Work and Technical Guidance.

    Science.gov (United States)

    2010-10-01

    ... conditions of the contract. (c) The GTR will issue technical guidance in writing or, if issued orally, he/she... Technical Guidance. 2452.237-73 Section 2452.237-73 Federal Acquisition Regulations System DEPARTMENT OF... Provisions and Clauses 2452.237-73 Conduct of Work and Technical Guidance. As prescribed in 2437.110(d...

  7. Transport calculations of. gamma. -ray flux density and dose rate about implantable californium-252 sources

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, A; Lin, B I [Cincinnati Univ., Ohio (USA). Dept. of Chemical and Nuclear Engineering; Windham, J P; Kereiakes, J G

    1976-07-01

    ..gamma.. flux density and dose rate distributions have been calculated about implantable californium-252 sources for an infinite tissue medium. Point source flux densities as a function of energy and position were obtained from a discrete-ordinates calculation, and the flux densities were multiplied by their corresponding kerma factors and added to obtain point source dose rates. The point dose rates were integrated over the line source to obtain line dose rates. Container attenuation was accounted for by evaluating the point dose rate as a function of platinum thickness. Both primary and secondary flux densities and dose rates are presented. The agreement with an independent Monte Carlo calculation was excellent. The data presented should be useful for the design of new source configurations.

  8. Neutron Data Evaluation of 237Np

    International Nuclear Information System (INIS)

    Maslov, V.M.; Tetereva, N.A.; Kolesov, A.M.; Pronyaev, V.G.; Zolotarev, K.I.; Granier, T.; Hambsch, F.-J.

    2010-11-01

    The diverse measured data base of n+ 237 Np was evaluated using a statistical theory and generalized least squares codes. Consistent description of the total, fission and partial inelastic scattering data in 1-3 MeV energy range provides an important constraint for the absorption cross section, which is quite important for the robust estimate of the capture cross section in the 0.5-500 keV energy range. Important constraints for the measured capture cross section come from the average radiative S0 and S1 strength functions. The evaluated inelastic cross sections of available evaluations are in severe disagreement with measured data on the inelastic scattering of neutrons with excitation of specific groups of levels. A change of the inelastic data shape at E n ∼1.5 MeV might be explained by the sharp increase of the level density of the residual odd-even nuclide 237 Np due to the onset of three-quasi-particle excitations. The influence of exclusive (n, xnf) pre-fission neutrons on prompt fission neutron spectra (PFNS) and (n, xn) spectra is modeled. Contributions of emissive/non-emissive fission and exclusive spectra of (n, xnf) reactions are defined by a consistent description of the 237 Np (n, F), 237 Np (n, 2n) 236s Np reactions and the ratio of the yields of short-lived (1 - ) and long-lived (6 - ) 236 Np states measured at 14 MeV. Excited levels of 236 Np are modeled using predicted Gallher-Moshkowski doublets. This work is performed under the project Agreement B-1604 with the International Science and Technology Center (Moscow). The financing party is EU. Partial support of International Atomic Energy Agency under Research Contract 14809 is acknowledged by JINER. (author)

  9. 48 CFR 1452.237-71 - Utilization of Woody Biomass.

    Science.gov (United States)

    2010-10-01

    ... Biomass. 1452.237-71 Section 1452.237-71 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR... Utilization of Woody Biomass. As prescribed in § 1437.7202, insert the following clause: Utilization of Woody Biomass (MAY 2005) (a) The contractor may remove and utilize woody biomass, if: (1) Project work is...

  10. Chemical aspects of 237 Np Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Karraker, D.G.

    1984-01-01

    The 237 Np Moessbauer effect has been especially useful in studies of neptunium chemistry, by virtue of its excellent resolution and straightforward experimental techniques. Neptunium can have valences from +3 to +7, and a broad range of compounds can be prepared that are analogous to those of other actinide elements. Studies on neptunium compounds, for example, have a ready application to the analogous compounds of uranium and plutonium. The emphasis in this paper will be on the application of the 237 Np Moessbauer effect to problems in neptunium chemistry

  11. 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

  12. 48 CFR 352.237-71 - Crime Control Act-reporting of child abuse.

    Science.gov (United States)

    2010-10-01

    ...-reporting of child abuse. 352.237-71 Section 352.237-71 Federal Acquisition Regulations System HEALTH AND... Clauses 352.237-71 Crime Control Act—reporting of child abuse. As prescribed in 337.103-70(b), the Contracting Officer shall insert the following clause: Crime Control Act of 1990—Reporting of Child Abuse...

  13. Neutron activation analysis at the Californium User Facility for Neutron Science

    International Nuclear Information System (INIS)

    Martin, R.C.; Smith, E.H.; Glasgow, D.C.; Jerde, E.A.; Marsh, D.L.; Zhao, L.

    1997-12-01

    The Californium User Facility (CUF) for Neutron Science has been established to provide 252 Cf-based neutron irradiation services and research capabilities including neutron activation analysis (NAA). A major advantage of the CUF is its accessibility and controlled experimental conditions compared with those of a reactor environment The CUF maintains the world's largest inventory of compact 252 Cf neutron sources. Neutron source intensities of ≤ 10 11 neutrons/s are available for irradiations within a contamination-free hot cell, capable of providing thermal and fast neutron fluxes exceeding 10 8 cm -2 s -1 at the sample. Total flux of ≥10 9 cm -2 s -1 is feasible for large-volume irradiation rabbits within the 252 Cf storage pool. Neutron and gamma transport calculations have been performed using the Monte Carlo transport code MCNP to estimate irradiation fluxes available for sample activation within the hot cell and storage pool and to design and optimize a prompt gamma NAA (PGNAA) configuration for large sample volumes. Confirmatory NAA irradiations have been performed within the pool. Gamma spectroscopy capabilities including PGNAA are being established within the CUF for sample analysis

  14. 49 CFR 237.9 - Waivers.

    Science.gov (United States)

    2010-10-01

    ... TRANSPORTATION BRIDGE SAFETY STANDARDS General § 237.9 Waivers. (a) Any person subject to a requirement of this... compliance is in the public interest and is consistent with railroad safety, the Administrator may grant the... Administrator publishes a notice in the Federal Register containing the reasons for granting the waiver. ...

  15. Neutron induced fission of 237Np – status, challenges and opportunities

    Directory of Open Access Journals (Sweden)

    Ruskov Ivan

    2018-01-01

    Full Text Available Nowadays, there is an increased interest in a complete study of the neutron-induced fission of 237Np. This is due to the need of accurate and reliable nuclear data for nuclear science and technology. 237Np is generated (and accumulated in the nuclear reactor core during reactor operation. As one of the most abundant long-lived isotopes in spent fuel (“waste”, the incineration of 237Np becomes an important issue. One scenario for burning of 237Np and other radio-toxic minor actinides suggests they are to be mixed into the fuel of future fast-neutron reactors, employing the so-called transmutation and partitioning technology. For testing present fission models, which are at the basis of new generation nuclear reactor developments, highly accurate and detailed neutron-induced nuclear reaction data is needed. However, the EXFOR nuclear database for 237Np on neutron-induced capture cross-section, σγ, and fission cross-section, σf, as well as on the characteristics of capture and fission resonance parameters (Γγ, Γf, σoΓf, fragments mass-energy yield distributions, multiplicities of neutrons vn and γ-rays vγ, has not been updated for decades.

  16. Application of californium-252 neutron sources for analytical chemistry

    International Nuclear Information System (INIS)

    Ishii, Daido

    1976-01-01

    The researches made for the application of Cf-252 neutron sources to analytical chemistry during the period from 1970 to 1974 including partly 1975 are reviewed. The first part is the introduction to the above. The second part deals with general review of symposia, publications and the like. Attention is directed to ERDA publishing the periodical ''Californium-252 Progress'' and to a study group of Cf-252 utilization held by Japanese Radioisotope Association in 1974. The third part deals with its application for radio activation analysis. The automated absolute activation analysis (AAAA) of Savannha River is briefly explained. The joint experiment of Savannha River operation office with New Brunswick laboratory is mentioned. Cf-252 radiation source was used for the non-destructive analysis of elements in river water. East neutrons of Cf-252 were used for the quantitative analysis of lead in paints. Many applications for industrial control processes have been reported. Attention is drawn to the application of Cf-252 neutron sources for the field search of neutral resources. For example, a logging sonde for searching uranium resources was developed. the fourth part deals with the application of the analysis with gamma ray by capturing neutrons. For example, a bore hole sonde and the process control analysis of sulfur in fuel utilized capture gamma ray. The prompt gamma ray by capturing neutrons may be used for the nondestructive analysis of enrivonment. (Iwakiri, K.)

  17. Spectral investigation of neutron radiation in three-sectional concrete labyrinth from a californium-252 source

    International Nuclear Information System (INIS)

    Belogorlov, E.A.; Britvich, G.I.; Getmanov, V.B.

    1985-01-01

    Construction of labyrinths in points of communication output from the storage-ring under construction is accompanied by numerous difficulties due to a considerable number of gas and cryogenic pipelines, which require large cross sections at the minimal length of the pipelines proper for their location. It results in unfavourable for radiation attenuation ratios between cross section and length of the labyrinth separate sections. Neutron spectra in a model concrete labyrinth, at the entrance to which a neutron source with fission spectrum (californium-252) and the same source in a polyethylene moderator are located, are measured. On the basis of the spectra obtained the formation of fluence and equivalent dose along the labyrinth geometric axis is analyzed. Conditions permitting actually to reduce radiation dose in the labyrinth (dead end provision, the use of cover materials, construction of diaphragms and shielding plates) are simulated

  18. 7 CFR 205.237 - Livestock feed.

    Science.gov (United States)

    2010-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.237 Livestock feed. (a... specific stage of life; (3) Feed plastic pellets for roughage; (4) Feed formulas containing urea or manure...

  19. 32 CFR 237a.4 - Procedures.

    Science.gov (United States)

    2010-07-01

    ...); (c) Industrial programs which are in support of Government policy (example—international exhibits..., authorized by part 237 of this subchapter to apprise defense contractors, trade associations and other... governing research, development and production, and the procurement of goods and services, and serve as a...

  20. Use of polyethylene pellets in the design and construction of a storage safe, a transport vessel and a portable shield for californium-252

    International Nuclear Information System (INIS)

    Sharma, S.

    1986-01-01

    A storage and shielding facility for 300 μg of Californium-252 sources was designed and constructed. Though the safe was in a permanent location, the fact that it consisted of a lead bucket surrounded by polyethylene pellets made it simple, movable and inexpensive. If need be, more quantities of Cf-252 could be added without altering the basic design and sacrificing the radiation protection guidelines. The measured radiation levels from 300 μg of stored Cf-252 in and around the storage vault were lower than the expected dose rates by a factor of 5. The measured radiation levels around the occupied environs of the facility were below the maximum permissible yearly dose of 500mrem for non-occupational workers. A transport vessel was designed and constructed to carry up to 50 μg of Californium-252 sources. It consisted of a standard 55 gallon steel drum on casters containing cylindrical lead shield surrounded by polyethylene pellets. The measured maximum surface dose rates on the drum and at one meter away were within the radiation protection guidelines and were less than the expected dose rates. A portable shield was designed and constructed to protect the body in afterloading operations and handling of the sources. It consisted of polyethylene pellets in an aluminum box and an attached 10 cm thick plexiglass eye shield. The simple design, with the ease of using polyethylene pellets can be extended to construct bedside shields

  1. Conversion-electron experiment to characterize the decay of the 237Np shape isomer

    International Nuclear Information System (INIS)

    Henry, E.A.; Becker, J.A.; Bauer, R.W.; Gardner, D.G.; Decman, D.J.; Meyer, R.A.; Roy, N.; Sale, K.E.

    1987-01-01

    Conversion electrons from the decay of low-lying levels of 237 Np have been measured to detect the population of these levels by gamma-ray decay of the 237 Np shape isomer. Analysis of the 208-keV transition L conversion-electron peak gives an upper limit of about 17 μb for the population of the 3/2 - 267-keV level in 237 Np from the shape isomer decay. Model calculations are compared with the measured limit. Improvements are suggested for this experiment. 9 refs., 4 figs

  2. 48 CFR 852.237-70 - Contractor responsibilities.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contractor....237-70 Contractor responsibilities. As prescribed in 837.110, insert the following clause: Contractor Responsibilities (APR 1984) The contractor shall obtain all necessary licenses and/or permits required to perform...

  3. 49 CFR 237.155 - Documents and records.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Documentation, Records, and Audits of Bridge Management Programs § 237.155 Documents and records. Each track owner required to implement a bridge management... protected by a security system that incorporates a user identity and password, or a comparable method, to...

  4. Extraction of Trivalent Actinides and Lanthanides from Californium Campaign Rework Solution Using TODGA-based Solvent Extraction System

    Energy Technology Data Exchange (ETDEWEB)

    Benker, Dennis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Delmau, Laetitia Helene [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dryman, Joshua Cory [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-07-01

    This report presents the studies carried out to demonstrate the possibility of quantitatively extracting trivalent actinides and lanthanides from highly acidic solutions using a neutral ligand-based solvent extraction system. These studies stemmed from the perceived advantage of such systems over cationexchange- based solvent extraction systems that require an extensive feed adjustment to make a low-acid feed. The targeted feed solutions are highly acidic aqueous phases obtained after the dissolution of curium targets during a californium (Cf) campaign. Results obtained with actual Cf campaign solutions, but highly diluted to be manageable in a glove box, are presented, followed by results of tests run in the hot cells with Cf campaign rework solutions. It was demonstrated that a solvent extraction system based on the tetraoctyl diglycolamide molecule is capable of quantitatively extracting trivalent actinides from highly acidic solutions. This system was validated using actual feeds from a Cf campaign.

  5. 48 CFR 1852.237-71 - Pension portability.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Pension portability. 1852... 1852.237-71 Pension portability. As prescribed at 1837.110-70(b), insert the following clause: Pension Portability (JAN 1997) (a) In order for pension costs attributable to employees assigned to this contract to...

  6. Neutron activation analysis of the calcium content in vivo, using a 50μg source of californium 252

    International Nuclear Information System (INIS)

    Guey, A.; Zech, P.Y.; Meary, M.F.; Leitienne, P.

    1975-01-01

    Owing to the recent commercialisation of californium 252 it is now possible to obtain neutron fluxes strong enough for precise activation of the calcium content of biological targets. After the preliminary measurements necessary to establish the most suitable conditions for irradiating 3 to 5cm thick targets, two parallel sets of experiments were developed. In the first the medium-term total calcium variation was studied in 20 rats, 16 suffering from chronic kidney deficiency. In the second the precision expected as a function of the calcium content of the irradiated target was examined, using 3 sets of tissue equivalent standards of calcium contents 5, 20 and 50g respectively. The first results obtained on calcium 49 in vivo show that a calcium content variation can be followed with a sensitivity threshold below that obtained by conventional methods [fr

  7. 237 Np analytical method using 239 Np tracers and application to a contaminated nuclear disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Snow, Mathew S.; Morrison, Samuel S.; Clark, Sue B.; Olson, John E.; Watrous, Matthew G.

    2017-06-01

    Environmental 237Np analyses are challenged by low 237Np concentrations and lack of an available yield tracer; we report a rapid, inexpensive 237Np analytical approach employing the short lived 239Np (t1/2 = 2.3 days) as a chemical yield tracer followed by 237Np quantification using inductively coupled plasma-mass spectrometry. 239Np tracer is obtained via separation from a 243Am stock solution and standardized using gamma spectrometry immediately prior to sample processing. Rapid digestions using a commercial, 900 watt “Walmart” microwave and Parr microwave vessels result in 99.8 ± 0.1% digestion yields, while chromatographic separations enable Np/U separation factors on the order of 106 and total Np yields of 95 ± 4% (2σ). Application of this method to legacy soil samples surrounding a radioactive disposal facility (the Subsurface Disposal Area at Idaho National Laboratory) reveal the presence of low level 237Np contamination within 600 meters of this site, with maximum 237Np concentrations on the order of 103 times greater than nuclear weapons testing fallout levels.

  8. Role of ser-237 in the substrate specificity of the carbapenem-hydrolyzing class A beta-lactamase Sme-1.

    Science.gov (United States)

    Sougakoff, W; Naas, T; Nordmann, P; Collatz, E; Jarlier, V

    1999-08-17

    The role of the serine residue found at position 237 in the carbapenemase Sme-1 has been investigated by constructing a mutant in which Ser-237 was replaced by an alanine. The S237A mutant showed a catalytic behavior against penicillins and aztreonam very similar to that of Sme-1. By contrast, S237A was characterized by a reduced catalytic efficiency against cephems, such as cephalothin and cephaloridine. In addition, the weak activity of Sme-1 against the cephamycin cefoxitin was hardly detectable with the mutant enzyme. Finally, the Ser-237-->Ala mutation resulted in a marked decrease in catalytic activity against imipenem, showing that Ser-237 contributes to the carbapenemase activity of the class A beta-lactamase Sme-1.

  9. 237Np analytical method using 239Np tracers and application to a contaminated nuclear disposal facility.

    Science.gov (United States)

    Snow, Mathew S; Morrison, Samuel S; Clark, Sue B; Olson, John E; Watrous, Matthew G

    2017-06-01

    Environmental 237 Np analyses are challenged by low 237 Np concentrations and lack of an available yield tracer; we report a rapid, inexpensive 237 Np analytical approach employing the short lived 239 Np (t 1/2  = 2.3 days) as a chemical yield tracer followed by 237 Np quantification using inductively coupled plasma-mass spectrometry. 239 Np tracer is obtained via separation from a 243 Am stock solution and standardized using gamma spectrometry immediately prior to sample processing. Rapid digestions using a commercial, 900 W "Walmart" microwave and Parr microwave vessels result in 99.8 ± 0.1% digestion yields, while chromatographic separations enable Np/U separation factors on the order of 10 6 and total Np yields of 95 ± 4% (2σ). Application of this method to legacy soil samples surrounding a radioactive disposal facility (the Subsurface Disposal Area at Idaho National Laboratory) reveal the presence of low level 237 Np contamination within 600 m of this site, with maximum 237 Np concentrations on the order of 10 3 times greater than nuclear weapons testing fallout levels. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Use of californium-252 neutron irradiator for in-vivo analysis of the bone calcium content of the hand

    International Nuclear Information System (INIS)

    Guey, A.; Leitienne, P.; Zech, P.Y.; Traeger, J.; Doyen, J.B.; Breton, J.P.

    1979-01-01

    With californium-252 it is easy to obtain a high neutron flux of the order of 10 9 n/s. The mean energy of this radiation, which is close on 2 MeV, activates calcium very well. The authors describe a storage and irradiator unit with a 100 μg californium source, with which it will henceforth be possible to develop this technique of measuring the calcium of the hand in a hospital. The test programme has three distinct phases: (1) irradiation of the biological target for 10 min; (2) after a transfer period of 30 s, detection of the radiation emitted by the 49 Ca for 600 s; (3) processing of the numerical data received, which are transmitted on line to a T 1600 calculator. The weight is found by comparing the activity induced in the unknown calcium mass with that induced in a phantom chosen as the activity standard. The reproducibility of the method is of the order of 3% (5% at the worst). The gross standardized result is edited automatically. For physical and clinical reasons, the hand is chosen as the reference part of the body in 70 control subjects. The local irradiation dose is less than 2 rem. The bone calcium content is 14.3+-1.9 g in men and 10.1+-1.3 g in women. In clinical application of the technique it is necessary to differentiate between the normal calcium content and the calcium content found with a pathological state. This makes it necessary to express the measurement in the form of a volume mass (rho). The volume of the hand skeleton (V in cm 3 ) is calculated from the corresponding bone surface (S in cm 2 ) measured by planimetry with the relationship V=8.925 exp 0.0205.S, found after studying 80 hand skeletons. In our control subjects the calcium bone volume mass was 0.288 g/cm 3 in men and 0.282 g/cm 3 in women. There is a very significant difference (p<0.001) in a population of 88 subjects with chronic renal insufficiencies at the terminal stage: rho=0.233 in men and 0.235 in women

  11. Simulation and design of an electron beam ion source charge breeder for the californium rare isotope breeder upgrade

    Directory of Open Access Journals (Sweden)

    Clayton Dickerson

    2013-02-01

    Full Text Available An electron beam ion source (EBIS will be constructed and used to charge breed ions from the californium rare isotope breeder upgrade (CARIBU for postacceleration into the Argonne tandem linear accelerator system (ATLAS. Simulations of the EBIS charge breeder performance and the related ion transport systems are reported. Propagation of the electron beam through the EBIS was verified, and the anticipated incident power density within the electron collector was identified. The full normalized acceptance of the charge breeder with a 2 A electron beam, 0.024π  mm mrad for nominal operating parameters, was determined by simulating ion injection into the EBIS. The optics of the ion transport lines were carefully optimized to achieve well-matched ion injection, to minimize emittance growth of the injected and extracted ion beams, and to enable adequate testing of the charge bred ions prior to installation in ATLAS.

  12. 32 CFR 237a.3 - Objective and policy.

    Science.gov (United States)

    2010-07-01

    ...) MISCELLANEOUS PUBLIC AFFAIRS LIAISON WITH INDUSTRY § 237a.3 Objective and policy. (a) It is important that...D. Such understanding can be achieved by (1) wide dissemination of information to the business community, consistent with national security, and (2) cooperation with industry in public relations...

  13. 48 CFR 1552.237-76 - Government-Contractor Relations.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Government-Contractor... 1552.237-76 Government-Contractor Relations. As prescribed in 1537.110(g), insert the following clause: Government-Contractor Relations (JUN 1999) (a) The Government and the Contractor understand and agree that...

  14. Updated and revised neutron reaction data for 237Np

    Directory of Open Access Journals (Sweden)

    Chen Guochang

    2017-01-01

    Full Text Available Nuclear data with high accuracy for minor actinides play an important role in nuclear technology applications, including reactor design and operation, fuel cycle, estimation of the amount of minor actinides in high burn-up reactors and the minor actinides transmutation. Based on the evaluated experimental data, the updated and revised evaluation of a full set of n+237Np nuclear data from 10−5 eV ∼ 20 MeV are carried out and recommended. Mainly revised quantities are neutron multiplicities from fission reaction, inelastic, fission, (n, 2n and (n, γ reaction cross sections as well as angular distribution and so on. The promising results are obtained when the renewal evaluated data of 237Np will be used to instead of the evaluated data in CENDL-3.1 database.

  15. Analysis of Np-237 ENDF for the theortical interpretation of critical assembly experiments.

    Energy Technology Data Exchange (ETDEWEB)

    Mihaila, B. (Bogdan); Chadwick, M. B. (Mark B.); MacFarlane, R. E. (Robert E.); Kawano, T. (Toshihiko)

    2004-01-01

    We report on the present status of our effort toward an improved Np-237 evaluated nuclear data file (ENDF). The aim here is to bridge the gap between calculated and observed k-eff values, as measured at the Np-U critical assembly at LANL, TA-18. As such, we perform a critical analysis of the existing body of experimental data and recommended evaluations. We are targeting in principal the fission nu-bar and cross section in Np-237, as well as the inelastic scattering which is particularly important since Np-237 is a threshold fissioner. This analysis will be employed in a future sensitivity study of the calculated k-eff with respect to variations of the afore mentioned nuclear data.

  16. 48 CFR 2152.237-70 - Continuity of services.

    Science.gov (United States)

    2010-10-01

    ...-out services for up to 10 months after this contract expires and (2) negotiate in good faith a plan... contract. The Contractor also must, except if prohibited by applicable law, disclose necessary personnel... PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 2152.237-70 Continuity of services. As...

  17. 238U and 237Np nuclear fission by 90-270 MeV electrons

    International Nuclear Information System (INIS)

    Kuznetsov, V.L.; Nedorezov, V.G.; Nikitina, N.V.; Noga, V.I.; Ranyuk, Yu.N.; Telegin, Yu.N.; Smirnov, A.N.; Ehjsmont, V.P.

    1981-01-01

    A technique for measuring cross sections of 238 U and 237 Np nuclei fission caused by 90-270 MeV electrons is described. Measurement results are given. The results obtained are discussed on the basis of the virtual photon method. It is shown that the difference in cross sections of 238 U and 237 Np electrofission is due to the different contribution of the giant resonance [ru

  18. Integral test for Np237 and Am241 cross sections in JENDL, ENDF and JEF libraries

    International Nuclear Information System (INIS)

    Iwasaki, Tomohiko; Unesaki, Hironobu; Kitada, Takanori

    2002-01-01

    Experiments using Kyoto University critical assembly (KUCA) were performed for measuring the capture and fission reaction rates of 237 Np and 241 Am. A back-to-back fission chamber was employed for the measurement of the fission rate of 237 Np and 241 Am relative to 235 U. The capture rate of 237 Np relative to 197 Au was measured by using activation method. Eleven cores, of which the spectra were changed systematically, were mocked up for the present measurements. Five cores among the eleven were utilized for the fission reaction rate measurement. The experiment was analyzed using the Monte Carlo code MVP, the transport code TWOTRAN and the diffusion code CITATION using the libraries based on JENDL3.2, ENDF/B-VI and JEF2.2. As the results, for 237 Np, JENDL3.2 showed good agreement for both capture and fission. However, for the fission rate of 241 Am, JENDL3.2 underestimates 15-20%. On the other hand, ENDF/B-VI and JEF2.2 show different C/Es for 237 Np and 241 Am. (author)

  19. Long-term effects of an intracavitary treatment with californium-252 on normal tissue

    International Nuclear Information System (INIS)

    Sullivan, M.F.; Beamer, J.L.; Mahony, T.D.; Cross, F.T.; Lund, J.E.; Endres, G.W.R.

    1976-01-01

    About one hundred fifty swine were exposed to either radium-226 or californium-252 sources in the uterine cervix to determine an RBE for both acute and long-term effects. That value for early changes in the tissues at risk in the treatment of cervical cancer was between 6.2 and 6.8. The incidence of complications increased with time after exposure, especially among animals treated with 252 Cf. Analysis of rectal injury showed that ulceration occurred frequently within a year postexposure at doses between 1600 and 2400 rad calculated at 2 cm lateral to the source midline. Fat necrosis and smooth muscle atrophy, resulting in a local rectal stricture, were delayed changes observed in some animals. The lower ureter was the site for a greater frequency of complications than the GI tract. Ureteral stricture often occurred at doses of 1200 rad from 252 Cf and 7000 rad from 226 Ra. Observation of delayed effects in the uterine-cervix in animals held up to 4 years postexposure indicate that the RBE for 252 Cf may be increased to a value as high as 18, while repair may have even decreased it to about 5.6 in the rectum. Fifty swine are still being observed for long-term effects after doses above 800 rad from 252 Cf and 5000 rad from 226 Ra

  20. 15 CFR 23.7 - Notice to Department of Commerce organizational units of implementation and procedures.

    Science.gov (United States)

    2010-01-01

    ... organizational units of implementation and procedures. 23.7 Section 23.7 Commerce and Foreign Trade Office of the... Department of Commerce organizational units of implementation and procedures. Following are roles and...) Otherwise determine and control the use of missing children materials and information by the Operating Unit...

  1. 48 CFR 352.237-70 - Pro-Children Act.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Pro-Children Act. 352.237...-Children Act. As prescribed in 337.103-70(a), the Contracting Officer shall insert the following clause: Pro-Children Act (January 2006) (a) Public Law 103-227, Title X, Part C, also known as the Pro...

  2. Preparation of /sup 237/Np samples by electrodeposition and its determination by alpha spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mertzig, W; Matsuda, H T; Araujo, B.F. de; Araujo, J.A. de [Instituto de Pesquisas Energeticas e Nucleares, Sao Paulo (Brazil). Centro de Engenharia Quimica

    1980-01-01

    An analytical method followed by alpha spectrometry was developed for the determination of trace amounts of actinides. A technique for quantitative electrodeposition of /sup 237/Np, under optimal conditions, using a carrier, is presented. This method will be applied for the control of trace amounts of /sup 237/Np in the solutions from the reprocessing (Purex process) of irradiated uranium.

  3. Distribution of global fallout 237Np, Pu isotopes, and 241Am in lake and sea sediments

    International Nuclear Information System (INIS)

    Yamamoto, Masayoshi; Yamauchi, Y.; Chatani, K.; Komura, K.; Ueno, Kaoru; Sakanoue, Masanobu

    1991-01-01

    In order to investigate the sedimentary behaviour of neptunium, 237 Np together with Pu isotopes and 241 Am were measured for the sediment cores collected from Lake Mikata (freshwater), from Lake Kugushi (brakish water) and from Nyu Bay (sea water). In all sediment core samples 237 Np was detected, and its concentrations were far below those of 239,240 Pu and 241 Am measured for the same samples. Inventories of 237 Np in the lakes were estimated to be 0.53, 0.29 and 0.34 MBq/km 2 , respectively. The activity ratios of 237 Np/ 239,240 Pu, except for Lake Mikata, are two or three times lower than the value of 0.3-0.4% observed for surface soils of 0-20 cm depth, suggesting that Np is more soluble compared with Pu. (author) 21 refs.; 6 figs.; 3 tabs

  4. Neptunium-237 in the marine environment determination in animal and plant species in the English Channel

    International Nuclear Information System (INIS)

    Germian, P.

    1990-01-01

    The uptake of 237 Np was studied in marine plants and animals belonging to several phyla. Samples were collected from the end of January 1986 to March 1986 in a sampling station near the fuel reprocessing plant at La Hague. 237 Np was determined by neutron activation analysis. The transfer modes of 237 Np to the various species as a function of their trophic levels are discussed as well as the distribution among the organs in the species consumed and the radiological impact of human consumption. (author) 27 refs.; 2 figs.; 1 tab

  5. Role of once-daily glycopyrronium bromide (NVA237 in the management of COPD

    Directory of Open Access Journals (Sweden)

    D’Urzo A

    2013-08-01

    Full Text Available Anthony D'UrzoDepartment of Family and Community Medicine, University of Toronto, Toronto, ON, CanadaAbstract: Progressive airflow limitation is a hallmark feature of chronic obstructive pulmonary disease (COPD that ultimately leads to breathlessness, impaired quality of life, and reduced exercise capacity. Pharmacotherapy is used in patients with COPD to prevent and control symptoms, reduce both the frequency and severity of exacerbations, improve health status, and increase exercise tolerance. These strategies are intended to address management issues which promote both current disease control and a reduction in the risk of disease deterioration in the future. At the present time, long-acting β2-agonists (LABAs and long-acting muscarinic antagonists (LAMAs are available for maintenance therapy in patients with persistent symptoms. Tiotropium was the first LAMA to be approved for management of COPD, and many studies have described its beneficial effects on multiple clinically relevant outcomes. Glycopyrronium bromide (NVA237, a new LAMA, has been developed and received regulatory approval for management of COPD in a number of countries around the world. Results from pivotal Phase III trials suggest that NVA237 is safe and well tolerated in patients with moderate to severe COPD, and provides rapid and sustained improvements in lung function. Further, these changes are associated with statistically and clinically meaningful improvements in dyspnea, health-related quality of life, and exercise tolerance. Treatment with NVA237 also results in a significant reduction in risk of exacerbations and the need for rescue medication, and has been comparable with tiotropium with respect to safety and efficacy outcomes. Finally, emerging data indicate that NVA237 is efficacious both as monotherapy and in combination with indacaterol.Keywords: glycopyrronium bromide, NVA237, chronic obstructive pulmonary disease, inhaled long-acting bronchodilators

  6. Feasibility and market potential of protein determination of wheat using californium-252

    International Nuclear Information System (INIS)

    Roberts, T.C. Jr.; Eckhoff, N.D.; Clack, R.W.; Roberts, T.C. Sr.

    1976-01-01

    To evaluate the feasibility of protein determination by capture gamma-ray analysis using californium-252 neutrons, an in-situ protein analysis system for use by grain handlers has been examined. Three 227 kilogram (approximately) lots of wheat were used to determine the amount of nitrogen present. Protein analyses by the Kjeldahl method were obtained from samples taken before and after the capture gamma-ray analyses. The 5.267-MeV gamma-ray was selected for use in this study as a compromise between efficiency and interference from other elements. The associated counting equipment was a multichannel analyzer with pulse shaping electronic and analysis computing equipment. A linear regression program was used to compare the regions of interest to the Kjeldahl protein averages. The counts composing each peak were summed and normalized using the total count of the hydrogen peak. The normalized nitrogen percentages indicate a significant correlation between the spectral regions and the Kjeldahl analyses. To a first approximation, the value of wheat is the wheat protein. At the present time, protein testing of wheat is destructive, cumbersome, and time-consuming as compared to the potential for capture gamma-ray analysis testing. Assuming that such a protein analysis unit can analyze 42 tonne of wheat per hour, over 120 units would be needed to monitor one-half the U.S. annual wheat production. A 0.5% improvement in processor realizations and grain throughput value of $167.00 per tonne will result in a projected savings of $150,000 per year per unit

  7. 48 CFR 2452.237-75 - Clearance of contractor personnel.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Clearance of contractor... Clauses 2452.237-75 Clearance of contractor personnel. As prescribed in 2437.110(e), insert the following clause in solicitations and contracts. Clearance of Contractor Personnel (OCT 1999) (a) General. This...

  8. Sorption of 237Pu by the diatom Asterionella formosa

    International Nuclear Information System (INIS)

    Conway, H.L.; Wahlgren, M.A.; Peterson, N.; Nelson, D.M.

    1976-01-01

    Knowledge of the behavior of the man-made radionuclide plutonium within aquatic environments is of fundamental importance in assessing its potential hazards and ecological impact. The sorption of plutonium by phytoplankton and other algae is the dominant factor in the biological transport of plutonium in the aquatic environment, and it has been suggested that sorption by phytoplankton may be responsible for the seasonal loss of plutonium from the epilimnion of Lake Michigan. A unialgal diatom culture was spiked with 237 Pu tracer solution in an attempt to simulate the behavior of fallout plutonium observed in field studies. The results were encouraging in that the 237 Pu in the filtered lake water medium exhibited strongly anionic properties similar to fallout plutonium in Lake Michigan, with limited sorption on container walls. The purpose of the present study was to extend the investigations of the sorption of plutonium by phytoplankton in a controlled environment using continuous culture techniques

  9. Manganese determination om minerals by activation analysis, using the californium-252 as a neutron source

    International Nuclear Information System (INIS)

    Cardoso, Antonio

    1976-01-01

    Neutron Activation Analysis, using a Californium-252 neutron source, has been applied for the determination of manganese in ores such as pyrolusite, rodonite (manganese silicate)' and blending used in dry-batteries The favorable nuclear properties of manganese, such as high thermal neutron cross-section for the reaction 55 Mn (n.gamma) 56 Mn, high concentration of manganese in the matrix and short half - life of 56 Mn, are an ideal combination for non-destructive analysis of manganese in ores. Samples and standards of manganese dioxide were irradiated for about 20 minutes, followed by a 4 to 15 minutes decay and counted in a single channel pulse-height discrimination using a NaI(Tl) scintillation detector. Counting time was equal to 10 minutes. The interference of nuclear reactions 56 Fe(n,p) 56 Mn and 59 Co (n, α) 56 were studied, as well as problems in connection with neutron shadowing during irradiation, gamma-rays attenuation during counting and influence of granulometry of samples. One sample,was also analysed by wet-chemical method (sodium bismuthate) in order to compare results. As a whole, i t was shown that the analytical method of neutron activation for manganese in ores and blending, is a method simple, rapid and with good precision and accuracy. (author)

  10. A Single Recessive Mutated Gene (Sd237-1) Controlling Semi-Dwarf Plant Stature of Rice

    International Nuclear Information System (INIS)

    Sobrizal

    2009-01-01

    Dwarfism is a valuable trait in crop breeding, because it increases lodging resistance and decreases damages due to wind and rain. During the course of this study, a semi-dwarf mutant was successfully induced through 200 Gy gamma ray irradiated KI 237 seeds. KI 237 is a pure line with high yield potency, developed through an Indica-Japonica cross of IR36 / Koshihikari. The selected semi-dwarf plant reached 60 - 62 % of plant height of original plant KI 237 at the mature stage. The length of inter nodes, panicle, and seed were also compared between these two plants. The retardation of the 1 st (uppermost) inter nodes was 24 %, moreover, the retardation of panicle and seed length were only 10 % and 2 %, respectively. The elongation pattern of the inter nodes in this mutant was almost the same as sd1 (Dee-geo-woo-gen), the original parent of the first release modern rice variety, but their performances were different. Based on the segregation analysis in M 2 and M 3 generation it was concluded that this mutant was controlled by a single recessive mutated gene. This gene was designated as sd 237-1 . This mutant should be useful as a genetic resource for the improvement of KI 237 line through back-cross breeding as well as be developed further in breeding program directly to be a new high yielding mutant variety. (author)

  11. 48 CFR 237.7101 - Solicitation provisions and contract clauses.

    Science.gov (United States)

    2010-10-01

    ... contracts for laundry and dry cleaning services to be provided on a count-of-articles basis. (d) Use the clause at 252.237-7015, Loss or Damage (Weight of Articles), in solicitations and contracts for laundry... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Solicitation provisions...

  12. Role of transitional levels in 237Np (γ,f): Perspectives for studying highly deformed systems

    International Nuclear Information System (INIS)

    Arruda-Neto, J. D. T.; Mesa, J.; Garcia, F.; Rodriguez, O.; Geraldo, L. P.; Garcia, C.; Guzman, F.; Rodrigues, T. E.; Shtejer, K.; Semmler, R.

    2006-01-01

    The transition levels at the top of the two 237 Np fission barriers were obtained for the first time by means of the so-called semimicroscopic combined method, which we have developed and implemented. To overcome the difficulties in dealing with large nuclear deformations, we used our developed BARRIER code, which calculates single-particle spectra in a deformed Woods-Saxon potential using a coordinate system based on Cassini ovaloids as nuclear shape parametrization. The results enabled us to describe the experimentally observed near-barrier photofission cross-section structures for 237 Np, as well as a subbarrier shelf, the latter being consistently interpreted in terms of the accumulation of levels at the top of the inner and outer double fission barrier of 237 Np

  13. Field study of the migration of 237Np, 238Pu and 241Am in a weak loess aquifer

    International Nuclear Information System (INIS)

    Liu, C.L.; Wang, Z.M.; Li, S.S.; Yang, Y.E.; Li, B.; Jiang, H.; Jiang, L.; Wang, L.; Li, D.

    2004-01-01

    The migration of 237 Np, 238 Pu and 241 Am in a weak loess aquifer was investigated in-situ in an Underground Research Facility. Quartz containing 237 Np, 238 Pu, 241 Am and 3 H was introduced into the aquifer with a stainless steel tube. The local water flow in the aquifer was monitored using a 3-dimensional sampling system. The contaminated area of the aquifer was obtained wholly with the help of a pre-installed stainless steel frame and cut into small pieces (samples) 3-dimensionally and analyzed. 3 H in the water samples was determined with a liquid scintillation analyzer (Tri-Camb 2250). Radioactivity of 237 Np and 241 Am in the soil samples were determined with a low energy photon detector (HPGe), 238 Pu was analyzed with a low background αandβ detector after chemical separation. The result of the 3-year experiment indicated that 237 Np, 238 Pu and 241 Am were strongly absorbed by the loess aquifer. The retardation factor of 237 Np in the loess aquifer was 1.54 x 10 4 . (author)

  14. 29 CFR 779.237 - Enterprise engaged in commerce or in the production of goods for commerce.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Enterprise engaged in commerce or in the production of goods for commerce. 779.237 Section 779.237 Labor Regulations Relating to Labor (Continued) WAGE AND... commerce or in the production of goods for commerce. Under section 3(s) the “enterprise” to be covered must...

  15. The 'overlooked trio' of hypothetical terrorist nuclear weapons - reactor grade plutonium, neptunium-237 and tritium

    International Nuclear Information System (INIS)

    Sholly, S.

    2002-01-01

    Full text: Considerations revolving around physical protection of nuclear material are quite commonly and naturally focused on protecting weapons-grade plutonium (WGPu) and highly enriched uranium (HEU) from theft and diversion. These two materials are the center of attention because of their well-known (and demonstrated) potential for use in first-generation nuclear explosive devices of which potential terrorists are widely thought to be capable. They are also the center of attention because of retirements of these materials from military use as the Russian Federation and the United States reduce the number of nuclear weapons in their arsenals. Three other materials - an 'overlooked trio' - must also be borne in mind within this context: (1) reactor-grade plutonium (RGPu); (2) neptunium-237 (Np-237); and (3) tritium (H-3). Although there are still some authorities who either contend that RGPu cannot be used in a nuclear explosive or that there are (for a terrorist) insurmountable difficulties in doing so, the knowledgeable scientific and technical community, recognizes the potential utility of RGPu for hypothetical terrorist nuclear devices. A much smaller community of experts recognizes the usefulness of Np-237 for nuclear devices, but Np-237 is as straight-forwardly and easily usable as HEU and similarly abundant (but not often in separated form). Tritium can be used (with a modest increase in design sophistication) in a conventional first-generation nuclear device with any of the weapons-usable materials (WGPu, HEU, RGPu or Np-237) to increase the yield and/or increase the reliability of a non-fizzle yield. Given the presence of RGPu and Np-237 in abundant quantities in spent commercial reactor fuel, widely available knowledge of how to separate these materials, and a world-wide total of more than 400 nuclear power plants, spent reactor fuel also requires stringent controls. This is especially true of old spent fuel which has far less radiation dose

  16. Distribution of global fallout sup 237 Np, Pu isotopes, and sup 241 Am in lake and sea sediments

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Masayoshi; Yamauchi, Y; Chatani, K; Komura, K; Ueno, Kaoru; Sakanoue, Masanobu [Kanazawa Univ., Ishikawa (Japan). Low Level Radioactivity Lab.; Igarashi, Syuiti [Fukui Prefectural Inst. of Public Health (Japan)

    1991-01-01

    In order to investigate the sedimentary behaviour of neptunium, {sup 237}Np together with Pu isotopes and {sup 241}Am were measured for the sediment cores collected from Lake Mikata (freshwater), from Lake Kugushi (brakish water) and from Nyu Bay (sea water). In all sediment core samples {sup 237}Np was detected, and its concentrations were far below those of {sup 239,240}Pu and {sup 241}Am measured for the same samples. Inventories of {sup 237}Np in the lakes were estimated to be 0.53, 0.29 and 0.34 MBq/km{sup 2}, respectively. The activity ratios of {sup 237}Np/{sup 239,240}Pu, except for Lake Mikata, are two or three times lower than the value of 0.3-0.4% observed for surface soils of 0-20 cm depth, suggesting that Np is more soluble compared with Pu. (author) 21 refs.; 6 figs.; 3 tabs.

  17. Determination of traces of 237Np in environmental samples by ICP-MS after separation using TOA extraction chromatography

    International Nuclear Information System (INIS)

    Ji, Y.Q.; Li, J.Y.; Luo, S.G.; Wu, T.; Liu, J.L.

    2001-01-01

    A simple, rapid, cost-efficient, and robust method for separation of 237 Np with an extraction chromatographic column (TOA: tri-n-octylamine on Teflon powder) is outlined in detail and further improved for direct ICP-MS analysis. The column efficiently retained 237 Np in 2 mol L -1 HNO 3 medium and all of the 237 Np was easily eluted with 0.02 mol L -1 oxalic acid in 0.16 mol L -1 HNO 3 at 95 C. The separated solutions were free from most matrix elements and were aspirated into the ICP-MS directly. The decontamination factor for 238 U is more than 10 4 . The instrumental detection limit for 237 Np was 0.46 pg mL -1 , which corresponds to 1.2 x 10 -5 Bq mL -1 . The method is more rapid than traditional radiometric techniques. It is also considered to be more suitable for environmental monitoring than existing methods based on TOA. (orig.)

  18. Determination of traces of 237Np in environmental samples by ICP-MS after separation using TOA extraction chromatography.

    Science.gov (United States)

    Ji, Y Q; Li, J Y; Luo, S G; Wu, T; Liu, J L

    2001-09-01

    A simple, rapid, cost-efficient, and robust method for separation of 237Np with an extraction chromatographic column (TOA: tri-n-octylamine on Teflon powder) is outlined in detail and further improved for direct ICP-MS analysis. The column efficiently retained 237Np in 2 mol L(-1) HNO3 medium and all of the 237Np was easily eluted with 0.02 mol L(-1) oxalic acid in 0.16 mol L(-1) HNO3 at 95 degrees C. The separated solutions were free from most matrix elements and were aspirated into the ICP-MS directly. The decontamination factor for 238U is more than 10(4). The instrumental detection limit for 237Np was 0.46 pg mL(-1), which corresponds to 1.2 x 10(-5) Bq mL(-1). The method is more rapid than traditional radiometric techniques. It is also considered to be more suitable for environmental monitoring than existing methods based on TOA.

  19. Efficacy and safety of once-daily NVA237 in patients with moderate-to-severe COPD: the GLOW1 trial

    Directory of Open Access Journals (Sweden)

    D'Urzo Anthony

    2011-12-01

    Full Text Available Abstract Background NVA237 is a once-daily dry-powder formulation of the long-acting muscarinic antagonist glycopyrronium bromide in development for the treatment of chronic obstructive pulmonary disease (COPD. The glycopyrronium bromide in COPD airways clinical study 1 (GLOW1 evaluated the efficacy, safety and tolerability of NVA237 in patients with moderate-to-severe COPD. Methods Patients with COPD with a smoking history of ≥ 10 pack-years, post-bronchodilator forced expiratory volume in 1 second (FEV1 1/forced vital capacity 1 antagonists permitted in patients stabilized on them prior to study entry. The primary outcome measure was trough FEV1 at Week 12. Results A total of 822 patients were randomized to NVA237 (n = 552 or placebo (n = 270. Least squares mean (± standard error trough FEV1 at Week 12 was significantly higher in patients receiving NVA237 (1.408 ± 0.0105 L, versus placebo (1.301 ± 0.0137 L; treatment difference 108 ± 14.8 mL, p 1 were apparent at the end of Day 1 and sustained through Week 26. FEV1 was significantly improved in the NVA237 group versus placebo throughout the 24-hour periods on Day 1 and at Weeks 12 and 26, and at all other visits and timepoints. Transition dyspnoea index focal scores and St. George's Respiratory Questionnaire scores were significantly improved with NVA237 versus placebo at Week 26, with treatment differences of 1.04 (p Conclusions Once-daily NVA237 was safe and well tolerated and provided rapid, sustained improvements in lung function, improvements in dyspnoea, and health-related quality of life, and reduced the risk of exacerbations and the use of rescue medication. Trial registration ClinicalTrials.gov: NCT01005901

  20. Np-237 incineration study in various beams in ADS setup QUINTA

    Directory of Open Access Journals (Sweden)

    Kilim Stanisław

    2018-03-01

    Full Text Available Neptunium-237 samples were irradiated in a spallation neutron field produced in accelerator-driven system (ADS setup QUINTA. Five experiments were carried out on the accelerators at the JINR in Dubna - one in carbon (C6+, three in deuteron, and one in a proton beam. The energy in carbon was 24 GeV, in deuteron 2, 4 and 8 GeV, respectively, and 660 MeV in the proton beam. The incineration study method was based on gamma-ray spectrometry. During the analysis of the spectra several fission products and one actinide were identified. Fission product activities yielded the number of fissions. The actinide (Np-238, a result of neutron capture by Np-237, yielded the number of captures. The main goal of this work was to find out if and how the incineration rate depended on parameters of the accelerator beam.

  1. 'n Nota oor die vertaling van Jeremia 2:37 ("Met jou hande op jou hoof"

    Directory of Open Access Journals (Sweden)

    H.F. Stander

    1998-08-01

    Full Text Available A note on the translation of Jeremiah 2:37 ("With your hands on your head" In Jeremiah 2:37 God says to Israel: "You will leave that place (= Egypt with your hands upon your head". In this article various Bible translations and commentaries are scrutinized to determine how modem exegetes interpret this phrase. Thereafter the author discusses Egyptian depictions of mourners in funeral processions with their hands on their heads. He shows how an exploration of Egyptian Art can contribute to a better understanding of Jeremiah 2:37. This study also shows that the two dynamic Afrikaans translations of the Bible ("Die Lewende Bybel" and "Die Nuwe Afrikaanse Vertaling" are wide off the mark in their interpretation of the phrase "with your hands on your head". The author also argues that exegetes should not only rely on written texts when they study the ancient world in which the Scriptures originated, but that they should also explore works of art.

  2. 40 CFR 81.237 - Northeast Georgia Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Northeast Georgia Intrastate Air... Air Quality Control Regions § 81.237 Northeast Georgia Intrastate Air Quality Control Region. The Northeast Georgia Intrastate Air Quality Control Region consists of the territorial area encompassed by the...

  3. A novel Meloidogyne graminicola effector, MgMO237, interacts with multiple host defence-related proteins to manipulate plant basal immunity and promote parasitism.

    Science.gov (United States)

    Chen, Jiansong; Hu, Lili; Sun, Longhua; Lin, Borong; Huang, Kun; Zhuo, Kan; Liao, Jinling

    2018-02-27

    Plant-parasitic nematodes can secrete effector proteins into the host tissue to facilitate their parasitism. In this study, we report a novel effector protein, MgMO237, from Meloidogyne graminicola, which is exclusively expressed within the dorsal oesophageal gland cell and markedly up-regulated in parasitic third-/fourth-stage juveniles of M. graminicola. Transient expression of MgMO237 in protoplasts from rice roots showed that MgMO237 was localized in the cytoplasm and nucleus of the host cells. Rice plants overexpressing MgMO237 showed an increased susceptibility to M. graminicola. In contrast, rice plants expressing RNA interference vectors targeting MgMO237 showed an increased resistance to M. graminicola. In addition, yeast two-hybrid and co-immunoprecipitation assays showed that MgMO237 interacted specifically with three rice endogenous proteins, i.e. 1,3-β-glucan synthase component (OsGSC), cysteine-rich repeat secretory protein 55 (OsCRRSP55) and pathogenesis-related BetvI family protein (OsBetvI), which are all related to host defences. Moreover, MgMO237 can suppress host defence responses, including the expression of host defence-related genes, cell wall callose deposition and the burst of reactive oxygen species. These results demonstrate that the effector MgMO237 probably promotes the parasitism of M. graminicola by interacting with multiple host defence-related proteins and suppressing plant basal immunity in the later parasitic stages of nematodes. © 2018 BSPP AND JOHN WILEY & SONS LTD.

  4. Long-term effects of an intracavitary treatment with californium-252 on normal tissue. [Swine, /sup 226/Ra

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, M.F.; Beamer, J.L.; Mahony, T.D.; Cross, F.T.; Lund, J.E.; Endres, G.W.R.

    1976-01-01

    About one hundred fifty swine were exposed to either radium-226 or californium-252 sources in the uterine cervix to determine an RBE for both acute and long-term effects. That value for early changes in the tissues at risk in the treatment of cervical cancer was between 6.2 and 6.8. The incidence of complications increased with time after exposure, especially among animals treated with /sup 252/Cf. Analysis of rectal injury showed that ulceration occurred frequently within a year postexposure at doses between 1600 and 2400 rad calculated at 2 cm lateral to the source midline. Fat necrosis and smooth muscle atrophy, resulting in a local rectal stricture, were delayed changes observed in some animals. The lower ureter was the site for a greater frequency of complications than the GI tract. Ureteral stricture often occurred at doses of 1200 rad from /sup 252/Cf and 7000 rad from /sup 226/Ra. Observation of delayed effects in the uterine-cervix in animals held up to 4 years postexposure indicate that the RBE for /sup 252/Cf may be increased to a value as high as 18, while repair may have even decreased it to about 5.6 in the rectum. Fifty swine are still being observed for long-term effects after doses above 800 rad from /sup 252/Cf and 5000 rad from /sup 226/Ra.

  5. Photofission Cross Sections for 237Np in the Energy Interval from 5.27 to 10.83 MeV

    International Nuclear Information System (INIS)

    Geraldo, L.P.; Semmler, R.; Goncalez, O. L.; Mesa, J.; Arruda-Neto, J.D.T.; Garcia, F.; Rodriguez, O.

    2000-01-01

    Photofission cross sections for 237 Np have been measured as a function of energy, in the interval from 5.27 to 10.83 MeV. The gamma-ray spectra were those produced by thermal neutron capture, in 30 different target materials, at a tangential beam hole of the Instituto de Pesquisas Energeticas e Nucleares IEA-R1 2-MW research reactor. The set of experimental data has been unfolded employing least-squares methods and the covariance matrix methodology. The determined photofission cross sections for 237 Np, together with the complete correlation matrix for the involved errors, are presented and are compared with previous measurements reported in the literature. A statistical calculation for the 237 Np photofission cross sections was performed, and the results are compared with the experimental data

  6. Fast and efficient charge breeding of the Californium rare isotope breeder upgrade electron beam ion source

    International Nuclear Information System (INIS)

    Ostroumov, P. N.; Barcikowski, A.; Dickerson, C. A.; Perry, A.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G. P.; Pikin, A. I.

    2015-01-01

    The Electron Beam Ion Source (EBIS), developed to breed Californium Rare Isotope Breeder Upgrade (CARIBU) radioactive beams at Argonne Tandem Linac Accelerator System (ATLAS), is being tested off-line. A unique property of the EBIS is a combination of short breeding times, high repetition rates, and a large acceptance. Overall, we have implemented many innovative features during the design and construction of the CARIBU EBIS as compared to the existing EBIS breeders. The off-line charge breeding tests are being performed using a surface ionization source that produces singly charged cesium ions. The main goal of the off-line commissioning is to demonstrate stable operation of the EBIS at a 10 Hz repetition rate and a breeding efficiency into single charge state higher than 15%. These goals have been successfully achieved and exceeded. We have measured (20% ± 0.7%) breeding efficiency into the single charge state of 28+ cesium ions with the breeding time of 28 ms. In general, the current CARIBU EBIS operational parameters can provide charge breeding of any ions in the full mass range of periodic table with high efficiency, short breeding times, and sufficiently low charge-to-mass ratio, 1/6.3 for the heaviest masses, for further acceleration in ATLAS. In this paper, we discuss the parameters of the EBIS and the charge breeding results in a pulsed injection mode with repetition rates up to 10 Hz

  7. Transmutation of actinide 237Np with a fusion reactor and a hybrid reactor

    International Nuclear Information System (INIS)

    Feng, K.M.; Huang, J.H.

    1994-01-01

    The use of fusion reactors to transmute fission reactor wastes to stable species is an attractive concept. In this paper, the feasibility of transmutation of the long-lived actinide radioactive waste Np-237 with a fusion reactor and a hybrid reactor has been investigated. A new waste management concept of burning HLW (High Level Waste), utilizing released energy and converting Np-237 into fissile fuel Pu-239 through transmutation has been adopted. The detailed neutronics and depletion calculation of waste inventories was carried out with a modified version of one-dimensional neutron transport and burnup calculation code system BISON1.5 in this study. The transmutation rate of Np with relationship to neutron wall loading, Pu and Np with relationship to neutron wall load, Pu and Np concentration in the transmutation zone have been explored as well as relevant results are also given

  8. Neutron flux characterization of californium-252 Neutron Research Facility at the University of Texas - Pan American by nuclear analytical technique

    Science.gov (United States)

    Wahid, Kareem; Sanchez, Patrick; Hannan, Mohammad

    2014-03-01

    In the field of nuclear science, neutron flux is an intrinsic property of nuclear reaction facilities that is the basis for experimental irradiation calculations and analysis. In the Rio Grande Valley (Texas), the UTPA Neutron Research Facility (NRF) is currently the only neutron facility available for experimental research purposes. The facility is comprised of a 20-microgram californium-252 neutron source surrounded by a shielding cascade containing different irradiation cavities. Thermal and fast neutron flux values for the UTPA NRF have yet to be fully investigated and may be of particular interest to biomedical studies in low neutron dose applications. Though a variety of techniques exist for the characterization of neutron flux, neutron activation analysis (NAA) of metal and nonmetal foils is a commonly utilized experimental method because of its detection sensitivity and availability. The aim of our current investigation is to employ foil activation in the determination of neutron flux values for the UTPA NSRF for further research purposes. Neutron spectrum unfolding of the acquired experimental data via specialized software and subsequent comparison for consistency with computational models lends confidence to the results.

  9. Use of the electrodeposition technique in the preparation of samples of 237Np and its determination by alpha spectrometry

    International Nuclear Information System (INIS)

    Mertzig, W.; Matsuda, H.T.; Araujo, B.F. de; Araujo, J.A. de.

    1981-05-01

    The electroplating technique to prepare 237 Np source and its determination by alpha spectrometry is presented. The samples were prepared using a lucite-eletrolitic cell manufactured at IPEN, specially to trace amounts of actinides. A polished brass disk coated with Ni film has been used as cathodo and a fixed Pt wire as anode. The electroplated samples were alpha counted using a surface barrier detector. The optimum conditions to obtain the quantitative deposition of 237 Np have been achieved by studying the effects of some parameters as current density, pH and concentration of eletrolitic solution and time of eletrodeposition, using a carrier technique. After preliminary purification, the method is applied to control trace amounts of 237 Np in the Purex process solutions. (Author) [pt

  10. 242Pu as tracer for simultaneous determination of 237Np and 239,240Pu in environmental samples

    DEFF Research Database (Denmark)

    Chen, Q.J.; Dahlgaard, H.; Nielsen, S.P.

    2002-01-01

    A procedure has been developed using Pu-242 as tracer for simultaneous determination of Np-237 and Pu-239,Pu-240 in environmental samples. The validity of the method has been demonstrated by ICPMS and alpha-spectroscopy for up to 10 gram soil and sediment, seawater up to 200 litres. The paper...... from Np and Pu) R-before/R-after = 1.004 +/- 3.3% (S.D n = 20) and 1 litre seawater R-before/R-after = 1.019+/-1.9% (S.D., n = 12). Results from the intercomparison samples LAEA-135, LAEA-381 and from environmental samples are presented....... describes a suitable chemical procedure for Np and Pu including a quantitative pre-concentration of neptunium and plutonium, preparation of Np4+ and Pu4+, NP(NO3)(6)(2-) and Pu(NO3)(6)(2-), The ratio of Np-237/Pu-242 (or Np-237/Pu-239) before and after the procedure has been determined using 10 g soil (free...

  11. Transfer of 241Am and 237Pu from euphausiid moults to a carbonate-rich marine sediment

    International Nuclear Information System (INIS)

    Hargrave, B.T.

    1986-01-01

    Concentrations of 241 Am and 237 Pu adsorbed onto moulted exoskeletons from the euphausiid Meganyctiphanes norvegica decreased exponentially with 50% retention times of 3-7 d when moults were incubated in filtered seawater with small amounts of carbonate-rich sediment. Over 95% of sediment weight was present as -2 ) was greatest in the medium-fine sand fraction which had the highest carbonate content. These particles constituted -2 surface: atoms μm -3 in solution) was 10 3 -10 4 times higher than similar quotients for 241 Am and 237 Pu sorbed to surfaces of organic particles are transferred to sediments. (author)

  12. 50 CFR 23.7 - What office do I contact for CITES information?

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false What office do I contact for CITES... FAUNA AND FLORA (CITES) Introduction § 23.7 What office do I contact for CITES information? Contact the following offices to receive information about CITES: Type of information Office to contact (a) CITES...

  13. Savannah River Plant 200 Area technical manual. Part SP. Processing of Np/sup 237/ and Pu/sup 238/

    Energy Technology Data Exchange (ETDEWEB)

    Hill, A.J. (comp.)

    1963-01-03

    This manual covers the technology involved in the 200 Area process for the recovery of Np/sup 237/ from certain aqueous waste streams in the separations plants, for the recovery of NP/sup 237/ and Pu/sup 238/ from irradiated NpO/sub 2/-Al slugs and for the fabrication of NpO/sub 2/-Al slugs. The manual contains sections on the fundamental chemistry, the primary recovery of Np by ion exchange, the decontamination of Np by ion exchange, the processing of NpO/sub 2/-Al targets, the separation and purification of Np/sup 237/ and Pu/sup 238/, the finishing of Np, the preparation of NpO/sub 2/, the disposal of spent resin, and the safety aspects of the handling of hydrazine. The section on the fabrication of NpO/sub 2/-Al slugs will be added later. 76 refs., 22 figs.

  14. The Synergistic Effect of Valsartan and LAF237 [(S-1-[(3-Hydroxy-1-AdamantylAmmo]acetyl-2-Cyanopyrrolidine] on Vascular Oxidative Stress and Inflammation in Type 2 Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Min Shen

    2012-01-01

    Full Text Available Aim. To investigate the combination effects and mechanisms of valsartan (angiotensin II type 1 receptor blocker and LAF237 (DPP-IV inhibitor on prevention against oxidative stress and inflammation injury in db/db mice aorta. Methods. Db/db mice (n=40 were randomized to receive valsartan, LAF237, valsartan plus LAF237, or saline. Oxidative stress and inflammatory reaction in diabetic mice aorta were examined. Results. Valsartan or LAF237 pretreatment significantly increased plasma GLP-1 expression, reduced apoptosis of endothelial cells isolated from diabetic mice aorta. The expression of NAD(PH oxidase subunits also significantly decreased resulting in decreased superoxide production and ICAM-1 (fold change: valsartan : 7.5 ± 0.7, P<0.05; LAF237: 10.2 ± 1.7, P<0.05, VCAM-1 (fold change: valsartan : 5.2 ± 1.2, P<0.05; LAF237: 4.8 ± 0.6, P<0.05, and MCP-1 (fold change: valsartan: 3.2 ± 0.6, LAF237: 4.7 ± 0.8; P<0.05 expression. Moreover, the combination treatment with valsartan and LAF237 resulted in a more significant increase of GLP-1 expression. The decrease of the vascular oxidative stress and inflammation reaction was also higher than monotherapy with valsartan or LAF237. Conclusion. These data indicated that combination treatment with LAF237 and valsartan acts in a synergistic manner on vascular oxidative stress and inflammation in type 2 diabetic mice.

  15. 27 CFR 24.237 - Spirits added to juice or concentrated fruit juice.

    Science.gov (United States)

    2010-04-01

    ... AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.237 Spirits added to juice or... fruit juice to which spirits have been added will be included in the appropriate tax class of any wine inventory and will be properly identified. Juice or concentrated juice to which wine spirits are added will...

  16. Identification of Nilsson orbitals in the superdeformed minimum of 237Pu

    International Nuclear Information System (INIS)

    Morgan, Thomas James

    2008-01-01

    In this thesis, a spectroscopy experiment in the second minimum of the double humped fission barrier of 237 Pu is presented, in which, for the first time, single - particle states for a neutron - rich shape isomer with odd neutron number were identified and characterised by their Nilsson quantum numbers. While rotational ( 236f U and 240f Pu) and vibrational excitations ( 240f Pu) had already been identified earlier in the even-even neighbouring nuclei, now the fission isomers in 237 Pu (t 1/2 =115 ns/1.12 μs) were investigated in a γ-spectroscopy experiment at the Cologne Tandem accelerator. Using the 235 U(α,2n) reaction with a pulsed R beam, states in the second minimum were populated. Following the prompt decay of excited states into the ground states of the two shape isomers, the nucleus decays with its halflife, the resulting fission fragments were detected in a specially built 4π parallel plate detector. The extremely rare isomeric γ decays were measured in coincidence with the fission fragments using the highly efficient MINIBALL spectrometer. The background-subtracted γ-ray spectrum was disentangled into contributions from the two shape isomers and 9 excited rotational bands were identified built on the ground states of the two isomers. The ground state spins of the two shape isomers were determined to be I=5/2 (115 ns isomer) and I=9/2 (1120 ns isomer). From the 149 identified γ transitions, independent level schemes were constructed for the two fission isomers in 237 Pu. The consistency of these level schemes was supported by the connecting γ transitions between rotational bands. Furthermore, both level schemes could be combined to a common level scheme, in which the ground state of the long-lived 9/2 isomer was placed 54.0(3) keV above the ground state of the short-lived 5/2 isomer. The resulting level scheme was compared to Hartree-Fock-Bogolyubov single-particle calculations, Nilsson model and Woods-Saxon potential calculations. This

  17. LOFT CIS analysis 4''-WH-237-E inside containment penetration S-17B

    International Nuclear Information System (INIS)

    Nitzel, M.E.

    1978-01-01

    The stress analysis performed on the 4''-WH-237-E piping system inside containment penetration S-17B is presented. Deadweight, thermal expansion, and seismic loads were considered. Results of this analysis show that the subject piping system will meet ASME Code, Section III, Class 2 requirements

  18. First experiments on transmutation studies of iodine-129 and neptunium-237 using relativistic protons of 3.7 GeV

    International Nuclear Information System (INIS)

    Krivopustov, M.I.; Adam, J.; Bradnova, V.

    1997-01-01

    First experiments on the transmutation of long-lived 129 I and 237 Np using relativistic protons of 3.7 GeV are described. Relativistic protons generate in extended Pb-targets substantial neutron fluences. These neutrons get moderated in paraffin and are used for transmutation as follows: 129 (n, γ) 130 I(β - ) → 130 Xe(stable) and 237 Np(n, γ) 238 Np(β - ) →. The isotopes 130 I (T 1/2 =12.36 h) and 238 Np (T 1/2 =2.117 days) were identified radiochemically. One can estimate the transmutation cross section (n, γ) in the given neutron field as σ( 129 I(n, γ))=(10±2)b and σ( 237 Np(n, γ))=(140±30)b. The experiments were carried out in November 1996 at the Synchrophasotron, Laboratory of High Energies (LHE), Dubna, Russia

  19. The Synergistic Effect of Valsartan and LAF237 [(S)-1-[(3-Hydroxy-1-Adamantyl)Ammo]acetyl-2-Cyanopyrrolidine] on Vascular Oxidative Stress and Inflammation in Type 2 Diabetic Mice

    Science.gov (United States)

    Shen, Min; Sun, Dongdong; Li, Weijie; Liu, Bing; Wang, Shenxu; Zhang, Zheng; Cao, Feng

    2012-01-01

    Aim. To investigate the combination effects and mechanisms of valsartan (angiotensin II type 1 receptor blocker) and LAF237 (DPP-IV inhibitor) on prevention against oxidative stress and inflammation injury in db/db mice aorta. Methods. Db/db mice (n = 40) were randomized to receive valsartan, LAF237, valsartan plus LAF237, or saline. Oxidative stress and inflammatory reaction in diabetic mice aorta were examined. Results. Valsartan or LAF237 pretreatment significantly increased plasma GLP-1 expression, reduced apoptosis of endothelial cells isolated from diabetic mice aorta. The expression of NAD(P)H oxidase subunits also significantly decreased resulting in decreased superoxide production and ICAM-1 (fold change: valsartan : 7.5 ± 0.7, P valsartan : 5.2 ± 1.2, P valsartan: 3.2 ± 0.6, LAF237: 4.7 ± 0.8; P valsartan and LAF237 resulted in a more significant increase of GLP-1 expression. The decrease of the vascular oxidative stress and inflammation reaction was also higher than monotherapy with valsartan or LAF237. Conclusion. These data indicated that combination treatment with LAF237 and valsartan acts in a synergistic manner on vascular oxidative stress and inflammation in type 2 diabetic mice. PMID:22474415

  20. The inhalation of insoluble iron oxide particles in the sub-micron ranges. Part II - Plutonium-237 labelled aerosols

    International Nuclear Information System (INIS)

    Waite, D.A.; Ramsden, D.

    1971-10-01

    The results of a series of inhalation studies using iron oxide particles in the size range 0.1 to 0.3 um (count median diameter) are described. In this series the aerosols were labelled with plutonium 237. In vivo detection, excretion analysis and crude location studies were obtainable and the results compared to the earlier studies using chromium 51 labelled aerosols. Plutonium 237 can be considered as a simulator for plutonium 239 and attempts are made to extrapolate the results to the problem of the estimation of plutonium 239 in the human lung. (author)

  1. New experimental determination of the neutronic resonance parameters of {sup 237}Np below 500 eV; Nouvelle determination experimentale des parametres de resonances neutroniques de {sup 237}Np en dessous de 500 eV

    Energy Technology Data Exchange (ETDEWEB)

    Gressier, V

    1999-10-01

    For studies of future nuclear reactors dedicated to nuclear waste transmutation, an improvement of the accuracy of the neutron radiative capture cross section of {sup 237}Np appears necessary. In the framework of a collaboration between the Commissariat a l'Energie atomique (CEA) and Institute for Reference Materials and Measurement (IRMM, Geel, Bergium), a new determination of the resonance parameters of {sup 237}Np has been performed. Two types of experiments are carried out at GELINA, the IRMM pulsed neutron source, using the time of flight method: a transmission experiment which is related to the neutron total cross section and a capture experiment which gives the neutron radiative capture cross section. The resonance parameters presented in this work are extracted from the transmission data between 0 and 500 eV with the least square code REFIT, using the Reich-Moore formalism. In parallel, the Doppler effect is investigated. The commonly used free gas model appears inadequate below 20 eV for neptunium dioxide at room temperature. By the use of the program DOPUSH, which calculates the Doppler broadening with a harmonic crystal model according to Lamb's theory, we are able to produce abetter fit of the experimental data for the resonances of {sup 237}Np in NpO{sub 2} at low energy or temperatures. In addition to the resonance parameters, a study of their mean value and distribution is included in this work. (authors)

  2. Biokinetics of 237Np in two marine benthic invertebrates

    International Nuclear Information System (INIS)

    Guary, J.C.; Fowler, S.W.

    1976-01-01

    The long-lived alpha-emitting actinide 237 Np (T 1/2 = 2.2 x 10 6 y) enters the aquatic environment directly from nuclear testing and reprocessing plant wastes as well as indirectly by in situ generation from 241 Am. Earlier studies on 239 Np in the Columbia river ecosystem demonstrated that neptunium accumulated in aquatic species such as algae, sponges and insect larvae but was not detectable in higher trophic level organisms. Based on these findings and the fact that neptunium is chemically similar to the rare earth elements, it has been suggested that this actinide would not easily become incorporated into aquatic biota

  3. (237)Np(n,f) Cross Section: New Data and Present Status

    CERN Document Server

    Paradela, C; Carrapico, C; Eleftheriadis, C; Leeb, H; Calvino, F; Herrera-Martinez, A; Savvidis, I; Vlachoudis, V; Haas, B; Vannini, G; Le Naour, C; Gramegna, F; Wiescher, M; Pigni, M T; Audouin, L; Mengoni, A; Quesada, J; Becvar, F; Plag, R; Cennini, P; Mosconi, M; Duran, I; Rauscher, T; Couture, A; Capote, R; Sarchiapone, L; Vlastou, R; Domingo-Pardo, C; Dillmann, I; Pavlopoulos, P; Karamanis, D; Krticka, M; Jericha, E; Ferrari, A; Martinez, T; Trubert, D; Oberhummer, H; Karadimos, D; Plompen, A; Isaev, S; Terlizzi, R; Kaeppeler, F; Cortes, G; Cox, J; Voss, F; Pretel, C; Colonna, N; Berthoumieux, E; Vaz, P; Heil, M; Lopes, I; Lampoudis, C; Walter, S; Calviani, M; Gonzalez-Romero, E; Embid-Segura, M; Stephan, C; Igashira, M; Papachristodoulou, C; Aerts, G; Tavora, L; Berthier, B; Rudolf, G; Andrzejewski, J; Villamarin, D; Ferreira-Marques, R; Tain, J L; O'Brien, S; Gunsing, F; Reifarth, R; Perrot, L; Lindote, A; Neves, F; Poch, A; Kerveno, M; Rubbia, C; Koehler, P; Dahlfors, M; Wisshak, K; Salgado, J; Dridi, W; Ventura, A; Andriamonje, S; Assimakopoulos, P; Santos, C; Ferrant, L; Lozano, M; Patronis, N; Chiaveri, E; Guerrero, C; Kadi, Y; Vicente, M C; Praena, J; Baumann, P; Oshima, M; Rullhusen, P; Furman, W; David, S; Marrone, S; Tassan-Got, L; Cano-Ott, D; Pavlix, A; Alvarez-Velarde, F; Massimi, C; Mastinu, P; Pancin, J; Papadopoulos, C; Tagliente, G; Haight, R; Chepel, V; Kossionides, E; Badurek, G; Marganiec, J; Lukic, S; Tarrio, D; Alvarez, H

    2011-01-01

    In this document, we present the final result obtained at the n_TOF experiment; for the neutron-induced fission cross section of the (237)Np, from the fission threshold up to 1 GeV. The method applied to get tins result is briefly discussed. n_TOF data are compared to the last experimental measurements using other TOF facilities or the surrogate method, reported experiments performed with monoenergetic sources and the FISCAL systematic, including a discussion about the existing discrepancies.

  4. Transmutation of 129I, 237Np, 238Pu, 239Pu, and 241Am using ...

    Indian Academy of Sciences (India)

    Results of transmutation studies of 129I, 237Np, 238Pu, 239Pu and 241Am are presented. Keywords. ... J Adam et al. Table 1. Samples properties for 0.7 and 1 GeV experiments. ..... If we suppose that this conclusion is true also for ratios in ...

  5. 49 CFR 237.73 - Protection of bridges from over-weight and over-dimension loads.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Protection of bridges from over-weight and over... (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Capacity of Bridges § 237.73 Protection of bridges from over-weight and over-dimension loads. (a) Each track owner...

  6. Evaluation of nuclear data of 244Pu and 237Pu

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo; Konshin, V.A.

    1995-10-01

    The evaluation of nuclear data for 244 Pu and 237 Pu was made in the neutron energy region from 10 -5 eV to 20 MeV. For the both nuclides, the total, elastic and inelastic scattering, fission, capture, (n,2n) and (n,3n) reaction cross sections were evaluated on the basis of theoretical calculation. The resonance parameters were given for 244 Pu. The angular and energy distributions of secondary neutrons were also estimated for the both nuclides. The results were compiled in the ENDF-5 format and will be adopted in JENDL Actinoid File. (author)

  7. Transuranium element chalcogenides. Crystallochemistry and Moessbauer spectrometry of neptunium 237 chalcogenides

    International Nuclear Information System (INIS)

    Thevenin, T.; Pages, M.; Damien, D.

    1981-09-01

    To study actinide compounds , neptunium 237 has been studied by Moessbauer resonance. The different oxidation degrees of neptunium (7, 6, 5, 4 and 3) have a very important effect on isomeric displacements. In the study of chalcogenides, the isomeric displacement value of NpS 3 confirms the valency 4+ of neptunium in this compound. Results obtained with Np 3 S 5 show two valency state +3 and +4 in this compound. There is a good agreement with the two crystalline sites determined by crystallography [fr

  8. Identification of Nilsson orbitals in the superdeformed minimum of {sup 237}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Thomas James

    2008-03-31

    In this thesis, a spectroscopy experiment in the second minimum of the double humped fission barrier of {sup 237}Pu is presented, in which, for the first time, single - particle states for a neutron - rich shape isomer with odd neutron number were identified and characterised by their Nilsson quantum numbers. While rotational ({sup 236f}U and {sup 240f}Pu) and vibrational excitations ({sup 240f}Pu) had already been identified earlier in the even-even neighbouring nuclei, now the fission isomers in {sup 237}Pu (t{sub 1/2}=115 ns/1.12 {mu}s) were investigated in a {gamma}-spectroscopy experiment at the Cologne Tandem accelerator. Using the {sup 235}U({alpha},2n) reaction with a pulsed R beam, states in the second minimum were populated. Following the prompt decay of excited states into the ground states of the two shape isomers, the nucleus decays with its halflife, the resulting fission fragments were detected in a specially built 4{pi} parallel plate detector. The extremely rare isomeric {gamma} decays were measured in coincidence with the fission fragments using the highly efficient MINIBALL spectrometer. The background-subtracted {gamma}-ray spectrum was disentangled into contributions from the two shape isomers and 9 excited rotational bands were identified built on the ground states of the two isomers. The ground state spins of the two shape isomers were determined to be I=5/2 (115 ns isomer) and I=9/2 (1120 ns isomer). From the 149 identified {gamma} transitions, independent level schemes were constructed for the two fission isomers in {sup 237}Pu. The consistency of these level schemes was supported by the connecting {gamma} transitions between rotational bands. Furthermore, both level schemes could be combined to a common level scheme, in which the ground state of the long-lived 9/2 isomer was placed 54.0(3) keV above the ground state of the short-lived 5/2 isomer. The resulting level scheme was compared to Hartree-Fock-Bogolyubov single

  9. A study of the multipolar composition of the electrofission cross section of 237Np

    International Nuclear Information System (INIS)

    Paschoal, S.L.

    1987-01-01

    The electrofission cross section for 237 Np was measured over the energy range from 0,6 to 60,0 MeV. The multipolar composition of this cross section was investigated using the virtual photons formalism with three different techniques of analysis: unfolding and two versions of multiple parameter regression. (A.C.A.S.) [pt

  10. Osteosarcoma induction by plutonium-239, americium-241 and neptunium-237 : the problem of deriving risk estimates for man

    International Nuclear Information System (INIS)

    Taylor, D.M.

    1988-01-01

    Spontaneous bone cancer (osteosarcoma) represents only about 0.3% of all human cancers, but is well known to be inducible in humans by internal contamination with radium-226 and radium-224. plutonium-239, americium-241 and neptunium-237 form, or will form, the principal long-lived alpha particle emitting components of high activity waste and burnt-up nuclear fuel elements. These three nuclides deposit extensively in human bone and although, fortunately, no case of a human osteosarcoma induced by any of these nuclides is known, evidence from animal studies suggests that all three are more effective than radium-226 in inducing osteosarcoma. The assumption that the ratio of the risk factors, the number of osteosarcoma expected per 10000 person/animal Gy, for radium-226 and any other bone-seeking alpha-emitter will be independent of animal species has formed the basis of all the important studies of the radiotoxicity of actinide nuclides in experimental animals. The aim of this communication is to review the risk factors which may be calculated from the various animal studies carried out over the last thirty years with plutonium-237, americium-241 and neptunium-237 and to consider the problems which may arise in extrapolating these risk factors to homo sapiens

  11. Independent Yields of Kr and Xe Fragments at Photofission of Odd Nuclei ^{237}Np and ^{243}Am

    CERN Document Server

    Gangrsky, Yu P; Myshinskii, G V; Penionzhkevich, Yu E

    2004-01-01

    he independent yields of fragments Kr (A=89-93) and Xe (A=135-142) at photofission of odd nuclei 237Np and 243Am are presented. The experiments were performed using the bremsstrahlung of 25 MeV electrons on the microtron of FLNR, JINR. A technique was used that included the transportation of fragments which escaped from the target with the gas flow through a capillary and the condensation of inert gases in a cryostat at the temperature of liquid nitrogen. Kr and Xe isotopes were identified by the spectra of their daughter products. The mass number distributions of the independent yields of Kr and Xe isotopes and of the complementary fragments (Y and La at the photofission of ^{237}Np and Nb and Pr at the photofission of ^{243}Am) were obtained.

  12. Multimode approach to Am-241 and Np-237 fission induced by 660-MeV protons

    Czech Academy of Sciences Publication Activity Database

    Karapetyan, G. S.; Balabekyan, A. R.; Demekhina, N. A.; Adam, Jindřich

    2009-01-01

    Roč. 72, č. 6 (2009), s. 911-916 ISSN 1063-7788 R&D Projects: GA MŠk(CZ) LA08002 Institutional research plan: CEZ:AV0Z10480505 Keywords : FISSION * Am-241 * Np-237 Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.539, year: 2009

  13. Measurements of the neutron capture cross sections and incineration potentials of minor-actinides in high thermal neutron fluxes: Impact on the transmutation of nuclear wastes

    International Nuclear Information System (INIS)

    Bringer, O.

    2007-10-01

    This thesis comes within the framework of minor-actinide nuclear transmutation studies. First of all, we have evaluated the impact of minor actinide nuclear data uncertainties within the cases of 241 Am and 237 Np incineration in three different reactor spectra: EFR (fast), GT-MHR (epithermal) and HI-HWR (thermal). The nuclear parameters which give the highest uncertainties were thus highlighted. As a result of fact, we have tried to reduce data uncertainties, in the thermal energy region, for one part of them through experimental campaigns in the moderated high intensity neutron fluxes of ILL reactor (Grenoble). These measurements were focused onto the incineration and transmutation of the americium-241, the curium-244 and the californium-249 isotopes. Finally, the values of 12 different cross sections and the 241 Am isomeric branching ratio were precisely measured at thermal energy point. (author)

  14. Probing the dynamic interface between trimethylamine dehydrogenase (TMADH) and electron transferring flavoprotein (ETF) in the TMADH-2ETF complex: role of the Arg-alpha237 (ETF) and Tyr-442 (TMADH) residue pair.

    Science.gov (United States)

    Burgess, Selena G; Messiha, Hanan Latif; Katona, Gergely; Rigby, Stephen E J; Leys, David; Scrutton, Nigel S

    2008-05-06

    We have used multiple solution state techniques and crystallographic analysis to investigate the importance of a putative transient interaction formed between Arg-alpha237 in electron transferring flavoprotein (ETF) and Tyr-442 in trimethylamine dehydrogenase (TMADH) in complex assembly, electron transfer, and structural imprinting of ETF by TMADH. We have isolated four mutant forms of ETF altered in the identity of the residue at position 237 (alphaR237A, alphaR237K, alphaR237C, and alphaR237E) and with each form studied electron transfer from TMADH to ETF, investigated the reduction potentials of the bound ETF cofactor, and analyzed complex formation. We show that mutation of Arg-alpha237 substantially destabilizes the semiquinone couple of the bound FAD and impedes electron transfer from TMADH to ETF. Crystallographic structures of the mutant ETF proteins indicate that mutation does not perturb the overall structure of ETF, but leads to disruption of an electrostatic network at an ETF domain boundary that likely affects the dynamic properties of ETF in the crystal and in solution. We show that Arg-alpha237 is required for TMADH to structurally imprint the as-purified semiquinone form of wild-type ETF and that the ability of TMADH to facilitate this structural reorganization is lost following (i) redox cycling of ETF, or simple conversion to the oxidized form, and (ii) mutagenesis of Arg-alpha237. We discuss this result in light of recent apparent conflict in the literature relating to the structural imprinting of wild-type ETF. Our studies support a mechanism of electron transfer by conformational sampling as advanced from our previous analysis of the crystal structure of the TMADH-2ETF complex [Leys, D. , Basran, J. , Sutcliffe, M. J., and Scrutton, N. S. (2003) Nature Struct. Biol. 10, 219-225] and point to a key role for the Tyr-442 (TMADH) and Arg-alpha237 (ETF) residue pair in transiently stabilizing productive electron transfer configurations. Our work

  15. Numerical simulation of CALIBAN reactivity perturbation experiments using neptunium-237 samples

    International Nuclear Information System (INIS)

    Humbert, Philippe; Mechitoua, Boukhmes

    2003-01-01

    In order to contribute to the validation of nuclear data used in critical mass computation, reactivity perturbation experiments using 237 Np samples have been performed at CEA-Valduc using the fast pulsed reactor CALIBAN operated in continuous mode. In this paper we report these experiments together with the numerical calculations. The calculations were carried out using PANDA, a S N code developed at CEA-Bruyeres-le-Chatel for classic criticality and stochastic neutronics applications and with MCNP4C which is a commonly used Monte Carlo code. A good agreement was found between experimental and deterministic results. (author)

  16. Measurements of fast neutron-induced fission data of Np-237

    Energy Technology Data Exchange (ETDEWEB)

    Win, Than; Saito, Keiichiro; Baba, Mamoru; Iwasaki, Tomohiko; Ibaraki, Masanobu; Miura, Takako; Sanami, Toshiya; Nauchi, Yasushi; Hirakawa, Naohiro [Tohoku Univ., Sendai (Japan). Faculty of Engineering

    1998-03-01

    We have performed the following measurements for {sup 237}Np using the 4.5 MV Dynamitron accelerator of Tohoku University as the pulsed neutron source: (1) Prompt fission neutron spectrum for 0.62 MeV incident neutrons, and (2) Neutron-Induced fission cross-section between 10 and 100 keV. The prompt fission neutron spectrum was measured using TOF method with a heavily shielded NE213 scintillation detector. The Maxwellian temperature T{sub m} derived is 1.28 MeV, which is lower than that of 1.38 MeV in JENDL-3.2. The fission cross sections were measured between 10 - 100 keV. The results are between JENDL-3.2 and ENDF/B-VI. (author)

  17. 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.

  18. 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.

  19. Measurements of {sup 237}Np secondary neutron spectra

    Energy Technology Data Exchange (ETDEWEB)

    Kornilov, N.V.

    1997-03-01

    The activities carried out during the first year of the project are summarized. The main problems for Np spectra measurements arise from high intrinsic gamma-ray activity of the sample and admixture of the oxygen and iron nuclei. The inelastically scattered neutrons and the fission neutrons spectra for {sup 237}Np were measured by time-of-flight spectrometer of the IPPE at incident neutron energies {approx_equal}1.5 MeV, and {approx_equal}0.5 MeV. A solid tritium target and a Li-metallic target were used as neutron sources. The neutron scattering on C sample (C(n,n) standard reaction) was measured to normalize the Np data. The experimental data should be simulated by Monte Carlo method to correct the experimental data for oxygen and iron admixture as well as for multiple scattering of the neutrons in the sample. Therefore the response function of the spectrometer, and the neutron energy distribution from the source were investigated in detail. (author)

  20. Helicobacter pylori and primary gastric lymphoma. A histopathologic and immunohistochemical analysis of 237 patients.

    Science.gov (United States)

    Nakamura, S; Yao, T; Aoyagi, K; Iida, M; Fujishima, M; Tsuneyoshi, M

    1997-01-01

    Few previous articles have analyzed the relation between infection with Helicobacter pylori (H. pylori) and primary gastric lymphoma in a large number of patients. Resected and biopsied specimens from 237 patients with primary gastric lymphoma were investigated for H. pylori using hematoxylin and eosin stain, modified Giemsa stain, and immunohistochemistry. These specimens were compared with specimens from 29 patients with chronic active gastritis, 33 with peptic ulcers, and 41 with gastric carcinoma. H. pylori was detected in 145 of 237 patients (61%) with gastric lymphoma. The frequency of H. pylori positivity was higher in patients with lymphoma restricted to the mucosa and submucosa (76%) than in those with lymphoma invading beyond the submucosa (48%) (P gastritis (100%) (P gastritis and peptic ulcer. The H. pylori grading score for patients with lymphoma (0.9 +/- 1.0) was lower than for those with chronic active gastritis (1.9 +/- 0.8) (P < 0.001), peptic ulcers (2.2 +/- 1.0) (P < 0.001), or gastric carcinoma (1.2 +/- 1.1) (P < 0.05). These results suggest that H. pylori is more likely to be associated with early states of primary gastric lymphoma than with advanced states. Thus, H. pylori may disappear during the progression of primary gastric lymphoma.

  1. Measurements of the neutron capture cross sections and incineration potentials of minor-actinides in high thermal neutron fluxes: Impact on the transmutation of nuclear wastes; Mesures des sections efficaces de capture et potentiels d'incineration des actinides mineurs dans les hauts flux de neutrons: Impact sur la transmutation des dechets

    Energy Technology Data Exchange (ETDEWEB)

    Bringer, O

    2007-10-15

    This thesis comes within the framework of minor-actinide nuclear transmutation studies. First of all, we have evaluated the impact of minor actinide nuclear data uncertainties within the cases of {sup 241}Am and {sup 237}Np incineration in three different reactor spectra: EFR (fast), GT-MHR (epithermal) and HI-HWR (thermal). The nuclear parameters which give the highest uncertainties were thus highlighted. As a result of fact, we have tried to reduce data uncertainties, in the thermal energy region, for one part of them through experimental campaigns in the moderated high intensity neutron fluxes of ILL reactor (Grenoble). These measurements were focused onto the incineration and transmutation of the americium-241, the curium-244 and the californium-249 isotopes. Finally, the values of 12 different cross sections and the {sup 241}Am isomeric branching ratio were precisely measured at thermal energy point. (author)

  2. Evaluation of nuclear data of {sup 244}Pu and {sup 237}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Tsuneo; Konshin, V.A. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1995-10-01

    The evaluation of nuclear data for {sup 244}Pu and {sup 237}Pu was made in the neutron energy region from 10{sup -5} eV to 20 MeV. For the both nuclides, the total, elastic and inelastic scattering, fission, capture, (n,2n) and (n,3n) reaction cross sections were evaluated on the basis of theoretical calculation. The resonance parameters were given for {sup 244}Pu. The angular and energy distributions of secondary neutrons were also estimated for the both nuclides. The results were compiled in the ENDF-5 format and will be adopted in JENDL Actinoid File. (author).

  3. New radiochemical methods for determination of 237Np a 241Pu using extraction chromatography (Presentation)

    International Nuclear Information System (INIS)

    Strisovska, J.

    2013-01-01

    Thesis was focused on the development of a new methodology for the separation of anthropogenic transuranium radionuclides 237 Np a 241 Pu from different kinds of matrices. The analytical methods used in this study were based on extraction chromatography and were optimized according to the sample type. The proposed radiochemical procedure is a combination of two algorithms, which represent the separation of radionuclides by using extraction chromatographic sorbents TEVA resin and TRU resin supplied by Eichrom Technologies LLC. 239 Np a 237 Np were selectively captured on sorbent TEVA resin in oxidation state 4+. TRU resin was used for purification of plutonium fraction from interfering americium radionuclide. 242 Pu and 239 Np radionuclides as tracers have been used to monitor the radiochemical yields of separation. Before every radiochemical separation tracer radionuclide 239 Np was obtained by separation from the parent radionuclide 2 43 Am, which is in radioactive equilibrium to 239 Np. The average yield of chemical separation was 69,3% for 239 Np at 277 keV energy line and 65,9% at 228 keV energy line. The NPL AH-B08069 (2008) samples which consist of the mixture of alpha-radionuclides were used for the modification and optimization of separation method used for separation of Np and Pu in model samples. This method provided high radiochemical yields of 239,240 Pu (95,0 ± 3,5)% and 237 Np (87,9 ± 3,0)%.. Reliability of the method was verified by applying our modified separation procedures on reference materials IAEA-375 and IAEA-414 supplied by International Atomic Energy Agency. A good agreement between the results is obtained by this procedure and the certified values were found. Samples of contaminated soils from the area of Nuclear power plant A-1 Jaslovske Bohunice which is stored temporarily before disposal were analyzed using developed separation procedure. Specific activity of investigated radionuclides was determined in these samples. (author)

  4. Development of ionization technique for measurement of fast neutron induced fission products yields of {sup 237}Np

    Energy Technology Data Exchange (ETDEWEB)

    Goverdovski, A.A.; Khryachkov, V.A.; Ketlerov, V.V.; Mitrofanov, V.F.; Ostapenko, Yu.B.; Semenova, N.N.; Fomichev, A.N.; Rodina, L.F. [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    1997-03-01

    Twin gridded ionization chamber and corresponding software was designed for measurements of masses, kinetic energies and nuclear charges of fission fragments from fast neutron induced fission of {sup 237}Np. The ionization detector design, electronics, data acquisition and processing system and the test results are presented in this paper. (J.P.N.)

  5. NKS-Norcmass reference material for analysis of Pu-isotopes and 237Np by mass spectrometry

    International Nuclear Information System (INIS)

    Ross, P.; Nygren, U.; Appelblad, P.; Skipperud, L.; Sjoegren, A.

    2006-04-01

    The aim of the reference material in the Norcmass-project was to produce a low-level ( 239 Pu) sample of sufficient amount to allow individual laboratories to perform several tests without risk of using up the material. Although there are several reference materials available (eg IAEA) few have 239 Pu/ 240 Pu data and almost none have 237 Np/ 239 Pu-data. Those who have (eg IAEA-384) have very high concentrations and are not useful for testing analytical methods designed for low-level measurements where a large sample mass may be required. The reference material consist of the top 10cm of 2mm sieved soil pooled together from 12 different Danish locations collected during 2003. The Soil was blended and sieved through 0.6 and finally through a 0.4 mm sieve. A total amount of 17 kg soil was produced. Several aliquots of the material was subject to analysis by alpha spectrometry and ICP-MS. The material contain 239 + 240 Pu at a concentration of 0.24 ± 0.01 mBq/g and a 240 Pu/ 239 Pu atom ratio of 0.19 ± 0.006. The ratio 237 Np/ 239 Pu was determined to 0.32 ± 0.01. (au)

  6. Neutron induced fission cross sections for 232Th, 235,238U, 237Np, and 239Pu

    International Nuclear Information System (INIS)

    Lisowski, P.W.; Ullmann, J.L.; Balestrini, S.J.; Hill, N.W.; Carlson, A.D.; Wasson, O.A.

    1989-01-01

    Neutron-induced fission cross section ratios for samples of 232 Th, 235,238 U, 237 Np and 239 Pu have been measured from 1 to 400 MeV. The fission reaction rate was determined for all samples simultaneously using a fast parallel plate ionization chamber at a 20-m flight path. A well characterized annular proton recoil telescope was used to measure the neutron fluence from 3 to 30 MeV. Those data provided the shape of the 235 U(n,f) cross section relative to the hydrogen scattering cross section. That shape was then normalized to the very accurately known value for 235 U(n,f) at 14.178 MeV. From 30 to 400 MeV cross section values were determined using the neutron fluence measured with a plastic scintillator. Cross section values of 232 Th, 235,238 U, 237 Np and 239 Pu were computed from the ratio data using the authors' values for 235 U(n,f). In addition to providing new results at high neutron energies, these data highlight several areas of deficiency in the evaluated nuclear data files and provide new information for the 235 U(n,f) standard

  7. Quality control for measurement of soil samples containing 237Np and 241Am as radiotracer

    International Nuclear Information System (INIS)

    Sha Lianmao; Zhang Caihong; Song Hailong; Ren Xiaona; Han Yuhu; Zhang Aiming; Chu Taiwei

    2003-01-01

    This paper reports quality control (QC) for the measurement of soil samples containing 237 Np and 241 Am as radiotracers in migration test of transuranic nuclides. All of the QC were done independently by the QA members of analytical work. It mainly included checking 5%-10% of the total analyzed samples; preparing blank samples, blind replicate sample and spiked samples used as quality control samples to check the quality of analytical work

  8. α-decay chain and associated cluster emission from neutron deficient 237Cf nucleus

    International Nuclear Information System (INIS)

    Jain, Deepika; Sharma, Manoj K.

    2015-01-01

    We have studied the α-decay chain of 237 Cf nucleus, which has been observed in the 3n evaporation channel when the semi-magic projectile 36 S strikes on 204 Pbv nucleus. The calculations are carried out by using preformed cluster model (PCM), with choices of spherical and quadruple deformation with in cold optimum orientation approach. The calculated half-lives of α-decay chain find relatively in nice agreement with experimental data for the deformed fragmentation approach. Along with α emission, the possibility of heavier clusters is also worked out and corresponding half-lives are predicted. (author)

  9. The field migration tests of 237Np, 238Pu, 241Am and 90Sr in aerated loess, aquifer and engineering barrier materials

    International Nuclear Information System (INIS)

    Li Shushen; Wang Zhiming; Zhao Yingjie; Fan Zhiwen; Liu Chunli; An Yongfeng; Yang Yue'e; Wu Qinghua

    2003-01-01

    This paper introduces the field migration tests of 237 Np, 238 Pu, 241 Am and 90 Sr in aerated loess, aquifer and engineering barrier materials. The tests in the aerated loess and engineering barrier materials were carried out under both natural and artificial sprinkling (15 mm/d) conditions. The tests in aquifer were carried out in both assemblies packed with undisturbed aquifer media and a definite undisturbed area. The results indicate that after 3 years tests no significant migrations were seen for all nuclides in engineering barrier materials under two kinds of conditions and in aerated loess under natural conditions. For the aerated loess under artificial sprinkling conditions, 2.7 cm (center of mass) migration in the area directly below the sand tracer layer (named as area 1) and 13 cm (peak) migration in the area outside the area 1 for 90 Sr were observed; There was no migration for 237 Np, 238 Pu and 241 Am. It was discovered that the sand layer used as carrier of nuclide tracer has barrier effect on unsaturated water and an influence on nuclide migration. This has been demonstrated by the inter comparison experiment with both sand and loess as tracer carrier. In the tracer tests of undisturbed aquifer area there was no significant migration of 237 Np, 238 Pu, 241 Am and 90 Sr after 1023 days. In the assembly 8 there was no significant migration for 238 Pu and 241 Am and a small backward migration 0.95 cm for 237 Np and 4.7 cm migration (center of mass) for 90 Sr were observed. The tests also indicate that there is no significant difference of nuclide migration in ordinary and degraded cement

  10. Measurement of the fission cross-section ratio for 237Np/235U around 14 MeV neutron energies

    International Nuclear Information System (INIS)

    Desdin, L.; Szegedy, S.; Csikai, J.

    1989-01-01

    Fission cross-section ratio was determined for 237 Np/ 235 U around 14 MeV neutron energies with a back-to-back ionization chamber. Neutrons were produced by a 180 KV accelerator using T(d,n) 4 He reaction. No significant energy dependence was found in the cross section ratio

  11. Post-Irradiation Examination of 237Np Targets for 238Pu Production

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Robert Noel [ORNL; Baldwin, Charles A [ORNL; Hobbs, Randy W [ORNL; Schmidlin, Joshua E [ORNL

    2015-01-01

    Oak Ridge National Laboratory is recovering the US 238Pu production capability and the first step in the process has been to evaluate the performance of a 237Np target cermet pellet encased in an aluminum clad. The process proceeded in 3 steps; the first step was to irradiate capsules of single pellets composed of NpO2 and aluminum power to examine their shrinkage and gas release. These pellets were formed by compressing sintered NpO2 and aluminum powder in a die at high pressure followed by sintering in a vacuum furnace. Three temperatures were chosen for sintering the solution precipitated NpO2 power used for pellet fabrication. The second step was to irradiate partial targets composed of 8 pellets in a semi-prototypical arrangement at the two best performing sintering temperatures to determine which temperature gave a pellet that performed the best under the actual planned irradiation conditions. The third step was to irradiate ~50 pellets in an actual target configuration at design irradiation conditions to assess pellet shrinkage and gas release, target heat transfer, and dimensional stability. The higher sintering temperature appeared to offer the best performance after one cycle of irradiation by having the least shrinkage, thus keeping the heat transfer gap between the pellets and clad small minimizing the pellet operating temperature. The final result of the testing was a target that can meet the initial production goals, satisfy the reactor safety requirements, and can be fabricated in production quantities. The current focus of the program is to verify that the target can be remotely dissembled, the pellets dissolved, and the 238Pu recovered. Tests are being conducted to examine these concerns and to compare results to code predictions. Once the performance of the full length targets has been quantified, the pellet 237Np loading will be revisited to determine if it can be

  12. Measurement of 237Np fission rate ratio relative to 235U fission rate in cores with various thermal neutron spectrum at the Kyoto University Critical Assembly

    International Nuclear Information System (INIS)

    Unesaki, Hironobu; Shiroya, Seiji; Iwasaki, Tomohiko; Fujiwara, Daisuke; Kitada, Takanori; Kuroda, Mitsuo; Kohashi, Akio; Kato, Takeshi; Ikeuchi, Yoshitaka

    2000-01-01

    Integral measurements of 237 Np fission rate ratio relative to 235 U fission rate have been performed at Kyoto University Citrical Assembly. The fission rates have been measured using the back-to back type double fission chamber at five thermal cores with different H/ 235 U ratio so that the neutron spectra of the cores were systematically varied. The measured fission rate ratio per atom was 0.00439 to 0.0298, with a typical uncertainty of 2 to 3%. The measured data were compared with the calculated results using SRAC/TWOTRAN and MVP based on JENDL-3.2, which gave the averaged C/E values of 0.93 and 0.95, respectively. Obtained results of C/E using 237 Np cross sections from JENDL-3/2, ENDF/B-VI.5 and JEF2.2 show that the latter two gave smaller results than JENDL-3.2 by about 4%, which clearly reflects the discrepancy in the evaluated cross section among the libraries. This difference arises from both fast fission and resonance region. Although further improvement is recommended, 237 Np fission cross section in JENDL-3.2 is considered to be superior to those in the other libraries and can be adopted for use in design calculations for minor actinide transmutation system using thermal reactors with prediction precision of 237 Np fission rate with in 10%. (author)

  13. Measurement of fast neutron induced fission cross sections of 232Th, 238U, 237Np and 243Am

    International Nuclear Information System (INIS)

    Kanda, Kazutaka; Sato, Osamu; Yoshida, Kazuo; Imaruoka, Hiromitsu; Terayama, Hiromichi; Yoshida, Masashi; Hirakawa, Naohiro

    1984-01-01

    Neutron induced fission cross sections of 232 Th, 238 U, 237 Np and 243 Am relative to 235 U were measured in the energy range from 1.5 to 6.6 MeV. The present results are compared with experimental results of others and evaluated data in JENDL-2 and ENDF/B-IV. (author)

  14. Freeze drying method for preparing radiation source material

    International Nuclear Information System (INIS)

    Mosley, W.C.; Smith, P.K.

    1976-01-01

    Fabrication of a neutron source is specifically claimed. A palladium/californium solution is freeze dried to form a powder which, through conventional powder metallurgy, is shaped into a source containing the californium evenly distributed through a palladium metal matrix. (E.C.B.)

  15. Evaluation of methods for retention of radioiodine during processing of irradiated 237Np

    International Nuclear Information System (INIS)

    Thompson, G.H.; Kelley, J.A.

    1975-06-01

    Methods of removing radioiodine from 237 Np-- 238 Pu dissolver solution and process off-gas were investigated. This program is part of a continuing effort to reduce releases of radionuclides from plant operations. Experimental data show: Greater than 99.9 percent of the radioiodine in dissolver solution can be removed by precipitation, in situ, of manganese dioxide. Silver zeolite will sorb greater than 99.9 percent of radioiodine in process off-gas. Other solid sorbents and nitric acid-mercuric nitrate scrubber solutions do not remove appreciable amounts of radioiodine from process off-gas, because radioiodine is present principally as relatively unreactive organic iodine compounds. (U.S.)

  16. Depth profiling of residual activity of ^{237}U fragments as a range verification technique for ^{238}U primary ion beam

    Directory of Open Access Journals (Sweden)

    I. Strašík

    2012-07-01

    Full Text Available Experimental and simulation data concerning fragmentation of ^{238}U ion beam in aluminum, copper, and stainless-steel targets with the initial energy 500 and 950  MeV/u are collected in the paper. A range-verification technique based on depth profiling of residual activity is presented. The irradiated targets were constructed in the stacked-foil geometry and analyzed using gamma-ray spectroscopy. One of the purposes of these experiments was depth profiling of residual activity of induced nuclides and projectile fragments. Among the projectile fragments, special attention is paid to the ^{237}U isotope that has a range very close to the range of the primary ^{238}U ions. Therefore, the depth profiling of the ^{237}U isotope can be utilized for experimental verification of the ^{238}U primary-beam range, which is demonstrated and discussed in the paper. The experimental data are compared with computer simulations by FLUKA, SRIM, and ATIMA, as well as with complementary experiments.

  17. Differences in the behavior of 233Pa, 237Np and 239 Pu in bentonite contaminated by sulfate-reducing bacteria

    International Nuclear Information System (INIS)

    Kudo, A.; Fujikawa, Y.; Takigami, H.; Zheng, J.; Asano, H.; Arai, K.; Yoshikawa, H.; Ito, M.

    1998-01-01

    The behaviors of 233 Pa, 237 Np and 239 Pu in high level radioactive wastes from nuclear fuel reprocessing were investigated by a laboratory experiment. Radioactive wastes are glassified and disposed of in geological repositories encased in bentonite as an additional artificial barrier to protect the environment. There is, however, the possibility that some anaerobic bacteria, especially sulfate-reducing bacteria, may flourish within the bentonite during the long disposal period (more than a century). The effects of sulfate-reducing bacteria on the behavior of the radionuclides within bentonite were investigated using the distribution coefficient (Kd) of 233 Pa, 237 Np and 239 Pu. The Kd was obtained with a 0.22 m membrane filter separating radionuclide contents in solid and liquid phases. The anaerobic bacteria, including sulfate-reducing bacteria, used for this investigation originated from the anaerobic treatment of pulp and paper waste and operated for more than one year at Eh around -85 mV. The bentonite used for this study was produced in Japan. The active anaerobic bacteria clearly accumulates considerable amounts of 233 Pa and 239 Pu by producing high Kd values of nearly 100,000, while Kds of 233 Pa and 239 Pu for the sterilized anaerobic bacteria were less than 10,000. In other words, live anaerobic bacteria can hold considerably higher amounts of the radionuclides compared to dead bacteria. Furthermore, high Kd values were obtained for anaerobic bacteria at pH 5-9. In contrast, Kd values for the radionuclide 237 Np were not influenced by the anaerobic bacteria but were controlled by chemical environmental conditions such as like pH. Another comparison was conducted for the radionuclides for mixtures of non-sterilized bacteria with bentonite. (author)

  18. Standard practice for the determination of 237Np, 232Th, 235U and 238U in urine by inductively coupled plasma-Mass spectrometry (ICP-MS) and gamma ray spectrometry.

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This practice covers the separation and preconcentration of neptunium-237 (237Np), thorium-232 (232Th), uranium-235 (235U) and uranium-238 (238U) from urine followed by quantitation using ICP-MS. 1.2 This practice can be used to support routine bioassay programs. The minimum detectable concentrations (MDC) for this method, taking the preconcentration factor into account, are approximately 1E-2Bq for 237Np (0.38ng), 2E-6Bq for 232Th (0.50ng), 4E-5Bq for 235U (0.50ng) and 6E-6Bq for 238U (0.48ng). 1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  19. 239Np application as tracer of 237Np in liquid effluents and nuclear wastes

    International Nuclear Information System (INIS)

    Diodati, Jorge M; Sartori, F.M.

    2003-01-01

    In this paper a technique to separate and measure 237 Np using 239 Np as a tracer, is presented. After the radiochemical separation, a liquid scintillation measurement with pulse decay discrimination and a γ measurement on the same vial is performed. The method also allows an electrodeposition for an α and γ measurement. The chemical recoveries obtained by LSC and γ spectrometry in vial are similar to those obtained by α and γ spectrometry on electroplated disc. The MDA is 0.08 Bq/l by α spectrometry and 0.22 Bq/l by LSC, with 2 σconfidence interval, and 93.7 % measurement efficiency and 98.0% chemical recovery. (author)

  20. Rapid separation method for {sup 237}Np and Pu isotopes in large soil samples

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, Sherrod L., E-mail: sherrod.maxwell@srs.go [Savannah River Nuclear Solutions, LLC, Building 735-B, Aiken, SC 29808 (United States); Culligan, Brian K.; Noyes, Gary W. [Savannah River Nuclear Solutions, LLC, Building 735-B, Aiken, SC 29808 (United States)

    2011-07-15

    A new rapid method for the determination of {sup 237}Np and Pu isotopes in soil and sediment samples has been developed at the Savannah River Site Environmental Lab (Aiken, SC, USA) that can be used for large soil samples. The new soil method utilizes an acid leaching method, iron/titanium hydroxide precipitation, a lanthanum fluoride soil matrix removal step, and a rapid column separation process with TEVA Resin. The large soil matrix is removed easily and rapidly using these two simple precipitations with high chemical recoveries and effective removal of interferences. Vacuum box technology and rapid flow rates are used to reduce analytical time.

  1. Trends in radioisotope development and utilization in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Mott, W E [Energy Research and Development Administration, Washington, D.C. (USA)

    1976-06-01

    The current trends in radioisotope and radiation technology in the United States are overviewed with emphasis on the developments since the 1973 Conference. The comments focus primarily on the research and development activities receiving the most attention today from the various agencies of the Government. Among the many available radionuclides, technetium-99m has played the single most important role for making possible the developments in the field of nuclear medicine. Many other short lived medium-lived nuclides are applied in the fields of nuclear medicine, cardiac pacemaker, artificial heart, and blood irradiator. Radiation processing is now firmly established in the United States. The trends in sewage treatment, polymer-impregnated materials, bioengineering, and food irradiation are reviewed. The programs for californium-252, strontium-90, cesium-137, plutonium-238, and krypton-85 are also reviewed. The author concludes this paper with the acknowledgement that Japanese researchers have contributed to and have been closely involved in many of the programs discussed. Of particular note is the participation in the clinical phase of the californium-252 radiotherapy program. Several Japanese hospitals have been cooperating with the United States since the very beginning of the californium-252 program in determining the value of the californium-252 neutron therapy. The research being performed is unique, and will contribute greatly to the decisions on the ultimate future of californium-252 for therapeutic purposes.

  2. High resolution measurement of the 237Np(n,f) cross section from 100keV to 2MeV

    International Nuclear Information System (INIS)

    Plattard, S.; Pranal, Y.; Blons, J.

    1975-01-01

    237 Np fission is one of the reactions utilized in the threshold detector method of neutron spectrometry for the determination of fast neutron spectra in nuclear reactors. Therefore, an accurate knowledge of the energy-dependent fission cross section is essential for a precise generation of the spectral indices of this method. A high resolution measurement of the fission cross section is presented [fr

  3. Improvement of evaluated neutron nuclear data for {sup 237}Np and {sup 241}Am

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Tsuneo; Iwamoto, Osamu; Hasegawa, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-01-01

    The nuclear data of {sup 237}Np and {sup 241}Am that are particularly important among the minor actinides were investigated by comparing JENDL-3.2 with the recent evaluated data and available experimental data. As a result of the study, several defects of JENDL-3.2 data were revealed. They were improved on the basis of experimental data or recent evaluated data. For the both nuclides, main quantities revised in the present work were the resonance parameters, cross sections, angular and energy distributions of secondary neutrons, number of neutrons per fission. The data were given in the neutron energy range from 10{sup -5} eV to 20 MeV, and compiled in the ENDF-6 format. (author)

  4. Measurement of the neutron-induced fission cross section of 237Np relative to 235U from 0.02 to 30 MeV

    International Nuclear Information System (INIS)

    Behrens, J.W.; Magana, J.W.; Browne, J.C.

    1977-01-01

    The 237 Np/ 235 U fission cross section ratio has been measured from 0.02 to 30 MeV. Using the threshold method, a value of 1.294 +- 0.019 is obtained for the average cross section ratio in the interval from 1.75 to 4.00 MeV

  5. Study of the excited levels of 233Pa by the 237Np alpha decay

    International Nuclear Information System (INIS)

    Gonzalez, J.; Gaeta, R.; Vano, E.; Los Arcos, J. M.

    1978-01-01

    The excited levels in 233 P a following the 237 N p alpha decay have been studied, by performing different experiences to complete available data and supply new information. Thus, two direct alpha spectrum measurement, one alpha-gamma bidimensional coincidence experiment, three gamma-gamma and gamma-X ray coincidences and some other measurements of the gamma spectrum, direct and coincident with alpha-particles have been made. These last experiences have allowed to obviate usual radiochemical separation methods, the 233 P a radioactive descendent interferences being eliminated by means of the coincidence technic. As a result, a primary decay scheme has been elaborated, including 15 new gamma transitions and two new levels, not observed in the most recent works. (Author) 60 refs

  6. Standard Test Method for Measuring Reaction Rates by Radioactivation of Neptunium-237

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method covers procedures for measuring reaction rates by assaying a fission product (F.P.) from the fission reaction 237Np(n,f)F.P. 1.2 The reaction is useful for measuring neutrons with energies from approximately 0.7 to 6 MeV and for irradiation times up to 30 to 40 years. 1.3 Equivalent fission neutron fluence rates as defined in Practice E 261 can be determined. 1.4 Detailed procedures for other fast-neutron detectors are referenced in Practice E 261. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  7. A comparative study of the carcinogenetic effects of 241Am, 239Pu and 237Np

    International Nuclear Information System (INIS)

    Wang Yumin; Wei Zhikang; Chen Xueyi; Yao Yongheng; Liu Peibin; Xu Lin; Lun Mingyao

    1984-01-01

    In this experiment, 420 wistar rats were used to study the comparative carcinogenetic effects of 241 Am, 239 Pu and 237 Np. These nuclides were injected to animals intravenously, subcutaneously or directly into the lung (Stansen's lung puncture method) in doses of 1.0, 5.0 and 8.5 μCi/kg, respectively. As soluble nitrate, the nuclides were rapidly transfered from the site of injection into the bone and the liver. Osteosarcomas were found in some animals 8 months to one year after intoxication. Diagnosis of osteosarcoma is based on the histopatological examination and X-ray photography. In the Am-poisoned rats the incidence of osteosarcoma is about 31-74%, varied with different doses and different routes of intoxication; in Pu-poisoned rats, the incidence of osteosarcoma is about 55-66%. while in Np-poisoned rats, it is about 36-53%. Primary lung cancers were also found in those animals poisoned by means of Stansen's lung puncture method with the above three nuclides. The incidence of primary lung cancers is about 6% in Am-and Pu-poisoned rats and 13% in Np-poisoned rats. The incidence of metastasis of osteosarcoma in lung is about 25-65% for Am-poisoned rats, 45-55% for Pu-poisoned rats and 41-80% for Np-poisoned rats. The life-span of above poisoned rats was significantly shorter than that of the normal control animals. The chemical weight for 241 Am, 239 Pu and 237 Np in same unit of radioactivity (1.0 μCi) equals to 0.308 μg, 15.9 μg and 1418.7 μg, respectively. For this reason, we have to pay more attention to the chemical mass effect in carcinogenesis of the above three nuclides

  8. Sequential Injection Method for Rapid and Simultaneous Determination of 236U, 237Np, and Pu Isotopes in Seawater

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Steier, Peter

    2013-01-01

    An automated analytical method implemented in a novel dual-column tandem sequential injection (SI) system was developed for simultaneous determination of 236U, 237Np, 239Pu, and 240Pu in seawater samples. A combination of TEVA and UTEVA extraction chromatography was exploited to separate and purify...... target analytes, whereupon plutonium and neptunium were simultaneously isolated and purified on TEVA, while uranium was collected on UTEVA. The separation behavior of U, Np, and Pu on TEVA–UTEVA columns was investigated in detail in order to achieve high chemical yields and complete purification...

  9. Manganese determination om minerals by activation analysis, using the californium-252 as a neutron source; Determinacao de manganes em minerios, por analise por ativacao, usando californio-252 como fonte de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Antonio

    1976-07-01

    Neutron Activation Analysis, using a Californium-252 neutron source, has been applied for the determination of manganese in ores such as pyrolusite, rodonite (manganese silicate)' and blending used in dry-batteries The favorable nuclear properties of manganese, such as high thermal neutron cross-section for the reaction {sup 55}Mn (n.gamma){sup 56} Mn, high concentration of manganese in the matrix and short half - life of {sup 56}Mn, are an ideal combination for non-destructive analysis of manganese in ores. Samples and standards of manganese dioxide were irradiated for about 20 minutes, followed by a 4 to 15 minutes decay and counted in a single channel pulse-height discrimination using a NaI(Tl) scintillation detector. Counting time was equal to 10 minutes. The interference of nuclear reactions {sup 56}Fe(n,p){sup 56}Mn and {sup 59} Co (n, {alpha}){sup 56} were studied, as well as problems in connection with neutron shadowing during irradiation, gamma-rays attenuation during counting and influence of granulometry of samples. One sample,was also analysed by wet-chemical method (sodium bismuthate) in order to compare results. As a whole, i t was shown that the analytical method of neutron activation for manganese in ores and blending, is a method simple, rapid and with good precision and accuracy. (author)

  10. Manganese determination om minerals by activation analysis, using the californium-252 as a neutron source; Determinacao de manganes em minerios, por analise por ativacao, usando californio-252 como fonte de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Antonio

    1976-07-01

    Neutron Activation Analysis, using a Californium-252 neutron source, has been applied for the determination of manganese in ores such as pyrolusite, rodonite (manganese silicate)' and blending used in dry-batteries The favorable nuclear properties of manganese, such as high thermal neutron cross-section for the reaction {sup 55}Mn (n.gamma){sup 56} Mn, high concentration of manganese in the matrix and short half - life of {sup 56}Mn, are an ideal combination for non-destructive analysis of manganese in ores. Samples and standards of manganese dioxide were irradiated for about 20 minutes, followed by a 4 to 15 minutes decay and counted in a single channel pulse-height discrimination using a NaI(Tl) scintillation detector. Counting time was equal to 10 minutes. The interference of nuclear reactions {sup 56}Fe(n,p){sup 56}Mn and {sup 59} Co (n, {alpha}){sup 56} were studied, as well as problems in connection with neutron shadowing during irradiation, gamma-rays attenuation during counting and influence of granulometry of samples. One sample,was also analysed by wet-chemical method (sodium bismuthate) in order to compare results. As a whole, i t was shown that the analytical method of neutron activation for manganese in ores and blending, is a method simple, rapid and with good precision and accuracy. (author)

  11. Localization of the X-linked ocular albinism gene (OA1) between DXS278/DXS237 and DXS143/DXS16 by linkage analysis

    NARCIS (Netherlands)

    Bergen, A. A.; Samanns, C.; van Dorp, D. B.; Ferguson-Smith, M. A.; Gal, A.; Bleeker-Wagemakers, E. M.

    1990-01-01

    Linkage analysis was performed in six families segregating for X-linked ocular albinism of the Nettleship-Falls type using four polymorphic DNA markers from the distal Xp. Linkage was found between the disease locus (OA1) and the loci DXS237 (theta max = 0.06, Zmax = 2.82), DXS278 (theta max = 0.03,

  12. Source storage and transfer cask: Users Guide

    International Nuclear Information System (INIS)

    Eccleston, G.W.; Speir, L.G.; Garcia, D.C.

    1985-04-01

    The storage and shield cask for the dual californium source is designed to shield and transport up to 3.7 mg (2 Ci) of 252 Cf. the cask meets Department of Transportation (DOT) license requirements for Type A materials (DOT-7A). The cask is designed to transfer sources to and from the Flourinel and Fuel Storage (FAST) facility delayed-neutron interrogator. Californium sources placed in the cask must be encapsulated in the SR-CF-100 package and attached to Teleflex cables. The cask contains two source locations. Each location contains a gear box that allows a Teleflex cable to be remotely moved by a hand crank into and out of the cask. This transfer procedure permits sources to be easily removed and inserted into the delayed-neutron interrogator and reduces personnel radiation exposure during transfer. The radiation dose rate with the maximum allowable quantity of californium (3.7 mg) in the cask is 30 mR/h at the surface and less than 2 mR/h 1 m from the cask surface. This manual contains information about the cask, californium sources, describes the method to ship the cask, and how to insert and remove sources from the cask. 28 figs

  13. Radionuclides in rodents

    International Nuclear Information System (INIS)

    Taylor, G.N.

    1985-01-01

    Studies are being conducted in mice comparing the toxicity of radium-226, plutonium-239, americium-241, californium-249 and californium-252 in C57B1/Do (albino) mice and the toxicity of americium-241, plutonium-239 and radium-226 in deer mice (Peromyscus maniculatus) and grasshopper mice (Onychomys leucogaster). These experiments will ultimately enable comparison of the toxicity of the above actinide toxicity in man to be made using radium toxicity as the baseline

  14. Data Evaluation of Actinide Cross Sections: 238Pu, 237Pu, and 236Pu

    Energy Technology Data Exchange (ETDEWEB)

    Guaglioni, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jurgenson, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Descalle, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Thompson, I. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ormand, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Escher, J. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Younes, W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mattoon, C. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Beck, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Burke, J. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bailey, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-10-04

    This report documents the recent evaluation of the 236Pu, 237Pu, and 238Pu cross section sets. Nuclear data evaluation is the fundamental interface that takes measured nuclear cross section data and turns them into a continuous curve that 1) is consistent with other measurements and nuclear reaction theory/models, and 2) is required by down-stream users. All experiments that generate nuclear data need to include an evaluation step for their data to be broadly useful to the end users.

  15. Quantum-chemical consideration of extermal valent forms of actinides

    International Nuclear Information System (INIS)

    Ionova, G.V.; Pershina, V.G.; Spitsyn, V.I.

    1982-01-01

    Stability of valent forms of actinides that has not yet studied experimentally, is considered within the framework of quantum-chemical considerations. Oxidizing potentials E 0 for actinide elements are determined theoretically. A dependence of the definite valent state stability on relativistic effect is shown. A conclusion is made that oxidizing potential E 0 (4-5) for americium should be higher than E 0 (4-5) for plutonium. A relatively small oxidizing potential E 0 (4-5) for curium speaks about principle possibility of production of five-valent curium in solution, though it is less stable than the six-valent one. Oxidizing potential corresponding to transition of three-valent californium into the four-valent state should be less than the value adopted in literature. A relatively small oxidizing potential of californium E 0 (4-5) speaks about possible existence of five-valent californium in solution

  16. Design of a homogeneous subcritical nuclear reactor based on thorium with a source of californium 252; Diseno de un reactor nuclear subcritico homogeneo a base de Torio con una fuente de Californio 252

    Energy Technology Data Exchange (ETDEWEB)

    Delgado H, C. E.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico); Sajo B, L., E-mail: ce_delgado89@hotmail.com [Universidad Simon Bolivar, Laboratorio de Fisica Nuclear, Apdo. 89000, 1080A Caracas (Venezuela, Bolivarian Republic of)

    2015-10-15

    Full text: One of the energy alternatives to fossil fuels which do not produce greenhouse gases is the nuclear energy. One of the drawbacks of this alternative is the generation of radioactive wastes of long half-life and its relation to the generation of nuclear materials to produce weapons of mass destruction. An option to these drawbacks of nuclear energy is to use Thorium as part of the nuclear fuel which it becomes in U{sup 233} when capturing neutrons, that is a fissile material. In this paper Monte Carlo methods were used to design a homogeneous subcritical reactor based on thorium. As neutron reflector graphite was used. The reactor core is homogeneous and is formed of 70% light water as moderator, 12% of enriched uranium UO{sub 2}(NO{sub 3}){sub 4} and 18% of thorium Th(NO{sub 3}){sub 4} as fuel. To start the nuclear fission chain reaction an isotopic source of californium 252 was used with an intensity of 4.6 x 10{sup 7} s{sup -1}. In the design the value of the effective multiplication factor, whose value turned out k{sub eff} <1 was calculated. Also, the neutron spectra at different distances from the source and the total fluence were calculated, as well as the values of the ambient dose equivalent in the periphery of the reactor. (Author)

  17. Fission mode analysis of the reaction 237Np(n,f) - possibilities and perspectives

    International Nuclear Information System (INIS)

    Siegler, P.

    1996-01-01

    Fission fragment properties for the reaction 237 Np(n,f) have been measured at the Van de Graaff Laboratory of the IRMM. Using a double gridded ionization chamber the mass, kinetic energy and the angular distribution for both fission fragments could be determined simultaneously for an incident neutron energy range from E n =0.3 MeV upto E n =5.5 MeV. Complete datasets have been acquired for 13 different neutron energies covering sub barrier fission as well as fission in the plateau region. A detailed analysis of the fragment distributions and the respective momenta has been carried out, checking the coherence against the excitation energy of the compound nucleus. The consideration of multi-modal fission offers an improved possibility for the description of the fragment distributions backed up by theoretical calculations on the basis of the multi-model random-neck rupture model of Brosa, Grossmann and Mueller. The changes of the fission fragment properties under investigation are completely described and an interpretation of the findings is presented. (author)

  18. Review of fission product yields and delayed neutron data for the actinides NP-237, PU-242, AM-242M, AM-243, CM-243 and CM-245

    International Nuclear Information System (INIS)

    Mills, R.W.

    1990-07-01

    A review of fission product yields and delayed neutron data for Np-237, Pu-242, Am-242m, Am-243, Cm-243 and Cm-245 has been undertaken. Gaps in understanding and inconsistencies in existing data were identified and priority areas for further experimental, theoretical and evaluation investigation detailed

  19. Study of the excited levels of 233{sup P}a by the 237{sup N}p alpha decay; Estudio de los niveles excitados en el 233{sup P}a por la desintegracion alfa del 237{sup N}p

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, J; Gaeta, R; Vano, E; Los Arcos, J M

    1978-07-01

    The excited levels in 233{sup P}a following the 237{sup N}p alpha decay have been studied, by performing different experiences to complete available data and supply new information. Thus, two direct alpha spectrum measurement, one alpha-gamma bidimensional coincidence experiment, three gamma-gamma and gamma-X ray coincidences and some other measurements of the gamma spectrum, direct and coincident with alpha-particles have been made. These last experiences have allowed to obviate usual radiochemical separation methods, the 233{sup P}a radioactive descendent interferences being eliminated by means of the coincidence technic. As a result, a primary decay scheme has been elaborated, including 15 new gamma transitions and two new levels, not observed in the most recent works. (Author) 60 refs.

  20. The evaluation of the 237Np fission cross section in the 20 KeV - 20 MeV energy range

    International Nuclear Information System (INIS)

    Dushin, V.N.; Kalinin, V.A.; Shpakov, V.I.

    1997-01-01

    The results of the development of nuclear data evaluation based on the generalized least squares method is presented. The method to interpolate experimental data measured at arbitrary energy points, and their transfer to a fixed energy grid is described. The results of the 237 Np fission cross section measurements performed until 1988 were critically analyzed. A 781 x 781 covariant matrix was derived from the correlation analysis of the experimental results. The results of the evaluation, and the associated correlation matrix was obtained using the generalized least square method. (author). 34 refs, 4 figs, 2 tabs

  1. Neutron induced fission cross sections for /sup 232/Th, /sup 235,238/U, /sup 237/Np and /sup 239/Pu from 1 to 400 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Lisowski, P.W.; Ullmann, J.L.; Balestrini, S.J.; Carlson, A.D.; Wasson, O.A.; Hill, N.W.

    1988-01-01

    Neutron-induced fission cross section ratios for samples of /sup 232/Th, /sup 235,238/U, /sup 237/Np and /sup 239/Pu have been measured from 1 to 400 MeV. The fission reaction rate was determined for all samples simultaneously using a fast parallel plate ionization chamber at a 20-m flight path. A well characterized annular proton recoil telescope was used to measure the neutron fluence up to 30 MeV. These data provided the shape of the /sup 235/U(n,f) cross section relative to the hydrogen scattering cross section. That shape was then normalized to the very accurately known values were determined using the neutron fluence measured with a second proton recoil telescope. Cross section values for /sup 232/Th, /sup 238/U, /sup 237/Np, and /sup 239/Pu were computed from the ratio data using our values for /sup 235/U(n,f). In addition to providing new results at high neutron energies, these data resolve long standing discrepancies among different data sets. 1 ref., 1 fig.

  2. Measurement and analysis of reactivity worth of 237Np sample in cores of TCA and FCA

    International Nuclear Information System (INIS)

    Sakurai, Takeshi; Mori, Takamasa; Okajima, Shigeaki; Tani, Kazuhiro; Suzaki, Takenori; Saito, Masaki

    2009-01-01

    The reactivity worth of 22.87 grams of 237 Np oxide sample was measured and analyzed in seven uranium cores in the Tank-Type Critical Assembly (TCA) and two uranium cores in the Fast Critical Assembly (FCA) at the Japan Atomic Energy Agency. The TCA cores provided a systematic variation in the neutron spectrum between the thermal and resonance energy regions. The FCA cores, XXI and XXV, provided a hard neutron spectrum of the fast reactor and a soft one of the resonance energy region, respectively. Analyses were carried out using the JENDL-3.3 nuclear data library with a Monte Carlo method for the TCA cores and a deterministic method for the FCA cores. The ratios of calculated to experimental (C/E) reactivity worth were between 0.97 and 0.91, and showed no apparent dependence on the neutron spectrum. (author)

  3. Adsorption-desorption characteristics of plutonium and americium with sediment particles in the estuarine environment: studies using plutonium-237 and americium-241

    International Nuclear Information System (INIS)

    Murray, C.N.; Fukai, R.

    1975-01-01

    The particle formation of plutonium and americium, their adsorption onto fresh water sediments and the desorption from the sediments in sea water were studied in the Laboratory under simulated river-estuary conditions, using γ-emitting plutonium-237 and americium-241. The results of the experiments show that the particle formation of plutonium depends on its valence states, on pH and on the salinity of the medium. For river water at pH4, some 25%, 20% and 30% of the added 237 Pu was in particulate form, larger than 0.45 μm, for Pu (III), Pu (IV) and Pu (VI), respectively, while 65%, 90% and 50% of the respective valence states was associated with particles at pH 8. In sea water the general pattern remains similar, although Pu (VI) is more soluble in sea water owing to higher ligand concentrations for carbonate and bicarbonate complexes. The pH-dependency of particle formation of Am (III) is more steep than that of plutonium and seems to be influenced by colloidal substances occurring in the experimental media. The adsorption-desorption characteristics of plutonium and americium with the sediment in river water as well as sea water reflect the characteristics of their particle formation, being dependent upon such properties as valence states, the pH and salinity of the medium. A sewage effluent added to the media has small but measurable effects on the adsorption-desorption processes of plutonium. (author)

  4. The z = 1.6748 C I Absorber Toward the QSO PKS 1756+237

    Science.gov (United States)

    Roth, Katherine C.; Bauer, James M.; Jim, Kevin T. C.

    We have detected C I ground-state absorption at zabs = 1.6748 toward the QSO PKS 1756+237 (zem = 1.725), making this only the fourth known C I QSO absorber. The absence of excited-state fine-structure C I lines is compatible with the redshifted Cosmic Microwave Background Radiation at an expected temperature of TCMBR (1+z) = 7.291 K (Mather et al. 1994, ApJ, 354, L37). We find a 2 σ upper-limit on the C I excitation temperature of Tex <= 7.73(+0.53, -0.46) K (Roth & Bauer 1999, ApJ, submitted). Our Keck HIRES spectra (8.3 km s-1 FWHM) obtained in May 1997 also reveal the existence of Ni II and Fe II lines with a sub-solar Ni/Fe abundance ratio, presumably indicative of dust. We have obtained deep, high resolution (0.3'' FWHM) images in H+K' with the UH 2.2m Tip-Tilt system of the QSO field in order to identify the system responsible for the zabs = 1.6748 absorption. We detect two faint candidate systems within 1.5'' and 3'' (≅ 15 and 30 kpc, Hcirc = 65) of the QSO.

  5. Early retention of 237Pu + 239Pu in mature beagles

    International Nuclear Information System (INIS)

    Lloyd, R.D.; McFarland, S.S.; Atherton, D.R.; Bruenger, F.W.; Taylor, G.N.; Mays, C.W.

    1978-01-01

    Five mature beagles, ranging in age from 57 to 84 months, were injected intravenously with about 0.05-0.1 μCi/kg of 239 Pu(IV) citrate to which tracer amounts of the photon-emitter 237 Pu had been added. Plutonium retention in liver and in non-liver tissue (mainly skeleton) was measured periodically in the living dogs for nearly 4 months after injection by a combination of total-body and partial-body counting. All excreta were collected during the first 21 days and analysed for their Pu content. One dog was sacrificed at 14 days and another at 118 days for distribution studies. About 17% (14-20%) of the injected Pu was excreted in the urine and feces in the first 3 weeks, about the same as that excreted in a corresponding time by beagles injected as young adults (14%), but substantially more than beagles injected as juveniles (11%). In contrasts to juvenile beagles injected at 3 months of age, in which early retention was about 12% in liver and 68% in the skeleton, mature beagles retained about 30% in liver and 50% in the skeleton. Retention in young adult beagles injected at 17 months of age was similar to that of mature dogs. Relative distribution of skeletal plutonium among various bones was similar in the mature animals to that seen previously in young adults, but quite different from that of juveniles. A notable exception was the humerus for which there was no significant difference (P>0.2) in the % of retained skeletal Pu represented by the humerus among the juvenile, young adult and mature dogs. (author)

  6. Pigmented villonodular synovitis: a retrospective multicenter study of 237 cases.

    Directory of Open Access Journals (Sweden)

    Guo-ping Xie

    Full Text Available To review clinical characteristics of pigmented villonodular synovitis (PVNS in China.Electronic medical records (EMR of four Chinese institutes were queried for patients with histologically proven PVNS between January 2005 and February 2014. Their data were collected including gender, age at diagnosis, clinical presentation, affected site, symptom duration, comorbidities, treatment strategy, recurrence and routine laboratories.A total of 237 patients with biopsy-proven PVNS were investigated. The gender ratio was 1.35 for a female predominance (101 males and 136 females. The average age was 36 years (range, 2 to 83 years. The median delay from initial clinical symptom to diagnosis was 18 months. Main affected areas were the knee (73.84% and the hip (18.14%. Forty patients had a clear history of joint trauma. Six patients were concurrently diagnosed with PVNS and avascular necrosis (AVN. Five patients suffered from PVNS following implantation of orthopaedic devices including artificial prosthesis, plate and wire. One hundred and twenty-nine patients underwent arthroscopic synovectomy and 108 open synovectomy. Altogether 48 patients (26 males and 22 females had recurrence of disease. The relapse rate was 24% (knee and 6.98% (hip, 20.93% (open surgery and 19.44% (arthroscopy, respectively. Erythrocyte sedimentation rate (ESR and C-reactive protein (CRP rate were elevated in 45.83% and 38.41% of the patients respectively.To our knowledge, this study is the largest sample size of PVNS patients reported as well as the largest sample of PVNS with concurrent AVN reported to date. Our outcomes suggest that PVNS shows a female predominance, occurs mostly between 20-40 years and favors the knee and hip. Recurrence is frequent, particularly in the knee. Serum ESR and CRP may be elevated in some patients. Additionally, the present study supports the theory of an association between PVNS and orthopedic surgery, which is not limited to joint replacement.

  7. Poor adherence to medication as assessed by the Morisky Medication Adherence Scale-8 and low satisfaction with treatment in 237 psoriasis patients.

    Science.gov (United States)

    Saeki, Hidehisa; Imafuku, Shinichi; Abe, Masatoshi; Shintani, Yoichi; Onozuka, Daisuke; Hagihara, Akihito; Katoh, Norito; Murota, Hiroyuki; Takeuchi, Satoshi; Sugaya, Makoto; Tanioka, Miki; Kaneko, Sakae; Masuda, Koji; Hiragun, Takaaki; Inomata, Naoko; Kitami, Yuki; Tsunemi, Yuichiro; Abe, Shinya; Kobayashi, Miwa; Morisky, Donald E; Furue, Masutaka

    2015-04-01

    Previously we assessed the medication adherence for oral and topical remedies by a translated Japanese version of the Morisky Medication Adherence Scale-8 (MMAS-8) together with socioeconomic backgrounds in 3096 Japanese dermatological patients, and found the medication adherence, especially to topical drugs, was poor in these patients. In order to elucidate the disease-specific sociomedical factors, we further sub-analyzed the medication adherence in 237 psoriasis patients and compared it with that in other dermatological diseases such as atopic dermatitis, urticaria or tinea. This study was conducted among patients registered in monitoring system and 3096 eligible patients were enrolled. Our web-based questionnaire included the following items such as age, sex, annual income, main health-care institution, experience of effectiveness by oral or topical medication, overall satisfaction with treatment, and MMAS-8 for oral or topical medication. Mean adherence score by MMAS-8 was 5.2 for oral and 4.3 for topical medication. More patients with psoriasis used a university hospital and fewer used a private clinic compared with those with the other skin disease patients. Experience of drug effectiveness by oral medication and overall satisfaction with treatment was lower in psoriasis patients than in other patients. In oral medication, significantly better adherence was observed in those of higher age and with higher annual income. The adherence to medication, especially to topical drugs, was poor in 237 psoriasis patients. We speculated that some severe psoriasis patients were not sufficiently treated systemically and were resistant to topical therapy, leading to poor adherence. © 2015 Japanese Dermatological Association.

  8. A correlation between isomer shifts of 237Np Moessbauer spectra and coordination numbers of Np atoms in neptunyl(V) compounds

    International Nuclear Information System (INIS)

    Saeki, M.; Nakada, M.; Nakamoto, T.; Yamashita, T.; Masaki, N.M.; Krot, N.N.

    1999-01-01

    Five neptunyl(V) compounds were synthesized and studied by 237 Np Moessbauer spectroscopy. The isomer shifts (δ) of the Moessbauer spectra ranged from -18.6 to -19.1 mm/s for the compounds with Np atoms surrounded by 7 oxygen atoms (coordination number (CN) 7). On the other hand, the larger value of δ was obtained for the compound with CN 8. From the comparison of the present results with those reported on neptunyl(V) and (VI) compounds, it is concluded that there is a correlation between the δ and the CN for neptunyl(V) compounds, and the distribution of δ is narrower for neptunyl(V) compounds than that of neptunyl(VI) compounds. (author)

  9. Measurement of the Neutron Capture Cross Sections of $^{233}$U, $^{237}$Np, $^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm with a Total Absorption Calorimeter at n_TOF

    CERN Multimedia

    Beer, H; Wiescher, M; Cox, J; Rapp, W; Embid, M; Dababneh, S

    2002-01-01

    Accurate and reliable neutron capture cross section data for actinides are necessary for the poper design, safety regulation and precise performance assessment of transmutation devices such as Fast Critical Reactors or Accelerator Driven Systems (ADS). The goal of this proposal is the measurement of the neutron capture cross sections of $^{233}$U, $^{237}$Np, $^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm at n_TOF with an accuracy of 5~\\%. $^{233}$U plays an essential role in the Th fuel cycle, which has been proposed as a safer and cleaner alternative to the U fuel cycle. The capture cross sections of $^{237}$Np,$^{240,242}$Pu, $^{241,243}$Am and $^{245}$Cm play a key role in the design and optimization of a strategy for the Nuclear Waste Transmutation. A high accuracy can be achieved at n_TOF in such measurements due to a combination of features unique in the world: high instantaneous neutron fluence and excellent energy resolution of the facility, innovative Data Acquisition System based on flash ADCs and t...

  10. Montecarlo calculation of the isomeric cross sections ratio for the reaction 237Np(n,2n)236Np

    International Nuclear Information System (INIS)

    Cleri, F.

    1988-01-01

    A Montecarlo calculation of the isomeric cross section ratio for the (n,2n) reaction on 237 Np has been carried out based on the Hauser-Feshbach formulation. A standard energy-dependent optical model potential was used, with zero deformation parameters and no spin-orbit coupling. Investigation was made about the role of the energy cut-off value, of the higher multipole (E2) transition, of the gamma-ray versus second neutron emission, of the value of the spin cutt-off parameter. The results give the correct qualitative energy dependence of the branching ratio, with the assumption that the 1 - level is the ground state. The spin cut-off value obtained indicates a less pronounced deviation of the nuclear moment of inertia from the rigid-body value, with respect to older evaluations for high-mass nuclei. (author)

  11. 16 CFR 23.7 - Misuse of the words “platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium,” and “osmium.”

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Misuse of the words âplatinum,â âiridium,â... § 23.7 Misuse of the words “platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium,” and “osmium.” (a) It is unfair or deceptive to use the words “platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium...

  12. Fragment properties in the fission of 237Np with fast neutrons - an experimental investigation of fission dynamics

    International Nuclear Information System (INIS)

    Naqvi, A.A.

    1980-03-01

    Fission fragment properties such as mass distribution, kinetic energy distribution or number of prompt emitted neutrons as a function of fragment mass can be used to characterize the scission point configuration. The present experiment allows for the first time to investigate these quantities for neutron induced fission in the MeV range. In this way the influence of excitation energy of the saddle point deformation of the fissioning system ( 237 Np + n) can be studied. Neutrons with energies of 0.8 and 5.5 MeV were produced by the Karlsruhe pulsed 3MV Van de Graaff accelerator. Kinetic energies and velocities of correlated fragments were determined by solid state detectors using the time-of-flight technique. The experimentally determined distributions of fragment properties were compared to a recent model suggested by Wilkins et al. which assumes only relatively weak coupling between internal and collective degrees of freedom. At least qualitative agreement is found for most of the results. (orig.) [de

  13. Ultra-trace determination of neptunium-237 and plutonium isotopes in urine samples by compact accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Dai, X.; Christl, M.; Kramer-Tremblay, S., E-mail: sheila.kramer-tremblay@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Synal, H-A. [ETH Zurich, Lab. of Ion Beam Physics, Zurich (Switzerland)

    2015-12-15

    Ultra-trace analysis of actinides, such as Pu isotopes and {sup 237}Np, in bioassay samples is often needed for radiation protection programs at nuclear facilities. Accelerator mass spectrometry (AMS), particularly the compact ETH Zurich system “Tandy”, has evolved over the years as one of the most sensitive, selective, and robust techniques for actinide analysis. Employment of the AMS technique can reduce the demands on sample preparation chemistry and increase sample analysis throughput, due to very low instrumental detection limit, high rejection of interferences, and low susceptibility to adverse sample matrices. Initial research and development tests were performed to explore and demonstrate the analytical capability of AMS for Pu and Np urine bioassay. In this study, urine samples spiked with femtogram levels of Np and Pu isotopes were prepared and measured using compact ETH AMS system and the results showed excellent analytical capability for measuring Np and Pu isotopes at femtogram/litre levels in urine. (author)

  14. Evaluation and improvement of cross section accuracy for most important dosimetry reactions 27Al(n,p), 56Fe(n,p) and 237Np(n,f) including covariance data

    International Nuclear Information System (INIS)

    Zolotarev, K.I.

    2004-02-01

    New evaluations of cross sections and their uncertainties for dosimetry reactions 27 Al(n,p) , 56 Fe(n,p) and 237 Np(n,f) have been carried out in the frame work of IAEA Research Contract No. 11372/RB. Data files prepared for this reactions in the ENDF-6 format may be consider as candidates for the new International Reactor Dosimetry File: IRDF-2002. (author)

  15. Transmutation of 129I and 237Np using spallation neutrons produced by 1.5, 3.7 and 7.4 GeV protons

    International Nuclear Information System (INIS)

    Wan, J.-S.; Schmidt, T.Th.; Langrock, E.-J.; Vater, P.; Brandt, R.; Adam, J.; Bradnova, V.; Bamblevski, V.P.; Gelovani, L.; Gridnev, T.D.; Kalinnikov, V.G.; Krivopustov, M.I.; Kulakov, B.A.; Sosnin, A.N.; Perelygin, V.P.; Pronskikh, V.S.; Stegailov, V.I.; Tsoupko-Sitnikov, V.M.; Modolo, G.; Odoj, R.; Phlippen, P.-W.; Zamani-Valassiadou, M.; Adloff, J.C.; Debeauvais, M.; Hashemi-Nezhad, S.R.; Guo, S.-L.; Li, L.; Wang, Y.-L.; Dwivedi, K.K.; Zhuk, I.V.; Boulyga, S.F.; Lomonossova, E.M.; Kievitskaja, A.F.; Rakhno, I.L.; Chigrinov, S.E.; Wilson, W.B.

    2001-01-01

    Small samples of 129 I and 237 Np, two long-lived radwaste nuclides, were exposed to spallation neutron fluences from relatively small metal targets of lead and uranium, that were surrounded with a 6 cm thick paraffin moderator, and irradiated with 1.5, 3.7 and 7.4 GeV protons. The (n,γ) transmutation rates were determined for these nuclides. Conventional radiochemical La- and U-sensors and a variety of solid-state nuclear track detectors were irradiated simultaneously with secondary neutrons. Compared with results from calculations with well-known cascade codes (LAHET from Los Alamos and DCM/CEM from Dubna), the observed secondary neutron fluences are larger

  16. Transmutation of 129I and 237Np using spallation neutrons produced by 1.5, 3.7 and 7.4 GeV protons

    Science.gov (United States)

    Wan, J.-S.; Schmidt, Th.; Langrock, E.-J.; Vater, P.; Brandt, R.; Adam, J.; Bradnova, V.; Bamblevski, V. P.; Gelovani, L.; Gridnev, T. D.; Kalinnikov, V. G.; Krivopustov, M. I.; Kulakov, B. A.; Sosnin, A. N.; Perelygin, V. P.; Pronskikh, V. S.; Stegailov, V. I.; Tsoupko-Sitnikov, V. M.; Modolo, G.; Odoj, R.; Phlippen, P.-W.; Zamani-Valassiadou, M.; Adloff, J. C.; Debeauvais, M.; Hashemi-Nezhad, S. R.; Guo, S.-L.; Li, L.; Wang, Y.-L.; Dwivedi, K. K.; Zhuk, I. V.; Boulyga, S. F.; Lomonossova, E. M.; Kievitskaja, A. F.; Rakhno, I. L.; Chigrinov, S. E.; Wilson, W. B.

    2001-05-01

    Small samples of 129I and 237Np, two long-lived radwaste nuclides, were exposed to spallation neutron fluences from relatively small metal targets of lead and uranium, that were surrounded with a 6 cm thick paraffin moderator, and irradiated with 1.5, 3.7 and 7.4 GeV protons. The (n,γ) transmutation rates were determined for these nuclides. Conventional radiochemical La- and U-sensors and a variety of solid-state nuclear track detectors were irradiated simultaneously with secondary neutrons. Compared with results from calculations with well-known cascade codes (LAHET from Los Alamos and DCM/CEM from Dubna), the observed secondary neutron fluences are larger.

  17. Evaluation and improvement of cross section accuracy for most important dosimetry reactions 27Al(n,p), 56Fe(n,p) and 237Np(n,f) including covariance data

    Energy Technology Data Exchange (ETDEWEB)

    Zolotarev, K I [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    2004-02-01

    New evaluations of cross sections and their uncertainties for dosimetry reactions {sup 27}Al(n,p) , {sup 56}Fe(n,p) and {sup 237}Np(n,f) have been carried out in the frame work of IAEA Research Contract No. 11372/RB. Data files prepared for this reactions in the ENDF-6 format may be consider as candidates for the new International Reactor Dosimetry File: IRDF-2002. (author)

  18. Precise 238U(n,2n)237U reaction cross-section measurements using the activation facility at TUNL

    Science.gov (United States)

    Krishichayan, Fnu; Bhike, M.; Tornow, W.

    2014-09-01

    Accurate neutron-induced 238U(n,2n)237U reaction data are required for many practical applications, especially in the field of nuclear energy, including advanced heavy water reactors, where 238U is used as the breeding material to regenerate the fissile material 239Pu. Precise (n,2n) cross-section measurements of 238U are underway at TUNL with mono-energetic neutrons in the 8.0 to 14.0 MeV energy range in steps of 0.25 MeV using the activation technique. After activation of the 0.5 inch diameter and 442 mg 238U foil, the activity of the 208 keV characteristic γ-line is tracked for 6 weeks with a high efficient HPGe clover detector to determine the initial activity needed for the cross-section determination. Results of the cross-section measurements, determined relative to 27Al and 197Au neutron activation monitor foils, and the comparison with theoretical models will be presented during the meeting.

  19. Transmutation of 129I and 237Np using spallation neutrons produced by 1.5, 3.7 and 7.4 GeV protons

    International Nuclear Information System (INIS)

    Ochs, M.; Schmidt, Th.; Wan, J.-S.

    1999-01-01

    Small samples of approximately 1 g of 129 I and 237 Np, two long-lived radioactive waste nuclides, were exposed to spallation neutron fluences from relatively small metal targets of lead or uranium, surrounded with a paraffin moderator 6 cm thick irradiated with 1.5, 3.7 and 7.4 GeV protons. The (n, γ) transmutation rates have been determined for the two radioactive waste nuclides. Conventional radiochemical La and U sensors and a variety of solid-state nuclear track detectors were irradiated simultaneously with secondary neutrons. The observed secondary neutron fluences appear to be systematically larger, as compared to the calculations with the well-known cascade codes (LAHET from Los Alamos and DCM-CEM from Dubna)

  20. The bioavailability of the transuranic elements 237Pu and 241Am for the pond snail, Lymnaea stagnalis L., and their behaviour in selected natural surface waters

    International Nuclear Information System (INIS)

    Thiels, G.M.

    1983-01-01

    An attempt was made to characterise the bioavailability of 237 Pu and 241 Am for the pond snail Lymnaea stagnalis L. in selected surface waters. The uptake, distribution and retention patterns were studied through the contamination route water-snail. The effects of a number of parameters, such as seasonal variation, water type (pH, conductivity, ionic composition) and presence of food, on the bioavailability of the transuranics were evaluated. Finally, an assessment was made concerning the chemical speciation of plutonium and americium in the selected freshwaters

  1. Numerical methods to analyze alpha spectra and application to the study of neptunium 237 and neptunium 236

    International Nuclear Information System (INIS)

    Garcia-Torano, E.

    1990-01-01

    A set of numerical methods to analize alpha spectra measured with semiconductor detectors are presented. The methods can be divided in two groups, the first being based in the X 2 minimization ands the second in the use of the Fourier Transform. The methods based in the minimization of X 2 can, in turn, be divided according to the model used to fit the spectra. Some of them use a monoenergetic line for the intercomparison with the other peaks in the same spectrum. The others take into account the analytical function developed to represent an alpha line. Both allow the determination of positions and areas of the components, as well as the uncertainties of the results. The Fast Fourier Transform is applied to the second group of methods, which include the smoothing of experimental data, and the deconvolution of spectra. Examples are given of the application of these methods to real spectra. The alpha spectra of 237 Np and 236 Np are studied by using some of the methods described in this work. (Author)

  2. The quadrupole moment and strong interaction parameters from muonic and pionic X-ray studies of 237Np

    International Nuclear Information System (INIS)

    Laat, C.T.A.M. de; Taal, A.; Duinker, W.; Konijn, J.; Petitjean, C.; Reist, H.W.; Mueller, W.; Commission of the European Communities, Geel

    1987-01-01

    The X-ray spectrum of muonic and pionic 237 Np has been investigated with muons and pions stopped in a NpO 2 target. The nuclear spectroscopic quadrupole moment was determined to be Q=3.886±0.006 b from the splittings of the muonic 5g→4f hyperfine complexes. The B(E2)↓-values for the first and second excited states were evaluated as 3.17±0.08 and 2.77±0.10 e 2 b 2 , respectively. A comparison between the muonic and pionic 5g→4f hyperfine complexes yields the strong interaction parameter for the pionic 4f state. For the first time a change of sign as function of Z for the strong interaction quadrupole shift ε 2 (4f) has been observed. The standard optical model predictions agree reasonably well with the measured strong interaction monopole shift, ε 0 (4f), and width, Γ 0 (4f), while they disagree with the experimental value for ε 2 . A stronger s-wave repulsion in the optical potential could explain this effect. (orig.)

  3. First simultaneous measurement of fission and gamma probabilities of 237U and 239Np via surrogate reactions

    Directory of Open Access Journals (Sweden)

    Marini P.

    2016-01-01

    Full Text Available Fission and gamma decay probabilities of 237U and 239Np have been measured, for the first time simultaneously in dedicated experiments, via the surrogate reactions 238U(3He, 4He and 238U(3He,d, respectively. While a good agreement between our data and neutron-induced data is found for fission probabilities, gamma decay probabilities are several times higher than the corresponding neutron-induced data for each studied nucleus. We study the role of the different spin distributions populated in the surrogate and neutron-induced reactions. The compound nucleus spin distribution populated in the surrogate reaction is extracted from the measured gamma-decay probabilities, and used as input parameter in the statistical model to predict fission probabilities to be compared to our data. A strong disagreement between our data and the prediction is obtained. Preliminary results from an additional dedicated experiment confirm the observed discrepancies, indicating the need of a better understanding of the formation and decay processes of the compound nucleus.

  4. Absolute and relative cross section measurements of 237Np(n,f and 238U(n,f at the National Physical Laboratory

    Directory of Open Access Journals (Sweden)

    Salvador-Castiñeira Paula

    2017-01-01

    Full Text Available Cross section measurements in the fast energy region are being demanded as one of the key ingredients for modelling Generation-IV nuclear power plants. However, in facilities where there are no time-of-flight possibilities or it is not convenient to use them, using the 235U(n,f cross section as a benchmark would require a careful knowledge of the room scatter in the experimental area. In this paper we present measurements of two threshold reactions, 238U(n,f and 237Np(n,f, that could become a standard between their fission threshold and 2.5 MeV, if the discrepancies shown in the evaluations and in some experimental data can be solved. The preliminary results are in agreement with the present ENDF/B-VII.1 evaluation.

  5. Transmutation of {sup 129}I and {sup 237}Np using spallation neutrons produced by 1.5, 3.7 and 7.4 GeV protons

    Energy Technology Data Exchange (ETDEWEB)

    Wan, J.-S.; Schmidt, T.Th.; Langrock, E.-J.; Vater, P.; Brandt, R. E-mail: brandtr@mailer.uni-marburg.de; Adam, J.; Bradnova, V.; Bamblevski, V.P.; Gelovani, L.; Gridnev, T.D.; Kalinnikov, V.G.; Krivopustov, M.I.; Kulakov, B.A.; Sosnin, A.N.; Perelygin, V.P.; Pronskikh, V.S.; Stegailov, V.I.; Tsoupko-Sitnikov, V.M.; Modolo, G.; Odoj, R.; Phlippen, P.-W.; Zamani-Valassiadou, M.; Adloff, J.C.; Debeauvais, M.; Hashemi-Nezhad, S.R.; Guo, S.-L.; Li, L.; Wang, Y.-L.; Dwivedi, K.K.; Zhuk, I.V.; Boulyga, S.F.; Lomonossova, E.M.; Kievitskaja, A.F.; Rakhno, I.L.; Chigrinov, S.E.; Wilson, W.B

    2001-05-11

    Small samples of {sup 129}I and {sup 237}Np, two long-lived radwaste nuclides, were exposed to spallation neutron fluences from relatively small metal targets of lead and uranium, that were surrounded with a 6 cm thick paraffin moderator, and irradiated with 1.5, 3.7 and 7.4 GeV protons. The (n,{gamma}) transmutation rates were determined for these nuclides. Conventional radiochemical La- and U-sensors and a variety of solid-state nuclear track detectors were irradiated simultaneously with secondary neutrons. Compared with results from calculations with well-known cascade codes (LAHET from Los Alamos and DCM/CEM from Dubna), the observed secondary neutron fluences are larger.

  6. Criticality Data for Spherical 235U, 239Pu, and 237Np Systems Reflector-Moderated by Low Capturing-Moderator Materials

    International Nuclear Information System (INIS)

    Loaiza, David J.; Stratton, William

    2004-01-01

    The critical dimensions of spherical systems moderated and reflected by low-capturing materials such as D 2 O, BeO, Be, and C were investigated. A parametric study of the critical mass of enriched uranium, plutonium, and neptunium is examined and tabulated. The results obtained expand on the understanding of reflector-moderated critical systems, and they show regions of unstable criticality for 235 U and 239 Pu reflected cores at intermediate densities. This instability is illustrated by calculations of the positive reactivity coefficient of volume expansion. The coefficient is positive, not negative, in the intermediate density region for 235 U and 239 Pu systems. For 237 Np cores reflected by the same moderator, the effect is negligible. The critical dimensions were calculated with the DANTSYS codes using the Hansen-Roach cross-section libraries. This study is both a summary of mostly unpublished calculations and new calculations. Experimental data for these configurations are extremely limited. These are examined in the text when applicable

  7. Measurement of neutron-induced fission cross-sections of Th232, U238, U233 and Np237 relative to U235 from 1 MeV to 200 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Shcherbakov, O.A.; Laptev, A.B.; Petrov, G.A. [Petersburg Nuclear Physics Inst., Gatchina, Leningrad district (Russian Federation); Fomichev, A.V.; Donets, A.Y.; Osetrov, O.I.

    1998-11-01

    The measurements of neutron-induced cross-section ratios for Th232, U238, U233 and Np237 relative to U235 have been carried out in the energy range from 1 MeV up to 200 MeV using the neutron time-of-flight spectrometer GNEIS based on 1 GeV proton synchrocyclotron. Below 20 MeV, the results of present measurements are roughly in agreement with evaluated data though there are some discrepances to be resolved. (author)

  8. Definitive Brachytherapy for Kaposi's Sarcoma

    International Nuclear Information System (INIS)

    Williams, A.; Ezzell, G.; Zalupski, M.; Fontanesi, J.

    1996-01-01

    Purpose: To assess the efficacy and possible complications in patients diagnosed with Kaposi's sarcoma and treated with definitive brachytherapy. Methods and Materials: Between January, 1995 and December, 1995, four patients with Kaposi's sarcoma (KS) were treated with brachytherapy. Three patients, all with positive HIV status were treated using Iridium 192 (Ir-192) sources via a high-dose rate remote afterloader. One patient with endemic KS was treated using the application of catheters loaded with Californium 252. Eight sites were treated and included scalp, feet, nose, penis, hand, neck, and back. Dose rate for Ir-192 was 330cGy/fx to a total dose of 990cGy. The Californium was delivered as 100nGy/b.i.d. to a total dose of 900nGy. Follow-up as ranged from 2-6 months. Results: All four patients remain alive. Seven of eight sites have had complete clinical response and each patient has reported durable pain relief that has not subsided through last follow-up of 1/96. Two of eight sites, both treated with surface mold technique with Californium 252 developed moist desquamation. The remaining six sites did not demonstrate significant toxicity. Conclusion: Brachytherapy can offer Kaposi's sarcoma patients results that are equivalent to external beam radiation therapy, with minimal complications, a shorter treatment time and potential cost effectiveness

  9. Californium Recovery from Palladium Wire

    Energy Technology Data Exchange (ETDEWEB)

    Burns, Jon D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-08-01

    The recovery of 252Cf from palladium-252Cf cermet wires was investigated to determine the feasibility of implementing it into the cermet wire production operation at Oak Ridge National Laboratory’s Radiochemical Engineering Development Center. The dissolution of Pd wire in 8 M HNO3 and trace amounts of HCl was studied at both ambient and elevated temperatures. These studies showed that it took days to dissolve the wire at ambient temperature and only 2 hours at 60°C. Adjusting the ratio of the volume of solvent to the mass of the wire segment showed little change in the kinetics of dissolution, which ranged from 0.176 mL/mg down to 0.019 mL/mg. A successful chromatographic separation of 153Gd, a surrogate for 252Cf, from Pd was demonstrated using AG 50x8 cation exchange resin with a bed volume of 0.5 mL and an internal diameter of 0.8 cm.

  10. Californium-252 Program Equipment Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Chattin, Fred Rhea [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wilson, Kenton [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ezold, Julie G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-12-01

    To successfully continue the 252Cf production and meet the needs of the customers, a comprehensive evaluation of the Building 7920 processing equipment was requested to identify equipment critical to the operational continuity of the program.

  11. Accurate 238U(n , 2 n )237U reaction cross-section measurements from 6.5 to 14.8 MeV

    Science.gov (United States)

    Krishichayan, Bhike, M.; Tornow, W.; Tonchev, A. P.; Kawano, T.

    2017-10-01

    The cross section for the 238U(n ,2 n )237U reaction has been measured in the incident neutron energy range from 6.5 to 14.8 MeV in small energy steps using an activation technique. Monoenergetic neutron beams were produced via the 2H(d ,n )3He and 3H(d ,n )4He reactions. 238U targets were activated along with Au and Al monitor foils to determine the incident neutron flux. The activity of the reaction products was measured in TUNL's low-background counting facility using high-resolution γ -ray spectroscopy. The results are compared with previous measurements and latest data evaluations. Statistical-model calculations, based on the Hauser-Feshbach formalism, have been carried out using the CoH3 code and are compared with the experimental results. The present self-consistent and high-quality data are important for stockpile stewardship and nuclear forensic purposes as well as for the design and operation of fast reactors.

  12. Neutron induced fission cross section ratios for 232Th, 235,238U, 237Np and 239Pu from 1 to 400 MeV

    International Nuclear Information System (INIS)

    Lisowski, P.W.; Ullmann, J.L.; Balestrini, S.J.; Carlson, A.D.; Wasson, O.A.; Hill, N.W.

    1988-01-01

    Time-of-flight measurements of neutron induced fission cross section ratios for 232 Th, 235,238 U, 237 Np, and 239 Pu, were performed using the WNR high intensity spallation neutron source located at Los Alamos National Laboratory. A multiple-plate gas ionization chamber located at a 20-m flight path was used to simultaneously measure the fission rate for all samples over the energy range from 1 to 400 MeV. Because the measurements were made with nearly identical neutron fluxes, we were able to cancel many systematic uncertainties present in previous measurements. This allows us to resolve discrepancies among different data sets. In addition, these are the first neutron-induced fission cross section values for most of the nuclei at energies above 30 MeV. (author)

  13. Evaluation of the 237Np neutron cross sections in the energy range from 10-5 eV to 5 MeV

    International Nuclear Information System (INIS)

    Derrien, H.; Fort, E.

    1979-01-01

    The 237 Np neutron cross-sections have been evaluated in the energy range from thermal to 5 MeV. A set of resonance parameters including a negative level, is recommanded after examination of the available experimental data. This set is used 1) to calculate the cross-sections from the thermal region to 150 ev, and 2) to provide the statistical parameters suitable to the calculations in the unresolved region. At higher energies, the transmission coefficients Te are calculated by the coupled channel optical model code ECIS. They are then used as input in the statistical model code FISINGA. The optical model parameters, including the deformation parameters, are those used by Lagrange for the Pu isotopes, slightly modified to reproduce at 40 KeV the total cross-sections obtained from the pure statistical parameters. The recommendations of Lynn concerning the level density parameters have been used. In this paper we describe the various steps of the evaluation

  14. Neutron induced fission cross section ratios for 232Th, /sup 235,238/U, 237Np, and 239Pu from 1 to 400 MeV

    International Nuclear Information System (INIS)

    Lisowski, P.W.; Ullmann, J.L.; Balestrini, S.J.; Carlson, A.D.; Wasson, O.A.; Hill, N.W.

    1988-01-01

    Time-of-flight measurements of neutron induced fission cross section ratios for 232 Th, /sup 235,238/U, 237 Np, and 239 Pu, were performed using the WNR high intensity spallation neutron source located at Los Alamos National Laboratory. A multiple-plate gas ionization chamber located at a 20-m flight path was used to simultaneously measure the fission rate for all samples over the energy range from 1 to 400 MeV. Because the measurements were made with nearly identical neutron fluxes, we were able to cancel many systematic uncertainties present in previous measurements. This allows us to resolve discrepancies among different data sets. In addition, these are the first neutron-induced fission cross section values for most of the nuclei at energies above 30 MeV. 8 refs., 3 figs

  15. Elastic and Raman scattering of 8.5-11.4 MeV photons from 159Tb, 165Ho, and 237Np

    International Nuclear Information System (INIS)

    Bar-Noy, T.; Moreh, R.

    1977-01-01

    Differential cross sections for elastic and inelastic Raman scattering from the deformed heavy nuclei 159 Tb, 165 Ho and 237 Np were measured at five energies between 8.5 and 11.4 MeV. Angular distributions at four angles between 90 0 and 140 0 for both elastic and inelastic scattering at 9.0 and 11.4 MeV were also measured. The monoenergetic photons were obtained from thermal neutron capture in Ni and Cr. All the angular distributions and the elastic and Raman scattering at the higher energies are in good overall agreement with theoretical predictions. The theory is based on a modified simple rotator model of the giant resonance in which the effect of Delbrueck scattering was included. A trend of both the elastic and Raman scattering at lower energies to be stronger than expected are suggested by the data. However, the ratio between the Raman and elastic scattering seem to be in good agreement with theory throughout the whole energy range. This shows that there is no need to introduce a direct nonresonant component to the imaginary part of the elastic scattering amplitude to explain the experimental data. (Auth.)

  16. Californium Cf-252 for pelvic radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Y; Feola, J M; Tai, D; Wilson, L C; Van Nagell, J R; Yoneda, J

    1978-01-01

    Clinical data about therapy concerning tumors of the female gynecological cancers of the cervix, vagina and uterus are reviewed. Dosimetric, laboratory and radiobiological research data form the basis for an approach to such tumors using Cf-252 as a form of boost brachytherapy. Extreme personnel hazards are a real and important consideration and indicate that maximal containment and isolation procedures should be exercised in its use.

  17. Neutron induced fission cross section ratios for /sup 232/Th, /sup 235,238/U, /sup 237/Np, and /sup 239/Pu from 1 to 400 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Lisowski, P.W.; Ullmann, J.L.; Balestrini, S.J.; Carlson, A.D.; Wasson, O.A.; Hill, N.W.

    1988-01-01

    Time-of-flight measurements of neutron induced fission cross section ratios for /sup 232/Th, /sup 235,238/U, /sup 237/Np, and /sup 239/Pu, were performed using the WNR high intensity spallation neutron source located at Los Alamos National Laboratory. A multiple-plate gas ionization chamber located at a 20-m flight path was used to simultaneously measure the fission rate for all samples over the energy range from 1 to 400 MeV. Because the measurements were made with nearly identical neutron fluxes, we were able to cancel many systematic uncertainties present in previous measurements. This allows us to resolve discrepancies among different data sets. In addition, these are the first neutron-induced fission cross section values for most of the nuclei at energies above 30 MeV. 8 refs., 3 figs.

  18. Neutron spectra from radionuclide sources for cardiac pacemakers

    International Nuclear Information System (INIS)

    Kluge, H.

    1975-01-01

    Neutron spectra from Plutonium 238 radioisotope batteries powering cardiac pacemakers are measured in the energy range above 0.7 MeV. The results are used to calculate radiation doses within a cylindrical phantom. There are only minor differences between the different types of plutonium 238-batteries and californium 252-batteries

  19. Capture and Fission rate of 232-Th, 238-U, 237-Np and 239-Pu from spallation neutrons in a huge block of lead.

    CERN Document Server

    Vlachoudis, Vasilis

    2000-01-01

    The study is centered on the research of the incineration possibility of nuclear waste, by the association of a particle accelerator with a multiplying medium of neutrons, in the project "Energy Amplifier" of C. Rubbia. It consists of the experimental determination of the rates of capture and fission of certain elements (232-Th, 238-U, 237-Np and 239-Pu) subjected to a fluence of fast spallation neutrons. These neutrons are produced by the interaction of high kinetic energy protons (several GeV) provided by the CERN-PS accelerator, on a large lead solid volume. The measurement techniques used in this work, are based on the activation of elements in the lead volume and the subsequent gamma spectroscopy of the activated elements, and also by the detection of fission fragment traces. The development, of a Monte Carlo code makes it possible, on one hand, to better understand the relevant processes, and on the other hand, to validate the code, by comparison with measurements, for the design and the construction of...

  20. Single-event burnout of power MOSFET devices for satellite application

    International Nuclear Information System (INIS)

    Xue Yuxiong; Tian Kai; Cao Zhou; Yang Shiyu; Liu Gang; Cai Xiaowu; Lu Jiang

    2008-01-01

    Single-event burnout (SEB) sensitivity was tested for power MOSFET devices, JTMCS081 and JTMCS062, which were made in Institute of Microelectronics, Chinese Academy of Sciences, using californium-252 simulation source. SEB voltage threshold was found for devices under test (DUT). It is helpful for engineers to choose devices used in satellites. (authors)

  1. Radioactive materials production

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The Radiochemical Processing Plant (RPP) at ORNL has served as the national repository and distribution center for 233 U for > 20 years. Several hundred kilograms of uranium, containing approximately 90 to 98% 233 U, are stored there in the form of metal, oxides, and nitrate solutions. All of these uranium materials contain small, but significant, concentrations of 232 U, ranging from 2 to 225 ppm. Most of the radioactivity associated with the 233 U comes from the decay daughters of 232 U (74-year half-life). The 252 Cf Industrial Sales/Loan Program involves loans of 252 Cf neutron sources to agencies of the US Government and sales of 252 Cf as the bulk oxide and as palladium-californium alloy pellets and wires. The program has been operated since 1968 in temporary facilities at the Savannah River Laboratory (SRL). The obsolete hot-cell facilities at SRL are now being decommissioned, and the program activities are being transferred to ORNL's Californium Facility in Bldg. 7930, which is managed by the staff of the Transuranium Processing Plant

  2. Validation of the MCNP-DSP Monte Carlo code for calculating source-driven noise parameters of subcritical systems

    International Nuclear Information System (INIS)

    Valentine, T.E.; Mihalczo, J.T.

    1995-01-01

    This paper describes calculations performed to validate the modified version of the MCNP code, the MCNP-DSP, used for: the neutron and photon spectra of the spontaneous fission of californium 252; the representation of the detection processes for scattering detectors; the timing of the detection process; and the calculation of the frequency analysis parameters for the MCNP-DSP code

  3. Magnetic measurements of the transuranium elements. Progress report, January 1, 1984-December 31, 1984

    International Nuclear Information System (INIS)

    Huray, P.G.; Nave, S.E.

    1984-01-01

    Measurements of the magnetic properties of dhcp californium-249 metal indicated the presence of three regions of differing magnetic character. Additional measurements are also reported. Magnetic moments and valence states of terbium in TbF 3 , BaTbO 3 , and TbO 1 8 are discussed. Progress on high-field operation of the micro-magnetic susceptometer is reported

  4. Preparation and study of elemental californium-249

    International Nuclear Information System (INIS)

    Noe, M.; Peterson, J.R.

    1975-01-01

    Bulk samples of 249 Cf metal were prepared on the 10 μg scale via the Li metal vapor reduction of 249 CfF 3 . Above about 725 0 C elemental Cf exhibits a face-centered cubic (fcc) structure with an average, room-temperature lattice parameter of 5.75(1)A. Between about 600 0 C and 725 0 C, the stable form of Cf metal is another fcc structure with an average, room-temperature lattice parameter of 4.94(1)A. Below 600 0 C metallic Cf exhibits a double hexagonal closest packed (dhcp) structure with average, room temperature lattice parameters of a 0 = 3.39(1)A and c 0 = 11.01(5)A. By comparison of the metallic radii calculated for these three forms with those of the receding transuranium elements, it is suggested that the two, lower temperature modifications represent Cf with a metallic valence of three, while the highest temperature form represents a metallic valence of two. Although the data reported here are from the most complete study to date of elemental Cf, the limitations accompanying such microscale research are duly noted. (U.S.)

  5. Solid-State Neutron Multiplicity Counting System Using Commercial Off-the-Shelf Semiconductor Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Rozhdestvenskyy, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-08-09

    This work iterates on the first demonstration of a solid-state neutron multiplicity counting system developed at Lawrence Livermore National Laboratory by using commercial off-the-shelf detectors. The system was demonstrated to determine the mass of a californium-252 neutron source within 20% error requiring only one-hour measurement time with 20 cm2 of active detector area.

  6. Determination of neutron resonance parameters of Neptunium 237 between 0 and 500 eV. The covariance matrices of statistical and of systematic origin, relating the resonance parameters, are also given; Determination des parametres des resonances neutroniques du neptunium 237, en dessous de 500eV, et obtention des matrices de covariances statistiques et systematiques entre les parametres de ces resonances

    Energy Technology Data Exchange (ETDEWEB)

    Lepretre, A.; Herault, N. [CEA Saclay, Dept. d' Astrophysique de Physique des Particules, de Physique Nucleaire et de l' Instrumentation Associee, 91- Gif sur Yvette (France); Brusegan, A.; Noguere, G.; Siegler, P. [Institut des Materiaux et des Metrologies - IRMM, Joint Research Centre, Gell (Belgium)

    2002-12-01

    This report is a follow up of the report CEA DAPNIA/SPHN-99-04T of Vincent Gressier. In the frame of a collaboration between the 'Commissariat a l'Energie Atomique (CEA)' and the Institute for Reference Materials and Measurement (IRMM, Geel, Belgique), the resonance parameters of neptunium 237 have been determined in the energy interval between 0 and 500 eV. These parameters have been obtained by using the Refit code in analysing simultaneously three transmission experiments. The covariance matrix of statistical origin is provided. A new method, based on various sensitivity studies is proposed for determining also the covariance matrix of systematic origin, relating the resonance parameters. From an experimental viewpoint, the study indicated that, with a large probability, the background spectrum has structure. A two dimensional profiler for the neutron density has been proved feasible. Such a profiler could, among others, demonstrate the existence of the structured background. (authors)

  7. Citric complexes of trivalent cerium and berkelium

    International Nuclear Information System (INIS)

    Boulhassa, S.

    1977-01-01

    The extraction by thenoyltrifluoroacetone (TTA) in benzene of trivalent cerium, berkelium and californium, at the indicator scale, hydrolysis and complexation by citric acid of these cations are studied. The radionuclides used were 144 Ce, 249 Bk and 249 Cf respectively γ, β and α emitters. The solvent extraction technique of the elements by TTA in benzene from a perchloric medium at the ionic stength 0.1 was employed. The distribution coefficients D were measured by the γ, β or α radiometry. Cerium and berkelium, which have a comparable redox behavior, show in solution a relatively stable valency IV. Therefore the study by solvent extraction of their trivalent form required the standing up of complete reducing conditions of these elements and their stabilization in solution at the valency III. The thermodynamic data obtained for berkelium and californium contribute to understand the chemistry of these elements and permit to complete the third 'tetrad branch' of 5f elements from Cm 3+ to Es 3+ . This tetrad effect is a manifestation of thermodynamic consequence of the 'nephelauxetic effect'. As for Ce(III), the data confirm the pronounced acid property and may be show no neglected ligand effect for f 1 configuration [fr

  8. Wind-tunnel investigation of longitudinal and lateral-directional stability and control characteristics of a 0.237-scale model of a remotely piloted research vehicle with a thick, high-aspect-ratio supercritical wing

    Science.gov (United States)

    Byrdsong, T. A.; Brooks, C. W., Jr.

    1980-01-01

    A 0.237-scale model of a remotely piloted research vehicle equipped with a thick, high-aspect-ratio supercritical wing was tested in the Langley 8-foot transonic tunnel to provide experimental data for a prediction of the static stability and control characteristics of the research vehicle as well as to provide an estimate of vehicle flight characteristics for a computer simulation program used in the planning and execution of specific flight-research mission. Data were obtained at a Reynolds number of 16.5 x 10 to the 6th power per meter for Mach numbers up to 0.92. The results indicate regions of longitudinal instability; however, an adequate margin of longitudinal stability exists at a selected cruise condition. Satisfactory effectiveness of pitch, roll, and yaw control was also demonstrated.

  9. Directed evolution of the periodic table: probing the electronic structure of late actinides.

    Science.gov (United States)

    Marsh, M L; Albrecht-Schmitt, T E

    2017-07-25

    Recent investigations of the coordination chemistry and physical properties of berkelium (Z = 97) and californium (Z = 98) have revealed fundamental differences between post-curium elements and lighter members of the actinide series. This review highlights these developments and chronicles key findings and concepts from the last half-century that have helped usher in a new understanding of the evolution of electronic structure in the periodic table.

  10. Properties of neutron sources

    International Nuclear Information System (INIS)

    1987-03-01

    The Conference presentations were divided into sessions devoted to the following topics: white neutron sources, primarily pulsed (6 papers); fast neutron fields (5 papers); Californium-252 prompt fission neutron spectra (14 papers); monoenergetic sources and filtered beams (11 papers); 14 MeV neutron sources (10 papers); selected special application (one paper); and a general interest session (4 papers). Individual abstracts were prepared separately for the papers

  11. The Effect of Radiation Dose and Chemotherapy on Overall Survival in 237 Patients With Stage III Non-Small-Cell Lung Cancer

    International Nuclear Information System (INIS)

    Wang Li; Correa, Candace R.; Zhao Lujun; Hayman, James; Kalemkerian, Gregory P.; Lyons, Susan; Cease, Kemp; Brenner, Dean; Kong Fengming

    2009-01-01

    Purpose: To study the effects of radiation dose, chemotherapy, and their interaction in patients with unresectable or medically inoperable Stage III non-small-cell lung cancer (NSCLC). Methods and Materials: A total of 237 consecutive Stage III NSCLC patients were evaluated. Median follow-up was 69.0 months. Patients were treated with radiation therapy (RT) alone (n = 106), sequential chemoradiation (n = 69), or concurrent chemoradiation (n = 62). The primary endpoint was overall survival (OS). Radiation dose ranged from 30 to 102.9 Gy (median 60 Gy), corresponding to a bioequivalent dose (BED) of 39 to 124.5 Gy (median 72 Gy). Results: The median OS of the entire cohort was 12.6 months, and 2- and 5-year survival rates were 22.4% and 10.0%, respectively. Multivariable Cox regression model demonstrated that Karnofsky performance status (p = 0.020), weight loss < 5% (p = 0.017), chemotherapy (yes vs. no), sequence of chemoradiation (sequential vs. concurrent; p < 0.001), and BED (p < 0.001) were significant predictors of OS. For patients treated with RT alone, sequential chemoradiation, and concurrent chemoradiation, median survival was 7.4, 14.9, and 15.8 months, and 5-year OS was 3.3%, 7.5%, and 19.4%, respectively (p < 0.001). The effect of higher radiation doses on survival was independent of whether chemotherapy was given. Conclusion: Radiation dose and use of chemotherapy are independent predictors of OS in Stage III NSCLC, and concurrent chemoradiation is associated with the best survival. There is no interaction between RT dose and chemotherapy.

  12. Computer-assisted nuclear fuel manufacture

    International Nuclear Information System (INIS)

    Maloney, J.P.; Schaumann, S.M.; Stone, E.

    1976-01-01

    At the ERDA Savannah River Plant, a process monitor, which incorporates an online digital computer, assists in manufacturing fuel elements used to produce nuclides such as plutonium, tritium, and californium in the plant's nuclear reactors. Also, inventory functions assist in safeguarding fissile material and protecting against accidental nuclear criticality. Terminals at strategic locations throughout the process area enable production operators to send and receive instructions and information on each manufacturing step

  13. Automated absolute activation analysis with californium-252 sources

    International Nuclear Information System (INIS)

    MacMurdo, K.W.; Bowman, W.W.

    1978-09-01

    A 100-mg 252 Cf neutron activation analysis facility is used routinely at the Savannah River Laboratory for multielement analysis of many solid and liquid samples. An absolute analysis technique converts counting data directly to elemental concentration without the use of classical comparative standards and flux monitors. With the totally automated pneumatic sample transfer system, cyclic irradiation-decay-count regimes can be pre-selected for up to 40 samples, and samples can be analyzed with the facility unattended. An automatic data control system starts and stops a high-resolution gamma-ray spectrometer and/or a delayed-neutron detector; the system also stores data and controls output modes. Gamma ray data are reduced by three main programs in the IBM 360/195 computer: the 4096-channel spectrum and pertinent experimental timing, counting, and sample data are stored on magnetic tape; the spectrum is then reduced to a list of significant photopeak energies, integrated areas, and their associated statistical errors; and the third program assigns gamma ray photopeaks to the appropriate neutron activation product(s) by comparing photopeak energies to tabulated gamma ray energies. Photopeak areas are then converted to elemental concentration by using experimental timing and sample data, calculated elemental neutron capture rates, absolute detector efficiencies, and absolute spectroscopic decay data. Calculational procedures have been developed so that fissile material can be analyzed by cyclic neutron activation and delayed-neutron counting procedures. These calculations are based on a 6 half-life group model of delayed neutron emission; calculations include corrections for delayed neutron interference from 17 O. Detection sensitivities of 239 Pu were demonstrated with 15-g samples at a throughput of up to 140 per day. Over 40 elements can be detected at the sub-ppM level

  14. Savannah River Plant californium-252 Shuffler electronics manual

    International Nuclear Information System (INIS)

    Bourret, S.C.; Crane, T.W.; Eccleston, G.W.; Gallegos, E.A.; Garcia, D.L.

    1980-03-01

    Detailed information is presented in this report, an electronics manual for the Savannah River Plant Shuffler, about the electronics associated with the various control and data acquisition functions of the Shuffler subsystems. Circuit diagrams, interconnection information, and details about computer control and programming are included

  15. Savannah River Plant Californium-252 Shuffler software manual

    International Nuclear Information System (INIS)

    Johnson, S.S.; Crane, T.W.; Eccleston, G.W.

    1979-03-01

    A software manual for operating the Savannah River Plant Shuffler nondestructive assay instrument is presented. The procedures for starting up the instrument, making assays, calibrating, and checking the performance of the hardware units are described. A list of the error messages with an explanation of the circumstances prompting the message and possible corrective measures is given. A summary of the software package is included showing the names and contents of the files and subroutines. The procedure for modifying the software package is outlined

  16. Coulex fission of 234U, 235U, 237Np, and 238Np studied within the SOFIA experimental program

    International Nuclear Information System (INIS)

    Martin, Julie-Fiona

    2014-01-01

    SOFIA (Studies On FIssion with Aladin) is an experimental project which aims at systematically measuring the fission fragments' isotopic yields as well as their total kinetic energy, for a wide variety of fissioning nuclei. The PhD work presented in this dissertation takes part in the SOFIA project, and covers the fission of nuclei in the region of the actinides: 234 U, 235 U, 237 Np and 238 Np. The experiment is led at the heavy-ion accelerator GSI in Darmstadt, Germany. This facility provides intense relativistic primary beam of 238 U. A fragmentation reaction of the primary beam permits to create a secondary beam of radioactive ions, some of which the fission is studied. The ions of the secondary beam are sorted and identified through the FR-S (Fragment Separator), a high resolution recoil spectrometer which is tuned to select the ions of interest.The selected - fissile - ions then fly further to Cave-C, an experimental area where the fission experiment itself takes place. At the entrance of the cave, the secondary beam is excited by Coulomb interaction when flying through an target; the de-excitation process involves low-energy fission. Both fission fragments fly forward in the laboratory frame, due to the relativistic boost inferred from the fissioning nucleus.A complete recoil spectrometer has been designed and built by the SOFIA collaboration in the path of the fission fragments, around the existing ALADIN magnet. The identification of the fragments is performed by means of energy loss, time of flight and deviation in the magnet measurements. Both fission fragments are fully (in mass and charge) and simultaneously identified.This document reports on the analysis performed for (1) the identification of the fissioning system, (2) the identification of both fission fragments, on an event-by-event basis, and (3) the extraction of fission observables: yields, TKE, total prompt neutron multiplicity. These results, concerning the actinides, are discussed, and

  17. Determination of neutron resonance parameters of Neptunium 237 between 0 and 500 eV. The covariance matrices of statistical and of systematic origin, relating the resonance parameters, are also given

    International Nuclear Information System (INIS)

    Lepretre, A.; Herault, N.; Brusegan, A.; Noguere, G.; Siegler, P.

    2002-12-01

    This report is a follow up of the report CEA DAPNIA/SPHN-99-04T of Vincent Gressier. In the frame of a collaboration between the 'Commissariat a l'Energie Atomique (CEA)' and the Institute for Reference Materials and Measurement (IRMM, Geel, Belgique), the resonance parameters of neptunium 237 have been determined in the energy interval between 0 and 500 eV. These parameters have been obtained by using the Refit code in analysing simultaneously three transmission experiments. The covariance matrix of statistical origin is provided. A new method, based on various sensitivity studies is proposed for determining also the covariance matrix of systematic origin, relating the resonance parameters. From an experimental viewpoint, the study indicated that, with a large probability, the background spectrum has structure. A two dimensional profiler for the neutron density has been proved feasible. Such a profiler could, among others, demonstrate the existence of the structured background. (authors)

  18. Investigation of Neutron Spectra and Transmutation of ^{129}I, ^{237}Np and Other Nuclides with 1.5 GeV Protons from the Dubna Nuclotron Using the Electronuclear Setup "Energy plus Transmutation"

    CERN Document Server

    Krivopustov, M I; Balabekyan, A R; Batusov, Yu A; Bielewicz, M; Brandt, R; Chaloun, P; Chultem, D; Dwivedi, K K; Elishev, A F; Fragopoulou, M; Henzl, V; Henzlová, D; Kalinnikov, V G; Kievets, M K; Krása, A; Krizek, F; Kugler, A; Manolopoulou, Metaxia; Mariin, I I; Nourreddine, A; Odoj, R; Pavliouk, A V; Pronskikh, V S; Robotham, H; Siemon, K; Szuta, M; Stegailov, V I; Solnyshkin, A A; Sosnin, A N; Stoulos, S; Tsoupko-Sitnikov, V M; Tumendelger, T; Wojecehowski, A; Wagner, V; Wan, J S; Westmeier, W; Zamani-Valasiadou, M; Kumawat, H; Kumar, V; Zaverioukha, O S; Zhuk, I V

    2004-01-01

    Experiments which are part of the scientific program "Investigations of physical aspects of electronuclear method of energy production and transmutation for radioactive waste of atomic energetics using relativistic beams from the JINR Synchrophasotron/Nuclotron" (project "Energy plus Transmutation") are described. A large lead target surrounded by a four-section uranium blanket with total weight of 206.4 kg natural uranium was irradiated with 1.5 GeV protons from the new cryogenic accelerator Nuclotron. Radiochemical sensors were exposed to the secondary particle fluences inside and on top of the target assembly. Two long-lived radioactive waste of atomic energetics sensors ^{129}I and ^{237}Np (approximately 1 g weight each) and stable nuclides ^{27}Al, ^{59}Co, ^{127}I, ^{139}La, ^{197}Au and ^{209}Bi as well as natural and enriched uranium were used. In addition, various solid state nuclear track detectors and nuclear emulsions were exposed simultaneously. The experimental results confirm the theoretical e...

  19. Computer-assisted nuclear fuel manufacture

    International Nuclear Information System (INIS)

    Maloney, J.P.; Schaumann, C.M.; Stone, E.

    1976-06-01

    At the ERDA Savannah River Plant, a process monitor, which incorporates an online digital computer, assists in manufacturing fuel elements used to produce nuclides such as plutonium, tritium, and californium in the plant's nuclear reactors. Also, inventory functions assist in safeguarding fissile material and protecting against accidental nuclear criticality. Terminals at strategic locations throughout the process area enable production operators to send and receive instructions and information on each manufacturing step. 11 fig

  20. The fission cross sections of 230Th, 232Th, 233U, 234U, 236U, 238U, 237Np, 239Pu and 242Pu relative 235U at 14.74 MeV neutron energy

    International Nuclear Information System (INIS)

    Meadows, J.W.

    1986-12-01

    The measurement of the fission cross section ratios of nine isotopes relative to 235 U at an average neutron energy of 14.74 MeV is described with particular attention to the determination of corrections and to sources of error. The results are compared to ENDF/B-V and to other measurements of the past decade. The ratio of the neutron induced fission cross section for these isotopes to the fission cross section for 235 U are: 230 Th - 0.290 +- 1.9%; 232 Th - 0.191 +- 1.9%; 233 U - 1.132 +- 0.7%; 234 U - 0.998 +- 1.0%; 236 U - 0.791 +- 1.1%; 238 U - 0.587 +- 1.1%; 237 Np - 1.060 +- 1.4%; 239 Pu - 1.152 +- 1.1%; 242 Pu - 0.967 +- 1.0%. 40 refs., 11 tabs., 9 figs

  1. 234 - 237_Uduma_Elementall

    African Journals Online (AJOL)

    pc

    risks from exposure to geological materials associa with mining ... alue both to the mining industry and to the health of the commun cal exploitation ... ent production, ceramics petroleum .... controls can minimize exposures to workers and.

  2. Comment: 237 [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available for Life Science licensed under CC Attribution2.1 Japan 絵や写真の投稿もできます。右は、没になったティラノザウルス(目がかわいい)です。 ttamura 2008/11/11 12:11:40 2011/09/14 21:10:36 ...

  3. The protective cell petrus for the production of californium 252; Cellule blindee petrus pour la production et l'etude du californium 252

    Energy Technology Data Exchange (ETDEWEB)

    Sontag, R; Berger, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-07-01

    The alpha, beta, gamma, neutron cell which is described in the present paper is devoted to the transplutonium element production and study. It is located at the CEN in Fontenay-aux-Roses (France). The 4 feet ordinary concrete shielding made of stacked blocs allows the manipulation of radioactive sources as high as 1000 curies of 1 MeV gamma rays and with a fast neutrons flux of 10{sup 9} n.cm{sup -2}.s{sup -1}. The airtight alpha containment box is equipped with two transfer systems, one consists of a parallelepiped shaped airtight box located in a turntable, the other uses standard cylindrical containers made of polyethylene. The general equipment and the main setting up are also described. (authors) [French] La cellule alpha, beta, gamma, neutron, qui fait l'objet du present article, est destinee a la production et a l'etude des elements transplutoniens. Elle est construite au C.E.N. de Fontenay-aux-Roses (France). La protection biologique, calculee pour une activite de 1000 curies de rayonnement gamma d'energie 1 MeV accompagnee d'un flux de neutrons rapides de 10{sup 9}/cm{sup 2}s, est constituee par des parois en beton de 1,20 m d'epaisseur. L'enceinte alpha est une boite etanche qui comporte devx systemes de transferts: l'un consiste en une boite parallelepipedique etanche logee dans un barillet, l'autre fait appel a des recipients cylindriques standard en polyethylene. L'equipement general et les installations les plus importantes sont ensuite decrits. (auteurs)

  4. Heavy ion tests on programmable VLSI

    International Nuclear Information System (INIS)

    Provost-Grellier, A.

    1989-11-01

    The radiation from space environment induces operation damages in onboard computers systems. The definition of a strategy, for the Very Large Scale Integrated Circuitry (VLSI) qualification and choice, is needed. The 'upset' phenomena is known to be the most critical integrated circuit radiation effect. The strategies for testing integrated circuits are reviewed. A method and a test device were developed and applied to space applications candidate circuits. Cyclotron, synchrotron and Californium source experiments were carried out [fr

  5. Charge breeding of radioactive isotopes at the CARIBU facility with an electron beam ion source

    Science.gov (United States)

    Vondrasek, R. C.; Dickerson, C. A.; Hendricks, M.; Ostroumov, P.; Pardo, R.; Savard, G.; Scott, R.; Zinkann, G.

    2018-05-01

    An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed at Argonne National Laboratory as part of the californium rare ion breeder upgrade. For the past year, the EBIS-CB has been undergoing commissioning as part of the ATLAS accelerator complex. It has delivered both stable and radioactive beams with A/Q 18% into a single charge state. The operation of this device, challenges during the commissioning phase, and future improvements will be discussed.

  6. Safety analysis report for packaging: neutron shipping cask, model 0.5T

    International Nuclear Information System (INIS)

    Peterson, R.T.

    1976-01-01

    The Safety Analysis Report for Packaging demonstrates that the neutron shipping cask can safely transport, in solid or powder form, all isotopes of uranium, plutonium, americium, curium, berkelium, californium, einsteinium, and fermium. The shipping cask and its contents are described. It also evaluates transport conditions, structural parameters (e.g., load resistance, pressure and impact effects, lifting and tiedown devices), and shielding. Finally, it discusses compliance with Chapter 0529 of the Energy Research and Development Administration Manual

  7. NWIS casting measurements taken during demonstrations to Russian visitors

    International Nuclear Information System (INIS)

    Mullens, J.A.; Valentine, T.E.; Mihalczo, J.T.

    1998-01-01

    This report describes a set of NWIS measurements made during demonstrations to Russian visitors on August 28, 1997. These measurements will be given to the Russian visitors from Arzamus-16 as part of their NWIS training (part of a DOE laboratory-to-laboratory exchange program). These measurements are made on standard highly enriched Uranium annular castings (as used for storage). Associated NWIS calibration runs were made in air (no casting, just the NWIS Californium source and detectors)

  8. Health physics aspects of 252Cf

    International Nuclear Information System (INIS)

    Bhagwat, A.M.

    1974-01-01

    After briefly describing the methods of production, radioactive, chemical and biological properties of californium-252, its health physics aspects are reviewed in detail. Its external and internal radiation hazards can be minimised through control of radiation and contamination and proper shield design. Use of various shielding materials is evaluated. The following aspects are also discussed : (1) radiation detectors for neutrons and gamma radiation (2) personnel monitoring techniques (3) bioassay and (4) storage and transportation. (M.G.B.)

  9. Survey of potential markets for devices using Californium-252

    International Nuclear Information System (INIS)

    Permar, P.H.

    1975-01-01

    Potential applications for devices or systems containing 252 Cf in the years from 1975 to 1980 are estimated. The estimated number of devices and associated business value were derived from a survey of 46 industrial, educational and governmental organizations conducted from Jan. to May, 1975. Applications for devices and systems based on 252 Cf are expected to increase by a factor of 7 in the 6-y period from 1975 to 1980. The annual business value of 252 Cf devices should increase from 1.5 million dollars in 1975 to 10.8 million dollars in 1980. The potential European market should be several times as large as the US market, based on actual sales of 252 Cf, which have been two to four times greater in Europe than in the US

  10. Californium-252 interstitial implants in carcinoma of the tongue

    International Nuclear Information System (INIS)

    Vtyurin, B.M.; Ivanov, V.N.; Medvedev, V.S.; Galantseva, G.F.; Abdulkadyrov, S.A.; Ivanova, L.F.; Petrovskaya, G.A.; Plichko, V.I.

    1985-01-01

    A clinical study using 252 Cf sources in brachytherapy of tumors began in the Research Institute of Medical Radiology of the Academy of Medical Sciences of the USSR in 1973. 252 Cf afterloading cells were utilized by the method of simple afterloading. Dosimetry and radiation protection of medical personnel were developed. To substantiate optimal therapeutic doses of 252 Cf neutrons, a correlation of dose, time, and treatment volume factors with clinical results of 252 Cf interstitial implants in carcinoma of the tongue for 47 patients with a minimum follow-up period of 1 year was studied. Forty-nine interstitial implants have been performed. Seventeen patients received 252 Cf implants alone (Group I), 17 other patients received 252 Cf implants in combination with external radiation (Group II), and 15 patients were treated with interstitial implants for recurrent or residual tumors (Groups III). Complete regression of carcinoma of the tongue was obtained in 48 patients (98%). Thirteen patients (27%) developed radiation necrosis. The therapeutic dose of neutron radiation from 252 Cf sources in interstitial radiotherapy of primary tongue carcinomas (Group I) was found to be 7 to 9 Gy. Optimal therapeutic neutron dose in combined interstitial and external radiotherapy of primary tumors (Group II) was 5 to 6 Gy with an external radiation dose of 40 Gy. For recurrent and residual tumors (Group III), favorable results were obtained with tumor doses of 6.5 to 7 Gy

  11. Undergraduate experiments using the neutron radiation from californium-252

    International Nuclear Information System (INIS)

    Rossel, J.; Golecki, I.

    1976-01-01

    Three experiments designed to demonstrate and measure several properties of the neutron radiation emitted by a 3μg 252 Cf source are described. The experiments constitute a special project carried out by a third-year undergraduate student at the Institute of Physics of the University of Neuchatel. The 252 Cf source is enclosed in a shield which allows a pencil of fast neutrons to pass through a central tube, while reducing the ambient radiation below the tolerance level. The shield consists of layers of borated paraffin wax, iron and cadmium. The first experiment uses an air-alcohol diffusion cloud chamber for the demonstration of tracks of recoil protons produced by the neutrons. Semi-quantitative measurements of track lengths give the correct order of magnitude of the proton energies. In the second experiment a liquid scintillator detector is used to scan the beam profile across the radiation shield enclosing the source. A pulse-shape-discrimination system discriminates between neutrons and gamma photons. The third experiment makes use of the nuclear emulsion technique to study the neutron energy distribution of 252 Cf. Preliminary results are compared with published values. (author)

  12. Safety analysis report for packaging: neutron shipping cask, model 4T

    International Nuclear Information System (INIS)

    Peterson, R.T.

    1977-01-01

    This Safety Analysis Report for Packaging demonstrates that the neutron shipping cask can safely transport, in solid or powder form, all isotopes of uranium, plutonium, americium, curium, berkelium, californium, einsteinium, and fermium. The cask and its contents are described. It also evaluates transport conditions, structural parameters (e.g., load resistance, pressure and impact effects, lifting and tiedown devices), and shielding. Finally, it discusses compliance with Chapter 0529 of the Energy Research and Development Administration Manual, Safety Standards for the Packaging of Fissile and Other Radioactive Materials

  13. Method for measuring multiple scattering corrections between liquid scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Verbeke, J.M., E-mail: verbeke2@llnl.gov; Glenn, A.M., E-mail: glenn22@llnl.gov; Keefer, G.J., E-mail: keefer1@llnl.gov; Wurtz, R.E., E-mail: wurtz1@llnl.gov

    2016-07-21

    A time-of-flight method is proposed to experimentally quantify the fractions of neutrons scattering between scintillators. An array of scintillators is characterized in terms of crosstalk with this method by measuring a californium source, for different neutron energy thresholds. The spectral information recorded by the scintillators can be used to estimate the fractions of neutrons multiple scattering. With the help of a correction to Feynman's point model theory to account for multiple scattering, these fractions can in turn improve the mass reconstruction of fissile materials under investigation.

  14. Nuclear assay of coal. Volume 1. Coal composition by prompt neutron activation analysis: basic experiments. Final report

    International Nuclear Information System (INIS)

    Reynolds, G.; Bozorganesh, H.; Elias, E.; Gozani, T.; Maung, T.; Orphan, V.

    1979-01-01

    Using californium-252 as a source of exciting neutrons, prompt gamma photons emitted by elemental nuclei in the coal have been measured using several detectors, including sodium--iodide and germanium--lithium. Several coal types, including bituminous, subbituminous lignite and anthracite were crushed to various top sizes and analyzed carefully be traditional ASTM wet chemistry techniques at two or three different laboratories. The elements (sulfur, hydrogen, carbon, aluminum, silicon, iron, calcium, sodium, nitrogen, and chlorine) were determined by prompt neutron activations and the quantities compared with those of the wet chemical analyses

  15. Actinides

    International Nuclear Information System (INIS)

    Martinot, L.; Fuger, J.

    1985-01-01

    The oxidation behavior of the actinides is explained on the basis of their electronic structure. The actinide elements, actinium, thorium, protactinium, uranium, neptunium, plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium, and laurencium are included. For all except the last three elements, the points of discussion are oxidation states, Gibbs energies and potentials, and potential diagram for the element in acid solution; and thermodynamic properties of these same elements are tabulated. References are cited following discussion of each element with a total of 97 references being cited. 13 tables

  16. TMFunction data: 237 [TMFunction[Archive

    Lifescience Database Archive (English)

    Full Text Available HC. J Biol Chem. 2000 Jul 14;275(28):21017-24 mutagenesis ... affinity chromatography 1AJJ ... LDLR_HUMAN (P01130) Helix ... ligand binding site; surface exposed; acidic residue; conserved

  17. 48 CFR 237.7301 - Definitions.

    Science.gov (United States)

    2010-10-01

    ... means any public or private post-secondary school, junior college, college, university, or other degree... of study at any level beyond high school. (b) Nonprofit organization means any organization described... good standing in a curriculum designed to lead to the granting of a recognized degree, during the term...

  18. The accumulation of plutonium by the European lobster (Homarus gammarus L.)

    International Nuclear Information System (INIS)

    Swift, D.J.

    1992-01-01

    For 237 Pu accumulation from seawater, the whole body concentration factors (CFs) for juvenile lobsters at 18 o C did not exceed 250 over the 49 days of the study. Most 237 Pu was accumulated by the gills and exoskeleton. Since homarid lobsters eat their exuviae after ecdysis, the whole body 237 Pu content of recently moulted lobsters was also a function of the amount of 237 Pu ingested with the exuviae. Consequently, organ/tissue content and CF values for individual lobsters reflected both the time since their last moult and their exposure time to 237 Pu. These factors precluded the calculation of mean whole body CF values or the accurate estimate of a mean steady state (C ss ) CF value. Juvenile lobsters retained significantly more 237 Pu from labelled food at 7-10 o C than at 18 o C. At 7 o C, the biological half time for assimilated 237 Pu was about 28 days, at 10 o C about 15 days and at 18 o C about 8 days. Very little 237 Pu was transported from the gut to the internal tissues (about 1%); most was retained in the hepatopancreas. (author)

  19. Theoretical analyses of (n,xn) reactions on sup 235 U, sup 238 U, sup 237 Np, and sup 239 Pu for ENDF/B-VI

    Energy Technology Data Exchange (ETDEWEB)

    Young, P.G.; Arthur, E.D.

    1991-01-01

    Theoretical analyses were performed of neutron-induced reactions on {sup 235}U, {sup 238}U, {sup 237}Np, and {sup 239}Pu between 0.01 and 20 MeV in order to calculate neutron emission cross sections and spectra for ENDF/B-VI evaluations. Coupled-channel optical model potentials were obtained for each target nucleus by fitting total, elastic, and inelastic scattering cross section data, as well as low-energy average resonance data. The resulting deformed optical model potentials were used to calculate direct (n,n{prime}) cross sections and transmission coefficients for use in Hauser-Feshbach statistical theory analyses. A fission model with multiple barrier representation, width fluctuation corrections, and preequilibrium corrections were included in the analyses. Direct cross sections for higher-lying vibrational states were calculated using DWBA theory, normalized using B(E{ell}) values determined from (d,d{prime}) and Coulomb excitation data, where available, and from systematics otherwise. Initial fission barrier parameters and transition state density enhancements appropriate to the compound systems involved were obtained from previous analyses, especially fits to charged-particle fission probability data. The parameters for the fission model were adjusted for each target system to obtain optimum agreement with direct (n,f) cross section measurements, taking account of the various multichance fission channels, that is, the different compound systems involved. The results from these analyses were used to calculate most of the neutron (n,n), (n,n{prime}), and (n,xn) cross section data in the ENDF/B/VI evaluations for the above nuclei, and all of the energy-angle correlated spectra. The deformed optical model and fission model parameterizations are described. Comparisons are given between the results of these analyses and the previous ENDF/B-V evaluations as well as with the available experimental data. 14 refs., 3 figs., 1 tab.

  20. The protective cell petrus for the production of californium 252

    International Nuclear Information System (INIS)

    Sontag, R.; Berger, R.

    1967-01-01

    The alpha, beta, gamma, neutron cell which is described in the present paper is devoted to the transplutonium element production and study. It is located at the CEN in Fontenay-aux-Roses (France). The 4 feet ordinary concrete shielding made of stacked blocs allows the manipulation of radioactive sources as high as 1000 curies of 1 MeV gamma rays and with a fast neutrons flux of 10 9 n.cm -2 .s -1 . The airtight alpha containment box is equipped with two transfer systems, one consists of a parallelepiped shaped airtight box located in a turntable, the other uses standard cylindrical containers made of polyethylene. The general equipment and the main setting up are also described. (authors) [fr

  1. Human Leukocyte Antigen-A, B, C, DRB1, and DQB1 Allele and Haplotype Frequencies in a Subset of 237 Donors in the South African Bone Marrow Registry

    Directory of Open Access Journals (Sweden)

    Mqondisi Tshabalala

    2018-01-01

    Full Text Available Human leukocyte antigen- (HLA- A, HLA-B, HLA-C, HLA-DRB1, and HLA-DQB1 allele and haplotype frequencies were studied in a subset of 237 volunteer bone marrow donors registered at the South African Bone Marrow Registry (SABMR. Hapl-o-Mat software was used to compute allele and haplotype frequencies from individuals typed at various resolutions, with some alleles in multiple allele code (MAC format. Four hundred and thirty-eight HLA-A, 235 HLA-B, 234 HLA-DRB1, 41 HLA-DQB1, and 29 HLA-C alleles are reported. The most frequent alleles were A∗02:02g (0.096, B∗07:02g (0.082, C∗07:02g (0.180, DQB1∗06:02 (0.157, and DRB1∗15:01 (0.072. The most common haplotype was A∗03:01g~B∗07:02g~C∗07:02g~DQB1∗06:02~DRB1∗15:01 (0.067, which has also been reported in other populations. Deviations from Hardy-Weinberg equilibrium were observed in A, B, and DRB1 loci, with C~DQB1 being the only locus pair in linkage disequilibrium. This study describes allele and haplotype frequencies from a subset of donors registered at SABMR, the only active bone marrow donor registry in Africa. Although the sample size was small, our results form a key resource for future population studies, disease association studies, and donor recruitment strategies.

  2. The accumulation of plutonium by the European lobster (Homarus gammarus L. )

    Energy Technology Data Exchange (ETDEWEB)

    Swift, D J [Ministry of Agriculture, Fisheries and Food, Lowestoft (United Kingdom). Directorate of Fisheries Research

    1992-01-01

    For {sup 237}Pu accumulation from seawater, the whole body concentration factors (CFs) for juvenile lobsters at 18{sup o}C did not exceed 250 over the 49 days of the study. Most {sup 237}Pu was accumulated by the gills and exoskeleton. Since homarid lobsters eat their exuviae after ecdysis, the whole body {sup 237}Pu content of recently moulted lobsters was also a function of the amount of {sup 237}Pu ingested with the exuviae. Consequently, organ/tissue content and CF values for individual lobsters reflected both the time since their last moult and their exposure time to {sup 237}Pu. These factors precluded the calculation of mean whole body CF values or the accurate estimate of a mean steady state (C{sub ss}) CF value. Juvenile lobsters retained significantly more {sup 237}Pu from labelled food at 7-10{sup o}C than at 18{sup o}C. At 7{sup o}C, the biological half time for assimilated {sup 237}Pu was about 28 days, at 10{sup o}C about 15 days and at 18{sup o}C about 8 days. Very little {sup 237}Pu was transported from the gut to the internal tissues (about 1%); most was retained in the hepatopancreas. (author).

  3. Correction to: Kürti, László. “Review Article: Documenting Immigrants, Boarding Houses and Ethnographers. Burdosház Amerikából – Balogh Balázs néprajzkutató nyomában ('A Boarding House from America - in the Footsteps of Ethnographer Balázs Balogh'. Directed by Dezső Zsigmond, produced by Dunatáj Alapítvány, Camera: Arthur Bálint, 2015, 50:39 minutes.” Hungarian Cultural Studies. e-Journal of the American Hungarian Educators Association, Volume 9 (2016 DOI: 10.5195/ahea.2016.237

    Directory of Open Access Journals (Sweden)

    László Kürti

    2017-09-01

    Full Text Available Changing the incorrect word “script” to “scrip”. The word “scrip” refers to the method of payment used in companies instead of legal tender. The original article can be found via the DOI: http://doc.doi.org/10.5195/ahea.2016.237

  4. Radiation protection data sheet. Radiation protection data sheets for the use of radionuclides in unsealed sources

    International Nuclear Information System (INIS)

    Anon.

    1999-01-01

    These radiation protection data sheet are devoted to responsible persons and employees of various laboratories or medical, pharmaceutical, university and industrial departments where radionuclides are handled as well as all the persons who attend to satisfy in this field. They contain the essential radiation protection data for the use of unsealed sources: physical characteristics, risk assessment, administrative procedures, recommendations, regulations and bibliography. This new series includes the following radionuclides: californium 252, curium 244, gallium 67, indium 113m, plutonium 238, plutonium 239, polonium 210, potassium 42, radium 226, thorium 232, uranium 238 and zinc 65. (O.M.)

  5. Determination of the relative power density distribution in a heterogeneous reactor from the results of measurements of the reactivity effects and the neutron importance function

    International Nuclear Information System (INIS)

    Bobrov, A. A.; Glushkov, E. S.; Zimin, A. A.; Kapitonova, A. V.; Kompaniets, G. V.; Nosov, V. I.; Petrushenko, R. P.; Smirnov, O. N.

    2012-01-01

    A method for experimental determination of the relative power density distribution in a heterogeneous reactor based on measurements of fuel reactivity effects and importance of neutrons from a californium source is proposed. The method was perfected on two critical assembly configurations at the NARCISS facility of the Kurchatov Institute, which simulated a small-size heterogeneous nuclear reactor. The neutron importance measurements were performed on subcritical and critical assemblies. It is shown that, along with traditionally used activation methods, the developed method can be applied to experimental studies of special features of the power density distribution in critical assemblies and reactors.

  6. About the first experiment on investigation of 129I, 237Np, 238Pu and 239Pu transmutation at the nuclotron 2.52 GeV deuteron beam in neutron field generated in U/Pb-assembly 'Energy plus transmutation'

    International Nuclear Information System (INIS)

    Krivopustov, M.I.; Pavliouk, A.V.; Malakhov, A.I.

    2008-01-01

    Preliminary results of the first experiment with energy 2.52 GeV at the electronuclear setup which consists of Pb-target (diameter 8.4 cm, length 45.6 cm) and nat U-blanket (206.4 kg), transmutation samples of 129 I, 237 Np, 238 Pu and 239 Pu (radioecological aspect) are described. Hermetically sealed samples in notable amounts are gathered in atomic reactors and setups of industries which use nuclear materials and nuclear technologies were irradiated in the field of neutrons produced in the Pb-target and propagated in the nat U-blanket. Estimates of transmutations were obtained as a result of measurements of gamma activities of the samples. The information about the space and energy distribution of neutrons in the volume of the lead target and the uranium blanket was obtained with the help of sets of activation threshold detectors (Al, Co, Y, I, Au, Bi and others), solid-state nuclear track detectors, 3 He neutron detectors and nuclear emulsion. Comparison of the experimental data with the results of simulation with the MCNPX program was performed

  7. Prevalence, distribution and functional significance of the -237C to T polymorphism in the IL-12Rβ2 promoter in Indian tuberculosis patients.

    Directory of Open Access Journals (Sweden)

    Vikas Kumar Verma

    Full Text Available Cytokine/cytokine receptor gene polymorphisms related to structure/expression could impact immune response. Hence, the -237 polymorphic site in the 5' promoter region of the IL-12Rβ2 (SNP ID: rs11810249 gene associated with the AP-4 transcription motif GAGCTG, was examined. Amplicons encompassing the polymorphism were generated from 46 pulmonary tuberculosis patients, 35 family contacts and 28 miscellaneous volunteers and sequenced. The C allele predominated among patients, (93.4%, 43/46, and in all volunteers and contacts screened, but the T allele was exclusively limited to patients, (6.5%, 3/46. The functional impact of this polymorphism on transcriptional activity was assessed by Luciferase-reporter and electrophoretic mobility shift assays (EMSA. Luciferase-reporter assays showed a significant reduction in transcriptional efficiency with T compared to C allele. The reduction in transcriptional efficiency with the T allele construct (pGIL-12Rb2-T, in U-87MG, THP-1 and Jurkat cell lines, were 53, 37.6, and 49.8% respectively, compared to the C allele construct (pGIL-12Rb2-C. Similarly, densitometric analysis of the EMSA assay showed reduced binding of the AP-4 transcription factor, to T compared to the C nucleotide probe. Reduced mRNA expression in all patients (3/3 harboring the T allele was seen, whereas individuals with the C allele exhibited high mRNA expression (17/25; 68%, p = 0.05. These observations were in agreement with the in vitro assessment of the promoter activity by Luciferase-reporter and EMSA assays. The reduced expression of IL-12Rβ2 transcripts in 8 patients despite having the C allele was attributed to the predominant over expression of the suppressors (IL-4 and GATA-3 and reduced expression of enhancers (IFN-α of IL-12Rβ2 transcripts. The 17 high IL-12Rβ2 mRNA expressers had significantly elevated IFN-α mRNA levels compared to low expressers and volunteers. Notwithstanding the presence of high levels of IL-12R

  8. The fission cross sections of /sup 230/Th, /sup 232/Th, /sup 233/U, /sup 234/U, /sup 236/U, /sup 238/U, /sup 237/Np, /sup 239/Pu and /sup 242/Pu relative /sup 235/U at 14. 74 MeV neutron energy

    Energy Technology Data Exchange (ETDEWEB)

    Meadows, J.W.

    1986-12-01

    The measurement of the fission cross section ratios of nine isotopes relative to /sup 235/U at an average neutron energy of 14.74 MeV is described with particular attention to the determination of corrections and to sources of error. The results are compared to ENDF/B-V and to other measurements of the past decade. The ratio of the neutron induced fission cross section for these isotopes to the fission cross section for /sup 235/U are: /sup 230/Th - 0.290 +- 1.9%; /sup 232/Th - 0.191 +- 1.9%; /sup 233/U - 1.132 +- 0.7%; /sup 234/U - 0.998 +- 1.0%; /sup 236/U - 0.791 +- 1.1%; /sup 238/U - 0.587 +- 1.1%; /sup 237/Np - 1.060 +- 1.4%; /sup 239/Pu - 1.152 +- 1.1%; /sup 242/Pu - 0.967 +- 1.0%. 40 refs., 11 tabs., 9 figs.

  9. Capability to Recover Plutonium-238 in H-Canyon/HB-Line - 13248

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Kenneth S. Jr.; Smith, Robert H. Jr.; Goergen, Charles R. [Savannah River Nuclear Solutions, LLC, Savannah River Site, Aiken, SC 29802 (United States)

    2013-07-01

    Plutonium-238 is used in Radioisotope Thermoelectric Generators (RTGs) to generate electrical power and in Radioisotope Heater Units (RHUs) to produce heat for electronics and environmental control for deep space missions. The domestic supply of Pu-238 consists of scrap material from previous mission production or material purchased from Russia. Currently, the United States has no significant production scale operational capability to produce and separate new Pu-238 from irradiated neptunium-237 targets. The Department of Energy - Nuclear Energy is currently evaluating and developing plans to reconstitute the United States capability to produce Pu-238 from irradiated Np-237 targets. The Savannah River Site had previously produced and/or processed all the Pu-238 utilized in Radioisotope Thermoelectric Generators (RTGs) for deep space missions up to and including the majority of the plutonium for the Cassini Mission. The previous full production cycle capabilities included: Np- 237 target fabrication, target irradiation, target dissolution and Np-237 and Pu-238 separation and purification, conversion of Np-237 and Pu-238 to oxide, scrap recovery, and Pu-238 encapsulation. The capability and equipment still exist and could be revitalized or put back into service to recover and purify Pu-238/Np-237 or broken General Purpose Heat Source (GPHS) pellets utilizing existing process equipment in HB-Line Scrap Recovery, and H-Canyon Frame Waste Recovery processes. The conversion of Np-237 and Pu-238 to oxide can be performed in the existing HB-Line Phase-2 and Phase- 3 Processes. Dissolution of irradiated Np-237 target material, and separation and purification of Np-237 and Pu-238 product streams would be possible at production rates of ∼2 kg/month of Pu-238 if the existing H-Canyon Frames Process spare equipment were re-installed. Previously, the primary H-Canyon Frames equipment was removed to be replaced: however, the replacement project was stopped. The spare equipment

  10. Attenuation of Foot-and-Mouth Disease Virus by Engineered Viral Polymerase Fidelity.

    Science.gov (United States)

    Rai, Devendra K; Diaz-San Segundo, Fayna; Campagnola, Grace; Keith, Anna; Schafer, Elizabeth A; Kloc, Anna; de Los Santos, Teresa; Peersen, Olve; Rieder, Elizabeth

    2017-08-01

    Foot-and-mouth disease virus (FMDV) RNA-dependent RNA polymerase (RdRp) (3D pol ) catalyzes viral RNA synthesis. Its characteristic low fidelity and absence of proofreading activity allow FMDV to rapidly mutate and adapt to dynamic environments. In this study, we used the structure of FMDV 3D pol in combination with previously reported results from similar picornaviral polymerases to design point mutations that would alter replication fidelity. In particular, we targeted Trp237 within conserved polymerase motif A because of the low reversion potential inherent in the single UGG codon. Using biochemical and genetic tools, we show that the replacement of tryptophan 237 with phenylalanine imparts higher fidelity, but replacements with isoleucine and leucine resulted in lower-fidelity phenotypes. Viruses containing these W237 substitutions show in vitro growth kinetics and plaque morphologies similar to those of the wild-type (WT) A 24 Cruzeiro strain in BHK cells, and both high- and low-fidelity variants retained fitness during coinfection with the wild-type virus. The higher-fidelity W237F (W237F HF ) mutant virus was more resistant to the mutagenic nucleoside analogs ribavirin and 5-fluorouracil than the WT virus, whereas the lower-fidelity W237I (W237I LF ) and W237L LF mutant viruses exhibited lower ribavirin resistance. Interestingly, the variant viruses showed heterogeneous and slightly delayed growth kinetics in primary porcine kidney cells, and they were significantly attenuated in mouse infection experiments. These data demonstrate, for a single virus, that either increased or decreased RdRp fidelity attenuates virus growth in animals, which is a desirable feature for the development of safer and genetically more stable vaccine candidates. IMPORTANCE Foot-and-mouth disease (FMD) is the most devastating disease affecting livestock worldwide. Here, using structural and biochemical analyses, we have identified FMDV 3D pol mutations that affect polymerase

  11. Dicty_cDB: Contig-U04716-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ( BV429027 ) S237P6215FG6.T0 PortugueseWaterDog Canis familiar... 38 6e-04 2 ( CE020668 ) tigr-gss-dog-1700...AFT ... 48 0.034 2 ( CE733596 ) tigr-gss-dog-17000315432205 Dog Library Canis lup... 38 0.034 2 ( BV431612 ) S237P656RA1.T0 Portugues...library Mus ... 38 0.13 2 ( BV431707 ) S237P6458FA8.T0 PortugueseWaterDog Canis familiar... 38 0.13 2 ( BV25... ( BV437326 ) S237P6229FG2.T0 PortugueseWaterDog Canis familiar... 38 0.13 2 ( CE358139 ) tigr-gss-dog-17000... Canis lup... 38 0.14 2 ( BV432826 ) S237P6430RB9.T0 PortugueseWaterDog Canis familiar... 36 0.14 2 ( CE4742

  12. Spectrum-averaged cross-section measurement of /sup 103/Rh(n,n)/sup 103m/Rh in the /sup 252/Cf fission neutron spectrum

    International Nuclear Information System (INIS)

    Lamaze, G.P.; Schima, F.J.; Eisenhauer, C.M.; Spiegel, V.

    1988-01-01

    Because of the similarity in energy dependence of the /sup 103/Rh(n,n') differential cross section to the kerma muscle response function for neutrons, rhodium may be useful as a neutron kerma monitor. In support of its use as a neutron monitor, the spectrum-averaged cross section σ-bar has been measured for a /sup 252/Cf fission neutron spectrum. Pairs of thin rhodium samples were irradiated on opposite sides of a thinly encapsulated /sup 252/Cf neutron source. The neutron emission rate of the /sup 252/Cf source was determined by the manganous sulfate (MnSO/sub 4/) bath technique. In this method, the californium source emission rate is determined by comparison to the known emission rate of NBS-I, a standard radium-beryllium neutron source. The neutron fluence incident on the rhodium samples is determined from the californium source strength, average sample-to-source distance, and the duration of the irradiation. Corrections are made for neutron scattering saturation of activity, and attenuation of the X rays by the sample during counting. The X rays were detected with an intrinsic germanium detector designed specifically for low-energy X-ray detection. The activity was not determined by absolute counting so that the final results depend on the value of P/sub Κx/, to total Κ X-ray emission probability. The results of five separate irradiations yield a value of σ-bar . P/sub Κx/ = 62.3 +- 1.9 mb. Using the most recently published value of P/sub Κx/ gives a value of σ-bar = 739 +- 22 mb. A discussion of systematic uncertainties is given

  13. Publications | Page 237 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... the agro-pastoral systems of Tanzania : a gendered analysis (open access) ... This paper deals with the ways in which gender and caste identities marginalise particular groups from access to water in a village in periurban Hyderabad, India.

  14. 33 CFR 117.237 - Christina River.

    Science.gov (United States)

    2010-07-01

    ... five short blasts, and an audio voice warning stating, “Attention, Attention. Norfolk Southern Railroad... infrared detectors, until green lights are displayed on the swing span. (c) The draw of the Third Street...

  15. Publications | Page 237 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... we aim to widen the impact of our investment and advance development research. ... from place to place; this is mainly due to social and economic influences. ... with reference to specific technologies: the computer and the cell phone.

  16. 50 CFR 648.237 - Framework provisions.

    Science.gov (United States)

    2010-10-01

    ... Committee composition and process; description and identification of essential fish habitat; description and identification of habitat areas of particular concern; overfishing definition and related thresholds and targets... measures must come from one or more of the following categories: Minimum fish size; maximum fish size; gear...

  17. Use of californium-252 sources in Hungary for teaching and research

    International Nuclear Information System (INIS)

    Csikai, J.

    1976-01-01

    An activation facility was designed to accommodate up to 50 mg of 252 Cf; it contains at present a 500 μg source. The absolute values of thermal, epithermal and fast neutron fluxes were determined by the foil activation method using In, Dy, Au, Al and Fe detectors. Cross-sections averaged for unmoderated 252 Cf neutrons were determined for 22 different reactions for elements with atomic weights lying between A=27 and 204. The sensitivity for determination of Al, Ti, Cu, As, Sr, Mo, In, Cd, Ba, Au, Hg and Pb was calculated for NaI(Tl) and Ge(Li) detectors. Average (n,2n) cross-sections for 252 Cf spectrum were calculated for 49 nuclei lying between A=14 and 204. Angular distributions and cross-sections for the fragments from 252 Cf neutron-induced fission of 232 Th and 238 U were measured. Titanium in bauxite and manganese in aluminium alloys were determined with a 252 Cf source. The applicability of solid-state track detectors for neutron dosimetry, radiography and for the determination of fuel burn-up were investigated using 252 Cf neutron and fragment sources. Characteristics of a jumping spark counter for counting fission fragments were studied with 252 Cf sources. (author)

  18. Review of microscopic integral cross section data in fundamental reactor dosimetry benchmark neutron fields

    International Nuclear Information System (INIS)

    Fabry, A.; McElroy, W.N.; Kellogg, L.S.; Lippincott, E.P.; Grundl, J.A.; Gilliam, D.M.; Hansen, G.E.

    1976-01-01

    This paper is intended to review and critically discuss microscopic integral cross section measurement and calculation data for fundamental reactor dosimetry benchmark neutron fields. Specifically the review covers the following fundamental benchmarks: the spontaneous californium-252 fission neutron spectrum standard field; the thermal-neutron induced uranium-235 fission neutron spectrum standard field; the (secondary) intermediate-energy standard neutron field at the center of the Mol-ΣΣ, NISUS, and ITN-ΣΣ facilities; the reference neutron field at the center of the Coupled Fast Reactor Measurement Facility; the reference neutron field at the center of the 10% enriched uranium metal, cylindrical, fast critical; the (primary) Intermediate-Energy Standard Neutron Field

  19. Development of a transportable neutron radiography system for non-destructive tests application

    International Nuclear Information System (INIS)

    Silva, Ademir X. da; Crispim, Verginia R.

    1999-01-01

    This paper presents a study of a transportable neutron radiography system utilizing californium-252. Studies about moderation, collimation and shielding are showed. A Monte Carlo Code, MCNP3b, has been used to obtain a maximum and more homogeneous thermal neutron flux in the collimator outlet next to the image plain, and an adequate radiation shielding to attend radiological protection rules. With the presented collimator, it was possible to obtain for the thermal neutron flux, at the collimator outlet and next to the image plain, a L/D ratio 7,5, for neutron flux up to 6 X 10 -6 cm -2 .s -1 per neutron source. (author)

  20. Neutron crosstalk between liquid scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Verbeke, J.M., E-mail: verbeke2@llnl.gov; Prasad, M.K., E-mail: prasad1@llnl.gov; Snyderman, N.J., E-mail: snyderman1@llnl.gov

    2015-09-11

    A method is proposed to quantify the fractions of neutrons scattering between liquid scintillators. Using a spontaneous fission source, this method can be utilized to quickly characterize an array of liquid scintillators in terms of crosstalk. The point model theory due to Feynman is corrected to account for these multiple scatterings. Using spectral information measured by the liquid scintillators, fractions of multiple scattering can be estimated, and mass reconstruction of fissile materials under investigation can be improved. Monte Carlo simulations of mono-energetic neutron sources were performed to estimate neutron crosstalk. A californium source in an array of liquid scintillators was modeled to illustrate the improvement of the mass reconstruction.

  1. Neutron crosstalk between liquid scintillators

    International Nuclear Information System (INIS)

    Verbeke, J.M.; Prasad, M.K.; Snyderman, N.J.

    2015-01-01

    A method is proposed to quantify the fractions of neutrons scattering between liquid scintillators. Using a spontaneous fission source, this method can be utilized to quickly characterize an array of liquid scintillators in terms of crosstalk. The point model theory due to Feynman is corrected to account for these multiple scatterings. Using spectral information measured by the liquid scintillators, fractions of multiple scattering can be estimated, and mass reconstruction of fissile materials under investigation can be improved. Monte Carlo simulations of mono-energetic neutron sources were performed to estimate neutron crosstalk. A californium source in an array of liquid scintillators was modeled to illustrate the improvement of the mass reconstruction

  2. Radiological safety considerations in the design and operation of the ORNL Transuranium Research Laboratory (TRL)

    International Nuclear Information System (INIS)

    Haynes, C.E.

    1976-01-01

    The Transuranium Research Laboratory (TRL) is the central facility at Oak Ridge National Laboratory (ORNL) for chemical and physical research involving transuranium elements. Transuranium Research Laboratory investigations are about equally divided between studies of inorganic and structural chemistry of the heavy elements and nuclear structure and properties of their isotopes. Elements studied include neptunium, plutonium, americium, curium, berkelium, californium, and einsteinium, each in microgram-to-gram quantities depending upon availability and experimental requirements. This paper describes an eight-step safety procedure followed in planning and approving individual research projects. This procedure should provide an optimum margin of safety and should permit the accomplishment of successful research

  3. Determination of alpha activity and fissile mass content in solid waste by systems using neutron interrogation

    International Nuclear Information System (INIS)

    Romeyer Dherbey, J.; Lacruche, G.; Berne, R.; Auge, J.; Martin Deidier, L.; Butez, M.

    1990-01-01

    The Quantitative control (determination of heavy nuclides and alpha activity) of alpha radioactive wastes is necessary, particularly to determine if the waste is in accordance with the surface storage limits. In order to reduce the uncertainty on the alpha activity resulting from unknown isotopic composition, inhomogeneity of heavy nuclides in the matrix, combination of several methods is necessary. In the paper we present the Cadarache development work in the NDA of solid waste using the Californium shuffler, 14 Mev neutron generator, and also passive techniques such as neutron emission measurement and gamma spectrometry. Experimental systems combining active and passive methods are presented (COSAC, BANCO, DANAIDE, PROMETHEE)

  4. Beam test of a grid-less multi-harmonic buncher

    International Nuclear Information System (INIS)

    Ostroumov, P.N.; Aseev, V.N.; Barcikowski, A.; Clifft, B.; Pardo, R.; Sharamentov, S.I.; Sengupta, M.

    2008-01-01

    The Argonne Tandem Linear Accelerator System (ATLAS) is the first superconducting heavy-ion linac in the world. Currently ATLAS is being upgraded with the Californium Rare Ion Breeder Upgrade (CARIBU). The latter is a funded project to expand the range of shortlived, neutron-rich rare isotope beams available for nuclear physics research at ATLAS. To avoid beam losses associated with the existing gridded multi-harmonic buncher (MHB), we have developed and built a grid-less four-harmonic buncher with fundamental frequency of 12.125 MHz. In this paper, we report the results of the MHB commissioning and ATLAS beam performance with the new buncher.

  5. Composition containing transuranic elements for use in the homeopathic treatment of aids

    International Nuclear Information System (INIS)

    Lustig, D.

    1996-01-01

    A homeopathic remedy consisting of a composition containing one or more transuranic elements, particularly plutonium, for preventing and treating acquired immunodeficiency syndrome (AIDS) in humans, as well as seropositivity for human immunodeficiency virus (HIV). Said composition is characterized in that it uses any chemical or isotopic form of one or more transuranic elements (neptunium, plutonium, americium, curium, berkelium, californium or einsteinium), particularly plutonium, said form being diluted and dynamized according to conventional homeopathic methods, particularly the so-called Hahnemann and Korsakov methods, and provided preferably but not exclusively in the form of lactose and/or saccharose globules or granules impregnated with the active principle of said composition. (author)

  6. PROCEEDINGS OF THE SYMPOSIUM COMMEMORATING THE 25th ANNIVERSARY OF ELEMENTS 97 and 98 HELD ON JAN. 20, 1975

    Energy Technology Data Exchange (ETDEWEB)

    Seaborg, Glenn T.; Street Jr., Kenneth; Thompson, Stanley G.; Ghiorso, Albert

    1976-07-01

    This volume includes the talks given on January 20, 1975, at a symposium in Berkeley on the occasion of the celebration of the 25th anniversary of the discovery of berkelium and californium. Talks were given at this symposium by the four people involved in the discovery of these elements and by a number of people who have made significant contributions in the intervening years to the investigation of their nuclear and chemical properties. The papers are being published here, without editing, in the form in which they were submitted by the authors in the months following the anniversary symposium, and they reflect rather faithfully the remarks made on that occasion.

  7. TOWARD AN IMPROVED UNDERSTANDING OF STRUCTURE AND MAGNETISM IN NEPTUNIUM AND PLUTONIUM PHOSPHONATES AND SULFONATES

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht-Schmitt, Thomas

    2012-03-01

    This grant supported the exploratory synthesis of new actinide materials with all of the actinides from thorium to californium with the exceptions of protactinium and berkelium. We developed detailed structure-property relationships that allowed for the identification of novel materials with selective ion-exchange, selective oxidation, and long-range magnetic ordering. We found novel bonding motifs and identified periodic trends across the actinide series. We identified structural building units that would lead to desired structural features and novel topologies. We also characterized many different spectroscopic trends across the actinide series. The grant support the preparation of approximately 1200 new compounds all of which were structurally characterized.

  8. Triton and alpha-particle contribution from LiF converter for neutron dosimeter

    CERN Document Server

    Camacho, M E; Balcazar, M

    1999-01-01

    A personnel neutron dosimeter prototype based on chemical and electrochemical etched CR-39 detector, combined with LiF converter, has been calibrated using an ICRP-like phantom, under a heavy-water moderated Californium source neutron spectra; A conversion factor of 1.052+-126 spots cm sup - sup 2 mSv sup - sup 1 was obtained. The sealing properties of the detector holder showed a ten-fold reduction in radon background when it was tested in a high radon atmosphere. A convenient mechanical shock resistance was achieved in LiF converters by sintering to 11 tons pressure LiF powder at 650 deg. C, during one hour.

  9. Critical Masses for Unreflected Metal Spheres

    International Nuclear Information System (INIS)

    Westfall, Robert Michael; Wright, Richard Q.

    2009-01-01

    Calculated critical masses of bare metal spheres for 28 actinide isotopes, using the SCALE/XSDRNPM one-dimensional, discrete-ordinates system, are presented. ENDF/B-VI, ENDF/B-VII, and JENDL-3.3 cross sections were used in the calculations. Results are given for isotopes of uranium, neptunium, plutonium, americium, curium, californium, and for one isotope of einsteinium. Calculated k values for these same nuclides are also given. We show that, for non-threshold or low-threshold fission nuclides, a good approximation for the nuclide k is the value of nubar at 1 MeV. A plot of the critical mass versus k values is given for 19 nuclides with A-numbers between 232 and 250. The peaks in the critical mass curve (for seven nuclides) correspond to dips in the k curve. For the seven cases with the largest critical mass, six are even-even nuclides. Neptunium-237, with a critical mass of about 62.7 kg (ENDF/B-VI calculation), has an odd number of protons and an even number of neutrons. However, two cases with quite small critical masses, 232U and 236Pu, are also even-even. These two nuclides do not exhibit threshold fission behavior like most other even-even nuclides. The largest critical mass is 208.8 kg for 243Am and the smallest is 2.44 kg for 251Cf. The calculated k values vary from 1.5022 for 234U to 4.4767 for 251Cf. A correlation between the calculated critical mass (kg) and the fission spectrum averaged value of is given for the elements U, Np, Pu, Am, Cm, and Cf. For each of the five elements, a fit to the data for that element is provided. In each case the fit employs a negative exponential of the form mass = exp(A + B ∼ ln). The values of A and B are element dependent and vary slightly for each of the five elements. The method described here is mainly applicable for non-threshold fission nuclides (15 of the 28 nuclides considered in this paper). There are three exceptions, 238Pu, 244Cm, and 250Cf, which all exhibit threshold fission behavior.

  10. Modelling of the radioactive daughter elements in soil to assess radiation impact due to contaminated irrigation water by parents of 231Pa, 226Ra, 238U, 237Np and 239Pu

    International Nuclear Information System (INIS)

    Bela Kanyar; Katalin Eged; Tunde Katona; Gerhard Proehl; Ulla Bergstroem; Bengt Hallberg; Shelly Mobbs; Geert Olyslaegers; Theo Zeevaert; Palome Pinedo; Inmaculade Simon

    2004-01-01

    Radioactive wastes may contain both parent and daughter radionuclides. In some cases the transfer parameters of the daughter radio-elements differ significantly from that of the parent ones and therefore the dose contributions in the different pathways might be important to assess separately. The present work has compared 5 different site specific models by a scenario, using contaminated water for drinking and irrigation. Altogether 5 radionuclides from the investigated 10 ones contained radioactive daughter elements. In general, for long term studies in biosphere the steady-state formulations of processes are adequate to assess the contamination, except the infiltration into the deeper soil and sediment layers. According to the results of the modelling and computer simulations, the following daughters are to be assessed separately from their parents with respect to the radiation impact: for parent 231 Pa the daughter 227 Ac, for parent 226 Ra the daughters 222 Rn, 210 Pb and 210 Po and for parent 237 Np the daughter 233 Pa. The dose contributions of the daughters from parents 238 U and 239 Pu are less significant during the considered 100-10000 years. In case of contamination of irrigation water with 1 Bq x m -3 of the parent radionuclide 231 Pa, more than 90% of the external dose from soil exposure comes from the daughter 227 Ac (annually 15 nSv). By a similar contamination with 226 Ra as a parent radionuclide, 60% of the ingestion dose is due to food contamination with the daughters 210 Pb and 210 Po (approximately 150 nSv x a -1 ). (author)

  11. Study of reproducibility of measurements with the spectrometer of Bonner multispheres

    International Nuclear Information System (INIS)

    Azevedo, G.A.; Pereira, W.W.; Patrao, K.C.S.; Fonseca, E.S.

    2013-01-01

    This work aims to study the metrological behavior of the Bonner Multisphere Spectrometer (BMS) of the LN / LNMRI / IRD - Laboratorio Metrologia de Neutrons / Laboratorio Nacional de Metrologia e Radiacao Ionizante / Instituto de Radioprotecao e Dosimetria, for measurements in repeatability and reproducibility conditions. Initially, a simulation was done by applying the Monte Carlo method, using the MCNP code and respecting the ISO 8529-1 (2001), using the sources of Californium ( 252 Cf), Americium-Beryllium ( 241 AmBe) and californium in heavy water (Cf + D 2 O), all located at a distance of 100 cm from the neutron detector ( 6 Li (Eu) - crystal scintillator). In this program, the counting of neutrons that are captured by the detector was made. The source is located in the center of a sphere of radius 300 cm. Analyzes the impact of these neutrons in a point of the sphere wall, which in this case acted as a neutron detector and from there, it is estimated the number of neutrons that collide in the whole sphere. The purpose is to obtain the neutron count for different energy bands in a solid field of neutrons, since they have a spectrum ranging from a low to a high energy that can also vary within a particular environment. Wishes to obtain new fields with different sources and moderators materials to be used as new reference fields. Measurements are being conducted for these fields, with the aim of analyzing the variability conditions of the measurement (repeatability and reproducibility) in LEN - Laboratorio de Espectrometria de Neutrons of the LN/LMNRI/IRD. Thus, the spectrometer will be used to improve both the knowledge of the spectrum as the standard of neutrons of the lab, proving that a spectrometry is essential for correct measurement

  12. Environmental assessment of the thermal neutron activation explosive detection system for concourse use at US airports

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.G.

    1990-08-01

    This document is an environmental assessment of a system designed to detect the presence of explosives in checked airline baggage or cargo. The system is meant to be installed at the concourse or lobby ticketing areas of US commercial airports and uses a sealed radioactive source of californium-252 to irradiate baggage items. The major impact of the use of this system arises from direct exposure of the public to scattered or leakage radiation from the source and to induced radioactivity in baggage items. Under normal operation and the most likely accident scenarios, the environmental impacts that would be created by the proposed licensing action would not be significant. 44 refs., 19 figs., 18 tabs.

  13. Alternative irradiation system for efficiency manganese bath determination

    Energy Technology Data Exchange (ETDEWEB)

    Passos Leite, Sandro, E-mail: sandro@ird.gov.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Wagner Pereira, Walsan, E-mail: walsan@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil); Xavier da Silva, Ademir, E-mail: ademir@con.ufrj.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Simoes da Fonseca, Evaldo, E-mail: evaldo@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil); Souza Patrao, Karla Cristina de, E-mail: karla@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil)

    2010-12-15

    An alternative irradiation system, which works with a radionuclide neutron source and manganese sulphate solution volume have been proposed for efficiency determination of a Manganese Bath System (MBS). This irradiation system was designed by simulation with MCNP5 code, considering a californium neutron source in several manganese sulphate volumes and different neutron reflectors. Although its solution specific activity are less than those in nuclear reactors, the simulation results have showed that the irradiation system proposed takes a manganese neutron capture increase up to 200 times when it compared to manganese neutron capture from a MBS whose diameter is about 100 cm. That becomes possible to use those samples for some of the absolute specific activity measuring methods.

  14. Experimental survey of the potential energy surfaces associated with fission

    International Nuclear Information System (INIS)

    Britt, H.C.

    1980-01-01

    Progress in the experimental determination of the properties of the potential energy surface associated with fission is reviewed. The importance of nuclear symmetry effects on the calculation of fission widths is demonstrated. Evidence is presented for the fragmentation of the mass-asymmetric second barrier in the thorium region and the axial asymmetric first barrier in the californium region. Detailed analyses of experimental data suggest the presence of two parallel second barriers; the normal mass-asymmetric, axial-symmetric barrier and a slightly higher mass-symmetric, axial-asymmetric barrier. Experimental barrier parameters are determined systematically and compared with calculations from various theoretical models. Techniques for expanding fission probability measurements to higher energies are discussed. (author)

  15. Environmental assessment of the thermal neutron activation explosive detection system for concourse use at US airports

    International Nuclear Information System (INIS)

    Jones, C.G.

    1990-08-01

    This document is an environmental assessment of a system designed to detect the presence of explosives in checked airline baggage or cargo. The system is meant to be installed at the concourse or lobby ticketing areas of US commercial airports and uses a sealed radioactive source of californium-252 to irradiate baggage items. The major impact of the use of this system arises from direct exposure of the public to scattered or leakage radiation from the source and to induced radioactivity in baggage items. Under normal operation and the most likely accident scenarios, the environmental impacts that would be created by the proposed licensing action would not be significant. 44 refs., 19 figs., 18 tabs

  16. Review of microscopic integral cross section data in fundamental reactor dosimetry benchmark neutron fields

    International Nuclear Information System (INIS)

    Fabry, A.; McElroy, W.N.; Kellogg, L.S.; Lippincott, E.P.; Grundl, J.A.; Gilliam, D.M.; Hansen, G.E.

    1976-10-01

    The paper is intended to review and critically discuss microscopic integral cross section measurement and calculation data for fundamental reactor dosimetry benchmark neutron fields. Specifically the review covers the following fundamental benchmarks: (1) the spontaneous californium-252 fission neutron spectrum standard field; (2) the thermal-neutron induced uranium-235 fission neutron spectrum standard field; (3) the (secondary) intermediate-energy standard neutron field at the center of the Mol-ΣΣ, NISUS, and ITN--ΣΣ facilities; (4) the reference neutron field at the center of the Coupled Fast Reactor Measurement Facility (CFRMF); (5) the reference neutron field at the center of the 10 percent enriched uranium metal, cylindrical, fast critical; and (6) the (primary) Intermediate-Energy Standard Neutron Field

  17. Construction of a Recyclable Genetic Marker and Serial Gene Deletions in the Human Pathogenic Mucorales Mucor circinelloides.

    Science.gov (United States)

    Garcia, Alexis; Adedoyin, Gloria; Heitman, Joseph; Lee, Soo Chan

    2017-07-05

    Mucor circinelloides is a human pathogen, biofuel producer, and model system that belongs to a basal fungal lineage; however, the genetics of this fungus are limited. In contrast to ascomycetes and basidiomycetes, basal fungal lineages have been understudied. This may be caused by a lack of attention given to these fungi, as well as limited tools for genetic analysis. Nonetheless, the importance of these fungi as pathogens and model systems has increased. M. circinelloides is one of a few genetically tractable organisms in the basal fungi, but it is far from a robust genetic system when compared to model fungi in the subkingdom Dikarya. One problem is the organism is resistant to drugs utilized to select for dominant markers in other fungal transformation systems. Thus, we developed a blaster recyclable marker system by using the pyrG gene (encoding an orotidine-5'-phosphate decarboxylase, ortholog of URA3 in Saccharomyces cerevisiae ). A 237-bp fragment downstream of the pyrG gene was tandemly incorporated into the upstream region of the gene, resulting in construction of a pyrG-dpl237 marker. To test the functionality of the pyrG-dpl237 marker, we disrupted the carRP gene that is involved in carotenoid synthesis in pyrG - mutant background. The resulting carRP :: pyrG-dpl237 mutants exhibit a white colony phenotype due to lack of carotene, whereas wild type displays yellowish colonies. The pyrG marker was then successfully excised, generating carRP-dpl237 on 5-FOA medium. The mutants became auxotrophic and required uridine for growth. We then disrupted the calcineurin B regulatory subunit cnbR gene in the carRP :: dpl237 strain, generating mutants with the alleles carRP :: dpl237 and cnbR :: pyrG These results demonstrate that the recyclable marker system is fully functional, and therefore the pyrG-dpl237 marker can be used for sequential gene deletions in M. circinelloides . Copyright © 2017 Garcia et al.

  18. Construction of a Recyclable Genetic Marker and Serial Gene Deletions in the Human Pathogenic Mucorales Mucor circinelloides

    Directory of Open Access Journals (Sweden)

    Alexis Garcia

    2017-07-01

    Full Text Available Mucor circinelloides is a human pathogen, biofuel producer, and model system that belongs to a basal fungal lineage; however, the genetics of this fungus are limited. In contrast to ascomycetes and basidiomycetes, basal fungal lineages have been understudied. This may be caused by a lack of attention given to these fungi, as well as limited tools for genetic analysis. Nonetheless, the importance of these fungi as pathogens and model systems has increased. M. circinelloides is one of a few genetically tractable organisms in the basal fungi, but it is far from a robust genetic system when compared to model fungi in the subkingdom Dikarya. One problem is the organism is resistant to drugs utilized to select for dominant markers in other fungal transformation systems. Thus, we developed a blaster recyclable marker system by using the pyrG gene (encoding an orotidine-5′-phosphate decarboxylase, ortholog of URA3 in Saccharomyces cerevisiae. A 237-bp fragment downstream of the pyrG gene was tandemly incorporated into the upstream region of the gene, resulting in construction of a pyrG-dpl237 marker. To test the functionality of the pyrG-dpl237 marker, we disrupted the carRP gene that is involved in carotenoid synthesis in pyrG− mutant background. The resulting carRP::pyrG-dpl237 mutants exhibit a white colony phenotype due to lack of carotene, whereas wild type displays yellowish colonies. The pyrG marker was then successfully excised, generating carRP-dpl237 on 5-FOA medium. The mutants became auxotrophic and required uridine for growth. We then disrupted the calcineurin B regulatory subunit cnbR gene in the carRP::dpl237 strain, generating mutants with the alleles carRP::dpl237 and cnbR::pyrG. These results demonstrate that the recyclable marker system is fully functional, and therefore the pyrG-dpl237 marker can be used for sequential gene deletions in M. circinelloides.

  19. Californium-252 neutron activation analysis of high-level processed nuclear tank waste

    International Nuclear Information System (INIS)

    Troyer, G.L.; Purcell, M.A.

    2000-01-01

    The basis for production assessment of the vitrification of Hanford nuclear fuel reprocessing wastes will be high-precision measurements of the elemental sodium content. However, the chemical analysis of both radioactive and nonradioactive components in nuclear waste can be challenged by high radiation dose rates. The dose rates compromise many analytical techniques as well as pose personnel dosimetry risks. In many cases, reduction of dose rates through dilution compromises the precision and sensitivity for certain key components. The use of neutron activation analysis (NAA) provides a method of analysis that avoids the need for dilutions or extensive sample preparation. These waste materials also contain trace quantities of fissionable isotopes, which, through neutron activation, can be estimated by delayed neutron counting of fissioned fragments

  20. Californium-252: isotope for modern radiotherapy of cervix, uterine and vaginal carcinomas

    International Nuclear Information System (INIS)

    Maruyama, J.; Beach, J.L.; Nagell, J.R. van

    1984-01-01

    Cf-252 is an isotope that can easily be afterloaded into available gynecological applicators and used for bulky cervix, uterus or vaginal cancer therapy. It is economical, time and cost effective in use, and can be applied to the therapy of many patients throughout the world. It is more effective for neutron therapy than machine fast neutron therapy and is the only form of neutron therapy producing consistent complication-free 5-year cure of advanced cancers currently available. Cf-252 is an isotope for modern gynecological tumor therapy for the future. Isodose curves for Cf-252 implants revealed dose distributions conforming well to tumor. (orig.) [de

  1. 48 CFR 252.237-7016 - Delivery tickets.

    Science.gov (United States)

    2010-10-01

    ...), and (e) to the basic clause: (c) Before the Contractor picks up articles for service under this... of serviced laundry on the delivery ticket. The Contracting Officer will ensure that this weight and... articles for service under this contract, the Contracting Officer will ensure that each bag is weighed and...

  2. 48 CFR 252.237-7017 - Individual laundry.

    Science.gov (United States)

    2010-10-01

    ... clause: Individual Laundry (DEC 1991) (a) The Contractor shall provide laundry service under this... services. (c) Charges for individual laundry will be on a per unit bundle or a piece-rate basis. The... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Individual laundry. 252...

  3. 237 MORAL AND PSYCHOLOGICAL FILICIDE: EXAMINING THE ...

    African Journals Online (AJOL)

    Fr. Ikenga

    no good hospital, employment opportunity or social infrastructure and where poverty level is over. 300%, how will you expect a family to reject the gains from anti-social ..... Likewise, every child has the right to maintenance by his parents or guardians in accordance with the extent of their means, and the child has the right, ...

  4. 237 MORAL AND PSYCHOLOGICAL FILICIDE: EXAMINING THE ...

    African Journals Online (AJOL)

    Fr. Ikenga

    Nigerian campuses of higher learning or the like that engage in sex for .... children and causing various risks to the child safety… ... their babies with them for up to 18months gives room for bonding of mother and child, .... be likely to adversely affect his physical, mental, spiritual, moral or social development or employed as.

  5. 7 CFR 2.37 - Chief Information Officer.

    Science.gov (United States)

    2010-01-01

    ... acquisition; (iii) Approve the appointment of the program manager for each major information technology... recommendations to Agency Heads for the removal or replacement of information technology project managers, when... regarding information technology matters. (2) Overseeing all information technology and information resource...

  6. 48 CFR 1552.237-71 - Technical direction.

    Science.gov (United States)

    2010-10-01

    .... (d) Technical direction will be issued in writing or confirmed in writing within five (5) days after... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Technical direction. 1552... Technical direction. As prescribed in 1537.110, insert a clause substantially the same as the following...

  7. 48 CFR 237.104 - Personal services contracts.

    Science.gov (United States)

    2010-10-01

    ... intelligence component or counter-intelligence organization of DoD; or (iii) Directly support the mission of... travel between home or place of business and official duty station. (iii) Coordinate with the civilian... SYSTEM, DEPARTMENT OF DEFENSE SPECIAL CATEGORIES OF CONTRACTING SERVICE CONTRACTING Service Contracts...

  8. Neptunium Transport Behavior in the Vicinity of Underground Nuclear Tests at the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, P; Tinnacher, R M; Zavarin, M; Williams, R W; Kersting, A B

    2010-12-03

    We used short lived {sup 239}Np as a yield tracer and state of the art magnetic sector ICP-MS to measure ultra low levels of {sup 237}Np in a number of 'hot wells' at the Nevada National Security Site (NNSS), formerly known as the Nevada Test Site (NTS). The results indicate that {sup 237}Np concentrations at the Almendro, Cambric, Dalhart, Cheshire and Chancellor sites, are in the range of 3 x 10{sup -5} to 7 x 10{sup -2} pCi/L and well below the MCL for alpha emitting radionuclides (15 pCi/L) (EPA, 2009). Thus, while Np transport is believed to occur at the NNSS, activities are expected to be well below the regulatory limits for alpha-emitting radionuclides. We also compared {sup 237}Np concentration data to other radionuclides, including tritium, {sup 14}C, {sup 36}Cl, {sup 99}Tc, {sup 129}I, and plutonium, to evaluate the relative {sup 237}Np transport behavior. Based on isotope ratios relative to published unclassified Radiologic Source Terms (Bowen et al., 1999) and taking into consideration radionuclide distribution between melt glass, rubble and groundwater (IAEA, 1998), {sup 237}Np appears to be substantially less mobile than tritium and other non-sorbing radionuclides, as expected. However, this analysis also suggests that {sup 237}Np mobility is surprisingly similar to that of plutonium. The similar transport behavior of Np and Pu can be explained by one of two possibilities: (1) Np(IV) and Pu(IV) oxidation states dominate under mildly reducing NNSS groundwater conditions resulting in similar transport behavior or (2) apparent Np transport is the result of transport of its parent {sup 241}Pu and {sup 241}Am isotopes and subsequent decay to {sup 237}Np. Finally, measured {sup 237}Np concentrations were compared to recent Hydrologic Source Term (HST) models. The 237Np data collected from three wells in Frenchman Flat (RNM-1, RNM-2S, and UE-5n) are in good agreement with recent HST transport model predictions (Carle et al., 2005). The agreement

  9. New equations to calculate temperature correction factors for PO2 in human blood.

    Science.gov (United States)

    Inaba, H; Ohwada, T; Sato, J; Mizuguchi, T; Hirasawa, H

    1986-01-01

    Effects of hemoglobin concentration (Hb), pH, and body temperature (T) on the relationships between delta log PO2/delta T and PO2 were studied by means of a mathematical model using a Newton-Raphson iteration method. The functions between delta log PO2/delta T and PO2 were affected by the above three factors. New equations considering the effects of Hb, pH, and T were proposed by modifying the equation reported by Severinghaus: delta log PO2/delta T = (L +(U-L)/(A(vPO237)B + 1))(10(-2) where U = 3.15-0.45(7.4-pH37) L = 0.68-0.09(7.4-pH37) A = 5.86(exp10(0.074(T)-0.294(7.4-pH37)-11))((Hb)0.913) B = 6.33(exp10(-0.0051(T)))((Hb)-0.113) + 0.24(7.4-pH37) and vPO237 is virtual PO237 which may exist when PO237 is corrected to standard conditions (pH = 7.4, BE = 0) by the following equations: vPO237 = PO237(exp10(fB(7.4-pH37)-0.0013(BE))) fB = (PO237/26.6)0.08-1.52 where fB is the Bohr factor. The above equations provided values of delta log PO2/delta T which fit closely to those obtained by the complex iteration method with maximum differences of less than 1.3 X 10(-3) at T = 27, indicating that maximum % errors for PO2 at T (PO2T) are less than 3.0% at T = 27 and that our equations can be applied over a wide range of Hb, pH37 and T.

  10. A new type-B cask design for transporting 252Cf

    International Nuclear Information System (INIS)

    Simmons, C.M.

    2000-01-01

    A project to design, certify, and build a new US Department of Energy (DOE) Type B container for transporting >5 mg of 252 Cf is more than halfway to completion. This project was necessitated by the fact that the existing Oak Ridge National Laboratory (ORNL) Type B containers were designed and built many years ago and thus do not have the records and supporting data that current regulations require. Once the new cask is available, it will replace the existing Type B containers. The cask design is driven by the unique properties of 252 Cf, which is a very intense spontaneous fission neutron source and necessitates a large amount of neutron shielding. The cask is designed to contain up to 60 mg of 252 Cf in the form of californium oxide or californium oxysulfate, in pellet, wire, or sintered material forms that are sealed inside small special-form capsules. The new cask will be capable of all modes of transport (land, sea, and air). The ORNL team, composed of technical and purchasing personnel and using rigorous selection criteria, chose NAC, International (NAC), as the subcontractor for the project. In January 1997, NAC started work on developing the conceptual design and performing the analyses. The original design concept was for a tungsten alloy gamma shield surrounded by two concentric shells of NS-4-FR neutron shield material. A visit to US Nuclear Regulatory Commission (NRC) regulators in November 1997 to present the conceptual design for their comments resulted in a design modification when the question of potential straight-line cracking in the NS-4-FR neutron shield material arose. NAC's modified design includes offset, wedgelike segments of the neutron shield material. The new geometry eliminates concerns about straight-line cracking but increases the weight of the packaging and makes the fabrication more complex. NAC has now completed the cask design and performed the analyses (shielding, structural, thermal, etc.) necessary to certify the cask. The cask

  11. Quantum helimagnetism of the frustrated spin-1/2 chain LiCuVO.sub.4./sub..

    Czech Academy of Sciences Publication Activity Database

    Enderle, M.; Mukherjee, C.; Fak, B.; Kremer, R. K.; Broto, J.-M.; Rosner, H.; Drechsler, S.-L.; Richter, J.; Málek, Jiří; Prokofiev, A.; Assmus, W.; Pujol, S.; Raggazzoni, J.-L.; Rakato, H.; Rheinstädter, M.; Ronnow, H.M.

    2005-01-01

    Roč. 70, č. 2 (2005), s. 237-243 ISSN 0295-5075 Institutional research plan: CEZ:AV0Z10100520 Keywords : inelastic neutron scattering * magnetic quantum helix Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.237, year: 2005

  12. Physical-chemical studies of transuranium elements: Progress report for the period April 1, 1985-March 31, 1988

    International Nuclear Information System (INIS)

    Peterson, J.R.

    1987-01-01

    New knowledge is being accumulated in the role of the 5f electrons in the bonding in actinide elements and compounds, the relationships of metallic structures to metallic valence and radius, the extent and magnitude of the actinide contraction, the magnetic, thermodynamic, spectroscopic, and crystallographic properties of these materials as related to general theories, the effect of self-irradiation on chemical and physical properties, the chemical and physical consequences of radioactive decay in the bulk-phase solid state, and in general, the range of validity of the actinide hypothesis. Separate reports are given on: spectrophotometric studies of Cf(III) ions in lanthanide trihalide hosts, new ternary transplutonium chalcogenide halides, Raman spectrometric studies of lanthanide trihalides as function of T or P, and solution calorimetry of californium halides

  13. Radionuclide toxicity

    International Nuclear Information System (INIS)

    Galle, P.

    1982-01-01

    The aim of this symposium was to review the radionuclide toxicity problems. Five topics were discussed: (1) natural and artificial radionuclides (origin, presence or emission in the environment, human irradiation); (2) environmental behaviour of radionuclides and transfer to man; (3) metabolism and toxicity of radionuclides (radioiodine, strontium, rare gas released from nuclear power plants, ruthenium-activation metals, rare earths, tritium, carbon 14, plutonium, americium, curium and einsteinium, neptunium, californium, uranium) cancerogenous effects of radon 222 and of its danghter products; (4) comparison of the hazards of various types of energy; (5) human epidemiology of radionuclide toxicity (bone cancer induction by radium, lung cancer induction by radon daughter products, liver cancer and leukaemia following the use of Thorotrast, thyroid cancer; other site of cancer induction by radionuclides) [fr

  14. Fabrication of 50-mg 252Cf neutron sources for the FDA [Food and Drug Administration] activation analysis facility

    International Nuclear Information System (INIS)

    Bigelow, J.E.; Cagle, E.B.; Knauer, J.B.

    1987-01-01

    The Transuranium Processing Plant (TPP) at ORNL has been requested by the Food and Drug Administration (FDA) to furnish 200 mg of 252 Cf for use in their new activation analysis facility. This paper discusses the procedure to be employed in fabricating the californium into four neutron sources, each containing a nominal 50-mg of 252 Cf. The ORNL Model LSD (Large, Stainless steel, Doubly encapsulated) neutron source consists of a 6.33-mm-diam aluminum pellet doubly encapsulated in Type 304L stainless steel. The pellet is comprised of an aluminum tube holding Cf 2 O 2 SO 4 microspheres confined by pressed aluminum powder. The microspheres are prepared in a separate vessel and then transferred into the specially designed aluminum tube prior to pressing

  15. Holdup Measures on an SRNL Mossbauer Spectroscopy Instrument

    Energy Technology Data Exchange (ETDEWEB)

    Dewberry, R.; Brown, T.; Salaymeh, S.

    2010-05-05

    Gamma-ray holdup measurements of a Mossbauer spectroscopy instrument are described and modeled. In the qualitative acquisitions obtained in a low background area of Savannah River National Laboratory, only Am-241 and Np-237 activity were observed. The Am-241 was known to be the instrumental activation source, while the Np-237 is clearly observed as a source of contamination internal to the instrument. The two sources of activity are modeled separately in two acquisition configurations using two separate modeling tools. The results agree well, demonstrating a content of (1980 {+-} 150) {mu}Ci Am-241 and (110 {+-} 50) {mu}Ci of Np-237.

  16. Comparison of fission and capture cross sections of minor actinides

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo; Iwamoto, Osamu

    2003-01-01

    The fission and capture cross sections of minor actinides given in JENDL-3.3 are compared with other evaluated data and experimental data. The comparison was made for 32 nuclides of Th-227, 228, 229, 230, 233, 234, Pa-231, 232, 233, U-232, 234, 236, 237, Np-236, 237, 238, Pu-236, 237, 238, 242, 244, Am-241, 242, 242m, 243, Cm-242, 243, 244, 245, 246, 247 and 248. Given in the present report are figures of these cross sections and tables of cross sections at 0.0253 eV and resonance integrals. (author)

  17. Update neutron nuclear data evaluation for 236,238Np

    International Nuclear Information System (INIS)

    Chen, Guochang; Wang, Jimin; Yu, Baosheng; Cao, Wentian; Tang, Guo-you

    2015-01-01

    The nuclear data with high accuracy for actinides play an important role in nuclear technology applications, including reactor design and operation, fuel cycle, estimation of the amount of minor actinides (MAs) in high burnup reactors and to research to transmute the MAs to short half-lived nuclides or stable ones. The nuclides of 236 Np are generated via the α-decay of 240 Am or 237 Np(n, 2n) and 237 Np(d, t) reactions. And the nuclides of 238 Np are generated via the α-decay of 242 Am or 237 Np(n, γ) and 237 Np(d, p) reactions. In the present work, according to the systematic trend of the total cross section and elastic cross section etc. of different Np isotopes, and based on the neutron optical model parameters (OMP) of 237 Np, a new set of neutron optical model parameters were obtained for 236,238 Np. Based on the new set OMP and the systematic trend of the cross sections of different Np isotopes, a full set of 236,238 Np neutron nuclear data has been updated and improved by theoretical calculation. The present result has significant improvements over the data in CENDL-3.1

  18. Uptake of three isotopes of plutonium from soil by sweet corn grown in a growth chamber

    International Nuclear Information System (INIS)

    Hersloff, L.W.; Corey, J.C.

    1978-01-01

    The use of 237 Pu as a tracer for 238 Pu and 239 Pu was studied in a plant--soil system. Sandy clay--loam soil was spiked with approx. 240 pCi/g of 237 Pu, 14.3 pCi/g of 238 Pu, and 33 pCi/g of 239 Pu in the form of Pu(NO 3 ) 4 . The uptake of these three isotopes of plutonium was measured in the standing vegetation of sweet corn (Zea mays L. var. Silver Queen) after 30 and 50 days of growth. The mean concentrations in the standing crop and the concentration ratios of each isotope decreased from 30 to 50 days. There was an apparent differential availability of the three isotopes: 237 Pu was more available than 238 Pu, which was more available than 239 Pu. The quantity of 237 Pu in the standing crop, on a mass basis, closely approximated that of 238 Pu for both sampling times. Factors influencing these results are discussed

  19. EFFECT OF HYDROPHOBIC ORGANIC POLLUTANTS BIOAVAILABILITY ON ECOTOXICITY OF HISTORICALLY CONTAMINATED SOILS

    Czech Academy of Sciences Publication Activity Database

    Čvančarová, Monika; Innemanová, P.; Cajthaml, Tomáš

    2012-01-01

    Roč. 11, č. 3 (2012), s. 237-237 ISSN 1843-3707. [Environmental Microbiology and Biotechnology. 10.04.2012-12.04.2012, Bologna] R&D Projects: GA TA ČR TA01020804 Institutional research plan: CEZ:AV0Z50200510 Keywords : Supercritical fluid extraction Subject RIV: EE - Microbiology, Virology

  20. Determination of the average number of neutrons per fission event for californium-252

    International Nuclear Information System (INIS)

    Aleksandrov, B.M.; Belov, L.M.; Drapchinskij, L.V.

    1982-01-01

    By means of a separate determination of neutron yields and fission event rates, the value of #betta#-bar( 252 Cf) has been measured for a series of new high-purity sources. The improved quality of the source active layers has reduced the error in determining the fission rate to 0.35%. The value obtained for #betta#-bar( 252 Cf) is 3.747+-0.036. A description is given of the design and the parameters of a spherical manganese bath in which the work on refining the value of #betta#-bar( 252 Cf) will be continued. (author)

  1. Chromatographic cation exchange separation of decigram quantities of californium and other transplutonium elements

    Energy Technology Data Exchange (ETDEWEB)

    Benker, D.E.; Chattin, F.R.; Collins, E.D.; Knauer, J.B.; Orr, P.B.; Ross, R.G.; Wiggins, J.T.

    1980-01-01

    Decigram quantities of highly radioactive transplutonium elements are routinely partitioned at TRU by chromatographic elution from cation resin using AHIB eluent. By using two high-pressure ion exchange columns, a small one for the initial loading of the feed and a large one for the elution, batch runs containing up to 200 mg of /sup 252/Cf can be made in about 5 hours (2 hours to load the feed and 3 hours for the elution). The number of effluent product fractions and the amount of actinides that must be collected in intermediate fractions are minimized by monitoring response from a flow-through alpha-detector. This process has been reliable and relatively easy to operate, and will continue to be used for partitioning transplutonium elements at TRU.

  2. Mutual emergency assistance for radiation accidents

    International Nuclear Information System (INIS)

    1983-03-01

    A revised document on ''Mutual Emergency Assistance for Radiation Accidents'' jointly prepared by the Agency with the participation of the World Health Organization (WHO), the Food and Agricultural Organization of the United Nations (FAO), the International Labour Organisation (ILO) and the Office of the United Nations Disaster Relief Co-ordinator (UNDRO) was issued in 1980 as TECDOC-237. The present document lists the additional information received after publication of the 1980 edition and is issued as a Supplement to TECDOC-237 (1980 Edition). Some useful information contained in TECDOC-237 such as the IAEA arrangement and the WHO Collaborating Centres for Radiation Emergency Assistance are reprinted for ready reference

  3. Browse Title Index

    African Journals Online (AJOL)

    Items 201 - 237 of 237 ... Vol 59 (2015), The IFAA Sunday Forum: Youth Dialogue on the TRC - Reflections and Possibilities, Abstract. CA Lester. Vol 58 (2015), The IMF's advice on fiscal policy, Abstract. A Schimmelpfennig. Vol 67, No 1 (2017), The national health insurance and traditional healing in South Africa, Abstract.

  4. Transuranium Processing Plant semiannual report of production, status, and plans for period ending June 30, 1975

    International Nuclear Information System (INIS)

    King, L.J.; Bigelow, J.E.; Collins, E.D.

    1976-03-01

    During the period January 1, 1975, through June 30, 1975, the following amounts of transuranium elements were recovered from 22 irradiated HFIR targets: 2g 243 Am, 59 g 244 Cm, 51 mg 249 Bk, 465 mg 252 Cf, 2.5 mg 253 Es, and 1.4 pg 257 Fm. In addition, 45 mg of high-purity 248 Cm was operated from 252 Cf which had been recovered and purified during earlier periods, and 56 mg of a lower-quality 248 Cm was separated from californium purification rework solutions. Five HFIR targets, each containing approximately 9 g of actinides (predominantly curium), were fabricated. A new long-term projection showed that 252 Cf production in the TRU-HFIR complex could increase to as much as 2.5 g/year. During the next 18 months, we expect to recover totals of 46 mg of 249 Bk, 520 mg of 252 Cf, 2.0 mg of 253 Es (in a mixture of isotopes), 220 μg of high-purity 253 Es, and 1.6 pg of 257 Fm. We also expect to obtain 125 mg of high-purity 248 Cm from purified californium now in storage. There are no plans to process any of the remaining SRP Pu-Al tubes or to irradiate any plutonium targets in the HFIR; thus, we do not expect to recover any 244 Pu. Two neutron sources were fabricated, bringing the total fabricated to 77. Two sources that had been used previously in various projects were returned to the TRU inventory and are available for reassignment. In special projects, we (1) produced about 1 mg of 250 Cf by irradiation of 249 Bk in HFIR rabbits, and (2) processed some irradiated 248 Cm samples and obtained yield and isotopic composition data for use in determining the capture cross section of 249 Cm in the HFIR. The values that are currently being used for transuranium element decay data and for cross-section data in planning irradiation-processing cycles, calculating production forecasts, and assaying products are tabulated in the Appendix

  5. Dicty_cDB: Contig-U12507-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 129S1/SvImJ Mus musculus STS genomi... 58 0.001 1 ( BV434071 ) S237P6227RB12.T0 PortugueseWaterDog Canis fam...ilia... 58 0.001 1 ( BV424860 ) S237P6196FC6.T0 PortugueseWaterDog Canis familiar

  6. The study of prompt and delayed muon induced fission III. The ratios of prompt to delayed fission yields

    NARCIS (Netherlands)

    Rösel, Ch.; Hänscheid, H.; Hartfiel, J.; Mutius, von R.; Achard van Enschut, d' J.F.M.; David, P; Janszen, H.; Johansson, T.; Konijn, J.; Krogulski, T.; Laat, de C.T.A.M.; Paganetti, H.; Petitjean, C.; Polikanov, S.M.; Reist, H.W.; Risse, F.; Schaller, L.A.; Schrieder, W.; Sinha, A.K.; Taal, A.; Theobald, J.P.; Tibell, G.; Trautmann, N.

    1993-01-01

    The ratios of prompt to delayed fission yields for the isotopes U-233, U-234, U-235, U-236, U-238, Np-237, Pu-242, and Pu-244 and the fission probabilities relative to each other have been investigated experimentally. Using the value of the total fission probability for Np-237 the absolute

  7. Decay Curves and Half-Lives of Gamma-Emitting States from a Study of Prompt Fission Gamma Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Albinsson, H [Chalmers Univ. of Technology, Goeteborg (SE)

    1971-04-15

    Measurements were made on the time distributions of the prompt gamma radiation emitted from fragments in the thermal-neutron induced fission of 235U. The gamma radiation emitted during different time intervals after the fission event was studied with the help of a collimator, the position of which was changed along the path of the fragments. In this way decay curves were obtained from which half-lives could be estimated. Time components with half-lives of 7.5, 18 and 60 ps were found and their relative intensities were calculated. Half-lives and associated intensities are in good agreement with earlier data from uranium and californium fission. Problems involved in this type of study are discussed. The collimator technique has proved to be effective for determination of half lives down to less than 10 ps

  8. Neutron radiography for nondestructive testing

    International Nuclear Information System (INIS)

    John, J.

    1979-01-01

    Neutron radiography is similar to X-ray inspection in that both depend upon use of radiation that penetrates some materials and is absorbed by others to provide a contrast image of conditions not readily available for visual inspection. X-rays are absorbed by dense materials, such as metals, whereas neutrons readily penetrate metals, but are absorbed by materials containing hydrogen. The neutron radiography has been successfully applied to a number of inspection situations. These include the inspection of explosives, advanced composites, adhesively bonded structures and a number of aircraft engine components. With the availability of Californium-252, it has become feasible to construct mobile neutron radiography systems suitable for field use. Such systems have been used for in-situ inspection of flight line aircraft, particularly to locate and measure hidden corrosion

  9. The CARIBU EBIS control and synchronization system

    Science.gov (United States)

    Dickerson, Clayton; Peters, Christopher

    2015-01-01

    The Californium Rare Isotope Breeder Upgrade (CARIBU) Electron Beam Ion Source (EBIS) charge breeder has been built and tested. The bases of the CARIBU EBIS electrical system are four voltage platforms on which both DC and pulsed high voltage outputs are controlled. The high voltage output pulses are created with either a combination of a function generator and a high voltage amplifier, or two high voltage DC power supplies and a high voltage solid state switch. Proper synchronization of the pulsed voltages, fundamental to optimizing the charge breeding performance, is achieved with triggering from a digital delay pulse generator. The control system is based on National Instruments realtime controllers and LabVIEW software implementing Functional Global Variables (FGV) to store and access instrument parameters. Fiber optic converters enable network communication and triggering across the platforms.

  10. Reliability of semiconductor and gas-filled diodes for over-voltage protection exposed to ionizing radiation

    Directory of Open Access Journals (Sweden)

    Stanković Koviljka

    2009-01-01

    Full Text Available The wide-spread use of semiconductor and gas-filled diodes for non-linear over-voltage protection results in a variety of possible working conditions. It is therefore essential to have a thorough insight into their reliability in exploitation environments which imply exposure to ionizing radiation. The aim of this paper is to investigate the influence of irradiation on over-voltage diode characteristics by exposing the diodes to californium-252 combined neutron/gamma radiation field. The irradiation of semiconductor over-voltage diodes causes severe degradation of their protection characteristics. On the other hand, gas-filled over-voltage diodes exhibit a temporal improvement of performance. The results are presented with the accompanying theoretical interpretations of the observed changes in over-voltage diode behaviour, based on the interaction of radiation with materials constituting the diodes.

  11. Designing on-line analyzer for coal on belt conveyor using neutron activation technique

    International Nuclear Information System (INIS)

    Rony Djokorayono; Agus Cahyono

    2014-01-01

    Basic design of on-line analyzer for coal on belt conveyor using neutron activation technique has been carried out. Compared with sampling technique, this neutron activation technique has some advantages in term of analysis accuracy and time. The design activities performed include the establishment of design requirements, functional requirements, technical requirements, technical specification, detection sub-system design, data acquisition subsystem design, and operator computer console design. This program will use Nal(Tl) scintillation detector to detect gamma-rays emitted by elements in coal due to neutron activation of a neutron source, "2"5"2Cf (Californium-252). This basic design of on-line analyzer for coal on belt conveyor using neutron activation technique should be followed up with the development of detailed design, prototype construction, and field testing. (author)

  12. Nuclear assay of coal. Volume 8. Continuous nuclear assay of coal (CONAC). Final report

    International Nuclear Information System (INIS)

    Lagarias, J.; Irminger, P.; Dodson, W.

    1979-01-01

    Using californium-252 as a source of exciting neutrons, prompt gamma photons emitted by elemental nuclei in the coal have been measured using several detectors, including sodium-iodide and germanium-lithium. Several coal types, including bituminous, subbituminous lignite and anthracite were crushed to various top sizes and analyzed carefully by traditional ASTM wet chemistry techniques at two or three different laboratories. The elements (sulfur, hydrogen, carbon, aluminum, silicon, iron, calcium, sodium, nitrogen, and chlorine) were determined by prompt neutron activations and the quantities compared with those of the wet chemical analyses. Since satisfactory correlation has been obtained at bench-scale level using 100 to 200 kG samples, an apparatus has been designed to analyze a coal stream of up to 50 ton/hour, at an electric power generating station

  13. Neutron dosimetry and spectrometry with Bonner spheres. Working out a log-normal reference matrix

    International Nuclear Information System (INIS)

    Zaborowski, Henrick.

    1981-11-01

    From the experimental and theoretical studies made upon the BONNER's spheres System with a I 6 Li(Eu) crystal and with a miniaturized 3 He counter we get the normalized energy response functions R*sub(i)(E). This normalization is obtained by the mathematization of the Resolution Function R*(i,E) in the Log-Normal distribution hypothesis to mono energetic neutrons given in April 1976 to the International Symposium on Californium 252. The fit of the Log-Normal Hypothesis with the experimental and Theoretical data is very satisfactory. The parameter's tabulated values allow a precise interpolation, at all energies between 0.4 eV and 15 MeV and for all spheres diameters between 2 and 12 inches, of the discretized R*sub(ij) Reference Matrix for the applications to neutron dosimetry and spectrometry [fr

  14. The CARIBU EBIS control and synchronization system

    Energy Technology Data Exchange (ETDEWEB)

    Dickerson, Clayton, E-mail: cdickerson@anl.gov; Peters, Christopher, E-mail: cdickerson@anl.gov [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2015-01-09

    The Californium Rare Isotope Breeder Upgrade (CARIBU) Electron Beam Ion Source (EBIS) charge breeder has been built and tested. The bases of the CARIBU EBIS electrical system are four voltage platforms on which both DC and pulsed high voltage outputs are controlled. The high voltage output pulses are created with either a combination of a function generator and a high voltage amplifier, or two high voltage DC power supplies and a high voltage solid state switch. Proper synchronization of the pulsed voltages, fundamental to optimizing the charge breeding performance, is achieved with triggering from a digital delay pulse generator. The control system is based on National Instruments realtime controllers and LabVIEW software implementing Functional Global Variables (FGV) to store and access instrument parameters. Fiber optic converters enable network communication and triggering across the platforms.

  15. Chemical consequences of radioactive decay. 1. Study of 249Cf ingrowth into crystalline 249BkBr3: a new crystalline phase of CfBr3

    International Nuclear Information System (INIS)

    Young, J.P.; Haire, R.G.; Peterson, J.R.; Ensor, D.D.; Fellows, R.L.

    1980-01-01

    Spectrophotometric and x-ray powder diffraction methods have been applied to a study of the ingrowth of californium-249 by β - decay of berkelium-249 in crystalline 249 BkBr 3 . It was found that the Cf daughter grows in with the same oxidation state and crystal structure as the parent. Thus, six-coordinate BkBr 3 (AlCl 3 -type monoclinic structure) generates six-coordinate CfBr 3 , and eight-coordinate BkBr 3 (PuBr 3 -type orthorhombic structure) generates eight-coordinate CfBr 3 , a previously unknown form of CfBr 3 . It was also found that the daughter Cf(III) in the BkBr 3 parent compound can be reduced to Cf(II) by treatment with H 2 , as it can in pure CfBr 3 . 5 figures

  16. Provenance and composition study on Terengganu inscribed stone using in-situ nuclear technology

    International Nuclear Information System (INIS)

    Jaafar Abdullah; Roslan Yahya; Hearie Hassan; Engku Mohd Fahmi Engku Chik; Mohamad Rabaie Shari; Airwan Affendi Mahmood; Abdul Quddoss Abu Bakar; Ainul Mardhiah Terry

    2012-01-01

    This paper focused on the analysis of trace elements and provenance study of the Inscribed Stone of Terengganu (BBPT) using Neutron-induced Prompt Gamma-Ray Techniques (NIPGAT). In this study, portable NIPGAT system was designed and developed by using volume-based measurement. It is a nondestructive testing technique for the samples. This system uses low activity of isotopic neutron radioactive source from californium-252 (Cf-252) as an irradiation source. Gamma ray spectroscopy as well as specialized computer software has been utilized to conduct the research. The study has determined that the stone was a dolerite stone based on the composition of the stone elements. Although most of the scientific data for this study have been collected, this project is still running to complete the scope of provenance study. (author)

  17. Nuclear fission and the transuranium elements

    International Nuclear Information System (INIS)

    Seaborg, G.T.

    1989-02-01

    Many of the transuranium elements are produced and isolated in large quantities through the use of neutrons furnished by nuclear fission reactions: plutonium (atomic number 94) in ton quantities; neptunium (93), americium (95), and curium (96) in kilogram quantities; berkelium (97) in 100 milligram quantities; californium (98) in gram quantities; and einsteinium (99) in milligram quantities. Transuranium isotopes have found many practical applications---as nuclear fuel for the large-scale generation of electricity, as compact, long-lived power sources for use in space exploration, as means for diagnosis and treatment in the medical area, and as tools in numerous industrial processes. Of particular interest is the unusual chemistry and impact of these heaviest elements on the periodic table. This account will feature these aspects. 9 refs., 5 figs

  18. Nuclear fission and the transuranium elements

    Energy Technology Data Exchange (ETDEWEB)

    Seaborg, G.T.

    1989-02-01

    Many of the transuranium elements are produced and isolated in large quantities through the use of neutrons furnished by nuclear fission reactions: plutonium (atomic number 94) in ton quantities; neptunium (93), americium (95), and curium (96) in kilogram quantities; berkelium (97) in 100 milligram quantities; californium (98) in gram quantities; and einsteinium (99) in milligram quantities. Transuranium isotopes have found many practical applications---as nuclear fuel for the large-scale generation of electricity, as compact, long-lived power sources for use in space exploration, as means for diagnosis and treatment in the medical area, and as tools in numerous industrial processes. Of particular interest is the unusual chemistry and impact of these heaviest elements on the periodic table. This account will feature these aspects. 9 refs., 5 figs.

  19. Dicty_cDB: Contig-U03903-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available A sequence from clone DKEYP-86F8 in l... 52 0.023 1 ( BV433213 ) S237P6285FG10.T0 Portuguese...6 1 ( BV438906 ) S237P6374FA9.T0 PortugueseWaterDog Canis familiar... 44 5.6 1 ( AM456273 ) Vitis vinifera c

  20. New records of Ascaridia platyceri (Nematoda) in parrots (Psittaciformes)

    Czech Academy of Sciences Publication Activity Database

    Kajerová, V.; Baruš, Vlastimil; Literák, I.

    2004-01-01

    Roč. 49, č. 7 (2004), s. 237-241 ISSN 0375-8427 R&D Projects: GA ČR GA524/03/0061 Institutional research plan: CEZ:AV0Z6093917 Keywords : ascarids * morphology * Nematoda Subject RIV: EG - Zoology Impact factor: 0.790, year: 2004 http://www.vri.cz/docs/vetmed/49-7-237.pdf

  1. Structural analysis within the Rožná and Olší uranium deposits (Strážek Moldanubicum) for the estimation of deformation and stress conditions of underground gas storage

    Czech Academy of Sciences Publication Activity Database

    Ptáček, Jiří; Melichar, R.; Hájek, Antonín; Koníček, Petr; Souček, Kamil; Staš, Lubomír; Kříž, P.; Lazárek, J.

    2013-01-01

    Roč. 10, č. 2 (2013), s. 237-246 ISSN 1214-9705 Institutional support: RVO:68145535 Keywords : structural analysis * deformation * stress * underground gas storage Subject RIV: DH - Mining, incl. Coal Mining Impact factor: 0.667, year: 2013 http://www.irsm.cas.cz/materialy/acta_content/2013_02/acta_170_13_Ptacek_237-246.pdf

  2. Actinide neutron induced cross-sections; analysis of the OSMOSE LWR-UO{sub 2} experiment in MINERVE

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, D.; Litaize, O.; Santamarina, A.; Antony, M.; Hudelot, J. P. [Commissariat a l' Energie Atomique, Cadarache, DEN/DER, 13108 Saint-Paul-Lez-Durance (France)

    2006-07-01

    This paper describes the interpretation of the first phase of the OSMOSE experimental program. The OSMOSE experiment began in 2005 in the MINERVE French facility and will continue until 2008. It consists in reactivity worth measurements of separated actinides by an oscillation technique. First results are obtained in a standard LWR neutron spectrum (UO{sub 2} lattice). The present study focuses on the following isotopes: {sup 234,236}U, {sup 237}Np, {sup 239,242}Pu. The comparison between APOLLO2 accurate deterministic calculations and experiments shows the reliability of the latest JEFF-3.1 European nuclear data library for all oscillated isotopes, except {sup 237}Np. The obtained (C/E-1){+-}({delta}E/E) values are the following: {sup 234}U: -5%{+-}2% {sup 237}Np: -11%{+-}2% {sup 239}Pu: +1%{+-}2% {sup 242}Pu: +2%{+-}2% An energetic decomposition of the reactivity worth is carried out using Standard Perturbation Theory that underlines the underestimation of the {sup 237}Np(n, {gamma}) thermal and resonant capture cross-section. (authors)

  3. 30 CFR 23.7 - Specific requirements for approval.

    Science.gov (United States)

    2010-07-01

    ... adequate instructions for the installation and connection of telephones and signal devices in order that the safety of these devices and other circuits shall not be diminished by improper installation. MSHA reserves the right to require the attachment of wiring diagrams to the cases of telephones and signal...

  4. Vocational Education in Corrections. Information Series No. 237.

    Science.gov (United States)

    Day, Sherman R.; McCane, Mel R.

    Vocational education programs in America's correctional institutions have been financially handicapped, since security demands the greatest portion of resource allocations. Four eras in the development of the correctional system are generally identified: era of punishment and retribution, era of restraint or reform, era of rehabilitation and…

  5. 29 CFR 1952.237 - Changes to approved plans.

    Science.gov (United States)

    2010-07-01

    ... 1910.142) in agriculture (except for agricultural temporary labor camps associated with egg, poultry or red meat production, or the post-harvest processing of agricultural or horticultural commodities.) The... Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR...

  6. 48 CFR 1252.237-72 - Prohibition on advertising.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Prohibition on advertising... Prohibition on advertising. As prescribed in (TAR) 48 CFR 1213.7101 and 1237.7003, insert the following clause: Prohibition on Advertising (JAN 1996) The contractor or its representatives (including training instructors...

  7. 48 CFR 652.237-71 - Identification/Building Pass.

    Science.gov (United States)

    2010-10-01

    ..., Information Security Programs Division, Industrial Security Branch (DS/ISP/INB) on its cleared employees..., Information Security Programs Division, Industrial Security Branch (DS/ISP/INB): (i) SF-85P, Questionnaire for... Pass (APR 2004) (a) Contractors working in domestic facilities who already possess a security clearance...

  8. 48 CFR 1252.237-71 - Certification of data.

    Science.gov (United States)

    2010-10-01

    ... (Public Law 104-106, 41 U.S.C. 425, note) and DOT Memorandum dated July 17, 1996. (a) The offeror...., company profile; qualifications; background statements; brochures) submitted with its offer is current, accurate, and complete as of the date of its offer. (b) The offeror understands that any inaccurate data...

  9. Determination of neptunium in soil by ICP-MS

    International Nuclear Information System (INIS)

    Ayranov, M.; Kraehenbuehl, U.

    2005-01-01

    A fast and simple method for the determination of 237 Np in soil is presented. The borate fusion decreases the sample pre-treatment time and a TEVA extraction chromatography separates neptunium from uranium and the interfering matrix components. A comparison of the sensitivities of alpha spectrometry and sector field ICP-MS for determination of 237 Np is presented. (orig.)

  10. Method for Determination of Neptunium in Large-Sized Urine Samples Using Manganese Dioxide Coprecipitation and 242Pu as Yield Tracer

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2013-01-01

    A novel method for bioassay of large volumes of human urine samples using manganese dioxide coprecipitation for preconcentration was developed for rapid determination of 237Np. 242Pu was utilized as a nonisotopic tracer to monitor the chemical yield of 237Np. A sequential injection extraction chr...... and rapid analysis of neptunium contamination level for emergency preparedness....

  11. Gastrointestinal absorption and retention of plutonium-238 in neonatal rats and swine

    International Nuclear Information System (INIS)

    Sullivan, M.F.

    1978-01-01

    Neonatal rats gavaged with 237 Pu or 238 Pu retained a substantial quantity in gut mucosa for a week but absorbed only 2.9% of the 237 Pu. After 140 days the amount retained fell to half that initially deposited. Newborn swine also retained large amounts in the gut and absorbed about 40% of the dose

  12. Dicty_cDB: Contig-U01557-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ling_GS-29-01-01-1... 30 5.1 3 ( BV439796 ) S237P619FE6.T0 PortugueseWaterDog Canis familiari... 36 5.1 2 ( ...enom... 42 8.1 1 ( BV424741 ) S237P6453FF6.T0 PortugueseWaterDog Canis familiar... 42 8.1 1 ( BV402984 ) S22

  13. Excited levels of Pa-233

    International Nuclear Information System (INIS)

    Vara Cuadrado, J. M.

    1969-01-01

    A study of Pa-233 excited levels from the alpha decay of Np-237 and from beta decay of Th-233 has been performed. The alpha decay spectrum was measured with a semiconductor spectrometer of 18 keV effective resolution (FWHM). Over 13 new lines were identified. The gamma ray spectra of Np-237 and Th-233 were obtained with a Ge-Li detector low and medium range energy lines, and with Si-Li detector for the low energy region. A continuous purification method of Np-237 from its comparatively short-lived daughter Pa-233 was applied. A high number of new lines were identified in both spectra. The gamma-gamma coincidence spectra were obtained with INa(T 1 ) detectors. (Author) 54 refs

  14. Excited levels of Pa-233; Niveles excitados del Pa-233

    Energy Technology Data Exchange (ETDEWEB)

    Vara Cuadrado, J M

    1969-07-01

    A study of Pa-233 excited levels from the alpha decay of Np-237 and from beta decay of Th-233 has been performed. The alpha decay spectrum was measured with a semiconductor spectrometer of 18 keV effective resolution (FWHM). Over 13 new lines were identified. The gamma ray spectra of Np-237 and Th-233 were obtained with a Ge-Li detector low and medium range energy lines, and with Si-Li detector for the low energy region. A continuous purification method of Np-237 from its comparatively short-lived daughter Pa-233 was applied. A high number of new lines were identified in both spectra. The gamma-gamma coincidence spectra were obtained with INa(T{sub 1}) detectors. (Author) 54 refs.

  15. Utilization of radiation facilities at TNRC for shielding researches and related topics

    Energy Technology Data Exchange (ETDEWEB)

    Akki, T S [Physics Department, Nuclear Physics and Radiation Shielding Division Tajura Nuclear Research Center, Tripoli (Libyan Arab Jamahiriya)

    1997-12-31

    This paper presents the running shielding research activities at Tajura Nuclear research center. The main area of researches are concentrated on the investigation of different types of concrete made from local materials such as conventional concrete, Magnetite-Limonite concrete, and heat resistant concrete. The measuring techniques used were neutron-gamma spectrometry, and activation foils. The measurements were performed using collimated beam of reactor neutrons emitted from one of the horizontal channels, as well as from californium-252 neutron source. The transmitted neutron spectra through concrete barriers of different thicknesses were measured by a scintillation spectrometer with NE-213 liquid organic scintillator. A non-destructive testing of some reactor materials were also carried out using neutron and gamma ray computerized tomography technique (CT). Some experiments were also carried out related to measurements of neutron depth dose distributions inside tissue equivalent materials. 10 figs.

  16. Dust grain charges in a nuclear-track plasma and the formation of dynamic vortex dust structures

    International Nuclear Information System (INIS)

    Rykov, V.A.; Khudyakov, A.V.; Filinov, V.S.; Vladimirov, V.I.; Deputatova, L.V.; Krutov, D.V.; Nefedov, A.P.; Fortov, V.E.

    2002-01-01

    Results are presented from Monte Carlo calculations of the electric charge of dust grains in a plasma produced during the slowing down of the radioactive decay products of californium nuclei in neon. The dust grain charging is explained for the first time as being due to the drift of electrons and ions in an external electric field. It is shown that the charges of the grains depend on their coordinates and strongly fluctuate with time. The time-averaged grain charges agree with the experimental data obtained on ordered liquidlike dust structures in a nuclear-track plasma. The time-averaged dust grain charges are used to carry out computer modeling of the formation of dynamic vortex structures observed in experiments. Evidence is obtained of the fact that the electrostatic forces experienced by the dust grains are potential in character

  17. Transuranic biokinetic parameters for marine invertebrates--a review.

    Science.gov (United States)

    Ryan, T P

    2002-04-01

    A catalogue of biokinetic parameters for the transuranic elements plutonium, americium, curium, neptunium, and californium in marine invertebrates is presented. The parameters considered are: the seawater-animal concentration factor (CF); the sediment-animal concentration ratio (CR); transuranic assimilation efficiency; transuranic tissue distribution and transuranic elimination rates. With respect to the seawater-animal CF, authors differ considerably on how they define this parameter and a seven-point reporting system is suggested. Transuranic uptake from sediment by animals is characterised by low CRs. The assimilation efficiencies of transuranic elements in marine invertebrates are high compared to vertebrates and mammals in general and the distribution of transuranics within the body tissue of an animal is dependent on the uptake path. The elimination of transuranics from most species examined conformed to a standard biphasic exponential model though some examples with three elimination phases were identified.

  18. Off-line commissioning of EBIS and plans for its integration into ATLAS and CARIBU

    Energy Technology Data Exchange (ETDEWEB)

    Ostroumov, P. N., E-mail: ostroumov@anl.gov; Barcikowski, A.; Dickerson, C. A.; Mustapha, B.; Perry, A.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2016-02-15

    An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed at Argonne to breed radioactive beams from the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne Tandem Linac Accelerator System (ATLAS). The EBIS-CB will replace the existing ECR charge breeder to increase the intensity and significantly improve the purity of reaccelerated radioactive ion beams. The CARIBU EBIS-CB has been successfully commissioned offline with an external singly charged cesium ion source. The performance of the EBIS fully meets the specifications to breed rare isotope beams delivered from CARIBU. The EBIS is being relocated and integrated into ATLAS and CARIBU. A long electrostatic beam transport system including two 180° bends in the vertical plane has been designed. The commissioning of the EBIS and the beam transport system in their permanent location will start at the end of this year.

  19. Off-line commissioning of EBIS and plans for its integration into ATLAS and CARIBU

    Science.gov (United States)

    Ostroumov, P. N.; Barcikowski, A.; Dickerson, C. A.; Mustapha, B.; Perry, A.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G.

    2016-02-01

    An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed at Argonne to breed radioactive beams from the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne Tandem Linac Accelerator System (ATLAS). The EBIS-CB will replace the existing ECR charge breeder to increase the intensity and significantly improve the purity of reaccelerated radioactive ion beams. The CARIBU EBIS-CB has been successfully commissioned offline with an external singly charged cesium ion source. The performance of the EBIS fully meets the specifications to breed rare isotope beams delivered from CARIBU. The EBIS is being relocated and integrated into ATLAS and CARIBU. A long electrostatic beam transport system including two 180° bends in the vertical plane has been designed. The commissioning of the EBIS and the beam transport system in their permanent location will start at the end of this year.

  20. Robotics and remote systems applications

    International Nuclear Information System (INIS)

    Rabold, D.E.

    1996-01-01

    This article is a review of numerous remote inspection techniques in use at the Savannah River (and other) facilities. These include: (1) reactor tank inspection robot, (2) californium waste removal robot, (3) fuel rod lubrication robot, (4) cesium source manipulation robot, (5) tank 13 survey and decontamination robots, (6) hot gang valve corridor decontamination and junction box removal robots, (7) lead removal from deionizer vessels robot, (8) HB line cleanup robot, (9) remote operation of a front end loader at WIPP, (10) remote overhead video extendible robot, (11) semi-intelligent mobile observing navigator, (12) remote camera systems in the SRS canyons, (13) cameras and borescope for the DWPF, (14) Hanford waste tank camera system, (15) in-tank precipitation camera system, (16) F-area retention basin pipe crawler, (17) waste tank wall crawler and annulus camera, (18) duct inspection, and (19) deionizer resin sampling

  1. Separation of 248Cm (III) from 252Cf (III) and its use in time resolved fluorescence spectroscopic (TRFS) studies

    International Nuclear Information System (INIS)

    Murali, M.S.; Nair, A.G.C.; Gujar, R.B.; Jain, A.; Tomar, B.S.; Godbole, S.V.; Reddy, A.V.R.; Manchanda, V.K.

    2008-07-01

    The present report gives a description of the methodology for the separation of 248 Cm(III) from decayed 252 Cf (III) waste solution. The waste solution was first assayed for 252 Cf content by neutron counting using a neutron well coincidence counter. The sample was subjected to the chemical separation of 248 Cm (III) from 252 Cf (III) following anion and cation exchange chromatography. The alpha spectrum of the separated curium fraction showed peaks due to 246 Cm and 248 Cm while the corresponding alpha spectrum of californium fraction showed 249,250,251,252 Cf. The gamma ray abundances of 249 Cf were determined with respect to its gamma rays of 387 keV and the data agreed well with that in literature. Separated Cm(III) was further characterized by recording its time resolved fluorescence spectrum (TRFS) in aqueous medium. (author)

  2. Modeling of lung cancer risk due to radon exhalation of granite stone in dwelling houses

    Directory of Open Access Journals (Sweden)

    Akbar Abbasi

    2017-01-01

    Conclusions: The estimated numbers of lung cancer deaths attributable to indoor radon due to granite stones in 2013 were 145 (3.33% and 103 (2.37% for poor and normal ventilation systems, respectively. According to our estimations, the values of 3.33% and 2.37% of lung cancer deaths in 2013 are attributed to radon exhalation of granite stones with poor and normal ventilation systems, respectively.

  3. 78 FR 73109 - Radio Broadcasting Services; Benjamin and Cisco, TX; De Beque, CO; Port Lions, AK; Rule and...

    Science.gov (United States)

    2013-12-05

    ... Broadcasting Services; Benjamin and Cisco, TX; De Beque, CO; Port Lions, AK; Rule and Shamrock, TX AGENCY... 237C3 at Benjamin, Texas; Channel 261C3 at Cisco, Texas; Channel 288C2 at Rule, Texas; and Channel 225C2..., Channel 237C3; by removing Cisco, Channel 261C3; by removing Channel 288C2 at Rule; and by removing...

  4. Testing of ENDF/B cross section data in the Californium-252 neutron benchmark field

    International Nuclear Information System (INIS)

    Mannhart, W.

    1979-01-01

    The fission neutron field of 252 Cf presently represents one of the most well-known neutron benchmark fields. For 13 neutron reactions which are of importance in reactor metrology, measurements of spectrum-averaged cross sections, [sigma], performed in this neutron field were compared with calculated average cross sections. This comparison allows one to draw conclusions as to the quality of different sigma(E) data taken from ENDF/B-IV, from ENDF/B-V, and from recent experiments and used in the calculation of average cross sections. The comparison includes an uncertainty analysis regarding the different uncertainty contributions of [sigma], of sigma(E), and of the spectral distribution of 252 Cf fission neutrons. Additionally, in a few examples, sensitivity studies were carried out. The sensitivity of the spectrum-averaged cross sections to individual characteristics of the sigma(E) data, such as normalization factors or shifts in the energy scale, was investigated. Similarly, the sensitivity of [sigma] to the spectral distribution of 252 Cf was determined. 4 figures, 2 tables

  5. Total neutron cross sections of berkelium-249 and californium-249 below 100 eV

    International Nuclear Information System (INIS)

    Benjamin, R.W.; Harvey, J.A.; Hill, N.W.; Pandey, M.S.; Carlton, R.F.

    1979-01-01

    The neutron total cross sections of 249 Bk and 249 Cf have been measured from 0.03 to 100 eV using the Oak Ridge Electron Linear Accelerator (ORELA) as a source of pulsed neutrons. The 1.6 mm dia. cylindrical transmission samples contained initially up to 5.3 mg of 98% 249 Bk and 2% 249 Cf: 4.5 years later, when the final measurements were made, the composition of the samples had become 2.5% 249 Bk, 96.9% 249 Cf, and 0.6% 245 Cm. Samples were cooled with liquid nitrogen to reduce Doppler broadening. Thirty-nine resonances were identified in 249 Bk and analyzed using a single-level Breit-Wigner formalism. Fifty-five resonances were identified in 249 Cf and analyzed using an R-matrix multilevel formalism. Fifty-five resonances were identified in 249 Cf and analyzed using an R-matrix multilevel formalism. The resonance parameters obtained have been used to determine the average level spacings and the s-wave neutron and fission strength functions. Where possible, bound-level parameters were derived to fit the thermal neutron total cross section data

  6. Profiling N-Type Dopants in Silicon

    Czech Academy of Sciences Publication Activity Database

    Hovorka, Miloš; Mika, Filip; Mikulík, P.; Frank, Luděk

    2010-01-01

    Roč. 51, č. 2 (2010), s. 237-242 ISSN 1345-9678 R&D Projects: GA ČR GP102/09/P543; GA AV ČR IAA100650803 Institutional research plan: CEZ:AV0Z20650511 Keywords : silicon * dopant contrast * photoemission electron microscopy * scanning electron microscopy Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.779, year: 2010 http://www.jim.or.jp/journal/e/51/02/237.html

  7. Value of MR-angiography in brain infarction

    International Nuclear Information System (INIS)

    Pirronello, Veronica; Capizzano, Aristides A.; Chouela, Carolina L.; Ternak, Alejandro; Ramirez, Susana; Mazzuco, Juan C.

    2004-01-01

    A retrospective study has been performed in a series of 237 patients, with brain and neck MR and MR angiography techniques. 108/237 (45.5%) patients presented either hemorrhage or lacunar and non lacunar ischemic stroke, 67 of which showed restricted diffusion. Diffusion and perfusion techniques can significantly contribute to study acute stroke. In our series MR angiography showed a 4% sensitivity to detect small arteries pathology. (author)

  8. Modeling of 830 nm FSO Link Attenuation in Fog or Wind Turbulence

    Czech Academy of Sciences Publication Activity Database

    Pešek, J.; Fišer, Ondřej; Svoboda, Jaroslav; Schejbal, V.

    2010-01-01

    Roč. 19, č. 2 (2010), s. 237-241 ISSN 1210-2512 R&D Projects: GA ČR GA102/08/0851; GA MŠk OC09027 Institutional research plan: CEZ:AV0Z30420517 Keywords : Free space optics propagation * fog attenuation, * wind turbulence attenuation * turbulent energy Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.503, year: 2010 http://www.radioeng.cz/fulltexts/2010/10_02_237_241.pdf

  9. Study on distribution and behavior of long-lived radionuclides in surface soil environment

    International Nuclear Information System (INIS)

    Morita, Shigemitsu; Watanabe, Hitoshi; Katagiri, Hiromi; Akatsu, Yasuo; Ishiguro, Hideharu

    1996-01-01

    Technetium-99 ( 99 Tc) and Neptunium-237 ( 237 Np) are important radionuclides for environmental assessment around nuclear fuel cycle facilities, because these have long-lives and relatively high mobility in the environment. Therefore, we have been studied the determination, distribution and behavior of such long-lived radionuclides in surface soil environment. A new analytical technique using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was applied to the determination of long-lived radionuclides in environmental samples. The determination method consists of dry ashing, anion exchange and solvent extraction to eliminate the interfering elements and ICP-MS measurement. The sensitivity of this method was 10 to 100,000 times higher, and the counting time was 300 to 100,000 times shorter than the conventional radioanalytical methods. The soil samples were collected at nine points and core soil sample was collected by an electric core sampler at one point. The core soil sample was divided into eight layers. The depth profiles showed that more than 90% of 99 Tc and 237 Np were retained in the surface layer up to 10cm in depth which contained much amount of organic materials. The results suggest that content of organic materials in soil is related to adsorption of 99 Tc and 237 Np onto soil. (author)

  10. Celecoxib-Induced Self-Assembly of Smart Albumin-Doxorubicin Conjugate for Enhanced Cancer Therapy.

    Science.gov (United States)

    Shi, Leilei; Xu, Li; Wu, Chenwei; Xue, Bai; Jin, Xin; Yang, Jiapei; Zhu, Xinyuan

    2018-03-14

    Recent years have witnessed the great contributions that drug combination therapy has made for enhanced cancer therapy. However, because of the complicated pharmacokinetics of combined drug formulations, the majority of combination strategies show severe adverse effects at high dosage and poor biodistribution in vivo. To overcome these deficiencies and achieve enhanced cancer therapy, we put forward a method to construct a smart albumin-based nanoplatform, denoted as K237-HSA-DC, for codelivery of cyclooxygenase-2 (COX-2) inhibitor (celecoxib) and chemotherapeutic agent (doxorubicin, DOX). Both in vitro and in vivo studies indicate that K237-HSA-DC exhibits the best therapeutic efficacy on tumor cells compared with all the other formulations. Moreover, K237-HSA-DC shows fewer side effects on normal organs in contrast to other formulations. To understand the reasons behind the improved drug efficacy in depth, we performed a cell metabonomics-based mechanism study and found that celecoxib could enhance the inhibitory effect of DOX on the transport of glucose into cells and then lead to subsequent significant energy metabolism inhibition. Considering the above-mentioned advantages of K237-HSA-DC, we believe the smart albumin-based nanoplatform can serve as a promising drug delivery system for enhanced cancer therapy.

  11. Aspects of 238Pu production in the experimental fast reactor JOYO

    International Nuclear Information System (INIS)

    Osaka, Masahiko; Koyama, Shin-ichi; Tanaka, Kenya; Itoh, Masahiko; Saito, Masaki

    2005-01-01

    Experimental determination of 238 Pu in 237 Np samples irradiated in the experimental fast reactor JOYO was done as part of the demonstration of 238 Pu production from 237 Np in fast reactors within the framework of the protected Pu production project, which aims at reinforcement of proliferation resistance of Pu by increasing the 238 Pu isotopic ratio. 238 Pu production amount in the irradiated 237 Np samples was determined by a radioanalytical technique. Aspects of 238 Pu production were examined on the basis of the present radioanalysis. The 238 Pu production amount depends on the neutron spectrum which can range from that of a typical fast reactor to a nearly epi-thermal spectrum. It is concluded that the fast reactor has not only high potential for use in protected Pu production, but also as an incinerator for excess Pu

  12. Transuranium Processing Plant semiannual report of production, status, and plans for period ending June 30, 1975

    Energy Technology Data Exchange (ETDEWEB)

    King, L.J.; Bigelow, J.E.; Collins, E.D.

    1976-03-01

    During the period January 1, 1975, through June 30, 1975, the following amounts of transuranium elements were recovered from 22 irradiated HFIR targets: 2g /sup 243/Am, 59 g /sup 244/Cm, 51 mg /sup 249/Bk, 465 mg /sup 252/Cf, 2.5 mg /sup 253/Es, and 1.4 pg /sup 257/Fm. In addition, 45 mg of high-purity /sup 248/Cm was operated from /sup 252/Cf which had been recovered and purified during earlier periods, and 56 mg of a lower-quality /sup 248/Cm was separated from californium purification rework solutions. Five HFIR targets, each containing approximately 9 g of actinides (predominantly curium), were fabricated. A new long-term projection showed that /sup 252/Cf production in the TRU-HFIR complex could increase to as much as 2.5 g/year. During the next 18 months, we expect to recover totals of 46 mg of /sup 249/Bk, 520 mg of /sup 252/Cf, 2.0 mg of /sup 253/Es (in a mixture of isotopes), 220 ..mu..g of high-purity /sup 253/Es, and 1.6 pg of /sup 257/Fm. We also expect to obtain 125 mg of high-purity /sup 248/Cm from purified californium now in storage. There are no plans to process any of the remaining SRP Pu-Al tubes or to irradiate any plutonium targets in the HFIR; thus, we do not expect to recover any /sup 244/Pu. No changes were made in the chemical processing flowsheets normally used at TRU. Two neutron sources were fabricated, bringing the total fabricated to 77. In special projects, we (1) produced about 1 mg of /sup 250/Cf by irradiation of /sup 249/Bk in HFIR rabbits, and (2) processed some irradiated /sup 248/Cm samples and obtained yield and isotopic composition data for use in determining the capture cross section of /sup 249/Cm in the HFIR. The values that are currently being used for transuranium element decay data and for cross-section data in planning irradiation-processing cycles, calculating production forecasts, and assaying products are tabulated in the Appendix.

  13. Serosurveillance of Scrub Typhus in Small Mammals Collected from Military Training Sites near the DMZ, Northern Gyeonggi-do, Korea, and Analysis of the Relative Abundance of Chiggers from Mammals Examined

    Science.gov (United States)

    2010-09-01

    Korean J Paras/to/. Vol. 48, No. 3: 237-243, September 2010 DOl: JO.J3471kjp.2010.48.J.237 Serosurveillance of Scrub Typhus in Small Mammals...65th Medical BrigadeAJSAMEDDAC-Korea, Unit# 15281, APO AP 96205-5281, USA Abstract: Comprehensive quarterly serosurveillance on scrub typhus in small...rarely observed (prevalence < 1 0%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4

  14. 48 CFR 237.102-72 - Contracts for management services.

    Science.gov (United States)

    2010-10-01

    ... development or production of the major system ensures that Federal employees are responsible for determining— (1) Courses of action to be taken in the best interest of the Government; and (2) Best technical performance for the warfighter; and (c) The contract requires that the prime contractor for the contract may...

  15. 48 CFR 1852.237-73 - Release of sensitive information.

    Science.gov (United States)

    2010-10-01

    ... technology system for NASA that contains sensitive information, the service provider's contract shall include the clause at 1852.204-76, Security Requirements for Unclassified Information Technology Resources. The Security Requirements clause requires the service provider to implement an Information Technology...

  16. All projects related to | Page 237 | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Impact of Tobacco Tax Increases in Latin America. Project. Raising taxes ... Region: North and Central America, South America, Argentina, Bolivia, Brazil, Chile, Colombia, Mexico, Peru. Program: Food, Environment, and Health. Total Funding: ...

  17. Neptunium 237 behaviour in subcellular fractions of rat kidneys

    International Nuclear Information System (INIS)

    Kreslov, V.V.; Maksutova, A.Ya.; Mushkacheva, G.S.

    1978-01-01

    Subcellular distribution of intravenously injected (1 and 0.5 μCi/rat) neptunium nitrate (5- and 6-valent) in kidneys of rat males and females has been investigated. It has been shown that the radionuclide was unevenly distributed within the cell. As early as 24 hours after administration, about 50 per cent of neptunium were concentrated in the mitochondrial fraction. The data are presented on variations in neptunium behaviour within subcellular fractions of rat kidneys depending on the sex of animals, valency and dose of the isotope

  18. 237 Missionary Historiography: A Factor for the Emergence of ...

    African Journals Online (AJOL)

    User

    2012-01-24

    Jan 24, 2012 ... Nmah, P. E. - Department of Religion and Human Relations, Nnamdi ... It is also the identification of a people with the aspirations and interests of their .... edifices where they congregate for worship, and yet cannot say from their ... robot- like worshippers of the prophet Isaiah's description ( Isaiah 29: 13), or.

  19. 48 CFR 1852.237-72 - Access to Sensitive Information.

    Science.gov (United States)

    2010-10-01

    ... position in another procurement. (2) Safeguard sensitive information coming into its possession from... relating to ethics, conflicts of interest, corruption, and other criminal or civil matters relating to the...

  20. 49 CFR 237.71 - Determination of bridge load capacities.

    Science.gov (United States)

    2010-10-01

    ... capacity shall be determined. (g) Bridge load capacity may be expressed in terms of numerical values related to a standard system of bridge loads, but shall in any case be stated in terms of weight and...) Bridge load capacity may be expressed in terms of both normal and maximum load conditions. Operation of...

  1. 48 CFR 1552.237-70 - Contract publication review procedures.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Contract publication review... journal article to the Project Officer, and one copy to the Contracting Officer. (d) If the Government has... AGENCY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses...

  2. Microscopic nature of inhomogeneous line broadening: Analysis of the excitation-line-narrowing spectra of Cf4+ in CeF4

    International Nuclear Information System (INIS)

    Liu, G.K.; Huang, J.; Beitz, J.V.

    1993-01-01

    Optical transitions between 5f states of tetravalent californium ion doped (1 metal-atom %) into CeF 4 exhibit unusually large inhomogeneous broadening. The nature of the inhomogeneous broadening in this system has been studied by using fluorescence line narrowing and excitation line narrowing (ELN). It is shown that the energy distributions of different electronic states of Cf 4+ in this system are correlated. In the ELN experiments, reduced excitation linewidth was obtained when selectively monitoring fluorescence emission. A linear relation was observed between the excitation energies of crystal-field states of the 5 G 4' manifold and the fluorescence wavelength monitored across the inhomogeneous profile of a 5 G 6' -- 7 F 6' transition. Analysis of these results by means of a microscopic theory proposed by Laird and Skinner [J. Chem. Phys. 90, 3880 (1989)] has provided insights into the structural properties of this disordered system

  3. Chelation and stabilization of berkelium in oxidation state +IV

    Science.gov (United States)

    Deblonde, Gauthier J.-P.; Sturzbecher-Hoehne, Manuel; Rupert, Peter B.; An, Dahlia D.; Illy, Marie-Claire; Ralston, Corie Y.; Brabec, Jiri; de Jong, Wibe A.; Strong, Roland K.; Abergel, Rebecca J.

    2017-09-01

    Berkelium (Bk) has been predicted to be the only transplutonium element able to exhibit both +III and +IV oxidation states in solution, but evidence of a stable oxidized Bk chelate has so far remained elusive. Here we describe the stabilization of the heaviest 4+ ion of the periodic table, under mild aqueous conditions, using a siderophore derivative. The resulting Bk(IV) complex exhibits luminescence via sensitization through an intramolecular antenna effect. This neutral Bk(IV) coordination compound is not sequestered by the protein siderocalin—a mammalian metal transporter—in contrast to the negatively charged species obtained with neighbouring trivalent actinides americium, curium and californium (Cf). The corresponding Cf(III)-ligand-protein ternary adduct was characterized by X-ray diffraction analysis. Combined with theoretical predictions, these data add significant insight to the field of transplutonium chemistry, and may lead to innovative Bk separation and purification processes.

  4. Operation manual for the INEL on-line mass-separator facility

    International Nuclear Information System (INIS)

    Anderl, R.A.

    1984-06-01

    This report is an operation manual for an on-line mass-separator facility which is located in Building 661 at the Test Reactor Area of the Idaho National Engineering Laboratory. The facility provides mass-separated sources of short-lived fission-product radionuclides whose decay properties can be studied using a variety of nuclear spectroscopic techniques. This facility is unique in that it utilizes the gas-jet technique to transport fission products from a 252 Cf source located in a hot cell to the ion source of the mass separator. This document includes the following: (a) a detailed description of the facility, (b) identification of equipment hazards and safety controls, (c) detailed operating procedures for startup, continuous operation and shutdown, (d) operating procedures for the californium hot cell, and (e) an operator's manual for the automated moving tape collector/data acquisition system. 7 references, 16 figures, 8 tables

  5. Operational safety at the radiometallurgy laboratory of Fontenay-aux-Roses

    International Nuclear Information System (INIS)

    Hayet, Lucien; Petit, Pierre; Conche, Roger.

    1976-01-01

    Opened in 1967, the Radiometallurgy Laboratory is responsible for the examination of plutonium 239 based nuclear fuels of breeder reactors such as Rapsodie and Phenix. Part of the same laboratory is also responsible for the manufacture of californium 252 sources. These neutron sources can have a neutron fluency yield of 2,3 10 10 n/s/4π (i.e. 10mg of 252cf). This large laboratory includes a total area of 117m 2 of hot surfaces. It also includes 14 high activity cells with a capacity of 100000Ci at 1MeV. Located only 7km from the center of Paris, it must incorporate a special design and a particularly sure safety policy. Several statistics are given: irradiations, contaminations, incidents, quantity of fissile material, solid and liquid wastes etc... The principles of safety management are outlined and an analysis given of this basic nuclear facility [fr

  6. Situation Desperate: U.S. Army Engineer Disaster Relief Operations, Origins to 1950

    Science.gov (United States)

    2011-01-01

    the Sabine River sub- office, for example, relayed the following sad report to headquarters: “I regret to report the loss of all property in my...doctor with typhoid vaccine ; the cows and horses and dogs of every description wandering up and down the levees; the fur- niture, every kind of...215 Sabine River, 59 Sacramento Engineer District, 237, 238 Sacramento River, 186, 237 St. Francis River, 85, 87 St. Joe River, 217 St. Louis Engineer

  7. Dollar Summary of Prime Contract Awards by State, Place, and Contractor, FY84, Part 4, (Allenville, Missouri-Wyoming, Pennsylvania).

    Science.gov (United States)

    1984-01-01

    CLOSED CIRCUIT TV CORP 26 26INGERSOLL-RAND COMPANY INC 67 67INSTITUTE FOR ADVANCED STUDY 75 75 INTERNATIONAL BUSINESS MCHS 28 28M L ENERGIA INC 30...I 28 PRINCETON E 0 & 0 PARC 28 IBM CORP 25 25 M L ENERGIA INC 107 107 SAN LUIS CAMERA 41 41...SANDERS ASSOCIATES INC 848 848 SATELLITE SERVICES INC 237 237 SCHICKEL H GEN CONTR INC 132 132 SHERLOT HOME RENOVATION CORP 317 317 TRACY TROMBLEY CONT

  8. Analysis of trace neptunium in the vicinity of underground nuclear tests at the Nevada National Security Site.

    Science.gov (United States)

    Zhao, P; Tinnacher, R M; Zavarin, M; Kersting, A B

    2014-11-01

    A high sensitivity analytical method for (237)Np analysis was developed and applied to groundwater samples from the Nevada National Security Site (NNSS) using short-lived (239)Np as a yield tracer and HR magnetic sector ICP-MS. The (237)Np concentrations in the vicinity of the Almendro, Cambric, Dalhart, Cheshire, and Chancellor underground nuclear test locations range from nuclear tests at very low but measureable concentrations. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Multiplicity and correlated energy of gamma rays emitted in the spontaneous fission of Californium-252

    International Nuclear Information System (INIS)

    Brunson, G.S. Jr.

    1982-06-01

    An array of eight high-speed plastic scintillation detectors has been used to infer a mathematical model for the emission multipliciy of prompt gammas in the spontaneous fission of 252 Cf. Exceptional time resolution and coincidence capability permitted the separation of gammas from fast neutrons over a flight path of approximately 10 cm. About 20 different distribution models were tested. The average energy of the prompt gammas is inversely related to the number emitted; however, this inverse relationship is not strong and the total gamma energy does increase with increasing gamma number. An extension of the experiment incorporated a lithium-drifted germanium gamma spectrometer that resolved nearly 100 discrete gammas associated with fission. Of these gammas, some were preferentially associated with fission in which few gammas were emitted. Certain others were more frequent when many gammas were emitted. Results are presented

  10. Remarkably High Stability of Late Actinide Dioxide Cations: Extending Chemistry to Pentavalent Berkelium and Californium.

    Science.gov (United States)

    Dau, Phuong D; Vasiliu, Monica; Peterson, Kirk A; Dixon, David A; Gibson, John K

    2017-12-06

    Actinyl chemistry is extended beyond Cm to BkO 2 + and CfO 2 + through transfer of an O atom from NO 2 to BkO + or CfO + , establishing a surprisingly high lower limit of 73 kcal mol -1 for the dissociation energies, D[O-(BkO + )] and D[O-(CfO + )]. CCSD(T) computations are in accord with the observed reactions, and characterize the newly observed dioxide ions as linear pentavalent actinyls; these being the first Bk and Cf species with oxidation states above IV. Computations of actinide dioxide cations AnO 2 + for An=Pa to Lr reveal an unexpected minimum for D[O-(CmO + )]. For CmO 2 + , and AnO 2 + beyond EsO 2 + , the most stable structure has side-on bonded η 2 -(O 2 ), as An III peroxides for An=Cm and Lr, and as An II superoxides for An=Fm, Md, and No. It is predicted that the most stable structure of EsO 2 + is linear [O=Es V =O] + , einsteinyl, and that FmO 2 + and MdO 2 + , like CmO 2 + , also have actinyl(V) structures as local energy minima. The results expand actinide oxidation state chemistry, the realm of the distinctive actinyl moiety, and the non-periodic character towards the end of the periodic table. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Neutron Protection Factor Determination and Validation for a Vehicle Surrogate Using a Californium Fission Source

    Science.gov (United States)

    2017-06-01

    study the laws governing shock wave propagation, and evaluate the suitability of military operations after being subjected to their use. During...14]. MCNP6.1 then outputs a dose spectrum, instead of the standard fluence spectrum created from the “ f4 ” tally [14]. In order to produce the dose...manually, an unmodified fluence tally ( f4 ) was exported externally to a spreadsheet. The energy bins were summed and grouped to mimic the energy bin

  12. Solvent extraction of irradiated neptunium targets. I. Valence stabilization

    International Nuclear Information System (INIS)

    Thompson, G.H.; Thompson, M.C.

    1977-01-01

    Solvent extraction of 237 Np and 238 Pu from irradiated neptunium is being investigated as a possible replacement for the currently used anion exchange process at the Savannah River Plant. Solvent extraction would reduce separations costs and waste volume and increase the production rate. The major difficulty in solvent extraction processing is maintaining neptunium and plutonium in the extractable IV or VI valence states during initial extraction. This study investigated the stability of these states. Results show that: The extractable M(IV) valence states of neptunium and plutonium are mutually unstable in plant dissolver solution (2 g/l 237 Np, 0.4 g/l 238 Pu, 1.2M Al 3+ , 4.6M NO 3 - , and 1M H + ). The reaction rates producing inextractable species from extractable M(IV) or M(VI) are fast enough that greater than or equal to 99.9 percent extractable species in 237 Np-- 238 Pu mixtures cannot be maintained for a practicable processing period

  13. Selective localization of neptunium-237 in the nuclei of mammalian cells. Localisation selective du neptunium-237 au sein des noyaux des cellules de mammiferes

    Energy Technology Data Exchange (ETDEWEB)

    Galle, P.; Boulahdour, H. (Faculte de Medecine, 94 - Creteil (FR)); Metivier, H. (CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses, 92 (FR). Inst. de Protection et de Surete Nucleaire)

    1992-01-01

    After injection in the rat of soluble neptunium salt, the distribution of this element was studied at the subcellular level by electron microscopy and electron probe microanalysis. Abnormal structures have been observed by electron microscopy in the nuclei of hepatocytes, and the same structures have also been observed in the nuclei of the proximal tubules cells of the kidney. These structures are formed of clusters of very small and dense particles, several nanometers in diameter. The clusters are localized in the central part of the nuclei and they are separate from nucleoli and heterochromatin. Electron probe X-ray analysis of this cluster have shown that they contain neptunium associated with phosphorus. In the cell containing neptunium inclusions, other non specific lesions are also observed (nuclear pycnosis, mitochondrial depletion).

  14. Child Pornography. An Exploratory Study

    Science.gov (United States)

    1990-01-01

    The Sexual Exploitation of Children. New York: St Martins Press, 1986. Fields, Howa’-4 "Supreme Court, 6-3, Sans Possossiron of Child Porn ...Court, 6-3, Bans Possession of Child Porn ," Publishers Weekly 237, no.18 (May 4, 1990) 10. 27 See: O’Brien, 65-78; Seth L. Goldstein, "Investigating...15, (1973). 3 New York v. Ferber, 458 U.S. 757, (1982). 4 Howard Fields, "Supreme Court, 6-3, Bans Possession of Child Porn ,’" Publishers Weekly 237

  15. Biology of neptunium

    International Nuclear Information System (INIS)

    Wirth, R.E.

    1985-11-01

    This work contains detailed information about fractional absorption of neptunium through gastrointestinal tract in vivo as well as about organ and subcellular distribution in rats. Biochemical investigations have shown, that neptunium is bound to the iron transport protein transferrin in the blood serum. A long-term experiment resulted in osteosarkomincidences of 11% (0.2 mp Np-237/kg) and 36% (1 mg Np-237/kg); simultaneous the whole-body retention was measured during the natural lifespan of the animals of 2.5 years. (orig.) [de

  16. Transport of neptunium through Yucca Mountain tuffs

    International Nuclear Information System (INIS)

    Triay, I.R.; Robinson, B.A.; Mitchell, A.J.; Overly, C.M.; Lopez, R.M.

    1993-01-01

    Neptunium has a high solubility in groundwaters from Yucca Mountain [1]. Uranium in nuclear reactors produces 237 Np which has a half-life of 2.1 4 x 10 6 years. Consequently, the transport of 237 Np through tuffs is of major importance in assessing the performance of a high-level nuclear waste repository at Yucca Mountain. The objective of this work is to determine the amount of Np retardation that is provided by the minerals in Yucca Mountain tuffs as a function of groundwater chemistry

  17. The significance of chromosome deletions in atomic-bomb survivors

    International Nuclear Information System (INIS)

    Tanaka, Kimio; Shigeta, Chiharu; Oguma, Nobuo; Kamada, Nanao; Deng, Z.; Niimi, Masanobu; Aisaka, Tadaichi.

    1986-01-01

    In 39 A-bomb survivors 40 years after exposure at ≤ 1,000 m from ground zero, the frequency and features of chromosome deletions in peripheral lymphocytes were examined using a differential staining technique. Simultaneously, in vitro irradiation experiment with Cf-252 was made to infer chromosome aberrations occuring immediately after exposure. Californium-252 with 100 rad induced dicentric and ring chromosomes in 40 % of the cells and acentric fragments in 44 %. Among the A-bomb survivors, chromosome aberrations were observed in 651 (21 %) of the total 3,136 cells. There were 146 cells with deletions (22 % of abnormal cells; 5 % of the total cells), and 10 cells with acentric fragment (0.3 % of the total cells). The figure for deletions was far higher than that reported in the literature. A large number of deletions were seen in chromosomes no.4, no.21, and no.22, and a few deletions in chromosomes no.7 and no.20. Significance of chromosome deletions is discussed. (Namekawa, K.)

  18. Cleanex process: a versatile solvent extraction process for recovery and purification of lanthanides, americium, and curium

    International Nuclear Information System (INIS)

    Bigelow, J.E.; Collins, E.D.; King, L.J.

    1979-01-01

    At a concentration of 1 M in straight-chain hydrocarbon diluent, HDEHP will extract americium, curium, and other trivalent actinide and lanthanide elements from dilute acid or salt solutions. The solute is back-extracted with more concentrated acid, either nitric or hydrochloric. The process has been used in the continuous, countercurrent mode, but its greatest advantage arises in batch extractions where the excess acid can be titrated with NaOH to produce a final acidity of about 0.03 M. Under these conditions, 99% recovery can be achieved, usually in one stage. Cleanex was used on the 50-liter scale at the Transuranium Processing Plant at Oak Ridge for 12 years to provide a broad spectrum cleanup to transuranium elements before applying more sophisticated techniques for separating individual products. The process is also used routinely to recover excessive losses of curium and/or californium from plant waste streams. The solvent system is relatively resistant to radiation damage, being usable up to 200 W-h/liter

  19. Dynamic vortex dust structures in a nuclear-track plasma

    International Nuclear Information System (INIS)

    Rykov, V A; Khudyakov, A V; Filinov, V S; Vladimirov, V I; Deputatova, L V; Krutov, D V; Fortov, V E

    2003-01-01

    Results are presented from Monte Carlo calculations of the electric charge on dust grains in a plasma produced during the slowing down of radioactive decay products of californium nuclei in neon. The dust grain charging is explained as being due to the drift of electrons and ions in an external electric field. It is shown that the charges of the grains depend on their coordinates and strongly fluctuate with time. The time-averaged grain charges agree with the experimental data obtained on ordered liquid-like dust structures in a nuclear-track plasma. The time-averaged dust grain charges are used to carry out computer modelling of the formation of dynamic vortex structures observed in experiments. Evidence is obtained for the fact that the electrostatic forces experienced by the dust grains are potential in character. The paper is supplemented by a video clip showing the typical dynamics of the simulated vortex dust structure

  20. Monitoring taconite process streams with thermal neutron capture-gamma ray analysis. Report of investigations/1980

    International Nuclear Information System (INIS)

    Woodbury, F.B.W.

    1980-12-01

    The Bureau of Mines is evaluating alternative technologies to treat oxidized taconites. Since process control is an essential element in the application of these process technologies, research was performed on a prototype monitoring system utilizing a californium-252 (252-Cf) neutron source and a thermal neutron capture-gamma ray spectra analysis method to measure the amount of iron and percent solids in process slurries. The prototype system was used to monitor the concentrate and tailing streams in a 900-lb/hr flotation pilot plant during continuous around-the-clock tests. The iron content of the process slurries was determined by measuring the total peak areas under the capture spectrum peaks at 7.626-7.632 MeV, the associated escape peaks at 7.136-7.122 and 6.626-6.612 MeV, and the iron doublets at 4.900 and 4.998 MeV. A potential method for determining the percent solids in process slurries using the 2.22 MeV hydrogen capture peak is discussed

  1. A survey of uses and users of 252Cf

    International Nuclear Information System (INIS)

    Bigelow, J.E.; Alexander, C.W.; King, L.J.; Knauer, J.B.; Notz, K.J.

    1989-01-01

    Californium-252, which is one of the transuranium-element isotopes being produced in the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL), has found many applications in service to industry and medicine. As a neutron source, 252 Cf is unique in providing a highly concentrated and extremely reliable neutron spectrum from a very small assembly. Over the past 22 years, 252 Cf has been applied with great success to cancer therapy, to neutron radiography of objects ranging from flowers to entire aircraft, to startup sources for nuclear reactors, to fission activation assay for quality control and safeguards of all commercial nuclear fuel, and to many other beneficial uses, some of which are now poised for further growth. The extensive exploitation of this highly specialized product has been made possible through 252 Sales/Loan programs sponsored by the US DOE Office of Nuclear Materials Production, initially at the Savannah River Laboratory and now at ORNL

  2. Reactor production of 252Cf and transcurium isotopes

    International Nuclear Information System (INIS)

    Alexander, C.W.; Halperin, J.; Walker, R.L.; Bigelow, J.E.

    1990-01-01

    Berkelium, californium, einsteinium, and fermium are currently produced in the High Flux Isotope Reactor (HFIR) and recovered in the Radiochemical Engineering Development Center (REDC) at the Oak Ridge National Laboratory (ORNL). All the isotopes are used for research. In addition, 252 Cf, 253 Es, and 255 Fm have been considered or are used for industrial or medical applications. ORNL is the sole producer of these transcurium isotopes in the western world. A wide range of actinide samples were irradiated in special test assemblies at the Fast Flux Test Facility (FFTF) at Hanford, Washington. The purpose of the experiments was to evaluate the usefulness of the two-group flux model for transmutations in the special assemblies with an eventual goal of determining the feasibility of producing macro amounts of transcurium isotopes in the FFTF. Preliminary results from the production of 254g Es from 252 Cf will be discussed. 14 refs., 5 tabs

  3. Actinide metals

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Paul L. [Geochem Australia, Kiama, NSW (Australia); Ekberg, Christian [Chalmers Univ. of Technology, Goeteborg (Sweden). Nuclear Chemistry/Industrial Materials Recycling

    2016-07-01

    All isotopes of actinium are radioactive and exist in aqueous solution only in the trivalent state. There have been very few studies on the hydrolytic reactions of actinium(III). The hydrolysis reactions for uranium would only be important in alkaline pH conditions. Thermodynamic parameters for the hydrolysis species of uranium(VI) and its oxide and hydroxide phases can be determined from the stability and solubility constants. The hydrolytic behaviour of neptunium(VI) is quite similar to that of uranium(VI). The solubility constant of NpO{sub 2}OH(am) has been reported a number of times for both zero ionic strength and in fixed ionic strength media. Americium can form four oxidation states in aqueous solution, namely trivalent, tetravalent, pentavalent and hexavalent. Desire, Hussonnois and Guillaumont determined stability constants for the species AmOH{sup 2+} for the actinides, plutonium(III), americium(III), curium(III), berkelium(III) and californium(III) using a solvent extraction technique.

  4. Actinide metals

    International Nuclear Information System (INIS)

    Brown, Paul L.; Ekberg, Christian

    2016-01-01

    All isotopes of actinium are radioactive and exist in aqueous solution only in the trivalent state. There have been very few studies on the hydrolytic reactions of actinium(III). The hydrolysis reactions for uranium would only be important in alkaline pH conditions. Thermodynamic parameters for the hydrolysis species of uranium(VI) and its oxide and hydroxide phases can be determined from the stability and solubility constants. The hydrolytic behaviour of neptunium(VI) is quite similar to that of uranium(VI). The solubility constant of NpO 2 OH(am) has been reported a number of times for both zero ionic strength and in fixed ionic strength media. Americium can form four oxidation states in aqueous solution, namely trivalent, tetravalent, pentavalent and hexavalent. Desire, Hussonnois and Guillaumont determined stability constants for the species AmOH 2+ for the actinides, plutonium(III), americium(III), curium(III), berkelium(III) and californium(III) using a solvent extraction technique.

  5. Nuclear Chemistry Institute, Mainz University. Annual Report 1995

    International Nuclear Information System (INIS)

    Denschlag, H.O.

    1996-03-01

    The annual report of the Institut fuer Kernchemie addresses inter alia three main research activities. The first belongs to the area of basic research, covering studies in the fields of nuclear fission, chemistry of the super-heavy elements and of heavy-ion reactions extending from the Coulomb barrier to relativistic energies, and nuclear astrophysics in connection with the ''r process''. By means of laser technology, high-precision data could be measured of the ionization energies of berkelium and californium. Studies of atomic clusters in the vacuum of an ionization trap revealed interesting aspects. The second major activity was devoted to the analysis of environmental media, applying inter alia neutron activation analysis and resonance ionization mass spectroscopy (RIMS). The third activity resulted in the development of novel processes, or the enhancement of existing processes or methods, for applications in basic research work and in environmental analytics. Another item of interest is the summarizing report on the operation of the TRIGA research reactor. (orig./SR) [de

  6. Test and evaluation results of the 252Cf shuffler at the Savannah River Plant

    International Nuclear Information System (INIS)

    Crane, T.W.

    1981-03-01

    The 252 Cf Shuffler, a nondestructive assay instrument employing californium neutron source irradiation and delayed-neutron counting, was developed for measuring 235 U content of scrap and waste items generated at the Savannah River Plant (SRP) reactor fuel fabrication facility. The scrap and waste items include high-purity uranium-aluminum alloy ingots as well as pieces of castings, saw and lathe chips from machining operations, low-purity items such as oxides of uranium or uranium intermixed with flux materials found in recovery operations, and materials not recoverable at SRP such as floor sweepings or residues from the uranium scrap recovery operation. The uranium contains about 60% 235 U with the remaining isotopes being 236 U, 238 U, and 234 U in descending order. The test and evaluation at SRP concluded that the accuracy, safety, reliability, and ease of use made the 252 Cf Shuffler a suitable instrument for routine use in an industrial, production-oriented plant

  7. General purpose nuclear irradiation chamber

    International Nuclear Information System (INIS)

    Nurul Fadzlin Hasbullah; Nuurul Iffah Che Omar; Nahrul Khair Alang Md Rashid; Jaafar Abdullah

    2013-01-01

    Nuclear technology has found a great need for use in medicine, industry, and research. Smoke detectors in our homes, medical treatments and new varieties of plants by irradiating its seeds are just a few examples of the benefits of nuclear technology. Portable neutron source such as Californium-252, available at Industrial Technology Division (BTI/ PAT), Malaysian Nuclear Agency, has a 2.645 year half-life. However, 252 Cf is known to emit gamma radiation from the source. Thus, this chamber aims to provide a proper gamma shielding for samples to distinguish the use of mixed neutron with gamma-rays or pure neutron radiation. The chamber is compatible to be used with other portable neutron sources such as 241 Am-Be as well as the reactor TRIGA PUSPATI for higher neutron dose. This chamber was designed through a collaborative effort of Kulliyyah Engineering, IIUM with the Industrial Technology Division (BTI) team, Malaysian Nuclear Agency. (Author)

  8. Experimental Studies on Plutonium Kinetics in Marine Biota

    International Nuclear Information System (INIS)

    Fowler, S.; Heyraud, M.; Beasley, T.M.

    1976-01-01

    Laboratory experiments were undertaken to measure plutonium flux through marine organisms and to clarify the pathways by which this important element is cycled in the marine environment. The use of a specially prepared isotope, plutonium-237, allowed measurements to be made with standard Nal(Tl) scintillation techniques. Mussels, shrimp and worms were allowed to accumulate plutonium-237 from sea water for up to 25 days. Accumulation by shrimp was relatively slow and the degree of uptake was strongly influenced by moulting. Cast moults contained large fractions of the shrimps ' plutonium content, indicating the high affinity of plutonium for surface areas. Only small amounts of the isotope in the moult are lost to water; hence, moulting is considered to be an important biological parameter in the biogeochemical cycling of plutonium. Mussels attained higher concentration factors than shrimp with most of the accumulated isotope (> 80%) located in the shell. Byssus threads often contained large fractions of the mussels' plutonium-237 content and reached concentration factors as high as 4100. Worms readily accumulated plutonium-237 in either the +4 or +6 state, reaching concentration factors of approximately 200, Retention studies indicated a relatively slow loss of plutonium-237 from all animals studied. In the case of mussels, a computed half-time for a large fraction of the animals plutonium content was of the order of 2 years. The more rapid loss from shrimp (Tb 1/2 = 1.5 months) was due principally to the large fraction of plutonium lost at moult. Food chain studies with shrimp indicated that tissue build-up via plutonium ingestion would be a slow process. Total excretion was not entirely a result of passing contaminated food through the gut; approximately 15% of the ingested plutonium was removed from the contaminated food and subsequently excreted by processes other than defaecation of labelled food. Ratios of four different plutonium isotopes used in

  9. Experimental studies on plutonium kinetics in marine biota

    International Nuclear Information System (INIS)

    Fowler, S.; Heyraud, M.; Beasley, T.M.

    1975-01-01

    Laboratory experiments were undertaken to measure plutonium flux through marine organisms and to clarify the pathways by which this important element is cycled in the marine environment. The use of a specially prepared isotope, plutonium-237, allowed measurements to be made with standard NaI(Tl) scintillation techniques. Mussels, shrimp and worms were allowed to accumulate plutonium-237 from seawater for up to 25 days. Accumulation by shrimp was relatively slow and the degree of uptake was strongly influenced by moulting. Cast moults contained large fractions of the shrimps' plutonium content, indicating the high affinity of plutonium for surface areas. Only small amounts of the isotope in the moult are lost to water; hence, moulting is considered to be an important biological parameter in the biogeochemical cycling of plutonium. Mussels attained higher concentration factors than shrimp with most of the accumulated isotope (>80%) located in the shell. Byssus threads often contained large fractions of the mussels' plutonium-237 content and reached concentration factors as high as 4100. Worms readily accumulated plutonium-237 in either the +4 or +6 state, reaching concentration factors of approximately 200. Retention studies indicated a relatively slow loss of plutonium-237 from all animals studied. In the case of mussels, a computed half-time for a large fraction of the animals' plutonium content was of the order of 2 years. The more rapid loss from shrimp (Tbsub(1/2)=1.5 months) was due principally to the large fraction of plutonium lost at moult. Food chain studies with shrimp indicated that tissue build-up via plutonium ingestion would be a slow process. Total excretion was not entirely a result of passing contaminated food through the gut; approximately 15% of the ingested plutonium was removed from the contaminated food and subsequently excreted by processes other than defaecation of labelled food. Ratios of four different plutonium isotopes used in the

  10. ORF Alignment: NC_000854 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... Length = 237 ... Query: 64 ... LLVVVTFPGLKSDVELIACSGDRVIEIYNPGVDPHEAQLDPRAARMVAEAD...IVVTGGHTP 123 ... LLVVVTFPGLKSDVELIACSGDRVIEIYNPGVDPHEAQLDPRAARMVAEADIVVTGGHTP Sbjct: 1 ... LLVVVTFPGLKSDVELIACSGDRVIEIYNPGVDPHE

  11. ORF Alignment: NC_006348 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available 98 ... Query: 237 IVAAARDYVLAHRSRPVGVPELCEQLHVSRRTLQYCFQDVLGMAPATYLRALRLNGVRRD 296 ... IVAAARDYVLAHRSRP...VGVPELCEQLHVSRRTLQYCFQDVLGMAPATYLRALRLNGVRRD Sbjct: 1 ... IVAAARDYVLAHRSRPVGVPELCEQLHVSRRTLQYCFQDVLGMAPATYLRALRLNGVRRD 60 ...

  12. Exploring the Presence of microDNAs in Prostate Cancer Cell Lines, Tissue, and Sera of Prostate Cancer Patients and its Possible Application as Biomarker

    Science.gov (United States)

    2016-04-01

    ES2 OVCAR8 LnCap PC-3 C4-2 Cell Count 1.8X108 1x108 1.1X108 1.24X108 1.1X108 Episomal DNA (ug) 21.3 23.7 26 15.6 20.4 Starting DNA (ug) 21.3 23.7...kidney, liver, lung, skeletal muscle, spleen, sperm , testis and thymus) (5). EccDNA sequences were then enriched by multiple displacement amplification...including sperm . MicroDNAs arise preferentially from areas with high gene density, GC content, and exon density from promoters with activating chro

  13. Source-driven noise analysis measurements with neptunium metal reflected by high enriched uranium

    International Nuclear Information System (INIS)

    Valentine, Timothy E.; Mattingly, John K.

    2003-01-01

    Subcritical noise analysis measurements have been performed with neptunium ( 237 Np) sphere reflected by highly enriched uranium. These measurements were performed at the Los Alamos Critical Experiment Facility in December 2002 to provide an estimate of the subcriticality of 237 Np reflected by various amounts of high-enriched uranium. This paper provides a description of the measurements and presents some preliminary results of the analysis of the measurements. The measured and calculated spectral ratios differ by 15% whereas the 'interpreted' and calculated k eff values differ by approximately 1%. (author)

  14. ORF Alignment: NC_002977 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ... Length = 112 ... Query: 237 RIELHGVNFKYDSAELTDSAKRILDETAENLILFPEKRDIEVAGHTSTEGT...NEYNMRLSI 296 ... RIELHGVNFKYDSAELTDSAKRILDETAENLILFPEKRDIEVAGHTSTEGTNEYNMRLSI Sbjct: 1 ... RIELHGVNFKYDSAELTDSAKRILDETAENLILFPEKRDIEVAGHTSTEGTNEYNMRLSI 60 ...

  15. A feasibility study on long-life reduced-moderation water reactor with highly protected Pu breeding by doping with minor actinides

    International Nuclear Information System (INIS)

    Hamase, Erina; Damian, Frederic; Poinot-salanon, Christine; Saito, Masaki; Sagara, Hiroshi; Han, Chi Young

    2013-01-01

    Highlights: ► The present paper is focused on a reduced-moderation water reactor. ►237 Np or 241 Am was doped into the inner blanket. ►238 Pu transmuted from MA works as a fissionable nuclide. ► It also contributes to increasing the proliferation resistance of Pu. ► Long-life core and highly protected Pu breeding were simultaneously achieved. - Abstract: The present paper is focused on the feasibility of reduced-moderation water reactor (RMWR) which could simultaneously achieve the extension of core life-time, and highly protected plutonium (Pu) breeding performance with short compound system doubling time (CSDT) by neptunium-237 ( 237 Np) or americium-241 ( 241 Am) doping of the inner blanket of the RMWR. As a preliminary analysis of the RMWR, a simplified fuel pin configuration was analyzed. In case of 60% doping of 237 Np and 241 Am in the inner blanket, the maximum available effective full power days (EFPDs) were much longer and were about 15,100 and 14,200 EFPDs, respectively. For the proliferation resistance of Pu produced in the blanket, the total Pu in the inner and lower/upper blanket was below the practically unusable criterion for an explosive device proposed by Pellaud, and was technically unfeasible for high-technology hypothetical nuclear explosive devices (HNEDs) proposed by Kessler and Kimura. The protected Pu breeding performance was analyzed and in case of 60% doping of 237 Np and 241 Am, CSDT was short by approximately 40 and 50 years. Therefore, the feasibility of RMWR was shown which could simultaneously achieve the extension of core life-time and have highly protected Pu breeding performance with short CSDT by doping the inner blanket with minor actinides (MAs). The objective of this study was thus to evaluate the performance of the concept with respect to the core life-time, proliferation resistance of Pu and CSDT. The technological feasibility of such core concept will have to be evaluated by further dedicated analyses

  16. 48 CFR 252.237-7013 - Instruction to offerors (bulk weight).

    Science.gov (United States)

    2010-10-01

    ...) Offers shall be submitted on a unit price per pound of serviced laundry. Unit prices shall include all costs to the Government of providing the service, including pickup and delivery charges. (b) The Contracting Officer will evaluate bids based on the estimated pounds of serviced laundry stated in the...

  17. 48 CFR 252.237-7023 - Continuation of Essential Contractor Services.

    Science.gov (United States)

    2010-10-01

    ... provide a written plan for continuing the performance of essential contractor services identified in...; and (v) The approach for communicating expectations to contractor employees regarding their roles and... or other designated representative as expeditiously as possible and use its best efforts to cooperate...

  18. 48 CFR 52.237-4 - Payment by Government to Contractor.

    Science.gov (United States)

    2010-10-01

    ... Officer shall retain 10 percent of the estimated payment until final completion and acceptance of the... full, without retaining a percentage. Also, on completion and acceptance of each unit or division for which the price is stated separately, the Contracting Officer may authorize full payment for that unit...

  19. 237 Impacts socio-sanitaires et environnementaux de la gestion des ...

    African Journals Online (AJOL)

    SWEET

    pollution des eaux, érosion des berges des mayo et alluvionnement des drains, amènent à suggérer des ... D'après TUCCI [1], les principaux défis de la gestion des inondations sont liés à l'occupation des ... populations aux impacts des inondations de plaine est due, d'après TUCCI [1], au manque de connaissance.

  20. 237 Interrogating Nollywood and its Sources of Funding: The Case ...

    African Journals Online (AJOL)

    The problem of funding continues to haunt start-ups in Africa and there seems to be ... hospitality business where funding, which catalyses the efforts of independent ..... find her testimony too easy, but Emem Isong made the above statement in ...

  1. P2-37: Processing Affordance Information from Invisible Tool Images

    Directory of Open Access Journals (Sweden)

    Shinho Cho

    2012-10-01

    Full Text Available A recent study showed that viewing manipulable objects such as images of tools induces the neural activation of posterior parietal areas. This neural activation is observed even when visual awareness of the image is visually suppressed. (Fang and He, 2005 Nature Neuroscience 10 1380–1385; Almeida et al, 2010 Psychological Science 21 772–778. However, the specific visuomotor information in tool images that drives the activation of dorsal areas is still unclear. We measured priming effect of invisible tool prime (left or right handed orientation. Observers distinguished the orientation of target tools (appropriate for left vs right handed grip briefly presented following visually suppressed primes (Experiment1. Also we measured the suppression time of tool images whose handle direction was presented in a left- or right-handed orientation. A dynamic noise pattern was presented to one of the observer's eyes at full contrast, while images of tools (left or right handed were simultaneously presented to the left or right visual field of the other eye. The subjects were asked to respond to the appearance of any partial or full part of the test image (Experiment 2. Results showed that (1 observers responded faster in the congruent condition (the same orientation between prime and target and (2 tool images shown in the right visual field took less time to gain dominance against the dynamic noise. These results suggest that even without overt recognition of presented tools, an object's affordance can be registered and processed in the brain. A recent study showed that viewing manipulable objects such as images of tools induces the neural activation of posterior parietal areas. This neural activation is observed even when visual awareness of the image is visually suppressed (Almeida et al., 2010 Psychological Science 21 772–778; Fang and He, 2005 Nature Neuroscience 10 1380–1385. However, the specific visuomotor information in tool images that drives the activation of dorsal areas is still unclear. We measured the priming effect of invisible tool prime (left or right handed orientation. Observers distinguished the orientation of target tools (appropriate for left vs. right handed grip briefly presented following visually suppressed primes (Experiment 1. Also we measured the suppression time of tool images whose handle direction was presented in a left- or right-handed orientation. A dynamic noise pattern was presented to one of the observer's eyes at full contrast, while images of tools (left or right handed were simultaneously presented to the left or right visual field of the other eye. The subjects were asked to respond to the appearance of any partial or full part of the test image (Experiment 2. Results showed that (1 observers responded faster in the congruent condition (the same orientation between prime and target and (2 tool images shown in the right visual field took less time to gain dominance against the dynamic noise. These results suggest that even without overt recognition of presented tools, an object's affordance can be registered and processed in the brain.

  2. 48 CFR 252.237-7018 - Special definitions of Government property.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Special definitions of... ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT...) Articles delivered to the Contractor to be laundered or dry-cleaned, including any articles which are...

  3. Validation of Cross Sections with Criticality Experiment and Reaction Rates: the Neptunium Case

    CERN Document Server

    Leong, L S; Audouin, L; Berthier, B; Le Naour, C; Stéphan, C; Paradela, C; Tarrío, D; Duran, I

    2014-01-01

    The Np-237 neutron-induced fission cross section has been recently measured in a large energy range (from eV to GeV) at the n\\_TOF facility at CERN. When compared to previous measurements the n\\_TOF fission cross section appears to be higher by 5-7\\% beyond the fission threshold. To check the relevance of the n\\_TOF data, we considered a criticality experiment performed at Los Alamos with a 6 kg sphere of Np-237, surrounded by uranium highly enriched in U-235 so as to approach criticality with fast neutrons. The multiplication factor k(eff) of the calculation is in better agreement with the experiment when we replace the ENDF/B-VII. 0 evaluation of the Np-237 fission cross section by the n\\_TOF data. We also explored the hypothesis of deficiencies of the inelastic cross section in U-235 which has been invoked by some authors to explain the deviation of 750 pcm. The large modification needed to reduce the deviation seems to be incompatible with existing inelastic cross section measurements. Also we show that t...

  4. Laser ablation of silicate glasses doped with transuranic actinides

    International Nuclear Information System (INIS)

    Gibson, J.K.; Haire, R.G.

    1998-01-01

    Direct sampling laser ablation plasma mass spectrometry (DS-LAMS) was applied to silica glasses doped with 237 Np, 242 Pu or 241 Am using a unique instrument recently installed into a transuranic glovebox. The primary goal was to assess the utility of mass spectrometry of directly ablated ions for facile evaluation of actinide (An) constituents of silicate glass immobilization matrices used for encapsulation of radionuclides. The instrument and general procedures have been described elsewhere. Three high-purity silicate glasses prepared by a sol-gel process (SG) and one conventional high-temperature (HT; melting point ∼ 1,450 C) borosilicate glass were studied. These glasses comprised the following constituents, with compositions expressed in mass percentages: Np-HT ∼ 30% SiO 2 + 6% B 2 O 3 + 3% BaO + 13% Al 2 O 3 + 10% PbO + 30% La 2 O 3 + 8% 237 NpO 2 ; Np-SG ∼ 70% SiO 2 + 30% 237 NpO 2 ; Pu-SG ∼ 70% SiO 2 + 30% 242 PuO 2 ; Am-SG ∼ 85% SiO 2 + 15% 241 AmO 2

  5. Perceptions of preclinical medical students towards extracurricular activities.

    Science.gov (United States)

    Almasry, Mazen; Kayali, Zeina; Alsaad, Rakan; Alhayaza, Ghada; Ahmad, Mohammad Sharique; Obeidat, Akef; Abu-Zaid, Ahmed

    2017-08-16

    To determine the percentage of students involved in extracurricular activities (EAs), explore relationships between participation in EAs and students' characteristics, and investigate students' perceptions (i.e., motives and barriers) towards participation in EAs. An online, anonymous, random, cross-sectional, self-rating survey was administered during spring 2015-2016 to second-year and third-year students (n=340). Chi-square test was used to explore relationships between participation in EAs and students' characteristics. Mann-Whitney U-test was used to compare the mean 5-point Likert scale responses according to students' characteristics. Statistical significance was determined as pstudents participated in the survey (n=237/340, response rate: 69.7%). Only 143 students (60.3%, n=140/237) participated in EAs, and this percentage significantly differed by gender (χ 2 (1, N=237)=4.3205, pstudents regarding the following barrier: "affect academic performance negatively" (U=5389.5, psatisfactory, and positively related to students' characteristics of male gender, non-Saudi nationality and high cGPA. Medical schools should facilitate all potential motives and resolve all associated barriers towards participation in EAs.

  6. High-sensitivity fast neutron detector KNK-2-7M

    Energy Technology Data Exchange (ETDEWEB)

    Koshelev, A. S., E-mail: alexsander.coshelev@yandex.ru; Dovbysh, L. Ye.; Ovchinnikov, M. A.; Pikulina, G. N.; Drozdov, Yu. M. [Russian Federal Nuclear Center All-Russian Research Institute of Experimental Physics (Russian Federation); Chuklyaev, S. V. [Research Institute of Materials Technology (Russian Federation)

    2015-12-15

    The construction of the fast neutron detector KNK-2-7M is briefly described. The results of the study of the detector in the pulse-counting mode are given for the fissions of {sup 237}Np nuclei in the radiator of the neutron-sensitive section and in the current mode with the separation of sectional currents of functional sections. The possibilities of determining the effective number of {sup 237}Np nuclei in the radiator of the neutronsensitive section are considered. The diagnostic possibilities of the detector in the counting mode are shown by example of the analysis of the reference data from the neutron-field characteristics in the working hall of the BR-K1 reactor. The diagnostic possibilities of the detector in the current operating mode are shown by example of the results of measuring the {sup 237}Np-fission intensity in the BR-K1 reactor power start-ups implemented in the mode of fission-pulse generation on delayed neutrons at the detector arrangement inside the reactor core cavity under conditions of a wide variation of the reactor radiation field.

  7. Application of fission track detectors to californium-252 neutron dosimetry in tissue near the radiation source

    International Nuclear Information System (INIS)

    Oswald, R.A.; Lanzl, L.H.; Rozenfeld, M.

    1981-01-01

    Fission track detectors were applied to a unique problem in neutron dosimetry. Measurements of neutron doses were required at locations within a tumor of 1 cm diameter implanted on the back of a mouse and surrounded by a square array of four 252 Cf medical sources. Measurements made in a tissue-equivalent mouse phantom showed that the neutron dose rate to the center of the tumor was 2.18 rads mg -1 h -1 +- 8.4%. The spatial variation of neutron dose to the tumor ranged from 1.88 to 2.55 rads mg -1 h -1 . These measurements agree with calculated values of neutron dose to those locations in the phantom. Fission track detectors have been found to be a reliable tool for neutron dosimetry for geometries in which one wishes to know neutron dose values which may vary considerably over distances of 1 cm or less

  8. Application of fission track detectors to californium-252 neutron dosimetry in tissue near the radiation source

    International Nuclear Information System (INIS)

    Oswald, R.A.; Lanzl, L.H.; Rozenfeld, M.

    1981-01-01

    Fission track detectors were applied to a unique problem in neutron dosimetry. Measurements of neutron doses were required at locations within a tumor of 1 cm diameter implanted on the back of a mouse and surrounded by a square array of four 252 Cf medical sources. Measurements made in a tissue-equivalent mouse phantom showed that the neutron dose rate to the center of the tumor was 2.18 rads micrograms-1 h-1 +/- 8.4%. The spatial variation of neutron dose to the tumor ranged from 1.88 to 2.55 rads micrograms-1 h-1. These measurements agree with calculated values of neutron dose to those locations in the phantom. Fission track detectors have been found to be a reliable tool for neutron dosimetry for geometries in which one wishes to know neutron dose values which may vary considerably over distances of 1 cm or less

  9. Development and validation of RP-HPLC and UV-spectrophotometric methods for rapid simultaneous estimation of amlodipine and benazepril in pure and fixed dose combination

    Directory of Open Access Journals (Sweden)

    Abhi Kavathia

    2017-05-01

    Full Text Available High-performance liquid chromatographic (HPLC and UV spectrophotometric methods were developed and validated for the quantitative determination of amlodipine besylate (AM and benazepril hydrochloride (BZ. Different analytical performance parameters such as linearity, precision, accuracy, specificity, limit of detection (LOD and limit of quantification (LOQ were determined according to International Conference on Harmonization ICH Q2B guidelines. The RP-HPLC method was developed by the isocratic technique on a reversed-phase Shodex C-18 5e column. The retention time for AM and BZ was 4.43 min and 5.70 min respectively. The UV spectrophotometric determinations were performed at 237 nm and 366 nm for AM and at 237 nm for BZ. Correlation between absorbance of AM at 237 nm and 366 nm was established and based on developed correlation equation estimation of BZ at 237 nm was carried out. The linearity of the calibration curves for each analyte in the desired concentration range was good (r2 > 0.999 by both the HPLC and UV methods. The method showed good reproducibility and recovery with percent relative standard deviation less than 5%. Moreover, the accuracy and precision obtained with HPLC co-related well with the UV method which implied that UV spectroscopy can be a cheap, reliable and less time consuming alternative for chromatographic analysis. The proposed methods are highly sensitive, precise and accurate and hence successfully applied for determining the assay and in vitro dissolution of a marketed formulation.

  10. Non-conventional measurement techniques for the determination of some long-lived radionuclides produced in nuclear fuel

    International Nuclear Information System (INIS)

    Rosenberg, R.J.

    1992-04-01

    The results of a literature survey on non-radiometric analytical techniques for the determination of long-lived radionuclides are described. The methods which have been considered are accelerator mass spectrometry, inductively coupled plasma mass spectrometry, thermal ionization mass spectrometry, resonance ionization spectrometry, resonance ionization mass spectrometry and neutron activation analysis. Neutron activation analysis has been commonly used for the determination of 129 I and 237 Np in environmental samples. Inductively coupled mass spectrometry seems likely to become the method of choice for the determination of 99 Tc, 237 Np and Pu-isotopes. The methods are discussed and the chemical separation methods described. (orig.)

  11. Contribution to the experimental study of transuranian element (Pu, Am, Cm) transfers between the various phases (particles, water, organisms) of the sedimentary system

    International Nuclear Information System (INIS)

    Grillo, M.C.

    1982-06-01

    The methodology of this work is first given. Transfer kinetics of 237 Pu, 241 Am and 242 Cm between seawater and macrofauna of loose substrates are studied. The effect of temperature and salinity over the transfers of 237 Pu, 241 Am and 242 Cm between water and bivalve mollusk Tapes decussatus is then studied. This work deals also with transfer kinetics of these elements between carnivorous organisms of the loose substrates and their preys. A preliminary study of 241 Am transfers between two phases, particles and interstitial water is finally presented: role of benthic burrowing organisms [fr

  12. ORF Alignment: NC_004722 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available kinase ... [Bacillus cereus ATCC 14579] ... Length = 81 ... Query: 237 MRKRLKESIEMQTQYEENRKELISNISHDLKTPITSIIGYVEGIKDGVANT...PEKMDKYLT 296 ... MRKRLKESIEMQTQYEENRKELISNISHDLKTPITSIIGYVEGIKDGVANT...PEKMDKYLT Sbjct: 1 ... MRKRLKESIEMQTQYEENRKELISNISHDLKTPITSIIGYVEGIKDGVANTPEKMDKYLT 60 ...

  13. Radioactivity studies. Progress report, January 1-December 31, 1982

    International Nuclear Information System (INIS)

    Cohen, N.

    1983-06-01

    During the last year, the research program in actinide biokinetics in nonhuman primates has been expanded to include preliminary studies of the element neptunium. Recently, Np-237, which is known to be present in high-level nuclear reactor waste, has received increased attention as a potential long-range hazard to man. In addition to the neptunium studies, the metabolism of protactinium-233, the daughter of Np-237, has been investigated. Although characterization of Pa-233 metabolism was originally conducted in order to correct for Pa-233 interference during in vivo and in vitro gamma spectrometry of Np-237, several other considerations indicated that Pa might be of radiological concern itself and should thereby warrant further investigation. Due to the limited amount of data in the literature defining the biokinetics of both neptunium and protactinium, metabolis studies of these nuclides are now being conducted in adult female baboons in a manner similar to that which has been successfully performed at this laboratory for Am-241 and Cm-243,244. Procedures routinely performed include external whole-body counting, excreta collection (separation and measurement), blood sampling, biopsies of liver and bone, and complete tissue and organ analysis after sacrifice

  14. Over-expression of p53 mutants in LNCaP cells alters tumor growth and angiogenesis in vivo

    International Nuclear Information System (INIS)

    Perryman, L.A.; Blair, J.M.; Kingsley, E.A.; Szymanska, B.; Ow, K.T.; Wen, V.W.; MacKenzie, K.L.; Vermeulen, P.B.; Jackson, P.; Russell, P.J.

    2006-01-01

    This study has investigated the impact of three specific dominant-negative p53 mutants (F134L, M237L, and R273H) on tumorigenesis by LNCaP prostate cancer cells. Mutant p53 proteins were associated with an increased subcutaneous 'take rate' in NOD-SCID mice, and increased production of PSA. Tumors expressing F134L and R273H grew slower than controls, and were associated with decreased necrosis and apoptosis, but not hypoxia. Interestingly, hypoxia levels were increased in tumors expressing M237L. There was less proliferation in F134L-bearing tumors compared to control, but this was not statistically significant. Angiogenesis was decreased in tumors expressing F134L and R273H compared with M237L, or controls. Conditioned medium from F134L tumors inhibited growth of normal human umbilical-vein endothelial cells but not telomerase-immortalized bone marrow endothelial cells. F134L tumor supernatants showed lower levels of VEGF and endostatin compared with supernatants from tumors expressing other mutants. Our results support the possibility that decreased angiogenesis might account for reduced growth rate of tumor cells expressing the F134L p53 mutation

  15. Hemoglobinopathies in newborns from Salvador, Bahia, Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Adorno Elisângela Vitória

    2005-01-01

    Full Text Available Hemoglobinopathies are hereditary disorders of the hemoglobin molecule with a high prevalence worldwide. Brazil has a prevalence of 0.1 to 0.3% of newborns with sickle cell anemia and 20.0 to 25.0% of heterozygous alpha2 thalassemia among African Brazilians. In the present study, we investigated the presence of variant hemoglobins and alpha2(3.7 Kb and alpha2(4.2 Kb thalassemia in newborns from Salvador, Bahia, Brazil. Samples of umbilical cord blood from a total of 590 newborns were analyzed, of which 57 (9.8% were FAS; 36 (6.5% FAC; one (0.2% SF; and five (0.9% FSC. One hundred fourteen (22.2% newborns had alpha2(3.7 Kb thalassemia, of whom 101 (19.7% were heterozygous and 13 (2.5% homozygous, showing statistical significance for hematological data between newborns with normal alpha genes and alpha2(3.7 Kb thalassemia carriers. The alpha2(4.2 Kb thalassemia was not found. Frequencies found in the present study confirm that hemoglobinopathies are a public health problem in Brazil, emphasizing the need for neonatal screening and genetic counseling programs.

  16. A single nucleotide in stem loop II of 5'-untranslated region contributes to virulence of enterovirus 71 in mice.

    Directory of Open Access Journals (Sweden)

    Ming-Te Yeh

    Full Text Available BACKGROUND: Enterovirus 71 (EV71 has emerged as a neuroinvasive virus responsible for several large outbreaks in the Asia-Pacific region while virulence determinant remains unexplored. PRINCIPAL FINDINGS: In this report, we investigated increased virulence of unadapted EV71 clinical isolate 237 as compared with isolate 4643 in mice. A fragment 12 nucleotides in length in stem loop (SL II of 237 5'-untranslated region (UTR visibly reduced survival time and rate in mice was identified by constructing a series of infectious clones harboring chimeric 5'-UTR. In cells transfected with bicistronic plasmids, and replicon RNAs, the 12-nt fragment of isolate 237 enhanced translational activities and accelerated replication of subgenomic EV71. Finally, single nucleotide change from cytosine to uridine at base 158 in this short fragment of 5'-UTR was proven to reduce viral translation and EV71 virulence in mice. Results collectively indicated a pivotal role of novel virulence determinant C158 on virus translation in vitro and EV71 virulence in vivo. CONCLUSIONS: These results presented the first reported virulence determinant in EV71 5'-UTR and first position discovered from unadapted isolates.

  17. ORF Alignment: NC_006274 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available kinase ... [Bacillus cereus ATCC 14579] ... Length = 81 ... Query: 237 MRKKLKESIEMQTQYEENRKELISNISHDLKTPITSIIGYVEGIKDGVANT...PEKMDKYLT 296 ... MRK+LKESIEMQTQYEENRKELISNISHDLKTPITSIIGYVEGIKDGVANT...PEKMDKYLT Sbjct: 1 ... MRKRLKESIEMQTQYEENRKELISNISHDLKTPITSIIGYVEGIKDGVANTPEKMDKYLT 60 ...

  18. {open_quotes}Transmutation efficiency calculation in the blanket on melted salts with central neptunium target{close_quotes}

    Energy Technology Data Exchange (ETDEWEB)

    Kolesov, V.F.; Shtarev, S.K.; Khoruzhiy, V.K. [Russia Federal Nuclear Center, Arzamas (Russian Federation)] [and others

    1995-10-01

    In the limits of ABC project version of two-sectional reactor system in the form of combination of subcritical blanket on melted salts and multiplying target from threshold fissile material {sup 237}Np is considered. This research is the development of the VNIIEF`s earlier work`s (Russia) investigating of usage possibilities in ABC project the conception of multisectional blankets with single-sided neutron coupling between sections. With the help of Monte-Carlo program the calculations results of system mentioned are given. The possibility of accelerator`s considerable power reduction at the account of thorium target substitution with neptunium-237 multiplying target is shown.

  19. In-situ elemental analysis of coal by neutron activation

    International Nuclear Information System (INIS)

    Mikesell, J.L.; Senftle, F.E.; Tanner, A.B.

    1986-01-01

    The U.S. Geological Survey (USGS) has worked to develop neutron techniques for the borehole measurement of the elemental composition of ores since 1969, and first demonstrated a borehole ultimate analysis of coal in 1977. Borehole measurements such as these permit real-time evaluation of coal quality without the expense of coring or the delays associated with laboratory analyses. Two technological innovations make such measurements possible: the availability, from Savannah River Operations Office, DOE, of small californium-252 (/sup 252/Cf) fission neutron sources, and the development, by USGS and Princeton Gamma-Techn, of the melting-cryogen-cooled high-purity germanium borehole gamma-ray detector. A technique of relating mass fractions to measured gamma-ray intensities, which eliminates the need for detailed knowledge of the geometry of the neutron distribution, is used to calculate elemental compositions without resorting to the test pits or computer borehole modeling. In coal, all of the major constituents (C, H, N, S, Si, Al, Fe, Ti) except oxygen can be determined quantitatively by thermal neutron capture gamma-ray spectroscopy

  20. Report on the workshop "Decay spectroscopy at CARIBU: advanced fuel cycle applications, nuclear structure and astrophysics". 14-16 April 2011, Argonne National Laboratory, USA.

    Energy Technology Data Exchange (ETDEWEB)

    Kondev, F.; Carpenter, M.P.; Chowdhury, P.; Clark, J.A.; Lister, C.J.; Nichols, A.L.; Swewryniak, D. (Nuclear Engineering Division); (Univ. of Massachusetts); (Univ. of Surrey)

    2011-10-06

    A workshop on 'Decay Spectroscopy at CARIBU: Advanced Fuel Cycle Applications, Nuclear Structure and Astrophysics' will be held at Argonne National Laboratory on April 14-16, 2011. The aim of the workshop is to discuss opportunities for decay studies at the Californium Rare Isotope Breeder Upgrade (CARIBU) of the ATLAS facility with emphasis on advanced fuel cycle (AFC) applications, nuclear structure and astrophysics research. The workshop will consist of review and contributed talks. Presentations by members of the local groups, outlining the status of relevant in-house projects and availabile equipment, will also be organized. time will also be set aside to discuss and develop working collaborations for future decay studies at CARIBU. Topics of interest include: (1) Decay data of relevance to AFC applications with emphasis on reactor decay heat; (2) Discrete high-resolution gamma-ray spectroscopy following radioactive decya and related topics; (3) Calorimetric studies of neutron-rich fission framgents using Total ABsorption Gamma-Ray Spectrometry (TAGS) technique; (4) Beta-delayed neutron emissions and related topics; and (5) Decay data needs for nuclear astrophysics.

  1. Time-of-flight mass spectrometry with desorption-ionization multiprobes (UV photons and KeV and MeV particles). Cluster atoms are used as projectiles

    International Nuclear Information System (INIS)

    Brunelle, A.

    1990-09-01

    A new time-of-flight mass spectrometer, Super-Depil, is used to study secondary ion emission from solid surfaces bombarded by various kinds of primary particles. Three different desorption probes were set up on this machine: a 252 californium source, providing by spontaneous fission about 1 MeV/u energy heavy ions, a 5 to 30 keV energy pulsed caesium ion gun and a pulsed nitrogen laser, which wavelength is 337 mm. A two stages electrostatic mirror was added to the spectrometer. The time spread due to the initial kinetic energy of secondary ions leaving the surface was minimized. The mass resolution is greater than 5000. The analysis of glycosidic terpenes showed the complementarity of the three probes. The study of such metastable ions, with the electrostatic mirror, showed that some fragment ions may conserve the memory of the stereochemistry of the neutral lost. Clusters ions were used as projectiles in the energy range 5-60 keV. A strong non linear enhancement was observed in the secondary ion yield from various targets [fr

  2. Peculiarities of extraction of carbonate complexes of trivalent transplutonium elements by alkylpyrocatechins

    International Nuclear Information System (INIS)

    Karalova, Z.K.; Bukina, T.I.; Myasoedov, B.F.; Fedorov, L.A.; Sokolovskij, S.A.

    1987-01-01

    Extraction of trivalent americium, curium, californium and europium by technical mixture of mono- and didecylpyrocatechin (TAP) in various diluents from carbonate solutions is investigated. Effect of many factors (pH, K 2 CO 3 concentration, TAP, metal; the time of phase contact) on the completeness of element isolation and separation is clarified. It is ascertained that the elements listed are quantitatively extracted by TAP solution in toluene and cyclohexane in the range of K 2 CO 3 concentrations from 0.25 to 1.5 mol/l. The difference in americium and curium distribution coefficient during their extraction by TAP from 0.25 mol/l of K 2 CO 3 solution is detected. Separation coefficients of the pair increase with the increase of carbonate solution pH. The separation can be improved at the stage of element reextraction by the mixture of K 2 CO 3 and DTPA or EDTA from alkylpyrocatechin, sunce rate constants of americium and curium reextraction differ greatly. Using 13 C NMR the composition of compounds in organic phase on the basis of 4-(α, α-dioctylethyl)pyrocatechin is investigated

  3. Fast neutron tomography with real-time pulse-shape discrimination in organic scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Joyce, Malcolm J., E-mail: m.joyce@lancaster.ac.uk [Department of Engineering, Lancaster University, Lancaster, Lancashire LA1 4YW (United Kingdom); Agar, Stewart [Department of Engineering, Lancaster University, Lancaster, Lancashire LA1 4YW (United Kingdom); Aspinall, Michael D. [Hybrid Instruments Ltd., Gordon Manley Building, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YW (United Kingdom); Beaumont, Jonathan S.; Colley, Edmund; Colling, Miriam; Dykes, Joseph; Kardasopoulos, Phoevos; Mitton, Katie [Department of Engineering, Lancaster University, Lancaster, Lancashire LA1 4YW (United Kingdom)

    2016-10-21

    A fast neutron tomography system based on the use of real-time pulse-shape discrimination in 7 organic liquid scintillation detectors is described. The system has been tested with a californium-252 source of dose rate 163 μSv/h at 1 m and neutron emission rate of 1.5×10{sup 7} per second into 4π and a maximum acquisition time of 2 h, to characterize two 100×100×100 mm{sup 3} concrete samples. The first of these was a solid sample and the second has a vertical, cylindrical void. The experimental data, supported by simulations with both Monte Carlo methods and MATLAB®, indicate that the presence of the internal cylindrical void, corners and inhomogeneities in the samples can be discerned. The potential for fast neutron assay of this type with the capability to probe hydrogenous features in large low-Z samples is discussed. Neutron tomography of bulk porous samples is achieved that combines effective penetration not possible with thermal neutrons in the absence of beam hardening.

  4. [Fast neutron cross section measurements]: Progress report

    International Nuclear Information System (INIS)

    1988-01-01

    As projected in our previous proposal, the past year on the cross section project at the University of Michigan has been one primarily of construction and assembly of our 14 MeV pulsed Neutron Facility. All the components of the system have now been either purchased or fabricated in our shop facilities and have been assembled in their final configuration. We are now in the process of testing the rf components that have been designed to deliver voltage to both the pulser and buncher stages. We expect that the system will be operational by the end of the current contract year. We have also accomplished the design and construction of several other major pieces of equipment that are needed to begin fast neutron time-of-flight measurements. These include the primary proton recoil detector, and a californium fission chamber needed in the efficiency calibration of the primary detector. We have also added considerable concrete shielding designed to lower the neutron background in the experimental area. 10 figs., 5 tabs

  5. Estimation of the sub-criticality of the sodium-cooled fast reactor Monju using the modified neutron source multiplication method

    International Nuclear Information System (INIS)

    Truchet, G.; Van Rooijen, W. F. G.; Shimazu, Y.; Yamaguchi, K.

    2012-01-01

    The Modified Neutron Source Method (MNSM) is applied to the Monju reactor. This static method to estimate sub-criticality has already given good results on commercial Pressurized Water Reactors. The MNSM consists both in the extraction of the fundamental mode seen by a detector to avoid the effect of higher modes near sources, and the correction of flux distortion effects due to control rod movement. Among Monju's particularities that have a big influence on MNSM factors are: the presence of two californium sources and the position of the detector which is located far from the core outside of the reactor vessel. The importance of spontaneous fission and (α, n) reactions which have increased during the shutdown period of 15 years will also be discussed. The relative position of detectors and sources deeply affect the correction factors in some regions. In order to evaluate the detector count rate, an analytical propagation has been conducted from the reactor vessel. For two subcritical states, an estimation of the reactivity has been made and compared to experimental data obtained in the restart experiments at Monju (2010). (authors)

  6. Measurement of neutron dose and spectra at light-water reactors

    International Nuclear Information System (INIS)

    Soldat, K.L.; Endres, G.W.R.; Cummings, F.M.

    1982-08-01

    In choosing one dosimeter over another, both sensitivity and precision must be addressed. It has been determined that dosimeters employing NTA film lack adequate sensitivity for use inside containment of nuclear plants. From this study, it is apparent that CR-39 and polycarbonate track etch films used without radiators are also inadequate. The rest of the dosimeters tested displayed adequate sensitivity. The two general types of dosimeters which comprise that group are: (1) TLDs and (2) the polycarbonate track etch which was used in conjunction with (n, α) radiators. The precision of the TLD dosimeter depends on the calibration technique and response correction technique. TLD dosimeters calibrated to D 2 O-moderated californium-252 or corrected based on 9- to 3-in. sphere response rates seemed to function best inside reactor containment. Polycarbonate track etch film with (n, α) radiators was found to be sensitive enough for use inside reactor containment; however, the standard deviation for the results was roughly twice the value of the most precise TLD albedo dosimeters. Also, several of the polycarbonate dosimeters saturated, rendering any evaluation impossible

  7. Development of an analytical theory to describe the PNAR and CIPN nondestructive assay techniques

    International Nuclear Information System (INIS)

    Bolind, Alan Michael

    2014-01-01

    Highlights: • Neutron albedo is modeled by a discrete and iterative reflection process. • The theory enables the PNAR and CIPN NDA techniques to be compared quantitatively. • Improvements to the data analysis and to the CIPN instrument design are suggested. • A correction to translate real no-reflection PNAR data into ideal data is provided. - Abstract: This paper develops an analytical theory to describe how neutron albedo (reflection) increases the multiplication of neutrons by a used fuel assembly. With this theory, the two nondestructive assay (NDA) techniques of Passive Neutron Albedo Reactivity (PNAR) and Californium-252 Interrogation with Prompt Neutron Detection (CIPN) can be compared directly. Specifically, the theory derives expressions for the PNAR and CIPN metrics in terms of the physical properties of the used fuel assembly, such as the neutron multiplications and fate probabilities. The theory thus clarifies the interpretation of these two NDA techniques and suggests ways to improve both the design of the NDA instruments and the algorithms for analyzing the measurement results

  8. Robotics at Savannah River site: activity report

    International Nuclear Information System (INIS)

    Byrd, J.S.

    1984-09-01

    The objectives of the Robotics Technology Group at the Savannah River Laboratory are to employ modern industrial robots and to develop unique automation and robotic systems to enhance process operations at the Savannah River site (SRP and SRL). The incentives are to improve safety, reduce personnel radiation exposure, improve product quality and productivity, and to reduce operating costs. During the past year robotic systems have been installed to fill chemical dilution vials in a SRP laboratory at 772-F and remove radioactive waste materials in the SRL Californium Production Facility at 773-A. A robotic system to lubricate an extrusion press has been developed and demonstrated in the SRL robotics laboratory and is scheduled for installation at the 321-M fuel fabrication area. A mobile robot was employed by SRP for a radiation monitoring task at a waste tank top in H-Area. Several other robots are installed in the SRL robotics laboratories and application development programs are underway. The status of these applications is presented in this report

  9. Efficiency of interaction between various radiation and chemicals

    International Nuclear Information System (INIS)

    Kim, Jin Kyu; Song, H. S.; Kim, J. S.; Chun, K. J.; Lee, Y. K.; Lee, B. H.; Shin, H. S.; Lee, K. H.; Petin, Vladislav G.

    2002-01-01

    KAERI and INP (Poland) have been carried out parallel study and joint experiments on the major topics according to MOU about their cooperative project. Major experimental techniques were TSH assay, comet assay, and synergism assay. The research consisted of the following workscopes. 1) Application of TSH bioindicator for studying the biological efficiency of radiation, 2) Relative biological efficiency of californium-252 neutrons in the induction of gene and lethal mutations in TSH cells normal and enriched with boron compound, 3) Effect of pesticide on radiation-induced mutations in TSH cells, 4) Interaction of radiation with pesticide on DNA damage in human peripheral blood lymphocytes, 5) Radiomodifying effect of boron and gadolinium compounds in human peripheral blood lymphocytes, 6) Mathematical description of synergistic interactions, 7) General regularities of synergistic interactions, and 8) Determinant of synergistic interaction between radiation, heat and chemicals in cell killing. Both institutes have established wide variety of research techniques applicable to various radiation research through the cooperation. The results of research can make the role of fundamental basis for the better relationship between Korea and Poland

  10. Separation of Am-Cm from Al(NO3)3 waste solutions by in-canyon-tank precipitation as oxalates

    International Nuclear Information System (INIS)

    Gray, L.W.; Burney, G.A.; Wilson, T.W.; McKibben, J.M.; Bibler, N.E.; Holtzscheiter, E.W.; Campbell, T.G.

    1982-04-01

    A process for recovery of Am-Cm residues from high-activity waste concentrates has been developed specifically for application in Savannah River Plant (SRP) canyon tanks. The Am-Cm residues were collected from a campaign to produce plutonium containing high isotopic concentrations of 242 Pu. The separation of Am-Cm from the high-activity waste stream, containing about 2M Al(NO 3 ) 3 , is necessary to produce an acceptable feed solution for a later pressurized cation exchange chromatography separation and purification step. The new process includes formic acid denitration, adjustment of contaminating cations by evaporation and water dilution, and oxalate precipitation of the actinides and lanthanides. After washing, the precipitate was dissolved in 8M nitric acid and the oxalate was destroyed by nitric acid oxidation that was catalyzed by manganous ions. This new process generates about one-fourth the waste of the californium solvent extraction process, which it replaced. The new process also produces a cleaner feed solution for the pressurized cation exchange chromatography separation and purification step

  11. Fabrication of intense neutron sources for medical applications

    International Nuclear Information System (INIS)

    Boulogne, A.R.; Walker, V.W.

    1975-01-01

    Simulated sources containing 252 Cf equivalents of 0.1 to 1.0 milligrams were prepared. Samarium was used as the simulant in a modified chemical plating technique similar to that used to prepare palladium-californium oxide cermet for industrial applications. The length of the platinum-10 percent iridium doubly encapsulated source with its protective sheath is 0.545 in. (14.1 mm). Outside dia of the source, including its sheath, is 0.109 in. (2.8 mm). Existing ''Brachytrons'' can accommodate this source form. This capsule system will withstand internal gas pressures from helium due to alpha decay and fission gases from a 1 mg 252 Cf source after ten years if the source is subjected to a maximum temperature of 800 0 C, the theoretical temperature of an accidental fire. Under these conditions the safety factor is 3. The capsule system is being tested with tracer amounts of 252 Cf to ensure that it will withstand adverse service conditions as well as tests specified for Special Form Materials. (auth)

  12. 4π-spectrometer technique for measurements of secondary neutron average number in nuclear fission by 252Cf neutrons

    International Nuclear Information System (INIS)

    Vasil'ev, Yu.A.; Barashkov, Yu.A.; Golovanov, O.A.; Sidorov, L.V.

    1977-01-01

    A method for determining the average number of secondary neutrons anti ν produced in nuclear fission by the neutrons of the 252 Cf fission spectra by means of a 4π time-of-flight spectrometer is described. Layers of 252 Cf and an isotope studied are placed close to each other; if the isotope layer density is 1 mg/cm 2 probability of its fission is about 10 -5 per one spontaneous fission of californium. Fission fragments of 252 Cf and the isotope investigated have been detected by two surface-barrier counters with an efficiency close to 100%. The layers and the counters are situated in a measuring chamber placed in the center of the 4π time-of-flight spectrometer. The latter is utilized as a neutron counter because of its fast response. The method has been verified by carrying out measurements for 235 U and 239 Pu. A comparison of the experimental and calculated results shows that the method suggested can apply to determine the number of secondary neutrons in fission of isotopes that have not been investigated yet

  13. B(E2) ↑ (01+ -> 21+) predictions for even–even nuclei in the differential equation model

    International Nuclear Information System (INIS)

    Nayak, R.C.; Pattnaik, S.

    2015-01-01

    We use the recently developed differential equation model (DEM) for the reduced electric quadrupole transition probability B(E2)↑ for the transition from the ground to the first 2 + state for predicting its values for a wide range of even–even nuclides almost throughout the nuclear landscape from Neon to Californium. This is made possible as the principal equation in the model, namely, the differential equation connecting the B(E2)↑ value of a given even–even nucleus with its derivatives with respect to the neutron and proton numbers, provides two different recursion relations, each connecting three different neighboring even–even nuclei from lower- to higher-mass numbers and vice versa. These relations are primarily responsible in extrapolating from known to unknown terrain of the B(E2)↑-landscape and thereby facilitate the predictions throughout. As a result, we have succeeded in predicting its hitherto unknown value for the adjacent 251 isotopes lying on either side of the known B(E2)↑ database. (author)

  14. Reprocessing of nuclear fuels at the Savannah River Plant

    International Nuclear Information System (INIS)

    Gray, L.W.

    1986-01-01

    For more than 30 years, the Savannah River Plant (SRP) has been a major supplier of nuclear materials such as plutonium-239 and tritium-3 for nuclear and thermonuclear weapons, plutonium-238 for space exploration, and isotopes of americium, curium, and californium for use in the nuclear research community. SRP is a complete nuclear park, providing most of the processes in the nuclear fuel cycle. Key processes involve fabrication and cladding of the nuclear fuel, target, and control assemblies; rework of heavy water for use as reactor moderator; reactor loading, operation, and unloading; chemical recovery of the reactor transmutation products and spent fuels; and management of the gaseous, liquid, and solid nuclear and chemical wastes; plus a host of support operations. The site's history and the key processes from fabrication of reactor fuels and targets to finishing of virgin plutonium for use in the nuclear weapons complex are reviewed. Emphasis has been given to the chemistry of the recovery and purification of weapons grade plutonium from irradiated reactor targets

  15. Test and evaluation of infrared detectors and arrays; Proceedings of the Meeting, Orlando, FL, Mar. 27-29, 1989

    Science.gov (United States)

    Hoke, Forney M.

    Papers on the testing and evaluation of IR detectors and arrays are presented, covering topics such as a short wavelength IR test system, pulse height analysis, the use of an expert system for IR detector testing, low-background IR focal plane testing, electron beam testing, high performance silicide Schottky photodiodes, the SDI organization focal plane test program, the absorption cross section of arsenic in silicon, and long wavelength IR hybrids. Other topics include low background radiometric detector measurements, an ultralow background dewar for IR detector characterization studies, a computer assisted mosaic array test station, a configurable detector array test station, automated detector material characterization capabilities, and a test system for mercury cadmium telluride photoconductor arrays. Additional topics include ionization dosimetry measurements inside a dewar for linac electron and californium-252 neutron environments, a radiation test facility using a variable-flux electron beam source, automated visual inspection of IR focal plane arrays, a titanium cryostat for low temperature radiation effects studies, a low dose rate gamma test facility, and the test and evaluation of stability in IR staring focal plane arrays after nonuniformity correction.

  16. Branching ratios of α-decay to ground and excited states of Fm, Cf, Cm and Pu

    Science.gov (United States)

    Hassanabadi, H.; Hosseini, S. S.

    2018-06-01

    We use the well-known Wentzel-Kramers-Brillouin (WKB) barrier penetration probability to calculate α-decay branching ratios for ground and excited states of heavy even-even nuclei of Fermium (248-254Fm), Californium (244-252Cf), Curium (238-248Cm) and Plutonium (234-244Pu) with 94 ≤Zp ≤100. We obtained the branching ratios for the excited states of daughter nucleus by the α-decay energy (Qα), the angular momentum of α-particle (ℓα), and the excitation probability of the daughter nucleus with the excitation energy of state ℓ in the daughter nucleus (i.e. Eℓ*). α-Decay half-lives have been evaluated by using the proximity potential model for the heavy even-even nuclei. We have reported the half-lives and compared the results with the experimental data. The theoretical branching ratios of α-transitions in our calculation are found to agree with the available experimental data well for 0+→ 0+, 0+→ 2+, 0+→ 4+, 0+→ 6+ and 0+ → 8+α-transitions.

  17. Dust vortices, clouds, and jets in nuclear-induced plasmas

    International Nuclear Information System (INIS)

    Vladimirov, V.I.; Deputatova, L.V.; Nefedov, A.P.; Fortov, V.E.; Rykov, V.A.; Khudyakov, A.V.

    2001-01-01

    The collective movement of dust particles in a plasma formed during deceleration of decay products of californium nuclei in neon is investigated experimentally. For the first time, compact vortex structures containing a large number of coagulating dust particles and dense dust clouds evolving in time are observed. Dust formations have clearly defined boundaries and particles in them form ordered liquid-type structures. Under steady-state conditions, dust structures exist from several minutes to hours. An increase in the voltage applied to the high-voltage electrode leads to the formation of dust particle jets. A change in the electric field configuration transforms the structures from one type to another. A strong recombination of electrons and ions at dust particles is observed. The momentum transfer from ions drifting in an external field to gas molecules is studied using the Monte Carlo method. It is shown that the transferred momentum is so large that it may cause a gas flow. The characteristic features of vortex flow in neon and in air are explained

  18. Glasses impregnated with lead for radiation shielding

    International Nuclear Information System (INIS)

    Abd El Monem, A.M.; Kansouh, W.A.; Megahid, R.M.; Ismail, A.L.; Awad, E.M.

    2005-01-01

    The attenuation properties of glasses with different concentration of lead have been investigated for the attenuation of gamma-rays from cesium-137 and for total gamma rays using a beam of neutrons and gamma rays emitted from californium-252 source. Measurements have been performed using a gamma-ray spectrometer with Nal(T1) detector for gamma-rays emitted from 137 Cs and a neutron/gamma spectrometer with stilbene scintillator for measurement of total gamma-rays from 252 Cf neutron source. The latter applied the pulse shape discrimination technique to distinguish between recoil proton and recoil electron pulses. The obtained results given the form displayed pulse height spectra and attenuation relations which were used to derive the linear attenuation coefficient (μ), and the mass attenuation coefficient (mu/p) of the investigated glasses. In addition, calculations were performed to determine the attenuation properties of glass shields under investigation using XCOM code given by the others. A comparison of the shielding properties of these glasses with some standard shielding materials indicated that, the investigated glasses process the shielding advantages required for different nuclear technology applications

  19. Calibration techniques and results for the Portsmouth Cf shuffler

    International Nuclear Information System (INIS)

    Gross, J.C.; Wines, K.M.

    1993-01-01

    As environmental concerns over radioactive waste disposal continue to rise, the importance of Californium shufflers as a versatile waste monitoring and segregation instrument also continue to increase. The extent to which different amounts and types of materials can be measured by the shuffler is directly related to the extent of its calibration. As shufflers become more common place and their waste management uses also rise, the importance of a wide ranging and thorough calibration becomes critical. This paper presents the techniques used at the Portsmouth Gaseous Diffusion Plant for calibrating the shuffler to detect levels of U-235 in radioactive waste. While the calibration techniques are similar to those used by Los Alamos, the standards that were used were constructed somewhat differently so that geometric effects are maximized. Also presented are shuffler transmission measurements that are used to determine the matrix type and the corresponding calibration. A discussion of the calibration data is given. This discussion includes specific aspects of the calibration such as overall range, high end limits, and poly shielding range and usefulness

  20. 48 CFR 252.237-7015 - Loss or damage (weight of articles).

    Science.gov (United States)

    2010-10-01

    ... shall— (1) Be liable for return of the articles furnished for service under this contract; and (2... in servicing the laundry is ____ percent of the weight recorded on delivery tickets when the laundry...

  1. 48 CFR 237.7204 - Format and clauses for educational service agreements.

    Science.gov (United States)

    2010-10-01

    ... order, official Government order, or other written communication). The (insert type of request, such as, delivery order, official Government order, or other written communication) will contain the number of this... completion. (j) “Curriculum” means a series of courses having a unified purpose and belonging primarily to...

  2. Standardized UXO Technology Demonstration Site, Blind Grid Scoring Record No. 237

    National Research Council Canada - National Science Library

    Overbay, Larry, Jr; Robitaille, George; Boutin, Matthew; Fling, Rick; McClung, Christina

    2005-01-01

    ...) utilizing the APG Standardized UXO Technology Demonstration Site Blind Grid. The scoring record was coordinated by Larry Overbay and the Standardized UXO Technology Demonstration Site Scoring Committee...

  3. 27 CFR 19.237 - Disapproval of bonds or consents of surety.

    Science.gov (United States)

    2010-04-01

    ..., prohibiting the manufacture, sale, importation, or transportation of spirits, wine, beer, or other... States, if such provision related to internal revenue or customs taxation of spirits, wines, or beer, or...

  4. 48 CFR 252.237-7000 - Notice of special standards of responsibility.

    Science.gov (United States)

    2010-10-01

    ..., of “Government Auditing Standards.” (1) Qualifications; (2) Independence; and (3) Quality Control. (b) “Government Auditing Standards” is issued by the Comptroller General of the United States and is available for... Contracting Officer evidence that it is licensed by the cognizant licensing authority in the state or other...

  5. 48 CFR 52.237-11 - Accepting and Dispensing of $1 Coin.

    Science.gov (United States)

    2010-10-01

    ... REGULATION (CONTINUED) CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and... premises owned by the United States or under the control of any agency or instrumentality of the United...

  6. In situ x-ray fluorescence and californium-252 neutron activation analysis for marine and terrestrial mineral exploration

    International Nuclear Information System (INIS)

    Wogman, N.A.

    1976-12-01

    Instrumentation has been designed for in situ analysis of marine and terrestrial minerals using the techniques of x-ray fluorescence and neutron activation analysis. The energy-dispersive x-ray fluorescence analyzer allows more than 20 elements to be quantitatively measured at the 10 ppM level in water depths to 300 m. The analyzer consists of a solid cryogen-cooled Si(Li) detector, a 50 mCi 109 Cd or 57 Co excitation source, and an analyzer-computer system for data storage and manipulation. The neutron activation analysis, which is designed to measure up to 30 elements at parts per hundred to ppM levels, utilizes the man-made element 252 Cf as its neutron activation source. The resulting radioelements which emit characteristic gamma radiation are then analyzed in situ during 2- to 200-s counting intervals with Ge(Li) or NaI(T1) detector systems. An extension of this latter technique, which uses a 252 Cf- 235 U fueled subcritical multiplier, is also being studied. The subcritical facility allows the neutrons from the 252 Cf source to be multiplied, thus providing greater neutron flux. Details of these in situ analysis systems, actual in situ spectra, and recorded data are discussed with respect to the detection of minerals at their varying concentration levels. The system response of each illustrates its usefulness for various rapid environmental mineral exploration studies. These techniques can be utilized on terrestrial surfaces and marine or fresh water sediments. 5 figures, 2 tables

  7. Coffee consumption and risk of incident gout in women: the Nurses' Health Study.

    Science.gov (United States)

    Choi, Hyon K; Curhan, Gary

    2010-10-01

    Coffee is one of the most widely consumed beverages in the world and may affect the risk of gout via various mechanisms, but prospective data on the relation between coffee intake and the risk of incident gout are limited. Over a 26-y period, we prospectively examined the relation between coffee intake and risk of incident gout in 89,433 female participants in the Nurses' Health Study. We assessed the consumption of coffee, decaffeinated coffee, tea, and total caffeine in participants every 2-4 y through validated questionnaires. We used a supplementary questionnaire to ascertain whether participants met the survey criteria of the American College of Rheumatology for gout. During the 26 y of follow-up, we documented 896 confirmed incident cases of gout. There was an inverse association between higher coffee intake and the risk of gout. The multivariate relative risks (RRs) for incident gout according to coffee-consumption categories [ie, 0, 1-237, 238-947, and ≥948 mL coffee/d (237 mL = one 8-ounce cup)] were 1.00, 0.97, 0.78 (95% CI: 0.64, 0.95), and 0.43 (95% CI: 0.30, 0.61; P for trend coffee, the multivariate RRs according to consumption categories (0, 1-237, and ≥237 mL decaffeinated coffee/d) were 1.00, 1.02, and 0.77 (95% CI: 0.63, 0.95; P for trend = 0.02), respectively. There was an inverse association between total caffeine from all sources and the risk of gout; the multivariate RR of the highest quintile compared with the lowest quintile was 0.52 (95% CI: 0.41, 0.68; P for trend coffee consumption is associated with a lower risk of incident gout in women.

  8. Experimental study on neptunium migration under in situ geochemical conditions

    Science.gov (United States)

    Kumata, M.; Vandergraaf, T. T.

    1998-12-01

    Results are reported for migration experiments performed with Np under in situ geochemical conditions over a range of groundwater flow rates in columns of crushed rock in a specially designed facility at the 240-level of the Underground Research Laboratory (URL) near Pinawa, Manitoba, Canada. This laboratory is situated in an intrusive granitic rock formation, the Lac du Bonnet batholith. Highly altered granitic rock and groundwater were obtained from a major subhorizontal fracture zone at a depth of 250 m in the URL. The granite was wet-crushed and wet-sieved with groundwater from this fracture zone. The 180-850-μm size fraction was selected and packed in 20-cm long, 2.54-cm in diameter Teflon™-lined stainless steel columns. Approximately 30-ml vols of groundwater containing 3HHO and 237Np were injected into the columns at flow rates of 0.3, 1, and 3 ml/h, followed by elution with groundwater, obtained from the subhorizontal fracture, at the same flow rates, for a period of 95 days. Elution profiles for 3HHO were obtained, but no 237Np was detected in the eluted groundwater. After terminating the migration experiments, the columns were frozen, the column material was removed and cut into twenty 1-cm thick sections and each section was analyzed by gamma spectrometry. Profiles of 237Np were obtained for the three columns. A one-dimensional transport model was fitted to the 3HHO breakthrough curves to obtain flow parameters for this experiment. These flow parameters were in turn applied to the 237Np concentration profiles in the columns to produce sorption and dispersion coefficients for Np. The results show a strong dependence of retardation factors ( Rf) on flow rate. The decrease in the retarded velocity of the neptunium ( Vn) varied over one order of magnitude under the geochemical conditions for these experiments.

  9. Partial neutron capture cross sections of actinides using cold neutron prompt gamma activation analysis

    International Nuclear Information System (INIS)

    Genreith, Christoph

    2015-01-01

    Nuclear waste needs to be characterized for its safe handling and storage. In particular long-lived actinides render the waste characterization challenging. The results described in this thesis demonstrate that Prompt Gamma Neutron Activation Analysis (PGAA) with cold neutrons is a reliable tool for the non-destructive analysis of actinides. Nuclear data required for an accurate identification and quantification of actinides was acquired. Therefore, a sample design suitable for accurate and precise measurements of prompt γ-ray energies and partial cross sections of long-lived actinides at existing PGAA facilities was presented. Using the developed sample design the fundamental prompt γ-ray data on 237 Np, 241 Am and 242 Pu were measured. The data were validated by repetitive analysis of different samples at two individual irradiation and counting facilities - the BRR in Budapest and the FRM II in Garching near Munich. Employing cold neutrons, resonance neutron capture by low energetic resonances was avoided during the experiments. This is an improvement over older neutron activation based works at thermal reactor neutron energies. 152 prompt γ-rays of 237 Np were identified, as well as 19 of 241 Am, and 127 prompt γ-rays of 242 Pu. In all cases, both high and lower energetic prompt γ-rays were identified. The most intense line of 237 Np was observed at an energy of E γ =182.82(10) keV associated with a partial capture cross section of σ γ =22.06(39) b. The most intense prompt γ-ray lines of 241 Am and of 242 Pu were observed at E γ =154.72(7) keV with σ γ =72.80(252) b and E γ =287.69(8) keV with σ γ =7.07(12) b, respectively. The measurements described in this thesis provide the first reported quantifications on partial radiative capture cross sections for 237 Np, 241 Am and 242 Pu measured simultaneously over the large energy range from 45 keV to 12 MeV. Detailed uncertainty assessments were performed and the validity of the given uncertainties was

  10. Study of extraction chromatography methods of separation of neptunium and its radiometric determination

    International Nuclear Information System (INIS)

    Reich, M.

    2009-04-01

    In presented dissertation thesis the separation procedure for determination of neptunium in model solutions and also in soil samples was designed. 1. The sorbent was prepared on basis of hydrophobised silica gel with silica oil for hydrophobisation - Lukooil H. Extraction agent was anchored on this modified surface -quarternary ammonium salt Aliquat 336. In experiments was proved, that sorbent prepared like this is resist enough to the elution solutions using in separation procedures. It was found out that maximal concentration of deposited Aliquat 336 in benzene on hydrophobised silica gel selected granulate size is 40%. Sorbent prepared with silica gel lower granulate size and also with higher concentration of Aliquat 336 in benzene became sticky and unsuitable for using in separation columns. 2. The prepared sorbent is similar to commercial produced TEVA resin made by company Eichrom and for purpose of this project it was cheaper but the same effective alternative in comparing to mentioned commercial resin. 3. The separation procedure for isolation of 237 Np from radionuclides interfering during its radiometric determination with alpha spectrometry was designed -in scientific publications hasn't been described yet. The procedure consists of using formic acid for reduction of radionuclides interfering by alpha spectrometric determination of 237 Np and subsequent purification of neptunium on the next column by using ferrous sulphamate as reduction agent. This procedure was applied to the model solutions and also to the soil samples. The model solutions and soil samples for these experiments were contaminated with known amounts of 237 Np, 238 pU, 232 Th and mixture of 234 U/ 238 U. The effective separation of neptunium from described radionuclides was achieved with application of the described separation procedure. 4. The separation procedure for separation of 239 Np from its mother radionuclide 241 Am was designed with prepared sorbent. Different washing and

  11. Fission fragment angular distributions and fission cross section validation

    International Nuclear Information System (INIS)

    Leong, Lou Sai

    2013-01-01

    The present knowledge of angular distributions of neutron-induced fission is limited to a maximal energy of 15 MeV, with large discrepancies around 14 MeV. Only 238 U and 232 Th have been investigated up to 100 MeV in a single experiment. The n-TOF Collaboration performed the fission cross section measurement of several actinides ( 232 Th, 235 U, 238 U, 234 U, 237 Np) at the n-TOF facility using an experimental set-up made of Parallel Plate Avalanche Counters (PPAC), extending the energy domain of the incident neutron above hundreds of MeV. The method based on the detection of the 2 fragments in coincidence allowed to clearly disentangle the fission reactions among other types of reactions occurring in the spallation domain. I will show the methods we used to reconstruct the full angular resolution by the tracking of fission fragments. Below 10 MeV our results are consistent with existing data. For example in the case of 232 Th, below 10 MeV the results show clearly the variation occurring at the first (1 MeV) and second (7 MeV) chance fission, corresponding to transition states of given J and K (total spin and its projection on the fission axis), and a much more accurate energy dependence at the 3. chance threshold (14 MeV) has been obtained. In the spallation domain, above 30 MeV we confirm the high anisotropy revealed in 232 Th by the single existing data set. I'll discuss the implications of this finding, related to the low anisotropy exhibited in proton-induced fission. I also explore the critical experiments which is valuable checks of nuclear data. The 237 Np neutron-induced fission cross section has recently been measured in a large energy range (from eV to GeV) at the n-TOF facility at CERN. When compared to previous measurements, the n-TOF fission cross section appears to be higher by 5-7 % beyond the fission threshold. To check the relevance of n-TOF data, we simulate a criticality experiment performed at Los Alamos with a 6 kg sphere of 237 Np. This

  12. Woods-Saxon potential parametrization at large deformations for plutonium odd isotopes

    International Nuclear Information System (INIS)

    Garcia, F.; Garrote, E.; Yoneama, M.L.; Arruda-Neto, J.D.T.; Mesa, J.; Bringas, F.; Likhachev, V.P.; Rodriguez, O.; Guzman, F.

    1999-01-01

    The structure of single-particle levels in the second minima of 237,239,241 Pu was analyzed with the help of an axially-deformed Woods-Saxon potential. The nuclear shape was parametrized in terms of the cassinian ovaloids. A parametrization of the spin-orbit part of the potential was obtained in the region corresponding to large deformations (second minimum), depending only on the nuclear surface area. With this parametrization, we were able to reproduce successfully the spin, parity and energies of the rotational band built on the 8 μ s isomeric state in 239 Pu and, also, a spin assignment for both isomeric states in 237 Pu and 241 Pu was carried out. (orig.)

  13. Nuclear data for innovative reactors having persistent resistance to nuclear proliferation

    International Nuclear Information System (INIS)

    Yoshida, Tadashi; Hagura, Naoto; Toshinsky, Vladimir; Saito, Masaki

    2005-01-01

    The Protected Plutonium Production (P 3 ) project has been initiated in order to realize the proliferation-resistant plutonium. The first stage of this project is based on the idea to protect plutonium by 238 Pu generated from 237 Np doped in the fresh uranium fuel. Along with the burnup going on, the doped 237 Np is transmuted via 238 Np to 238 Pu, which is the intense neutron source of spontaneous fission (2.6x10 3 n/g/s). These neutrons will deteriorate the quality of the plutonium as the nuclear explosive material. In addition, high alpha-decay heat of 238 Pu (560 W/kg) makes the processes of the explosive fabrication and its maintenance technologically difficult. In this background we surveyed the status of nuclear data relevant to the P 3 -concept reactor design. The reliability of the capture cross section data for 237 Np and 238 Pu are far from satisfactory and more accurate experiments and evaluations are required. As fissions in these nuclides do not always play any decisive role in the P 3 concept LWR, we can be fairly tolerable about the uncertainty of the fission cross section data, but further study is needed. (author)

  14. Measurement of fast neutron induced fission cross section of minor-actinide

    International Nuclear Information System (INIS)

    Hirakawa, Naohiro

    1997-03-01

    In fuel cycles with recycled actinide, core characteristics are largely influenced by minor actinide (MA: Np, Am, Cm). Accurate nuclear data of MA such as fission cross section are required to estimate the effect of MA with high accuracy. In this study, fast neutron induced fission cross section of MA is measured using Dynamitron Accelerator in Tohoku University. The experimental method and the samples, which were developed or introduced during the last year, were improved in this fiscal year: (1) Development of a sealed fission chamber, (2) Intensification of Li neutron target, (3) Improvement of time-resolution of Time-of-Flight (TOF) electronic circuit, (4) Introduction of Np237 samples with large sample mass and (5) Introduction of a U235 sample with high purity. Using these improved tools and samples, the fission cross section ratio of Np237 relative to U235 was measured between 5 to 100 keV, and the fission cross section of Np237 was deduced. On the other hand, samples of Am241 and Am243 were obtained from Japan Atomic Energy Research Institute (JAERI) after investigating fission cross section of two americium isotopes (Am241 and Am 243) which are important for core physics calculation of fast reactors. (author)

  15. Effect of time dependence of neutron flux on the plutonium 238 production

    International Nuclear Information System (INIS)

    Rudik, A.P.

    1975-01-01

    An analytical treatment is given of the dependence of a plutonium-238 yield when irradiating neptunium-237 on the time variation of the neutron flux. This dependence is governed by the two physical factors: the competition between the beta decay and the neptunium-238 depletion, and the differences in the depletion rate of neptunium-237, neptunium-238 and plutonium-238 with thermal and resonance neutrons. The role of the neptunium-238 nonprompt decay has been studied and the order of the effect determined, and it has been established that it is advantageous to irradiate neptunium-237 in the lowest central neutron flux possible for thermal and resonance neutron reactors. A perturbation theory has been developed to determine the role of the time variation of the thermal neutron flux and it has been established that, the integral neutron flux being the same, it is advantageous to irradiate the material in a drooping rather than a constant flux of neutrons. The simplest example of great time variations of a neutron flux has been considered and it has been established that in this particular case the conclusions made in the framework of the perturbation theory find a qualitative support. Convenient formulas are given for determining the number of neutrons used to produce plutonium-238

  16. 78 FR 73565 - Agency Information Collection Activities: Proposed Collection, Comments Requested, New Collection...

    Science.gov (United States)

    2013-12-06

    ..., homicide offenses, human trafficking, kidnapping/abduction, larceny/theft offenses, motor vehicle theft...; Public Law110-457, Title II, Section 237(a), (b), December 23, 2008, the William Wilberforce Trafficking...

  17. The Geochemical Behaviour of Tc, Np, and Pu in Spent Nuclear Fuel in an Oxidizing Environment

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Edgar C.; Hanson, Brady D.; McNamara, Bruce K.; R. Giere and P. Stille

    2004-10-01

    Studies at the Nopal and Shinkolowbwe uranium deposits show that the primary uraninite (UO2) altered to a suite of secondary uranyl minerals similar to those observed in corrosion tests with uranium oxide . Although the Nopal I deposit tells us something about the possible fate of uranium, it tells us little about the likely fate of the important long-lived radionuclides; iodine (129I), cesium (135Cs), technetium (99Tc), neptunium (237Np), and plutonium (239Pu). Most performance assessment (PA) models, assume conservatively, that as the UO2 matrix corrodes, the key radionuclides (129I, 99Tc, 237Np, and 239Pu) will be released congruently. In so doing, these PA models force increased reliance on human engineered barriers.

  18. The Geochemical Behavior of Tc, Np, and Pu in Spent Nuclear Fuel in an Oxidizing Environment

    International Nuclear Information System (INIS)

    Buck, Edgar C.; Hanson, Brady D.; McNamara, Bruce K.; R. Giere; P. Stille

    2004-01-01

    Studies at the Nopal and Shinkolowbwe uranium deposits show that the primary uraninite (UO2) altered to a suite of secondary uranyl minerals similar to those observed in corrosion tests with uranium oxide . Although the Nopal I deposit tells us something about the possible fate of uranium, it tells us little about the likely fate of the important long-lived radionuclides; iodine (129I), cesium (135Cs), technetium (99Tc), neptunium (237Np), and plutonium (239Pu). Most performance assessment (PA) models, assume conservatively, that as the UO2 matrix corrodes, the key radionuclides (129I, 99Tc, 237Np, and 239Pu) will be released congruently. In so doing, these PA models force increased reliance on human engineered barriers

  19. Woods-Saxon potential parametrization at large deformations for odd-plutonium nuclei

    International Nuclear Information System (INIS)

    Garcia, F.; Yoneama, M.L.; Arruda Neto, J.D.T.; Mesa, J.; Bringas, F.; Dias, J.F.; Likhachev, V.P.

    1997-01-01

    The structure of the the single-particle levels in the secondary minima of 237,239,241 Pu fissioning nuclei is analysed with the help of an axially-deformed Woods-Saxon potential. The nuclear shape was parametrized in terms of the Cassinian ovaloids. The parametrization of the spin-orbit part of the potential in the region corresponding to large deformations (second minimum), which depends only on the nuclear surface area, B s , was obtained. With this relation we were able to reproduce successfully the spin (parity) and the energies of the rotational band built on the 8μs isomeric rate in 239 Pu and also to make a spin assignment for both isomer states in 237 Pu and 241 Pu. (author)

  20. Contribution to the study of the influences of the excitation energy on the characteristics of the fission process

    International Nuclear Information System (INIS)

    Wagemans, C.

    1979-01-01

    Neutron induced and spontaneous fission with neutron energies from 10 -2 to 2.10 5 eV have been studied. Thermal neutron induced fission measurements in Pa 231 , Th 232 , Np 237 , U 233 , U 235 , Pu 239 and Pu 241 are reported. Energy and mass distributions of heavy fission fragments due to the spontaneous fission of Pu 240 are compared to the results obtained by thermal neutron fission of Pu 239 ; the events observed with U 236 , Pu 240 , Pa 232 and Np 238 are explained by the Bohr theory of fission channels. Ternary fission phenomena of U 233 , U 235 , Pu 239 , Pa 231 and Np 237 induced by thermal neutrons are explained and compared to models of Carjan and Feather. (MDC)