Experimental 233U nondestructive assay with a random driver

International Nuclear Information System (INIS)

Goris, P.

1979-01-01

Nondestructive assay (NDA) of 233 U in quantities up to 15 grams containing 7 ppM 232 U age 2 years was investigated with a random driver. A passive singles counting technique showed a reproducibility within 0.2% at the 95% confidence level. This technique would be applicable throughout a process in which all of the 233 U had the same 232 U content at the same age. Where the 232 U content varies, determination of 233 U fissile content would require active NDA. Active coincidence counting utilizing a 238 Pu, Li neutron source and a plastic scintillator detector system showed a reproducibility limit within 15% at the 95% confidence limit. The active technique was found to be very dependent on the detector system resolving time in order to make proper random coincidence corrections associated with the high gamma activity from the 232 U decay chain

History of Uranium-233(233U)Processing at the Rocky Flats Plant. In support of the RFETS Acceptable Knowledge Program

International Nuclear Information System (INIS)

Moment, R.L.; Gibbs, F.E.; Freiboth, C.J.

1999-01-01

This report documents the processing of Uranium-233 at the Rocky Flats Plant (Rocky Flats Environmental Technology Site). The information may be used to meet Waste Isolation Pilot Plant (WIPP) Waste Acceptance Criteria (WAC)and for determining potential Uranium-233 content in applicable residue waste streams

Fast and thermal data testing of 233U critical assemblies

International Nuclear Information System (INIS)

Wright, R.Q.; Jordan, W.C.; Leal, L.C.

1999-01-01

Many sources have been used to obtain 233 U benchmark descriptions. Unfortunately, some of these are not reliable since a thorough and complete benchmark evaluation often has not been done. For 24 yr a principal source for 233 U benchmarks has been the Cross Section Evaluation Working Group (CSEWG) Benchmark Specifications. The CSEWG specifications included only two fast benchmarks and three thermal benchmarks. The thermal benchmarks were H 2 O-moderated thorium-oxide exponential lattices. Since the thorium-oxide lattices were exponential experiments, they have not been widely used. CSEWG has also used the 233 U Oak Ridge National Laboratory (ORNL) spheres for many years. One advantage of the CSEWG fast benchmarks, JEZEBEL-23 and FLATTOP-23, is that experiments were done for central-reaction-rate ratios. These reaction-rate ratios provide very valuable information to data testers and evaluators that would not otherwise be available. In recent years the International Handbook of Evaluated Criticality Safety Benchmark Experiments has, in general, been a very useful and reliable source. The Handbook does not include central-reaction-rate ratio experiments, however. A new set of 233 U benchmark experiments has been added to the most recent release of the Handbook, U233-SOL-THERM-004. These are paraffin-reflected cylinders of 233 U uranyl-nitrate solutions. Unfortunately, the estimated benchmark uncertainties are on the order of 0.9 to 1.0% in k eff . Benchmark testing has been done for some of these U233-SOL-THERM-004 experiments. The authors have also discovered that the benchmark specifications for the Thomas uranyl-nitrate experiments given in Ref. 5 are incorrect. One problem with the Ref. 5 specifications is that the excess acid was not included. As part of this work, the authors developed revised specifications that include an excess acid correlation based on information from the experimental logbook

Initial ORNL site assessment report on the storage of 233U

International Nuclear Information System (INIS)

Bereolos, P.J.; Yong, L.K.; Sadlowe, A.R.; Ramey, D.W.; Krichinsky, A.M.

1998-03-01

The 233 U storage facility at ORNL is Building 3019. The inventory stored in Building 3019 consists of 426.5 kg of 233 U contained in 1,387.1 kg of total uranium. The inventory is primarily in the form of uranium oxides; however, uranium metal and other compounds are also stored. Over 99% of the inventory is contained in 1,007 packages stored in tube vaults within the facility. A tank of thorium nitrate solution, the P-24 Tank, contains 0.13 kg of 233 U in ∼ 4,000 gal. of solution. The facility is receiving additional 233 U for storage from the remediation of the Molten Salt Reactor Experiment (MSRE) at ORNL. Consolidation of material from sites with small holdings is also adding to the 233 U inventory. Additionally, small quantities ( 233 U are in other research facilities at ORNL. A risk assessment process was chosen to evaluate the stored material and packages based on available package records. The risk scenario was considered the failure of a package (or a group of similar packages) in the Building 3019 inventory. The probability of such a failure depends on packaging factors such as the age and material of construction of the containers. The consequence of such a failure depends on the amount and form of the material within the packages. One thousand seven packages were categorized with this methodology resulting in 859 low-risk packages, 147 medium-risk packages, and 1 high-risk package. This initial assessment also documents the status of the evaluation of the Building 3019 and its systems for safe storage of 233 U. The final assessment report for ORNL storage of 233 U is scheduled for June 1999. The report will document the facility assessments, the specific package inspection plan, and the results of initial package inspections

Isotopic dilution requirements for 233U criticality safety in processing and disposal facilities

International Nuclear Information System (INIS)

Elam, K.R.; Forsberg, C.W.; Hopper, C.M.; Wright, R.Q.

1997-11-01

The disposal of excess 233 U as waste is being considered. Because 233 U is a fissile material, one of the key requirements for processing 233 U to a final waste form and disposing of it is to avoid nuclear criticality. For many processing and disposal options, isotopic dilution is the most feasible and preferred option to avoid nuclear criticality. Isotopic dilution is dilution of fissile 233 U with nonfissile 238 U. The use of isotopic dilution removes any need to control nuclear criticality in process or disposal facilities through geometry or chemical composition. Isotopic dilution allows the use of existing waste management facilities, that are not designed for significant quantities of fissile materials, to be used for processing and disposing of 233 U. The amount of isotopic dilution required to reduce criticality concerns to reasonable levels was determined in this study to be ∼ 0.66 wt% 233 U. The numerical calculations used to define this limit consisted of a homogeneous system of silicon dioxide (SiO 2 ), water (H 2 O), 233 U, and depleted uranium (DU) in which the ratio of each component was varied to determine the conditions of maximum nuclear reactivity. About 188 parts of DU (0.2 wt% 235 U) are required to dilute 1 part of 233 U to this limit in a water-moderated system with no SiO 2 present. Thus, for the US inventory of 233 U, several hundred metric tons of DU would be required for isotopic dilution

Disposition of Uranium -233 (sup 233U) in Plutonium Metal and Oxide at the Rocky Flats Environmental Technology Site

International Nuclear Information System (INIS)

Freiboth, Cameron J.; Gibbs, Frank E.

2000-01-01

This report documents the position that the concentration of Uranium-233 ( 233 U) in plutonium metal and oxide currently stored at the DOE Rocky Flats Environmental Technology Site (RFETS) is well below the maximum permissible stabilization, packaging, shipping and storage limits. The 233 U stabilization, packaging and storage limit is 0.5 weight percent (wt%), which is also the shipping limit maximum. These two plutonium products (metal and oxide) are scheduled for processing through the Building 371 Plutonium Stabilization and Packaging System (PuSPS). This justification is supported by written technical reports, personnel interviews, and nuclear material inventories, as compiled in the ''History of Uranium-233 ( 233 U) Processing at the Rocky Flats Plant In Support of the RFETS Acceptable Knowledge Program'' RS-090-056, April 1, 1999. Relevant data from this report is summarized for application to the PuSPS metal and oxide processing campaigns

Th/U-233 multi-recycle in PWRs

International Nuclear Information System (INIS)

Yun, D.; Kim, T.K.; Taiwo, T.A.

2010-01-01

The use of thorium in current or advanced light water reactors (LWRs) has been of interest in recent years. These interests have been associated with the need to increase nuclear fuel resources and the perceived non-proliferation advantages of the utilization of thorium in the fuel cycle. Various options have been considered for the use of thorium in the LWR fuel cycle including: (1) its use in a once-through fuel cycle to replace non-fissile uranium or to extend fuel burnup due to its attractive fertile material conversion, (2) its use for fissile plutonium burning in limited recycle cores, and (3) its advantage in limiting the transuranic elements to be disposed off in a repository (if only Th/U-233 fuel is used). The possibility for thorium utilization in multirecycle system has also been considered by various researchers, primarily because of the potential for near breeders with Th/U-233 in the thermal energy range. The objective of this project is to evaluate the potential of the Th/U-233 fuel multirecycle in current LWRs, with focus this year on pressurized water reactors (PWRs). In this work, approaches for ensuring a sustainable multirecycle without the need for external source of makeup fissile material have been investigated. The intent is to achieve a design that allows existing PWRs to be used with minimal modifications. In all cases including homogeneous and heterogeneous assembly designs, the assembly pitch is kept consistent with that of the current PWRs (21.5 cm used). Because of design difficulties associated with using the same geometry and dimensions as a PWR core, the potential modifications (other than assembly pitch) that would be needed for PWRs to ensure a sustainable multirecycle system have been investigated and characterized. Additionally, the implications of the use of thorium on the LWR fuel cycle are discussed. In Section 2, background information on studies evaluating the use of thorium in the fuel cycle is provided, but focusing on

Th/U-233 multi-recycle in PWRs.

Energy Technology Data Exchange (ETDEWEB)

Yun, D.; Kim, T. K.; Taiwo, T. A.; Nuclear Engineering Division

2010-09-07

The use of thorium in current or advanced light water reactors (LWRs) has been of interest in recent years. These interests have been associated with the need to increase nuclear fuel resources and the perceived non-proliferation advantages of the utilization of thorium in the fuel cycle. Various options have been considered for the use of thorium in the LWR fuel cycle including: (1) its use in a once-through fuel cycle to replace non-fissile uranium or to extend fuel burnup due to its attractive fertile material conversion, (2) its use for fissile plutonium burning in limited recycle cores, and (3) its advantage in limiting the transuranic elements to be disposed off in a repository (if only Th/U-233 fuel is used). The possibility for thorium utilization in multirecycle system has also been considered by various researchers, primarily because of the potential for near breeders with Th/U-233 in the thermal energy range. The objective of this project is to evaluate the potential of the Th/U-233 fuel multirecycle in current LWRs, with focus this year on pressurized water reactors (PWRs). In this work, approaches for ensuring a sustainable multirecycle without the need for external source of makeup fissile material have been investigated. The intent is to achieve a design that allows existing PWRs to be used with minimal modifications. In all cases including homogeneous and heterogeneous assembly designs, the assembly pitch is kept consistent with that of the current PWRs (21.5 cm used). Because of design difficulties associated with using the same geometry and dimensions as a PWR core, the potential modifications (other than assembly pitch) that would be needed for PWRs to ensure a sustainable multirecycle system have been investigated and characterized. Additionally, the implications of the use of thorium on the LWR fuel cycle are discussed. In Section 2, background information on studies evaluating the use of thorium in the fuel cycle is provided, but focusing on

Criticality considerations for 233U fuels in an HTGR fuel refabrication facility

International Nuclear Information System (INIS)

McNeany, S.R.; Jenkins, J.D.

1978-01-01

Eleven 233 U solution critical assemblies spanning an H/ 233 U ratio range of 40 to 2000 and a bare metal 233 U assembly have been calculated with the ENDF/B-IV and Hansen-Roach cross sections. The results from these calculations are compared with the experimental results and with each other. An increasing disagreement between calculations with ENDF/B and Hansen-Roach data with decreasing H/ 233 U ratio was observed, indicative of large differences in their intermediate energy cross sections. The Hansen-Roach cross sections appeared to give reasonably good agreement with experiments over the whole range; whereas the ENDF/B calculations yielded high values for k/sub eff/ on assemblies of low moderation. It is concluded that serious problems exist in the ENDF/B-IV representation of the 233 U cross sections in the intermediate energy range and that further evaluation of this nuclide is warranted. In addition, it is recommended that an experimental program be undertaken to obtain 233 U criticality data at low H/ 233 U ratios for verification of generalized criticality safety guidelines. Part II of this report presents the results of criticality calculations on specific pieces of equipment required for HTGR fuel refabrication. In particular, fuel particle storage hoppers and resin carbonization furnaces are criticality safe up to 22.9 cm (9.0 in.) in diameter providing water or other hydrogenous moderators are excluded. In addition, no criticality problems arise due to accumulation of particles in the off-gas scrubber reservoirs provided reasonable administrative controls are exercised

Neutron inelastic-scattering cross sections of 232Th, 233U, 235U, 238U, 239Pu and 240Pu

International Nuclear Information System (INIS)

Smith, A.B.; Guenther, P.T.

1982-01-01

Differential-neutron-emission cross sections of 232 Th, 233 U, 235 U, 238 U, 239 Pu and 240 Pu are measured between approx. = 1.0 and 3.5 MeV with the angle and magnitude detail needed to provide angle-integrated emission cross sections to approx. 232 Th, 233 U, 235 U and 238 U inelastic-scattering values, poor agreement is observed for 240 Pu, and a serious discrepancy exists in the case of 239 Pu

Amster: a molten-salt reactor concept generating its own 233U and incinerating transuranium elements

International Nuclear Information System (INIS)

Lecarpentier, D.; Garzenne, C.; Vergnes, J.; Mouney, H.; Delpech, M.

2002-01-01

In the coming century, sustainable development of atomic energy will require the development of new types of reactors able to exceed the limits of the existing reactor types, be it in terms of optimum use of natural fuel resources, reduction in the production of long-lived radioactive waste, or economic competitiveness. Of the various candidates with the potential to meet these needs, molten-salt reactors are particularly attractive, in the light of the benefits they offer, arising from two fundamental features: - A liquid fuel does away with the constraints inherent in solid fuel, leading to a drastic simplification of the fuel cycle, in particular making in possible to carry out on-line pyrochemical reprocessing; - Thorium cycle and thermal spectrum breeding. The MSBR concept proposed by ORNL in the 1970's thus gave a breeding factor of 1.06, with a doubling time of about 25 years. However, given the tight neutron balance of the thorium cycle (the η of 233 U is about 2.3), MSBR performance is only possible if there are strict constraints set on the in-line reprocessing unit: all the 233 Pa must be removed from the core so that it can decay on the 233 U in no more than about ten days (or at least 15 tonnes of salt to be extracted from the core daily), and the absorbing fission products, in particular the rare earths, must be extracted in about fifty days. With the AMSTER MSR concept, which we initially developed for incinerating transuranium elements, we looked to reduce the mass of salt to be reprocessed in order to minimise the size and complexity of the reprocessing unit coupled to the reactor, and the quantity of transuranium elements sent for disposal, as this is directly proportional to the mass of salt reprocessed for extraction of the fission products. Given that breeding was not an absolute necessity, because the reactor can be started by incinerating the transuranium elements from the spent fuel assemblies of current reactors, or if necessary by loading

Interim assessment of the denatured 233U fuel cycle: feasibility and nonproliferation characteristics

International Nuclear Information System (INIS)

Abbott, L.S.; Bartine, D.E.; Burns, T.J.

1979-12-01

A fuel cycle that employs 233 U denatured with 238 U and mixed with thorium fertile material is examined with respect to its proliferation-resistance characteristics and its technical and economic feasibility. The rationale for considering the denatured 233 U fuel cycle is presented, and the impact of the denatured fuel on the performance of Light-Water Reactors, Spectral-Shift-Controlled Reactors, Gas-Cooled Reactors, Heavy-Water Reactors, and Fast Breeder Reactors is discussed. The scope of the R, D and D programs to commercialize these reactors and their associated fuel cycles is also summarized and the resource requirements and economics of denatured 233 U cycles are compared to those of the conventional Pu/U cycle. In addition, several nuclear power systems that employ denatured 233 U fuel and are based on the energy center concept are evaluated

233U breeding and neutron multiplying blankets for fusion reactors

International Nuclear Information System (INIS)

Cook, A.G.; Maniscalco, J.A.

1975-01-01

In this work, along with a previous paper three possible uses of 14-MeV deuterium--tritium fusion neutrons are investigated: energy production, neutron multiplication, and fissile-fuel breeding. The results presented include neutronic studies of fissioning and nonfissioning thorium systems, tritium breeding systems, various fuel options (UO 2 , UC, UC 2 , etc.), and uranium as well as refractory metal first-wall neutron-multiplying regions. A brief energy balance and an estimate of potential revenues for fusion devices are given to help illustrate the potentials of these designs

A study of sodium-cooled fast breeder reactor with thorium blanket for supply of U-233 to high temperature gas cooled reactor

International Nuclear Information System (INIS)

Yoshida, H.; Nishimura, H.; Osugi, T.

1978-08-01

Symbiotic energy system between fast breeder reactor and thermal reactor would have a potential merit for nuclear proliferation problem. And when using HTGR as the thermal reactor in the system, the energy system appears to be promising as an energy system self-sufficient in fuels, which can generate both electricity and high temperature process heat. In the system the fast breeder reactor has to supply sufficient amount of fissile plutonium to keep the reactor going, and also produce U-233 necessary to the associated U-233 fuelled process heat production HTGR. Three types of LMFBR concepts with thorium blanket, conventional homogeneous core LMFBR, and axial and radial parfait heterogeneous core LMFBRs, have been investigated to find out suitable configurations of LMFBR for supply of U-233 to the HTGR with relatively high conversion ratio of 0.85, in the symbiotic energy system between LMFBR and HTGR. The investigation on LMFBR has been made on fuel sufficiency of the system, inherent safety such as sodium-void and Doppler coefficients, and fuel cycle cost. The followings were revealed; (1) Conventional homogeneous core LMFBR with thorium radial blanket well satisfies the condition of fuel sufficiency, if adequate radial blanket thickness is chosen. However, the sodium-void coefficient and fuel cycle cost are inferior to the other concepts. (2) Axial parfait heterogeneous core LMFBR can be regarded as one of the best LMFBR concepts installed in the symbiotic energy system, from the viewpoints of fuel sufficiency, inherent safety and fuel cycle cost. However, further investigations should be needed on reliability and operationability of the concept. (3) Radial parfait heterogeneous core LMFBR seems inadequate as the LMFBR in the system, because the configurations based on this concept does not satisfy plutonium and U-233 breedings, simultaneously. This LMFBR concept, however, has excellent breeding performance in the internal radial blanket. So further

Interim assessment of the denatured 233U fuel cycle: feasibility and nonproliferation characteristics

International Nuclear Information System (INIS)

Abbott, L.S.; Bartine, D.E.; Burns, T.J.

1978-12-01

A fuel cycle that employs 233 U denatured with 238 U and mixed with thorium fertile material is examined with respect to its proliferation-resistance characteristics and its technical and economic feasibility. The rationale for considering the denatured 233 U fuel cycle is presented, and the impact of the denatured fuel on the performance of Light-Water Reactors, Spectral-Shift-Controlled Reactors, Gas-Cooled Reactors, Heavy-Water Reactors, and Fast Breeder Reactors is discussed. The scope of the R, D and D programs to commercialize these reactors and their associated fuel cycles is also summarized and the resource requirements and economics of denatured 233 U cycles are compared to those of the conventional Pu/U cycle. In addition, several nuclear power systems that employ denatured 233 U fuel and are based on the energy center concept are evaluated. Under this concept, dispersed power reactors fueled with denatured or low-enriched uranium fuel are supported by secure energy centers in which sensitive activities of the nuclear cycle are performed. These activities include 233 U production by Pu-fueled transmuters (thermal or fast reactors) and reprocessing. A summary chapter presents the most significant conclusions from the study and recommends areas for future work

Recovery of 233U from irradiated J rods - operating experience

International Nuclear Information System (INIS)

Lakshmanan, K.; Natarajan, D.; Muthukumar, M.; Halder, Surajit; Jayakrishnan, G.; Selvarasan, M.; Kuppusamy, V.; Ganesan, V.; Vijayakumar, V.

2000-01-01

The first campaign of reprocessing was completed in 1988 and 233 U was delivered for fabrication of fuel for KAMINI. After revamping the facility, the second campaign was started in Dec 1998 and has processed some of the high density thoria rods from CIRUS successfully. Currently the campaign is in progress and it is planned to process the irradiated thorium rods from Dhruva. Interim 23 process selective to 233 U is adopted for separation of uranium from thorium and fission products

Compilation of criticality data involving thorium or 233U and light water moderation

Energy Technology Data Exchange (ETDEWEB)

Gore, B.F.

1978-07-01

The literature has been searched for criticality data for light water moderated systems which contain thorium or /sup 233/U, and data found are compiled herein. They are from critical experiments, extrapolations, and exponential experiments performed with homogeneous solutions and metal spheres of /sup 233/U; with lattices of fuel rods containing highly enriched /sup 235/UO/sub 2/ - ThO/sub 2/ and /sup 233/UO/sub 2/ - ThO/sub 2/; and with arrays of cyclinders of /sup 233/U solutions. The extent of existing criticality data has been compared with that necessary to implement a thorium-based fuel cycle. No experiments have been performed with any solutions containing thorium. Neither do data exist for homogeneous /sup 233/U systems with H/U < 34, except for solid metal systems. Arrays of solution cylinders up to 3 x 3 x 3 have been studied. Data for solutions containing fixed or soluble poisons are very limited. All critical lattices using /sup 233/UO/sub 2/ - ThO/sub 2/ fuels (LWBR program) were zoned radially, and in most cases axially also. Only lattice experiments using /sup 235/UO/sub 2/ - ThO/sub 2/ fuels have been performed using a single fuel rod type. Critical lattices of /sup 235/UO/sub 2/ - ThO/sub 2/ rods poisoned with boron have been measured, but only exponential experiments have been performed using boron-poisoned lattices of /sup 233/UO/sub 2/ - ThO/sub 2/ rods. No criticality data exist for denatured fuels (containing significant amounts of /sup 238/U) in either solution or lattice configurations.

Interim assessment of the denatured /sup 233/U fuel cycle: feasibility and nonproliferation characteristics

Energy Technology Data Exchange (ETDEWEB)

Abbott, L.S.; Bartine, D.E.; Burns, T.J. (eds.)

1978-12-01

A fuel cycle that employs /sup 233/U denatured with /sup 238/U and mixed with thorium fertile material is examined with respect to its proliferation-resistance characteristics and its technical and economic feasibility. The rationale for considering the denatured /sup 233/U fuel cycle is presented, and the impact of the denatured fuel on the performance of Light-Water Reactors, Spectral-Shift-Controlled Reactors, Gas-Cooled Reactors, Heavy-Water Reactors, and Fast Breeder Reactors is discussed. The scope of the R, D and D programs to commercialize these reactors and their associated fuel cycles is also summarized and the resource requirements and economics of denatured /sup 233/U cycles are compared to those of the conventional Pu/U cycle. In addition, several nuclear power systems that employ denatured /sup 233/U fuel and are based on the energy center concept are evaluated. Under this concept, dispersed power reactors fueled with denatured or low-enriched uranium fuel are supported by secure energy centers in which sensitive activities of the nuclear cycle are performed. These activities include /sup 233/U production by Pu-fueled transmuters (thermal or fast reactors) and reprocessing. A summary chapter presents the most significant conclusions from the study and recommends areas for future work.

Criticality safety validation: Simple geometry, single unit 233U systems

International Nuclear Information System (INIS)

Putman, V.L.

1997-06-01

Typically used LMITCO criticality safety computational methods are evaluated for suitability when applied to INEEL 233 U systems which reasonably can be modeled as simple-geometry, single-unit systems. Sixty-seven critical experiments of uranium highly enriched in 233 U, including 57 aqueous solution, thermal-energy systems and 10 metal, fast-energy systems, were modeled. These experiments include 41 cylindrical and 26 spherical cores, and 41 reflected and 26 unreflected systems. No experiments were found for intermediate-neutron-energy ranges, or with interstitial non-hydrogenous materials typical of waste systems, mixed 233 U and plutonium, or reflectors such as steel, lead, or concrete. No simple geometry experiments were found with cubic or annular cores, or approximating infinite sea systems. Calculations were performed with various tools and methodologies. Nine cross-section libraries, based on ENDF/B-IV, -V, or -VI.2, or on Hansen-Roach source data, were used with cross-section processing methods of MCNP or SCALE. The k eff calculations were performed with neutral-particle transport and Monte Carlo methods of criticality codes DANT, MCNP 4A, and KENO Va

U-233 fuelled low critical mass solution reactor experiment PURNIMA II

International Nuclear Information System (INIS)

Srinivasan, M.; Chandramoleshwar, K.; Pasupathy, C.S.; Rasheed, K.K.; Subba Rao, K.

1987-01-01

A homogeneous U-233 uranyl nitrate solution fuelled BeO reflected, low critical mass reactor has been built at the Bhabha Atomic Research Centre, India. Christened PURNIMA II, the reactor was used for the study of the variation of critical mass as a function of fuel solution concentration to determine the minimum critical mass achievable for this geometry. Other experiments performed include the determination of temperature coefficient of reactivity, study of time behaviour of photoneutrons produced due to interaction between decaying U-233 fission product gammas and the beryllium reflector and reactor noise measurements. Besides being the only operational U-233 fuelled reactor at present, PURNIMA II also has the distinction of having attained the lowest critical mass of 397 g of fissile fuel for any operating reactor at the current time. The paper briefly describes the facility and gives an account of the experiments performed and results achieved. (author)

Integral benchmark test of JENDL-4.0 for U-233 systems with ICSBEP handbook

International Nuclear Information System (INIS)

Kuwagaki, Kazuki; Nagaya, Yasunobu

2017-03-01

The integral benchmark test of JENDL-4.0 for U-233 systems using the continuous-energy Monte Carlo code MVP was conducted. The previous benchmark test was performed only for U-233 thermal solution and fast metallic systems in the ICSBEP handbook. In this study, MVP input files were prepared for uninvestigated benchmark problems in the handbook including compound thermal systems (mainly lattice systems) and integral benchmark test was performed. The prediction accuracy of JENDL-4.0 was evaluated for effective multiplication factors (k eff 's) of the U-233 systems. As a result, a trend of underestimation was observed for all the categories of U-233 systems. In the benchmark test of ENDF/B-VII.1 for U-233 systems with the ICSBEP handbook, it is reported that a decreasing trend of calculated k eff values in association with a parameter ATFF (Above-Thermal Fission Fraction) is observed. The ATFF values were also calculated in this benchmark test of JENDL-4.0 and the same trend as ENDF/B-VII.1 was observed. A CD-ROM is attached as an appendix. (J.P.N.)

Investigation of tritium and 233U breeding in a fission-fusion hybrid reactor fuelling with ThO2

International Nuclear Information System (INIS)

Yildiz, K.; Sahin, S.; Sahin, H. M.; Acir, A.; Yalcin, S.; Altinok, T.; Bayrak, M.; Alkan, M.; Durukan, O.

2007-01-01

In the world, thorium reserves are three times more than natural Uranium reserves. It is planned in the near future that nuclear reactors will use thorium as a fuel. Thorium is not a fissile isotope because it doesn't make fission with thermal neutrons so it could be converted to 2 33U isotope which has very high quality fission cross-section with thermal neutrons. 2 33U isotope can be used in present LWRs as an enrichment fuel. In the fusion reactors, tritium is the most important fossil fuel. Because tritium is not natural isotope, it has to be produced in the reactor. The purpose of this work is to investigate the tritium and 2 33U breeding in a fission-fusion hybrid reactor fuelling with ThO 2 for Δt=10 days during a reactor operation period in five years. The neutronic analysis is performed on an experimental hybrid blanket geometry. In the center of the hybrid blanket, there is a line neutron source in a cylindrical cavity, which simulates the fusion plasma chamber where high energy neutrons (14.1 MeV) are produced. The conventional fusion reaction delivers the external neutron source for blankets following, 2 D + 3 T →? 4 He (3.5 MeV) + n (14.1 MeV). (1) The fuel zone made up of natural-ThO 2 fuel and it is cooled with different coolants. In this work, five different moderator materials, which are Li 2 BeF 4 , LiF-NaF-BeF 2 , Li 2 0Sn 8 0, natural Lithium and Li 1 7Pb 8 3, are used as coolants. The radial reflector, called tritium breeding zones, is made of different Lithium compounds and graphite in sandwich structure. In the work, eight different Lithium compounds were used as tritium breeders in the tritium breeding zones, which are Li 3 N, Li 2 O, Li 2 O 2 , Li 2 TiO 3 , Li 4 SiO 3 , Li 2 ZrO 3 , LiBr and LiH. Neutron transport calculations are conducted in spherical geometry with the help of SCALE4.4A SYSTEM by solving the Boltzmann transport equation with code CSAS and XSDRNPM, under consideration of unresolved and resolved resonances, in S 8 -P 3

Sources of neutronics data involving thorium of 233U and light water moderation

International Nuclear Information System (INIS)

Davenport, L.C.

1978-11-01

A literature search has been conducted to locate sources of neutronics data for light water moderated systems which contain thorium and/or uranium-233. It is concluded that insufficient data is currently available to validate neutronics design methods for licensing the 233 UO 2 -ThO 2 fuel cycle in light water reactors. A summary of the neutronics data sources found is reported in this document. These sources include critical and exponential experiments with lattices of fuel rods containing 233 U + Th or 235 U + Th. A few experiments using homogeneous aqueous solutions of 233 UO 2 (NO 3 ) 2 or 233 UO 2 F 2 are also included. The only critical lattice data using both 233 U and Th came from the LWBR program. All these experiments were zoned radially and in most cases axially also. Geometrically clean lattice critical data were measured for the CETR and TUPE programs. Both series used 235 UO 2 -ThO 2 pellets. A series of 21 exponential experiments using 3% 233 UO 2 - 97% ThO 2 fuel vibratory compacted to 92% of theoretical density in Zircaloy-2 tubing was performed at BNL using both unpoisoned and boric acid poisoned H 2 O moderator. For completeness, homogeneous systems are listed in which basic neutronics data have been measured. However, it is expected that most data concerning homogeneous systems will be applied to criticality safety problems rather than neutronics methods validation

Neutron data evaluation of 233U

International Nuclear Information System (INIS)

Maslov, V.M.; Tetereva, N.A.; Kagalenko, A.B.; Kornilov, N.V.; Baba, M.; Hasegawa, A.

2003-08-01

Consistent evaluation of 233 U measured data base is performed. Hauser-Feshbach- Moldauer theory, coupled channel model and double-humped fission barrier model are employed. Total, differential scattering, fission and (n,xn) data are calculated using fission cross section data description as a major constraint. The direct excitation of ground state is calculated within rigid rotator model. Average resonance parameters are provided, which reproduce evaluated cross sections in the range of 0.6-40.5 keV. (author)

Studies on the recovery of 233U from phosphate containing aqueous waste using DBDECMP as extractant

International Nuclear Information System (INIS)

Sagar, V.B.; Oak, M.S.; Pawar, S.M.; Sivaramakrishnan, C.K.; Patil, S.K.

1990-01-01

A method for the recovery and purification of 233 U from phosphate containing analytical waste is developed. Extraction studies with Di-butyl N,N-diethylcarbamoylmethylphosphonate (DBDECMP) in xylene were carried out to explore the feasibility of separation and purification of 233 U from such wastes. Based on the data obtained, optimum conditions for the recovery of 233 U are suggested. (author) 11 refs.; 1 fig.; 3 tabs

Final Oak Ridge National Laboratory Site Assessment Report on the Storage of 233U

International Nuclear Information System (INIS)

Bereolos, P.J.; Yong, L.K.

1999-01-01

This assessment characterizes the 233 U inventories and storage facility at Oak Ridge National Laboratory (ORNL). This assessment is a commitment in the U.S. Department of Energy (DOE) Implementation Plan (IP), ''Safe Storage of Uranium-233,'' in response to the Defense Nuclear Facilities Safety Board's Recommendation 97-1

High conversion Th-U{sup 233} fuel assembly for current generation of PWRs

Energy Technology Data Exchange (ETDEWEB)

Baldova, D.; Fridman, E. [Reactor Safety Div., Helmholtz-Zentrum Dresden-Rossendorf, POB 510119, Dresden, 01314 (Germany)

2012-07-01

This paper presents a preliminary design of a high conversion Th-U{sup 233} fuel assembly applicable for current generation of Pressurized Water Reactor (PWRs). The considered fuel assembly has a typical 17 x 17 PWR lattice. However in order to increase the conversion of Th{sup 232} to U{sup 233}, the assembly was subdivided into the two regions called seed and blanket. The central seed region has a higher than blanket U{sup 233} content and acts as a neutron source for the peripheral blanket region. The latest acts as a U{sup 233} breeder. While the seed fuel pins have a standard dimensions the blanket fuel radius was increased in order to reduce the moderation and to facilitate the resonance neutron absorption in blanket Th{sup 232}. The U{sup 233} content in the seed and blanket regions was optimized to achieve maximal initial to discharged fissile inventory ratio (FIR) taking into account the target fuel cycle length of 12 months with 3-batch reloading scheme. In this study the neutronic calculations were performed on the fuel assembly level using Helios deterministic lattice transport code. The fuel cycle length and the core k{sub eff} were estimated by applying the Non Linear Reactivity Model. The applicability of the HELIOS code for the analysis of the Th-based high conversion designs was confirmed with the help of continuous-energy Monte-Carlo code SERPENT. The results of optimization studies show that for the heterogeneous seed and blanket (SB) fuel assembly the FIR of about 0.95 can be achieved. (authors)

Resonance Region Covariance Analysis Method and New Covariance Data for Th-232, U-233, U-235, U-238, and Pu-239

International Nuclear Information System (INIS)

Leal, Luiz C.; Arbanas, Goran; Derrien, Herve; Wiarda, Dorothea

2008-01-01

Resonance-parameter covariance matrix (RPCM) evaluations in the resolved resonance region were done for 232Th, 233U, 235U, 238U, and 239Pu using the computer code SAMMY. The retroactive approach of the code SAMMY was used to generate the RPCMs for 233U, 235U. RPCMs for 232Th, 238U and 239Pu were generated together with the resonance parameter evaluations. The RPCMs were then converted in the ENDF format using the FILE32 representation. Alternatively, for computer storage reasons, the FILE32 was converted in the FILE33 cross section covariance matrix (CSCM). Both representations were processed using the computer code PUFF-IV. This paper describes the procedures used to generate the RPCM with SAMMY.

Criticality safety validation: Simple geometry, single unit {sup 233}U systems

Energy Technology Data Exchange (ETDEWEB)

Putman, V.L.

1997-06-01

Typically used LMITCO criticality safety computational methods are evaluated for suitability when applied to INEEL {sup 233}U systems which reasonably can be modeled as simple-geometry, single-unit systems. Sixty-seven critical experiments of uranium highly enriched in {sup 233}U, including 57 aqueous solution, thermal-energy systems and 10 metal, fast-energy systems, were modeled. These experiments include 41 cylindrical and 26 spherical cores, and 41 reflected and 26 unreflected systems. No experiments were found for intermediate-neutron-energy ranges, or with interstitial non-hydrogenous materials typical of waste systems, mixed {sup 233}U and plutonium, or reflectors such as steel, lead, or concrete. No simple geometry experiments were found with cubic or annular cores, or approximating infinite sea systems. Calculations were performed with various tools and methodologies. Nine cross-section libraries, based on ENDF/B-IV, -V, or -VI.2, or on Hansen-Roach source data, were used with cross-section processing methods of MCNP or SCALE. The k{sub eff} calculations were performed with neutral-particle transport and Monte Carlo methods of criticality codes DANT, MCNP 4A, and KENO Va.

14 CFR 23.3 - Airplane categories.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Airplane categories. 23.3 Section 23.3... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES General § 23.3 Airplane categories. (a) The normal category is limited to airplanes that have a seating configuration, excluding pilot...

Comparison of potential radiological impacts of 233U and 239Pu fuel cycles

International Nuclear Information System (INIS)

Meyer, H.R.; Little, C.A.; Witherspoon, J.P.; Till, J.E.

1979-01-01

Nuclear fuel cycles utilizing 233 U are currently the subject of considerable interest in the United States. This paper focuses on the identification of significant differences between the off-site radiological hazards posed by 232 Th/ 233 U (Th/U) and 238 U/ 239 Pu (U/Pu) fuel cycles, and represents a portion of our involvement in the Nonproliferation Alternative Systems Assessment Program (NASAP), to be used in support of the International Fuel Cycle Evaluation (INFCE). The major contributors to radiological dose are likely to be uranium mining and milling (58.5% of total fuel cycle dose), reprocessing (33.9%), and light-water reactor power generation (7.3%). The remainder of the cycle, including enrichment processes, fuel fabrication, transportation, and waste management, contributes only 0.3% to total estimated fuel cycle dose

A compact multi-plate fission chamber for the simultaneous measurement of 233U capture and fission cross-sections

Directory of Open Access Journals (Sweden)

Bacak M.

2017-01-01

Full Text Available 233U plays the essential role of fissile nucleus in the Th-U fuel cycle. A particularity of 233U is its small neutron capture cross-section which is about one order of magnitude lower than the fission cross-section on average. Therefore, the accuracy in the measurement of the 233U capture cross-section essentially relies on efficient capture-fission discrimination thus a combined setup of fission and γ-detectors is needed. At CERN n_TOF the Total Absorption Calorimeter (TAC coupled with compact fission detectors is used. Previously used MicroMegas (MGAS detectors showed significant γ-background issues above 100 eV coming from the copper mesh. A new measurement campaign of the 233U capture cross-section and alpha ratio is planned at the CERN n_TOF facility. For this measurement, a novel cylindrical multi ionization cell chamber was developed in order to provide a compact solution for 14 active targets read out by 8 anodes. Due to the high specific activity of 233U fast timing properties are required and achieved with the use of customized electronics and the very fast ionizing gas CF4 together with a high electric field strength. This paper describes the new fission chamber and the results of the first tests with neutrons at GELINA proving that it is suitable for the 233U measurement.

Breeding capability and void reactivity analysis of heavy-water-cooled thorium reactor

International Nuclear Information System (INIS)

Permana, Sidik; Takaki, Naoyuki; Sekimoto, Hiroshi

2008-01-01

The fuel breeding and void reactivity coefficient of thorium reactors have been investigated using heavy water as coolant for several parametric surveys on moderator-to-fuel ratio (MFR) and burnup. The equilibrium fuel cycle burnup calculation has been performed, which is coupled with the cell calculation for this evaluation. The η of 233 U shows its superiority over other fissile nuclides in the surveyed MFR ranges and always stays higher than 2.1, which indicates that the reactor has a breeding condition for a wide range of MFR. A breeding condition with a burnup comparable to that of a standard PWR or higher can be achieved by adopting a larger pin gap (1-6 mm), and a pin gap of about 2 mm can be used to achieve a breeding ratio (BR) of 1.1. A feasible design region of the reactors, which fulfills the breeding condition and negative void reactivity coefficient, has been found. A heavy-water-cooled PWR-type Th- 233 U fuel reactor can be designed as a breeder reactor with negative void coefficient. (author)

Assessment of the available {sup 233}U cross-section evaluations in the calculation of critical benchmark experiments

Energy Technology Data Exchange (ETDEWEB)

Leal, L.C.; Wright, R.Q.

1996-10-01

In this report we investigate the adequacy of the available {sup 233}U cross-section data for calculation of experimental critical systems. The {sup 233}U evaluations provided in two evaluated nuclear data libraries, the U.S. Data Bank [ENDF/B (Evaluated Nuclear Data Files)] and the Japanese Data Bank [JENDL (Japanese Evaluated Nuclear Data Library)] are examined. Calculations were performed for six thermal and ten fast experimental critical systems using the S{sub n} transport XSDRNPM code. To verify the performance of the {sup 233}U cross-section data for nuclear criticality safety application in which the neutron energy spectrum is predominantly in the epithermal energy range, calculations of four numerical benchmark systems with energy spectra in the intermediate energy range were done. These calculations serve only as an indication of the difference in calculated results that may be expected when the two {sup 233}U cross-section evaluations are used for problems with neutron spectra in the intermediate energy range. Additionally, comparisons of experimental and calculated central fission rate ratios were also made. The study has suggested that an ad hoc {sup 233}U evaluation based on the JENDL library provides better overall results for both fast and thermal experimental critical systems.

Assessment of the Available (Sup 233)U Cross Sections Evaluations in the Calculation of Critical Benchmark Experiments

Energy Technology Data Exchange (ETDEWEB)

Leal, L.C.

1993-01-01

In this report we investigate the adequacy of the available {sup 233}U cross-section data for calculation of experimental critical systems. The {sup 233}U evaluations provided in two evaluated nuclear data libraries, the U. S. Data Bank [ENDF/B (Evaluated Nuclear Data Files)] and the Japanese Data Bank [JENDL (Japanese Evaluated Nuclear Data Library)] are examined. Calculations were performed for six thermal and ten fast experimental critical systems using the Sn transport XSDRNPM code. To verify the performance of the {sup 233}U cross-section data for nuclear criticality safety application in which the neutron energy spectrum is predominantly in the epithermal energy range, calculations of four numerical benchmark systems with energy spectra in the intermediate energy range were done. These calculations serve only as an indication of the difference in calculated results that may be expected when the two {sup 233}U cross-section evaluations are used for problems with neutron spectra in the intermediate energy range. Additionally, comparisons of experimental and calculated central fission rate ratios were also made. The study has suggested that an ad hoc {sup 233}U evaluation based on the JENDL library provides better overall results for both fast and thermal experimental critical systems.

Subcritical multiplication measurements with a BeO reflected 233U uranyl nitrate solution system

International Nuclear Information System (INIS)

Job, P.K.; Srinivasan, M.; Nargundkar, V.R.; Chandramoleshwar, K.; Pasupathy, C.S.; Das, S.; Mayankutty, P.C.

1978-01-01

A series of subcritical multiplication measurements were carried out in PURNIMA with 233 U uranyl nitrate solution contained in all 11 x 11 cm 2 square sectional tank and reflected by 30 cm thickness of BeO on all sides. The objective of these experiments was to determine the 'Minimum critical mass' of the system in rectangular parellelopiped geometry. The rectangular aluminium core tank was attached to the bottom of an alpha tight glove box. BeO reflector was arranged below the glove box outside the core tank. The system multiplication was measured as a function of solution concentration and core volume by means of neutron detectors placed outside the assembly. The extrapolated critical mass was obtained through conventional inverse counts plot. The maximum amount of 233 U used was 120 gms. The rectangular geometry was estimated to be 235 +- 10 gms, in the concentration range of 80 to 120 gms/litre of 233 U. The experimental set up, procedure adopted, method of analysis and the details of the results are described. (author)

Evaluation of cross sections of Th-232 and U-233

International Nuclear Information System (INIS)

Dias, A.M.

1978-01-01

The cross sections in multigroups of Th-232 and U-233 are evaluated by comparison of theoretical results and experimental data obtained through experiments on the fast reactors IBR-I, EBR-II, BR-I and AETR. The deviation between calculated values and experimental results is about 10%. They are therefore satisfatory for neutronic calculations [pt

Fission Product Yields of 233U, 235U, 238U and 239Pu in Fields of Thermal Neutrons, Fission Neutrons and 14.7-MeV Neutrons

Science.gov (United States)

Laurec, J.; Adam, A.; de Bruyne, T.; Bauge, E.; Granier, T.; Aupiais, J.; Bersillon, O.; Le Petit, G.; Authier, N.; Casoli, P.

2010-12-01

The yields of more than fifteen fission products have been carefully measured using radiochemical techniques, for 235U(n,f), 239Pu(n,f) in a thermal spectrum, for 233U(n,f), 235U(n,f), and 239Pu(n,f) reactions in a fission neutron spectrum, and for 233U(n,f), 235U(n,f), 238U(n,f), and 239Pu(n,f) for 14.7 MeV monoenergetic neutrons. Irradiations were performed at the EL3 reactor, at the Caliban and Prospero critical assemblies, and at the Lancelot electrostatic accelerator in CEA-Valduc. Fissions were counted in thin deposits using fission ionization chambers. The number of fission products of each species were measured by gamma spectrometry of co-located thick deposits.

Preserving Ultra-Pure Uranium-233

International Nuclear Information System (INIS)

Krichinsky, Alan M.; Goldberg, Steven A.; Hutcheon, Ian D.

2011-01-01

Uranium-233 ( 233 U) is a synthetic isotope of uranium formed under reactor conditions during neutron capture by natural thorium ( 232 Th). At high purities, this synthetic isotope serves as a crucial reference material for accurately quantifying and characterizing uranium-bearing materials assays and isotopic distributions for domestic and international nuclear safeguards. Separated, high purity 233 U is stored in vaults at Oak Ridge National Laboratory (ORNL). These materials represent a broad spectrum of 233 U from the standpoint of isotopic purity - the purest being crucial for precise analyses in safeguarding uranium. All 233 U at ORNL is currently scheduled to be disposed of by down-blending with depleted uranium beginning in 2015. This will reduce safety concerns and security costs associated with storage. Down-blending this material will permanently destroy its potential value as a certified reference material for use in uranium analyses. Furthermore, no credible options exist for replacing 233 U due to the lack of operating production capability and the high cost of restarting currently shut down capabilities. A study was commissioned to determine the need for preserving high-purity 233 U. This study looked at the current supply and the historical and continuing domestic need for this crucial isotope. It examined the gap in supplies and uses to meet domestic needs and extrapolated them in the context of international safeguards and security activities - superimposed on the recognition that existing supplies are being depleted while candidate replacement material is being prepared for disposal. This study found that the total worldwide need by this projection is at least 850 g of certified 233 U reference material over the next 50 years. This amount also includes a strategic reserve. To meet this need, 18 individual items totaling 959 g of 233 U were identified as candidates for establishing a lasting supply of certified reference materials (CRM), all

Disposition Options for Uranium-233

International Nuclear Information System (INIS)

Beahm, E.C.; Dole, L.R.; Forsberg, C.W.; Icenhour, A.S.; Storch, S.N.

1999-01-01

The U.S. Department of Energy (DOE) Fissile Materials Disposition Program (MD), in support of the U.S. arms-control and nonproliferation policies, has initiated a program to disposition surplus weapons-usable fissile material by making it inaccessible and unattractive for use in nuclear weapons. Weapons-usable fissile materials include plutonium, high-enriched uranium (HEU), and uranium-233 (sup 233)U. In support of this program, Oak Ridge National Laboratory led DOE's contractor efforts to identify and characterize options for the long-term storage and disposal of excess (sup 233)U. Five storage and 17 disposal options were identified and are described herein

Studies on use of reflector material and its position within FBR core for reducing U{sup 232} content of U produced in ThO{sub 2} radial blankets

Energy Technology Data Exchange (ETDEWEB)

Sen, Sujoy, E-mail: sujoy@igcar.gov.in [Core Design Group, IGCAR, Kalpakkam (India); Prasad, Rajeev Ranjan; Bagchi, Subhrojit [Core Design Group, IGCAR, Kalpakkam (India); Mohanakrishnan, P. [MCNS, Manipal University, Manipal (India); Arul, A. John; Puthiyavinayagam, P. [Core Design Group, IGCAR, Kalpakkam (India)

2015-11-15

Highlights: • Nuclear data processing for multigroup neutron transport calculation. • Discrete ordinate and Monte Carlo neutron transport. • Breeding of Thorium in Fast Reactor. • Minimization of U{sup 232} in U{sup 233}. • Fuel burn up using Neutron Diffusion. - Abstract: Presence of U{sup 232} in U{sup 233} bred in thorium blanket of fast reactor is a major concern in fuel reprocessing. The former's daughter products being hard gamma emitter and the isotope itself having substantial half life, its presence beyond 10 ppm makes fuel recycle complicated and expensive. In this study possibility of decreasing U{sup 232} production in a typical FBR blanket by means of spectrum modification is examined. SS, depleted B{sub 4}C, SiC, Mo and W regions were introduced between core and radial blanket and evolution of isotopes were studied to arrive at an optimal configuration that satisfies requirements of breeding U{sup 233} and lowering U{sup 232}concentration. SS, B{sub 4}C, SiC, Mo and W are known to be high temperature material with appropriate stability in harsh fast reactor environment. Study has shown that introducing two SS reflector rows can achieve the required low value of U{sup 232}concentration without greatly compromising the U{sup 233}production.

Review of thorium-U233 cycle thermal reactor benchmark studies (AWBA Development Program)

International Nuclear Information System (INIS)

Ullo, J.J.; Hardy, J. Jr.; Steen, N.M.

1980-03-01

A survey is made of existing integral experiments for U233 systems and thorium-uranium based fuel systems. The aim is to understand to what extent they give a consistent test of ENDF/B-IV nuclear data. A principal result is that ENDF/B-IV leads to an underprediction of neutron leakage. Results from testing alternate thorium data sets are presented. For one evaluation due to Leonard, the results depict a possible growing discrepancy between measured integral parameters such as rho 02 and I 232 and the differential data, which underpredicts these parameters. Sensitivities to other nuclear data components, notably the fission neutron spectrum, were determined. A new harder U233 spectrum significantly reduces a bias trend in K/sub eff/ vs leakage

PWR core design, neutronics evaluation and fuel cycle analysis for thorium-uranium breeding recycle

International Nuclear Information System (INIS)

Bi, G.; Liu, C.; Si, S.

2012-01-01

This paper was focused on core design, neutronics evaluation and fuel cycle analysis for Thorium-Uranium Breeding Recycle in current PWRs, without any major change to the fuel lattice and the core internals, but substituting the UOX pellet with Thorium-based pellet. The fuel cycle analysis indicates that Thorium-Uranium Breeding Recycle is technically feasible in current PWRs. A 4-loop, 193-assembly PWR core utilizing 17 x 17 fuel assemblies (FAs) was taken as the model core. Two mixed cores were investigated respectively loaded with mixed reactor grade Plutonium-Thorium (PuThOX) FAs and mixed reactor grade 233 U-Thorium (U 3 ThOX) FAs on the basis of reference full Uranium oxide (UOX) equilibrium-cycle core. The UOX/PuThOX mixed core consists of 121 UOX FAs and 72 PuThOX FAs. The reactor grade 233 U extracted from burnt PuThOX fuel was used to fabrication of U 3 ThOX for starting Thorium-. Uranium breeding recycle. In UOX/U 3 ThOX mixed core, the well designed U 3 ThOX FAs with 1.94 w/o fissile uranium (mainly 233 U) were located on the periphery of core as a blanket region. U 3 ThOX FAs remained in-core for 6 cycles with the discharged burnup achieving 28 GWD/tHM. Compared with initially loading, the fissile material inventory in U 3 ThOX fuel has increased by 7% via 1-year cooling after discharge. 157 UOX fuel assemblies were located in the inner of UOX/U 3 ThOX mixed core refueling with 64 FAs at each cycle. The designed UOX/PuThOX and UOX/U 3 ThOX mixed core satisfied related nuclear design criteria. The full core performance analyses have shown that mixed core with PuThOX loading has similar impacts as MOX on several neutronic characteristic parameters, such as reduced differential boron worth, higher critical boron concentration, more negative moderator temperature coefficient, reduced control rod worth, reduced shutdown margin, etc.; while mixed core with U 3 ThOX loading on the periphery of core has no visible impacts on neutronic characteristics compared

Cross sections and neutron yields for U233, U235 and Pu239 at 2200 m/sec

International Nuclear Information System (INIS)

Sjoestrand, N.G.; Story, J.S.

1960-04-01

The experimental information on the 2200 m/sec values for σ abs , σ f , α, ν and η for 233 U , 235 U and 23 been collected and discussed. The values will later be used in an evaluation of a 'best' set of data. In appendix the isotopic abundances of the uranium isotopes are discussed and also the alpha activities of the uranium isotopes and Pu-239

Thermal-Neutron-Induced Fission of U235, U233 and Pu239

International Nuclear Information System (INIS)

Thomas, T.D.; Gibson, W.M.; Safford, G.J.

1965-01-01

We have used solid-state detectors to measure the kinetic energies of the coincident fission fragments in the thermal-neutron-induced fission of U 235 , U 233 and Pu 239 . Special care has been taken to eliminate spurious-events near symmetry to give an accurate measure of such quantities as the average total kinetic energy at symmetry. For each fissioning system over 10 6 events were recorded. As a result the statistics are good enough to see definite evidence for fine structure over a wide range of masses and energies. The data have been analysed to give mass yield curves, average kinetic energies as a function of mass, and other quantities of interest. For each fissioning system the average total kinetic energy goes through a maximum for a heavy fragment mass of about 132 and for the corresponding light fragment mass. There is a pronounced minimum at symmetry, although not as deep as that found in time-of-flight experiments. The difference between the maximum average kinetic energy and that at symmetry is about 32 MeV for U 235 , 18 MeV for U 233 and 20 MeV for Pu 239 . The dispersion of kinetic energies at symmetry is also smaller than that found in time-of-flight experiments. Fine structure is apparent in two different representations of the data. The energy spectrum of heavy fragments in coincidence with light fragment energies is greater than the most probable value. This structure becomes more pronounced as the light fragment energy increases. The mass yield curves for a given total kinetic energy show a structure suggesting a preference for fission fragments with masses ∼134, ∼140 and ∼145 (and their light fragment partners). Much of the structure observed can be understood by considering a semi-empirical mass surface and a simple model for the nuclear configuration at the saddle point. (author) [fr

Measurement of the fission cross section induced by fast neutrons of the {sup 232}Th/{sup 233}U nuclei within the innovating fuel cycles framework; Mesure de la section efficace de fission induite par neutrons rapides des noyaux {sup 232}Th/{sup 233}U dans le cadre des cycles de combustible innovants

Energy Technology Data Exchange (ETDEWEB)

Grosjean, C

2005-03-15

The thorium-U{sup 233} fuel cycle might provided safer and cleaner nuclear energy than the present Uranium/Pu fuelled reactors. Over the last 10 years, a vast campaign of measurements has been initiated to bring the precision of neutron data for the key nuclei (Th{sup 232}, Pa{sup 233} and U{sup 233}) at the level of those for the U-Pu cycle. This is the framework of these measurements, the energy dependent neutron induced fission cross section of Th{sup 232} and U{sup 233} has been measured from 1 to 7 MeV with a target accuracy lesser than 5 per cent. These measurements imply the accurate determination of the fission rate, the number of the target nuclei as well as the incident neutron flux impinging on the target, the latter has been obtained using the elastic scattering (n,p). The cross section of which is very well known in a large neutron energy domain ({approx} 0,5 % from 1 eV to 50 MeV) compared to the U{sup 235}(n,f) reaction. This technique has been applied for the first time to the Th{sup 232}(n,f) and U{sup 233}(n,f) cases. A Hauser-Feshbach statistical model has been developed. It consists of describing the different decay channels of the compound nucleus U{sup 234} from 0,01 to 10 MeV neutron energy. The parameters of this model were adjusted in order to reproduce the measured fission cross section of U{sup 233}. From these parameters, the cross sections from the following reactions could be extracted: inelastic scattering U{sup 233}(n,n'), radiative capture U{sup 233}(n,{gamma}) and U{sup 233}(n,2n). These cross sections are still difficult to measure by direct neutron reactions. The calculated values have allowed us to fill the lack of experimental data for the major fissile nucleus of the thorium cycle. (author)

System Requirements Document for the Molten Salt Reactor Experiment 233U conversion system

International Nuclear Information System (INIS)

Aigner, R.D.

2000-01-01

The purpose of the conversion process is to convert the 233 U fluoride compounds that are being extracted from the Molten Salt Reactor Experiment (MSRE) equipment to a stable oxide for long-term storage at Bldg. 3019

Cross sections and neutron yields for U-233, U-235 and Pu-239 at 2200 m/sec

Energy Technology Data Exchange (ETDEWEB)

Sjoestrand, N G; Story, J S

1960-04-15

The experimental information on the 2200 m/sec values for {sigma}{sub abs}, {sigma}{sub f}, {alpha}, {nu} and {eta} for {sup 233}U , {sup 235}U and {sup 23} been collected and discussed. The values will later be used in an evaluation of a 'best' set of data. In appendix the isotopic abundances of the uranium isotopes are discussed and also the alpha activities of the uranium isotopes and Pu-239.

Comparison of Hansen--Roach and ENDF/B-IV cross sections for 233U criticality calculations

International Nuclear Information System (INIS)

McNeany, S.R.; Jenkins, J.D.

1976-01-01

A comparison is made between criticality calculations performed using ENDF/B-IV cross sections and the 16-group Hansen-- Roach library at ORNL. The area investigated is homogeneous systems of highly enriched 233 U in simple geometries. Calculations are compared with experimental data for a wide range of H/ 233 U ratios. Results show that calculations of k/sub eff/ made with the Hansen--Roach cross sections agree within 1.5 percent for the experiments considered. Results using ENDF/B-IV cross sections were in good agreement for well-thermalized systems, but discrepancies up to 7 percent in k/sub eff/ were observed in fast and epithermal systems

A LMFBR for thorium utilization and for the U233/Th fuel rods specification

International Nuclear Information System (INIS)

Ishiguro, Y.; Dias, A.F.

1982-01-01

The use of U 233 /Th as fuel in the middle part of LMFBR core and the Pu/U in the external part of the core, are proposed. The basic neutronic and safety characteristics and the specifications of fuel rods to be used in the internal core, are presented. (E.G.) [pt

Use of sup(233)U for high flux reactors

International Nuclear Information System (INIS)

Sekimoto, Hiroshi; Liem, P.H.

1991-01-01

The feasibility design study on the graphite moderated gas cooled reactor as a high flux reactor has been performed. The core of the reactor is equipped with two graphite reflectors, i.e., the inner reflector and the outer reflector. The highest value of the thermal neutron flux and moderately high thermal neutron flux are expected to be achieved in the inner reflector region and in the outer reflector region respectively. This reactor has many merits comparing to the conventional high flux reactors. It has the inherent safety features associated with the modular high temperature reactors. Since the core is composed with pebble bed, the on-power refueling can be performed and the experiment time can be chosen as long as necessary. Since the thermal-to-fast flux ratio is large, the background neutron level is low and material damage induced by fast neutrons are small. The calculation was performed using a four groups diffusion approximation in a one-dimensional spherical geometry and a two-dimensional cylindrical geometry. By choosing the optimal values of the core-reflector geometrical parameters and moderator-to-fuel atomic density, high thermal neutron flux can be obtained. Because of the thermal neutron flux can be obtained. Because of the thermal design constraint, however, this design will produce a relatively large core volume (about 10 7 cc) and consequently a higher reactor power (100 MWth). Preliminary calculational results show that with an average power density of only 10 W/cc, maximum thermal neutron flux of 10 15 cm -2 s -1 can be achieved in the inner reflector. The eta value of 233 U is larger than 235 U. By introducing 233 U as the fissile material for this reactor, the thermal neutron flux level can be increased by about 15%. (author). 3 refs., 2 figs., 4 tabs

Evaluation of fission cross sections and covariances for 233U, 235U, 238U, 239Pu, 240Pu, and 241Pu

International Nuclear Information System (INIS)

Kawano, Toshihiko; Matsunobu, Hiroyuki; Murata, Toru

2000-02-01

A simultaneous evaluation code SOK (Simultaneous evaluation on KALMAN) has been developed, which is a least-squares fitting program to absolute and relative measurements. The SOK code was employed to evaluate the fission cross sections of 233 U, 235 U, 238 U, 239 Pu, 240 Pu, and 241 Pu for the evaluated nuclear data library JENDL-3.3. Procedures of the simultaneous evaluation and the experimental database of the fission cross sections are described. The fission cross sections obtained were compared with evaluated values given in JENDL-3.2 and ENDF/B-VI. (author)

The status of 232Th and 233U for CENDL-3.0

International Nuclear Information System (INIS)

Liu Ping

2003-01-01

The new version CENDL-3.0 of China: Evaluated nuclear data library has been updated, and contains about 200 nuclides. Among them, the data of following nuclides have been newly evaluated or reevaluated: fissile nuclides 15, structure materials 18, light nuclides 3, fission products 116. The 232 Th and 233 U are newly evaluated

A preliminary simulation of an ADS using MCNPX for U233 production

International Nuclear Information System (INIS)

Barros, Graiciany P.; Pereira, Claubia; Veloso, Maria A.F.; Costa, Antonella L.

2009-01-01

The code MCNPX is used to evaluate a simplified model of a hybrid system regenerator accelerator (ADS - Accelerator Driven Subcritical), for energy and 233 U production. The concept consists of coupling a high-energy particle accelerator with a sub-critical reactor core, using 232 ThO 2 + 233 UO 2 as initial composition. In this work, the spallation source definition used in MCNPX is a point source of 1000 MeV. The system consists in three coaxial cylinders. The internal cylinder is the spallation target that is a thick natural Pb. The intermediate cylinder is the core, composed by the mixture of fuel ( 232 ThO 2 + 9.5% 233 UO 2 ) and Pb coolant; and lead, as reflector, composes the external cylinder. The goal is to begin studies to evaluate the regenerator blanket composition when submitted to a neutron flux during a time step. The effective multiplication coefficient of the system and the variation of the composition of the regenerative layer are analyzed. The preliminary results show the possibility of utilization of this system. (author)

Preliminary study of the {alpha} ratio measurement, ratio of the neutron capture cross section to the fission one for {sup 233}U, on the PEREN platform. Development and study of the experimental setup; Etude preliminaire de la mesure du rapport {alpha}, rapport de la section efficace moyenne de capture sur celle de fission de l'{sup 233}U, sur la plateforme PEREN. Developpement et etude du dispositif experimental

Energy Technology Data Exchange (ETDEWEB)

Cognet, M A

2007-12-15

Producing nuclear energy in order to reduce anthropic CO{sub 2} emission and to meet high energy demand, implies three conditions to the nuclear plants of the IV. generation: safety improvements, radioactive waste minimization, and fuel breeding for a sustainable use of the resources. The Thorium fuel cycle used in Molten Salt Reactors seems promising. Many numerical studies based on probabilistic codes are carried out in order to analyse the behaviour of such reactors. Nevertheless, one of the most important parameters is badly known: the alpha ratio of {sup 233}U, ratio of the neutron capture cross section to fission one for {sup 233}U. This key-parameter is necessary to calculate the breeding ratio and thus, the deployment capacities of those reactors. This Ph-D thesis was intended to prepare a precise measurement of the alpha ratio of {sup 233}U between 1 eV and 10 keV. Preliminary measurements have been performed on the experimental platform PEREN. This experimental environment is composed of a lead slowing-down time spectrometer associated with an intense pulsed neutron generator. Capture and fission rates are measured thanks to eight scintillators with their photomultipliers, surrounding a fission chamber. A software analysis sets the coincidence rate between the scintillators. In order to understand perfectly the experimental setup, preliminary tests using a {sup 235}U fission chamber have been done. This experiment resulted in a very low signal to background ratio (1 %). The background coming from the scintillators themselves seriously handicapped the measurement. Another series of experiment has been done with scintillators 5 times thinner. Nevertheless, the signal to background ratio should still be increased to measure the capture of {sup 235}U. To make sure that the experimental setup has totally been understood, we made many comparisons between experimental results and simulations. Two simulation codes were mainly used: MCNP and GEANT4. We paid

Preliminary study of the {alpha} ratio measurement, ratio of the neutron capture cross section to the fission one for {sup 233}U, on the PEREN platform. Development and study of the experimental setup; Etude preliminaire de la mesure du rapport {alpha}, rapport de la section efficace moyenne de capture sur celle de fission de l'{sup 233}U, sur la plateforme PEREN. Developpement et etude du dispositif experimental

Energy Technology Data Exchange (ETDEWEB)

Cognet, M.A

2007-12-15

Producing nuclear energy in order to reduce anthropic CO{sub 2} emission and to meet high energy demand, implies three conditions to the nuclear plants of the IV. generation: safety improvements, radioactive waste minimization, and fuel breeding for a sustainable use of the resources. The Thorium fuel cycle used in Molten Salt Reactors seems promising. Many numerical studies based on probabilistic codes are carried out in order to analyse the behaviour of such reactors. Nevertheless, one of the most important parameters is badly known: the alpha ratio of {sup 233}U, ratio of the neutron capture cross section to fission one for {sup 233}U. This key-parameter is necessary to calculate the breeding ratio and thus, the deployment capacities of those reactors. This Ph-D thesis was intended to prepare a precise measurement of the alpha ratio of {sup 233}U between 1 eV and 10 keV. Preliminary measurements have been performed on the experimental platform PEREN. This experimental environment is composed of a lead slowing-down time spectrometer associated with an intense pulsed neutron generator. Capture and fission rates are measured thanks to eight scintillators with their photomultipliers, surrounding a fission chamber. A software analysis sets the coincidence rate between the scintillators. In order to understand perfectly the experimental setup, preliminary tests using a {sup 235}U fission chamber have been done. This experiment resulted in a very low signal to background ratio (1 %). The background coming from the scintillators themselves seriously handicapped the measurement. Another series of experiment has been done with scintillators 5 times thinner. Nevertheless, the signal to background ratio should still be increased to measure the capture of {sup 235}U. To make sure that the experimental setup has totally been understood, we made many comparisons between experimental results and simulations. Two simulation codes were mainly used: MCNP and GEANT4. We paid

Coulomb effects in isobaric cold fission from reactions 233U(nth,f), 235U(nth,f),239Pu(nth,f) and 252Cf(sf)

International Nuclear Information System (INIS)

Montoya, Modesto

2013-01-01

The Coulomb effect hypothesis, formerly used to interpret fluctuations in the curve of maximal total kinetic energy as a function of light fragment mass in reactions 233 U(n th ,f), 235 U(n th ,f) and 239 Pu(n th ,f), is confirmed in high kinetic energy as well as in low excitation energy windows, respectively. Data from reactions 233 U(n th ,f), 235 U(n th ,f), 239 Pu(n th ,f) and 252 Cf(sf) show that, between two isobaric fragmentations with similar Q-values, the more asymmetric charge split reaches the higher value of total kinetic energy. Moreover, in isobaric charge splits with different Q-values, similar preference for asymmetrical fragmentations is observed in low excitation energy windows. (author).

Preliminary study of the α ratio measurement, ratio of the neutron capture cross section to the fission one for 233U, on the PEREN platform. Development and study of the experimental setup

International Nuclear Information System (INIS)

Cognet, M.A.

2007-12-01

Producing nuclear energy in order to reduce anthropic CO 2 emission and to meet high energy demand, implies three conditions to the nuclear plants of the IV. generation: safety improvements, radioactive waste minimization, and fuel breeding for a sustainable use of the resources. The Thorium fuel cycle used in Molten Salt Reactors seems promising. Many numerical studies based on probabilistic codes are carried out in order to analyse the behaviour of such reactors. Nevertheless, one of the most important parameters is badly known: the alpha ratio of 233 U, ratio of the neutron capture cross section to fission one for 233 U. This key-parameter is necessary to calculate the breeding ratio and thus, the deployment capacities of those reactors. This Ph-D thesis was intended to prepare a precise measurement of the alpha ratio of 233 U between 1 eV and 10 keV. Preliminary measurements have been performed on the experimental platform PEREN. This experimental environment is composed of a lead slowing-down time spectrometer associated with an intense pulsed neutron generator. Capture and fission rates are measured thanks to eight scintillators with their photomultipliers, surrounding a fission chamber. A software analysis sets the coincidence rate between the scintillators. In order to understand perfectly the experimental setup, preliminary tests using a 235 U fission chamber have been done. This experiment resulted in a very low signal to background ratio (1 %). The background coming from the scintillators themselves seriously handicapped the measurement. Another series of experiment has been done with scintillators 5 times thinner. Nevertheless, the signal to background ratio should still be increased to measure the capture of 235 U. To make sure that the experimental setup has totally been understood, we made many comparisons between experimental results and simulations. Two simulation codes were mainly used: MCNP and GEANT4. We paid special attention to quantify the

Photonuclear reactions of U-233 and Pu-239 near threshold induced by thermal neutron capture gamma rays

International Nuclear Information System (INIS)

Moraes, M.A.P. de.

1990-01-01

The photonuclear cross sections of U-293 and Pu-239 have been studied by using monochromatic and discrete photons, in the energy interval from 5.49 to 9.72 MeV, produced by thermal neutron capture. The gamma fluxes incident on the samples were measured using a ( 3 x 3 )'' NaI (TI) crystal. The photofission fragments were detected in Makrofol-Kg (SSNTD). A possible structure was observed in the U-233 cross sections, near 7.23 MeV. The relative fissionability of the nuclides was determined at each excitation energy and shown to be energy independent: ( 2.12 ± 0.25) for U-233 and ( 3.32 ± 0.41 ) for Pu-239. The angular distribution of photofission fragments of Pu-239 were measured at two mean excitation energies of 5.43 and 7.35 MeV. An anisotropic distribution of ( 12.2 ± 3.6 ) % was observed at 5.43 MeV. The total neutron cross sections were measured by using a long counter detector. The photoneutron cross sections were calculated by using energy dependent neutron multiplicities values, γ(E), obtained in the literature. The competition Γn/γf was also determined at each excitation energy, and shown to be energy independent: ( 0.54 ± 0.05 ) for U-233 and ( 0.44 ± 0.05 ) for Pu-239, and were correlated to the parameters Z sup(2)/A, ( Ef'-Bn'), A. According to the FUJIMOTO-YAMAGUCHI and CONSTANT NUCLEAR TEMPERATURE models, the nuclear temperatures were calculated. The total photoabsorption cross sections were also calculated as a sum of the photofission and photoneutron cross sections at each energy excitation. From these results the competition Γf/ΓA, called fission probability Pf, were obtained: ( 0.66 ± 0.02) for U-233 and ( 0.70 ± 0.02 ) for Pu-239. (author)

The use in nuclear reactors of plutonium and U233 produced in accelerators

International Nuclear Information System (INIS)

Gambier, G.

1983-01-01

After a review of the presently known energy production systems and the estimated world's energy cumulative consumption during the next century, the author considers the production of fertile isotopes Pu239 and U233 in proton accelerators and finally their different uses in conventional PWR or FBR and the thorium cycle. (A.F.)

Development of Indian cross section data files for Th-232 and U-233 and integral validation studies

International Nuclear Information System (INIS)

Ganesan, S.

1988-01-01

This paper presents an overview of the tasks performed towards the development of Indian cross section data files for Th-232 and U-233. Discrepancies in various neutron induced reaction cross sections in various available evaluated data files have been obtained by processing the basic data into multigroup form and intercomparison of the latter. Interesting results of integral validation studies for capture, fission and (n,2n) cross sections for Th-232 by analyses of selected integral measurements are presented. In the resonance range, energy regions where significant differences in the calculated self-shielding factors for Th-232 occur have been identified by a comparison of self-shielded multigroup cross sections derived from two recent evaluated data files, viz., ENDF/B-V (Rev.2) and JENDL-2, for several dilutions and temperatures. For U-233, the three different basic data files ENDF/B-IV, JENDL-2 and ENDL-84 were intercompared. Interesting observations on the predictional capability of these files for the criticality of the spherical metal U-233 system are given. The current status of Indian data file is presented. (author) 62 ref

Strategy for the future use and disposition of uranium-233: Technical information

International Nuclear Information System (INIS)

Bereolos, P.J.; Forsberg, C.W.; Kocher, D.C.; Krichinsky, A.M.

1998-04-01

This document provides a summary of technical information on the synthetic radioisotope 233 U. It is one of a series of four reports that map out a national strategy for the future use and disposition of 233 U. The technical information on 233 U in this document falls into two main areas. First, material characteristics are presented along with the contrasts of 233 U to the more well known strategic fissile materials, 235 U and plutonium (Pu). Second, information derived from the scientific information, such as safeguards, waste classifications, material form, and packaging, is presented. Throughout, the effects of isotopically diluting 233 U with nonfissile, depleted uranium (DU) are examined

A 233U/236U/242Pu/244Pu spike for isotopic and isotope dilution analysis by mass spectrometry with internal calibration

International Nuclear Information System (INIS)

Stepanov, A.; Belyaev, B.; Buljanitsa, L.

1989-11-01

The Khlopin Radium Institute prepared on behalf of the IAEA a synthetic mixture of 233 U, 236 U, 242 Pu and 244 Pu isotopes. The isotopic composition and elemental concentration of uranium and plutonium were certified on the basis of analyses done by four laboratories of the IAEA Network, using mass spectrometry with internal standardization. The certified values for 233 U/ 236 U ratio and the 236 U chemical concentration have a coefficient of variation of 0.05%. The latter is fixed by the uncertainty in the 235 U/ 238 U ratio of NBS500 used as internal standard. The coefficients of variation of the 244 Pu/ 242 Pu ratio and the 242 Pu chemical concentration are respectively 0.10% and 0.16% and limited by the uncertainty in the 240 Pu/ 239 Pu ratio of NBS947. This four isotope mixture was used as an internal standard as well as a spike, to analyze 30 batches of LWR spent fuel solutions. The repeatability of the mass spectrometric measurements have a coefficient of variation of 0.025% for the uranium concentration, and of 0.039% for the plutonium concentration. The spiking and treatment errors had a coefficient of variation of 0.048%. (author). Refs, figs and tabs

Storage and disposition of weapons usable fissile materials (FMD) PEIS: Blending of U-233 to <12% or <5% enrichment at the Idaho National Engineering Laboratory. Data report, Draft: Version 1

International Nuclear Information System (INIS)

Shaber, E.L.

1995-08-01

Uranium-233 (U-233), a uranium isotope, is a fissionable material capable of fueling nuclear reactors or being utilized in the manufacturing of nuclear weapons. As such, it is controlled as a special nuclear material. The Idaho National Engineering Laboratory (INEL) and Oak Ridge National Laboratory (ORNL) currently store the Department of Energy's (DOE's) supply of unirradiated U-233 fuel materials. Irradiated U-233 is covered by the national spent nuclear fuel (SNF) program and is not in the scope of this report. The U-233 stored at ORNL is relatively pure uranium oxide in the form of powder or monolithic solids. This material is currently stored in stainless steel canisters of variable lengths measuring about 3 inches in diameter. The ORNL material enrichment varies with some material containing considerable amounts of U-235. The INEL material is fuel from the Light Water Breeder Reactor (LWBR) Program and consists of enriched uranium and thorium oxides in zircaloy cladding. The DOE inventory of U-233 contains trace quantities of U-232, and daughter products from the decay of U-232 and U-233, resulting in increased radioactivity over time. These increased levels of radioactivity generally result in the need for special handling considerations

Evaluation of the breed/burn fast reactor concept

International Nuclear Information System (INIS)

Atefi, B.; Driscoll, M.J.; Lanning, D.D.

1979-12-01

A core design concept and fuel management strategy, designated breed/burn, has been evaluated for heterogeneous fast breeder reactors. In this concept internal blanket assemblies after fissile material is bred in over several incore cycles, are shuffled into a moderated radial blanket and/or central island. The most promising materials combination identified used thorium in the internal blankets (due to the superior performance of epithermal Th-U233 systems) and zirconium hydride (ZrH 16 ) as the moderator

Road-map design for thorium-uranium breeding recycle in PWR - 031

International Nuclear Information System (INIS)

Shengyi, Si

2010-01-01

The paper was focused on designing a road-map to finally approach sustainable Thorium-Uranium ( 232 Th- 233 U) Breeding Recycle in current PWR, without any other change to the fuel lattice and the core internals, but substituting the UOX pellet with Thorium-based pellet. At first, the paper presented some insights to the inherence of Thorium-Uranium fuel conversion or breeding in PWR based on the neutronics theory and revealed the prerequisites for Thorium-Uranium fuel in PWR to achieve sustainable Breeding Recycle; And then, various Thorium-based fuels were designed and examined, and the calculation results further validated the above theoretical deductions; Based on the above theoretical analysis and calculation results, a road-map for sustainable Thorium-Uranium breeding recycle in PWR was outlined finally. (authors)

Thermoionic emission characteristics of uranium with application to its determination by MSID technique using 233U tracer

International Nuclear Information System (INIS)

Shihomatsu, H.M.; Iyer, S.S.

1988-01-01

Experimental details of the uranium determination in geological samples (50-1500 ppm range) by mass spectrometric isotope dilution technique (MSID) employing 233 U tracer are presented. For this purpose the thermoionic emission characteristics of uranium in various filament arrangements like simple plane, filament boat, double, are studied and the most efficient one selected for the isotope dilution analysis. The various experimental procedures involved in the MSID like sample dissolution, chemical separation and mass spectrometric analysis are developed and optimised. The experimental results on the uranium determination by MSID with 233 U tracer yielded precision and accuracy of 0,5% and 1% respectively. The importance of the sampling in the precise and accuracy determination of uranium in geological samples, where it is heterogeneously distributed, is discussed. (author) [pt

Mass dependence of azimuthal asymmetry in the fission of 232Th and 233,235,236,238U by polarized photons

International Nuclear Information System (INIS)

Denyak, V.V.; Khvastunov, V.M.; Paschuk, S.A.; Schelin, H.R.

2013-01-01

Fission of the even-even nuclei 232 Th, 236,238 U and even-odd nuclei 233,235 U by linearly polarized photons has been studied at excitation energies in the region of a giant dipole resonance. The performed investigations unambiguously showed the existence of the fragment mass dependence of the cross section azimuthal asymmetry in the photofission of 236 U and 238 U. In addition, the obtained results provided the first evidence for the possible difference between the asymmetry values in asymmetric and symmetric mass distribution regions in the case of 236 U. The measured cross section azimuthal asymmetry of the fission of 232 Th does not show any fragment mass dependence. In the even-odd nuclei 233 U and 235 U the difference between the far-asymmetric and other mass distribution regions was also observed but with the statistical uncertainty not small enough for definitive conclusion. (orig.)

Site specific health and safety plan, 233-S decontamination and decommissioning

Energy Technology Data Exchange (ETDEWEB)

J. E. Fasso

1997-12-31

The deactivated 233-S Plutonium Concentration Facility, located in the 200 Area at the Hanford Site, is the subject of this Health and Safety Plan.The 233-S Facility operated from January 1952 until July 1967 at which time the building entered the U.S. Department of Energy`s Surplus Facility Management Program as a retired facility. The facility has since undergone severe degradation due to exposure to extreme weather conditions. Additionally, the weather caused existing cracks in concrete structures of the building to lengthen, thereby increasing the potential for failed confinement of the radioactive material in the building. Differential settlement has also occurred causing portions of the facility to separate from the main building structure, increasing the potential for release of radioactive material to the environment. An expedited response is proposed to remove this threat and ensure protection of human health and the environment. On this premise it is intended that the 233-S Facility removal action be performed as a Comprehensive Environmental Response, Compensation, and Liability Act of 1980 Time-Critical Project being conducted under the Pilot Hanford Environmental Restoration (ER) Initiative

Uses for Uranium-233: What Should Be Kept for Future Needs?

International Nuclear Information System (INIS)

Forsberg, C.W.; Lewis, L.C.

1999-01-01

Since the end of the cold war, the United States has been evaluating what fissile materials to keep for potential uses and what fissile materials to declare excess. There are three major fissile materials: high-enriched uranium (HEU), plutonium, and uranium-233 ( 233 U). Both HEU and plutonium were produced in large quantities for use in nuclear weapons and for reactor fuel. Uranium-233 was investigated for use in nuclear weapons and as a reactor fuel; however, it was never deployed in nuclear weapons or used commercially as a nuclear fuel. Uranium-233 has limited current uses, but it could have several future uses. Because of (1) the cost of storing 233 U and (2) arms control considerations, the U.S. government must decide how much of the existing 233 U inventory should be kept for future use and how much should be disposed of as waste. The objective of this report is to provide technical and economic input to make a use-or-dispose decision

Monte Carlo analyses of simple U233 O2-ThO2 and U235 O2-ThO2 lattices with ENDF/B-IV data (AWBA development program)

International Nuclear Information System (INIS)

Hardy, J. Jr.; Ullo, J.J.

1980-09-01

A number of water-moderated Th-U235 and Th-U233 lattice integral experiments were analyzed in a consistent manner, with ENDF/B-IV data and detailed Monte Carlo methods. These experiments provide a consistent test of the nuclear data. The ENDF/B-IV data are found to perform reasonably well. Adequate agreement is found with integral measurements of thorium capture. Calculated K/sub eff/ values show a generally coherent pattern which is consistent with K/sub eff/ results obtained for homogeneous aqueous critical assemblies. Harder prompt fission spectra for U233 and U235 can correct the principal discrepancy observed with ENDF/B-IV, a bias trend in K/sub eff/ attributed to an underprediction of leakage

Storage and disposition of weapons usable fissile materials (FMD) PEIS: Blending of U-233 to {lt}12% or {lt}5% enrichment at the Idaho National Engineering Laboratory. Data report, Draft: Version 1

Energy Technology Data Exchange (ETDEWEB)

Shaber, E.L.

1995-08-01

Uranium-233 (U-233), a uranium isotope, is a fissionable material capable of fueling nuclear reactors or being utilized in the manufacturing of nuclear weapons. As such, it is controlled as a special nuclear material. The Idaho National Engineering Laboratory (INEL) and Oak Ridge National Laboratory (ORNL) currently store the Department of Energy`s (DOE`s) supply of unirradiated U-233 fuel materials. Irradiated U-233 is covered by the national spent nuclear fuel (SNF) program and is not in the scope of this report. The U-233 stored at ORNL is relatively pure uranium oxide in the form of powder or monolithic solids. This material is currently stored in stainless steel canisters of variable lengths measuring about 3 inches in diameter. The ORNL material enrichment varies with some material containing considerable amounts of U-235. The INEL material is fuel from the Light Water Breeder Reactor (LWBR) Program and consists of enriched uranium and thorium oxides in zircaloy cladding. The DOE inventory of U-233 contains trace quantities of U-232, and daughter products from the decay of U-232 and U-233, resulting in increased radioactivity over time. These increased levels of radioactivity generally result in the need for special handling considerations.

Fabrication of zero power reactor fuel elements containing 233U3O8 powder

International Nuclear Information System (INIS)

Nicol, R.G.; Parrott, J.R.; Krichinsky, A.M.; Box, W.D.; Martin, C.W.; Whitson, W.R.

1982-05-01

Oak Ridge National Laboratory, under contract with Argonne National Laboratory, completed the fabrication of 1743 fuel elements for use in their Zero Power Reactor. The contract also included recovery of 20 kg of 233 U from rejected elements. This report describes the steps associated with conversion of purified uranyl nitrate (as solution) to U 3 O 8 powder (suitable for fuel) and subsequent charging, sealing, decontamination, and testing of the fuel elements (packets) preparatory to shipment. The nuclear safety, radiation exposures, and quality assurance aspects of the program are discussed

Collective and single-particle excitations in the heavy deformable nuclei 234U, 233U, 231Th, 230Pa and 232Pa

International Nuclear Information System (INIS)

Kotthaus, Tanja

2010-01-01

In this thesis five heavy deformed isotopes from the mass region A≥230, namely 234 U, 233 U, 231 Th, 230 Pa and 232 Pa, were investigated by means of deuteron-induced neutron transfer reactions. The even-even isotope 234 U has been studied with the 4π-γ-spectrometer MINIBALL at the Cologne Tandem accelerator. Excited nuclei in the isotope 234 U were produced using the reaction 235 U(d,t) at a beam energy of 11 MeV. The target thickness was 3.5 mg/cm 2 . The analysis of the γγ-coincidence data yielded a reinterpretation of the level scheme in 12 cases. Considering its decay characteristics, the 4 + state at an excitation energy of 1886.7 keV is a potential candidate for a two-phonon vibrational state. The isotopes 233 U, 231 Th, 230 Pa and 232 Pa were investigated at the Munich Q3D spectrometer. For each isotope an angular distribution with angles between 5 and 45 were measured. In all four cases the energy of the polarized deuteron beam (vector polarization of 80%) was 22 MeV. As targets 234 U (160 μg/cm 2 ), 230 Th (140 μg/cm 2 ) and 231 Pa (140 μg/cm 2 ) were used. The experimental angular distributions were compared to results of DWBA calculations. For the odd isotope 233 U spin and parity for 33 states are assigned and in the other odd isotope 231 Th 22 assignments are made. The excitation spectra of the two odd-odd isotopes 230 Pa and 232 Pa were investigated for the first time. For the isotope 230 Pa 63 states below an excitation energy of 1.5 MeV are identified. Based on the new experimental data the Nilsson configuration of the ground state is either 1/2[530] p -5/2[633] n or 1/2[530] p +3/2[631] n . In addition 12 rotational bands are proposed and from this six values for the GM splitting energy are deduced as well as two new values for the Newby shift. In the other odd-odd isotope 232 Pa 40 states below an excitation energy of 850 keV are observed and suggestions for the groundstate band and its GM partner are made. From this one GM splitting

Power density effect on feasibility of water cooled thorium breeder reactor

International Nuclear Information System (INIS)

Sidik, Permana; Takaki, Naoyuki; Sekimoto, Hiroshi

2008-01-01

Breeding is made possible by the high value of neutron regeneration ratio η for 233 U in thermal energy region. The reactor is fueled by 233 U-Th oxide and it has used the light water as moderator. Some characteristics such as spectrum, η value, criticality, breeding performance and number density are evaluated. Several power densities are evaluated in order to analyze its effect to the breeding performance. The η value of fissile 233 U obtains higher value than 2 which may satisfy the breeding capability especially for thermal reactor for all investigated MFR. The increasing enrichment and decreasing conversion ratio are more significant for MFR 233 U enrichment. Number density of 233 Pa decreases significantly with decreasing power density which leads the reactor has better breeding performance because lower capture rate of 233 Pa. (author)

Determination of 233U, 235U, 238U and 239Pu fission yields induced by fission and 14.7 MeV neutrons

International Nuclear Information System (INIS)

Laurec, Jean; Adam, Albert; Bruyne, Thierry de.

1981-12-01

The 233 U, 235 U, 238 U, 239 Pu fission yields have been determined by a radiochemical method. A target and a fission chamber made of same fissible material are irradied together. The total fission number is measured from the fission chamber. The fission product activities are directly measured on the target using calibrated Ge-Li detectors. The fissible material masses are determined by alpha and mass spectrometries. The irradiations were made on the critical assemblies PROSPERO and CALIBAN and on the 14 MeV neutron generator of C.E. VALDUC. 3 to 5% fission yield errors are got for the most measured nuclides: 95 Zr, 97 Zr, 99 Mo, 103 Ru, 131 I, 132 Te, 140 Ba, 141 Ce, 143 Ce, 144 Ce, 147 Nd [fr

Water Ingress Testing of the Turbula Jar and U-233 Lead Pig Containers

Energy Technology Data Exchange (ETDEWEB)

Reeves, Kirk Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Karns, Tristan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Smith, Paul Herrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-11-02

Understanding the water ingress behavior of containers used at the TA-55 Plutonium Facility has significant implications for criticality safety. The purpose of this report is to document the water ingress behavior of the Turbula Jar with Bakelite lid and Viton gaskets (Turbula Jar) used in oxide blending operations and the U-233 lead pig container used to store and transport U-233 material. The technical basis for water resistant containers at TA-55 is described in LA-UR-15-22781, “Water Resistant Container Technical Basis Document for the TA-55 Criticality Safety Program.” Testing of the water ingress behavior of various containers is described in LA-CP-13-00695, “Water Penetration Tests on the Filters of Hagan and SAVY Containers,” LA-UR-15-23121, “Water Ingress into Crimped Convenience Containers under Flooding Conditions,” and in LA-UR- 16-2411, “Water Ingress Testing for TA-55 Containers.” Water ingress criteria are defined in TA55-AP-522 “TA-55 Criticality Safety Program”, and in PA-RD-01009 “TA55 Criticality Safety Requirements.” The water ingress criteria for submersion is no more than 50 ml of water ingress at a 6” water column height for a period of 2 hours.

The European Expression Of Interest For High Purity U-233 Materials

Energy Technology Data Exchange (ETDEWEB)

Giaquinto, Joseph M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Younkin, James R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-04-01

The purpose of this letter report is to document the response for an Expression of Interest (EOI) sent to the European Safeguards and research and development (R&D) scientific communities for the distribution of small amounts of high purity ²³³U materials for use in safeguards, nonproliferation, and basic R&D in the nuclear disciplines. The intent for the EOI was to gauge the level of international interest for these materials from government and research institutions with programmatic missions in the nuclear security or nuclear R&D arena. The information contained herein is intended to provide information to assist key decision makers in DOE as to the ultimate disposition path for the high purity materials currently being recovered at Oak Ridge National Laboratory (ORNL) and only those items for which there is no United States (U.S.) sponsor identified.

Analysis of Hydrogen Generation and Accumulation in U-233 Tube Vaults

International Nuclear Information System (INIS)

Ally, M.R.; Willis, K.J.

1999-01-01

The purpose of the 233 U Safe Storage Program is to enhance the safe storage of 233 U-bearing materials. This report describes the work done at the Oak Ridge National Laboratory's Radiochemical Development Facility (RDF) to address questions related to possible hydrogen generation and accumulation in 233 U tube vaults. The objective of this effort was to verify assumptions in the mathematical model used to estimate the hydrogen content of the gaseous atmosphere that possibly could occur inside the tube vaults in Building 3019 and to evaluate proposed measures for mitigating any hydrogen concerns. A mathematical model was developed using conservative assumptions to evaluate possible hydrogen generation and accumulation in the tube vaults. The model concluded that an equilibrium concentration would be established below the lower flammability limit (LFL) of 4.1% hydrogen. The major assumptions used in the model that were validated are as follows: (1) The shield plug does not form a seal with the tube vault wall, thus allowing the hydrogen gas to diffuse past the shield plug to the upper section of the tube vault. (2) The tube vault end-cap leaks sufficiently to allow air to be drawn into the tube vault by the off-gas system, thereby purging hydrogen from the upper section of the tube vault. (3) Any hydrogen gas generated completely mixes with the other gases present in the lower section of the tube vault and does not stratify beneath the shield plug. (4) The diffusion coefficient determined from the literature for constant diffusion of hydrogen in air is valid. The coefficient is corrected for temperatures from 0 to 25 C. Another assumption used in the model, that hydrogen generated by radiolytic decomposition of hydrogen-bearing materials (e.g., moisture and plastic) leaks from the cans under steady-state condition, as opposed to a sudden release resulting from rupture of the can(s), was beyond the scope of this investigation. Several parameters from the original

Fuel utilization improvement in PWRs using the denatured 233U-Th cycle

International Nuclear Information System (INIS)

Jones, H.M.; Schwenk, G.A.; Toops, E.C.; Yotinen, V.O.

1980-06-01

A number of changes in PWR core design and/or operating strategy were evaluated to assess the fuel utilization improvement achievable by their implementation in a PWR using thorium-based fuel and operating in a recycle mode. The reference PWR for this study was identical to the B and W Standard Plant except that the fuel pellets were of denatured ( 233 U/ 238 U-Th)O 2 . An initial scoping study identified the three most promising improvement concepts as (1) a very tight lattice, (2) thorium blankets, and (3) ThO 2 rods placed in available guide tubes. A conceptual core design incorporating these changes was then developed, and the fuel utilization of this modified design was compared with that of the reference case

Preliminary radiological safety assessment for decommissioning of thoria dissolver of the 233U pilot plant, Trombay

International Nuclear Information System (INIS)

Priya, S.; Srinivasan, P.; Gopalakrishnan, R. K.

2012-01-01

The thoria dissolver, used for separation of 233 U from reactor-irradiated thorium metal and thorium oxide rods, is no longer operational. It was decided to carry out assessment of the radiological status of the dissolver cell for planning of the future decommissioning/dismantling operations. The dissolver interiors are expected to be contaminated with the dissolution remains of irradiated thorium oxide rods in addition to some of the partially dissolved thoria pellets. Hence, 220 Rn, a daughter product of 228 Th is of major radiological concern. Airborne activity of thoron daughters 212 Pb (Th-B) and 212 Bi (Th-C) was estimated by air sampling followed by high-resolution gamma spectrometry of filter papers. By measuring the full-energy peaks counts in the energy windows of 212 Pb, 212 Bi and 208 Tl, concentrations of thoron progeny in the sampled air were estimated by applying the respective intrinsic peak efficiency factors and suitable correction factors for the equilibration effects of 212 Pb and 212 Bi in the filter paper during the delay between sampling and counting. Then the thoron working level (TWL) was evaluated using the International Commission on Radiological Protection (ICRP) methodology. Finally, the potential effective dose to the workers, due to inhalation of thoron and its progeny during dismantling operations was assessed by using dose conversion factors recommended by ICRP. Analysis of filter papers showed a maximum airborne thoron progeny concentration of 30 TWLs inside the dissolver. (authors)

Comparison of the U-233 dog data of Stevens et al. with uranium retention functions in ICRP Publication 30 and a 3-compartment mammillary model for uranium

International Nuclear Information System (INIS)

Bernard, S.R.

1983-01-01

Stevens measured the distribution, retention, and excretion of U-233 in seven beagles each given a single injection of U-233 citrate [2.8 μCi/kg U-233 (VI) (approx.3 mg/dog)]. These data, when plotted together with results obtained with the ICRP (Pub. 30) retention functions for purposes of comparison, are seen to differ only slightly from the ICRP-30 model. The number of transformations in the body, over a fifty-year period agree within a factor of 2. A three-compartment mammillary model has been parameterized from the data of Stevens by the method of Bernard. Retention in tissues of the body is represented by a linear combination of three compartments. The data plots for the dogs and ICRP-30 model will be presented and discussed together with the three compartment mammillary model for U-233 retention, distribution, and excretion. 3 figs., 2 tabs

39 CFR 233.12 - Civil penalties.

Science.gov (United States)

2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Civil penalties. 233.12 Section 233.12 Postal... Civil penalties. False representation and lottery orders— (a) Issuance. Pursuant to 39 U.S.C. 3005, the... be liable to the United States for a civil penalty in an amount not to exceed $11,000 for each day...

Study of the variation with the energy of the fission cross-sections of {sup 233}U, {sup 235}U, {sup 239}Pu for the fast neutrons; Etude de la variation avec l'energie des sections efficaces de fission de {sup 233}U, {sup 235}U, {sup 239}Pu pour les neutrons rapides

Energy Technology Data Exchange (ETDEWEB)

Szteinsznaider, D; Naggiar, V; Netter, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

This measurements have been done while taking the value of the fission cross-sections of {sup 238}U as reference. The neutrons are produced by the reaction {sup 7}Li(p,n) in the Van de Graaff generator of Saclay. The explored domain spreads from some tenths to 2000 keV. We find: for {sup 239}Pu: {sigma}{sub f} = 2,04 {+-} 0,12 barns, cross-section constant between 150 and 2000 keV, for {sup 235}U: {sigma}{sub f} = 1,15 {+-} 0,15 barns, cross-section constant between 700 and 1000 keV, for {sup 233}U: {sigma}{sub f} = 1,92 {+-} 0,25 barns, for neutrons of 850 keV. (authors) [French] Ces mesures ont ete effectuees en prenant la valeur de la section efficace de fission de {sup 238}U comme reference. Les neutrons sont produits par la reaction {sup 7}Li(p,n) au generateur Van de Graaff de Saclay. Le domaine explore s'etend de quelques dizaines de kev a 2000 kev. Nous trouvons: pour {sup 239}Pu: {sigma}{sub f} = 2,04 {+-} 0,12 barns, section efficace constante entre 150 et 2000 kev. pour {sup 235}U: {sigma}{sub f} = 1,15 {+-} 0,15 barns, section efficace constante entre 700 et 1000 kev. pour {sup 233}U: {sigma}{sub f} = 1,92 {+-} 0,25 barns, pour des neutrons de 850 kev. (auteurs)

Determination of the extraction efficiency for {sup 233}U source α-recoil ions from the MLL buffer-gas stopping cell

Energy Technology Data Exchange (ETDEWEB)

Wense, Lars v.d.; Seiferle, Benedict; Thirolf, Peter G. [Ludwig-Maximilians-Universitaet Muenchen, Garching (Germany); Laatiaoui, Mustapha [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Helmholtz Institut Mainz, Mainz (Germany)

2015-03-01

Following the α decay of {sup 233}U, {sup 229}Th recoil ions are shown to be extracted in a significant amount from the MLL buffer-gas stopping cell. The produced recoil ions and subsequent daughter nuclei are mass purified with the help of a customized quadrupole mass spectrometer. The combined extraction and mass purification efficiency for {sup 229}Th{sup 3+} is determined via MCP-based measurements and via the direct detection of the {sup 229}Th α decay. A large value of (10±2)% for the combined extraction and mass purification efficiency of {sup 229}Th{sup 3+} is obtained at a mass resolution of about 1u/e. In addition to {sup 229}Th, also other α-recoil ions of the {sup 233,} {sup 232}U decay chains are addressed. (orig.)

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)

Fission cross section ratios for 233,234,236U relative to 235U from 0.5 to 400 MeV

International Nuclear Information System (INIS)

Lisowski, P.W.; Gavron, A.; Parker, W.E.; Balestrini, S.J.; Carlson, A.D.; Wasson, O.A.; Hill, N.W.

1991-01-01

Neutron-induced fission cross section ratios from 0.5 to 400 MeV for samples of 233, 234, 236 U relative to 235 U have been measured at the WNR neutron Source at Los Alamos. The fission reaction rate was determined using a fast parallel plate ionization chamber at a 20-m flight path. Cross sections over most the energy range were also extracted using the neutron fluence determined with three different proton telescope arrangements. 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 14.1 MeV to allow us to obtain cross section section values from the ratio data and our values for 235 U(n,f). 6 refs., 1 fig

Fission cross section ratios for 233,234,236U relative to 235U from 0.5 to 400 MeV

International Nuclear Information System (INIS)

Lisowski, P.W.; Gavron, A.; Parker, W.E.; Balestrini, S.J.; Carlson, A.D.; Wasson, O.A.; Hill, N.W.

1992-01-01

Neutron-induced fission cross section ratios from 0.5 to 400 MeV for samples of 233,234,236 U relative to 235 U have been measured at the WNR neutron Source at Los Alamos. The fission reaction rate was determined using a fast parallel plate ionization chamber at a 20-m flight path. Cross sections over most of the energy range were also extracted using the neutron fluence determined with three different proton telescope arrangements. 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 14.1 MeV which will allow us to obtain cross section values from the ratio data and our values for 235 U(n, f). (orig.)

Mass dependence of azimuthal asymmetry in the fission of {sup 232}Th and {sup 233,235,236,238}U by polarized photons

Energy Technology Data Exchange (ETDEWEB)

Denyak, V.V. [National Science Center ' ' Kharkov Institute of Physics and Technology' ' , Kharkiv (Ukraine); Pele Pequeno Principe Research Institute, Curitiba (Brazil); Khvastunov, V.M. [National Science Center ' ' Kharkov Institute of Physics and Technology' ' , Kharkiv (Ukraine); Paschuk, S.A. [Federal University of Technology - Parana, Curitiba (Brazil); Schelin, H.R. [Federal University of Technology - Parana, Curitiba (Brazil); Pele Pequeno Principe Research Institute, Curitiba (Brazil)

2013-04-15

Fission of the even-even nuclei {sup 232}Th, {sup 236,238}U and even-odd nuclei {sup 233,235}U by linearly polarized photons has been studied at excitation energies in the region of a giant dipole resonance. The performed investigations unambiguously showed the existence of the fragment mass dependence of the cross section azimuthal asymmetry in the photofission of {sup 236}U and {sup 238}U. In addition, the obtained results provided the first evidence for the possible difference between the asymmetry values in asymmetric and symmetric mass distribution regions in the case of {sup 236}U. The measured cross section azimuthal asymmetry of the fission of {sup 232}Th does not show any fragment mass dependence. In the even-odd nuclei {sup 233}U and {sup 235}U the difference between the far-asymmetric and other mass distribution regions was also observed but with the statistical uncertainty not small enough for definitive conclusion. (orig.)

Evaluation of fission cross sections and covariances for {sup 233}U, {sup 235}U, {sup 238}U, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu

Energy Technology Data Exchange (ETDEWEB)

Kawano, Toshihiko [Kyushu Univ., Fukuoka (Japan); Matsunobu, Hiroyuki [Data Engineering, Inc. (Japan); Murata, Toru [AITEL Corporation, Tokyo (JP)] [and others

2000-02-01

A simultaneous evaluation code SOK (Simultaneous evaluation on KALMAN) has been developed, which is a least-squares fitting program to absolute and relative measurements. The SOK code was employed to evaluate the fission cross sections of {sup 233}U, {sup 235}U, {sup 238}U, {sup 239}Pu, {sup 240}Pu, and {sup 241}Pu for the evaluated nuclear data library JENDL-3.3. Procedures of the simultaneous evaluation and the experimental database of the fission cross sections are described. The fission cross sections obtained were compared with evaluated values given in JENDL-3.2 and ENDF/B-VI. (author)

Strategy for the future use and disposition of Uranium-233: History, inventories, storage facilities, and potential future uses

International Nuclear Information System (INIS)

Bereolos, P.J.; Lewis, L.C.

1998-06-01

This document provides background information on the man-made radioisotope 233 U. It is one of a series of four reports that map out potential national strategies for the future use and disposition of 233 U pending action under the National Environmental Policy Act (NEPA). The scope of this report is separated 233 U, where separated refers to nonwaste 233 U or 233 U that has been separated from fission products. Information on other 233 U, such as that in spent nuclear fuel (SNF), is included only to recognize that it may be separated at a later date and then fall under the scope of this report. The background information in this document includes the historical production and current inventory of 233 U, the uses of 233 U, and a discussion of the available facilities for storing 233 U. The considerations for what fraction of the current inventory should be preserved for future use depend on several issues. First, 233 U always contains a small amount of the contaminant isotope 232 U. The decay products of 232 U are highly radioactive and require special handling. The current inventory has a variety of qualities with regard to 232 U content, ranging from 1 to about 200 ppm (on a total uranium basis). It is preferable to use 233 U with the minimum amount of 232 U in all applications. The second issue pertains to other isotopes of uranium mixed in with the 233 U, specifically 235 U and 238 U. A large portion of the inventory has a high quantity of 235 U associated with it. The presence of bulk amounts of 235 U complicates storage because of the added volume needing safeguards and criticality controls. Isotopic dilution using DU may remove safeguards and criticality concerns, but it increases the overall mass and may limit applications that depend on the fissile nature of 233 U. The third issue concerns the packaging of the material. There is no standard packaging (although one is being developed); consequently, the inventory exists in a variety of packages. For some

Dicty_cDB: SHH233 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available SH (Link to library) SHH233 (Link to dictyBase) - - - Contig-U11264-1 - (Link to Or...c08.g1 Strongyloides ratti whole genome shotgun library (SRAAGSS 004) Strongyloides ratti genomic...iginal site) - - SHH233Z 563 - - - - Show SHH233 Library SH (Link to library) Clone ID SHH233 (Link to dicty...631_5( AY458631 |pid:none) Uncultured marine bacterium 159 cl... 84 3e-15 CU92816...86F1 NIH_MGC_58 Homo sapiens cDNA clone IMAGE:4069772 5', mRNA sequence. 46 0.86 1 AP008210 |AP008210.1 Oryza sativa (japonica culti

Status of thorium cycle nuclear data evaluations: Comparison of cross-section line shapes of JENDL-3 and ENDF-B-VI files for 230Th, 232Th, 231Pa, 233Pa, 232U, 233U and 234U

International Nuclear Information System (INIS)

Ganesan, S.; McLaughlin, P.K.

1992-02-01

Since 1990, one of the most interesting developments in the field of nuclear data for nuclear technology applications is that several new evaluated data files have been finalized and made available to the International Atomic Energy Agency (IAEA) for distribution to its Member States. Improved evaluated nuclear data libraries such as ENDF/B-VI from the United States and JENDL-3 from Japan were developed over a period of 10-15 years. This report is not an evaluation of the evaluations. The report as presented here gives a first look at the cross section line shapes of the isotopes that are important to the thorium fuel cycle derived from the two recently evaluated data files: JENDL-3 and ENDF/B-VI. The basic evaluated data files JENDL-3 and ENDF/B-VI were point-processed successfully using the codes LINEAR and RECENT. The point data were multigrouped in three different group structures using the GROUPIE code. Graphs of intercomparisons of cross section line shapes of JENDL-3 and ENDF/B-VI are presented in this paper for the following isotopes of major interest to studies of the thorium fuel cycle: 230 Th, 232 Th, 231 Pa, 233 Pa, 232 U, 233 U and 234 U. Comparisons between JENDL-3 and ENDF/B-VI which were performed at the point and group levels show large discrepancies in various cross sections. We conclude this report with a general remark that it is necessary to perform sensitivity studies to assess the impacts of the discrepancies between the two different sets of data on calculated reactor design and safety parameters of specific reactor systems and, based on the results of such sensitivity studies, to undertake new tasks of evaluations. (author). 2 refs, 245 figs, 8 tabs

On the Relative Signs of "ROT-Effects" in Ternary and Binary Fission of 233U and 235U Nuclei Induced by Polarized Cold Neutrons

Science.gov (United States)

Danilyan, G. V.

2018-02-01

Signs of the ROT-effects in ternary fission of 233U and 235U experimentally defined by PNPI group are the same, whereas in binary fission defined by ITEP group are opposite. This contradiction cannot be explained by the errors in the experiments of both groups, since such instrumental effects would be too large not to be noticed. Therefore, it is necessary to find the answer to this problem in the differences of the ternary and binary fission mechanisms.

Using {sup 233}U-doped crystals to access the few-eV isomeric transition in {sup 229}Th

Energy Technology Data Exchange (ETDEWEB)

Stellmer, Simon; Schreitl, Matthias; Kazakov, Georgy A.; Sterba, Johannes H.; Schumm, Thorsten [Vienna Center for Quantum Science and Technology (VCQ) and Atominstitut, TU Wien, Vienna (Austria)

2016-07-01

The isotope {sup 229}Th possesses an exceptionally low-lying isomeric state at an energy of only a few eV. While direct laser excitation of the isomer is a tantalizing future prospect, the stage is not yet set for nuclear laser spectroscopy: too little is known about the energy, lifetime, and internal conversion pathways of the isomer. Alternative routes to populate the isomer are needed for further investigations. We use the alpha decay {sup 233}U →{sup 229g,m}Th to populate the isomer with a probability of 2%. The {sup 233}U is embedded into VUV-transparent crystals, as the isomer transition is expected around 160 nm. The wavelength of the gamma ray, emitted upon de-excitation of the isomer into the ground state, is measured with a spectrometer. Calculations show that the isomer emission is not obscured by radioluminescence of the crystal. We report on the current status of the experiment.

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

Development of automation and remotisation systems for fabrication of (Th-233U)O2 MOX fuel for AHWR

International Nuclear Information System (INIS)

Saraswat, Anupam; Danny, K.M.; Chakraborty, S.; Somayajulu, P.S.; Kumar, Arun; Mittal, R.; Prasad, R.S.; Mahule, K.N.; Panda, S.; Jayarajan, K.

2011-01-01

To meet the ever increasing power requirement of India, country is planning to utilize its large thorium reserves for the third stage of nuclear power program based on Thorium-Uranium 233 fuel in A.H.W.R. Although there are many advantages of (Th- 233 U)O 2 fuel cycle, presence of radiological hazards due to the presence of 1000-2000 ppm level of 232 U in the 233 U fuel and inertness of ThO 2 makes handling and fabrication of fuel difficult. The associated high alpha and gamma activity demands high level of automation and remote handling in alpha tight hot cells. To demonstrate automation and remotisation in (Th- 233 U)O 2 fuel fabrication, a mock up facility is being set up at BARC. This facility shall develop automation systems required for remote fuel fabrication in a simulated hot cell environment. There are many innovative schemes and systems being developed like integrated powder pellet system, remote viewing system for hot cell application etc. Low visibility inside the hot cell has always been a problem for the operator. To overcome this problem a remote viewing system has been developed by which entire hot cell area can be scanned with the use of a joystick and the display can be seen on a LCD monitor. The viewing system is made up of radiation resistant optics which can work even in high gamma fields. It consists of objective end assembly which is used to scan the hot cell area with the help of prism doublets and drive mechanism for capturing full 360 deg solid angle view. There is a Galilean telescope and focusing system used for focusing images of distant objects. Drive mechanism can be controlled by the joystick available to the operator. System has a high resolution CCD display and camera which gives a clear display of objects lying inside the hot cell area. Integrated powder pellet system is being developed for fabrication of MOX pellets from feed powder. This will be automated system which will take input in the form of MOX powder and convert it

Measurement of the $^{233}$U neutron capture cross section at the n_TOF facility at CERN

CERN Document Server

Carrapiço, Carlos; Berthoumieux, Eric; Gonçalves, Isabel; Gunsing, Frank

2012-12-12

The Thorium-Uranium (Th-U) fuel cycle has been envisaged as an alternative to the Uranium-Plutonium (U-Pu) fuel cycle for electricity generation using nuclear power reactors. Indeed, thorium can be used as a nuclear fuel, and several studies and R&D programs seem to provide evidence on the sustainability of the Th-U fuel cycle, due to (i) the natural abundance of Thorium, (ii) the improved proliferation resistance offered by the Th-U fuel cycle relative to the U-Pu fuel cycle, (iii) the better neutronics performance of the Th-U fuel cycle throughout the whole neutron energy range compared to the U-Pu fuel cycle, (iv) the lower radiotoxicity of the generated spent fuel in reactors with Th-U fuel cycle and, consequently (v) better economics and public acceptance of the reactors operated using the Th-U fuel cycle compared to those using the U-Pu fuel cycle (prior to the Generation IV nuclear reactors). In a nuclear reactor operated using the Th-U fuel cycle, $^{233}$U is a key nuclide governing the neutr...

Advantages and implications of U233 fueled thermionic space power energy conversion

International Nuclear Information System (INIS)

Terrell, C.W.

1992-01-01

In this paper two recent analyses are reported which demonstrate advantages of a U233 fueled thermionic fuel element (TFE) compared to 93 w/o U235, and that application (mission) has broad latitude in how space power reactor systems could or should be optimized. A reference thermionic reactor system was selected to provide the basis for the fuel comparisons. Both oxide and metal fuel forms were compared. Of special interest was to estimate the efficiencies of the four fuel forms to produce electrical power. A figure of merit (FOM) was defined which is directly proportional to the electrical average electrical power produced is proportional to the electrical power produced per unit uranium mass. In a TFE the average electrical power produced is proportional to the emitter surface area (Esa), hence the ratio Esa/Mu was selected as the FOM. Results indicate that the choice of fuel type and form leads to wide variations in critical and system masses FOM values, and system total power

Study of the variation with the energy of the fission cross-sections of 233U, 235U, 239Pu for the fast neutrons

International Nuclear Information System (INIS)

Szteinsznaider, D.; Naggiar, V.; Netter, F.

1955-01-01

This measurements have been done while taking the value of the fission cross-sections of 238 U as reference. The neutrons are produced by the reaction 7 Li(p,n) in the Van de Graaff generator of Saclay. The explored domain spreads from some tenths to 2000 keV. We find: for 239 Pu: σ f = 2,04 ± 0,12 barns, cross-section constant between 150 and 2000 keV, for 235 U: σ f = 1,15 ± 0,15 barns, cross-section constant between 700 and 1000 keV, for 233 U: σ f = 1,92 ± 0,25 barns, for neutrons of 850 keV. (authors) [fr

Accelerator molten-salt breeding and thorium fuel cycle

International Nuclear Information System (INIS)

Furukawa, Kazuo; Nakahara, Yasuaki; Kato, Yoshio; Ohno, Hideo; Mitachi, Kohshi.

1990-01-01

The recent efforts at the development of fission energy utilization have not been successful in establishing fully rational technology. A new philosophy should be established on the basis of the following three principles: (1) thorium utilization, (2) molten-salt fuel concept, and (3) separation of fissile-breeding and power-generating functions. Such philosophy is called 'Thorium Molten-Salt Nuclear Energy Synergetics [THORIMS-NES]'. The present report first addresses the establishment of 233 U breeding fuel cycle, focusing on major features of the Breeding and Chemical Processing Centers and a small molten-salt power station (called FUJI-II). The development of fissile producing breeders is discussed in relation to accelerator molten-salt breeder (AMSB), impact fusion molten-salt breeder, and inertial-confined fusion hybrid molten-salt breeder. Features of the accelerator molten-salt breeder are described, focusing on technical problems with accelerator breeders (or spallators), design principle of the accelerator molten-salt breeder, selection of molten salt compositions, and nuclear- and reactor-chemical aspects of AMSB. Discussion is also made of further research and development efforts required in the future for AMSB. (N.K.)

Evaluation of temperature coefficients of reactivity for 233U--thorium fueled HTGR lattices. Final report

International Nuclear Information System (INIS)

Newman, D.F.; Leonard, B.R. Jr.; Trapp, T.J.; Gore, B.F.; Kottwitz, D.A.; Thompson, J.K.; Purcell, W.L.; Stewart, K.B.

1977-05-01

A comparison of calculated and measured neutron multiplication factors as a function of temperature was made for three graphite-moderated lattices in the High Temperature Lattice Test Reactor (HTLTR) using 233 UO 2 --ThO 2 fuels in varying amounts and configurations. Correlation of neutronic analysis methods and cross section data with the experimental measurements forms the basis for assessing the accuracy of the methods and data and developing confidence in the ability to predict the temperature coefficient of reactivity for various High Temperature Gas-Cooled Reactor (HTGR) conditions in which 233 U and thorium are present in the fuel. The calculated values of k/sub infinity/(T) were correlated with measured values using two least-squares-fitted correlation coefficients: (1) a normalization factor, and (2) a temperature coefficient bias factor. These correlations indicate the existence of a negative (nonconservative) bias in temperature coefficients of reactivity calculated using ENDF/B-IV cross section data

Fission cross section ratios for sup 233,234,236 U relative to sup 235 U from 0. 5 to 400 MeV

Energy Technology Data Exchange (ETDEWEB)

Lisowski, P.W.; Gavron, A.; Parker, W.E.; Balestrini, S.J. (Los Alamos National Lab., NM (USA)); Carlson, A.D.; Wasson, O.A. (National Inst. of Standards and Technology, Gaithersburg, MD (USA)); Hill, N.W. (Oak Ridge National Lab., TN (USA))

1991-01-01

Neutron-induced fission cross section ratios from 0.5 to 400 MeV for samples of {sup 233, 234, 236}U relative to {sup 235}U have been measured at the WNR neutron Source at Los Alamos. The fission reaction rate was determined using a fast parallel plate ionization chamber at a 20-m flight path. Cross sections over most the energy range were also extracted using the neutron fluence determined with three different proton telescope arrangements. Those 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 value for {sup 235}U(n,f) at 14.1 MeV to allow us to obtain cross section section values from the ratio data and our values for {sup 235}U(n,f). 6 refs., 1 fig.

Measurements of neutron induced capture and fission reactions on $^{233}$ U (EAR1)

CERN Multimedia

The $^{233}$U plays the essential role of ssile nucleus in the Th-U fuel cycle, which has been proposed as a safer and cleaner alternative to the U-Pu fuel cycle. Considered the scarce data available to assess the capture cross section, a measurement was proposed and successfully performed at the n_TOF facility at CERN using the 4$\\pi$ Total Absorp- tion Calorimeter (TAC). The measurement was extremely dicult due to the need to accurately distinguish between capture and fission $\\gamma$-rays without any additional discrim-ination tool and the measured capture cross section showed a signicant disagreement in magnitude when compared with the ENDF/B-VII.1 library despite the agreement in shape. We propose a new measurement that is aimed at providing a higher level of dis-crimination between competing nuclear reactions, to extend the neutron energy range and to obtain more precise and accurate data, thus fullling the demands of the "NEA High Priority Nuclear Data Request List". The setup is envisaged as a combin...

Material control and accountability aspects of safeguards for the USA 233U/Th fuel recycle plant

International Nuclear Information System (INIS)

Carpenter, J.A. Jr.; McNeany, S.R.; Angelini, P.; Holder, N.D.; Abraham, L.

1978-01-01

The materials control and accountability aspects of the reprocessing and refabrication of a conceptual large-scale HTGR fuel recycle plant have been discussed. Two fuel cycles were considered. The traditional highly enriched uranium cycle uses an initial or makeup fuel element with a fissile enrichment of 93% 235 U. The more recent medium enriched uranium cycle uses initial or makeup fuel elements with a fissile enrichment less than 20% 235 U. In both cases, 233 U bred from the fertile thorium is recycled. Materials control and accountability in the plant will be by means of a real-time accountability method. Accountability data will be derived from monitoring of total material mass through the processes and a system of numerous assays, both destructive and nondestructive

Calculated critical parameters in simple geometries for oxide and nitrate water mixtures of U-233, U-235 and Pu-239 with thorium. Final report

International Nuclear Information System (INIS)

Converse, W.E.; Bierman, S.R.

1979-11-01

Calculations have been performed on water mixtures of oxides and nitrates of 233 U, 235 U, and 239 Pu with chemically similar thorium compounds to determine critical dimensions for simple geometries (sphere, cylinder, and slab). Uranium enrichments calculated were 100%, 20%, 10%, and 5%; plutonium calculations assumed 100% 239 Pu. Thorium to uranium or plutonium weight ratios (Th: U or Pu) calculated were 0, 1, 4, and 8. Both bare and full water reflection conditions were calculated. The results of the calculations are plotted showing a critical dimension versus the uranium or plutonium concentration. Plots of K-infinity and material buckling for each material type are also shown

Uranium-233 waste definition: Disposal options, safeguards, criticality control, and arms control

International Nuclear Information System (INIS)

Forsberg, C.W.; Storch, S.N.; Lewis, L.C.

1998-01-01

The US investigated the use of 233 U for weapons, reactors, and other purposes from the 1950s into the 1970s. Based on the results of these investigations, it was decided not to use 233 U on a large scale. Most of the 233 U-containing materials were placed in long-term storage. At the end of the cold war, the US initiated, as part of its arms control policies, a disposition program for excess fissile materials. Other programs were accelerated for disposal of radioactive wastes placed in storage during the cold war. Last, potential safety issues were identified related to the storage of some 233 U-containing materials. Because of these changes, significant activities associated with 233 U-containing materials are expected. This report is one of a series of reports to provide the technical bases for future decisions on how to manage this material. A basis for defining when 233 U-containing materials can be managed as waste and when they must be managed as concentrated fissile materials has been developed. The requirements for storage, transport, and disposal of radioactive wastes are significantly different than those for fissile materials. Because of these differences, it is important to classify material in its appropriate category. The establishment of a definition of what is waste and what is fissile material will provide the guidance for appropriate management of these materials. Wastes are defined in this report as materials containing sufficiently small masses or low concentrations of fissile materials such that they can be managed as typical radioactive waste. Concentrated fissile materials are defined herein as materials containing sufficient fissile content such as to warrant special handling to address nuclear criticality, safeguards, and arms control concerns

Study of the mass, isotopic and kinetic energy distributions of the 233U(nth, f) and 241Pu(nth, f) fission products measured at the Lohengrin mass spectrometer (ILL)

International Nuclear Information System (INIS)

Martin, F.

2013-01-01

Fission product yields are significant nuclear data for neutronic simulations. The purpose of this work is to improve fission yield knowledge for two fissile nuclei: 241 Pu and 233 U. Those are respectively involved in the uranium and thorium nuclear fuel cycle. The measurements are performed at the Lohengrin mass spectrometer of the Institut Laue-Langevin (ILL) located in Grenoble. The spectrometer is combined with an ionization chamber to measure mass yields of 241 Pu and 233 U and with a gamma spectrometry set-up to determine isotopic yields of 233 U. A new analysis method of experimental data has been developed in order to control systematics and to reduce experimental biases. For the first time, the experimental variance-covariance matrix of our measured fission yields could be deduced. (author) [fr

Evaluation of neutron nuclear data for 233U in thermal and resonance regions

International Nuclear Information System (INIS)

Kikuchi, Yasuyuki

1981-02-01

The thermal and resonance cross sections of 233 U were evaluated for JENDL-2. The cross sections below 1 eV are given as point-wise data and were evaluated by the use of the measured fission and capture cross sections. The resolved resonance parameters are derived up to 100 eV. The parameters were obtained by using NDES so as to reproduce the measured total and fission cross sections. The cross sections from 100 eV to 30 keV are represented by the unresolved resonance parameters. The fission and capture resonance integrals calculated from these parameters are 771 and 138 barns, respectively, which agree with the measured data within the quoted errors. (author)

Simultaneous measurement of neutrons and fission fragments of thermal neutron fission of U-233

International Nuclear Information System (INIS)

Itsuro Kimura; Katsuhisa Nishio; Yoshihiro Nakagome

2000-01-01

The multiplicity and the energy of prompt neutrons from the fragments for 233 U(n th , f) were measured as functions of fragment mass and total kinetic energy. Average neutron energy against the fragment mass showed a nearly symmetric distribution about the half mass division with two valleys at 98 and 145 u. The slope of the neutron multiplicity with total kinetic energy depended on the fragment mass and showed the minimum at about 130 u. The obtained neutron data were applied to determine the total excitation energy of the system, and the resulting value in the typical asymmetric fission lied between 22 and 25 MeV. The excitation energy agreed with that determined by subtracting the total kinetic energy from the Q-value within 1 MeV, thus satisfied the energy conservation. In the symmetric fission, where the mass yield was drastically suppresses, the total excitation energy is significantly large and reaches to about 40 MeV, suggesting that fragment pairs are preferentially formed in a compact configuration at the scission point [ru

Fission cross-section measurements on 233U and minor actinides at the CERN n-TOF facility

International Nuclear Information System (INIS)

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

2010-01-01

Neutron-induced fission cross-sections of minor actinides have been measured at the white neutron source n-TOF at CERN, Geneva. The studied isotopes include 233 U, interesting for Th/U based nuclear fuel cycles, 241, 243 Am and 245 Cm, relevant for transmutation and waste reduction studies in new generation fast reactors (Gen-IV) or Accelerator Driven Systems. The measurements take advantage of the unique features of the n-TOF facility, namely the wide energy range, the high instantaneous neutron flux and the low background. Results for the involved isotopes are reported from ∼30 meV to around 1 MeV neutron energy. The measurements have been performed with a dedicated Fission Ionization Chamber (FIC), relative to the standard cross-section of the 235 U fission reaction, measured simultaneously with the same detector. Results are here reported. (authors)

19 CFR 10.233 - Articles eligible for preferential tariff treatment.

Science.gov (United States)

2010-04-01

... control of the customs authority of the intermediate country; (ii) Did not enter into the commerce of the... 19 Customs Duties 1 2010-04-01 2010-04-01 false Articles eligible for preferential tariff treatment. 10.233 Section 10.233 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND...

Study of electrodeposition technique to prepare alpha-counting plates of uranium 233

International Nuclear Information System (INIS)

Mertzig, W.

1979-01-01

The electrodeposition technique to prepare alpha-counting plates of 233 U for its determination is presented. To determine the optimum conditions for plating 233 U the effects of such parameters as current density, pH of eletrotype, salt concentration, time of electrolysis and distance electrodes were studied. A carrier method was developed to attain a quantitative electrodeposition of 233 U from aqueous solutions into alpha counting paltes. A single and incremental addition of natural uranium and thorium as carrier were studied. All samples were prepared using a electrodeposition cell manufactured at the IPEN, especially for use in electroplating tracer actinides. This cell is made of a metal-lucite to contain the electrolyte, which bottom is a polished brass disk coated with a Ni film serving as the cathode. A Pt wire anode is fixed on the top of the cell. The electroplated samples were alpha-counted using a surface barrier detector. A recovery of more than 99% was obtained in specific conditions. The plating procedure produced deposits which were firmly distributed over the plate area. The method was applied to determine tracer amounts of 233 U from oxalate and nitrate solutions coming from chemical processing irradiated thorium. (Author) [pt

Absolute M1 and E2 Transition Probabilities in 233U

International Nuclear Information System (INIS)

Malmskog, S.G.; Hoejeberg, M.

1967-08-01

Using the delayed coincidence technique, the following half lives have been determined for different excited states in 233 U: T 1/2 (311.9 keV level) = (1.20 ± 0.15) x 10 -10 sec, T 1/2 (340.5 keV level) = (5.2 ± 1.0) x 10 -11 sec, T 1/2 (398.6 keV level) = (5.5 ± 2.0) x 10 -11 sec and T 1/2 (415.8 keV level) -11 sec. From these half life determinations, together with earlier known electron intensities and conversion coefficients, 22 reduced B(Ml) and B(E2) transition probabilities (including 9 limits) have been deduced. The rotational transitions give information on the parameters δ and (g K - g R ) . The experimental M1 and E2 transition rates between members of different bands have been analysed in terms of the predictions of the Nilsson model, taking also pairing correlations and Coriolis coupling effects into account

Delayed Fission Gamma-ray Characteristics of Th-232 U-233 U-235 U-238 and Pu-239

Energy Technology Data Exchange (ETDEWEB)

Lane, Taylor [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Parma, Edward J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

2015-08-01

Delayed fission gamma-rays play an important role in determining the time dependent ioniz- ing dose for experiments in the central irradiation cavity of the Annular Core Research Reactor (ACRR). Delayed gamma-rays are produced from both fission product decay and from acti- vation of materials in the core, such as cladding and support structures. Knowing both the delayed gamma-ray emission rate and the time-dependent gamma-ray energy spectrum is nec- essary in order to properly determine the dose contributions from delayed fission gamma-rays. This information is especially important when attempting to deconvolute the time-dependent neutron, prompt gamma-ray, and delayed gamma-ray contribution to the response of a diamond photo-conducting diode (PCD) or fission chamber in time frames of milliseconds to seconds following a reactor pulse. This work focused on investigating delayed gamma-ray character- istics produced from fission products from thermal, fast, and high energy fission of Th-232, U-233, U-235, U-238, and Pu-239. This work uses a modified version of CINDER2008, a transmutation code developed at Los Alamos National Laboratory, to model time and energy dependent photon characteristics due to fission. This modified code adds the capability to track photon-induced transmutations, photo-fission, and the subsequent radiation caused by fission products due to photo-fission. The data is compared against previous work done with SNL- modified CINDER2008 [ 1 ] and experimental data [ 2 , 3 ] and other published literature, includ- ing ENDF/B-VII.1 [ 4 ]. The ability to produce a high-fidelity (7,428 group) energy-dependent photon fluence at various times post-fission can improve the delayed photon characterization for radiation effects tests at research reactors, as well as other applications.

Aerosols generated by 239PU and 233U droplets burning in air

International Nuclear Information System (INIS)

Nelson, L.S.; Raabe, O.G.

1978-01-01

The inhalation hazards of radioactive aerosols produced by the explosive disruption and subsequent combustion of metallic plutonium in air are not adequately understood. Results of a study to determine whether uranium can be substituted for plutonium in such a situation in which experiments were performed under identical conditions with laser-ignited, single, freely falling droplets of 239 Pu and 233 U are reported. The total amounts of aerosol produced were studied quantitatively as a function of time during the combustion. Also, particle size distributions of selected aerosols were studied with aerodynamic particle separation techniques. Results showed that the ultimate quantity of aerosols, their final particle size distributions, and depositions as a function of time are not identical mainly because of the different vapor pressures of the metals, and the unlike degrees of violence of the explosions of the droplets

Fusion-supported decentralized nuclear energy system

International Nuclear Information System (INIS)

Jassby, D.L.

1979-04-01

A decentralized nuclear energy system is proposed comprising mass-produced pressurized water reactors in the size range 10 to 300 MW (thermal), to be used for the production of process heat, space heat, and electricity in applications where petroleum and natural gas are presently used. Special attention is given to maximizing the refueling interval with no interim batch shuffling in order to minimize fuel transport, reactor downtime, and opportunity for fissile diversion. These objectives demand a substantial fissile enrichment (7 to 15%). The preferred fissile fuel is U-233, which offers an order of magnitude savings in ore requirements (compared with U-235 fuel), and whose higher conversion ratio in thermal reactors serves to extend the period of useful reactivity and relieve demand on the fissile breeding plants (compared with Pu-239 fuel). Application of the neutral-beam-driven tokamak fusion-neutron source to a U-233 breeding pilot plant is examined. This scheme can be extended in part to a decentralized fusion energy system, wherein remotely located large fusion reactors supply excess tritium to a distributed system of relatively small nonbreeding D-T reactors

The effect of breed on fatty acid composition of subcutaneous ...

African Journals Online (AJOL)

A study was conducted to evaluate the fatty acid (FA) profile of subcutaneous adipose tissue and tailfat of two fat-tailed sheep breeds under identical feeding conditions. Twelve male lambs from two breeds, Sanjabi (n = 6), weighing 23.3 ± 0.48 kg, and Mehraban (n = 6), weighing 26.1 ± 2.14 kg, were used in this ...

Recovery of thorium along with uranium 233 from Thorex waste solution employing Chitosan

International Nuclear Information System (INIS)

Priya, S.; Reghuram, D.; Kumaraguru, K.; Vijayan, K.; Jambunathan, U.

2003-01-01

The low level waste solution, generated from Thorex process during the processing of U 233 , contains thorium along with traces of Th 228 and U 233 . Chitosan, a natural bio-polymer derived from Chitin, was earlier used to recover the uranium and americium. The studies were extended to find out its thorium sorption characteristics. Chitosan exhibited very good absorption of thorium (350 mg/g). Chitosan was equilibrated directly with the low level waste solution at different pH after adjusting its pH, for 60 minutes with a Chitosan to aqueous ratio of 1:100 and the raffinates were filtered and analysed. The results showed more than 99% of thorium and U 233 could be recovered by Chitosan between pH 4 and 5. Loaded thorium and uranium could be eluted from the Chitosan by 1M HNO 3 quantitatively. (author)

Design Feasible Area on Water Cooled Thorium Breeder Reactor in Equilibrium States

International Nuclear Information System (INIS)

Sidik Permana; Naoyuki Takaki; Hiroshi Sekimoto

2006-01-01

Thorium as supplied fuel has good candidate for fuel material if it is converted into fissile material 233 U which shows superior characteristics in the thermal region. The Shippingport reactor used 233 U-Th fuel system, and the molten salt breeder reactor (MSBR) project showed that breeding is possible in a thermal spectrum. In the present study, feasibility of water cooled thorium breeder reactor is investigated. The key properties such as flux, η value, criticality and breeding performances are evaluated for different moderator to fuel ratios (MFR) and burn-ups. The results show the feasibility of breeding for different MFR and burn-ups. The required 233 U enrichment is about 2% - 9% as charge fuel. The lower MFR and the higher enrichment of 233 U are preferable to improve the average burn-up; however the design feasible window is shrunk. This core shows the design feasible window especially in relation to MFR with negative void reactivity coefficient. (authors)

Multiplicity and energy of neutrons from {sup 233}U(n{sub th},f) fission fragments

Energy Technology Data Exchange (ETDEWEB)

Nishio, Katsuhisa; Kimura, Itsuro; Nakagome, Yoshihiro [Kyoto Univ. (Japan)

1998-03-01

The correlation between fission fragments and prompt neutrons from the reaction {sup 233}U(n{sub th},f) was measured with improved accuracy. The results determined the neutron multiplicity and emission energy as a function of fragment mass and total kinetic energy. The average energy as a function of fragment mass followed a nearly symmetric distribution centered about the equal mass-split and formed a remarkable contrast with the saw-tooth distribution of the average neutron multiplicity. The neutron multiplicity from the specified fragment decreases linearly with total kinetic energy, and the slope of multiplicity with kinetic energy had the minimum value at about 130 u. The level density parameter versus mass determined from the neutron data showed a saw-tooth structure with the pronounced minimum at about 128 and generally followed the formula by Gilbert and Cameron, suggesting that the neutron emission process was very much affected by the shell-effect of the fission fragment. (author)

Influence of Contact Time on the Extraction of 233Uranyl Spike and Contaminant Uranium From Hanford Sediment

International Nuclear Information System (INIS)

Smith, Steven C.; Szecsody, James E.

2011-01-01

In this study 233Uranyl nitrate was added to uranium (U) contaminated Hanford 300 Area sediment and incubated under moist conditions for 1 year. It hypothesized that geochemical transformations and/or physical processes will result in decreased extractability of 233U as the incubation period increases, and eventually the extraction behavior of the 233U spike will be congruent to contaminant U that has been associated with sediment for decades. Following 1 week, 1 month, and 1 year incubation periods, sediment extractions were performed using either batch or dynamic (sediment column flow) chemical extraction techniques. Overall, extraction of U from sediment using batch extraction was less complicated to conduct compared to dynamic extraction, but dynamic extraction could distinguish the range of U forms associated with sediment which are eluted at different times.

Dissolution rates of unirradiated UO2, UO2 doped with 233U, and spent fuel under normal atmospheric conditions and under reducing conditions using an isotope dilution method

International Nuclear Information System (INIS)

Ollila, Kaija; Albinsson, Yngve; Oversby, Virginia; Cowper, Mark

2003-10-01

The experimental results given in this report allow us to draw the following conclusions. 1) Tests using unirradiated fuel pellet materials from two different manufacturers gave very different dissolution rates under air atmosphere testing. Tests for fragments of pellets from different pellets made by the same manufacturer gave good agreement. This indicates that details of the manufacturing process have a large effect on the behavior of unirradiated UO 2 in dissolution experiments. Care must be taken in interpreting differences in results obtained in different laboratories because the results may be affected by manufacturing effects. 2) Long-term tests under air atmosphere have begun to show the effects of precipitation. Further testing will be needed before the samples reach steady state. 3) Testing of unirradiated UO 2 in systems containing an iron strip to produce reducing conditions gave [U] less than detection limits ( 235 U added as spike was recovered, indicating that 90% of the spike had precipitated onto the solid sample or the iron strip. 9) Tests of UO 2 pellet materials containing 233 U to provide an alpha decay activity similar to that expected for spent fuel 3000 and 10,000 years after disposal showed that the pellet materials behaved as expected under air atmosphere conditions, showing that the manufacturing method was successful. 10) Early testing of the 233 U-doped materials under reducing conditions showed relatively rapid (30 minute) dissolution of small amounts of U at the start of the puff test procedure. Results of analyses of an acidified fraction of the same solutions after 1 or 2 weeks holding indicate that the solutions were inhomogeneous, indicating the presence of colloidal material or small grains of solid. 11) Samples from the 233 U-doped tests initially indicated dissolution of solid during the first week of testing, with some indication of more rapid dissolution of the material with the higher doping. 12) The second cycle of testing

Fabrication routes for Thorium and Uranium233 based AHWR fuel

International Nuclear Information System (INIS)

Danny, K.M.; Saraswat, Anupam; Chakraborty, S.; Somayajulu, P.S.; Kumar, Arun

2011-01-01

India's economic growth is on a fast growth track. The growth in population and economy is creating huge demand for energy which has to be met with environmentally benign technologies. Nuclear Energy is best suited to meet this demand without causing undue environmental impact. Considering the large thorium reserves in India, the future nuclear power program will be based on Thorium- Uranium 233 fuel cycle. The major characteristic of thorium as the fuel of future comes from its superior fuel utilization. 233 U produced in a reactor is always contaminated with 232 U. This 232 U undergoes a decay to produce 228 Th and it is followed by decay chain including 212 Bi and 208 Tl. Both 212 Bi and 208 Tl are hard gamma emitters ranging from 0.6 MeV-1.6 MeV and 2.6 MeV respectively, which necessitates its handling in hot cell. The average concentration of 232 U is expected to exceed 1000 ppm after a burn-up of 24,000 MWD/t. Work related to developing the fuel fabrication technology including automation and remotization needed for 233 U based fuels is in progress. Various process for fuel fabrication have been developed i.e. Coated Agglomerate Pelletisation (CAP), impregnation technique (Pellet/Gel), Sol Gel Micro-sphere Pelletisation (SGMP) apart from Powder to Pellet (POP) route. This paper describes each process with respect to its advantages, disadvantages and its amenability to automation and remotisation. (author)

Narrowband tunable laser for uranium-233 cleanup process

International Nuclear Information System (INIS)

Singh, Sunita; Sridhar, G.; Rawat, V.S.; Kawde, Nitin; Sinha, A.K.; Bhatt, S.; Gantayet, L.M.

2009-01-01

Design, development and technology demonstration of proto type Single Longitudinal Mode pulsed tunable laser is reported in this work. The tunable laser has a narrow bandwidth less than 400 MHz required for isotopic clean up of 233 U. (author)

Chemical and spectrochemical production analysis of ThO2 and 233UO2-ThO2 pellets for the light water breeder reactor core for Shippingport (LWBR development program)

International Nuclear Information System (INIS)

Bukowski, J.F.; Hollis, E.D.

1975-06-01

The Bettis Atomic Power Laboratory has utilized wet chemical, emission spectrochemical, and mass spectrometric analytical techniques for the production analysis of the ThO 2 and 233 UO 2 -ThO 2 (1 to 6 wt percent 233 UO 2 ) pellets for the Light Water Breeder Reactor (LWBR) core for Shippingport. Proof of the fuel breeding concept necessitates measurement of precise and accurate chemical characterization of all fuel pellets before core life. Chemistry's efforts toward this goal are presented in three main sections: (1) general discussions relating the chemical requirements for ThO 2 and 233 UO 2 -ThO 2 core materials to the analytical capabilities, (2) technical discussions of the chemical and instrumental technology applied for the analysis of aluminum, boron, calcium, carbon, chloride plus bromide, chromium, cobalt, copper, dysprosium, europium, fluoride, gadolinium, iron, magnesium, manganese, mercury, molybdenum, nickel, nitrogen, samarium, silicon, titanium, vanadium, thorium, and uranium (total, trace, and uranium VI), and (3) a formal presentation of the analytical procedures as applied to the LWBR Development Program. (U.S.)

On the Use of 233U-236U Double-Spike for TIMS Measurements of Uranium Isotopes: A Simulation Study

International Nuclear Information System (INIS)

Williams, R W

2004-01-01

Synthetic ion beams with instantaneous and temporal characteristics appropriate to thermal ionization mass spectrometry (TIMS) were mathematically generated and analyzed to determine the effects of using a mixed 233 U- 236 U spike (double-spike) in the analysis of uranium isotopes. The instantaneous beam characteristics are the intensities (e.g., counts per second) modeled with a Poisson distribution plus a component of random noise that simulates the detection processes. Several beam intensity and mass fractionation vs. time functions were modeled to simulate a range of sample sizes and the commonly employed methods of data collection. These beam profiles were also generated with different noise levels, and signal-to-noise vs. analytical precision diagrams are presented. Modeling focused on natural uranium, where 238 U/ 235 U = 137.88, and on the ability of a given method to determine precisely and accurately small variations in this ratio. Practical limits on precision were determined to be 20-30 ppm, which is consistent with precision seen for other elements by state-of-the-art TIMS. The TIMS total evaporation method was compared directly with the double-spike method. While similar analytical precisions are obtained with either method, the double-spike method of correcting for analytical bias gives more accurate results. The results of a total evaporation analysis will deviate from true by more than the analytical precision if as little as 0.05% of the signal is not integrated, whereas the accuracy and precision of the double-spiked analyses are always linked

Process technology for the molten-salt reactor 233U--Th cycle

International Nuclear Information System (INIS)

Hightower, J.R. Jr.

1975-01-01

After a brief description of the design features of the molten-salt breeder reactor, fuel processing for removal of 233 Pa and fission products is examined. Some recent developments in processing technology are discussed

Investigation of the fission yields of the fast neutron-induced fission of {sup 233}U; Mesure de la distribution en masse et en charge des produits de la fission rapide de l'{sup 233}U

Energy Technology Data Exchange (ETDEWEB)

Galy, J

1999-09-01

As a stars, a survey of the different methods of investigations of the fission product yields and the experimental data status have been studied, showing advantages and shortcomings for the different approaches. An overview of the existing models for the fission product distributions has been as well intended. The main part of this thesis was the measurement of the independent yields of the fast neutron-induced fission of{sup 233}U, never investigated before this work. The experiment has been carried out using the mass separator OSIRIS (Isotope Separator On-Line). Its integrated ion-source and its specific properties required an analysis of the delay-parameter and ionisation efficiency for each chemical species. On the other hand, this technique allows measurement of independent yields and cumulative yields for elements from Cu to Ba, covering most of the fission yield distribution. Thus, we measured about 180 independent yields from Zn (Z=30) to Sr (Z=38) in the mass range A=74-99 and from Pd (Z=46) to Ba (Z=56) in the mass range A=113-147, including many isomeric states. An additional experiment using direct {gamma}-spectroscopy of aggregates of fission products was used to determine more than 50 cumulative yields of element with half-life from 15 min to a several days. All experimental data have been compared to estimates from a semi-empirical model, to calculated values and to evaluated values from the European library JEF 2.2. Furthermore, a study of both thermal and fast neutron-induced fission of {sup 233}U measured at Studsvik, the comparison of the OSIRIS and LOHENGRIN facilities and the trends in new data for the Reactors Physics have been discussed. (author)

Analysis of a sustainable gas cooled fast breeder reactor concept

International Nuclear Information System (INIS)

Kumar, Akansha; Chirayath, Sunil S.; Tsvetkov, Pavel V.

2014-01-01

Highlights: • A Thorium-GFBR breeder for actinide recycling ability, and thorium fuel feasibility. • A mixture of 232 Th and 233 U is used as fuel and LWR used fuel is used. • Detailed neutronics, fuel cycle, and thermal-hydraulics analysis has been presented. • Run this TGFBR for 20 years with breeding of 239 Pu and 233 U. • Neutronics analysis using MCNP and Brayton cycle for energy conversion are used. - Abstract: Analysis of a thorium fuelled gas cooled fast breeder reactor (TGFBR) concept has been done to demonstrate the self-sustainability, breeding capability, actinide recycling ability, and thorium fuel feasibility. Simultaneous use of 232 Th and used fuel from light water reactor in the core has been considered. Results obtained confirm the core neutron spectrum dominates in an intermediate energy range (peak at 100 keV) similar to that seen in a fast breeder reactor. The conceptual design achieves a breeding ratio of 1.034 and an average fuel burnup of 74.5 (GWd)/(MTHM) . TGFBR concept is to address the eventual shortage of 235 U and nuclear waste management issues. A mixture of thorium and uranium ( 232 Th + 233 U) is used as fuel and light water reactor used fuel is utilized as blanket, for the breeding of 239 Pu. Initial feed of 233 U has to be obtained from thorium based reactors; even though there are no thorium breeders to breed 233 U a theoretical evaluation has been used to derive the data for the source of 233 U. Reactor calculations have been performed with Monte Carlo radiation transport code, MCNP/MCNPX. It is determined that this reactor has to be fuelled once every 5 years assuming the design thermal power output as 445 MW. Detailed analysis of control rod worth has been performed and different reactivity coefficients have been evaluated as part of the safety analysis. The TGFBR concept demonstrates the sustainability of thorium, viability of 233 U as an alternate to 235 U and an alternate use for light water reactor used fuel as a

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.

Overview of the recovery and processing of 233U from the Oak Ridge molten salt reactor experiment (MSRE) remediation activities

International Nuclear Information System (INIS)

Del Cul, G.D.; Icenhour, A.S.; Simmons, D.W.; Trowbridge, L.D.; Williams, D.F.; Toth, L.M.; Dai, S.

2001-01-01

The Molten Salt Reactor Experiment (MSRE) was operated at Oak Ridge National Laboratory (ORNL) from 1965 to 1969 to test the concept of a high-temperature, homogeneous, fluid-fueled reactor. The discovery that UF 6 and F 2 migrated from the storage tanks into distant pipes and a charcoal bed resulted in significant activities to remove and recover the 233 U and to decommission the reactor. The recovered fissile uranium will be converted into uranium oxide (U 3 O 8 ), which is a suitable form for long-term storage. This publication reports the research and several new developments that were needed to carry out these unique activities. (author)

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.

Los Alamos National Laboratory Site Integrated Management plan, uranium 233 storage and disposition. Volume 1: Project scope and description

International Nuclear Information System (INIS)

Nielsen, J.B.; Erickson, R.

1997-01-01

This Site Integration Management plan provides the Los Alamos Response to the Defense Nuclear Facility Safety Board (DNFSB) Recommendation 97-1. This recommendation addresses the safe storage and management of the Departments uranium 233 ( 233 U) inventory. In the past, Los Alamos has used 233 U for a variety of different weapons related projects. The material was used at a variety of sites in varying quantities. Now, there is a limited need for this material and the emphasis has shifted from use to storage and disposition of the material. The Los Alamos program to address the DNFSB Recommendation 97-1 has two emphases. First, take corrective action to address near term deficiencies required to provide safe interim storage of 233 U. Second, provide a plan to address long term storage and disposition of excess inventory at Los Alamos

Fission Cross-section Measurements of (233)U, (245)Cm and (241,243)Am at CERN n_TOF Facility

CERN Document Server

Calviani, M; Andriamonje, S; Chiaveri, E; Vlachoudis, V; Colonna, N; Meaze, M H; Marrone, S; Tagliente, G; Terlizzi, R; Belloni, F; Abbondanno, U; Fujii, K; Milazzo, P M; Moreau, C; Aerts, G; Berthoumieux, E; Dridi, W; Gunsing, F; Pancin, J; Perrot, L; Plukis, A; Alvarez, H; Duran, I; Paradela, C; Alvarez-Velarde, F; Cano-Ott, D; Gonzalez-Romero, E; Guerrero, C; Martinez, T; Villamarin, D; Vicente, M C; Andrzejewski, J; Marganiec, J; Assimakopoulos, P; Karadimos, D; Karamanis, D; Papachristodoulou, C; Patronis, N; Audouin, L; David, S; Ferrant, L; Isaev, S; Stephan, C; Tassan-Got, L; Badurek, G; Jericha, E; Leeb, H; Oberhummer, H; Pigni, M T; Baumann, P; Kerveno, M; Lukic, S; Rudolf, G; Becvar, F; Krticka, M; Calvino, F; Capote, R; Carrillo De Albornoz, A; Marques, L; Salgado, J; Tavora, L; Vaz, P; Cennini, P; Dahlfors, M; Ferrari, A; Gramegna, F; Herrera-Martinez, A; Kadi, Y; Mastinu, P; Praena, J; Sarchiapone, L; Wendler, H; Chepel, V; Ferreira-Marques, R; Goncalves, I; Lindote, A; Lopes, I; Neves, F; Cortes, G; Poch, A; Pretel, C; Couture, A; Cox, J; O'brien, S; Wiescher, M; Dillman, I; Heil, M; Kappeler, F; Mosconi, M; Plag, R; Voss, F; Walter, S; Wisshak, K; Dolfini, R; Rubbia, C; Domingo-Pardo, C; Tain, J L; Eleftheriadis, C; Savvidis, I; Frais-Koelbl, H; Griesmayer, E; Furman, W; Konovalov, V; Goverdovski, A; Ketlerov, V; Haas, B; Haight, R; Reifarth, R; Igashira, M; Koehler, P; Kossionides, E; Lampoudis, C; Lozano, M; Quesada, J; Massimi, C; Vannini, G; Mengoni, A; Oshima, M; Papadopoulos, C; Vlastou, R; Pavlik, A; Pavlopoulos, P; Plompen, A; Rullhusen, P; Rauscher, T; Rosetti, M; Ventura, A

2011-01-01

Neutron-induced fission cross-sections of minor actinides have been measured using the n_TOF white neutron source at CERN, Geneva, as part of a large experimental program aiming at collecting new data relevant for nuclear astrophysics and for the design of advanced reactor systems. The measurements at n_TOF take advantage of the innovative features of the n_TOF facility, namely the wide energy range, high instantaneous neutron flux and good energy resolution. Final results on the fission cross-section of 233U, 245Cm and 243Am from thermal to 20 MeV are here reported, together with preliminary results for 241Am. The measurement have been performed with a dedicated Fast Ionization Chamber (FIC), a fission fragment detector with a very high efficiency, relative to the very well known cross-section of 235U, measured simultaneously with the same detector.

Measurements of the prompt neutron spectra in 233U, 235U, 239Pu thermal neutron fission in the energy range of 0.01-5 MeV and in 252Cf spontaneous fission in the energy range of 0.01-10 MeV

International Nuclear Information System (INIS)

Starostov, B.I.; Semenov, A.F.; Nefedov, V.N.

1978-01-01

The measurement results on the prompt neutron spectra in 233 U, 235 U, 239 Pu thermal neutron fission in the energy range of 0.01-5 MeV and in 252 Cf spontaneous fission in the energy range of 0.01-10 MeV are presented. The time-of-flight method was used. The exceeding of the spectra over the Maxwell distributions is observed at E 252 Cf neutron fission spectra. The spectra analysis was performed after normalization of the spectra and corresponding Maxwell distributions for one and the same area. In the range of 0.05-0.22 MeV the yield of 235 U + nsub(t) fission neutrons is approximately 8 and approximately 15 % greater than the yield of 252 Cf and 239 Pu + nsub(t) fission neutrons, respectively. In the range of 0.3-1.2 MeV the yield of 235 U + nsub(t) fission neutrons is 8 % greater than the fission neutron yield in case of 239 Pu + nsub(t) fission. The 235 U + nsub(t) and 233 U + nsub(t) fission neutron spectra do not differ from one another in the 0.05-0.6 MeV range

Uranium-233 analysis of biological samples

International Nuclear Information System (INIS)

Gies, R.A.; Ballou, J.E.; Case, A.C.

1979-01-01

Two liquid scintillation techniques were compared for 233 U analysis: a two-phase extraction system (D2EHPA) developed by Keough and Powers, 1970, for Pu analysis; and a single-phase emulsion system (TT21) that holds the total sample in suspension with the scintillator. The first system (D2EHPA) was superior in reducing background (two- to threefold) and in accommodating a larger sample volume (fivefold). Samples containing > 50 mg/ml of slats were not extracted quantitatively by D2EHPA

Alecto - results obtained with homogeneous critical experiments on plutonium 239, uranium 235 and uranium 233; Alecto - resultats des experiences critiques homogenes realisees sur le plutonium 239, l'uranium 235 et l'uranium 233

Energy Technology Data Exchange (ETDEWEB)

Bruna, J G; Brunet, J P; Caizegues, R; Clouet d' Orval, Ch; Kremser, J; Tellier, H; Verriere, Ph [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-07-01

In this report are given the results of the homogeneous critical experiments ALECTO, made on plutonium 239, uranium 235 and uranium 233. After a brief description of the equipment, the critical masses for cylinders of diameters varying from 25 to 42 cm, are given and compared with other values (foreign results, criticality guide). With respect to the specific conditions of neutron reflection in the ALECTO experiments the minimal values of critical masses are: Pu239 M{sub c} = 910 {+-} 10 g, U235 M{sub c} = 1180 {+-} 12 g and U233 M{sub c} = 960 {+-} 10 g. Experiments relating to cross sections and constants to be used on these materials are presented. Lastly, kinetic experiments allow to compare pulsed neutron methods to fluctuation methods. [French] On presente dans ce rapport les resultats des experiences critiques homogenes ALECTO, effectuees sur le plutonium 239, l'uranium 235 et l'uranium 233. Apres avoir rappele la description des installations, on donne les masses critiques pour des cylindres de diametres variant entre 25 et 42 cm, qui sont comparees avec d'autres chiffres (resultats etrangers, guide de criticite). Dans les gammes des diametres etudies pour des cuves a fond plat reflechies lateralement, la valeur minimale des masses critiques est la suivante: Pu239 M{sub c} = 910 {+-} 10 g, U235 M{sub c} = 1180 {+-} 12 g et U233 M{sub c} 960 {+-} 10 g. Des experiences portant sur les sections efficaces et les constantes a utiliser sur ces milieux sont ensuite presentees. Enfin des experiences de cinetique permettent une comparaison entre la methode des neutrons pulses et la methode des fluctuations. (auteur)

Remote fabrication of (Th, {sup 233}U)O{sub 2} pellet-type fuels for CANDU reactors

Energy Technology Data Exchange (ETDEWEB)

Feraday, M A

1981-05-15

Thorium fuels enriched with {sup 233}U must be fabricated in shielded cells because of high gamma and alpha activity. A conceptual design of a remotely operated plant to produce gamma-active pellet fuels has been made. The plant consists of eight fabrication canyons, two repair canyons, and several miscellaneous cells. Process equipment is modular, easily disconnected, and mounted on plates for easy removal. Equipment consists of a combination of robotics, hard automation, and conventional process equipment. The plant is operated from a central control room with the assistance of a sophisticated computer-based control and information system. Many of the automated process steps are preprogrammed on the control computer and executed on demand by the supervising operator. The technology to build such a plant exists today but needs to be adapted to the needs of the recycle fuel industry. (author)

Retention and translocation of inhaled uranyl nitrate (233U and 232U) in rats

International Nuclear Information System (INIS)

Ballou, J.E.; Gies, R.A.; Wogman, N.A.

1978-01-01

The uranium-thorium breeder reactors proposed for nuclear power production, and other thorium fuel systems in conventional reactors, utilize fuels and fuel recycle process solutions that have not been evaluated for biological hazard. This project emphasizes studies of the metabolism of the oxide fuels and the nitrate solutions of the major radionuclides, following inhalation, ingestion, or cutaneous application in rodents. Preliminary data are reported for the clearance of inhaled 233 UO 2 (NO 3 ) 2 and 232 UO 2 (NO 3 ) 2 from the lung and their translocation to skeleton

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...

15 CFR 23.3 - Plan.

Science.gov (United States)

2010-01-01

... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Plan. 23.3 Section 23.3 Commerce and... MISSING CHILDREN § 23.3 Plan. (a) The Department of Commerce will supplement and expand the national... biannual meetings of departmental representatives to discuss the current plan and recommendations for...

Migration of uranium process wastes from the uranium-233--thorium-232 cycle

International Nuclear Information System (INIS)

Fried, S.; Sabau, C.; Hines, J.; Friedman, A.

1978-03-01

With the advent of fuel loadings of 233 U in the Shippingport Reactor, it has become important to understand the migratory behavior of uranium. The purpose of this study is the determination of the parameters influencing the migration of U(VI), the most likely chemical form of uranium to be mobilized from a repository. Samples of rhyolite tuff were used to measure the absorption coefficients of solutions of U(VI) in ground waters. In addition, columns of tuff were used to measure the elution behavior of U(VI) at various conditions of pH, U(VI) concentration, and flow saturation. These results indicate that there are several elution peaks with values of K/sub d/ between 35 and 120. This behavior is not the same as that of Pu(VI) on tuff; and the experimental results to date have not revealed the reason for this difference. Values of K/sub d/ in this range imply that geological containment would be difficult in strata of this type. It may be possible to find more retentive strata than tuff. Rocks containing reducing components are the most likely candidates and further investigation is urgently needed if the 233 U-Th cycle is to be widely used

49 CFR 233.9 - Reports.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Reports. 233.9 Section 233.9 Transportation Other... TRANSPORTATION SIGNAL SYSTEMS REPORTING REQUIREMENTS § 233.9 Reports. Not later than April 1, 1997 and every 5 years thereafter, each carrier shall file with FRA a signal system status report “Signal System Five...

[Status of traditional Chinese medicine materials seed and seedling breeding bases].

Science.gov (United States)

Li, Ying; Huang, Lu-Qi; Zhang, Xiao-Bo; Wang, Hui; Cheng, Meng; Zhang, Tian; Yang, Guang

2017-11-01

Seeds and seedlings are the material basis of traditional Chinese medicine materials production, and the construction of traditional Chinese medicine materials seed and seedling breeding bases is beneficial to the production of high-quality traditional Chinese medicine materials. The construction of traditional Chinese medicine materials seed and seedling breeding bases is one of the major topics of Chinese medica resources census pilot. Targets, tasks of traditional Chinese medicine materials seed and seedling breeding bases based on Chinese medica resources census pilot were expounded.Construction progress including hardware construction, germplasm conservation and breeding, procedures and standardsestablishment, social servicesare presented. Development counter measures were proposed for the next step: perfect the standard and system, maintain and strengthen the breeding function, strengthen the cultivation of multi-level talents, explore market development model, joint efforts to deepen services and development. Copyright© by the Chinese Pharmaceutical Association.

39 CFR 233.5 - Requesting financial records from a financial institution.

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2010-07-01

... INSPECTION SERVICE AUTHORITY § 233.5 Requesting financial records from a financial institution. (a... Department of the U.S. Postal Service to request financial records from a financial institution pursuant to... authorized to request financial records of any customer from a financial institution pursuant to a formal...

40 CFR 233.31 - Coordination requirements.

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2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Coordination requirements. 233.31 Section 233.31 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING 404 STATE PROGRAM REGULATIONS Program Operation § 233.31 Coordination requirements. (a) If a proposed...

Breeding and plutonium characterization analysis on actinides closed water-cooled thorium reactor

International Nuclear Information System (INIS)

Permana, Sidik; Sekimoto, Hiroshi; Takaki, Naoyuki

2009-01-01

Higher difficulties (barrier) or more complex design of nuclear weapon, material fabrication and handling and isotopic enrichment can be achieved by a higher isotopic barrier. The isotopic material barrier includes critical mass, heat-generation rate, spontaneous neutron generation and radiation. Those isotopic barriers in case of plutonium isotope is strongly depend on the even mass number of plutonium isotope such as 238 Pu, 240 Pu and 242 Pu and for 233 U of thorium cycle depends on 232 U. In this present study, fuel sustainability as fuel breeding capability and plutonium characterization as main focus of proliferation resistance analysis have been analyzed. Minor actinide (MA) is used as doping material to be loaded into the reactors with thorium fuel. Basic design parameters are based on actinide closed-cycle reactor cooled by heavy water. The evaluation use equilibrium burnup analysis coupled with cell calculation of SRAC and nuclear data library is JENDL.32. Parametrical survey has been done to analyze the effect of MA doping rate, different moderation ratio for several equilibrium burnup cases. Plutonium characterization which based on plutonium isotope composition is strongly depending on MA doping concentration and different moderation conditions. Breeding condition can be achieved and high proliferation resistance level can be obtained by the present reactor systems. Higher isotopic plutonium composition of Pu-238 (more than 40%) can be obtained compared with other plutonium isotopes. In addition, higher moderation ratio gives the isotope composition of 238 Pu increases, however, it obtains lower composition when MA doping is increased and it slightly lower composition for higher burnup. Meanwhile, higher 240 Pu composition can be achieved by higher MA doping rate as well as for obtaining higher breeding capability. (author)

Mass determination of U-233 and Pu-239 by gamma spectrometry technique

International Nuclear Information System (INIS)

Moraes, M.A.P.V. de; Pugliesi, R.

1988-09-01

The gamma spectrometry technique has been used for masses determinations of uranium-233 and plutonium-239, granted by AERE-HARWELL. A high purity Ge semicondutor detector was used and the total efficiency curve was obtained for the counting system in the energy range 13 KeV to 135 KeV. The calculated values for the masses compared with that obtained by means of gravimetry technique. (author) [pt

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

7 CFR 58.233 - Skim milk.

Science.gov (United States)

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Skim milk. 58.233 Section 58.233 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Materials § 58.233 Skim milk. The skim milk shall be separated from whole milk meeting the requirements as...

Gas core reactor power plants designed for low proliferation potential

International Nuclear Information System (INIS)

Lowry, L.L.

1977-09-01

The feasibility of gas core nuclear power plants to provide adequate power while maintaining a low inventory and low divertability of fissile material is studied. Four concepts were examined. Two used a mixture of UF 6 and helium in the reactor cavities, and two used a uranium-argon plasma, held away from the walls by vortex buffer confinement. Power levels varied from 200 to 2500 MWth. Power plant subsystems were sized to determine their fissile material inventories. All reactors ran, with a breeding ratio of unity, on 233 U born from thorium. Fission product removal was continuous. Newly born 233 U was removed continuously from the breeding blanket and returned to the reactor cavities. The 2500-MWth power plant contained a total of 191 kg of 233 U. Less than 4 kg could be diverted before the reactor shut down. The plasma reactor power plants had smaller inventories. In general, inventories were about a factor of 10 less than those in current U.S. power reactors

49 CFR 233.11 - Civil penalties.

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2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Civil penalties. 233.11 Section 233.11..., DEPARTMENT OF TRANSPORTATION SIGNAL SYSTEMS REPORTING REQUIREMENTS § 233.11 Civil penalties. Any person (an... subject to a civil penalty of at least $650 and not more than $25,000 per violation, except that...

Interim report on core physics and fuel cycle analysis of the pebble bed reactor power plant concept

International Nuclear Information System (INIS)

Vondy, D.R.

1977-12-01

Calculations were made to predict the performance of a pebble bed reactor operated in a mode to produce fissile fuel (high conversion or breeding). Both a one pebble design and a design involving large primary feed pebbles and small fertile pebbles were considered. A relatively short residence time of the primary pebbles loaded with 233 U fuel was found to be necessary to achieve a high breeding ratio, but this leads to relatively high fuel costs. A high fissile inventory is associated with a low C/Th ratio and a high thorium loading, causing the doubling time to be long, even though the breeding ratio is high, and the fuel cost of electrical product to be high. Production of 233 U fuel from 235 U feed was studied and performances of the converter and breeder reactor concepts were examined varying the key parameters

Factors determining presence of passerines breeding within White Stork Ciconia ciconia nests

Science.gov (United States)

Zbyryt, Adam; Jakubas, Dariusz; Tobolka, Marcin

2017-10-01

Nests of White Stork Ciconia ciconia are commonly used by various passerines as nesting sites. In this study, we investigated factors determining presence and number of pairs of species breeding within White Stork nests in an extensive farmland in NE Poland. In 133 (57%) out of 233 White Stork nests, we found at least one breeding pair of passerine bird. These were from three species: House Sparrows Passer domesticus (68% of 133 nests with co-breeding), Tree Sparrows Passer montanus (65%), and Starlings Sturnus vulgaris (30%). The probability of breeding passerines within White Stork nests increased with increasing nest thickness, and was significantly higher in currently occupied nests. Sparrows were more likely to breed in White Stork nests located on electricity poles, situated closer to settlements and surrounded mainly by arable fields where meadows were not prevalent. In this paper, we show that White Stork nests are favorable nesting sites for passerines, as they are well insulated and provide an anti-predatory shield.

Factors determining presence of passerines breeding within White Stork Ciconia ciconia nests.

Science.gov (United States)

Zbyryt, Adam; Jakubas, Dariusz; Tobolka, Marcin

2017-08-18

Nests of White Stork Ciconia ciconia are commonly used by various passerines as nesting sites. In this study, we investigated factors determining presence and number of pairs of species breeding within White Stork nests in an extensive farmland in NE Poland. In 133 (57%) out of 233 White Stork nests, we found at least one breeding pair of passerine bird. These were from three species: House Sparrows Passer domesticus (68% of 133 nests with co-breeding), Tree Sparrows Passer montanus (65%), and Starlings Sturnus vulgaris (30%). The probability of breeding passerines within White Stork nests increased with increasing nest thickness, and was significantly higher in currently occupied nests. Sparrows were more likely to breed in White Stork nests located on electricity poles, situated closer to settlements and surrounded mainly by arable fields where meadows were not prevalent. In this paper, we show that White Stork nests are favorable nesting sites for passerines, as they are well insulated and provide an anti-predatory shield.

Dissolution of unirradiated UO{sub 2} and UO{sub 2} doped with {sup 233}U under reducing conditions

Energy Technology Data Exchange (ETDEWEB)

Ollila, K. [VTT Processes (Finland); Oversby, V.M. [VMO Konsult (Sweden)

2005-01-01

Experiments have been conducted to determine an upper limit to the dissolution rate of UO{sub 2} under reducing conditions appropriate to those in a geologic repository for spent fuel disposal in Finland and Sweden. Test duration ranged from 52 to 140 days. The total amount of U recovered in each test was converted into a dissolution rate per year for the sample. The dissolution rate was then used to calculate an expected lifetime for the samples under the test conditions. The dissolution rate did not depend on the length of the testing period. Rather, the dissolution rate appeared to decrease as the samples were exposed to sequential testing periods. This indicates that the results are still influenced by transient effects such as high-energy surface sites, which implies that the dissolution rates measured are upper limits. The sample lifetimes calculated from the last two testing periods, which had a total of 269 days, ranged from 7 to 10 million years. There was no indication of an effect of alpha radiolysis on the dissolution rate results for samples with doping levels of 0, 5, and 10% {sup 233}U.

Alecto - results obtained with homogeneous critical experiments on plutonium 239, uranium 235 and uranium 233

International Nuclear Information System (INIS)

Bruna, J.G.; Brunet, J.P.; Caizegues, R.; Clouet d'Orval, Ch.; Kremser, J.; Tellier, H.; Verriere, Ph.

1965-01-01

In this report are given the results of the homogeneous critical experiments ALECTO, made on plutonium 239, uranium 235 and uranium 233. After a brief description of the equipment, the critical masses for cylinders of diameters varying from 25 to 42 cm, are given and compared with other values (foreign results, criticality guide). With respect to the specific conditions of neutron reflection in the ALECTO experiments the minimal values of critical masses are: Pu239 M c = 910 ± 10 g, U235 M c = 1180 ± 12 g and U233 M c = 960 ± 10 g. Experiments relating to cross sections and constants to be used on these materials are presented. Lastly, kinetic experiments allow to compare pulsed neutron methods to fluctuation methods [fr

Study on the thorium-based breeder with molten fluoride salt blanket in the Nuclear Hot Spring - 5420

International Nuclear Information System (INIS)

Bing, X.; Yingzhong, L.

2015-01-01

Nuclear Hot Spring (NHS) is an innovative reactor type featured by pool-type molten-salt-cooled pebble-bed reactor core with the capability of natural circulation under full power operation. Except for the potential applications in power generation and high temperature process heat, thorium-based breeding is also a promising feature of the NHS. In order to take advantage of both the highly inherent safety and the on-line processing capability of fluid thorium-based fuels, a breeder design of NHS equipped with a blanket of molten salt with thorium fluoride outside the pebble-bed core is proposed in this work. For the purpose of keeping cleanness of the primary loop and blanket loop, both loops are isolated physically from each other, and the rapid on-line extraction of converted 233 Pa and 233 U is employed for the processing of blanket salt. The conversion ratio, defined as the ratio of converted 233 Pa and 233 U to the consumed fissile uranium in seed fuels, is investigated by varying the relevant parameters such as the circulation flux of blanket salt and the discharge burn-up of seed fuels. It is found that breeding can be achieved for the pure 233 U seed scheme with relatively low discharge burn-up and low blanket salt flux. However, the reprocessing for the HTGR fuels with TRISO particles has to be taken into account to ensure the breeding. (authors)

Impact on breeding rate of different Molten Salt reactor core structures

International Nuclear Information System (INIS)

Wang Haiwei; Mei Longwei; Cai Xiangzhou; Chen Jingen; Guo Wei; Jiang Dazhen

2013-01-01

Background: Molten Salt Reactor (MSR) has several advantages over the other Generation IV reactor. Referred to the French CNRS research and compared to the fast reactor, super epithermal neutron spectrum reactor type is slightly lower and beading rate reaches 1.002. Purpose: The aim is to explore the best conversion zone layout scheme in the super epithermal neutron spectrum reactor. This study can make nuclear fuel as one way to solve the energy problems of mankind in future. Methods: Firstly, SCALE program is used for molten salt reactor graphite channel, molten salt core structure, control rods, graphite reflector and layer cladding structure. And the SMART modules are used to record the important actinides isotopes and their related reaction values of each reaction channel. Secondly, the thorium-uranium conversion rate is calculated. Finally, the better molten salt reactor core optimum layout scheme is studied comparing with various beading rates. Results: Breading zone layout scheme has an important influence on the breading rate of MSR. Central graphite channels in the core can get higher neutron flux irradiation. And more 233 Th can convert to 233 Pa, which then undergoes beta decay to become 233 U. The graphite in the breading zone gets much lower neutron flux irradiation, so the life span of this graphite can be much longer than that of others. Because neutron flux irradiation in the uranium molten salt graphite has nearly 10 times higher than the graphite in the breading zone, it has great impact on the thorium-uranium conversion rates. For the super epithermal neutron spectrum molten salt reactors, double salt design cannot get higher thorium-uranium conversion rates. The single molten salt can get the same thorium-uranium conversion rate, meanwhile it can greatly extend the life of graphite in the core. Conclusions: From the analysis of calculation results, Blanket breeding area in different locations in the core can change the breeding rates of thorium

Nuclear performance optimization of the Be/Li/Th blanket for the fusion breeder

International Nuclear Information System (INIS)

Lee, J.D.; Bandini, B.R.

1985-01-01

More rigorous nuclear analysis, including treatment of resonance self-shielding effects coupled with an optimization procedure, has resulted in improved performance of the Be/Li/Th blanket. Net U-233 breeding ratio has increased 36% (to 0.84) while at an average U-233/Th ratio of 0.5 a/o average energy multiplication has increased only 12% (to 2.1) compared with earlier results

Within the framework of the new fuel cycle 232Th/233U, determination of the 233Pa(n.γ) radiative capture cross section for neutron energies ranging between 0 and 1 MeV

International Nuclear Information System (INIS)

Boyer, S.

2004-10-01

The Thorium cycle Th 232 /U 233 may face brilliant perspectives through advanced concepts like molten salt reactors or accelerator driven systems but it lacks accurate nuclear data concerning some nuclei. Pa 233 is one of these nuclei, its high activity makes the direct measurement of its radiative neutron capture cross-section almost impossible. This difficulty has been evaded by considering the transfer reaction Th 232 (He 3 ,p)Pa 234 * in which the Pa 234 nucleus is produced in various excited states according to the amount of energy available in the reaction. The first chapter deals with the thorium cycle and its assets to contribute to the quenching of the fast growing world energy demand. The second chapter gives a detailed description of the experimental setting. A scintillation detector based on deuterated benzene (C 6 D 6 ) has been used to counter gamma ray cascades. The third chapter is dedicated to data analysis. In the last chapter we compare our experimental results with ENDF and JENDL data and with computed values from 2 statistical models in the 0-1 MeV neutron energy range. Our results disagree clearly with evaluated data: our values are always above ENDF and JENDL data but tend to near computed values. We have also perform the measurement of the radiative neutron cross-section of Pa 231 for a 110 keV neutron: σ(n,γ) 2.00 ± 0.14 barn. (A.C.)

Vulnerability of breeding waterbirds to climate change in the Prairie Pothole Region, U.S.A.

Directory of Open Access Journals (Sweden)

Valerie Steen

Full Text Available The Prairie Pothole Region (PPR of the north-central U.S. and south-central Canada contains millions of small prairie wetlands that provide critical habitat to many migrating and breeding waterbirds. Due to their small size and the relatively dry climate of the region, these wetlands are considered at high risk for negative climate change effects as temperatures increase. To estimate the potential impacts of climate change on breeding waterbirds, we predicted current and future distributions of species common in the PPR using species distribution models (SDMs. We created regional-scale SDMs for the U.S. PPR using Breeding Bird Survey occurrence records for 1971-2011 and wetland, upland, and climate variables. For each species, we predicted current distribution based on climate records for 1981-2000 and projected future distributions to climate scenarios for 2040-2049. Species were projected to, on average, lose almost half their current habitat (-46%. However, individual species projections varied widely, from +8% (Upland Sandpiper to -100% (Wilson's Snipe. Variable importance ranks indicated that land cover (wetland and upland variables were generally more important than climate variables in predicting species distributions. However, climate variables were relatively more important during a drought period. Projected distributions of species responses to climate change contracted within current areas of distribution rather than shifting. Given the large variation in species-level impacts, we suggest that climate change mitigation efforts focus on species projected to be the most vulnerable by enacting targeted wetland management, easement acquisition, and restoration efforts.

Study of the desintegration of short-life fission products. Application to the mass distribution in the fission of 238U and 233U induced by 14MeV neutrons

International Nuclear Information System (INIS)

Cavallini, Pierre.

1975-01-01

Nuclear spectrometry of short-life fission products was investigated, together with direct applications to the study of mass and charge distribution in fission reactions. It is shown that, by choosing judiciously the target in which the fission product is created and owing to the differences in stabilities and evaporation temperatures of the compounds obtained, it is possible to separate some elements. For example, niobium was separated by heating after irradiation of a mixture of UC and RuCl 3 , and sublimation in a tube with temperature gradient. It was thus possible to study the 99 Nb isotope. Other classical chemical separation processes were used for yttrium and strontium. The half-lifes beta and gamma spectra, decay schemes of 93 Sr, 94 Y and 95 Y were studied. It was shown how to obtain mass distribution in fission using a nondestructive gamma analysis method. As an application, results obtained in the fission of 233 U and 238 U at 14 MeV are given [fr

40 CFR 233.4 - Conflict of interest.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Conflict of interest. 233.4 Section 233.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING 404 STATE PROGRAM REGULATIONS General § 233.4 Conflict of interest. Any public officer or employee who has a direct...

10 CFR 600.233 - Supplies.

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2010-01-01

... supplies exceeding $5,000 in total aggregate fair market value upon termination or completion of the award... 10 Energy 4 2010-01-01 2010-01-01 false Supplies. 600.233 Section 600.233 Energy DEPARTMENT OF... Supplies. (a) Title. Title to supplies acquired under a grant or subgrant will vest, upon acquisition, in...

45 CFR 233.52 - Overpayment to aliens.

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2010-10-01

... 45 Public Welfare 2 2010-10-01 2010-10-01 false Overpayment to aliens. 233.52 Section 233.52... ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.52 Overpayment to aliens. A State Plan under title IV-A of the Social Security Act, shall provide that: (a) Any sponsor of an alien and the alien shall be...

233S Decommissioning Project Environmental Control Plan

International Nuclear Information System (INIS)

Zoric, J.P.

2000-01-01

This Environmental Control Plan is for the 233S Decommissioning activities conducted under the removal action report for the 233S Decontamination and Demolition Project. The purpose of this ECP is to identify environmental requirements for the 233S project. The ECP is a compilation of existing environmental permit conditions, regulatory requirements, and environmental requirements applicable to the specific project or functional activity

Burnup characteristics of binary breeder reactors

International Nuclear Information System (INIS)

Dias, A.F.; Nascimento, J.A. do; Ishiguro, Y.

1983-01-01

Burnup calculations of a binary breeder reactor have been done for two cases of fueling. In one case the U 233 /TH fueled inner core and the Pu/U-fueled outer core have the same number of fuel assemblies. In the other case two outermost rings in the inner core are Pu/U-fueled. The second case is considered for an initial phase of thorim cycle introduction when the supply of U 233 could be limited. Results show an efficient breeding on the thorium cycle in both cases. (Author) [pt

Within the framework of the new fuel cycle {sup 232}Th/{sup 233}U, determination of the {sup 233}Pa(n.{gamma}) radiative capture cross section for neutron energies ranging between 0 and 1 MeV; Dans le cadre du nouveau cycle de combustible {sup 232}Th/{sup 233}U, determination de la section efficace de capture radiative {sup 233}Pa(n,{gamma}) pour des energies de neutrons comprises entre 0 et 1 MeV

Energy Technology Data Exchange (ETDEWEB)

Boyer, S

2004-10-15

The Thorium cycle Th{sup 232}/U{sup 233} may face brilliant perspectives through advanced concepts like molten salt reactors or accelerator driven systems but it lacks accurate nuclear data concerning some nuclei. Pa{sup 233} is one of these nuclei, its high activity makes the direct measurement of its radiative neutron capture cross-section almost impossible. This difficulty has been evaded by considering the transfer reaction Th{sup 232}(He{sup 3},p)Pa{sup 234}* in which the Pa{sup 234} nucleus is produced in various excited states according to the amount of energy available in the reaction. The first chapter deals with the thorium cycle and its assets to contribute to the quenching of the fast growing world energy demand. The second chapter gives a detailed description of the experimental setting. A scintillation detector based on deuterated benzene (C{sub 6}D{sub 6}) has been used to counter gamma ray cascades. The third chapter is dedicated to data analysis. In the last chapter we compare our experimental results with ENDF and JENDL data and with computed values from 2 statistical models in the 0-1 MeV neutron energy range. Our results disagree clearly with evaluated data: our values are always above ENDF and JENDL data but tend to near computed values. We have also perform the measurement of the radiative neutron cross-section of Pa{sup 231} for a 110 keV neutron: {sigma}(n,{gamma}) 2.00 {+-} 0.14 barn. (A.C.)

Consultants' Meeting on Review Benchmarking of Nuclear Data for the Th/U Fuel Cycle. Summary Report

International Nuclear Information System (INIS)

Capote Noy, R.

2011-02-01

A summary is given of the Consultants' Meeting (CM) on Review and Benchmarking of Nuclear Data for the Th/U Fuel Cycle. An IAEA Coordinated Research Project (CRP) on 'Nuclear Data for Th/U Fuel Cycle' was concluded in 2005. The CRP activities resulted in new evaluated nuclear data files for 232 Th, 231 , 233 Pa (later adopted for the ENDF/B-VII.0 library) and improvements to existing evaluations for 232 , 233 , 234 , 236 U. Available nuclear data evaluations for 230 - 232 Th, 231,233 Pa and 232 , 233 , 234 U were reviewed including ROSFOND2010, CENDL-3.1, JENDL-4, JEFF-3.1.1, MINSKACT, and ENDF/B-VII.0 libraries. Benchmark results of available evaluations for 232 Th and 233 U were also discussed. (author)

Dissolution rates of unirradiated UO{sub 2}, UO{sub 2} doped with {sup 233}U, and spent fuel under normal atmospheric conditions and under reducing conditions using an isotope dilution method

Energy Technology Data Exchange (ETDEWEB)

Ollila, Kaija [VTT Processes, Helsinki (Finland); Albinsson, Yngve [Chalmers Univ. of Technology, Goeteborg (Sweden); Oversby, Virginia [VMO Konsult, Stockholm (Sweden); Cowper, Mark [AEA Technology, Harwell (United Kingdom)

2003-10-01

additional meaningful data. 8) A test procedure that used several short exposures of the sample to solution - the puff test procedure - gave results that showed very little recovery of the spike solution at the end of the tests. Only 10% of the {sup 235}U added as spike was recovered, indicating that 90% of the spike had precipitated onto the solid sample or the iron strip. 9) Tests of UO{sub 2} pellet materials containing {sup 233}U to provide an alpha decay activity similar to that expected for spent fuel 3000 and 10,000 years after disposal showed that the pellet materials behaved as expected under air atmosphere conditions, showing that the manufacturing method was successful. 10) Early testing of the {sup 233}U-doped materials under reducing conditions showed relatively rapid (30 minute) dissolution of small amounts of U at the start of the puff test procedure. Results of analyses of an acidified fraction of the same solutions after 1 or 2 weeks holding indicate that the solutions were inhomogeneous, indicating the presence of colloidal material or small grains of solid. 11) Samples from the {sup 233}U-doped tests initially indicated dissolution of solid during the first week of testing, with some indication of more rapid dissolution of the material with the higher doping. 12) The second cycle of testing of the {sup 233}U-doped materials also showed dissolution occurring during the dilution stages of the puff test. The subsequent week of testing also showed small amounts of further dissolution, with hints that the doped samples were dissolving faster than the undoped samples. 13) At the end of 2 weeks of cycle 2 the remaining solution and solid was transferred to a new reaction vessel, the solution was made up to original volume, and a new dose of spike was added. The results of analyses of [U] and isotopic composition show that the measured U is that expected from dilution of the original solution plus adding the spike. 14) Samples taken during 2 weeks of testing of

An optimized symbiotic fusion and molten-salt fission reactor system

International Nuclear Information System (INIS)

Blinkin, V.L.; Novikov, V.M.

A symbiotic fusion-fission reactor system which breeds nuclear fuel is discussed. In the blanket of the controlled thermonuclear reactor (CTR) uranium-233 is generated from thorium, which circulates in the form of ThF 4 mixed with molten sodium and beryllium fluorides. The molten-salt fission reactor (MSR) burns up the uranium-233 and generates tritium for the fusion reactor from lithium, which circulates in the form of LiF mixed with BeF 2 and 233 UF 4 through the MSR core. With a CTR-MSR thermal power ratio of 1:11 the system can produce electrical energy and breed fuel with a doubling time of 4-5 years. The system has the following special features: (1) Fuel reprocessing is much simpler and cheaper than for contemporary fission reactors; reprocessing consists simply in continuous removal of 233 U from the salt circulating in the CTR blanket by the fluorination method and removal of xenon from the MSR fuel salt by gas scavenging; the MSR fuel salt is periodically exchanged for fresh salt and the 233 U is then removed from it; (2) Tritium is produced in the fission reactor, which is a much simpler system than the fusion reactor; (3) The CTR blanket is almost ''clean''; no tritium is produced in it and fission fragment activity does not exceed the activity induced in the structural materials; (4) Almost all the thorium introduced into the CTR blanket can be used for producing 233 U

Critical Experiments With Aqueous Solutions of 233UO2(NO3)2

International Nuclear Information System (INIS)

Thomas, J.T.

2001-01-01

This report provides the critical experimenter's interpretations and descriptions of informal critical experiment logbook notes and associated information (e.g., experimental equipment designs/sketches, chemical and isotopic analyses, etc.) for the purpose of formally documenting the results of critical experiments performed in the late 1960s at the Oak Ridge Critical Experiments Facility. The experiments were conducted with aqueous solutions of 97.6 wt % 233 U uranyl nitrate having uranium densities varying between about 346 g U/l and 45 g U/l. Criticality was achieved with single simple units (e.g., cylinders and spheres) and with spaced subcritical simple cylindrical units arranged in unreflected, water-reflected, and polyethylene reflected critical arrays

Engineering evaluation/cost analysis for the 233-S Plutonium Concentration Facility

International Nuclear Information System (INIS)

Rugg, J.E.

1996-08-01

The 100, 200, 300 and 1100 Areas of the Hanford Site were placed on the U. S. Environmental Protection Agency's National Priorities List in November 1989 under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Located in the 200 Area is the deactivated 233-S Plutonium Concentration Facility (used in the REDOX process). The facility has undergone severe degradation due to exposure to extreme weather conditions. An expedited response is proposed to ensure protection of human health and the environment. The Department of Energy, Richland Operations Office (RL) in cooperation with the Washington State Department of Ecology, has prepared this Engineering Evaluation/Cost Analysis pursuant to CERCLA. Based on the evaluation, RL has determined that hazardous substances in the 233-S Facility may present a potential threat to human health or the environment, and that an expedited removal action is warranted for decommissioning of the facility

Comparative genetic diversity in a sample of pony breeds from the U.K. and North America: a case study in the conservation of global genetic resources.

Science.gov (United States)

Winton, Clare L; Plante, Yves; Hind, Pamela; McMahon, Robert; Hegarty, Matthew J; McEwan, Neil R; Davies-Morel, Mina C G; Morgan, Charly M; Powell, Wayne; Nash, Deborah M

2015-08-01

Most species exist as subdivided ex situ daughter population(s) derived from a single original group of individuals. Such subdivision occurs for many reasons both natural and manmade. Traditional British and Irish pony breeds were introduced to North America (U.S.A. and Canada) within the last 150 years, and subsequently equivalent breed societies were established. We have analyzed selected U.K. and North American equivalent pony populations as a case study for understanding the relationship between putative source and derived subpopulations. Diversity was measured using mitochondrial DNA and a panel of microsatellite markers. Genetic signatures differed between the North American subpopulations according to historical management processes. Founder effect and stochastic drift was apparent, particularly pronounced in some breeds, with evidence of admixture of imported mares of different North American breeds. This demonstrates the importance of analysis of subpopulations to facilitate understanding the genetic effects of past management practices and to lead to informed future conservation strategies.

Production and Reproduction Efficiency in Turcana and Ratca Sheep Breeds

Directory of Open Access Journals (Sweden)

Maria Sauer

2017-05-01

Full Text Available Aim of the current comparative study was to evaluate the production and reproduction efficiency in indigenous Turcana and endangered Ratca sheep breeds. Milk yield for the two breeds was on average 68.23±2.33 kg for Ratca ewes and 76.81±2.99 kg in Turcana, respectively, differences between two breeds were significant (p≤0.01. Conception rates were of 97.7±0.87% in Ratca and of 94.8±0.65% in Turcana ewes, respectively, differences were significant between the two flocks (p≤0.05, with the Ratca ewes achieving better fertility rates, compared to their counterparts, the Turcana breed. For prolificacy, the Turcana ewes outperformed significantly (p≤0.01 the Ratca, with an average litter size of 124.2±1.86% and 110.1±1.44%, respectively. Lambs survival and adult ewe culling rates were not affected by the breed factor (p>0.05. Adult ewes body weight when put to ram was significantly (p≤0.05 influenced by the breed, with Turcana ewes having on average 53.8±2.89 kg, compared to 48.0±3.22 kg for the Ratca ewes. The average farm yearly incomes were estimated to be of 150.32 EUR for Ratca ewe-unit and of 144.97 EUR for the Turcana ewe-unit. Although the Turcana outperformed the Ratca ewes, the annual revenue was higher for the Ratca, due to the state conservation subsidy for rare and endangered breeds.

Assembly-level analysis of heterogeneous Th–Pu PWR fuel

International Nuclear Information System (INIS)

Zainuddin, Nurjuanis Zara; Parks, Geoffrey T.; Shwageraus, Eugene

2017-01-01

Highlights: • We directly compare homogeneous and heterogeneous Th–Pu fuel. • Examine whether there is an increase in Pu incineration in the latter. • Homogeneous fuel was able to achieve much higher Pu incineration. • In the heterogeneous case, U-233 breeding is faster (larger power fraction), thus decreasing incineration of Pu. - Abstract: This study compares homogeneous and heterogeneous thorium–plutonium (Th–Pu) fuel assemblies (with high Pu content – 20 wt%), and examines whether there is an increase in Pu incineration in the latter. A seed-blanket configuration based on the Radkowsky thorium reactor concept is used for the heterogeneous assembly. This separates the thorium blanket from the uranium seed, or in this case a plutonium seed. The seed supplies neutrons to the subcritical thorium blanket which encourages the in situ breeding and burning of "2"3"3U, allowing the fuel to stay critical for longer, extending burnup of the fuel. While past work on Th–Pu seed-blanket units shows superior Pu incineration compared to conventional U–Pu mixed oxide fuel, there is no literature to date that directly compares the performance of homogeneous and heterogeneous Th–Pu assembly configurations. Use of exactly the same fuel loading for both configurations allows the effects of spatial separation to be fully understood. It was found that the homogeneous fuel with and without burnable poisons was able to achieve much higher Pu incinerations than the heterogeneous fuel configurations, while still attaining a reasonably high discharge burnup. This is because in the heterogeneous cases, "2"3"3U breeding is faster, thereby contributing to a much larger fraction of total power produced by the assembly. In contrast, "2"3"3U build-up is slower in the homogeneous case and therefore Pu burning is greater. This "2"3"3U begins to contribute a significant fraction of power produced only towards the end of life, thus extending criticality, allowing more Pu to

Power level effects on thorium-based fuels in pressure-tube heavy water reactors

Energy Technology Data Exchange (ETDEWEB)

Bromley, B.P.; Edwards, G.W.R., E-mail: blair.bromley@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Sambavalingam, P. [Univ. of Ontario Inst. of Technology, Oshawa, Ontario (Canada)

2016-06-15

Lattice and core physics modeling and calculations have been performed to quantify the impact of power/flux levels on the reactivity and achievable burnup for 35-element fuel bundles made with Pu/Th or U-233/Th. The fissile content in these bundles has been adjusted to produce on the order of 20 MWd/kg burnup in homogeneous cores in a 700 MWe-class pressure-tube heavy water reactor, operating on a once-through thorium cycle. Results demonstrate that the impact of the power/flux level is modest for Pu/Th fuels but significant for U-233/Th fuels. In particular, high power/flux reduces the breeding and burnup potential of U-233/Th fuels. Thus, there may be an incentive to operate reactors with U-233/Th fuels at a lower power density or to develop alternative refueling schemes that will lower the time-average specific power, thereby increasing burnup.(author)

Power level effects on thorium-based fuels in pressure-tube heavy water reactors

International Nuclear Information System (INIS)

Bromley, B.P.; Edwards, G.W.R.; Sambavalingam, P.

2016-01-01

Lattice and core physics modeling and calculations have been performed to quantify the impact of power/flux levels on the reactivity and achievable burnup for 35-element fuel bundles made with Pu/Th or U-233/Th. The fissile content in these bundles has been adjusted to produce on the order of 20 MWd/kg burnup in homogeneous cores in a 700 MWe-class pressure-tube heavy water reactor, operating on a once-through thorium cycle. Results demonstrate that the impact of the power/flux level is modest for Pu/Th fuels but significant for U-233/Th fuels. In particular, high power/flux reduces the breeding and burnup potential of U-233/Th fuels. Thus, there may be an incentive to operate reactors with U-233/Th fuels at a lower power density or to develop alternative refueling schemes that will lower the time-average specific power, thereby increasing burnup.(author)

12 CFR Appendix A to Part 233 - Model Notice

Science.gov (United States)

2010-01-01

... FUNDING OF UNLAWFUL INTERNET GAMBLING (REGULATION GG) Part 233, App. A Appendix A to Part 233—Model Notice... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Model Notice A Appendix A to Part 233 Banks and... that your institution processed payments through our facilities for Internet gambling transactions...

40 CFR 86.233-94-86.234-94 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 18 2010-07-01 2010-07-01 false [Reserved] 86.233-94-86.234-94 Section 86.233-94-86.234-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures §§ 86.233-94—86.234-94 [Reserved] ...

27 CFR 24.233 - Addition of spirits to wine.

Science.gov (United States)

2010-04-01

... wine. 24.233 Section 24.233 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.233 Addition of spirits to wine. (a) Prior to the addition of spirits. Wine will be placed in tanks approved for the addition of spirits. The...

Molten-salt reactor strategies viewed from fuel conservation effect, (1)

International Nuclear Information System (INIS)

Furuhashi, Akira

1976-01-01

Saving of material requirements in the long-term fuel cycle is studied by introducing molten-salt reactors with good neutron economy into a projection of nuclear generating capacity in Japan. In this first report an examination is made on the effects brought by the introduction of molten-salt converter reactors starting with Pu which are followed by 233 U breeders of the same type. It is shown that the sharing of some Pu in the light water- and fast breeder-reactor system with molten-salt reactors provides a more rapid transition to the self-supporting, breeding cycle than the simple fast breeding system, thus leading to an appreciable fuel conservation. Considerations are presented on the strategic repartition of generating capacity among reactor types and it is shown that all of the converted 233 U should be promptly invested to molten-salt breeders to quickly establish the dual breeding system, instead of recycling to converters themselves. (auth.)

40 CFR 233.12 - Attorney General's statement.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Attorney General's statement. 233.12... STATE PROGRAM REGULATIONS Program Approval § 233.12 Attorney General's statement. (a) Any State that seeks to administer a program under this part shall submit a statement from the State Attorney General...

Fusion-breeder program

International Nuclear Information System (INIS)

Moir, R.W.

1982-01-01

The various approaches to a combined fusion-fission reactor for the purpose of breeding 239 Pu and 233 U are described. Design aspects and cost estimates for fuel production and electricity generation are discussed

14 CFR 61.73 - Military pilots or former military pilots: Special rules.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Military pilots or former military pilots... Ratings and Pilot Authorizations § 61.73 Military pilots or former military pilots: Special rules. (a... a disciplinary action involving aircraft operations, a U.S. military pilot or former military pilot...

ISO 50001 for Commercial Buildings: Lessons Learned From U.S. DOE Pilot Project: Preprint

Energy Technology Data Exchange (ETDEWEB)

Deru, M.; Field, K.; Punjabi, S.

2014-08-01

In the U.S., the ISO 50001 Standard, which establishes energy management systems (EnMSs) and processes, has shown uptake primarily in the industrial sector. The U.S. Department of Energy (DOE) undertook a pilot program to explore ISO 50001 implementation in commercial buildings. Eight organizations participated as pilots, with technical assistance provided by DOE, the National Renewable Energy Laboratory (NREL), the Lawrence Berkeley National Laboratory (LBNL), and the Georgia Institute of Technology (Georgia Tech). This paper shares important lessons learned from the pilot. Staff time was the most critical resource required to establish effective EnMSs in commercial buildings. The pilot also revealed that technical support and template/example materials were essential inputs. Crucial activities included evaluating performance, identifying goals, making connections, communicating operational controls, and tracking/reviewing progress. Benefits realized included enhanced intra-organizational connections, greater energy awareness, increased process efficiencies, and improved ability to make business cases. Incremental benefits for ISO 50001 certification were greater accountability, assurance of best practices, public relations opportunities, and potential to unlock verified savings credits or incentive money. Incremental certification costs included more staff/consultant time, money for certification, and a tendency to limit EnMS scope in order to ensure favorable audit results. Five best practices were identified - utilizing expert technical assistance, training, and other resources; focusing on implementation over documentation; keeping top management involved; considering organizational structure when selecting EnMS scope; and matching the implementation level to an EnMS's scope and scale. The last two practices are particularly relevant to the commercial buildings sector.

Does Flooring Substrate Impact Kennel and Dog Cleanliness in Commercial Breeding Facilities?

Directory of Open Access Journals (Sweden)

Judith Stella

2018-04-01

Full Text Available Evaluation of kennel flooring surfaces is needed to understand their impacts on dog health and well-being. This pilot study aimed to characterize aspects of physical health, kennel cleanliness, and dog body cleanliness on flooring types common in US breeding kennels. Subjects were 118 adult dogs housed on diamond-coated expanded metal (DCEM, polypropylene (POLY, or concrete (CON flooring at five commercial breeding facilities in Indiana, U.S. Body condition, paw, elbow, and hock health scores were recorded. Each indoor kennel and dog was visually assessed for cleanliness. Kennels were swabbed immediately after cleaning with electrostatic dry cloths and cultured for Escherichia coli. Descriptive statistics were used for analysis. Mean body condition score (BCS, kennel and dog cleanliness scores were all near ideal (3, 1.15, and 1.04, respectively. Thirty-one percent or fewer kennels at each facility were culture-positive for E. coli after cleaning. No serious paw, elbow, or hock problems were identified. Overall, the findings indicate that with appropriate management and regular access to additional surfaces, dog foot health, cleanliness, and kennel cleanliness can be maintained on the flooring types investigated.

48 CFR 852.233-70 - Protest content/alternative dispute resolution.

Science.gov (United States)

2010-10-01

.../alternative dispute resolution. 852.233-70 Section 852.233-70 Federal Acquisition Regulations System... Provisions and Clauses § 852.233-70 Protest content/alternative dispute resolution. As prescribed in 833.106, insert the following provision: Protest Content/Alternative Dispute Resolution (JAN 2008) (a) Any protest...

Does Flooring Substrate Impact Kennel and Dog Cleanliness in Commercial Breeding Facilities?

Science.gov (United States)

Stella, Judith; Hurt, Moriah; Bauer, Amy; Croney, Candace

2018-01-01

Simple Summary It is important to understand how the flooring substrate used in dog housing impacts dog health and well-being. Aspects to consider include paw, elbow, and hock health, the cleanliness of the dog, and the ability of the floors to be cleaned easily and thoroughly. This pilot study assessed the health and cleanliness of 118 dogs housed on three different types of flooring commonly found in commercial breeding kennels. No serious paw, elbow, or hock problems were identified. Thirty-one percent or fewer kennels at each facility were found to have fecal contamination after routine cleaning and the majority of dogs were clean. These findings indicate that a well-managed kennel can maintain clean, healthy dogs on different types of flooring substrates. Abstract Evaluation of kennel flooring surfaces is needed to understand their impacts on dog health and well-being. This pilot study aimed to characterize aspects of physical health, kennel cleanliness, and dog body cleanliness on flooring types common in US breeding kennels. Subjects were 118 adult dogs housed on diamond-coated expanded metal (DCEM), polypropylene (POLY), or concrete (CON) flooring at five commercial breeding facilities in Indiana, U.S. Body condition, paw, elbow, and hock health scores were recorded. Each indoor kennel and dog was visually assessed for cleanliness. Kennels were swabbed immediately after cleaning with electrostatic dry cloths and cultured for Escherichia coli. Descriptive statistics were used for analysis. Mean body condition score (BCS), kennel and dog cleanliness scores were all near ideal (3, 1.15, and 1.04, respectively). Thirty-one percent or fewer kennels at each facility were culture-positive for E. coli after cleaning. No serious paw, elbow, or hock problems were identified. Overall, the findings indicate that with appropriate management and regular access to additional surfaces, dog foot health, cleanliness, and kennel cleanliness can be maintained on the flooring

20 CFR 410.233 - Cancellation of a request for withdrawal.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Cancellation of a request for withdrawal. 410.233 Section 410.233 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND... Entitlement; Filing of Claims and Evidence § 410.233 Cancellation of a request for withdrawal. Before or after...

76 FR 60960 - Gulf Opportunity Pilot Loan Program (GO Loan Pilot)

Science.gov (United States)

2011-09-30

... SMALL BUSINESS ADMINISTRATION Gulf Opportunity Pilot Loan Program (GO Loan Pilot) AGENCY: U.S.... SUMMARY: This notice announces the extension of SBA's GO Loan Pilot, with modifications, until December 31... processing available through the GO Loan Pilot to small businesses in the eligible parishes/counties through...

Feasibility study and economic analysis on thorium utilization in heavy water reactors

International Nuclear Information System (INIS)

1978-07-01

Even though natural uranium is a more easily usable fuel in heavy water reactors, thorium fuel cycles have also been considered owing to certain attractive features of the thorium fuel cycle in heavy water reactors. The relatively higher fission neutron yield per thermal neutron absorption in 233 U combined with the very low neutron absorption cross section of heavy water make it possible to achieve breeding in a heavy water reactor operating on Th- 233 U fuel cycle. Even if the breeding ratio is very low, once a self-sustaining cycle is achieved, thereafter dependence on uranium can be completely eliminated. Thus, with a self-sustaining Th- 233 U fuel cycle in heavy water reactors, a given quantity of natural uranium will be capable of supporting a much larger installed generating capacity to significantly longer period of time. However, since thorium does not contain any fissile isotope, fissile material has to be added at the beginning. Concentrated fissile material is considerably more expensive than the 235 U contained in natural uranium. This makes the fuel cycle cost higher with thorium fuel cycle, at least during the initial stages. The situation is made worse by the fact that, because of its higher thermal neutron absorption cross section, thorium requires a higher concentration of fissile material than 238 U. Nevertheless, because of the superior nuclear characteristics of 233 U, once uranium becomes more expensive, thorium fuel cycle in heavy water reactors may become economically acceptable. Furthermore, the energy that can be made available from a given quantity of uranium is considerably increased with a self-sustaining thorium fuel cycle

Final report for the Light Water Breeder Reactor proof-of-breeding analytical support project

International Nuclear Information System (INIS)

Graczyk, D.G.; Hoh, J.C.; Martino, F.J.; Nelson, R.E.; Osudar, J.; Levitz, N.M.

1987-05-01

The technology of breeding 233 U from 232 Th in a light water reactor is being developed and evaluated by the Westinghouse Bettis Atomic Power Laboratory (BAPL) through operation and examination of the Shippingport Light Water Breeder Reactor (LWBR). Bettis is determining the end-of-life (EOL) inventory of fissile uranium in the LWBR core by nondestructive assay of a statistical sample comprising approximately 500 EOL fuel rods. This determination is being made with an irradiated-fuel assay gauge based on neutron interrogation and detection of delayed neutrons from each rod. The EOL fissile inventory will be compared with the beginning-of-life fissile loading of the LWBR to determine the extent of breeding. In support of the BAPL proof-of-breeding (POB) effort, Argonne National Laboratory (ANL) carried out destructive physical, chemical, and radiometric analyses on 17 EOL LWBR fuel rods that were previously assayed with the nondestructive gauge. The ANL work included measurements on the intact rods; shearing of the rods into pre-designated contiguous segments; separate dissolution of each of the more than 150 segments; and analysis of the dissolver solutions to determine each segment's uranium content, uranium isotopic composition, and loading of selected fission products. This report describes the facilities in which this work was carried out, details operations involved in processing each rod, and presents a comprehensive discussion of uncertainties associated with each result of the ANL measurements. Most operations were carried out remotely in shielded cells. Automated equipment and procedures, controlled by a computer system, provided error-free data acquisition and processing, as well as full replication of operations with each rod. Despite difficulties that arose during processing of a few rod segments, the ANL destructive-assay results satisfied the demanding needs of the parent LWBR-POB program

Final report for the Light Water Breeder Reactor proof-of-breeding analytical support project

Energy Technology Data Exchange (ETDEWEB)

Graczyk, D.G.; Hoh, J.C.; Martino, F.J.; Nelson, R.E.; Osudar, J.; Levitz, N.M.

1987-05-01

The technology of breeding /sup 233/U from /sup 232/Th in a light water reactor is being developed and evaluated by the Westinghouse Bettis Atomic Power Laboratory (BAPL) through operation and examination of the Shippingport Light Water Breeder Reactor (LWBR). Bettis is determining the end-of-life (EOL) inventory of fissile uranium in the LWBR core by nondestructive assay of a statistical sample comprising approximately 500 EOL fuel rods. This determination is being made with an irradiated-fuel assay gauge based on neutron interrogation and detection of delayed neutrons from each rod. The EOL fissile inventory will be compared with the beginning-of-life fissile loading of the LWBR to determine the extent of breeding. In support of the BAPL proof-of-breeding (POB) effort, Argonne National Laboratory (ANL) carried out destructive physical, chemical, and radiometric analyses on 17 EOL LWBR fuel rods that were previously assayed with the nondestructive gauge. The ANL work included measurements on the intact rods; shearing of the rods into pre-designated contiguous segments; separate dissolution of each of the more than 150 segments; and analysis of the dissolver solutions to determine each segment's uranium content, uranium isotopic composition, and loading of selected fission products. This report describes the facilities in which this work was carried out, details operations involved in processing each rod, and presents a comprehensive discussion of uncertainties associated with each result of the ANL measurements. Most operations were carried out remotely in shielded cells. Automated equipment and procedures, controlled by a computer system, provided error-free data acquisition and processing, as well as full replication of operations with each rod. Despite difficulties that arose during processing of a few rod segments, the ANL destructive-assay results satisfied the demanding needs of the parent LWBR-POB program.

Calibration of 232U solution; Calibracion de una disolucion de 232U

Energy Technology Data Exchange (ETDEWEB)

Galan Valera, M P; Acena Berrenechea, M L

1988-07-01

A method for as certain the activity by alpha spectroscopy with semiconductor detectors, of a solution of 232U is presented. It consists of the comparison with a 233U solution activity previously measured in a gridded ionization chamber of 2{pi} geometry. The total measurement uncertainty is about + - 0,02. (Author) 9 refs.

New calculation for the neutron-induced fission cross section of 233Pa between 1.0 and 3.0 MeV

International Nuclear Information System (INIS)

Mesa, J.; Deppman, A.; Likhachev, V.P.; Arruda-Neto, J.D.T.; Manso, M.V.; Garcia, C.E.; Rodriguez, O.; Guzman, F.; Garcia, F.

2003-01-01

The 233 Pa(n,f) cross section, a key ingredient for fast reactors and accelerators driven systems, was measured recently with relatively good accuracy [F. Tovesson et al., Phys. Rev. Lett. 88, 062502 (2002)]. The results are at strong variance with accepted evaluations and an existing indirect experiment. This circumstance led us to perform a quite detailed and complete evaluation of the 233 Pa(n,f) cross section between 1.0 and 3.0 MeV, where use of our newly developed routines for the parametrization of the nuclear surface and the calculation of deformation parameters and level densities (including low-energy discrete levels) were made. The results show good quantitative and excellent qualitative agreement with the experimental direct data obtained by Tovesson et al. [F. Tovesson et al., Phys. Rev. Lett. 88, 062502 (2002)]. Additionally, our methodology opens new possibilities for the analysis of subthreshold fission and above threshold second-chance fission for both 233 Pa and its decay product 233 U, as well as other strategically important fissionable nuclides

17 CFR 201.233 - Depositions upon oral examination.

Science.gov (United States)

2010-04-01

... examination. 201.233 Section 201.233 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... upon oral examination. (a) Procedure. Any party desiring to take the testimony of a witness by.... Examination and cross-examination of deponents may proceed as permitted at a hearing. The witness being...

75 FR 53007 - Gulf Opportunity Pilot Loan Program (GO Loan Pilot)

Science.gov (United States)

2010-08-30

... SMALL BUSINESS ADMINISTRATION Gulf Opportunity Pilot Loan Program (GO Loan Pilot) AGENCY: U.S...'s GO Loan Pilot until September 30, 2011. Due to the scope and magnitude of the devastation to... streamlined and centralized loan processing available through the GO Loan Pilot to small businesses in the...

Investigation of neutronic behavior in a CANDU reactor with different (Am, Th, {sup 235}U)O{sub 2} fuel matrixes

Energy Technology Data Exchange (ETDEWEB)

Gholamzadeh, Z. [Talca Univ. (Chile). Dept. of Physics; Feghhi, S.A.H. [Shahid Beheshti Univ., Tehran (Iran, Islamic Republic of). Dept. of Radiation Application

2014-11-15

Recently thorium-based fuel matrixes are taken into consideration for nuclear waste incineration because of thorium proliferation resistance feature moreover its breeding or convertor ability in both thermal and fast reactors. In this work, neutronic influences of adding Am to (Th-{sup 235}U)O{sub 2} on effective delayed neutron fraction, reactivity coefficients and burn up of a fed CANDU core has been studied using MCNPX 2.6.0 computational code. Different atom fractions of Am have been introduced in the fuel matrix to evaluate its effects on neutronic parameters of the modeled core. The computational data show that adding 2% atom fraction of Am to thorium-based fuel matrix won't noticeably change reactivity coefficients in comparison with the fuel matrix containing 1% atom fraction of Am. The use of 2% atom fraction of Am resulted in a higher delayed neutron fraction. According to the obtained data, 32.85 GWd burn up of the higher Americium-containing fuel matrix resulted in 55.2%, 26.5%, 41.9% and 2.14% depletion of {sup 241}Am, {sup 243}Am, {sup 235}U and {sup 232}Th respectively. 132.8 kg of {sup 233}U fissile element is produced after the burn up time and the nuclear core multiplication factor increases in rate of 2390 pcm. The less americium-containing fuel matrix resulted in higher depletion of {sup 241/243}Am, {sup 235}U and {sup 232}Th while the nuclear core effective multiplication factor increases in rate of 5630 pcm after the burn up time with 9.8 kg additional {sup 233}U production.

33 CFR 136.233 - Proof.

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2010-07-01

... SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.233 Proof. In addition to the... must be established. (d) Whether alternative employment or business was available and undertaken and...

45 CFR 233.51 - Eligibility of sponsored aliens.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 2 2010-10-01 2010-10-01 false Eligibility of sponsored aliens. 233.51 Section... CONDITIONS OF ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.51 Eligibility of sponsored aliens... affidavit(s) of support or similar agreement on behalf of an alien (who is not the child of the sponsor or...

Neutron-induced fission cross-section of 233U, 241Am and 243Am in the energy range 0.5 MeV ≤ En ≤ 20 MeV

International Nuclear Information System (INIS)

Belloni, F.; Milazzo, P.M.; Calviani, M.

2011-01-01

Neutron-induced fission cross-sections of 233 U, 241 Am and 243 Am relative to 235 U have been measured in a wide energy range at the neutron time of flight facility n-TOF in Geneva to address the present discrepancies in evaluated and experimental databases for reactions and isotopes relevant for transmutation and new generation fast reactors. A dedicated fast ionization chamber was used. Each isotope was mounted in a different cell of the modular detector. The measurements took advantage of the characteristics of the n-TOF installation. Its intrinsically low background, coupled to its high instantaneous neutron flux, results in high accuracy data. Its wide energy neutron spectrum helps to reduce systematic uncertainties due to energy-domain matching problems while the 185 m flight path and a 6 ns pulse width assure an excellent energy resolution. This paper presents results obtained between 500 keV and 20 MeV neutron energy. (authors)

Potential for the near-term use of the thorium cycle in a sustainable way

International Nuclear Information System (INIS)

Wider, H.; Tucek, K.; Carlsson, J.

2007-01-01

Nuclear sustainability is generally believed to be only reachable through the building of many fast breeder reactors. This paper shows that there is another possibility by using existing reactors that are either thermal breeders or have at least a high conversion ratio and considerably smaller critical masses than fast systems. Earlier it was believed that thermal molten salt breeders could eventually use the thorium / 233U cycle, which doesn't generate minor actinides and is therefore a cleaner fuel cycle. In the meantime, it has become rather clear that CANDU reactors that use heavy water cooling can also be self-breeders. The CANDU reactors could generate themselves 233U in thorium targets and could become selfsustaining after 12 years. However, additional 233U could also be generated in LWRs and fast reactors. It is shown that this generation of 233U will allow a faster large-term nuclear expansion than fast reactors alone. There could actually be a synergy between thermal and fast breeders if the latter are run with Pu/Minor Actinides/Th fuel, which burns the minor actinides and generates sizeable amounts of 233U. The main problem is still the necessary reprocessing on which India is working and intends to have in 10 years a large scale reprocessing facility available. However, there is at least an existing method for removing the 233U by the fluoride volatility method and to further use it in CANDUs. For the preparation of the use of 233U, we should attempt to run thorium subassemblies in CANDUs, LWRs, and fast reactors. Besides breeding 233U or at least having a high conversion ratio, CANDUs have the further advantage that they don't need a pressure vessel and therefore could be built in large numbers faster than LWRs. (author)

48 CFR 1852.233-70 - Protests to NASA.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Protests to NASA. 1852.233... 1852.233-70 Protests to NASA. As prescribed in 1833.106-70, insert the following provision: Protests to NASA (OCT 2002) Potential bidders or offerors may submit a protest under 48 CFR part 33 (FAR part 33...

Reflector drums as control mechanism for craft thermionic reactors with constant emitter heating containing U-233 as fuel and beryllium as moderator

International Nuclear Information System (INIS)

Sahin, S.; Selvi, S.

1980-01-01

The suitability of borated reflector drums has been investigated and shown as a control mechanism for space craft thermionic reactors with constant emitter heating using U-233 as fuel and beryllium to be moderator, mainly due to their extremce compactness and their very soft neutron sepctrum. The achievable change in ksub(eff) allows long-term control operation with success. The use of reflector drums keeps the cone diameter and the mass of the radiation shield on minimum. The distortion of the emitter heating field remains under acceptable tolerances, mainly due to the enhanced neutron production at the outer core region and the remaining reflector part between the boron layer and the core. All neutron physics calculations have been carried out using the multigroup Ssub(N) methods. Three data groups for r-theta-calculations in S 4 -P 1 approximation (16 space angles) have been evaluated from a 123-energy-groups data library using transport theoretical methods. (orig.) [de

Separation of the rare earths by high pressure liquid chromatography and the fission yield on sup(148m)Pm and sup(148g)Pm using thermal neutron induced fission of 233U and 239Pu

International Nuclear Information System (INIS)

Zwicky, H.U.

1979-03-01

This report is in two parts: in the first part, the method of high pressure liquid chromatography is described with particular reference to rare earth nuclei produced in nuclear reactions; in the second part, the results of a study of the fission yield of sup(148m)Pm and sup(148g)Pm from the thermal fission of 233 U and 239 Pu are presented. (G.T.H.)

Short communication: study of immune parameters in three Greek dairy sheep breeds during the periparturient period.

Science.gov (United States)

Theodorou, G; Fragou, S; Chronopoulou, R; Kominakis, A; Rogdakis, E; Politis, I

2007-12-01

The objective of the present study was to evaluate whether immunosuppression occurs in 3 different Greek dairy sheep breeds during the periparturient period. A total of 33 ewes from 3 breeds [i.e., the low-producing Boutsiko breed (n = 11), which is highly adaptable to harsh environments; the high-producing but environmentally fragile Chios breed (n = 11); and an intermediate synthetic breed (50% Boutsiko, 25% Arta, and 25% Chios, n = 11)] were used. Blood samples were collected at 18 and 2 d before parturition and at 15 d after parturition. Total cell-associated and membrane-bound urokinase plasminogen activator (U-PA) activity, free U-PA binding sites on cellular membranes, and superoxide anion (SA) production by activated phagocytes were determined. Results indicated that all immune parameters measured remained constant during the periparturient period for the Boutsiko breed. In contrast, there were reductions in total cell-associated and membrane-bound U-PA activity by both monocytes-macrophages and neutrophils and in SA production by monocytes-macrophages at d 2 before parturition for the Chios breed. In the synthetic breed, there were reductions in total cell-associated and membrane-bound U-PA activity by monocytes-macrophages and in SA production by both monocytes-macrophages and neutrophils at d 15 after parturition. Thus, mild immunosuppression during the periparturient period was observed in the 2 breeds with the highest milk production.

Breeding gains of sodium-cooled oxide-fueled fast reactors

International Nuclear Information System (INIS)

Mougniot, J.C.; Barre, J.Y.; Clauzon, P.; Ciacometti, C.; Neviere, G.; Ravier, J.; Sichard, B.

Calculated values are presented for the breeding gains of French fast reactors, and the experimental uncertainties are discussed. The effect of various choices of planning on the breeding gains is next analyzed within the framework of classical concepts. In the final part, a new concept involving ''heterogeneous cores'' with a single enrichment zone is presented. This concept permits a significant improvement in the breeding gain and doubling time of fast reactors. (U.S.)

233-S Plutonium Concentration Facility data quality objectives

International Nuclear Information System (INIS)

Encke, D.B.

1996-08-01

This document is a summary of the decision-making associated with the Data Quality Objective process that pertains to the characterization activities in the 233-S Plutonium Concentration Facility at the Hanford Site in Richland, Washington. The 233-S Plutonium Concentration Facility is located adjacent to, and north of, the REDOX Plant. The facility was used to concentrate the plutonium nitrate product solution from the REDOX facility. The 233-S Pipe Gallery, Control Room, SWP Change Room, Toilet, Equipment Room and the Electrical Cubicle are currently scheduled for decontamination and cleanout to support future demolition (D and D). Identification of the radiological contamination and presence of hazardous materials is needed to allow for disposal of the D and D debris

Separation of silicon carbide-coated fertile and fissile particles by gas classification

International Nuclear Information System (INIS)

Vaughen, V.C.A.

1976-07-01

The separation of 235 U and 233 U in the reprocessing of HTGR fuels is a key feature of the feed-breed fuel cycle concept. This is attained in the Fort St. Vrain (FSV) reactor by coating the fissile (Th- 235 U) particles and the fertile (Th- 233 U) particles separately with silicon carbide (SiC) layers to contain the fission products and to protect the kernels from burning in the head-end reprocessing steps. Pneumatic (gas) classification based on size and density differences is the reference process for separating the SiC-coated particles into fissile and fertile streams for subsequent handling. Terminal velocities have been calculated for the +- 2 sigma ranges of particle sizes and densities for ''Fissile B''--''Fertile A'' particles used in the FSV reactor. Because of overlapping particle fractions, a continuous pneumatic separator appears infeasible; however, a batch separation process can be envisioned. Changing the gas from air to CO 2 and/or the temperature to 300 0 C results in less than 10 percent change in calculated terminal velocities. Recently reported work in gas classification is discussed in light of the theoretical calculations. The pneumatic separation of fissile and fertile particles needs more study, specifically with regard to (1) measuring the recoveries and separation efficiencies of actual fissile and fertile fractions in the tests of the pneumatic classifiers; and (2) improving the contactor design or flowsheet to avoid apparent flow separation or flooding problems at the feed point when using the feed rates required for the pilot plant

Thorium Molten Salt Nuclear Energy Synergetic System (THORIMS-NES)

International Nuclear Information System (INIS)

Yoshioka, Ritsuo; Mitachi, Koshi

2013-01-01

The authors have been promoting nuclear energy technology based on thorium molten salt as Thorium Molten Salt Nuclear Energy Synergetic System (THORIMS-NES). This system is a combination of fission power reactor of Molten Salt Reactor (MSR), and Accelerator Molten Salt Breeder (AMSB) for production of fissile 233 U with connecting chemical processing facility. In this paper, concept of THORIMS-NES, advantages of thorium and molten salt recent MSR design results such as FUJI-U3 using 233 U fuel, FUJI-Pu, large sized super-FUJI, pilot plant miniFUJI, AMSB, and chemical processing facility are described. (author)

On-site transportation and handling of uranium-233 special nuclear material: Preliminary hazards and accident analysis. Final

International Nuclear Information System (INIS)

Solack, T.; West, D.; Ullman, D.; Coppock, G.; Cox, C.

1995-01-01

U-233 Special Nuclear Material (SNM) currently stored at the T-Building Storage Areas A and B must be transported to the SW/R Tritium Complex for repackaging. This SNM is in the form of oxide powder contained in glass jars which in turn are contained in heat sealed double polyethylene bags. These doubled-bagged glass jars have been primarily stored in structural steel casks and birdcages for approximately 20 years. The three casks, eight birdcages, and one pail/pressure vessel will be loaded onto a transport truck and moved over an eight day period. The Preliminary Hazards and Accident Analysis for the on-site transportation and handling of Uranium-233 Special Nuclear Material, documented herein, was performed in accordance with the format and content guidance of DOE-STD-3009-94, Preparation Guide for US Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports, dated July 1994, specifically Chapter Three, Hazard and Accident Analysis. The Preliminary Hazards Analysis involved detailed walkdowns of all areas of the U-233 SNM movement route, including the T-Building Storage Area A and B, T-Building truck tunnel, and the roadway route. Extensive discussions were held with operations personnel from the Nuclear Material Control Group, Nuclear Materials Accountability Group, EG and G Mound Security and the Material Handling Systems Transportation Group. Existing documentation related to the on-site transportation of hazardous materials, T-Building and SW/R Tritium Complex SARs, and emergency preparedness/response documentation were also reviewed and analyzed to identify and develop the complete spectrum of energy source hazards

49 CFR 233.5 - Accidents resulting from signal failure.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Accidents resulting from signal failure. 233.5... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION SIGNAL SYSTEMS REPORTING REQUIREMENTS § 233.5 Accidents resulting... by toll free telephone, number 800-424-0201, whenever it learns of the occurrence of an accident...

Retaining U.S. Air Force Pilots When the Civilian Demand for Pilots Is Growing

Science.gov (United States)

2016-01-01

compensation, so a 1-percent increase in basic pay is like a 0.6-percent increase in total pay, other things being equal . If so, the retention change...at other major airlines.3 The collective bargaining agreement called for American/US Airways pilots to reach pay parity with Delta and United pilots...non-veterans in non- pilot occupations after controlling for age, education, and gender . But the results show that pilots who are veterans earn 10 to

Calibration of 232U solution

International Nuclear Information System (INIS)

Galan Valera, M. P.; Acena Berrenechea, M. L.

1988-01-01

A method for as certain the activity by alpha spectroscopy with semiconductor detectors, of a solution of 232U is presented. It consists of the comparison with a 233U solution activity previously measured in a gridded ionization chamber of 2π geometry. The total measurement uncertainty is about + - 0,02. (Author) 9 refs

Study on Utilization of Super Grade Plutonium in Molten Salt Reactor FUJI-U3 using CITATION Code

Science.gov (United States)

Wulandari, Cici; Waris, Abdul; Pramuditya, Syeilendra; Asril, Pramutadi AM; Novitrian

2017-07-01

FUJI-U3 type of Molten Salt Reactor (MSR) has a unique design since it consists of three core regions in order to avoid the replacement of graphite as moderator. MSR uses floride as a nuclear fuel salt with the most popular chemical composition is LiF-BeF2-ThF4-233UF4. ThF4 and 233UF4 are the fertile and fissile materials, respectively. On the other hand, LiF and BeF2 working as both fuel and heat transfer medium. In this study, the super grade plutonium will be utilized as substitution of 233U since plutonium is easier to be obtained compared to 233U as main fuel. Neutronics calculation was performed by using PIJ and CITATION modules of SRAC 2002 code with JENDL 3.2 as nuclear data library.

Special topics reports for the reference tandem mirror fusion breeder. Volume 5. Neutronic issues and optimization

Energy Technology Data Exchange (ETDEWEB)

Lee, J.D.; Bandini, B.R.

1985-03-29

More rigorous nuclear analysis, including the treatment of resonance self-shielding effects coupled with an optimization procedure, has resulted in improved performance of the Be/Li/Th blanket. Net U-233 breeding ratio has increased 36% (to 0.84) while at a U/Th ratio of 0.25 a/o energy multiplication has increased 12% (to 2.1) compared with earlier results.

Special topics reports for the reference tandem mirror fusion breeder. Volume 5. Neutronic issues and optimization

International Nuclear Information System (INIS)

Lee, J.D.; Bandini, B.R.

1985-01-01

More rigorous nuclear analysis, including the treatment of resonance self-shielding effects coupled with an optimization procedure, has resulted in improved performance of the Be/Li/Th blanket. Net U-233 breeding ratio has increased 36% (to 0.84) while at a U/Th ratio of 0.25 a/o energy multiplication has increased 12% (to 2.1) compared with earlier results

Accelerator-breeder, an application of high-energy accelerators to solving our energy problems

International Nuclear Information System (INIS)

Grand, P.; Batchelor, K.; Powell, J.R.; Steinberg, M.

1977-01-01

The rising costs of 235 U and other fossil fuels, and the schedule for implementing the breeder reactor have renewed interest in the utilization of accelerators for breeding 233 U or 239 Pu. A discussion is given of some of the basic accelerator parameters and choices to be made in order to meet the technical and economic requirements of such a facility

27 CFR 46.233 - Payment of floor stocks tax.

Science.gov (United States)

2010-04-01

... tax. 46.233 Section 46.233 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE...) Electronic funds transfer. If the dealer pays any other excise taxes collected by TTB by electronic funds transfer, then the dealer must also send the payment for the floor stocks tax by an electronic funds...

75 FR 68018 - Airport Privatization Pilot Program

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2010-11-04

... Privatization Pilot Program AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Receipt and... preliminary application for participation in the airport privatization pilot program received under 49 U.S.C... final application to the FAA for exemption under the pilot program. 49 U.S.C. Section 47134 establishes...

75 FR 39091 - Airport Privatization Pilot Program

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2010-07-07

... Privatization Pilot Program AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Receipt and... application for participation in the airport privatization pilot program received under 49 U.S.C. 47134. The... application to the FAA for exemption under the pilot program. 49 U.S.C. 47134 establishes an airport...

28 CFR 23.3 - Applicability.

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2010-07-01

... Administration DEPARTMENT OF JUSTICE CRIMINAL INTELLIGENCE SYSTEMS OPERATING POLICIES § 23.3 Applicability. (a) These policy standards are applicable to all criminal intelligence systems operating through support...-647). (b) As used in these policies: (1) Criminal Intelligence System or Intelligence System means the...

45 CFR 233.32 - Payment and budget months (AFDC).

Science.gov (United States)

2010-10-01

... 45 Public Welfare 2 2010-10-01 2010-10-01 false Payment and budget months (AFDC). 233.32 Section... CONDITIONS OF ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.32 Payment and budget months (AFDC). A State... period used to determine that payment (budget month) and whether it adopts (a) a one-month or two-month...

Study of DD versus DT fusion fuel cycles for different fusion-fission hybrid energy systems

International Nuclear Information System (INIS)

Gohar, Y.; Baker, C.C.

1981-01-01

A study was performed to investigate the characteristics of an energy system to produce fissile fuel for fission reactors. DD and DT fusion reactors were examined in this study with either a thorium or uranium blanket for each fusion reactor. Various fuel cycles were examined for light-water reactors including the denatured fuel cycles (which may offer proliferation resistance compared to other fuel cycles); these fuel cycles include a uranium fuel cycle with 239 Pu makeup, a thorium fuel cycle with 239 Pu makeup, a denatured uranium fuel cycle with 233 U makeup, and a denatured thorium fuel cycle with 233 U makeup. Four different blankets were considered for this study. The first two blankets have a tritium breeding capability for DT reactors. Lithium oxide (Li 2 O) was used for tritium breeding due to its high lithium density and high temperature capability; however, the use of Li 2 O may result in higher tritium inventories compared to other solid breeders

Steroidal glycoalkaloids in Solanum species : consequences for potato breeding and food safety

NARCIS (Netherlands)

Gelder, van W.M.J.

1989-01-01

Tuberiferous and nontuberiferous wild <u>Solanum> species are increasingly being used in potato breeding as a source of genes for disease and pest resistances and for other valuable characteristics. A disadvantage of <u>Solanum> species, from a consumers point

Feasibility study of a fission-suppressed tokamak fusion breeder

International Nuclear Information System (INIS)

Moir, R.W.; Lee, J.D.; Neef, W.S.

1984-12-01

The preliminary conceptual design of a tokamak fissile fuel producer is described. The blanket technology is based on the fission suppressed breeding concept where neutron multiplication occurs in a bed of 2 cm diameter beryllium pebbles which are cooled by helium at 50 atmospheres pressure. Uranium-233 is bred in thorium metal fuel elements which are in the form of snap rings attached to each beryllium pebble. Tritium is bred in lithium bearing material contained in tubes immersed in the pebble bed and is recovered by a purge flow of helium. The neutron wall load is 3 MW/m 2 and the blanket material is ferritic steel. The net fissile breeding ratio is 0.54 +- 30% per fusion reaction. This results in the production of 4900 kg of 233 U per year from 3000 MW of fusion power. This quantity of fuel will provide makeup fuel for about 12 LWRs of equal thermal power or about 18 1 GW/sub e/ LWRs. The calculated cost of the produced uranium-233 is between $23/g and $53/g or equivalent to $10/kg to $90/kg of U 3 O 8 depending on government financing or utility financing assumptions. Additional topics discussed in the report include the tokamak operating mode (both steady state and long pulse considered), the design and breeding implications of using a poloidal divertor for impurity control, reactor safety, the choice of a tritium breeder, and fuel management

Concept of a demonstrational hybrid reactor—a tokamak with molten-salt blanket for {sup 233}U fuel production: 1. Concept of a stationary Tokamak as a neutron source

Energy Technology Data Exchange (ETDEWEB)

Azizov, E. A.; Gladush, G. G., E-mail: gladush@triniti.ru; Dokuka, V. N.; Khayrutdinov, R. R. [State Research Center of the Russian Federation, Troitsk Institute for Innovation and Fusion Research (Russian Federation)

2015-12-15

On the basis of current understanding of physical processes in tokamaks and taking into account engineering constraints, it is shown that a low-cost facility of a moderate size can be designed within the adopted concept. This facility makes it possible to achieve the power density of neutron flux which is of interest, in particular, for solving the problem of {sup 233}U fuel production from thorium. By using a molten-salt blanket, the important task of ensuring the safe operation of such a reactor in the case of possible coolant loss is accomplished. Moreover, in a hybrid reactor with the blanket based on liquid salts, the problem of periodic refueling that is difficult to perform in solid blankets can be solved.

47 CFR 90.233 - Base/mobile non-voice operations.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Base/mobile non-voice operations. 90.233... SERVICES PRIVATE LAND MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.233 Base/mobile non-voice operations. The use of A1D, A2D, F1D, F2D, G1D, or G2D emission may be authorized to base...

5 CFR 532.233 - Preparation for full-scale wage surveys.

Science.gov (United States)

2010-01-01

... presence on the job, and the prudent management of available financial and human resources. Employing.... 532.233 Section 532.233 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE... and jobs to be covered in the wage survey. (2) Shall prepare a summary of the hearings and submit it...

9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

Science.gov (United States)

2010-01-01

... veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall provide adequate veterinary care to its animals in compliance with this section: (1) Each research facility shall...

Analysis of the running-in phase of a Passively Safe Thorium Breeder Pebble Bed Reactor

International Nuclear Information System (INIS)

Wols, F.J.; Kloosterman, J.L.; Lathouwers, D.; Hagen, T.H.J.J. van der

2015-01-01

Highlights: • This work analyzes important trends of the running-in phase of a thorium breeder PBR. • Depletion equations are solved for important actinides and a fission product pair. • Breeding U-233 is achieved in 7 years by cleverly adjusting the feed fuel enrichment. • A safety analysis shows the thorium PBR is passively safe during the running-in phase. - Abstract: The present work investigates the running-in phase of a 100 MW th Passively Safe Thorium Breeder Pebble Bed Reactor (PBR), a conceptual design introduced in previous equilibrium core design studies by the authors. Since U-233 is not available in nature, an alternative fuel, e.g. U-235/U-238, is required to start such a reactor. This work investigates how long it takes to converge to the equilibrium core composition and to achieve a net production of U-233, and how this can be accelerated. For this purpose, a fast and flexible calculation scheme was developed to analyze these aspects of the running-in phase. Depletion equations with an axial fuel movement term are solved in MATLAB for the most relevant actinides (Th-232, Pa-233, U-233, U-234, U-235, U-236 and U-238) and the fission products are lumped into a fission product pair. A finite difference discretization is used for the axial coordinate in combination with an implicit Euler time discretization scheme. Results show that a time dependent adjustment scheme for the enrichment (in case of U-235/U-238 start-up fuel) or U-233 weight fraction of the feed driver fuel helps to restrict excess reactivity, to improve the fuel economy and to achieve a net production of U-233 faster. After using U-235/U-238 startup fuel for 1300 days, the system starts to work as a breeder, i.e. the U-233 (and Pa-233) extraction rate exceeds the U-233 feed rate, within 7 years after start of reactor operation. The final part of the work presents a basic safety analysis, which shows that the thorium PBR fulfills the same passive safety requirements as the

48 CFR 5452.233-9001 - Disputes: Agreement To Use Alternative Dispute Resolution (ADR).

Science.gov (United States)

2010-10-01

... Alternative Dispute Resolution (ADR). 5452.233-9001 Section 5452.233-9001 Federal Acquisition Regulations... of Provisions and Clauses 5452.233-9001 Disputes: Agreement To Use Alternative Dispute Resolution... Alternative Dispute Resolution (ADR) (APR 2001)—DLAD (a) The parties agree to negotiate with each other to try...

Materials compatibility considerations for a fusion-fission hybrid reactor design

International Nuclear Information System (INIS)

DeVan, J.H.; Tortorelli, P.F.

1983-01-01

The Tandem Mirror Hybrid Reactor is a fusion reactor concept that incorporates a fission-suppressed breeding blanket for the production of 233 U to be used in conventional fission power reactors. The present paper reports on compatibility considerations related to the blanket design. These considerations include solid-solid interactions and liquid metal corrosion. Potential problems are discussed relative to the reference blanket operating temperature (490 0 C) and the recycling time of breeding materials (<1 year)

48 CFR 2852.233-70 - Protests filed directly with the Department of Justice.

Science.gov (United States)

2010-10-01

... with the Department of Justice. 2852.233-70 Section 2852.233-70 Federal Acquisition Regulations System DEPARTMENT OF JUSTICE Clauses and Forms SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 2852.233-70 Protests filed directly with the Department of Justice. As prescribed in 2833.102(d...

238U + n resolved resonance energies

International Nuclear Information System (INIS)

Olsen, D.K.; de Saussure, G.; Perez, R.B.; Difilippo, F.C.; Ingle, R.W.

1978-01-01

Neutron transmission measurements from 100 eV to 170 keV at 150 m through four 238 U samples are reported. The energy calibration is described, and the resultant 233 U resolved resonance energies are found to be intermediate between those from other workers. In addition, some energies for sharp resonances in 23 Na, 27 Al, 32 S, and 206 Pb are given

25 CFR 23.3 - Policy.

Science.gov (United States)

2010-04-01

... AFFAIRS, DEPARTMENT OF THE INTERIOR HUMAN SERVICES INDIAN CHILD WELFARE ACT Purpose, Definitions, and Policy § 23.3 Policy. In enacting the Indian Child Welfare Act of 1978, Pub. L. 95-608, the Congress has declared that it is the policy of this Nation to protect the best interests of Indian children and to...

Hydrolysis of U(VI) and sodium uranates

International Nuclear Information System (INIS)

Pongi, N.-K.; Double, Gerard; Hurwic, Jozef

1980-01-01

The potentiometric titration curves of UO 2 (NO 3 ) 2 aqueous solutions by NaOH have been interpreted. The results we have got verify and complete those published before. From isohydric species (UO 2 ) 3 (OH) 7 - , with pH = 7,8 and the experimental molar value of the relation xsub(i) = Na/U = 2.33, the following ionic and molecular species in acid medium have been deduced: (UO 2 ) 2 (OH) 2 2+ , (UO 2 ) 3 (OH) 2 2+ , (UO 2 ) 3 (OH) 5 + and (UO 2 ) 3 (OH) 6 . The composition of the precipitates corresponding to the particular points of the potentiometric titration curves, by chemical, thermal decomposition analysis and by X-rays diffraction, have been carried out: (UO 2 ) 6 (OH) 12 .6H 2 O, Na 2 U 8 O 25 , Na 2 U 6 O 19 , Na 2 U 4 O 13 and Na 2 U 2 O 7 for xsub(i) = 1,67 and 2.00, 2.23, 2.33, 2.52, 3.00 and over, respectively. The uranyl hydroxide was obtained for first time from an aqueous solution [fr

Neutron multipilication factors as a function of temperature: a comparison of calculated and measured values for lattices using 233UO2-ThO2 fuel in graphite

International Nuclear Information System (INIS)

Newman, D.F.; Gore, B.F.

1978-01-01

Neutron multiplication factors calculated as a function of temperature for three graphite-moderated 233 UO 2 -ThO 2 -fueled lattices are correlated with the values measured for these lattices in the high-temperature lattice test reactor (HTLTR). The correlation analysis is accomplished by fitting calculated values of k/sub infinity/(T) to the measured values using two least-squares-fitted correlation coefficients: (a) a normalization factor and (b) a temperature coefficient bias factor. These correlations indicate the existence of a negative (nonconservative) bias in temperature coefficients of reactivity calculated using ENDF/B-IV cross-section data. Use of an alternate cross-section data set for thorium, which has a smaller resonance integral than ENDF/B-IV data, improved the agreement between calculated and measured temperature coefficients of reactivity for the three experimental lattices. The results of the correlations are used to estimate the bias in the temperature coefficient of reactivity calculated for a lattice typical of fresh 233 U recycle fuel for a high-temperature gas-cooled reactor (HTGR). This extrapolation to a lattice having a heavier fissile loading than the experimental lattices is accomplished using a sensitivity analysis of the estimated bias to alternate thorium cross-section data used in calculations of k/sub infinity/(T). The envelope of uncertainty expected to contain the actual values for the temperature coefficient of the reactivity for the 233 U-fueled HTGR lattice studied remains negative at 1600 K (1327 0 C). Although a broader base of experimental data with improved accuracy is always desirable, the existing data base provided by the HTLTR experiments is judged to be adequate for the verification of neutronic calculations for the HTGR containing 233 U fuel at its current state of development

Thorium--uranium cycle ICF hybrid concept

International Nuclear Information System (INIS)

Frank, T.G.

1978-01-01

The results of preliminary studies of a laser-driven fusion-fission hybrid concept utilizing the 232 Th- 233 U breeding cycle are reported. Neutron multiplication in the breeding blanket is provided by a region containing 238 UO 2 and the equilibrium concentration of 239 PuO 2 . Established fission reactor technology is utilized to determine limits on operating conditions for high-temperature fuels and structures. The implications of nonproliferation policies for the operation of fusion-fission hybrid reactors are discussed

46 CFR 402.220 - Registration of pilots.

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Registration of pilots. 402.220 Section 402.220 Shipping... ORDERS Registration of Pilots § 402.220 Registration of pilots. (a) Each applicant pilot must complete the number of round trips specified in this section prior to registration as a U.S. registered pilot...

Thorium cycles and proliferation

International Nuclear Information System (INIS)

Lovins, A.B.

1979-01-01

This paper analyzes several prevalent misconceptions about nuclear fuel cycles that breed fissile uranium-233 from thorium. Its main conclusions are: U-233, despite the gamma radioactivity of associated isotopes, is a rather attractive material for making fission bombs, and is a credible material for subnational as well as national groups to use for this purpose; (2) pure thorium cycles, which in effect merely substitute U-233 for Pu, would take many decades and much U to establish, and offer no significant safeguards advantage over Pu, cycles; (3) denatured Th-U cycles, which dilute the U-233 with inert U-238 to a level not directly usable in bombs, are not an effective safeguard even against subnational bomb-making; (4) several other features of mixed Th-U cycles are rather unattractive from a safeguards point of view; (5) thus, Th cycles of any kind are not a technical fix for proliferation (national or subnational) and, though probably more safeguardable than Pu cycles, are less so than once-through U cycles that entail no reprocessing; (6) while thorium cycles have some potential technical advantages, including flexibility, they cannot provide major savings in nuclear fuel resources compared to simpler ways of saving neutrons and U; and (7) while advocates of nuclear power may find Th cycles worth exploring, such cycles do not differ fundamentally from U cycles in any of the respects--including safeguards and fuel resources--that are relevant to the broader nuclear debate, and should not be euphorically embraced as if they did

On the radiology of thorium-uranium electro breeding

International Nuclear Information System (INIS)

Gai, E.V.; Rabotnov, N.S.; Shubin, Y.N.

1995-01-01

Radiological problems arising in thorium-uranium electro-breeding with thorium accelerator target are discussed. Following radiological problems are discussed and evaluated in simplified model calculations: U-232 formation, accumulation of light Th isotopes in (n, xn) reactions on thorium target: accumulation of the same nuclides in final repository after alpha-decay of uranium isotopes. The qualitative comparison of U-Pu and U-Th fuel cycles is performed. The problems seem to be serious enough to justify detailed quantitative investigation. (authors)

An extraction method of uranium 233 from the thorium irradiates in a reactor core; Une methode d'extraction de l'uranium-233 a partir du thorium irradie dans une pile

Energy Technology Data Exchange (ETDEWEB)

Chesne, A; Regnaut, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

Description of the conditions of separation of the thorium, of the uranium 233 and of the protactinium 233 in hydrochloric solution by absorption then selective elution on anion exchange resin. A precipitation of the thorium by the oxalic acid permits the recuperation of the hydrochloric acid which is recycled, the main, raw material consumed being the oxalic acid. (authors) [French] Description des conditions de separation du thorium, de l'uranium 233 et du protactinium 233 en solution chlorhydrique par absorption puis elution selective sur resine echangeuse d'anions. Une precipitation du thoriun par l'acide oxalique permet la recuperation de l'acide chlorhydrique qui est recycle, la principale matiere premiere consommee etant l'acide oxalique. (auteurs)

Airplane pilot mental health and suicidal thoughts: a cross-sectional descriptive study via anonymous web-based survey.

Science.gov (United States)

Wu, Alexander C; Donnelly-McLay, Deborah; Weisskopf, Marc G; McNeely, Eileen; Betancourt, Theresa S; Allen, Joseph G

2016-12-15

The Germanwings Flight 9525 crash has brought the sensitive subject of airline pilot mental health to the forefront in aviation. Globally, 350 million people suffer from depression-a common mental disorder. This study provides further information on this important topic regarding mental health especially among female airline pilots. This is the first study to describe airline pilot mental health-with a focus on depression and suicidal thoughts-outside of the information derived from aircraft accident investigations, regulated health examinations, or identifiable self-reports, which are records protected by civil aviation authorities and airline companies. This is a descriptive cross-sectional study via an anonymous web-based survey administered between April and December 2015. Pilots were recruited from unions, airline companies, and airports via convenience sampling. Data analysis included calculating absolute number and prevalence of health characteristics and depression scores. One thousand eight hundred thirty seven (52.7%) of the 3485 surveyed pilots completed the survey, with 1866 (53.5%) completing at least half of the survey. 233 (12.6%) of 1848 airline pilots responding to the Patient Health Questionnaire 9 (PHQ-9), and 193 (13.5%) of 1430 pilots who reported working as an airline pilot in the last seven days at time of survey, met depression threshold-PHQ-9 total score ≥ 10. Seventy-five participants (4.1%) reported having suicidal thoughts within the past two weeks. We found a significant trend in proportions of depression at higher levels of use of sleep-aid medication (trend test z = 6.74, p sexual harassment (z = 3.18, p = 0.001) or verbal harassment (z = 6.13, p < 0.001). Hundreds of pilots currently flying are managing depressive symptoms perhaps without the possibility of treatment due to the fear of negative career impacts. This study found 233 (12.6%) airline pilots meeting depression threshold and 75 (4.1%) pilots

Organic breeding: New trend in plant breeding

Directory of Open Access Journals (Sweden)

Berenji Janoš

2009-01-01

Full Text Available Organic breeding is a new trend in plant breeding aimed at breeding of organic cultivars adapted to conditions and expectations of organic plant production. The best proof for the need of organic cultivars is the existence of interaction between the performances of genotypes with the kind of production (conventional or organic (graph. 1. The adaptation to low-input conditions of organic production by more eddicient uptake and utilization of plant nutrients is especially important for organic cultivars. One of the basic mechanism of weed control in organic production is the competition of organic cultivars and weeds i.e. the enhanced ability of organic cultivars to suppress the weeds. Resistance/tolerance to diseases and pests is among the most important expectations toward the organic cultivars. In comparison with the methods of conventional plant breeding, in case of organic plant breeding limitations exist in choice of methods for creation of variability and selection classified as permitted, conditionally permitted and banned. The use of genetically modified organisms and their derivated along with induced mutations is not permitted in organic production. The use of molecular markers in organic plant breeding is the only permitted modern method of biotechnology. It is not permitted to patent the breeding material of organic plant breeding or the organic cultivars. .

45 CFR 233.28 - Monthly reporting.

Science.gov (United States)

2010-10-01

... ELIGIBILITY IN FINANCIAL ASSISTANCE PROGRAMS § 233.28 Monthly reporting. (a) State plans specifying... information requested on the form, and provides a telephone number for this purpose; (4) Includes a statement, to be signed by the recipient, that he or she understands that the information he or she provides may...

40 CFR 233.11 - Program description.

Science.gov (United States)

2010-07-01

... organization and structure of the State agency (agencies) which will have responsibility for administering the... under § 233.10 shall include: (a) A description of the scope and structure of the State's program. The... will coordinate its enforcement strategy with that of the Corps and EPA; (h) A description of the...

Project of a binary breeder reactor and its inherent safety

International Nuclear Information System (INIS)

Nascimento, J.A. do; Dias, A.F.; Ishiguro, Y.

1983-01-01

A core layout for the binary breeder reactor (BBR) is developed based on the results of preliminary burnup calculations. The apparent breeding ratio, in the U 233 /Th fueled inner core, is low due to the accumulation of Pa-233 in the first few months of operation. The loss of reactivity during this time is around 3%. The BBR requires more reactivity control than Pu/U-fueled LMFBRs and the core layout developed has 19 control rod assemblies in the inner core. Three aspects related to the inherent safety of the Binary Breeder Reactor have been studied: the radial distribution of the sodium-void reactivity zone-wise Doppler reactivity and the fractions of delayed neutrons. The results show excellent characteristics for the BRB safety. (Author) [pt

Project of a binary breeder reactor and its inherent safety

International Nuclear Information System (INIS)

Nascimento, J.A. do; Dias, A.F.; Ishiguro, Y.

1983-01-01

A core layout for the binary breeder reactor (BBR) is developed based on the results of preliminary burnup calculations. In the U 233 /TH fueled inner core, the apparent breeding ratio is low due to the accumulation of Pa-233 in the first few months of operation. The loss of reactivity during this time is approximatelly 3%. The BBR requires more reactivity control than Pu/U-fueled LMFBRs and the core layout developed has 19 control rod assemblies in the inner core. Three aspects related to the inherent safety of the BBR have been studied: radial distribution of the sodium-void reactivity, zone-wise Doppler reactivity, and the delayed neutron fractions. Results show excellent safety characteristics of the BBR. (Author) [pt

76 FR 50715 - Briefing on Partner Vetting System Pilot Program

Science.gov (United States)

2011-08-16

... Development Briefing on Partner Vetting System Pilot Program AGENCY: U.S. Department of State and U.S. Agency... briefing on the Partner Vetting System (PVS) pilot program. The objective of the briefing is to provide information about the PVS pilot program. Members of the public may attend in person or join via teleconference...

38 CFR 21.5290 - Educational Assistance Pilot Program.

Science.gov (United States)

2010-07-01

... Pilot Program. 21.5290 Section 21.5290 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... Assistance Under 38 U.S.C. Chapter 32 Educational Assistance Pilot Program § 21.5290 Educational Assistance Pilot Program. (a) Purpose. The Educational Assistance Pilot Program is designed to encourage...

A road map for the realization of global-scale thorium breeding fuel cycle by single molten-fluoride flow

International Nuclear Information System (INIS)

Furukawa, K.; Arakawa, K.; Erbay, L. B.

2007-01-01

For global survival in this century, we urgently need to launch a completely new global nuclear fission industry. To get worldwide public acceptance of nuclear energy, improvements are essential not only on safety, radio-waste management and economy but also especially nuclear proliferation resistance and safeguards. However, such global fission industry cannot replace the present fossil fuel industry in the next 50 years, unless the doubling-time of nuclear energy is less than 10 years, preferably 5-7 years. Such a doubling-time cannot be established by any kind of classical 'Fission Breeding Power Station' concept. We need a symbiotic system which couples fission power reactors with a system which can convert fertile thorium to fissile U-233, such as a spallation or D/T fusion (if and when it becomes available). For such a purpose, THORIMS-NES [Thorium Molten-Salt Nuclear Energy Synergetic System] has been proposed, which is composed of simple thermal fission power stations (FUJI) and fissile producing Accelerator Molten-Salt Breeder (AMSB). Its system functions are very ambitious, delicate and complex, but can be realized in the form of simple hardware applying the multifunctional 'single-phase molten-fluoride' circulation system. This system has no difficulties relating with 'radiation-damage', 'heat-removal' and 'chemical processing' owing to the simple 'idealistic ionic liquid' character. FUJI is size-flexible (economical even in smaller sizes), fuel self-sustaining without any continuous chemical processing and without core-graphite replacement, and AMSB is based on a single-fluid molten-salt target/blanket concept, which solves most engineering difficulties such as radiation-damage, heat-removal etc., except high-current proton accelerator development. Several AMSBs are accommodated in the regional centers (several ten sites in the world) with batch chemical processing plants including radio-waste management. The integrated thorium breeding fuel cycle is

76 FR 56262 - Community Advantage Pilot Program

Science.gov (United States)

2011-09-12

... SMALL BUSINESS ADMINISTRATION [Docket No. SBA 2011-0003] Community Advantage Pilot Program AGENCY: U.S. Small Business Administration (SBA). ACTION: Notice of change to Community Advantage Pilot... Community Advantage Pilot Program. In that notice, SBA modified or waived as appropriate certain regulations...

75 FR 80561 - Community Express Pilot Program

Science.gov (United States)

2010-12-22

... SMALL BUSINESS ADMINISTRATION Community Express Pilot Program AGENCY: U.S. Small Business Administration (SBA). ACTION: Notice of short-term extension and termination of the Community Express Pilot Program. SUMMARY: This notice announces the termination of the Community Express Pilot Program following a...

75 FR 473 - Community Express Pilot Program

Science.gov (United States)

2010-01-05

... SMALL BUSINESS ADMINISTRATION Community Express Pilot Program AGENCY: U.S. Small Business Administration (SBA). ACTION: Notice of extension of the Community Express Pilot Program. SUMMARY: This notice extends the Community Express Pilot Program in its current form through December 31, 2010. Based upon the...

39 CFR 233.3 - Mail covers.

Science.gov (United States)

2010-07-01

.... For purpose of these regulations, the following terms are hereby defined. (1) Mail cover is the... criminal law. (3) When time is of the essence, the Chief Postal Inspector, or designee, may act upon an... furnish information as defined in § 233.3(c)(1) to any person, except as authorized by a mail cover order...

Transformation temperatures γU → δUZr2 Y γU →αU in U-Zr-Nb alloys

International Nuclear Information System (INIS)

Komar Varela, Carolina L.; Arico, Sergio F.; Gribaudo, Luis M.; Comision Nacional de Energia Atomica, General San Martin

2009-01-01

The international RERTR program has as primary objective the development of new fuels for research and test reactors to satisfy the requirement of low enrichment in 235 U (lower than 20 %). It is known that the cubic-phase (γU) has an excellent behaviour under irradiation. In this context, in the Materials Department (GIDAT-GAEN-CNEA) U-Zr-Nb alloys are considered candidates for the development of a high-density monolithic-type nuclear fuel. It is necessary to evaluate the thermodynamic parameters that allow to obtain a range of concentrations of the U-Zr-Nb system in which this phase can be retained in the metastable condition with the required 235 U density. In this work, eight U alloys with concentrations ranging from 13.9 to 43.7 wt.% Zr and from 0 to 6.4 wt.% Nb, were fabricated. Dynamical measurements of electrical resistivity, with a cooling rate of 4 o C/min, were performed and the results were analyzed. Considering this cooling rate, a Nb concentration of at least 17.8 wt. % would inhibit the transformation γU→ δUZr 2 and a concentration of al least 23.3 wt % would inhibit the γU → αU transformation. (author)

Proximate analysis of two breeds of goat meat (chevon) and assessment of perception on goat consumption

Science.gov (United States)

Baharuddin, Azan Azuwan; Abdullah, Aminah

2015-09-01

Goat Meat (chevon) has been used as a source of protein and its demand for consumption is increasing yearly in Malaysia. The objective of the research was to determine proximate composition namely moisture, protein, fat and ash level in chevon from different type of breed i.e. Boer and Katjang. The goat breed proximate analyses were compared with sheep meat (mutton). The results for goat breeds were showing that the percentage of moisture, fat, protein and ash were of 73.06 - 74.99, 2.76 - 2.94, 20.81 - 22.47 and 0.97 - 1.21 respectively. Meanwhile the concentration of moisture, fat, protein and ash for mutton were 73.52, 5.06, 22.50 and 1.17 respectively. The pilot study on perception survey indicated that the highest respondent percentage on consumption of chevon was once in a month. Based on the survey, Boer was the most known breed compared to the other breed. Majority of respondents reported that chevon was fairly expensive meat but easier to obtain in the survey area.

75 FR 39090 - Airport Privatization Pilot Program

Science.gov (United States)

2010-07-07

... Privatization Pilot Program AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Receipt and... pilot program received under 49 U.S.C. Section 47134. The preliminary application is accepted for review... operator, negotiate an agreement and submit a final application to the FAA for exemption under the pilot...

Production of U3O8 by uranyl formate precipitation and calcination in a full-scale pilot facility

International Nuclear Information System (INIS)

Kendrick, L.S.; Wilson, W.A.; Mosley, W.C.

1984-08-01

The uranyl formate process for the production of U 3 O 8 with a controlled particle size has been extensively studied on a laboratory scale. Based on this study, a pilot-scale facility (the Uranyl Formate Facility) was built to investigate the key steps of the process on a larger scale. These steps were the precipitation of a uranyl formate monohydrate salt and the calcination of this salt to U 3 O 8 . Tests of the facility and process were conducted at conditions recommended by the laboratory-scale studies for a full-scale production facility. These tests demonstrated that U 3 O 8 of the required particle size for the PM process can be produced on a plant scale by the calcination of uranyl formate crystals. The performance of the U 3 O 8 produced by the uranyl formate process in fuel tube fabrication was also investigated. Small-scale extrusion tests of U 3 O 8 -Al cores which used the U 3 O 8 produced in the Uranyl Formate Facility were conducted. These tests demonstrated that the U 3 O 8 quality was satisfactory for the PM process

Plant Breeding and Genetics Newsletter, No. 38, January 2017

International Nuclear Information System (INIS)

2017-01-01

This year significant progress was made on the discovery of mutations using next generation sequencing for different crops, including rice and banana. Also, a program for the development of molecular markers for important traits has been initiated to translate the molecular knowledge on mutant traits into applications for plant breeding and to enable wider utilization of available useful mutant germplasm by Member States. A semi-dwarf mutant trait in sorghum was chosen in the pilot phase. In October 2016, a film crew visited the Agency’s Laboratories in Seibersdorf, including PBGL, in the context of a National Geographics project on the application of nuclear technologies to help address global challenges such as food, agriculture and climate change. In December 2016 a 22-minute documentary was aired on the National Geographics Channel in Belgium, the Netherlands and France highlighting the work at PBGL and the contribution of plant mutation breeding to food security and climate-smart agriculture.

Summary of Pilot-Scale Activities with Mercury Contaminated Sludges (U)

International Nuclear Information System (INIS)

Cicero, C.A.; Hutson, N.D.; Zamecnik, J.R.; Smith, M.E.; Miller, D. H.; Ritter, J.A.; Hardy, B.J.; Jantzen, C.M.

1995-01-01

Technologies for treatment of low level mixed wastes (LLMW) are currently being investigated by the Mixed Waste Focus Area (MWFA) of the Department of Energy (DOE). The Savannah River Technology Center (SRTC) has been chartered by the MWFA to study vitrification treatment of the wastes through an Office of Technology Development (OTD) Technical Task Plan (TTP). SRTC's efforts have included crucible-scale studies and pilot-scale testing on simulated LLMW sludges, resins, soils, and other solid wastes. Results from the crucible-scale studies have been used as the basis for the pilot-scale demonstrations. One of the streams to be investigated in fiscal year (FY) 1995 by SRTC was a mercury waste. In FY 1995, SRTC performed crucible-scale studies with mercury contaminated soil. This waste stream was selected because of the large number of DOE sites that have an inventory of contaminated or hazardous soil. More importantly, it was readily available for treatment. Pilot-scale studies were to be completed in FY 1995, but could not be completed due to a reduction in funding. Since the main driver for focusing on a mercury waste stream was to determine how the mercury could be treated, a compilation of pilot-scale tests with mercury sludges performed under the guidance of SRTC is provided in this report. The studies summarized in this report include several pilot-scale vitrification demonstrations with simulated radioactive sludges that contained mercury. The pilot-scale studies were performed at the SRTC in the Integrated Defense Waste Processing Facility (DWPF) Melter System (IDMS). The studies involved complete glass and offgas product characterization. Future pilot-scale studies with mercury streams will likely be performed with mercury contaminated soils, sediments, or sludges because of the need to dispose of this technically challenging waste stream. (Abstract Truncated)

Apparatus for power and breeding distribution measurements in breeder reactors

International Nuclear Information System (INIS)

Goldstein, N.P.; Sun, K.H.

1975-01-01

A detection system is disclosed herein for the measurement of power and breeding distribution inside a breeder reactor. Small diameter BeO balls comprising oxides of 235 U and 238 U are inserted into the reactor for activation and withdrawn to be counted in a Ge(Li) counter. Measurements of the activated fission and 239 Np gamma rays yield the desired distributions. (Official Gazette)

75 FR 77935 - Patriot Express Pilot Loan Initiative

Science.gov (United States)

2010-12-14

... SMALL BUSINESS ADMINISTRATION Patriot Express Pilot Loan Initiative AGENCY: U.S. Small Business Administration (SBA). ACTION: Notice of extension of the Patriot Express Pilot Loan Initiative. SUMMARY: This notice extends the Patriot Express Pilot Loan Initiative in its current form through December 31, 2013...

Analysis of the Gas Core Actinide Transmutation Reactor (GCATR)

Science.gov (United States)

Clement, J. D.; Rust, J. H.

1977-01-01

Design power plant studies were carried out for two applications of the plasma core reactor: (1) As a breeder reactor, (2) As a reactor able to transmute actinides effectively. In addition to the above applications the reactor produced electrical power with a high efficiency. A reactor subsystem was designed for each of the two applications. For the breeder reactor, neutronics calculations were carried out for a U-233 plasma core with a molten salt breeding blanket. A reactor was designed with a low critical mass (less than a few hundred kilograms U-233) and a breeding ratio of 1.01. The plasma core actinide transmutation reactor was designed to transmute the nuclear waste from conventional LWR's. The spent fuel is reprocessed during which 100% of Np, Am, Cm, and higher actinides are separated from the other components. These actinides are then manufactured as oxides into zirconium clad fuel rods and charged as fuel assemblies in the reflector region of the plasma core actinide transmutation reactor. In the equilibrium cycle, about 7% of the actinides are directly fissioned away, while about 31% are removed by reprocessing.

76 FR 7098 - Dealer Floor Plan Pilot Program

Science.gov (United States)

2011-02-09

... Plan Pilot Program AGENCY: U.S. Small Business Administration (SBA). ACTION: Program implementation with request for comments. SUMMARY: SBA is introducing a new Dealer Floor Plan Pilot Program to make... Plan Pilot Program was created in the Small Business Jobs Act of 2010. Under the new Dealer Floor Plan...

Personality Test Scores that Distinguish U.S. Air Force Remotely Piloted Aircraft Drone Pilot Training Candidates

Science.gov (United States)

2014-02-18

advancement of aviation drone technology has led to significant developments and improvements in the capabilities of military remotely piloted aircraft...stress; less excitement seeking and action oriented; less assertive; more socially introverted and withdrawn; more socially compliant and...to age and educational differences. Fifth, evaluations that involve selection and assessment of pilot applicants should include collateral sources of

Breeds of cattle

NARCIS (Netherlands)

Buchanan, David S.; Lenstra, Johannes A.

2015-01-01

This chapter gives an overview on the different breeds of cattle (Bos taurus and B. indicus). Cattle breeds are presented and categorized according to utility and mode of origin. Classification and phylogeny of breeds are also discussed. Furthermore, a description of cattle breeds is provided.

Production of 232,233Pa in 6Li+232Th Collisions in the Classical Trajectory Approach

International Nuclear Information System (INIS)

Aleshin, V.P.

2000-01-01

The semiclassical model of nuclear reactions with loosely bound projectiles (V.P. Aleshin, B.I. Sidorenko, Acta Phys. Pol. B29, 325 (1998)) is refined and compared with experimental data of Rama Rao et al. on the excitation function for the production of 232,233 Pa in 6 Li+ 232 Th collisions at E = 30-50 MeV. The main contribution to the production of 232 Pa is the 2 neutron emission from excited states of 234 Pa formed in the ( 6 Li,α) reaction. The main source of 233 Pa is the ( 6 Li,αp) reaction followed by γ transitions from excited states of 233 Th to 233 Th (g.s.) which transforms to 233 Pa through β - decay. The ground state of 6 Li regarded as a combination of n+p+α is modeled with the K=2, l x =l y =0 hyperspherical function. The calculation underpredicts the excitation function of 232 Pa by a factor of 0.6 and overpredicts the excitation function of 233 Pa by a factor of 2.3, on the average. With the more realistic wave function of 6 Li both factors are expected to be closer to 1. (author)

Site-Specific Health and Safety Plan, 233-S Decontamination and Decommissioning

International Nuclear Information System (INIS)

Hobbs, B.J.

1998-01-01

The 233-S Facility operated from January 1952 until July 1967, at which time the building entered the U.S. Department of Energy's Surplus Facility Management Program as a retired facility. The facility has since undergone severe degradation due to exposure to extreme weather conditions. A freeze and thaw cycle occurred at the Hanford Site during February 1996, which caused cracking failure of portions of the building roof. This resulted in significant infiltration of water into the facility, which creates a pathway for potential release of radioactive material into the environment (air and/or ground). Additionally, the weather caused existing cracks in concrete structures of the building to lengthen, thereby increasing the potential for failed confinement of the building's radioactive material. Differential settlement has also occurred, causing portions of the facility to separate from the main building structure, increasing the potential for release of radioactive material to the environment. An expedited response is proposed to remove this threat and ensure protection of human health and the environment

Validation of deep freezing of pilot samples for checking of time stability of indirect analyses of basic milk composition and for their long shelf-life

Directory of Open Access Journals (Sweden)

Oto Hanuš

2008-01-01

Full Text Available Essential part of raw milk component measurement is indirect infraanalyse. The checking of time measurement stability is important there. The preparation of pilot samples was described. Information about deep frozen milk pilot sample stability are sporadic. Aim of this work was to verify the stability of long-term stored and deep frozen pilot samples (FPSs. Pilot samples were frozen in liquid nitrogen bath −196 °C and after that stored at −21 °C for one month (A and more months (B till analyse. The pilot samples were measured by CombiFoss 6000: fat F (%; protein CP (%; lactose L (%; casein C (%; solid non fat SNF (%; urea U (mg/100ml; somatic cell count SCC (ths./ml. In the short-term (A experiment the impact of freezing on pilot milk samples was relatively small, in the framework of acceptable value of repeatability (±0.02 % for components. The stability of values of FPSs was better according to standard deviations for important F evaluation in H (Holstein breed samples. The repeatability of values of FPSs in the time was very good for other components. The repeatability was better for SCC in J (Jersey breed samples (±16.5 thousands/ml. That is why the higher variability (±30.1 thousands/ml in H sample is visible less sceptically. The apparent result trends were not observable in the repeatability development of important milk indicators in FPSs. The mild trend was only in CP, but this trend covered absolutely very small shift (variation range. There are only oscillations, which are similar between J and H samples. It is possible to attribute these oscillations rather to instrument effects than to sample effects. The oscilations were markedly higher in the long-term (B experiment. Between J and H samples the oscilations were very similar in curves F and L. It is also possible to attribute them more to instrumental effects. The repeatability values (standard deviations sd of FPSs were mostly lower than ±0.06 %. It is acceptable for

90% Compliance Pilot Studies Final Report

Energy Technology Data Exchange (ETDEWEB)

None

2013-06-01

In early 2010, the U.S. Department of Energy (DOE) announced an opportunity for states to participate in energy code compliance evaluation pilot studies. DOE worked with five Regional Energy Efficiency Organizations (REEOs, formerly referred to as Energy Efficiency Partnerships, or EEPs) to fund pilot studies covering nine states. This report details conclusions stated in individual state reports, as well as conclusions drawn by DOE based on their oversight of the pilot studies, and based on discussions held with the REEOs and representatives from the pilot study states and their contractors.

Core Design and Deployment Strategy of Heavy Water Cooled Sustainable Thorium Reactor

Directory of Open Access Journals (Sweden)

Naoyuki Takaki

2012-08-01

Full Text Available Our previous studies on water cooled thorium breeder reactor based on matured pressurized water reactor (PWR plant technology concluded that reduced moderated core by arranging fuel pins in a triangular tight lattice array and using heavy water as coolant is appropriate for achieving better breeding performance and higher burn-up simultaneously [1–6]. One optimum core that produces 3.5 GW thermal energy using Th-²³³U oxide fuel shows a breeding ratio of 1.07 and averaged burn-up of about 80 GWd/t with long cycle length of 1300 days. The moderator to fuel volume ratio is 0.6 and required enrichment of ²³³U for the fresh fuel is about 7%. The coolant reactivity coefficient is negative during all cycles despite it being a large scale breeder reactor. In order to introduce this sustainable thorium reactor, three-step deployment scenario, with intermediate transition phase between current light water reactor (LWR phase and future sustainer phase, is proposed. Both in transition phase and sustainer phase, almost the same core design can be applicable only by changing fissile materials mixed with thorium from plutonium to ²³³U with slight modification in the fuel assembly design. Assuming total capacity of 60 GWe in current LWR phase and reprocessing capacity of 800 ton/y with further extensions to 1600 ton/y, all LWRs will be replaced by heavy water cooled thorium reactors within about one century then thorium reactors will be kept operational owing to its potential to sustain fissile fuels while reprocessing all spent fuels until exhaustion of massive thorium resource.

Cognitive Evaluation of Israeli Air Force Pilot Cadets.

Science.gov (United States)

Gordon, Shirley; Goren, Chen; Carmon, Erez; Shelef, Leah

2017-04-01

In aviation psychology, there is a constant need for the cognitive evaluation of pilots as part of operational fitness and safety criteria. A cross-sectional study with comparison between the performance of Israeli Air Force pilot cadets (N = 318) and U.S. Air Force pilot training candidates (N = 512) as assessed by a cognitive battery was undertaken. The data of the comparison group was collected from Callister, King, and Retzlaff, as published in 1996. In general, the means in the three components composing the battery-speed, accuracy, and throughput variables-indicated that the Israeli Air Force pilot cadets' scores were higher than those of the U.S. Air Force pilot candidates' scores in 50 of 53 variables. Nonsignificant differences were found in Accuracy of shifting attention-arrow color (SATAC), pathfinder-combined (PFC), and pathfinder-letter (PFL). The difference in performance between the two groups may be due to differences in population characteristics. However, these results need to be considered cautiously, as the groups were sampled at a sizeable time gap (1996 for the U.S. Air Force vs. 2013 for the Israeli Air Force), with each time period characterized by different cultural and technological influences.Gordon S, Goren C, Carmon E, Shelef L. Cognitive evaluation of Israeli Air Force pilot cadets. Aerosp Med Hum Perform. 2017; 88(4):392-398.

"Boldness" in the domestic dog differs among breeds and breed groups.

Science.gov (United States)

Starling, Melissa J; Branson, Nicholas; Thomson, Peter C; McGreevy, Paul D

2013-07-01

"Boldness" in dogs is believed to be one end of the shy-bold axis, representing a super-trait. Several personality traits fall under the influence of this super-trait. Previous studies on boldness in dogs have found differences among breeds, but grouping breeds on the basis of behavioural similarities has been elusive. This study investigated differences in the expression of boldness among dog breeds, kennel club breed groups, and sub-groups of kennel club breed groups by way of a survey on dog personality circulated among Australian dog-training clubs and internet forums and lists. Breed had a significant effect on boldness (F=1.63, numDF=111, denDF=272, ppurpose. Retrievers were significantly bolder than flushing and pointing breeds (Reg. Coef.=2.148; S.E.=0.593; pdogs. Differences in boldness among groups and sub-groups suggest that behavioural tendencies may be influenced by historical purpose regardless of whether that purpose still factors in selective breeding. Copyright © 2013 Elsevier B.V. All rights reserved.

Costs of electronuclear fuel production

International Nuclear Information System (INIS)

Flaim, T.; Loose, V.

1978-07-01

The Los Alamos Scientific Laboratory (LASL) proposes to study the electronuclear fuel producer (EFP) as a means of producing fissile fuel to generate electricity. The main advantage of the EFP is that it may reduce the risks of nuclear proliferation by breeding 233 U from thorium, thereby avoiding plutonium separation. A report on the costs of electronuclear fuel production based upon two designs considered by LASL is presented. The findings indicate that the EFP design variations considered are not likely to result in electricity generation costs as low as the uranium fuel cycle used in the US today. At current estimates of annual fuel output (500 kg 233 U per EFP), the costs of electricity generation using fuel produced by the EFP are more than three times higher than generating costs using the traditional fuel cycle. Sensitivity analysis indicates that electronuclear fuel production would become cost competitive with the traditional uranium fuel cycle when U 3 O 8 (yellowcake) prices approach $1000 per pound

77 FR 40938 - Pilot Program on NAFTA Trucking Provisions

Science.gov (United States)

2012-07-11

...-0097] Pilot Program on NAFTA Trucking Provisions AGENCY: Federal Motor Carrier Safety Administration... Morales Guevara (DBA Fletes Morales) which applied to participate in the Agency's long-haul pilot program...] its intent to proceed with the initiation of a U.S.-Mexico cross-border long-haul trucking pilot...

Induction of keratinocyte migration by ECa 233 is mediated through FAK/Akt, ERK, and p38 MAPK signaling.

Science.gov (United States)

Singkhorn, Sawana; Tantisira, Mayuree H; Tanasawet, Supita; Hutamekalin, Pilaiwanwadee; Wongtawatchai, Tulaporn; Sukketsiri, Wanida

2018-03-13

Centella asiatica is widely considered the most important medicinal plant for treating and relieving skin diseases. Recently developed standardized extract of Centella asiatica ECa 233 has demonstrated positive effects on wound healing of incision and burn wound in rats. However, knowledge associated with wound healing mechanism of ECa 233 was scare. Therefore, this study aimed to investigate the effect and underlying molecular mechanisms of ECa 233 on the migration of a human keratinocyte cell line (HaCaT) using scratch wound healing assay. Formation of filopodia, a key protein in cell migration as well as signaling pathways possibly involved were subsequently assessed. It was found that HaCaT cell migration was significantly enhanced by ECa 233 in a concentration- and time-dependent manner. The filopodia formations were accordingly increased in exposure to ECa 233 at concentrations of 0.1-100 μg/ml. Furthermore, ECa 233 was found to significantly upregulate the expression of Rac1 and RhoA and to induce phosphorylation of FAK and Akt as well as ERK and p38 MAPK. Taken all together, it is suggestive that ECa 233 induces cell migration and subsequently promotes wound healing activity, through the activation of FAK, Akt, and MAPK signaling pathways thereby supporting the role of ECa 233 to be further developed for the clinical treatment of wound. Copyright © 2018 John Wiley & Sons, Ltd.

Limitations on the precision of 238U/235U measurements and implications for environmental monitoring

International Nuclear Information System (INIS)

Russ III, G.P.

1997-01-01

The ability to determine the isotopic composition of uranium in environmental samples is an important component of the International Atomic Energy Agency's (IAEA) safeguards program, and variations in the isotopic ratio 238 U/ 235 U provide the most direct evidence of isotopic enrichment activities. The interpretation of observed variations in 238 U/ 235 U depends on the ability to distinguish enrichment from instrumental biases and any variations occurring in the environment but not related to enrichment activities. Instrumental biases that have historically limited the accuracy of 238 U/ 235 U determinations can be eliminated by the use of the 233 U/ 236 U double-spike technique. With this technique, it is possible to determine the 238 U/ 235 U in samples to an accuracy equal to the precision of the measurement, ca. 0.1% for a few 10's of nanograms of uranium. Given an accurate determination of 238 U/ 235 U, positive identification of enrichment activities depends on the observed value being outside the range of 238 U/ 235 U's expected as a result of natural or environmental variations. Analyses of a suite of soil samples showed no variation beyond 0.2% in 238 U/ 235 U

Notice of release of iceberg, romaine, and leaf lettuce breeding lines with improved disease resistance

Science.gov (United States)

The Agricultural Research Service, U.S. Department of Agriculture announces the release of sixteen breeding lines of lettuce (Lactuca sativa L.). Five (SM13-Il, SM13-I2, SM13-I3, SM13-I4, and SM13-I5) of the six iceberg breeding lines can be used for whole head or salad blend production; the sixth i...

76 FR 56868 - Pilot Project on NAFTA Trucking Provisions

Science.gov (United States)

2011-09-14

...-0097] Pilot Project on NAFTA Trucking Provisions AGENCY: Federal Motor Carrier Safety Administration... that have applied to participate in the Agency's long- haul pilot program to test and demonstrate the... proceed with the initiation of a U.S.-Mexico cross-border long-haul trucking pilot program to test and...

77 FR 27837 - Pilot Program on NAFTA Trucking Provisions

Science.gov (United States)

2012-05-11

...-0097] Pilot Program on NAFTA Trucking Provisions AGENCY: Federal Motor Carrier Safety Administration... carriers that applied to participate in the Agency's long- haul pilot program to test and demonstrate the... intent to proceed with the initiation of a U.S.-Mexico cross-border long-haul trucking pilot program to...

76 FR 73765 - Pilot Project on NAFTA Trucking Provisions

Science.gov (United States)

2011-11-29

...-0097] Pilot Project on NAFTA Trucking Provisions AGENCY: Federal Motor Carrier Safety Administration... that have applied to participate in the Agency's long- haul pilot program to test and demonstrate the... proceed with the initiation of a U.S.-Mexico cross-border long-haul trucking pilot program to test and...

Development of breeding objectives for beef cattle breeding ...

African Journals Online (AJOL)

Mnr J F Kluyts

However, to solve the simultaneous equations the ... The aggregate breeding value represents a fundamental concept, the breeding objective, which is ..... Two properties characterise a linear programming problem. The first is additivity, ...

Engineering evaluation/cost analysis for the 233-S Plutonium Concentration Facility

International Nuclear Information System (INIS)

1997-01-01

The deactivated 233-S Plutonium Concentration Facility (233-S Facility) is located in the 200 Area. The facility has undergone severe degradation due to exposure to extreme weather conditions. A rapid freeze and thaw cycle occurred at the Hanford Site during February 1996, which caused cracking to occur on portions of the building's roof. This has resulted in significantly infiltration of water into the facility, which provides a pathway for potential release of radioactive material into the environment (air and/or ground). The weather caused several existing cracks in the concrete portions of the structure to lengthen, increasing the potential for failed confinement of the radioactive material in the building. Differential settlement has also occurred, causing portions of the facility to separate from the main building structure thus creating a potential for release of radioactive material t the environment. An expedited removal action is proposed to ensure that a release from the 233-S Facility does not occur. The US Department of Energy (DOE), Richland Operations Office (RL), in cooperation with the EPA, has prepared this Engineering Evaluation/Cost Analysis (EE/CA) pursuant to CERCLA. Based on the evaluation, RL has determined that hazardous substances in the 233-S Facility may present a potential threat to human health and/or the environment, and that an expedited removal action is warranted. The purpose of the EE/CA is to provide the framework for the evaluation and selection of a technology from a viable set of alternatives for a removal action

Fuel cycles and advanced core designs for the Gas-Cooled Fast Breeder Reactor

International Nuclear Information System (INIS)

Simon, R.H.; Hamilton, C.J.; Hunter, R.S.

1982-01-01

Studies indicate that a 1200 MW(e) Gas-Cooled Fast Breeder Reactor could achieve compound system doubling times of under ten years when using advanced oxide or carbide fuels. In addition, when thorium is used in the breeding blankets, enough U-233 can be generated in each GCFR to supply several advanced converter reactors with fissionable material and this symbiotic relationship could provide energy for the world for centuries. (author)

Motivation and Resolve of U.S. Air Force Pilot Candidates

Science.gov (United States)

2017-06-15

demonstrated character and emotional composure (stability), and a consistent desire and proven resolve to become, and remain, a pilot ( motivation ). MFS-N... motivation used at MFS-N. The goals of this research are to better understand what motivates pilot candidates to pursue aviation careers and to establish...baseline motivation and grit scores. These scores can then be utilized, in conjunction with other MFS-N testing information, to understand pre-morbid

48 CFR 352.233-71 - Litigation and claims.

Science.gov (United States)

2010-10-01

... the action in good faith. The Government shall not be liable for the expense of defending any action... compensated by insurance which was required by law or regulation or by written direction of the Contracting... FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 352.233-71 Litigation...

GLOBE Aerosol Field Campaign - U.S. Pilot Study 2016

Science.gov (United States)

Pippin, Margaret; Marentette, Christina; Bujosa, Robert; Taylor, Jessica; Lewis, Preston

2016-01-01

During the spring of 2016, from April 4 - May 27, sixteen GLOBE schools participated in the GLOBE Aerosol Field Campaign - U.S. Pilot Study. Thirteen teachers from these schools had previously participated in the NASA LEARN program (Long-term Experience in Authentic Research with NASA) where they were GLOBE trained in Atmosphere protocols, and engaged in 1-3 years of research under the mentorship of NASA scientists. Each school was loaned two aerosol instruments for the Campaign duration, either 2 GLOBE sun photometers, 2 Calitoo sun photometers, or 1 of each. This allowed for students to make measurements side-by-side and in the case of the Calitoos, to compare AOT results immediately with each other for better consistency in data collection. Additionally, as part of the Field Campaign evaluation, multiple instruments allow for an assessment of the ease of use of each instrument for grade level of students, whether in middle school or high school. Before the Campaign, all GLOBE and Calitoo instruments were 'checked out' against an AERONET, then checked again upon return after the Campaign. By examining all data, before, during and after the Campaign, this gives an indication of instrument performance and proficiency obtained by the students. Support was provided to each teacher and their students at the level requested, via email, phone or video conferencing.

Viability of the Alaskan breeding population of Steller’s eiders

Science.gov (United States)

Dunham, Kylee; Grand, James B.

2016-10-11

The U.S. Fish and Wildlife Service is tasked with setting objective and measurable criteria for delisting species or populations listed under the Endangered Species Act. Determining the acceptable threshold for extinction risk for any species or population is a challenging task, particularly when facing marked uncertainty. The Alaskan breeding population of Steller’s eiders (Polysticta stelleri) was listed as threatened under the Endangered Species Act in 1997 because of a perceived decline in abundance throughout their nesting range and geographic isolation from the Russian breeding population. Previous genetic studies and modeling efforts, however, suggest that there may be dispersal from the Russian breeding population. Additionally, evidence exists of population level nonbreeding events. Research was conducted to estimate population viability of the Alaskan breeding population of Steller’s eiders, using both an open and closed model of population process for this threatened population. Projections under a closed population model suggest this population has a 100 percent probability of extinction within 42 years. Projections under an open population model suggest that with immigration there is no probability of permanent extinction. Because of random immigration process and nonbreeding behavior, however, it is likely that this population will continue to be present in low and highly variable numbers on the breeding grounds in Alaska. Monitoring the winter population, which includes both Russian and Alaskan breeding birds, may offer a more comprehensive indication of population viability.

Sympatric breeding auks shift between dietary and spatial resource partitioning across the annual cycle.

Directory of Open Access Journals (Sweden)

Jannie Fries Linnebjerg

Full Text Available When species competing for the same resources coexist, some segregation in the way they utilize those resources is expected. However, little is known about how closely related sympatric breeding species segregate outside the breeding season. We investigated the annual segregation of three closely related seabirds (razorbill Alcatorda, common guillemot Uriaaalge and Brünnich's guillemot U. lomvia breeding at the same colony in Southwest Greenland. By combining GPS and geolocation (GLS tracking with dive depth and stable isotope analyses, we compared spatial and dietary resource partitioning. During the breeding season, we found the three species to segregate in diet and/or dive depth, but less in foraging area. During both the post-breeding and pre-breeding periods, the three species had an increased overlap in diet, but were dispersed over a larger spatial scale. Dive depths were similar across the annual cycle, suggesting morphological adaptations fixed by evolution. Prey choice, on the other hand, seemed much more flexible and therefore more likely to be affected by the immediate presence of potential competitors.

46 CFR 401.428 - Basic rates and charges for carrying a U.S. pilot beyond normal change point or for boarding at...

Science.gov (United States)

2010-10-01

... boarding point, the ship shall pay at the rate of $719 per day or part thereof, plus reasonable travel... normal change point or for boarding at other than the normal boarding point. 401.428 Section 401.428... carrying a U.S. pilot beyond normal change point or for boarding at other than the normal boarding point...

Alternative fuel cycles and non-proliferation aspects

International Nuclear Information System (INIS)

Kessler, G.

1980-10-01

The most important physical characteristics of the U/Pu and the Th/U fuel cycles and the technical data of the most significant converter reactors operating with Th/U fuel are outlined in the report. Near breeders as well as breeders with a thermal neutron spectrum are briefly discussed, and the potential of breeders with fast neutron spectra in the Th/U fuel is outlined. The essential criteria for the comparison of the alternative fuel cycles with the reference Pu/U cycle are the consumption of natural uranium, the numbers of U-233 producing and U-233 consuming converter reactors and the amounts of fission material transported and handled within the fuel cycle (reprocessing, refabrication). Although the alternative U/Th fuel cycles are feasible with some advantages and some disadvantages as compared to the reference U/Pu cycle, not much experience has so far been gathered with pilot plants of the fuel cycle. The respective status in reprocessing, refabrication and waste disposal is briefly discussed. Finally, a comparison of the risk potential inherent in secular storage is presented and questions of resistance to proliferation and of safeguards of the U/Th cycle are discussed

Slave Breeding

OpenAIRE

Sutch, Richard

1986-01-01

This paper reviews the historical work on slave breeding in the ante-bellum United States. Slave breeding consisted of interference in the sexual life of slaves by their owners with the intent and result of increasing the number of slave children born. The weight of evidence suggests that slave breeding occurred in sufficient force to raise the rate of growth of the American slave population despite evidence that only a minority of slave-owners engaged in such practices.

CASSAVA BREEDING I: THE VALUE OF BREEDING VALUE

Directory of Open Access Journals (Sweden)

Hernán Ceballos

2016-08-01

Full Text Available Breeding cassava relies on several selection stages (single row trial-SRT; preliminary; advanced; and uniform yield trials - UYT. This study uses data from 14 years of evaluations. From more than 20,000 genotypes initially evaluated only 114 reached the last stage. The objective was to assess how the data at SRT could be used to predict the probabilities of genotypes reaching the UYT. Phenotypic data from each genotype at SRT was integrated into the selection index (SIN used by the cassava breeding program. Average SIN from all the progenies derived from each progenitor was then obtained. Average SIN is an approximation of the breeding value of each progenitor. Data clearly suggested that some genotypes were better progenitors than others (e.g. high number of their progenies reaching the UYT, suggesting important variation in breeding values of progenitors. However, regression of average SIN of each parental genotype on the number of their respective progenies reaching UYT resulted in a negligible coefficient of determination (r2 = 0.05. Breeding value (e.g. average SIN at SRT was not efficient predicting which genotypes were more likely to reach the UYT stage. Number of families and progenies derived from a given progenitor were more efficient predicting the probabilities of the progeny from a given parent reaching the UYT stage. Large within-family genetic variation tends to mask the true breeding value of each progenitor. The use of partially inbred progenitors (e.g. S1 or S2 genotypes would reduce the within-family genetic variation thus making the assessment of breeding value more accurate. Moreover, partial inbreeding of progenitors can improve the breeding value of the original (S0 parental material and sharply accelerate genetic gains. For instance, homozygous S1 genotypes for the dominant resistance to cassava mosaic disease could be generated and selected. All gametes from these selected S1 genotypes would carry the desirable allele

An extraction method of uranium 233 from the thorium irradiates in a reactor core

International Nuclear Information System (INIS)

Chesne, A.; Regnaut, P.

1955-01-01

Description of the conditions of separation of the thorium, of the uranium 233 and of the protactinium 233 in hydrochloric solution by absorption then selective elution on anion exchange resin. A precipitation of the thorium by the oxalic acid permits the recuperation of the hydrochloric acid which is recycled, the main, raw material consumed being the oxalic acid. (authors) [fr

Detección del virus de la leucosis bovina en ganado criollo colombiano mediante PCR-anidado Bovine leukemia virus detection in Creole Colombian breeds using nested-PCR

Directory of Open Access Journals (Sweden)

Darwin Yovanny Hernández-Herrera

2011-12-01

Full Text Available Se evaluó la presencia del virus de la leucosis bovina (VLB en 360 muestras de ADN de ocho razas bovinas criollas: Blanco Orejinegro (BON, Casanareño (CAS, Costeño con Cuernos (CCC, Chino Santandereano (ChS, Caqueteño (CQT, Hartón del Valle (HV, Romosinuano (RS y San Martinero (SM, dos Razas Sintéticas Colombianas: Lucerna (LUC y Velásquez (VEL y dos razas foráneas: Brahmán (B y Holstein (H. Para la detección del pro-virus se amplificó una región del gen env viral, mediante PCR anidada. La presencia del VLB fue mayor en la raza HV seguido por ChS (83.3% y 60% respectivamente, VEL y LUC tuvieron el mismo porcentaje (50%, en CAS, CCC y CQT la presencia del virus fue de 26.7%, 23.3% y 16.7% respectivamente; no se encontró el virus en BON, SM y RS. En las razas foráneas la presencia fue de 83.3% para H y 6.7% para B. Se encontró dependencia altamente significativa entre la presencia del VLB y la raza, el sexo y región de origen de la muestra. El promedio de presencia en las razas criollas fue menor que en las foráneas, menor en los machos que en las hembras y en la región norte que en el suroccidente y el centro del país.Using 360 DNA samples from eight Creole bovine breeds Blanco Orejinegro (BON, Casanareño (CAS, Costeño con Cuernos (CCC, Chino Santandereano (ChS, Caqueteño (CQT, Hartón del Valle (HV, Romosinuano (RS and San Martinero (SM, two synthetic Colombian breeds: Lucerna (LUC and Velásquez (VEL and two introduced breeds Brahmán (B and Holstein (H; the presence of Bovine Leukemia Virus (BLV was evaluated through the amplification of a viral gene region env (provirus detection - nested-PCR. The percentage of presence and independence test were calculated (X². Presence of BLV was higher in HV breed, followed by ChS (83.3% and 60% respectively; VEL and LUC breeds showed the same percentage (50%. In CAS, CCC and CQT the presence of virus was 26.7%, 23.3% y 16.7% respectively. On the other hand, no virus presence was

Ornamental Plant Breeding

Directory of Open Access Journals (Sweden)

Flávia Barbosa Silva Botelho

2015-04-01

Full Text Available World’s ornamental plant market, including domestic market of several countries and its exports, is currently evaluated in 107 billion dollars yearly. Such estimate highlights the importance of the sector in the economy of the countries, as well as its important social role, as it represents one of the main activities, which contributes to income and employment. Therefore a well-structured plant breeding program, which is connected with consumers’ demands, is required in order to fulfill these market needs globally. Activities related to pre-breeding, conventional breeding, and breeding by biotechnological techniques constitute the basis for the successful development of new ornamental plant cultivars. Techniques that involve tissue culture, protoplast fusion and genetic engineering greatly aid conventional breeding (germplasm introduction, plant selection and hybridization, aiming the obtention of superior genotypes. Therefore it makes evident, in the literature, the successful employment of genetic breeding, since it aims to develop plants with commercial value that are also competitive with the ones available in the market.

33 CFR 110.233 - Prince William Sound, Alaska.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Prince William Sound, Alaska. 110... ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.233 Prince William Sound, Alaska. (a) The anchorage grounds. In Prince William Sound, Alaska, beginning at a point at latitude 60°40′00″ N., longitude 146°40...

Copycats in Pilot Aircraft-Assisted Suicides after the Germanwings Incident

Directory of Open Access Journals (Sweden)

Tanja Laukkala

2018-03-01

Full Text Available Aircraft-assisted pilot suicide is a rare but serious phenomenon. The aim of this study was to evaluate changes in pilot aircraft-assisted suicide risks, i.e., a copycat effect, in the U.S. and Germany after the Germanwings 2015 incident in the French Alps. Aircraft-assisted pilot suicides were searched in the U.S. National Transportation Safety Board (NTSB accident investigation database and in the German Bundestelle für Flugunfalluntersuchung (BFU Reports of Investigation database five years before and two years after the deliberate crash of the Germanwings flight into the French Alps in 2015. The relative risk (RR of the aircraft-assisted pilot suicides was calculated. Two years after the incident, three out of 454 (0.66% fatal incidents were aircraft-assisted suicides compared with six out of 1292 (0.46% in the prior five years in the NTSB database. There were no aircraft-assisted pilot suicides in the German database during the two years after or five years prior to the Germanwings crash. The relative aircraft-assisted pilot suicide risk for the U.S. was 1.4 (95% CI 0.3–4.2 which was not statistically significant. Six of the pilots who died by suicide had told someone of their suicidal intentions. We consider changes in the rate to be within a normal variation. Responsible media coverage of aircraft incidents is important due to the large amount of publicity that these events attract.

Copycats in Pilot Aircraft-Assisted Suicides after the Germanwings Incident

Science.gov (United States)

Vuorio, Alpo; Bor, Robert; Budowle, Bruce; Navathe, Pooshan; Pukkala, Eero; Sajantila, Antti

2018-01-01

Aircraft-assisted pilot suicide is a rare but serious phenomenon. The aim of this study was to evaluate changes in pilot aircraft-assisted suicide risks, i.e., a copycat effect, in the U.S. and Germany after the Germanwings 2015 incident in the French Alps. Aircraft-assisted pilot suicides were searched in the U.S. National Transportation Safety Board (NTSB) accident investigation database and in the German Bundestelle für Flugunfalluntersuchung (BFU) Reports of Investigation database five years before and two years after the deliberate crash of the Germanwings flight into the French Alps in 2015. The relative risk (RR) of the aircraft-assisted pilot suicides was calculated. Two years after the incident, three out of 454 (0.66%) fatal incidents were aircraft-assisted suicides compared with six out of 1292 (0.46%) in the prior five years in the NTSB database. There were no aircraft-assisted pilot suicides in the German database during the two years after or five years prior to the Germanwings crash. The relative aircraft-assisted pilot suicide risk for the U.S. was 1.4 (95% CI 0.3–4.2) which was not statistically significant. Six of the pilots who died by suicide had told someone of their suicidal intentions. We consider changes in the rate to be within a normal variation. Responsible media coverage of aircraft incidents is important due to the large amount of publicity that these events attract. PMID:29534475

Breeding bird populations and habitat associations within the Savannah River Site (SRS).

Energy Technology Data Exchange (ETDEWEB)

Gauthreaux, Sidney, A.; Steven J. Wagner.

2005-06-29

Gauthreaux, Sidney, A., and Steven J. Wagner. 2005. Breeding bird populations and habitat associations within the Savannah River Site (SRS). Final Report. USDA Forest Service, Savannah River, Aiken, SC. 48 pp. Abstract: During the 1970's and 1980's a dramatic decline occurred in the populations of Neotropical migratory birds, species that breed in North America and winter south of the border in Central and South America and in the Caribbean. In 1991 an international initiative was mounted by U. S. governmental land management agencies, nongovernmental conservation agencies, and the academic and lay ornithological communities to understand the decline of Neotropical migratory birds in the Americas. In cooperation with the USDA Forest Service - Savannah River (FS - SR) we began 1992 a project directed to monitoring population densities of breeding birds using the Breeding Bird Census (BBC) methodology in selected habitats within the Savannah River Site SRS. In addition we related point count data on the occurrence of breeding Neotropical migrants and other bird species to the habitat data gathered by the Forest Inventory and Analysis (FIA) program of the USDA Forest Service and data on habitat treatments within forest stands.

Pilot study for natural radiation survey

International Nuclear Information System (INIS)

Brown, L.; Driscoll, C.M.H.; Green, B.M.R.; Miles, J.C.H.

1983-01-01

NRPB's national survey of natural radiation exposure in homes commenced in 1982 and will run until 1984. A pilot survey was undertaken in over 100 homes for one year, using passive thermoluminescent dosemeters to measure external radiation from terrestrial and cosmic sources and passive radon dosemeters to measure the radon-222 gas concentration. A preliminary analysis of the results obtained from the pilot survey is given. The main value of the pilot survey was in providing experience and various administrative and scientific procedures have been simplified or automated for the national survey. (U.K.)

A simple language to script and simulate breeding schemes: the breeding scheme language

Science.gov (United States)

It is difficult for plant breeders to determine an optimal breeding strategy given that the problem involves many factors, such as target trait genetic architecture and breeding resource availability. There are many possible breeding schemes for each breeding program. Although simulation study may b...

To breed or not to breed: a seabird's response to extreme climatic events

OpenAIRE

Cubaynes, Sarah; Doherty, Paul F.; Schreiber, E. A.; Gimenez, Olivier

2010-01-01

Intermittent breeding is an important life-history strategy that has rarely been quantified in the wild and for which drivers remain unclear. It may be the result of a trade-off between survival and reproduction, with individuals skipping breeding when breeding conditions are below a certain threshold. Heterogeneity in individual quality can also lead to heterogeneity in intermittent breeding. We modelled survival, recruitment and breeding probability of the red-footed booby (Sula sula), usin...

Pilot Certification, Age of Pilot, and Drug Use in Fatal Civil Aviation Accidents.

Science.gov (United States)

Akparibo, Issaka Y; Stolfi, Adrienne

2017-10-01

This study examined the association between mean age of pilot, pilot license, pilot medical certificate and drug use trends in pilots fatally injured in aircraft accidents. The prevalence of prescription drugs, OTC drugs, controlled drugs and drugs that may be potentially impairing was also examined. This study was a descriptive observational study in which the NTSB Aviation Accident Database was searched from the period beginning January 1, 2012 to December 31, 2014. During the study period a total of 706 accidents involving 711 fatalities were investigated by the NTSB. This study included 633 of these accidents, involving 646 fatalities. Of these pilots, 42.1% had drugs in their biological samples. The prevalence of prescription drugs, controlled drugs, OTC drugs, opioids, and potentially impairing drugs in the fatally injured pilot population over the study period was 28.9%, 15.0%, 20.1%, 5.1%, and 25.5%, respectively. Pilots with any drugs in their samples were significantly older than those without drugs. Medical certificate held was associated with drug use; pilots who held third class certificates had the highest prevalence at 54.1%. Pilot license was not associated with drug use. In 3.8% of the accidents, drugs were a contributing factor in the cause. Despite current FAA medical regulations, potentially impairing drugs are frequently found in biological samples of fatally injured pilots in the U.S. More education of airmen by aviation medical examiners is needed on the safety of drug use.Akparibo IY, Stolfi A. Pilot certification, age of pilot, and drug use in fatal civil aviation accidents. Aerosp Med Hum Perform. 2017; 88(10):931-936.

75 FR 59686 - Proposed Information Collection; Comment Request; Coast Pilot Report

Science.gov (United States)

2010-09-28

... Collection; Comment Request; Coast Pilot Report AGENCY: National Oceanic and Atmospheric Administration (NOAA.... 165, or coast.pilot@noaa.gov . SUPPLEMENTARY INFORMATION: I. Abstract NOAA publishes the United States (U.S.) Coast Pilot, a series of nine books which supplement the suite of nautical charts published by...

Tritium breeding blanket

International Nuclear Information System (INIS)

Smith, D.; Billone, M.; Gohar, Y.; Baker, C.; Mori, S.; Kuroda, T.; Maki, K.; Takatsu, H.; Yoshida, H.; Raffray, A.; Sviatoslavsky, I.; Simbolotti, G.; Shatalov, G.

1991-01-01

The terms of reference for ITER provide for incorporation of a tritium breeding blanket with a breeding ratio as close to unity as practical. A breeding blanket is required to assure an adequate supply of tritium to meet the program objectives. Based on specified design criteria, a ceramic breeder concept with water coolant and an austenitic steel structure has been selected as the first option and lithium-lead blanket concept has been chosen as an alternate option. The first wall, blanket, and shield are integrated into a single unit with separate cooling systems. The design makes extensive use of beryllium to enhance the tritium breeding ratio. The design goals with a tritium breeding ratio of 0.8--0.9 have been achieved and the R ampersand D requirements to qualify the design have been identified. 4 refs., 8 figs., 2 tabs

White Matter Hyperintensities on MRI in High-Altitude U-2 Pilots

Science.gov (United States)

2013-08-19

SUBJECT TERMS MRI; white matter hyperintensities; hypobaric exposure; neurological decompression sickness 16. SECURITY CLASSIFICATION OF: 17...normal controls and did not increase with age in pilots, suggesting that hypobaric exposure produces white matter damage different from that occurring in...relapse we observed in 3 NDCS pilots after successful hyperbaric treatment (US Navy Treatment Table 6; 100% fraction of inspired oxygen; 2.8 atm absolute

Numerical simulations of groundwater flow and solute transport in the Lake 233 aquifer

Energy Technology Data Exchange (ETDEWEB)

Klukas, M H; Moltyaner, G L

1995-05-01

A three-dimensional numerical flow model of the Lake 233 aquifer underlying the site of the proposed Intrusion Resistant Underground Structure (IRUS) for low level waste disposal is developed. A reference hydraulic conductivity distribution incorporating the key stratigraphic units and field estimates of recharge from Lake 233 are used as model input. The model was calibrated against the measured hydraulic head distribution, the flowpath of a historic {sup 90}Sr plume in the aquifer and measured groundwater velocities. (author). 23 refs., 4 tabs., 31 figs.

Numerical simulations of groundwater flow and solute transport in the Lake 233 aquifer

International Nuclear Information System (INIS)

Klukas, M.H.; Moltyaner, G.L.

1995-05-01

A three-dimensional numerical flow model of the Lake 233 aquifer underlying the site of the proposed Intrusion Resistant Underground Structure (IRUS) for low level waste disposal is developed. A reference hydraulic conductivity distribution incorporating the key stratigraphic units and field estimates of recharge from Lake 233 are used as model input. The model was calibrated against the measured hydraulic head distribution, the flowpath of a historic 90 Sr plume in the aquifer and measured groundwater velocities. (author). 23 refs., 4 tabs., 31 figs

Nuclear symbiosis. Why, when and how

International Nuclear Information System (INIS)

Stewart, H.B.

1978-01-01

A distinction can be made between an ''asymptotic'' nuclear symbiosis and a ''transitional'' nuclear symbiosis. With the currently projected nuclear energy growth, there appears to be no urgency for introducing nuclear systems required for the asymptotic era before, say, another 50 to 75 years. Consequently, more attention should be directed toward desirable systems for the transitional era, i.e., the next 30 to 50 years. In the classical asymptotic system, an optimal system would consist of a relatively small number of fast breeder reactor plants operating largely as ''fuel factories'' and a large number of thermal spectrum near breeder reactor plants serving as ''energy factories''. The breeding ratio of 238 U/Pu in the FBR plants would be chosen at unity to assure that FBR primary fuel could sustain itself. Excess breeding capacity would be utilized to convert 232 Th and 233 U in the blankets. This excess fuel would then be used to supply make-up requirements for thermal near breeder (NBR) plants. With an FBR breeder ratio of 1.4 and an NBR conversion ratio of 0.9, approximately four NBR plants could be supported for each FBR plant. Perhaps more importantly, the sale of 233 U to the NBR could be used to offset a probable higher capital cost of the FBR plants. In this way, a capital cost penalty of some 30 to 40% relative to LWR plants might be allowable for FBR plants. (author)

Reproduction Efficiency and Health Traits in Dorper, White Dorper, and Tsigai Sheep Breeds under Temperate European Conditions

Directory of Open Access Journals (Sweden)

D. Gavojdian

2015-04-01

Full Text Available The objective of the current pilot study was to evaluate the reproductive performance and health indicators in Dorper, White Dorper, and Tsigai breed ewes managed semi-intensively under European temperate conditions. A total of 544 ewe-year units were observed, with ewes (ranging from 1.5 to 8 years of age managed under identical rearing conditions for a period of two consecutive production cycles (2012 through 2013 and 2013 through 2014. In general, significant (p≤0.001 genotype-related disparities were found in occurrence rates for all health parameters taken into study. Clinical mastitis incidence was significantly lower (p≤0.05 in Dorper (9.4% and White Dorper (10.8% breeds compared to that of Tsigai ewes (17.4%. Significant differences (p≤0.05 for lameness were found between Dorper and Tsigai breeds, with occurrence rates of 8.0% and 2.9%, respectively. Incidence for pneumonia and abortion was not influenced (p>0.05 by the ewes’ genotype. Litter size was significantly lower (p≤0.05 in White Dorper breed than for Dorper and Tsigai ewes, of 1.21, 1.40, and 1.45, respectively. Conception rates and lambs survival were not affected (p>0.05 by genotype. Results suggest that South African Dorper and White Dorper sheep breeds have adapted well to the specific rearing conditions.

Symbiosis of near breeder HTR's with hybrid fusion reactors

International Nuclear Information System (INIS)

Seifritz, W.

1978-07-01

In this contribution to INFCE a symbiotic fusion/fission reactor system, consisting of a hybrid beam-driven micro-explosion fusion reactor (HMER) and associated high-temperature gas-cooled reactors (HTR) with a coupled fuel cycle, is proposed. This system is similar to the well known Fast Breeder/Near Breeder HTR symbiosis except that the fast fission breeder - running on the U/Pu-cycle in the core and the axial blankets and breeding the surplus fissile material as U-233 in its radial thorium metal or thorium oxide blankets - is replaced by a hybrid micro-explosion DT fusion reactor

Textbook animal breeding : animal breeding andgenetics for BSc students

NARCIS (Netherlands)

Oldenbroek, Kor; Waaij, van der Liesbeth

2014-01-01

This textbook contains teaching material on animal breeding and genetics for BSc students. The text book started as an initiative of the Dutch Universities for Applied (Agricultural) Sciences. The textbook is made available by the Animal Breeding and Genomics Centre (ABGC) of Wageningen UR

Tritium breeding in fusion reactors

International Nuclear Information System (INIS)

Abdou, M.A.

1982-10-01

Key technological problems that influence tritium breeding in fusion blankets are reviewed. The breeding potential of candidate materials is evaluated and compared to the tritium breeding requirements. The sensitivity of tritium breeding to design and nuclear data parameters is reviewed. A framework for an integrated approach to improve tritium breeding prediction is discussed with emphasis on nuclear data requirements

45 CFR 233.101 - Dependent children of unemployed parents.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 2 2010-10-01 2010-10-01 false Dependent children of unemployed parents. 233.101... unemployed parents. (a) Requirements for State Plans. Effective October 1, 1990 (for Puerto Rico, American... children of unemployed parents. A State plan under title IV-A for payment of such aid must: (1) Include a...

Reaction rate constants of HO2 + O3 in the temperature range 233-400 K

Science.gov (United States)

Wang, Xiuyan; Suto, Masako; Lee, L. C.

1988-01-01

The reaction rate constants of HO2 + O3 were measured in the temperature range 233-400 K using a discharge flow system with photofragment emission detection. In the range 233-253 K, the constants are approximately a constant value, and then increase with increasing temperature. This result suggests that the reaction may have two different channels. An expression representing the reaction rate constants is presented.

US Daily Pilot Balloon Observations

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Pilot Balloon observational forms for the United States. Taken by Weather Bureau and U.S. Army observers. Period of record 1918-1960. Records scanned from the NCDC...

45 CFR 233.100 - Dependent children of unemployed parents.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 2 2010-10-01 2010-10-01 false Dependent children of unemployed parents. 233.100... unemployed parents. (a) Requirements for State Plans. If a State wishes to provide AFDC for children of unemployed parents, the State plan under title IV-A of the Social Security Act must: (1) Include a definition...

To breed or not to breed: a seabird's response to extreme climatic events.

Science.gov (United States)

Cubaynes, Sarah; Doherty, Paul F; Schreiber, E A; Gimenez, Olivier

2011-04-23

Intermittent breeding is an important life-history strategy that has rarely been quantified in the wild and for which drivers remain unclear. It may be the result of a trade-off between survival and reproduction, with individuals skipping breeding when breeding conditions are below a certain threshold. Heterogeneity in individual quality can also lead to heterogeneity in intermittent breeding. We modelled survival, recruitment and breeding probability of the red-footed booby (Sula sula), using a 19 year mark-recapture dataset involving more than 11,000 birds. We showed that skipping breeding was more likely in El-Niño years, correlated with an increase in the local sea surface temperature, supporting the hypothesis that it may be partly an adaptive strategy of birds to face the trade-off between survival and reproduction owing to environmental constraints. We also showed that the age-specific probability of first breeding attempt was synchronized among different age-classes and higher in El-Niño years. This result suggested that pre-breeders may benefit from lowered competition with experienced breeders in years of high skipping probabilities.

Costs Associated with Equine Breeding in Kentucky

Science.gov (United States)

Walker, Cassandra L.

There were approximately 9 million horses in the United States having a 102 billion impact on the U.S. economy (AHC, 2005). Over 1 million of those horses were involved in the breeding sector. In Kentucky, nearly 18% of the horse population have been involved in breeding. Managing an equine enterprise can be difficult, particularly given that many who undertake such endeavors do not have a background or education in business management. Kentucky Cooperative Extension has produced interactive spreadsheets to help horse owners better understand the costs associated with owning horses or managing certain equine businesses, including boarding and training operations. However, there has been little support for breeders. Therefore, the objectives of this study were to provide owners with a list of services offered for breeding and the costs associated with those services. Survey questions were created from a list of topics pertinent to equine breeding and from that list of questions, an electronic survey was created. The survey was sent via Qualtrics Survey Software to collect information on stallion and mare management costs as well as expenses related to owning and breeding. Question topics included veterinary and housing costs, management and advertising expenses, and membership fees. A total of 78 farms were selected from the 2013 breeder's listings for the Kentucky Quarter Horse Association (n = 39) and the Kentucky Thoroughbred Farm Managers' Club (n = 26), and other breed association contacts (n = 13). These farms were selected from the lists by outside individuals who were not related to the project. Participants were asked to answer all questions relevant to the farm. After the initial survey distribution, follow-up e-mails and phone calls were conducted in order to answer any questions participants might have had about the survey. Survey response rate was 32.1% (25 of 78 surveys returned). Farms in Kentucky had an average of two farm-owned and two outside

77 FR 11515 - Application To Export Electric Energy; Pilot Power Group, Inc.

Science.gov (United States)

2012-02-27

... reliability of the U.S. electric power supply system. Copies of this application will be made available, upon... DEPARTMENT OF ENERGY [OE Docket No. EA-383] Application To Export Electric Energy; Pilot Power... application. SUMMARY: Pilot Power Group, Inc. (Pilot Power) has applied for authority to transmit electric...

75 FR 28554 - Elimination of Classification Requirement in the Green Technology Pilot Program

Science.gov (United States)

2010-05-21

...] Elimination of Classification Requirement in the Green Technology Pilot Program AGENCY: United States Patent... (USPTO) implemented the Green Technology Pilot Program on December 8, 2009, which permits patent... technologies. However, the pilot program was limited to only applications classified in a number of U.S...

75 FR 70061 - Dealer Floor Plan Pilot Program Meeting

Science.gov (United States)

2010-11-16

... SMALL BUSINESS ADMINISTRATION Dealer Floor Plan Pilot Program Meeting AGENCY: U.S. Small Business... location, date, time, and agenda for a meeting regarding the Dealer Floor Plan Pilot Program established in the Small Business Jobs Act of 2010. The meeting will be open to the public. DATES: The Dealer Floor...

Evaluation of the Inhalation Toxicology Research Institute beagle dog closed breeding colony: a progress report

International Nuclear Information System (INIS)

Lustgarten, C.S.; Hobbs, C.H.; Muggenburg, B.A.; Benjamin, S.A.; Slauson, D.O.; Hahn, F.F.

1974-01-01

Since early 1968, a closed breeding colony has been in operation at the Inhalation Toxicology Research Institute to produce experimental dogs for inhalation toxicology studies and to replace colony breeding stock for producing dogs with a stable gene pool. From March 1, 1968 through July 15, 1974, 123 bitches were bred 613 times, resulting in 540 litters and 2809 puppies: a conception rate for this period of 88.9 percent. An average of 3.74 pups survived to one year of age. (U.S.)

Colorimetric on-line control of U

International Nuclear Information System (INIS)

Perez, J.J.; Boisde, G.; Dedaldechamp, P.; Dureault, B.

The instrumentation developed for the automatic colorimetric control of U is presented. Two techniques are used: absorptiometry of U ions using optical probes enabling to measure in situ the solutions containing 0.5 g U(IV)/l or 1 g U(VI)/l; colorimetry of the U-DBM complexe after separation of U by TOPO (this technique is applied to the control of U at the ppm level). The automatic devices used are described. They are experimented in laboratory or in pilot-plant [fr

Analysis of breed effects on semen traits in light horse, warmblood, and draught horse breeds.

Science.gov (United States)

Gottschalk, Maren; Sieme, Harald; Martinsson, Gunilla; Distl, Ottmar

2016-05-01

In the present study, systematic effects on semen quality traits were investigated in 381 stallions representing 22 breeds. All stallions were used for AI either at the Lower Saxon National Stud Celle or the North Rhine-Westphalian National Stud Warendorf. A total of 71,078 fresh semen reports of the years 2001 to 2014 were edited for analysis of gel-free volume, sperm concentration, total number of sperm, progressive motility, and total number of progressively motile sperm. Breed differences were studied for warmblood and light horse breeds of both national studs (model I) and for warmblood breeds and the draught horse breed Rhenish German Coldblood from the North Rhine-Westphalian National stud (model II) using mixed model procedures. The fixed effects of age class, year, and month of semen collection had significant influences on all semen traits in both analyses. A significant influence of the horse breed was found for all semen traits but gel-free volume in both statistical models. Comparing warmblood and light horse stallions of both national studs, we observed highest sperm concentrations, total numbers of sperm, and total numbers of progressively motile sperm in Anglo-Arabian stallions. The draught horse breed Rhenish German Coldblood had the highest least squares means for gel-free volume, whereas all other investigated semen traits were significantly lower in this breed compared to the warmblood stallions under study. The variance components among stallions within breeds were significant for all semen traits and accounted for 40% to 59% of the total variance. The between-breed-variance among stallions was not significant underlining the similar size of the random stallion effect in each of the horse breeds analyzed here. In conclusion, breed and stallion are accounting for a significant proportion of the variation in semen quality. Copyright © 2016 Elsevier Inc. All rights reserved.

ALARA review for the decontamination and decommissioning of the 233-S pipe trench

International Nuclear Information System (INIS)

Kornish, M.J.

1998-01-01

The 233-S Facility was completed in 1955 to expand plutonium production by further concentrating the plutonium nitrate product solution from the Reduction Oxidation (REDOX) Plant. The facility is radiologically contaminated because of operations and accidents. Isolation from REDOX and removal of the product transfer lines from the pipe trench is the second step in the decontamination and decommissioning of the entire 233-S Facility. The work scope is to isolate all piping from REDOX and then to remove all the piping/equipment from the pipe trench. The building is presently a Hazard Category 2 Nuclear Facility. A formal as low as reasonably achievable (ALARA) review is required by BHI-SH-02, Vol. 1, Procedure No. 1.22, Planning Radiological Work, when radiological conditions exceed trigger levels. The level of contamination inside the pipe trench and the process fluid piping is unknown. The potential exists to exceed the level of loose surface contamination, which requires a formal ALARA review when opening the pipe trench and cutting of piping commences. This ALARA review is for task instruction 1997-03-18-009 Revision 1, 233-S Pipe Trench Decon and Pipe Removal

Breeding performance in the Italian chicken breed Mericanel della Brianza

Directory of Open Access Journals (Sweden)

Stefano P. Marelli

2010-11-01

Full Text Available In Italy, 90 local avian breeds were described, the majority (61% were classified extinct and only 8.9 % still diffused. Therefore, efforts for conservation of Italian avian breeds are urgently required. The aim of this study was to record the breeding performance of the Italian breed Mericanel della Brianza and multiply a small population, in order to develop a conservation program. Fourteen females and 8 males were available at the beginning of the reproductive season in 2009 and organized in 8 families (1 male/1-2 females kept in floor pens. Birds received a photoperiod of 14L:10D and fed ad libitum. Breeding performance was recorded from March to June. Egg production and egg weight were recorded daily; eggs were set every 2 weeks and fertility, embryo mortality and hatchability were recorded. Mean egg production was 37% and mean egg weight was 34±3.49 g. High fertility values were recorded in the first three settings, from 94 to 87%, and the overall mean fertility value was 81.6%. Overall hatchability was only 49.6% due to a high proportion of dead embryos. Embryo mortality occurred mainly between day 2 and 7 of incubation and during hatch. Highest hatchability values were recorded in setting 1 and 2, 69 and 60% respectively, and a great decrease was found in the following settings. Great variations in egg production, fertility, hatchability and embryo mortality were found among families. The present results are the basic knowledge on reproductive parameters necessary to improve the reproductive efficiency of the breed within a conservation plan.

The Arg233Lys AQP0 mutation disturbs aquaporin0-calmodulin interaction causing polymorphic congenital cataract.

Directory of Open Access Journals (Sweden)

Shanshan Hu

Full Text Available Calmodulin (CaM directly interacts with the aquaporin 0 (AQP0 C-terminus in a calcium dependent manner to regulate the water permeability of AQP0. We previously identified a missense mutation (p.R233K in the putative CaM binding domain of AQP0 C-terminus in a congenital cataract family. This study was aimed at exploring the potential pathogenesis of this mutation causative of cataract and mainly identifying how it influenced the binding of AQP0 to CaM. Wild type and R233K mutant AQP0 with EGFP-tag were transfected separately into Hela cells to determine the expression and subcellular localizations. The co-immunoprecipitation (CoIP assay was used to detect the interaction between AQP0 and CaM. AQP0 C-terminus peptides were synthesized with and without R233K, and the binding abilities of these peptides to CaM were assessed using a fluorescence binding assay. Localizations of wild type and R233K mutant AQP0 were determined from EGFP fluorescence, and the chimeric proteins were both localized abundantly in the plasma membrane. Protein expression levels of the culture cells showed no significant difference between them. The results from CoIP assay implied that R233K mutant presented more weakly in association with CaM than wild type AQP0. The AQP0 C-terminal mutant peptide was found to have 2.5-fold lower binding affinity to CaM than wild type peptide. These results suggested that R233K mutation did not affect the expression, location and trafficking of the protein but did influence the interaction between AQP0 and CaM. The binding affinity of AQP0 C-terminus to CaM was significantly reduced. Due to lack of the modulation of the Ca2+-calmodulin complex, the water permeability of AQP0 was subsequently augmented, which might lead to the development of this cataract.

NSTAR Smart Grid Pilot

Energy Technology Data Exchange (ETDEWEB)

Rabari, Anil [NSTAR Electric, Manchester, NH (United States); Fadipe, Oloruntomi [NSTAR Electric, Manchester, NH (United States)

2014-03-31

NSTAR Electric & Gas Corporation (“the Company”, or “NSTAR”) developed and implemented a Smart Grid pilot program beginning in 2010 to demonstrate the viability of leveraging existing automated meter reading (“AMR”) deployments to provide much of the Smart Grid functionality of advanced metering infrastructure (“AMI”), but without the large capital investment that AMI rollouts typically entail. In particular, a central objective of the Smart Energy Pilot was to enable residential dynamic pricing (time-of-use “TOU” and critical peak rates and rebates) and two-way direct load control (“DLC”) by continually capturing AMR meter data transmissions and communicating through customer-sited broadband connections in conjunction with a standardsbased home area network (“HAN”). The pilot was supported by the U.S. Department of Energy’s (“DOE”) through the Smart Grid Demonstration program. NSTAR was very pleased to not only receive the funding support from DOE, but the guidance and support of the DOE throughout the pilot. NSTAR is also pleased to report to the DOE that it was able to execute and deliver a successful pilot on time and on budget. NSTAR looks for future opportunities to work with the DOE and others in future smart grid projects.

A method for the quantitative determination of uranium-233 in an irradiated thorium rod; Une methode de dosage de l'uranium 233 contenu dans un barreau de thorium irradie

Energy Technology Data Exchange (ETDEWEB)

Bathellier, A; Sontag, R; Chesne, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1961-07-01

A rapid method for the quantitative determination of uranium-233 in irradiated thorium is described. A 30 per cent solution of trilaurylamine in xylene is used to extract the uranium from an aqueous hydrochloric acid solution and separate it from the thorium. This may be followed by {alpha} counting or fluorimetry. The practical operating conditions of the separation are discussed in detail. (author) [French] Une methode rapide de dosage de l'uranium-233 contenu dans le thorium irradie est decrite. Elle utilise la trilauryfamine a 30 pour cent dans le xylene pour extraire l'uranium d'une dissolution aqueuse chlorhydrique et le separer du thorium. Le comptage {alpha} ou la fluorimetrie sont alors possibles. Les conditions operatoires de la separation sont discutees et precisees. (auteur)

Population size, breeding biology and on-land threats of Cape Verde petrel (Pterodroma feae) in Fogo Island, Cape Verde.

Science.gov (United States)

Militão, Teresa; Dinis, Herculano Andrade; Zango, Laura; Calabuig, Pascual; Stefan, Laura M; González-Solís, Jacob

2017-01-01

Cape Verde petrel (Pterodroma feae) is currently considered near threatened, but little is known about its population size, breeding biology and on land threats, jeopardizing its management and conservation. To improve this situation, we captured, marked and recaptured (CMR) birds using mist-nets over 10 years; measured and sexed them; monitored up to 14 burrows, deployed GPS devices on breeders and analyzed activity data of geolocators retrieved from breeders in Fogo (Cape Verde). We set cat traps over the colony and investigated their domestic/feral origin by marking domestic cats from a nearby village with transponders, by deploying GPS devices on domestic cats and by performing stable isotope analyses of fur of the trapped and domestic cats. The population of Fogo was estimated to be 293 birds, including immatures (95% CI: 233-254, CMR modelling). Based on geolocator activity data and nest monitoring we determined the breeding phenology of this species and we found biometric differences between sexes. While monitoring breeding performance, we verified a still ongoing cat predation and human harvesting. Overall, data gathered from trapped cats without transponder, cats GPS trips and the distinct isotopic values between domestic and trapped cats suggest cats visiting the colony are of feral origin. GPS tracks from breeders showed birds left and returned to the colony using the sector NE of the islands, where high level of public lights should be avoided specially during the fledging period. Main threats for the Cape Verde petrel in the remaining breeding islands are currently unknown but likely to be similar to Fogo, calling for an urgent assessment of population trends and the control of main threats in all Cape Verde Islands and uplisting its conservation status.

Population size, breeding biology and on-land threats of Cape Verde petrel (Pterodroma feae in Fogo Island, Cape Verde.

Directory of Open Access Journals (Sweden)

Teresa Militão

Full Text Available Cape Verde petrel (Pterodroma feae is currently considered near threatened, but little is known about its population size, breeding biology and on land threats, jeopardizing its management and conservation. To improve this situation, we captured, marked and recaptured (CMR birds using mist-nets over 10 years; measured and sexed them; monitored up to 14 burrows, deployed GPS devices on breeders and analyzed activity data of geolocators retrieved from breeders in Fogo (Cape Verde. We set cat traps over the colony and investigated their domestic/feral origin by marking domestic cats from a nearby village with transponders, by deploying GPS devices on domestic cats and by performing stable isotope analyses of fur of the trapped and domestic cats. The population of Fogo was estimated to be 293 birds, including immatures (95% CI: 233-254, CMR modelling. Based on geolocator activity data and nest monitoring we determined the breeding phenology of this species and we found biometric differences between sexes. While monitoring breeding performance, we verified a still ongoing cat predation and human harvesting. Overall, data gathered from trapped cats without transponder, cats GPS trips and the distinct isotopic values between domestic and trapped cats suggest cats visiting the colony are of feral origin. GPS tracks from breeders showed birds left and returned to the colony using the sector NE of the islands, where high level of public lights should be avoided specially during the fledging period. Main threats for the Cape Verde petrel in the remaining breeding islands are currently unknown but likely to be similar to Fogo, calling for an urgent assessment of population trends and the control of main threats in all Cape Verde Islands and uplisting its conservation status.

A Pilot Study to Test the Efficacy of Psychologically Based Physical Therapy Training for Treating Deployed U.S. Sailors and Marines with Musculoskeletal Injuries

Science.gov (United States)

2017-10-01

Department of Population Health , NYU Langone Medical Center, New York, NY. ****Department of Physical Therapy, Naval Medical Center Portsmouth...AWARD NUMBER: W81XWH-14-2-0146 TITLE: A Pilot Study to Test the Efficacy of Psychologically Based Physical Therapy Training for Treating...Test the Efficacy of Psychologically Based Physical Therapy Training for Treating Deployed U.S. Sailors and Marines with Musculoskeletal Injuries 5b

What drives cooperative breeding?

Directory of Open Access Journals (Sweden)

Walter D Koenig

2017-06-01

Full Text Available Cooperative breeding, in which more than a pair of conspecifics cooperate to raise young at a single nest or brood, is widespread among vertebrates but highly variable in its geographic distribution. Particularly vexing has been identifying the ecological correlates of this phenomenon, which has been suggested to be favored in populations inhabiting both relatively stable, productive environments and in populations living under highly variable and unpredictable conditions. Griesser et al. provide a novel approach to this problem, performing a phylogenetic analysis indicating that family living is an intermediate step between nonsocial and cooperative breeding birds. They then examine the ecological and climatic conditions associated with these different social systems, concluding that cooperative breeding emerges when family living is favored in highly productive environments, followed secondarily by selection for cooperative breeding when environmental conditions deteriorate and within-year variability increases. Combined with recent work addressing the fitness consequences of cooperative breeding, Griesser et al.'s contribution stands to move the field forward by demonstrating that the evolution of complex adaptations such as cooperative breeding may only be understood when each of the steps leading to it are identified and carefully integrated.

indigenous cattle breeds

African Journals Online (AJOL)

Received 31 August 1996; accepted 20 March /998. Mitochondrial DNA cleavage patterns from representative animals of the Afrikaner and Nguni sanga cattle breeds, indigenous to Southern Africa, were compared to the mitochondrial DNA cleavage patterns of the Brahman (zebu) and the Jersey. (taurine) cattle breeds.

Genomic dairy cattle breeding

DEFF Research Database (Denmark)

Mark, Thomas; Sandøe, Peter

2010-01-01

the thoughts of breeders and other stakeholders on how to best make use of genomic breeding in the future. Intensive breeding has played a major role in securing dramatic increases in milk yield since the Second World War. Until recently, the main focus in dairy cattle breeding was on production traits...... it less accountable to the concern of private farmers for the welfare of their animals. It is argued that there is a need to mobilise a wide range of stakeholders to monitor developments and maintain pressure on breeding companies so that they are aware of the need to take precautionary measures to avoid...

Across Breed QTL Detection and Genomic Prediction in French and Danish Dairy Cattle Breeds

DEFF Research Database (Denmark)

van den Berg, Irene; Guldbrandtsen, Bernt; Hozé, C

Our objective was to investigate the potential benefits of using sequence data to improve across breed genomic prediction, using data from five French and Danish dairy cattle breeds. First, QTL for protein yield were detected using high density genotypes. Part of the QTL detected within breed was...

Tritium breeding materials

International Nuclear Information System (INIS)

Hollenberg, G.W.; Johnson, C.E.; Abdou, M.

1984-03-01

Tritium breeding materials are essential to the operation of D-T fusion facilities. Both of the present options - solid ceramic breeding materials and liquid metal materials are reviewed with emphasis not only on their attractive features but also on critical materials issues which must be resolved

Tritium breeding materials

International Nuclear Information System (INIS)

Hollenberg, G.W.; Johnson, C.E.; Abdou, M.A.

1984-01-01

Tritium breeding materials are essential to the operation of D-T fusion facilities. Both of the present options - solid ceramic breeding materials and liquid metal materials are reviewed with emphasis not only on their attractive features but also on critical materials issues which must be resolved

Double spike methodology for uranium determination by thermal ionisation mass spectrometry: separation and purification of 234U

International Nuclear Information System (INIS)

Shah, P.M.; Saxena, M.K.; Sanjai Kumar; Aggarwal, S.K.; Jain, H.C.

1995-01-01

With an objective to prepare double spike of 233 U+ 234 U for determination of uranium concentration by Isotopic Dilution Thermal Ionisation Mass Spectrometry (ID-TIMS), 234 U was separated and purified from aged 238 Pu sample (15 years old) using several ion exchange and solvent extraction procedures. Final product containing 95% and 5% alpha activities of 234 and 238 Pu, respectively, which translates into 99.998 atom% of 234 U and 0.002 atom% of 238 Pu was found suitable for double spike. (author). 1 ref

The influence of cross-breeding Zlotnicka Spotted native breed sows ...

African Journals Online (AJOL)

To sum up, it is possible to say that the raw meat of Zlotnicka Spotted pigs and their cross-breeds with Duroc and Polish Large White breeds is characterised by good quality and because of its considerable intramuscular fat content, it has a high culinary and processing value, especially for ripening products. Key words: Pigs ...

The effect of dissolved hydrogen on the dissolution of 233U doped UO2(s) high burn-up spent fuel and MOX fuel

International Nuclear Information System (INIS)

Carbol, P.; Spahiu, K.

2005-03-01

In this report the results of the experimental work carried out in a large EU-research project (SFS, 2001-2004) on spent fuel stability in the presence of various amounts of near field hydrogen are presented. Studies of the dissolution of 233 U doped UO 2 (s) simulating 'old' spent fuel were carried out as static leaching tests, autoclave tests with various hydrogen concentrations and electrochemical tests. The results of the leaching behaviour of a high burn-up spent fuel pellet in 5 M NaCl solutions in the presence of 3.2 bar H 2 pressure and of MOX fuel in dilute synthetic groundwater under 53 bar H 2 pressure are also presented. In all the experimental studies carried out in this project, a considerable effect of hydrogen in the dissolution rates of radioactive materials was observed. The experimental results obtained in this project with a-doped UO 2 , high burn-up spent fuel and MOX fuel together with literature data give a reliable background to use fractional alteration/dissolution rates for spent fuel of the order of 10 -6 /yr - 10 -8 /yr with a recommended value of 4x10 -7 /yr for dissolved hydrogen concentrations above 10 -3 M and Fe(II) concentrations typical for European repository concepts. Finally, based on a review of the experimental data and available literature data, potential mechanisms of the hydrogen effect are also discussed. The work reported in this document was performed as part of the Project SFS of the European Commission 5th Framework Programme under contract no FIKW-CT-2001-20192 SFS. It represents the deliverable D10 of the experimental work package 'Key experiments using a-doped UO 2 and real spent fuel', coordinated by SKB with the participation of ITU, FZK-INE, ENRESA, CIEMAT, ARMINES-SUBATECH and SKB

Nuclear analysis and performance of the Light Water Breeder Reactor (LWBR) core power operation at Shippingport

International Nuclear Information System (INIS)

Hecker, H.C.

1984-04-01

This report presents the nuclear analysis and discusses the performance of the LWBR core at Shippingport during power operation from initial startup through end-of-life at 28,730 EFPH. Core follow depletion calculations confirmed that the reactivity bias and power distributions were well within the uncertainty allowances used in the design and safety analysis of LWBR. The magnitude of the core follow reactivity bias has shown that the calculational models used can predict the behavior of U 233 -Th systems with closely spaced fuel rod lattices and movable fuel. In addition, the calculated final fissile loading is sufficiently greater than the initial fissile inventory that the measurements to be performed for proof-of-breeding evaluations are expected to confirm that breeding has occurred

A novel hash based least significant bit (2-3-3) image steganography in spatial domain

OpenAIRE

Manjula, G. R.; Danti, Ajit

2015-01-01

This paper presents a novel 2-3-3 LSB insertion method. The image steganography takes the advantage of human eye limitation. It uses color image as cover media for embedding secret message.The important quality of a steganographic system is to be less distortive while increasing the size of the secret message. In this paper a method is proposed to embed a color secret image into a color cover image. A 2-3-3 LSB insertion method has been used for image steganography. Experimental results show ...

Centrifuge Study of Pilot Tolerance to Acceleration and the Effects of Acceleration on Pilot Performance

Science.gov (United States)

Creer, Brent Y.; Smedal, Harald A.; Wingrove, Rodney C.

1960-01-01

A research program the general objective of which was to measure the effects of various sustained accelerations on the control performance of pilots, was carried out on the Aviation Medical Acceleration Laboratory centrifuge, U.S. Naval Air Development Center, Johnsville, PA. The experimental setup consisted of a flight simulator with the centrifuge in the control loop. The pilot performed his control tasks while being subjected to acceleration fields such as might be encountered by a forward-facing pilot flying an atmosphere entry vehicle. The study was divided into three phases. In one phase of the program, the pilots were subjected to a variety of sustained linear acceleration forces while controlling vehicles with several different sets of longitudinal dynamics. Here, a randomly moving target was displayed to the pilot on a cathode-ray tube. For each combination of acceleration field and vehicle dynamics, pilot tracking accuracy was measured and pilot opinion of the stability and control characteristics was recorded. Thus, information was obtained on the combined effects of complexity of control task and magnitude and direction of acceleration forces on pilot performance. These tests showed that the pilot's tracking performance deteriorated markedly at accelerations greater than about 4g when controlling a lightly damped vehicle. The tentative conclusion was also reached that regardless of the airframe dynamics involved, the pilot feels that in order to have the same level of control over the vehicle, an increase in the vehicle dynamic stability was required with increases in the magnitudes of the acceleration impressed upon the pilot. In another phase, boundaries of human tolerance of acceleration were established for acceleration fields such as might be encountered by a pilot flying an orbital vehicle. A special pilot restraint system was developed to increase human tolerance to longitudinal decelerations. The results of the tests showed that human tolerance

ALARA review for the decontamination and decommissioning of the 233-S P.R. can loadout and decontamination

International Nuclear Information System (INIS)

Kornish, J.M.

1998-01-01

The 233-S Facility was completed in 1955 to expand plutonium production by further concentrating the plutonium nitrate product solution from the Reduction Oxidation (REDOX) Plant. The facility is radiologically contaminated because of operations and accidents. The building is presently a Hazard Category 2 Nuclear Facility. Disassembly of the loadout hood and its associated equipment may be done in parallel with the isolation of 233-S from REDOX via the pipe trench equipment removal. The work scope is to remove the entire loadout hood from the Product Receiver (P.R.) Can Loadout and Decon Room inside the 233-S Facility. A formal as low as reasonably achievable (ALARA) review is required by BHI-SH-02, Vol. 1, Procedure 1.22, Planning Radiological Work, when radiological conditions exceed trigger levels. The level of contamination inside the loadout hood and its associated equipment is unknown. The potential exists to exceed the level of loose surface contamination, which requires a formal ALARA review when opening the loadout hood and disassembly commences. This ALARA review is for the task instruction 1997-03-18-010 Revision 0, 233-S Loadout Hood Decon and Dismantlement

Genetic diversity of dog breeds: within-breed diversity comparing genealogical and molecular data.

Science.gov (United States)

Leroy, G; Verrier, E; Meriaux, J C; Rognon, X

2009-06-01

The genetic diversity of 61 dog breeds raised in France was investigated. Genealogical analyses were performed on the pedigree file of the French kennel club. A total of 1514 dogs were also genotyped using 21 microsatellite markers. For animals born from 2001 to 2005, the average coefficient of inbreeding ranged from 0.2% to 8.8% and the effective number of ancestors ranged from 9 to 209, according to the breed. The mean value of heterozygosity was 0.62 over all breeds (range 0.37-0.77). At the breed level, few correlations were found between genealogical and molecular parameters. Kinship coefficients and individual similarity estimators were, however, significantly correlated, with the best mean correlation being found for the Lynch & Ritland estimator (r = 0.43). According to both approaches, it was concluded that special efforts should be made to maintain diversity for three breeds, namely the Berger des Pyrénées, Braque Saint-Germain and Bull Terrier.

Evolution of actinides in ThO2 blanket of prototype fast breeder reactor

International Nuclear Information System (INIS)

Bachchan, Abhitab; Riyas, A.; Devan, K.; Puthiyavinayagam, P.

2015-01-01

The third stage of India's nuclear program focuses on fissile fuel production through Th- 233 U cycle in view of the better abundance and relative merits of thorium. For early introduction of Thorium into the nuclear energy system, several R and D program has started to find the best possible route of thorium utilization. Towards this, efforts were made to assess the feasibility of Th-U cycle in a fast spectrum reactor like Prototype Fast Breeder Reactor (PFBR). The effect on core neutronic parameters and actinide evolution with the replacement of depleted UO 2 in the PFBR blanket SA with thorium oxide has been studied using 3-D diffusion code FARCOB. Study shows that by the introduction of thorium blanket, core excess reactivity is coming down by ∼ 535 pcm and core breeding ratio is slightly lower than conventional oxide blanket. The distribution of region wise power production is slightly changed. Power from radial blanket is reduced from 3% to 2% while the core-1 power is increased from 49 % to 50 %. The estimated 233 U production is 7.6, 11.5 and 14.1 kg/t with 180, 360 and 540 days of irradiation respectively. (author)

Feasibility of Thorium Fuel Cycles in a Very High Temperature Pebble-Bed Hybrid System

Directory of Open Access Journals (Sweden)

L.P. Rodriguez

2015-08-01

Full Text Available Nuclear energy presents key challenges to be successful as a sustainable energy source. Currently, the viability of the use thorium-based fuel cycles in an innovative nuclear energy generation system is being investigated in order to solve these key challenges. In this work, the feasibility of three thorium-based fuel cycles (232Th-233U, 232Th-239Pu, and 232Th-U in a hybrid system formed by a Very High Temperature Pebble-Bed Reactor (VHTR and two Pebble-Bed Accelerator Driven Systems (ADSs was evaluated using parameters related to the neutronic behavior such as nuclear fuel breeding, minor actinide stockpile, the energetic contribution of each fissile isotope, and the radiotoxicity of the long lived wastes. These parameters were used to compare the fuel cycles using the well-known MCNPX ver. 2.6e computational code. The results obtained confirm that the 232Th-233U fuel cycle is the best cycle for minimizing the production of plutonium isotopes and minor actinides. Moreover, the inclusion of the second stage in the ADSs demonstrated the possibility of extending the burnup cycle duration and reducing the radiotoxicity of the discharged fuel from the VHTR.

U.S. Nuclear Regulatory Commission Extremely Low Probability of Rupture pilot study: xLPR framework model user's guide

International Nuclear Information System (INIS)

Kalinich, Donald A.; Sallaberry, Cedric M.; Mattie, Patrick D.

2010-01-01

For the U.S. Nuclear Regulatory Commission (NRC) Extremely Low Probability of Rupture (xLPR) pilot study, Sandia National Laboratories (SNL) was tasked to develop and evaluate a probabilistic framework using a commercial software package for Version 1.0 of the xLPR Code. Version 1.0 of the xLPR code is focused assessing the probability of rupture due to primary water stress corrosion cracking in dissimilar metal welds in pressurizer surge nozzles. Future versions of this framework will expand the capabilities to other cracking mechanisms, and other piping systems for both pressurized water reactors and boiling water reactors. The goal of the pilot study project is to plan the xLPR framework transition from Version 1.0 to Version 2.0; hence the initial Version 1.0 framework and code development will be used to define the requirements for Version 2.0. The software documented in this report has been developed and tested solely for this purpose. This framework and demonstration problem will be used to evaluate the commercial software's capabilities and applicability for use in creating the final version of the xLPR framework. This report details the design, system requirements, and the steps necessary to use the commercial-code based xLPR framework developed by SNL.

Breeds in danger of extintion and biodiversity

OpenAIRE

A. Blasco

2008-01-01

Some arguments currently used to support breed conservation are examined. The central point is that we cannot conserve all breeds because we do not have financial resources enough to keep everything (mainly in developing countries) and in many cases we do not have special reasons to conserve breeds. A breed is a human product and it should not be confused with specie. A breed can be generated or transformed. We can create synthetic breeds with the best characteristics of several breeds. Selec...

Genomics-assisted breeding in fruit trees.

Science.gov (United States)

Iwata, Hiroyoshi; Minamikawa, Mai F; Kajiya-Kanegae, Hiromi; Ishimori, Motoyuki; Hayashi, Takeshi

2016-01-01

Recent advancements in genomic analysis technologies have opened up new avenues to promote the efficiency of plant breeding. Novel genomics-based approaches for plant breeding and genetics research, such as genome-wide association studies (GWAS) and genomic selection (GS), are useful, especially in fruit tree breeding. The breeding of fruit trees is hindered by their long generation time, large plant size, long juvenile phase, and the necessity to wait for the physiological maturity of the plant to assess the marketable product (fruit). In this article, we describe the potential of genomics-assisted breeding, which uses these novel genomics-based approaches, to break through these barriers in conventional fruit tree breeding. We first introduce the molecular marker systems and whole-genome sequence data that are available for fruit tree breeding. Next we introduce the statistical methods for biparental linkage and quantitative trait locus (QTL) mapping as well as GWAS and GS. We then review QTL mapping, GWAS, and GS studies conducted on fruit trees. We also review novel technologies for rapid generation advancement. Finally, we note the future prospects of genomics-assisted fruit tree breeding and problems that need to be overcome in the breeding.

A review of the breeding potentials of carbide, nitride and oxide fueled LMFBRs and GCFRs

International Nuclear Information System (INIS)

Handa, Muneo

1977-11-01

The effects of design parameters in large variation on compound system doubling time of large advanced-fueled LMFBR are described on the base of recent U.S. results. The fuel element design by Combustion Engineering Inc. in step-by-step substitution of the initial oxide fuel subassemblies with carbide ones is explained. Breeding characteristics of the oxide-fueled LMFBR and its potential design modifications are expounded. The gas cooled fast breeder program in West Germany and in the United States are briefed. Definitions of the breeding ratio and doubling time in overall fuel cycle are given. (auth.)

Genomic analyses of modern dog breeds.

Science.gov (United States)

Parker, Heidi G

2012-02-01

A rose may be a rose by any other name, but when you call a dog a poodle it becomes a very different animal than if you call it a bulldog. Both the poodle and the bulldog are examples of dog breeds of which there are >400 recognized worldwide. Breed creation has played a significant role in shaping the modern dog from the length of his leg to the cadence of his bark. The selection and line-breeding required to maintain a breed has also reshaped the genome of the dog, resulting in a unique genetic pattern for each breed. The breed-based population structure combined with extensive morphologic variation and shared human environments have made the dog a popular model for mapping both simple and complex traits and diseases. In order to obtain the most benefit from the dog as a genetic system, it is necessary to understand the effect structured breeding has had on the genome of the species. That is best achieved by looking at genomic analyses of the breeds, their histories, and their relationships to each other.

A study on physical characteristics of supercritical light - water reactor loaded with (232U-238Th-238U) oxide fuel

International Nuclear Information System (INIS)

Kulikov, E. G.; Shmelev, A. N.; Apse, V. A.; Kulikov, G. G.

2007-01-01

The attractiveness of using (U-Th)-fuel in supercritical light water reactor is considered. The dilution of 2 33U in 2 38U is proposed with the purpose of increasing non-proliferation of this fissile isotope. Comparison of different fuel compositions is accomplished from the point of view of fissile isotope breeding and achieved burn-up; parasitic neutron absorption cross-sections are also compared. It is analyzed the impact for neutron balance of both cladding materials: zirconium alloy and stainless steel

Sire breed and breed genotype of dam effects in crossbreeding beef ...

African Journals Online (AJOL)

Cows bred to Afrikaner bulls were less (P < 0.05) productive than cows bred to other Bos taurus sires. An increase in proportion Afrikaner breeding in dam resulted in longer calving intervals and a decline in cow productivity, but these differences were not always significant. A breeding strategy for the retainment of superior ...

A Strategy for the Third Breeding Cycle of Loblolly Pine in the Southeastern U.S.

Science.gov (United States)

S.E. McKeand; F.E. Bridgwater

1998-01-01

A strategy for the North Carolina State University - Industry Cooperative Tree Improvement Program's third-cycle breeding for loblolly pine (Pinus taeda L.) was developed to provide genetic gain in the short-term as well as to maintain genetic diversity so that long-term genetic gains will also be possible. Our strategy will be to manage a...

Seaside, Oregon, Tsunami Vulnerability Assessment Pilot Study

Science.gov (United States)

Dunbar, P. K.; Dominey-Howes, D.; Varner, J.

2006-12-01

The results of a pilot study to assess the risk from tsunamis for the Seaside-Gearhart, Oregon region will be presented. To determine the risk from tsunamis, it is first necessary to establish the hazard or probability that a tsunami of a particular magnitude will occur within a certain period of time. Tsunami inundation maps that provide 100-year and 500-year probabilistic tsunami wave height contours for the Seaside-Gearhart, Oregon, region were developed as part of an interagency Tsunami Pilot Study(1). These maps provided the probability of the tsunami hazard. The next step in determining risk is to determine the vulnerability or degree of loss resulting from the occurrence of tsunamis due to exposure and fragility. The tsunami vulnerability assessment methodology used in this study was developed by M. Papathoma and others(2). This model incorporates multiple factors (e.g. parameters related to the natural and built environments and socio-demographics) that contribute to tsunami vulnerability. Data provided with FEMA's HAZUS loss estimation software and Clatsop County, Oregon, tax assessment data were used as input to the model. The results, presented within a geographic information system, reveal the percentage of buildings in need of reinforcement and the population density in different inundation depth zones. These results can be used for tsunami mitigation, local planning, and for determining post-tsunami disaster response by emergency services. (1)Tsunami Pilot Study Working Group, Seaside, Oregon Tsunami Pilot Study--Modernization of FEMA Flood Hazard Maps, Joint NOAA/USGS/FEMA Special Report, U.S. National Oceanic and Atmospheric Administration, U.S. Geological Survey, U.S. Federal Emergency Management Agency, 2006, Final Draft. (2)Papathoma, M., D. Dominey-Howes, D.,Y. Zong, D. Smith, Assessing Tsunami Vulnerability, an example from Herakleio, Crete, Natural Hazards and Earth System Sciences, Vol. 3, 2003, p. 377-389.

Influence of cross-breeding of native breed sows of Zlotnicka spotted ...

African Journals Online (AJOL)

The aim of this study was the estimation of the cross-breeding influence of Zlotnicka spotted sows with boars of polish large white and Duroc breeds on carcass traits of fatteners. 50 pigs were divided into four groups: Zlotnicka spotted (ZS), Zlotnicka spotted x polish large white (ZS x PLW), Zlotnicka spotted x Duroc (ZS x D) ...

Breeding Jatropha curcas by genomic selection: A pilot assessment of the accuracy of predictive models.

Science.gov (United States)

Azevedo Peixoto, Leonardo de; Laviola, Bruno Galvêas; Alves, Alexandre Alonso; Rosado, Tatiana Barbosa; Bhering, Leonardo Lopes

2017-01-01

Genomic wide selection is a promising approach for improving the selection accuracy in plant breeding, particularly in species with long life cycles, such as Jatropha. Therefore, the objectives of this study were to estimate the genetic parameters for grain yield (GY) and the weight of 100 seeds (W100S) using restricted maximum likelihood (REML); to compare the performance of GWS methods to predict GY and W100S; and to estimate how many markers are needed to train the GWS model to obtain the maximum accuracy. Eight GWS models were compared in terms of predictive ability. The impact that the marker density had on the predictive ability was investigated using a varying number of markers, from 2 to 1,248. Because the genetic variance between evaluated genotypes was significant, it was possible to obtain selection gain. All of the GWS methods tested in this study can be used to predict GY and W100S in Jatropha. A training model fitted using 1,000 and 800 markers is sufficient to capture the maximum genetic variance and, consequently, maximum prediction ability of GY and W100S, respectively. This study demonstrated the applicability of genome-wide prediction to identify useful genetic sources of GY and W100S for Jatropha breeding. Further research is needed to confirm the applicability of the proposed approach to other complex traits.

Breeding Jatropha curcas by genomic selection: A pilot assessment of the accuracy of predictive models.

Directory of Open Access Journals (Sweden)

Leonardo de Azevedo Peixoto

Full Text Available Genomic wide selection is a promising approach for improving the selection accuracy in plant breeding, particularly in species with long life cycles, such as Jatropha. Therefore, the objectives of this study were to estimate the genetic parameters for grain yield (GY and the weight of 100 seeds (W100S using restricted maximum likelihood (REML; to compare the performance of GWS methods to predict GY and W100S; and to estimate how many markers are needed to train the GWS model to obtain the maximum accuracy. Eight GWS models were compared in terms of predictive ability. The impact that the marker density had on the predictive ability was investigated using a varying number of markers, from 2 to 1,248. Because the genetic variance between evaluated genotypes was significant, it was possible to obtain selection gain. All of the GWS methods tested in this study can be used to predict GY and W100S in Jatropha. A training model fitted using 1,000 and 800 markers is sufficient to capture the maximum genetic variance and, consequently, maximum prediction ability of GY and W100S, respectively. This study demonstrated the applicability of genome-wide prediction to identify useful genetic sources of GY and W100S for Jatropha breeding. Further research is needed to confirm the applicability of the proposed approach to other complex traits.

Fission cross sections of some thorium, uranium, neptunium and plutonium isotopes relative to /sup 235/U

Energy Technology Data Exchange (ETDEWEB)

Meadows, J W

1983-10-01

Earlier results from the measurements, at this Laboratory, of 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, /sup 240/Pu, and /sup 242/Pu relative to /sup 235/U are reviewed with revisions to include changes in data processing procedures, alpha half lives and thermal fission cross sections. Some new data have also been included. The current experimental methods and procedures and the sample assay methods are described in detail and the sources of error are presented in a systematic manner. 38 references.

Willet M. Hays, great benefactor to plant breeding and the founder of our association.

Science.gov (United States)

Troyer, A F; Stoehr, H

2003-01-01

Willet M. Hays was a great benefactor to plant breeding and the founder of the American Genetic Association (AGA). We commemorate the AGA's centennial. We mined university archives, U.S. Department of Agriculture (USDA) yearbooks, plant breeding textbooks, scientific periodicals, and descendants for information. Willet Hays first recognized the individual plant as the unit of selection and started systematic pure-line selection and progeny tests in 1888. He developed useful plant breeding methods. He selected superior flax (Linum usitatissimum L.), wheat (Triticum vulgare L.), corn (Zea mays L.), barley (Hordeum vulgare L.), and oat (Avena sativa L.) varieties, and discovered Grimm alfalfa (Medicago sativa L.); all became commercially important. He initiated branch stations for better performance testing. Willet Hays befriended colleagues in other universities, in federal stations, in a London conference, and in Europe. He gathered and spread the scientific plant breeding gospel. He also improved rural roads and initiated animal breeding records and agricultural economics records. He started the AGA in 1903, serving as secretary for 10 years. He became assistant secretary of agriculture in 1904. He introduced the project system for agricultural research. He authored or coauthored the Nelson Amendment, the Smith-Lever Act, the Smith-Hughes Act, and the protocol leading to the United Nations Food and Agriculture Organization-all involved teaching agricultural practices that improved the world.

Sampling and Analysis Plan for the 233-S Plutonium Concentration Facility

International Nuclear Information System (INIS)

Mihalic, M.A.

1998-02-01

This Sampling and Analysis Plan (SAP) provides the information and instructions to be used for sampling and analysis activities in the 233-S Plutonium Concentration Facility. The information and instructions herein are separated into three parts and address the Data Quality Objective (DQO) Summary Report, Quality Assurance Project Plan (QAP), and SAP

ROOT VEGETABLES, BREEDING TRENDS, RESULTS

Directory of Open Access Journals (Sweden)

M. I. Fedorova

2017-01-01

Full Text Available The main advantage of root vegetables is their unique specificity and high economic importance. The benefits and medicinal properties of root vegetables being highly demanded by the market requirements to the commodity are highlighted in the article. The main directions of breeding program for root vegetable crops, including species of Apiaceae family with carrot, parsnips; Chenopodioideae family with red beet; Brassicaceae family with radish, Daikon, Raphanus sativus L. var. lobo Sazonova & Stank, turnip and rutabaga. Initial breeding accessions of carrot, red beet, radish, Daikon, Raphanus sativus L. var. lobo Sazonova & Stank, turnip and rutabaga have been selected out to be used for breeding program for heterosis. The mf and ms breeding lines were developed, and with the use of them the new gene pool was created. Variety supporting breeding program and methods were also proposed. 

Conservation priorities for Ethiopian sheep breeds combining threat status, breed merits and contributions to genetic diversity

NARCIS (Netherlands)

Gizaw, S.; Komen, J.; Windig, J.J.; Hanotte, O.; Arendonk, van J.A.M.

2008-01-01

Prioritizing livestock breeds for conservation needs to incorporate both genetic and non-genetic aspects important for the survival of the breeds. Here, we apply a maximum-utility-strategy to prioritize 14 traditional Ethiopian sheep breeds based on their threat status, contributions to farmer

Welfare in horse breeding

DEFF Research Database (Denmark)

Campbell, M.L.H.; Sandøe, Peter

2015-01-01

and identifies areas in which data is lacking. We suggest that all methods of horse breeding are associated with potential welfare problems, but also that the judicious use of ARTs can sometimes help to address those problems. We discuss how negative welfare effects could be identified and limited and how...... positive welfare effects associated with breeding might be maximised. Further studies are needed to establish an evidence base about how stressful or painful various breeding procedures are for the animals involved, and what the lifetime welfare implications of ARTs are for future animal generations....

Effect on milk production of F1 crossbreds resulted from Alpine breed (♂ x Albanian local goat breed (♀

Directory of Open Access Journals (Sweden)

Kristaq Kume

2012-07-01

Full Text Available About 950,000 goats, farmed mostly in hilly and mountainous areas of Albania, contribute about 8% of the country’s total milk production. In order to increase milk production, farmers are currently using crosses of the local goat breed with exotic breeds, mainly the Alpine breed from France. This study examines milk production data of first lactation from 45 goats of the local breed, 82 goats of the Alpine breed and 58 F1 crosses (♂Alpine breed x ♀local breed. The goats were kept on small-scale farms according to the traditional Albanian system. Milking was carried out in the morning and evening. Kids were weaned at 65 days of age after which milking started. Milk yield was recorded twice with a 15-day interval between the two readings. Total milk yield was calculated using the Fleischmann method. The F1 goats produced 37.8 kg more milk than local breed goats although the lactation length (P<0.05 of F1 goats was six days shorter compared to that of local breed goats (P<0.05. Analysis of variance showed a highly significant effect (P<0.01 of the genotype factor on milk production. The average Cappio-Borlino curves of three genotypes indicated that the lactation curves of local breed and F1 crosses were similar. Although the F1 cross goats had 50% of their genomes from a genetically improved breed they were still able to deal with the difficult conditions that characterize the traditional extensive farming systems in Albania. Breeding pure Alpine breed or its crosses with the local goat breed improved milk production in an extensive traditional system.

Migration patterns and wintering range of common loons breeding in the Northeastern United States

Science.gov (United States)

Kenow, K.P.; Adams, D.; Schoch, N.; Evers, D.C.; Hanson, W.; Yates, D.; Savoy, L.; Fox, T.J.; Major, A.; Kratt, R.; Ozard, J.

2009-01-01

A study, using satellite telemetry, was conducted to determine the precise migration patterns and wintering locations of Common Loons (Gavia immer) breeding in the northeastern United States. Transmitters were implanted in 17 loons (16 adults and one juvenile) that were captured on breeding lakes in New York, New Hampshire, and Maine during the summers of 2003, 2004, and 2005. Transmitters from ten of the birds provided adequate location data to document movement to wintering areas. Most adult loons appeared to travel non-stop from breeding lakes, or neighboring lakes (within 15 km), to the Atlantic coast. Adult loons marked in New Hampshire and Maine wintered 152 to 239 km from breeding lakes, along the Maine coast. Adult loons marked in the Adirondack Park of New York wintered along the coasts of Massachusetts (414 km from breeding lake), Rhode Island (362 km), and southern New Jersey (527 km). Most of the loons remained relatively stationary throughout the winter, but the size of individual wintering areas of adult loons ranged from 43 to 1,159 km 2, based on a 95% fixed kernel utilization distribution probability. A juvenile bird from New York made a number of stops at lakes and reservoirs en route to Long Island Sound (325 km from breeding lake). Maximum functional life of transmitters was about 12 months, providing an opportunity to document spring migration movements as well. This work provides essential information for development and implementation of regional Common Loon conservation strategies in the Northeastern U.S.

Fiscal Year 2008 Phased Construction Completion Report for EU Z2-33 in Zone 2, East Tennessee Technology Park, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Bechtel Jacobs

2008-09-11

Completion Report for the Zone 2 Soils, Slabs, and Subsurface Structures at East Tennessee Technology Park, Oak Ridge, Tennessee (DOE/OR/01-2317&D2). Remedial actions performed in the Balance of Site (BOS) Laboratory Area of EU Z2-33 and two small areas in EU Z2-42 are described in Sects. 5 through 10 of this Phased Construction Completion Report (PCCR). The purpose of this PCCR is to address the following: (1) Document DVS characterization results for EU Z2-33; (2) Describe and document the risk evaluation and determine if the EU meets the Zone 2 ROD requirements for unrestricted industrial use to 10 ft bgs; (3) Identify additional areas not defined in the Zone 2 ROD that require remediation based on the DVS evaluation results; and (4) Describe RAs performed in the EU Z2-33 BOS Laboratory Area and two small areas in EU Z2-42. Approximately 18 acres in EU Z2-33 are addressed in this PCCR. Based on the results of the DVS evaluation and RAs performed, all 18 acres are recommended for unrestricted industrial use to 10 ft bgs. Three Federal Facility Agreement sites are addressed and recommended for no further action within this acreage, including: (1) K-1004-L Recirculating Cooling Water Lines Leak Sites; (2) K-1044 Heavy Equipment Repair Shop; and (3) K-1015-A Laundry Pit. Remedial actions for EU Z2-33 were developed in response to DVS characterization results described in the EU Z2-33 Technical Memorandum (Appendix A) and to support reindustrialization of the East Tennessee Technology Park as a commercial industrial park. Remediation criteria were designed for the protection of a future industrial worker who normally would not have the potential for exposure to soil below 10ft bgs. Accordingly, the Zone 2 ROD required land use controls to prevent disturbance of soils below 10 ft deep and to restrict future land use to industrial/commercial activities. In response to stakeholder comments, the U.S. Department of Energy agreed to re-evaluate the need for such land use

75 FR 75532 - Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report

Science.gov (United States)

2010-12-03

...] Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report AGENCY: Federal Highway... participating in the Pilot Program, 23 U.S.C. 327(g) mandates semiannual audits during each of the first 2 years of State participation. This notice announces and solicits comments on the fifth audit report for the...

76 FR 5237 - Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report

Science.gov (United States)

2011-01-28

...] Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report AGENCY: Federal Highway... participating in the Pilot Program, 23 U.S.C. 327(g) mandates semiannual audits during each of the first 2 years of State participation. This final report presents the findings from the fifth FHWA audit of the...

77 FR 26355 - Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report

Science.gov (United States)

2012-05-03

...] Surface Transportation Project Delivery Pilot Program; Caltrans Audit Report AGENCY: Federal Highway... participating in the Pilot Program, 23 U.S.C. 327(g) mandates semiannual audits during each of the first 2 years of State participation. This final report presents the findings from the sixth FHWA audit of the...

Feasibility assessment of the once-through thorium fuel cycle for the PTVM LWR concept

International Nuclear Information System (INIS)

Rachamin, R.; Fridman, E.; Galperin, A.

2015-01-01

Highlights: • The PTVM LWR is an innovation reactor concept operating in a “breed & burn” mode. • An advanced once-through thorium fuel cycle for the PTVM LWR concept is proposed. • The PTVM LWR concept makes use of a seed-blanket geometry. • A novel fuel management scheme based on two separate fuel flow routes is analyzed. • The analysis indicates a potential for utilizing the fuel in an efficient manner. - Abstract: This paper investigates the feasibility of a once-through thorium fuel cycle for the novel reactor-design concept named the pressure tube light water reactor with variable moderator control (PTVM LWR). The PTVM LWR operates in a “breed & burn” mode, which makes it an attractive system for utilizing thorium fuel in a once-through mode. The “breed & burn” mode can emphasize the in situ generation as well as incineration of 233 U, which are the basic foundations of the once-through thorium fuel cycle. The PTVM LWR concept makes use of a seed–blanket geometry, whereby the core is divided into separated regions of thorium-based fuel channel assemblies (blanket) and low-enriched uranium (LEU) based fuel channel assemblies (seed). A novel fuel in-core management scheme based on two separate fuel flow routes (i.e., seed route and blanket route) is proposed and analyzed. Neutronic performance analysis indicates that the proposed novel fuel in-core management scheme has the potential to utilize both LEU- and thorium-based fuel in an efficient manner. The once-through thorium cycle, presented and discussed in this paper, provide interesting research leads and can serve as a bridge between current LEU-based fuel cycles and a thorium fuel cycle based on recycling of 233 U

Efficient Breeding by Genomic Mating.

Science.gov (United States)

Akdemir, Deniz; Sánchez, Julio I

2016-01-01

Selection in breeding programs can be done by using phenotypes (phenotypic selection), pedigree relationship (breeding value selection) or molecular markers (marker assisted selection or genomic selection). All these methods are based on truncation selection, focusing on the best performance of parents before mating. In this article we proposed an approach to breeding, named genomic mating, which focuses on mating instead of truncation selection. Genomic mating uses information in a similar fashion to genomic selection but includes information on complementation of parents to be mated. Following the efficiency frontier surface, genomic mating uses concepts of estimated breeding values, risk (usefulness) and coefficient of ancestry to optimize mating between parents. We used a genetic algorithm to find solutions to this optimization problem and the results from our simulations comparing genomic selection, phenotypic selection and the mating approach indicate that current approach for breeding complex traits is more favorable than phenotypic and genomic selection. Genomic mating is similar to genomic selection in terms of estimating marker effects, but in genomic mating the genetic information and the estimated marker effects are used to decide which genotypes should be crossed to obtain the next breeding population.

A computational approach to animal breeding.

Science.gov (United States)

Berger-Wolf, Tanya Y; Moore, Cristopher; Saia, Jared

2007-02-07

We propose a computational model of mating strategies for controlled animal breeding programs. A mating strategy in a controlled breeding program is a heuristic with some optimization criteria as a goal. Thus, it is appropriate to use the computational tools available for analysis of optimization heuristics. In this paper, we propose the first discrete model of the controlled animal breeding problem and analyse heuristics for two possible objectives: (1) breeding for maximum diversity and (2) breeding a target individual. These two goals are representative of conservation biology and agricultural livestock management, respectively. We evaluate several mating strategies and provide upper and lower bounds for the expected number of matings. While the population parameters may vary and can change the actual number of matings for a particular strategy, the order of magnitude of the number of expected matings and the relative competitiveness of the mating heuristics remains the same. Thus, our simple discrete model of the animal breeding problem provides a novel viable and robust approach to designing and comparing breeding strategies in captive populations.

Diversifying Selection Between Pure-Breed and Free-Breeding Dogs Inferred from Genome-Wide SNP Analysis

Directory of Open Access Journals (Sweden)

Małgorzata Pilot

2016-08-01

Full Text Available Domesticated species are often composed of distinct populations differing in the character and strength of artificial and natural selection pressures, providing a valuable model to study adaptation. In contrast to pure-breed dogs that constitute artificially maintained inbred lines, free-ranging dogs are typically free-breeding, i.e., unrestrained in mate choice. Many traits in free-breeding dogs (FBDs may be under similar natural and sexual selection conditions to wild canids, while relaxation of sexual selection is expected in pure-breed dogs. We used a Bayesian approach with strict false-positive control criteria to identify FST-outlier SNPs between FBDs and either European or East Asian breeds, based on 167,989 autosomal SNPs. By identifying outlier SNPs located within coding genes, we found four candidate genes under diversifying selection shared by these two comparisons. Three of them are associated with the Hedgehog (HH signaling pathway regulating vertebrate morphogenesis. A comparison between FBDs and East Asian breeds also revealed diversifying selection on the BBS6 gene, which was earlier shown to cause snout shortening and dental crowding via disrupted HH signaling. Our results suggest that relaxation of natural and sexual selection in pure-breed dogs as opposed to FBDs could have led to mild changes in regulation of the HH signaling pathway. HH inhibits adhesion and the migration of neural crest cells from the neural tube, and minor deficits of these cells during embryonic development have been proposed as the underlying cause of “domestication syndrome.” This suggests that the process of breed formation involved the same genetic and developmental pathways as the process of domestication.

ExoU contributes to late killing of Pseudomonas aeruginosa - infected endothelial cells ExoU contribui para a morte tardia de células endoteliais infectadas por Pseudomonas aeruginosa

Directory of Open Access Journals (Sweden)

Alessandra Mattos Saliba

2003-11-01

Full Text Available To ascertain the role of ExoU in late P. aeruginosa cytotoxicity, endothelial cells (EC were exposed to wild type PA103, PA103deltaexoU and PA103::exsA for 1h and to gentamicin in culture medium. After 24h, the viability of PA103-infected cells (33.7 ± 14.3% was significantly lower than the viability of PA103deltaexoU- (77.7 ± 6.3% or PA103::exsA- (79.5 ± 23.3% infected EC. P. aeruginosa cytotoxicity did not depend on the bacterial ability to interact with EC because the percentage of cells with associated PA103 (35.9 ± 15.8% was similar to the percentage in PA103deltaexoU- (34.2 ± 16.0% and lower than the percentage in PA103::exsA-infected cultures (82.9 ± 18.9%. Cell treatment with cytochalasin D reduced the PA103 internalization by EC but did not interfere with its ability to kill host cells.Para determinar o papel de ExoU na citotoxicidade tardia de P. aeruginosa, células endoteliais (CE foram expostas às cepas PA103, PA103deltaxoU e PA103::exsA por 1h e à gentamicina em meio de cultura. Após 24h, a viabilidade das CE infectadas com PA103 (33.7 ± 14.3% foi inferior à de CE infectadas com PA103deltaexoU (77.7 ± 6.3% e PA103::exsA (79.5 ± 23.3%. A citotoxicidade não dependeu da capacidade de interagir com as CE porque o percentual de células com bactérias associadas em culturas expostas a PA103 foi semelhante ao percentual em culturas expostas a PA103deltaexoU e inferior em culturas expostas a PA103::exsA. O tratamento das CE com citocalasina D reduziu a internalização de PA103, mas não interferiu em sua citotoxicidade.

Breeds in danger of extintion and biodiversity

Directory of Open Access Journals (Sweden)

A. Blasco

2008-07-01

Full Text Available Some arguments currently used to support breed conservation are examined. The central point is that we cannot conserve all breeds because we do not have financial resources enough to keep everything (mainly in developing countries and in many cases we do not have special reasons to conserve breeds. A breed is a human product and it should not be confused with specie. A breed can be generated or transformed. We can create synthetic breeds with the best characteristics of several breeds. Selection is not exhausting genetic variability (there are several experiments showing that, and genetic variability within breeds is large. We need reasons to keep breeds in danger in extinction. A breed is a tool, and we can decide to keep it when it is useful because it is specially adapted to some environments (although in this case it should not be in danger of extinction, it can be useful in crossbreeding to shorten the way of obtaining response to selection, or it has some extreme values for traits that may be useful in the future (in this case we have to define clearly which traits and how we expect the future to be. We can add cultural reasons when we have money enough to spend in culture.

Genomics-assisted breeding in fruit trees

OpenAIRE

Iwata, Hiroyoshi; Minamikawa, Mai F.; Kajiya-Kanegae, Hiromi; Ishimori, Motoyuki; Hayashi, Takeshi

2016-01-01

Recent advancements in genomic analysis technologies have opened up new avenues to promote the efficiency of plant breeding. Novel genomics-based approaches for plant breeding and genetics research, such as genome-wide association studies (GWAS) and genomic selection (GS), are useful, especially in fruit tree breeding. The breeding of fruit trees is hindered by their long generation time, large plant size, long juvenile phase, and the necessity to wait for the physiological maturity of the pl...

Review: Towards the agroecological management of ruminants, pigs and poultry through the development of sustainable breeding programmes. II. Breeding strategies.

Science.gov (United States)

Phocas, F; Belloc, C; Bidanel, J; Delaby, L; Dourmad, J Y; Dumont, B; Ezanno, P; Fortun-Lamothe, L; Foucras, G; Frappat, B; González-García, E; Hazard, D; Larzul, C; Lubac, S; Mignon-Grasteau, S; Moreno, C R; Tixier-Boichard, M; Brochard, M

2016-11-01

Agroecology uses ecological processes and local resources rather than chemical inputs to develop productive and resilient livestock and crop production systems. In this context, breeding innovations are necessary to obtain animals that are both productive and adapted to a broad range of local contexts and diversity of systems. Breeding strategies to promote agroecological systems are similar for different animal species. However, current practices differ regarding the breeding of ruminants, pigs and poultry. Ruminant breeding is still an open system where farmers continue to choose their own breeds and strategies. Conversely, pig and poultry breeding is more or less the exclusive domain of international breeding companies which supply farmers with hybrid animals. Innovations in breeding strategies must therefore be adapted to the different species. In developed countries, reorienting current breeding programmes seems to be more effective than developing programmes dedicated to agroecological systems that will struggle to be really effective because of the small size of the populations currently concerned by such systems. Particular attention needs to be paid to determining the respective usefulness of cross-breeding v. straight breeding strategies of well-adapted local breeds. While cross-breeding may offer some immediate benefits in terms of improving certain traits that enable the animals to adapt well to local environmental conditions, it may be difficult to sustain these benefits in the longer term and could also induce an important loss of genetic diversity if the initial pure-bred populations are no longer produced. As well as supporting the value of within-breed diversity, we must preserve between-breed diversity in order to maintain numerous options for adaptation to a variety of production environments and contexts. This may involve specific public policies to maintain and characterize local breeds (in terms of both phenotypes and genotypes), which could

Breeding phenology of African Black Oystercatchers Haematopus ...

African Journals Online (AJOL)

The timing of the start and duration of breeding and the effect of these on breeding productivity were analysed for African Black Oystercatchers Haematopus moquini on Robben Island, South Africa, over three breeding seasons from 2001 to 2004. African Black Oystercatchers have a long breeding season, from November ...

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

Selective breeding in organic dairy production

NARCIS (Netherlands)

Nauta, W.J.

2009-01-01

Organic dairy farming started to take off in the early 1990s, when the European Union laid down organic standards for animal production. Until now, however, only incidental steps have been taken towards organic breeding and organic farmers mainly use breeding stock from conventional breeding

Breeding in a den of thieves

NARCIS (Netherlands)

Fouw, de Jimmy; Bom, Roeland A.; Klaassen, Raymond H.G.; Müskens, Gerard J.D.M.; Vries, de Peter P.; Popov, Igor Yu; Kokorev, Yakov I.; Ebbinge, Bart; Nolet, Bart A.

2016-01-01

Breeding success of many Arctic-breeding bird populations varies with lemming cycles due to prey switching behavior of generalist predators. Several bird species breed on islands to escape from generalist predators like Arctic fox Vulpes lagopus, but little is known about how these species

Genetic analysis of three South African horse breeds

Directory of Open Access Journals (Sweden)

E.G. Cothran

1998-07-01

Full Text Available Genetic variability at 7 blood-group and 10 biochemical genetic loci was examined in 3 South African horse breeds, the Nooitgedacht, Boerperd and Basuto Pony. Observed heterozygosity for these breeds was intermediate for domestic horses, with the highest heterozygosity in the Boerperd and the lowest in the Basuto Pony. The 3 breeds show greater genetic similarity to each other than to other domestic horse breeds. Compared to other breeds, the South African breeds show greater genetic similarity to breeds such as the Thoroughbred, Holstein, Trakehner and Hanovarian and also to North American breeds such as the Saddlebred, Standardbred and Morgan Horse.

29 CFR 779.233 - Independent contractors performing work “for” an enterprise.

Science.gov (United States)

2010-07-01

... Apply; Enterprise Coverage Leased Departments, Franchise and Other Business Arrangements § 779.233... section 3(r) has reference to an independent business which performs services for other businesses as an established part of its own business activities. The term “independent contractor” as used in 3(r) thus has...

Phase distribution studies in metallic alloy SIMFUEL

International Nuclear Information System (INIS)

Kolay, S.; Basu, M.; Kaity, S.; Das, D.

2014-01-01

Utilization of U-Pu based alloy fuel in the three stage nuclear power generation program in India is one of the important mandate due to shorter doubling time for breeding of the fissile isotopes ( 239 Pu and 233 U) to be used in Th based driver fuel in the 3rd stage. Reported information shows successful performance of fuel with porous alloy matrix in achieving 10-15 atom % burn-up. The porosity and microstructure of this alloy are strongly dependent on the composition and phases of the fission products incorporated in the matrix. The porosity influences the extent of fuel swelling and fission gas release, which affects the performance and integrity of the fuel. This study addresses to these issues taking the base alloy U-10wt% Zr

Semen quality of Italian local pig breeds

Directory of Open Access Journals (Sweden)

G. Gandini

2010-01-01

Full Text Available From 1996 to 1999 a conservation programme was carried out within the framework of EC contract “European gene banking project for the pig genetic resources” (Ollivier et al., 2001 in the Italian local pig breeds. The aims of the program included the primary characterization of the breeds, i.e. information on the organization in charge of the breed, breeding population numbers, breed description and qualifications, and field trials on productive and reproductive performances. In this context the “Semen Bank of Italian local pig breeds” was built. A total of 30,835 straws of four Italian local pig breeds (Cinta Senese, Casertana, Mora Romagnola and Nero Siciliano, collected from 42 sires, have been stored. In this work semen quality traits, lipid composition and freezability of the four Italian local pig breeds are reported.

United States Coast Pilot (volume 1 through 9)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The United States Coast Pilot is a series of 9 nautical books that cover a wide variety of information important to navigators of U.S. coastal and intercoastal...

Study of the production of uranium-233 in natural thorium subjected to a neutron flux of 14 MeV

International Nuclear Information System (INIS)

Abel, G.; Martel, J.G.; St Germain, J.P.

1979-01-01

This is a study of neutron flux and reactivity in several simplified models of a fusion reactor blanket composed of thorium, carbon and a stainless steel structure. The objective is the comparative determination, theoretical and experimental, of values for the conversion of nuclei of Th-232 into fissile U-233 nuclei in such a blanket. Theoretical calculations are carried out using the ANISN (transport equation) and MORSE (Monte Carlo) codes. Experimental values are measured in a stainless steel rack structure allowing simplified blanket models to be mounted around a 14 MeV neutron source. In the first year of work theoretical flux values have been obtained, the necesssary detectors constructed, the rack structure set up, programs worked out for the reactivity calculations, and finally verification methods worked out in conditions similar to those that will prevail. (LL) [fr

Breeding biology of the threadstalk milkvetch, Astragalus filipes (Fabaceae), with a review of the genus

Science.gov (United States)

Kristal M. Watrous; James H. Cane

2011-01-01

Astragalus L. (Fabaceae) is an enormous and diverse plant genus with a cosmopolitan distribution, but relatively few breeding biologies are known for its member species. Threadstalk (or basalt) milkvetch, Astragalus filipes Torrey ex. A. Gray, is common and widespread throughout the U.S. Intermountain West, including the Great Basin. It is being studied and ultimately...

Evolution, plant breeding and biodiversity

Directory of Open Access Journals (Sweden)

Salvatore Ceccarelli

2011-11-01

Full Text Available This paper deals with changes in biodiversity during the course of evolution, plant domestication and plant breeding. It shows than man has had a strong influence on the progressive decrease of biodiversity, unconscious at first and deliberate in modern times. The decrease in biodiversity in the agricultures of the North causes a severe threat to food security and is in contrasts with the conservation of biodiversity which is part of the culture of several populations in the South. The concluding section of the paper shows that man could have guided evolution in a different way and shows an example of participatory plant breeding, a type of breeding which is done in collaboration with farmers and is based on selection for specific adaptation. Even though participatory plant breeding has been practiced for only about 20 years and by relatively few groups, the effects on both biodiversity and crop production are impressive. Eventually the paper shows how participatory plant breeding can be developed into ‘evolutionary plant breeding’ to cope in a dynamic way with climate changes.

Future breeding for organic and low-input agriculture: integrating values and modern breeding tools for improving robustness

NARCIS (Netherlands)

Lammerts Van Bueren, E.

2010-01-01

Organic production and also the attention for plant breeding for organic agriculture is still increasing in Europe. The question often raised is how much does plant breeding for the organic sector differ from modern plant breeding and does a ban on GMO also include refraining from molecular marker

Spallation symbiont and thorium breeding

International Nuclear Information System (INIS)

Furukawa, Kazuo

1991-01-01

The medium term world energy and environment countermeasures for 2020-2070 are not yet clearly established. The forecast of energy situation hereafter, its problems and the measures for solution are considered. World trend is removing borders, and the north-south problems are increasing the importance. The rational and clear idea with the support of concrete technology is required. The demand of energy will increase enormously at the annual rate of 2.3%. The world energy situation was forecast considering the increase of population, and it will be 115 TW at the end of the next century. The present status, problems and the countermeasures in nuclear fission energy technology are explained. The countermeasures should be based on three principles, namely Th-U-233 cycle, the utilization of molten fluoride fuel medium and the separation of molten salt breeders and molten salt reactors. Accelerator molten salt breeders, small molten salt reactors, the nuclear fuel cycle and the annihilation process for radioactive wastes are reported. The perspective that the nuclear energy system, in which the reactor safety, the measures to wastes and others are improved by the spallation-fission symbiont using thorium molten salt as the working medium, can be constructed is shown. (K.I.)

Representations for the extreme zeros of orthogonal polynomials (vol 233, pg 847, 2009)

NARCIS (Netherlands)

van Doorn, Erik A.; van Foreest, Nicky D.; Zeifman, Alexander I.

2013-01-01

We correct representations for the endpoints of the true interval of orthogonality of a sequence of orthogonal polynomials that were stated by us in the Journal of Computational and Applied Mathematics 233 (2009) 847-851. (c) 2013 Elsevier B.V. All rights reserved.

Mutation breeding in malting barley

Energy Technology Data Exchange (ETDEWEB)

Hiraki, Makoto; Sanada, Matsuyoshi

1984-03-01

The released varieties of malting barley through mutation breeding is more than ten in number, including foreign varieties. In Japan four varieties has been released so far. We started mutation breeding in 1956 together with cross breeding that we employed before. Until now, Gamma 4, Amagi Nijo 1 and Fuji Nijo 2 have been produced from the direct use of induced mutations and Nirasaki Nijo 8 from the indirect use of them. Mutation breeding has been used mainly in the partial improvement of agronomic characteristics since the selection for malting quality was very complicated. As the variety bred by induced mutation is usually equivalent to the original variety in malting quality, both this new variety and the original one could be cultivated in the same area without any problem on later malt production. Particularly when one farmer cultivates barley in an extensive acreage, he can harvest at the best time according to the different maturing time of each variety. From these points of view, mutation breeding is an efficient tool in malting barley breeding. Mutagens we have used so far are X-rays, ..gamma..-rays, neutron and chemicals such as dES. From our experience in selection, the low dose of radiation and chemical mutagens are more effective in selection of point mutation than the high dose of radiation which tends to produce many abnormal but few practical mutants. (author).

HUD PowerSaver Pilot Loan Program

Energy Technology Data Exchange (ETDEWEB)

Zimring, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoffman, Ian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2010-12-10

The U.S. Department of Housing and Urban Development (HUD) recently announced the creation of a pilot loan program for home energy improvements. The PowerSaver loan program is a new, energy-focused variant of the Title I Property Improvement Loan Insurance Program (Title I Program) and is planned for introduction in early 2011. The PowerSaver pilot will provide lender insurance for secured and unsecured loans up to $25,000 to single family homeowners. These loans will specifically target residential energy efficiency and renewable energy improvements. HUD estimates the two-year pilot will fund approximately 24,000 loans worth up to $300 million; the program is not capped. The Federal Housing Administration (FHA), HUD's mortgage insurance unit, will provide up to $25 million in grants as incentives to participating lenders. FHA is seeking lenders in communities with existing programs for promoting residential energy upgrades.

Genetic characterization of four native Italian shepherd dog breeds and analysis of their relationship to cosmopolitan dog breeds using microsatellite markers.

Science.gov (United States)

Bigi, D; Marelli, S P; Randi, E; Polli, M

2015-12-01

Very little research into genetic diversity of Italian native dog breeds has been carried out so far. In this study we aimed to estimate and compare the genetic diversity of four native Italian shepherd dog breeds: the Maremma, Bergamasco, Lupino del Gigante and Oropa shepherds. Therefore, some cosmopolitan dog breeds, which have been widely raised in Italy for a long time past, have also been considered to check possible influence of these dog populations on the Italian autochthonous breeds considered here. A total of 212 individuals, belonging to 10 different dog breeds, were sampled and genotyped using 18 autosomal microsatellite loci. We analyzed the genetic diversity of these breeds, within breed diversity, breed relationship and population structure. The 10 breeds considered in this study were clearly genetically differentiated from each other, regardless of current population sizes and the onset of separate breeding history. The level of genetic diversity explained 20% of the total genetic variation. The level of H E found here is in agreement with that found by other studies. The native Italian breeds showed generally higher genetic diversity compared with the long established, well-defined cosmopolitan dog breeds. As the Border Collie seems closer to the Italian breeds than the other cosmopolitan shepherd dogs considered here, a possible utilization of this breed to improve working performance in Italian traditional working shepherd dogs cannot be ignored. The data and information found here can be utilized in the organization of conservation programs planned to reduce inbreeding and to minimize loss of genetic variability.

48 CFR 52.233-4 - Applicable Law for Breach of Contract Claim.

Science.gov (United States)

2010-10-01

... Provisions and Clauses 52.233-4 Applicable Law for Breach of Contract Claim. As prescribed in 33.215(b), insert the following clause: Applicable Law for Breach of Contract Claim (OCT 2004) United States law... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Applicable Law for Breach...

U.S. Nuclear Regulatory Commission Extremely Low Probability of Rupture pilot study : xLPR framework model user's guide.

Energy Technology Data Exchange (ETDEWEB)

Kalinich, Donald A.; Sallaberry, Cedric M.; Mattie, Patrick D.

2010-12-01

For the U.S. Nuclear Regulatory Commission (NRC) Extremely Low Probability of Rupture (xLPR) pilot study, Sandia National Laboratories (SNL) was tasked to develop and evaluate a probabilistic framework using a commercial software package for Version 1.0 of the xLPR Code. Version 1.0 of the xLPR code is focused assessing the probability of rupture due to primary water stress corrosion cracking in dissimilar metal welds in pressurizer surge nozzles. Future versions of this framework will expand the capabilities to other cracking mechanisms, and other piping systems for both pressurized water reactors and boiling water reactors. The goal of the pilot study project is to plan the xLPR framework transition from Version 1.0 to Version 2.0; hence the initial Version 1.0 framework and code development will be used to define the requirements for Version 2.0. The software documented in this report has been developed and tested solely for this purpose. This framework and demonstration problem will be used to evaluate the commercial software's capabilities and applicability for use in creating the final version of the xLPR framework. This report details the design, system requirements, and the steps necessary to use the commercial-code based xLPR framework developed by SNL.

Male and female breeding strategies in a cooperative primate.

Science.gov (United States)

Yamamoto, Maria Emilia; Araujo, Arrilton; Arruda, Maria de Fatima; Lima, Ana Karinne Moreira; Siqueira, Jose de Oliveira; Hattori, Wallisen Tadashi

2014-11-01

Marmosets are cooperative breeders organized as extended family groups, but breeding is generally restricted to a single pair. Breeding competition is fierce in female marmosets; males, on the other hand, show low levels of intragroup aggression. We investigated male and female breeding strategies and the resulting reproductive output in 9 wild groups. Reproductive output, tenure of breeding animals, identification of the breeding system, breeding position replacements, migration and infanticide were recorded; also, we recorded grooming and aggression. Replacement of the breeding male or female was observed on nine occasions. On four occasions, the son of the breeding male inherited the breeding post, but we never observed inheritance of a breeding post by a daughter. Mostly, females attained a breeding post by immigrating to a group that had a breeding vacancy. Our results showed that Callithrix jacchus males and females use different strategies to attain a breeding position and maintain it for as long as possible. These strategies prolong the tenure of the breeding position, which is the best way to produce a large number of offspring. This article is part of a Special Issue entitled: Neotropical Behaviour. Copyright © 2014 Elsevier B.V. All rights reserved.

Native Pig and Chicken Breed Database: NPCDB

Directory of Open Access Journals (Sweden)

Hyeon-Soo Jeong

2014-10-01

Full Text Available Indigenous (native breeds of livestock have higher disease resistance and adaptation to the environment due to high genetic diversity. Even though their extinction rate is accelerated due to the increase of commercial breeds, natural disaster, and civil war, there is a lack of well-established databases for the native breeds. Thus, we constructed the native pig and chicken breed database (NPCDB which integrates available information on the breeds from around the world. It is a nonprofit public database aimed to provide information on the genetic resources of indigenous pig and chicken breeds for their conservation. The NPCDB (http://npcdb.snu.ac.kr/ provides the phenotypic information and population size of each breed as well as its specific habitat. In addition, it provides information on the distribution of genetic resources across the country. The database will contribute to understanding of the breed’s characteristics such as disease resistance and adaptation to environmental changes as well as the conservation of indigenous genetic resources.

A study of rates of (n, f), (n, γ), and (n, 2n) reactions in natU and 232Th produced by the neutron fluence in the graphite set-up (gamma-3) irradiated by 2.33 GeV deuteron beam

International Nuclear Information System (INIS)

Adam, J.; Chitra Bhatia; Katovskij, K.

2011-01-01

Spallation neutrons produced in a collision of 2.33 GeV deuteron beam with the large lead target are moderated by the thick graphite block surrounding the target and used to activate the radioactive samples of nat U and Th put at the three different positions, identified as holes 'a', 'b' and 'c' in the graphite block. Rates of the (n, f), (n, γ), and (n, 2n) reactions in the two samples are determined using the gamma spectrometry. Ratio of the experimental reaction rates, R(n, 2n)/R(n, f) for the 232 Th and nat U are estimated in order to understand the role of reactions of (n, xn) type in Accelerator Driven Subcritical Systems. For the Th-sample, the ratio is ∼ 54(10)% in case of hole 'a' and ∼ 95(57)% in case of hole 'b' compared to 1.73(20)% for the hole 'a' and 0.710(9)% for the hole 'b' in case of the nat U sample. Also the ratio of fission rates in uranium to thorium, nat U(n, f)/ 232 Th(n, f), is ∼ 11.2(17) in case of hole 'a' and 26.8(85) in hole 'b'. Similarly, ratio 238 U(n, 2n)/ 232 Th(n, 2n) is 0.36(4) for the hole 'a' and 0.20(10) for the hole 'b' showing that 232 Th is more prone to the (n, xn) reaction than 238 U. All the experimental reaction rates are compared with the simulated ones by generating neutron fluxes at the three holes from MCNPX 2.6c and making use of LA150 library of cross sections. The experimental and calculated rates of all the three reactions are in good agreement. The transmutation power of the set-up is estimated using the rates of (n, γ) and (n, 2n) reactions for both the samples in the three holes and compared with some of the results of the 'Energy plus Transmutation' set-up and TARC experiment

ALARA Review of 233-S Process Hood D and D and Related Activities

International Nuclear Information System (INIS)

Landsman, S.D.

1999-01-01

This document is an as low as reasonably achievable (ALARA) review of design packages for planned work at the 233-S Facility. The ALARA review was initiated in accordance with the Bechtel Hanford, Inc. (BHI) Integrated Environmental, Safety, and Health Management System (ISMS) workflow process

Study of Advanced Reactor Mixed Oxide Fuel Production of (U,Th)O2

International Nuclear Information System (INIS)

Busron-Masduki; Damunir; Pristi-Hartati; R-Sukarsono; Bangun-Wasito

2000-01-01

The high price and starting scarcity of reserved of oil drive the people to drill the alternative nuclear energy. Accelerator-driven Transmutation Waste (ATW) is a prospective technology to solve the problem of used fuel waste, to reduce the anxiety of long term disposal waste, to increase the public acceptance of nuclear energy enter into the third millennium. The future of large nuclear energy appears in many-branched industry will depend on the capability to generate relatively low priced fuel on the basis of commercial nuclear energy. Utilization of uranium-233 -thorium cycle insures long-term fuel supply, makes the nuclear energy production more flexible and enables the self-provision regime to be realized in future. Flowsheet of mixed oxide fuel production for advanced reactor of (U,Th)O 2 is a combination of existing manufacturing equipment and quality assurance program from commercial LWR and HTR. The front-end of flowsheet using sol-gel process. The external sol-gel process is chosen due to simple equipment can anticipate refabrication of U-233 which always contains a few hundred ppm of U-232 and its gamma-emitting daughters, besides yielding smaller waste. The decision to choose external sol-gel process encourages to develop External Gelation Thorium (EGT). In order to get higher density and relatively low compaction pressures (i.e. for advanced LWR) adopted flowsheet EGT is developed to be Sol-Gel Microsphere Pelletization (SGMP). Using the optimal parameters, SGMP become established flowsheet for producing mixed oxide fuel of (U,Th)O 2 for advanced reactor. (author)

Formation of actinides in irradiated HTGR fuel elements

International Nuclear Information System (INIS)

Santos, A.M. dos.

1976-03-01

Actinide nuclide concentrations of 11 spent AVR fuel elements were determined experimentally. The burnup of the spheres varied in the range between 10% and 100% fifa, the Th : U ratio was 5 : 1. The separation procedures for actinide isolation were tested with highly irradiated ThO 2 . Separation and decontamination factors are presented. Actinide nuclide formation can be described by exponential functions of the type ln msub(nuclide) = A + B x % fifa. The empirical factors A and B were calculated performing a least squares analysis. Build-up of 232 U was discussed. According to the experimental results, 232 U is mainly produced from 230 Th, a certain amount (e.g. about 20% at a 10 5 MWd/t burnup) originated from a (n,2n) reaction of 233 U; a formation from 233 Th by a (n,2n) followed by a (n,γ) reaction was not observed. The AVR breeding rate was ascertained to be 0.5. The hazard potential of high activity waste was calculated. After a 1,000 years' storage time, the elements Pa, Am and Cm will no longer influence the total hazard index. Actinide recovery factors were proposed in order to reduce the hazard potential of the waste by an actinide removal in consideration of the reprocessing technology which is available presently. (orig.) [de

Pilot Designed Aircraft Displays in General Aviation: An Exploratory Study and Analysis

Science.gov (United States)

Conaway, Cody R.

From 2001-2011, the General Aviation (GA) fatal accident rate remained unchanged (Duquette & Dorr, 2014) with an overall stagnant accident rate between 2004 and 2013. The leading cause, loss of control in flight (NTSB, 2015b & 2015c) due to pilot inability to recognize approach to stall/spin conditions (NTSB, 2015b & 2016b). In 2013, there were 1,224 GA accidents in the U.S., accounting for 94% of all U.S. aviation accidents and 90% of all U.S. aviation fatalities that year (NTSB, 2015c). Aviation entails multiple challenges for pilots related to task management, procedural errors, perceptual distortions, and cognitive discrepancies. While machine errors in airplanes have continued to decrease over the years, human error still has not (NTSB, 2013). A preliminary analysis of a PC-based, Garmin G1000 flight deck was conducted with 3 professional pilots. Analyses revealed increased task load, opportunities for distraction, confusing perceptual ques, and hindered cognitive performance. Complex usage problems were deeply ingrained in the functionality of the system, forcing pilots to use fallible work arounds, add unnecessary steps, and memorize knob turns or button pushes. Modern computing now has the potential to free GA cockpit designs from knobs, soft keys, or limited display options. Dynamic digital displays might include changes in instrumentation or menu structuring depending on the phase of flight. Airspeed indicators could increase in size to become more salient during landing, simultaneously highlighting pitch angle on Attitude Indicators and automatically decluttering unnecessary information for landing. Likewise, Angle-of-Attack indicators demonstrate a great safety and performance advantage for pilots (Duquette & Dorr, 2014; NTSB, 2015b & 2016b), an instrument typically found in military platforms and now the Icon A5, light-sport aircraft (Icon, 2016). How does the design of pilots' environment---the cockpit---further influence their efficiency and

Genetic distinctiveness of the Herdwick sheep breed and two other locally adapted hill breeds of the UK.

Science.gov (United States)

Bowles, Dianna; Carson, Amanda; Isaac, Peter

2014-01-01

There is considerable interest in locally adapted breeds of livestock as reservoirs of genetic diversity that may provide important fitness traits for future use in agriculture. In marginal areas, these animals contribute to food security and extract value from land unsuitable for other systems of farming. In England, close to 50% of the national sheep flock is farmed on grassland designated as disadvantaged areas for agricultural production. Many of these areas are in the uplands, where some native breeds of sheep continue to be commercially farmed only in highly localised geographical regions to which they are adapted. This study focuses on three of these breeds, selected for their adaptation to near identical environments and their geographical concentration in regions close to one another. Our objective has been to use retrotyping, microsatellites and single nucleotide polymorphisms to explore the origins of the breeds and whether, despite their similar adaptations and proximity, they are genetically distinctive. We find the three breeds each have a surprisingly different pattern of retrovirus insertions into their genomes compared with one another and with other UK breeds. Uniquely, there is a high incidence of the R0 retrotype in the Herdwick population, characteristic of a primitive genome found previously in very few breeds worldwide and none in the UK mainland. The Herdwick and Rough Fells carry two rare retroviral insertion events, common only in Texels, suggesting sheep populations in the northern uplands have a historical association with the original pin-tail sheep of Texel Island. Microsatellite data and analyses of SNPs associated with RXFP2 (horn traits) and PRLR (reproductive performance traits) also distinguished the three breeds. Significantly, an SNP linked to TMEM154, a locus controlling susceptibility to infection by Maedi-Visna, indicated that all three native hill breeds have a lower than average risk of infection to the lentivirus.