Development of AN Active 238UF6 Gas Target

Science.gov (United States)

Eckardt, C.; Enders, J.; Freudenberger, M.; Göök, A.; von Neumann-Cosel, P.; Oberstedt, A.; Oberstedt, S.

2014-09-01

Detailed studies of the fission process, e.g., the search for parity nonconservation (PNC) effects, the energy dependence of fission modes or the population of fission isomers, depend on high quality data, therefore requiring high luminosities. An active gas target containing uranium may overcome the deterioration of energy and angular resolution caused by large solid target thicknesses. A single Frisch-grid ionization chamber has been built to test a mixture of standard counting gases (e.g., argon) with depleted uranium hexafluoride (238UF6), utilizing a triple alpha source to evaluate signal quality and drift velocity. For mass fractions of up to 4 percent of 238U the drift velocity increases with rising UF6 content, while a good signal quality and energy resolution is preserved.

Photoionization mass spectrometry of UF6

International Nuclear Information System (INIS)

Berkowitz, J.

1979-01-01

The photoionization mass spectrum of 238 UF 6 was obtained. At 600 A = 20.66 eV, the relative ionic abundances were as follows: UF 6 + , 1.4; UF 5 + , 100; UF + , 17; UF 3 + , approx. 0.7; UF 2 + , very weak; UF + , very weak; U + , essentially zero. The adiabatic ionization potential for UF 6 was 13.897 +- 0.005 eV. The production of UF 5 + begins at approx. 887 A = 13.98 eV, at which energy the UF 6 + partial cross section abruptly declines and then levels off. This behavior suggests the vague possibility of an isotope effect. The UF 4 + signal begins at approx. 725 A = 17.10 eV, at which energy the UF 5 + signal reaches a plateau value. The UF 5 + photoionization yield curve displays some autoionization structure from its threshold to approx. 750 A

Studies on (2UF4 + H2 = 2UF3 + 2HF) and vapour pressure of UF3

International Nuclear Information System (INIS)

Roy, K.N.; Prasad, R.; Venugopal, V.; Singh, Z.; Sood, D.D.

1982-01-01

Equilibrium constants for 2UF 4 (s) + H 2 (g) = 2UF 3 (s) + 2HF(g) have been measured in the temperature range 967 to 1120 K. An expression is given for the results. The results have been treated by second- and third-law methods to obtain ΔH 0 (298.15 K) and the values are given. The value of ΔS 0 (298.15 K) has been calculated by the second-law method. An expression is given for the vapour pressure of UF 3 (s), measured by the transpiration technique in the range 1229 to 1367 K. The standard enthalpy of vaporization ΔH 0 sub(v) (298.15 K) and the standard entropy of vaporization ΔS 0 sub(v) (298.15 K) have been calculated. The vaporization results have also been used for the calculation of ΔH 0 sub(f)(UF 3 , g, 298.15 K) and ΔS 0 sub(f)(UF 3 ,g, 298.15 K). (author)

Depleted uranium hexafluoride management program : data compilation for the Paducah site

International Nuclear Information System (INIS)

Hartmann, H.

2001-01-01

This report is a compilation of data and analyses for the Paducah site, near Paducah, Kentucky. The data were collected and the analyses were done in support of the U.S. Department of Energy (DOE) 1999 Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride (DOE/EIS-0269). The report describes the affected environment at the Paducah site and summarizes potential environmental impacts that could result from conducting the following depleted uranium hexafluoride (UF 6 ) activities at the site: continued cylinder storage, preparation of cylinders for shipment, conversion, and long-term storage. DOE's preferred alternative is to begin converting the depleted UF 6 inventory as soon as possible to either uranium oxide, uranium metal, or a combination of both, while allowing for use of as much of this inventory as possible

Depleted uranium hexafluoride management program : data compilation for the Portsmouth site

International Nuclear Information System (INIS)

Hartmann, H. M.

2001-01-01

This report is a compilation of data and analyses for the Portsmouth site, near Portsmouth, Ohio. The data were collected and the analyses were done in support of the U.S. Department of Energy (DOE) 1999 Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride (DOE/EIS-0269). The report describes the affected environment at the Portsmouth site and summarizes potential environmental impacts that could result from conducting the following depleted uranium hexafluoride (UF 6 ) management activities at the site: continued cylinder storage, preparation of cylinders for shipment, conversion, and long-term storage. DOE's preferred alternative is to begin converting the depleted UF 6 inventory as soon as possible to either uranium oxide, uranium metal, or a combination of both, while allowing for use of as much of this inventory as possible

A concept of a nonfissile uranium hexafluoride overpack for storage, transport, and processing of corroded cylinders

International Nuclear Information System (INIS)

Pope, R.B.; Cash, J.M.; Singletary, B.H.

1996-01-01

There is a need to develop a means of safely transporting breached 48-in. cylinders containing depleted uranium hexafluoride (UF 6 ) from current storage locations to locations where the contents can be safely removed. There is also a need to provide a method of safely and easily transporting degraded cylinders that no longer meet the US Department of Transportation (DOT) and American National Standards Institute, Inc., (ANSI) requirements for shipments of depleted UF 6 . A study has shown that an overpack can be designed and fabricated to satisfy these needs. The envisioned overpack will handle cylinder models 48G, 48X, and 48Y and will also comply with the ANSI N14.1 and the American Society of Mechanical Engineers (ASME) Sect. 8 requirements

Depleted uranium hexafluoride: The source material for advanced shielding systems

Energy Technology Data Exchange (ETDEWEB)

Quapp, W.J.; Lessing, P.A. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Cooley, C.R. [Department of Technology, Germantown, MD (United States)

1997-02-01

The U.S. Department of Energy (DOE) has a management challenge and financial liability problem in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. DOE is evaluating several options for the disposition of this UF{sub 6}, including continued storage, disposal, and recycle into a product. Based on studies conducted to date, the most feasible recycle option for the depleted uranium is shielding in low-level waste, spent nuclear fuel, or vitrified high-level waste containers. Estimates for the cost of disposal, using existing technologies, range between $3.8 and $11.3 billion depending on factors such as the disposal site and the applicability of the Resource Conservation and Recovery Act (RCRA). Advanced technologies can reduce these costs, but UF{sub 6} disposal still represents large future costs. This paper describes an application for depleted uranium in which depleted uranium hexafluoride is converted into an oxide and then into a heavy aggregate. The heavy uranium aggregate is combined with conventional concrete materials to form an ultra high density concrete, DUCRETE, weighing more than 400 lb/ft{sup 3}. DUCRETE can be used as shielding in spent nuclear fuel/high-level waste casks at a cost comparable to the lower of the disposal cost estimates. Consequently, the case can be made that DUCRETE shielded casks are an alternative to disposal. In this case, a beneficial long term solution is attained for much less than the combined cost of independently providing shielded casks and disposing of the depleted uranium. Furthermore, if disposal is avoided, the political problems associated with selection of a disposal location are also avoided. Other studies have also shown cost benefits for low level waste shielded disposal containers.

Draft Programmatic Environmental Impact Statement for alternative strategies for the long-term management and use of depleted uranium hexafluoride. Volume 1: Main text

International Nuclear Information System (INIS)

1997-12-01

This PEIS assesses the potential impacts of alternative management of alternative management strategies for depleted uranium hexafluoride (UF 6 ) currently stored at three DOE sites: Paducah site near Paducah, Kentucky; Portsmouth site near Portsmouth, Ohio; and K-25 site on the Oak Ridge Reservation, Oak Ridge, Tennessee. The alternatives analyzed in the PEIS include no action, long-term storage as UF 6 , long-term storage as uranium oxide, use as uranium oxide, use as uranium metal, and disposal. The preferred alternative for the long-term management of depleted UF 6 is to use the entire inventory of material

Selection of a management strategy for depleted uranium

International Nuclear Information System (INIS)

Patton, S.; Hanrahan, E.; Bradley, C. Jnr.

1995-01-01

A consequence of the uranium enrichment process is the accumulation of a significant amount of depleted uranium hexafluoride (UF 6 ). Currently, in the United States approximately 560 000 tonnes of the material are stored at three different sites. The US Department of Energy (DOE) has recently initiated a programme to consider alternative strategies for the cost-effective and environmentally safe long-term management of this inventory of depleted UF 6 . The programme involves a technology and engineering assessment of proposed management options (which are: use/reuse, conversion, storage, or disposal) and an analysis of the potential environmental impacts and life-cycle costs of alternative management strategies. The information obtained from the studies will be used by the DOE to select a preferred long-term management strategy. Because of its provisions for considering a wide range of relevant issues and involving the public, this programme has become a model for future DOE materials disposition programmes. This paper presents an overview of the Depleted Uranium Hexafluoride Management Programme. Technical findings of the programme to date are presented, and major issues involved in selecting and implementing a management strategy are discussed. (author)

Adducts of UF5 with SbF5 and structure of UF5 . 2SbF5

International Nuclear Information System (INIS)

Sawodny, W.; Rediess, K.

1980-01-01

Both α-UF 5 and β-UF 5 form only a 1:2 compound UF 5 . 2SbF 5 reacting directly with SbF 5 , from which UF 5 . SbF 5 can be obtained by thermal decomposition. UF 5 . 2SbF 5 crystallizes in the monoclinic space group P2 1 /c with the following lattice constants a = 8.110(4), b = 14.129(6), c = 10.032(6) A and β = 96.97(5) 0 ; Z = 4. An X-ray study shows centrosymmetric four-membered rings of alternating UF 8 and SbF 6 polyhedra connected by other SbF 6 entities. This structure is similar to that of UOF 5 . 2SbF 5 , but the distorted pentagonal-bipyramidal coordination of the U atom found there is increased to a dodecahedral coordination by an additional U-F-Sb bridge, though with a somewaht larger UF distance. (author)

Final programmatic environmental impact statement for alternative strategies for the long-term management and use of depleted uranium hexafluoride. Summary

International Nuclear Information System (INIS)

1999-04-01

This PEIS assesses the potential impacts of alternative management strategies for depleted uranium hexafluoride (UF 6 ) currently stored at three DOE sites: Paducah site near Paducah, Kentucky, Portsmouth site near Portsmouth, Ohio; and K-25 site on the Oak Ridge Reservation, Oak Ridge, Tennessee. The alternatives analyzed in the PEIS include no action, long-term storage as UF 6 , long-term storage as uranium oxide, use as uranium oxide, use as uranium metal, and disposal. DOE's preferred alternative is to begin conversion of the depleted UF 6 inventory as soon as possible, either to uranium oxide, uranium metal, or a combination of both, while allowing for use of as much of this inventory as possible

Draft Programmatic Environmental Impact Statement for alternative strategies for the long-term management and use of depleted uranium hexafluoride. Volume 2: Appendices

International Nuclear Information System (INIS)

1997-12-01

This PEIS assesses the potential impacts of alternative management of alternative management strategies for depleted uranium hexafluoride (UF 6 ) currently stored at three DOE sites: Paducah site near Paducah, Kentucky; Portsmouth site near Portsmouth, Ohio; and K-25 site on the Oak Ridge Reservation, Oak Ridge, Tennessee. The alternatives analyzed in the PEIS include no action, long-term storage as UF 6 , long-term storage as uranium oxide, use as uranium oxide, use as uranium metal, and disposal. The preferred alternative for the long-term management of depleted UF 6 is to use the entire inventory of material. This volume contains the appendices to volume I

Ultra-low field NMR for detection and characterization of 235 UF6

Energy Technology Data Exchange (ETDEWEB)

Espy, Michelle A [Los Alamos National Laboratory; Magnelind, Per E [Los Alamos National Laboratory; Matlashov, Andrei N [Los Alamos National Laboratory; Urbaitis, Algis V [Los Alamos National Laboratory; Volegov, Petr L [Los Alamos National Laboratory

2009-01-01

We have demonstrated the first ultra-low field (ULF) nuclear magnetic resonance measurements of uranium hexafluoride (UF{sub 6}), both depleted and 70% enriched, which is used in the uranium enrichment process. A sensitive non-invasive detection system would have an important role in non-proliferation surveillance. A two-frequency technique was employed to remove the transients induced by rapidly switching off the 50 mT pre-polarization field. A mean transverse relaxation time T{sub 2} of 24 ms was estimated for the un-enriched UF{sub 6} sample measured at a mean temperature of 80 C. Nuclear magnetic resonance at ULF has several advantages including the ability to measure through metal, such as pipes, and simple magnetic field generation hardware. We present here recent data and discuss the potential for non-proliferation monitoring of enrichment and flow velocity.

Analysis of accidental UF6 releases

International Nuclear Information System (INIS)

Fan Yumao; Tan Rui; Gao Qifa

2012-01-01

As interim substance in the nuclear fuel enrichment process, Uranium Hexafluoride (UF 6 ) is widely applied in nuclear processing, enrichment and fuel fabrication plants. Because of its vivid chemical characteristics and special radiological hazard and chemical toxicity, great attention must be paid to accident of UF 6 leakage. The chemical reactions involved in UF 6 release processes were introduced, therewith potential release styles, pathways and characteristics of diffusion were analyzed. The results indicated that the accidental release process of UF 6 is not a simple passive diffusion. So, specific atmospheric diffusion model related to UF 6 releases need be used in order to analyze and evaluate accurately the accidental consequences. (authors)

The ultimate disposition of depleted uranium

Energy Technology Data Exchange (ETDEWEB)

Lemons, T.R. [Uranium Enrichment Organization, Oak Ridge, TN (United States)

1991-12-31

Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

Depleted uranium hexafluoride: Waste or resource?

International Nuclear Information System (INIS)

Schwertz, N.; Zoller, J.; Rosen, R.; Patton, S.; Bradley, C.; Murray, A.

1995-07-01

The US Department of Energy is evaluating technologies for the storage, disposal, or re-use of depleted uranium hexafluoride (UF 6 ). This paper discusses the following options, and provides a technology assessment for each one: (1) conversion to UO 2 for use as mixed oxide duel, (2) conversion to UO 2 to make DUCRETE for a multi-purpose storage container, (3) conversion to depleted uranium metal for use as shielding, (4) conversion to uranium carbide for use as high-temperature gas-cooled reactor (HTGR) fuel. In addition, conversion to U 3 O 8 as an option for long-term storage is discussed

Chemical exchange between UF6 and UF6- ion in anhydrous hydrofluoric acid

International Nuclear Information System (INIS)

Chatelet, J.; Luce, M.; Plurien, P.; Rigny, P.

1975-01-01

The chemical exchange between UF 6 and the UF 6 - ion is of potential interest for the separation of U isotopes. In this paper, results concerning the value of the separation factor and the kinetics of the homogeneous exchange are given [fr

What Caused the Breach? An Examination of Use of Information Technology and Health Data Breaches

Science.gov (United States)

Wikina, Suanu Bliss

2014-01-01

Data breaches arising from theft, loss, unauthorized access/disclosure, improper disclosure, or hacking incidents involving personal health information continue to increase every year. As of September 2013, reported breaches affecting individuals reached close to 27 million since 2009, when compilation of records on breaches began. These breaches, which involved 674 covered entities and 153 business associates, involved computer systems and networks, desktop computers, laptops, paper, e-mail, electronic health records, and removable/portable devices (CDs, USBs, x-ray films, backup tapes, etc.). Even with the increased use of health information technology by health institutions and allied businesses, theft and loss (not hacking) constitute the major types of data breaches encountered. Removable/portable devices, desktop computers, and laptops were the top sources or locations of the breached information, while the top six states—Virginia, Illinois, California, Florida, New York, and Tennessee—in terms of the number of reported breaches accounted for nearly 75 percent of the total individual breaches, 33 percent of breaches in covered entities, and about 30 percent of the total breaches involving business associates. PMID:25593574

What caused the breach? An examination of use of information technology and health data breaches.

Science.gov (United States)

Wikina, Suanu Bliss

2014-01-01

Data breaches arising from theft, loss, unauthorized access/disclosure, improper disclosure, or hacking incidents involving personal health information continue to increase every year. As of September 2013, reported breaches affecting individuals reached close to 27 million since 2009, when compilation of records on breaches began. These breaches, which involved 674 covered entities and 153 business associates, involved computer systems and networks, desktop computers, laptops, paper, e-mail, electronic health records, and removable/portable devices (CDs, USBs, x-ray films, backup tapes, etc.). Even with the increased use of health information technology by health institutions and allied businesses, theft and loss (not hacking) constitute the major types of data breaches encountered. Removable/portable devices, desktop computers, and laptops were the top sources or locations of the breached information, while the top six states-Virginia, Illinois, California, Florida, New York, and Tennessee-in terms of the number of reported breaches accounted for nearly 75 percent of the total individual breaches, 33 percent of breaches in covered entities, and about 30 percent of the total breaches involving business associates.

Data Breach Preparation

Energy Technology Data Exchange (ETDEWEB)

Belangia, David Warren [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-03-13

The Home Depot Data Breach is the second largest data breach on record. It has or will affect up to 56 million debit or credit cards. A trusted vendor account, coupled with the use of a previously unknown variant of malware that allowed the establishment of a foothold, was the entry point into the Home Depot network. Once inside the perimeter, privilege escalation provided an avenue to obtain the desired information. Home Depot did, however, learn some lessons from Target. Home Depot certainly communicated better than Target, procured insurance, and instituted as secure an environment as possible. There are specific measures an institution should undertake to prepare for a data breach, and everyone can learn from this breach. Publicly available information about the Home Depot Data Breach provides insight into the attack, an old malware variant with a new twist.While the malware was modified as to be unrecognizable with tools, it probably should have been detected. There are also concerns with Home Depot’s insurance and the insurance provider’s apparent lack of fully reimbursing Home Depot for their losses. The effect on shareholders and Home Depot’s stock price was short lived. This story is still evolving but provides interesting lessons learned concerning how an organization should prepare for it inevitable breach.

Final programmatic environmental impact statement for alternative strategies for the long-term management and use of depleted uranium hexafluoride. Volume 1: Main text

International Nuclear Information System (INIS)

1999-04-01

This PEIS assesses the potential impacts of alternative management strategies for depleted uranium hexafluoride (UF 6 ) currently stored at three DOE sites: Paducah site near Paducah, Kentucky, Portsmouth site near Portsmouth, Ohio; and K-25 site on the Oak Ridge Reservation, Oak Ridge, Tennessee. The alternatives analyzed in the PEIS include no action, long-term storage as UF 6 , long-term storage as uranium oxide, use as uranium oxide, use as uranium metal, and disposal. DOE's preferred alternative is to begin conversion of the depleted UF 6 inventory as soon as possible, either to uranium oxide, uranium metal, or a combination of both, while allowing for use of as much of this inventory as possible

Optimizing UF Cleaning in UF-SWRO System Using Red Sea Water

KAUST Repository

Bahshwan, Mohanad

2012-07-01

Increasing demand for fresh water in arid and semi-arid areas, similar to the Middle East, pushed for the use of seawater desalination techniques to augment freshwater. Seawater Reverse Osmosis (SWRO) is one of the techniques that have been commonly used due to its cost effectiveness. Recently, the use of Ultrafiltration (UF) was recommended as an effective pretreatment for SWRO membranes, as opposed to conventional methods (i.e. sand filtration). During UF operation, intermittent cleaning is required to remove particles and contaminants from the membrane\\'s surface and pores. The different cleaning steps consume chemicals and portion of the product water, resulting in a decrease in the overall effectiveness of the process and hence an increase in the production cost. This research focused on increasing the plant\\'s efficiency through optimizing the cleaning protocol without jeopardizing the effectiveness of the cleaning process. For that purpose, the design of experiment (DOE) focused on testing different combinations of these cleaning steps while all other parameters (such as filtration flux or backwash flux) remained constant. The only chemical used was NaOCI during the end of each experiment to restore the trans-membrane pressure (TMP) to its original state. Two trains of Dow™ Ultrafiltration SFP-2880 were run in parallel for this study. The first train (named UF1) was kept at the manufacturer\\'s recommended cleaning steps and frequencies, while the second train (named UF2) was varied according to the DOE. The normalized final TMP was compared to the normalized initial TMP to measure the fouling rate of the membrane at the end of each experiment. The research was supported by laboratory analysis to investigate the cause of the error in the data by analyzing water samples collected at different locations. Visual inspection on the results from the control unit showed that the data cannot be reproduced with the current feed water quality. Statistical analysis

Depleted uranium hexafluoride: Waste or resource?

Energy Technology Data Exchange (ETDEWEB)

Schwertz, N.; Zoller, J.; Rosen, R.; Patton, S. [Lawrence Livermore National Lab., CA (United States); Bradley, C. [USDOE Office of Nuclear Energy, Science, Technology, Washington, DC (United States); Murray, A. [SAIC (United States)

1995-07-01

the US Department of Energy is evaluating technologies for the storage, disposal, or re-use of depleted uranium hexafluoride (UF{sub 6}). This paper discusses the following options, and provides a technology assessment for each one: (1) conversion to UO{sub 2} for use as mixed oxide duel, (2) conversion to UO{sub 2} to make DUCRETE for a multi-purpose storage container, (3) conversion to depleted uranium metal for use as shielding, (4) conversion to uranium carbide for use as high-temperature gas-cooled reactor (HTGR) fuel. In addition, conversion to U{sub 3}O{sub 8} as an option for long-term storage is discussed.

Final programmatic environmental impact statement for alternative strategies for the long-term management and use of depleted uranium hexafluoride. Volume 2: Appendices

International Nuclear Information System (INIS)

1999-04-01

This PEIS assesses the potential impacts of alternative management strategies for depleted uranium hexafluoride (UF 6 ) currently stored at three DOE sites: Paducah site near Paducah, Kentucky, Portsmouth site near Portsmouth, Ohio; and K-25 site on the Oak Ridge Reservation, Oak Ridge, Tennessee. The alternatives analyzed in the PEIS include no action, long-term storage as UF 6 , long-term storage as uranium oxide, use as uranium oxide, use as uranium metal, and disposal. DOE's preferred alternative is to begin conversion of the depleted UF 6 inventory as soon as possible, either to uranium oxide, uranium metal, or a combination of both, while allowing for use of as much of this inventory as possible. This volume contains Appendices A--O

Intermittent ephemeral river-breaching

Science.gov (United States)

Reniers, A. J.; MacMahan, J. H.; Gallagher, E. L.; Shanks, A.; Morgan, S.; Jarvis, M.; Thornton, E. B.; Brown, J.; Fujimura, A.

2012-12-01

In the summer of 2011 we performed a field experiment in Carmel River State Beach, CA, at a time when the intermittent natural breaching of the ephemeral Carmel River occurred due to an unusually rainy period prior to the experiment associated with El Nino. At this time the river would fill the lagoon over the period of a number of days after which a breach would occur. This allowed us to document a number of breaches with unique pre- and post-breach topographic surveys, accompanying ocean and lagoon water elevations as well as extremely high flow (4m/s) velocities in the river mouth during the breaching event. The topographic surveys were obtained with a GPS-equipped backpack mounted on a walking human and show the evolution of the river breaching with a gradually widening and deepening river channel that cuts through the pre-existing beach and berm. The beach face is qualified as a steep with an average beach slope of 1:10 with significant reflection of the incident waves (MacMahan et al., 2012). The wave directions are generally shore normal as the waves refract over the deep canyon that is located offshore of the beach. The tide is mixed semi-diurnal with a range on the order of one meter. Breaching typically occurred during the low-low tide. Grain size is highly variable along the beach with layers of alternating fine and coarse material that could clearly be observed as the river exit channel was cutting through the beach. Large rocky outcroppings buried under the beach sand are also present along certain stretches of the beach controlling the depth of the breaching channel. The changes in the water level measured within the lagoon and the ocean side allows for an estimate of the volume flux associated with the breach as function of morphology, tidal elevation and wave conditions as well as an assessment of the conditions and mechanisms of breach closure, which occurred on the time scale of O(0.5 days). Exploratory model simulations will be presented at the

Technical documentation of HGSYSTEM/UF6 model

International Nuclear Information System (INIS)

Hanna, S.R.; Chang, J.C.; Zhang, J.X.

1996-01-01

MMES has been directed to upgrade the safety analyses for the gaseous diffusion plants at Paducah KY and Piketon OH. These will require assessment of consequences of accidental releases of UF 6 to the atmosphere at these plants. The HGSYSTEM model has been chosen as the basis for evaluating UF 6 releases; it includes dispersion algorithms for dense gases and treats the chemistry and thermodynamics of HF, a major product of the reaction of UF 6 with water vapor in air. Objective of this project was to incorporate additional capability into HGSYSTEM: UF 6 chemistry and thermodynamics, plume lift-off algorithms, and wet and dry deposition. The HGSYSTEM modules are discussed. The hybrid HGSYSTEM/UF 6 model has been evaluated in three ways

38 CFR 75.113 - Data breach.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Data breach. 75.113 Section 75.113 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) INFORMATION SECURITY MATTERS Data Breaches § 75.113 Data breach. Consistent with the definition of data breach in § 75.112 of this subpart, a data breach...

Applying Mechanistic Dam Breach Models to Historic Levee Breaches

OpenAIRE

Risher Paul; Gibson Stanford

2016-01-01

Hurricane Katrina elevated levee risk in the US national consciousness, motivating agencies to assess and improve their levee risk assessment methodology. Accurate computation of the flood flow magnitude and timing associated with a levee breach remains one of the most difficult and uncertain components of levee risk analysis. Contemporary methods are largely empirical and approximate, introducing substantial uncertainty to the damage and life loss models. Levee breach progressions are often ...

Sensitometric characteristics of UF-4, UF-5, and UFSh-O films in the quantum-energy range of 5-30 keV

International Nuclear Information System (INIS)

Datsko, I.M.; Slabkovskaya, M.A.; Sokolov, A.S.; Uvarova, N.V.; Sheromov, M.A.

1987-01-01

The sensitivity, gamma, and transmission of UF-4, UF-5, and UFSh-O for quanta with energies of 5-30 keV extracted from a beam of synchrotron radiation are measured. UFSh-O photographic film is more sensitive by a factor of 1.5-2 than are the UF-4 and UF-5 films. The gamma of all the films is greatly dependent on the quantum energy

Investigation of UF6 behavior in a fire

International Nuclear Information System (INIS)

Williams, W.R.

1988-01-01

Reactions between UF 6 and combustible gases and the potential for UF 6 -filled cylinders to rupture when exposed to fire are addressed. Although the absence of kinetic data prevents specific identification and quantification of the chemical species formed, potential reaction products resulting from the release of UF 6 into a fire include UF 4 , UO 2 F 2 , HF, C, CF 4 ,COF 2 , and short chain, fluorinated or partially fluorinated hydrocarbons. Such a release adds energy to a fire relative to normal combustion reactions. Time intervals to an assumed point of rupture for UF 6 -filled cylinders exposed to fire are estimated conservatively. Several related studies are also summarized, including a test series in which small UF 6 -filled cylinders were immersed in fire resulting in valve failures and explosive ruptures. It is concluded that all sizes of UF 6 cylinders currently in use may rupture within 30 minutes when totally immersed in a fire. For cylinders adjacent to fires, rupture of the larger cylinders appears much less likely

Breached fuel pin contamination from Run Beyond Cladding Breach (RBCB) tests in EBR-II

International Nuclear Information System (INIS)

Colburn, R.P.; Strain, R.V.; Lambert, J.D.B.; Ukai, S.; Shibahara, I.

1988-09-01

Studies indicate there may be a large economic incentive to permit some continued reactor operation with breached fuel pin cladding. A major concern for this type of operation is the potential spread of contamination in the primary coolant system and its impact on plant maintenance. A study of the release and transport of contamination from naturally breached mixed oxide Liquid Metal Reactor (LMR) fuel pins was performed as part of the US Department of Energy/Power Reactor and Nuclear Fuel Development Corporation (DOE/PNC) Run Beyond Cladding Breach (RBCB) Program at EBR-II. The measurements were made using the Breached Fuel Test Facility (BFTF) at EBR-II with replaceable deposition samplers located approximately 1.5 meters from the breached fuel test assemblies. The effluent from the test assemblies containing the breached fuel pins was routed up through the samplers and past dedicated instrumentation in the BFTF before mixing with the main coolant flow stream. This paper discusses the first three contamination tests in this program. 2 refs., 5 figs., 2 tabs

Analysis of an indirect neutron signature for enhanced UF_6 cylinder verification

International Nuclear Information System (INIS)

Kulisek, J.A.; McDonald, B.S.; Smith, L.E.; Zalavadia, M.A.; Webster, J.B.

2017-01-01

The International Atomic Energy Agency (IAEA) currently uses handheld gamma-ray spectrometers combined with ultrasonic wall-thickness gauges to verify the declared enrichment of uranium hexafluoride (UF_6) cylinders. The current method provides relatively low accuracy for the assay of "2"3"5U enrichment, especially for natural and depleted UF_6. Furthermore, the current method provides no capability to assay the absolute mass of "2"3"5U in the cylinder due to the localized instrument geometry and limited penetration of the 186-keV gamma-ray signature from "2"3"5U. Also, the current verification process is a time-consuming component of on-site inspections at uranium enrichment plants. Toward the goal of a more-capable cylinder assay method, the Pacific Northwest National Laboratory has developed the hybrid enrichment verification array (HEVA). HEVA measures both the traditional 186-keV direct signature and a non-traditional, high-energy neutron-induced signature (HEVA_N_T). HEVA_N_T enables full-volume assay of UF_6 cylinders by exploiting the relatively larger mean free paths of the neutrons emitted from the UF_6. In this work, Monte Carlo modeling is used as the basis for characterizing HEVA_N_T in terms of the individual contributions to HEVA_N_T from nuclides and hardware components. Monte Carlo modeling is also used to quantify the intrinsic efficiency of HEVA for neutron detection in a cylinder-assay geometry. Modeling predictions are validated against neutron-induced gamma-ray spectra from laboratory measurements and a relatively large population of Type 30B cylinders spanning a range of enrichments. Implications of the analysis and findings on the viability of HEVA for cylinder verification are discussed, such as the resistance of the HEVA_N_T signature to manipulation by the nearby placement of neutron-conversion materials.

UF{sub 6} pressure excursions during cylinder heating

Energy Technology Data Exchange (ETDEWEB)

Brown, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

As liquid UF{sub 6} inside a cylinder changes from a liquid to a solid, it forms a porous solid which occupies approximately the same volume as that of the liquid before cooling. Simultaneously as the liquid cools, UF{sub 6} vapor in the cylinder ullage above the liquid desublimes on the upper region of the inner cylinder wall. This solid is a dense, glass-like material which can accumulate to a significant thickness. The thickness of the solid coating on the upper cylinder wall and directly behind the cylinder valve area will vary depending on the conditions during the cooling stage. The amount of time lapsed between UF{sub 6} solidification and UF{sub 6} liquefaction can also affect the UF{sub 6} coating. This is due to the daily ambient heat cycle causing the coating to sublime from the cylinder wall to cooler areas, thus decreasing the thickness. Structural weakening of the dense UF{sub 6} layer also occurs due to cylinder transport vibration and thermal expansion. During cylinder heating, the UF{sub 6} nearest the cylinder wall will liquefy first. As the solid coating behind the cylinder valve begins to liquefy, it results in increased pressure depending upon the available volume for expansion. At the Paducah Gaseous Diffusion Plant (PGDP) during the liquefaction of the UF{sub 6} in cylinders in the UF{sub 6} feed and sampling autoclaves, this pressure increase has resulted in the activation of the systems rupture discs which are rated at 100 pounds per square inch differential.

235U enrichment determination on UF6 cylinders with CZT detectors

Science.gov (United States)

Berndt, Reinhard; Mortreau, Patricia

2018-04-01

Measurements of uranium enrichment in UF6 transit cylinders are an important nuclear safeguards verification task, which is performed using a non-destructive assay method, the traditional enrichment meter, which involves measuring the count rate of the 186 keV gamma ray. This provides a direct measure of the 235U enrichment. Measurements are typically performed using either high-resolution detectors (Germanium) with e-cooling and battery operation, or portable devices equipped with low resolution detectors (NaI). Despite good results being achieved when measuring Low Enriched Uranium in 30B type cylinders and natural uranium in 48Y type containers using both detector systems, there are situations, which preclude the use of one or both of these systems. The focus of this work is to address some of the recognized limitations in relation to the current use of the above detector systems by considering the feasibility of an inspection instrument for 235U enrichment measurements on UF6 cylinders using the compact and light Cadmium Zinc Telluride (CZT) detectors. In the present work, test measurements were carried out, under field conditions and on full-size objects, with different CZT detectors, in particular for situations where existing systems cannot be used e.g. for stacks of 48Y type containers with depleted uranium. The main result of this study shows that the CZT detectors, actually a cluster of four μCZT1500 micro spectrometers provide as good results as the germanium detector in the ORTEC Micro-trans SPEC HPGe Portable spectrometer, and most importantly in particular for natural and depleted uranium in 48Y cylinders.

Analysis of an indirect neutron signature for enhanced UF{sub 6} cylinder verification

Energy Technology Data Exchange (ETDEWEB)

Kulisek, J.A., E-mail: Jonathan.Kulisek@pnnl.gov; McDonald, B.S.; Smith, L.E.; Zalavadia, M.A.; Webster, J.B.

2017-02-21

The International Atomic Energy Agency (IAEA) currently uses handheld gamma-ray spectrometers combined with ultrasonic wall-thickness gauges to verify the declared enrichment of uranium hexafluoride (UF{sub 6}) cylinders. The current method provides relatively low accuracy for the assay of {sup 235}U enrichment, especially for natural and depleted UF{sub 6}. Furthermore, the current method provides no capability to assay the absolute mass of {sup 235}U in the cylinder due to the localized instrument geometry and limited penetration of the 186-keV gamma-ray signature from {sup 235}U. Also, the current verification process is a time-consuming component of on-site inspections at uranium enrichment plants. Toward the goal of a more-capable cylinder assay method, the Pacific Northwest National Laboratory has developed the hybrid enrichment verification array (HEVA). HEVA measures both the traditional 186-keV direct signature and a non-traditional, high-energy neutron-induced signature (HEVA{sub NT}). HEVA{sub NT} enables full-volume assay of UF{sub 6} cylinders by exploiting the relatively larger mean free paths of the neutrons emitted from the UF{sub 6}. In this work, Monte Carlo modeling is used as the basis for characterizing HEVA{sub NT} in terms of the individual contributions to HEVA{sub NT} from nuclides and hardware components. Monte Carlo modeling is also used to quantify the intrinsic efficiency of HEVA for neutron detection in a cylinder-assay geometry. Modeling predictions are validated against neutron-induced gamma-ray spectra from laboratory measurements and a relatively large population of Type 30B cylinders spanning a range of enrichments. Implications of the analysis and findings on the viability of HEVA for cylinder verification are discussed, such as the resistance of the HEVA{sub NT} signature to manipulation by the nearby placement of neutron-conversion materials.

Pilot plant UF6 to UF4 test operations report

International Nuclear Information System (INIS)

Bicha, W.J.; Fallings, M.; Gilbert, D.D.; Koch, G.E.; Levine, P.J.; McLaughlin, D.F.; Nuhfer, K.R.; Reese, J.C.

1987-02-01

The FMPC site includes a plant designed for the reduction of uranium hexafluoride (UF 6 ) to uranium tetrafluoride (UF 4 ). Limited operation of the upgraded reduction facility began in August 1984 and continued through January 19, 1986. A reaction vessel ruptured on that date causing the plant operation to be shut down. The DOE conducted a Class B investigation with the findings of the investigation board issued in preliminary form in May 1986 and as a final recommendation in July 1986. A two-phase restart of the plant was planned and implemented. Phase I included implementing safety system modifications, changing reaction vessel temperature control strategy, and operating the reduction plant under an 8-week controlled test. The results of the test period are the subject of this report. 41 figs., 11 tabs

The process research of drying UF4 by microwave

International Nuclear Information System (INIS)

Wen Guo; Wang Yunbo; Liu Long

2010-01-01

This paper make use of microwave to dry UF 4 filter cake, the aim is desorbed adsorption water. The research focus on such process conditions, boat material, thickness of filter cake, drying time, setting temperature, heating power and so on. the research of desorption crystal water of UF 4 that dried by microwave in fixed bed .When UF 4 drying by microwave and claiming by fixed bed, the qualified UF 4 powder is prepared. The research is shown that microwave can desorbs adsorption water which contain in UF 4 filter cake. There is a stable water contents in UF 4 after drying, and the sum of two members is less. After drying by microwave and claiming by fixed bed, the contents of water, UO 2 and UO 2 F 2 are all according to the quality standard. (authors)

Uranium isotope fractionation resulting from UF6 vapor distillation from containers

International Nuclear Information System (INIS)

Hedge, W.D.; Turner, C.M.

1985-01-01

This empirical study for possible isotopic fractionation due to UF 6 vapor distillation from valved containers was performed to determine the effects of repeated vapor sampling. Four different experiments were performed, each of which varied by the method of measuring the isotopic contents and/or by the difference in temperature gradients as follows: The ratio of the parent UF 6 to the desublimed UF 6 collected at liquid nitrogen temperature and homogenized was measured by sampling the containers. The ratio of the parent UF 6 to the desublimed UF 6 collected at liquid nitrogen temperature and homogenized was measured by direct comparison to each other without subsampling. The ratio of the parent UF 6 to the desublimed UF 6 collected at liquid nitrogen and ice-water temperatures and homogenized was measured by indirect comparison to a common UF 6 reference material without subsampling. The ratio of the parent UF 6 to the desublimed UF 6 collected at liquid nitrogen temperature without homogenizing was measured by indirect comparison to a common UF 6 reference. Gas-phase, relative mass spectrometry was used for all isotopic measurements. Results of the study indicate that fractionation does occur. The U-235 isotope becomes more enriched in the parent container as the UF 6 is vaporized from it and desublimed into the receiving cylinder; i.e., the vaporized fraction is enriched in the U-238 isotope. The degree of fractionation indicates that the separation is due to the U-238 isotope of UF 6 having a higher vapor pressure than the U-235 isotope of UF 6 . 3 refs., 4 figs., 4 tabs

UF{sub 6} cylinder fire test

Energy Technology Data Exchange (ETDEWEB)

Park, S.H. [Oak Ridge K-25 Site, Oak Ridge, TN (United States)

1991-12-31

With the increasing number of nuclear reactors for power generation, there is a comparable increase in the amount of UF{sub 6} being transported. Likewise, the probability of having an accident involving UF{sub 6}-filled cylinders also increases. Accident scenarios which have been difficult to assess are those involving a filled UF{sub 6} cylinder subjected to fire. A study is underway at the Oak Ridge K-25 Site, as part of the US DOE Enrichment Program, to provide empirical data and a computer model that can be used to evaluate various cylinder-in-fire scenarios. It is expected that the results will provide information leading to better handling of possible fire accidents as well as show whether changes should be made to provide different physical protection during shipment. The computer model being developed will be capable of predicting the rupture of various cylinder sizes and designs as well as the amount of UF{sub 6}, its distribution in the cylinder, and the conditions of the fire.

13 CFR 115.69 - Imminent Breach.

Science.gov (United States)

2010-01-01

... an Imminent Breach of the terms of a Contract covered by an SBA guaranteed bond. The PSB Surety does... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Imminent Breach. 115.69 Section... Surety Bond (PSB) Guarantees § 115.69 Imminent Breach. (a) No prior approval requirement. SBA will...

Privacy Breach Analysis in Social Networks

Science.gov (United States)

Nagle, Frank

This chapter addresses various aspects of analyzing privacy breaches in social networks. We first review literature that defines three types of privacy breaches in social networks: interactive, active, and passive. We then survey the various network anonymization schemes that have been constructed to address these privacy breaches. After exploring these breaches and anonymization schemes, we evaluate a measure for determining the level of anonymity inherent in a network graph based on its topological structure. Finally, we close by emphasizing the difficulty of anonymizing social network data while maintaining usability for research purposes and offering areas for future work.

Preventing a data breach from becoming a disaster.

Science.gov (United States)

Goldberg, Ed

2013-01-01

Organisations have traditionally dealt with data breaches by investing in protective measures without a great deal of attention to mitigation of breach consequences and response. Conversely, business continuity (BC) planning has traditionally focused on mitigating disasters, not on preventing them. From a BC planning perspective, organisations need to assume that a data breach is inevitable and plan accordingly. The spate of data breaches in these past few years hit many organisations that were well protected. Those that suffered disastrous consequences as a result of a data breach lacked effective mitigation and response, not protection. The complexity and speed of an effective data breach response require that detailed planning takes place in advance of a breach.

Selection of a management strategy for depleted uranium hexafluoride

International Nuclear Information System (INIS)

Patton, S.E.; Hanrahan, E.J.; Bradley, C.E.

1995-01-01

A consequence of the uranium enrichment process used in the United States (US) is the accumulation of a significant amount of depleted uranium hexafluoride (UF 6 ). Currently, approximately 560,000 metric tons of the material are stored at three different sites. The US Department of Energy (DOE) has recently initiated a program to consider alternative strategies for the cost-effective and environmentally safe long-term management of this inventory of depleted UF 6 . The program involves a technology and engineering assessment of proposed management options (use/reuse, conversion, storage, or disposal) and an analysis of the potential environmental impacts and life-cycle costs of alternative management strategies. The information obtained from the studies will be used by the DOE to select a preferred long-term management strategy. The selection and implementation of a management strategy will involve consideration of a number of important issues such as environmental, health, and safety effects; the balancing of risks versus costs in a context of reduced government spending; socioeconomic implications, including effects on the domestic and international uranium industry; the technical status of proposed uses or technologies; and public involvement in the decision making process. Because of its provisions for considering a wide range of relevant issues and involving the public, this program has become a model for future DOE materials disposition programs. This paper presents an overview of the Depleted Uranium Hexafluoride Management Program. Technical findings of the program to date are presented, and major issues involved in selecting and implementing a management strategy are discussed

Psychological contract breach among allied health professionals.

Science.gov (United States)

Rodwell, John; Gulyas, Andre

2015-01-01

Allied health professionals are vital for effective healthcare yet there are continuing shortages of these employees. Building on work with other healthcare professionals, the purpose of this paper is to investigate the influence of psychological contract (PC) breach and types of organisational justice on variables important to retention among allied health professionals: mental health and organisational commitment. The potential effects of justice on the negative outcomes of breach were examined. Multiple regressions analysed data from 113 allied health professionals working in a medium-large Australian healthcare organisation. The main negative impacts on respondents' mental health and commitment were from high PC breach, low procedural and distributive justice and less respectful treatment from organisational representatives. The interaction between procedural justice and breach illustrates that breach may be forgivable if processes are fair. Surprisingly, a betrayal or "aggravated breach effect" may occur after a breach when interpersonal justice is high. Further, negative affectivity was negatively related to respondents' mental health (affective outcomes) but not commitment (work-related attitude). Healthcare organisations should ensure the fairness of decisions and avoid breaking promises within their control. If promises cannot reasonably be kept, transparency of processes behind the breach may allow allied health professionals to understand that the organisation did not purposefully fail to fulfil expectations. This study offers insights into how breach and four types of justice interact to influence employee mental health and work attitudes among allied health professionals.

Seasonal breaching of coastal barriers

NARCIS (Netherlands)

Tuan, Thieu Quang

2007-01-01

Natural or unintended breaching can be catastrophic, causing loss of human lives and damage to infrastructures, buildings and natural habitats. Quantitative understand-ing of coastal barrier breaching is therefore of great importance to vulnerability as-sessment of protection works as well as to

Method and apparatus for measuring enrichment of UF6

Science.gov (United States)

Hill, Thomas Roy [Santa Fe, NM; Ianakiev, Kiril Dimitrov [Los Alamos, NM

2011-06-07

A system and method are disclosed for determining the enrichment of .sup.235U in Uranium Hexafluoride (UF6) utilizing synthesized X-rays which are directed at a container test zone containing a sample of UF6. A detector placed behind the container test zone then detects and counts the X-rays which pass through the container and the UF6. In order to determine the portion of the attenuation due to the UF6 gas alone, this count rate may then be compared to a calibration count rate of X-rays passing through a calibration test zone which contains a vacuum, the test zone having experienced substantially similar environmental conditions as the actual test zone. Alternatively, X-rays of two differing energy levels may be alternately directed at the container, where either the container or the UF6 has a high sensitivity to the difference in the energy levels, and the other having a low sensitivity.

HEU to LEU Conversion and Blending Facility: UF6 blending alternative to produce LEU UF6 for commercial use

International Nuclear Information System (INIS)

1995-09-01

US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials; the nuclear material will be converted to a form more proliferation- resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. Five technologies for blending HEU will be assessed; blending as UF 6 to produce a UF 6 product for commercial use is one of them. This document provides data to be used in the environmental impact analysis for the UF 6 blending HEU disposition option. Resource needs, employment needs, waste and emissions from plant, hazards, accident scenarios, and intersite transportation are discussed

FTIR spectroscopy of UF6 clustering in a supersonic Laval nozzle

International Nuclear Information System (INIS)

Tanimura, Shinobu; Okada, Yoshiki; Takeuchi, Kazuo

1996-01-01

The clustering of UF 6 seeded in Ar was observed in a continuous supersonic Laval nozzle flow. The onset conditions for UF 6 clustering were investigated by measuring the FTIR spectra of UF 6 monomer and clusters in the nozzle. The onset conditions for the clustering, temperature, density of UF 6 (or partial pressure), and cooling rate, were determined. The onset temperature determined here was higher by 40-50 K than that determined by a light-scattering method. The frequency shift of the main peak of the UF 6 clusters from the monomer peak was about -17 cm -1 , which was smaller than the shift of the crystalline UF 6 by about 11 cm -1 . The increase in temperature caused by the heat of condensation and the change of the spectra of UF 6 clusters with the growth after the onset were also observed. It was shown that the clustering rate due to the collision between the monomer and cluster is much higher than that due to the collision between the monomers. 19 refs., 9 figs

User Compensation as a Data Breach Recovery Action: An Investigation of the Sony PlayStation Network Breach.

OpenAIRE

Venkatesh, Viswanath

2017-01-01

Drawing on expectation confirmation research, we develop hypotheses regarding the effect of compensation on key customer outcomes following a major data breach and consequent service recovery effort. Data were collected in a longitudinal field study of Sony customers during their data breach in 2011. A total of 144 customers participated in the two-phase data collection that began when the breach was announced and concluded after reparations were made. Using polynomial modeling an...

Data breaches. Final rule.

Science.gov (United States)

2008-04-11

This document adopts, without change, the interim final rule that was published in the Federal Register on June 22, 2007, addressing data breaches of sensitive personal information that is processed or maintained by the Department of Veterans Affairs (VA). This final rule implements certain provisions of the Veterans Benefits, Health Care, and Information Technology Act of 2006. The regulations prescribe the mechanisms for taking action in response to a data breach of sensitive personal information.

Review of potential models for UF6 dispersion

International Nuclear Information System (INIS)

Sykes, R.I.; Lewellen, W.S.

1992-07-01

A survey of existing atmospheric dispersion models has been conducted to determine the most appropriate basis for the development of a model for predicting the consequences of an accidental UF 6 release. The model is required for safety analysis studies and should therefore be computationally efficient. The release of UF 6 involves a number of physical phenomena which make the situation more complicated than passive dispersion of a trace gas. The safety analysis must consider the density variations in the UF 6 cloud, which can be heavier or lighter than the ambient air. The release also involves rapid chemical reactions and associated heat release, which must be modeled. Other Department of Energy storage facilities require a dense gas prediction capability, so the model must be sufficiently general for use with a variety of release scenarios. The special problems associated with UF 6 make it unique, so there are very few models with existing capability for the problem. There are, however, a large number of dense gas dispersion models, some with relevant chemical reaction modeling, that could potentially form the basis of an advanced UF 6 model. We have examined a large selection of possible candidates, and selected 5 models for detailed consideration

Douglas County Dam Breach Inundation Areas

Data.gov (United States)

Kansas Data Access and Support Center — Dam breach analysis provides a prediction of the extent and timing of flooding from a catastrophic breach of the dams. These results are sufficient for developing...

Metamorphosis: Phases of UF{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Dyer, R.H. [Department of Energy, Oak Ridge, TN (United States)

1991-12-31

A 15-minute videotape is presented. The subject matter is 150 grams of UF{sub 6} sealed in a glass tube. Close-up views show the UF{sub 6} as phase changes are effected by the addition or removal of heat from the closed system. The solid-to-liquid transition is shown as heat is added, both slowly and rapidly. The solid phases which result from freezing and from desublimation are contrasted. In the solid state, uranium hexafluoride is a nearly-white, dense crystalline solid. The appearance of this solid depends on whether it is formed by freezing from the liquid or by desublimation from the vapor phase. If frozen from the liquid, the solid particles take the form of irregularly shaped coarse grains, while the solid product of desublimation tends to be a rather formless mass without individually distinguishable particles. The changes in state are presented in terms of the UF{sub 6} phase diagram.

Yield, utilization, storage and ultimate storage of depleted uranium

International Nuclear Information System (INIS)

Aumueller, L.; Hermann, J.

1977-11-01

More than 80% of the uranium leaving uranium enrichment plants is depleted to a residual content of about 0,25% U 235. Due to the present ineconomical further depletion to the technically possible residual content of 0,1% U 235, the so-called 'tails' are first of all stored. The quantity of stored depleted uranium in the FRG should be about 100.000 t by the year 2000. It represents a strategic reserve for future energy supply regardless of profitableness. The study analysis the conceivable possible uses for the tails quantity considered. These are, besides further depletion whose profitableness is considered, also the use as breeder material in breeder reactors and the use in the non-nuclear field. The main part of the study deals with the various storage possibilities of the depleted uranium in oxidic or fluoride form. A comparison of costs of alternative storage concepts showed a clear advantage for the storage of UF 6 in 48 inch containers already in use. The conceivable accidents in storing are analyzed and measures to reduce the consequences are discussed. Finally, the problems of ultimate storage for the remaining waste after further depletion or use are investigated and the costs arising here are also estimated. (RB) [de

Synthesis and characterization of a new uranium(V) compound: H3O+UF6-

International Nuclear Information System (INIS)

Masson, J.P.; Desmoulin, J.P.; Charpin, P.; Bougon, R.

1976-01-01

The reaction of equimolar amounts of UF 5 and H 2 O in hydrogen fluoride results in the partial dissolution of UF 5 , yielding a blue-green solution from which the new salt oxonium hexafluorouranate(V)(H 3 O + UF 6 - ) could be isolated as a green crystalline solid. Calorimetric measurements showed H 3 O + UF 6 - to decompose at about 68 0 C and its heat of formation to be equal to -628 +- 2 kcal mol. Its ionic nature in the solid state and in HF solutions was demonstrated from vibrational and electronic spectra. The electronic spectrum is closely similar to those of LiUF 6 , NaUF 6 , and CsUF 6 and differs from those of RbUF 6 and KUF 6 . This adduct shows a strong ESR signal, with g = -0.78 +- 0.10, characteristic of UF 6 - salts. Based on its x-ray powder diffraction pattern, H 3 O + UF 6 - is cubic with a = 5.2229 +- 0.0005 A

Breaching the Castle Walls: Hyaluronan-Depletion as a Therapeutic Approach to Cancer Therapy

Directory of Open Access Journals (Sweden)

H Michael eShepard

2015-08-01

Full Text Available Hyaluronan (HA has many functions in the extracellular milieu of normal and diseased tissues. Disease-associated HA accumulation has been shown to predict a worsened prognosis in cancer patients, with tumors having a high extracellular HA content (HA-high being more aggressive than their HA-low counterparts. HA-high tumor aggressiveness is derived from the specialized biomechanical and molecular properties of the HA-based assembly of HA binding proteins and the growth-promoting factors that accumulate in it. Biophysical characteristics of an HA-high tumor microenvironment include high tumor interstitial pressure, compression of tumor vasculature, and resulting tumor hypoxia. Within the tumor cell membrane, HA receptors, primarily CD44 and RHAMM, anchor the HA-high extracellular network. HA-CD44 association on the tumor cell surface enhances receptor tyrosine kinase activity to drive tumor progression and treatment resistance. Together, malignant cells in this HA-high matrix may evolve dependency on it for growth. This yields the hypothesis that depleting HA in HA-high tumors may be associated with a therapeutic benefit. A pegylated form of recombinant human hyaluronidase PH20 (PEGPH20 has been deployed as a potential cancer therapeutic in HA-high tumors. PEGPH20 can collapse this matrix by degrading the HA-assembled tumor extracellular framework, leading to tumor growth inhibition, preferentially in HA-high tumors. Enzymatic depletion of HA by PEGPH20 results in re-expansion of the tumor vasculature, reduction in tumor hypoxia, and increased penetration of therapeutic molecules into the tumor. Finally, HA depletion results in reduced signaling via CD44/RHAMM. Taken together, HA-depletion strategies accomplish their antitumor effects by multiple mechanisms that include targeting both biophysical and molecular signaling pathways. Ongoing clinical trials are examining the potential of PEGPH20 in combination with partner therapeutics in several

Data breach locations, types, and associated characteristics among US hospitals.

Science.gov (United States)

Gabriel, Meghan Hufstader; Noblin, Alice; Rutherford, Ashley; Walden, Amanda; Cortelyou-Ward, Kendall

2018-02-01

The objectives of this study were to describe the locations in hospitals where data are breached, the types of breaches that occur most often at hospitals, and hospital characteristics, including health information technology (IT) sophistication and biometric security capabilities, that may be predicting factors of large data breaches that affect 500 or more patients. The Office of Civil Rights breach data from healthcare providers regarding breaches that affected 500 or more individuals from 2009 to 2016 were linked with hospital characteristics from the Health Information Management Systems Society and the American Hospital Association Health IT Supplement databases. Descriptive statistics were used to characterize hospitals with and without breaches, data breach type, and location/mode of data breaches in hospitals. Multivariate logistic regression analysis explored hospital characteristics that were predicting factors of a data breach affecting at least 500 patients, including area characteristics, region, health system membership, size, type, biometric security use, health IT sophistication, and ownership. Of all types of healthcare providers, hospitals accounted for approximately one-third of all data breaches and hospital breaches affected the largest number of individuals. Paper and films were the most frequent location of breached data, occurring in 65 hospitals during the study period, whereas network servers were the least common location but their breaches affected the most patients overall. Adjusted multivariate results showed significant associations among data breach occurrences and some hospital characteristics, including type and size, but not others, including health IT sophistication or biometric use for security. Hospitals should conduct routine audits to allow them to see their vulnerabilities before a breach occurs. Additionally, information security systems should be implemented concurrently with health information technologies. Improving

TENERIFE program: high temperature experiments on A 4 tons UF6 container

International Nuclear Information System (INIS)

Casselman, C.; Duret, B.; Seiler, J.M.; Ringot, C.; Warniez, P.; Wataru, M.; Shiomi, S.; Ozaki, S.; Yamakawa, H.

1993-01-01

To know the input of the future thermo-mechanical code, we have to get a better understanding of the thermo-physical evolution of the UF 6 which pressurizes the container. This evolution is function of: a) the heat transfer rate from the fire to the container b) the UF 6 behaviour in the container. These tests are essentially analytical at simulated fire temperatures of between 800 and 1000degC. They use a representative mass of UF 6 (around 4 tons). The tests will not seek to rupture the test container which has a diameter equal to the 48Y container, but shorter length. These tests carried out in realistic conditions (typical thermal gradient at the wall, characteristic period for UF 6 internal mass transfer) should make possible to improve knowledge of two fundamental phenomena: 1) vaporization of UF 6 on contact with the heated wall (around 400degC), a phenomenon which controls the container internal pressurization kinetic, 2) the equivalent conductivity of solid UF 6 , a phenomenon which is linked to the heat transfer by UF 6 vaporization-condensation through the solid's porosities and which depends on the diameter of the container. In addition, they will allow the influence of other parameters to be studied, such as UF 6 container filling mode or the mechanical characteristics of the container material. A UF 6 container fitted with instruments (wall temperature, UF 6 temperature, pressure) is heated by a rapid heat transient in a radiating furnace where the temperature and thermal power supplied can be measured. The test continues until pre-established thresholds have been reached: 1) strain threshold measured on the container surface (strain gauges positioned on the outside), 2) maximum temperature threshold of UF 6 , 3) container internal pressure threshold. (J.P.N.)

Computer programs for developing source terms for a UF{sub 6} dispersion model to simulate postulated UF{sub 6} releases from buildings

Energy Technology Data Exchange (ETDEWEB)

Williams, W.R.

1985-03-01

Calculational methods and computer programs for the analysis of source terms for postulated releases of UF{sub 6} are presented. Required thermophysical properties of UF{sub 6}, HF, and H{sub 2}O are described in detail. UF{sub 6} reacts with moisture in the ambient environment to form HF and H{sub 2}O. The coexistence of HF and H{sub 2}O significantly alters their pure component properties, and HF vapor polymerizes. Transient compartment models for simulating UF{sub 6} releases inside gaseous diffusion plant feed and withdrawl buildings and cascade buildings are also described. The basic compartment model mass and energy balances are supported by simple heat transfer, ventilation system, and deposition models. A model that can simulate either a closed compartment or a steady-state ventilation system is also discussed. The transient compartment models provide input to an atmospheric dispersion model as output.

Reasons for Picture Archiving and Communication System (PACS data security breaches: Intentional versus non-intentional breaches

Directory of Open Access Journals (Sweden)

Tintswalo B. Mahlaola

2016-10-01

Objective: The purpose of this article is to explore the nature of and reasons for confidentiality breaches by PACS users in a South African context. Methods: A closed-ended questionnaire was used to collect quantitative data from 115 health professionals employed in a private hospital setting, including its radiology department and a second independent radiology department. The questionnaire sought to explore the attitudes of participants towards confidentiality breeches and reasons for suchbehaviour. Results: Breach incidences were expressed as percentage compliance and classified according to the nature and reasons provided by Sarkar's breach classification. Cross tabulations indicated a statistical significance (p < 0.00 between the expected and observed confidentiality practices of participants and also the adequacy of training, system knowledge and policy awareness. Conclusion: Our study supports previous findings that, in the absence of guidelines, most security breaches were non-intentional acts committed due to ignorance. Of concern are incidents in which sensitive information was intentionally shared via social media.

2D modelling of a UF6 container in a fire

International Nuclear Information System (INIS)

Duret, B.; Seiler, J.M.

1993-01-01

We present some results on 2D thermal modelisation of the behaviour of UF6 in a fire. A cylindrical container is engulfed by a high temperature space where the heat transfer is expected to occur by radiation only. During the first minutes, we assume that the thermal resistance is between the external wall and the UF6 solid, the heat transfer can be split up into three kinds: 1) conduction to solid UF6 through a contact surface. 2) radiative transfer. 3) gas layer with a small heat conductance. This thermal resistance is initially determined by the UF6 filling type, shape and also is time dependant by thermal dilatation effects. On the onset of liquifying the heat transfer increases because of the larger liquid exchange. The liquid and boiling heat flow is then calculated by a model on the basis of classical correlations in vertical cavities. Numerical evaluations have been performed with a finite element model using: ANSYS. With a realistic hypothesis, the effect of the following parameters is estimated: thermal conductivity of UF6 solid, contact surface fraction, UF6 emissivity, gas gap thickness, liquid UF6 wall exchange, solid liquid transition criteria, non condensation factor k. (J.P.N.)

Experimental investigation of fluvial dike breaching due to flow overtopping

Science.gov (United States)

El Kadi Abderrezzak, K.; Rifai, I.; Erpicum, S.; Archambeau, P.; Violeau, D.; Pirotton, M.; Dewals, B.

2017-12-01

The failure of fluvial dikes (levees) often leads to devastating floods that cause loss of life and damages to public infrastructure. Overtopping flows have been recognized as one of the most frequent cause of dike erosion and breaching. Fluvial dike breaching is different from frontal dike (embankments) breaching, because of specific geometry and boundary conditions. The current knowledge on the physical processes underpinning fluvial dike failure due to overtopping remains limited. In addition, there is a lack of a continuous monitoring of the 3D breach formation, limiting the analysis of the key mechanisms governing the breach development and the validation of conceptual or physically-based models. Laboratory tests on breach growth in homogeneous, non-cohesive sandy fluvial dikes due to flow overtopping have been performed. Two experimental setups have been constructed, permitting the investigation of various hydraulic and geometric parameters. Each experimental setup includes a main channel, separated from a floodplain by a dike. A rectangular initial notch is cut in the crest to initiate dike breaching. The breach development is monitored continuously using a specific developed laser profilometry technique. The observations have shown that the breach develops in two stages: first the breach deepens and widens with the breach centerline being gradually shifted toward the downstream side of the main channel. This behavior underlines the influence of the flow momentum component parallel to the dike crest. Second, the dike geometry upstream of the breach stops evolving and the breach widening continues only toward the downstream side of the main channel. The breach evolution has been found strongly affected by the flow conditions (i.e. inflow discharge in the main channel, downstream boundary condition) and floodplain confinement. The findings of this work shed light on key mechanisms of fluvial dike breaching, which differ substantially from those of dam

HEU to LEU Conversion and Blending Facility: UF{sub 6} blending alternative to produce LEU UF{sub 6} for commercial use

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials; the nuclear material will be converted to a form more proliferation- resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. Five technologies for blending HEU will be assessed; blending as UF{sub 6} to produce a UF{sub 6} product for commercial use is one of them. This document provides data to be used in the environmental impact analysis for the UF{sub 6} blending HEU disposition option. Resource needs, employment needs, waste and emissions from plant, hazards, accident scenarios, and intersite transportation are discussed.

Safety provisions for UF{sub 6} handling in the design of a new UF{sub 6} conversion plant

Energy Technology Data Exchange (ETDEWEB)

Bannister, S.P. [British Nuclear Fuels plc, Preston (United Kingdom)

1991-12-31

British Nuclear Fuels plc (BNFL) Fuel Division is currently undertaking the final design and construction of a new UF{sub 6} conversion plant at its production site at Springfields near Preston in the north of England. The Company has gained much experience in the handling of UF{sub 6} during operation of plants on site since 1961. The major hazard occurs during the liquefication cycle and the basis of the maximum credible incident scenario adopted for safety assessment and design purposes is discussed. This paper considers the design features which have been incorporated in the new plant to counter the hazards presented by the presence of UF{sub 6} in gaseous and liquid form and explains current thinking on operational procedures in areas of potential risk such as cylinder filling. The plant emergency response philosophy and systems are described and specific design provisions which have been included to satisfy the UK regulatory bodies are outlined in some detail.

Anisotropy of the fluorine chemical shift tensor in UF6

International Nuclear Information System (INIS)

Rigny, P.

1965-04-01

An 19 F magnetic resonance study of polycrystalline UF 6 is presented. The low temperature complex line can be analyzed as the superposition of two distinct lines, which is attributed to a distortion of the UF 6 octahedron in the solid. The shape of the two components is studied. Their width is much larger than the theoretical dipolar width, and must be explained by large anisotropies of the fluorine chemical shift tensors. The resulting shape functions of the powder spectra are determined. The values of the parameters of the chemical shift tensors yield estimates of the characters of the U-F bonds, and this gives some information on the ground state electronic wave function of the UF 6 molecule in the solid. (author) [fr

SWOT analysis of breach models for common dike failure mechanisms

NARCIS (Netherlands)

Peeters, P.; Van Hoestenberghe, T.; Vincke, L.; Visser, P.J.

2011-01-01

The use of breach models includes two tasks: predicting breach characteristics and estimating flow through the breach. Strengths and weaknesses as well as opportunities and threats of different simplified and detailed physically-based breach models are listed following theoretical and practical

UF6 Cylinder Imaging by Fast Neutron Transmission Tomography

International Nuclear Information System (INIS)

McElroy, R.; Hausladen, P.; Blackston, M.; Croft, S.

2015-01-01

The common use Non-Destructive Assay techniques for the determination of 235 U enrichment and mass of UF6 cylinders used in the production of nuclear reactor fuel require prior knowledge of the physical distribution of the UF6 within the cylinder. The measurement performance for these techniques is typically evaluated based on assumed bounding case distributions of the material. However, little direct data such as radiographic or tomographic images, regarding the distribution of the UF6 within the cylinder is available against which to judge these assumptions. We have developed and tested a prototype active neutron tomographic imaging system employing an Associated Particle Imaging (API) neutron generator and an array of pixelated neutron scintillation counters. This system has been successfully used to obtain the 3-dimensional map of the distribution of UF6 within a type 12B storage cylinder. Results from these measurements are presented and the potential performance and utility of this technique with larger 30B and 48Y cylinders is discussed. (author)

Photochemical removal of NpF6 and PuF6 from UF6 gas streams

International Nuclear Information System (INIS)

Beitz, J.V.; Williams, C.W.

1990-01-01

A novel photochemical method of removing reactive fluorides from UF 6 gas has been discovered. This method reduces generated waste to little more than the volume of the removed impurities, minimizes loss of UF 6 , and can produce a recyclable by-product, fluorine gas. In our new method, impure UF 6 , is exposed to ultraviolet light which dissociates the UF 6 to UF 5 and fluorine atom. Impurities which chemically react with UF 5 are reduced and form solid compounds easily removed from the gas while UF 5 is converted back to UF 6 . Proof-of-concept testing involved UF 6 containing NpF 6 and PuF 6 with CO added as a fluorine atom scavenger. In a single photolysis step, greater than 5000-fold reduction of PuF 6 was demonstrated while reducing NpF 6 by more than 40-fold. This process is likely to remove corrosion and fission product fluorides that are more reactive than UF 6 and has been demonstrated without an added fluorine atom scavenger by periodically removing photogenerated fluorine gas. 44 refs., 3 figs., 2 tabs

Perekayasaan Heat Exchanger Sebagai Pemanas Umpan Uf 6 Dalam Pabrik Elemen Bakar Nuklir

OpenAIRE

Zacharias, Petrus; Pancoko, Marliyadi

2011-01-01

DESIGN OF HEAT EXCHANGER FOR HEATING UF6 FEED IN NUCLEAR FUEL ELEMENT PLANT. The process of conversion of UF6 to UO through Integrated Dry Route (IDR) i s done in a rotary kiln reactor. There are two stages of initi al treatment / conditioni ng before inserting the UF 6 in to the reactor : changing UF6 2 solid into the gas phase at a temperature of 60°C in an evaporator, and then, raising the temperature of UF C to 2900 C i n a Heat Exchanger (HE). Therefore it i s necessary to desi gn...

Investigation of technology for the monitoring of UF6 mass flow in UF6 streams diluted with H2

International Nuclear Information System (INIS)

Baker, O.J.; Cooley, J.N.; Hewgley, W.A.; Moran, B.W.; Swindle, D.W. Jr.

1986-12-01

The applicability, availability, and effectiveness of gas flow meters are assessed as a means for verifying the mass flows of pure UF 6 streams diluted with a carrier gas. The initial survey identified the orifice, pitot tube, thermal, vortex shedding, and vortex precession (swirl) meters as promising for the intended use. Subsequent assessments of these flow meters revealed that two - the orifice meter and the pitot tube meter - are the best choices for the proposed applications: the first is recommended for low velocity gas, small diameter piping; the latter, for high velocity gas, large diameter piping. Final selection of the gas flow meters should be based on test loop evaluations in which the proposed meters are subjected to gas flows, temperatures, and pressures representative of those expected in service. Known instruments are evaluated that may be applicable to the measurement of uranium or UF 6 concentration in a UF 6 - H 2 process stream at an aerodynamic enrichment plant. Of the six procedures evaluated, four have been used for process monitoring in a UF 6 environment: gas mass spectrometry, infrared-ultraviolet-visible spectrophotometry, gas chromatography, and acoustic gas analysis. The remaining two procedures, laser fluorimetry and atomic absorption spectroscopy, would require significant development work before they could be used for process monitoring. Infrared-ultravioloet-visible spectrophotometry is judged to be the best procedure currently available to perform the required measurement

Federal Information Security and Data Breach Notification Laws

Science.gov (United States)

2009-01-29

The following report describes information security and data breach notification requirements included in the Privacy Act, the Federal Information...information for unauthorized purposes. Data breach notification laws typically require covered entities to implement a breach notification policy, and...Feinstein), S. 495 (Leahy), and S. 1178 (Inouye)--were reported favorably out of Senate committees. Those bills include information security and data

Investigation of technology for monitoring UF6 mass flow

International Nuclear Information System (INIS)

Cooley, J.N.; Moran, B.W.; Swindle, D.W. Jr.

1987-06-01

The applicability of gas flow meters, in-line enrichment monitors, and instruments for measuring uranium or UF 6 concentrations in process streams as a means for verifying declared plant throughput have been investigated. The study was performed to assist the International Atomic Energy Agency in the development of an effective international safeguards approach for aerodynamic uranium enrichment plants. Because the process gas in an aerodynamic enrichment facility is a mixture of UF 6 and H 2 , a mass flow measurement in conjunction with a measurement of the uranium (or UF 6 ) concentration in the process gas is required to quantify the amount of uranium being fed into, and withdrawn from, the cascades for nuclear materials accountability verification. In-line enrichment monitors developed for the US gas centrifuge enrichment plant are found to be applicable only to pure UF 6 streams. Of the five gas flow meters evaluated, the orifice meter and the pitot tube meter are judged the best choices for the proposed applications: the first is recommended for low-velocity gas, small diameter piping; the latter, for high-velocity gas, large diameter piping. Of the six procedures evaluated for measurement of uranium or UF 6 concentration in a mixed process stream, infrared-ultraviolet-visible spectrophotometry is judged to be the best procedure currently available to perform the required measurement. 4 refs., 3 figs., 3 tabs

Investigation of the UF6 aerosol behavior in air, (4)

International Nuclear Information System (INIS)

Ishida, Junichiro; Sakamoto, Genji; Takeda, Seiichi; Kato, Jinzo

1979-01-01

When gaseous uranium hexafluoride (UF 6 ) is released into air, it hydrolizes with moisture in air to produce HF gas and particulate UO 2 F 2 which is visible. The lowest visible concentration in air is about 5 x 10 -8 μCi/cm 3 in case of releasing UF 6 and about 10 -9 μCi/cm 3 in case of released UF 6 cloud. By watching the occurrence of released UF 6 cloud, it is possible to take necessary action without delay. But in the case that there is no one to watch or that the concentration is not high enough to be visible, an alarm monitor system has to be relied on. Therefore the characteristics of the alarm monitors which can detect UF 6 promptly were examined. As UF 6 is hydrolized into gaseous HF and particulate UO 2 F 2 , three monitoring methods are considered; (1) to detect the alpha radiation of uranium, (2) to detect HF gas and (3) to detect airborne particles (aerosol). Performance tests were conducted on an alpha dust monitor, an electrochemical HF monitor, a thin film electrolyte HF monitor and an ionized smoke detector. The relationship between radioactivity concentration and HF concentration was investigated especially regarding with the conditions of released UF 6 amount and the distance from a release point to the observation point. The experimental facilities containing a large glove-box made of SUS and acrylic resin walls, a dust monitor, an HF monitor, a smoke detector and a filter, and the experimental procedure are explained. As the experimental results, the response characteristics of the dust monitor and HF monitor, the relationship of radioactivity concentration to HF concentration in air and the relation of the distance from the release point to the concentration of U and HF are presented. (Nakai, Y.)

Final programmatic environmental impact statement for alternative strategies for the long-term management and use of depleted uranium hexafluoride. Volume 3: Responses to public comments

International Nuclear Information System (INIS)

1999-04-01

This PEIS assesses the potential impacts of alternative management strategies for depleted uranium hexafluoride (UF 6 ) currently stored at three DOE sites: Paducah site near Paducah, Kentucky, Portsmouth site near Portsmouth, Ohio; and K-25 site on the Oak Ridge Reservation, Oak Ridge, Tennessee. The alternatives analyzed in the PEIS include no action, long-term storage as UF 6 , long-term storage as uranium oxide, use as uranium oxide, use as uranium metal, and disposal. DOE's preferred alternative is to begin conversion of the depleted UF 6 inventory as soon as possible, either to uranium oxide, uranium metal, or a combination of both, while allowing for use of as much of this inventory as possible. This volume of the Final PEIS contains the comments and DOE's responses to comments received during the comment period. Chapter 2 contains photocopies of written submissions received by DOE on the Draft PEIS; DOE's responses to those comments are listed in Chapter 3. Chapter 4 provides the oral comments received at the public hearings and DOE's responses. Chapter 5 provides indices to comments and responses arranged by commentor name and by comment number

Teaching Case: Security Breach at Target

Science.gov (United States)

Plachkinova, Miloslava; Maurer, Chris

2018-01-01

This case study follows the security breach that affected Target at the end of 2013 and resulted in the loss of financial data for over 70 million customers. The case provides an overview of the company and describes the reasons that led to one of the biggest security breaches in history. It offers a discussion on Target's vendor management…

Data security breaches and privacy in Europe

CERN Document Server

Wong, Rebecca

2013-01-01

Data Security Breaches and Privacy in Europe aims to consider data protection and cybersecurity issues; more specifically, it aims to provide a fruitful discussion on data security breaches. A detailed analysis of the European Data Protection framework will be examined. In particular, the Data Protection Directive 95/45/EC, the Directive on Privacy and Electronic Communications and the proposed changes under the Data Protection Regulation (data breach notifications) and its implications are considered. This is followed by an examination of the Directive on Attacks against information systems a

New regulatory aspects of UF6 transport

International Nuclear Information System (INIS)

Biaggio, A.L.; Lee Gonzales, H.M.; Lopez Vietri, J.R.; Novo, R.G.

1987-01-01

In nuclear industry, a great amount of uranium is transformed from a chemical form to another. When the fuel cycle requires enrichment, uranium hexafluoride (UF 6) is handled, stored and transported in great quantities. To analyze the risks involved in possible accidents associated with UF 6 , radiological and chemical aspects must be considered. So far, the international practice was based on the adoption of regulations from a particular country (ANSI No. 14.1-1982.U.S.A.). In this way, the adoption of these norms at international level is difficult. For that reason, the International Atomic Energy Agency has attempted to consider the chemical risks associated with UF 6 in order to establish a more universal basis ('Recommendations for Providing Protection during the Transport of Uranium Hexafluoride' IAEA-TECDOC-423, Vienna, June 1987 - Austria). A critical analysis of these recommendations is presented in this work. The coherence and the degree of completion of the new recommendations are evaluated and the safety level is compared with that of the accepted regulations for toxic or corrosive substances and for radioactive materials transport. (Author)

Simulation of Breach Outflow for Earthfill Dam

International Nuclear Information System (INIS)

Razad, Azwin Zailti Abdul; Muda, Rahsidi Sabri; Sidek, Lariyah Mohd; Azia, Intan Shafilah Abdul; Mansor, Faezah Hanum; Yalit, Ruzaimei

2013-01-01

Dams have been built for many reasons such as irrigation, hydropower, flood mitigation, and water supply to support development for the benefit of human. However, the huge amount of water stored behind the dam can seriously pose adverse impacts to the downstream community should it be released due to unwanted dam break event. To minimise the potential loss of lives and property damages, a workable Emergency Response Plan is required to be developed. As part of a responsible dam owner and operator, TNB initiated a study on dam breach modelling for Cameron Highlands Hydroelectric Scheme to simulate the potential dam breach for Jor Dam. Prediction of dam breach parameters using the empirical equations of Froehlich and Macdonal-Langridge-Monopolis formed the basis of the modelling, coupled with MIKE 11 software to obtain the breach outflow due to Probable Maximum Flood (PMF). This paper will therefore discuss the model setup, simulation procedure and comparison of the prediction with existing equations.

Dam Break Analysis of Embankment Dams Considering Breach Characteristics

Directory of Open Access Journals (Sweden)

Abolfazl Shamsaei

2004-05-01

Full Text Available The study of dam's break, needs the definition of various parameters such as the break cause, its type, its dimension and the duration of breach development. The precise forecast for different aspects of the breach is one of the most important factors for analyzing it in embankment dam. The characteristics of the breach and determination of their vulnerability has the most effect on the waves resulting from dam break. Investigating, about the parameters of the breach in "Silveh" earth dam have been determined using the suitable model. In Silve dam a trapezoid breach with side slope z=0.01m and the average base line b=80m was computed. The duration of the breaches development is 1.9 hour. Regarding the above results and the application of DAM Break software the consequences of the probable break of the dam was determined. The analysis of the results of water covering of the city of Piranshahr located 12km from silve dam confirms that in 3 hours the water will reach the height (level of 1425 meters.

Aspects of uranium chemistry pertaining to UF{sub 6} cylinder handling

Energy Technology Data Exchange (ETDEWEB)

Ritter, R.L.; Barber, E.J. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31

Under normal conditions, the bulk of UF{sub 6} in storage cylinders will be in the solid state with an overpressure of gaseous UF{sub 6} well below one atmosphere. Corrosion of the interior of the cylinder will be very slow, with formation of a small amount of reduced fluoride, probably U{sub 2}F{sub 9}. The UO{sub 3}-HF-H{sub 2}O phase diagram indicates that reaction of any inleaking water vapor with the solid UF{sub 6} will generate the solid material [H{sub 3}O]{sub 2}(U(OH){sub 4}F{sub 4}) in equilibrium with an aqueous HF solution containing only small amounts of uranium. The corrosion of the steel cylinder by these materials may be enhanced over that observed with gaseous anhydrous UF{sub 6}.

In-reactor cladding breach of EBR-II driver-fuel elements

International Nuclear Information System (INIS)

Seidel, B.R.; Einziger, R.E.

1977-01-01

Knowledge of performance and minimum useful element lifetime of Mark-II driver-fuel elements is required to maintain a high plant operating capacity factor with maximum fuel utilization. To obtain such knowledge, intentional cladding breach has been obtained in four run-to-cladding-breach Mark-II experimental driver-fuel subassemblies operating under normal conditions in EBR-II. Breach and subsequent fission-product release proved benign to reactor operations. The breaches originated on the outer surface of the cladding in the root of the restrainer dimples and were intergranular. The Weibull distribution of lifetime accurately predicts the observed minimum useful element lifetime of 10 at.% burnup, with breach ensuing shortly thereafter

The characterization and monitoring of metallic fuel breaches in EBR-2

International Nuclear Information System (INIS)

Pahl, R.G.; Batte, G.L.; Mikaili, R.; Lambert, J.D.B.; Hofman, G.L.

1991-01-01

This paper discusses the characterization and monitoring of metallic fuel breaches which is now a significant part of the Integral Fast Reactor fuel testing program at Argonne National Laboratory. Irradiation experience with failed metallic fuel now includes natural breaches in the plenum and fuel column regions in lead ''endurance'' tests as well as fuel column breaches in artificially-defected fuel which have operated for months in the run-beyond-cladding breach (RBCB) mode. Analyses of the fission gas (FG) release-to-birth (R/B) ratios of selected historical breaches have been completed and have proven to be very useful in differentiating between plenum and fuel column breaches

The ultimate disposition of depleted uranium

Energy Technology Data Exchange (ETDEWEB)

1990-12-01

Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

Preliminary Hazard Analysis applied to Uranium Hexafluoride - UF6 production plant

International Nuclear Information System (INIS)

Tomzhinsky, David; Bichmacher, Ricardo; Braganca Junior, Alvaro; Peixoto, Orpet Jose

1996-01-01

The purpose of this paper is to present the results of the Preliminary hazard Analysis applied to the UF 6 Production Process, which is part of the UF 6 Conversion Plant. The Conversion Plant has designed to produce a high purified UF 6 in accordance with the nuclear grade standards. This Preliminary Hazard Analysis is the first step in the Risk Management Studies, which are under current development. The analysis evaluated the impact originated from the production process in the plant operators, members of public, equipment, systems and installations as well as the environment. (author)

The electron spectrum of UF6 recorded in the gas phase

Science.gov (United States)

Mârtensson, N.; Malmquist, P.-Å.; Svensson, S.; Johansson, B.

1984-06-01

Gas phase core and valence electron spectra from UF6, excited by AlKα monochromatized x rays, in the binding energy range 0-1000 eV are presented. It is shown that the AlKα excited valence electron spectrum can be used to reassign the highest occupied molecular orbital (HOMO) in UF6. Many-body effects on the core levels are discussed and core level lifetimes are determined. The shift between solid phase and gas phase electron binding energies for core lines is used to discuss the U5 f population in UF6.

UF{sub 6} cylinder inspections at PGDP

Energy Technology Data Exchange (ETDEWEB)

Lamb, G.W.; Whinnery, W.N. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Routine inspections of all UF{sub 6} cylinders at the Paducah Gaseous Diffusion Plant have been mandated by the Department of Energy. A specific UF{sub 6} cylinder inspection procedure for what items to inspect and training for the operators prior to inspection duty are described. The layout of the cylinder yards and the forms used in the inspections are shown. The large number of cylinders (>30,000) to inspect and the schedule for completion on the mandated time table are discussed. Results of the inspections and the actions to correct the deficiencies are explained. Future inspections and movement of cylinders for relocation of certain cylinder yards are defined.

25 CFR 163.42 - Obligated service and breach of contract.

Science.gov (United States)

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Obligated service and breach of contract. 163.42 Section... breach of contract. (a) Obligated service. (1) Individuals completing forestry education programs with an... request for waiver. (b) Breach of contract. Any individual who has participated in and accepted financial...

Gas-phase UF6 enrichment monitor for enrichment plant safeguards

International Nuclear Information System (INIS)

Strittmatter, R.B.; Tape, J.W.

1980-03-01

An in-line enrichment monitor is being developed to provide real-time enrichment data for the gas-phase UF 6 feed stream of an enrichment plant. The nondestructive gamma-ray assay method can be used to determine the enrichment of natural UF 6 with a relative precision of better than 1% for a wide range of pressures

High temperature experiments on a 4 tons UF6 container TENERIFE program

Energy Technology Data Exchange (ETDEWEB)

Casselman, C.; Duret, B.; Seiler, J.M.; Ringot, C.; Warniez, P.

1991-12-31

The paper presents an experimental program (called TENERIFE) whose aim is to investigate the behaviour of a cylinder containing UF{sub 6} when exposed to a high temperature fire for model validation. Taking into account the experiments performed in the past, the modelization needs further information in order to be able to predict the behaviour of a real size cylinder when engulfed in a 800{degrees}C fire, as specified in the regulation. The main unknowns are related to (1) the UF{sub 6} behaviour beyond the critical point, (2) the relationship between temperature field and internal pressure and (3) the equivalent conductivity of the solid UF{sub 6}. In order to investigate these phenomena in a representative way it is foreseen to perform experiments with a cylinder of real diameter, but reduced length, containing 4 tons of UF{sub 6}. This cylinder will be placed in an electrically heated furnace. A confinement vessel prevents any dispersion of UF{sub 6}. The heat flux delivered by the furnace will be calibrated by specific tests. The cylinder will be changed for each test.

Natural phenomena evaluations of the K-25 site UF6 cylinder storage yards

International Nuclear Information System (INIS)

Fricke, K.E.

1996-01-01

The K-25 Site UF 6 cylinder storage yards are used for the temporary storage of UF 6 normal assay cylinders and long-term storage of other UF 6 cylinders. The K-25 Site UF 6 cylinder storage yards consist of six on-site areas: K-1066-B, K-1066-E, K-1066-F, K-1066-J, K-1066-K and K-1066-L. There are no permanent structures erected on the cylinder yards, except for five portable buildings. The operating contractor for the K-25 Site is preparing a Safety Analysis Report (SAR) to examine the safety related aspects of the K-25 Site UF 6 cylinder storage yards. The SAR preparation encompasses many tasks terminating in consequence analysis for the release of gaseous and liquid UF 6 , one of which is the evaluation of natural phenomena threats, such as earthquakes, floods, and winds. In support of the SAR, the six active cylinder storage yards were evaluated for vulnerabilities to natural phenomena, earthquakes, high winds and tornados, tornado-generated missiles, floods (local and regional), and lightning. This report summarizes those studies. 30 refs

Probabilistic assessment of spent-fuel cladding breach

International Nuclear Information System (INIS)

Foadian, H.; Rashid, Y.R.; Seager, K.D.

1991-01-01

A methodology for determining the probability spent-fuel cladding breach due to normal and accident class B cask transport conditions is introduced. This technique uses deterministic stress analysis results as well as probabilistic cladding material properties, initial flaws, and breach criteria. Best estimates are presented for the probability distributions of irradiated Zircaloy properties such as ductility and fracture toughness, and for fuel rod initial conditions such as manufacturing flaws and PCI part-wall cracks. Example analyses are used to illustrate the implementation of this methodology for a BWR (GE 7 x 7) and a PWR (B ampersand W 15 x 15) assembly. The cladding breach probabilities for each assembly are tabulated for regulatory normal and accident transport conditions including fire

Probabilistic assessment of spent-fuel cladding breach

International Nuclear Information System (INIS)

Foadian, H.; Rashid, Y.R.; Seager, K.D.

1992-01-01

In this paper a methodology for determining the probability of spent-fuel cladding breach due to normal and accident class B cask transport conditions is introduced. This technique uses deterministic stress analysis results as well as probabilistic cladding material properties, initial flaws, and breach criteria. Best estimates are presented for the probability distributions of irradiated Zircaloy properties such as ductility and fracture toughness, and for fuel rod initial conditions such as manufacturing flaws and PCI part-wall cracks. Example analyses are used to illustrate the implementation of this methodology for a BWR (GE 7 x 7) and a PWR (B and W 15 x 15) assembly. The cladding breach probabilities for each assembly are tabulated for regulatory normal and accident transport conditions including fire

Epidemiologisk forskning om uførepensjon i Norden

Directory of Open Access Journals (Sweden)

Johan Håkon Bjørngaard

2010-01-01

Full Text Available En relativ stor andel av befolkningen i yrkesaktiv alder i de nordiske landene mottar uførepensjon, og i Norge er det en klar tendens til økning. Parallelt med dette har interessen for forskning rundt uførepensjon som fenomen økt. Vi har i denne studien beskrevet den epidemiologiske forskningen om uførepensjon i Norden. I en systematisk litteraturgjennomgang fant vi 118 aktuelle artikler. Alle de nordiske landene er godt representert. Kohortstudier med uførepensjon som endepunkt utgjorde hovedvekten av materialet, hvor 67 var populasjonsbaserte mens 29 tok utgangspunkt i selekterte pasientpopulasjoner. I alt seks kohortstudier benyttet uførepensjon som eksponering. Vi fant videre syv kasus-kontrollstudier og ni forsøk. Det er betydelig dokumentasjon på at ulike sykdommer og helseplager er assosiert med økt risiko for uførhet, i tillegg til at sosioøkonomiske og arbeidsrelaterte forhold er av betydning. Gjennomgangen viser at den epidemiologiske forskningen for det meste har rettet blikket mot individuelle årsaker til uførepensjonering. Selv om denne forskningen er viktig, kan den neppe forklare økningen vi har sett i det siste tiåret. Den videre forskningen bør utforske nærmere hvordan individuell sårbarhet ender i utstøtelse fra arbeidslivet. Med tanke på den omfattende forskningen om årsaker på dette feltet, bør man også i større grad gjennomføre forsøk for å bedre utsatte gruppers arbeidsdeltakelse.Bjørngaard JH, Krokstad S, Johnsen R, Karlsen AO, Pape K, Støver M, Sund E, Westin S. Epidemiological research on disability benefits in the Nordic countries. Nor J Epidemiol 2009; 19 (2: 103-114 ENGLISH SUMMARYA substantial part of the workforce in the Nordic countries receives a disability benefit, and in Norway this beneficiary rate is growing. As a result, disability benefit has been the subject of new interest and research. In this study we have reviewed the epidemiological research on disability benefit in the

Properties of Sago Particleboards Resinated with UF and PF Resin

Directory of Open Access Journals (Sweden)

Chen Chiang Tay

2016-01-01

Full Text Available The sago processing industry in Mukah, Sarawak, had generated huge amount of sago waste after the milling process and scientists have employed the waste into composite material. In this work, sago residues were mixed with the Phenol Formaldehyde (PF and Urea Formaldehyde (UF for particleboard fabrication. The fabrication and testing methods are based on JIS A 5908 Standard. A single layer particleboard using sago particles was fabricated at targeted density of 600 kg/m3. Particles with weight fractions of 90%, 85%, and 80% with two different matrices were used in the fabrication. The results demonstrated that the samples with different weight fraction and matrix have great influence on the mechanical properties such as MOR, MOE, Young’s Modulus, tensile strength, impact strength, screw test, and internal bonding. The sago UF/PF particleboard only displays single stage decomposition. All the panels underwent physical tests which are water absorption and thickness swelling. The combination of sago particles with UF/PF can be utilized for general indoor application purposes such as furniture manufacturing. Sago particleboard made by UF/PF provided the advantages like optimized performance, minimized weight and volume, cost effectiveness, chemical resistance, and resistance to biodegradation.

On-Line Enrichment Monitor for UF{sub 6} Gas Centrifuge Enrichment Plant

Energy Technology Data Exchange (ETDEWEB)

Ianakiev, K. D.; Boyer, B.; Favalli, A.; Goda, J. M.; Hill, T.; Keller, C.; Lombardi, M.; Paffett, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.; Parker, R.; Smith, M. K.; Swinhoe, M. T. [Los Alamos National Laboratory, Los Alamos (United States)

2012-06-15

This paper is a continuation of the Advanced Enrichment Monitoring Technology for UF{sub 6} Gas Centrifuge Enrichment Plant (GCEP) work, presented in the 2010 IAEA Safeguards Symposium. Here we will present the system architecture for a planned side-by-side field trial test of passive (186-keV line spectroscopy and pressure-based correction for UF{sub 6} gas density) and active (186-keV line spectroscopy and transmission measurement based correction for UF{sub 6} gas density) enrichment monitoring systems in URENCO's enrichment plant in Capenhurst. Because the pressure and transmission measurements of UF{sub 6} are complementary, additional information on the importance of the presence of light gases and the UF{sub 6} gas temperature can be obtained by cross-correlation between simultaneous measurements of transmission, pressure and 186-keV intensity. We will discuss the calibration issues and performance in the context of accurate, on-line enrichment measurement. It is hoped that a simple and accurate on-line enrichment monitor can be built using the UF{sub 6} gas pressure provided by the Operator, based on online mass spectrometer calibration, assuming a negligible (a small fraction of percent) contribution of wall deposits. Unaccounted-for wall deposits present at the initial calibration will lead to unwanted sensitivity to changes in theUF{sub 6} gas pressure and thus to error in the enrichment results. Because the accumulated deposits in the cascade header pipe have been identified as an issue for Go/No Go measurements with the Cascade Header Enrichment Monitor (CHEM) and Continuous Enrichment Monitor (CEMO), it is important to explore their effect. Therefore we present the expected uncertainty on enrichment measurements obtained by propagating the errors introduced by deposits, gas density, etc. and will discuss the options for a deposit correction during initial calibration of an On-Line Enrichment Monitor (OLEM).

Breach to Nowhere

Science.gov (United States)

Schaffhauser, Dian

2009-01-01

Will that data breach be the end of a chief security officer (CSO)? Managing information security in higher education requires more than just technical expertise, especially when the heat is cranked up. This article takes a look at how two CSOs deal with hack attacks at their universities. When Purdue University Chief Information Security Officer…

Évolution qualitative et quantitative des composantes de l'œuf ...

African Journals Online (AJOL)

SARAH

28 févr. 2014 ... contrôle de coquille et de calibre dans les fermes. Mots clés : œuf, pondeuse, ... dynamique qualitative des composantes de l'œuf . Certains auteurs ont ... programme de conduite et de gestion d'élevage. Élevées en bande ...

Kinetics of magnesiothermic reduction of UF4 by DTA

International Nuclear Information System (INIS)

Raina, Amulya; Agarwal, Renu

2016-01-01

Uranium metal production for nuclear fuel is usually carried out by magnesio-thermic reduction of UF 4 (s). This is a highly exothermic reaction: UF 4 +2Mg → 2MgF 2 + U, ΔH r 298.15 K = -349 kJ/mol. The process is carried out by loading 1:2 molar ratio of UF 4 and Mg mixture in a large stainless steel vessel lined with insulating MgF 2 . This bomb reactor is heated to ~1023 K, but the reaction is known to start at lower temperature. The furnace heat and reaction heat results in shooting mixture temperature to >1800 K. Attaining such high temperatures is desired for complete segregation of fluoride slag (T m MgF 2 =1538 K) and uranium melt (T m =1406 K) due to large difference in their densities, 3.4 gm/cc and 17.9 gm/cc, respectively. For efficient and economic magnesio-thermic reduction of UF 4 , it is desired to understand heat distribution in the reactor vessel, which requires kinetic parameters of this reaction: activation energy (E α ) and A. As this is a solid-solid reaction, studying this reaction kinetics can be approximated by nonisothermal DTA analysis using different heating rates. For non-isothermal conditions, the heating rate (ϕ) = dT/dt is related to rate of propagation of reaction

Transport of UF6 in compliance with TS-R-1

International Nuclear Information System (INIS)

Dekker, B.G.

2004-01-01

The IAEA Regulations TS-R-1 (ST-1, Revised) 1996 Edition include requirements for packages containing uranium hexafluoride (UF6); these are the first and only substance-specific requirements in the IAEA regulations. These requirements have already particularly affected, and will further affect, the transport of non-fissile and fissile excepted UF 6 and the packages used for these transports. Non-fissile and fissile excepted UF6 (ASTM C 787) has been transported worldwide for decades in a safe and reliable manner, using internationally standardised packages. Under the auspices of the World Nuclear Transport Institute (WNTI), an industry working group has been evaluating the existing packages against the requirements in TS-R-1. As new requirements came into effect, there were new challenges for the use of these standard packages, including the free drop test and the thermal requirements. In close cooperation with the WNTI HEXT Industry Working Group, a consortium of UF6 producers/users has worked together on the design and development, testing and certification of technical solutions for modification and optimisation of the existing packages to comply with TS-R-1. This paper reviews the existing standard packages against the requirements in TS-R-1. An update is also given describing the enhancements to the standard packages that have been designed and developed recently. The paper also describes how these solutions have been tested and certified, as well as the status of implementation. Finally, a review is made of the options that are available internationally to transport UF6 in compliance with TS-R-1. (author)

Confirmatory measurements of UF6 using the neutron self-interrogation method

International Nuclear Information System (INIS)

Stewart, J.E.; Ensslin, N.; Menlove, H.O.; Cowder, L.R.; Polk, P.J.

1985-01-01

A passive neutron counting method has been developed for measurement of the 235 U mass in Model 5A cylinders of UF 6 . The unique neutronic properties of UF 6 containing highly enriched uranium (HEU) permit 235 U assay using only passive neutron counting. The sample effectively assays itself by self-interrogation. Shipped from enrichment plants and received at fuel fabrication and conversion facilities, 5A UF 6 cylinders hold up to approx.17 kg of 235 U each. Field measurements at the Portsmouth Gaseous Diffusion Plant (GDP) showed an average assay accuracy of 6.8% (1sigma) for 44 cylinders with enrichments from 6 to 98% and with a range of fill heights. Further measurements on 38 cylinders containing 97%-enriched material yielded an accuracy of 2.8% (1sigma). Typical counting times for these measurements were less than 5 min. An in-plant instrument for receipts confirmation measurements of 5A UF 6 cylinders has been developed for the Savannah River Plant. The Receipts Assay Monitor (RAM) is currently being tested and calibrated. It is designed to confirm declared fissile mass in all incoming 5A cylinders containing HEU in the form of UF 6 . One of the computer-controlled features is a removable cadmium liner for the sample cavity. The liner allows a sample fill-height correction, which significantly improves assay accuracy

A SWOT analysis of hydrodynamic models with respect to simulating breaching

NARCIS (Netherlands)

van Damme, M.; Visser, P.J.

2015-01-01

Deriving the bed shear stresses from hydrodynamic models in breach models is challenging due to the continuous changing hydraulic head over the breach in combination with horizontal and vertical flow contractions, and the continuous rapidly changing breach geometry. Three stages can be distinguished

Conscientiousness and reactions to psychological contract breach: a longitudinal field study.

Science.gov (United States)

Orvis, Karin A; Dudley, Nicole M; Cortina, Jose M

2008-09-01

The authors examined the role of employee conscientiousness as a moderator of the relationships between psychological contract breach and employee behavioral and attitudinal reactions to the breach. They collected data from 106 newly hired employees within the 1st month of employment (Time 1), 3 months later (Time 2), and 8 months after Time 1 (Time 3) to observe the progression through contract development, breach, and reaction. Results suggest that conscientiousness is a significant moderator for 4 of the 5 contract breach-employee reaction relationships examined (turnover intentions, organizational loyalty, job satisfaction, and 1 of 2 facets of job performance). Specifically, employees who were lower in conscientiousness had more negative reactions to perceived breach with respect to turnover intentions, organizational loyalty, and job satisfaction. In contrast, employees who were higher in conscientiousness reduced their job performance to a greater degree in response to contract breach. Future research directions are discussed.

Tapping Transaction Costs to Forecast Acquisition Cost Breaches

Science.gov (United States)

2016-01-01

experience a cost breach. In our medical example, we could use survival analysis to identify risk fac- tors, such as obesity , that might indicate a greater... exogenous variables on the probability of a dichotomous outcome, such as whether or not a cost breach occurs in any given program year. Logit is

Incomplete Information, Renegotiation, and Breach of Contract

OpenAIRE

Jihong Lee

2005-01-01

Once a contract has been agreed by two agents, the problem of renegotiating breach under two-sided asymmetric information on the agents' outside options is equivalent to the problem of bilateral trade with uncertain gains. Thus, the theorem of Myerson and Satterthwaite (1983) implies the impossibility of efficient renegotiation. We also show that, assuming no renegotiation, the optimal breach mechanism in this setting corresponds to the expectation damage rule.

18 years experience on UF{sub 6} handling at Japanese nuclear fuel manufacturer

Energy Technology Data Exchange (ETDEWEB)

Fujinaga, H.; Yamazaki, N.; Takebe, N. [Japan Nucelar Fuel Conversion Co., Ltd., Ibaraki (Japan)

1991-12-31

In the spring of 1991, a leading nuclear fuel manufacturing company in Japan, celebrated its 18th anniversary. Since 1973, the company has produced over 5000 metric ton of ceramic grade UO{sub 2} powder to supply to Japanese fabricators, without major accident/incident and especially with a successful safety record on UF{sub 6} handling. The company`s 18 years experience on nuclear fuel manufacturing reveals that key factors for the safe handling of UF{sub 6} are (1) installing adequate facilities, equipped with safety devices, (2) providing UF{sub 6} handling manuals and executing them strictly, and (3) repeating on and off the job training for operators. In this paper, equipment and the operation mode for UF{sub 6} processing at their facility are discussed.

Electron affinity of UF6. Final report, March 1, 1976--June 30, 1977

International Nuclear Information System (INIS)

Rothe, E.W.

1977-06-01

Ionization reactions are observed in crossed molecular beams, usually of thermal energy, alkalis and MoF 6 , WF 6 and UF 6 . Previous studies have indicated large electron affinities for these hexafluorides, and this is confirmed here. Ionization at thermal energies proceeds with the alkali dimers, A 2 , for all three hexafluorides, but with alkali atoms, A, only for UF 6 . Several ionization paths are observed, allowing the deduction of molecular energies. A few experiments are done with eV-range beams. Lower limits for the elecron affinities are 4.5, 3.3, 4.9, 4.3 and 1.9 eV for MoF 6 , MoF 5 , WF 6 , UF 6 and UF 5 , respectively. Possible mechanisms are discussed

Results of ultrasonic testing evaluations on UF6 storage cylinders

International Nuclear Information System (INIS)

Lykins, M.L.

1997-02-01

The three site cylinder management program is responsible for the safe storage of the DOE owned UF 6 storage cylinders at PORTS, PGDP and at the K-25 site. To ensure the safe storage of the UF 6 in the cylinders, the structural integrity of the cylinders must be evaluated. This report represents the latest cylinder integrity investigation that utilized wall thickness evaluations to identify thinning due to atmospheric exposure

UF{sub 6} tiedowns for truck transport - right way/wrong way

Energy Technology Data Exchange (ETDEWEB)

Stout, F.W. Jr. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31

Tiedown systems for truck transport of UF{sub 6} must be defined and controlled to assure the least risk for hauling the material over the highways. This paper and an associated poster display will present the current status of regulatory criteria for tiedowns, analyze the structural stresses involved in tiedowns for two major UF{sub 6} packaging systems, the 21PF series of overpacks and the 48 in. diameter shipping cylinders, and will present photographs showing some {open_quote}right ways{close_quotes} and some {open_quotes}wrong (or risky) ways{close_quotes} currently used for tiedown systems. Risky tiedown methods must be replaced with safer less risky methods to insure the safe transport of UF{sub 6}.

Influence of Personality on Perception of Psychological Contract Breach

Directory of Open Access Journals (Sweden)

Hassan Jafri

2014-10-01

Full Text Available The present research aimed to investigate the influence of personality (Five-Factor Model on Psychological Contract Breach. Using random sampling procedure, data were collected from 90 faculties of colleges of Royal University of Bhutan. Personality scales by John, Naumann, and Soto (2008 and Robinson and Morrison’s (2000 Psychological Contract Breach scale were used in this study. Correlation and regression analysis were carried out to analyze the obtained data. Results revealed that Extraversion and Neuroticism dimensions of the personality model have been found to be positively associated with the perception of breach. Employees who are by nature Agreeable and Conscientiousness are less likely to perceive breach in their psychological contract. Organization should look into the personality aspect while recruiting employees. If employees are hired with certain personality traits, they may focus on their performance and organizational growth.

Inversion Method for Early Detection of ARES-1 Case Breach Failure

Science.gov (United States)

Mackey, Ryan M.; Kulikov, Igor K.; Bajwa, Anupa; Berg, Peter; Smelyanskiy, Vadim

2010-01-01

A document describes research into the problem of detecting a case breach formation at an early stage of a rocket flight. An inversion algorithm for case breach allocation is proposed and analyzed. It is shown how the case breach can be allocated at an early stage of its development by using the rocket sensor data and the output data from the control block of the rocket navigation system. The results are simulated with MATLAB/Simulink software. The efficiency of an inversion algorithm for a case breach location is discussed. The research was devoted to the analysis of the ARES-l flight during the first 120 seconds after the launch and early prediction of case breach failure. During this time, the rocket is propelled by its first-stage Solid Rocket Booster (SRB). If a breach appears in SRB case, the gases escaping through it will produce the (side) thrust directed perpendicular to the rocket axis. The side thrust creates torque influencing the rocket attitude. The ARES-l control system will compensate for the side thrust until it reaches some critical value, after which the flight will be uncontrollable. The objective of this work was to obtain the start time of case breach development and its location using the rocket inertial navigation sensors and GNC data. The algorithm was effective for the detection and location of a breach in an SRB field joint at an early stage of its development.

Do Data Breach Disclosure Laws Reduce Identity Theft?

Science.gov (United States)

Romanosky, Sasha; Telang, Rahul; Acquisti, Alessandro

2011-01-01

In the United States, identity theft resulted in corporate and consumer losses of $56 billion dollars in 2005, with up to 35 percent of known identity thefts caused by corporate data breaches. Many states have responded by adopting data breach disclosure laws that require firms to notify consumers if their personal information has been lost or…

Outcomes associated with breach and fulfillment of the psychological contract of safety.

Science.gov (United States)

Walker, Arlene

2013-12-01

The study investigated the outcomes associated with breach and fulfillment of the psychological contract of safety. The psychological contract of safety is defined as the beliefs of individuals about reciprocal employer and employee safety obligations inferred from implicit or explicit promises. When employees perceive that safety obligations promised by the employer have not been met, a breach of the psychological contract occurs, termed employer breach of obligations. The extent to which employees fulfill their safety obligations to the employer is termed employee fulfillment of obligations. Structural equation modeling was used to test a model of safety that investigated the positive and negative outcomes associated with breach and fulfillment of the psychological contract of safety. Participants were 424 health care workers recruited from two hospitals in the State of Victoria, Australia. Following slight modification of the hypothesized model, a good fitting model resulted. Being injured in the workplace was found to lower perceptions of trust in the employer and increase perceptions of employer breach of safety obligations. Trust in the employer significantly influenced perceived employer breach of safety obligations such that lowered trust resulted in higher perceptions of breach. Perceptions of employer breach significantly impacted employee fulfillment of safety obligations with high perceptions of breach resulting in low employee fulfillment of obligations. Trust and perceptions of breach significantly influenced safety attitudes, but not safety behavior. Fulfillment of employee safety obligations significantly impacted safety behavior, but not safety attitudes. Implications of these findings for safety and psychological contract research are explored. A positive emphasis on social exchange relationships in organizations will have positive outcomes for safety climate and safety behavior. © 2013.

Evaluation of a dry process for conversion of U-AVLIS product to UF6. Milestone U361

International Nuclear Information System (INIS)

1992-05-01

A technical and engineering evaluation has been completed for a dry UF 6 production system to convert the product of an initial two-line U-AVLIS plant. The objective of the study has been to develop a better understanding of process design requirements, capital and operating costs, and demonstration requirements for this alternate process. This report summarizes the results of the study and presents various comparisons between the baseline and alternate processes, building on the information contained in UF 6 Product Alternatives Review Committee -- Final Report. It also provides additional information on flowsheet variations for the dry route which may warrant further consideration. The information developed by this study and conceptual design information for the baseline process will be combined with information to be developed by the U-AVLIS program and by industrial participants over the next twelve months to permit a further comparison of the baseline and alternate processes in terms of cost, risk, and compatibility with U-AVLIS deployment schedules and strategies. This comparative information will be used to make a final process flowsheet selection for the initial U-AVLIS plant by March 1993. The process studied is the alternate UF 6 production flowsheet. Process steps are (1) electron-beam distillation to reduce enriched product iron content from about 10 wt % or less, (2) hydrofluorination of the metal to UF 4 , (3) fluorination of UF 4 to UF 6 , (4) cold trap collection of the UF 6 product, (5) UF 6 purification by distillation, and (6) final blending and packaging of the purified UF 6 in cylinders. A preliminary system design has been prepared for the dry UF 6 production process based on currently available technical information. For some process steps, such information is quite limited. Comparisons have been made between this alternate process and the baseline plant process for UF 6 production

DUF6 Management

Science.gov (United States)

DUF6 Guide DU Uses DUF6 Management and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home » DUF6 Management Depleted UF6 Management An introduction to DOE's Depleted UF6 Management Program. The mission of the DOE's Depleted UF6 Management Program is to safely and efficiently manage the

The Comparing Options for Management: Patient-centered Results for Uterine Fibroids (COMPARE-UF) Registry: Rationale and Design.

Science.gov (United States)

Stewart, Elizabeth A; Lytle, Barbara L; Thomas, Laine; Wegienka, Ganesa R; Jacoby, Vanessa; Diamond, Michael P; Nicholson, Wanda K; Anchan, Raymond M; Venable, Sateria; Wallace, Kedra; Marsh, Erica E; Maxwell, George L; Borah, Bijan J; Catherino, William H; Myers, Evan R

2018-05-08

To design and establish a uterine fibroid (UF) registry based in the United States (US) to provide comparative effectiveness data regarding UF treatment. We report here the design and initial recruitment for the Comparing Options for Management: Patient-centered Results for Uterine Fibroids (COMPARE-UF) registry (Clinicaltrials.gov, NCT02260752), funded by the Agency for Healthcare Research and Quality (AHRQ) in collaboration with the-Patient-Centered Outcomes Research Institute (PCORI). COMPARE-UF is designed to help answer critical questions about treatment options for women with symptomatic UF. Women undergoing a procedure for UF (hysterectomy, myomectomy [abdominal, hysteroscopic, vaginal and laparoscopic/robotic], endometrial ablation, radiofrequency fibroid ablation, uterine artery embolization, magnetic resonance guided focused ultrasound or progestin-releasing intrauterine device insertion) at one of the COMPARE-UF sites are invited to participate in a prospective registry with three years follow-up for post-procedural outcomes. Enrolled participants provide annual follow-up through an online portal or through traditional phone contact. A central data abstraction center provides information obtained from imaging, operative or procedural notes and pathology reports. Women with uterine fibroids and other stakeholders are a key part of the COMPARE-UF registry and participate at all points from study design to dissemination of results. We built a network of nine clinical sites across the US with expertise in the care of women with UF to capture geographic, racial, ethnic and procedural diversity. Of the initial 2031 women enrolled in COMPARE-UF, 42% are self-identified as Black or African-American and 40% are age 40 years or younger with 16% of participants under age 35. Women undergoing myomectomy comprise the largest treatment group at 46% of all procedures with laparoscopic or robotic myomectomy comprising the largest subset of myomectomies at 19% of all

Values underlying perceptions of breach of the psychological contract

Directory of Open Access Journals (Sweden)

Leon Botha

2010-10-01

Research purpose: The study identifies the most important breaches and investigates which values underlie employee perceptions of breach of the psychological contract. It also addresses values that lead to employees interpreting incidents as breaches. Motivation for the study: The study calls on the fact that employees make inconsequential contributions to the terms of many formal employment contracts may imply that such contracts cannot be viewed as documents between equals. Research design, approach and method: The study identifies the most prominent breaches of the psychological contract and the values underlying the perceptions that violations have occurred. Main findings: The data revealed lack of promotion, poor interpersonal relations between colleagues and bad treatment by seniors as three main breaches of the contract, and social recognition, world of peace and sense of accomplishment as three dominant values that underlie perceptions of contract violation. Practical/managerial implications: The competent and intelligent manner in which lack of promotion is handled and communicated to employees is vital because it has implications for their willingness to contribute, their career prospects and their intention to stay in the organisation. Contribution/value-add: This research can serve as the basis for the development of survey or research instruments that are appropriate and relevant to the population.

The Significance of Mandatory Data Breach Warnings to Identity Crime

OpenAIRE

Eric Holm; Geraldine Mackenzie

2015-01-01

The relationship between data breaches and identity crime has been scarcely explored in current literature. However, there is an important relationship between the misuse of personal identification information and identity crime as the former is in many respects the catalyst for the latter. Data breaches are one of the ways in which this personal identification information is obtained by identity criminals, and thereby any response to data breaches is likely to impact the incidence of identit...

Integrating UF6 Cylinder RF Tracking With Continuous Load Cell Monitoring for Verifying Declared UF6 Feed and Withdrawal Operations Verifying Declared UF6 Feed and Withdrawal Operations

International Nuclear Information System (INIS)

Krichinsky, Alan M.; Miller, Paul; Pickett, Chris A.; Richardson, Dave; Rowe, Nathan C.; Whitaker, J. Michael; Younkin, James R.

2009-01-01

Oak Ridge National Laboratory is demonstrating the integration of UF6 cylinder tracking, using RF technology, with continuous load cell monitoring (CLCM) at mock UF6 feed and withdrawal (F and W) stations. CLCM and cylinder tracking are two of several continuous-monitoring technologies that show promise in providing integrated safeguards of F and W operations at enrichment plants. Integrating different monitoring technologies allows advanced, automated event processing to screen innocuous events thereby minimizing false alerts to independent inspectors. Traditionally, international inspectors rely on batch verification of material inputs and outputs derived from operator declarations and periodic on-site inspections at uranium enrichment plants or other nuclear processing facilities. Continuously monitoring F and W activities between inspections while providing filtered alerts of significant operational events will substantially increase the amount of valuable information available to inspectors thereby promising to enhance the effectiveness of safeguards and to improve efficiency in conducting on-site inspections especially at large plants for ensuring that all operations are declared.

Breach Risk Magnitude: A Quantitative Measure of Database Security.

Science.gov (United States)

Yasnoff, William A

2016-01-01

A quantitative methodology is described that provides objective evaluation of the potential for health record system breaches. It assumes that breach risk increases with the number of potential records that could be exposed, while it decreases when more authentication steps are required for access. The breach risk magnitude (BRM) is the maximum value for any system user of the common logarithm of the number of accessible database records divided by the number of authentication steps needed to achieve such access. For a one million record relational database, the BRM varies from 5.52 to 6 depending on authentication protocols. For an alternative data architecture designed specifically to increase security by separately storing and encrypting each patient record, the BRM ranges from 1.3 to 2.6. While the BRM only provides a limited quantitative assessment of breach risk, it may be useful to objectively evaluate the security implications of alternative database organization approaches.

The extreme risk of personal data breaches and the erosion of privacy

Science.gov (United States)

Wheatley, Spencer; Maillart, Thomas; Sornette, Didier

2016-01-01

Personal data breaches from organisations, enabling mass identity fraud, constitute an extreme risk. This risk worsens daily as an ever-growing amount of personal data are stored by organisations and on-line, and the attack surface surrounding this data becomes larger and harder to secure. Further, breached information is distributed and accumulates in the hands of cyber criminals, thus driving a cumulative erosion of privacy. Statistical modeling of breach data from 2000 through 2015 provides insights into this risk: A current maximum breach size of about 200 million is detected, and is expected to grow by fifty percent over the next five years. The breach sizes are found to be well modeled by an extremely heavy tailed truncated Pareto distribution, with tail exponent parameter decreasing linearly from 0.57 in 2007 to 0.37 in 2015. With this current model, given a breach contains above fifty thousand items, there is a ten percent probability of exceeding ten million. A size effect is unearthed where both the frequency and severity of breaches scale with organisation size like s0.6. Projections indicate that the total amount of breached information is expected to double from two to four billion items within the next five years, eclipsing the population of users of the Internet. This massive and uncontrolled dissemination of personal identities raises fundamental concerns about privacy.

An Analysis of Data Breach Notifications as Negative News

Science.gov (United States)

Veltsos, Jennifer R.

2012-01-01

Forty-six states require organizations to notify users when personally identifiable information has been exposed or when the organization's data security measures have been breached. This article describes a qualitative document analysis of 13 data breach notification templates from state and federal agencies. The results confirm much of the…

Just in Time Research: Data Breaches in Higher Education

Science.gov (United States)

Grama, Joanna

2014-01-01

This "Just in Time" research is in response to recent discussions on the EDUCAUSE Higher Education Information Security Council (HEISC) discussion list about data breaches in higher education. Using data from the Privacy Rights Clearinghouse, this research analyzes data breaches attributed to higher education. The results from this…

Uncertainties and constraints on breaching and their implications for flood loss estimation.

Science.gov (United States)

Muir Wood, Robert; Bateman, William

2005-06-15

Around the coasts of the southern North Sea, flood risk is mediated everywhere by the performance of natural and man-made flood defences. Under the conditions of extreme surge with tide water levels, the performance of the defences determines the extent of inland flooding. Sensitivity tests reveal the enormous increase in the volume of water that can pass through a defence once breaching is initiated, with a 1m reduction in sill elevation doubling the loss. Empirical observations of defence performance in major storm surges around the North Sea reveal some of the principal controls on breaching. For the same defence type, the maximum size and depth of a breach is a function of the integral of the hydraulic gradient across the defence, which is in turn determined by the elevation of the floodplain and the degree to which water can continue to flow inland away from the breach. The most extensive and lowest floodplains thereby "generate" the largest breaches. For surges that approach the crest height, the weaker the protection of the defence, the greater the number of breaches. Defence reinforcement reduces both the number and size of the breaches.

The applicability of fluoride volatility process to producing UF6 from yellow cake

International Nuclear Information System (INIS)

Xia Dechang

2005-01-01

The schematic diagrams producing UF 6 from yellow cake are showed in this paper. The characteristics and process improvements of the fluoride volatility process are explained. The applicability of the fluoride volatility process to producing UF 6 from yellow cake is discussed. (authors)

Evaluation of tecniques for controlling UF6 release clouds in the GAT environmental chamber

International Nuclear Information System (INIS)

Lux, C.J.

1982-01-01

Studies designed to characterize the reaction between UF 6 and atmospheric moisture, evaluate environmental variables of UF 6 cloud formation and ultimate cloud fate, and UF 6 release cloud control procedure have been conducted in the 1200 cu. ft. GAT environmental chamber. In earlier chamber experiments, 30 separate UF 6 release tests indicated that variations of atmospheric conditions and sample sizes had no significant effect on UO 2 F 2 particle size distribution, release cloud formation, or cloud settling rates. During the past year, numerous procedures have been evaluated for accelerating UF 6 cloud knockdown in a series of 37 environmental chamber releases. Knockdown procedures included: coarse water spray; air jet; steam spray (electrostatically charged and uncharged); carbon dioxide; Freon-12; fine water mist (uncharged); boric acid mist (charged and uncharged); and an ionized dry air stream. UF 6 hydrolysis cloud settling rates monitored by a laser/powermeter densitometer, indicated the relative effectiveness of various cloud knockdown techniques. Electrostatically charged boric acid/water mist, and electrostatically ionized dry air were both found to be very effective, knocking down the UO 2 F 2 release cloud particles in two to five minutes. Work to adapt these knockdown techniques for use under field conditions is continuing, taking into account recovery of the released uranium as well as nuclear criticality constraints

Run-beyond-clad-breach oxide testing in EBR-2

International Nuclear Information System (INIS)

Lambert, J.D.B.; Bottcher, J.H.; Strain, R.V.; Gross, K.C.; Lee, M.J.; Webb, J.P.; Colburn, R.P.; Ukai, S.; Nomura, S.; Odo, T.; Shikakura, S.

1990-01-01

Fourteen tests sponsored by the US and Japan were used to study reliability of breached LMR oxide fuel pins during continued operation in EBR-II for a range of conditions and parameters. The fuel-sodium reaction product governed pin behavior. It extended primary breaches by swelling and promoted secondary failures, yet it inhibited loss of fuel and fission products and enhanced release of delayed neutrons used in monitoring breach condition. Fission gas and cesium, the main contaminants from failures, could be adequately controlled. This positive EBR-II experience suggested that limited operation with failed fuel may be feasible in commercial LMR's. 16 refs., 14 figs., 4 tabs

Tortious Interference with Contract versus "Efficient" Breach: Theory and Empirical Evidence.

OpenAIRE

McChesney, Fred S

1999-01-01

Tortious interference is bothersome, normatively and positively, to scholars espousing the economic model of "efficient breach" of contract because it penalizes third-party inducements to breach. Scholars nonetheless find innovative second-best arguments to justify the coexistence of tortious interference with "efficient" breach. This article shows normatively why tortious interference would be part of a first-best legal system. Tortious interference provides property protection to contract r...

Challenges dealing with depleted uranium in Germany - Reuse or disposal

International Nuclear Information System (INIS)

Moeller, Kai D.

2007-01-01

During enrichment large amounts of depleted Uranium are produced. In Germany every year 2.800 tons of depleted uranium are generated. In Germany depleted uranium is not classified as radioactive waste but a resource for further enrichment. Therefore since 1996 depleted Uranium is sent to ROSATOM in Russia. However it still has to be dealt with the second generation of depleted Uranium. To evaluate the alternative actions in case a solution has to be found in Germany, several studies have been initiated by the Federal Ministry of the Environment. The work that has been carried out evaluated various possibilities to deal with depleted uranium. The international studies on this field and the situation in Germany have been analyzed. In case no further enrichment is planned the depleted uranium has to be stored. In the enrichment process UF 6 is generated. It is an international consensus that for storage it should be converted to U 3 O 8 . The necessary technique is well established. If the depleted Uranium would have to be characterized as radioactive waste, a final disposal would become necessary. For the planned Konrad repository - a repository for non heat generating radioactive waste - the amount of Uranium is limited by the licensing authority. The existing license would not allow the final disposal of large amounts of depleted Uranium in the Konrad repository. The potential effect on the safety case has not been roughly analyzed. As a result it may be necessary to think about alternatives. Several possibilities for the use of depleted uranium in the industry have been identified. Studies indicate that the properties of Uranium would make it useful in some industrial fields. Nevertheless many practical and legal questions are open. One further option may be the use as shielding e.g. in casks for transport or disposal. Possible techniques for using depleted Uranium as shielding are the use of the metallic Uranium as well as the inclusion in concrete. Another

Reactions of aluminum with uranium fluorides and oxyfluorides

Energy Technology Data Exchange (ETDEWEB)

Leitnaker, J.M.; Nichols, R.W.; Lankford, B.S. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31

Every 30 to 40 million operating hours a destructive reaction is observed in one of the {approximately}4000 large compressors that move UF{sub 6} through the gaseous diffusion plants. Despite its infrequency, such a reaction can be costly in terms of equipment and time. Laboratory experiments reveal that the presence of moderate pressures of UF{sub 6} actually cools heated aluminum, although thermodynamic calculations indicate the potential for a 3000-4000{degrees}C temperature rise. Within a narrow and rather low (<100 torr; 1 torr = 133.322 Pa) pressure range, however, the aluminum is seen to react with sufficient heat release to soften an alumina boat. Three things must occur in order for aluminum to react vigorously with either UF{sub 6} or UO{sub 2}F{sub 2}. 1. An initiating source of heat must be provided. In the compressors, this source can be friction, permitted by disruption of the balance of the large rotating part or by creep of the aluminum during a high-temperature treatment. In the absence of this heat source, compressors have operated for 40 years in UF{sub 6} without significant reaction. 2. The film protecting the aluminum must be breached. Melting (of UF{sub 5} at 620 K or aluminum at 930 K) can cause such a breach in laboratory experiments. In contrast, holding Al samples in UF{sub 6} at 870 K for several hours produces only moderate reaction. Rubbing in the cascade can undoubtedly breach the protective film. 3. Reaction products must not build up and smother the reaction. While uranium products tend to dissolve or dissipate in molten aluminum, AIF{sub 3} shows a remarkable tendency to surround and hence protect even molten aluminum. Hence the initial temperature rise must be rapid and sufficient to move reactants into a temperature region in which products are removed from the reaction site.

Translation and validation of the Uterine Fibroid Symptom and Quality of Life (UFS-QOL questionnaire for the Brazilian Portuguese language

Directory of Open Access Journals (Sweden)

Luiz Gustavo Oliveira Brito

2017-03-01

Full Text Available ABSTRACT CONTEXT AND OBJECTIVE: Uterine fibroids (UF, also known as leiomyomas, are the most prevalent gynecological tumors. The Uterine Fibroid Symptoms and Quality of Life (UFS-QOL is the only specific questionnaire that assesses symptom intensity and quality-of-life issues for women with symptomatic UF; however, it only exists in the English language. Thus, we aimed to translate and culturally validate the UFS-QOL questionnaire for the Brazilian Portuguese language. DESIGN AND SETTING: Cross-sectional study, Department of Gynecology and Obstetrics, FMRP-USP. METHODS: 113 patients with UF (case group and 55 patients without UF (control group were interviewed using the UFS-QOL questionnaire after translation and cultural adaptation. The Short Form-36 questionnaire was used as a control. Demographic and psychometric variables were analyzed. RESULTS: Women with UF presented higher mean age, body mass index, weight, parity and comorbidities than the control group (P < 0.05. The most prevalent complaints were abnormal uterine bleeding (93.8%, pelvic pain (36.3% and extrinsic compression (10.6% and these presented adequate construct validity regarding UFS-QOL severity (P < 0.05. The UFS-QOL questionnaire presented good internal consistency regarding symptom severity and quality-of-life-related domains (intraclass correlation coefficient, ICC = 0.82/0.88. Structural validity presented correlation coefficients ranging from 0.59 to 0.91. Test-retest comparison did not show differences among the UFS-QOL subscales. After treatment, women with UF presented improvements on all subscales. CONCLUSION: The UFS-QOL questionnaire presented adequate translation to the Brazilian Portuguese language, with good internal consistency, discriminant validity, construct validity, structural validity and responsiveness, along with adequate test-retest results.

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...

Criticality safety review of 2 1/2-, 10-, and 14-ton UF6 cylinders

International Nuclear Information System (INIS)

Broadhead, B.L.

1991-10-01

Currently, UF 6 cylinders designed to contain 2 1/2 tons of UF 6 are classified as Fissile Class 2 packages with a transport index (TI) of 5 for the purpose of transportation. The 10-ton UF 6 cylinders are classified as Fissile Class 1 with no TI assigned for transportation. The 14-ton cylinders, although not certified for transport with enrichments greater than 1 wt % because they have no approved overpack, can be used in on-site operations for enrichments greater than 1 wt %. The maximum 235 U enrichments for these cylinders are 5.0 wt % for the 2 1/2-ton cylinder and 4.5 wt % for the 10- and 14-ton cylinders. This work reviews the suitability for reclassification of the 2 1/2-ton UF 6 packages as Fissile Class 1 with a maximum 235 U enrichment of 5 wt %. Additionally, the 10- and 14-ton cylinders are reviewed to address a change in maximum 235 U enrichment from 4.5 to 5 wt %. Based on this evaluation, the 2 1/2-ton UF 6 cylinders meet the 10 CFR.71 criteria for Fissile Class 1 packages, and no TI is needed for criticality safety purposes; however, a TI may be required based on radiation from the packages. Similarly, the 10- and 14-ton UF 6 packages appear acceptable for a maximum enrichment rating change to 5 wt % 235 U. 11 refs., 13 figs., 7 tabs

Scenarios and analytical methods for UF6 releases at NRC-licensed fuel cycle facilities

International Nuclear Information System (INIS)

Siman-Tov, M.; Dykstra, J.; Holt, D.D.; Huxtable, W.P.; Just, R.A.; Williams, W.R.

1984-06-01

This report identifies and discusses potential scenarios for the accidental release of UF 6 at NRC-licensed UF 6 production and fuel fabrication facilities based on a literature review, site visits, and DOE enrichment plant experience. Analytical tools needed for evaluating source terms for such releases are discussed, and the applicability of existing methods is reviewed. Accident scenarios are discussed under the broad headings of cylinder failures, UF 6 process system failures, nuclear criticality events, and operator errors and are categorized by location, release source, phase of UF 6 prior to release, release flow characteristics, release causes, initiating events, and UF 6 inventory at risk. At least three types of releases are identified for further examination: (1) a release from a liquid-filled cylinder outdoors, (2) a release from a pigtail or cylinder in a steam chest, (3) an indoor release from either (a) a pigtail or liquid-filled cylinder or (b) other indoor source depending on facility design and operating procedures. Indoor release phenomena may be analyzed to determine input terms for a ventilation model by using a time-dependent homogeneous compartment model or a more complex hydrodynamic model if time-dependent, spatial variations in concentrations, temperature, and pressure are important. Analytical tools for modeling directed jets and explosive releases are discussed as well as some of the complex phenomena to be considered in analyzing UF 6 releases both indoors and outdoors

Determination of UO2 little quantity in UF4 by X-rays diffraction

International Nuclear Information System (INIS)

Costa, M.I.; Sato, I.M.; Imakuma, K.

1977-01-01

In the fluorination process, the final product UF 4 contain different levels of UO 2 as a contaminant. A routine method for quantitative analysis by x-ray diffraction has been developed. Standard curves have been plotted using mixtures of UO 2 /UF 4 with measures of intensity of (III) peak of UO 2 by the step scanning process. The integrated intensity versus UO 2 concentration curves present a linear behavior in the range from 0 to 4%. A good reprodutibility of measuring process has been observed through statistical analysis which permits to determine low fractions of UO 2 in UF 4 with +- 0,08% of accuracy [pt

Psychological contract breaches, organizational commitment, and innovation-related behaviors: a latent growth modeling approach.

Science.gov (United States)

Ng, Thomas W H; Feldman, Daniel C; Lam, Simon S K

2010-07-01

This study examined the relationships among psychological contract breaches, organizational commitment, and innovation-related behaviors (generating, spreading, implementing innovative ideas at work) over a 6-month period. Results indicate that the effects of psychological contract breaches on employees are not static. Specifically, perceptions of psychological contract breaches strengthened over time and were associated with decreased levels of affective commitment over time. Further, increased perceptions of psychological contract breaches were associated with decreases in innovation-related behaviors. We also found evidence that organizational commitment mediates the relationship between psychological contract breaches and innovation-related behaviors. These results highlight the importance of examining the nomological network of psychological contract breaches from a change perspective.

Cost-effectiveness of safety measures to reduce public risk associated with the transportation of UF6 by truck and trains

International Nuclear Information System (INIS)

Hubert, Philippe; Pages, Pierre

1989-01-01

The present case study deals with the problem of uranium hexafluoride transportation by truck and train. It consists of a probabilistic risk assessment of the potential hazards to the public that can arise from the traffic that will take place in France in 1990. The specificity of UF 6 is that it presents both chemical and radiological hazards. But, whatever the transported material, road traffic entails a risk of its own. Thus three kinds of risks are assessed for natural, depleted and enriched uranium hexafluoride. These assessments are the basis of a cost-effectiveness analysis which deals with such safety measures as using a protective overpack, avoiding populated areas and escorting the trucks

Analyses of postulated accidental releases of UF6 inside process buildings

International Nuclear Information System (INIS)

Oliveira Neto, Jose Messias de; Nunes, Beatriz Guimaraes; Dias, Cristiane

2009-01-01

Uranium Hexafluoride is a material used in the various processes which comprise the front end of the nuclear fuel cycle (conversion, enrichment and fuel fabrication). Confinement of UF 6 is a very important safety requirement since this material is highly reactive and presents safety hazards to humans. The present paper discusses the safety relevant aspects of accidental releases of UF 6 inside process confinement buildings. Postulated accidental scenarios are analyzed and their consequences evaluated. Implant releases rates are estimated using computer code predictions. A time dependent homogeneous compartment model is used to predict concentrations of UF 6 , hydrogen fluoride and uranyl fluoride inside a confinement building, as well as to evaluate source terms released to the atmosphere. These source terms can be used as input to atmospheric dispersion models to evaluate consequences to the environment. The results can also be used to define adequate protective measures for emergency situations. (author)

The Cryptographic Implications of the LinkedIn Data Breach

OpenAIRE

Gune, Aditya

2017-01-01

Data security and personal privacy are difficult to maintain in the Internet age. In 2012, professional networking site LinkedIn suffered a breach, compromising the login of over 100 million accounts. The passwords were cracked and sold online, exposing the authentication credentials millions of users. This manuscript dissects the cryptographic failures implicated in the breach, and explores more secure methods of storing passwords.

Evaluation of a dry process for conversion of U-AVLIS product to UF{sub 6}. Milestone U361

Energy Technology Data Exchange (ETDEWEB)

NONE

1992-05-01

A technical and engineering evaluation has been completed for a dry UF{sub 6} production system to convert the product of an initial two-line U-AVLIS plant. The objective of the study has been to develop a better understanding of process design requirements, capital and operating costs, and demonstration requirements for this alternate process. This report summarizes the results of the study and presents various comparisons between the baseline and alternate processes, building on the information contained in UF{sub 6} Product Alternatives Review Committee -- Final Report. It also provides additional information on flowsheet variations for the dry route which may warrant further consideration. The information developed by this study and conceptual design information for the baseline process will be combined with information to be developed by the U-AVLIS program and by industrial participants over the next twelve months to permit a further comparison of the baseline and alternate processes in terms of cost, risk, and compatibility with U-AVLIS deployment schedules and strategies. This comparative information will be used to make a final process flowsheet selection for the initial U-AVLIS plant by March 1993. The process studied is the alternate UF{sub 6} production flowsheet. Process steps are (1) electron-beam distillation to reduce enriched product iron content from about 10 wt % or less, (2) hydrofluorination of the metal to UF{sub 4}, (3) fluorination of UF{sub 4} to UF{sub 6}, (4) cold trap collection of the UF{sub 6} product, (5) UF{sub 6} purification by distillation, and (6) final blending and packaging of the purified UF{sub 6} in cylinders. A preliminary system design has been prepared for the dry UF{sub 6} production process based on currently available technical information. For some process steps, such information is quite limited. Comparisons have been made between this alternate process and the baseline plant process for UF{sub 6} production.

A Simple model for breach formation by overtopping

Energy Technology Data Exchange (ETDEWEB)

Trousseau, P. [Hydro-Quebec, Montreal, PQ (Canada); Kahawita, R. [Ecole Polytechnique, Montreal, PQ (Canada)

2006-07-01

Failures in earth or rockfill dams are often caused by overtopping of the crest, leading to initiation and uncontrolled progression of a breach. Overtopping may occur because of large inflows into the reservoir caused by excessive rainfall or by the failure of an upstream dam that causes a large volume of water to suddenly arrive at the downstream reservoir thus rapidly exceeding the storage and spillway evacuation capacity. Breach formation in a rockfill or earthfill dike due to overtopping of the crest is a complex process as it involves interaction between the hydraulics of the flow and the erosion characteristics of the fill material. This paper presented a description and validation of a simple parametric model for breach formation due to overtopping. A study was conducted to model, as closely as possible, the physical processes involved within the restriction of the simplified analysis. The objective of the study was to predict the relevant timescales for the phenomenon leading to a prediction of the outflow hydrograph. The model has been validated on the Oros dam failure in Brazil as well as on embankment tests conducted at Rosvatn, Norway. It was concluded that the major impediment to the development of breach erosion models for use as predictive tools is in the characterization of the erosion behaviour. 19 refs., 2 tabs., 9 figs.

Decrease the Number of Glovebox Glove Breaches and Failures

Energy Technology Data Exchange (ETDEWEB)

Hurtle, Jackie C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2013-12-24

Los Alamos National Laboratory (LANL) is committed to the protection of the workers, public, and environment while performing work and uses gloveboxes as engineered controls to protect workers from exposure to hazardous materials while performing plutonium operations. Glovebox gloves are a weak link in the engineered controls and are a major cause of radiation contamination events which can result in potential worker exposure and localized contamination making operational areas off-limits and putting programmatic work on hold. Each day of lost opportunity at Technical Area (TA) 55, Plutonium Facility (PF) 4 is estimated at $1.36 million. Between July 2011 and June 2013, TA-55-PF-4 had 65 glovebox glove breaches and failures with an average of 2.7 per month. The glovebox work follows the five step safety process promoted at LANL with a decision diamond interjected for whether or not a glove breach or failure event occurred in the course of performing glovebox work. In the event that no glove breach or failure is detected, there is an additional decision for whether or not contamination is detected. In the event that contamination is detected, the possibility for a glove breach or failure event is revisited.

Review of models used for determining consequences of UF6 release: Model evaluation report. Volume 2

International Nuclear Information System (INIS)

Nair, S.K.; Chambers, D.B.; Park, S.H.; Radonjic, Z.R.; Coutts, P.T.; Lewis, C.J.; Hammonds, J.S.; Hoffman, F.O.

1997-11-01

Three uranium hexafluoride-(UF 6 -) specific models--HGSYSTEM/UF 6 , Science Application International Corporation, and RTM-96; three dense-gas models--DEGADIS, SLAB, and the Chlorine Institute methodology; and one toxic chemical model--AFTOX--are evaluated on their capabilities to simulate the chemical reactions, thermodynamics, and atmospheric dispersion of UF 6 released from accidents at nuclear fuel-cycle facilities, to support Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis. These models are also evaluated for user-friendliness and for quality assurance and quality control features, to ensure the validity and credibility of the results. Model performance evaluations are conducted for the three UF 6 -specific models, using field data on releases of UF 6 and other heavy gases. Predictions from the HGSYSTEM/UF 6 and SAIC models are within an order of magnitude of the field data, but the SAIC model overpredicts beyond an order of magnitude for a few UF 6 -specific data points. The RTM-96 model provides overpredictions within a factor of 3 for all data points beyond 400 m from the source. For one data set, however, the RTM-96 model severely underpredicts the observations within 200 m of the source. Outputs of the models are most sensitive to the meteorological parameters at large distances from the source and to certain source-specific and meteorological parameters at distances close to the source. Specific recommendations are being made to improve the applicability and usefulness of the three models and to choose a specific model to support the intended analyses. Guidance is also provided on the choice of input parameters for initial dilution, building wake effects, and distance to completion of UF 6 reaction with water

"Financial Emergency" and the Faculty Furlough: A Breach of Contract.

Science.gov (United States)

Richards, Mary Sanders

1984-01-01

The power of the university to breach faculty contracts in order to meet its temporary cash-flow problems and the rights of faculty when this breach occurs are discussed. To avoid litigation, a university must have established internal guidelines which can be incorporated into an employment contract. (MLW)

Using Vignette Methodology to research the process of breach comparatively

NARCIS (Netherlands)

Boone, M.M.; Beyens, K.; Maguire, N.; Laurinavicius, A.; Persson, A.

2015-01-01

Comparative research related to any aspect of the process of breach in either the pre-trial, sentencing or release phases is relatively rare. Comparative studies of decision making in the specific context of breach process are particularly lacking. One reason for the dearth of research in this area

Handling of UF6 in U.S. gaseous diffusion plants

International Nuclear Information System (INIS)

Legeay, A.J.

1978-01-01

A comprehensive systems analysis of UF 6 handling has been made in the three U.S. gaseous diffusion plants and has resulted in a significant impact on the equipment design and the operating procedures of these facilities. The equipment, facilities, and industrial practices in UF 6 handling operations as they existed in the early 1970's are reviewed with particular emphasis placed on the changes which have been implemented. The changes were applied to the systems and operating methods which evolved from the design, startup, and operation of the Oak Ridge Gaseous Diffusion Plant in 1945

Reasons for Picture Archiving and Communication System (PACS data security breaches: Intentional versus non-intentional breaches

Directory of Open Access Journals (Sweden)

Tintswalo Brenda Mahlaola

2016-12-01

Conclusion: Our study supports previous findings that, in the absence of guidelines, most security breaches were non-intentional acts committed due to ignorance. Of concern are incidents in which sensitive information was intentionally shared via social media.

How to Survive a Data Breach

CERN Document Server

Mitchell, Stewart

2009-01-01

This is the downloadable version of this new pocket guide which provides essential support for organisations who would like to have a tried and tested procedure in place for dealing with data breaches.

Cost-effectiveness of safety measures to reduce public risk associated with the transportation of UF{sub 6} by truck and trains

Energy Technology Data Exchange (ETDEWEB)

Hubert, Philippe; Pages, Pierre

1989-08-01

The present case study deals with the problem of uranium hexafluoride transportation by truck and train. It consists of a probabilistic risk assessment of the potential hazards to the public that can arise from the traffic that will take place in France in 1990. The specificity of UF{sub 6} is that it presents both chemical and radiological hazards. But, whatever the transported material, road traffic entails a risk of its own. Thus three kinds of risks are assessed for natural, depleted and enriched uranium hexafluoride. These assessments are the basis of a cost-effectiveness analysis which deals with such safety measures as using a protective overpack, avoiding populated areas and escorting the trucks.

The determination of UO2 and UF4 in fused fluoride salts

International Nuclear Information System (INIS)

Batiste, D.J.; Lee, D.A.

1989-01-01

The determination of uranium oxide solubilities in fused fluoride salts is important in the electrolytic preparation of uranium metal. This project was initiated to develop a method for the determination of UO 2 separately from UF 4 in UF 4 -CaF 2 -LiF fused salts. Previous methods used for the determination of UO 2 in fused fluoride salts involved inert gas fusions where oxygen was liberated as CO 2 , and hydrofluorination where oxygen was released as H 2 O; but the special equipment used for these procedures was no longer available. These methods assumed that all of the oxygen liberated was due to UO 2 and does not consider impurities from reagents and other oxygen sources that amount to a bias of approximately 0.3 wt %. This titrimetric method eliminates the bias by selectively extracting the UF 4 with a Na 2 EDTA-H 3 BO 3 solution. The remaining uranium oxide residue is treated and titrated gravimetrically to a potentiometric endpoint with NBS standard K 2 Cr 2 O 7 . An aliquot of the Na 2 EDTA-H 3 BO 3 extract is also titrated gravimetrically to a potentiometric endpoint, this uranium component is determined and calculated as UF 4 . 4 refs., 2 figs., 2 tabs

A laser profilometry technique for monitoring fluvial dike breaching in laboratory experiments

Science.gov (United States)

Dewals, Benjamin; Rifai, Ismail; Erpicum, Sébastien; Archambeau, Pierre; Violeau, Damien; Pirotton, Michel; El kadi Abderrezzak, Kamal

2017-04-01

A challenging aspect for experimental modelling of fluvial dike breaching is the continuous monitoring of the transient breach geometry. In dam breaching cases induced by flow overtopping over the whole breach crest (plane erosion), a side view through a glass wall is sufficient to monitor the breach formation. This approach can be extended for 3D dam breach tests (spatial erosion) if the glass wall is located along the breach centreline. In contrast, using a side view does not apply for monitoring fluvial dike breaching, because the breach is not symmetric in this case. We present a non-intrusive, high resolution technique to record the breach development in experimental models of fluvial dikes by means of a laser profilometry (Rifai et al. 2016). Most methods used for monitoring dam and dike breaching involve the projection of a pattern (fringes, grid) on the dam or dike body and the analysis of its deformation on images recorded during the breaching (e.g., Pickert et al. 2011, Frank and Hager 2014). A major limitation of these methods stems from reflection on the water surface, particularly in the vicinity of the breach where the free surface is irregular and rippled. This issue was addressed by Spinewine et al. (2004), who used a single laser sheet so that reflections on the water surface were strongly limited and did not hamper the accurate processing of each image. We have developed a similar laser profilometry technique tailored for laboratory experiments on fluvial dike breaching. The setup is simple and relatively low cost. It consists of a digital video camera (resolution of 1920 × 1080 pixels at 60 frames per second) and a swiping red diode 30 mW laser that enables the projection of a laser sheet over the dike body. The 2D image coordinates of each deformed laser profile incident on the dike are transformed into 3D object coordinates using the Direct Linear Transformation (DLT) algorithm. All 3D object coordinates computed over a swiping cycle of the

Reactions to psychological contract breaches and organizational citizenship behaviours: An experimental manipulation of severity.

Science.gov (United States)

Atkinson, Theresa P; Matthews, Russell A; Henderson, Alexandra A; Spitzmueller, Christiane

2018-01-30

Grounded in affective events theory, we investigated the effects of experimentally manipulated psychological contract breaches on participants' feelings of violation, subsequent perceptions of psychological contract strength, and organizational citizenship behaviours in a sample of working adults. Results support previous findings that pre-existing relational psychological contract strength interacts with severity of unmet promises or expectations. Specifically, individuals with high relational contracts who experience low severity of unmet promises/expectations have the lowest breach perceptions, whereas individuals with high relational contracts who experience more severe levels unmet promises/expectations experience the highest level of breach perceptions. Results also support the concept of a breach spiral in that prior perceptions of breach led to an increased likelihood of subsequent perceptions of breach following the experimental manipulation. Furthermore, consistent with affective events theory, results support the argument that a psychological contract breach's effect on specific organizational citizenship behaviours is mediated by feelings of violation and the reassessment of relational contracts. These effects were present even after controlling for the direct effects of the manipulated severity of unmet promises/expectations. Copyright © 2018 John Wiley & Sons, Ltd.

HGSYSTEMUF6, Simulating Dispersion Due to Atmospheric Release of Uranium Hexafluoride (UF6)

International Nuclear Information System (INIS)

Hanna, G; Chang, J.C.; Zhang, J.X.; Bloom, S.G.; Goode, W.D. Jr; Lombardi, D.A.; Yambert, M.W.

2001-01-01

1 - Description of program or function: HGSYSTEMUF6 is a suite of models designed for use in estimating consequences associated with accidental, atmospheric release of Uranium Hexafluoride (UF 6 ) and its reaction products, namely Hydrogen Fluoride (HF), and other non-reactive contaminants which are either negatively, neutrally, or positively buoyant. It is based on HGSYSTEM Version 3.0 of Shell Research LTD., and contains specific algorithms for the treatment of UF 6 chemistry and thermodynamics. HGSYSTEMUF6 contains algorithms for the treatment of dense gases, dry and wet deposition, effects due to the presence of buildings (canyon and wake), plume lift-off, and the effects of complex terrain. The models components of the suite include (1) AEROPLUME/RK, used to model near-field dispersion from pressurized two-phase jet releases of UF6 and its reaction products, (2) HEGADAS/UF6 for simulating dense, ground based release of UF 6 , (3) PGPLUME for simulation of passive, neutrally buoyant plumes (4) UF6Mixer for modeling warm, potentially reactive, ground-level releases of UF 6 from buildings, and (5) WAKE, used to model elevated and ground-level releases into building wake cavities of non-reactive plumes that are either neutrally or positively buoyant. 2 - Methods: The atmospheric release and transport of UF 6 is a complicated process involving the interaction between dispersion, chemical and thermodynamic processes. This process is characterized by four separate stages (flash, sublimation, chemical reaction entrainment and passive dispersion) in which one or more of these processes dominate. The various models contained in the suite are applicable to one or more of these stages. For example, for modeling reactive, multiphase releases of UF 6 , the AEROPLUME/RK component employs a process-splitting scheme which numerically integrates the differential equations governing dispersion, UF 6 chemistry, and thermodynamics. This algorithm is based on the assumption that

Sodium erosion of boron carbide from breached absorber pins

International Nuclear Information System (INIS)

Basmajian, J.A.; Baker, D.E.

1981-03-01

The purpose of the irradiation experiment was to provide an engineering demonstration of the irradiation behavior of breached boron carbide absorber pins. By building defects into the cladding of prototypic absorber pins, and performing the irradiation under typical FFTF operating conditions, a qualitative assessment of the consequences of a breach was achieved. Additionally, a direct comparison of pin behavior with that of the ex-reactor test could be made

Testing of one-inch UF{sub 6} cylinder valves under simulated fire conditions

Energy Technology Data Exchange (ETDEWEB)

Elliott, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Accurate computational models which predict the behavior of UF{sub 6} cylinders exposed to fires are required to validate existing firefighting and emergency response procedures. Since the cylinder valve is a factor in the containment provided by the UF{sub 6} cylinder, its behavior under fire conditions has been a necessary assumption in the development of such models. Consequently, test data is needed to substantiate these assumptions. Several studies cited in this document provide data related to the behavior of a 1-inch UF{sub 6} cylinder valve in fire situations. To acquire additional data, a series of tests were conducted at the Paducah Gaseous Diffusion Plant (PGDP) under a unique set of test conditions. This document describes this testing and the resulting data.

Rupture of Model 48Y UF6 cylinder and release of uranium hexafluoride. Cylinder overfill, March 12-13, 1986. Investigation of a failed UF6 shipping container. Volume 2

International Nuclear Information System (INIS)

1986-06-01

NUREG-1179, Volume 1, reported on the rupture of a Model 48Y uranium hexafluoride (UF 6 ) cylinder and the subsequent release of UF 6 . At the time of publication, a detailed metallurgical examination of the damaged cylinder was under way and results were not available. Subsequent to the publication of Volume 1, a second incident occurred at the Sequoyah Fuels Corporation facility. On March 13, 1986, a Model 48X cylinder was overfilled during a special one-time draining procedure; however, no release of UF 6 occurred. An Augmented Investigation Team investigated this second incident. This report, NUREG-1179, Volume 2, presents the findings made by the Augmented Investigation Team of the March 13 incident and the report of the detailed metallurgical examination conducted by Battelle Columbus Division of the cylinder damaged on January 4, 1986

The A to Z of healthcare data breaches.

Science.gov (United States)

Kobus, Theodore J

2012-01-01

There currently exists a myriad of privacy laws that impact a healthcare entity, including more than 47 notification laws that require notification when a data breach occurs, as well as the breach notification requirements of the Health Information Technology for Economic and Clinical Health Act. Given the plethora of issues a healthcare entity faces, there are certain principles that can be built into an organization's philosophy that will comply with the law and help protect it from reputational harm. © 2012 American Society for Healthcare Risk Management of the American Hospital Association.

Identifying psychological contract breaches to guide improvements in faculty recruitment, retention, and development.

Science.gov (United States)

Peirce, Gretchen L; Desselle, Shane P; Draugalis, JoLaine R; Spies, Alan R; Davis, Tamra S; Bolino, Mark

2012-08-10

To identify pharmacy faculty members' perceptions of psychological contract breaches that can be used to guide improvements in faculty recruitment, retention, and development. A list of psychological contract breaches was developed using a Delphi procedure involving a panel of experts assembled through purposive sampling. The Delphi consisted of 4 rounds, the first of which elicited examples of psychological contract breaches in an open-ended format. The ensuing 3 rounds consisting of a survey and anonymous feedback on aggregated group responses. Usable responses were obtained from 11 of 12 faculty members who completed the Delphi procedure. The final list of psychological contract breaches included 27 items, after modifications based on participant feedback in subsequent rounds. The psychological contract breach items generated in this study provide guidance for colleges and schools of pharmacy regarding important aspects of faculty recruitment, retention, and development.

Bouncing back from psychological contract breach: How commitment recovers over time

NARCIS (Netherlands)

Solinger, O.N.; Hofmans, J.; Bal, P.M.; Jansen, P.G.W.

2016-01-01

The post-violation model of the psychological contract outlines four ways in which a psychological contract may be resolved after breach (i.e., psychological contract thriving, reactivation, impairment, and dissolution). To explore the implications of this model for post-breach restoration of

Modeling and analyses of postulated UF6 release accidents in gaseous diffusion plant

International Nuclear Information System (INIS)

Kim, S.H.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W.; Carter, J.C.; Dyer, R.H.

1995-10-01

Computer models have been developed to simulate the transient behavior of aerosols and vapors as a result of a postulated accident involving the release of uranium hexafluoride (UF 6 ) into the process building of a gaseous diffusion plant. UF 6 undergoes an exothermic chemical reaction with moisture (H 2 O) in the air to form hydrogen fluoride (HF) and radioactive uranyl fluoride (UO 2 F 2 ). As part of a facility-wide safety evaluation, this study evaluated source terms consisting of UO 2 F 2 as well as HF during a postulated UF 6 release accident in a process building. In the postulated accident scenario, ∼7900 kg (17,500 lb) of hot UF 6 vapor is released over a 5 min period from the process piping into the atmosphere of a large process building. UO 2 F 2 mainly remains as airborne-solid particles (aerosols), and HF is in a vapor form. Some UO 2 F 2 aerosols are removed from the air flow due to gravitational settling. The HF and the remaining UO 2 F 2 are mixed with air and exhausted through the building ventilation system. The MELCOR computer code was selected for simulating aerosols and vapor transport in the process building. MELCOR model was first used to develop a single volume representation of a process building and its results were compared with those from past lumped parameter models specifically developed for studying UF 6 release accidents. Preliminary results indicate that MELCOR predicted results (using a lumped formulation) are comparable with those from previously developed models

Obtaining of uranium tetrafluoride UF4 by electrodialysis reactive from uranium concentrates

International Nuclear Information System (INIS)

Munoz Lay, Danny Mauricio

2014-01-01

The generation of uranium fuels has always been a topic worldwide. The uranium fuel manufacturing base is made under very strict parameters of radiological and industrial safety, being a stage called 'nuclear fuel cycle'. In Chile, it is done constant research for fuels. This report focuses primarily on participating in such research; mainly in the production of uranium tetrafluoride (UF 4 ) .The tetrafluoride production is very crucial for the nuclear fuel industry. Its production varies from precipitation in stirred conditions to electrolysis in mercury. However, both processes has shortcomings either in performance and environmental pollution, which is why it is proposed a new method of production based on a friendly process to the environment and easier to operate, the reactive electrodialysis (RED). Electrodialysis is a hybrid reactive process of separation by membranes, cationic and / or anionic, namely, ionic species. In the process, ions are induced to move by an electric potential applied and separated by these membranes, a highly selective physical barrier which allows passage of ions with certain charge, and prevents the passage of oppositely charged ions. And in turn, it is reactive because it forces a chemical reaction, redox, to obtain uranium tetrafluoride (UF 4 ). The results of these experiments show that by reactive electrodialysis, NH 4 UF 5 deposits were obtained. However, calcinating the NH 4 UF 5 to 450 o C, it decomposes to obtain uranium tetrafluoride, UF 4 . The best working conditions were obtained with an electric current of 0.5 (A), 41 o C and a flow of 16 (ml / s) of the electrolyte. It was possible to obtain 5,995 (g) to 3 (h), giving a current efficiency of 71.42%. In turn, working at high temperatures and flow recirculation is possible to operate with a potential difference of 1.7 (V)

Review of models used for determining consequences of UF{sub 6} release: Model evaluation report. Volume 2

Energy Technology Data Exchange (ETDEWEB)

Nair, S.K.; Chambers, D.B.; Park, S.H.; Radonjic, Z.R.; Coutts, P.T.; Lewis, C.J.; Hammonds, J.S.; Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis

1997-11-01

Three uranium hexafluoride-(UF{sub 6}-) specific models--HGSYSTEM/UF{sub 6}, Science Application International Corporation, and RTM-96; three dense-gas models--DEGADIS, SLAB, and the Chlorine Institute methodology; and one toxic chemical model--AFTOX--are evaluated on their capabilities to simulate the chemical reactions, thermodynamics, and atmospheric dispersion of UF{sub 6} released from accidents at nuclear fuel-cycle facilities, to support Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis. These models are also evaluated for user-friendliness and for quality assurance and quality control features, to ensure the validity and credibility of the results. Model performance evaluations are conducted for the three UF{sub 6}-specific models, using field data on releases of UF{sub 6} and other heavy gases. Predictions from the HGSYSTEM/UF{sub 6} and SAIC models are within an order of magnitude of the field data, but the SAIC model overpredicts beyond an order of magnitude for a few UF{sub 6}-specific data points. The RTM-96 model provides overpredictions within a factor of 3 for all data points beyond 400 m from the source. For one data set, however, the RTM-96 model severely underpredicts the observations within 200 m of the source. Outputs of the models are most sensitive to the meteorological parameters at large distances from the source and to certain source-specific and meteorological parameters at distances close to the source. Specific recommendations are being made to improve the applicability and usefulness of the three models and to choose a specific model to support the intended analyses. Guidance is also provided on the choice of input parameters for initial dilution, building wake effects, and distance to completion of UF{sub 6} reaction with water.

Assessment of UF6 Equation of State

Energy Technology Data Exchange (ETDEWEB)

Brady, P; Chand, K; Warren, D; Vandersall, J

2009-02-11

A common assumption in the mathematical analysis of flows of compressible fluids is to treat the fluid as a perfect gas. This is an approximation, as no real fluid obeys the perfect gas relationships over all temperature and pressure conditions. An assessment of the validity of treating the UF{sub 6} gas flow field within a gas centrifuge with perfect gas relationships has been conducted. The definition of a perfect gas is commonly stated in two parts: (1) the gas obeys the thermal equation of state, p = {rho}RT (thermally perfect), and, (2) the gas specific heats are constant (calorically perfect). Analysis indicates the thermally perfect assumption is valid for all flow conditions within the gas centrifuge, including shock fields. The low operating gas pressure is the primary factor in the suitability of the thermally perfect equation of state for gas centrifuge computations. UF{sub 6} is not calorically perfect, as the specific heats vary as a function of temperature. This effect is insignificant within the bulk of the centrifuge gas field, as gas temperatures vary over a narrow range. The exception is in the vicinity of shock fields, where temperature, pressure, and density gradients are large, and the variation of specific heats with temperature should be included in the technically detailed analyses. Results from a normal shock analysis incorporating variable specific heats is included herein, presented in the conventional form of shock parameters as a function of inlet Mach Number. The error introduced by assuming constant specific heats is small for a nominal UF{sub 6} shock field, such that calorically perfect shock relationships can be used for scaling and initial analyses. The more rigorous imperfect gas analysis should be used for detailed analyses.

Scoping study to expedite development of a field deployable and portable instrument for UF6 enrichment assay

Energy Technology Data Exchange (ETDEWEB)

Chan, George; Valentine, John D.; Russo, Richard E.

2017-09-14

The primary objective of the present study is to identity the most promising, viable technologies that are likely to culminate in an expedited development of the next-generation, field-deployable instrument for providing rapid, accurate, and precise enrichment assay of uranium hexafluoride (UF6). UF6 is typically involved, and is arguably the most important uranium compound, in uranium enrichment processes. As the first line of defense against proliferation, accurate analytical techniques to determine the uranium isotopic distribution in UF6 are critical for materials verification, accounting, and safeguards at enrichment plants. As nuclear fuel cycle technology becomes more prevalent around the world, international nuclear safeguards and interest in UF6 enrichment assay has been growing. At present, laboratory-based mass spectrometry (MS), which offers the highest attainable analytical accuracy and precision, is the technique of choice for the analysis of stable and long-lived isotopes. Currently, the International Atomic Energy Agency (IAEA) monitors the production of enriched UF6 at declared facilities by collecting a small amount (between 1 to 10 g) of gaseous UF6 into a sample bottle, which is then shipped under chain of custody to a central laboratory (IAEA’s Nuclear Materials Analysis Laboratory) for high-precision isotopic assay by MS. The logistics are cumbersome and new shipping regulations are making it more difficult to transport UF6. Furthermore, the analysis is costly, and results are not available for some time after sample collection. Hence, the IAEA is challenged to develop effective safeguards approaches at enrichment plants. In-field isotopic analysis of UF6 has the potential to substantially reduce the time, logistics and expense of sample handling. However, current laboratory-based MS techniques require too much infrastructure and operator expertise for field deployment and operation. As outlined in the IAEA Department of Safeguards Long

Antecedents of Psychological Contract Breach: The Role of Job Demands, Job Resources, and Affect.

Directory of Open Access Journals (Sweden)

Tim Vantilborgh

Full Text Available While it has been shown that psychological contract breach leads to detrimental outcomes, relatively little is known about factors leading to perceptions of breach. We examine if job demands and resources predict breach perceptions. We argue that perceiving high demands elicits negative affect, while perceiving high resources stimulates positive affect. Positive and negative affect, in turn, influence the likelihood that psychological contract breaches are perceived. We conducted two experience sampling studies to test our hypotheses: the first using daily surveys in a sample of volunteers, the second using weekly surveys in samples of volunteers and paid employees. Our results confirm that job demands and resources are associated with negative and positive affect respectively. Mediation analyses revealed that people who experienced high job resources were less likely to report psychological contract breach, because they experienced high levels of positive affect. The mediating role of negative affect was more complex, as it increased the likelihood to perceive psychological contract breach, but only in the short-term.

Antecedents of Psychological Contract Breach: The Role of Job Demands, Job Resources, and Affect.

Science.gov (United States)

Vantilborgh, Tim; Bidee, Jemima; Pepermans, Roland; Griep, Yannick; Hofmans, Joeri

2016-01-01

While it has been shown that psychological contract breach leads to detrimental outcomes, relatively little is known about factors leading to perceptions of breach. We examine if job demands and resources predict breach perceptions. We argue that perceiving high demands elicits negative affect, while perceiving high resources stimulates positive affect. Positive and negative affect, in turn, influence the likelihood that psychological contract breaches are perceived. We conducted two experience sampling studies to test our hypotheses: the first using daily surveys in a sample of volunteers, the second using weekly surveys in samples of volunteers and paid employees. Our results confirm that job demands and resources are associated with negative and positive affect respectively. Mediation analyses revealed that people who experienced high job resources were less likely to report psychological contract breach, because they experienced high levels of positive affect. The mediating role of negative affect was more complex, as it increased the likelihood to perceive psychological contract breach, but only in the short-term.

Depleted UF6 Internet Resources

Science.gov (United States)

government agencies, international organizations, trade associations, private entities and information ) Honeywell General Atomics International Organizations International Atomic Energy Agency (IAEA) Nuclear , Recommendation 95-1 Administrative Governmental Organizations Department of Defense Department of Transportation

An Examination of the Explicit Costs of Sensitive Information Security Breaches

Science.gov (United States)

Toe, Cleophas Adeodat

2013-01-01

Data security breaches are categorized as loss of information that is entrusted in an organization by its customers, partners, shareholders, and stakeholders. Data breaches are significant risk factors for companies that store, process, and transmit sensitive personal information. Sensitive information is defined as confidential or proprietary…

Whole-body voxel phantoms of paediatric patients—UF Series B

Science.gov (United States)

Lee, Choonik; Lee, Choonsik; Williams, Jonathan L.; Bolch, Wesley E.

2006-09-01

Following the previous development of the head and torso voxel phantoms of paediatric patients for use in medical radiation protection (UF Series A), a set of whole-body voxel phantoms of paediatric patients (9-month male, 4-year female, 8-year female, 11-year male and 14-year male) has been developed through the attachment of arms and legs from segmented CT images of a healthy Korean adult (UF Series B). Even though partial-body phantoms (head-torso) may be used in a variety of medical dose reconstruction studies where the extremities are out-of-field or receive only very low levels of scatter radiation, whole-body phantoms play important roles in general radiation protection and in nuclear medicine dosimetry. Inclusion of the arms and legs is critical for dosimetry studies of paediatric patients due to the presence of active bone marrow within the extremities of children. While the UF Series A phantoms preserved the body dimensions and organ masses as seen in the original patients who were scanned, comprehensive adjustments were made for the Series B phantoms to better match International Commission on Radiological Protection (ICRP) age-interpolated reference body masses, body heights, sitting heights and internal organ masses. The CT images of arms and legs of a Korean adult were digitally rescaled and attached to each phantom of the UF series. After completion, the resolutions of the phantoms for the 9-month, 4-year, 8-year, 11-year and 14-year were set at 0.86 mm × 0.86 mm × 3.0 mm, 0.90 mm × 0.90 mm × 5.0 mm, 1.16 mm × 1.16 mm × 6.0 mm, 0.94 mm × 0.94 mm × 6.00 mm and 1.18 mm × 1.18 mm × 6.72 mm, respectively.

Application of fixed bed trapping technology for the removal of low concentration UF6 from plant gaseous effluent streams

International Nuclear Information System (INIS)

Russell, R.G.

1987-01-01

For the trapping of UF 6 in nitrogen, NaF > Al 2 O 3 > CaSO 4 . UF 6 inlet concentration has little effect on loading of alumina. Velocity shows an effect on UF 6 loading on alumina, with higher loading at low velocity. There is no significant difference in UF 6 loading between alumina 201A and 202HF. UF 6 outlet concentrations prior to breakthrough were measured to be as low as 2 O 3 until breakthrough (6.6% vs 5.3%), after which NaF experiences more loading (7.5% vs 11.5% at 1 ppM in the outlet). Higher trap loadings at lower pressures for both NaF and Al 2 O 3 . Al 2 O 3 was more efficient than NaF at higher velocities

Thermal reactions of uranium metal, UO 2, U 3O 8, UF 4, and UO 2F 2 with NF 3 to produce UF 6

Science.gov (United States)

McNamara, Bruce; Scheele, Randall; Kozelisky, Anne; Edwards, Matthew

2009-11-01

This paper demonstrates that NF 3 fluorinates uranium metal, UO 2, UF 4, UO 3, U 3O 8, and UO 2F 2·2H 2O to produce the volatile UF 6 at temperatures between 100 and 550 °C. Thermogravimetric and differential thermal analysis reaction profiles are described that reflect changes in the uranium fluorination/oxidation state, physiochemical effects, and instances of discrete chemical speciation. Large differences in the onset temperatures for each system investigated implicate changes in mode of the NF 3 gas-solid surface interaction. These studies also demonstrate that NF 3 is a potential replacement fluorinating agent in the existing nuclear fuel cycle and in actinide volatility reprocessing.

UF{sub 6} cylinder lifting equipment enhancements

Energy Technology Data Exchange (ETDEWEB)

Hortel, J.M. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

1991-12-31

This paper presents numerous enhancements that have been made to the Portsmouth lifting equipment to ensure the safe handling of cylinders containing liquid uranium hexafluoride (UF{sub 6}). The basic approach has been to provide redundancy to all components of the lift path so that any one component failure would not cause the load to drop or cause any undesirable movement.

Method for selectively removing fluorine and fluorine-containing contaminants from gaseous UF/sub 6/. [ClF/sub 3/

Science.gov (United States)

Jones, R.L.; Otey, M.G.; Perkins, R.W.

1980-11-24

This invention is a method for effecting preferential removal and immobilization of certain gaseous contaminants from gaseous UF/sub 6/. The contaminants include fluorine and fluorides which are more reactive with CaCO/sub 3/ than is UF/sub 6/. The method comprises contacting the contaminant-carrying UF/sub 6/ with particulate CaCO/sub 3/ at a temperature effecting reaction of the contaminant and the CaCO/sub 3/.

78 FR 5565 - Modifications to the HIPAA Privacy, Security, Enforcement, and Breach Notification Rules Under...

Science.gov (United States)

2013-01-25

... RIN 0945-AA03 Modifications to the HIPAA Privacy, Security, Enforcement, and Breach Notification Rules... HIPAA Privacy, Security, Breach Notification, and Enforcement Rules (the HIPAA Rules) to improve their... entities Total cost Notices of Privacy Practices.. 700,000 covered $55.9 million. entities. Breach...

I Am So Tired… How Fatigue May Exacerbate Stress Reactions to Psychological Contract Breach.

Science.gov (United States)

Achnak, Safâa; Griep, Yannick; Vantilborgh, Tim

2018-01-01

Previous research showed that perceptions of psychological contract (PC) breach have undesirable individual and organizational consequences. Surprisingly, the PC literature has paid little to no attention to the relationship between PC breach perceptions and stress. A better understanding of how PC breach may elicit stress seems crucial, given that stress plays a key role in employees' physical and mental well-being. Based on Conservation of Resources Theory, we suggest that PC breach perceptions represent a perceived loss of valued resources, subsequently leading employees to experience higher stress levels resulting from emerging negative emotions. Moreover, we suggest that this mediated relationship is moderated by initial levels of fatigue, due to fatigue lowering the personal resources necessary to cope with breach events. To tests our hypotheses, we analyzed the multilevel data we obtained from two experience sampling designs (Study 1: 51 Belgian employees; Study 2: 53 US employees). Note that the unit of analysis is "observations" rather than "respondents," resulting in an effective sample size of 730 (Study 1) and 374 (Study 2) observations. In both studies, we found evidence for the mediating role of negative emotions in the PC breach-stress relationship. In the second study, we also found evidence for the moderating role of fatigue in the mediated PC breach-stress relationship. Implications for research and practice are discussed.

An inverse method to estimate the flow through a levee breach

Science.gov (United States)

D'Oria, Marco; Mignosa, Paolo; Tanda, Maria Giovanna

2015-08-01

We propose a procedure to estimate the flow through a levee breach based on water levels recorded in river stations downstream and/or upstream of the failure site. The inverse problem is solved using a Bayesian approach and requires the execution of several forward unsteady flow simulations. For this purpose, we have used the well-known 1-D HEC-RAS model, but any unsteady flow model could be adopted in the same way. The procedure has been tested using four synthetic examples. Levee breaches with different characteristics (free flow, flow with tailwater effects, etc.) have been simulated to collect the synthetic level data used at a later stage in the inverse procedure. The method was able to accurately reproduce the flow through the breach in all cases. The practicability of the procedure was then confirmed applying it to the inundation of the Polesine Region (Northern Italy) which occurred in 1951 and was caused by three contiguous and almost simultaneous breaches on the left embankment of the Po River.

[Experimental evaluation of the Sysmex UF-1000i for ruling out non-gonococcal urethritis].

Science.gov (United States)

Grosso, Shamanta; Bruschetta, Graziano; Camporese, Alessandro

2012-09-01

Acute nongonococcal urethritis (NGU) is one of the commonest sexually transmitted infections affecting men and women. The diagnosis of NGU has traditionally required microscopic evidence of urethritis. However, a significant proportion of patients with urethral symptoms do not have microscopic evidence of urethritis. The purpose of the present study was to evaluate the analytical performance of the UF1000i, a recently introduced fluorescence flow cytometer intended for urinalysis purposes which provides new analytical features that seem particularly suitable for microbiological diagnostics, for ruling out NGU or predicting the presence of infection. The Sysmex UF1000i is a flow cytometry analyzer capable of quantifying a lot of particles, including bacteria (BACT) and white blood cells (WBCs). To evaluate the analytical performance of the UF1000i as a method for ruling out NGU, we examined 200 urethral smear samples, collected in a new liquid transport medium (Copan), and compared the UF1000i results with standard culture/molecular and microscopic Gram stain results. With instrument cut-off values of 200 BACT x 10^6/L and 500 WBCs x 10^6/L, we obtained a sensitivity of 84%, a specificity of 82%, and a high negative predictive value (96%). Culture/molecular detection of pathogens remains the gold standard technique for the diagnosis of NGU. However, the Sysmex UF1000i is capable of improving the efficiency of NGU presumptive diagnosis, providing results in a few minutes, with a high negative predictive value and high values of sensitivity.

Current status of the Run-Beyond-Cladding Breach (RBCB) tests for the Integral Fast Reactor (IFR)

International Nuclear Information System (INIS)

Batte, G.L.; Pahl, R.G.; Hofman, G.L.

1993-01-01

This paper describes the results from the Integral Fast Reactor (IFR) metallic fuel Run-Beyond-Cladding-Breach (RBCB) experiments conducted in the Experimental Breeder Reactor II (EBR-II). Included in the report are scoping test results and the data collected from the prototypical tests as well as the exam results and discussion from a naturally occurring breach of one of the lead IFR fuel tests. All results showed a characteristic delayed neutron and fission gas release pattern that readily allows for identification and evaluation of cladding breach events. Also, cladding breaches are very small and do not propagate during extensive post breach operation. Loss of fuel from breached cladding was found to be insignificant. The paper will conclude with a brief description of future RBCB experiments planned for irradiation in EBR-II

The toxic and radiological risk equivalence approach in UF6 transport

International Nuclear Information System (INIS)

Ringot, C.; Hamard, J.

1988-12-01

After a brief description of the safety in transport of UF 6 , we discuss the equivalence of the radioactive and chemical risks in UF 6 transport regulations. As the concept of low specific activity appears to be ill-suited for a toxic gas, we propose a quantity of material limit designated T 2 (equivalent to A 2 for radioactive substances) for packagings unable to withstand accident conditions (9 m drop, 800 0 C fire environment for 30 minutes). It is proposed that this limit be chosen for the amount of release acceptable after AIEA tests. Different possible scenarios are described, with fire assumed to be the most severe toxic risk situation

Evaluating the effects of dam breach methodologies on Consequence Estimation through Sensitivity Analysis

Science.gov (United States)

Kalyanapu, A. J.; Thames, B. A.

2013-12-01

Dam breach modeling often includes application of models that are sophisticated, yet computationally intensive to compute flood propagation at high temporal and spatial resolutions. This results in a significant need for computational capacity that requires development of newer flood models using multi-processor and graphics processing techniques. Recently, a comprehensive benchmark exercise titled the 12th Benchmark Workshop on Numerical Analysis of Dams, is organized by the International Commission on Large Dams (ICOLD) to evaluate the performance of these various tools used for dam break risk assessment. The ICOLD workshop is focused on estimating the consequences of failure of a hypothetical dam near a hypothetical populated area with complex demographics, and economic activity. The current study uses this hypothetical case study and focuses on evaluating the effects of dam breach methodologies on consequence estimation and analysis. The current study uses ICOLD hypothetical data including the topography, dam geometric and construction information, land use/land cover data along with socio-economic and demographic data. The objective of this study is to evaluate impacts of using four different dam breach methods on the consequence estimates used in the risk assessments. The four methodologies used are: i) Froehlich (1995), ii) MacDonald and Langridge-Monopolis 1984 (MLM), iii) Von Thun and Gillete 1990 (VTG), and iv) Froehlich (2008). To achieve this objective, three different modeling components were used. First, using the HEC-RAS v.4.1, dam breach discharge hydrographs are developed. These hydrographs are then provided as flow inputs into a two dimensional flood model named Flood2D-GPU, which leverages the computer's graphics card for much improved computational capabilities of the model input. Lastly, outputs from Flood2D-GPU, including inundated areas, depth grids, velocity grids, and flood wave arrival time grids, are input into HEC-FIA, which provides the

Dynamic coating of mf/uf membranes for fouling mitigation

KAUST Repository

Tabatabai, S. Assiyeh Alizadeh; Leiknes, TorOve

2017-01-01

A membrane system including an anti-fouling layer and a method of applying an anti-fouling layer to a membrane surface are provided. In an embodiment, the surface is a microfiltration (MF) or an ultrafiltration (UF) membrane surface. The anti

Breached-pin testing in the US

International Nuclear Information System (INIS)

Mahagin, D.E.; Lambert, J.D.B.

1981-04-01

Experience gained at EBR-II by the late 1970's from a significant number of failures in experimental fuel-pin irradiations forms the basis of a program directed towards the characterization of breached pins. The questions to be answered and the issues raised by further testing are discussed

Conversion of U3O8 to UF6

International Nuclear Information System (INIS)

Bodu, R.L.

1975-01-01

Three main processes for the production of UF 6 from the uranium ores (yellow cake) is described. The economic aspects of the conversion - capital cost, operating costs and conversion market and the future of conversion - capacity and prices - are discussed. (HPH) [de

Overview of toxicity data and risk assessment methods for evaluating the chemical effects of depleted uranium compounds

International Nuclear Information System (INIS)

Hartmann, H.M.; Monette, F.A.; Avci, H.I.

2000-01-01

In the United States, depleted uranium is handled or used in several chemical forms by both governmental agencies and private industry (primarily companies producing and machining depleted uranium metal for military applications). Human exposure can occur as a result of handling these compounds, routine low-level effluent releases to the environment from processing facilities, or materials being accidentally released from storage locations or during processing or transportation. Exposure to uranium can result in both chemical and radiological toxicity, but in most instances chemical toxicity is of greater concern. This article discusses the chemical toxic effects from human exposure to depleted uranium compounds that are likely to be handled during the long-term management and use of depleted uranium hexafluoride (UF 6 ) inventories in the United States. It also reviews representative publications in the toxicological literature to establish appropriate reference values for risk assessments. Methods are described for evaluating chemical toxicity caused by chronic low-level exposure and acute exposure. Example risk evaluations are provided for illustration. Preliminary results indicate that chemical effects of chronic exposure to uranium compounds under normal operating conditions would be negligibly small. Results also show that acute exposures under certain accident conditions could cause adverse chemical effects among the populations exposed.

Testing the Differential Effects of Changes in Psychological Contract Breach and Fulfillment

Science.gov (United States)

Conway, Neil; Guest, David; Trenberth, Linda

2011-01-01

Rousseau (1989 and elsewhere) argued that a defining feature of psychological contract breach was that once a promise had been broken it could not easily be repaired and therefore that the effects of psychological contract breach outweighed those of psychological contract fulfillment. Using two independent longitudinal surveys, this paper…

Alternative method of retesting UF{sub 6} cylinders

Energy Technology Data Exchange (ETDEWEB)

Christ, R. [Nuclear Crago + Service GmbH, Hanau (Germany)

1991-12-31

The paper describes an alternative method to perform the periodic inspection of UF{sub 6} cylinders. The hydraulic test is replaced by ultrasonic checking of wall thickness and by magnetic particle testing of all the weld seams. Information about the legal background, the air leak test and the qualification of inspectors is also given.

Reimiep 87. An interlaboratory U-235 enrichment determination by gamma measurement on solid UF6 sample

International Nuclear Information System (INIS)

Aparo, M.; Cresti, P.

1988-01-01

Gamma spectroscopy technique, based on the measurement of U 235 186 KeV flux, is now currently used for the determination of Uranium enrichment in different material of nuclear fuel cycle, namely: Uranium metallic, UO 2 pellets, UF 6 liquid or solid. The present paper describes the use of such a technique and the obtained results in determining the U 235 /U atomic isotopic abundance on a certified UF 6 solid sample. The measurements have been carried out in the frame work of the partecipation to the ''UF 6 Interlaboratory Measurements Evaluation Programme'' organized by CBNM/Geel with the support of the ESARDA (European Safeguards Research and Development Association)

Treatment of car wash wastewater by UF membranes

Science.gov (United States)

Istirokhatun, Titik; Destianti, Puti; Hargianintya, Adenira; Oktiawan, Wiharyanto; Susanto, Heru

2015-12-01

The existence of car wash service facilitates car owners to remove dirt and grime from their vehicles. However, the dirt washed off vehicles as well as the cleaning materials themselves may be harmful to the environment if they are not properly managed and discharged. Many technologies have been proposed to treat car wash wastewater such as coagulation flocculation, tricking filter and flocculation-flotation. Nevertheless, these technologies have low efficiency to eliminate oil and small organic compounds. Ultrafiltration (UF) membranes were used in this study to treat car wash wastewater. This study investigated the performance of UF membranes under various pressures to remove COD, oil and grease, and also turbidity from car wash waste water. The membrane performance was examined by investigation of permeate flux and membrane rejection. The results meet the standard of environmental regulation and it is possible to be reused. The highest rejection was shown by PES10 (polyethersulfone 10 kDa) in 1 bar operation with complete rejection for both turbidity and oil and grace and 95% rejection for COD.

Metals, heavy metals and microorganism removal from spent filter backwash water by hybrid coagulation-UF processes

Directory of Open Access Journals (Sweden)

Mokhtar Mahdavi

2018-04-01

Full Text Available Spent filter backwash water (SFBW reuse has attracted particular attention, especially in countries that experience water scarcity. It can act as a permanent water source until the water treatment plant is working. In this study, the concentrations of Fe, Al, Pb, As, and Cd with total and fecal coliform (TC/FC were investigated in raw and treated SFBW by hybrid coagulation-UF processes. The pilot plant consisted of pre-sedimentation, coagulation, flocculation, clarification, and ultrafiltration (UF units. Poly-aluminum ferric chloride (PAFCL and ferric chloride (FeCl3 were used as pretreatment. The results showed that, at the optimum dose of PAFCl, the average removal of TC and FC was 88 and 79% and with PAFCl-UF process, it reached 100 and 100%, respectively. For FeCl3, removal efficiency of TC and FC were 81 and 72% and by applying FeCl3-UF process, it reached 100 and 100%, respectively. In comparison with FeCl3, PAFCl showed better removal efficiency for Fe, Pb, As, and Cd, except residual Al concentration. Coagulation-UF process could treat SFBW efficiently and treated SFBW could meet the US-EPA drinking water standard. Health risk index values of Fe, AL, Pb, AS, and Cd in treated SFBW indicate no risk of exposure to the use of this water.

Probing the electronic structures of low oxidation-state uranium fluoride molecules UF{sub x}{sup −} (x = 2−4)

Energy Technology Data Exchange (ETDEWEB)

Li, Wei-Li; Jian, Tian; Lopez, Gary V.; Wang, Lai-Sheng, E-mail: lai-sheng-wang@brown.edu [Department of Chemistry, Brown University, Providence, Rhode Island 02912 (United States); Hu, Han-Shi; Li, Jun, E-mail: junli@tsinghua.edu.cn [Department of Chemistry and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084 (China); William R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Su, Jing [Department of Chemistry and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084 (China)

2013-12-28

We report the experimental observation of gaseous UF{sub x}{sup −} (x = 2−4) anions, which are investigated using photoelectron spectroscopy and relativistic quantum chemistry. Vibrationally resolved photoelectron spectra are obtained for all three species and the electron affinities of UF{sub x} (x = 2−4) are measured to be 1.16(3), 1.09(3), and 1.58(3) eV, respectively. Significant multi-electron transitions are observed in the photoelectron spectra of U(5f{sup 3}7s{sup 2})F{sub 2}{sup −}, as a result of strong electron correlation effects of the two 7s electrons. The U−F symmetric stretching vibrational modes are resolved for the ground states of all UF{sub x} (x = 2−4) neutrals. Theoretical calculations are performed to qualitatively understand the photoelectron spectra. The entire UF{sub x}{sup −} and UF{sub x} (x = 1−6) series are considered theoretically to examine the trends of U−F bonding and the electron affinities as a function of fluorine coordination. The increased U−F bond lengths and decreased bond orders from UF{sub 2}{sup −} to UF{sub 4}{sup −} indicate that the U−F bonding becomes weaker as the oxidation state of U increases from I to III.

''Spinolaminar breach'': an important sign in cervical spinous process fractures

International Nuclear Information System (INIS)

Matar, L.D.; Helms, C.A.

2000-01-01

Objective. To report the sign of ''spinolaminar breach'' and its likely importance in fractures of the cervical spinous processes.Design. Six cases of spinous process fractures demonstrating disruption of the spinolaminar line or ''spinolaminar breach'' were analyzed. Lateral and anteroposterior radiographs (n=6), CT scans (n=3) and MRI scans (n=1) were reviewed together by the authors, with consensus being reached as to the radiographic findings. Clinical records were also reviewed.Results. The levels of injury were C6 (n=5) and C5 (n=2). Injuries were associated with delayed anterior subluxation (n=4) and neurological deficit (n=2). Five patients were male and one was female with a mean age of 31 years (range 8-59 years). Injuries resulted from motor vehicle accidents (n=4), a motor cycle accident (n=1) and a fall (n=1).Conclusion. ''Spinolaminar breach'', or disruption of the spinolaminar line, indicates a complex spinous process fracture with extension into the lamina and spinal canal. Spinous process fractures with spinolaminar breach may have associated posterior ligamentous injury with potential for delayed instability and neurological deficit. It is important that radiologists and physicians caring for the trauma patient be aware of this sign in order to avoid misdiagnosis as a ''clay shoveler's fracture'', which can lead to adverse outcome. (orig.)

On Line Enrichment Monitor (OLEM) UF₆ Tests for 1.5" Sch40 SS Pipe, Revision 1

Energy Technology Data Exchange (ETDEWEB)

March-Leuba, José A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Garner, Jim [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Younkin, Jim [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Simmons, Darrell W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-01-01

As global uranium enrichment capacity under international safeguards expands, the International Atomic Energy Agency (IAEA) is challenged to develop effective safeguards approaches at gaseous centrifuge enrichment plants while working within budgetary constraints. The “Model Safeguards Approach for Gas Centrifuge Enrichment Plants” (GCEPs) developed by the IAEA Division of Concepts and Planning in June 2006, defines the three primary Safeguards objectives to be the timely detection of: 1) diversion of significant quantities of natural (NU), depleted (DU) or low-enriched uranium (LEU) from declared plant flow, 2) facility misuse to produce undeclared LEU product from undeclared feed, and 3) facility misuse to produce enrichments higher than the declared maximum, in particular, highly enriched uranium (HEU). The ability to continuously and independently (i.e. with a minimum of information from the facility operator) monitor not only the uranium mass balance but also the ²³⁵U mass balance in the facility could help support all three verification objectives described above. Two key capabilities required to achieve an independent and accurate material balance are 1) continuous, unattended monitoring of in-process UF₆ and 2) monitoring of cylinders entering and leaving the facility. The continuous monitoring of in-process UF₆ would rely on a combination of load-cell monitoring of the cylinders at the feed and withdrawal stations, online monitoring of gas enrichment, and a high-accuracy net weight measurement of the cylinder contents. The Online Enrichment Monitor (OLEM) is the instrument that would continuously measure the time-dependent relative uranium enrichment, E(t), in weight percent ²³⁵U, of the gas filling or being withdrawn from the cylinders. The OLEM design concept combines gamma-ray spectrometry using a collimated NaI(Tl) detector with gas pressure and temperature data to calculate the enrichment of the UF₆

Temporary patching of damaged UF{sub 6} cylinders

Energy Technology Data Exchange (ETDEWEB)

Cardenas, A.L. [Martin Marietta Energy Systems, Inc., OH (United States)

1991-12-31

Patching techniques based on application of epoxy resins have been developed for temporarily repairing UF{sub 6} cylinders which have sustained relatively minor damage and must be safely emptied. The method is considerably faster and simpler than metallurgical weld repairs. Laboratory tests, detailed operational procedures, and case histories of experience at the Portsmouth Gaseous Diffusion Plant are described.

Information Society Services and Mandatory Data Breach Notifications: Introduction to Open Issues in the EU Framework

OpenAIRE

Burnik, Jelena

2012-01-01

In 2011 Sony suffered an extensive breach in its online game network that led to the theft of account data of 77 million users from all over the world. This was one of the largest internet security break-ins that resulted in a large scale personal data breach. As an answer to numerous incidents of security breaches where personal data have been compromised, an instrument of mandatory data breach notification is currently being implemented in the European Union that follows the approach taken ...

On the importance of default breach remedies

NARCIS (Netherlands)

Sloof, R.; Oosterbeek, H.; Sonnemans, J.

2007-01-01

Theory predicts that default breach remedies are immaterial whenever contracting costs are negligible. Some experimental studies, however, suggest that in practice default rules do matter, as they may affect parties' preferences over contract terms. This paper presents results from an experiment

Electrically Cooled Germanium System for Measurements of Uranium Enrichments in UF6 Cylinders

International Nuclear Information System (INIS)

Dvornyak, P.; Koestlbauer, M.; Lebrun, A.; Murray, M.; Nizhnik, V.; Saidler, C.; Twomey, T.

2010-01-01

Measurements of Uranium enrichment in UF6 cylinders is a significant part of the IAEA Safeguards verification activities at enrichment and conversion plants. Nowadays, one of the main tools for verification of Uranium enrichment in UF6 cylinders used by Safeguards inspectors is the gamma spectroscopy system with HPGe detector cooled with liquid nitrogen. Electrically Cooled Germanium System (ECGS) is a new compact and portable high resolution gamma spectrometric system free from liquid nitrogen cooling, which can be used for the same safeguards applications. It consists of the ORTEC Micro-trans-SPEC HPGe Portable Spectrometer, a special tungsten collimator and UF6 enrichment measurement software. The enrichment of uranium is determined by of quantifying the area of the 185.7 keV peak provided that the measurement is performed with a detector viewing an infinite thickness of material. Prior starting the verification of uranium enrichment at the facility, the ECGS has to be calibrated with a sample of known uranium enrichment, material matrix, container wall thickness and container material. Evaluation of the ECGS capabilities was performed by carrying out a field test on actual enrichment verification of uranium in UF6 cylinder or other forms of uranium under infinite thickness conditions. The results of these evaluations allow to say that the use of ECGS will enhance practicality of the enrichment measurements and support unannounced inspection activities at enrichment and conversion plants. (author)

Toward a better understanding of psychological contract breach: a study of customer service employees.

Science.gov (United States)

Deery, Stephen J; Iverson, Roderick D; Walsh, Janet T

2006-01-01

Experiences of psychological contract breach have been associated with a range of negative behavior. However, much of the research has focused on master of business administration alumni and managers and made use of self-reported outcomes. Studying a sample of customer service employees, the research found that psychological contract breach was related to lower organizational trust, which, in turn was associated with perceptions of less cooperative employment relations and higher levels of absenteeism. Furthermore, perceptions of external market pressures moderated the effect of psychological contract breach on absenteeism. The study indicated that psychological contract breach can arise when employees perceive discrepancies between an organization's espoused behavioral standards and its actual behavioral standards, and this can affect discretionary absence. (c) 2006 APA, all rights reserved.

Morphologic evolution of the wilderness area breach at Fire Island, New York—2012–15

Science.gov (United States)

Hapke, Cheryl J.; Nelson, Timothy R.; Henderson, Rachel E.; Brenner, Owen T.; Miselis, Jennifer L.

2017-09-18

IntroductionHurricane Sandy, which made landfall on October 29, 2012, near Atlantic City, New Jersey, had a significant impact on the coastal system along the south shore of Long Island, New York. A record significant wave height of 9.6 meters (m) was measured at wave buoy 44025, approximately 48 kilometers offshore of Fire Island, New York. Surge and runup during the storm resulted in extensive beach and dune erosion and breaching of the Fire Island barrier island system at two locations, including a breach that formed within the Otis Pike Fire Island High Dune Wilderness area on the eastern side of Fire Island.The U.S. Geological Survey (USGS) has a long history of conducting morphologic change and processes research at Fire Island. One of the primary objectives of the current research effort is to understand the morphologic evolution of the barrier system on a variety of time scales (from storm scale to decade(s) to century). A number of studies that support the project objectives have been published. Prior to Hurricane Sandy, however, little information was available on specific storm-driven change in this region. The USGS received Hurricane Sandy supplemental funding (project GS2–2B: Linking Coastal Processes and Vulnerability, Fire Island, New York, Regional Study) to enhance existing research efforts at Fire Island. The existing research was greatly expanded to include inner continental shelf mapping and investigations of processes of inner shelf sediment transport; beach and dune response and recovery; and observation, analysis, and modeling of the newly formed breach in the Otis Pike High Dune Wilderness area, herein referred to as the wilderness breach. The breach formed at the site of Old Inlet, which was open from 1763 to 1825. The location of the initial island breaching does not directly correspond with topographic lows of the dunes, but instead the breach formed in the location of a cross-island boardwalk that was destroyed during Hurricane Sandy

A Longitudinal Study of Age-Related Differences in Reactions to Psychological Contract Breach

NARCIS (Netherlands)

Bal, P.M.; Lange, A.H. de; Jansen, P.G.W.; Velde, M.E.G. van der

2013-01-01

The current paper investigated age-related differences in the relations of psychological contract breach with work outcomes over time. Based on affective events theory, we expected job satisfaction to mediate the longitudinal relationship of contract breach with changes in job performance. Moreover,

A longitudinal study of age-related differences in reactions to psychological contract breach

NARCIS (Netherlands)

Bal, P.M.; de Lange, A.H.; Jansen, P.G.W.; van der Velde, E.G.

2013-01-01

The current paper investigated age-related differences in the relations of psychological contract breach with work outcomes over time. Based on affective events theory, we expected job satisfaction to mediate the longitudinal relationship of contract breach with changes in job performance. Moreover,

a longitudinal study of age-related differences in reactions to phsycological contract breach

NARCIS (Netherlands)

Paul Jansen; Annet de Lange; Matthijs Bal; Mandy van der Velde

2013-01-01

The current paper investigated age‐related differences in the relations of psychological contract breach with work outcomes over time. Based on affective events theory, we expected job satisfaction to mediate the longitudinal relationship of contract breach with changes in job performance. Moreover,

Pro-active data breach detection: examining accuracy and applicability on personal information detected

CSIR Research Space (South Africa)

Botha, J

2016-03-01

Full Text Available breaches but does not provide a clear indication of the level of personal information available on the internet since only reported incidents are taken into account. The possibility of pro-active automated breach detection has previously been discussed as a...

Presentation and interpretation of field experiments of gaseous UF6 releases in the atmosphere

International Nuclear Information System (INIS)

Crabol, B.; Boulaud, D.; Deville-Cavelin, G.

1992-01-01

An experimental programme concerning the behaviour of UF 6 released in gaseous phase in the atmosphere has been conducted in the years 1986-1989 by the french Atomic Energy Commission and Eurodif. Three field tests have been performed on the CEA/CESTA experimental site. These experiments permitted to get informations about the kinetics of the hydrolysis reaction of the UF 6 , the behaviour of the hydrolysis products in the atmosphere and the granulometry of the solid particles

Presentation and interpretation of field experiments of gaseous UF6 releases in the atmosphere

Energy Technology Data Exchange (ETDEWEB)

Crabol, B.; Boulaud, D.; Deville-Cavelin, G. [CEA Centre d`Etudes de Fontenay-aux-Roses, 92 (France). Dept. de Protection de l`Environnement et des Installations; Geisse, C.; Iacona, L. [EURODIF, 26 - Pierrelatte (France)

1992-12-31

An experimental programme concerning the behaviour of UF{sub 6} released in gaseous phase in the atmosphere has been conducted in the years 1986-1989 by the french Atomic Energy Commission and Eurodif. Three field tests have been performed on the CEA/CESTA experimental site. These experiments permitted to get informations about the kinetics of the hydrolysis reaction of the UF{sub 6}, the behaviour of the hydrolysis products in the atmosphere and the granulometry of the solid particles.

Experimental study of lactose hydrolysis and separation in cstr-uf membrane reactor

Directory of Open Access Journals (Sweden)

M. Namvar-Mahboub

2012-09-01

Full Text Available In this study, the effect of processing conditions on the performance of continuous stirred tank -ultrafiltration (CSTR-UF in dead - end mode was investigated. An UF membrane with a molecular weight cutoff of 3 kDa made of regenerated cellulose material was used to separate enzyme from products. The effect of operating pressure ranging between 2 and 5 bar and time on the performance of the CSTR-UF system was studied. The experiments were performed with a 0.139 molar aqueous solution of lactose as feed. According to the experimental data, the lactose concentration in the permeate decreased with time due to concentration polarization and hydrolysis. It was found that the rejection factor of lactose increases from 33 to 77% with time from 5 to 85 min. Permeation flux of the membrane was evaluated in terms of pure water flux (PWF and lactose aqueous solution. Results showed that a high operating pressure led to a high permeation flux for both mentioned cases. Also, adding lactose and enzyme to pure water caused a reduction of the permeation flux due to concentration polarization.

Long-term evaluation of fluoroelastomer O-rings in UF6

International Nuclear Information System (INIS)

Russell, R.G.; Otey, M.G.; Dippo, G.L.

1986-01-01

A major component in the gaseous centrifuge enrichment plant (GCEP) was fluoroelastomer O-rings, which were used to seal the uranium hexafluoride (UF 6 ) gas system. A program utilizing accelerated test conditions was used to help identify the best material out of four selected candidates and to predict the service life of these materials at GCEP conditions. The tests included accelerated temperatures, mechanical stress, and UF 6 exposure. Data were evaluated using the Newman--Keuls 1 ranking system to identify the best material and a zero-order reaction rate equation to help predict service life. This presentation includes a description of the test facility, the materials tested, the types of tests, objectives of the study, service life predictions, and conclusions. The O-rings are predicted to last approx. 30 years, and a high-molecular-weight polymer had the best performance ranking

Uniform deposition of uranium hexafluoride (UF6): Standardized mass deposits and controlled isotopic ratios using a thermal fluorination method

Energy Technology Data Exchange (ETDEWEB)

McNamara, Bruce K.; O’Hara, Matthew J.; Casella, Andrew M.; Carter, Jennifer C.; Addleman, R. Shane; MacFarlan, Paul J.

2016-07-01

Abstract: We report a convenient method for the generation of volatile uranium hexafluoride (UF6) from solid uranium oxides and other uranium compounds, followed by uniform deposition of low levels of UF6 onto sampling coupons. Under laminar flow conditions, UF6 is shown to interact with surfaces within the chamber to a highly predictable degree. We demonstrate the preparation of uranium deposits that range between ~0.01 and 470±34 ng∙cm-2. The data suggest the method can be extended to creating depositions at the sub-picogram∙cm-2 level. Additionally, the isotopic composition of the deposits can be customized by selection of the uranium source materials. We demonstrate a layering technique whereby two uranium solids, each with a different isotopic composition, are employed to form successive layers of UF6 on a surface. The result is an ultra-thin deposit of UF6 that bears an isotopic signature that is a composite of the two uranium sources. The reported deposition method has direct application to the development of unique analytical standards for nuclear safeguards and forensics.

Computational simulation studies of the reduction process of UF4 to metallic uranium

International Nuclear Information System (INIS)

Borges, Wesden de Almeida

2011-01-01

The production of metallic uranium is essential for production of fuel elements for using in nuclear reactors manufacturing of radioisotopes and radiopharmaceuticals. In IPEN, metallic uranium is produced by magnesiothermical reduction of UF 4 . This reaction is performed in a closed graphite crucible inserted in a sealed metal reactor and no contact with the outside environment. The set is gradually heated in an oven pit, until it reaches the ignition temperature of the reaction (between 600-650 degree C). The modeling of the heating profile of the system can be made using simulation programs by finite element method. Through the thermal profiles in the load, we can have a notion of heating period required for the reaction to occur, allowing the identification of the same group in a greater or smaller yield in metallic uranium production. Thermal properties of UF 4 are estimated, obtaining thermal conductivity and heat capacity using the Flash Laser Method, and for the load UF 4 + Mg, either. The results are compared to laboratory tests to simulate the primary production process. (author)

Avslag på uførepensjon

Directory of Open Access Journals (Sweden)

Anders M. Galaasen

2010-01-01

Full Text Available Introduksjon: Mens mye er skrevet om hvem som får uførepensjon, foreligger det få vitenskapelige artikler om avslag på søknad om uførepensjon.Mål: Vi har gjennomført en undersøkelse over hvem som får avslag på søknad om uførepensjon og hvorledes det går med dem i en 6-7 års oppfølging.Metoder: Data fra FD-trygd, koplet med Statistisk sentralbyrås demografiske data er brukt for å sammenlikne dem som får avslag med dem som blir innvilget uførepensjon 1993 ut fra alder, kjønn, utdanning, etnisitet og inntekt. Trygdestatus for dem med avslag er så fulgt til 2000.Resultater: Vi har funnet at kvinner oftere får avslag enn menn, at de eldste og yngste sjeldnere får avslag og at de med minst inntekt og ikke-vestlig bakgrunn oftere får avslag, mens avslagsprosenten er omtrent den samme på alle utdanningsnivåer. I en oppfølging frem til 2000 viser det seg at de fleste ender opp med trygdeytelser, og at kjønnsforskjellene ytterligere forsterkes. De få av de yngste som får avslag, er relativt hyppig fortsatt uten ytelser.Konklusjon: Selv om noen av dem som får avslag, klarer å komme tilbake til normalt lønnsarbeid, og derigjennom bidra til økt produktivitet, resulterer avslag oftere kun i en utsettelse av overgang til permanente trygdeytelser. Hva den eventuelle samfunnsøkonomiske gevinsten av en slik utsettelse er, når man også tar i betraktning økt saksbehandling fra NAV, samt utgifter til attføring og rehabilitering, er et spørsmål for videre forskning. Galaasen AM, Bruusgaard D, Claussen B. Denial of disability pension. Nor J Epidemiol 2009; 19 (2: 203-208. ENGLISH SUMMARYIntroduction: While much is written about who gets disability pensions, there are few scientific articles on the denial of disability pension.Objective: We conducted a survey of who is rejected disability pension and how their life situation evolves in a 6- 7-year follow-up.Methods: Data from FD-trygd, coupled with Statistics Norway

MF/UF rejection and fouling potential of algal organic matter from bloom-forming marine and freshwater algae

KAUST Repository

Villacorte, Loreen O.

2015-07-01

Pretreatment with microfiltration (MF) or ultrafiltration (UF) membranes has been proposed for seawater reverse osmosis (SWRO) plants to address operational issues associated with algal blooms. Here, we investigated the MF/UF rejection and fouling potential of algal organic matter (AOM) released by common species of bloom-forming marine (Alexandrium tamarense and Chaetoceros affinis) and freshwater (Microcystis sp.) algae. Batch culture monitoring of the three algal species illustrated varying growth pattern, cell concentration, AOM released and membrane fouling potential. The high membrane fouling potential of the cultures can be directly associated (R2>0.85) with AOM such as transparent exopolymer particle (TEP) while no apparent relationship with algal cell concentration was observed. The AOM comprised mainly biopolymers (e.g., polysaccharides and proteins) and low molecular weight organic compounds (e.g., humic-like substances). The former were largely rejected by MF/UF membranes while the latter were poorly rejected. MF (0.4μm and 0.1μm pore size) rejected 14%-56% of biopolymers while conventional UF (100kDa) and tight UF (10kDa) rejected up to 83% and 97%, respectively. The retention of AOM resulted in a rapid increase in trans-membrane pressure (δP) over time, characterised by pore blocking followed by cake filtration with enhanced compression as illustrated by an exponential progression of δP. © 2015 Elsevier B.V.

Battling Data Breaches: For Higher Education Institutions, Data Breach Prevention is More Complex than for Industry and Business

Science.gov (United States)

Patton, Madeline

2015-01-01

Data breach prevention is a battle, rarely plain and never simple. For higher education institutions, the Sisyphean aspects of the task are more complex than for industry and business. Two-year colleges have payrolls and vendor contracts like those enterprises. They also have public record and student confidentiality requirements. Colleges must…

Theoretical study of relativistic effects in the electronic structure and chemical bonding of UF6

International Nuclear Information System (INIS)

Onoe, Jun; Takeuchi, Kazuo; Sekine, Rika; Nakamatsu, Hirohide; Mukoyama, Takeshi; Adachi, Hirohiko.

1992-01-01

We have performed the relativistic molecular orbital calculation for the ground state of UF 6 , using the discrete-variational Dirac-Slater method (DV-DS), in order to elucidate the relativistic effects in the electronic structure and chemical bonding. Compared with the electronic structure calculated by the non-relativistic Hartree-Fock-Slater (DV-X α )MO method, not only the direct relativistic effects (spin-orbit splitting etc), but also the indirect effect due to the change in screening core potential charge are shown to be important in the MO level structure. From the U-F bond overlap population analysis, we found that the U-F bond formation can be explained only by the DV-DS, not by the DV-X α . The calculated electronic structure in valence energy region (-20-OeV) and excitation energies in UV region are in agreement with experiments. (author)

Modelling dune erosion, overwash and breaching at Fire Island (NY) during hurricane Sandy

NARCIS (Netherlands)

De Vet, P.L.M.; McCall, R.T.; Den Bieman, J.P.; Stive, M.J.F.; Van Ormondt, M.

2015-01-01

In 2012, Hurricane Sandy caused a breach at Fire Island (NY, USA), near Pelican Island. This paper aims at modelling dune erosion, overwash and breaching processes that occured during the hurricane event at this stretch of coast with the numerical model XBeach. By using the default settings, the

The effects of artificial sandbar breaching on the macrophyte communities of an intermittently open estuary

Science.gov (United States)

Ribeiro, Jose Pedro N.; Saggio, Ângelo; Lima, Maria Inês Salgueiro

2013-04-01

Artificial sandbar opening of intermittently open estuaries is a practice utilised worldwide to improve water quality, fishing, and recreational amenities and to prevent the flooding of adjacent properties. Breaching causes the water level to drop drastically, exposing plants to two water level extremes. With some exceptions, estuarine communities are adversely affected by this practice. Although breaching can happen naturally, artificial breaching is on the rise, and the impact of manipulating water levels on estuarine communities needs to be investigated. In this work, we described the breaching cycles of the Massaguaçu River Estuary and proposed flooding scenarios for the estuary's macrophyte banks based on our data. We calculated the relationship between plant distribution and flooding conditions and used our calculations to predict the estuary community's composition depending on the water level at breaching time. We discovered a strong relationship between plant distribution and flooding conditions, and we predicted that the estuarine community would be markedly different between flooding scenarios. Low frequency flooding scenarios would be related to submerged macrophytes and, as the flooding frequency increases, macrophytes would be replaced by amphibious plants, and eventually by the arboreal stratus. Therefore, we concluded that an increase in artificial breaching cycles would have a detrimental impact on the estuary community.

MF/UF rejection and fouling potential of algal organic matter from bloom-forming marine and freshwater algae

KAUST Repository

Villacorte, Loreen O.; Ekowati, Yuli; Winters, Harvey; Amy, Gary L.; Schippers, Jan Cornelis; Kennedy, Maria Dolores

2015-01-01

the latter were poorly rejected. MF (0.4μm and 0.1μm pore size) rejected 14%-56% of biopolymers while conventional UF (100kDa) and tight UF (10kDa) rejected up to 83% and 97%, respectively. The retention of AOM resulted in a rapid increase in trans

Argon/UF6 plasma exhaust gas reconstitution experiments using preheated fluorine and on-line diagnostics. [fissioning uranium plasma core reactor design

Science.gov (United States)

Roman, W. C.

1979-01-01

The feasibility of employing a flowing, high-temperature, pure fluorine/UF6 regeneration system to efficiently convert a large fraction of the effluent plasma exhaust back to pure UF6 was demonstrated. The custom built T.O.F. mass spectrometer sampling system permitted on-line measurements of the UF6 concentration at different locations in the exhaust system. Negligible amounts ( 100 ppm) of UF6 were detected in the axial bypass exhaust duct and the exhaust ducts downstream of the cryogenic trap system used to collect the UF6, thus verifying the overall system efficiency over a range of operating conditions. Use of a porous Monel duct as part of the exhaust duct system, including provision for injection of pure fluorine, provided a viable technique to eliminate uranium compound residue on the inside surface of the exhaust ducts. Typical uranium compound mass deposition per unit area of duct was 2 micron g/sq cm. This porous duct technique is directly applicable to future uranium compound transfer exhaust systems. Throughout these experiments, additional basic data on the corrosion aspects of hot, pressurized UF6/fluorine were also accumulated.

Lattice Boltzmann Study on Seawall-Break Flows under the Influence of Breach and Buildings

Science.gov (United States)

Mei, Qiu-Ying; Zhang, Wen-Huan; Wang, Yi-Hang; Chen, Wen-Wen

2017-10-01

In the process of storm surge, the seawater often overflows and even destroys the seawall. The buildings near the shore are usually inundated by the seawater through the breach. However, at present, there is little study focusing on the effects of buildings and breach on the seawall-break flows. In this paper, the lattice Boltzmann (LB) model with nine velocities in two dimensions (D2Q9) for the shallow water equations is adopted to simulate the seawall-break flows. The flow patterns and water depth distributions for the seawall-break flows under various densities, layouts and shapes of buildings and different breach discharges, sizes and locations are investigated. It is found that when buildings with a high enough density are perpendicular to the main flow direction, an obvious backwater phenomenon appears near buildings while this phenomenon does not occur when buildings with the same density are parallel to the main flow direction. Moreover, it is observed that the occurrence of backwater phenomenon is independent of the building shape. As to the effects of breach on the seawall-break flows, it is found that only when the breach discharge is large enough or the breach size is small enough, the effects of asymmetric distribution of buildings on the seawall-break flows become important. The breach location only changes the flow pattern in the upstream area of the first building that seawater meets, but has little impact on the global water depth distribution. Supported by the National Natural Science Foundation of China under Grant No. 11502124, the Natural Science Foundation of Zhejiang Province under Grant No. LQ16A020001, the Scientific Research Fund of Zhejiang Provincial Education Department under Grant No. Y201533808, the Natural Science Foundation of Ningbo under Grant No. 2016A610075, and is sponsored by K.C. Wong Magna Fund in Ningbo University.

Do promises matter? An exploration of the role of promises in psychological contract breach.

Science.gov (United States)

Montes, Samantha D; Zweig, David

2009-09-01

Promises are positioned centrally in the study of psychological contract breach and are argued to distinguish psychological contracts from related constructs, such as employee expectations. However, because the effects of promises and delivered inducements are confounded in most research, the role of promises in perceptions of, and reactions to, breach remains unclear. If promises are not an important determinant of employee perceptions, emotions, and behavioral intentions, this would suggest that the psychological contract breach construct might lack utility. To assess the unique role of promises, the authors manipulated promises and delivered inducements separately in hypothetical scenarios in Studies 1 (558 undergraduates) and 2 (441 employees), and they measured them separately (longitudinally) in Study 3 (383 employees). The authors' results indicate that breach perceptions do not represent a discrepancy between what employees believe they were promised and were given. In fact, breach perceptions can exist in the absence of promises. Further, promises play a negligible role in predicting feelings of violation and behavioral intentions. Contrary to the extant literature, the authors' findings suggest that promises may matter little; employees are concerned primarily with what the organization delivers.

Are Emotions Transmitted From Work to Family? A Crossover Model of Psychological Contract Breach.

Science.gov (United States)

Liang, Huai-Liang

2018-01-01

Based on affective events theory and the crossover model, this study examines the effect of psychological contract breach on employee dysfunctional behavior and partner family undermining and explores the crossover effect of employee dysfunctional behavior on partner family undermining in work-family issues. This study collected 370 employee-partner dyads (277 male employees, 93 female employees, M age = 43.59 years) from a large manufacturing organization. The results of this study support the conception that employees' psychological contract breach results in frustration in the workplace. In addition, mediation analysis results reveal that psychological contract breach relates to employee dysfunctional behavior in the workplace. The findings show that partners' psychological strain mediates the relationship between employee dysfunctional behavior and partner family undermining. Furthermore, these findings provide investigations for the crossover model to display the value of psychological contract breach in family issues.

Review of models used for determining consequences of UF6 release: Development of model evaluation criteria. Volume 1

International Nuclear Information System (INIS)

Nair, S.K.; Chambers, D.B.; Park, S.H.; Hoffman, F.O.

1997-11-01

The objective of this study is to examine the usefulness and effectiveness of currently existing models that simulate the release of uranium hexafluoride from UF 6 -handling facilities, subsequent reactions of UF 6 with atmospheric moisture, and the dispersion of UF 6 and reaction products in the atmosphere. The study evaluates screening-level and detailed public-domain models that were specifically developed for UF 6 and models that were originally developed for the treatment of dense gases but are applicable to UF 6 release, reaction, and dispersion. The model evaluation process is divided into three specific tasks: model-component evaluation; applicability evaluation; and user interface and quality assurance and quality control (QA/QC) evaluation. Within the model-component evaluation process, a model's treatment of source term, thermodynamics, and atmospheric dispersion are considered and model predictions are compared with actual observations. Within the applicability evaluation process, a model's applicability to Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis, and to site-specific considerations are assessed. Finally, within the user interface and QA/QC evaluation process, a model's user-friendliness, presence and clarity of documentation, ease of use, etc. are assessed, along with its handling of QA/QC. This document presents the complete methodology used in the evaluation process

Nuclear criticality safety aspects of gaseous uranium hexafluoride (UF6) in the diffusion cascade

International Nuclear Information System (INIS)

Huffer, J.E.

1997-04-01

This paper determines the nuclear safety of gaseous UF 6 in the current Gaseous Diffusion Cascade and auxiliary systems. The actual plant safety system settings for pressure trip points are used to determine the maximum amount of HF moderation in the process gas, as well as the corresponding atomic number densities. These inputs are used in KENO V.a criticality safety models which are sized to the actual plant equipment. The ENO V.a calculation results confirm nuclear safety of gaseous UF 6 in plant operations

Legal Effect of Breach of Warranty in Construction Insurance in Malaysia

OpenAIRE

Arazi Idrus; Mahmoud Sodangi; Jamaluddin Yaakob

2011-01-01

This study is aimed at analyzing the legal effect of breach of warranty in construction insurance contracts in Malaysia in light of the current developments in The English insurance law. The required data and information were collected from Malaysian and English court decisions dealing with breach of warranties in English marine insurance law from the online Malayan Law Journal published on the LexisNexis online database and from published textbooks related to insurance warranties. This study...

Assessment of Reusing 14-Ton, Thin-Wall, Depleted UF6 Cylinders as LLW Disposal Containers

International Nuclear Information System (INIS)

O'Connor, D.G.; Poole, A.B.; Shelton, J.H.

2000-01-01

Approximately 700,000 MT of DUF 6 is stored, or will be produced under a current agreement with the USEC, at the Paducah site in Kentucky, Portsmouth site in Ohio, and ETTP site in Tennessee. On July 21, 1998, the 105th Congress approved Public Law 105-204, which directed that facilities be built at the Kentucky and Ohio sites to convert DUF 6 to a stable form for disposition. On July 6, 1999, the Department of Energy (DOE) issued the ''Final Plan for the Conversion of Depleted Uranium Hexafluoride as Required by Public Law 105-204'', in which DOE committed to develop a ''Depleted Uranium Hexafluoride Materials Use Roadmap''. On September 1,2000, DOE issued the ''Draft Depleted Uranium Hexafluoride Materials Use Roadmap'' (Roadmap), which provides alternate paths for the long-term storage, beneficial use, and eventual disposition of each product form and material that will result from the DUF 6 conversion activity. One of the paths being considered for DUF 6 cylinders is to reuse the empty cylinders as containers to transport and dispose of LLW, including the converted DU. The Roadmap provides results of the many alternate uses and disposal paths for conversion products and the empty DUF 6 storage cylinders. As a part of the Roadmap, evaluations were conducted of cost savings, technical maturity, barriers to implementation, and other impacts. Results of these evaluations indicate that using the DUF 6 j storage cylinders as LLW disposal containers could provide moderate cost savings due to the avoided cost of purchasing LLW packages and the avoided cost of disposing of the cylinders. No significant technical or institutional .issues were identified that.would make using cylinders as LLW packages less effective than other disposition paths. Over 58,000 cylinders have been used, or will be used, to store DUF 6 . Over 5 1,000 of those cylinders are 14TTW cylinders with a nominal wall thickness of 5/16-m (0.79 cm). These- 14TTW cylinders, which have a nominal diameter

UV dissociation of vibrationally excited UF6

International Nuclear Information System (INIS)

Alexandre, M.; Clerc, M.; Gagnon, R.; Gilbert, M.; Isnard, P.; Nectoux, P.; Rigny, P.; Weulersse, J.M.

1983-01-01

Before application of laser photodissociation of UF 6 to the separation of uranium isotopes becomes practical, isotopic selectivity should be optimized. We present here results on the cross sections involved in the irradiation of UF 6 simultaneously with infrared and ultraviolet lasers, as a function of wavelengths, fluence and temperature (at 293 K and 105 K, in an adiabatic expansion). The experiment uses a Nd 3+ YAG pumped lithium niobate optical parametric oscillator as a tunable 16 μ light source. Energies of the order of 1 mJ can be obtained with linewidths smaller than 0.1 cm - . The UV source used is based on ND 3+ YAG pumped dye laser and various frequency mixing schemes. At low temperature the frequency variation of the absorbed infrared energy per molecule depends markedly on the IR fluence phisub(IR) with a maximum value varying as phisub(IR)sup(-1/2) and a frequency extension far beyond the low level absorption spectrum. The absorbed vibrational energy leads to a change in the UV cross section comparable with the effect of a rise in temperature. Using this a model is put forward to express the isotopic selectivity 235 U/ 238 U as a function of UV wavelength and IR irradiation conditions. Experimental results agree with this model, and yield to maximum selectivity close to two [fr

Measurement of 235U content and flow of UF6 using delayed neutrons or gamma rays following induced fission

International Nuclear Information System (INIS)

Stromswold, D.C.; Peurrung, A.J.; Reeder, P.L.; Perkins, R.W.

1996-06-01

Feasibility experiments conducted at Pacific Northwest National Laboratory demonstrate that either delayed neutrons or energetic gamma rays from short-lived fission products can be used to monitor the blending of UF 6 gas streams. A 252 Cf neutron source was used to induce 235 U fission in a sample, and delayed neutrons and gamma rays were measured after the sample moved open-quotes down-stream.close quotes The experiments used a UO 2 powder that was transported down the pipe to simulate the flowing UF 6 gas. Computer modeling and analytic calculation extended the test results to a flowing UF 6 gas system. Neutron or gamma-ray measurements made at two downstream positions can be used to indicate both the 235 U content and UF 6 flow rate. Both the neutron and gamma-ray techniques have the benefits of simplicity and long-term reliability, combined with adequate sensitivity for low-intrusion monitoring of the blending process. Alternatively, measuring the neutron emission rate from (a, n) reactions in the UF 6 provides an approximate measure of the 235 U content without using a neutron source to induce fission

BREACHING THE SEXUAL BOUNDARIES IN THE DOCTOR–PATIENT RELATIONSHIP: SHOULD ENGLISH LAW RECOGNISE FIDUCIARY DUTIES?

Science.gov (United States)

Ost, Suzanne

2016-01-01

In this article, I argue that sexual exploitation in the doctor–patient relationship would be dealt with more appropriately by the law in England and Wales on the basis of a breach of fiduciary duty. Three different types of sexual boundary breaches are discussed, and the particular focus is on breaches where the patient's consent is obtained through inducement. I contend that current avenues of redress do not clearly catch this behaviour and, moreover, they fail to capture the essence of the wrong committed by the doctor—the knowing breach of trust for self-gain—and the calculated way in which consent is induced. Finally, I demonstrate that the fiduciary approach is compatible with the contemporary pro-patient autonomy model of the doctor–patient relationship. PMID:26846652

Laboratory and pilot-plant studies on the conversion of uranyl nitrate hexahydrate to UF6 by fluidized-bed processes

International Nuclear Information System (INIS)

Youngblood, E.L.; Urza, I.J.; Cathers, G.I.

1977-06-01

This report describes laboratory and pilot-plant studies on the conversion of uranyl nitrate hexahydrate (UNH) to UF 6 and on purification of the UF 6 . Experimental laboratory studies on the removal of residual nitrate from uranium trioxide (UO 3 ) calcine and the fluorination of technetium and subsequent sorption on MgF 2 were conducted to support the pilot-plant work. Two engineering-scale pilot plants utilizing fluidized-bed processes were constructed for equipment and process testing of the calcination of UNH to UO 3 and the direct fluorination of UO 3 to UF 6

Transport of natural UF6 in a challenging environment

International Nuclear Information System (INIS)

Chollet, P.; Presta, A.

2004-01-01

At the entrance of the nuclear fuel cycle, the front-end material transportation takes a major and specific place. After years of stability the landscape of front-end industry is going toward significant changes regarding capacity, implementation of new technologies, imbalance of conversion capacity between geographical areas with increasing volumes of natural UF6 to transport and transport issues such as new regulations and denial of shipments by liners and ports. Facing this evolution the front end-industry is re-organizing its environment to increase robustness of the logistical chain: by being active in industrial organizations such as WNTI and WNA to share technical views and develop licensed standard transport equipment usable worldwide by developing other safe and reliable comprehensive logistics solutions as an alternative to conventional transport means. Our paper will describe the solutions under review to meet nuclear fuel cycle companies expectations: qualification of several robust logistics systems chartered vessels for maritime transport of UF6 specific 20' flat racks for safer handling of 48Y cylinders with future thermal protections

Transport of natural UF6 in a challenging environment

Energy Technology Data Exchange (ETDEWEB)

Chollet, P.; Presta, A. [COGEMA Logistics (AREVA Group) (France)

2004-07-01

At the entrance of the nuclear fuel cycle, the front-end material transportation takes a major and specific place. After years of stability the landscape of front-end industry is going toward significant changes regarding capacity, implementation of new technologies, imbalance of conversion capacity between geographical areas with increasing volumes of natural UF6 to transport and transport issues such as new regulations and denial of shipments by liners and ports. Facing this evolution the front end-industry is re-organizing its environment to increase robustness of the logistical chain: by being active in industrial organizations such as WNTI and WNA to share technical views and develop licensed standard transport equipment usable worldwide by developing other safe and reliable comprehensive logistics solutions as an alternative to conventional transport means. Our paper will describe the solutions under review to meet nuclear fuel cycle companies expectations: qualification of several robust logistics systems chartered vessels for maritime transport of UF6 specific 20' flat racks for safer handling of 48Y cylinders with future thermal protections.

Manual on safe production, transport, handling and storage of uranium hexafluoride

International Nuclear Information System (INIS)

1994-11-01

This document includes a description of the physical, chemical and radiological properties of UF 6 and related products, including information concerning their production, handling, storage and transportation and the management of the wastes which result. All the operations of UF 6 management are considered form a safety point of view. The IAEA organized a series of meetings to consider the hazards of UF 6 transport since considerable quantities of depleted, natural and enriched UF 6 are transported between nuclear fuel sites. Storage of depleted UF 6 is another important issue. Factors affecting long term storage are presented, especially site choice and cylinder corrosion. Other topics such as waste management, quality assurance and emergency preparedness which contribute to the overall safety of UF 6 handling, are included. The intention of this document is to provide analysis of the safety implications of all stages of UF 6 operations and to draw attention to specific features and properties of importance. 38 refs, figs, tabs

Validation of the Cristallini Sampling Method for UF6 by High Precision Double-Spike Measurements

OpenAIRE

RICHTER STEPHAN; JAKOBSSON ULF; HIESS JOE; AMARAGGI D.

2017-01-01

The so-called "Cristallini Method" for sampling of UF6 by adsorption and hydrolysis in alumina pellets inside a fluorothene P-10 tube was developed by the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) several years ago. This method has several advantages compared to the currently used sampling method, for which UF6 is distilled into a stainless steel tube for transportation, with hydrolysis and isotopic analysis being performed after shipping to the analyt...

The Accuracy of the Sysmex UF-1000i in Urine Bacterial Detection Compared With the Standard Urine Analysis and Culture.

Science.gov (United States)

Erdman, Patrick; Anderson, Brian; Zacko, J Christopher; Taylor, Kirk; Donaldson, Keri

2017-11-01

- Urinary tract infections are characterized by the presence of microbial pathogens within the urinary tract. They represent one of the most common infections in hospitalized and clinic patients. - To model the parameters of the Sysmex UF-1000i to the gold standard, urine culture, and to compare the detection of dipstick leukocyte esterase and nitrates to urine cultures and UF-1000i results. - Data were compared from urine samples collected in sterile containers for bacterial culture and microscopic analysis. One sample was used to inoculate a 5% sheep blood agar and MacConkey agar plate using a 0.001-mL calibrated loop. The second sample was analyzed by urinalysis-associated microscopy. The media plates were investigated for growth after 18 to 24 hours of aerobic incubation at 37°C. The second sample was analyzed for bacteria and leukocytes with the Sysmex UF-1000i according to the manufacturer's guidelines. Three definitions for culture results, sensitivity, and specificity at different cutoff values were calculated for the UF-1000i. - The negative predictive value for any positive culture in the adult population included in the study was 95.5%, and the negative predictive value for positive cultures containing growth of 100 000 or more colony-forming units was 99.3% using the Sysmex UF-1000i. - Sysmex UF-1000i showed 98% sensitivity and 93.7% specificity with a 95.5% negative predictive value. Thus, a negative screen with the UF-1000i using defined thresholds for white blood cell counts and bacteria was likely to be a true negative, decreasing the need for presumptive antibiotics.

First TREAT transient overpower tests on U-Pu-Zr fuel: M5 and M6

International Nuclear Information System (INIS)

Robinson, W.R.; Bauer, T.H.; Wright, A.E.; Rhodes, E.A.; Stanford, G.S.; Klickman, A.E.

1987-01-01

Transient Reactor Test Facility (TREAT) tests M5 and M6 were the first transient overpower (TOP) test of the margin to cladding breach and prefailure elongation of metallic U-Pu-Zr ternary fuel, the reference fuel of the integral fast reactor concept. Similar tests on U-5 wt% Fs fueled Experimental Breeder Reactor (EBR)-II driver pins were previously performed and reported. Results from these earlier tests indicated a margin to failure of ∼ 4 times nominal power and significant axial elongation prior to failure, a feature that was very pronounced at low burnups. While these two fuels types are similar in many respects, the ternary alloy exhibits a much more complex physical structure and is typically irradiated at much higher temperatures. Thus, a prime motivation for performing M5 and M6 was to compare the safety-related fuel performance characteristics of U-Fs and U-Pu-Zr. Tests M5 and M6 indicate that, under the TOP conditions used in the tests, ternary fuel displayed about the same margin to failure as U-Fs fuel. At low burnups, ternary fuel showed less prefailure axial elongation than observed in U-Fs pins, but elongations of 3 to 5% might turn out to be typical. Finally, fuel from the breached ternary pin in M6 showed, qualitatively, the same benignly dispersive behavior as U-Fs

Benchmark calculation of APOLLO-2 and SLAROM-UF in a fast reactor lattice

International Nuclear Information System (INIS)

Hazama, T.

2009-07-01

A lattice cell benchmark calculation is carried out for APOLLO2 and SLAROM-UF on the infinite lattice of a simple pin cell featuring a fast reactor. The accuracy in k-infinity and reaction rates is investigated in their reference and standard level calculations. In the 1. reference level calculation, APOLLO2 and SLAROM-UF agree with the reference value of k-infinity obtained by a continuous energy Monte Carlo calculation within 50 pcm. However, larger errors are observed in a particular reaction rate and energy range. The major problem common to both codes is in the cross section library of 239 Pu in the unresolved energy range. In the 2. reference level calculation, which is based on the ECCO 1968 group structure, both results of k-infinity agree with the reference value within 100 pcm. The resonance overlap effect is observed by several percents in cross sections of heavy nuclides. In the standard level calculation based on the APOLLO2 library creation methodology, a discrepancy appears by more than 300 pcm. A restriction is revealed in APOLLO2. Its standard cross section library does not have a sufficiently small background cross section to evaluate the self shielding effect on 56 Fe cross sections. The restriction can be removed by introducing the mixture self-shielding treatment recently introduced to APOLLO2. SLAROM-UF original standard level calculation based on the JFS-3 library creation methodology is the best among the standard level calculations. Improvement from the SLAROM-UF standard level calculation is achieved mainly by use of a proper weight function for light or intermediate nuclides. (author)

Actual and Idealized Crystal Field Parameterizations for the Uranium Ions in UF 4

Science.gov (United States)

Gajek, Z.; Mulak, J.; Krupa, J. C.

1993-12-01

The crystal field parameters for the actual coordination symmetries of the uranium ions in UF 4, C2 and C1, and for their idealizations to D2, C2 v , D4, D4 d , and the Archimedean antiprism point symmetries are given. They have been calculated by means of both the perturbative ab initio model and the angular overlap model and are referenced to the recent results fitted by Carnall's group. The equivalency of some different sets of parameters has been verified with the standardization procedure. The adequacy of several idealized approaches has been tested by comparison of the corresponding splitting patterns of the 3H 4 ground state. Our results support the parameterization given by Carnall. Furthermore, the parameterization of the crystal field potential and the splitting diagram for the symmetryless uranium ion U( C1) are given. Having at our disposal the crystal field splittings for the two kinds of uranium ions in UF 4, U( C2) and U( C1), we calculate the model plots of the paramagnetic susceptibility χ( T) and the magnetic entropy associated with the Schottky anomaly Δ S( T) for UF 4.

The older, the better! Age-related differences in emotion regulation after psychological contract breach.

NARCIS (Netherlands)

Bal, P.M.; Smit, P.

2012-01-01

The aim of this paper was to investigate the role of emotion regulation and age in reactions to psychological contract breach towards positive and negative affect. The authors expected that in the context of contract breach, reappraisal emotion regulation mitigate the negative relation with affect.

Experimental Determination of the Solubility of Industrial UF4 Particles

International Nuclear Information System (INIS)

Chazel, V.; Houpert, P.; Paquet, F.; Ansoborlo, E.; Henge-Napoli, M.H.

2000-01-01

The chemical solubility in cell culture medium and in Gamble's solution and the biokinetic behaviour on rats of an industrial UF 4 compound have been studied in order to predict experimentally absorption parameters (f r , s r , s s ) after inhalation and to provide data for interpreting bioassay data. According to these results, this compound has been found to have an intermediate type of absorption between Types F and M as designated by ICRP for the human respiratory tract. A dose coefficient of 1.4 μSv.Bq -1 has been calculated for an inhaled aerosol with an AMAD of 5.1 μm (σg 2.5), which corresponded to the mean value encountered at the fluorination workplace. Predictive urinary and faecal excretion and lung retention curves have also been deduced to calculate the incorporated activity and the received dose in case of an inhalation of UF 4 by workers. (author)

Technology Assessment for Proof-of-Concept UF6 Cylinder Unique Identification Task 3.1.2 Report – Survey and Assessment of Technologies

Energy Technology Data Exchange (ETDEWEB)

Wylie, Joann; Hockert, John

2014-04-24

The National Nuclear Security Administration (NNSA) Office of Nonproliferation and International Security’s (NA-24) Next Generation Safeguards Initiative (NGSI) and the nuclear industry have begun to develop approaches to identify and monitor uranium hexafluoride (UF6) cylinders. The NA-24 interest in a global monitoring system for UF6 cylinders relates to its interest in supporting the International Atomic Energy Agency (IAEA) in deterring and detecting diversion of UF6 (e.g., loss of cylinder in transit) and undeclared excess production at conversion and enrichment facilities. The industry interest in a global monitoring system for UF6 cylinders relates to the improvements in operational efficiencies that such a system would provide. This task is part of an effort to survey and assess technologies for a UF6 cylinder to identify candidate technologies for a proof-of-concept demonstration and evaluation for the Cylinder Identification System (CIS).

Presentation and interpretation of field experiments of gaseous UF{sub 6} releases in the atmosphere

Energy Technology Data Exchange (ETDEWEB)

Crabol, B.; Boulaud, D.; Deville-Cavelin, G. [CEA/Inst. de Protection et de Surete Nucleaire, Dept. de Protection de l' Environnement et des Installations, Fontenay-aux-Roses (France); Geisse, C.; Iacona, L. [EURODIF/Production, Site de Tricastin, Pierrelatte Cedex (France)

1992-07-01

An experimental programme concerning the behaviour of UF{sub 6} released in gaseous phase in the atmosphere has been conducted in the years 1986-1989 by the French Atomic Energy Commission and EURODIF. Three field tests have been performed on the CEA/CESTA experimental site. These experiments permitted to get information about the kinetics of the hydrolysis reaction of the UF{sub 6}, the behaviour of the hydrolysis products in the atmosphere and the granulometry of the solid particles. (author)

Modelling of HTR Confinement Behaviour during Accidents Involving Breach of the Helium Pressure Boundary

Directory of Open Access Journals (Sweden)

Joan Fontanet

2009-01-01

Full Text Available Development of HTRs requires the performance of a thorough safety study, which includes accident analyses. Confinement building performance is a key element of the system since the behaviour of aerosol and attached fission products within the building is of an utmost relevance in terms of the potential source term to the environment. This paper explores the available simulation capabilities (ASTEC and CONTAIN codes and illustrates the performance of a postulated HTR vented confinement under prototypical accident conditions by a scoping study based on two accident sequences characterized by Helium Pressure Boundary breaches, a small and a large break. The results obtained indicate that both codes predict very similar thermal-hydraulic responses of the confinement both in magnitude and timing. As for the aerosol behaviour, both codes predict that most of the inventory coming into the confinement is eventually depleted on the walls and only about 1% of the aerosol dust is released to the environment. The crosscomparison of codes states that largest differences are in the intercompartmental flows and the in-compartment gas composition.

Tight ceramic UF membrane as RO pre-treatment: the role of electrostatic interactions on phosphate rejection.

Science.gov (United States)

Shang, Ran; Verliefde, Arne R D; Hu, Jingyi; Zeng, Zheyi; Lu, Jie; Kemperman, Antoine J B; Deng, Huiping; Nijmeijer, Kitty; Heijman, Sebastiaan G J; Rietveld, Luuk C

2014-01-01

Phosphate limitation has been reported as an effective approach to inhibit biofouling in reverse osmosis (RO) systems for water purification. The rejection of dissolved phosphate by negatively charged TiO2 tight ultrafiltration (UF) membranes (1 kDa and 3 kDa) was observed. These membranes can potentially be adopted as an effective process for RO pre-treatment in order to constrain biofouling by phosphate limitation. This paper focuses on electrostatic interactions during tight UF filtration. Despite the larger pore size, the 3 kDa ceramic membrane exhibited greater phosphate rejection than the 1 kDa membrane, because the 3 kDa membrane has a greater negative surface charge and thus greater electrostatic repulsion against phosphate. The increase of pH from 6 to 8.5 led to a substantial increase in phosphate rejection by both membranes due to increased electrostatic repulsion. At pH 8.5, the maximum phosphate rejections achieved by the 1 kDa and 3 kDa membrane were 75% and 86%, respectively. A Debye ratio (ratio of the Debye length to the pore radius) is introduced in order to evaluate double layer overlapping in tight UF membranes. Threshold Debye ratios were determined as 2 and 1 for the 1 kDa and 3 kDa membranes, respectively. A Debye ratio below the threshold Debye ratio leads to dramatically decreased phosphate rejection by tight UF membranes. The phosphate rejection by the tight UF, in combination with chemical phosphate removal by coagulation, might accomplish phosphate-limited conditions for biological growth and thus prevent biofouling in the RO systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

Psychological contract breach and job attitudes : A meta-analysis of age as a moderator

NARCIS (Netherlands)

Bal, P. Matthijs; De lange, Annet H.; Jansen, Paul G. W.; Van der Velde, Mandy E. G.

The aim of this study was to examine the influence of age in the relation between psychological contract breach and the development of job attitudes. Based on affective events, social exchange, and lifespan theory, we hypothesized that (1) psychological contract breach would be related negatively to

Modelling of the behaviour of a UF_6 container in a fire

International Nuclear Information System (INIS)

Pinton, Eric

1996-01-01

This thesis is justified by the safety needs about storage and transport of UF_6 containers. To define their behaviour under fire conditions, a modelling was developed. Before tackling the numerical modelling, a phenomenological interpretation with experimental results of containers inside a furnace (800 C) during a fixed period was carried out. The internal heat transfers were considerably improved with these results. The 2D elaborated model takes into account most of the physical phenomena encountered in this type of situation (boiling, evaporation, condensation, radiant heat transfers through an absorbing gas, convection, pressurisation, thermal contact resistance, UF_6 expansion, solid core sinking in the liquid, elastic and plastic deformations of the steel container). This model was successfully confronted with experiments. (author) [fr

Radiation-Triggered Surveillance for UF6 Monitoring

Energy Technology Data Exchange (ETDEWEB)

Curtis, Michael M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-12-01

This paper recommends the use of radiation detectors, singly or in sets, to trigger surveillance cameras. Ideally, the cameras will monitor cylinders transiting the process area as well as the process area itself. The general process area will be surveyed to record how many cylinders have been attached and detached to the process between inspections. Rad-triggered cameras can dramatically reduce the quantity of recorded images, because the movement of personnel and equipment not involving UF6 cylinders will not generate a surveillance review file.

Joint Precision Approach and Landing System Nunn-McCurdy Breach Root Cause Analysis and Portfolio Assessment Metrics for DOD Weapons Systems. Volume 8

Science.gov (United States)

2016-01-01

ABP breaches Quantity changes > 5% PAUC growth Pre- Milestone C > 5% APUC growth 100 60 80 40 0 % 0 2012 ABP breaches Quantity changes > 5% PAUC growth...Pre- Milestone C > 5% APUC growth 100 60 80 40 % 2003 ABP breaches Nunn- McCurdy breaches Nunn- McCurdy breaches Nunn- McCurdy breaches Nunn- McCurdy...Quantity changes > 5% PAUC growth > 5% APUC growth Pre- Milestone C% 100 60 80 40 0 2004 ABP breaches Quantity changes > 5%

Measuring information security breach impact and uncertainties under various information sharing scenarios

OpenAIRE

Durowoju, Olatunde; Chan, Hing; Wang, Xiaojun

2013-01-01

This study draws on information theory and aims to provide simulated evidence using real historical and statistical data to demonstrate how various levels of integration moderate the impact and uncertainties of information security breach on supply chain performance. We find that the supply chain behaves differently under various levels of integration when a security breach occurs. The entropy analysis revealed that the wholesaler experience the most uncertainty under system failure and data ...

Heat transfer characteristics of UF6 in a container heated from outer surface. Pt. 1. Thermal hydraulic analysis method taking account of phase change and volume expansion

International Nuclear Information System (INIS)

Wataru, Masumi; Gomi, Yoshio; Yamakawa, Hidetsugu; Tsumune, Daisuke

1995-01-01

Natural UF6 is transported in a steel container from foreign countries to the enrichment plant in Japan. If the container meets fire accident, it is heated by fire (800degC) and rupture of the container may occur. For the safety point of view, it is necessary to know whether rupture occurs or not. Because UF6 has a radiological and chemical hazards, it is difficult to perform a demonstration test with UF6. So thermal calculation method has to be developed. The rupture is caused by UF6 gaseous pressure or volume expansion of liquid UF6. To know time history of internal pressure and temperature distribution in the container, it is important to evaluate thermal phenomena of UF6. When UF6 is heated, it changes from solid to liquid or gas at low temperature (64degC) and then its volume expands little by little. In this study, thermal calculation method has been developed taking phase change and thermal expansion of UF6 into account. In the calculation, a two-dimensional model is adopted and natural convection of liquid UF6 is analyzed. As a result of this study, numerical solutions have been obtained taking phase change and volume expansion into account. (author)

Thermodynamic assessment of the LiF–ThF{sub 4}–PuF{sub 3}–UF{sub 4} system

Energy Technology Data Exchange (ETDEWEB)

Capelli, E. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Department of Radiation Science and Technology, Faculty of Applied Physics, Delft University of Technology, Delft 2629JB (Netherlands); Beneš, O., E-mail: ondrej.benes@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Konings, R.J.M. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Department of Radiation Science and Technology, Faculty of Applied Physics, Delft University of Technology, Delft 2629JB (Netherlands)

2015-07-15

The LiF–ThF{sub 4}–PuF{sub 3}–UF{sub 4} system is the reference salt mixture considered for the Molten Salt Fast Reactor (MSFR) concept started with PuF{sub 3}. In order to obtain the complete thermodynamic description of this quaternary system, two binary systems (ThF{sub 4}–PuF{sub 3} and UF{sub 4}–PuF{sub 3}) and two ternary systems (LiF–ThF{sub 4}–PuF{sub 3} and LiF–UF{sub 4}–PuF{sub 3}) have been assessed for the first time. The similarities between CeF{sub 3}/PuF{sub 3} and ThF{sub 4}/UF{sub 4} compounds have been taken into account for the presented optimization as well as in the experimental measurements performed, which have confirmed the temperatures predicted by the model. Moreover, the experimental results and the thermodynamic database developed have been used to identify potential compositions for the MSFR fuel and to evaluate the influence of partial substitution of ThF{sub 4} by UF{sub 4} in the salt.

Expert system for surveillance and diagnosis of breach fuel elements

Science.gov (United States)

Gross, Kenny C.

1989-01-01

An apparatus and method are disclosed for surveillance and diagnosis of breached fuel elements in a nuclear reactor. A delayed neutron monitoring system provides output signals indicating the delayed neutron activity and age and the equivalent recoil areas of a breached fuel element. Sensors are used to provide outputs indicating the status of each component of the delayed neutron monitoring system. Detectors also generate output signals indicating the reactor power level and the primary coolant flow rate of the reactor. The outputs from the detectors and sensors are interfaced with an artificial intelligence-based knowledge system which implements predetermined logic and generates output signals indicating the operability of the reactor.

Expert system for surveillance and diagnosis of breach fuel elements

International Nuclear Information System (INIS)

Gross, K.C.

1989-01-01

An apparatus and method are disclosed for surveillance and diagnosis of breached fuel elements in a nuclear reactor. A delayed neutron monitoring system provides output signals indicating the delayed neutron activity and age and the equivalent recoil areas of a breached fuel element. Sensors are used to provide outputs indicating the status of each component of the delayed neutron monitoring system. Detectors also generate output signals indicating the reactor power level and the primary coolant flow rate of the reactor. The outputs from the detectors and sensors are interfaced with an artificial intelligence-based knowledge system which implements predetermined logic and generates output signals indicating the operability of the reactor

Radiation dose rates from UF{sub 6} cylinders

Energy Technology Data Exchange (ETDEWEB)

Friend, P.J. [Urenco, Capenhurst (United Kingdom)

1991-12-31

This paper describes the results of many studies, both theoretical and experimental, which have been carried out by Urenco over the last 15 years into radiation dose rates from uranium hexafluoride (UF{sub 6}) cylinders. The contents of the cylinder, its history, and the geometry all affect the radiation dose rate. These factors are all examined in detail. Actual and predicted dose rates are compared with levels permitted by IAEA transport regulations.

Thermodynamic assessment of the LiF–ThF4–PuF3–UF4 system

NARCIS (Netherlands)

Capelli, E.; Benes, O.; Konings, R.J.M.

2015-01-01

The LiF–ThF4–PuF3–UF4 system is the reference salt mixture considered for the Molten Salt Fast Reactor (MSFR) concept started with PuF3. In order to obtain the complete thermodynamic description of this quaternary system, two binary systems (ThF4–PuF3 and UF4–PuF3) and two ternary systems

I Am So Tired… How Fatigue May Exacerbate Stress Reactions to Psychological Contract Breach

Directory of Open Access Journals (Sweden)

Safâa Achnak

2018-03-01

Full Text Available Previous research showed that perceptions of psychological contract (PC breach have undesirable individual and organizational consequences. Surprisingly, the PC literature has paid little to no attention to the relationship between PC breach perceptions and stress. A better understanding of how PC breach may elicit stress seems crucial, given that stress plays a key role in employees' physical and mental well-being. Based on Conservation of Resources Theory, we suggest that PC breach perceptions represent a perceived loss of valued resources, subsequently leading employees to experience higher stress levels resulting from emerging negative emotions. Moreover, we suggest that this mediated relationship is moderated by initial levels of fatigue, due to fatigue lowering the personal resources necessary to cope with breach events. To tests our hypotheses, we analyzed the multilevel data we obtained from two experience sampling designs (Study 1: 51 Belgian employees; Study 2: 53 US employees. Note that the unit of analysis is “observations” rather than “respondents,” resulting in an effective sample size of 730 (Study 1 and 374 (Study 2 observations. In both studies, we found evidence for the mediating role of negative emotions in the PC breach—stress relationship. In the second study, we also found evidence for the moderating role of fatigue in the mediated PC breach—stress relationship. Implications for research and practice are discussed.

I Am So Tired… How Fatigue May Exacerbate Stress Reactions to Psychological Contract Breach

Science.gov (United States)

Achnak, Safâa; Griep, Yannick; Vantilborgh, Tim

2018-01-01

Previous research showed that perceptions of psychological contract (PC) breach have undesirable individual and organizational consequences. Surprisingly, the PC literature has paid little to no attention to the relationship between PC breach perceptions and stress. A better understanding of how PC breach may elicit stress seems crucial, given that stress plays a key role in employees' physical and mental well-being. Based on Conservation of Resources Theory, we suggest that PC breach perceptions represent a perceived loss of valued resources, subsequently leading employees to experience higher stress levels resulting from emerging negative emotions. Moreover, we suggest that this mediated relationship is moderated by initial levels of fatigue, due to fatigue lowering the personal resources necessary to cope with breach events. To tests our hypotheses, we analyzed the multilevel data we obtained from two experience sampling designs (Study 1: 51 Belgian employees; Study 2: 53 US employees). Note that the unit of analysis is “observations” rather than “respondents,” resulting in an effective sample size of 730 (Study 1) and 374 (Study 2) observations. In both studies, we found evidence for the mediating role of negative emotions in the PC breach—stress relationship. In the second study, we also found evidence for the moderating role of fatigue in the mediated PC breach—stress relationship. Implications for research and practice are discussed. PMID:29559935

(PACS) data security breaches: Intentional versus non-intentional ...

African Journals Online (AJOL)

Background: The Picture Archiving and Communication System (PACS) has led to an increase in breached health records and violation of patient confidentiality. The South African constitution makes provision for human dignity and privacy, virtues which confidentiality seeks to preserve. Confidentiality thus constitutes a ...

Conversion of non-nuclear grade feedstock to UF4

International Nuclear Information System (INIS)

Ponelis, A.A.; Slabber, M.N.; Zimmer, C.H.E.

1987-01-01

The South African Conversion route is based on the direct feed of ammonium di-uranate produced by any one of a number of different mines. The physical and chemical characteristics of the feedstock can thus vary considerably and influence the conversion rate as well as the final UF 6 product purity. The UF 4 conversion reactor is a Moving Bed Reactor (MBR) with countercurrent flow of the reacting gas phases. Initial problems to continuously operate the MBR were mostly concerned with the physical nature of the UO 3 feed particles. Different approaches to eventually obtain a successful MBR are discussed. Besides obtaining UO 3 feed particles with certain physical attributes, the chemical impurities also have an effect on the operability of the MBR. The influence of the feedstock variables on the reduction and hydrofluorination rates after calcining has largely been determined from laboratory and pilot studies. The effect of chemical impurities such as sodium and potassium on the sinterability of the reacting particles and therefore the optimum temperature range in the MBR is also discussed. Confirmation of the effect of sodium and potassium impurities on the conversion rate has been obtained from large scale reactor operation. (author)

Hydraulics of embankment-dam breaching

Science.gov (United States)

Walder, J. S.; Iverson, R. M.; Logan, M.; Godt, J. W.; Solovitz, S.

2012-12-01

Constructed or natural earthen dams can pose hazards to downstream communities. Experiments to date on earthen-dam breaching have focused on dam geometries relevant to engineering practice. We have begun experiments with dam geometries more like those of natural dams. Water was impounded behind dams constructed at the downstream end of the USGS debris-flow flume. Dams were made of compacted, well-sorted, moist beach sand (D50=0.21 mm), 3.5 m from toe to toe, but varying in height from 0.5 to 1 m; the lower the dam, the smaller the reservoir volume and the broader the initially flat crest. Breaching was started by cutting a slot 30-40 mm wide and deep in the dam crest after filling the reservoir. Water level and pore pressure within the dam were monitored. Experiments were also recorded by an array of still- and video cameras above the flume and a submerged video camera pointed at the upstream dam face. Photogrammetric software was used to create DEMs from stereo pairs, and particle-image velocimetry was used to compute the surface-velocity field from the motion of tracers scattered on the water surface. As noted by others, breaching involves formation and migration of a knickpoint (or several). Once the knickpoint reaches the upstream dam face, it takes on an arcuate form whose continued migration we determined by measuring the onset of motion of colored markers on the dam face. The arcuate feature, which can be considered the head of the "breach channel", is nearly coincident with the transition from subcritical to supercritical flow; that is, it acts as a weir that hydraulically controls reservoir emptying. Photogenic slope failures farther downstream, although the morphologically dominant process at work, play no role at all in hydraulic control aside from rare instances in which they extend upstream so far as to perturb the weir, where the flow cross section is nearly self-similar through time. The domain downstream of the critical-flow section does influence

A socio-emotional selectivity perspective on age-related differences in reactions to psychological contract breach

NARCIS (Netherlands)

Matthijs Bal; Paul Jansen; Annet de Lange; Mandy van der Velde

2013-01-01

The current paper investigated age-related differences in the relations of psychological contract breach with work outcomes over time. Based on affective events theory, we expected job satisfaction to mediate the longitudinal relationship of contract breach with changes in job performance. Moreover,

Nuclear criticality safety aspects of gaseous uranium hexafluoride (UF{sub 6}) in the diffusion cascade

Energy Technology Data Exchange (ETDEWEB)

Huffer, J.E. [Parallax, Inc., Atlanta, GA (United States)

1997-04-01

This paper determines the nuclear safety of gaseous UF{sub 6} in the current Gaseous Diffusion Cascade and auxiliary systems. The actual plant safety system settings for pressure trip points are used to determine the maximum amount of HF moderation in the process gas, as well as the corresponding atomic number densities. These inputs are used in KENO V.a criticality safety models which are sized to the actual plant equipment. The ENO V.a calculation results confirm nuclear safety of gaseous UF{sub 6} in plant operations..

UF6 Density and Mass Flow Measurements for Enrichment Plants using Acoustic Techniques

Energy Technology Data Exchange (ETDEWEB)

Good, Morris S.; Smith, Leon E.; Warren, Glen A.; Jones, Anthony M.; Ramuhalli, Pradeep; Roy, Surajit; Moran, Traci L.; Denslow, Kayte M.; Longoni, Gianluca

2017-09-01

A key enabling capability for enrichment plant safeguards being considered by the International Atomic Energy Agency (IAEA) is high-accuracy, noninvasive, unattended measurement of UF6 gas density and mass flow rate. Acoustic techniques are currently used to noninvasively monitor gas flow in industrial applications; however, the operating pressures at gaseous centrifuge enrichment plants (GCEPs) are roughly two orders magnitude below the capabilities of commercial instrumentation. Pacific Northwest National Laboratory is refining acoustic techniques for estimating density and mass flow rate of UF6 gas in scenarios typical of GCEPs, with the goal of achieving 1% measurement accuracy. Proof-of-concept laboratory measurements using a surrogate gas for UF6 have demonstrated signatures sensitive to gas density at low operating pressures such as 10–50 Torr, which were observed over the background acoustic interference. Current efforts involve developing a test bed for conducting acoustic measurements on flowing SF6 gas at representative flow rates and pressures to ascertain the viability of conducting gas flow measurements under these conditions. Density and flow measurements will be conducted to support the evaluation. If successful, the approach could enable an unattended, noninvasive approach to measure mass flow in unit header pipes of GCEPs.

An approach for estimating the breach probabilities of moraine-dammed lakes in the Chinese Himalayas using remote-sensing data

Directory of Open Access Journals (Sweden)

X. Wang

2012-10-01

Full Text Available To make first-order estimates of the probability of moraine-dammed lake outburst flood (MDLOF and prioritize the probabilities of breaching posed by potentially dangerous moraine-dammed lakes (PDMDLs in the Chinese Himalayas, an objective approach is presented. We first select five indicators to identify PDMDLs according to four predesigned criteria. The climatic background was regarded as the climatic precondition of the moraine-dam failure, and under different climatic preconditions, we distinguish the trigger mechanisms of MDLOFs and subdivide them into 17 possible breach modes, with each mode having three or four components; we combined the precondition, modes and components to construct a decision-making tree of moraine-dam failure. Conversion guidelines were established so as to quantify the probabilities of components of a breach mode employing the historic performance method combined with expert knowledge and experience. The region of the Chinese Himalayas was chosen as a study area where there have been frequent MDLOFs in recent decades. The results show that the breaching probabilities (P of 142 PDMDLs range from 0.037 to 0.345, and they can be further categorized as 43 lakes with very high breach probabilities (P ≥ 0.24, 47 lakes with high breach probabilities (0.18 ≤ P < 0.24, 24 lakes with mid-level breach probabilities (0.12 ≤ P < 0.18, 24 lakes with low breach probabilities (0.06 ≤ P < 0.12, and four lakes with very low breach probabilities (p < 0.06.

Psychological Contract Breach and Job Attitudes: A Meta-Analysis of Age as a Moderator

Science.gov (United States)

Bal, P. Matthijs; De Lange, Annet H.; Jansen, Paul G. W.; Van Der Velde, Mandy E. G.

2008-01-01

The aim of this study was to examine the influence of age in the relation between psychological contract breach and the development of job attitudes. Based on affective events, social exchange, and lifespan theory, we hypothesized that (1) psychological contract breach would be related negatively to job attitudes, and (2) that age would moderate…

Manual on safe production, transport, handling and storage of uranium hexafluoride

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-11-01

This document includes a description of the physical, chemical and radiological properties of UF{sub 6} and related products, including information concerning their production, handling, storage and transportation and the management of the wastes which result. All the operations of UF{sub 6} management are considered form a safety point of view. The IAEA organized a series of meetings to consider the hazards of UF{sub 6} transport since considerable quantities of depleted, natural and enriched UF{sub 6} are transported between nuclear fuel sites. Storage of depleted UF{sub 6} is another important issue. Factors affecting long term storage are presented, especially site choice and cylinder corrosion. Other topics such as waste management, quality assurance and emergency preparedness which contribute to the overall safety of UF{sub 6} handling, are included. The intention of this document is to provide analysis of the safety implications of all stages of UF{sub 6} operations and to draw attention to specific features and properties of importance. 38 refs, figs, tabs.

Laboratory and pilot-plant studies on the conversion of uranyl nitrate hexahydrate to UF/sub 6/ by fluidized-bed processes

Energy Technology Data Exchange (ETDEWEB)

Youngblood, E.L.; Urza, I.J.; Cathers, G.I.

1977-06-01

This report describes laboratory and pilot-plant studies on the conversion of uranyl nitrate hexahydrate (UNH) to UF/sub 6/ and on purification of the UF/sub 6/. Experimental laboratory studies on the removal of residual nitrate from uranium trioxide (UO/sub 3/) calcine and the fluorination of technetium and subsequent sorption on MgF/sub 2/ were conducted to support the pilot-plant work. Two engineering-scale pilot plants utilizing fluidized-bed processes were constructed for equipment and process testing of the calcination of UNH to UO/sub 3/ and the direct fluorination of UO/sub 3/ to UF/sub 6/.

Materials considerations for UF6 gas-core reactor. Interim report for preliminary design study

International Nuclear Information System (INIS)

Wagner, P.

1977-04-01

The limiting materials problem in a high-temperature UF 6 core reactor is the corrosion of the core containment vessel. The UF 6 , the lower fluorides of uranium, and the fluorine that exist at the anticipated reactor operating conditions (1000 K and about one atmosphere UF 6 ) are all corrosive. Because of this, the materials evaluation effort for this reactor design study has concentrated on the identification of a viable system for the containment vessel that meets both the materials and neutronic requirements. A study of the literature has revealed that the most promising corrosion-resistant candidates are Ni or Ni-Al alloys. One of the conclusions of this work is that the containment vessel use a nickel liner or clad since the use of Ni as a structural member is precluded by its relative blackness to thermal neutrons. Estimates of corrosion rates of Ni and Ni-Al alloys, the effects of the pressure and temperature of F 2 on the corrosion rates, calculated equilibrium gas compositions at reactor core operating conditions, suggested methods of fabrication, and recommendations for future research and development are included

A 1D coordination polymer of UF{sub 5} with HCN as a ligand

Energy Technology Data Exchange (ETDEWEB)

Scheibe, Benjamin; Rudel, Stefan S.; Buchner, Magnus R.; Kraus, Florian [Fachbereich Chemie, Philipps-Universitaet Marburg (Germany); Karttunen, Antti J. [Department of Chemistry, Aalto University (Finland)

2017-01-05

β-Uranium(V) fluoride was reacted with liquid anhydrous hydrogen cyanide to obtain a 1D coordination polymer with the composition {sup 1}{sub ∞}[UF{sub 5}(HCN){sub 2}], {sup 1}{sub ∞}[UF{sub 4/1}F{sub 2/2}-(HCN){sub 2/1}], revealed by single-crystal X-ray structure determination. The reaction system was furthermore studied by means of vibrational and NMR spectroscopy, as well as by quantum chemical calculations. The compound presents the first described polymeric HCN Lewis adduct and the first HCN adduct of a uranium fluoride. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

Scoping study to expedite development of a field deployable and portable instrument for UF6 enrichment assay

OpenAIRE

Chan, CYG; Valentine, JD; Russo, RE

2017-01-01

The primary objective of the present study is to identity the most promising, viable technologies that are likely to culminate in an expedited development of the next-generation, field-deployable instrument for providing rapid, accurate, and precise enrichment assay of uranium hexafluoride (UF6). UF6 is typically involved, and is arguably the most important uranium compound, in uranium enrichment processes. As the first line of defense against proliferation, accurate analytical techniques t...

Sampling and characterization of aerosols formed in the atmospheric hydrolysis of UF6

International Nuclear Information System (INIS)

Bostick, W.D.; McCulla, W.H.; Pickrell, P.W.; Branam, D.A.

1983-01-01

When gaseous UF 6 is released into the atmosphere, it rapidly reacts with ambient moisture to form an aerosol of uranyl fluoride and HF. As part of our Safety Analysis program, we have performed several experimental releases of UF 6 (from natural uranium) in contained volumes in order to investigate techniques for sampling and characterizing the aerosol materials. The aggregrate particle morphology and size distribution have been found to be dependent upon several conditions, including the relative humidity at the time of the release and the elapse time after the release. Aerosol composition and settling rate have been investigated using isokinetic samplers for the separate collection of UO 2 F 2 and HF, and via laser spectroscopic remote sensing (Mie scatter and infrared spectroscopy). 8 references

THERMOPHYSICAL PROPERTIES AND WATER ACTIVITY OF TRANSFERRED CHEESE (UF

Directory of Open Access Journals (Sweden)

Mohsen Dalvi Esfahan

2015-06-01

Full Text Available Few data are available on the thermophysical properties of cheese in the ripening process.The main objective of this work was to investigate the effects of brining and temperature on the thermophysical properties, i.e., thermal conductivity, specific heat, density and water activity of UF cheese and finally we measure surface heat transfer coefficient .Then we develop models for thermophysical properties based on physical and multiple regression concept .

The Role of HIPAA Omnibus Rules in Reducing the Frequency of Medical Data Breaches: Insights From an Empirical Study.

Science.gov (United States)

Yaraghi, Niam; Gopal, Ram D

2018-03-01

Policy Points: Frequent data breaches in the US health care system undermine the privacy of millions of patients every year-a large number of which happen among business associates of the health care providers that continue to gain unprecedented access to patients' data as the US health care system becomes digitally integrated. Implementation of the HIPAA Omnibus Rules in 2013 has led to a significant decrease in the number of privacy breach incidents among business associates. Frequent data breaches in the US health care system undermine the privacy of millions of patients every year. A large number of such breaches happens among business associates of the health care providers that continue to gain unprecedented access to patients' data as the US health care system becomes digitally integrated. The Omnibus Rules of the Health Insurance Portability and Accountability Act (HIPAA), which were enacted in 2013, significantly increased the regulatory oversight and privacy protection requirements of business associates. The objective of this study is to empirically examine the effects of this shift in policy on the frequency of medical privacy breaches among business associates in the US health care system. The findings of this research shed light on how regulatory efforts can protect patients' privacy. Using publicly available data on breach incidents between October 2009 and August 2017 as reported by the Office for Civil Rights (OCR), we conducted an interrupted time-series analysis and a difference-in-differences analysis to examine the immediate and long-term effects of implementation of HIPAA omnibus rules on the frequency of medical privacy breaches. We show that implementation of the omnibus rules led to a significant reduction in the number of breaches among business associates and prevented 180 privacy breaches from happening, which could have affected nearly 18 million Americans. Implementation of HIPAA omnibus rules may have been a successful federal policy

After the data breach: Managing the crisis and mitigating the impact.

Science.gov (United States)

Brown, Hart S

2016-01-01

Historically, the unauthorised access and theft of information was a tactic used between countries as part of espionage campaigns, during times of conflict as well as for personal and criminal purposes. The consumers of the information were relatively isolated and specific. As information became stored and digitised in larger quantities in the 1980s the ability to access mass amounts of records at one time became possible. The expertise needed to remotely access and exfiltrate the data was not readily available and the number of markets to monetise the data was limited. Over the past ten years, shadow networks have been used by criminals to collaborate on hacking techniques, exchange hacking advice anonymously and commercialise data on the black market. The intersection of these networks along with the unintentional losses of information have resulted in 5,810 data breaches made public since 2005 (comprising some 847,807,830 records) and the velocity of these events is increasing. Organisations must be prepared for a potential breach event to maintain cyber resiliency. Proper management of a breach response can reduce response costs and can serve to mitigate potential reputational losses.

Removal of a synthetic organic chemical by PAC-UF systems. II: Model application.

Science.gov (United States)

Matsui, Y; Colas, F; Yuasa, A

2001-02-01

This paper describes several application potentials with a recently developed model for predicting the synthetic organic chemical (SOC) removal by powdered activated carbon (PAC) adsorption during ultrafiltration (UF) and discusses the removal mechanism. The model was successfully applied, without any modification, to dead-end mode operation as well as to cross-flow mode operation, validating the assumption of the internal diffusion control mechanism and the continuously-stirred-tank-reactor (CSTR) concept. Even when UF was operated in a cross-flow mode, PAC added was re-circulating in suspension for only a short time. Then, solute uptake took place mostly by PAC immobilized in membrane tubes not only for dead-end operation but also for cross-flow operation. Therefore, cross-flow operation did not have any advantage regarding the SOC mass transfer on PAC in UF loop over dead-end operation. The model simulation implied that pulse PAC addition at the beginning of filtration cycle resulted better SOC removal than continuous PAC addition. However, for the pulse PAC addition mode, the model predicted somewhat lower effluent SOC concentration than the observed values, and the benefit of pulse PAC application in terms of reducing SOC over its continuous dosage was not confirmed. Longer detention time of PAC dosed in a pulse than continuously dosed PAC could possibly further decrease internal diffusivity.

FFTF criteria for run to cladding breach experiments

International Nuclear Information System (INIS)

Van Keuren, J.C.; Heard, F.J.; Stepnewski, D.D.

1985-12-01

The review of experiments proposed for irradiation in FFTF resulted in the development of new criteria for run-to-cladding breach experiments. These criteria have allowed irradiation of aggressive experiments without compromising the safety bases for FFTF. This paper consisting of a set of narrated slides, discusses these criteria and related bases

50 CFR 38.9 - Breach of the peace.

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Breach of the peace. 38.9 Section 38.9... peace. No person on Midway Atoll National Wildlife Refuge will: (a) With intent to cause public..., gestures, or displays, or address abusive language to any person present; or create a hazardous or...

Spectroscopic properties of K5Li2UF10

International Nuclear Information System (INIS)

Karbowiak, M.; Gajek, Z.; Drozdzynski, J.

2005-01-01

A new uranium (III) fluoro-complex of the formula K 5 Li 2 UF 10 has been synthesised and characterised by X-ray powder diffraction and electronic absorption spectra measurements. The compound crystallises in the orthorhombic system, space group Pnma, with a = 20.723, b = 7.809, c = 6.932 A, V = 1121.89 A 3 , Z = 4 and is isostructural with its K 5 Li 2 NdF 10 and K 5 Li 2 LaF 10 analogous. The absorption spectrum of a polycrystalline sample of K 5 Li 2 UF 10 was recorded at 4.2 K in the 3500-45,000 cm -1 range and is discussed. The observed crystal-field levels were assigned and fitted to parameters of the simplified angular overlap model (AOM) and next to those of a semi-empirical Hamiltonian, which was representing the combined atomic and one-electron crystal-field interactions. The starting values of the AOM parameters were obtained from ab initio calculations. The analysis of the spectra enabled the assignment of 71 crystal-field levels of U 3+ with a relatively small r.m.s. deviation of 37 cm -1 . The total splitting of 714 cm -1 was calculated for the 4 I 9/2 ground multiplet

Spectroscopic properties of K 5Li 2UF 10

Science.gov (United States)

Karbowiak, M.; Gajek, Z.; Drożdżyński, J.

2005-04-01

A new uranium (III) fluoro-complex of the formula K 5Li 2UF 10 has been synthesised and characterised by X-ray powder diffraction and electronic absorption spectra measurements. The compound crystallises in the orthorhombic system, space group Pnma, with a = 20.723, b = 7.809, c = 6.932 Å, V = 1121.89 Å 3, Z = 4 and is isostructural with its K 5Li 2NdF 10 and K 5Li 2LaF 10 analogous. The absorption spectrum of a polycrystalline sample of K 5Li 2UF 10 was recorded at 4.2 K in the 3500-45,000 cm -1 range and is discussed. The observed crystal-field levels were assigned and fitted to parameters of the simplified angular overlap model (AOM) and next to those of a semi-empirical Hamiltonian, which was representing the combined atomic and one-electron crystal-field interactions. The starting values of the AOM parameters were obtained from ab initio calculations. The analysis of the spectra enabled the assignment of 71 crystal-field levels of U 3+ with a relatively small r.m.s. deviation of 37 cm -1. The total splitting of 714 cm -1 was calculated for the 4I 9/2 ground multiplet.

Direct and Indirect Effects of Psychological Contract Breach on Academicians’ Turnover Intention in Turkey

OpenAIRE

Buyukyilmaz, Ozan; Cakmak, Ahmet F.

2013-01-01

This study aims to investigate the assumed direct and indirect relationships between psychological contract breach and turnover intention through psychological contract violation and perceived organizational support. Data for the sample was collected from 570 academicians from a variety of universities in Turkey. Hierarchical regression analyses were conducted to test the hypotheses. The results show that psychological contract breach was positively related to turnover intention and psycholog...

Pinhole Breaches in Spent Fuel Containers: Some Modeling Considerations

International Nuclear Information System (INIS)

Casella, Andrew M.; Loyalka, Sudarsham K.; Hanson, Brady D.

2006-01-01

This paper replaces PNNL-SA-48024 and incorporates the ANS reviewer's comments, including the change in the title. Numerical methods to solve the equations for gas diffusion through very small breaches in spent fuel containers are presented and compared with previous literature results

Styrene process condensate treatment with a combination process of UF and NF for reuse.

Science.gov (United States)

Wang, Aijun; Liu, Guangmin; Huang, Jin; Wang, Lijuan; Li, Guangbin; Su, Xudong; Qi, Hong

2013-01-15

Aiming at reusing the SPC to save water resource and heat energy, a combination treatment process of UF/NF was applied to remove inorganic irons, suspended particles and little amount of organic contaminants in this article. To achieve the indexes of CODM≤5.00 mg L(-1), oil≤2.00 mg L(-1), conductivity≤10.00 μs cm(-1), pH of 6.0-8.0, the NF membrane process was adopted. It was necessary to employ a pretreatment process to reduce NF membrane fouling. Hence UF membrane as an efficient pretreatment unit was proposed to remove the inorganic particles, such as iron oxide catalyst, to meet the influent demands of NF. The effluent of UF, which was less than 0.02 mg L(-1) of total iron, went into a security filter and then was pumped into the NF process unit. High removal efficiencies of CODM, oil and conductivity were achieved by using NF process. The ABS grafting copolymerization experiment showed that the effluent of the combination process met the criteria of ABS production process, meanwhile the process could alleviate the environment pollution. It was shown that this combination process concept was feasible and successful in treating the SPC. Copyright © 2012 Elsevier B.V. All rights reserved.

Routes for breaching and protecting genetic privacy

OpenAIRE

Erlich, Yaniv; Narayanan, Arvind

2013-01-01

We are entering an era of ubiquitous genetic information for research, clinical care and personal curiosity. Sharing these datasets is vital for progress in biomedical research. However, one growing concern is the ability to protect the genetic privacy of the data originators. Here, we present an overview of genetic privacy breaching strategies. We outline the principles of each technique, point to the underlying assumptions, and assess its technological complexity and maturati...

Uniform deposition of uranium hexafluoride (UF6): Standardized mass deposits and controlled isotopic ratios using a thermal fluorination method.

Science.gov (United States)

McNamara, Bruce K; O'Hara, Matthew J; Casella, Andrew M; Carter, Jennifer C; Addleman, R Shane; MacFarlan, Paul J

2016-07-01

We report a convenient method for the generation of volatile uranium hexafluoride (UF6) from solid uranium oxides and other U compounds, followed by uniform deposition of low levels of UF6 onto sampling coupons. Under laminar flow conditions, UF6 is shown to interact with surfaces within a fixed reactor geometry to a highly predictable degree. We demonstrate the preparation of U deposits that range between approximately 0.01 and 500ngcm(-2). The data suggest the method can be extended to creating depositions at the sub-picogramcm(-2) level. The isotopic composition of the deposits can be customized by selection of the U source materials and we demonstrate a layering technique whereby two U solids, each with a different isotopic composition, are employed to form successive layers of UF6 on a surface. The result is an ultra-thin deposit that bears an isotopic signature that is a composite of the two U sources. The reported deposition method has direct application to the development of unique analytical standards for nuclear safeguards and forensics. Further, the method allows access to very low atomic or molecular coverages of surfaces. Copyright © 2016 Elsevier B.V. All rights reserved.

Potential detection systems for monitoring UF6 releases

International Nuclear Information System (INIS)

Beck, D.E.; Bostick, W.D.; Armstrong, D.P.; McNeely, J.R.; Stockdale, J.A.D.

1994-09-01

In the near future, the Nuclear Regulatory Commission (NRC) will begin to regulate the gaseous diffusion plants. Them is a concern that the smoke detectors currently used for uranium hexafluoride (UF 6 ) release detection will not meet NRC safety system requirements such as high reliability and rapid response. The NRC's position is that licensees should utilize state-of-the-art equipment such as hydrogen fluoride (HF) detectors that would provide more dependable detection of a UF 6 release. A survey of the literature and current vendor information was undertaken to define the state-of-the-art and commercial availability of HF (or other appropriate) detection systems. For the purpose of this report, classification of the available HF detection systems is made on the basis of detection principle (e.g., calorimetric, electrochemical, separational, or optical). Emphasis is also placed on whether the device is primarily sensitive to response from a point source (e.g., outleakage in the immediate vicinity of a specific set of components), or whether the device is potentially applicable to remote sensing over a larger area. Traditional HF point source monitoring typically uses gas sampling tubes or coated paper tapes with color developing indicator, portable and small area HF monitors are often based upon electrochemical or extractive/separational systems; and remote sensing by optical systems holds promise for indoor and outdoor large area monitoring (including plant boundary/ambient air monitoring)

Dam-breach analysis and flood-inundation mapping for Lakes Ellsworth and Lawtonka near Lawton, Oklahoma

Science.gov (United States)

Rendon, Samuel H.; Ashworth, Chad E.; Smith, S. Jerrod

2012-01-01

Dams provide beneficial functions such as flood control, recreation, and reliable water supplies, but they also entail risk: dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure or misoperation probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning the emergency response if a dam breach occurs. Accurate topographic data are vital for developing flood-inundation maps. This report presents results of a cooperative study by the city of Lawton, Oklahoma, and the U.S. Geological Survey (USGS) to model dam-breach scenarios at Lakes Ellsworth and Lawtonka near Lawton and to map the potential flood-inundation areas of such dam breaches. To assist the city of Lawton with completion of the emergency action plans for Lakes Ellsworth and Lawtonka Dams, the USGS collected light detection and ranging (lidar) data that were used to develop a high-resolution digital elevation model and a 1-foot contour elevation map for the flood plains downstream from Lakes Ellsworth and Lawtonka. This digital elevation model and field measurements, streamflow-gaging station data (USGS streamflow-gaging station 07311000, East Cache Creek near Walters, Okla.), and hydraulic values were used as inputs for the dynamic (unsteady-flow) model, Hydrologic Engineering Center's River Analysis System (HEC-RAS). The modeled flood elevations were exported to a geographic information system to produce flood-inundation maps. Water-surface profiles were developed for a 75-percent probable maximum

Observation and modeling of the evolution of an ephemeral storm-induced inlet: Pea Island Breach, North Carolina, USA

Science.gov (United States)

Velasquez Montoya, Liliana; Sciaudone, Elizabeth J.; Mitasova, Helena; Overton, Margery F.

2018-03-01

The Outer Banks of North Carolina is a wave-dominated barrier island system that has experienced the opening and closure of numerous inlets in the last four centuries. The most recent of those inlets formed after the breaching of Pea Island during Hurricane Irene in 2011. The Pea Island Breach experienced a rapid evolution including episodic curvature of the main channel, rotation of the ebb channel, shoaling, widening by Hurricane Sandy in 2012, and finally closing before the summer of 2013. Studying the life cycle of Pea Island Breach contributes to understanding the behavior of ephemeral inlets in breaching-prone regions. This topic has gained relevance due to rising sea levels, a phenomenon that increases the chances of ephemeral inlet formation during extreme events. This study explores the spatiotemporal effects of tides, waves, and storms on flow velocities and morphology of the breach by means of remotely sensed data, geospatial metrics, and a numerical model. The combined use of observations and results from modeling experiments allowed building a conceptual model to explain the life cycle of Pea Island Breach. Wave seasonality dominated the morphological evolution of the inlet by controlling the magnitude and direction of the longshore current that continuously built transient spits at both sides of the breach. Sensitivity analysis to external forcings indicates that ocean waves can modify water levels and velocities in the back barrier. Sound-side storm surge regulates overall growth rate, duration, and decay of peak water levels entering the inlet during extreme events.

24 CFR 982.453 - Owner breach of contract.

Science.gov (United States)

2010-04-01

...) If the owner has committed fraud, bribery or any other corrupt or criminal act in connection with any..., bribery or any other corrupt or criminal act in connection with the mortgage or loan. (5) If the owner has... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Owner breach of contract. 982.453...

Electroconvulsive therapy, hypertensive surge, blood-brain barrier breach, and amnesia

DEFF Research Database (Denmark)

Andrade, Chittaranjan; Bolwig, Tom G

2014-01-01

Preclinical and clinical evidence show that electroconvulsive therapy (ECT)-induced intraictal surge in blood pressure may result in a small, transient breach in the blood-brain barrier, leading to mild cerebral edema and a possible leach of noxious substances from blood into brain tissues...... convincing evidence of benefits. It is concluded that there is insufficient support, at present, for the hypothesis that the hypertensive surge during ECT and the resultant blood-brain barrier breach contribute meaningfully to ECT-induced cognitive deficits. Future research should address the subset....... These changes may impair neuronal functioning and contribute to the mechanisms underlying ECT-induced cognitive deficits. Some but not all clinical data on the subject suggest that blood pressure changes during ECT correlate with indices of cognitive impairment. In animal models, pharmacological manipulations...

Exploring the relationship between ADHD symptoms and prison breaches of discipline amongst youths in four Scottish prisons.

Science.gov (United States)

Gordon, V; Williams, D J; Donnelly, P D

2012-04-01

To explore the relationship between attention deficit hyperactivity disorder (ADHD) symptoms (inattention, hyperactivity and impulsivity) and violent and non-violent prison breaches of discipline in incarcerated male youths aged 18-21 years. A case-control study of 169 male youth offenders incarcerated in Scottish prisons and classified as 'symptomatic' or 'non-symptomatic' of inattentive and hyperactive/impulsive ADHD symptoms. ADHD symptoms were measured using the Conners' Adult ADHD Rating Scales-Self Report: Long Version, and prison breaches of discipline were gathered from the Scottish Prison Service's Prisoner Records System. Youths who were symptomatic of Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) ADHD total symptoms had a significantly higher number of prison breaches of discipline than those who were non-symptomatic. Youths who were symptomatic of DSM-IV hyperactive/impulsive symptoms had a significantly higher number of violent and non-violent prison breaches of discipline than those who were non-symptomatic. However, no such significant difference was found between youths who were symptomatic and non-symptomatic of DSM-IV inattentive symptoms. Young male offenders who are symptomatic of ADHD have a higher number of prison breaches of discipline. In particular, symptoms of hyperactivity/impulsivity are associated with breaches of both a violent and non-violent nature. Implications of such symptoms on rehabilitation and recidivism are discussed. Copyright © 2012 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Psychological contract types as moderator in the breach-violation and violation-burnout relationships.

Science.gov (United States)

Jamil, Amber; Raja, Usman; Darr, Wendy

2013-01-01

This research examined the relationships between perceived psychological contract breach, felt violation, and burnout in a sample (n = 361) of employees from various organizations in Pakistan. The moderating role of contract types in these relationships was also tested. Findings supported a positive association between perceived psychological contract breach and felt violation and both were positively related to burnout. Transactional and relational contracts moderated the felt violation-burnout relationship. Scores on relational contract type tended to be higher than for transactional contract type showing some contextual influence.

RESPEITO À CIDADANIA: PROVENDO ACESSIBILIDADE WEB NA UNIVERSIDADE FEDERAL DE SERGIPE (UFS

Directory of Open Access Journals (Sweden)

Quelita Araújo Diniz da Silva

2012-03-01

Full Text Available O acesso à informação facilitado pelas Tecnologias de Informação e Comunicação (TIC é um dos principais elementos da sociedade do conhecimento, sendo visto como possibilidade de inclusão social. Entretanto, alguns indivíduos possuem necessidades, permanentes ou temporárias, que os limitam no acesso às informações disponibilizadas, mantendo-os à periferia da sociedade. Este trabalho tem como objetivo discutir a acessibilidade na Web, discutindo os principais padrões, as diretrizes e técnicas para o projeto de webapps acessíveis. Como também, expor o conceito de tecnologias assistivas e como elas adequam às funcionalidades computacionais ao internauta com necessidades especiais auxiliando-o na navegação. Por fim, descrever um estudo de caso realizado no site da POSGRAP – UFS objetivando viabilizar à comunidade Sergipana à inclusão provendo acessibilidade aos produtos e serviços da UFS.

The regulations and the problems of their implementation in UF6 transport

International Nuclear Information System (INIS)

Devillers, C.; Grenier, M.; Ringot, C.; Warniez, P.

1988-12-01

UF 6 is currently transported in packagings which were developed in the sixties - standardized and used all over the world, these packagings perform their duty adequately. Nevertheless, the growing amounts of UF 6 and the changes in the regulations now raises the problem of compliance of these packagings with the latter. The problems which deserve special attention are: selection of the packaging type in terms of the origin and the enrichment, design of valve covers, behaviour at low temperatures, regulatory requirements in handling, tying down cleaning and unloading, allowable dose rate increase in case of minor mishaps, behaviour in fire, taking into account the toxicity, identification of special features required in the case of controlled moderation of fissile packages, transport conditions of empty packagings containing heels. In this paper are reviewed the results of this analysis, which is limited to the case of transport using cylinders of 48Y and 30B

Computer simulation of cooling properties of UF5 hot-clusters in argon

International Nuclear Information System (INIS)

Okamoto, Tsuyoshi; Ohno, Fubito

1999-01-01

Brownian collision-coalescence models have been proposed by many researchers to describe a cluster or a particle growth process. In these mathematical models, the effect of a cluster temperature on a sticking probability is not included, although the cluster temperature is one of the most important factors which determines the particle growth rate at the incipient stage of coagulation. A hot-cluster consisting of 30 UF 5 molecules is formed in a computer and is bombarded with argon atoms. Measuring a kinetic energy of argon atom scattered from the hot-cluster, the cluster temperature can be estimated by molecular dynamics simulations. It is concluded that the hot-cluster is rapidly cooled under the conditions of molecular laser isotope separation (MLIS) process, so that the cluster-argon system can reach its thermal equilibrium state. Therefore, in the analysis of the dynamics of clustering process, the temperature of UF 5 molecular cluster may be set equal to that of argon gas. (author)

Recycling Cellulase from Enzymatic Hydrolyzate of Laser-Pretreated Corn Stover by UF Membrane

Directory of Open Access Journals (Sweden)

Shuang-Qi Tian

2015-09-01

Full Text Available The ultrafiltration membrane reactor, utilizing a membrane module with a suitable molecular weight alleyway, retains the larger cellulase components. Smaller molecules, such as the fermentable reducing sugars and water, pass through the membrane. The purpose of this work was to investigate the capability of recycling cellulase in the UF membrane. PS30 hollow fiber membrane, an ultrafiltration method using internal pressure, was found to be an ideal membrane separation device, allowing re-use of the enzyme. A Box-Behnken experimental design (BBD established the following optimum pretreatment parameters: operation pressure at 1.73 bar, temperature at 36.38 °C, and a pH of 5.92. Under these conditions, the model predicted a membrane flux yield of 2.3174 L/(m2•h. The rejection rate of the UF membrane was over 95%.

BLT [Breach, Leach, and Transport]: A source term computer code for low-level waste shallow land burial

International Nuclear Information System (INIS)

Suen, C.J.; Sullivan, T.M.

1990-01-01

This paper discusses the development of a source term model for low-level waste shallow land burial facilities and separates the problem into four individual compartments. These are water flow, corrosion and subsequent breaching of containers, leaching of the waste forms, and solute transport. For the first and the last compartments, we adopted the existing codes, FEMWATER and FEMWASTE, respectively. We wrote two new modules for the other two compartments in the form of two separate Fortran subroutines -- BREACH and LEACH. They were incorporated into a modified version of the transport code FEMWASTE. The resultant code, which contains all three modules of container breaching, waste form leaching, and solute transport, was renamed BLT (for Breach, Leach, and Transport). This paper summarizes the overall program structure and logistics, and presents two examples from the results of verification and sensitivity tests. 6 refs., 7 figs., 1 tab

Emergency preparedness and response in case of a fire accident with (UF6) packages tracking Suez Canal

International Nuclear Information System (INIS)

Salama, M.

2004-01-01

Egypt has a unique problem - the Suez Canal. Radioactive cargo passing regularly through the canal carrying new and spent reactor fuel. Moreover there are also about 1000 metric tons of uranium hexaflouride (UF6) passing through the canal every year. In spite of all precautions taken in the transportation, accidents with packages containing (UF 6 ) and shipped through the Suez Canal, accidents may arise even though the probability is minimal. These accidents, may be accompanied by injuries or death of persons and damage to property. Due to the radiation and criticality hazards of (UF 6 ) and its high risk of chemical toxicity. The probability of a fire accident with a cargo carrying (UF 6 ) during its crossing the Suez Canal can cause serious chemical toxic and radiological hazards, particularly if the accident occurred close or near to one of the three densely populated cities (Port-Said, Ismailia, and Suez), which are located along the Suez Canal, west bank. The government of Egypt has elaborated a national radiological emergency plan inorder to face probable radiological accidents, which may be arised inside the country. Arrangements have been also elaborated for the medical care of any persons who, might be injured or contaminated, or who, have been exposed to severe radiation doses. The motivation of the present paper was undertaken to visualize a fire accident scenario occurring in industrial packages containing UF6 on board of a Cargo crossing the Suez Canal near Port-Said City. The accident scenario and emergency response actions taken during the different phases of the accident are going to be presented and discussed. The proposed emergency response actions taken to face the accident are going to be also presented. The work presented had revealed the importance of public awareness will be needed for populations located in densely populated areas along Suez Canal bank inorder to react timely and effectively to avoid the toxic and radiological hazards

Psychological contract breach and outcomes: Combining meta-analysis and structural equation models.

Science.gov (United States)

Topa Cantisano, Gabriela; Morales Domínguez, J Francisco; Depolo, Marco

2008-08-01

In this study, meta-analytic procedures were used to examine the relationships between psychological contract perceived breach and certain outcome variables, such as organizational commitment, job satisfaction and organizational citizenship behaviours (OCB). Our review of the literature generated 41 independent samples in which perceived breach was used as a predictor of these personal and organizational outcomes. A medium effect size (ES) for desirable outcomes (job satisfaction, organizational commitment, organizational trust, OCB and performance) was obtained (r=-.35). For undesirable outcomes (neglect in role duties and intention to leave), ES were also medium (r=.31). When comparing attitudinal (job satisfaction, organizational commitment, organizational trust) and behavioural outcomes (OCB, neglect in role duties and performance), a stronger ES was found for attitudinal (r=-.24) than for behavioural outcomes (r=-.11). Potential moderator variables were examined, and it was found that they explained only a percentage of variability of primary studies. Structural equation analysis of the pooled meta-analytical correlation matrix indicated that the relationships of perceived breach with satisfaction, OCB, intention to leave and performance are fully mediated by organizational trust and commitment. Results are discussed in order to suggest theoretical and empirical implications.

ECONOMIC AND LEGAL ASPECTS OF THE PLANNED DAMAGES ACTIONS FOR THE BREACHES OF EC ANTITRUST LAW

Directory of Open Access Journals (Sweden)

Elena Isac

2010-09-01

Full Text Available This paper investigates the planned damages actions for breaches of EC antitrust law in order to assess their impact on consumer welfare. It first examines the current legal situation and concurs that the European Union needs to regulate damages actions for breaches of EC antitrust law so that a higher number of consumers could be compensated for their losses. This paper then discusses the main legal provisions proposed by the Commission in the Green and in the White paper on damages actions for breaches of EC antitrust law. The analysis of these proposed legal provisions is done using arguments specific to the economic analysis of law. It is demonstrated that most of these proposed legal provisions will enhance consumer welfare but that there are also proposed legal provisions which will damage consumer welfare. The paper concludes that the planned damages actions for breaches of the EC law will be an improvement compared to the current situation. However, the Commission should amend some of the proposed legal provisions in order to help consumers further.

Fracture mechanics performance of UF6 containers

International Nuclear Information System (INIS)

Gonzalez, M.E.; Iorio, A.F.; Crespi, J.C.

1993-01-01

The main purpose of this work was to determine the fracture mechanics performance of UF 6 transport cylinders type ANSI N14.1.30B, which was made from ASTM A 516 Grade 70 steel. It was assumed an internal surface axial crack subjected to stresses due to service, proof and transport accident loads. The KUMAR-GERMAN-SHIH elastoplastic methodology gave adequate results for crack depth estimation. The results validate the leak-before-break criteria for service and proof conditions but not for accident ones. In the last case a non-destructive examination must be done in order to assure the absence of defects larger than one third of the cylinder wall thickness. (Author)

Calculational criticality analyses of 10- and 20-MW UF6 freezer/sublimer vessels

International Nuclear Information System (INIS)

Jordan, W.C.

1993-02-01

Calculational criticality analyses have been performed for 10- and 20-MW UF 6 freezer/sublimer vessels. The freezer/sublimers have been analyzed over a range of conditions that encompass normal operation and abnormal conditions. The effects of HF moderation of the UF 6 in each vessel have been considered for uranium enriched between 2 and 5 wt % 235 U. The results indicate that the nuclearly safe enrichments originally established for the operation of a 10-MW freezer/sublimer, based on a hydrogen-to-uranium moderation ratio of 0.33, are acceptable. If strict moderation control can be demonstrated for hydrogen-to-uranium moderation ratios that are less than 0.33, then the enrichment limits for the 10-MW freezer/sublimer may be increased slightly. The calculations performed also allow safe enrichment limits to be established for a 20-NM freezer/sublimer under moderation control

Use of a radioactive substance, the depleted uranium, for the fabrication of enamels and usual things and jewels decoration

International Nuclear Information System (INIS)

1999-01-01

This open letter to the ministers and State Secretaries of the public health, the environment and the consumers protection, deals with a complaint against X, lodged by the CRII-RAD. This complaint concerns the use of depleted uranium for the fabrication of enamels and the decoration of usual things and jewels. This utilization constitutes a breach of the decree 66-450, which forbids since 1966 the addition of radioactive substances in food, cosmetic and domestic products. The letter takes into account the hazards for the workers and the consumers, the uranium powder origin and discusses the guaranties forecast under the legislation eye. (A.L.B.)

Quality assurance in the transport of UF{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Ravenscroft, N.L. [Edlow International Company, Washington, DC (United States)

1991-12-31

Edlow International`s primary business is the international transportation of radioactive materials. Therefore, Edlow has the responsibility to ensure that shipments are performed in compliance with regulatory requirements. In this regard, Edlow maintains a Quality Assurance (QA) Program. A major part of this Program is the establishment and use of QA Procedures. This paper addresses QA procedural requirements and how they are applied to a routine international shipment of low enriched UF{sub 6}. Only the major requirements for scheduling shipments will be addressed.

Breaching barriers to collaboration in public spaces

DEFF Research Database (Denmark)

Heinemann, Trine; Mitchell, Robb

2014-01-01

Technology provoking disparate individuals to collaborate or share experiences in the public space faces a difficult barrier, namely the ordinary social order of urban places. We employed the notion of the breaching experiment to explore how this barrier might be overcome. We analyse responses...... of life in public spaces. Arising from this, we argue for the importance of qualities such as availability, facilitation, perspicuous settings, and perspicuous participants to encourage and support co-located strangers to collaborate and share experiences....

Release of UF6 from a ruptured model 48Y cylinder at Sequoyah Fuels Corporation Facility: lessons-learned report

International Nuclear Information System (INIS)

1986-08-01

The uranium hexafluoride (UF 6 ) release of January 4, 1986, at the Sequoyah Fuels Corporation facility has been reviewed by a NRC Lessons-Learned Group. A Model 48Y cylinder containing UF 6 ruptured upon being heated after it was grossly overfilled. The UF 6 released upon rupture of the cylinder reacted with airborne moisture to produce hydrofluoric acid (HF) and uranyl fluoride (UO 2 F 2 ). One individual died from exposure to airborne HF and several others were injured. There were no significant immediate effects from exposure to uranyl fluoride. This supplement report contains NRC's response to the recommendations made in NUREG-1198 by the Lessons Learned Group. In developing a response to each of the recommendations, the staff considered actions that should be taken: (1) for the restart of the Sequoyah Fuels Facility; (2) to make near-term improvement; and (3) to improve the regulatory framework

CONTAINMENT EVALUATION OF BREACHED AL-SNF FOR CASK TRANSPORT

International Nuclear Information System (INIS)

Vinson, D. W.; Sindelar, R. L.; Iyer, N. C.

2005-01-01

Aluminum-based spent nuclear fuel (Al-SNF) from foreign and domestic research reactors (FRR/DRR) is being shipped to the Savannah River Site. To enter the U.S., the cask with loaded fuel must be certified to comply with the requirements in the Title 10 of the U.S. Code of Federal Regulations, Part 71. The requirements include demonstration of containment of the cask with its contents under normal and accident conditions. Al-SNF is subject to corrosion degradation in water storage, and many of the fuel assemblies are ''failed'' or have through-clad damage. A methodology has been developed with technical bases to show that Al-SNF with cladding breaches can be directly transported in standard casks and maintained within the allowable release rates. The approach to evaluate the limiting allowable leakage rate, L R , for a cask with breached Al-SNF for comparison to its test leakage rate could be extended to other nuclear material systems. The approach for containment analysis of Al-SNF follows calculations for commercial spent fuel as provided in NUREG/CR-6487 that adopts ANSI N14.5 as a methodology for containment analysis. The material-specific features and characteristics of damaged Al-SNF (fuel materials, fabrication techniques, microstructure, radionuclide inventory, and vapor corrosion rates) that were derived from literature sources and/or developed in laboratory testing are applied to generate the four containment source terms that yield four separate cask cavity activity densities; namely, those from fines; gaseous fission product species; volatile fission product species; and fuel assembly crud. The activity values, A 2 , are developed per the guidance of 10CFR71. The analysis is performed parametrically to evaluate maximum number of breached assemblies and exposed fuel area for a proposed shipment in a cask with a test leakage rate

Rupture of Model 48Y UF6 cylinder and release of uranium hexafluoride, Sequoyah Fuels Facility, Gore, Oklahoma, January 4, 1986. Volume 1

International Nuclear Information System (INIS)

1986-02-01

At 11:30 a.m. on January 4, 1986, a Model 48Y UF 6 cylinder filled with uranium hexafluoride (UF 6 ) ruptured while it was being heated in a steam chest at the Sequoyah Fuels Conversion Facility near Gore, Oklahoma. One worker died because he inhaled hydrogen fluoride fumes, a reaction product of UF 6 and airborne moisture. Several other workers were injured by the fumes, but none seriously. Much of the facility complex and some offsite areas to the south were contaminated with hydrogen fluoride and a second reaction product, uranyl fluoride. The interval of release was approximately 40 minutes. The cylinder, which had been overfilled, ruptured while it was being heated because of the expansion of UF 6 as it changed from the solid to the liquid phase. The maximum safe capacity for the cylinder is 27,560 pounds of product. Evidence indicates that it was filled with an amount exceeding this limit. 18 figs

Thermodynamic properties of a high pressure subcritical UF6He gas volume (irradiated by an external source)

International Nuclear Information System (INIS)

Sterritt, D.E.; Lalos, G.T.; Schneider, R.T.

1976-12-01

A computer simulation study concerning a compressed fissioning UF 6 gas is presented. The compression is to be achieved by a ballistic piston compressor. Data on UF 6 obtained with this compressor were incorporated in the simulation study. As a neutron source to create the fission events in the compressed gas, a fast burst reactor was considered. The conclusion is that it takes a neutron flux in excess of 10 15 n/cm 2 -s to produce measurable increases in pressure and temperature, while a flux in excess of 10 19 n/cm 2 -s would probably damage the compressor

Coastal bathymetry data collected in May 2015 from Fire Island, New York—Wilderness breach and shoreface

Science.gov (United States)

Nelson, Timothy R.; Miselis, Jennifer L.; Hapke, Cheryl J.; Brenner, Owen T.; Henderson, Rachel E.; Reynolds, Billy J.; Wilson, Kathleen E.

2017-05-12

Scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center in St. Petersburg, Florida, conducted a bathymetric survey of Fire Island from May 6-20, 2015. The USGS is involved in a post-Hurricane Sandy effort to map and monitor the morphologic evolution of the wilderness breach as a part of the Hurricane Sandy Supplemental Project GS2-2B. During this study, bathymetry data were collected with single-beam echo sounders and Global Positioning Systems, which were mounted to personal watercraft, along the Fire Island shoreface and within the wilderness breach. Additional bathymetry and elevation data were collected using backpack Global Positioning Systems on flood shoals and in shallow channels within the wilderness breach.

Breach of duty: Power of shareholders to ratify directors fraudulent dealings

Directory of Open Access Journals (Sweden)

Anthony O. Nwafor

2014-07-01

Full Text Available Company directors owe duty of loyalty to the company which prohibits them from fraudulent dealings in the course of conducting the affairs of the company. Although the shareholders could, in the exercise of their voting powers, grant relieves to the directors from liabilities arising from a breach of duty that amounts to fraud, the extent and capacity in which the shareholders could exercise such powers is confounded by the elusive attempts by the courts in defining fraud. The paper argues that without a definite meaning ascribed to fraud, the power and capacity in which the shareholders could ratify a breach of duty arising from self-dealing and expropriation of corporate opportunities by directors cannot be predetermined, but that each case would be based on the peculiarities of its own facts.

Hydraulic breakage of tanks for the transport of uranium hexafluoride (UF6)

International Nuclear Information System (INIS)

Biaggio, A.L.; Lee Gonzales, H.M.; Lopez Vietri, J.R.; Novo, R.G.

1987-01-01

To begin with, the tank models that are proposed by the international norms for the transport and storage of hexafluoride of uranium (UF 6 ) are briefly described. The operations related to the transport in its different forms are also described, particularly those that can produce the hydraulic breakage of tanks during its course or in later stages, when incorrectly performed. With reference to those operations, the most important physicochemical properties of UF 6 as for safety are analyzed. A quantitative evaluation of the deviations of parameters that are controlled during the heating of tanks, comparing them with the normative nominal values, is performed. Adopting some simplifying hypothesis, a general study, applicable to all tank models proposed by norms, is carried out to determine the temperature at which the hydraulic breakage takes place when they are heated in closed-valve conditions. A curve is obtained by plotting the hydraulic breakage temperature against the filling degree. To conclude, the values obtained are compared with the results of other theoretical studies on this subject. (Author)

Evaluation of a RF-Based Approach for Tracking UF6 Cylinders at a Uranium Enrichment Plant

International Nuclear Information System (INIS)

Pickett, Chris A; Younkin, James R; Kovacic, Donald N; Laughter, Mark D; Hines, Jairus B; Boyer, Brian Martinez

2008-01-01

Approved industry-standard cylinders are used globally to handle and store uranium hexafluoride (UF 6 ) feed, product, tails, and samples at uranium enrichment plants. The International Atomic Energy Agency (IAEA) relies on time-consuming physical inspections to verify operator declarations and detect possible diversion of UF 6 . Development of a reliable, automated, and tamper-resistant system for near real-time tracking and monitoring UF 6 cylinders (as they move within an enrichment facility) would greatly improve the inspector function. This type of system can reduce the risk of false or misreported cylinder tare weights, diversion of nuclear material, concealment of excess production, utilization of undeclared cylinders, and misrepresentation of the cylinders contents. This paper will describe a proof-of-concept approach that was designed to evaluate the feasibility of using radio frequency (RF)-based technologies to track individual UF 6 cylinders throughout a portion of their life cycle, and thus demonstrate the potential for improved domestic accountability of materials, and a more effective and efficient method for application of site-level IAEA safeguards. The evaluation system incorporates RF-based identification devices (RFID) which provide a foundation for establishing a reliable, automated, and near real-time tracking system that can be set up to utilize site-specific, rules-based detection algorithms. This paper will report results from a proof-of-concept demonstration at a real enrichment facility that is specifically designed to evaluate both the feasibility of using RF to track cylinders and the durability of the RF equipment to survive the rigors of operational processing and handling. The paper also discusses methods for securely attaching RF devices and describes how the technology can effectively be layered with other safeguard systems and approaches to build a robust system for detecting cylinder diversion. Additionally, concepts for off

Emergency preparedness and response in case of a fire accident with (UF{sub 6}) packages tracking Suez Canal

Energy Technology Data Exchange (ETDEWEB)

Salama, M. [National Center for Nuclear Safety and Radiation Control (NCNSRC), Nasr City, Cairo (Egypt)

2004-07-01

Egypt has a unique problem - the Suez Canal. Radioactive cargo passing regularly through the canal carrying new and spent reactor fuel. Moreover there are also about 1000 metric tons of uranium hexaflouride (UF6) passing through the canal every year. In spite of all precautions taken in the transportation, accidents with packages containing (UF{sub 6}) and shipped through the Suez Canal, accidents may arise even though the probability is minimal. These accidents, may be accompanied by injuries or death of persons and damage to property. Due to the radiation and criticality hazards of (UF{sub 6}) and its high risk of chemical toxicity. The probability of a fire accident with a cargo carrying (UF{sub 6}) during its crossing the Suez Canal can cause serious chemical toxic and radiological hazards, particularly if the accident occurred close or near to one of the three densely populated cities (Port-Said, Ismailia, and Suez), which are located along the Suez Canal, west bank. The government of Egypt has elaborated a national radiological emergency plan inorder to face probable radiological accidents, which may be arised inside the country. Arrangements have been also elaborated for the medical care of any persons who, might be injured or contaminated, or who, have been exposed to severe radiation doses. The motivation of the present paper was undertaken to visualize a fire accident scenario occurring in industrial packages containing UF6 on board of a Cargo crossing the Suez Canal near Port-Said City. The accident scenario and emergency response actions taken during the different phases of the accident are going to be presented and discussed. The proposed emergency response actions taken to face the accident are going to be also presented. The work presented had revealed the importance of public awareness will be needed for populations located in densely populated areas along Suez Canal bank inorder to react timely and effectively to avoid the toxic and radiological

Motive Matters! An exploration of the notion ‘deliberate breach of contract’ and its consequences for the application of remedies

OpenAIRE

Kogelenberg, Martijn

2012-01-01

textabstractThis thesis explores the notion of deliberate breach of contract and its potential remedial consequences. In the major jurisdictions in Europe and in the United States the notion of deliberate breach of contract is generally not coherently and officially defined and acknowledged as an independent legal phenomenon. The ultimate added value of this thesis intends to be a first coherent comparative research on deliberate breach of contract and its potential consequences for the core ...

Consequences of and remedies for breach of natural gas contracts

International Nuclear Information System (INIS)

Gretener, N. M.; Evans, A.; Callihoo, M.

1999-01-01

A common clause in a gas purchase contract is one that provides for specific damages for the non-performance of an obligation. As a rule, damages will be calculated based on the loss in the value of the bargain plus those losses foreseeably caused by the breach of contract. the rationale being to put the non-breaching party in as good a position as it would have been had the contract been performed. This paper examines the complex issues involved assessing and measuring damages, the concept of injunctive relief in circumstances where damages will be inadequate or insufficient to prevent injustice, the doctrine of mitigation, the extent of the right of set-off between different contracts, and the impact of bankruptcy and insolvency laws on the exercise of remedies. Four case histories are presented to illustrate the Courts' treatment of gas purchase contracts in the context of bankruptcies and /or insolvencies. 36 refs

Consequences of and remedies for breach of natural gas contracts

Energy Technology Data Exchange (ETDEWEB)

Gretener, N. M.; Evans, A.; Callihoo, M. [Bennett Jones Law Group, Calgary, AB (Canada)

1999-07-01

A common clause in a gas purchase contract is one that provides for specific damages for the non-performance of an obligation. As a rule, damages will be calculated based on the loss in the value of the bargain plus those losses foreseeably caused by the breach of contract. the rationale being to put the non-breaching party in as good a position as it would have been had the contract been performed. This paper examines the complex issues involved assessing and measuring damages, the concept of injunctive relief in circumstances where damages will be inadequate or insufficient to prevent injustice, the doctrine of mitigation, the extent of the right of set-off between different contracts, and the impact of bankruptcy and insolvency laws on the exercise of remedies. Four case histories are presented to illustrate the Courts' treatment of gas purchase contracts in the context of bankruptcies and /or insolvencies. 36 refs.

Fate of antibiotics in activated sludge followed by ultrafiltration (CAS-UF) and in a membrane bioreactor (MBR).

Science.gov (United States)

Sahar, Eyal; Messalem, Rami; Cikurel, Haim; Aharoni, Avi; Brenner, Asher; Godehardt, Manuel; Jekel, Martin; Ernst, Mathias

2011-10-15

The fates of several macrolide, sulphonamide, and trimethoprim antibiotics contained in the raw sewage of the Tel-Aviv wastewater treatment plant (WWTP) were investigated after the sewage was treated using either a full-scale conventional activated sludge (CAS) system coupled with a subsequent ultrafiltration (UF) step or a pilot membrane bioreactor (MBR) system. Antibiotics removal in the MBR system, once it achieved stable operation, was 15-42% higher than that of the CAS system. This advantage was reduced to a maximum of 20% when a UF was added to the CAS. It was hypothesized that the contribution of membrane separation (in both systems) to antibiotics removal was due either to sorption to biomass (rather than improvement in biodegradation) or to enmeshment in the membrane biofilm (since UF membrane pores are significantly larger than the contaminant molecules). Batch experiments with MBR biomass showed a markedly high potential for sorption of the tested antibiotics onto the biomass. Moreover, methanol extraction of MBR biomass released significant amounts of sorbed antibiotics. This finding implies that more attention must be devoted to the management of excess sludge. Copyright © 2011 Elsevier Ltd. All rights reserved.

Making Sociology Relevant: The Assignment and Application of Breaching Experiments

Science.gov (United States)

Rafalovich, Adam

2006-01-01

Breaching experiments involve the conscious exhibition of "unexpected" behavior, an observation of the types of social reactions such behavioral violations engender, and an analysis of the social structure that makes these social reactions possible. The conscious violation of norms can be highly fruitful for sociology students, providing insights…

Work engagement, psychological contract breach and job satisfaction

OpenAIRE

Rayton, Bruce A.; Yalabik, Zeynep Y.

2014-01-01

This study extends both Social Exchange Theory and the Job Demands-Resources model by examining the link between psychological contract breach (PCB) and work engagement, and by integrating job satisfaction into this exchange relationship. We argue that PCB reflects employees' feelings of resource loss, and that these feelings impact work engagement through their impact on job satisfaction. Levels of employee work engagement can therefore be viewed as reciprocation for the exchange content pro...

A probabilistic safety analysis of UF{sub 6} handling at the Portsmouth Gaseous Diffusion Plant

Energy Technology Data Exchange (ETDEWEB)

Boyd, G.J.; Lewis, S.R.; Summitt, R.L. [Safety and Reliability Optimization Services (SAROS), Inc., Knoxville, TN (United States)

1991-12-31

A probabilistic safety study of UF{sub 6} handling activities at the Portsmouth Gaseous Diffusion Plant has recently been completed. The analysis provides a unique perspective on the safety of UF{sub 6} handling activities. The estimated release frequencies provide an understanding of current risks, and the examination of individual contributors yields a ranking of important plant features and operations. Aside from the probabilistic results, however, there is an even more important benefit derived from a systematic modeling of all operations. The integrated approach employed in the analysis allows the interrelationships among the equipment and the required operations to be explored in depth. This paper summarizes the methods used in the study and provides an overview of some of the technical insights that were obtained. Specific areas of possible improvement in operations are described.

Establishing breach of the duty of care in the tort of negligence.

Science.gov (United States)

Tingle, John

This article, the third in a series on clinical negligence, looks at the law surrounding breach of the duty of care in negligence. It shows some of the principles that judges and lawyers use in order to decide whether a person has broken his/her duty of care in the tort of negligence. It will be seen that the principles are contained in decided court cases, some of which are quite old but are still relevant today. The focus of this article is on the rule that courts, in deciding the issue of a breach of duty of care, would judge the defendant's conduct by the standard of what the hypothetical, 'reasonable person' would have done in the circumstances of the case.

Psychological contract breach in the anticipatory stage of change : Employee responses and the moderating role of supervisory informational justice

NARCIS (Netherlands)

De Ruiter, M.; Schaveling, J.; Schalk, R.; Gelder, van D.

2016-01-01

This study examined the impact of two types of psychological contract breach (organizational policies and social atmosphere breach) on resistance to change and engagement in the anticipatory phase of change and assessed whether supervisory informational justice mitigated the negative effects of

Psychological contract breach in the anticipatory stage of change : Employee responses and the moderating role of supervisory informational justice

NARCIS (Netherlands)

de Ruiter, M.; Schalk, R.; Schaveling, Jaap; van Gelder, Daniel

This study examined the impact of two types of psychological contract breach (organizational policies and social atmosphere breach) on resistance to change and engagement in the anticipatory phase of change and assessed whether supervisory informational justice mitigated the negative effects of

Treatment of poultry slaughterhouse wastewater using a static granular bed reactor (SGBR) coupled with ultrafiltration (UF) membrane system.

Science.gov (United States)

Basitere, M; Rinquest, Z; Njoya, M; Sheldon, M S; Ntwampe, S K O

2017-07-01

The South African poultry industry has grown exponentially in recent years due to an increased demand for their products. As a result, poultry plants consume large volumes of high quality water to ensure that hygienically safe poultry products are produced. Furthermore, poultry industries generate high strength wastewater, which can be treated successfully at low cost using anaerobic digesters. In this study, the performance of a bench-scale mesophilic static granular bed reactor (SGBR) containing fully anaerobic granules coupled with an ultrafiltration (UF) membrane system, as a post-treatment system, was investigated. The poultry slaughterhouse wastewater was characterized by a chemical oxygen demand (COD) range between 1,223 and 9,695mg/L, average biological oxygen demand of 2,375mg/L and average fats, oil and grease (FOG) of 554mg/L. The SGBR anaerobic reactor was operated for 9 weeks at different hydraulic retention times (HRTs), i.e. 55 and 40 h, with an average organic loading rate (OLR) of 1.01 and 3.14g COD/L.day. The SGBR results showed an average COD, total suspended solids (TSS) and FOG removal of 93%, 95% and 90% respectively, for both OLR. The UF post-treatment results showed an average of COD, TSS and FOG removal of 64%, 88% and 48%, respectively. The overall COD, TSS and FOG removal of the system (SGBR and UF membrane) was 98%, 99.8%, and 92.4%, respectively. The results of the combined SGBR reactor coupled with the UF membrane showed a potential to ensure environmentally friendly treatment of poultry slaughterhouse wastewater.

Routes for breaching and protecting genetic privacy.

Science.gov (United States)

Erlich, Yaniv; Narayanan, Arvind

2014-06-01

We are entering an era of ubiquitous genetic information for research, clinical care and personal curiosity. Sharing these data sets is vital for progress in biomedical research. However, a growing concern is the ability to protect the genetic privacy of the data originators. Here, we present an overview of genetic privacy breaching strategies. We outline the principles of each technique, indicate the underlying assumptions, and assess their technological complexity and maturation. We then review potential mitigation methods for privacy-preserving dissemination of sensitive data and highlight different cases that are relevant to genetic applications.

Plugging Effects on Depressurization Time in Dry Storage Containers with Pinhole Breaches

International Nuclear Information System (INIS)

Casella, Andrew M.; LOYALKA, SUDARSHAN K.; Hanson, Brady D.

2006-01-01

As continuation on previous work, we now examine the effect that aerosol deposition may have on plugging pinhole breaches in spent fuel containers. A model is developed considering only diffusive settling

LX-17 and ufTATB Data for Corner-Turning, Failure and Detonation

Energy Technology Data Exchange (ETDEWEB)

Souers, P C; Lauderbach, L; Garza, R; Vitello, P; Hare, D E

2010-02-03

Data is presented for the size (diameter) effect for ambient and cold confined LX-17, unconfined ambient LX-17, and confined ambient ultrafine TATB. Ambient, cold and hot double cylinder corner-turning data for LX-17, PBX 9502 and ufTATB is presented. Transverse air gap crossing in ambient LX-17 is studied with time delays given for detonations that cross.

SECURITY BREACH IN TRADING SYSTEM-COUNTERMEASURE USING IPTRACEBACK

OpenAIRE

M. P. Rajakumar; V. Shanthi

2014-01-01

Recently, economic scenario is often facing security breach that has heavy impact on the financial soundness of a company particularly, stock prices on firms. The utmost consequence being the whole business comes to a standstill. From the estimates attributed by the financial sector, it has been inferred that the loss incurred on virus and worms attack is said to have the greatest impact that hampers the prosperity of a business entity. Thus, security strategies attempt on revolving around th...

Economical and neutronic performance of HYLIFE-II with mixture of 90% flibe + 10% UF4 (or ThF4)

International Nuclear Information System (INIS)

Uenalan, Sebahattin

2004-01-01

This work investigated the neutronics behavior and the economics of the HYLIFE-II reactor with ThF 4 and UF 4 , which produces an electrical power of 1 GW from the fusion power of 2.857 GW during the operation period of 30 years. The use of ThF 4 and UF 4 is realized by a mixture zone consisted of 90% flibe (Li 2 BeF 4 ) and 10% fuel, instead of 100% flibe coolant. The mixture compositions are selected as 90% flibe + 10% UF 4 , 90% flibe + 10% ThF 4 and 90% flibe + 5% UF 4 + 5% ThF 4 . The capacity factor of the reactor is 0.75. The mixtures, with zone thickness of 65 cm were circulated with periods of 20.22, 19.89 and 20.11 s during the operation period of 30 years, respectively. In addition, for flibe + UF 4 , power stabilization by means of plutonium separation from the mixture was applied. The use of fuel materials in the HYLIFE-II reactor resulted in high energy production, sufficient tritium breeding, significant fissile fuel breeding and low radiation damage in the first wall. The average values of tritium breeding ratio over 30 years are between 1.08 and 1.12, higher than 1.0 indicating sufficient tritium breeding. Generally, the mixtures with ThF 4 show better performance than the mixture with UF 4 in terms of more energy production and significant fissile fuel breeding. The neutronic performance of the reactor increases with the operational period. However, the stabilization process performed after operation for 6 years causes all neutronic values to remain nearly constant during the followed operation time. At the 6th year of operation, the power production, which is ∼1540 MW(electric) at startup, reached the electrical power of 2 GW for flibe + UF 4 . The power production without the separation process reached ∼3500 MW(electric) for the mixtures with ThF 4 and ∼3000 MW(electric) for the mixture with UF 4 . At the end of the operation period, helium production values in the first wall, made of Hastelloy, are calculated as 590 ppm without the

Quick Look Report for Chemical Reactivity Modeling of Various Multi-Canister Overpack Breaches

International Nuclear Information System (INIS)

Bratton, Robert Lawrence

2002-01-01

This report makes observations or shows trends in the response and does not specifically provide conclusions or predict the onset of bulk uranium oxidation safety margins based on hole size. Comprehensive analysis will be provided in the future. The report should animate discussions about the results and what should be analyzed further in the final analysis. This report intends only to show the response of the breached multi-canister overpack (MCO) as a function of event time using the GOTH( ) SNF computer code. The response will be limited to physical quantities available on the exterior of the MCO. The GOTH( ) SNF model is approximate, because not all physical phenomenon was included in the model. Error estimates in the response are not possible at this time, because errors in the actual physical data are not known. Sensitivities in the results from variations in the physical data have not been pursued at this time, either. This effort was undertaken by the National Spent Nuclear Fuel Program to evaluate potential chemical reactivity issues of a degraded uranium metal spent nuclear fuel using the MCO fully loaded with Mark IV N-reactor fuel as the evaluation model. This configuration is proposed for handling in the Yucca Mountain Project (YMP) surface facility. Hanford is loading N-reactor fuel elements into the MCO for interim storage at the Hanford site with permanent disposal proposed at YMP. A portion of the N-reactor fuel inventory has suffered corrosion, exposing the uranium metal under the zircaloy cladding. Because of the sealed MCO, the local radiation field, and decay heat of the fuel, hydrogen production cannot be ruled out from the metal hydrates on the surface of the zircaloy cladding and exposed fuel. Because of the much greater surface area, the oxyhydroxide composition, and water of hydration in the uranium metal corrosion product, the corrosion product will be a significant water source that may equal the absorbed water on the zircaloy cladding

In-line coagulation prior to UF of treated domestic wastewater - foulants removal, fouling control and phosphorus removal

KAUST Repository

Zheng, Xing; Plume, Stephan; Ernst, Mathias; Croue, Jean-Philippe; Jekel, Martin R.

2012-01-01

The present work investigated fouling control and phosphorus removal by applying in-line coagulation prior to ultrafiltration (UF) of treated domestic wastewater. Experiments were conducted in both lab- and pilot-scale under close to neutral pH condition. Lab-scale foulant removal tests showed that increasing the dosage of FeCl3, AlCl3 and polymeric aluminum chloride (PACl) can improve biopolymer removal. Specifically, PACl reduced preferentially the proteinaceous fraction of biopolymer while the other two coagulants showed no significant preference. The filterability of water samples was improved after coagulation, which is contributed to biopolymer removal and the formation of larger particles. Pilot UF experiments demonstrated that in-line coagulation improved the performance of UF to a large extent. Within 0.037-0.148mmol Me3+/L dosage range, adding more FeCl3 and AlCl3 slowed down the development of trans-membrane pressure (TMP) correspondingly, while changing PACl dosage showed little effect on the variation of TMP increase rate. Further investigations indicated that PACl related precipitates contributed to more irreversible fouling than that which the monomeric coagulants made. Fouling control is thus considered as a co-effect determined by foulant removal efficiency, fouling layer structure and the adherence of hydrolysis products/precipitates onto the membrane. With respect to phosphorus removal, dosing FeCl3 and AlCl3 achieved higher removal efficiency than using PACl. Based on lab- and pilot-scale results, dosing FeCl3 and AlCl3 at a relative dosage of over 2.5mol Me3+ per mol total phosphorus (TP) in feedwater is necessarily required to keep the TP concentration under 50μg/L in UF permeate. © 2012 Elsevier B.V.

In-line coagulation prior to UF of treated domestic wastewater - foulants removal, fouling control and phosphorus removal

KAUST Repository

Zheng, Xing

2012-06-01

The present work investigated fouling control and phosphorus removal by applying in-line coagulation prior to ultrafiltration (UF) of treated domestic wastewater. Experiments were conducted in both lab- and pilot-scale under close to neutral pH condition. Lab-scale foulant removal tests showed that increasing the dosage of FeCl3, AlCl3 and polymeric aluminum chloride (PACl) can improve biopolymer removal. Specifically, PACl reduced preferentially the proteinaceous fraction of biopolymer while the other two coagulants showed no significant preference. The filterability of water samples was improved after coagulation, which is contributed to biopolymer removal and the formation of larger particles. Pilot UF experiments demonstrated that in-line coagulation improved the performance of UF to a large extent. Within 0.037-0.148mmol Me3+/L dosage range, adding more FeCl3 and AlCl3 slowed down the development of trans-membrane pressure (TMP) correspondingly, while changing PACl dosage showed little effect on the variation of TMP increase rate. Further investigations indicated that PACl related precipitates contributed to more irreversible fouling than that which the monomeric coagulants made. Fouling control is thus considered as a co-effect determined by foulant removal efficiency, fouling layer structure and the adherence of hydrolysis products/precipitates onto the membrane. With respect to phosphorus removal, dosing FeCl3 and AlCl3 achieved higher removal efficiency than using PACl. Based on lab- and pilot-scale results, dosing FeCl3 and AlCl3 at a relative dosage of over 2.5mol Me3+ per mol total phosphorus (TP) in feedwater is necessarily required to keep the TP concentration under 50μg/L in UF permeate. © 2012 Elsevier B.V.

Depleted uranium

International Nuclear Information System (INIS)

Huffer, E.; Nifenecker, H.

2001-02-01

This document deals with the physical, chemical and radiological properties of the depleted uranium. What is the depleted uranium? Why do the military use depleted uranium and what are the risk for the health? (A.L.B.)

Study on UF6 condensing receiving system improvement

International Nuclear Information System (INIS)

Zhang Zhenxing; Li Yingfeng; Li Zhenfeng; He Ping; Wang Yanping; Tian Yushan

2012-01-01

In order to improve receiving capacity of UF 6 condensing system, the pressure release mode is changed through modifying gas phase inlet of the first-grade condenser, thus pressure release time is reduced from 13.1 h to 8.1 h. Be- cause of improvement of utility condensers of the two product lines, both the flexibility of feeding nitrogen and the emergency capacity of condensers are improved greatly. And modification of fluid transferring and sampling system make the remains in system transfer flexibly. The practise shows that metal direct recovery rises to the extent, and capacity of the first-grade condensing receiving system improves 8.4%, which strongly guarantees fluorination production safely, continuously and stably run. (authors)

The approach of toxic and radiological risk equivalence in UF6 transport

International Nuclear Information System (INIS)

Ringot, C.; Hamard, J.

1989-01-01

After a brief description of the present situation concerning the safety of the transport of UF6 and the new regulation project which is being developed under the behalf of IAEA, the equivalence of radioactive and chemical risks is considered for UF6 transport regulations. The concept of low specific activity appearing misfitting to toxic gas, it is proposed a quantity limit of material, T 2 (equivalent to A 2 for radioactive materials), for packagings which do not resist to accidental conditions, (9 m drop, 800 0 C, 30 minutes fire environment). It is proposed that this limit is chosen as the release rate which is acceptable after the IAEA tests for packages having a capacity higher than T 2 kilograms. The fire being considered as the most severe situation for the toxic risk, different possible scenarios are described. This approach of risk equivalence leads to impose that the packaging resists a 800 0 C - 30 minutes fire and that in this condition the release is less than T 2 . The problem of the behaviour of the shell and the openings (in particular the valve) is raised in this context [fr

Characterization of the solid, airborne materials created when UF6 reacts with moist air flowing in single-pass mode

International Nuclear Information System (INIS)

Pickrell, P.W.

1985-10-01

A series of experiments has been performed in which UF 6 was released into flowing air in order to characterize the solid particulate material produced under non-static conditions. In two of the experiments, the aerosol was allowed to stagnate in a static chamber after release and examined further but in the other experiments characterization was done only on material collected a few seconds after release. Transmission electron microscopy and mass measurement by cascaded impactor were used to characterize the aerosol particles which were usually single spheroids with little agglomeration in evidence. The goal of the work is to determine the chemistry and physics of the UF 6 -atmospheric moisture reaction under a variety of conditions so that information about resulting species and product morphologies is available for containment and removal (knockdown) studies as well as for dispersion plume modeling and toxicology studies. This report completes the milestone for reporting the information obtained from releases of UF 6 into flowing rather than static air. 26 figs., 3 tabs

Qualification for Safeguards Purposes of UF6 Sampling using Alumina – Results of the Evaluation Campaign of ABACC-Cristallini Method

OpenAIRE

ESTAEBAN ADOLFO; GAUTIER EDUARDO; MACHADO DA SILVA LUIS; FERNANDEZ MORENO SONIA; RENHA JR GERALDO; DIAS FABIO; PEREIRA DE OLIVEIRA JUNIOR OLIVIO; AMMARAGGI DAVID; MASON PETER; SORIANO MICHAEL; CROATTO PAUL; ZULEGER EVELYN; GIAQUINTO JOSEPH; HEXEL COLE; VERCOUTER THOMAS

2017-01-01

The procedure currently used to sample material from process lines in uranium enrichment plants consists of collecting the uranium hexafluoride (UF6) in gaseous phase by desublimation inside a metal sampling cylinder cooled with liquid nitrogen or in certain facilities in a fluorothene P-10 tube type. The ABACC-Cristallini method (A-C method) has been proposed to collect the UF6 (gas) by adsorption in alumina (Al2O3) in the form of uranyl fluoride (UO2F2) (solid). This method uses a fluor...

A Role of Sp1 Binding Motifs in Basal and Large T-Antigen-Induced Promoter Activities of Human Polyomavirus HPyV9 and Its Variant UF-1

Directory of Open Access Journals (Sweden)

Ugo Moens

2017-11-01

Full Text Available Human polyomavirus 9 (HPyV9 was originally detected in the serum of a renal transplant patient. Seroepidemiological studies showed that ~20–50% of the human population have antibodies against this virus. HPyV9 has not yet been associated with any disease and little is known about the route of infection, transmission, host cell tropism, and genomic variability in circulating strains. Recently, the HPyV9 variant UF-1 with an eight base-pair deletion, a thirteen base-pair insertion and with point mutations, creating three putative Sp1 binding sites in the late promoter was isolated from an AIDS patient. Transient transfection studies with a luciferase reporter plasmid driven by HPyV9 or UF1 promoter demonstrated that UF1 early and late promoters were stronger than HPyV9 promoters in most cell lines, and that the UF1 late promoter was more potently activated by HPyV9 large T-antigen (LTAg. Mutation of two Sp1 motifs strongly reduced trans-activation of the late UF1 promoter by HPyV9 LTAg in HeLa cells. In conclusion, the mutations in the UF1 late promoter seem to strengthen its activity and its response to stimulation by HPyV9 LTAg in certain cells. It remains to be investigated whether these promoter changes have an influence on virus replication and affect the possible pathogenic properties of the virus.

Liability to disgorge profits upon breach of contract or a delict

NARCIS (Netherlands)

Schrage, E.J.H.

2013-01-01

Remedies regarding contract and tort are, generally speaking, concerned with the incidence of liability for loss or damage suffered, whereas the claim in unjust enrichment is said to require that the enrichment has occurred at the expense of the creditor. Consequently claims for breach of contract

Experimental determination of the thickness of aluminum cascade pipes in the presence of UF{sub 6} gas during enrichment measurements

Energy Technology Data Exchange (ETDEWEB)

Lombardi, M.L., E-mail: lombardi@lanl.gov [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos NM 87545 (United States); Favalli, A.; Goda, J.M.; Ianakiev, K.D.; MacArthur, D.W.; Moss, C.E. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos NM 87545 (United States)

2012-04-21

We present a method of determining the wall thickness of a pipe in a Gas Centrifuge Enrichment Plant (GCEP) when an empty pipe measurement is not feasible. Our method uses an X-ray tube for transmission measurements and a lanthanum bromide (LaBr{sub 3}) scintillation detector on the opposite side of the pipe. Two filters, molybdenum (K-edge 20.0 keV) and palladium (K-edge 24.35 keV) are used to transform the bremsstrahlung spectra produced by the X-ray tube into more useful, sharply peaked, spectra. The maximum energies of the peaks are determined by the K-edges of the filters. The attenuation properties of the uranium hexafluoride (UF{sub 6}) gas allow us to determine wall thickness by looking at the ratio of selected regions of interest (ROIs) of the Mo and Pd transmitted spectra. While the attenuation factor at these two transmission energies in the UF{sub 6} gas is nearly equal, attenuation in the aluminum pipe wall at these two energies differs by a factor of about 60. This difference allows measurement of attenuation in the pipe independent of attenuation in the UF{sub 6} gas. Feasibility studies were performed using analytical calculations, and filter thicknesses were optimized. In order to experimentally validate our attenuation measurement method, a UF{sub 6} source with variable enrichment and pipe thickness was built. We describe the experimental procedure used to verify our previous calculations and present recent results.

When employees strike back: investigating mediating mechanisms between psychological contract breach and workplace deviance.

Science.gov (United States)

Bordia, Prashant; Restubog, Simon Lloyd D; Tang, Robert L

2008-09-01

In this article, psychological contract breach, revenge, and workplace deviance are brought together to identify the cognitive, affective, and motivational underpinnings of workplace deviance. On the basis of S. L. Robinson and R. J. Bennett's (1997) model of workplace deviance, the authors proposed that breach (a cognitive appraisal) and violation (an affective response) initiate revenge seeking. Motivated by revenge, employees then engage in workplace deviance. Three studies tested these ideas. All of the studies supported the hypothesized relationships. In addition, self-control was found to be a moderator of the relationship between revenge cognitions and deviant acts; the relationship was weaker for people high in self-control.

The feasibility of nanofiltration membrane bioreactor (NF-MBR)+reverse osmosis (RO) process for water reclamation: Comparison with ultrafiltration membrane bioreactor (UF-MBR)+RO process.

Science.gov (United States)

Tay, Ming Feng; Liu, Chang; Cornelissen, Emile R; Wu, Bing; Chong, Tzyy Haur

2018-02-01

This study examines the feasibility of a novel nanofiltration membrane bioreactor (NF-MBR) followed by reverse osmosis (RO) process for water reclamation at 90% recovery and using an ultrafiltration MBR (UF-MBR)+RO as baseline for comparison. Both MBRs adopted the same external hollow fiber membrane configurations and operating conditions. The collected permeates of the MBRs were subsequently fed to the respective RO systems. The results showed that the NF-MBR (operated at a constant flux of 10 L/m 2 h) achieved superior MBR permeate quality due to enhanced biodegradation and high rejection capacity of the NF membrane, leading to lower RO fouling rates (∼3.3 times) as compared to the UF-MBR. Further analysis indicated that the cake layer fouling that caused the cake-enhanced osmotic pressure (CEOP) effect contributed predominantly to the transmembrane pressure (TMP) increase in the NF-MBR, while irreversible pore fouling was the major reason for UF membrane fouling. Furthermore, it was found that the biopolymers (i.e., organics with MW > 10 kDa) were the main components present in the foulants of the NF/UF membranes and RO membranes. The analysis indicated that the NF-MBR + RO system at recovery of 90% has comparable energy consumption as the UF-MBR + RO system at recovery of 75%. Our findings proved the feasibility of the NF-MBR + RO for water reclamation at a high recovery rate. Copyright © 2017 Elsevier Ltd. All rights reserved.

Social comparison and perceived breach of psychological contract: their effects on burnout in a multigroup analysis.

Science.gov (United States)

Cantisano, Gabriela Topa; Domínguez, J Francisco Morales; García, J Luis Caeiro

2007-05-01

This study focuses on the mediator role of social comparison in the relationship between perceived breach of psychological contract and burnout. A previous model showing the hypothesized effects of perceived breach on burnout, both direct and mediated, is proposed. The final model reached an optimal fit to the data and was confirmed through multigroup analysis using a sample of Spanish teachers (N = 401) belonging to preprimary, primary, and secondary schools. Multigroup analyses showed that the model fit all groups adequately.

A simplified physically-based breach model for a high concrete-faced rockfill dam: A case study

OpenAIRE

Qi-ming Zhong; Sheng-shui Chen; Zhao Deng

2018-01-01

A simplified physically-based model was developed to simulate the breaching process of the Gouhou concrete-faced rockfill dam (CFRD), which is the only breach case of a high CFRD in the world. Considering the dam height, a hydraulic method was chosen to simulate the initial scour position on the downstream slope, with the steepening of the downstream slope taken into account; a headcut erosion formula was adopted to simulate the backward erosion as well. The moment equilibrium method was util...

Motive Matters! An exploration of the notion ‘deliberate breach of contract’ and its consequences for the application of remedies

NARCIS (Netherlands)

M. van Kogelenberg (Martijn)

2012-01-01

textabstractThis thesis explores the notion of deliberate breach of contract and its potential remedial consequences. In the major jurisdictions in Europe and in the United States the notion of deliberate breach of contract is generally not coherently and officially defined and acknowledged as an

Impact of Acid Cleaning on the Performance of PVDF UF Membranes in Seawater Reverse Osmosis Pretreatment

KAUST Repository

Alsogair, Safiya

2016-01-01

required to maintain the characteristics of the membrane. This research was made with the purpose of investigating the effects of acid cleaning during chemically enhanced backwashing (CEB) on the performance of ultrafiltration (UF) membranes in seawater

P-T-x phase diagrams of MeF-UF4(Me=Li-Cs) systems

International Nuclear Information System (INIS)

Korenev, Yu.M.; Rykov, A.N.; Varkov, M.V.; Novoselova, A.V.

1988-01-01

Vapor composition and general pressure at three-phase equilibria in the MeF-UF 4 (Me=Li-Cs) systems are calculated using the values of independent component activities obtained earlier together with the data on fusibility diagrams. P-T and T-x projections of phase diagrams of these systems are constructed

Standard test method for determination of bromine and chlorine in UF6 and uranyl nitrate by X-Ray fluorescence (XRF) spectroscopy

CERN Document Server

American Society for Testing and Materials. Philadelphia

2001-01-01

1.1 This method covers the determination of bromine (Br) and chlorine (Cl) in uranium hexafluoride (UF6) and uranyl nitrate solution. The method as written covers the determination of bromine in UF6 over the concentration range of 0.2 to 8 μg/g, uranium basis. The chlorine in UF6 can be determined over the range of 4 to 160 μg/g, uranium basis. Higher concentrations may be covered by appropriate dilutions. The detection limit for Br is 0.2 μg/g uranium basis and for Cl is 4 μg/g uranium basis. 1.2 This standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

When it comes to securing patient health information from breaches, your best medicine is a dose of prevention: A cybersecurity risk assessment checklist.

Science.gov (United States)

Blanke, Sandra J; McGrady, Elizabeth

2016-07-01

Health care stakeholders are concerned about the growing risk of protecting sensitive patient health information from breaches. The Federal Emergency Management Agency (FEMA) has identified cyber attacks as an emerging concern, and regulations such as the Health Insurance Portability and Accountability Act (HIPAA) and the Health Information Technology for Economic and Clinical Health Act (HITECH) have increased security requirements and are enforcing compliance through stiff financial penalties. The purpose of this study is to describe health care breaches of protected information, analyze the hazards and vulnerabilities of reported breach cases, and prescribe best practices of managing risk through security controls and countermeasures. Prescriptive findings were used to construct a checklist tool to assess and monitor common risks. This research uses a case methodology to describe specific examples of the 3 major types of cyber breach hazards: portable device, insider, and physical breaches. We utilize a risk management framework to prescribe preventative actions that organizations can take to assess, analyze, and mitigate these risks. The health care sector has the largest number of reported breaches, with 3 major types: portable device, insider, and physical breaches. Analysis of actual cases indicates security gaps requiring prescriptive fixes based on "best practices." Our research culminates in a 25-item checklist that organizations can use to assess existing practices and identify security gaps requiring improvement. © 2016 American Society for Healthcare Risk Management of the American Hospital Association.

Modeling of UF{sub 6} enrichment with gas centrifuges for nuclear safeguards activities

Energy Technology Data Exchange (ETDEWEB)

Mercurio, G.; Peerani, P.; Richir, P.; Janssens, W.; Eklund, G. [European Commission, Joint Research Centre, Institute for Transuranium Elements Via Fermi, 2749-TP181,20127 Ispra (Italy)

2012-09-26

The physical modeling of uranium isotopes ({sup 235}U, {sup 238}U) separation process by centrifugation of is a key aspect for predicting the nuclear fuel enrichment plant performances under surveillance by the Nuclear Safeguards Authorities. In this paper are illustrated some aspects of the modeling of fast centrifuges for UF{sub 6} gas enrichment and of a typical cascade enrichment plant with the Theoretical Centrifuge and Cascade Simulator (TCCS). The background theory for reproducing the flow field characteristics of a centrifuge is derived from the work of Cohen where the separation parameters are calculated using the solution of a differential enrichment equation. In our case we chose to solve the hydrodynamic equations for the motion of a compressible fluid in a centrifugal field using the Berman - Olander vertical velocity radial distribution and the solution was obtained using the Matlab software tool. The importance of a correct estimation of the centrifuge separation parameters at different flow regimes, lies in the possibility to estimate in a reliable way the U enrichment plant performances, once the separation external parameters are set (feed flow rate and feed, product and tails assays). Using the separation parameters of a single centrifuge allow to determine the performances of an entire cascade and, for this purpose; the software Simulink was used. The outputs of the calculation are the concentrations (assays) and the flow rates of the enriched (product) and depleted (tails) gas mixture. These models represent a valid additional tool, in order to verify the compliance of the U enrichment plant operator declarations with the 'on site' inspectors' measurements.

Coaches in the Courtroom: Recovery in Actions for Breach of Employment Contracts.

Science.gov (United States)

Graves, Judson

1986-01-01

The rapid hiring and firing of college athletic coaches, the litigation brought in breach of employment contracts, and the special problems presented by coaching contracts have raised hard legal questions about proper methods of contract enforcement and recovery of damages. (MSE)

47 CFR 64.2011 - Notification of customer proprietary network information security breaches.

Science.gov (United States)

2010-10-01

... information security breaches. 64.2011 Section 64.2011 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Proprietary Network Information § 64.2011 Notification of customer proprietary network information security... criminal investigation or national security, such agency may direct the carrier not to so disclose or...

First HIV legal precedent in Kyrgyzstan: breach of medical privacy.

Science.gov (United States)

Iriskulbekov, Erik; Balybaeva, Asylgul

2007-12-01

A recent court case of a breach of the privacy rights of a person living with HIV/AIDS in Kyrgyzstan is the first of its kind in Central Asia, write Erik Iriskulbekov and Asylgul Balybaeva. ADILET, the NGO that brought the case to court, is one of only a few NGOs in Central Asia that provide legal assistance related to HIV and AIDS.

Practical experience of backwashing with SWRO permeate for UF fouling control

KAUST Repository

Li, Sheng; Heijman, Sebastiaan G J; Verberk, J. Q J C; Amy, Gary L.; Van Dijk, Johannis C.

2013-01-01

Effectiveness of seawater reverse osmosis (SWRO) permeate backwash on fouling control of seawater ultrafiltration was investigated at a pilot scale. A standard membrane module was used in this pilot to represent full-scale desalination plants. Results of the pilot show a good reproducibility. When the UF permeate was used for backwash, the frequency of chemically enhanced backwash (CEB) was around once per day. However, results of the pilot show that SWRO permeate backwashing could significantly reduce the CEB frequency. © 2013 Desalination Publications.

Release of UF6 from a ruptured Model 48Y cylinder at Sequoyah Fuels Corporation Facility: lessons-learned report

International Nuclear Information System (INIS)

1986-06-01

The uranium hexafluoride (UF 6 ) release of January 4, 1986, at the Sequoyah Fuels Corporation facility has been reviewed by a NRC Lessons-Learned Group. A Model 48Y cylinder containing UF 6 ruptured upon being heated after it was grossly overfilled. The Uf 6 released upon rupture of the cylinder reacted with airborne moisture to produce hydrofluoric acid (HF) and uranyl fluoride (UO 2 F 2 ). One individual died from exposure to airborne HF and several others were injured. There were no significant immediate effects from exposure to uranyl fluoride. This report of the Lessons-Learned Group presents discussions and recommendations on the process, operation and design of the facility, as well as on the responses of the licensee, NRC, and other local, state and federal agencies to the incident. It also provides recommendations in the areas of NRC licensing and inspection of fuel facility and certain other NMSS licensees. The implementation of some recommendations will depend on decisions to be made regarding the scope of NRC responsibilities with respect to those aspects of the design and operation of such facilities that are not directly related to radiological safety

Dam-breach analysis and flood-inundation mapping for selected dams in Oklahoma City, Oklahoma, and near Atoka, Oklahoma

Science.gov (United States)

Shivers, Molly J.; Smith, S. Jerrod; Grout, Trevor S.; Lewis, Jason M.

2015-01-01

Dams provide beneficial functions such as flood control, recreation, and storage of water supplies, but they also entail risk; dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure or improper operation probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning an emergency response if a dam breach occurs.

Estimation of time to rupture in a fire using 6FIRE, a lumped parameter UF6 cylinder transient heat transfer/stress analysis model

International Nuclear Information System (INIS)

Williams, W.R.; Anderson, J.C.

1995-01-01

The transportation of UF 6 is subject to regulations requiring the evaluation of packaging under a sequence of hypothetical accident conditions including exposure to a 30-min 800 degree C (1475 degree F) fire [10 CFR 71.73(c)(3)]. An issue of continuing interest is whether bare cylinders can withstand such a fire without rupturing. To address this issue, a lumped parameter heat transfer/stress analysis model (6FIRE) has been developed to simulate heating to the point of rupture of a cylinder containing UF 6 when it is exposed to a fire. The model is described, then estimates of time to rupture are presented for various cylinder types, fire temperatures, and fill conditions. An assessment of the quantity of UF 6 released from containment after rupture is also presented. Further documentation of the model is referenced

HGSYSTEM/UF6 model enhancements for plume rise and dispersion around buildings, lift-off of buoyant plumes, and robustness of numerical solver

International Nuclear Information System (INIS)

Hanna, S.R.; Chang, J.C.

1997-01-01

The HGSYSTEM/UF 6 model was developed for use in preparing Safety Analysis Reports (SARs) by estimating the consequences of possible accidental releases of UF 6 to the atmosphere at the gaseous diffusion plants (GDPs) located in Portsmouth, Ohio, and Paducah, Kentucky. Although the latter report carries a 1996 date, the work that is described was completed in late 1994. When that report was written, the primary release scenarios of interest were thought to be gas pipeline and liquid tank ruptures over open terrain away from the influence of buildings. However, upon further analysis of possible release scenarios, the developers of the SARs decided it was necessary to also consider accidental releases within buildings. Consequently, during the fall and winter of 1995-96, modules were added to HGSYSTEM/UF 6 to account for flow and dispersion around buildings. The original HGSYSTEM/UF 6 model also contained a preliminary method for accounting for the possible lift-off of ground-based buoyant plumes. An improved model and a new set of wind tunnel data for buoyant plumes trapped in building recirculation cavities have become available that appear to be useful for revising the lift-off algorithm and modifying it for use in recirculation cavities. This improved lift-off model has been incorporated in the updated modules for dispersion around buildings

Study on treating of low-level radioactive reactor wastewater by combined membrane process (UF-RO)

International Nuclear Information System (INIS)

Lu Yunyun; Cao Qiru; Chen Yunming; Huang Lijuan; Bai Xiaofeng; Li Bing; Feng Liang

2013-01-01

According to the characteristics of radionuclide exists in the low-level radioactive reactor waste water from HFETR, we use a new combined membrane process separation technology to study the efficient treating of low-lever radioactive reactor wastewater. First, the prepared the simulated wastewater contained Cs + , Sr 2+ , CO 2+ , Ni 2+ , and Fe 3+ . Then, we sequentially investigated the pressure, ion concentration, pH value and EDTA, which have effects on the desalination rate of membrane processing metal ions in wastewater. The results show that: in the condition of pH = 7, and added 0.15 mol/L EDTA, the simulated wastewater separated by UF-RO, desalination rates of Cs + , Sr 2+ , CO 2+ , Ni 2+ and Fe 3+ are all above 95%; In the subsequent trials, adding 0.15 mol/L EDTA into the radioactive residuary solution, and then treating by UF-RO-RO, the decontamination efficiency can reach 95.7%. (authors)

UF6 reconversion experience by means of Sumitomo ADU process at JCO

International Nuclear Information System (INIS)

Ogawa, H.; Yamazaki, N.

1994-01-01

Since 1973, Japan Nuclear Fuel Conversion Co., Ltd. (JCO), a leading company in Japan on nuclear fuel manufacturing, has been involved in UF 6 reconversion to ceramic grade uranium dioxide (UO 2 ) for LWR fuel by means of the original ADU process developed by Sumitomo Metal Mining Co., Ltd.. This paper deals with the details of the Sumitomo ADU process as well as the performance results of it, especially from the standpoint of product quality

Influence of UF4 physico-chemical properties on the assessment of the chronic exposure to this compound

International Nuclear Information System (INIS)

Ansoborlo, E.; Chalabreysse, J.

1990-01-01

A method was developed in order to assess uranium exposure hazards at work stations based on the industrial experience acquired by Comurhex Malvesi at Narbonne. Applied to uranium tetrafluoride (UF 4 ) the method involves 4 steps: 1. characterization of the industrial compound, including its physico-chemical properties (density, surface area, X-ray spectrum and uranium enrichment); 2. assessment of work station concentrations and particle size distribution (AMAD); 3. In vitro biological solubility with different synthetic fluids such as Gamble solutions with different gases or compounds added (oxygen or superoxide ions O 2 - ) in order to determine the solubility class D, W or Y; 4. workers' monitoring by routine measurements of urinary excretion completed, if necessary, by fecal excretion and γ-spectrometry. Results and present data on UF 4 are presented. 3 tabs., 4 figs [fr

Developments of solid materials for UF₆ sampling

Energy Technology Data Exchange (ETDEWEB)

Smith, Nicholas [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Hebden, Andrew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Savina, Joseph [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

2017-11-15

This project demonstrated that a device using majority Commercial Off the Shelf (COTS) components could be used to collect uranium hexafluoride samples safely from gaseous or solid sources. The device was based on the successful Cristallini method developed by ABACC over the past 10 years. The system was designed to capture and store the UF₆ as an inert fluoride salt to ease transportation regulations. In addition, the method was considerably faster than traditional cryogenic methods, collected enough material to perform analyses without undue waste, and could be used either inside a facility or in the storage yard.

The Relationship between Psychological Contract Breach and Organizational Commitment: Exchange Imbalance as a Moderator of the Mediating Role of Violation

Science.gov (United States)

Cassar, Vincent; Briner, Rob B.

2011-01-01

This study tested the mediating role of violation in the relationship between breach and both affective and continuance commitment and the extent to which this mediating role is moderated by exchange imbalance amongst a sample of 103 sales personnel. Results suggest that violation mediated the relationship between breach and commitment. Also,…

Thermodynamic assessment of the LiF–NaF–BeF{sub 2}–ThF{sub 4}–UF{sub 4} system

Energy Technology Data Exchange (ETDEWEB)

Capelli, E.; Beneš, O., E-mail: ondrej.benes@ec.europa.eu; Konings, R.J.M.

2014-06-01

The present study describes the full thermodynamic assessment of the LiF–NaF–BeF{sub 2}–ThF{sub 4}–UF{sub 4} system which is one of the key systems considered for a molten salt reactor fuel. The work is an extension of the previously assessed LiF–NaF–ThF{sub 4}–UF{sub 4} system with addition of BeF{sub 2} which is characterized by very low neutron capture cross section and a relatively low melting point. To extend the database the binary BeF{sub 2}–ThF{sub 4} and BeF{sub 2}–UF{sub 4} systems were optimized and the novel data were used for the thermodynamic assessment of BeF{sub 2} containing ternary systems for which experimental data exist in the literature. The obtained database is used to optimize the molten salt reactor fuel composition and to assess its properties with the emphasis on the melting behaviour.

Multi-species counter-current diffusion model for etching depleted uranium oxide in NF3, RF glow discharge

International Nuclear Information System (INIS)

Saber, H.H.; El-Genk, M.S.

1999-01-01

Results of recent experiments investigating the decontamination of depleted UO 2 using NF 3 gas, RF gloss discharge, showed that etching rate decreased monotonically with immersion time to the end point. In addition to the formation of non-volatile reaction products on UO 2 surface, the accumulation of UF 6 in the sheath contributed to the decrease in etch rate with immersion time. To investigate the latter, a transient, multi-species, counter-current diffusion model for UO 2 etching is developed. Model results indicated that, depending on gas pressure and absorbed power, the diffusion coefficient of F in the sheath decreased at the end point by ∼15%. At 17.0 Pa and 200 W, the mole fraction of F at UO 2 surface decreased rapidly with immersion time to 61% and 86% of its initial value, after one and two characteristic etch time, respectively, it became almost zero at the end point, reached after 4--5 characteristic etch times

Crevasse Splays Versus Avulsions: A Recipe for Land Building With Levee Breaches

Science.gov (United States)

Nienhuis, Jaap H.; Törnqvist, Torbjörn E.; Esposito, Christopher R.

2018-05-01

Natural-levee breaches can not only initiate an avulsion but also, under the right circumstances, lead to crevasse splay formation and overbank sedimentation. The formative conditions for crevasse splays are not well understood, yet such river sediment diversions form an integral part of billion-dollar coastal restoration projects. Here we use Delft3D to investigate the influence of vegetation and soil consolidation on the evolution of a natural-levee breach. Model simulations show that crevasse splays heal because floodplain aggradation reduces the water surface slope, decreasing water discharge into the flood basin. Easily erodible and unvegetated floodplains increase the likelihood for channel avulsions. Denser vegetation and less potential for soil consolidation result in small crevasse splays that are not only efficient sediment traps but also short-lived. Successful crevasse splays that generate the largest land area gain for the imported sediment require a delicate balance between water and sediment discharge, vegetation root strength, and soil consolidation.

The state-of-the-practice in low enriched UF6 isotopic measurements in the European Community: results of REIMEP UF6

International Nuclear Information System (INIS)

Bolle, W. de; Damen, R.; Bievre, P. de; Nagel, W.; Meyer, H.; Lycke, W.; Wolters, W.H.

1991-01-01

After the interruption of the SALE programme, CBNM has established a Regular European Interlaboratory Measurement Evaluation Programme (REIMEP) with the support of the ESARDA Working Group for techniques and standards for destructive analysis (WGDA), the ESARDA Working Group for techniques and standards for non-destructive analysis (WGNDA) and the IAEA. On the basis of a questionnaire with answers from 41 laboratories, 36 laboratories have announced their interest for such a programme. In this paper we report on the 1986/87 round of the programme establishing the measurement capability or State Of the Practice in UF 6 isotopic measurements by methods left at the discretion of the participants (thermal ionization mass spectrometry, electron impact mass spectrometry and gamma-ray spectrometry). Pictures of the State Of the Practice are presented as graphs displaying participants results

Breaching confidentiality: medical mandatory reporting laws in Iran.

Science.gov (United States)

Milanifar, Alireza; Larijani, Bagher; Paykarzadeh, Parvaneh; Ashtari, Golanna; Mehdi Akhondi, Mohammad

2014-01-01

Medical ethics is a realm where four important subjects of philosophy, medicine, theology and law are covered. Physicians and philosophers cooperation in this area will have great efficiency in the respective ethical rules formation. In addition to respect the autonomy of the patient, physician's obligation is to ensure that the medical intervention has benefit for the patient and the harm is minimal. There is an obvious conflict between duty of confidentiality and duty of mandatory reporting. Professional confidentiality is one of the basic components in building a constant physician-patient relationship which nowadays, beside the novelty, it is the subject of discussion. Legal obligation of confidentiality is not absolute. In physician-patient relationship, keeping patient's secrets and maintaining confidentiality is a legal and ethical duty, and disclosure of such secrets is mainly through specific statutes. Thus, there are a number of situations where breach of confidentiality is permitted in different legal systems. One of the situations where breaching confidentiality is permitted is the medical mandatory reporting to the relevant authority which is in accordance with many countries' legal systems. Some situations are considered in many countries legal systems' such as notification of births and deaths, infectious diseases, child abuse, sport and relevant events, medical errors, drug side effects and dangerous pregnancies. In this paper, we will examine and discuss medical mandatory reporting and its ethical and legal aspects in the judicial and legal system of Iran and few other countries. Finally we will suggest making Medical Mandatory Reporting Law in Iran.

Prediction of External Corrosion for Steel Cylinders--2002 Report

International Nuclear Information System (INIS)

Schmoyer, RLS

2002-01-01

The United States Department of Energy (DOE) manages the UF 6 Cylinder Project. The project was formed to maintain and safely manage the depleted uranium hexafluoride (UF 6 ) stored in approximately 50,000 carbon steel cylinders. The cylinders are located at three DOE sites: the East Tennessee Technology Park (ETTP) site in Oak Ridge, Tennessee; the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The System Requirements Document (SRD) (LMES 1997a) delineates the requirements of the project, and the actions needed to fulfill these requirements are specified in the System Engineering Management Plan (SEMP) (LMES 1997b). This report documents activities that in whole or part satisfy specific requirements and actions stated in the UF 6 Cylinder Project SRD and SEMP with respect to forecasting cylinder conditions. The results presented here supercede those presented by Lyon (1995, 1996, 1997, 1998, 2000), and Schmoyer and Lyon (2001). Many of the wall thickness projections made in this report are conservative, because they are based on the assumption that corrosion trends will continue, despite activities such as improved monitoring, relocations to better storage, painting, and other improvements in storage conditions relative to the conditions at the times most of the wall thickness measurements were made. For thin-wall cylinders (design nominal wall thickness 312.5 mils), the critical minimum wall thicknesses criteria used in this report are 0 (breach), 62.5 mils, and 250 mils (1 mil = 0.001 in.). For thick-wall cylinders (design nominal wall thickness 625 mils), the thickness criteria used in this report are 0, 62.5 mils, and 500 mils. The criteria triples are preliminary boundaries identified within the project that indicate (1) loss of material (UF 6 ), (2) safe handling and stacking operations, and (3) standards for off-site transport and contents transfer criteria, respectively

Sensibility analysis of fuel depletion using different nuclear fuel depletion codes

Energy Technology Data Exchange (ETDEWEB)

Martins, F.; Velasquez, C.E.; Castro, V.F.; Pereira, C.; Silva, C. A. Mello da, E-mail: felipmartins94@gmail.com, E-mail: carlosvelcab@hotmail.com, E-mail: victorfariascastro@gmail.com, E-mail: claubia@nuclear.ufmg.br, E-mail: clarysson@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

2017-07-01

Nowadays, the utilization of different nuclear codes to perform the depletion and criticality calculations has been used to simulated nuclear reactors problems. Therefore, the goal is to analyze the sensibility of the fuel depletion of a PWR assembly using three different nuclear fuel depletion codes. The burnup calculations are performed using the codes MCNP5/ORIGEN2.1 (MONTEBURNS), KENO-VI/ORIGEN-S (TRITONSCALE6.0) and MCNPX (MCNPX/CINDER90). Each nuclear code performs the burnup using different depletion codes. Each depletion code works with collapsed energies from a master library in 1, 3 and 63 groups, respectively. Besides, each code uses different ways to obtain neutron flux that influences the depletions calculation. The results present a comparison of the neutronic parameters and isotopes composition such as criticality and nuclides build-up, the deviation in results are going to be assigned to features of the depletion code in use, such as the different radioactive decay internal libraries and the numerical method involved in solving the coupled differential depletion equations. It is also seen that the longer the period is and the more time steps are chosen, the larger the deviation become. (author)

Sensibility analysis of fuel depletion using different nuclear fuel depletion codes

International Nuclear Information System (INIS)

Martins, F.; Velasquez, C.E.; Castro, V.F.; Pereira, C.; Silva, C. A. Mello da

2017-01-01

Nowadays, the utilization of different nuclear codes to perform the depletion and criticality calculations has been used to simulated nuclear reactors problems. Therefore, the goal is to analyze the sensibility of the fuel depletion of a PWR assembly using three different nuclear fuel depletion codes. The burnup calculations are performed using the codes MCNP5/ORIGEN2.1 (MONTEBURNS), KENO-VI/ORIGEN-S (TRITONSCALE6.0) and MCNPX (MCNPX/CINDER90). Each nuclear code performs the burnup using different depletion codes. Each depletion code works with collapsed energies from a master library in 1, 3 and 63 groups, respectively. Besides, each code uses different ways to obtain neutron flux that influences the depletions calculation. The results present a comparison of the neutronic parameters and isotopes composition such as criticality and nuclides build-up, the deviation in results are going to be assigned to features of the depletion code in use, such as the different radioactive decay internal libraries and the numerical method involved in solving the coupled differential depletion equations. It is also seen that the longer the period is and the more time steps are chosen, the larger the deviation become. (author)

UF6 fissile mass flow simulation at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Mihalczo, J.T.; March-Leuba, J.; Valentine, T.E.; Mattingly, J.K.; Uckan, T.; McEvers, J.A.

1997-01-01

Basis for measuring fissile mass flow in slurries, liquid, and gaseous streams is activation of a fissile stream by neutrons and then detection of delayed radiation from resulting fission products. This paper describes recent simulation measurements with the first prototype of the system for fissile mass flow measurements with HEU UF 6 gas for use in blenddown facilities. Theory was only 15% higher than actual measured; thus calibration factor would be 0.85. This simulation of HEU gas flow confirms well the understanding of the physical phenomena associated with this measurement system

A realidade da pesquisa no DEN/UFS

Directory of Open Access Journals (Sweden)

Delvair de Brito Alves

1998-12-01

Full Text Available Esta pesquisa trata do processo de pesquisar no Departamento de Enfermagem e Nutrição da Universidade Federal de Sergipe - DEN/UFS. Ela foi desenvolvida a partir de entrevistas semi estruturadas realizadas com as docentes. Dos materiais obtidos, apresentamos concepções das docentes sobre grupos, linhas e projetos de pesquisa; a produção científica docente e discente; dificuldades e possibilidades relativas à atividade de pesquisar; estratégias que esse Departamento vem utilizando para o desenvolvimento da pesquisa, para a capacitação docente e formação de pesquisadores, além da inserção de estudantes (de graduação e de pós graduação no "mundo científico". Ela conclui pela necessidade de aprofundamento dessa atividade e pela divulgação e aplicação dos seus resultados na prática de enfermagem.

CISG DEL II og Værneting i UfR 1998.1092 ØLK

DEFF Research Database (Denmark)

Lookofsky, Joseph

1998-01-01

I UfR 1998.1092 ØLK anvender en dansk domstol reglerne om købsaftalers indgåelse i CISG-konventionens del II. Det sker for at afgøre, om der er værneting i Danmark efter EF-domskonventionens artikel 5, nr. 1, når sagsøgte bestrider, at der er indgået en købsaftale. Sagen sætter fokus på behovet...

Removal of uranium and thorium from aqueous solution by ultrafiltration (UF) and PAMAM dendrimer assisted ultrafiltration (DAUF)

International Nuclear Information System (INIS)

Ilaiyaraja, P.; Ashish Kumar Singha Deb; Ponraju, D.

2015-01-01

Studies on removal of U(VI) and Th(IV) from aqueous solution have been carried out by ultrafiltration (UF) and dendrimer assisted ultrafiltration (DAUF) using regenerated cellulose acetate membrane and PAMAM [poly(amido)amine] dendrimer chelating agent. In UF, the U(VI) and Th(IV) are removed from aqueous solution by adsorption/mass deposition on the membrane at pH > 4. In DAUF, the water soluble PAMAM dendrimer chelating agent effectively concentrates these metal ions in retentate thereby preventing the mass deposition on membrane. At acidic pH (≤3), the binding of metal ions with PAMAM dendrimer is very weak and hence PAMAM can be regenerated and reused. Electronic supplementary material. The online version of this article (doi:10.1007/s10967-014-3462-x) contains supplementary material, which is available to authorized users. (author)

Paternalistic breaches of confidentiality in prison: mental health professionals' attitudes and justifications.

Science.gov (United States)

Elger, Bernice Simone; Handtke, Violet; Wangmo, Tenzin

2015-06-01

This manuscript presents mental health practitioners' (MHPs) practice, attitudes and justifications for breaching confidentiality when imprisoned patients disclose suicidal thoughts or abuse by others. 24 MHPs working in Swiss prisons shared their experiences regarding confidentiality practices. The data were analysed qualitatively and MHPs' attitudes and course of action were identified. Analysis revealed paternalistic breaches of confidentiality. When patients reported suicidal thoughts and abuse, MHPs believed that forgoing confidentiality is necessary to protect patients, providing several justifications for it. Patients were informed that such information will be transmitted without their consent to medical and non-medical prison personnel. With reference to suicidal attempts, MHPs resorted to methods that may reduce suicidal attempts such as transfer to hospital or internal changes in living arrangements, which would require provision of certain information to prison guards. In cases of abuse, some MHPs convinced patients to accept intervention or sometimes overrode competent patients' refusals to report. Also in the case of abuse, provision of limited information to other prison personnel was seen as an acceptable method to protect patients from further harm. Breaches of confidentiality, whether limited or full, remain unethical, when used for competent patients based solely on paternalistic justifications. Institutionalising ethical and legal procedures to address suicidal and abuse situations would be helpful. Education and training to help both medical and prison personnel to respond to such situations in an appropriate manner that ensures confidentiality and protects patients from suicide and abuse are necessary. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

One after the other : Effects of sequence patterns of breaches and overfulfilled obligations

NARCIS (Netherlands)

de Jong, Jeroen; Rigotti, Thomas; Mulder, J.

2017-01-01

To date, the study of psychological contracts has primarily centred on the question how retrospective evaluations of the psychological contract impact employee attitudes and behaviours, and/or focus on individual coping processes in explaining responses to breached or overfulfilled obligations. In

Quick Look Report for Chemical Reactivity Modeling of Various Multi-Canister Overpack Breaches

Energy Technology Data Exchange (ETDEWEB)

Bratton, Robert Lawrence

2002-04-01

This report makes observations or shows trends in the response and does not specifically provide conclusions or predict the onset of bulk uranium oxidation safety margins based on hole size. Comprehensive analysis will be provided in the future. The report should animate discussions about the results and what should be analyzed further in the final analysis. This report intends only to show the response of the breached multi-canister overpack (MCO) as a function of event time using the GOTH_SNF computer code. The response will be limited to physical quantities available on the exterior of the MCO. The GOTH_SNF model is approximate, because not all physical phenomenon was included in the model. Error estimates in the response are not possible at this time, because errors in the actual physical data are not known. Sensitivities in the results from variations in the physical data have not been pursued at this time, either. This effort was undertaken by the National Spent Nuclear Fuel Program to evaluate potential chemical reactivity issues of a degraded uranium metal spent nuclear fuel using the MCO fully loaded with Mark IV N-reactor fuel as the evaluation model. This configuration is proposed for handling in the Yucca Mountain Project (YMP) surface facility. Hanford is loading N-reactor fuel elements into the MCO for interim storage at the Hanford site with permanent disposal proposed at YMP. A portion of the N-reactor fuel inventory has suffered corrosion, exposing the uranium metal under the zircaloy cladding. Because of the sealed MCO, the local radiation field, and decay heat of the fuel, hydrogen production cannot be ruled out from the metal hydrates on the surface of the zircaloy cladding and exposed fuel. Because of the much greater surface area, the oxyhydroxide composition, and water of hydration in the uranium metal corrosion product, the corrosion product will be a significant water source that may equal the absorbed water on the zircaloy cladding. A

"When the going gets tough, who keeps going?" Depletion sensitivity moderates the ego-depletion effect.

Science.gov (United States)

Salmon, Stefanie J; Adriaanse, Marieke A; De Vet, Emely; Fennis, Bob M; De Ridder, Denise T D

2014-01-01

Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS) was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion.

When the Going Gets Tough, Who Keeps Going? Depletion Sensitivity Moderates the Ego-Depletion Effect

Directory of Open Access Journals (Sweden)

Stefanie J. Salmon

2014-06-01

Full Text Available Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion.

Spectroscopic properties of K{sub 5}Li{sub 2}UF{sub 10}

Energy Technology Data Exchange (ETDEWEB)

Karbowiak, M. [Faculty of Chemistry, University of WrocIaw, ul. F. Joliot-Curie 14, 50-383 WrocIaw (Poland)]. E-mail: karb@wchuwr.chem.uni.wroc.pl; Gajek, Z. [W. Trzebiatowski Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P.O. Box 1410, 50-950 WrocIaw (Poland); Drozdzynski, J. [Faculty of Chemistry, University of WrocIaw, ul. F. Joliot-Curie 14, 50-383 WrocIaw (Poland)

2005-04-04

A new uranium (III) fluoro-complex of the formula K{sub 5}Li{sub 2}UF{sub 10} has been synthesised and characterised by X-ray powder diffraction and electronic absorption spectra measurements. The compound crystallises in the orthorhombic system, space group Pnma, with a = 20.723, b = 7.809, c = 6.932 A, V = 1121.89 A{sup 3}, Z = 4 and is isostructural with its K{sub 5}Li{sub 2}NdF{sub 10} and K{sub 5}Li{sub 2}LaF{sub 10} analogous. The absorption spectrum of a polycrystalline sample of K{sub 5}Li{sub 2}UF{sub 10} was recorded at 4.2 K in the 3500-45,000 cm{sup -1} range and is discussed. The observed crystal-field levels were assigned and fitted to parameters of the simplified angular overlap model (AOM) and next to those of a semi-empirical Hamiltonian, which was representing the combined atomic and one-electron crystal-field interactions. The starting values of the AOM parameters were obtained from ab initio calculations. The analysis of the spectra enabled the assignment of 71 crystal-field levels of U{sup 3+} with a relatively small r.m.s. deviation of 37 cm{sup -1}. The total splitting of 714 cm{sup -1} was calculated for the {sup 4}I{sub 9/2} ground multiplet.

Transient response and radiation dose estimates for breaches to a spent fuel processing facility

Energy Technology Data Exchange (ETDEWEB)

Solbrig, Charles W., E-mail: soltechco@aol.com; Pope, Chad; Andrus, Jason

2014-08-15

Highlights: • We model doses received from a nuclear fuel facility from boundary leaks due to an earthquake. • The supplemental exhaust system (SES) starts after breach causing air to be sucked into the cell. • Exposed metal fuel burns increasing pressure and release of radioactive contamination. • Facility releases are small and much less than the limits showing costly refits are unnecessary. • The method presented can be used in other nuclear fuel processing facilities. - Abstract: This paper describes the analysis of the design basis accident for Idaho National Laboratory Fuel Conditioning Facility (FCF). The facility is used to process spent metallic nuclear fuel. This analysis involves a model of the transient behavior of the FCF inert atmosphere hot cell following an earthquake initiated breach of pipes passing through the cell boundary. Such breaches allow the introduction of air and subsequent burning of pyrophoric metals. The model predicts the pressure, temperature, volumetric releases, cell heat transfer, metal fuel combustion, heat generation rates, radiological releases and other quantities. The results show that releases from the cell are minimal and satisfactory for safety. This analysis method should be useful in other facilities that have potential for damage from an earthquake and could eliminate the need to back fit facilities with earthquake proof boundaries or lessen the cost of new facilities.

Transient response and radiation dose estimates for breaches to a spent fuel processing facility

International Nuclear Information System (INIS)

Solbrig, Charles W.; Pope, Chad; Andrus, Jason

2014-01-01

Highlights: • We model doses received from a nuclear fuel facility from boundary leaks due to an earthquake. • The supplemental exhaust system (SES) starts after breach causing air to be sucked into the cell. • Exposed metal fuel burns increasing pressure and release of radioactive contamination. • Facility releases are small and much less than the limits showing costly refits are unnecessary. • The method presented can be used in other nuclear fuel processing facilities. - Abstract: This paper describes the analysis of the design basis accident for Idaho National Laboratory Fuel Conditioning Facility (FCF). The facility is used to process spent metallic nuclear fuel. This analysis involves a model of the transient behavior of the FCF inert atmosphere hot cell following an earthquake initiated breach of pipes passing through the cell boundary. Such breaches allow the introduction of air and subsequent burning of pyrophoric metals. The model predicts the pressure, temperature, volumetric releases, cell heat transfer, metal fuel combustion, heat generation rates, radiological releases and other quantities. The results show that releases from the cell are minimal and satisfactory for safety. This analysis method should be useful in other facilities that have potential for damage from an earthquake and could eliminate the need to back fit facilities with earthquake proof boundaries or lessen the cost of new facilities

Tight ceramic UF membrane as RO pre-treatment: The role of electrostatic interactions on phosphate rejection

NARCIS (Netherlands)

Shang, R.; Verliefde, A.R.D.; Hu, J.; Zeng, Z; Lu, L.; Lu, L.; Kemperman, Antonius J.B.; Deng, H.; Nijmeijer, Dorothea C.; Heijman, S.G.J.; Rietveld, L.C.

2014-01-01

Phosphate limitation has been reported as an effective approach to inhibit biofouling in reverse osmosis (RO) systems for water purification. The rejection of dissolved phosphate by negatively charged TiO2 tight ultrafiltration (UF) membranes (1 kDa and 3 kDa) was observed. These membranes can

Releases of UF6 to the atmosphere after a potential fire in a cylinder storage yard

International Nuclear Information System (INIS)

Lombardi, D.A.; Williams, W.R.; Anderson, J.C.

1997-01-01

Uranium hexafluoride (UF 6 ), a toxic material, is stored in just over 6200 cylinders at the K-25 site in Oak Ridge, Tennessee. The safety analysis report (SAR) for cylinder yard storage operations at the plant required the development of accident scenarios for the potential release of UF 6 to the atmosphere. In accordance with DOE standards and guidance, the general approach taken in this SAR was to examine the functions and contents of the cylinder storage yards to determine whether safety-significant hazards were present for workers in the immediate vicinity, workers on-site, the general public off-site, or the environment. and to evaluate the significance of any hazards that were found. A detailed accident analysis was performed to determine a set of limiting accidents that have potential for off-site consequences. One of the limiting accidents identified in the SAR was the rupture of a cylinder engulfed in a fire

Analysis of enriched HF-UF6 systems. Influence by impurity and density upon the value of the multiplication

International Nuclear Information System (INIS)

Acosta, N.B.; Canavese, S.I.; Lopez, M.L.

1990-01-01

The purpose of this paper is analyzing the influence of impurity in hydrogen fluoride and in density variation (UF 6 -HF) upon the value of the effective multiplication factor (Kef) in enriched uranium hexafluoride and hydrogen fluoride systems. The identification of the values of such multiplication factors were performed by means of the Monte-Carlo (MONK V.II) code, which is specific for criticality problems. Diverse systems were considered by keeping the same geometry and varying the density value and the impurity percentages, while the assumptions made for each model were described on a case-by-case basis. Also, systems with and without water infinite reflector were evaluated. Finally, an analysis is made of the influence of each parameter upon the effective multiplication factor, in the postulated enriched UF 6 -HF systems. (Author) [es

Impact of Acid Cleaning on the Performance of PVDF UF Membranes in Seawater Reverse Osmosis Pretreatment

KAUST Repository

Alsogair, Safiya

2016-05-05

Low-pressure membrane systems such as Microfiltration (MF) and Ultrafiltration (UF) have been presented as viable option to pre-treatment systems in potable water applications. UF membranes are sporadically backwashed with ultra-filtered water to remove deposited matter from the membrane and restore it. Several factors that may cause permeability and selectivity decrease are involved and numerous procedures are applicable to achieve this objective. Membrane cleaning is the most important step required to maintain the characteristics of the membrane. This research was made with the purpose of investigating the effects of acid cleaning during chemically enhanced backwashing (CEB) on the performance of ultrafiltration (UF) membranes in seawater reverse osmosis (SWRO) pretreatment. To accomplish this, the questions made were: Does the acid addition (before or after the alkali CEB) influence the overall CEB cleaning effectiveness on Dow UF membrane? Does the CEB order of alkali (NaOCl) and acid (H2SO4) affect the overall CEB cleaning effectiveness? If yes, which order is better/worse? What is the optimal acid CEB frequency that will ensure the most reliable performance of the UF?. To answer this queries, a series of sequences were carried out with different types of chemical treatments: Only NaOCl, daily NaOCl plus weekly acid, daily NaOCl plus daily acid, and weekly acid plus daily NaOCl. To investigate the consequence of acid by studying the effect of operational data like the trans-pressure membrane, resistance or permeability and support that by the analytical experiments (organic, inorganic and microbial characterization). Microorganisms were removed almost completely at hydraulic cleaning and showed no difference with addition of acid. As a conclusion of the operational data the organic and inorganic chatacterization resulted in the elimination of the first sequence due to the acummulation of fouling over time, which produces that the cleaning increases downtime

Validation of Cristallini Sampling Method for UF6 by High Precision Double-Spike Measurements Collaboration between JRC-G.2, Team METRO and SGAS/IAEA

OpenAIRE

RICHTER Stephan; HIESS Joe; JAKOBSSON Ulf

2016-01-01

The so-called "Cristallini Method" for sampling of UF6 by adsorption and hydrolysis in alumina pellets inside a fluorothene P-10 tube has been developed by the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) several years ago [1]. This method has several advantages compared to the currently used sampling method, for which UF6 is distilled into a stainless steel tube for transportation, with hydrolysis and isotopic analysis being performed after shipping to t...

Biodegradation behavior of natural organic matter (NOM) in a biological aerated filter (BAF) as a pretreatment for ultrafiltration (UF) of river water

KAUST Repository

Huang, Guocheng

2011-04-15

In this study, biodegradation of natural organic matter (NOM) in a biological aerated filter (BAF) as pretreatment of UF treating river water was investigated. Photometric measurement, three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy and liquid chromatography with online organic carbon detector (LC-OCD) were used to investigate the fate of NOM fractions in the BAF+UF process. Results showed that the BAF process could effectively remove particles and parts of dissolved organic matter, which led to a lower NOM loading in the UF system, but different NOM fractions showed different biodegradation potentials. Further biodegradation batch experiments confirmed this observation and identified that polysaccharides and proteins (quantified using photometric methods) contained a large proportion of readily biodegradable matter while humic substances were mainly composed of inert organic substances. According to EEM measurements, it is evident that protein-like substances were more readily eliminated by microorganisms than humic-like substances. LC-OCD data also supported the phenomena that the polysaccharides and large-size proteins were more degradable than humic substances. © 2011 Springer-Verlag.

Advanced sodium fast reactor accident source terms :

Energy Technology Data Exchange (ETDEWEB)

Powers, Dana Auburn; Clement, Bernard; Denning, Richard; Ohno, Shuji; Zeyen, Roland

2010-09-01

An expert opinion elicitation has been used to evaluate phenomena that could affect releases of radionuclides during accidents at sodium-cooled fast reactors. The intent was to identify research needed to develop a mechanistic model of radionuclide release for licensing and risk assessment purposes. Experts from the USA, France, the European Union, and Japan identified phenomena that could affect the release of radionuclides under hypothesized accident conditions. They qualitatively evaluated the importance of these phenomena and the need for additional experimental research. The experts identified seven phenomena that are of high importance and have a high need for additional experimental research: High temperature release of radionuclides from fuel during an energetic event <U+F0B7> Energetic interactions between molten reactor fuel and sodium coolant and associated transfer of radionuclides from the fuel to the coolant <U+F0B7> Entrainment of fuel and sodium bond material during the depressurization of a fuel rod with breached cladding <U+F0B7> Rates of radionuclide leaching from fuel by liquid sodium <U+F0B7> Surface enrichment of sodium pools by dissolved and suspended radionuclides <U+F0B7> Thermal decomposition of sodium iodide in the containment atmosphere <U+F0B7> Reactions of iodine species in the containment to form volatile organic iodides. Other issues of high importance were identified that might merit further research as development of the mechanistic model of radionuclide release progressed.

MINIMIZING GLOVEBOX GLOVE BREACHES, PART IV: CONTROL CHARTS

International Nuclear Information System (INIS)

Cournoyer, Michael E.; Lee, Michelle B.; Schreiber, Stephen B.

2007-01-01

At the Los Alamos National Laboratory (LANL) Plutonium Facility, plutonium. isotopes and other actinides are handled in a glovebox environment. The spread of radiological contamination, and excursions of contaminants into the worker's breathing zone, are minimized and/or prevented through the use of glovebox technology. Evaluating the glovebox configuration, the glovebo gloves are the most vulnerable part of this engineering control. Recognizing this vulnerability, the Glovebox Glove Integrity Program (GGIP) was developed to minimize and/or prevent unplanned openings in the glovebox environment, i.e., glove failures and breaches. In addition, LANL implement the 'Lean Six Sigma (LSS)' program that incorporates the practices of Lean Manufacturing and Six Sigma technologies and tools to effectively improve administrative and engineering controls and work processes. One tool used in LSS is the use of control charts, which is an effective way to characterize data collected from unplanned openings in the glovebox environment. The benefit management receives from using this tool is two-fold. First, control charts signal the absence or presence of systematic variations that result in process instability, in relation to glovebox glove breaches and failures. Second, these graphical representations of process variation detennine whether an improved process is under control. Further, control charts are used to identify statistically significant variations (trends) that can be used in decision making to improve processes. This paper discusses performance indicators assessed by the use control charts, provides examples of control charts, and shows how managers use the results to make decisions. This effort contributes to LANL Continuous Improvement Program by improving the efficiency, cost effectiveness, and formality of glovebox operations.

Method of absorbing UF6 from gaseous mixtures in alkamine absorbents

International Nuclear Information System (INIS)

Lafferty, R.H.; Smiley, S.H.; Radimer, K.J.

1976-01-01

A method is described for recovering UF 6 from gaseous mixtures by absorption in a liquid. The liquid absorbent must have a relatively low viscosity and at least one component of the absorbent is an alkamine having less than 3 carbon atoms bonded to the amino nitrogen, less than 2 of the carbon atoms other than those bonded to the amino nitrogen are free of the hydroxy radical and precipitate the absorbed uranium from the absorbent. At least one component of the absorbent is chosen from the group consisting of ethanolamine, diethanolamine, and 3-methyl-3-amino-propane-diol-1,2

Finite element modelling of fire situations in UF6 transport containers

International Nuclear Information System (INIS)

Basombrio, F.G.

1996-01-01

In this report we describe some runs made with the code FASES2. They concern different situations associated to fires originated by accidents in the transport of containers filled with UF6. Such situations have been inspired in cases taken from the current literature, and related to numerical modelling or experiments. We aim to consign the most relevant aspects of such runs, with the future purpose of comparing them with the predictions made with simpler lumped models. In such a way, it will be possible to calibrate the simple models with the results coming from detailed models. (author). 6 refs., 12 figs

Transport of Powders through Rotary Kilns: Experimental Study and Modelling

OpenAIRE

Debacq , Marie; Hartmann , Didier; Houzelot , Jean-Leon; Ablitzer , Denis

1999-01-01

International audience; During the nuclear fuel cycle, uranium as hexafluoride is enriched by means of gaseous-diffusion process. The depleted UF6 resulting from the isotope separation stage is converted into U3O8 to enable its safe storage (conversion carried out by COGEMA). The UF6 -> UO2 conversion is performed in four identical plants : UF6 is hydrolysed in the gaseous phase through a vertical reactor, then the UO2F2 powder formed is pyrohydrolysed into U3O8 powder through a lightly incli...

Perceived Control and Psychological Contract Breach as Explanations of the Relationships Between Job Insecurity, Job Strain and Coping Reactions: Towards a Theoretical Integration.

Science.gov (United States)

Vander Elst, Tinne; De Cuyper, Nele; Baillien, Elfi; Niesen, Wendy; De Witte, Hans

2016-04-01

This study aims to further knowledge on the mechanisms through which job insecurity is related to negative outcomes. Based on appraisal theory, two explanations-perceived control and psychological contract breach-were theoretically integrated in a comprehensive model and simultaneously examined as mediators of the job insecurity-outcome relationship. Different categories of outcomes were considered, namely work-related (i.e. vigour and need for recovery) and general strain (i.e. mental and physical health complaints), as well as psychological (i.e. job satisfaction and organizational commitment) and behavioural coping reactions (i.e. self-rated performance and innovative work behaviour). The hypotheses were tested using data of a heterogeneous sample of 2413 Flemish employees by means of both single and multiple mediator structural equation modelling analyses (bootstrapping method). Particularly, psychological contract breach accounted for the relationship between job insecurity and strain. Both perceived control and psychological contract breach mediated the relationships between job insecurity and psychological coping reactions, although the indirect effects were larger for psychological contract breach. Finally, perceived control was more important than psychological contract breach in mediating the relationships between job insecurity and behavioural coping reactions. This study meets previous calls for a theoretical integration regarding mediators of the job insecurity-outcome relationship. Copyright © 2014 John Wiley & Sons, Ltd.

Finite element modelling of fire situations in UF6 transport containers; Modelado por elementos finitos de situaciones de incendio en contenedores para el transporte de UF6

Energy Technology Data Exchange (ETDEWEB)

Basombrio, F G

1997-12-31

In this report we describe some runs made with the code FASES2. They concern different situations associated to fires originated by accidents in the transport of containers filled with UF6. Such situations have been inspired in cases taken from the current literature, and related to numerical modelling or experiments. We aim to consign the most relevant aspects of such runs, with the future purpose of comparing them with the predictions made with simpler lumped models. In such a way, it will be possible to calibrate the simple models with the results coming from detailed models. (author). 6 refs., 12 figs.

Computer-optimized γ-NDA geometries for uranium enrichment verification of gaseous UF6

International Nuclear Information System (INIS)

Wichers, V.A.; Aaldijk, J.K.; Betue, P.A.C. de; Harry, R.J.S.

1993-05-01

An improved collimator pair of novel design tailored for deposit independent enrichment verification of gaseous UF 6 at low pressures in cascade-to-header pipes of small diameters in centrifuge enrichment plants is presented. The designs are adapted for use in a dual-geometry arrangement for simultaneous measurements with both detection geometries. The average measurement time with the dual-geometry arrangement is approximately half an hour for deposit-to-gas activity ratios as high as 20. (orig.)

Deuterium-depleted water

International Nuclear Information System (INIS)

Stefanescu, Ion; Steflea, Dumitru; Saros-Rogobete, Irina; Titescu, Gheorghe; Tamaian, Radu

2001-01-01

Deuterium-depleted water represents water that has an isotopic content smaller than 145 ppm D/(D+H) which is the natural isotopic content of water. Deuterium depleted water is produced by vacuum distillation in columns equipped with structured packing made from phosphor bronze or stainless steel. Deuterium-depleted water, the production technique and structured packing are patents of National Institute of Research - Development for Cryogenics and Isotopic Technologies at Rm. Valcea. Researches made in the last few years showed the deuterium-depleted water is a biological active product that could have many applications in medicine and agriculture. (authors)

Psychological contract breach and work performance: Is social exchange a buffer or an intensifier?

NARCIS (Netherlands)

Bal, P.M.; Chiaburu, D.S.; Jansen, P.G.W.

2010-01-01

Purpose: The aim of this paper is to investigate how social exchanges modify the relationship between psychological contract breach and work performance. It aims to present two concurrent hypotheses, based on theoretical interaction effects of social exchanges (conceptualized as social exchange

Pinhole Breaches in Spent Fuel Containers: Improvements to Conservative Models of Aerosol Release and Plugging

International Nuclear Information System (INIS)

Casella, Andrew M.; Loyalka, Sudarsham K.; Hanson, Brady D.

2007-01-01

By taking the differential forms of transport and equations of state, the equations describing aerosol transport in pinhole breaches can be solved directly using continuous models. The results are compared with discrete models.

A guide to California's breaches. First year of state reporting requirement reveals common privacy violations.

Science.gov (United States)

Dimick, Chris

2010-04-01

Effective January 1, 2009, California healthcare providers were required to report every breach of patient information to the state. They have sent a flood of mishaps and a steady stream of malicious acts.

Hybrid coagulation-UF processes for spent filter backwash water treatment: a comparison studies for PAFCl and FeCl3 as a pre-treatment.

Science.gov (United States)

Ebrahimi, Afshin; Amin, Mohammad Mehdi; Pourzamani, Hamidreza; Hajizadeh, Yaghoub; Mahvi, Amir Hossein; Mahdavi, Mokhtar; Rad, Mohammad Hassan Rabie

2017-08-01

In this study, the reclamation of clean water from spent filter backwash water (SFBW) was investigated through pilot-scale experiments. The pilot plant consisted of pre-sedimentation, coagulation, flocculation, clarification, and ultrafiltration (UF). Two coagulants of PAFCl and FeCl 3 were investigated with respect to their performance on treated SFBW quality and UF membrane fouling. At the optimum dose of PAFCl and FeCl 3 turbidity removal of 99.6 and 99.4% was attained, respectively. PAFCl resulted in an optimum UV 254 , TOC, and DOC removal of 80, 83.6, and 72.7%, respectively, and FeCl 3 caused the removal of those parameters by 76.7, 80.9, and 65.9%, respectively. PAFCl removed hydrophilic and transphilic constituent better than FeCl 3 , but FeCl 3 had, to some extent, higher affinities to a hydrophobic fraction. It was concluded that PAFCl showed a better coagulation performance in most cases and caused a lower membrane fouling rate compared to FeCl 3 . Finally, the treated SFBW with both coagulant-UF systems met the drinking water standards.

A Depth-Averaged 2-D Simulation for Coastal Barrier Breaching Processes

Science.gov (United States)

2011-05-01

including bed change and variable flow density in the flow continuity and momentum equations. The model adopts the HLL approximate Riemann solver to handle...flow density in the flow continuity and momentum equations. The model adopts the HLL approximate Riemann solver to handle the mixed-regime flows near...18 547 Keulegan equation or the Bernoulli equation, and the breach morphological change is determined using simplified sediment transport models

Ego depletion in visual perception: Ego-depleted viewers experience less ambiguous figure reversal.

Science.gov (United States)

Wimmer, Marina C; Stirk, Steven; Hancock, Peter J B

2017-10-01

This study examined the effects of ego depletion on ambiguous figure perception. Adults (N = 315) received an ego depletion task and were subsequently tested on their inhibitory control abilities that were indexed by the Stroop task (Experiment 1) and their ability to perceive both interpretations of ambiguous figures that was indexed by reversal (Experiment 2). Ego depletion had a very small effect on reducing inhibitory control (Cohen's d = .15) (Experiment 1). Ego-depleted participants had a tendency to take longer to respond in Stroop trials. In Experiment 2, ego depletion had small to medium effects on the experience of reversal. Ego-depleted viewers tended to take longer to reverse ambiguous figures (duration to first reversal) when naïve of the ambiguity and experienced less reversal both when naïve and informed of the ambiguity. Together, findings suggest that ego depletion has small effects on inhibitory control and small to medium effects on bottom-up and top-down perceptual processes. The depletion of cognitive resources can reduce our visual perceptual experience.

Breach of information duties in the B2C e-commerce: adequacy of available remedies

Directory of Open Access Journals (Sweden)

Zofia Bednarz

2016-07-01

Full Text Available

B2C e-commerce is characterised by the information asymmetry between the contracting parties. Various information duties are imposed on traders, both at the European and national level to correct this asymmetry and to ensure proper market functioning. The mandated disclosure is based on the assumption of consumers' rationality. However, developments of behavioural economics challenge this assumption. The utility of mandated disclosure in consumer contracts depends also on the remedies available to consumers in a case of breach of information duties. Those remedies are often heavily influenced by the national general private law applicable to the contractual relationship between the parties. Nevertheless, since the economics of general contract law differ importantly from principles of consumer e-commerce, various problems can be associated with the application of general law remedies to the breach of information duties in B2C contracts. The limited value of the majority of the online B2C transactions is incompatible with costly and lengthy court proceedings. Moreover, breach of information duties will often not produce enough material damage on the side of the consumer to make the remedies available. Different solutions are explored, from ADR, to the duty to advise, to non-legal mechanisms making the information easier to use for consumers throughlimiting disclosure. Finally, the right of withdrawal is analysed as an example of a specific remedy, adapted to the economics of the B2C electronic transactions, where the aims parties pursue through contracts are different than in commercial contracts, and their relationship is marked with the inequality of economic power and information asymmetry. However, the legally established cooling-off period is not free from limitations, and only a combination of various measures, including effective

Role of contaminants in the fluorination of β-UO3 to UF4 by freon-12

International Nuclear Information System (INIS)

Girgis, B.S.; Rofail, N.H.

1992-01-01

Ammonium uranate was precipitated from uranyl nitrate or sulphate by NH 3 gas or urea, and decomposed to β-UO 3 by calcination at 623 or 773 K. Oxides contaminated by high contents of nitrates (non-washed uranate) displayed higher conversion to UF 4 in comparison to the respective pre-washed uranate. Products of thermal treatment at 623 K were also more reactive towards fluorination, which was ascribed to the highly-disordered, loosely bound, high surface area products. The presence of residual nitrate, and probably ammonium, ions help in the partial reduction to lower oxides and in preventing recrystallization of the reaction solids. Ammonium uranate precipitated from uranyl sulphate and decomposed at 623 K is more easily fluorinated than the product decomposed at 773 K; it is also better product for fluorination than the uranate precipitated from uranyl nitrate. The complete conversion to UF 4 i attained after 45 min with the uranate precipitated from uranyl sulphate and treated at 623 K, but it needs 120 min with the product formed from uranyl nitrate and decomposed at the same temperature. (orig.)

Quantitative and Qualitative Job Insecurity and Idea Generation: The Mediating Role of Psychological Contract Breach

Directory of Open Access Journals (Sweden)

Wendy Niesen

2018-03-01

Full Text Available This study investigates how quantitative and qualitative job insecurity relate to idea generation, a dimension of innovative work behaviour. We hypothesise that both types of job insecurity relate negatively to this type of innovative behaviour, and expect a stronger association between quantitative job insecurity and idea generation. Moreover, we argue that psychological contract breach mediates (‘explains’ these negative relationships. The hypotheses were tested in a sample of 1420 supervisors from a large Belgian organisation, using hierarchical regression analyses, bootstrapping analyses, and relative weight analysis. The results showed that both types of job insecurity are negatively associated with idea generation. Contrary to our expectations, the relationship between both forms of job insecurity and idea generation was equally strong. Psychological contract breach was found to mediate these relationships.

UF/sub 6/ test loop for evaluation and implementation of international enrichment plant safeguards

International Nuclear Information System (INIS)

Cooley, J.N.; Fields, L.W.; Swindle, D.W. Jr.

1987-01-01

A functional test loop capable of simulating UF/sub 6/ flows, pressures, and pipe deposits characteristic of gas centrifuge enrichment plant piping has been designed and fabricated by the Enrichment Safeguards Program of Martin Marietta Energy Systems, Inc., for use by the International Atomic Energy Agency (IAEA) at its Safeguards Analytical Laboratory in Seibersdorf, Austria. The purpose of the test loop is twofold: (1) to enable the IAEA to evaluate and to calibrate enrichment safeguards measurement instrumentation to be used in limited frequency-unannounced access (LFUA) inspection strategy measurements at gas centrifuge enrichment plants and (2) to train IAEA inspectors in the use of such instrumentation. The test loop incorporates actual sections of cascade header pipes from the centrifuge enrichment plants subject to IAEA inspections. The test loop is described, applications for its use by the IAEA are detailed, and results from an initial demonstration session using the test loop are summarized. By giving the IAEA the in-house capability to evaluate LFUA inspection strategy approaches, to develop inspection procedures, to calibrate instrumentation, and to train inspectors, the UF/sub 6/ cascade header pipe test loop will contribute to the IAEA's success in implementing LFUA strategy inspections at gas centrifuge enrichment facilities subject to international safeguards inspections

Electrochemical separation of uranium in the molten system LiF-NaF-KF-UF4

Science.gov (United States)

Korenko, M.; Straka, M.; Szatmáry, L.; Ambrová, M.; Uhlíř, J.

2013-09-01

This article is focused on the electrochemical investigation (cyclic voltammetry and related studies) of possible reduction of U4+ ions to metal uranium in the molten system LiF-NaF-KF(eut.)-UF4 that can provide basis for the electrochemical extraction of uranium from molten salts. Two-step reduction mechanism for U4+ ions involving one electron exchange in soluble/soluble U4+/U3+ system and three electrons exchange in the second step were found on the nickel working electrode. Both steps were found to be reversible and diffusion controlled. Based on cyclic voltammetry, the diffusion coefficients of uranium ions at 530 °C were found to be D(U4+) = 1.64 × 10-5 cm2 s-1 and D(U3+) 1.76 × 10-5 cm2 s-1. Usage of the nickel spiral electrode for electrorefining of uranium showed fairly good feasibility of its extraction. However some oxidant present during the process of electrorefining caused that the solid deposits contained different uranium species such as UF3, UO2 and K3UO2F5.

“When the going gets tough, who keeps going?” Depletion sensitivity moderates the ego-depletion effect

Science.gov (United States)

Salmon, Stefanie J.; Adriaanse, Marieke A.; De Vet, Emely; Fennis, Bob M.; De Ridder, Denise T. D.

2014-01-01

Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS) was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion. PMID:25009523

Monitoring the mass of UF6 gas and uranium deposits in aluminium pipes using X-ray fluorescence and X-ray transmission gauges

International Nuclear Information System (INIS)

Packer, T.W.; Smith, S.M.

1984-12-01

In order to determine the enrichment of UF 6 gas in centrifuge plant pipework it is necessary to measure the mass of the gas (pressure) and the mass per unit area of any uranium deposited on the pipe. This paper shows that it is possible to determine the pressure of the UF 6 gas in pipes 120 mm in diameter using an energy-dispersive X-ray fluorescence spectrometer. Results are also given of transmission measurements made using a low power X-ray generator operated at two different applied voltages. A method of using the two measurements to determine the mass per unit area of deposited uranium is described. (author)

Emergency preparedness and response in case of a fire accident with UF6 packages traversing the Suez Canal

International Nuclear Information System (INIS)

Salama, M.

2004-01-01

Egypt has a unique problem, the Suez Canal. Radioactive cargo passes regularly through the canal carrying new and spent reactor fuel. There are also about 1000 metric tonnes of uranium hexafluoride (UF 6 ) passing through the canal every year. In spite of all the precautions taken in the transport, accidents with packages containing UF 6 shipped through the Suez Canal may arise, even though the probability is minimal. Such accidents may be accompanied by injuries to or death of persons and damage to property including radiation and criticality hazards and high chemical toxicity, particularly if the accident occurred close to one of the three densely populated cities (Port Said, Ismailia and Suez), which are located along the west bank of the Suez Canal. The government of Egypt has established a national radiological emergency plan in order to deal with any radiological accidents which may arise inside the country. This paper considers the effect of a fire accident to industrial packages containing UF 6 on board a cargo ship passing along the Suez Canal near Port Said City. The accident scenario and emergency response actions taken during the different phases of the accident are presented and discussed. The paper highlights the importance of public awareness for populations located in densely populated areas along the bank of the Suez Canal, in order to react in a timely and effective way to avoid the toxic and radiological hazards resulting from such a type of accident. The possibility of upgrading the capabilities of civil defence and fire-fighting personnel is also discussed (author)

Evaluation of the Acceptability of Potential Depleted Uranium Hexafluoride Conversion Products at the Envirocare Disposal Site

Energy Technology Data Exchange (ETDEWEB)

Croff, A.G.

2001-01-11

The purpose of this report is to review and document the capability of potential products of depleted UF{sub 6} conversion to meet the current waste acceptance criteria and other regulatory requirements for disposal at the facility in Clive, Utah, owned by Envirocare of Utah, Inc. The investigation was conducted by identifying issues potentially related to disposal of depleted uranium (DU) products at Envirocare and conducting an initial analysis of them. Discussions were then held with representatives of Envirocare, the state of Utah (which is a NRC Agreement State and, thus, is the cognizant regulatory authority for Envirocare), and DOE Oak Ridge Operations. Provisional issue resolution was then established based on the analysis and discussions and documented in a draft report. The draft report was then reviewed by those providing information and revisions were made, which resulted in this document. Issues that were examined for resolution were (1) license receipt limits for U isotopes; (2) DU product classification as Class A waste; (3) use of non-DOE disposal sites for disposal of DOE material; (4) historical NRC views; (5) definition of chemical reactivity; (6) presence of mobile radionuclides; and (7) National Environmental Policy Act coverage of disposal. The conclusion of this analysis is that an amendment to the Envirocare license issued on October 5, 2000, has reduced the uncertainties regarding disposal of the DU product at Envirocare to the point that they are now comparable with uncertainties associated with the disposal of the DU product at the Nevada Test Site that were discussed in an earlier report.

No harm done? Assessing risk of harm under the federal breach notification rule.

Science.gov (United States)

Dimick, Chris

2010-08-01

Provisions within the HITECH Act require that covered entities notify individuals if their protected health information is breached. However, the current regulation allows an exemption if the risk of harm is slight. Assessing risk can be subjective, and privacy officers have been working to create methods to conduct and document their analyses.

Frequently Asked Questions (FAQs)

Science.gov (United States)

are the potential health risks from transportation of depleted uranium metal or oxide? Other Skip Navigation Depleted UF6 Logo (Go to Home Page) Uranium Quick Fact Energy from Uranium One ton of natural uranium can produce more than 40 million kilowatt-hours of electricity. This is equivalent

Market Reactions to Publicly Announced Privacy and Security Breaches Suffered by Companies Listed on the United States Stock Exchanges: A Comparative Empirical Investigation

Science.gov (United States)

Coronado, Adolfo S.

2012-01-01

Using a sample of security and privacy breaches the present research examines the comparative announcement impact between the two types of events. The first part of the dissertation analyzes the impact of publicly announced security and privacy breaches on abnormal stock returns, the change in firm risk, and abnormal trading volume are measured.…

Development of a UF{sub 6} cylinder transient heat transfer/stress analysis model

Energy Technology Data Exchange (ETDEWEB)

Williams, W.R. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31

A heat transfer/stress analysis model is being developed to simulate the heating to a point of rupture of a cylinder containing UF{sub 6} when it is exposed to a fire. The assumptions underlying the heat transfer portion of the model, which has been the focus of work to date, will be discussed. A key aspect of this model is a lumped parameter approach to modeling heat transfer. Preliminary results and future efforts to develop an integrated thermal/stress model will be outlined.

The Changing Contours of the Psychological Contract: Unpacking Context and Circumstances of Breach

Science.gov (United States)

Pate, Judy

2006-01-01

Purpose: The purpose of this paper is to propose a processual framework of psychological contract breach, which maps holistically the interactions among concepts drawn from the trust and justice literature. However, the price of a holistic picture is frequently a lack of depth of analysis of any single variable, and consequently the second part of…

Initial data report in response to the surplus plutonium disposition environmental impact statement data call for the UO2 supply. Revision 1

International Nuclear Information System (INIS)

White, V.S.; Cash, J.M.; Michelhaugh, R.D.

1997-11-01

The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program's preparation of the draft Surplus Plutonium Disposition Environmental Impact Statement. This is one of several responses to data calls generated to provide background information on activities associated with the operation of the Mixed-Oxide (MOX) Fuel Fabrication Facility. Urania feed for the MOX Fuel Fabrication Facility may be either natural or depleted. Natural uranium typically contains 0.0057 wt% 234 U, 0.711 wt% 235 U, and the majority as 238 U. The fissile isotope is 235 U, and uranium is considered depleted if the total 235 U content is less than 0.711 wt% as found in nature. The average composition of 235 U in DOE's total depleted urania inventory is 0.20 wt%. The depleted uranium assay range proposed for use in this program is 0.2500--0.2509 wt%. Approximately 30% more natural uranium would be required than depleted uranium based on the importance of maintaining a specific fissile portion in the MOX fuel blend. If the uranium component constitutes a larger quantity of fissile material, less plutonium can be dispositioned on an annual basis. The percentage composition, referred to as assay, of low-enriched uranium necessary for controlled fission in commercial light-water nuclear power reactors is 1.8--5.0 wt% 235 U. This data report provides information on the schedule, acquisition, impacts, and conversion process for using uranium, derived from depleted uranium hexafluoride (UF 6 ), as the diluent for the weapons-grade plutonium declared as surplus. The case analyzed is use of depleted UF 6 in storage at the Portsmouth Gaseous Diffusion Plant in Piketon, Ohio, being transported to a representative UF 6 to uranium dioxide conversion facility (GE Nuclear Energy) for processing, and subsequently transported to the MOX Fuel Fabrication Facility

Medical negligence based on bad faith, breach of contract, or mental anguish.

Science.gov (United States)

Ficarra, B J

1980-01-01

Financial recovery owing to breach of contract is restricted to the pecuniary amount lost because of failure to perform on the stipulated contract. With the acquisition of newer knowledge, attorneys are now utilizing the weapon of contractual failure as applied to medical negligence. The impetus to this new weapon for the plaintiff has accrued because of the favorable verdicts rendered from positive decisions based upon bad faith.

Once more unto the breach managing information security in an uncertain world

CERN Document Server

Simmons, Andrea C

2012-01-01

In Once more unto the Breach, Andrea C Simmons speaks directly to information security managers and provides an insider's view of the role, offering priceless gems from her extensive experience and knowledge. Based on a typical year in the life of an information security manager, the book examines how the general principles can be applied to all situations and discusses the lessons learnt from a real project.

Thermodynamic properties of UF sub 6 measured with a ballistic piston compressor

Science.gov (United States)

Sterritt, D. E.; Lalos, G. T.; Schneider, R. T.

1973-01-01

From experiments performed with a ballistic piston compressor, certain thermodynamic properties of uranium hexafluoride were investigated. Difficulties presented by the nonideal processes encountered in ballistic compressors are discussed and a computer code BCCC (Ballistic Compressor Computer Code) is developed to analyze the experimental data. The BCCC unfolds the thermodynamic properties of uranium hexafluoride from the helium-uranium hexafluoride mixture used as the test gas in the ballistic compressor. The thermodynamic properties deduced include the specific heat at constant volume, the ratio of specific heats for UF6, and the viscous coupling constant of helium-uranium hexafluoride mixtures.

Conceptual design for the field test and evaluation of the gas-phase UF6 enrichment meter

International Nuclear Information System (INIS)

Strittmatter, R.B.; Leavitt, J.N.; Slice, R.W.

1980-12-01

An in-line enrichment monitor is being developed to provide real-time enrichment data for the gas-phase UF 6 feed stream of an enrichment plant. Data from proof-of-principle measurements using a laboratory prototype system are presented. A conceptual design for an enrichment monitor to be field tested and evaluated at the Oak Ridge Gaseous Diffusion Plant is reported

Optimization of the isotopic analysis of UF6 by quadrupole mass spectrometry technique

International Nuclear Information System (INIS)

Porto, Peterson

2006-01-01

In the present work a procedure for determination of the isotopic ratio 238 U/ 235 U in UF 6 samples was established using a quadrupole mass spectrometer with ionization by electron impact and ion detection by Faraday cup or electron multiplier. For this, the following items were optimized in the spectrometer: the parameters in the ion source that provided the most intense peak, with good shape, for the corresponding mass of the most abundant isotope; the resolution that reduced the non linear effects and the number of analytic cycles that reduced the uncertainty in the results. The measurement process was characterized with respect to the effects of mass discrimination, linearity and memory effect. The mass discrimination showed to be linearly dependent of the sample pressure in the batch volume, for the pressure ranges from 0.15 to 0.30 mbar and from 0.30 to 0.40 mbar. The spectrometer was shown linear in the measurement of isotopic ratios between 0.005 and 0.045. The memory factor for the ion source and for the introduction system were, respectively, 1.000 ± 0.001 and 1.003 ± 0.003; the first one can be ignored, the second one can be eliminated by washing the batch volume with the new sample. A methodology for routine analysis of UF 6 samples and the determination of the uncertainties were set up in details as well. (author)

The COMURHEX 2 project. Investing in UF6 long-term security of supply

International Nuclear Information System (INIS)

Bouzon, Pierre; Lacombe, Philippe; Durante, Pierre; Teyssier, Patrick

2008-01-01

The front-end nuclear fuel supply chain for LWRs encompasses four major industrial stages that are mining and concentration, conversion, enrichment, and eventually fuel fabrication. The different stages involve uranium in different chemical and physical forms. Enrichment of the 235-U fissile isotope requires gaseous UF6. As the standard output of mine is U3O8, referred to as ''yellow cake'', a purely chemical stage is therefore needed to fluorinate U3O8 and turn it into UFe: this is the conversion stage. U3O8 inventories management is thus performed at the conversion sites.Purification of the mining concentrates is also needed prior to actual conversion into UFe. This step is important because the front-end supply chain facilities have strict specifications concerning impurities. The conversion stage may involve intermediary products, namely UO3 and/or UF4, depending on the industrial scheme implemented. With the Comurhex 2 project, AREVA is not only shaping the future of conversion market and contributing to the security of supply of its customers, but it is also developing innovative techniques and reorganizing the conversion process steps. Providing such guaranteed and valuable conversion supply with a brand new plant is our strong commitment to a sustainable nuclear fuel cycle. And AREVA is the first that has launched such a project, looking further ahead. The three main axes of sustainable development, economical, social, and environmental, are truly taken into account in the development of the new project.

Halo Star Lithium Depletion

International Nuclear Information System (INIS)

Pinsonneault, M. H.; Walker, T. P.; Steigman, G.; Narayanan, Vijay K.

1999-01-01

The depletion of lithium during the pre-main-sequence and main-sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. Previous work has indicated a wide range of possible depletion factors, ranging from minimal in standard (nonrotating) stellar models to as much as an order of magnitude in models that include rotational mixing. Recent progress in the study of the angular momentum evolution of low-mass stars permits the construction of theoretical models capable of reproducing the angular momentum evolution of low-mass open cluster stars. The distribution of initial angular momenta can be inferred from stellar rotation data in young open clusters. In this paper we report on the application of these models to the study of lithium depletion in main-sequence halo stars. A range of initial angular momenta produces a range of lithium depletion factors on the main sequence. Using the distribution of initial conditions inferred from young open clusters leads to a well-defined halo lithium plateau with modest scatter and a small population of outliers. The mass-dependent angular momentum loss law inferred from open cluster studies produces a nearly flat plateau, unlike previous models that exhibited a downward curvature for hotter temperatures in the 7Li-Teff plane. The overall depletion factor for the plateau stars is sensitive primarily to the solar initial angular momentum used in the calibration for the mixing diffusion coefficients. Uncertainties remain in the treatment of the internal angular momentum transport in the models, and the potential impact of these uncertainties on our results is discussed. The 6Li/7Li depletion ratio is also examined. We find that the dispersion in the plateau and the 6Li/7Li depletion ratio scale with the absolute 7Li depletion in the plateau, and we use observational data to set bounds on the 7Li depletion in main-sequence halo

Temperature evaluation of UF6 and cluster detection in nozzle expansion using low-resolution infrared absorption spectroscopy

International Nuclear Information System (INIS)

Sbampato, M.E.; Antunes, L.M.D.; Miranda, S.F.; Sena, S.C.; Santos, A.M.

1998-01-01

The continuous supersonic expansion of pure gaseous UF 6 and mixtures of UF 6 with argon and nitrogen through a bidimensional nozzle was studied using low-resolution infrared spectroscopy in the ν 3 absorption band region. The experiments were carried out in order to calculate the molecular temperature of the beam and also to verify cluster formation in the expansion. The molecular beam temperature evaluation was based on the measurements of the low-resolution bandwidth, which were compared to simulated spectra results. The temperatures were also evaluated using the measured pressure at the end of the nozzle by a Pitot tube. In the conditions where no cluster formation was observed the calculated theoretical temperatures using an equilibrium expansion model are in good agreement with the data obtained through the analysis of the experimental spectra and through the Pitot tube pressure measurement. Cluster formation was observed for temperatures below about 120 K. In these conditions the infrared spectra showed shoulders in the region above 630 cm -1 and a shoulder or band between 616 and 600 cm -1 . (orig.)

Draft Environmental Impact Statement for Construction and Operation of a Depleted Uranium Hexafluoride Conversion Facility at the Paducah, Kentucky, Site

International Nuclear Information System (INIS)

2003-01-01

This document is a site-specific environmental impact statement (EIS) for construction and operation of a proposed depleted uranium hexafluoride (DUF 6 ) conversion facility at the U.S. Department of Energy (DOE) Paducah site in northwestern Kentucky (Figure S-1). The proposed facility would convert the DUF 6 stored at Paducah to a more stable chemical form suitable for use or disposal. In a Notice of Intent (NOI) published in the ''Federal Register'' (FR) on September 18, 2001 (''Federal Register'', Volume 66, page 48123 [66 FR 48123]), DOE announced its intention to prepare a single EIS for a proposal to construct, operate, maintain, and decontaminate and decommission two DUF 6 conversion facilities at Portsmouth, Ohio, and Paducah, Kentucky, in accordance with the National Environmental Policy Act of 1969 (NEPA) (''United States Code'', Title 42, Section 4321 et seq. [42 USC 4321 et seq.]) and DOE's NEPA implementing procedures (''Code of Federal Regulations'', Title 10, Part 1021 [10 CFR Part 1021]). Subsequent to award of a contract to Uranium Disposition Services, LLC (hereafter referred to as UDS), Oak Ridge, Tennessee, on August 29, 2002, for design, construction, and operation of DUF 6 conversion facilities at Portsmouth and Paducah, DOE reevaluated its approach to the NEPA process and decided to prepare separate site-specific EISs. This change was announced in a ''Federal Register'' Notice of Change in NEPA Compliance Approach published on April 28, 2003 (68 FR 22368); the Notice is included as Attachment B to Appendix C of this EIS. This EIS addresses the potential environmental impacts from the construction, operation, maintenance, and decontamination and decommissioning (DandD) of the proposed conversion facility at three alternative locations within the Paducah site; from the transportation of depleted uranium conversion products to a disposal facility; and from the transportation, sale, use, or disposal of the fluoride-containing conversion products

Dynamic coating of mf/uf membranes for fouling mitigation

KAUST Repository

Tabatabai, S. Assiyeh Alizadeh

2017-01-19

A membrane system including an anti-fouling layer and a method of applying an anti-fouling layer to a membrane surface are provided. In an embodiment, the surface is a microfiltration (MF) or an ultrafiltration (UF) membrane surface. The anti-fouling layer can include a stimuli responsive layer and a dynamic protective layer applied over the stimuli responsive layer that can be a coating on a surface of the membrane. The stimuli responsive polymer layer can act as an adhesive prior to coating with the dynamic protective layer to aid in adhering the dynamic protective layer to the membrane surface. The dynamic protective layer can be formed by suitable nanoparticles that can prevent adhesion of foulants directly to the membrane surface. The stimuli responsive layer can be responsive to physio- chemical stimuli to cause a release of the stimuli responsive layer and the dynamic protective layer including foulants from the membrane.

The Effect of Perceived Privacy Breaches on Continued Technology Use and Individual Psychology: The Construct, Instrument Development, and an Application Using Internet Search Engines

Science.gov (United States)

Ahmad, Altaf

2010-01-01

This dissertation involved the development of a new construct, perceived privacy breach (PPB), to evaluate how a person perceives breaches of privacy in terms of whether they perceive any exchange of information was fair or not and how they believe it will impact people whose information has been shared. . This instrument assists researchers to…

"When the going gets tough, who keeps going?" Depletion sensitivity moderates the ego-depletion effect

NARCIS (Netherlands)

Salmon, Stefanie J.; Adriaanse, Marieke A.; De Vet, Emely; Fennis, Bob M.; De Ridder, Denise T D

2014-01-01

Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In

"When the going gets tough, who keeps going?" : Depletion sensitivity moderates the ego-depletion effect

NARCIS (Netherlands)

Salmon, Stefanie J.; Adriaanse, Marieke A.; De Vet, Emely; Fennis, Bob M.; De Ridder, Denise T. D.

2014-01-01

Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In

The modality effect of ego depletion: Auditory task modality reduces ego depletion.

Science.gov (United States)

Li, Qiong; Wang, Zhenhong

2016-08-01

An initial act of self-control that impairs subsequent acts of self-control is called ego depletion. The ego depletion phenomenon has been observed consistently. The modality effect refers to the effect of the presentation modality on the processing of stimuli. The modality effect was also robustly found in a large body of research. However, no study to date has examined the modality effects of ego depletion. This issue was addressed in the current study. In Experiment 1, after all participants completed a handgrip task, one group's participants completed a visual attention regulation task and the other group's participants completed an auditory attention regulation task, and then all participants again completed a handgrip task. The ego depletion phenomenon was observed in both the visual and the auditory attention regulation task. Moreover, participants who completed the visual task performed worse on the handgrip task than participants who completed the auditory task, which indicated that there was high ego depletion in the visual task condition. In Experiment 2, participants completed an initial task that either did or did not deplete self-control resources, and then they completed a second visual or auditory attention control task. The results indicated that depleted participants performed better on the auditory attention control task than the visual attention control task. These findings suggest that altering task modality may reduce ego depletion. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Portable load-cell based system for weighing UF6 cylinders

International Nuclear Information System (INIS)

Fainberg, A.; Gordon, D.; Dermendjiev, E.; Terrey, D.; Mitchell, R.

1982-01-01

A load-cell-based portable weighing system which is capable of verifying the weights of 2.2 tonne 30-inch UF 6 cylinders has been developed by the US National Bureau of Standards (NBS). This system weighs about 13 kg and has an attainable accuracy of about 1 kg. After an initial calibration at NBS, the system is ready for use in the field. Approximately 5 to 10 minutes are needed for assembly, and, if an overhead crane has access to all cylinders to be weighed, from 10 to 15 weighings may be performed in one hour. During the past year the system has been tested at several facilities around the world with satisfactory results and with favorable comments from the facility operators. Results of several tests are presented in this paper

Om direktørers fuldmagt på baggrund af UfR 2012.2533 H

DEFF Research Database (Denmark)

Andersen, Lennart Lynge; Schaumburg-Muller, Peer

2012-01-01

Den bemyndigelse, en adm. direktør - og den øvrige direktion - har til (bl.a.) at fastsætte løn- og ansættelsesvilkår for selskabets medarbejdere har hverken i den arbejdsretlige, selskabsretlige eller den aftaleretlige teori og praksis påkaldt sig megen opmærksomhed gennem årene. Højesterets dom...... af 2. maj 2012 (UfR 2012.2533 H) omhandler netop dette forhold, og afgørelsen må af flere grunde anses for principiel....

The Toxicity of Depleted Uranium

Directory of Open Access Journals (Sweden)

Wayne Briner

2010-01-01

Full Text Available Depleted uranium (DU is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed.

Thermal tests on UF6 containers and valves modelisation and extrapolation on real fire situations

International Nuclear Information System (INIS)

Duret, B.; Warniez, P.

1988-12-01

From realistic tests on containers or on valves, we propose a modelisation which we apply to 3 particular problems: resistance of a 48 Y containers, during a fire situation. Influence of the presence of a valve. Evaluation of a leakage through a breach, mechanically created before a fire

Semantic-less Breach Detection of Polymorphic Malware in Federated Cloud

Directory of Open Access Journals (Sweden)

Yahav Biran

2017-06-01

Full Text Available Cloud computing is one of the largest emerging utility services that is expected to grow enormously over the next decade. Many organizations are moving into hybrid cloud/hosted computing models. Single cloud service provider introduces cost and environmental challenges. Also, multi-cloud solution implemented by the Cloud tenant is suboptimal as it requires expensive adaptation costs. Cloud Federation is a useful structure for aggregating cloud based services under a single umbrella to share resources and responsibilities for the benefit of the member cloud service providers. An efficient security model is crucial for successful cloud business. However, with the advent of large scale and multi-tenant environments, the traditional perimeter boundaries along with traditional security practices are changing. Defining and securing asset and enclave boundaries is more challenging, and system perimeter boundaries are more susceptible to breach. This paper to describe security best practices for Cloud Federation. The paper also describes a tool and technique for detecting anomalous behavior in resource usage across the federation participants. This is a particularly serious issue because of the possibility of an attacker potentially gaining access to more than one CSP federation member. Specifically, this technique is developed for Cloud Federations since they have to deal with heterogeneous multi-platform environments with a diverse mixture of data and security log schema, and it has to do this in real time. A Semantic-less Breach detection system that implements a self-learning system was prototyped and resulted in up to 87% True-Positive rate with 93% True-Negative.

Automation of the Process to Obtain U F{sub 4} Powders; Ingenieria Basica para la Automatizacion del Proceso de Obtencion de Polvos de UF{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Fenocchio, A D [Instituto Balseiro, Universidad Nacional de Cuyo, Centro Atomico Bariloche, Universidad de Buenos Aires (Argentina)

2001-07-01

Here is exposed the preliminary analysis of the control system to be implemented in the Production Plant of UF{sub 4} Powders.The work has been done in the electronic laboratory.This implies, the setting of devices (PLC, Temperature Controllers, etc.) and the setting of the communications using the proper protocol.Also is shown a study about the logic for the first part of the conversion process of UF{sub 6}: the evaporation.This study is used to define the methodology to follow in a future PLC program.

Management of depleted uranium

International Nuclear Information System (INIS)

2001-01-01

Large stocks of depleted uranium have arisen as a result of enrichment operations, especially in the United States and the Russian Federation. Countries with depleted uranium stocks are interested in assessing strategies for the use and management of depleted uranium. The choice of strategy depends on several factors, including government and business policy, alternative uses available, the economic value of the material, regulatory aspects and disposal options, and international market developments in the nuclear fuel cycle. This report presents the results of a depleted uranium study conducted by an expert group organised jointly by the OECD Nuclear Energy Agency and the International Atomic Energy Agency. It contains information on current inventories of depleted uranium, potential future arisings, long term management alternatives, peaceful use options and country programmes. In addition, it explores ideas for international collaboration and identifies key issues for governments and policy makers to consider. (authors)

Security breaches: tips for assessing and limiting your risks.

Science.gov (United States)

Coons, Leeanne R

2011-01-01

As part of their compliance planning, medical practices should undergo a risk assessment to determine any vulnerability within the practice relative to security breaches. Practices should also implement safeguards to limit their risks. Such safeguards include facility access controls, information and electronic media management, use of business associate agreements, and education and enforcement. Implementation of specific policies and procedures to address security incidents is another critical step that medical practices should take as part of their security incident prevention plan. Medical practices should not only develop policies and procedures to prevent, detect, contain, and correct security violations, but should make sure that such policies and procedures are actually implemented in their everyday operations.

Law society breaches competition rules over financial regulation training for conveyancers

OpenAIRE

Johnson, D.

2017-01-01

The article considers the impact of a competition law ruling against the Law Society of England and Wales. \\ud \\ud The Law Society was found to have breached UK competition law rules in relation to its provision of anti-money laundering and mortgage fraud training courses to law firms. The Law Society made it a condition of membership of its Quality Conveyancing Scheme that all law firm members must only receive this training from the Law Society. A competing provider of legal training course...

Breach of Personal Security through Applicative use of Online Social Networks

Directory of Open Access Journals (Sweden)

Bojan Nikolovski

2013-11-01

Full Text Available Throughout this article there is an attempt to indicate the threats of potential to breach of personal security through applicative use of internet as well as applicative use of online social networks. In addition to many other ways of privacy protection applicative users of social network’s sites must take into considerations the risk of distributing private data. Through a series of actions and settings users can customize the security settings with the ultimate goal of reducing the risk of attack on their privacy.

Comparative Analysis of VERA Depletion Problems

International Nuclear Information System (INIS)

Park, Jinsu; Kim, Wonkyeong; Choi, Sooyoung; Lee, Hyunsuk; Lee, Deokjung

2016-01-01

Each code has its own solver for depletion, which can produce different depletion calculation results. In order to produce reference solutions for depletion calculation comparison, sensitivity studies should be preceded for each depletion solver. The sensitivity tests for burnup interval, number of depletion zones, and recoverable energy per fission (Q-value) were performed in this paper. For the comparison of depletion calculation results, usually the multiplication factors are compared as a function of burnup. In this study, new comparison methods have been introduced by using the number density of isotope or element, and a cumulative flux instead of burnup. In this paper, optimum depletion calculation options are determined through the sensitivity study of the burnup intervals and the number of depletion intrazones. Because the depletion using CRAM solver performs well for large burnup intervals, smaller number of burnup steps can be used to produce converged solutions. It was noted that the depletion intra-zone sensitivity is only pin-type dependent. The 1 and 10 depletion intra-zones for the normal UO2 pin and gadolinia rod, respectively, are required to obtain the reference solutions. When the optimized depletion calculation options are used, the differences of Q-values are found to be a main cause of the differences of solutions. In this paper, new comparison methods were introduced for consistent code-to-code comparisons even when different kappa libraries were used in the depletion calculations

The relationships between perceived organizational support, affective commitment, psychological contract breach, organizational citizenship behaviour and work engagement.

Science.gov (United States)

Gupta, Vishal; Agarwal, Upasna A; Khatri, Naresh

2016-11-01

This study examines the factors that mediate and moderate the relationships of perceived organizational support with work engagement and organization citizenship behaviour. Specifically, affective commitment is posited to mediate and psychological contract breach to moderate the above relationships. Nurses play a critical role in delivering exemplary health care. For nurses to perform at their best, they need to experience high engagement, which can be achieved by providing them necessary organizational support and proper working environment. Data were collected via a self-reported survey instrument. A questionnaire was administered to a random sample of 750 nurses in nine large hospitals in India during 2013-2014. Four hundred and seventy-five nurses (63%) responded to the survey. Hierarchical multiple regression was used for statistical analysis of the moderated-mediation model. Affective commitment was found to mediate the positive relationships between perceived organizational support and work outcomes (work engagement, organizational citizenship behaviour). The perception of unfulfilled expectations (psychological contract breach) was found to moderate the perceived organizational support-work outcome relationships adversely. The results of this study indicate that perceived organizational support exerts its influence on work-related outcomes and highlight the importance of taking organizational context, such as perceptions of psychological contract breach, into consideration when making sense of the influence of perceived organizational support on affective commitment, work engagement and citizenship behaviours of nurses. © 2016 John Wiley & Sons Ltd.

Thermofluid experiments for Fusion Reactor Safety. Visualization of exchange flows through breaches of a vacuum vessel in a fusion reactor under the LOVA condition

International Nuclear Information System (INIS)

Fujii, Sadao; Shibazaki, Hiroaki; Takase, Kazuyuki; Kunugi, Tomoaki.

1997-01-01

Exchange flow rates through breaches of a vacuum vessel in a fusion reactor under the LOVA (Loss of VAcuum event) conditions were measured quantitatively by using a preliminary LOVA apparatus and exchange flow patterns over the breach were visualized qualitatively by smoke. Velocity distributions in the exchange flows were predicted from the observed flow patterns by using the correlation method in the flow visualization procedures. Mean velocities calculated from the predicted velocity distributions at the outside of the breach were in good agreement with the LOVA experimental results when the exchange flow velocities were low. It was found that the present flow visualization and the image processing system might be an useful procedure to evaluate the exchange flow rates. (author)

Level 4 Milestone (M4): M41UF033201 - Review of Radiolysis of Brines on the Surface of a Waste Package

Energy Technology Data Exchange (ETDEWEB)

Sutton, Mark [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2011-08-12

This milestone report (M41UF033201) documents a literature review of relevant publications for gamma radiolysis occurring within a droplet of water on the outside of a waste package in a repository environment within the “

The legal status of UF{sub 6}-cylinder testing and licensing in Germany (and Europe)

Energy Technology Data Exchange (ETDEWEB)

Wieser, K.E. [Federal Institute for Material Research and Testing (BAM), Berlin (Germany); Tietze, A. [Bergische Universitaet - Gesamthochschule Wuppertal (Germany)

1991-12-31

New German and European transport regulations for road and rail transport of UF{sub 6}-cylinders are presented, in particular those provisions which have direct impact on the majority of cylinders used in shipments touching ADR and RID member states. First experiences and difficulties in it`s application are highlighted taking into account experiences of a for running German regulation. A summary of research efforts on the behaviour of cylinders in fire environments concludes the paper.

State Security Breach Response Laws: State-by-State Summary Table. Using Data to Improve Education: A Legal Reference Guide to Protecting Student Privacy and Data Security

Science.gov (United States)

Data Quality Campaign, 2011

2011-01-01

Under security breach response laws, businesses--and sometimes state and governmental agencies--are required to inform individuals when the security, confidentiality or integrity of their personal information has been compromised. This resource provides a state-by-state analysis of security breach response laws. [The Data Quality Campaign has…

PGDP [Paducah Gaseous Diffusion Plant]-UF6 handling, sampling, analysis and associated QC/QA and safety related procedures

International Nuclear Information System (INIS)

Harris, R.L.

1987-01-01

This document is a compilation of Paducah Gaseous Diffusion Plant procedures on UF 6 handling, sampling, and analysis, along with associated QC/QA and safety related procedures. It was assembled for transmission by the US Department of Energy to the Korean Advanced Energy Institute as a part of the US-Korea technical exchange program

Biodegradation behavior of natural organic matter (NOM) in a biological aerated filter (BAF) as a pretreatment for ultrafiltration (UF) of river water

KAUST Repository

Huang, Guocheng; Meng, Fangang; Zheng, Xing; Wang, Yuan; Wang, Zhigang; Liu, Huijun; Jekel, Martin R.

2011-01-01

In this study, biodegradation of natural organic matter (NOM) in a biological aerated filter (BAF) as pretreatment of UF treating river water was investigated. Photometric measurement, three-dimensional excitation-emission matrix (EEM) fluorescence

Reduction of UF4 to U-metal

International Nuclear Information System (INIS)

Namkung, H.; Min, B.T.; Kim, J.S.; Whang, S.C.

1982-01-01

In the second years of study for the production of the metallic uranium with reactors which can produce 1 Kg and 4 Kg U-metal, various factors on the yield of U-metal and the leaching condition for uranium recovery with nitric acid are examined. The jolter has been used for the charging with liner (MgF 2 ) while the hand-tamping method for the filling of reaction mixtures (UF 4 -Mg) in the reactor, and their average densities are 1.23g/cc and 2.90g/cc, respectively. The various effects on the yield such as magnesium excess, furnace control temperatue, charge densities of liner and reaction mixtures, have been studied but the yields of crude metal production are in the wide range from 93 % down to about 65 %. Generally, six percent magnesium excess produced higher yields than did either 2 or 10 percent excess. The leaching condition for the uranium recovery from slag are also investigated with dilute nitric acid (3-6N) as well as higher concentrated nitric acid (9.5N) but the leaching yields are same in either solution. Uranium recovery from the slag is very effective with dilute nitric acid (3N) leaching for less than one hour at 60degC. (Author)

Development of a fine and ultra-fine group cell calculation code SLAROM-UF for fast reactor analyses

International Nuclear Information System (INIS)

Hazama, Taira; Chiba, Go; Sugino, Kazuteru

2006-01-01

A cell calculation code SLAROM-UF has been developed for fast reactor analyses to produce effective cross sections with high accuracy in practical computing time, taking full advantage of fine and ultra-fine group calculation schemes. The fine group calculation covers the whole energy range in a maximum of 900-group structure. The structure is finer above 52.5 keV with a minimum lethargy width of 0.008. The ultra-fine group calculation solves the slowing down equation below 52.5 keV to treat resonance structures directly and precisely including resonance interference effects. Effective cross sections obtained in the two calculations are combined to produce effective cross sections over the entire energy range. Calculation accuracy and improvements from conventional 70-group cell calculation results were investigated through comparisons with reference values obtained with continuous energy Monte Carlo calculations. It was confirmed that SLAROM-UF reduces the difference in k-infinity from 0.15 to 0.01% for a JOYO MK-I fuel subassembly lattice cell calculation, and from - 0.21% to less than a statistical uncertainty of the reference calculation of 0.03% for a ZPPR-10A core criticality calculation. (author)

Contribution of effluent organic matter (EfOM) to ultrafiltration (UF) membrane fouling: Isolation, characterization, and fouling effect of EfOM fractions

KAUST Repository

Zheng, Xing; Khan, Muhammad; Croue, Jean-Philippe

2014-01-01

EfOM has been regarded as a major organic foulant resulting in UF membrane fouling in wastewater reclamation. To investigate fouling potential of different EfOM fractions, the present study isolated EfOM into hydrophobic neutrals (HPO-N), colloids

Electrochemical separation of uranium in the molten system LiF–NaF–KF–UF{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Korenko, M., E-mail: Michal.Korenko@savba.sk [Fluorine Chemistry Department, Nuclear Research Institute (NRI) Řež Plc., Husinec-Řež 130, CZ-250 68 (Czech Republic); Department of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 36 Bratislava (Slovakia); Straka, M.; Szatmáry, L. [Fluorine Chemistry Department, Nuclear Research Institute (NRI) Řež Plc., Husinec-Řež 130, CZ-250 68 (Czech Republic); Ambrová, M. [Institute of Inorganic Chemistry, Technology and Materials, Slovak University of Technology, Radlinského 9, SK-812 37 Bratislava (Slovakia); Uhlíř, J. [Fluorine Chemistry Department, Nuclear Research Institute (NRI) Řež Plc., Husinec-Řež 130, CZ-250 68 (Czech Republic)

2013-09-15

This article is focused on the electrochemical investigation (cyclic voltammetry and related studies) of possible reduction of U{sup 4+} ions to metal uranium in the molten system LiF–NaF–KF(eut.)–UF{sub 4} that can provide basis for the electrochemical extraction of uranium from molten salts. Two-step reduction mechanism for U{sup 4+} ions involving one electron exchange in soluble/soluble U{sup 4+}/U{sup 3+} system and three electrons exchange in the second step were found on the nickel working electrode. Both steps were found to be reversible and diffusion controlled. Based on cyclic voltammetry, the diffusion coefficients of uranium ions at 530 °C were found to be D(U{sup 4+}) = 1.64 × 10{sup −5} cm{sup 2} s{sup −1} and D(U{sup 3+}) 1.76 × 10{sup −5} cm{sup 2} s{sup −1}. Usage of the nickel spiral electrode for electrorefining of uranium showed fairly good feasibility of its extraction. However some oxidant present during the process of electrorefining caused that the solid deposits contained different uranium species such as UF{sub 3}, UO{sub 2} and K{sub 3}UO{sub 2}F{sub 5}.

Development and design of a UF6 gas pressure meter for 42 mm pipes

International Nuclear Information System (INIS)

Peters, E.; Wichers, V.A.

1995-08-01

X-ray fluorescence (XRF) has proved to be a feasible method of measuring the pressure of UF 6 -gas for enrichment verification purposes. Complications will arise under extreme conditions, such as high uranium deposit to gas ratios, pipe diameters smaller than 40 mm and pressures less than 100 Pa. This report presents an experimental analysis of the XRF method for design worst case conditions for 42 outer diameter cascade-to-header pipes and the development of a prototype measurement device. This prototype is integrated in the construction of the enrichment verification system. (orig.)

Can Cross-Listing Mitigate the Impact of an Information Security Breach Announcement on a Firm's Values?

Science.gov (United States)

Chen, Yong; Dong, Feng; Chen, Hong; Xu, Li

2016-08-01

The increase in globalization in the markets has driven firms to adopt online technologies and to cross-list their stocks. Recent studies have consistently found that the announcements of information security breaches (ISBs) are negatively associated with the market values of the announcing firms during the days surrounding the breach announcements. Given the improvement in firms’ information environments and the better protection for investors generated by cross-listing, does cross-listing help firms to reduce the negative impacts caused by their announcements of ISBs? This paper conducts an event study of 120 publicly traded firms (among which 25 cross-list and 95 do not), in order to explore the answer. The results indicate that the impact of ISB announcements on a firm's stock prices shows no difference between cross-listing firms and non-cross-listing firms. Cross-listing does not mitigate the impact of ISBs announcement on a firm's market value.

Ozone-depleting Substances (ODS)

Data.gov (United States)

U.S. Environmental Protection Agency — This site includes all of the ozone-depleting substances (ODS) recognized by the Montreal Protocol. The data include ozone depletion potentials (ODP), global warming...

COGEMA's UMF [Uranium Management Facility

International Nuclear Information System (INIS)

Lamorlette, G.; Bertrand, J.P.

1988-01-01

The French government-owned corporation, COGEMA, is responsible for the nuclear fuel cycle. This paper describes the activities at COGEMA's Pierrelatte facility, especially its Uranium Management Facility. UF6 handling and storage is described for natural, enriched, depleted, and reprocessed uranium. UF6 quality control specifications, sampling, and analysis (halocarbon and volatile fluorides, isotopic analysis, uranium assay, and impurities) are described. In addition, the paper discusses the filling and cleaning of containers and security at UMF

Educational Malpractice: Breach of Statutory Duty and Affirmative Acts of Negligence by a School District.

Science.gov (United States)

Beckham, Joseph

1979-01-01

A cause of action for educational malpractice may well receive initial judicial recognition through successfully harmonizing allegations of breach of a statutory duty of care and acts of negligence of a type and magnitude that would distinguish a student-plaintiff's injuries from others for whose benefit the statutory duty was created. (Author)

Quasi 2D hydrodynamic modelling of the flooded hinterland due to dyke breaching on the Elbe River

Directory of Open Access Journals (Sweden)

S. Huang

2007-01-01

Full Text Available In flood modeling, many 1D and 2D combination and 2D models are used to simulate diversion of water from rivers through dyke breaches into the hinterland for extreme flood events. However, these models are too demanding in data requirements and computational resources which is an important consideration when uncertainty analysis using Monte Carlo techniques is used to complement the modeling exercise. The goal of this paper is to show the development of a quasi-2D modeling approach, which still calculates the dynamic wave in 1D but the discretisation of the computational units are in 2D, allowing a better spatial representation of the flow in the hinterland due to dyke breaching without a large additional expenditure on data pre-processing and computational time. A 2D representation of the flow and velocity fields is required to model sediment and micro-pollutant transport. The model DYNHYD (1D hydrodynamics from the WASP5 modeling package was used as a basis for the simulations. The model was extended to incorporate the quasi-2D approach and a Monte-Carlo Analysis was used to conduct a flood sensitivity analysis to determine the sensitivity of parameters and boundary conditions to the resulting water flow. An extreme flood event on the Elbe River, Germany, with a possible dyke breach area was used as a test case. The results show a good similarity with those obtained from another 1D/2D modeling study.

UF6 breeder reactor power plants for electric power generation

International Nuclear Information System (INIS)

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

1976-01-01

The reactor concept analyzed is a 233 UF 6 core surrounded by a molten salt (Li 7 F, BeF 2 , ThF 4 ) blanket. Nuclear survey calculations were carried out for both spherical and cylindrical geometries. A maximum breeding ratio of 1.22 was found. Thermodynamic cycle calculations were performed for a variety of Rankine cycles. Optimization of a Rankine cycle for a gas core breeder reactor employing an intermediate heat exchanger gave a maximum efficiency of 37 percent. A conceptual design is presented along with a system layout for a 1000 MW stationary power plant. The advantages of the GCBR are as follows: (1) high efficiency, (2) simplified on-line reprocessing, (3) inherent safety considerations, (4) high breeding ratio, (5) possibility of burning all or most of the long-lived nuclear waste actinides, and (6) possibility of extrapolating the technology to higher temperatures and MHD direct conversion

Acute toxicity of the hydrolysis products of uranium hexafluoride (UF6) when inhaled by the rat and guinea pig. Final report

International Nuclear Information System (INIS)

Leach, L.J.; Gelein, R.M.; Panner, B.J.; Yulie, C.L.; Cox, C.C.; Balys, M.M.; Rolchigo, P.M.

1984-04-01

This report presents the experimental animal data base from which human health consequences may be predicted from exposures mimicing accidental discharges of uranium hexafluoride (UF 6 ) in the uranium industry. Rats or guinea pigs were exposed for two, five, or ten minutes duration to air having 0.44 g U/m 3 + 0.16 g HF/m 3 to 276.67 g U/m 3 + 94.07 g HF/m 3 . Survivors of each exposure were observed for 14 days for signs of U or HF intoxication. Selected animals were necropsied and samples of major organs were studied histopathologically. When enriched UF 6 (94 percent 235 U) was used, the urine and feces from each animal were measured daily for U content. Selected samples of urine were bioassayed in order to trace the course of renal injury during the two week postexposure period. 28 references, 51 figures, 23 tables

“When the going gets tough, who keeps going?” Depletion sensitivity moderates the ego-depletion effect

NARCIS (Netherlands)

Salmon, S.J.; Adriaanse, M.A.; Vet, de E.W.M.L.; Fennis, B.M.; Ridder, de D.T.D.

2014-01-01

Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In

"I Can Only Work So Hard Before I Burn Out." A Time Sensitive Conceptual Integration of Ideological Psychological Contract Breach, Work Effort, and Burnout.

Science.gov (United States)

Jones, Samantha K; Griep, Yannick

2018-01-01

Employees often draw meaning from personal experiences and contributions in their work, particularly when engaging in organizational activities that align with their personal identity or values. However, recent empirical findings have demonstrated how meaningful work can also have a negative effect on employee's well-being as employees feel so invested in their work, they push themselves beyond their limits resulting in strain and susceptibility to burnout. We develop a framework to understand this "double edged" role of meaningful work by drawing from ideological psychological contracts (iPCs), which are characterized by employees and their employer who are working to contribute to a shared ideology or set of values. Limited iPC research has demonstrated employees may actually work harder in response to an iPC breach. In light of these counterintuitive findings, we propose the following conceptual model to theoretically connect our understanding of iPCs, perceptions of breach, increases in work effort, and the potential "dark side" of repeated occurrences of iPC breach. We argue that time plays a central role in the unfolding process of employees' reactions to iPC breach over time. Further, we propose how perceptions of iPC breach relate to strain and, eventually, burnout. This model contributes to our understanding of the role of time in iPC development and maintenance, expands our exploration of ideology in the PC literature, and provides a framework to understanding why certain occupations are more susceptible to instances of strain and burnout. This framework has the potential to guide future employment interventions in ideology-infused organizations to help mitigate negative employee outcomes.

The Relationship between Psychological Contract Breach and Employee Deviance: The Moderating Role of Hostile Attributional Style

Science.gov (United States)

Chiu, Su-Fen; Peng, Jei-Chen

2008-01-01

This study investigated the main effects and the interaction effects of psychological contract breach and hostile attributional style on employee deviance (i.e., interpersonal deviance and organizational deviance). Data were collected from 233 employees and their supervisors in eight electronic companies in Taiwan. Results demonstrate that…

Research of heat releasing element of an active zone of gaseous nuclear reactor with pumped through nuclear fuel - uranium hexafluoride (UF6)

International Nuclear Information System (INIS)

Batyrbekov, G.; Batyrbekov, E.; Belyakova, E.; Kunakov, S.; Koltyshev, S.

1996-01-01

The purpose of the offered project is learning physics and substantiation of possibility of creation gaseous nuclear reactor with pumped through nuclear fuel-hexafluoride of uranium (Uf6).Main problems of this work are'. Determination of physic-chemical, spectral and optical properties of non-equilibrium nuclear - excited plasma of hexafluoride of uranium and its mixtures with other gases. Research of gas dynamics of laminar, non-mixing two-layer current of gases of hexafluoride of uranium and helium at availability and absence of internal energy release in hexafluoride of uranium with the purpose to determinate a possibility of isolation of hexafluoride of uranium from walls by inert helium. Creation and research of gaseous heat releasing element with pumped through fuel Uf6 in an active zone of research nuclear WWR-K reactor. Objects of a research: Non-equilibrium nuclear - excited plasma of hexafluoride of uranium and its mixtures with other gases. With use of specially created ampoules will come true in-reactor probe and spectral diagnostics of plasma. Calculations of kinetics with the account of main elementary processes proceeding in it, will be carried out. Two-layer non-mixed streams of hexafluoride of uranium and helium at availability and absence of internal energy release. Conditions of obtaining and characteristics of such streams will be investigated. Gaseous heat releasing element with pumped through fuel - Uf6 in an active zone of nuclear WWR-K reactor

2003 International High-Level Radioactive Waste Management Conference Breached Drip Shield Test and Validation of a TSPA Sub-Model

International Nuclear Information System (INIS)

Walton, Z.P.; Kam, J.T.

2002-01-01

The Engineered Barrier System (EBS) represents the system of human engineered barriers in the isolation of high-level radioactive waste in the proposed repository at Yucca Mountain. It is designed to complement and enhance the natural barriers to isolate and prevent the transport of radionuclides into the surrounding environment. The transport mechanism most frequently postulated for radionuclides is liquid water flux that has penetrated the EBS through corrosion breaches in the drip shield and waste packages (WP). A water flux-splitting model is used to predict flow through WP and drip shield breaches and is documented in the ''EBS Radionuclide Transport Abstraction''. A future revision of the ''EBS Radionuclide Transport Abstraction'' will be one component of the total system performance assessment--license application (TSPA-LA) for the Yucca Mountain repository. The flux-splitting model is conservative based on the following assumptions: (1) Drip impact occurs without a loss of water mass. (2) Dripping flux falls exactly at the crown of the drip shield as opposed to different locations on the curved surface, which will effect splashing and flow patterns. (3) The flux passing through a drip shield patch is proportional to the ratio of the length of the penetration in the axial direction to the total axial length of the drip shield. In this assumption all fluid that drips and flows from the drip shield crown toward a penetration will be collected if the axial locations of the source and patch coincide. (4) The potential for evaporation is ignored. Because of these conservatisms, the current version of the flux-splitting model is incapable of accounting for water that has been splashed from the impact location, the deviation of water paths (rivulets) from the axis of impact, and water loss due to evaporation. This paper will present the results of a series of breached drip shield tests used to collect empirical data for the initial validation and further

Suitable Penalty for Breach of Contract: AFROTC Cadets. A Research Report Submitted to the Faculty.

Science.gov (United States)

Reese, Robert D.

A legislative history of financial incentives in the Reserve Officer Training Corps gives perspective to an analysis of present law and policy concerning breach of contract for Air Force ROTC cadets. The changed environment, criticisms of the present law and policy, and the example of three other Western nations with all volunteer militaries are…

High frequency titration in non-aqueous solvents. Application to HF and UF6

International Nuclear Information System (INIS)

Neveu, Claude

1965-01-01

In this research thesis, the author first presents the main theoretical notions regarding high frequency titration, notably by studying characteristic curves, i.e. the titration meter indication with respect to conductibility. He reports the use of this method for the study of various reactions in non-aqueous medium: reaction of AlCl 3 with pyridine in acetonitrile, of AlCl 3 with HCl in tetrachloroethane and in nitromethane. He also reports the attempt of application of this method to the titration of HF in presence of UF 6 in CCl 4 as solvent, or by using F acceptors like BF 3 , PF 5 or ClF 3 as reactants [fr

Operator decision aid for breached fuel operation in liquid metal cooled nuclear reactors

International Nuclear Information System (INIS)

Gross, K.C.; Hawkins, R.E.; Nickless, W.K.

1991-01-01

The purpose of this paper is to report the development of an expert system that provides continuous assessment of the safety significance and technical specification conformance of Delayed Neutron (DN) signals during breached fuel operation. The completed expert system has been parallelized on an innovative distributed-memory network-computing system that enables the computationally intensive kernel of the expert system to run in parallel on a group of low-cost Unix workstations. 1 ref

Mass Transfer Model for a Breached Waste Package

International Nuclear Information System (INIS)

Hsu, C.; McClure, J.

2004-01-01

The degradation of waste packages, which are used for the disposal of spent nuclear fuel in the repository, can result in configurations that may increase the probability of criticality. A mass transfer model is developed for a breached waste package to account for the entrainment of insoluble particles. In combination with radionuclide decay, soluble advection, and colloidal transport, a complete mass balance of nuclides in the waste package becomes available. The entrainment equations are derived from dimensionless parameters such as drag coefficient and Reynolds number and based on the assumption that insoluble particles are subjected to buoyant force, gravitational force, and drag force only. Particle size distributions are utilized to calculate entrainment concentration along with geochemistry model abstraction to calculate soluble concentration, and colloid model abstraction to calculate colloid concentration and radionuclide sorption. Results are compared with base case geochemistry model, which only considers soluble advection loss

Pressure pulses generated by gas released from a breached fuel element

International Nuclear Information System (INIS)

Wu, T.S.

1979-01-01

In experimental measurements of liquid pressure pulses generated by rapid release of gas from breached fuel elements in a nuclear reactor, different peak pressures were observed at locations equidistant from the origin of the release. Using the model of a submerged spherical bubble with a nonstationary center, this analysis predicts not only that the peak pressure would be higher at a point in front of the advancing bubble than that at a point the same distance behind the bubble origin, but also that the pressure pulse in front of the bubble reaches its peak later than the pulse behind the origin

Ego Depletion Impairs Implicit Learning

Science.gov (United States)

Thompson, Kelsey R.; Sanchez, Daniel J.; Wesley, Abigail H.; Reber, Paul J.

2014-01-01

Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing) can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL) task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent. PMID:25275517

Ego depletion impairs implicit learning.

Directory of Open Access Journals (Sweden)

Kelsey R Thompson

Full Text Available Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent.

Ego depletion impairs implicit learning.

Science.gov (United States)

Thompson, Kelsey R; Sanchez, Daniel J; Wesley, Abigail H; Reber, Paul J

2014-01-01

Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing) can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL) task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent.

Lessons learned from a privacy breach at an academic health science centre.

Science.gov (United States)

Malonda, Jacqueline; Campbell, Janice; Crivianu-Gaita, Daniela; Freedman, Melvin H; Stevens, Polly; Laxer, Ronald M

2009-01-01

In 2007, the Hospital for Sick Children experienced a serious privacy breach when a laptop computer containing the personal health information of approximately 3,000 patients and research subjects was stolen from a physician-researcher's vehicle. This incident was reported to the information and privacy commissioner of Ontario (IPC). The IPC issued an order that required the hospital to examine and revise its policies, practices and research protocols related to the protection of personal health information and to educate staff on privacy-related matters.

Exposure to nature counteracts aggression after depletion.

Science.gov (United States)

Wang, Yan; She, Yihan; Colarelli, Stephen M; Fang, Yuan; Meng, Hui; Chen, Qiuju; Zhang, Xin; Zhu, Hongwei

2018-01-01

Acts of self-control are more likely to fail after previous exertion of self-control, known as the ego depletion effect. Research has shown that depleted participants behave more aggressively than non-depleted participants, especially after being provoked. Although exposure to nature (e.g., a walk in the park) has been predicted to replenish resources common to executive functioning and self-control, the extent to which exposure to nature may counteract the depletion effect on aggression has yet to be determined. The present study investigated the effects of exposure to nature on aggression following depletion. Aggression was measured by the intensity of noise blasts participants delivered to an ostensible opponent in a competition reaction-time task. As predicted, an interaction occurred between depletion and environmental manipulations for provoked aggression. Specifically, depleted participants behaved more aggressively in response to provocation than non-depleted participants in the urban condition. However, provoked aggression did not differ between depleted and non-depleted participants in the natural condition. Moreover, within the depletion condition, participants in the natural condition had lower levels of provoked aggression than participants in the urban condition. This study suggests that a brief period of nature exposure may restore self-control and help depleted people regain control over aggressive urges. © 2017 Wiley Periodicals, Inc.

Investigating the Role of Psychological Contract Breach on Career Success: Convergent Evidence from Two Longitudinal Studies

Science.gov (United States)

Restubog, Simon Lloyd D.; Bordia, Prashant; Bordia, Sarbari

2011-01-01

The current study extends past research by examining leader-member exchange as a mediator of the relationship between employee reports of psychological contract breach and career success. In addition, we tested a competing perspective in which we proposed that performance mediators (i.e., in-role performance and organizational citizenship…

Fluorescence from gaseous UF/sub 6/ excited by a near-UV dye laser. [Decay time,quenching rate,room temperature

Energy Technology Data Exchange (ETDEWEB)

Benetti, P [Pavia Univ. (Italy); Cubeddu, R; Sacchi, C A; Svelto, O; Zaraga, F [Politecnico di Milano (Italy)

1976-06-01

Preliminary data are reported on the visible fluorescence of gaseous UF/sub 6/ excited by a dye laser at 374 nm. A decay time of 500 ns at p = 0 and a quenching rate of 5.7 x 10/sup -12/cm/sup 3/molec/sup -1/s/sup -1/ have been measured at room temperature.

Evaluation of coverage of enriched UF6 cylinder storage lots by existing criticality accident alarms

International Nuclear Information System (INIS)

Lee, B.L. Jr.; Dobelbower, M.C.; Woollard, J.E.; Sutherland, P.J.; Tayloe, R.W. Jr.

1995-03-01

The Portsmouth Gaseous Diffusion Plant (PORTS) is leased from the US Department of Energy (DOE) by the United States Enrichment Corporation (USEC), a government corporation formed in 1993. PORTS is in transition from regulation by DOE to regulation by the Nuclear Regulatory Commission (NRC). One regulation is 10 CFR Part 76.89, which requires that criticality alarm systems be provided for the site. PORTS originally installed criticality accident alarm systems in all building for which nuclear criticality accidents were credible. Currently, however, alarm systems are not installed in the enriched uranium hexafluoride (UF 6 ) cylinder storage lots. This report analyzes and documents the extent to which enriched UF 6 cylinder storage lots at PORTS are covered by criticality detectors and alarms currently installed in adjacent buildings. Monte Carlo calculations are performed on simplified models of the cylinder storage lots and adjacent buildings. The storage lots modelled are X-745B, X-745C, X745D, X-745E, and X-745F. The criticality detectors modelled are located in building X-343, the building X-344A/X-342A complex, and portions of building X-330 (see Figures 1 and 2). These criticality detectors are those located closest to the cylinder storage lots. Results of this analysis indicate that the existing criticality detectors currently installed at PORTS are largely ineffective in detecting neutron radiation from criticality accidents in most of the cylinder storage lots at PORTS, except sometimes along portions of their peripheries

BLANCHIMENT ACCÉLÉRÉ DES ŒUFS NON FÉCONDÉS DE TRUITE ARC-EN-CIEL (ONCORHYNCHUS MYKISS SOUS L’EFFET DE SOLUTIONS SALINES EN VUE DE LEUR TRI MÉCANIQUE

Directory of Open Access Journals (Sweden)

MILLA S.

2007-01-01

Full Text Available Le blanchiment des œufs non fécondés dans les pontes de salmonidés en incubation artificielle permet leur élimination par tri mécanique. Le déclenchement de ce phénomène normalement plus ou moins tardif durant l’incubation a pu être accéléré grâce à une brève exposition des œufs à une solution de sel de mer. Les modalités et les effets de cette exposition sur les taux de mortalité et de malformations des embryons ont été testés sur des pontes de truite arc-en-ciel à divers stades de développement (140, 190 et 240 degrés*jours. Le passage durant 1 à 20 min dans une solution saline de 30 à 120 g/l a permis d’augmenter significativement le taux de blanchiment des œufs non fécondés sans affecter celui des œufs fécondés. Toutefois, par un effet mécanique, la manipulation nécessaire au traitement a entraîné une augmentation significative de la mortalité embryonnaire pour une manipulation à 140 degrés*jours et du taux de malformations larvaires pour une manipulation à 190 degrés*jours. A 240 degrés*jours, la manipulation n’a pas affecté le développement embryonnaire mais a entraîné un retard de l’éclosion de quelques heures. Cette étude offre de nouvelles perspectives pour améliorer le tri mécanique des œufs fécondés et non fécondés au cours de l’incubation chez la truite arc-en-ciel.

Criticality Safety Evaluation for 30B and 48X UF6 Cylinders for Transportation and Storage

International Nuclear Information System (INIS)

Mokhatri, Homami Zahra; Nematollahi, Mohammadreza; Kamyab, Shahabeddin

2011-01-01

30B and 48X cylinders are two standard containers have been used for transportation and storage of uranium hexafluoride with 21/2-ton and 10-ton loading capacity, respectively. For the sake of nuclear safety, the long-term safe storage and transportation of the cylinders are necessary to be concerned. Safe limits in handling and storage of 30B and 48X cylinders from the criticality safety considerations, has been investigated in this paper, by using the MCNP.4C code with ENDF/B-VI library data for the neutron cross sections. An infinite array model (with and without over pack) incorporating an internal H/U ratio of 0.088 was then developed to determine the optimal interstitial moderation. The maximum k eff value for the conditions of optimal interstitial moderation with the premise of no water leakage into the UF 6 cylinder has been shown to be 0.79209 ± 0.0011 for the 30B cylinder and 0.7625±0.0013 for 48X cylinder with 5 wt % 235 U enrichment. Based on this evaluation, the 30B and 48X UF 6 cylinders with 5 wt % 235 U enrichment meet the 10 CFR part 71 criteria for Fissile Class I packages, even in the worst case, and has a Transport Index (TI) of zero for criticality safety purposes

Remedies for Breach Under the United Nations Convention on Contracts for International Sale of Goods (CISG)

DEFF Research Database (Denmark)

Lookofsky, Joseph

2011-01-01

For every breach of a binding contract, there must be some remedy. The gap-filling remedial structure of the 1980 Vienna Sales Convention (CISG) reflects the fact that all significant forms of remedial relief may be said to fall within three basic courses of action which modern legal systems make...