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Development, Installation and Operation of the Mpc&a Operations Monitoring (Mom) System at the Joint Institute for Nuclear Research (Jinr) Dubna, Russia (open access)

Development, Installation and Operation of the Mpc&a Operations Monitoring (Mom) System at the Joint Institute for Nuclear Research (Jinr) Dubna, Russia

The Material Protection, Control and Accounting (MPC&A) Operations Monitoring (MOM) systems handling at the International Intergovernmental Organization - Joint Institute for Nuclear Research (JINR) is described in this paper. Category I nuclear material (plutonium and uranium) is used in JINR research reactors, facilities and for scientific and research activities. A monitoring system (MOM) was installed at JINR in April 2003. The system design was based on a vulnerability analysis, which took into account the specifics of the Institute. The design and installation of the MOM system was a collaborative effort between JINR, Brookhaven National Laboratory (BNL) and the U.S. Department of Energy (DOE). Financial support was provided by DOE through BNL. The installed MOM system provides facility management with additional assurance that operations involving nuclear material (NM) are correctly followed by the facility personnel. The MOM system also provides additional confidence that the MPC&A systems continue to perform effectively.
Date: July 12, 2009
Creator: Kartashov, V. V.; Pratt, W.; Romanov, Y. A.; Samoilov, V. N.; Shestakov, B. A.; Duncan, C. et al.
System: The UNT Digital Library
In-Born Radio Frequency Identification Devices for Safeguards Use at Gas-Centrifuge Enrichment Plants (open access)

In-Born Radio Frequency Identification Devices for Safeguards Use at Gas-Centrifuge Enrichment Plants

Global expansion of nuclear power has made the need for improved safeguards measures at Gas Centrifuge Enrichment Plants (GCEPs) imperative. One technology under consideration for safeguards applications is Radio Frequency Identification Devices (RFIDs). RFIDs have the potential to increase IAEA inspector"s efficiency and effectiveness either by reducing the number of inspection visits necessary or by reducing inspection effort at those visits. This study assesses the use of RFIDs as an integral component of the "Option 4" safeguards approach developed by Bruce Moran, U.S. Nuclear Regulatory Commission (NRC), for a model GCEP [1]. A previous analysis of RFIDs was conducted by Jae Jo, Brookhaven National Laboratory (BNL), which evaluated the effectiveness of an RFID tag applied by the facility operator [2]. This paper presents a similar evaluation carried out in the framework of Jo’s paper, but it is predicated on the assumption that the RFID tag is applied by the manufacturer at the birth of the cylinder, rather than by the operator. Relevant diversion scenarios are examined to determine if RFIDs increase the effectiveness and/ or efficiency of safeguards in these scenarios. Conclusions on the benefits offered to inspectors by using in-born RFID tagging are presented.
Date: July 12, 2009
Creator: Ward, R. & Rosenthal, M.
System: The UNT Digital Library
Nanosecond Mid-Infrared Detection for Pulse Radiolysis (open access)

Nanosecond Mid-Infrared Detection for Pulse Radiolysis

Pulse radiolysis, utilizing electron pulses from accelerators, is the definitive method for adding single positive or negative charges to molecules. It is also among the most effective means for creating free radicals. Such species are particularly important in applications such as redox catalysis relevant to solar energy conversion and advanced nuclear energy systems. Coupled with fast UV-visible detection, pulse radiolysis has become an extremely powerful method for monitoring the kinetics of the subsequent reactions of these species on timescales ranging from picoseconds to seconds. However, in many important contexts the radicals formed are difficult to identify due to their broad and featureless UV-visible absorption spectra. Time-resolved infrared (TRIR) absorption spectroscopy is a powerful structural probe of short-lived intermediates, which allows multiple transient species to be clearly identified and simultaneously monitored in a single process. Unfortunately, due to technical challenges the coupling of fast (sub-millisecond) TRIR with pulse radiolysis has received little attention, being confined to gas-phase studies. Taking advantage of recent developments in mid-IR laser technology, we have recently begun developing nanosecond TRIR detection methodologies for condensed-phase samples at our Laser Electron Accelerator Facility (LEAF). The results of preliminary pulse radiolysis-TRIR investigations on the formation of the one-electron reduced forms …
Date: July 12, 2009
Creator: Grills, D. C.; Preses, J. M.; Wishart, J. F. & Cook, A. R.
System: The UNT Digital Library
Next Generation Safeguards Initiative Workshop on Enhanced Recruiting for International Safeguards (open access)

Next Generation Safeguards Initiative Workshop on Enhanced Recruiting for International Safeguards

Brookhaven National Laboratory (BNL) hosted a Workshop on Enhanced Recruiting for International Safeguards October 22 and 23, 2008. The workshop was sponsored by DOE/NA-243 under the Next Generation Safeguards Initiative (NGSI). Placing well-qualified Americans in sufficient number and in key safeguards positions within the International Atomic Energy Agency’s (IAEA’s) Department of Safeguards is an important U.S. non-proliferation objective. The goal of the NGSI Workshop on Enhanced Recruiting for International Safeguards was to improve U.S. efforts to recruit U.S. citizens for IAEA positions in the Department of Safeguards. The participants considered the specific challenges of recruiting professional staff, safeguards inspectors, and managers. BNL’s International Safeguards Project Office invited participants from the U.S. Department of Energy, the IAEA, U.S. national laboratories, private industry, academia, and professional societies who are either experts in international safeguards or who understand the challenges of recruiting for technical positions. A final report for the workshop will be finalized and distributed in early 2009. The main finding of the workshop was the need for an integrated recruitment plan to take into account pools of potential candidates, various government and private agency stakeholders, the needs of the IAEA, and the NGSI human capital development plan. There were numerous findings …
Date: July 12, 2009
Creator: Pepper, S. E.; Rosenthal, M. D.; Fishbone, L. G.; Occhogrosso, D. M.; Lockwood, D.; Carroll, C. J. et al.
System: The UNT Digital Library
Non-Proliferative, Thorium-Based, Core and Fuel Cycle for Pressurized Water Reactors (open access)

Non-Proliferative, Thorium-Based, Core and Fuel Cycle for Pressurized Water Reactors

Two of the major barriers to the expansion of worldwide adoption of nuclear power are related to proliferation potential of the nuclear fuel cycle and issues associated with the final disposal of spent fuel. The Radkowsky Thorium Fuel (RTF) concept proposed by Professor A. Radkowsky offers a partial solution to these problems. The main idea of the concept is the utilization of the seed-blanket unit (SBU) fuel assembly geometry which is a direct replacement for a 'conventional' assembly in either a Russian pressurized water reactor (VVER-1000) or a Western pressurized water reactor (PWR). The seed-blanket fuel assembly consists of a fissile (U) zone, known as seed, and a fertile (Th) zone known as blanket. The separation of fissile and fertile allows separate fuel management schemes for the thorium part of the fuel (a subcritical 'blanket') and the 'driving' part of the core (a supercritical 'seed'). The design objective for the blanket is an efficient generation and in-situ fissioning of the U233 isotope, while the design objective for the seed is to supply neutrons to the blanket in a most economic way, i.e. with minimal investment of natural uranium. The introduction of thorium as a fertile component in the nuclear fuel …
Date: July 12, 2009
Creator: M., Todosow; M., Todosow & Raitses, G. (BNL) Galperin, A. (Ben Gurion University)
System: The UNT Digital Library
Proliferation Risk Reduction Study of Alternative Spent Fuel Processing (open access)

Proliferation Risk Reduction Study of Alternative Spent Fuel Processing

This paper presents the results of an evaluation of the relative proliferation risks of particular reprocessing technologies focusing on COEX, UREX+, and pyroprocessing
Date: July 12, 2009
Creator: Bari, R. A.; Phillips, J.; Pilat, J.; Rochau, G.; Therios, I.; Wigeland, R. et al.
System: The UNT Digital Library
Ionic Liquid Membranes for Carbon Dioxide Separation (open access)

Ionic Liquid Membranes for Carbon Dioxide Separation

Recent scientific studies are rapidly advancing novel technological improvements and engineering developments that demonstrate the ability to minimize, eliminate, or facilitate the removal of various contaminants and green house gas emissions in power generation. The Integrated Gasification Combined Cycle (IGCC) shows promise for carbon dioxide mitigation not only because of its higher efficiency as compared to conventional coal firing plants, but also due to a higher driving force in the form of high partial pressure. One of the novel technological concepts currently being developed and investigated is membranes for carbon dioxide (CO2) separation, due to simplicity and ease of scaling. A challenge in using membranes for CO2 capture in IGCC is the possibility of failure at elevated temperatures or pressures. Our earlier research studies examined the use of ionic liquids on various supports for CO2 separation over the temperature range, 37°C-300°C. The ionic liquid, 1-hexyl-3methylimidazolium Bis(trifluoromethylsulfonyl)imide, ([hmim][Tf2N]), was chosen for our initial studies with the following supports: polysulfone (PSF), poly(ether sulfone) (PES), and cross-linked nylon. The PSF and PES supports had similar performance at room temperature, but increasing temperature caused the supported membranes to fail. The ionic liquid with the PES support greatly affected the glass transition temperature, while with …
Date: July 12, 2008
Creator: Myers, Christina R.; Ilconich, Jeffery B.; Luebke, David R. & Pennline, Henry W.
System: The UNT Digital Library
ANOLE Portable Radiation Detection System Field Test and Evaluation Campaign (open access)

ANOLE Portable Radiation Detection System Field Test and Evaluation Campaign

Handheld, backpack, and mobile sensors are elements of the Global Nuclear Detection System for the interdiction and control of illicit radiological and nuclear materials. They are used by the U.S. Department of Homeland Security (DHS) and other government agencies and organizations in various roles for border protection, law enforcement, and nonproliferation monitoring. In order to systematically document the operational performance of the common commercial off-the-shelf portable radiation detection systems, the DHS Domestic Nuclear Detection Office conducted a test and evaluation campaign conducted at the Nevada Test Site from January 18 to February 27, 2006. Named “Anole,” it was the first test of its kind in terms of technical design and test complexities. The Anole test results offer users information for selecting appropriate mission-specific portable radiation detection systems. The campaign also offered manufacturers the opportunity to submit their equipment for independent operationally relevant testing to subsequently improve their detector performance. This paper will present the design, execution, and methodologies of the DHS Anole portable radiation detection system test campaign.
Date: July 12, 2007
Creator: Hodge, Chris A.
System: The UNT Digital Library
Defect-Induced Photoconductivity in Layered Manganese Oxides: ADensity Functional Theory Study (open access)

Defect-Induced Photoconductivity in Layered Manganese Oxides: ADensity Functional Theory Study

None
Date: July 12, 2007
Creator: Kwon, Kideok D.; Refson, Keith & Sposito, Garrison
System: The UNT Digital Library
Hollow Waveguide Gas Sensor for Mid-Infrared Trace Gas Analysis (open access)

Hollow Waveguide Gas Sensor for Mid-Infrared Trace Gas Analysis

A hollow waveguide mid-infrared gas sensor operating from 1000 cm{sup -1} to 4000 cm{sup -1} has been developed, optimized, and its performance characterized by combining a FT-IR spectrometer with Ag/Ag-halide hollow core optical fibers. The hollow core waveguide simultaneously serves as a light guide and miniature gas cell. CH{sub 4} was used as test analyte during exponential dilution experiments for accurate determination of the achievable limit of detection (LOD). It is shown that the optimized integration of an optical gas sensor module with FT-IR spectroscopy provides trace sensitivity at the few hundreds of parts-per-billion concentration range (ppb, v/v) for CH{sub 4}.
Date: July 12, 2007
Creator: Kim, S.; Young, C.; Chan, J.; Carter, C. & Mizaikoff, B.
System: The UNT Digital Library
Precise predictions for B -> Xs l+ l- in the large q2 region (open access)

Precise predictions for B -> Xs l+ l- in the large q2 region

The inclusive B -> Xs l+ l- decay rate in the large q2 region (q2> m_psi'2) receives significant nonperturbative corrections. The resulting uncertainties can be drastically reduced by normalizing the rate to the B -> Xu l nu rate with the same q2 cut, which allows for much improved tests of short distance physics. We calculate this ratio, including the order 1/m_b3 nonperturbative corrections and the analytically known NNLO perturbative corrections. Since in the large q2 region an inclusive measurement may be feasible via a sum over exclusive states, our results could be useful for measurements at LHCb and possibly for studies of B -> Xd l+ l-.
Date: July 12, 2007
Creator: Ligeti, Zoltan; Ligeti, Zoltan & Tackmann, Frank J.
System: The UNT Digital Library
Proceedings of the Plutonium Futures ? The Science 2006 Conference (open access)

Proceedings of the Plutonium Futures ? The Science 2006 Conference

Plutonium Futures--The Science 2006 provided opportunities to examine present knowledge of the chemical and physical properties of plutonium and other actinides in complex media and materials; to discuss the current and emerging science (chemistry, physics, materials science, nuclear science, and environmental effects) of plutonium and actinides relevant to enhancing global nuclear security; and to exchange ideas. This international conference also provided a forum for illustrating and enhancing capabilities and interests, and assessing issues in these areas. U.S. and international scientists, engineers, faculty, and students from universities, national laboratories, and DOE's nuclear complex were encouraged to participate and make technical contributions. The Conference ran from Sunday, July 9th through Thursday, July 13th. A popular aspect of the conference was the opening tutorial session on Sunday afternoon intended for students and scientists new to the area of plutonium research. The tutorial was well attended by novices and veterans alike, and featured such diverse topics as; plutonium metallurgy, plutonium in the environment, and international arms control and nonproliferation. Two plenary lectures began each morning and each afternoon session and highlighted the breakout sessions on coordination/organometallic chemistry, solid-state physics, environmental chemistry, materials science, separations and reprocessing, advanced fuels and waste forms, phase transformations, solution …
Date: July 12, 2007
Creator: Fluss, M; Hobart, D; Allan, P & Jarvinen, G
System: The UNT Digital Library
THERMAL AND SPECTROSCOPIC ANALYSES OF CAUSTIC LIDE SOLVENT EXTRACTION SOLVENT CONTACTED WITH 16 MOLAR AND 8 MOLAR NITRIC ACID (open access)

THERMAL AND SPECTROSCOPIC ANALYSES OF CAUSTIC LIDE SOLVENT EXTRACTION SOLVENT CONTACTED WITH 16 MOLAR AND 8 MOLAR NITRIC ACID

Thermal and spectroscopic analyses were performed on multiple layers formed from contacting Caustic Side Solvent Extraction (CSSX) solvent with 1 M or 3 M nitric acid. A slow chemical reaction occurs (i.e., over several weeks) between the solvent and 1 M or 3 M nitric acid as evidenced by color changes and the detection of nitro groups in the infrared spectrum of the aged samples. Thermal analysis revealed that decomposition of the resulting mixture does not meet the definition of explosive or deflagrating material.
Date: July 12, 2007
Creator: Fondeur, F; David Hobbs, D & Samuel Fink, S
System: The UNT Digital Library
The 2mrad Crossing Angle Interaction Region and Extraction Line (open access)

The 2mrad Crossing Angle Interaction Region and Extraction Line

A complete optics design for the 2mrad crossing angle interaction region and extraction line was presented at Snowmass 2005. Since this time, the design task force has been working on developing and improving the performance of the extraction line. The work has focused on optimizing the final doublet parameters and on reducing the power losses resulting from the disrupted beam transport. In this paper, the most recent status of the 2mrad layout and the corresponding performance are presented.
Date: July 12, 2006
Creator: Appleby, R.; U., Manchester; Angal-Kalinin, D.; Tech, /Cockcroft Inst. Accel. Sci.; Dadoun, O.; Bambade, P. et al.
System: The UNT Digital Library
Accurate Enthalpies of Formation of Alkali and Alkaline Earth Metal Oxides and Hydroxides: Assessment of the Correlation Consistent Composite Approach (ccCA) (open access)

Accurate Enthalpies of Formation of Alkali and Alkaline Earth Metal Oxides and Hydroxides: Assessment of the Correlation Consistent Composite Approach (ccCA)

Article on accurate enthalpies of formation of alkali and alkaline earth metal oxides and hydroxides and an assessment of the correlation consistent composite approach (ccCA).
Date: July 12, 2006
Creator: Ho, Dustin S.; DeYonker, Nathan J.; Cundari, Thomas R., 1964- & Wilson, Angela K.
System: The UNT Digital Library
Air convection noise of pencil-beam interferometer for long traceprofiler (open access)

Air convection noise of pencil-beam interferometer for long traceprofiler

In this work, we investigate the effect of air convection onlaser-beam pointing noise essential for the long trace profiler (LTP). Wedescribe this pointing error with noise power density (NPD) frequencydistributions. It is shown that the NPD spectra due to air convectionhave a very characteristic form. In the range of frequencies from ~;0.05Hz to ~;0.5 Hz, the spectra can be modeled with an inverse-power-lawfunction. Depending on the intensity of air convection that is controlledwith a resistive heater of 100 to 150 mW along a one-meter-long opticalpath, the power index lies between 2 and 3 at an overall rms noise of~;0.5 to 1 microradian. The efficiency of suppression of the convectionnoise by blowing air across the beam optical path is also discussed.Air-blowing leads to a white-noise-like spectrum. Air blowing was appliedto the reference channel of an LTP allowing demonstration of thecontribution of air convection noise to the LTP reference beam. Theability to change (with the blowing technique presented) the spectralcharacteristics of the beam pointing noise due to air convection allowsone to investigate the contribution of the convection effect, and thusmake corrections to the power spectral density spectra measured with theLTP.
Date: July 12, 2006
Creator: Yashchuk, Valeriy V.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R. & Takacs, Peter Z.
System: The UNT Digital Library
Design of an Interaction Region with Head-On Collisions for the ILC (open access)

Design of an Interaction Region with Head-On Collisions for the ILC

An interaction region (IR) with head-on collisions is considered as an alternative to the baseline configuration of the International Linear Collider (ILC) which includes two IRs with finite crossing-angles (2 and 20 mrad). Although more challenging for the beam extraction, the head-on scheme is favored by the experiments because it allows a more convenient detector configuration, particularly in the forward region. The optics of the head-on extraction is revisited by separating the e+ and e- beams horizontally, first by electrostatic separators operated at their LEP nominal field and then using a defocusing quadrupole of the final focus beam line. In this way the septum magnet is protected from the beamstrahlung power. Newly optimized final focus and extraction optics are presented, including a first look at post-collision diagnostics. The influence of parasitic collisions is shown to lead to a region of stable collision parameters. Disrupted beam and beamstrahlung photon losses are calculated along the extraction elements.
Date: July 12, 2006
Creator: Appleby, R.; U., /Cockcroft Inst. Accel. Sci. Tech. /Manchester; Angal-Kalinin, D.; Jackson, F.; /Daresbury; Alabau-Pons, M . et al.
System: The UNT Digital Library
Positioning Errors of Pencil-beam Interferometers for Long TraceProfilers (open access)

Positioning Errors of Pencil-beam Interferometers for Long TraceProfilers

We analyze the random noise and the systematic errors of the positioning of the interference patterns in the long trace profilers (LTP). The analysis, based on linear regression methods, allows the estimation of the contributions to the positioning error of a number of effects, including non-uniformity of the detector photo-response and pixel pitch, read-out and dark signal noise, ADC resolution, as well as signal shot noise. The dependence of the contributions on pixel size and on total number of pixels involved in positioning is derived analytically. The analysis, when applied to the LTP II available at the ALS optical metrology laboratory, has shown that the main source for the random positioning error of the interference pattern is the read-out noise estimated to be {approx}0.2 rad. The photo-diode-array photo-response and pixel pitch non-uniformity determine the magnitude of the systematic positioning error and are found to be {approx}0.3 rad for each of the effects. Recommendations for an optimal fitting strategy, detector selection and calibration are provided. Following these recommendations will allow the reduction of the error of LTP interference pattern positioning to a level adequate for the slope measurement with 0.1-rad accuracy.
Date: July 12, 2006
Creator: Yashchuk, Valeriy V.
System: The UNT Digital Library
Simulation of the ILC Collimation System using BDSIM, MARS15 and STRUCT (open access)

Simulation of the ILC Collimation System using BDSIM, MARS15 and STRUCT

None
Date: July 12, 2006
Creator: Carter, J.; Agapov, I.; Blair, G. A.; Deacon, L.; Drozhdin, A. I.; Mokhov, N. V. et al.
System: The UNT Digital Library
Simulation of the ILC Collimation System using BDSIM, MARS15 and STRUCT (open access)

Simulation of the ILC Collimation System using BDSIM, MARS15 and STRUCT

The simulation codes BDSIM, MARS15 and STRUCT are used to simulate in detail the collimation section of the International Linear Collider (ILC). A comparative study of the collimation system performance for the 250 x 250 GeV machine is conducted, and the key radiation loads are calculated. Results for the latest ILC designs are presented together with their implications for future design iterations.
Date: July 12, 2006
Creator: Carter, J.; Agapov, I.; Blair, G. A.; Deacon, L.; Drozhdin, A.I.; Mokhov, N. V. et al.
System: The UNT Digital Library
SRNL Emergency Response Capability for Atmospheric Contaminant Releases (open access)

SRNL Emergency Response Capability for Atmospheric Contaminant Releases

Emergency response to an atmospheric release of chemical or radiological contamination is enhanced when plume predictions, field measurements, and real-time weather information are integrated into a geospatial framework. The Weather Information and Display (WIND) System at Savannah River National Laboratory (SRNL) utilizes such an integrated framework. The rapid availability of predictions from a suite of atmospheric transport models within this geospatial framework has proven to be of great value to decision makers during an emergency involving an atmospheric contaminant release.
Date: July 12, 2006
Creator: Koffman, L.; Chuck Hunter, C.; Robert Buckley, R. & Robert Addis, R.
System: The UNT Digital Library
E-Beam Driven Accelerators: Working Group Summary (open access)

E-Beam Driven Accelerators: Working Group Summary

The working group has identified the parameters of an afterburner based on the design of a future linear collider. The new design brings the center of mass energy of the collider from 1 to 2 TeV. The afterburner is located in the final focus section of the collider, operates at a gradient of {approx}4 GeV/m, and is only about 125 m long. Very important issues remain to be addressed, and include the physics and design of the positron side of the afterburner, as well as of the final focus system. Present plasma wakefield accelerator experiments have reached a level of maturity and of relevance to the afterburner, that make it timely to involve the high energy physics and accelerator community in the afterburner design process. The main result of this working group is the first integration of the designs of a future linear collider and an afterburner.
Date: July 12, 2005
Creator: Muggli, P.; U., /Southern California & Ng, J.S.T.
System: The UNT Digital Library
CIRCE, the Proposed Coherent Infrared Center at the LawrenceBerkeley National Laboratory (open access)

CIRCE, the Proposed Coherent Infrared Center at the LawrenceBerkeley National Laboratory

At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory (LBNL), we are proposing the construction of CIRCE (Coherent InfraRed Center), a ring-based photon source completely optimized for the generation of coherent synchrotron radiation (CSR) in the terahertz frequency range [1]. CIRCE exploits the full complement of the CSR-production mechanisms presently available for obtaining top performance, including a photon flux exceeding by more than nine orders of magnitude that of existing ''conventional'' broadband terahertz sources.
Date: July 12, 2005
Creator: Byrd, John M.; Martin, Michael M. & Sannibale, Fernando
System: The UNT Digital Library
A Combined Experimental and Computational Approach for the Design of Mold Topography that Leads to Desired Ingot Surface and Microstructure in Aluminum Casting. (open access)

A Combined Experimental and Computational Approach for the Design of Mold Topography that Leads to Desired Ingot Surface and Microstructure in Aluminum Casting.

A method combining features of front-tracking methods and fixed-domain methods is presented to model dendritic solidification of pure materials. To explicitly track the interface growth and shape of the solidifying crystals, a fronttracking approach based on the level set method is implemented. To easily model the heat and momentum transport, a fixed-domain method is implemented assuming a diffused freezing front where the liquid fraction is defined in terms of the level set function. The fixed-domain approach, by avoiding the explicit application of essential boundary conditions on the freezing front, leads to an energy conserving methodology that is not sensitive to the mesh size. To compute the freezing front morphology, an extended Stefan condition is considered. Applications to several classical Stefan problems and two- and three-dimensional crystal growth of pure materials in an undercooled melt including the effects of melt flow are considered. The computed results agree very well with available analytical solutions as well as with results obtained using front-tracking techniques and the phase-field method.
Date: July 12, 2005
Creator: Dr. Zabaras, N. & Tan, L.
System: The UNT Digital Library