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 Decade: 2000-2009
Summary of operations and performance of the Murdock site restoration project in 2008.

Summary of operations and performance of the Murdock site restoration project in 2008.

Date: June 4, 2009
Creator: LaFreniere, L. M. & Division, Environmental Science
Description: This document summarizes the performance of the groundwater and surface water restoration systems installed by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) at the former CCC/USDA grain storage facility in Murdock, Nebraska, during the third full year of system operation, from January 1 through December 31, 2008. Performance in June 2005 through December 2007 was reported previously (Argonne 2007, 2008). In the Murdock project, several innovative technologies are being used to remove carbon tetrachloride contamination from a shallow aquifer underlying the town, as well as from water naturally discharged to the surface at the headwaters of a small creek (a tributary to Pawnee Creek) north of the town (Figure 1.1). The restoration activities at Murdock are being conducted by the CCC/USDA as a non-time-critical removal action under the regulatory authority and supervision of the U.S. Environmental Protection Agency (EPA), Region VII. Argonne National Laboratory assisted the CCC/USDA by providing technical oversight for the restoration effort and facilities during this review period. Included in this report are the results of all sampling and monitoring activities performed in accord with the EPA-approved Monitoring Plan for this site (Argonne 2006), as well as additional investigative activities conducted during the ...
Contributing Partner: UNT Libraries Government Documents Department
Grain refinement in beryllium by equal channel angular extrusion.

Grain refinement in beryllium by equal channel angular extrusion.

Date: January 1, 2003
Creator: Alexander, D. J. (David J.); Mauro, M. E. (Michael Ernest); Cooley, J. C. (Jason C.) & Dauelsberg, L. B. (Lawrence B.)
Description: Ultrafine-grained Be is the material of choice for fabrication of the NIF target capsules. One method of producing ultrafine grains in metals is by imposing very large strains. Equal channel angular extrusion (ECAE) has been used to achieve these high strains. Previous work has shown that powder-source Be can be successfully processed by ECAE. Pure Be and Be-0.9 at% Cu alleys have been arc melted and cast into billets 5 mm in diameter by 30 mm in length. These billets were enclosed in cans fabricated from commercial purity Ni, with an electron-beam welded end plug. These cans were extruded at 425C in ECAE tooling with a 120' angle between the inlet and outlet channels. The billets were extruded up to 4 times. The microstructures of the powdersource Be and the arc-melted Be and Be-0.9 at% Cu materials will be presented, and the effects of the ECAE processing on the grain size will be discussed.
Contributing Partner: UNT Libraries Government Documents Department
A Comparison of Proliferation Resistance Measures of Misuse Scenarios Using a Markov Approach

A Comparison of Proliferation Resistance Measures of Misuse Scenarios Using a Markov Approach

Date: May 11, 2008
Creator: Yue,M.; Cheng, L.-Y. & Bari, R.
Description: Misuse of declared nuclear facilities is one of the important proliferation threats. The robustness of a facility against these threats is characterized by a number of proliferation resistance (PR) measures. This paper evaluates and compares PR measures for several misuse scenarios using a Markov model approach to implement the pathway analysis methodology being developed by the PR&PP (Proliferation Resistance and Physical Protection) Expert Group. Different misue strategies can be adopted by a proliferator and each strategy is expected to have different impacts on the proliferator's success. Selected as the probabilistic measure to represent proliferation resistance, the probabilities of the proliferator's success of misusing a hypothetical ESFR (Example Sodium Fast Reactor) facility system are calculated using the Markov model based on the pathways constructed for individual misuse scenarios. Insights from a comparison of strategies that are likely to be adopted by the proliferator are discussed in this paper.
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Coyotes in the East: Are they impacting deer?

Coyotes in the East: Are they impacting deer?

Date: April 1, 2009
Creator: Kilgo, John,C.
Description: A brief article on the impact of coyotes to deer populations.
Contributing Partner: UNT Libraries Government Documents Department
Closure Report for Corrective Action Unit 107: Low Impact Soil Sites, Nevada Test Site, Nevada

Closure Report for Corrective Action Unit 107: Low Impact Soil Sites, Nevada Test Site, Nevada

Date: June 1, 2009
Creator: Restoration, NSTec Environmental
Description: Corrective Action Unit (CAU) 107 is identified in the Federal Facility Agreement and Consent Order (FFACO) as 'Low Impact Soil Sites' and consists of the following 15 Corrective Action Sites (CASs), located in Areas 1, 2, 3, 4, 5, 9, 10, and 18 of the Nevada Test Site: CAS 01-23-02, Atmospheric Test Site - High Alt; CAS 02-23-02, Contaminated Areas (2); CAS 02-23-03, Contaminated Berm; CAS 02-23-10, Gourd-Amber Contamination Area; CAS 02-23-11, Sappho Contamination Area; CAS 02-23-12, Scuttle Contamination Area; CAS 03-23-24, Seaweed B Contamination Area; CAS 03-23-27, Adze Contamination Area; CAS 03-23-28, Manzanas Contamination Area; CAS 03-23-29, Truchas-Chamisal Contamination Area; CAS 04-23-02, Atmospheric Test Site T4-a; CAS 05-23-06, Atmospheric Test Site; CAS 09-23-06, Mound of Contaminated Soil; CAS 10-23-04, Atmospheric Test Site M-10; and CAS 18-23-02, U-18d Crater (Sulky). Closure activities were conducted from February through April 2009 according to the FFACO (1996; as amended February 2008) and Revision 1 of the Streamlined Approach for Environmental Restoration Plan for CAU 107 (U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, 2009). The corrective action alternatives included No Further Action and Closure in Place with Administrative Controls. Closure activities are summarized.
Contributing Partner: UNT Libraries Government Documents Department
Multi Module Modeling of Ultra-Relativistic Heavy Ion Collisions.

Multi Module Modeling of Ultra-Relativistic Heavy Ion Collisions.

Date: January 1, 2002
Creator: Magas, V. K.; Csernai, L. P. (László P.); Keranen, A.; Manninen, J. & Strottman, D. D. (Daniel D.)
Description: Multi Module Model is required for the realistic and detailed description of an ultrarelativistic heavy ion reaction. We are working in the framework of such a model: initial stages are described by Effective String Rope Model with expanding final streaks; hydrodynamical approach is used for the intermediate stages. This paper is mainly devoted to Third Module - the one dealing with Freeze Out (FO). Two possibilities are discussed in details: (A) freeze out at the constant time hypersurface, where the statistical production model is used to describe post FO particle species; and (B) simultaneous hadronization and freeze out from supercooled QGP. For the last case the ALCOR-like algorithm for calculation of the post FO particle species is presented, due to the fact that these do not have time to reach chemical equilibrium.
Contributing Partner: UNT Libraries Government Documents Department
Proposed technologies for use in the National TRU waste system optimization.

Proposed technologies for use in the National TRU waste system optimization.

Date: January 1, 2002
Creator: Moody, D. C. (David C.); Lott, S. A. (Sheila A.); Behrens, R. G. (Robert G.); Basabilvazo, George T. (George Taylor), & Countiss, S. (Sue)
Description: Technology deployments planned for the National TRU Waste System Optimization Project are aimed at using appropriate cost-effective technologies to drive the national TRU waste system to a performance-driven certification system that is based on administrative and operational requirements with a sound safety and/or technical basis. Appropriate technology deployments are determined by first identifying technology needs; selecting promising technologies; and overseeing the development of operating procedures, personnel training, testing, and startup and operations to ensure that the resulting operations function correctly and meet the TRU waste certification requirements.
Contributing Partner: UNT Libraries Government Documents Department
Conveyorized Photoresist Stripping Replacement for Flex Circuit Fabrication

Conveyorized Photoresist Stripping Replacement for Flex Circuit Fabrication

Date: February 24, 2009
Creator: Donahue, Megan
Description: A replacement conveyorized photoresist stripping system was characterized to replace the ASI photoresist stripping system. This system uses the qualified ADF-25c chemistry for the fabrication of flex circuits, while the ASI uses the qualified potassium hydroxide chemistry. The stripping process removes photoresist, which is used to protect the copper traces being formed during the etch process.
Contributing Partner: UNT Libraries Government Documents Department
Renormalization constants using quark states in fixed gauge

Renormalization constants using quark states in fixed gauge

Date: January 1, 2001
Creator: Bhattacharya, Tanmoy & Gupta, Rajan
Description: The authors present a status report on the calculation of the renormalization constants for the quark bilinears in quenched O(a) improved Wilson theory at {beta} = 6.4 using quark states in Landau gauge.
Contributing Partner: UNT Libraries Government Documents Department
NON-DESTRUCTIVE ASSAY OF CE-144 IN PRESENCE OF TRANSURANIC WASTE

NON-DESTRUCTIVE ASSAY OF CE-144 IN PRESENCE OF TRANSURANIC WASTE

Date: January 1, 2001
Creator: Laboratory, Los Alamos National
Description: The Ce- 144 isotope has been identified as a radionuclide produced in certain Los Alamos National Laboratory plutonium waste streams and thus may need to be quantified when present in reportable quantities for shipment to the Waste Isolation Pilot Plant (WIPP). The most intense gamma ray from Ce-144 was found to be the 133.53 keV peak. At this energy, there were no interfering plutonium or plutonium daughter gainma rays. Furthermore, it was determined that there were no interferences produced by Ce- 144 or its progenies that could degrade the plutonium isotopic analysis. At 5% of the total activity per gram of plutonium, the reportable limit, the Ce-144 peak at 133.53 keV will remain above the primary plutonium peak (129.3 keV) for approximately 7 years and remain quantifiable for at least 12 to 13 years from the time the isotope was chemically separated. It is therefore concluded that Ce-144 will be quantifiable whenever it exceeds 5% of the total activity per gram of plutonium, and will not interfere with the non-destructive assay of plutonium isotopic compositions.
Contributing Partner: UNT Libraries Government Documents Department
Steering magnet design for a limited space

Steering magnet design for a limited space

Date: May 4, 2009
Creator: Okamura,M.; Fite, J.; Lodestro, V.; Raparia, D. & Ritter, J.
Description: We compare two extreme designs of steering magnets. The first one is a very thin steering magnet design which occupies only 6 mm in length and can be additionally installed as needed. The other is realized by applying extra coil windings to a quadrupole magnet and does not consume any length. The properties and the features of these steering magnets are discussed.
Contributing Partner: UNT Libraries Government Documents Department
The influence of structural defects on intragranular critical currents of bulk MgB[sub 2].

The influence of structural defects on intragranular critical currents of bulk MgB[sub 2].

Date: January 1, 2002
Creator: Serquis, A. (Adriana); Liao, Xiaozhou; Civale, L. (Leonardo); Zhu, Y. T. (Yuntian Theodore); Coulter, J. Y. (James Y.); Peterson, D. E. (Dean E.) et al.
Description: Bulk MgB2 samples were prepared under different synthesis conditions and analyzed by scanning and transmission electron microscopy. The critical current densities were determined from the magnetization versus magnetic field curves of bulk and powder-dispersed-in-epoxy samples. Results show that through a slow cooling process, the oxygen dissolved in bulk MgB2 at high synthesis temperatures can segregate and form nanometer-sized coherent precipitates of Mg(B,O)2 in the MgB2 matrix. Magnetization measurements indicate that these precipitates act as effective flux pinning centers and therefore significantly improve the intra-grain critical current density and its field dependence.
Contributing Partner: UNT Libraries Government Documents Department
Direct FuelCell/Turbine Power Plant

Direct FuelCell/Turbine Power Plant

Date: September 30, 2008
Creator: Ghezel-Ayagh, Hossein
Description: This report summarizes the progress made in development of Direct FuelCell/Turbine (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T system employs an indirectly heated Turbine Generator to supplement fuel cell generated power. The concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, minimal emissions, reduced carbon dioxide release to the environment, simplicity in design, direct reforming internal to the fuel cell, and potential cost competitiveness with existing combined cycle power plants. Proof-of-concept tests using a sub-MW-class DFC/T power plant at FuelCell Energy's (FCE) Danbury facility were conducted to validate the feasibility of the concept and to measure its potential for electric power production. A 400 kW-class power plant test facility was designed and retrofitted to conduct the tests. The initial series of tests involved integration of a full-size (250 kW) Direct FuelCell stack with a 30 kW Capstone microturbine. The operational aspects of the hybrid system in relation to the integration of the microturbine with the fuel cell, process flow and thermal balances, and control strategies for power ...
Contributing Partner: UNT Libraries Government Documents Department
The mechanical design of a proton microscope for radiography at 800 MeV

The mechanical design of a proton microscope for radiography at 800 MeV

Date: January 1, 2003
Creator: Valdiviez, R. (Robert); Sigler, F. E. (Floyd E.); Barlow, D. B. (David B.); Blind, B. (Barbara); Jason, A. J. (Andrew J.); Mottershead, C. T. et al.
Description: A proton microscope has been developed for radiography applications using the 800-MeV linear accelerator at the Los Alamos Neutron Science Center (LANSCE). The microscope provides a magnified image of a static device, or of a dynamic event such as a high-speed projectile impacting a target. The microscope assembly consists primarily of four Permanent Magnet Quadrupoles (PMQ's) that are supported on movable platforms. The platform supports, along with the rest of the support structure, are designed to withstand the residual dynamic loads that are expected from the dynamic tests. This paper covers the mechanical design of the microscope assembly, including the remote positioning system that allows for fine-tuning the focus of an object being imaged.
Contributing Partner: UNT Libraries Government Documents Department
Support of Gulf of Mexico Hydrate Research Consortium: Activities of Support Establishment of a Sea Floor Monitoring Station Project

Support of Gulf of Mexico Hydrate Research Consortium: Activities of Support Establishment of a Sea Floor Monitoring Station Project

Date: May 31, 2008
Creator: Woolsey, J. Robert; McGee, Thomas & Lutken, Carol
Description: The Gulf of Mexico Hydrates Research Consortium (GOM-HRC) was established in 1999 to assemble leaders in gas hydrates research that shared the need for a way to conduct investigations of gas hydrates and their stability zone in the Gulf of Mexico in situ on a more-or-less continuous basis. The primary objective of the group is to design and emplace a remote monitoring station or sea floor observatory (SFO) on the sea floor in the northern Gulf of Mexico, in an area where gas hydrates are known to be present at, or just below, the sea floor and to discover the configuration and composition of the subsurface pathways or 'plumbing' through which fluids migrate into and out of the hydrate stability zone (HSZ) to the sediment-water interface. Monitoring changes in this zone and linking them to coincident and perhaps consequent events at the seafloor and within the water column is the eventual goal of the Consortium. This mission includes investigations of the physical, chemical and biological components of the gas hydrate stability zone - the sea-floor/sediment-water interface, the near-sea-floor water column, and the shallow subsurface sediments. The eventual goal is to monitor changes in the hydrate stability zone over time. Establishment ...
Contributing Partner: UNT Libraries Government Documents Department
Observations on Faults and Associated Permeability Structures in Hydrogeologic Units at the Nevada Test Site

Observations on Faults and Associated Permeability Structures in Hydrogeologic Units at the Nevada Test Site

Date: March 30, 2009
Creator: Prothro, Lance B.; Drellack, Sigmund L.; Haugstad, Dawn N.; Huckins-Gang, Heather E. & Townsend, Margaret J.
Description: Observational data on Nevada Test Site (NTS) faults were gathered from a variety of sources, including surface and tunnel exposures, core samples, geophysical logs, and down-hole cameras. These data show that NTS fault characteristics and fault zone permeability structures are similar to those of faults studied in other regions. Faults at the NTS form complex and heterogeneous fault zones with flow properties that vary in both space and time. Flow property variability within fault zones can be broken down into four major components that allow for the development of a simplified, first approximation model of NTS fault zones. This conceptual model can be used as a general guide during development and evaluation of groundwater flow and contaminate transport models at the NTS.
Contributing Partner: UNT Libraries Government Documents Department
Notification of Concurrence - K-25/K-27 D&D Project, ETTP - Change Number of EMWMF Waste Lots in the Waste Handling Plan for Demolition of the K-25 and K-27 Building Structures and Remaining Components Located at the ETTP, Oak Ridge, TN From Two to Three

Notification of Concurrence - K-25/K-27 D&D Project, ETTP - Change Number of EMWMF Waste Lots in the Waste Handling Plan for Demolition of the K-25 and K-27 Building Structures and Remaining Components Located at the ETTP, Oak Ridge, TN From Two to Three

Date: February 11, 2009
Creator: K.D., Trice
Description: Section 5.1 of the approved Waste Handling Plan for Demolition ofthe K-25 and K-2 7 Building Structures and Remaining Components Located at the East Tennessee Technology Park, Oak Ridge, Tennessee (WHP) includes two Environmental Management Waste Management (EMWMF) waste lots: (1) Asbestos-contaminated roofing/transite; and (2) Construction debris, such as nonasbestos roofing, structural steel/miscellaneous metal/equipment, nonradiological piping, wood, and miscellaneous small quantities of concrete. This concurrence form adds an additional EMWMF waste lot 6.47 for lavatory sink drains. Based on an analysis of the building structure characterization data, the only individual building structure with either an analytic carcinogenic or Hazard Index (HI) sum-of-fractions (SOF) greater than 1 is the lavatory sink drains (Table 1). The HI SOF for the lavatory sink drains is 1.34 (Table 2). When all media are combined with the material of construction calculations, the HI SOF is 1.22 (Table 3). However, when the lavatory sink drains are segregated from all other media, the HI SOF is only 0.256, which is well below the EMWMF waste acceptance criteria SOF limit of 1 (Table 4). Given the large volume (124, 625 cubic yards) of other building structure media with a small HI SOF of 0.256 and the small volume ...
Contributing Partner: UNT Libraries Government Documents Department
Integrating externally developed systems for SNS Linac cooling and vacuum.

Integrating externally developed systems for SNS Linac cooling and vacuum.

Date: January 1, 2001
Creator: Marroquin, P. S. (Pilar S.)
Description: External contractors are developing the local cooling and vacuum control systems for the Spallation Neutron Source (SNS) linac. Soon these systems will be integrated into the facility-wide controls system. Allen-Bradley Logix5000 series programmable controllers, populated with appropriate input/output modules, were selected as the local controllers. These controllers will be interfaced to the facility-wide control system via VME systems with PowerPC processors running the Wind River VxWorks operating system and Experimental Physics and Industrial Control System (EPICS) front-end controller software. This paper describes the interface and integration issues driven by project, cooling system and vacuum system requirements and hardware selections.
Contributing Partner: UNT Libraries Government Documents Department
Final Technical Report

Final Technical Report

Date: September 8, 2009
Creator: Stenzel, Reiner & Urrutia, J. Manuel
Description: The nonlinear physics of electron magnetohydrodynamics (EMHD) in plasmas. Time-varying wave magnetic field exceeding the background magnetic field produces highly nonlinear whistler mode since the wave dispersion depends on the total magnetic field. There exists no theory for such whistler modes. The present experimental work is the first one to explore this regime of nonlinear whistlers. A field-reversed configuration has been found which has the same vortex topology as an MHD spheromak, termed a whistler spheromak. Whistler mirrors have compressed and twisted field lines propagating in the whistler mode. Their helicity properties have been studied. Whistler spheromaks and mirrors have different propagation and damping characteristics. Wave collisions have been studied. Head-on collisions of two whistler spheromaks form a stationary field-reversed configuration (FRC) without helicity. When whistler spheromaks are excited the toroidal current flows mainly in the toroidal null line. It is only carried by electrons since ion currents and displacement currents are negligible. A change in the poloidal (axial) magnetic field induces a toroidal electric field which drives the current. Magnetic energy is dissipated and converted into electron kinetic energy. This process is called magnetic reconnection in 2D geometries, which are simplifications for theoretical convenience but rarely occur in nature. ...
Contributing Partner: UNT Libraries Government Documents Department
A metamodel-based approach to model validation for nonlinear finite element simulations

A metamodel-based approach to model validation for nonlinear finite element simulations

Date: January 1, 2001
Creator: Doebling, S. W. (Scott W.); Hemez, F. M. (François M.); Schultze, J. F. (John F.) & Cundy, A. L. (Amanda L.)
Description: Metamodeling, also known as response surface analysis, is the de facto standard for mathematical representation of complex phenomena in many fields, especially when first principles physical relationships are not well-defined, e.g. economics, climatology, and government policy. Metamodels provide a computationally efficient, low-dimension relationship for studying the behavior of a physical system. They can be used for understanding the physical system, predicting its response, optimizing its design or the parameters in a physical model, and performing verification and validation. Metamodels can be derived from simulation results or fit directly to observed test data. In structural dynamics, typical practice is to develop a first-principles-based model such as a finite element model to study the behavior of the system. However, it is common that the features of interest in a structural dynamics simulation are relatively low order (e.g. first few modal frequencies, peak acceleration at certain locations) and sensitive to relatively few model and simulation parameters. In these cases, metamodeling provides a convenient format to facilitate activities of model validation, including parameter screening, sensitivity analysis [3], uncertainty analysis, and test/analysis correlation. This paper describes the creation of metamodels, and presents some examples of how metamodels can be employed to facilitate model validation for ...
Contributing Partner: UNT Libraries Government Documents Department
DANCE : a 4[pi] barium fluoride detector for measuring neutron capture on unstable nuclei /.

DANCE : a 4[pi] barium fluoride detector for measuring neutron capture on unstable nuclei /.

Date: January 1, 2002
Creator: Ullmann, J. L. (John L.); Haight, Robert C.; Hunt, L. F. (Lloyd F.); Reifarth, R. (Rene); Rundberg, R. S. (Robert S.); Bredeweg, T. A. (Todd A) et al.
Description: Measurements of neutron capture on unstable nuclei are important for studies of s-process nucleosynthesis, nuclear waste transmutation, and stewardship science. A 160-element, 4{pi} barium fluoride detector array, and associated neutron flight path, is being constructed to make capture measurements at the moderated neutron spallation source at LANSCE. Measurements can be made on as little as 1 mg of sample material over energies from near thermal to near 100 keV. The design of the DANCE array is described and neutron flux measurements from flight path commissioning are shown. The array is expected to be complete by the end of 2002.
Contributing Partner: UNT Libraries Government Documents Department
Multiscale simulations of alloy phase stability

Multiscale simulations of alloy phase stability

Date: January 1, 2002
Creator: Stan, M. (Marius); Baskes, M. I. (Michael I.); Valone, S. M. (Steven M.); Chen, S. P. (Shao-Ping) & Kothe, D. B. (Douglas B.)
Description: First principles, atomic scale and continuum level models are combined to predict thermodynamic properties of alloys and stability of phases. Many-body interactions, as well as vacancies, defects, and non-stoichiometry are included in the modeling process and the structural stability of hypothetical phases is evaluated. The resulted thermodynamic functions and phase diagrams are integrated in a casting simulation computer program. The process of relating microscopic modeling results to the macroscopic heat transfer and phase equilibrium calculations is detailed to emphasize the self-consistency of the approach and to identify the potential sources of errors. The sequence: data acquisition, modeling, prediction experimental validation, is illustrated for several recent results in actinide based alloys.
Contributing Partner: UNT Libraries Government Documents Department
DNC / CRONOS Deployment 703040

DNC / CRONOS Deployment 703040

Date: March 13, 2009
Creator: Kanies, Tim
Description: KCP tested a classified DNC / CRONOS as a pilot project in FY06 in the Reservoir Machining area. The pilot proved as a successful way to distribute classified NC Programs to machines that run both classified and unclassified programs securely. This also allows for elimination of CREM for machines which had to swap out classified and unclassified hard drives previously. This project’s purpose is to rollout this technology to the remaining machining areas, predominately Department B, Department C and Department A. Associated with this activity is the modification of business practices in the Tool Room / Model Shop areas and to address licensing issues for MASTERCAM to incorporate DNC CRONOS.
Contributing Partner: UNT Libraries Government Documents Department
Management of the Area 5 Radioactive Waste Management Site using decision-based, probabilistic performance assessment modeling

Management of the Area 5 Radioactive Waste Management Site using decision-based, probabilistic performance assessment modeling

Date: January 1, 2003
Creator: Carilli, J. (Jhon); Crowe, Bruce M.; Black, P. (Paul); Tauxe, J. (John); Stockton, T. (Tom); Catlett, K. (Kate) et al.
Description: None
Contributing Partner: UNT Libraries Government Documents Department
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