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Recent Test Results of the High Field Nb3Sn Dipole Magnet HD2 (open access)

Recent Test Results of the High Field Nb3Sn Dipole Magnet HD2

The 1 m long Nb{sub 3}Sn dipole magnet HD2, fabricated and tested at Lawrence Berkeley National Laboratory, represents a step towards the development of block-type accelerator quality magnets operating in the range of 13-15 T. The magnet design features two coil modules composed of two layers wound around a titanium-alloy pole. The layer 1 pole includes a round cutout to provide room for a bore tube with a clear aperture of 36 mm. After a first series of tests where HD2 reached a maximum bore field of 13.8 T, corresponding to an estimated peak field on the conductor of 14.5 T, the magnet was disassembled and reloaded without the bore tube and with a clear aperture increased to 43 mm. We describe in this paper the magnet training observed in two consecutive tests after the removal of the bore tube, with a comparison of the quench performance with respect to the previous tests. An analysis of the voltage signals recorded before and after training quenches is then presented and discussed, and the results of coil visual inspections reported.
Date: October 19, 2009
Creator: Ferracin, P.; Bingham, B.; Caspi, S.; Cheng, D. W.; Dietderich, D. R.; Felice, H. et al.
Object Type: Article
System: The UNT Digital Library
Design of a High Field Nb3Al Common Coil Magnet (open access)

Design of a High Field Nb3Al Common Coil Magnet

A high field Nb{sub 3}Al common coil magnet is under development as an R&D of 'Advanced Superconducting Magnets for the LHC Luminosity Upgrade', in the framework of the CERN-KEK cooperation program. The goal of this research is to demonstrate the feasibility of high field magnet wound with Nb{sub 3}Al cable. The common coil approach and the shell-based structure were adopted in the design of this magnet. Besides three Nb{sub 3}Al coils, two Nb{sub 3}Sn coils were included to increase the peak field of the whole magnet. The two types of coils were designed with different straight lengths to reduce the peak field of the Nb{sub 3}Sn coils. The peak fields of the Nb{sub 3}Al and Nb{sub 3}Sn coils are 13.1 T and 11.8 T respectively. An aluminum shell together with four aluminum rods applies stress to the coils to overcome the Lorenz force during excitation. Two different support structures for the superconducting coils were introduced in this paper. The development status is also presented.
Date: October 19, 2009
Creator: Xu, Qingjin; Sasaki, Kenichi; Nakamoto, Tatsushi; Terashima, Akio; Tsuchiya, Kiyosumi; Yamamoto, Akira et al.
Object Type: Article
System: The UNT Digital Library
Self-Reliability and Motivation in a Nuclear Security Culture Enhancement Program (open access)

Self-Reliability and Motivation in a Nuclear Security Culture Enhancement Program

The threat of nuclear terrorism has become a global concern. Many countries continue to make efforts to strengthen nuclear security by enhancing systems of nuclear material protection, control, and accounting (MPC&A). Though MPC&A systems can significantly upgrade nuclear security, they do not eliminate the "human factor." Gen. Eugene Habiger, a former "Assistant Secretary for Safeguards and Security" at the U.S. Department of Energy’s (DOE) nuclear-weapons complex and a former commander of U.S. strategic nuclear forces, has observed that "good security is 20% equipment and 80% people." Although eliminating the "human factor" is not possible, accounting for and mitigating the risk of the insider threat is an essential element in establishing an effective nuclear security culture. This paper will consider the organizational role in mitigating the risk associated with the malicious insider through monitoring and enhancing human reliability and motivation as well as enhancing the nuclear security culture.
Date: October 19, 2009
Creator: Rogers, E.; deBoer, G.; Crawford, C.; De Castro, K. & Landers, J.
Object Type: Article
System: The UNT Digital Library
Transitions of Dislocation Glide to Twinning and Shear Transformation in Shock-Deformed Tantalum (open access)

Transitions of Dislocation Glide to Twinning and Shear Transformation in Shock-Deformed Tantalum

Recent TEM studies of deformation substructures developed in tantalum and tantalum-tungsten alloys shock-deformed at a peak pressure {approx}45 GPa have revealed the occurrence of shock-induced phase transformation [i.e., {alpha} (bcc) {yields} {omega} (hexagonal) transition] in addition to shock-induced deformation twinning. The volume fraction of twin and {omega} domains increases with increasing content of tungsten. A controversy arises since tantalum exhibits no clear equilibrium solid-state phase transformation under hydrostatic pressures up to 174 GPa. It is known that phase stability of a material system under different temperatures and pressures is determined by system free energy. That is, a structural phase that has the lowest free energy will be stable. For pressure-induced phase transformation under hydrostatic-pressure conditions, tantalum may undergo phase transition when the free energy of a competing phase {omega} becomes smaller than that of the parent phase {alpha} above a critical pressure (P{sub eq}), i.e., the equilibrium {alpha} {yields} {omega} transition occurs when the pressure increases above P{sub eq}. However, it is also known that material shocked under dynamic pressure can lead to a considerable increase in temperature, and the higher the applied pressure the higher the overheat temperature. This means a higher pressure is required to achieve an equivalent …
Date: October 19, 2009
Creator: Hsiung, L L; Campbell, G H & McNaney, J M
Object Type: Article
System: The UNT Digital Library
MECHANISTIC UNDERSTANDING OF CAUSTIC CRACKING OF CARBON STEELS (open access)

MECHANISTIC UNDERSTANDING OF CAUSTIC CRACKING OF CARBON STEELS

Liquid waste generated by the PUREX process for separation of nuclear materials is concentrated and stored in Type IV single-shell carbon steel tanks at the Savannah River Site (SRS). The Type IV tanks for this waste do not have cooling coils and have not undergone heat treatment to stress-relieve the tanks. After the waste is concentrated by evaporation, it becomes very alkaline and can cause stress corrosion cracking (SCC) and pitting corrosion of the tank materials. SRS has experienced leakage from non-stress-relieved waste tanks constructed of A285 carbon steel and pitting of A212 carbon steel tanks in the vapor space. An investigation of tank materials has been undertaken at SRS to develop a basic understanding of caustic SCC of A285 and A212 grade carbon steels exposed to aqueous solutions, primarily containing sodium hydroxide (NaOH), sodium nitrate (NaNO{sub 3}), and sodium nitrite (NaNO{sub 2}) at temperatures relevant to the operating conditions of both the F and H area plants. This report presents the results of this corrosion testing program. Electrochemical tests were designed using unstressed coupons in a simulated tank environment. The purpose of this testing was to determine the corrosion susceptibility of the tank materials as a function of chemical …
Date: October 19, 2009
Creator: Garcia-Diaz, B. & Roy, A.
Object Type: Article
System: The UNT Digital Library
Imaging the molecular dynamics of dissociative electron attachment to water (open access)

Imaging the molecular dynamics of dissociative electron attachment to water

Momentum imaging experiments on dissociative electron attachment to the water molecule are combined with ab initio theoretical calculations of the angular dependence of the quantum mechanical amplitude for electron attachment to provide a detailed picture of the molecular dynamics of dissociation attachment via the two lowest energy Feshbach resonances. The combination of momentum imaging experiments and theory can reveal dissociation dynamics for which the axial recoil approximation breaks down and thus provides a powerful reaction microscope for DEA to polyatomics.
Date: October 19, 2009
Creator: Adaniya, Hidihito; Rudek, B.; Osipov, Timur; Haxton, Dan; Weber, Thorsten; Rescigno, Thomas N. et al.
Object Type: Article
System: The UNT Digital Library
Internal electric-field-lines distribution in CdZnTe detectors measured using X-ray mapping (open access)

Internal electric-field-lines distribution in CdZnTe detectors measured using X-ray mapping

The ideal operation of CdZnTe devices entails having a uniformly distributed internal electric field. Such uniformity especially is critical for thick long-drift-length detectors, such as large-volume CPG and 3-D multi-pixel devices. Using a high-spatial resolution X-ray mapping technique, we investigated the distribution of the electric field in real devices. Our measurements demonstrate that in thin detectors, <5 mm, the electric field-lines tend to bend away from the side surfaces (i.e., a focusing effect). In thick detectors, >1 cm, with a large aspect ratio (thickness-to-width ratio), we observed two effects: the electric field lines bending away from or towards the side surfaces, which we called, respectively, the focusing field-line distribution and the defocusing field-line distribution. In addition to these large-scale variations, the field-line distributions were locally perturbed by the presence of extended defects and residual strains existing inside the crystals. We present our data clearly demonstrating the non-uniformity of the internal electric field.
Date: October 19, 2009
Creator: Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Hossain, A.; Yang, G.; Yao, H. W. et al.
Object Type: Article
System: The UNT Digital Library
Proton Bunching Options (open access)

Proton Bunching Options

Muon Colliders need intense, very short, proton bunches. The requirements are presented and a number of possible bunching systems discussed. The best solution uses a small super-conducting buncher ring with 6 bunches that are taken though separate transports and combined on the target.
Date: October 19, 2009
Creator: Palmer, Robert B.
Object Type: Article
System: The UNT Digital Library
STABILITY OF DOW CORNING Q2-3183A ANTIFOAM IN IRRADIATED HYDROXIDE SOLUTION (open access)

STABILITY OF DOW CORNING Q2-3183A ANTIFOAM IN IRRADIATED HYDROXIDE SOLUTION

Researchers at the Savannah River National Laboratory (SRNL) examined the stability of Dow Corning Q2-3183A antifoam to radiation and aqueous hydroxide solutions. Initial foam control studies with Hanford tank waste showed the antifoam reduced foaming. The antifoam was further tested using simulated Hanford tank waste spiked with antifoam that was heated and irradiated (2.1 x 10{sup 4} rad/h) at conditions (90 C, 3 M NaOH, 8 h) expected in the processing of radioactive waste through the Waste Treatment and Immobilization Plant (WTP) at Hanford. After irradiation, the concentration of the major polymer components polydimethylsiloxane (PDMS) and polypropylene glycol (PPG) in the antifoam was determined by gel permeation chromatography (GPC). No loss of the major polymer components was observed after 24 h and only 15 wt% loss of PDMS was reported after 48 h. The presence of degradation products were not observed by gas chromatography (GC), gas chromatography mass spectrometry (GCMS) or high performance liquid chromatography mass spectrometry (HPLC-MS). G values were calculated from the GPC analysis and tabulated. The findings indicate the antifoam is stable for 24 h after exposure to gamma radiation, heat, and alkaline simulated waste.
Date: October 19, 2009
Creator: White, T; Crawford, C; Burket, P & Calloway, B
Object Type: Article
System: The UNT Digital Library

2009 NGSI Safeguards Courses at DOE National Laboratories

PowerPoint Presentation
Date: October 19, 2009
Creator: Rosenthal, M. D.; Fishbone, L.; Kirk, B.; Boyer, B.; Doyle, J.; Meek, E. et al.
Object Type: Presentation
System: The UNT Digital Library
Self-Reliability and Motivation in a Nuclear Security Culture Enhancement Program (open access)

Self-Reliability and Motivation in a Nuclear Security Culture Enhancement Program

The threat of nuclear terrorism has become a global concern. Many countries continue to make efforts to strengthen nuclear security by enhancing systems of nuclear material protection, control, and accounting (MPC&A). Though MPC&A systems can significantly upgrade nuclear security, they do not eliminate the "human factor." This paper will describe some of the key elements of a comprehensive, sustainable nuclear security culture enhancement program and how implementation can mitigate the insider threat.
Date: October 19, 2009
Creator: Crawford, C.; de Boer, G.; De Castro, K.; Landers, J. & Rogers, E.
Object Type: Article
System: The UNT Digital Library
RESULTS FOR THE SECOND QUARTER 2009 TANK 50 WAC SLURRY SAMPLE CHEMICAL CONTAMINANT RESULTS (open access)

RESULTS FOR THE SECOND QUARTER 2009 TANK 50 WAC SLURRY SAMPLE CHEMICAL CONTAMINANT RESULTS

None
Date: October 19, 2009
Creator: Reigel, M.; Diprete, C. & Bibler, N.
Object Type: Report
System: The UNT Digital Library
Ferrimagnetic ordering of single crystal Fe1-xGax thin films (open access)

Ferrimagnetic ordering of single crystal Fe1-xGax thin films

Molecular beam epitaxy was used to deposit body centered cubic single crystal Fe{sub 1-x}Ga{sub x} thin films on MgO(001) and ZnSe/GaAs(001) substrates well beyond the bulk stability concentration of about 28%. The crystal quality of the substrate surface and each deposited layer was monitored in situ by reflection high energy electron diffraction. The magnetization of the samples as a function of Ga is found to decrease more rapidly than a simple dilution effect, and element-specific x-ray magnetic circular dichroism ascribes this trend to a decrease in the Fe moment and an induced moment in the Ga that is antialigned to the Fe moment.
Date: October 19, 2009
Creator: McClure, A.; Arenholz, E. & Idzerda, Y. U.
Object Type: Article
System: The UNT Digital Library
The Role of Quench-back in the Passive Quench Protection of Long Solenoids with Coil Sub-division (open access)

The Role of Quench-back in the Passive Quench Protection of Long Solenoids with Coil Sub-division

This paper describes how a passive quench protection system can be applied to long superconducting solenoid magnets. When a solenoid coil is long compared to its thickness, the magnet quench process will be dominated by the time needed for uench propagation along the magnet length. Quench-back will permit a long magnet to quench more rapidly in a passive way. Quenchback from a conductive (low resistivity) mandrel is essential for spreading the quench along the length of a magnet. The andrel must be inductively coupled to the magnet circuit that is being quenched. Current induced in the mandrel by di/dt in the magnet produces heat in the mandrel, which in turn causes the superconducting coil wound on the mandrel to quench. Sub-divisions often employed to reduce the voltages to ground within the coil. This paper explores when it is possible for quench-back to be employed for passive quench protection. The role of sub-division of the coil is discussed for long magnets.
Date: October 19, 2009
Creator: Green, Michael A.; Guo, XingLong; Wang, Li; Pan, Heng & Wu, Hong
Object Type: Article
System: The UNT Digital Library
Software-Defined Ultra-wideband Radio Communications: A New RF Technology for Emergency Response Applications (open access)

Software-Defined Ultra-wideband Radio Communications: A New RF Technology for Emergency Response Applications

Reliable wireless communication links for local-area (short-range) and regional (long-range) reach capabilities are crucial for emergency response to disasters. Lack of a dependable communication system can result in disruptions in the situational awareness between the local responders in the field and the emergency command and control centers. To date, all wireless communications systems such as cell phones and walkie-talkies use narrowband radio frequency (RF) signaling for data communication. However, the hostile radio propagation environment caused by collapsed structures and rubble in various disaster sites results in significant degradation and attenuation of narrowband RF signals, which ends up in frequent communication breakdowns. To address the challenges of reliable radio communication in disaster fields, we propose an approach to use ultra-wideband (UWB) or wideband RF waveforms for implementation on Software Defined Radio (SDR) platforms. Ultra-wideband communications has been proven by many research groups to be effective in addressing many of the limitations faced by conventional narrowband radio technologies. In addition, LLNL's radio and wireless team have shown significant success in field deployment of various UWB communications system for harsh environments based on LLNL's patented UWB modulation and equalization techniques. Furthermore, using software defined radio platform for UWB communications offers a great deal …
Date: October 19, 2009
Creator: Nekoogar, F. & Dowla, F.
Object Type: Article
System: The UNT Digital Library
The Results of Tests of the MICE Spectrometer Solenoids (open access)

The Results of Tests of the MICE Spectrometer Solenoids

The Muon Ionization Cooling Experiment (MICE) spectrometer solenoid magnets will be the first magnets to be installed within the MICE cooling channel. The spectrometer magnets are the largest magnets in both mass and surface area within the MICE ooling channel. Like all of the other magnets in MICE, the spectrometer solenoids are kept cold using 1.5 W (at 4.2 K) pulse tube coolers. The MICE spectrometer solenoid is quite possibly the largest magnet that has been cooled using small coolers. Two pectrometer magnets have been built and tested. This report discusses the results of current and cooler tests of both magnets.
Date: October 19, 2009
Creator: Green, Michael A. & Virostek, Steve P.
Object Type: Article
System: The UNT Digital Library
Measurements on Subscale Y-Ba-Cu-O Racetrack Coils at 77 K and Self-Field (open access)

Measurements on Subscale Y-Ba-Cu-O Racetrack Coils at 77 K and Self-Field

YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) tapes carry significant amount of current at fields beyond the limit of Nb-based conductors. This makes the YBCO tapes a possible conductor candidate for insert magnets to increase the bore field of Nb{sub 3}Sn high-field dipoles. As an initial step of the YBCO insert technology development, two subscale racetrack coils were wound using Kapton-insulated commercial YBCO tapes. Both coils had two layers; one had 3 turns in each layer and the other 10 turns. The coils were supported by G10 side rails and waxed strips and not impregnated. The critical current of the coils was measured at 77 K and self-field. A 2D model considering the magnetic-field dependence of the critical current was used to estimate the expected critical current. The measured results show that both coils reached 80%-95% of the expected values, indicating the feasibility of the design concept and fabrication process.
Date: October 19, 2009
Creator: Wang, X.; Caspi, S.; Cheng, D. W.; Dietderich, D. R.; Felice, H.; Ferracin, P. et al.
Object Type: Article
System: The UNT Digital Library
Progress on the Design and Fabrication of the MICE Focusing Magnets (open access)

Progress on the Design and Fabrication of the MICE Focusing Magnets

The Muon Ionization Cooling Experiment (MICE) focusing solenoid magnets focus the muon beam within the MICE cooling channel on a liquid or solid absorber that is within the warm bore of solenoid. The focusing magnet has a warm bore of 470 mm. his magnet consists of two coils 210-mm long that is separated by an aluminum mandrel that is 200 mm long. Each of the coils has its own leads. The coils may be operated in either the non-flip mode (solenoid mode with both coils at the same polarity) or the lip mode (quadrupole focusing mode where both coils are at opposite polarity). This report describes the focusing solenoid magnet design that will be built by the vendor. The progress on the construction of the first of the focusing magnets will also be discussed in this report. Ultimately three of these magnets will be built. These magnets will be cooled using a pair 1.5 W (at 4.2 K) pulse tube coolers.
Date: October 19, 2009
Creator: Green, Michael A.; Baynham, D. Elwyn; Bradshaw, Thomas W.; Cobb, John H.; Lau, Wing W. & Yang, Stephanie Q.
Object Type: Article
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 95, No. 42, Ed. 1 Monday, October 19, 2009 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 95, No. 42, Ed. 1 Monday, October 19, 2009

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: October 19, 2009
Creator: Hughes, Jamie
Object Type: Newspaper
System: The Gateway to Oklahoma History
Unlawful Internet Gambling Enforcement Act and Its Implementing Regulations (open access)

Unlawful Internet Gambling Enforcement Act and Its Implementing Regulations

This report contains an overview of the unlawful internet gambling enforcement act and its implementing regulations.
Date: October 19, 2009
Creator: Doyle, Charles & Yeh, Brian T.
Object Type: Report
System: The UNT Digital Library
Assembly and Loading of LQS01, a Shell-Based 3.7 m Long Nb3Sn Quadrupole Magnet for LARP (open access)

Assembly and Loading of LQS01, a Shell-Based 3.7 m Long Nb3Sn Quadrupole Magnet for LARP

The LHC Accelerator Research Program (LARP) has been engaged in the fabrication of the 3.7 m long quadrupole magnet LQS01 in order to demonstrate that Nb{sub 3}Sn magnets are a viable option for future LHC Luminosity upgrades. The LQS01 design, a scale-up of the 1 m long Technology Quadrupole TQS, includes four 3.4 m long cos(theta) coils contained in a support structure based on four 1 m long aluminum shells pre-tensioned with water-pressurized bladders (shell-type structure). In order to verify assembly procedures and loading operations, the structure was pre-stressed around solid aluminum 'dummy coils' and cooled-down to 77 K. Mechanical behavior and stress variations were monitored with strain gauges mounted on the structure and on the dummy coils. The dummy coils were then replaced with Nb{sub 3}Sn coils in a second assembly and loading procedure, in preparation for the cool-down and test. This paper reports on the cool-down test with dummy coils and on the assembly and loading of LQS01, with a comparison between 3D finite element model predictions and strain gauge data.
Date: October 19, 2009
Creator: Ferracin, P.; Ambrosio, G.; Anerella, M.; Bingham, B.; Bossert, R.; Caspi, S. et al.
Object Type: Article
System: The UNT Digital Library
Activation of Carbon-Hydrogen and Hydrogen-Hydrogen Bonds by Copper-Nitrenes: A Comparison of Density Functionality Theory with Single- and Multireference Correlation Consistent Composite Approaches (open access)

Activation of Carbon-Hydrogen and Hydrogen-Hydrogen Bonds by Copper-Nitrenes: A Comparison of Density Functionality Theory with Single- and Multireference Correlation Consistent Composite Approaches

Article on a comparison of density functional theory with single- and multireference correlation consistent composite approaches (ccCA).
Date: October 19, 2009
Creator: Tekarli, Sammer M.; Williams, T. Gavin & Cundari, Thomas R., 1964-
Object Type: Article
System: The UNT Digital Library
Oral History Interview with Joseph Williams, October 19, 2009 transcript

Oral History Interview with Joseph Williams, October 19, 2009

The National Museum of the Pacific War presents an oral interview with Joseph F. Williams. Williams was born 7 December 1921 in New Orleans. After being drafted into the US Army on 23 February 1943 he took basic training at Fort McClellan, Alabama for three months. Williams was then sent to Fort Dix, New Jersey where he was assigned to a headquarters company in the Quartermaster Corps. There he received driver training for various vehicles. On 18 January 1944 he sailed to Belfast, Ireland. In July 1944 he landed at Cherbourg, France with the 4029th Quartermaster Truck Company, a segregated unit. There his unit joined the 3rd Army and transported infantry to participate in the battle for Saint Lo, France. He saw General Patton on a weekly basis and recalls witnessing an incident where he demoted a colonel to sergeant because he had stopped a column of trucks hauling gasoline to his tankers. He was subjected to strafing and shelling by German aircraft and artillery on a regular basis. Williams remembers as Allied Forces advanced, German soldiers, some as young as twelve years of age, surrendered. He transported loads of prisoners back to secured areas. He describes being in a …
Date: October 19, 2009
Creator: Williams, Joseph F.
Object Type: Sound
System: The Portal to Texas History

Ensemble: 2009-10-19 – Spectrum

Access: Use of this item is restricted to the UNT Community
New music concert presented at the UNT College of Music Recital Hall.
Date: October 19, 2009
Creator: unknown
Object Type: Sound
System: The UNT Digital Library