Collapsing Bubble in Metal for High Energy Density Physics Study (open access)

Collapsing Bubble in Metal for High Energy Density Physics Study

This paper presents a new idea to produce matter in the high energy density physics (HEDP) regime in the laboratory using an intense ion beam. A gas bubble created inside a solid metal may collapse by driving it with an intense ion beam. The melted metal will compress the gas bubble and supply extra energy to it. Simulations show that the spherical implosion ratio can be about 5 and at the stagnation point, the maximum density, temperature and pressure inside the gas bubble can go up to nearly 2 times solid density, 10 eV and a few megabar (Mbar) respectively. The proposed experiment is the first to permit access into the Mbar regime with existing or near-term ion facilities, and opens up possibilities for new physics gained through careful comparisons of simulations with measurements of quantities like stagnation radius, peak temperature and peak pressure at the metal wall.
Date: April 13, 2011
Creator: Ng, S. F.; Barnard, J. J.; Leung, P. T. & Yu, S. S.
System: The UNT Digital Library
Evolution of Static Physical Properties in Plutonium by Self-irradiation Damage (open access)

Evolution of Static Physical Properties in Plutonium by Self-irradiation Damage

The alpha-decay of plutonium leads to the age-related change in physical properties. This paper presents updated results of age-related effects on enriched and reference alloys measured from immersion density, dilatometry, and mechanical tests. After nearly 100 equivalent years of aging, both the immersion density and dilatometry show that the enriched alloys are decreasing in density by less than 0.02% per year and now exhibit a near linear density decrease, without void swelling. The tensile tests show that the aging process increases the strength of plutonium alloys, followed by possible saturation past 70 equivalent years of age. The ultimate goal of this work is to develop capabilities to predict physical properties changed by aging effects.
Date: April 13, 2010
Creator: Chung, B W; Lema, K E & Hiromoto, D S
System: The UNT Digital Library
An Experimental and Theoretical Multi-Mbar Study of Ti-6Al-4V (open access)

An Experimental and Theoretical Multi-Mbar Study of Ti-6Al-4V

We report results from an experimental and theoretical study of the room temperature (RT) compression of the ternary alloy Ti-6Al-4V. In this work, we have extended knowledge of the equation of state (EOS) from 40 GPa to 221 GPa, and observed a different sequence of phase transitions to that reported previously for pure Ti.
Date: April 13, 2011
Creator: Tegner, B. E.; Macleod, S. G.; Cynn, H.; Proctor, J.; Evans, W. J.; McMahon, M. I. et al.
System: The UNT Digital Library
DEVELOPMENT OF ASME SECTION X CODE RULES FOR HIGH PRESSURE COMPOSITE HYDROGEN PRESSURE VESSELS WITH NON-LOAD SHARING LINERS (open access)

DEVELOPMENT OF ASME SECTION X CODE RULES FOR HIGH PRESSURE COMPOSITE HYDROGEN PRESSURE VESSELS WITH NON-LOAD SHARING LINERS

The Boiler and Pressure Vessel Project Team on Hydrogen Tanks was formed in 2004 to develop Code rules to address the various needs that had been identified for the design and construction of up to 15000 psi hydrogen storage vessel. One of these needs was the development of Code rules for high pressure composite vessels with non-load sharing liners for stationary applications. In 2009, ASME approved new Appendix 8, for Section X Code which contains the rules for these vessels. These vessels are designated as Class III vessels with design pressure ranging from 20.7 MPa (3,000 ps)i to 103.4 MPa (15,000 psi) and maximum allowable outside liner diameter of 2.54 m (100 inches). The maximum design life of these vessels is limited to 20 years. Design, fabrication, and examination requirements have been specified, included Acoustic Emission testing at time of manufacture. The Code rules include the design qualification testing of prototype vessels. Qualification includes proof, expansion, burst, cyclic fatigue, creep, flaw, permeability, torque, penetration, and environmental testing.
Date: April 13, 2010
Creator: Rawls, G.; Newhouse, N.; Rana, M.; Shelley, B. & Gorman, M.
System: The UNT Digital Library
A high-efficiency spin-resolved photoemission spectrometer combining time-of-flight spectroscopy with exchange-scattering polarimetry (open access)

A high-efficiency spin-resolved photoemission spectrometer combining time-of-flight spectroscopy with exchange-scattering polarimetry

We describe a spin-resolved electron spectrometer capable of uniquely efficient and high energy resolution measurements. Spin analysis is obtained through polarimetry based on low-energy exchange scattering from a ferromagnetic thin-film target. This approach can achieve a similar analyzing power (Sherman function) as state-of-the-art Mott scattering polarimeters, but with as much as 100 times improved efficiency due to increased reflectivity. Performance is further enhanced by integrating the polarimeter into a time-of-flight (TOF) based energy analysis scheme with a precise and flexible electrostatic lens system. The parallel acquisition of a range of electron kinetic energies afforded by the TOF approach results in an order of magnitude (or more) increase in efficiency compared to hemispherical analyzers. The lens system additionally features a 90 degrees bandpass filter, which by removing unwanted parts of the photoelectron distribution allows the TOF technique to be performed at low electron drift energy and high energy resolution within a wide range of experimental parameters. The spectrometer is ideally suited for high-resolution spin- and angle-resolved photoemission spectroscopy (spin-ARPES), and initial results are shown. The TOF approach makes the spectrometer especially ideal for time-resolved spin-ARPES experiments.
Date: April 13, 2010
Creator: Jozwiak, Chris M.; Graff, Jeff; Lebedev, Gennadi; Andresen, Nord; Schmid, Andreas; Fedorov, Alexei et al.
System: The UNT Digital Library
Multi-channel optical pyrometer for sub-nanosecond temperature measurements at NDCX-I/II (open access)

Multi-channel optical pyrometer for sub-nanosecond temperature measurements at NDCX-I/II

We present a detailed technical description of a fast multi-channel pyrometer designed for warm-dense-matter (WDM) experiments with intense heavy ion beams at the neutralized-drift-compression-experiment linear accelerator (NDCX-I/II) at Lawrence Berkeley National Laboratory (LBNL). The unique features of the described instrument are its sub-nanosecond temporal resolution (100 ps rise-time) and a broad range, 1,500 K - 12,000 K of measurable brightness temperatures in the visible and near-infrared regions of the spectrum. The working scheme, calibration procedure, experimental data obtained with the pyrometer and future applications are presented.
Date: April 13, 2011
Creator: Ni, P.A.; Bieniosek, F.M. & Waldron, W.L.
System: The UNT Digital Library
Cardiovascular function, compliance, and connective tissue remodeling in the turtle, Trachemys scripta, following thermal acclimation (open access)

Cardiovascular function, compliance, and connective tissue remodeling in the turtle, Trachemys scripta, following thermal acclimation

This article suggests that cold acclimation alters cardiac shunting patterns with an increased R-L shunt flow, achieved through reducing systemic resistance and increasing systemic blood flow.
Date: April 13, 2016
Creator: Keen, Adam N.; Shiels, Holly A. & Crossley, Dane A., II
System: The UNT Digital Library
The Microbial Detection Array Combined with Random Phi29-Amplification used as a Diagnostic Tool for Unbiased Virus Detection in Clinical Samples (open access)

The Microbial Detection Array Combined with Random Phi29-Amplification used as a Diagnostic Tool for Unbiased Virus Detection in Clinical Samples

None
Date: April 13, 2011
Creator: Erlandsson, L.; Rosenstierne, M. W.; McLoughlin, K.; Jaing, C. & Fomsgaard, A.
System: The UNT Digital Library
Large-scale Relativistic Configuration-interaction Calculations for the 2s-2p and 3s-3p Transition Energies of Xenon Ions (open access)

Large-scale Relativistic Configuration-interaction Calculations for the 2s-2p and 3s-3p Transition Energies of Xenon Ions

None
Date: April 13, 2010
Creator: Chen, M H & Cheng, K T
System: The UNT Digital Library
Directional Fast Neutron Detection using a Time Projection Chamber (open access)

Directional Fast Neutron Detection using a Time Projection Chamber

None
Date: April 13, 2010
Creator: Bowden, N.; Heffner, M.; Carosi, G.; Cater, D.; O'Malley, P.; Mintz, J. et al.
System: The UNT Digital Library