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Liquid Scoping Study for Tritium-Lean, Fast Ignition Inertial Fusion Energy Power Plants (open access)

Liquid Scoping Study for Tritium-Lean, Fast Ignition Inertial Fusion Energy Power Plants

In a thick-liquid protected chamber design, such as HYLIFE-II, a molten-salt is used to attenuate neutrons and protect the chamber structures from radiation damage. The molten-salt absorbs some of the material and energy given off by the target explosion. In the case of a fast ignition inertial fusion system, advanced targets have been proposed that may be Self-sufficient in the tritium breeding (i.e., the amount of tritium bred in target exceeds the amount burned). These ''tritium-lean'' targets contain approximately 0.5% tritium and 99.5% deuterium, but require a large pr of 10-20 g/cm{sup 2}. Although most of the yield is provided by D-T reactions, the majority of fusion reactions are D-D, which produces a net surplus of tritium. This aspect allows for greater freedom when selecting a liquid for the protective blanket (lithium-bearing compounds are not required). This study assesses characteristics of many single, binary, and ternary molten-salts. Using the NIST Properties of Molten Salts Database, approximately 4300 molten-salts were included in the study [1]. As an initial screening, salts were evaluated for their safety and environmental (S&E) characteristics, which included an assessment of waste disposal rating, contact dose, and radioactive afterheat. Salts that passed the S&E criteria were then evaluated …
Date: August 14, 2001
Creator: Schmitt, R. C.; Latkowski, J. F.; Durbin, S. G.; Meier, W. R. & Reyes, S.
System: The UNT Digital Library
Veterans Issues in the 107th Congress (open access)

Veterans Issues in the 107th Congress

None
Date: August 14, 2001
Creator: unknown
System: The UNT Digital Library
Studies of Dynamic Properties of Shock Compressed FCC Crystals by in Situ Dynamic X-Ray Diffraction (open access)

Studies of Dynamic Properties of Shock Compressed FCC Crystals by in Situ Dynamic X-Ray Diffraction

There were 5 laser experiments conducted to date in FY-01 under the ongoing project to study the response of single crystal fcc materials under shock compression. An additional 10 laser shots are planned for August, 2001. This work has focused on developing capability to record diffraction from multiple lattice planes during the passage of a shock through a thin foil of single crystal copper, while simultaneously performing separate shock sample recovery experiments to study the residual deformation structure in the recovered samples.
Date: August 14, 2001
Creator: Baldis, H.; Kalantar, D. H.; Remington, B. A.; Belak, J.; Colvin, J.; Boehly, T. R. et al.
System: The UNT Digital Library
Monitoring the Durability Performance of Concrete in Nuclear Waste Containment (open access)

Monitoring the Durability Performance of Concrete in Nuclear Waste Containment

OAK-B135 Monitoring the Durability Performance of Concrete in Nuclear Waste Containment
Date: August 14, 2001
Creator: Ulm, Franz-Josef
System: The UNT Digital Library
Impoundment and Sale of Cattle Trespassing on Federal Public Lands (open access)

Impoundment and Sale of Cattle Trespassing on Federal Public Lands

This report explores the authority of BLM personnel regarding unauthorized cattle by reviewing the statutory authorities of BLM over the federal rangelands under its administration, and the regulations and administrative materials implementing those authorities in the context of grazing, trespass, impoundment and sale of unauthorized livestock.
Date: August 14, 2001
Creator: Baldwin, Pamela
System: The UNT Digital Library
Physics of Compact Advanced Stellarators (open access)

Physics of Compact Advanced Stellarators

Compact optimized stellarators offer novel solutions for confining high-beta plasmas and developing magnetic confinement fusion. The 3-D plasma shape can be designed to enhance the MHD stability without feedback or nearby conducting structures and provide drift-orbit confinement similar to tokamaks. These configurations offer the possibility of combining the steady-state low-recirculating power, external control, and disruption resilience of previous stellarators with the low-aspect ratio, high beta-limit, and good confinement of advanced tokamaks. Quasi-axisymmetric equilibria have been developed for the proposed National Compact Stellarator Experiment (NCSX) with average aspect ratio 4-4.4 and average elongation of approximately 1.8. Even with bootstrap-current consistent profiles, they are passively stable to the ballooning, kink, vertical, Mercier, and neoclassical-tearing modes for beta > 4%, without the need for external feedback or conducting walls. The bootstrap current generates only 1/4 of the magnetic rotational transform at beta = 4% (the rest is from the coils), thus the equilibrium is much less nonlinear and is more controllable than similar advanced tokamaks. The enhanced stability is a result of ''reversed'' global shear, the spatial distribution of local shear, and the large fraction of externally generated transform. Transport simulations show adequate fast-ion confinement and thermal neoclassical transport similar to equivalent tokamaks. …
Date: August 14, 2001
Creator: Zarnstorff, M. C.; Berry, L. A.; Brooks, A.; Fredrickson, E.; Fu, G. Y.; Hirshman, S. et al.
System: The UNT Digital Library
Report of the Snowmass M6 Working Group on High Intensity Proton Sources (open access)

Report of the Snowmass M6 Working Group on High Intensity Proton Sources

The M6 working group had more than 40 active participants (listed in Section 4). During the three weeks at Snowmass, there were about 50 presentations, covering a wide range of topics associated with high intensity proton sources. The talks are listed in Section 5. This group also had joint sessions with a number of other working groups, including E1 (Neutrino Factories and Muon Colliders), E5 (Fixed-Target Experiments), M1 (Muon Based Systems), T4 (Particle Sources), T5 (Beam dynamics), T7 (High Performance Computing) and T9 (Diagnostics). The M6 group performed a survey of the beam parameters of existing and proposed high intensity proton sources, in particular, of the proton drivers. The results are listed in Table 1. These parameters are compared with the requirements of high-energy physics users of secondary beams in Working Groups E1 and E5. According to the consensus reached in the E1 and E5 groups, the U.S. HEP program requires an intense proton source, a 1-4 MW Proton Driver, by the end of this decade.
Date: August 14, 2001
Creator: Chou, W. & Wei, J.
System: The UNT Digital Library
Democratic Republic of the Congo: Peace Process and Background (open access)

Democratic Republic of the Congo: Peace Process and Background

The purpose of this report is to review the status of the Democratic Republic of the Congo peace process, provide background on recent conflicts in the Congo; briefly summarize the political history that led to these conflicts; and assess prospects for the future. U.S. Congo policy and congressional involvement are also described.
Date: August 14, 2001
Creator: Copson, Raymond W.
System: The UNT Digital Library