A 6.3 T Bend Magnet for the Advanced Light Source (open access)

A 6.3 T Bend Magnet for the Advanced Light Source

The Advanced Light Source (ALS) is a 1.5 to 1.9 GeV high-brightness electron storage ring operating at Lawrence Berkeley Laboratory (LBL) that provides synchrotron radiation for a large variety of users. It Is proposed to replace three of the thirty six 1.5T, one meter long bend magnets with very sbort high-field superconductlng (SC) dipoles. These magnets would provide bend-magnet synchrotron radiation to six bcamlines with a critical energy of at least 6 keV that is much better suited for protein crystallography and other small-sample x-ray diffraction and adsorption studies, than is currently available at the ALS. The magnet design is described, including coil, yoke, magnetic field analysis, and cyrostat. A prototype magnet is under construction at LBL.
Date: June 7, 1995
Creator: Taylor, C. E. & Caspi, S.
System: The UNT Digital Library
Evaluation of alternative chemical additives for high-level waste vitrification feed preparation processing (open access)

Evaluation of alternative chemical additives for high-level waste vitrification feed preparation processing

During the development of the feed processing flowsheet for the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS), research had shown that use of formic acid (HCOOH) could accomplish several processing objectives with one chemical addition. These objectives included the decomposition of tetraphenylborate, chemical reduction of mercury, production of acceptable rheological properties in the feed slurry, and controlling the oxidation state of the glass melt pool. However, the DEPF research had not shown that some vitrification slurry feeds had a tendency to evolve hydrogen (H{sub 2}) and ammonia (NH{sub 3}) as the result of catalytic decomposition of CHOOH with noble metals (rhodium, ruthenium, palladium) in the feed. Testing conducted at Pacific Northwest Laboratory and later at the Savannah River Technical Center showed that the H{sub 2} and NH{sub 3} could evolve at appreciable rates and quantities. The explosive nature of H{sub 2} and NH{sub 3} (as ammonium nitrate) warranted significant mitigation control and redesign of both facilities. At the time the explosive gas evolution was discovered, the DWPF was already under construction and an immediate hardware fix in tandem with flowsheet changes was necessary. However, the Hanford Waste Vitrification Plant (HWVP) was in the design phase and …
Date: June 7, 1995
Creator: Seymour, R.G.
System: The UNT Digital Library
Experimental investigation of fast electron diffusion during ECRH (open access)

Experimental investigation of fast electron diffusion during ECRH

The spatial diffusion of fast electrons created by electron cyclotron resonant heating (ECRH) is examined using electron cyclotron emissions viewed along a nearly vertical chord in the TEXT-U tokamak. Enhanced emission at frequencies downshifted from the cold cyclotron frequency is attributed to non-thermal electrons. The emission spectra during ECRH are consistent with the presence of low density suprathermal electrons. Comparison of the spectra measured during ECRH with a bounce averaged Fokker-Planck code which incorporates the effects of magnetic and/or electrostatic turbulence on the distribution function, shows that the level of magnetic fluctuations in the center of TEXT-U is between 3 and 5 {times} 10{sup {minus}5}. This level of magnetic fluctuation is a factor of 2 to 5 too small to explain the transport of thermal electrons (E {approximately} 1 keV) in TEXT. Thus, magnetic fluctuations are an unlikely major cause of the transport of thermal electrons in TEXT.
Date: June 7, 1995
Creator: Steimle, R.F.; Roberts, D.R. & Giruzzi, G.
System: The UNT Digital Library
Mechanical Properties of Thermally Aged Cast Stainless Steels From Shippingport Reactor Components. (open access)

Mechanical Properties of Thermally Aged Cast Stainless Steels From Shippingport Reactor Components.

Thermal embrittlement of static-cast CF-8 stainless steel components from the decommissioned Shippingport reactor has been characterized. Cast stainless steel materials were obtained from four cold-leg check valves, three hot-leg main shutoff valves, and two pump volutes. The actual time-at-temperature for the materials was {approx}13 y at {approx}281 C (538 F) for the hot-leg components and {approx}264 C (507 F) for the cold-leg components. Baseline mechanical properties for as-cast material were determined from tests on either recovery-annealed material, i.e., annealed for 1 h at 550 C and then water quenched, or material from the cooler region of the component. The Shippingport materials show modest decreases in fracture toughness and Charpy-impact properties and a small increase in tensile strength because of relatively low service temperatures and ferrite content of the steel. The procedure and correlations developed at Argonne National Laboratory for estimating mechanical properties of cast stainless steels predict accurate or slightly lower values for Charpy-impact energy, tensile flow stress, fracture toughness J-R curve, and JIC of the materials. The kinetics of thermal embrittlement and degree of embrittlement at saturation, i.e., the minimum impact energy achieved after long-term aging, were established from materials that were aged further in the laboratory. The results …
Date: June 7, 1995
Creator: Chopra, O. K.; Shack, W. J. & Technology, Energy
System: The UNT Digital Library
Statements of work for FY 1996 to 2001 for the Hanford Low-Level Tank Waste Performance Assessment Project (open access)

Statements of work for FY 1996 to 2001 for the Hanford Low-Level Tank Waste Performance Assessment Project

The statements of work for each activity and task of the Hanford Low-Level Tank Waste Performance Assessment project are given for the fiscal years 1996 through 2001. The end product of this program is approval of a final performance assessment by the Department of Energy in the year 2000.
Date: June 7, 1995
Creator: Mann, F. M.
System: The UNT Digital Library