Many common scrap substitutes such as direct reduced iron pellets (DRI), hot briquetted iron (HBI), iron carbide, etc., contain significantly higher levels of phosphorus steelmaking for the production of higher quality steels, control of phosphorus levels in the metal will become a concern. This study has developed a more complete understanding of the behavior of phosphorus in DRI during EAF steelmaking, through a thorough investigation of the kinetics and thermodynamics of phosphorus transfer in the EAF based upon laboratory and plant experiments and trials. Laboratory experiments have shown that phosphorus mass transfer between oxide and metallic phases within commercial direct reduced iron pellets occurs rapidly upon melting according to the local equilibrium for these phases. Laboratory kinetic experiments indicate that under certain conditions, phosphorus mass transfer between slag and metal is influenced by dynamic phenomena, which affect the mass transfer coefficient for the reaction and/or the slag metal interfacial area. Plant trials were conducted to directly evaluate the conditions of mass transfer in the electric furnace and to determine the effects of different scrap substitute materials upon the slag chemistry, the behavior of phosphorus in the steel, and upon furnace yield. The data from these trials were also used to …

Algorithms for the treatment of special positions in 3-dimensional crystallographic space groups are presented. These include an algorithm for the determination of the site-symmetry group given the coordinates of a point, an algorithm for the determination of the exact location of the nearest special position, an algorithm for the assignment of a Wyckoff letter given the site-symmetry group, and an alternative algorithm for the assignment of a Wyckoff letter given the coordinates of a point directly. All algorithms are implemented in ISO C++ and are integrated into the Computational Crystallography Toolbox. The source code is freely available.

Deformation at grain boundaries is observed and a framework for boundary specific constitutive laws based upon geometric considerations of slip transfer is developed. Orientation images of a pseudo-internal surface during interrupted channel die deformations of a Cu bi-crystal show the heterogeneity of lattice rotation near the grain boundary. The experiments demonstrate that a region near the boundary is strongly influenced by neighboring grain deformation and lend support to the development of deformation models that include the effects of non-local slip system interaction.

Automatic grouping of voluminous data into meaningful structures is a challenging task frequently encountered in broad areas of science, engineering and information processing. These data clustering tasks are frequently performed in Euclidean space or a subspace chosen from principal component analysis (PCA). Here we describe a space obtained by a nonlinear scaling of PCA in which data objects self-aggregate automatically into clusters. Projection into this space gives sharp distinctions among clusters. Gene expression profiles of cancer tissue subtypes, Web hyperlink structure and Internet newsgroups are analyzed to illustrate interesting properties of the space.

Technologies are being developed by the US Department of Energy's (DOE) Nuclear Facility sites to convert low-level and mixed (hazardous and radioactive) wastes to a solid stabilized waste form for permanent disposal. One of the alternative technologies is vitrification into a borosilicate glass waste form. The Environmental Protection Agency (EPA) has declared vitrification the Best Demonstrated Available Technology (BDAT) for high-level radioactive mixed waste and produced a Handbook of Vitrification Technologies for Treatment of Hazardous and Radioactive Waste. The DOE Office of Technology Development (OTD) has taken the position that mixed waste needs to be stabilized to the highest level reasonably possible to ensure that the resulting waste forms will meet both current and future regulatory specifications. Stabilization of low level and hazardous wastes in glass are in accord with the 1988 Savannah River Technology Center (SRTC), then the Savannah River Laboratory (SRL), Professional Planning Committee (PPC) recommendation that high nitrate containing (low-level) wastes be incorporated into a low temperature glass (via a sol-gel technology). The investigation into this new technology was considered timely because of the potential for large waste volume reduction compared to solidification into cement.