A series of experiments was conducted using SRL 165 synthetic waste glass to investigate the effects of surface preparation and leaching solution composition on the alteration of the glass. Samples of glass with as-cast surfaces produced smooth reaction layers and some evidence for precipitation of secondary phases from solution. Secondary phases were more abundant in samples reacted in deionized water than for those reacted in a silicate solution. Samples with saw-cut surfaces showed a large reduction in surface roughness after 7 days of reaction in either solution. Reaction in silicate solution for up to 91 days produced no further change in surface morphology, while reaction in DIW produced a spongy surface that formed the substrate for further surface layer development. The differences in the surface morphology of the samples may create microclimates that control the details of development of alteration layers on the glass; however, the concentrations of elements in leaching solutions show differences of 50% or less between samples prepared with different surface conditions for tests of a few months duration. 6 refs., 7 figs., 1 tab.

An economic model is a tool for determining the justifiable cost of new sensors and subsystems with respect to value and operation. This process balances the R and D costs against the expense of maintaining current operations and allows for a method to calculate economic indices of performance that can be used as control points in deciding whether to continue development or suspend actions. The model can also be used as an integral part of an overall control loop utilizing real-time process data from the sensor groups to make production decisions (stop production and repair machine, continue and warn of anticipated problems, queue for repairs, etc.). This model has been successfully used and deployed in the CAFE Project. The economic model was one of seven (see Fig. 1) elements critical in developing an investment strategy. It has been successfully used in guiding the R and D activities on the CAFE Project, suspending activities on three new sensor technologies, and continuing development o f two others. The model has also been used to justify the development of a new prognostic approach for diagnosing machine health using COTS equipment and a new algorithmic approach. maintaining current operations and allows for a method …

Fernald is returning to the basics of interpersonal communication as a cornerstone of its public involvement program. The guiding premise behind this concept is the belief that face-to-face interaction between people is more likely to build trust and confidence than public meetings, news releases and other traditional public information techniques. A network of project spokespersons, called ``envoys,`` is being organized to develop person-to-person relationships with people interested in the future of Fernald. To support this approach, public affairs personnel are adopting roles as management consultants and communications coaches in addition to serving in their traditional role as public information specialists. Early observations seem to show signs of improvement in the level of public trust in Fernald decision-makers.

If the correct interpretation of the Super-Kamiokande atmospheric neutrino data is {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillation, the contained data sample should already have more than 10 {tau} appearance events. We study the challenging task of detecting the {tau}, focusing on the decay chain {tau}{sup {+-}} {yields} {rho}{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup 0} in events with quasi-elastic {tau} production. The background level, which is currently quite uncertain because of a lack of relevant neutral current data, can be measured by the near detector in the K2K experiment. Our estimates of the background suggest that it may be possible to detect {tau} appearance in Super-Kamiokande with 5-10 years of running.

{sup 139}La NQR studies in lightly doped La{sub 2}Cu{sub 1-x}Li{sub x}O{sub 4} and La{sub 1.8-x}Eu{sub 0.2}Sr{sub x}CuO{sub 4} are reviewed. A strong enhancement of the {sup 139}La relaxation rate with a peak accompanied by a sudden increase of the local field at low T has been observed similarly to La{sub 2-x}Sr{sub x}CuO{sub 4}. The anomalous magnetic properties are discussed in the light of the microscopic segregation of doped holes into hole-rich domain walls separating undoped AF domains.

The 1997 international Dirac II Series held at Los Alamos National Laboratory involved low temperature electrical transport and optical experiments in magnetic fields exceeding 800%, produced by explosive flux compression using Russian MC-1 generators. An overview of the scientific and technical advances achieved in this Series is given, together with a strategy for future work in this challenging experimental environment. A significant outcome was achieved in transport studies of microfabricated thin-film YBCO structures with the magnetic field in the CuO plane. Using a GHz transmission line technique at an ambient temperature of 1.6 K, an onset of dissipation was observed at 150 T (a new upper bound for superconductivity in any material), with a saturation of resistivity at 240 T. Comparison with the Pauli limit expected at B=155 T in this material suggests that the critical field in this geometry is limited by spin paramagnetism. In preparation for a Diract III series, a systematic temperature-dependent transport study of YBCO using in-plane magnetic fields of 150 T generated by single-turn coils, at temperatures over the range 10-100 K, has been undertaken in collaboration with the Japanese Megagauss Laboratory. The objective is to map out the phase diagram for this geometry, which …

Intracellular calcium is sequestered in closed membranes such as the sarcoplasmic or endoplasmic reticula and released at discretely distributed protein/receptor channels. The release kinetics can result in the propagation of waves of elevated calcium concentration. The main physical processes are reactions at the release sites and diffusion between the sites. The theory of chemical wave propagation in reaction-diffusion systems is in large part devoted to the study of systems in which there are no extrinsic inhomogeneities. The discrete distribution of the release sites plays a key role in determining the nature of the propagating wave. The authors analyze some simple reaction-diffusion models in order to elucidate the role of discreteness for chemical wave propagation.