A summary of the work recently carried out on the morphotropic phase boundary (MPB) of PZT is presented. By means of x-ray powder diffraction on ceramic samples of excellent quality, the MPB has been successfully characterized by changing temperature in a series of closely spaced compositions. As a result, an unexpected monoclinic phase has been found to exist in between the well-known tetragonal and rhombohedral PZT phases. A detailed structural analysis, together with the investigation of the field effect in this region of compositions, have led to an important advance in understanding the mechanisms responsible for the physical properties of PZT as well as other piezoelectric materials with similar morphotropic phase boundaries.

Visibility and radioactivity control in the fuel component storage and disassembly basins at the Savannah River Plant are maintained with a newly developed purification system. Experimental work was performed to develop the application of sand filters to operate at high flow rates with an effluent turbidity below 0.1 JTU squared. Filtration efficiency of SRP sand filters is dependent on the characteristics of the solids in the feed water and the degree to which filterability can be improved by addition of coagulant aids. It is independent of flow up to flow rates of 15 gpm/square feet (higher flow rates have not been tested). Effluent turbidity remains below 0.1 JTU with no indication of breakthrough. Total water throughput is dependent on the amount of solids removed and is independent of flow rate and concentration of solids.

Immobilization of high-level radioactive waste (HLW) in borosilicate glass is acknowledged world-wide as an acceptable method for preparing HLW for geologic disposal. A waste acceptance process is underway in the United States that will provide specifications and procedures for waste producers well in advance of the availability of a federal repository. Extensive experimental data and rigorous quality assurance and control for plant operation are expected to provide convincing evidence that borosilicate glass waste forms produced in the vitrification plants meet the specifications and can be disposed of safely in a geologic repository.

The VARIANT-K and DIF3D-K nodal spatial kinetics computer codes have been coupled to the SAS4A and SASSYS-1 liquid metal reactor accident and systems analysis codes. SAS4A and SASSYS-1 have been extended with the addition of heavy liquid metal (Pb and Pb-Bi) thermophysical properties, heat transfer correlations, and fluid dynamics correlations. The coupling methodology and heavy liquid metal modeling additions are described. The new computer code suite has been applied to analysis of neutron source and thermal-hydraulics transients in a model of an accelerator-driven minor actinide burner design proposed in an OECD/NEA/NSC benchmark specification. Modeling assumptions and input data generation procedures are described. Results of transient analyses are reported, with emphasis on comparison of P1 and P3 variational nodal transport theory results with nodal diffusion theory results, and on significance of spatial kinetics effects.

This paper describes a mobile analyzer for sulfur hexafluoride, an atmospheric tracer. A commercial instrument is used on-board a moving vehicle to measure tracer concentrations in the parts per trillion (ppt) range. This instrument provides rapid, in-the-field data at minimum cost.

This paper discusses some of the metal hydride and intermetallic compounds which readily absorb the hydrogen gas by a simple contact to form metal hydrides. Metal hydrides have several important properties for the hydrogen isotope separation.

There were 90 papers presented at the Conference in the category of Technology and Power Plants accounting for about 25% of the total number of contributions. As was the case at the previous meeting, a large number of papers dealt with the ITER-Engineering Design Activity (EDA) and ITER technology R&D. In the author's opinion, the rapid progress made during the ITER EDA extension on the completion of the new ITER-FEAT design and its physics and technology R&D validation stands out as the highlight of the meeting. Steady progress is being made on several other technology fronts as well. The results point towards emerging research trends in the following areas: steady-state operation with advanced performance and the increasingly important role of enabling technologies in achieving this goal, advanced, high-performance, environmentally attractive materials for the fusion energy goal, reactor and near-term applications studies that exploit advances both in the physics and technology fronts for lower cost of electricity and improved safety and environmental features, and socioeconomic studies that are helping to promote the attractive features of fusion and its public acceptance. The remaining sections of this paper are organized along the lines of these major themes; namely, ITER EDA Design, ITER Technology …

Tensile creep studies were carried out to evaluate the creep performance of AS800 silicon nitride samples extracted from the surface and bulk regions of as-processed billets at 1350 C in air. The objective of this study was to understand the creep properties of the silicon nitride in the as-processed surface region and determine if they are comparable to those obtained from the bulk region. The results indicated that samples from the as-processed surface region exhibited higher creep rates and shorter lifetimes as compared with those obtained from the bulk region. The poor creep performance of material from the as-processed surface region was due to the higher content of glassy phase enriched with oxygen and sintering additive elements.

A four-channel surface acoustic wave (SAW) chemical sensor array with associated RF electronics is monolithically integrated onto one GaAs IC. The sensor operates at 690 MHz from an on-chip SAW based oscillator and provides simple DC voltage outputs by using integrated phase detectors. This sensor array represents a significant advance in microsensor technology offering miniaturization, increased chemical selectivity, simplified system assembly, improved sensitivity, and inherent temperature compensation.

In order to investigate the feasibility for high-efficiency supercritical-water-cooled nuclear reactors, a study of radiation chemistry in supercritical water has been undertaken. Preliminary results in measurement of the optical absorption of the hydrated electron are reported, and compared with recent anion cluster data.

In this report, we present the use of temperature programmed reaction/decomposition (TPR) in the isoconversion mode to measure outgassing kinetics and to make kinetic prediction concerning hydrogen release from the polycrystalline LiH/LiOH system in the absence of any external H{sub 2}O source.