One of the most challenging aspects of ion beam driven inertial fusion energy is the reliable and efficient generation of low emittance, high current ion beams. The primary ion source requirements include a rise time of order 1-{micro}sec, a pulse width of at least 20-{micro}sec, a flattop ripple of less than 0.1% and a repetition rate of at least 5-HZ. Naturally, at such a repetition rate, the duty cycle of the source must be greater than 10{sup 8} pulses. Although these specifications do not appear to exceed the state-of-the-art for pulsed power, considerable effort remains to develop a suitable high current ion source. Therefore, we are constructing a 500-kV test stand specifically for studying various ion source concepts including surface, plasma and metal vapor arc. This paper will describe the test stand design specifications as well as the details of the various subsystems and components.

As part of the Formerly Utilized Site Remedial Action Program (FUSRAP), the United States Army Corps of Engineers (USACE), Buffalo District, is responsible for overseeing the remediation of several sites within its jurisdiction. FUSRAP sites are largely privately held facilities that were contaminated by activities associated with the nuclear weapons program in the 1940s, 50s, and 60s. The presence of soils and structures contaminated with low levels of radionuclides is a common problem at these sites. Typically, contaminated materials must be disposed of off-site at considerable expense (up to several hundred dollars per cubic yard of waste material). FUSRAP is on an aggressive schedule, with most sites scheduled for close-out in the next couple of years. Among the multitude of tasks involved in a typical remediation project is the need to inform and coordinate with active stakeholder communities, including local, state, and federal regulators.

Methods to determine unsaturated hydraulic properties can exhibit random and non-unique behavior. The authors assess the causes for these behaviors by visualizing micro-scale phase displacement processes during equilibrium retention and transient outflow experiments. They observe that the drainage process is composed of a fast fingering followed by a slower backfilling. The influence of each these processes is controlled by the size and the speed of the applied boundary step, the initial saturation and its structure and by small-scale heterogeneities. Because the mixture of these micro-scale processes yields macro-scale effective behavior, measured unsaturated flow properties are also a function of these controls. These results suggest limitations on the current definitions and uniqueness of unsaturated hydraulic properties.

Neutron inelastic scattering measurements of the polar TO phonon mode in the cubic relaxor Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}, at room temperature, reveal anomalous behavior similar to that recently observed in Pb(Zn{sub 1/3}Nb{sub 2/3}){sub 0.92}Ti{sub 0.08}O{sub 3} in which the optic branch appears to drop precipitously into the acoustic branch at a finite value of the momentum transfer q = 0.2 {angstrom}{sub {minus}1}, measured from the zone center. By contrast, a recent neutron study indicates that PMN exhibits a normal TO phonon dispersion at 800 K. The authors speculate this behavior is common to all relaxor materials, and is the result of the presence of nanometer-scale polarized domains in the crystal that form below a temperature T{sub d}, which effectively prevent the propagation of long wavelength (q = 0) phonons.

The authors have studied the spectral shift of the solvated electron in MeOH/C{sub 2}H{sub 6} mixture using pulse radiolysis. The solvated electrons were formed by ionizing the solution. The spectral shift can be explained in terms of MeOH cluster size formed in the solution. With increasing temperature at constant mole fraction of MeOH, the spectral maximum shifts toward low energy. The width at red side increased with increasing temperature, however, there is no significant changes in the blue side of the spectra with temperature.

Environmental compliance reporting requirements are notoriously complex. This reporting complexity is compounded by organizational and functional complexity at Rocky Mountain Arsenal (RMA), where the Department of the Army has undertaken a multi billion dollar environmental cleanup action. This site is subject to both fixed and contingent federal, state, and local reporting requirements. Management and operation of the site is characterized by numerous organizational layers, and compliance information is generated by many different contractors and subcontractors. This information must be compiled by various managers and reported to either regulators or Department of the Army offices. The RMA Environmental Compliance Office and top-level management must be assured that these reports are being promptly generated and submitted. With over 1,500 individual reporting requirements forecasted for over the next 11 years, the managerial challenge is immense. To facilitate the collation of data and issuance of compliance reports, an intranet-based database is being developed. This database is designed to be available to all personnel with access to the site's environmental compliance intranet. It presents all applicable reporting requirements in an easily sortable format. Information available for each report includes deadlines, report status, recipients, individuals responsible for report generation, and other relevant data fields. Reports can …

Optically generated acoustic waves have been used to temporarily permeate biological cells. This technique may be useful for enhancing transfection of DNA into cells or enhancing the absorption of locally delivered drugs. A diode-pumped frequency-doubled Nd:YAG laser operating at kHz repetition rates was used to produce a series of acoustic pulses. An acoustic wave was formed via thermoelastic expansion by depositing laser radiation into an absorbing dye. Generated pressures were measured with a PVDF hydrophone. The acoustic waves were transmitted to cultured and plated cells. The cell media contained a selection of normally- impermeable fluorescent-labeled dextran dyes. Following treatment with the opto-acoustic technique, cellular incorporation of dyes, up to 40,000 Molecular Weight, was noted. Control cells that did not receive opto-acoustic treatment had unremarkable dye incorporation. Uptake of dye was quantified via fluorescent microscopic analysis. Trypan Blue membrane exclusion assays and fluorescent labeling assays confirmed the vitality of cells following treatment. This method of enhanced drug delivery has the potential to dramatically reduce required drug dosages and associated side effects and enable revolutionary therapies.

The pulse radiolysis technique has been applied to study reactions of ions in supercritical solutions. Evidence for the formation of C{sub 2}O{sub 4}{sup +} has been found in supercritical CO{sub 2}. The rate of the electron transfer reaction from dimethyl aniline to the C{sub 2}O{sub 4}{sup +} was measured over the density range of 0.17--0.7 g/cm{sup 3}. The reaction rate was measured to be close to diffusion-controlled at the lowest density; at higher densities, the rate was considerably below the apparent diffusion-controlled rate. Similar behavior was found for the reaction of the anion (presumably C{sub 2}O{sub 4}{sup {minus}}) with benzoquinone. The reaction of O{sub 2} with C{sub 2}O{sub 4}{sup +} was considerably slower than the expected diffusion-controlled rate.

Characterization data are reported for sodium bonded EBR-II reactor fuel which had been stored underwater in containers since the 1981--1982 timeframe. Ten stainless steel storage containers, which had leaked water during storage due to improper sealing, were retrieved from the ICPP-603 storage basin at the Idaho National Engineering and Environmental Laboratory (INEEL) in Idaho. In the container chosen for detailed destructive analysis, the stainless steel cladding on the uranium alloy fuel had ruptured and fuel oxide sludge filled the bottom of the container. Headspace gas sampling determined that greater than 99% hydrogen was present. Cesium 137, which had leached out of the fuel during the aqueous corrosion process, dominated the radionuclide source term of the water. The metallic sodium from the fuel element bond had reacted with the water, forming a concentrated caustic solution of NaOH.

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.

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.

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.