Analytical and finite element method (FEM) simulations of creep in idealized ductile-phase toughened intermetallic composites are described. For these strong-matrix materials, the two types of analyses predict similar time-independent composite creep rates if each phase individually exhibits only steady-state creep. The composite creep rate becomes increasingly higher than that of the monolithic intermetallic as the stress exponent of the intermetallic and the volume fraction and creep rate of the ductile phase increase. FEM analysis shows that the shape of the ductile phase does not affect the creep rate but may affect the internal stress and strain distributions, and thus damage accumulation rates. If primary creep occurs in one or both of the individual phases, the composite also exhibits primary creep. In this case, there can be significant deviations in the creep curves computed by the analytical and FEM models. The model predictions are compared with data for the Nb5Si3/Nb system.

Quality systems development in environmental measurements for compliance with regulatory requirements for nuclear and other contaminants in the environment is one of the major challenges in current technology disciplines. Efforts to fulfill the mission and objectives of funded projects will not be successful on a timely and cost-effective schedule without adequate plans and credible action for the protection of workers, facilities, and the public in environment, safety, and health aspects. This can be accomplished through quality assurance planning and implementation of an effective, controlled environmental measurements program.

A non-destructive analysis technique using a portable, electric ion-tube neutron source (INS) and gamma ray detector has been used to identify the key constituent elements in a number of sealed munitions, and from the elemental makeup, infer the types of agent within each. The high energy (14 MeV) and pulsed character of the neutron flux from an INS provide a method of measuring, quantitatively, the oxygen, carbon, and fluorine content of materials in closed containers, as well as the other constituents that can be measured with low-energy neutron probes. The broad range of elements that can be quantitatively measured with INS-based instruments provides a capability of verifying common munition fills; it provides the greatest specificity of any portable neutron-based technique for determining the full matrix of chemical elements in completely unrestricted sample scenarios. The specific capability of quantifying the carbon and oxygen content of materials should lead to a fast screening technique which, can discriminate very quickly between high-explosive and chemical agent-filled containers.

Among its many unique and precedent-setting provisions, the Chemical Weapons Convention (CWC) includes important requirements for States Parties to protect the public safety and the environment in the course of carrying out the treaty. These obligations will apply to the destruction of chemical weapons, of former chemical weapons production facilities, and to other activities under the Convention such as the verification scheme. This morning, I will briefly discuss the Convention`s safety and environmental obligations, concentrating on their effects in this country as the United States chemical weapons stockpile is destroyed.

Decontamination and dismantlement (D&D) tasks have been successfully completed on Plant 7 at the Fernald Environmental Management Project. The seven story facility was radiologically, chemically, and biologically contaminated. The work involved the D&D work beginning with safe shutdown and gross decontamination, and ended with removal of the structural steel. A series of lessons learned were gained which include use of explosives, bidding tactics, safe shutdown, building decontamination and lockdown, use of seam climbers, etc.

RENi{sub 2}B{sub 2}C (RE=Rare Earth) are quaternary compounds which exhibit a considerable degree of interaction between their superconducting and magnetic properties. The Ho variant is found to become superconducting at {Tc} = 9 K, but anomalous behaviour is observed in the low field magnetic properties at T<7 K (increasing susceptibility with decreasing temperature); at temperatures less than 5.6 K more conventional behaviour is regained. Neutron diffraction measurements demonstrate that at low temperatures (T<5K) the magnetic order consists of ferromagnetic planes antiferromagnetically coupled up the c-axis with a Ho moment of 8.9 {plus_minus}0 0.2 {mu}{sub B} canted at 15{degree}{plus_minus}5 from the a-b plane. At high temperatures (7<T<8.5 K) satellites, together with the principal Bragg reflections, are observed which correspond to a modulation of the magnetic order with a wavelength of {approximately} 136 {Angstrom} up the c-axis. In the intermediate temperature (5<T<7 K) range further Bragg refections become evident. An additional modulation along the a-axis becomes important in this temperature range.

We discuss the role of polarization measurements and scattering amplitudes for elastic nucleon-nucleon processes at high energy. The relative normalization of these amplitudes involves a ``leading order form factor`` which we determine empirically. These amplitudes provide an economical description of a large body of existing data and make some nontrivial predictions for spin observables. In particular, we have investigated cross sections and asymmetry data at large angles (including 90{degrees} c.m.) and the fixed {vert_bar} t {vert_bar}, large s region, dominated by the three-gluon exchange mechanism. Our results indicate that polarization experiments can test basic QCD elements such as helicity conservation, wave function properties and the interplay between various interaction mechanisms. The significance of this analysis will be discussed in terms of specific polarization experiments, which can be performed at Fermilab and Brookhaven (RHIC.AGS).

This article critically examines a two-step solvational model for mathematically describing the spectral properties of the DImroth-Reichardt betaine dye ET in binary aqueous-organic solvent mixures.

Using a recently developed spin-polarized, fully relativistic, multiple scattering approach based on the layer KKR Green function method, we have reproduced the Fe 3p angle-resolved soft x-ray photoemission spectra and analyzed the associated large magnetic dichroism effects for excitation with both linearly and circularly polarized light. Comparison between theory and experiment yields a spin-orbit splitting of 1.0--1.2 eV and an exchange splitting of 0.9-- 1.0 eV for Fe 3p. These values are 50--100% larger than those hitherto obtained experimentally.

Seismic evaluations of essential systems and components at Department of Energy (DOE) facilities will be conducted over the next several years. For many of these systems and components, few, if any, seismic requirements applied to the original design, procurement, installation, and maintenance process. Thus the verification of the seismic adequacy of existing systems and components presents a difficult challenge. DOE has undertaken development of the criteria and procedures for these seismic evaluations that will maximize safety benefits in a timely and cost effective manner. As demonstrated in previous applications at DOE facilities and by the experience from the commercial nuclear power industry, use of experience data for these evaluations is the only viable option for most existing systems and components. This paper describes seismic experience data, the needs at DOE facilities, the precedent of application of nuclear power plants and DOE facilities, and the program underway for the seismic verification task ahead for DOE.

Small scale terawatt and soon even petawatt (1000 terawatt) class laser systems are made possible by application of the chirped-pulse amplification technique to solid-state lasers combined with the availability of broad bandwidth materials. These lasers make possible a new class of high gradient accelerators based on the large electric fields associated with intense laser-plasma interactions or from the intense laser field directly. Here, we concentrate on the laser technology to produce these intense pulses. Application of the smallest of these systems to the production of high brightness electron sources is also introduced.

Integrated assessment is an approach that is useful in evaluating the consequences of global climate change. Understanding the consequences requires knowledge of the relationship between land-use change and climate change. Methodologies for assessing the contribution of land-use change to atmospheric CO{sub 2} concentrations are considered with reference to a particular case study area: south and southeast Asia. The use of models to evaluate the consequences of climate change on forests must also consider an assessment approach. Each of these points is discussed in the following four sections.

Feasibility studies and manufacturing experience on the GEM Magnet superconductor are presented, including all components - NbTi strand, cable, conduit manufacture, cable pulling, and aluminum sheath application.

Commercialization of aerogels has been slow due to several factors including cost and manufacturability issues. The technology itself is well enough developed as a result of work over the past decade by an international-community of researchers. Several extensive substantial markets appear to exist for aerogels as thermal and sound insulators, if production costs can keep prices in line with competing established materials. The authors discuss here the elements which they have identified as key cost drivers, and they give a prognosis for the evolution of the technology leading to reduced cost aerogel production.