A number of compute codes have been modified or developed, both main-frame and PC. Seven codes, of which three are discussed in some detail. The later are: a controller-driven, double-precision version of the coupled-channel code ECIS; the latest version of STAPRE, a precompound plus Hauser-Feshbach nuclear reaction code; and NUSTART, a PC code that analyzes large sets of discrete nuclear levels and the multipole transitions among them. All main-frame codes are now being converted to the UNICOS operating system.

The Booster synchrotron at Brookhaven National Laboratory has been incorporated into the accelerator chain at the Alternating Gradient Synchrotron (AGS) complex. After a successful first commissioning effort in the spring of 1991, the Booster has been part of this year`s silicon, gold and proton physics runs. After a brief review of the Booster design goals, and of the early commissioning, this paper will summarize this year`s activities.

The Booster synchrotron at Brookhaven National Laboratory has been incorporated into the accelerator chain at the Alternating Gradient Synchrotron (AGS) complex. After a successful first commissioning effort in the spring of 1991, the Booster has been part of this year's silicon, gold and proton physics runs. After a brief review of the Booster design goals, and of the early commissioning, this paper will summarize this year's activities.

It has been demonstrated that fast-neutron irradiation produces significant hardening in simple Fe-(3-18)Cr binary alloys irradiated to about 35 dpa in the temperature range 365 to 420{degrees}C, whereas irradiation at 574{degrees}C produces hardening only for 15% or more chromium. The irradiation-induced changes in tensile properties are discussed in terms of changes in the power law work-hardening exponent. The work-hardening exponent of the lower chromium alloys decreased significantly after low-temperature irradiation ({le} 420{degrees}C) but increased after irradiation at 574{degrees}C. The higher chromium alloys failed either in cleavage or in a mixed ductile/brittle fashion. Deformation microstructures are presented to support the tensile behavior.

It has been demonstrated that fast-neutron irradiation produces significant hardening in simple Fe-(3-18)Cr binary alloys irradiated to about 35 dpa in the temperature range 365 to 420[degrees]C, whereas irradiation at 574[degrees]C produces hardening only for 15% or more chromium. The irradiation-induced changes in tensile properties are discussed in terms of changes in the power law work-hardening exponent. The work-hardening exponent of the lower chromium alloys decreased significantly after low-temperature irradiation ([le] 420[degrees]C) but increased after irradiation at 574[degrees]C. The higher chromium alloys failed either in cleavage or in a mixed ductile/brittle fashion. Deformation microstructures are presented to support the tensile behavior.

A pulse stretcher has been designed for the LLNL sodium guide star experiment to lower the laser flux and avoid saturation effects. The optical design, mechanical layout and wavefront error analysis are presented.

In this kinetic study of (1) the reaction of CH{sub 3} radicals with H{sub 2} and (2) the thermal dissociation of methane, primary product H atoms were monitored directly using the sensitive atomic resonance absorption detection technique. The detection limit for the (H) was about 3{times}10{sup 10} atoms cm{sup {minus}3}. Rate constants for both reactions were obtained under pseudo-first-order conditions. In addition, computer simulations verified that kinetic complications were avoided. For the reaction of CH{sub 3}+H{sub 2}, experiments were performed using either acetone or ethane to generate CH{sub 3} radicals rapidly by thermal dissociation in argon. Twenty-four experiments were performed over the temperature range 1346K to 1793K and a rate constant expression derived using linear least-squares analysis: k{sub {minus}2}(T) = (6.0{plus minus}0.7){times}10{sup {minus}12} exp ({minus}5920{plus minus}190K/T) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. 46 refs., 5 figs., 5 tabs.

In this kinetic study of (1) the reaction of CH{sub 3} radicals with H{sub 2} and (2) the thermal dissociation of methane, primary product H atoms were monitored directly using the sensitive atomic resonance absorption detection technique. The detection limit for the [H] was about 3{times}10{sup 10} atoms cm{sup {minus}3}. Rate constants for both reactions were obtained under pseudo-first-order conditions. In addition, computer simulations verified that kinetic complications were avoided. For the reaction of CH{sub 3}+H{sub 2}, experiments were performed using either acetone or ethane to generate CH{sub 3} radicals rapidly by thermal dissociation in argon. Twenty-four experiments were performed over the temperature range 1346K to 1793K and a rate constant expression derived using linear least-squares analysis: k{sub {minus}2}(T) = (6.0{plus_minus}0.7){times}10{sup {minus}12} exp ({minus}5920{plus_minus}190K/T) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. 46 refs., 5 figs., 5 tabs.

We are building a 4.7 Tesla-meter room temperature solenoid to be installed in a 10-foot long AGS straight section. This experiment will test the idea of using a partial snake to correct all depolarizing imperfection resonances and also test the feasibility of betatron tune jump in correction intrinsic resonances in the presence of a partial snake.

This paper examines the evolution of modeling on greenhouse as emissions. The paper briefly highlights the origins and early efforts to model greenhouse gas emissions, efforts subsequent to 1988, and the shape of the next generation of greenhouse gas emissions models. Particular emphasis is placed on the author`s own contributions, including the Edmonds-Reilly Model and the second generation model.

This paper examines the evolution of modeling on greenhouse as emissions. The paper briefly highlights the origins and early efforts to model greenhouse gas emissions, efforts subsequent to 1988, and the shape of the next generation of greenhouse gas emissions models. Particular emphasis is placed on the author's own contributions, including the Edmonds-Reilly Model and the second generation model.

This workshop was designed to bring together a group of scholars, primarily from the social sciences, to explore research that might help in dealing with global climate change. To illustrate the state of present understanding, it seemed useful to focus this workshop on three broad questions that are involved in coping with climate change. These are: (1) How can the anticipated economic costs and benefits of climate change be identified; (2) How can the impacts of climate change be adjusted to or avoided; (3) What previously studied models are available for institutional management of the global environment? The resulting discussions may (1) identify worthwhile avenues for further social science research, (2) help develop feedback for natural scientists about research information from this domain needed by social scientists, and (3) provide policymakers with the sort of relevant research information from the social science community that is currently available. Individual papers are processed separately for the database.

The quantum mechanical AM1 and CNDO/S3 models were used to examine the effect of isoelectronic substitutions on the conformation, electronic structure, and optical absorption spectra for a series of aromatic polyimides. An analysis of the geometric changes at the substitution site and its effect on the electronic structure allowed for the prediction of changes in the ICT band of the optical absorption spectra.

Two independent high-resolution moisture-sensing techniques, x-ray absorption and light transmission, have been developed for use in two-dimensional, thin-slab experimental systems. The techniques yield full-field measurement capabilities with exceptional resolution of moisture content in time and space. These techniques represent powerful tools for the experimentalist to investigate processes governing unsaturated flow and transport through fractured and nonfractured porous media. Evaluation of these techniques has been accomplished by direct comparison of data obtained by means of the x-ray and light techniques as well as comparison with data collected by gravimetric and gamma-ray densitometry techniques. Results show excellent agreement between data collected by the four moisture-content measurement techniques. This program was established to support the Yucca Mountain Site Characterization Project.

The angular resolution of long-exposure images from ground-based telescopes equipped with laser guide star adaptive optics systems is fundamentally limited by the the accuracy with which the tip-tilt aberrations introduced by the atmosphere can be corrected. Assuming that a natural star is used as the tilt reference, the residual error due to tilt anisoplanatism can significantly degrade the long-exposure resolution even if the tilt reference star is separated from the object being imaged by a small angle. Given the observed distribution of stars in the sky, the need to find a tilt reference star quite close to the object restricts the fraction of the sky over which long-exposure images with diffraction limited resolution can be obtained. In this paper, the authors present a comprehensive performance analysis of tip-tilt compensation systems that use a natural star as a tilt reference, taking into account properties of the atmosphere and of the Galactic stellar populations, and optimizing over the system operating parameters to determine the fundamental limits to the long-exposure resolution. Their results show that for a ten meter telescope on Mauna Kea, if the image of the tilt reference star is uncorrected, about half the sky can be imaged in the V …

This volume includes some recent additions to original material prepared for the Princeton International Workshop on the Physics of Compressible Turbulent Mixing, held in 1988. Workshop participants were asked to emphasize the physics of the compressible mixing process rather than measurement techniques or computational methods. Actual experimental results and their meaning were given precedence over discussions of new diagnostic developments. Theoretical interpretations and understanding were stressed rather than the exposition of new analytical model developments or advances in numerical procedures. By design, compressibility influences on turbulent mixing were discussed--almost exclusively--from the perspective of supersonic flow field studies. The papers are arranged in three topical categories: Foundations, Vortical Domination, and Strongly Coupled Compressibility. The Foundations category is a collection of seminal studies that connect current study in compressible turbulent mixing with compressible, high-speed turbulent flow research that almost vanished about two decades ago. A number of contributions are included on flow instability initiation, evolution, and transition between the states of unstable flow onset through those descriptive of fully developed turbulence. The Vortical Domination category includes theoretical and experimental studies of coherent structures, vortex pairing, vortex-dynamics-influenced pressure focusing. In the Strongly Coupled Compressibility category the organizers included the high-speed turbulent flow investigations …

The primary objective of this METC project is to established practical, durable components compatible with clean coal slurry fuel and capable of low emissions. The components will be integrated into a coal power system for a 100-hr proof-of-concept test. The goal of this program is to advance the stationary coal-fueled diesel engine to the next plateau of technological readiness, and thus provide the springboard to commercialization.

The primary objective of this METC project is to established practical, durable components compatible with clean coal slurry fuel and capable of low emissions. The components will be integrated into a coal power system for a 100-hr proof-of-concept test. The goal of this program is to advance the stationary coal-fueled diesel engine to the next plateau of technological readiness, and thus provide the springboard to commercialization.

The Clear Lake area is well known for anomalous heat flow, thermal springs, hydrothermal mineral deposits, and Quaternary volcanism. These factors, along with the apparent lack of a large reservoir of geothermal fluid north of Collayomi fault make the Clear Lake area an attractive target for hot dry rock (HDR) geothermal development. Petrologic considerations provide some constraints on site selection for HDR development. Spatial and temporal trends in volcanism in the Coast Ranges indicate that magmatism has migrated to the north with time, paralleling passage of the Mendocino triple junction and propagation of the San Andreas fault. Volcanism in the region may have resulted from upwelling of hot asthenosphere along the southern margin of the subducted segment of the Gorda plate. Spatial and temporal trends of volcanism within the Clear Lake volcanic field are similar to larger-scale trends of Neogene volcanism in the Cost Ranges. Volcanism (especially for silicic compositions) shows a general migration to the north over the {approximately}2 Ma history of the field, with the youngest two silicic centers located at Mt. Konocti and Borax Lake. The Mt. Konocti system (active from {approximately} 0.6 to 0.3 Ma) was large and long-lived, whereas the Borax Lake system is much …

The quantum mechanical AM1 and CNDO/S3 models were used to examine the effect of isoelectronic substitutions on the conformation, electronic structure, and optical absorption spectra for a series of aromatic polyimides. An analysis of the geometric changes at the substitution site and its effect on the electronic structure allowed for the prediction of changes in the ICT band of the optical absorption spectra.

A hybrid smoothing algorithm is described that smooths first in time and then in frequency. The time-frequency smoothing algorithm is designed to compute estimates of the cyclic (cross) spectrum along lines of constant cycle frequency. A variation on the algorithm, one that incorporates the One Bit Spectral Correlation Algorithm (OBSCA), is also described. A simulation study is presented that evaluates the algorithms.

The interface between mathematics and biology has long been a rich area of research, with mutual benefit to each supporting discipline. Traditional areas of investigation, such as population genetics, ecology, neurobiology, and 3-D reconstructions, have flourished, despite a rather meager environment for the funding of such work. In the past twenty years, the kind and scope of such interactions between mathematicians and biologists have changed dramatically, reaching out to encompass areas of both biology and mathematics that previously had not benefited. At the same time, with the closer integration of theory and experiment, and the increased reliance on high-speed computation, the costs of such research grew, though not the opportunities for funding. The perception became reinforced, both within the research community and at funding agencies, that although these interactions were expanding, they were not doing so at the rate necessary to meet the opportunities and needs. A workshop was held in Washington, DC, between April 28 and May 3, 1990 which drew together a broadly based group of researchers to synthesize conclusions from a group of working papers and extended discussions. The result is the report presented here, which we hope will provide a guide and stimulus to research in …

The interface between mathematics and biology has long been a rich area of research, with mutual benefit to each supporting discipline. Traditional areas of investigation, such as population genetics, ecology, neurobiology, and 3-D reconstructions, have flourished, despite a rather meager environment for the funding of such work. In the past twenty years, the kind and scope of such interactions between mathematicians and biologists have changed dramatically, reaching out to encompass areas of both biology and mathematics that previously had not benefited. At the same time, with the closer integration of theory and experiment, and the increased reliance on high-speed computation, the costs of such research grew, though not the opportunities for funding. The perception became reinforced, both within the research community and at funding agencies, that although these interactions were expanding, they were not doing so at the rate necessary to meet the opportunities and needs. A workshop was held in Washington, DC, between April 28 and May 3, 1990 which drew together a broadly based group of researchers to synthesize conclusions from a group of working papers and extended discussions. The result is the report presented here, which we hope will provide a guide and stimulus to research in …

This is a review on the use of Tandem electrostatic accelerators for injection and filling of synchrotrons to accelerate intense beams of heavy-ions to relativistic energies. The paper emphasizes the need of operating the Tandems in pulsed mode for this application. It has been experimentally demonstrated that at the present this type of accelerators still provides the most reliable and best performance.