Physical Sciences and Mathematics Commons^™

Onset Of Convection For Autocatalytic Reaction Fronts In A Vertical Slab, J. Huang, D. A. Vasquez, Boyd F. Edwards, P. Kolodner

All Physics Faculty Publications

A fully three-dimensional linear stability analysis shows that ascending autocatalytic reaction fronts in vertical slabs are unstable to convection for large-wavelength perturbations at all finite values of the dimensionless driving parameter S=δga³/νD_C. This parameter involves a fractional density difference δ between the unreacted and reacted fluids, the acceleration of gravity g, the slab width a, the kinematic viscosity ν, and the catalyst molecular diffusivity D_C. Buoyancy dominates over the competing curvature dependence of the front velocity in a band 0c of unstable dimensionless wave numbers, with q_c→S/24 as S→0 and q_{c …}

Canyonlands National Park And Orange Cliffs Unit Of Glen Canyon National Recreation Area, Environmental Assessment For Backcountry Management Plan, Canyonlands National Park, Glen Canyon National Recreation Area

All U.S. Government Documents (Utah Regional Depository)

Whether on foot. bicycle. horseback. or in vehicles, most visitors come to Canyonlands National

Park (Canyonlands) to experience solitude or to "get away from people." Yet visitation to

Canyonlands has risen exponentially over the past five years (Figures I and 2). Visitation is expected to continue to rise. As a function of this increase in number of visitors, adverse impacts to Canyonlands' resources have increased and the visitors' ability to find solitude has decreased. Since the mandate of the National Park Service (NPS) is to balance visitor access

to the parks with preservation and protection of natural and cultural resources, …

Precipitation Gauge Testing On The Wasatch Plateau, Utah, During Early 1993, United States Department Of The Interior, Bureau Of Reclamation

Meterology

The Bureau of Reclamation performed an independent evaluation of an ETI (Electronic Techniques, Inc.) precipitation gauge at the High Altitude Site on the western slope of the Wasatch Plateau in central Utah. The ETI gauge could provide a desirable alternative to conventional recording gauges in several applications, including evaluation of cloud seeding projects, if it performs as advertised. The testing program was intended to determine its performance in a winter mountain environment. The ETI precipitation gauge proved to be reliable from time of installation in late November 1992 until removal in late March 1993. The only problem found was an …

Convective Turing Patterns, D. A. Vasquez, J. W. Wilder, Boyd F. Edwards

All Physics Faculty Publications

Turing patterns involve regions of different chemical compositions which lead to density gradients that, in liquids, are potentially unstable hydrodynamically. Nonlinear hydrodynamics coupled with a model of Turing pattern formation show that convection modifies and coexists with some Turing patterns and excludes others, and thereby plays a significant role in pattern selection.

New Singularity In Anisotropic, Time-Dependent Solutions To Maximally Gauss-Bonnet Extended Gravity, T. Kitaura, James Thomas Wheeler

All Physics Faculty Publications

Among the solutions for anisotropic, time-dependent, maximally Gauss-Bonnet extended gravity, we find a class of curvature singularities for which the metric components remain finite. These new singularities therefore differ in type from the standard Kasner-like divergences expected for this class of theories. We study perturbative solutions near the singularity and show that there exist solutions with timelike paths that reach the singularity in finite proper time. Solving the equation of geodesic deviation in the same approximation, we show that the comoving coordinate system does not break down at the singularity. A brief classification of the corresponding singularity types in Robertson-Walker …

Record Of Decision Utah Power & Light/American Barrel Site Salt Lake City, Utah, United States Environmental Protection Agency

All U.S. Government Documents (Utah Regional Depository)

This decision document presents the selected remedial action for the Utah Power & Light American Barrel Site in Salt Lake City, Utah, which was chosen in accordance with the requirements of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended by Superfund Amendments and Reauthorization Act of 1986 (SARA), and, to the extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). This decision is based on the administrative record for this site. The Utah Department of Environmental Quality concurs with the remedy selected by the U.S. Environmental Protection Agency (EPA).

Ionicity Of Alkali Metal Adsorbates, Reply, D. Mark Riffe, G. K. Wertheim, P. H. Citrin

All Physics Faculty Publications

A Comment on the Letter by D. M. Riffe et al. Phys. Rev. Lett. 64, 571 (1990).

Symmetries Of The Einstein Equations, Ian M. Anderson, C. Torre

Mathematics and Statistics Faculty Publications

We classify all generalized symmetries of the vacuum Einstein equations in four spacetime dimensions. They consist of constant scalings of the metric, and of the infinitesimal action of generalized spacetime diffeomorphisms. Our results rule out a large class of possible ‘‘observables’’ for the gravitational field, and suggest that the vacuum Einstein equations are not integrable.

National Wetlands Inventory Maps, Logan, (Ogden Nw) Ut, Usfws, United States Department Of The Interior, Fish And Wildlife Service

Water

This document was prepared primarily by stereoscopic analysis of high altitude aerial photographs. Wetlands were identified on the photographs based on vegetation, visible hydrology, and geography in accordance with classification of Wetland and Deepwater Habitats of the United States (FWS/OBS-79/31 December 1979). The aerial photographs typically reflect conditions during the specific year and season when they were taken. In addition there is a margin of error inherent in the use of the aerial photographs.

Proceedings Of The Fourth Western Black Bear Workshop, United States Department Of The Interior, National Park Service

Wildlife Conservation and Management

The status of black bears in North America ranges from pest to threatened. The species appears relatively secure throughout most parts of its range except the southeastern coastal plain; in this region a number of disjunct populations exist on primarily publicly owned lands. Concern over the status of Ursus americanus luteolus led to a petition to list this subspecies under the Endangered Species Act. The Endangered Species Act is arguably the most important wildlife legislation in recent years. However, applying this valuable, but young, untested, and evolving legislation to the black bear subspecies is judged unwarranted and premature because of …

Modification Of The Eikonal Relation For Chemical Waves To Include Fluid Flow, J. W. Wilder, D. A. Vasquez, Boyd F. Edwards

All Physics Faculty Publications

Propagating wave fronts resulting from autocatalytic chemical reactions have been the focus of much recent research. For the most part, the hydrodynamics resulting from such reactions has been neglected. In this work, a relation is derived for the normal speed of a propagating wave front as a function of the local curvature when fluid motion is allowed. This ‘‘eikonal’’ equation is a generalization of one which was derived in the absence of fluid flow. It is also shown that small variations in the fluid density due to the chemical reaction do not change the form of the relation.

Preliminary Public Health Assessment: Petrochem Recycling Corporation/Ekotek Salt Lake City, Salt Lake County, Utah, Agency For Toxic Substances And Disease Registry, Divisoin Of Health Assessment And Consultation

All U.S. Government Documents (Utah Regional Depository)

The Petrochem/EkoTek site was operated by several owners as a refinery from 1953 until 1978 and as a hazardous waste storage treatment facility and a petroleum recycling facility from 1978 through 1988. Removal of essentially all petroleum products and hazardous wastes in tanks and drums was accomplished from 1988 - 1991. The process that will lead to the complete clean-up of the facility is ongoing. The site was added to the National Priorities List (NPL) in October 1992. Exposure of humans to contaminants in soil and air is thought to have occurred near Petrochem. The source(s) of those contaminants in …

Evidence Of Preferential Directions For Gravity Wave Propagation Due To Wind Filtering In The Middle Atmosphere, Michael J. Taylor, E. H. Ryan, T. F. Tuan, R. Edwards

All Physics Faculty Publications

All-sky TV images of wave structure in the near-infrared hydroxyl (OH) nightglow emission were recorded over a 3-month period during May, June, and July 1988 from a high-altitude site at the Mountain Research Station (40.0° N, 105.6° W, 3050 m), near Nederland, Colorado. Well-defined, coherent wave patterns associated with the passage of short period (<1 hour) gravity waves were observed on a total of 22 occasions. The wave motions exhibited similar spatial and temporal properties during each month but a distinct tendency for northward propagation (68% of the wave azimuths within ± 40.0° N), with some eastward motion in May and June, was observed throughout the campaign. Although it is theoretically well known that upward propagating gravity waves can be blocked at a critical layer produced by the interaction of the waves with the horizontal background wind, observational evidence of this phenomenon is rare. To investigate the possibility that the asymmetry in the wave propagation directions was caused by the critical layer, a model based on mean climatological background winds and numerical tidal wave modes valid for any mid-latitude site and time of the year was constructed to show the regions forbidden to upward gravity wave propagation from critical layer theory. These “blocking diagrams” which vary with height and time were constructed for the OH altitude (∼87 km) for the present paper. Comparison of the predicted (i.e., least restricted) and the observed directions of the wave motion show almost complete agreement. This suggests that middle atmospheric winds can play an important role in determining the flux and the azimuthal distribution of short-period waves reaching the upper atmosphere.

Ta(110) Surface And Subsurface Core-Level Shifts And 4f7/2 Lineshapes, D. Mark Riffe, G. K. Wertheim

All Physics Faculty Publications

High-resolution 4f core-level spectra of the Ta(110) surface region have been obtained at 80 and 300 K with 70- and 100-eV synchrotron radiation. The data show that the subsurface core-level binding-energy shift (compared to deeper-lying atoms) for a close-packed bcc(110) surface can be substantial: 65±15 meV for the first underlayer atoms of Ta(110). The surface core-level shift is 360±12 meV at 80 K and decreases by 13±2 meV at 300 K. Final-state screening in both the bulk and surface layers is well described by a constant singularity index of 0.133±0.012. An enhanced phonon broadening at the surface corresponds to a …

Problem Analysis For The Vegetation Diversity Project, David A. Pyke, Michael M. Borman, U.S. Department Of The Interior, Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

Management of the majority of public rangeland in the Great Basin and Columbia-Snake River Plateau falls under the authority of the Bureau of Land Management. The flora of this land ranges from highly diverse native plant communities to deteriorated lands dominated by exotic annuals. Approximately nine percent of the BLM’s 78 million acres of public land in this region is degraded to such a degree that changes in land management alone will not result in significant improvement. The BLM intends to restore native plant communities on these deteriorated lands, but current revegetation techniques used to establish introduced perennial grasses are …

Remedial Action Plan For The Codisposal And Stabilization Of The Monument Valley And Mexican Hat Uranium Mill Tailings At Mexican Hat, Utah, Uranium Mill Tailings Remedial Action Project Office, Albuquerque Operations Office, Department Of Energy

All U.S. Government Documents (Utah Regional Depository)

The Mexican Hat tailings site is in the San Juan County, Utah, two road miles southwest of the town of Mexican Hat on the Navajo Reservation. The Navajo community of Halchita is approximately 0.5 mile southwest of the site. The mill at the Mexican Hat site was operated from 1957 to 1965 by Texas-Zinc Minerals Corporation and the Atlas Corporation. Originally, two irregularly shaped tailings piles were located in the northeastern portion of the site. They occupied approximately 69 acres of the 235-acre designated site and contained approximately 2,575,000 cubic yards (cy) of tailings. The total amount of materials, including …

Vascular Flora And Vegetation Of Capitol Reef National Park, Utah, Kenneth D. Heil, J. Mark Porter, Rich Fleming, William H. Romme

Elusive Documents

No abstract provided.

Preserves At Risk: An Investigation Of Resource Management Strategies, Implications And Opportunities, R. J. Lilieholm

Elusive Documents

Human activities already threaten the globe's physical and biological systems. Worldwide, species extinction rates are estimated to be one thousand times what they would be in the absence of human activity (Wilson 1988). Raven (1988) estimates that 25% of the world's plant and animal species existing in 1985 may be extinct by 2015, with most extinctions occurring in tropical regions. While these extinction rates are staggering, global warming would greatly accelerate extinction rates that some scientists believe may already exceed those accompanying the decline of the dinosaurs 65 million years ago (Wolf 1987).

An Empirical Model Of Gastric Evacuation Rates For Fish And An Analysis Of Digestion In Piscivorous Brown Trout, E. He, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

The gastric evacuation rates of brown trout Salmo trutta (0.9–1.6 kg) feeding on fingerling rainbow trout Oncorhynchus mykiss (3.5–7.6 g) were measured in the laboratory at five temperatures (4.5, 9.0, 14.0, 19.0, and 22.5°C). Instantaneous gut evacuation rates (Re) increased exponentially with temperature (T): Re = 0.053se^0.073T, r^2 = 0.98; they varyied from 7%sh^–1 at 4.5°C to 29%sh^–1 at 22.5°C. Linear regressions described the relationship between time and qualitative measures of fish digestion, thus allowing investigators to determine how long an ingested fish would be identifiable at different temperatures. An analysis of published evacuation rates (N = 121) of 22 …

Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Historically, thousands of Snake River Sockeye salmon returned to the Sawtooth Valley to spawn. Evermann (1896) reported that the Sawtooth Valley Lakes were teeming with red fish. Bjornn (196~) estimated that 4,360 sockeye returned to Redfish Lake in 1955. These numbers no longer exist. In the 1980's, less than 50 Snake River sockeye salmon survived to spawn (Bowler 1990). Since 19-90, only 13 sockeye have returned. Because of recent declines, the Shoshone-Bannock Tribes (SBT) petitioned the National Marine Fisheries Service (NMFS-) to list Snake River sockeye as endangered. As a result, Snake River sockeye were listed and the Bonneville Power …

Effects Of Moonlight And Daylight On Hydroacoustic Estimates Of Pelagic Fish Abundance, Chris Luecke, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

To determine how moonlight and daylight affect hydroacoustic estimates of fish abundance, we used a dual-beam transducer and echo integration to survey pelagic fish (primarily Bonneville ciscoes Prosopium gemmifer) in Bear Lake, Utah and Idaho. During the new moon, the fish were dispersed (not schooling) below the thermocline, chiefly at the depths of 10–20 m. At full moon, they were dispersed but much closer to the bottom, where they were difficult to detect. Acoustic estimates offish density and biomass during full moons were approximately 50% of values derived during new moons. A diel survey during a new moon indicated that …

Gravitational Observables And Local Symmetries, Charles G. Torre

All Physics Faculty Publications

Using a recent classification of local symmetries of the vacuum Einstein equations, it is shown that there can be no observables for the vacuum gravitational field (in a closed universe) built as spatial integrals of local functions of Cauchy data and their derivatives.

A First-Principle Derivation Of The High Latitude Total Electron Content Distribution, D. J. Crain, Jan Josef Sojka, Robert W. Schunk, P. H. Doherty, J. A. Klobucher

All Physics Faculty Publications

Calculation of the high-latitude distribution of the vertical total electron content (TEC) is possible using a three-dimensional, time-dependent ionospheric model. Global and local comparisons may be made with observations of TEC. We compare the local diurnal variation of TEC calculated by the model with observations of TEC at Goose Bay, Labrador and Hamilton, Massachusetts. Data from the period of March 1–11, 1989, and monthly averaged data for solar maximum and solar minimum periods are examined. We extend the model to predict diurnal variations of TEC in the polar cap and compare these results with the observed TEC at Thule, Greenland, …

Symmetries Of The Einstein Equations, Charles G. Torre, Ian M. Anderson

All Physics Faculty Publications

We classify all generalized symmetries of the vacuum Einstein equations in four spacetime dimensions. They consist of constant scalings of the metric, and of the infinitesimal action of generalized spacetime diffeomorphisms. Our results rule out a large class of possible ‘‘observables’’ for the gravitational field, and suggest that the vacuum Einstein equations are not integrable.

Final Environmental Impact Statement To Construct And Operate A Facility To Receive, Store, And Dispose Of 11e.(2) Byproduct Material Near Clive, Utah, United States Nuclear Regulatory Commission

Final environmental Impact Statements (UT)

A Final Environmental Impact Statement related to the licensing of Envirocare of Utah, Inc.'s proposed disposal facility in Tooele County, Utah, (Docket No. 40-8989) for byproduct material as defined in Section 11e.(2) of the Atomic Energy Act, has been prepared by the Office of Nuclear Material Safety and Safeguards. This statement describes and evaluates (1) the purpose of and need for the proposed action, (2) alternatives considered, and (3) environmental consequences of the proposed action. The Nuclear Regulatory Commission has concluded that the proposed action evaluated under the National Environmental Policy Act of 1969 and 10 CFR Part 51, is …

Final Environmental Impact Statement North Slope Timber Sale Dixie National Forest

Final environmental Impact Statements (UT)

This Final Environmental Impact Statement describes the analysis for the proposed North Slope Timber Sale. The 1,730 acre proposal area is located on the north slope of Boulder Mountain within the Teasdale Ranger District (Wayne County, Utah). Alternatives were developed for this proposal which respond to issues identified during the scoping and analysis process.

Parameterized Study Of The Ionospheric Modification Associated With Sun-Aligned Polar Cap Arcs, D. J. Crain, Jan Josef Sojka, Robert W. Schunk, Lie Zhu

All Physics Faculty Publications

Sun-aligned (SA) arcs are a prevalent feature of the polar cap ionosphere during northward interplanetary magnetic field conditions. These arcs are, like the auroral arc, a complex electrodynamic system coupling the ionosphere and magnetosphere. The electron precipitation and convection electric field associated with this system modify the polar cap ionospheric plasma distribution. In the past decade, a wealth of observational information has indicated the complexity of these ionospheric modifications, but only a limited number of model studies have been carried out to elucidate the changes associated with SA arcs. In this investigation, an extensive parametric study has been conducted to …

Modeling Polar Cap F-Region Patches Using Time Varying Convection, Jan Josef Sojka, M. D. Bowline, Robert W. Schunk, D. T. Decker, Cesar E. Valladares, R. Sheehand, D. N. Anders, R. A. Heelis

All Physics Faculty Publications

Creation of polar cap F‐region patches are simulated for the first time using two independent physical models of the high latitude ionosphere. The patch formation is achieved by temporally varying the magnetospheric electric field (ionospheric convection) input to the models. The imposed convection variations are comparable to changes in the convection that result from changes in the B_y IMF component for southward interplanetary magnetic field (IMF). Solar maximum‐winter simulations show that simple changes in the convection pattern lead to significant changes in the polar cap plasma structuring. Specifically, in winter, as enhanced dayside plasma convects into the polar …

A Time-Dependent Model Of Polar Cap Arcs, Lie Zhu, Jan Josef Sojka, Robert W. Schunk, D. J. Crain

All Physics Faculty Publications

A two-dimensional time-dependent model of polar cap arcs has been developed. The electrodynamics of the polar cap arcs are treated self-consistently in the frame of the coupled magnetosphere-ionosphere system. The focus of this paper is to introduce the physics and mathematical formulation of the model and describe the features of the spatial structure and temporal evolution of the polar cap arcs. The modeling results indicate that the time constant for the formation of the polar cap arcs is around 10 min. It is found that an initial single-arc precipitation pattern associated with a polar cap arc tends to split into …

Influence Of Horizontal Inhomogeneity In The Ionosphere On The Reflection Of Alfvén Waves, Lie Zhu, Jan Josef Sojka, Robert W. Schunk, D. J. Crain

All Physics Faculty Publications

A study of the reflection of Alfvén waves at a horizontally inhomogeneous ionosphere has been carried out. In this study, the Alfvén speed above the ionosphere is assumed to be uniform and the ionosphere is treated as a height‐integrated conducting slab. Analytical and numerical results indicate that the horizontal nonuniformity of the ionospheric conductivity can lead to a rotation of the reflected wave fields and cause field‐aligned currents that originate in the ionosphere. A strong conductivity nonuniformity in the direction perpendicular to the incident wave field, large Hall to Pedersen conductivity ratios, and low conductivity values lead to a large …