Digital Commons Network^™

Nitrogen Source And Application Method: Does It Matter?, Gilbert D. Miller, Jay C. Andersen

Archived Natural Resources Publications

Irrigation management has a greater effect on the amount of nitrate that is leached out of the root one than does the type of nitrogen applied.

Mapping Instream Habitat On The San Juan River Using Airborne Videography, Michael J. Pucherelli, William P. Goettlicher, Bureau Of Reclamation, U.S Department Of The Interior

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

Concerns have been raised over the potential impacts of the Animas/LaPlata project and the regulation of Navajo Dam. Flow depletions in the San Juan River may adversely affect the remnant population of the native fish, particularly the endangered Colorado squawfish and the razorback sucker. A multiyear research program is currently being conducted on the San Juan River as a result of a Jeopardy Opinion delivered by the U.S. Fish and Wildlife Service on Animas/LaPlata and the subsequent Reasonable and Prudent Alternative that was accepted. A mulidisciplinary research team composed of representatives from the affected agencies is currently investigating the relationship …

Exact Enumeration And Scaling For Fragmentation Of Percolation Clusters, Boyd F. Edwards, M. F. Gyure, M. V. Ferer

All Physics Faculty Publications

The fragmentation properties of percolation clusters yield information about their structure. Monte Carlo simulations and exact cluster enumeration for a square bond lattice and exact calculations for the Bethe lattice are used to study the fragmentation probability a_s(p) of clusters of mass s at an occupation probability p and the likelihood b_s′s(p) that fragmentation of an s cluster will result in a daughter cluster of mass s′. Evidence is presented to support the scaling laws a_s(p_c)∼s and b_s′s(p_c)=s^-φg(s′/s), with φ=2-σ given by the standard cluster-number scaling …

Can Antibiotic Test Kits Be Useful?, Bart Weimer

Archived Food and Health Publications

Publication discusses whether or not antibiotic test kits are useful and what the various results mean.

Coping At The Crossroads: Societal And Educational Transformation, Glenn E. Baker, Richard A. Boser, Dan L. Householder

Engineering Education Faculty Publications

As the nature of a workforce changes over time, one broadly-defined group of workers diminishes in numbers while another group increases in numbers. For example, during the period 1890-1910, the major proportion of the workforce in the United States shifted from agriculture to industrial production (U.S. Bureau of the Census, 1975). Figure 1 presents the concept. Relentless technological developments gave rise to new job classifications and to increased employment opportunities in industrial production. At the same time, technological developments diminished employment opportunities in another field, in this case, agriculture. Over the long term, then, one might expect that demand for …

The Fairness Factor, Everette E. Dennis, Ted Pease

Journalism and Communication Faculty Publications

As THE FIRST POST-COLD WAR ADMINISTRATION takes office in Washington, there is general agreement that the media will play a significant role in its success or failure. Whether Americans wish President Clinton well or ill, they will all agree on at least one thing: that the media ought to be fair in reporting his efforts.

Hydrodynamic Instability Of Chemical Waves, D. A. Vasquez, J. W. Wilder, Boyd F. Edwards

All Physics Faculty Publications

We present a theory for the transition to convection for flat chemical wave fronts propagating upward. The theory is based on the hydrodynamic equations and the one‐variable reaction‐diffusion equation that describes the chemical front for the iodate–arsenous acid reaction. The reaction term involves the reaction rate constants and the chemical composition of the mixture. This allows the discussion of the effects of the different chemical variables on the transition to convection. We have studied perturbations of different wavelengths on an unbounded flat chemical front and found that for wavelengths larger than a critical wavelength (λ≳λ_c) the perturbations grow …

Proceedings From The 29th Annual Marschall Italian Cheese Seminar, Various Authors

Cheese Industry Conference

Three 375 lb vats of cultured low moisture pan skim Mozzarella cheese were produced from the same batch of standardized milk and rennet, but using three different rod (Lactobacillus bulgaricus - Marschall ProduciS - Thennorod) and coccus (Streptococcus thermophilus - Mar chall Product - Thennococcus) ratios (9R:IC, 5R:5C, and !R:9C). The total volume and total colony fonning units of culture added was kept constant for all ratios (i.e., I 02 ml/375 I b). Cheese was made with the ·'no-brine·· chee e making method using a I06°F (41° ) cook temperature, 6.4 draw pH *whey), 5.25 milling pH, and 135°F (57°C) …

Utah Families- The Issues They Face, Ted W. Warstadt, Larry Forthun

All Archived Publications

With the wide variety of difficulties that our society faces and the limited funding available to address these concerns, it is important to identify and prioritize critical family issues. Because the family is a major contributor to individual and societal development, it is important to focus attention on issues which have a direct impact on family functioning. In identifying issues it is also helpful to understand demographic and geographic influences which may contribute to an individual's perceived urgency of a given issue. This can assist policy makers in their efforts to appropriately allocate limited funds to the best suited and …

Selection And Development Of Replacement Beef Heifers, Norris J. Stenquist, James A. Bennett

Archived Agriculture Publications

Selection, development, management, and nutrition of heifer calves to be used as herd replacements are key factors in maintaining beef herd productivity. A cow/calf producer, to be successful, must have some goals or criterion for heifer selection and development. For practically all Utah cattle production areas, economics dictate that heifers must calve as two-year-olds. Heifers must be properly developed and managed to permit this. The following factors are important: Heifers should 1) become pregnant in the first 25 days of the breeding season, 2) give birth to a live calf with little or no calving difficulty, 3) raise a calf …

Best Management Practices To Minimize Nitrate Leaching For Irrigated Potatoes, Robert W. Hill, Ahmad Y. Ranjha

All Archived Publications

Nitrate nitrogen (N03-N) leaching is becoming an alarming threat to ground water in many areas in the U.S. In one study in North Carolina, over 9000 domestic wells were sampled for nitrate. Over 3 percent (288 wells) contained N03-N at levels exceeding the Environmental Protection Agency (EPA) safe drinking water standard of 10 mgIL (Jennings, et aI., 1991). Ground water quality concerns in central Nebraska surfaced in the mid 1950s when scientists observed increasing N03-N concentrations in the ground water of some river valleys (Olson et aI., 1962). In Utah also, excessive N03-N contamination has been found in private wells. …

Microclimates And Tree Growth In Three Urban Spaces, Roger Kjelgren, James R. Clark

Plants, Soils, and Climate Faculty Publications

Microclimates characteristic of urban park, plaza, and canyon spaces were related to physiology and growth of even-aged sweetgum (Liquidambar styraciflua L.) street trees. Microclimates, tree growth, and physiological responses were characterized diurnally and seasonally. Park and plaza sites received unobstructed sunlight while the canyon was limited to four hours of direct solar radiation in midsummer. Potential seasonal insolation was 44 per cent of the potential maximum at the canyon and over 90 per cent at the park. Heating from paved surfaces at the plaza resulted in cumulative pan evaporation nearly 50 per cent greater than the other sites. Tree growth …

Photosynthesis And Leaf Morphology Of Liquidambar Styraciflua L. Under Variable Urban Radiant Energy Conditions, Roger Kjelgren, James R. Clark

Plants, Soils, and Climate Faculty Publications

Diminished sunlight, characteristic of urban canyons, has been suggested as being potentially limiting to plant growth. This study investigated the response of sweetgum (Liquidambar styraciflua L.) to variable irradiance in a range of urban locations. Diurnal photosynthesis was measured in situ on mature trees, comparing an open site at an urban park with an urban canyon that received 4 h of midday sun in midsummer. Photosynthesis for trees growing in the canyon was lower both during shaded and sunlit periods compared with trees at the park. Photosynthesis of detached shoots in a growth chamber was greater in canyon than park …

Ground-Water Policy-Making Support: Usem Optimization Modelling Plus Gis And Graphics, Richard C. Peralta, Christopher M. U. Neale, Ali Gharbi, Mazibur Khan, Oscar Daza, Douglas Ramsey, Kurt Vest

Civil and Environmental Engineering Faculty Publications

A support tool for ground-water management decision making involves integration of a multiobjective optimization model, GIS and graphics software. Two results are improved consideration of spatial data within the optimization model and improved conversion of optimal strategies to real-world application. Another result is improved visualization of the trade-offs involved between conflicting management goals.

Us/Wells Vs. 1.05 User's Manual, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Presented is a computer program, US/WELLS, that is designed to solve several types of groundwater management problems. The acronym US/WELLS stands for Utah State WELL System. This decision-support tool is usable by persons slightly familiar with groundwater hydraulics. It can be valuable for practical management of groundwater systems that satisfy certain criteria.

Ultrahigh Vacuum Chamber For Synchrotron X-Ray Diffraction From Films Adsorbed On Single-Crystal Surfaces, John R. Dennison, S. K. Wang, P. Dai, T. Angot, H. Taub, S. N. Ehrlich

All Physics Faculty Publications

An ultrahigh vacuum chamber has been developed for structural analysis of adsorbed films and single‐crystal surfaces using synchrotron x‐ray diffraction. It is particularly well suited for investigations of physisorbed and other weakly bound films. The chamber is small enough to transport and mount directly on a standard four‐axis diffractometer and can also be used independently of the x‐ray diffractometer. A low‐current, pulse‐counting, low‐energy electron diffraction/Auger spectroscopy system with a position‐sensitive detector enables in situ characterization of the film and substrate while the sample is located at the x‐ray scattering position. A closed‐cycle He refrigerator and electron bombardment heater provide controlled …

Electron Mean-Free Paths In The Alkali Metals, G. K. Wertheim, D. Mark Riffe, N. V. Smith, P. H. Citrin

All Physics Faculty Publications

Photoemission data in which the signal from the first atomic layer is well resolved from that of the bulk are used to determine accurately the kinetic-energy dependence of the inelastic-electron mean free path in the alkali metals. At the higher kinetic energies, the data are in very good agreement with the theory of Penn. Below about 10 eV, the mean free path in the heavier alkali metals drops markedly below the theoretical values. This is attributed to electron decay processes involving the unoccupied d bands.

Publishing Books, Ted Pease

Journalism and Communication Faculty Publications

WISE COMMENTATORS have long evaluated books and bookmaking. "Man builds no structure which outlives a book," wrote Eugene Fitch Ware in The Book, and Justin M'Carthy's A Ballade of Book-Making declared, "The critics challenge and defend ... of making books there is no end." Others have written loving odes to the book. Garrison Keillor, for instance: The book is a "great and ancient invention," he marveled, "slow to hatch, as durable as a turtle, light and shapely as befits a descendant of the tree .... A handsome, useful object begotten by the passion for truth ... [books] contain our common …

Convective Instability Of Autocatalytic Reaction Fronts In Vertical Cylinders, D. A. Vasquez, J. W. Wilder, Boyd F. Edwards

All Physics Faculty Publications

Linear stability analysis predicts that the onset of convection for an ascending autocatalytic reaction front in a vertical cylinder corresponds to a nonaxisymmetric mode. This mode consists of a single convective roll confined to the region near the reaction front, with fluid rising in half of the cylinder and falling in the other half. Experiments show a flat front below the onset of convection and an axisymmetric front well above the onset of convection. New experiments are called for to closely examine the onset of convection in order to test this prediction.

Final Environmental Impact Statement For Rangeland Ecosystem Management On He Uinta National Forest, Provo, Utah, Usda Forest Service

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

This Final Environmental Impact Statement describes alternatives, including a "No Action" alternative for management of National Forest Rangeland Resources on the Uinta National Forest. Alternatives range from no change from past management practices, which in some instances have resulted in less than favorable ecological conditions on National Forest Rangelands and riparian resources, to managing these resources to achieve the "Potential Natural Community" in terms of vegetative cover types and condition. The environmental consequences of all alternatives considered in detail are displayed. The alternatives selected for implementation will become an amendment to the Uinta National Forest Land and Resource Management Plan. …

Idaho River Systems Management Study Wetlands Report, United States Department Of The Interior, Bureau Of Reclamations

Natural Resources-Planning, Management, and Conservation

The Bureau of Reclamation is cooperating with the Idaho Department of Water Resources and others in the formulation of a comprehensive water plan for the conservation, development, management, and use of waters within the state's river basins. The impact that wetlands may have on the use of water in the state is a major consideration.

This report identifies opportunities that exist for private citizens, corporations, government agencies, and others to work together to slow the rate of wetland loss and to improve the quality of remaining wetlands. To work together effectively, these groups must reach an understanding of what comprises …

Sprinkler Irrigation-Pesticide Best Management Systems, A. Y. Ranjha, Richard C. Peralta, Robert W. Hill, A. M. Requena, Howard M. Deer, M. Ehteshami

Civil and Environmental Engineering Faculty Publications

The relative reduction in potential groundwater contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices, and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate irrigation application depths. The movement of pesticides through soils following sprinkler irrigations was simulated with a one-dimensional model. Pesticide contamination of groundwater can be reduced by careful selection of pesticides, using properly designed irrigation systems, and improved water management techniques. Procedures for selecting an appropriate sprinkler system design and pesticide are presented. KEYWORDS. Pesticides, Leaching, Sprinkler irrigation, Irrigation depth, Irrigation system design, Soil, …

Bulk And Surface Singularity Indices In The Alkali Metals, G. K. Wertheim, D. Mark Riffe, P. H. Citrin

All Physics Faculty Publications

Photoemission data from (110) films of Li, Na, and Rb, in which the signal from the first atomic layer is well resolved, show that the core-hole-screening singularity index is ∼40% larger at the surface than in the bulk for all three metals. This result, which is indicative of the more atomiclike character of metal surface atoms, in general, is particularly large for the alkali metals because their conduction-electron screening is mainly s-like. In addition to quantifying the difference in screening at the surface, the data provide bulk singularity indices of 0.22, 0.16, and 0.14 for Li, Na, and Rb, respectively. …

News 2000: Not My Kid! Journalists Leery Of Newspapers’ Future, Ted Pease

Journalism and Communication Faculty Publications

No abstract provided.

Thermal And Surface Core-Electron Binding-Energy Shifts In Metals, D. Mark Riffe, G. K. Wertheim, D. N. E. Buchanan, P. H. Citrin

All Physics Faculty Publications

High-resolution photoemission spectra from the shallow core levels of alkali metals and of In have been obtained between 78 K and room temperature. The data yield values for the alkali-metal surface-atom core-level shift and show thermal shifts of comparable size for bulk and surface. The positive surface shifts are due to the spill-out of conduction-electron charge, which is responsible for the surface dipole layer. The surface shifts are in good agreement with values obtained from a Born-Haber cycle expressed in terms of surface energies. The thermal shifts are proportional to the lattice expansion, and arise from both initial-state and final-state …

Calculation Of Barriers To Proton Transfer Using Variations Of Multiconfiguration Self‐Consistent‐Field Methods. Ii. Configuration Interaction, K. Luth, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Various means are tested of including additional electron correlation into multiconfiguration self‐consistent‐field (MCSCF) methods for computing proton transfer potentials in HF₂⁻, H₇N₂⁺, H₃O₂⁻, and H₅O₂⁺. Configuration interaction allowing single excitations (CIS) and configuration interaction with single + double excitations (CISD) calculations are performed following MCSCF expansion of the wave function using various different MCSCF reference wave functions. The CISD results are excellent, being fairly independent of choice of reference space although it is important that the occupied orbitals be balanced between the …

Coverage Dependence Of K Adsorption On Si(100)—2× 1 By Core-Level Photoemission, D. Mark Riffe, G. K. Wertheim, P. H. Citrin, J. E. Rowe

All Physics Faculty Publications

Using core-level photoemission, a coverage-dependent transition in the adsorption of K on Si(100)2×1 is observed. Below ∼0.25 monolayers, a single adsorption is occupied, the asymmetry of the Si-dimer reconstruction is enhanced, and no more than ∼0.05e is transferred from K to Si. Above this coverage, multiple sites are occupied, the dimer configuration becomes more symmetric, and the K overlayer becomes increasingly metallic. These findings resolve a number of conflicting studies of this system.

Finite Thermal Diffusivity At Onset Of Convection In Autocatalytic Systems: Continuous Fluid Density, J. W. Wilder, Boyd F. Edwards, D. A. Vasquez

All Physics Faculty Publications

The linear stability of exothermic autocatalytic reaction fronts is considered using the viscous thermohydrodynamic equations for a fluid with finite thermal diffusivity. For upward front propagation and a thin front, the vertical thermal gradient near the front is reminiscent of the Rayleigh-Bénard problem of a fluid layer heated from below. The problem is also similar to flame propagation, except that here the front propagation speed is limited by catalyst diffusion rather than by activation kinetics. For small density changes in a laterally unbounded system, the curvature dependence of the front propagation speed stabilizes perturbations with short wavelengths λ<λ_c, …

Western Forests And Air Pollution, United States Environmental Protection Agency

Pollution

This book addresses the relationships between air pollution in the western United States and trends in the growth and condition of Western coniferous forests. The West is defined in this case as the eleven conterminous states of California, Oregon, Washington, Idaho, Nevada, Arizona, New Mexico, Utah, Colorado, Wyoming, and Montana. Approximately one-third of the West is forested, primarily by coniferous forest types.

Cheese Industry Conference 1992, Various Authors

Cheese Industry Conference

No abstract provided.