Digital Commons Network^™

Segregation Of Copper To The Surface Of Copper-Nickel Alloys, Peter A. Dowben

Peter Dowben Publications

Copper segregation profiles at the surfaces of Cu₁₇Ni₈₃(111) and Cu₁₇Ni₈₃(100) have been calculated by a semiempirical procedure based upon previously published data. These profiles indicate that surface enrichment of copper is not limited only to the topmost layer but occurs for several layers away from the surface as well. A comparison of the calculated segregation profiles based upon the experimental results for the (100) and (111) surfaces of Cu₁₇Ni₈₃ do not agree with predictions based upon thermodynamic models of segregation.

Blas, Linear, Algebra Modules And Supercomputers Parvec Workshop #4, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

(Super)Conformal Symmetry Breaking, Andrew Strominger, V. Parameswaran Nair

Publications and Research

We argue that the only consistent way to break conformal invariance in a quantum theory of gravity is spontaneously in a finite locally conformal supersymmetric theory. This generically occurs whenever scalar fields are present. Covariant surface-integral expressions for the super-charge and four-momentum in terms of asymptotically constant spinor fields are derived. These are used to discuss stability and other aspects of the theory.

Lattice Dynamics Of Mixed Crystals Of Tise2, Roger D. Kirby, G.A. Freund, Jr.

Roger Kirby Publications

We present the results of Raman scattering measurements on the mixed-crystal systems TiSe_2-xS_x, TiSe_2-xTe_x, Zr_xTi_1-x Se₂. At room temperature with the pure compounds all have crystal structures represented by the D_3d(P3̃m1) space group with three atoms per unit cell. There are two Raman-active k=0 phonons, one of A_1gˉ symmetry and one of E_g symmetry. In the TiSe_2-xTe_x system, the A_1gˉ and E_gˉ phonon frequencies shift smoothly with concentration, and the shifts are well described by a simple virtual-crystal …

A Model For Orientation Effects In Electron‐Transfer Reactions, Paul Siders, Robert J. Cave, R.A. Marcus

All HMC Faculty Publications and Research

A method for solving the single‐particle Schrödinger equation with an oblate spheroidal potential of finite depth is presented. The wave functions are then used to calculate the matrix element T_BA which appears in theories of nonadiabatic electron transfer. The results illustrate the effects of mutual orientation and separation of the two centers on T_BA. Trends in these results are discussed in terms of geometrical and nodal structure effects. Analytical expressions related to T_BA for states of spherical wells are presented and used to analyze the nodal structure effects for T_BA for the spheroidal wells.

An Analysis Of The Effect Of Network Load And Topology On The Performance Of Concurrency Control Algorithm In Distributed Database Systems, Anoop Singhal, Amit P. Sheth, Ming T. Liu

Kno.e.sis Publications

Earlier studies in the performance analysis of concurrency control algorithms in distributed database systems (DDBS) have assumed that the message transmission time between any two nodes of a network is constant. Hence they disregard the effect of communication subnet related parameters such as network traffic, network topology, the capacity of transmission channels and the size of messages transmitted. In this paper an analytical model is used to estimate the delays in transmission channels for a DDBS in a long haul network. The analysis shows that the constant transmission time assumption cannot be justified in many cases and that response time …

The Variability Of Holocene Climate Change: Evidence From Varved Lake Sediments, Walter E. Dean, J. Platt Bradbury, Roger Y. Anderson, Cathy Barnosky

United States Geological Survey: Staff Publications

Varved sediments from a lake near the present forest-prairie border in northwestern Minnesota provide an annual record of climate change for the last 10,400 years. Climate-sensitive mineral, chemical, and biological components show that the mid-Holocene dry interval between 8500 and 4000 years ago is asymmetrical and actually consists of two distinct drier pulses separated by a moister interval that lasted about 600 years. Cyclic fluctuations with periods of several hundred years were abrupt and persistent throughout the Holocene and are most clearly recorded within the two drier pulses.

Livestock Guarding Dogs Protect Domestic Sheep From Coyote Predation In Kansas, William F. Andelt

Great Plains Wildlife Damage Control Workshop Proceedings

Sheep (Ovis cries/ producers were surveyed in Kansas to determine the efficacy of livestock guarding dogs (Canis familiaris) for protecting sheep from coyote (Canis latrans) predation. The majority of producers rated their guard dogs' predator control performance as good or excellent, indicating. that the dogs reduced their reliance on other control methods and substantially reduced monetary losses.

Survey Of Routing Algorithms For Computer Networks, Lu Yu, Thomas J. Sager

Computer Science Technical Reports

This thesis gives a general discussion of routing for computer networks, followed by an overview of a number of typical routing algorithms used or reported in the past few years. Attention is mainly focused on distributed adaptive routing algorithms for packet switching (or message switching) networks. Algorithms for major commercial networks (or network architectures) are reviewed as well, for the convenience of comparison.

Second S.R. Romania-U.S.A. Seminar On Polymer Science, Otto Vogl, Viorica Dobrescu

Emeritus Faculty Author Gallery

No abstract provided.

Polymer Science And Technology In Universities In Sweden, Otto Vogl, Bengt Ranby

Emeritus Faculty Author Gallery

No abstract provided.

A Study Of The Crayfish Orconectes Immunis In An Intermittent Nebraska Stream, John J. Shadle

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

House Mouse Populations And Their Damage To Common Building Insulations, Daryl D. Fisher

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

Small Mammal Populations And Rodent Damage In Nebraska No-Tillage Crop Fields, Kent E. Holm

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

The Prairie Naturalist Volume 16, No. 4. December 1984

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

TABLE OF CONTENTS

VEGETATION PATTERNS IN RELATION TO TOPOGRAPHY AND EDAPHIC VARIATIONS IN NEBRASKA SAND HILLS PRAIRIE ▪ P. W. Barnes, A. T. Harrison and S. P. Heinisch

GREAT BLUE HERON NESTING BIOLOGY ON THE JAMES RIVER IN SOUTH DAKOTA ▪ E. M. Dowd and L. D. Flake

OVENBIRDS AT THE PERIPHERY OF THEIR RANGE IN WESTERN NORTH DAKOTA ▪ R. B. Hopkins

BREEDING BIRD COMMUNITY COLONIZATION OF SOWN STANDS OF NATIVE GRASSES IN NORTH DAKOTA ▪ K. F. Higgins, T. W. Arnold and R. …

Using Urea Nitrogen As A Fertilizer, Kenneth L. Wells

Soil Science News and Views

Solid granular or prilled urea (45-46% N) has become widely available in Kentucky, as has 28% nitrogen solution (UAN solution) which is half urea and half ammonium nitrate. When applied to a field, urea is transformed to ammonium N soon after application. The rate of transformation is greatly increased by urease, the enzyme found to varying degrees in soil and on plants and plant residues. Due to the chemical reactions involved as urea nitrogen undergoes transformation, there is some degree of likelihood for volatilization loss of some N. Whether such a loss will occur, and how much N will be …

Assessment Of Landsat For Rangeland Mapping, Rush Valley, Utah, United States, National Aeronautics And Space Administration

Range Management

The objective of this investigation is to assess the feasibility of using Landsat MSS (multispectral scanner) data to identify and map cover types for rangeland, and to determine comparative condition of the ecotypes. A supporting objective is to assess the utility of various forms of aerial photography in the process.

If rangeland can be efficiently mapped with Landsat data, as supported by appropriate aerial photography and field data, then uniform standards of cover classification and condition may be applied across the rangelands of the state. Further, a foundation may be established for long-term monitoring of range trend, using the same …

The Probe, Issue 48 - December 1984

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association No. 48 December, 1984
Why do We have Laws Requiring the Preservation of Species?
Animal Rightists
Tennessee Coyotes
Letters to Ye Ed
Northwest Section WIldlife Meeting 1984
Live Trap
Psycho Coyote
Mobilization of Animals
National Park Systems do Differ
Blackfooted Ferrets
Animal Liberation
Raccoon Problems
Animal Protection Institute

Benthic Diatom Community Dynamics In The Colorado River: Interactive Effects Of Periodic Dessication And Current Regime, Christopher Gerard Peterson

Publications (WR)

The response to periodic desiccation of periphyton communities developed in eddy environments or in areas exposed to variable, direct current was examined. Algal communities were incubated on clay tiles for between 2 and 12 weeks in the Colorado River, directly below Hoover Dam from October, 1983 - January, 1984. Mean daily discharge from the dam decreased over this period. To assess the influence of these discharge changes on community dynamics, samples collected over the first 12 weeks of the investigation were compared to samples of the same age collected over the final 8 weeks.

The small diatom taxon Achnahthes spp …

On Finite Element Methods For The Euler-Poisson-Darboux Equation, Anatoly M. Genis

Mathematics and System Engineering Faculty Publications

We deal primarily with the derivation of various convergence estimates for some semidiscrete and fully discrete procedures which might be used in the approximation of exact solutions of initial-boundary value problems with homogeneous Dirichlet boundary conditions for the Euler-Poisson-Darboux equation. Although the equation is of hyperbolic type, the results are somewhat analogous to those known for parabolic equations, due to the presence of a limited 'smoothing' property. This paper contain L//2 estimates, maximum norm estimates, negative norm estimates, interior estimates of difference quotients and superconvergence estimates of the error.

Observations Of Shadow Bands At The Total Solar Eclipse Of 16 February 1980, Laurence A. Marschall, Rita Mahon, Richard C. Henry

Physics and Astronomy Faculty Publications

Photoelectric observations of short term light variations (shadow bands) at the 16 Feb. 1980 total solar eclipse have been made using a set of spatially separated PIN diodes. Light variations in a bandpass of 1-500 Hz were detected during the half-minutes preceding and following the total phase. Fourier analysis of the noise spectrum of the variations reveals a sharp drop-off for frequencies about 50 Hz and an overall spectrum quite similar to previously reported power spectra of stellar scintillation. This is consistent with an atmospheric origin for the shadow bands. Cross-correlations between the detector outputs are low, suggesting a short …

Increased Optical Damage Resistance In Lithium Niobate, D. A. Bryan, Robert Gerson, H. E. Tomaschke

Physics Faculty Research & Creative Works

We have confirmed greatly improved resistance to photorefractive damage in compositions of lithium niobate containing 4.5 at. % MgO or more. Holographic diffraction measurements of photorefraction demonstrated that the improved performance is due to a hundredfold increase in the photoconductivity, rather than a decrease in the Glass current. The diffraction efficiency shows an Arrhenius dependence on temperature, with an activation energy of 0.1 eV for the damage-resistant compositions, compared with 0.5 eV for undoped or low-magnesium compositions. The damage-resistant compositions are distinguished by a 2.83-μm absorption line instead of the usual 2.87-μm line due to the OH-stretch vibration.

High Recovery Desalting Of Brackish Water By Electrodialysis: Field Tests At Yuma Desalting Test Facility & At La Verkin Springs, United States Department Of The Interior, Bureau Of Reclamation

Water

An ED (electrodialysis pilot plant achieved high desalting recoveries of nearly 95 percent at the YDTF (Yuma Desalting Test Facility, Arizona) and 92 percent at LVS (La Verkin Springs, Utah) during over 4000 hours of operation. Brine TDS (total dissolved solids) concentrations of nearly 100 000 g/m³ were obtained at LVS, which is a greater brine concentration than is possible using RO (reverse osmosis). The LVS required ED energy (while producing a product TDS concentration of about 1000 g/m³) is estimated to be about one-third the energy requirements of a commercially available distillation brine concentrator. Lowering product …

Geology Of Ponca State Park, Nebraska, Roger K. Pabian, Dennis R. Lawton

Conservation and Survey Division

No abstract provided.

An Integrated Gis/Remote Sensing Data Base In North Cache Soil Conservation District, Utah: A Pilot Project For The Utah Department Of Agricultures Rims (Resource Inventory And Monitoring System), Douglas J. Wheeler, Merrill K. Ridd, John A. Merola

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

The RIMS program is designed "To provide SCD (Soil Conservation District) supervisory with adequate data about agriculture and related natural resources of their district and to use this data for district responsibilities" (Utah Department of Agriculture 1984). The department's guidelines for RIMS go on to describe SCD responsibilities for short and long-term conservation inputs into various state resource plans, giving direction to Agriculture Resource Development Loan fund programs, and giving direction to SCD programs. The guidelines emphasize the established institutional role of the SCD as a local body to deal with local resource issues in the context of a regional …

Yellow Giants In Young Clusters. Ii. A Comparison Of Observation With Theory, Edward G. Schmidt

Edward Schmidt Publications

Luminosities and effective temperatures are calculated for 17 nonvariable yellow giants and supergiants and nine Cepheids which were previously identified as members of open clusters. These stars are identified as being in the helium core burning stage of evolution. A comparison with the predictions of pulsation theory does not show any disagreement. On the other hand, several comparisons with the theory of stellar evolution produce discrepancies which suggest that effects neglected in the calculations may play an important role in the evolution of these stars.

Threshold Effect In Mg-Doped Lithium Niobate, K. L. Sweeney, L. E. Halliburton, D. A. Bryan, R. R. Rice, Robert Gerson, H. E. Tomaschke

Physics Faculty Research & Creative Works

Optical absorption spectra were obtained after reducing (i.e., vacuum annealing) a series of LiNbO3 crystals grown from melts having various Mg concentrations and Li/Nb ratios. A band peaking at 500 nm, and assigned to oxygen vacancies containing two electrons, was the only absorption present in one set of crystals following reduction. In contrast, two overlapping bands peaking near 1200 and 760 nm were present in the other set of crystals immediately after the reduction. The 1200-nm band is assigned to a previously unreported electron trap and the 760-nm band to oxygen vacancies containing only one electron. These data are interpreted …

Microprocessor-Based Pressure Controller, E. Redd, John T. Park

Physics Faculty Research & Creative Works

A device for automatic control of pressure in an ion-atom scattering experiment has been constructed. The system was modeled to achieve the minimum time for transition from one pressure to another. The pressure controller "learns" the system response and iterates the parameters used in "profiling" the valve voltage to reduce the transition time. The device has been used with two different scattering chambers and has worked well with both.

Optimal Placement For Multi-Terminal Nets, Mikhail J. Atallah, Susanne E. Hambrusch

Department of Computer Science Technical Reports

No abstract provided.

The Tilde Project, Douglas E. Comer, John T. Korb, Thomas Murtagh, Walter Tichy

Department of Computer Science Technical Reports

No abstract provided.