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An Anatomical Investigation Of Roots From C3 And C4 Grasses With Emphasis On Phloem Organization, Eric A. Rechel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Root phloem structure was researched in taxonomically related C3 and C4 grass species. The functional aspect of phloem unloading in the root was then discussed in terms of this observed structure. In Triticum aestivum L. (C3) each phloem bundle consists of one protophloem sieve-tube element, two companion cells, and one metaphloem sieve-tube element. Protophloem sieve-tube elements and companion cells are contiguous with the pericycle. Centripetally the companion cells are in contact with the metaphloem sieve-tube element. All are separated from tracheary elements by stelar parenchyma. Eighty-four percent of the lateral connections observed in protophoem sieve-tube elements are associated with the …

The Influence Of Winter Social Behavior On The Habitat Selection And Reproductive Success Of The Black-Billed Magpie, Kerry P. Reese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the influence of winter social behavior, particularly dominance relationships, on the subsequent nesting habitat selection and reproductive success of Black-billed Magpies (Pica pica hudsonia) on 2 areas in northern Utah. Hierarchical cluster analysis ordinated the habitats available to breeding birds and Chi-square and Bonferoni-z statistics were used to determine those habitat types the magpies seemed to prefer. Social status was determined by observing color-banded birds engaged in agonistic encounters at winter bait stations. Social dominance was evaluated by % dyads won, not by total % victories. Relationships between winter social status of magpies and their …

Seed Case Studies On Atriplex Gardneri (Moq) Dietr.: Bracteole Cell Wall Composition And Enzymatic Degradation, Priscilla Woolley Burton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Clarification of the bracteole restraint on germination and the development of an improved seed pre-treatment were the objectives of this study. Bracteole cell walls were isolated and hydrolyzed with 72% sulfuric acid followed by dilution and further hydrolysis. Individual monosaccharide yields were monitored with gas chromaixtography and colorimetry. Lignin was determined as the acid insoluble residue . Cell wall composition on a dry weight basis was 17.0% lignin, 32 . 75% glucose, 28.77% xylose, 7.21% arabinose, 1.11% galactose and 0.35% mannose. Linear xylans and glucans represent a large portion of the cell wall . The quantity of lignified tissue is …

The Writing And Production Of A Series Of Mini-Documentary Radio Programs On Animal Control And Care In Logan, Camille Cornish-Dryden

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Human beings have for ages domesticated animals which they have kept for companionship as pets. Originally man and his animals lived on scattered farms and ranches where pets had plenty of room to roam. As human social structures changed and people crowded into towns and cities, the matter of controlling one's pets in order to prevent their becoming the neighbor's pests became a serious concern. Next to fights over water rights in the west, perhaps the most frequent cause for contention was the control of one's pets.

Evaluation Of The Utah Operational Weather Modification Program, Geoffrey E. Hill

Reports

This study is an evaluation of a winter orographic cloud seeding project in Utah. The evaluation is based upon both intensive field measurements and historic~l records. For the field measurements, ground and airborne data were collected during February and March, 1981 in the vicinity of the Tushar Mountains. In evaluating the physical data three aspects are emphasized: the dispersal of artificial ice nuclei, the distribution of supercooled liquid water, and the growth and trajectories of precipitation. Ground based measurements were made by K and X band radars, a dual frequency microwave radiometer, a network of precipitation gauges, an ice nucleus …

Utah Science Vol. 43 No. 1, Spring 1982

Utah Science

1 GRAZING FEES FOR PUBLIC LANDS: WHAT'S FAIR? D. B. Nielsen Formulas and fees help set the price of beef. They also are factors in rancher survival rates. Learn how the process works in this article.

7 BUR BUTTERCUP: A WEEDY IMMIGRANT M. E. Barkworth Whys and hows of plant transfers between regions and countries are solved by special detective work. A USU scientist wants to help in keeping track of Bur Buttercup migrations.

10 BUR BUTTERCUP: IT WILL GET YOUR SHEEP IF YOU DON'T WATCH OUT J. D. Olsen, T. E. Anderson, and G. Madsen Although not a true …

Analytical Scanning Electron Microscopy For Surface Science, Olive Lee-Deacon, Claude Le Gressus, Daniel Massignon

Scanning Electron Microscopy

To correlate an electron image with surface properties requires thorough understanding of electron-solid interaction, secondary electron emission mechanism and operation functions of image detectors. We emphasize the importance and usefulness of combining electron spectroscopy with scanning electron microscope in interpreting electron image contrast. Linear relationships among secondary electron image (SEI) brightness, total emission current and the integration of electron energy distribution were measured. We propose that channeling effect, instead of primary electron diffraction, is the crystallographic cause of SEI contrast. Secondary electrons contribute most to SEI brightness because of their high constituent in total yield, not because of high efficiency …

Proceedings From The 19th Annual Marschall Invitational Italian Cheese Seminar 1982, Various Authors

Cheese Industry Conference

No abstract provided.

Land Use Inventory Of Salt Lake County, Utah From Color Infrared Aerial Photography 1982, Kevin P. Price, Reynold D. Willie, Douglas J. Wheeler, Merrill K. Ridd

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

Salt lake County, Utah's major population center, continues to experience rapid urban growth. The Impacts of urbanization on land use patterns and natural resources in the county are of particular Interest to both state and local policy makers and planners. The effect of urban development on a dwindling agricultural land base and water resources must be assessed to allow a rational basis for future water allocation and land use planning .

A Transport Equation Theory Of Electron Scattering, D. J. Fathers, P. Rez

Scanning Electron Microscopy

The use of the Boltzmann transport equation to describe electron scattering in electron microscopy and electron probe microanalysis is discussed. A method of solution is given in which the transport equation is divided into angle and energy intervals. This gives rise to a number of coupled first order differential equations. Separation into forward and backward travelling components of the electron flux distribution enables the correct boundary conditions to be imposed. Solutions are derived which take the form of matrix operators analytic in both depth and target thickness. These matrices allow derivation of other physical quantities such as X-ray or Auger …

Monte Carlo Calculations On The Spatial And Angular Distributions Of High Energy Electron Beams In Amorphous And Polycrystalline Films, J. L. Balladore, J. P. Martinez, J. Trinquier, B. Jouffrey

Scanning Electron Microscopy

We study the plural scattering of electrons in amorphous and polycrystalline films. The incident electron energy ranges from 0.1 to 3 MeV. The cross sections are obtained by measuring the transmission coefficient for targets of gold, silver, aluminium and carbon. The partial elastic cross section is calculated from Lenz's theory using a Wentzel-Yukawa model for the atomic potential of the scattering atom. In the case of inelastic interactions, we take into account either scattering by a free atom (Morse's approximation) or scattering by plasmon creation (relativistic theory of Ashley Ritchie). From these results, we solve the problem of electron transport …

The Role Of The Background In Auger Electron Spectroscopy, H. E. Bishop

Scanning Electron Microscopy

In Auger Electron Spectroscopy (AES) the characteristic Auger peaks are superimposed on a relatively high continuum of back-scattered electrons. In the commonly used differential mode of recording Auger spectra, the influence of the background appears through its contribution to the noise and the enhancement of the Auger signal that makes a backscattering correction necessary in quantitative AES. With the increased use of low incident beam currents to achieve high spatial resolution, the direct spectrum is increasingly used, so that a better understanding of the background is desirable. In this paper the variations of the background with atomic number, incident beam …

Monte Carlo Simulation Of Electron Scattering In Resist Film/Substrate Targets, Kenji Murata

Scanning Electron Microscopy

First the fundamentals of resist modelling required to implement an analysis of developed resist patterns were studied, which represents the relationship between the energy deposited by incident electrons and the solubility characteristics of a positive or negative resist. Next, two models of single elastic scattering and fast secondary (knock-on) electron production were studied for Monte Carlo simulation of electron scattering in resist film/substrate targets, and the statistical errors of Monte Carlo results were evaluated. Finally, problems in electron beam lithography were investigated with the simulation. The exposure intensity distribution was studied with the two models. A comparison between Monte Carlo …

General Catalog 1982-1984, Utah State University

University Catalogs

General Catalog of 1982-1984

Contains course descriptions, University college calendar, and college administration.

Control Of Iron Chlorosis, Terry A. Tindall

Archived Gardening Publications

Publication discusses the causes of iron deficiency in plants and how to best control it.

Utah Geothermal Institutional Handbook, A User's Guide Of Agencies, Regulations, Permits And Aids For Geothermal Development, L. Ward Wagstaff, Stanley Green

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

The purpose of this handbook is to assist interested persons in understanding and complying with the various laws, regulations, and procedures associated with the development of geothermal resources in Utah. Included in the Handbook are lists of the main permits required and the names of agencies and persons associated with permits; a summary of pertinent laws, regulations, and permits; and charts outlining typical development and permitting procedures. The Handbook is intended as a general guide; the best and most reliable guidance for a prospective developer is through direct interaction with the respective regulatory agencies.

Use Of Multispectral Scanner Images For Assessment Of Hydrothermal Alteration In The Marysvale, Utah, Mining Area, United States Geological Survey

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

Multispectral images of an area near Marysvale, Utah, were collected by using the airborne U.S. National Aeronautics and Space Administration (NASA) 24-channel Bendix multispectral scanner; they were analyzed to define areas of hydrothermally altered, potentially mineralized rocks. Hydrothermally altered rocks, particularly volcanic rocks affected by solutions rich in sulfuric acid, are commonly characterized by concentrations of argillic minerals such as alunite and kaolinite. These minerals are important for identifying hydrothermally altered rocks in multispectral images because they have an intense absorption band centered near a wavelength of 2.2 um. Unaltered volcanic rocks commonly lack these minerals and hence do not …

In Situ And Laboratory Geotechnical Test Results From Borehole Gd-1 In Southeast Utah, United States Department Of Energy

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

In situ testing was conducted in the Gibson Dome No. 1 (GD-1) borehole in southeastern Utah at depths ranging from 954 to 1,507 m (3,130 to 4,945 feet). These tests were made in a number of salt strata to measure (1) stress-strain behavior of the borehole (hole "squeeze"); (2) short-term borehole creep; and (3) in situ stresses in salt strata. Laboratory triaxial strength and creep tests were conducted on core removed from GD-1 to provide engineering data under a variety of test conditions (stress state, strain rate, and temperature). Results of in situ and laboratory tests will be used to …

Lake Powell Water Quality Programs And Associated Files, A Users' Guide To Programs Powell And Powplot, United States Department Of The Interior, Bureau Of Reclamation

Water

During the summer of 1980, work began at the Engineering and Research Center, Bureau of Reclamation, to develop a computerized method for analyzing Lake Powell water quality data. Lake Powell, in southeastern Utah is formed by Glen Canyon Dam on the Colorado River at Page, Arizona. This work was carried out by Mr. Greg A. Keller under the supervision of Mr. David H. Merritt in the Colorado River Water Quality Office. By July of 1981, two computer programs, named POWELL and POWPLOT, had been produced. This document is intended to provide guidance for the user of these programs.

Ion Temperature Variations In The Daytime High-Latitude F Region, Robert W. Schunk, Jan Josef Sojka

All Physics Faculty Publications

We improved our high-latitude ionospheric model by including thermal conduction and diffusion-thermal heat flow terms in the ion energy equation so that we could study the ion temperature variations in the daytime high-latitude F layer in a region poleward of the auroral oval for steady state conditions at local noon. From our study we found that (1) The variation of Ti with solar cycle, season, and geomagnetic activity closely follows the Tn variation. The general trend is for higher temperatures in summer than in winter, at solar maximum than at solar minimum, and for active magnetic conditions than for quiet …

Modeling Of Depth Distribution Of X-Ray Production, J. D. Brown

Scanning Electron Microscopy

Knowledge of X-ray production as a function of depth by electrons (𝜙(𝜚z) curves) is important in quantitative electron probe microanalysis and other electron beam technologies. Extensive measurements of such curves have been made for electron energies between 6 and 30 keV and for many X-ray lines and matrix elements. Two experimental techniques based on measurements on sandwich or wedge shaped specimens have been used.

A number of expressions have been used to model 𝜙(𝜚z) curves from a square function through complicated polynomial expressions. Recently, a Gaussian model has been proposed which accurately reflects the shape of the 𝜙(𝜚z) curves and …

Some Applications Of The Electron Backscattering Diffusion Model, W. Czarczyński, Z. Radzimski

Scanning Electron Microscopy

Starting from a simple diffusion theory extended to oblique angles of incidence some empirical correction coefficients for electron backscattering have been found. These empirical coefficients have been used in calculations of backscattered electron surface density distribution, and good agreement with experimental data has been obtained.

Inelastic Scattering Of Electrons In Solids, C. J. Powell

Scanning Electron Microscopy

The principal mechanisms and available data for the inelastic scattering of electrons in solids are reviewed. The processes relevant for electron-probe microanalysis, electron energy-loss spectroscopy, Auger-electron spectroscopy, and x-ray photoelectron spectroscopy are described and examples of relevant electron energy-loss data are shown. The discussion is based on the dielectric description of inelastic scattering and treats processes important in the excitation of both core electrons and valence electrons. Information is given on the cross sections for excitations of valence electrons, cross sections for ionization of core levels, inelastic mean free paths of Auger electrons and photoelectrons in solids, and radiation damage.

Inelastic And Elastic Multiple Scattering Of Fast Electrons Described By The Transport Equation, Karl E. Hoffmann, Hans Schmoranzer

Scanning Electron Microscopy

A method for solving the transport equation for the propagation of electrons in the primary energy range of interest in electron beam technology has been developed which is based on discretizing the related integral equation. The integral equation is solved by a collocation procedure yielding a system of linear equations.

The elementary scattering processes were described for elastic scattering by quantum mechanical differential cross sections and for inelastic scattering by Gryzinski type semi-empirical excitation functions for core and outer electrons separately.

From the electron flux density calculated, angular and energy distributions of transmitted and backscattered electrons were derived for various …

An Investigation Of The Maximum Specimen Thickness For Differential Phase Contrast Lorentz Microscopy, R. P. Ferrier, G. R. Morrison, J. N. Chapman

Scanning Electron Microscopy

Examination of magnetic domain structure in the transmission electron microscope is generally confined to very thin foils, where the specimen approximates to a pure phase object, and is achieved by the long established methods of Fresnel or Foucault contrast Lorentz microscopy, or by differential phase contrast (DPC) imaging in a scanning transmission electron microscope (STEM).

If no quantitative interpretation of the image is required then magnetic contrast can be observed from thicker foils, and in this paper we describe an attempt to determine experimentally the range of foil thickness over which this is possible. To this end we have examined …

Electron Signal And Detector Strategy, L. Reimer

Scanning Electron Microscopy

The scintillator-photomultiplier combination (Everhart-Thornley detector) for detecting secondary and backscattered electrons (SE and BSE) has the best properties concerning signal-to-noise ratio and bandwidth as compared to other detectors (semiconductor detectors or channel plates).

Two opposite Everhart-Thornley detectors A and B are proposed for a better and reproducible angular selection of the SE. The field strength at the specimen is reduced either by a grid or ring electrode to separate the SE with regard to their exit momenta. This offers the possibility to record the signals A, B, A+B, and A-B. The signal A+B shows material and channelling contrast and the …

Monte Carlo Simulation Of Spatial Resolution Limits In Electron Beam Lithography, David F. Kyser

Scanning Electron Microscopy

Computer simulation of high energy primary electron scattering and subsequent generation of "fast" secondary electrons in thin film targets is demonstrated with Monte Carlo techniques. The hybrid model of Murata et al. (1981) is utilized to calculate the generation and subsequent spatial trajectory of each secondary electron in the target. The 3-dimensional spatial distribution of energy dissipation by such "fast" secondary electrons is shown to be the fundamental resolution limit for electron beam lithography with high-voltage beams (100 keV) and thin film polymer targets. The dependence of resolution on beam voltage and film thickness is presented, and quantitative comparison is …

Reduction Of Electron Beam Induced Radiation Damage Of Organic Material By Cooling To 4 K (Cryo Electron Microscopy), I. Dietrich, E. Knapek, G. Lefranc

Scanning Electron Microscopy

Structure investigations of organic, in particular biological, material are frequently performed with a strong electron beam. If the dose is higher than le/Ų, as required e.g. for high resolution electron microscopy, the results are strongly influenced by radiation damage. There are no means for preventing breaking of chemical bonds and ionizing of atoms and fractures of molecules due to the electron impact. The secondary processes, however, such as diffusion or evaporation of the fragments, can be strongly reduced by cooling the specimen to 4 K (cryoprotection). A suitable instrument for experimenting with cryoprotection is a microscope equipped with …

Detectors For Electron Energy Spectroscopy, David C. Joy

Scanning Electron Microscopy

The efficiency of the detector in an electron energy loss spectrometer is crucial to the performance of the system. The quality of this performance can be quantified in terms of the Detector Quantum Efficiency (DQE), the Modulation Transfer Function (MTF) and the radiation dose resistance (DR). The energy loss spectrum can be obtained either serially, by scanning the energy dispersion across a defining slit in front of a detector, or in parallel, by employing a detector or detectors with spatial resolution. The DQE, MTF and DR of serial detectors varies widely with the design chosen, but the fundamental limit to …

Electron Energy Loss Microspectroscopy And The Characterization Of Solids, Richard Leapman

Scanning Electron Microscopy

The inelastic scattering of fast electrons provides a detailed means of characterizing the chemical composition and electronic properties of thin samples in an electron microscope. Collective and single-electron excitations occuring in the low energy region of the spectrum can be described in terms of the generalized dielectric formulation. Important information is contained in this part of the spectrum but some prior detailed knowledge of the sample is usually required for proper interpretation. The core excitations allow microanalytical information to be obtained and quantitative procedures are now quite well developed at least for K and L edges. Sample thickness is one …