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Articles 288601 - 288630 of 303068

Full-Text Articles in Physical Sciences and Mathematics

1978-1979 Nova University Bulletin For The Academic Year, Nova Southeastern University Jan 1978

1978-1979 Nova University Bulletin For The Academic Year, Nova Southeastern University

Undergraduate Programs Course Catalogs

No abstract provided.


Emulsification And The Hlb-Temperature, Stig Friberg, Concepcion Solans Jan 1978

Emulsification And The Hlb-Temperature, Stig Friberg, Concepcion Solans

Chemistry Faculty Research & Creative Works

No abstract provided.


Relationship Between Stochastic And Differential Models Of Compartmental Systems, Jerome Eisenfeld Jan 1978

Relationship Between Stochastic And Differential Models Of Compartmental Systems, Jerome Eisenfeld

Mathematics Technical Papers

This paper shows that the differential equations model for compartmental systems is consistent with a stochastic description. Consequently, we may employ either a differential equations or a stochastic formulation for either parameter identification, or for physical interpretation, as best suits the purpose. The differential equations parameters, the so-called fractional transfer coefficients, may be determined from the corresponding set of stochastic parameters and vice versa.


Petrology Of The Bull-Of-The-Woods Intrusive Complex, James Streshley Jackson Jan 1978

Petrology Of The Bull-Of-The-Woods Intrusive Complex, James Streshley Jackson

Dissertations and Theses

An area of unmapped intrusions lies within the Bull-of-the-Woods Roadless Area of Mount Hood National Forest. A variety of andesites, dacites,and diorites intruding units of tuff and andesite lava flows crop out over.an area of 52 sq km. These intrusions do not appear on the Geologic Map of Oregon West of the 121st Meridian (Hells and Peck, 1961). The purpose of this investigation is to map and describe these intrusions, with attention to the following questions:

What is the petrographic and geochemical nature of these intrusions?

What is the order of emplacement of these intrusions?

What is the probable mechanism …


An Investigation Of Arsenic(V)-Catechol Complexes, Ronald P. Haak Jan 1978

An Investigation Of Arsenic(V)-Catechol Complexes, Ronald P. Haak

Dissertations and Theses

There is not, at this time, a simple method for the simultaneous determination of As (III) and As (V) at trace levels. The development of such as method is needed, as the toxicities of these two species differ so greatly.

As (III) and As (V) are polarographically reducible in the presence of excess catechol, but the wave produced by As (V) is depended on time, pH and catechol concentration as well as As (V) concentration. In order to understand this behavior, determination of formation constants for any complex species present were needed to identify which species is electroactive. The literature …


Purification And Characterization Of Nadh Oxidase And Peroxidase From Lactobacillus Casei, Louise Ann Barstad Jan 1978

Purification And Characterization Of Nadh Oxidase And Peroxidase From Lactobacillus Casei, Louise Ann Barstad

Dissertations and Theses

A protein exhibiting NADH oxidase and NADH peroxidase activity has been isolated from Lactobacillus casei in high purity. Evidence obtained through gel filtration, electrophoresis, and electrofocusing indicates that the two activities are characteristic of a single tetrameric protein with an approximate molecular weight of 240,000.


Plants As Pumps, E A N Greenwood Jan 1978

Plants As Pumps, E A N Greenwood

Journal of the Department of Agriculture, Western Australia, Series 4

Native species vary greatly in their ability to pump ground water.

CSIRO studies are measuring water use by different plants to plan revegetation strategies.


Fish Of Lake Mead And Lake Mohave, Robert C. Allan, Dennis L. Roden Jan 1978

Fish Of Lake Mead And Lake Mohave, Robert C. Allan, Dennis L. Roden

Publications (WR)

This publication offers an in-depth study of the fish and other organisms that live in Lakes Mead and Mohave. The history and background of the two lakes is offered, as well as information about diseases, parasites, and unusual fish occurrences. Food sources, predation and competition are also discussed.


Final Report Buffalo National River Ecosystems Part Iv, R. E. Babcock, E. E. Dale, R. L. Meyer, D. G. Parker, E. G. Smith, M. D. Springer Jan 1978

Final Report Buffalo National River Ecosystems Part Iv, R. E. Babcock, E. E. Dale, R. L. Meyer, D. G. Parker, E. G. Smith, M. D. Springer

Technical Reports

Sampling point locations and analytical procedures remained unchanged from those outlined in previous Buffalo National River Ecosystem reports. The only significant change in analytical procedures was a reversion to the glass fiber filter method for collection and extraction of samples for chlorophyll analysis. This change was neeessitated by a need for filtering a larger volume to obtain enough chlorophyll for an accurate measurement. Samples were collected monthly from April 9 through December 30. No samples were taken in January or February due to the extremely uncertain traveling conditions caused by the frequent snows. Prior research indicates that the December 30 …


Bird Utilization Of Woodland Habitat In The Eastern Quarter Of South Dakota, John M. Emmerich Jan 1978

Bird Utilization Of Woodland Habitat In The Eastern Quarter Of South Dakota, John M. Emmerich

Electronic Theses and Dissertations

Bird utilization of narrow, riparian woodland; riparian; block-like, tree claim; and linear, single-row windbreak habitats in the eastern quarter of South Dakota were studied during the spring migration, reproductive, and winter seasons. The relative importance of these three habitats and multi-row shelterbelt habitat was evaluated using bird species diversity (BSD), bird population density, and habitat preferences of individual bird species. Cluster analysis delineated distinctive vegetation cover types in each of the three habitats studied. Bird communities associated with each cover type were tabulated for comparison purposes and predication capabilities. Multiple regression analysis predicted physical and vegetation features of each habitat …


Diversity And Density Of Shelterbelt Bird Communities, Thomas E. Martin Jan 1978

Diversity And Density Of Shelterbelt Bird Communities, Thomas E. Martin

Electronic Theses and Dissertations

The number of bird species and the density of each species were monitored in 69 shelterbelts in eastern South Dakota during spring migration and breeding seasons in 1976 and 1977. A total of 44 different species of birds were found during breeding and 68 species during spring migration. Approximately 60 to 80% of the species in a shelterbelt eat insects as part of all of their diet. Most of these bird species are territorial. Usually only 1-2 pairs of a territorial species will reside in any one shelterbelt. This low density is caused by the limited habitat area that shelterbelts …


Molybdenum(V) Solutions In Hydrobromic Acid, Edwin Charles Perley Jan 1978

Molybdenum(V) Solutions In Hydrobromic Acid, Edwin Charles Perley

Electronic Theses and Dissertations

Interest in the coordination chemistry of molybdenum has increased greatly in recent years because of the discovery that molybdenum plays an active role in several redox enzymes. Model systems have been devised to gain insight into the function of molybdenum in these enzymes. Most model systems are believed to contain an oxomolybdate(V) dimer in equilibrium with a redox active monomer or dimer. A relatively simple system that shows important similarities to model systems is a molybdenum(V) solution in hydrobromic or hydrochloric acid. As in the model systems, these solutions are believed to contain monomers and dimers in equilibrium. The equilibria …


The Utah Ecology Project: Ecological Impact Of Weather Modification Studies In The Uinta Mountains, United States Deparment Of The Interior, Bureau Of Reclamation Jan 1978

The Utah Ecology Project: Ecological Impact Of Weather Modification Studies In The Uinta Mountains, United States Deparment Of The Interior, Bureau Of Reclamation

Elusive Documents

The Uinta Mountains are located in extreme northeastern Utah and

northwestern Colorado. The major portion of the range and all areas

rising above 3,050 m (10,000 ft) lie within five Utah counties (Daggett,

Duchesne, Summit, Uintah and Wasatch). The high elevation segment of

the range in Utah is commonly referred to as the High Uintas. This

report will consider only the so-called High Uintas.


Interstate 15 Through The Bear River Valley, U.S. Department Of Transportation Jan 1978

Interstate 15 Through The Bear River Valley, U.S. Department Of Transportation

Elusive Documents

No abstract provided.


Soil Losses From Utah Rangeland And Forestland, Lamar R. Mason Jan 1978

Soil Losses From Utah Rangeland And Forestland, Lamar R. Mason

Elusive Documents

No abstract provided.


Plasma Lines In The Auroral E Layer, Vincent B. Wickwar Jan 1978

Plasma Lines In The Auroral E Layer, Vincent B. Wickwar

All Physics Faculty Publications

The first successful measurements of plasma lines in the auroral E layer were made in January 1976 using the Chatanika incoherent scatter radar. Although they are considerably weaker than the signal from the ion component, the plasma line signals are readily detectable. Typical signal-to-noise ratios were about 4%. In this series of experiments, plasma lines were observed in the interval between 3.8 and 6.0 MHz, which corresponds to phase energies between 0.55 and 1.4 eV. They were found between 98 and 134 km; the derived plasma wave intensities varied between 0.06 and 1.0 eV, and the enhancements between 4 and …


Photoelectron Flux Build-Up In The Plasmasphere, G P. Mantas, Herbert C. Carlson, Vincent B. Wickwar Jan 1978

Photoelectron Flux Build-Up In The Plasmasphere, G P. Mantas, Herbert C. Carlson, Vincent B. Wickwar

All Physics Faculty Publications

Processes which confine photoelectrons to the plasmasphere (e.g., collisional backscattering from the thermosphere and magnetic trapping due to pitch angle redistribution through Coulomb collisions in the plasmasphere) tend to increase the steady state photoelectron flux in the plasmasphere above the amplitude level that would otherwise have been attained. Theoretical calculations are presented of steady state photoelectron fluxes in the plasmasphere, for specified atmospheric and ionospheric conditions. (Observational plasma line intensity data for these conditions exist and will be compared elsewhere.) General features of the angular distribution are presented and compared with observations. The transparency of the plasmasphere and the backscattering …


Time Lag In Diffusion-Controlled Nucleation, David Peak Jan 1978

Time Lag In Diffusion-Controlled Nucleation, David Peak

All Physics Faculty Publications

Nucleation occurring in the presence of a dense solvent is accompanied by spatial correlations among the reactant clusters and monomers which affect the aggregation rates. The classical theory of nucleation, which does not take such correlations into account, overestimates the observed nucleation rate and underestimates the time lag in condensed systems. An explicit expression for the time lag in diffusion‐controlled nucleation is derived. Values associated with miscibility gap experiments differ from the classical predictions by factors of 5 to 10.


On The Structure Of Divergence-Free Tensors, Ian M. Anderson Jan 1978

On The Structure Of Divergence-Free Tensors, Ian M. Anderson

Mathematics and Statistics Faculty Publications

Contravariant rank two tensors which are divergence‐free on one index and which are constructed from the metric tensor, an auxiliary collection of arbitrary tensor fields, and the first and second partial derivatives of these quantities are classified. The results generalize existing mathematical arguments in support of the Einstein field equations


Low-Cost Harvesting Systems For Intensive Utilization In Small-Stem Lodgepole Pine Stands, United States Department Of Agriculture, Forest Service Jan 1978

Low-Cost Harvesting Systems For Intensive Utilization In Small-Stem Lodgepole Pine Stands, United States Department Of Agriculture, Forest Service

Forestry

The study reported here had two objectives: (1) examine the feasibility of using inexpensive skidding equipment in a small-stem lodgepole pine stand in western Montana, and (2) determine forest residues volumes (unused wood) resulting from different ground skidding methods and utilization standards. Preharvest volumes, volumes removed, residues left on the ground, and unusable material hauled from the site were determined for various utilization standards. The efficiency of skidding with a horse, small tractor, and small rubber-tired skidder were compared.


Terpenes For Indirect Selection Of Growth Potential In Rocky Mountain Douglas-Fir, United States Department Of Agriculture, Forest Service Jan 1978

Terpenes For Indirect Selection Of Growth Potential In Rocky Mountain Douglas-Fir, United States Department Of Agriculture, Forest Service

Forestry

Possibilities of using terpene composition for indirect selection of growth potential were explored for Rocky Mountain Douglas-fir. Volatile leaf oil analyses were made on 170 5-year-old seedlings that represented full-sib hybrid families, wind-pollinated parental lines of inland origin, and wind-pollinated parental lines of coastal origin. Correlation analyses showed that terpenes could not be used efficiently for indirect selection of growth potential in the inland variety. But, terpenes may be useful in selecting parental lines in programs of intervarietal hybridization.


Linear Measurement: A Method Of Estimating Fascicle Numbers For Larch Casebearer Population Sampling, United States Department Of Agriculture, Forest Service Jan 1978

Linear Measurement: A Method Of Estimating Fascicle Numbers For Larch Casebearer Population Sampling, United States Department Of Agriculture, Forest Service

Forestry

Branch samples collected from 23 plots in northern Idaho and western Montana in 1975 had a combined mean distribution of 3.13 fascicles/inch (1.23 fascicles/cm) of branch length. By subsampling, it is possible to determine cumulative lineal inches of branch necessary to obtain a sampling unit of 100 fascicles for a plot, eliminating the need for counting fascicles on each sample.


Genetic Variation In Susceptibility Of Western White Pine To Needle Blight, United States Department Of Agriculture, Forest Service Jan 1978

Genetic Variation In Susceptibility Of Western White Pine To Needle Blight, United States Department Of Agriculture, Forest Service

Forestry

Ten clones of western white pine differed in their susceptibility to white pine needle blight. Two clones were significantly less infected than the average and two clones were significantly more infected than the average. This variability suggests a simple inheritance, maybe just one or two genes.


Timelag And Equililbrium Moisture Content Of Ponderosa Pine Needles, United States Department Of Agriculture, Forest Service Jan 1978

Timelag And Equililbrium Moisture Content Of Ponderosa Pine Needles, United States Department Of Agriculture, Forest Service

Forestry

The ponderosa pine (Pinus ponderosa Laws.) timber type covers nearly 9 million acres in the Rocky Mountains. The needle litter cast by these trees produces a highly flammable fuel when conditions are dry. The capability for fires to start and spread depends largely on the moisture content of surface fuels and their response to environmental changes. This report summarizes the results of laboratory tests to determine equilibrium moisture contents and absorption-desorption timelags below fiber saturation of ponderosa pine needles. Conducting the tests at conditions below fiber saturation eliminated consideration of the movement of free water and possible leaching of the …


Effect Of Growing Season On Sprouting Of Blue Huckleberry, United States Department Of Agriculture, Forest Service Jan 1978

Effect Of Growing Season On Sprouting Of Blue Huckleberry, United States Department Of Agriculture, Forest Service

Forestry

Vaccinium globulare, blue huckleberry, was clipped on five dates from May 19 to August 4. All clipping treatments caused more lateral bud release than occurred in control plants. May, June, and early July treatments caused the same amount of dormant bud release. The amount of shoot growth from released buds corresponded to the amount of growing season remaining after treatment. Irregularity between plants in shoot development after the July 8 treatment and the lack of bud development after the August 4 treatment are attributed to the onset of seasonal bud dormancy.


Effects Of Burning Moist Fuels On Seedbed Preparation In Cutover Western Larch Forests, United States Department Of Agriculture, Forest Service Jan 1978

Effects Of Burning Moist Fuels On Seedbed Preparation In Cutover Western Larch Forests, United States Department Of Agriculture, Forest Service

Forestry

Natural seeding is normally the preferred method of regenerating conifers in the Northern Rocky Mountains (Schmidt and Shearer 1973). Some seedbed preparation is usually necessary for successful natural regeneration. Shade intolerant species such as western larch (Larix occidentalis Nutt.) regenerate best on bare mineral soil.


Predicting Slash Depth For Fire Modeling, United States Department Of Agriculture, Forest Service Jan 1978

Predicting Slash Depth For Fire Modeling, United States Department Of Agriculture, Forest Service

Forestry

Slash or debris created by harvesting and thinning are a major fire management problem because these residues can create unacceptable fire behavior hazards. Treating slash to maintain an acceptable fire hazard is expensive and requires skillful decisionmaking. An inexpensive, simple-to-use, yet objective means of appraising the potential fire behavior of slash is added to aid decisions in managing slash. Knowledge of potential fire behavior can help determine treatment alternatives, the financing of slash treatment activities, and even determine whether the slash should be created. This report describes a method for predicting depth of slash fuels for analytical modeling of fire …


Variation In Suckering Capacity Among And Within Lateral Roots Of An Aspen Clone, United States Department Of Agriculture, Forest Service Jan 1978

Variation In Suckering Capacity Among And Within Lateral Roots Of An Aspen Clone, United States Department Of Agriculture, Forest Service

Forestry

Excised roots were used to determine variation in suckering capacity among and within lateral roots of an aspen (Populus tremuloides Michx.) clone. Differences among lateral roots were significant. Within segments of a lateral root sucker production showed a high degree of polarity, increasing from the distal to proximal ends. There was no evidence of a gradient in suckering capacity in a segmented root; i.e., distal segments were not significantly different from proximal ones. This indicated that aging was not a factor regulating suckering within lateral roots. Sucker production was not affected by root length.


A Hydrologic Model Of Aspen-Conifer Succession In The Western United States, United States Department Of Agriculture, Forest Service Jan 1978

A Hydrologic Model Of Aspen-Conifer Succession In The Western United States, United States Department Of Agriculture, Forest Service

Forestry

Hydrologic impacts of grass-forb to aspen to conifer succession in the Rocky Mountain area are simulated by means of a fundamental model. Model algorithms representing hydrologic processes are sensitive to vegetational changes within the subalpine vegetation zone. Reductions in water yield are predicted as the vegetation on a small Utah watershed proceeds from a grass-forb type to aspen to conifers. Streamflow changes are largely attributable to an interaction between seasonal consumption for each vegetation type and the influence of vegetation type on snowpack. The model synthesizes present understanding and provides a framework for future watershed research.


Converting Forest Residue To Structural Flakeboard - The Fingerling Concept, United States Department Of Agriculture, Forest Service Jan 1978

Converting Forest Residue To Structural Flakeboard - The Fingerling Concept, United States Department Of Agriculture, Forest Service

Forestry

Structural-grade flakeboard experimentally manufactured from forest residues showed mean strengths above 5,500 psi and stiffness (MOE) above 600,000 psi. For economical transport, residues are chipped into "fingerlings" in the woods. Chipping rates are estimated at 50 tons per hour for large residues, and 15 tons per hour for small residues -- using different machines. Depending on the harvesting system selected, estimated costs of fingerlings delivered to the mill range from $25 to $33 per bone-dry ton for systems other than cable yarders.