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Cation Exchange And Transport In Soil Columns Undergoing Miscible Displacement, Sung-Ho Lai May 1970

Cation Exchange And Transport In Soil Columns Undergoing Miscible Displacement, Sung-Ho Lai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mathematical model was developed to predict the exchange of one cation by another in a soil column undergoing one dimensional cation solution displacement under steady state flow conditions. The model allowed prediction of both the solution and exchanger phase concentration of the cation in question.

The model consists of a material balance equation which is a parabolic type partial differential equation. The assumption was made that equilibrium was reached instantaneously between the cations in the solution phase and the exchanger phase. This assumption reduced the material balance equation to a form that allowed numerical solution providing the data concerning …


The Photochemical Reduction Of Octacyanomolybdate(V) Ion In Aqueous Solutions, Gordon W. Gray May 1970

The Photochemical Reduction Of Octacyanomolybdate(V) Ion In Aqueous Solutions, Gordon W. Gray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The photochemical reactions occurring in aqueous solutions of octacyanomolybdate(V) ion, Mo(CN)83-, during irradiation with light of 365 and 436 nm wavelengths were studied. The quantum yields and reaction products were determined for neutral, unbuffered solutions as well as solutions buffered at pH 4.0, 7.0, and 9.0.

The results of these studies showed that the Mo(CN)83- ion is rapidly reduced by light to a Mo(IV) complex. In neutral or acidic media, the initial photoreduction product was found to be the red heptacyanoaquomolybdate(IV) ion, Mo(CN)7(H2O)3-. Photolysis in basic solution gave the …


A Comparative Roentgenographic Cephalometric Study Of The Facial Profile Of Orthodontic Patients Treated At Loma Linda University With Winners Of The "Smiles Of The Year" Contest, Romeo I. Stoll May 1970

A Comparative Roentgenographic Cephalometric Study Of The Facial Profile Of Orthodontic Patients Treated At Loma Linda University With Winners Of The "Smiles Of The Year" Contest, Romeo I. Stoll

Loma Linda University Electronic Theses, Dissertations & Projects

The "Smiles of the Year" winners and patients treated at Loma Linda University by the extraction or non-extraction approach were compared by linear and angular variables of skeletal, dental and soft tissue components. These findings were analyzed statistically to determine significant differences in the profile and detect the relationship between the integument and hard structures.

The following conclusions were drawn from this investigation to reflect the trend of treatment at Loma Linda University.

  1. After treatment the patients had less skeletal convexity, but were more convexity than established standards.
  2. The incisors of the patients treated by the extraction approach were less …


82nd Session Of The Iowa Academy Of Science, April 24-25, 1970, Iowa Academy Of Science Apr 1970

82nd Session Of The Iowa Academy Of Science, April 24-25, 1970, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Strategic And Related Considerations In The Development Of A Northwest Passage, Norman E. Larsen Apr 1970

Strategic And Related Considerations In The Development Of A Northwest Passage, Norman E. Larsen

Marine Affairs Theses and Major Papers

Environmental factors which have impeded activity in the Arctic, in the past, remain significant barriers to the development of the Northwest Passage. Consequently, enormous capital as well as bilateral planning and cooperation between United States and Canadian public and private agencies will be required if significant progress is to be achieved. The resource wealth of the Arctic promises the economic incentives essential to the eventual development of a transportation system to permit exploitation of these resources. Development of a commercially feasible Northwest Passage is both economically and strategically desirable. However, immense physical and engineering problems remain to be solved.


Keynote Address --- "The Year Of Ecology", Robert I. Cushing Mar 1970

Keynote Address --- "The Year Of Ecology", Robert I. Cushing

Vertebrate Pest Conference Proceedings: 4th (1970)

It seems to me that there are at least two things we should be concerned about. First, I believe there is a real possibility that the environmental quality bandwagon will get to playing so loud and to rolling so fast that there can be some unfavorable consequences in food production and processing-—the job I work at and that some of you work at. Second, I believe there are signs that we could lose our balance—-that we could be making decisions on emotional instead of rational grounds. Reason seems to be in danger from an epidemic of emotion. And we need …


The Organisation Of Rabbit Control (Oryctolagus Cuniculus) In Western Australia, A. R. Tomlinson, C. D. Gooding Mar 1970

The Organisation Of Rabbit Control (Oryctolagus Cuniculus) In Western Australia, A. R. Tomlinson, C. D. Gooding

Vertebrate Pest Conference Proceedings: 4th (1970)

ABSTRACT: Under Western Australian legislation, landholders have an obligation to control rabbits on their properties; local authorities the responsibility to supervise their work whilst the Agriculture Protection Board has a Statewide supervisory and co-ordination role. Prior to 1950 (when the Agriculture Protection Board was formed) the central role was in the hands of a Government department which, through lack of staff and money was unable to provide adequate supervision, and rabbits were in plague proportions. Since 1950, the Board has actively engaged in a vigorous policy aimed at tighter control and supervision. To enable this, the Board has entered into …


Algal Growth And Decomposition: Effects On Water Quality, Edward G. Foree, John S. Tapp Jr. Mar 1970

Algal Growth And Decomposition: Effects On Water Quality, Edward G. Foree, John S. Tapp Jr.

KWRRI Research Reports

The chemical composition of algae grown in batch culture depends mainly on environmental conditions, nutrient availability, presence of predators, cell age, and species. The effects of nutrient availability and cell age on the composition of three unialgal cultures (algae + bacteria) and one hetergeneous culture (algae + bacteria + microscopic animals) were evaluated. The cultures were grown in batch culture under both nutrient-abundant and nutrient deficient conditions and the changes in compositions were observed. Luxurious uptake where nutrients are incorporated into cellular protoplasm at levels greater than those necessary for growth, and super-luxurious uptake, where some nutrients are stored rather …


Rbe, Let, And Z/ΒΑ, Robert Katz Jan 1970

Rbe, Let, And Z/ΒΑ, Robert Katz

Robert Katz Publications

A call has been issued by Turner and Hollister in this journal for nomination of a suitable combination of charge and velocity to replace LET. It is the purpose of this communication to point out that no single combination of these variables can fully characterize track effects, as these are affected by the ratio of the range rm of the delta ray of maximum energy to the radius a0 of the sensitive volume.


Microbiological Specialists' Meeting New Mexico State University, Las Cruces, New Mexico April 3-4, 1970, U.S. International Biological Program Jan 1970

Microbiological Specialists' Meeting New Mexico State University, Las Cruces, New Mexico April 3-4, 1970, U.S. International Biological Program

Meetings

No abstract provided.


Distribution Of Trace Elements In Impoundments, J. Nix Jan 1970

Distribution Of Trace Elements In Impoundments, J. Nix

Arkansas Water Resources Center Technical Reports

An investigation of the trace element content of two impoundments on the Ouachita River, Arkansas, was conducted. Common water quality parameters were followed in the reservoirs in an effort to determine the factors which were influencing the trace element concentration. The following trace metals were determined in both the particulate phase (retained by a 0.45 micron filter) and the soluble phase (passed by a 0.45 micron filter): iron, manganese, copper, cobalt, nickel, lead, chromium, and zinc. These measurements were made periodically for one and a half years. Results indicate that the chemical regime of the impoundments which were studied was …


Supplying Wood Products For More People - A Challenge To The Forest Industry, John A. Segur, F. Bruce Lamb, Basil E. Allen Jan 1970

Supplying Wood Products For More People - A Challenge To The Forest Industry, John A. Segur, F. Bruce Lamb, Basil E. Allen

Yale School of the Environment Bulletin Series

No abstract provided.


Part I - Controlling The Soil Moisture Environment Of Transpiring Plants, Part Ii - Prediction Of Leaf Temperature Under Natural Atmospheric Conditions, Charles T. Haan, Billy J. Barfield, Robert Edling Jan 1970

Part I - Controlling The Soil Moisture Environment Of Transpiring Plants, Part Ii - Prediction Of Leaf Temperature Under Natural Atmospheric Conditions, Charles T. Haan, Billy J. Barfield, Robert Edling

KWRRI Research Reports

Part I

A technique for controlling the soil moisture potential in the root zone of transpiring plants was developed. The method uses the principles of unsaturated flow through a porous media to develop the desired moisture potential. In the case of non-steady state transpiration, the maximum possible fluctuation in the soil moisture potential can be determined by the techniques presented.

Part II

Two implicit leaf temperature prediction equations were derived from the energy balance approach. The equations define sensible and latent heat transfer from a plant population as a two step process:

  1. Transfer between the plant leaf and the canopy …


Anticipations Of Change: A Socio-Economic Description Of A Kentucky County Before Reservoir Construction, Charles Robert Smith Jan 1970

Anticipations Of Change: A Socio-Economic Description Of A Kentucky County Before Reservoir Construction, Charles Robert Smith

KWRRI Research Reports

In the past the construction of large reservoirs in the United States has been evaluated largely in terms of the economic benefit they bring to the area where they are constructed and to the nation. Where human populations are involved, however, a host of social changes occur, many of which fundamentally alter the way of life of a people.

This report is part of a larger study which aims at analyzing the social costs and benefits of reservoir construction. The project is long range in that studies are to be carried out before, during, and after construction. This report concentrates …


Opset Program For Computerized Selection Of Watershed Parameter Values For The Stanford Watershed Model, Earnest Yuan-Shang Liou, L. Douglas James Jan 1970

Opset Program For Computerized Selection Of Watershed Parameter Values For The Stanford Watershed Model, Earnest Yuan-Shang Liou, L. Douglas James

KWRRI Research Reports

The advent of high-speed electronic computer made it possible to model complex hydrologic processes by mathematical expressions and thereby simulate streamflows from climatological data. The most widely used program is the Stanford Watershed Model, a digital parametric model of the land phase of the hydrologic cycle based on moisture accounting processes. It can be used to simulate annual or longer flow sequences at hourly time intervals. Due to its capability of simulating historical streamflows from recorded climatological data, it has a great potential in the planning and design of water resources systems. However, widespread use of the Stanford Watershed Model …


The Ultraviolet Absorption Spectra Of Solutions Of 2, 4, 6-Trimethoxybenzoic Acid In Sulfuric Acid, Kathy Show-Shing Ho Jan 1970

The Ultraviolet Absorption Spectra Of Solutions Of 2, 4, 6-Trimethoxybenzoic Acid In Sulfuric Acid, Kathy Show-Shing Ho

Masters Theses

"Studies of the ultraviolet and proton magnetic resonance spectra of solutions of 2,4,6-tribromo-, trichloro-, trimethyl- and trinitro-benzoic acids dissolved in concentrated sulfuric acid by Dr. D. W. Beistel and his coworkers lead to the synthesis of the corresponding benzoate esters. In the present work the nature of ionic species formed in mixtures of sulfuric acid and 2,4,6-trimethoxybenzoic acid was examined, The spectral data suggest the presence of species similar to those assigned for the previous trisubstituted analogs, together with a species capable of fluorescence in the 2400 Å region. The reason of this unprecedented fluorescence has not been established"--Abstract, Page …


Evaluation And Application Of Dye Tracers In Karst Terrain For Determining Aquifer Characteristics, Milton Frank Bradley Jan 1970

Evaluation And Application Of Dye Tracers In Karst Terrain For Determining Aquifer Characteristics, Milton Frank Bradley

Masters Theses

"As ground water becomes increasingly important as a source of water in the United States, reliable information on the hydrological characteristics of carbonate aquifers must be obtained in order to develop them intelligently. Various tracers have been used in the past to determine if two or more points are connected hydrologically. Today there exists a number of excellent dye tracers and tracer methods have been developed in unconsolidated and clastic aquifers for determining hydrological characteristics. This paper reviews the various dye tracers and methods which might be applied in a carbonate karst terrain using wells as injection and sampling points. …


Man And His Environment: The Ecological Limits Of Optimism, R. S. Miller, G. M. Woodwell, W. R. Burch, P. A. Jordan, R. L. Means Jan 1970

Man And His Environment: The Ecological Limits Of Optimism, R. S. Miller, G. M. Woodwell, W. R. Burch, P. A. Jordan, R. L. Means

Yale School of the Environment Bulletin Series

No abstract provided.


Natural Variation In Susceptibility Of Pinus To Neodiprion Sawflies As A Basis For The Development Of A Breeding Scheme For Resistant Trees, Walter R. Henson, Louis C. O'Neil, Francois Mergen Jan 1970

Natural Variation In Susceptibility Of Pinus To Neodiprion Sawflies As A Basis For The Development Of A Breeding Scheme For Resistant Trees, Walter R. Henson, Louis C. O'Neil, Francois Mergen

Yale School of the Environment Bulletin Series

No abstract provided.


Groundwater Flow In Part Of The Little Missouri River Basin, North Dakota, Thomas M. Hamilton Jan 1970

Groundwater Flow In Part Of The Little Missouri River Basin, North Dakota, Thomas M. Hamilton

Theses and Dissertations

The Little Missouri valley in western North Dakota is deeply incised into slightly permeable Mesozoic and Cenozoic sediments. An evaluation of the groundwater flow in part of this valley was 'based on the present groundwater flow-system models. Abrupt changes in the hydrochemical facies have been explained relative to a continuous flow system.

The Little Missouri valley ls the discharge area of a regional groundwater flow system; it affects the potential distribution of the flow system for a minimum of 1.000 feet below the valley floor. The discharge area is approximately the same width as the valley floor and has a …


Apparatus For Dielectric Constant Measurements And Measurements For Water-Methanol Mixtures, James O. Wear Jan 1970

Apparatus For Dielectric Constant Measurements And Measurements For Water-Methanol Mixtures, James O. Wear

Journal of the Arkansas Academy of Science

A system for measuring dielectric constants has been constructed using a Sargent Oscillometer and an air bath for temperature control. The design and construction of the air bath as well as the temperature control achieved with it are described. The overall performance of the system including a computer program for forming the calculations is described. The system is one that requires calibration using two or more standard solvents and is good for both conducting and non-conducting liquids. Data are presented for water-methanol mixtures at 25 degrees with several points near pure methanol and also near pure water


Formulation And Solution Of Transient Flow Of Water From An Infiltrometer Using The Kirchhoff Transformation, Roland W. Jeppson Jan 1970

Formulation And Solution Of Transient Flow Of Water From An Infiltrometer Using The Kirchhoff Transformation, Roland W. Jeppson

Reports

No abstract provided.


Transient Flow Of Water From Infiltrometers--Formulation Of Mathematical Model And Preliminary Numerical Solutions And Analyses Of Results, Roland W. Jeppson Jan 1970

Transient Flow Of Water From Infiltrometers--Formulation Of Mathematical Model And Preliminary Numerical Solutions And Analyses Of Results, Roland W. Jeppson

Reports

The partial differential equation initial-boundary value problems which describe the three-dimensional axisymmetric flow of water from an infiltrometer through partially saturated soil are solved by finite differences using the alternating direction implicit method. Pertinent features which describe the flow characteristics obtained from 34 solutions for varying initial conditions and for 12 soil types are summarized in tables and figures. Relationships between such features as depth of penetration and lateral movement of the wetting front and rate of application and initial hydraulic head or tension in the soil are developed for several of these soils types from analyses of the results.


Solution To Transient Vertical Moisture Movement Based Upon Saturation--Capillary Pressure Data And Modified Burdine Theory, Roland W. Jeppson Jan 1970

Solution To Transient Vertical Moisture Movement Based Upon Saturation--Capillary Pressure Data And Modified Burdine Theory, Roland W. Jeppson

Reports

Using finite differences and the Crank-Nicholson implicit scheme for solving parabolic type partial differential equations, a computer program has been developed for solving the one-dimensional, vertical movement of water in soils. The formulation of the initial boundary value problem is obtained by introducing a new dependent variable through the Kirchoff transformation to replace the hydraulic head. Data relating saturation (or moisture content) to the capillary pressure in the soil are used to define the hydraulilc properties of the soil which are needed in order to obtain a solution. The Burdine Theory has been implemented in the program to obtain the …


Computer Simulation Of The Hydrologic-Salinity Flow System Within The Upper Colorado River Basin, M. Leon Hyatt, J. Paul Riley, M. Lynn Mckee, Eugene K. Israelsen Jan 1970

Computer Simulation Of The Hydrologic-Salinity Flow System Within The Upper Colorado River Basin, M. Leon Hyatt, J. Paul Riley, M. Lynn Mckee, Eugene K. Israelsen

Reports

Changes in the hydrologic equilibrium of a river basin resulting from resource development also produce changes in the quality pattern. Since the burden of quality maintenance must be shared by users (just as are quantities) predictions are needed for quality changes which might result from contemplated development at any specified location within the river system. This study reports the development of a computer simulation model of the water and salt flow systems within the Upper Colorado River basin. Because of the close relationship between the hydrologic and salinity flow systems, an understanding of the hydrologic system is essential to successful …


A Hydrologic Model Of The Bear River Basin, Robert W. Hill, Eugene K. Israelsen, A. Leon Huber, J. Paul Riley Jan 1970

A Hydrologic Model Of The Bear River Basin, Robert W. Hill, Eugene K. Israelsen, A. Leon Huber, J. Paul Riley

Reports

As demands upon available water supplies increase, there is an accompanying increase in the need to assess downstream consequences resulting from changes at specific locations within a hydrologic system. The problem is approached in this study by hybrid computer simulation of the hydrologic system. Modeling concepts are based upon the development of basic relationships which describe the various hydrologic processes. Within a system these relationships are linked by the continuity-of-mass priciple which requires a hydrologic balance at all points. Spatial resolution is achieved by considering the modeled areas as a series of subbasins. The time increment adopted for the model …


Bacterial Absorption On Soils--Thermodynamics, David W. Hendricks, Frederick J. Post, Deorao R. Khairnar, Jerome J. Jurinak Jan 1970

Bacterial Absorption On Soils--Thermodynamics, David W. Hendricks, Frederick J. Post, Deorao R. Khairnar, Jerome J. Jurinak

Reports

Laboratory studies on the adsorption of bacteria onto soils and activated carbon were undertaken to evaluate the role of the process in removal of bacteria from groundwater. It was hypothesized that removal of bacteria from water passing through soil would be primarily due to adsorption in which case the bacteria would behave in a manner similar to colloidal particles or chemical molecules. The basic kinetics of uptake of Staphylococcus aureus were determined on activated carbon, a highly adsorbing material chemically speaking. Once the technique was worked out and adsorption demonstrated to take place, sand, clay, and Mendon silt loam were …


Publications Of The Utah Water Research Laboratory, Utah Water Research Laboratory Jan 1970

Publications Of The Utah Water Research Laboratory, Utah Water Research Laboratory

Reports

No abstract provided.


The Function Of Social Behavior In Water Resource Development , Wade H. Andrews, Dennis C. Geertsen Jan 1970

The Function Of Social Behavior In Water Resource Development , Wade H. Andrews, Dennis C. Geertsen

Reports

Preface: This report is an analysis of a social survey of the middle and lower Bear River Basin of southeastern Idaho and northern Utah concerning the problem of water resource development in a semiarid region of the Western United States. The survey part of the study, carried out in the summer of 1966, dealt with both general social factors and a specific proposal made by the Bureau of Reclamation for developing water resources of the Bear River. In many respects this proposal and the resulting behavior is typical of other western river basin projects, in some other ways, however, it …


A Theoretical Study Of Infiltration Into Range And Forest Soils, Joel E. Fletcher, Yehia Z. El-Shafei Jan 1970

A Theoretical Study Of Infiltration Into Range And Forest Soils, Joel E. Fletcher, Yehia Z. El-Shafei

Reports

More than 400 rainfall simulator experiments were examined to detect which soil properties could be used to computer infiltration time relationships. Three theoretical equations were tested to determine their efficacy for calculating infiltration time relationships from soil and site characteristics. It was shown that both the modified Green and Ampt and Fletcher equations could by successfully used. Darcian type equations were developed on laboratory type samples which would show the relations between soil, solution and rainfall properties and infiltration. These latter equations have not been tested on undisturbed soils but give excellent agreement between measured and computed values for time …