Digital Commons Network^™

Magnetic Solid-Phase Extraction Of Trace Cobalt(Ii) On Iron Oxide-Hexagonal Boron Nitride In Water And Food Samples, Mustafa Soylak, Ali Mohammednour Ali Mohammed, Furkan Uzcan

Turkish Journal of Chemistry

Determination of trace cobalt(II) (Co(II)) in real samples remains challenging because of its very low concentration and strong matrix interferences. In this study, a simple and green magnetic solid-phase extraction (mSPE) method was developed for the selective separation and preconcentration of Co(II) ions using a newly designed iron oxide/hexagonal boron nitride (IOhBN) nanocomposite. The material was synthesized through a one-step, surfactant-free coprecipitation process, combining the high surface area, stability, and layered structure of hBN with the magnetic and reactive features of Fe₃O₄ nanoparticles. This hybrid structure provided abundant active sites and rapid magnetic separability, enabling efficient extraction within 5 min …

The Electrochemical Behavior Of The Lead-Thallium System In Acidic Sulfate Solutions, Pedro Juan Aragon

Doctoral Dissertations

"Although the literature involving the corrosion of pure lead in sulfuric acid solutions is extensive, such studies still constitute an active field of investigation and debate. Much of the effort expended on this subject is due to the need of a better understanding of the reaction in lead storage batteries as well as of the mode of electrocrystallization processes. The resistance of lead to attack by sulfuric acid renders it an important coating material in this media. It is also often used in electrochemical synthesis because of its overvoltage characteristics. Unfortunately its mechanical properties are poor, and many ways have …

Thermochemical Hydrogen-Deuterium Isotope Effects, Wayne C. Duer

Doctoral Dissertations

"The heats of solution at 25.0 ± 0. 1°C for each member of hydrogen-deuterium isotopic pairs (chloroform/chloroform-d, acetone/acetone-d₆, methanol/methanol-d₁, ethanol/ethanol-d₁, and water/heavy water) have been determined as a function of molality in a variety of solvents. The heats for most of the systems could be described as a linear function of average molality with an average deviation in fit of less than one per cent. Using these linear equations, heats of solution at infinite dilution were obtained by extrapolation to zero molality. The heats of solution at infinite dilution of the hydrogen containing compounds were subtracted from those of the …

An Experimental And Theoretical Study Of The Nucleation Of Water Vapor On Ions In Helium And Argon, Daniel R. White

Doctoral Dissertations

"The nucleation of water vapor on ions in atmospheres of helium and argon was studied using an expansion type cloud chamber. Separation of the positive and negative ions was achieved so that the nucleation could be studied as a function of both the sign of the ionic charge and the supersaturation. A semiphenominological theory was developed as an extension of the classical theory to include the effects of the ionic charge on the nucleation process. The theoretical model of the prenucleation embryo was assumed to possess an oriented dipole surface layer with the direction of orientation dependent on the sign …

A Study Of Far Infrared Grid Filters, Harold Victor Romero

Doctoral Dissertations

"The diffraction theory for the transmission of electromagnetic fields through a grid in a dielectric is derived and experimentally checked in the visible wavelength region. In the far infrared, an approximate mathematical representation is found to describe the grids in dielectrics. The empirical equations in the far infrared are combined with the electrical circuit-transmission line analog for inductive grids. Detailed structure of the transmittance versus wave number curves are presented. Then the theory of multielement grid filters is derived and compared with experiment. The properties of the filters can be predicted from a knowledge of the characteristics of the individual …

Identification Of Decomposition Products Of Tropyl Azide And Interaction Of Tropylium Ion With Nucleophiles, James Joseph Ward

Doctoral Dissertations

"An investigation of the structures of several of the products resulting from the decomposition of tropyl azide (I) and of the chemistry of related processes has been undertaken. Irradiation of samples of (I) in the vapor phase with low intensity UV G.E. Sun Lamps furnished a low melting white solid identified as tropyl troponimmonium azide (II). Earlier experiments of a similar nature reported to furnish (III) were not repeatable (Chem. Commun 276 (1967))...

Upon standing, solutions of (I) slowly formed troponimmonium azide (IV) in the cold (J. Chem. Soc. (D), 220 (1970)). The structures (II) and (IV) were confirmed by …

Realistic Impulsive P Wave Source In An Infinite Elastic Medium, Joseph Hugo Hemmann

Doctoral Dissertations

"The generally assumed instantaneous impulsive pressure sources for an elastic P wave in an infinite medium lead to basic contradictions, a step function source yielding infinite displacements as the shear modulus goes to zero, and the total energy radiated by a delta function (or any derivative of the delta function) source being infinite. By noting that the character of the solution in the elastic region must match the acoustic case near the source, a realistic impulsive pressure source is postulated which has a finite time history. The elastic field produced by this source is then obtained in closed form. A …

The Surface Effects Of Alkali Halides In The Infrared, Vincent Joseph Llamas

Doctoral Dissertations

"The surface state extension of the shallow donor theory is reviewed. The surface state theory and its applications to F-centers of alkali halides is presented. Experimental infrared data show an absorption which seems to correspond with the ground state to first excited state transition. Surface state concentrations of F-centers as a function of depth into the crystal are given. The ratio of surface to bulk cross sections in KBr and experimental calculations of effective masses in various alkali halides are in excellent agreement with theory. The theoretical cross sections are derived from transition probabilities. However, lack of excited states, the …

The Anodic Oxidation Of Oxalic Acid On Au, Jean Louis Lucien Desmartin

Masters Theses

"The anodic oxidation of oxalic acid on Au has been studied at 25ºC in aqueous media. The reaction rate was measured as a function of potential, oxalic acid concentration, pH, and temperature in H₂SO₄-K₂SO₄ solutions. A change in the Tafel slope in going from the lower to the higher Tafel region is explained by an alteration of the reaction mechanism due to electrical interactions between adsorbed species and the anode. Further details of an oxidation sequence involving resonant forms of oxalic acid are proposed"--Abstract, page 1.

A Study Of The Oxygen Exchange Between Chromate Ion And Water, James Hsiao-Hsin Chiang

Masters Theses

"The kinetics of the isotopic exchange reaction between O¹⁸-enriched chromate ion and solvent water have been measured as a function of pH and chromate ion concentration. The exchange kinetics can be explained in terms of the dimerization equilibria HCrO_4̄ + Cr₂O[subscript 7 with double dash above] [double arrows] Cr₂O[subscript 7 with double dash above] + OH⁻ and 2HCrO_4̄ [double arrows] Cr₂O[subscript 7 with double dash above] + H₂O except at high pH, where it is independent of pH. Rate constants at 30ºC for the reactions of the dimerization equilibria and the first order reaction at the high pH …

Enhanced Evaporation Of Water Droplets Due To Surface Contamination, Robert Bernard Hughes

Masters Theses

"Experimental evidence for enhanced evaporation of small (3-9 µ radius) water droplets are presented. Both "pure" droplets and droplets contaminated with surface active materials fell into air of known relative humidity (96-99 per cent) at an ambient temperature of 29.9C and evaporated. The rates of evaporation were determined by photographing the evaporating drops, measuring the distance a drop fell during a fixed time interval, and applying Stokes law. The contaminated droplets exhibited a rate of evaporation 1.8µ² sec⁻¹ faster than "pure" drops. This can be compared with rates for pure drops of 1.9 and 5.7µ² sec⁻¹ at 0.1 and 0.3C …

Metabolism Of 3-Iodotyrosine And 3,5-Diiodotyrosine By Thyroid Extracts, Shih-Ying Sun

Masters Theses

"A porcine thyroid enzyme was extracted from thyroid tissue by homogenization and differential centrifugation. The enzyme was capable of metabolizing both 3-iodotyrosine and 3,5-diiodotyrosine. All of the thyroid subcellular particles produced a fluorescent compound when incubated with these substrates. When the 1,000 x g sediment was supplemented with the 48,000 x g supernatant a second compound was formed. The compound was UV absorbing and has been identified as either 3-iodo-4-hydroxybenzaldehyde or 3,5-diiodo-4-hydroxybenzaldehyde depending upon which substrate was used. The 1,000 x g sediment was solubilized with 1% Conoco 1012-6 detergent. The activating factor in the 48,000 x g supernatant was …

A Study Of The Esterification Of 2,2,4,4-Tetramethyl-1,3-Cyclobutanediol, Lewis Metzler Naylor

Dissertations and Theses @ UNI

The purpose of this research was to prepare, identify, and characterize 2,2,4,4-tetramethyl-1,.3-cyclobutanediol bischloroacetate using 2,2,4,4-tetramethyl-1,3-cyclobutanediol and monochloroacetic acid as starting materials. The synthesis of this diester has not been reported previously.

Catalyzed and uncatalyzed reactions were attempted, with the uncatalyzed having, in general, the better yield. The diester, trans-2,2,4,4-tetrametbyl-1,3-cyclobutanediol bischloroacetate (mp, 103.5-104; n²², 1.516-1.520), was isolated from a mixture of the isomers. The trans configuration of the diester was confirmed by comparing known nuclear magnetic resonance spectra to that of the diester. Infrared spectroscopy was used to confirm functional groups. Standard analytical techniques were used to determine chloride …

Fisheries Report No V (5) - Report On Marron In Farm Dams (Cherax Tenuimanus), N M. Morrissy

Fisheries Research Reports

A programme of selling marron (Cherax tenuimanus) to country dwellers for stocking farm dams, has been carried out by the Pemberton Trout Board for the past few years with considerable financial gain. In this case permission to sell the marron was granted by the Department of Fisheries and Fauna so as to encourage the provision of stocks of this large, freshwater crustacean for farmers in the dryer inland areas of the Southwest which are remote from sources of fresh fish and from natural stocks of marron.

The marron, however, have been sold indiscriminately, upon request, without any advice as to …

Virus Movement In Groundwater Systems, William A. Drewry

Arkansas Water Resources Center Technical Reports

The purpose of this study is to investigate the extent to which soil acts as an agent in the transmission of waterborne viruses. Since many waterborne outbreaks of viral diseases have involved small wellwater supplies contaminated by effluents from subsurface wastewater disposal systems, there is a great need for such information. Results of this study show that virus adsorption by soils is greatly affected by the pH, ionic strength, and soil-water ratio of the soil-water system and various soil properties. Also, it is shown that one cannot predict the relative virus adsorbing ability of a particular soil based on the …

The Effects Of Herbicides On Three Soil Inhabiting Blue Green Algal Species, Lee C. Darlington

All Master's Theses

The object of this study was to examine the effects of varying concentrations of 2, 4-D, Dalapon, and Tordon on the growth of several nitrogen-fixing blue-green algal species obtained from soil samples and grown under culture conditions in the laboratory.

Estimations Of The Effective Electrolytic Surface Area Of Rough And Porous Silver Electrodes ; Ii. Potentiostatic Oxidation Of Silver In Alkaline Electrolyte, James Glenn Bearss

Theses and Dissertations

This dissertation is written in two sections. The first section deals with the development of methods for the estimation of the effective electrolytic surface area of rough and porous silver electrodes in alkaline electrolyte. Data are presented comparing the results of three different methods of surface area estimation. Model pore electrodes were also prepared and oxidized to study the reactions in a pore. Data for constant current oxidations of these electrodes is given. The second section deals with the potentiostatic oxidations of silver in alkaline electrolyte. Data are presented on the total charge acceptance versus applied potential for a potential …

Technical Assistance To The Commerical Fisheries Statistics Project Of Puerto Rico (Final Report)., Charles W. Caillouet, James B. Higman

RSMAS Technical Reports

In the first fiscal year of this project, the Institute of Marine Sciences, University of Miami, Florida, and the Department of Agriculture, Commonwealth of Puerto Rico, under Public Law 88-309, began development of a program of continuous collection of statistical information on the quantity and value of landings of commercial marine fishes and shellfishes from Puerto Rican coastal waters (Caillouet, Garcia and Higman, 1968).

Chemistry Of The Oxidant, Ferrate, Its Interaction With Specific Organics Found In Waste Water, Donald H. Williams, J. T. Riley

KWRRI Research Reports

It became obvious during this investigation that while much work has been done with ferrate (VI) chemistry, discrepancies existed in the literature and very little attention had been given possible engineering uses. This work attempted to fulfill these two needs in an exploratory manner.

The preparative techniques were reviewed and mechanical improvements made in one which allowed improved yields. Essentially what was done was to enlarge and improve the filtering technique of the product and use cooler temperatures throughout the preparation. This greatly shortened the time required. Then it was learned that the addition of ethyl alcohol to the final …

A Thermogravimetric Study Of Polyvinylidene Chloride In Polymers, Charles Edward Singleton

Master's Theses

In the manufacturing of thin films such as cellophane, polymers employed as coatings greatly improve film functionality. Polymers such as polyvinylidene chloride, polyvinyl chloride, polyvinyl acetate and many others are used as coatings or components of coatings designed to improve the functionality of a film. Selection of polymers with properties that will meet the requirements of the finished film product is a continuing process of film manufacturers. Physical and chemical characterization of the polymer along with coating functionality are the factors involved in the selection. Chemical composition is the most important factor affecting polymer characteristics and must be known if …

Water Resources News, Volume 1, No. 3, July 1969

Water Current Newsletter

Evapotranspiration Seminar
Legislation of Interest
Publicatons of Interest
Data Bank Bill Passed
Phreatophyte Research Grant Obtained
OWRR Fiscal Year 1970 Title II Program
Research Review

The Oxidative Decarboxylation Of Polyaminocarboxylic Acids - I. A Study Of The Reaction Of Ethylenedinitrilotetraacetic Acid (Edta) With Cerium (Iv) In Acid Solution, Samir B. Hanna, S. Al-Hashimi, William H. Webb, William R. Carroll

Chemistry Faculty Research & Creative Works

The reaction between Ce(IV) and EDTA was followed titrimetrically and spectrophotometrically and was found to occur in stages. Four equivalents of Ce(IV) are reduced per mole of EDTA almost instantaneously at room temperature. With increasing temperature and reaction time an ultimate of about 14 equivalents of Ce (IV) is consumed per mole of EDTA. Carbon dioxide, formaldehyde, and other yet unidentified compounds are the products of oxidation of EDTA. The kinetics of the reaction in aqueous sulfuric acid was studied over the temperature range 11.7°-40°C by a spectrophotometric technique. The effects of the acidity of the medium and of added …

Subsurface Irrigation Research In Arkansas, John P. Hoskyn, Billy B. Bryan

Arkansas Water Resources Center Technical Reports

A pilot study conducted in 1963 indicated that (1) cotton yields could be increased by subirrigation, (2) drilled orifices were unsatisfactory because of internal plugging caused by burrs and drilling particles, and (3) operating pressures of 5 and 10 psi were excessive, and 5 psi probably should be considered as an upper-limit pressure. A greenhouse study of a subirrigation system indicated that 2 psi should, in general, for in-wall orifices, be considered as a lower-limit pressure when orifices are built into the pipe wall. The greenhouse study also indicated that a placement depth of 12 inches was preferable to 18 …

Syntheses Via Modifications Of The Knorr-Paal Procedure :|Ba. Derivatives Of 2,6-Dioxa-10-Azatricyclo[5.2.1.0[Superscript 4,10]]Decane ; B. Highly Sterically Crowded 1,2,5-Trialkylpyrroles And Pyrrolidines, Weldron Severin Burnham

Theses and Dissertations

Earlier work in these laboratories on the heterotricyclic system 2,6-dioxa-10-azatricyclo[5.2.1.04,10]-decane, formed from 1,4-diketones and 2-amino-1,3-propanediols by a product-water-azeotroping procedure, was extended with the synthesis of analogous compounds, e.g., the 1,4,7-triethyl-, 1,7-dimethyl-4-isopropyl-1,7-diethyl-4-isopropyl-, 1,7-dimethyl-3- and 4-phenyl- compounds. The 1,7-dimethyl heterotricycle, the kinetically-controlled product, was accompanied by the thermodynamically-controlled product, 2-(2,5-dimethyl-1-pyrryl)-1,3-propanediol. The 1,7-diethyl heterotricycle was also accompanied by the isomeric pyrrole as were the 1,7-dimethyl-3- and 4-phenyl compounds. A scheme postulating a common intermediate is presented. The interesting analogous compounds, 1,7-dimethyl-2-oxa-6-thia-10-azatricyclo[5.2.1.04,10]decane, 1,4,7-trimethyl-2,6-dioxa-11-azatricyclo[5.3.1.04,11]undecane and 11-hydroxymethyl- and 11-methyl-9,13-dioxa-14- azatetracyclo[6.5.1.02,7 011,14]tetradeca-2,4,6-triene were also prepared. The syntheses in good yields of a considerable number of moderately to …

Glycosidic Enzymes Of The Tropaeolum Majus, Donald Richard Snowden

All Master's Theses

The purpose of this study is to investigate the hydrolytic enzymes of Tropaeolum majus. This particular plant is the only example of the Tropaeolum genus found in the northern hemisphere. It is the well-known Indian cress or common garden nasturtium.

The Effect Of Selected Nurse-Patient Contacts On The Attendance Of Non-Private Patients At Preparation For Childbirth Classes, Judith A. Hart

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine whether selected nurse-patient contacts effected the attendance of non-private patients at Preparation for Childbirth classes. During the data collection period only six of the eight patients who met the criteria for this study were available. Each of the six patients was reached by at least one of the three types of nurse-patient contacts-- a letter of invitation to the Preparation for Childbirth classes, weekly contacts with the patients at the classes and three home visits to each patient. Tools used to collect data for this study were a personal information questionnaire, home …

Catalytic Effect Of Soil Components On The Nitrite Transformation In Buffer Acid Solutions, Laxman G. Kuratti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrite decomposition in buffer solutions of pH 3, 4, and 5 was observed to be a first order reaction with rate constants (k) 6.39 x 10^-3, 1.15 x 10^-3, and 0.17 x 10^-3, respectively. When 10 grams of two different soils were introduced, the reaction was catalyzed in all three pH conditions studied. This effect, however, was more pronounced in pH 5.

When 10 grams of soil were introduced, all the added nitrite was not recovered. The deficit ranged from 17 to 30 parts per million when 150 parts per million nitrite nitrogen was …

The Ias Bulletin, V3n1, January 1969, Iowa Academy Of Science

IAS Bulletin

"

In this issue:

--- Call for Papers
--- Visiting Scientist Program
--- Speakers' Bureau Directory
--- Special Committee Named
--- State-Wide Articulation Committee Appointed
--- Report fromthe ISTS Short Course Committee
--- Constitution Revision
--- Industrial Support Being Solicited
--- Special Bulletin Going Out to all High School Science Teachers
--- Membership Information
--- Academy Representatives Attend AAAS Convention
--- Proceedings for 1967 and 1968
--- Research Grants Awarded
--- New Section to Appear on the 1969 Program
--- Program Notes from Other Sections
--- Eighty-First Session at Cedar Falls
--- Call for Nominations for Teacher Awards
--- Selected …

The Persistence Of Pesticides In Impounded Waters, Robert A. Lauderdale

KWRRI Research Reports

The purpose of this study was to investigate the persistance of the insecticides aldrin, dieldrin, chlordane, and DDT in water. A small drainage area was sprayed with these compounds, and the insecticides were collected in the runoff water from the area. Laboratory experiments were performed to determine the effectiveness of aeration, adsorption on silt, and adsorption on algae in removing the pesticides from water.

All of the pesticides were found in samples of water collected from the area for the full period of the tests. The amounts which were found in a small pond into which the surface water drained …

A Study Of Earth Science Teachers And Practices In North Dakota For The Academic Year 1968-1969, Howard C. Reith

Theses and Dissertations

In the period between 1961-1964 the North Dakota department of Public Instruction initiated long overdue changes in the science curriculum for the seventh, eighth, and ninth grades of the public schools. Titese involved changes from general science to the life, earth, and physical sciences. During this same period there was a re vitalization of interest in earth science at the national level, with the public school enrollment rising from several thousand to well over one million.

Because of the rapid national growth in earth science enrollment, and the status of earth science in North Dakota, a study to determine the …