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Articles 21511 - 21540 of 22384
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Thermodynamics Of Proton Dissociation And Metal Ion Complexation In Aqueous Solution. I, Cation Binding With Cyclic Polyethers: Significance In Ion Transport Processes. Ii, Proton Dissociation From Adenosine, Several Monosaccharides And Related Compounds. Iii, Proton Dissociation From Several Pyrimidines And Their Nucleosides At 10, 25 And 40°, Joseph Howard Ryttling
Theses and Dissertations
The log K, ΔH° and ΔS° values for the interaction of several metal ions with the two isomers of the cyclic polyether, 2,5,8,15,-18,21 hexaoxatricyclo[20.4.0.0^9,14]hexacosane are reported. The stability order found for alkali metal ion interaction with either isomer is identical to the order of ion permeability through reconstituted biological membranes for structurally related antibiotics. The size of the metal ion is critical in determining the extent of interaction. A calorimetric titration study of proton ionization from several monosaccharides and derivatives, pyrimidine bases and their nucleosides, adenosine and its derivatives, and cycloheptaamylose is described. The heats of reaction obtained in this …
A Study Of Folic Acid Dependent Reactions In Bovine Brain, Dillard Spencer Broderick
A Study Of Folic Acid Dependent Reactions In Bovine Brain, Dillard Spencer Broderick
Theses and Dissertations
The enzymatic interconversion of serine to glycine and N5, N10-methylene tetrahydrofolate to N5 -methyl tetrahydrofolate have been studied in a cell-free system derived from bovine brain. A partial purification of serine transhydroxymethylase and N5, N10 -methylene tetrahydrofolate reductase has been achieved by ammonium sulfate fractionation, protamine sulfate fraction, and by various column chromatography procedures. The two enzymes studied catalyze sequentially the reductive transfer of the hydroxymethyl group of serine to the N5 position of tetrahydrofolate forming N5 -methyl tetrahydrofolate. The products of these reactions were assayed by the incorporation of C14 from a one-carbon precursor i.e., L-beta-(C14)-serine, or N5 -methyl …
Wisconsin Power Mechanics Course Of Study, Donavan L. Jones
Wisconsin Power Mechanics Course Of Study, Donavan L. Jones
Theses and Dissertations
No abstract provided.
The Catalytic Hydrogenation Of Benzodiazines.|Ni.|Pphthlazine.|Nii.|Pquinazoline, Danny Lee Elder
The Catalytic Hydrogenation Of Benzodiazines.|Ni.|Pphthlazine.|Nii.|Pquinazoline, Danny Lee Elder
Theses and Dissertations
Quinazoline and phthalazine were hydrogenated at low pressure and temperature (60 psi, room temperature) and high pressure and temperature (2000 psi, 100°C, 150°C} in neutral and acidic solvents over 5% Pd/C, 5% Ru/C, 5% Rh/Al2O3 , 5% Rh/C, and 5% Pt/C. Chromatographic methods for determining the qualitative and quantitative composition of hydrogenation mixtures were developed. The compositions of quinazoline and phthalazine-hydrogenation mixtures were determined. Eight phthalazine-hydrogenation products were detected and isolated: (1) 1,2-dihydrophthalazine, (2) 1,2,3,4-tetrahydrophthalazine, (3) a,a'-diamino-o-xylene, (4) o-methylbenzylamine, (5) 1,3-dihydroisoindole, (6) o-xylene, (7 and 8) cis- and trans- 1,2-dimethylcyclohexane. These products were identified by isolating them from reaction mixtures …
Optimization Of Physical Properties Of Hydraulic Cushion Cells For Vehicle Impact Restraint, William Evans Hughes
Optimization Of Physical Properties Of Hydraulic Cushion Cells For Vehicle Impact Restraint, William Evans Hughes
Theses and Dissertations
In recent years, the United States has witnessed a vast expansion of its internal highway system. Concurrently the number of vehicles has increased as has the average yearly milage per vehicle. Unfortunately, along with increased vehicle use there has been an alarming increase in annual loss of life and property due to traffic accidents. Statistics verify that the modem freeway systems greatly reduce dangerous head on collisions but the rate of accidents due to collisions with fixed objects in or near the roadway has increased almost 50 percent in the past thirty years.^1 In 1966, about 13>300 deaths were …
Solid-Liquid Phase Equilibria Of The Sodium-Rubidium And Sodium-Potassium-Rubidium Alloy Systems, Chen-Chao Hsu
Solid-Liquid Phase Equilibria Of The Sodium-Rubidium And Sodium-Potassium-Rubidium Alloy Systems, Chen-Chao Hsu
Theses and Dissertations
Thermal methods were used, to determine with high precision, the solid-liquid phase equilibria diagrams for the sodium-rubidium and sodium-potassium-rubidium systems. In the sodium-rubidium system, the results differ greatly from those of earlier works, especially near the eutectic composition where differences in freezing points as large as 25°K occur. A detailed search was made for possible intermetallic compounds (especially Na2Rb). Neither slow temperature cycling in the temperature range where compound formation could occur nor extended periods of annealing just above the eutectic temperature produced any evidence for compound formation in the sodium-rubidium system. A 2:1 (sodium to rubidium) sample was subjected …
Mechanism Of Water Transport Through Reverse Osmotic Membranes, Cheryl Kay Murphy
Mechanism Of Water Transport Through Reverse Osmotic Membranes, Cheryl Kay Murphy
Theses and Dissertations
Cellulose acetate membranes show a higher permeability to water than to salt and are being used for desalination of salt water by reverse osmosis. Use of highly acetylated cellulose membranes give a higher salt rejection but also decrease flow rate of the water. The addition of very-short-chain substances or alkyl groups larger than one carbon atom to the cellulose membrane also decreases water flux. A proposed mechanism of transport through the membrane is that the water molecule is passed along the chain by hydrogen bonding with the acetyl groups, The NMR shows a change in the chemical shift of water …
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
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 …
Selected Variables Related To Academic Achievement Of American And Canadian Male Freshmen At The University Of North Dakota, William E. Grady
Selected Variables Related To Academic Achievement Of American And Canadian Male Freshmen At The University Of North Dakota, William E. Grady
Theses and Dissertations
Problem: The purpose of this study was to determine the relationship of various academic, personality, and biographical factors to the academic achievement of American and Canadian male college freshmen.
Procedure: The subjects employed in this study were 31 American and 31 Canadian male college freshmen enrolled at the University of North Dakota during the 1968-1969 academic year.
These students were administered the American College Test immediately preceding the beginning of the fall semester. During the semester each student was administered the Biographical Data Questionnaire, the Fundamental Interpersonal Relations Orientation- Behavior scale, and the Fundamental Interpersonal Relations Orientation-Feelings scale.
The statistical …
The Effectiveness Of Cognitive Conflict And Active Participation As Methods Of Inducing The Conservation Of Substance, Leila K. Beard
The Effectiveness Of Cognitive Conflict And Active Participation As Methods Of Inducing The Conservation Of Substance, Leila K. Beard
Theses and Dissertations
This study was concerned with the possibility of training for conservation. With the component elements held constant across all groups, the effectiveness of two methods of presentation, cognitive conflict and active participation, were tested by a pretest-training-posttest procedure using a 2 x 2 design with a common control group. Within the treatment groups, a conflict presentation of addition-subtraction and perceptual components was contrasted with a non-conflict presentation of the same addition-subtraction and perceptual components, each in a separate series. An active manipulation procedure was contrasted with passive participation. Results indicated that conservation responses increased within the treatment groups significantly more …
The Controlled Oxidation Of Lignite In A Fixed Bed, Leroy Dockter
The Controlled Oxidation Of Lignite In A Fixed Bed, Leroy Dockter
Theses and Dissertations
The use of cooling coils or pipes to control the reaction zone temperatures when oxidizing lignite in a fixed bed was studied. The experimental procedures involved passing heated air through a bed of lignite to initiate spontaneous heating and then removing the heat generated using a water cooled coil. Variables investigated included the lignite moisture content, prior oxidation history, and lignite source.
Spontaneous heating was initiated in lignite from three different mines, and at initial moisture contents from bed moisture down to 10 percent by heating the lignite to 250-260 °F while passing air slowly through the bed. At moisture …
High Pressure, High Temperature Syntheses Of Selected Lanthanide-Tellurium Compounds, John Francis Cannon
High Pressure, High Temperature Syntheses Of Selected Lanthanide-Tellurium Compounds, John Francis Cannon
Theses and Dissertations
High pressure, high temperature technics were employed to successfully synthesize HoTe1.7, ErTe1.7, TmTe1.7, LuTe1.7, YTe1.7, and LuTe3. The pressure-temperature regions in which synthesis of each compound is successful were determined. Pressures to 100 kbars concurrently with temperatures to 1200 °C were used in an attempt to prepare ScTe1.7 and ScTe3, but these efforts met with failure. X-ray studies of these new compounds confirmed that they are extensions of the LTe2-X (0≤x
Social Structure Of Small Mammal Populations At The National Reactor Testing Station, Idaho, R. Lynn Speth
Social Structure Of Small Mammal Populations At The National Reactor Testing Station, Idaho, R. Lynn Speth
Theses and Dissertations
This investigation examined the social structure of four species of small mammals (Perognathus parvus (Peale), Reithrodontomys megalotis (Baird), Peromyscus maniculatus (Wagner), and Dipodomys ordi (Woodhouse) at the National Reactor Testing Station (NRTS) in Idaho. An understanding of the social structure provides ecological clues concerning the integration of interactions, reproduction, distributions, densities, and diel activities for not only one animal and species, but for a complex of animals interacting with each other.
The Thermodynamics Of Transition Metal Chelation In Dilute Aqueous Solution.|Ni.|Pthe Thermodynamics Of Interaction Of Serinate Ion With Divalent Co, Ni, Cu, Zn, And Cd Ions In Aqueous Solution.|Nii.|Pthe Calorimetric Standardization Of Dilute Ferrous Ion Solutions For Use In Determining 2,2'-Bipyridine, Joseph Willard Richards
Theses and Dissertations
Calorimetrically determined ΔH° values are given for the stepwise formation of chelate species between serinate ion and the divalent metal ions of Co, Ni, Cu, Zn, and Cd. These values of ΔH° are compared with those reported in the literature and were combined with values of ΔG° (log K) found in the literature to calculate values of ΔS°. These values of ΔG° and ΔS° are listed also. A new method of standardizing dilute ferrous ion solutions is reported. This procedure makes use of the thermometric titration technique to detect the equivalence point for the reaction of K_2Cr_2O_7 with ferrous ion. …
The Use Made By Lds Institute Instructors Of Statements And Messages Of The Modern Prophets In Answering Current Issues Of Importance To College Students, Gale J. Brimhall
The Use Made By Lds Institute Instructors Of Statements And Messages Of The Modern Prophets In Answering Current Issues Of Importance To College Students, Gale J. Brimhall
Theses and Dissertations
This study was designed to evaluate the L.D.S. institute instructors use of statements made by leaders of the Church of Jesus Christ of Latter-day Saints. These leaders have instructed Church school teachers to teach what the prophets have said and not the teachers own ideas or views on doctrine.
The data from this study show the following: (1) Approximately twenty per cent of instructor responses in selecting the stated principles of the Church on a current issue are incorrect; (2) The ability of the instructors to recognize prophet's statements from non-prophet's statements is seventy-three per cent; (3) Over ninty per …
The Attitudes Of Parents In North Dakota Concerning High School Business Education, Constance C. Larson
The Attitudes Of Parents In North Dakota Concerning High School Business Education, Constance C. Larson
Theses and Dissertations
No abstract provided.
An Analysis Of The Requirements To Officiate Interschool Basketball Games In North Dakota, Brian C. Larson
An Analysis Of The Requirements To Officiate Interschool Basketball Games In North Dakota, Brian C. Larson
Theses and Dissertations
No abstract provided.
Tolerance Of Mice To Increased Oxygen And Nitrogen Pressures : Design Of A Dual High Pressure Chamber, Robert Eugene Thompson
Tolerance Of Mice To Increased Oxygen And Nitrogen Pressures : Design Of A Dual High Pressure Chamber, Robert Eugene Thompson
Theses and Dissertations
No abstract provided.
The Effect Of Cold Adaption On Liver Glycogen In The Rat, Donald R. Davis
The Effect Of Cold Adaption On Liver Glycogen In The Rat, Donald R. Davis
Theses and Dissertations
No abstract provided.
Fort Union (Paleocene) Mollusks From Southern Golden Valley And Southeastern Billings Counties, North Dakota, John J. Delimata
Fort Union (Paleocene) Mollusks From Southern Golden Valley And Southeastern Billings Counties, North Dakota, John J. Delimata
Theses and Dissertations
Nine molluscan species are known to occur in Tongue River Sentinel Butte sediments of parts of Billings, Golden Valley, and Slope Counties in southwestern North Dakota. Tongue River sediments contain all nine of the species which include: two unionids, Plesielliptio priscus (Meek and Hayden) and Rhabdotophorus senec tus (White); one corbulid, Bicorbula mactriformis (Meek and Hayden); and six viviparids, Viviparus retusus (Meek and Hayden), Viviparus trochiformis (Meek and Hayden), Campeloma nebrascensis (Meek and Hayden), Lioplacodes limnaefonnis (Meek and Hayden), Lioplacodes nebrascensis (Meek and Hayden), and Lioplacodes tenuicarinata (Meek and Hayden). Only five of these species (P. priscus, Q. nebrascensis, V. …
The Upper Red River Formation (Ordovician) In Western North Dakota, Harlan K. Friestad
The Upper Red River Formation (Ordovician) In Western North Dakota, Harlan K. Friestad
Theses and Dissertations
The upper Red River Formation in Western North Dakota consists of cyclic sedimentary rocks having four main porosity zones which contain most of the oil and gas found in the formation. It was divided into three distinct units that were traced throughout western North Dakota on mechanical logs. In ascending order these are the P, R, and F intervals which consist of alternating sequences of dolomites, limestones, and anhydrites. Facies changes, occur within the P interval both on a regional and a local scale, typically from dense limestones to porous dolomites.
The Kesson anticline and the basin hinge JJ.ne 1-1ere …
A Study Of Earth Science Teachers And Practices In North Dakota For The Academic Year 1968-1969, Howard C. Reith
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 …
A Comparison Of The Late Wisconsinan Molluscan Fauna Of The Missouri Coteau District (North Dakota) With A Modern Alaskan Analogue, Samuel J. Tuthill
A Comparison Of The Late Wisconsinan Molluscan Fauna Of The Missouri Coteau District (North Dakota) With A Modern Alaskan Analogue, Samuel J. Tuthill
Theses and Dissertations
Study of forty fossiliferous sites in late Wisconsinan sediments from the Missouri Coteau district in central North Dakota has defined the molluscan fauna of the period of geologic time between 12,000 and 9,000 C14 years before the present. The fauna includes twenty-eight taxa of nonmarine gastropods and bivalves and is dominated by branchiates. The modern molluscan fauna of the Missouri Coteau district in North Dakota lacks four species which were resident in the late Wisconsinan and contains no unionids, one additional aquatic species, and is strongly dominated by pulmonate gastropods.
The geology of the Missouri Coteau has been interpreted as …
Vector-Valued Functions, Thomas Wiggen
Analog To Digital Conversion, Arvind J. Dandekar
Analog To Digital Conversion, Arvind J. Dandekar
Theses and Dissertations
No abstract provided.
Internal-External Locus Of Control In Relation To Information Extraction, Lilly J. Schubert
Internal-External Locus Of Control In Relation To Information Extraction, Lilly J. Schubert
Theses and Dissertations
No abstract provided.
A Model System For The Deacylation Of Acylenzymes, Raymond Shih-Chao Sun
A Model System For The Deacylation Of Acylenzymes, Raymond Shih-Chao Sun
Theses and Dissertations
No abstract provided.
The Cubist Aesthetic Theories Of Pictorial Representation: An Analysis Of The Component Structure Of An Object To Create An Interior Reality, Sharon Lee Duvall
The Cubist Aesthetic Theories Of Pictorial Representation: An Analysis Of The Component Structure Of An Object To Create An Interior Reality, Sharon Lee Duvall
Theses and Dissertations
This paper is primarily an analysis of the Cubistic attitude toward pictorial reality. The project includes a study of form and structure in the Cubists* searoh for a conceptual reality. Twelve paintings of the author are presented each with explanations which reveal several similarities to Cubist thinking.
Some attention has been given to analytical and synthetic Cubism as well as to certain fundamentals of the movement. However, both a historical approach and biographical studies have been ignored. Because art is an aesthetic, this paper is not a problem- result type of study but an analysis in support of Cubism as …
Design Of A Control Transducer For An Upper Extremity Prosthesis, Richard Hoare
Design Of A Control Transducer For An Upper Extremity Prosthesis, Richard Hoare
Theses and Dissertations
No abstract provided.
A Theoretical Determination Of Heat Transfer Coefficients For Flows Induced By An Isothermal Cylinder Rotating In A Rarefied Gas, Julian J. Huang
A Theoretical Determination Of Heat Transfer Coefficients For Flows Induced By An Isothermal Cylinder Rotating In A Rarefied Gas, Julian J. Huang
Theses and Dissertations
No abstract provided.