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Articles 2701 - 2730 of 2906

Full-Text Articles in Physical Sciences and Mathematics

Isolation, Purification, Scanning Electron Microscopy And Bacterial Dna Uptake Of Plant Protoplasts, Bronwyn G. Hughes Apr 1977

Isolation, Purification, Scanning Electron Microscopy And Bacterial Dna Uptake Of Plant Protoplasts, Bronwyn G. Hughes

Theses and Dissertations

Protoplasts were isolated from tobacco and barley leaves in sucrose or mannitol using commercially available cellulases and macerozymes. Barley growth and protoplast isolation and purification conditions were optimized so that protoplasts were obtained in high yields free of unwanted debris and organelles. A technique for processing barley and tobacco protoplasts for examination by scanning electron microscopy was developed in which protoplasts seem to have maintained their structural integrity. Barley and tobacco protoplasts took up 3H-B. subtilis DNA, 125I-B. subtilis DNA or 125I-M. luteus DNA as a linear function of time (0-6 hr) and DNA concentration (0-200 μg/ml). Up to 16 …

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The Dependence Of The Apparent Pk Of Ion Exchange Celluloses Of Ionic Strength, Paul Cyril Gillespie Apr 1977

The Dependence Of The Apparent Pk Of Ion Exchange Celluloses Of Ionic Strength, Paul Cyril Gillespie

Theses and Dissertations

Diethylaminoethyl cellulose was titrated with acid and base in various concentrations of NaCl. The pK values were determined from titration curves using a graphical technique. Two titratable groups were observed from the acid titration curve, a major and a minor group. The minor group, which represented 20% of the acid titration, was barely detectable in the base titration curve and had a salt-independent pK of 6.0. The pK of the major group was strongly salt-dependent and was approximately a linear function of log N NaCl. An equilibrium shift caused by the counter ion may explain the salt dependence. Hydrogen bonding …

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Certain Edaphic And Biotic Factors Affecting Vegetation In The Shadscale Community Of The Kaiparowits Area, Vane Orlan Campbell Mar 1977

Certain Edaphic And Biotic Factors Affecting Vegetation In The Shadscale Community Of The Kaiparowits Area, Vane Orlan Campbell

Theses and Dissertations

A study area on the southern extensions of the Great Basin cold desert (Kaiparowits Basin, Utah) was selected which has had varying amounts of disturbance. Areas with similar slope and exposure in the Shadscale community were sampled. At each site, soil samples were collected and percent sand, percent clay, percent silt, soluble salts, and hydrogen ion concentrations were measured. Cluster analysis based on percent frequency of the perennial species showed that eight groups or sub-communities were definable within the area sampled. Patterns within the vegetation were shown to be independent with the use of cluster analysis. Discriminant analysis on soil …

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Intermolecular Potential Surfaces From Electron Gas Methods. Ii. Angle And Distance Dependence Of The A’ And A” Ar–No(X^2ii) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack Feb 1977

Intermolecular Potential Surfaces From Electron Gas Methods. Ii. Angle And Distance Dependence Of The A’ And A” Ar–No(X^2ii) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack

Faculty Publications

Angle dependent intermolecular potential energy surfaces for the two states (2A’ and 2A”) that arise from the interaction of ground (X^2II) state NO with Ar are calculated using the electron gas model to obtain the short range interactions. The average and difference of the two interaction energies are fit to analytic forms convenient for use in scattering calculations and joined smoothly onto the long range van der Waals potential previously determined. The results, which appear to be of useful accuracy, and the applicability of the electron gas model to such open shell–closed shell interactions are discussed.

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Voltammetric And Electrochemical Kinetic Studies Of The Halides And Halogens At A Platinum Rotating Ring-Disk Electrode In Anhydrous Acetic Acid, Donald Harrison Cranney Dec 1976

Voltammetric And Electrochemical Kinetic Studies Of The Halides And Halogens At A Platinum Rotating Ring-Disk Electrode In Anhydrous Acetic Acid, Donald Harrison Cranney

Theses and Dissertations

The electrochemical behavior of the iodine-iodide couple was investigated in both basic and neutral acetic acid solutions at a platinum rotating ring-disk electrode. Voltammetric curves were obtained and discussed. Various kinetic parameters were determined and by comparing to theoretical kinetic parameters a probable reaction mechanism was deduced. The mechanism that best fit experimental results is the following I- + S = I(S) + e- I(S) + I- = I2 + S + e (slow). The electrochemical behavior of bromine, bromide, and chloride was also investigated in the same media. Voltammetric curves were recorded and discussed with emphasis on the hysteresis …

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A Study Of Selected Photo Fries Rearrangements, Elwood Lloyd Loveridge Dec 1976

A Study Of Selected Photo Fries Rearrangements, Elwood Lloyd Loveridge

Theses and Dissertations

The Fries rearrangement of phenyl esters is reviewed and compared to the reaction when light is the source of energy. The products are different due to different mechanism of reaction. Light energy causes either free radical or concerted reactions. The S-phenylthiol esters and anilides were studied also. Although many of the rearrangements are the same, we did not see any alkyl migration nor decarboxylation type reactions with either the sulfur or nitrogen compounds. Three papers have been published from this work: Bradshaw, J. S., Knudsen, R. D. and Loveridge, E. L., J. Org. Chem., 35, 1219 (1970); Bradshaw, J. S., …

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The Effects Of Ultrasonic Vibration, Tension And Torsion On The Charge Acceptance Of The Alkaline Silver Electrode ; Ii. Potentiostatic Studies Of The Oxide Growth Rate Law For The Alkaline Silver Electrode ; Iii. The Determination Of Ionic Transport In Silver Oxide Using Radiotracer Techniques With Ag[Superscript 110m], Reed Harold Chase Dec 1976

The Effects Of Ultrasonic Vibration, Tension And Torsion On The Charge Acceptance Of The Alkaline Silver Electrode ; Ii. Potentiostatic Studies Of The Oxide Growth Rate Law For The Alkaline Silver Electrode ; Iii. The Determination Of Ionic Transport In Silver Oxide Using Radiotracer Techniques With Ag[Superscript 110m], Reed Harold Chase

Theses and Dissertations

The effect of ultrasonic vibration on the anodic oxidation of silver foil in KOH was studied. An increase in charging capacity of approximately 20% was found to be the result of cavitation erosion. Silver wire was exposed to tension and torsion during oxidation but no change in charge acceptance was caused by these stresses. The oxide growth rate on silver foil electrodes was compared to rate equations that have been proposed for other metals. Uhlig's equations for the growth of semiconductor oxides was found to describe most of the data. The data did not fit other rate equations. Determination of …

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Computer Model Of A Fast Toroidal Plasma Compression, With Application To The Topolotron, H. Mark Nelson, Keith H. Brown, Charles A. Hart Nov 1976

Computer Model Of A Fast Toroidal Plasma Compression, With Application To The Topolotron, H. Mark Nelson, Keith H. Brown, Charles A. Hart

Faculty Publications

The method is developed for a comuputer sequence which models a fast toroidal theta or screw pinch for a highly conducting axially symmetric plasma. The computer sequence takes into account the self-inductances of the plasma and the external conductors which drive the compression as well as the mutual inductance which electromagnetically couples the two. The computer sequence is divided into three phases: a snowplow compression phase, an adiabatic compression phase, and a crowbarred circuit phase. The computer sequence is applied to a topolotron and an example is given of a magnetohydrodynamic equilibrium geometry for which the plasma surface possesses an …

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Behavior Of A Manganin Coil At Elevated Temperatures And Pressures, Jonathan D. Weiss, Daniel L. Decker, H. B. Vanfleet Sep 1976

Behavior Of A Manganin Coil At Elevated Temperatures And Pressures, Jonathan D. Weiss, Daniel L. Decker, H. B. Vanfleet

Faculty Publications

We have determined the temperature dependence in the first-order pressure coefficient of a manganin coil to be dBetaB/dT= (4.2±0.8) ×10^-7 (kbar degrees C)^-1 in the equation R (T,P) =R (T,0)(1+BetaP+GammaP2), where R (T,P) is the coil resistance at temperature T and pressure P. The measurements were performed by simultaneously measuring the coil resistance and temperature at the transitions of mercury and bismuth, which were observed by differential thermal analysis.

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The Intermolecular Potential And Vibrational Relaxation Of The Ar-Co System, Gregory Allen Parker Aug 1976

The Intermolecular Potential And Vibrational Relaxation Of The Ar-Co System, Gregory Allen Parker

Theses and Dissertations

The angle, distance and vibration dependence of the Ar-CO intermolecular potential is calculated using the electron gas model to obtain the short range interaction which is smoothly joined onto the long range van der Waals tail which is obtained from accurate C_6, C_7, and C_8 coefficients. Our calculated second interaction virial coefficients are compared with experiment and with a simple adjustment of the Ar-CO potential an excellent agreement is obtained. Our spherically averaged potential is also in excellent agreement with a spherical potential inferred from high energy scattering data. Simplified expressions for the scattering amplitude and differential cross section are …

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Esr Study Of Free Radicals In Irradiated Single Crystals Of Potassium Hydroxylamine Disulfonate, B. J. Wilson, Robert W. Holmberg Aug 1976

Esr Study Of Free Radicals In Irradiated Single Crystals Of Potassium Hydroxylamine Disulfonate, B. J. Wilson, Robert W. Holmberg

Faculty Publications

Two free radicals formed when single crystals of potassium hydroxylamine disulfonate are irradiated with gamma rays at 77degrees K were studied by ESR. The ESR spectra result from a predominant center (radical A) exhibiting large 14N and 1H hyperfine splittings and from lesser amounts of Fremy's radical [O-dotN(SO3)2-2]. The g and hyperfine tensors of these radicals have been evaluated and are discussed. Radical A, whose identity remains in doubt, may be regarded as the precursor to Fremy's radical; on warming its lines decay and those of Fremy's radical are formed. Lines from radical A decrease in strength and those of …

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A Comparison Of Free Radical Detection Methods, Danny Kiang-Wah Pan Aug 1976

A Comparison Of Free Radical Detection Methods, Danny Kiang-Wah Pan

Theses and Dissertations

The methods used for free radical detection are chemical titration, spectrophotometry, Gouy magnetic measurements and NMR shift technique. The free radicals chosen for this study are Fremy' s salt (ON(SO_3 )K_2),2,2-diphenyl-1-picryl hydrazyl (DPPH) 3-carbamoyl-2,2,5,5-tetramethylpyrrolidin-1-yloxy (CTM-pyrrolidin), 3-carbamoyl-2,2,5,5-tetramethyl-3-pyrrolin-1-yloxy (CTM-pyrrolin), 4-acetamido-2,2,6,6-tetramethylpiperidino-1- oxyl (ATMP) and galvinoxyl. The detectable range for each method is given. The NMR method is a fast and convenient method for the magnetic susceptibility determination of a sample in solution, with. accuracy up to ± 1%.

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A Potentiometric Method, A Convenient And Rapid Technique For Determination Of The Thermodynamics Of Ionization Reactions For Water, Weak Acids, And Some Slightly Soluble Salts In Aqueous Organic Mixed Solvents, Charanai Panichajakul Aug 1976

A Potentiometric Method, A Convenient And Rapid Technique For Determination Of The Thermodynamics Of Ionization Reactions For Water, Weak Acids, And Some Slightly Soluble Salts In Aqueous Organic Mixed Solvents, Charanai Panichajakul

Theses and Dissertations

A potentiometric method which is devised to be rapid and convenient for determining ionization constants for water, weak acids (or bases), and certain solids in mixed solvents is described. The method has been applied to the determination of ionization for water, acetic acid, benzoic acid, and phenol and the solubility product constant for silver chloride in mixtures of water with methanol, ethanol, acetone, tetrahydrofuran, and p-dioxane containing from 0 to 70 mass percent organic co-solvent at several temperatures between 10 and 40°C. Results are used to study the thermodynamics of ionization in each mixture which is discussed relative to various …

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Solid-Liquid Phase Equilibria In Systems Of (I) Para-Xylene, (Ii) Mesitylene, And (Iii) N,N-Dimethylformamide ; Excess Volume Determination In Systems Containing Cyclohexane ; Calculations Of Activities For The N-Hexane + Cyclohexane System, John F. Moellmer Jul 1976

Solid-Liquid Phase Equilibria In Systems Of (I) Para-Xylene, (Ii) Mesitylene, And (Iii) N,N-Dimethylformamide ; Excess Volume Determination In Systems Containing Cyclohexane ; Calculations Of Activities For The N-Hexane + Cyclohexane System, John F. Moellmer

Theses and Dissertations

Solid-liquid phase equilibria studies were used to investigate possible compolllld formation in solutions of (i) para-xylene, (ii) mesitylene, and (iii) N,N-dimethyl-formamide (DMF) with mono- and di- halobenzenes that were selected to give a wide range of acceptor properties. Solid 1:1 intermolecular compounds were identified from solutions of p-C_6H_4F_2 with mesitylene, p-C_6H_4Br_2 with p-xylene, and p-C_6H_4Cl_2 with p-xylene. The results suggest that compound formation occurs because of favorable geometry rather than a charge transfer process. A vibrating tube densimeter was used to determine, with high precision, the densities and subsequently excess volumes of mixing of the n-hexane plus cyclohexane system. Temperature …

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The Synthesis Of Analogs Of Toxoflavin And Fervenulin As Potential Antimetabolites, Bernadette Kuo Billings Apr 1976

The Synthesis Of Analogs Of Toxoflavin And Fervenulin As Potential Antimetabolites, Bernadette Kuo Billings

Theses and Dissertations

The synthesis of analogs of toxoflavin: 1,3,4,6-tetramethyl-1,5,6, 7-tetrahydropyrimido[4,5-c]-5,7-pyridazinedione; 1,6-dimethyl-3,4-diphenyl-1,5,6,7-tetrahydropyrimido[4,5-c]-5,7-pyridazinedione; 3,5,7-trimethyl-8-phenyl-2,3,4,8-tetrahydropyrido[2,3-d]-2,4-pyrimidinedione are discussed. The synthesis of analogs of fervenulin: 3,4,6-trimethyl-5,6,7,8-tetrahydropyrimido[4,5-c]-5,7-pyridazinedione; 6-methyl-3,4-diphenyl-5,6,7,8-tetrahydropyrimido[4,5-c]-5,7-pyridazinedione; 2-hydroxy-3,5,7-trimethyl-4(3H)pyrido[2,3-d]-2,4-pyrimidinone are discussed. Several intermediates have been prepared: 6 -methylamino-3-methyluracil by a new method; 6-n-propylamino-3-methyluracil: 6-n-butylamino-3-methyluracil and 3-ethyl-2-ethylthio-2-hydroxy-4(3H)pyrimidinone.

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Hard And Soft Nucleophilic Substitution Patterns In Amino-Methylsulfonylazines, Calvin Wilson Mccausland Mar 1976

Hard And Soft Nucleophilic Substitution Patterns In Amino-Methylsulfonylazines, Calvin Wilson Mccausland

Theses and Dissertations

The selectivity observed with 2,4,7-triamino-6-methylsulfonyl-pteridine when reacted with "hard" aliphatic amines and "soft" aryl-thiols resulting in amine exchange at the 2-, 4-, and 7-positions and displacement of the 6-methylsulfonyl moiety, respectively, was further investigated in other ring systems. The substrates tested were disubstituted with amino- and methylsulfonyl- moieties, and included the benzene, pyridine, pyrazine, quinoxaline, quinazoline and pteridine ring systems. The methylsulfonyl moiety is preferentially displaced by both thiols and amines with quinoxaline and quinazoline substrates, and is more reactive towards displacement by thiol than amine nucleophiles. Amine exchange occurs with the quinoxaline substrate subsequent to displacement of the methylsulfonyl …

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Van Der Waals Interactions Of Carbon Monoxide, Gregory A. Parker, Russell T. Pack Mar 1976

Van Der Waals Interactions Of Carbon Monoxide, Gregory A. Parker, Russell T. Pack

Faculty Publications

Pade approximant methods and experimental frequency dependent polarizabilities are used to calculate reliable van der Waals C6 coefficients for the interaction of CO with He, Ne, Ar, Kr, Xe, H, Li, Na, K, Rb, Cs, H2, N2, O2, CO2, and CO. Error bounds are given for the C6 coefficients and for the CO oscillator strength sums.

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Van Der Waals Interactions Of Ii-State Linear Molecules With Atoms. C6 For No(X 2Π) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack Mar 1976

Van Der Waals Interactions Of Ii-State Linear Molecules With Atoms. C6 For No(X 2Π) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack

Faculty Publications

Formulas are derived for the van der Waals Cn coefficients for the interaction of a diatomic molecule in a II electronic state with an S-state atom. Two triatomic states arise from the degenerate IIstate. The average of the two energies has the usual Legendre polynomial (PL) angular dependence, but the difference in energies of the two states is shown to have associated Legendre polynomial (PML with M=2) angular dependence. Procedures for including spin orbit coupling are included, and the extension to interactions of Delta- and Phi-state molecules is discussed. Values of the spherical part of the C6 coefficients for the …

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Comment On ''Inelastic Scattering In Atom-Diatomic Molecule Collisions. I. Rotational Transitions In The Sudden Approximation'', Russell T. Pack Feb 1976

Comment On ''Inelastic Scattering In Atom-Diatomic Molecule Collisions. I. Rotational Transitions In The Sudden Approximation'', Russell T. Pack

Faculty Publications

It is argued that conflicting approximations in a recent paper [J. R. Stallcop, J. Chem. Phys. 61, 5085 (1974)] render the resulting theory invalid.

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Calorimetric Determination Of The Interaction Of Cu, Fe, And V Oxides With So₂ And Measurement Of Sulfur (Iv) And Sulfur (Vi) In Particulate Samples From Utah Valley, Douglas F. Cannon Dec 1975

Calorimetric Determination Of The Interaction Of Cu, Fe, And V Oxides With So₂ And Measurement Of Sulfur (Iv) And Sulfur (Vi) In Particulate Samples From Utah Valley, Douglas F. Cannon

Theses and Dissertations

The adsorption of SO2 by metal oxides suspended in decane were studied by calorimetric titration. The adsorption per surface area decreases in order CuO > Cu2O > Fe2O3 > V2O5. An Andersen High Volume sampler was used to obtain particulate samples from five sites in Utah County. Particulate sulfur (IV) and sulfur (VI) was analyzed by thermometric titration with K2Cr2O7 and by a direct injection enthalpimetric determination using BaCl2. Results show that little oxidation of the S(IV) occurs after it is released from the Kennecott smelter stack.

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Studies Of N⁵, N¹⁰-Methylene Tetrahydrofolate Reductase From Porcine Kidney And Mouse L1210-Induced Tumor Tissues, Purification And Interaction With Antifolates, David W. Jayme Dec 1975

Studies Of N⁵, N¹⁰-Methylene Tetrahydrofolate Reductase From Porcine Kidney And Mouse L1210-Induced Tumor Tissues, Purification And Interaction With Antifolates, David W. Jayme

Theses and Dissertations

Methylene tetrahydrofolate reductase has been purified 1000-fold from porcine kidney and 400-fold from mouse L1210-induced tumor tissue by classical methods. The enzyme preparations have been demonstrated to be essentially free of contaminating methionine synthetase and serine transhydroxymethylase activity. Studies of the kinetic properties of the kidney and tumor enzymes, with respect to the reverse reaction using N5-methyl tetrahydrofolate as the variable substrate, have indicated Km values of 2.0 and 2.4 x 10-4 M, respectively. Inhibition of this key branch point enzyme in folate metabolism by a number of antimetabolites indicates that several of these antifolate compounds exhibit enzyme inhibition superior …

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The Effect Of Nitroalkanes On The Electrolytic Oxidation Of Tertiary Butyl Amine And Tertiary Amyl Amine, Karl Lloyd Bergen Aug 1975

The Effect Of Nitroalkanes On The Electrolytic Oxidation Of Tertiary Butyl Amine And Tertiary Amyl Amine, Karl Lloyd Bergen

Theses and Dissertations

The electrolyses of tert.-butyl and tert.-amyl amines were run with a voltage of approximately 3v., as measured across the cell, with and without the presence of 1-2% nitro-tert.-alkane. A graphite anode was used; the supporting electrolyte was NaClO4; the solvent was the reacting amine(s) with 10-20% water to solubilize the NaClO4. The products were azo compounds, azoxy compounds, 1,3-disubstituted ureas and traces of nitroso compounds. In the case of tert.-butyl amine di-tert.-butyl carbodiimide was also shown to be a product. The presence of nitro compounds increased the yields of azoxy and nitroso compounds and decreased the yields of azo compounds. …

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Synthesis And Stereochemistry Of 2,6,10-Triazatricyclo [5.2.1.0⁴ ¹⁰] Decane Derivatives, Susan Elaine Foulger Aug 1975

Synthesis And Stereochemistry Of 2,6,10-Triazatricyclo [5.2.1.0⁴ ¹⁰] Decane Derivatives, Susan Elaine Foulger

Theses and Dissertations

The synthesis and stereochemical aspects of derivatives of the new ring system 2,6,10-triazatricyclo [5.2.1.04,10] decane are discussed. Sythesis of 2-nitro-2-methyl-1,3-disubstitutedaminopropanes, followed by reduction of these compounds to 2-amino-2-methyl-1,3-disubstituted aminopropanes afforded the necessary starting materials for a cyclization reaction similar to that resulting in already known 2,6-dioxa-10-azatricyclo [5.2.1.04,10] decanes. Reaction of the triamines with 2,5-hexanedione resulted in 2,6-disubstituted-1,4,7-trimethyl-2,6,10-triazatricyclo [5.2.1.04,10] decanes. The stereochemical aspects of this ring system are interesting from the standpoint of nitrogen inversion barriers on nitrogens 2 and 6. Existence of a high inversion barrier for these nitrogens in shown by isolation of different diastereomers of the tricycle. Methods …

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Macrocyclic Polyether Sulfide Syntheses :|Bthe Preparation Of Thia-Crown-6, 7, And 8 Compounds, Robert Askew Reeder Aug 1975

Macrocyclic Polyether Sulfide Syntheses :|Bthe Preparation Of Thia-Crown-6, 7, And 8 Compounds, Robert Askew Reeder

Theses and Dissertations

Macrocyclic polyether sulfides have been prepared by reacting an oligoethylene glycol dichloride with a dithiol in refluxing basic ethanol. The following new compounds were prepared: 1,5-dithia-(19- crown-6), 3-hydroxy-1,5-dithia-(19-crown-6), 1,4-dithia-(21-crown-7), 3-hydroxy-1,5-dithia-(22-crown-7), and 1,4-dithia-(24-crown-8). One other previously reported macrocyclic polyether sulfide was also prepared. The thesis includes a review of macrocyclic sulfides and other related compounds, the thermodynamics of interaction of several macrocyclic polyether sulfides with Ag^+, Hg^2+, and Pb^2+ ions, and a discussion of the structure of these materials.

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The Effect Of Recreational Uses On Vegetation And Soil In The Buffalo Campground, Targhee National Forest, Island Park, Idaho, Susan Daines Foster Aug 1975

The Effect Of Recreational Uses On Vegetation And Soil In The Buffalo Campground, Targhee National Forest, Island Park, Idaho, Susan Daines Foster

Theses and Dissertations

The effect of trampling on vegetation and soil, as a result of recreational pressure, was studied in the Buffalo campground of the Targhee National Forest, Idaho. Site deterioration was most evident in the forty-two year old site. The tree stand had matured, but there were few young trees and tree reproduction had been reduced to ten seedlings per acre for Pinus contorta. Only two shrub species were sampled with a combined population of eight individuals per acre. Most of the grass species had been seeded; forbs provided 20% of the ground cover, 13% was bare ground and 71% litter. The …

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Close Coupling Test Of Classical And Semiclassical Cross Sections For Rotationally Inelastic Ar-N2 Collisions, Russell T. Pack Apr 1975

Close Coupling Test Of Classical And Semiclassical Cross Sections For Rotationally Inelastic Ar-N2 Collisions, Russell T. Pack

Faculty Publications

Accurate quantum mechanical close coupling (CC) integral cross sections are reported for rotationally inelastic Ar-N2 collisions at room temperature using an empirical intermolecular potential. These cross sections are used to test the infinite order sudden (IOS) approximation and the results of several methods [classical trajectories (CT), full sudden (SA), generalized phase shift (GPS), and classical limit generalized phase shift (CGPS)] as reported in the preceding paper by Pattengill. The IOS approximation works very well for cross sections involving low rotational states. The CT method works well for all the cross sections examined, justifying the popular belief that the rotational motion …

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Development Of Proton-Induced X-Ray Emission Techniques With Application To Multielement Analyses Of Human Autopsy Tissues And Obsidian Artifacts, Kirk Kay Nielson Apr 1975

Development Of Proton-Induced X-Ray Emission Techniques With Application To Multielement Analyses Of Human Autopsy Tissues And Obsidian Artifacts, Kirk Kay Nielson

Theses and Dissertations

A method of trace element analysis using proton-induced X-ray emission (PIXE) techniques with energy dispersive X-ray detection methods is described. Data were processed using the computer program ANALEX. PIXE analysis methods were applied to the analysis of liver, spleen, aorta, kidney medulla, kidney cortex, abdominal fat, pancreas and hair from autopsies of Pima Indians. Tissues were freeze dried and low temperature ashed before analysis. Concentrations were tabulated for K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Pb, Se, Br, Rb, Sr, Cd and Cs and examined for significant differences related to diabetes. Concentrations of Ca and Sr in aorta, …

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A Comparative Investigation Of Mammalian Serine Transhydroxymethylases, Sanha Panichajakul Apr 1975

A Comparative Investigation Of Mammalian Serine Transhydroxymethylases, Sanha Panichajakul

Theses and Dissertations

Serine transhydroxymethylase was purified one thousand-fold from bovine brain and one hundred and twenty-fold from bovine liver. Both enzymes were yellow due to the presence of the coenzyme pyridoxal 5'-phosphate. Polyacrylamide gel electrophoresis of the liver enzyme showed one major band containing 95% of the protein, while in the case of the brain enzyme two major bands of nearly equal intensity were observable. The specific activity of the crude liver enzyme was about sixty times higher than that of brain. The liver enzyme was also more heat stable than the brain enzyme. The purified enzymes exhibited L-allothreonine and L-threonine aldolase …

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Composition, Time, And Size Distributions Of Airborne Particulate Material In Utah Valley, Douglas R. Lawson Apr 1975

Composition, Time, And Size Distributions Of Airborne Particulate Material In Utah Valley, Douglas R. Lawson

Theses and Dissertations

The Lundgren impactor is used to determine the variations in time and size distributions of particulate matter in Utah Valley. Charged particle X-ray fluorescence is employed in this study to determine elemental concentrations. Air samples are taken during two 24-hour periods in downtown Provo, 24 hours near U.S. Steel Corporation, Geneva Works, and 12 hours at Lindon Elementary School, and diurnal particulate variations are compared. The amounts of lead and bromine are four times greater on a weekday than on a Sunday in downtown Provo, suggesting the effect of the automobile on atmospheric particulate concentrations. Paraffin coated impaction surfaces are …

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The Kinetics And Mechanism Of A Free Radical Decay In Aqueous Solution, Denzel Lee Fillmore Apr 1975

The Kinetics And Mechanism Of A Free Radical Decay In Aqueous Solution, Denzel Lee Fillmore

Theses and Dissertations

The decomposition of nitrosyl disulfonate ion was studied in strongly alkaline solution of 10-2 to 5 m sodium hydroxide. The decomposition was found to be first-order in both hydroxide and nitrosyl disulfonate ions. A multi-step mechanism involving sulfite ion, sulfite ion radical and nitrosyl monosulfonate ion radical as intermediates was proposed, with the initiating step being the SN2 replacement of a sulfite ion by a hydroxide ion. The rate constant for the initiating step ranged from 1.2 x 10-7 to 2.25 x 10-5 M-1s-1 for the solution concentration range of the study. The products of the decomposition were identified as …

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