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Articles 2761 - 2790 of 2906

Full-Text Articles in Physical Sciences and Mathematics

X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve Ii. Sodium, Keith H. Brown, J. Dean Barnett Sep 1972

X-Ray Diffraction Studies On Liquids At Very High Pressures Along The Melting Curve Ii. Sodium, Keith H. Brown, J. Dean Barnett

Faculty Publications

Coherent x-ray diffraction patterns for liquid Na have been extracted from measured patterns at 0.5, 7.5, 17, and 43 kbar along the melting curve. The experimentally determined liquid structure factor and resulting radial distribution function are given at each pressure. The position of the principal x-ray intensity peak is reproducible to within 0.5% and shows shifts of the order of 12%. The resulting nearest neighbor distance in the radial distribution function also shifts 12% but is reproducible only to approximately 2%. The distribution functions obtained at points along the melting curve suggest a simple dimensional compression or scaling; however, a …

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Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Bronwyn Geraldine Hughes Jul 1972

Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Bronwyn Geraldine Hughes

Theses and Dissertations

A possible method for the synthesis of ordered oligoribonucleotides involves primer-dependent polynucleotide phosphorylase (PNPase) synthesis using the RNase A or T1 resistant N-cyclohexyl-N'-β(4-methylmorpholinium)ethylcarbodiimide chloride (CMC-Cl) derivatives of uridine or guanosine containing primers. Thus, CMC-UpA, CMC-GpA, CMC-UpCpC, CMC-GpApC, and ApApApApU-CMC were prepared and studied as primers for PNPase in 15 min 14C-ADP polymerization reactions and also in 6-10 hr synthesis reactions. The CMC-primers were not suitable primers for PNPase catalyzed synthesis reactions for either time. The PNPases used in such studies were contaminated with nuclease that showed the following order of susceptibility: UpA > CpC, GpA > ApU, ApA. Even a highly purified …

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Β-Delayed Proton Decay Of 9c, David D. Allred, John E. Esterl, J. C. Hardy, R. G. Sextro, Joseph Cerny Jul 1972

Β-Delayed Proton Decay Of 9c, David D. Allred, John E. Esterl, J. C. Hardy, R. G. Sextro, Joseph Cerny

Faculty Publications

The delayed-proton spectrum following the β decay of 9C (t1/2=126.5±1.0 msec) was found to consist primarily of a continuum extending from 13 to 1.5 MeV, the latter being the lowest energy observed. In addition to the previously observed peaks at 9.28 and 12.30 MeV (C.M.), possible peaks between 3 and 7 MeV have been tentatively identified.

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Synthesis And Metal Coordination Properties Of Some Cyclic Polyethers And Polythioethers, Barry Lant Haymore May 1972

Synthesis And Metal Coordination Properties Of Some Cyclic Polyethers And Polythioethers, Barry Lant Haymore

Theses and Dissertations

Thermodynamic values for cation-cyclic polyether interactions for several systems are reported and discussed in light of ligand geometry, cation selectivity, solvent effects, structure, stoichiometry and the nature of the coordinate bond. Cyclic polyethers are shown to be remarkably good ligands even in water and to have marked selectivity for d0, d10 and d10 s2 cations. Syntheses of one new cyclic polyether and several new mixed cyclic polyether-thioethers are reported. Cyclic chelates with smaller rings are shown to prefer smaller cations, but this selectivity is masked by the hydration energy of the cation. Except for thiophillic cations such as Hg2+ and …

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Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Mark J. Rowe May 1972

Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Mark J. Rowe

Theses and Dissertations

The synthetic reaction of ribonuclease T_1 has been studied as to its potential for the synthesis of oligoribonucleotides of defined base sequence. Conditions have been determined for maximum synthesis with respect to percentage incorporation of both guanosine 2',3'-cyclic phosphate (donor), and cytidine (acceptor). With regard to maximum acceptor incorporation, a donor blocked at the 5'-hydroxyl has been used to drive the reaction. It has also been shown that acceptor incorporation decreases as the chain-length increases up to the hexanucleotide. Synthesis of a 3'-blocked substrate for polynucleotide phosphorylase for use in chain termination studies was attempted using adenylate kinase. In this …

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A New Method For The Preparation Of Alkylnaphthyl Ethers And Sulfides, Edward Ying-Shih Chen May 1972

A New Method For The Preparation Of Alkylnaphthyl Ethers And Sulfides, Edward Ying-Shih Chen

Theses and Dissertations

The reaction of monohalonaphthalenes with metal alkoxides and mercaptides in a solvent mixture of the corresponding alcohol and dimethyl sulfoxide (DMSO) has been studied. These reactions are convenient methods for the preparation of alkylnaphthyl ethers and sulfides. Only direct nucleophilic substitution was observed in the reactions of bromonaphthalenes with sodium methoxide and sodium nbutyl mercaptide. The reaction of fluoronaphthalene with potassium t-butoxide also proceeded by way of direct nucleophilic substitution rather than the 1,2-dehydronaphthalene intermediate as in the reactions of bromonaphthalene with potassium t-butoxide. The use of a base which is weaker than t-butoxide can change the apparent reaction mechanism …

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Electrolytic Synthesis Of [Gamma]-Diketones, Leon F. Pahler May 1972

Electrolytic Synthesis Of [Gamma]-Diketones, Leon F. Pahler

Theses and Dissertations

Four γ-diketones were synthesized by using a modification of the Kolbe electrolytic condensation of β-ketocarboxylic acids. [--see equation in thesis--] The following γ-diketones were synthesized in moderate yields: 2,5-hexanedione, 4,7-decanedione, 2,2,7,7-tetramethyl- 3,6-octanedione, and 1,4-diphenyl-1,4-butanedione (34, 39, 23, and 27, respectively). However, attempted preparation of the following γ-diketones failed: 3,4-dimethyl- 2,5-hexanedione, 3,3,4,4-tetramethyl-2,5-hexanedione, and 1,4-di(2-thienyl)-1,4-butanedione. Attempts to electrolytically condense α-alkyl and α, α-dialkyl substituted monocarboxylic acids have been reported and all attempts have ended in failure; similarly, the attempts to synthesize 3,4-dimethyl and 3,3,4,4-tetramethyl- 2,5-hexanedione from 2-methyl and 2,2-dimethyl-3- oxobutanoic acid, respectively, failed. The preparation of 1,4-di(2-thienyl)-l,4-butanedione failed because the product or …

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Rhenium Catalyzed Hydrogenation Of Maleic Anhydride And Crotonaldehyde, William Russel Dixon May 1972

Rhenium Catalyzed Hydrogenation Of Maleic Anhydride And Crotonaldehyde, William Russel Dixon

Theses and Dissertations

The preparation of a number of supported rhenium catalysts is reported. The determination of their activity and selectivity and of optimal reaction parameters for the reduction of maleic anhydride and crotonaldehyde is reported. Optimal time of hydrogenation was chosen as one hour and pressures were chosen as 2000 psig for crotonaldehyde and 3000 psig for maleic anhydride. Quantitative reduction of maleic anhydride to tetrahydrofuran occurred at 275° with charcoal supported rhenium catalysts. Lower temperatures (ca. 200°) produce quantitative amounts of butyrolactone. Unsupported catalysts at low temperatures (100°) selectively reduce crotonaldehyde to crotyl alcohol, but at very low conversion rates. Temperatures …

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Toward Hydrogen Bonds Of Predictable Geometry, Robert Shao-Chih Hsu May 1972

Toward Hydrogen Bonds Of Predictable Geometry, Robert Shao-Chih Hsu

Theses and Dissertations

A literature review on the geometry of hydrogen bonding showed that the geometry is often de-emphasized or even ignored, probably because of the inherent flexibility of many systems studied. Examination of molecular models suggested the geometrically constrained bicyclo [2, 2, 1] heptane system wherein hydrogen bond distances and angles might be more easily predicted. Dihydroboration-oxidation of norbornadiene was shown to yield exo, exo-2,5-norbornadiol, thus clarifying uncertainties in the literature. 2, 5-Norbornadiol was oxidized to the corresponding dione, heretofore inadequately characterized. Several derivatives of the dione were prepared, and spectral data were accumulated for the dione, its precursor, and its derivatives. …

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On The Mechanism Of Low-Temperature Termolecular Atomic Recombination, Russell T. Pack, Richard L. Snow, Wesley D. Smith Jan 1972

On The Mechanism Of Low-Temperature Termolecular Atomic Recombination, Russell T. Pack, Richard L. Snow, Wesley D. Smith

Faculty Publications

A simple theory of gas-phase termolecular atomic recombination kinetics is presented which treats the bound-complex (BC) mechanism in a fashion which parallels the Roberts, Bernstein, and Curtiss resonance theory of the energy-transfer (ET) mechanism. The ET rate constant has a low temperature maximum, but the BC rate constant does not. The contributions of the two mechanisms to the low-temperature recombination of hydrogen atoms, with He, Ar, and H2 as third bodies, are estimated and compared. The presence (absence) of a low-temperature maximum in the observable total rate constant is determined by absence (presence) of bound vibrational levels of the hydrogen-third …

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An Investigation Of Some Free Radicals.|Ni.|Pdecomposition Of Nitrosyl Disulfonate Ion In Polar Non-Aqueous Solvents.|Nii.|Preaction Between 2,2-Diphenyl -1- Picryl Hydrazyl And Nitrosyl Disulfonate Ion Free Radicals, Janan Mary Hayes Aug 1971

An Investigation Of Some Free Radicals.|Ni.|Pdecomposition Of Nitrosyl Disulfonate Ion In Polar Non-Aqueous Solvents.|Nii.|Preaction Between 2,2-Diphenyl -1- Picryl Hydrazyl And Nitrosyl Disulfonate Ion Free Radicals, Janan Mary Hayes

Theses and Dissertations

Part I reports the stud y of the decomposition of nitrosyl disulfonate ion in DMSO, acetonitrile, and dichloromethane. A multi-step mechanism involving sulfite ion, sulfite ion radical, and nitrosyl monosulfonate radical as intermediates is proposed. The products of the decomposition are nitrosonium ion, hydroxylamine disulfonate ion, and hydroxylamine trisulfonate ion. A competitive chain reaction was observed when the decomposition occurred in DMSO. The chain reaction was insignificant in carefully dried acetonitrile and dichloromethane. Part II reports the study of the reaction between 2,2-diphenyl-1-picryl hydrazyl (DPPH) and nitrosyl disulfonate ion. Product analysis and kinetic data obtained from stopped-flow procedures suggest that …

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Studies Of Pig Brain Thiamin Pyrophosphokinase, James Weldon Peterson Aug 1971

Studies Of Pig Brain Thiamin Pyrophosphokinase, James Weldon Peterson

Theses and Dissertations

Pig brain thiamin pyrophosphokinase (TPK) (ATP: thiamin pyrophosphotransferase, EC 2.7.6.2) was purified 260-fold over extracts of brain acetone powder. The purification was followed using a direct, radiometric assay. As determined in an analytical ultracentrifuge and by disc-gel electrophoresis, the most highly purified enzyme preparations were not homogeneous. The purified enzyme has a broad pH optimum extending from 8.3 to 9.3 in phosphate-glycylglycine buffer. It has an isoelectric point at about pH 4.2. For optimal enzymatic activity, the ratio of magnesium to ATP must be 0.6. Any deviation from this ratio causes a rapid drop in enzymatic activity. A study of …

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The Thermal Decomposition Of 2,2'-Azoisobutane, Mervin Dewain Atwood Aug 1971

The Thermal Decomposition Of 2,2'-Azoisobutane, Mervin Dewain Atwood

Theses and Dissertations

Nitrogen, isobutane, isobutylene and 2,2,3,3-tetramethylbutane are the only products found in the thermal decomposition of 2,2'-azoisobutane. They are the results of the direct free radical dimerization and disproportionation. Ratio of the rate constants of disproportionation to dimerization was found to be 1.9 at 268°C and 4.5% azobutane in helium. This compared with Blackham and Eatough's value of 1.4 at 243°C and 3.6 at 290°C with 4% azobutane in helium. The ratio of the disproportionation to dimerization increased with an increase in temperature. A change in contact time affected the ratio at lower reaction temperatures but had little effect on it …

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High-Pressure Equation Of State For Nacl, Kcl, And Cscl, Daniel L. Decker Jul 1971

High-Pressure Equation Of State For Nacl, Kcl, And Cscl, Daniel L. Decker

Faculty Publications

A calculation of the equation of state for NaCl from a Mie-Grüneisen equation was repeated using more accurate values of the zero-pressure compressibility. It was also extended to KCl and CsCl. An analysis of this approach to pressure calibration indicates that it will yield pressures with about the same accuracy as can be presently achieved by experimental measurements above 25 kbar, and thus furnishes a temporary practical pressure scale.

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Eutrophication Of Small Lakes, Lynn T. Kenison May 1971

Eutrophication Of Small Lakes, Lynn T. Kenison

Theses and Dissertations

An estimate was made to determine the amount of nitrate and phosphate entering Utah Lake in 1968. To make this estimate, the flow data for 1968 and the nitrate and phosphate concentrations for 1970 were used. This was done because of the lack of information. The results show that the total nitrate added to Utah Lake in 1968 was 7,638,000 pounds. The total phosphate added was 1,740,200 pounds. Of this amount, 12,4 per cent of the nitrate and 18.0 per cent of the phosphate was released from the lake through the Jordan River. The rest remained in the lake to …

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Solid-Liquid Phase Equilibria Studies :|Bi. Several Charge Transfer Systems ; Ii. A Metallic System ; Iii. A Liquid Crystal, Dee Edward Oyler May 1971

Solid-Liquid Phase Equilibria Studies :|Bi. Several Charge Transfer Systems ; Ii. A Metallic System ; Iii. A Liquid Crystal, Dee Edward Oyler

Theses and Dissertations

Solid-liquid phase equilibria studies were used to investigate possible compound formation in solutions of (i) N,N-dimethylformamide (DMF) and (ii) N,N-dimethylacetamide (DMA) with a series of halogenated hydrocarbons that were selected to give a wide range of acceptor properties. Solid 1:1 intermolecular compounds were identified from solutions of (i) DMF and (ii) DMA with CCl_4, CBrCl_3, and C_6H_5CCl_3. The intermolecular compounds (DMF)_2•CCl_4 and (DMF)_2•CBrCl_3 were also found. The results suggest charge transfer from DMF or DMA to the chlorine atoms of the acceptor molecule as the process for compound formation. Thermal methods were used to determine with high precision the solid-liquid …

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A Calorimetric Study Of Metal Ion Cyclic Polyether Interaction :|Bi. Cation Binding Properties Of Macrocyclic Polyethers In Aqueous Solution As A Function Of Temperature ; Ii. Effect Of Solvent Dielectric Constant On The Binding Properties Of Cyclic Polyethers For Na[Superscript +] And K[Superscript +], Dennis Pershing Nelson May 1971

A Calorimetric Study Of Metal Ion Cyclic Polyether Interaction :|Bi. Cation Binding Properties Of Macrocyclic Polyethers In Aqueous Solution As A Function Of Temperature ; Ii. Effect Of Solvent Dielectric Constant On The Binding Properties Of Cyclic Polyethers For Na[Superscript +] And K[Superscript +], Dennis Pershing Nelson

Theses and Dissertations

The complexation properties of the two isomers of the cyclic polyether dicyclohexyl-18-crown-6 are examined in aqueous solution for a series of metal ions at various reaction temperatures. The results are discussed in terms of size relationships and salvation characteristics of both polyether and metal ions. ΔCp° values are determined from the temperature dependence of the ΔH° values. A discussion of the errors involved in the determination of ΔH° from the temperature dependence of log K values is also included. Comparisons are made between the results of this study and those of a similar study by H. K. Frensdorff, E. I. …

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The Roles Of Chlorine Azide In Chemical Lasers, Walter Wood Rice May 1971

The Roles Of Chlorine Azide In Chemical Lasers, Walter Wood Rice

Theses and Dissertations

ClN_3 was photolyzed in various gas mixtures to transform its chemical energy into laser radiation. Reaction mechanisms, energy distribution in reaction products, and relative reaction rates were deduced from the laser emission. Flash photolysis of ClN_3-H_2 mixtures produced HCl laser emission; however, due to a narrow range of operating conditions and many competing reactions, the laser output was less than that obtained from comparable Cl_2-H_2 mixtures. The rate constants for H + ClN_3 —> HCl* (v=n) + N_3 were determined to be 0.45 ± 0.05 of the corresponding rate constants for H + Cl_2 —> HCl* (v=n) + Cl. Chlorine …

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Solid-Liquid Phase Equilibria Of The Potassium-Rubidium And Rubidium-Cesium Alloy Systems, Elisabeth M. Delawarde May 1971

Solid-Liquid Phase Equilibria Of The Potassium-Rubidium And Rubidium-Cesium Alloy Systems, Elisabeth M. Delawarde

Theses and Dissertations

Thermal methods of high precision were used to determine the solid-liquid phase equilibria diagrams for the potassium-rubidium and the rubidium-cesium systems. Both form minima in the liquidus curves occurring at 307.00° K with 0.667 mole fraction rubidium in the potassium-rubidium system and 282.85° K with 0.530 mole fraction cesium in the rubidium-cesium system. In the potassium-rubidium system, the liquidus and solidus points are very close together, giving a very narrow temperature range for the two phase region. The freezing point minimum in the potassium-rubidium system occurs at 0.667 mole fraction rubidium, suggesting the possible formation of a KRb2 intermetallic compound.

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Lamb-Mössbauer Factor Of Sodium Ferrocyanide, Daniel L. Decker, L. E. Lortz Feb 1971

Lamb-Mössbauer Factor Of Sodium Ferrocyanide, Daniel L. Decker, L. E. Lortz

Faculty Publications

Using a set of commercially prepared sodium ferrocyanide absorbers enriched to 91.2% Fe57 the Lamb-Mössbauer factor was measured to be 0.28±0.03. The thickness of Fe57 for these absorbers was measured using x-ray absorption techniques and was found to be considerably smaller than that advertised by the manufacturer even after correcting for the size of the ferrocyanide particles in the absorbers.

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Attitudes Concerning Birth Control And Abortion As Related To Lds Religiosity Of Brigham Young University Students, Erlend D. Peterson Jan 1971

Attitudes Concerning Birth Control And Abortion As Related To Lds Religiosity Of Brigham Young University Students, Erlend D. Peterson

Theses and Dissertations

This study was an analysis of the relationship between LDS religiosity of college students and their attitudes concerning birth control and abortion.

The respondents in this research were LDS college students attending Brigham Young University Fall Semester 1970. Goodman and Kruskal's gamma and a difference of means test were used to measure association and difference to determine the statistical significance of the responses as related to religiosity and attitudes concerning birth control and abortion.

The results of the study showed that (1) there was a positive relationship between conservative attitudes toward birth control and abortion and one's degree of measured …

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High-Pressure Phase Studies On Sodium–Potassium Alloys, D. Ray Anderson, J. Bevan Ott, Rex J. Goates, H. Tracy Hall Jan 1971

High-Pressure Phase Studies On Sodium–Potassium Alloys, D. Ray Anderson, J. Bevan Ott, Rex J. Goates, H. Tracy Hall

Faculty Publications

The solid–liquid phase diagrams were investigated to 60 kbar for elemental sodium, potassium, and various sodium–potassium alloys. The data for Na and K are in general agreement with those of earlier workers. In the alloy system the temperatures of both the peritectic and eutectic halts increase as the pressure increases, but with different slopes, so that the two invariant points merge at approximately 35 kbar. Above this pressure, two halts are again observed. One increases with increasing pressure, and the other decreases with increasing pressure up to 55 kbar, where it abruptly starts increasing again. Melting points for samples in …

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The Effects Of Various Treatments On Thiamin Diphosphate And Total Thiamin Levels Of Rat Tissues, Dong Hwa Park Aug 1970

The Effects Of Various Treatments On Thiamin Diphosphate And Total Thiamin Levels Of Rat Tissues, Dong Hwa Park

Theses and Dissertations

Tissue thiamin diphosphate was assayed enzymatically utilizing purified brewer's yeast apotransketolase. With this assay ten uumoles of thiamin diphosphate could be detected. Total thiamin was fluorometrically measured. For one to three days rats were placed under conditions of stress, consisting of loud noise treatment, emotional stress, deprivation of paradoxical sleep, and swimming to exhaustion, respectively. The body weight was markedly decreased at the end of the respective experimental periods except with the loud noise treated group, compared with the corresponding controls. Following two to three such consecutive treatments, the adrenal weight also showed a significant increase. Thiamin diphosphate and total …

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The Chemistry Of Dehydronaphthalene, Richard Harold Hales Aug 1970

The Chemistry Of Dehydronaphthalene, Richard Harold Hales

Theses and Dissertations

The reaction of monohalonaphthalenes with potassium t-butoxide in a t-butyl alcohol-dimethyl sulfoxide (DMSO) mixture has been studied. The 1-bromonaphthalene reaction was extensively studied. Fifteen identifiable products were observed and conditions were found where the desired products, 1- and 2-t-butyl naphthyl ethers (V and VI) were formed in maximum yield, and their decomposition products, 1- and 2-naphthol (XIV and XV), were formed in minimum yield. The mole percent ratio of 1-substituted products (V and XIV) to 2-substituted products (VI and XV) was found under standardized conditions to be 0.35 ± 0.03 in every case when the halogen was I, Br and …

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The Reactivity And Selectivity Of The Reaction Of Sulfur Trioxide And Bromobenzene, Sullivan E. Blau Jun 1970

The Reactivity And Selectivity Of The Reaction Of Sulfur Trioxide And Bromobenzene, Sullivan E. Blau

Theses and Dissertations

The sulfonation of bromobenzene with sulfur trioxide in liquid sulfur dioxide at -12 to -13° C. was studied to determine its relative reactivity. The relative rate constant ratio, kbenzene/kbromobenzene, was found to be 28.6 in a competitive reaction between benzene and bromobenzene. The isomer distribution was found to be 0.15 ± 0.02% for the meta, 0.91 ± 0.04% for the ortho and 98.93 ± 0.14% for the para isomers. The partial rate factors were calculated to be pf= 0.208, of= 0.0096 and mf = 0.00018. The relative rate data exhibited a distinctive behaviour previously noted in related systems, possibly due …

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High Pressure Spectral Chemistry Of Selected Organic Compounds, Frank William Linsley Jun 1970

High Pressure Spectral Chemistry Of Selected Organic Compounds, Frank William Linsley

Theses and Dissertations

The series of compounds indicated by the formular C_6H_5-(CH=CH)n-C_6H_5 change in color from white (colorless) to yellow to orange to red to deep red as n increases from 1 to 12. Stilbene is the first compound of this series (n=1). Under pressure, exerted by a diamond anvil press, stilbene can be seen to change color from white to yellow to red as increasing pressure is applied. Similar color changes are observed for the compounds where n=2,3, and 4 when subjected to similar pressure. This study records and reports the spectra versus pressure for these compounds.

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Preparation Of New Amino-, Thio-, And Sulfonyladamantane Derivatives, Joseph Craig Argyle Jun 1970

Preparation Of New Amino-, Thio-, And Sulfonyladamantane Derivatives, Joseph Craig Argyle

Theses and Dissertations

Various synthetic schemes were used to prepare a number of new amino-thio- and sulfonyladamantane compounds. By a nucleophilic substitution on 1-bromoadamantane, 1-(p-nitrophenylthio)adamantane was prepared from p-nitrothiophenol; the amino- and sulfonyl- derivatives of this compound were also prepared. Silver tosylate was used to generate the 1-adamantyl carbonium ion from 1-bromoadamantane in a synthetically useful procedure for preparing 1-adamantylamides from nitriles. Three 1-(1-adamantylcarbinyl)-2,5-dialkylpyrroles were prepared by Knorr-Paal reactions and reduced to the corresponding pyrrolidines. Thio- and aminomethyl 1-adamantyl ketones were prepared from methyl and bromomethyl 1-adamantyl ketones, respectively. Aliphatic and aromatic oxiranes were reacted with 1-aminoadamantane in a bomb at elevated temperatures …

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The Synthesis And Properties Of New Potentially Chemotheraputic [Sic] Pteridine Derivatives, Walter Wesley Parish Jun 1970

The Synthesis And Properties Of New Potentially Chemotheraputic [Sic] Pteridine Derivatives, Walter Wesley Parish

Theses and Dissertations

A new general synthetic method for the preparation of 6-thiopteridines has been developed. The method involves the addition of thiols to intermediate pyrimidine nitrones formed in situ by the reaction of 4-amino-5-nitrosopyrimidines with pyridinium-activated acetonitriles, acetates, acetophenones, and other methylketones. Ca. forty new pteridines were prepared by this method. The preparation of six new 6-pteridinyl ketones, two new 6- pteridinyl ketone thiosemicarbazones, and two new 6-sulfonylpteridines and their 4-acetamido derivatives is also reported. 4-Acetamido-2- amino-7-phenylpteridine 5-oxide was prepared by the reaction of 2- amino-4,6-diacetamido-5-nitrosopyrimidine with either phenylsulfonyl-acetophenone or phenacylpyridinium bromide. Evidence relating to the structure of the acylated 4-amino-5- nitrosopyrimidines …

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Donor Properties Of Dimethylsulfoniumcyclopentadienylide And Tetramethylenesulfoniumcyclopentadienylide In Metal Complexes ; Part Ii. The Attempted Preparation Of Boron Tricyanide, Gary Scott Barney May 1970

Donor Properties Of Dimethylsulfoniumcyclopentadienylide And Tetramethylenesulfoniumcyclopentadienylide In Metal Complexes ; Part Ii. The Attempted Preparation Of Boron Tricyanide, Gary Scott Barney

Theses and Dissertations

Part I.--Complexes of dimethylsulfoniumcyclopentadientylide and tetramethylenesulfoniumcyclopentadienylide with metal ions were studied in order to determine the coordination site on the ylids. Infrared spectra indicate that the ylids are coordinated through the cyclopentadienyl ring in all complexes except for the Hg(CN)2 complexes. Coordination-of the HgI2, CdI2, ZnCl2, and AgNO3 complexes is through the number one position on the ring as suggested by NMR data. Infrared and NMR data strongly indicate that the ylids in the Hg(CN)2 complexes are coordinated through sulfur. Part II.--The only method given in the chemical literature for the preparation of boron tricyanide could not be duplicated in …

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Rayleigh Hysteresis Shape: Its Relationship To Displacement Distance Of A Single Domain Wall In 50% Ni–Fe, R. C. Woodbury, M. R. Hunt Mar 1970

Rayleigh Hysteresis Shape: Its Relationship To Displacement Distance Of A Single Domain Wall In 50% Ni–Fe, R. C. Woodbury, M. R. Hunt

Faculty Publications

The need to measure the displacement distance of domain walls from equilibrium for very weak alternating fields (H ≪ coercive force) in bulk magnetic material has prompted a study of the possible use of the opening of the Rayleigh hysteresis loop to indicate the amount of wall displacement. This paper contains (1) a review of the theoretical relationship between hysteresis shape and the displacement distance of a domain wall, based upon defect-energy models of Rodbell and Bean, and Baldwin; and (2) an experimental approach which provides a measure of the wall displacements versus hysteresis shape for 50% Ni–Fe tape. Discrepancies …

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