Physical Sciences and Mathematics Commons^™

Controlling The Number Of Metal Sites To Which A Poly(Tertiary Phosphine) Coordinates To Group 6 Metal Carbonyls, Nestor Paul Hansen

Masters Theses

The compounds trisdiphenylphosphine(tricarbonyl) metal and trisdiphenylvinylphosphine(tricarbonyl) metal of molybdenum and tungsten were prepared. These compounds were allowed to react with diphenylvinylphosphine and diphenylphosphine, respectively, in the presence of azobis(2-methyipropio)nitrile or potassium t-butoxide to yield the complex containing bis(diphenylphosphino) ethane as a chelated ligand.

The tris-substituted compounds showed a large degree of lability which prevented the isolation of the desired, (OC)₃M(Ph₂PCH₂CH₂PPh₂)₃, compound which contains three ditertiary phosphines acting as monodentate ligands.

Coordinated diphenylphosphine and diphenylvinylphosphine pentacarbonyl compounds of chromium, molybdenum and tungsten were prepared and allowed to react in …

A Laser Interferometric Study Of Electric Field Effects On Methane-Oxygen Flame Plasmas, Mark D. Prairie

Masters Theses

A laser interferometer is developed to study the refractive index field, aerodynamic structure, and three dimensional temperature profile of a methane-oxygen flame system under the influence of D.C. electric fields. A combined graphical-numerical method is used to transform the observed interference patterns into radial temperature distributions. The results indicate that the electric field exerts a marked influence on the flame stability, geometry, and charged particle flow. Experimental evidence shows that these effects are most apparent under fuel rich conditions. It is suggested an electric field may change the concentration gradients of reacting species, leading to an altered course of fuel …

Cleavage And Deoxygenation Of Phenolic Ethers, Derhsing Luu

Masters Theses

Dibromotriphenylphosphorane (DTP) in acetonitrile at 50°C was found to cleave ß-naphthylmethyl phenyl ether in preference to ß-naphthyl benzyl ether, 62% and 30% cleavage, respectively. Reaction of ß-naphthyl benzyl ether in dichloromethane at reflux produced 67% cleavage.

The quasiphosphonium complexes obtained by reaction of phenolic compounds with DTP were found to be reduced by several reducing reagents to give the corresponding aromatic hydrocarbons. Reaction of p-cresol with DTP, followed by lithium aluminum hydride reduction gave 38% toluene; sodium naphthalide reduction in THF gave 32% toluene; sodium in liquid ammonia reduction gave 12% toluene; sodium naphthalide reduction in DMF gave 15% toluene. …

The Interaction Of R. Leguminosarum 128c53 With Pea Root Proteins And A Comparison Of The Surface Polysaccharide With A Mutant Defective In Nodulation, Ru-Po Lee

Masters Theses

The Rhizobium extracellular polysaccharides (EPS) and lipopolysaccharides (LPS) are implicated in the symbiotic process. The interaction between host root protein fractions and symbiont EPS-polyacrylamide affinity support has been investigated. Ten percent root protein fractions had been observed to bind to the affinity support. The compositions of the polysaccharides from the parent R. leguminosarum and its Exo^-1 mutant have also been compared. The Exo^-1 mutant produces diminished amount of EPS and does not nodulate the host pea roots. Five kinds of polysaccharides from the parent were obtained: EPS, capsule polysaccharides (CPS I) washed from the bacteria with saline solution, …

A Comparison Of The Surface Polysaccharides From Rhizobium Japonicum Strains I110ars And 61a76str, And The Isolation Of Soybean Root Proteins Responsible For The Binding Of Eps From R. Japonicum Strain I110ars, Richard F. Koehler

Masters Theses

The surface polysaccharides of Rhizobium are implicated in the symbiotic process. The composition of the surface polysaccharides from two strains of Rhizobium japonicum, I110 ARS and 61A76 str, have been compared. Five polysaccharide fractions are obtained from the I110 ARS strain. They are the EPS (extracellular polysaccharide), CPS-1 and CPS-2 (capsular polysaccharide fractions), LPS (lipopolysaccharide) and Phe (polysaccharide found in the phenol layer from the phenol/water extraction). These polysaccharide fractions have identical sugar compositions. Four polysaccharide fractions are obtained from the 61A76 str strain. These are the EPS, CPS-1, SmPS (small molecular weight polysaccharide), and Phe. Each of these …

A Comparison Of The Surface Polysaccharides Of Rhizobium Trifolii Su843 With Its Genetically Altered Mutant, 8002, Which Is Defective At Root Hair Curling (Hac-), Elroy Alfredo Turnbull

Masters Theses

Bacteria of the genus Rhizobium are capable of forming a complex nitrogen fixing (fix⁺) symbiotic association with leguminous plants. The surface polysaccharides are believed to be essential in the symbiotic process. The surface polysaccharides of a genetically altered Rhizobium trifolii mutant, 8002--which does not cause root hair curling (HAC^-), forms no nodules (Nod^-) nor fixes nitrogen (Fix^-)--is compared with its parent, SU843, which causes root hair curling (HAC⁺), forms nodules (Nod⁺), and fixes nitrogen (Fix⁺). Three types of surface polysaccharides--extracellular polysaccharide(s) (EPS), capsular polysaccharide(s) (CPS), and …