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On The Mechanism Of The Diels-Alder Reaction--Dimerization Of Trans-Phenylbutadiene, Michael Ward Mcnicholas Jan 1972

On The Mechanism Of The Diels-Alder Reaction--Dimerization Of Trans-Phenylbutadiene, Michael Ward Mcnicholas

Dissertations and Theses

The Diels-Alder dimerization of trans-1-substituted butadienes is expected to yield a cyclohexene adduct with the substituents in the 3 and 4 positions cis to one another. This prediction is based on past observations of other Diels-Alder additions. The cis-isomer is the only one consistent with a two-stage mechanism proposed by Woodward and Katz.

In the case of trans-phenylbutadiene, the expected adduct is cis-3-phenyl 1-4-(trans-styry1) cyclohexene. Alder, Haydn and Vogt, however, reported that the corresponding trans-isomer is the dimerization product. There is reason to believe that the observation of the trans-isomer may have been the result of product isomerization during purification. …


Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation Jan 1971

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation

Publications (WR)

Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …


Cyclization Studies Involving The Synthesis Of 5-Substituted-1-Naphthol, Clark Keelock Chow Jun 1969

Cyclization Studies Involving The Synthesis Of 5-Substituted-1-Naphthol, Clark Keelock Chow

Dissertations and Theses

The γ-o-substituted-phenylparaconic acids were prepared by a method patterned after that of Fuson. These paraconic acids were prepared in good yield. A re-investigation of the Perkin and Fittig methods of preparing γ-phenylisocrotonic acid was carried out without success.

The synthesis of γ-o-halophenylisocrotonic acids by thermal, and catalyzed decarboxylation of γ-o-halophenylparaconic acid, have been carried out in good yield. An effective catalyst, optimum temperature and reaction period of decarboxylation of the γ-o-halophenylparaconic acids have been determined. Infrared absorptions have characterized the γ-o-halophenylisocrotonic acids formed to be in the stable trans form. …


Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation Jun 1965

Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation

Publications (WR)

The survey results indicate that the impoundment of water behind Hoover Dam has not adversely affected the dissolved oxygen (DO) content and that water quality and DO content were uniform regardless of depth. The study made in April-May 1964 will provide water quality data of Lake Mead prior to releases from Lake Powell as a basis for evaluating Lake Powell's effect on water quality and limnology of Lake Mead. The performance of a DO analyzer was tested and found unsatisfactory at depths below 150 ft. Parameters tested by standard chemical analyses of water samples in the Denver Laboratory and by …


Chelation Of The Transition Metal Ions With A Series Of Polyhodrozyamine Compounds, William Percy Moore Jan 1956

Chelation Of The Transition Metal Ions With A Series Of Polyhodrozyamine Compounds, William Percy Moore

Master's Theses

Chelation was reviewed with emphasis on the work done by contemporary workers.

The following polyhydroxyamine compounds were synthesized, purified and· analyzed:

1,2-bis[tris(hydroxymethyl)methylamino]ethane dihydrochloride

1,3-b1s[tris(hydroxymethyl)methylamino]propane dihydrochloride

1,3-b1s[tris(hydroxymethyl)methylamino]-2-propanone dihydrochloride

1,2,3-tris[tris(hydroxymethyl)methylamino)propane tri­ hydrochloride

The latter two compounds have not been reported in the literature.

Chelates were prepared by reacting the above compounds, and 1-3bis[tris(hydroxymethyl)methylamino]-2-propanol dihydrochloride ("disec") and the "disec" free base, with the ions of the first transition metals. Stability cons­tants were obtained where appreciable coordination occurred before precipitation of the metallic ion took place . A list of the metal ions studied with one or more chelating agents follows: Cu+2, …


Collector-Depressant Equilibria For The Flotation System Potassium Ethyl Xanthate-Potassium Cyanide-Molybdenite, Connell Bolton Roberts Aug 1952

Collector-Depressant Equilibria For The Flotation System Potassium Ethyl Xanthate-Potassium Cyanide-Molybdenite, Connell Bolton Roberts

Theses and Dissertations

This dissertation involves a study of the collector-depressant equilibria of the flotation system potassium ethyl xanthate-potassium cyanide-molybdenite, based upon mineral-air bubble contact measurements made by a modified captive bubble technique. The Cook theory of single site free acid adsorption is used to interpret the data. The standard free energies of adsorption of ethyl xanthic acid and hydrocyanic acid on molybdenite are calculated.


The Pressing Need Of A Practical Non-Technical Course In High School Chemistry, P. M. Glasoe Apr 1939

The Pressing Need Of A Practical Non-Technical Course In High School Chemistry, P. M. Glasoe

Journal of the Minnesota Academy of Science

No abstract provided.