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Includes bibliographical references (p. 17-19).
Palladium-catalyzed cross-coupling of ??-substituted allylic silanolates with aryl bromides was investigated. It was discovered that ??-selectivity is heavily influenced by the substituents at silicon. It is proposed that undergoing an activated pathway significantly lowers the selectivity of the reaction. A major side-product of this reaction was discovered and conditions were developed to suppress the undesired reaction. It is proposed that the side reaction shares at least two intermediates with the desired cross-coupling reaction. The use of arsenic ligands and elevated temperatures mildly suppressed the side-reaction and further studies are needed to completely prevent the unwanted pathway from occurring.
The development and application of a 1,2-differentiated bissilylethene moiety has been studied. Moderate yields are obtai...
Three essays in empirical corporate finance
An aggregative growth model has been developed and tested with rate and particle size distribution data gathered under various reaction conditions. Smoluchowski population balance equations with a source term were solved for conditions applicable to the precipitations studied. Size dependant aggregation rate constants were determined from estimates of particle properties. By assuming that particles grow solely by aggregation, the model provides good estimates of final particle size distribution parameters from measured reaction rates.
Factors affecting amplitudes of fluctuation during 39 population cycles of Microtus ochrogaster and 20 cycles of M. pennsylvanicus were studied in alfalfa, bluegrass and tallgrass habitats over a 25-year period.
Population demography of the northern short-tailed shrew, Blarina brevicauda, was studied for 25 years in bluegrass, alfalfa, and tallgrass habitats in east-central Illinois. The population in bluegrass had higher over-winter population density, began increasing earlier in the year, peaked earlier in the year, had higher mean monthly population densities and amplitudes of fluctuation, and remained higher longer than did populations in alfalfa and tallgrass. Survival rates and persistence were greater in bluegrass and tallgrass than in alfalfa. The species displayed annual population fluctuations with little variation in amplitude among years in all three habitats. Seasonal reproduction appeared responsible for the annual fluctuations. Survival did not vary in relation to season, but was positively correlated with annual peak densities ...
Piezoelectric properties of three sol-gel derived Pb(Zr0.53Ti0.47)O3 thin film specimens of different thicknesses integrated onto Pt/Ti/SiO2||Si substrates are investigated to delineate the influence of residual stress on the strain-field response characteristics from other thickness related effects. Residual tensile stresses are determined from wafer curvature measurements for films ranging in thickness from 190 to 500 nm. Field-induced strains are measured interferometrically for each film under either a large ac driving voltage or a small ac ripple applied over a range of dc biases. Higher residual stresses decrease measured piezoelectric response, while thickness variations with no accompanying change in residual stress state produce little change in strain-field behavior. The diminished performance associated with high residual...
Since rhetorical criticism is the means by which the issues of political action and judgment are raised, the individual essays contribute to particular research areas aside from the overarching concern with social action. The following texts are critically examined: opinion essays on the artificial heart, Reagan's presidential addresses, two television episodes, and Jesus' use of parables.
Preparation to teach school mathematics should include developing an understanding of classroom mathematical interactions. The research literature and professional expertise agree that a teacher???s ability to respond to classroom mathematical interactions depends on her understanding of the subject matter within pedagogical situations. As a consequence, teacher education programs try to cultivate the novice teacher???s ability to respond to classroom mathematical interactions by developing the integration of mathematical and pedagogical thinking. This study re-evaluates that commitment, giving attention to current cognitive models of teachers??? integration of knowledge and to practice-based approaches to teacher learning. Unlike previous studies on teachers??? professional knowledge, this research provides a micro-perspective on teac...
