Aiming High for Virginia Colleges

Considerable discussion about higher education is likely to take place throughout 1999 from the current legislative session through December, when the report of the Governor\u27s Blue Ribbon Commission on Higher Education is anticipated. Because faculty teach, conduct research and provide service to all Virginians, we have a unique perspective on what will be needed to ensure the continuing excellence of higher education in Virginia. Toward that end, we offer the observations below on funding practices, simplifying bureaucratic procedures, improving research and scholarship, and governance in higher education. We believe positive change can make real differences in the quality of the services and programs we provide

Solvent effects on the ionic decomposition of t-butylperoxyformate : and empirical correlation of rate with solvent properties

Rate constants for the pyridine catalyzed ionic decomposition of t-butylperoxyformate (TBF) are measured in 15 non-hydroxylic solvents. The second order rate constants varied by a factor of 40 from the "slowest" solvent, tetra-chloroethylene, to the "fastest", 1,2-dichloroethahe. Ten different empirical equations are found and their ability to correlate the rate constants with bulk solvent properties is compared. The best of the ten equations involves the polarizability and dipole moment of the solvent as follows. log krel = 1.207 (no²-1/no²+2) + 3.99 μ + 0.003 -3 The rate constants for TBF decomposition in other non-hydroxylic solvents are calculated by the empirical equations and are compared with values previously reported. The average deviation of the log k is 0.22. The rate constants for the reaction of methyl iodide with triethylamine are calculated from solvent properties and the values compared to literature values. In this case the average deviation of the log k is 0.31.Science, Faculty ofChemistry, Department ofGraduat

Reactions in frozen solutions

In order to try to explain some of the rather surprising features of reactions in frozen solutions, four different systems are extensively studied. They are the reaction of methyl iodide with triethylamine to form the quaternary ammonium salt in frozen benzene, the base catalyzed decomposition of t-butyl-peroxy formate to carbon dioxide and t-butyl alcohol in frozen p-xylene, the reaction of ethylene chlorohydrin with hydroxide ion to form ethylene oxide in frozen aqueous solution and the mutarotation of glucose in ice. In addition, a demonstration experiment is presented in which iodide ion is oxidized to iodine by arsenic acid in frozen aqueous solution. Several new features of reactions in frozen solutions are reported; including a maximum in the rate - temperature dependence curve, rate enhancements as large as 1000 - fold over reaction in unfrozen solutions and shifts in the equilibrium position. Kinetic equations are developed which correlate all of the results and which also explain some of the observations of other investigators. These equations are based upon the assumptions that (1) when a solution containing reactive species is frozen all of the reactants as well as any other solutes present are rejected by the crystallizing solvent and are concentrated into regions which remain liquid and that (2) the reaction proceeds normally in these regions. The fundamental equation used for correlating the rate data for the second-order reactions studied is, [formula omitted] where Vn is the total volume of the liquid regions, mA is the total moles of reactant A present in the system at any time and Ah and Bh are the concentrations of the reactants A and B in the liquid regions. The ideas developed for the treatment of reactions in frozen solutions are extended to reactions in organic solids which have a melted phase present. This treatment accounts qualitatively for the observations made on mutarotation in solid glucose. The application of the method to the isomerization of 5-norbornene-2,3-endo-dicarboxylic/anhydride to the exo-isomer allows separation of concurrent reactions in the melt and in the solid.Science, Faculty ofChemistry, Department ofGraduat

User-Controlled Generalization Boundaries for p-Sensitive k-Anonymity

Numerous privacy models based on the k-anonymity property and extending the k-anonymity model have been introduced in the last few years in the data privacy research: l-diversity, psensitive k-anonymity, t-closeness, etc. While differing in their methods and the quality of their results, they all focus on first masking the data, then protecting the quality of the data as a whole. We considered a new approach, imposing requirements on the amount of distortion allowed on the initial data in order to preserve its usefulness. Specifying quasi-identifier generalization boundaries, we achieved p-sensitive k-anonymity within the imposed boundaries. Limiting the amount of generalization when masking microdata is indispensable for real-life datasets and applications. We defined the constrained p-sensitive k-anonymity model and presented an algorithm for generating constrained p-sensitive k-anonymous microdata. Our experiments showed that the proposed algorithm is comparable with existing algorithms used for generating p-sensitive k-anonymity with respect to the results’ quality, while the obtained masked microdata obviously complies with the user’s generalization boundaries