Comprehensive kinetic and thermodynamic study of the reactions of CO2(aq) and HCO3(-) with monoethanolamine (MEA) in aqueous solution

The temperature dependence of the reversible reaction between CO(2)(aq) and monoethanolamine (MEA) has been investigated using stopped-flow spectrophotometry by following the pH changes during the reactions with colored acid-base indicators. Multivariate global analysis of both the forward and backward kinetic measurements for the reaction of CO(2)(aq) with MEA yielded the rate and equilibrium constants, including the protonation constant of MEA carbamate, for the temperature range of 15-45 °C. Analysis of the rate and equilibrium constants in terms of the Arrhenius, Eyring, and van't Hoff relationships gave the relevant thermodynamic parameters. In addition, the rate and equilibrium constants for the slow, reversible reaction of bicarbonate with MEA are reported at 25.0 °C. At high pH, reactions of the amine with CO(2) and with bicarbonate are significant.     

Absolute Equivalence and Dirac Operators of Commuting Tuples of Operators

In this paper we define an equivalence relation of operators on Hilbert spaces which we call absolute equivalence. Two operators are called absolutely equivalent if both the absolute value of the operators and their adjoints are unitarily equivalent. We then use the properties of this equivalence relation to study the Koszul complex of a commuting tuple of operators through the Dirac operator of the tuple.     

Development of free radicals in sulfonated polystyrene ion-exchange resins upon drying

On exhaustive drying of sulfonated polystyrene-based ion-exchange resins, it is shown that free-radical centers develop. These have been examined by electron-spin resonance spectroscopy. The formation of the free radicals is largely reversible with respect to desorption and sorption of water which was measured by means of a quartz spiral microbalance. The spin-concentration isotherm as a function of sorbed water concentration is obtained. The presence of free radicals, dependent on water content in the resins, interferes with proton magnetic relaxation studies of hydration of ionized resins by providing a faster electron-spin coupled nuclear magnetic relaxation mechanism.     

The infrared spectrum of californium-249

The Cf-249 spectrum between 3700 and 12,000 cm^?1 has been recorded. The strongest 90 lines are listed.     

The use of a minicomputer for data collection and treatment in the study of electrochemical surface processes

Procedures for on-line acquisition and processing of data from controlled-potential (linear potential sweep and cyclic voltammetric) experiments on electrode surface processes by means of a PDP 11/34 minicomputer are described. Advantages of this procedure over regular recording of current—potential or current —time traces on an oscilloscope are discussed.     

Operators that are points of spectral continuity,II

This paper continues an earlier study of those bounded operators on a Hilbert space at which the spectrum is continuous, where the spectrum is considered as a function whose domain is the set of all bounded operators furnished with the norm topology and whose range is the collection of compact subsets of the complex plane furnished with the Hausdorff metric. In this paper the points of continuity of the essential spectrum, the approximate point spectrum, and certain related subsets of the spectrum are characterized.The first author was supported by National Science Foundation Grant MCS 77-28396.