Data on hydrodynamic and thermodynamic properties of several well-defined, linear flexible polymer chains in thermodynamically good solvents and theta solvents are tabulated and critically evaluated. The polymers considered are 1,4-polybutadiene, 1,4-polyisoprene, polyisobutylene, polystyrene, and poly(a-methylstyrene). Extensive data, obtained as a function of molecular weight, are evaluated for the intrinsic viscosity, radius of gyration, hydrodynamic radius, and second virial coefficient. The resulting power law relationships between the measured properties and polymer molecular weight are reported.

The dilute-solution transport properties of polyisobutylene (PIB) fractions have been measured under conditions and in good solvents of varying thermodynamic quality. The translational diffusion coefficients were evaluated via photon correlation spectroscopy and coupled with the results from intrinsic viscosity and low-angle laser light scattering experiments to yield the appropriate size parameters. The results allow a comparison of the properties of PIB with those of other flexible chains and with various theoretical predictions.

Dilute solution properties of poly(a-methylstyrene) (PaMS) in toluene at 25 °C were studied by static and dynamic light scattering and intrinsic viscosity measurements. Some of the experimental values of universal ratios of static and dynamic quantities are found to be in agreement with theoretical calculations corresponding to the least-draining self-avoiding limit. In most cases, renormalization group calculations of Oono agree somewhat better with experimental findings than those results of the renormalized two-parameter theory of Douglas and Freed or the numerical quadrature analysis of Barrett. Experimental results for poly(styrene) in various good solvents are included in the comparison of theory and experiment. In those instances where good agreement with theory is not obtained, departures from the least-draining limit may be responsible, although it is possible that the self-avoiding limit is not reached even for the highest molecular weight PaMS samples investigated. In addition, the value of the conformational parameter, p, for PaMS/toluene was found to equal 1.54, whereas earlier results indicated p = 2.0 for the same polymer-solvent system. Reasons for this discrepancy are described.

An early field project of the Southeast Regional Carbon Sequestration Partnership (SECARB) was conducted in Cranfield oil field, western Mississippi. Carbon dioxide (CO 2 ) was injected into coarse-grained fluvial deposits of the Cretaceous lower Tuscaloosa formation, forming a gentle anticline at depths of 3300 m. CO 2 injection started in July 2008, increasing to 23 wells (as of May 2011), with total injection rates greater than 1 million tons/yr. Focused monitoring programs of the deep subsurface and near surface have been implemented in different study areas. Here we present results of the near-surface monitoring program over a 3year period, including shallow groundwater monitoring and soilgas monitoring. A general methodology of detecting CO 2 leakage into shallow groundwater chemistry is proposed. A set of geochemical indicator parameters was identified on the basis of the characterization of groundwater geochemistry, and these were further tested and validated using numerical modeling approaches, laboratory experiments, and field experiments. For soil-gas monitoring, a site (P-site) containing a plugged and abandoned well, a nearby open pit, and an engineered pad (representing a typical industrial near-surface environment for soil-gas monitoring) was selected for detailed study. The site was heavily instrumented with various sensors for measuring soil-gas concentrations at different depths, soil-water content, matric potential, and weather information. Three monitoring technologies were assessed: soil CO 2 concentration measurements, CO 2 flux measurements on the land surface, and multiple soil-gas component measurements. Results indicate that soil-gas-component measurements provide reliable information for gas-leakage detection. Methodologies of nearsurface monitoring developed in this study can be used to improve CO 2 -leakage monitoring at other CO 2 sequestration projects. This early field project was funded by the US Department of Energy, National Energy Technology Laboratory, as part of the Regional Carbon Sequestration Partnerships (RCSP) program. SECARB is led by the Southern States Energy Board (SSEB).

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