Gas hydrates represent an unconventional methane resource and a production/safety risk to traditional oil and gas flowlines. In both systems, hydrate may share interfaces with both aqueous and hydrocarbon fluids. To accurately model macroscopic properties, such as relative permeability in unconventional systems or dispersion viscosity in traditional systems, knowledge of hydrate interfacial properties is required. This work presents hydrate cohesive force results measured on a micromechanical force apparatus, and complementary water-hydrocarbon interfacial tension data. By combining a revised cohesive force model with experimental data, two interfacial properties of cyclopentane hydrate were estimated: hydrate-water and hydrate-cyclopentane interfacial tension values at 0.32 ± 0.05 mN/m and 47 ± 5 mN/m, respectively. These fundamental physiochemical properties have not been estimated or measured for cyclopentane hydrate to date. The addition of surfactants in the cyclopentane phase significantly reduced the cyclopentane hydrate cohesive force; we hypothesize this behavior to be the result of surfactant adsorption on the hydrate-oil interface. Surface excess quantities were estimated for hydrate-oil and water-oil interfaces using four carboxylic and sulfonic acids. The results suggest the density of adsorbed surfactant may be 2× larger for the hydrate-oil interface than the water-oil interface. Additionally, hydrate-oil interfacial tension was observed to begin decreasing from the baseline value at significantly lower surfactant concentrations (1-3 orders of magnitude) than those for the water-oil interfacial tension.

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Localized agriculture is theorized to provide socio-environmental benefits to the community while ensuring a livelihood for local farmers. Much of the food systems literature refers to such an arrangement as civic agriculture, which is characterized as promoting community development by strengthening social ties among the various nodes of the localized food system. However, there is little literature that identifies the attributes of community and the specific mechanisms through which community qualities are produced, modeled, or replicated. This study's goal is to identify the meaning of community as used in the phrase "community supported agriculture" (CSA) by asking members and operators of local CSAs how they define community within the context of their membership. On-site interviews were conducted at the produce pick-up locations of four CSA farms in central Pennsylvania, resulting in a convenience sample of 97 CSA members and four operators. The survey instrument utilized open and closed-ended questions to collect information on farmer and member perceptions of their CSA community, motivations to join, and satisfaction with their experiences. The results suggest respondents are highly satisfied with products and services provided through their CSA. However, there are statistically significant differences in satisfaction scores across the four sampled farms. These differences support findings drawn from the open-ended questions indicating these CSA farms varied in member-defined attributes of a CSA community. Farm management practices, level of personal interactions, and other factors appear to have significant effects on CSA members' perception of community.