The Marcellus Shale (MS) represents a large potential source of energy in the form of tightly trapped natural gas (NG). Producing this NG requires the use of energy and water, and has varying environmental impacts, including greenhouse gases. One well-established tool for quantifying these impacts is life-cycle assessment (LCA). This study collected information from current operating companies to perform a process LCA of production for MS NG in three areas--greenhouse gas (GHG) emissions, energy consumption, and water consumption--under both present (2011-2012) and past (2007-2010) operating practices. Energy return on investment (EROI) was also calculated. Information was collected from current well development operators and public databases, and combined with process LCA data to calculate per-well and per-MJ delivered impacts, and with literature data on combustion for calculation of impacts on a per-kWh basis during electricity generation. Results show that GHG emissions through combustion are similar to conventional natural gas, with an EROI of 12:1 (90% confidence interval of 4:1-13:1), lower than conventional fossil fuels but higher than unconventional oil sources.

We model the rolling motion of a fluid-driven, particle-filled microcapsule along a heterogeneous, adhesive substrate to determine how the release of the encapsulated nanoparticles can be harnessed to repair damage on the underlying surface. We integrate the lattice Boltzmann model for hydrodynamics and the lattice spring model for the micromechanics of elastic solids to capture the interactions between the elastic shell of the microcapsule and the surrounding fluids. A Brownian dynamics model is used to simulate the release of nanoparticles from the capsule and their diffusion into the surrounding solution. We focus on a substrate that contains a damaged region (e.g. a crack or eroded surface coating), which prevents the otherwise mobile capsule from rolling along the surface. We isolate conditions where nanoparticles released from the arrested capsule can repair the damage and thereby enable the capsules to again move along the substrate. Through these studies, we establish guidelines for designing particle-filled microcapsules that perform a 'repair and go' function and thus, can be utilized to repair damage in microchannels and microfluidic devices.

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Brazil's status as a rapidly developing country is visible in its need for more energy, including electricity. While the current electricity generation mix is primarily hydropower based, high-quality dam sites are diminishing and diversification to other sources is likely. We combined life-cycle data for electricity production with scenarios developed using the IAEA's MESSAGE model to examine environmental impacts of future electricity generation under a baseline case and four side cases, using a Monte-Carlo approach to incorporate uncertainty in power plant performance and LCA impacts. Our results show that, under the cost-optimal base case scenario, Brazil's GHGs from electricity (excluding hydroelectric reservoir emissions) rise 370% by 2040 relative to 2010, with the carbon intensity per MWh rising 100%. This rise would make Brazil's carbon emissions targets difficult to meet without demand-side programs. Our results show a future electricity mix dominated by environmental tradeoffs in the use of large-scale renewables, questioning the use tropical hydropower and highlighting the need for additional work to assess and include ecosystem and social impacts, where information is currently sparse. OPEN ACCESSEnergies 2013, 6 3183

Sarah Brownell is a Lecturer in Design Development and Manufacturing for the Kate Gleason College of Engineering at the Rochester Institute of Technology. She works extensively with students in the multidisciplinary engineering capstone design course and other project based elective courses, incorporating human centered design, participatory development, and design for development themes. She was a cofounder of the non-profit Sustainable Organic Integrated Livelihoods (SOIL) which promotes ecological sanitation in Haiti. Alexander Dale is the Executive Director of Engineers for a Sustainable World (ESW) and an adjunct faculty member at the University of Pittsburgh. His academic background is in energy and water policy, life-cycle assessment, and sustainable design. As one of the re-founders of ESW, he has focused on expanding educational opportunities as well as new engagement for faculty and professionals.c American Society for Engineering Education, 2015 Page 26.508.1 Development and Application of the Sustainability Skills and Dispositions Scale to the Wicked Problems in Sustainability InitiativeAbstract Throughout engineering curriculum there has been a growing focus on sustainability-related learning objectives, oftentimes with the ultimate learning goals being instilling dispositions such as the awareness of the environmental impact of engineering outcomes or concern towards social justice issues. Within this paper, we first provide an overview of an instrument we have developed to evaluate students' attainment of analogous learning objectives. This instrument, the Sustainability Skills and Dispositions Scale (SSDS), was designed to measure four sustainabilityrelated outcomes: (a) confidence in responding to wicked problems and awareness of (b) global, (c) social, and (d) environmental responsibilities as a designer. The SSDS was implemented pre-post within a course context as part of a multi-university initiative called the Wicked Problems in Sustainability Initiative (WPSI) during the Fall of 2014.The primary objective of this paper was to provide an overview of the reliability of the SSDS and to consider where the SSDS may still be improved for optimal alignment with WPSI objectives and outcomes. Our secondary goal was to consider where WPSI may be improved in the future in light of the survey results, which included the survey items and written reflections.To accomplish this second goal, we first used the SSDS items to compare pre-and post-course responses overall and on a course-by-course basis. To corroborate findings from this quantitative component, and to elucidate how both WPSI and the SSDS may be refined and improved, our secondary goal was pursued through content analysis of students' post-course written reflections. Participating instructors' experiences within WPSI were juxtaposed against these qualitative and quantitative findings to discuss broader implications for engineering education curriculum and to consider future recommendations for WPSI.