Browsing by Author "Wang, Yifei"

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    Economic Viability of Blue Carbon Offsets in Coastal North Carolina & Louisiana
    (2013-04-26) Dong, Xiaoyun; Wang, Yifei; Moss, Leland; Kraft, Natalie
    Carbon offsets are becoming a necessary tool in carbon emission reduction. The offsets obtained through sequestration in coastal wetland vegetation and sediment is referred to as blue carbon. Our client, the Duke Carbon Offset Initiative (DCOI), is currently researching blue carbon to help meet Duke University’s goal of carbon neutrality by 2024. Through cost-benefit analyses and stakeholder collaboration a matrix was constructed to a) characterize the current state of blue carbon opportunities in North Carolina and Louisiana and b) guide DCOI’s development of a blue carbon decision. The unit cost of a blue carbon project in North Carolina is 170 times greater than the cost in Louisiana, mainly due to the lack of wetland restoration infrastructure in North Carolina. Environmental factors, such as land conversion and sea level rise, have a significant effect on the feasibility of the blue carbon projects. Although net wetland loss rate is low in North Carolina, the total converted wetland area is large. These areas are undesirable for blue carbon projects as they lack permanence. A risk analysis shows that in the Albemarle-Pamlico Peninsula, there are low elevation counties with a lower wetland replacement rate; these areas are more prudent choices for blue carbon project sites. In addition, an analysis of sea level rise impacts indicates that due to smaller critical tidal range, Louisiana has a higher carbon sequestration rate than North Carolina when sea level rises from 0.1-1 cm/year, not taking into account natural disturbances. Recommendations from this broad assessment of blue carbon include identifying potential sites for economical pilot studies and monitoring policy developments.
  • Thumbnail Image
    ItemOpen Access
    Economic Viability of Blue Carbon Offsets in Coastal North Carolina & Louisiana
    (2013-04-26) Wang, Yifei; Dong, Xiaoyun; Kraft, Natalie; Moss, Leland
    Carbon offsets are becoming a necessary tool in carbon emission reduction. The offsets obtained through sequestration in coastal wetland vegetation and sediment is referred to as blue carbon. Our client, the Duke Carbon Offset Initiative (DCOI), is currently researching blue carbon to help meet Duke University’s goal of carbon neutrality by 2024. Through cost-­‐benefit analyses and stakeholder collaboration a matrix was constructed to a) characterize the current state of blue carbon opportunities in North Carolina and Louisiana and b) guide DCOI’s development of a blue carbon decision. The unit cost of a blue carbon project in North Carolina is 170 times greater than the cost in Louisiana, mainly due to the lack of wetland restoration infrastructure in North Carolina. Environmental factors, such as land conversion and sea level rise, have a significant effect on the feasibility of the blue carbon projects. Although net wetland loss rate is low in North Carolina, the total converted wetland area is large. These areas are undesirable for blue carbon projects as they lack permanence. A risk analysis shows that in the Albemarle-­‐Pamlico Peninsula, there are low elevation counties with a lower wetland replacement rate; these areas are more prudent choices for blue carbon project sites. In addition, an analysis of sea level rise impacts indicates that due to smaller critical tidal range, Louisiana has a higher carbon sequestration rate than North Carolina when sea level rises from 0.1-­‐1 cm/year, not taking into account natural disturbances. Recommendations from this broad assessment of blue carbon include identifying potential sites for economical pilot studies and monitoring policy developments.
  • Thumbnail Image
    ItemOpen Access
    Economic Viability of Blue Carbon Offsets in Coastal North Carolina & Louisiana
    (2013-04-26) Kraft, Natalie; Moss, Leland; Dong, Xiaoyun; Wang, Yifei
    Carbon offsets are becoming a necessary tool in carbon emission reduction. The offsets obtained through sequestration in coastal wetland vegetation and sediment is referred to as blue carbon. Our client, the Duke Carbon Offset Initiative (DCOI), is currently researching blue carbon to help meet Duke University’s goal of carbon neutrality by 2024. Through cost-benefit analyses and stakeholder collaboration a matrix was constructed to a) characterize the current state of blue carbon opportunities in North Carolina and Louisiana and b) guide DCOI’s development of a blue carbon decision. The unit cost of a blue carbon project in North Carolina is 170 times greater than the cost in Louisiana, mainly due to the lack of wetland restoration infrastructure in North Carolina. Environmental factors, such as land conversion and sea level rise, have a significant effect on the feasibility of the blue carbon projects. Although net wetland loss rate is low in North Carolina, the total converted wetland area is large. These areas are undesirable for blue carbon projects as they lack permanence. A risk analysis shows that in the Albemarle-Pamlico Peninsula, there are low elevation counties with a lower wetland replacement rate; these areas are more prudent choices for blue carbon project sites. In addition, an analysis of sea level rise impacts indicates that due to smaller critical tidal range, Louisiana has a higher carbon sequestration rate than North Carolina when sea level rises from 0.1-1 cm/year, not taking into account natural disturbances. Recommendations from this broad assessment of blue carbon include identifying potential sites for economical pilot studies and monitoring policy developments.
  • Thumbnail Image
    ItemOpen Access
    Economic Viability of Blue Carbon Offsets in Coastal North Carolina & Louisiana
    (2013-04-26) Kraft, Natalie; Moss, Leland; Dong, Xiaoyun; Wang, Yifei
    Carbon offsets are becoming a necessary tool in carbon emission reduction. The offsets obtained through sequestration in coastal wetland vegetation and sediment is referred to as blue carbon. Our client, the Duke Carbon Offset Initiative (DCOI), is currently researching blue carbon to help meet Duke University’s goal of carbon neutrality by 2024. Through cost-benefit analyses and stakeholder collaboration a matrix was constructed to a) characterize the current state of blue carbon opportunities in North Carolina and Louisiana and b) guide DCOI’s development of a blue carbon decision. The unit cost of a blue carbon project in North Carolina is 170 times greater than the cost in Louisiana, mainly due to the lack of wetland restoration infrastructure in North Carolina. Environmental factors, such as land conversion and sea level rise, have a significant effect on the feasibility of the blue carbon projects. Although net wetland loss rate is low in North Carolina, the total converted wetland area is large. These areas are undesirable for blue carbon projects as they lack permanence. A risk analysis shows that in the Albemarle-Pamlico Peninsula, there are low elevation counties with a lower wetland replacement rate; these areas are more prudent choices for blue carbon project sites. In addition, an analysis of sea level rise impacts indicates that due to smaller critical tidal range, Louisiana has a higher carbon sequestration rate than North Carolina when sea level rises from 0.1-1 cm/year, not taking into account natural disturbances. Recommendations from this broad assessment of blue carbon include identifying potential sites for economical pilot studies and monitoring policy developments.
  • Thumbnail Image
    ItemOpen Access
    Probing Mechanical Activation of Covalent Chemistry in Crosslinked Polymer Gels
    (2013) Wang, Yifei

    Toughness, the measure of how much energy a material can absorb before rupture, is an important property of materials. It has been demonstrated that the toughness of a single polymer chain of gem-dihalocyclopropane (gDHC) functionalized polybutadiene (PB) is increased dramatically over PB alone, due to the mechanically triggered electrocyclic ring opening reaction of gDHC into 2,3-dibromoalkenes. This thesis explores whether this molecular mechanical property can also be manifested in bulk material properties. Crosslinked gem-dichlorocyclopropane (gDCC) embedded PB polymers were swollen in various solvents, and the resulting gels were mechanically deformed under tensile stress. Young's modulus and fracture toughness were compared among PBs with gDCC incorporated in the backbones and/or crosslinking positions. The results showed that the incorporation of gDCC does not measurably increase the fracture toughness of the crosslinked polymer gels. Neither NMR nor FT-IR characterization of the post-test samples revealed detectable activation of the gDCC in the crosslinked PB. Further experiments will be focused on optimizing the polymer structure and testing methods to more effectively transfer the macroscopic force to the mechanophore in the material and continuing exploring the correlation between molecular responses and changes in macroscopic properties.