Trees,generally,are used to remove carbon dioxide from the atmosphere.Other methods need to be considered.NASA(National Aeronautics and Space Administration)uses iron lime to increase the plankton uptake from the ocea...Trees,generally,are used to remove carbon dioxide from the atmosphere.Other methods need to be considered.NASA(National Aeronautics and Space Administration)uses iron lime to increase the plankton uptake from the ocean bed.We can remove the carbon through the practice of shellfish farming.In French Polynesia,oysters mean pearl oyster farming.An independent assessment of the shellfish industry would be required to determine the carbon sequestration and generate carbon offsets through this method.CO2 sink in pearl oysters shell,called MOP(Mother Of Pearl)can be allocated into precious button and objects or powder in poultry farming.展开更多
Emissions trading schemes(ETSs)have been a central component of international climate change policies,as a carbon pricing tool to achieve emissions reduction targets.Forest carbon offset credits have been leveraged in...Emissions trading schemes(ETSs)have been a central component of international climate change policies,as a carbon pricing tool to achieve emissions reduction targets.Forest carbon offset credits have been leveraged in many ETSs to efficiently meet emission reduction targets,yet there is little knowledge about the perceptions,experiences,and challenges associated with the forest carbon offsetting in existing and pilot ETS.Given that the future inclusion of forest carbon offset in ETS management activities and policies will require strong support and acceptability among the institutions and experts involved in ETS,this study explores the experiences and lessons learned with 16 globally engaging experts representing major existing ETSs(North America,Europe,and New Zealand)and Chinese pilot ETSs towards the inclusion of forestry offsets,major concerns and challenges with existing implementation models.Findings revealed that many respondents particularly from North America,New Zealand,and Chinese pilot systems portrayed positive attitudes toward the inclusion of forestry carbon offsets and its role in contributing to a viable ETS,while European experts were not supportive.Respondents cited leakage,permanence,additionality,and monitoring design features as the major challenges and concerns that inhibit the expansion and inclusion of forest carbon offsetting.Respondents from Chinese pilot schemes referenced a unique set of challenges related to implementation,including the increasing cost of afforestation and reforestation projects,the uncertainty in the future supply and demand for their national Certified Emissions Reduction(CER)scheme and landowner engagement.Existing and future ETSs should learn from and address the challenges experienced by global experts and carbon pricing mechanisms to design,evaluate,or enhance their forest carbon offset programs for an effective and viable system that successfully contributes to GHG mitigation practices globally.We recommend inclusion of forest carbon offsets at the early stages of ETS improves the perceptions and experience of policy makers and practitioners toward the success and potential of forestry offsets in ETS ensuring familiarity and confidence in the mechanism.展开更多
The US Green Building Council’s (USGBC) Leadership in Energy and Environmental Design (LEED) green buildingrating program has grown from a little known tool for market change to a label and brand relied upon by many ...The US Green Building Council’s (USGBC) Leadership in Energy and Environmental Design (LEED) green buildingrating program has grown from a little known tool for market change to a label and brand relied upon by many ofthe largest players in real estate. It now serves as an indicator of sustainability and an instrument for environmentalmanagement. While LEED-certifi ed buildings tend to offer greater environmental benefi ts than their conventionalcounterparts, research and experience shows that the variation in and magnitude of these benefi ts varies, even amongbuildings of the same LEED certifi cation level. In light of growing concerns about “greenwashing” and the liabilityassociated with questionable environmental declarations, it is important to ensure that users of LEED and similarcertifi cation programs receive a set of benefi ts comparable to those expected. With a focus on energy-related issues, thisresearch (1) highlights evidence of the inconsistency between the expected and actual benefi ts of LEED buildings, (2)suggests revisions to LEED’s Energy & Atmosphere (EA) section to reduce the variation and magnitude in the energyrelatedenvironmental impacts from LEED buildings, (3) quantifi es this reduction in variation and magnitude ofimpacts using Monte Carlo analyses and probabilistic models created specifi cally for this research, (4) compares carbondioxide emissions from LEED buildings to the Architecture 2030 Challenge goals and (5) quantifi es the importanceof scoring LEED buildings on a per capita normalized basis. This research is a follow-up piece to the authors’ previouswork published in the Journal of Green Building (Wedding and Crawford-Brown 2007).展开更多
Band offset is a dominant factor affecting the photocatalytic performance of heterostructure photocatalysts. Therefore, controlling the band gap structure of semiconductors is a key challenge in the development of eff...Band offset is a dominant factor affecting the photocatalytic performance of heterostructure photocatalysts. Therefore, controlling the band gap structure of semiconductors is a key challenge in the development of efficient photocatalysts. We used a typical in situ-method to prepare diverse graphite-phase carbon nitride(g-C_3N_4)samples from melamine, thiourea, and a mixture thereof,and found that they exhibited band gaps between2.3–2.8 e V. From UV–Vis spectra and X-ray photoelectron spectroscopy measurements, we determined that the g-C_3N_4 samples exhibited different band gap values and valence band positions. On this basis, we constructed g-C_3N_4/m-La VO_4 heterojunctions with different band offsets. UV–Vis spectra and X-ray photoelectron spectroscopy measurements revealed that the valence band offsets(VBOs) of the different heterojunctions were similar, but their conduction band offsets(CBOs) were significantly different. Photocatalytic experiments revealed that the reaction rate was enhanced with an increase in the CBO value. Furthermore, the three-phase g-C_3N_4/g-C_3N_4/mLa VO_4 heterojunction composed of m-La VO_4 and mixed g-C_3N_4 showed the highest photocatalytic activity, which was mainly due to the construction of a multilevel structure. This work investigates the influence of the band offset on heterojunction photoelectrochemical properties and provides a new strategy to improve the photocatalytic activity by constructing multilevel structures.展开更多
文摘Trees,generally,are used to remove carbon dioxide from the atmosphere.Other methods need to be considered.NASA(National Aeronautics and Space Administration)uses iron lime to increase the plankton uptake from the ocean bed.We can remove the carbon through the practice of shellfish farming.In French Polynesia,oysters mean pearl oyster farming.An independent assessment of the shellfish industry would be required to determine the carbon sequestration and generate carbon offsets through this method.CO2 sink in pearl oysters shell,called MOP(Mother Of Pearl)can be allocated into precious button and objects or powder in poultry farming.
基金funded by the China Green Carbon Foundation and the Faculty of Forestry,University of British Columbia。
文摘Emissions trading schemes(ETSs)have been a central component of international climate change policies,as a carbon pricing tool to achieve emissions reduction targets.Forest carbon offset credits have been leveraged in many ETSs to efficiently meet emission reduction targets,yet there is little knowledge about the perceptions,experiences,and challenges associated with the forest carbon offsetting in existing and pilot ETS.Given that the future inclusion of forest carbon offset in ETS management activities and policies will require strong support and acceptability among the institutions and experts involved in ETS,this study explores the experiences and lessons learned with 16 globally engaging experts representing major existing ETSs(North America,Europe,and New Zealand)and Chinese pilot ETSs towards the inclusion of forestry offsets,major concerns and challenges with existing implementation models.Findings revealed that many respondents particularly from North America,New Zealand,and Chinese pilot systems portrayed positive attitudes toward the inclusion of forestry carbon offsets and its role in contributing to a viable ETS,while European experts were not supportive.Respondents cited leakage,permanence,additionality,and monitoring design features as the major challenges and concerns that inhibit the expansion and inclusion of forest carbon offsetting.Respondents from Chinese pilot schemes referenced a unique set of challenges related to implementation,including the increasing cost of afforestation and reforestation projects,the uncertainty in the future supply and demand for their national Certified Emissions Reduction(CER)scheme and landowner engagement.Existing and future ETSs should learn from and address the challenges experienced by global experts and carbon pricing mechanisms to design,evaluate,or enhance their forest carbon offset programs for an effective and viable system that successfully contributes to GHG mitigation practices globally.We recommend inclusion of forest carbon offsets at the early stages of ETS improves the perceptions and experience of policy makers and practitioners toward the success and potential of forestry offsets in ETS ensuring familiarity and confidence in the mechanism.
基金supported by the Institute for theEnvironment at the University of North Carolina(UNC) at Chapel Hill and Cherokee InvestmentPartners.
文摘The US Green Building Council’s (USGBC) Leadership in Energy and Environmental Design (LEED) green buildingrating program has grown from a little known tool for market change to a label and brand relied upon by many ofthe largest players in real estate. It now serves as an indicator of sustainability and an instrument for environmentalmanagement. While LEED-certifi ed buildings tend to offer greater environmental benefi ts than their conventionalcounterparts, research and experience shows that the variation in and magnitude of these benefi ts varies, even amongbuildings of the same LEED certifi cation level. In light of growing concerns about “greenwashing” and the liabilityassociated with questionable environmental declarations, it is important to ensure that users of LEED and similarcertifi cation programs receive a set of benefi ts comparable to those expected. With a focus on energy-related issues, thisresearch (1) highlights evidence of the inconsistency between the expected and actual benefi ts of LEED buildings, (2)suggests revisions to LEED’s Energy & Atmosphere (EA) section to reduce the variation and magnitude in the energyrelatedenvironmental impacts from LEED buildings, (3) quantifi es this reduction in variation and magnitude ofimpacts using Monte Carlo analyses and probabilistic models created specifi cally for this research, (4) compares carbondioxide emissions from LEED buildings to the Architecture 2030 Challenge goals and (5) quantifi es the importanceof scoring LEED buildings on a per capita normalized basis. This research is a follow-up piece to the authors’ previouswork published in the Journal of Green Building (Wedding and Crawford-Brown 2007).
基金supported by the National Natural Science Foundation of China(21173131)the Taishan Scholar Project of Shandong Province
文摘Band offset is a dominant factor affecting the photocatalytic performance of heterostructure photocatalysts. Therefore, controlling the band gap structure of semiconductors is a key challenge in the development of efficient photocatalysts. We used a typical in situ-method to prepare diverse graphite-phase carbon nitride(g-C_3N_4)samples from melamine, thiourea, and a mixture thereof,and found that they exhibited band gaps between2.3–2.8 e V. From UV–Vis spectra and X-ray photoelectron spectroscopy measurements, we determined that the g-C_3N_4 samples exhibited different band gap values and valence band positions. On this basis, we constructed g-C_3N_4/m-La VO_4 heterojunctions with different band offsets. UV–Vis spectra and X-ray photoelectron spectroscopy measurements revealed that the valence band offsets(VBOs) of the different heterojunctions were similar, but their conduction band offsets(CBOs) were significantly different. Photocatalytic experiments revealed that the reaction rate was enhanced with an increase in the CBO value. Furthermore, the three-phase g-C_3N_4/g-C_3N_4/mLa VO_4 heterojunction composed of m-La VO_4 and mixed g-C_3N_4 showed the highest photocatalytic activity, which was mainly due to the construction of a multilevel structure. This work investigates the influence of the band offset on heterojunction photoelectrochemical properties and provides a new strategy to improve the photocatalytic activity by constructing multilevel structures.
