Climate change is widely recognized as the major environmental problem facing the globe today. One of the most urgent environmental problems facing shipping industry is the reduction of GHG (greenhouse gas) emission...Climate change is widely recognized as the major environmental problem facing the globe today. One of the most urgent environmental problems facing shipping industry is the reduction of GHG (greenhouse gas) emissions from its operations. Given the growing concern of the international community on "the deep reduction of global GHG emissions", it cannot be expected that the non-regulation of maritime GHG emissions can further continue. This paper investigates the main challenges and threats of the development of two MBMs (market-based measures) for the reduction of GHG emissions from international shipping, i.e., the "global levy scheme on maritime GHG emissions" and the "maritime emission trading scheme". A SWOT (strengths weaknesses opportunities threat) analysis is used, in this survey, to evaluate the environmental effectiveness as well as the easiness of implementation of the two policy options. Moreover, we make apparent their strengths and weaknesses concerning abatement of maritime GHG emissions. Given the fact that the discussion regarding the implementation of some MBMs with maritime GHG-emission reduction potential is still carried out with the exception of EEDI (energy efficiency design index) and SEEMP (ship energy efficiency management plan), this paper's results present special significance, as they could be further analyzed and taken into account during the adoption of any future MBM for the reduction of maritime GHG emissions.展开更多
China has published a stricter emission standard for thermal power plants in order to help reduce the power industry's sulfur dioxide emissions by over six
[Objective] The study aimed at evaluating the ability to save energy and reduce CO2 emission in China's cement industry. [Method] Based on long-term energy alternative planning system software (LEAP), "LEAP of Ch...[Objective] The study aimed at evaluating the ability to save energy and reduce CO2 emission in China's cement industry. [Method] Based on long-term energy alternative planning system software (LEAP), "LEAP of China's cement industry" model was established to simulate energy conservation and emission reduction in China's cement industry from 2010 to 2040 in different technologic situations. E ResultJ To save ener- gy and reduce CO2 emissions, new dry process kiln has priority over other technologies or measures, followed by equipment enlargement, mechani- cal shaft kiln, power generation system based on waste heat, as well as high-efficiency and energy-saving grinding technology, and new prepara- tion technology. If all the advanced technologies and measures are adopted, energy consumption and C02 emissions can be reduced by about 40.76% and 42.97% respectively. [ Condusion] LEAP of model is suitable for analyzing energy saving and emission reducing in China's cement industry and other industrial fields.展开更多
Acetone,which is volatile,flammable,toxic,expen- sive and causing serious air pollution,is often used as extracting solvent in the production of powdery soy phospholipid.Recycling and reusing acetone is the key of red...Acetone,which is volatile,flammable,toxic,expen- sive and causing serious air pollution,is often used as extracting solvent in the production of powdery soy phospholipid.Recycling and reusing acetone is the key of reducing the cost of production. Therefore,saving energy and reducing emission when recycling acetone are the most important technologies during the production of phospholipid.On the basis of the productivity of powdery phospholipid being 2.4 t every day,43.2 t acetone is reused every 8 h and the total volume of acetone gas emitted is 450.75 m3 (about 901.5 kg).According to the current price of acetone,the lost money is about 7212 yuan RMB.展开更多
The energy consumption of iron ore sintering process is about 10%- 15%of the total of iron and steel industry.Therefore,it is of great significance to take effective measures to reduce the energy consumption in the ir...The energy consumption of iron ore sintering process is about 10%- 15%of the total of iron and steel industry.Therefore,it is of great significance to take effective measures to reduce the energy consumption in the iron ore sintering process to reduce the costs of sintering product and cut down the emissions of harmful gases,such as CO_2 and SO_2.In this study,the technology development of saving energy and reducing emission in iron ore sintering process was reviewed and discussed;some new directions and measures of saving energy were presented for the sintering process in the future.展开更多
Global political forums on climate have identified deforestation and forest degradation actions as the main sources of atmospheric emissions. Therefore, its reduction is basically the main international agenda. The ob...Global political forums on climate have identified deforestation and forest degradation actions as the main sources of atmospheric emissions. Therefore, its reduction is basically the main international agenda. The objectives of environmental policy seem to prevail conflicting, between the global, which aims to stabilize emissions with sequestration of forest carbon and local poverty reduction. REDD+ (Reducing Emissions from Deforestation and Forest Degradation) is considered cheap proposal for mitigation and adaptation to climate changes. Thus, Mozambique is preparing for accessing to forest carbon financing. The study analyzed interaction of policies and measures in the national and local strategy of REDD+ in Mozambique and resorted three methodological procedures, review of previous study, interviews and seminars, in a non-probabilistic sampling. Conflicting visions among nations hinder consensus on reducing emissions and REDD+ aims to replace the KP (Kyoto Protocol). National strategy of REDD+ should suggest measures and policies to reduce deforestation in key sectors contributing to emissions. Interviewees suggested technological approach (30%), agrarian reform (26%), institutional reform (21%) and decentralization (20%). Therefore, 77.3% supported technological use to increase production and productivity and for the forest sector, 86.4% supported forest concessions. They also highlighted conservation agriculture, SAFs (Agroforestry Systems), energy accessibility and mining licensing. However, REDD+ is being projected from the global to the local, but the debate must extrapolate negotiations restricted to government participation, as well as policy options and incentives to generate co-benefits that address local community priorities.展开更多
In order to deal with the global change and to reduce emission of greenhouse gas, a number of countries have strengthened studies on carbon sequestration in cropland. Carbon sequestration in cropland is not only an im...In order to deal with the global change and to reduce emission of greenhouse gas, a number of countries have strengthened studies on carbon sequestration in cropland. Carbon sequestration in cropland is not only an important component for the global carbon stock, but also is the most active part to sequestrate the carbon in soil from atmosphere. In this sense, it is of necessity and significance to strengthen the study on management of carbon sequestration in cropland. Based on the main factors affecting carbon cycle in agro-ecosystems, this paper summarizes the relevant management measures to strengthen the capacity of reducing emission of carbon and increasing the carbon sequestration in cropland, and evaluates the effects of these measures after being implemented at a regional extent.展开更多
The“3060”goal demonstrates China’s responsibility in actively responding to global climate,enhances China’s voice and influence in climate governance,and sets an example of energy conservation and emission reducti...The“3060”goal demonstrates China’s responsibility in actively responding to global climate,enhances China’s voice and influence in climate governance,and sets an example of energy conservation and emission reduction for developing countries.As the main institutions that educate people for the Party and the country,colleges and universities have the responsibility to explore the realization path of carbon peak and carbon neutralization against the new problems encountered in the practice of energy conservation and emission reduction in colleges and universities.In response to the national strategy and the action plan of the Ministry of Education,taking the carbon practice of China University of Geosciences(Beijing)as the starting point,this paper conducts benchmarking research on the path of carbon peak and carbon neutralization in universities through the ecological factor method,campus carbon footprint,and questionnaire analysis.展开更多
As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest research.Therefore,national governments are interested in developing forest-monitoring s...As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest research.Therefore,national governments are interested in developing forest-monitoring strategies using geospatial technology.Among statistical methods for mapping biomass,there is a nonparametric approach called k-nearest neighbor(kNN).We compared four variations of distance metrics of the kNN for the spatially-explicit estimation of aboveground biomass in a portion of the Mexican north border of the intertropical zone.Satellite derived,climatic,and topographic predictor variables were combined with the Mexican National Forest Inventory(NFI)data to accomplish the purpose.Performance of distance metrics applied into the kNN algorithm was evaluated using a cross validation leave-one-out technique.The results indicate that the Most Similar Neighbor(MSN)approach maximizes the correlation between predictor and response variables(r=0.9).Our results are in agreement with those reported in the literature.These findings confirm the predictive potential of the MSN approach for mapping forest variables at pixel level under the policy of Reducing Emission from Deforestation and Forest Degradation(REDD+).展开更多
We focused on key aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior ...We focused on key aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior conservation policies to take advantage of new climate change policies. Strengthening roles and technical capacity of national institutions for systematic biodiversity monitoring and carbon stock assessment is required in developing and least developed countries. Community participation needs careful analysis to ensure equitable ac- cess of particular social groups to local decision-making processes and to sustain optional livelihoods. The livelihood options around forest reserves or protected areas must be taken into account to enhance forest-based adaptation.展开更多
Within the past two decades or so, the asphalt paving industry has responded positively to increasing global concerns over shrinking natural resource reserves and worsening environmental conditions through the develop...Within the past two decades or so, the asphalt paving industry has responded positively to increasing global concerns over shrinking natural resource reserves and worsening environmental conditions through the development and deployment of warm-mix asphalt technologies. Such technologies make it possible to produce and place asphalt concrete at reduced temperatures compared to conventional hot-mix methods. Several studies have reported on the potential of warm-mix asphalt with regard to improved pavement performance, efficiency and environmental stewardship. This paper reviews several of those studies in the context of pavement sustainability. Overall, warm-mix asphalt provides substantial sustainability benefits similar to or, in some cases, better than conventional hot-mix asphalt. Sustainability benefits include lower energy use, reduced emissions, and potential for increased reclaimed asphalt pavement usage. Growth in utilization of warm-mix asphalt worldwide may, in the not-too-distant future, make the material the standard for asphalt paving. Regardless, there are concerns over some aspects of warm-mix asphalt such as lower resistance to fatigue cracking, rutting and potential water-susceptibility problems, particularly with mixes prepared with water-based technologies, which require further research to address.展开更多
Hujiatai Village, Xiong County, Hebei Province was nominated as the experimental unit of new countryside construction by Hebei Province in 2008. In order to make Hujiatai Village become a new countryside model with fr...Hujiatai Village, Xiong County, Hebei Province was nominated as the experimental unit of new countryside construction by Hebei Province in 2008. In order to make Hujiatai Village become a new countryside model with friendly ecological and environmental conditions, local energy resources should be considered. In this study, a mode of 'geothermal energy extraction-heat exchange-space heating-reinjection' was adopted to supply heat to resident houses in Hujiatai Village cooperating with a geothermal development entity based on the abundant geothermal resources, thereby constructing a clean, economic and autarkic new countryside energy system, which avoids utilization of fossil-energy, reduces emission of greenhouse gases and generation of solid coal cinder, protecting air and land environment, improving life quality of the people and building a typical model for Hebei Province and even for the whole country.展开更多
A concept of energy saving & efficiency improving from cold source for cogeneration steam turbine was discussed herein. A new type "NCB" cogeneration steam turbine was proposed,which could considerably i...A concept of energy saving & efficiency improving from cold source for cogeneration steam turbine was discussed herein. A new type "NCB" cogeneration steam turbine was proposed,which could considerably increase heat supply capacity,thermal efficiency and electric power. Taking 300 MW cogeneration steam turbine as an example,the results show that heat supply capacity reaches the maximum,i.e. increases by 30 %,thermal efficiency is improved by 12 %,and electric power is enhanced by 15 MW during peak heat load.展开更多
Kenya Airways announced its new carbon offset project in May,aiming to have guests directly take part in a carbon emissions reduction plan for environmental protection.Titus Naikuni,Managing Director
The aim of this study was to inventory plant biodiversity and to evaluate the carbon sequestration potential of the Misomuni forest massif.An inventory of all trees with diameter at breast height(dbh)≥10 cm measured ...The aim of this study was to inventory plant biodiversity and to evaluate the carbon sequestration potential of the Misomuni forest massif.An inventory of all trees with diameter at breast height(dbh)≥10 cm measured at 1.30 m height was performed.The aerial biomass(AGB)was used for estimating the stored CO2 and its carbon equivalent.88 plant species belonging to 71 genera and 32 families were inventoried.Fabaceae family displayed the highest number of species and genera.The highest basal area values were displayed by Scorodophloeus zenkeri(7.34±2.45 m2/ha),Brachystegia laurentii(5.82±1.94 m2/ha),Entandrophragma utile(5.28±1.94 m2/ha),Pentadesma butyracea(4.53±1.51 m2/ha).The highest values of stored carbon and their carbon equivalent were observed in Pentadesma butyracea(15.13±5.00 and 50.55±16.85 t/ha),Picralima nitida(7.02±2.34 and 23.66±7.88 t/ha),Strombosia tetandra(6.56±2.18 and 22.10±7.36 t/ha).The Misomuni forest massif is thus much floristically diversified and plays a significant role in the sequestration of CO2.The total AGB of the inventoried trees is 183.78±61.26 t/ha corresponding to stored carbon and carbon equivalent of 96.63±32.21 t/ha and 289.92±96.64 t/ha respectively.The protection of this ecosystem is highly needed for combatting climatic changes at local,national and regional scales and for the conservation biodiversity habitat.展开更多
New energy vehicles play a positive role in reducing carbon emissions.To improve the dynamic performance and durability of vehicle powertrain,the hybrid energy storage system of“fuel cell/power battery plus super cap...New energy vehicles play a positive role in reducing carbon emissions.To improve the dynamic performance and durability of vehicle powertrain,the hybrid energy storage system of“fuel cell/power battery plus super capacitor”is more used in new energy vehicles.Bidirectional DC–DC converters with wide voltage conversion range are essential for voltage matching and power decoupling between super capacitor and vehicle bus,helping to improve the low input voltage characteristics of super capacitors and realize the recovery of feedback energy.In recent years,the topologies of bidirectional converters have been widely investigated and optimized.Aiming to obtain bidirectional DC–DC converters with wide voltage conversion range suitable for hybrid energy storage system,a review of the research status of non-isolated converters based on impedance networks and isolated converters based on transformer are presented.Additionally,an evaluation system for bidirectional DC–DC topologies for hybrid energy storage system is constructed,providing a reference for designing bidirectional DC–DC converters.The performance of eight typical non-isolated converters and seven typical isolated converters are comprehensively evaluated by using this evaluation system.On this basis,issues about DC–DC converters for hybrid energy storage system are discussed,and some suggestions for the future research directions of DC–DC converters are proposed.The optimization of bidirectional DC–DC converters for hybrid energy storage system from the perspectives of wide bandgap device application,electromagnetic compatibility technology and converter fault diagnosis strategies is the main research direction.展开更多
文摘Climate change is widely recognized as the major environmental problem facing the globe today. One of the most urgent environmental problems facing shipping industry is the reduction of GHG (greenhouse gas) emissions from its operations. Given the growing concern of the international community on "the deep reduction of global GHG emissions", it cannot be expected that the non-regulation of maritime GHG emissions can further continue. This paper investigates the main challenges and threats of the development of two MBMs (market-based measures) for the reduction of GHG emissions from international shipping, i.e., the "global levy scheme on maritime GHG emissions" and the "maritime emission trading scheme". A SWOT (strengths weaknesses opportunities threat) analysis is used, in this survey, to evaluate the environmental effectiveness as well as the easiness of implementation of the two policy options. Moreover, we make apparent their strengths and weaknesses concerning abatement of maritime GHG emissions. Given the fact that the discussion regarding the implementation of some MBMs with maritime GHG-emission reduction potential is still carried out with the exception of EEDI (energy efficiency design index) and SEEMP (ship energy efficiency management plan), this paper's results present special significance, as they could be further analyzed and taken into account during the adoption of any future MBM for the reduction of maritime GHG emissions.
文摘China has published a stricter emission standard for thermal power plants in order to help reduce the power industry's sulfur dioxide emissions by over six
基金Supported by Special Project for Developing National Major Scientific Instruments and Equipments (2011YQ060111)Scientific Research Project of Environmental Protection in Commonweal Industry(201009032)
文摘[Objective] The study aimed at evaluating the ability to save energy and reduce CO2 emission in China's cement industry. [Method] Based on long-term energy alternative planning system software (LEAP), "LEAP of China's cement industry" model was established to simulate energy conservation and emission reduction in China's cement industry from 2010 to 2040 in different technologic situations. E ResultJ To save ener- gy and reduce CO2 emissions, new dry process kiln has priority over other technologies or measures, followed by equipment enlargement, mechani- cal shaft kiln, power generation system based on waste heat, as well as high-efficiency and energy-saving grinding technology, and new prepara- tion technology. If all the advanced technologies and measures are adopted, energy consumption and C02 emissions can be reduced by about 40.76% and 42.97% respectively. [ Condusion] LEAP of model is suitable for analyzing energy saving and emission reducing in China's cement industry and other industrial fields.
文摘Acetone,which is volatile,flammable,toxic,expen- sive and causing serious air pollution,is often used as extracting solvent in the production of powdery soy phospholipid.Recycling and reusing acetone is the key of reducing the cost of production. Therefore,saving energy and reducing emission when recycling acetone are the most important technologies during the production of phospholipid.On the basis of the productivity of powdery phospholipid being 2.4 t every day,43.2 t acetone is reused every 8 h and the total volume of acetone gas emitted is 450.75 m3 (about 901.5 kg).According to the current price of acetone,the lost money is about 7212 yuan RMB.
文摘The energy consumption of iron ore sintering process is about 10%- 15%of the total of iron and steel industry.Therefore,it is of great significance to take effective measures to reduce the energy consumption in the iron ore sintering process to reduce the costs of sintering product and cut down the emissions of harmful gases,such as CO_2 and SO_2.In this study,the technology development of saving energy and reducing emission in iron ore sintering process was reviewed and discussed;some new directions and measures of saving energy were presented for the sintering process in the future.
文摘Global political forums on climate have identified deforestation and forest degradation actions as the main sources of atmospheric emissions. Therefore, its reduction is basically the main international agenda. The objectives of environmental policy seem to prevail conflicting, between the global, which aims to stabilize emissions with sequestration of forest carbon and local poverty reduction. REDD+ (Reducing Emissions from Deforestation and Forest Degradation) is considered cheap proposal for mitigation and adaptation to climate changes. Thus, Mozambique is preparing for accessing to forest carbon financing. The study analyzed interaction of policies and measures in the national and local strategy of REDD+ in Mozambique and resorted three methodological procedures, review of previous study, interviews and seminars, in a non-probabilistic sampling. Conflicting visions among nations hinder consensus on reducing emissions and REDD+ aims to replace the KP (Kyoto Protocol). National strategy of REDD+ should suggest measures and policies to reduce deforestation in key sectors contributing to emissions. Interviewees suggested technological approach (30%), agrarian reform (26%), institutional reform (21%) and decentralization (20%). Therefore, 77.3% supported technological use to increase production and productivity and for the forest sector, 86.4% supported forest concessions. They also highlighted conservation agriculture, SAFs (Agroforestry Systems), energy accessibility and mining licensing. However, REDD+ is being projected from the global to the local, but the debate must extrapolate negotiations restricted to government participation, as well as policy options and incentives to generate co-benefits that address local community priorities.
基金Supported by National Natural Science Foundation of China(70873118)the Chinese Academy of Sciences (kzcx2-yw-305-2)the national key scientific and technological project(2006BAC08B03,2006BAC08B06,2008BAC43B01)~~
文摘In order to deal with the global change and to reduce emission of greenhouse gas, a number of countries have strengthened studies on carbon sequestration in cropland. Carbon sequestration in cropland is not only an important component for the global carbon stock, but also is the most active part to sequestrate the carbon in soil from atmosphere. In this sense, it is of necessity and significance to strengthen the study on management of carbon sequestration in cropland. Based on the main factors affecting carbon cycle in agro-ecosystems, this paper summarizes the relevant management measures to strengthen the capacity of reducing emission of carbon and increasing the carbon sequestration in cropland, and evaluates the effects of these measures after being implemented at a regional extent.
文摘The“3060”goal demonstrates China’s responsibility in actively responding to global climate,enhances China’s voice and influence in climate governance,and sets an example of energy conservation and emission reduction for developing countries.As the main institutions that educate people for the Party and the country,colleges and universities have the responsibility to explore the realization path of carbon peak and carbon neutralization against the new problems encountered in the practice of energy conservation and emission reduction in colleges and universities.In response to the national strategy and the action plan of the Ministry of Education,taking the carbon practice of China University of Geosciences(Beijing)as the starting point,this paper conducts benchmarking research on the path of carbon peak and carbon neutralization in universities through the ecological factor method,campus carbon footprint,and questionnaire analysis.
文摘As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest research.Therefore,national governments are interested in developing forest-monitoring strategies using geospatial technology.Among statistical methods for mapping biomass,there is a nonparametric approach called k-nearest neighbor(kNN).We compared four variations of distance metrics of the kNN for the spatially-explicit estimation of aboveground biomass in a portion of the Mexican north border of the intertropical zone.Satellite derived,climatic,and topographic predictor variables were combined with the Mexican National Forest Inventory(NFI)data to accomplish the purpose.Performance of distance metrics applied into the kNN algorithm was evaluated using a cross validation leave-one-out technique.The results indicate that the Most Similar Neighbor(MSN)approach maximizes the correlation between predictor and response variables(r=0.9).Our results are in agreement with those reported in the literature.These findings confirm the predictive potential of the MSN approach for mapping forest variables at pixel level under the policy of Reducing Emission from Deforestation and Forest Degradation(REDD+).
文摘We focused on key aspects of forest governance for biodiver- sity conservation in implementing new climate change policies. The national forest institutions must be adaptive to identify the existing pitfalls of prior conservation policies to take advantage of new climate change policies. Strengthening roles and technical capacity of national institutions for systematic biodiversity monitoring and carbon stock assessment is required in developing and least developed countries. Community participation needs careful analysis to ensure equitable ac- cess of particular social groups to local decision-making processes and to sustain optional livelihoods. The livelihood options around forest reserves or protected areas must be taken into account to enhance forest-based adaptation.
文摘Within the past two decades or so, the asphalt paving industry has responded positively to increasing global concerns over shrinking natural resource reserves and worsening environmental conditions through the development and deployment of warm-mix asphalt technologies. Such technologies make it possible to produce and place asphalt concrete at reduced temperatures compared to conventional hot-mix methods. Several studies have reported on the potential of warm-mix asphalt with regard to improved pavement performance, efficiency and environmental stewardship. This paper reviews several of those studies in the context of pavement sustainability. Overall, warm-mix asphalt provides substantial sustainability benefits similar to or, in some cases, better than conventional hot-mix asphalt. Sustainability benefits include lower energy use, reduced emissions, and potential for increased reclaimed asphalt pavement usage. Growth in utilization of warm-mix asphalt worldwide may, in the not-too-distant future, make the material the standard for asphalt paving. Regardless, there are concerns over some aspects of warm-mix asphalt such as lower resistance to fatigue cracking, rutting and potential water-susceptibility problems, particularly with mixes prepared with water-based technologies, which require further research to address.
基金Supported by the Major Program of Water Resources Exploration in Beijing City(Exploration and Assessment Project of Karst Water Resources in Beijing City
文摘Hujiatai Village, Xiong County, Hebei Province was nominated as the experimental unit of new countryside construction by Hebei Province in 2008. In order to make Hujiatai Village become a new countryside model with friendly ecological and environmental conditions, local energy resources should be considered. In this study, a mode of 'geothermal energy extraction-heat exchange-space heating-reinjection' was adopted to supply heat to resident houses in Hujiatai Village cooperating with a geothermal development entity based on the abundant geothermal resources, thereby constructing a clean, economic and autarkic new countryside energy system, which avoids utilization of fossil-energy, reduces emission of greenhouse gases and generation of solid coal cinder, protecting air and land environment, improving life quality of the people and building a typical model for Hebei Province and even for the whole country.
文摘A concept of energy saving & efficiency improving from cold source for cogeneration steam turbine was discussed herein. A new type "NCB" cogeneration steam turbine was proposed,which could considerably increase heat supply capacity,thermal efficiency and electric power. Taking 300 MW cogeneration steam turbine as an example,the results show that heat supply capacity reaches the maximum,i.e. increases by 30 %,thermal efficiency is improved by 12 %,and electric power is enhanced by 15 MW during peak heat load.
文摘Kenya Airways announced its new carbon offset project in May,aiming to have guests directly take part in a carbon emissions reduction plan for environmental protection.Titus Naikuni,Managing Director
文摘The aim of this study was to inventory plant biodiversity and to evaluate the carbon sequestration potential of the Misomuni forest massif.An inventory of all trees with diameter at breast height(dbh)≥10 cm measured at 1.30 m height was performed.The aerial biomass(AGB)was used for estimating the stored CO2 and its carbon equivalent.88 plant species belonging to 71 genera and 32 families were inventoried.Fabaceae family displayed the highest number of species and genera.The highest basal area values were displayed by Scorodophloeus zenkeri(7.34±2.45 m2/ha),Brachystegia laurentii(5.82±1.94 m2/ha),Entandrophragma utile(5.28±1.94 m2/ha),Pentadesma butyracea(4.53±1.51 m2/ha).The highest values of stored carbon and their carbon equivalent were observed in Pentadesma butyracea(15.13±5.00 and 50.55±16.85 t/ha),Picralima nitida(7.02±2.34 and 23.66±7.88 t/ha),Strombosia tetandra(6.56±2.18 and 22.10±7.36 t/ha).The Misomuni forest massif is thus much floristically diversified and plays a significant role in the sequestration of CO2.The total AGB of the inventoried trees is 183.78±61.26 t/ha corresponding to stored carbon and carbon equivalent of 96.63±32.21 t/ha and 289.92±96.64 t/ha respectively.The protection of this ecosystem is highly needed for combatting climatic changes at local,national and regional scales and for the conservation biodiversity habitat.
基金International Science&Technology Cooperation of China under 2019YFE0100200.
文摘New energy vehicles play a positive role in reducing carbon emissions.To improve the dynamic performance and durability of vehicle powertrain,the hybrid energy storage system of“fuel cell/power battery plus super capacitor”is more used in new energy vehicles.Bidirectional DC–DC converters with wide voltage conversion range are essential for voltage matching and power decoupling between super capacitor and vehicle bus,helping to improve the low input voltage characteristics of super capacitors and realize the recovery of feedback energy.In recent years,the topologies of bidirectional converters have been widely investigated and optimized.Aiming to obtain bidirectional DC–DC converters with wide voltage conversion range suitable for hybrid energy storage system,a review of the research status of non-isolated converters based on impedance networks and isolated converters based on transformer are presented.Additionally,an evaluation system for bidirectional DC–DC topologies for hybrid energy storage system is constructed,providing a reference for designing bidirectional DC–DC converters.The performance of eight typical non-isolated converters and seven typical isolated converters are comprehensively evaluated by using this evaluation system.On this basis,issues about DC–DC converters for hybrid energy storage system are discussed,and some suggestions for the future research directions of DC–DC converters are proposed.The optimization of bidirectional DC–DC converters for hybrid energy storage system from the perspectives of wide bandgap device application,electromagnetic compatibility technology and converter fault diagnosis strategies is the main research direction.