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1.
A decision-making model was constructed to assist remote Australian Indigenous communities select appropriate climate change mitigation programs. The Resilient Community and Livelihood Asset Integration Model (ReCLAIM) comprises six steps that focus on community assets and aspirations. The second of these steps is to determine the baseline carbon profiles of communities based on six sources of carbon emissions: materials, construction processes, stationary energy, transport, water systems and waste. The methodology employed an annualised lifecycle analysis of housing materials and construction, and an annual inventory of other emission sources. Profiles were calculated for two remote communities and compared to the Australian average and also average electricity consumption by remote communities in the Northern Territory.The results, expressed in tonnes of carbon dioxide equivalent (tCO2-e), showed that average household carbon profiles of the two communities (6.3 and 4.1 tCO2-e/capita/yr) were generally lower than the Australian average (7.3 tCO2-e/capita/yr). The stationary energy results revealed that infrastructure and building design could raise fuel consumption and costs, and therefore carbon emissions, despite modest lifestyles. The carbon emission categories differed between the two communities highlighting the need for an individualised approach to understanding the drivers of carbon emissions and mitigation responses.  相似文献   

2.
This paper examines policy and technology scenarios in California, emphasizing greenhouse gas (GHG) emissions in 2020 and 2030. Using CALGAPS, a new, validated model simulating GHG and criteria pollutant emissions in California from 2010 to 2050, four scenarios were developed: Committed Policies (S1), Uncommitted Policies (S2), Potential Policy and Technology Futures (S3), and Counterfactual (S0), which omits all GHG policies. Forty-nine individual policies were represented. For S1–S3, GHG emissions fall below the AB 32 policy 2020 target [427 million metric tons CO2 equivalent (MtCO2e) yr−1], indicating that committed policies may be sufficient to meet mandated reductions. In 2030, emissions span 211–428 MtCO2e yr−1, suggesting that policy choices made today can strongly affect outcomes over the next two decades. Long-term (2050) emissions were all well above the target set by Executive Order S-3-05 (85 MtCO2e yr−1); additional policies or technology development (beyond the study scope) are likely needed to achieve this objective. Cumulative emissions suggest a different outcome, however: due to early emissions reductions, S3 achieves lower cumulative emissions in 2050 than a pathway that linearly reduces emissions between 2020 and 2050 policy targets. Sensitivity analysis provided quantification of individual policy GHG emissions reduction benefits.  相似文献   

3.
《Energy Policy》2005,33(7):885-896
In this paper MARKAL-MACRO, an integrated energy-environment-economy model, is used to generate China’s reference scenario for future energy development and carbon emission through the year 2050. The results show that with great efforts on structure adjustment, energy efficiency improvement and energy substitution, China’s primary energy consumption is expected to be 4818 Mtce and carbon emission 2394 MtC by 2050 with annual decrease rate of 3% for the carbon intensity per GDP during the period 2000–2050. On the basis of this reference scenario, China’s marginal abatement cost curves of carbon for the year 2010, 2020 and 2030 are derived from the model, and the impacts of carbon emission abatement on GDP are also simulated. The results are compared with those from other sources. The research shows that the marginal abatement costs vary from 12US$/tC to 216US$/tC and the rates of GDP losses relative to reference range from 0.1% to 2.54% for the reduction rates between 5% and 45%. Both the marginal abatement costs and the rates of GDP losses further enlarge on condition that the maximum capacity of nuclear power is constrained to 240 GW or 160 GW by 2050. The paper concludes that China's costs of carbon abatement is rather high in case of carbon emissions are further cut beyond the reference scenario, and China's carbon abatement room is limited due to her coal-dominant energy resource characteristic. As economic development still remains the priority and per capita income as well as per capita carbon emission are far below the world average, it will be more realistic for China to make continuous contributions to combating global climate change by implementing sustainable development strategy domestically and playing an active role in the international carbon mitigation cooperation mechanisms rather than accepting a carbon emission ceiling.  相似文献   

4.
《Biomass & bioenergy》2006,30(4):296-303
Mitigating global climate change via CO2 emission control and taxation is likely to enhance the economic potential of bioenergy production and utilization. This study investigated the cost competitiveness of woody biomass for electricity production in the US under alternative CO2 emission reductions and taxes. We first simulated changes in the price of coal for electricity production due to CO2 emission reductions and taxation using a computable general equilibrium model. Then, the costs of electricity generation fueled by energy crops (hybrid poplar), logging residues, and coal were estimated using the capital budgeting method. Our results indicate that logging residues would be competitive with coal if emissions were taxed at about US$25 Mg−1 CO2, while an emission tax US$100 Mg−1 CO2 or higher would be needed for hybrid poplar plantations at a yield of 11.21 dry Mg ha−1 yr−1 (5 dry tons ac−1 yr−1) to compete with coal in electricity production. Reaching the CO2 emission targets committed under the Kyoto Protocol would only slightly increase the price of fossil fuels, generating little impact on the competitiveness of woody biomass. However, the price of coal used for electricity production would significantly increase if global CO2 emissions were curtailed by 20% or more. Logging residues would become a competitive fuel source for electricity production if current global CO2 emissions were cut by 20–30%. Hybrid poplar plantations would not be able to compete with coal until emissions were reduced by 40% or more.  相似文献   

5.
《Biomass & bioenergy》2007,31(9):601-607
In Australia, the Mandatory Renewable Energy Target (MRET) scheme, which targets a 9.5 TWh per annum increase in renewable electricity generation by 2010, is stimulating interest in bioenergy. Development of bioenergy projects may cause competition for biomass resources. For example, sawmill residues are an attractive feedstock for bioenergy, but are also utilised for particleboard manufacture. This study compares the greenhouse gas (GHG) mitigation impacts of alternative scenarios where sawmill residues are used either for generation of electricity or for manufacture of particleboard. The study considers a theoretical particleboard plant processing 100 kt feedstock of dry sawmill residues per annum. If the sawmill residues are used instead for bioenergy, and the particleboard plant utilises fresh plantation biomass, 205 kt CO2eq emissions are displaced. However, GHG emissions for particleboard manufacture increase by about 38 kt CO2eq, equivalent to 19% of the fossil fuel emissions displaced, due to the higher fossil fuel requirements to harvest, transport, chip and dry the green biomass. Also, plantation carbon stock declines by 147 kt CO2eq per year until a new equilibrium is reached after 30 years. This result is influenced particularly by the fossil fuel displaced, the relative efficiency of the fossil fuel and bioenergy plants, the moisture content of the sawmill residues, and the efficiency of the dryer in the particleboard plant.Under MRET, calculation of Renewable Energy Certificates is based solely on the quantity of power generated. This study illustrates that indirect consequences can reduce the GHG mitigation benefits of a bioenergy project. Increased emissions off-site, and loss of forest carbon stock, should be considered in calculating the net GHG mitigation benefit, and this should determine the credit earned by a bioenergy project.  相似文献   

6.
The present paper analyzes the CO2 emissions from mobile communications and portable wireless electronic devices in the Korea environment. The quantitative and qualitative contributions to CO2 emission reduction of the substitution of renewable energy for traditional electricity as the power supply in these devices are also investigated.Firstly, the national CO2 emission coefficient is temporarily estimated as 0.504 tCO2/MWh, which can be regarded as the basis for calculating CO2 emissions in mobile devices. The total annual CO2 emissions from mobile devices is calculated as approximately 1.4 million tons, comprising 0.3 million tCO2 for portable wireless electronic devices and 1.1 million tCO2 for electric equipment required for mobile communication service.If renewable energy sources are substituted for traditional electricity sources in the supply for mobile devices, solar cell and wind turbine systems can reduce CO2 emissions by about 87% and 97%, respectively. However, the use of fuel cell systems will only slightly reduce the CO2 emissions. However, the use of the direct methanol fuel cell system can release 8% more CO2 emissions than that emitted by using traditional electricity sources.  相似文献   

7.
《Biomass & bioenergy》2006,30(7):638-647
The use of firewood for domestic heating has the potential to reduce fossil-fuel use and associated CO2 emissions. The level of possible reductions depends upon the extent to which firewood off-sets the use of fossil fuels, the efficiency with which wood is burnt, and use of fossil fuels for collection and transport of firewood. Plantations grown for firewood also have a cost of emissions associated with their establishment. Applying the FullCAM model and additional calculations, these factors were examined for various management scenarios under three contrasting firewood production systems (native woodland, sustainably managed native forest, and newly established plantations) in low-medium rainfall (600–800 mm) regions of south-eastern Australia. Estimates of carbon dioxide emissions per unit of heat energy produced for all scenarios were lower than for non-renewable energy sources (which generally emit about 0.3–1.0 kg CO2 kWh−1). Amongst the scenarios, emissions were greatest when wood was periodically collected from dead wood in woodlands (0.11 kg CO2 kWh−1), and was much lower when obtained from harvest residues and dead wood in native forests (<0.03 kg CO2 kWh−1). When wood was obtained from plantations established on previously cleared agricultural land, use of firewood led to carbon sequestration equivalent to −0.06 kg CO2 kWh−1 for firewood obtained from a coppiced plantation, and −0.17 kg CO2 kWh−1 for firewood collected from thinnings, slash and other residue in a plantation grown for sawlog production. An uncertainty analysis, where inputs and assumptions were varied in relation to a plausible range of management practices, identified the most important influencing factors and an expected range in predicted net amount of CO2 emitted per unit of heat energy produced from burning firewood.  相似文献   

8.
Municipal solid waste (MSW) is a potential energy resource which can be incineration to energy. Furthermore, it can conserve more valuable fossil fuel and improve the environment by lessening Greenhouse Gas (GHG) emission and the amount of waste that must be landfilled. This paper highlights the MSW generation and characteristics for the city of Chongqing, the nation's fourth largest municipality after Beijing, Shanghai and Tianjin. At present the daily amount of MSW generated per person is about 0.85 kg; food waste accounts for about 53.7% of total MSW. MSW in Chongqing has higher moisture content and lower net caloric value, which is an obstruction for incineration. This paper examines the emission reductions potential for MSW incineration power plant in urban Chongqing. As a case study, emission reductions analysis and economic assessment was implemented for Tongxing MSW incineration power plant. The results show that with the power displacement potential at 235 060 MWh, Chongqing is expected to generate emission reductions as much as 815 862–827 969 tCO2 and net profit US$7.72 million per annum.  相似文献   

9.
We explored the production cost of energy crops at abandoned agricultural land and at rest land at a regional and a global level to the year 2050 using four different land-use scenarios. The estimations were based on grid cell data on the productivity of short-rotation crops on the available land over time and assumptions regarding the capital and the labour input required to reach these productivity levels. It was concluded that large amounts of grown biomass at abandoned agricultural land and rest land, 130–270 EJ yr?1 (about 40–70% of the present energy consumption) may be produced at costs below $2 GJ?1 by 2050 (present lower limit of cost of coal). Interesting regions because of their low production cost and significant potentials are the Former USSR, Oceania, Eastern and Western Africa and East Asia. Such low costs presume significant land productivity improvements over time and cost reductions due to learning and capital-labour substitution. An assessment of biomass fuel cost, using the primary biomass energy costs, showed that the future costs of biomass liquid fuels may be in the same order of the present diesel production costs, although this may change in the long term. Biomass-derived electricity costs are at present slightly higher than electricity baseload costs and may directly compete with estimated future production costs of fossil fuel electricity with CO2 sequestration. The present world electricity consumption of around 20 PWh yr?1 may be generated in 2050 at costs below $45 MWh?1 in A1 and B1 and below $55 MWh?1 in A2 and B2. At costs of $60 MWh?1, about 18 (A2) to 53 (A1) PWh yr?1 can be produced.  相似文献   

10.
Rob Bailis 《Biomass & bioenergy》2009,33(11):1491-1502
Current carbon accounting methodologies do not accommodate activities that involve emissions reductions from both land-use change and energy production. This paper analyzes the climate change mitigation potential of charcoal production in East Africa by examining the impact of changing both land management and technology. Current production in a major charcoal producing region of Kenya where charcoal is made as a by-product of land clearance for commercial grain production is modeled as the “business-as-usual” scenario. Alternative production systems are proposed based on coppice management of native or exotic trees. Improved kilns are also considered. Changes in aboveground, belowground, and soil carbon are modeled and two distinct baseline assessments are analyzed: one is based on a fixed area of land and one is based on the quantity of non-renewable fuel that is displaced by project activities. The magnitude of carbon emissions reductions varies depending on land management as well as the choice of carbonization technology. However, these variations are smaller than the variations arising from the choice of baseline methodology. The fixed-land baseline yields annualized carbon emission reductions equivalent to 0.5–2.8 tons per year (t y?1) with no change in production technology and 0.7–3.5 t y?1 with improved kilns. In contrast, the baseline defined by the quantity of displaced non-renewable fuel is 2–6 times larger, yielding carbon emissions reductions of 1.4–12.9 t y?1 with no change in production technology and 3.2–20.4 t y?1 with improved kilns. The results demonstrate the choice of baseline, often a political rather than scientific decision, is critical in assessing carbon emissions reductions.  相似文献   

11.
This paper examined promotion programs and implementing regulations that provide a framework for the application of energy and agricultural policies for the local energy crops cultivation by the reactivation of fallow land (about 100,000 ha) and their utilizations in the bioenergy production in Taiwan. The contents were thus addressed on current energy supply and biomass energy production, estimation of carbon dioxide (CO2) emissions from energy use (consumption) using the Reference Approach of the Intergovernmental Panel on Climate Change (IPCC) method, national energy goal in biomass energy supply in the near future, and government policies and measures for encouraging bioenergy production and consumption. For the promotion of biofuels, the incentive programs were initiated in the period of 2006–2011. The potential benefits of the program include the upgrade of industrial investment in the bioenergy plants, the reactivation of fallow land (about 100,000 ha), the mitigation of CO2 emissions, and so on. Concerning the utilization of napier grass (a potential energy grass) as biomass energy (electricity generation) for co-firing, its impacts on ambient air quality and non-CO2 greenhouse gases (i.e., CH4 and N2O) emissions were also discussed in the paper.  相似文献   

12.
The successful deployment of a hydrogen delivery (transmission and distribution) infrastructure will be critical for the widespread use of hydrogen. Estimates based on three scenarios that vary in the degree of hydrogen penetration in the European energy system indicate that between 1 and 4 million km of distribution pipelines, and up to 35 000 km of high-pressure transmission and 400 000 km of medium pressure sub-transmission pipelines may be needed by 2050. A truck fleet for the supply of liquefied hydrogen may reach the size of 3000–8000 vehicles. The cumulative capital necessary to build this infrastructure by 2050 may range between 700 and 2200 thousand million euros for the most optimistic scenario and is significantly lower for the other scenarios. Most of this will be needed for the development of the distribution network. These costs however represent a relatively small fraction (7.5–22%) of the annual gross value added of the energy sector.  相似文献   

13.
《Biomass & bioenergy》2005,28(5):454-474
In the face of climate change that may result from greenhouse gas (GHG) emissions, the scarcity of agricultural land and limited competitiveness of biomass energy on the market, it is desirable to increase the performance of bioenergy systems. Multi-product crops, i.e. using a crop partially for energy and partially for material purposes can possibly create additional incomes as well as additional GHG emission reductions. In this study, the performance of several multi-product crop systems is compared to energy crop systems, focused on the costs of primary biomass fuel costs and GHG emission reductions per hectare of biomass production. The sensitivity of the results is studied by means of a Monte-Carlo analysis. The multi-product crops studied are wheat, hemp and poplar in the Netherlands and Poland. GHG emission reductions of these multi-product crop systems are found to be between 0.2 and 2.4 Mg CO2eq/(ha yr) in Poland and 0.9 and 7.8 Mg CO2eq/(ha yr) in the Netherlands, while primary biomass fuel costs range from −4.1 to −1.7 €/GJ in the Netherlands and from 0.1 to 9.8 €/GJ in Poland. Results show that the economic attractiveness of multi-product crops depends strongly on material market prices, crop production costs and crop yields. Net annual GHG emission reductions per hectare are influenced strongly by the specific GHG emission reduction of material use, reference energy systems and GHG emissions of crop production. Multi-product use of crops can significantly decrease primary biomass fuel costs. However, this does not apply in general, but depends on the kind of crops and material uses. For the examples analysed here, net annual GHG emission reductions per hectare are not lowered by multi-product use of crops. Consequently, multi-product crops are not for granted an option to increase the performance of bioenergy systems. Further research on the feasibility of large-scale multi-product crop systems and their impact on land and material markets is desirable.  相似文献   

14.
Municipal residue biomass (MRB) in the municipal solid waste (MSW) stream is a potential year-round bioenergy feedstock. A method is developed to estimate the amount of residue biomass generated by the end-user at the scale of a country using a throughput approach. Given the trade balance of food and forestry products, the amount of MRB generated is calculated by estimating product lifetimes, discard rates, rates of access to MSW collection services, and biomass recovery rates. A wet tonne of MRB could be converted into about 8 GJ of energy and 640 kg of carbon dioxide (CO2) emissions, or buried in a landfill where it would decompose into 1800 kg of CO2 equivalent (in terms of global warming potential) methane (CH4) and CO2 emissions. It is estimated that approximately 1.5 Gt y?1 of MRB are currently collected worldwide. The energy content of this biomass is approximately 12 EJ, but only a fraction is currently utilized. An integrated assessment model is used to project future MRB generation and its utilization for energy, with and without a hypothetical climate policy to stabilize atmospheric CO2 concentrations. Given an anticipated price for biomass energy (and carbon under a policy scenario), by the end of the century, it is projected that nearly 60% of global MRB would be converted to about 8 EJ y?1 of energy in a reference scenario, and nearly all of global MRB would be converted into 16 EJ y?1 of energy by the end of the century under a climate policy scenario.  相似文献   

15.
This paper analyses the potential of renewable energy for power generation and its energy, environmental and economic implications in Pakistan, using a bottom up type of long term energy system based on the MARKAL framework. The results show that under a highly optimistic renewable portfolio standard (RPS) of 80%, fossil fuel consumption in 2050 would be reduced from 4660 PJ to 306 PJ, and the GHG emissions would decrease from 489 million tons to 27 million tons. Nevertheless, price of the electricity generation will increase significantly from US$ 47/MWh under current circumstances (in the base case) to US$ 86/MWh under RPS80. However the effects on import dependency, energy-mix diversity, per unit price of electricity generation and cost of imported fuels indicate that, it may not be desirable to go beyond RPS50. Under RPS50 in 2050, fuel consumption of the power sector would reduce from 21% under the base case to 9% of total fossil fuels supplied to the country. It will decrease not only GHG emission to 170 million tons but also will reduce import dependency from 73% under the base case to 21% and improve energy diversity mix with small increase in price of electricity generation (from US$ 47/MWh under the base case to US$ 59/MWh under RPS 50).  相似文献   

16.
The transport sector of a country is the backbone driving the economy forward. Thailand’s land transport sector is modelled using the AIM/Enduse, which is a recursive dynamic optimization model, based on bottom-up modelling principle. The travel demand is divided into two major categories which are passenger travel and freight travel. The objective of this paper is to analyse the mitigation possible through low carbon society (LCS) measures and emission tax (ET). Two scenario clusters are devised along with the BAU case. The LCS scenario cluster has three designed scenarios which are LCS-L, LCS-M and LCS-H. The emission tax (ET) cluster has four scenarios, where the taxes of 50, 100, 200 and 500 USD/t-CO2 are implemented. Along with this the marginal abatement costs (MAC) of the counter-measures (CMs) and the co-benefits in terms of energy security, productivity and air pollutant mitigation are also assessed. Results show that LCS scenarios are possible of mitigating up to 1230 Mt-CO2 cumulatively, from 2010 to 2050. In terms of MACs, new vehicles play a pivotal role, along with hybrid vehicles. The Average Abatement Cost (AAC) assessment shows that the AAC of LCS-H scenario is in the order of 100 USD/t-CO2. All the LCS and ET scenarios show an enhancement in energy security and also a threefold increase in productivity. There is distinct mitigation in terms of air pollutants from the transport sector as well.  相似文献   

17.
Much of China's cement industry still uses outdated kilns and other inefficient technologies, which are obstacles to improving energy efficiency. Huge improvements in energy consumption intensity can be made by improving this technology. To evaluate the potential for energy-saving and CO2 emissions reduction in China's cement industry between 2010 and 2020, a model was developed based on the Asian-Pacific Integrated Model (AIM). Three scenarios (S1, S2 and S3) were developed to describe future technology policy measures in relation to the development of the cement industry. Results show that scenario S3 would realize the potential for CO2 emissions mitigation of 361.0 million tons, accounting for 25.24% of the predicted emissions, with an additional energy saving potential of 39.0 million tons of coal equivalent by 2020. Technology promotion and industrial structure adjustment are the main measures that can lead to energy savings. Structural adjustment is the most important approach to reduce the CO2 emissions from the cement industry; the resulting potential for CO2 emissions reduction will be increasingly large, even exceeding 50% after 2016.  相似文献   

18.
The objective of the present work is to validate the hydrogen energy roadmap of Japan by analyzing the market penetration of fuel cell vehicles (FCVs) and the effects of a carbon tax using an energy system model of Japan based on MARKAL. The results of the analysis show that a hydrogen FCV would not be cost competitive until 2050 without a more severe carbon tax than the government's planned 2400 JPY/t-C carbon tax. However, as the carbon tax rate increases, instead of conventional vehicles including the gasoline hybrid electric vehicle, hydrogen FCVs gain market penetration earlier and more. By assuming a more severe carbon tax rate, such as 10 000 JPY/t-C, the market share of hydrogen FCVs approaches the governmental goal. This suggests that cheaper vehicle cost and hydrogen cost than those targeted in the roadmap should be attained or subsidies to hydrogen FCV and hydrogen refueling station will be necessary for achieving the goal of earlier market penetration.  相似文献   

19.
We assessed options for mitigating greenhouse gas emissions from electricity generation in the US Great Lakes States, a region heavily dependent on coal-fired power plants. A proposed 600 MW power plant in northern Lower Michigan, USA provided context for our evaluation. Options to offset fossil CO2 emissions by 20% included biomass fuel substitution from (1) forest residuals, (2) short-rotation woody crops, or (3) switchgrass; (4) biologic sequestration in forest plantations; and (5) geologic sequestration using CO2 capture. Review of timber product output data, land cover data, and expected energy crop productivity on idle agriculture land within 120 km of the plant revealed that biomass from forestry residuals has the potential to offset 6% and from energy crops 27% of the annual fossil fuel requirement. Furthermore, annual forest harvest in the region is only 26% of growth and the surplus represents a large opportunity for forest products and bioenergy applications. We used Life Cycle Assessment (LCA) to compare mitigation options, using fossil energy demand and greenhouse gas emissions per unit electricity generation as criteria. LCA results revealed that co-firing with forestry residuals is the most attractive option and geologic sequestration is the least attractive option, based on the two criteria. Biologic sequestration is intermediate but likely infeasible because of very large land area requirements. Our study revealed that biomass feedstock potentials from land and forest resources are not limiting mitigation activities, but the most practical approach is likely a combination of options that optimize additional social, environmental and economic criteria.  相似文献   

20.
What are the feasibility, costs, and environmental implications of large-scale bioenegry? We investigate this question by developing a detailed representation of bioenergy in a global economy-wide model. We develop a scenario with a global carbon dioxide price, applied to all anthropogenic emissions except those from land use change, that rises from $25 per metric ton in 2015 to $99 in 2050. This creates market conditions favorable to biomass energy, resulting in global non-traditional bioenergy production of ~ 150 exajoules (EJ) in 2050. By comparison, in 2010, global energy production was primarily from coal (138 EJ), oil (171 EJ), and gas (106 EJ). With this policy, 2050 emissions are 42% less in our Base Policy case than our Reference case, although extending the scope of the carbon price to include emissions from land use change would reduce 2050 emissions by 52% relative to the same baseline. Our results from various policy scenarios show that lignocellulosic (LC) ethanol may become the major form of bioenergy, if its production costs fall by amounts predicted in a recent survey and ethanol blending constraints disappear by 2030; however, if its costs remain higher than expected or the ethanol blend wall continues to bind, bioelectricity and bioheat may prevail. Higher LC ethanol costs may also result in the expanded production of first-generation biofuels (ethanol from sugarcane and corn) so that they remain in the fuel mix through 2050. Deforestation occurs if emissions from land use change are not priced, although the availability of biomass residues and improvements in crop yields and conversion efficiencies mitigate pressure on land markets. As regions are linked via international agricultural markets, irrespective of the location of bioenergy production, natural forest decreases are largest in regions with the lowest barriers to deforestation. In 2050, the combination of carbon price and bioenergy production increases food prices by 3.2%–5.2%, with bioenergy accounting for 1.3%–3.5%.  相似文献   

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