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71.
Ni was effectively recovered from spent electroless nickel (EN) plating baths by forming a nano-nickel coated activated carbon composite. With the aid of ultrasonication, melamine- formaldehyde-tetraoxalyl-ethylenediamine chelating resins were grafted on activated carbon (MFT/AG). PdC12 sol was adsorbed on MFT/AC, which was then immersed in spent electroless nickel plating bath; then nano-nickel could be reduced by ascorbic acid to form a nano-nickel coating on the activated carbon composite (Ni/AC) in situ. The materials present were carefully examined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and electro- chemistry techniques. The resins were well distributed on the inside and outside surfaces of activated carbon with a size of 120 ± 30 nm in MFT/AC, and a great deal of nano-nickel particles were evenly deposited with a size of 3.8 ± 1.1 nm in Ni/MFT. Moreover, Ni/AC was successfully used as a catalyst for ultrasonic degradation of 2.6-dichloronhenol.  相似文献   
72.
Multi-walled carbon nanotube(MWCNT) sheet was fabricated from a drawable MWCNT forest and then deposited on poly(methyl methacrylate) film. The film was further coated with a natural antimicrobial peptide nisin. We studied the effects of nisin coating on the attachment of Bacillus anthracis spores, the germination of attached spores, and the subsequent biofilm formation from attached spores. It was found that the strong adsorptivity and the super hydrophobicity of MWCNTs provided an ideal platform for nisin coating. Nisin coating on MWCNT sheets decreased surface hydrophobicity, reduced spore attachment, and reduced the germination of attached spores by 3.5 fold, and further inhibited the subsequent biofilm formation by 94.6% compared to that on uncoated MWCNT sheet. Nisin also changed the morphology of vegetative cells in the formed biofilm.The results of this study demonstrated that the anti-adhesion and antimicrobial effect of nisin in combination with the physical properties of carbon nanotubes had the potential in producing effective anti-biofilm formation surfaces.  相似文献   
73.
随着应对全球气候变化进程的不断推进,“低碳经济”已逐渐成为世界各国实现经济社会可持续发展的必由之路.京津冀及周边地区社会经济发展较不平衡,整体推进低碳经济发展存在较大的困难,为有效促进低碳经济发展的策略选择,本文通过构建低碳经济发展水平评价指标体系,对京津冀及周边地区的低碳经济发展状况进行评价.结果显示,京津冀及周边地区低碳经济发展水平差异较大:北京低碳经济水平相对较高,其他地区距离低碳经济发展水平尚有较大差距.由此,京津冀及周边地区应根据地区经济发展特点及其低碳经济发展状况,采取不同的低碳发展策略选择,以有效推进低碳经济发展模式的顺利转型.  相似文献   
74.
为更好地推动崇明低碳生态岛的建设,在应用以自下而上的部门法为基础的区域范围温室气体排放评估核算方法,全面核算崇明岛能源消费及温室气体排放现状的基础上,应用LEAP模型,通过情景分析预测崇明岛中长期能源消费需求以及温室气体排放水平,并进一步应用对数平均指数法(LMDI)对影响崇明岛未来温室气体排放的主要因素进行了定量分析。研究表明:参考情景下,崇明岛能源消费总量从2010年的101万吨标煤增加到2050年的533万吨标煤,净碳足迹从2010年的238万吨CO2e增加到2050年的579万吨CO2e。崇明岛能源消费需求和碳排放增加的主要驱动因素是未来的经济发展、人口增长和生活水平的提高,但是通过一系列的优化,尤其是能源结构的变化和能耗强度的下降,减排情景下,崇明岛能源消费总量有可能在2039年左右达到峰值,并有望在2050年左右实现"零碳岛"的长期发展目标。结合定量分析的结论,进一步提出了实现崇明岛低碳发展中长期目标的可能性和重点发展领域。  相似文献   
75.
中国省际碳排放效率的空间计量   总被引:3,自引:0,他引:3  
本文基于至强有效前沿的最小距离法测算了我国1998-2011年的省际CO2排放效率,这种方法的优点是效率达到生产前沿后在投入或产出方面所做出的改动最小。然后在此基础上分析了我国省际碳排放效率的区域差异性以及空间相关性,最后运用1998-2011年我国30个省份的面板数据,建立空间面板数据模型,对我国碳排放效率的影响因素进行了实证研究。研究结果表明:样本期内,我国省际碳排放效率表现出较大的省际差异性,东部沿海省份的平均碳排放效率显著高于内陆省份。分地区看,东部地区的碳排放效率走势相对平稳,全国及中西部地区的碳排放效率则呈现出"U"型曲线的走势,并且东部地区的碳排放效率明显要高于中西部地区;空间自相关Moran’s I检验显示,省际碳排放效率在空间上存在着显著的空间自相关性,具有明显的集群趋势,而空间LISA图则表明省际碳排放效率不仅具有空间依赖性的特征,同时也有空间异质性的表现;经济规模、工业结构和能源消费结构对碳排放效率造成了较大的负面影响,对外开放、企业所有制结构以及政府干预对碳排放效率有正向影响,而产业结构对碳排放效率的影响则不显著。因此,对于将来中国提高碳排放效率工作的重点应该是实现经济增长模式由粗放型向集约型的转变,着重调整工业结构和能源消费结构,同时进一步提升对外开放的质量,加强政府的碳减排工作力度。  相似文献   
76.
"十一五"期间,中国对COD和SO2两种污染物开展总量减排工作,预期指标超额完成。"十一五"期间构建起来的总量减排数据核算体系为中央政府提供了相对准确的减排数据,是减排取得成功的基础。本文通过研究减排数据核算体系来对总量减排的成功进行制度性解释。本文采用文本分析和实地调研的方法,描述了中国减排数据核算体系的组织机构及其基本职责,整理出了自下而上的数据生成、流动机制和自上而下的数据核查、反馈机制,归纳出总量减排数据核算体系相较于传统环境统计的基本特征:一是设立了区域督查中心和各级总量控制部门等专门的组织机构;二是数据的双向流动机制,中央拥有对减排数据的审核权和最终确定权,并且会将正式确定后的数据逐级反馈给地方政府并应用于上级政府对下级政府的行政考核当中去;三是在数据核算中采用环境监测数据,并因此进行了全国范围的环境监测能力建设;四是减排工作全过程数据核算。这些新特征使得中国减排数据核算体系得以提升减排数据质量,对地方政府可能的违规行为进行约束;将减排绩效与地方政府考核相结合,通过政治激励促进地方政府开展减排工作;加强地方政府环境监管能力,保障减排工作的开展和完成。但现有数据核算体系仍然存在监测数据利用不到位而导致行政成本较高、减排量核算细则"一刀切"导致政策公平性缺失等亟需改进完善的问题。  相似文献   
77.
低碳经济的政策分析,通常囿于单一国家层面的局部均衡结果,较少考虑到全球整体行动的外部影响,但从《联合国气候变化框架公约》建立以来的全球一致减排行动,却产生了一些意料之外的负面效果。本文通过梳理《京都议定书》签订以来,全球低碳经济合作中遇到的新挑战,以及碳交易市场的建设状况,采用制度分析与新古典框架下的市场均衡分析方法,讨论了全球一致减排行动所触发的"绿色悖论"问题。研究发现,造成"绿色悖论"的主要原因,一方面是由于国际合作存在制度设计上的缺陷,《京都议定书》及其关键性的附件一,将重点放在如何限制发达工业国的减排设计上,但却忽视了发展中国家在协议期内有可能出现的增排问题,以及发达国家向发展中国家污染转移的碳泄漏等问题;另一方面,当对不可再生资源的使用征税、以及对其替代品进行补贴时,将会导致在当前期对于化石能源的加速开采,并可能导致对同时期的化石燃料替代品的其他可再生资源的开采速度也大幅度加快,造成了在双重加速开采下的全球绿色福利损失以及CO2排放量的急剧升高,化石能源消费与温室气体排放面临到比协议签署前更为严峻,甚至与全球合作减排框架的设计初衷相悖的结果。研究结果表明,非全局性的减排公约和分阶段的减排政策,是造成"绿色悖论"现象的重要条件,缺少了大量发展中国家和一些重要工业国的缔约,使得负面的环境外部性难以克服;同时,减排任务和责任有所区别的分阶段设计,会把在未来行动期内可预见到的更高地化石能源使用成本转嫁到当前的行动期,造成短时间内资源与环境的迅速破坏。但本文的研究也表明,社会最优经济与对可再生能源进行补贴是克服"绿色悖论"现象的两条可行路径,且需要有与其相匹配的政府政策的支持。由此,本文的主要政策建议是,中国需要加强在国际气候公约中的影响力,提升自身话语权;以碳税政策作为发展低碳经济制度设计的主要政策工具;加快技术进步、提高能源使用效率,对于可再生能源研发进行补贴;根据国情不断优化碳税税率,并适时调整与其相匹配的新能源补贴等相关政策。  相似文献   
78.
Foreign trade drives China’s growth,but as the trade scale continues to expand,the carbon emissions also increase quickly.Based on the industry panel data from 1996 to 2010,this paper calculates carbon emissions of 27manufacturing industries.According to the intensity of carbon emissions,this paper divides the manufacturing sectors into low carbon and high carbon manufacturing industry and then analyzes the carbon emission trends.Next,the paper uses the feasible generalized least square regression to verify the existence of environmental Kuznets curve(EKC)of the manufacturing industry’s carbon.In order to investigate the carbon leakage problem,the regression also includes the interaction term between trade and industrial value added.Our findings are as follows:the carbon emissions of the whole manufacturing industry and low carbon manufacturing industry accord with the EKC curve,but have a linear relationship with the high carbon manufacturing industry;trade reduces the carbon emissions of the whole manufacturing industry and low carbon manufacturing industry,but it increases those of the high carbon manufacturing industry;for the whole manufacturing industry and low carbon manufacturing industry,there is no carbon leakage,but it exists in the high carbon manufacturing industry.On the whole,pollution haven hypothesis does not hold up in China,and China does not need to limit industry foreign trade to reduce the emission of CO2.But the manufacturing industry will still be the main engine of the economic growth,and therefore our country should make an effective low-carbon policy,introduce advanced technology,increase R&D investment into lowcarbon technologies,and upgrade and transform the original equipment to change the backward mode of production.  相似文献   
79.
International cooperation to address climate change now stands at a crossroads.With a new international regime for emissions reduction established by the Durban Platform, "New Climate Economics(NCE)" has become a research hotspot.The need for urgent action to combat climate change has prompted discussion on reforms of economic growth patterns and the energy system.The industrial civilization,therefore,now faces a transition towards a new pathway for ecological sustainability.NCE explores new economic concepts,theories,and analytical methods to design a balanced pathway for sustainable growth and emission reduction.Instead of getting trapped in discussions on allocation of emission reduction responsibilities and obligations among countries,NCE pays more attention to developing win-win multilateral cooperation mechanisms that facilitate collaborative RD and knowledge sharing.In addition,NCE studies incentives for low-carbon transition,turning carbon emission reduction into a domestic need for countries to increase their international competitiveness.To achieve the 2°C target,most countries around the world face challenges of insufficient emission allowances to cover expected emissions associated with their projected economic growth.As carbon emissions rights becomes an increasingly scarce resource,increasing the carbon productivity of the economy turns to be the critical path to address the dilemma of green or growth.NCE studies the historical evolution of carbon productivity for countries at different development stages as well as ways to enhance such carbon productivity.This type of study provides invaluable lessons for emerging economies to reach their own emission peaks without losing the momentum of growth.Replacing fossil fuels with new and renewable energy has proven to be an inevitable choice for reshaping the energy system and addressing climate change- it has already become a global trend.NCE studies incentives for new energy technology innovation and deployment provided by carbon pricing,and sheds light on the co-benefits of climate change mitigation,such as resource conservation,environmental protection,and energy security.The role of carbon pricing in promoting intemational RD cooperation and technical transfer will also be studied.The shift in consumption patterns is another key factor enabling a low-carbon transformation.Therefore,NCE also explores the theoretical work on new values of wealth,welfare and consumption,new lifestyles in the context of ecological civilization,concepts and implementation of low-carbon urban planning in developing countries,and the impacts of consumption pattern changes on social development,material production,and urban infrastructure construction.  相似文献   
80.
The establishment of a global multi-regional carbon market is considered to be a cost effective approach to facilitate global emission abatement and has been widely concerned.The ongoing planned linkage between the European Union’s carbon market and a new emission trading system in Australia in 2015 would be an important attempt to the practice of building up an international carbon market across different regions.To understand the abatement effect of such a global carbon market and to study its energy and economic impact on different market participants,this article adopts a global dynamic computable general equilibrium model with a detailed representation of the interactions between energy and economic systems.Our model includes 20 economic sectors and 19 regions,and describes in detail 17 energy technologies.Bundled with fossil fuel consumptions,the emission permits are considered to be essential inputs in each of the production and consumption activities in the economic system to simulate global carbon market policies.Carbon emission permits are endogenously set in the model,and can be traded between sectors and regions.Considering the current development of the global carbon market,this study takes 2020 as the study period.Four scenarios(reference scenario,independent carbon market scenario,Europe Union(EUh-Australia scenario,and China-EU-Australia scenario) are designed to evaluate the impact of the global carbon market involving China,the EU,and Australia.We find that the carbon price in the three countries varies a lot,from $32/tCO2 in Australia,to $17.5/tCO2 in the EU,and to $10/tCO2 in China.Though the relative emission reduction(3%) in China is lower than that in the EU(9%) and Australia(18%),the absolute emission reduction in China is far greater than that in the EU and Australia.When China is included in the carbon market,which already includes the EU and Australia,the prevailing global carbon price falls from $22 per ton carbon dioxide(CO2) to $12/tCO2,due to the relatively lower abatement cost in China.Seventy-one percent of the EU’s and eighty-one percent of Australia’s domestic reduction burden would be transferred to China,increasing 0.03%of the EU’s and 0.06%of Australia’s welfare.The emission constraint improves the energy efficiency of China’s industry sector by 1.4%,reduces coal consumption by3.3%,and increases clean energy by 3.5%.  相似文献   
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