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591.
Carbon leakage is central to the discussion on how to mitigate climate change. The current carbon leakage literature focuses largely on industrial production, and less attention has been given to carbon leakage from the electricity sector (the largest source of carbon emissions in China). Moreover, very few studies have examined in detail electricity regulation in the Chinese national emissions trading system (which leads, for example, to double counting) or addressed its implications for potential linkage between the EU and Chinese emissions trading systems (ETSs). This article seeks to fill this gap by analysing the problem of ‘carbon leakage’ from the electricity sector under the China ETS. Specifically, a Law & Economics approach is applied to scrutinize legal documents on electricity/carbon regulation and examine the economic incentive structures of stakeholders in the inter-/intra-regional electricity markets. Two forms of ‘electricity carbon leakage’ are identified and further supported by legal evidence and practical cases. Moreover, the article assesses the environmental and economic implications for the EU of potential linkage between the world’s two largest ETSs. In response, policy suggestions are proposed to address electricity carbon leakage, differentiating leakage according to its sources.

Key policy insights

  • Electricity carbon leakage in China remains a serious issue that has yet to receive sufficient attention.

  • Such leakage arises from the current electricity/carbon regulatory framework in China and jeopardizes mitigation efforts.

  • With the US retreat on climate efforts, evidence suggests that EU officials are looking to China and expect an expanded carbon market to reinforce EU global climate leadership.

  • Given that the Chinese ETS will be twice the size of the EU ETS, a small amount of carbon leakage in China could have significant repercussions. Electricity carbon leakage should thus be considered in any future EU–China linking negotiations.

  相似文献   
592.
李鹏飞  周晓军 《海洋工程》2015,29(6):875-890
Subsea tunnel lining structures should be designed to sustain the loads transmitted from surrounding ground and groundwater during excavation. Extremely high pore-water pressure reduces the effective strength of the country rock that surrounds a tunnel, thereby lowering the arching effect and stratum stability of the structure. In this paper, the mechanical behavior and shape optimization of the lining structure for the Xiang’an tunnel excavated in weathered slots are examined. Eight cross sections with different geometric parameters are adopted to study the mechanical behavior and shape optimization of the lining structure. The hyperstatic reaction method is used through finite element analysis software ANSYS. The mechanical behavior of the lining structure is evidently affected by the geometric parameters of cross- sectional shape. The minimum safety factor of the lining structure elements is set to be the objective function. The efficient tunnel shape to maximize the minimum safety factor is identified. The minimum safety factor increases significantly after optimization. The optimized cross section significantly improves the mechanical characteristics of the lining structure and effectively reduces its deformation. Force analyses of optimization process and program are conducted parametrically so that the method can be applied to the optimization design of other similar structures. The results obtained from this study enhance our understanding of the mechanical behavior of the lining structure for subsea tunnels. These results are also beneficial to the optimal design of lining structures in general.  相似文献   
593.
针对目前计算机信息泄漏防护设备存在的问题,设计并实现了一种白化型信息隐藏防护设备,通过增加防护信号去白化泄漏信号,达到干扰和隐藏泄漏信息的目的.频域分析和实验测试结果表明,该设备有效隐藏了计算机的泄漏信息,并且相对于现有的泄漏信息防护设备,泄漏信息和原始信息的相关性显著下降,为计算机信息的保护提供了一种更可行的方式.  相似文献   
594.
In order to address carbon leakage and preserve the competitiveness of domestic industries, some industrialized Annex I countries have proposed to implement carbon tariffs. These tariffs would be levied on energy-intensive imports from developing non-Annex I countries that have not agreed to binding emissions reductions. This action could have detrimental welfare impacts, especially on those developing countries, and may not lead to significant reductions in leakage. A recent proposal is to use the revenues generated from carbon tariffs to finance clean development in the relevant exporting non-Annex I countries. This proposal is evaluated using an energy-economic model of the global economy. The model is supplemented by marginal abatement cost curves and bottom-up information on abatement potentials in order to represent how clean development financing affects emissions reductions. The results indicate that carbon tariffs could raise US$3.5–24.5 billion (with a central value of $9.8 billion) for clean development financing. This could reduce the emissions of non-Annex I countries by 5–15% and still leave funds available for other purposes, such as adaptation. Furthermore, recycling the revenues generated from carbon tariffs back to the exporting country itself could alleviate some of the negative welfare impacts associated with them. However, a net negative impact especially on the welfare and gross domestic product of developing countries would remain.  相似文献   
595.
《Climate Policy》2013,13(5):467-493
An oligopoly competition model is described and used to illustrate the potential effect of EU emissions trading and transport issues on the production decisions and profitability of cement producers in a typical western European country market. The role of geography is introduced from three viewpoints: the existence of regional markets, the fact that EU producers may operate multiple plants across these regions, and the possibility of production capacity constraints. A typical EU state is divided into a coastal region which is initially exposed to international competition, and an inland region which is initially protected. Assuming pure auctioning of EU Allowances and a range of CO2 prices up to €50/t, our model predicts a large increase of imports into the coastal region. Consequences for the inland producers include reduced attractiveness of the coastal market, as well as increased competition from coastal producers and from non-EU imports. The model includes a number of simplifications and therefore does not claim to offer definitive predictions, but our results do suggest that an increase in non-EU imports could feasibly offset more than 70% of the decrease in EU cement sector emissions. The likely impact on producer profits is considered for each region, and the advantages and disadvantages of potential mitigating policy measures are reviewed for either the EU Allowance allocation process or border adjustments on cement products.  相似文献   
596.
彭金灶 《探矿工程》2014,41(4):31-35,45
重点介绍了福建马坑矿区复杂地层钻探技术难点、采取的有效取心方法及护壁堵漏措施。总结了一套针对马坑矿区的钻探技术工艺,形成了具有实际参考价值的矿区施工方案,对该矿区以后的施工具有技术指导意义。  相似文献   
597.
A massive earthquake measuring 9.0 on the Richter scale that occurred on March 11, 2011, on Honshu Island, Japan, caused radioactivity leakage from the Fukushima Nuclear Power Plant, which led to the leakage of artificial nuclides (131I, 137Cs, and 134Cs) and their global transportation by atmospheric circulation. This paper re- ports a systematic comparative observation on radioactive concentrations of natural nuclides (7Be and 210Pb) and artificial nuclides (131I, 137Cs, and 134Cs) at the surface level, measured in weekly continuous aerosol sampling at Mount Guanfeng, Guiyang, China, from March 17, 2011 to April 28, 2011. During this period, the variations in the nuclide concentrations associated with their transport paths were analyzed with 315 hour back-trajectories of air mass initialized 500 m above the surface level at Guiyang. The results show that the pollutants of nuclear leakage from the Fukushima accident were transported to the Guiyang region of China via two significant pathways. In the first pathway the first wave of nuclear pollutants were transported from west to east in air masses at higher altitudes via global atmospheric circulation. The nuclear pollutants encircled the Earth almost once and after about 10 days to two weeks, between March 24 and March 31,2011, intruded Guiyang from the northwestern region of China. In the second pathway, the nuclear pollutants from the Fukushima region arrived at Guiyang between April 7 and April 14, 201 l, via air masses at lower altitudes that moved southwards because of the squeezing of the northeast Asian weather system and then by the influence, in succession, of the northeastern and southeastern air currents in the low-latitude region. The first transport pathway for atmospheric pollutants is on a global scale and based on air masses at higher altitudes, and the second transport pathway is on an eastern Asia regional scale and based on the air masses at lower altitude.  相似文献   
598.
王琴 《地下水》2014,(3):4-6
地下水人工补给技术是地下水库建设的关键技术问题之一。采用流速仪法和堰板法对台兰河现有河床渗漏能力进行实验研究,两种方法得到的结果很接近,实验研究结果表明:台兰河实验河段河床渗漏能力为0.243 m/d。此结果为台兰河地下水库人工补给方案比选提供重要依据,采用台兰河现代河床对台兰河地下水库进行人工补给是可行的。  相似文献   
599.
金军斌 《探矿工程》2017,44(4):5-9,22
顺北地区超深井二开裸眼井段长超过5000 m。针对长裸眼井段水敏和膏质泥岩缩径阻卡、二叠系火成岩漏失和垮塌、高摩阻等技术难题,开展了钻井液体系配方优化研究。通过抑制性膨胀试验、抗盐降滤失剂优选试验、复合封堵剂屏蔽封堵试验以及复合润滑剂配比和降摩阻试验,研制了强抑制高封堵低摩阻钾胺基钻井液体系。室内试验表明,二叠系火成岩在该钻井液中的滚动回收率和线性膨胀率分别达到95.09%和1.86%,钻井液能够承受5%NaCl、2?SO4和20%的钻屑污染。该钻井液体系在顺北1-2H井进行了现场试验,其长裸眼井段平均井径扩大率仅为13.55%,漏失量比顺北1-1H井降低了83.8%,复杂时间比顺北1-1H井减少了30.5 d。强抑制高封堵低摩阻钾胺基钻井液有效地解决了顺北地区长裸眼钻进技术难题,具有广阔的推广应用前景。  相似文献   
600.
堵漏试验仪是制定防漏堵漏技术方案的关键实验设备之一。针对现有堵漏试验仪普遍存在的结构复杂、试验流程繁冗、浆液用量较大、数据重现性较差等问题,设计了一种中压(试验压力为0~1 MPa)堵漏试验仪。该装置能模拟1~3 mm的条缝型漏失地层和1~4 mm的孔洞型漏失地层,封板(缝板和孔板)的实际漏失面积为0.35~2.79 cm2,孔隙率1.81%~14.24%。基于该试验装置,获取了由膨胀堵漏剂、核桃壳等组成的适于不同漏失地层的堵漏浆液配方。研究发现,堵漏浆液的封堵效果不仅取决于裂缝或孔洞的大小,也要考虑其孔隙率。该堵漏仪及堵漏浆液配方可为钻井防漏堵漏工作提供有益参考。  相似文献   
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