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Sufficient or insufficient: Assessment of the intended nationally determined contributions (INDCs) of the world's major greenhouse gas emitters
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作者 Ge GAO Mo CHEN +4 位作者 Jiayu WANG Kexin YANG Yujiao XIAN Xunpeng SHI Ke WANG 《工程管理前沿:英文版》 2019年第1期19-37,共19页
The recent Conference of the Parties of the United Nations Framework Convention on Climate Change has resulted in the submission of the Intended Nationally Determined Contributions (INDCs) of 190 countries. This study... The recent Conference of the Parties of the United Nations Framework Convention on Climate Change has resulted in the submission of the Intended Nationally Determined Contributions (INDCs) of 190 countries. This study aims to provide an analysis of the ambitiousness and fairness of the mitigation components of the INDCs submitted by various parties. We use a unified framework to assess 23 INDCs that cover 50 countries, including European Union (EU)-28 countries as parties to the Convention, which represent 87.45% of the global greenhouse gas emissions in 2012. First, we transform initial INDC files into reported reduction targets. Second, we create four schemes and six scenarios to determine the required reduction effort, which considers each nation's reduction responsibility, capacity, and potential, thereby reflecting their historical and current development status. Finally, we combine the reported reduction target and the required reduction effort to assess INDCs. Evaluation results of the 23 emitters indicate that 2 emitters (i.e., EU and Brazil) are rated as "sufficient," 7 emitters (e.g., China, the United States, and Canada) are rated as "moderate," and 14 emitters (e.g., India, Russia, and Japan) are rated as "insufficient." Most pledges exhibit a considerable distance from representing a fair contribution. 展开更多
关键词 Intended Nationally Determined CONTRIBUTIONS MITIGATION RESPONSIBILITY capacity potential
Comprehensive analysis on China's National Climate Change Assessment Reports: Action and emphasis
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作者 Bing WANG Ge HONG +2 位作者 Chao-Qun CUI Hao YU Tad MURTY 《工程管理前沿:英文版》 2019年第1期52-61,共10页
Climate change assessment is central for lowcarbon management practice. This paper investigates China's National Climate Change Assessment Reports of 2007, 2011, and 2015. These three reports are compared with oth... Climate change assessment is central for lowcarbon management practice. This paper investigates China's National Climate Change Assessment Reports of 2007, 2011, and 2015. These three reports are compared with other climate change assessment reports by data mining. The necessity of national climate change assessment is analyzed with the requirements at home and abroad. The latest progress surrounding climate change impacts, adaptation, and mitigation is outlined with the increasing temperature rise in China and the urgency of climate change commitments. The achievements in climate change assessment indicate the increasing climate change vulnerability on sectors and regions in China and the strategies and priorities for low-carbon actions. Distinct gaps and differences are identified in the coverage of industry, regions, and vulnerability assessment between our assessments and other evaluation reports. These gaps and differences demonstrate the importance and future improvements of China's national climate change assessment in international climate governance. The outlook for China's fourth assessment report is proposed. 展开更多
关键词 climate change ASSESSMENT low-carbon management impact ADAPTATION MITIGATION
福建省地震台站防雷系统改造分析 预览
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作者 黎己余 林慧卿 俞文俊 《华北地震科学》 2019年第2期37-44,共8页
对雷电预警、电源分级防雷、信号防雷、地网建设和综合布线等多种综合防雷技术在福建省地震台站推广使用的关键点进行阐述说明,该技术在实际地震监测中取得较好的效果,可有效减轻雷击对地震观测系统仪器设备的损坏。
关键词 雷灾 地震台站 防雷技术 减轻
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Design of a tunable mass damper for mitigating vibrations in milling of cylindrical parts
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作者 Heng YUAN Min WAN Yun YANG 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第3期748-758,共11页
Milling the free-end of cylindrical parts, which are vertically fixed on the machine table,often suffers from large chatter vibrations. This kind of phenomenon is harmful to the cutting process. Therefore, it is of gr... Milling the free-end of cylindrical parts, which are vertically fixed on the machine table,often suffers from large chatter vibrations. This kind of phenomenon is harmful to the cutting process. Therefore, it is of great importance to develop means to suppress these undesirable chatters.This paper proposes a new idea for designing a tunable mass damper(TMD) to reduce vibrations in milling of cylindrical parts. Frequency response function(FRF) of the milling system is derived to comprehensively reveal the influence of both the dynamic response of the machine tools and the TMD. Critical axial depth of cut, which is usually used to characterize the process stability, is formulated by considering the FRFs of both the milling system itself and the TMD. Maximization of critical axial depth of cut is taken as objective function, while kernel dynamic parameters of TMD,which are involved in the derived expression of critical axial depth of cut, are extracted as designable variables. Optimization procedure is carried out to adjust the parameters of TMD by using sequential quadratic programming algorithm. A series of experiments with a designed passive TMD validate that the design has a good performance in reducing vibrations and improving stability of milling process. 展开更多
关键词 Chatter MILLING MITIGATION of vibrations Stability TUNABLE MASS DAMPER (TMD)
An Unmitigated Disaster: Shifting from Response and Recovery to Mitigation for an Insurable Future
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作者 Eliza de Vet Christine Eriksen +1 位作者 Kate Booth Shaun French 《国际灾害风险科学学报:英文版》 CSCD 2019年第2期179-192,共14页
Australian households are increasingly vulnerable to natural hazard-related disasters. To manage disaster risk, government commissioned inquiries have called for greater investment in mitigation. This article critical... Australian households are increasingly vulnerable to natural hazard-related disasters. To manage disaster risk, government commissioned inquiries have called for greater investment in mitigation. This article critically examines the call for a shift in funding priority towards pre-disaster mitigation measures, in the context of growing concerns around the ability of households to access and afford insurance. It examines mitigation measures in the context of three prominent Australian disasters: the Black Saturday bushfires(Victoria, 2009), the Queensland floods(2010–2011), and Cyclone Yasi(Queensland, 2011). We argue that as a mode of disaster security, mitigation operates as a complex assemblage of logics and practices of protection, preparedness, and resilience, which problematizes simplistic protection/resilience binaries. On the one hand, mitigation serves as a mode of protection, which underscores the dominant maladaptive rationality of insurance. It promises a collective solution to uninsurability that is limited by government fiscal constraints and growing employment of risk-reflective insurance pricing.On the other hand, there is evidence of an emergent rationality of household insurance as a path to resilience and preparedness—for example, in the development of insurance systems that price household retrofitting technologies and in the development of policyholder education campaigns. This resilience rationality holds the promise of securing individuals previously excluded from insurance.However, for householders lacking the necessary physical,cognitive, and financial capacities to make themselves and their properties resilient, the transition to a pre-disaster mitigation mode of security will likely do little to alleviate disadvantage and marginalization. 展开更多
关键词 Australia DISASTER MITIGATION HOUSEHOLD insurance HOUSEHOLD MARGINALIZATION HOUSEHOLD resilience Natural hazards
Research on SEE mitigation techniques using back junction and p~+ buffer layer in domestic non-DTI SiGe HBTs by TCAD
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作者 魏佳男 贺朝会 +1 位作者 李培 李永宏 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期465-471,共7页
In this paper we investigate two techniques for single event effect(SEE) mitigation by using back junction and p~+buffer layer in non-deep trench isolation(DTI) domestic silicon–germanium heterojunction bipolar trans... In this paper we investigate two techniques for single event effect(SEE) mitigation by using back junction and p~+buffer layer in non-deep trench isolation(DTI) domestic silicon–germanium heterojunction bipolar transistors(SiGe HBTs)based on technology computer aided design(TCAD) simulation. The effectiveness of the two mitigation techniques and the influence of various structure parameters are investigated. Simulation results indicate that the two techniques are more effective in reducing collector charge collection induced by heavy ions striking at positions outside the collector–substrate(C–S) junction where charge collection is dominated by diffusion. By properly adjusting the parameters, charge collection of events outside the C–S junction can be reduced by more than an order of magnitude, while charge collection of events in the device center is halved without affecting the direct current(DC) and alternating current(AC) characteristics of the SiGe HBTs. 展开更多
关键词 silicon–germanium HBT single event effect MITIGATION technique TCAD simulation
Discussion on Improving Decision-making Meteorological Service Level of County-level Meteorological Station 预览
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作者 Zhu Hexiang Wang Chufeng +1 位作者 Fu Zhaoguang Lv Xiaohua 《气象与环境研究:英文版》 CAS 2019年第2期41-43,共3页
Based on experience of meteorological service at county-level meteorological station in recent 20 years,status quo of decision-making meteorological service,main influence factors of decision-making meteorological ser... Based on experience of meteorological service at county-level meteorological station in recent 20 years,status quo of decision-making meteorological service,main influence factors of decision-making meteorological service and writing of decision-making meteorological service materials are analyzed,and measures and suggestions of improving decision-making meteorological service level are proposed. The research aims to improve public meteorological service level at grass-roots level,provide scientific decision-making basis for government departments preventing and reducing disaster,and reduce loss of life and property of the country and people caused by meteorological disasters to the maximum extent. 展开更多
关键词 METEOROLOGICAL station DECISION-MAKING SERVICE DISASTER prevention and MITIGATION SERVICE LEVEL
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Mitigation and Pragmatic Empathy 预览
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作者 LI Hai-hui 《文学与艺术研究:英文版》 2019年第2期209-220,共12页
In the pragmatics literature the relationship between mitigation and pragmatic empathy remains largely an underexplored,or even worse,a controversial issue,giving rise to the formulation of divergent views of empathy ... In the pragmatics literature the relationship between mitigation and pragmatic empathy remains largely an underexplored,or even worse,a controversial issue,giving rise to the formulation of divergent views of empathy in mitigation.While I treat empathy as a working mechanism providing a general explanation of how mitigation works,Caffi(1999;2007;2013)adopts a“paradox”view on it.The purpose of this paper is to track down the sources of divergence by comparing and contrasting our conceptualizations of mitigation.It is found that the biggest difference lies in the treatment of intersubjectivity.However,although I argue in favor of my empathic view,I see it as complementary,rather than contradictory,to Caffi’s view.The relationship between mitigation and politeness is revisited with its implications for teaching pragmatics briefly discussed. 展开更多
关键词 MITIGATION PRAGMATIC EMPATHY INTERSUBJECTIVE CONVERGENCE
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HL-2A等离子体垂直振荡缓解边缘局域模实验观测 预览
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作者 吴娜 陈少永 +5 位作者 唐昌建 宋显明 杨曾辰 余德良 许健强 HL-2A团队 《核聚变与等离子体物理》 CAS CSCD 北大核心 2019年第2期97-103,共7页
在HL-2A装置实验中,通过对水平场加入方波扰动,实现了等离子体垂直运动。当等离子体向上垂直运动时,观察到了边缘局域模(ELM)缓解现象。研究发现,等离子体向上运动过程中边缘不断形成新的闭合磁面,导致等离子体体积膨胀,进而使台基宽度... 在HL-2A装置实验中,通过对水平场加入方波扰动,实现了等离子体垂直运动。当等离子体向上垂直运动时,观察到了边缘局域模(ELM)缓解现象。研究发现,等离子体向上运动过程中边缘不断形成新的闭合磁面,导致等离子体体积膨胀,进而使台基宽度增加。此外,ELM缓解期间杂质和工作气体再循环有所增加。等离子体向上运动过程中体积膨胀、工作气体再循环及杂质增加可能是导致ELM缓解的主要物理因素。该实验可为未来聚变实验装置ELM的控制提供一些参考。 展开更多
关键词 边缘局域模 缓解 垂直振荡 HL-2A装置
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丽江玉龙雪山景区应对气候变化探索和实践 预览
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作者 邹琼 和赴宇 王珂 《环境科学导刊》 2019年第4期22-25,共4页
丽江玉龙雪山浓缩了全球中低纬度山岳冰川的精华,有丰富的现代冰川和古冰川遗迹,是世界少有的城市雪山,具有极高的科学研究和旅游观光价值。受气候变化的影响,景区面临着冰川消融加速、雪线上升、水资源短缺以及旅游吸引力下降等问题。... 丽江玉龙雪山浓缩了全球中低纬度山岳冰川的精华,有丰富的现代冰川和古冰川遗迹,是世界少有的城市雪山,具有极高的科学研究和旅游观光价值。受气候变化的影响,景区面临着冰川消融加速、雪线上升、水资源短缺以及旅游吸引力下降等问题。为应对气候变化带来的影响,景区从减缓和适应两方面实施了包括绿色交通、低碳建筑、废弃物处理、增加森林和湿地碳汇以及改善局地气候等行动和措施,为保护景区重要资源,促进地区经济和社会持续健康发展作出了的探索和实践。 展开更多
关键词 气候变化 减缓 适应 措施 玉龙雪山
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Ecological Offsetting in China’s Coastal Wetlands: Existing Challenges and Strategies for Future Improvement 预览
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作者 YU Shuling CUI Baoshan +3 位作者 XIE Chengjie MA Xu MAN Ying NING Zhonghua 《中国地理科学:英文版》 SCIE CSCD 2019年第2期202-213,共12页
Land-use changes in coastal wetlands have led to a worldwide degradation of marine coastal ecosystems and a loss of the ecological services they provide. Ecological offsetting is a popular strategy and an effective mi... Land-use changes in coastal wetlands have led to a worldwide degradation of marine coastal ecosystems and a loss of the ecological services they provide. Ecological offsetting is a popular strategy and an effective mitigation measure for ecosystems that have been degraded, damaged, or destroyed and is critical for habitats where natural recovery is hindered. However, the current understanding of the theory and practice of ecological offsetting for coastal wetlands is extremely limited in many developing countries. We conducted a review of ecological offsetting for coastal wetlands projects and studies in China in 1979–2017 to explore the application and limitations of ecological offsetting theory. It was found that China’s coastal ecological offsetting regime has recently entered a rapidly developing stage, with an increasing number of different types of offsetting projects conducted, but theoretical research lags behind practical applications. Considerable governmental, social, technological and ethical challenges remain to resolve. Coastal ecological offsetting schemes have been inconsistent in meeting conservation objectives or preventing net losses because of the challenges of ensuring they are fully consistent in practice(mainly in-kind offsets) and theory(mainly out-of-kind offsets). Ecological offsetting projects were primarily implemented by government, developers, and non-profit organizations. The available funding of coastal ecological offsetting projects is insufficient, which makes ecological offsetting a risky operation. Therefore, we propose strategies for improvement that integrate the consideration of theoretical and practical challenges in the offsetting process, while providing a scientific basis and directional guidance for the future practice of biodiversity conservation and environmental management. 展开更多
关键词 ECOLOGICAL OFFSETTING BIODIVERSITY OFFSET coastal WETLANDS no net loss MITIGATION restoration
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一种基于碳化硅IGBT的可控型直流偏磁抑制方法 预览
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作者 刘晨蕾 潘卓洪 +3 位作者 文习山 蓝磊 马静 杨娜 《电力科学与技术学报》 CAS 北大核心 2019年第1期67-73,共7页
针对高压直流输电系统大地回线运行导致的交流电网电力变压器直流偏磁问题,提出一种基于碳化硅(SiC)绝缘栅双极型晶体管与电阻串联的直流偏磁抑制方法。该方法利用碳化硅新型材料耐电压高和动作频率快的优势,通过控制半导体开关的频率... 针对高压直流输电系统大地回线运行导致的交流电网电力变压器直流偏磁问题,提出一种基于碳化硅(SiC)绝缘栅双极型晶体管与电阻串联的直流偏磁抑制方法。该方法利用碳化硅新型材料耐电压高和动作频率快的优势,通过控制半导体开关的频率以及占空比,在保证变压器有效接地的条件下将平均入地电流限制在安全阈值内;同时,利用电阻降低开关导通电流,限制中性点电压较高时的入地电流;最后,通过仿真算例校核了该方法对变压器中性点过电压的影响,仿真结果表明,该方法对直流偏磁电流具有良好抑制效果,该设备在恶劣工况下完全满足变压器中性点绝缘要求,具有较高的可行性。 展开更多
关键词 高压直流输电 直流偏磁 抑制 SIC IGBT MATLAB/SIMULINK
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论物权法定原则的缓和及其实现路径——兼谈民法典物权编立法与《民法总则》第116条的衔接 预览
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作者 王进吉 《广东外语外贸大学学报》 2019年第1期109-117,共9页
中国《物权法》第5条规定了严格的物权法定,这种封闭的物权体系导致实践中具有物权性质的权利难以得到物权法上的保护,同时也无法满足社会生活的需要,形成司法困局并阻碍了社会经济的发展,在体系上也与物权平等理念相矛盾。基于现实原... 中国《物权法》第5条规定了严格的物权法定,这种封闭的物权体系导致实践中具有物权性质的权利难以得到物权法上的保护,同时也无法满足社会生活的需要,形成司法困局并阻碍了社会经济的发展,在体系上也与物权平等理念相矛盾。基于现实原因、体系原因以及类型思维的考量,物权法定原则都有缓和的必要。《民法总则》第116条虽重申了物权法定,但未来民法典物权法编仍有规定物权法定缓和的空间。物权法定缓和的途径是扩大“法”的范围,但应只限于习惯法,而不包括行政法规、规章、地方性法规、司法解释,其方式是在物权法编基本规则中加以规定。 展开更多
关键词 物权法定 物权法定缓和 习惯法 物权法编
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Highlights of Recent Scientific Earthquake Hazard Mitigation 预览
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作者 PENG Fei 《中国地震研究:英文版》 CSCD 2019年第1期164-170,共7页
Earthquakes are a serious natural disaster faced by countries all over the world. Research on earthquake hazard mitigation are important parts of earthquake science and is a feature of China's development of earth... Earthquakes are a serious natural disaster faced by countries all over the world. Research on earthquake hazard mitigation are important parts of earthquake science and is a feature of China's development of earthquake science. In recent years, the Ministry of Science and Technology (MOST) of the People's Republic of China, the National Natural Science Foundation of China (NSFC) and the China Earthquake Administration (CEA) have attached great importance to basic research on earthquake hazard mitigation, and new opportunities and challenges have emerged. This paper collects the applications and approvals of the National Key R&D Program and the NSFC projects undertaken by the research institutes of the CEA system in recent years. The CEA system has received funding in the 13th “Five-year Plan” for “Monitoring, Early Warning and Prevention of Major Natural Disaster”. The implementation of these projects is expected to provide support for the basic science and applied research of the CEA system. In the NSFC, the number of applications from the CEA system is relatively stable, and the funding rate is slightly higher than the average for the department of earth science. Although no detailed statistical analysis has been performed, the CEA system still has room for improvement in the application of talent and major programs. I hope that the brief review of new opportunities that have arose in recent years described in this article can provide some background and new thinking for future challenges. 展开更多
关键词 EARTHQUAKE HAZARD MITIGATION Basic research Science and technology
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潜在影响防城港核电冷源系统的藻类暴发特点及其监测防控技术 预览
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作者 贺立燕 宋秀贤 +3 位作者 於凡 王凯 宋书群 俞志明 《海洋与湖沼》 CAS CSCD 北大核心 2019年第3期700-706,共7页
2014年底,在广西防城港核电厂一期工程1号机组热试期间,核电厂所在的冷源水取水海域钦州湾暴发了球形棕囊藻赤潮,赤潮严重时出现了冷却水系统堵塞现象,严重威胁到核电的安全。本次由藻类引发的威胁核电冷源安全的事件在国内尚属首例,以... 2014年底,在广西防城港核电厂一期工程1号机组热试期间,核电厂所在的冷源水取水海域钦州湾暴发了球形棕囊藻赤潮,赤潮严重时出现了冷却水系统堵塞现象,严重威胁到核电的安全。本次由藻类引发的威胁核电冷源安全的事件在国内尚属首例,以往人们更多关注核电的温排水对附近海域生物的影响,而反过来,生物对核电正常运行的潜在影响相比之下缺少研究。在此背景下,本文通过研究历史调查资料,对潜在影响防城港核电冷源系统的藻类及其暴发特点进行初步分析,以大规模暴发时易成囊、成团、成簇以堵塞核电冷源入水作为筛选标准,筛选出球形棕囊藻、束毛藻、夜光藻和浒苔几种潜在威胁种,进一步对潜在威胁种的预警监测和防控方法进行初步介绍,以达到早期预防、保障核电冷源系统安全用水的目的,并为其他核电厂提供参考。 展开更多
关键词 防城港 核电冷源 藻类 暴发 治理
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Silica-quaternary ammonium “Fixed-Quat” nanofilm coated fiberglass mesh for water disinfection and harmful algal blooms control
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作者 Daniela Diaz Jared Church +5 位作者 Mikaeel Young Keug Tae Kim Jungsu Park Yun Bin Hwang Swadeshmukul Santra Woo Hyoung Lee 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第8期213-224,共12页
Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of rec... Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of receiving surface waters. Formation of unwanted disinfection by-products(DBPs) resulting from conventional disinfection technologies reveals the need for the development of new sustainable alternatives. Quaternary Ammonium Compounds(QACs) are cationic surfactants widely known for their effective biocidal properties at the ppm level. In this study, a novel silica-based antimicrobial nanofilm was developed using a composite of silica-modified QAC(Fixed-Quat) and applied to a fiberglass mesh as an active surface via sol–gel technique. The synthesized Fixed-Quat nanocoating was found to be effective against E. coli with an inactivation rate of 1.3 × 10^-3 log reduction/cm min. The Fixed-Quat coated fiberglass mesh also demonstrated successful control of Microcystis aeruginosa with more than 99% inactivation after 10 hr of exposure.The developed antimicrobial mesh was also evaluated with wild-type microalgal species collected in a water body experiencing HABs, obtaining a 97% removal efficiency. Overall,the silica-functionalized Fixed-Quat nanocoating showed promising antimicrobial properties for water disinfection and HABs control, while decreasing concerns related to DBPs formation and the possible release of toxic nanomaterials into the environment. 展开更多
关键词 FIBERGLASS mesh HAB mitigation NANOCOATING Quaternary ammonium compounds(QACs) Silica-functionalization Water DISINFECTION
Challenges to increasing the soil carbon pool of agro-ecosystems in China 预览
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作者 LIN Er-da GUO Li-ping JU Hui 《农业科学学报:英文版》 SCIE CAS CSCD 2018年第4期723-725,共3页
Climate change will place agro-ecological systems and food security at serious risk. At the 21st Conference of the Parties(COP21) in Paris in December of 2015, parties to the United Nations Framework Convention on C... Climate change will place agro-ecological systems and food security at serious risk. At the 21st Conference of the Parties(COP21) in Paris in December of 2015, parties to the United Nations Framework Convention on Climate Change (UNFCCC)reached a historic agreement (Paris Agreement) to combat climate change and to accelerate and intensify the actions andinvestments needed for a sustainable low carbon future. An initiative named the "4%o initiative: Soils for food security andclimate" was proposed by the French Minister of Agriculture, and this initiative was launched officially at the COP21 andadopted by many global organizations. The aim of this initiative was to increase carbon sequestration in soil to mitigatefossil fuel combustion emissions of greenhouse gasses. The present study found that China has high CO2 emissions buta low soil carbon pool, and indicates that 4%o increments of the soil carbon pool will not be sufficient to offset national CO2emissions. The current soil carbon sequestration rate would also not reach the mean level requested by the initiative.Therefore, China faces big challenges to achieve this initiative. An integrated use of straw technology may be used morewidely to improve Carbon sequestration, and other opportunities include improved fertilizer use efficiency and greenhousegas mitigation through the waste management project under construction in China. This paper suggests that China mayput forward the biomass treatment centered high yield and fertilizer-carbon sequestration project to enhance resilience ofagro-ecosystems to climate change. 展开更多
关键词 soil organic carbon SEQUESTRATION climate change GREENHOUSE gas MITIGATION agriculture RESILIENCE
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Ships Bottom Cavities as Shock Absorbers in Waves 预览
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作者 Eduard Amromin 《船舶与海洋工程学报:英文版》 CSCD 2018年第2期173-177,共5页
Bottom ventilated cavitation is the successfully proven ship drag reduction technology,but the impact of sea waves on ships with bottom cavities is the substantial concern for a broad technology implementation.The inf... Bottom ventilated cavitation is the successfully proven ship drag reduction technology,but the impact of sea waves on ships with bottom cavities is the substantial concern for a broad technology implementation.The influence of waves on vertical force experienced by such ships is analyzed in this paper using a perturbation technique.The unperturbed cavity shape at given Froude number and cavity length was found from a nonlinear steady ideal fluid problem.The ship response to an impact of a wave of the given length and amplitude is considered as the one-frequency perturbation.This perturbation was found by combined consideration of compressible flow in the cavity and incompressible flow in the surrounding water.Computational examples relate to an earlier tested model with the bottom cavity restricted by skegs.The vertical forces on the model with bottom cavities and in cavitation-free conditions were compared in head and following seas.It was found that within the major part of the consider range of wavelengths the cavity acts as a shock absorber significantly reducing the vertical force pulsation and ship acceleration in waves. 展开更多
关键词 Ship BOTTOM CAVITATION Wavy SEAS MITIGATION of force PULSATION Vertical acceleration
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完善中国气候变化适应性立法的思考 预览
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作者 曹明德 《中州学刊》 CSSCI 北大核心 2018年第8期53-57,共5页
中国正在起草应对气候变化法,在气候变化立法中如何处理减缓与适应之间的关系是一个重要命题。从中国作为发展中国家的国情和气候变化脆弱性来看,确立适应气候变化在立法中的重要地位十分必要。同时,中国应当在气候变化立法中确立适应... 中国正在起草应对气候变化法,在气候变化立法中如何处理减缓与适应之间的关系是一个重要命题。从中国作为发展中国家的国情和气候变化脆弱性来看,确立适应气候变化在立法中的重要地位十分必要。同时,中国应当在气候变化立法中确立适应气候变化的指导思想、立法宗旨和目标,确定适应气候变化立法的基本原则、法律规制的重点领域,以及适应气候变化的关键制度等内容,从而进一步增强中国应对气候变化的能力。 展开更多
关键词 气候变化 适应 减缓 气候变化保险 气候变化基金
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解淀粉芽孢杆菌HM618对镉胁迫下小麦幼苗生长的影响 预览
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作者 庞亚琴 任彩婷 徐秋曼 《天津师范大学学报:自然科学版》 CAS 北大核心 2018年第4期55-59,共5页
为了探究根际促生菌解淀粉芽孢杆菌HM618对重金属镉胁迫下小麦幼苗生长的影响,采用不同体积的解淀粉芽孢杆菌HM618发酵液处理不同程度镉胁迫下的小麦幼苗,测定根长、株高、叶绿素、可溶性蛋白、可溶性糖、脯氨酸和丙二醛含量等生长和生... 为了探究根际促生菌解淀粉芽孢杆菌HM618对重金属镉胁迫下小麦幼苗生长的影响,采用不同体积的解淀粉芽孢杆菌HM618发酵液处理不同程度镉胁迫下的小麦幼苗,测定根长、株高、叶绿素、可溶性蛋白、可溶性糖、脯氨酸和丙二醛含量等生长和生理指标.结果表明:不同施加量的解淀粉芽孢杆菌HM618发酵液对小麦幼苗均有一定的促生作用,尤其是对根部的促生作用显著.镉胁迫会导致小麦幼苗的叶绿素和可溶性蛋白含量下降,可溶性糖、脯氨酸和丙二醛含量增加,在解淀粉芽孢杆菌的作用下,小麦幼苗的叶绿素和可溶性蛋白含量均显著增加,而可溶性糖、脯氨酸和丙二醛的含量均减少.总的来看,解淀粉芽孢杆菌HM618对小麦幼苗遭受的镉胁迫具有缓解作用,且发酵液的使用量越大,缓解效果越显著;小麦幼苗遭受的镉胁迫程度越严重,解淀粉芽孢杆菌的缓解效应越显著. 展开更多
关键词 解淀粉芽孢杆菌 镉胁迫 小麦幼苗 生理活性 缓解
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