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11.
In recent years, bio-energy with carbon capture and storage (BECCS) has been awarded a key role in climate mitigation scenarios explored by integrated assessment models and referenced in reports by the Intergovernmental Panel on Climate Change. Because a majority of scenarios limiting global warming to 2 °C or 1,5 °C include vast deployment of BECCS, a critical discussion has emerged among experts about the moral implications of thus introducing an unproven technology into the policy realm.In this paper, we analyse this discussion as it has played out between 2013 and 2019, with a focus on how expert narratives are constructed in the mass media about the possibilities for decarbonisation within the current political-economic order. We find there are almost no narratives that support massive deployment of BECCS, and that all narratives presuppose limits to decarbonisation imposed by the current political-economic system. The perception of such limits lead some to argue, through deterministic and apolitical narratives, for the necessity of negative emissions technologies, while others argue instead that “degrowth” is the only solution. Thus, there is a distinct lack of positive narratives about how capitalism can bring about decarbonisation.  相似文献   
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全球化进程下,跨国移民成为不同地域间文化交流、冲突和再协商的主要载体,其在地饮食适应问题尤为凸显。本文回顾了国内外跨国移民饮食适应的研究,发现由营养学等范式主导的早期研究偏重对饮食适应水平的直接观测,较少探究饮食适应的身体属性、地方关系以及文化意涵。文化地理学视角下的跨国移民饮食适应的相关研究进展主要包括以下三个方面:身体尺度下的动态饮食适应过程、地方尺度下跨国饮食景观的生产与重构,以及身体与地方交互尺度下饮食适应与身份认同的复杂关系。本文最后针对当前研究的主要不足提出未来跨国移民饮食适应研究的可能议题。  相似文献   
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移动性是21世纪人文地理的研究热点和重要议题,它体现了空间科学的社会学转向,属于人文地理学的核心概念和中心命题,其中心性突出体现在它与其他传统和新兴的人文地理分支学科的交叉。本文以表格为工具梳理了地理移动性的研究理路,发现移动地理与其他人文地理分支学科共同聚焦的核心是:时间地理、旅游地理、行为地理的“时空行为”问题,政治地理、社会地理的“权力”“平等”“权利”问题,身体地理的“具身实践”“感官体验”问题,情感地理的“地方依恋”“身份认同”问题,想象地理的“地方感”问题,道德地理的“空间道德感”问题。本文识别这些关键问题为移动地理的“核心要素”,搭建移动地理的框架和体系,指出探查这些要素之间相互作用机制和不同时空移动类型的转化机理是未来移动性的研究方向。根据移动的空间尺度和时间强度,构建了包括日常移动、旅游和旅行移动到永久性移动在内的地理学移动性连续轴类型,并探索了移动地理研究的方法论体系。  相似文献   
15.
聚醋酸乙烯酯(PVAc)乳液是常见的彩绘类文物保护材料。采用激光粒度仪、热重/差热分析、红外光谱、X-射线衍射、扫描电镜、透射电镜等表征了PVAc乳液的粒径以及胶膜的热稳定性、结构和形貌;采用粘度计、表面张力仪、pH计、电导率仪等研究了乳液浓度与其粘度、表面张力、pH、电导率的关系;通过冻融、室温-高温放置、离心分离研究了乳液的稳定性;同时用PVAc乳液对模拟起甲和酥碱的壁画进行了修复。结果表明,PVAc乳液粒径呈双峰分布,小粒子的平均粒径为380 nm,大粒子的平均粒径为5.85μm;乳液胶膜为非结晶物质,胶膜热重的最终质量残留为1.54%,335℃出现放热峰。PVAc乳液的电导率随浓度的增大而增大,pH随浓度的增大而下降;相同温度下表面张力随浓度的增大而基本呈现低浓度下降,高浓度上升的趋势。相同浓度下,表面张力随温度升高而无显著变化,表明PVAc乳液的表面张力受温度变化影响不大。相同温度下,乳液粘度随浓度的增大而增大;相同浓度下,乳液的粘度随温度的升高而降低。冻融、离心分离和不同温度下静置发现,该乳液出现分层。用该乳液对模拟起甲和酥碱壁画修复后,再分别老化20个循环和12个循环,发现颜料层再次空鼓、起甲。综合分析,说明实验中所使用的该种PVAc稳定性和抗老化能力较弱,在修复彩绘类文物中应慎重选择PVAc的种类,综合考虑PVAc的使用浓度、环境因素对其性能的影响,以达到最佳使用效果。  相似文献   
16.
慈利白公城遗址历史悠久,具有重要的考古价值。该遗址出土了大量木质井壁及少量其他木质文物,为了解这些木材的特点,以及为木材保护提供相关的参考,通过徒手切片,并利用光学显微镜对该遗址出土的10件木质样品进行鉴定。结果表明其中1件为无患子(Sapindus. mukorossi Gaertn.),1件为冷杉(Abies fabri(Mast.)Craib),2件为湖南杨桐(Adinandra. acutifolia Hand.-Mazz.),2件为香椿(Toona sinensis A. Juss.),4件为润楠(Machilus pingii Cheng ex Yang)。通过实验结果,初步推测井壁的制作在当时是比较重要的工作,此时已经在选择性地使用木质井壁原料。从树种适宜生长的环境上看,同时期该遗址附近可能是以阔叶材为主的针阔叶混交林,气候温暖湿润。  相似文献   
17.
We analyze the general equilibrium effects of an asymmetric decrease in transport costs, combining a large-scale spatial dynamic general equilibrium model for 267 European NUTS-2 regions with a detailed transport model at the level of individual road segments. As a case study, we consider the impact of the road infrastructure investments in Central and Eastern Europe of the European Cohesion Policy. Our analysis suggests that the decrease in transportation costs benefits the targeted regions via substantial increases in gross domestic product (GDP) and welfare compared to the baseline, and a small increase in population. The geographic information embedded in the transport model leads to relatively large predicted benefits in peripheral countries such as Greece and Finland, which hardly receive funds, but whose trade links cross Central and Eastern Europe, generating profit from the investments there. The richer, Western European nontargeted regions also enjoy a higher GDP after the investment in the East, but these effects are smaller. Thus, the policy reduces interregional disparities. There are rippled patterns in the predicted policy spillovers. In nontargeted countries, regions trading more intensely with regions where the investment is taking place on average benefit more compared to other regions within the same country, but also compared to neighboring regions across an international border. We uncover that regions importing goods from Central and Eastern Europe enjoy the largest spillovers. These regions become more competitive and expand exports, to the detriment of other regions in the same country.  相似文献   
18.
In this paper, we develop a three-region economic geography model with workers of heterogeneous skills and mobility rates to consider how first-nature, regional differences impact both inter- and intraregional inequality. In our model, the skill premium within a region summarizes both the degree of intraregional inequality between mobile, skilled workers and immobile, unskilled workers and the interregional inequality through differences in the welfare of unskilled workers across regions. Regions with the highest skill premium have the greatest degree of intraregional inequality and provide the lowest level of welfare to unskilled workers, relative to other regions. We find that the skill premium will be higher in regions with a greater supply of unskilled labor, lower supply of housing, or are more remote. An increase in a region's housing supply or centrality will lower intraregional inequality and raise the welfare of the local, unskilled workforce. However, the magnitude of these changes are declining in the initial number of skilled workers in the region. The model is extended to consider imperfectly elastic housing supply. The larger the price elasticity of housing, the larger the range of values, such that more populated regions will host a disproportionate share of skilled workers, have lower levels of intraregional inequality, and provide higher levels of welfare for unskilled workers.  相似文献   
19.
Madeline Bass 《对极》2023,55(1):49-69
In September 2020, Oromo women marched through the streets of Berlin, Germany, demanding recognition for their struggle. This protest march, called a Hiriira in the Oromo language, offers a case study into the entanglements between settler colonial Ethiopia, Germany’s post-empire, and the forces of oppression which link them. This paper uses the spatiotemporal reckonings generated from the Hiriira perspective to understand violence and elucidate the practices of resistance that have emerged despite it. These contrasting ways of viewing space and time are expressed through the tension between imperial spatialising, a way of knowing the world that is imperial and oppressive in nature, and geography guraacha, a Black and Blackened way of knowing space with a particularly Oromo perspective. The result is a type of mapping, tracing the Hiriira route across Berlin while describing the histories that shadow these streets, and the pathways towards liberation that Oromo women are organising.  相似文献   
20.
Julia Sizek 《对极》2023,55(6):1898-1918
A proposed project will take water from an aquifer in the California desert to the coast. Lacking final approvals more than 30 years after it started, the project remains a plan despite sizeable opposition. What is its secret? In this paper, I examine the imaginaries of the underground aquifer underneath the lands of Cadiz Inc, the project proponent. While local theories insist the company is at the centre of a Chinatown conspiracy, I argue that the company stays alive through regulatory alchemy, a term that reveals the magic at the heart of scientific and regulatory approval processes. I examine narratives of the aquifer in environmental compliance and financial reporting in order to reveal how regulatory processes become the conditions of profit-making, building on debates in critical legal geography and political ecology.  相似文献   
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