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31.
This paper seeks to make a contribution to on-going debates about how to conceptualise the spatial processes of renewable energy transition. It makes a case for understanding renewable energy transitions as simultaneously spatial and political processes, constitutive of new territories and configuring development pathways. Drawing on a case study of South Africa's Renewable Energy Independent Power Procurement Programme (REI4P), the paper explores the ways in which energy transitions are intrinsically bound up with both the materiality and the historical and contemporary politics of land. It then examines the relationship between energy transitions and territory to conceptualise the ways in which transitions take on an experimental shape in the form of 'zones'. The paper argues that these zones are new territories deploying forms of spatial and political-administrative exceptionality, which allow political and economic actors to exercise authority and commercial power. Two types of zone emerging from South Africa's energy transition exemplify these processes: legally-defined zones for the development of solar and wind energy and zones of socioeconomic development required by REI4P. The paper explores the spatial and political consequences of these strategies and suggests that these may not necessarily translate into conflict and confrontation, but instead produce uneasy co-existences of different political, social and spatial projects and interests, with potential to create new polities.  相似文献   
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33.
Human-induced global threats are compelling many anthropologists to rethink roles, methods, and paradigms and engage in public debate and action on energy policies, extraction processes, commodity chains, and consumption. Laura Nader's Energy Reader embodies her decades-long engagement as a catalyst for public debate on U.S. energy issues. Tanja Winther's Impact of Electricity exemplifies ethnography informing development practice. Strauss and colleagues’ Cultures of Energy reflects diverse approaches seeking to build cultural understandings to inform energy choices. There remains a need for collaboration with anthropologists embedded in energy-related agencies—positioned where they can leverage anthropological knowledge to push policy envelopes.  相似文献   
34.
To investigate the kinetics of interfacial energy‐driven fluid infiltration, experiments were carried out in a quartzite–water system at 621–925°C and 0.8 GPa. Infiltration couples were made by juxtaposing presynthesized dry quartzite cylinders and fluid reservoirs. The infiltration process was confirmed by the presence of pores at the quartzite grain edges. As predicted from theoretical considerations and previous experiments, wetting fluids such as pure water and NaCl aqueous solution infiltrated into quartzite, whereas nonwetting CO2‐rich fluids did not. Newly precipitated quartz layers at the surfaces of the infiltrated sample proved that infiltration took place by a dissolution–precipitation mechanism. The enhancement of grain growth by fluid infiltration was observed over the entire range of experimental temperatures. The fluid fraction, gauged by the porosity of the run products, increases at the infiltration front and then decreases towards the fluid reservoir to form a high‐porosity zone with a maximum porosity of 2.3–2.9%. As infiltration proceeds, the high‐porosity zone advances like a travelling wave. This porosity wave is probably caused by a grain curvature gradient resulting from preferential grain growth in the infiltrated part of the quartzite, perhaps combined with other factors. The infiltration kinetics were modelled with a steady‐state diffusion model over the high‐porosity zone. The solubility difference between dissolving and precipitating grains was deduced to be 2 × 10?2?3 × 10?1 wt %. The experimentally obtained infiltration rate of aqueous fluid in the steady‐state diffusion regime (2 ± 0.5 × 10?8 m sec?1 at 823°C) is much faster than the estimated metamorphic fluid flux rates, so that interfacial energy‐driven fluid redistribution in quartz‐rich layers could significantly contribute to the fluid flux in high‐grade metamorphism, at least over a short distance. Cathodoluminescence observations of the run products revealed that the grain growth of quartzite in the presence of fluid proceeds extensively, which would promote the chemical equilibration between fluid and rock more effectively than would volume diffusion in quartz crystals.  相似文献   
35.
This article presents an experimental investigation of the seismic performance of gravity load-designed RC infilled frames and confined bearing walls of limestone masonry backed with plain concrete. Five infilled frames and two bearing walls were constructed at one-third scale and tested using reversed cyclic lateral loading and constant axial loads. Effects of openings, axial loading, and infill interface conditions were examined using quasi-static experimentation. The two structural systems exhibited similar lateral resistance and energy dissipation capacities with higher global displacement ductility for the infilled frames. Hysteretic behavior of the infilled frame models exhibited pinching of the hysteretic loops accompanied by extensive degradation of stiffness whereas loops of the bearing walls were free of pinching. Test results confirmed the beneficial effect of axial loading on lateral resistance, energy dissipation, and ductility of the bearing walls. Higher axial loading resulted in a substantial decrease in ductility with no significant effect on lateral resistance of the infilled frames. Openings within the infill panel reduced significantly the lateral resistance of infilled frames. Using dowels at the infill panel interfaces with the base block and bounding columns enhanced the maximum load-carrying capacity of infilled frames without impairing their ductility.  相似文献   
36.
Thermohaline convection of subsurface fluids strongly influences heat and mass fluxes within the Earth's crust. The most effective hydrothermal systems develop in the vicinity of magmatic activity and can be important for geothermal energy production and ore formation. As most parts of these systems are inaccessible to direct observations, numerical simulations are necessary to understand and characterize fluid flow. Here, we present a new numerical scheme for thermohaline convection based on the control volume finite element method (CVFEM), allowing for unstructured meshes, the representation of sharp thermal and solute fronts in advection‐dominated systems and phase separation of variably miscible, compressible fluids. The model is an implementation of the Complex Systems Modelling Platform CSMP++ and includes an accurate thermodynamic representation of strongly nonlinear fluid properties of salt water for magmatic‐hydrothermal conditions (up to 1000°C, 500 MPa and 100 wt% NaCl). The method ensures that all fluid properties are taken as calculated on the respective node using a fully upstream‐weighted approach, which greatly increases the stability of the numerical scheme. We compare results from our model with two well‐established codes, HYDROTHERM and TOUGH2, by conducting benchmarks of different complexity and find good to excellent agreement in the temporal and spatial evolution of the hydrothermal systems. In a simulation with high‐temperature, high‐salinity conditions currently outside of the range of both HYDROTHERM and TOUGH2, we show the significance of the formation of a solid halite phase, which introduces heterogeneity. Results suggest that salt added by magmatic degassing is not easily vented or accommodated within the crust and can result in dynamic, complex hydrologies.  相似文献   
37.
Abstract

In France, the public acceptability of marine renewable energies and their impacts on ecosystem services (ES) involves questions about compensation for stakeholders, who may perceive some of their activities and interests to be modified. This paper seeks to understand how impacts on ES are perceived by institutional stakeholders and what is expected in terms of compensation. It also seeks to identify the communities of practice affected. We focus our study on the planned offshore wind farm in the bay of Saint-Brieuc. Our results show that institutional discourse is heterogeneous, depending on sensitivities, interests, and who or what the stakeholders surveyed represent or defend. Stakeholders' discourse can be interpreted on various gradients of perception. Six distinct communities of practice have been identified, based on the impacts perceived by institutional stakeholders. Lastly, we show that the community of practice seems to be a proper level at which to study perceptions and assess the no-net-loss goal.  相似文献   
38.
Thermal springs are commonly thought to be an indicator of geothermal resource potential. However, there have been few analyses of the relationship between thermal springs and the underlying thermal regime. An examination of temperature and discharge rates for a large database of thermal springs in North America demonstrates that there is not a simple relationship between these measurements made at the surface and subsurface heat flow. Hydrogeological factors appear to exert strong controls on the temperature and discharge at these springs and should be carefully considered in geothermal resource assessments.  相似文献   
39.
The conservation of historic stone buildings and sculptures is recently receiving growing attention and becoming a focus of research because of rapid changes in weather conditions (pollution, acid rain, etc.). Presently, techniques for stone conservation primarily involve the use of organic coating treatments, but their side effects have been recognized. In contrast, some traditional materials used in historic stone buildings function well for thousands of years. In this paper, we report our research on the reasons why traditional protective materials can provide an unexpected long-term protection. First, calcium carbonate was prepared according to a formula for making Chinese traditional consolidating materials, and its structure and morphology were examined by different instruments. Second, the reinforcing effectiveness of the prepared CaCO3 powders was tested and analyzed by investigating its surface characteristics. The experimental results reveal that a biocontrolled process occurs, in which an organic template can induce the precipitation of a mineral structure, which in turn results in a great improvement in the conservation of the historic stone buildings protected by these traditional protective materials. This provides a contribution toward the development of new researches on biocontrolled processes and on some protective materials with excellent performance through biocontrolled synthesis.  相似文献   
40.
宋志宏  杜继明  王珍珍 《神州》2011,(3X):167-169
随着社会进入信息化及电子智能化时代,电子技术发展越来越迅速,应用越来越广泛,对人类生活的影响也更加深远。节能减排、保护环境,是全世界、全人类共同关心的问题,也是我国社会经济发展的重要问题。  相似文献   
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