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61.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(5):263-270
The article contributes to the ‘new’ European regionalism by discussing the role that regional identity can play in regional development. It is based on the concept of ‘regional identity’ as the keystone of the institutionalization of the region and as consisting of two intertwined and complementary components: the regional consciousness of the inhabitants and the identity of a region. Through the heuristic study of relevant scholarly articles, the authors critically discuss six case studies from European countries dealing with the relationship between regional identity and regional development and published in the first decade of the new millennium. To date, research has examined the role of regional identity as both a successful and unsuccessful driver in regional development. From the case studies, a third possible role of regional identity is identified: regional identity as a barrier to regional development. Further, the article discusses the relationship between these three roles and attempts to identify factors causing the differentiation of the effects of regional identity in the context of regional development. 相似文献
62.
Soil‐mix technology is effective for the construction of permeable reactive barriers (PRBs) for in situ groundwater treatment. The objective of this study was to perform initial experiments for the design of soil‐mix technology PRBs according to (i) sorption isotherm, (ii) reaction kinetics and (iii) mass balance of the contaminants. The four tested reactive systems were: (i) a granular zeolite (clinoptilolite–GZ), (ii) a granular organoclay (GO), (iii) a 1:1‐mixture GZ and model sandy clayey soil and (iv) a 1:1:1‐mixture of GZ, GO and model soil. The laboratory experiments consisted of batch tests (volume 900 mL and sorbent mass 18 g) with a multimetal solution of Pb, Cu, Zn, Cd and Ni. For the adsorption experiment, the initial concentrations ranged from 0.01 to 0.5 mM (2.5 to 30 mg/L). The maximum metal retention was measured in a batch test (300 mg/L for each metal, volume 900 mL, sorbent mass 90–4.5 g). The reactive material efficiency order was found to be GZ > GZ‐soil mix > GZ‐soil‐GO mix > GO. Langmuir isotherms modelled the adsorption, even in presence of a mixed cations solution. Adsorption was energetically favourable and spontaneous in all cases. Metals were removed according to the second order reaction kinetics; GZ and the 1:1‐mix were very similar. The maximum retention capacity was 0.1–0.2 mmol/g for Pb in the presence of clinoptilolite; for Cu, Zn, Cd and Ni, it was below 0.05 mmol/g for the four reactive systems. Mixing granular zeolite, organoclay and model soil increased the chemisorption. Providing that GZ is reactive enough for the specific conditions, GZ can be mixed to obtain the required sorption. Granular clinoptilolite addition to soil is recommended for PRBs for metal contaminated groundwater. 相似文献
63.
Hydraulic performance and wave loadings of perforated/slotted coastal structures: A review 总被引:4,自引:0,他引:4
This paper reviews recent progress in the study of perforated/slotted breakwaters, with an emphasis on two main groups of such breakwaters: (1) perforated/slotted breakwaters with impermeable back walls, and (2) perforated/slotted breakwaters without a back-wall. The methods commonly used to simulate the interactions between such structures and various linear/nonlinear waves are summarized. The transmission and reflection characteristics of perforated/slotted breakwaters in these two groups are reviewed extensively. Several methods for calculating wave forces on perforated caissons are also reviewed. Some recent works published in Chinese journals, which are generally not well-known to non-Chinese researchers, are reviewed with a hope that these works can be beneficial to other researchers working in this area. 相似文献
64.
65.
The Anisian–Ladinian Latemar platform, northern Italy, presents a spectacularly exposed outcrop analogue for dolomitized carbonate reservoirs in relation to fracture-controlled igneous intrusions. Although the Latemar is one of the best studied carbonate platforms worldwide, timing and evolution of dolomitization and the link to fractures and dikes have not been explored in detail. Previous dolomite observations are based on a stratigraphically limited portion of the platform. This study extends observations to the complete exposed interval in which dolomite bodies occur, including those within the less accessible Valsorda valley.Numerous parallel mafic dikes crosscut the Latemar platform and border several of its large dolomite bodies (50 m wide, 100 m high). Within dikes and along dike-carbonate contacts, there are abundant dolomite veins that are geochemically related to surrounding dolomite bodies. Dolomitization is the result of limestone interaction with hydrothermal fluids delivered along these dikes. At dike boundaries, impermeable marble aureoles exist derived from contact metamorphism. The marble aureoles have locally shielded surrounding limestone from dolomitizing fluid. Dolomite occurs only where the ‘protective’ marble is missing or crosscut by fractures. Based on geometric relationships, we conclude that dikes and their damage zones formed the pathways for the dolomitizing fluids and functioned as boundaries for dolomite bodies.From field observations and petrography, we established a detailed paragenesis. Dolomitization started shortly after dike emplacement. There is an evolution in the Fe content of matrix dolomite and dolomite veins, from highly ferroan dolomite to non-ferroan (saddle) dolomite, alternating with episodes of silica cementation. Non-ferroan calcite precipitation followed dolomitization, possibly indicating concurrent depletion in Mg. This stage likely resulted in further limestone recrystallization rather than dolomitization. Stable and radiogenic isotopes suggest that the dolomitizing fluid comprised Carnian seawater with elevated Fe and Mg from interaction with other lithologies (possibly the nearby Predazzo intrusion). 相似文献
66.
Models of aftershock occurrence 总被引:5,自引:0,他引:5
67.
Hyperfiltration of Nacl Solutions Using a Simulated Clay/Sand Mixture at Low Compaction Pressures 总被引:1,自引:0,他引:1
It is widely recognized that clays and shales can demonstrate membrane properties. When a hydraulic head differential exists
across a membrane-functioning clay-rich barrier, some of the solute is rejected by the membrane. This process is known as
hyperfiltration. Some shallow geologic environments, including aquitards bounding shallow perched aquifers and unconfined
aquifers, some river and stream beds, and some lake bottoms contain clay–soil mixes. Many engineering structures such as landfill
liners, mixed soil augered barriers, and retention pond liners also consist of soil–clay mixes. No previous testing has been
performed to investigate the likelihood that hyperfiltration may occur in such mixed soils. Therefore, we performed five experiments
using different mixes of Na-bentonite and glass beads (100, 50, 25, 12 and 0% clay) to determine if any of these mixes exhibited
membrane properties and to investigate what effect clay content had upon the membrane properties of the soil. Each mixture
was compacted to 345 kPa and the sample mixtures were 0.58–0.97 mm thick. All the experiments used an approximately 35 ppm
Cl− solution under an average 103 kPa hydraulic head. Experimental results show that all the simulated clay–sand mixtures do
exhibit measurable membrane properties under these conditions. Values of the calculated reflection coefficient ranged from
a low of 0.03 for 12% bentonite to 0.19 for 100% bentonite. Solute rejection ranged from 5.2% for 12% clay to a high of over
30% for the 100% clay. The 100% glass bead sample exhibited no membrane properties. 相似文献
68.
69.
The reduction in sediment volume of an ebb-tide delta, as a consequence of lagoon outlet closure on a coarse clastic barrier in southeast Ireland, initiated a sequence of beachface and barrier changes downdrift. Elimination of sediment supply to the ebb-delta caused a cessation of downdrift longshore swash bar welding, and led to beach volume reductions which in turn allowed a temporal sequence of beach and nearshore morphodynamic domains to develop. These domains then controlled the sedimentation regime of the barrier adjacent to the old outlet. A temporal sequence of (a) dissipative barrier; (b) reflective barrier; and (c) inner reflective (barrier face)/outer dissipative (subtidal) wave regimes match respectively periods of (a) barrier crest build up by crestal dune development; (b) barrier crest instability (barrier width increasing, barrier height decreasing) due to rhythmic overwash; and (c) a return to barrier crest stability with limited aeolian accretion. Two barriers at different stages in this sequence are discussed. 相似文献
70.
Stephen Knight-Lenihan 《Climate Policy》2016,16(7):909-923
Applying a resilience theory framework, land transport funding in New Zealand is used to show how benefit cost analysis can reinforce a preference for maintaining existing economic and social systems when, instead, consideration of more socially disruptive options may be required. In this context, resilience is seen as the ability to maintain transport systems rather than the ability to reduce the probability of climate change. The latter role of resilience attempts to identify thresholds and regime shifts, and so critiques decision-making processes, while the former privileges social stability, thereby reducing the range of potentially useful emission mitigation options to be considered.
Policy relevance
Transitioning to a lower-carbon future requires policy formulation that challenges business-as-usual assumptions. Benefit cost analysis can be applied in ways that create barriers to such transitioning. The New Zealand case study identifies the conditions under which this can be the case. That benefit cost analysis could undermine the potential of resilience theory and application to identify low-carbon emission pathways is of concern to policy makers globally. 相似文献