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911.
The global rise in atmospheric greenhouse gas concentrations calls for practicable solutions to capture CO2. In this study, a mineral carbonation process was applied in which CO2 reacts with alkaline lignite ash and forms stable carbonate solids. In comparison to previous studies, the assays were conducted at low temperatures and pressures and under semi-dry reaction conditions in an 8 L laboratory mixing device. In order to find optimum process conditions the pCO2 (10-20%), stirring rate (500-3000 rpm) and the liquid to solid ratio (L/S = 0.03-0.36 L kg−1) were varied. In all experiments a considerable CO2 uptake from the gas phase was observed. Concurrently the solid phase contents of Ca and Mg (hydr)oxides decreased and CaCO3 and MgCO3 fractions increased throughout the experiments, showing that CO2 was stabilized as a solid carbonate. The carbonation reaction depends on three factors: Dissolution of CO2 in the liquid phase, mobilization of Ca and Mg from the mineral surface and precipitation of the carbonate solids. Those limitations were found to depend strongly on the variation of the process parameters. Optimum reaction conditions could be found for L/S ratios between 0.12 and 0.18, medium stirring velocities and pCO2 between 10% and 20%.Maximum CO2 uptake by the solid phase was 4.8 mmol g−1 after 120 min, corresponding to a carbonation efficiency for the alkaline material of 53% of the theoretical CO2 binding capacity. In comparison to previous studies both CO2 uptake and carbonation efficiencies were in a similar range, but the reaction times in the semi-dry process were considerably shorter. The proposed method additionally allows for a more simple carbonation setup due to low T and P, and produces an easier to handle product with low water content. 相似文献
912.
Disconnected policies and actors and the missing role of spatial planning throughout the risk management cycle 总被引:2,自引:2,他引:0
Kalliopi Sapountzaki Sylvia Wanczura Gabriella Casertano Stefan Greiving Gavriil Xanthopoulos Floriana F. Ferrara 《Natural Hazards》2011,59(3):1445-1474
The present work addresses the problem of lack of coordination between policies and actors with joint competence for risk
management, i.e., civil protection, spatial planning, and sectoral planning (e.g., forest policy in the case of forest fire
risk). Spatial planning in particular is assigned a minor or no role at all though it might perfectly operate as the coordinating
policy platform; the reason is that spatially relevant analysis and policy guidance is an omnipresent component of the risk
management cycle. However, disconnected risk relevant policies turning a blind eye to spatial planning might cause several
adverse repercussions: Breaks in the response-preparedness-prevention-remediation chain (which should function as a continuum),
minimal attention to prevention, risk expansion and growth instead of mitigation, lack of synergies between involved actors
as well as duplicated or even diverging measures and funding. The authors bear witness to the above suggestions by examining
three cases of European (regional and local) risk management systems faced with failures when confronting natural hazards
(floods and forest fires). These three systems are embedded in different types of political-administrative structures, namely
those of the city of Dortmund (Germany) facing floods, Eastern Attica region (Greece), and Lazio Region (Italy) facing forest
fires. 相似文献
913.
Senecio Schefer Vladica Cvetković Bernhard Fügenschuh Alexandre Kounov Maria Ovtcharova Urs Schaltegger Stefan M. Schmid 《International Journal of Earth Sciences》2011,100(5):1181-1206
Two age groups were determined for the Cenozoic granitoids in the Dinarides of southern Serbia by high-precision single grain
U–Pb dating of thermally annealed and chemically abraded zircons: (1) Oligocene ages (Kopaonik, Drenje, Željin) ranging from
31.7 to 30.6 Ma (2) Miocene ages (Golija and Polumir) at 20.58–20.17 and 18.06–17.74 Ma, respectively. Apatite fission-track
central ages, modelling combined with zircon central ages and additionally, local structural observations constrain the subsequent
exhumation history of the magmatic rocks. They indicate rapid cooling from above 300°C to ca. 80°C between 16 and 10 Ma for
both age groups, induced by extensional exhumation of the plutons located in the footwall of core complexes. Hence, Miocene
magmatism and core-complex formation not only affected the Pannonian basin but also a part of the mountainous areas of the
internal Dinarides. Based on an extensive set of existing age data combined with our own analyses, we propose a geodynamical
model for the Balkan Peninsula: The Late Eocene to Oligocene magmatism, which affects the Adria-derived lower plate units
of the internal Dinarides, was caused by delamination of the Adriatic mantle from the overlying crust, associated with post-collisional
convergence that propagated outward into the external Dinarides. Miocene magmatism, on the other hand, is associated with
core-complex formation along the southern margin of the Pannonian basin, probably associated with the W-directed subduction
of the European lithosphere beneath the Carpathians and interfering with ongoing Dinaridic–Hellenic back-arc extension. 相似文献
914.
Ingemar Bergelin Karsten Obst Ulf Söderlund Kent Larsson Leif Johansson 《International Journal of Earth Sciences》2011,100(4):787-804
More than 100 volcanic necks composed of basanites and melanephelinites occur in Scania, southern Sweden, at the junction
of two major tectonic lineaments, the Phanerozoic Sorgenfrei-Tornquist Zone (STZ) and the Proterozoic Protogine Zone. New
40Ar/39Ar isotope analyses of whole rock fragments of nine selected basalt necks suggest that the Mesozoic alkaline volcanism in
the Scanian province commenced earlier than previously reported and comprised three separate volcanic episodes that span a
total period of ca. 80 Myr: a first Jurassic (191–178 Ma), a second at the Jurassic/Cretaceous boundary (ca. 145 Ma), and
a final middle Cretaceous episode (ca. 110 Ma). The new results allow for precise time correlations between eruption events
in the Scanian and those in the North Sea volcanic provinces. The older, early Jurassic event in Scania is largely synchronous
with that in the Egersund Basin and the Forties field whereas the event at ca. 145 Ma is correlated with activity in the Central
Graben. These volcanic episodes also correlate in age with Kimmerian tectonic activity. Volcanic activity in the middle Cretaceous
period has also been dated in the triple junction in the North Sea and offshore in the Netherland Sector. The correlation
of basalt volcanism in Scania with the Egersund nephelinites strongly suggest that volcanism was triggered by repeated tectonic
activity along the STZ. Geochemical data of alkaline mafic rocks in the Scanian and the North Sea volcanic provinces imply
that different provinces have largely unique geochemical signatures in favour of a heterogeneous mantle in the North Sea volcanic
region. However, basalts of different generations in one and the same province cannot be readily separated on the basis of
geochemistry, suggesting that the same lithospheric mantle was the source of repeated volcanism over time in each province.
The data suggest a low degree of melting of a volatile-bearing mantle lherzolite enriched in incompatible elements with the
exception of the Forties basalts in the rift centre, produced by larger degree of melting and evolved by fractional crystallization. 相似文献
915.
Nicholas Deichmann John Clinton Stephan Husen Benjamin Edwards Florian Haslinger Donat Fäh Domenico Giardini Philipp Kästli Urs Kradolfer Stefan Wiemer 《Swiss Journal of Geoscience》2011,104(3):537-547
This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during
2010. During this period, 407 earthquakes and 85 quarry blasts were detected and located in the region under consideration.
With a total of only 19 events with ML ≥ 2.5, the seismic activity in the year 2010 was below the average over the previous 35 years. The two most noteworthy earthquakes
were the ML 3.4 Barrhorn event near Sankt Niklaus (VS) and the ML 3.0 event of Feldkirch, both of which produced shaking of intensity IV. 相似文献
916.
Maria Falaleeva Cathal O'Mahony Stefan Gray Margaret Desmond Jeremy Gault Valerie Cummins 《Marine Policy》2011
Coastal environments are susceptible to a range of impacts arising from medium and long-term climate change. However, as Ireland's population and industrial centres are concentrated in coastal locations, Ireland's coastal communities will be particularly vulnerable to the impacts of climate change. Therefore, making the best use of existing knowledge to inform the establishment of governance structures capable of facilitating the measures and actions which may soon be required is a national imperative. Coastal communities worldwide have turned to integrated coastal zone management (ICZM) as a process to deliver sustainable development. This paper explores how experience gained from ICZM implementation can be harnessed to inform the development and implementation of climate adaptation policies, with a particular focus on the coastal zone. Using the principles and conceptual basis of Earth System Governance – an emerging approach to analyse complexity of governance under global environmental change – the paper maps the architecture of ICZM and climate governance in Ireland. The research identifies the main barriers to, and opportunities for, integrated application of the two policy domains. Barriers include the fragmentation of governance structures and responsibilities of key stakeholders, a lack of coordinated support for ICZM implementation at the national level, and a relatively weak awareness of the specifics of adaptation at the local level. Opportunities include the availability of expertise gathered from phases of ICZM implementation in Ireland, which encompasses mechanisms for science-policy integration, and invaluable experience of stakeholder participation and interaction. Current political and scientific support at national and EU levels give an additional impetus to climate research and actions which may bring additional opportunities and resources to coastal governance in Ireland. 相似文献
917.
The location, shape and stacking pattern of deep‐marine clastic sediments on drifting stage passive continental margins are strongly influenced by the slope and basin floor topography. The tectonic control on sediment routes and dispersal patterns, however, is less understood on rift margins, particularly the impact of subaqueous transfer zones or relay ramps. In this study, an area of the Palaeocene marine syn‐rift succession in the Vøring Basin is mapped in detail to unravel the relationship between fault geometries and sedimentary infill patterns. Using root‐mean‐square (RMS) amplitudes and deposit thicknesses interpreted from seismic data, sedimentary elements in the Fenris Graben and the Gjallar Ridge are related to the fault patterns and the overall basin geometry. Older deposits are found to be aligned parallel to the basin axis, with the greatest sediment thicknesses on the hanging walls and adjacent to rotated faults. The main sediment supply is interpreted to be sourced from the Vøring Marginal High and Greenland, presumably containing a significant proportion of coarser grained material and comprising numerous local depocentres. With continued rifting and decreased fault activity, finer grained deposition draped the previous basin infill and smoothed the basin floor topography. Deposits close to the foot of relay ramps along the Gjallar Ridge, however, suggest that the high may have acted as a local sediment source leading to local depocentres. Transfer zones played a significant role in sediment transport during the early rifting phase, and were able to maintain some influence into the late rifting and early drifting stage. Identification of early‐ and late‐stage transfer zones may therefore help in locating coarser grained depocentres and potential hydrocarbon reservoirs. 相似文献
918.
Zieger Stefan Greenslade Diana J. M. Aijaz Saima Kepert Jeffrey D. Burton Andrew 《Ocean Dynamics》2021,71(5):559-588
Ocean Dynamics - This paper describes a series of hindcast simulations of 17 tropical cyclones over the northwest shelf region of Australia. Tropical cyclone track and vortex details were obtained... 相似文献
919.
E. Vigren J. Semaniak M. Hamberg V. Zhaunerchyk M. Kaminska R.D. Thomas M. af Ugglas M. Larsson W.D. Geppert 《Planetary and Space Science》2012,60(1):102-106
Nitrile ions are abundant in Titan's upper atmosphere and are expected to be lost mainly via dissociative recombination with free electrons. We review in this paper a series of experimental results on the dissociative recombination reactions of nitrile ions known/expected to be present in Titan's upper atmosphere. The experiments were all performed at the heavy ion storage ring CRYRING in Stockholm, Sweden, and the results presented here include information on rate coefficients at electron temperatures relevant for Titan's upper atmosphere as well as information on the product branching fractions of the reactions. We discuss implications of the results for Titan's atmosphere. As an example the presented results support a statement by Krasnopolsky (2009) that nitriles do not degrade to yield N2 again in Titan's atmosphere, indicating that condensation and polymerization with precipitation to the surface are their ultimate fate. 相似文献
920.