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1.
The irreversible water–rock mass exchanges leading to the production of the Fiume Grande valley (Calabria, Italy) stream waters
and groundwaters, starting from local rainwaters, were simulated through reaction path modeling in reaction progress (stoichiometric)
mode. The simulations assumed bulk dissolution of a phyllitic rock and calcite and precipitation of gibbsite, kaolinite, amorphous
silica, illite, a smectite solid mixture, a hydroxide solid mixture, and a trigonal carbonate solid mixture. The analytical
contents of major and trace elements in stream waters and groundwaters were satisfactorily reproduced. However, further investigations
are necessary to clarify the fate of As in this natural systems.
相似文献
Rosanna De RosaEmail: |
2.
Using density functional simulations, within the generalized gradient approximation and projector-augmented wave method, we study structures and energetics of CaSiO3 perovskite in the pressure range of the Earths lower mantle (0–150 GPa). At zero Kelvin temperature the cubic
CaSiO3 perovskite structure is unstable in the whole pressure range, at low pressures the orthorhombic (Pnam) structure is preferred. At 14.2 GPa there is a phase transition to the tetragonal (I4/mcm) phase. The CaIrO3-type structure is not stable for CaSiO3. Our results also rule out the possibility of decomposition into oxides.
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Daniel Y. JungEmail: Phone: +41-44-6323744Fax: +41-44-6321133 |
3.
Craig W. Morgan Graham M. Kent Gordon G. Seitz Michaela Novak 《Hydrogeology Journal》2008,16(5):981-994
A hydrogeologic model that has been used by many researchers and consultants to describe an area of South Lake Tahoe, California,
USA impacted by MTBE contamination describes a relatively homogeneous unconfined aquifer comprised of poorly sorted glacial
outwash deposits, within which water-supply wells are able to exert significant alteration in natural groundwater flow. A
re-examination of the area’s hydrogeology is presented, which supports a layered heterogeneous aquifer system constructed
of alternating fine and coarser-grained glacio-lacustrine depositional units. This re-evaluation was accomplished through
a review of lithologic logs across an area of approximately 1 km2, combined with observations of significant hydraulic head differences and knowledge of the depositional environments controlled
by Pleistocene Lake Tahoe high stands. Many of the fine-grained units observed at depths from 6 to 15 m, although relatively
thin, are generally continuous and serve as significant barriers to groundwater flow. The vertical migration of contamination
across these fine-grained units to deeper groundwaters was facilitated by cross-screened monitoring wells installed as part
of site investigation activities. This conclusion highlights the importance of geologic characterization and proper monitoring
well construction at contaminated site investigations.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
相似文献
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Michaela NovakEmail: |
4.
The advent of the Virtual Observatory has begun an evolution in the space physics data environment. A number of nascent and
discipline specific Virtual Observatories have started to emerge with an emphasis on data search and retrieval. As this new
data environment takes shape an emphasis will be placed on interdisciplinary communication in attempts to address large scale
and global problems. To this end we formulate the development of a query language to facilitate Virtual Observatory to Virtual
Observatory communication. Furthermore, we outline the goals of such a language, how it would work and how existing community
efforts can be leveraged to speed the development of this query language.
相似文献
T.W. NarockEmail: |
5.
A commented translation of the paper by C.W. Correns and W. Steinborn on crystallization pressure 总被引:1,自引:0,他引:1
Crystallization of salts is recognized to be a major factor of the degradation of porous materials such as stone and concrete.
On the theoretical side, there is now general acceptance about the thermodynamic origin of this phenomenon. However, on the
experimental side, there are only scarce quantitative data. In this respect, the reference work par excellence is that of Correns (Discuss Faraday Soc 5:267–271, 1949) who shows a good correlation between calculated and measured crystallization pressures. However, concerns about both the
thermodynamic derivation and the experimental conditions raise the question about why Correns could have obtained such a good
correlation. This issue is discussed extensively in this paper which is organized as a commented translation of a former paper
by Correns, co-authored by Steinborn, and that is much richer in experimental details.
相似文献
Robert J. FlattEmail: |
6.
This paper presents an examination of the timescale of phase transition behaviour of a series of salts known to cause damage
to wall paintings and other cultural property. The rate of deliquescence and crystallisation of single salts (nitromagnesite
and halite) under different RH regimes, and the extent to which this was affected when mixed with other salts (niter, nitratite
and gypsum), was investigated. The study was conducted using simple conventional techniques (mass measurements over time)
and also using an innovative new method: timelapse video imaging with online data annotation. The results demonstrate the
synergy gained from combining video imaging with environmental data in reference to time in the study of salt phase changes:
where it revealed new information concerning the kinetics of deliquescence and crystallisation. The implications of these
results for the implementation of environmental control measures within historic buildings are discussed.
相似文献
Alison SawdyEmail: |
7.
Giorgio Hadi Curti 《GeoJournal》2009,74(3):201-208
Ostensibly, subtitles in films serve as linguistic approximations of meaning. Expectedly then, much of the debate surrounding
subtitling has been concerned with representational accuracy, fidelity and authenticity. In this article I argue that by encountering
subtitles as affective bodily expressions, as opposed to approximate representations of pre-existent meanings or intentions,
filmic experiences may be(come) transformed and differently transformational. As a result, meaning and accuracy in subtitles
as superimposed signifiers or static representations become secondary to subtitles as spatially affective- and expressive-movements
intimately part of filmic scapes. The creative use of subtitling in Bekmambetov’s Russian language film Night Watch (Nochnoy dozor; 2006 [2004]) is discussed.
相似文献
Giorgio Hadi CurtiEmail: |
8.
Metal cycling via physical and chemical weathering of discrete sources (copper mines) and regional (non-point) sources (sulfide-rich shale) is evaluated by examining the mineralogy and chemistry of weathering products in Great Smoky Mountains National Park, Tennessee, and North Carolina, USA. The elements in copper mine waste, secondary minerals, stream sediments, and waters that are most likely to have negative impacts on aquatic ecosystems are aluminum, copper, zinc, and arsenic because these elements locally exceed toxicity guidelines for surface waters or for stream sediments. Acid-mine drainage has not developed in streams draining inactive copper mines. Acid-rock drainage and chemical weathering processes that accompany debris flows or human disturbances of sulfidic rocks are comparable to processes that develop acid-mine drainage elsewhere. Despite the high rainfall in the mountain range, sheltered areas and intermittent dry spells provide local venues for development of secondary weathering products that can impact aquatic ecosystems.Electronic Supplementary Material Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material.
相似文献
Jane M. HammarstromEmail: Phone: +1-703-6486165Fax: +1-703-6486252 |
9.
Remote sensing and GIS based determination of groundwater dependent ecosystems in the Western Cape, South Africa 总被引:4,自引:0,他引:4
Finding the location of groundwater dependent ecosystems (GDEs) is important in determining the extent of restrictions that
need to be placed upon the abstraction of groundwater. Remote sensing was combined with geographical information system (GIS)
modelling to produce a GDE probability rating map for the Sandveld region, South Africa. Landsat TM imagery identified the
areas indicating the probable presence of GDEs and GIS assisted in their delineation. Three GIS models were generated: a GIS
model predicting landscape wetness potential (LWP model) based on terrain morphological features; the LWP model was modified
to highlight groundwater generated landscape wetness potential (the resulting GglWP model); and a groundwater elevation model
was interpolated, combining groundwater level measurements in boreholes in the region with digital elevation model data. Biomass
indicators generated from Landsat were classified and combined with the GIS models, followed by field verification of riverine
and wetland GDEs. The LWP model provided the most accurate results of the three models tested for GDEs in this region.
相似文献
Zahn MünchEmail: |
10.
A comparison of TRMM to other basin-scale estimates of rainfall during the 1999 Hurricane Floyd flood 总被引:5,自引:2,他引:3
The volumetric rainfall attributed to Hurricane Floyd in 1999 was computed for the bulk of the Tar, Neuse, and Cape Fear River
Basins in eastern North Carolina, USA from the Tropical Rainfall Measuring Mission (TRMM) Multi-Satellite Precipitation Analysis
(TMPA) research product, and compared with volumes computed using kriged gauge data and one centrally located radar. TMPA
showed similar features in the band of heaviest rainfall with kriged and radar data, but was higher in the basin-scale integrations.
Furthermore, Floyd’s direct runoff volumes were computed and divided by the volumetric rainfall estimates to give runoff coefficients
for the three basins. The TMPA, having the larger storm totals, would suggest greater infiltration during Floyd than the gauge
and radar estimates would. Finally, we discuss a concept for adjusting the United States Department of Agriculture Natural
Resources Conservation Service rainfall-runoff model when predicting discharge values from real-time TMPA in ungauged river
basins.
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Scott CurtisEmail: |
11.
An increasingly utilized strategy for expanding conservation in the developing world has been the promotion of protected areas
that supersede national borders. Alternatively known as transfrontier biosphere reserves, transfrontier or transboundary conservation
areas, or Peace Parks, these protected areas are aggressively advanced by conservation agencies for their purported ecological
and economic benefits. This article provides a comparative assessment of two case studies to understand the various impacts
of transboundary conservation. The Great Limpopo Transfrontier Park, which unites protected areas in South Africa, Mozambique
and Zimbabwe, is contrasted with efforts to protect jaguars along the United States–Mexico border. We argue that while these
cases are promising for the purposes of biodiversity protection, they demonstrate that transboundary conservation can minimize
political context, contributes to the hegemony of international conservation agendas, and remains closely linked to economic
neoliberalism and decentralization in the developing world.
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Brian KingEmail: |
12.
Southeast Asian countries suffer from severe coastal hazards each year. A large number of these countries are incurring consequential
costs that impact their national economies. It is crucial, therefore, to analyze the impact of such hazards on their economic
development and provide a solid basis for future development strategies. The purpose of this paper is to assess the relationship
between the economic development and the losses from coastal disasters, and to identify both the impact of hazards on the
development, as well as the function of such development on the resilience to hazards. The data envelopment analysis (DEA)
method is employed to build the assessment models. Data from 1995 to 2005 from eight Southeast countries are analyzed using
the DEA models. A set of “resilience index” of these countries are concluded from the results. It is found that the economic
development does not contribute to the strengthening of national resilience to coastal hazards. Inappropriate development
could even impair the resilience. Additionally, the resilience to coastal hazards is impacted by various factors such as the
allocation of resources and external assistance. From the analysis, a clear image is gained of the interaction between economic
development and coastal hazards, which provides a basis for future development strategies.
相似文献
Yi-Ming WeiEmail: Email: |
13.
Using resistivity measurements for dam safety evaluation at Enemossen tailings dam in southern Sweden 总被引:1,自引:0,他引:1
Internal erosion is a major reason for embankment dam failures. Resistivity measurements is an essentially non-destructive technique, which may have the possibility of detecting internal erosion processes and anomalous seepage at an early stage before the safety of the dam is at stake. This paper presents results from part of a dam safety investigation conducted at the Enemossen tailings dam in southern Sweden. Longitudinal resistivity sections, 2D measurements along the dam crest, provided an overview of the whole dam and served to detect anomalous zones. In selected areas, additional cross-sectional 2D surveys gave detailed information about the geo-electrical situations in the embankments. This information is valuable for similar investigations as information about resistivity in embankment construction material is scarce. Known problem areas were associated with low resistivities, even though the resistivity measurements alone did not provide enough information to confidently come to a decision about the status of the dams.
相似文献
S. JohanssonEmail: |
14.
A Double Solid Reactant Method was elaborated from a suggestion of Marini (Geological sequestration of carbon dioxide: Thermodynamics,
kinetics, and reaction path modeling. Developments in Geochemistry, Elsevier, Amsterdam, 2007) to simulate the release of
trace elements during the progressive dissolution of solid phases. The method is based on the definition, for each dissolving
solid, of both an entity whose thermodynamic and kinetic properties are known (either a pure mineral or a solid mixture) and
a special reactant, that is, a material of known stoichiometry and unknown thermodynamic and kinetic properties. The special
reactant is utilised to take into account the concentrations of trace elements in the dissolving solid phase. In this communication,
the influence of several trace elements on the ΔG
f
o, ΔG
r
o and log K of the minerals considered by Lelli et al. (Environ Geol, 2007) and Accornero and Marini (Geobasi, 2007a; Proceedings of
IMWA symposium, Cagliari, 27–31 May 2007b) was evaluated assuming ideal mixing in the solid state. These effects were found
to be negligible for albite and the leucite–latitic glass, limited for muscovites and chlorites, and slightly more important
for apatites. These influences become progressively higher with increasing concentration of trace elements in these minerals.
Based on these deviations in thermodynamic parameters, special reactants should not include oxide components with molar fractions
higher than 0.003.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
相似文献
Luigi MariniEmail: |
15.
Perception of flood risk in Danube Delta,Romania 总被引:1,自引:1,他引:0
For exposed and vulnerable communities, the perception of natural risk is an essential link in the analysis of man–environment
coping relationship and also an important parameter in the quantification of complex vulnerability as a central predictive
variable in the risk equation. The topic of flood risk in related perception is of considerable interest, as some recently
published papers have proven (Messner and Meyer 2005, 2006; Raaijmakers et al. 2008). The aim of the current study is to reveal the conscious and unconscious attitudes towards the flood risk for the inhabitants
of the Danube Delta/Romania. These attitudes, defined by different degrees of psychological vulnerability, represent the background
for a series of psycho-behavioural patterns that generate certain adjustment mechanisms and strategies. Application of a specially
designed questionnaire and the statistical analysis of the results revealed two psychological factors as essential in establishing
the psychosocial vulnerability degree of the interviewed subjects: (i) an internal control factor and (ii) an external control
factor. The persons characterized by inner control have a significantly reduced general anxiety level in comparison to individuals
with the control factor placed externally. As confidence diminishes, it increases the tendency of the individual to rely on
the external factors for support and security. The lack of resources (indicating lower resilience) and mistrust in the support
given emphasizes non-adaptive behaviours.
相似文献
Iuliana ArmaşEmail: |
16.
John Finn 《GeoJournal》2009,74(3):191-200
After more than three decades of isolation from the West and a paralyzing economic crisis in the early 1990s, Cuba is increasingly
globally active in both cultural and economic realms. In this paper I use Bourdieu’s (The fields of cultural production, 1993)
fields of cultural production as a general frame through with to inspect the commercialization of Cuban music. Through a case
study with Juan de Marcos Gonzalez, the creator of the Buena Vista Social Club, I explore the dialectical relationship of
music as an expression of cultural and a cultural asset, and at the same time a commodity for the international market. I
show that de Marcos uses his position between the international music industry and the local music scene in order to preserve
cultural authenticity and survive economically. In doing so he challenges the all-to-typical place of the artist in the contested
space of cultural production between the West and the Third World.
相似文献
John FinnEmail: |
17.
With the global container population exceeding 25 million TEU (Twenty-foot Equivalent Unit) and the annual production of new
boxes exceeding 3 million TEU it is estimated that around 1.5 million TEU of empty containers are sitting in yards and depots
around the world waiting for use. Although utilization rates have improved since 2004, container utilization depends on the
very dynamic nature of container transportation, and the container building and leasing industries. Owing primarily to the
chronic trend of increasing trade imbalances across the oceans, and despite recent trends along some trade routes, the empty
container management problem has become a major issue for the container shipping industry during the last decade. This paper
examines and analyzes empty container logistics at a global, interregional, regional and local level. Special consideration
is given to key factors affecting the empty container logistics management and strategies implemented by ocean carriers and
other stakeholders to better manage empty containers.
相似文献
Maria BoileEmail: |
18.
Economic and social development indicators suggest that the small West African state of Sierra Leone is among the poorest
countries in the world. Sierra Leone’s economy and quality of life deteriorated rapidly during a decade of political instability
and civil war in the 1990s, when many people fled their homes and abandoned their livelihoods due to the rebel insurgency.
This paper examines the post-war reconstruction scenario in Sierra Leone and presents recent evidence from two rural communities
in the Eastern Province that were badly affected by the conflict. The paper considers the links between the farming and diamond
mining sectors, which, despite severe dislocation during the conflict period, have proved to be remarkably resilient. It is
argued that seasonal labour mobility associated with this dual economy has not only continued to be a key ingredient in sustaining
livelihood portfolios, but is actually an essential pre-condition for the creation of an enabling environment for sustainable
post-conflict return.
相似文献
Tony BinnsEmail: |
19.
Ethnic coexistence in a pluralistic campus environment 总被引:1,自引:0,他引:1
Emile Kok-Kheng Yeoh 《GeoJournal》2006,66(3):223-241
In Malaysia, ethnic segregation seems to have grown more and more pronounced at all levels of education, which may have in
the main contributed to increasing occupational segregation by ethnicity when the graduates left to join the job market. Such
trends may be disturbing given the effort the country has put in to promote interethnic understanding and reduce interethnic
economic disparity since 1970. By critically investigating the dynamics of ethnic coexistence in the microcosm of the university
campus environment, this paper provides statistical evidence to show how far the country has progressed in terms of ethnic
relations since the watershed events of May 13, 1969; to what extent Malaysian multiethnic society is different now compared
to the unmistakable racial “corporateness” and interethnic “separateness” that Furnivall observed in his classic study of
1948; and in what ways ethnic relations have been reshaped by three decades of affirmative action policies and the form of
ethnic democracy adapted for this unique society.
相似文献
Emile Kok-Kheng YeohEmail: |
20.
Krieger’s conceptualization and measurement of discrimination and internalized oppression in studies of adverse health outcomes 总被引:1,自引:1,他引:0
Embodiment is a central concept in Krieger’s ecosocial theory, and is said to be of relevance to the understanding of the
relationship between social conditions and a variety of adverse health outcomes. The most detailed empirical investigation
of this in Krieger’s work is to be found in her studies of the relationship between racial discrimination and high blood pressure.
Of especial relevance here is the idea of internalized oppression which is said to explain the observed association between
self-reports of no racial discrimination and increased levels of blood pressure among working-class African Americans. Here
we critically examine the empirical evidence pertaining to internalized oppression. Specifically, we focus on the measurement
of the construct and the quality of the empirical evidence that has been presented in support of the hypothesis that there
is an association between internalized oppression and adverse health outcomes. We argue that the validity of the concept has
yet to be established and that the available data linking it to poor health outcomes are open to alternative explanations,
notably measurement error and misclassification.
相似文献
Eugenia CondeEmail: |