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1.
Rodney Grapes Sophia Korzhova Ella Sokol Yurii Seryotkin 《Contributions to Mineralogy and Petrology》2011,162(2):253-273
Sekaninaite (XFe > 0.5)-bearing paralava and clinker are the products of ancient combustion metamorphism in the western part of the Kuznetsk
coal basin, Siberia. The combustion metamorphic rocks typically occur as clinker beds and breccias consisting of vitrified
sandstone–siltstone clinker fragments cemented by paralava, resulting from hanging-wall collapse above burning coal seams
and quenching. Sekaninaite–Fe-cordierite (XFe = 95–45) is associated with tridymite, fayalite, magnetite, ± clinoferrosilite and ±mullite in paralava and with tridymite
and mullite in clinker. Unmelted grains of detrital quartz occur in both rocks (<3 vol% in paralavas and up to 30 vol% in
some clinkers). Compositionally variable siliceous, K-rich peraluminous glass is <30% in paralavas and up to 85% in clinkers.
The paralavas resulted from extensive fusion of sandstone–siltstone (clinker), and sideritic/Fe-hydroxide material contained
within them, with the proportion of clastic sediments ≫ ferruginous component. Calculated dry liquidus temperatures of the
paralavas are 1,120–1,050°C and 920–1,050°C for clinkers, with calculated viscosities at liquidus temperatures of 101.6–7.0 and 107.0–9.8 Pa s, respectively. Dry liquidus temperatures of glass compositions range between 920 and 1,120°C (paralava) and 920–960°C
(clinker), and viscosities at these temperatures are 109.7–5.5 and 108.8–9.7 Pa s, respectively. Compared with worldwide occurrences of cordierite–sekaninaite in pyrometamorphic rocks, sekaninaite occurs
in rocks with XFe (mol% FeO/(FeO + MgO)) > 0.8; sekaninaite and Fe-cordierite occur in rocks with XFe 0.6–0.8, and cordierite (XFe < 0.5) is restricted to rocks with XFe < 0.6. The crystal-chemical formula of an anhydrous sekaninaite based on the refined structure is
| \textK0.02 |(\textFe1.542 + \textMg0.40 \textMn0.06 )\Upsigma 2.00M [(\textAl1.98 \textFe0.022 + \textSi1.00 )\Upsigma 3.00T1 (\textSi3.94 \textAl2.04 \textFe0.022 + )\Upsigma 6.00T2 \textO18 ]. \left| {{\text{K}}_{0.02} } \right|({\text{Fe}}_{1.54}^{2 + } {\text{Mg}}_{0.40} {\text{Mn}}_{0.06} )_{\Upsigma 2.00}^{M} [({\text{Al}}_{1.98} {\text{Fe}}_{0.02}^{2 + } {\text{Si}}_{1.00} )_{\Upsigma 3.00}^{T1} ({\text{Si}}_{3.94} {\text{Al}}_{2.04} {\text{Fe}}_{0.02}^{2 + } )_{\Upsigma 6.00}^{T2} {\text{O}}_{18} ]. 相似文献
2.
Quantum yield for the photochemical production of dissolved inorganic carbon in seawater 总被引：2，自引：0，他引：2
The direct photooxidation of coloured dissolved organic matter (CDOM) to dissolved inorganic carbon (DIC) may provide a significant sink for organic carbon in the ocean. To calculate the rate of this reaction on a global scale, it is essential to know its quantum yield, or photochemical efficiency. We have determined quantum yield spectra, φ(λ), (moles DIC/mole photons absorbed) for 14 samples of seawater from environments ranging from a turbid, eutrophic bay to the Gulf Stream. The spectra vary among locations, but can be represented quite well by three pooled spectra for zones defined by location and salinity: inshore φ(λ)=e−(6.66+0.0285(λ−290)); coastal φ(λ)=e−(6.36+0.0140(λ−290)); and open ocean φ(λ)=e−(5.53+0.00914(λ−290)). Production efficiency increases offshore, which suggests that the most highly absorbing and quickly faded terrestrial chromophores are not those directly responsible for DIC photoproduction. 相似文献
3.
Niranjana Nagarajah A.J. Antonette Sophia T. Balasubramanian 《Marine pollution bulletin》1985,16(7):267-271
The behaviour of three intertidal molluscs exposed to water soluble fractions of diesel were studied. The rate of crawling of Cerethidea fluviatilis decreased with an increase in concentration and the animals were completely immobilized at the highest dosage (50%). The burrowing ability of Katelysia opima was found to be suppressed in three different concentrations (25,50 and 75%). Smaller individuals (15–20 mm) appearing to be less sensitive than larger forms (20–25 mm). Byssal thread production in Perna viridis was significantly depressed in all concentrations, except the lowest doses of toxicant (5%), where slight stimulation was observed only with smaller sized individuals (20–30 mm). 相似文献
4.
The effect of sea surface height (SSH) variability is one of the primary factors that limit the accuracy and resolution of altimeter-derived gravity values. We propose a method to estimate the influence of variation of the sea surface height on the accuracy of satellite-derived gravity by simulation technique, with a case study around Indonesian waters. Wederived an Indonesian marine gravity map using the Geosat-geodetic mission (GM). Since most of the area studied is located around coastal and shallow areas, the measurement of SSH of this area is less accurate. To obtain a distribution of SSH variability over the study area, Topex/Poseidon (T/P) data were first processed and assessed. Processing 52 cycles of the Topex/Poseidon data, the root mean square (RMS) of SSH variability for each cycle was found to vary from 1 to 179 cm. Further, for the purpose of estimating the accuracy of altimeter-derived gravity, we derived several levels of Gaussian noise, computed simulation data by adding the Gaussian noise to Geosat data, and determined simulated gravity maps. Based on the distribution of RMS values from T/P data and standard deviation (STD) differences between the simulated and the original gravity maps, we estimated the accuracy of the gravity map. Around Indonesian waters, the accuracy of the gravity map influenced by SSH variation was estimated to be within the range 0.8~93 mgal. 相似文献
5.
Sophia Maalsen 《The Australian geographer》2019,50(3):315-332
ABSTRACTShare housing is changing. Once considered a form of short-term housing and a lifestyle choice for young adults fresh out of the family home, share housing is increasingly playing a broader role into advanced adulthood. Recent work has claimed the emergence of Generation Rent; however, the reconfiguration of housing experiences is illustrated not only by renting but also by an increase in house sharing and the emergence of ‘Generation Share’ within the renting cohort. We know surprisingly little about share housing and its increasingly important role in housing. This paper draws upon exploratory research conducted on share housing in Sydney, Australia, and argues that share housing as traditionally understood is changing. Share housing has a widening demographic and it is driven primarily by economic factors. Despite this, the social affordances offered by share housing are highly valued. Share housing therefore offers us a unique lens into changing housing pathways and values and provokes us to think of ways to produce more socially, economically, and environmentally sustainable housing. 相似文献
6.
Akin Idil Deniz Garnica Sophia S. Robichaud Peter R. Brown Robert E. 《Geotechnical and Geological Engineering》2022,40(3):1187-1200
Geotechnical and Geological Engineering - Post-wildfire erosion and the slope instability issues associated with it are a global problem that can negatively affect transportation corridors, the... 相似文献
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8.
Sophia Kokoni 《Climate Policy》2013,13(3):372-396
A considerable body of academic literature has emerged that addresses methods for consumption-based accounting of greenhouse gas (GHG) emissions as opposed to the territorial approach used under the United Nations Framework Convention on Climate Change (UNFCCC). The consumption-based approach attributes emissions to consumers of final goods and services by accounting for the GHG emissions ‘embedded’ in raw materials and intermediate goods and services. Many authors have advocated the wider adoption of a consumption-based approach. This article does not take one side or another in the consumption-based versus territorial debate. Instead, it explores the extent to which consumption-based thinking has already found practical application by companies and public authorities and assesses the potential for further adoption. The methodologies underlying consumption-based approaches are critically reviewed to note criteria such as accuracy and the timeliness of data generation, which suggest the potential for practical application. A typology of applications is then developed and each category of application is systematically explored citing real-world examples where possible. The article concludes with a discussion of the potential for the wider application of consumption-based approaches and identifies further research needs.Policy relevanceConsumption-based approaches to accounting for GHG emissions are gradually being adopted in the policy domain, albeit in a haphazard way. This article (1) identifies the strengths and weaknesses associated with top-down input–output approaches and bottom-up life cycle assessment approaches to consumption-based accounting in terms of criteria such as accuracy and timeliness of data generation; (2) provides a comprehensive review of actual and proposed applications to date; (3) constructs a taxonomy of applications drawing on the analysis of strengths and weaknesses; and (4) considers the prospects for further application. The article will help policy makers and policy analysts to assess the feasibility and desirability of future applications of consumption-based approaches and address implementation barriers. 相似文献
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Florence Dapples André F. Lotter Jacqueline F.N. van Leeuwen Willem O. van der Knaap Sophia Dimitriadis Daniel Oswald 《Journal of Paleolimnology》2002,27(2):239-248
Schwarzsee is located in the western Swiss Alps, in a region that has been affected by numerous landslides during the Holocene, as evidenced by geological surveys. Lacustrine sediments were cored to a depth of 13 m. The vegetation history of the lake's catchment was reconstructed and investigated to identify possible impacts on slope stability. The pollen analyses record development of forest cover during the middle and late Holocene, and provide strong evidence for regional anthropogenic influence such as forest clearing and agricultural activity. Vegetation change is characterized by continuous landscape denudation that begins at ca. 4300 cal. yrs BP, with five distinct pulses of increased deforestation, at 3650, 2700, 1500, 900, and 450 cal. yrs BP. Each pulse can be attributed to increased human impact, recorded by the appearance or increase of specific anthropogenic indicator plant taxa. These periods of intensified deforestation also appear to be correlated with increased landslide activity in the lake's catchment and increased turbidite frequency in the sediment record. Therefore, this study gives new evidence for a strong influence of vegetation changes on slope stability during the middle and late Holocene in the western Swiss Alps, and may be used as a case study for anthropogenically induced landslide activity. 相似文献