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61.
Maria Mastalerz Wilfrido Solano-Acosta Arndt Schimmelmann Agnieszka Drobniak 《International Journal of Coal Geology》2009,79(4):167-174
This paper investigates changes in the high-volatile bituminous Lower Block Coal Member from Indiana owing to moisture availability and oxidation in air at ambient pressure and temperature over storage time. Specifically, it investigates changes in chemistry, in surface area, and pore structure, as well as changes in methane and carbon dioxide adsorption capacities. Our results document that the methane adsorption capacity increased by 40%, whereas CO2 adsorption capacity increased by 18% during a 13-month time period. These changes in adsorption are accompanied by changes in chemistry and surface area of the coal.The observed changes in adsorption capacity indicate that special care must be taken when collecting samples and preserving coals until adsorption characteristics are measured in the laboratory. High-pressure isotherms from partially dried coal samples would likely cause overestimation of gas adsorption capacities, lead to a miscalculation of coal-bed methane prospects, and provide deceptively optimistic prognoses for recovery of coal-bed methane or capture of anthropogenic CO2. 相似文献
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Agnieszka Zwirowicz-Rutkowska 《Earth Science Informatics》2017,10(3):369-382
There is a demand for evaluation of spatial data infrastructures (SDIs), to justify and monitor the relations between investments in SDI initiatives and the results obtained. It is also essential to pay particular attention to identifying user communities, and eliciting their assessment of effects deriving from an SDI. The paper introduces a concept of a multi-criteria method which allows to assess effectiveness of the SDI from the user perspective. The application of the proposed method in the Polish Spatial Data Infrastructure (PSDI) and its main access point to spatial data and services called ‘Geoportal 2’ as well as two groups of the national geoportal”s users (spatial planners and land surveyors) presents its potential. The total scores for the Geoportal 2 indicated the investment has potential and is quite effective, although some components of the PSDI (e.g. main access point, datasets, network services, software, hardware, procedures) may need improvements and additional analyses in the future. The contribution of this paper is the multi-criteria method which enables the analysis of outcomes, benefits (impacts) and business value of using SDI business project’s artifacts (outputs) considering the following dimensions: information and support provided, use process, user organizational performance, strategic alignment and business impact on user enterprise. 相似文献
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James C. Hower Maria Mastalerz Agnieszka Drobniak Jeffrey C. Quick Cortland F. Eble Matthew J. Zimmerer 《International Journal of Coal Geology》2005,63(3-4):205-227
With pending regulation of mercury emissions in United States power plants, its control at every step of the combustion process is important. An understanding of the amount of mercury in coal at the mine is the first step in this process. The Springfield coal (Middle Pennsylvanian) is one of the most important coal resources in the Illinois Basin. In Indiana and western Kentucky, Hg contents range from 0.02 to 0.55 ppm. The variation within small areas is comparable to the variation on a basin basis. Considerable variation also exists within the coal column, ranging from 0.04 to 0.224 ppm at one Kentucky site. Larger variations likely exist, since that site does not represent the highest whole-seam Hg nor was the collection of samples done with optimization of trace element variations in mind. Estimates of Hg capture by currently installed pollution control equipment range from 9–53% capture by cold-side electrostatic precipitators (ESP) and 47–81% Hg capture for ESP + flue-gas desulfurization (FGD). The high Cl content of many Illinois basin coals and the installation of Selective Catalytic Reduction of NOx enhances the oxidation of Hg species, improving the ability of ESPs and FGDs to capture Hg. 相似文献
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Krystyna Szeroczyńska Andrzej Tatur Jan Weckström Michał Gąsiorowski Agnieszka M. Noryśkiewicz Elwira Sienkiewicz 《Journal of Paleolimnology》2007,38(1):25-47
A 2.5-m-long sediment core was retrieved from Lake Somaslampi, a small lake located in a kame field on the north slope of
the Scandes Mountains in Finnish Lapland. Holocene environmental changes were inferred from the lithological, geochemical,
pollen, diatom and Cladocera records stored in the lake sediment. The chronology was based on six radiocarbon AMS dates supported
by a palynological control chronology. The sediment profile consists of a glacial sedimentary sequence truncated by a lacustrine
one. A hiatus, tentatively correlated with climate cooling and advances of glaciers during the 8.2 ka yrs BP “Finse cooling
Event”, occurs between these sequences. The glacial sequence was composed of fluvioglacial clastics, smoothly changing into
glacio-lacustrine diatomaceous ooze deposited in a meromictic proglacial lake that covered the kame field. The meromixis was
probably caused by the greater depth of the lake, the extended ice-cover, and the microbial mats covering large areas of the
lake bottom. A distinct change in the biota of the glacio-lacustrine sediments indicates higher trophic conditions than during
deposition of the fluvioglacial clastics. The late-Pleistocene vegetation was characterised by subarctic birch tundra vegetation
(Betula–Salix–Ericaceae) with low biodiversity gradually changing to Betula–Pinus dominance in the early Holocene. The lake was deep and had a diatom inferred pH ~ 7 indicated also by the dominance of planktonic
Cladocera.
The base of the lacustrine sediment sequence (6,650–6,300 cal. BP) consisted of loess-rich sediment indicating an increase
in eolian activity. This is also supported by the pollen record, which is dominated by more long-distant taxa such as Alnus and Pinus, and by the increased C/N ratio of the sediment. After the initial meromictic phase of the lake, an abrupt lowering of the
water level occurred. Lake Somaslampi was isolated from the larger Pre-Lake Somas basin and became holomictic, shallow, much
warmer and more productive, until the deterioration of climate around 3,000 yr BP and the increased input of clastics from
the tundra soils. The vegetation followed the general climatic trend by gradually changing from the dominance of Betula and Pinus to the dominance of more tundra-related vegetation like Poaceae and Cyperaceae. However, the higher frequencies of planktonic
Cladocera and centric diatoms in the most recent sediments indicates higher trophic conditions, increased turbulence and a
prolonged ice-free period, which can possibly be linked to the recent climate warming especially in areas of higher altitude
and latitude. 相似文献
65.
Agnieszka Drobniak Maria Mastalerz John Rupp Nathan Eaton 《International Journal of Coal Geology》2004,57(3-4):265-282
The Seelyville Coal Member of the Linton Formation in Indiana potentially contains 0.03 trillion m3 (1.1 TCF) of coalbed gas. The gas content determined by canister desorption technique ranges from 0.5 to 5.7 cm3/g on dry ash free basis (15.4 to 182.2 scf/ton). The controls on gas content distribution are complex, and cannot be explained by the coal rank alone. Ash content and the lithology of the overlying strata, among other factors, may influence this distribution. 相似文献
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The occurrence and distribution of freshwater snails in a heavily industrialised region of Poland (Upper Silesia) 总被引：1，自引：0，他引：1
Anthropogenic water bodies namely fish ponds, clay pits, sand pits, dam reservoirs or mining subsidence pools are the characteristic feature of Upper Silesian landscape. In the study, the gastropod communities occurring in 296 anthropogenic water bodies were discussed in relation to their distribution in macroregions of Upper Silesia, role in industrialised and urbanised environment and the significance for regional biodiversity.In period 1998–2002, 31 freshwater gastropod species were found in the study area. It is noteworthy, that the anthropogenic water habitats of Upper Silesia provide a refuge for several rare and vulnerable species, among them e.g. Anisus leucostoma (Millet, 1813), Gyraulus rossmaessleri (V. Auerswald, 1852) and Hippeutis complanatus (Linnaeus, 1758). 相似文献
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Agnieszka I. Olbert Michael HartnettTomasz Dabrowski Uwe Mikolajewicz 《Continental Shelf Research》2011,31(13):1343-1356
The western Irish Sea gyre (WISG) is a cyclonic baroclinic flow around a dome of stagnant water which develops each year during the heating season in the western Irish Sea. Research was carried out to determine long-term changes in the strength of stratification within WISG and associated changes in the gyre structure, circulation patterns and retentive properties. Model simulations were carried out for the 58-year period 1951-2008. The characteristics of the gyre were quantified by means of potential energy anomaly (PEA), measuring the strength of stratification, and total kinetic energy (KE), reflecting the strength of cyclonic circulation. Additionally, long-term changes in flushing rates within the gyre were assessed.Results show that stratification in the western Irish Sea consistently begins to develop in March, increases linearly from April till June, peaks at the beginning of July and remains at close to maximum level throughout the month of July, before a start of a sharp decline at the beginning of August. The strength of stratification is significantly correlated with averaged summer air temperatures and summer wind speeds. Trend analysis of PEA shows an increase in the stratification strength over the period considered; the increase of PEA peak value is accompanied by a shortening of the gyre duration and a delay in the timing of the peak value. There is also an increasing trend in the KE value, showing that the thermal stratification plays a crucial role in the hydrography of the region. Flushing analysis shows that the stronger the stratification the lower the residence time and thus the faster the removal of the material from the western Irish Sea. Residence time within WISG shortens on average by 8 days over the 58-year period. 相似文献