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1.
This paper presents data on the properties of coal and fly ash from two coal mines and two power plants that burn single-source coal from two mines in Indiana. One mine is in the low-sulfur (<1%) Danville Coal Member of the Dugger Formation (Pennsylvanian) and the other mines the high-sulfur (>5%) Springfield Coal Member of the Petersburg Formation (Pennsylvanian). Both seams have comparable ash contents (11%). Coals sampled at the mines (both raw and washed fractions) were analyzed for proximate/ultimate/sulfur forms/heating value, major oxides, trace elements and petrographic composition. The properties of fly ash from these coals reflect the properties of the feed coal, as well as local combustion and post-combustion conditions. Sulfur and spinel content, and As, Pb and Zn concentrations of the fly ash are the parameters that most closely reflect the properties of the source coal.  相似文献   
2.
A set of Pennsylvanian coals from the North American coal basins, ranging in vitrinite reflectance from 0.65% to 1.75%, was examined, with special emphasis on the optical properties of pseudovitrinite. The results suggest that pseudovitrinite originates from the same material as telocollinite. Slits in the pseudovitrinite seem to have originated in situ due to low-temperature oxidation of woody material; their opening might have been facilitated by devolatilization during coalification. The dominant orientation of the slits is perpendicular to bedding. The intensity and orientation of the slits in pseudovitrinite could be important factors in predicting coalbed gas extraction from coal.  相似文献   
3.
Anthropogenic eutrophication and spreading anoxia in freshwater systems is a global concern. Little is known about anoxia in earlier historic times under weaker human impact, or under prehistoric natural conditions with different trophic, land cover and climatic regimes. We use a novel approach that combines high-resolution hyperspectral imaging with µ-XRF and HPLC-pigment data, which allows us to assess chloropigments (productivity) and bacteriopigments (anoxia) at seasonal subvarve-scale resolution. Our ~9700 cal a bp varved sediment record from NE Poland suggests that productivity increased stepwise from oligotrophic Early Holocene conditions (until ~9200 cal a bp ) to mesotrophic conditions in the Mid- and Late Holocene. Natural eutrophication was mainly a function of progressing landscape evolution with intense weathering under dense forest and warm-moist climatic conditions. Generally, anoxia increased with increasing productivity. Seasonal anoxia and some multi-decadal periods of meromixis were the common mixing patterns throughout the Holocene except for a period of persisting meromixis between ~5200 and 2000 cal a bp. Anthropogenic deforestation around 400 cal a bp resulted in substantially better lake oxygenation despite high productivity. In this small lake, aquatic productivity and lakeshore forest cover (wind shield) were more important factors controlling oxic/anoxic conditions than Holocene temperature variability.  相似文献   
4.
5.
Indoor air quality attracts great interest. Many dwellings are ventilated naturally. The article presents the gravity system conversion into individual air supply system, which can be equipped with air fan. This solution’s impact on the interior microclimate was analyzed. The proposed solution uses the lower natural ventilation ducts sections, which are not normally used as air supply channels to bring air to the housing. Exhaust grilles were located in the adjacent rooms. Individual air supply system with switched off fan improves indoor air quality insufficiently; however, switching on the device causes a very significant change. A large carbon dioxide concentration reduction (which was used as an air quality indicator) has been confirmed by rigorous statistical analysis, the results of which were presented in the article.  相似文献   
6.
This paper presents the results of studies on plant macroremains found in the upper Turonian of the Folwark Quarry, Opole, Poland, associated with palynological studies of the host rocks. In addition to a few macrofossils (gymnosperm wood, conifer Geinitzia reichenbachii and fern ?Didymosorus) rich sporomorphs (bryophyte, lycopod and fern spores, conifer and angiosperm pollen grains) and marine palynomorphs (mainly dinoflagellate cysts) were recorded. The palynological analysis revealed that the vegetation on the neighbouring land (the East Sudetic Island) in the late Turonian was much more diverse than could be reconstructed based on only macrofossil remains. The latter are taxonomically restricted and dominated by one gymnosperm species (Geinitzia reichenbachii), which make them similar to most neighbouring, coeval Central European assemblages. Its over representation is, thus, a result of taphonomy.  相似文献   
7.
The influence of the North Atlantic on the margins of Europe means the region is particularly sensitive to changes in the ocean–atmospheric system. During the Last Glacial–Interglacial Transition (16–8 cal ka bp ) this system was repeatedly disrupted, leading to a series of abrupt and short-lived shifts in climate. Despite much research, the number and magnitude of these ‘centennial-scale’ events is not well understood. To address this, we expand upon investigations at Quoyloo Meadow, Orkney, Scotland, one of the best chronologically constrained palaeoclimate records in northern Britain. By coupling stable isotope and chironomid fossil analyses with existing data, this study identifies multiple phases of centennial-scale disturbance at: c. 14.0, 11.1, 10.8, 10.5, 10.45 and 10.3 cal ka bp , with the events at 14.0 and 10.3 exhibiting a particularly pronounced cold-climate signature. During the Holocene, the strongest response to climate forcing was at c. 10.3–10.0 cal ka bp , expressed as a two-stage drop in mean July temperatures, a shift in pollen spectra indicative of ‘less-stable’ climatic regimes, and a depletion in δ18O values. We interpret this as the first reliably dated incidence of the ‘10.3-ka event’ in the British Isles and consider the wider impact of this climatic reversal in other Holocene records.  相似文献   
8.
When entering information about changes of settlements in time into a database, we are dealing with direct facts from historical sources and with interpretations. The source information generally relates to an event or situation at a specific time. This means that we only fill in the parts of the timeline with data objects called (partial) manifestations; however, lack of data does not mean that settlement did not exist. It would take a lot of time to interpret and enter missing information manually. In this article we present a database schema, database procedures and algorithms to generate aggregated settlement unit manifestations in an automated way from their partial manifestations. As a result, it is possible to obtain a continuous history of a given settlement so as to present it on a map.  相似文献   
9.
The publication of the European Landscape Convention (2000) had a stimulating effect on the development of both new systems of landscape classification and new methods of their evaluation and mapping. As an example, a new classification of physiognomic landscape types was developed in Poland in 2014. The objectives of the paper are to (1) popularize, on the international scale, the classification of physiognomic landscape types in a new, improved version, (2) present the original method of physiognomic landscape types mapping with the use of the system of basic landscape units, and (3) present the results of testing of the method in the area of the Kazimierz Landscape Park, Poland. In the area of the Kazimierz Landscape Park, 491 basic landscape units were delimited, within which, on the basis of the leading traits of land relief and cover forms, the physiognomic landscape types were identified. Maps of this type can be important tools in implementing the recommendations of the European Landscape Convention. The total number of physiognomic landscape types identified within a specific area can be one of the key indicators of landscape diversity.  相似文献   
10.
A usual event, called anisotropic cosmic-ray enhancement (ACRE), was observed as a small increase (\({\leq}\,5\%\)) in the count rates of polar neutron monitors during 12?–?19 UT on 07 June 2015. The enhancement was highly anisotropic, as detected only by neutron monitors with asymptotic directions in the southwest quadrant in geocentric solar ecliptic (GSE) coordinates. The estimated rigidity of the corresponding particles is \({\leq}\,1\) GV. No associated detectable increase was found in the space-borne data from the Geostationary Operational Environmental Satellite (GOES), the Energetic and Relativistic Nuclei and Electron (ERNE) on board the Solar and Heliospheric Observatory (SOHO), or the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) instruments, whose sensitivity was not sufficient to detect the event. No solar energetic particles were present during that time interval. The heliospheric conditions were slightly disturbed, so that the interplanetary magnetic field strength gradually increased during the event, followed by an increase of the solar wind speed after the event. It is proposed that the event was related to a crossing of the boundary layer between two regions with different heliospheric parameters, with a strong gradient of low-rigidity (\({<}\,1\) GV) particles. It was apparently similar to another cosmic-ray enhancement (e.g., on 22 June 2015) that is thought to have been caused by the local anisotropy of Forbush decreases, with the difference that in our case, the interplanetary disturbance was not observed at Earth, but passed by southward for this event.  相似文献   
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