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21.
Słodczyk Elżbieta Pietranik Anna Glynn Sarah Wiedenbeck Michael Breitkreuz Christoph Dhuime Bruno 《International Journal of Earth Sciences》2018,107(6):2065-2081
International Journal of Earth Sciences - The Polish Lowlands, located southwest of the Teisseyre–Tornquist Zone, within Trans-European Suture Zone, were affected by bimodal, but dominantly... 相似文献
22.
B. Gawron T. Białecki 《International Journal of Environmental Science and Technology》2018,15(7):1501-1508
It is forecast that in the future, alternative fuels derived from non-petroleum sources will become the basic propellant for turbine aircraft engines. Currently, five types of aviation turbine fuel containing synthesized hydrocarbons are certified and accepted, and allow adding a maximum of 50% of synthetic component to conventional fuel. The experimental performance and the emission characteristics of a turbojet engine were investigated in this paper. The studies were conducted with the use of a miniature turbojet engine, which is the main component of a laboratory test rig. The test rig is an interesting solution for engine research, due to the fact that studies concerning full-scale aircraft engines are very complex and expensive. The literature of the subject contains many papers using small-scale turbojet engines for testing alternative fuels. However, most of them concern components of fuels, e.g. biodiesel, butanol, which do not have direct application in aviation. Two different fuel samples, a conventional Jet A-1 fuel and a blend of 48% synthesized paraffinic kerosene from hydroprocessed esters and fatty acids process with Jet A-1 were tested. This process is one of the routes of producing alternative fuel for aviation, approved by ASTM standard. The test rig studies were performed according to a specific profile of engine test, which models different modes of a turbojet engine’s operation. The obtained results are compared in relation to the results for neat Jet A-1 fuel and then discussed. 相似文献
23.
J. Tomaszewska P. Smektała I. Zgłobicka J. Michalski K. J. Kurzydłowski P. Krzemiński C. Escudero-Oñate 《International Journal of Environmental Science and Technology》2018,15(9):1831-1842
Due to its harmful impact on human health, the presence of heavy metals, metalloids and other toxic pollutants in drinking or irrigation water is a major concern. Recent studies have proved that nanosized adsorbents are significantly more effective than their microsized counterparts. Particular attention has been given to nanocomposites with nanoadsorbents embedded in matrixes that could provide stability to the material and contribute to eliminating problems that may appear when using conventional granular systems. This study presents the preparation of a novel hybrid filter from a commercially available polypropylene (PP) non-woven fabric matrix modified with multiwall carbon nanotubes (MWCNT) and iron oxy(hydroxide) nanoparticles, and its use in the removal of As(III). A Box–Behnken statistical experimental design has been chosen to explore relevant variables affecting the filter performance: (1) As(III) concentration, (2) pH and (3) sorbent dose. From an As(III) concentration of 10 mg L?1, at pH 6.5 and with a sorbent dose of 5 g L?1, the PP filter modified with MWCNT removes 10% of the initial metalloid concentration, reaching a capacity of 0.27 mg g?1. After modification with iron oxy(hydroxide), the performance of the material is largely enhanced. The filter, under the same conditions, removes 90% of the initial As(III) concentration, reaching a capacity almost tenfold higher (2.54 mg g?1). This work demonstrates that the developed hybrid filter is effective toward the removal of As(III) in a wide range of pHs. A cubic regression model to compute the removal of the filter as a function of pH and sorbent dose is provided. 相似文献
24.
Bartosz J. Płachno Agata Jurkowska Grzegorz Pacyna Elżbieta Worobiec Przemysław Gedl Ewa Świerczewska-Gładysz 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):159-170
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
25.
Ashworth Luisa Kinnaird Judith Ann Nex Paul Andrew Martin Erasmus Rudolph Marthinus Przybyłowicz Wojciech Józef 《Mineralogy and Petrology》2018,112(6):753-765
Mineralogy and Petrology - Mineralized NYF and LCT pegmatites occur throughout the northeast-trending Neoproterozoic Damara Belt, Namibia. Mineralization in the pegmatites varies geographically,... 相似文献
26.
Dumańska-Słowik Magdalena Pieczka Adam Natkaniec-Nowak Lucyna Kunecki Piotr Gaweł Adam Heflik Wiesław Smoliński Wojciech Kozub-Budzyń Gabriela 《Mineralogy and Petrology》2018,112(3):381-392
Mineralogy and Petrology - Supergene Mg-enriched erythrite, with an average composition (Co2.25Mg0.58Ni0.14Fe0.04Mn0.02 Zn0.02) (As1.97P<0.01O8)·8H2O, accompanied by skutterudite,... 相似文献
27.
Rene PUTISKA Marian MARSCHALKO Isik YILMAZ Dominik NIEMIEC CHENG Xianfeng Ivan DOSTAL Jan KUBAC 《《地质学报》英文版》2021,95(5):1763-1770
This article presents a research study of complex limestone karst engineering-geological conditions in the municipality Valaská near Banská Bystrica in Slovakia. The aim of the study is to demonstrate the impossibility of spatial identification of cave spaces using surface geophysical methods due to the specific engineering-geological conditions of a thick surface layer of anthropogenic fill containing highly heterogeneous anthropogenic material. Its maximum thickness is 3 m. Another specificific condition of the study area is its location in the built-up area, due to which the applicability of geophysical methods was limited. The article contains methodological recommendations to be used in analogous geological conditions with karst structures topped with anthropogenic fill, which complicates the identification of cave spaces. The recommended solution herein is the identification of the cave system using underground mapping of the karst and its projection onto the surface for which surface geophysical methods have been combined. 相似文献
28.
Burrows of the thalassinidean shrimps Neaxius acanthus and Corallianassa coutierei are striking aspects in tropical seagrass beds of the Spermonde Archipelago, Indonesia. Burrow construction, behaviour, burrow type and associated commensal community were investigated to clarify the ecological role and food requirements of these shrimps and their commensals. Gut content analysis and stable-isotope data were used to unravel the food sources and the trophic interactions among the commensal community.Individuals of Neaxius acanthus were caught on Bone Batang Island. In narrow aquaria filled with sediment they constructed burrows resembling those found in the field. During burrow construction and maintenance only little sediment was brought to the surface, most was sorted and compacted to create a distinct lining. Maintenance work by single shrimps typically took about 5 min, after which the shrimp walked up to the entrance and rested for a similar period of time. There were no differences in behaviour between day and night. Intrasexual encounters inside the burrow were characterised by a high level of aggression and all resulted in one participant being driven out of the burrow. Intersexual encounters led to coexistence with both animals taking turns in burrow maintenance and guarding the entrance. Offered seagrass leaves were pulled underground, cut into pieces and eventually integrated into the lining. Burrows of Corallianassa coutierei resembled a deep U-shape. Chambers branching off halfway down and at the deepest point contained seagrass fragments. All steep parts of the burrow were lined similar to burrows of N. acanthus.No commensals were found associated with Corallianassa coutierei. However, burrows of Neaxius acanthus in the field typically contained a pair of shrimps, up to 8 individuals of the commensal bivalve Barrimysia cumingii and large numbers of gammarid amphipods. Other animals found associated with the burrow were the goby Austrolethops wardi, a palaemonid shrimp species and two species of tube-building polychaetes, one of which was also found as an epibiont on N. acanthus.Stable-isotope and gut content analyses indicate that the diet of Neaxius acanthus, its commensal Austrolethops wardi, and Corallianassa coutierei is mainly derived from detrital seagrass leaves, with a potential contribution of sediment organic matter and seagrass epiphytes. In contrast the isotopic signature of Barrimysia cumingii suggests the presence of symbiotic sulphide metabolism bacteria. This study underlines that, besides their interactions with the surrounding ecosystem, thalassinid shrimp burrows play an important role as a sub-habitat with a unique associated fauna. 相似文献
29.
The main purpose of the research is to achieve fully automated approach for supplying multi-resolution databases with linear objects in each scale. Moreover, the proposed solutions maintain the repeatability and accuracy of output data wherever possible according to the input scale. These properties are achieved by keeping the minimal object dimensions as well as the appropriate data pre-processing, based on the classification of source points. The classification distinguishes three classes of points: constant (unchangeable), temporary, and inherited. These classes build a structure of cartographic control points. Based on these solutions, the authors proposed an algorithm for linear object simplification based on minimal object dimensions and cartographic control points. It was also confirmed that the simplification between constant points does not cause geometry discrepancies in relation to the global simplification of the whole line. 相似文献
30.
We conducted acoustical surveys with a horizontal beam transducer to detect fish and with a vertical beam transducer to detect depth and macrophytes in two typical shallow lakes along the middle and lower reaches of the Changjiang(Yangtze) River in November 2013. Both lakes are subject to active fish management with annual stocking and removal of large fish. The purpose of the study was to compare hydroacoustic horizontal beam estimates with fish landings. The preliminary results show that the fish distribution patterns dif fered in the two lakes and were af fected by water depth and macrophyte coverage. The hydroacoustically estimated fish biomass matched the commercial catch very well in Niushan Lake, but it was two times higher in Kuilei Lake. However, acoustic estimates included all fish, whereas the catch included only fish 45 cm(smaller ones were released). We were unable to determine the proper regression between acoustic target strength and fish length for the dominant fish species in the two lakes. 相似文献