Textural properties vs. CEC and EGME retention of Na–X zeolite prepared from fly ash at room temperature     

Arkadiusz Derkowski  Wojciech Franus  Halina Waniak-Nowicka  Adriana Czímerová 《International Journal of Mineral Processing》2007

Zeolite Na–X (FAU type) was synthesized from F-class fly ash in simple and economical way. Several months of storage of fly ash in NaOH solution, at room temperature, without any prior treatment, results in the production of material with ca. 50% content of Na–X zeolite. The most efficient reaction takes place at (OH)⁻ activity of 0.1–0.15 mol (OH)⁻/g of ash and at S/L ratio of 33 to 67 g/dm³. Higher S/L value causes an accelerating dissolution–crystallization equilibrium attainment. Cl⁻ ion acts as the inhibitor of this reaction.  相似文献   

Variable stars in the globular cluster NGC 3201 – I. Multimode SX Phe type variables     

Beata Mazur  Wojciech Krzemi&#;ski  Ian B. Thompson ^&#; 《Monthly notices of the Royal Astronomical Society》2003,340(4):1205-1213

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Multiphase magmatic activity in the Variscan Kłodzko–Złoty Stok intrusion,Polish Sudetes: evidence from SHRIMP U–Pb zircon ages     

Jokubauskas  Petras  Bagiński  Bogusław  Macdonald  Ray  Krzemińska  Ewa 《International Journal of Earth Sciences》2018,107(5):1623-1639

International Journal of Earth Sciences - The Kłodzko–Złoty Stok intrusion (KZSI), located in the NE part of the Bohemian Massif of Central Europe, has preserved records of the...  相似文献   

Plan‐form evolution of ancient meandering rivers reconstructed from longitudinal outcrop sections     

Massimiliano Ghinassi  Wojciech Nemec  Mauro Aldinucci  Slavomir Nehyba  Volkan Özaksoy  Francesco Fidolini 《Sedimentology》2014,61(4):952-977

The mode of channel‐bend transformation (i.e. expansion, translation, rotation or a combination thereof) has a direct bearing on the dimensions, shape, bedding architecture and connectivity of point‐bar sandstone bodies within a fluvial meander belt, but is generally difficult to recognize in vertical outcrops. This study demonstrates how the bend transformation mode and relative rate of channel‐floor aggradation can be deciphered from longitudinal outcrop sections aligned parallel to the meander‐belt axis, as a crucial methodological aid to the reconstruction of ancient fluvial systems and the development of outcrop analogue models for fluvial petroleum reservoirs. The study focuses on single‐storey and multi‐storey fluvial meander‐belt sandstone bodies in the Palaeogene piggyback Boyabat Basin of north‐central Turkey. The sandstone bodies are several hundred metres wide, 5 to 40 m thick and encased in muddy floodplain deposits. The individual channel‐belt storeys are 5 to 9 m thick and their transverse sections show lateral‐accretion bed packages representing point bars. Point bars in longitudinal sections are recognizable as broad mounds whose parts with downstream‐inclined, subhorizontal and upstream‐inclined bedding represent, respectively, the bar downstream, central and upstream parts. The inter‐bar channel thalweg is recognizable as the transition zone between adjacent point‐bar bedsets with opposing dip directions into or out of the outcrop section. The diverging or converging adjacent thalweg trajectories, or a trajectory migrating in up‐valley direction, indicate point‐bar broadening and hence channel‐bend expansion. A concurrent down‐valley migration of adjacent trajectories indicates channel‐bend translation. Bend rotation is recognizable from the replacement of a depositional riffle by an erosional pool zone or vice versa along the thalweg trajectory. The steepness of the thalweg trajectory reflects the relative rate of channel‐floor aggradation. This study discusses further how the late‐stage foreland tectonics, with its alternating pulses of uplift and subsidence and a progressive narrowing of the basin, has forced aggradation of fluvial channels and caused vertical stacking of meander belts.  相似文献   

Gully erosion as a natural hazard: the educational role of geotourism     

Zg&#;obicki  Wojciech  Ko&#;ody&#;ska-Gawrysiak  Renata  Gawrysiak  Leszek 《Natural Hazards》2014,70(1):159-172

Gully erosion is one of the greatest natural hazards in the loess areas of E. (Eastern) Poland. At the same time, permanent gullies are a major tourist attraction and can provide a basis for the development of geotourism. The study objective was to assess the possibilities of using the loess gullies for educational purposes. Detailed studies were conducted within the municipality of Kazimierz Dolny, an area with an extremely high concentration of permanent gullies. The questionnaire survey of students and tourists (nearly 300 surveys were completed) showed that the respondents’ knowledge of geomorphology was limited, despite their familiarity with gullies. In most cases, they were unable to accurately identify the determinants of gully erosion, its negative effects and methods for preventing it. An assessment of the tourism and geotourism potential of the municipality made it possible to identify the sites (gullies) that can perform an educational function, with regard to gully erosion. The establishment of the Małopolska Vistula Gap Geopark, whose highlights will include numerous loess gullies, can pave the way for the development of geotourism.

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An Iterative Method for Calculation of Wind Profiles at the Mesoscale and Microscale     

Adamiec-Wójcik  Iwona  Brzozowska  Lucyna  Drąg  Łukasz  Wojciech  Stanisław 《Boundary-Layer Meteorology》2022,184(3):423-440

Boundary-Layer Meteorology - Space–time correlations are fundamental to statistical theories and turbulence modelling. However, experimental studies of space–time correlations are often...  相似文献   

Searching for evidence of hydrothermal activity at Apollinaris Mons,Mars     

M. Ramy El Maarry  James M. Dohm  Giuseppe A. Marzo  Robin Fergason  Walter Goetz  Essam Heggy  Andreas Pack  Wojciech J. Markiewicz 《Icarus》2012,217(1):297-314

A multidisciplinary approach involving various remote sensing instruments is used to investigate Apollinaris Mons, a prominent volcano on Mars, as well as the surrounding plains for signs of prolonged hydrologic and volcanic, and possibly hydrothermal activity. The main findings include (1) evidence from laser altimetry indicating the large thickness (1.5–2 km at some locations) of the fan deposits draping the southern flank contrary to previous estimates, coupled with possible layering which point to a significant emplacement phase at Apollinaris Mons, (2) corroboration of Robinson et al. (Robinson, M.S., Mouginis-Mark, P.J., Zimbelman, J.R., Wu, S.S.C., Ablin, K.K., Howington-Kraus, A.E. [1993]. Icarus 104, 301–323) hypothesis regarding the formation of incised valleys on the western flanks by density current erosion which would indicate magma–water interaction or, alternatively, volatile-rich magmas early in the volcano’s history, (3) mounds of diverse geometric shapes, many of which display summit depressions and occur among faults and fractures, possibly marking venting, (4) strong indicators on the flanks of the volcano for lahar events, and possibly, a caldera lake, (5) ubiquitous presence of impact craters displaying fluidized ejecta in both shield-forming (flank and caldera) materials and materials that surround the volcano that are indicative of water-rich target materials at the time of impact, (6) long-term complex association in time among shield-forming materials and Medusae Fossae Formation.The findings point to a site of extensive volcanic and hydrologic activity with possibly a period of magma–water interaction and hydrothermal activity. Finally, we propose that the mound structures around Apollinaris should be prime targets for further in situ exploration and search for possible exobiological signatures.  相似文献   

Morphology of the cloud tops as observed by the Venus Express Monitoring Camera     

Dmitrij V. Titov  Wojciech J. Markiewicz  Nikolay I. Ignatiev  Li Song  Sanjay S. Limaye  Agustin Sanchez-Lavega  Jonas Hesemann  Miguel Almeida  Thomas Roatsch  Klaus-Dieter Matz  Frank Scholten  David Crisp  Larry W. Esposito  Stubbe F. Hviid  Ralf Jaumann  Horst U. Keller  Richard Moissl 《Icarus》2012,217(2):682-701

Since the discovery of ultraviolet markings on Venus, their observations have been a powerful tool to study the morphology, motions and dynamical state at the cloud top level. Here we present the results of investigation of the cloud top morphology performed by the Venus Monitoring Camera (VMC) during more than 3 years of the Venus Express mission. The camera acquires images in four narrow-band filters centered at 365, 513, 965 and 1010 nm with spatial resolution from 50 km at apocentre to a few hundred of meters at pericentre. The VMC experiment provides a significant improvement in the Venus imaging as compared to the capabilities of the earlier missions. The camera discovered new cloud features like bright “lace clouds” and cloud columns at the low latitudes, dark polar oval and narrow circular and spiral “grooves” in the polar regions, different types of waves at the high latitudes. The VMC observations revealed detailed structure of the sub-solar region and the afternoon convective wake, the bow-shape features and convective cells, the mid-latitude transition region and the “polar cap”. The polar orbit of the satellite enables for the first time nadir viewing of the Southern polar regions and an opportunity to zoom in on the planet. The experiment returned numerous images of the Venus limb and documented global and local brightening events. VMC provided almost continuous monitoring of the planet with high temporal resolution that allowed one to follow changes in the cloud morphology at various scales.We present the in-flight performance of the instrument and focus in particular on the data from the ultraviolet channel, centered at the characteristic wavelength of the unknown UV absorber that yields the highest contrasts on the cloud top. Low latitudes are dominated by relatively dark clouds that have mottled and fragmented appearance clearly indicating convective activity in the sub-solar region. At ～50° latitude this pattern gives way to streaky clouds suggesting that horizontal, almost laminar, flow prevails here. Poleward from about 60°S the planet is covered by almost featureless bright polar hood sometimes crossed by dark narrow (～300 km) spiral or circular structures. This global cloud pattern can change on time scales of a few days resulting in global and local “brightening events” when the bright haze can extend far into low latitudes and/or increase its brightness by 30%. Close-up snapshots reveal plenty of morphological details like convective cells, cloud streaks, cumulus-like columns, wave trains. Different kinds of small scale waves are frequently observed at the cloud top. The wave activity is mainly observed in the 65–80° latitude band and is in particular concentrated in the region of Ishtar Terra that suggests their possible orographic origin. The VMC observations have important implications for the problems of the unknown UV absorber, microphysical processes, dynamics and radiative energy balance at the cloud tops. They are only briefly discussed in the paper, but each of them will be the subject of a dedicated study.  相似文献   

Extending the double difference location technique—improving hypocenter depth determination     

Lukasz?RudzińskiEmail author  Wojciech?D?bski 《Journal of Seismology》2013,17(1):83-94

Locating the seismic event hypocenter is the very first issue undertaken when studying any seismological problem. Thus, the accuracy of the obtained solution can significantly influence consecutive stages of an analysis, so there is a continuous demand for new, more efficient, and accurate location algorithms. It is well recognized that there exists no single universal location algorithm which performs equally well in all situations. Seismic activity and its spatial variability over time, seismic network geometry, and the controlled area’s geological complexity are factors influencing the performance of location algorithms. For example, in the case of mining applications, the planarity of the seismic network usually operated at the exploitation level becomes an important issue limiting the accuracy of location of the hypocenter depths. In this paper, we push forward the discussion on the performance of the newly proposed location algorithm called the extended double difference (EDD), concentrating on the reliability of source depth estimation for mining-induced seismic events. We demonstrate that the EDD algorithm very efficiently uses information originating from the nonplanarity of the seismic network, improving the hypocenter depth estimates with respect to the classical double difference technique. Methodological considerations are illustrated by real data analysis of selected events from the Rudna copper mine (Poland).  相似文献   

The cryosphere and glacial permafrost as its integral component     

Wojciech Dobiński 《Central European Journal of Geosciences》2012,4(4):623-640

Since Earth sciences have undertaken studies of other celestial bodies, its various fields have moved beyond the scope of study assigned to them by name. Interest in space makes it necessary to abandon research geocentrism and reverse relations when comparing the structure of the Earth with other celestial bodies. As an exceptional place in the universe, it should not be the Earth which constitutes a reference point, especially in cryospheric research, but rather the other celestial bodies of our planetary system. This approach, referred to as ??Spatial Uniformitarianism,?? is the basis for determining the place of ice in the environment and for assigning it to the lithosphere. Ice can be penetrated by frost just as other minerals and rocks, so the occurrence of permafrost may yet be attributed to glaciers and ice-caps. In the article, the occurrence of glacial permafrost has been worked out on the basis of a thermal classification of glaciers with a thorough understanding of the phenomenon. This allows us to specify permafrost??s presence beneath glaciers and ice-caps, a concept which had been needlessly vague. Further, by considering rock glaciers as a mixture of two types of rocks, and by understanding the importance of movement in their evolution, we are now closer to fruitfully determining their role in the environment, their geomorphological significance.  相似文献