15 research outputs found

    OCHRE PRECIPITATES AND ACID MINE DRAINAGE IN A MINE ENVIRONMENT

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    This paper is focused to characterize the ochre precipitates and the mine water effluents of some old mine adits and settling pits after mining of polymetallic ores in Slovakia. It was shown that the mine water effluents from two different types of deposits (adits; settling pits) have similar composition and represent slightly acidic sulphate water (pH in range 5.60-6.05, sulphate concentration from 1160 to 1905 g.dm-3). The ochreous precipitates were characterized by methods of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and B.E.T. method for measuring the specific surface area and porosity. The dominant phases were ferrihydrite with goethite or goethite with lepidocrocide

    It’s Complicated: On Problematic Relationships Between Primary School Teachers and Parents

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    Tento text prezentuje výsledky kvalitativního šetření, které proběhlo mezi učiteli prvního stupně ZŠ a matkami jejich žáků. Zkoumán je vztah rodiče a učitele, který je učiteli vnímaný jako problémový. Na základě výpovědí respondentů jsou popsány podoby takového vztahu (charakteristicky jsou rodiče rozděleni na pasivní a aktivní-nespokojené, přičemž projevy této nespokojenosti mohou být vůči škole hlasité, anebo tiché), a jsou zde identifikovány obtíže, které mohou z takovéhoto vztahu pro učitele či školu plynout, čímž je určité nepohodlí učitele, ale také hrozba odchodu žáka na jinou školu.This paper presents the results of qualitative research examining problematic relationships between primary school teachers and the mothers of their pupils. Based on the answers of our respondents, the paper describes the different forms of such relationships and divides parents into either passive or actively disappointed, with disappointment voiced or remaining silent. The paper also identifies challenges that accompany such relationships, such as a certain level of discomfort for teachers and the possibility of pupil transfer to another school, which need to be faced by the teachers and their schools

    Stratigraphic and tectonic control of deep-water scarp accumulation in Paleogene synorogenic basins: a case study of the Súľov Conglomerates (Middle Váh Valley, Western Carpathians)

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    The Súľov Conglomerates represent mass-transport deposits of the Súľov-Domaniža Basin. Their lithosomes are intercalated by claystones of late Thanetian (Zones P3 - P4), early Ypresian (Zones P5 - E2) and late Ypresian to early Lutetian (Zones E5 - E9) age. Claystone interbeds contain rich planktonic and agglutinated microfauna, implying deep-water environments of gravity-flow deposition. The basin was supplied by continental margin deposystems, and filled with submarine landslides, fault-scarp breccias, base-of-slope aprons, debris-flow lobes and distal fans of debrite and turbidite deposits. Synsedimentary tectonics of the Súľov-Domaniža Basin started in the late Thanetian - early Ypresian by normal faulting and disintegration of the orogenic wedge margin. Fault-related fissures were filled by carbonate bedrock breccias and banded crystalline calcite veins (onyxites). The subsidence accelerated during the Ypresian and early Lutetian by gravitational collapse and subcrustal tectonic erosion of the CWC plate. The basin subsided to lower bathyal up to abyssal depth along with downslope accumulation of mass-flow deposits. Tectonic inversion of the basin resulted from the Oligocene - early Miocene transpression (σ1 rotated from NW-SE to NNW-SSE), which changed to a transpressional regime during the Middle Miocene (σ1 rotated from NNE-SSW to NE-SW). Late Miocene tectonics were dominated by an extensional regime with σ3 axis in NNW-SSE orientation

    Crystal-Chemical and Spectroscopic Study of Gem Sphalerite from Banská Štiavnica, Slovakia

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    A complex crystal-chemical investigation based on spectroscopic methods, Electron MicroProbe Analysis (EMPA), and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) was made on sphalerite samples from the Terézia and Rozália veins in the Banská Štiavnica ore district. The yellow (sample A) and olive-green sphalerite (C) are in association only with quartz; orange sphalerite (B) is associated with quartz and chalcopyrite; and black sphalerite (D) is associated with galena, chalcopyrite, quartz, and baryte. EMPA revealed that Cd and Fe are substituting for Zn with variable proportions; the Cd/Fe ratio decreases from 2.82–2.85 in the A sample to 0.42 in the D sample. LA-ICP-MS showed that, except Cd and Fe, only Mn has content above 20; Co and Cu vary between 2 and 17 ppm. The optical absorption spectra exhibit absorption between 644 and 740 nm with three smaller humps at 669–671, 698–702, and 732–743 nm, and weaker absorption bands at 858–894 nm in the NIR region, which can be all assigned to crystal-field transitions of Fe2+. The absorption edge starts at about 600 nm to the UV region. Minimal absorption is in the yellow-red part of the visible spectrum giving rise to yellowish-orange and orange-red colors. Absorption in the red region for olive-green sphalerite is more pronounced, explaining the shift to greenish hues. In black sphalerite, the absorption pattern is similar to the olive-green sphalerite, but the bands in the 644 to 740 nm region are less defined. The black color could be caused by slightly higher concentrations of Fe, the smaller size of individual crystals in the aggregate reducing macroscopic transparency, and/or the presence of submicroscopic inclusions
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