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<p>In the winter of 2017 three undisturbed sediment cores were retrieved from the Szemes Basin of Lake Balaton. The sediments were sampled for AMS <sup>14</sup>C dating and we used 8 of the radiocarbon dates for age-depth modelling. Based on this, the investigated sediment sequence covers the entire Holocene and Late Glacial period and the bottom of the sediment is ca. ~16,000 cal yr BP old. X-ray fluorescence spectrometry (XRF) was used to reconstruct rapid changes in the element content of the lake sediment. The evaluation of the measured results makes it possible to reconstruct the changes in the discharge environment and lake water level that can be related to the climate and human impact. Based on the data, two major evaporation events can be observed at 5500 BP and 8100 BP. These results were also verified by oxygen isotope studies. To reconstruct the energy of the deposition environment, particle size analysis was performed. The obtained results confirmed that river sediments are common at the bottom of Lake Balaton sediments, while biogenic carbonate dominates in the upper, Holocene part of the sediment core. To identify each mineral phase in the sediment, X-ray diffraction (XRD) studies were used to determine the ratio of calcite to Mg-calcite. Based on our XRF measurements, focusing primarily on quantitative changes in magnesium and calcium, transmission electron microscopy (TEM) studies were performed, mainly in the Mg enrichment layer around 8100 BP. The precipitation of biogenic carbonate in Lake Balaton is still taking place, mainly in the form of calcite and Mg-calcite. Their relative proportions strongly depend on the Mg saturation of the water and the substrates on which they are separated. From our results we can draw conclusions about the possible previous deeper phases of the lake and the evaporation conditions of the water. The data obtained from transmission electron microscopy shows a good agreement with the results of the XRF measurement, the proportion of Mg-calcite increases around 8100 BP that likely indicate drier climatic conditions connectable to the well know 8.2 ka cal BP climatic reversal.</p>

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Interfacial intermetallic compounds (IMC) play an important role in Sn-Cu lead-free soldering. The size and morphology of the intermetallic compounds formed between the lead-free solder and the Cu substrate have a significant effect on the mechanical strength of the solder joint.In the soldering process of Sn-Cu alloys, Cu 6 Sn 5 intermetallic compounds are formed. The complex structural behaviour of Cu 6 Sn 5 IMC is temperature-and composition-dependent and it is long since subject to scientific research. The Cu 6 Sn 5 phase basically exists in two crystal structures: hexagonal η-Cu 6 Sn 5 (at temperatures above 186 • C) and monoclinic η'-Cu 6 Sn 5 (at lower temperatures). In the presence of Ni in the solder, the η-η' transformation does not occur, therefore, the η-Cu 6 Sn 5 phase remains stable.In this study the role of Ni in the (Cu,Ni) 6 Sn 5 intermetallic compound in Sn-Cu lead-free solders was examined. Sn-Cu alloys with different Cu content (0.5 to 1 mass%) were modified through Ni addition. The morphology of the intermetallic compounds of the modified Sn-Cu alloys was investigated by optical microscopy (OM) and scanning electron microscopy (SEM), the IMC phases were examined with X-ray diffraction method (XRD).

ABSTRACT. In one of the passages in the Great Cave of Șălitrari Mountain the floor is completely covered by an alluvial deposit at least 6 m in thickness, ranging from boulders, and cobbles, to sand and clay, topped by a layer of dry bat guano. Sediment and mineral samples collected from six profiles underwent broad analyses to determine their petrological and mineralogical makeup, grain-size distribution, and paleoclimatic significance. The complicated facies alternation suggests frequent changes in the former stream's hydrological parameters, with frequent flooding, leading to the hypothesis that the climate was somewhat wetter than today. Both the mineralogical composition of the sediment (ranging from quartz, mica, gypsum, phosphates, and calcite to garnet, zircon, titanite, olivine, serpentine, tourmaline, sphalerite, pyrite/chalcopyrite, and feldspars) and the petrological composition of the larger clasts (limestone, sandstone, mudstone, granitoids, serpentinite, amphibolite, diorite, gneiss, quartzite, microconglomerate, and schist) ascribe the potential source rocks to an area with contrasting lithologies, such as amphibolites, felsic and basic metaigneous, and metasedimentary rocks, mixed with a variety of detritic rocks. These rock types are not entirely comprised by the catchment area of the modern Presacina Brook, thus implying that due either to hydrological conditions, or to changes in the base level caused by river down cutting or active tectonics, the former source area was much more extensive. Based on morphological and sedimentological criteria, the cave started under pipe-full flow conditions, and further evolved during a prolonged and complex vadose phase. Evidence to support the existence of hypogene conditions is also present. Once the underground stream left the cave and most of the sediment was removed, speleothem precipitation was initiated. In this contribution we put forward evidence that argue for an extra-basinal origin of some of the alluvial sediments, an uncommon fact documented in few cave environments so far.

Further mosaic-like data were recorded on the mineral occurrences of the Carpathian–Pannonian region in this fifth member of the series arranged by countries and localities. Each “mosaic” contains a concise mineral description, mainly based on XRPD, SEM-EDX and EPMA measurements and a concise description of the mineral paragenesis. Some minerals are first-time descriptions from the entire discussed region, but all are newly documented occurrences for at least the described locality. From Hungary humboldtine and weddellite are described from the coalbed of Csordakút (Bicske), and data from Sr-rich and other Aluminium Phosphate Sulphate (APS) minerals from the ore mineralization of the Lahóca Hill at Recsk are also reported. Chemical data of Mg-rich tourmaline from the Harghita volcanic ridge are given, and also kyrgyzstanite is described from the ore mineralization of Baia Sprie, Romania. From Slovakia Na-containing sulphates (kröhnkite, ferrinatrite, tamarugite) from the ore mineralization of Farbište (Poniky) and an arsenate (bariopharmacosiderite) from the ore mineralization of Rožňava are also introduced.

The present study is a review of publications regarding special aspects of the mineralogy of the Kaba meteorite, clay minerals, hydrous phases, and organic matter. In Section 1, the history of fall and finding of the meteorite and the first classical mineralogical description in the Year 1961 are mentioned. The most frequent alteration product of primary silicates and the glassy matrix is Fe-bearing saponite. By modelling of hydrothermal alteration of Allende-type meteorites, artificial saponite could be produced. The thermodynamic study proved the possibility of hydrous neoformation of silicates and magnetite at low temperatures, mostly below 100°C. The formation of Fe-rich external rims in forsterite grains by hydrothermal action was demonstrated by electron probe microanalysis and scanning electron microscopy-cathodo-luminescence methods. Foliation in CV3 carbonaceous chondrites indicates that the Kaba meteorite is derived from the external, shallow zone of the parent body. A combination of X-ray power diffraction (XRD) and Mössbauer spectroscopy made the exact modal analysis of CV3 chondrites possible, including Kaba. The study of alteration by in situ determination of stable oxygen isotope contents may provide constraints regarding the oxygen isotopic composition of the aqueous fluid on the CV parent asteroid. The degree of thermal metamorphism of the organic matter was determined by using Raman spectroscopy. The presence of aromatic and aliphatic, saturated and unsaturated hydrocarbons, and various amino acids was demonstrated. The non-biogenic origin is more probable; however, there are textural and mineralogical observations that may indicate also the biogenic origin of organic matter. In addition to the review of the literature above, as an appendix, shortly new XRD investigations of the authors are reported that indicated smectite-like phases in a thin section made of the meteorite.