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EN
The Lower Jurassic to Aalenian carbonate-clastic Dudziniec Formation exposed in the autochthonous unit of the Tatra Mountains (Kościeliska Valley) hosts neptunian dykes filled with various deposits. The development of the fissures took place in multiple stages, with the same fractures opening several times, as is indicated by their architecture, occurrence of internal breccias and arrangement of the infilling sediments. Various types of internal deposits were derived in a different manner and from different sources. Fine carbonate sediments, represented by variously coloured pelitic limestones, calcilutites and fine calcarenites, most probably come from uplifted and corroded carbonate massifs (possibly from the allochthonous units of the High-Tatric succession). Products of weathering, both in dissolved form and as small particles, were washed into the sedimentary basin of the autochthonous unit, and redeposited within the dykes. The sandy varieties of the infillings, represented by red, ferruginous calcareous sandstones, come directly from the host rocks or from loose sediments present on the sea bottom at the time of fracturing. The most probable age of the infilling sediments is Sinemurian to Pliensbachian. The occurrence of dykes of this age is yet another feature confirming that the sedimentary development of the Lower Jurassic sandy-carbonate facies in the autochthonous unit was strongly influenced by synsedimentary tectonic activity, such as block-faulting.
EN
Modern computational chemistry offers a wide variety of methods allowing us to investigate very complex systems. In the current study, we would like to focus on ab initio and classical molecular dynamics to show their applications in our research. Car-Parrinello molecular dynamics (CPMD) was carried out to study compounds possessing intra- and intermolecular hydrogen bonds. Our simulations were performed in vacuum, in solvent and in crystalline phase. It is well known that intramolecular hydrogen bonding stabilizes 3D structure of molecules. The strength of the bonding and its features are influenced by inductive and steric effects. Our short overview on CPMD application to systems with intramolecular HB we start from Schiff and Mannich bases -model compounds to investigate intramolecular hydrogen bonding. Other examples reported here derive from the class of N-oxide type compounds. Special attention was devoted to another representative structure in such investigations – picolinic acid N-oxide. In some examples listed above proton transfer phenomena occurred making these compounds interesting objects for future excited state studies. Aliphatic boronic acid was used as a model example to study intermolecular hydrogen bonds based on CPMD method. Further, classical molecular dynamics was applied to investigate proteins. Here, we would like to report our results for two biomolecules. The first one is proteinase K for which the impact of mercury(II) on its catalytic center was studied. The second one is streptavidin. For the latter one its complexes with biotinylated ligands were investigated. We close our review with a paragraph describing further development and perspectives related to CPMD method.
EN
The purpose of this study was to assess if 65 dB and 4000 Hz stimuli affect postural stability of young normal hearing people. Methods: Posturography examinations belong to clinical tests which evaluate the motor skills. Posturography can be divided into static posturography and dynamic posturography. In both, static posturography and dynamic posturography, patient stays on the platform with opened and closed eyes, but in the case of dynamic one, platform is unstable. In this study the Multitest Equilibre platform produced by FRAMIRAL was used. Patients took part in tests with opened and closed eyes, on stable and unstable platform. Additionally patients were exposed to 65 dB and 4000 Hz acoustic stimuli. The sound pressure level, and frequency was belonging to the best audibly frequency range. Results: Parameters such as velocity and surface were examined. The difference between velocity measured with acoustic stimuli and without acoustic stimuli was observed. On the other hand there was no difference in surface results. Conclusions: The statistically significant difference between velocity of patients center of gravity movements, measured on unstable platform, in the presence of 4000 Hz, 65 dB acoustic stimulus and without additional disturbances was observed.
EN
During the Triassic/Jurassic boundary interval and in the Jurassic, the Triassic carbonate platforms occupying the northern shelf of the Western Tethys were subjected to disintegration. Record of these processes in the Alpine-Carpathian area is incomplete and contains a number of stratigraphic gaps. In the High-Tatric succession of the Tatra Mountains (Central Western Carpathians) stratigraphic gaps expressed by unconformity surfaces occur between the Triassic and the Middle Jurassic. In particular areas, the Triassic is directly overlain by the Dudziniec Formation (Sinemurian-Bajocian), the Smolegowa Formation (Bajocian), the Krupianka Formation (Bathonian) or the Raptawicka Turnia Formation (Callovian-Hauterivian). The occurrence of Bajocian and Bathonian deposits is limited to isolated lenticular bodies or to infillings of neptunian dykes penetrating the Triassic. Spatial relations between particular Jurassic lithosomes and the occurrence of stratigraphic gaps between particular units allow discerning four main unconformities. In the stratigraphical order these are: base of the Dudziniec Format ion (erosional unconformity), base of the Smolegowa Formation (penacordance or parat conformity), base of the Krupianka Format ion (erosional unconformity) and base of the Raptawicka Turnia Formation (drowning unconformity). Following episodes of erosion modified the previously developed unconformity surfaces, which resulted in complex modern architecture of the Triassic/Jurassic contact, as well as between particular Jurassic formations.
EN
Sediments of the Dudziniec Formation (Lower Jurassic – Aalenian) outcropping in the Kościeliska Valley (autochthonous unit of the High-Tatric series) are represented by a range of mixed carbonate-clastic deposits. Seven lithofacies have been distinguished based on lithology, sedimentary structures, colour and composition of intra- and extraclasts, with sandstones and crinoidal limestones as end members of a continuous spectrum of facies. The study area represents a shallower part of the sedimentary basin located in the vicinity of source areas, as compared to the Chochołowska Valley region located in the west. Facies characteristics and distribution were controlled mainly by synsedimentary tectonic activity, with sandy varieties representing periods of faulting with enhanced influx of extraclasts, and with crinoidal limestones corresponding to intervals of relative tectonic stability. Such influence of synsedimentary tectonics on the deposition in the Early Jurassic strongly resembles the Middle Jurassic development in the High-Tatric area. Neptunian dykes cutting the Dudziniec Formation, and most probably filled by Lower Jurassic sediments, are yet another indication of tectonic instability of the area in the Early Jurassic.
EN
The geometric and spectrocopic properties of 2-hydroxy-thiobenzhydrazide and 2-hydroxy-benzhydrazide were investigated within the frame work of Density Functional Theory (DFT). Special attention was devoted to the description and analysis of intra- and intermolecular hydrogen bonds. The choice of the compounds was dictated by their structural similarity and the presence of two types of hydrogen bridges: O–H...S (in 2-hydroxy-thiobenzhydrazide, less common) and O–H...O (in 2-hydroxy-benzhydrazide). The latter could be classified as a low-barrier hydrogen bond (LBHB). First the DFT method was used to obtain the geometric parameters for the monomeric and dimeric forms of the compounds at various levels of theory. Then the binding energy was calculated for the dimeric forms to estimate the strength of the intermolecular hydrogen bonds. Atoms in Molecules (AIM) theory was applied to show quantitatively how the formation of the intermolecular hydrogen bonds affects the strength of the intramolecular hydrogen bonds. The electron density and its Laplacian were calculated for the bond critical points defining the H-bridges. Car-Parrinello molecular dynamics (CPMD) was then used to investigate the changes in the geometric parameters as a function of simulation time. This part of the computational study was performed in vacuo and in the solid state. The vibrational properties of the investigated hydrazides were obtained via Fourier transform of the autocorrelation functions of the dipole moment and atomic velocity. It was found that the formation of the intermolecular H-bonds does not significantly affect the strength of the intramolecular H-bonds. There fore inductive and steric effects out side the immediate vicinity of the intramolecular bridge have minor influence on its investigated properties. The application of CPMD gave a more detailed picture of the bridged protons’ dynamics. The computational results agree with available experimental data. The influence of the intermolecular hydrogen bonding net work and non-bonded crystal field interactions on the vibrational features of the investigated molecules is demonstrated and discussed.
EN
Experimental and theoretical investigations were performed for 5-amino-3-methylisoxazole- 4-carboxylic acid N-(2,4,6-trimethylpyridinium)amide chlorate(VII) salt, which belongs to the group of isoxazole derivatives, potential antibacterial or antifungal agents. The results related to its synthesis and X-ray diffraction are presented. Quantum- chemical DFT calculations were carried out for the title molecule and its analogues. Atomic charges were calculated according to Bader's Atoms In Molecules Theory in order to find the quantum similarities of the molecules. The Polarizable Continuum Model (SCRF/PCM) with water (_ = 78.39) as a solvent was used to determine the environment effects on molecular properties. The solid-state geometry optimization with Geodecker's pseudopotentials and plane-wave basis set was used to compare experimental and calculated geometrical parameters for the title compound.
EN
Theoretical calculations on 5-amino-3-methylisoxazole-4-carboxylic acid hydrazide Schiff base derivatives using Polarizable Continuum Model in order to account for water solvation effects are presented. The compounds studied exhibit biological (immunosuppressing or immunostimulating) activity, measured experimentally in various assays. The quantum chemical DFT calculations are used to obtain electronic descriptors of molecular structure. These descriptors, together with other physicochemical parameters, are used to derive quantitative relationships between the structure and the biological activity.
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