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201.
Mateusz Barczewski Danuta Chmielewska Monika Dobrzyńska-Mizera Beata Dudziec Tomasz Sterzyński 《International Journal of Polymer Analysis and Characterization》2014,19(6):500-509
This article presents a study of the thermal stability of polypropylene-based nanocomposites filled with tetrasilanolphenyl silsesquioxane (phPOSS). Nanofillers were introduced into a polypropylene matrix in three different amounts: 2, 5, and 10 wt.%. Investigations were carried out by means of thermogravimetric analyses conducted in inert and oxidizing atmospheres, Fourier transform-infrared spectroscopy, scanning electron microscopy, and flammability UL-94 test. The addition of phPOSS into the polymeric matrix increased thermal stability in comparison to neat iPP and introduced significant changes in the flammability of iPP/phPOSS nanocomposites. 相似文献
202.
Mateusz Tykierko 《Physica D: Nonlinear Phenomena》2008,237(1):6-13
Change detection is the crucial subject in dynamical systems. There are suitable methods for detecting changes for linear systems and some methods for nonlinear systems, but there is a lack of methods concerning chaotic systems. This paper presents change detection techniques for dynamical systems with chaos. We consider the dynamical system described by the time series which originated from ordinary differential equation and real-world phenomena. We assume that the change parameters are unknown and the change could be either slight or drastic. The process of change detection is based on characteristic dynamical system invariants. Changes in the invariants’ values of the dynamical systems are the indicators of change. We propose a method of change detection based on the fractal dimension and recurrence plot. The automatic detection is provided by control charts. Methods were checked by using small data sets and stream data. 相似文献
203.
Mateusz
mietana Pawe Niedziakowski Wioleta Biaobrzeska Dariusz Burnat Petr Sezemsky Marcin Koba Vitezslav Stranak Katarzyna Siuzdak Tadeusz Ossowski Robert Bogdanowicz 《Electroanalysis》2019,31(2):398-404
In this work an optical fiber sensor, where a lossy‐mode resonance (LMR) effect was obtained due to indium tin oxide (ITO) thin overlay, has been simultaneously applied as a working electrode in a 3‐electrode cyclic voltammetry electrochemical setup. Since LMR conditions highly depend on refractive index of a surrounding medium, an LMR‐based sensor was applied for optical investigations of electrolyte's properties at the ITO surface. We have found that the optical response of the sensor highly depends on the applied potential and its changes, as well as the properties of the investigated electrolyte, i. e., its composition and presence of a redox probe. Both optical and electrochemical response of the ITO‐LMR sensor to various concentrations of phosphate‐buffered saline (PBS), NaCl and Na2SO4, as well as scan rate were investigated and discussed. We have found that the responses in optical and electrical domains differ significantly and may deliver supplementary information about the investigated analyte. 相似文献
204.
This article the first reports on a fabrication and application of an electrochemical three electrode micro‐set containing: in situ plated lead film on carbon fiber working microelectrode, Ag/AgCl reference electrode and a platinum wire counter electrode placed in one casing for simultaneous Ni(II) and Co(II) traces determination by square wave adsorptive stripping voltammetry (SW AdSV). Ni(II) and Co(II) in forms of their complexes with nioxime were accumulated on the lead film plated on a carbon fibers microelectrode during standard procedure of measurement. Thanks to the fact that measurements were performed in micro‐vessel of a volume of 200 μl small amounts of reagents were used to prepare samples for measurements. In addition, because of the use of microelectrode, sample solutions were not mixed during accumulation step of measurements. This fact creates the possibility of conducting fields analysis. The experimental parameters (composition of the supporting electrolyte, potential and time of accumulation) and possible interference effects were investigated. The linear calibration graphs for Ni(II) and Co(II) were in the range from 2×10?9 to 1×10?7 mol L?1 and from 2×10?10 to 1×10?8 mol L?1 for Ni(II) and Co(II), respectively. The correctness of the proposed method was checked by determining Ni(II) and Co(II) in the certified reference material (SPS‐SW1) with satisfactory results. 相似文献
205.
Magdalena Żurowska Marek Filipowicz Michał Czerwiński Mateusz Szala 《Liquid crystals》2019,46(2):299-308
A homologous series of chiral three ring esters were synthesised and their properties were studied. The materials possess an antiferroelectric phase (SmCA*) or/and a ferroelectric phase (SmC*), which was confirmed by observations of microscopic textures using a polarising optical microscope. The phase transition temperatures and enthalpies were checked by differential scanning calorimetry. The helical pitch was measured by a spectrophotometry method. For all cases the helix is right-handed, in the antiferroelectric phase the helical pitch increases with temperature, and in the ferroelectric phase the helical pitch is short. 相似文献
206.
Rajnish Kaur Anil Kumar Mateusz Czyzycki Alessandro Migliori Andreas G. Karydas Sanjiv Puri 《X射线光谱测定》2019,48(2):126-137
In the present work, the X-ray intensity ratios, ILk/ILα (k = l, β, γ1,5, γ2,3, γ4), have been measured for different compounds of 66Dy, namely, Dy2O3, Dy2(CO3)3, Dy2(SO4)3.8H2O, DyI2, and the 66Dy metallic foil by tuning the incident photon energies across its Li (i = 1–3) absorption-edge energies covering the region 7.8–10 keV in order to investigate the influence of chemical effects on these intensity ratios in the presence of the many-body effects, which become significant at photon energies in proximity to the Li absorption-edge energies. The present measured intensity ratios ILk/ILα have been compared with two sets of values calculated using the nonrelativistic Hartree–Fock–Slater model-based Li (i = 1–3) subshell photoionization cross sections, the Dirac–Fock model-based X-ray emission rates, and two sets of the fluorescence and Coster–Kronig yields. The L3 absorption-edge energy of 66Dy in its different compounds and metallic foil has been deduced from the XANES spectra recorded in the present work. The L3 absorption-edge energy shifts obtained from these absorption-edge energies are found to increase linearly with the partial charge on the metal atom (66Dy). 相似文献
207.
Selective Alkane Oxidation by Manganese Oxide: Site Isolation of MnOx Chains at the Surface of MnWO4 Nanorods
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Xuan Li Dr. Thomas Lunkenbein Verena Pfeifer Mateusz Jastak Pia Kjaer Nielsen Dr. Frank Girgsdies Dr. Axel Knop‐Gericke Dr. Frank Rosowski Prof. Dr. Robert Schlögl Dr. Annette Trunschke 《Angewandte Chemie (International ed. in English)》2016,55(12):4092-4096
The electronic and structural properties of vanadium‐containing phases govern the formation of isolated active sites at the surface of these catalysts for selective alkane oxidation. This concept is not restricted to vanadium oxide. The deliberate use of hydrothermal techniques can turn the typical combustion catalyst manganese oxide into a selective catalyst for oxidative propane dehydrogenation. Nanostructured, crystalline MnWO4 serves as the support that stabilizes a defect‐rich MnOx surface phase. Oxygen defects can be reversibly replenished and depleted at the reaction temperature. Terminating MnOx zigzag chains on the (010) crystal planes are suspected to bear structurally site‐isolated oxygen defects that account for the unexpectedly good performance of the catalyst in propane activation. 相似文献
208.
Nieszporek K Szabelski P Drach M 《Langmuir : the ACS journal of surfaces and colloids》2005,21(16):7335-7341
The integral equation (IE) approach coupled with a quasi-Gaussian adsorption energy distribution is used to model the adsorption of single gases and their binary mixture on a heterogeneous solid surface. The adsorbing surface is assumed to be characterized by two, generally different in width, quasi-Gaussian distribution functions, each of them related to a single component of the mixture. The influence of correlations between the distribution functions associated with different components on the corresponding adsorption isotherms and phase diagrams is discussed. In particular, it is demonstrated that a lack of microscopic correlations between the adsorption energies of the components may lead to the formation of an azeotropic mixture. The predictions of the theory are also compared with the results of the grand canonical Monte Carlo (GCMC) simulations carried out for the system studied. 相似文献
209.
One of the major challenges in the computational prediction of protein–peptide complexes is the scoring of predicted models. Usually, it is very difficult to find the most accurate solutions out of the vast number of sometimes very different and potentially plausible predictions. In this work, we tested the protocol for Molecular Dynamics (MD)-based scoring of protein–peptide complex models obtained from coarse-grained (CG) docking simulations. In the first step of the scoring procedure, all models generated by CABS-dock were reconstructed starting from their original C-alpha trace representations to all-atom (AA) structures. The second step included geometry optimization of the reconstructed complexes followed by model scoring based on receptor–ligand interaction energy estimated from short MD simulations in explicit water. We used two well-known AA MD force fields, CHARMM and AMBER, and a CG MARTINI force field. Scoring results for 66 different protein–peptide complexes show that the proposed MD-based scoring approach can be used to identify protein–peptide models of high accuracy. The results also indicate that the scoring accuracy may be significantly affected by the quality of the reconstructed protein receptor structures. 相似文献
210.
Katarzyna Solarska-
ciuk Kinga Adach Sylwia Cyboran-Mikoajczyk Dorota Bonarska-Kujawa Agnieszka Rusak ucja Cwynar-Zajc Tomasz Machaowski Teofil Jesionowski Katarzyna Grzywacz Mateusz Fijakowski 《Molecules (Basel, Switzerland)》2021,26(5)
Silicon dioxide, in the form of nanoparticles, possesses unique physicochemical properties (size, shape, and a large surface to volume ratio). Therefore, it is one of the most promising materials used in biomedicine. In this paper, we compare the biological effects of both mesoporous silica nanoparticles extracted from Urtica dioica L. and pyrogenic material. Both SEM and TEM investigations confirmed the size range of tested nanoparticles was between 6 and 20 nanometers and their amorphous structure. The cytotoxic activity of the compounds and intracellular ROS were determined in relation to cells HMEC-1 and erythrocytes. The cytotoxic effects of SiO2 NPs were determined after exposure to different concentrations and three periods of incubation. The same effects for endothelial cells were tested under the same range of concentrations but after 2 and 24 h of exposure to erythrocytes. The cell viability was measured using spectrophotometric and fluorimetric assays, and the impact of the nanoparticles on the level of intracellular ROS. The obtained results indicated that bioSiO2 NPs, present higher toxicity than pyrogenic NPs and have a higher influence on ROS production. Mesoporous silica nanoparticles show good hemocompatibility but after a 24 h incubation of erythrocytes with silica, the increase in hemolysis process, the decrease in osmotic resistance of red blood cells, and shape of erythrocytes changed were observed. 相似文献