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Erythrocyte destruction during turbulent mixing
No full textabstractEN: Destruction of erythrocyte cells in a high shear environment has been investigated during turbulent conditions. It has been observed that shear stress generated in viscous sub-range of turbulence is capable of destroying erythrocytes, although viscous sub-range has been so far considered generally safe for cells. The multifractal theory of turbulence has been proposed to explain erythrocyte cells destruction in this case. Two hypotheses of cell rupture, both based on a critical stress concept, were tested and kinetic constants for multifractal model as well as for Kolmogorov theory have been calculated.score: 35collation: 147-15
Studies on the anti-hepatitis C virus activity of newly synthesized tropolone derivatives: Identification of NS3 helicase inhibitors that specifically inhibit subgenomic HCV replication
No full textabstractEN: We synthesized new tropolone derivatives substituted with cyclic amines: piperidine, piperazine or pyrrolidine. The most active anti-helicase compound (IC50 = 3.4 μM), 3,5,7-tri[(4′-methylpiperazin-1′-yl)methyl]tropolone (2), inhibited RNA replication by 50\% at 46.9 μM (EC50) and exhibited the lowest cytotoxicity (CC50) \>1 mM resulting in a selectivity index (SI = CC50/EC50) \>21. The most efficient replication inhibitor, 3,5,7-tri[(4′-methylpiperidin-1′-yl)methyl]tropolone (6), inhibited RNA replication with an EC50 of 32.0 μM and a SI value of 17.4, whereas 3,5,7-tri[(3′-methylpiperidin-1′-yl)methyl]tropolone (7) exhibited a slightly lower activity with an EC50 of 35.6 μM and a SI of 9.8.score: 30collation: 5129-513
Some hydrodynamic aspects of precipitation
No full textabstractEN: Precipitation of sparingly soluble materials from two aqueous ionic solutions is considered. It is well known that the flow conditions in the system can affect particle size distribution and particle morphology. In the paper, three problems related to interactions between hydrodynamics (turbulent flow) and the precipitation process are considered, namely, effects of mixing on crystal size using computational fluid dynamics (CFD), relation between turbulent diffusion of fluids and solid particles, and the problem of aggregation kernel for small particles.score: 35collation: 9-1
Multi-elemental analysis of non-food packaging materials by inductively coupled plasma-time of flight-mass spectrometry
No full textabstractEN: Commercial non-food packaging materials of four different matrices (paper, low density polyethylene (LDPE), polyethylene-polypropylene (PE-PP) and high density polyethylene (HDPE)) were examined for the content of Cr, Ni, Cu, Zn, As, Mo, Cd, Sb, Ba, Hg, Tl, Pb and U. The examined samples (0.17–0.35 g) were digested in HNO3 and H2O2 (papers, LDPE and PE-PP) and in HNO3, H2SO4 and H2O2 (HDPE) using microwave assisted high pressure system. The inductively coupled plasma-time of flight-mass spectrometry (ICP-TOFMS) has been employed as the detection technique. All measurements were carried out using internal standardization. Yttrium and rhodium (50 ng g−1) were used as internal standards. The detection and quantification limits obtained were in the range of 0.005 ng g−1 (52Cr) to 0.51 ng g−1 (66Zn) and 0.015 μg g−1 (52Cr) to 2.02 μg g−1 (66Zn) of dry mass, respectively. The evaluated contents (mg kg−1) of particular elements in the examined materials were as follows: 0.22–219; \<1.05–9.03; 1.25–112; \<2.02–449; \<0.98–\<1.30; \<0.36–2.06; \<0.29–113; \<0.22–44.1; \<0.06–57.4; \<0.66–\<0.88; \<0.08–0.24; \<0.13–1222 and \<0.08–0.44 for Cr, Ni, Cu, Zn, As, Mo, Cd, Sb, Ba, Hg, Tl, Pb and U, respectively.score: 40collation: 937-94
Determination of ruthenium and osmium in each other's presence in chloride solutions by direct and third-order derivative spectrophotometry
No full textabstractEN: Ruthenium and osmium (up to 20 μg Ru(Os) ml−1) can be determined in chloride solutions directly after absorption of RuO4 and OsO4 in hydrochloric acid. In 9 M HCl, RuO4 and OsO4 are quantitatively converted into RuCl62− (λmax = 480.0 nm, ε = 4.8 × 103 l mol−1 cm−1) and OsCl62− (λmax = 334.8 nm, ε = 8.4 × 103 l mol−1 cm−1) respectively. Osmium does not interfere with the determination of ruthenium in the form of the RuCl62− complex by direct spectrophotometry. The absorbance of the obtained solution at λmax = 480.0 nm corresponds only to the concentration of ruthenium. A derivative spectrophotometric method using numerical calculation of absorption spectra of the RuCl62− and OsCl62− complexes has been developed for the determination of osmium in a mixture with ruthenium. The interfering effect of ruthenium on the determination of osmium can be eliminated by measuring the value of a third-order derivative spectrum of the OsCl62− complex at 350.0 nm (“zero-crossing point” of ruthenium). Simple and rapid determination of ruthenium and osmium in a calibration standard solution of the noble metals (Ru, Rh, Pd, Os, Ir, Pt and Au) for plasma spectroscopy using the proposed methods has been achieved.score: 40collation: 471-47
Archiving shape and appearance of cultural heritage objects using structured light projection and multispectral imaging
No full textabstractEN: Abstract. To create faithful reproduction of a cultural heritage object, it is crucial to gather information on intrinsic optical properties of the object’s surface, as well as its geometry. An integrated device has been developed that performs a three-dimensional measurement using structured light projection, followed by multispectral imaging for precise color retrieval and directional illumination for estimating bidirectional reflectance distribution function (BRDF) parameters. The main advantage shown in this work is the use of only one detector during the whole acquisition process to assure ideal correspondence of multimodal surface data in the image space. A method is shown for performing the measurement using an integrated device. Methods of data organization and processing are described facilitating robust operation of the developed software. A prototype setup for the integrated system is presented together with measurement parameters and sample measurement.score: 20collation: 021115-
Optimized point cloud triangulation for 3D scanning systems
No full textabstractEN: This article deals with a new Mesh3D algorithm used for triangulation of point clouds obtained from real 3D objects via optical scanning systems. The algorithm is characterized by a high level of automation. Triangle meshes obtained by using this algorithm are of a better quality than those created through the application of popular algorithms. Procedures used for areas with large shape gradients allow us to obtain a higher accuracy of a geometric object representation. It is also a very efficient method even when the procedure of point clouds smoothing is applied initially. The implementation of this kind of a complex mesh quality assessment system enables us to improve the smoothness and continuity of the mesh, which allows us to obtain more realistic and visually better reconstructions of objects.score: 7collation: 349-37
Dissolved Ozone Flotation as a innovative and prospect method for treatment of micropollutants and wastewater treatment costs reduction
No full textabstractEN: The lack of fresh water is one of the major threats for people. The extremely sufficient and cost saving methods for water and wastewater treatment must be applied. The paper shows possibility of using traditional Dissolved Air Flotation method (DAF) with alternation of feeding gas by ozone (Dissolved Ozone Flotation - DOF) instead of air to obtain better treatment results and possibilities of decreasing the costs of water and wastewater treatment. Moreover the DOF method may come in effective in case of more and more restrictive recommendations regarding water quality and micro-pollutants removal. As the method is on early stage of the research many technical aspects and mechanisms must be taken into consideration and to be investigated. Presumably the DOF method could be applied in technical scale for pre-treatment of industrial wastewaters, fracturing fluids, water with algae or for final separation of effluent and excess sludge in municipal wastewater treatment plants.score: 3collation: 1-
Numerical-symbolic large-signal simulation of switched circuits
No full textabstractEN: Switched circuits have often switching devices modelled as ideal switches in order to improve efficiency of time-domain simulation and provide a quick assessment of the quality of the design. Inconsistent initial conditions (IIC) may appear and conventional simulators would give incorrect results. An algorithm for analysis of circuits with IIC exploiting the mixed numerical-symbolic analysis is introduced. The method handles nonlinear circuits and detects the order of Dirac impulse appearing in the response. It makes possible accurate calculation of areas of Dirac impulses and initial conditions after switchingscore: 3collation: 620-623 vol.
Selected Problems of Non-Linear (Non-Smooth) Dynamics of Rail Vehicles in a Curved Track
No full textabstractEN: The contribution presents four problems connected with the Colloquium topics. They are of theoretical nature in the wider aspect but all refer to the results of practical simulations of rail vehicle motion in a curved track. The first two can be counted to typical non-smooth problems in rail vehicle dynamics. They refer to two-point contact modelling and vehicle stability in curves, respectively. The third problem is closely related to the second one. It refers to railway vehicle dynamics above critical velocity in transition curves. The forth one can also be recognized as the non-smooth problem but not so typical one. It refers to modelling the kinematics in a curved track. All the problems reveal that one needs to be very careful when studying rail vehicle dynamics and trying to simplify its non-linearities at the same time. Non-smooth functions can influence results of numerical analysis strongly, being the features of the physical and modelling nature.score: 3collation: 87-9