Selection of coal for small district-heating stations in Poland as a method of avoiding investments in flue-gas desulphurization

Poland is one of the biggest producers of hard coal in the world and uses its domestic coal for electricity and heat generation: 42 million tons for electricity and heat production in power industry, and about 8–10 million tons used by small district-heating stations annually. Changes in demand for coal, destined for heat generation, result from the changes in the forecast structure of energy carriers to be used by local heating stations and the new emission standards coming, this year, into effect in Poland. To meet the regulations, the heat generators have to keep to environmental requirements. The cheapest solution is to burn the compliance coal. The comparison of the forecasts for coal demand and supply and the possibility of adjusting quantitative and qualitative requirements of the smaller coal consumers points out that it would be possible, when the market rules, to heal the situation between coal producers and coal consumers in Poland.     

Interactions among Lacosamide and Second-Generation Antiepileptic Drugs in the Tonic-Clonic Seizure Model in Mice

Combination therapy with two or three antiseizure medications (ASMs) is sometimes a preferred method of treatment in epilepsy patients. (1) Background: To detect the most beneficial combination among three ASMs, a screen test evaluating in vivo interactions with respect to their anticonvulsant properties, was conducted on albino Swiss mice; (2) Methods: Classification of interactions among lacosamide (LCM) and selected second-generation ASMs (lamotrigine (LTG), pregabalin (PGB), oxcarbazepine (OXC), and topiramate (TPM)) was based on the isobolographic analysis in the mouse maximal electroshock-induced seizure (MES) model. Interactions among LCM and second-generation ASMs were visualized using a polygonogram; (3) Results: In the mouse MES model, synergy was observed for the combinations of LCM + TPM + PGB and LCM + OXC + PGB. Additivity was reported for the other combinations tested i.e., LCM + LTG + TPM, LCM + LTG + PGB, LCM + LTG + OXC, and LCM + OXC + TPM in this seizure model. No adverse effects associated with triple ASM combinations, containing LCM and second-generation ASMs were observed in mice; (4) Conclusions: The combination of LCM + TPM + PGB was the most beneficial combination among the tested in this study, offering synergistic suppression of tonic-clonic seizures in mice subjected to the MES model. Both the isobolographic analysis and polygonogram method can be recommended for experimental epileptology when classifying interactions among the ASMs.     

Optimal temperature profiles for parallel-consecutive reactions with deactivating catalyst

A cocurrent tubular reactor with temperature profile control and recycle of moving deactivating catalyst has been investigated. For the temperature-dependent catalyst deactivation, the optimization problem has been formulated in which a maximum of a profit flux is achieved by the best choice of temperature profile and residence time of reactants for the set of catalytic reactions A+B→R and R+B→S with desired product R, the rates of reactions have been described separately for every reagent by the expressions containing (temperature dependent) reaction rate constants, concentrations of reagents, catalyst activity, as well as catalyst concentration in the reacting suspension and a measure of the slip between reagents and solid catalyst particles. The algorithms of maximum principle have been used for optimization. The optimal solutions show that a shape of the optimal temperature profile depends on the mutual relations between activation energies of reactions and catalyst deactivation. It has been proved that the optimal temperature profile is a result of the compromise between the overall production rate of desired reagent R (production rate in the first reaction minus disappearance rate in the second one), necessity of saving of reagents residence time (reactor volume) and necessity of saving catalyst; the most important influence on the optimal temperature profile is associated with necessity of saving the catalyst. When catalyst recycle ratio increases (mean number of catalyst particles residing in reactor increases), optimal temperatures save the catalyst, as the optimal profile is shifted in direction of lower temperatures. The same is observed when catalyst slip increases (catalyst residence time in reactor increases). Despite of variation in the catalyst concentration the optimal profile is practically the same because the decay rate is affected only by instantaneous activity of catalyst. When reactor unit volume price decreases, catalyst residence time increases, whereas optimal temperature profile is shifted to lower temperatures. When economic value of unit activity of outlet catalyst increases (catalyst with a residual activity still has an economic value), catalyst saving should be more and more intense. As far as possible, the optimal profile is shifted in direction of lower temperatures, whereas the optimal residence time is still the same. Then the optimal profile is isothermal at the level of minimum allowable temperature, whereas the catalyst is saved as its residence time in reactor decreases.     

Static tests on road bridge made from steel corrugated plates

Statische Versuche an Straßenbrücken aus Stahlwellblechen. Der Beitrag behandelt eine neue Bogenbrücke aus Stahlwellblechen, die Straßenbrücke über den Plawna‐Fluß zwischen Bystrzyca Klodzka und Ladek Zdroj in Stary Waliszow, Polen. Die Brücke ersetzt eine alte Steinbogenbrücke, die infolge der Flut im Jahre 1997 zerstört wurde. Die Stahlbrücke ist auf zwei Einzelfundamenten aus Stahlbeton gegründet. Ihre effektive Stützweite beträgt 10,00 m und ihre lichte Höhe 4,02 m. Es werden Versuchsergebnisse vorgestellt, die sich aus drei statischen Lastfällen nach vier Jahren Betriebsdauer ergaben. Die Mittelwerte der gemessenen Verschiebungen und Verformungen in ausgewählten Punkten und Elementen der Stahl‐Schalenkonstruktion lagen deutlich unter den für dieselbe Last errechneten Werten. Seit diese Art von Brückenentwürfen mehr und mehr für kleine und mittelgroße Brücken übernommen wird, können die aus den vorgestellten Versuchen gezogenen Schlußfolgerungen für die gesamte Klasse solcher Brückenkonstruktionen verallgemeinert werden.     

The structure and spectroscopy of lanthanide(III) complexes with picolinic acid N-oxide in solution and in the solid state

The spectroscopic characteristics and the crystal structure of Eu(III) complex with picolinic acid N-oxide ligand, picNO, at room and liquid-nitrogen temperatures are discussed. Studies concerning the Eu(III) ion luminescence (intensity, luminescence lifetime measurements, and excitation spectra of the ⁵D₀ → ⁷F₀ transition) are presented. The selective excitation luminescence spectroscopy of Eu(III) in the range of the ⁵D₀ → ⁷F₀ transition is used for the study of Eu/picNO complexes in solution equilibria. In the crystal the complex molecules build the two-dimensional structures with additional Na⁺ cations and water molecules. This structure consists of edge-sharing chains of Na distorted octahedral, interconnected by Eu polyhedra (distorted square antiprisms). The ligand, pyridine-2-carboxylate-1-oxide, coordinates to the Eu(III) ion as an ionic bidentate chelate, forming the Na[Eu(picNO)₄] complex of six-membered chelate rings with the bite angles of ca. 70.5°. The complex is symmetrical; the Eu(III) ion is eight-coordinated.     

Sorption of SPADNS azo dye on polystyrene anion exchangers: Equilibrium and kinetic studies

The sorption of SPANDS from aqueous solution onto the macroporous polystyrene anion exchangers of weakly basic Amberlyst A-21 and strongly basic Amberlyst A-29 in a batch method was studied. The effect of initial dye concentration and phase contact time was considered to evaluate the sorption capacity of anion exchangers. Equilibrium data were attempted by various adsorption isotherms including the Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models. A comparison of kinetic models applied to the adsorption rate constants and equilibrium sorption capacities was made for the Lagergren first-order, pseudo second-order and Morris–Weber intraparticle diffusion kinetic models. The results showed that the adsorption isotherm is in the good agreement with the Langmuir equation and that the adsorption kinetics of SPADNS on both anion exchangers can be best described by the pseudo second-order model.     

Multiscale probability density function analysis: non-Gaussian and scale-invariant fluctuations of healthy human heart rate

For a detailed characterization of intermittency and non-Gaussianity of human heart rate, we introduce an analysis method to investigate the deformation process of the probability density function (PDF) of detrended increments when going from fine to coarse scales. To characterize the scale dependence of the multiscale PDF, we use two methods: 1) calculation of Kullback-Leibler relative entropy; 2) parameter estimation based on Castaing's equation (B. Castaing et al, 1990). We compare scale-dependence of the increment PDFs between actual heart rate fluctuations and artificially generated Gaussian and non-Gaussian noise, including a widely used autoregressive model and a recently proposed multifractal model based on a random cascade process. Our analysis highlights an essential difference between heart rate fluctuations and those generated by other models. The outstanding feature of human heart rate is the robust scale-invariance of the non-Gaussian PDF, which is preserved not only in a quiescent condition, but also in a dynamic state during waking hours, in which the mean level of heart rate is dramatically changing. Our results strongly suggest the need for revising existing models of heart rate variability to incorporate the scale-invariance in the PDF.     

Unique very low-frequency heart rate variability during deep sleep in humans

We investigate heart rate variability (HRV) in the very low-frequency (VLF) range (0.003-0.04 Hz) during deep sleep in good sleepers. Spectral analysis of HRV during deep sleep reveals consistent peaks at <0.04 Hz. By using wavelet analysis, we find both stationary and nonstationary periodic patterns in the VLF range, the presence of which has been discussed but has not been fully established to date. Although the mechanism(s) behind the unique VLF oscillations remain to be fully explored, we conjecture that there is an endogenous rhythmic component in human HRV in the VLF range. Further, our results also suggest a need for caution in the interpretation of the VLF spectral power in HRV during deep sleep.     

Application of Freezing and Thawing in Apple (Malus domestica) Juice Extraction

The paper presents the results of the research on the impact of enzymatic liquefaction, freezing and thawing on the efficiency of juice pressure extraction from apple pulp and quality of the obtained juices. The research was conducted using three types of pretreatment prior the pressing: crushing and enzymatic liquefaction in temperature of 25 °C, crushing and enzymatic liquefaction in temperature of 45 °C and crushing followed by freezing and thawing of the pulp. The study included three varieties of apples. The juice was obtained using a laboratory basket press. It was determined that the pretreatment of the pulp as well as the varietal characteristics of the fruits have a significant impact on the efficiency of the pressure extraction process. The enzymatic treatment of the pulp, irrespective of the temperature at which it was conducted, significantly increased the efficiency of the process. No effect of the temperature (25 or 45 °C) of enzymatic treatment on the efficiency of the pressure extraction process was found. Pretreatment of the pulp based on freezing and thawing contributes to the increase of efficiency of pressing in the case of two apple cultivars, that is, Idared and Red Delicious. It was showed that total phenolic content, antioxidant activity, the soluble solids content and juice acidity (pH) depend on the pretreatment of the pulp and the varietal characteristics of apples. Following the application of pretreatment of the pulp, an increase was observed in the content of polyphenols and in the antioxidant activity of the juices obtained.     

Self-assembly of perylenediimide based semiconductor on polymer substrate

The continuous bi-layer composites consisting of top, ordered crystalline layer of perylenediimide derivative (2,9-di(pent-3-yl)-anthra[,1,9-def:6,5,10-d′e′f′]diisoquinoline-1,3,8,10-tetrone) - PTCDI-C5(3) and bottom poly(3-hexylthiophene-2,5-diyl) (P3HT) support were obtained from one solution, with a use of so called “two-step reticulate doping” method. Optical, atomic force and scanning electron microscopy images show that the top crystalline layer is made of relatively large, anisotropic domains composed of long, parallel crystals. The crystalline character of the surface layer of PTCDI-C5(3) grown on the P3HT film was confirmed by wide angle X-ray scattering measurements. Furthermore, the grazing-incidence angle X-ray diffraction experiments revealed that the self-assembly of PTCDI-C5(3) molecules on P3HT is dominated by π−π interaction between the conjugated perylene cores, and the stacks are parallel to the long axis of the crystals and to the polymer surface. The surface conductivity, measured along the long axis of the crystals was estimated to be ca. 2.4 10^− 8 Ω^− 1 square^− 1 at 285 K. Temperature dependence of the conductivity in the range 140-285 K reveal semiconductor-like behaviour with activation energy ca. 150 meV.