Amenability of groups and GG-sets

This text surveys classical and recent results in the field of amenability of groups, from a combinatorial standpoint. It has served as the support of courses at the University of G\"ottingen and the \'Ecole Normale Sup\'erieure. The goals of the text are (1) to be as self-contained as possible, so as to serve as a good introduction for newcomers to the field; (2) to stress the use of combinatorial tools, in collaboration with functional analysis, probability etc., with discrete groups in focus; (3) to consider from the beginning the more general notion of amenable actions; (4) to describe recent classes of examples, and in particular groups acting on Cantor sets and topological full groups

Polyaniline/palladium nanohybrids for moisture and hydrogen detection.

Palladium nanoparticles display fascinating electronic, optical and catalytic properties, thus they can be used for various applications such as sensor fabrication. Conducting polymers such as polyaniline have also been widely used in sensor technology due to its cost effectiveness, versatility, and ease of synthesis. In this research, attention was given to unify the exceptional properties of these two materials and construct palladium nanoparticle coated polyaniline films to detect hydrogen and moisture. Electrochemical polymerization of aniline was carried out on gold sputtered epoxy resin boards. Polyaniline film was generated across a gap of 0.2 mm created by a scratch made on the gold coating prior to electrochemical polymerization. A palladium nanoparticle dispersion was prepared using sonochemical reduction method and coated on to polyaniline film using drop-drying technique. Polyaniline only films were also fabricated for comparative analysis. Sensitivity of films towards humidity and hydrogen was evaluated using impedance spectroscopy in the presence of the respective species. According to the results, polyaniline films exhibited an impedance drop in the presence of humidity and the response was significantly improved once palladium nanoparticles were incorporated. Interestingly, polyaniline only films did not respond to hydrogen. Nevertheless, palladium nanoparticle coated polyaniline films exhibited remarkable response towards hydrogen

Electrochemically synthesized polymers in molecular imprinting for chemical sensing

This critical review describes a class of polymers prepared by electrochemical polymerization that employs the concept of molecular imprinting for chemical sensing. The principal focus is on both conducting and nonconducting polymers prepared by electropolymerization of electroactive functional monomers, such as pristine and derivatized pyrrole, aminophenylboronic acid, thiophene, porphyrin, aniline, phenylenediamine, phenol, and thiophenol. A critical evaluation of the literature on electrosynthesized molecularly imprinted polymers (MIPs) applied as recognition elements of chemical sensors is presented. The aim of this review is to highlight recent achievements in analytical applications of these MIPs, including present strategies of determination of different analytes as well as identification and solutions for problems encountered

Yield and quality of winter wheat (Triticum aestivum L.) in response to different systems of foliar fertilization

Foliar fertilizers are increasingly used in agricultural practice to maximize the yield potential of T. aestivum. Foliar fertilization can effectively reverse nutritional deficiencies (macronutrients), and it can be used as the main method for supplying plants with the required micronutrients. The objective of this study was to determine the effect of various systems of foliar micronutrient and macronutrient fertilization on the yield and quality of wheat grain. A field experiment was carried out in 2012-2015, in the Agricultural Experiment Station in Bałcyny, owned by the University of Warmia and Mazury in Olsztyn. The highest grain yield (10.16 Mg ha-1) of winter wheat was noted in the treatment where foliar fertilizers were supplied in 5 applications. It was higher by 230-430 to 660 kg ha-1 than in plots where foliar fertilizers were supplied in 2 applications. Intensified foliar fertilization increased nitrogen (54%) and potassium (12%) concentrations, but decreased the magnesium (10%) content of winter wheat straw. The concentrations of phosphorus (0.34 g kg-1 dry matter (DM)), potassium (0.23 g kg-1 DM), calcium (0.40 g kg-1 DM) and sulfur (0.05 g kg-1 DM) in winter wheat grain increased in response to intensified foliar fertilization. Foliar application of liquid macronutrient and micronutrient fertilizers increased micronutrient concentrations in winter wheat straw (copper, zinc, manganese, iron), but decreased the micronutrient content of grain (copper, zinc, iron). Intensified foliar fertilization significantly reduced total protein content (1.1 g kg-1 DM) and gluten content (0.9%) and deteriorated protein quality. The influence of different foliar fertilization systems on the falling number was determined by precipitation levels during the heading and ripening of winter wheat. The rheological properties of dough (development, stability and softness) improved each year in response to intensified foliar fertilization with macronutrients and micronutrients

Yield and quality of winter wheat (Triticum aestivum L.) in response to different systems of foliar fertilization

Foliar fertilizers are increasingly used in agricultural practice to maximize the yield potential of T. aestivum. Foliar fertilization can effectively reverse nutritional deficiencies (macronutrients), and it can be used as the main method for supplying plants with the required micronutrients. The objective of this study was to determine the effect of various systems of foliar micronutrient and macronutrient fertilization on the yield and quality of wheat grain. A field experiment was carried out in 2012-2015, in the Agricultural Experiment Station in Bałcyny, owned by the University of Warmia and Mazury in Olsztyn. The highest grain yield (10.16 Mg ha-1) of winter wheat was noted in the treatment where foliar fertilizers were supplied in 5 applications. It was higher by 230-430 to 660 kg ha-1 than in plots where foliar fertilizers were supplied in 2 applications. Intensified foliar fertilization increased nitrogen (54%) and potassium (12%) concentrations, but decreased the magnesium (10%) content of winter wheat straw. The concentrations of phosphorus (0.34 g kg-1 dry matter (DM)), potassium (0.23 g kg-1 DM), calcium (0.40 g kg-1 DM) and sulfur (0.05 g kg-1 DM) in winter wheat grain increased in response to intensified foliar fertilization. Foliar application of liquid macronutrient and micronutrient fertilizers increased micronutrient concentrations in winter wheat straw (copper, zinc, manganese, iron), but decreased the micronutrient content of grain (copper, zinc, iron). Intensified foliar fertilization significantly reduced total protein content (1.1 g kg-1 DM) and gluten content (0.9%) and deteriorated protein quality. The influence of different foliar fertilization systems on the falling number was determined by precipitation levels during the heading and ripening of winter wheat. The rheological properties of dough (development, stability and softness) improved each year in response to intensified foliar fertilization with macronutrients and micronutrients

Yield and quality of winter oilseed rape in response to different systems of foliar fertilization

The aim of this study was to determine the effect of different systems of foliar fertilization on the yield of winter oilseed rape (Brassica napus L.), the mineral composition of post-harvest biomass and the processing suitability of seeds. In winter oilseed rape grown on boulder clay, intensified foliar fertilization increased seed yield (by 0.43-0.69 Mg ha-1 87% dry matter, DM), straw yield (by 0.59-1.69 Mg ha-1 DM), and decreased the harvest index (by 2-3%). The seeds of winter oilseed rape accumulated more N, P, Ca, Zn, Cu, Mn and Fe than straw. The concentrations of P, Mg and S were higher in straw than in seeds. Foliar fertilization increased the N, P and K content (by 2.0, 0.35 and 1.15 g kg-1 DM, respectively) and decreased the Mg and S content of straw (by 2.08 and 0.77 g kg-1 DM, respectively). A chemical analysis of seeds revealed significant changes only in the concentrations of K, S (increase by 0.57 and 0.55 g kg-1 DM, respectively) and P (decrease by 0.90 g kg-1 DM, respectively) under the influence of foliar fertilization. Intensified foliar fertilization increased the concentrations of Cu and Zn and decreased the levels of Mn and Fe in straw and seeds. The nutritional value of seeds deteriorated (crude fat content decreased by around 5.5 g kg-1 DM, but the composition of fatty acids (FAs), and the proportions of saturated FAs, monounsaturated FAs and polyunsaturated FAs were not significantly altered) with an increase in foliar fertilization levels. Foliar application of macronutrients and micronutrients improved the feed value of winter oilseed rape seeds. Intensified foliar fertilization reduced the content of alkenyl (by approx. 47%) and indole (by approx. 6%) glucosinolates in seeds, mostly due to a decrease in the concentrations of progoitrin, gluconapin and 4-OH-glucobrassicin

Nawożenie azotem a plon i jakość browarna jęczmienia jarego odmiany prestige

The aim of this study was to precisely quantify the effect of different level and time of nitrogen application on the field and malting quality of spring barley grain of cultivar Prestige. Source of results was the field experiment carried out in 2003-2005. The experiment was carried out with the split-plot method in 4 replications. 8 fertilization combinations were tested (0; 20; 40; 40 (20 + 20); 60; 60 (40 + 20); 80; 80 (60 + 20) kg N·ha-1). It was found that in soil of the good wheat complex at content Nmin. = 55-77 kg·ha-1 in layer 0-90 cm in spring high grain yields are obtained already at fertilization 40-60 kg N·ha-1. Considerably higher productivity of these rates is obtained when they were divided into two parts – presowing and that applied at 23 BBCH stage. Raw material of the malting cultivar (Prestige) collected under different conditions of weather (year with average total precipitation and wet year) and fertilization (N rates from 20 to 80 kg N·ha-1) is characterized by small variability of main qualitative index values of grain, malt and wort and comprehensive Q index according to EBC.Celem badań było szczegółowe skwantyfikowanie wpływu zróżnicowanego poziomu i terminu aplikacji azotu na plon i wartość browarną ziarna jęczmienia jarego odmiany Prestige. Źródłem wyników był eksperyment polowy przeprowadzony w latach 2003-2005. W doświadczeniu prowadzonym metodą split-plot, w 4 replikacjach, testowano 8 kombinacji nawozowych (0; 20; 40; 40 (20 + 20); 60; 60 (40 + 20); 80; 80 (60 + 20) kg N·ha-1). Stwierdzono, że na glebie kompleksu pszennego dobrego przy zawartości Nmin. = 55-77 kg·ha-1 w warstwie 0-90 cm wiosną uzyskuje się wysokie plony ziarna już przy nawożeniu 40-60 kg N·ha-1. Wyraźnie większą produkcyjność tych dawek osiąga się w przypadku ich podziału na dwie części – przedsiewną oraz zastosowaną w stadium 23 BBCH. Surowiec odmiany browarnej (Prestige) zebrany w różnych warunkach przyrodniczych (rok o przeciętnej sumie opadów i rok wilgotny) i nawozowych (dawki N od 20 do 80 kg N·ha-1) charakteryzuje się małym zróżnicowaniem wartości głównych wskaźników jakościowych ziarna, słodu i brzeczki oraz kompleksowym wskaźnikiem Q według EBC