Polymer behavior under the influence of interfacial interactions

textThe properties of polymers, thin films or bulk, are profoundly influenced by interactions at interfaces with dissimilar materials. Thin, supported, polymer films are subject to interfacial instabilities, due largely to competing intermolecular forces, that cause them to rupture and dewet the substrate. The addition of nanoparticles (such as clay sheets, metallic or semiconductor nanocrystals, carbon nanotubes, etc.) to polymers can substantially affect bulk properties, such as the glass transition and viscosity, and influence the processability of the material. In this dissertation, we contribute to a fundamental understanding of the role of interfacial interactions on both the instabilities exhibited by polymer thin films and the properties displayed by polymer-nanoparticle mixtures. While conditions under which the destabilization of compositionally homogeneous thin films occurs are relatively well understood, the mechanisms of film stabilization in many two-component thin film systems are still unresolved. We demonstrate that the addition of a miscible component to an unstable film can provide an effective means of stabilization. The details of the stabilization mechanism are understood in terms of the compositional dependence of both the macroscopic wetting parameters and the effective interface potential for the system. We find that the suppression of dewetting in the system is not an equilibrium stabilization process and propose a mechanism by which the increased resistance to dewetting may occur. There is also significant interest in understanding the extraordinary property enhancement of polymers that are enabled by the addition of only small concentrations of nanoparticles. If these effects could be distilled down to a few simple rules, they could be exploited in the design of materials for specific applications. In this work, the influence of C60 nanoparticles on the bulk dynamical properties of three polymers is examined. Based on the findings from a range of measurement techniques, including differential scanning calorimetry, dynamic mechanical analysis, dynamic rheology and neutron scattering, we propose that the changes in the glass transition temperature for the polymer-C₆₀ mixtures can be understood in terms of a percolation interpretation of the glass transition. The proposed mechanism is also characterized computationally.Chemical Engineerin

Kantian Approaches to Animals and Obligations

In recent years, a number of competing theories have arisen regarding the moral significance of animals to Kant’s deontology, which has traditionally been viewed as unsympathetic towards animals. Based on an overview of how Kant himself positions animals in his moral system, primarily in the Doctrine of Virtue and Lectures on Ethics, I argue that his distinguishing of animals from humans on the basis of rationality is supported, but not to the extent that we are prevented from having moral obligations to animals. One popular reading of Kant only allows us to have indirect duties to animals as they lack rational nature and legislative wills. However, I find that these claims can only give us weak duties to animals and rest on tenuous empirical evidence. Christine Korsgaard, James Rocha, and others have advanced alternate interpretations of Kantian ethics that give us direct duties. I argue that a direct duties interpretation such as Korsgaard’s, which uses an alternative value-based framework rather than positing that animals possess a rational nature, is preferable as it gives us stronger duties with less empirically based grounds than indirect duties interpretations. In addition, I conclude that it gives us a satisfactory answer to certain problems, such as marginal cases, that arise from a rational-animal reading

Hierarchical simulations of hybrid polymer-solid materials

Complex polymer-solid materials have gained a lot of attention during the last 2-3 decades due to the fundamental physical problems and the broad spectrum of technological applications in which they are involved. Therefore, significant progress concerning the simulations of such hybrid soft-hard nanostructured systems has been made in the last few years. Simulation techniques vary from quantum to microscopic (atomistic) up to mesoscopic (coarse-grained) level. Here we give a short overview of simulation approaches on model polymer-solid interfacial systems for all different levels of description. In addition, we also present a brief outlook concerning the open questions in this field, from the point of view of both physical problems and computational methodologies

Submicrometer Pattern Fabrication by Intensification of Instability in Ultrathin Polymer Films under a Water-Solvent Mix

Dewetting of ultrathin (< 100 nm) polymer films, by heating above the glass transition, produces droplets of sizes of the order of microns and mean separations between droplets of the order of tens of microns. These relatively large length scales are because of the weak destabilizing van der Waals forces and the high surface energy penalty required for deformations on small scales. We show a simple, one-step versatile method to fabricate sub-micron (>~100 nm) droplets and their ordered arrays by room temperature dewetting of ultrathin polystyrene (PS) films by minimizing these limitations. This is achieved by controlled room temperature dewetting under an optimal mixture of water, acetone and methyl-ethyl ketone (MEK). Diffusion of organic solvents in the film greatly reduces its glass transition temperature and the interfacial tension, but enhances the destabilizing field by introduction of electrostatic force. The latter is reflected in a change in the exponent, n of the instability length scale, {\lambda} ~h^n, where h is the film thickness and n = 1.51 \pm 0.06 in the case of water-solvent mix, as opposed to its value of 2.19 \pm 0.07 for dewetting in air. The net outcome is more than one order of magnitude reduction in the droplet size as well as their mean separation and also a much faster dynamics of dewetting. We also demonstrate the use of this technique for controlled dewetting on topographically patterned substrates with submicrometer features where dewetting in air is either arrested, incomplete or unable to produce ordered patterns

Changes in the water inflow to the Central Pumping Station Bolko in Bytom

W 2008 r. minęło 20 lat pracy centralnego systemu odwadniania wyrobisk górniczych pięciu zlikwidowanych kopalń rud cynku i ołowiu w niecce bytomskiej. W wieloleciu 1989-2008 wydzielono sześć okresów, różniących się wielkościami dopływów do systemu. Sumaryczne dopływy wody do pompowni wahały się od 19,4 m3/min (2005) do 39,0 m3/min (1997). Po okresie wysokich dopływów 38,6-39,0 m3/min w latach 1996-1997, a także 30,3-30,4 m3/min w latach 2001-2002, od 2003 r. obserwuje się zdecydowanie niższe wartości 19,4-23,5 m3/min. Niższe dopływy do pompowni w stosunku do wielkości prognozowanej, równej 36,0 m3/min, spowodowały ucieczki około 5,0-6,0 m3/min wody w trakcie ich przekierowania po wyłączeniu pompowni głównych w rejonie wschodnim oraz dwie ucieczki wody z rejonu zachodniego do niżej leżących wyrobisk kopalni węglowej.In 2008 twenty years has passed by since the central drainage system of mine workings belonging to 5 closed zinc and lead ore mines in the Bytom Trough had started its work. In the years 1989-2008 six periods were distinguished that differed in the amount of water flowing into the system. Total water inflow to the pumping station ranged from 19.4 m3/min (2005) to 39.0 m3/min (1997). After the period of high water inflow 38.6-39.0 m3/min in the years 1996-1997, and also 30.3-30.4 m3/min in the period 2001-2002, significantly lower water inflows 19.4-23.5 m3/min have been observed since 2003. Lower water inflow to the pumping station in comparison with the expected 36.0 m3/min, led to escape of ca. 5.0-6.0 m3/min of water when its flow direction has been changed, after main pumping stations in the eastern area had been shut down, and two water escape from western area to the mine workings of coal mine lying below

The background of changes in water supply to the Bolko Central Pumping Station in Bytom

W 2016 r. minął dwudziesty ósmy rok pracy centralnego systemu odwadniania wyrobisk górniczych pięciu zlikwidowanych kopalń rud cynku i ołowiu w niecce bytomskiej. Sumaryczne dopływy wody do centralnej pompowni wahały się od 15,5 m3/min (2016) do 39,0 m3/min (1997). W wieloleciu 1989-2016 średni dopływ wody do pompowni wynosił 26,2 m3/min i był niższy o około 10,0 m3/min od wielkości prognozowanej, równej 36,0 m3/min. We wspomnianym wieloleciu wydzielono osiem okresów, różniących się wielkościami dopływów do systemu. Wysokie dopływy: 38,6-39,0 m3/min, 30,3-30,4 m3/min i 36,3-29,6 m3/min przypadły na lata: 1996-1997, 2001-2002 i 2010-2011. Niższe dopływy: 19,4-23,8 m3/min oraz 15,5-22,7 m3/min przypadły na lata 2003-2009 i 2012-2016. Przyczynami niższych dopływów wody do pompowni w ostatnim okresie były: niskie opady atmosferyczne, zmiany w gospodarce wodno-ściekowej w zlewni Rowu z Dąbrówki Wielkiej w południowo-wschodniej części Piekar Śląskich oraz likwidacja niektórych źródeł przesączania wody z powierzchni terenu w górotwór triasowy. Wyjaśnienie przyczyn zmian w dopływie wody do pompowni jest bardzo ważne w kontekście prognozowania maksymalnej możliwej wielkości dopływu wody do zlikwidowanych kopalń rud oraz ewentualnej zmiany sposobu pompowania wody w centralnej pompowni.In 2016 it has already been 28 years since the central system of water drainage in mine workings of five liquidated zinc and lead ore mines in Bytom Basin started. Summaric water inflow to the central pumping station ranged from 15.5 m3/min (2016) to 39.0 m3/min (1997). In the years 1989-2016 the average water inflow was 26.2 m3/min and was lower by ca. 10.0 m3/min from the forecasted value, which was estimated at 36.0 m3/min. In the mentioned period there were eight intervals distinguished, in which the amount of water inflow to the system was different. High inflow: 38.6- 39.0 m3/min, 30.3-30.4 m3/min and 36.3-29.6 m3/min were reported in the years: 1996-1997, 2001-2002 i 2010-2011. Lower inflows: 19.4-23.8 m3/min and 15.5-22.7 m3/min were reported in the years 2003-2009 and 2012-2016. Among the reasons for lower inflows to the pumping station in the last period were: low precipitation, changes in water supply and sewage disposal in the basin of Ditch from Dąbrówka Wielka in south-east part of Piekary Śląskie and liquidation of some sources of water infiltration from the surface to the Triassic mountain formation. Explanation of reasons for changes in water supply to the pumping station is very important in the context of forecasting maximum possible amount of water supply to the liquidated ore mines and possible change in the method of water pumping to the station

Translation of Russian realities in Master and Margarita in Polish and Slovak language

Nieprzekładalność to jeden z podstawowych problemów teorii tłumaczenia, który doczekał się wielu, często zupełnie różniących się od siebie analiz.Jednym z aspektów bezekwiwalentnej leksyki są realia, czyli zjawiska, będące częścią kultury danego narodu, które są nieobecne w innej kulturze. Realia, pojawiające się w tekstach literackich, pełnią ważną rolę, nadając kolorytu lokalnego i wprowadzając czytelnika przekładu w świat innej kultury.Jedną z powieści, w których przedstawiana rzeczywistość, a więc także realia, są nadzwyczaj ważnym elementem tekstu, jest Mistrz i Małgorzata Michaiła Bułhakowa. Analiza przekładu na język polski i słowacki rosyjskich realiów, pojawiających się w powieści Mistrz i Małgorzata ukazała dwie metody tłumaczeniowe, których wybór był być może uwarunkowany różnicami w historii związku Polski i Słowacji z Rosją i odmiennością kultur tych dwóch krajów. W wyniku różnic w sposobie tłumaczenia realiów polski i słowacki przekład konstruują nieco odmienne obrazy rosyjskiej rzeczywistości.Translation is the communication of the meaning of a source-language text by means of an equivalent target-language text. But not every elements of the text can be translate. Untranslatability is one of the main problems of the translation studies. A part of untranslatable words are little facts, traditions and rituals from daily life of some nation, which is characteristic for its culture. In Master and Margarita there is a lot of Russian culture facts, which make a problems in traslation. We can see different strategy of translation in Slovak and Polish version of Master and Margarita. It constructs different picture of Russian reality