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Aqueous solutions of conventional temperature-responsive amphiphilic polymers undergo a coil–globule conformational transition around the lower critical solution temperature (LCST) that causes the polymer surfaces to become hydrophobic and the polymers to aggregate together. Isocyanate polymers with alkylated oligo(ethylene oxide) side chains are expected to have rigid main chains and, thus, do not undergo the coil–globule structural transition, but they have recently been reported to exhibit temperature-responsive properties. In this study, molecular dynamics was used to calculate the agglomeration tendencies of two chains of poly(alkylated tri(ethylene oxide)isocyanate) (PRTEOIC, where R = methyl (Me) or ethyl (Et)) in aqueous solution to elucidate the LCST phenomenon in the absence of coil–globule conformational transition. Our MD simulations showed that aggregation also occurs in rod polymers. Furthermore, we found that both (PMeTEOIC)2 and (PEtTEOIC)2 showed parallel agglomeration of the two molecular chains with increasing temperature, but only (PMeTEOIC)2 showed a metastable T-shaped agglomeration in the middle temperature range. The crossing-point temperature (TCRP) at which the density of the first hydrophobic hydration shell around the sidechain alkyl group equals the bulk water density is a useful indicator for predicting the LCST of rod polymers with dense side chains terminated by alkyl groups.

The aim of this work was to investigate the possibility of doping copper sulfide Cu2S with selected fifth-group elements, potentially having a positive effect on the thermoelectric properties of the resulting materials. For the selected model structures, theoretical calculations and an analysis of the electronic structure and changes in the enthalpy of formation due to doping were performed using the WIEN2k package employing the Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method within density functional theory (DFT) formalism. Polycrystalline materials with the nominal composition of Cu32S15X1 (X = P, As, Sb, Bi) were synthesized in quartz ampoules, then sintered using the spark plasma sintering (SPS) technique and "SPS melting" method. The chemical and phase compositions of the obtained sinters were studied by X-Ray diffraction (XRD) and scanning electron microscopy (SEM). Additionally, investigations of thermoelectric properties, i.e., electrical conductivity, Seebeck coefficient and thermal conductivity in the temperature range 300–920 K, were performed. The results of this study indicate that only phosphorus is successfully incorporated into the Cu₂S structure. [ABSTRACT FROM AUTHOR]

Zeolite Y is one of the earliest known and most widely used synthetic zeolites. Many experimental investigations verify the valuable ion exchange capability of this zeolite. In this study, we assessed the effects of ion exchange on its vibrational spectra. We applied classical lattice dynamics methods for IR and Raman intensity calculations. Computed spectra of optimized zeolite Y structures with different cations were compared with experimental data. The spectra obtained in this study are in agreement with previous experimental and computational studies on zeolites from the faujasite group.

Aqueous solutions of conventional temperature-responsive amphiphilic polymers undergo a coil–globule conformational transition around the lower critical solution temperature (LCST) that causes the polymer surfaces to become hydrophobic and the polymers to aggregate together. Isocyanate polymers with alkylated oligo(ethylene oxide) side chains are expected to have rigid main chains and, thus, do not undergo the coil–globule structural transition, but they have recently been reported to exhibit temperature-responsive properties. In this study, molecular dynamics was used to calculate the agglomeration tendencies of two chains of poly(alkylated tri(ethylene oxide)isocyanate) (PRTEOIC, where R = methyl (Me) or ethyl (Et)) in aqueous solution to elucidate the LCST phenomenon in the absence of coil–globule conformational transition. Our MD simulations showed that aggregation also occurs in rod polymers. Furthermore, we found that both (PMeTEOIC)2 and (PEtTEOIC)2 showed parallel agglomeration of the two molecular chains with increasing temperature, but only (PMeTEOIC)2 showed a metastable T-shaped agglomeration in the middle temperature range. The crossing-point temperature (TCRP) at which the density of the first hydrophobic hydration shell around the sidechain alkyl group equals the bulk water density is a useful indicator for predicting the LCST of rod polymers with dense side chains terminated by alkyl groups. [ABSTRACT FROM AUTHOR]

This is a review of research conducted by the Center for Interdisciplinary Studies and the Copernicus Center for Interdisciplinary Studies in the field of the history of philosophy of nature and the history of philosophy of science in Poland in the inter-war period. In spite of the domination of positivistic philosophy that tended to ignore philosophy of nature, this kind of philosophizing was quite popular in Poland. The review begins with a summary of works related to the history of science, and then deals, in some detail, with works on the theory of evolution and the theory of relativity, especially with their philosophical aspects. The remaining part of the review is devoted to the principal personalities of that period, namely: Władysław Heinrich, Władysław Natanson, Tadeusz Grabowski, Marian Smoluchowski, Zygmunt Zawirski and Joachim Metallmann.

High temperature corrosion of thermoelectric materials is one of the most important issues linked with their application for power generation, especially in terrestrial conditions. The high chemical affinity of elements composing thermoelectric material to oxygen results in continuous degradation at high temperatures of most state-of-the-art materials. This issue is also well recognized in the case of antimonide skutterudites. The simplest way to protect against this process is the use of coatings. Complicated geometry of thermoelectric module favors coatings that can be deposited in a simple way on an assembled module. Such an opportunity, besides good thermal stability and appropriate thermal and electrical properties, is provided by amorphous silicon oxycarbide Si-O-C coatings. In this work, the results on Si-O-C coatings deposited on In0.4Co4Sb12 skutterudite are presented. The influence of heat treatment temperature and substrate roughness on the deposited layer is shown. Protective properties of the Si-O-C layer are presented by comparison of electrical conductivity and Seebeck coefficient of coated and uncoated samples, before and after isothermal oxidation in air at 430 °C for 24 h. In such conditions, the uncoated samples are distinctly oxidized (weight gain of 2.4%) with strongly affected electrical properties, while the coated samples show a slight weight gain of 0.1% and almost unchanged electrical properties. [ABSTRACT FROM AUTHOR]

There has been a long-standing debate in philosophical literature about the relationship of predictability and determinism. Some philosophers have claimed that determinism implies predictability; some have claimed the opposite and the others that there are no direct implication relations between these two concepts. According to the above, there are various notions of determinism and predictability at work in the philosophical literature. In contrast, in scientific tradition, the belief that any deterministic system is predictable has long history and is based on the power of the intuitions lying behind the concept of physical determinism, confirmed by many experiments. In this essay, the author focuses on the Laplacean vision for determinism and predictability (or more precisely on what he takes to be such a vision). While many forms of predictability are inconsistent with this vision, he argues that a suitably modified notion of predictability, defined within a framework of model notion of physical determinism, is implied by the Laplacean concept of determinism and, after some modifications, by other modern theories in physics, chemistry and related sciences. It is also argued, that such modified concept of predictability is consistent with common practice of scientists, and any attempt to find out whether a given scientific theory is deterministic, should be accompanied by careful analysis and appropriate modification of constituent elements of modern notion of determinism.

Recenzja książki: Leon M. Lederman, Christopher T. Hill, Symmetry and the Beautiful Universe, L.M. Lederman, Ch.T. Hill, “Symmetry and the beautiful universe”, Prometheus Books, New York (2004), ss. 363.

Recenzja książki: Robert B. Laughlin, A Different Universe: Reinventing Physics from the Bottom Down, Basic Books, New York, Hardcover 2005, Paperback 2006, ss. 254.