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A new design to reduce coercive field Ec by fabricating nanolaminate Hf0.5Zr0.5O2/ZrO2 thin films is used, followed by a ensuing annealing process at 700 C. High-resolution TEM imaging detects tetragonal-like domain walls between orthorhombic polar regions. These walls decrease the potential barrier of polarization reversal in HfO2 based films compared with to the conventional domain walls with a single non-polar spacer, causing about a 40% decrease in Ec. Permittivity exhibits substantial increase near the Ec compared to the conventional Hf0.5Zr0.5O2 films justifying the higher mobility of domain walls. The tetragonal-like regions served as grease easing the movement of the domain wall and reducing Ec.

The paper presents the results of the research into the impact of anti-wear added to emulsion mist on the geometrical state of the machined surface of stainless steel after turning. In the research, the following machining conditions were compared: dry machining and cooling with compressed air, emulsion mist, emulsion mist + Crodafos O4A-LQ-(MH) and emulsion mist + Crodafos EHA-LQ-(MH). In the first stage, the influence of modifiers on roughness parameters of the machined surface were established. The aim of the second stage was to submit the machined material to microroentgenospectral analysis. The presence of chemical elements on the machined material surface for the aforementioned conditions of machining was analysed. Research results indicate that the application of cooling with emulsion mist with modifiers reduces the roughness parameters of the machined material even up to 80%. Adequately selected conditions of forming emulsion mist forms border layer, beneficially influencing the cutting conditions.

Two types of TiO2 based materials have been prepared from titanium oxysulfate hydrate via precipitation by cold solution of sodium hydroxide and drying at room temperature. The structural changes (especially crystallization into anatase, resp. sodium titanates) during heating up to 1000 degrees C were studied together with adsorption properties of prepared and annealed materials towards radionuclides Sr-85 and Cs-134. It was found that amorphous and non-annealed materials are able to adsorb higher amount of radionuclides, annealing always leads to decrease of adsorption efficiency. The amount of exchangeable sodium cations was found as the second factor determining adsorption properties of studied titania based materials.

Scintillation properties of Czochralski-grown Gd3(Al5-xGax)O12:Ce (x = 2.3, 2.6, 3.0) single crystals were investigated. With increasing Ga content in garnet host, the radioluminescence band due to 5d1 → 4f emission transition was blue-shifted due to a decrease in the crystal field splitting of the 5 d levels. At 662 keV γ rays, the LY value of 47,000, 55,100 and 51,900 ph/MeV was obtained for Gd3Al2.7Ga2.3O12:Ce, Gd3Al2.4Ga2.6O12:Ce and Gd3Al2Ga3O12:Ce, respectively. In spite of a lower LY value, Gd3Al2.7Ga2.3O12:Ce shows good energy resolution of 4.1% due to its proportionality of LY. The ratio of LY values under excitation with α- and γ-rays (α/γ ratio) was also determined. The fast component decay time with relative intensity of 146 ns (66%), 142 ns (76%) and 112 ns (76%) was measured in the scintillation decay of Gd3Al2.7Ga2.3O12:Ce, Gd3Al2.4Ga2.6O12:Ce and Gd3Al2Ga3O12:Ce, respectively.

Although particulate organic and elemental carbon (OC and EC) are important constituents of the suspended atmospheric particulate matter (PM), measurements of OC and EC are much less common and more uncertain than measurements of e.g. the ionic components of PM. In the framework of atmospheric research infrastructures supported by the European Union, actions have been undertaken to determine and mitigate sampling artefacts, and assess the comparability of OC and EC data obtained in a network of 10 atmospheric observatories across Europe. Positive sampling artefacts and analytical discrepancies have been taken into account to generate a robust data set, from which we established the phenomenology of carbonaceous aerosols at regional background sites in Europe. Across the network, TC and EC annual average concentrations range from 0.4 to 9 mg C/m3, and from 0.1 to 2 mg C/m3, respectively. TC/PM10 annual mean ratios range from\n0.11 at a Mediterranean site to 0.34 at the most polluted continental site, and TC/PM2.5 ratios are slightly greater at all sites (0.15e0.42). EC/TC annual mean ratios range from 0.10 to 0.22, and do not depend much on PM concentration levels, especially in winter. Seasonal variations in PM and TC concentrations, and in TC/PM and EC/TC ratios, differ across the network, which can be explained by seasonal changes in PM source contributions at some sites.

The scintillation characteristics of Czochralski-grown GdLu2Al2Ga3O12:Ce and GdY2Al2Ga3O12:Ce single crystals were compared for gamma-ray detection. At 662-keV gamma-rays, light yield (LY) of 30700 photons/MeV obtained for GdLu2Al2Ga3O12:Ce is higher than that of 27 200 photons/MeV obtained for GdY2Al2Ga3O12:Ce, while its energy resolution is inferior (14% versus 10.6%) due to a larger nonproportionality of LY. Scintillation decays were measured using the time-correlated single photon counting technique. A fast component decay time of 48 ns with relative intensity of 71% obtained for GdLu2Al2Ga3O12:Ce is superior to that of 106 ns (57%) for GdY2Al2Ga3O12:Ce. The coincidence time spectrum was measured in reference to a fast BaF2 scintillator, and coincidence time resolution was discussed.

The article analyses discourses of Jewish refugee criminality in Czechoslovakia after the end of the First World War. In the Czech-language press, Jewish refugees were depicted as the perpetrators of serious crimes, including improper trading, which took advantage of the shortages of food and other basic commodities, smuggling, and forging currency. The author treats these accusations as a type of moral panic which not only reflected dramatic wartime and post-war changes and economic distress but which was also part of the process of nation-building. The discursive exclusion of Jewish refugees therefore not only built on antisemitic stereotypes and established notions of Jewish criminality, but also contributed to the formation of the borders, citizenship, and legal order of the new Czechoslovak state.

Free-molecular gas flow in cylindrical channels (capillaries) in various schemes of molecule scattering by channel walls in view of surface diffusion is considered. The problem of separation of gas mixtures in their flow through membranes with nanopores is studied. The problem of uniform deposition of thin films on the inner surface of the fine cylindrical channel is discussed.

We read with interest the article by Nguyen et al. on the association between diabetes mellitus (DM) and mortality among patients with tuberculosis (TB) published recently in this journal.1 The authors investigated the association between DM and all causes of mortality among a large number of patients undergoing anti-tuberculosis treatment in California, USA. They concluded that TB patients with DM had a greater risk of death during anti-tuberculosis treatment than those without DM. The authors should be congratulated for highlighting this very important topic and for their efforts to collect and analyse such a large amount of data while trying to correct for important covariables. Although we agree with most of their conclusions, we would like to draw your readers’ attention to one point of issue.

Motivated by the analysis of neural net models between integer and rational weights, we introduce a so-called cut language over a real digit alphabet, which contains finite beta-expansions (i.e. base-beta representations) of the numbers less than a given threshold. We say that an infinite beta-expansion is eventually quasi-periodic if its tail sequence formed by the numbers whose representations are obtained by removing leading digits, contains an infinite constant subsequence. We prove that a cut language is regular iff its threshold is a quasi-periodic number whose all beta-expansions are eventually quasi-periodic, by showing that altogether they have a finite number of tail values. For algebraic bases beta, we prove that there is an eventually quasi-periodic beta-expansion with an infinite number of tail values iff there is a conjugate of beta on the unit circle. For transcendental beta combined with algebraic digits, a beta-expansion is eventually quasi-periodic iff it has a finite number of tail values. For a Pisot base beta and digits from the smallest field extension Q(beta) over rational numbers including beta, we show that any number from Q(beta) is quasi-periodic. In addition, we achieve a dichotomy that a cut language is either regular or non-context-free and we show that any cut language with rational parameters is context-sensitive.