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A complex study of the operation of supported ionic liquid membranes from practical point of view was made. It was shown that supported ionic liquids are selective for the binary mixture of CH4/CO2. Unfortunately, the literature reports certain pure ionic liquid data, which are mainly focused on CO2 and there is lack of data for CH4. The main problem seems to be the lack of data of the diffusion coefficients of gases in ionic liquids and, consequently, there are no correlations avialable between the transport properties and the molecular properties of the gas and of the IL.. The data available in literature are measured and calculated for pure ionic liquids only but there is no reasonable way how to apply them to the supported ionic liquid membranes. All the literature data sets overestimate at least twice the membrane performance in terms of pemeability and selectivity. Such a discrepancy brings the supported ionic liquid membranes into an inconvenient position from the point of view of practical application because it is not possible to design a process reliably although the supported ionic liquid membranes are comparable in separation characteristics to the best polymeric membrane (see Robeson plot Fig. 7). The reasons why the theoretical models overpredict the real values of permeation fluxes may be summarized below: o The mass transfer resistance of the support is not negligible, as often assumed o Some pores of the support are not opened for permeation o The structure of the support obstructs the maximal saturation of the liquid with the gas or in other words the initial concentration of the gas in the liquid does not reach the expected equilibrium value. None of these reasons should be totally excluded. A simple model of transport of gases through the liquid membrane in permeation cell was suggested. It showed that in the used pressure range (150-350kPa), the mass transfer coefficient may be assumed constant with reasonable accuracy. The model could be applied in the scale-up of the process because it takes into account the decrease of the driving force that occurs along the membrane. This decrease is not really significant in the lab scale process, where the membrane area is small, but it may be important in larger scale processes, especially when the high enrichment of retentate is required. Generally, it can be concluded that the ionic liquid membranes are convenient for gas separation processes, but it is necessary to rely on the data connected to the supported liquid membranes themselves rather than on the data of pure (free) ionic liquids.

Abstract The attachment of bubbles onto a collecting surface plays a critical role in flotation which is utilised for the separation of mineral ores, coal or plastic materials. While mineral flotation deals with fine particles and larger bubbles, this work is focused on the opposite case of an interaction of a single rising bubble (Db

Abstract The experimental data of speed of sound and refractive index for eight binary liquid mixtures of nitromethane with: 1,1,2,2-tetrachloroethane, 1,1,1-trichloroethane, trichloromethane, 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, 1-chlorobutane and 1-chloropentane, have been measured at temperatures in the range of 298.15–318.15 K and atmospheric pressure. From the experimental data of densities and speeds of sound, the isentropic compressibilities and the excess isentropic compressibilities were calculated and from the experimental data of refractive indices, the deviation in refractive indices and the molar refractions have been computed. These excess properties of the binary mixtures were correlated by the Redlich–Kister type polynomials using a robust regression along a gnostic influence function. Speeds of sound and isentropic compressibilities have been compared with calculated values from Jacobson free length theory (FLT), Nomoto’s relation (NR), Zhang Junjie’s relation (JR), Van Deal’s ideal mixing relation (IMR) and Impedance dependence relation. The ability of different theoretical (n, ρ) mixing rules (Lorentz–Lorenz, Gladstone–Dale, Arago–Biot, Edwards and Eykman) to predict the refractive indices was evaluated. The experimental and calculated results are discussed in terms of molecular interactions and structural effects between components of mixtures.

The development of 1,8-naphthalimide derivatives as DNA-targeting anticancer agents is a rapidly growing area and has resulted in several derivatives entering into clinical trials. One of original recent developments is the use of boron clusters: carboranes and metallacarboranes in the design of pharmacologically active molecules. In this direction several naphthalimide-carborane and metallacarborane conjugates were synthesized in the present study. Their effect on a cancer cell line - cytotoxicity, type of cell death, cell cycle, and ROS production were investigated. The tested conjugates revealed different activities than the leading members of the naphthalimides family, namely mitonafide and pinafide. These derivatives could induce G0/G1 arrest and promote mainly apoptosis in HepG2 cell line. Our investigations demonstrated that the most promising molecule is N-{[2-(3,3'-commo-bis(1,2-dicarba-3-cobalta(III)-closo-dodecaborate-1-yl)ethyl]-1'-aminoethyl)}-1,8-naphthalimide] (17). It was shown that 17 exhibited cytotoxicity against HepG2 cells, activated cell apoptosis, and caused cell cycle arrest in HepG2 cells. Further investigations in HepG2 cells revealed that compound 17 can also induce ROS generation, particularly mitochondrial ROS (mtROS), which was also proved by increased 8-oxo-dG level in DNA. Additionally to biological assays the interaction of the new compounds with ct-DNA was studied by CD spectra and melting temperature, thus demonstrating that these compounds were rather weak classical DNA intercalators.

Cobalt oxide catalysts deposited on titania–ceria supports were examined in deep ethanol oxidation and N2O decomposition. Supports with various molar ratio of CeO2/TiO2 were prepared by the sol–gel method and cobalt components were introduced by impregnation and subsequent calcination. The supports and catalysts were examined by chemical analysis, X-ray diffraction, nitrogen physisorption, H2-TPR, and NH3-TPD. It was found out that the ethanol conversion at 200 °C is proportional to the CeO2/(CeO2 + TiO2) molar ratio in the supports, and temperature T 50 of ethanol oxidation is proportional to the amount of components reducible in the temperature range of 20–500 °C. A comparison of specific catalytic activities in both ethanol oxidation and N2O decomposition proved a lower rate of N2O decomposition than that of oxidation of ethanol (approximately 25 times). The findings confirmed the great importance of the supports surface areas on specific activity of cobalt catalysts in both reactions. The obtained results showed that ceria is the best support of cobalt oxides for both deep ethanol oxidation and N2O decomposition when reaction rates are related to unit amount of active component in the catalysts.

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.

Abstract Saponification occurring in paint layers of artworks represents a serious degradation process affecting the appearance and stability of paintings. Formation of metal soaps is mostly reported as a consequence of the interaction of lead white or zinc white with oil binder. We found the distinct symptoms of saponification in paint layers consisting of lead-tin yellow type I and egg yolk binder in a panel painting from the 15th century. This scarce finding induced the study of interactions between lead-tin yellow type I with three different binders: (i) egg yolk tempera, (ii) emulsion of egg yolk and oil, and (iii) oil. The interactions were studied in long-term model experiments using infrared spectroscopy (FTIR) and powder X-ray diffraction (XRD). Based on the results, a set of mixed lead carboxylates of the series Pb(C16)2-x(C18)x, where x = 0; 0.25; 0.5; 0,75; 1; 1.5 and 2, was synthesised as reference materials suitable as a basis for proper identification of neo-formed lead soaps by FTIR and XRD. The formation of lead soaps was detected already within 1 month of reaction in egg yolk containing binders, whereas no soap was formed during 6 months of the experiment in the oil mixture. The neo-formed soaps are various mixed lead carboxylates containing both palmitate (C16) and stearate (C18) in one crystal structure and the proportion of carboxylate anions is affected by the type of the binder. We found the C16:C18 ratio in mixed lead carboxylates is higher in egg yolk tempera samples in accordance with the more abundant palmitic acid in egg yolk fat. On the other hand, the lower C16:C18 ratio in emulsion binder correlates with increased content of stearic acid, suggesting contribution of both binders, i.e. egg yolk and oil, to the soap formation.

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.