Water from mining drainage is turbid because of suspensions. We tested the hypothesis that the chemical composition as well as shape and size of particles in suspensions of natural origin affect the density and functional diversity of zooplankton. The suspensions were analyzed with atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and optical microscopy. Elements found in the beidellite clays were also identified in the mineral structure of the particles. As the size of the microparticles decreased, the weight proportions of phosphorus, sulfur, and chlorine increased in the suspensions. These conditions facilitated the biomass growth of large and small microphages and raptorials. As the size of the nanoparticles decreased, the shares of silicon, aluminum, iron, and magnesium increased. These conditions inhibited raptorials the most. Ecosystem functionality was the highest with intermediate suspension parameters, which were at the lower range of the microphase and the upper range of the nanophase. The functional traits of zooplankton demonstrate their potential for use as sensitive indicators of disruptions in aquatic ecosystems that are linked with the presence of suspensions, and they facilitate gaining an understanding of the causes and scales of the impact of suspensions.

Bimetallic AZ31/6060 joints were produced by compound casting. The process involved pouring liquid magnesium alloy onto a solid aluminum alloy insert placed in a mold. Inserts with and without a zinc surface layer were used. For an insert with no Zn layer, the bonding zone was characterized by a nonhomogeneous microstructure. In the area adjacent to the AZ31, there was a eutectic (c and a(Mg)). In the area close to the 6060 alloy, two continuous layers of the c and b phases were detected. When a 6060 insert with a Zn layer was used, the bonding zone was mainly composed of Mg-Al-Zn phases. The joint without a Zn interlayer had low shear strength . The presence of the Zn interlayer caused a significant increase in the joint strength (39.8-46.6 MPa). The micro-indentation data suggest a less brittle fracture character of the bonding zone with a Zn layer.

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The paper presents results of studies on the crystallite sizes of oxide layer formed during a long-term operation on steel at an elevated temperature. This value was determined by a method based on analysis of the diffraction line profile, according to a Scherrer formula. The oxide layer was studied on a surface and a cross-section at the inner site on the pipe inlet, at the fire and counter-fire wall of the tube. X-ray studies were carried out on the inner surface of a tube (in a flowing medium environment), then the layer's surface was polished and the diffraction measurements repeated to reveal differences in the originated oxides layer. X-ray phase analysis was performed by the use of a SEIFERT 3003 T/T X-ray diffractometer, with a cobalt source of λCo = 0.17902 nm wavelength. X-ray diffraction measurements were performed in the 20 ÷ 120• range of angles with an angular step of 0.1• . To interpret the results the diffractograms were described by a pseudo Voigt curve using the Analyze software. A computer software and the DHN PDS, PDF4+2009 crystallographic database were used for the phase identification. The results showed that the crystallite sizes have an effect on the properties of the oxide. It has been shown that the outer oxide layer having larger crystallites, is more porous and thus more brittle.

Carbon nanotubes because of their high mechanical, optical or electrical properties, have found use as semiconducting materials constituting the reinforcing phase in composite materials. The paper presents the results of the studies on the mechanical properties of polymer composites reinforced with carbon nanotubes (CNT). Three-point bending tests were carried out on the composites. The density of each obtained composite was determined as well as the surface roughness and the resistivity at room temperature.Moreover the surface studies on an atomic forces microscope (AFM) and X-ray studies (phase composition analysis, crystallite sizes determination) were carried out on such composites. Measurements of the surface topography using the Tapping Mode method were performed, acquiring the data on the height and on the phase imaging. The change of intensity, of crystallite size and of half-value width of main reflections originating from carbon for composites have been determined using the X-ray analysis.Carbon nanotubes constituting the reinforcement for a polymer composite improve the mechanical properties and conductivity of the composite.Keywords: carbon nanotubes, AFM, surface topography, polymer composites, mechanical Nanorurki węglowe ze względu na wysokie właściwości mechaniczne, optyczne czy elektryczne znalazły zastosowanie jako faza wzmacniająca materiałów kompozytowych. W pracy przedstawiono wyniki badań właściwości mechanicznych kompozytów polimerowych wzmacnianych nanorurkami węglowymi (CNT). Na kompozytach została przeprowadzona próba trójpunktowego zginania. Określono gęstość każdego z otrzymanych kompozytów, wyznaczono chropowatość powierzchni na profilometrze oraz rezystywność w temperaturze pokojowej.Dla każdego z kompozytów przeprowadzono również badania powierzchni na mikroskopie sił atomowych (AFM), badania rentgenograficzne (analiza składu fazowego, określenie wielkości krystalitów). Przeprowadzono pomiary topografii powierzchni metodą Tapping Mode zbierając dane z wysokości i obrazowania fazowego. Za pomocą analizy rentgenograficznej określono zmianę intensywności, wielkości krystalitów oraz szerokości połówkowej refleksów głównych pochodzących od węgla dla nanorurek różnie modyfikowanych.Nanorurki węglowe stanowiące zbrojenie dla kompozytów polimerowych poprawiają właściwości mechaniczne oraz przewodność kompozytu.