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The annealing behavior of (1-x)BiMg0.5Ti0.5O3−xBiZn0.5Ti0.5O3 [(1-x)BMT−xBZT] perovskite solid solutions synthesized under high pressure was studied in situ via X-ray diffraction and piezoresponse force microscopy. The as prepared ceramics show a morphotropic phase boundary (MPB) between the non-polar orthorhombic and ferroelectric tetragonal states at 75 mol. % BZT. It is shown that annealing above 573 K results in irreversible changes in the phase diagram. Namely, for compositions with 0.2 < x < 0.6, the initial orthorhombic phase transforms into a ferroelectric rhombohedral phase. The new MPB between the rhombohedral and tetragonal phases lies at a lower BZT content of 60 mol. %. The phase diagram of the BMT−BZT annealed ceramics is formally analogous to that of the commercial piezoelectric material lead zirconate titanate. This makes the BMT−BZT system promising for the development of environmentally friendly piezoelectric ceramics.

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Milk is a food of high nutritional value processed by heat treatment. Heat treatment of milk is a technological process designed to inhibit the growth of microorganisms and extend the shelf life of products. The heating process directly affects the molecular structure of whey proteins by the process of denaturation. It leads to the formation of a whey protein−casein polymer complex. Based on these facts, milk heat-treatment conditions should be controlled during milk processing. This work focuses on describing the whey protein denaturation process and formation of the complex of whey protein with casein. The effect of heat treatment on individual milk protein fractions alpha-casein (α-cas), beta-casein (ß-cas), kappa-casein (κ-cas), beta-lactoglobulin (ß-lg) and alpha-lactalbumin (α-la) was studied by SDS-PAGE. Formation of the whey protein−casein polymer complex increased significantly (p < 0.05) on increasing the temperature and duration of the heat treatment.

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Precipitation of nanocrystallites of cobalt-aluminium layered double hydroxides in a magnetic field has been studied. In a magnetic field perpendicular to the substrate, dense and homogeneous films have been obtained. Magnetic anisotropy of the crystallites is explained by deviation from the statistical cation distribution in favour of honeycomb-like coordination of cobalt.

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Allium vegetables belong to the most widespread and commonly grown vegetables in Slovakia. In this study, we dealt with the content of selected heavy metals (Zn, Mn, Cr, Cu, Ni, Pb, and Cd) in cultivated garlic (Záhorský, Lukan, Makoi), onion (Amika, Red Matte, Diamant), and leek (Bavaria, Golem, Tango). We determined the total content of heavy metals (aqua regia), and available-mobile forms of heavy metals (1 M NH4NO3) in soils. Analytical final procedure was flame AAS. The results were compared with the limit values given by the Law no. 220/2004 (valid in the SR) as well as threshold values proposed by the European Commission (EC) (2006). Gained result showed that the total content of Cd (1.26 mg.kg-1) as well as the available mobile forms of Cd (0.16 mg.kg-1) and Pb (0.64 mg.kg-1) was exceeded on the soil on which Allium species were grown. Determined contents of heavy metals in garlic were in the range of 0.03-0.07 mg Cd.kg-1 FM (fresh matter), 0.02-0.11 mg Pb.kg-1 FM (fresh matter), in onion ranged from ND (not detected) to 0.03 mg Cd.kg-1 FM (fresh matter), 0.09-0.2 mg Pb.kg-1 FM (fresh matter), and in leek were in the range of, 0.07-0.13 mg Cd.kg-1 FM (fresh matter), and 0.3-0.5 mg Pb.kg-1 FM (fresh matter). Based on the obtained BAF values, we can conclude that the genus Allium does not belong to the accumulator of evaluated hazardous metals. Safe food production requires constant monitoring of hazardous metals in raw materials of plant origin, as these metals can have serious negative effects on human health.

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We report a new antiferromagnetic radical-anion salt (RAS) formed from 7,7,8,8-tetracyanquinonedimethane (TCNQ) anion and 2-amino-5-chloro-pyridine cation with the composition of (N-CH3-2-NH2-5Cl-Py)(TCNQ)(CH3CN). The crystallographic data indicates the formation of (TCNQ)2 .- radical-anion π-dimers in the synthesized RAS. Unrestricted density functional theory calculations show that the formed π-dimers characterize with strong π-stacking "pancake" interactions, resulting in high electronic coupling, enabling efficient charge transfer properties, but π-dimers cannot be stable in the isolated conditions as a result of strong Coulomb repulsions. In a crystal, where (TCNQ)2 .- π-dimers bound in the endless chainlets via supramolecular bonds with (N-CH3-2-NH2-5-Cl-Py)+ cations, the repulsion forces are screened, allowing for specific parallel π-stacking interactions and stable radical-anion dimers formation. Measurements of magnetic susceptibility and magnetization confirm antiferromagnetic properties of RAS, what is in line with the higher stability of ground singlet state of the radical-anion pair, calculated by means of the DFT. Therefore, the reported radical-anion (N-CH3-2-NH2-5Cl-Py)(TCNQ)(CH3CN) solvate has promising applications in novel magnetics with supramolecular structures.

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A post-synthesis thermal treatment of metastable phases in the high-pressure stabilised perovskite BiFe1-yScyO3 system results in the irreversible formation of polymorphs which represent novel polar and antipolar structures with interesting magnetic properties. Such annealing-stimulated polymorphism is believed to be a general phenomenon which can be found in other systems.

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Wetlands are fragile, dynamic systems, transient at larger temporal scales and strongly affected by long-term human activities. Sustaining at least some aspects of human management, particularly traditional grazing, would be especially important as a way of maintaining the "necessary" disturbances for many endangered species. Traditional ecological knowledge represents an important source of information for erstwhile management practices. Our objective was to review historical traditional knowledge on wetland grazing and the resulting vegetation response in order to assess their relevance to biodiversity conservation. We studied the Pannonian biogeographic region and its neighborhood in Central Europe and searched ethnographic, local historical, early botanical, and agrarian sources for historical traditional knowledge in online databases and books. The findings were analyzed and interpreted by scientist, nature conservationist and traditional knowledge holder (herder) co-authors alike. Among the historical sources reviewed, we found 420 records on traditional wetland grazing, mainly from the period 1720-1970. Data showed that wetlands in the region served as basic grazing areas, particularly for cattle and pigs. We found more than 500 mentions of habitat categories and 383 mentions of plants consumed by livestock. The most important reasons for keeping livestock on wetlands were grazing, stock wintering, and surviving forage gap periods in early spring or mid-late summer. Besides grazing, other commonly mentioned effects on vegetation were trampling and uprooting. The important outcomes were vegetation becoming patchy and remaining low in height, tall-growing dominant species being suppressed, litter being removed, and microhabitats being created, such as open surfaces of mud and water. These historical sources lay firm foundations for developing innovative nature conservation management methods. Traditional herders still holding wetland management knowledge could contribute to this process when done in a participatory way, fostering knowledge co-production.

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The aim of the study was to investigate the antibiotic resistant E. coli strains isolated from bioaerosols and surface swabs in a slaughterhouse as a possible source of poultry meat contamination. The highest air coliforms contamination was during shackling, killing and evisceration of poultry. The strains showed resistance to ampicillin (89%), ceftiofur (62%) and cefquinome (22%), while resistance to ampicillin with sulbactam was only 6%. Resistance to streptomycin and gentamicin was detected in 43% vs. 14% isolates; to tetracycline 33%; to chloramphenicol and florfenicol in 10% vs. 18% isolates; to cotrimoxazol in 35% isolates; to enrofloxacin in 43% isolates. The higher MIC of ceftazidime (3.6 mg x l(-1)) and ceftriaxon (5.2 mg x l(-1)) revealed the presence of ESBLs in 43% of isolates. From 19 selected phenotypically ESBL positive strains, 16 consisted of CMY-2 genes, while CTX-M genes were not detected by PCR. Maldi tof analysis of selected E. coli showed a clear clonal relatedness of environmental strains from various withdrawals.

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A novel polymeric one-dimensional compound Cu(tn)Cl2 (tn = 1,3-diaminopropane) was prepared and structurally characterized, and its spectral, magnetic, thermodynamic, and thermal properties were studied. The unique structure shows ladderlike chains composed of Cu(II) atoms and chloro bridging ligands [Cu(-mu(3)-Cl-)Cu2] running along the crystallographic c axis. The coordination geometry about copper (4 + 2) approximates that of a strongly elongated octahedron. The equatorial plane of the coordination octahedron is formed by a chelate N-bonded tn ligand and two chloro ligands. One of the chloro ligands is terminal, and the other one, mu3-Cl-, forms two additional longer bonds to the neighboring copper atoms and thus occupies the axial octahedral positions. The electronic ground state of the Cu(II) ion is of d(z)2 symmetry and suggests the activation of intraladder and interladder Cl...H-N hydrogen bonds as exchange paths that form a two-dimensional pattern of a triangular symmetry. The interaction due to the hydrogen bonds seems to play an important role in molecular packing and magnetic coupling. The studies of magneto-structural correlations including electron paramagnetic resonance measurements and thermodynamic and magnetic properties revealed a two-dimensional character of magnetic correlations with the effective intralayer exchange coupling J/k(B) approximately -3 K. No phase transition to the ordered state has been observed down to 60 mK. Cu(tn)Cl2 with the interlayer coupling J' approximately 10(-3)J and moderate intralayer interaction represents an excellent example of a two-dimensional magnetic system.