X-Ray diffraction, mossbauer spectroscopy, and magnetoelectric effect studies of multiferroic Bi5Ti3FeO15 ceramics

Bi5Ti3FeO15 ceramics belongs to multiferroic class of materials. In this work it was prepared by solidstate sintering method and investigated by X-ray di raction, Mössbauer spectroscopy, and magnetoelectric effect measurements. As it was proved by X-ray di raction studies the single-phase Bi5Ti3FeO15 compound was obtained. The Mössbauer investigations revealed paramagnetic character of the compound at room temperature as well as at 80 K. Magnetoelectric measurements were carried out at room temperature using lock-in dynamic method and they proved presence of magnetoelectric coupling in this material. Additional magnetoelectric studies were carried out after subsequent electric poling of the sample. It was found that the maximum value of the coupling coe cient was almost twice bigger than in the case without the initial poling and reached a value of ME 20.7 mV cm1 Oe1

Low-frequency electromagnetic field influences human oral mucosa keratinocyte viability in response to lipopolysaccharide or minocycline treatment in cell culture conditions

The aim of the current study was to investigate the influence of low-frequency electromagnetic field (LF-EMF) exposure on viability parameters of oral mucosa keratinocytes cultured in in vitro conditions. The effect of LF-EMF stimulation on cell viability was also specified in the simultaneous presence of lipopolysaccharide (LPS) infectious agent or minocycline (Mino) anti-inflammatory agent. Viability parameters such as early-, late apoptosis and necrosis of keratinocytes were analysed by the flow cytometry method (FCM).The exposure of human oral keratinocyte cell cultures to LF-EMF acting alone or combined with LPS/minocycline agents caused changes in the percentage of cells that undergo programmed or incidental cell death. The overall obtained results are compiled in a graphical form presented in Fig. 1

Multiferroic Cobalt Ferrite-Lead Iron Tungstate Composites

The paper presents dielectric, magnetic and magnetoelectric properties of multiferroic bulk composites based on $CoFe_2O_4$ ferrite and $Pb(Fe_{2//3}W_{1//3})O_3$ relaxor. X-ray diffraction analysis and scanning electron microscopy observations of ceramic samples revealed two-phase composition and fine grained microstructure with uniformly distributed ferromagnetic and ferroelectric phases. Dielectric permittivity measured in a temperature range 218-773 K at frequencies of 10 Hz-2 MHz exhibits high and broad maxima attributed to dielectric relaxation. The hysteresis determined in a temperature range 4-393 K for magnetic field changing from - 80 kOe to 80 kOe is typical of hard magnetic materials. Saturation magnetizations and coercivities were found to decrease with increasing temperature. The courses of zero field cooled and field cooled magnetization versus temperature curves measured in the temperature range 4-393 K imply spin glass behavior of the ferrite and antiferromagnetic transition of the relaxor at low temperatures. The ferrite-relaxor composite shows high magnetoelectric voltage coefficient which distinctly increases with increasing frequency of ac magnetic field and is slightly higher for higher ac and dc magnetic fields

The problem of fallow vegetation contamination with heavy metals in rural administrative units of Psary and Ploki

W artykule dokonano analizy określenia zawartości metali ciężkich w roślinności odłogów dwóch sołectw gminy Trzebinia: Psarów i Płok. Odłogowanie niesie ze sobą istotne zmiany w fitocenozie. Zmiany te mają przeważnie negatywny charakter dla rolnictwa. Rośliny pobierają metale ciężkie z roztworu glebowego poprzez system korzeniowy. Ich pobór jest aktywny przez system korzenny (szczególnie Pb) i pasywny przez liście zwłaszcza ( w przypadku Zn, Cu). Problem toksycznej obecności metali ciężkich w roślinach ww. sołectw ma charakter wieloletni i jest wynikiem antropogenicznego oddziaływania człowieka na środowisko przez różnorakie formy działalności przemysłowej, górniczej i przetwórczej lokalnych surowców leżących na terenach silnie przekształconych przez przemysł wydobywczy i przetwórczy. Otrzymane wyniki stężenia kadmu w Psarach i Płokach w materiale roślinnym nieznacznie przekroczyły dopuszczalną normę zawartości pierwiastka dla pasz zgodnie z Rozporządzeniem Ministra Rolnictwa i Rozwoju Wsi ≤1 mg/kg s.m., co oznacza, że roślinność badanego obszaru nie może być wykorzystana na cele paszowe. Zawartość ołowiu w pobranym materiale roślinnym nie przekroczyła przywołanej normy. Otrzymane wyniki zawartości cynku i miedzi w materiale roślinnym nie przekroczyły dopuszczalnych zawartości tych pierwiastków dla pasz zaproponowanych przez IUNG. W Płokach wykazano dodatni kierunek zależność pomiędzy zawartością ołowiu w glebie i w roślinach.The study aimed at analysing the content of heavy metals in the vegetation of fallow lands of two rural administrative units in the municipality of Trzebinia, namely Psary and Płoki. Fallowing results in significant changes in phytocenosis. The changes generally have a detrimental effect on agriculture. Plants take up heavy metals from the soil solution through the root system. Their uptake by the root system (especially Pb) is active and passive by leaves, especially in the case of Zn, Cu. The problem of the toxic presence of heavy metals in plants found in the afore-mentioned administrative units is long-term in nature and results from the anthropogenic impact on the environment. The human influence assumes various forms of industrial, mining and processing activities of local raw materials located in areas heavily transformed by the extractive and processing industries. The obtained results of the cadmium concentration found in plant material from Psary and Płoki slightly exceeded the permissible concentrations of the element for feed, according to the Regulation of the Minister of Agriculture and Rural Development, i.e. ≤1 mg/kg dry weight. This means that the vegetation of the area cannot be used for feed purposes. The lead content of the collected plant material did not exceed the reference standard. The obtained results of zinc and copper contents in plant material were lower than the permissible content of these elements for feeds proposed by IUNG. In Płoki, a positive relationship between the content of the lead in soil and in plants was determined

Two families of European beaver are being threatened by a planned A4 motorway

Praca przedstawia dyskusję możliwych rozwiązań sytuacji dwóch rodzin bobrowych bytujących w Czarnej Rzeczce (zlewnia Wisłoka) w powiecie Ropczycko-Sędziszowskim. Ich siedliska przecina planowana autostrada A4. Pomimo sporych trudności autorzy postulują przeniesienie koryta Czarnej Rzeczki łącznie z oczkami wodnymi. Stworzy to szansę na przeniesienie się tam opisywanych zwierząt. Planowany odcinek autostrady A4 trzeba bezzwłocznie budować. Kompensacja przyrodnicza powinna być szerzej wykorzystywana w praktyce ochrony przyrody.Due local human settlement the motorway can not be placed in other position. The author discussed possible solution of the problem. They recommend moving the beaver habitats. The new Czarna Rzeczka River bed could be made (including two small water bodies). In this case, there would be change, the animals colonize them

Compositional dependence of hyperfine interactions and magnetoelectric coupling in (BiFeO3)x-(BaTiO3)1–x solid solutions

In this work the compositional dependence of hyperfine interactions and magnetoelectric coupling in (BiFeO3)x-(BaTiO3)1–x solid solutions where x = 0.5–0.9 fabricated from commercial BaTiO3 in terms of the solid-state sintering method at various temperatures and over different time periods is described. In general, as the content of BaTiO3 increases, a decrease in the hyperfine magnetic field (Bhf) at 57Fe nuclei was observed. However, for samples exhibiting lower homogeneity in which the ions of Bi3+ and Fe3+ are replaced by Ba2+ and Ti4+ with lower probability, higher values of Bhf are obtained. For the sample where x = 0.6 that exhibits the coexistence of rhombohedral, regular and tetragonal phases, the highest value of the αME coefficient (3.57 mV/A) was observed, which is more than three times higher when compared to the hitherto published results

Efekt magnetoelektryczny w warstwowym kompozycie Ni0.3Zn0.62Cu0.08Fe2O4 - PbFe0.5Nb0.5O3

The magnetoelectric effect in multiferroic materials has been widely studied for its fundamental interest and practical applications. The magnetoelectric effect observed for single phase materials like Cr2O3, BiFeO3, and Pb(Fe0.5Nb0.5)O3 is usually small. A much larger effect can be obtained in composites consisting of magnetostrictive and piezoelectric phases. This paper investigates the magnetoelectric effect of a multilayer (laminated) structure consisting of 6 nickel ferrite and 7 PFN relaxor layers. It describes the synthesis and tape casting process for Ni0.3Zn0.5Cu0.08Fe2O4 ferrite and relaxor PbFe0.5Nb0.5O3 (PFN). Magnetic hysteresis, ZFC - FC curves and dependencies of magnetization versus temperature for PFN relaxor and magnetoelectric composite were measured with a vibrating sample magnetometer (VSM) in an applied magnetic field up to 85 kOe at a temperature range of 10 – 400 K. Magnetoelectric effect at room temperature was investigated as a function of a static magnetic field (0.3 - 6.5 kOe) and the frequency of sinusoidal magnetic field (0.01 - 6.5 kHz). At lower magnetic field, the magnetoelectric coefficient increases slightly before reaching a maximum and then decreases. The magnetoelectric coefficient aME increases continuously as the frequency is raised, although this increase is less pronounced in the 1-6.5 kHz range. Maximum values of the magnetoelectric coefficient attained for the layered composites exceed about 50 mV/(Oe cm).Materiały kompozytowe wykazujące efekt magnetoelektryczny są obecnie szeroko badane zarówno dla celów poznawczych jak i aplikacyjnych. Szczególny nacisk kładzie się na kompozyty ferrytowo – relaksorowe, w których efekt magnetoelektryczny jest znacznie większy niż w materiałach jednofazowych. W opracowaniu przedstawiono technologię wytwarzania wielowarstwowego kompozytu ceramicznego składającego się z magnetycznych warstw ferrytu Ni0.3Zn0.62Cu0.08Fe2O4 rozdzielonych warstwami ferroelektryka PbFe0.5Nb0.5O3. Przedstawiono wyniki badań właściwości magnetycznych otrzymanego kompozytu. Badania te przeprowadzono przy użyciu magnetometru wibracyjnego w szerokim zakresie temperatur (10K- 400K) w polu magnetycznym dochodzącym do 85 kOe. Wykonano pomiary efektu magnetoelektrycznego w temperaturze pokojowej w zależności od częstotliwości zmiennego pola magnetycznego (0.01 - 6.5 kHz) oraz natężenia stałego pola magnetycznego (0.3 - 6.5 kOe). Współczynnik magnetoelektryczny najpierw rośnie, osiąga maksimum a następnie lekko maleje ze wzrostem natężenia stałego pola magnetycznego. Współczynnik magnetoelektryczny badanego kompozytu rośnie ze wzrostem częstotliwości sinusoidalnego zmiennego pola magnetycznego osiągając maksymalną wartość około 50 mV/(Oe cm)

Mössbauer effect studies of Dy(Fe0.7-xNixCo0.3)2 intermetallics

Abstract A consequence of the Fe/Ni substitution in the series of Dy(Fe0.7 xNixCo0.3)2 was studied in the presented paper. The synthesis and X-ray analysis (300 K) of the Dy(Fe0.7 xNixCo0.3)2 system were performed. The cubic, MgCu2-type, Fd3m crystal structure was evidenced for this solid solution. 57Fe Mössbauer effect measurements for the system were carried out at 77 K. The obtained crystallographic lattice parameters and the hyperfine interaction data are presented. The magnetic hyperfine field values form a separate branch of the Slater-Pauling curve situated above the branch corresponding to the Dy(Fe1 xCox)2 intermetallics

Water supply and sewerage infrastructure in the Krakow Metropolitan Area over the period 2003-2013

Water supply and sewerage infrastructure, which characterizes a particular territorial unit, is one of the key elements of its economic development. The sustainability index of water and sewage management system of the specific area, for which the total lengths of both water supply system and sewerage system are similar as it can be clearly seen, looking at the urban units of the Krakow Metropolitan Area, is absolutely vital. The apparent disparity between the lengths of both the water supply system and sewage system in the urban-rural and rural communes with a particularly significant shortage of sewerage infrastructure was shown. This proves the unsustainability of water and sewage management system in the area. A significant improvement in the condition of infrastructure in the analysed decade should be noted. This is clearly linked with the main objective of the Water Framework Directive and the subsequent participation of the analyzed area of KMA in the EU funds and other aid programs which aim at achieving a good level of water by 2015