Bi4Ge3O12 single crystals were obtained using Czochralski growth method. Photoluminescence spectra were analyzed versus temperature from 12 to 295 K. Besides the previously observed emission bands at 610 and 820 nm, the new emission band at 475 nm was found by a careful temperature dependence measurement in the present study. The influence of basic and defect structure on the shape and position of the spectra versus temperature was discussed.
Understanding the effect of long-term drainage of peatland areas is helpful in future peatland management and regulations of water conditions. The aim of this work was to assess the current state of fen peatland soils in the Grójecka Valley (eastern part of the Wielkopolskie voivodeship, central Poland), affected by long-term agricultural use (pastures, meadows) since the 1960s and potentially by lignite open pit mining industry (KWB Konin) since 1980s. Field studies were carried out in 2015 in selected fen peatland areas. Soil material for laboratory analysis was collected from genetic horizons from four soil profiles. The surface horizons of studied organic and organo-mineral soils were built with well-developed moorsh material. They were classified as medium moorshiefied – MtII (profile 1, 3 and 4) and strongly moorshiefied – MtIII (profile 2). Obtained results of physical and physico-chemical analysis indicate that long-term peatland utilization connected with potential impact of the lignite mining, transformed mainly the upper horizons of studied organic and organo-mineral soils. However, despite obvious strong human impact on peatlands ecosystems, we cannot exclude the climate variables, what should be confirmed by long-term monitoring program. Furthermore, presented paper indicated that new subtype moorsh-muddy soils (in Polish: gleby murszowo-mułowe) within the type of gleyic soils should be implemented in the next version of Polish Soil Classification.
This work presents the results of a four-year study on the determination of the range of soil groundwater drainage caused by the operation of the Tomisławice lignite open-cast mine. The performed analyses covered the area of 9600 ha which included 24 villages. It was found that operation of Tomisławice open-cast mine caused noticeable changes of soil groundwater level in the areas adjacent to the excavation. It consequently resulted in considerable changes in soil water regimes types on grassland areas but it did not always lead to soil degradation processes. However, the deterioration of soils hydrological conditions may cause disappearance of certain hydrophilous grass species.
The paper presents physical and water properties of six soils located in the areas directly adjacent to “Drzewce” lignite open cast mine (KWB Konin). The conducted works included preparation of pits of various soil types in points characteristic to large and representative soil allotments. The selected soil types represented mineral and organic soils. Samples of disturbed and undisturbed structure were taken from various genetic horizons for laboratory analysis. Such properties as content of total carbon, texture, specific density, bulk density, total and drainage porosity, moisture, saturated hydraulic conductivity, the potential of water bonding, total and readily available water, and total retention were determined in the samples from the horizons of 0–100 cm. The investigated soils showed mostly sandy texture with few local loam insertions. Texture and the content of organic matter were the most important parameters which influenced all analyzed properties. Morphology and the properties of the examined soils as well as deep level of soil – ground water were decisive factors when categorizing them as a precipitation-water type. Such soils will not undergo degradation caused by the dehydrating depression cone of open cast mine.
The paper presents the characteristics of selected physical, chemical, and water properties of four mineral arable soils characterized with heavy and very heavy texture. Soil samples from genetic horizons of black earths from areas near Kętrzyn, Gniew and Kujawy, and alluvial soils from Żuławy were used. The following properties were determined in the samples of undisturbed and disturbed structure: texture, particle density, bulk density, porosity, natural and hygroscopic moistures, maximal hygroscopic capacity, saturated hydraulic conductivity, potential of water bonding in soil, total and readily available water, total retention in the horizon of 0–50 cm, drainage porosity, content of organic carbon and total nitrogen Parent rocks of these soils were clays, silts and loams of various origin. High content of clay fraction strongly influenced the values of all the analyzed properties. All the examined soils had high content of organic carbon and total nitrogen and reaction close to neutral or alkaline. High content of mineral and organic colloids and, what follows, beneficial state of top horizons’ structure, determined – apart from heavy texture – low soil bulk density and high porosity. The investigated soils were characterized by high field water capacity and wide scopes of total and readily available water. The saturated hydraulic conductivity was low and characteristic to heavy mineral arable soils. The parameter which influenced the variability of analyzed parameters most was texture.
The aim of this study was to evaluate the fruit quality of 13 Asian pear cultivars grown in climatic conditions of central Poland. The following cultivars were tested: ‘Chojuro’, ‘Hayatama’, ‘Hosui’, ‘Kosui’, ‘Yuan Huang’, ‘Nijisseiki’, ‘Dżin Li’, ‘Er Shi Shinge’, ‘Er Jang Li’, ‘Golden 20th’, ‘Min Czi Li’, ‘San Li’, and ‘Shinseiki’. Pears were harvested in Experimental Orchard of Research Institute of Horticulture in Dąbrowice (near Skierniewice). Fruits were stored for 10 weeks at 0 °C in regular atmospheric conditions. Flesh firmness (FF), total soluble solids (TSS), and titratable acidity (TA) were measured at harvest and after the storage followed with 1 and 7 days of shelf life (SL) at 18 °C. After the storage, the sensory evaluation was also performed. Among the tested cultivars, ‘Min Czi Li’ and ‘San Li’ were the most firm (above 45 N) and ‘Kosui’ was the least firm (below 28 N) at harvest time. High amount of TSS (above 11% in both seasons and harvest dates) was observed in ‘Chojuro’, ‘Hayatama’, ‘Kosui’, ‘Yuan Huang’, and ‘Er Jang Li’ pears. Low TSS (not more than 10.6% at harvest) was observed in ‘Nijisseiki’, ‘Dżin Li’, and ‘Er Shi Shinge’ cultivars. The large differences among cultivars were observed in TA. High TA was observed in ‘Nijisseiki’ (above 0.32% in all terms of analyses) and low TA in ‘Hayatama’ and ‘Kosui’ (below 0.14%). All of the evaluated cultivars can be stored for 10 weeks at 0 °C in regular atmosphere without major negative impact on their quality characteristics. Fruits showed a slight (sometimes significant) decrease in FF after storage and a slight or no changes in TSS and TA. In sensory evaluations, ‘Chojuro’, ‘Hayatama’, ‘Hosui’, ‘Kosui’, ‘Yuan Huang’, ‘Er Jang Li’, ‘Er Shi Shinge’, and ‘Shinseiki’ (mostly cultivars characterized by high TSS) obtained highest scores for the overall quality (above 5.0 points in 10 points scale).
In this work the physicochemical and biological properties of nanocrystalline TiO2 thin films were investigated. Thin films were prepared by magnetron sputtering method. Their properties were examined by X-ray diffraction, photoelectron spectroscopy, atomic force microscopy, optical transmission method and optical profiler. Moreover, surface wettability and scratch resistance were determined. It was found that as-deposited coatings were nanocrystalline and had TiO2-anatase structure, built from crystallites in size of 24 nm. The surface of the films was homogenous, composed of closely packed grains and hydrophilic. Due to nanocrystalline structure thin films exhibited good scratch resistance. The results were correlated to the biological activity (in vitro) of thin films. Morphological changes of mouse fibroblasts (L929 cell line) after contact with the surface of TiO2 films were evaluated with the use of a contrast-phase microscope, while their viability was tested by MTT colorimetric assay. The viability of cell line upon contact with the surface of nanocrystalline TiO2 film was comparable to the control sample. L929 cells had homogenous cytoplasm and were forming a confluent monofilm, while lysis and inhibition of cell growth was not observed. Moreover, the viability in contact with surface of examined films was high. This confirms non-cytotoxic effect of TiO2 film surface on mouse fibroblasts.