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EN
The aim of this study was to determine the effects of sonication (S), convective freezing (F), convective freezing preceded by sonication (SF) as well as cryogenic freezing (N) on the osmo-microwave-vacuum drying kinetics, energy usage and properties of dried cranberries such as moisture content, moisture diffusion, water activity, density, porosity, thermal conductivity, thermal diffusivity, volumetric heat capacity, lightness, redness, yellowness, total differences in color, saturation and hue, hardness, cohesiveness, springiness and chewiness. Osmo-microwave-vacuum drying of cranberries took from 13.5 to 16.0 min. All initial treatments increased the moisture diffusivity and thus reduced the drying time. The most energy effective method was osmo-microwave-vacuum drying preceded by sonication (S) of fruits. Osmo-microwave-drying of cranberries subjected to convective freezing preceded by sonication (SF) resulted in the highest lightness (32.5 ± 0.5), redness (33.9 ± 0.7) and yellowness (11.3 ± 0.5) of fruits, as well as the lowest cohesion (the lowest resistant to stress associated with manufacturing, packaging, storage, and delivery). The lowest hardness, i.e. 12.3 ± 0.4 N and the highest cohesiveness and springiness, i.e. 0.38 ± 0.02 and 0.74 ± 0.03 of dried fruits, were noted for berries subjected to initial cryogenic freezing (N). Cryogenic freezing (N) combined with osmo-microwave-vacuum drying resulted in the largest color changes of fruits and the highest thermal conductivity. Sonicated and convectively frozen (SF) fruits were characterized by the highest thermal diffusivity. Sonication (S), convective freezing (F) and their combination (SF) significantly reduced the volumetric heat capacity of cranberry fruits.
EN
The characterization of organic matter (OM) in sedimentary rocks is important in many types of biological, geological and environmental research. The integrated use of microscopy and geochemistry, as here, is particularly useful in any attempt to define the origin and evolution of OM in sedimentary basins. The organic petrography and geochemistry different types of allogenic and authigenic OM from the Polish Outer Carpathian (POC) rocks were studied in present study to compare their genetic type, thermal maturity, depositional environment and post-sedimentation processes. Special attention was paid to redeposited coal clasts occurrences. The used techniques show differences in organic matter type originating from various sources. The organic petrography analysis shows that redeposited coal clasts (CC) and terrigenous organic matter (TOM) are composed predominantly of woody material (the gas-prone Type-III kerogen). Similar results were obtained during the Rock-Eval pyrolysis. Moreover, the GC-MS analysis of extracts indicated the additional source of OM, namely planktonic organic matter (POM) with oil-prone kerogen Type-I or II. This OM is in some cases high thermally mature and could potentially has allochthonous origin. The n-alkane, saturated and aromatic biomarker data revealed deposition of this POM in anoxic deltaic or close-shore sedimentary environments whereas the redeposited coal clasts were probably originally deposited in coal swamps as were the Upper Silesian bituminous coals.
EN
To intensify biogas production during anaerobic stabilization of organic matter in sludge, pretreatment is applied. The effect of pretreatment of excess activated sludge (AS) and excess aerobic granular sludge (GS) on biogas productivity (BP) and composition was investigated. The sludge was pretreated with homogenization (6,500 rpm for 0.5 min (H0.5) and 1 min (H1.0)) or ultrasound disintegration at 20 kHz (50% amplitude for 2 min (D50%_2.0) and 4 min (D50%_4.0), and 100% amplitude for 4 min (D100%_4.0)). BP of AS of GS without pretreatment was 603.3±5 dm3/kg TS (793.4±7 dm3/kg VS); that was 200.6±4 dm3/kg TS (480.8±6 dm3/kg VS). With disintegration, the BP of AS increased by 7.8% (650.4±10 dm3/kg TS) (D50%_2.0) and 16.1% (700.6±11 dm3/kg TS) (D100%_4.0), and that of GS increased by 7.0% (214.0±5 dm3/kg TS) (D50%_2.0) and 16.0% (232.8±5 dm3/kg TS) (D100%_4.0). With homogenization, BP increased by 2.0-3.0% (AS) and 1.6-3.2% (GS).
EN
The aim of study was to determine the influence of sonication and freezing on the kinetic of the microwave-vacuum drying, energy consumption and physical properties of whole cranberries as well as evaluate the applicability of sonication instead of freezing in order to change their physical properties and the drying kinetic of whole cranberries. Microwave-vacuum drying of whole cranberries with/without initial treatments took from 12 ± 1 to 14.5 ± 0.5 minutes. All of treatments did not significantly shorten the drying time of cranberries. However, they increased SMER values even by 31%. Despite of cryogenic freezing, all of treatments significantly increased the values of Dew. Sonication combined with drying allowed to obtain dried berries characterized by the lowest cohesiveness (0.19±0.02), springiness (0.62±0.02) and chewiness (3.4±0.8 N), while cryogenic freezing combined with drying allowed to obtain dried fruits characterized by highest springiness (0.75±0.03) and low chewiness (3.3±0.5 N). The highest lightness (32.2±0.7), redness (32.6±0.8), and yellowness (11.1±0.7) were found for fruits subjected to initial convective freezing before drying. The efficiency of sonication in color change was comparable to cryogenic freezing and much lower than convective freezing. All of initial treatments increased such thermal properties of dried cranberries as thermal conductivity and thermal diffusivity.
EN
The paper presents the coupled electro-mechanical problem. In the numerical analysis of the issue, piezoelectric solid-to-shell transition elements were applied. They combine three-dimensional or hierarchical shell piezoelectric elements with piezoelectric first order elements. The mentioned first order of the element refers to the field of transversal displacements of an element. The mechanical field of the discussed piezoelectric elements may correspond to: the model of three-dimensional theory of elasticity, hierarchical shell models of higher orders or the first order shell model. The electrical field of the potential may be modelled with hierarchical dielectric first order models or higher in transverse direction or with a three-dimensional theory. Effectiveness of modification of algorithms of classical piezoelectric elements was assessed in this paper. To perform such an assessment, curves of convergence of hp method in model tasks are presented. Curves obtained with the use of classical and modified piezoelectric transition elements were set and compared.
PL
Praca dotyczy sprzężonego problemu elektro-mechanicznego. W analizie numerycznej zagadnienia zastosowane zostały piezoelektryczne elementy przejściowe o charakterze bryłowopowłokowym. Łączą one ze sobą trójwymiarowe (lub hierarchiczne powłokowe) elementy piezoelektryczne z elementami piezoelektrycznymi pierwszego rzędu. Wspomniany pierwszy rząd elementu odnosi się do pola przemieszczeń poprzecznych elementu. Pole mechaniczne omawianych elementów piezoelektrycznych może odpowiadać modelom trójwymiarowej teorii sprężystości, hierarchicznym modelom powłokowym wyższych rzędów lub modelowi powłokowemu pierwszego rzędu. Elektryczne pole potencjału modelowane może być za pomocą hierarchicznych modeli dielektrycznych rzędu pierwszego lub wyższych w kierunku poprzecznym lub teorią trójwymiarową. W niniejszej pracy dokonana została ocena efektywności modyfikacji wprowadzonych do algorytmów klasycznych elementów piezoelektrycznych. W celu takiej oceny przedstawione są krzywe zbieżności metody hp w zadaniach modelowych. Zestawione ze sobą i porównane zostały krzywe uzyskane z wykorzystaniem klasycznych i zmodyfikowanych, piezoelektrycznych elementów przejściowych.
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