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EN
The study involved 17 species of freshwater molluscs. The concentration of heavy metals (Cu, Zn, Pb, Co, Cd andHg) in soft tissues was determinedfor 14 species, while the concentration of heavy metals in shells was determinedfor 16 species. Totally, 110 samples of soft tissue and 119 samples of shells were analysed. The statistical analysis of the qualitative data concerning concentration of metals in shells indicated a clear distinction between snails and bivalves. The only exception is Unio crassus, which was assigned to a three-point cluster together with snails. With respect to snails, this may be because the analysis was performed only on one sample. The results of this study can be significant both for palaeontological research and palaeoenvironmental research. If we have a few shell fragments available, it can be generally concluded, based on geochemical analysis of heavy metals in shells, which shell fragments belong to bivalves and which to snails. It is also possible to assess geochemical conditions of ancient ecosystems. Obviously, the given results are preliminary and they suggest necessity of further research.
PL
Badaniami objęto 17 gatunków mięczaków słodkowodnych, z czego dla 14 gatunków oznaczono koncentracje metali ciężkich (Cu, Zn, Pb, Co, Cd i Hg) w tkankach miękkich, a dla 16 gatunków oznaczono stężenia tych pierwiastków chemicznych w muszlach. Łącznie dysponowano wynikami analiz koncentracji metali w 110 próbkach tkanek miękkich i w 119 próbkach muszli. Gatunkami, których tkanki miękkie i muszle najlepiej reagują na zmiany koncentracji metali ciężkich w wodzie i osadach dennych, okazały się: Anodonta anatina, Dreissena polymorpha, Lymnaea stagnalis, Pseudoanodonta complanata i Viviparus contectus. Drugą grupę, odzwierciedlającą w mniejszym stopniu poziomy metali w środowisku, stanowią cztery gatunki: Viviparus viviparus, Sphaerium solidum, Unio pictorum oraz Unio tumidus. Gatunkami najlepiej odzwierciedlającymi poziomy metali w środowisku w poszczególnych układach środowiskowych są: (1) tkanki - woda: Viviparus contectus, Anodonta anatina oraz Viviparus viviparus, (2) tkanki - osady: Anodonta anatina, Pseudoanodonta complanata i Viviparus contectus, (3) muszle - woda: Dreissena polymorpha, Unio pictorum i Lymnaea stagnalis, (4) muszle - osady: Viviparus viviparus, Dreissena polymorpha i Sphaerium solidum. W wodzie powierzchniowej wszystkie sześć badanych metali możemy kontrolować poprzez analizę muszli Dreissena polymorpha, a w osadach dennych Cu, Zn, Pb, Cd i Hg poprzez analizę tkanek oraz Co poprzez analizę muszli Anodonta anatina. Te dwa gatunki wydają się podstawowe do dalszych prac. Dwa gatunki uważa się za gatunki uzupełniające w dalszych pracach. Są to: Lymnaea stagnalis (w wodzie możemy kontrolować Cu, Zn, Pb, Cd poprzez analizę muszli, a w osadach Cu, Pb, Cd poprzez analizę muszli oraz Zn poprzez analizę tkanek), Viviparus contectus (w wodzie możemy kontrolować Cu, Co, Cd poprzez analizę tkanek i Pb poprzez analizę muszli, a w osadach Cu, Zn, Co i Cd poprzez analizę tkanek). W toku dalszych prac należy zrezygnować z gatunków, które od 2001 r. są na liście gatunków chronionych w Polsce. Są to: Sphaerium rivicola, Sphaerium solidum, Unio crassus, Pseudoanodonta complanata oraz Anodonta cygnea.
EN
The research was applied to 17 species of freshwater molluscs, for 14 species the concentration of heavy metals (Cu, Zn, Pb, Co, Cd and Hg) was marked in soft tissues, and for 16 species the concentration of these metals was marked in shells. This study is based on the analysis of 110 samples of soft tissues and 119 samples of shells. The species that best react to the changes in concentration of the heavy metals in water and sediments are: Anodonta anatina, Dreissena polymorpha, Lymnaea stagnalis, Pseudoanodonta complanata and Viviparus contectus. The second group, which is less related with the environment, are four species: Viviparus viviparus, Sphaerium solidum, Unio pictorum and Unio tumidus. The species most related with the environment in individual arrangements are: (1) tissues - water: Viviparus contectus, Anodonta anatina and Viviparus viviparus, (2) tissues - sediments: Anodonta anatina, Pseudoanodonta complanata and Viviparus contectus, (3) shells - water: Dreissena polymorpha, Unio pictorum and Lymnaea stagnalis, (4) shells - sediments: Viviparus viviparus, Dreissena polymorpha i Sphaerium solidum. In the surface water we can control all six analyzed metals through the shell analysis of Dreissena polymorpha, and in the bottom sediments we can control the concentration of Cu, Zn, Pb, Cd i Hg by soft tissues analysis and Co by shell analysis of Anodonta anatina. These two species are crucial for the future research. Two other species are considered as supplementary. Those are: Lymnaea stagnalis (in water we can control the concentration of Cu, Zn, Pb, Cd by shell analysis, and in sediments we can control Cu, Pb, Cd by shell analysis and Zn by soft tissue analysis), Viviparus contectus (in water we can control the concentration of Cu, Co, Cd by tissues analysis and Pb by shell analysis, and in sediments we can control Cu, Zn, Co i Cd by tissues analysis). In the future research one should resig from using five species that are under protection in Poland since 2001. Those are: Sphaerium rivicola, Sphaerium solidum, Unio crassus, Pseudoanodonta complanata and Anodonta cygnea.
3
Content available Eigenproblems in nanomechanics
EN
The paper is semitutorial in nature to make it accessible to readers from a broad range of disciplines. Our particular focus is on cataloging the known problems in nanomechanics as eigenproblems. Physical insights obtained from both analytical results and numerical simulations of various researchers (including our own) are also discussed. The paper is organized in two broad sections. In the second section the attention is focused on the analysis of quantum dots. The analysis of electronic properties of strained semiconductor structures is reduced here to the solution of a linear boundary value problem (the classical Helmholtz wave equation). In Sec 3, we provide, intermixed with a literature review, details on various methods and issues in calculation free vibrations/loss of stability for carbon nanotubes. The effect of various parameters associated with the material anisotropy are addressed. Typically classical continuum mechanics, which is intrinsically size independent, is employed for calculations.
EN
The paper aims to investigate the effect of aluminium foam filling of hemispherical steel shell on its dynamic response, accounting for the blast pressure modelling. The considered structures subjected to uniformly distributed pressure, rigidly connected with a steel plate, are considered. True material stress–strain curves for shell and foam filling are assumed in calculations. The problem is solved by FEM using ANSYS software. The time relations of strain energy and effective stresses for different simulations of blast pressure are determined and compared for steel shells and shells filled with aluminum foam.
PL
Celem niniejszego artykułu było stwierdzenie, w jakim stopniu tkanki miękkie i muszle Anodonta anatina (L.) (szczeżuja pospolita) odzwierciedlają zmiany poziomów Cu, Zn, Pb, Co, Cd i Hg w wodzie powierzchniowej i osadach dennych (frakcja poniżej 0,20 mm) ujścia Odry. Materiał do badań laboratoryjnych został pobrany w latach 1999 i 2000 z obszaru ujścia Odry (19 stanowisk) oraz z jeziora Miedwie (jedno stanowisko). Na każdym stanowisku oznaczano koncentracje metali w wodzie powierzchniowej, osadach dennych (frakcja poniżej 0,20 mm) oraz w tkankach miękkich (całe ciało) i muszlach Anodonta anatina. Analizowano 20 próbek tkanek miękkich i 12 próbek muszli Anodonta anatina oraz po 20 próbek wody powierzchniowej i osadów dennych. Na każdym stanowisku analizowano próbki Anodonta anatina obejmujące co najmniej kilkanaście okazów o różnych rozmiarach (tzw. próbki uśrednione). Oznaczenia Cu, Zn, Pb, Co, Cd dokonano techniką ICP-AES, a Hg oznaczono techniką CV-AES. Przy zastosowaniu Anodonta anatina, jako organizmu wskaźnikowego, rejestruje się zmiany poziomów stężeń metali ciężkich w wodzie powierzchniowej na podstawie analizy tkanek miękkich i muszli (Cu i Zn), analizy muszli (Pb i Hg) oraz analizy tkanek (Hg). Z sześciu badanych metali nie kontroluje się tylko zmian Co. Z kolei zmiany koncentracji metali w osadach można kontrolować, wykorzystując tkanki miękkie i muszle (Zn i Hg), tylko tkanki (Cu, Pb i Cd) i tylko muszle (Co).
EN
The aim of the present article was the determination to what extent soft tissues and shells of the Anodonta anatina (Anodonta cygnea piscinalis NILSSON 1823; Anodonta piscinalis NILSSON 1823) reflect the changes Cu, Zn, Pb, Co, Cd and Hg in superficial water and bottom sediments (fraction below 0.20 mm) of the Odra River estuary. The material for laboratory investigations was taken in years 1999 and 2000 of the Odra River estuary (19 research points) and from Lake Miedwie (one research point). The concentrations of metals were marked at every research point in superficial water, bottom sediments and in soft tissues (whole body) and shells of the Anodonta anatina. 20 samples of soft tissues, 12 samples of the shells of the Anodonta anatina and 20 the samples of superficial water and bottom sediments were analysed. Samples of the Anodonta anatina (averaged samples) were analysed at every research point consisting more than ten specimens of various sizes. Quantitative determination Cu, Zn, Pb, Co, Cd was executed with the technique ICP-AES and Hg was marked with the technique CV-AES. The changes of the levels of the concentrations of heavy metals in superficial water were correlated with the results of the analysis of soft tissues and shells (Cu and Zn), the analysis of shells (Pb and Hg) and the analysis of soft tissues (Hg). Only changes of the Co did not show appropriate correlation. The soft tissues and shells (Zn and Hg), only soft tissues (Cu, Pb and Co) and only shells (Co) can reflect the changes of concentration of metals in bottom sediments.
EN
The shells of Lymnaea peregra and L.stagnalis were collected from a fishing pond in Kłemby near Nowogard (NW Poland), and those of Dreissena polymorpha came from the nearby Odra River estuary (Roztoka Odrzańska). The latter site had much higher concentrations of heavy metals, both in water and in bottom sediments. The study aimed at finding correlations between the concentrations of heavy metals and organic carbon and the shell size. In shells of freshwater snail Lymnaea peregra three second degree polynominal correlations were confirmed at the 0.05 significance level of between concentrations Co (positive), Corg. (negative) and Cd and height of shells. In the other three cases (Cu, Pb, Zn) there was no correlation significant at the 0.10 level. In shells of Lymnaea stagnalis three parameters shown significant (at the 0.05 level) correlation with shell size: concentrations of Zn (negative), Co (negative) and Corg. (positive). The other three (Cu, Pb, Cd) were insignificant even at the 0.10 level. In shells of a bivalve, zebra mussel Dreissena polymorpha, concentrations of four element shown significant (p=0.05) correlation with shell length: Pb (negative), Zn, As and Hg (all positive). Concentrations of Sr and Co were positively correlated and concentrations of Cd and Corg. Negatively correlated with shell size of this species at 0.10 significance level. Both in the case of snails and zebra mussels, no significant correlation was observed between their size and Cu concentrations. The results indicate that there the concentrations of heavy metals and Corg are indeed size-dependent, and the correlations differ among studied molluscs. Further research is necessary to establish standard procedures for measurements of these parameters for use in monitoring studies: whether the concentrations in shells of indicator species should be analysed in specimens of standard size or standard age to allow for comparisons of measurments taken in different sampling sites or habitats.
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