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Synthesis and mineralogical characteristics of hydroxylapatite-hydroxylpyromorphite solid solution series Ca5(PO4)3OH – Pb5(PO4)3OH

100%

Motyka J. , Oknińska J. , Manecki M.

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tom Vol. 41, no. 1

112--113

EN

Lead is a widespread environmental contaminant toxic to living organisms. Soils and wastes contaminated with Pb are found in both rural and urban settings. Uptake of Pb from waste, soil or water by phosphate compounds, particularly hydroxylapatite, has been proved as effective remediation strategy (Xu & Schwartz 1994). The technology arises from the low solubility of lead apatites and from their rapid precipitation reactions. The structure of the apatite group minerals can be described by the general formula A5(BO4)3C, where positions A, B, C can be substituted by e.g. A: Ca, Pb, Sr, Ba; B: P, As, V; C: Cl, OH, F, Br, I. Apatites are very tolerant to structural distortion resulting from chemical substitution in cationic and anionic positions and consequently they are remarkably diverse in composition. Thanks to this potential for extensive solid solutions in the system, the lead apatites precipitating in the environment are not pure end members but rather Pb-Ca solid solutions. A complete solid solution between hydroxylapatite (HAP) and hydroxylpyromorphite (HPY) was determined before (Bigi et al. 1991, Hadrich et al. 2001). The results, however, are still fragmentary. The objective of the project is systematic characterization (crystal structure and infrared and Raman vibrational properties) of synthetic analogs of the minerals from HAP-HPY solid solution series. This will allow clarifying the controversies related to the change of properties towards substitution of lead for calcium. Well characterized products of the synthesis will be used in further thermodynamic study of solubility changes with substitution, which was never determined before. It is assumed t hat t he properties vary in systematic way with Pb substitution for Ca. An effective wet method of synthesis of Ca-Pb apatites was developed. A crystalline, homogeneous precipitates with stoichiometric composition were produced. Six phases of HAP-HPY solid solution series were prepared by dropwise mixing of a solution containing calcium and/or lead ions and a phosphate solution at room temperature. During the synthesis pH of 8.5 was maintained using NH4OH. Precipitates were washed, air dried and characterized by scanning electron microscopy (SEM) with the energy dispersive spectroscopy detector (EDS), powder X-ray diffraction, infrared spectroscopy (FTIR) and Raman spectroscopy. All synthetic products obtained in the experiments form hexagonal needles less than 0.1 μm long. Elemental composition of six product phases is consistent with the objectives of the experiment. X-ray diffraction patterns reveal a shift toward lower angles 2θ for phases with higher lead contents. This indicates an enlargement of the lattice constants. The variation of parameters, however, is not linear (does not follow the Vegards law). Particularly the cell parameter c changes more for phases reach in lead. These results are in agreement with those reported previously (Bigi et al. 1991, Hadrich et al. 2001). A shift of band position is also observed in both FTIR and Raman spectra. All the bands shift towards lower wave number with increasing Pb content. In most cases the shift is not linear exhibiting two trends similar to those of crystal lattice parameters. This may indicate that the vibrational properties of the phases in the series depend stronger on the bond length than on the atomic mass of substituting elements.

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Metavolcanics of Nordenskiold Land from SW Svalbard as an example of New Ocean Crust

88%

Gołuchowska K. , Barker A. K. , Manecki M. , Majka J. , Czerny J.

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tom Vol. 38, no. 4

473

EN

This study concerns late Neoproterozoic metavolcanics from southwestern Svalbard in an investigation to trace the evolution of oceans plate rifting. A number of outcrops of these rocks are connected with the regional Torellian unconformity, which is associated with a Late Neoproterozoic orogenesis event - post 640 Ma. This unconformity divides the younger metasediments of the Sofiebogen Group from older metasedimentary sequence of the Deilegga Group. Samples have been collected from Nordenskiold Land belonging to the Sofiebogen Group, which is situated between Bellsund and Isfjorden, to the north of Wedel Jarlsberg Land. Field observation reveals that these metavolcanics very often occur as a pillow lavas and lavas. They contain mineral assemblages typical for greenschist facies metamorphism such as: actinolite, chlorite, epidote, albite, but some of them contain garnets and glaucophane, which is typical for blueschist facies conditions. Based on a total alkali silica diagram they are classified as tholeitic basalts. Spider diagram shows patterns similar to MORB, where the REE are flat. The LILE except Sr are depleted, but this depletion is caused probably by metamorphism. However, the metavolcanics of Nordenskiold Land are also relative depleted in HFSE (Th/Yb = 0.2-0.31 and Nb/Yb = 2.9-4.4) and LREE (Lan/Smn = 1.0-1.5). Trace elements like Nd, Th, Yb and La show trends that could be associated with fractional crystallization. The geochemical character of metavolcanics from Nordenskiold Land, as well as, their forms (pillow lavas) suggests that they created beneath the sea level, as new ocean crust.

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Pochodzenie i zagrożenia siarkowodorem i wysokociśnieniowym gazem ziemnym w złożu kopalń rud miedzi Polkowice-Sieroszowice i Rudna – wstępne badania izotopowe i mineralogiczne

76%

Kotarba M. J. , Bilkiewicz E. , Manecki M. , Pawlik W. , Ciesielczyk A. , Selerowicz T.

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tom nr 469

9--33

PL

Wyniki badań składu cząsteczkowego i izotopowego (13C/12C w CH4, C2H6, C3H8, iC4H10, nC4H10 i CO2, 2H/1H w CH4 i 15N/14N w N2) dwóch próbek gazu ziemnego występującego w utworach wapienia cechsztyńskiego (Ca1) kopalni Rudna porównano z gazem ziemnym akumulowanym w utworach karbonu, czerwonego spągowca i wapienia cechsztyńskiego (Ca1) monokliny przedsudeckiej oraz gazu wytworzonego podczas pirolizy wodnej z kopalnej materii organicznej utworów dolomitu głównego (Ca2). Badany gaz ziemny charakteryzuje się normalnym składem izotopowym w układzie metan–etan–propan, co świadczy o tym, że powstał w jednej fazie generowania z tej samej skały macierzystej, zawierającej kerogen mieszanego typu II/III, prawdopodobnie w obrębie utworów karbońskich. Na podstawie badań mineralogicznych i izotopowych 13C/12C 12 próbek węglanowych i 34S/35S 14 próbek siarczanowych, pobranych w strefie głębokości eksploatacji rud miedzi od 900 do ok. 1200 m ZG Polkowice-Sieroszowice i Rudna w zakresie współczesnych temperatur od 35 do 45°C, wykazano, że w dwóch próbkach węglanów i w dwóch próbkach siarczanów pobranych z jednego rdzenia zachodzą procesy mikrobialnej redukcji anhydrytu dolnego (Ad1) cyklu PZ1 prowadzące do powstawania siarkowodoru.

EN

Composition of natural gas from the Zechstein Limestone (Ca1) strata of Rudna mine has been compared with the natural gas from Carboniferous, Rotliegend strata of the Fore-Sudetic Monocline and with gas generated from the organic matter of the Main Dolomite during hydrous pyrolysis experiments. The gas from Rudna mine is characterized by the normal methane–ethane–propane isotopic system which indicates formation in one stage from a single source rock probably of the Carboniferous age containing kerogen of mixed II/III type. Generation of the hydrogen sulphide resulted from the microbial sulphate reduction processes of the basal anhydrite has been proven by mineralogical and isotopic 13C/12C analyses of 12 carbonate and 34S/35S analyses of 14 sulphate samples. These samples were collected in the mine at the depth of about 900–1200 m at temperature range of 35–45°C and two samples of carbonates were taken from one core.