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1

Sugars in environmental samples and sedimentary rocks : effectiveness in derivatization for GC-MS analysis

Smolarek-Lach Justyna, Goryl Magdalena, Marynowski Leszek

Geological Quarterly

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2021

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Vol. 65, No. 3

art. no. 40

EN

Saccharides (sugars), common constituents of the bio- and geosphere, are useful in determining the source of organic matter (OM) in aerosols and early diagenetic phases. Due to the chemical properties and great diversity of sugars in nature, a wide range of techniques is used for the isolation and quantification of saccharides. Here, gas chromatography-mass spectrometry analysis, preceded by derivatization with N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), was undertaken. The effectiveness of this derivatization was demonstrated for soils, aerosols, fungi, and individual sugar standards. The efficacy of BSTFA derivatization for individual sugar standards and, similarly, for samples of sugars in winter and summer aerosols was adequate. In fungi and soil samples, the MSTFA reagent was much more effective. Different mono- and disaccharides were identified in biological samples and sedimentary rocks, showing not only the great diversity of these compounds but also the specificity of their origin in recent and ancient OM. Greater variation in the occurrence of sugars in soils compared to rocks may suggest differences in the stability of some saccharides at an early stage of diagenetic transformation. Comparison of the occurrence of certain sugars in biological samples and sedimentary rocks sheds new light on the origin and preservation of these biomolecules.

2

Petrological studies of low temperature oxidation of lignites

Markova K., Stefanova Y., Boneva M.

Polish Geological Institute Special Papers

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2002

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Vol. 7

159-168

EN

The low temperature oxidation processes which has taken place in lignites and their lithotypes (xylain, humovitrain, semifusain, fusain and liptain) from the East Maritza basin have been studied. The changes occurring in the coals/lithotypes composition and structure during their oxidation have been followed by examining reflectance, microhardness, proximate, ultimate, functional, and increment analyses. The main kinetic parameters such as duration of the induction period, maximum and stationary rates and the apparent activation energies were evaluated. The complex investigation provides a detailed information for the behaviour of low rank coals and their lithotypes towards the action of atmospheric oxygen. Thus some suggestions concerning the mechanisms of their oxidation reactions can be made. The individual way of the genesis of each one of the lithotypes and the resulting physicochemical structure predetermine the basic mechanism of these reactions. However, it has been found that in spite of the similar genesis the lithotypes differ in the mechanism of their oxidation. For xylain the oxidation takes place mainly via aryl radicals yielding tertiary peroxide and carbonyl groups. The oxidation of humovitrain is characterised by the dominant participation of aroxyl radicals resulting in accumulation of primary hydroperoxide and phenol groups. The oxidation of semifusain leads mainly to the formation of molecular products. The oxidation of fusain is found to be essentially different from that of other lithotypes. It is characterised by the formation of carbonyl groups attached to biphenyl aromatic structures. The peculiar petrographic composition and structure of liptain account for the occurrence of oxidation processes accompanied by destruction reactions at relatively lower temperatures. It has been established that the intensity of the oxidation processes varies from one lithotype to an other. Xylain and humovitrain oxidise most intensively. The intensity drops off from the first towards the second member of the corresponding genetic series, i.e. from xylain to humovitrain and from semifusain to fusain.

3

Wiek węgla brunatnego na tle pozycji geologicznej badanych próbek (KWB "Bełchatów")

Szynkiewicz A.

Przegląd Geologiczny

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2000

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Vol. 48, nr 11

1038-1044

PL

Flory najniższego pokładu węgla w kompleksie utworów podwęglowych (PW), złoża węgla brunatnego "Bełchatów", odpowiadają wiekowo florom starszej części eggenburgu. Flory z górnej części pokładu głównego (PG), nie są młodsze od ottnangu. Zbiorowiska roślinne pokładów węgla C i B są zbliżone do flor karpatu. Szczątki flor kopalnych z warstw najwyższej części kompleksu I-W oraz z warstw kompleksu I-P pochodzą z młodszego neogenu. Flory kompleksu I-P są podobne do flor pannonu Europy Środkowej. Fauny kopalne zespołu Bel. C (zebrane z warstw wapieni jeziornych w górnej części głównego pokładu węgla brunatnego), można porównywać z kopalnymifaunami zony MN4-5, datowanymi na późny ottnang-karpat-wczesny baden. Fauny zespołu Bel. B (zebrane miedzy pokładami węgla A i B), można porównywać z faunami zony MN5, datowanymi na wczesny baden. Fauny kopalne zespołu Bel. A (znalezione w utworach kompleku I-W), można porównywać z faunami żony MN 8-9, datowanymi na późny sarmat-wczesny pannon. Paratonstein (tonstein), występujący nad pokładem głównym węgla (PG), powstał ok. 18,1+1,7 My B.P., a paratonstein nad pokładem węgła A powstał ok. 16,5 š 1,3 My B.P. Pochodzą one z erupcji wulkanicznych w Karpatach wewnętrznych.

EN

Until now the question the age of the brown coal deposits from the Bełchatów lignite mine in Central Poland has remained measured. Based on paleobotanical data, the flora of the lowermost brown coal seam (in PW unit - sediments below the main coal seam) is Early Eggenburgian in age (Early Miocene). The flora from the upper part of the main lignite seam (PG) is not younger than the Ottnangian. The floral assemblage from the lignite seam C and B are similar to the floras of the Karpatian age. The rich fossil flora remains of mezofile forest assemblages have been found in the upper part of the unit I- Wand in the sediments of the unit I-P (both above the coal seam A). The fossil floras from the unit I-P are similar to the Pannonian floras of Middle Europe. The land mammals fossil fauna of assemblage Bel. C (from the upper part of the main lignite seam, PG), is similar to the fossil fauna assemblage of zone MN4-5 (Late Ottnangian-Karpatian-Early Badenian). The fossil fauna of assemblage Beł. B (found above the lignite seam B), can be compared to the fossil fauna assemblage of zone MN 5 (Early Badenian). The fossil fauna of assemblage Bel. A (from the unit I-W) can be compared with the fossilfauna assemblage of zone MN 8-9 (Late Sarmatian-Early Pannonian). The two paratonstein (tuffite, volcanic ash) layers have been dated using the fission tracks (FT) method, yielding ages of 18.1š 1. 7 My (sample above the main lignite seam PG) and 16.5+1.3 My (sample from above the lignite seam A)

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Preparation and characterisation of effective cheap adsorbent from lignites.

Finqueneisel G., Zimny T., Weber J.V., Vogt D.

Prace Naukowe Instytutu Chemii i Technologii Nafty i Węgla Politechniki Wrocławskiej. Konferencje

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1999

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Vol. 9, nr 56

305-311

EN

The adsorptive capacities of active carbons are essentially attributed to the internal surface area, porosity and surface reactivity. We described in this work chars obtained in one step in a rotary klin starting from two different lignites. In order to improve their adsorption capacities, a mild oxidation is proposed and evaluated. The objective of this work is to explore the feasibility of the use chars for adsorption in liquid and gaseous phases. The physical and the chemical effects of the oxidative treatment are discussed and connected to the modification of their adsorptive properties.