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[ES] Un año después de su apertura, la biblioteca ET ha logrado posicionarse dentro del entorno que le rodea como referencia cultural para el barrio, acercándose a conocer de primera mano las necesidades de sus vecinos y usuarios, para establecer un vínculo de comunicación, intercambio e integración, favoreciendo así la accesibilidad al conocimiento y la información, pero también el disfrute y el enriquecimiento social y colectivo.

A 29-step alkaline permanganate degradation of type III kerogen from Tyrolean (Hahntennjoch, Austria) oil shale was performed. A high yield of oxidation products was obtained (93.7 % relative to the original kerogen): 0.5 % neutrals and bases, 19.5 % ether-soluble acids and 58.9 % of precipitated (PA). A substantial amount of kerogen carbon (14.8 %) was oxidized into carbon dioxide. The organic residue remaining after the final oxidation step was 6.9 %. The PA components were further oxidized and the total yields relative to original PA were 1.0 % neutrals and bases and 59.0 % ether-soluble acids, the non-degraded residue being 29.3 %. Detailed quantitative and qualitative analysis of all oxidation products suggested the Tyrolean shale kerogen to be a heterogeneous macromolecular substance consisting of three types of structures differing in composition and susceptibility towards alkaline permanganate: the first, resistant, presumably composed of aromatic structures linked by resorcinol ethereal bonds; the second, combined in nature, the aliphatic part comprising methyl-substituents and short cross-links, both easily oxidized into CO2, water and low molecular weight acids and aromatic structures yielding aromatic diand tri-carboxylic acids as oxidation products; finally the third, composed of aliphatic cross-links and substituents, alicyclic (and/or heterocyclic) and some aromatic structures, bound into units moderately resistant towards oxidation. The overall yields of kerogen and PA oxidation products lead towards a balance between aromatic, alkane monoand dicarboxylic and alkanepolycarboxylic acids, suggesting a shift of the structure of Tyrolean shale kerogen from typical aromatic reference type III towards a heterogeneous aromatic-aliphaticalicyclic type structure. Stupnjevitom degradacijom kerogena tirolskog škriljca pomoću alkalnog permanganata dobijeni su visoki prinosi oksidacionih proizvoda. Dobijene nerastvorne kiseline naknadno su degradovane u 8 stupnjeva. Detaljna GC-MS analiza kiselina rastvornih u etru, dobijenih degradacijom kerogena, potom intermedijarnih nerastvornih kiselina, pokazala je da je kerogen tirolskog škriljca heterogena makromolekularna supstanca i da se sastoji iz tri tipa strukture, različitog sastava i različite osetljivosti na primenjeno oksidaciono sredstvo. Prvi tip je aromatične prirode sa rezorcinolnim etarskim umreženjem, otporan prema alkalnom permanganatu. Drugi se vrlo lako oksiduje, a sastoji se od aromatičnih struktura umreženih kratkim alifatičnim nizovima i sa većim udelom metil-supstituenata. Ovaj tip strukture je pri oksidaciji dao visok prinos SO2, alifatične kiseline malih molekulskih masa i aromatične dii trikarboksilne kiseline u visokom prinosu. Treći tip strukture je srednje osetljivosti na permanganat, a sastoji se od alicikličnih i/ili heterocikličnih i aromatičnih jezgara povezanih alifatičnim nizovima srednjih dužina. Kvantitativan odnos alifatičnih, aromatičnih i alkan-polikarboksilnih kiselina u oksidacionim proizvodima pokazao je da struktura kerogena tirolskog škriljca odstupa od tipskih, dominantno aromatičnih struktura tipa III, kojima pripada po svom H/C-O/C atomskom odnosu, i da je pomerena ka heterogenim, aromatično-alifatično-alicikličnim strukturama tipa II.

The infiltration and biodegradation of medium molecular weight hydrocarbons were studied in field and lysimeter experiments. An initial loading rate of 4 kg m(-2) of a gas-oil cut (nC12-nC21) was applied and the weathering of hydrocarbons was monitored by gravimetry and capillary gas-chromatography. The composition and vertical distribution of biogenic hydrocarbons were studied in control plots. After 3.5 years, 94% of the fossil hydrocarbons were removed from the field and 83% from the lysimeter. Microbial degradation was active in the 30 cm upper layer of the soil. The undegraded residue was composed of cyclic alkanes and aromatics. Hydrocarbons were shown to penetrate down to 60 cm in the field and 80 cm in the lysimeter. A preferential infiltration of light hydrocarbons was noted in the lysimeter, and a selective adsorption of the heaviest compounds on the organo-mineral matrix was demonstrated in the superficial layer of the soil. The potential for leaching of unmodified hydrocarbons towards the groundwater was slight, whereas the input of total organic carbon resulting from microbial activity could account for more than 1% of the initial carbon load.

A twenty-three step alkaline permanganate degradation of kerogen from Aleksinac (Yugoslavia) shale was carried out. A very high total yield of oxidation products was obtained (92.840/0 based on original kerogen). Detailed GC-MS analyses of ether-soluble acids, soluble products of further controlled permanganate degradation of precipitated acids and acids from aqueous solutions, served as basis for quantitative estimation of the participation of various types of products and for comparison with other kerogens based on similar criteria. The prevailing saturated long-chain aliphatic structure of oxidation products suggested a predominantly open-chain cross-linked aliphatic structure of Aleksinac shale kerogen, classified as type Ikerogen. Nevertheless, noticeable proportion of alkane-polycarboxylic and aromatic acids in the oxidation products indicated a larger share of alicyclic, heterocyclic, and aromatic structures in this kerogen. Oxidative degradation products were shown to enable more precise structural interpretation than the classification based on elemental analysis.