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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.

International audience; Soil characteristics of a wild tropical forest from Cote d`Ivoire and composition of directly extractable soil lipid fraction were investigated. This study was undertaken with the aim to establish soil characteristics, structures and origin of directly extractable lipids components as the first step in understanding diagenesis processes in soil of Cote d`Ivoire. Studies required the use of particle size fractionation and spectrometric (GC/MS) methods. Main characteristics of the soil are the following: neutral pH (6.7), absence of carbonates, sandy texture (88% of sand consisting of silica) and low total organic matter content (4% including 644 mg kg-1 of extractable lipid) localized in fine fraction (90%). Directly extractable lipid fraction is composed by aliphatic series of alkanes, normal alcohols, fatty acids and triterpenes. The fatty acids, by their composition and the prominence of even carbon chains, could originate from higher plants and highlight a strong microbial activity. Long normal and odd carbon chains compose exclusively alkanes while long even carbon chains form alcohols. Such a distribution underlines the double origin (fungi and/or microbial) of these compounds. Few triterpenoids, found in directly extractable lipids, are formed exclusively by cholestene and derivatives. Such a structure indicates either the reductive character of this soil, or the triterpenes vegetal origin.

Single event transients (SET) occur when an energetic subatomic particle strikes a combinational logic element. The charge deposited by the particle causes a transient voltage disturbance, which can propagate to a storage element and be latched, resulting in single event upset (SEU). The logic design style, storage element behavior, and system timing requirements greatly impact the probability that an SET will cause an SEU. These effects are explored through circuit simulations and heavy ion testing of prototype devices.

International audience; In order to determine the ability of soil lipids to migrate through natural leaching by rain water, litter and soil A1 horizon of a podzol soil were sampled. Samples were placed in glass columns and experimentally leached with distilled water slowly delivered by a peristaltic pump. Soluble lipids were extracted from leachate with chloroform. Hydrocarbon, fatty alcohol and fatty acid fractions were isolated from soluble lipids by column chromatography after saponification and methylation. The soluble components of each family were determined by GC and GC-MS then compared to soil lipids previously analysed. The results showed that the water soluble fraction of lipids was very low and mainly released by the litter sample. A decoupling of hydrocarbons, fatty alcohols and fatty acids was observed in the dissolved and in the total lipid phases, the components of the soluble phase being chiefly of microbial origin and those of the total phase essentially of plant origin.

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.