Application of Headspace Solid-Phase Microextraction for Determination of Chloro-Organic Compounds in Sewage Samples

Solid phase microextraction (SPME) has been optimized and applied to the determination of the volatile halogenated compounds (VHCs) and semi-volatile halogenated compounds (SVHCs). Three types of SPME fiber coated with different stationary phases (PDMS–100 μm, CAR/PDMS-75 μm, PDMS/DVB–65 μm) were used to examine their extraction efficiencies for the compounds tested. Experimental parameters such as the selection of SPME coatings, extraction time, and addition of salts were studied. The carboxen-polydimethylsiloxane (CAR/PDMS) fiber appears to be the most suitable for the determination of VHCs. Analytical parameters such as linearity, limit of detection, and precision were also evaluated. Application of ECD detector for the determination of VHCs and SVHCs allows their determination on the low concentration level, ranging from 0.005 to 0.8 μg/L−1. The HS-SPME-GC/ECD procedure gave good analytical precision expressed as relative standard deviation (RSD) (ranged from 5.08% to 8.07%) for a concentration level of 5 μg/L−1 and good linearity (r2 > 0.98) in a wide calibration range. The applied HS-SPME-GC/ECD method was found to be a quick and effective technique for the determination of microtrace amounts of volatile and semi-volatile halogenated compounds in samples containing high amounts of various organic compounds

La conservazione preventiva del patrimonio librario come possibile alternativa al restauro tradizionale

The present paper focuses on the close relation between library collections and their preservation environment, aiming, in particular, at highlighting the importance of promoting and sustaining the monitoring. The paper proposes some simple and ready-to-use technologies – smart monitoring – to prevent future damages

Genetic variation for heterotrophic growth in maize in relation to temperature

The investigation was conducted in the frame of early maize (Zea mays L) adaptation to northern Europe climatic conditions. In these countries, tolerance to low temperature during the first stages of development is necessary to ensure a good yield. We were therefore interested in seedling behaviour during heterotrophic growth. We observed rates of radicle elongation of 13 genotypes (inbred lines, hybrids or populations) at 18 controlled temperatures from 6 to 40 °C. One group of genotypes was used to determine endosperm influence. Results of non-linear analysis were in favour of the existence of genetic variation, even if seed effects were not clearly determined. This variation was found to be due to differences in temperature sensitivity or seedling vigour. It was particularly evident for elongation rates (from 0 to 0.2 mm/s in a cold environment, and for optimum temperature between 27 and 30 °C).Variabilité génétique pour la croissance hétérotrophe chez le maïs en relation avec la température. Cette étude se situe dans le cadre de l'adaptation des maïs (Zea mays L) précoces aux conditions climatiques du Nord de l'Europe. Dans ces régions, la tolérance aux basses températures pendant les premiers stades de développement est nécessaire pour assurer un bon rendement. Nous nous sommes intéressés au comportement de plantules pendant la phase de croissance hétérotrophe. Nous avons observé la vitesse d'élongation de la radicule de 13 génotypes (lignées, hybrides ou populations) à 18 températures comprises entre 6 et 40 °C (fig 4). Un groupe de génotypes a permis d'étudier l'influence de la qualité de la semence. Les résultats de l'analyse non linéaire permettent de conclure à l'existence d'une variabilité génétique, même si l'effet du support-semence n'a pas pu être précisément défini. Cette variabilité trouve son origine dans des différences de sensibilité aux températures ou dans des différences de niveaux de vigueur. Elle se traduit en particulier par des variations de la vitesse de croissance à basse température entre 0 et 0,2 mm/s (tableau III) ou des déplacements de l'optimum thermique entre 27 et 30 °C (tableau II)

Heat units requirements of maize inbred lines for pollen shedding and silking: results of the european FAO network

International audienc

Les unités expérimentales viti-vinicoles et leurs vins

National audienc