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[en] The energy question is vital, complex and worldwide at the same time. Each day, our Earth offers to us an abundant, clean and renewable energy, but strangely, we prefer to use fossil, fissile, non-renewable and polluting energy sources. Starting from this fact, this book proposes a complete reorientation of the French energy policy. The author presents first the present day situation and its drawbacks: wasting, concentration of efforts on nuclear power generation, non-development of renewable energy sources and of energy conservation, development behind the time in several domains. He demonstrates that the real energy dependence ratio of France is in fact of 72%, that the French energy system is fragile both on its technical and geopolitical aspects, and finally, that France is prisoner of its past political and technical choices. After this detailed and well documented analysis, the author pleads for a set of consistent political, institutional and technical solutions: sharing competences and decision powers between the government and the local organizations, reducing the use of fossil fuels, saving energy at all levels, selecting the proper energy source according to its use in order to improve its efficiency, developing renewable energy sources as a complement to centralized productions by a valorization of local natural resources, and giving citizens a responsibility as decision-makers. All those realistic proposals are based on the presentation of successful experiments already carried out in some French regions. Only the implementation of these solutions would allow to reach the goal of dividing by a factor 4 our greenhouse gas emissions and to ensure the geopolitical energy independence of France. (J.S.)
[en] This document provides information on the geothermal energy. It presents the different types of geothermal deposits (very low, low and medium energy geothermal energy), the french deposits and the heat production. The electric power production from the geothermal energy is also discussed with the example of Soultz-sous-Forets. The last part deals with the heat pumps. (A.L.B.)
[en] Very low rates of biodegradation were observed for an organic pollutant in lake water and sediments. - A single tertiary isomer which is believed to be one of the major branched isomers of the isomeric nonylphenol was synthesized for use in investigations on its metabolism and estrogenicity in aquatic organisms. The physico-chemical properties of the isomer were determined to enable the prediction of its behaviour in aquatic environments. From laboratory investigations on its dissipation and distribution in lake water, which are reported in this paper, it was found that it had a half-life of dissipation of 38.1 days and 20.1 days in an open lake water and in an open lake water/ sediment system, respectively, and to be rapidly partitioned in to sediment giving a high concentration factor of 1.76 after 28 days with an initial dose concentration of 2.52 ppm. The main dissipation route was found to occur through volatilization and co-distillation. The isomer was, however, found to be resistant to biodegradation in both the lake water and sediment, showing only a slight 9% loss (after 56 days) and 4.2% loss (after 28 days), of the 14C-residues in lake water and lake water/sediment systems, respectively, by microbial activity. Transformation to other more polar metabolites possibly by hydroxylation was also found to be minimal in both lake water and sediment samples after 14 days by HPLC analysis. After 7 days, only 2.25 and 7.4% transformation to a more polar metabolite was detected in lake water and sediment samples, respectively
[en] The branched isomers of p-nonylphenol (NP) are perceived to be more resistant to biodegradation in aquatic environments as well as to have more estrogen-like toxicity than the straight chain isomers. By use of GC-MS, some of them have been identified and found to exist in higher concentrations in the isomeric compound mixture than the straight chain isomers. The investigations of the distribution and metabolism of these branched isomers in aquatic organisms are therefore considered to be important in understanding the mechanisms of toxicity of NP. A single tertiary isomer of NP, 4(3'-,6'-dimethyl-3'-heptyl)-phenol, was synthesized in the laboratory and used in in vivo studies of its organ distribution and metabolism in Lymnaea stagnalis L., following a constant exposure of the organisms to 14C-NP isomer in water over a period of 8 days at an average exposure concentration of 105 ppb (range: 93-116 ppb). The results obtained clearly showed the distribution and bioconcentration of the isomer residues in various internal organs of Lymnaea after uptake in water and food. Analysis of the extracts of the organ tissues and faeces by HPLC and GC-MS after digestion with Pankreatin/β-glucuronidase and nitric acid, respectively, showed that the isomer was metabolized by conjugation to glucuronic acid and hydroxylation to a catechol. The findings from these studies and their implications in the biotransformation and estrogenicity of NP in Lymnaea stagnalis L. are further discussed in detail in this paper
[en] Concentrations of polychlorinated dibenzodioxins (PCDD), polychlorinated dibenzofurans (PCDF), chlorobenzenes, chlorophenols, polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) were measured in the stack gas of a hazardous waste incinerator. Toxicity equivalents (I-TE) were calculated according to the international toxicity equivalency factor scheme. I-TE were significantly correlated with chlorobenzenes and PCB. These classes of compounds can therefore be used as indicator parameters from which I-TE values may be estimated. The most accurate estimates were made using pentachlorobenzene or heptachlorobiphenyl. (orig.)
[de]Im Reingas einer Sondermuellverbrennungsanlage wurden polychlorierte Dibenzodioxine (PCDD), polychlorierte Dibenzofurane (PCDF), Chlorbenzole, Chlorphenole, polychlorierte Biphenyle (PCB und polycyclische aromatische Kohlenwasserstoffe (PAH) gemessen und die auf die Toxizitaet von 2,3,7,8-Tetrachlordibenzodioxin bezogenen Toxizitaetsaequivalente (I-TE) berechnet. I-TE korrelierte hochsignifikant mit Chlorbenzolen und PCB. Diese Verbindungen koennen daher als Leitparameter verwendet werden, anhand derer die I-TE-Werte abgeschaetzt werden koennen. Als beste Leitparameter fuer die I-TE-Werte im Reingas eigneten sich Pentachlorbenzol und Heptachlorbiphenyl. (orig.)
[en] The traditional course content of chemistry classes must change to achieve better awareness of the important issues of sustainability in chemistry within the next generation of professional chemists. To provide the necessary material for the organic chemistry teaching lab course, which is part of almost all study programs in chemistry, material was developed and collected (http://www.oc-praktikum.de/en) that allows students and teachers to assess reactions beyond the experimental set up, reaction mechanism and chemical yield. Additional parameters like atom economy of chemical transformations, energy efficiency, and questions of waste, renewable feed stocks, toxicity and ecotoxicity, as well as the safety measures for the chemicals used are discussed. (author)
[en] A set of brief articles outlines the importance of energy networks of all kinds for the future of energy conservation. Thus, all networks (communication, data, production command and control) will have a role to play to make all energy networks (electricity, gas, heat, cold, water, sewage, telecommunications) communicate with each other, and a new consumption/production model will have to be developed for each territory by taking into account its capacities to improve energy efficiency and valorize renewable energies. The authors also propose a historical perspective of network development and of their trend to become interconnected and complementary, comment the governance issue in terms of concession, evoke the supply of public networks with biogas (legal framework under development), discuss the value of the project of development of smart grids, suggest that a better electricity demand management could be an efficient alternative to grid development, comment the context and implications of the European directive Linky, outline that heat networks will contribute to the reduction of the environmental impact of buildings, evoke the issue of cold water networks and their impact on air conditioning, present the original heat network which is about to be built in Saint-Brieuc, etc.
[en] Highlights: • Photoisomerization of vinyl-substituted stilbenes (0, 1, 2, 3, 4). • Extinction spectra of 0, 1, 2, 3, 4. • Ultrafast (4) or slow (3) twist to perpendicular molecular conformation P. • Long-lived (∼100 ps) perpendicular conformation P. • Zwitterionic character of P, its dipole moment is of ∼3D. Photoisomerization of 1,1′-di-tert-butylstilbene (3) and 1,1′-dicyanostilbene (4) is monitored with stationary and broadband transient absorption spectroscopy. The electron affinity of the substituents correlates with the shift of the absorption band. The weak extinction of 3 complicates data interpretation, but comparison with earlier measured 1,1′-dimethylstilbene (1) and 1,1′-diethylstilbene (2) helps to assign transient spectra and relaxation paths. For 3 a long-lived perpendicular state P is observed with lifetime τP = 134 ps in acetonitrile. For 4 τP = 2.1 ps in acetonitrile and 27 ps in n-hexane, the difference indicating a substantial dipole moment (∼3D) of the P state.