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We report on exploratory calculations of triply differential cross sections for (e, 2e) reactions on atomic clusters carried out in the first order Born approximation. Using a jellium model description of the target, reasonable agreement with recent experimental data for C60ionization obtained by Vos et al. (Phys. Rev. B 56, 1309 (1996)) is obtained.

2,4,6‐Trichlorophenol (2,4,6‐TCP) was extensively used in the past as a component of various pesticide formulations as well as a wood preservative and, therefore, is ubiquitously present in the environment. It is also formed during the disinfection of drinking water sources or during wastewater treatment and is frequently detected in sewage sludges. Under anaerobic conditions, reductive dehalogenation is the most promising biological process for its detoxification. Here, an anaerobic, 2,4,6‐TCP ortho‐dehalogenating mixed culture is described, which was originally enriched from a Saale river sediment. In order to be able to analyze the capacity of this dechlorination process for the removal of 2,4,6‐TCP, a steady‐state continuous culture was grown over a period of 270 days under an N2‐CO2(80:20) gas atmosphere in a chemostat using formate as an electron donor and 2,4,6‐trichlorophenol (2,4,6‐TCP) as an electron acceptor. 2,4,6‐TCP was dechlorinated via 2,4‐dichlorophenol (2,4‐DCP) to 4‐chlorophenol (4‐CP) liberating two chlorine atoms per molecule of 2,4,6‐TCP as chloride. Per mol of chloride, 2.2 mol of formate were consumed and 0.17 mol of acetate formed. When yeast extract (0.01 %) was omitted from the cultivation medium, 2,4‐DCP accumulated in the chemostat, suggesting that the components in the yeast extract were essential for reductive dechlorination. A second fermentation was performed over a period of 130 days in the absence of CO2in the gas atmosphere and of carbonate in the cultivation medium, resulting in a slightly higher specific dechlorination rate, a higher requirement for formate, and a lower protein yield, indicating that formate was used as a sole carbon source for growth. The dilution rate (D) was continuously increased, leading to an increase of the dechlorination velocity up to 400 μmol Cl–/L h, a maximum specific dechlorination rate of 0.48 μmol Cl–/L min (mg protein) and a yield of 5.1 g protein/(mol Cl–released). The microbial community structure of the mixed culture was investigated by amplified ribosomal DNA restriction analysis (ARDRA), sequencing, and hybridization with species specific oligonucleotide probes. The dechlorinating bacterium Desulfitobacterium hafniensewas found to be a dominant member of the mixed chemostat culture. Further members of the chemostat culture were detected by comparative analysis of the restriction patterns and sequencing and identified as bacteria most closely related to strains of Sedimentibacter, Clostridium propionicum,and Pseudomonas aeruginosa.

Information and communication technology (ICT) is changing communication and interaction in private and business behavior. This paper analyses and discusses these changes. We observe that ICT facilitates the dissemination of information in unprecedented quantity and speed. As a consequence, the means for processing this amount of information have to improve. Innovative technologies and organizations gain importance within business contexts that demand more flexibility and substantial efficiency gains. This leads to a new industrialization, the industrialization of information processing (Schmid 1998; 1999). We employ the business media approach to explore and model the forthcoming platforms, organizations and business models. This approach comprises: (1) a general concept of media; (2) a Business Media (BM) framework, suggesting a generic business media architecture; (3) an analysis model providing, in accordance with the Media Model and the BM framework, a guideline to design-specific reference models. According to the business media approach, we analyse and design the role and business model of a logistic service provider (LSP). The case study 'IBM TransConnect' validates, how a platform changes the roles and business model of LSPs.

A number of alkyl and acyl derivatives of 4-dihydro-4-deoxy-4(R)-amino spectinomycin were tested against various Escherichia coli strains, possessing different susceptibilities to spectinomycin. The influence of the lipophilicity and the length of the side chain substituents of the derivatives was compared to both minimal inhibitory concentration values and stability to adenyltransferase. Derivatives with a chain length of more than 10 carbon atoms demonstrated a significantly higher activity against all investigated strains, whether susceptible or resistant. The same inhibitory effect was achieved with short-chain aminoacyl derivatives only against susceptible strains. Other short-chain derivatives possessed no advantage to spectinomycin. A 10-fold decrease in the affinity for adenyltransferase was achieved in compounds with a high lipophilicity (log P), i.e., in aliphatic substituted derivatives with a log P greater than 4 and in benzoyl-substituted derivatives with a log P greater than 2. Derivatives with branched alkyl chains and long side chains displayed a different mode of action than spectinomycin. They possessed strong activity against strains with an altered ribosomal binding site and a decreased influence of pH on antimicrobial activity.

The cephalosporins (I) are acylated with the amino pyrimidines (II) to produce the compounds (III).

The dinuclear complexes (I) and (II) are studied by cyclic voltammetry in DMF.