Die Bedeutung der Zeit

The consideration of time in environmental research allows new insights into the fundamentals of environmental research and new pathways for perceiving and answering questions which might arise in environmental research. In order to take this all into account, one must realize that ecological systems have a history and that both the spatial aspects and the chronological expansion of these systems must be taken into consideration. Considering temporalities, rhythms and time scales as well as their interdependencies in environmental research and environmental protection enables us to obtain a better understanding. The significance of relationships and functions in ecological systems can be perceived better as well. The impact of pollutants as well as the outcome of human actions in ecology, and in economics and politics, is consequently mandatory for not only a spatial, but also for the involved temporal scales.     

Kinetik und Mechanismen beim photochemischen Abbau von Fluorphenolen

The results of a study of the photolytic degradation of mono- and difluorophenols as a function of oxidation agent and temperature are reported. The effects of the position of fluorine are discussed. Fluorinated aromatic compounds have been mineralized to CO₂, fluoride, acetate and formate by irradiation (l=254nm) over various intermediate steps. The degradation of fluorophenols apparently followed first-order kinetics. A proposed degradation pathway for the photolytic oxidation of fluorophenols is presented. A complete mineralization as generally proposed in the literature cannot be supported by our results.     

Evaluation of industrial waste black cumin (Nigella Sativa) for biohydrogen production without pretreatment

Environment, Development and Sustainability - The depletion of fossil fuels and the fact that fossil fuels pollute the environment accelerated the trend toward environmentally friendly energy...     

Oily substances from gastral intersegmental glands of the antPachycondyla tridenta (Ponerinae): Lack of pheromone function in tandem running and antibiotic effects but further evidence for lubricative function

Summary Gas chromatographic analyses of volatizable material from gaster intersegmental complex glands ofP. tridentata revealed the presence of linoleic acid, palmitic acid, methyl oleate, and several long-chain hydrocarbons as major constituents, which form an oily fluid mixture. The nest relocation communication ofP. tridentata is tandem running. Tandem following is mediated by pheromones as demonstrated by dummy experiments with isolated gasters and thoraces and with glass balls. The secretions of all gaster complex glands, as well as hind gut contents and metapleural gland secretions, were unable to evoke tandem following. Morphology and position of the glands, lack of pheromonal function, oily properties, low volatility, and lack of antibiotic effects of these secretions strongly suggest a function as lubricants for the ants' gastral segments.     

Tiefsee-Bergbau auf Manganknollen vor dem Hintergrund globaler Versorgungs- und Umwelt-Probleme

Ich danke C. Kaubisch (Göttingen) herzlich für die graphische Ausf ührung der Abb., Prof. H. Thiel (Hamburg) besonders für kritische Diskussionen, Durchsicht des Manuskriptes und wertvolle Anregungen. Ebenso danke ich Dr. M. Sturm (EAWAG/ETH Zürich) für Kritik und Anregungen.