Cultures monoalgales: courte description et discussion d'une méthode permettant une observation à fort grossissement des cellules avant leur isolement à l'aide d'un emporte-pièce

A method allowing isolation of phytoplancton algae for unialgal cultures is briefly described. Advantages and limits of the method are discussed.     

Map of the geoidal ondulations in Italy and the cross section Como-Otranto

Summary Astronomic and geodetic values of all observations made in Italy from 1868 to the present days are used to draw the geoidal ondulations-map in Italy.The geoidal ondulation along a cross section from Como to Otranto (for 1160 km length) is then traced.     

“Industrial landscapes” as positive settings for tourism development in declining industrial cities —

This paper discusses the possibilities of revitalising declining industrial cities through tourism development. The main question is whether obsolete or declining industrial land uses in or around the city can be transformed into successful tourist land uses? Traditionally tourism and heavy industry have been considered contradictory land uses. The “industrial landscape” concept is developed here to show that undergiven circumstances, and because of the changing nature of modern industry, positive relations between the two could substantially contribute to the revitalisation process of the city. Two industrial zones within the city of Haifa, Israel, are used as a case study to show and evaluate how the concept can be implemented to bring about urban revitalisation through tourism development.     

Degradation of plastic carrier bags in the marine environment

There is considerable concern about the hazards that plastic debris presents to wildlife. Use of polymers that degrade more quickly than conventional plastics presents a possible solution to this problem. Here we investigate breakdown of two oxo-biodegradable plastics, compostable plastic and standard polyethylene in the marine environment. Tensile strength of all materials decreased during exposure, but at different rates. Compostable plastic disappeared from our test rig between 16 and 24 weeks whereas approximately 98% of the other plastics remained after 40 weeks. Some plastics require UV light to degrade. Transmittance of UV through oxo-biodegradable and standard polyethylene decreased as a consequence of fouling such that these materials received ～ 90% less UV light after 40 weeks. Our data indicate that compostable plastics may degrade relatively quickly compared to oxo-biodegradable and conventional plastics. While degradable polymers offer waste management solutions, there are limitations to their effectiveness in reducing hazards associated with plastic debris.     

Kontinuierliche Schwärzungskurven und diffuse Röntgenstrahlen-reflexe bei Einschlußverbindungen

Ohne ZusammenfassungHerrn Professor Dr. O. H.Erdmannsdörffer zur Vollendung seines 75. Lebensjahres in Dankbarkeit gewidmet.