Die ersten organisch-chemischen SynthesenBauer, H.
doi: 10.1007/BF00424496pmid: N/A
114 67 67 1 1 H. Bauer Max-Planck-Institut für medizinische Forschung D-6900 Heidelberg Abstract The first total synthesis of an organic compound, that of the hydrocyanide by C.W. Scheele in 1783 is remembered and it is pointed to its significant effect on further famous syntheses in the first half of the 19 th century. A nearly unknown reaction done by J.W. Döbereiner in 1816 is considered as the precursor of today's technical important syntheses of hydrocarbons and other organic products starting from coal and water. Short biographies of Scheele and Döbereiner are included.
SonnenenergienutzungGetoff, N.; Solar, S.; Gohn, M.
doi: 10.1007/BF00424497pmid: N/A
114 67 67 1 1 N. Getoff S. Solar M. Gohn Institut für Theoretische Chemie und Strahlenchemie der Universität A-1090 Wien Abstract Three systems are investigated. (1) A strong corrosion of the polycristalline n-TiO 2 semiconductor occurs when it is used as an anode in the Fujishima-Honda cell. A probable reaction mechanism for O 2 production is suggested. (2) By illumination of the MB + −Fe 2+ system (λ< 400 nm; pH 2) H atoms are formed as a consequence of energy transfer from the dye to ferrous ions. H-attack on the dye explains the observed instability of the system. (3) Using tris-(2.2′-bipyridyl)-Ru(II)-complexes containing 2 W/W% Eu or Pr, respectively, as photocatalysts for water photolysis a very low hydrogen yield and a strong decomposition of the complex was established.
Taste and the taste of foodsBoudreau, James
doi: 10.1007/BF00424498pmid: N/A
114 67 67 1 1 James C. Boudreau Sensory Sciences Center University of Texas at Houston 77025 Houston Texas Abstract At least 12 distinct taste sensations can be elicited from different parts of the oral cavity by distinct chemical compounds. The chemicals eliciting each sensation are often common constituents of foods, thus the umami sensations arise with stimulation by monosodium glutamate and nucleotides. These sensations can often be related to different physical/chemical stimulus parameters (e.g., bitterness and hydrophobicity) and neural activity in distinct chemosensory channels.
Ökophysiologische Untersuchungen an Pflanzen der Namib-WüsteWillert, D.; Brinckmann, E.; Scheitler, B.; Schulze, E.; Thomas, D.; Treichel, S.
doi: 10.1007/BF00424499pmid: N/A
114 67 67 1 1 D. J. von Willert E. Brinckmann B. Scheitler E. -D. Schulze D. A. Thomas S. Treichel Lehrstuhl für Pflanzenökologie der Universität D-8580 Bayreuth Institut für Botanik der Technischen Hochschule D-6100 Darmstadt Abstract The southern Namib desert has a vegetation cover of mainly succulent plants in which species of the Mesembryanthemaceae are predominant. Climatically this area is characterized by hot and dry days, and cool and humid nights with episodic rainfalls only in winter. In this environment a great number of species perform a crassulaceaen acid metabolism (CAM). The responses of these plants to water stress as well as the regulation of CAM in the natural habitat are described and discussed.
Neue Erkenntnisse auf dem Gebiete der Parasitologie und der parasitären Erkrankungen des MenschenPiekarski, G.
doi: 10.1007/BF00424500pmid: 7393331
114 67 67 1 1 G. Piekarski Institut für Medizinische Parasitologie der Universität D-5300 Bonn Abstract The increasing interest in the parasites of man in the Federal Republic of Germany is connected with the unbounded keenness of German people to travel. They favor southern regions with warm climates which are usually infested with parasites. Thus the general practitioner is nowadays confronted in his daily routine with “imported” pathogenic organisms and diseases as yet unknown to him or with which he need not have reckoned in the past. Furthermore, new information now exists on the development of well-known parasites of our regions, which can be pathogenic to man. Fortunately, new reliable drugs have come on the market, rendering some parasitic diseases harmless.