Physiologie des Phenolabbaus bei Rhodococcus spec. P1. Teil 2: Untersuchungen zur Regulation des Phenolabbaus

The phenol-degrading system which can be induced in Rhodococcus spec. P 1 brings about the metabolization of phenol via the β-ketoadipate path (ortho-cleavage of catechol). For the more precise characterization of the degradation performance investigations were made into the influences of different carbon sources: glucose, galactose, ribose, arabinose, xylose, acetate, citricacid, mandelic acid, protocatechoic acid, glycerol, tryptophane, phenylalanine and the complex substrate of nutrient broth as well as succinate, catechol and benzoate. Only the three last-named substances show an influence: succinate inhibits only the synthesis of phenol hydroxylase, catechol and benzoate inhibit the synthesis and activity of phenol hydroxylase. As a comparison of the results with literature shows, even at the same path of degradation there are different regulating mechanismus in the different microorganisms.     

Zur Bemessung unterirdischer Enteisenungsanlagen Teil 1: Chemisch-analytische Methoden der Erkundung und Bemessung

In underground deferrization processes there exists a dynamic cation exchange euquilibrium for Fe-II to the solid phase of the underground when an Fe-II containing ground water is delivered. Methods of investigation for the estimation of the initial oxygen demand and of the Fe-II content of the aquifer are tested and described in detail. At dynamic filtering tests and within the framework of technically simpler batch-tests the oxygen demand was higher than expected according to the stoichiometric Fe-II share. A relatively good agreement was obtained between the results of both procedures. Fe-II bound to solid matter is measured by a developed Fe-III difference method. Fe-II can be extracted and determined also directly with 1,10-phenanthroline. Moreover, the determination method of the distribution coefficient with its influencing factors is described. Finally, the results of regression relations are explained.     

Untersuchungen zur Einzel- und Gemischadsorption von Phenolen an Aktivkohlen. Teil 2: Gemischadsorptionsgleichgewichte des Systems p-Nitrophenol/p-Chlorphenol/Aktivkohle

On the thermodynamic basis of the theory of the Ideal Adsorbed Solution (IAS) a calculation method was used to predict mixture adsorption equilibria from the individual isotherms. The results of the prediction were compared with the results of practical measurements by the example of the adsorption of p-nitro- and p-chlorophenol mixture on the activated carbon DO 4. According to the explanations concerning the graphically represented results, the mean percent differences between calculated and experimental data by the exact solution of the IAS-theory and by a described simplified method were 11 % and 13 %, respectively. It is thus confirmed that the IAS-theory is very well suited for predicting adsorption equilibria for, e.g., phenol mixtures.     

Zur Charakterisierung suspendierter Wasserinhaltsstoffe. Teil 1: Analytische Methoden

Über Möglichkeiten zur Charakterisierung von suspendierten Inhaltstoffen in Oberflächenwässern wird berichtet. Die Kenntnis der Rohwnsserbeschaffenheit, die neben der Konzentrationsangabe Aussagen über Art und Eigenschaften der Partikel einschließt, ist eine Voraussetzung für die Verbesserung der Bemessungsgrundlagen und den optimalen Betrieb von Wasseraufbereitungsanlagen. Es werden Analysenmethoden zur Erfassung des Feststoffgehaltes ausgewählt, die regelmäßig im Betriebslaboratorium durchführbar sind (z. B. Trübung, Zentrifugationswert). Geeignete Möglichkeiten zur Untersuchung der Partikeleigenschaften wie granulometrische, mikroskopische, röntgen- und differentialthermoanalytische Methoden werden diskutiert.