Untersuchung über die Homopolymerisation des Triallylcyanurats

The homopolymerization of triallylcyanurate (TAC) occuring between 280 and 580 K, has been investigated using a differential scanning calorimeter. Two exotherms are observed. The amount of energy developed is depending on the content of initiator added. It is suggested, that the polymerization is retarded by the growing of the network, so crosslinking is not complete. At temperatures above 558 K the mobility of the network is increased due to the isomerization of the TAC and total crosslinking is taking place. An estimation of the heat of reaction from the decrease in double bonds supports this suggestion.     

Untersuchung über die Wirkung enzymatischer Vorwaschmittel

Investigation on the Action of Enzymatic Prewashing Agents Sections of Krefeld standard cotton fabrics were uniformly soiled with blood, condensed milk, cocoa and egg yolk. After varying storage periods and denaturating treatments the soiled fabrics were soaked in or mechanically prewashed with enzyme-containing and enzyme-free solutions. Finally, a boiling and a peroxide bleach followed. The effect of enzyme-containing and enzyme-free washing agents on the soil removal was checked by measuring the degree of whiteness and protein content. The degree of whiteness provides information of limited use, whereas, extensive conclusions on the washing agent can be obtained from the protein determinations.     

Untersuchung über die anionenadsorption mit hilfe markierter ionen

From previous work, the adsorption of anions is regarded as an essential factor for the different corrosion behaviour of metals in solutions containing different anions. Adsorption is measured by means of ³⁶Cl⁻, ⁸²Br⁻, ¹⁸ F⁻, ³⁶ClO₄⁻, ³⁵O₄²⁻, H³⁵S⁻ and ¹⁴CN⁻ on Pt, Ni and Fe in the form of sheets and evaporated films. Besides the determination of the adsorption after dipping into the solution, a method has been developed for the measurement of adsorption in contact with the solution and for the determination of its kinetics. The method can also be applied to O₂-free metal surfaces produced under vacuum. In this case, however, very rapid adsorption is observed, whereas normally saturation is reached only after many hours. It is concluded that, in general, exchange between oxygen on the metal and the anion takes place rather than simple adsorption.

The distribution of the anions adsorbed on the metal surface has been studied by autoradiography; adsorption takes place preferentially at the grain boundaries and increases when the crystal size decreases.

These results confirm the interpretation of passivation as a competition between various processes: metal dissolution, coverage by a passivating oxide film, and displacement of oxygen by anions.     

Untersuchungen über die Lipide von Kartoffeln

Investigations on the Lipids of Potatoes Gas chromatographic investigations on the fatty acid composition of the total lipids of freeze-dried potato showed that 90% of the fatty acids consist of linolenic, linoleic, palmitic and stearic acids. In all, 31 different fatty acids were detected and identified. Noticeable amounts of odd-chain fatty acids and those having more than 20 C-atoms (up to C₃₀) were found. Eight different varieties of potato were investigated. Difference in the fatty acid composition of the individual varieties was not appreciable. Experiments on the group separation of lipids showed that they contain a large amount of phospholipids (especially lecithin and cephalin). Appreciable amounts of triglycerides were also found, however, the sterol esters, sterols and free fatty acids were present to a lesser extent.     

Untersuchungen über die Autoxydation von Margarine

Investigations on the Autoxidation of Margarine The authors investigated the influence of storage temperature, packing and of the quality of dispersion on the oxidative stability of margarine. The oxidative stability of margarine is improved with increasing fineness of the dispersion. The autoxidation can be prevented to a great extent by employing low storage temperature and suitable packing material. Packing materials containing traces of heavy metals promote the autoxidation in the upper layer of margarine.     

Untersuchungen über die toxikologischen Eigenschaften von Waschmittelenzymen

Investigations on the Toxicological Properties of Enzymes Used in Washing Agents Enzymes used in washing agents and enzyme-containing washing agents were tested in animal experiments for their general and local tolerance. The results of these investigations confirm that enzymes employed in washing agents are not toxic. The amounts of enzymes that are added to washing agents do not alter the local tolerance of such products. Similar observations were made in dermatological investigations on testpersons. From the results, it may be concluded that enzyme-containing washing agents do not present any hazard to the health of consumers. The same is also true for allergic reactions. Enzymes used in washing agents do have histamine-and kinin-liberating properties, however, only at such concentration-ranges that are insignificant for the practice.     

Kinetische Untersuchungen über die Autoxidation von Olefinen

Kinetic Studies on the Autoxidation of Olefins The oxidabilities \documentclass{article}\pagestyle{empty}\begin{document}$ {{{\rm k}_{\rm p} } \mathord{\left/ {\vphantom {{{\rm k}_{\rm p} } {\sqrt {2{\rm k}_{\rm t} } }}} \right.\kern-\nulldelimiterspace} {\sqrt {2{\rm k}_{\rm t} } }} $\end{document} at 50°C were determined for 37 olefins, using chlorobenzene as the solvent and azodiisobutyronitril as the initiator. In the group of acyclic aliphatic olefins the oxidability rises with increasing number of alkyl groups bound to the double bond. This is also true for cyclic olefins, but in this case the ring size has also a great influence on the oxidability. So the oxidability decreases from five-ring to eight-ring cycloolefins. Particularly high oxidabilities are found in the case of olefins in which a phenyl group is attached directly to the C C-double bond.     

Untersuchungen über die Haltbarkeit der Struktur von Margarine

Studies on the Structural Stability of Margarine In certain cases the stability of the structure of margarine is considerably impaired due to recrystallization of the solid phase. Microscopic studies, differential thermoanalysis and chemical methods were employed in order to gather an insight in the relationship between the composition of margarine fats and the occurrence of such structural alterations.     

Untersuchungen über die Verknäuelung von technischen Polyisobutylenen

With technical grade polyisobutylenes (Oppanole B of BASF), light scattering in n-hexane, osmotic pressure in toluene, and intrinsic viscosity in different solvents are measured. The data are used to derive polydispersity, degree of coiling, and coil expansion of the samples. The undisturbed dimensions are estimated.     

Untersuchungen über die Verseifungsfarbzahl

Studies on the Saponification Colour Number Oxidized fats give yellow to brown solutions on saponification with alcoholic potassium hydroxide. Studies reported here were directed towards determining the causes of such reactions. The results indicate that at least two multiple bonds which are conjugated in relation to the carbonyl group, or a α,β-dicarbonyl group give a strong reaction on heating with alcoholic potassium hydroxide. It is shown that under certain conditions of reaction the saponification colour number is suitable as a measure for the degree of oxidation of heated fats. The method employed is described.     

Kinetische Untersuchungen über die Addition von Halogenwasserstoffen an Olefine

Kinetic Studies on the Addition of Hydrogen Halides to Olefins The relative rates of the reactions of olefins with hydrogen bromide and iodide were determined in acetic acid solution. The kinetic data of the substituted styrenes were correlated by means of the Hammett equation, those of the open-chain aliphatic olefins were correlated by means of the three- and the five-parameter Taft equations. All correlations show the transition state to be similar to an open carbenium ion.     

Biokinetische Untersuchungen über die Resorption von Aminosauren beim Menschen

Biocinetic Investigations of Resorption of Amino-Acids in Human Beings Biocinetics — as pharmacocinetics For years an unrenouncable part of the clinical pharmacology — is a procedure to gain quantitative statements about conversion factors and resorption processes by means of calculation models. For that purpose two basic requirements are necessary: 1. It should be possible to describe the elimination of the investigated compounds from blood by equations of first order, that means increase in concentration and velocity of elimination have to be proportional. This is given for most of the investigated substances, and for amino-acids, too. Key factor is a compound specific elimination constant (k₂) of the exponential equation. 2. The distribution volume of the substance must be known. It is to determine by intravenous infusion of known quantities of the compound. For aminoacids it ranges from 674 (PHE) to 212 (TRP) ml/kg body weight. By mathematical operations like eliminating the elimination processes from concentration/time curves after oral application qualitative and quantitative informations about the entry of resorbed amino-acids into the periphere circulation and by that about the biological use of the applicated amino-acids can be gained.     

Über die Wechselwirkungen zwischen Blut und Sauerstoffbleichmitteln sowie über die Problematik von enzymatischen Vollwaschmitteln

Interaction between Blood and Oxygenating Bleaching Agents and Problems Involving Enzyme-Containing Washing Agents Haemoglobin catalyzes the decomposition of perborate during the action of washing agents on blood, thus leading to fixation of denaturated blood. The formation of cystine bridges alone does not explain this fixation. The splitting of H₂S followed by cross-linking in blood protein over the double bonds are considered by the author as important processes as well. Fixed blood can only be decomposed by prolonged action of proteases, enzymatic soaking in the absence of perborate being optimum. The injurious action of perborate on enzymes is not the determining factor in the difficulty encountered in the washing of some blood stains by enzymecontaining washing agents.     

Studien über die Vergilbung und Vergrauung von verschiedenen Faserstoffen

Studies on the Yellowing and Greying of Different Fibres To determine the possible detergent sorption, cotton, rayon, polyamide and polyester texiles were washed repeatedly under different conditions and at the end extracted with benzenemethanol. In the further set of experiments, the washed samples were stored at 60° C for 30 hrs. Large changes in the degree of whiteness appeared, dependent on the storing influence. On washing in the presence of soot, different types of textiles showed noticeably different greying tendencies due to the soot sorption.     

Überblick über die Anwendungsmöglichkeiten von Festelektrolyten

Applications of solid state electrolytes – a survey . Ionic conduction in solids has numerous potential applications in the fields of instrumentation, energy storage, energy conversion, and production of chemicals. The present state of development of the various processes and devices ranges from industrial maturity via application tests and R & D work to projects in the concept stage. The state of the art is briefly reviewed.