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 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 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.     

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 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.     

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.     

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.     

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.     

Untersuchungen über die Wirksamkeit von Konservierungsmitteln in anionaktiven Tensiden II

Investigations on the Efficacy of Preserving Agents in Anion Active Surfactants II The authors investigated the preserving action of p-chloro-m-cresol and of pHB-methyl/ethyl ester combination (1 + 1) in solutions of anion active surfactants. The preservatives were employed at two different concentrations. The concentration of the surfactants (lauryl sulfate and protein-fatty acid condensate as sodium, potassium and triethanolamine salts) was varied from 0.1 to 10.0 g/100 g. The pH of the solutions was 7. The deactivation of the preservatives investigated here by the anion active surfactant occurs only after a certain ratio of surfactant to preservative is reached. Under this ratio the preservatives are fully effective; above this, however, are the preservatives deactivated.     

Untersuchungen über die basisch katalysierte reaktion von melamin mit formaldehyd

Reaction products of melamine and formaldehyde can be modified by treatment with N -diethyl-trimethylsilyl-amine to yield materials, which are soluble in organic solvents and can easily be fractionated by gel permeation chromatography. Moreover, gel permeation chromatography is used for the quantitative investigation of the course of the sodium-hydroxyde catalysed methylolation of melamine. For this purpose the differential refractometer is calibrated to the corresponding peak area in the chromatograms. In the quantitative determination of the methylolation reaction of melamine in alkaline aqueous solution a difference between the injected and the amount calculated from calibration data was observed. This difference is caused by the presence of polyoxymethylene glycols in the methylolmelamines. Polyoxymethylene glycols are also found in technical melamine-formaldehyde resins.     

Untersuchungen über die Wirksamkeit von Konservierungsmitteln in anionaktiven Tensiden I

Investigations on the Effectiveness of Preservatives in Anion Active Surfactants The preserving action of five preservatives was tested at pH values of 6, 7 and 8 in 10% solutions of the anion active surfactants sodium lauryl sulfate, protein-fatty acid condensate and sodium laurylether sulfate. It was found that the three difficultly water-soluble compounds p-chloro-m-cresol, pentachlorophenol and the combined methyl and ethyl esters of the p.H.B. esters are ineffective at usual concentrations. Both of the watersoluble preservatives polyoxymethyleneglycol and chloroacetamide were effective. Furthermore, it was observed that the preservative action of chloroacetamide is enhanced by anion active surfactants. The inactivation of the difficulty watersoluble preservatives is traced back to the solubilization of these compounds by the micelle of the anion active surfactants.     

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.