Ausführung,Eigenschaften und Anwendung von Dosierpumpen in der Verfahrenstechnik

Construction, Properties and Applications of Dosing Pumps in Processing Technology The construction of package-type dosing pumps is described. In addition to the stroke-adjustible driving mechanism, the different types of feed parts like piston-, membrane- and bellow-type pumping heads are of special importance. The feeding of small amounts, feeding directly from vacuum with dosing pumps, the dosing accuracy, the influence of the properties of the medium as well as installation problems require special construction. The vast field of application for dosing pumps is demonstrated.     

Ablauf durchgehender Reaktionen sowie Auswahl und Führung von sicheren Prozessen

Runaway Reactions – Their Course and Methods for the Choice and Design of Safe Processes. Literature about runaway reactions is usually concerned with the consequences of explosions such as destruction and emission of hazardous and inflammable substances. DIERS literature describes methods for the design of relief orifices for which experimental studies are necessary. Only few data are available relating to the course of runaway reactions, which, more-over, are also attributable to variety of causes. The present report describes the various process deviations which can trigger a thermal explosion. In addition, the determination of the necessary data and considerations for risk analysis and for the development of inherently safe processes and for lessening the consequences of thermal explosions are discussed. Any possible dangerous process deviation is illustrated with the aid of examples and experimental data obtained in laboratory experiments. The various dangerous process states which can lead to a thermal explosion are thus subjected to systematic study.     

Erfahrungen bei der Hydrierung von einigen Ölen und Fetten mit einem Kupferkatalysator

Experiences on the Hydrogenation of Fats with a Copper Catalyst Soybean oil, rapeseed oil and lard were hydrogenated using a copper catalyst. The products of hydrogenation were refined after the removal of copper following a new technique. The aforesaid oils were also hydrogenated with a nickel catalyst to the same iodine value and then refined. The products of hydrogenation using copper showed a better stability towards oxidation than those obtained with nickel.     

Eine neue Methods zur Einführung von CF3- und C2F5-Gruppen in Pyrimidinderivate und die Anti-Herpes-Aktivität der Verbindungen

A New Method of the Introduction of CF₃- and C₂F₅-Groups into Pyrimidine Derivatives and their Antiherpes Activity A new method of the perfluoroalkylation of uracil derivatives is described. The irradiation of aqueous solutions of uracil and uracilnucleosides with bis-(perfluoroalkyl) mercury (C_nF_2n+1)₂Hg n = 1, 2 under the exclusion of oxygen in the presence of catalytic amounts of azo-bis-isobutyronitril at 254 nm for several hours gave new 5-perfluoroalkylated compounds. In this way we obtained 5-trifluoromethyluracil ( 5a ), 5-pentafluoroethyluracil ( 5b ), 5-trifluoromethyl-2′-deoxyuridine ( 6a ), 5-pentafluoroethyl-2′-deoxyuridine ( 6b ) and 1-(ß-D-arabinofuranosyl)-5-trifluoromethyluracil ( 7a ) in different yields. The perfluoroalkylated compounds were tested against HSV-1 and HSV-2 viruses on human lungefibroblasts. The compounds are markedly less potent than other known nonfluorinated compounds.     

Die Anwendung von Sterculiaöl in der Lack- und Farbenindustrie

The Use of Sterculic Oil in the Paint Industry The author reports the fatty acid composition of the kernel oil of Sterculia foetida fruits from Indonesia, which contained 70% Sterculic acid and describes the experiments for the technological use of this oil for paints, alone or together with linseed oil in the form of stand oils. The opening of the cyclo-propene ring causes easy polymerisation of the oil and can serve for the binding of free fatty acids in the technical lacquer preparations etc.     

Die Fettreifbildung von Schokolade in Abhängigkeit von der verfahrenstechnischen Durchführung der Vor- und Erstarrungskristallisation

Dependence of Bloom-Formation in Chocolate from Technical Operation of Pre-Crystallization and Solidification The undesired bloom-formation in chocolate is caused by post-crystallization of cocoa fat during storage. Experiments were carried out systematically in order to reveal, in what manner the bloom-formation is dependent on pre-crystallization and solidification operations. It was found that chocolate is more resistent to bloom-formation, higher the amount of fat that crystallizes out during pre-crystallization. Increased stability of strongly pre-crystallized chocolate with respect to bloom-formation is due to transformation of cocoa fat into a stable crystalline state, already during pre-crystallization and solidification.     

Verfahrenstechnische Kriterien bei der Auswahl von Flüssigkeitspumpen

Process technological criteria in the selection of liquid pumps . The safety and availability of liquid pumps for process technology plants is of prime importance, because the breakdown of a “critical” pump can close an entire plant and through interruption of production often causes inestimable costs. Some important considerations in selecting the correct pump are therefore given, with regard to mode of action and versatility, from the point of view of process technology. Economic considerations can only be briefly dealt with.