Untersuchungen zur Steigerung der Trocknungsgeschwindigkeit der Gefriertrocknung

Freeze‐drying offers the advantage of mild drying. However, a drawback is the long drying time. One way to reduce the drying time is to use dynamic freeze‐drying. Here, the heat transfer to the product is improved and the forming dry layer is permanently removed. Thus, the heat and mass transfer resistance is reduced and it is dried in the vicinity of the ice crystals. This results in an increase of the drying rate, since it can be dried in the first drying section.     

Gedanken zur Zukunft der Feststoffverfahrenstechnik

On the Future of Solid Processing Techniques The chemical industry is experiencing major changes. The experts of the “Solids Processing Industrial Network” expect that in the future two kinds of chemical plants will develop: on the one hand the polyvalent, multipurpose, modular plant and on the other hand the world‐scale plants. At the same time the high percentage of solids as products of chemical processes will continue to increase and therefore new challenges have to be met. Small‐scale production of solids has to be customized to the individual customer needs, which means that product design will be a technology that defines the competitiveness. For large plants techniques have to be developed that enable large volumes to be produced but that also allow the reliable scale‐up from laboratory scale to world‐scale production. Automatization will play a crucial role in the success of solids processing, which will depend on the availability of on‐line measurement systems and the development of simulation models for the processes and the particle properties involved.     

Wege zur Verbesserung der Wirtschaftlichkeit der Anlagen zur physikalischen Raffination unter Berücksichtigung des Trennverhaltens der Nebenkomponenten

Methods to Improve Profitability of Physical Refining Plants in Consideration of Separation Behaviour of Secondary Components On a comparative view some possibilities for economical improvements of physical refining plants are discussed in detail. Special consideration is given to the separation behaviour of secondary components. Above all it is shown how losses of natural inhibitors can be reduced perceptibly with counter current film technology and from which affecting factors these losses depend on. Low operating costs require a larger number of the transfer stages with minimum pressure drop. The fulfillment of these conditions requires the use of counter current film type columns. Due to the better mass transfer efficiency a higher oil yield can be achieved. Finally the possibilities to reduce environmental impacts are discussed in detail.     

Ein Mikrowaschtest zur Bestimmung der Enzymwirkung

A Micro Wash Test for the Determination of Enzyme Performance A micro wasch test as well as two test fabrics stained with denatured proteins were developed. Test fabric A (blood-egg) responds only to proteases. When the latter are absent, no change in reflectance occurs either by agitation during washing, by detergents or by electrolytes at any pH below 11.5. Test fabric B (chocolate – milk) also responds only to proteases. In blank wash tests without enzyme no stain remova occurs. On the contrary, in blank tests this test fabric shows increased darkening with increasing pH. With these test fabrics the micro wash test has been used to evaluate the practical performance of very small quantities of enzymes isolated by gel chromatography or electrophoresis.     

Wege zur Intensivzucht in der Teichwirtschaft

Intensification of Pond Fishery Pond fishery has made large progress during past decades. Considerable increase in production was achieved through fertilization with chalk and phosphates, a further progress was the use of dry feeds (pellets). Instead of natural production in ponds, recently net containers are used for growing carps and trouts. Use of automatic feed delivery devices permits growing large number of fish in small space. In the future, heated water from cooling towers can be used, increasingly, for growing fish. The prerequirement for this is, however, good quality of water and sufficient oxygen content.     

Von der Datenverarbeitung zur Wissensverarbeitung?

From data processing to the processing of knowledge . The present article first examines the problems and the claims of artificial intelligence (AI) research. A brief survey of the principal areas of pure and applied AI research then leads to the structure and the basic functions of so-called expert systems. The account closes with a number of critical, yet unsolved questions.     

Coulometrische Schnellmethode zur Bestimmung der Hydrierjodzahl

A Rapid Coulometric Method for the Determination of Iodine Value by Hydrogen Uptake A rapid method for the determination of degree of unsaturation of oils and fats is of importance for the oil and fat industry. In addition to the common methods for the determination of iodine value, alternative methods, based on hydrogenation, are available. In the methods involving hydrogenation of the oil or fat, as described in the literature, hydrogen is either externally added to the system or generated internally by chemical means, such as, by the addition of a standardized sodium boronate solution to the reaction mixture. The authors have mechanized the hydrogenation by generating hydrogen chemically using an electrolytic method in a special coulometric system which excludes the titration step. The iodine value of an oil or fat can be calculated from the current consumed according to Faraday's law. The sample, without prior treatment, is injected and hydrogenated within 2-3 minutes. More than 100 samples can be injected into the same reaction mixture. This method is more exact than the common procedures, because only an addition of hydrogen to the double bonds but no substitution occurs. The iodine values, determined for fats and oils within a range of values between 10 to 190, agree well with the values determined according to Wijs' method. The standard deviation is less than 1%.