67 research outputs found
Golfdoordringing in een haven
No full textHet doel van dit onderzoek is de invloed te onderzoeken van refractie en diffractie bij zowel langkammige als kortkammige golven bij een haven(-ingang). Dit onderzoek concentreert zich op de invloed van golfvoortplanting nabij een haveningang op golfbeweging in een erachter gelegen havengebied. Er wordt gekeken naar de invloeden van refractie, diffractie, richtingsspreiding en reflecties, en in hoeverre verwaarlozing van deze fysische verschijnselen al of niet acceptabel is. Richtingsspectra met verschillende hoofdrichtingen en energieverdelingen worden doorgerekend. De resultaten in de haven worden vergeleken. Als eerste wordt een sterk geschematiseerde haven(-ingang) genomen, daarna een meer complete haven.Hydraulic EngineeringCivil Engineering and Geoscience
Syntax controle op de grafische specificatietaal SDL
No full textDoor de toenemende complexiteit en grootte van communicatiesystemen wordt het maken van specificaties hiervoor steeds omvangrijker en moeilijker. Specificaties leggen al in een zeer vroeg stadium de beoogde kwaliteit van een systeem vast. Om de problematiek rond het maken van specificaties, de documentatie en het onderlinge vergelijken van systemen te vereenvoudigen heeft de CCITT een specificatietaal ontworpen: SDL (Specification and Description Language). Voor de invoer van de grafische vorm van SDL is op de vakgroep een plotpakket ontwikkeld. Als uitbreiding hierop is een programmapakket ontwikkeld dat de samenhang van de symbolen op een bladzijde kan vinden, de verschillende bladzijden samenvoegt door het koppelen en verwijderen van verbindingssymbolen en het reduceren van het aantal toestandssymbolen. Tenslotte wordt op dit complete schema controle van de syntax uitgevoerd.Applied SciencesElectrotechniekAutomatische Verkeerssysteme
NADH-linked aldose reductase: The key to anaerobic alcoholic fermentation of xylose by yeasts
No full textThe kinetics and enzymology of o-xylose utilization were studied in aerobic and anaerobic batch cultures of the facultatively fermentative yeasts Candida utilis, Pachysolen tannophilus, and Pichia stipitis. These yeasts did not produce ethanol under aerobic conditions. When shifted to anaerobiosis cultures of C. utilis did not show fermentation of xylose; in Pa. tannophilus a very low rate of ethanol formation was apparent, whereas with Pi. stipitis rapid fermentation of xylose occurred. The different behaviour of these yeasts ist most probably explained by differences in the nature of the initial steps of xylose metabolism: in C. utilis xylose is metabolized via an NADPH-dependent xylose reductase and an NAD+-linked xylitol dehydrogenase. As a consequence, conversion of xylose to ethanol by C. utilis leads to an overproduction of NADH which blocks metabolic activity in the absence of oxygen. In Pa. tannophilus and Pi. stipitis, however, apart from an NADPH-linked xylose reductase also an NADH-linked xylose reductase was present. Apparently xylose metabolism via the NADH-dependent reductase circumvents the imbalance of the NAD+/NADH redox system, thus allowing fermentation of xylose to ethanol under anaerobic conditions. The finding that the rate of xylose fermentation in Pa. tannophilus and Pi. stipitis corresponds with the activity of the NADH-linked xylose reductase activity is in line with this hypothesis. Furthermore, a comparative study with various xylose-assimilating yeasts showed that significant alcoholic fermentation of xylose only occurred in those organisms which possessed NADH-linked aldose reductaseApplied Science
The influence of the Ni/Al ratio on the properties of coprecipitated Nickel/Alumina catalysts
No full textApplied Science
The Cul-de-Sac House
No full textThe cul-de-sac is an omnipresent urban morphology encompassing an array of very different situations, whose specificity however is overshadowed by its functional definition. The research confronts the functional conception and challenges its appropriateness. It is firstly established that there is no one definition of a cul-de-sac, but rather that each case needs to be addressed through its own specificity. Secondly, to be able to analyze the character of a dead-end street, the interruption is not seen as a static state, but rather as a change in the urban dynamic, which then leads to thinking of the reason why this change happens, and how this change is consequently manifested in space. Having recognized the uniqueness of each cul-de-sac, the thesis looks into specific cases in the city of Almaty in Kazakhstan, where cul-de-sacs are to be found in the borders between different urban and natural conditions. The analysed spatial characteristics of the urban cul-de-sacs are then used to design a house, as an architectural work where a higher level of specificity can be achieved. This design project is not an attempt to find the ONE cul-de-sac house, but rather an experiment in architectural design, where one term, or more specifically a manifold interpretation of a single term, is used to generate space. In this case, the interpretations of the cul-de-sac as the chosen term, are extracted from the cases in Almaty, using each case as a referent for the design of a corresponding house. The method followed for such an approach is a set of rules that determine the steps of design. With the first rules a level of abstraction is invoked, aiming to detach the architectural work from the urban reference, for it to gain its own identity; the design then goes through steps of further transformations, to then with the last rule, return to -the reference, be embedded in the corresponding context as an additional and last transformative stage
Method for treating vegetable material with acid as well as products obtained with this method
No full textThe present invention relates to a method for treating carbohydrate- containing vegetable material with acid, comprising the steps of: (a) providing a mixture of a carbohydrate-containing vegetable material, an organic acid and, if necessary, water, (b) heating the mixture obtained in step (a) to a temperature of at least 120 °C for some time so as to obtain a mixture comprising an acid-treated insoluble vegetable material, water, a carbohydrate-containing vegetable material that has been rendered soluble and possibly an organic acid, (c) repeating step (b) at least once, with steps (d) and (e) being carried out prior to step (b): (d) separating the acid-treated insoluble vegetable material from the mixture obtained in step (b) so as to obtain a liquid fraction which comprises carbohydrate-containing vegetable material that has been rendered soluble, (e) adding additional carbohydrate-containing vegetable material and possibly additional organic acid to the liquid fraction obtained in step (d), wherein the mixture that is used upon repeating step (b) is the mixture that is obtained in step (e)
Method for treating vegetable material with acid as well as products obtained with this method
No full textThe present invention relates to a method for treating carbohydrate- containing vegetable material with acid, comprising the steps of: (a) providing a mixture of a carbohydrate-containing vegetable material, an organic acid and, if necessary, water, (b) heating the mixture obtained in step (a) to a temperature of at least 120 °C for some time so as to obtain a mixture comprising an acid-treated insoluble vegetable material, water, a carbohydrate-containing vegetable material that has been rendered soluble and possibly an organic acid, (c) repeating step (b) at least once, with steps (d) and (e) being carried out prior to step (b): (d) separating the acid-treated insoluble vegetable material from the mixture obtained in step (b) so as to obtain a liquid fraction which comprises carbohydrate-containing vegetable material that has been rendered soluble, (e) adding additional carbohydrate-containing vegetable material and possibly additional organic acid to the liquid fraction obtained in step (d), wherein the mixture that is used upon repeating step (b) is the mixture that is obtained in step (e)
- …
