738 research outputs found
Angular correlation studies of conversion electrons from 154Gd, of nuclear electrons from 48V and of bremsstrahlung from unpolarized electrons
No full textApplied Science
Evaluation of Genetic Variability of Kenyan, German and Austrian Isolates of Exserohilum turcicum using Amplified Fragment Length Polymorphism DNA Marker
No full textEighty nine Exserohilum turcicum isolates comprising 56 Kenyan, 26 German and 7 Austrian isolates were isolated from diseased maize plants and cultured on complete liquid medium to generate mycelium for DNA extraction. DNA extraction was done following the CTAB method, DNA purified using spermidin and fingerprinting conducted using Amplified fragment length polymorphism (AFLP) procedure. NTSYSpc, pop gene and Arlequin programs were used to analyze the data and to generate the dendograms. The number of amplified bands and polymorphism varied with the different primer combinations with primer combinations E-ACA/T-CCA, E-ACA/T-CAC, E-ACA/T-CGA, E-ACA/T-CTA revealing a high (79%) level of polymorphism. Cluster analysis of the 607 polymorphic bands from these primer combinations using UPGMA algorithms generated dendograms with 7 main AFLP groups with isolates from different localities grouping together with only two outliers. Pair wise similarity matrix derived with SIMQUAL program showed a wide variation in the AFLP fingerprint of the E. turcicum isolates. Nei’s genetic distance matrix showed that the three populations of E. turcicum isolates differed genotypically with the Kenyan isolates being more genetically related to Austrian isolates (genetic identity of 0.9998) whereas the isolates from Germany and Austria were more diverse (genetic identity of 0.9978). This study showed that AFLP marker is useful in the study of genetic variation of E. turcicum and the pathogen has a high level of genetic diversity
Littoral drift computations on mutual wave and current influence
No full text11th Conference on Coastal Engineering in London 1968, the author presented a method for computing the littoral drift starting from the longshore current velocity as this is generated by the waves and with the assumption that the material is stirred up by the waves. In this paper measurements in a model basin are described by which the procedure is further tested. A comparison with littoral drift rates computed by this procedure and derived from accretion and erosion rates along the coast of Queensland (Australia) are presented. For a hypothetical coast the littoral transports with varying bed roughness are computed. The influence of this roughness on the assumptions forming the basis of the computation procedure is discussed.Hydraulic EngineeringCivil Engineering and Geoscience
Scour underneath submarine pipelines
No full textThis report deals with the physical experiments on scour underneath submarine pipelines, carried out as part of the MaTS project on the stability of submarine pipelines. Moreover, these experiments, which have been carried out in the laboratory for fluid mechanics of the Department of Civil Engineering of the Delft University of Technology, are the topic of the student thesis of the author, who has been joining the Group of Coastal Engineering as a student assistant. His work has been accompanied by ir. W. Leeuwestein. Prof.dr.ir.E.W.Bijker was the supervisor of the entire project on the stability of pipelines. After the introduction in chapter 2, in chapter 3 a summing up is given of the previous research on the subject and the theory needed to approach the problem of the scour process underneath pipelines. In the following chapter a description is given of the way in which the experiments have been carried out. Chapter 5 gives the results of the experiments and using the results a functional relation has been tried to find between the scour depth on the one hand and the flow, pipe and sand parameters on the other hand. In chapter 6 the use of physical experiments to predict prototype scour depths is discussed by studying the concerning scale relations. This thesis ends with some conclusions.Civil Engineering and Geoscience
Sediment concentration and sediment transport due to action of waves and a current
No full textCivil Engineering and Geoscience
Offshore sediment transport and equilibrium beach profiles
No full textCivil Engineering and Geoscience
Zandwinning in de Noordzee
No full textHet hoofdontwerp vormt een studie naar de invloed van een verdieping van de zandbodem op de stabiliteit van de kust. Dit wordt gedaan ter hoogte van IJmuiden.Hydraulic EngineeringCivil Engineering and Geoscience
Golfbreker te Sines
No full textIn het kader van het afstuderen wordt een studie verricht die zal leiden tot een nieuw ontwerp van de bezweken golfbreker te Sines, Portugal. De uitgangspunten voor dit ontwerp zijn: - het alignement van de te ontwerpen golfbreker zal samenvallen met dat van de bestaande. - er wordt een ontwerp gemaakt onafhankelijk van de bestaande situatie, waarbij er van wordt uitgegaan, dat op de bestaande plaats nog niets is gebouwd. Het vooronderzoek is het eerste deel van deze studie. Allereerst zal worden ingegaan op het bestaande ontwerp, de uitgangspunten die daaraan ten grondslag hebben gelegen, de omstandigheden van bezwijken en de aard van de opgetreden schade. Het tweede deel is het hoofdontwerp van de golfbreker te Sines. Het derde deel bestaat uit de golfhoogten bij de golfbreker Cap Sines.KustwaterbouwkundeHydraulic EngineeringCivil Engineering and Geoscience
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