Ersatz des Aufschweißbiegeversuchs durch äquivalente Stahlgütewahl

Replacement of Aufschweißbiegeversuch by equivalent selection of material. The future European Standard family with unified design‐, product‐ and testing standards will not include the AUBI‐test according to SEP 1390 (1996) (Bending test with welded specimen), that was required for certain steel‐works and for plate thicknesses exceeding 30 mm to achieve sufficient material quality. In order to allow authorities to maintain the quality‐level represented by positive results of the AUBI‐tests an equivalence criterion related to Charpy‐V‐impact energy tests was developed in a research project funded by the BASt (Federal Institute of Road Technology). From comparison of test results with test plates selected for purpose and from a large number of results from quality tests carried out by steel producers it was found that for S355 the AUBI requirements can be met if EN 1993‐1‐10 is satisfied and as an additional condition fine grain steel qualities are used for plate thicknesses exceeding 30 mm. For steel grades below S355 also additional criteria for fulfilling the AUBI‐requirements have been derived.     

Zur Theorie der Ortskurven

Ohne Zusammenfassung     

Variability of geotechnical parameters of lateritic gravels overlying contrasted metamorphic rocks in a tropical humid area (Cameroon): implications for road construction

Bulletin of Engineering Geology and the Environment - The variability of the geotechnical properties of lateritic gravels developed on metamorphic rocks from the same clay protolith and of a nearby...     

Localization of the dominant flocculation genes FLO5 and FLO8 of Saccharomyces cerevisiae

In the yeast Saccharomyces cerevisiae three dominant flocculation genes, FLO1, FLO5 and FLO8 have been described. Until now only the FLO1 gene, which is located at chromosome I, has been cloned and sequenced. FLO5 and FLO8 were previously localized at chromosomes I and VIII respectively (Vezinhet, F., Blondin, B. and Barre, P. (1991). Mapping of the FLO5 gene of Saccharomyces cerevisiae by transfer of a chromosome during cytoduction. Biotechnol. Lett. 13 , 47–52; Yamashita, I. and Fukui, S. (1983). Mating signals control expression of both starch fermentation genes and a novel flocculation gene FLO8 in the yeast Saccharomyces. Agric. Biol. Chem. 47 , 2889–2896). This was not in agreement with our results. Here, we report the location of FLO5 and FLO8 on chromosomes VIII and I respectively. By induced chromosome loss and genetic mapping, the FLO5 gene was localized at the right end of chromosome VIII approximately 34 cM centromere distal of PET3. This is part of the region that is present both at chromosome I and chromosome VIII. The location of FLO5 in this area of chromosome VIII made it necessary to re-evaluate the localization of FLO8, which was previously thought to occur in this region. Both genetic and physical mapping showed that FLO8 is allelic to FLO1. Hence, there are only two known dominant flocculation genes, FLO1 and FLO5. Analysis of the nucleotide sequence of chromosome VIII of a non-flocculent strain revealed an open reading frame encoding a putative protein that is approximately 96% identical to the Flo1 protein. This suggests that both dominant flocculation genes encode similar, cell wall-associated, proteins with the same function in the flocculation mechanism.     

Geological,geotechnical, and mechanical characterization of lateritic gravels from Eastern Cameroon for road construction purposes

Bulletin of Engineering Geology and the Environment - Petrographic, mineralogical (X-ray diffraction), and chemical analyses performed on granite-derived lateritic gravels of the...     

Geschwindigkeitsmessungen in Überschallströmungen mit der Elektronenstrahltechnik

Zusammenfassung Zur Messung der Str?mungeschwindigkeiten von überschallschnellen Gasstr?mungen in Windkan?len und Expansionsstr?mungen eignet sich das Ionen-Flugzeit-Verfahren. Als Informationstr?ger dienen Ionen, die mit Hilfe eines Elektronenstrahls aus Molekülen der Gasstr?mung entstehen. Str?mungsgeschwindigkeiten von 300 bis 2500 m/s sind unabh?ngig von Temperatur, Druck und Dichte sehr genau me?bar. Der Dichtebereich reicht von Raumdichte bis in das Gebiet der verdünnten Gase. Das Me?verfahren wurde erprobt in Hyperschalldüsen, Strahlglocken von Satellitentriebwerken, überschallfreistrahlen verschiedener Gasarten sowie Gasgemischen und Molekularstrahlen hoher Intensit?t mit und ohne Kondensationseffekten.     

MA-SEBS对超高分子量聚乙烯/碳纳米管复合材料结晶和熔融行为的影响

以马来酸酐接枝SEBS (MA-SEBS)作相容剂,采用溶液共混的方法制备超高分子量聚乙烯(UHMWPE)/碳纳米管(CNTs)复合材料.熔融结晶的UHMWPE/CNT复合材料是将其熔体以20℃/分的速率降温结晶而成.采用差示扫描量热法(DSC)研究了以不同方式结晶制备的UHMWPE/CNT复合材料的结晶和熔融行为.结果表明UHMWPE/CNT复合材料中UHMWPE相在溶液态结晶比在熔融态结晶形成的晶片厚,因而表现出更高的熔点(Tm)和结晶度(Xc).随着CNTs含量增加,UHMWPE/CNT复合材料中UHMWPE相的结晶温度(Tc)趋于提高.而且MA-SEBS的加入降低了UHMWPE/CNT复合材料中UHMWPE相的Tm 和 Tc. 此外UHMWPE/CNT复合材料中UHMWPE相的结晶速率随CNTs的引入而提高; MA-SEBS起相容剂的作用,改善了CNTs在UHMWPE基体中的分散性,使UHMWPE相的结晶速率进一步提高.