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This paper reports experimental results that demonstrate petrophysical and capillary characteristics of compacted salt. The measured data include porosity, gas permeability, pore size distribution, specific surface area, and gas-brine breakthrough and capillary pressure. Salt samples employed in the experiments were prepared by compacting sodium chloride granulates at high stresses for several hours. They represent an intermediate consolidation stage of crushed salt under in-situ conditions. The porosity and permeability of compacted salt showed similar trends to those expected in backfilled regions of waste repositories excavated in salt rock. The correlation between the measured porosity and permeability seems to be independent of the compaction parameters for the range examined in this study. The correlation also shows a different behaviour from that of rock salt. The data of all petrophysical properties show that the pore structure of compacted salt can be better characterized by fracture permeability models rather than capillary bundle ones. Simple creep tests, conducted on the fully-brine-saturated compacted salt samples, yielded similar strain rates to those obtained by a steady-state mechanical model developed from the tests on fully brine-saturated granular salt. A modified procedure is proposed for the evaluation of restored-state capillary pressure data influenced by the material creep. The characteristic parameters for the capillary behaviour of compacted salt are determined by matching the Brooks-Corey and van Genuchten models with the measured data. The Leverett functions determined with different methods agree well.This paper reports experimental results that demonstrate petrophysical and capillary characteristics of compacted salt. The measured data include porosity, gas permeability, pore size distribution, specific surface area, and gas-brine breakthrough and capillary pressure. Salt samples employed in the experiments were prepared by compacting sodium chloride granulates at high stresses for several hours. They represent an intermediate consolidation stage of crushed salt under in-situ conditions. The porosity and permeability of compacted salt showed similar trends to those expected in backfilled regions of waste repositories excavated in salt rock. The correlation between the measured porosity and permeability seems to be independent of the compaction parameters for the range examined in this study. The correlation also shows a different behaviour from that of rock salt. The data of all petrophysical properties show that the pore structure of compacted salt can be better characterized by fracture permeability models rather than capillary bundle ones. Simple creep tests, conducted on the fully-brine-saturated compacted salt samples, yielded similar strain rates to those obtained by a steady-state mechanical model developed from the tests on fully brine-saturated granular salt. A modified procedure is proposed for the evaluation of restored-state capillary pressure data influenced by the material creep. The characteristic parameters for the capillary behaviour of compacted salt are determined by matching the Brooks-Corey and van Genuchten models with the measured data. The Leverett functions determined with different methods agree well.

Cast iron with bainitic matrix and globular graphite, so called austempered ductile iron (ADI), allows the substitution of heat‐treatable steels. The use of ADI in safety‐relevant components requires knowledge of the fracture and fatigue behaviour. Cyclic stress strain behaviour and fatigue life at total strain control and random loading have been investigated at ADI (EN‐GJS‐1000‐5) and pearlitic cast iron (EN‐GJS‐600‐3). In addition fracture mechanic tests at cyclic loading at various stress ratios were carried out.

Die moderne Bauteilsicherheitsbewertung basiert auf Methoden der Bruchmechanik unter Anwendung von bruchmechanischen Kennwerten, die den Werkstoffwiderstand gegen Rissinitiierung und Rissfortschritt sowie das Rissauffangverhalten charakterisieren. Die experimentelle Ermittlung der Rissarrestzähigkeit ist im Allgemeinen jedoch schwierig und aufwendig. In diesem Beitrag werden Korrelationen für die Abschätzung der Sprödbruch-Übergangstemperatur (TNDT) und der Rissarrestzähigkeit (KIa) mit Hilfe einer Übergangstemperatur, die der Rissauffangkraft im instrumentierten Kerbschlagbiegeversuch entspricht, vorgestellt. Als Kriterien für den Zähigkeitsübergang gelten die an Charpy-V-Proben gemessene Rissauffangkraft 4 kN und die nach Master-Curve-Ansatz berechnete mittlere Rissarrestzähigkeit 100 MPa√m. Die für verschiedene Baustähle vorgeschlagenen Korrelationen zwischen den Übergangstemperaturen T(Fa = 4 kN), T(KIa) und TNDT werden am Beispiel des Stahles 18Ch2MFA bestätigt.

Die moderne Bauteilsicherheitsbewertung basiert auf Methoden der Bruchmechanik unter Anwendung von bruchmechanischen Kennwerten, die den Werkstoffwiderstand gegen Rissinitiierung und Rissfortschritt sowie das Rissauffangverhalten charakterisieren. Die experimentelle Ermittlung der Rissarrestzähigkeit ist im Allgemeinen jedoch schwierig und aufwendig. In diesem Beitrag werden Korrelationen für die Abschätzung der Sprödbruch-Übergangstemperatur (TNDT) und der Rissarrestzähigkeit (KIa) mit Hilfe einer Übergangstemperatur, die der Rissauffangkraft im instrumentierten Kerbschlagbiegeversuch entspricht, vorgestellt. Als Kriterien für den Zähigkeitsübergang gelten die an Charpy-V-Proben gemessene Rissauffangkraft 4 kN und die nach Master-Curve-Ansatz berechnete mittlere Rissarrestzähigkeit 100 MPa√m. Die für verschiedene Baustähle vorgeschlagenen Korrelationen zwischen den Übergangstemperaturen T(Fa = 4 kN), T(KIa) und TNDT werden am Beispiel des Stahles 18Ch2MFA bestätigt.

The WIT (What Is There) (http://wit.mcs.anl.gov/WIT2/) system has been designed to support comparative analysis of sequenced genomes and to generate metabolic reconstructions based on chromosomal sequences and metabolic modules from the EMP/MPW family of databases. This system contains data derived from about 40 completed or nearly completed genomes. Sequence homologies, various ORF-clustering algorithms, relative gene positions on the chromosome and placement of gene products in metabolic pathways (metabolic reconstruction) can be used for the assignment of gene functions and for development of overviews of genomes within WIT. The integration of a large number of phylogenetically diverse genomes in WIT facilitates the understanding of the physiology of different organisms.