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The effect of residual stresses generated by load history on fracture has been investigated through experimental and numerical studies. In this paper the application of a “local approach” to determine the change in applied load to cause fracture is described. Then the R6 defect assessment procedure is presented. The effect of tensile residual stress on brittle fracture of ferritic steel type A533B at -150ºC is explored. The modified J-integral, J has been also used to estimate the combined crack driving force during loading to fracture of the specimens containing tensile residual stresses ahead of a crack/notch. It is shown that by having more accurate estimates of driving force created by the residual stresses leads to increased agreement between experiments and assessment.

This Chapter deals with the evaluation of the pore size of crystalline microporous solids with molecular probes. Only methods where the dimensions of the probe molecules and the pore width are similar are discussed. This means that the adsorption or the selectivities and/or conversions of the reaction depend, in an unambiguous manner, on the pore width. After the introduction, in Sect. 2, some general aspects are discussed that are important for the detailed understanding of the methods covered, namely dimensions of probe molecules and intracrystalline cavities as well as molecular sieving. Section 3 is devoted to adsorption, i.e., the use of molecular probes without chemical reactions. This includes mainly the characterization of various zeolites in comparison with one another and the discussion of molecular probes for zeolites with different pore sizes. Finally, in Sect. 4 shape-selective catalytic reactions are reviewed which have been employed for characterizing the width of micropores. As an introduction, the basics of shape-selective catalysis in microporous materials are discussed. The main test reactions dealt with are, for monofunctional acidic molecular sieves, the competitive cracking of -hexane and 3-methylpentane (Constraint Index) as well as the isomerization and disproportionation of -xylene. For bifunctional molecular sieves, the isomerization and hydrocracking of long-chain -alkanes (Refined or Modified Constraint Index) as well as the hydrocracking of C cycloalkanes such as butylcylohexane (Spaciousness Index) are reviewed.

This Chapter deals with the evaluation of the pore size of crystalline microporous solids with molecular probes. Only methods where the dimensions of the probe molecules and the pore width are similar are discussed. This means that the adsorption or the selectivities and/or conversions of the reaction depend, in an unambiguous manner, on the pore width. After the introduction, in Sect. 2, some general aspects are discussed that are important for the detailed understanding of the methods covered, namely dimensions of probe molecules and intracrystalline cavities as well as molecular sieving. Section 3 is devoted to adsorption, i.e., the use of molecular probes without chemical reactions. This includes mainly the characterization of various zeolites in comparison with one another and the discussion of molecular probes for zeolites with different pore sizes. Finally, in Sect. 4 shape-selective catalytic reactions are reviewed which have been employed for characterizing the width of micropores. As an introduction, the basics of shape-selective catalysis in microporous materials are discussed. The main test reactions dealt with are, for monofunctional acidic molecular sieves, the competitive cracking of -hexane and 3-methylpentane (Constraint Index) as well as the isomerization and disproportionation of -xylene. For bifunctional molecular sieves, the isomerization and hydrocracking of long-chain -alkanes (Refined or Modified Constraint Index) as well as the hydrocracking of C cycloalkanes such as butylcylohexane (Spaciousness Index) are reviewed.

Xenon is an inert gas with a very large electron environment that makes it sensitive to any interaction, even physical. In the case of Xe isotope (spin 1/2), the resulting electronic perturbation is directly transmitted to the nucleus and, therefore, affects the nuclear magnetic resonance chemical shift. In this chapter, we report some applications of this technique in both fundamental and applied research in the field of microporous and mesoporous solids.

Xenon is an inert gas with a very large electron environment that makes it sensitive to any interaction, even physical. In the case of Xe isotope (spin 1/2), the resulting electronic perturbation is directly transmitted to the nucleus and, therefore, affects the nuclear magnetic resonance chemical shift. In this chapter, we report some applications of this technique in both fundamental and applied research in the field of microporous and mesoporous solids.

Xenon is an inert gas with a very large electron environment that makes it sensitive to any interaction, even physical. In the case of Xe isotope (spin 1/2), the resulting electronic perturbation is directly transmitted to the nucleus and, therefore, affects the nuclear magnetic resonance chemical shift. In this chapter, we report some applications of this technique in both fundamental and applied research in the field of microporous and mesoporous solids.