The stress analysis for a model with initial stresses, which we term a residual stress model, is performed by digital photoelasticity. The stresses applied on the residual stress model are obtained by analyzing both the initial stresses and the resultant stresses. The method used for analyzing the stresses applies the principle of superposition of the stress to photoelasticity, which is a well-...

The Karplus relations for vicinal J couplings, which relate the peptide backbone angles # and q to 3J(HaN) and 3J(HN-C’), have been reparametrized on the basis of measurements made on uniformly 13C/’5N-enriched human ubiquitin and backbone angles derived from the 1.8 8, X-ray structure of this protein (Vijay-Kumar, S.; Bugg, C. E.; Cook, W. J. J. Mol. Biol. 1987, 194, 531-544). For 3J(Ha-N), va...

For plane deformations generated by an arbitrary distribution of tractions applied in a small region on the boundary of an elastic half-plane, the rates-of-decay for displacements, stresses and strain energy density are obtained as functions of complexity of the load distribution. The rates-of-decay increase in proportion to the complexity of the load distribution; i.e., they increase with the ...

We demonstrate, using ethylene, that controlling lower-valence ionization and field-driven excitation dynamics with ultrashort, intense laser pulses allows steering fragmentation reactions of polyatomic molecules along a certain pathway towards a specific set of fragment ions. © 2013 Optical Society of America OCIS codes: 020.2649, 260.5130 Strong laser fields can be used to both initiate and d...

In this paper we examine the influence of periodic islands within a time periodic chaotic flow on the evolution of a scalar tracer. The passive scalar tracer is injected into the flow field by means of a steady source term. We examine the distribution of the tracer once a periodic state is reached, in which the rate of injected scalar balances advection and the molecular diffusion κ. We study t...

We report evidence for a strongly geometry-dependent substituent effect. The rate constants for H-D exchange of the R-hydrogens, (kexch)OR, in a set of 19 !-alkoxy sulfones of known, fixed (or strongly preferred) H-CR-C!-OR torsion angles have been measured. Those of corresponding model compounds lacking the alkoxy group, (kexch)model, were also measured, thereby providing the ratio, kN ) (kexc...

The X-ray POLarimeter (XPOL) is an instrument that will fly on-board the International X-ray Observatory (IXO). We will describe the XPOL setup in IXO and we will compare the IXO requirements with the actual prototype performance. The environmental tests performed on the XPOL prototype (thermo-vacuum, vibration and heavy ions irradiation) show that this technology is ready for a space applicati...