Complete (17)O chemical shielding (CS) and quadrupole coupling (QC) tensors and their molecular orientations were determined for the central residues in two tripeptides Gly-Gly-Val (GGV) and Ala-Gly-Gly (AGG) by single-crystal NMR methods. Tensor orientations in the two peptides are very similar, however, principal components are different. The most shielded CS and smallest magnitude QC compone...

The electric field gradient (efg) at the Nb site in the intermetallic compounds Nb3X (X = Al, In, Si, Ge, Sn) was measured by the Perturbed Angular Correlation (PAC) method using the wellknown gamma-gamma cascade of 133 482 keV inTa from the decay of Hf, substituting approximately 0.1 atom percent of Nb. The PAC results show that Vzz drops by nearly 40% when X changes from Al to In, and by abou...

We extend our modeling of smart structures to second order piezoelectricity. We show that three different models have to be taken into account, which broadens the scope of the sensors and actuators field. Second order piezoelectricity being compatible with isotropy, we also propose a systematic study of the impact of crystalline symmetries on our models. To cite this article: T. Weller, C. Lich...

Molecular separation technologies such as gel electrophoresis and liquid chromatography coupled with mass spectrometry detection have been the foundations of biomarker discovery. This is because medically significant biomarkers, for example in blood, can be as much as 10 fold less common than the most abundant protein, albumin and detecting these low abundance molecules requires high sensitivit...

We discuss the coupling between flow and other hydrodynamic variables that can occur in the optically isotropic tetrahedratic phase (T d) characterized by a third rank tensor order parameter T ijk. We point out that an applied electric field or an applied temperature gradient will lead to flow. Reciprocally we predict that, for example, a shear flow applied to a tetrahedratic phase leads to an ...

A rough picture is beginning to emerge of the physics behind the maximum gradient that can be sustained in an accelerating structure without producing surface damage at a level sufficient to cause a measurable change in the rf properties of the structure. Field emission sites are known to trigger the formation of so-called plasma spots in regions of high dc or rf surface electric fields. A sing...

Nuclear quadrupole resonance (NQR) is the study of the energy splittings due to interaction of the electric quadrupole moment of the nucleus with the electric field gradient that exists at the nuclear site. Many nuclei with spins greater than Vz have a quadrupole moment and most of these quadrupole moments have been measured and tabulated. Thus, the information gained by studying NQR is the mag...

Contributions to the gas-to-liquid chemical shifts of water arising from the electric field gradient of the surrounding molecules have been calculated as a function of the temperature. Since the theoretical model is based on perturbation theory, this part of the chemical shift may be calculated from quadrupole shielding polarizabilities and statistical mechanical ensemble averages of external e...