21,922 research outputs found
Curable polyphosphazenes
Class of polyphosphazene polymers can be cured at moderate temperatures by action of moisture. In addition, polymers maintain flexibility when exposed to low temperatures
Optical Theorem and the Inversion of Cross Section Data for Atom Scattering from Defects on Surfaces
The information content and properties of the cross section for atom
scattering from a defect on a flat surface are investigated. Using the Sudden
approximation, a simple expression is obtained that relates the cross section
to the underlying atom/defect interaction potential. An approximate inversion
formula is given, that determines the shape function of the defect from the
scattering data. Another inversion formula approximately determines the
potential due to a weak corrugation in the case of substitutional disorder. An
Optical Theorem, derived in the framework of the Sudden approximation, plays a
central role in deriving the equations that conveniently relate the interaction
potential to the cross section. Also essential for the result is the
equivalence of the operational definition for the cross section for scattering
by a defect, given by Poelsema and Comsa, and the formal definition from
quantum scattering theory. This equivalence is established here. The inversion
result is applied to determine the shape function of an Ag atom on Pt(111) from
scattering data.Comment: 29 pages, 9 Postscript figures, more info available at
http://www.fh.huji.ac.il/~dan
Recovery of “Intrinsic Value” Damages in Case of Negligently Killed Pet Dog
The North Carolina Court of Appeals, in a case where negligent killing of a pet dog with no market value was admitted, has denied recovery of “intrinsic” damages (also called “actual” damages). Shera v. NC State University Veterinary Teaching Hospital, 723 S.E.2d 352 (N.C. App. 2012). Because the holding is narrow and the type of damages denied are not the same as emotional damages, a close look at the decision is warranted
Inhomogeneity and transverse voltage in superconductors
Voltages parallel and transverse to electric current in slightly
inhomogeneous superconductors can contain components proportional to the field
and temperature derivatives of the longitudinal and Hall resistivities. We show
that these anomalous contributions can be the origin of the zero field and
even-in-field transverse voltage occasionally observed at the superconductor to
normal state transition. The same mechanism can also cause an anomaly in the
odd-in-field transverse voltage interfering the Hall effect signal.Comment: 6 pages, 7 figure
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