— Positron annihilation lifetime spectra have been measured in MgO : OD~ containing ~ 20 ppm of isolated cation vacancies produced by electron irradiation. For the V~ <-> V transformation, the intensities of the longer-lived lifetime components were enhanced slightly when the vacancies trapped holes and reduced when holes were released.

Fluorescence lifetime-resolved images of chlorophyll fluorescence were acquired at the maximum P-level and during the slower transient (up to 250 s, including P-S-M-T) in the green photosynthetic alga Chlamydomonas reinhardtii. At the P-level, wild type and the violaxanthin-accumulating mutant npq1 show similar fluorescence intensity and fluorescence lifetime-resolved images. The zeaxanthin-acc...

We compute the single-particle inverse lifetime, along with the conductivity-derived scattering rate, for a metallic system in an s-wave superconducting state. When both electron-phonon and electron-impurity scattering are included , we find that while these scattering rates are in qualitative agreement, in general quantitative agreement is lacking. We also derive results for the quasiparticle ...

Editorial – Cohabitation, marriage and separation: contrasts in Europe • Premarital cohabitation: more common in the north than in the south p. 2 • Cohabitation leads less often to marriage p. 2 • Fewer men and women are marryingp. 2 • Unions are more short-lived p. 3 • Several unions in a lifetime: a general trend? p. 4 • Box: Study population p. 4 C O N TE N TS are not marrying at all. Unions...

In today's fiercely competitive products market, product warranty has started playing an important role. The warranty period offered by the manufacturer/dealer has been progressively increasing since the beginning of the 20th Century. Currently, a large number of products are being sold with long-term warranty policies in the form of extended warranty, warranty for used products, service contra...

The optical spectra of individual Ag-Au alloy hollow particles were correlated with the particles' structures obtained by transmission electron microscopy (TEM). The TEM provided direct experimental access to the dimension of the cavity, thickness of the metal shell, and the interparticle distance of hollow particle dimers with high spatial resolution. The analysis of correlated spectral and st...

The SPIN extension presented in this article is meant as a way to facilitate the modeling and verification of object-oriented programs. It provides means for the formal representation of some run-time mechanisms intensively used in OO software, such as dynamic object creation and deletion, virtual function calls, etc. This article presents a number of language extensions along with their implem...

Title of Thesis: FABRICATION AND MEASUREMENT OF CESIATED METAL PHOTOCATHODES Nathan A. Moody, Master of Science, 2004 Thesis Directed By: Professor Patrick O’Shea Department of Electrical and Computer Engineering A requirement for accelerator applications such as free electron lasers is a high current, high quality electron beam. This is achieved using a photoinjector, where a drive laser modul...

The high intensity of free electron lasers opens up the possibility to perform single-shot molecule scattering experiments. However, even for small molecules, radiation damage induced by absorption of high intense x-ray radiation is not yet fully understood. One of the striking effects which occurs under intense x-ray illumination is the creation of double core ionized molecules in considerable...

The Metrology Light Source (MLS), situated in Berlin (Germany) is owned by the Physikalisch-Technische Bundesanstalt andwas built / is operated by theHelmholtz-Zentrum Berlin. It is an electron storage ring operating from 105MeV to 630MeV. The MLS serves as the national primary source standard from the near infrared to the extreme ultraviolet spectral region [1]. Users of synchrotron radiation ...