The dephasing time of the lowest bright exciton in CdSe/ZnS wurtzite quantum dots is measured from 5 to 170 K and compared with density dynamics within the exciton fine structure using a sensitive three-beam four-wave-mixing technique unaffected by spectral diffusion. Pure dephasing via acoustic phonons dominates the initial dynamics, followed by an exponential zero-phonon line dephasing of 109...

Two new tridentate(NNO)-bidentate(NN) compartmental ligands, HL(5) and HL(6), are synthesized from pyridine and benzimidazole synthons. They react in aqueous solution under physiological conditions with Zn(II), Ln(III), or a mixture thereof, to yield complexes of different stoichiometries, 1:3, 2:2, 2:3, 1:1:3, the speciation of which is established by UV-visible titrations and ESI mass spectro...

The mechanisms of exciton dissociation and migration in the conjugated polymer (poly(2-methoxy-5-(2′-ethyl)(hexyloxy)1,4phenylenevinylene))(MEH-PPV)/CdSe nanoparticle hybrid materials were investigated by steady-state and time-resolved photoluminescence spectroscopy. Rapid exciton dissociation at the nanoparticle/polymer interfaces, leading to quenching of the photoluminescence efficiency η and...

Using reflectivity and picosecond time-resolved photoluminescence, we have studied the intrinsic optical properties of negatively charged excitons in modulation doped CdTe quantum wells. In emission, we observe simultaneously a low energy exponential tail in the charged exciton spectral line and a linear increase of its radiative lifetime with temperature. In absorption, we find a consistent de...

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 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...

Recognition of deleterious effects of chlorine and bromine on ozone and climate over the last several decades has resulted in international accords to halt the production of chlorine-containing chlorofluorocarbons (CFCs) and bromine-containing halons. It is well recognized, however, that these chemicals have had important uses to society, particularly as refrigerants, as solvents, as plastic bl...

Non-radiative cell membrane associated Förster Resonance Energy Transfer (FRET) from an enhanced cyan fluorescent protein (ECFP) to an enhanced yellow fluorescent protein (EYFP) is used for detection of apoptosis in 3-dimensional cell cultures. FRET is visualized in multi-cellular tumor spheroids by light sheet based fluorescence microscopy in combination with microspectral analysis and fluores...

The minority carrier lifetime of high-quality ordered GaInP lattice matched to GaAs and the surface recombination velocity at its interface to AlInP were measured using time-resolved photo-luminescence (TRPL) in the temperature range of 77 500 K. The surface recombination velocity was found to be relatively low (under 500 cm/s) over the measured temperature range. The effective lifetime increas...