A series of pyrene derivatives having 4-(N,N-dimethylamino)phenylethynyl groups as the substituent (1-5) have been synthesized and their two-photon absorption properties were investigated. Comparison of two-photon cross section (delta(max)) with related compounds reveals that pyrene is as efficient a pi-center as anthracene in two-photon materials. Moreover, the two-photon cross section (delta(max)) increased with the number of substituents reaching at the maximum value of 1150 GM for the tetra-substituted derivative (5). Furthermore, the two-photon action cross section (Phi delta(max)) of 5 is comparable to that the most efficient two-photon materials. This result provides a useful guideline to the design of efficient two-photon materials bearing pyrene as a pi-center.

These findings support the internal consistency reliability and construct validity of the Korean version of the CQOLC-K. The instrument can be used to measure quality of life in caregivers of cancer patients in clinical and epidemiological research.

A very generous donor: The electrochemiluminescence (ECL) efficiency and radical stability of pyrene, a poor ECL luminophore, are markedly improved as the number of peripheral multidonor units increased in a series of compounds (see picture). Photophysical and electrochemical studies and theoretical calculations have contributed to the understanding of the ECL enhancement, which is a step forward in the development of new light-emitting materials.

No abstract

No abstract