The high level idea of enabling keyword search over re-encrypted ciphertext by re-encryption.

<p>The high level idea of enabling keyword search over re-encrypted ciphertext by re-encryption.</p

Property summary for PRES, ABE, ABPRE, ABKS in the literature and the solution in this paper.

<p>Property summary for PRES, ABE, ABPRE, ABKS in the literature and the solution in this paper.</p

Sequence diagram for using in the application where the data owner shares his medical records with some professionals such that only authorized professionals can retrieve medical records of their interests.

<p>Sequence diagram for using in the application where the data owner shares his medical records with some professionals such that only authorized professionals can retrieve medical records of their interests.</p

System model of attribute-based access control for proxy re-encryption with keyword search.

<p>System model of attribute-based access control for proxy re-encryption with keyword search.</p

Synthesis and Characterization of Novel 1,4-Bis(carbazolyl)benzene Derivatives with Blue-Violet Two-Photon-Excited Fluorescence

Novel fluorescent two-photon absorption molecules containing bis­(carbazolyl)­benzene as the central unit and phenylethynyl moieties as peripheral groups (Cz-Ps) are synthesized and characterized. In these molecules, two carbazolyl moieties are linked with benzene at the 9-position and synthesized by a concise process involving nucleophilic substitution between the cyclopentadienyliron complexes of dichloroarenes and phenylethynyl carbazole, followed by photolysis. The optimal structures of Cz-Ps reveal that two carbazolyl rings linked by a benzene ring are not planar. This feature prevents the electron conjugation of the molecule from extending throughout the whole molecule and allows Cz-Ps to realize blue-violet emissions and high fluorescence quantum yield. With increasing number of conjugated phenylacetylene structures in Cz-Ps, the maximal absorption and emission peaks were red-shifted. The quadrupolar compound DMoCz-P shows strong one-photon and two-photon activities. The resulting molecules are also thermally stable with high glass transition temperatures due to the rigid bicarbazole central unit. This work has demonstrated that using bis­(carbazolyl)­benzene as central building block could enhance two-photon absorption (TPA) performance and also provides a possible general synthetic strategy for a series of bis­(carbazolyl)­benzene derivatives, which would advance the understanding of the rational design of new organic optical materials