Stimuli-Responsive Ti-Organic Gels and Aerogels Derived from Ti-Oxo Clusters: Hierarchical Porosity and Photocatalytic Activity.

Herein, we report titanium-organic gels (TOGs) as new Ti-oxo-based materials that exhibit stimuli-responsive sol-gel transformations and hierarchical porosity upon the removal of solvent molecules. Heating a solution of Ti-oxo clusters and pyromellitic acid as a tetratopic ligand produces TOGs that readily become sols by applying physical stimuli such as shaking or vortexing under ambient conditions. Porous titanium-organic aerogels (TOAs) were obtained by the CO supercritical point drying (CPD) of the TOGs, and their porous structures were characterized by N adsorption and desorption isotherm measurements.

Manipulating nanoscale interactions in a polymer nanocomposite for chiral control of linear and nonlinear optical functions.

The design, synthesis, and supramolecular organization of a nanocomposite in which nanoscale excitonic interactions between quantum dots and the chiral polymer dramatically enhance the optical activity is reported. This material is highly suitable for application in the emerging field of chiral photonics.

Superior optical limiting, stabilization, and spatio-temporal reshaping of ultrashort laser pulses in an opto-stable intrinsic polymer film.

A chemically modified poly(fluorene-alt-benzothiadiazole) (PFBT) polymer film is reported to exhibit high two-photon absorbing capability and chemical/physical stability upon the action of high-power laser pulses of ~780 nm wavelength and ~160 fs duration. A nonlinear transmission measurement is conducted by varying the input intensity from ~20 to ~600 GW/cm2, the corresponding nonlinear transmission of a ~70 μm thick film is reduced from ~0.8 to 0.

Synthesis and characterization of dithienylbenzobis(thiadiazole)-based low band-gap polymers for organic electronics.

New donor-acceptor alternating conjugated polymers were synthesized and characterized. Among them, PCPBBT exhibited a band-gap of 1.01 eV and ambipolar characteristics with μ(h) = 7.

Chiral poly(fluorene-alt-benzothiadiazole) (PFBT) and nanocomposites with gold nanoparticles: plasmonically and structurally enhanced chirality.

Materials with large chiral optical activity at visible wavelengths are of great interest in photonics, particularly as a route to chiral optical metamaterials. Here, we demonstrate the plasmonic enhancement of the chiral optical activity of chiral poly(fluorene-alt-benzothiadiazole) (PFBT) doped with gold nanoparticles. The supramolecular helical organization of polymeric chains with simultaneous dipole-dipole interaction of the helically ordered nanoparticles with the polymer and one another results in unprecedented values of chirality parameter (κ ~0.

Excavation of lead compounds that inhibit mast cell degranulation by combinatorial chemistry and activity-guided.

An allergic reaction ensues after antigen binds to mast cell or basophil high affinity IgE receptor, Fc epsilonRI, resulting in degranulation of various inflammatory mediators that produce various allergic symptoms. In this study, i) we isolated the active component for the inhibition of mast cell degranulation from the extract of leaves of Castanea crenata and identified it as quercetin; ii) we established the total synthesis procedure of quercetin; iii) using quercetin as positive control, we excavated some lead compounds that possess inhibitory activities for mast cell degranulation by screening the chemical libraries of 1,3-oxazolidine derivatives prepared by solid phase combinatorial chemistry. Some of 1,3-oxazolidine compounds possessing acetyl and 3',4'-dichlorophenyl group displayed strong inhibitory activities on Fc epsilonRI-mediated mast cell degranulation, suggesting that they can be used as lead compounds for the development of anti-allergic agents.