Electric-field-induced phase transitions of (1-x)PbMg(1/3)Nb(2/3)O(3)-xPbTiO(3) crystals studied by optical methods.

The phase transitions of as-grown (1-x)PbMg(1/3)Nb(2/3)O(3)-xPbTiO(3) (PMN-xPT) crystals with PT compositions of x = 0.31 and 0.38 under a dc electric field were observed in a polarization microscope.

Periodically twinned SiC nanowires.

Twinning has been recognized to be an important microstructural defect in nanoscale materials. Periodically twinned SiC nanowires were largely synthesized by the carbothermal reduction of a carbonaceous silica xerogel prepared from tetraethoxysilane and biphenyl with iron nitrate as an additive. The twinned β-SiC nanowires, with a hexagonal cross section, a diameter of 50-300 nm and a length of tens to hundreds of micrometers, feature a zigzag arrangement of periodically twinned segments with a rather uniform thickness along the entire growth length.

The grafting and release behavior of doxorubincin from Fe(3)O(4)@SiO(2) core-shell structure nanoparticles via an acid cleaving amide bond: the potential for magnetic targeting drug delivery.

Fe(3)O(4)@SiO(2) core-shell structure nanoparticles were first prepared and characterized by TEM, FTIR, XPS and XRD. Subsequently the widely used anticancer agent doxorubincin (DOX) was successfully grafted to the surface of the core-shell nanoparticles via an amide bond with the aid of a spacer arm we synthesized. The spacer arm met two needs: one end can couple to the core-shell nanoparticles' surface while the other end was the active -COOH group, which can react with the -NH(2) group of DOX molecules.

Solvothermal synthesis of well-dispersed MF(2) (M = Ca,Sr,Ba) nanocrystals and their optical properties.

MF(2) (M = Ca,Sr,Ba) nanocrystals (NCs) were synthesized via a solvothermal process in the presence of oleic acid and characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectra, UV/vis absorption spectra, photoluminescence (PL) excitation and emission spectra, and lifetimes, respectively. In the synthetic process, oleic acid as a surfactant played a crucial role in confining the growth and solubility of the MF(2) NCs. The as-prepared CaF(2), SrF(2) and BaF(2) NCs present morphologies of truncated octahedron, cube and sheet in a narrow distribution, respectively.

Theoretical modelling of carrier transports in molecular semiconductors: molecular design of triphenylamine dimer systems.

Charge transport in molecular systems and biosystems can be different from that in inorganic, rigid semiconductors. The electron-nuclear motion couplings play an important role in the former case. We have developed a theoretical scheme to employ the Marcus electron transfer theory coupled with a direct diabatic dimer model and the Brownian diffusion assumption to predict the carrier mobility for molecular materials.