Structure and electrical properties of Pr ans Sm doped CeO2 and Ce2MoO15 based solid electrolytes

Sin and Pr doped CeO2 and Ce6MoO15 based materials were synthesized by sol-gel method. The structure of the powders were characterized by X-ray diffraction (XRD), Raman spectra, field emission scanning electron microscopy(FE-SEM) and the electrical conductivity of the samples was investigated by AC impedance spectroscopy. By comparing the structure and electrical properties of different systems, it could be concluded that the electrical property of Ce6MoO15 based system is better than that of CeO2 system. The added Mo element resulted in the increase of gain size and improved the grain boundary conductivity notably below 600 degrees C, while the Pr dopant induced the smaller grain size and improved the grain boundary conductivity of the materials.

Tuning of emission: Synthesis, structure and photophysical properties of imidazole, oxazole and thiazole-based iridium (III) complexes

Three new iridium (III) complexes with two cyclometalated (CN)-N-boolean AND ligands (imidazole, oxazole and thiazole-based, respectively) and one acetylacetone (acac) ancillary ligand have been synthesized and fully characterized. The structure of the thiazole-based complex has been determined by single crystal X-ray diffraction analysis. The Ir center was located in a distorted octahedral environment by three chelating ligands with the N-N in the trans and C-C in the cis configuration. By changing the hetero-atom of (CN)-N-boolean AND ligands the order S, O and N, a marked and systematic hypsochromic shift of the maximum emission peak of the complexes was realized. The imidazole-based complex emits at a wavelength of 500 nm, which is in the blue to green region. The tuning of emission wavelengths is consistent with the variation of the energy gap estimated front electrochemistry results. An electroluminescent device using the thiazole-based complex as a dopant in the emitting layer has been fabricated. A highly efficient yellow emission with a maximum luminous efficiency of 9.8 cd/A at a current density of 24.2 mA/cm(2) and a maximum brightness of 7985 cd/m(2) at 19.6 V has been achieved.

Mechanism of phase transformation and formation of barium hexaferrite doped with rare-earths in sol-gel process

The phase-transformation in sol-gel preparation of barium hexaferrite and the formation of barium hexaferrite doped with La3+ Were studied by chemical phase analysis, X-ray diffraction and infrared spectrometry analysis. The experimental results show that phase transformation reactions of FeCO3, Fe2O3 and BaFe2O4, barium hexaferrite and gamma-Fe2O3 take place in the heat treatment of gel. While the doping lanthanide ion replace barium ion, an equivalent quantity of Fe3+ are reduced to Fe2+ to maintain the charge equilibrium.

Multilayer assemblies of colloidal ZnS doped with silver and polyelectrolytes based on electrostatic interaction

Multilayer assemblies of silver doped ZnS colloid and polycation were fabricated by a self-assembly technique exploiting electrostatic interaction. UV/Vis spectra showed the uniform deposition process and X-ray photoemission spectroscopy (XPS) confirmed the coexistence of silver. It was found that the emission spectra of the silver doped ZnS colloid red-shifted to 528 nm comparing with undoped ZnS colloid. However, the most important finding was that the luminescence intensity of doped ZnS assembled in films was much stronger than that of undoped ZnS in films and that of doped ZnS in the spin-casting film. The mechanism of the enhancement luminescence was discussed. (C) 1998 Elsevier Science S.A. All rights reserved.

Possible suppression of exogenous beta-1,3-glucanase gene gluc78 on rice transformation and growth

Three genes encoding for fungal cell wall degrading enzymes (CWDE), ech42, nag7O and gluc78 from the biocontrol fungus Trichoderma atroviride were transformed into rice mediated by Agrobacterium tumefaciens singly and in all possible combinations. A total of more than 1800 independently regenerated plantlets in seven different populations (for each of the three genes and each of the four gene combinations) were obtained. Our data indicated that gluc78 gene had negative effects on transformation frequency and plant growth. Some regenerated plants with gluc78 gene were stunted; spontaneously produced brown specks; could not tassel. The combination with either one of the two other genes (ech42, nag70) present in the same T-DNA region reduced the negative effect of gluc78 on plant growth. These results indicated that expression of several genes in one T-DNA region interfered with each other and expression of exogenous gene in recipient plant was a complex behavior. (c) 2007 Published by Elsevier Ireland Ltd.

Method for improving classification performance of neural network based on fuzzy input and network inversion

In order to effectively improve the classification performance of neural network, first architecture of fuzzy neural network with fuzzy input was proposed. Next a cost function of fuzzy outputs and non-fuzzy targets was defined. Then a learning algorithm from the cost function for adjusting weights was derived. And then the fuzzy neural network was inversed and fuzzified inversion algorithm was proposed. Finally, computer simulations on real-world pattern classification problems examine the effectives of the proposed approach. The experiment results show that the proposed approach has the merits of high learning efficiency, high classification accuracy and high generalization capability.