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Rare-earth metal (Eu) doped aluminum nitride has potential application as luminescence materials due to its unusual mechanical and physical properties, as well as high chemical stability. Here we investigate the energetics, local structure and optical and electronic properties by means of a combination of experimental observations (XDR, SEM, HR-TEM and XANES) and first-principles simulations. Present study has revealed that Eu ions are likely to be co-doped with O in the form of Eu-O pairs. Eu ions or Eu-O pairs favor participation at the surfaces of the AlN crystallites. Our analyses show dependences of the Eu valence and electronic/optical properties on the local chemical composition and structure. The obtained information helps us to realize tuning of the optical properties of the luminescent materials via composition and site occupation modification. National Natural Science Foundation of China. Grant Number: 51302029; Fundamental Research Funds for the Central Universities. Grant Number: ZYGX2015J110.

A method is designed to improve the luminescence of AlN-based phosphors by tuning the band structure and crystal structure due to alloying with GaN. The pure (Al,Ga)N:Eu phosphors were initially prepared by gas-phase reaction in an NH3 atmosphere. GaN alloying was used to expand the crystal lattice of AlN due to Ga3+ substituting for smaller Al3+ ions, making dissolution of Eu2+ easier. The dissolution of Ga in the AlN lattice was proven by the result of the Rietveld refinement and the increase in lattice parameters with increasing Ga content. To introduce other energy states mixing with the 5d states of Eu2+, Ga doping was also used to tune the band structure of AlN by acting on Eu2+ ions. The theoretical result was analyzed using the Cambridge Sequential Total Energy Package (CASTEP). According to the calculated total and atom resolved partial density of states, it was observed that the Ga 5p states contribute a large portion to the corresponding Eu2+ absorption band in (Al,Ga)N:Eu phosphors. As a consequence, an enhanced emission intensity at 470 nm and a high quantum efficiency for excitation at 330 nm was obtained despite of stronger thermal quenching of the (Al,Ga)N:Eu phosphors compared with AlN:Eu.

Polypyrrole (PPY) was prepared by the method of chemical oxidation polymerization in ice bath, and a series of products with different morphology or particle size were obtained through changing volume ratio of acetonitrile to water (VRAW) in the mixed reaction solvents. The structures, morphologies, yield, and conductivities of the as-prepared PPY were characterized by FTIR, SEM, electronic balance, and Four-probe conductivity meter. Furthermore, the effect of VRAW on the morphology of the obtained PPY was investigated in detail. As shown from the corresponding results, PPY's average diameter decreased with the increase of VRAW in the range of 1:9 to 4:6, with particle morphology; the film-shaped PPY was obtained when VRAW was in the scope of 5:5 to 7:3. According to the analysis on the polymerization mechanism of pyrrole in the reaction mixture, the change of PPY's morphology was attributed to the structure change of acetonitrile micelle from spherical structure to double layered structure. As the further study shown, the PPY synthesized at a VRAW of 1:9 shows higher yield and conductivity than which prepared in pure water without acetonitrile; however, the further increase of VRAW results in the decrease of the yield and conductivity. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers

CuO and Cu2O are non-noble transition metal oxide supercapacitive materials with high theoretical specific capacitances above 1800 F g−1. In this work, by adjusting organic additives of a colloidal system, Cu, Cu2O, and CuO are grown in situ on nickel foam. CuO exhibits a specific capacitance of 1355 F g−1 at 2 A g−1 in 3 m KOH, a value well above those of Cu and Cu2O (

New aconitine-type C19-diterpenoid alkaloids, N-deethylaconine (I) and beiwutinine (II), are isolated together with hypaconine, mesaconine and 14α-hydroxyneoline.

Three new lycoctonine-type C19-diterpenoid alkaloids, laxicymine 1, laxicymisine 2, and laxicyminine 3 have been isolated from the whole herb of Delphinium laxicymosum var. pilostachyum W.T. Wang. Their structures were established by spectra data.

Five new C18-diterpenoid alkaloids, anthriscifolcines A (1), B (2), C (3), D (4), and E (5), together with a known C19-diterpenoid alkaloid delcorine (6), were isolated from the whole herb of Delphinium anthriscifolium var. savatieri. The structures of these new alkaloids were established on the basis of spectral data (1D- and 2D-NMR, HR-ESI-MS).

Five new C19 diterpene alkaloids, leucanthumsines A (1), B (2), C (3), D (4), and E (5), were isolated from the Chinese medicinal herb Aconitum sungpanense var. leucanthum, together with the known C19 diterpene alkaloids pseudaconine, neoline, 1-O-methyldelphisine, crassicaudine, chasmanine, talatisamine, indaconitine, ezochansmanine, and leueantine D. The structures of these new alkaloids were elucidated by HR-MS and advanced NMR methods, including 1H- and 13C-NMR (DEPT), 1H,1H-COSY, HMQC, and HMBC experiments.

Two new C 1 9 -diterpenoid alkaloids, liljestrandinine (1) and N-deethyltalatisamine (2) were isolated from the roots of Aconitum liljestrandii along with five known C 1 9 -diterpenoid alkaloids: chasmaconitine (4), forestine (5), pengshenine B (6), cammaconine (7), and 6-epi-foresticine (8). Structures were established by spectroscopic method including 2D NMR.