Poly(4-vinylpyridine)(P4-VP) nanofiber and fluoresent poly(4-vinylpyridine)/porphyrin(P4-VP/TPPA) nanofiber were respectively prepared by electrospinning. The effect of the concentration of P4-VP/dimethylformamide (DMF) electrospinning solutions on the morphology of P4-VP nanofiber was investigated and it was found that the average diameter of the nanofiber of P4-VP/DMF increased with the increase of the concentration of the spinning solution. After the addition of TPPA to the P4-VP/DMF spinning solution, the diameter of P4-VP/TPPA nanofiber became even due to the increase of the conductivity of the P4-VP/DMF-TPPA solution. The photoluminescent(PL) spectral analysis indicates that the emission peak position of P4-VP/TPPA nanofiber is almost the same as that of pure TPPA at about 650 nm without peak shift, and when it was stored for 20 days, the emission peak of P4-VP/TPPA nanofiber is also at 650 nm, indicating that the fluorescent property of P4-VP/TPPA nanofiber is stable. Fourier-transform iufrared(FTIR) spectrum confirms the chemical composition of the resulting P4-VP/TPPA composite nanofiber.
SONG YanZHAN Nai-qianYU MiaoYANG Qing-biaoZHANG Chao-qunWANG Heng-guoLI Yao-xian
The major aim of this work was to synthesize thio-stabilized CdTe nanoparticles(NPs) in an aqueous solution, which was then enwrapped with cetyltrimethylammonium bromide(CTAB), and finally transferred to the polyvinylpyrrolidone(PVP) matrix by electrospinning. The PVP nanofibers containing CdTe NPs were characterized by scanning electron microscopy(SEM) and transmission electron microscopy(TEM), to observe the morphology of the nanofibers and the distribution of CdTe NPs. The selective area electronic diffraction(SAED) pattern verified that CdTe NPs were cubic lattice. The photoluminescence(PL) spectrum indicated that CdTe NPs existed in an optical style in PVP nanofibers. Moreover, X-ray photoelectron spectra(XPS) revealed that thiol-stabilized CdTe NPs were enwrapped by CTAB, and PVP acted as a dispersant in the process of electrospinning.
WANG Shu-gang YANG Qing-biao BAI Jie SONG Yan ZHANG Chao-qun LI Yao-xian
This article presents a novel catalytic method by combining phase-transfer catalyst, benzyltriethylammonium chloride, with 4-dimethylaminopyridine for the syntheses of glycosyl esters from substituted phenoxyaeetie acids and the peracetate of α-D-l-bromosugars to produee eight novel β-glyeosyl esters in high yields. The struetures of the syn-thesized eompounds were established by IR, MS, ^1H NMR, and ^13C NMR speetra and elemental analyses.
YANG Song-tao ZHANG Suo-qin ZHANG Guang-liang WANG Xiao-ming LI Yao-xian