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Anshun, China

Zhang Y.,Southwest University | Zhang Y.,Anshun College | Chen X.,Southwest University | Yang Y.,Southwest University | And 3 more authors.
Journal of Environmental Sciences

Dissolved organic matter (DOM) plays an important role in the process of mercury release from water body. In this study, the influence of DOM from different sources (DOM R, DOM S and DOM H, extracted from rice straw, compost and humic soil respectively) on mercury reduction was investigated. The molecular weight distribution and chemical composition of DOM from each source were determined using ultrafiltration membrane technique and elemental analysis respectively. The result showed that mercury release from DOM-added samples was much lower than the control; the lowest mercury release flux was observed in the treatment of DOM H, 25.02% of the control, followed by DOM S and DOM R, 62.46% and 64.95% of the control, respectively. The higher saturation degree and lower molecular weight of DOM H was responsible for the highest inhibition degree on the mercury release. The link between DOM H, concentration and mercury flux was also estimated and the result showed that mercury flux was increased with DOM H at lower concentration, while decreased with DOM H at higher concentration. Different mechanism dominated the influence of DOM on mercury release with variation of DOM concentration. © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Source

Zhang L.,Southwest University | Zhang L.,Anshun College | Zhang X.,Southwest University | Luo Z.,Southwest University | Sun M.,Southwest University
Zhongguo Zhongyao Zazhi

Objective: To establish the induction method and culture system of hairy roots of Panax japonicus, and determine ginsenoside Re contents. Method: Hairy roots of P. japonicus was obtained through infecting pre - incubated terrestrial stem with the Agrobacterium tumefaciens strain C58C1; its enlarging culture was carried out on the 1/2MS medium, and growing characteristics were measured. The transformation of T-DNA was examined by PCR and ginsenoside Re content was determined by HPLC. Result: A. tumefaciens strain C58C1 could make terrestrial stem of P. japonicus bring about hairy roots, the max inductivity was 90% when infecting for 25 min. The PCR examination result showed that rolB genes could be inserted into the hair roots of P. japonicus. All hairy roots could synthesize ginsenoside Re, among them, the max content was PJ8 with 60.26 mg·g -1. Conclusion: It was reported for the first time that the induction method and culture system of hairy roots of P. japonicus were established successfully, which provided a foundation for producing high content ginsenoside Re through culturing the hairy roots of P. japonicus. Source

Meng B.,Hunan University | Meng B.,Anshun College | Wang L.-L.,Hunan University | Huang W.-Q.,Hunan University | And 3 more authors.
Applied Optics

We present a procedure to generate slow light with a large group index, wideband, and low dispersion in our suggested photonic crystal waveguide. By modulation of the declinations in the first two rows of air holes, the group index, the bandwidth, and the dispersion can be tuned effectively. Utilizing the two-dimensional plane wave expansion method (PWE) and the finite-difference time-domain method (FDTD), we demonstrate slow light with the group indices of 23, 35, and 45, respectively, while restricting the group-index variation within a 10% range.We accordingly attain an available bandwidth of 40.7, 23.7, and 5.1 nm, respectively. Meanwhile, the normalized delay-bandwidth product stays around 0.45, with minimal dispersion less than 0.2 (ps2 /m) for all the cases. © 2012 Optical Society of America. Source

Zhang S.-J.,Anshun College | Xu C.-H.,Tsinghua University | Chen J.-B.,Tsinghua University | Zhou Q.,Tsinghua University | Sun S.-Q.,Tsinghua University
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis

Fourier transform infrared (FTIR) spectroscopy and second derivative IR spectroscopy were applied to analyze and evaluate different parts of Scorpio. The second derivative IR spectra show clear differences while the origin spectra are quite similar. It was found that proteins are the dominant components in each part and the tail has distinct proteins compared to the others; fats are mainly stored in the trunk; sulfates are ubiquitous in all parts. Interestingly, the back part of the trunk of degenerative Scorpio contains some purine. It was demonstrated that FTIR spectroscopy integrated with second derivative IR spectroscopy not only can offer a fast, comprehensive and objective methodology for analyzing and evaluating the micro-differences among the various parts of same medicinal materials, but also can provide a rational guidance for medicinal and pharmacological studies. Source

Li Z.,South-Central University for Nationalities | Li Y.,East China Normal University | Li Y.,Anshun College | Li J.,South-Central University for Nationalities
Journal of Chemical Physics

We perform density functional studies of the support effects on the gold-catalyzed dissociation of H2 using the model clusters (Au 10 and Au13) on ZnO(101) surface and find that H 2 prefers to adsorb on the bottom layer of Au clusters on the ZnO surface. The interaction energies of H2 are exponentially correlated with the H-H and H-Au bond parameters. The dissociation of H2 easily occurs on the bottom layer with the energy barriers no more than 0.44 eV. The support effects on the dissociation barriers are greatly dependent on the H-H bond distance in the transition state (TS), i.e., the early TSs with small barriers have larger support effects than the late TSs with large barriers. We find that the charge transfer from the gold clusters to the oxide support creates the localized charging states of the interface gold with the high feasibility for H2 activation and dissociation. © 2012 American Institute of Physics. Source

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