Browsing by Author "Wang, YY"

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    Electrodeposition and characterization of thermoelectric Bi2Te2Se/Te multilayer nanowire arrays
    (Academic Press Ltd- Elsevier Science Ltd, 2011-11-01) Li, XL; Cai, KF; Yu, DH; Wang, YY
    Multilayer nanowire arrays of a new heterogeneous thermoelectric material, Bi(2)Te(2)Se/Te, were successfully fabricated by a template-assisted pulsed electrodeposition method. The nanowires were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, high resolution transmission electron microscopy, and energy dispersive X-ray spectroscopy, respectively. The diameter of the nanowires is in the range of 60-85 nm. By adjusting the concentration of Te precursor, the length of the Te segment can be modulated. At sufficient low concentration of Te precursor, the phase composition of the other segment can even be changed from Bi(2)Te(2)Se to Bi(2)Se(2)Te. The formation and growth mechanisms of the nanowires were proposed. (C) 2011 Elsevier Ltd.
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    A stable isotope approach to determine herbivorous diets of wintering geese at Dongting Lake, China
    (Beijing ICP, 2016-06) Guan, L; Mazumder, D; Yang, XX; Wen, L; Wang, YY; Lei, JL; Lei, GC
    The East Dongting Lake National Nature Reserve in China is listed as a Ramsar Wetlands due to its global significance for migratory waterbird conservation, especially for the geese. For example, more than 90% of East Asian population of the vulnerable Lesser White-fronted Goose(Anser erythropus), and large numbers of Bean Goose(Anser fabilis) and Greater White-fronted Goose(Anser albifrons) over winter here every year from October to the next March. However, the habitats and food quality of the wintering geese have been threatened by hydrological alternation due to the operation of the Three Gorges Dam. Understanding the diets of these geese is fundamental for their conservation. We used the stable isotopic ratios of the body tissues of three predominant goose species(i.e. Ans?er erythropus, Anser fabilis and Anser albifrons) and their potential diet items(6 grass species), and applied smooth transition autoregressive(SIAR) mixing models to quantify the contribution of different food items to their diets. The results showed that the δ13C values of the blood samples were significantly different from those of feather, and the difference was consistent for the three kinds of geese. These results indicated that clear dietary shifts from their breeding place at the Arctic to the wintering place at Dongting Lake. The δ13C values of the blood samples of the geese showed there were no significant difference(ANOVA, p=0.265) suggesting that they share the same food sources at Dongting Lake. Moreover, the multiple-source mixing models(i.e. SIAR model) indicated that no single plant had a contribution greater than 35% to the diet of geese at 0.95 confident levels(0.50 and 0.95 credibility intervals of the posterior distributions range from 0.24-0.25 and 0.32-0.34, respectively). The results indicated that the geese had no preference for a particular plant. The findings suggested that the features at patch level(e.g. vegetation greenness and development stage) but not plant species might be the decisive factor in the habitat selection of the geese. Therefore, the management actions aiming to maintain habitat quality were critical for the waterbird conservation in Dongting Lake. © Beijing ICP 2016
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    A stable isotope approach to determine herbivory diets of wintering geese at Dongting lake, China
    (University of New South Wales and Australian Nuclear Science and Technology Organisation, 2015-07-09) Guan, L; Mazumder, D; Yang, XX; Wen, L; Lei, JL; Wang, YY; Lei, GC
    Not provided to ANSTO Library.
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    Synthesis and thermoelectric properties of single crystalline and polycrystalline Ba8Ga16Ge30
    (Elsevier, 2010-02-18) Wang, HF; Cai, KF; Li, H; Yu, DH; Wang, XC; Zhou, CW; Li, XL; Wang, YY; An, BJ; Du, Y
    Large Ba8Ga16Ge30 single crystals were synthesized by a Ga-flux method. The single crystals were characterized by X-ray diffraction and energy-dispersive X-ray spectroscopy. The cubic structure of Ba filled type-I germanium clathrates with lattice parameter of 10.767 Å has been confirmed. The Ba8Ga16Ge30 polycrystalline sample was prepared by melting the synthesized single crystals. Thermoelectric properties of the single crystalline and polycrystalline Ba8Ga16Ge30 samples were measured from room temperature to 773 K. The single crystalline sample shows p-type conduction, while the polycrystalline sample exhibits n-type conduction and typical heavily doped semiconducting behavior. At room temperature, the electrical conductivity of the polycrystalline sample is much higher than that of the single crystalline sample, whereas the absolute value of Seebeck coefficient of the single crystalline sample is higher than that of the polycrystalline sample. The maximum power factor for the single crystalline and polycrystalline samples reaches ~17 μW cm−1 K−2 at 773 K and ~10 μW cm−1 K−2 at 500 K, respectively. © 2010, Elsevier Ltd.