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961.
962.
Lixin Zhang W.E. McMahon Y. Liu Y. Cai M.H. Xie N. Wang S.B. Zhang 《Surface science》2012,606(21-22):1728-1738
The lattice-misfit InN/GaN (0001) interface supports a triangular network of α-core 90° partial misfit dislocations. These misfit dislocations provide excellent strain relief. However, in their unreconstructed form the dislocation contains numerous high-energy N dangling bonds, which must be eliminated by reconstructing the dislocation core. Existing single-period (SP) and double-period (DP) dislocation reconstruction models eliminate these dangling bonds via a like-atom dimerization, such as N-N dimers. However, we show that these N–N dimers are unstable for the III-N materials, so an entirely new reconstruction mechanism is needed. A “triple-period” (TP) structural model is developed which eliminates N dangling bonds via the formation of N vacancies instead of N-N dimers. The model contains no N–N (or III–III) bonds, fully bonds all N atoms to four group-III neighboring atoms, and satisfies the “electron counting rule” by transferring charge from In dangling bonds to Ga dangling bonds. 相似文献
963.
964.
Liang Zhong Kun Cui Peng Xie Jian‐Zhuang Chen Zhi Ma 《Journal of polymer science. Part A, Polymer chemistry》2010,48(7):1617-1621
A new titanium (IV) complex bearing phenoxyimine‐fluorene ligand was prepared and its behaviors in ethylene homo‐ and copolymerization with 1‐hexene, 1‐octene, and norbornene in the presence of modified methylaluminoxane (MMAO) were studied respectively. The effects of various polymerization conditions including polymerization temperature, ethylene pressure and the concentration of comonomer on the catalytic activities and properties of the resultant polymer were investigated. The broad molecular weight distribution of resulting polymer indicated that the multiple active species were formed during polymerization. Such complex showed good catalytic activities in ethylene homo‐ and copolymerizations and good capabilities of incorporating various comonomers into polyethylene backbone. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1617–1621, 2010 相似文献
965.
Zuzhen Zhao Xiang Fang Yongliang Li Yi Wang Pei Kang Shen Fangyan Xie Xin Zhang 《Electrochemistry communications》2009,11(2):290-293
The Pt supported on WC modified MWCNT catalysts (PtWC/MWCNT) were synthesized by the combination of organic colloidal and intermittent microwave heating (IMH) methods for the first. The results proved the better performance of the PtWC/MWCNT catalyst than that of Pt/C for methanol oxidation in terms of the onset potential and peak current density. The synergistic effect between Pt nanoparticles and WC and the structure effect of the MWCNTs could be the reasons to result in the high activity. The CO stripping test provided the evidence that the onset potential shift for methanol oxidation is consistent with the reduction in the overpotential for the CO oxidation on PtWC/MWCNT catalyst. Therefore, the mechanism of the high performance for methanol oxidation on PtWC/MWCNT catalyst is probably the easier oxidation of CO-like species which cause high overpotential for further oxidation of methanol. 相似文献
966.
ON MULTILINEAR COMMUTATORS OF Θ-TYPE CALDERóN-ZYGMUND OPERATORS 总被引:2,自引:1,他引:1
In this paper, we discuss the multilinear commutator of θ-type Calderón- Zygmund operators, and obtain that this kind of multilinear commutators is bounded from Lp(Rn) to Lq(Rn), from Lp(Rn) to Triebel-Lizorkin spaces and on certain Hardy type spaces. 相似文献
967.
The purpose of this paper is to characterize the pointwise rate of convergence for the combinations of Szász-Mirakjan operators using Ditzian-Totik modulus of smoothness. 相似文献
968.
用多孔玻璃膜管悬浮聚合法制备单分散性聚苯乙烯微球 总被引:7,自引:3,他引:4
Monodisperse polystyrene microspheres are prepared by shell porous glass(SPG)-suspension polymerization. The influences of SPG on size and size dispersity of the microspheres are investigated. The properties of the microspheres are studied by GPC, TEM and SEM. The results indicate that the polystyrene microspheres possess definite monodispersibity and their particle size is in the range of 5~12μm. 相似文献
969.
Xiaoying Xie Wenwen Liu Luyang Zhao Chengde Huang 《Journal of Solid State Electrochemistry》2010,14(9):1585-1594
Manganese–vanadium oxide had been synthesized by a novel simple precipitation technique. Scanning electron microscopy, X-ray
diffraction, Brunauer–Emmett–Teller, thermogravimetric analysis/differential scanning calorimetry, and X-ray photoelectron
spectroscopy were used to characterize Mn–V binary oxide and δ-MnO2. Electrochemical capacitive behavior of the synthesized Mn–V binary oxide and δ-MnO2 was investigated by cyclic voltammetry, galvanostic charge–discharge curve, and electrochemical impedance spectroscope methods.
The results showed that, by introducing V into δ-MnO2, the specific surface area of the mixed oxide increased due to a formation of small grain size. The specific capacitance
increased from 166 F g−1 estimated for MnO2 to 251 F g−1 for Mn–V binary oxide, and the applied potential window extended to −0.2–1.0 V (vs. saturated calomel electrode). Through
analysis, it is suggested that the capacitance performance of Mn–V binary oxide materials may be improved by changing the
following three factors: (1) small grain and particle size and large activity surface area, (2) appropriate amount of lattice
water, and (3) chemical state on the surface of MnO2 material. 相似文献
970.
Yuli Xie Yidong Liu Alison Rinderspacher Donald W. Landry 《Tetrahedron letters》2008,49(14):2320-2323
An efficient synthesis of a series of N-8-quinolinyl benzenesultams as novel NF-κB inhibitors was described via diazotization-induced cyclization of easily accessible N-8-quinolinyl-2-aminobenzenesulfonamides. 相似文献