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991.
Benjamin Leung Qian Sun Christopher Yerino Yu Zhang Jung Han Bo Hyun Kong Hyung Koun Cho Kuan-Yung Liao Yun-Li Li 《Journal of Crystal Growth》2012,341(1):27-33
Semipolar (112?2) GaN was grown on stripe etched r-plane sapphire substrate by a maskless selective growth method. The initial stage of growth is analyzed by describing the competitive nucleation mechanisms, due to the interplay between kinetics and energetics, on disparate crystallographic planes within the diffusion length of adatoms. The microstructure of the final coalesced semipolar GaN film is revealed by x-ray rocking curve (XRC) analysis and transmission electron microscopy (TEM). XRC analysis yields linewidths between 280 and 550 arcsec for all on-axis and off-axis diffractions. Linewidth broadening factors in dislocated crystals are considered, and a large reduction of stacking fault density can be seen from the measured linewidths as fit to this model. TEM shows a change in the defect characteristics as compared to conventional growth on m-sapphire, filtering of stacking faults and confirmation of the low dislocation density of the final GaN film. The microstructural quality of the film substantiates the possibility of using an inclined basal-plane growth to synthesize non-basal-plane active devices, thus removing the rigid restrictions in contemporary GaN nonpolar and semipolar heteroepitaxy. 相似文献
992.
Chao WS Liao KH Chen CT Huang WK Lan CM Diau EW 《Chemical communications (Cambridge, England)》2012,48(40):4884-4886
Hybrids based on a dibenzosuberene core bearing a spiro-fluorene junction at the C-5 position and with amino donor and β-thiophenyl-α-cyanoacrylic acid acceptor groups at C-3 and C-7, respectively, serve as new organic sensitizer materials for solar cell applications. Solar cell devices based on these materials show a conversion efficiency (η) of up to 6.1% (V(oc) = 697 mV, J(sc) = 12.2 mA cm(-2), FF = 0.72) under AM 1.5 G conditions. The best IPCE values exceed 75% within the 450-550 nm absorption range. 相似文献
993.
Y Li Y Jiang M Chen H Liao R Huang Z Zhou N Tian S Chen S Sun 《Chemical communications (Cambridge, England)》2012,48(76):9531-9533
Trapezohedral Pt nanocrystals enclosed by 24 high-index {522} facets have been successfully prepared for the first time in high yield by a direct square wave electrodeposition method. They exhibit a significantly enhanced catalytic activity for C-1 molecules (CO, CH(3)OH, HCOOH). 相似文献
994.
Fu Z Zeng Y Liu X Song D Liao S Dai J 《Chemical communications (Cambridge, England)》2012,48(49):6154-6156
Keggin polyphosphotungstate cluster was captured by a porous molecular ring with light sensitizing TPT molecules as connectors and copper ions as nodes. The self-assembly reaction gives a stable host-guest supramolecular system, demonstrating efficient heterogeneous photocatalytic behavior for the degradation of methyl orange in near-neutral conditions. 相似文献
995.
Y Zeng Z Fu H Chen C Liu S Liao J Dai 《Chemical communications (Cambridge, England)》2012,48(65):8114-8116
A new type of electron transfer (ET) system was built via the combination of a highly stable MOF host framework and methyl viologen guest molecule. The π-stacking arrangements adjust the distance between the D-A components, contributing to the formation of an ultra long-lived charge separated state in the photo/thermo dual stimuli-responsive complex. 相似文献
996.
Application of 2,3-naphthalenediamine in labeling natural carbohydrates for capillary electrophoresis 总被引:1,自引:0,他引:1
Kuo CY Wang SH Lin C Liao SK Hung WT Fang JM Yang WB 《Molecules (Basel, Switzerland)》2012,17(6):7387-7400
Neutral and acidic monosaccharide components in Ganoderma lucidum polysaccharide are readily labeled with 2,3-naphthalenediamine, and the resulting saccharide-naphthimidazole (NAIM) derivatives are quantified by capillary electrophoresis (CE) in borate buffer. Using sulfated-α-cyclodextrin as the chiral selector, enantiomers of monosaccharide-NAIMs are resolved on CE in phosphate buffer, allowing a simultaneous determination of the absolute configuration and sugar composition in the mucilage polysaccharide of a medicinal herb Dendrobium huoshanense. Together with the specific enzymatic reactions of various glycoside hydrolases on the NAIM derivatives of glycans, the structures of natural glycans can be deduced from the digestion products identified by CE analysis. Though heparin dissachrides could be successfully derived with the NAIM-labeling method, the heparin derivatives with the same degree of sulfation could not be separated by CE. 相似文献
997.
Lycoris species have been known since long ago as a multi-utility ethnomedicinal herbal in China. It has been reported to exhibit a number of properties such as anticancer, neuroprotective, and antibacterial activities. In the present study, the anticancer efficacy of dichloromethane extracts of Lycoris aurea (DELA), was evaluated both in vivo and in vitro using murine sarcoma 180 cells. To evaluate the effects of DELA on apoptotic cell death, flow cytometry and Western blotting were performed. DELA demonstrated promising inhibition effects on sarcoma 180 cells in vitro and a 53.49% inhibitory rate on cancer cells in vivo. DELA treatment increased thymus indices and spleen indices in vivo, indicating that it reduced tumours, but did not damage the main immune organs. The DELA-evoked increase in apoptotic cell death was accompanied by occurrence of cleaved caspase-3 and decreases in the ratio of Bcl-2/Bax. Further purification and LCMS analysis showed DELA contained homolycorine, 2α-hydroxyoduline, oduline, hippeastrine, 2α-hydroxy-6-O- methyloduline, and 2α-methoxy-6-O-methyloduline. These results indicate that DELA exerted its anticancer effects, at least in part, by inducing cancer cell apoptosis and thus can be considered as a potential candidate agent for treatment of cancer. 相似文献
998.
Chiral tris(oxazoline)/Cu(I) complexes are demonstrated as a type of efficient catalysts for the asymmetric Kinugasa reaction of terminal alkynes with C-arylnitrones, providing a highly enantio- and diastereoselective access to optically active β-lactams. 相似文献
999.
Hong‐Lin Liao Zhi‐Zhong Sun Han‐Sheng Shi Ting‐Chun Wang 《Numerical Methods for Partial Differential Equations》2012,28(5):1598-1619
A compact ADI scheme of second‐order in time and fourth‐order in space is proposed for solving linear Schrödinger equations with periodic boundary conditions. By using the recently suggested discrete energy method, it is shown that the stable compact ADI method is unconditionally convergent in the maximum norm. Numerical experiments, including the comparisons with the second‐order ADI scheme and the time‐splitting Fourier pseudospectral method, are presented to support the theoretical results and show the effectiveness of our method. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2012 相似文献
1000.
The effects of intermodal dispersion on ultrashort optical pulse propagation through multi-core fibers are analyzed theoretically,
which has been ignored in previous studies. A three-core fiber with collinear and triangular configuration and a four-core
fiber are considered. We demonstrate with numerical examples that the intermodal dispersion can cause pulse breakup effect
in multi-core fibers. 相似文献