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81.
Yin YingZhuo Chai Hai-Feng WangPeng Li Chang-Wu ZhengGang Zhao Yue-Peng Cai 《Tetrahedron》2011,67(19):3337-3342
A highly enantioselective [4+2] cycloaddition reaction of β,γ-unsaturated α-keto esters with oxazolones was realized with readily available cinchona alkaloids as the catalysts. Using this reaction, a series of highly functionalized δ-lactones with adjacent α-quaternary-β-tertiary stereocenters were obtained in high yields (up to 97%) and with good-to-excellent enantioselectivities (up to 97% ee). 相似文献
82.
Paul H. Bernardo Jasmeet K. KhanijouTze Hau Lam Joo Chuan Tong Christina L.L. Chai 《Tetrahedron letters》2011,52(1):92-94
A series of 8-anilino and 9-anilinophenanthridine-7,10-diones was prepared and screened against various cancer cell lines to measure anti-proliferative activity. The compounds tested display potent cytotoxic activity in the micromolar and sub-micromolar range. These compounds are promising new leads for developing anticancer compounds. 相似文献
83.
Jin-Ling Chai Yu-Tong Wu Xun-Qiang Li Bao Yang Jian-Jun Lu 《Journal of solution chemistry》2011,40(11):1889-1898
An α–ε–β fish-like phase diagram of three phase microemulsions was proposed and used to investigate the phase behavior of the microemulsion
systems sodium dodecyl sulfate (SDS)/alcohol/oil/water at various oil/water ratios. Related physicochemical properties of
the microemulsion systems were calculated. As the oil/water mass ratio increases, the solubility (ε
B) of the alcohol increases, while both the mass fraction of alcohol in the interfacial layer (A
S) and the solubilization ability (SP
∗) decrease. The effect of oils on the properties of the microemulsion systems was investigated. 相似文献
84.
Synergetic effect between sulfurized Mo/γ-Al_2O_3 and Ni/γ-Al_2O_3 catalysts in hydrodenitrogenation of quinoline 下载免费PDF全文
An evidence for the synergetic effect between the stacked bed of Mo/γ-Al2O3 and Ni/γ-Al2O3 in the hydrodenitrogenation (HDN) reaction of quinoline has been provided in this paper. The synergism factor decreases when the reaction temperature increases (280?340 ?C). The synergetic effect leads to improve the hydrogenation activity for the stacked bed compared with the single Mo/γ-Al2O3 bed, which may be attributed to the generation of hydrogen spillover on the Ni/γ-Al2O3 catalyst. 相似文献
85.
The paper describes the use of crack-opening interferometry for examining the variation in normal crack-opening displacements
(NCOD) along the front of an interfacial crack in an edge-cracked bimaterial strip under biaxial loading. For the glass/epoxy
combination considered here, the crack front was concave in the direction of crack growth, in contrast to previous observations
with a glass/polyurethane/glass sandwich specimen and cracks in homogeneous materials. The NCOD were greatest in the interior
of the specimen for all mode-mixes considered and the exponents in a power-law fit of NCOD versus distance from the crack
front decreased towards the free surface. The exponents varied with mode-mix, suggesting that interfacial crack-front geometries
could be similarly affected. 相似文献
86.
研究了不同脉冲次数强流脉冲电子束表面改性对CuFe10合金组织及性能的影响。强流脉冲电子束处理CuFe10合金的重熔表面出现了火山坑和直径为100nm到1μm的富铁球,表明了强流脉冲电子束处理CuFe10合金表面发生了液相分离。强流脉冲电子束脉冲轰击30次后,CuFe10合金表面的显微硬度与耐蚀性能均得到显著改善,主要是由于强流脉冲电子束轰击处理CuFe10合金表层引发的快速熔凝过程中表面发生了液相分离及晶粒细化的缘故。 相似文献
87.
Jing Li Wenduo Chen Rui Lin Meirong Huang Min Wang Maosheng Chai Hongwei Zhu 《Particle & Particle Systems Characterization》2021,38(11):2100148
CO2 reduction reaction (CO2RR) has indispensable significance for carbon recycling and renewable energy production. As typical electrochemical catalysts, Au and Ag show relatively high reaction activity and selectivity in CO2RR. In this study, a series of Ag–Au bimetallic catalysts are designed and synthesized through the thermal evaporation method for efficient yet massive production of electrochemical catalysts. The Ag–Au catalysts show significantly enhanced activity and selectivity in CO2RR, which is mainly attributed to the increased grain boundaries with well-dispersed single Ag atoms. After the optimization, Au20Ag10 exhibits the best performance with a CO Faraday efficiency of 89% at −0.9 V (vs the reversible hydrogen electrode) with good stability. 相似文献
88.
Chen Chen Xiangheng Niu Yan Chai Hongli Zhao Minbo Lan Yonggang Zhu Gang Wei 《Electroanalysis》2013,25(6):1446-1452
This work presents a disposable bismuth‐antimony film electrode fabricated on screen‐printed electrode (SPE) substrates for lead(II) determination. This bismuth‐antimony film screen‐printed electrode (Bi‐SbSPE) is simply prepared by simultaneously in situ depositing bismuth(III) and antimony(III) with analytes on the homemade SPE. The Bi‐SbSPE can provide an enhanced electrochemical stripping signal for lead(II) compared to bismuth film screen‐printed electrodes (BiSPE), antimony film screen‐printed electrodes (SbSPE) and bismuth‐antimony film glassy carbon electrodes (Bi‐SbGC). Under optimized conditions, the Bi‐SbSPE exhibits attractive linear responses towards lead(II) with a detection limit of 0.07 µg/L. The Bi‐SbSPE has been demonstrated successfully to detect lead in river water sample. 相似文献
89.
Jen‐Taut Yeh Chi‐Hui Tsou Wei Lu Ya‐Ming Li Han Wen Xiao Chi‐Yuan Huang Kan‐Nan Chen Chin‐San Wu Wan‐Lan Chai 《Journal of Polymer Science.Polymer Physics》2010,48(9):913-920
Fourier transform infrared and nuclear magnetic resonance results suggest that the carboxylic acid groups of poly(lactic acid) (PLA) molecules react with the hydroxyl groups of FePol (FP) molecules during the melt‐blending of PLAxFPy specimens. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) experiments of PLA and PLA/FP specimens suggest that only small amounts of poor PLA and/or FP crystals are present in their corresponding melt crystallized specimens. In fact, the percentage crystallinity, peak melting temperature, and onset re‐crystallization temperature values of PLA/FP specimens reduce gradually as their FP contents increase. However, the glass transition temperatures of PLA molecules found by DSC and DMA reduce to a minimum value as the FP contents of PLAxFPy specimens reach 6 wt %. Further DMA and morphological analysis of PLA/FP specimens reveal that FP molecules are compatible with PLA molecules at FP contents equal to or less than 6 wt %, as no distinguished phase‐separated FP droplets and tan δ transitions were found on fracture surfaces and tan δ curves of PLA/FP specimens, respectively. In contrast to PLA, the FP specimen exhibits highly deformable and tearing properties. After blending proper amounts of FP in PLA, the inherent brittle deformation and poor tearing behavior of PLA were successfully improved. Possible reasons accounting for these interesting crystallization, compatible and tearing properties of PLA/FP specimens are proposed. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 913–920, 2010 相似文献
90.
Disulfides have been synthesized by oxidation of thiols using air as oxidant catalyzed by Co-Salophen with high yields,mild and neutral conditions,and easy procedures of the catalyst.The products were confirmed by ~1H NMR and IR. 相似文献