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991.
Hong X Wang D Yu R Yan H Sun Y He L Niu Z Peng Q Li Y 《Chemical communications (Cambridge, England)》2011,47(18):5160-5162
Ultrathin Au/Ag bimetallic nanowires with remarkable Coulomb blockade effects were synthesized using octadecylamine as both a solvent and a surfactant. It is believed that the growth mechanism of the Au/Ag bimetallic ultrathin nanowires includes the noble-metal-induced reduction, the oriented attachment and the wire-wire fusion. 相似文献
992.
The acquired pH-responsive and reversible enrichment of organic dyes from aqueous solutions by peroxide modified ultrathin nanosheets of anatase and TiO(2)(B) is illustrated in comparison with P25 and TiO(2)(B) nanowires. 相似文献
993.
Ceria and nickel-doped ceria necklace-like nanowires were synthesized by a facile, surfactant free method, through an unconventional assembly route. Homogeneous doping of lower-valent cations introduces elastic strain, resulting in extrinsic surface defects and higher catalytic performance in CO oxidization. 相似文献
994.
995.
Sun W Jia F Sun Z Zhang J Li Y Zhang X Yang B 《Langmuir : the ACS journal of surfaces and colloids》2011,27(13):8018-8026
A new concept for dealing with cracks in colloidal crystals has been proposed. We induce the cracks rather than eliminate them via templates that possess hydrophilic/hydrophobic patterns on the surface (surface energy patterns), leading the cracks to propagate along the predetermined lines. Colloidal crystal arrays with various kinds of element figures separated by cracks could be reproducibly fabricated. Diverse crack patterns other than common stripes have been observed, and the mechanism of these behaviors has been explored. The factors that influence the crack density have been investigated to ensure that the templates could function effectively. Moreover, we obtained microcrystal blocks with specific shapes, detached from the substrate. 相似文献
996.
Shijuan Liu Yanhua Wang Xun Yang Jingyang Jiang 《Research on Chemical Intermediates》2012,38(9):2471-2478
The promoting effect of ultrasound on the selective reduction of nitroarenes to N-arylhydroxylamines by use of Zn in an environmentally benign CO2–H2O system has been demonstrated. The yield of N-phenylhydroxylamine reaches 95 % when the reaction is carried out with a Zn-to-nitrobenzene molar ratio of 2.2 under ultrasound (40 kHz) at 25 °C and normal pressure of CO2 for 60 min. Application of ultrasound to the reaction has the advantages of higher yield of N-arylhydroxylamines, shorter reaction time, and consumption of less Zn. 相似文献
997.
He YF Nan ML Sun JM Meng ZJ Yue FG Zhao QC Yang XH Wang H 《Molecules (Basel, Switzerland)》2012,17(2):1278-1291
Rotundic acid (RA, 1), a natural compound, exhibits potent tumor cell growth inhibiting properties. To date there are no reports on derivatives of RA. Furthermore, the 28-COOH position of RA might make it unstable and induced serious gastrointestinal side effects when it was applied in vivo. Therefore, in order to explore and make use of this compound, eight new amino acid derivatives of RA at the 28-COOH position were synthesized and evaluated for their cytotoxicities in vitro on three tumor cell lines including A375, HepG2 and NCI-H446. As a result, a few of these new amino acid derivatives showed stronger cytotoxicity. Compound 5a was found to have the best inhibition activity on the three tested human tumor cell lines with IC(50) values of less than 10 μM compared with RA treatment. Meanwhile, the cytotoxicity of compound 6b was significantly higher than that of RA on the A375 cell line and almost the same as RA on the HepG2 and NCI-H446 cell lines. Hence, compounds 5a and 6b may serve as potential lead compounds for the development of new anti-tumor drugs. 相似文献
998.
Huang TT Huang YC Qing XY Xia Y Luo X Ye TH Yu LT 《Molecules (Basel, Switzerland)》2012,17(6):6317-6330
A novel series of N-methylpicolinamide-4-thiol derivatives were synthesized and evaluated on human cancer cell lines. Among them, compound 6p displayed potent and broad-spectrum anti-proliferative activities in vitro on some human cancer cell lines, even better than sorafenib. The advanced kinase inhibitory assays showed that compound 6p could selectively inhibit Aurora-B kinase. The biological results were rationalized by the molecular docking study, which indicated the stable interactions of 6p with the Aurora-B kinase. 相似文献
999.
(Ni(1-x),Mg(x))(3)Si(2)O(5)(OH)(4) solid-solution nanotubes (NTs) with tunable compositions were hydrothermally synthesized by altering the molar ratio of Mg(2+) to Ni(2+). The as-synthesized NTs were loaded with sub-0.06 wt % palladium (Pd; ~0.045 wt %) for Suzuki-Miyaura (SM) coupling reactions between iodobenzene or 4-iodotoluene and phenylboronic acid. The (Ni,Mg)(3)Si(2)O(5)(OH)(4) (Mg(2+):Ni(2+) = 1.0:1.0) NTs supported by 0.045 wt % Pd promoted the iodobenzene-participated coupling reaction with a high yield of >99%, an excellent recycling catalytic performance during 10 cycles of catalysis with yields of ~99%, and also an extremely low Pd releasing level of ~0.02 ppm. High-activity Pd and PdO clusters, multitudes of dislocations, and defects and terraces contained within the NTs should contribute to the (Ni,Mg)(3)Si(2)O(5)(OH)(4) (Mg(2+):Ni(2+) = 1.0:1.0) NTs supported by 0.045 wt % Pd as a robust, reusable, and high-efficiency catalyst for SM coupling reactions with an extremely low Pd releasing level. The present hydrothermally stable (Ni,Mg)(3)Si(2)O(5)(OH)(4) (Mg(2+):Ni(2+) = 1.0:1.0) solid-solution silicate NTs provided an ideal alternative tubular-structured support for noble- or transition-metal catalysts with low Pd loading, good recycling, and extremely low ppb levels of Pd release, which could also be extended to some other SM coupling reactions. 相似文献
1000.
Several years ago, in quantum mechanics, Davies proposed a method to calculate particle’s traveling time with the phase difference of wave function. The method is convenient for calculating the sojourn time inside a potential step and the tunneling time through a potential hill. We extend Davies’ non-relativistic calculation to relativistic quantum mechanics, with and without particle-antiparticle creation, using Klein–Gordon equation and Dirac Equation, for different forms of energy-momentum relation. The extension is successful only when the particle and antiparticle creation/annihilation effect is negligible. 相似文献