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991.
Satoshi Someya Satoshi Yoshida Koji Okamoto Yan Rong Li Manabu Tange Mohammad Mezbah Uddin 《显形杂志》2010,13(1):41-47
Abstract
Droplets impinging on a hot surface that is near the Leidenfrost temperature were experimentally investigated. Ejection of jets from the top of the droplet was observed during the transient interaction between the droplet and a hot wall. We term this phenomenon jet ejection from droplets. When the bottom of the droplet initially impacts the hot surface, a jet is to be ejected from the top of the droplet. The jet ejection occurred only at low impact velocities and around the wetting limit temperature. It was not observed when droplets were dropped from large heights or when the surface was at a high temperature. 相似文献992.
<正>A new 5-O-(β-D-glucopyranosyl)-6'-O-benzoyl-2,5-dihydroxybenzoic acid was isolated from the ethyl acetate extract from the whole plants of Trifolium lupinaster L.Its structure was determined and deduced on the basis of their spectral data. 相似文献
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ZHANG Jin-lei TAN Xue-cai ZHAO Dan-dan TAN Sheng-wei HUANG Zeng-wei MI Yan HUANG Zai-yin 《高等学校化学研究》2010,26(4):541-545
<正>A novel third-generation hydrogen peroxide(H_2O_2) biosensor(Hb/CdS/MWNTs/GCE) was fabricated through hemoglobin(Hb) adsorbed onto the mercaptoacetic acid modified CdS QDs/carboxyl multiwall carbon nanotubes'(MWNTs) films.Cyclic voltammogram of Hb/CdS/MWNTs/GCE showed a pair of well-defined and quasi-reversible redox peaks with a formal potential(E~0) of-0.230 V(vs.Ag/AgCl) in 0.1 mol/L pH=8.0 phosphate buffer solution(PBS),which was the characteristic of the Hb heme Fe(Ⅲ)/Fe(Ⅱ) redox couple.The biosensor shows an excellent electrocatalytic activity to the reduction of H_2O_2.The response time of the designed biosensor to H_2O_2 at a potential of -0.30 V was less than 2 s and linear relationships were obtained in the concentration ranges of 2.0×10~(-6)—2.7×10~(-3) mol/L and 2.7×10~(-3)—7.7×10~(-3) mol/L with a detection limit of 3.0×10~(-7)mol/L(S/N=3).The apparent Michaelis-Menten constant K_m was estimated to be 1.324 mmol/L that illustrated the excellent biological activity of the fixed Hb. 相似文献
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Bis(imino)pyridine palladium(II) complexes 3 and 4 of type [PdCl(L)PF6] are found to be efficient catalysts for Suzuki–Miyaura reactions of aryl halides and arylboronic acids. The reactions proceed smoothly to generate the corresponding biaryl compounds in moderate to excellent yields. The synthesis of various fluorinated biphenyl derivatives was successfully achieved by the complex 4 catalyzed the Suzuki–Miyaura reaction in the presence of surfactants bearing a long alkyl chain. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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