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91.
研究了黄素腺嘌呤二核苷酸(FAD)在热石墨柱电极上的电化学行为.发现对吸附有FAD的电极加热同时进行循环伏安扫描,随电极温度升高,氧化还原峰电位负移,峰电流减小,峰形变差.采用方波伏安进行吸附溶出分析,如果只在吸附步骤对电极加热,室温溶出,则随电极温度升高,溶出峰电流显著增加.这主要归因于直接对电极加热引起的强制热对流,这种对流能提高传质,促进吸附,增强溶出响应.5 min预富集对电极加热到72 ℃,检出限可以达到1×10-8 mol/L(S/N=3),比室温27 ℃时降低了一个多数量级,相应灵敏度也明显提高. 相似文献
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Huang Wei Sun Piao-Yang Fang Jiang-Lin Sun Yue-Fei Gou Shao-Hua 《Transition Metal Chemistry》2003,28(8):925-929
A novel
3-CO3
2– bridging trinuclear copper(II) complex, formulated as {[Cu3(2,2-bpy)6(
3-CO3)]2(ClO4)8 · H2O} (3), has been synthesized by fixation of atmospheric CO2. The X-ray single crystal determination of (3) reveals that each CuII center is penta-coordinated by two 2,2-bipyridine molecules and one oxygen atom of the
3-carbonato anion forming a distorted pyramid. 相似文献
94.
0IntroductionAsweknow,camphoricderivativespossessingtwochiralcarbonatomsintheirmoleculesoccupyalargebranchoforganiccompoundsandhavebeenusedwidelyinorganicsynthesis.D鄄,L鄄andD,L鄄1,2,2鄄trimethylcyclopentane鄄1,3鄄diaminesareveryusefulintermediatesinorgan 相似文献
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LIU Jin XIANG Shao-Hua CUI Hui-Ping LI Jian 《理论物理通讯》2009,51(4):637-640
We study the time evolution of two two-state systems (two qubits) initially in the pure entangled states or the maximally entangled mixed states interacting with the individual environmental noise. It is shown that due to environment noise, all quantum entangled states are very fragile and become a classical mixed state in a short-time limit. But the environment can affect entanglement in very different ways. The type of decoherence process for certain entangled states belongs to amplitude damping, while the others belong to dephasing decoherenee. 相似文献
99.
We propose a simple scheme to not only generate GHZ states and W states of the multiparticle but also form a new category of multiparticle entangled states by letting the λ-type three-level atoms simultaneously interacting with a coherent cavity field followed by the selective measurements on the cavity mode. We investigate the influence of the cavity dissipation on the generated entangled state and discuss the experimental feasibility of our scheme. It is shown that the intensity of the coherent cavity field plays an instructive role in contribution to state preparation process while the cavity decay and the detuning between the atoms and cavity mode result in the deterioration of the generated entangled state. 相似文献
100.
Jian Zhu Shao-Hua Wang Zhen-Feng Bian Chen-Ling Cai He-Xing Li 《Research on Chemical Intermediates》2009,35(6-7):769-777
The hierarchical flower-like TiO2 has been achieved by using a simple solvothermal process without any surfactants or colloidal crystals as a template. The structures of the products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen adsorption–desorption analysis. The relationship between hierarchical structure and photocatalytic performance has been presented based on detailed characterizations. It was found that the hierarchical flower-like structure was a benefit for light absorption and significantly enhanced the photocatalytic activity. 相似文献