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81.
Considering for the potential application in tissue engineering, polyaniline (PANi) film was fabricated via a two-step route: a self-assembled monolayer of C6H5NHC3H6Si(OMe)3 was firstly formed on the single-crystal Si substrate; the conducting PANi film was then prepared through electroless surface polymerization of the aniline molecules on the aniline monolayer-bearing silane surface in an acidic aqueous solution. The formation of PANi film on Si surface was confirmed by characterizations of X-ray photoelectron spectroscope (XPS) and specular reflectance Fourier transform infrared (SR-FTIR) spectrum, etc. At last, the proliferation behaviors of PC-12 cells on the PANi film surface were studied by the [3-(4,5-dimethyldiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) colorimetric assays, acridine orange fluorometric staining, and scanning electron microscope (SEM) observation, etc. The results demonstrate that the as-prepared PANi film provides high ability for cell proliferation, exhibiting promising potentials as surface coating to cultivate neuronal cells for applications in the tissue engineering. 相似文献
82.
83.
Zeng-Qi Ou 《Journal of Mathematical Analysis and Applications》2004,291(1):203-213
An existence theorem of homoclinic solution is obtained for a class of the nonautonomous second order Hamiltonian systems , ∀t∈R, by the minimax methods in the critical point theory, specially, the generalized mountain pass theorem, where L(t) is unnecessary uniformly positively definite for all t∈R, and W(t,x) satisfies the superquadratic condition W(t,x)/|x|2→+∞ as |x|→∞ uniformly in t, and need not satisfy the global Ambrosetti-Rabinowitz condition. 相似文献
84.
核能的和平利用始于20世纪50年代,那时美国、前苏联等工业发达国家在进行核军备竞赛的同时,也竞相发展核电站.1954年,前苏联建成电功率为5千千瓦的试验性原子能电站,为世界上首座核电站;1957年,美国建成电功率为9万千瓦的希平港原型核电站;这些成就证明了利用核能发电的技术可行性.国际上把上述试验性和原型核电机组称为第一代核电机组. 相似文献
85.
It is well known that topology and dynamics are two major aspects to determine the function of a network. We study one of the dynamic properties of a network: trajectory convergence, i.e. how a system converges to its steady state. Using numerical and analytical methods, we show that in a logical-like dynamical model, the occurrence of convergent trajectory in a network depends mainly on the type of the fixed point and the ratio between activation and inhibition links. We analytically proof that this property is induced by the competition between two types of state transition structures in phase space: tree-like transition structure and star-like transition structure. We show that the biological networks, such as the cell cycle network in budding yeast, prefers the tree-like transition structures and suggest that this type of convergence trajectories may be universal. 相似文献
86.
A pair of enantiomers formulated as {Δ-cis-[Ni(en)2OAc][ClO4]} n (Δ-1) and {Λ-cis-[Ni(en)2OAc][ClO4]} n (Λ-1) (en = diaminoethane, OAc? = acetate anion) were obtained when nickel acetate was reacted with diaminoethane and sodium perchlorate in the absence of any chiral source, whereas the reactions of nickel acetate with 1,3-propanediamine and sodium perchlorate only gave a centrosymmetric complex [Ni(1,3-pn)2OAc][ClO4] (2) (1,3-pn = 1,3-propanediamine). Single-crystal X-ray diffraction analyses of all three complexes indicated that the central Ni(II) atoms all have a distorted octahedral coordination geometry, being coordinated by four nitrogen atoms of the diamine ligands, plus two oxygen atoms of OAc?. In complexes Δ-1 and Λ-1, the monomers of {Δ-cis-[Ni(en)2OAc]}+ and {Λ-cis-[Ni(en)2OAc]}+ are connected through intermolecular hydrogen bonds to generate one-dimensional right- and left-handed homochiral helical chains, respectively, while the monomers of [Ni(1,3-pn)2OAc]+ are linked by similar intermolecular hydrogen bonds to form one-dimensional zigzag chains instead of helical chains. The chiral natures of complexes Δ-1 and Λ-1 have been confirmed by circular dichroism spectroscopy. 相似文献
87.
Let n be a positive integer and let 0 < α < n. Consider the integral equation We prove that every positive regular solution u(x) is radially symmetric and monotone about some point and therefore assumes the form with some constant c = c(n, α) and for some t > 0 and x0 ? ?n. This solves an open problem posed by Lieb 12 . The technique we use is the method of moving planes in an integral form, which is quite different from those for differential equations. From the point of view of general methodology, this is another interesting part of the paper. Moreover, we show that the family of well‐known semilinear partial differential equations is equivalent to our integral equation (0.1), and we thus classify all the solutions of the PDEs. © 2005 Wiley Periodicals, Inc. 相似文献
88.
课堂教学中的心理健康教育,是指教师在教学过程中能自觉地、有意识地运用心理学理论和技术,启发学生的学习兴趣,帮助学生提高课堂学习的认知、情感与行为技能,促进学生生动、活泼、主动地学习和发展. 学校以教学为中心工作,而课堂教学又是学校工作的主要场所,也是实施素质教育的主要途径.长期以来,学生被动受教,身心发展 相似文献
89.
Preparation of cyclodextrin‐modified monolithic hybrid columns for the fast enantioseparation of hydroxy acids in capillary liquid chromatography 下载免费PDF全文
Kamila Szwed Junjie Ou Guang Huang Hui Lin Zhongshan Liu Hongwei Wang Hanfa Zou 《Journal of separation science》2016,39(6):1110-1117
Cyclodextrins and their derivatives are one of the most common and successful chiral selectors. However, there have been few publications about the use of cyclodextrin‐modified monoliths. In this study, organic hybrid monoliths were prepared by the immobilization of derivatized β‐cyclodextrin alone or with l‐ 2‐allylglycine hydrochloride to the polyhedral oligomeric silsesquioxane methacryl substituted monolith. The main topic of this study is a combined system with dual chiral selectors (l‐ 2‐allylglycine hydrochloride and β‐cyclodextrin) as monolithic chiral stationary phase. The effect of l‐ 2‐allylglycine hydrochloride concentration on enantioseparation was investigated. The enantioseparation of the four acidic compounds with resolutions up to 2.87 was achieved within 2.5 min on the prepared chiral monolithic column in capillary liquid chromatography. Moreover, the possible mechanism of enantioseparation was discussed. 相似文献
90.