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991.
Lin C Wang Y Lai Y Yang W Jiao F Zhang H Ye S Zhang Q 《Colloids and surfaces. B, Biointerfaces》2011,83(2):285-375
Biodegradable poly(lactic-co-glycolic acid) (PLGA)/carboxyl-functionalized multi-walled carbon nanotube (c-MWCNT) nanocomposites were successfully prepared via solvent casting technique. Rat bone marrow-derived mesenchymal stem cells (MSCs) were employed to assess the biocompatibility of the nanocomposites in vitro. Scanning electron microscopy (SEM) observations revealed that c-MWCNTs gave a better dispersion than unmodified MWCNTs in the PLGA matrix. Surface properties were determined by means of static contact angle, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) analysis. The presence of c-MWCNTs increased the mechanical properties of the nanocomposites. Seven-week period in vitro degradation test showed the addition of c-MWCNTs accelerated the hydrolytic degradation of PLGA. In addition, SEM proved that the cells could adhere to and spread on films via cytoplasmic processes. Compared with control groups, MSCs cultured onto PLGA/c-MWCNT nanocomposites exhibited better adhesion and viability and also displayed significantly higher production levels of alkaline phosphatase (ALP) over 21 days culture. These results demonstrated that c-MWCNTs modified PLGA films were beneficial for promoting cell growth and inducing MSCs to differentiate into osteoblasts. This work presented here had potential applications in the development of 3-D scaffolds for bone tissue engineering. 相似文献
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Jingsong Sun Lin Liang Jianmin Sun Yanqiu Jiang Kaifeng Lin Xianzhu Xu Runwei Wang 《Catalysis Surveys from Asia》2011,15(1):49-54
This short review presents the recent developments in the direct synthesis of cyclic carbonates from olefins and CO2. The straightforward synthesis of cyclic carbonates from olefins instead of epoxides, also called one-pot “oxidative carboxylation”
of olefins, can be viewed as the coupling of two sequential reactions of epoxidation of olefins and CO2 cycloaddition to epoxides formed. The facile synthetic approach would make carbonate synthesis simpler and even cheaper with
industrial potential from environmental and economic points of view. Some progresses have been made on this direct synthetic
reaction for cyclic carbonates with homogeneous and heterogeneous catalysts, however, this reaction system is still at a preliminary
stage. Among the catalysts reported, only a few can be considered as effective for the direct oxidative carboxylation of olefins
to cyclic carbonates. Thus active and selective catalysts should be explored to put the direct synthesis of cyclic carbonates
into practical applications. 相似文献
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Journal of Nanoparticle Research - The demand for metal nanoparticles is increasing strongly. Transferred arc synthesis is a promising process in this respect, as it shows high production rates,... 相似文献
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Wing Chi Yu Shi-Jian Gu Hai-Qing Lin 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(10):212
Without any knowledge of the symmetry existing in a system, we derive the exact forms of the order parameters which show long-range correlations in the ground state of the one-dimensional (1D) extended Hubbard model using a quantum information approach. Our work demonstrates that the quantum information approach can help us to find the explicit form of the order parameter, which could not be derived systematically via traditional methods in the condensed matter theory. 相似文献
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