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61.
Cuiling Du Dr. Jie Zhao Dr. Jinbo Fei Dr. Liang Gao Wei Cui Dr. Yang Yang Prof. Dr. Junbai Li 《化学:亚洲杂志》2013,8(4):736-742
A reactive template method was used to fabricate alginate‐based hydrogel microcapsules. The uniform and well‐dispersed hydrogel capsules have a high drug loading capacity. After they are coated by a folate‐linked lipid mixture on the surface, the capsules possess higher cell uptake efficiency by the molecule recognition between folate and the folate‐receptor overexpressed by the cancer cells. Moreover, in this bioconjugate, the lipid could remarkably reduce the release rate of hydrophilic doxorubicin from the hydrogel microcapsules and encapsulate the hydrophobic photosensitizer hypocrellin B. The biointerfaced capsules could be used as drug carriers for combined treatment against cancer cell proliferation in vitro; this was much more effective than chemotherapy or photodynamic therapy alone. 相似文献
62.
63.
The Knoevenagel condensation of Meldrum's acid with aromatic aldehydes proceeded efficiently in a reusable ionic liquid, ethylammonium nitrate, at room temperature in the absence of any catalyst with high yields. 相似文献
64.
A practical protocol was disclosed for the nickel-catalyzed C-alkylation of 9-fluorenone hydrazone with alcohols using t-BuOK as the base, and 9-monoalkylated fluorene derivatives were obtained in good yields under the benign conditions. 相似文献
65.
Molecular oxygen (1 atm) conveniently reacts with olefins in the presence of simple supported metal heterogeneous catalysts and aldehydes (e.g., isobutyraldehyde and benzaldehyde) at room temperature to give epoxides in good yields. 相似文献
66.
In the presence of 1,8-diazabicycolo[5.4.0]undec-7-ene (DBU) and concentrated H2SO4, 2-naphthol reacted smoothly with α,β-unsaturated trifluoromethyl ketones in CH2Cl2 at room temperature, affording the 3-trifluoromethyl-substituted benzo[f]chromene derivatives in good to excellent yields in a one-pot reaction. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details]. 相似文献
67.
Ya Gao Nan Chen Weiwu Hu Chuanping Feng Baogang Zhang Qian Ning Bin Xu 《Journal of solution chemistry》2013,42(4):691-704
Adsorption is an effective treatment process for removing phosphorus and thus controlling eutrophication. In this study, a clay composite material called Al–dolomite–montmorillonite (Al–DM) was prepared and characterized. Al–DM performed well with respect to phosphate removal, with its performance depending on the Al–DM loading, contact time, initial phosphorus concentration and initial solution pH. Adsorption mechanisms were investigated by conducting batch tests on phosphate adsorption using the Al–DM. The adsorption process fitted both the pseudo-second-order kinetics model and the intra-particle diffusion model. The Langmuir, Freundlich and BET models all adequately described the adsorption isotherm data. Thermodynamic studies showed that the adsorption process was endothermic and spontaneous in nature. Al–DM is an effective adsorbent for phosphate removal mainly due to its hierarchical porous structures as shown by characterization with SEM and EDS. Chemical changes occurring before and after adsorption in a water environment indicated that Al–DM had little negative effect on water quality. 相似文献
68.
Hybrid materials based on polymethylphenylsiloxane (PMPS) and organic functionalized silica were synthesized via condensation reaction between silanol and alkoxysilyl groups in the presence of quaternary ammonium hydroxide. The structure of prepared materials was investigated by FTIR and NMR, which indicate that the products have incorporated modified silica into the polymer matrix. The prepared hybrid materials show a satisfactory thermal resistance because the initial decomposition of typical product occurred at nearly 100 K higher than that of the pure polymer according to the thermogravimetric analysis (TGA) results. Differential thermogravimetric analysis (DTGA) data confirm that the thermal degradation of prepared hybrid materials comprises of two steps, of which the first one could be controlled by adjusting the content of silica particles and the ratio of surface groups on the particles. The coating films obtained from hybrid products exhibit good thermal mechanical properties. Therefore, the materials are hoped to be used for the application in thermal resistant coating. 相似文献
69.
The rear film compensated reflective twisted nematic liquid crystal display device was studied in normally black and normally white operation conditions using a dynamic parameter space method. The electro-optical responses and reflectance spectra were also studied for different operation modes. A comparison was made between rear film and front film compensated reflective twisted nematic liquid crystal displays. We show that high quality normally white or normally black modes can be obtained by placing the fast axis of a quarter wave plate at 45° or 0° to the input director direction. The viewing angle characteristics of the optimum modes were also studied. 相似文献
70.
Yashao Chen Jinhong Yi Qiang Gao Xiaoling Zhou Yanling Luo Peng Liu 《Plasma Chemistry and Plasma Processing》2013,33(6):1153-1165
To improve the biocompatibility of poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) film, a technique based on Ar plasma pretreatment and UV-induced grafting polymerization was used to immobilize carboxymethyl chitosan (CMCS) on the FEP film surfaces. Initially Ar plasma was used to treat FEP film. Then, plasma treated FEP film was modified via UV-induced grafting polymerization with hydrophilic acrylic acid (AAc) monomer. The following immobilization of CMCS on the FEP-pAAc surface was carried out via an amidation reaction. The change of chemical composition and surface morphology of FEP film were characterized by attenuated total reflectance Fourier transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electronic microscopy (SEM) and atomic force microscopy (AFM). Results of water contact angles measurement showed that the hydrophilicity of the surface has improved significantly after surface modification. Furthermore, methyl thiazolyl tetrazolium (MTT) assay and cell morphology analysis confirmed that mouse fibroblasts (L929 cells) attachment and proliferation were improved remarkably on the modified FEP surface. These results suggest that CMCS were successfully employed to surface engineering FEP film, and enhanced its cell biocompatibility. The approach presented here may be exploited for surface modification of biomaterials. 相似文献