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61.
综述了目前存在的微乳液制备方法、微观结构模型和形成理论,以及它在制备纳米复合材料方面的应用,并对微乳液法制备纳米材料的方法、影响因素及控制机理以及表征方法进行了归纳与总结.  相似文献   
62.
为避免传统的湿化学法制备有机一金属纳米掺杂复合材料中热处理给材料性能带来的不良影响,提出了一种新的工艺方法.室温下制备出有机-金属包覆掺杂型三元系复合材料体系.实现了染料分子对金属纳米粒子完全意义上包覆的设想.用电镜(TEM)观测了复合材料样品的显微结构,并对其UV—Vis吸收光谱进行了测量,给出了该包覆掺杂型材料的结构模型,并用所给模型成功地分析了实验结果产生的机理、  相似文献   
63.
以TiCl4为原料,采用胶溶法制备出了具有金红石结构的纳米针状TiO2粉体,该针形晶体长约180nm,直径约30nm,讨论了反应时间、反应温度对TiO2粒子形貌的影响,并采用TEM和XRD等方法对晶体进行了表征。  相似文献   
64.
改性纳米二氧化硅用于丙烯酸聚氨酯防腐涂料   总被引:4,自引:0,他引:4  
为改善纳米二氧化硅的分散性,以硅烷偶联剂KH-570,分散剂BYK-163和钛酸酯偶联剂NDZ-201对纳米二氧化硅进行表面改性.通过沉降率、FTIR和SEM等表征评定方法,对产物结构和性能进行了分析.结果表明,KH570能够对二氧化硅进行改性,并且效果优良.最佳改性条件为:改性剂用量为5%,反应时间30min左右,改性后的纳米二氧化硅用于丙烯酸聚氨酯防腐涂料中,涂料各项性能都有较大改善,均达到国家标准.  相似文献   
65.
在水溶液中用柠檬酸钾还原氯金酸的方法合成了粒径为30~40nm的金纳米粒子,并用透射电镜和紫外可见光谱进行了表征;然后在表面经PVP修饰的导电玻璃上以自组装的方式构筑了金纳米粒子的二维有序阵列,并用扫描电镜和紫外可见光谱进行了表征;以所制备的金纳米粒子二维有序阵列作为电极,对硝基苯酚的电化学响应得到明显提高,金纳米有序阵列电极有望成为检测废水中对硝基苯酚的电化学传感器.  相似文献   
66.
磁性纳米粒子在生物成像方面已经得到了广泛的应用,并且有着良好的发展前景.就纳米多功能磁共振造影剂的种类、合成、表面修饰及其生物应用等方面介绍了近年来国内外在这一领域的最新进展.  相似文献   
67.
A novel carbon composite electrode modified with bismuth oxide nanoparticles and the ionic liquid n-octylpyridinium hexafluorophosphate was fabricated and used to simultaneously determine cadmium and lead levels using square wave anodic stripping voltammetry.This electrode combines the unique advantages of nanomaterials and ionic liquid with the low cost and easy fabrication of the carbon composite electrode.Compared with the traditional binder based composite electrode,our electrode exhibited well-defined and separate stripping voltammetric peaks for cadmium and lead.Furthermore,the antifouling capacity of the bismuth film electrode was significantly improved by the ionic liquid.Under optimized conditions,the linear range of the composite electrode was from 3.0 to 30.0 μg L-1 for both metal ions with a detection limit of 0.15 μg L-1 for cadmium and 0.21 μg L-1 for lead.Trial milk sample analyses showed that the modified electrode was sensitive,reliable and effective for the determination of trace heavy metals,holding great promise for routine analysis applications.  相似文献   
68.
Magnetic nanoparticles (MNPs) have great potential for a wide use in various biomedical applications due to their unusual properties. It is critical for many applications that the biological effects of nanoparticles are studied in depth. To date, many disparate results can be found in the literature regarding nanoparticle-biological factors interactions. This review highlights recent developments in this field with particular focuses on in vitro MNPs-cell interactions. The effect of MNPs properties on cellular uptake and cytotoxicity evaluation of MNPs were discussed. Some employed methods are also included. Moreover, nanoparticle-cell interactions are mediated by the presence of proteins absorbed from biological fluids on the nanoparticle. Many questions remain on the effect of nanoparticle surface (in addition to nanoparticle size) on protein adsorption. We review papers related to this point too.  相似文献   
69.
One of the major challenges for successful gene therapy is improving the transfection efficiency of non-viral vectors. Magnetic nanoparticles (MNPs) have been developed as enhancers of non-viral vehicles. We prepared MNPs and modified them with polyethyleneimine (PEI), citric acid (CA) or carboxylmethyl-dextran (CMD). Both positively charged MNPs (MNPs@PEI) and negatively charged MNPs (MNPs@CA, MNPs@CMD) could spontaneously form transfection complexes (magnetofectins) with plasmid DNA and PEI/liposome via electrostatic self-assembly. Our results showed as-prepared magnetofectins apparently enhanced PEI/liposome transfection efficiency and/or gene expression level into COS-7 cells with reduced transfection time from 4 h to 15 min under a magnetic field in vitro. Meanwhile, the effect of magnetofection was cell line-dependant. These results suggest that charged MNPs could improve transfection efficiency for non-viral vectors by simply mixing with them and by exerting a magnetic force. Thus such MNPs provide a convenient platform for further applications of gene delivery.  相似文献   
70.
Silica nanoparticles have been prepared from tetraethylorthosilicate dissolved in ethanol followed by base-catalyzed condensation.Earlier works reported that at least four parameters,namely concentrati...  相似文献   
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