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1.
壳聚糖基载药纳米微粒制备研究进展   总被引:14,自引:3,他引:14  
有关可生物降解多糖类纳米微粒用作给药载体的研究,近年颇受重视。简要评述了壳聚糖基载药纳米微粒的制备方法,包括共价交联、离子诱导、沉淀析出、大分子复合和自组装方法及其研究进展。  相似文献   

2.
CdS半导体纳米微粒的复合与组装   总被引:9,自引:0,他引:9  
总结了CdS半导体纳米微粒的复合与组装,并介绍了其应用方面的研究。  相似文献   

3.
在纳米粒子的应用中,确定溶液中纳米微粒的含量十分重要。目前,对于含有纳米微粒的水溶液体系中纳米微粒的分析,如纳米复合镀溶液、纳米复合化学镀溶液、纳米浆料等基本采用重量分析法。重量分析法存在操作工序多、费时、无法实现适时监控等缺点,而且由于纳米微粒悬浮性很强,在多次清洗、分离过程中难免丢样,实验误差较大。  相似文献   

4.
用新的方法将PbS纳米微粒复合在聚苯乙烯光学塑料中,并利用吸收光谱、小角X-光散射和透射电镜等方法研究了不同反应条件对复合的硫化铅(PbS)纳米微粒粒度及分布的影响.结果表明,在一定范围内H2S的量和初始含铅聚合物浓度对纳米微粒的粒度影响很小,但对其粒度分布影响较大;当H2S与Pb2+的摩尔比及初始含铅聚合物浓度均较大时,纳米微粒的粒度分布变宽.实验结果表明复合于聚苯乙烯中的PbS的粒度分布是由溶液中反应决定的,本体聚合反应时对PbS微粒的粒度分布影响很小.因此控制适当反应条件,可以得到粒度分布均一、分散均匀且透明性好的PbS纳米微粒复合有机光学材料.  相似文献   

5.
仿贝壳自组装纳米复合薄膜的制备及结构表征   总被引:6,自引:0,他引:6  
利用超分子自组装方法在普通玻璃表面制备了仿贝壳有机 无机复合纳米薄膜.采用X射线衍射仪、傅立叶红外光谱仪、紫外 可见吸收光谱仪、透射电子显微镜对薄膜结构进行了表征.结果表明这种薄膜具有有机 无机有序交替的层状纳米复合结构,聚合前层间距为4.20 nm,聚合后层间距为3.91 nm.无机层由TiO2纳米微粒构成.  相似文献   

6.
银纳米粒子的一步合成与表征   总被引:1,自引:1,他引:0  
在水和乙醇溶液中,以对巯基苯胺作为还原剂,利用一步法合成了银纳米微粒,并利用拉曼光谱仪考察了对巯基苯胺在银纳米微粒表面的自组装行为.结果表明,合成的银纳米微粒的形貌与介质的pH值密切相关;对巯基苯胺可在银纳米微粒表面自组装.  相似文献   

7.
硫化镉钠米微粒在聚合物网络中的组装   总被引:14,自引:0,他引:14  
硫化镉钠米微粒在聚合物网络中的组装黄金满,杨毅,杨柏,刘式墉,沈家骢(吉林大学分子光谱与分子结构重点实验室、集成光电子国家重点实验室,长春,130023)关键词组装,纳米微粒,离子交换,透射电子显微镜,电子衍射由于纳米半导体微粒的物理和化学性质介于分...  相似文献   

8.
聚合物对硫化铅钠米微粒的稳定作用   总被引:6,自引:1,他引:6  
以含铅聚合物微凝胶与H2S气体反应制得PbS纳米微粒/聚合物复合体系,利用小角X光散射方法对复合在聚合物中的PbS纳米微粒的粒度及分布进行了表征,研究了不同反应条件对其粒度及复合体系稳定性的影响。  相似文献   

9.
巩雁军 《化学进展》2007,19(4):502-509
本文简单介绍了半导体荧光纳米微粒(又称量子点)的基本概念和荧光性质,评述了II-VI族半导体荧光纳米微粒(NCs)的制备和性质研究进展,尤其对基于荧光纳米微粒的复合荧光微球的制备、性质及改进方法进行了详细的讨论,指出目前存在问题和发展方向。  相似文献   

10.
纳米结构TiO2/SiO2的逐层自组装   总被引:7,自引:0,他引:7  
采用逐层自组装方法在二氧化硅球表面交替组装了十二烷基硫酸钠单分子膜和 二氧化钛纳米粒子膜,该复合多层膜经高温假烧后得到了核壳型纳米结构二氧化钛 /二氧化硅复合颗粒.利用XRD,SEM,X射线能谱等对复合颗粒进行了表征.结果 表明:二氧化肽在复合颗粒表面排列紧密、均匀,粒径在50nm左右,为锐钛矿型结 构.复合颗粒中二氧化肽的含量随组装层数的增加而均匀增加.  相似文献   

11.
程志林  万惠霖刘赞 《中国化学》2004,22(12):1454-1455
Zeolite A rods by self-assembly of zeolite A microcrystal were successfully synthesized by microwave-assisted hydrotherrnal synthesis. The average size of zeolite crystals consisting of self-assembling materials was about 300 nm and the length of zeolite rods was in the range of 15--30μm.  相似文献   

12.
Photochromic diarylethene derivatives having different lengths and numbers of poly(ethylene glycol) side chains were synthesized and their photochromic property and self‐assembling behavior were investigated. The self‐assembling behavior of the derivatives strongly depends upon the ratio between the hydrophobic core and the amphiphilic side chain. According to UV/Vis absorption spectroscopy, CD spectroscopy, and dynamic light scattering experiments, these derivatives showed different size distribution of the assembled structures and different solubility in water. The intensity of the induced CD signal, which was observed in the closed‐ring isomer, was the largest for the molecule having two hexaethylene glycol side chains. The relationship between the core‐chain ratio and regularity of the self‐assembled structure has been investigated.  相似文献   

13.
Morphological control of nanomaterials is of great interest due to their size and shape-dependent chemical and physical properties and very important applications in many fields such as biomedicine, sensors, electronics and others. In this paper, we reported a simple strategy for synthesizing gold nanowire assembling architecture at room temperature. It is found that two important factors, the proper volume ratio of ethanol to water and poly(vinyl pyrrolidone) (PVP), will play important roles in synthesizing flower-like short gold nanowire assembling spheres. Furthermore, the obtained flower-like gold assembling spheres with high surface-to-volume ratio have been employed as enhancing materials for electrochemical sensing H2O2. The present electrochemical sensing platform exhibited good electrocatalytic activity towards the reduction of H2O2. The detection limit for H2O2 was found to be 1.2 μM, which was lower than certain enzyme-based biosensors.  相似文献   

14.
The flow field-flow fractionation (FIFFF) technique is a promising method for separating and analysing particles and large size macromolecules from a few nanometers to approximately 50 μm. A new fractionation channel is described featuring well defined flow conditions even for low channel heights with convenient assembling and operations features. The application of the new flow field-flow fractionation channel is proved by the analysis of pigments and other small particles of technical interest in the submicrometer range. The experimental results including multimodal size distributions are presented and discussed.  相似文献   

15.
The electron affinity of small boron clusters and boron nanoparticles and fullerenes (B n ) has been calculated as function of their size. The energetic stability of the small clusters is considered, and a mechanism for their assembling into large nanosystems is suggested.  相似文献   

16.
Zahoransky RA  Dummin H  Laile E  Schauer T 《Talanta》1997,44(12):2225-2230
The flow field-flow fractionation (FIFFF) technique is a promising method for separating and analysing particles and large size macromolecules from a few nanometers to approximately 50 μm. A new fractionation channel is described featuring well defined flow conditions even for low channel heights with convenient assembling and operations features. The application of the new flow field-flow fractionation channel is proved by the analysis of pigments and other small particles of technical interest in the submicrometer range. The experimental results including multimodal size distributions are presented and discussed.  相似文献   

17.
The imposing structures of the marine polyether ladder toxins have inspired synthetic chemists to develop many clever methods for assembling these complex skeletons. One intriguing strategy is to use a short and reliable sequence of reactions to build successive rings in an iterative fashion. The ideal approach should tolerate variation in ring size and substitution at the bridgehead positions. This paper offers an overview of recent progress in this field.  相似文献   

18.
Many molecules that could manipulate cellular function are not practical due to their large size and concomitant undesirable pharmocokinetic properties. Here, we describe a bioorthogonal, highly stable boronate ester (HiSBE) synthesis and use this reaction to synthesize a biologically active molecule from smaller precursors in a physiological context. The rapid rate of HiSBE synthesis suggests that it may be useful for assembling a wide variety of biologically active molecules in physiological solutions.  相似文献   

19.
In this study, the stereocomplexation between a novel stereospecific cyclic vinyl polymer, that is, cyclic syndiotactic poly(methyl methacrylate) (st‐PMMA), with the complementary linear isotactic (it‐) PMMA was investigated. Surprising new insight into the effects of the topology (i.e., end groups), size, and tacticity of the assembling components on stereocomplex formation was obtained. Characterization of the stereocomplexes revealed that the self‐assembly of cyclic st‐PMMAs and linear it‐PMMAs resulted in the formation of an unprecedented “polypseudorotaxane‐type” supramolecular assembly. This stereocomplex exhibited remarkably different physical properties as compared to the conventional PMMA triple‐helix stereocomplex as a result of the restricted topology imposed by the cyclic st‐PMMA assembling component.  相似文献   

20.
主要介绍近几年发展的用于生物大分子自组装功能膜的三种逐层(LBL)自组装技术与制备方法,酰胺化反应自组装技术、生物分子的特异识别自组装技术、分子沉积自组装技术;同时总结了自组装功能膜的结构、特性的表征方法,主要有AFM、TEM、循环伏安法、石英晶体微天平(QCM)技术、UV/VIS、XPS方法等。  相似文献   

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