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1.
谢飞  齐美洲  李文江  王凯  于振云  刘斌 《化学进展》2011,23(12):2522-2533
中空球是壳层结构材料的一个重要分支。与实心球相比较,中空球具有更多特殊和优异的物理及化学性质,例如具有较小的密度、较大的比表面积以及较好的稳定性和表面渗透性,其中无机中空球较有机中空球还具有耐高温、抗老化等优点。因此,近些年来无机中空球备受人们的关注,广泛应用于催化、电池、医药等众多领域。本文结合本课题组在无机氧化物中空球领域的研究和前人的工作,总结了近5年来制备无机中空球的研究进展。将无机中空球的壳层材料分为五大类,包括:无机氧化物、硫化物及硒化物、金属单质、复合物和其他无机材料。将制备方法分成四大类:硬模板法、软模板法、牺牲模板法和无模板法,对每一大类又进一步细分,并且指出了各种方法的优缺点。同时归纳了无机中空球几个重要的应用领域,如药物、电池、气体传感器和光催化领域。最后在此基础上简要展望了无机中空球的研究前景。  相似文献   

2.
可聚合纳米无机氧化物杂化材料在紫外光固化涂料中具有较好的分散性能.与涂料中的单体和预聚物进行光聚合形成有机/无机杂化网络结构的聚合物,从而提高涂料固化膜的热稳定性能、硬度和耐磨性能等,在紫外光固化涂料的制备方面有着广阔的应用前景.目前,该类杂化材料主要采用硅烷偶联剂改性、化学接枝改性和溶胶一凝胶方法制备.本文就可聚合纳...  相似文献   

3.
模板法制备无机氧化物中空微球的研究进展   总被引:1,自引:0,他引:1  
总结了模板法在制备无机氧化物中空微球方面的应用,主要从模板的种类和壳层增长机理两方面进行阐述,并对无机氧化物中空微球的应用及发展前景作了简要介绍。  相似文献   

4.
无机聚合物   总被引:2,自引:0,他引:2  
无机聚合物是在无机化学,有机化学和聚合物化学交叉点上发展起来的,与材料科学紧密相关的化学新领域。无机聚合物的合成及其对组成、结构、性能的研究;对具有特殊功能无机聚合物材料的研究开发是当前化学科学和材料科学的重要课题。本文简要地介绍了无机聚合物的主要内容,包括定义、主要类型、重要无机聚合物及其研究过程。  相似文献   

5.
传统无机材料合成遵循经典晶体生长方式,常以粉末颗粒形式存在,极大地限制了无机材料的性能.高分子材料通过单体的可控聚合与交联实现了材料的连续、可塑制备,极大地扩大了材料的应用范围.借鉴高分子化学中的封端策略,我们将无机离子寡聚体作为无机单体,替代了传统的离子前驱体,实现了无机离子化合物的聚合与交联,从而能够"像制造高分子...  相似文献   

6.
烷氧基硅烷溶胶-凝胶反应机理   总被引:2,自引:0,他引:2  
利用烷氧基硅烷作为前驱体之一,进行溶胶-凝胶(sol-gel)反应制备无机氧化物和有机-无机杂化材料,近几十年来一直是一个研究热点。对烷氧基硅烷的sol-gel反应过程,特别是起始的水解和初步缩合过程已有较多的研究。本文综述了烷氧基硅烷的sol-gel反应机理研究的进展,并对未来发展提出了看法。  相似文献   

7.
马昱  郭宝颜  叶炜浩  刘应亮 《化学通报》2022,85(11):1282-1289
碳点(CDs)与无机材料结合可能改善两者的性能甚至出现新性能。本文重点介绍CDs以下三种性能在无机材料中的应用:利用CDs的发光性能,可将CDs与无机材料结合用于照明、防伪等;利用CDs的紫外吸收性能,可将其与无机材料结合用作紫外屏蔽剂;利用CDs的化学性能可调控无机材料的结构或增强无机材料的性能。最后,展望了CDs在无机材料中的多功能应用,以期为无机材料的创新性发展做出贡献。  相似文献   

8.
新型无机闪烁材料研究进展   总被引:2,自引:0,他引:2  
本文在扼要叙述了无机闪烁材料的发展史后,综述了近十年来新型无机闪烁材料研究中所取得的进展。主要包括BaF_2的闪烁机理;几种新型高发光效率无机闪烁晶体;新一代陶瓷闪烁体和新材料探索方法的突破。  相似文献   

9.
纳米润滑材料研究及应用   总被引:7,自引:0,他引:7  
陈莲英  章文贡 《化学通报》2003,66(6):404-409
介绍了纳米无机单质、无机盐、氢氧化物、氧化物、高分子微球和有机无机纳米微球的摩擦学研究及纳米材料的润滑作用机理、应用现状及其发展前景。  相似文献   

10.
无机材料的仿生合成   总被引:34,自引:0,他引:34  
生物矿化重要的特征之一是细胞分泌的有机基质调制无机矿物的成核和生长, 形成具有特殊组装方式和多级结构特点的生物矿化材料(如骨、牙和贝壳)。仿生合成就是将生物矿化的机理引入无机材料合成, 以有机物的组装体为模板, 去控制无机物的形成,制备具有独特显微结构特点的无机材料, 使材料具有优异的物理和化学性能。仿生合成已成为无机材料化学的研究前沿。本文综述了无机材料仿生合成的发展现状。  相似文献   

11.
New triazole-imidazole and tetrazole-imidazole hybrids were obtained using 2,4,5-triaryl-1-(4-aminophenyl) imidazoles by copper-catalyzedazide-alkyne cycloaddition (CuAAC) and Ugi-azidefour-component(UA-4CRs) process. The synthesis of triazole hybrids was performed in the presence of new copper-incorporated white sandstone nanocatalyst, which was fully characterized by different methods. The construction of newly prepared hybrids was confirmed by spectroscopic techniques. Some of these compounds were evaluated for their anti-cancer properties against MCF-7 cancer cell lines. The absorption and emission parameters of the triazole- and tetrazole-substituted imidazoles were also investigated and compared with each other.  相似文献   

12.
Antibiotics such as norfloxacin and ciprofloxacin are used to treat numerous bacterial infections. The present research work involves the molecular prediction, synthesis, characterization and in vitro antimicrobial activities of molecular hybrids of norfloxacin and ciprofloxacin. First set of compounds involve the substitutions of various amines at third position of ciprofloxacin and norfloxacin. On the other hand, second set of molecular hybrids include the substitution of different amines at seventh position along with linker (─COCH2─). These synthesized compounds were identified by TLC technique and well characterized by various spectroscopic techniques such as IR, NMR, and ESI-MS. Molecular prediction of these newly synthesized compounds have been carried out using the SwissADME, ADMETLab software. Their cytotoxicity parameters have also been studied using Osiris software. It was observed that almost all these molecular hybrids suitable for their drug likeness properties. Further, these newly synthesized compounds were subjected to study their antimicrobial activities in vitro. The third substituted as well as most of seventh substituted molecular hybrids have shown 10-folds increase in their antibacterial activity as compared to the standard drug ciprofloxacin. Some of these compounds have also shown their potency when subjected to study their cytotoxicity test against Escherichia coli AB 1157, proficient to prepare damage in DNA.  相似文献   

13.
This article highlights the history, synthetic routes, material properties, and scope of ethylene/vinyl acetate copolymer (EVA)/clay nanocomposites. These nanocomposites of EVAs are achieved with either unmodified or organomodified layered silicates with different methods. The structures of the resulting polymer/inorganic nanocomposites have been characterized with X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy. The addition of a small amount of clay, typically less than 8 wt %, to the polymer matrix unusually promotes the material properties, such as the mechanical, thermal, and swelling properties, and increases the flame retardancy of these hybrids. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 471–480, 2006  相似文献   

14.
Nylon 6 (PA6)/clay hybrids have been prepared using a direct melt intercalation technique by two processes. One is PA6 melt-mixing with modified clay, the other is PA6 melt-mixing with natural (Na+ base) clay using an ammonium salt bearing long alkyl chains as a polymer/clay reactive compatibilizer. Their structure and flammability properties are characterized by X-ray diffraction, transmission electron microscopy and cone calorimeter experiments. The results of the cone calorimeter experiments show that hybrids made by these two processes have a lower heat release rate peak and higher thermal stability than that of original PA6. Meanwhile, X-ray diffraction was used to investigate PA6/clay hybrids with various cooling histories from the melt, including medium-rate cooling (air cooling) and rapid cooling (water-quenched). In contrast to pure PA6 dominated by the α phase, the addition of clay silicate layers by these two methods favors the formation of the γ crystalline phase in PA6/clay hybrids. Flammability and phase-transition studies confirm that silicate layers added by these two methods have a similar nanoeffect and nanodispersion in the PA6 matrix.  相似文献   

15.
A series of new inorganic/organic hybrid nanomaterials were prepared through the reaction of cage octa(γ-aminopropylsilsesquioxane) with n-butyl glycidyl ether. The structures and properties of these hybrid materials were characterized by Fourier transform infrared spectroscopy, 29Si nuclear magnetic resonance (NMR), 1H-NMR, and mass spectrometry spectra. The hybrid materials were used for improving mechanical and thermal properties of epoxy resin E-51. The results showed that appropriate amount of addition of the hybrids could enhance the fracture elongation ratio and impact strength. The tensile strength decreased with the addition of the hybrids. The thermal properties such as glass transition temperature, antioxidant index, decomposition temperature, and Vicat softening temperature were obviously improved. Scanning electron microscope observation displayed a rough structure inside the cured epoxy resin by the addition of the hybrids. Kinetic study indicated that the curing process was continuous with average activation energy of 48.06 kJ/mol which was based on Kissinger and Flynn–Wall–Ozawa models.  相似文献   

16.
Fluoroaramids have been used as an attractive matrix polymer for composites due to their excellent mechanical and surface properties. Properties of these polymers can be improved further by dispersing silica in these matrices at a nano-scale via the sol–gel process. The role of interfacial interaction on the thermal and mechanical properties in such hybrids has been investigated in the present work. Two types of hybrids have been prepared; one using the aramid matrix with pendant alkoxy groups on the chain and other without. Silica network was developed by addition of tetraethoxysilane and its subsequent hydrolysis and condensation in the polymer matrix. Well dispersed inorganic domains of nanometer scale were obtained in case of matrix with pendant alkoxy groups on the chain, which showed larger increase in the α- and β-relaxation temperatures, storage modulus and thermal stability as compared to the matrix without alkoxy groups. The role of interfacial interaction, and its effect on properties on the fluoroaramid-silica hybrid composites has been discussed.  相似文献   

17.
Semiconducting polymers with π-conjugated backbones show promise in fields such as photovoltaics. Practical applications of conjugated polymers require precise control over the polymer's electronic band structure. Several new classes of density functional approximation, including screened hybrids, semilocal Minnesota functionals, and Rung 3.5 functionals, show potential for improved predictions of conjugated polymer band structures. This work compares these methods to standard global hybrid density functionals for bandgaps and band structures of representative conjugated polymers. The new methods exhibit particular promise for modeling three-dimensionally periodic bulk polymers, which can be problematic for global hybrids.  相似文献   

18.
The synthesis and properties of various norbornadiene/quadricyclane (NBD/QC) fullerene hybrids are reported. By cyclopropanation of C60 with malonates carrying the NBD scaffold a small library of NBD–fullerene monoadducts and NBD–fullerene hexakisadducts was established. The substitution pattern of the NBD scaffold, as well as the electron affinity of the fullerene core within these hybrid systems, has a pronounced impact on the properties of the corresponding energy rich QC derivatives. Based on this, the first direct photoisomerization of NBD–fullerene hybrids to their QC derivatives was achieved. Furthermore, it was possible to use the redox-active fullerene core of a QC–fullerene monoadduct to enable the back reaction to form the corresponding NBD–fullerene monoadduct. Combining these two processes enables switching between NBD and QC simply by changing the irradiation wavelength between 310 and 400 nm. Therefore, turning this usually photo/thermal switch into a pure photoswitch. This not only simplifies the investigation of the underlying processes of the NBD–QC interconversion within the system, but also renders such hybrids interesting for applications as molecular switches.  相似文献   

19.
The important role of pyrazine (pz) and its derivatives in fields such as biochemistry and pharmacology, as well as in the study of magnetic properties, is surveyed. Recognition of these properties without extensive investigations into their structural properties is not possible. This review summarizes interactions that exist between these organic compounds by themselves in the solid state, as well as those in coordination polymers with metal ions and in polyoxometalate‐based hybrids. Complexes based on pyrazine ligands can generate metal–organic framework (MOF) structures that bind polyoxometalates (POMs) through covalent and noncovalent interactions. Some biological and magnetic properties involving these compounds are considered and the effect of hydrogen bonding on their supramolecular architectures is highlighted.  相似文献   

20.
Graphene and graphene oxide (GO) have garnered significant attention due to their exceptional properties. GO, enriched with various functional groups such as epoxy, hydroxyl, and carboxylic groups, has exhibited remarkable potential in biomedical applications. The combination of GO with metals has proven to be a promising platform for cellular imaging, with this study focusing on the preparation of diverse hybrids of GO with metal oxides (GO/MO) and their potential as anticancer agents. In this research, GO is functionalized with MOs like TiO2, Fe3O4, and Cu2O using specific chemical methods and investigated for the anticancer activity for the application as cancer therapeutic agent. The resulting GO/MO hybrids exhibits favorable thermal and mechanical properties. Moreover, their cytotoxicity against human lung cancer cells is assessed in vitro, revealing the promising anticancer activity of GO/MO hybrids. Notably, the GO/Cu2O hybrid demonstrates particularly high cytotoxicity in human lung cancer cells.  相似文献   

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