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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
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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
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纳米润滑材料研究及应用 总被引:7,自引:0,他引:7
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
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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
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Gurmeet Kaur Manpreet Kaur Lakhvir Sharad Manisha Bansal 《Journal of heterocyclic chemistry》2020,57(1):225-237
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
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S. K. Srivastava M. Pramanik H. Acharya 《Journal of Polymer Science.Polymer Physics》2006,44(3):471-480
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
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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
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Caihua Ni Guifeng Ni Shengwen Zhang Xiaoya Liu Mingqing Chen Lihua Liu 《Colloid and polymer science》2010,288(4):469-477
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
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Sulaiman Abbas Zahoor Ahmad Fakhreia Al-Sagheer 《Journal of Sol-Gel Science and Technology》2009,52(2):210-218
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
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Janesko BG 《The Journal of chemical physics》2011,134(18):184105
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
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Patrick Lorenz Prof. Dr. Andreas Hirsch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(23):5220-5230
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
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Fatemeh Taghipour Masoud Mirzaei 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(3):231-247
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
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Shweta D. Dabhi Swati Gahlot Sheefa Mirza Medha Pandya Rakesh Rawal Vaibhav Kulshrestha Prafulla K. Jha 《Macromolecular Symposia》2024,413(1):2300086
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