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金属有机骨架材料(Metal-Organic Frameworks,MOFs)是一种新型有机-无机杂化材料,其在气体的吸附分离、催化、磁学、生物医学等领域表现出诱人的应用前景。但是,在水分子存在的情况下MOFs结构及性能会受到很大的影响,极大的阻碍了其工业化进程。本文系统介绍了水分子对MOFs结构的破坏机理,并从金属和配体两方面总结了在水分子存在的情况下MOFs的稳定性问题;阐述了水分子的吸附机理以及吸附水分子后MOFs性能的变化;并且对水分子影响问题的研究趋势做了展望,以期为今后的研究提供参考。 相似文献
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金属有机骨架材料(Metal-Organic Frameworks, MOFs)是一种新型有机-无机杂化材料,其在气体的吸附分离、催化、磁学、生物医学等领域表现出诱人的应用前景.但是,在水分子存在的情况下MOFs结构及性能会受到很大的影响,极大的阻碍了其工业化进程.本文系统介绍了水分子对MOFs结构的破坏机理,并从金属和配体两方面总结了在水分子存在的情况下MOFs的稳定性问题;阐述了水分子的吸附机理以及吸附水分子后MOFs性能的变化;并且对水分子影响问题的研究趋势做了展望,以期为今后的研究提供参考. 相似文献
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有机/无机杂化材料因其独特、优异的结构和性能已经成为目前材料领域的研究热点,硫醇-烯/炔点击化学是近年发展起来的一类新型点击化学,以其反应条件温和、速率快、产率高、产物容易分离以及高度选择性等优点受到国内外研究者的广泛关注。本文综述了近年来硫醇-烯/炔点击化学制备有机/无机杂化材料的研究进展,重点介绍了利用硫醇-烯/炔点击化学制备硅类、碳类、金属及金属氧化物类有机/无机杂化材料,并归纳了这些有机/无机杂化材料在生物医用、环境保护、光电材料等方面的应用,最后展望了硫醇-烯/炔点击化学制备有机/无机杂化材料未来的发展方向。 相似文献
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Two new cadmium-substituted polyoxovanadates of [Cd(dien)2]2[(dien)CdAs8V13O41(H2O)].4H2O and [Cd(en)2]2[(en)2Cd2As8V12O40] (2), where dien is diethylenetriamine and en is ethylenediamine, have been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectra, EPR spectra, XRD spectra, TG analyses, magnetic properties, and X-ray crystallography. Single-crystal X-ray diffraction analyses reveal that compounds 1 and 2 possess a discrete and 1D structure, respectively. The former contains an inorganic-organic hybrid monocadmium-substituted polyoxovanadate cluster unit that is derived from the well-known {As8V14O42} cluster, whereas the latter is composed of an inorganic-organic hybrid bicadmium-substituted polyoxovanadate cluster unit that is derived from the well-known {As8V12O40} cluster. 相似文献
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A wide range of polyvanadates can be synthesized from aqueous solutions. Vanadium oxide gels V2O5 · nH2O are formed around the point of zero charge (pH 2). They exhibit a ribbon-like structure. Weak interactions between these ribbons lead to the formation of mesophases in which vanadium oxide gels or sols behave as nematic liquid crystals. Organic species can be easily intercalated between these oxide ribbons leading to the formation of hybrid nanocomposites made of alternative layers of organic and inorganic components. Hybrid materials can also be formed at a higher pH in the presence of large organic ions such as [N(CH3)4]+. They exhibit layered structures in which organic cations lie between polyoxovanadate planes. Such layered structures are not obtained in the presence of anions such as Cl– or I–. Cluster shell polyvanadates are then formed. They are made of negatively charged polyvanadate hollow spheres in which the negative anion is encapsulated. In this case the organic cations behave as counter ions for the formation of the hybrid crystalline network. 相似文献
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Mojtaba Amini Zahra Shekari Ali Akbari Hadi Naslhajian Ayda Sheykhi Esmaeil Karimi Sanjeev Gautam Keun Hwa Chae 《应用有机金属化学》2020,34(4):e5494
Using interfacial polymerization (IP) of m-phenylenediamine aqueous solution containing polyoxovanadate nanoclusters (POV) and trimesoyl chloride (TMC) in organic solution, we fabricated a novel polyamide (PA)- polyoxovanadate nanocluster (POV) nanocomposite membranes (PA-POV TFN). The chemical structures and morphologies of the synthesized membranes were characterized by Fourier transform infrared (FTIR) spectroscopy, atomic force microscope (AFM), scanning electron microscopy (SEM) and water contact angle measurements. Experimental results showed that the performances of PA-POV TFN membranes are remarkably dependent on POV incorporation in the membranes, which could be controlled by using different amounts of POV particles. Moreover, the PA-POV TFN membranes illustrated outstanding antibacterial properties against Gram-negative E. coli. On the other hand, the incorporation of various amounts of POV in the membranes improved the membrane separation performances (water flux and salt rejection) as well as the antibacterial activity in FO process as compared to the original thin-film composite (TFC) polyamide membrane. 相似文献
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Dr. Xinchang Pang Congshan Wan Mengye Wang Prof. Zhiqun Lin 《Angewandte Chemie (International ed. in English)》2014,53(22):5524-5538
Janus structures, named after the ancient two‐faced Roman god Janus, comprise two hemistructures (e.g. hemispheres) with different compositions and functionalities. Much research has been carried out over the past few years on Janus structures because of the intriguing properties and promising potential applications of these unusually shaped materials. This Review discusses recent progress made in the synthesis, properties, and applications of strictly biphasic Janus structures possessing symmetrical structures but made of disparate materials. Depending on the chemical compositions, such biphasic structures can be categorized into soft, hard, and hybrid soft/hard Janus structures of different architectures, including spheres, rodlike, disclike, or any other shape. The main synthetic routes to soft, hard, and hybrid soft/hard Janus structures are summarized and their unique properties and applications are introduced. The perspectives for future research and development are also described. 相似文献
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Rapid developments in materials science and biological mechanisms have greatly boosted the research discoveries of new drug delivery systems. In the past few decades, hundreds of nanoparticle‐based drug carriers have been reported almost on a daily basis, in which new materials, structures, and mechanisms are proposed and evaluated. Standing out among the drug carriers, the hybrid nanoparticle systems offer a great opportunity for the optimization and improvement of conventional chemotherapy. By combining several features of functional components, these hybrid nanoparticles have shown excellent promises of improved biosafety, biocompatibility, multifunctionality, biodegradability, and so forth. In this Personal Account, we highlight the recent research advances of some representative hybrid nanoparticles as drug delivery systems and discuss their design strategies and responsive mechanisms for controlled drug delivery. 相似文献
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A large variety of new polyoxovanadates have been synthesized during the past few years by sol–gel chemistry or hydrothermal methods. These wet chemistry methods offer many advantages compared to the usual solid state syntheses. New open structures have been obtained from aqueous precursors. They result from the self-assembling of ionic species in the solution.Vanadium oxide gels and sols, V2O5·nH2O, are formed around the point of zero charge (pH≈2). They have a ribbon-like structure and exhibit a liquid crystal behavior. These mesophases are similar to those currently observed with nematic polymers. Xerogel layers deposited from V2O5·nH2O gels exhibit some preferred orientation and behave as versatile host structures for intercalation giving new hybrid organic–inorganic nanocomposites.Layered structures are formed around pH≈7 in the presence of large organic cations. They are built of mixed valence polyoxovanadate planes made of [VO5] pyramids and [VO4] tetrahedra. Organic cations lie between the oxide layers where they interact with the negative oxygen of the VO double bonds.Anions can behave as templating agents. Hollow cluster shells are formed around anions that remain encapsulated within the negatively charged polyvanadate cage. Large cations only behave as counter ions for the formation of a neutral crystalline network.It appears that the molecular structure of VV precursors depends mainly on pH, but the way they self-assemble may be governed by other ionic species in the solution. 相似文献
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Stephen Sproules 《Angewandte Chemie (International ed. in English)》2019,58(30):10043-10047
A recent Communication in this journal reported the stabilization of low‐valent iron(I) in a fully oxidized polyoxovanadate. With no ligand‐field argument to support such an assignment, a re‐evaluation of the data accompanied by detailed computational analysis reveals the redox chemistry is localized to the polyoxovanadate, and when reduced, instigates a spin transition at iron. 相似文献
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DNA is the genetic information carrier for most known living organisms on Earth,while proteins are the functional component that carry out most biological processes.Many natural machineries are DNA-protein hybrid complexes to cooperatively and efficiently conduct sophisticated biological tasks.It has drawn increasing interest to the research field to construct artificial DNA-protein hybrid structures towards a variety of applications including biological studies,nanofabrication,biomedical research,etc.In this regard,here in this report we reviewed the up-to-date progress on making DNA-protein hybrid structures,with a particular focus on DNA nanotechnology-enabled programmable assembly of DNA-protein hybrid structures. 相似文献
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π-Conjugated polymers(CPs)represent one of the quite important and rapidly growing branches of flexible electrochromic materials.Electrosynthesized hybrid CPs employing dibenzo pentacycles(fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran)as the backbones have received considerable attention owing to their special structures and interesting electrochromic performances.Recent studies show that polymers from these structures exhibit decent contrast ratios,favorable coloration efficiencies,low switching voltages,fast response time,excellent stability,and color persistence.Intrinsically,their electrochromic properties significantly depend on fine-tailoring of precursor monomer structures,and polymerization techniques and conditions.This review devotes to showing a clear picture of the research progress of dibenzo pentacycle-centered CPs via electrochemical polymerization,including fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran-based hybrid electrochromic polymers.Critical influences of the tailored precursor structures on their electropolymerization and resultant polymer performances are highlighted,aiming at providing an insight for the development of novel fused ring-based polymer electrochromic materials. 相似文献
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通过水热方法合成了一种三维无机-有机多金属钒酸盐[Cu(en)_2]V_6O_(14),并测定了其晶体结构.该化合物经过X-射线单晶衍射、元素分析、红外光谱表征和热失重分析,并研究了它的电化学性质. 相似文献