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81.
82.
A series of Fe(III), Co(II) and Cu(II) complexes of 8‐quinolinol were encapsulated into the supercages of zeolite? Y and characterized by X‐ray diffraction, SEM, N2 adsorption/desorption, FT‐IR, UV–vis spectroscopy, elemental analysis, ICP‐AES and TG/DSC measurements. The encapsulation was achieved by a flexible ligand method in which the transition metal cations were first ion‐exchanged into zeolite Y and then complexed with 8‐quinolinol ligand. The metal‐exchanged zeolites, metal complexes encapsulated in zeolite–Y plus non‐encapsulated homogeneous counterparts were all screened as catalysts for the aerobic oxidation of styrene under mild conditions. It was found that the encapsulated complexes always showed better activity than their respective non‐encapsulated counterparts. Moreover, the encapsulated iron complex showed good recoverability without significant loss of activity and selectivity within successive runs. Heterogeneity test for this catalyst confirmed its high stability against leaching of active complex species into solution. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
83.
面向对象程序设计的核心概念在C++中的实现 总被引:2,自引:0,他引:2
解释了面向对象程序设计的3个核心概念-封装,继承,多态,并通过实例给出了其在C 语言中的实现,这样,可把握重点,以更好地学习C 语言。 相似文献
84.
Triorganotin halides, oxides and sulphides can be dissolved in molten, mixed-metal acetates at ca 140–160°C without decomposition; quenching provides glasses into which are encapsulated the organotin species. Halide/acetate and oxide/acetate, but not sulphide/acetate, exchanges occur in the melt. Only partial exchange was found for hindered trineophyl tin chloride [(PhCMe2CH2)3SnCl], in contrast to the complete exchanges observed for the butyl (Bu), phenyl (Ph) and cyclohexyl (Cy) analogues. Complete oxide/acetate exchange was found for (Bu3Sn)2O, partial exchange occurred for (Cy3Sn)2O, whilst no exchange resulted with bis(trineophyltin) oxide or (Ph3Sn)2O. Tin–tin bonds (e.g. as in Ph3SnSnPh3) and carbon–tin bonds (even the allyl–Sn bond in Bu3SnCH2CH?CH2) are not affected. The acetate glasses dissolve in aqueous media with release of the organotin species and they have potential as slow-release systems which is currently being investigated. 相似文献
85.
Polymersomes Prepared from Thermoresponsive Fluorescent Protein–Polymer Bioconjugates: Capture of and Report on Drug and Protein Payloads
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Chin Ken Wong Alistair J. Laos Dr. Alexander H. Soeriyadi Prof. Jörg Wiedenmann Prof. Paul M. G. Curmi Prof. J. Justin Gooding Dr. Christopher P. Marquis Prof. Martina H. Stenzel Assoc. Prof. Pall Thordarson 《Angewandte Chemie (International ed. in English)》2015,54(18):5317-5322
Polymersomes provide a good platform for targeted drug delivery and the creation of complex (bio)catalytically active systems for research in synthetic biology. To realize these applications requires both spatial control over the encapsulation components in these polymersomes and a means to report where the components are in the polymersomes. To address these twin challenges, we synthesized the protein–polymer bioconjugate PNIPAM‐b‐amilFP497 composed of thermoresponsive poly(N‐isopropylacrylamide) (PNIPAM) and a green‐fluorescent protein variant (amilFP497). Above 37 °C, this bioconjugate forms polymersomes that can (co‐)encapsulate the fluorescent drug doxorubicin and the fluorescent light‐harvesting protein phycoerythrin 545 (PE545). Using fluorescence lifetime imaging microscopy and Förster resonance energy transfer (FLIM‐FRET), we can distinguish the co‐encapsulated PE545 protein inside the polymersome membrane while doxorubicin is found both in the polymersome core and membrane. 相似文献
86.
Individual Surface‐Engineered Microorganisms as Robust Pickering Interfacial Biocatalysts for Resistance‐Minimized Phase‐Transfer Bioconversion
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Zhaowei Chen Haiwei Ji Chuanqi Zhao Enguo Ju Prof. Dr. Jinsong Ren Prof. Dr. Xiaogang Qu 《Angewandte Chemie (International ed. in English)》2015,54(16):4904-4908
A powerful strategy for long‐term and diffusional‐resistance‐minimized whole‐cell biocatalysis in biphasic systems is reported where individually encapsulated bacteria are employed as robust and recyclable Pickering interfacial biocatalysts. By individually immobilizing bacterial cells and optimizing the hydrophobic/hydrophilic balance of the encapsulating magnetic mineral shells, the encased bacteria became interfacially active and locate at the Pickering emulsion interfaces, leading to dramatically enhanced bioconversion performances by minimizing internal and external diffusional resistances. Moreover, in situ product separation and biocatalyst recovery was readily achieved using a remote magnetic field. Importantly, the mineral shell effectively protected the entire cell from long‐term organic‐solvent stress, as shown by the reusability of the biocatalysts for up to 30 cycles, while retaining high stereoselective catalytic activities, cell viabilities, and proliferative abilities. 相似文献
87.
A generalized technique for the encapsulation of nano‐sized NiO particles by styrene‐2‐hydroxyethyl methacrylate copolymer
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M. Shamim Hossan M. Abdur Rahman Klaus Tauer Hideto Minami Hasan Ahmad 《先进技术聚合物》2015,26(9):1047-1052
Encapsulation of nickel oxide (NiO) particles is of great interest to the researchers as such modification produces remarkable improvement in properties and versatility in application potential. In this investigation, nanosized NiO particles were first prepared by calcination of nickel hydroxide precursor obtained using a simple liquid‐phase process. The produced NiO particles were stabilized with oleic acid and then treated with tetraethylorthosilicate to produce NiO/SiO2 composite seed particles. Finally tri‐layered inorganic/organic composite particles were prepared by seeded copolymerization of styrene and 2‐hydroxyethyl methacrylate (HEMA) in the presence of NiO/SiO2 composite seed particles. The produced composite particles named as NiO/SiO2/P(S‐HEMA) were colloidally stable, and the obtained particles were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy and thermogravimetric analyses. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
88.
Controlled Formation of Polymer Nanocapsules with High Diffusion‐Barrier Properties and Prediction of Encapsulation Efficiency
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Ines Hofmeister Prof. Dr. Katharina Landfester Dr. Andreas Taden 《Angewandte Chemie (International ed. in English)》2015,54(1):327-330
Polymer nanocapsules with high diffusion‐barrier performance were designed following simple thermodynamic considerations. Hindered diffusion of the enclosed material leads to high encapsulation efficiencies (EEs), which was demonstrated based on the encapsulation of highly volatile compounds of different chemical natures. Low interactions between core and shell materials are key factors to achieve phase separation and a high diffusion barrier of the resulting polymeric shell. These interactions can be characterized and quantified using the Hansen solubility parameters. A systematic study of our copolymer system revealed a linear relationship between the Hansen parameter for hydrogen bonding (δh) and encapsulation efficiencies which enables the prediction of encapsulated amounts for any material. Furthermore EEs of poorly encapsulated materials can be increased by mixing them with a mediator compound to give lower overall δh values. 相似文献
89.
Encapsulation of Functional Organic Compounds in Nanoglass for Optically Anisotropic Coatings
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Matthias Stöter Dr. Bernhard Biersack Dr. Sabine Rosenfeldt Markus J. Leitl Dr. Hussein Kalo Prof. Dr. Rainer Schobert Prof. Dr. Hartmut Yersin Prof. Geoffrey A. Ozin Prof. Dr. Stephan Förster Prof. Dr. Josef Breu 《Angewandte Chemie (International ed. in English)》2015,54(16):4963-4967
A novel approach is presented for the encapsulation of organic functional molecules between two sheets of 1 nm thin silicate layers, which like glass are transparent and chemically stable. An ordered heterostructure with organic interlayers strictly alternating with osmotically swelling sodium interlayers can be spontaneously delaminated into double stacks with the organic interlayers sandwiched between two silicate layers. The double stacks show high aspect ratios of >1000 (typical lateral extension 5000 nm, thickness 4.5 nm). This newly developed technique can be used to mask hydrophobic functional molecules and render them completely dispersible in water. The combination of the structural anisotropy of the silicate layers and a preferred orientation of molecules confined in the interlayer space allows polymer nanocomposite films to be cast with a well‐defined orientation of the encapsulated molecules, thus rendering the optical properties of the nanocoatings anisotropic. 相似文献
90.
New Polyurethane/Docosane Microcapsules as Phase‐Change Materials for Thermal Energy Storage
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Dr. Paula Felix De Castro Prof. Dmitry G. Shchukin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(31):11174-11179
Polyurethane microcapsules were prepared by mini‐emulsion interfacial polymerization for encapsulation of phase‐change material (n‐docosane) for energy storage. Three steps were followed with the aim to optimize synthesis conditions of the microcapsules. First, polyurethane microcapsules based on silicone oil core as an inert template with different silicone oil/poly(ethylene glycol)/4,4′‐diphenylmethane diisocyanate wt % ratio were synthesized. The surface morphology of the capsules was analyzed by scanning electronic microscopy (SEM) and the chemical nature of the shell was monitored by Fourier transform infrared spectroscopy (FT‐IR). Capsules with the silicone oil/poly(ethylene glycol)/4,4′‐diphenylmethane diisocyanate 10/20/20 wt % ratio showed the best morphological features and shell stability with average particle size about 4 μm, and were selected for the microencapsulation of the n‐docosane. In the second stage, half of the composition of silicone oil was replaced with n‐docosane and, finally, the whole silicone oil content was replaced with docosane following the same synthetic procedure used for silicone oil containing capsules. Thermal and cycling stability of the capsules were investigated by thermal gravimetric analysis (TGA) and the phase‐change behavior was evaluated by differential scanning calorimetry (DSC). 相似文献