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91.
A “turn‐on” pattern Fe3+‐selective fluorescent sensor was synthesized and characterized that showed high fluorescence discrimination of Fe3+ over Fe2+ and other tested ions. With a 62‐fold fluorescence enhancement towards Fe3+, the probe was employed to detect Fe3+ in vivo in HeLa cells and Caenorhabditis elegans, and it was also successfully used to elucidate Fe3+ enrichment and exchange infected by innexin3 (Inx3) in hemichannel‐closed Sf9 cells.  相似文献   
92.
Fluoropolymer microtubes with a smooth surface were fabricated in more than 70 % yield via reversible addition fragmentation chain transfer (RAFT) co‐polymerization of N,N′‐methylene bisacrylamide (MBA) gel fibers as both template and monomer, 2‐(perfluoro‐3‐methylbutyl)ethyl acrylate (R‐3420) as co‐monomer, and pentaerythritol tetraacrylate (PET4A) as cross‐linker. The resulting fluoropolymer microtubes were characterized fully by SEM, TEM, EDS, XPS, and FT‐IR. The influence of the monomer composition on the yields and morphologies of the tubes were investigated in detail. The results indicated that polymer microtubes with a smooth surface were obtained at suitable amounts of R‐3420 and PET4A. Because of the decreased solubility of MBA gel fibers, the wall thickness increased as more R‐3420 was used. In the presence of PET4A, the solution polymerization could be facilitated and more R‐3420 could be attached onto the tubes based on FT‐IR analysis. The water contact angle and swelling ratio measurements both revealed the low hydrophilicity and high lipophilicity of the fluoropolymer microtubes, which made the sample able to absorb toluene selectively in a water/toluene two‐phase system.  相似文献   
93.
In this study, two structural isomers α‐PBT and β‐PBT, which only differ in the phenyl substituent position on the quinoline chromophore, have been designed and successfully synthesized. The influences of substituent position on the film morphology and the storage performance of the devices were investigated. Both molecules employed in the memory devices exhibited same nonvolatile binary (write‐once‐read‐many‐times; WORM) characteristics, but the switch threshold voltage (Vth) of the β‐PBT‐based device was clearly lower than that of the α‐PBT‐based device. Simulation results demonstrate that the variation of the phenyl substituent position led to different intermolecular stacking styles and thus to varied grain sizes for each film morphology. This work illustrates that altering the phenyl substituent position on the molecular backbone could improve the quality of the film morphology and reduce power consumption, which is good for the rational design of future advanced organic memory devices (OMDs).  相似文献   
94.
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96.
Ferrocenylethynyl‐terminated derivatives 8 – 12 have been synthesized and characterized by electrochemistry and UV/Vis spectroscopy. The electrochemical and photophysical studies indicate that the electronic communication in ferrocenylethynyl‐substituted derivatives is strongly influenced by the substituted position of the ferrocenylethynyl moiety. In situ electrochemical oxidation or chemical oxidation caused a characteristically weak ligand‐to‐metal charge‐transfer (LMCT) band to appear at 700–1000 nm. Subsequent electrochemical reduction or chemical reduction recovered the most of the original curve and the color of the solution as well. Among the derivatives, compound 8 exhibits the highest cis/trans molar ratio (64:36) in the photostationary state (PSS) upon light irradiation at 365 nm. Compound 8 exhibits excellent fatigue resistance and reversibility under several repeated reversible isomerization cycles.  相似文献   
97.
Recent studies have further demonstrated that the conjugation of noble metal helical nanostructures could alter their optical and catalytic activities. However, the intrinsic isotropic crystal growth of Pt makes the synthesis of high-quality Pt NCs with unique porous or branched nanostructures difficult. In this work, a new, powerful capping agent, N,N-dimethyloctadecylammonium bromide acetate sodium, was synthesized and used to coordinate Pt ions, slowing down the reaction rate. As a result, in aqueous solution, Pt nanohelices with highly ordered horizontal pore channels were successfully fabricated. Importantly, the Pt nanohelices were composed of several sub-2 nm Pt nanowires coiled together around a central point. The as-obtained samples exhibited enhanced photothermal properties compared with the classic Pt nanoparticles.  相似文献   
98.
A series of AuPd@C nanoalloy catalysts with tunable compositions were successfully prepared by a co-reduction method. The use of borane-tert-butylamine complex as reductant and oleylamine as both solvent and reductant was very effective for the preparation of the monodispersed nanoalloy. We evaluated the catalytic activity of these AuPd@C nanoalloys for oxidative dehydrogenative coupling of aniline, which showed better catalytic activity than equal amounts of sole Au@C or Pd@C catalyst. The Au1Pd3@C catalyst exhibited the best performance, indicating that the conversion and selectivity were improved along with the increase of Pd composition. However if the Pd composition was too high in the AuPd alloy, Au1Pd7@C achieved only 81% conversion in this reaction.  相似文献   
99.
Preface     
<正>Organic photovoltaics(OPVs),especially the solutionprocessable organic photovoltaic materials and devices,have attracted great attention in recent years because of the advantages of simple device structure,low cost,light weight and flexibility of the organic solar cells(OSCs).The highest power conversion efficiency of the OSCs has been im-  相似文献   
100.
Conjugated microporous polymers (CMPs) have recently received extensive attention in oil/organic solvent-water separation field as a kind of ideal porous absorbents with tunable porosity, large surface areas, and super-hydrophobicity. However, reports on the application of CMPs in adsorption of hydrophilic contaminants from water are very few. In this work, we studied the adsorption of metronidazole (MNZ), a polar antibiotic, by two kinds of CMPs. The adsorption characteristics of MNZ by the CMPs, including adsorption kinetics, mechanism, and isotherm parameters were calculated. The adsorption kinetics of MNZ was well expressed by the pseudo-second-order model, and the adsorption process was found to be mainly controlled by film diffusion. The adsorption isotherm data agreed well with the Langmuir isotherm model, and the values of free energy E indicated that the adsorption nature of MNZ on the CMPs was physisorption. Increasing dispersion degree of the CMPs in MNZ solution resulted in greater adsorption. This work may provide fundamental guidance for the removal of antibiotics by CMPs.  相似文献   
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