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101.
A Molecular Platform for Multistate Near‐Infrared Electrochromism and Flip‐Flop,Flip‐Flap‐Flop,and Ternary Memory 下载免费PDF全文
Bin‐Bin Cui Jian‐Hong Tang Jiannian Yao Yu‐Wu Zhong 《Angewandte Chemie (International ed. in English)》2015,54(32):9192-9197
A diruthenium complex with a redox‐active amine bridge has been designed, synthesized, and studied by single‐crystal X‐ray analysis and DFT and TDDFT calculations. It shows three well‐separated redox processes with exclusive near‐infrared (NIR) absorbance at each redox state. The electropolymerized film of a related vinyl‐functionalized complex displays multistate NIR electrochromism with low operational potential, good contrast ratio, and long retention time. Flip‐flop, flip‐flap‐flop, and ternary memories have been realized by using the obtained film (ca. 15–20 nm thick) with three electrochemical inputs and three NIR optical outputs that each displays three levels of signal intensity. 相似文献
102.
103.
实验发现,盐酸四环素能够很好吸附到Nafion膜上,动力学研究表明其吸附是与浓度相关并由扩散控制的一级动力学过程,扩散系数为8.5×10-9 cm2 s-1,遵循BET吸附等温线,表明其多层吸附特性.研究表明,当吸附了盐酸四环素的Nafion膜浸入合适浓度的氯金酸溶液时,盐酸四环素能够介导金微纳米晶体在Nafion膜上的生长,且通过简单改变氯金酸溶液的浓度,可以调控金微纳米晶体的形态.这一实验结果为金属微纳米材料Nafion聚合物复合膜的制备提供了新思路,这种金微纳米材料Nafion聚合物复合膜在化学生物传感设计和材料科学领域具有潜在的应用价值. 相似文献
104.
We successfully synthesized the first hemin-montmorillonite bio-conjugate with an amino acid residue to mimic natural peroxidase enzyme. Histamine was intercalated in montmorillonite by cation exchange, then a hemin molecule was loaded onto the histamine-montmorillonite with an adsorption capacity of 7.0 mg g-1. The hemin-histamine-montmorillonite conjugate shows high peroxidase activity as indicated by the oxidation of guaiacol, which is attributed to the activation of hemin by Fe–N complex formation between the imidazole group in histamine and the iron ion in the hemin molecule. Temperature- dependent peroxidase activity for this synthesized biomimetic material indicates that raising the reaction temperature could significantly enhance the activity of the conjugate. The biomimetic catalyst has good reusability; nearly 100% activity can be retained after three cycles. Because montmorillonite clay is widely distributed in the environment, this material offers great potential for in situ and ex situ remediation of many organic contaminants in surface/subsurface soils. 相似文献
105.
Ferrocenylethynyl‐Terminated Azobenzenes: Synthesis,Electrochemical, and Photoisomerization Studies 下载免费PDF全文
Jian‐Feng Yan Da‐Qiang Lin Xin‐Gang Wang Kai‐Qiang Wu Dr. Li‐Li Xie Prof. Dr. Yao‐Feng Yuan 《化学:亚洲杂志》2015,10(3):614-621
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
106.
One Step Preparation of Reduced Graphene Oxide/Pd–Fe3O4@Polypyrrole Composites and Their Application in Catalysis 下载免费PDF全文
Dr. Tongjie Yao Hao Wang Quan Zuo Dr. Jie Wu Dr. Xiao Zhang Dr. Fang Cui Dr. Tieyu Cui 《化学:亚洲杂志》2015,10(9):1940-1947
The simple preparation of catalysts with superior catalytic activity and good reusability is highly desirable. Herein, we report a novel strategy to construct reduced graphene oxide (rGO)/Pd–Fe3O4@polypyrrole (PPy) catalysts with Pd and Fe3O4 nanoparticles anchored on a rGO nanosheet surface and wrapped in a PPy shell. The synthesis and assembly of both the Pd and Fe3O4 nanoparticles, the preparation of the PPy layer, and the reduction of graphene oxide nanosheets were finished in one step. In the system, the PPy layer not only prevented aggregation of Pd and Fe3O4 nanoparticles, but also generated a synergistic effect with precursor Pd2+ ions, which led to a high dispersity of as‐prepared Pd nanoparticles. Although the procedure was simplified to one step, the catalytic activity and reusability were not sacrificed. In the reduction of 4‐nitrophenol, their catalytic performance was better than that in recent reports. Moreover, the catalysts showed good reusability owing to their magnetic properties. 相似文献
107.
Qingquan Lu Jian Zhang Pan Peng Guanghui Zhang Zhiliang Huang Hong Yi Jeffrey T. Miller Aiwen Lei 《Chemical science》2015,6(8):4851-4854
An unprecedented single electron redox process in copper catalysis is confirmed using operando X-ray absorption and EPR spectroscopies. The oxidation state of the copper species in the interaction between Cu(ii) and a sulfinic acid at room temperature, and the accurate characterization of the formed Cu(i) are clearly shown using operando X-ray absorption and EPR evidence. Further investigation of anion effects on Cu(ii) discloses that bromine ions can dramatically increase the rate of the redox process. Moreover, it is proven that the sulfinic acids are converted into sulfonyl radicals, which can be trapped by 2-arylacrylic acids and various valuable β-keto sulfones are synthesized with good to excellent yields under mild conditions. 相似文献
108.
Wei Shi Jian‐Jun Liu Xiang‐Ping Ou Chang‐Cang Huang 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(4):289-293
A homochiral helical three‐dimensional coordination polymer, poly[[(μ2‐acetato‐κ3O,O′:O)(hydroxido‐κO)(μ4‐5‐nicotinamido‐1H‐1,2,3,4‐tetrazol‐1‐ido‐κ5N1,O:N2:N4:N5)(μ3‐5‐nicotinamido‐1H‐1,2,3,4‐tetrazol‐1‐ido‐κ4N1,O:N2:N4:N5)dicadmium(II)] 0.75‐hydrate], {[Cd2(C7H5N6O)2(CH3COO)(OH)]·0.75H2O}n, was synthesized by the reaction of cadmium acetate, N‐(1H‐tetrazol‐5‐yl)isonicotinamide (H‐NTIA), ethanol and H2O under hydrothermal conditions. The asymmetric unit contains two crystallographically independent CdII cations, two deprotonated 5‐nicotinamido‐1H‐1,2,3,4‐tetrazol‐1‐ide (NTIA−) ligands, one acetate anion, one hydroxide anion and three independent partially occupied water sites. The two CdII cations, with six‐coordinated octahedral and seven‐coordinated pentagonal bipyramidal geometries are located on general sites. The tetrazole group of one symmetry‐independent NTIA− ligand links one of the independent CdII cations into 61 helical chains, while the other NTIA− ligand links the other independent CdII cations into similar but unequal 61 helical chains. These chains, with a pitch of 24.937 (5) Å, intertwine into a double‐stranded helix. Each of the double‐stranded 61 helices is further connected to six adjacent helical chains through an acetate μ2‐O atom and the tetrazole group of the NTIA− ligand into a three‐dimensional framework. The helical channel is occupied by the isonicotinamide groups of NTIA− ligands and two helices are connected to each other through the pyridine N and carbonyl O atoms of isonicotinamide groups. In addition, N—H...O and O—H...N hydrogen bonds exist in the complex. 相似文献
109.
Nanomaterials with both superhydrophobic surface properties as well as photocatalytic activities could have important industrial applications. Herein, we synthesized CeVO4 nanocrystals with hexagonal nanoplate structures from the reaction of decavanadate (K6V10O28⋅9 H2O) and CeCl3⋅H2O precursors via a hydrothermal method. This synthetic route has four advantages: 1) the reaction condition is relatively mild, 2) it doesn′t need surfactants or templates, 3) it requires no expensive equipment, and 4) products are of higher purity. During synthesis, solution pH, and reaction temperature were found to play important roles in determining the growth process and final morphologies of the CeVO4 products. These products were characterized spectrophotometrically and via scanning and transmission electron microscopy. Furthermore, the wettability of the as-synthesized film CeVO4 nanoplates was studied by measuring water contact angle (CA). The largest CA measured was at 169.5 ° for a glass substrate treated with 0.06 g mL−1 CeVO4 followed by 2 % 1 H, 1 H, 2 H, 2 H-perfluorodecyltriethoxysilane. Finally, the CeVO4 nanoplates exhibited excellent photocatalytic activity in degradation of rhodamine B (RhB) under UV irradiation and was stable even after repeated cycles of use. 相似文献
110.
Da-Wei Zuo Yi-Tian Gao Yu-Jie Feng Long Xue Yu-Hao Sun 《Theoretical and Mathematical Physics》2017,191(2):725-737
We investigate an AB system, which can be used to describe marginally unstable baroclinic wave packets in a geophysical fluid. Using the generalized Darboux transformation, we obtain higher-order rogue wave solutions and analyze rogue wave propagation and interaction. We obtain bright rogue waves with one and two peaks. For the wave packet amplitude and the mean-flow correction resulting from the self-rectification of the nonlinear wave, the positions and values of the wave crests and troughs are expressed in terms of a parameter describing the state of the basic flow, in terms of a parameter responsible for the interaction of the wave packet and the mean flow, and in terms of the group velocity. We show that the interaction of the wave packet and mean flow and also the group velocity affect the propagation and interaction of the amplitude of the wave packet and the self-rectification of the nonlinear wave. 相似文献