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981.
Scanning Electrochemical Microscopy for Electrochemical Detection of Single‐base Mismatches by Tagging Ferrocenecarboxylic Acid as a Redox Probe to DNA 下载免费PDF全文
Scanning electrochemical microscopy (SECM) was employed for sensitive detection of single base mismatches (SBMs) in a sandwiched dsDNA. Ferrocenecarboxylic acid (Fc), covalently conjugated to the dsDNA, was oxidized to Fc+ via the DNA‐mediated charge transfer from the underlying gold substrate, and reduced back to Fc by SECM tip generated ferrocyanide. The electrocatalytic oxidation of SECM tip‐generated ferrocyanide was sensitive to presence, as well as the type of SBMs. Apparent standard rate constants (k0app) values for different SBMs, both near the electrode surface and far from it, were evaluated by SECM. The method can detect SBMs independent of their position in dsDNA. 相似文献
982.
Inside Cover: Pt3Co Octapods as Superior Catalysts of CO2 Hydrogenation (Angew. Chem. Int. Ed. 33/2016) 下载免费PDF全文
983.
Composite photocatalyst films have been fabricated by depositing BiVO4 upon TiO2 via a sequential ionic layer adsorption reaction (SILAR) method. The photocatalytic materials were investigated by XRD, TEM, UV/Vis diffuse reflectance, inductively coupled plasma optical emission spectrometry (ICP‐OES), XPS, photoluminescence and Mott–Schottky analyses. SILAR processing was found to deposit monoclinic‐scheelite BiVO4 nanoparticles onto the surface, giving successive improvements in the films′ visible light harvesting. Electrochemical and valence band XPS studies revealed that the prepared heterojunctions have a type II band structure, with the BiVO4 conduction band and valence band lying cathodically shifted from those of TiO2. The photocatalytic activity of the films was measured by the decolourisation of the dye rhodamine 6G using λ>400 nm visible light. It was found that five SILAR cycles was optimal, with a pseudo‐first‐order rate constant of 0.004 min?1. As a reference material, the same SILAR modification has been made to an inactive wide‐band‐gap ZrO2 film, where the mismatch of conduction and valence band energies disallows charge separation. The photocatalytic activity of the BiVO4–ZrO2 system was found to be significantly reduced, highlighting the importance of charge separation across the interface. The mechanism of action of the photocatalysts has also been investigated, in particular the effect of self‐sensitisation by the model organic dye and the ability of the dye to inject electrons into the photocatalyst′s conduction band. 相似文献
984.
Competition between Hydrophilic and Argyrophilic Interactions in Surface Enhanced Raman Spectroscopy 下载免费PDF全文
John T. Kelly Annie K. McClellan Lynn V. Joe Ashley M. Wright Lawson T. Lloyd Prof. Gregory S. Tschumper Prof. Nathan I. Hammer 《Chemphyschem》2016,17(18):2782-2786
The competition for binding and charge‐transfer (CT) from the nitrogen containing heterocycle pyrimidine to either silver or to water in surface enhanced Raman spectroscopy (SERS) is discussed. The correlation between the shifting observed for vibrational normal modes and CT is analyzed both experimentally using Raman spectroscopy and theoretically using electronic structure theory. Discrete features in the Raman spectrum correspond to the binding of either water or silver to each of pyrimidine's nitrogen atoms with comparable frequency shifts. Natural bond orbital (NBO) calculations in each chemical environment reveal that the magnitude of charge transfer from pyrimidine to adjacent silver atoms is only about twice that for water alone. These results suggest that the choice of solvent plays a role in determining the vibrational frequencies of nitrogen containing molecules in SERS experiments. 相似文献
985.
Utku Kaya Benjamin Wacker Gert Lube 《Mathematical Methods in the Applied Sciences》2016,39(13):3576-3590
We consider the time‐dependent magnetic induction model as a step towards the resistive magnetohydrodynamics model in incompressible media. Conforming nodal‐based finite element approximations of the induction model with inf‐sup stable finite elements for the magnetic field and the magnetic pseudo‐pressure are investigated. Based on a residual‐based stabilization technique proposed by Badia and Codina, SIAM J. Numer. Anal. 50 (2012), pp. 398–417, we consider a stabilized nodal‐based finite element method for the numerical solution. Error estimates are given for the semi‐discrete model in space. Finally, we present some examples, for example, for the magnetic flux expulsion problem, Shercliff's test case and singular solutions of the Maxwell problem. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
986.
Poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction agarose resins with 5‐aminobenzimidazole as a functional ligand 下载免费PDF全文
Tao Liu Dong‐Qiang Lin Cun‐Xiang Wang Shan‐Jing Yao 《Journal of separation science》2016,39(16):3130-3136
Hydrophobic charge‐induction chromatography is a new technology for antibody purification. To improve antibody adsorption capacity of hydrophobic charge‐induction resins, new poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction resins with 5‐aminobenzimidazole as a functional ligand were prepared. Adsorption isotherms, kinetics, and dynamic binding behaviors of the poly(glycidyl methacrylate)‐grafted resins prepared were investigated using human immunoglobulin G as a model protein, and the effects of ligand density were discussed. At the moderate ligand density of 330 μmol/g, the saturated adsorption capacity and equilibrium constant reached the maximum of 140 mg/g and 25 mL/mg, respectively, which were both much higher than that of non‐grafted resin with same ligand. In addition, effective pore diffusivity and dynamic binding capacity of human immunoglobulin G onto the poly(glycidyl methacrylate)‐grafted resins also reached the maximum at the moderate ligand density of 330 μmol/g. Dynamic binding capacity at 10% breakthrough was as high as 76.3 mg/g when the linear velocity was 300 cm/h. The results indicated that the suitable polymer grafting combined with the control of ligand density would be a powerful tool to improve protein adsorption of resins, and new poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction resins have a promising potential for antibody purification applications. 相似文献
987.
988.
Photoinduced Charge‐Transfer State of 4‐Carbazolyl‐3‐(trifluoromethyl)benzoic Acid: Photophysical Property and Application to Reduction of Carbon−Halogen Bonds as a Sensitizer 下载免费PDF全文
Prof. Dr. Ryosuke Matsubara Toshiyuki Shimada Prof. Dr. Yasuhiro Kobori Tatsushi Yabuta Prof. Dr. Toshiyuki Osakai Prof. Dr. Masahiko Hayashi 《化学:亚洲杂志》2016,11(14):2006-2010
The photoinduced persistent intramolecular charge‐transfer state of 4‐carbazolyl‐3‐(trifluoromethyl)benzoic acid was confirmed. It showed a higher catalytic activity in terms of yield and selectivity in the photochemical reduction of alkyl halides compared to the parent carbazole. Even unactivated primary alkyl bromides could be reduced by this photocatalyst. The high catalytic activity is rationalized by considering the slower backward single‐electron transfer owing to the spatial separation of the donor and acceptor subunits. 相似文献
989.
对电荷耦合器件进行了不同剂量率的γ辐照实验,通过多种参数的测试探讨了剂量率与电荷耦合器件性能退化的关系,并对损伤的物理机理进行分析。辐照和退火结果表明:暗信号和暗信号非均匀性是γ辐照的敏感参数,电荷转移效率和饱和输出电压随剂量累积有缓慢下降的趋势;暗场像素灰度值整体抬升,像元之间的差异显著增加;电荷耦合器件的暗信号增量与剂量率呈负相关性,器件存在潜在的低剂量率损伤增强效应。分析认为,剂量率效应是由界面态和氧化物陷阱电荷竞争导致的。通过电子-空穴对复合模型、质子输运模型和界面态形成对机理进行了解释。 相似文献
990.