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991.
992.
Tian F Cziferszky M Jiao D Wahlström K Geng J Scherman OA 《Langmuir : the ACS journal of surfaces and colloids》2011,27(4):1387-1390
We demonstrate a supramolecular peptide separation approach by the selective immobilization of peptides bearing an N-terminal tryptophan onto a CB[8]-modified gold substrate, followed by electrochemical release. The CB[8]-stabilized heteroternary complexes were characterized by (1)H NMR, ESI-MS, UV/vis, and fluorescence spectroscopy and cyclic voltammetry. Micropatterned CB[8]-modified gold substrates were found to trap only the recognizable N-tryptophan-containing peptides from a peptide mixture that could be visualized as green peptide arrays under fluorescence microscopy. Subsequently, the bound peptides were released from the modified substrates by the controlled single-electron reduction of viologen. The fully reversible trap-and-release process was repeated for 13 cycles, and the cumulative release profile of the dye-peptide conjugate was monitored by fluorescence spectroscopy, indicating that no degradation occurred. 相似文献
993.
Jing?Zhao Zi-Tao?JiangEmail author Jin?Tan Rong?Li 《Journal of Sol-Gel Science and Technology》2011,58(2):436-441
Monolithic titania materials with macro-mesoporosity bimodal texture have been prepared through a template-free sol–gel approach,
based on the reaction of hydrolysis and polycondensation of titanium isopropoxide promoted by the slow released water from
esterification between acetic acid and methanol under a strong acidic condition. With the coarsening of the titania oligomers,
phase separation and sol–gel transition processes take place so as to form a homogeneous gel system that will change into
a monolith after aging, drying and heat treatment. The synthesized titania monolith possesses a specific surface area of 77 m2 g−1 (calcined at 350 °C), an anatase with partly rutile crystallite structure and great mechanical strength. The synthesis method
applied here is simple and easy to implement as no extra chemical modifier such as poly(ethylene oxide) (PEO) and formamide
is needed to control the process. The properties of biomodal porous structure, satisfactory surface area and high mechanical
strength will enable the monolith to be served as a chromatography column to separate phosphorus organo-compounds. 相似文献
994.
Jin‐Peng Geng Prof. Dr. Zhao‐Xi Wang Qiong‐Fang Wu Ming‐Xing Li Prof. Dr. Hong‐Ping Xiao 《无机化学与普通化学杂志》2011,637(2):301-305
A new manganese(II) complex [Mn3(bidc)2(C2O4)(H2O)10]n ( 1 ) (bidc = benzimidazole‐5,6‐dicarboxylate) was synthesized and characterized by X‐ray crystallography. X‐ray diffraction shows that complex 1 has a neutral, one‐dimensional (1D) brick wall chain structure. With the intramolecular and intermolecular hydrogen bonding interactions, the adjacent chains are joined into a 3D suparmolecular architecture. IR spectroscopy and variable temperature magnetic susceptibility measurements were made, which indicated weak antiferromagnetic coupling between the MnII ions in complex 1 . 相似文献
995.
An all-atom molecular simulation and NMR experiments have been carried out to investigate the interactions and conformations
of glutathione (GSH) in aqueous and DMSO solutions. The simulations started, from different initial conformations, are characterized
by intramolecular distance, radius of gyration, root-mean-square deviation, and solvent-accessible surface. Interestingly,
different behaviors are found in the two different solutions. GSH is highly flexible in an aqueous solution with transitions
to the extended, semifolded, and folded states. However, once GSH reaches the folded state in DMSO, it remains there and becomes
difficult to break down. The NMR results show agreement with the MD simulations. The water molecule is small. It is also a
good proton donor and a good proton acceptor. Water molecules can easily break down the “folded” conformation. In DMSO solution,
the stronger hydrogen bonds and the hydrophobic interactions are more important, which can make the GSH in the folded state
stable. Variations in the distribution of conformations and the hydrogen-bonding network may play an important role in its
function under physiological conditions. 相似文献
996.
Dong‐Cai Zhao Geng‐Jie Xiao Ni Ren Zhan‐Ji Ma Sheng‐Hu Wu 《Surface and interface analysis : SIA》2011,43(11):1392-1396
The composites, such as CFRP and GFRP, have been widely applied in spaceflight, for their low specific gravity, low cost, and additional structural stability. However, the high resistivity of the composites severely inhibits their further applications. Therefore, Cr/Al films with low resistivity and high adhesion were deposited on composites by cathodic arc technique. The films were characterized by pull test, Dektak 8 Stylus Profilometer, SEM, XPS, XRD and Z‐82 standard four probes. Results show that the aluminum film of fcc structure is compact and uniform, with resistivity as low as bulk Al. The adhesion between Cr buffer layer and composite substrate was greatly enhanced because of the formation of the chemical bonds, such as Cr? C, Cr? O and Cr? N, at the Cr/composite interface. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
997.
Keying Zhang Na Zhang Li Zhang Jigui Xu Hongyan Wang Cong Wang Tao Geng 《Mikrochimica acta》2011,173(1-2):135-141
A sensitive amperometric sensor for hydrogen peroxide (HP) was constructed that is based on a glassy carbon electrode (GCE) modified with silver nanoparticles on poly(alizarin yellow R). The polymer was electropolymerized onto the surface of the GCE by cyclic voltammetry (CV), and the AgNPs were then electrodeposited onto its surface. The electrode was characterized by scanning electron microscopy and CV, and used for amperometric determination of HP. The electrode exhibits a favorable catalytic activity towards the reduction of HP, with a linear response range from 1.0???M to 450???M and a detection limit of 0.32???M. The sensor also displays high selectivity, excellent reproducibility, and good long-term stability. Figure
Schematic representation of the preparation process of the HP sensor and catalytic activity towards HP 相似文献
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