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41.
A Molecular Platform for Multistate Near‐Infrared Electrochromism and Flip‐Flop,Flip‐Flap‐Flop,and Ternary Memory
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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
42.
The ability to supply suitable blood vessel system is a major challenge for artificial thick tissue engineering. Angiogenesis is a key point during the process of microvascular formation. Many bioactive molecules such as extra cellular matrix(ECM) proteins and adhesion peptides derived from the ECM are applied to promote angiogenesis. In this work, two adhesion peptides, YIGSR and REDV, were selected to modify sodium alginate(ALG) to obtain YIGSR- and REDV-alginate conjugates(ALG-YIGSR, and ALG-REDV, respectively). We mixed the two peptide-conjugates together in a series of concentration ratios to prepare bioactive surfaces for in vitro studies and hydrogel scaffolds for in vivo studies. In vitro studies showed that surfaces modified with 1.09 pmol/mm2 peptide had the best affinity to human umbilical vein endothelial cells(HUVECs) than that with high or low concentrations of peptides. In addition, surfaces modified with dual peptides could significantly promote HUVECs proliferation, where ALG-YIGSR:ALG-REDV at a mole ratio of 5:1 exhibited the best enhancement ability. Furthermore, the in vivo angiogenesis results demonstrated that hydrogel scaffolds composed of mixed ALG-YIGSR and ALG-REDV at the 5:1 ratio had angiogenic induction potential by stimulating new blood vessel formation, and showed higher blood vessel density than scaffolds composed of a single peptide. These results demonstrated that a mixed combination of peptide alginate conjugates could be a potential scaffold to stimulate and induce angiogenesis in tissue engineering applications. 相似文献
43.
Tingting Zhang Wanying Lei Ping Liu José A. Rodriguez Jiaguo Yu Yang Qi Gang Liu Minghua Liu 《Chemical science》2015,6(7):4118-4123
Structure–function correlations are a central theme in heterogeneous (photo)catalysis. In this study, the geometric and electronic structure of perovskite ferroelectric KNbO3 nanowires with respective orthorhombic and monoclinic polymorphs have been systematically addressed. By virtue of aberration-corrected scanning transmission electron microscopy, we directly visualize surface photocatalytic active sites, measure local atomic displacements at an accuracy of several picometers, and quantify ferroelectric polarization combined with first-principles calculations. The photoreactivity of the as-prepared KNbO3 nanowires is assessed toward aqueous rhodamine B degradation under UV light. A synergy between the ferroelectric polarization and electronic structure in photoreactivity enhancement is uncovered, which accounts for the prominent reactivity order: orthorhombic > monoclinic. Additionally, by identifying new photocatalytic products, rhodamine B degradation pathways involving N-deethylation and conjugated structure cleavage are proposed. Our findings not only provide new insights into the structure–photoreactivity relationships in perovskite ferroelectric photocatalysts, but also have broad implications in perovskite-based water splitting and photovoltaics, among others. 相似文献
44.
Kondrateva V. Yu. Martynenko E. A. Pimerzin A. A. Verevkin S. P. 《Russian Journal of Applied Chemistry》2022,95(1):126-134
Russian Journal of Applied Chemistry - Pt/Sup catalysts with SiO2, MCM-48, and Al2O3 supports (Sup) were prepared. The catalysts were studied by methods of low-temperature nitrogen adsorption,... 相似文献
45.
Fedorov S. N. Kuzmich A. S. Agafonova I. G. Sabutskii Yu. E. Guzii A. G. Popov R. S. Ogurtsov V. A. Rakitin O. A. Polonik S. G. 《Russian Chemical Bulletin》2022,71(3):489-495
Russian Chemical Bulletin - Nucleophilic substitution of the chlorine atom in 4,5-dichloro-1,2-dithiol-3-one using 1-thio-β-d-glucopyranose and its 2,3,4,6-tetra-O-acetyl derivative in... 相似文献
46.
Gunko Yu. L. Kozyrin V. A. Kozina O. L. Ananieva E. Yu. Mikhalenko M. G. 《Russian Journal of Electrochemistry》2022,58(1):60-73
Russian Journal of Electrochemistry - The reduction of zinc oxide in a limited volume of the alkaline electrolyte is studied. Methods of chronopotentiometry, chronoamperometry, and... 相似文献
47.
Tkachev V. V. Sayapin Yu. A. Gusakov E. A. Tupaeva I. O. Krasnikova T. A. Shilov G. V. Komissarov V. N. Aldoshin S. M. Minkin V. I. 《Russian Journal of General Chemistry》2022,92(2):206-211
Russian Journal of General Chemistry - Acylation of 5,7-di(tert-butyl)-2-{5,8-dimethyl-4-[(3,5-dimethylphenyl)amino]quinolin-2-yl}-3-[(3,5-dimethylphenyl)amino]tropone leads to... 相似文献
48.
Milutka M. S. Burlov A. S. Vlasenko V. G. Koshchienko Yu. V. Korshunova E. V. Uraev A. I. Trigub A. L. Zubenko A. A. Klimenko A. I. Gusev A. N. 《Russian Journal of General Chemistry》2022,92(7):1297-1308
Russian Journal of General Chemistry - Azomethines were synthesized from 2,4,6-trimethylaniline, salicylaldehyde, and its 3(5)-halogen derivatives, as well as their complexes with zinc(II) (ZnL2).... 相似文献
49.
Soldatova A. E. Tsegelskaya A. Yu. Semenova G. K. Bezsudnov I. V. Polinskaya M. S. Abramov I. G. Kuznetsov A. A. 《Russian Chemical Bulletin》2022,71(4):777-786
Russian Chemical Bulletin - The method of one-stage catalytic polycyclocondensation according to the B4 + AB scheme was used to synthesize new tetraarm star-shaped oligoimides (SOIs) with terminal... 相似文献
50.
Kalinin A. A. Sharipova S. M. Islamova L. N. Fazleeva G. M. Busyurova D. N. Sharipova A. V. Fominykh O. D. Balakina M. Yu. 《Russian Chemical Bulletin》2022,71(5):1009-1018
Russian Chemical Bulletin - Two new D—π—A chromophores with the tricyanofuranyl acceptor (A), an amphi-divinyl quinoxaline π-electron conjugated bridge, and the carbazole or... 相似文献