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Two supramolecular complexes, [Cd(bimb)2Cl2] (1) and [Cd(bimb)(DMF)Cl2]·DMF (2) [bimb=4,4′-bis(imidazol-1-ylmethyl)biphenyl], were synthesized by reactions of CdCl2·2.5H2O with bimb ligand in ethanol and N,N′-dimethylformamide (DMF), respectively, and their structures were determined by X-ray crystallography. Complex 1 is an infinite 2D grid network bridged by bimb ligands, and the 2D sheets were further linked by C–H ?Cl hydrogen bonds to form a polycatenated 3D framework. Complex 2 has dicadmium(II) di-μ-chloride units which are connected by bimb bridging ligands to form an infinite non-interpenetrating 2D network. The results provide a nice example of the solvent system exerting a great effect on the construction of supramolecular frameworks. 相似文献
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Pd-catalyzed cross-coupling reactions of various arenediazonium salts with ArSi(OR)3 and KArBF3 have been achieved in good to excellent yields under simple aerobic conditions in water at room temperature. The functional group tolerance makes these transformations as attractive alternatives to the traditional cross-coupling approaches. Furthermore, the sequence can also be performed in a one-pot domino process, omitting the isolation of the intermediate arenediazonium salt. 相似文献
777.
Li Zhao Qiangjun Ling Xiong Liu Chaodong Hang Qiuxia Zhao Fangfei Liu Haibin Gu 《应用有机金属化学》2018,32(2)
Owing to their unique broken symmetry, amphiphilic Janus dendrimers and dendons provide fascinating properties for material, biological, pharmaceutical and biomedical applications. The integration of various organometallic moieties into these macromolecules will further offer the opportunity to form complex and intelligent architectures and materials. Here, we report a novel, simple and multifunctional Janus dendron containing redox‐reversible hydrophobic ferrocene (Fc) unit, complexing‐effective 1,2,3‐triazole ligand and biocompatible hydrophilic triethylene glycol termini. Silver and gold nanoparticles were firstly successfully prepared by using the Janus dendron as the reducing agent of Au(III) and Ag(I), and the stabilizer of the corresponding nanoparticles. The redox response of the Fc moiety was then employed to trigger the release of model drug, rhodamine B, encapsulated in supramolecular micelles formed by the self‐assembly of the Janus dendron. Finally, the precise and excellent metal‐complexing ability of the triazole group in this dendron was fully utilized to stabilize a water‐soluble Cu(I) catalyst, forming supramolecular nanoreactors for the catalysis of the copper(I)‐catalyzed azide alkyne cycloaddition click reaction in only water. The multifunctional characteristics of this dendron highlight the potential for organometallic Janus dendrimers and dendrons in the fields of functional materials and nanomedicines. 相似文献
778.
Conductivity as a Sensor for Monitoring Relative Magnesium Corrosion Rates in Real‐time,in Serum‐containing Media under Cell Culture Conditions 下载免费PDF全文
Kolade Ojo Tracy Hopkins Madhura Joshi Pravahan Salunke Guangqi Zhang Keaton Nahan Zhannping Zhang Daoli Zhao Sarah K. Pixley Vesselin Shanov William R. Heineman 《Electroanalysis》2016,28(12):3000-3008
Because controlling the corrosion rate of magnesium metal will be crucial to the success of biomedical implants containing pure magnesium or magnesium alloys, many ways have been sought to improve in vitro tests to analyze corrosion rates, and also to identify new methods of preparing or post‐processing magnesium. In this work, for an in vitro assay, we explored the use of a commercially available conductivity sensor to study magnesium corrosion under cell culture conditions that duplicate many physiologically appropriate parameters. With this sensor, we studied the corrosion of two previously untested magnesium single crystal samples that differed in surface treatments that could alter corrosion rates. The results show that the relative conductivity changes in (mS/cm) over the total time of immersion were proportional to the corrosion rates in (mm/y) and also to the total magnesium released, as detected by inductively coupled plasma mass spectrometry (ICP‐MS). 相似文献
779.
Jiancong Du Suhui Deng Shangguo Hou Lingling Qiao Jianfang Chen Qing Huang Chunhai Fan Ya Cheng Yun Zhao 《中国光学快报(英文版)》2014,12(4):41101-38
DNA tetrahedral nanostructures are considered to be uew nanocarriers because they can be precisely controlled and hold excellent penetration ability to the cellular membrane. Although the DNA tetrahedral nanostructure is extensively studied in biology and medicine, its behavior in the cells with nanoscale resolution is not understood clearly. In this letter, we demonstrate superrcsolution fluorescence imaging of the distribution of DNA tetrahedral nanostructures in the cell with a simulated emission depletion (STED) microscope, which is built based on a conventional eonfocal microscope and can t)rovide a resolution of 70 nm. 相似文献
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