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101.
The manufacture of three‐dimensional patterned electroactive poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) microstructures with tailored architecture, morphology, and wettability is presented. The patterned microstructures are fabricated using a simple, effective, low cost, and reproducible technique based on microfluidic technology. These novel structures can represent innovative platforms for advanced strategies in a wide range of biotechnological applications, including tissue engineering, drug delivery, microfluidic, and sensors and actuators devices. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1802–1810  相似文献   
102.
A wide range of N‐arylated indoles were selectively synthesized through intermolecular C(aryl)? N bond formation from the corresponding aryl iodides and indoles through Ullmann‐type coupling reactions in the presence of a catalytic amount of Pd immobilized on amidoxime‐functionalized mesoporous SBA‐15 (SBA‐15/AO/Pd(0)) under mild reaction conditions. These cross‐coupled products were obtained in excellent yields under mild conditions at extremely low palladium loading (ca 0.3 mol%), and the heterogeneous catalyst can be readily recovered by simple filtration and reused seven times with loss in its activity. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
103.
A simple, specific and sensitive LC‐MS/MS method was developed and validated for the determination of mesalazine in beagle dog plasma. The plasma samples were prepared by protein precipitation, then the separation of the analyte was achieved on a Waters Spherisorb C6 column (150 × 4.6 mm, 5 µm) with a mobile phase consisting of 0.2% formic acid in water–methanol (20:80, v/v). The flow rate was set at 1.0 mL/min with a split ratio of 3:2. Mass spectrometric detection was achieved by a triple‐quadrupole mass spectrometer equipped with an electrospray source interface in positive ionization mode. Quantitation was performed using selected reaction monitoring of precursor–product ion transitions at m/z 154 → m/z 108 for mesalazine and m/z 285 → m/z 193 for diazepam (internal standard). The linear calibration curve of mesalazine was obtained over the concentration range 50–30,000 ng/mL. The matrix effect of mesalazine was within ±9.8%. The intra‐ and inter‐day precisions were <7.9% and the accuracy (relative error) was within ±3.5%. The validated method was successfully applied to investigate the pharmacokinetics of mesalazine in healthy beagle dogs after rectal administration of mesalazine suppository. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
104.
The development of high‐surface‐area carbon electrodes with a defined pore size distribution and the incorporation of pseudo‐active materials to optimize the overall capacitance and conductivity without destroying the stability are at present important research areas. Composite electrodes of carbon nano‐onions (CNOs) and polypyrrole (Ppy) were fabricated to improve the specific capacitance of a supercapacitor. The carbon nanostructures were uniformly coated with Ppy by chemical polymerization or by electrochemical potentiostatic deposition to form homogenous composites or bilayers. The materials were characterized by transmission‐ and scanning electron microscopy, differential thermogravimetric analyses, FTIR spectroscopy, piezoelectric microgravimetry, and cyclic voltammetry. The composites show higher mechanical and electrochemical stabilities, with high specific capacitances of up to about 800 F g?1 for the CNOs/SDS/Ppy composites (chemical synthesis) and about 1300 F g?1 for the CNOs/Ppy bilayer (electrochemical deposition).  相似文献   
105.
A two‐step synthesis of structurally diverse pyrrole‐containing bicyclic systems is reported. ortho‐Nitro‐haloarenes coupled with vinylic N‐methyliminodiacetic acid (MIDA) boronates generate ortho‐vinyl‐nitroarenes, which undergo a “metal‐free” nitrene insertion, resulting in a new pyrrole ring. This novel synthetic approach has a wide substrate tolerance and it is applicable in the preparation of more complex “drug‐like” molecules. Interestingly, an ortho‐nitro‐allylarene derivative furnished a cyclic β‐aminophosphonate motif.  相似文献   
106.
107.
The synthesis of a metal–organic framework (UiO‐67) functionalised simultaneously with two different transition metal complexes (Ir and Pd or Rh) through a one‐pot procedure is reported for the first time. This has been achieved by an iterative modification of the synthesis parameters combined with characterisation of the resulting materials using different techniques, including X‐ray absorption spectroscopy (XAS). The method also allows the first synthesis of UiO‐67 with a very wide range of loadings (from 4 to 43 mol %) of an iridium complex ([IrCp*(bpydc)(Cl)Cl]2?; bpydc=2,2′‐bipyridine‐5,5′‐dicarboxylate, Cp*=pentamethylcyclopentadienyl) through a pre‐functionalisation methodology.  相似文献   
108.
An organocatalytic asymmetric chlorinative dearomatization of naphthols was realized for the first time, providing chiral naphthalenones with a Cl-containing all-substituted stereocenter in excellent yields and enantioselectivity (up to 97% yield and 96% ee). The reaction features mild reaction conditions, good tolerance of diverse functional groups and simple reaction operation.  相似文献   
109.
A (di)graph is supereulerian if it contains a spanning eulerian sub(di)graph. This property is a relaxation of hamiltonicity. Inspired by this analogy with hamiltonian cycles and by similar results in supereulerian graph theory, we analyze a number of sufficient Ore type conditions for a digraph to be supereulerian. Furthermore, we study the following conjecture due to Thomassé and the first author: if the arc‐connectivity of a digraph is not smaller than its independence number, then the digraph is supereulerian. As a support for this conjecture we prove it for digraphs that are semicomplete multipartite or quasitransitive and verify the analogous statement for undirected graphs.  相似文献   
110.
Four polycyclic norditerpenoids, cephalotanins A–D ( 1 – 4 ) representing three unprecedented carbon skeletons with highly rigid ring systems, were isolated from Cephalotaxus sinensis and structurally characterized by a combination of various methods. Compounds 1 and 2 are new skeletal norditerpenoid trilactones, while 3 and 4 are two norditerpenoids featuring different new carbon skeletons. Biosynthetic pathways for 1 – 4 were proposed by involving diverse and very fascinating chemical events with the coexisting cephalotane troponoids as the precursors. Compound 1 exhibited good NF‐κB inhibition with an IC50 value of 4.12±0.61 μΜ.  相似文献   
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