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811.
Russian Journal of General Chemistry - The Grubbs–Hoveyda catalysts have a wide range of applications in catalyzed formation of the carbon-carbon double bonds. In this study, several...  相似文献   
812.
Journal of Thermal Analysis and Calorimetry - Microstructured surfaces have been extensively employed to enhance nucleate boiling. However, enhancement mechanisms have not been fully understood. In...  相似文献   
813.
In this paper, a modified Cyclotriveratrylene was synthesized and linked to a branched Polyethylenimine, and this unique polymeric material was subsequently examined as a potential supramolecular carrier for Doxorubicin. Spectroscopic analysis in different solvents had shown that Doxorubicin was coordinated within the hollow-shaped unit of the armed Cyclotriveratrylene, and the nature of the host–guest complex revealed intrinsic Van der Waals interactions and hydrogen bonding between the host and guest. The strongest interaction was detected in water because of the hydrophobic effect shared between the aromatic groups of the Doxorubicin and Cyclotriveratrylene unit. Density functional theory calculations had also confirmed that in the most stable coordination of Doxorubicin with the cross-linked polymer, the aromatic rings of the Doxorubicin were localized toward the Cyclotriveratrylene core, while its aliphatic chains aligned closer with amino groups, thus forming a compact supramolecular assembly that may confer a shielding effect on Doxorubicin. These observations had emphasized the importance of supramolecular considerations when designing a novel drug delivery platform.  相似文献   
814.
Chen  Li  Chen  Yu  Miao  Lili  Gao  Yiming  Di  Junwei 《Journal of Solid State Electrochemistry》2020,24(2):411-420
Journal of Solid State Electrochemistry - In this work, we reported the photocurrent switching effect on BiVO4 semiconductor as well as its application for construction of a new cathodic...  相似文献   
815.
Journal of Solid State Electrochemistry - In the present work, we demonstrate a strategy of combining boron doping and porosity engineering for a highly modulated carbon component and pore...  相似文献   
816.
Chen  Minhong  Kressner  Daniel 《Numerical Algorithms》2020,84(3):1199-1216
Numerical Algorithms - Recursive blocked algorithms have proven to be highly efficient at the numerical solution of the Sylvester matrix equation and its generalizations. In this work, we show that...  相似文献   
817.
Chen  Hao  Xu  Dongping 《Numerical Algorithms》2020,83(4):1349-1372
Numerical Algorithms - This paper is concerned with the construction of efficient preconditioners for systems arising from implicit Runge-Kutta time discretization methods for one-dimensional and...  相似文献   
818.
Chen  Lifeng  Dong  Zhao  Jiang  Jifa  Zhai  Jianliang 《中国科学 数学(英文版)》2020,63(8):1463-1504
The limiting behavior of stochastic evolution processes with small noise intensity ε is investigated in distribution-based approaches.Let μ~ε be a stationary measure for stochastic process X~ε with small ε and X~0 be a semiflow on a Polish space.Assume that {μ~ε:0 ε≤ε_0} is tight.Then all their limits in the weak sense are X~0-invariant and their supports are contained in the Birkhoff center of X~0.Applications are made to various stochastic evolution systems,including stochastic ordinary differential equations,stochastic partial differential equations,and stochastic functional differential equations driven by Brownian motion or Levy processes.  相似文献   
819.
Covalent organic frameworks (COFs) enable precise integration of various organic building blocks into porous skeletons through topology predesign. Here, we report the first example of COFs by integrating electron withdrawing bromine group onto the skeletons for triboelectric nanogenerators (TENG). The resulting framework exhibits high surface area and good crystallinity. Thus, the bromine functionalized COF has more regular aligned π columns and arrays over the skeleton than bare COFs, which in turn significantly enhances charge transport ability. As a result, bromine functionalized COFs showed higher electrical output performance at 5 Hz with a peak value of short circuit current density of 43.6 μA and output voltage of 416 V, which is 2 and 1.3 times higher than those of bare COFs (21.6 μA and 318 V), respectively. These results demonstrated that this strategy for engineering electron withdrawing groups on the skeleton could open a new aspect of COFs for developing TENG devices.  相似文献   
820.
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