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101.
Numerical Algorithms - In this paper, we present a second-order decoupled scheme based on the artificial compression method for the time-dependent Stokes-Darcy equations. This method not only... 相似文献
102.
Jianxin Guan Rong Wei Antonio Prlj Jie Peng Kun-Han Lin Jitian Liu Han Han Prof. Clémence Corminboeuf Prof. Dahui Zhao Prof. Zhihao Yu Prof. Junrong Zheng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(35):15013-15019
The mechanism of aggregation-induced emission, which overcomes the common aggregation-caused quenching problem in organic optoelectronics, is revealed by monitoring the real time structural evolution and dynamics of electronic excited state with frequency and polarization resolved ultrafast UV/IR spectroscopy and theoretical calculations. The formation of Woodward–Hoffmann cyclic intermediates upon ultraviolet excitation is observed in dilute solutions of tetraphenylethylene and its derivatives but not in their respective solid. The ultrafast cyclization provides an efficient nonradiative relaxation pathway through crossing a conical intersection. Without such a reaction mechanism, the electronic excitation is preserved in the molecular solids and the molecule fluoresces efficiently, aided by the very slow intermolecular charge and energy transfers due to the well separated molecular packing arrangement. The mechanisms can be general for tuning the properties of chromophores in different phases for various important applications. 相似文献
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Back Cover: Ultrasound‐Driven Secondary Self‐Assembly of Amphiphilic β‐Cyclodextrin Dimers (Chem. Eur. J. 13/2015) 下载免费PDF全文
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Qing-Qing Rong Yu-Hong Cui Takahiro Shimada Jian-Shan Wang Takayuki Kitamura 《Acta Mechanica Sinica》2014,30(4):533-539
Self-shaping materials such as shape memory polymers have recently drawn considerable attention owing to their high shape-changing ability in response to changes in ambient conditions, and thereby have promising applications in the biomedical, biosensing, soft robotics and aerospace fields. Their design is a crucial issue of both theoretical and technological interest. Motivated by the shape-changing ability of Towel Gourd tendril helices during swelling/deswelling, we present a strategy for realizing self-shaping function through the deformation of micro/nanohelices. To guide the design and fabrication of selfshaping materials, the shape equations of bent configurations, twisted belts, and helices of slender chiral composite are developed using the variation method. Furthermore, it is numerically shown that the shape changes of a chiral composite can be tuned by the deformation of micro/nanohelices and the fabricated fiber directions. This work paves a new way to create self-shaping composites. 相似文献
107.
Sulfur hexafluoride (SF6) gas has a quite high global warming potential and hence it is required that applying any substitute for SF6 gas. Much interest in the use of a mixture of helium and SF6 as arc quenching medium were investigated indicating a high performance of arc interruption. The calculated values of transport coefficients of mixtures of SF6–He mixtures, at high temperatures are presented in this paper: to the knowledge of the authors, related data have not been reported in the literature. The species composition and thermodynamic properties are determined by the method of Gibbs free energy minimization, using standard thermodynamic tables. The transport properties including electron diffusion coefficients, viscosity, thermal conductivity and electrical conductivity, are evaluated by using the Chapman–Enskog method expanded up to the third-order approximation (second-order for viscosity). Particular attention is paid to the collision integral database by the use of the most accurate and recent cross-sections or interaction potentials available in the literature. The calculations, which assume local thermodynamic equilibrium, are performed in the temperature range from 300 to 30,000 K for different pressures between 0.1 and 16 atm. An evaluation of the current interruption performance by adding He into SF6 is discussed from a microscopic point of view. The properties with regard to SF6–He mixtures calculated here are expected to be reliable because of the improved collision integrals employed. 相似文献
108.
Huanlai Xing Rong Qu Graham Kendall Ruibin Bai 《The Journal of the Operational Research Society》2014,65(8):1261-1277
Network coding is an emerging telecommunication technique, where any intermediate node is allowed to recombine incoming data if necessary. This technique helps to increase the throughput, however, very likely at the cost of huge amount of computational overhead, due to the packet recombination performed (ie coding operations). Hence, it is of practical importance to reduce coding operations while retaining the benefits that network coding brings to us. In this paper, we propose a novel evolutionary algorithm (EA) to minimize the amount of coding operations involved. Different from the state-of-the-art EAs which all use binary encodings for the problem, our EA is based on path-oriented encoding. In this new encoding scheme, each chromosome is represented by a union of paths originating from the source and terminating at one of the receivers. Employing path-oriented encoding leads to a search space where all solutions are feasible, which fundamentally facilitates more efficient search of EAs. Based on the new encoding, we develop three basic operators, that is, initialization, crossover and mutation. In addition, we design a local search operator to improve the solution quality and hence the performance of our EA. The simulation results demonstrate that our EA significantly outperforms the state-of-the-art algorithms in terms of global exploration and computational time. 相似文献
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Jason L. Nyrop Arash Soheili Rong Xiang Fanyu Meng Jacob H. Waldman Xiujuan Jia Rubina Giarre Parmar Benjamin W. Thuronyi J. Michael Williams Lisa DiMichele Michel Journet Bonnie J. Howell Bing Mao Ian W. Davies Steven L. Colletti Laura Sepp‐Lorenzino Erin N. Guidry 《Journal of polymer science. Part A, Polymer chemistry》2014,52(8):1119-1129
Synthetic polymers represent a modifiable class of materials that can serve as adjuvants to address challenges in numerous biomedical and medicinal chemistry applications including the delivery of siRNA. Polymer‐based therapeutics offer unique challenges in both synthesis and characterization as compared to small molecule therapeutics. The ability to control the structure of the polymer is critical in creating a therapeutic. Reported herein, are batch and flow polymerization processes to produce amphiphilic terpolymers through a Lewis acid BF3OEt2‐catalyzed polymerization. These processes focus on controlling reaction variables, which affect polymer structure in this rapid, exothermic, nonliving cationic polymerization. In addition to analytical characterization of the polymers, the in vivo activity of the polymer‐siRNA conjugates is also highlighted—demonstrating that the method of synthesis does affect the in vivo activity of the resulting polymer conjugate. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1119–1129 相似文献