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81.
82.
We study the budding dynamics of individual domains in flat, multicomponent membranes using dissipative particle dynamics (DPD) simulations with varied bead number N, in which addition and deletion of beads based on their density at the membrane boundary is introduced. The budding process of a tubular bud, accompanied by a dynamical transition reflected in the energy and morphology evolutions, is investigated. The simulations show that budding duration is shortened with increasing line tension and depends on the domain size quadratically. At low line tension, increasing bending modulus accelerates budding at first, but suppresses the process as it increases further. In addition, the controlling role of the surface tension in the budding process is also explored. Finally, we use the N-varied DPD to simulate the experimentally observed multicomponent tubular vesicles, and the three bud growth modes are confirmed. 相似文献
83.
Ren T Sun B Chen Z Qu L Yuan H Gao X Wang S He R Zhao F Zhao Y Liu Z Jing X 《The journal of physical chemistry. B》2007,111(23):6344-6348
The photochemical and photophysical properties of the three C121 isomers (I, II, III) were investigated with MADLI-TOF-MS, UV-vis spectra, fluorescence spectra, absorption spectra of their DMA complexes, and theoretical calculations. The three isomers of C121 (I, II, III) have different stabilities under laser irradiation, but isomer I and isomer II show good stability against the heat-induced conversion between different isomers: No conversion between the isomers was found after heating the mixture of isomer I and isomer II at 353 K for 12 h in Ar atmosphere. The results of UV-vis absorption and fluorescence spectra indicate that interactions between two C60 moieties of C60=C=C60 in the ground and singlet states are not significant, C121 (I, II, III) behaves as an electron-acceptor similar to C60. These indicate that the formation of the fullerene chain structure (e.g., C60=C=C60) does not disturb the photochemical and photophysical properties of the C60 monomer itself, even that the properties were enhanced by the formation of the polymer. This is significant for the C60 polymer in photochemical or photoelectronic applications in which C60=C=C60 can be an excellent basic unit of polymers. 相似文献
84.
He X Li Q Li Y Wang N Song Y Liu X Yuan M Xu W Liu H Wang S Shuai Z Zhu D 《The journal of physical chemistry. B》2007,111(28):8063-8068
A chiral tripod-terpyridine ligand is known to coordinate with Ag+. These complexes self-assemble into chiral aggregates at room temperature. Molecular dynamic simulation reveals the cooperation of tripodal ligand structures with Ag(I) cations, which leads to the formation of helical aggregations, thus the chirality. 相似文献
85.
86.
87.
Chi Wu Aizhen Niu Yue Zhao Chengming Li Yuliang Yang 《Macromolecular rapid communications》2001,22(9):704-707
The thermal decomposition of polystyrene clusters prepared by using 4‐methacryloyloxy‐2,2,6,6‐tetramethylpiperidine‐N‐oxyl as a branching agent was studied. The weight‐average molar mass (M̄w) and the radius of gyration (Rg) of the resultant clusters can be scaled as M̄w ∝︁ Rg3.0 ± 0.1, revealing that these clusters have a uniform chain density. Moreover, the dynamic properties of such clusters converge unexpectedly faster than the static properties as the molar mass decreases. 相似文献
88.
Four rate enhancing cases of nitroxide‐mediated living free‐radical polymerizations are simulated by the Monte Carlo method to investigate the effects of parameters on kinetics and molecular weight distribution of the resulting polymers. In all cases the equilibrium between growing and dormant chains shifts in favor of the growing chains under corresponding reaction conditions. The polymerization rates are therefore increased substantially without much loss in control of molecular weight and distribution of the products. The optimization of rate‐enhancement in living free‐radical polymerization is also discussed. 相似文献
89.
Yuliang Yang 《Macromolecular theory and simulations》1998,7(5):521-549
The spring-and-bead model proposed by Rouse and Zimm can theoretically treat the viscoelastic behaviour of polymers. In this paper, we first point out that the Rouse and Zimm matrices in the molecular theory of polymer viscoelasticities are equivalent to the adjacency matrix and admittance (or Kirchhoff) matrix in graph theory, respectively. In order to solve the eigen-value problems of Rouse and Zimm matrices, the matrices are first represented by their corresponding eigen-graphs, which reflect the topological structure of the real chain. Starting from the eigen-graph, instead of tedious mathematics, the eigen-value problems are solved by a series of simple graphic operations, such as cutting-off the bonds, removing the closed pathways, etc. The eigen-polynomial of Rouse and Zimm matrices and the viscoelastic properties of the chain are obtained by using the theorems given in this paper. It is also shown that the eigen-polynomial of the chain can be greatly reduced if the chain graph has elements of symmetry. As the Rouse theory of viscoelasticity is closely related to the conformational statistics of Gaussian chains, it is demonstrated that the graph-theoretic approach developed here can also be applied to solve the configurational properties of Gaussian chains, such as the distribution function of the radius of gyration and its moments, the shape of a Gaussian chain, etc. We have also demonstrated that the graph-theoretic approach developed here is also applicable to copolymeric chains. 相似文献
90.
Hui Chen Kean Chen Laibing Luo Dr. Xingwei Liu Zhi Wang Dr. Along Zhao Dr. Hui Li Prof. Xinping Ai Yongjin Fang Prof. Yuliang Cao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(10):e202316966
LiPF6 as a dominant lithium salt of electrolyte is widely used in commercial rechargeable lithium-ion batteries due to its well-balanced properties, including high solubility in organic solvents, good electrochemical stability, and high ionic conductivity. However, it suffers from several undesirable properties, such as high moisture sensitivity, thermal instability, and high cost. To address these issues, herein, we propose an electron-donation modulation (EDM) rule for the development of low-cost, sustainable, and electrochemically compatible LiNO3-based electrolytes. We employ high donor-number solvents (HDNSs) with strong electron-donation ability to dissolve LiNO3, while low donor-number solvents (LDNSs) with weak electron-donation ability are used to regulate the solvation structure to stabilize the electrolytes. As an example, we design the LiNO3-DMSO@PC electrolyte, where DMSO acts as an HDNS and PC serves as an LDNS. This electrolyte exhibits excellent electrochemical compatibility with graphite anodes, as well as the LiFePO4 and LiCoO2 cathodes, leading to stable cycling over 200 cycles. Through spectroscopy analyses and theoretical calculation, we uncover the underlying mechanism responsible for the stabilization of these electrolytes. Our findings provide valuable insights into the preparation of LiNO3-based electrolytes using the EDM rule, opening new avenues for the development of advanced electrolytes with versatile functions for sustainable rechargeable batteries. 相似文献