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991.
Junfeng Li Xuelei Peng Chenxi Hou Shunan Shi Jiamian Ma Qi Qi Wen-Yong Lai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(63):e202202336
Molecular motions are closely associated with the behaviors and properties of organic materials. However, monitoring molecular motions is challenging. Herein, a chiral supramolecular system consisting of L-/D-phenylalanine (LPF/DPF) as a chiral inducer and an achiral tetraphenylethene derivative (TPEF) as a molecular rotor has been proposed and explored for real-time discriminating the supramolecular motions by the visualization of circularly polarized luminescence (CPL) signal variations. Derived from the ordered molecular motions of TPEF induced by LPF/DPF, highly organized aggregates have been progressively assembled in a controlled manner with differentiated morphologies, including spherical particles, one-dimensional fibers, and floor-shaped supercrystals. Notably, increasing level of ordered aggregates, in turn, led to quenching emissions, while the CPL signals have been dramatically amplified accompanying by a sharp enhancement of luminescence dissymmetry factors (glum) from nearly 0 to −0.1. The significant amplification of CPL is attributed to the ordered aggregates of supramolecules, leading to the decrease of electric transition dipole moments in supramolecular system. As a result of the chiral supramolecular motions powered by supramolecular crystallization, the supramolecular motions are conveniently discriminated by visual CPL signal variation with an enhancement of glum value from 0 to −0.1 in real time. 相似文献
992.
Yang Chao Liu Xinjie Yang Kai Lai Yanqing Zhang Kai Tian Zhongliang 《Journal of Solid State Electrochemistry》2021,25(2):611-616
Journal of Solid State Electrochemistry - The effects of hydrogen evolution reaction on the deformation of zinc anode which cycles at nearly 100% depth of discharge (DOD) are studied. Results show... 相似文献
993.
Chunhua Hu Shaoyong Lai Zheng Dou 《Journal of Difference Equations and Applications》2019,25(3):351-372
A rational expectation model with lagged endogenous variables is used to describe how the current price level is influenced by the expectation and historic price level. The time domain of the rational expectation model is extended to a complex discrete time domain which is a collection of points along the real number line. The rational expectation model with lagged endogenous variables is solved in multi-dimensional cases where the agents possess multiple assets, and the current price of each asset is related to the expected price and historical prices. An example about price determination process of storable commodities is given to illustrate the advantages of the rational expectation model on isolate time domain. 相似文献
994.
Po-Ni Lai Prof. Thomas S. Teets 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(23):6026-6037
In this work, a series of ten new red-emitting heteroleptic iridium(III) complexes of the type Ir(C^N)2(L^X) (C^N=cyclometalating ligand, L^X=monoanionic chelating ancillary ligand) is introduced. The suite of new complexes includes two different cyclometalating ligands and five different ancillary ligands, with the primary goal of investigating the effect of the ancillary ligand structure on the excited-state dynamics. The structural variety of the ancillary ligands permitted investigations of the effects of donor atom identity, chelate ring size, and substituents on the electronic structure and excited state properties. Electrochemical analysis showed that the ancillary ligand has a substantial effect on the energy of the HOMO, whereas the LUMO is left unperturbed. Photoluminescence spectra showed that the ancillary ligand can sometimes strongly influence the emission wavelength, but in all cases is an important determinant of the excited-state dynamics. 相似文献
995.
996.
Li‐Hong Zhang Tao Jiang Dr. Lian‐Bin Wu Dr. Jun‐Hua Wan Dr. Chih‐Hsien Chen Dr. Yong‐Bing Pei Dr. Hua Lu Yuan Deng Gao‐Feng Bian Prof. Hua‐Yu Qiu Prof. Guo‐Qiao Lai 《化学:亚洲杂志》2012,7(7):1583-1593
A series of linear 2,5‐tetraphenylsilole‐vinylene‐type polymers were successfully synthesized for the first time. The tetraphenylsilole moieties were linked at their 2,5‐positions through a vinylene bridge with p‐dialkoxybenzenes to obtain polymer PSVB and with 3,6‐carbazole to obtain polymer PSVC . For comparison, 2,5‐tetraphenylsilole‐ethyne‐type polymer PSEB was also synthesized, in which the vinylene bridge of PSVB was replaced with an ethyne bridge. Very interestingly, the bridging group (vinylene or ethyne) had a significant effect on the photophysical properties of the corresponding polymers. The fluorescence peak of PSEB at 504 nm in solution originated from the emission of its silole moieties, whereas PSVB and PSVC emitted yellow light and no blueish–green emission from the silole moieties was observed, thus demonstrating that the emissions of PSVB and PSVC were due to their polymer backbones. More importantly, the 2,5‐tetraphenylsilole‐ethyne polymer exhibited a pronounced aggregation‐enhanced emission (AEE) effect but the 2,5‐tetraphenylsilole‐vinylene polymer was AEE‐inactive. Moreover, both AEE‐active 2,5‐tetraphenylsilole‐ethyne polymer and AEE‐inactive 2,5‐tetraphenylsilole‐vinylene polymers were successfully applied as fluorescent chemosensors for the detection of explosive compounds. 相似文献
997.
998.
999.
Hu Yue Zhi Meiting Zeng Ziqing Lu Wenguan Lai Yinlong Wang Xiaobing 《Research on Chemical Intermediates》2022,48(3):935-948
Research on Chemical Intermediates - In this study, the removal of Cr(VI) using commercial FeS with the partially oxidized surface was investigated under visible light. The results demonstrated... 相似文献
1000.
A simple, robust, and accurate HLLC-type Riemann solver for the compressible Euler equations at various Mach numbers is built. To cure shock instability of the HLLC solver at strong shocks, a pressure-control technique, which plays a role in limiting the propagation of erroneous pressure perturbation, is proposed. With an all Mach correction method for the compressible Euler system, the proposed method is further extended to compute flow problems at low Mach numbers. The proposed all Mach HLLC-type scheme has been implemented and used to compute a variety of flow problems ranging from hypersonic compressible to low Mach incompressible flow regimes. Various numerical results demonstrate that the obtained all Mach HLLC-type scheme is both accurate and stable for all speed ranges. 相似文献