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101.
Weinan Zhao Yi Wang Mei Han Dr. Jiaxin Xu Prof. Dr. Kam Chiu Tam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(68):e202202657
Superhydrophobic surfaces with expanded wetting behaviors, like tunable adhesion, hybrid surface hydrophobicity and smart hydrophobic switching have attracted increasing attention due to their broad applications. Herein, the construction methods, mechanisms and advanced applications of special superhydrophobicity are reviewed, and hydro/superhydrophobic modifications are categorized and discussed based on their surface chemistry, and topographic design. The formation and maintenance of special superhydrophobicity in the metastable state are also examined and explored. In addition, particular attention is paid to the use of special wettability in various applications, such as membrane distillation, droplet-based electricity generators and anti-fogging surfaces. Finally, the challenges for practical applications and future research directions are discussed. 相似文献
102.
We analyze a class of numerical schemes proposed [26] for stochastic differential equations with multiple time scales. Both advective and diffusive time scales are considered. Weak as well as strong convergence theorems are proven. Most of our results are optimal. They in turn allow us to provide a thorough discussion on the efficiency as well as optimal strategy for the method. © 2005 Wiley Periodicals, Inc. 相似文献
103.
104.
Xiang Zhao Xuan Qiu Haodong Xue Si Liu Dingli Liang Chuan Yan Weinan Chen Prof. Yonggang Wang Prof. Gang Zhou 《Angewandte Chemie (International ed. in English)》2023,62(9):e202216713
Organic p-type cathode materials have recently attracted increasing attention due to their higher redox potentials and rate capabilities in comparison to n-type cathodes. However, most of the p-type cathodes based on one-electron redox still suffer from limited stability and low specific capacity (<150 mAh g−1). Herein, two polymers, conjugated poly(diethyldihydrophenazine vinylene) ( CPP ) and non-conjugated poly(diethyldihydrophenazine ethylidene) ( NCPP ) containing two-electron redox dihydrophenazine, have been developed as p-type cathode materials. It is experimentally and theoretically found that the conjugated linkage among the redox centers in polymer CPP is more favorable for the effective charge delocalization on the conjugated polymer backbone and the sufficient oxidation in the higher potential region (3.3–4.2 V vs. Li/Li+). Consequently, the CPP cathode displays a higher reversible specific capacity of 184 mAh g−1 with excellent cycling stability. 相似文献
105.
Hyper-Raman spectra were obtained for zinc phthalocyanine in a dilute pyridine solution at excitation wavelengths that are two-photon resonant with the one-photon-allowed B band (360-380 nm) as well as with the two-photon absorption near 440 nm reported by Drobizhev et al. ( J. Chem. Phys. 2006, 124, 224701 ). In both regions, the hyper-Raman spectra were very different from the linear resonance Raman spectra at the corresponding excitation frequencies. While the resonance Raman spectra show only g symmetry modes, almost all of the hyper-Raman frequencies can be assigned as fundamentals of E u symmetry that also are observed in the infrared absorption spectrum or E u symmetry combination bands. These results contrast sharply with previous observations of highly noncentrosymmetric push-pull conjugated molecules and are consistent with a structure for phthalocyanine in solution that is centrosymmetric or nearly so. The hyper-Raman spectra show different intensity patterns in the two excitation regions, consistent with different Franck-Condon and/or vibronic coupling matrix elements for the different resonant states. 相似文献
106.
Matthias A. Ruderer Ezzeldin Metwalli Dr. Weinan Wang Gunar Kaune Stephan V. Roth Dr. Peter Müller‐Buschbaum Prof. Dr. 《Chemphyschem》2009,10(4):664-671
Photoactive polymer blends: Films consisting of two photoactive homopolymers, MEH‐PPV and P3HT, are prepared via spin coating. Investigation of the lateral domain distance inside the blended film, performed by using grazing incidence small angle X‐ray scattering techniques, shows that the theoretically predicted blending ratio seems most promising (see figure).
107.
ABSTRACTA method to estimate the absorbance spectrum caused by the variation in the concentration of a substance in a medium at the optimum pathlength for every wavelength on a wide waveband without adjusting the cell’s size precisely was presented in the paper. This spectrum could be used to evaluate the absorption of certain substance at the optimum pathlength at each wavelength, instead of using a uniform pathlength like absorption coefficient. And the absorbance spectra of glucose in aqueous solution at optimum pathlength for every wavelength at 900–2500?nm were estimated by using this method. Moreover, the glucose absorbance spectra show an unexpected result that the absorption peaks at different overtones of the oxygen–hydrogen and carbon–hydrogen bonds are of similar amplitudes. 相似文献
108.
P. Palffy-Muhoray T. Kosa Weinan E 《Applied Physics A: Materials Science & Processing》2002,75(2):293-300
Light can change the orientation of liquid-crystal molecules. Usually, the torque that causes the reorientation originates
in angular-momentum transfer from the radiation field to the material. If a small amount of dichroic dye is dissolved in the
liquid crystal, a light-induced torque can appear essentially without the transfer of angular momentum from light. We show
that, in such cases, the dye molecules act as light-driven molecular motors which, via an orientational Brownian ratchet mechanism,
transfer angular momentum, which originates at the cell walls, to the liquid crystal. Understanding the details of this mechanism
is important for applications ranging from flat-panel displays to optomechanical transducers.
Received: 20 October 2001 / Accepted: 14 January 2002 / Published online: 22 April 2002 相似文献
109.
Finite temperature string method for the study of rare events 总被引:1,自引:0,他引:1
A method is presented for the study of rare events such as conformational changes arising in activated processes whose reaction coordinate is not known beforehand and for which the assumptions of transition state theory are invalid. The method samples the energy landscape adaptively and determines the isoprobability surfaces for the transition: by definition the trajectories initiated anywhere on one of these surfaces has equal probability to reach first one metastable set rather than the other. Upon weighting these surfaces by the equilibrium probability distribution, one obtains an effective transition pathway, i.e., a tube in configuration space inside which conformational changes occur with high probability, and the associated rate. The method is first validated on a simple two-dimensional example; then it is applied to a model of solid-solid transformation of a condensed system. 相似文献
110.
Yuming Zhou Weinan Leng Xiaojuan Liu Qunhua Xu Jikang Feng Juzheng Liu 《Journal of polymer science. Part A, Polymer chemistry》2002,40(14):2478-2486
Some thermally stable second‐order nonlinear optical (NLO) polyimides were synthesized. The polyimides were prepared by the ring‐opening polyaddition of 4,4′‐(hexafluoroisopropylidene) diphthalic anhydride and pyromellitic dianhydride with two aromatic azodiamine derivatives as the NLO chromophores. These chromophores, based on a nitro group connected with azobenzene as the acceptor end of a donor–π‐bridge–acceptor chromophore and a diamine group as the donor end, had specific chemical stability. On the basis of ZERNER'S INDO methods, according to the sum‐over‐states formula, a program for the calculation of nonlinear second‐order optical susceptibilities was devised. The resulting polyimides had high number‐average and weight‐average molecular weights of up to 26,000 and 53,500, respectively, and a large glass‐transition temperature of 248 °C. With an in situ poling and temperature ramping technique, the optimal temperatures (Topt's) for corona poling were obtained for the largest second‐order NLO response. The electrooptic coefficient (γ33) of a polyimide at a wavelength of 830 nm was up to 21 pm/V after corona poling under its Topt, and the value remained at elevated temperatures (>90.6% was retained at 240 °C for >120 h). The thermal stability of the NLO polyimides was studied with UV spectrometry after poling of the films. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2478–2486, 2002 相似文献