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111.
Recently pattern formation in layered structures, showing complicated superimposed patterns, has been modeled by coupling two Turing systems linearly, i.e., passively, such that the characteristic length scales of the independent systems are well separated. Here we propose a model of two non-linearly coupled Turing systems to study pattern formation in layered membrane-like structures, where the coupling plays an active role and changes the kinetics of the uncoupled systems. Extensive numerical simulations show that non-linear coupling generates a number of new regular patterns different from the ones observed earlier with linearly coupled systems. Some of them turn out to be superimposed patterns with different length scales, but many are not. Also, contrary to the linear coupling case, the strength of the non-linear coupling is found to play an important role in the formation and selection of patterns. 相似文献
112.
We have performed first-principles calculations using full-potential augmented-plane-wave method to investigate the fundamental properties of the Cd1–xZnxTe alloys. The composition dependence of the lattice constant and the bulk modulus have been estimated from total energy calculations. By means of the analytical fitting the band structures in the vicinity of the Brillouin center a complete set of effective electron- and hole-masses have also been derived. In order to further understand the effects of the chemical bonding on the above macroscopic properties we then studied the relaxation behaviors and the changes of the electronic states upon alloying for x=0.25 system. The results presented here yield a general understanding of the fundamental properties for the Cd1–xZnxTe crystals studies. 相似文献
113.
Jienan Li Lin Lin Bowei Jiang Chudong Wang Moutanou Modeste Judes Zeye Dan Wen Wei He Weifeng Qu Ying Liu Lagabaiyila Zha 《Electrophoresis》2021,42(9-10):1143-1152
DNA genotyping from trace and highly degraded biological samples is one of the most significant challenges of forensic DNA identification. There is a lack of simple and effective methods for genotyping highly degraded samples. In this study, a multiple loci insertion/deletion polymorphisms (Multi-InDels) panel was designed for detecting 18 autosomal Multi-InDels through capillary electrophoresis (CE) with amplicon sizes no longer than 125 bp. Studies of sensitivity, degradation, and species specificity were performed and a population study was carried out using 192 samples from Han populations in Hunan province in the south of China. The combined random match probability (CMP) of these 18 Multi-InDels was 3.23 × 10–12 and the cumulative probability of exclusion (CPE) was 0.9989, suggesting this panel could be used independently for human identification and could provide efficient supporting information for parentage testing. Complete profiles were obtained from as low as 62.5 pg of total input DNA after increasing the number of PCR cycles. Moreover, all alleles were detected from artificially highly degraded DNA after 80 min of boiling water bath treatment. This 18 Multi-InDels panel is simple, fast, and effective for the forensic analysis of highly degraded DNA. 相似文献
114.
115.
Dr. Sven O. Krabbenborg Prof. Dr. Jurriaan Huskens 《Angewandte Chemie (International ed. in English)》2014,53(35):9152-9167
This review surveys recent developments in the field of electrochemically generated gradients. The gradual variation of properties, which is a key characteristic of gradients, is of eminent importance in technology, for example, directional wetting, as well as biology, for example, chemotaxis. Electrochemical techniques offer many benefits, such as the generation of dynamic solution and surface gradients, integration with electronics, and compatibility with automation. An overview is given of newly developed methods, from purely electrochemical techniques to the combination of electrochemistry with other methods. Electrochemically fabricated gradients are employed extensively for biological and technological applications, such as high‐throughput screening, high‐throughput deposition, and device development, all of which are covered herein. Especially promising are developments towards the study and control of dynamic phenomena, such as the directional motion of molecules, droplets, and cells. 相似文献
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117.
In this work, we demonstrate an in situ phase conversion from basic magnesium chloride(BMC) into magnesium hydroxide whisker by using polar organic solvent at low temperature. The morphology and phase composition of magnesium hydroxide whiskers prepared at different reaction temperature, alkali concentration and organic solvent were analyzed by X-ray diffraction(XRD) and scanning electronic microscope(SEM). It was found that when one of the organic solvents such as absolute ethyl alcohol, butanol, polyethylene glycol(PEG-400), acetone, et al. was selected as the template, the precursor BMC can transform into whisker-like magnesium hydroxide through precipitate transformation in low temperature and non-hydrothermal system. It can be reasonably explained that the regulation of Mg^2+ solubility by those organic solvents and the sustained release of Mg^2+ dissolution by organic adsorption played a significant role in the formation of magnesium hydroxide whisker via BMC whisker as the precursor. 相似文献
118.
Dr. Guobin Wen Dr. Bohua Ren Dr. Moon G. Park Dr. Jie Yang Dr. Haozhen Dou Dr. Zhen Zhang Dr. Ya-Ping Deng Prof. Zhengyu Bai Prof. Lin Yang Prof. Jeff Gostick Prof. Gianluigi A. Botton Prof. Yongfeng Hu Prof. Zhongwei Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12960-12967
Simultaneously improving energy efficiency (EE) and material stability in electrochemical CO2 conversion remains an unsolved challenge. Among a series of ternary Sn-Ti-O electrocatalysts, 3D ordered mesoporous (3DOM) Sn0.3Ti0.7O2 achieves a trade-off between active-site exposure and structural stability, demonstrating up to 71.5 % half-cell EE over 200 hours, and a 94.5 % Faradaic efficiency for CO at an overpotential as low as 430 mV. DFT and X-ray absorption fine structure analyses reveal an electron density reconfiguration in the Sn-Ti-O system. A downshift of the orbital band center of Sn and a charge depletion of Ti collectively facilitate the dissociative adsorption of the desired intermediate COOH* for CO formation. It is also beneficial in maintaining a local alkaline environment to suppress H2 and formate formation, and in stabilizing oxygen atoms to prolong durability. These findings provide a new strategy in materials design for efficient CO2 conversion and beyond. 相似文献
119.
Dr. Min Luo Dr. Chensheng Lin Donghong Lin Prof. Ning Ye 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16112-16115
The first fluorosulfonic ultraviolet (UV) nonlinear optical (NLO) material, C(NH2)3SO3F, is rationally designed by taking KBe2BO3F2 (KBBF) as the parent compound. C(NH2)3SO3F features similar topological layers as KBBF by replacing inorganic (BO3)3− with organic C(NH2)3+ trigonal units and BeO3F with SO3F− tetrahedra. Therefore, C(NH2)3SO3F is a metal-free UV NLO crystal. Benefiting from the coplanar configuration of the C(NH2)3+ cationic groups, it possesses a large SHG response of 5×KDP and moderate birefringence of 0.133@1064 nm. Besides, it has a short UV cutoff edge of 200 nm. The calculated results reveal the shortest SHG phase-matching wavelengths can reach 200 nm. These findings highlight the exploration of metal-free compounds as nontoxic and low-cost UV NLO materials as a new research area. 相似文献
120.