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991.
Chunhui Liu Dr. Chengyi Xiao Chengcheng Xie Qinglian Zhu Dr. Qiaomei Chen Prof. Wei Ma Prof. Weiwei Li 《Chemphyschem》2022,23(2):e202100725
Adding insulating polymers to conjugated polymers is an efficient strategy to tailor their mechanical properties for flexible organic electronics. In this work, we selected two insulating polymers as additives for high-performance photoactive layers and investigated the mechanical and photovoltaic properties in organic solar cells (OSCs). The insulating polymers were found to reduce the electron mobilities in the photoactive layers, and hence the power conversion efficiencies were significantly decreased. More importantly, we found that the insulating polymers exhibited negative effect on the mechanical properties of the photoactive layers, with reduced Young's modulus and low crack onset strains. Further studies revealed that the insulating polymers had poor miscibility with the photoactive layers, providing large domains and more cavities in blend thin films, which act as negative effect for the tensile test. The studies indicate that rational selection of insulating polymers, especially enhancing the non-covalent interaction with the photoactive layers, will be critically important for the stretchable OSCs. 相似文献
992.
Rechargeable Mg batteries (RMBs) are advantageous large-scale energy-storage devices because of the high abundance and high safety, but exploring high-performance cathodes remains the largest difficulty for their development. Compared with oxides and sulfides, selenides show better Mg-storage performance because the weaker interaction with the Mg2+ cation favors fast kinetics. Herein, nanorod-like FeSe2 was synthesized and investigated as a cathode for RMBs. Compared with microspheres and microparticles, nanorods exhibit higher capacity and better rate capability with a smaller particle size. The FeSe2 nanorods show a high capacity of 191 mAh g−1 at 50 mA g−1 and a good rate performance of 39 mAh g−1 at 1000 mA g−1. Ex situ characterizations demonstrate the Mg2+ intercalation mechanism for FeSe2, and a slight conversion reaction occurs on the surface of the particles. The capacity fading is mainly because of the dissolution of Fe2+, which is caused by the reaction between Fe2+ and Cl− of the electrolyte during the charge process on the surface of the particles. The surface of FeSe2 is mainly selenium after long cycling, which may also dissolve in the electrolyte during cycling. The present work develops a new type of Mg2+ intercalation cathode for RMBs. More importantly, the fading mechanism revealed herein has considered the specificity of Mg battery electrolyte and would assist a better understanding of selenide cathodes for RMBs. 相似文献
993.
Yurui Li Zhenning Ma Hongbo Guo Xiuli Xu Feng Zhang 《Journal of separation science》2022,45(13):2344-2355
A novel magnetic covalent organic framework was synthesized via a one-step coating approach with solvothermal reaction employing 2,4,6-tris(4-aminophen-yl)-1,3,5-triazine and 2,4,6-triformylphloroglucinol as two building blocks by covalent bonding. The prepared magnetic covalent organic frameworks were properly characterized by different techniques and employed as adsorbents of magnetic solid-phase extraction. An analytical method was developed for the simultaneous determination of five fungicides in two Chinese herbal medicine samples via magnetic solid-phase extraction coupled to ultra high performance liquid chromatography with tandem mass spectrometry analysis. Under optimized magnetic solid-phase extraction conditions, the method exhibited satisfactory recoveries (74.0−109.6%) with relative standard deviations of 0.4−4.6%, low limits of detection (0.003−0.015 μg/kg), and good linearity (R2 > 0.9960). Compared with the traditional extraction method, the proposed method required a lower amount of adsorbent (3 mg) and extraction time (5 min). The adsorbent also had favorable reusability (not less than eight times). Therefore, the magnetic covalent organic frameworks could be a promising adsorbent for the extraction and quantitation of fungicides in Chinese herbal medicines. 相似文献
994.
Yanqing Yang Joseph Cheramy Dr. Martin Brehm Prof. Dr. Yunjie Xu 《Chemphyschem》2022,23(11):e202200161
Raman and Raman Optical Activity (ROA) spectra of N-acetyl-L-cysteine (NALC), a flexible chiral molecule, were measured in water and in methanol to evaluate the solvent effects. Two different solvation approaches, that is, the DFT based “clusters-in-a-liquid” solvent model and the ab initio molecular dynamics (AIMD) simulations, were applied to simulate the Raman and ROA spectra. Systematic conformational searches were carried out using a recently developed conformational searching tool, CREST, with the inclusion of polarizable continuum model of water and of methanol. The CREST candidates of NALC and the NALC-solvent complexes were re-optimized and their Raman and ROA simulations were done at the B3LYP−D3BJ/def2-TZVP and the B3LYP-aug-cc-pVDZ//cc-pVTZ levels. Also, AIMD simulations, which includes some anharmonic effects and all intermolecular interactions in solution, were performed. By empirically weighting the computed Raman and ROA spectra of each conformer, good agreements with the experimental data were achieved with both approaches, while AIMD offered some improvements in the carbonyl and in the low wavenumber regions over the static DFT approach. The pros and cons of these two different approaches for accounting the solvent effects on Raman and ROA of this flexible chiral system will also be discussed. 相似文献
995.
Li Yongfeng Liu Mengyu Zheng Long Qu Zhipeng Xu Xiaochang Zhang Mingming Han Hongjiang Yang Zongju 《Journal of Solid State Electrochemistry》2022,26(10):2287-2299
Journal of Solid State Electrochemistry - Jet electrochemical deposition is a relatively new technology for selective electrochemical deposition. Its advantages include high deposition accuracy and... 相似文献
996.
Jiaming Zhang Yu Zhang Xiaoyu Liu Xiaolan Xu Yingchao Li Tianhong Zhang 《Journal of separation science》2022,45(4):968-975
Cinnarizine is a weak base, which can produce supersaturation and precipitation during gastrointestinal transit, affecting its absorption in vivo. Therefore, it is necessary to investigate whether the oral bioavailability of cinnarizine can be improved after co-administration with precipitation inhibitors or not. In order to evaluate the pharmacokinetic behavior of cinnarizine in rats, a simple, rapid, sensitive, and environmentally friendly supercritical fluid chromatography-tandem mass spectrometric method was established and validated. In this method, flunarizine, a structural analogue of cinnarizine, was selected as the internal standard, and cinnarizine was extracted from rat plasma using evaporation-free liquid–liquid extraction method. The analytes were separated on a Torus 1-AA column (3.0 mm × 100 mm, 1.7 μm) within 2.0 min, using a gradient elution procedure. The transitions of cinnarizine and flunarizine were m/z 369.1 → 167.1 and m/z 405.1 → 203.1, respectively. Cinnarizine showed good linear correlation in the range of 1–500 ng/ml with a lower limit of quantification of 1 ng/ml. The intra- and interday precision and accuracy of all quality control samples were within ±15%. This high-throughput, accurate, sensitive, and reproducible method has been successfully applied to study the effects of the precipitation inhibitor cinnarizine on the pharmacokinetics in rats. 相似文献
997.
Shuo Gu Tingting Mou Jian Chen Jing Wang Ying Zhang Meirong Cui Wenqian Hao Yue Sun Chengqin Zhang Tiantian Zhao Binbin Wei 《Journal of separation science》2022,45(10):1656-1671
Baihe-Dihuang Tang is a commonly prescribed remedy for depression. In this study, component screening with untargeted and targeted metabolomics was used to identify potential biomarkers for depression in chronic unpredictable mildly stressed rats. Using this novel identification method, the screening of organic acids, lily saponins, iridoids, and other ingredients formed the basis for subsequent metabolomics research. Baihe-Dihuang Tang supplementation in chronic unpredictable mild-stress-induced depression models, increased their body weight, sucrose preference, brain-derived neurotrophic factor deposition, and spatial exploring. Untargeted metabolomics revealed that Baihe-Dihuang Tang exerts its antidepressant effects by regulating the levels of lipids, organic acids, and its derivatives, and benzenoids in the brain, plasma, and urine of the depressed rats. Moreover, it also modulates the d -glutamine and d -glutamate metabolism and purine metabolism. Targeted metabolomics demonstrated significant reduction in l -glutamate levels in the brains of depressed rats. This could be a potential biomarker for depression. Baihe-Dihuang Tang alleviated depression by regulating the levels of l -glutamate, xanthine, and adenine in the brains of depressed rats. Together, these findings conclusively established the promising therapeutic effect of Baihe-Dihuang Tang on depression and also unraveled the underlying molecular mechanism of its potential antidepressant function. 相似文献
998.
Xiaoyan Cui Yujiao Wang Yumei Yan Zilin Meng Runhua Lu Haixiang Gao Canping Pan Xinlin Wei Wenfeng Zhou 《Journal of separation science》2022,45(4):908-918
In this study, a 4-formylphenylboronic acid-modified cross-linked chitosan magnetic nanoparticle (FPBA@CCHS@Fe3O4) was fabricated. The synthesized material was utilized as the magnetic solid-phase extraction adsorbent for the enrichment of six benzoylurea pesticides. In addition to B-N coordination, FPBA@CCHS@Fe3O4 interacts with benzoylureas through hydrogen bonds and π-π stacking interaction on account of rich active groups (amino and hydroxyl) and aromatic rings in structure. Compared to traditional extraction methods, less adsorbent (20 mg) and reduced extraction time (3 min) were achieved. The adsorbent also exhibited good reusability (no less than 10 times). Coupled with a high-performance liquid chromatography–diode array detector, satisfactory recoveries (89.1–103.9%) and an acceptable limit of detection (0.2–0.7 μg/L) were obtained. Under optimized conditions, the established method was successfully applied to the tea infusion samples from six major tea categories with acceptable recoveries ranging from 76.8 to 110%, indicating its application potential for the quantitative detection of pesticides in complex matrices. 相似文献
999.
Telin Zhu Peipei Qi Jiao Wang Shanshan Di Zhiwei Wang Hao Xu Huiyu Zhao Qiang Wang Xinquan Wang Chenghui Zhang 《Journal of separation science》2022,45(7):1326-1335
Many plants have a high polyphenol content, which causes the matrix effect and makes the analysis of trace pesticide residues highly challenging. A common approach to improving matrix effects is to purify pesticides through the use of sorbents, but this requires a combination of multiple sorbents and extensive use. Zeolitic imidazolate framework-8 is widely used for pesticide analysis due to its high porosity, large specific surface area, and versatility. Here, we established and validated a modified quick, easy, cheap, effective, rugged, and safe method based on a zeolitic imidazolate framework-8 that was used to test the removal ability for polyphenols. To this end, 145 pesticide residues in peppermint, perilla, fennel, and mulberry leaves were analyzed by the modified method coupled with liquid chromatography with tandem mass spectrometry. The mean recoveries of all pesticide residues were in the range of 74.3–103.7%, with mean relative standard deviations ≤9.1% at spiked concentrations of 1, 10, 50, and 100 μg/kg for mulberry leaves. The limits of quantitation of the method ranged from 1 to 50 μg/kg. This study offers a reliable approach for the accurate quantitative analysis of various trace substances in the polyphenol-rich plants. 相似文献
1000.
Delocalized \begin{document}$\pi_3^6$\end{document} Bond in OX\begin{document}$_2$\end{document} (X=Halogen) Molecules 下载免费PDF全文
Yi-han Tang Pu Yang Meng-yuan Chen Yu-ru Wang Jia-xin Wang Jia-wei Xu 《化学物理学报(中文版)》2022,35(3):542-550
OX\begin{document}$_2$\end{document} (X=halogen) molecules was studied theoretically. Calculation results show that delocalized \begin{document}$\pi_3^6$\end{document} bonds exist in their electronic structures and O atoms adopt the sp\begin{document}$^2$\end{document} type of hybridization, which violates the prediction of the valence shell electron pair repulsion theory of sp\begin{document}$^3$\end{document} type. Delocalization stabilization energy is proposed to measure the contribution of delocalized \begin{document}$\pi_3^6$\end{document} bond to energy decrease and proves to bring extra-stability to the molecule. These phenomena can be summarized as a kind of coordinating effect. 相似文献