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21.
Bohuai Xiao Jianqiao Dong Zhiye Wang Xu Wang Mingjun Sun Jing Guo Gongming Qian Yunchuan Li Shuai Chang 《Chemphyschem》2022,23(7):e202100833
One important prerequisite for the fabrication of molecular functional device strongly relies on the understanding the conducting behaviors of the metal-molecule-metal junction that can respond to an external stimulus. The model Lewis basic molecule 4,4′-(pyridine-3,5-diyl)dibenzonitrile (DBP), which can react with Lewis acid and protic acid, was synthesized. Then, the molecular conducting behavior of DBP, DBP-B(C6F5)3, and DBP-TfOH (DBP-B(C6F5)3, and DBP-TfOH were produced by Lewis acid and protonic acid treatment of DBP) was researched and compared. Given that their identical physical paths for DBP, DBP-B(C6F5)3, and DBP-TfOH to sustain charge transport, our results indicate that modifying the molecular electronic structure, even not directly changing the conductive physical backbone, can tune the charge transporting ability by nearly one order of magnitude. Furthermore, the addition of another Lewis base triethylamine (of stronger alkaline than DBP), to Lewis acid-base pair reverts the electrical properties back to that of a single DBP junction, that is constructive to propose a useful but simple strategy for the design and construction of reversible and controllable molecular device based on pyridine derived molecule. 相似文献
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23.
Jia Tian-Cong Guo Jin-Tao Wang Zhen Zhu Xiao-Shan Zhang Qian-Xin Chen Ping Yao Kun Lv Wen-Ying Liu Guo-Guang 《Journal of Radioanalytical and Nuclear Chemistry》2019,321(3):823-829
Journal of Radioanalytical and Nuclear Chemistry - In the present work the final products of coumarin radiation chemical transformation are investigated by chromatography. During radiolysis of... 相似文献
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26.
Wu Fang Guo Xiaoxue Hao Gazi Hu Yubing Jiang Wei 《Journal of Solid State Electrochemistry》2019,23(9):2627-2637
Journal of Solid State Electrochemistry - Developing low-cost and earth-abundant electrocatalysts with high activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER)... 相似文献
27.
Han Jing Sun Youhong Guo Wei Deng Sunhua Hou Chuanbin Qu Lili Li Qiang 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2287-2296
Journal of Thermal Analysis and Calorimetry - In this study, the non-isothermal pyrolysis method was used to investigate the pyrolysis characteristics of oil shale from four areas: namely Nongan,... 相似文献
28.
Zhou Shuiping Zhou Xiaoyang Tang Gen Guo Xiang Pang Aimin 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2529-2540
Journal of Thermal Analysis and Calorimetry - Differences of thermal decomposition characteristics and combustion properties between CL-20-based propellants and HMX-based propellants were... 相似文献
29.
Mohit Jaiswal Trang T. Tran Qingjiang Li Xin Yan Mingwei Zhou Krishnendu Kundu Gail E. Fanucci Zhongwu Guo 《Chemical science》2020,11(46):12522
Metabolic glycan engineering (MGE) coupled with nitroxide spin-labeling (SL) was utilized to investigate the heterogeneous environment of cell surface glycans in select cancer and normal cells. This approach exploited the incorporation of azides into cell surface glycans followed by a click reaction with a new nitroxide spin label. Both sialic acid and N-acetylglucosamine (GlcNAc) were targeted for spin labelling. Although each of these moieties experiences a diverse and heterogeneous glycan environment, their EPR spectra and hence mobility are both characterized as a linear combination of two distinct spectra where one component reflects a highly mobile or uncrowded micro-environment with the second component reflecting more restricted motion, reflective of increased crowding and packing within the glycocalyx. What differs among the spectra of the targeted glycans is the relative percentage of each component, with sialic acid moieties experiencing on average an ∼80% less crowded environment, where conversely GlcNAc/GalNAz labeled sites reported on average a ∼50% more crowded environment. These distinct environments are consistent with the organization of sugar moieties within cellular glycans where some residues occur close to the cell membrane/protein backbone (i.e. more restricted) and others are more terminal in the glycan (i.e. more mobile). Strikingly, different cell lines displayed varied relative populations of these two components, suggesting distinctive glycan packing, organization, and composition of different cells. This work demonstrates the capability of SDSL EPR to be a broadly useful tool for studying glycans on cells, and interpretation of the results provides insights for distinguishing the differences and changes in the local organization and heterogeneity of the cellular glycocalyx.Metabolic glycan engineering (MGE) coupled with nitroxide spin-labeling (SL) was utilized to investigate the heterogeneous environment of cell surface glycans in select cancer and normal cells. 相似文献
30.
Marie‐Claire Giel Christopher J. Smedley Emily R. R. Mackie Taijie Guo Jiajia Dong Tatiana P. Soares da Costa John E. Moses 《Angewandte Chemie (International ed. in English)》2020,59(3):1181-1186
The boom in growth of 1,4‐disubstituted triazole products, in particular, since the early 2000’s, can be largely attributed to the birth of click chemistry and the discovery of the CuI‐catalyzed azide–alkyne cycloaddition (CuAAC). Yet the synthesis of relatively simple, albeit important, 1‐substituted‐1,2,3‐triazoles has been surprisingly more challenging. Reported here is a straightforward and scalable click‐inspired protocol for the synthesis of 1‐substituted‐1,2,3‐triazoles from organic azides and the bench stable acetylene surrogate ethenesulfonyl fluoride (ESF). The new transformation tolerates a wide selection of substrates and proceeds smoothly under metal‐free conditions to give the products in excellent yield. Under controlled acidic conditions, the 1‐substituted‐1,2,3‐triazole products undergo a Michael addition reaction with a second equivalent of ESF to give the unprecedented 1‐substituted triazolium sulfonyl fluoride salts. 相似文献