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971.
In order to explore the role of fluorine atoms on photostability as well as morphology control of active layer in the presence of 1,4‐butanedithiol (BT), the four polymers with or without fluorine atoms in the backbones including polythieno[3,4‐b]thiophene/benzodithiophene, poly[(4,8‐bis‐(2‐ethylhexyloxy)‐benzo(1,2‐b:4,5‐b9)dithiophene)‐2,6‐diyl‐alt‐(4‐(2‐ethylhexanoyl)‐thieno[3,4‐b]thiophene‐)‐2‐6‐diyl)], poly[4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b;4,5‐b′]dithiophene‐2,6‐diyl‐alt‐(4‐(2‐ethylhexyl)‐3‐fluorothieno[3,4‐b]thiophene‐)‐2‐carboxylate‐2‐6‐diyl)], and poly[4,8‐bis‐(2‐ethyl‐hexyl‐thiophene‐5‐yl)‐benzo[1,2‐b:4,5‐b0]dithiophene‐2,6‐diyl]‐alt‐[2‐(20‐ethyl‐hexanoyl)‐thieno [3,4‐b]thiophen‐4,6‐diyl] were selected for comparison. It is found that the specimens containing fluorine atoms in polymer backbones showed of higher stability after illumination for 1 h in the presence of BT additive, contributing to the higher domain purity. The specific interaction between fluorine atoms and thiol groups was demonstrated by the appearance of novel absorption peak at 2663.1 cm?1, in addition to the broadening of peak at 2556.2 cm?1 ascribing to S? H stretching vibration as confirmed by Fourier transform infrared (FTIR) spectroscopy. The finding may guide the accurate use of thiols as effective solvent additive in morphology and stability optimization. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 941–951  相似文献   
972.
973.
974.
Charge transport across the peptide chains is one of the vital processes in the biological systems, so understanding their charge transport properties is an indispensable prerequisite to explain the complex biochemical phenomenon. Here, we review the charge transport mechanism, the influence of the special groups and the experimental conditions on the charge transport through the peptide backbone by employing the single‐molecule electrical measurements. Besides, we further review the recent progresses in charge transport properties of supramolecular interaction among the adjacent peptide chains. Finally, we discuss some experimental and theoretical contradictions existing in the charge transport through peptides and provide new inspiration for the future development of the bioelectronics at the single‐molecule scale.  相似文献   
975.
We demonstrated a method to pattern catalyst via inkjet printing to grow SWNTs, using metal salt solutions as the inks and an ordinary office-use printer. We printed water solutions of cobalt acetate on hydrophilic Si substrates and grew high quality SWNT films.  相似文献   
976.
Germanium dioxide (GeO2) aqueous solutions are facilely prepared and the corresponding anode buffer layers (ABLs) with solution process are demonstrated. Atomic force microscopy, X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy measurements show that solution-processed GeO2 behaves superior film morphology and enhanced work function. Using GeO2 as ABL of organic light-emitting diodes (OLEDs), the visible device with tris(8-hydroxy-quinolinato)aluminium as emitter gives maximum luminous efficiency of 6.5 cd/A and power efficiency of 3.5 lm/W, the ultraviolet device with 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole as emitter exhibits short-wavelength emission with peak of 376 nm, full-width at half-maximum of 42 nm, maximum radiance of 3.36 mW/cm2 and external quantum efficiency of 1.5%. The performances are almost comparable to the counterparts with poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) as ABL. The current, impedance, phase and capacitance as a function of voltage characteristics elucidate that the GeO2 ABL formed from appropriate concentration of GeO2 aqueous solution favors hole injection enhancement and accordingly promoting device performance.  相似文献   
977.
Li  S. K.  Huang  L. L.  Lv  Y. D.  Feng  H. D. 《Russian Journal of Organic Chemistry》2019,55(9):1432-1438
Russian Journal of Organic Chemistry - A rapid and efficient catalytic approach has been proposed for the synthesis of dimethyl 2-[2-(aryl-amino)but-3-en-1-yl]- and...  相似文献   
978.
The interactions between bovine serum albumin (BSA) and polymer (poly (METAC-co-NIPAm-co-Eu(AA)3Phen), PMNEu) containing rare earth element (Europium) were detailedly investigated by both of experimental techniques, such as fluorescence spectroscopic analysis, zeta-potential characterization, hydrodynamic size measurements and transmission electron microscopy (TEM) observation, and theoretical calculations. As a result, we concluded that PMNEu could interact with BSA through electrostatic force and quench the fluorescence of BSA, which was regarded as the static quenching mechanism. In addition, the binding constant and binding sites number of BSA with PMNEu were calculated, and the distance between PMNEu and BSA was also estimated to be 1.9?nm based on Föster’s theory. Furthermore, the two fluorescence peaks of PMNEu at 594?nm and 618?nm were detected, and the density of them increased with the more BSA being added to couple with PMNEu. Additionally, The zeta-potential results confirmed the electrostatic interaction mode between BSA and PMNEu, which was concluded with the previous thermodynamic analysis. At last, the results from the hydrodynamic size measurement had a good agreement with those from the TEM observation about the structure and size variation during the complexation of PMNEu with different concentrations of BSA.  相似文献   
979.
Zhang  Yi  Wang  Xiaohui  Feng  Wei  Zhen  Yichao  Zhao  Peiyao  Li  Longtu  Cai  Ziming 《Journal of Solid State Electrochemistry》2019,23(3):749-758
Journal of Solid State Electrochemistry - For all-solid-state lithium-ion batteries, several disadvantages such as low ionic conductivity and poor interfacial stability have been concerned....  相似文献   
980.
Zhou  Jiahui  Jiang  Feng  Li  Sijie  Xu  Zhijie  Sun  Wei  Ji  Xiaobo  Yang  Yue 《Journal of Solid State Electrochemistry》2019,23(7):1991-2000
Journal of Solid State Electrochemistry - Considering serious pollution from the traditional chemical synthesis process, the resource-rich, clean electrode materials are greatly desired....  相似文献   
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