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Low‐band gap semiconductor polymer materials play a crucial role in the field of organic optoelectronics. In this context, a series of low‐band gap polymers containing thienopyrazine as the acceptor and cyclofluorene–bithiophene as the donor were synthesized and utilized in resistive random access memory (RRAM) devices. These memory devices consistently exhibit nonvolatile flash memory behavior. Remarkably, all three polymers demonstrate stability even after 1000 cycles without significant fluctuations. Notably, the three polymer‐based devices also exhibit excellent ternary memory performance, with current ratios of 1:102.8:104, 1:101.3:103.9, and 1:101.8:103.6. Furthermore, the photoelectric properties of the three polymers and the conduction mechanisms of the memory devices were thoroughly discussed. [ABSTRACT FROM AUTHOR]

Based on the performance of improving the stabilities and coloring efficiencies of triphenylamine polymers, this paper separately synthesized different diamines and 3,4‐dimethylthieno[2,3‐b]thiophene‐2,5‐dicarboxylic acid, and the electrochromic functions of the polymer films were studied on indium‐tin oxide glass (ITO) glass. The polymers had a thiophene group, which was rich in π‐electrons and conducive to molecular stability, and showed good stabilities. Ultraviolet spectrum showed that all the six polymers had a wide absorption band in the neutral range of 200–700 nm. Electrochromic analysis showed that the six kinds of polymer films all showed reasonable optical contrast, short response time and low band gap in the infrared spectrum range of 200–1000 nm. Among them, the film formed by PAD2 on ITO glass had better electrochromic properties, longer bleaching response time (tc = 1.3 s, tb = 4.1 s), PAD3 had better coloration efficiency (214 cm2 C−1). [ABSTRACT FROM AUTHOR]

The development prospect of conductive electrochromic (EC) polymers requires the design of polymers with high performance and good stability. Here, a new scheme is designed to enhance EC properties by adjusting the monomer molecular structure. Four monomers with different structures based on thiophene and 3,4‐ethylenedioxythiophene (EDOT) are designed and synthesized. The corresponding polymer films (P1, P2, P3, and P4) are prepared by electrochemical polymerization at low applied potential. The spatial structure–performance relationship of precursors with different structures and polymers is systematically discussed. In the electropolymerization experiments, it is noted that P3 has no EC property. This may be connected to the spatial structure of P3 polymerization which is not suitable for charge transporting. By contrast, the other three polymers exhibit excellent electrochemical properties. The diffusion rate higher of P1 has also been corroborated by using electrochemical impedance spectroscopy (EIS) spectrum. The P1 film has the best stability and fastest colorized time among the samples; such superior electrochemical property may be associated with the closely stacked formed by the unique sheet‐like spatial structure. The design of the space structure has a significant impact on the optical and electrical properties of the polymer film. [ABSTRACT FROM AUTHOR]

Two donor units (D)‐acceptor units (A) type monomers were synthesized by Stille coupling reaction, and then three D‐A type hybrid polymers based on 3,4‐ethylenedioxythiophene and various benzodiazoles were synthesized by electrochemical polymerization. Spectroelectrochemical and kinetic studies of these polymers showed that all polymer films exhibited excellent electrochromic behavior, obvious optical contrast, and excellent stability. Among them, the response time of P3 film was the shortest (tc = 1.6 s, tb = 2.2 s), the coloring efficiency of P2 film was the highest (CE = 333 cm2·C−1), and the stability of P1 was the best (the ΔT loss of P1 after 1000 s cycles is only 2.3%). Therefore, these data prove that these new polymers have great potential in applications as electrochromic materials. [ABSTRACT FROM AUTHOR]

A simple and efficient route for the preparation of terphenyl derivatives via palladium-catalyzed sequential directed C-H arylation/Suzuki-Miyaura in 'one-pot' has been developed. 4,4′-(Cyclohexane-1,1-diyl)diphenol is an essential ligand. This reaction can tolerate a series of functional groups and provides the terphenyl derivatives in moderate to good yield. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A bis(β-diketone), 1,3-bis(4,4,4-trifluoro-1,3-dioxobutyl)phenyl (BTP), which contains a trifluorinated alkyl group, has been exploited to obtain three series of visible-light sensitive dinuclear rare-earth complexes with the general formula [Ln2(BTP)3L2] [Ln = Nd, L = DME ( 1), bpy ( 2), and phen ( 3); Ln = Yb, L = DME ( 4), bpy ( 5), and phen ( 6); Ln = Er, L = DME ( 7); DME = ethylene glycol dimethyl ether, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline]. An X-ray crystallographic analysis revealed that complexes 1, 2, 4, 5, and 7 are triple-stranded helical dinuclear structures that are formed by three bis(bidentate) ligands with two lanthanide ions. The room-temperature near-IR luminescent properties of complexes 1- 6 show that this bis(β-diketone) can effectively sensitize rare earths (Nd3+, Yb3+) and produce typical near-infrared luminescence upon excitation with visible light of the corresponding Nd3+ and Yb3+ ions. Additionally, two bidentate nitrogen ancillary ligands, 2,2-bipydine (bpy) and 1,10-phenanthroline (phen), have been applied to enhance the NIR luminescent properties. [ABSTRACT FROM AUTHOR]

Pd/C-catalyzed Suzuki-Miyaura cross-coupling between aryl bromides and arylboronic acids in 50% methanol aqueous solution proceeded smoothly in the presence of 18-crown-6. Various aryl bromides bearing electron-withdrawing groups and electron-donating groups coupled with arylboronic acid in high yields. In addition, the catalyst could be recycled five times without loss of activity. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The nuclear factor-κB (NF-κB) signaling pathway regulates cellular growth, survival, differentiation and development. In this study, the functions of IκB kinase (IKK)β in angiogenesis during mouse development were examined. Conditional disruption of the Ikkβ locus in endothelial cells using the well-characterized Tie2-Cre transgene resulted in embryonic lethality between embryonic day (E) 13.5 and E15.5. Examination of the mutant embryos revealed that while deletion of Ikkβ occurred in endothelial cells throughout the embryo, only the vascular network in the fetal liver was affected. Disruption of the fetal liver vasculature was accompanied by decreased cell proliferation and increased apoptosis of hepatocytes, but hematopoiesis was not affected. Increased apoptosis was not observed outside of fetal liver in the mutant embryos. These results indicate that the IKKβ/NF-κB pathway plays a previously unappreciated role in development of the sinusoidal vasculature in the fetal liver and additionally that this pathway is critical in the crosstalk between endothelial cells and hepatocytes during mouse development. Developmental Dynamics 237:2926-2935, 2008. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

A series of novel polymers (coded as BCT‐1 to BCT‐6 (BTC is block triphenylamine)) based on N1‐(4‐aminophenyl)‐N1‐phenyl benzene‐1,4‐diamine, pyridine‐2,6‐dicarboxylic acid, 4,4′‐(phenyl azanediyl)dibenzoic acid (PDA), and different diamine compounds were synthesized successfully through a polymer condensation reaction. For comparison, model polymers, BCT–2,6‐pyridine dicarboxylic acid (PA) and BCT–PDA, were synthesized as well. The electrochromic properties of the BCTs were determined via an electrochemical workstation and a UV–visible spectrophotometer. Through electrooxidation, the polymer films showed reversible redox processes and steady color changes. In a comparision of the electrochromic characteristics of the BCTs, almost all the novel polymer films showed a better electrochromism stability, a higher electrochromic coloration efficiency (CE), and a more rapid switching time than BCT–PA and BCT–PDA. Among these polymers, BCT‐1 exhibited the highest CE of 266.7 cm2/C, and BCT‐4 showed the most rapid switching time (color switching time = 3.08 s and bleaching time = 2.01 s). © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47264. [ABSTRACT FROM AUTHOR]