Herein, we report a deep‐red TADF emitter pCNQ–TPA, composed of quinoxaline‐5,8‐dicarbonitrile (pCNQ) acceptor and triphenylamine (TPA) donor. pCNQ–TPA supported its OLED with desired CIE coordinates ...of (0.69, 0.31) and the record maximum external quantum efficiency of 30.3 %, which is the best red TADF diode with Rec.2020 gamut for UHDTV. It is showed that through tuning pCNQ–TPA doping concentration, intra‐ and inter‐molecular charge transfer are balanced to synchronously improve emission color saturation and TADF radiation, and remedy aggregation‐induced quenching, rendering photoluminescence quantum yield (PLQY) reaching 90 % for deep‐red emission peaked at ≈690 nm. Quasi‐planar structure further endows pCNQ–TPA with an improved horizontal ratio of emitting dipole orientation, which increases light out‐coupling ratio to 0.34 for achieving the state‐of‐the‐art device efficiencies.
A deep‐red TADF emitter pCNQ–TPA for UHD display was demonstrated, which realized the desired chromaticity matching rec.2020 standard and the record external quantum efficiency beyond 30 %. It is showed that its quasi‐planar structure not only improves horizontal ratio of emitting dipole orientation for out‐coupling enhancement, but also balances the intra‐ and inter‐molecular charge transfer for radiation facilitation and quenching suppression.
In this communication, the preparation of crosslinked polydicyclopentadiene (PDCPD) nanoparticles via ring‐opening metathesis polymerization (ROMP)‐induced self‐assembly approach is reported. For the ...ROMPs, the macromolecular chain transfer agents (Macro‐CTAs) are synthesized via the ring‐opening polymerization (ROP) of ε‐caprolactone (CL) with cis‐2‐butene‐1,4‐diol as the initiator. The ROMPs are performed with chloroform, tetrahydrofuran, toluene, 1,4‐dioxane, and N,N‐dimethylacetamide as the solvents, respectively, which are catalyzed with Grubbs second generation catalyst. It is found that the crosslinked PDCPD nanoparticles are obtained with spherical, cylindrical to planar morphologies, depending on the molecular weights of Macro‐CTAs, the concentrations of DCPD and the natures of solvents. The polymerization induced self‐assembly (ROMPISA) by the use of a non‐norbornene‐based macromolecular chain transfer agent provides a new and efficient approach to prepare crosslinked polymer nanoparticles.
In this communication, the preparation of crosslinked polydicyclopentadiene (PDCPD) nanoparticles via ring‐opening metathesis polymerization (ROMP)‐induced self‐assembly approach is reported.
This work addresses the susceptibility to stress corrosion cracking in 3.5% NaCl solution (simulating seawater) of three differently obtained microstructures of a nickel-aluminum bronze alloy using ...slow strain rate tensile tests. The results showed that the stress corrosion cracking susceptibility of annealed and normalized alloys increased with the decrease of the strain rate as the metal became more severely corroded and dissolved at the crack tips. The continuous or semi-continuous α + κⅢ eutectoid structure is sensitive to stress corrosion cracking, resulting in the highest susceptibility of annealed alloy. The thin and overlapped Widmanstatten α grain hinders extension of the cracks and thus decreases the stress corrosion cracking susceptibility of normalized alloy to some degree. The quenched/aged alloy with homogeneous microstructure without α + κⅢ eutectoid structure and the β’ phase exhibits the lowest susceptibility. The stress corrosion cracking process of nickel-aluminum bronze alloys was revealed and is properly explained by the oxide film rupture and anodic dissolution mechanism as well as the hydrogen induced cracking mechanism.
The existence of aftershocks in an earthquake sequence can impact the analysis of the mainshock. In this study, we present a method for deleting an aftershock sequence based on the spatial ...relationship between earthquakes and faults. This method improves the performance of space window selection in the classical K-K method by eliminating aftershocks with an ideal fault buffer zone. The determination of fault buffer zones is based on a trial-and-error analysis of 69,714 earthquake records from the China Seismic Network Center (CENC) collected between 1980 and 2020. We selected 20 typical big earthquakes (ML7.0–8.0 or ~Ms6.6–8.0; for earthquakes above magnitude Ms7 or ML7.2, ML is approximately equal to Ms) as the mainshocks to establish the fault buffer zones. We also propose an empirical formula to determine the distance of the fault buffer zone by counting the aftershock deletion effect at different buffer distances. Compared with the classical K-K method, our method considers the correlation between the spatial distribution of aftershocks and faults, eliminates earthquake groups that are not related to the mainshock, greatly reduces the spatial range of aftershocks, improves the performance of deleting aftershocks of different magnitudes, and provides a new rule and reference for aftershock deletion.
Previous intervention studies have shown some benefits of dark chocolate for the cardiovascular system, but it has not been established whether dark chocolate intake is associated with the risk of ...cardiovascular diseases (CVDs). To investigate the causality between dark chocolate intake and the risk of CVDs, a Mendelian randomization (MR) study was conducted. We obtained summary-level data on dark chocolate intake and CVDs from publicly available genome-wide association studies. In this MR study, the main approach was to use a fixed-effect model with inverse variance weighted (IVW) and evaluate the robustness of the results via sensitivity analysis. We found that dark chocolate intake was significantly associated with the reduction of the risk of essential hypertension (EH) (OR = 0.73; 95% CI 0.60-0.88; p = 1.06 × 10
), as well as with the suggestive association to the reduced risk of venous thromboembolism (OR = 0.69; 95% CI 0.50-0.96; p = 2.81 × 10
). However, no association was found between dark chocolate intake and the other ten CVDs. Our study provides evidence for a causality between dark chocolate intake and a reduced risk of EH, which has important implications for the prevention of EH in the population.
Squamous promoter binding protein-like (SPL) proteins are a class of transcription factors that play essential roles in plant growth and development, signal transduction, and responses to biotic and ...abiotic stresses. The rapid development of whole genome sequencing has enabled the identification and characterization of SPL gene families in many plant species, but to date this has not been performed in quinoa (Chenopodium quinoa).
This study identified 23 SPL genes in quinoa, which were unevenly distributed on 18 quinoa chromosomes. Quinoa SPL genes were then classified into eight subfamilies based on homology to Arabidopsis thaliana SPL genes. We selected three dicotyledonous and monocotyledonous representative species, each associated with C. quinoa, for comparative sympatric mapping to better understand the evolution of the developmental mechanisms of the CqSPL family. Furthermore, we also used 15 representative genes from eight subfamilies to characterize CqSPLs gene expression in different tissues and at different fruit developmental stages under six different abiotic stress conditions.
This study, the first to identify and characterize SPL genes in quinoa, reported that CqSPL genes, especially CqSPL1, play a critical role in quinoa development and in its response to various abiotic stresses.
Autoimmune regulator (AIRE), whose gene mutation is considered to be a causative factor of autoimmune polyglandular syndrome type 1 (APS1), is an important transcriptional regulator. Studies on the ...role of AIRE in the central immune system have demonstrated that AIRE can eliminate autoreactive T cells by regulating the expression of a series of tissue specific antigens promiscuously in medullary thymic epithelial cells (mTECs) and induce regulatory T cell (Treg) production to maintain central immune tolerance. However, the related research of AIRE in peripheral tolerance is few. In order to understand the current research progress on AIRE in peripheral tolerance, this review mainly focuses on the expression and distribution of AIRE in peripheral tissues and organs, and the role of AIRE in peripheral immune tolerance such as regulating Toll-like receptor (TLR) expression and the maturation status of antigen presenting cells (APCs), inducing T cell tolerance and differentiation. This review will show us that AIRE also plays an indispensable role in the periphery.
The
b
-value is closely related to the crustal stress. By studying the
b
-value trends of regions before large earthquakes, we can obtain the evolution of crustal stress, which is generally ...considered useful earthquake precursor information. A quake is closely related to fault tectonic movement. In the past, the traditional
b
-value calculation method did not consider the spatial distribution of the fault. Here, we propose a new algorithm based on the fault’s buffer area, combining the spatial distribution and trend of the fault. This algorithm can accurately calculate the
b
-value changes for a specific fault using the fault as the basic independent unit. This method provides a useful reference for earthquake hazard judgment. Based on this algorithm, we use a total of 428,963 earthquakes from 1980 to 2013 after removal of the aftershock sequences and combine these quakes with the active fault distribution data to study the
b
-value changes before major earthquakes in western Sichuan. The results show that the
b
-values of the Fubianhe fault, Longmenshan main fault, and Shuangshi–Pengguan fault in western Sichuan decreased for at least 2 years before the earthquakes. The Longmenshan main fault area began to decrease slowly 5 years before the Wenchuan Ms8.0 earthquake and sharply decreased in the year before the quake, which reflects a significant change in crustal stress during this time. This conclusion and the method are available for long-term earthquake hazard assessment as a reference.
In this contribution, we reported the preparation of vitrimers by using commodity thermoplastics
via
post crosslinking with hindered urea bonds (HUBs). First, three hindered urea diisocyanates ...(HUDIs) were synthesized
via
the reactions of
N,N
’-di-tert-butylethylenediamine,
N,N
’-diethylethylenediamine, and piperazine with isophorone diisocyanate (IPDI). Thereafter, these HUDIs were used as the crosslinking agents to crosslink poly(hydroxyether of bisphenol A) (PH), a commodity thermoplastics. Fourier transform infrared (FTIR) spectroscopy and dynamic mechanical thermal analyses (DMTA) indicated that the PH thermosets were successfully obtained. It was found that the thermosets displayed the behavior of vitrimers. The PH thermosets can be reprocessed at elevated temperature without using catalyst and the mechanical strengths of vitrimers were recovered as high as 95%. The reprocessing properties are attributable to dynamic exchange reaction of hindered urea bonds, contingent on types of hindered urea bonds.
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