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The side chains on non‐fullerene acceptors (NFAs) can affect greatly the photovoltaic performances of the resulting organic solar cells (OSCs) by regulating the molecular packing and orientation of NFAs. To explore suitable side groups for asymmetric simple NFAs, in this work, we design and synthesize two A‐D1‐A′‐D2‐A type NFAs, NTC‐4Cl, and PhNTC‐4Cl, which own flexible alkyloxy and rigid aryloxy side chains on the A′ cores, respectively. Due to the same molecular backbone (A′: benzotriazole; D1: thiophene; D2: cyclopentadithiophene; A: dichlorodicyanoindanone), NTC‐4Cl and PhNTC‐4Cl have similar absorptions and energy levels. However, the PhNTC‐4Cl‐based OSC gives a higher power conversion efficiency than that of the NTC‐4Cl‐based one (11.09% vs. 10.82%) because PhNTC‐4Cl shows more compact π–π stacking and dominant face‐on orientation, enhancing charge transport and mitigating charge recombination. Therefore, this work provides a new insight into the molecular design of high‐performance NFAs, especially the rational choice of side groups on asymmetric simple NFAs. [ABSTRACT FROM AUTHOR]

To date, the fused‐ring electron acceptors show the best photovoltaic performances, and the development of simple non‐fullerene acceptors via intramolecular noncovalent interactions can reduce synthetic costs. In this work, four simple non‐fullerene acceptors with an A‐D‐A'‐D‐A configuration (QCIC1, QCIC2, QCIC3, and QCIC4) were synthesized. They contained the same conjugated backbone (A': quinoxaline; D: cyclopentadithiophene; A: dicyano‐indanone) but different halogen atoms and alkyl side chains. Due to the chlorination on the end‐groups and the most and/or longest branched alkyl side chains on the backbone, the blended film composed of QCIC3 and donor poly{[2,6′‐4,8‐di(5‐ethylhexylthienyl)benzo [1,2‐b : 4,5‐b′]dithiophene]‐alt‐[5,5‐(1′,3′‐di‐2‐thienyl‐5′,7′‐bis(2‐ethylhexyl)benzo[1′,2′‐c : 4′,5′‐c′]dithiophene‐4,8‐dione)]} (PBDB‐T) exhibited the strongest π‐π stacking and the most suitable phase‐separation domains among the four blended films. Therefore, the QCIC3‐based organic solar cells yielded the highest power conversion efficiency of 10.55 %. This work provides a pathway to optimize the molecular arrangements and enhance the photovoltaic property of simple electron acceptors through subtle chemical modifications. [ABSTRACT FROM AUTHOR]

The enhancement of turbulence was considered to be able to bring about better mixing and more uniform distribution of concentration generally, but its influence on ultrafast competitive reactions is an open question. Cu‐Zn co‐precipitation was carried out in three types of micro‐reactors and the turbulent intensity was regulated by changing flow rate and ultrasound power, respectively. Energy‐dispersive spectrometer of precipitates and characteristic aging time indicate the best uniformity of Cu‐Zn distribution in precipitates appears at moderate turbulent intensity. The numerical simulation shows the uniformities of precipitation both in time and in space are impacted by mixing simultaneously but with opposite direction, resulting in the appearance of maximum. The unevenness of Cu‐Zn distribution caused by inconsistent reaction rates along the time will be erased during subsequent structural evolution, while that caused by diverse reaction rates at various positions can survive and further affect the structure and performance of catalysts. [ABSTRACT FROM AUTHOR]

The hot compression experiments are accomplished to investigate the microstructural evolution of as‐cast H13 steel during homogenization treatment and hot deformation. At a certain homogenization temperature, the dynamic recrystallization (DRX) volume fraction increases with increasing strain and deformation temperature and decreasing strain rate. However, the DRX is also easy to proceed at a high strain rate of 5 s−1 due to the high shear stress. The recrystallization is inhibited in a dendrite segregation region. The residual dendrite segregation left after homogenization treatment will improve the recrystallization nucleation rate during the subsequent deformation. The recrystallization grains preferentially nucleate in the dendrite region, and the grain growth is inhibited by the dendrite segregation. The partial homogenization before deformation is beneficial to achieve the fine microstructure. [ABSTRACT FROM AUTHOR]

Objective: Nucleotide binding domain and leucine‐rich repeat pyrin 3 domain (NLRP3) inflammasome is known for activating pro‐inflammatory cytokines in knee osteoarthritis (OA). This study was performed to identify whether NLRP3 inflammasome can be triggered by lipopolysaccharides (LPS) and adenosine triphos adenine (ATP), which are positively related with knee OA severity in joint‐spaces, in human fibroblast‐like synoviocytes (FLS), and to identify whether estrogen would inhibit the activation of NLRP3 inflammasome. Methods: In the present study, human FLS were isolated from the knee OA in patients during arthroplasty, and were treated with LPS and ATP in the presence or absence of estradiol (E2). The messenger RNA (mRNA) and protein levels of NLRP3 components were analyzed by real‐time polymerase chain reaction and western blotting, respectively. Enzyme‐linked immunosorbent assay (ELISA) was used to examine interleukin (IL)‐1β and IL‐18 content in the supernatant. Estrogen receptor α inhibitor MPP and β inhibitor PHTPP were used to explore how E2 works. Results: Our results demonstrated that treatment with LPS and ATP increased significantly both in mRNA and protein levels of all the NLRP3 inflammasome components, and triggered the NLRP3 inflammasome, followed by upregulated IL‐1β and IL‐18 in the cell supernatant. E2 appeared to inhibit the activation of NLRP3 inflammasome by diminishing mRNA and protein levels of NLRP3 through estrogen receptor β, and decreased the expression of IL‐1β and IL‐18 as well. Conclusion: These results suggested the increased LPS and ATP in joint‐space may promote knee OA by NLRP3 inflammasome and E2 may exert a protective effect by inhibiting the activation of NLRP3 inflammasome in FLS. [ABSTRACT FROM AUTHOR]