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Dithienobenzodithiophene (DTBDT)-based polymers exhibit good planarity, strong crystallinity, and high mobility. However, their application in organic solar cells (OSCs), especially in high-voltage systems, is very limited compared to that of benzodithiophene (BDT)-based analogs. Herein, we utilize a DTBDT-based polymer PE56 to pair with three wide-bandgap benzotriazole (BTA)-based nonfullerene acceptors (NFAs) and explore the potential for high-voltage OSCs. The chlorination on different positions of parent acceptor BTA5 produces BTA5-Cl and Cl-BTA5, where the Cl atoms are attached to the terminal benzyl ring and the bridge BTA unit, respectively. Due to the small energy offsets, PE56: BTA5, PE56: BTA5-Cl, and PE56: Cl-BTA5 achieved high open-circuit voltage (VOC) of 1.25, 1.20, and 1.17 V, respectively. The gradually decreased VOC values are attributed to the increased non-radiative recombination losses (0.17, 0.21, and 0.24 eV) caused by the chlorination and its position isomerization from terminals to BTA units. Chlorination could improve the miscibility between the donor and acceptor and thus form ordered molecular packing, facilitating photocurrent generation. The corresponding power conversion efficiency (PCE) increased from 5.44% to 9.71% and 11.18%. PE56: Cl-BTA5 achieved the highest PCE due to its efficient exciton dissociation, better charge transport, and suppressed charge recombination. Our results demonstrate that DTBDT-based polymer can be used in high-voltage OSCs, and the chlorination position of BTA-based NFAs greatly affects the photovoltaic performance. [ABSTRACT FROM AUTHOR]

An arc glow discharge device was used to prepare a helical carbon fiber skeleton with helical carbon fibers hooked to each other by spraying a hydrogen and ethanol mixture onto the iron wire substrate through the discharge area, using anhydrous ethanol as the carbon source. The samples were characterized by SEM, EDS, Raman and XPS. A growth mechanism of helical carbon fiber driven by C sp3 was proposed. The various growth modes of carbon fiber during the formation of carbon fiber skeleton were investigated. A ring appearance that indicated a change in the direction of carbon fiber growth was observed. And double helical carbon fiber was constructed from single helical carbon fiber in two ways. Super-large carbon fiber with a diameter of about 13 μm was observed, and it was speculated that this super-large carbon fiber is the backbone of the carbon fiber skeleton. The mechanical properties of the carbon fiber skeleton are isotropic. [ABSTRACT FROM AUTHOR]

High-voltage organic solar cells (OSCs) have received increasing attention because of their promising applications in tandem devices and indoor photovoltaics, but the trade-off between energy loss and charge generation induced by exciton binding energy (Eb) has become one of the biggest bottlenecks limiting the development of this field. Here, a wide bandgap (WBG) nonfullerene acceptor BTA503 with reduced Eb is designed by changing the phenyl side chain on the central core of Cl-BTA5 to an alkyl chain. The diverse π-π interactions and enhanced molecular stacking of BTA503 are responsible for its reduced Eb. Furthermore, both the diminished charge recombination and the fast exciton dissociation caused by the small Eb favor the generation of more charge carriers for the PTQ10:BTA503 combination. The efficient Forster resonance energy transfer (FRET) and multiple π-π stacking patterns provide additional charge transfer and transport pathways. Ultimately, the PTQ10:BTA503-based OSC device achieves a VOC of 1.112 V and a PCE of 12.70%, which is higher than that of PTQ10:Cl-BTA5 (PCE=10.92%). Simultaneously, the thick film (~300 nm) binary device of PTQ10:BTA503 achieves a PCE of 10.13% with a VOC of 1.102 V, which is the best result for thick film high-voltage OSCs. More importantly, the ternary device of PTQ10: BTA503:Cl-BTA5 (1:0.9:0.1) realizes a champion PCE of 13.12% with a VOC of 1.126 V. Our study demonstrates that it is an effective strategy to reduce Eb of A2-A1-D-A1-A2 type WBG acceptors by modulating the side chains on D unit, which further favors the corresponding devices to obtain world-record PCE and improves their potential for commercial applications. [ABSTRACT FROM AUTHOR]

During the ice flood period of the Yellow River, the fracture and destruction of river ice can easily lead to the formation of ice jams and ice dams in the curved and narrow reaches. However, the occurrence and development mechanism of river ice fracture remain incompletely understood in the Yellow River. Therefore, based on the three-point bending physical test of the Yellow River ice, a three-point bending fracture numerical model of the Yellow River ice was constructed. The fracture failure process of the Yellow River ice under three-point bending was simulated, and the effects of the crack-to-height ratio and ice grain size on the fracture properties of the river ice were analyzed. By comparing the results with those of physical tests on river ice, it is evident that the fracture model can effectively simulate the cracking process of river ice. Within the confines of the simulated sample size spectrum, as the crack-to-height ratio varies from 0.2 to 0.8, the fracture toughness value of the Yellow River ice spans a range from 115.01 to 143.37 KPa·m1/2. Correspondingly, within the simulated calculation values ranging from 5.38 mm to 24.07 mm for ice crystal size, the fracture toughness value of the Yellow River ice exhibits a range from 116.89 to 143.37 KPa·m1/2. The findings reveal that an increase in the crack-to-depth ratio leads to a decrement in the fracture toughness of river ice. Within the scale range encompassed by the model calculations, as the average size of the ice crystal grains augments, the fracture toughness of the river ice exhibits a gradual ascending trend. The research results provide a parameter basis for studying the fracture performance of the Yellow River ice using a numerical simulation method and lays a foundation for investigating the cracking process of river ice from macro and micro multi-scales. [ABSTRACT FROM AUTHOR]

In recent years, the organic solar cells (OSCs) research hotspot is the modification of end groups and alkyl side chains of A‐DA'D‐A‐type nonfullerene acceptors (NFAs). However, the development of novel NFAs by changing the different bridged atom substitution of the central core is lagging behind. Herein, two wide‐bandgap A2‐A1‐D‐A1‐A2‐type NFAs with different central cores, namely BTA501 and BTA502, are developed to improve the photovoltaic performance of high‐voltage OSCs. BTA501 adopted an indacenodithiophene (IDT) core, whereas BTA502 applied a silaindacenodithiophene (SiIDT) core. Expectedly, the SiIDT‐based BTA502 exhibits a higher lowest unoccupied molecular orbital level and wider bandgap than BTA501, which thus enhances the open‐circuit voltage (VOC) but slightly decreases the short‐circuit current density (JSC) of OSCs. Moreover, the stronger self‐aggregation characteristics and weaker π–π stacking of BTA502 severely affect the exciton dissociation and charge transport. When blended with two classic p‐type polymers J52‐F and PTB7‐Th, both combinations based on BTA502 exhibit inferior device performance compared with BTA501. Excitingly, the device of J52‐F: BTA501 achieves a VOC of 1.037 V with a power conversion efficiency of 11.82% and a JSC of 15.89 mA cm−2, which are among the highest values for high‐voltage OSCs with VOC above 1.0 V. [ABSTRACT FROM AUTHOR]

Despite the edible fungus Amillariella mellea possessing a variety of biological activities, its effects on diabetes are still unclear. Polysaccharides are the main bioactive ingredients. In order to destroy the cell wall to obtain more polysaccharides, we used NaOH solution to extract Amillariella mellea fruiting bodies. The alkali extraction (AAMP) was identified as a polysaccharide-enriched fraction. Using type 2 diabetic rats induced by co-treatment of a high fat diet (HFD) and dexamethasone (DEX), we evaluated the hypoglycemic effects of AAMP. The results showed that oral administration of a high dose of AAMP markedly lowered fasting blood glucose, improving glucose intolerance and insulin resistance. AAMP also enhanced the level of LPL and the expressions of two critical lipases ATGL and HSL, leading to a decrease of serum triglyceride. In addition, AAMP specifically suppressed the expression of SREBP-1c, resulting in AAMP observably inhibiting lipid accumulation in the liver. These findings demonstrated that the improvement of AAMP on HFD/DEX-induced insulin resistance was correlated with its regulation of lipid metabolism. Our results indicated that AAMP could be a novel natural drug or health food used for the treatment of diabetes. [ABSTRACT FROM AUTHOR]

Chinese fir is an extremely important economic tree species in southern China. In recent years, 74.5% of Chinese fir saplings suffered from shoot blight in Shunchang County, Nanping City, Fujian Province, China. Seventeen isolates were collected from rotten shoots, and their pathogenicity was confirmed following Koch's postulates. The five pathogenic isolates were identified as belonging to the genus Bipolaris based on morphological characteristics, including septate and geniculate conidiophores, smooth to slightly verruculose conidiogenous nodes, dematiaceous phragmospore conidia, oblong or fusiform conidia, and slightly protruding or truncate hilum on conidia, but the number of pseudosepta (3 to 11, mostly 5 to 8) and the size of conidia ([22.81 to 116.13] × [9.16 to 26.58] μm) are different from those of the known species of Bipolaris . A phylogenetic analysis based on ITS, GAPDH , and Tef1-α sequences determined that the five strains belong to a new species of Bipolaris , and the name Bipolaris fujianensis sp. nov. is proposed. The fungicide sensitivity of the pathogen strain Cfsb3 was further evaluated using eight fungicides. Flusilazole, difenoconazole, tebuconazole, and propiconazole exhibited high toxicity to Cfsb3, and the effective concentration inhibiting 50% (EC 50 ) of mycelial growth was 0.08, 0.20, 0.34, and 0.36 μg/ml, respectively, for these four fungicides. Flusilazole, difenoconazole, and iprodione inhibited B. fujianensis by 100% on detached Chinese fir shoots at their recommended concentrations, but azoxystrobin and thiram were ineffective. In conclusion, this study reported an emerging pathogen of Chinese fir sapling shoot blight and proposed triazole and dicarboximide fungicides for disease control., Competing Interests: The author(s) declare no conflict of interest.