The senescence of fruit is a complex physiological process, with various cell types within the pericarp, making it highly challenging to elucidate their individual roles in fruit senescence. In this ...study, a single-cell expression atlas of the pericarp of pitaya (Hylocereus undatus) is constructed, revealing exocarp and mesocarp cells undergoing the most significant changes during the fruit senescence process. Pseudotime analysis establishes cellular differentiation and gene expression trajectories during senescence. Early-stage oxidative stress imbalance is followed by the activation of resistance in exocarp cells, subsequently senescence-associated proteins accumulate in the mesocarp cells at late-stage senescence. The central role of the early response factor HuCMB1 is unveiled in the senescence regulatory network. This study provides a spatiotemporal perspective for a deeper understanding of the dynamic senescence process in plants.
It was demonstrated in our previous research that trypsin scavenges superoxide anions. In this study, the mechanisms of storage quality improvement by trypsin were evaluated in H. undatus.
Trypsin ...significantly delayed the weight loss and decreased the levels of ROS and membrane lipid peroxidation. Transcriptome profiles of H. undatus treated with trypsin revealed the pathways and regulatory mechanisms of ROS genes that were up- or downregulated following trypsin treatment by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses. The current results showed that through the regulation of the expression of hub redox enzymes, especially thioredoxin-related proteins, trypsin can maintain low levels of endogenous active oxygen species, reduce malondialdehyde content and delay fruit aging. In addition, the results of protein-protein interaction networks suggested that the downregulated NAD(P) H and lignin pathways might be the key regulatory mechanisms governed by trypsin.
Trypsin significantly prolonged the storage life of H. undatus through regulatory on the endogenous ROS metabolism. As a new biopreservative, trypsin is highly efficient, safe and economical. Therefore, trypsin possesses technical feasibility for the quality control of fruit storage.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Oxidation behaviors at 1300°C, room temperature flexural strength and fracture toughness of hot-pressing Nb–XW (X=10, 20, 30wt%) alloys were investigated by isothermal oxidation, three-point bending ...(TPB) and un-precracked single edge notch bending (SENB) tests. It is shown that the oxidation resistance of Nb–XW alloys was improved with the increasing of W content due to WO3 in oxidation scale reducing the oxygen-vacancy concentration and preventing Nb5+ from outward diffusing. However, 30% W was a limit concerning the effectiveness of W in improving oxidation resistance of Nb–W alloys. W addition to Nb gives rise to an increase in room temperature flexural strength due to solid solution strengthening, but W content must meet or even exceed 30% which can efficiently strengthen the alloy. Fracture toughness first increases obviously and then decreases slightly with W changing from 10% to 30%, which was attributed to ductile fracture propensity in 20W alloy and remarkable solid solution strengthening in 30W alloy, respectively. Considering the good balance of high temperature oxidation resistance, room temperature flexural strength and fracture toughness, W content of 30% was optimum for Nb–W alloys.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
It has been revealed by us that superoxide scavenging is a new activity of trypsin. In this study, the synergistic mechanisms of trypsin and superoxide dismutases (SODs) were evaluated in
(pitaya). ...Trypsin significantly improved the storage quality of
, including weight loss impediment and decrease of cellular injury. The regulatory mechanisms of 16 SOD genes by trypsin were revealed using transcriptomic analysis on
. Results revealed that important physiological metabolisms, such as antioxidant activities or metal ion transport were induced, and defense responses were inhibited by trypsin. Furthermore, the results of protein-protein interaction (PPI) networks showed that besides the entire ROS network, the tiny SODs sub-network was also a scale-free network. Cu/Zn SODs acted as the hub that SODs synergized with trypsin during the storage of
With the recent advance in chemical modification of fullerenes, electrosynthesis has demonstrated increasing importance in regioselective synthesis of novel fullerene derivatives. Herein, we report ...successively regioselective synthesis of stable tetra- and hexafunctionalized 60fullerene derivatives. The cycloaddition reaction of the electrochemically generated dianions from 60fulleroindolines with phthaloyl chloride regioselectively affords 1,2,4,17-functionalized 60fullerene derivatives with two attached ketone groups and a unique addition pattern, where the heterocycle is rearranged to a 5,6-junction and the carbocycle is fused to an adjacent 6,6-junction. This addition pattern is in sharp contrast with that of the previously reported biscycloadducts, where both cycles are appended to 6,6-junctions. The obtained tetrafunctionalized compounds can be successively manipulated to 1,2,3,4,9,10-functionalized 60fullerene derivatives with an intriguing "
"-shaped configuration
a novel electrochemical protonation. Importantly, the stability of tetrafunctionalized 60fullerene products allows them to be applied in planar perovskite solar cells as efficient electron transport layers.
Suitable electron transport materials bearing good interfacial contact, improved electron transport ability, and matched energy levels are indispensable for developing efficient perovskite solar ...cells (PSCs). Herein, regular (n‐i‐p) planar Cs0.05FA0.83MA0.12PbI2.55Br0.45 (CsFAMA) PSC devices were fabricated using a pyridine‐functionalized fullerene derivative (C60‐3‐BPy) as an independent electron transport layer (ETL), delivering a decent power conversion efficiency (PCE) of 18.22%, which is dramatically higher than that of the control device based on 6,6‐phenyl‐C61‐butyric acid methyl ester (PCBM) ETL (15.70%). The energy level offset between C60‐3‐BPy and the perovskite is smaller than that based on PCBM ETL, which is beneficial for efficient ohmic contact in ETL/perovskite interface and improved open‐circuit voltage (Voc). Moreover, C60‐3‐BPy affords strong coordination interactions with perovskite, leading to an improved film quality of the perovskite layer with enlarged grain size and decreased trap state density, which contribute to facilitated electron extraction as reflected by the increases of both the fill factor (FF) and the short‐circuit current (Jsc). C60‐3‐BPy‐facilitated electron extraction further results in hysteresis‐free devices.
Regular n‐i‐p CsFAMA perovskite solar cells using C60‐3‐BPy as an independent ETL afforded a decent PCE of 18.22% with negligible current‐voltage hysteresis, which outperformed the control device with PCBM ETL (15.70%) due to the improved film quality of perovskite layer, the matched energy alignment of the device through the modified work function of the ITO electrode and improved charge extraction.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We report the fabrication of polymer/inorganic hybrid solar cells （HSCs） based on CdSe nanorods （NRs） and the semiconducting polymer PTB7. The power conversion efficiency of HSCs can be significantly ...enhanced by engineering the polymer/nanocrystal interface with ethanedithiol （EDT） and 1,4-benzenedithiol （1,4-BDT） treatments and reached 2.58% and 2.79%, respectively. These results were preferable to that of a pyridine-coated NR-based device （1.75%）. This improvement was attributed to the thiol groups of EDT and 1,4-BDT, which can tightly coordinate the Cd ions to form Cd-thialate on CdSe NR surfaces, thereby effectively passivating the NR surface and reducing the active layer defects. Therefore, the rate of exciton generation and dissociation was enhanced and led to the improvement of the device performance.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Droplet atomization characteristics and its morphology in twin-wire arc sprayed (TWAS) Ni-Al were explored in depth. Both numerical model and theoretical method were built for calculating the process ...of the droplet deformation and breakup in air flow, which based on the standard k-ε model and the volume of fluid (VOF) dual-phase flow model. The atomization characteristics of double droplets and three droplets were also studied in the atomization process by simulation. The micro structure and the morphology of the composite coatings were analyzed by SEM and TEM. The experimental results indicate that TWAS droplets are the process of explosive breakup or two steps breakup. Morphology of the TWAS prepared Ni-20wt.%Al and Ni-5wt.%Al particles was accordingly characterized by SEM. The phase compositions of the Ni-Al particles were obtained by EDS. By testing the velocity of sprayed particles, the change rule of particles with spray pressure was obtained. Ni twins are discovered in the Ni-Al coating due to rapid cooling in TWAS process.
Organic–inorganic perovskite solar cells have recently emerged at the forefront of photovoltaics research. Here, for the first time, graphdiyne (GD), a novel two dimension carbon material, is doped ...into PCBM layer of perovskite solar cell with an inverted structure (ITO/PEDOT:PSS/CH3NH3PbI3–x Cl x /PCBM:GD/C60/Al) to improve the electron transport. The optimized PCE of 14.8% was achieved. Also, an average power conversion efficiency (PCE) of PCBM:GD-based devices was observed with 28.7% enhancement (13.9% vs 10.8%) compared to that of pure PCBM-based ones. According to scanning electron microscopy, conductive atomic force microscopy, space charge limited current, and photoluminescence quenching measurements, the enhanced current density and fill factor of PCBM:GD-based devices were ascribed to the better coverage on the perovskite layer, improved electrical conductivity, strong electron mobility, and efficient charge extraction. Small hysteresis and stable power output under working condition (14.4%) have also been demonstrated for PCBM:GD based devices. The enhanced device performances indicated the improvement of film conductivity and interfacial coverage based on GD doping which brought the high PCE of the devices and the data repeatability. In this work, GD demonstrates its great potential for applications in photovoltaic field owing to its networks with delocalized π-systems and unique conductivity advantage.
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IJS, KILJ, NUK, PNG, UL, UM
Incorporating n-type fullerene derivatives into the perovskite layer affording bulk heterojunction (BHJ) perovskite solar cells (PSCs) is an effective strategy to passivate trap states, consequently ...reducing the current–voltage hysteresis and improving the device performance. Herein, we report the synthesis of a novel pyridine-functionalized fullerene derivative (C60-PyP) via a 1,3-dipolar cycloaddition reaction, and the unambiguous determination of its molecular structure by X-ray single crystal diffraction. Upon incorporating C60-PyP as an additive with an optimized doping ratio of 0.13 wt% into the CH3NH3Pbl3 (MAPbI3) perovskite precursor, the regular-structure bulk heterojunction PSC devices exhibit a best power conversion efficiency (PCE) of 19.82%, which is dramatically enhanced relative to that of the control devices (17.61%). The C60-PyP additive provides heterogeneous nucleation sites, leading to the decrease of the nucleation Gibbs free energy and consequently enlarged grain size and improved crystallization of the MAPbI3 perovskite film. Besides, incorporation of C60-PyP results in enhanced crystalline orientation as confirmed by grazing-incidence X-ray diffraction (GIXRD) measurements. Meanwhile, the coordination interaction between the N atom of the pyridine moiety within C60-PyP and the Pb2+ ion within MAPbl3 leads to the passivation of the trap states of the perovskite layer, jointly contributing to the improved device performance and markedly suppressed current–voltage hysteresis. Moreover, the ambient stability of the devices is improved upon C60-PyP incorporation due to the hydrophobic nature of the C60-PyP molecule, which presumably resides at the grain boundaries.
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