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To investigate the characteristics of destabilization damage in coal-rock complexes. Mechanical property tests were conducted on coal, rock, and their complexes. An infrared thermal camera was employed to real-time monitor the infrared (IR) radiation response signals during the destabilization damage process. A numerical model of coal-rock destabilization damage was developed, and its validity was verified. Deformed stress fields and displacement contours were obtained during the destabilization damage process. Upon destabilization, numerous cracks form at the base of the "coal" section, extending towards the interface, resulting in the formation of a wave-like deformation region. The differentiation in infrared thermal images is more pronounced in the "coal" section compared to the "rock" section. A high-stress region is evident at the interface, resulting in an area of high stress differentials. However, the bottom of the "coal" section also exhibits a region with high stress differentials and a more pronounced tendency towards destabilization damage. Displacement contours revealed that numerous units at the bottom of the "coal" section had slipped and misaligned, leading to the accumulation of damage and an elevation in the local damage level. It is a crucial factor contributing to the notable phenomenon of IR thermal image differentiation.
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Seismic anti-seismic rebar, as materials for supporting structures in large buildings, need to have excellent mechanical properties. By increasing the Nb content and controlling the cooling rate, the microstructure and precipitation behavior of the steel are adjusted to develop seismic anti-seismic rebar with excellent mechanical properties. Scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and a universal tensile testing machine were used to characterize the microstructure, precipitation phases, and mechanical properties of the experimental steels. The results show that the ferrite grain size, pearlite lamellae layer (ILS), and small-angle grain boundaries (LAGB) content of the high-Nb steels decreased to 6.39 µm, 0.12 µm, and 48.7%, respectively, as the Nb content was increased from 0.017 to 0.023 wt.% and the cooling rate was increased from 1 to 3 °C·s-1. The strength of the {332}<113>α texture is the highest in the high-Nb steels. The precipitated phase is (Nb, Ti, V)C with a diameter of ~50 nm, distributed on ferrite, and the matrix/precipitated phase mismatch is 8.16%, forming a semicommon-lattice interface between the two. The carbon diffusion coefficient model shows that increasing the Nb content can inhibit the diffusion of carbon atoms and reduce the ILS. The yield strength of the high-Nb steel is 556 MPa, and the tensile strength is 764 MPa.
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Conjugated polymers composed of alternating electron donor and acceptor segments have come to dominate the materials being considered for organic photoelectrodes and solar cells, in large part because of their favorable near-infrared absorption. The prototypical electron-transporting push-pull polymer poly(NDI2OD-T2) (N2200) is one such material. While reasonably efficient organic solar cells can be fabricated with N2200 as the acceptor, it generally fails to contribute as much photocurrent from its absorption bands as the donor with which it is paired. Moreover, transient absorption studies have shown N2200 to have a consistently short excited-state lifetime (â¼100 ps) that is dominated by a ground-state recovery. In this paper, we investigate whether these characteristics are intrinsic to the backbone structure of this polymer or if these are extrinsic effects from ubiquitous solution-phase and thin-film aggregates. We compare the solution-phase photophysics of N2200 with those of a pair of model compounds composed of alternating bithiophene (T2) donor and naphthalene diimide (NDI) acceptor units, NDI-T2-NDI and T2-NDI-T2, in a dilute solution. We find that the model compounds have even faster ground-state recovery dynamics (τ = 45, 27 ps) than the polymer (τ = 133 ps), despite remaining molecularly isolated in solution. In these molecules, as in the case of the N2200 polymer, the lowest excited state has a T2 to NDI charge-transfer (CT) character. Electronic-structure calculations indicate that the short lifetime of this state is due to fast nonradiative decay to the ground state (GS) promoted by strong CT-GS electronic coupling and strong electron-vibrational coupling with high-frequency (quantum) normal modes.
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High-carbon hardline steels are primarily used for the manufacture of tire beads for both automobiles and aircraft, and vanadium (V) microalloying is an important means of adjusting the microstructure of high-carbon hardline steels. Using scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM), the microstructure and precipitation phases of continuous cooled high-carbon steels were characterized, and the vanadium content, carbon diffusion coefficient, and critical precipitation temperature were calculated. The results showed that as the V content increased to 0.06 wt.%, the interlamellar spacing (ILS) of the pearlite in the experimental steel decreased to 0.110 µm, and the carbon diffusion coefficient in the experimental steel decreased to 0.98 × 10-3 cm2·s-1. The pearlite content in the experimental steel with 0.02 wt.% V reached its maximum at a cooling rate of 5 °C·s-1, and a small amount of bainite was observed in the experimental steel at a cooling rate of 10 °C·s-1. The precipitated phase was VC with a diameter of ~24.73 nm, and the misfit between ferrite and VC was 5.02%, forming a semi-coherent interface between the two. Atoms gradually adjust their positions to allow the growth of VC along the ferrite direction. As the V content increased to 0.06 wt.%, the precipitation-temperature-time curve (PTT) shifted to the left, and the critical nucleation temperature for homogeneous nucleation, grain boundary nucleation, and dislocation line nucleation increased from 570.6, 676.9, and 692.4 °C to 634.6, 748.5, and 755.5 °C, respectively.
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Colletotrichum tabacum, causing anthracnose in tobacco, is a notorious plant pathogen threatening tobacco production globally. The underlying mechanisms of C. tabacum effectors that interfere with plant defense are not well known. Here, we identified a novel effector, Cte1, from C. tabacum, and its expression was upregulated in the biotrophic stage. We found that Cte1 depresses plant cell death initiated by BAX and inhibits reactive oxygen species (ROS) bursts triggered by flg22 and chitin in Nicotiana benthamiana. The CTE1 knockout mutants decrease the virulence of C. tabacum to N. benthamiana, and the Cte1 transgenic N. benthamiana increase susceptibility to C. tabacum, verifying that Cte1 is involved in the pathogenicity of C. tabacum. We demonstrated that Cte1 interacted with NbCPR1, a Constitutive expresser of Plant Resistance (CPR) protein in plants. Silencing of NbCPR1 expression attenuated the infection of C. tabacum, indicating that NbCPR1 negatively regulates plant immune responses. Cte1 stabilizes NbCPR1 in N. benthamiana. Our study shows that Cte1 suppresses plant immunity to facilitate C. tabacum infection by intervening in the native function of NbCPR1. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2024.
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Colletotrichum , Proteínas Fúngicas , Nicotiana , Doenças das Plantas , Imunidade Vegetal , Proteínas de Plantas , Espécies Reativas de Oxigênio , Colletotrichum/patogenicidade , Nicotiana/microbiologia , Nicotiana/imunologia , Nicotiana/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Virulência , Regulação da Expressão Gênica de PlantasRESUMO
Understanding the composition of the bacterial community on the epidermis of wine grapes and in winery environments, as well as the response of grape epidermal bacteria to climatic factors, plays a significant role in ensuring grape health and promoting grape conversion into wine. This study utilized high-throughput sequencing to explore the composition of the bacterial community on the wine grape epidermis and representative wineries of three sub-regions of the Eastern Foothills of Helan Mountain, Ningxia. The results showed that the bacterial diversity and richness in the Yongning (YN) sub-region were the highest, with Qingtongxia (QTX) having the lowest levels of grape epidermal bacteria. The bacterial diversity and richness were the highest in Yinchuan (YC) and the lowest in YN in the winery environment (p < 0.05). The composition of dominant bacteria on the grape epidermis and in winery environments of the three sub-regions was not different at the phylum and genus level, but the levels of these dominant bacteria were different among the sub-regions. There was a correlation between grape epidermal bacteria and climatic factors. Approximately 93% of the bacterial genera on the grape epidermal genera in the three sub-regions are present in the winery environment and contain all the dominant bacterial genera on the epidermis.
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In this work, a dual-model immunoassay for detecting Aflatoxin B1 (AFB1) was developed based on 2,3-diaminophenazine (DAP) and carbon dots (CDs). Under the catalysis of horseradish peroxidase (HRP), the o-phthalylenediamine (OPD) was oxidized to DAP which had a yellow color and intense fluorescence. The color changes form colorless to yellow was used to design absorbance model immunoassay. Meanwhile, the absorption spectrum of DAP overlapped with the emission spectrum of CDs which caused the fluorescence of CDs to be quenched. The fluorescence changes of DAP and CDs were used to develop ratiometric fluorescence immunoassay. The dual-model immunoassay showed excellent sensitivity with the limits of detection (LODs) of 0.013 ng/mL for fluorescence mode and 0.062 ng/mL for absorbance mode. Meanwhile, both models exhibited great selectivity for AFB1. Additionally, the recovery rates suggested the proposed dual-model immunoassay had great potential in actual samples detection.
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Aflatoxina B1 , Pontos Quânticos , Aflatoxina B1/análise , Carbono , Imunoensaio , Limite de DetecçãoRESUMO
Ochratoxin A (OTA), a dangerous mycotoxin, is found in many crops. It is essential to create sensitive OTA detection techniques to ensure food safety. Based on the principle of p-nitrophenol (PNP) quenched the fluorescence of bovine serum albumin silver nanocluster (BSA-AgNCs) through an internal filtering effect, and phosphate activated fluorescence of calcein-Ce3+ system, a ratiometric fluorescence immunoassay for OTA detection was developed. In this strategy, the value of F518/F640 was used as a signal for response of OTA concentration. The detection range of this strategy was 0.625-25 ng/mL, the limit of detection (LOD) was 0.04 ng/mL. This new immunoassay offered a brand-new platform for detecting OTA.
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Técnicas Biossensoriais , Ocratoxinas , Prata , Ocratoxinas/análise , Imunoensaio/métodos , Limite de Detecção , Técnicas Biossensoriais/métodosRESUMO
We demonstrate a widely tunable single-frequency Er-doped ZBLAN fiber laser operating on a 4F9/2â4I9/2 transition band. An uncoated germanium (Ge) plate serves as a narrow-bandwidth etalon and is inserted in the cavity to achieve a single longitudinal mode selection. Wavelength tuning from 3373.8â nm to 3718.5â nm was demonstrated by using a blazed diffraction grating at 3.5â µm. At the emission peak of 3465.6â nm, the laser yields over 100â mW single-frequency output power, with a 3â dB linewidth <6.9â MHz, and a slope efficiency (with respect to the incident 1990â nm pump power) of 20.3%. Such a tunable mid-infrared single-frequency fiber laser may serve as a versatile laser source in spectroscopy and sensing applications.
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With theoretically endowing with high energy densities and environmentally friendly carbon neutralization ability, flexible fiber-shaped Li-CO2 battery emerges as a multipurpose platform for next-generation wearable electronics. Nevertheless, the ineluctable issues faced by cathode catalysts and Li anodes have brought enormous obstacles to the development of flexible fiber-shaped Li-CO2 batteries. Herein, a flexible fiber-shaped Li-CO2 battery based on Mo3 N2 cathode coating with atomic layer deposited TiN and Li3 N protected Li anode is constructed. Owing to the regulation surface electrons of Mo3 N2 by TiN, heterostructured cathode has more delocalized electrons which enable cathodes to stabilize 2-electron intermediate products Li2 C2 O4 by electron bridge bonds and avoid disproportionation into Li2 CO3 . Li3 N layers not only accelerate Li+ transportation but also avoid contact between Li and CO2 to form Li2 CO3 . Thus, the constructed Li-CO2 battery demonstrates a low charge potential of 3.22 V, low overpotential of 0.56 V, outstanding rate capabilities up to 1 A g-1 , and excellent long-term cycling (≈2000 h) with an energy efficiency of ≈80%. The fabricated flexible fiber-shaped Li-CO2 battery shows an ultrahigh energy density of 14 772.5 Wh kg-1 based on cathodes (340.8 Wh kg-1 based on device mass), and outstanding deformations adaptability, giving it great potential for wearable electronics.
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Hanseniaspora uvarum is a prevalent yeast species in vineyards. However, its application in grape wine fermentation remains limited. This study used culture-dependent and -independent approaches to investigate the dynamics of H. uvarum during the spontaneous fermentation of Cabernet Sauvignon grapes. The results revealed that H. uvarum constituted 77.49 % of the non-Saccharomyces yeast population during fermentation. An indigenous strain, QTX-C10, was isolated from the 148 H. uvarum strains using a multistep screening strategy. The 1:1 co-inoculation of QTX-C10 with Saccharomyces cerevisiae proved to be an optimal strategy for mixed fermentation, resulting in a 48.54 %-59.55 % increase in ethyl esters in Cabernet Sauvignon wine and a 96.94 %-110.92 % increase in Chardonnay wine. Furthermore, this approach reduced the acetic acid levels by 12.50 %-17.07 % for Cabernet Sauvignon wine and 10.81 %-17.78 % for Chardonnay wine. Additionally, increased ethyl ester content may enhance the tropical fruit flavor of Cabernet Sauvignon wines.
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Emerging quantum technologies hold the promise of unravelling difficult problems ranging from condensed matter to high-energy physics while, at the same time, motivating the search for unprecedented phenomena in their setting. Here, we use a custom-built superconducting qubit ladder to realize non-thermalizing states with rich entanglement structures in the middle of the energy spectrum. Despite effectively forming an "infinite" temperature ensemble, these states robustly encode quantum information far from equilibrium, as we demonstrate by measuring the fidelity and entanglement entropy in the quench dynamics of the ladder. Our approach harnesses the recently proposed type of non-ergodic behavior known as "rainbow scar," which allows us to obtain analytically exact eigenfunctions whose ergodicity-breaking properties can be conveniently controlled by randomizing the couplings of the model without affecting their energy. The on-demand tunability of quantum correlations via disorder allows for in situ control over ergodicity breaking, and it provides a knob for designing exotic many-body states that defy thermalization.
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976 nm + 1976 nm dual-wavelength pumped Er-doped ZBLAN fiber lasers are generally accepted as the preferred solution for achieving 3.5 µm lasing. However, the 2 µm band excited state absorption from the upper lasing level (4F9/2 â 4F7/2) depletes the Er ions population inversion, reducing the pump quantum efficiency and limiting the power scaling. In this work, we demonstrate that the pump quantum efficiency can be effectively improved by using a long-wavelength pump with lower excited state absorption rate. A 3.5 µm Er-doped ZBLAN fiber laser was built and its performances at different pump wavelengths were experimentally investigated in detail. A maximum output power at 3.46 µm of ~ 7.2 W with slope efficiency (with respect to absorbed 1990 nm pump power) of 41.2% was obtained with an optimized pump wavelength of 1990 nm, and the pump quantum efficiency was increased to 0.957 compared with the 0.819 for the conventional 1976 nm pumping scheme. Further power scaling was only limited by the available 1990 nm pump power. A numerical simulation was implemented to evaluate the cross section of excited state absorption via a theoretical fitting of experimental results. The potential of further power scaling was also discussed, based on the developed model.
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Squeezed light near an atomic resonance is beneficial for efficient atom-light quantum interfaces. It is desirable but challenging to directly generate in atoms due to excess noise from spontaneous emission and reabsorption. Here, we report on the use of energy-level modulation to actively control atomic coherence and interference in degenerate four-wave mixing (DFWM) and then to enhance the DFWM gain process for the generation of near-resonant squeezed twin beams. With this technique, we obtain a -2.6â dB intensity-difference squeezing detuned 100â MHz from the D1 F = 4 to F' = 4 transition of 133Cs.
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We report on the use of molecular acceptors (MAs) and donor polymers processed with a biomass-derived solvent (2-methyltetrahydrofuran, 2-MeTHF) to facilitate bulk heterojunction (BHJ) organic photovoltaics (OPVs) with power conversion efficiency (PCE) approaching 15%. Our approach makes use of two newly designed donor polymers with an opened ring unit in their structures along with three molecular acceptors (MAs) where the backbone and sidechain were engineered to enhance the processability of BHJ OPVs using 2-MeTHF, as evaluated by an analysis of donor-acceptor (D-A) miscibility and interaction parameters. To understand the differences in the PCE values that ranged from 9-15% as a function of composition, the surface, bulk, and interfacial BHJ morphologies were characterized at different length scales using atomic force microscopy, grazing-incidence wide-angle X-ray scattering, resonant soft X-ray scattering, X-ray photoelectron spectroscopy, and 2D solid-state nuclear magnetic resonance spectroscopy. Our results indicate that the favorable D-A intermixing that occurs in the best performing BHJ film with an average domain size of â¼25 nm, high domain purity, uniform distribution and enhanced local packing interactions - facilitates charge generation and extraction while limiting the trap-assisted recombination process in the device, leading to high effective mobility and good performance.
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In the domain of proton exchange membrane fuel cells (PEMFCs), the development of efficient and durable catalysts for the electro-oxidation of small organic molecules, especially of alcohols (methanol, ethanol, ethylene glycol, etâ al.) has always been a hot topic. A large number of related electrocatalysts with splendid performance have been designed and synthesized till now, while the preparation processes of most of them are demanding on experimental operations and conditions. Herein, we put forward a facile and handy method for the preparation of multifunctional Ni(OH)2 -supported core-shell Ni@Pd nanocomposites (Ni(OH)2 /Ni@Pd NCs) with the assistance of galvanic replacement reaction (GRR) at room temperature and ambient pressure. As expected, the Ni(OH)2 substrate can prevent the aggregation of core-shell (CS) Ni@Pd nanoparticles (NPs) and inhibit the formation of COads and further prevent Pd from being poisoned. The synergistic effect between CS Ni@Pd NPs and Ni(OH)2 substrate and the electronic effect between Pd shell and Ni core contribute to the outstanding electrocatalytic performance for methanol, ethanol, and ethylene glycol oxidation in alkaline condition. This study provides a succinct method for the design and preparation of efficient Pd-based electrocatalysts for alcohol electro-oxidation.
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The color and texture characteristics of crops can reflect their nitrogen (N) nutrient status and help optimize N fertilizer management. This study conducted a one-year field experiment to collect sugarcane leaf images at tillering and elongation stages using a commercial digital camera and extract leaf image color feature (CF) and texture feature (TF) parameters using digital image processing techniques. By analyzing the correlation between leaf N content and feature parameters, feature dimensionality reduction was performed using principal component analysis (PCA), and three regression methods (multiple linear regression; MLR, random forest regression; RF, stacking fusion model; SFM) were used to construct N content estimation models based on different image feature parameters. All models were built using five-fold cross-validation and grid search to verify the model performance and stability. The results showed that the models based on color-texture integrated principal component features (C-T-PCA) outperformed the single-feature models based on CF or TF. Among them, SFM had the highest accuracy for the validation dataset with the model coefficient of determination (R2) of 0.9264 for the tillering stage and 0.9111 for the elongation stage, with the maximum improvement of 9.85% and 8.91%, respectively, compared with the other tested models. In conclusion, the SFM framework based on C-T-PCA combines the advantages of multiple models to enhance the model performance while enhancing the anti-interference and generalization capabilities. Combining digital image processing techniques and machine learning facilitates fast and nondestructive estimation of crop N-substance nutrition.
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Saccharum , Grão Comestível , Aprendizado de Máquina , Nitrogênio , Estado NutricionalRESUMO
Aroma is an important aspect of wine quality and consumer appreciation. The volatile organic compounds (VOCs) and olfactory profiles of Merlot dry red wines from the Eastern Foothill of Helan Mountain (EFHM) were analyzed using gas chromatography-mass spectrometry and quantitative descriptive analysis. The results showed that Merlot wines from EFHM were characterized by intense flavors of drupe and tropical fruits compared with the Gansu region. Nineteen VOCs were defined as essential compounds contributing to the aroma characteristics of the Merlot wines through gas chromatography-olfactometry/mass spectrometry and odor activity value analysis. Predominantly, geranyl isovalerate, which contributed to the herbal odors of the Merlot wines, was detected in the grape wine of EFHM for the first time. The addition experiment revealed that geranyl isovalerate influenced the aroma quality of wine by increasing herbal odors and enhancing the olfactory intensities of tropical fruits. These results are helpful for further understanding the aroma of Merlot wines from EFHM and improving the quality of wine aromas.
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Vitis , Compostos Orgânicos Voláteis , Vinho , Odorantes/análise , Vinho/análise , Olfato , Vitis/química , Compostos Orgânicos Voláteis/análise , ChinaRESUMO
Li-CO2 battery with high energy density has aroused great interest recently, large-scale applications are hindered by the limited cathode catalysis performance and execrably cycle performance. Herein, Mo3 P/Mo Mott-Schottky heterojunction nanorod electrocatalyst with abundant porous structure is fabricated and served as cathodes for Li-CO2 batteries. The Mo3 P/Mo cathodes exhibit ultra-high discharge specific capacity of 10 577 mAh g-1 , low polarization voltage of 0.15 V, and high energy efficiency of up to 94.7%. Mott-Schottky heterojunction formed by Mo and Mo3 P drives electron transfer and optimizes the surface electronic structure, which is beneficial to accelerate the interface reaction kinetics. Distinctively, during the discharge process, the C2 O4 2- intermediates combine with Mo atoms to form a stable Mo-O coupling bridge on the catalyst surface, which effectively facilitate the formation and stabilization of Li2 C2 O4 products. In addition, the construction of the Mo-O coupling bridge between the Mott-Schottky heterojunction and Li2 C2 O4 promotes the reversible formation and decomposition of discharge products and optimizes the polarization performance of the Li-CO2 battery. This work provides another pathway for the development of heterostructure engineering electrocatalysts for high-performance Li-CO2 batteries.
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Anthocyanins, total phenols, soluble sugar and fruit shape plays a significant role in determining the distinct fruit quality and customer preference. However, for the majority of fruit species, little is known about the transcriptomics and underlying regulatory networks that control the generation of overall quality during fruit growth and ripening. This study incorporated the quality-related transcriptome data from 6 ecological zones across 3 fruit development and maturity phases of Chardonnay cultivars. With the help of this dataset, we were able to build a complex regulatory network that may be used to identify important structural genes and transcription factors that control the anthocyanins, total phenols, soluble sugars and fruit shape in grapes. Overall, our findings set the groundwork to improve grape quality in addition to offering novel views on quality control during grape development and ripening.