57 research outputs found

    Analysis of the optimal operation frequency with lowest time-delay jitter for an electrically triggered field-distortion spark gap

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    This work was stimulated by the assumption that for a gas-filled spark gap closing switch operating at a high repetition frequency, there is an optimal frequency range in which the time-delay jitter reaches a minimum value. The experiments to test this assumption use an electrically triggered, field-distortion spark gap filled with the SF6/N2 gas mixture. The results show that indeed, the time-delay jitter decreases for a range of frequencies for which the filling gas can substantially restore the interelectrode insulation before increasing at a higher operation frequency. The experimental results demonstrate the correctness of the abovepresented assumption: the time-delay jitter of the field-distortion spark gap has its minimum when the unit operates in the repetition frequency range between 20 and 30 Hz. Since the recovery time depends on the gas species and the gap distance, the optimum operation frequency range should also vary depending on the spark-gap distance and the filling gas properties

    Controlled Growth of Metal–Organic Framework on Upconversion Nanocrystals for NIR-Enhanced Photocatalysis

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    Development of MOF-based photocatalysts is intriguing research due to their structural flexibility and tremendous catalytic sites, whereas most MOFs only can take use of UV/visible light and lack of response to NIR light. Herein, we present a facile approach to integrate upconversion nanoparticles (UCNPs) with MOF to build a NIR-responsive composite photocatalyst. The MOF shell with controllable thickness can be grown on the UCNPs, thus exhibiting tunable photocatalytic activities under NIR irradiation. Furthermore, we extend visible absorption of the MOF shell by adding −NH<sub>2</sub> groups so that the composite photocatalysts have a better utilization of UC emissions and sunlight to improve their activities. The developed composite photocatalysts have been characterized by XRD, TEM, PL, etc., and their photocatalytic performances were systematically explored. The formation and working mechanism of the composite photocatalysts were also elucidated

    Multifunctional Theranostics for Dual-Modal Photodynamic Synergistic Therapy via Stepwise Water Splitting

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    Combined therapy using multiple approaches has been demonstrated to be a promising route for cancer therapy. To achieve enhanced antiproliferation efficacy under hypoxic condition, here we report a novel hybrid system by integrating dual-model photodynamic therapies (dual-PDT) in one system. First, we attached core–shell structured up-conversion nanoparticles (UCNPs, NaGdF<sub>4</sub>:Yb,Tm@NaGdF<sub>4</sub>) on graphitic-phase carbon nitride (<i>g-</i>C<sub>3</sub>N<sub>4</sub>) nanosheets (one photosensitizer). Then, the as-fabricated nanocomposite and carbon dots (another photosensitizer) were assembled in ZIF-8 metal–organic frameworks through an in situ growth process, realizing the dual-photosensitizer hybrid system employed for PDT via stepwise water splitting. In this system, the UCNPs can convert deep-penetration and low-energy near-infrared light to higher-energy ultraviolet–visible emission, which matches well with the absorption range of the photosensitizers for reactive oxygen species (ROS) generation without sacrificing its efficacy under ZIF-8 shell protection. Furthermore, the UV light emitted from UCNPs allows successive activation of <i>g</i>-C<sub>3</sub>N<sub>4</sub> and carbon dots, and the visible light from carbon dots upon UV light excitation once again activate <i>g</i>-C<sub>3</sub>N<sub>4</sub> to produce ROS, which keeps the principle of energy conservation thus achieving maximized use of the light. This dual-PDT system exhibits excellent antitumor efficiency superior to any single modality, verified vividly by in vitro and in vivo assay

    Table_1_Oriental melon roots metabolites changing response to the pathogen of Fusarium oxysporum f. sp. melonis mediated by Trichoderma harzianum.XLSX

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    IntroductionTrichoderma spp. is a recognized bio-control agent that promotes plant growth and enhances resistance against soil-borne diseases, especially Fusarium wilt. It is frequently suggested that there is a relationship between resistance to melon wilt and changes in soil microbiome structures in the rhizosphere with plant metabolites. However, the exact mechanism remains unclear.MethodThis study aims to investigate the effects of Trichoderma application on the metabolic pathway of oriental melon roots in response to Fusarium oxysporum f. sp. melonis in a pot experiment. The experiment consisted of three treatments, namely water-treated (CK), FOM-inoculated (KW), and Trichoderma-applied (MM) treatments, that lasted for 25 days. Ultra-performance liquid chromatography-electron spray ionization-mass spectrometry (UPLC-ESI-MS) was used to analyze the compounds in melon roots.ResultsThe results show that Trichoderma harzianum application resulted in a reduction in the severity of oriental melon Fusarium wilt. A total of 416 distinct metabolites, categorized into four groups, were detected among the 886 metabolites analyzed. Additionally, seven differential metabolites were identified as key compounds being accumulated after inoculation with Fusarium oxysporum f. sp. melonis (FOM) and Trichoderma. The mechanism by which Trichoderma enhanced melon's resistance to Fusarium wilt was primarily associated with glycolysis/gluconeogenesis, phenylpropanoid biosynthesis, flavone and flavonol biosynthesis, and the biosynthesis of cofactors pathway. In comparison with the treatments of CK and MM, the KW treatment increased the metabolites of flavone and flavonol biosynthesis, suggesting that oriental melon defended against pathogen infection by increasing flavonol biosynthesis in the KW treatment, whereas the application of Trichoderma harzianum decreased pathogen infection while also increasing the biosynthesis of glycolysis/gluconeogenesis and biosynthesis of cofactors pathway, which were related to growth. This study also aims to enhance our understanding of how melon responds to FOM infection and the mechanisms by which Trichoderma harzianum treatment improves melon resistance at the metabolic level.</p

    Image_3_Oriental melon roots metabolites changing response to the pathogen of Fusarium oxysporum f. sp. melonis mediated by Trichoderma harzianum.JPEG

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    IntroductionTrichoderma spp. is a recognized bio-control agent that promotes plant growth and enhances resistance against soil-borne diseases, especially Fusarium wilt. It is frequently suggested that there is a relationship between resistance to melon wilt and changes in soil microbiome structures in the rhizosphere with plant metabolites. However, the exact mechanism remains unclear.MethodThis study aims to investigate the effects of Trichoderma application on the metabolic pathway of oriental melon roots in response to Fusarium oxysporum f. sp. melonis in a pot experiment. The experiment consisted of three treatments, namely water-treated (CK), FOM-inoculated (KW), and Trichoderma-applied (MM) treatments, that lasted for 25 days. Ultra-performance liquid chromatography-electron spray ionization-mass spectrometry (UPLC-ESI-MS) was used to analyze the compounds in melon roots.ResultsThe results show that Trichoderma harzianum application resulted in a reduction in the severity of oriental melon Fusarium wilt. A total of 416 distinct metabolites, categorized into four groups, were detected among the 886 metabolites analyzed. Additionally, seven differential metabolites were identified as key compounds being accumulated after inoculation with Fusarium oxysporum f. sp. melonis (FOM) and Trichoderma. The mechanism by which Trichoderma enhanced melon's resistance to Fusarium wilt was primarily associated with glycolysis/gluconeogenesis, phenylpropanoid biosynthesis, flavone and flavonol biosynthesis, and the biosynthesis of cofactors pathway. In comparison with the treatments of CK and MM, the KW treatment increased the metabolites of flavone and flavonol biosynthesis, suggesting that oriental melon defended against pathogen infection by increasing flavonol biosynthesis in the KW treatment, whereas the application of Trichoderma harzianum decreased pathogen infection while also increasing the biosynthesis of glycolysis/gluconeogenesis and biosynthesis of cofactors pathway, which were related to growth. This study also aims to enhance our understanding of how melon responds to FOM infection and the mechanisms by which Trichoderma harzianum treatment improves melon resistance at the metabolic level.</p

    Monodisperse Lanthanide Fluoride Nanocrystals: Synthesis and Luminescent Properties

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    Three types of high-quality, monodisperse lanthanide fluoride colloidal nanocrystals (NCs) including LnF<sub>3</sub> (Ln = La–Pr), NaLnF<sub>4</sub> (Ln = Sm–Er), and Na<sub>5</sub>Ln<sub>9</sub>F<sub>32</sub> (Ln = Tm–Lu) with two crystal phases (hexagonal and cubic) and a rich variety of morphologies have been synthesized in high boiling organic solvents oleic acid and 1-octadecene, <i>via</i> a thermal decomposition pathway. The as-synthesized NCs were well characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FT-IR), and photoluminescence (PL) spectra, respectively. It is found that the as-synthesized NCs consist of monodisperse nanoparticles with diverse shapes and narrow size distribution, which can easily disperse in nonpolar cyclohexane solvent. Additionally, a possible mechanism of NC nucleation and growth has been proposed. The results reveal that the formation of monodisperse NCs closely correlates with the inherent nature of lanthanide series from La to Lu. Under 980 nm NIR excitation, as-synthesized Yb<sup>3+</sup>/Ln<sup>3+</sup> (Ln = Er, Tm, Ho)-doped NaGdF<sub>4</sub> and Na<sub>5</sub>Lu<sub>9</sub>F<sub>32</sub> colloidal NCs show the respective characteristic up-conversion (UC) emissions of Er<sup>3+</sup>, Tm<sup>3+</sup>, and Ho<sup>3+</sup>, which are promising for applications in biolabels, bioimaging, displays, and other optical technologies

    Image_4_Oriental melon roots metabolites changing response to the pathogen of Fusarium oxysporum f. sp. melonis mediated by Trichoderma harzianum.JPEG

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    IntroductionTrichoderma spp. is a recognized bio-control agent that promotes plant growth and enhances resistance against soil-borne diseases, especially Fusarium wilt. It is frequently suggested that there is a relationship between resistance to melon wilt and changes in soil microbiome structures in the rhizosphere with plant metabolites. However, the exact mechanism remains unclear.MethodThis study aims to investigate the effects of Trichoderma application on the metabolic pathway of oriental melon roots in response to Fusarium oxysporum f. sp. melonis in a pot experiment. The experiment consisted of three treatments, namely water-treated (CK), FOM-inoculated (KW), and Trichoderma-applied (MM) treatments, that lasted for 25 days. Ultra-performance liquid chromatography-electron spray ionization-mass spectrometry (UPLC-ESI-MS) was used to analyze the compounds in melon roots.ResultsThe results show that Trichoderma harzianum application resulted in a reduction in the severity of oriental melon Fusarium wilt. A total of 416 distinct metabolites, categorized into four groups, were detected among the 886 metabolites analyzed. Additionally, seven differential metabolites were identified as key compounds being accumulated after inoculation with Fusarium oxysporum f. sp. melonis (FOM) and Trichoderma. The mechanism by which Trichoderma enhanced melon's resistance to Fusarium wilt was primarily associated with glycolysis/gluconeogenesis, phenylpropanoid biosynthesis, flavone and flavonol biosynthesis, and the biosynthesis of cofactors pathway. In comparison with the treatments of CK and MM, the KW treatment increased the metabolites of flavone and flavonol biosynthesis, suggesting that oriental melon defended against pathogen infection by increasing flavonol biosynthesis in the KW treatment, whereas the application of Trichoderma harzianum decreased pathogen infection while also increasing the biosynthesis of glycolysis/gluconeogenesis and biosynthesis of cofactors pathway, which were related to growth. This study also aims to enhance our understanding of how melon responds to FOM infection and the mechanisms by which Trichoderma harzianum treatment improves melon resistance at the metabolic level.</p

    Image_1_Oriental melon roots metabolites changing response to the pathogen of Fusarium oxysporum f. sp. melonis mediated by Trichoderma harzianum.JPEG

    No full text
    IntroductionTrichoderma spp. is a recognized bio-control agent that promotes plant growth and enhances resistance against soil-borne diseases, especially Fusarium wilt. It is frequently suggested that there is a relationship between resistance to melon wilt and changes in soil microbiome structures in the rhizosphere with plant metabolites. However, the exact mechanism remains unclear.MethodThis study aims to investigate the effects of Trichoderma application on the metabolic pathway of oriental melon roots in response to Fusarium oxysporum f. sp. melonis in a pot experiment. The experiment consisted of three treatments, namely water-treated (CK), FOM-inoculated (KW), and Trichoderma-applied (MM) treatments, that lasted for 25 days. Ultra-performance liquid chromatography-electron spray ionization-mass spectrometry (UPLC-ESI-MS) was used to analyze the compounds in melon roots.ResultsThe results show that Trichoderma harzianum application resulted in a reduction in the severity of oriental melon Fusarium wilt. A total of 416 distinct metabolites, categorized into four groups, were detected among the 886 metabolites analyzed. Additionally, seven differential metabolites were identified as key compounds being accumulated after inoculation with Fusarium oxysporum f. sp. melonis (FOM) and Trichoderma. The mechanism by which Trichoderma enhanced melon's resistance to Fusarium wilt was primarily associated with glycolysis/gluconeogenesis, phenylpropanoid biosynthesis, flavone and flavonol biosynthesis, and the biosynthesis of cofactors pathway. In comparison with the treatments of CK and MM, the KW treatment increased the metabolites of flavone and flavonol biosynthesis, suggesting that oriental melon defended against pathogen infection by increasing flavonol biosynthesis in the KW treatment, whereas the application of Trichoderma harzianum decreased pathogen infection while also increasing the biosynthesis of glycolysis/gluconeogenesis and biosynthesis of cofactors pathway, which were related to growth. This study also aims to enhance our understanding of how melon responds to FOM infection and the mechanisms by which Trichoderma harzianum treatment improves melon resistance at the metabolic level.</p

    Image_2_Oriental melon roots metabolites changing response to the pathogen of Fusarium oxysporum f. sp. melonis mediated by Trichoderma harzianum.JPEG

    No full text
    IntroductionTrichoderma spp. is a recognized bio-control agent that promotes plant growth and enhances resistance against soil-borne diseases, especially Fusarium wilt. It is frequently suggested that there is a relationship between resistance to melon wilt and changes in soil microbiome structures in the rhizosphere with plant metabolites. However, the exact mechanism remains unclear.MethodThis study aims to investigate the effects of Trichoderma application on the metabolic pathway of oriental melon roots in response to Fusarium oxysporum f. sp. melonis in a pot experiment. The experiment consisted of three treatments, namely water-treated (CK), FOM-inoculated (KW), and Trichoderma-applied (MM) treatments, that lasted for 25 days. Ultra-performance liquid chromatography-electron spray ionization-mass spectrometry (UPLC-ESI-MS) was used to analyze the compounds in melon roots.ResultsThe results show that Trichoderma harzianum application resulted in a reduction in the severity of oriental melon Fusarium wilt. A total of 416 distinct metabolites, categorized into four groups, were detected among the 886 metabolites analyzed. Additionally, seven differential metabolites were identified as key compounds being accumulated after inoculation with Fusarium oxysporum f. sp. melonis (FOM) and Trichoderma. The mechanism by which Trichoderma enhanced melon's resistance to Fusarium wilt was primarily associated with glycolysis/gluconeogenesis, phenylpropanoid biosynthesis, flavone and flavonol biosynthesis, and the biosynthesis of cofactors pathway. In comparison with the treatments of CK and MM, the KW treatment increased the metabolites of flavone and flavonol biosynthesis, suggesting that oriental melon defended against pathogen infection by increasing flavonol biosynthesis in the KW treatment, whereas the application of Trichoderma harzianum decreased pathogen infection while also increasing the biosynthesis of glycolysis/gluconeogenesis and biosynthesis of cofactors pathway, which were related to growth. This study also aims to enhance our understanding of how melon responds to FOM infection and the mechanisms by which Trichoderma harzianum treatment improves melon resistance at the metabolic level.</p

    La(OH)<sub>3</sub>:Ln<sup>3+</sup> and La<sub>2</sub>O<sub>3</sub>:Ln<sup>3+</sup> (Ln = Yb/Er, Yb/Tm, Yb/Ho) Microrods: Synthesis and Up-conversion Luminescence Properties

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    One-dimensional La­(OH)<sub>3</sub>:Ln<sup>3+</sup> (Ln = Yb/Er, Yb/Tm, Yb/Ho) microrods have been successfully synthesized using molten composite-hydroxide (NaOH/KOH) as a solvent. La<sub>2</sub>O<sub>3</sub>:Ln<sup>3+</sup> nanostructures with retained striplike shape were achieved by a subsequent annealing process. The phase, structure, morphology, and fluorescent properties have been well investigated by various techniques. It is found that the reaction time plays a key role in confining the growth of the microrods. Both La­(OH)<sub>3</sub>:Ln<sup>3+</sup> and La<sub>2</sub>O<sub>3</sub>:Ln<sup>3+</sup> nanostructures have rodlike shapes with a typical width of 50–400 nm. The up-conversion (UC) photoluminescence (PL) properties of the samples have been studied in detail. Under 980 nm laser excitation, both La­(OH)<sub>3</sub>:Ln<sup>3+</sup> and La<sub>2</sub>O<sub>3</sub>:Ln<sup>3+</sup> microrods exhibit the characteristic emissions of Er<sup>3+</sup>, Tm<sup>3+</sup>, and Ho<sup>3+</sup> and give green, blue, and blackish green emission colors, respectively. Additionally, the doping concentration of Yb<sup>3+</sup> has been optimized by fixing the Er<sup>3+</sup> concentration. It should be noted that the up-conversion emission of La<sub>2</sub>O<sub>3</sub>:Er<sup>3+</sup> microrods can be significantly improved in comparison with that of their bulk counterpart under the same excitation conditions
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