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1.
RSC Adv ; 14(22): 15656-15663, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38746835

RESUMEN

Carbon-based catalysts catalyze methane decomposition to produce hydrogen is a very attractive technical route. Carbon black in carbon-based catalysts has the advantages of high catalytic activity, good stability and better tolerance to toxic impurities such as sulphur in the feedstock, which has become a hot topic of research for many scientists. In this work, the effect of heat treatment on the structural and surface properties of carbon blacks and their catalytic performance in hydrogen production from methane decomposition was investigated. A commercial carbon blacks N110 was selected to heat treatment with nitrogen or carbon dioxide atmosphere at 850 °C, respectively. The Raman spectrums indicated that the graphitization degree of modified carbon under two atmospheres were promoted with the treatment time increasing. BET results revealed that the specific surface area of the carbon black treated under carbon dioxide increased, while the specific surface area was unchanged for that of the carbon black treated under nitrogen. The catalytic test of the two modified carbon blacks for methane decomposition exhibited the almost same activity, which meant that the graphitization degree of carbon black is the key factor for methane decomposition rather than the specific surface area. It was suggested that highly graphitized carbon black could be used as the potential catalysts for hydrogen production from methane decomposition.

2.
J Colloid Interface Sci ; 668: 264-271, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38678882

RESUMEN

Electricity-driven nitrate (NO3-) to ammonia (NH3) conversion presents a unique opportunity to simultaneously eliminate nitrate from sewage while capturing ammonia. However, the Faradaic efficiency and ammonia yield in this eight-electron process remain unsatisfactory, underscoring the critical need for more effective electrocatalysts. In this study, a RuCo alloy nanosheets electrodeposited on pinewood-derived three-dimensional porous carbon (RuCo@TDC) is introduced as a highly-efficient electrocatalyst for the nitrate reduction reaction. The RuCo@TDC catalyst exhibits superior electrocatalytic performance, achieving the highest NH3 yield of 2.02 ± 0.11 mmol h-1 cm-2 at -0.6 V versus the reversible hydrogen electrode (vs. RHE) and the highest Faradaic efficiency of 95.7 ± 0.8 % at -0.2 V vs. RHE in an electrolyte mixture of 0.1 M KOH and 0.1 M KNO3. Furthermore, the Zn-NO3- battery using RuCo@TDC as the cathode provides a maximum power density of 2.46 mW cm-2 and a satisfactory NH3 yield of 1110 µg h-1 cm-2.

3.
Nat Commun ; 15(1): 3520, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664402

RESUMEN

The root-associated microbiota plays an important role in the response to environmental stress. However, the underlying mechanisms controlling the interaction between salt-stressed plants and microbiota are poorly understood. Here, by focusing on a salt-tolerant plant wild soybean (Glycine soja), we demonstrate that highly conserved microbes dominated by Pseudomonas are enriched in the root and rhizosphere microbiota of salt-stressed plant. Two corresponding Pseudomonas isolates are confirmed to enhance the salt tolerance of wild soybean. Shotgun metagenomic and metatranscriptomic sequencing reveal that motility-associated genes, mainly chemotaxis and flagellar assembly, are significantly enriched and expressed in salt-treated samples. We further find that roots of salt stressed plants secreted purines, especially xanthine, which induce motility of the Pseudomonas isolates. Moreover, exogenous application for xanthine to non-stressed plants results in Pseudomonas enrichment, reproducing the microbiota shift in salt-stressed root. Finally, Pseudomonas mutant analysis shows that the motility related gene cheW is required for chemotaxis toward xanthine and for enhancing plant salt tolerance. Our study proposes that wild soybean recruits beneficial Pseudomonas species by exudating key metabolites (i.e., purine) against salt stress.


Asunto(s)
Glycine max , Raíces de Plantas , Pseudomonas , Rizosfera , Pseudomonas/genética , Pseudomonas/metabolismo , Glycine max/microbiología , Glycine max/metabolismo , Glycine max/genética , Raíces de Plantas/microbiología , Raíces de Plantas/metabolismo , Microbiota/efectos de los fármacos , Purinas/metabolismo , Purinas/farmacología , Estrés Salino/genética , Quimiotaxis/genética , Tolerancia a la Sal/genética , Microbiología del Suelo , Xantina/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética
4.
ACS Appl Mater Interfaces ; 16(15): 19730-19741, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38591140

RESUMEN

Metal-organic framework materials can be converted into carbon-based nanoporous materials by pyrolysis, which have a wide range of applications in energy storage. Here, we design special interface engineering to combine the carbon skeleton and nitrogen-doped carbon nanotubes (CNTs) with the transition metal compounds (TMCs) well, which mitigates the bulk effect of the TMCs and improves the conductivity of the electrodes. Zeolitic imidazolate framework-67 is used as a precursor to form a carbon skeleton and a large number of nitrogen-doped CNTs by pyrolysis followed by the in situ formation of Co3O4 and CoS2, and finally, Co3O4@CNTs and CoS2@CNTs are synthesized. The obtained anode electrodes exhibit a long cycle life and high-rate properties. In lithium-ion batteries (LIBs), Co3O4@CNTs have a high capacity of 581 mAh g-1 at a high current of 5 A g-1, and their reversible capacity is still 1037.6 mAh g-1 after 200 cycles at 1 A g-1. In sodium-ion batteries (SIBs), CoS2@CNTs have a capacity of 859.9 mAh g-1 at 0.1 A g-1 and can be retained at 801.2 mAh g-1 after 50 cycles. The unique interface engineering and excellent electrochemical properties make them ideal anode materials for high-rate, long-life LIBs and SIBs.

5.
Food Chem Toxicol ; 188: 114666, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38621509

RESUMEN

This work was designed to investigate the neurotoxic effects of the typical plasticizer dibutyl phthalate (DBP) using zebrafish larvae as a model. The results of exhibited that zebrafish larvae exposed to DBP at concentrations of 5 µg/L and 10 µg/L exhibited brain malformations (24 h) and behavioral abnormalities (72 h). After 72 h of exposure to DBP, microglia in the brain were over-activated, reactive oxygen species (ROS) formation was increased, and apoptosis was observed. Meanwhile, it was found that neurons exhibited impaired mitochondrial structure, absent mitochondrial membrane potential and up-regulated autophagy. Further comprehensive biochemical analyses and RNA-Seq, validated by RT-qPCR, glutamate metabolism and PPAR signaling pathway were significantly enriched in the DBP stress group, this may be the main reason for the disruption of glycolysis/gluconeogenesis processes and the reduction of energy substrates for the astrocyte-neuron lactate shuttle (ANLS). In addition, the DBP-exposed group showed aberrant activation of endoplasmic reticulum (ER) stress signaling pathway, which may be related to ROS as well as neuronal apoptosis and autophagy. In conclusion, DBP-induced neurotoxicity may be the combined result of insufficient neuronal energy acquisition, damage to mitochondrial structure, apoptosis and autophagy. These results provide a theoretical basis for understanding the neurotoxic effects of DBP.


Asunto(s)
Apoptosis , Dibutil Ftalato , Larva , Neuronas , Pez Cebra , Animales , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Dibutil Ftalato/toxicidad , Larva/efectos de los fármacos , Larva/metabolismo , Apoptosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Metabolismo Energético/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Autofagia/efectos de los fármacos , Plastificantes/toxicidad , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos
6.
J Environ Manage ; 353: 120187, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38310792

RESUMEN

The environmental pollution of water is one of the problems that have plagued human society. The bimetallic nanoscale zero-valent iron (BnZVI) technology has increased wide attention owing to its high performance for water treatment and soil remediation. In recent years, the BnZVI technology based on the development of nZVI has been further developed. The material chemistry, synthesis methods, and immobilization or surface stabilization of bimetals are discussed. Further, the data of BnZVI (Fe/Ni, Fe/Cu, Fe/Pd) articles that have been studied more frequently in the last decade are summarized in terms of the types of contaminants and the number of research literatures on the same contaminants. Five contaminants including trichloroethylene (TCE), Decabromodi-phenyl Ether (BDE209), chromium (Cr(VI)), nitrate and 2,4-dichlorophenol (2,4-DCP) were selected for in-depth discussion on their influencing factors and removal or degradation mechanisms. Herein, comprehensive views towards mechanisms of BnZVI applications including adsorption, hydrodehalogenation and reduction are provided. Particularly, some ambiguous concepts about formation of micro progenitor cell, production of hydrogen radicals (H·) and H2 and the electron transfer are highlighted. Besides, in-depth discussion of selectivity for N2 from nitrates and co-precipitation of chromium are emphasized. The difference of BnZVI is also discussed.


Asunto(s)
Hierro , Contaminantes Químicos del Agua , Humanos , Descontaminación , Contaminantes Químicos del Agua/análisis , Contaminación Ambiental , Cromo/análisis , Adsorción , Nitratos
7.
Microbiol Res ; 280: 127598, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38176360

RESUMEN

Microbial co-culture has proven to be an effective way to improve the ability of microorganisms to biocontrol. However, the interactive mechanisms of co-cultural microbes, especially between fungi and bacteria, have rarely been studied. By comparative analysis of morphology, transcriptomics and metabolomics, the interactive mechanisms of a sequential co-culture system of Trichoderma asperellum HG1 and Bacillus subtilis Tpb55 was explored in this study. The results revealed that co- culture has no significant effect on the growth and cell morphology of the two strains, but lead to mycelium wrinkling of HG1. RNA-seq analysis showed that co-culture significantly upregulated the HG1 genes concerning amino acid degradation and metabolism, proteolysis, resisting environmental stress, cell homeostasis, glycolysis, the glyoxylate cycle, and the citric acid (TCA) cycle, while Tpb55 genes related to cell homeostasis, spore formation and membrane fluidization were significantly upregulated, but genes associating to TCA, glycolytic cycles and fatty acid ß-oxidation were significantly downregulated. Metabolomic results revealed that some amino acids related to energy metabolism were significantly altered in HG1, whereas palmitic acid, which is related to cell membrane functions, was upregulated in Tpb55. These results indicated that HG1 could interfere with carbon metabolism and cell membrane fluidity, but accelerate spore formation of Tpb55. Biophysical assays further convinced that co-culture could decrease ATP content and inhibit ATPase activity in HG1, and could promote spore formation and reduce the cell membrane fluidity of Tpb55. In addition, co-culture also accelerated the production of intracellular anti-oomycete compound octhilinone. The above results indicate that HG1 and Tpb55 are mainly in a competitive relationship in the co culture system. These findings provide new insights for understanding the interaction mechanism between co cultured microbes.


Asunto(s)
Bacillus subtilis , Hypocreales , Trichoderma , Técnicas de Cocultivo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Perfilación de la Expresión Génica , Metabolómica , Trichoderma/metabolismo
8.
Small ; 20(1): e2305322, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37641186

RESUMEN

Solid-state batteries have become the most anticipated option for compatibility with high-energy density and safety. In situ polymerization, a novel strategy for the construction of solid-state systems, has extended its application from solid polymer electrolyte systems to other solid-state systems. This review summarizes the application of in situ polymerization strategies in solid-state batteries, which covers the construction of polymer, the formation of the electrolyte system, and the design of the full cell. For the polymer skeleton, multiple components and structures are being chosen. In the construction of solid polymer electrolyte systems, the choice of initiator for in situ polymerization is the focus of this review. New initiators, represented by lithium salts and additives, are the preferred choice because of their ability to play more diverse roles, while the coordination with other components can also improve the electrical properties of the system and introduce functionalities. In the construction of entire solid-state battery systems, the application of in situ polymerization to structure construction, interface construction, and the use of separators with multiplex functions has brought more possibilities for the development of various solid-state systems and even the perpetuation of liquid electrolytes.

9.
J Environ Manage ; 349: 119488, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37939476

RESUMEN

Rhizosphere microbiomes play an important role in enhancing plant salt tolerance and are also commonly employed as bio-inoculants in soil remediation processes. Cultivated soybean (Glycine max) is one of the major oilseed crops with moderate salt tolerance. However, the response of rhizosphere microbes me to salt stress in soybean, as well as their potential application in saline soil reclamation, has been rarely reported. In this study, we first investigated the microbial communities of salt-treated and non-salt-treated soybean by 16S rRNA gene amplicon sequencing. Then, the potential mechanism of rhizosphere microbes in enhancing the salt tolerance of soybean was explored based on physiological analyses and transcriptomic sequencing. Our results suggested that Ensifer and Novosphingobium were biomarkers in salt-stressed soybean. One corresponding strain, Ensifer sp. GMS14, showed remarkable growth promoting characteristics. Pot experiments showed that GMS14 significantly improved the growth performance of soybean in saline soils. Strain GMS14 alleviated sodium ions (Na+) toxicity by maintaining low a Na+/K+ ratio and promoted nitrogen (N) and phosphorus (P) uptake by soybean in nutrient-deficient saline soils. Transcriptome analyses indicated that GMS14 improved plant salt tolerance mainly by ameliorating salt stress-mediated oxidative stress. Interestingly, GMS14 was evidenced to specifically suppress hydrogen peroxide (H2O2) production to maintain reactive oxygen species (ROS) homeostasis in plants under salt stress. Field experiments with GMS14 applications showed its great potential in saline soil reclamation, as evidenced by the increased biomass and nodulation capacity of GMS14-inoculated soybean. Overall, our findings provided valuable insights into the mechanisms underlying plant-microbes interactions, and highlighted the importance of microorganisms recruited by salt-stressed plant in the saline soil reclamation.


Asunto(s)
Tolerancia a la Sal , Suelo , Tolerancia a la Sal/genética , Glycine max/genética , Peróxido de Hidrógeno , ARN Ribosómico 16S , Sodio
10.
J Agric Food Chem ; 71(51): 20713-20723, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38095326

RESUMEN

Two new terrein derivatives, aspergilethers A and B (1 and 2), two known analogues (3 and 4), and three known butenolides (5-7) were isolated from the endophyte Aspergillus terreus HT5. Their structures were determined by spectroscopic analysis and ECD and NMR calculations. Interestingly, 1 and 2 had unpresented medium aliphatic side chains in terrein derivatives, with different absolute configurations at C-7, which was very scarce. (+)-Terrein (3) exhibited potent postemergence phytotoxicity toward Amaranthaceae, Portulacaceae, and Fabaceae, with MIC values of 250-1000 µg/mL. Transcriptome analysis and qRT-PCR suggested that (+)-terrein induced the transcriptional expression of aging-related genes to accelerate organ senescence and stimulated plant detoxification response. The conjugated system between keto carbonyl and double bonds in the cyclopentenone ring and side chain, and the configurations of C-2 and C-3, played critical roles in the phytotoxicity of terrein derivatives. Meanwhile, 3 was first reported to display moderate antioomycetes activity toward Phytophthora nicotiana.


Asunto(s)
Antiinfecciosos , Toxinas Biológicas , Aspergillus/metabolismo , Antiinfecciosos/metabolismo , Toxinas Biológicas/metabolismo , Estructura Molecular
11.
J Environ Manage ; 345: 118574, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37423189

RESUMEN

Soil salinization is a serious global environmental problem affecting sustainable development of agriculture. Legumes are excellent candidates for the phytoremediation of saline soils; however, how soil microbes mediate the amelioration of coastal saline ecosystems is unknown. In this study, two salt-tolerant legumes, Glycine soja and Sesbania cannabina were planted in coastal saline soil for three years. Soil nutrient availability and microbiota structure (including bacteria, fungi, and diazotrophs) were compared between the phytoremediated soils and control soil (barren land). Planting legumes reduced soil salinity, and increased total carbon, total nitrogen, and NO3--N contents. Among the soil microbiota, some nitrogen-fixing bacteria (e.g., Azotobacter) were enriched in legumes, which were probably responsible for soil nitrogen accumulation. The complexity of the bacterial, fungal, and diazotrophic networks increased significantly from the control to the phytoremediated soils, suggesting that the soil microbial community formed closer ecological interactions during remediation. Furthermore, the dominant microbial functions were chemoheterotrophy (24.75%) and aerobic chemoheterotrophy (21.97%) involved in the carbon cycle, followed by nitrification (13.68%) and aerobic ammonia oxidation (13.34%) involved in the nitrogen cycle. Overall, our findings suggested that G. soja and S. cannabina legumes were suitable for ameliorating saline soils as they decreased soil salinity and increased soil nutrient content, with microorganisms especially nitrogen-fixing bacteria, playing an important role in this remediation process.


Asunto(s)
Fabaceae , Microbiota , Suelo/química , Bacterias , Verduras , Nitrógeno , Microbiología del Suelo
12.
J Chromatogr A ; 1705: 464164, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37419017

RESUMEN

Metal-organic framework/silica composite (SSU) were prepared by growing UiO-66 on the amino-functionalized SiO2 core-shell spheres (SiO2@dSiO2) via a simple one-pot synthesis approach. By controlling the concentration of Zr4+, the obtained SSU have two different morphologies: spheres-on-sphere and layer-on-sphere. The spheres-on-sphere structure is formed by the aggregation of UiO-66 nanocrystals on the surface of SiO2@dSiO2 spheres. SSU-5 and SSU-20, which contain spheres-on-sphere composites have mesopores with a pore size of about 45 nm in addition to the characteristic micropores of UiO-66 with a pore size of 1 nm. In addition, UiO-66 nanocrystals were grown both inside and outside the pores of SiO2@dSiO2, resulting in a 27% loading of UiO-66 in the SSU. The layer-on-sphere is the surface of SiO2@dSiO2 covered with a layer of UiO-66 nanocrystals. SSU with this structure has only a characteristic pore size of about 1 nm belonging to UiO-66 and is therefore not suitable as a packed stationary phase for high performance liquid chromatography. The SSU spheres were packed into columns and tested for the separation of xylene isomers, aromatics, biomolecules, acidic and basic analytes. With both micropores and mesopores, SSU with spheres-on-sphere structure achieved baseline separation of both small and large molecules. Efficiencies up to 48,150, 50,452 and 41,318 plates m - 1 were achieved for m-xylene, p-xylene and o-xylene, respectively. The relative standard deviations of the retention times of anilines for run-to-run, day-to-day and column-to-column were all less than 6.1%. The results show that the SSU with spheres-on-sphere structure has great potential for high performance chromatographic separation.


Asunto(s)
Estructuras Metalorgánicas , Ácidos Ftálicos , Cromatografía Líquida de Alta Presión/métodos , Dióxido de Silicio/química
13.
Food Chem ; 424: 136340, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37220685

RESUMEN

In this study, microwave infrared vibrating bed drying (MIVBD) method was used to dry ginger and the key characteristics of the product were determined, in terms of drying characteristics, microstructure, phenolic and flavonoid contents, ascorbic acid (AA), sugar content, and antioxidant properties. The mechanism of sample browning during drying was investigated. The results showed that increased infrared temperature and microwave power increased the drying rate and caused microstructure damage to the samples. At the same time, which caused the degradation of the active ingredients, promoted Maillard reaction between reducing sugar and amino acid, and caused the increase of 5-hydroxymethylfurfural, then the degree of browning increased. The AA reacted with amino acid to also caused browning. Antioxidant activity was significantly affected by AA and phenolics (r > 0.95). The quality and efficiency of drying can be effectively improved by MIVBD, and the browning can be reduced by controlling infrared temperature and microwave power.


Asunto(s)
Zingiber officinale , Zingiber officinale/química , Microondas , Antioxidantes/química , Desecación/métodos , Ácido Ascórbico/química , Fenoles/química , Azúcares
14.
Small ; 19(30): e2300620, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37058080

RESUMEN

Electroreduction of nitrite (NO2 - ) to valuable ammonia (NH3 ) offers a sustainable and green approach for NH3 synthesis. Here, a Cu3 P@TiO2 heterostructure is rationally constructed as an active catalyst for selective NO2 - -to-NH3 electroreduction, with rich nanosized Cu3 P anchored on a TiO2 nanoribbon array on Ti plate (Cu3 P@TiO2 /TP). When performed in the 0.1 m NaOH with 0.1 m NaNO2 , the Cu3 P@TiO2 /TP electrode obtains a large NH3 yield of 1583.4 µmol h-1  cm-2 and a high Faradaic efficiency of 97.1%. More importantly, Cu3 P@TiO2 /TP also delivers remarkable long-term stability for 50 h electrolysis. Theoretical calculations indicate that intermediate adsorption/conversion processes on Cu3 P@TiO2 interfaces are synergistically optimized, substantially facilitating the conversion of NO2 - -to-NH3 .

15.
Small ; 19(24): e2300291, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36919558

RESUMEN

Synthesis of green ammonia (NH3 ) via electrolysis of nitric oxide (NO) is extraordinarily sustainable, but multielectron/proton-involved hydrogenation steps as well as low concentrations of NO can lead to poor activities and selectivities of electrocatalysts. Herein, it is reported that oxygen-defective TiO2 nanoarray supported on Ti plate (TiO2- x /TP) behaves as an efficient catalyst for NO reduction to NH3 . In 0.2 m phosphate-buffered electrolyte, such TiO2- x /TP shows competitive electrocatalytic NH3 synthesis activity with a maximum NH3 yield of 1233.2 µg h-1  cm-2 and Faradaic efficiency of 92.5%. Density functional theory calculations further thermodynamically faster NO deoxygenation and protonation processes on TiO2- x (101) compared to perfect TiO2 (101). And the low energy barrier of 0.7 eV on TiO2- x (101) for the potential-determining step further highlights the greatly improved intrinsic activity. In addition, a Zn-NO battery is fabricated with TiO2- x /TP and Zn plate to obtain an NH3 yield of 241.7 µg h-1  cm-2 while providing a peak power density of 0.84 mW cm-2 .

16.
Small ; 19(17): e2208036, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36717274

RESUMEN

Electrochemical nitrate (NO3 - ) reduction reaction (NO3 - RR) is a potential sustainable route for large-scale ambient ammonia (NH3 ) synthesis and regulating the nitrogen cycle. However, as this reaction involves multi-electron transfer steps, it urgently needs efficient electrocatalysts on promoting NH3  selectivity. Herein, a rational design of Co nanoparticles anchored on TiO2  nanobelt array on titanium plate (Co@TiO2 /TP) is presented as a high-efficiency electrocatalyst for NO3 - RR. Density theory calculations demonstrate that the constructed Schottky heterostructures coupling metallic Co with semiconductor TiO2  develop a built-in electric field, which can accelerate the rate determining step and facilitate NO3 - adsorption, ensuring the selective conversion to NH3 . Expectantly, the Co@TiO2 /TP electrocatalyst attains an excellent Faradaic efficiency of 96.7% and a high NH3  yield of 800.0 µmol h-1  cm-2  under neutral solution. More importantly, Co@TiO2 /TP heterostructure catalyst also presents a remarkable stability in 50-h electrolysis test.

17.
Inorg Chem ; 62(1): 25-29, 2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36537850

RESUMEN

Electrochemical nitrate (NO3-) reduction is a potential approach to produce high-value ammonia (NH3) while removing NO3- pollution, but it requires electrocatalysts with high efficiency and selectivity. Herein, we report the development of Fe3O4 nanoparticles decorated TiO2 nanoribbon array on titanium plate (Fe3O4@TiO2/TP) as an efficient electrocatalyst for NO3--to-NH3 conversion. When operated in 0.1 M phosphate-buffered saline and 0.1 M NO3-, such Fe3O4@TiO2/TP achieves a prominent NH3 yield of 12394.3 µg h-1 cm-2 and a high Faradaic efficiency of 88.4%. In addition, it exhibits excellent stability during long-time electrolysis.


Asunto(s)
Nanopartículas , Nanotubos de Carbono , Nitratos , Amoníaco
18.
Microb Biotechnol ; 16(1): 139-147, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36415948

RESUMEN

Aspergillus genus is a key component in fermentation and food processing. However, sterigmatocystin (STE)-a mycotoxin produced by several species of Aspergillus-limits the use of some Aspergillus species (such as Aspergillus versicolor, Aspergillus inflatus, and Aspergillus parasiticus) because of its toxicity and carcinogenicity. Here, we engineered an STE-free Aspergillus versicolor strain based on genome mining techniques. We sequenced and assembled the Aspergillus versicolor D5 genome (34.52 Mb), in which we identified 16 scaffolds and 54 biosynthetic gene clusters (BGCs). We silenced cytochrome P450 coding genes STC17 and STC27 by insertional inactivation. The production of STE in the Δstc17 mutant strain was increased by 282% but no STE was detected in the Δstc27 mutant. Metabolites of Δstc27 mutant exhibited growth-promoting effect on plants. Our study makes significant progress in improving the application of some Aspergillus strains by restricting their production of toxic and carcinogenic compounds.


Asunto(s)
Aspergillus , Esterigmatocistina , Esterigmatocistina/metabolismo , Aspergillus/genética , Aspergillus/metabolismo , Metabolismo Secundario , Fermentación
19.
J Colloid Interface Sci ; 630(Pt A): 714-720, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36274406

RESUMEN

Electrochemical nitrate (NO3-) reduction reaction (NO3RR) possesses two-pronged properties for sustainable ammonia (NH3) synthesis and mitigating NO3- contamination in water. However, the sluggish kinetics for the direct eight-electron NO3--to-NH3 conversion makes a formidable challenge to develop efficient electrocatalysts. Herein, we report a heterostructure of Co3O4 nanosheets decorated TiO2 nanobelt array on titanium plate (Co3O4@TiO2/TP) as an efficient NO3RR electrocatalyst. Both experimental and density theory calculations reveal that the heterostructure of Co3O4@TiO2 establishes a built-in electric field which can optimize the electron migration kinetics, as well as facilitate the adsorption and fixation of NO3- on the electrode surface, ensuring the selectivity to NH3. As expected, the designed Co3O4@TiO2/TP exhibits a remarkable Faradaic efficiency of 93.1 % and a remarkable NH3 yield as high as 875 µmol h-1 cm-2, superior to Co3O4/TP and TiO2/TP. Significantly, it also demonstrates strong electrochemical durability.

20.
J Colloid Interface Sci ; 629(Pt A): 805-812, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36099848

RESUMEN

Direct electrocatalytic reduction of nitrate (NO3-) is an efficient route to simultaneously synthesize ammonia (NH3) and remove NO3- pollutants under ambient conditions, however, it is hindered by the lack of efficient and stable catalysts. Herein, a self-supported spinel-type MnCo2O4 nanowire array is demonstrated for exclusively catalyzing the conversion of NO3- to NH3, achieving a high Faradic efficiency of 97.1% and a large NH3 yield of 0.67 mmol h-1 cm-2. Furthermore, density functional analysis reveals that MnCo2O4 (220) surface has high activity for NO3- reduction with a low energy barrier of 0.46 eV for *NO to *NOH.

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