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1.
Phys Chem Chem Phys ; 26(3): 1625-1629, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38170902

RESUMEN

Photocorrosion is the most ticklish problem of cuprous oxide (Cu2O), and it is widely assumed that the deactivation of Cu2O photocathodes in solar water splitting is caused by spontaneous oxidation-reduction (REDOX) reactions. However, this work shows that 〈100〉-oriented Cu2O photocathodes undergo a non-REDOX hydration deactivation mechanism. Briefly, water molecules are embedded in the Cu2O crystals at low potential under illumination and produce amorphous CuOH, which can be dehydrated at high potential to heal the Cu-O-Cu bonds and regenerate foamed Cu2O films with a three-dimensional skeleton structure. This study provides a new insight towards the protection and application of Cu2O photocathodes.

2.
Nano Lett ; 24(4): 1351-1359, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38251855

RESUMEN

The anomalous Hall effect (AHE) is one of the most fascinating transport properties in condensed matter physics. However, the AHE magnitude, which mainly depends on net spin polarization and band topology, is generally small in oxides and thus limits potential applications. Here, we demonstrate a giant enhancement of AHE in a LaCoO3-induced 5d itinerant ferromagnet SrIrO3 by hydrogenation. The anomalous Hall resistivity and anomalous Hall angle, which are two of the most critical parameters in AHE-based devices, are found to increase to 62.2 µΩ·cm and 3%, respectively, showing an unprecedentedly large enhancement ratio of ∼10000%. Theoretical analysis suggests the key roles of Berry curvature in enhancing AHE. Furthermore, the hydrogenation concomitantly induces the significant elevation of Curie temperature from 75 to 160 K and 40-fold reinforcement of coercivity. Such giant regulation and very large AHE magnitude observed in SrIrO3 could pave the path for 5d oxide devices.

3.
Front Microbiol ; 14: 1239218, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37720154

RESUMEN

In this study, the effects of different enzymes (lysozyme, α-amylase and neutral protease) on sludge hydrolysis efficiency and microbial community in sequencing batch reactor (SBR) were introduced. The results showed that the hydrolysis efficiencies of the three enzymes were 48.5, 22.5 and 31%, respectively, compared with the accumulated sludge discharge of the blank control group. However, it has varying degrees of impact on the effluent quality, and the denitrification and phosphorus removal effect of the system deteriorates. The lysozyme that achieves the optimal sludge hydrolysis effect of 48.5% has the greatest impact on the chemical oxygen demand (COD), total nitrogen (TN), and nitrate nitrogen (NO3--N) of the effluent. The sludge samples of the control group and the groups supplemented with different enzyme preparations were subjected to high-throughput sequencing. It was found that the number of OTUs (Operational Taxonomic Units) of the samples was lysozyme > α-amylase > blank control > neutral protease. Moreover, the abundance grade curve of the sludge samples supplemented with lysozyme and α-amylase was smoother, and the community richness and diversity were improved by lysozyme and α-amylase. The species diversity of the sludge supplemented with lysozyme and neutral protease was great, and the community succession was obvious. The introduction of enzymes did not change the main microbial communities of the sludge, which were mainly Proteobacteria, Actinobacteria and Bacteroidetes. The effects of three enzyme preparations on sludge reduction and microbial diversity during pilot operation were analyzed, the gap in microbial research was filled, which provided theoretical value for the practical operation of enzymatic sludge reduction.

4.
J Phys Chem Lett ; 13(51): 11946-11954, 2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36534070

RESUMEN

The weakly correlated nature of 5d oxide SrIrO3 determines its rare ferromagnetism, and the control of its magnetic order is even less studied. Tailoring structure distortion is currently a main route to tune the magnetic order of 5d iridates, but only for the spatially confined insulating counterparts. Here, we have realized ferromagnetic order in metallic SrIrO3 by construction of SrIrO3/ferromagnetic-insulator (LaCoO3) superlattices, which reveal a giant coercivity of ∼10 T and saturation field of ∼25 T with strong perpendicular magnetic anisotropy. The Curie temperature of SrIrO3 can be controlled by engineering interface charge transfer, which is confirmed by Hall effect measurements collaborating with EELS and XAS. Besides, the noncoplanar spin texture is captured, which is caused by interfacial Dzyaloshinskii-Moriya interactions as well. These results indicate controllable itinerant ferromagnetism and an emergent topological magnetic state in strong spin-orbit coupled semimetal SrIrO3, showing great potential to develop efficient spintronic devices.

5.
Fitoterapia ; 149: 104823, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33387642

RESUMEN

Four new cyclohexene derivatives cladoscyclitols A-D (1-4) and one new ribofuranose phenol derivative 4-O-α-D-ribofuranose-2-pentyl-3-phemethylol (5) were obtained from the EtOAC extract of the mangrove-derived endophytic fungus Cladosporium sp. JJM22. The structures were elucidated by extensive NMR and MS analysis, while the absolute configurations of the stereogenic carbons were established based on quantum-chemical electronic circular dichroism calculations or comparison of the optical rotations with those of related compounds. Compounds 2 and 5 displayed potent inhibitory activity against α-glucosidase with the IC50 values of 2.95 and 2.05 µM, respectively.


Asunto(s)
Cladosporium/química , Ciclohexenos/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , Rhizophoraceae/microbiología , China , Ciclohexenos/aislamiento & purificación , Endófitos/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular
6.
RSC Adv ; 11(60): 37830-37841, 2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-35498113

RESUMEN

A tertiary component with higher molecular weight of epoxy terminated polysiloxane (DMS-E11) was incorporated into the diglycidyl ether of bisphenol-A (DGEBA)/thermoplastic polyetherimide (PEI) blends. In this ternary DGEBA/PEI/DMS-E11 system, 25 or 30 wt% PEI and no more than 20 wt% DMS-E11 were used to ensure the formation of a continuous PEI-rich phase via reaction induced phase separation for optimum mechanical properties of blends. The results of morphology monitoring by OM and TRLS indicated that the addition of DMS-E11 could accelerate phase separation of DGEBA/PEI. Obvious differences were observed by SEM/EDS in the final morphologies of the blends. DMS-E11 localized in the PEI-rich phase continuously while it separated with DGEBA into spherical particles in the DGEBA-rich phase. DMA measurements found that the storage modulus and T g decreased with DMS-E11 content but were compensated partly by the presence of PEI. The results of tensile tests confirmed the synergistic strengthening for epoxy resin from PEI and DMS-E11.

7.
Nat Prod Res ; 33(1): 34-40, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29388439

RESUMEN

Two new compounds (1 and 2), together with six known compounds (3-8), were obtained from the Cladosporium sp. JJM22, an endophytic fungus isolated from the stem bark of the mangrove plant Ceriops tagal collected in South China Sea. Their structures were elucidated on the basis of detailed spectroscopic analysis. The absolute configurations of 1 and 2 were confirmed by the comparison of optical rotation and the CD data with those of known compounds. The inhibitory activities of the isolated compounds against six terrestrial pathogenic bacteria and human cervical carcinoma Hela cell line were evaluated. Compound 3 exhibited a broad spectrum of antibacterial activities.


Asunto(s)
Antibacterianos/aislamiento & purificación , Cladosporium/química , Hongos/química , Rhizophoraceae/microbiología , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , China , Células HeLa/efectos de los fármacos , Humanos , Estructura Molecular , Análisis Espectral
8.
Nat Prod Res ; 31(9): 1042-1046, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27931121

RESUMEN

A new phenolic glycoside dendroside (1), together with seven known compounds (2-8) were isolated from the stems of Dendrobium nobile. The structures of these compounds were elucidated using comprehensive spectroscopic methods. The inhibitory activities of all compounds against three cancer cell lines HeLa, MCF-7 and A549 were evaluated.


Asunto(s)
Dendrobium/química , Glicósidos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Glicósidos/química , Glicósidos/farmacología , Humanos , Fenoles/análisis , Tallos de la Planta/química
9.
Fitoterapia ; 115: 96-100, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27720924

RESUMEN

Five new lactone derivatives decumbic acids A and B (1 and 2), (-)-decumbic acid (3a), (-)- and (+)-dendrolactone (4a and 4b) together with four known compounds (3b and 5-7) were isolated from the stems of Dendrobium nobile. Their structures were elucidated using comprehensive spectroscopic methods. Compounds 3a and 3b, 4a and 4b were isolated as two pair of enantiomers by chiral HPLC. The absolute configurations of 1, 2, 3a, 4a and 4b were determined by optical rotation and X-ray crystallographic analysis. The inhibitory activities of all compounds against nine phytopathogenic fungi and three cancer cell lines were evaluated.


Asunto(s)
Dendrobium/química , Lactonas/química , Tallos de la Planta/química , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Hongos/efectos de los fármacos , Humanos , Lactonas/aislamiento & purificación , Estructura Molecular
10.
ScientificWorldJournal ; 2014: 645341, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25258729

RESUMEN

Based on linguistic term sets and hesitant fuzzy sets, the concept of hesitant fuzzy linguistic sets was introduced. The focus of this paper is the multicriteria decision-making (MCDM) problems in which the criteria are in different priority levels and the criteria values take the form of hesitant fuzzy linguistic numbers (HFLNs). A new approach to solving these problems is proposed, which is based on the generalized prioritized aggregation operator of HFLNs. Firstly, the new operations and comparison method for HFLNs are provided and some linguistic scale functions are applied. Subsequently, two prioritized aggregation operators and a generalized prioritized aggregation operator of HFLNs are developed and applied to MCDM problems. Finally, an illustrative example is given to illustrate the effectiveness and feasibility of the proposed method, which are then compared to the existing approach.


Asunto(s)
Algoritmos , Toma de Decisiones , Lógica Difusa , Modelos Teóricos , Técnicas de Apoyo para la Decisión , Estudios de Factibilidad , Lingüística , Reproducibilidad de los Resultados
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