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1.
ACS Appl Mater Interfaces ; 13(42): 50350-50357, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34647456

RESUMO

The development of new high-density memories that can work in harsh environments such as high temperature and humidity will be significant for some special occasions such as oil and geothermal industries. Herein, a facial strategy for implementing a ternary memory device with high working temperature/humidity was executed. In detail, an asymmetric aggregation-induced-emission active molecule (azobenzol-decorated tetraphenylethylene, i.e., TPE-Azo) was embedded into flexible poly(ethylene-alt-maleic anhydride) (PEM) to prepare a TPE-Azo@PEM composite, which served as an active layer to fabricate the FTO/TPE-Azo@PEM/Ag device. This device can demonstrate excellent ternary memory performances with a current ratio of 1:104.2:101.6 for "OFF", "ON1", and "ON2" states. Specially, it can exhibit good environmental endurance at high working temperature (350 °C) and humidity (RH = 90%). The ternary memory mechanism can be explained as the combination of aggregation-induced current/conductance and conformational change-induced charge transfer in the TPE-Azo molecule, which was verified by Kelvin probe force microscopy, UV-vis spectra, X-ray diffraction, and single-crystal structural analysis. This strategy can be used as a universal method for the construction of high-density multilevel memristors with good environmental tolerance.

2.
Huan Jing Ke Xue ; 42(10): 5030-5036, 2021 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-34581147

RESUMO

The aim of this study was to investigate the effects of feedstock material and pyrolysis temperature on the content and spectral properties of dissolved organic matter(DOM) in biochars. Biochars were produced from the pyrolysis of rice straw and Cunninghamia lanceolata litter at three temperatures(350, 500, and 650℃). The results showed that the pH values of the two biochars with pyrolysis temperature increases were improved from 8.10 and 6.56 to 10.53 and 8.23, respectively. The pyrolysis temperature had no significant effect on the total C content of biochar, but the feedstock material and their interaction had significant effects on the total C content of the biochar(P<0.05). The dissolved organic carbon(DOC) content of the two types of biochar first decreased and then increased with increasing pyrolysis temperature, and the content of DOC of the biochar derived from rice straw was significantly higher than that from Cunninghamia lanceolata litter under the same temperature(P<0.05). The feedstock material had no significant effect on the SUVA254 value of DOM, but temperature and its interactive effect with the feedstock material had a significant effect on the SUVA254 values(P<0.05). Maximum DOC SUVA254 values occurred at 500℃ in the two types of biochar, indicating the highest degree of aromatization. Three-dimensional fluorescence spectra showed that the DOM components of the two types of biochar were dominated by fulvic acid-like and humic acid-like material, which had different responses to pyrolysis temperature. FTIR spectra suggested that the DOM of the biochars had absorption peaks at similar positions, in five regions, and the stretching vibration of aliphatic C-H gradually weakened with an increase in pyrolysis temperature. Therefore, the biochars produced at higher pyrolysis temperatures(500℃ and 650℃) had lower DOC contents but a higher aromatization degree and humification degree, and were more stable, compared to the biochars produced at a lower pyrolysis temperature(350℃).


Assuntos
Carvão Vegetal , Pirólise , Substâncias Húmicas/análise , Temperatura
3.
Front Vet Sci ; 8: 819293, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071399

RESUMO

Tumorigenesis is associated with metabolic abnormalities and genomic instability. Microsatellite mutations, including microsatellite instability (MSI) and loss of heterozygosity (LOH), are associated with the functional impairment of some tumor-related genes. To investigate the role of MSI and LOH in sporadic breast tumors in canines, 22 tumors DNA samples and their adjacent normal tissues were evaluated using polyacrylamide gel electrophoresis and silver staining for 58 microsatellites. Quantitative real-time polymerase chain reaction, promoter methylation analysis and immunohistochemical staining were used to quantify gene expression. The results revealed that a total of 14 tumors (6 benign tumors and 8 breast cancers) exhibited instability as MSI-Low tumors. Most of the microsatellite loci possessed a single occurrence of mutations. The maximum number of MSI mutations on loci was observed in tumors with a lower degree of differentiation. Among the unstable markers, FH2060 (4/22), ABCC9tetra (4/22) and SCN11A (6/22) were high-frequency mutation sites, whereas FH2060 was a high-frequency LOH site (4/22). The ABCC9tetra locus was mutated only in cancerous tissue, although it was excluded by transcription. The corresponding genes and proteins were significantly downregulated in malignant tissues, particularly in tumors with MSI. Furthermore, the promoter methylation results of the adenosine triphosphate binding cassette subfamily C member 9 (ABCC9) showed that there was a high level of methylation in breast tissues, but only one case showed a significant elevation compared with the control. In conclusion, MSI-Low or MSI-Stable is characteristic of most sporadic mammary tumors. Genes associated with tumorigenesis are more likely to develop MSI. ABCC9 protein and transcription abnormalities may be associated with ABCC9tetra instability.

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