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1.
Dalton Trans ; 53(10): 4737-4752, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38363114

RESUMEN

With ZIF-67 as the precursor, oxygen vacancy-rich Co3O4 nanoparticles were derived and anchored on the surface of 2D polyimide (PI) to construct a Z-scheme hybrid heterojunction (20ZP) through a simultaneous solvothermal in situ crystallization and polymerization strategy. XRD, XPS and EPR confirmed that both Co(III) and oxygen vacancies are formed during the low temperature conversion of ZIF-67 to Co3O4 nanoparticles that in turn accelerate the polymerization of PI. Synchronous crystallization makes the interfacial architecture intermetal and compact, inducing a strong interfacial electronic interaction between Co3O4 nanoparticles and PI. UV-vis DRS spectra and transient photocurrent response demonstrate that the incorporation of Co3O4 on polyimide not only extends the light absorption in the visible range, but also enhances the charge transfer rate. EIS, TRPL techniques and DFT calculations have confirmed that the photoinduced interfacial charge transfer pathway of this hybrid heterojunction characterized the Z-scheme in which the photoinduced electrons transfer from the conduction band of Co3O4 to the valence band of PI, significantly inhibiting the recombination of electrons and holes within PI. More importantly, the oxygen vacancies located below the conductor band of Co3O4 can deepen the band bending, improve the charge separation efficiency and accelerate electron transfer between Co3O4 and PI. This Z-scheme hybrid heterojunction structure can not only maintain the high reducing capacity of photoinduced electrons on the conductor band of PI, but also enhance the oxidative capacity of the heterojunction composite material, thus promoting the overall progress of the photocatalytic hydrogen release reaction.

2.
Dalton Trans ; 52(29): 10013-10022, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37403763

RESUMEN

The aggravating extreme climate changes and environmental pollution problems have stimulated the exploration of green alternatives to conventional fossil fuels and green environmental treatments. Photocatalysis is recognized as an outstanding green tool for solving the energy crisis and environmental rehabilitation issues. Restricted by the high cost of precious metals, researchers expect to obtain low-cost, efficient and stable photocatalysts. Herein, CdS materials were derived through MOFs and subsequently combined with CoO to form CdS/CoO heterojunctions. The catalytic ability was evaluated by the photocatalytic degradation of tetracycline hydrochloride (TC) and the photocatalytic production of hydrogen. With the integration of CoO, in terms of TC degradation, CdS/CoO heterojunctions can degrade over 90% of TC within 1 hour. In terms of hydrogen production, compared to CdS alone, the hydrogen production efficiency of the CdS/CoO heterojunction increased by 1.7 times. The initial analysis of the reasons for the enhancement of photocatalytic efficiency was conducted by TEM, XPS and other characterization means. Density functional theory (DFT) calculations verified the existence of a built-in electric field in the CdS/CoO heterojunction, which was the essential reason for the improved catalytic performance, and finally, the presence of ˙O2- and ˙OH in the photocatalytic system was demonstrated by the ESR technique. Based on the carrier separation/transfer pathway in the heterojunction, a simple and novel S-type heterojunction scheme was proposed.

3.
Front Pharmacol ; 13: 958022, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36176437

RESUMEN

It is worth noting that neuroinflammation is well recognized as a symptom of neurodegenerative diseases (NDs). The regulation of neuroinflammation becomes an attractive focus for innovative ND treatment technologies. There is evidence that IL-22 is associated with the development and progression of a wide assortment of NDs. For example, IL-22 can activate glial cells, causing them to generate pro-inflammatory cytokines and encourage lymphocyte infiltration in the brain. IL-22 mRNA is highly expressed in Alzheimer's disease (AD) patients, and a high expression of IL-22 has also been detected in the brains of patients with other NDs. We examine the role of IL-22 in the development and treatment of NDs in this review, and we believe that IL-22 has therapeutic potential in these diseases.

4.
Dalton Trans ; 51(39): 15080-15088, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36124616

RESUMEN

Constructing a suitable heterojunction structure while maintaining a tight interface to promote the separation of photogenerated electrons is of great significance for improving the photocatalytic activity. In this paper, a new PANI/NH2-MIL-101(Fe) II-scheme heterojunction was prepared by a hydrothermal method. PANI with a porous structure was firstly obtained by the template method, and then PANI fragments were loaded on the surface of NH2-MIL-101(Fe) crystals under hydrothermal conditions to obtain a PANI/NH2-MIL-101(Fe) photocatalyst. The photocatalytic degradation of TC under simulated sunlight can reach 90% within an hour, and the maximum hydrogen evolution rate is 7040 µmol g-1 h-1 under visible light. The enhanced catalytic performance of PANI/NH2-MIL-101(Fe) was attributed to the appropriate matching of the VB and CB of PANI and NH2-MIL-101(Fe), and secondly, the coordination bonds formed between PANI and NH2-MIL-101(Fe) provided a channel for charge separation and transfer. Finally, a possible mechanism of the photocatalytic system was proposed through a free radical capture experiment and characterization analysis. More importantly, the experiment proved that the heterojunction formed by PANI and NH2-MIL-101(Fe) can achieve the effect of complementing each other, which provides a feasible idea and method for the design of efficient heterojunction photocatalysts.

5.
Zhong Yao Cai ; 30(8): 1013-6, 2007 Aug.
Artículo en Chino | MEDLINE | ID: mdl-18074856

RESUMEN

OBJECTIVE: To Study the technologic conditions of purifying total Rosa laevigata by AB-8 pocket. METHODS: Extracting flavonoids from Rosa laevigata with 70% alcohol, the thick flavonoid powder were obtained and the content of pure flavonoids in it could be determinated using spectrophotometry. Taking the adsorption of the AB-8 pocket to Rosa flavonoids as the research object, the factors that affected the AB-8 resin static absorption and desorption were studied preliminarily. RESULTS: The result showed that the effect was perfect when the flavononid concentration in the liquid was 0.3 mg/ml, the loading amount was 120 mg with the adsorption-power 1 ml/ min; And the volume of 70% alcohol was eluant 5 BV with desorption-power 1 ml/min. The pure flavonoid content in thick flavonoid powder was 25.2% and it reached 42.2% after being purified by the AB-8 pocket adsorption resin. CONCLUSION: It proved AB-8 pocket adsorption resin have a better effect on purification of the flavononids of Rosa laevigata.


Asunto(s)
Cromatografía/métodos , Flavonoides/aislamiento & purificación , Resinas Sintéticas/química , Rosales/química , Adsorción , Cromatografía/instrumentación , Etanol , Flavonoides/análisis , Frutas/química , Plantas Medicinales/química , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta , Tecnología Farmacéutica/métodos
6.
Immunology ; 115(2): 189-96, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15885124

RESUMEN

The CD3 antigen is a surface structure associated with the T-cell receptor (TCR) to form a complex involved in antigen recognition and signal transduction. Reports on the structures of the CD3 molecules associated with alphabeta- and gammadelta-TCR have been contradictory. To investigate this issue, we raised a panel of monoclonal antibodies (mAb) against purified porcine CD3 molecules. Unlike the conventional anti-CD3, these mAb reacted specifically with peripheral gammadelta-T cells, but not with alphabeta-T cells. Immunoprecipitation showed that the antibody recognized a subset of CD3 molecules that were associated with gammadelta-TCR. Also unlike the conventional anti-CD3, these mAb, though directed at two different epitope groups, failed to induce antigenic modulation, T-cell proliferation and CD3-redirected cytotoxicity. Taken together, these results suggest that there are differences in the antigenicity, signal transduction potentials and probably structural differences between the CD3 molecules expressed at the surface of alphabeta- and gammadelta-T cells.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Complejo CD3/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/análisis , Porcinos/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Complejo CD3/metabolismo , Proliferación Celular , Femenino , Inmunofenotipificación , Activación de Linfocitos/inmunología , Masculino , Transducción de Señal/inmunología
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