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1.
Nanoscale ; 16(4): 1733-1741, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38174922

RESUMEN

Two-step photoexcitation overall water splitting based on particulate photocatalysts represents a promising approach for low-cost solar hydrogen production. The performance of an O2-evolution photocatalyst and electron mediator between two photocatalysts crucially influences the construction of an efficient two-step excitation water-splitting system. Bismuth-tantalum oxyhalides are emerging photocatalysts for O2 evolution reactions and can be applied in two-step water-splitting systems. In this study, a highly crystalline Bi4TaO8Cl0.9Br0.1 solid solution with microplatelet morphology was synthesized by the dual flux method. The light absorption intensity and charge transfer efficiency of the Bi4TaO8Cl0.9Br0.1 solid solution were higher than those of Bi4TaO8Cl and Bi4TaO8Br; thus, the sacrificial O2 evolution activity of Bi4TaO8Cl0.9Br0.1 photocatalyst was obviously enhanced. The two-step excitation water splitting with a solid-state electron mediator was successfully constructed using Bi4TaO8Cl0.9Br0.1 as the O2-evolution photocatalyst and Ru/SrTiO3:Rh as the H2-evolution photocatalyst. The CoOx cocatalyst and reduced graphene oxide decorations on the surface of Bi4TaO8Cl0.9Br0.1 promoted the catalytic O2 generation process on Bi4TaO8Cl0.9Br0.1 and electron transfer between CoOx/Bi4TaO8Cl0.9Br0.1 and Ru/SrTiO3:Rh photocatalysts, respectively. As a result, the apparent quantum yield for this overall water-splitting system was 1.26% at 420 nm, which surpassed the present performance of the two-step excitation water-splitting systems consisting of metal oxyhalide photocatalysts. This study demonstrates the validity of high-quality solid-solution photocatalysts with suitable surface modification for efficient solar hydrogen production from water splitting.

2.
Int Immunopharmacol ; 121: 110434, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37315371

RESUMEN

Tyrosine kinase 2 (TYK2) is a member of the Janus kinase (JAK) family, which can regulate the signaling of multiple pro-inflammatory cytokines, including IL12, IL23 and type I interferon (IFNα/ß), and its inhibitors can treat autoimmune diseases caused by the abnormal expression of IL12 and IL23. Interest in TYK2 JH2 inhibitors has increased as a result of safety concerns with JAK inhibitors. This overview introduces TYK2 JH2 inhibitors that are already on the market, including Deucravactinib (BMS-986165), as well as those currently in clinical trials, such as BMS-986202, NDI-034858, and ESK-001.


Asunto(s)
Inhibidores de las Cinasas Janus , TYK2 Quinasa , TYK2 Quinasa/metabolismo , Quinasas Janus/metabolismo , Transducción de Señal , Interleucina-12
3.
Front Public Health ; 11: 990051, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36817889

RESUMEN

Benzene is used as an industrial solvent, which may result in chronic benzene poisoning (CBP). Several studies suggested that CBP was associated with mitochondrial epigenetic regulation. This study aimed to explore the potential relation between CBP and mitochondrial DNA (mtDNA) methylation. This prospective observational study enrolled CBP patients admitted to Shenzhen Prevention and Treatment Center for Occupational Diseases hospital and healthy individuals between 2018 and 2021. The white blood cell (WBC), red blood cell (RBC), hemoglobin (HB), and platelet (PLT) counts and mtDNA methylation levels were measured using blood flow cytometry and targeted bisulfite sequencing, respectively. A total of 90 participants were recruited, including 30 cases of CBP (20 females, mean age 43.0 ± 8.0 years) and 60 healthy individuals (42 females, mean age 43.5 ± 11.5 years). This study detected 168 mitochondrial methylation sites >0 in all study subjects. The mtDNA methylation levels in the CBP cases were lower than the healthy individuals [median ± interquartile-range (IQR), 25th percentile, 75th percentile: (1.140 ± 0.570, 0.965, 1.535)% vs. median ± IQR, 25th percentile, 75th percentile: (1.705 ± 0.205,1.240,2.445)%, P < 0.05]. Additionally, the spearman correlation analysis showed that the mtDNA methylation levels were positively correlated with the counts of circulating leukocytes [WBC (r = 0.048, P = 0.036)] and platelets [PLT (r = 0.129, P < 0.01)]. We provided solid evidence of association between CBP and aberrant mtDNA methylation.


Asunto(s)
Benceno , Epigénesis Genética , Femenino , Humanos , Adulto , Persona de Mediana Edad , Mitocondrias , ADN Mitocondrial , Metilación de ADN
4.
Chemistry ; 28(68): e202202044, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36082681

RESUMEN

Cubic-like CaTaO2 N photocatalysts with high crystallinity and uniform particle size were successfully prepared by the flux-assisted nitridation method. The growth of CaTaO2 N single crystals under different synthesis conditions was systematically investigated to understand the effects of the crystallinity and optical property on photocatalytic performance of CO2 reduction. Moreover, the modification of CaTaO2 N single crystals with core-shell Ni-Ag bicomponent cocatalyst by two-step decoration process gave a 2.4 times higher amount of CO evolution than the deposition of sole Ag cocatalyst, because of the synergistic effects of bicomponent cocatalyst on the interfacial electron transfer and surface catalytic process. This study provides a valuable way to construct high-crystalline photocatalysts with effective bicomponent cocatalyst for visible-light-driven CO2 reduction with H2 O.

5.
Chem Commun (Camb) ; 57(42): 5167-5170, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-33903867

RESUMEN

Aqueous glycerol was used in this study as a liquid-phase hydrogen source for the hydrogenation of CO2. It was found that hydrogen could be efficiently evolved from aqueous glycerol upon highly dispersed Ru on layered double hydroxide (LDH), inducing the transformation of CO2 into formaldehyde under base-free conditions at low temperature.

6.
Chem Asian J ; 16(8): 949-958, 2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33646609

RESUMEN

CO2 hydrogenation for syngas can alleviate the pressure of un-controlled emissions of CO2 and bring enormous economic benefits. Advantageous Ni-catalysts have good CO2 hydrogenation activity and high CO selectivity merely over 700 °C. Herein, we introduced Cu into Ni catalysts, which were evaluated by H2 -TPR, XRD, BET, in-situ XPS and CO2 -TPD, and their CO2 hydrogenation activity and CO selectivity were significantly affected by the Ni/Cu ratios, which was rationalized by the synergistic effect of bimetallic catalysts. In addition, the reduction temperatures of studied catalysts apparently affected the CO2 hydrogenation, which were caused by the number and dispersion of the active species. It's found that the Ni1 Cu1 -400 had good stability, high CO selectivity (up to 90%), and fast formation rate (1.81×10-5  mol/gcat /s) at 400 °C, which demonstrated a good potential as a superior catalyst for reverse water-gas shift (RWGS) reaction.

7.
J Hazard Mater ; 404(Pt A): 124108, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33032090

RESUMEN

Ag-modified vanadium silicate (EVS-Ag) has been regarded as a superior sorbent for elemental mercury (Hg0) capture from coal-fired flue gas. However, the atomic-level reaction mechanism which determines Hg0 adsorption capacity of EVS-Ag sorbent remains elusive. Reaction mechanism and active sites of Hg0 adsorption over EVS-Ag sorbent were studied using density functional theory (DFT) calculations systematically. DFT calculation results indicate that silver exchange shows little effects on the geometric structure of EVS-10 sorbent. Hg0 adsorption on EVS-10 and EVS-Ag surfaces is controlled by the physisorption and chemisorption mechanisms, respectively. Ag2 cluster is determined to be the most active site of Hg0 adsorption over Ag-modified EVS sorbent. The adsorption energy of Hg0 on Ag2 cluster is -51.93 kJ/mol. The orbital hybridization and electron sharing between Ag and Hg atoms are responsible for the strong interaction between EVS-Ag surface and Hg0. HgO prefers to adsorb on Ag2 cluster of EVS-Ag sorbent, and yields an energy release of 306.21 kJ/mol. HgO desorption from EVS-Ag sorbent surface needs a higher external energy, and occurs at the relatively higher temperatures. O2 molecule promotes Hg0 adsorption over EVS-Ag sorbent. HgO species can be easily formed during Hg0 adsorption over EVS-Ag sorbent in the presence of O2.

8.
Chem Commun (Camb) ; 55(96): 14410-14413, 2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31657389

RESUMEN

Strong metal-support interaction (SMSI) over Ru/CaAlOx was constructed by utilizing the surface structural reconstruction of Ca-Al layered double hydroxides (LDHs) in aqueous solution and their subsequent hydroxide-to-oxide transformations. Ru nanoparticles were found to uniformly embed with CaAlOx. The electronic interactions and changes in CO adsorption behavior confirmed the SMSI state between Ru and CaAlOx. Owing to SMSI, the as-prepared Ru/CaAlOx showed improved catalytic activity in the decomposition of ammonia, especially at a relatively low temperature.

9.
Chem Commun (Camb) ; 53(51): 6937-6940, 2017 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-28612887

RESUMEN

Pt/SiO2 reduced at 1073 K exhibited a high catalytic activity in propane dehydrogenation, primarily attributed to the electronic modification of Pt nanoparticles by a strong metal-support interaction (SMSI) effect. The SMSI was observed in the Pt/SiO2 system following direct reduction in H2 (>773 K), and was found to increase with increasing reduction temperature.

10.
J Environ Sci (China) ; 22(9): 1447-54, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21174978

RESUMEN

The catalysts of iron-doped Mn-Ce/TiO2 (Fe-Mn-Ce/TiO2) prepared by sol-gel method were investigated for low temperature selective catalytic reduction (SCR) of NO with NH3. It was found that the NO conversion over Fe-Mn-Ce/TiO2 was obviously improved after iron doping compared with that over Mn-Ce/TiO2. Fe-Mn-Ce/TiO2 with the molar ratio of Fe/Ti = 0.1 exhibited the highest activity. The results showed that 96.8% NO conversion was obtained over Fe (0.1)-Mn-Ce/TiO2 at 180 degrees C at a space velocity of 50,000 hr(-1). Fe-Mn-Ce/TiO2 exhibited much higher resistance to H2O and SO2 than that of Mn-Ce/TiO2. The properties of the catalysts were characterized using X-ray diffraction (XRD), N2 adsorption, temperature programmed desorption (NH3-TPD and NOx-TPD), and Xray photoelectron spectroscopy (XPS) techniques. BET, NH3-TPD and NOx-TPD results showed that the specific surface area and NH3 and NOx adsorption capacity of the catalysts increased with iron doping. It was known from XPS analysis that iron valence state on the surface of the catalysts were in Fe3+ state. The doping of iron enhanced the dispersion and oxidation state of Mn and Ce on the surface of the catalysts. The oxygen concentrations on the surface of the catalysts were found to increase after iron doping. Fe-Mn-Ce/TiO2 represented a promising catalyst for low temperature SCR of NO with NH3 in the presence of H2O and SO2.


Asunto(s)
Amoníaco/química , Cesio/química , Hierro/química , Manganeso/química , Óxidos de Nitrógeno/química , Titanio/química , Catálisis , Oxidación-Reducción , Temperatura
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