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1.
Nat Commun ; 15(1): 5495, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38944644

RESUMEN

Dry reforming of methane (DRM) is a highly endothermic process, with its development hindered by the harsh thermocatalytic conditions required. We propose an innovative DRM approach utilizing a 16 W pulsed laser in combination with a cost-effective Mo2C catalyst, enabling DRM under milder conditions. The pulsed laser serves a dual function by inducing localized high temperatures and generating *CH plasma on the Mo2C surface. This activates CH4 and CO2, significantly accelerating the DRM reaction. Notably, the laser directly generates *CH plasma from CH4 through thermionic emission and cascade ionization, bypassing the traditional step-by-step dehydrogenation process and eliminating the rate-limiting step of methane cracking. This method maintains a carbon-oxygen balanced environment, thus preventing the deactivation of the Mo2C catalyst due to CO2 oxidation. The laser-catalytic DRM achieves high yields of H2 (14300.8 mmol h-1 g-1) and CO (14949.9 mmol h-1 g-1) with satisfactory energy efficiency (0.98 mmol kJ-1), providing a promising alternative for high-energy-consuming catalytic systems.

2.
Adv Mater ; 36(5): e2305375, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37930270

RESUMEN

Maximizing atom-utilization efficiency and high current stability are crucial for the platinum (Pt)-based electrocatalysts for hydrogen evolution reaction (HER). Herein, the Pt single-atom anchored molybdenum (Mo) foil (Pt-SA/Mo-L) as a single-atom alloy electrode is synthesized by the laser ablation strategy. The local thermal effect with fast rising-cooling rate of laser can achieve the single-atom distribution of the precious metals (e.g., Pt, Rh, Ir, and Ru) onto the Mo foil. The synthesized self-standing Pt-SA/Mo-L electrode exhibits splendid catalytic activity (31 mV at 10 mA cm-2 ) and high-current-density stability (≈850 mA cm-2 for 50 h) for HER in acidic media. The strong coordination of Pt-Mo bonding in Pt-SA/Mo-L is critical for the efficient and stable HER. In addition, the ultralow electrolytic voltage of 0.598 V to afford the current density of 50 mA cm-2 is realized by utilization of the anodic molybdenum oxidation instead of the oxygen evolution reaction (OER). Here a universal synthetic strategy of single-atom alloys (PtMo, RhMo, IrMo, and RuMo) as self-standing electrodes is provided for ultralow voltage and membrane-free hydrogen production.

3.
Hematology ; 28(1): 2227494, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37343172

RESUMEN

BACKGROUND: Galectin (Gal) is considered a promising immune checkpoint molecule. More and more studies have shown that high expression levels of galectins in hematologic cancer are positively correlated with poor clinical prognosis. However, the exact prognostic significance of galectins remains unclear. METHODS: PubMed, Embase, Web of Science, and Cochrane Library were searched for studies addressing the correlation of galectin expression levels with prognosis of hematologic cancers. Stata software was used to estimate hazard ratios (HR) and 95% confidence intervals (CI). RESULT: Hematologic cancer patients with high galectin expression levels showed poor overall survival (OS, HR = 2.43, 95% CI: 1.95, 3.04), disease-free survival (DFS, HR = 3.29, 95% CI: 1.61, 6.71), and event-free survival (EFS, HR = 2.20, 95% CI: 1.47, 3.29) outcomes. Subgroup analysis revealed that high expression levels of galectins pointed to relatively poor OS in MDS (HR = 5.44, 95% CI: 2.09, 14.18), as compared to AML, CHL and CLL. No correlation was found between galectins and OS in NHL and MM. Among the three galectins, Gal-9 (HR = 3.60, 95% CI: 2.03, 6.38) showed higher correlation with poor prognosis than Gal-1 and Gal-3. In addition, use of peripheral blood (HR = 2.96, 95% CI: 2.07, 4.22) samples and qRT-PCR (HR = 2.80, 95% CI: 1.96, 4.01) method for galectin detection were shown to improve its prognostic correlation in hematologic cancers. CONCLUSION: Meta-analysis revealed high expression of galectins was associated with poor prognosis in hematologic cancer patients and galectins can be considered a promising prognostic predictive marker.


Asunto(s)
Galectinas , Neoplasias Hematológicas , Humanos , Galectinas/metabolismo , Pronóstico , Modelos de Riesgos Proporcionales , Supervivencia sin Enfermedad , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/genética
4.
PLoS One ; 17(3): e0264980, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35324940

RESUMEN

Under the context of global warming, compound dry and hot events (CDHEs) will increase and bring serious losses to society and the economy. The projection of CDHEs is of great significance for policy-making and risk assessment. In this paper, two large ensemble simulations, CanESM2-LE and CESM-LE, are used to estimate the risk of extreme CDHEs under different warming scenarios in China. First, the biases of the model in the simulation of the temperature and precipitation over the China region are corrected, and the index of CDHEs is established based on a copula function. The results show that extreme CDHEs will occur more often in China with the increase in global warming and the more severe extreme CDHEs are, the greater the risk will be in the future with higher uncertainties. Events that would be attained once every 50 and 100 years in the current climate from CESM-LE (CAanESM2-LE) will be 1.2/1.6 (1.1/1.5) times and 1.3/2.3 (1.5/2.0) times more likely to occur in a 1.5°C/2.0°C warmer climate, respectively. Northwestern China will experience the greatest increase in the risk of extreme CDHEs. Extreme CDHEs expected once every 100 years in the current period over NW China are expected to occur approximately every 5 and 4 years under a 4.0°C warmer world in CanESM2-LE and CESM-LE, respectively.


Asunto(s)
Cambio Climático , Clima , China/epidemiología , Calentamiento Global , Calor
5.
Dalton Trans ; 49(40): 13993-13998, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-33078802

RESUMEN

One bonded- and one discreted-Lindqvist hexatungstate-based copper hybrids (Cu-POMs) ([Cu2(O)OH(phen)2]2[W6O19]·6H2O (1) and [Cu2(phen)4Cl] [HW6O19]·2H2O (2) (phen = 1,10-phenanthroline)) were controllably synthesized and routinely characterized. Cu-POMs 1-2 consisted of identical [W6O19] unit and similar copper-phen complexes, the two units are bonded via four Cu-O chemical bonds in compound 1; however, compound 2 is discreted and stabilized by intermolecular electrostatic interactions. Importantly, these Cu-POMs catalysts were first applied in the novel reaction for the preparation of 2-phenylquinoxalines via the one-pot coupling and oxidation reactions of 2-haloanilines with vinyl azides or 3-phenyl-2H-azirines under mild conditions, and Cu-POMs 1 showed higher catalytic performance in good yields (79-84%). The reactions exhibit some functional group tolerance and allow for the preparation of a number of 2-phenylquinoxalines.

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