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1.
Crit Rev Anal Chem ; 52(3): 504-518, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-32845172

RESUMEN

As growing concerns on green, cost-effective, and time-saving chemistry analysis methods, deep eutectic solvents (DESs) are considered to be promising green alternatives to conventional solvents in dispersive liquid-liquid microextraction (DLLME) of trace level chemical contaminants in food and water, due to their biodegradability, low cost, and simple preparation. In the past few years, numerous innovative researches have focused on preconcentration of trace level chemical contaminants using DESs as extractant. In this context, this review aims to summarize the updated state-of-the-art effort dedicated to preconcentration of trace level chemical contaminants in food and water sample using DESs as extractants in DLLME. Furthermore, the major impact factors affecting the preconcentration efficiency and process mechanisms are thoroughly analyzed and discussed. Finally, prospects and challenges in application of DESs as solvents in DLLME to enrich trace level chemical contaminants are extensively elucidated and critically reviewed.


Asunto(s)
Microextracción en Fase Líquida , Contaminantes Químicos del Agua , Disolventes Eutécticos Profundos , Microextracción en Fase Líquida/métodos , Solventes , Agua , Contaminantes Químicos del Agua/análisis
2.
ACS Appl Mater Interfaces ; 13(48): 57100-57106, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34843222

RESUMEN

Acid-catalyzed conversion of biomass into bio-based platform chemicals such as levulinic acid and 5-hydroxymethylfurfural is an important route in biorefineries, which has attracted much attention in recent years. Such a route however unavoidably yields massive recalcitrant byproducts called humins, which are now broadly considered as waste and are limited to combustion, causing unfavorable energy and environmental processes. Therefore, the development of a value-added utilization approach for such humin byproducts is crucial for making the biorefineries economical and environmentally viable. In this work, we present a starting point for valorization of humins via the preparation of carbon-based iron oxide nanocomposites of FeO@graphite@C by using the humins as carbon resources and material templates via a facile synthesis strategy. The as-prepared catalyst is capable of promoting the reverse water-gas shift reaction and reaching a high CO2 conversion ratio with excellent CO selectivity (> 99%) at 500-700 °C, enabling an efficient utilization of waste CO2. The unique graphite-capsuled FeO structure of FeO@graphite@C was found to be the origin of its excellent catalytic activity toward CO2 reduction into CO, which shifts electrons from the graphite layer to FeO, reconstructing the Fe electron structure. This strengthened the electrophilic attack ability toward CO2 and weakened the bond with the derived CO* species of the Fe active sites, associated with the excellent CO2 conversion and CO selectivity.

3.
Chem Soc Rev ; 49(5): 1385-1413, 2020 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-32067007

RESUMEN

The ever-increasing amount of anthropogenic carbon dioxide (CO2) emissions has resulted in great environmental impacts. The selective hydrogenation of CO2 to methanol, the first target in the liquid sunshine vision, not only effectively mitigates the CO2 emissions, but also produces value-added chemicals and fuels. This critical review provides a comprehensive view of the significant advances in heterogeneous catalysis for methanol synthesis through direct hydrogenation of CO2. The challenges in thermodynamics are addressed first. Then the progress in conventional Cu-based catalysts is discussed in detail, with an emphasis on the structural, chemical, and electronic promotions of supports and promoters, the preparation methods and precursors of Cu-based catalysts, as well as the proposed models for active sites. We also provide an overview of the progress in noble metal-based catalysts, bimetallic catalysts including alloys and intermetallic compounds, as well as hybrid oxides and other novel catalytic systems. The developments in mechanistic aspects, reaction conditions and optimization, as well as reactor designs and innovations are also included. The advances in industrial applications for methanol synthesis are further highlighted. Finally, a summary and outlook are provided.

4.
J Cell Biochem ; 120(10): 17573-17583, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31111550

RESUMEN

Non-small cell lung cancer (NSCLC) is still an unresolved source of tumor-related death internationally. Current studies have discovered that microRNAs (miRNAs) are associated with diverse cancers development, including NSCLC. Our paper focused on the functional character of miR-4286 in NSCLC. miR-4286 level in 68 cases of NSCLC tissues, matched neighboring nontumor tissues and different cancer cell lines were inspected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The connection concerning miR-4286 expression and clinicopathological features of patients with NSCLC were further determined. After knockdown or overexpression of miR-4286, cell viability, cell cycle, and/or apoptotic cells were examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assay, respectively. Moreover, the cell cycle- and apoptosis-related proteins were estimated by qRT-PCR and Western blot. In comparison with the matched nontumor tissues, miR-4286 was significantly enhanced in lung malignancy tissues and different cell lines. miR-4286 expression was related with the tumor-node-metastasis stage, lymphatic metastasis, and distant metastasis. Cell viability was ominously weakened by suppression of miR-4286 in A549 cells, whereas was statistically upregulated by overexpression of miR-4286 in NCI-H1299 cells. Additionally, we detected that suppression of miR-4286 tempted cell cycle arrest in G1 stage and fortified apoptosis in A549 cells. Runx3 was recognized as one target gene of miR-4286, and the impacts of suppression of miR-4286 on cell viability and apoptosis were through regulation of Runt-related transcription factor 3. Our study suggests that miR-4286 overexpression represents a tumor promoter role in NSCLC cells.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , MicroARNs/genética , Pronóstico , Células A549 , Adulto , Anciano , Apoptosis/genética , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/patología , Puntos de Control del Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología
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