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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(2): 328-333, 2023 Mar.
Artículo en Zh | MEDLINE | ID: mdl-36949694

RESUMEN

Stomatology textbooks are an important carrier of integrated ideological and political education. The preparation of textbooks for the stomatology specialty in the new era is an important issue of concern for administrators and teachers of higher education institutions. Integrating ideological and political education in the instruction and practice composnents of academic courses on stomatology is an important issue to be resolved. Herein, we introduced the significance of ideological and political education and elaborated on the method of integrating ideological and political education in stomatology courses and textbooks from the perspectives of curriculum design, textbook compilation, teacher training, teaching evaluation, etc. We analyzed the different ways of integrating ideological and political education in stomatology courses and textbooks from the perspectives of classroom instruction, clinical practice, campus culture, social activities, and some other aspects.


Asunto(s)
Medicina Oral , Escolaridad , Curriculum , Instituciones Académicas , Universidades
2.
Bioresour Technol ; 408: 131167, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39067708

RESUMEN

Little is known about the synergistic effects of abiotic aging and biodegradation on microplastics (MPs) transformation in the environment. Herein, a hybrid process of MPs degradation was proposed by analyzing the effect of microorganisms and abiotic aging on aging MPs and non-aging MPs degradation during composting. The results showed that composting facilitated the oxidation and depolymerization of aging MPs, and its degradation efficiency was about three times that of non-aging MPs. Further investigation revealed that aging MPs contained higher abundance of plastic-degrading bacteria and enzyme activity than non-aging MPs. In addition, free radicals also influenced the degradation of MPs. However, path model and shielding experiments confirmed that free radicals mainly facilitated the non-aging MPs degradation (contribution was 68.8 %), while aging MPs was easily degraded by microorganisms (contribution was 72.6 %). This study provides promising strategies for scaling up plastic treatment in bioreactors through a hybrid collaboration of biological and abiotic processes.


Asunto(s)
Biodegradación Ambiental , Compostaje , Microplásticos , Microplásticos/metabolismo , Compostaje/métodos , Bacterias/metabolismo , Plásticos/metabolismo , Radicales Libres/metabolismo
3.
J Hazard Mater ; 449: 131031, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-36821904

RESUMEN

It has been increasingly documented that the hydroxyl radical (•OH) can promote the transformation of organic contaminants such as microplastics (MPs) in various environments. However, few studies have sought to identify an ideal strategy for accelerating in situ MPs degradation through boosting the process of •OH production in practical applications. In this work, iron-mineral-supplemented thermophilic composting (imTC) is proposed and demonstrated for enhancing in situ degradation of sludge-based MPs through strengthening •OH generation. The results show that the reduction efficiency of sludge-based MPs abundance was about 35.93% in imTC after treatment for 36 days, which was 38.99% higher than that of ordinary thermophilic composting (oTC). Further investigation on polyethylene-microplastics (PE-MPs) suggested that higher abundance of •OH (the maximum value was 408.1 µmol·kg-1) could be detected on the MPs isolated from imTC through microbially-mediated redox transformation of iron oxides, as compared to oTC. Analyses of the physicochemical properties of the composted PE-MPs indicated that increased •OH generation could largely accelerate the oxidative degradation of MPs. This work, for the first time, proposes a feasible strategy to enhance the reduction efficiency of MPs abundance during composting through the regulation of •OH production.


Asunto(s)
Compostaje , Microplásticos , Aguas del Alcantarillado , Plásticos , Hierro
4.
ChemSusChem ; 4(12): 1838-43, 2011 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-22105964

RESUMEN

The utilization of biomass has recently attracted tremendous attention as a potential alternative to petroleum for the production of liquid fuels and chemicals. We report an efficient alcohol-mediated reactive extraction strategy by which a hydrophobic mixture of butyl levulinate and formate esters, derived from cellulosic biomass, can be converted to valuable γ-valerolactone (GVL) by a simple supported gold catalyst system without need of an external hydrogen source. The essential role of the supported gold is to facilitate the rapid and selective decomposition of butyl formate to produce a hydrogen stream, which enables the highly effective reduction of butyl levulinate into GVL. This protocol simplifies the recovery and recycling of sulfuric acid, which is used for cellulose deconstruction.


Asunto(s)
Formiatos/química , Oro/química , Lactonas/síntesis química , Ácidos Levulínicos/química , Circonio/química , Biomasa , Catálisis , Celulosa/química
5.
Talanta ; 81(4-5): 1856-60, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20441986

RESUMEN

Urinary chromium speciation analysis can provide available information of the individual exposure levels of Cr(VI) compounds. An analytical method based on ion-pair reversed-phase HPLC combined with ICP-MS to simultaneously determine Cr(III) and Cr(VI) in human urine has been developed for assessing the occupational exposure to chromate. The separation conditions of the method, including the pH value, the concentrations of ion-pair reagent and methanol in the mobile phase were studied. Specially, a high-speed polyetheretherketone (PEEK) column and a typical sample introduction method were employed to avoid the exogenous chromium contamination during the analysis. The separation of Cr(III) and Cr(VI) could be finished within 4min with the detection limits as low as 0.03microgL(-1) at 100microL injections for both of them, providing a convenient method for routine analysis of chromium species. The chromium species in urine of chromate workers were monitored using the developed method. The statistical analysis showed a significant relationship (n=32, p<0.01) between the urinary Cr(VI) and the individual airborne exposure levels, indicating that the urinary Cr(VI) could be used as a convenient and suitable monitor for high level Cr(VI) occupational exposure.


Asunto(s)
Cromatos/química , Cromatografía Líquida de Alta Presión/métodos , Cromo/química , Cromo/orina , Espectrometría de Masas/métodos , Exposición Profesional , Adulto , Benzofenonas , Femenino , Humanos , Iones , Cetonas/química , Masculino , Metales/química , Persona de Mediana Edad , Polietilenglicoles/química , Polímeros , Semiconductores , Urinálisis/métodos
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