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Org Biomol Chem ; 19(39): 8487-8491, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34545904


An efficient and practical approach for the synthesis of medicinally important acridones was developed from anthranils and commercially available arylboronic acids by a tandem copper(I)-catalyzed electrophilic amination/Ag(I)-mediated oxidative annulation strategy. This new and straightforward protocol displayed a broad substrate scope (25 examples) and high functional group tolerance. What's more, a possible mechanistic proposal was also presented.

J Hazard Mater ; 416: 125930, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492860


The pollution of heavy metals and organic compounds has received increased attention in recent years. In the current study, a novel biochar-based iron oxide composite (FeYBC) was successfully synthesized using pomelo peel and ferric chloride solution through one-step process at moderate temperature. Results clearly demonstrate that FeYBC exhibited more efficient removal of Cr(VI) and/or phenol compared with the pristine biochar, and the maximum adsorption amounts of Cr(VI) and phenol by FeYBC could reach 24.37 and 39.32 mg g-1, respectively. A series of characterization data suggests that several iron oxides such as Fe2O3, Fe0, FeOOH and Fe3O4 were formed on the FeYBC surface as well as oxygen-containing groups. Thermodynamics study indicates that Cr(VI) and phenol adsorption by FeYBC were endothermic and exothermic processes, respectively. Langmuir adsorption isotherm and pseudo-second order models could better explain the Cr(VI) and phenol adsorption behaviors over FeYBC. The Cr(VI) adsorption might be primarily achieved through the ion exchange and surface complexation and reduction, whereas the π-π interaction and electron donor-acceptor complex mainly contributed to phenol adsorption. The findings indicate that the biochar-based iron oxide composites material was an efficient adsorbent for the remediation of industrial effluents containing Cr(VI) and phenol.

Poluentes Químicos da Água , Água , Adsorção , Carvão Vegetal , Cromo , Compostos Férricos , Cinética , Fenol , Poluentes Químicos da Água/análise
J Environ Manage ; 278(Pt 1): 111518, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113397


Nowadays, nanoscale zero valent iron (nZVI) has been extensively applied for the decontamination of various pollutants, but passivation of nZVI severely affects its reactivity in use. In this study, ultrasound (US)-assisted catalytic reduction of Cr(VI) by an acid mine drainage based nZVI (AMD-nZVI) coupling with FeS2 system was systematically examined. Results show that the presence of FeS2 and US induced a synergistic enhancement of Cr(VI) removal by AMD-nZVI. Nearly 98% of Cr(VI) removal was achieved by AMD-nZVI/FeS2/US process within 60 min under optimal reaction conditions. Several coexisting substances with lower concentration including Pb(II), Ni(II), bisphenol A (BPA) and 2,4-diclorophenol (2,4-DCP) could be effectively removed in simultaneous manner with Cr(VI) removal. The inhibitory order of water matrix species on Cr(VI) removal was NO3- > PO43- > HCO3- > Ca2+ > Mg2+ > Cl-, and a serious suppression effect was induced by humic acid (HA). Addition of ethylene diamine tetra-acetic acid (EDTA) and citric acid (CA) could enhance Cr(VI) removal rate. An enhanced reaction mechanism was proposed, which involved the regeneration of more Fe2+ and H+ by AMD-nZVI/FeS2/US process, leading to the reduction of Cr(VI) by AMD-nZVI and FeS2 into Cr(III) species inculding Cr2O3 and Cr(OH)3. This study well demonstrates that AMD-nZVI/FeS2/US process is considered as a potential candidate for the remediation of Cr(VI) in real wasterwater.

Ferro , Poluentes Químicos da Água , Ácidos , Adsorção , Cromo/análise , Água , Poluentes Químicos da Água/análise
Clin Otolaryngol ; 45(3): 394-401, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32058675


OBJECTIVES: To evaluate the clinical efficacy of a high-efficiency air purifier in patients with allergic rhinitis. DESIGN: We conducted a randomised, double-blind, clinical controlled trial with active and inactive versions of an air purifier. Our study included patients with allergic rhinitis who were sensitive to Artemisia pollen and treatment of the indoor environment using air filtration at night. We evaluated the clinical efficacy of indoor air filtration during the Artemisia pollen scattering season in Yulin City in Shanxi Province, China. SETTING: The First Hospital of Yulin (Yulin City, Shanxi Province, China). PARTICIPANTS: A total of 90 patients with allergic rhinitis who were sensitive to allergens of Artemisia pollen were randomly assigned to one of two groups in equal numbers. MAIN OUTCOME MEASURES: The primary outcome measure was the difference in visual analogue scale scores from baseline. Secondary outcomes were changes from baseline in nasal symptoms, allergy symptom scores, responses to the Rhinoconjunctivitis Quality of Life Questionnaire, Epworth Sleepiness Scale scores and tolerability scores for the air purifier. RESULTS: Based on the allergy symptom score, we found significant differences in rhinitis symptoms between the groups who used the active versus the inactive air purifier. CONCLUSIONS: The results of our investigation demonstrated the health benefits of particle filtration.

Filtros de Ar , Artemisia , Pólen/efeitos adversos , Rinite Alérgica/etiologia , Rinite Alérgica/terapia , Adulto , Poluição do Ar em Ambientes Fechados , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rinite Alérgica/diagnóstico , Resultado do Tratamento