RESUMO
Photocatalysis was an attractive strategy that had potential to tackle the Microcystin-LR (MC-LR) contamination of aquatic ecosystems. Herein, magnetic photocatalyst Fe3O4/Bi2WO6/Reduced graphene oxide composites (Bi2WO6/Fe3O4/RGO) were employed to degrade MC-LR. The removal efficiency and kinetic constant of the optimized Bi2WO6/Fe3O4/RGO (Bi2WO6/Fe3O4-40%/RGO) was 1.8 and 2.3 times stronger than the pure Bi2WO6. The improved activity of Bi2WO6/Fe3O4-40%/RGO was corresponded to the expanded visible light adsorption ability and reduction of photogenerated carrier recombination efficiency through the integration of Bi2WO6 and Fe3O4-40%/RGO. The MC-LR removal efficiency exhibited a positive tendency to the initial density of algae cells, fulvic acid, and the concentration of MC-LR decreased. The existed anions (Cl-, CO3-2, NO3-, H2PO4-) reduced MC-LR removal efficiency of Bi2WO6/Fe3O4-40%/RGO. The Bi2WO6/Fe3O4-40%/RGO could degrade 79.3% of MC-LR at pH = 7 after 180 min reaction process. The trapping experiments and ESR tests confirmed that the h+, âOH, and âO2- played a significant role in MC-LR degradation. The LC-MS/MS result revealed the intermediates and possible degradation pathways.
Assuntos
Bismuto , Grafite , Luz , Toxinas Marinhas , Microcistinas , Microcistinas/química , Microcistinas/efeitos da radiação , Grafite/química , Bismuto/química , Poluentes Químicos da Água/química , Fotólise , CatáliseRESUMO
Developing heterostructure photocatalysts for removing Microcystin-LR (MC-LR) under visible light was of positive significance to control the risk of Microcystins and ensure the safety of water quality. Herein, the Bi2WO6/Reduced graphene oxide (RGO) nanocomposites were prepared via a simple one-spot hydrothermal method for the first time to degrade MC-LR. The optimized Bi2WO6/RGO (Bi2WO6/RGO3%) achieved a removal efficiency of 82.3% toward MC-LR, with 1.9-fold higher efficiencies than Bi2WO6, and it showed superior reusability and high stability after 5 cycles. The degradation efficiency of MC-LR demonstrated a negative trend with the initial concentration of MC-LR, fulvic acid, and initial algal density increased, while MC-LR removal rate for the presence of anions was in the order of Cl- > CO3-2 > NO3- > H2PO4-. The degradation efficiency of MC-LR could reach up to 82.3% within 180 min in the neutral condition. The active species detection experiments and EPR measurements demonstrated that the holes (h+), hydroxide radicals (âOH), and superoxide radicals (âO2-) participated in the degradation of MC-LR. The DFT calculations showed that 0.56 of electron transferred from Bi2WO6 to RGO, indicating RGO introduction could prevent the recombination of photoelectrons and holes and was beneficial for MC-LR degradation. Finally, the possible intermediate products and degradation pathways were also proposed by the LC-MS/MS analysis.
Assuntos
Microcistinas , Espectrometria de Massas em Tandem , Microcistinas/química , Teoria da Densidade Funcional , Cromatografia Líquida , LuzRESUMO
OBJECTIVE: To establish and promote the non-contact doctor-patient interactive diagnosis and treatment mode based on mobile internet for the treatment of coronavirus disease 2019 (COVID-19) with moxibustion therapy, and to observe the feasibility and effectiveness of the model in the pandemic. METHODS: A total of 43 first-line medical staff and 149 suspected and confirmed cases with COVID-19 [18 cases in medical observation period, 17 cases of mild type (cold dampness and stagnation in the lung), 24 cases of ordinary type (cold-dampness accumulated in the lung) and 90 cases in recovery period (qi deficiency of spleen and lung)] were included. A non-contact doctor-patient interactive diagnosis and treatment platform was established for the treatment of COVID-19 with indirect moxibustion plaster based on mobile internet. By the platform, the patients were instructed to use indirect moxibustion plaster in treatment. For the first-line medical staff and patients in the medical observation period, Zusanli (ST 36), Qihai (CV 6) and Zhongwan (CV 12) were selected. For the mild cases (cold dampness and stagnation in the lung) and the cases of ordinary type (cold-dampness accumulated in the lung), Hegu (LI 4), Taichong (LR 3), Zusanli (ST 36) and Guanyuan (CV 4) were selected. In the recovery period (qi deficiency of spleen and lung), Dazhui (GV 14), Feishu (BL 13), Geshu (BL 17), Zusanli (ST 36) and Kongzui (LU 6) were used. The treatment was given once daily for 40 min each time. The intervention lasted for 10 days. After intervention, the infection rate and the improvement in the symptoms and psychological status of COVID-19 were observed in clinical first-line medical staff and COVID-19 patients. RESULTS: In 10 days of intervention with indirect moxibustion plaster, there was "zero" infection among medical staff. Of 43 first-line physicians and nurses, 33 cases had some physical symptoms and psychological discomforts, mainly as low back pain, poor sleep and anxiety. After treatment, regarding the improvements in the symptoms and psychological discomforts, the effective rate was 78.8% (26/33) and the curative rate was 36.4% (12/33). Regarding the improvements in psychological discomforts, the effective rate was 58.3% (14/24) and the curative rate was 37.5 (9/24). Of 149 patients, 133 cases had the symptoms and psychological discomforts. After treatment, regarding the improvements in the symptoms and psychological discomforts, the effective rate was 81.2% (108/133) and the curative rate was 34.6% (46/133). Regarding the improvements in psychological discomforts, the effective rate was 76.5% (52/68) and the curative rate was 57.4 % (39/68). CONCLUSION: It is feasible to apply the indirect moxibustion plaster technique based on mobile internet to the treatment COVID-19. This mode not only relieves the symptoms such as cough and fatigue, improves psychological state, but also possibly prevents the first-line medical staff from COVID-19.
Assuntos
Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Moxibustão , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Consulta Remota , Pontos de Acupuntura , Betacoronavirus , COVID-19 , Pessoal de Saúde , Humanos , SARS-CoV-2RESUMO
Olive trees, originated from Mediterranean, have been cultivated in China for decades and show great adaption to local environment. However, research on this topic is limited. In this study, the major qualitative characteristics and changes of olive grown in southwest China were investigated. The results showed that oil accumulated during fruit development and reached its maximum value when fruit had fully ripened. Phenolic and flavonoid contents increase rapidly in the early growth stage (0-90 DAFB) and then begin to decrease as fruit ripens. Compared with olive from the Mediterranean, olive from China has special characteristics: higher moisture content in the fruit combined with lower percentages of unsaturated fatty acids and oil content. This is due to southwest China's climate which is wetter and cooler compared to the Mediterranean. Our study suggests that southwest China's higher annual rainfall might contribute to higher fruit moisture content while its low temperatures would be conducive to higher unsaturated fatty acid levels in the fruit.