RESUMO
Manufacturing high-performance activated carbon (AC) materials from abundant biomass at low temperature and short activation time is targeted by the green and sustainable chemical industry. Here, a 1980 m2/g of carbon nanospheres-anchored porous carbon material (PHAC) derived from waste sawdust was prepared by a method of H3PO4 hydrothermal combined with fast activation at 450 °C within 2.8 min. It is found that H3PO4 hydrothermal pretreatment could promote the dehydration of carbohydrates to form more unstable C = O structures, which were decomposed in the subsequent fast activation to form pore structures. In addition, this process is also conducive to the formation of carbon nanospheres, increasing the degree of graphitization and producing more graphite defects. The prepared PHAC showed good adsorption performance for different types of pollutants. This work provides a new insight for the preparation of high performance biomass based carbon materials under mild conditions.
Assuntos
Nanosferas , Adsorção , Biomassa , Carvão Vegetal , PorosidadeRESUMO
OBJECTIVE: To investigate the long-term effect and the key factors associated with relapse of double embolization of bronchial artery in patients with lung tuberculosis and hemoptysis. METHODS: Fifty patients with lung tuberculosis and hemoptysis receiving the radiography and double embolization of bronchial artery (BAG + BAE) had been followed up for two years. The causes for hemoptysis relapse was determined, followed by specific treatment, and the effect was evaluated. Among them, 37 were males, 13 females, with the age of 8-75 years (mean age 47.6 years). RESULTS: The 2 year follow-up showed that the cure rate and the effective rate were 62% (31/50) and 94% (47/50) respectively. In a short term after embolization, hemoptysis relapsed in 9 cases, the major causes being active tuberculosis and secondary bronchiectasis complicated with infection. Other responsible factors included missed-embolization of bronchial artery and remaining blood supply from systemic circulation. In mid and long term follow-up, hemoptysis relapsed in 10 cases, the major causes being secondary pulmonary mycotic infection and recurrence of tuberculosis. CONCLUSIONS: The long term result of double embolization of bronchial artery in patients with lung tuberculosis and hemoptysis was significant. It could prevent the danger from massive hemoptysis, and therefore allows the medical therapy for tuberculosis. Embolization of bronchial artery is effective for hemostasis, while etiologic therapy aimed at removing the infection leading to chronic inflammation is the cure for tuberculosis and hemoptysis.