RESUMEN
A magnetic carbon composite, Fe3O4/C composite, was fabricated by one-step hydrothermal synthesis, modified by heat treatment under an inert atmosphere (N2), and then used as an adsorbent for ciprofloxacin (CIP) removal. Conditions for the modification were optimized according to the rate of CIP removal. The adsorbent was characterized by Fourier transform infrared spectroscopy, X-ray diffraction measurements, vibrating-sample magnetometry, scanning electron microscopy, transmission electron microscopy, and N2 adsorption/desorption isotherm measurements. The results indicate that the modified adsorbent has substantial magnetism and has a large specific area, which favor CIP adsorption. The effects of solution pH, adsorbent dose, contact time, initial CIP concentration, ion strength, humic acid and solution temperature on CIP removal were also studied. Our results show that all of the above factors influence CIP removal. The Langmuir adsorption isotherm fits the adsorption process well, with the pseudo second-order model describing the adsorption kinetics accurately. The thermodynamic parameters indicate that adsorption is mainly physical adsorption. Recycling experiments revealed that the behavior of adsorbent is maintained after recycling for five times. Overall, the modified magnetic carbon composite is an efficient adsorbent for wastewater treatment.
Asunto(s)
Ciprofloxacina/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Adsorción , Carbono , Ciprofloxacina/análisis , Sustancias Húmicas , Concentración de Iones de Hidrógeno , Cinética , Magnetismo , Concentración Osmolar , Termodinámica , Contaminantes Químicos del Agua/análisisRESUMEN
A series of iron oxide sorbents with novel structures of three-dimensionally ordered macropores (3DOM), ranging in size from 60 to 550 nm, were fabricated and creatively used as sorbents for the removal of H2S at medium temperatures of 300-350 °C. Evaluation tests using thermogravimetric analysis (TGA) and a fixed-bed reactor showed that, in comparison to the iron oxide sorbent prepared by a conventional mixing method, the fabricated iron oxide sorbent with a 3DOM structure exhibited much higher reactivity and efficiency, as well as high sorbent utilization with low regeneration temperature. The excellent performance of 3DOM iron oxide as a sulfur sorbent is attributed to its special texture, i.e., the open and interconnected macroporous, large surface area, and nanoparticles of iron oxide, which are revealed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen adsorption techniques. The investigation results of the pore effect on the performance of the sorbent show that sorbents with pores size around 150 nm in diameter revealed the best performance. The reason is that pores of this size are large enough to allow gas to pass through even if the channel is partially blocked during the reaction process while remaining a large surface area that can provide more active sites for the reaction.
Asunto(s)
Compuestos Férricos/química , Calor , Sulfuro de Hidrógeno/aislamiento & purificación , Adsorción , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Difracción de Rayos XRESUMEN
The aim of this study was to investigate QoL (quality of life) of patients with esophageal cancer in northern Henan province, China, and to accurate evaluate and reflect the relationship between patient characteristics and QoL. In the high risk area of esophageal cancer in the north of Henan province, 735 patients with esophageal cancer were investigated. The Eysenck personality questionnaire (EPQ) and QoL were analyzed by using the questionnaire of general situation, EPQ, QLQ-C30 and QLQ-OES18. The effects of personal character on the QoL of esophageal carcinoma patients were analyzed by SPSS 11.0 software. The QoL of esophageal cancer patients in Northern Henan region was significantly affected by character. The difference between choleric and type of melancholic temperament types was significant (P<0.01), also in OESEAT, OESTA, OESCO and OESSP (P<0.05). Differences in personal character can thus influence the quality of esophageal cancer patient lives.
Asunto(s)
Carácter , Neoplasias Esofágicas/psicología , Calidad de Vida , Sobrevivientes/psicología , Temperamento , Adulto , Anciano , Anciano de 80 o más Años , China , Neoplasias Esofágicas/cirugía , Esofagectomía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inventario de Personalidad , Pronóstico , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Understanding the conversion of coal-N during gasification is an important part of the development of gasification-based power generation technologies to reduce NO(x) emissions from coal utilization. This study investigated the conversion of coal-N in the presence of NO during the gasification of three rank-ordered coals and their chars in steam and low-concentration O(2). Our results show that NO can be incorporated into the char structure during gasification. The inherent char-N and the N incorporated into the char from NO-char reactions behave very similarly during gasification. During the gasification in steam, significant amounts of HCN and NH(3) can be formed from the incorporated N structure in char, especially for the relatively "aged" chars, mainly due to the availability of abundant H radicals on the char surface during the gasification in steam. During the gasification in 2000 ppm O(2), the formation of HCN or NH(3) from the N structures in char, including those incorporated into the char from the NO-char reactions, was not a favored route of reaction mainly due to the lack of H on char surface in the presence of O(2).