Using viscose fiber (VF) as starting material and common steam as activating agent, formation of oxygen structures in activated carbon fiber is investigated. In the preparation of samples, VF was first heated at tempe...Using viscose fiber (VF) as starting material and common steam as activating agent, formation of oxygen structures in activated carbon fiber is investigated. In the preparation of samples, VF was first heated at temperatures between 450℃ and 900℃ in N_2 artmosphere. Then, in a successive activation stage, the product carbonized at 600℃ was activated in steam at 450-900℃ for 30 min, and at 600℃ for 5-30 min. The other carbonization products were activated at 600 and 900℃ for 30 min respectively. The products activated at 900℃ were then activated at 450℃ for 30 min again. The starting materiah carbonized products and all activation products were examined by FT-IR spectroscopy and some products were examined by X-ray photoelectron spectroscope (XPS). And the yields of the carbonized and activated products were calculated. By analysing these spectra, the amount of oxygen-containing functional groups of the activated products attained under various activation time, various activation temperature and various previous carbonization temperature was determined.展开更多
The activated carbon fiber（ACF） was prepared from polyacrylonitrile-based pre-oxidized fiber（PANOF） by KOH direct activation. The influence of activation conditions including impregnation ratio（the mass ratio of ...The activated carbon fiber（ACF） was prepared from polyacrylonitrile-based pre-oxidized fiber（PANOF） by KOH direct activation. The influence of activation conditions including impregnation ratio（the mass ratio of PANOF to KOH）, activation temperature and activation time on the pore structure and electrochemical properties of ACF was investigated, and the corresponding activation mechanism was proposed. The ACF prepared at an activation temperature of 800℃ and an impregnation ratio（the mass ratio of PANOF to KOH） of 1：2 for an activation time of 1 b in 6 mol/L KOH solution exhibits a specific surface area of 3029 m^2/g, a mesoporosity of 84.2% and a specific capacitance of 288 F/g, and shows a good capacitive performance. The prepared ACF can be used as the electrode material for supercapacitors.展开更多
The animal experiment of viscose carbon fiber based C/C composites applied in bone defection intramedullary fixation was carried out in New Zealand white rabbits.The histological observation on the 100th day after sur...The animal experiment of viscose carbon fiber based C/C composites applied in bone defection intramedullary fixation was carried out in New Zealand white rabbits.The histological observation on the 100th day after surgical operation indicated that the experimental animals recovered well and the bone defect area was reconstructed by new bone trabecula.Immunohistochemical observation of leukocyte common antigen and macrophage suggested that intramedullary fixation materials did not induct any chronic toxicity reactions such as inflammatory reactions,macrophage reactions and formation of granulation tissue.The tissue compatibility of this material was excellent.Meanwhile,the impurity element species and the biological toxic element content of viscose fiber based C/C composites were determined by atomic fluorescence analyzer and inductively coupled plasma atomic emission spectrometry.The results reveal that there are few biological toxic elements in the viscose fiber based C/C composites and it can satisfy the constituent demands of surgical implants.展开更多
Viscose activated carbon fibers （ACFs） were characterized using specific surface area, scanning electron modified with chemical vapor deposition （CVD）. The samples were microscopy （SEM）, pore size distribution a...Viscose activated carbon fibers （ACFs） were characterized using specific surface area, scanning electron modified with chemical vapor deposition （CVD）. The samples were microscopy （SEM）, pore size distribution and Fourier transform infrared spectroscopy （FTIR）. Batch adsorption experiments were carried out to investigate the adsorption behavior of modified ACFs for methyl orange（MO） from its aqueous solutions. The results show that the adsorption isotherms of MO onto modified ACFs well follows the Langmuir isotherm equation. The adsorption kinetics of MO can be well described by the pseudo second-order kinetic model. The adsorption process involves the intra-particle diffusion, but is not the only rate-controlling step. Thermodynamic parameters including AG, AH and AS were calculated, suggesting that the adsorption of MO onto modified ACFs is a spontaneous, exothermic and physisorption process. FTIR result indicates that the major adsorption mechanism of modified ACFs for MO is hydrogen bond.展开更多
文摘Using viscose fiber (VF) as starting material and common steam as activating agent, formation of oxygen structures in activated carbon fiber is investigated. In the preparation of samples, VF was first heated at temperatures between 450℃ and 900℃ in N_2 artmosphere. Then, in a successive activation stage, the product carbonized at 600℃ was activated in steam at 450-900℃ for 30 min, and at 600℃ for 5-30 min. The other carbonization products were activated at 600 and 900℃ for 30 min respectively. The products activated at 900℃ were then activated at 450℃ for 30 min again. The starting materiah carbonized products and all activation products were examined by FT-IR spectroscopy and some products were examined by X-ray photoelectron spectroscope (XPS). And the yields of the carbonized and activated products were calculated. By analysing these spectra, the amount of oxygen-containing functional groups of the activated products attained under various activation time, various activation temperature and various previous carbonization temperature was determined.
基金Supported by the National Natural Science Foundation of China（No.21273097） and the Key Project of Jilin Province, China（No.20126010）.
文摘The activated carbon fiber（ACF） was prepared from polyacrylonitrile-based pre-oxidized fiber（PANOF） by KOH direct activation. The influence of activation conditions including impregnation ratio（the mass ratio of PANOF to KOH）, activation temperature and activation time on the pore structure and electrochemical properties of ACF was investigated, and the corresponding activation mechanism was proposed. The ACF prepared at an activation temperature of 800℃ and an impregnation ratio（the mass ratio of PANOF to KOH） of 1：2 for an activation time of 1 b in 6 mol/L KOH solution exhibits a specific surface area of 3029 m^2/g, a mesoporosity of 84.2% and a specific capacitance of 288 F/g, and shows a good capacitive performance. The prepared ACF can be used as the electrode material for supercapacitors.
基金the Fundamental Research Funds for the Central Universities of China(No.11CX04033A)the Postdoctoral Innovation Projection of Shandong Province(No.201103085)
文摘The animal experiment of viscose carbon fiber based C/C composites applied in bone defection intramedullary fixation was carried out in New Zealand white rabbits.The histological observation on the 100th day after surgical operation indicated that the experimental animals recovered well and the bone defect area was reconstructed by new bone trabecula.Immunohistochemical observation of leukocyte common antigen and macrophage suggested that intramedullary fixation materials did not induct any chronic toxicity reactions such as inflammatory reactions,macrophage reactions and formation of granulation tissue.The tissue compatibility of this material was excellent.Meanwhile,the impurity element species and the biological toxic element content of viscose fiber based C/C composites were determined by atomic fluorescence analyzer and inductively coupled plasma atomic emission spectrometry.The results reveal that there are few biological toxic elements in the viscose fiber based C/C composites and it can satisfy the constituent demands of surgical implants.
基金Project (50802115) supported by the National Natural Science Foundation of ChinaProject (2010FJ4075) supported by Science and Technology Planning Project of Hunan Province, China+1 种基金Project (CDJJ-10010205) supported by the Science Foundation of Changsha University, ChinaProject supported by the Construct Program of the Key Discipline in Hunan Province, China
文摘Viscose activated carbon fibers （ACFs） were characterized using specific surface area, scanning electron modified with chemical vapor deposition （CVD）. The samples were microscopy （SEM）, pore size distribution and Fourier transform infrared spectroscopy （FTIR）. Batch adsorption experiments were carried out to investigate the adsorption behavior of modified ACFs for methyl orange（MO） from its aqueous solutions. The results show that the adsorption isotherms of MO onto modified ACFs well follows the Langmuir isotherm equation. The adsorption kinetics of MO can be well described by the pseudo second-order kinetic model. The adsorption process involves the intra-particle diffusion, but is not the only rate-controlling step. Thermodynamic parameters including AG, AH and AS were calculated, suggesting that the adsorption of MO onto modified ACFs is a spontaneous, exothermic and physisorption process. FTIR result indicates that the major adsorption mechanism of modified ACFs for MO is hydrogen bond.
