Feather, as a by-product of the poultry industry, has long been treated as a solid waste, which causes environ- mental and economic problems. In this work, the hydrolyzed feather keratin （HFK） was extracted from the...Feather, as a by-product of the poultry industry, has long been treated as a solid waste, which causes environ- mental and economic problems. In this work, the hydrolyzed feather keratin （HFK） was extracted from the chicken feather using a cost-effective method of alkali-extraction and acid-precipitation by applying urea and sodium sulfide. The aim was development and characterization of the eco-friendly films based on the HFK with variable glycerol contents by a thermoplastic process. The thermal analysis showed that high temperature and high pres- sure improved the compatibility between the glycerol and the HFI（ molecules. Also it was shown that the addi- tion of water is necessary in the hot-pressing process of films, The FT-IR analysis indicated that the formation of the new hydrogen bonds between HFK and glycerol. By increasing the glycerol content, the film tensile strength （orb ） decreases from 10,5 MPa to 5.7 MPa and the solubility increases from 15.3% to 20.9%, while the elongation at break （εb） achieves the maximum value of 63,8% for the film with 35% glycerol. The swelling was just below 16.9% at 25 ℃ for 24 h, suggesting a good stability of the films in water. The water vapor permeability （WVP） varied between 3.02 x 10 ^10g. m 2. s-1 . pa-1 and 4.11 x 10-10g · m-2 · s-1 · Pa-1 for the films with 20%and 40% glycerol, respectively. The HFK film was uniform, translucent and tough, which could be used in packaging and agricultural field.展开更多
This paper critically reviews Hossein Nassaji's Language Learning article, which systematically overviews the recent language processing theories, it is especially pertinent to schema theory as well as Walter Kint...This paper critically reviews Hossein Nassaji's Language Learning article, which systematically overviews the recent language processing theories, it is especially pertinent to schema theory as well as Walter Kintsch's construction-integration (CI) theory in reading comprehension. The article thoroughly investigates the unified theory (as Kintsch defines), construction-integration theory in text comprehension, which is mainly based upon the comparison with and analysis of the applications of schema theory from the perspective of language reading comprehension. The author tries to work out and illustrate this model as an alternative approach to the schema-oriented models previously used to solve reading comprehension problems in language teaching and leaning.展开更多
Based on two sets of studies on individual differences in mental representation construction (e.g., Gernsbacher, et al. 1990, 1991, 2001; Oakhill, et al. 1988, 1996, 2003), the present study investigates whether high-...Based on two sets of studies on individual differences in mental representation construction (e.g., Gernsbacher, et al. 1990, 1991, 2001; Oakhill, et al. 1988, 1996, 2003), the present study investigates whether high-level/proficiency Chinese English majors are better at mental representation construction than those with low proficiency by comparing their performances in summary writing in Chinese after reading a passage in English. Statistical analyses show that such differences do exist in that the sophom...展开更多
基金Supported by the National Natural Science Foundation of China(21176269,31371880,31401526)Higher School Science and Technology Innovation Project of Guangdong Province(2013KJCX0102)Science and Technology Plan Project of Guangdong Province(2013B010403029)
文摘Feather, as a by-product of the poultry industry, has long been treated as a solid waste, which causes environ- mental and economic problems. In this work, the hydrolyzed feather keratin （HFK） was extracted from the chicken feather using a cost-effective method of alkali-extraction and acid-precipitation by applying urea and sodium sulfide. The aim was development and characterization of the eco-friendly films based on the HFK with variable glycerol contents by a thermoplastic process. The thermal analysis showed that high temperature and high pres- sure improved the compatibility between the glycerol and the HFI（ molecules. Also it was shown that the addi- tion of water is necessary in the hot-pressing process of films, The FT-IR analysis indicated that the formation of the new hydrogen bonds between HFK and glycerol. By increasing the glycerol content, the film tensile strength （orb ） decreases from 10,5 MPa to 5.7 MPa and the solubility increases from 15.3% to 20.9%, while the elongation at break （εb） achieves the maximum value of 63,8% for the film with 35% glycerol. The swelling was just below 16.9% at 25 ℃ for 24 h, suggesting a good stability of the films in water. The water vapor permeability （WVP） varied between 3.02 x 10 ^10g. m 2. s-1 . pa-1 and 4.11 x 10-10g · m-2 · s-1 · Pa-1 for the films with 20%and 40% glycerol, respectively. The HFK film was uniform, translucent and tough, which could be used in packaging and agricultural field.
文摘This paper critically reviews Hossein Nassaji's Language Learning article, which systematically overviews the recent language processing theories, it is especially pertinent to schema theory as well as Walter Kintsch's construction-integration (CI) theory in reading comprehension. The article thoroughly investigates the unified theory (as Kintsch defines), construction-integration theory in text comprehension, which is mainly based upon the comparison with and analysis of the applications of schema theory from the perspective of language reading comprehension. The author tries to work out and illustrate this model as an alternative approach to the schema-oriented models previously used to solve reading comprehension problems in language teaching and leaning.
文摘Based on two sets of studies on individual differences in mental representation construction (e.g., Gernsbacher, et al. 1990, 1991, 2001; Oakhill, et al. 1988, 1996, 2003), the present study investigates whether high-level/proficiency Chinese English majors are better at mental representation construction than those with low proficiency by comparing their performances in summary writing in Chinese after reading a passage in English. Statistical analyses show that such differences do exist in that the sophom...
