Kinetic data of methane hydrate formation in the presence of purewater, brines with single salt and mixed salts, and aqueous solutionsof ethylene glycol (EG) and salt + EG were measured. A new kineticmodel of hydrate ...Kinetic data of methane hydrate formation in the presence of purewater, brines with single salt and mixed salts, and aqueous solutionsof ethylene glycol (EG) and salt + EG were measured. A new kineticmodel of hydrate formation for the methane + water systems wasdeveloped based on a four-step formation mechanism and reactionkinetics approach. The proposed kinetic model predicts the kineticbehavior of methane hydrate formation in pure water with goodaccuracy. The feasibility of extending the kinetic model to salt (s)and EG containing systems was explored.展开更多
The refrigerant mixture of ethanol aqueous was applied to the parallel type pulsating heat pipe (PHP). The operation characteristics of the PHP were analyzed by means of experiment and nonlinear chaotic theory. Moreov...The refrigerant mixture of ethanol aqueous was applied to the parallel type pulsating heat pipe (PHP). The operation characteristics of the PHP were analyzed by means of experiment and nonlinear chaotic theory. Moreover, the relationship between the running state and attractor was described. The results indicate that starting power, stable running power and dry burning transition power are about 64.08 W, 148.68 W and 234.0 W respectively. The cycle and amplitude of PHP initially decrease and then increase with the increasing power. However, the data are welldistributed in a certain range. The running state is in agreement with the attractors, and the changing process for attractors is as follows: the attractors first disperse in the whole phase space, then present mass status, and finally show band distribution.展开更多
A systematic study of air gap distance effects on the structure and properties of poly(vinyl butyral)hollow fiber membrane via thermally induced phase separation(TIPS)has been carried out.The results show that the hol...A systematic study of air gap distance effects on the structure and properties of poly(vinyl butyral)hollow fiber membrane via thermally induced phase separation(TIPS)has been carried out.The results show that the hollow fiber membrane prepared at air gap zero has no skin layer; the pore size near the outer surface is larger than that near the inner surface; and the special pore channel-like structure near the outer surface is formed,which is quite different with the typical sponge-like structure caused by TIPS and the finger-like structure caused by non-solvent induced phase separation(NIPS),because of the synergistic action of non-solvent induced phase separation at air gap zero.The pore size gradually decreases from outer surface layer to the intermediate layer,but increases gradually from intermediate layer to the inner surface layer.With the increase of air gap distance,the pore size near the outer surface gets smaller and a dense skin layer is formed,and the pore size gradually increases from the outer surface layer to the inner surface layer.Water permeability of the hollow fiber membrane decreases with air gap distance,the water permeability decreases sharply from 45.50×10-7 to 4.52×10-7 m3/(m2·s·kPa)as air gap increases from 0 to 10 mm at take-up speed of 0.236 m/s,further decreases from 4.52×10-7 to 1.00×10-8 m3/(m2·s·kPa)as the air gap increases from 10 to 40 mm.Both the breaking strength and the elongation increase with the increase of air gap distance.The breaking strength increases from 2.25 MPa to 4.19 MPa and the elongation increases from 33.9% to 132.6% as air gap increases from 0 mm to 40 mm at take-up speed 0.236 m/s.展开更多
β-FeOOH nanorods of 40 nm wide and 450 nm long were fabricated through precisely regulating the hydrolysis kinetics of Fe3＋ in polyethylene glycol and the concentration of C1- as the structure-directing agent. Detai...β-FeOOH nanorods of 40 nm wide and 450 nm long were fabricated through precisely regulating the hydrolysis kinetics of Fe3＋ in polyethylene glycol and the concentration of C1- as the structure-directing agent. Detailed structural and chemical analyses of the intermediates during the synthesis identified that the strong interaction between PEG and Fe3＋ modulated the hydrolysis kinetics of Fe3＋and prevented the aggregation of β-FeOOH nanorods; while C1- provided sufficient nucleation sites, stabilized the hollow channel of β-FeOOH, and more importantly induced the growth of the nanorods along [001] direction.展开更多
Objective： To explore the influence of charred Gossamer urocteae （CGU） on the functions of primary cultured mouse oral fibroblasts and reveal its mechanism in wound healing. Methods： CGU was extracted with differe...Objective： To explore the influence of charred Gossamer urocteae （CGU） on the functions of primary cultured mouse oral fibroblasts and reveal its mechanism in wound healing. Methods： CGU was extracted with different solvents and ethanol extract （EE）, ethyl acetate fraction （EF）, n-butanol fraction （BF） and aqueous fraction （AF） were obtained. The effects of different fractions on the proliferation, matrix metaUoproteinase-2,9 （MMP-2,9） activities, synthesis of collagen and tissue inhibitor of metalloproteinase 1 （TIMP-1） in the mouse oral fibroblasts were determined by MTT, gelatin zymography, chloramine-T method, and enzyme-linked immunosorbent assay （ELISA） respectively. Results： EE, EF and BF at high concentrations could significantly inhibit proliferation of fibroblasts （P〈0.05 or P〈0.01）, and at low concentrations EF and BF could promote proliferation of fibroblasts, and BF and AF could significantly inhibit collagen synthesis （P〈0.05 or P〈0.01）. EE, EF and AF at high concentrations could significantly increase the MMP-9 activity, and BF and AF could significantly inhibit synthesis of TIMP-1. Conclusion： CGU at high concentrations can inhibit the proliferations of fibroblasts and synthesis of collagen, and in healing of wound, CGU at high concentrations possibly has the functions of anti-fibrosis and anti-scar, and the mechanism to promote degradation of collagen is possibly related to the increase in MMP-9 activity and the inhibition of TIMP-1 synthesis.展开更多
基金Supported by the National Natural Science Foundation(No. 20003010) and Postdoctoral Research Foundation.
文摘Kinetic data of methane hydrate formation in the presence of purewater, brines with single salt and mixed salts, and aqueous solutionsof ethylene glycol (EG) and salt + EG were measured. A new kineticmodel of hydrate formation for the methane + water systems wasdeveloped based on a four-step formation mechanism and reactionkinetics approach. The proposed kinetic model predicts the kineticbehavior of methane hydrate formation in pure water with goodaccuracy. The feasibility of extending the kinetic model to salt (s)and EG containing systems was explored.
基金Supported by Tianjin Science and Technology Development Strategy Research Program(No.06YFGZGX18300)
文摘The refrigerant mixture of ethanol aqueous was applied to the parallel type pulsating heat pipe (PHP). The operation characteristics of the PHP were analyzed by means of experiment and nonlinear chaotic theory. Moreover, the relationship between the running state and attractor was described. The results indicate that starting power, stable running power and dry burning transition power are about 64.08 W, 148.68 W and 234.0 W respectively. The cycle and amplitude of PHP initially decrease and then increase with the increasing power. However, the data are welldistributed in a certain range. The running state is in agreement with the attractors, and the changing process for attractors is as follows: the attractors first disperse in the whole phase space, then present mass status, and finally show band distribution.
基金Project(21176264)supported by the National Natural Science Foundation of ChinaProject(11JJ2010)supported by the Natural Science Foundation of Hunan Province,China
文摘A systematic study of air gap distance effects on the structure and properties of poly(vinyl butyral)hollow fiber membrane via thermally induced phase separation(TIPS)has been carried out.The results show that the hollow fiber membrane prepared at air gap zero has no skin layer; the pore size near the outer surface is larger than that near the inner surface; and the special pore channel-like structure near the outer surface is formed,which is quite different with the typical sponge-like structure caused by TIPS and the finger-like structure caused by non-solvent induced phase separation(NIPS),because of the synergistic action of non-solvent induced phase separation at air gap zero.The pore size gradually decreases from outer surface layer to the intermediate layer,but increases gradually from intermediate layer to the inner surface layer.With the increase of air gap distance,the pore size near the outer surface gets smaller and a dense skin layer is formed,and the pore size gradually increases from the outer surface layer to the inner surface layer.Water permeability of the hollow fiber membrane decreases with air gap distance,the water permeability decreases sharply from 45.50×10-7 to 4.52×10-7 m3/(m2·s·kPa)as air gap increases from 0 to 10 mm at take-up speed of 0.236 m/s,further decreases from 4.52×10-7 to 1.00×10-8 m3/(m2·s·kPa)as the air gap increases from 10 to 40 mm.Both the breaking strength and the elongation increase with the increase of air gap distance.The breaking strength increases from 2.25 MPa to 4.19 MPa and the elongation increases from 33.9% to 132.6% as air gap increases from 0 mm to 40 mm at take-up speed 0.236 m/s.
基金supported by the National Natural Science Foundation of China (21025312, 21303193, 21321002)the National Key Basic Research Program of China (2013CB933100)
文摘β-FeOOH nanorods of 40 nm wide and 450 nm long were fabricated through precisely regulating the hydrolysis kinetics of Fe3＋ in polyethylene glycol and the concentration of C1- as the structure-directing agent. Detailed structural and chemical analyses of the intermediates during the synthesis identified that the strong interaction between PEG and Fe3＋ modulated the hydrolysis kinetics of Fe3＋and prevented the aggregation of β-FeOOH nanorods; while C1- provided sufficient nucleation sites, stabilized the hollow channel of β-FeOOH, and more importantly induced the growth of the nanorods along [001] direction.
文摘Objective： To explore the influence of charred Gossamer urocteae （CGU） on the functions of primary cultured mouse oral fibroblasts and reveal its mechanism in wound healing. Methods： CGU was extracted with different solvents and ethanol extract （EE）, ethyl acetate fraction （EF）, n-butanol fraction （BF） and aqueous fraction （AF） were obtained. The effects of different fractions on the proliferation, matrix metaUoproteinase-2,9 （MMP-2,9） activities, synthesis of collagen and tissue inhibitor of metalloproteinase 1 （TIMP-1） in the mouse oral fibroblasts were determined by MTT, gelatin zymography, chloramine-T method, and enzyme-linked immunosorbent assay （ELISA） respectively. Results： EE, EF and BF at high concentrations could significantly inhibit proliferation of fibroblasts （P〈0.05 or P〈0.01）, and at low concentrations EF and BF could promote proliferation of fibroblasts, and BF and AF could significantly inhibit collagen synthesis （P〈0.05 or P〈0.01）. EE, EF and AF at high concentrations could significantly increase the MMP-9 activity, and BF and AF could significantly inhibit synthesis of TIMP-1. Conclusion： CGU at high concentrations can inhibit the proliferations of fibroblasts and synthesis of collagen, and in healing of wound, CGU at high concentrations possibly has the functions of anti-fibrosis and anti-scar, and the mechanism to promote degradation of collagen is possibly related to the increase in MMP-9 activity and the inhibition of TIMP-1 synthesis.
