Through thermal test, cold state experiment, analysis and simulation of thermal process, the gas flow distribution in pelletizing shaft furnace （PSF） was discussed. The results show that there are five flowing trend...Through thermal test, cold state experiment, analysis and simulation of thermal process, the gas flow distribution in pelletizing shaft furnace （PSF） was discussed. The results show that there are five flowing trends among them, the downward roasting gas and the upward cooling gas are the most unsteady, which influence flow distribution greatly. Among the operating parameters, the ratio of inflow is a key factor affecting the flow distribution. The roasting and cooling gases will entirely flow into the roasting zone and internal vertical air channels （IVAC）, respectively, if the ratio of inflow is critical. From such a critical operating condition increasing roasting gas flow or decreasing cooling gas flow, the roasting gas starts flowing downwards so as to enter the inside of IVAC the greater the ratio of inflow, the larger the downward flowrate. Among constructional parameters, the width of roasting zone b1, width of IVAC b2 and width of cooling zone b3, and the height of roasting zone h1, height of soaking zone h2 and height of cooling zone hs are the main factors affecting flow distribution. In case the ratio of b2/b3, or h3/h2, or h1/h2 is increased, the upward cooling gas tends to decrease while the downward roasting gas tends to increase with a gradual decrease in the ratio of inflow.展开更多
The influences of both the volume of PS/toluene solution in the Ubbelohde viscometer and the precision of the time measuring on the viscosity behavior in dilute and extremely dilute concentration region are investigat...The influences of both the volume of PS/toluene solution in the Ubbelohde viscometer and the precision of the time measuring on the viscosity behavior in dilute and extremely dilute concentration region are investigated. It was found that the influence of the former can neglect, but that of the latter is so prominent that the data fluctuate bitterly and linearity of the curve of the reduced viscosity vs. concentration (hsp/c^c) becomes too bad to obey the Huggins equation down to the extremely dilute region, despite the error of the flow times Dt 0.2s, which is permitted by the conventional method of viscosity measurement. Through strict mathematical analyses, it was found that the error (E) of the reduced viscosity is in proportion and inverse proportion to Dt and concentration c, respectively. So the less the concentration, the more the error is. Consequently, a lowest concentration limit cL corresponding to given experimental error may exist and it will be meaningless for further operation below cL because of the great fluctuation of the data. Therefore, it needs to seriously reconsider the application of the conventional method of Ubbelohde viscosity measurement in the extremely dilute polymer solution under traditional conditions because of the great influence of the experimental error.展开更多
Modified diphenyl oxide resin was synthesized by co-polymerization of unsaturated acid and diphenyl oxide derivants. And then modified bismaleimide resin and expoxide linear phenolic resin were added into modified dip...Modified diphenyl oxide resin was synthesized by co-polymerization of unsaturated acid and diphenyl oxide derivants. And then modified bismaleimide resin and expoxide linear phenolic resin were added into modified diphenyl oxide resin to co-polymerize and modify once more. The system was applied in composites. Their properties were investigated and found that they met the requirements as a heat-resisting adhesive.展开更多
Nanotechnology and its applications to medicine,known as nanomedicine,involve a wide use of nanomaterials to stimulate and guide the regenerative properties of cells.In particular,tissue regeneration can be promoted b...Nanotechnology and its applications to medicine,known as nanomedicine,involve a wide use of nanomaterials to stimulate and guide the regenerative properties of cells.In particular,tissue regeneration can be promoted by enabling a controlled release of therapeutic agents,which can be done using nanoparticles.In this review article,the fundamentals of tissue regeneration are discussed,focusing on epithelial tissue,to demonstrate the importance of delivering therapeutic agents in an efficient,sustained and localized manner.Then,the methods for synthesizing metallic and polymeric nanoparticles are described.While polymeric nanoparticles can be loaded with an agent during synthesis,metallic nanoparticles must first be synthesized to later interact with therapeutic agents.This interaction can be fine-tuned by functionalizing metallic nanoparticles with organic molecules,which results in a more controlled attachment.This review highlights the importance of choosing the appropriate method of synthesis and functionalization,which must be designed considering both the type of tissue to regenerate and the nature of the agent to be transported.展开更多
基金ItemSponsored by National Natural Science Foundation of China (50334020) National Key Fundamental Research andDevelopment Project of China (2000026300)
文摘Through thermal test, cold state experiment, analysis and simulation of thermal process, the gas flow distribution in pelletizing shaft furnace （PSF） was discussed. The results show that there are five flowing trends among them, the downward roasting gas and the upward cooling gas are the most unsteady, which influence flow distribution greatly. Among the operating parameters, the ratio of inflow is a key factor affecting the flow distribution. The roasting and cooling gases will entirely flow into the roasting zone and internal vertical air channels （IVAC）, respectively, if the ratio of inflow is critical. From such a critical operating condition increasing roasting gas flow or decreasing cooling gas flow, the roasting gas starts flowing downwards so as to enter the inside of IVAC the greater the ratio of inflow, the larger the downward flowrate. Among constructional parameters, the width of roasting zone b1, width of IVAC b2 and width of cooling zone b3, and the height of roasting zone h1, height of soaking zone h2 and height of cooling zone hs are the main factors affecting flow distribution. In case the ratio of b2/b3, or h3/h2, or h1/h2 is increased, the upward cooling gas tends to decrease while the downward roasting gas tends to increase with a gradual decrease in the ratio of inflow.
文摘The influences of both the volume of PS/toluene solution in the Ubbelohde viscometer and the precision of the time measuring on the viscosity behavior in dilute and extremely dilute concentration region are investigated. It was found that the influence of the former can neglect, but that of the latter is so prominent that the data fluctuate bitterly and linearity of the curve of the reduced viscosity vs. concentration (hsp/c^c) becomes too bad to obey the Huggins equation down to the extremely dilute region, despite the error of the flow times Dt 0.2s, which is permitted by the conventional method of viscosity measurement. Through strict mathematical analyses, it was found that the error (E) of the reduced viscosity is in proportion and inverse proportion to Dt and concentration c, respectively. So the less the concentration, the more the error is. Consequently, a lowest concentration limit cL corresponding to given experimental error may exist and it will be meaningless for further operation below cL because of the great fluctuation of the data. Therefore, it needs to seriously reconsider the application of the conventional method of Ubbelohde viscosity measurement in the extremely dilute polymer solution under traditional conditions because of the great influence of the experimental error.
文摘Modified diphenyl oxide resin was synthesized by co-polymerization of unsaturated acid and diphenyl oxide derivants. And then modified bismaleimide resin and expoxide linear phenolic resin were added into modified diphenyl oxide resin to co-polymerize and modify once more. The system was applied in composites. Their properties were investigated and found that they met the requirements as a heat-resisting adhesive.
基金funded by FONDECYT-CONCYTEC(155-2015-FONDECYT)the partnership Cleveland Clinic-Universidad de Ingenieria y Tecnologia-UTEC。
文摘Nanotechnology and its applications to medicine,known as nanomedicine,involve a wide use of nanomaterials to stimulate and guide the regenerative properties of cells.In particular,tissue regeneration can be promoted by enabling a controlled release of therapeutic agents,which can be done using nanoparticles.In this review article,the fundamentals of tissue regeneration are discussed,focusing on epithelial tissue,to demonstrate the importance of delivering therapeutic agents in an efficient,sustained and localized manner.Then,the methods for synthesizing metallic and polymeric nanoparticles are described.While polymeric nanoparticles can be loaded with an agent during synthesis,metallic nanoparticles must first be synthesized to later interact with therapeutic agents.This interaction can be fine-tuned by functionalizing metallic nanoparticles with organic molecules,which results in a more controlled attachment.This review highlights the importance of choosing the appropriate method of synthesis and functionalization,which must be designed considering both the type of tissue to regenerate and the nature of the agent to be transported.
