Currently,artificial-membrane lungs consist of thousands of hollow fiber membranes where blood flows around the fibers and gas flows inside the fibers,achieving diffusive gas exchange.At both ends of the fibers,the in...Currently,artificial-membrane lungs consist of thousands of hollow fiber membranes where blood flows around the fibers and gas flows inside the fibers,achieving diffusive gas exchange.At both ends of the fibers,the interspaces between the hollow fiber membranes and the plastic housing are filled with glue to separate the gas from the blood phase.During a uniaxial centrifugation process,the glue forms the“potting.”The shape of the cured potting is then determined by the centrifugation process,limiting design possibilities and leading to unfavorable stagnation zones associated with blood clotting.In this study,a new multiaxial centrifugation process was developed,expanding the possible shapes of the potting and allowing for completely new module designs with potentially superior blood flow guidance within the potting margins.Two-phase simulations of the process in conceptual artificial lungs were performed to explore the possibilities of a biaxial centrifugation process and determine suitable parameter sets.A corresponding biaxial centrifugation setup was built to prove feasibility and experimentally validate four conceptual designs,resulting in good agreement with the simulations.In summary,this study shows the feasibility of a multiaxial centrifugation process allowing greater variety in potting shapes,eliminating inefficient stagnation zones and more favorable blood flow conditions in artificial lungs.展开更多
The synthesis of chiral dimeric Salen ligand 5, 5＇-methylene-di-[（R, R ）-｜ N-（3-tert-butylsalicylidine）-N＇- （ 3＇, 5＇-di- tert-butylsalicylidene） ｜ - 1, 2-cyclohexanediamine ] which using 2-tert-butylphenol...The synthesis of chiral dimeric Salen ligand 5, 5＇-methylene-di-[（R, R ）-｜ N-（3-tert-butylsalicylidine）-N＇- （ 3＇, 5＇-di- tert-butylsalicylidene） ｜ - 1, 2-cyclohexanediamine ] which using 2-tert-butylphenol as starting material is reported. This compound reacts with cobalt （Ⅱ） acetate and then oxidized by air to give dimeric Salen catalyst 5 in this paper, which catalyzes the hydrolytic kinetic resolution （HKR） of racemic epichlorohydrin to afford biologically important chiral epoxides and diols. Ee values of diol up to 97 % were obtained, and the catalyst was recovered with no apparent loss.展开更多
文摘Currently,artificial-membrane lungs consist of thousands of hollow fiber membranes where blood flows around the fibers and gas flows inside the fibers,achieving diffusive gas exchange.At both ends of the fibers,the interspaces between the hollow fiber membranes and the plastic housing are filled with glue to separate the gas from the blood phase.During a uniaxial centrifugation process,the glue forms the“potting.”The shape of the cured potting is then determined by the centrifugation process,limiting design possibilities and leading to unfavorable stagnation zones associated with blood clotting.In this study,a new multiaxial centrifugation process was developed,expanding the possible shapes of the potting and allowing for completely new module designs with potentially superior blood flow guidance within the potting margins.Two-phase simulations of the process in conceptual artificial lungs were performed to explore the possibilities of a biaxial centrifugation process and determine suitable parameter sets.A corresponding biaxial centrifugation setup was built to prove feasibility and experimentally validate four conceptual designs,resulting in good agreement with the simulations.In summary,this study shows the feasibility of a multiaxial centrifugation process allowing greater variety in potting shapes,eliminating inefficient stagnation zones and more favorable blood flow conditions in artificial lungs.
基金Sponsored by the Beijing Municipal Science & Technology Commission Project (20070539022)
文摘The synthesis of chiral dimeric Salen ligand 5, 5＇-methylene-di-[（R, R ）-｜ N-（3-tert-butylsalicylidine）-N＇- （ 3＇, 5＇-di- tert-butylsalicylidene） ｜ - 1, 2-cyclohexanediamine ] which using 2-tert-butylphenol as starting material is reported. This compound reacts with cobalt （Ⅱ） acetate and then oxidized by air to give dimeric Salen catalyst 5 in this paper, which catalyzes the hydrolytic kinetic resolution （HKR） of racemic epichlorohydrin to afford biologically important chiral epoxides and diols. Ee values of diol up to 97 % were obtained, and the catalyst was recovered with no apparent loss.
