CO2is the main greenhouse gas which causes global climatic changes on larger scale. Many techniques have been utilised to capture CO2. Membrane gas separation is a fast growing CO2 capture technique, particularly gas ...CO2is the main greenhouse gas which causes global climatic changes on larger scale. Many techniques have been utilised to capture CO2. Membrane gas separation is a fast growing CO2 capture technique, particularly gas separation by composite membranes. The separation of CO2 by a membrane is not just a process to physically sieve out of CO2 through the controlled membrane pore size. It mainly depends upon diffusion and solubility of gases, particularly for composite dense membranes. The blended components in composite membranes have a high capability to adsorb CO2. The adsorption kinetics of the gases may directly affect diffusion and solubility. In this study, we have investigated the adsorption behaviour of CO2 in pure and composite membranes to explore the complete understanding of diffusion and solubility of CO2 through membranes. Pure cellulose acetate(CA) and cellulose acetatetitania nanoparticle(CA-TiO2) composite membranes were fabricated and characterised using SEM and FTIR analysis. The results indicated that the blended CA-TiO2 membrane adsorbed more quantity of CO2 gas as compared to pure CA membrane. The high CO2 adsorption capacity may enhance the diffusion and solubility of CO2 in the CA-TiO2 composite membrane, which results in a better CO2 separation. The experimental data was modelled by Pseudo first-order, pseudo second order and intra particle diffusion models.According to correlation factor R2, the Pseudo second order model was fitted well with experimental data. The intra particle diffusion model revealed that adsorption in dense membranes was not solely consisting of intra particle diffusion.展开更多
Digital Earth is an information expression of the real Earth,and is a new way of understanding the Earth in the twenty-first century.This paper introduces a Digital Earth Prototype System(DEPS)developed at the Chinese...Digital Earth is an information expression of the real Earth,and is a new way of understanding the Earth in the twenty-first century.This paper introduces a Digital Earth Prototype System(DEPS)developed at the Chinese Academy of Sciences(CAS)and supported by the Knowledge Innovation Program of the Chinese Academy of Sciences.Discussions are made to the theoretical model and technical framework of the Digital Earth,and its related key technologies on spatial information processing,spatial data warehouse technology,virtual reality technology,high-performance and parallel computing.The DEPS consists of seven sub-systems including the spatial data,metadata,model database,Grid geoscience computing,spatial information database,maps service and virtual reality.Meanwhile,we developed a series of application systems such as the environment monitoring for the Olympic Games 2008 in Beijing,natural disasters evaluation,digital city,digital archeology,Asia regional aerosol and climate change.The DEPS/CAS displayed the application ability and potential of the Digital Earth in three levels:the global,national and regional.展开更多
This paper presents a bilinear log model,for predicting temperature-dependent ultimate strength of high-entropy alloys(HEAs)based on 21 HEA compositions.We consider the break temperature,Tbreak,introduced in the model...This paper presents a bilinear log model,for predicting temperature-dependent ultimate strength of high-entropy alloys(HEAs)based on 21 HEA compositions.We consider the break temperature,Tbreak,introduced in the model,an important parameter for design of materials with attractive high-temperature properties,one warranting inclusion in alloy specifications.For reliable operation,the operating temperature of alloys may need to stay below Tbreak.We introduce a technique of global optimization,one enabling concurrent optimization of model parameters over low-temperature and high-temperature regimes.Furthermore,we suggest a general framework for joint optimization of alloy properties,capable of accounting for physics-based dependencies,and show how a special case can be formulated to address the identification of HEAs offering attractive ultimate strength.We advocate for the selection of an optimization technique suitable for the problem at hand and the data available,and for properly accounting for the underlying sources of variations.展开更多
基金supported by Higher Education Commission (HEC) Pakistan
文摘CO2is the main greenhouse gas which causes global climatic changes on larger scale. Many techniques have been utilised to capture CO2. Membrane gas separation is a fast growing CO2 capture technique, particularly gas separation by composite membranes. The separation of CO2 by a membrane is not just a process to physically sieve out of CO2 through the controlled membrane pore size. It mainly depends upon diffusion and solubility of gases, particularly for composite dense membranes. The blended components in composite membranes have a high capability to adsorb CO2. The adsorption kinetics of the gases may directly affect diffusion and solubility. In this study, we have investigated the adsorption behaviour of CO2 in pure and composite membranes to explore the complete understanding of diffusion and solubility of CO2 through membranes. Pure cellulose acetate(CA) and cellulose acetatetitania nanoparticle(CA-TiO2) composite membranes were fabricated and characterised using SEM and FTIR analysis. The results indicated that the blended CA-TiO2 membrane adsorbed more quantity of CO2 gas as compared to pure CA membrane. The high CO2 adsorption capacity may enhance the diffusion and solubility of CO2 in the CA-TiO2 composite membrane, which results in a better CO2 separation. The experimental data was modelled by Pseudo first-order, pseudo second order and intra particle diffusion models.According to correlation factor R2, the Pseudo second order model was fitted well with experimental data. The intra particle diffusion model revealed that adsorption in dense membranes was not solely consisting of intra particle diffusion.
基金supported by National Basic Research Program of China(973 Program,NO.2009CB723906)the Knowledge Innovation Program of Chinese Academy of Sciences(NO.KKCX1-YW-01).
文摘Digital Earth is an information expression of the real Earth,and is a new way of understanding the Earth in the twenty-first century.This paper introduces a Digital Earth Prototype System(DEPS)developed at the Chinese Academy of Sciences(CAS)and supported by the Knowledge Innovation Program of the Chinese Academy of Sciences.Discussions are made to the theoretical model and technical framework of the Digital Earth,and its related key technologies on spatial information processing,spatial data warehouse technology,virtual reality technology,high-performance and parallel computing.The DEPS consists of seven sub-systems including the spatial data,metadata,model database,Grid geoscience computing,spatial information database,maps service and virtual reality.Meanwhile,we developed a series of application systems such as the environment monitoring for the Olympic Games 2008 in Beijing,natural disasters evaluation,digital city,digital archeology,Asia regional aerosol and climate change.The DEPS/CAS displayed the application ability and potential of the Digital Earth in three levels:the global,national and regional.
基金X.F.and P.K.L.very much appreciate the support of the U.S.Army Research Office Project(W911NF-13-1-0438 and W911NF-19-2-0049)with the program managersDrs M.P.Bakas,S.N.Mathaudhu,and D.M.Stepp,as well as the support from the Bunch Fellowship.XF and PKL also would like to acknowledge funding from the State of Tennessee and Tennessee Higher Education Commission(THEC)through their support of the Center for Materials Processing(CMP).P.K.L.,furthermore,thanks the support from the National Science Foundation(DMR-1611180 and 1809640)with the program directors+1 种基金Drs J.Yang,G.Shiflet,and D.Farkas.B.S.very much appreciates the support from the National Science Foundation(IIP-1447395 and IIP-1632408)with the program directorsDr G.Larsen and R.Mehta,from the U.S.Air Force(FA864921P0754),with J.Evans as the program manager,and from the U.S.Navy(N6833521C0420),with Drs D.Shifler and J.Wolk as the program managers.M.C.G.acknowledges the support of the US Department of Energy’s Fossil Energy Crosscutting Technology Research Program.The authors also want to thank Dr.G.Tewksbury for bringing to their attention suspicious recordings of the US from the literature,which have prompted the data curation effort.
文摘This paper presents a bilinear log model,for predicting temperature-dependent ultimate strength of high-entropy alloys(HEAs)based on 21 HEA compositions.We consider the break temperature,Tbreak,introduced in the model,an important parameter for design of materials with attractive high-temperature properties,one warranting inclusion in alloy specifications.For reliable operation,the operating temperature of alloys may need to stay below Tbreak.We introduce a technique of global optimization,one enabling concurrent optimization of model parameters over low-temperature and high-temperature regimes.Furthermore,we suggest a general framework for joint optimization of alloy properties,capable of accounting for physics-based dependencies,and show how a special case can be formulated to address the identification of HEAs offering attractive ultimate strength.We advocate for the selection of an optimization technique suitable for the problem at hand and the data available,and for properly accounting for the underlying sources of variations.