ZSM-5 zeolite was rapidly synthesized in system containing ethylenediamine from the initial gel: (5?8) Na2O: 44 EDA:Al2O3:100 SiO2:4000 H2O. The crystals were lath-shaped. The effect of pretreatment and alkalinity on...ZSM-5 zeolite was rapidly synthesized in system containing ethylenediamine from the initial gel: (5?8) Na2O: 44 EDA:Al2O3:100 SiO2:4000 H2O. The crystals were lath-shaped. The effect of pretreatment and alkalinity on crystallinity was investigated. The pretreatment of silicate source can cut down the crystallization time. Tuning the system alkalinity and controlling crystallization time can ensure forming of pure crystal.展开更多
The effects of magnetic field intensity, roasting temperature and roasting time on digestion rate and settling performance of bauxite with different iron contents were investigated systematically. The results indicate...The effects of magnetic field intensity, roasting temperature and roasting time on digestion rate and settling performance of bauxite with different iron contents were investigated systematically. The results indicate that such magnetic treatment can profoundly change the microstructure and digestion performance of bauxite. For the two samples carrying different iron contents, phase transformation of the aluminum oxide phase proceeds faster in the high iron bauxite than the low one. The optimal pretreatment conditions of low iron bauxite are roasting temperature 550 ℃ and magnetic field intensity 6 T, while for high iron bauxite are 500 ℃ and 9 T. The digestion rate of alumina can reach 95% and 92% at digestion temperature of 190 ℃ and 250 ℃. The settling performances of roasted ore by intense magnetic field after digestion are enhanced through pretreatment.展开更多
A parallel hybrid linear solver based on the Schur complement method has the potential to balance the robustness of direct solvers with the efficiency of preconditioned iterative solvers.However,when solving large-sca...A parallel hybrid linear solver based on the Schur complement method has the potential to balance the robustness of direct solvers with the efficiency of preconditioned iterative solvers.However,when solving large-scale highly-indefinite linear systems,this hybrid solver often suffers from either slow convergence or large memory requirements to solve the Schur complement systems.To overcome this challenge,we in this paper discuss techniques to preprocess the Schur complement systems in parallel. Numerical results of solving large-scale highly-indefinite linear systems from various applications demonstrate that these techniques improve the reliability and performance of the hybrid solver and enable efficient solutions of these linear systems on hundreds of processors,which was previously infeasible using existing state-of-the-art solvers.展开更多
基金Project (No. 29976036) supported by the National Natural Science Foundation of China
文摘ZSM-5 zeolite was rapidly synthesized in system containing ethylenediamine from the initial gel: (5?8) Na2O: 44 EDA:Al2O3:100 SiO2:4000 H2O. The crystals were lath-shaped. The effect of pretreatment and alkalinity on crystallinity was investigated. The pretreatment of silicate source can cut down the crystallization time. Tuning the system alkalinity and controlling crystallization time can ensure forming of pure crystal.
基金Projects(U1202274,51004033,51204040,50974035)supported by the National Natural Science Foundation of ChinaProjects(2010AA03A405,2012AA062303)supported by the National High Technology Research and Development Program(863 Prograam)of ChinaProject(N100302005)supported by the Fundamental Research Funds for the Central Universities,China
文摘The effects of magnetic field intensity, roasting temperature and roasting time on digestion rate and settling performance of bauxite with different iron contents were investigated systematically. The results indicate that such magnetic treatment can profoundly change the microstructure and digestion performance of bauxite. For the two samples carrying different iron contents, phase transformation of the aluminum oxide phase proceeds faster in the high iron bauxite than the low one. The optimal pretreatment conditions of low iron bauxite are roasting temperature 550 ℃ and magnetic field intensity 6 T, while for high iron bauxite are 500 ℃ and 9 T. The digestion rate of alumina can reach 95% and 92% at digestion temperature of 190 ℃ and 250 ℃. The settling performances of roasted ore by intense magnetic field after digestion are enhanced through pretreatment.
基金supported in part by the Director,Office of Science,Office of Advanced Scientific Computing Research,of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231.
文摘A parallel hybrid linear solver based on the Schur complement method has the potential to balance the robustness of direct solvers with the efficiency of preconditioned iterative solvers.However,when solving large-scale highly-indefinite linear systems,this hybrid solver often suffers from either slow convergence or large memory requirements to solve the Schur complement systems.To overcome this challenge,we in this paper discuss techniques to preprocess the Schur complement systems in parallel. Numerical results of solving large-scale highly-indefinite linear systems from various applications demonstrate that these techniques improve the reliability and performance of the hybrid solver and enable efficient solutions of these linear systems on hundreds of processors,which was previously infeasible using existing state-of-the-art solvers.