To gain superior computational efficiency, it might be necessary to change the underlying philosophy of the simplex method. In this paper, we propose a Phase-1 method along this line. We relax not only the conventiona...To gain superior computational efficiency, it might be necessary to change the underlying philosophy of the simplex method. In this paper, we propose a Phase-1 method along this line. We relax not only the conventional condition that some function value increases monotonically, but also the condition that all feasible variables remain feasible after basis change in Phase-1. That is, taking a purely combinatorial approach to achieving feasibility. This enables us to get rid of ratio test in pivoting, reducing computational cost per iteration to a large extent. Numerical results on a group of problems are encouraging.展开更多
This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant i...This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant interaction, which is important in view of decoherence. Furthermore, the scheme is feasible based on current technologies.展开更多
环己酮肟气相Beckmann重排反应RBS-1催化剂在高温反应时易失活,导致催化剂费用居高不下。为提高技术经济性,实现失活催化剂性能的高效恢复,系统研究RBS-1催化剂失活机理、再生手段及催化性能。采用N_(2)物理吸附-脱附技术考察催化剂失...环己酮肟气相Beckmann重排反应RBS-1催化剂在高温反应时易失活,导致催化剂费用居高不下。为提高技术经济性,实现失活催化剂性能的高效恢复,系统研究RBS-1催化剂失活机理、再生手段及催化性能。采用N_(2)物理吸附-脱附技术考察催化剂失活前后与再生前后的比表面积及孔结构变化,并结合XRD、FT-IR和^(29)Si MAS NMR表征技术探讨了RBS-1催化剂在失活与再生过程中活性中心的演变规律。研究发现,失活RBS-1催化剂物相结构保持完好,但BET比表面积和孔体积均有明显降低,说明催化剂失活主要为积炭覆盖催化剂活性位点并堵塞孔道所致。针对积炭堵孔导致的催化剂失活问题,采用烧炭、含氮化合物改性处理构建巢式硅羟基活性位点等手段对失活催化剂进行再生研究。结果表明,在530℃下烧炭能将催化剂表面及孔道内的大部分积炭烧除,催化剂性能可恢复90%以上;对脱炭后的催化剂进一步改性处理,最优催化剂性能可恢复98%以上。展开更多
文摘To gain superior computational efficiency, it might be necessary to change the underlying philosophy of the simplex method. In this paper, we propose a Phase-1 method along this line. We relax not only the conventional condition that some function value increases monotonically, but also the condition that all feasible variables remain feasible after basis change in Phase-1. That is, taking a purely combinatorial approach to achieving feasibility. This enables us to get rid of ratio test in pivoting, reducing computational cost per iteration to a large extent. Numerical results on a group of problems are encouraging.
基金Project supported by the National Natural Science Foundation of China(Grant Nos10574022 and 10575022)the Funds of the Natural Science of Fujian Province,China(Grant Nos Z0512006 and A0210014)
文摘This paper proposes a scheme for the implementation of 1→ 3 optimal phase-covariant quantum cloning with trapped ions. In the present protocol, the required time for the whole procedure is short due to the resonant interaction, which is important in view of decoherence. Furthermore, the scheme is feasible based on current technologies.
文摘环己酮肟气相Beckmann重排反应RBS-1催化剂在高温反应时易失活,导致催化剂费用居高不下。为提高技术经济性,实现失活催化剂性能的高效恢复,系统研究RBS-1催化剂失活机理、再生手段及催化性能。采用N_(2)物理吸附-脱附技术考察催化剂失活前后与再生前后的比表面积及孔结构变化,并结合XRD、FT-IR和^(29)Si MAS NMR表征技术探讨了RBS-1催化剂在失活与再生过程中活性中心的演变规律。研究发现,失活RBS-1催化剂物相结构保持完好,但BET比表面积和孔体积均有明显降低,说明催化剂失活主要为积炭覆盖催化剂活性位点并堵塞孔道所致。针对积炭堵孔导致的催化剂失活问题,采用烧炭、含氮化合物改性处理构建巢式硅羟基活性位点等手段对失活催化剂进行再生研究。结果表明,在530℃下烧炭能将催化剂表面及孔道内的大部分积炭烧除,催化剂性能可恢复90%以上;对脱炭后的催化剂进一步改性处理,最优催化剂性能可恢复98%以上。
