The mode selectivity of the H+CH_(3)D→H_(2)+CH_(2)D reaction was studied using a recently developed ten-dimensional time-dependent wave packet method.The reaction dynamics are studied for the reactant CH_(3)D initial...The mode selectivity of the H+CH_(3)D→H_(2)+CH_(2)D reaction was studied using a recently developed ten-dimensional time-dependent wave packet method.The reaction dynamics are studied for the reactant CH_(3)D initially from the ground state,the CH_(3) symmetry and asymmetry stretching excitation,the CD stretching excitation and the fundamental and the first overtone of the CH_(3) bending mode.The calculated reaction probabilities show that exciting either of the CH_(3) stretching modes enhances the reactivity in the collision energy range below 1.0 eV,while the CD stretching excitation does not obviously prompt the reaction.Fundamental CH_(3) bending excitation has nearly no effect on promoting reactivity.However,a significant enhancement is observed for the first overtone excitation of the CH_(3) bending mode,resulting from the Fermi resonance between the fundamental state of the CH_(3) symmetry stretching mode and the first overtone state of the CH_(3) bending mode.展开更多
In this article, we calculate the branching ratios of B→K0^＊ （1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar mes...In this article, we calculate the branching ratios of B→K0^＊ （1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar meson spectrum. We find that （i） The leading order pQCD predictions for the branching ratio Br（B^＋→K^＋K0^＊（1430）^0）are in good agreement with the experimental upper limit in both scenarios, while the pQCD predictions for other considered B→K0^＊（1430）K decay modes are also presented and will be tested by the LHC experiments; （ii） The annihilation contributions play an important role in these considered decays, for B^0→K0^＊（1430）^±K^± decays,for example,which are found to be （1-4）×10^-6.展开更多
Inspired by the controversy over tensile deformation modes of single-crystalline 〈110〉/{111} Au nanowires, we investigated the dependency of the deformation mode on diameters of nanowires using the molecular dynamic...Inspired by the controversy over tensile deformation modes of single-crystalline 〈110〉/{111} Au nanowires, we investigated the dependency of the deformation mode on diameters of nanowires using the molecular dynamics technique. A new criterion for assessing the preferred deformation mode-slip or twin propagation--of nanowires as a function of nanowire diameter is presented. The results demonstrate the size-dependent transition, from superplastic deformation mediated by twin propagation to the rupture by localized slips in deformed region as the nanowire diameter decreases. Moreover, the criterion was successfully applied to explain the superplastic deformation of Cu nanowires.展开更多
Due to the coexistence and coupling of continuous variables and discrete events, the vehicle height adjustment process of electronic air suspension system can be regarded as a typical hybrid system. Therefore, the hyb...Due to the coexistence and coupling of continuous variables and discrete events, the vehicle height adjustment process of electronic air suspension system can be regarded as a typical hybrid system. Therefore, the hybrid system theory was applied to design a novel vehicle height control strategy in this paper. A nonlinear mechanism model of the vehicle height adjustment system was established based on vehicle system dynamics and thermodynamic theory for variable-mass gas charge/discharge system. In order to model both the continuous/discrete dynamics of vehicle height adjustment process and the on-off statuses switching of solenoid valves, the framework of mixed logical dynamical(MLD) modelling was used. On the basis of the vehicle height adjustment control strategy, the MLD model of the adjustment process was built by introducing auxiliary logical variables and auxiliary continuous variables. Then, the co-simulation of the nonlinear mechanism model and the MLD model was conducted based on the compiling of HYSDEL. The simulation and experimental results show that the proposed control strategy can not only adjust the vehicle height effectively, but also achieve the on-off statuses direct control of solenoid valves.展开更多
基金supported by the National Natural Science Foundation of China(No.21773297,No.21973108,and No.21921004 to Minghui Yang,No.21973109 to Hongwei Song)。
文摘The mode selectivity of the H+CH_(3)D→H_(2)+CH_(2)D reaction was studied using a recently developed ten-dimensional time-dependent wave packet method.The reaction dynamics are studied for the reactant CH_(3)D initially from the ground state,the CH_(3) symmetry and asymmetry stretching excitation,the CD stretching excitation and the fundamental and the first overtone of the CH_(3) bending mode.The calculated reaction probabilities show that exciting either of the CH_(3) stretching modes enhances the reactivity in the collision energy range below 1.0 eV,while the CD stretching excitation does not obviously prompt the reaction.Fundamental CH_(3) bending excitation has nearly no effect on promoting reactivity.However,a significant enhancement is observed for the first overtone excitation of the CH_(3) bending mode,resulting from the Fermi resonance between the fundamental state of the CH_(3) symmetry stretching mode and the first overtone state of the CH_(3) bending mode.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10575052, 10605012, and 10735080
文摘In this article, we calculate the branching ratios of B→K0^＊ （1430）K decays by employing the pertur-bative QCD （pQCD） approach at leading order. We perform the evaluations in the two scenarios for the scalar meson spectrum. We find that （i） The leading order pQCD predictions for the branching ratio Br（B^＋→K^＋K0^＊（1430）^0）are in good agreement with the experimental upper limit in both scenarios, while the pQCD predictions for other considered B→K0^＊（1430）K decay modes are also presented and will be tested by the LHC experiments; （ii） The annihilation contributions play an important role in these considered decays, for B^0→K0^＊（1430）^±K^± decays,for example,which are found to be （1-4）×10^-6.
文摘Inspired by the controversy over tensile deformation modes of single-crystalline 〈110〉/{111} Au nanowires, we investigated the dependency of the deformation mode on diameters of nanowires using the molecular dynamics technique. A new criterion for assessing the preferred deformation mode-slip or twin propagation--of nanowires as a function of nanowire diameter is presented. The results demonstrate the size-dependent transition, from superplastic deformation mediated by twin propagation to the rupture by localized slips in deformed region as the nanowire diameter decreases. Moreover, the criterion was successfully applied to explain the superplastic deformation of Cu nanowires.
基金supported by the National Natural Science Foundation of China(Grant Nos.51375212 and 51105177)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20133227130001)the China Postdoctoral Science Foundation(Grant No.2014M551518)
文摘Due to the coexistence and coupling of continuous variables and discrete events, the vehicle height adjustment process of electronic air suspension system can be regarded as a typical hybrid system. Therefore, the hybrid system theory was applied to design a novel vehicle height control strategy in this paper. A nonlinear mechanism model of the vehicle height adjustment system was established based on vehicle system dynamics and thermodynamic theory for variable-mass gas charge/discharge system. In order to model both the continuous/discrete dynamics of vehicle height adjustment process and the on-off statuses switching of solenoid valves, the framework of mixed logical dynamical(MLD) modelling was used. On the basis of the vehicle height adjustment control strategy, the MLD model of the adjustment process was built by introducing auxiliary logical variables and auxiliary continuous variables. Then, the co-simulation of the nonlinear mechanism model and the MLD model was conducted based on the compiling of HYSDEL. The simulation and experimental results show that the proposed control strategy can not only adjust the vehicle height effectively, but also achieve the on-off statuses direct control of solenoid valves.
