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Preparation and desulfurization activity of nano-CeO_2/γ-Al_2O_3 catalysts

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Rare Metals 2018年第7期37卷 554-560页

作者： Qi Yang Hui Hu shan-shan Wang School of Environment Science and Engineering Huazhong University of Science and Technology Department of Urban Construction Wuchang Shouyi University Wuhan Zuoling New Town Development and Investment Co. Ltd.

γ-A12O3-supported CeO2 catalysts were pre- pared by microemulsion and impregnation methods and characterized by X-ray diffraction （XRD） and scanning electron microscope （SEM） techniques. At the same time, the desulfurization activity of catalysts was investigated. The results show that nanoscale active substances and a high desulfurization effect are achieved by microemulsion, exhibiting a significant dominance compared with traditional impregnation method. The optimal preparation condition is temperature of 30 ℃ and ratio of [H20]/[surface active agent] of 7 with slow demulsification. The activated catalysts still keep high and stable desulfurization activity during a wide temperature range of 450-600 ℃. Among a series of prepared catalysts, the desulfurization rate of 6CeOz/γ-A1203 is the highest, reaching up to 80 % when temperature is higher than 550℃. The catalytic reduction mechanism of SO2 over nano-CeOz/γ-A1203 follows redox mechanism.

关键词： Nano-CeO2/γ-Al2O3 Microemulsion Catalyst Desulfurization

Existence and multiplicity results for nonlinear Schrodinger-Poisson equation with general potential

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Frontiers of Mathematics in China 2020年第6期15卷 1189-1200页

作者： Yuan shan School of Statistics and Mathematics Nanjing Audit UniversityNanjing 210029China

This paper is concerned with the Schrodinger-Poisson equation -△u+V(x)u+Ф(x)u=f(x,u),x∈R^(3),-△Ф=u^(2),lim|x|→+∞Ф(x)=*** certain hypotheses on V and a general spectral assumption,the existence and multiplicity... 详细信息

关键词： Schrodinger-Poisson equation Morse index variational method

Parametrized post-Newtonian secular transit timing variations for exoplanets

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Research in Astronomy and Astrophysics 2013年第10期13卷 1231-1239页

作者： shan-shan Zhao Yi Xie Department of Astronomy Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education

Ground-based and space-borne observatories used for studying exoplanet transits now and in the future will considerably increase the number of exoplanets known from transit data and the precision of the measured times of transit *** in the transit times can not only be used to infer the presence of additional planets,but might also provide opportunities to test the general theory of relativity in these *** build a framework for these possible tests,we extend previous studies on the observability of the general relativistic precessions of periastron in transiting exoplanets to variations in secular transit timing under parametrized post-Newtonian *** find that if one can measure the difference between observed and predicted variations of general relativistic secular transit timing to 1 s yr-1in a transiting exoplanet system with a Sun-like mass,a period of;day and a relatively small eccentricity of;.1,general relativity will be tested to the level of;%.

关键词： gravitation celestial mechanics planetary systems

Influence of Isotope Effects on Product Polarizations of N(~2D)+D_2, N(~2D)+H_2 and N(~2D)+HD Reactive Systems

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Chemical Research in Chinese Universities 2012年第5期28卷 897-902页

作者： NIE shan-shan CHU Tian-shu State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023P.R.China Institute for Computational Sciences and Engineering Laboratory of New Fiber Materials and Modern Textilethe Growing Base for State Key LaboratoryQingdao UniversityQingdao 266071P.R.China

To figure out the influence of isotope effect on product polarizations of the N（2D）＋D2 reactive system and its isotope variants, quasi-classical trajectory（QCT） calculation was performed on Ho＇s potential energy surface（PES） of 2A″ state. Product polarizations such as product distributions of P（θr）, P（φr） and P（θr,φr）, as well as the generalized polarization-dependent differential cross sections（PDDCSs） were discussed and compared in detail among the four product channels of the title reactions. Both the intermolecular and intramolecular isotope effects were proved to be influential on product polarizations.

关键词： Isotope effect Product polarization Quasi-classical trajectory calculation Potential energy surface

Novel approach for determining the optimal axial preload of a simulating rotary table spindle system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 812-817页

作者： shan Xiao-biao XIE Tao CHEN Wei-shan School of Mechatronics Engineering Harbin Institute of Technology Harbin 15001 China

This paper presents a new theoretical model to determine the optimal axial preload of a spindle system, for challenging the traditional method which relies heavily on experience of engineers. The axial preloading stiffness was treated as the sum of the spindle modal stiffness and the framework elastic stiffness, based on a novel concept that magnitude of preloads can be controlled by measuring the resonant frequency of a spindle system. By employing an example of a certain type of aircraft simulating rotary table, the modal stiffness was measured on the Agilent 35670A Dynamic Signal Analyzer by experimental modal analysis. The equivalent elastic stiffness was simulated by both finite element analysis in ANSYS? and a curve fitting in MATLAB?. Results showed that the static preloading stiffness of the spindle was 7.2125×107 N/m, and that the optimal preloading force was 120.0848 N. Practical application proved the feasibility of our method.

关键词： Three-axis simulating rotary table Axial position preload Stiffness Experimental modal analysis Finite elementanalysis

Creep crack growth in a Cr-Mo-V type steel: experimental observation and prediction

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Acta Metallurgica Sinica(English Letters) 2011年第2期24卷 81-91页

作者： shan-Tung TU Key Laboratory of Safety Science of Pressurized System Ministry of Education School of Mechanical and Power Engineering East China University of Science and Technology

In this study, the creep crack growth （CCG） properties and fracture mechanism of a Cr-Mo-V steel at 566 C in compact tension （CT） specimens were investigated, and the CCG rate was predicted by using the NSW model. The results show that the CCG rate measured by CT specimens is much lower than that predicted by the NSW model under plane-strain state. This means that the NSW model prediction for the CCG rate of the steel is over-conservative. In addition, the CCG rate da/dt versus C measured by the experiments shows the piecewise linear relation on log-log scale instead of a single linear relation predicted by the NSW model. The main reasons for these results are that the actual creep fracture mechanism of the steel and the actual creep crack tip stress field in the CT specimens have not been fully captured in the NSW model. The experimental observation shows that the creep crack propagates in a discontinuous way （step by step） at meso-scale, and the cracks at micro-scale are usually formed by the growth and coalescence of voids on grain boundaries. The NSW model based on the creep ductility exhaustion approach may not correctly describe this creep fracture process. In addition, the opening stress and triaxial stress ahead of crack tips calculated by three-dimensional finite element method is lower than those predicted by the HRR stress field which is used in the NSW model under plane-strain state. The use of the high HRR stress field will cause high CCG rates. The change in the creep fracture mechanism at micro-scale in different ranges of C may cause the piecewise linear relation between the da/dt and C . Therefore, it is necessary to study the actual CCG mechanism in a wide range of C and the actual creep crack tip stress field to establish accurate CCG prediction models.

关键词： Creep crack growth Prediction NSW model Fracture mechanism Finite element method

Creep behavior of plasma sprayed NiCr and NiCrAl coating-based systems

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Acta Metallurgica Sinica(English Letters) 2011年第3期24卷 183-189页

作者： shan-Tung TU Key Laboratory of Safety Science of Pressurized System Ministry of EducationEast China University of Science and Technology

The creep behavior of the plasma sprayed NiCr and NiCrA1 coating/Nickel alloy 690 substrate systems at 1033 K was investigated. Results showed that there was almost no difference in the creep lives between the NiCr and NiCrA1 coated specimens at a given stress level, since the contents of Cr used in the NiCr and NiCrA1 powders are almost same. The relationship between the minimum creep rate and the applied stress followed the well-known Norton＇s power law, εmin=Aσ^n, with the values of A=2.66×10^-16 MPa^-n·h^-1 and n=6.48. The relation between the applied stress and time to rupture of the coated specimens can be estimated by using Larson-Miller equation. The θ projection method can be used to accurately characterize the creep behavior of the coated specimens.

关键词： Creep Coating θ projection method Minimum creep strainrate

危险预知训练模式结合密室逃脱教学在儿科急诊护士培训中的应用

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卫生职业教育 2025年第1期43卷 143-145页

作者：王珍朱杉华中科技大学同济医学院附属同济医院湖北武汉430030

目的探讨在儿科急诊护士培训中,危险预知训练模式结合密室逃脱教学的实践效果。方法选取湖北省武汉市某三甲医院2023年1—12月儿科急诊护士46人作为研究对象,随机分为对照组与研究组,分别实施常规培训模式、危险预知训练模式结合密室逃... 详细信息

目的探讨在儿科急诊护士培训中,危险预知训练模式结合密室逃脱教学的实践效果。方法选取湖北省武汉市某三甲医院2023年1—12月儿科急诊护士46人作为研究对象,随机分为对照组与研究组,分别实施常规培训模式、危险预知训练模式结合密室逃脱教学模式,对比两组考核成绩、应急能力、评判性思维能力与风险识别能力。结果研究组理论和急救技能考核成绩及应急能力、评判性思维能力、护理风险识别能力均优于对照组,差异有统计学意义(P<0.05)。结论危险预知训练模式结合密室逃脱教学应用于儿科急诊护士培训中效果较好,能有效提升护士的理论和急救技能水平及综合能力,值得推广。

关键词：危险预知训练模式密室逃脱教学模式儿科急诊护士

Predictive Control with Velocity Observer for Cushion Robot Based on PSO for Path Planning

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Journal of Systems Science & Complexity 2020年第4期33卷 988-1011页

作者： SUN Ping shan Rui School of Information Science and Engineering Shenyang University of TechnologyShenyang 110870China

This paper proposes a novel model predictive control method with velocity estimation simultaneously constraining trajectory and velocity tracking errors for a cushion robot. The authors investigated a path planning method using improved particle swarm optimization(PSO) combined with Dijkstra’s algorithm and obtained a real-time desired optimal motion path for obstacle *** authors designed a velocity observer to estimate the unmeasurable speed, while the asymptotic stability of the observer error system was established. A predictive controller with error-constrained performance was derived by solving a quadratic programming problem with incremental control. Simulation and experimental results confirm the effectiveness of the proposed method and verify that the error constraints adopted in the cushion robot provide safe motion while avoiding obstacles.

关键词： robot Robot Velocity