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Potassium channel AKT1 is involved in the auxin-mediated root growth inhibition in Arabidopsis response to low K^+stress

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Journal of Integrative Plant Biology 2017年第12期59卷 895-909页

作者： Juan Li wei-hua Wu Yi Wang State Key Laboratory of Plant Physiology and Biochemistry(SKLPPB) College of Biological SciencesChina Agricultural UniversityBeijing 100193China

The changes in external K^＋ concentration affect plant root growth. However, the molecular mechanism for perceiving a K^＋ signal to modulate root growth remains unknown. It is hypothesized that the K^＋ channel AKTI is involved in low K^＋ sensing in the Arabidopsis root and subsequent regulation of root growth. Along with the decline of external K^＋ concentration, the primary root growth of wild-type plants was gradually inhibited. However, the primary root of the akt1 mutant could still grow under low K^＋（LK） conditions. Application of NAA inhibited akt1 root growth, but promoted wild-type root growth under LK conditions. By using the ProDR5：GFP and ProPIN1：PIN1-GFP lines, we found that LK treatment reduced auxin accumulation in wild-type root tips by degrading PIN1 proteins, which did not occur in the akt1 mutant. The LK-induced PIN1 degradation may be due to the inhibition of vesicle trafficking of PIN1 proteins. In conclusion, our findings indicate that AKT1 is required for an Arabidopsis response to changes in external K^＋, and subsequent regulation of K^＋-dependent root growth by modulating PINt degradation and auxin redistribution in the root.

关键词： Potassium channel AKT1 is involved in the auxin-mediated root growth inhibition in Arabidopsis response to low K stress LK Figure

Identification and Guaranteed Performance Control of Hammerstein Systems over Wireless Channels

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International Journal of Automation and computing 2016年第2期13卷 125-132页

作者： wei-hua Deng Kang Li Jing Deng College of Electrical Engineering Shanghai University of Electric Power School of Electronics Electrical Engineering and Computer ScienceQueen's University

The problems of identification and stabilization of a class of Hammerstein systems over a wireless network are investigated in this paper. A new approach for the proof of iterative identification is presented first. Then a guaranteed performance controller is designed to stabilize the system. The effectiveness of the proposed approach is demonstrated by numerical examples.

关键词： Identification guaranteed performance control model-based approach wireless network stochastic delay.

Catalytic reductive dechlorination of p-chlorophenol in water using Ni/Fe nanoscale particles

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Journal of Environmental Sciences 2007年第3期19卷 362-366页

作者： ZHANG wei-hua QUAN Xie ZHANG Zhuo-yong College of Urban and Environmental Sciences Northeast Normal University Changchun 130024 China School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116023 China College of Chemistry Inner Mongolia University for the Nationalities Tongliao 028043 China

Nanoscale bimetallic Ni/Fe particles were synthesized from the reaction of sodium borohydride （NaBH4） with reduction of Ni^2＋ and Fe^2＋ in aqueous solution. The obtained Ni/Fe particles were characterized by TEM （transmission electron microscope）, XRD （X-ray diffractometer）, and N2-BET. The dechlorination activity of the Ni/Fe was investigated using p-chlorophenol （p-CP） as a probe agent. Results demonstrated that the nanoscale Ni/Fe could effectively dechlorinate p-CP at relatively low metal to solution ratio of 0.4 g/L （Ni 5 wt%）. The target with initial concentration ofp-CP 0.625 mmol/L was dechlorinted completely in 60 rain under ambient temperature and pressure. Factors affecting dechlorination efficiency, including reaction temperature, pH, Ni loading percentage over Fe, and metal to solution ratio, were investigated. The possible mechanism of dechlorination ofp-CP was proposed and discussed. The pseudo-first- order reaction took place on the surface of the Ni/Fe bimetallic particles, and the activation energy of the dechlorination reaction was determined to be 21.2 kJ/mol at the temperature rang of 287-313 K.

关键词： Ni/Fe bimetal nanoscale particles catalytic reduction p-CP dechlorination

Multi-objective optimization design method of the high-speed train head

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第9期14卷 631-641页

作者： Meng-ge YU Ji-ye ZHANG wei-hua ZHANG State Key Laboratory of Traction Power Southwest Jiaotong University

With the continuous improvement of the train speed, the dynamic environment of trains turns out to be aerodynamic domination. Solving the aerodynamic problems has become one of the key factors of the high-speed train head design. Given that the aerodynamic drag is a significant factor that restrains train speed and energy conservation, reducing the aerodynamic drag is thus an important consideration of the high-speed train head design. However, the reduction of the aerodynamic drag may increase other aerodynamic forces (moments), possibly deteriorating the operational safety of the train. The multi-objective optimization design method of the high-speed train head was proposed in this paper, and the aerodynamic drag and load reduction factor were set to be optimization objectives. The automatic multi-objective optimization design of the high-speed train head can be achieved by integrating a series of procedures into the multi-objective optimization algorithm, such as the establishment of 3D parametric model, the aerodynamic mesh generation, the calculation of the flow field around the train, and the vehicle system dynamics. The correlation between the optimization objectives and optimization variables was analyzed to obtain the most important optimization variables, and a further analysis of the nonlinear relationship between the key optimization variables and the optimization objectives was obtained. After optimization, the aerodynamic drag of optimized train was reduced by up to 4.15%, and the load reduction factor was reduced by up to 1.72%.

关键词： High-speed train Multi-objective optimization Parametric model Aerodynamic drag Load reduction factor

Study on Nonuniform Deformation of Tailor Rolled Blank During Uniaxial Tension

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1198-1204页

作者： hua-wei Zhang Xiang-hua Liu Li-Zhong Liu Ping Hu Jia-Lu Wu School of Mechanical Engineering and Automation Northeastern University Research Institute of Science and Technology Northeastern University School of Automotive Engineering Dalian University of Technology

The deformation characteristics of tailor rolled blank （TRB） in the course of uniaxial tension were studied by means of analysis, test and simulation. The mechanical analytical model of TRB during uniaxial tension was set up, and the deformation formulae for the thinner side and for the thicker side were derived to quantify the deformation of TRB. On this basis, uniaxial tension tests on TRB and ordinary blanks （the thinner side and the thicker side of TRB） were conducted. Lagrange polynomial interpolation method was adopted to construct the stress-strain fields of unannealed and annealed TRBs for solving TRB material parameters, and then, uniaxial tension simulation on TRB was completed. Deformations and properties of unannealed TRB were compared with those of annealed TRB, and the thinner side and the thicker side were also compared. Finally, the research results were explained by metallurgical structure. The results show that nonuniform deformation happens in TRB during uniaxial tension, and the necking occurs on the thinner side. The agreement of analysis, test and simulation confirms the correctness of the analytical model and the deformation formulae. The findings of this paper can lay the foundation for the future study on TRB stamping formability and provide a way for TRB modeling.

关键词： Tailor rolled blank (TRB) Nonuniform deformation Uniaxial tension Annealing Metallographical

APPLICATION OF LYAPUNOV EXPONENT SPECTRUM IN PRESSURE FLUCTUATION OF DRAFT TUBE

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Journal of Hydrodynamics 2009年第6期21卷 856-860页

作者： WANG Li-ying ZHAO wei-guo wei De-hua College of Water Conservancy and Hydroelectric Power Hebei University of Engineering Handan 056021 China

The Lyapunov exponent spectrum is firstly applied in the analysis of pressure fluctuation of draft tube and calculated based on the time series of vibration in experiments for different situations. Results shows that the Lyapunov exponent spectrum varies with the setting of guide vane, So the Lyapunov exponent spectrum can be used to judge the pressure fluctuation of draft tube so as to timely adjust the setting of the guide vanes to reduce the damage caused by the vibration.

关键词： Lyapunov exponent spectrum pressure fluctuation setting of guide vanes

Crack defect of tailor rolled blank in deep drawing process

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Journal of Iron and Steel Research International 2018年第12期25卷 1237-1243页

作者： hua-wei Zhang Jia-lu Wu Xin-gang Wang School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819LiaoningChina

The deformation process of tailor rolled blank (TRB)is different from that of a monolithic blank as a result of the variable thickness in the rolling direction,and thus,the mechanism of the crack phenomenon needs to be further *** crack defect of TRB square box was studied by numerical simulation and stamping *** stress state of TRB square box was *** this basis,the forming characteristics of TRB square box were *** effects of blank size and blank holder force (BHF)on the thickness thinning of TRB were ***,the *** the crack defect for TRB square box was *** indicate that non-uniformity is the most prominent characteristic during forming of TRB square *** larger the blank size and BHF on the thinner side are,the more inclined TRB is to crack. Excessive BHF or insufficient BHF on the thicker side can also lead to the occurrence of the crack *** on the thinner side slightly greater than that on the thicker side (40 kN on the thinner side and 20 kN on the thicker side)is advantageous to restrict the excessive thickness thinning of TRB and acquire a better *** location inclined to crack for TRB square box is the round comer of the wall on the thinner side.

关键词： Tailor rolled blank Square box Crack Blank size Blank holder force

AN ANT COLONY ALGORITHM FOR YARD TRUCK SCHEDULING AND YARD LOCATION ASSIGNMENT PROBLEMS WITH PRECEDENCE CONSTRAINTS

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Journal of Systems Science and Systems Engineering 2013年第1期22卷 21-37页

作者： Zhaojie XUE Canrong ZHANG Lixin MIAO wei-hua LIN Research Center of Modern Logistics Tsinghua Campusthe University Town Systems and Industrial Engineering Department University of Arizona

This paper examines the yard truck scheduling,the yard location assignment for discharging containers,and the quay crane scheduling in container *** into account the practical situation,we paid special attention to the loading and discharging precedence relationships between containers in the quay crane operations.A Mixed Integer Program（MIP） model is constructed,and a two-stage heuristic algorithm is *** the first stage an Ant Colony Optimization（ACO） algorithm is employed to generate the yard location assignment for discharging *** the second stage,the integration of the yard truck scheduling and the quay crane scheduling is a flexible job shop problem,and an efficient greedy algorithm and a local search algorithm are proposed. Extensive numerical experiments are conducted to test the performance of the proposed algorithms.

关键词： Container terminal yard truck scheduling yard location assignment quay crane scheduling precedence constraints ant colony optimization

Potassium and phosphorus transport and signaling in plants

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Journal of Integrative Plant Biology 2021年第1期63卷 34-52页

作者： Yi Wang Yi-Fang Chen wei-hua Wu State Key Laboratory of Plant Physiology and Biochemistry(SKLPPB) College of Biological SciencesChina Agricultural UniversityBeijing 100193China

Nitrogen(N), potassium(K), and phosphorus(P) are essential macronutrients for plant growth and development, and their availability affects crop yield. Compared with N, the relatively low availability of K and P in soils limits crop production and thus threatens food security and agricultural sustainability. Improvement of plant nutrient utilization efficiency provides a potential route to overcome the effects of K and P deficiencies. Investigation of the molecular mechanisms underlying how plants sense, absorb, transport, and use K and P is an important prerequisite to improve crop nutrient utilization efficiency. In this review, we summarize current understanding of K and P transport and signaling in plants, mainly taking Arabidopsis thaliana and rice(Oryza sativa) as examples. We also discuss the mechanisms coordinating transport of N and K, as well as P and N.

关键词： phosphorus plant nutrition potassium transport signaling