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Journal of Integrative Plant Biology 2006年第12期48卷 1415-1423页

作者： Ren-Jun Wang hui Xiao Pei-Yu Zhang liang qu Heng-Jiang Cai Xue-Xi Tang Marine Ecology Laboratory Ocean University of China Qingdao 266003 China Department of Environmental Science and Engineering Qingdao University Qingdao 266071 China

In the present study, we evaluated the allelopathic effects of three macroalgae, namely Ulva pertusa Kjellml, Corallina pilufifera Postl et Ruprl, and Sargassum thunbergii Mertl O. Kuntze, on the growth of the microalga Skeletonema costaturn （Grev.） Creve using culture systems in which the algae coexisted. The effects of the macroalgal culture medium filtrate on S. costatum were also investigated. Moreover, isolated co-culture systems were built to confirm the existence of allelochemicals and preclude growth inhibition by direct contact. The coexistence assay data demonstrated that the growth of S. costaturn was strongly inhibited when fresh tissues, dry powder and aqueous extracts were used; the allelochemicals were lethal to S. costatum at relatively higher concentrations. The effects of the macroalgal culture medium filtrate on the microalga showed both species specificity and complexity. The inhibitory effect of fresh macroalgal tissue and culture medium filtrate on the microalga was due to the alleochemicals released by the macroalgae. The results of the present study show that the allelopathic effects of macroalgae on the microalga are complex. The present study could shed light onto the basis of the interaction between macro- and microalgae.

关键词： allelopathic effects Corallina pilulifera Skeletonema costatum Sargassum thunbergii Ulva pertusa.

Effects of heat treatment on the corrosion resistance of carbon steel coated with LaMgAl_(11)O_(19) thermal barrier coatings

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1050-1059页

作者： liang-liang Huang hui-min Meng Li-kang liang Sen Li Jin-hui Shi Institute for Advanced Materials and Technology University of Science and Technology Beijing

LaMgAl11O19thermal barrier coatings（TBCs） were applied to carbon steels with a NiCoCrAlY bond coat by plasma spraying. The effects of heat treatment on the corrosion resistance of carbon steel coated with LaMgAl11O19TBCs were investigated in 3.5wt% Na Cl solution using polarization curves, electrochemical impedance spectroscopy（EIS）, scanning electron microscopy（SEM）, and X-ray diffraction（XRD）. The results show that a large number of cracks are found in the LaMgAl11O19TBCs after the samples are heat-treated, including some through-thickness cracks. The corrosion forms of the as-sprayed and heat-treated TBCs are uniform corrosion and pitting corrosion, respectively. The as-sprayed TBCs exhibit three EIS time constants after being immersed for less than 7 d, and then a new time constant appears because of steel substrate corrosion. When the immersion time is increased to 56 d, a Warburg impedance（W） component appears in the EIS data. The EIS data for the heat-treated TBCs exhibit only two time constants after the samples are immersed for less than 14 d, and a new time constant appears when the immersion time is increased further. The heat treatment reduces the corrosion resistance of carbon steel coated with LaMgAl11O19TBCs. The corrosion products are primarily γ-Fe OOH and Fe3O4.

关键词： thermal barrier coatings carbon steel corrosion pl

Rapid heating thermal shock study of ultra high temperature ceramics using an in situ testing method

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Journal of Advanced Ceramics 2017年第4期6卷 279-287页

作者： Rujie HE Zhaoliang qu Dong liang Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081China

In this paper,the rapid cooling thermal shock behaviors of ZrB_(2)-SiC ceramics were measured using traditional water quenching method,and the rapid heating thermal shock behaviors of ZrB_(2)-SiC ceramics were investigated using a novel in situ testing *** measured critical thermal shock temperature difference for rapid cooling thermal shock was 373.6℃;however,the critical thermal shock temperature difference for rapid heating thermal shock of ZrB_(2)-SiC ceramics was measured to be as high as 1497.2℃.The thermal stress distribution states after rapid cooling thermal shock and rapid heating thermal shock testing were analyzed using finite element analysis(FEA)*** FEA results showed that there is a tensile stress existed on the surface for rapid cooling thermal shock,whereas there is a compressive stress existed on the surface for rapid heating thermal *** difference of thermal stress distribution resulted in the difference of the critical temperature difference for rapid cooling thermal shock and rapid heating thermal shock.

关键词： ultra high temperature ceramics(UHTCs) thermal shock behavior thermal stress finite element analysis(FEA)

Mitochondrial sirtuins,metabolism,and aging

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Journal of Genetics and Genomics 2022年第4期49卷 287-298页

作者： Zhejun Ji Guang-hui Liu Jing qu State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Advanced Innovation Center for Human Brain Protection National Clinical Research Center for Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China

Maintaining metabolic homeostasis is essential for cellular and organismal health throughout *** signaling pathways that regulate metabolism also play critical roles in aging,such as PI3K/AKT,mTOR,AMPK,and sirtuins(SIRTs).Among them,sirtuins are known as a protein family with versatile functions,such as metabolic control,epigenetic modification and lifespan ***,by understanding how sirtuins regulate metabolic processes,we can start to understand how they slow down or accelerate biological aging from the perspectives of metabolic ***,we review the biology of SIRT3,SIRT4,and SIRT5,known as the mitochondrial sirtuins due to their localization in the mitochondrial ***,we will discuss canonical pathways that regulate metabolism more broadly and how these are integrated with aging ***,we will summarize the current knowledge about functional differences between SIRT3,SIRT4,and SIRT5 in metabolic control and integration in signaling ***,we will discuss how mitochondrial sirtuins regulate processes associated with aging and aging-related diseases.

关键词： Metabolism and aging regulation Mitochondrial sirtuins Aging-related diseases SIRT3 SIRT4 SIRT5

Nonlinear instability suppression of closed-loop pilot-vehicle system with rate-limiting actuator based on anti-windup compensation

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Journal of Systems Engineering and Electronics 2016年第4期27卷 892-899页

作者： liang qu Yinghui Li Haojun Xu Qimeng Cao Aeronautics and Astronautics Engineering College Air Force Engineering University

To solve the flight safety problem caused by nonlinear instabilities（category II pilot induced oscillations, PIOs） of the closed-loop pilot-vehicle system with rate-limiting actuator, the antiwindup（AW） compensation method to avoid category II PIOs is investigated. Firstly, the AW compensation method originally used for controlling input magnitude limited system is introduced, then this method is extended for controlling input rate-limiting system through a circle criterion theorem. Secondly, the establishment of the AW compensator is transformed into the solving of linear matrix inequalities. Finally, an AW compensator establishment algorithm for the closed-loop pilot-vehicle system with the rate-limiting actuator is obtained. The effectiveness of the AW compensation method to avoid category II PIOs is validated by time-domain simulations,and compared with rate-limited feedback（RLF） command rate compensation method. The results show that the AW compensation method can effectively suppress category II PIOs and maintain the nominal performance when the closed-loop pilot-vehicle system is normal. Unlike the command rate compensator which works upon system uninterruptedly, the AW compensation method affects the closed-loop pilot-vehicle system only when the rate-limiting of actuator is activated, so it is a novel PIO avoidance method.

关键词： rate-limiting pilot induced oscillation(PIO) antiwindup(AW) compensation closed-loop pilot-vehicle system linear matrix inequality command rate compensation

Neutron matter properties from relativistic Brueckner-Hartree-Fock theory in the full Dirac space

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Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 67-74页

作者： Xiaoying qu hui Tong Chencan Wang Sibo Wang School of Mechatronics Engineering Guizhou Minzu UniversityGuiyang 550025China College of Physics and Materials Science Tianjin Normal UniversityTianjin 300387China Strangeness Nuclear Physics Laboratory RIKEN Nishina CenterWako 351-0198Japan School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Department of Physics Chongqing UniversityChongqing 401331China

A novel description of the strongly interacting pure neutron matter(PNM)was carried out by the relativistic Brueckner-HartreeFock(RBHF)theory in the full Dirac space with Bonn A *** scalar and vector components of the single-particle potentials are shown as functions of the momentum and the density,and are compared with the results obtained by the RBHF calculations in the Dirac space without negative-energy *** benchmarking the binding energies of PNM to those predicted by several ab initio methods in the nonrelativistic framework with two-and three-body forces,we find our results are softer than those from the Brueckner-Hartree-Fock theory with the inclusion of three-body force,and in harmony with the ones obtained by the Monte Carlo method and many-body perturbation theory within *** addition,the equation of state for neutron star matter is consistent with the constraints from multi-messenger astrophysical observation and heavy-ion collision *** tidal deformabilities of a binary neutron star system are calculated and found consistent with the constraints from GW170817.

关键词： neutron matter properties relativistic Brueckner-Hartree-Fock full Dirac space

Preparation and Electrochemical Properties of the Pd-modified Cu Electrode for Nitrate Reduction in Water

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Chinese Chemical Letters 2006年第1期17卷 61-64页

作者： Ying WANG Jiu hui qu hui Juan LIU State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Beijing 100085 Graduate School of the Chinese Academy of Sciences Beijing 100039

The Pd-modified Cu （Pd/Cu） electrodes for nitrate reduction were prepared using electro-deposition method at different potentials, Compared with other different electrodes so far studied in our work （Cu, Sn/Cu and Pd/Ti electrode） using cyclic voltammetry method, Pd/Cu electrode showed the highest electrocatalytic capacity of nitrate reduction. It was found that at more negative electrode potential the smaller Pd particles formed on the Cu electrode, which was beneficial to the nitrate reduction. With increasing deposition amount of Pd, the capacity of nitrate reduction increased. Too rich Pd, however, has a negative influence on the capacity of nitrate reduction. In our study, the maximum nitrate reduction current was 2.07 mA/cm^2, when electrodeposition potential of Pd was -0.3 V and deposition amount was 0.9 C.

关键词： Nitrate reduction electro-deposition potentials water treatment.

Fabrication and thermal stability of Ni-P coated diamond powder using electroless plating

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 479-486页

作者： Ying-hu Dong Xin-bo He Ud-din Cai-yu Guo liang Xu Yu-ting Huang Xuan-hui qu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering Nanchang Hangkong University Nanchang 330063 China Fuel Cell Division Pakistan Institute of Nuclear Science and Technology Islamabad 44000 Pakistan

Ni-P coated diamond powder was fabricated successfully by using electroless *** of active solutions,plating time,reaction temperature,and the components of the plating bath on the Ni-P coating were investigated ***,a study on the thermal stability of Ni-P coated diamond under various atmospheres was *** results indicate that Pd atoms absorbed on the diamond surface as active sites can consequently enhance the deposition rate of Ni *** optimized plating bath and reaction conditions improve both the plating speed and the coverage rate of Ni-P electroless plating on the diamond *** to the diamond substrate,the diamond coated with Ni-P films exhibits very high thermal stability and can be processed up to 900°C in air and 1300°C in protective atmosphere such as H2.

关键词： synthetic diamonds electroless plating thermal stability particulates

Sensor fault-tolerant observer applied in UAV anti-skid braking control under control input constraint

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Journal of Systems Engineering and Electronics 2017年第1期28卷 126-136页

作者： hui Sun Jianguo Yan Yaohong qu Jie Ren School of Automation Northwestern Polytechnical University Chengdu Aircraft Industrial (Group) Co. Ltd.

This paper proposes a method for addressing the problem of sensor fault-tolerant control (FTC) for anti-skid braking systems (ABSs). When the wheel velocity sensor of the ABS for unmanned aerial vehicles (UAVs) becomes faulty, wheel velocity failure and feedback instability may occur. Firstly, a fault diagnosis and isolation (FDI) method based on a sliding mode observer approach is introduced to detect and isolate the fault of the sensor. When the wheel velocity sensor is in healthy conditions, the observer works in a diagnosis mode. If faults occur in the sensor, it acts as a wheel velocity estimator. Secondly, an FTC strategy, adopting a feedback compensation structure, is designed with input control constraints. In addition, based on the FDI result, a terminal sliding mode (TSM) controller is designed to guarantee that slip-ratio tracks its appropriate reference values in situations where runways change conditions during landing. The control system switches automatically from control using a wheel velocity sensor to sensorless control mode, so the observer-based FTC scheme is established. It is logical that the ABS keeps observed-state and remains stable when the wheel velocity sensor is broken and during external disturbance. Finally, simulation results show the effectiveness of the proposed method. © 1990-2011 Beijing Institute of Aerospace Information.

关键词： Braking Control systems Failure analysis Fault tolerance Feedback Sensorless control Sliding mode control Unmanned aerial vehicles (UAV) Velocity Wheels

X-ray tomography analysis of aluminum alloy powder compaction

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Rare Metals 2022年第9期41卷 3244-3250页

作者： Shi-Di Yang Rui-Jie Zhang Xuan-hui qu State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing100083China School of Material Science and Engineering University of Science and Technology BeijingBeijing100083China

Aluminum alloy green compacts obtained by single-action compaction in lubricated and unlubricated dies were investigated by X-ray *** the purpose of obtaining the relationship between the density of green compact and the gray value of reconstructed images,linear fitting was *** results show that these data have excellent linear ***,a new method for analysis of compaction process was presented in this *** quantitative analysis of the density and compressive pressure distribution in green compacts was *** compressive pressure transmitted ratio and friction index were also *** is found that the lubricated die wall has better effects on the density homogeneity at lower applied compressive *** compaction process,the densification of powder particles in the die mainly occurs in the lower part of the green compact and the factor which mainly influences the friction between die wall and green compact is the applied compressive pressure.

关键词： Green compact Density distribution Compaction Compressive pressure distribution