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Acta Metallurgica Sinica(English Letters) 2015年第2期28卷 139-146页

作者： Qiang Guo jian-Hua Liu mei Yu Song-mei Li Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and Engineering Beihang University

The influence of rust layers on the corrosion behavior of ultra-high strength steel 300M subjected to a simulated coastal atmosphere was investigated by corrosion weight loss, surface analysis techniques, and electrochemical methods. The results exhibit the presence of a large proportion of γ-FeOOH and α-FeOOH and a small amount of Fe3O4 in the outer rust layer. During the wet-dry cyclic process, the bonding performance and the density of outer rust layer deteriorate with the thickness of outer rust. The inner rust layer plays a main role on protectiveness, which can be attributed to the formation of an ultra-dense and adherent rust film with major constituent of α-FeOOH and α-Fe2O3 on the steel.

关键词： Ultra-high strength steel Wet-dry Chloride Corrosion Rust

The Game of Cops and Robbers on Directed Graphs with Forbidden Subgraphs

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 684-689页

作者： Ming-rui LIU mei lu Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

The traditional game of cops and robbers is played on undirected graph. Recently, the same game played on directed graph is getting attention by more and more people. We knew that if we forbid some subgraph we can bound the cop number of the corresponding class of graphs. In this paper, we analyze the game of cops and robbers on H^(-)-free digraphs. However, it is not the same as the case of undirected graph. So we give a new concept(H^(-)^(*)-free digraph) to get a similar conclusion about the case of undirected graph.

关键词： cops and robbers directed graph induced subgraphs

Generation of medical isotopes ^(47)Sc,^(67)Cu through laser-induced(γ,p)reaction

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Nuclear Science and Techniques 2024年第11期35卷 219-227页

作者： jian-Yao Zhang Di Wu Hao-Yang Lan Huan-Gang lu Jia-Xin Liu jian-Feng Lv mei-Zhi Wang Xue-Qing Yan State Key Laboratory of Nuclear Physics and Technology School of PhysicsCAPTPeking UniversityBeijing 100871China Beijing Laser Acceleration Innovation Center Beijing 101407China

Short-lived medical isotopes and their generators are typically produced in nuclear reactors and cyclotrons that require extensive ***,considering the environmental concerns and economic costs of these traditional approaches,modern laser technology,which provides extremely strong electric fields within tabletop-sized areas,can serve as a potential supplementary *** specifically on the(γ,p)generation of the vital medical isotopes^(47)Sc and^(67)Cu,we used both experimental results and PIC-GEANT4 simulations to demonstrate that laser-induced photonuclear reaction is a promising method for isotope *** developed a model capable of calculating isotope yields under various laser conditions and acceleration *** findings revealed that a 200 TW laser can sufficiently produce diagnostic amounts of^(47)Sc and^(67)Cu,while simultaneously providing high specific activity,which is significant in medical applications for improving treatment efficacy,enhancing image resolution,and reducing side effects.

关键词： Photonuclear reaction Laser-drivenγ-Ray Medical isotope

Receding horizon H_∞ control for constrained time-delay systems

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Journal of Systems Engineering and Electronics 2009年第2期20卷 363-370页

作者： lu mei Jin Chengbo Shao Huihe Inst. of Automation Shanghai Jiaotong Univ. Shanghai 200240 P. R. China Dept. of Fieldbus Shanghai Automation Instrument Co. Ltd. Shanghai 200233 P. R. China Dept. of Product Design Shanghai Gaoke Valve Manufactory Co. Ltd. Shanghai 200092 P. R. China

A receding horizon Hoo control algorithm is presented for linear discrete time-delay system in the presence of constrained input and disturbances. Disturbance attenuation level is optimized at each time instant, and the receding optimization problem includes several linear matrix inequality constraints. When the convex hull is applied to denote the saturating input, the algorithm has better performance. The numerical example can verify this result.

关键词： receding horizon control Hoo control time-delay constrained input

Genetic basis and biotechnological manipulation of sexual dimorphism and sex determination in fish

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Science China(Life Sciences) 2015年第2期58卷 124-136页

作者： mei Jie GUI jian-Fang College of Fisheries Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture Freshwater Aquaculture Collaborative Innovation Center of Hubei Province Huazhong Agricultural University State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of the Chinese Academy of Sciences

Aquaculture has made an enormous contribution to the world food production,especially to the sustainable supply of animal *** utility of diverse reproduction strategies in fish,such as the exploiting use of unisexual gynogenesis,has created a typical case of fish genetic breeding.A number of fish species show substantial sexual dimorphism that is closely linked to multiple economic traits including growth rate and body size,and the efficient development of sex-linked genetic markers and sex control biotechnologies has provided significant approaches to increase the production and value for commercial *** with the rapid development of genomics and molecular genetic techniques,the genetic basis of sexual dimorphism has been gradually deciphered,and great progress has been made in the mechanisms of fish sex determination and identification of sex-determining *** review summarizes the progress to provide some directive and objective thinking for further research in this field.

关键词： reproduction strategies sexual dimorphism sex determination sex-determining gene sex chromosome sex controlbreeding

NECESSARY AND SUFFICIENT CONDITION FOR GLOBAL CONTROLLABILITY OF A CLASS OF AFFINE NONLINEAR SYSTEMS

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Journal of Systems Science & Complexity 2007年第4期20卷 492-500页

作者： Yimin SUN Shengwei mei Qiang lu Department of Electrical Engineering Tsinghua University Beijing 100084 China

In this paper, we investigate the global controllability of a class of n-dimensional affine nonlinear systems with n- 1 controls and constant control matrix. A necessary and sufficient condition for its global controllability has been obtained by using the methods recently developed. Furthermore, we generalize the above result to a class of affine nonlinear systems with a block-triangular-like structure. Finally, we will give three examples to show the applications of our results.

关键词： Affine nonlinear systems block-triangular-like structure global controllability vector field

Improved performances of lithium disilicate glass-ceramics by seed induced crystallization

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Journal of Advanced Ceramics 2021年第3期10卷 614-626页

作者： Ting ZHAO mei-mei LIAN Yi QIN jian-Feng ZHU Xin-Gang KONG jian-Feng YANG School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

Self-reinforced lithium disilicate(Li_(2)Si_(2)O_(5),LD)glass-ceramics were hot pressing sintered by introducing 5 wt%Li_(2)Si_(2)O_(5)crystal seeds into two different glass compositions of SiO_(2)-Li_(2)O-P2O_(5)-ZrO_(2)-Al_(2)O_(3)-K_(2)O-La_(2)O_(3)(7C LD)and SiO_(2)-Li_(2)O-K_(2)O-La_(2)O_(3)(4C LD).The results show that the seeds play an important role in the crystallization inducement,and microstructural and property improvement of the glass,especially for the glass powder without the nucleating agent of P_(2)O_(5).The microstructure features a wider bimodal grain size distribution with large rod-like crystals epitaxially grown along the seeds and small crystals nucleated from the glass powder itself,contributing to the improvement of the performance especially the fracture *** specimen of 4C LD glass with the addition of 5 wt%Li_(2)Si_(2)O_(5) seeds exhibited the best comprehensive properties with a good flexural strength(396±7 MPa),improved fracture toughness(3.31±0.19 MPa·m^(1/2)),and comparable translucency as IPS *** research provides a new idea and method for the improvement of the fracture toughness of lithium disilicate glass-ceramics without affecting its aesthetic appearance,and lays the foundation for its clinical applications.

关键词： lithium disilicate(LD) seeds mechanical properties translucency

Exploiting quasi-one-dimensional confinement for proficient hydrogen production from formic acid at room temperature

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Journal of Energy Chemistry 2020年第10期29卷 205-213页

作者： Tao jiang Peng lu Meng-Jiao Xu jian-Dong Lin Yong-mei Liu Yong Cao He-Yong He Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200433China

We describe herein that the quasi-one-dimensional confinement effect of functionalized nanoporous supports is particularly advantageous for boosting formic acid(FA)dehydrogenation efficiency over palladium nanoparticles(NPs).Benefiting from their unique structural merits that lead to significant lowering of the entropic barrier for FA activation,the Pd NPs interiorly located on the amino-modified MCM-41 offer the promise of more than an order of magnitude speedup of the initial activity in H2 production from FA over their exterior *** mild and additive-free conditions,ultrafine Pd NPs confined in aminomodified MCM-41 channels exhibit an initial turnover frequency as high as 46,677 h-1 and a turnover number up to 1,060,000 at 60℃.In conjunction with the enhancement and robust performance for efficient regeneration of FA via CO2 hydrogenation,the presented approach greatly contributes to the development of FA-based hydrogen storage and related technologies as viable means of enabling sustainable future energy prospects.

关键词： Confinement effect Formic acid Heterogeneous catalysis Hydrogen storage

Flight behavior of the sycamore lace bug, Corythucha ciliata, in relation to temperature, age, and sex

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Journal of Integrative Agriculture 2019年第10期18卷 2330-2337页

作者： lu Shao-hui WEI mei-cai YUAN Guo-jun CUI jian-xin GONG Dong-feng Laboratory of Insect Systematics and Evolutionary Biology Central South University of Forestry and TechnologyChangsha 410000P.R.China Henan Academy of Forestry Zhengzhou 450000P.R.China Henan Institute of Science and Technology Xinxiang 453000P.R.China

The flight capacity of different ages and sexes of the sycamore lace bug, Corythucha ciliata, was studied at different temperatures using a flight mill system. The results of regression analysis showed a significant effect of temperature on flight distance (P=0.0082). Temperature did not influence flight duration (P=0.212) or flight speed (P=0.175). The mean flight distance (1 024 m) and mean flight duration were the greatest at 25.2°C. The age of C. ciliata had a significant influence on flight distance (P=0.0005), flight duration (P=0.0005) and flight speed (P=0.026). The 12-d-old adult had the greatest flight distance (887 m), duration (3 875 s) and speed (0.22 m s^–1). Flight distances and flight duration of females were significantly longer than that of males. However, the male had significantly greater flight speed than the female. The insect appears to be capable of long distance flights. The understanding of the optimal age and temperature for the flight of this insect through this study provides a foundation for better management of the insect in China.

关键词： Corythucha ciliata flight capacity tethered flight temperature age and sex

Rational construction of a cellular memory inverter

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Science China(Information Sciences) 2015年第1期58卷 99-106页

作者： CHEN mei ZHANG lu XU Jin School of Information Engineering Minzu University of China Institute of Software School of Electronics Engineering and Computer ScienceKey Laboratory for High Confidence Software Technologies of Ministry of EducationPeking University

Robust and reliable biological memory computing systems are lacking, although many biological computing systems are implemented. We successfully designed, constructed, and tested a cellular memory inverter in the bacterium Escherichia coli in a predictable way. We selected isopropyl-D-1-thiogalactopyranoside(IPTG) as the input and green fluorescent protein(GFP) as the output. We selected negative regulation of lac operon and excision function of Cre recombinase as computing tools. The GFP can express and produce output without IPTG. The input, IPTG, can induce the expression of Cre recombinase. The Cre recombinase can excise the GFP gene between site lox71 and site lox66, and hence turn off the output. We also selected ordinary differential equations(ODEs) to predict the dynamic behaviors for the precise design and implementation of the inverter. We used sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE), colony Polymerase Chain Reaction(PCR), and fluorescent quantitative analysis techniques to verify the function of our *** study provides a new biological memory computing system. The Cre recombinase functions used here should be useful in the construction of biological memory computing systems.

关键词： cellular memory inverter lac operon cre recombinase ordinary differential equation(ODE) biological computing system