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A new bionic MAV's flapping motion based on fruit fly hovering at low Reynolds number

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Acta Mechanica Sinica 2007年第5期23卷 485-493页

作者： Peng Bai Erjie cui feng Li Weijiang Zhou Bingyan Chen China Academy of Aerospace Aerodynamics Beijing 100074 China

On the basis of the studies on the high unsteady aerodynamic mechanisms of the fruit fly hovering the aerodynamic advantages and disadvantages of the fruit fly flapping motion were analyzed. A new bionic flapping motion was proposed to weaken the disadvantages and maintain the advantages, it may be used in the designing and manufacturing of the micro air vehicles （MAV＇s）. The translation of the new bionic flapping motion is the same as that of fruit fly flapping motion. However, the rotation of the new bionic flapping motion is different. It is not a pitching-up rotation as the fruit fly flapping motion, but a pitching-down rota- tion at the beginning and the end of a stroke. The numerical method of 3rd-order Roe scheme developed by Rogers was used to study these questions. The correctness of the numerical method and the computational program was justified by comparing the present CFD results of the fruit fly flapping motion in three modes, i.e., the advanced mode, the symmetrical mode and the delayed mode, with Dickinson＇s experimental results. They agreed with each other very well. Subsequently, the aerodynamic characteristics of the new bionic flapping motion in three modes were also numerically simulated, and were compared with those of the fruit fly flap- ping. The conclusions could be drawn that the high unsteady lift mechanism of the fruit fly hovering is also effectively utilized by this new bionic flapping. Compared with the fruit fly flapping, the unsteady drag of the new flapping decreases very much and the ratio of lift to drag increases greatly. And the great discrepancies among the mean lifts of three flapping modes of the fruit fly hovering are effectively smoothed in the new flapping. On the other hand, this new bionic flapping motion should be realized more easily. Finally, it must be pointed out that the above conclusions were just drawn for the hovering flapping motion. And the aerodynamic characteristics of the new bionic flapping motion in forwa

关键词： Flapping wing Low Reynolds number.MAV's Unsteady Numerical simulation

Orientation gradient on surface of non-oriented electrical steel annealed by γ → α transformation

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Journal of Iron and Steel Research International 2020年第1期27卷 88-95页

作者： Jin-hua Wang Ping Yang Wei-min Mao feng-e cui School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The microstructures and textures of the non-oriented electrical steel sheets under various annealing conditions were *** orientation gradient in the interior of grains appeared on the surface of steel sheets after α→γ→α transformation in various *** orientation gradient that appeared on the surface was inherited into the center of the steel sheet in H2 atmosphere,while that appeared only in the grains of the surface layer during γ→α transformation with N2 *** thin oxide scale was generated in various atmospheres containing traces of O2 and *** formation mechanism of orientation gradient is related to the thermal stress caused by the difference of thermal expansion coefficients between the oxide scale and the thin ferrite on the *** combined effect of phase transformation stress and thermal stress caused the plastic deformation of the thin ferrite grains on the surface in the initial stage of γ→α transformation,and then the orientations of the thin ferrite grains gradually rotated and caused the orientation gradient in the interior of grains.

关键词： Electrical steel Texture Phase transformation-Thermal stress Oxide scale

Temperature and electron density of soil plasma generated by LA-FPDPS

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Frontiers of physics 2012年第6期7卷 721-727页

作者： Xia-Fen Li Wei-Dong Zhou Zhi-feng cui The Institute of Information Optics Zhejiang Normal UniversityJinhua 321004China Department of Physics Anhui Normal UniversityWuhu 241000China

Electron temperature and electron number density are important parameters in the characterization of plasma. In this paper the electron temperature and electron number density of soil plasma generated by laser ablation combined with nanosecond discharge spark at different discharge voltages have been studied. Saha-Boltzmann plot and Stark broadening are used to determine the temper- ature and electron number density. It is proved that local thermal equilibrium is fulfilled in the nanosecond spark enhanced plasma. The enhanced optical emission, signal to noise ratio and the stability in term of the relative standard deviation of signal intensity at different spark voltages were investigated in detail. A relative stable discharge process was observed with use of a 10 kV discharge voltage under the carried experimental configuration.

关键词： laser ablation fast pulse discharge plasma spectroscopy (LA-FPDPS) local thermodynamic equilibrium (LTE) electron temperature electron number density discharge voltage

Progress and Prospects of China in Implementing the Goal 14 of the 2030 Agenda for Sustainable Development

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Chinese Journal of Urban and Environmental Studies 2019年第1期7卷 105-117页

作者： cui feng SHEN Bin College of Marine Culture and Law Shanghai Ocean University School of Law Ocean University of China

Following the entry into force of the 2030 Agenda for Sustainable Development, China has rapidly established key areas and priorities for its implementation, and Goal 14 focusing on sustainable marine development(hereinafter referred to as “SDG 14”) has been attached with great importance. This paper illustrates China’s implementation of SDG14 from four aspects:marine pollution control, conservation of marine environment, sustainable utilization of marine resources and international cooperation in global governance, and concludes that SDG14 has been implemented well on the whole in China. On this basis, the paper looks to the future sustainable development of ocean in China, and suggests improving the legal system, strengthening marine environmental monitoring, and advancing international cooperation for ocean sustainable development.

关键词： The 2030 Agenda for Sustainable Development SDG14 marine resources marine environment

Conformational and Dynamical Evolution of Block Copolymers in Shear Flow

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Chinese Journal of Polymer Science 2021年第5期39卷 640-650,I0009页

作者： Xiang-Xin Kong Wen-Duo Chen feng-Chao cui Yun-Qi Li Key Laboratory of High-Performance Synthetic Rubber and Its Composite Materials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China School of Information Engineering Jilin Engineering Normal UniversityChangchun 130052China School of Materials Sun Yat-sen UniversityGuangzhou 510275China Key Laboratory of Polyoxometalate Science of the Ministry of Education and Faculty of Chemistry Northeast Normal UniversityChangchun 130024China

Conformation and dynamical evolution of block copolymers in shear flow is an important topic in polymer physics that underscores the forming process of various *** explored deformation and dynamics of copolymers composed of rigid or flexible blocks in simple shear flow by employing multiparticle collision dynamics integrated with molecular dynamics *** found that compared with the proportion between rigid and flexible blocks,the type of the central blocks plays more important role in the conformational and dynamical evolution of *** is,if the central block is a coil,the copolymer chain takes end-over-end tumbling motion,while if the central block is a rod,the copolymer chain undergoes U-shape or S-shape deformation at mid shear *** the shear strength increases,all copolymers behave similar to flexible polymers at high shear *** can be attributed to the fact that shear flow is strong enough to overcome the buckling force of the rigid *** results provide a deeper understanding of the roles played by rod and coil blocks in copolymers for phase interface during forming processing.

关键词： Block copolymer Shear flow Multiparticle collision dynamics Molecular dynamics simulations Conformation

SPT6L Encoding a Putative WG/GW-Repeat Protein Regulates Apical-Basal Polarity of Embryo in Arabidopsis

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Molecular Plant 2012年第1期5卷 249-259页

作者： Xiao-Lu Gu Hua Wang Hai Huang Xiao-feng cui National Laboratory of Plant Molecular Genetics Shanghai Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChineseAcademy of Sciences300 Fenglin RoadShanghai 200032China

In eukaryotes, a protein motif consisting of WG/GW repeats, also called the Argonaute （AGO） hook, is thought to be essential for binding AGO proteins to fulfill their functions in RNA-mediated gene silencing. Although a number of WG/GW-containing proteins have been computationally identified in Arabidopsis, their roles in plant growth and development are unknown. Here, we show that the Arabidopsis Suppressor of Ty insertion 6-like （SPT6L） gene, which encodes a protein with C-terminal WG/GW repeats, plays critical roles in embryonic development. SPT6L is evolutionarily conserved only in vascular plants, with varying numbers of C-terminal WG/GW repeats, which are plant-species specific. spt61 mutants formed embryos with an aberrant apical-basal axis, showing insufficient development of the basal domain and embryonic lethality. Expression domains of the class-Ill homeodomain-leucine zipper （HD-ZIP III） genes PHABULOSA （PHB） and PHAVOLUTA （PHV） were expanded in the spt61 embryo. In contrast, the PLETHORA1 （PLT1） gene, which acts antagonistically to the HD-ZIP III genes in specification of basal fate, was severely down-regulated in the spt61 mutant. Furthermore, the phb phv double mutations partially rescued aberrant basal development in the spt61 background and restored PLT1 expression. Collectively, our results indicate that SPT6L is essential for specification of the apical-basal axis, partly by controlling the HD-ZIP III genes in embryos.

关键词： Arabidopsis embryo HD-ZIP ill polarity SPT6L.

Polymorphisms in salivary-gland transcripts of Russian wheat aphid biotypes 1 and 2

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Insect Science 2012年第4期19卷 429-440页

作者： feng cui Michael Smith John Reese Owain Edwards Gerald Reeck Department of Biochemistry Kansas State UniversityManhattanKansasUSA State Key Laboratory of Integrated Managementof Pest Insects&Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina Department of Entomology Kansas StateUniversityManhattanKansasUSA CSIRO Entomology Canberra CooperaEve Research Centre for Plant Biosecufity CanberraAustralia

The Russian wheat aphid （RWA）, Diuraphis noxia （Mordvilko）（Homoptera： Aphididae）, is a major pest of small grains. As with plant-feeding aphids in general, the interaction between RWA and host plants is governed, on the insect side, by proteins and enzymes in saliva. In this work, we examined sequence variations in transcripts encoding proteins and enzymes of RWA salivary glands. We conducted reverse transcription - polymerase chain reaction in RWA biotypes 1 and 2 using primers derived from pea aphid orthologs, and cloned regions of 17 putative salivary gland transcripts. For four of the transcripts, we observed no difference in sequences between the two biotypes. For the other 13 transcripts, for example, the transcripts encoding sucrase, trehalase and protein C002, large amount of variations, both within each biotype and between the two biotypes, were observed. Usually the two biotypes shared only one variant, which was typically the most common variant in both biotypes. Most of the transcripts had more non-synonymous than synonymous codon changes among their variants. Our results offer possible molecular markers for distinguishing the two biotypes and insights into their evolution.

关键词： biotype molecular marker polymorphism Russian wheat aphid salivarygland transcript

Promotion of hexadecyltrimethyleamine bromide to the damage of Alexandrium ***3 by cupric glutamate

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Journal of Environmental Sciences 2006年第6期18卷 1152-1156页

作者： LI Hao MIAO Jin-lai cui feng-xia LI Guang-you Key Laboratory of Marine Biological Active Substances SOA Qingdao 266061 China Institute of Radiation Medicine Academy of Military Medical Sciences Beijing 100850 China College of Food Science and Technology Ocean University of China Qingdao 266003 China

The effect of hexadecyltrimethyleamine bromide （HDTMAB） on the removal of A lexandrium sp. LC3 under cupric glutamate stress was investigated. Toxic effect of cupric glutamate on A lexandrium sp. LC3 was significantly promoted in the presence of HDTMAB, especially at 3.0 cmc of HDTMAB. It was found that the sulfhydryl group content of the cell decreased, while the malonaldehyde content and membrane permeability increased when A lexandrium sp. LC3 was treated with HDTMAB and cupric glutamate complex, compared with cupric glutamate alone. The data suggest that HDTMAB might stimulate the damage of A lexandrium sp. LC3 by enhancing the membrane permeability.

关键词： HDTMAB cupric glutamate A lexandrium sp. LC3 cell membrane permeability

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Keep-up English(18)

解放军外国语学院学报 1992年第6期15卷 53-56页

作者： feng cui Hua

black spot n. center of poverty, danger, disturbance; a difficult place, or situation贫困、危险,问题较多的地方-unemployment black spots (American Speech, Fall 1987) bread and butter a. long-standing, reliable (source of business, profit, etc.)可靠的,能保证长期收入的- Yet the Bank of England ... is happy to let them rebuild their balance sheets at the expense of their bread and butter customers (The Sunday Times, 26.5.91)- ... bread and butter TV programs (= long-running programs, e.g. soap operas, serials, etc.)

关键词：长期收入贫困危险可靠地方敏感问题环境无害航空路线保证

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