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抗药性朱砂叶螨实验种群生命表参数研究

西南农业学报 2003年第2期16卷 63-65页

作者：邓新平何林刘怀彭梅西南农业大学农业部重庆市昆虫学及害虫控制工程重点实验室重庆400716

系统观察了朱砂叶螨抗甲氰菊酯品系和敏感品系实验种群在26℃下的生长发育和生殖情况,并通过组建2品系的生命生殖力表,用种群生命表参数分析抗性种群与敏感种的生态适合度差异。实验结果表明抗甲氰菊酯品系(Rf)的发育历期和寿命缩短,产... 详细信息

系统观察了朱砂叶螨抗甲氰菊酯品系和敏感品系实验种群在26℃下的生长发育和生殖情况,并通过组建2品系的生命生殖力表,用种群生命表参数分析抗性种群与敏感种的生态适合度差异。实验结果表明抗甲氰菊酯品系(Rf)的发育历期和寿命缩短,产卵量下降。敏感品系平均寿命为35 31d,平均每雌产卵量为185 00粒;抗性品系分别为29 58d,134 67粒。抗甲氰菊酯品系的净生殖率(R0=139 2147)显著低于敏感品系(R0=180 6388)。抗甲氰菊酯品系内禀增长率(rm)、周限增长率(λ)和种群加倍时间(p.b.t)分别为0 2272、1 2551和3 0508,并与敏感品系的内禀增长率、周限增长率和种群加倍时间差异不显著。

关键词：抗药性朱砂叶螨实验种群种群生命表参数甲氰菊酯杀虫剂综合治理农业害螨

Optimal design of pressure vessel using an improved genetic algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1264-1269页

作者： Peng-fei liu ping XU Shu-xin HAN Jin-yang ZHENG Institute of Chemical Machinery and Process Equipment Zhejiang University Hangzhou 310027 China Institute of Applied Mechanics Zhejiang University Hangzhou 310027 China Hangzhou Special Equipment Inspection Institute Hangzhou 310003 China

As the idea of simulated annealing (SA) is introduced into the fitness function, an improved genetic algorithm (GA) is proposed to perform the optimal design of a pressure vessel which aims to attain the minimum weight under burst pressure con- straint. The actual burst pressure is calculated using the arc-length and restart analysis in finite element analysis (FEA). A penalty function in the fitness function is proposed to deal with the constrained problem. The effects of the population size and the number of generations in the GA on the weight and burst pressure of the vessel are explored. The optimization results using the proposed GA are also compared with those using the simple GA and the conventional Monte Carlo method.

关键词： Pressure vessel Optimal design Genetic algorithm (GA) Simulated annealing (SA) Finite element analysis (FEA)

Exact mesh shape design of large cable-network antenna reflectors with flexible ring truss supports

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Acta Mechanica Sinica 2014年第2期30卷 198-205页

作者： Wang liu Dong-Xu Li xin-Zhan Yu Jian-ping Jiang College of Aerospace Science and Engineering National University of Defense Technology Academy of Space Information System Academy of Space Electronic Information Technology

An exact-designed mesh shape with favorable surface accuracy is of practical significance to the performance of large cable-network antenna reflectors. In this study, a novel design approach that could guide the generation of exact spatial parabolic mesh configurations of such reflector was proposed. By incorporating the traditional force density method with the standard finite element method, this proposed approach had taken the deformation effects of flexible ring truss supports into consideration, and searched for the desired mesh shapes that can satisfy the requirement that all the free nodes are exactly located on the objective paraboloid. Compared with the conventional design method,a remarkable improvement of surface accuracy in the obtained mesh shapes had been demonstrated by numerical examples. The present work would provide a helpful technical reference for the mesh shape design of such cable-network antenna reflector in engineering practice.

关键词： Cable-network Mesh shape design Support deformation Force density Surface accuracy

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64排螺旋CT血管造影评价左心房囊样结构

实用放射学杂志 2008年第11期24卷 1483-1486页

作者：孟小茜赵亮顾玲玲蒯新平刘士远肖湘生第二军医大学上海长征医院影像科第二军医大学上海长征医院心内科

目的探讨64排螺旋CT心电门控血管造影评价左心房囊样结构的形态和分布规律。方法回顾性分析2007-08—2007-12间160例行64排MSCT心电门控心脏血管造影检查病人的左心房解剖,通过工作站后处理利用最大密度投影,多平面重建及容积重建图像... 详细信息

目的探讨64排螺旋CT心电门控血管造影评价左心房囊样结构的形态和分布规律。方法回顾性分析2007-08—2007-12间160例行64排MSCT心电门控心脏血管造影检查病人的左心房解剖,通过工作站后处理利用最大密度投影,多平面重建及容积重建图像发现突出左心房表面的囊样结构,评价其临床价值。结果160例患者中有左心房囊样结构者25例,其中男21例,女4例,年龄38～74岁,平均57岁。25(约16%)例中共发现囊样结构29个,有4例存在2个囊样结构。在分布上19个(65.51%)位于左心房右顶壁,其中6个为Ⅰ型,13个为Ⅱ型;6个(20.69%)位于左顶壁,3个为Ⅰ型,3个为Ⅱ型;4个(13.80%)位于左心房左下壁,3个为Ⅰ型,1个为Ⅱ型;未发现位于右下壁者。结论64排CT心电门控心脏血管造影能够很好地发现和评价左心房囊样结构。

关键词：心脏心房憩室体层摄影术,X线计算机

Cutting Performance and Wear Behavior of AITiN-and TiAlSiN-Coated Carbide Tools During Dry Milling of Ti-6Al-4V

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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 459-470页

作者： Jie liu Shui-Sheng Zhu xin Deng Jian-Ye liu Zhong-ping Wang Zhi Qu School of Electromechanical Engineering University of Technology Guangzhou 510006China School of Electromechanical Engineering Guangzhou Panyu PolytechnicGuangzhou 511483China Guangdong Hanbang 3d Technology Co. Ltd.Zhongshan 528427China Heyuan Fuma Cemented Carbide Co. Ltd.Heyuan 517583China Guangdong Fenghua Zhuoli Technology Co. Ltd.Foshan 528225China

Machining,especially dry machining of titanium alloys,has been one of the most significant challenges for carbide cutting *** this study,aluminum-rich AlTiN coating,as well as TiAlSiN nanocomposite coating,were successfully employed for dry milling of Ti-6 A1-4 V alloy with high efficiency and long tool *** the cutting speeds of 150 m/min and 200 m/min,the tool life of the TiAlSiN-coated tool exceeds that of AlTiN-coated tool by 32 and 66%,*** wear modes for both coated tools include the uniform flank wear,smooth wear,chipping,coating and substrate flaking,crater and notch wear,and the wear mechanisms include adhesion,diffusion,oxidation and *** them,the wear mechanism is dominated by the adhesion and oxidation *** compared with AlTiN coating,TiAlSiN coating exhibits better mechanical properties and oxidation resistance,which contribute to a better cutting performance,fewer thermal cracks and smaller and uniform workpiece chips during the dry milling of Ti-6 A1-4 V alloy.

关键词： Cutting performance Wear behavior Ti-6Al-4V AlTiN coating TiAlSiN coating

Study of thermal decoherence of harmonic oscillators

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原子与分子物理学报 2025年第5期42卷 108-114页

作者： LI Jian ZHOU Gao-Liang YAN Zheng-xin liu Wei WANG Zhao-Qi College of Science Xi’an University of Science and TechnologyXi’an 710054China

The thermal decoherence of harmonic oscillators is investigated *** quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental *** are various environmental oscillators with different angular frequency(below an ultraviolet cutoff).At the beginning,the quantum system is a pure state and the environmental oscillators are in thermodynamic equilibrium with *** a period,the system-environment interactions inspire significant decoherence of the quantum *** decoherence is displayed by explicit calculations of the purity and von Neumann entropy of the quantum *** is worth noting that the decoherence could be significant even in the weak coupling and low temperature case due to the large amount of environmental degrees of *** the decoherence process is inspired between the quantum system and an ordinary thermal environment here,the thermal decoherence result is quite general.

关键词： Quantum decoherence Grand canonical ensemble Oscillators

Repeater jamming suppression method for pulse Doppler fuze based on identity recognition and chaotic encryption

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Defence Technology（防务技术） 2021年第3期17卷 1002-1012页

作者： Jian Dai xin-hong Hao Qiang liu Xiao-peng Yan ping Li Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China Ordnance Science Institute of China Beijing 100089China

Pulse Doppler(PD) fuze is widely used in current battlefield. However, with the threat of repeater jamming, especially digital radio frequency memory technology, the deficiency in the anti-repeater jamming of a traditional PD fuze increasingly emerges. Therefore, a repeater jamming suppression method for a PD fuze based on identity(ID) recognition and chaotic encryption is proposed. Every fuze has its own ID which is encrypted with different chaotic binary sequences in every pulse period of the transmitted signal. The thumbtack-shaped ambiguity function shows a good resolution and distance cutoff characteristic. The ability of anti-repeater jamming is emphatically analyzed, and the results at different signal-to-noise ratio(SNR) show a strong anti-repeater jamming ability and range resolution that the proposed method possesses. Furthermore, the anti-repeater jamming ability is influenced by processing gain, bit error rate(BER) and correlation function. The simulation result validates the theoretical analysis, it shows the proposed method can significantly improve the anti-repeater jamming ability of a PD fuze.

关键词： Pulse Doppler fuze ID Chaotic binary code Encryption Repeater jamming

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意蜂工蜂酸性磷酸酶的分离纯化及动力学研究

四川大学学报（自然科学版） 2001年第5期38卷 776-780页

作者：江琰刘克武杨守忠张洪渊魏炜赵欣平刘晓雯闵丽娥张斌喻东四川大学生命科学学院成都610064

Acid phosphatase (ACPase, E.C.3.***.3.2) was isolated and purified from Apis cerana, and properties of the enzyme had been studied. The fresh bee pupa,honey,royal jelly and Apis cerana with wings cut were homogenized, acid treated to pH 5.0, then compared the ACPase activities of the four kinds of the homogenate. The Acid phosphatase was partially obtained Apis cerana by homogenate, ammunium sulfate fractionation and gel filtration with Sephadex G *** purified enzyme moved as a single electrophoretic band in PAGE. The purification multiple was 16.54,and the specific activity was 3.47U/*** with pNPP as its substrate. The optimum pH value for the enzymes was pH 4.1. The optomum temperature was about 50℃. The Michaelis Menten constant ( K m ) was 2.32×10 -4 mol/L on the pNPP. The ACPase was activated by Zn 2+ ,Mg 2+ and K +,while inhibited by ions of Cu 2+ ,Fe 3+ and Cr 3+ . Pb 2+ in low concentration activated the enzyme and in high concentration inhibited *** ACPase is inactivated by urea.

关键词：意蜂工蜂酸性磷酸酶分离纯化动力学蜜蜂

Electrochemical behavior of tungsten in(NaCl–KCl–NaF–WO_3)molten salt

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Rare Metals 2013年第5期32卷 512-517页

作者： Jie Li xin-Yu Zhang Ya-Bin liu Yun-Gang Li Ri-ping liu Key Laboratory of Metastable Materials Science & Technology Yanshan University Key Laboratory of the Ministry of Education for Modern Metallurgy Technology College of Metallurgy & Energy Hebei United University

Abstract The electrochemical reaction mechanism and electrocrystaUization process of tungsten in the NaCl- KCl-NaF-WO3 molten salt were investigated at 973 K （700℃） by means of cyclic voltammetry, chronopotentiometry, and chronoamperometry techniques. The results show that the electrochemical reaction process of tungsten in the NaCl-KCl-NaF-WO3 molten salt system is a quasireversible process mix-controlled by ion diffusion rate and electron transport rate. Tungsten ion in this system is reduced to W（0） in two steps. The electrocrystallization process of tungsten is found to be an instantaneous, hemispheroid three-dimensional nucleation process and the tungsten ion diffusion coefficient of 2.361 × 10^-4 cm2.s^-1 is obtained at experimental conditions.

关键词： NaCl-KClNaF-WO3 Tungsten Electrochemical reduction mechanism Electrocrystallization process