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Journal of Environmental Sciences 2003年第6期15卷 854-858页

作者： CHEN Su-hua, ZHOU Qi-xing, SUN Tie-heng, LI Pei-jun (institute of Applied Ecology, Chinese Academy of Sciences, shenyang 110016, china. institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

Quick, simple to perform, and cheap biomarkers were combined in a rapid assessment approach to measure the effects of metal pollutants, Cu, Cd, Pb and Zn in meadow burozem on wheat. Analysis of orthogonal design showed that the significant zinc factor indicated both the inhibition rate of shoot mass and that of root elongation were affected by zinc(P<0.05 and P<0.01, respectively). The first toxicity canonical variable (TOXI), formed from the toxicity data set, explained 49% of the total variance in the toxicity data set; the first biological canonical variable(BIOL) explained 42% of the total variation in the biological data set. The correlation between the first canonical variables TOXI and BIOL (canonical correlation) was 0.94 (P<0.0001). Therefore, it is reliable and feasible to use the achievement to assess toxicity of heavy metal combined polluted soil using canonical analysis. Toxicity of soil combined polluted by heavy metals to plant community was estimated by comparing the IC 50 values describing the concentration needed to cause 50% decrease with grow rate compared to no metal addition. Environmental quality standard for soils prescribe that all these tested concentration of heavy metals in soil should not cause hazard and pollution ultimately, whereas it indicated that the soils in second grade cause more or less than 50% inhibition rates of wheat growth. So environmental quality standard for soils can be modified to include other features.

关键词： heavy metal combined pollution ecological toxicity canonical analysis

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轮式移动机器人沙地行驶控制建模与仿真研究

系统仿真学报 2008年第18期20卷 5035-5039页

作者：谷侃锋赵明扬中国科学院沈阳自动化研究所沈阳现代装备研究设计中心

结合车轮沙土相互作用的力学分析,研究解决轮式移动机器人沙地行驶车轮过度滑转下陷问题。考虑纵列式重复通过车轮沙土力学参数的修正,建立六轮式沙地移动机器人的动力学模型,以车轮滑转率为状态变量,设计了移动机器人沙地行驶的滑模驱... 详细信息

结合车轮沙土相互作用的力学分析,研究解决轮式移动机器人沙地行驶车轮过度滑转下陷问题。考虑纵列式重复通过车轮沙土力学参数的修正,建立六轮式沙地移动机器人的动力学模型,以车轮滑转率为状态变量,设计了移动机器人沙地行驶的滑模驱动控制器跟踪车轮期望滑转率。MATLAB/Simulink仿真结果表明,采用该控制器可以较快地跟踪期望滑转率,有效地限制机器人车轮的滑转,避免车轮的过度下陷。

关键词：移动机器人车轮下陷滑转率沙地滑模控制 Simulink仿真

Influence of rotating magnetic field on cerebral infarction volume, cerebral edema and free radicals metabolism after cerebral ischemia/reperfusion injury in rats

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Neural Regeneration research 2006年第9期1卷 777-780页

作者： Xiaohong Liu1, Zhiqiang Zhang2, Lixin Zhang3 1Liaoning Disabled Children’s Rehabilitation Center, shenyang 110015, Liaoning Province, china 2Department of Rehabilitation, Second Hospital Affiliated to china Medical University, shenyang 110003, Liaoning Province, china 3Department of Rehabilitation and Physiotherapy, First Hospital Affiliated to china Medical University, shenyang 110001, Liaoning Province, china Liaoning Disabled Children's Rehabilitation Center Shenyang 110015 Liaoning Province China Department of Rehabilitation China Medical University Shenyang 110003 Liaoning Province China Department of Rehabilitation and Physiotherapy China Medical University Shenyang 110001 Liaoning Province China

BACKGROUND: It has shown that magnetic field can improve blood circulation, decrease blood viscosity, inhibit free radicals, affect Ca2+ flow in nerve cells, control inflammatory and immunological reaction, and accelerate nerve cell regeneration. In addition, protective effect of magnetic field, which acts as an iatrophysics, on ischemic brain tissues has been understood gradually. OBJECTIVE: To investigate the effects of rotating magnetic field (RMF) on volume of cerebral infarction, cerebral edema and metabolism of free radicals in rats after cerebral ischemia/reperfusion injury. design: Randomized controlled animal study. SETTING: Rehabilitation Center of disabled children, Liaoniang; Department of Rehabilitation, the Second Affiliated Hospital, china Medical University; Department of Rehabilitation Physiotherapy, the First Affiliated Hospital, china Medical University. MATERIALS: A total of 70 healthy Wistar rats aged 18-20 weeks of both genders were selected and randomly divided into 3 groups: sham operation group with 12 rats, control group with 20 rats and treatment group with 38 rats. The treatment group included 4 time points: immediate reperfusion with 6 ones, 6-hour reperfusion with 20 ones, 12-hour reperfusion with 6 ones and 18-hour reperfusion with 6 rats. Main instruments were detailed as follows: magnetic head of rotating magnetic device was 6 cm in diameter; magnetic induction intensity at the surface of magnetic head was 0.25 T in silence; the maximal magnetic induction intensity was 0.09 T at the phase of rotation; the average rotating speed was 2500 r per minute. METHODS: The experiment was carried out in the china Medical University in March 2003. Focal cerebral ischemic animal models were established with modified Longa’s method. Operation was the same in the sham operation, but the thread was inserted as 10 mm. Neurologic impairment was assessed with 5-rating method to screen out cases. Those survivals with grade 1 and grade 2 after ischemia f

关键词： cerebral edema and free radicals metabolism after cerebral ischemia/reperfusion injury in rats free

design　AND　PREPARATION　OF　SILICON　NITRIDE　COMPOSITE　WITH　HIGH　FRACTURE　TOUGHNESS　AND　NACRE　STRUCTURE

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 479-484页

作者： Y Huang H.N Hao Y.L. Chen and B.L.Zhou (1)Department of Materials Science and Engineering, Tsinghua University,Beijing 100084, china 2)institute of Metal research, Chinese Academy of Sciences,shenyang 110015, china ) Tsinghua Univ Beijing China

A new way of designing and preparing silicon nitride ceramic composite with high fracture toughness and nacre structure has been proposed. To mimic the laminated structure of nacre, Si_3N_4 matrix ceramic layer can be obtained through compacting rolling method. To mimic the secondary toughening of nacre structure, SiC whisker is added into Si_3N_4 and acts as the secondary toughening phase. Boron nitride (BN)is selected to mimic the organic layer in nacre so as to form the weak interfaces between Si_3N_4 layers. Alumina is added into BN to adjust the bonding strength of the *** Si_3N_4 sheets are stacked into the die after coating with BN. After the removal of the organic matter in them, the green body is hot pressed at 1820℃for 1.5 hours under N_2 atmosphere. The fracture toughness of the so-made Si_3N_4 composite at room temperature is 20.36MPa m￣(1/2), the three-point bending strength at room temperature is 651.47MPa. The crack spreads and deflects along the interface between BN and Si_3N_4 layer and extends through the BN layer into Si_3N_4 layer. The improvement of the fracture toughness may be due to the staircase-shape-like crack which provides the long crack path, the fracture and deformation of Si_3N_4 layer, and the pullout of SiC whiskers from the Si_3N_4 layer.

关键词： secondary toughening,compact rolling silicon nitride nacre Structure

LANDSCAPE ECOLOGICAL CONSTRUCTION IN RURAL china:THEORY AND APPLICATION

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Chinese Geographical Science 2001年第2期11卷 104-114页

作者： XIAO Du-ning (Cold and Arid Regions Environmental and Engineering research institute, the Chinese Academy of Sciences, Lanzhou 730000, P.R.china institute of Applied Ecology,the Chinese Academy of Sciences, shenyang 110015,P.R.china ) Cold and Arid Regions Environmental and Engineering research institute the Chinese Academy of Sciences Lanzhou P.R. China institute of Applied Ecology the Chinese Academy of Sciences Shenyang P. R. China

In landscape with overpopulation, intensive management for economic production, and where even small natural-vegetation patches are scarce, ecological conservation generally must be developed in the course of economic development. Thus “landscape ecological construction” has evolved in china. This approach adds spatial elements and alters landscape pattern to strengthen inter-ecosystem linkages, improve functioning of damaged ecosystems, and increase productivity and stability of the whole landscape. Five examples of managed landscapes in china are presented: dike-pond systems in a river delta; multi-pond system in a rice paddy landscape; field-grass-wood grid system on unstable sand dunes; shelterbelt network in a crop field area; and field-grass-wood mosaic system on highly erodible hilly farmland. These indicate that ecological conditions can be improved along with increased economic production. Altering landscape structure and ecological flows by introducing small landscape elements in distinct spatial patterns is considered a key to the results. This reshaping of the land has focused on changing patch size, regularity of arrangement, biological and hydrological corridors, and networks, the matrix and grain size. It suggests that such changes can increase negative feedbacks and increase stability. Finally, planning and design principles are pinpointed for the landscape ecological construction process.

关键词： landscape planning ecological construction rural china

Simulation of Tensile Behavior of Nickel Foam

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稀有金属材料与工程 2011年第S3期40卷 224-227页

作者： Zhao Mingjuan 1, Zhang Xiaolan 1, Zhao Longzhi 1,3, Zhang Jinsong 2 1 Key Laboratory of Ministry of Education for Conveyance and Equipment, East china Jiaotong University, Nanchang 330013, china 2 institute of Metal research, Chinese Academy of Sciences, shenyang 110016, china 3 Key Laboratory of Superlight Materials & Surface Technology, Ministry of Education, Harbin Engineering University, Harbin 150001, china E china Jiaotong Univ Key Lab Minist Educ Conveyance & Equipment Nanchang 330013 Peoples R China Harbin Engn Univ Minist Educ Key Lab Supertight Mat & Surface Technol Harbin 150001 Peoples R China Chinese Acad Sci Inst Met Res Shenyang 110016 Peoples R China

Nickel foam is widely used as the electrode, the catalyst carrier, sound absorption material and other application fields. The tensile behavior of the open cell nickel foam which is one of the most important parameters in the design process was investigated with the finite element method based on ANSYS software in this paper. The effects of strain rates and temperature on the yield strength of the nickel foam were obtained. The results show that the yield strength exhibit a nonlinear reduction with the increases of the temperature for the elastic bending of the struts of the reinforcement grew quickly depending on the temperature. However, the yield strength increases slowly with the improvement of the strain rate because the strain rate neither change the internal structure and properties such as the porosity and the aperture, nor alter the external circumstance in order to change the internal properties such as the temperature. The results of the simulation accord with those of the experiments, which is very important to understand the tensile behavior of the foam materials.

关键词： nickel foam ANSYS yield strength temperature strain rate

An Intelligent design of Electron Lens System

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Journal of Systems Engineering and Electronics 1996年第1期7卷 75-86页

作者： Let Wei Tong Linsu & Wu Shengli (Electronic Engineering Department of Southeast University, Naming 210096, P. R. china) (shenyang aircraft Manufacture Company) Electronic Engineering Department of Southeast University Nanjing 210096 P. R. China shenyang aircraft Manufacture Company

At present, the main work of electron optical system CAD is solving equations and calculating mumerical values. However, the design perhaps needs more inference and expertise than numerical calculations because the structure of electron lens system is complicated. In this paper, a primary expert system is applied to design the electron lens system intelligently. This expert system is combined with SEU-3D program which is used to simulate the electron optical system to optimize the electron lens systems. In spite of this, the expert system which is established in this paper can also be used to diagnose the electron lens system. Although the knowledge base is small and rules are not abundant, this paper has used this system to obtain some very useful results. The initial success with this system suggests that further work need to be done whether more rules and knowledge will be added to extend the ability of expert system.

关键词： Intelligent design of electron lens system Expert system Knowledge base. SEU-3D Program

基于OpenMV摄像头的运动目标控制与自动追踪系统设计与实现

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现代电子技术 2024年第17期47卷 166-172页

作者：徐涢基王峥邹佳民王燊炀方健南昌交通学院交通运输学院江西南昌330100 南昌大学江西省机器人与焊接自动化重点实验室江西南昌330031

针对运动目标自动追踪系统复杂且成本较高等问题,文中旨在设计一种成本低廉且易于部署的基于STM32F103C8T6、OpenMV摄像头和二维舵机云台的运动目标自动追踪系统,以解决传统自动追踪系统设备昂贵、算法复杂难于推广的问题,并为OpenMV摄... 详细信息

针对运动目标自动追踪系统复杂且成本较高等问题,文中旨在设计一种成本低廉且易于部署的基于STM32F103C8T6、OpenMV摄像头和二维舵机云台的运动目标自动追踪系统,以解决传统自动追踪系统设备昂贵、算法复杂难于推广的问题,并为OpenMV摄像头在安防监控等领域的应用提供新的思路。该系统主要由主控模块、OpenMV摄像头模块、二维舵机云台模块、电源模块、OLED显示模块组成,通过OpenMV摄像头模块识别特定阈值的色块或矩形图形,并处理色块与矩形角点位置信息,将处理后的数据通过串口通信发送给主控模块,再由主控模块通过PID算法与运动算法控制二维舵机云台模块运动,从而实现运动控制与自动追踪。最后通过激光笔测试装置实际追踪效果,整合数据进行分析验证,该运动目标控制与自动追踪系统的理论研究与设计能够达到目标效果。

关键词： OpenMV摄像头运动目标控制自动追踪系统 STM32F103C8T6 二维云台颜色识别 OLED PID

维普期刊数据库博看期刊

NUMERICAL COMPUTATION OF TWO-PHASE TURBULENT COMBUSTION PROCESSES

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Chinese Journal of Aeronautics 1988年第1期 27-33页

作者： Zhou Xiaoqing shenyang Aeroengine research institute

A self-compiled computer code GEMCHIP is briefly *** of this method to several typicalcombustor flows is *** design and Development of air-breathing

关键词： NUMERICAL COMPUTATION OF TWO-PHASE TURBULENT COMBUSTION PROCESSES UI