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Preparation and characterization of nanostructured Al_2._3-13wt.%TiO_2.ceramic coatings by plasma spraying

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Rare Metals 2009年第5期28卷 465-470页

作者： WANG Dongsheng TIAN Zongjun SHEN Lida LIU Zhidong HUANG Yinhui Jiangsu Key Laboratory of Precision and Micro-Manufacturing technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China college of Mechanical and Electrical engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Nanostructured and conventional Al2.3-13wt.%TiO2.ceramic coatings were prepared by plasma spraying with nanostructured agglomerated and conventional powders, respectively. The microstructure and microhardness of the coatings were investigated using scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, and microhardness measurement. Meanwhile, the friction and wear behaviors were analyzed and compared using a ball-on-disk tribometer. The results show that the conventional coating has lamellar stacking characteristic and has some pores. However, the nanostructured coating shows a bimodal microstructure, which is composed of both fully melted regions and partially melted regions. According to the microstructural difference, the partially melted regions can be divided into liquid-phase sintered regions （a three-dimensional net or skeleton-like structure： Al2.3-rich submicron particles embedded in the TiO2.rich matrix） and solid-phase sintered regions （remained nanoparticles）. The microstructural characteristics of the liquid-phase sintered region are formed due to the selective melting of TiO2.nanoparticles during plasma spraying. On the other hand, the TiO2.and Al2.3 nanoparticles of the solid-phase sintered regions are all unmelted during plasma spraying. Due to the existence of nanostructured microstructures, the nanostructured coating has a higher microhardness, a lower friction coefficient, and a better wear resistance than the conventional coating.

关键词： surface coating nanostructured coating plasma spraying microstructure microhardness wear resistance

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双脚标随机序列二次极值的密度函数的收敛

西南师范大学学报（自然科学版） 2004年第1期29卷 17-21页

作者：颜颖吴松林彭作祥西南师范大学数学与财经学院重庆400715 后勤工程学院基础部重庆400016

设{Xm,n;m,n≥1}为两个下标的独立同分布的随机序列,公共分布函数F(x)绝对连续.记Y(l)(m,n;k)为{Xm,n;m,n≥1}的第k个上极值之第l个二次极值.给出了Y(l)(m,n;k)的规范化密度函数在m→∞且n→∞和先m→∞后n→∞两种极限情形下收敛的充... 详细信息

设{Xm,n;m,n≥1}为两个下标的独立同分布的随机序列,公共分布函数F(x)绝对连续.记Y(l)(m,n;k)为{Xm,n;m,n≥1}的第k个上极值之第l个二次极值.给出了Y(l)(m,n;k)的规范化密度函数在m→∞且n→∞和先m→∞后n→∞两种极限情形下收敛的充要条件,并且给出了先n→∞后m→∞时Y(l)(m,n;k)的规范化密度函数收敛的充分条件.

关键词：双脚标随机序列二次极值密度函数密度收敛极限

Microstructure and Formation Mechanism of Aluminized Coatings on Nickel-based Superalloys

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Microstructure and Formation Mechanism of Aluminized Coating...

Fifth International Conference on Surface engineering

作者： Jibin Pei Liwen Zhang Jing Niu Quanzhong Zhang School of materials science and {2. Dalian university of technology Dalian Liaoning 116085 china

Aluminized coatings prepared on nickel-based superalloys can provide good protection against high temperature oxidation and hot *** study investigated the simple aluminized and silicon-aluminized coatings on nickel-based superalloy *** simple aluminized coating was prepared by pack cementation and the Al-Si coating was prepared by slurry aluminizing,*** microstructure of simple aluminized and Al-Si coating was analyzed by means of scanning electron microscope（SEM）,X-ray diffraction（XRD） and electron probe microanalysis（EPMA）.And the formation mechanism of simple aluminized and Al-Si coatings was *** results showed that the simple aluminized coating was about 49 um thick and consisted of three *** outer layer mainly consisted of Al-rich β-*** intermediate layer consisted of Ni-rich β-NiAl and *** inner diffusion layer consisted of Cr-rich and γ’-*** microstructure of Al-Si coating showed that the coating was about 70 um thick and consisted of five *** Al-Si coating consisted of CrxSiy,Al-rich β-NiAl,Ni-rich β-NiAl,Cr-rich and γ’-*** microstructure of simple aluminized coating was compared with that of Al-Si coating in order to find out the effect of *** to the effect of Si,there was a Transition layer in Al-Si *** Al-Si coating was thicker than simple aluminized *** declining trend of the aluminum concentration in the Al-Si coating was smoother than that of the simple aluminized coating.

关键词： nickel-based superalloys simple aluminized silicon-aluminized microstructure formation mechanism

Effects of Cinnamon Acid on Respiratory Rate and Its Related Enzymes Activity in Roots of Seedlings of Malus hupehensis Rehd.

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Agricultural sciences in china 2010年第6期9卷 833-839页

作者： GAO Xiang-bin,ZHAO Feng-xia,SHEN Xiang,HU Yan-li,HAO Yun-hong,YANG Shu-quan,SU Li-tao and MAO Zhi-quan State Key Laboratory of Crop Biology/college of Horticultural science and {2.,Shandong Agricultural university,Tai’an 2.1018,P.R.china State Key Laboratory of Crop Biology/college of Horticultural science and {2. Shandong Agricultural University Tai'an 271018 P.R.China

This paper studied the effects of cinnamon acid treatments on the respiratory rate and related enzymes activity in the seedling roots of Malus hupehensis *** would provide information for understanding the mechanisms of inhibition damage caused by continuous cultivation of apple tree.2. mL of solution containing different concentrations of cinnamon acid was added into container with the tested *** treatment,the samples were taken periodically and the respiratory rates were measured by OXY-LAB oxygen electrodes under 2.°C stable temperature and then the activities of related enzymes were *** rates of total respiration and other 2.pathways [tricarboxylic acid cycle （TCA） and pentose phosphate pathway （PPP）] appeared initially an increasing treads and late （on the 3rd d） began to ***,they again appeared an increase trend at the end period,on the contrast,the respiratory rate of embden-meyer- hot-parnas （EMP） pathway appeared a stead decline tread but it had a recover on the last *** respiratory rate of total and 3 pathways were decreased under 12. mg kg-1 （soil）.The dynamic trends of the enzymes activities of pyrophosphate-dependent phosphofructokinase （PFK）,glucose-6-phosphate dehydrogenase （G-6-PDH） and malate dehydrogenase （MDH） showed *** conclusion,treatments of certain concentration of cinnamon acid would inhibit the respiratory rate and related enzymes activity of roots of *** *** the inhibition degrees were positively related with concentration of cinnamon acid treatments.

关键词： cinnamon acid Malus hupehensis Rehd. roots respiratory rate enzymes activity

THE PROGRESS OF POTENTIAL-pH DIAGRAMS FOR V-H2. SYSTEM

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THE PROGRESS OF POTENTIAL-pH DIAGRAMS FOR V-H2O SYSTEM

第15届溶解度现象及相关相平衡过程国际会议

作者： Zhao 1 2.X.Y.and Zeng 1 2.Y.1 college of materials and Chemistry & Chemical {2. Chengdu university of technology Chengdu 610059 P.R.china 2.Mineral Resources Chemistry Key Laboratory of the Higher Education Institutions of Sichuan Province Chengdu 610059 P.R.china

＜正＞The potential-pH diagram was first proposed by Belgium corrosion scientist professor Pourbaix M in 1938. [1] All kinds of potential-pH diagram are thermo-dynamical tools,providing informations about the equilibr...

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Heterogeneous reactions of SO_2.on ZnO particle surfaces

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science china Chemistry 2011年第1期54卷 161-166页

作者： LI Jia,SHANG Jing & ZHU Tong State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental sciences and {2.,Peking university,Beijing 100871,china State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental sciences and {2. Peking University Beijing China

Heterogeneous reactions of SO2.on ZnO particle surfaces were studied using in situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS）. The influences of relative humidity （RH） and UV radiation （2. 365 nm） were investigated. In the absence of UV radiation, sulfite was the prominent product on the particle surfaces, and a negative relationship between RH and sulfite production was observed. In the presence of UV radiation, infrared （IR） absorption of sulfite and sulfate was evident in the spectra. With increasing RH or UV intensity, sulfite was gradually transformed into sulfate. UV intensity and RH exhibited a synergistic effect on the heterogeneous oxidation of SO2.on ZnO. On dry particles and with no UV radiation, the reaction order of SO2.on ZnO particles was 1.6. The initial uptake coefficient for the formation of sulfite, using the Brunauer-Emmett-Teller （BET） area as the reactive surface area of SO2. was 4.87 × 10^-6. At 40% RH and with UV radiation, the reaction order was 0.91, and the initial uptake coefficient was 2.2. ×10^-5.

关键词： SO2 ZnO DRIFTS heterogeneous oxidation UV radiation

A Grey Method of Prioritizing engineering Characteristics in QFD

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A Grey Method of Prioritizing Engineering Characteristics in...

2.09中国控制与决策会议

作者： Zhaoling Li~(1,2. Dongling Zhang~2.Qisheng Gao~2.1.college of Information science & {2.,Qingdao Univ.of science & {2.,2.6061,P.R.china 2.Institute of Complexity science,QingDao Univ.,QingDao 2.6071,P.R.china

＜正＞Quality function deployment（QFD） is a planning and problem-solving tool that is gaining acceptance for translating customer requirements into the engineering characteristics of a *** the rating order of engineering characteristics from input variables is a crucial step in applying QFD.A grey method is proposed to prioritize engineering *** engineering characteristics are considered to be comparability sequences, while the customer requirements in customer competitive analysis are considered to be reference *** QFD can be regarded as a grey system and the relationships between the customer requirements and engineering characteristic can be determined with the grey relational *** grey superior analysis is used to prioritize the engineering *** example of the door design of an automobile is used to demonstrate the application of the proposed approach.

关键词： Quality Function Deployment House of Quality Prioritizing engineering Characteristic Grey Relational Analysis

非均相体系中二茂铁对中间相碳微球形成的影响及机理分析

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天津大学学报 2006年第B6期39卷 176-180页

作者：刘秀军赵乃勤王成扬天津大学材料科学与工程学院

在QI含量较高的煤焦油沥青中加入一定量的二茂铁,在42.℃下反应7h,得到了具有反Brooks-Taylor结构的中间相碳微球(MCMB)．X-射线衍射(XRD)分析结果表明,二茂铁的加入促进了热缩聚反应,使微晶的堆层厚度及堆积层数增加．通过扫描电镜(SEM... 详细信息

在QI含量较高的煤焦油沥青中加入一定量的二茂铁,在42.℃下反应7h,得到了具有反Brooks-Taylor结构的中间相碳微球(MCMB)．X-射线衍射(XRD)分析结果表明,二茂铁的加入促进了热缩聚反应,使微晶的堆层厚度及堆积层数增加．通过扫描电镜(SEM)对中间相碳微球的形貌观察及结构分析,提出了在非均相体系中中间相碳微球的成核及长大机理．认为中间相碳微球的长大要经过一层固体颗拉形成的屏障．

关键词：中间相碳微球二茂铁 SEM 机理

Neural Network Adaptive Sliding Mode Control to Seesaw Systems

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Neural Network Adaptive Sliding Mode Control to Seesaw Syste...

第二十九届中国控制会议

作者： FAN Zhiyong,ZHANG Jinggang college of Electronic Information engineering,Taiyuan {2. of science and technology,Taiyuan 03002.,P.R.china

In this paper,a neural network adaptive sliding-mode controller(NNASMC)is proposed for higher-order,nonlinear seesaw *** first,the mathematical model of the seesaw system is ***,the neural network sliding mode controller is designed to be the main controller,which is used to approach the equivalent control part of sliding mode *** adaptive sliding mode controller is the compensation controller of the system,and the interference and uncertainties of the system are compensated by ***,sliding mode control based on index reaching law and NNASMC are used to do simulation on a seesaw system *** simulation results show that the NNASMC converges very fast and the maximum deviation of the system is very small.

关键词： Seesaw Neural Network Adaptive Sliding-mode Chattering