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Research on Cooling Effect with Coolant Groove Structure Parameters in Platelet Transpiration Cooled Nosetip

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Journal of Thermal Science 2010年第5期19卷 438-444页

作者： RONG Yisheng and LIU Weiqiang college of Aerospace and Material engineering,National Univ.of Defense technology,Changsha 410073,china college of Aerospace and Material engineering National Univ. of Defense Technology Changsha China

A platelet transpiration cooled nosetip is considered as thermal protection system （TPS） to prevent hypersonic ve- hicle from the serious aerodynamic heating. Based on the one dimensional flow model, a distribution model of coolant is proposed for the temperature calculation. When Si = Sj （i, j=1,… 24）, the first cooling effect parameter Pmax is proposed and its relationship with total mass flux and Sc0/Si is investigated. The result shows that Pmax increases while the total mass flux increases, and when the mass flux is fixed, Pmax increases rapidly at the be- ginning and then turns to a nearly stable value while Sc0/Si increases. Then under the precondition of cooling ef- fect, we fix Sc0/Si to insure there is enough space for the pipe. Numerical investigation shows the design of the nosetip makes the transpiration cooling extremely effective. In order to reduce the temperature difference on the nosetip, the second cooling effect parameter Pdiff is proposed and different Pdiff with different 0gi （i=1,..., 23） are analyzed. According to the cases we design, Pdiff decreases while the upstream 0gi decreases or the down- stream 0gi increases. The best result among cases shows Pdiff is reduced by 15.1%.

关键词： platelet transpiration cooling nosetip thermal protection system aerodynamic heating

RBF neural network and active circles based algorithm for contours extraction

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Progress in Natural Science:Materials International 2007年第6期17卷 681-686页

作者： Zhou Zhiheng, Zeng Delu and Xie Shengli(college of Electronic & Information engineering, South china University of technology, Guangzhou 510640, china) college of Electronic and Information engineering South China University of Technology Guangzhou 510640 China

For the contours extraction from the images, active contour model and self-organizing map based approach are popular nowadays. But they are still confronted with the problems that the optimization of energy function will trap in local minimums and the contour evolutions greatly depend on the initial contour selection. Addressing to these problems, a contours extraction algorithm based on RBF neural network is proposed here. A series of circles with adaptive radius and center is firstly used to search image feature points that are scattered enough. After the feature points are clustered, a group of radial basis functions are constructed. Using the pixels’ intensities and gradients as the input vector, the final object contour can be obtained by the predicting ability of the neural network. The RBF neural network based algorithm is tested on three kinds of images, such as changing topology, complicated background, and blurring or noisy boundary. Simulation results show that the proposed algorithm performs contours extraction greatly.

关键词： contours extraction RBF neural network dynamic clustering.

Series-based approximate approach of optimal tracking control for nonlinear systems with time-delay

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Progress in Natural Science:Materials International 2008年第12期18卷 1571-1576页

作者： Gongyou Tang~a Mingqu Fan~(a,b) a college of Information Science and engineering,Ocean University of china,Qingdao 266100,china b college of Information and engineering,Shandong University of Science and technology,Jinan 250031,china [a]college of Information Science and engineering Ocean University of China Qingdao 266100 China [b]college of Information and engineering Shandong University of Science and Technology Jinan 250031 China

The optimal output tracking control (OTC) problem for nonlinear systems with time-delay is *** a series-based approx- imate approach,the original OTC problem is transformed into iteration solving linear two-point boundary value problems without time- *** OTC law obtained consists of analytical linear feedback and feedforward terms and a nonlinear compensation term with an infinite series of the adjoint *** truncating a finite sum of the adjoint vector series,an approximate optimal tracking control law is obtained.A reduced-order reference input observer is constructed to make the feedforward term physically *** exam- ples are used to test the validity of the series-based approximate approach.

关键词： Nonlinear systems Time-delay Tracking control Optimal control Observer

Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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Science china(Technological Sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2 & XU WeiSheng 2 1 college of Hydraulic and Environmental engineering,china Three Gorges University,Yichang 443002,china 2 college of Hydropower engineering,Xi’an University of technology,Xi’an 710048,china 1. college of Hydraulic and Environmental engineering China Three Gorges University Yichang 443002 China2. College of Hydropower Engineering Xi’an University of Technology Xi’an 710048 China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

LA-ICP-MS dating of Zhangjiakou Formation volcanic rocks in the Zhangjiakou region and its geological significance

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Progress in Natural Science:Materials International 2008年第8期18卷 975-981页

作者： Hong Zhang a,b,*, Mingxin Wang a, Xiaoming Liu b a college of Mechanical and Energy engineering, Jiangsu Polytechnic University, Baiyun District, changzhou, Jiangsu 213016, china b Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an 710069, china college of Mechanical and Energy engineering Jiangsu Polytechnic University Baiyun District Changzhou Jiangsu 213016 China Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China

The geological cross section of the Zhangjiakou Formation is originally established in the Zhangjiakou region. From the dating of four samples from typical cross sections of the Zhangjiakou Formation in the Zhangjiakou region, the age range is found to be mainly from 143.0 ± 3.7 Myr to 136.1 ± 1.4 Myr, which almost equals the sum of the age range of the Zhangjiakou Formation (136-135 Myr) and that of the Tuchengzi Formation (143-136 Myr) in the Luanping region, and the Zhangjiakou and Tuchengzi Formations in Zhangjiakou-Luanping of North Hebei are found to be conformable. The evidence above indicates that the Zhangjiakou and Tuchengzi Formations, which are distributed in Zhangjiakou-Luanping, were formed under the same geological setting. Volcanic activity was earlier and longer (143-136 Myr) in the western region (Zhangjiakou) than that in the eastern region (Luanping). The "Zhangjiakou Formation"in Chengde and Pingquan formed in the period in which the Yixian Formation in West Liaoning formed, so should be renamed the Yixian Formation.

关键词： Zhangjiakou Formation Volcanic rocks LA-ICP-MS Dating Zhangjiakou region

DIFFUSIVITY OF RARE EARTHS IN POROUS ION EXCHANGERS IN EDTA SOLUTION

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Chinese Journal of Reactive Polymers 1992年第1期1卷 1-10页

作者： LING Daren, and XIE WeijieDepartmant of Organic Chemical engineering,Jiangsu Chemical technology institute, changzhou 213016, china

The self-diffusion of RE isotopes in porous cation exchangers with various particle size and in several MR-type resins n EDTA solutions of rare earths was *** intraparticle effective diffusivities De of Ce,Tb and Yb were measured by isotopic ion exchange,De was affected by the concentration of the bulk solution and was separated into a solid phase diffusivity Dg and a macropore diffusivity Dp using Kataoka′s didisperse pore model. It shows that the model can be applied to express the kinetic process;De much larger than De and Dg is nearly equal to De. Solid phase resistance is a major component of resistance to the exchange for porous resins.

关键词：多孔离子交换乙二胺四乙酸溶液稀土族扩散性扩散系数

Particle swarm optimization with a leader and followers

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Progress in Natural Science:Materials International 2008年第11期18卷 1437-1443页

作者： Junwei Wang Dingwei Wang institute of Systems engineering,college of Information Science and engineering,Northeastern University,Shenyang 110004,china institute of Systems engineering College of Information Science and Engineering Northeastern University Shenyang 110004 China

Referring to the flight mechanism of wild goose flock,we propose a novel version of Particle Swarm Optimization(PSO)with a leader and *** is referred to as Goose Team Optimization(GTO).The basic features of goose team flight such as goose role division, parallel principle,aggregate principle and separate principle are implemented in the recommended *** GTO,a team is formed by the particles with a leader and some *** role of the leader is to determine the search *** followers decide their flying modes according to their distances to the leader ***,a wide area can be explored and the particle collision can be really *** GTO is applied to four benchmark examples of complex nonlinear functions,it has a better computation perfor- mance than the standard PSO.

关键词： Particle swarm optimization Goose team optimization Role division Parallel principle Aggregate principle Separate principle

Further study of sources of the imported cobalt-blue pigment used on Jingdezhen porcelain from late 13 to early 15 centuries

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Science china(Technological Sciences) 2008年第3期51卷 249-259页

作者： DU Feng1 & SU BaoRu2 1 institute of Chemistry & Molecular engineering, Qingdao University of Science & technology, Qingdao 266000, china 2 college of Information Science technology, Qingdao University of Science & technology, Qingdao 266000, china institute of Chemistry & Molecular engineering Qingdao University of Science & Technology Qingdao 266000 China college of Information Science technology Qingdao University of Science & Technology Qingdao 266000 China

Based on the conclusion of modern scientific analysis: the cobalt-blue pigment applied on Jingdezhen official porcelain during Yuan Dynasty and prior to Xuande reign of Ming Dynasty (1271―1425) contains high iron and low manganese con- tents, and the cobalt during Xuande and after Xuande periods (after 1426) of Ming Dynasty contains high manganese and low iron contents, in combination with the traditional archaeological method, the related historical textual records were in- vestigated and analyzed, the imported cobalt employed on Jingdezhen official porcelain was studied comprehensively, systematically and logically. In fact, 'Su Ma Li Qing' (Samarra-blue) and 'Su Bo Ni Qing' (Sumatra-blue) are definitely different cobalt ores originated in different places, because of their very similar translitera- tions in Chinese, the confusion has appeared in ancient books for more than 400 years, which considered 'Su Ma Li Qing' and 'Su Bo Ni Qing' as the same co- balt-blue pigment. In this article the mistake was corrected, the possible producing places and the approximate eras of the two pigments imported to china and used at Jingdezhen were also suggested.

关键词： imported cobalt-blue pigments employed on official blue-and-white porcelain Yuan Dynasty early Ming Dy- nasty Mn/Fe content ratio Su Ma Li Qing (Samarra-blue) Su Bo Ni Qing (Sumatra-blue) scientific archae- ological research transliteration

Preparation of grain size controlled boron-doped diamond thin films and their applications in selective detection of glucose in basic solutions

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Science china Chemistry 2010年第6期53卷 1378-1384页

作者： ZHAO JianWen1,2,WANG JinLiang3,ZHI JinFang3 & ZHANG ZhiMing4 1college of Chemistry and Chemical engineering,Jishou University,Jishou 416000,china 2Schools of Materials Science and engineering,Nanyang Technological University,639798,Singapore 3Laboratory of Organic optoelectronic Functional Materials and Molecular engineering,Technical institute of Physics and Chemistry & Graduate University of Chinese Academy of Sciences,Beijing 100080,china 4Research institute of Micro-Nano Science and technology,Shanghai Jiao Tong University,Shanghai 200030,china 1. college of Chemistry and Chemical engineering Jishou University Jishou 416000 China2. Schools of Materials Science and Engineering Nanyang Technological University 639798 Singapore Singapore3. Laboratory of Organic Optoelectronic Functional Materials and Molecular Engineering Technical Institute of Physics and Chemistry & Graduate University of Chinese Academy of Sciences Beijing 100080 China4. Research Institute of Micro-Nano Science and Technology Shanghai Jiao Tong University Shanghai 200030 China

Boron-doped diamond (BDD) thin films with different crystal grain sizes were prepared by controlling the reacting gas pressure using hot filament chemical vapor deposition (HFCVD).The morphologies and structures of the prepared diamond thin films were characterized by scanning electron microscopy (SEM) and Raman *** electrochemical responses of K4Fe(CN)6 on different BDD electrodes were *** results suggested that electron transfer was faster at the boron-doped nanocrystalline diamond (BDND) thin film electrodes in comparison with that at other BDD thin film *** prepared BDD thin film electrodes without any modification were used to directly detect glucose in the basic *** results showed that the as-prepared BDD thin film electrodes exhibited good selectivity for detecting glucose in the presence of ascorbic acid (AA) and uric acid (UA).The higher sensitivity was observed on the BDND thin film grown on the boron-doped microcrystalline diamond (BDMD) thin film surface,and the linear response range,sensitivity and the low detection limit were 0.25–10 mM,189.1 μA mmol-1 cm-2 and 25 μM (S/N=3) for glucose in the presence of AA and UA,respectively.

关键词： diamond thin films electrochemical properties selective glucose detection