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Rare Metals 1989年第2期9卷 58-63页

作者： Chen Huaxu Shao Guangdi Department of Chemistry,University of science and technology BeijingBai Linshan Department of Chemical Engineering,East china Institute of Metallurgy

In the presence of ethyl alcohol or emulsifier OP,molybdenum(Ⅵ) forms 1∶1∶1'water soluble colored coordination com- pound with both of 2-(2-thiazolylazo)-5-diethylaminophenol (abbreviation TAE) and *** deep blue coordination compound is inert characteristically and remains stable in 1.7 mol/L sulfuric acid,2.4 mol/L hydrochloric or ni- tric *** will not be decomposed by masking agents even on boiled,while in that case,almost all the colored coordination com- pounds formed by other metal ions will be decomposed *** inert character of the coordination compound of molybdenum(Ⅵ) and its utilization in improving the analytical selectivity have been *** the coexistence of various for- eign ions,especially in the presence of a great quantity of tungsten,which always interferes with the determination of molybdenum,the direct determination of molybdenum in the aqueous solution by applying this system has shown an acceptable sensitivity and *** the results of determination in some synthetic and standard samples,it seems feasible to use this system in the determination of molybdenum in nonferrous alloys.

关键词： and its Analytical Application Molybdenum Hydroxylamine Study on the Inert coordination compound in the System of TAE

A Hybrid Genetic Algorithm for Reduct of Attributes in Decision System Based on Rough Set Theory

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Wuhan University Journal of Natural sciences 2002年第3期7卷 285-289页

作者： Dai Jian\|hua 1,2 , Li Yuan\|xiang 1,2 ,Liu Qun 3 1. State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, Hubei,china 2. School of computer, Wuhan University, Wuhan 430072, Hubei, china 3. School of computer science, Lab. of Software Eng. Wuhan Univ. Wuhan 430072 China Sch. of comp. Wuhan Univ. Wuhan 430072 China Sch. of comp. Sci. Chongqing Univ. of Post and Telecom. Chongqing 400065 China

Knowledge reduction is an important issue when dealing with huge amounts of data. And it has been proved that computing the minimal reduct of decision system is NP-complete. By introducing heuristic information into genetic algorithm, we proposed a heuristic genetic algorithm. In the genetic algorithm, we constructed a new operator to maintaining the classification ability. The experiment shows that our algorithm is efficient and effective for minimal reduct, even for the special example that the simple heuristic algorithm can’t get the right result.

关键词： rough set reduction genetic algorithm heuristic algorithm

New method for signal encryption using blind source separation based on subband decomposition

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Progress in Natural science:Materials International 2008年第6期18卷 751-755页

作者： Zuyuan Yang*,Guoxu Zhou,Zongze Wu,Jinlong Zhang School of Electrics and Information Engineering,South china University of technology,Guangzhou 510641,china School of Electrics and Information Engineering South China University of Technology Guangzhou 510641 China

A novel cryptosystem based on subband decomposition independent component analysis(SDICA)is proposed in this work,where no assumption of independence for the ciphers and the plaintexts is *** the proposed cryptosystem,the encryption is asynchronous,*** plaintexts are mixed mutually firstly and then mixed with the *** addition,the decryption is asynchronous,such that the decryption accuracy of the plaintexts can be *** special information about the original mixing matrix is used for solving the indeterminacy of the permutation and scale of columns of the recovered mixing matrix in SDICA,instead of the characteristics of the *** are given to illustrate security and availability of our cryptosystem.

关键词： SDICA Signal encryption BSS

technology for Hybrid Pepper Seed Production in china

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Hunan Agricultural science ＆ technology Newsletter 2002年第2期3卷 17-19页

作者： Zou Xuexiao Huazhong University of science and technology, Wuhan 430074, china Huazhong University of science and technology Wuhan 430074 China

History of hybrid pepper seed production, the status of annually balanced production, and innovative techniques for the large-scale seed production in china are reviewed. Helped by the technological breakthroughs in t... 详细信息

关键词： pepper (Capsicum annuum L.) hybrid seed scale production.

A NEW METHOD FOR MEASURING OCEAN WAVE FROM SEASAT SAR REMOTE SENSING IMAGE

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Journal of Electronics(china) 1989年第4期6卷 320-326页

作者：孙京生刘政凯 University of science and technology of china Hefei

A new method for measuring ocean wave length and direction from SEASAT SyntheticAperture Radar (SAR)remote sensing image is presented in the paper. In the new method, an ocean waveimage is sampled in certain directions, the samples are then analyzed by using one dimensional FourierTransformation to calculate the ocean wave correlation function. Finally the ocean wave length and direc-tion are determined from the ocean wave correlation function. The new method is better than the tradition-al two-dimensional Fourier Transformation method in both consuming time and precision .

关键词： Ocean wave Synthetic aperture radar Remote sensing image Fourier transformation SEASAT

Enhancing aerodynamic performances of a high-turning compressor cascade via boundary layer suction

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science china(Technological sciences) 2010年第10期53卷 2748-2755页

作者： GUO Shuang1, CHEN ShaoWen1, LU HuaWei2, SONG YanPing1 & CHEN Fu1 1 School of Energy science and Engineering, Harbin Institute of technology, Harbin 150001, china 2 Marine Engineering college, Dalian Maritime University, Dalian 116026, china School of Energy science and Engineering Harbin Institute of Technology Harbin China Marine Engineering college Dalian Maritime University Dalian China

Experimental investigation was carried out to study the effect of suction positions and suction flow rates on the aerodynamic performance of a compressor cascade with a large camber angle. The ink-trace flow visualization was conducted and the flow fields of the cascade were also measured. Three types of boundary layer suction configurations are compared,i.e. the suction surface suction,the endwall suction and the compound suction. Experimental results show that the large amount of suction flow rate gains more losses reduction than the small amount for a certain proper suction configuration,but the speed of loss decline slows down as the suction flow rate goes on increasing. Boundary layer suction on the suction surface obviously enhances the ability of the boundary layer around the midspan to withstand the negative pressure gradient of the flow passage. The range of the suction surface corner is also decreased. If the suction slot locates in the corner separation region where severe separation has happened,the flow separation will be terminated at the slot and redevelop downstream. And boundary layer suction on the endwall mainly influences the endwall corner region in remarkably delaying,lessening and reorganizing the corner separation. While the whole flow field is remarkably improved at both midspan and the corner region in the compound suction schemes. At higher suction flow rates,the aerodynamic performance of the compressor cascade is better than that with boundary layer suction simply on the suction surface or on the endwall. When the suction flow rate is 1.5% of the inlet mass flow,the compound suction scheme achieves a maximum loss reduction of 17% compared with the cascade without boundary layer suction.

关键词： boundary layer suction high-turning diffusion cascade suction flow rate suction position experimental investigation

Extension theory and its application

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Chinese science Bulletin 1999年第17期44卷 1538-1548页

作者： CAI WenResearch Institute of Matter-Element Analysis , Guangdong University of technology , Guangzhou 510090, china Research Institute of Matter-Element Analysis Guangdong University of Technology Guangzhou China

The article Extension Set and Non-compatible Problems was published in 1983. It proclaimed the birth of extension theory. Its objects of study are contradictory problems in the realistic world; its theoretical pillars are matter element theory and extension set theory. Its basic methods are extension methods. Its practical methods are extension engineering methods,

关键词： extension theory matter element extension set.

coMPLEXITY science & MANAGEMENT

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Bulletin of the Chinese Academy of sciences 1999年第3期13卷 166-174页

作者： Cheng Siwei(Department of Management sciences, the National Natural science Foundation of china)

Ⅰ. science IS FACING A SHARP TURN complexity science is a new scientific category that made its debut in the 1980s. It is a newly emerging discipline concerning research into complexity itself, and its application to complex systems. Although it is still in its infancy, it has been hailed by some leading scientists as "the science for the 21st century."

关键词： coMPLEXITY science MANAGEMENT

Fabrication of copper (Ⅰ) nitride nanorods within SBA-15 by metal organic chemical vapor deposition

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science china(Technological sciences) 2009年第2期52卷 352-356页

作者： ZHANG Ying1,2, Frank Leung-Yuk Lam2, YAN ZiFeng1 & HU XiJun2 1 School of Chemistry & Chemical Engineering, china University of Petroleum, Dongying 257061, china 2 Department of Chemical Engineering, Hong Kong University of science and technology, Hong Kong, china School of Chemistry & Chemical Engineering China University of Petroleum Dongying China Department of Chemical Engineering Hong Kong University of Science and Technology Hong Kong China

copper (Ⅰ) nitride nanorods grown in channels of mesoporous silica SBA-15 by chemical vapor deposition method has been synthesized. The morphology and microstructure of the resulting product were characterized by XRD patters, TEM images, EDS analysis and Raman spectra. The XRD and TEM revealed that the Cu3N phase was confined in channels of SBA-15 forming continuous nanowires with 6 nm around and hundreds of nanometers in length. Raman spectra of the final product and pure Cu3N showed peaks shift due to the quantum confinement effect of the nanowires. This preparation methodology only requires a mild working condition and is capable of template synthesis of other binary nitride nanostructures with controlled morphology inside the channels of mesoporous materials.

关键词： nanorods copper nitride CVD SBA-15

Matching Performance among Visible and near Infrared coating,Low Infrared Emitting coating and Microwave Absorbing coating

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Journal of Wuhan University of technology(Materials science) 2005年第4期20卷 55-59页

作者：谢国华 college of Materials science and Engineering Beijing University of Astronautics and AeronauticsBeijing 100083ChinaCenter for Surface Materials and TechnologyAerospace Institute of Materials and Processing Technology Beijing 100076China

The matching performance among the visible and near infrared *** low infrared emitting coating and the microwave absorbing coating was *** results show that the resulting malerial is characteristic of wideband effect ranging from the visible,near infrared and 3-5μm,8-14μm infrared protion of the spectrum,as well as the radar region from 8 to 18GHz when these three materials form αlayerstructure material *** microwave absorbing ability of material is hardly *** resonance peak moves towards lower frequency as the thickness of the visible,near infrared coating and the low infrared emitting coating *** problem can be resolved by controlling the thickness of the *** the other hand, the infrared emissivity εof the material system increases as the thickness of the visible,near infrared coating *** can be resolved by increasing infrared transparency of the visible and near infrared topcoating or controlling its *** experimental resulting material system has spectral reflection characteristics in visible and near infrared regions that are similar to those of the natural background.

关键词： visible near infrared infrared microwave camouflage coating