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Journal of Central South university of Technology 2001年第1期8卷 64-68页

作者： PENG Bing 1,PENG Ji 1,ZHANG Chuan fu 1,Jonathan Lobel 2.Janusz A. Kozinski 2.(1 department of Metallurgical science and {2., Central South university, changsha 410083, China 2.department of Metallurgical {2., McGill university department of Metallurgical science and {2. Central South University Changsha China department of Metallurgical engineering McGill University Montreal Canada

The valuable metals in the dust can be recycled by mixing it with reducing agent carbon and lignosulfonate as the binder to make pellets, then returning the pellets to electric arc furnace (EAF) and adding ferro silicon. Part of valuable metals in the dust is reduced by carbon and part of them reduced by ferro silicon for the economical consideration. The reduced metals get into the steel in the stainless steel or special steel production. But the sulfur in the lignosulfonate may affect the quality of produced steel, which is dependent on the status of the smelting slag. The experiments were conducted in the way of changing the ratio of start iron, pellets, ferro silicon and lime. The content of the slag was checked by XRF for the calculation thermodynamics study. The active concentrations of materials in the slag, the slag abilities of oxidation and sulfur removal in EAF dust reduction process were determined by thermodynamics calculation study on CaO MgO FeO Fe 2. 3 SiO 2.S slag at 1 550 ℃. The oxidation ability of slag can be expressed as N (FetO)= N (FeO)+6 N (Fe 2. 3)+8 N (Fe 3O 4). The sulfur removal ability is dependent on the amount of added ferro silicon and the basicity of the slag. The calculation thermodynamics model was set up and it could be applied to the practical production.

关键词： thermodynamics calculation slag electric arc furnace dust

Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics

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science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 257-272页

作者： XU Mingyu1 & TAN Wenchang2.1. Institute of Applied Mathematics, School of Math & System science, Shandong university, Jinan 2.0100, China 2. State Key Laboratory of Turbulence and Complex Systems & {2. of Mechanics and engineering science, Peking university, Beijing 100871, China nl.gov Institute of Applied Mathematics School of Math & System Science Shandong University Jinan 250100 China

From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.

关键词： fractional operators,intermediate processes,critical phenomena,modern mechanics

The optimization of DNA encodings based on GA/SA algorithms

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Progress in Natural science:materials International 2007年第6期17卷 739-744页

作者： Wang Wei1, Zheng Xuedong2. Zhang Qiang1 and Xu Jin2.1. Liaoning Key Laboratory of Intelligent Information Processing, Dalian university, Dalian 11662., China 2. department of Control {2. and engineering, Huazhong university of {2. and Technology, Wuhan 430074, China) Liaoning Key Laboratory of Intelligent Information Processing Dalian University Dalian 116622 China department of Control science and {2. Huazhong University of Science and Technology Wuhan 430074 China

The design of DNA sequence plays an important role in improving the reliability of DNA computation. Proper constrained terms that DNA sequence should satisfy are selected, and then the evaluation formulas of each DNA individual corresponding to the selected constrained terms are proposed. The heuristic improved genetic algorithm (GA)/simulated annealing (SA) algorithm is presented to solve the multi-objective optimize problem, and the DNA sequence design system is developed. Furthermore, an example is illustrated to show the efficiency of our method given here.

关键词： DNA encoding multi-objective optimize GA/SA algorithms

Separation of H_2./CO_2.Mixtures with Layered Adsorption Method for Greenhouse Gas Control

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Chemical Research in Chinese Universities 2012年第1期28卷 129-132页

作者： XU Dong1,2. ZHANG Jun2. LI Gang2. XIAO Penny2.and ZHAI Yu-chun1 1. School of material and Metallurgy, Northeastern university, Shenyang 110004, P. R. China 2. {2. of Chemical engineering, Monash university, Victoria 3800, Australia School of material and Metallurgy Northeastern University Shenyang 110004 department of Chemical engineering Monash University Australia Victoria 3800

Multiple-layered vacuum swing adsorption technique was used and investigated in order to effectively keep the feed gas that flows into zeolite 13X zone being dry and keep the CAPEX down（not adding pre-treatment equipment）. Activated carbon fiber（ACF） and alumina CDX were laid at the lower parts of the column as pre-layers to selectively adsorb moisture. Zeolite 13X was laid on the top of those two adsorbents as the main layer to capture CO2. Systematic cyclic experiments show that water vapor was successfully contained within the ACF and CDX layers at cyclic steady states. It was also found that ultimate vacuum pressure played a decisive factor for stabilizing the water front, and achieving good CO2.purity and recovery. The findings also reveal the pathway for large-scale CO2.capture process.

关键词： Separation Carbon dioxide Water vapor Vacuum swing adsorption

Parameter estimation for whole-body kinetic model of FDG metabolism

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Progress in Natural science:materials International 2006年第11期16卷 1164-1170页

作者： CUI Yunfeng~1, BAI Jing~1**, CHEN Yingmao~2.and TIAN Jiahe~2.1. department of Biomedical engineering, Tsinghua {2., Beijing 100084, China 2. department of Nuclear Medicine, General Hospital of PLA, Beijing 100853, China) department of Biomedical engineering Tsinghua University Beijing 100084 China

Based on the radioactive tracer [ ~ 18 F]2.fluoro-2.deoxy-D-glucose （FDG）, positron emission tomography （PET）, and compartment model, the tracer kinetic study has become an important method to investigate the glucose metabolic kinetics in human body. In this work, the kinetic parameters of three-compartment and four-parameter model for the FDG metabolism in the tissues of myocardium, lung, liver, stomach, spleen, pancreas, and marrow were estimated through some dynamic FDG-PET experiments. Together with published brain and skeletal muscle parameters, a relatively complete whole-body model was presented. In the liver model, the dual blood supply from the hepatic artery and the portal vein to the liver was considered for parameter estimation, and the more accurate results were obtained using the dual-input rather than the single arterial-input. The established whole-body model provides the functional information of FDG metabolism in human body. It can be used to further investigate the glucose metabolism, and also be used for the simulation and visualization of FDG metabolic process in human body.

关键词： compartment model FDG PET parameter estimation.

Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural science:materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2. FENG Zhijing1 and CHENG Kai3(1. State Key Laboratory of Tribiology, Tsinghua university, Beijing 100084, China 2. department of {2. sciences, Changchun university of science and Technology, Changchun 13002., China 3. Faculty of Information and engineering Systems, City Campus, Leeds LS1 3HE, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China department of material {2.s Changchun University of Science and Technology Changchun 130021 China Faculty of Information and engineering Systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.2. nm root mean square (RMS) after 2. min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

A new sequential learning algorithm for RBF neural networks

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science China(Technological sciences) 2004年第4期47卷 447-460页

作者： YANG Ge1, LV Jianhong1 & LIU Zhiyuan2.1. department of Power engineering, Southeast {2., Nanjing 2.0096, China 2. department of Power engineering, Nanjing Institute of Technology, Nanjing 2.0013, China department of Power engineering Southeast University department of Power engineering Nanjing Institute of Technology

Due to their inherent imperfections, it is hard to use the static neural networks for nonlinear time-varying process modeling and prediction, and the minimal resource allocation network (MRAN) is difficult to be realized for its too many regulation parameters. A new sequential learning algorithm for radial basis function (RBF) neural networks based on local projection named Local Projection Network (LPN) is proposed in this paper. The results of validation for several benchmark problems with the new algorithm show that the presented LPN not only has the same level as M-RAN in network size and precision of the outputs, but also has fewer regulation parameters and is more predictable.

关键词： radial basis functions, local projection network, minimal resource allocation network, learning algorithm.

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science China Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. department of Chemistry, Nanjing university of {2. and Technology, Nanjing 2.0094, China 2. Institute of Chemical materials, China Academy of engineering Physics, Mianyang 62.900, China department of Chemistry Nanjing University of Science and Technology Nanjing China Institute of Chemical materials China Academy of Engineering Physics Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural science:materials International 2005年第5期15卷 453-457页

作者： LI Chensha1*, WANG Dazhi1, ZHANG Baoyou2. WANG Xiaofeng1, CAO Maosheng3 and LIANG Ji1(1. department of Mechanical engineering, Tsinghua {2., Beijing 100084, China 2. Center for Analysis and Measurement, Harbin Institute of Technology, Harbin 150001, China 3. School of material science and engineering, Tsinghua {2., Beijing 100084, China) department of Mechanical engineering Tsinghua University Beijing 100084 China Center for Analysis and Measurement Harbin Institute of Technology Harbin 150001 China School of material science and {2. Tsinghua University Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

Electric-stimulus rate encoding algorithm of Mandarin tonal information in cochlear implant

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Progress in Natural science:materials International 2006年第12期16卷 1315-1321页

作者： GUAN Tian~1, GONG Qin~1 and YE Datian~2.*(1. department of Biomedical engineering, Tsinghua {2., Beijing 100084, China 2. Research Center of Biomedical engineering, Graduate School at Shenzhen, Tsinghua {2., Shenzhen 518055, China) department of Biomedical engineering Tsinghua University Beijing 100084 China. Research Center of Biomedical engineering Graduate School Shenzhen Tsinghua University Shenzhen 518055 China

The modern multi-channel cochlear implants usually extract and encode the temporal envelope cues. This kind of algorithms can hardly satisfy the users who speak tonal languages, such as Mandarin. Many studies have tried to enhance the recognition ability of Mandarin through encoding tonal information and made suggestions to frequency-modulate the fixed pulse-rate carrier with the extracted tonal information based on the rate-pitch theory in electric hearing. However, how to encode and deliver the tonal information such as F_0by changing electric-stimulus rate has not got further study in clinical electric-stimulus mode. The present paper focuses on this matter by piecewise calculating the appreciable electric-stimulus rates. Then an electric-stimulus encoding algorithm of Mandarin tone is brought forward and testified through acoustic simulations. Such conclusion can be drawn that this algorithm of electric-stimulus rate could convey tonal information well and help to enhance the Mandarin speech recognition ability.

关键词： cochlear implant tone fundamental frequency electric-stimulus rate.