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Prediction of Gas Emission Based on Infor-mation Fusion and Chaotic Time Series

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Journal of China University of Mining and Technology 2006年第1期16卷 94-96页

作者： GAO li yu hong-zhen College of Information and ElectricaI Engineering China University of Mining ＆ Technolog Xuzhou Jiangsu 221008 China

In order to make more exact predictions of gas emissions, information fusion and chaos time series are com- bined to predict the amount of gas emission in pits. First, a multi-sensor information fusion frame is established. The frame includes a data level, a character level and a decision level. Functions at every level are interpreted in detail in this paper. Then, the process of information fusion for gas emission is introduced. On the basis of those data processed at the data and character levels, the chaos time series and neural network are combined to predict the amount of gas emission at the decision level. The weights of the neural network are gained by training not by manual setting, in order to avoid subjectivity introduced by human intervention. Finally, the experimental results were analyzed in Matlab 6.0 and prove that the method is more accurate in the prediction of the amount of gas emission than the traditional method.

关键词： gas emission information fusion chaos time series neural network

Temperature Effect on the Mechanical Behavior of Acrylic Polymers under Quasi-static and Dynamic Loading

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上海交通大学学报 2004年第z2期38卷 89-95页

作者： Tao Suo yulong li hong yu Fei Xu Zhongbin Tang Lei li School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China School of Aeronautics Northwestern Polytechnical University Xi''an710072 China Beijing Institute of Aeronautical Materials Beijing100095China

In this paper, the mechanical behavior of acrylic polymers at elevated temperature was investigated. Four acrylic polymers were tested at high strain rate by using compression Hopkinson bar and at quasi-static strain rate by using an Instron servo hydraulic axial testing machine with the testing temperature from 218K to 393K. The results show that the mechanical property of acrylic polymers depends heavily on the testing temperature. The yield stress and Young's modulus were found to decrease with increasing temperature at low strain rate. At very low temperature, the materials display typical brittle fracture; however their plasticity improves remarkably at high temperatures. The predictions of the mechanical behavior including the effect of temperature and strain rate using a proposed theoretical model have a good agreement with experimental results.

关键词： acrylic polymer compression Hopkinson bar quasi-static dynamic fracture

Comparison of 1.5% lidocaine and 0.5% ropivacaine epidural anesthesia combined with propofol general anesthesia guided by bispectral index

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第6期8卷 428-434页

作者： XIANG Yan li yu-hong Department of Anesthesiology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： To compare the effects of epidural anesthesia with 1.5% lidocaine and 0.5% ropivacaine on propofol requirements, the time to loss of consciousness （LOC）, effect-site propofol concentrations, and the hemodynamic variables during induction of general anesthesia guided by bispectral index （BIS） were studied. Methods： Forty-five patients were divided into three groups to receive epidurally administered saline （Group S）, 1.5% （w/w） lidocaine （Group L）, or 0,5% （w/w） ropivacaine （Group R） Propofol infusion was started to produce blood concentration of 4 lag/ml. Once the BIS value reached 40-50, endotracheal intubation was facilitated by 0.1 mg/kg vecuronium. Measurements included the time to LOC, effect-site propofol concentrations, total propofol dose, mean arterial blood pressure （MABP）, and heart rate （HR） at different study time points. Results： During induction of anesthesia, both Groups L and R were similar for the time to LOC, effect-site propofol concentrations, total propofol dose, MABP, HR, and BIS. The total doses of propofol administered until 1 min post-intubation were significantly less in patients of Groups R and L compared with Group S. MABP and HR were significantly lower following propofol induction compared with baseline values in the three groups, or MABP was significantly increased following intubation as compared with that prior to intubation in Group S but not in Groups R and L while HR was significantly increased following intubation in the three groups. Conclusion： Epidural anesthesia with 1.5% lidocaine and 0.5% ropivacaine has similar effects on the time to LOC, effect-site propofol concentrations, total propofol dose, and the hemodynamic variables during induction of general anesthesia.

关键词： Propofol lidocaine Ropivacaine Epidural anethesia Bispectral index

Performance analysis of a rate adaptive multi-band ultra-wideband system based on quadrature fractal modulation scheme

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通信学报 2005年第10期26卷 34-40页

作者： li yu-hong ZHOU Zheng Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 China

A rate adaptive multi-band ultra-wideband (UWB) system based on the quadrature fractal modulation (QFM) scheme was *** the use of homogeneous signals as modulating waveforms in UWB system,the signal within each 528MHz sub-band was divided into 8 different frequency bandwidths using wavelets transform and these data sequences to be transmitted were embedded into homogeneous *** is found that the use of homogeneous signals in such UWB system is quite feasible,leadings to a novel multi-rate diversity *** each 528MHz sub-band,the UWB-QFM system can provide much higher data rates than that of the UWB orthogonal frequency division multiplexing (OFDM) *** results also show that the bit error rate (BER) performance of the UWB-QFM system achieves a greatly improvement over existing UWB-OFDM *** to the fractal properties of the homogeneous signals,these data sequences to be transmitted can be recovered using arbitrarily short receiver signal.

关键词：多频率传输积分调制微波传输直角频率分割多路技术

Coarsening and Age Hardening Behaviors of γ' Particles in GH742 During High Temperature Treatment

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Journal of Iron and Steel Research International 2009年第5期16卷 81-86页

作者： li hong-yu SONG Xi-ping WANG Yan-li CHEN Guo-liang State Key Lab for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The coarsening and ageing hardening behaviors of γ′ particles in superalloy GH742 have been investigated by field emission scanning electron microscopy （FESEM）, coarsening kinetics calculation and microhardness testing when ageing at 1 050, 950 and 900 ℃ for different time. The cube of γ′ particle size and ageing time follows a linear law as predicted by LSW theory. The particle size distributions give better fit to the LSW theoretical distribution. The activation energy for γ′ coarsening is accurately determined to have 245. 06±14.42 kJ/mol when considering the effect of temperature on the solution concentrations in matrix. Based on the activation energy, the coarsening kinetics of γ′ particle is predicted as r^-t^3=7.35×10^15 Ce/T exp -（245060±14420）/RT *** microhardness studies indicate that microhardness decreases rapidly with increasing the ageing temperature and it has a maximum value corresponding to a critical particle size beyond which the microhardness increase stalls with increasing the ageing time.

关键词： superalloy γ′ particle coarsening kinetics activation energy microhardness

Preparation,Structure and Mechanical Properties of Nickel Based Porous Spherical Superalloy

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Journal of Iron and Steel Research International 2009年第1期16卷 92-96页

作者： MI Guo fa li hong-yu liU Xiang-yu WANG Kuang-fei School of Materials Science and Engineering Henan Polytechnic University Jiaozuo 454000 Henan China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 Heilongjiang China

The porous superalloy materials with hollow spherical pores were fabricated by using metal powder sintering process. The scanning electron microscope （SEM） observation was applied to the test samples and it revealed that the pores of the porous material exhibited a uniform distribution and the apertures were of same size in principle. The sintering necks appeared between adjacent particles on metal skeleton after sintering. The mechanical properties of the test samples were analyzed and the result showed that this kind of materials possessed excellent energy absorption capability, and the compression resistance decreased with increasing the porosity and aperture.

关键词： porous superalloy material metal powder sintering hollow spherical pore oriented linear pore

Partitioning of heavy metals in the surface sediments of Quanzhou Bay wetland and its availability to Suaeda australis

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Journal of Environmental Sciences 2006年第2期18卷 334-340页

作者： li yu-hong YAN Chong-ling yuAN Jian-jun liU Jing-chun CHEN Huai-yu HU Jun School of life Sciences Xiamen University Xiamen 361005 China State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China iology Department of Quanzhou Normal College Quanzhou 362000 China

In order to investigate distributions of heavy metal pollution in Quanzhou Bay wetland, the total concentration and chemical partitioning of a number of heavy metals （Cu, Zn, Cd, Pb, Cr, Hg） in sediments of three sampling sites of Quanzhou Bay wetland and their availability to Suaeda australis were analyzed. The Geoaccumulation Index （Igeo） values reveal that the sediments of three sampling sites may all be considered as moderately contaminated for Pb and Zn, and all sediments might be strongly contaminated with cadmium. The partitioning analyses revealed the measured heavy metals in three sites are bound to the exchangeable fraction at lower concentrations. The measured metals in a considerable amount are bound to the reducible and oxidizable fractions, and a high proportion of the measured heavy metals were distributed in the residual fraction in the sediment samples. The concentrations of Cd in each chemical phase extracted from the sediments are above natural global background levels and should be further investigated because of its toxicity. Suaeda australis has different accumulation abilities for the measured heavy metals. For the root and stem, the bioaccumulation ability assessed by bioaccumulation factor （BAF） for the measured heavy metals follows the decreasing order as： Cu〉Cr〉 Zn〉Cd, Pb, Hg. In the leaf, stronger bioaccumulation ability for Hg is exhibited. The heavy metal concentrations in Suaeda australis roots have positive correlations with their available fractions, while the exchangeable fraction of Cu and Cd might have be more important to both mature plant roots and seedling roots uptake than other fractions; as for Cr, the oxidizable fraction might make a greater contribution to the plant root uptake; as for Zn, the reducible fraction might make so contribution ; and for Pb, the oxidizable fraction might make a significant contribution to the mature plant root uptake, however, the exchangeable fraction might have a significant contribution to th

关键词： bioavailability geoaccumulation factor partitioning heavy metals Suaeda australis sediment Quanzhou Bay wetland

Fabrication and Photoelectrochemical Properties of[Ru(bpy)_2dppz]^(2+) on ITO Electrode Associated with the Oxidation of Guanine

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Chemical Research in Chinese Universities 2010年第4期26卷 649-655页

作者： GUO Qing-yu li hong YANG Hui-yi SHAO Jiang-yang Key Lab of Technology on Electrochemical Energy Storage and Power Generation in Guangdong Universities School of Chemistry and Environment South China Normal University Guangzhou 510006 P. R. China

Electrochemical assembly of [Ru（bpy）2dppz]^2＋{bpy=2,2＇-bipyridine, dppz=dipyrido[3,2-a：＂2＇,3＇-c]phenazine} on an ITO electrode in the presence of guanine and photoelectroehemical properties of the assembled layer were investigated. It has been found that [Ru（bpy）2dppz]^3＋/2＋ can be assembled onto the ITO electrode by the method of repetitive voltammetric sweeping, and the assembly is enhanced by guanine. The peak currents of prewaves increase linearly up to a guanine concentration of 0.25 mmol/L. More importantly, upon illumination with 470 nm light source and at an applied potential of 0.2 V, cathodic current for the fabricated layer on the ITO electrode indicate a linear enhancement with the rise of guanine concentration. Meanwhile, [Ru（bpy）2dppz]^2＋ can be served as an excellent mediator to prompt the oxidation of guanine, and the mediated peak current increases linearly with added guanine concentration from 0.01 to 0.25 mmol/L. In addition, the assembly mechanism of [Ru（bpy）2dppz]^2＋ on the ITO electrode associated with the oxidation of guanine and the assistance of light irradiation were discussed.

关键词： Polypyridvl ruthenium(II) complex Guanine ITO Assembly Photoelectrochemistrv

Online upgrading of organic vapors from the fast pyrolysis of biomass

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燃料化学学报 2008年第6期36卷 666-671页

作者： li hong-yu YAN Yong-jie REN Zheng-wei Research Center for Biomass Energy State Key Laboratory of Bioreactor Engineering East China University of Scince and Technology Shanghai 200237

The online upgrading process that combined the fast pyrolysis of biomass and catalytic cracking of bio-oil was developed to produce a high quality liquid product from the *** installation consisted of a fluidized bed reactor for pyrolysis and a packed bed reactor for *** proper pyrolysis processing conditions with a temperature of 500℃ and a flow rate of 4m3·h-1 were determined in *** such conditions,the effects of temperature and weight hourly space velocity(WHSV) on both the liquid yields and the oil qualities of the online catalytic cracking process were *** results showed that such a combined process had the superiority of increasing the liquid yield and improving the product quality over the separate ***,when the temperature was 500℃,with a WHSV of 3h-1,the liquid yield reached the maximum and the oxygenic compounds also decreased obviously.

关键词：有机水蒸气高温分解反应生物量化学分析