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中国有色金属学会会刊：英文版 2004年第z1期14卷 315-318页

作者： MA Shi-ning HU chun-hua li Xin QIU Ji Department of Materials Science and Engineering Academy of Armored Force Engineering Beijing 100072 China Department of Materials Science and EngineeringAcademy of Armored Force Engineering Beijing 100072 China Department of Materials Science and EngineeringAcademy of Armored Force Engineering Beijing 100072 China Department of Materials Science and EngineeringAcademy of Armored Force Engineering Beijing 100072 China

Composite layer with nitrocarbonide and sulfide was made on the surface of CrMoCu alloy cast iron by combined treatment of ion nitrocarburizing and sulphurizing. The composite layer is composed of sulfide layer, nitrocarbonide hypo-surface layer and its diffusing layer, the size of sulfide globular grains distributing equably on the surface is in nano-micron-scale, and the phase structure of the composite layer is composed of FeS, FeS1-x, Fe2C and Fe3N. Under oil lubrication, sulphurized surface shows good scuffing-resistance only under low velocity, and nitrocarburized and sulphurized surface greatly improves the scuffing-resistance and wear-resistance of CrMoCu alloy cast iron, its integrated friction and wear properties are better than those of the plain and sulphurized surfaces under all the velocities.

关键词： ion nitrocarburizing ion sulphurizing combined treatment friction and wear properties

Microstructural evolution in electroformed nickel shaped-charge liners with nano-sized grains undergone deformation at ultrahigh strain rate

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 617-623页

作者： Feng Yang chun-hua li Sheng-wei Cheng Lei Wang Wen-huai Tian School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Nickel shaped-charge liners with nano-sized grains were prepared by the electroforming technique, and the deformation at ultrahigh strain rate was performed by explosive detonation. The as-formed and post-deformed microstructures of electroformed nickel shaped-charge liners with nano-sized grains were observed by means of transmission electron microscopy, and the orientation distribution of the grains was analyzed by the electron backscattering pattern （EBSP） technique. The melting phenomenon in the jet fragment and the recovery and recrystallization in the slug after plastic deformation at ultrahigh-strain rate were observed in the ultrafine-grained nickel shaped-charge liners. The research evidence shows that dynamic recovery and recrystallization play an important role in plastic deformation at ultrahigh strain rate.

关键词： electroformed nickel nanosized plastic deformation electroformation microtexture dynamic recovery and recrystallization

Anaerobic biodegradation of PAHs in mangrove sediment with amendment of NaHCO_3

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Journal of Environmental Sciences 2015年第4期27卷 148-156页

作者： chun-hua li Yuk-Shan Wong Hong-Yuan Wang Nora Fung-Yee Tam State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Department of Biology and Chemistry City University of Hong Kong Department of Biology The Hong Kong University of Science and Technology Key Laboratory of Nonpoint Source Pollution Control Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences State Key Laboratory on Marine Pollution City University of Hong Kong

Mangrove sediment is unique in chemical and biological properties. Many of them suffer polycyclic aromatic hydrocarbon（PAH） contamination. However, the study on PAH biological remediation for mangrove sediment is deficient. Enriched PAH-degrading microbial consortium and electron acceptor amendment are considered as two effective measures. Compared to other electron acceptors, the study on CO2, which is used by methanogens, is still seldom. This study investigated the effect of Na HCO3 amendment on the anaerobic biodegradation of four mixed PAHs, namely fluorene（Fl）, phenanthrene（Phe）,fluoranthene（Flua） and pyrene（Pyr）, with or without enriched PAH-degrading microbial consortium in mangrove sediment slurry. The trends of various parameters, including PAH concentrations, microbial population size, electron-transport system activities, electron acceptor and anaerobic gas production were monitored. The results revealed that the inoculation of enriched PAH-degrading consortium had a significant effect with half lives shortened by 7–13 days for 3-ring PAHs and 11–24 days for 4-ring PAHs. While Na HCO3 amendment did not have a significant effect on the biodegradation of PAHs and other parameters, except that CO2 gas in the headspace of experimental flasks was *** of the possible reasons is that mangrove sediment contains high concentrations of other electron acceptors which are easier to be utilized by anaerobic bacteria, the other one is that the anaerobes in mangrove sediment can produce enough CO2 gas even without adding Na HCO3.

关键词： Anaerobic biodegradation Electron acceptor amendment Mangrove sediment Na HCO3amendment Polycyclic aromatic hydrocarbon

Improved PSO algorithm and its application

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Journal of Central South University of Technology 2005年第z1期12卷 222-226页

作者： li Yong-gang GUI Wei-hua YANG chun-hua li Jie School of Information Science and Engineering Central South University Changsha 410083 China School of Metallurgical Science and Engineering Central South University Changsha 410083 China School of Information Science and Engineering Central South University Changsha 410083 China School of Information Science and Engineering Central South University Changsha 410083 China School of Metallurgical Science and Engineering Central South University Changsha 410083 China

The mechanism of particle swarm optimization algorithm is studied, and one can draw the conclusion that the best particle found by the swarm falling into local minima is one of the main reasons for premature convergence. Therefore, an improved particle swarm optimization algorithm is proposed. This algorithm selects the best particle with roulette wheel selection method, so premature converging to local optima is avoided. At last, the improved particle swarm optimization algorithm is applied to optimization of time-sharing power supply for zinc electrolytic process. Simulation and practical results show that the global search ability of IPSO is improved greatly and optimization of time-sharing power supply for zinc electrolytic process can bring about outstanding economic benefit for plant.

关键词： particle swarm optimization premature convergence roulette wheel zinc electrolytic process timesharing power supply

A maximum power point tracker for photovoltaic energy systems based on fuzzy neural networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 263-270页

作者： chun-hua li Xin-jian ZHU Guang-yi CAO Wan-qi HU Sheng SUI Ming-ruo HU Fuel Cell Research Institute Shanghai Jiao Tong University Shanghai 200240. China Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

To extract the maximum power from a photovoltaic （PV） energy system, the real-time maximum power point （MPP） of the PV array must be tracked closely. The non-linear and time-variant characteristics of the PV array and the non-linear and non-minimum phase characteristics of a boost converter make it difficult to track the MPP for traditional control strategies. We propose a fuzzy neural network controller （FNNC）, which combines the reasoning capability of fuzzy logical systems and the learning capability of neural networks, to track the MPP. With a derived learning algorithm, the parameters of the FNNC are updated adaptively. A gradient estimator based on a radial basis function neural network is developed to provide the reference information to the FNNC. Simulation results show that the proposed control algorithm provides much better tracking performance compared with the filzzy logic control algorithm.

关键词： Photovoltaic array Maximum power point tracking (MPPT) Fuzzy neural network controller (FNNC) Radial basis function neural network (RBFNN)

Confirmed Diagnosis by RT-PCR and Phylogenetic Analysis of Peste des Petits Ruminants Viruses in Tibet, China

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Virologica Sinica 2009年第6期24卷 573-578页

作者： Wen-hua ZHAO Shi-biao YANG Jian-qiang HAN Mei JIANG hua-chun li Nian-zu ZHANG Qi-han li Laboratory of Tropical and Subtropical Animal Virology of MOA National Exotic Animal Disease Diagnostic Laboratory Kunming 650224 China Yu Xi Agriculture Vocational Technical College Yu Xi 653100 China Peking Union Medical College Tsinghua University Kunming Jiaoling Road 3 79# Kunming 65011 8 China

This paper reports the confirmed diagnosis by nested RT-PCR of PPR cases in Tibet, China in 2007, and results of phylogenetic analysis. Results showed that the 11 tested samples were PPRV positive by nested RT-PCR, of which 2 samples were genetically close to the X7443 strain (Nigeria 75/1) of lineage I, and 3 samples close to the strain AY560591 (Sungri96) of linage IV with 96.6%、97.3%、97.6% and 98% nucleotide sequence homogeneity respectively, based on partial sequencing of the F gene from 5 samples and complete sequencing of the N/M/F/H genes from one sample. This study suggested that there are at least 2 origins of PPRV in China.

关键词： Peste des petitis ruminants virus (PPRV) Tibet RT-PCR Open reading frame (ORF) Phylogenetic analysis

Study on Friction and Wear Characteristics and Structure of Compound Layer from Combined Treatment of Ion Nitrocarburizing-Ion Sulphurizing of CrMoCu Alloy Cast Iron

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材料热处理学报 2004年第05B期25卷 649-652页

作者： MAShi-ning HUchun-hua liXin QIUJi AcademyofArmoredFotceEngineering BeijingChina

The technics of combined treatment of ion nitrocarburizing-ion sulphurizing of CrMoCu alloy cast iron has been investigated and the compound layer with nitrocarbonide and sulphide has been made on the surface of CrMoCu alloy cast iron. The compound layer is composed of sulfide surface layer and the nitrocarbonide hypo-surface layer and its diffusing layer. The size of sulfide globular grains distributing equably on the surface is in nano-rnicron-scale, and the phase structure of the compound layer is composed of FeS^ FeSi^ Fe2C and Fe3N. Under dry sliding condition, the friction-reducing of sulphurized surface is good, but its function time can’t last very long. The nitrocarbonided+sulphurized surface can greatly improve the wear-resistance and the friction-reducing of CrMoCu alloy cast iron, and its integrated friction and wear properties are better than plain and sulphurized surfaces’.

关键词：离子碳氮共渗 CrMoCu合金离子渗硫联合处理磨损性能

Research on magnetic centermeasurement of quadrupole and sextupole using vibrating wire alignment technique in HEPS-TF

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Radiation Detection Technology and Methods 2018年第2期2卷 140-147页

作者： Lei Wu Xiao-long Wang chun-hua li hua-min Qu Zi-hao Wang Min-xian li ling-ling Gong Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Institute of Neutron Sciences Dongguan 523808China University of Chinese Academy of Sciences Beijing 100049China

Purpose In order to meet the extremely low emittance requirement,the magnets in the storage ring of high-energy photon source(HEPS)need to have a stable support and precise *** HEPS-TF,the key and difficult technologies of HEPS should be researched and *** wire alignment technique is one important project of *** can be used to pre-align the quadrupoles and sextupoles on one girder with high precision.A vibrating wire measurement system was set up and tested to verify the magnetic center measurement precision and the magnet adjustment *** There are one sextupole and one quadrupole installed on a multipole *** wire is stretched through mechanical center of the magnet apertures and supported by the test benches on the two sides.A single conducting wire is stretched through themagnet aperture and electrified by alternating *** wire will vibrate for a period of Lorentz *** matching the current frequency to one mode of natural frequency of the wire,the vibrating amplitude will be *** by measuring the vibrating amplitude,the magnetic field at the wire position can be *** the wire across the magnet aperture in the transversal or vertical direction,the distribution of magnetic field and magnetic center position can be *** to the magnetic center position error to adjust the *** the magnetic center of all magnets installed on the multipole girder one by one,and adjust their magnetic center to a *** The magnetic center measurement precision is better than±3μm,and the magnet adjustment error is less than 6μ*** The vibrating wire system design and a series of magnetic center measurement experiments have gained good *** has been proved the vibrating wire system is designed reasonable and using the vibrating wire to align the magnets installed on a multipole girder is feasible and can reach a high precision.

关键词： Vibrating wire Magnetic center Measurement precision Magnet adjustment

Redistribution of Pb, Zn and Cu Fractions in Tailing Soils Treated with Different Extractants

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Pedosphere 2006年第3期16卷 312-318页

作者： liU Yun-Guo WANG Xian-Hai ZENG Guang-Ming li Xin ZHOU chun-hua FAN Ting li Yong-li YUAN Xin-Zhong Department of Environmental Science and Engineering Hunan University Changsha 410082 （China） Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China） Graduate School of Chinese Academy of Sciences Beijing 100039 （China）

The efficiency of EDTA, HNO3 and CaCl2 as extractants to remove Pb, Zn and Cu from tailing soils without varying soil pH was investigated with distributions of Pb, Zn and Cu being determined before and after extraction using the sequential extraction procedure of the optimized European Community Bureau of Reference (BCR). Results indicated that EDTA and HNO3 were both effective extracting *** extractability of extractants for Pb and Zn was in the order EDTA > HNO3 > CaCl2, while for Cu it was HNO3 > EDTA > CaCl2. After EDTA extraction, the proportion of Pb, Zn and Cu in the four fractions varied greatly, which was related to the strong extraction and complexation ability. Before and after extraction with HNO3 and CaCl2, the percentages of Pb, Zn and Cu in the reducible, oxidizable and residual fractions changed little compared to the acid-extractable fraction. The lability of metal in the soil and the kinds of extractants were the factors controlling the effects of metal extraction.

关键词： BCR extraction fraction heavy metals redistribution

Quantitative analysis by reversed-phase high-performance liquid chromatography and retinal neuroprotection after topical administration of moxonidine

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International Journal of Ophthalmology(English edition) 2020年第3期13卷 390-398页

作者： Qian Zhang Mei-Fang Chu Yan-Hong li chun-hua li Run-Jia Lei Si-Cen Wang Bao-Jun Xiao Jian-Gang Yang Department of Ophthalmology Xi’an Fourth HospitalShaanxi Ophthalmological HospitalXi’an 710004Shaanxi ProvinceChina Xi’an Eye Hospital First Affiliated Hospital of Northwest UniversityXi’an No.1 HospitalXi’an 710002Shaanxi ProvinceChina School of Pharmacy Xi’an Jiaotong UniversityXi’an 710068Shaanxi ProvinceChina West Street Community Health Center of lianhu District Xi’an 710002Shaanxi ProvinceChina

AIM:To determine moxonidine in aqueous humor and iris-ciliary body by reversed-phase high performance liquid chromatography(RP-HPLC),and to evaluate the retinal neuroprotective effect after topical administration with moxonidine in a high intraocular pressure(IOP)***:The eyes of albino rabbits were administered topically and ipsilaterally with 0.2%moxonidine.A RPHPLC method was employed for the identification and quantification of moxonidine between 2 and 480 min,which presented in the aqueous humor and iris-ciliary *** electroretinography(F-ERG)amplitude and superoxide dismutase(SOD)level were measured between day 1 and day 15 after topical administration with moxonidine in a rabbit model of high *** and ultrastructural observation underwent to analyze the changes of retinal morphology,the inner retinal layers(IRL)thickness,and retinal ganglion cell(RGC)***:Moxonidine was detectable between 2 and 480 min after administration,and the peak concentration developed both in the two tissues at 30 min,0.51μg/m lin aqueous humor and 1.03μg/g in iris-ciliary *** comparison to control,F-ERG b-wave amplitude in moxonidine eyes were significantly differences between day 3 and day 15(Plication to high IOP *** layers of retina,including RGC layer,retinal nerve fiber layer and INL,are more preserved after moxonidine *** plays a neuroprotective role in ocular hypertension-mediated RGC death.

关键词： reversed-phase high-performance liquid chromatography moxonidine retinal ganglion cell neuroprotection superoxide dismutase