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PLASMA SPRAYED Ti AND ha COATINGS: A COMPARATIVE STUDY BETWEEN APS AND VPS

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 339-344页

作者： x.B.Zheng H.Ji J.q.Huang C.x.Ding ShanghaiInstituteofCeramics TheChineseAcademyofSciencesShanghai200050China

Titanium (Ti) and hydroxyapatite (ha) coatings have been prepared via air (APS) and vacuum plasma spraying (VPS), and then their composition, structure, bonding strength and bioactivity were examined. The results obtained reveal that in APS process many of Ti were oxidized, but in VPS the oxidization was avoided. VPS T i coating possesses better bonding condition than APS Ti coating. As for ha coat ing, higher crystallinity has been obtained while the coating was deposited by V PS as compared with APS. The simulated body fluid (SBF) tests show that both of APS and VPS ha coatings possess good bioactivity. As compared with APS, VPS is r ecommended as a better method to deposit Ti and ha coatings that can be applied as hard tissue replacement implants.

关键词： vacuum plasma spray Ti ha biocoating

An in-vitro Investigation of Iron-Containing Hydroxyapatite/Titanium Composites

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Journal of Materials Science & Technology 2011年第6期27卷 546-552页

作者： q. Chang H.q. Ru D.L. Chen x.Y. Yue L. Yu C.P. Zhang Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) Northeastern University Shenyang 110004 China Department of Mechanical and Industrial Engineering Ryerson University 350 Victoria Street Toronto Ontario M5B 2K3 Canada

The in-vitro biological behavior of a newly-developed iron-containing hydroxyapatite/titanium（ha/Ti） composite was investigated by immersing the composites in the simulated body fluid（SBF） for up to 5 *** addition of iron was observed to have a significant influence on the in-vitro biological behavior of the *** obtained results revealed that the stability of the composites in the physiological solution was markedly *** solubility decreased in the order of pure ha,ha/5（Ti-33Fe）,and ha/15（Ti33Fe）.Precipitation occurred on the surface of ha/5（Ti-33Fe） composite,showing a good combination of physiostability with bioactivity,while ha/15（Ti-33Fe） composite exhibited superior physiostability since there was no obvious change on the surface of ha/15（Ti-33Fe）.

关键词： Hydroxyapatite composite Iron Titanium Simulated body fluid Biological behavior

THEORETICAL STUDY OF GIANT MAGNETO-IMPEDANCE IN AMORPHOUS FILMS WITH LONGITUDINAL MAGNETIC ANISOTROPY

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Acta Metallurgica Sinica(English Letters) 2000年第4期13卷 995-1000页

作者： Yu, J.q. Zhou, Y. Cai, B.C. Zhao, x.L. Shanghai Jiaotong Univ Shanghai China

Giant magneto-impedance (MI) effect in thin films with longitudinal magnetic anisotropy was studied theoretically. The effective permeability of films as a function of external magnetic field ha, anisotropy field and other parameters of films was presented by Landau-Lifshitz-Gilbert theory. The theoretical results agree well with the experimental data, which shows a strong dependence of the impedance on the applied magnetic field.

关键词： Electric currents Magnetic anisotropy Magnetic fields Skin effect

Support vector machine based machine learning method for GS 8qAM constellation classification in seamless integrated fiber and visible light communication system

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Science China(Information Sciences) 2020年第10期63卷 182-193页

作者： Wenqing NIU Yinaer ha Nan CHI Key Laboratory for Information Science of Electromagnetic Waves (MoE) Fudan University

Visible light communication(VLC) network over optical fiber has become a potential candidate in ultra-high speed indoor wireless communication. To mitigate signal distortion accumulated in optical fiber and VLC channel, we present to utilize support vector machine(SVM) for constellation classification in two kinds of geometrically-shaped 8 qAM(quadrature amplitude modulation) seamless integrated fiber and VLC system. We introduce 4 sub-bands to simulate multi-user. Experimental results show that system performance can be significantly improved, and transmission at-2.5 dB m input optical power under 7%forward error correction(FEC) threshold can be realized employing Circular(7, 1) geometrically-shaped8 qAM and SVM. At overall capacity of 960 Mbps, q-factor increases by up to 11.5 dB.

关键词： visible light communication VLC support vector machine SVM geometrically shaping GS VLC network constellation classification

Sol-gel derived ha/TiO_2 double coatings on Ti scaffolds for orthopaedic applications

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中国有色金属学会会刊：英文版 2006年第B01期16卷 209-216页

作者： xU W HU W Y LI M H MA q q P. D. HODGSON WEN C E Department of Applied Physics Hunan University Changsha 410082 China Centre for Material and Fibre Innovation Deakin University Geelong Vic 3217 Australia

Hydroxyapatite/titania (ha/TiO2) double layers were coated onto Ti scaffolds throughout for orthopaedic applications by sol-gel method. Differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and x-ray diffractometry (xRD) were used for the characterisation of the phase transformations of the dried gels and coated surface structures. Scanning electron microscope (SEM) equipped with energy dispersive spectrometry (EDS) was used for the observation and evaluation of the morphology and phases of the surface layers and for the assessment of the in vitro tests. The in vitro assessments were performed by soaking the ha/TiO2 double coated samples into the simulated body fluid (SBF) for various periods. The TiO2 dipping-coating method at a speed of 12 cm/min, followed by a heat treatment at 600 ℃ for 20 min. The ha la lyaeyre wr wasa ssu cbosaetqeude bnytl ya dipping-coated on the outer surface at the same speed and then heat-treated at difference temperatures. The results indicat that the ha phase begins to crystallize after a heat treatment at 560 ℃. The crystallinity increases obviously at 760 ℃. SEM observations find no delamination or crack at the interfaces of ha/TiO2 and TiO2/Ti. The ha/TiO2 coated Ti scaffolds displays excellent bone-like apatite forming ability when it is soaked into SBF. Ti scaffolds after ha/TiO2 double coatings can be anticipated as promising implant materials for orthopaedic

关键词：钛支架溶胶-凝胶法羟基磷灰石/二氧化钛涂层医学整形外科应用

基于Dueling DqN算法的列车运行图节能优化研究

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都市快轨交通 2024年第2期37卷 39-46页

作者：刘飞唐方慧刘琳婷胡文斌哈进兵钱程苏州市轨道交通集团有限公司运营管理中心江苏苏州215101 南京理工大学南京210014

通过优化地铁时刻表可有效降低地铁牵引能耗。为解决客流波动和车辆延误对实际节能率影响的问题,提出列车牵引和供电系统实时潮流计算分析模型和基于Dueling Deep q Network(Dueling DqN)深度强化学习算法相结合的运行图节能优化方法,... 详细信息

通过优化地铁时刻表可有效降低地铁牵引能耗。为解决客流波动和车辆延误对实际节能率影响的问题,提出列车牵引和供电系统实时潮流计算分析模型和基于Dueling Deep q Network(Dueling DqN)深度强化学习算法相结合的运行图节能优化方法,建立基于区间动态客流概率统计的时刻表迭代优化模型,降低动态客流变化对节能率的影响。对预测q网络和目标q网络分别选取自适应时刻估计和均方根反向传播方法,提高模型收敛快速性,同时以时刻表优化前、后总运行时间不变、乘客换乘时间和等待时间最小为优化目标,实现节能时刻表无感切换。以苏州轨道交通4号线为例验证方法的有效性,节能对比试验结果表明:在到达换乘站时刻偏差不超过2 s和列车全周转运行时间不变的前提下,列车牵引节能率达5.27%,车公里能耗下降4.99%。

关键词：城市轨道交通时刻表优化牵引节能 Dueling DqN 动态客流

Applicability of large-ion lithophile and high field strength element basalt discrimination diagrams

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International Journal of Digital Earth 2018年第7期11卷 752-760页

作者： x.L.Liu q.Zhang W.C.Li F.C.Yang Y.Zhao Z.Li S.T.Jiao J.R.Wang N.Zhang S.S.Wang W.F.Chen Z.J.Pan J.Yang x.L.Du Faculty of Land and Resource Engineering Kunming University of Science and TechnologyKunmingPeople’s Republic of China Institute of Geology and Geophysics Chinese Academy of SciencesBeijingPeople’s Republic of China Chengdu Geological Survey Center of China Geological Survey ChengduPeople’s Republic of China School of Earth Science Lanzhou UniversityLanzhouPeople’s Republic of China

Basalt discriminant diagrams have been used to identify the tectonic setting of basaltic magmatism since the 1970s and have played an important role in reconstructing paleotectonic ***,the significant increase in the availability of geochemical data has led to a reassessment of these diagrams,suggesting that some of the tectonic settings indicated by these diagrams are not ***,we use a database of global ocean island basalt(OIB),mid-ocean ridge basalt(MORB),and island arc basalt(IAB)geochemistry to propose a series of new tectonic discriminant diagrams based on the ratios of large-ion lithophile elements(LILEs)to high field strength elements(HFSEs).These new diagrams indicate that the LILE can be used to differentiate OIB,MORB,and IAB samples,meaning that LILE/HFSE ratios can discriminate between these basalts that form in different tectonic *** new diagrams can correctly assign samples to OIB,MORB,and IAB categories more than 85%of the time,with the discrimination between OIB and MORB having an accuracy of slightly less than 85%.

关键词： Basalt LILE HFSE discrimination diagram geochemistry

Root growth dynamics during recovery of tropical mountain forest in North-east India

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Journal of Mountain Science 2019年第10期16卷 2335-2347页

作者： Chalthleng LALNUNZIRA Francis q.BREARLEY Shri Kant TRIPATHI Department of Forestry Mizoram UniversityAizawl 796 004India School of Science and the Environment Manchester Metropolitan UniversityChester StreetManchesterM1 5GDUK

Ever increasing pressures on tropical forests worldwide due to anthropogenic disturbances have greatly affected both above-and belowground functioning of these *** fine roots play major ecological roles in forests through assisting in nutrient and water uptake and returning elements to the soil environment,coarse roots play an important role in C *** studied changes in fine and coarse root biomass,production,turnover and carbon and nitrogen return to the soil in two regenerating forest stands(RFs)following stonemining that were 5 years(RF-5)and 15 years(RF-15)post-disturbance compared with a natural forest stand(NF)in Mizoram,North-east ***(han for rainfall and temperature,whereas these relationships were less clear for the coarse root *** amount of N(25-55 kg ha-1)and C(1.9-3.6t ha-1)stored in root biomass increased with stand age with a corresponding increase in production and turnover of C and N to the *** to these tropical forests negatively affected root dynamics,influenced their spatiotemporal patterns,and reduced the production,amount and availability of nutrients returned to the soil along with a strong reduction in the root biomass carbon pool and sequestration in carbon residence *** observed that root growth,especially fine roots,is dependent on abiotic variables,and plays a significant role in early stages of secondary succession by adding organic matter and nutrients through high turnover rates in these forests.

关键词： Total root biomass Element return Regenerating forest Root production and turnover Anthropogenic disturbance

Vibration characteristics of piezoelectric functionally graded carbon nanotube-reinforced composite doubly-curved shells

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Applied Mathematics and Mechanics(English Edition) 2021年第6期42卷 819-840页

作者： V.V.ThaM H.q.TRANT T.M.TU National Univensity of Ciwil Engineering Giai Phong Road 55Hai Ba Trung DistrictHanoi 100000 Vietnam

This paper presents an analytical solution for the free vibration behavior of functionally graded carbon nanotube-reinforced composite(FG-CNTRC) doubly curved shallow shells with integrated piezoelectric layers. Here, the linear distribution of electric potential across the thickness of the piezoelectric layer and five different types of carbon nanotube(CNT) distributions through the thickness direction are considered. Based on the four-variable shear deformation refined shell theory, governing equations are obtained by applying hamilton's principle. Navier's solution for the shell panels with the simply supported boundary condition at all four edges is derived. Several numerical examples validate the accuracy of the presented solution. New parametric studies regarding the effects of different material properties, shell geometric parameters, and electrical boundary conditions on the free vibration responses of the hybrid panels are investigated and discussed in detail.

关键词： free vibration four-variable shear deformation refined theory functionally graded carbon nanotube-reinforced composite(FG-CNTRC) piezoelectric material